Resguardo inicial

linux-7.2.3/drivers/net/wireguard/Makefile

@@ -0,0 +1,17 @@
+ccflags-y := -D'pr_fmt(fmt)=KBUILD_MODNAME ": " fmt'
+ccflags-$(CONFIG_WIREGUARD_DEBUG) += -DDEBUG
+wireguard-y := main.o
+wireguard-y += noise.o
+wireguard-y += device.o
+wireguard-y += peer.o
+wireguard-y += timers.o
+wireguard-y += queueing.o
+wireguard-y += send.o
+wireguard-y += receive.o
+wireguard-y += socket.o
+wireguard-y += peerlookup.o
+wireguard-y += allowedips.o
+wireguard-y += ratelimiter.o
+wireguard-y += cookie.o
+wireguard-y += netlink.o generated/netlink.o
+obj-$(CONFIG_WIREGUARD) := wireguard.o

linux-7.2.3/drivers/net/wireguard/allowedips.c

@@ -0,0 +1,424 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include "allowedips.h"
+#include "peer.h"
+
+enum { MAX_ALLOWEDIPS_DEPTH = 129 };
+
+static struct kmem_cache *node_cache;
+
+static void swap_endian(u8 *dst, const u8 *src, u8 bits)
+{
+	if (bits == 32) {
+		*(u32 *)dst = be32_to_cpu(*(const __be32 *)src);
+	} else if (bits == 128) {
+		((u64 *)dst)[0] = get_unaligned_be64(src);
+		((u64 *)dst)[1] = get_unaligned_be64(src + 8);
+	}
+}
+
+static void copy_and_assign_cidr(struct allowedips_node *node, const u8 *src,
+				 u8 cidr, u8 bits)
+{
+	node->cidr = cidr;
+	node->bit_at_a = cidr / 8U;
+#ifdef __LITTLE_ENDIAN
+	node->bit_at_a ^= (bits / 8U - 1U) % 8U;
+#endif
+	node->bit_at_b = 7U - (cidr % 8U);
+	node->bitlen = bits;
+	memcpy(node->bits, src, bits / 8U);
+}
+
+static inline u8 choose(struct allowedips_node *node, const u8 *key)
+{
+	return (key[node->bit_at_a] >> node->bit_at_b) & 1;
+}
+
+static void push_rcu(struct allowedips_node **stack,
+		     struct allowedips_node __rcu *p, unsigned int *len)
+{
+	if (rcu_access_pointer(p)) {
+		if (WARN_ON(IS_ENABLED(DEBUG) && *len >= MAX_ALLOWEDIPS_DEPTH))
+			return;
+		stack[(*len)++] = rcu_dereference_raw(p);
+	}
+}
+
+static void root_free_rcu(struct rcu_head *rcu)
+{
+	struct allowedips_node *node, *stack[MAX_ALLOWEDIPS_DEPTH] = {
+		container_of(rcu, struct allowedips_node, rcu) };
+	unsigned int len = 1;
+
+	while (len > 0 && (node = stack[--len])) {
+		push_rcu(stack, node->bit[0], &len);
+		push_rcu(stack, node->bit[1], &len);
+		kmem_cache_free(node_cache, node);
+	}
+}
+
+static void root_remove_peer_lists(struct allowedips_node *root)
+{
+	struct allowedips_node *node, *stack[MAX_ALLOWEDIPS_DEPTH] = { root };
+	unsigned int len = 1;
+
+	while (len > 0 && (node = stack[--len])) {
+		push_rcu(stack, node->bit[0], &len);
+		push_rcu(stack, node->bit[1], &len);
+		if (rcu_access_pointer(node->peer))
+			list_del(&node->peer_list);
+	}
+}
+
+static unsigned int fls128(u64 a, u64 b)
+{
+	return a ? fls64(a) + 64U : fls64(b);
+}
+
+static u8 common_bits(const struct allowedips_node *node, const u8 *key,
+		      u8 bits)
+{
+	if (bits == 32)
+		return 32U - fls(*(const u32 *)node->bits ^ *(const u32 *)key);
+	else if (bits == 128)
+		return 128U - fls128(
+			*(const u64 *)&node->bits[0] ^ *(const u64 *)&key[0],
+			*(const u64 *)&node->bits[8] ^ *(const u64 *)&key[8]);
+	return 0;
+}
+
+static bool prefix_matches(const struct allowedips_node *node, const u8 *key,
+			   u8 bits)
+{
+	/* This could be much faster if it actually just compared the common
+	 * bits properly, by precomputing a mask bswap(~0 << (32 - cidr)), and
+	 * the rest, but it turns out that common_bits is already super fast on
+	 * modern processors, even taking into account the unfortunate bswap.
+	 * So, we just inline it like this instead.
+	 */
+	return common_bits(node, key, bits) >= node->cidr;
+}
+
+static struct allowedips_node *find_node(struct allowedips_node *trie, u8 bits,
+					 const u8 *key)
+{
+	struct allowedips_node *node = trie, *found = NULL;
+
+	while (node && prefix_matches(node, key, bits)) {
+		if (rcu_access_pointer(node->peer))
+			found = node;
+		if (node->cidr == bits)
+			break;
+		node = rcu_dereference_bh(node->bit[choose(node, key)]);
+	}
+	return found;
+}
+
+/* Returns a strong reference to a peer */
+static struct wg_peer *lookup(struct allowedips_node __rcu *root, u8 bits,
+			      const void *be_ip)
+{
+	/* Aligned so it can be passed to fls/fls64 */
+	u8 ip[16] __aligned(__alignof(u64));
+	struct allowedips_node *node;
+	struct wg_peer *peer = NULL;
+
+	swap_endian(ip, be_ip, bits);
+
+	rcu_read_lock_bh();
+retry:
+	node = find_node(rcu_dereference_bh(root), bits, ip);
+	if (node) {
+		peer = wg_peer_get_maybe_zero(rcu_dereference_bh(node->peer));
+		if (!peer)
+			goto retry;
+	}
+	rcu_read_unlock_bh();
+	return peer;
+}
+
+static bool node_placement(struct allowedips_node __rcu *trie, const u8 *key,
+			   u8 cidr, u8 bits, struct allowedips_node **rnode,
+			   struct mutex *lock)
+{
+	struct allowedips_node *node = rcu_dereference_protected(trie, lockdep_is_held(lock));
+	struct allowedips_node *parent = NULL;
+	bool exact = false;
+
+	while (node && node->cidr <= cidr && prefix_matches(node, key, bits)) {
+		parent = node;
+		if (parent->cidr == cidr) {
+			exact = true;
+			break;
+		}
+		node = rcu_dereference_protected(parent->bit[choose(parent, key)], lockdep_is_held(lock));
+	}
+	*rnode = parent;
+	return exact;
+}
+
+static inline void connect_node(struct allowedips_node __rcu **parent, u8 bit, struct allowedips_node *node)
+{
+	node->parent_bit_packed = (unsigned long)parent | bit;
+	rcu_assign_pointer(*parent, node);
+}
+
+static inline void choose_and_connect_node(struct allowedips_node *parent, struct allowedips_node *node)
+{
+	u8 bit = choose(parent, node->bits);
+	connect_node(&parent->bit[bit], bit, node);
+}
+
+static int add(struct allowedips_node __rcu **trie, u8 bits, const u8 *key,
+	       u8 cidr, struct wg_peer *peer, struct mutex *lock)
+{
+	struct allowedips_node *node, *parent, *down, *newnode;
+
+	if (unlikely(cidr > bits || !peer))
+		return -EINVAL;
+
+	if (!rcu_access_pointer(*trie)) {
+		node = kmem_cache_zalloc(node_cache, GFP_KERNEL);
+		if (unlikely(!node))
+			return -ENOMEM;
+		RCU_INIT_POINTER(node->peer, peer);
+		list_add_tail(&node->peer_list, &peer->allowedips_list);
+		copy_and_assign_cidr(node, key, cidr, bits);
+		connect_node(trie, 2, node);
+		return 0;
+	}
+	if (node_placement(*trie, key, cidr, bits, &node, lock)) {
+		rcu_assign_pointer(node->peer, peer);
+		list_move_tail(&node->peer_list, &peer->allowedips_list);
+		return 0;
+	}
+
+	newnode = kmem_cache_zalloc(node_cache, GFP_KERNEL);
+	if (unlikely(!newnode))
+		return -ENOMEM;
+	RCU_INIT_POINTER(newnode->peer, peer);
+	list_add_tail(&newnode->peer_list, &peer->allowedips_list);
+	copy_and_assign_cidr(newnode, key, cidr, bits);
+
+	if (!node) {
+		down = rcu_dereference_protected(*trie, lockdep_is_held(lock));
+	} else {
+		const u8 bit = choose(node, key);
+		down = rcu_dereference_protected(node->bit[bit], lockdep_is_held(lock));
+		if (!down) {
+			connect_node(&node->bit[bit], bit, newnode);
+			return 0;
+		}
+	}
+	cidr = min(cidr, common_bits(down, key, bits));
+	parent = node;
+
+	if (newnode->cidr == cidr) {
+		choose_and_connect_node(newnode, down);
+		if (!parent)
+			connect_node(trie, 2, newnode);
+		else
+			choose_and_connect_node(parent, newnode);
+		return 0;
+	}
+
+	node = kmem_cache_zalloc(node_cache, GFP_KERNEL);
+	if (unlikely(!node)) {
+		list_del(&newnode->peer_list);
+		kmem_cache_free(node_cache, newnode);
+		return -ENOMEM;
+	}
+	INIT_LIST_HEAD(&node->peer_list);
+	copy_and_assign_cidr(node, newnode->bits, cidr, bits);
+
+	choose_and_connect_node(node, down);
+	choose_and_connect_node(node, newnode);
+	if (!parent)
+		connect_node(trie, 2, node);
+	else
+		choose_and_connect_node(parent, node);
+	return 0;
+}
+
+static void remove_node(struct allowedips_node *node, struct mutex *lock)
+{
+	struct allowedips_node *child, **parent_bit, *parent;
+	bool free_parent;
+
+	list_del_init(&node->peer_list);
+	RCU_INIT_POINTER(node->peer, NULL);
+	if (node->bit[0] && node->bit[1])
+		return;
+	child = rcu_dereference_protected(node->bit[!rcu_access_pointer(node->bit[0])],
+					  lockdep_is_held(lock));
+	if (child)
+		child->parent_bit_packed = node->parent_bit_packed;
+	parent_bit = (struct allowedips_node **)(node->parent_bit_packed & ~3UL);
+	*parent_bit = child;
+	parent = (void *)parent_bit -
+			offsetof(struct allowedips_node, bit[node->parent_bit_packed & 1]);
+	free_parent = !rcu_access_pointer(node->bit[0]) && !rcu_access_pointer(node->bit[1]) &&
+			(node->parent_bit_packed & 3) <= 1 && !rcu_access_pointer(parent->peer);
+	if (free_parent)
+		child = rcu_dereference_protected(parent->bit[!(node->parent_bit_packed & 1)],
+						  lockdep_is_held(lock));
+	kfree_rcu(node, rcu);
+	if (!free_parent)
+		return;
+	if (child)
+		child->parent_bit_packed = parent->parent_bit_packed;
+	*(struct allowedips_node **)(parent->parent_bit_packed & ~3UL) = child;
+	kfree_rcu(parent, rcu);
+}
+
+static int remove(struct allowedips_node __rcu **trie, u8 bits, const u8 *key,
+		  u8 cidr, struct wg_peer *peer, struct mutex *lock)
+{
+	struct allowedips_node *node;
+
+	if (unlikely(cidr > bits))
+		return -EINVAL;
+	if (!rcu_access_pointer(*trie) || !node_placement(*trie, key, cidr, bits, &node, lock) ||
+	    peer != rcu_access_pointer(node->peer))
+		return 0;
+
+	remove_node(node, lock);
+	return 0;
+}
+
+void wg_allowedips_init(struct allowedips *table)
+{
+	table->root4 = table->root6 = NULL;
+	table->seq = 1;
+}
+
+void wg_allowedips_free(struct allowedips *table, struct mutex *lock)
+{
+	struct allowedips_node __rcu *old4 = table->root4, *old6 = table->root6;
+
+	++table->seq;
+	RCU_INIT_POINTER(table->root4, NULL);
+	RCU_INIT_POINTER(table->root6, NULL);
+	if (rcu_access_pointer(old4)) {
+		struct allowedips_node *node = rcu_dereference_protected(old4,
+							lockdep_is_held(lock));
+
+		root_remove_peer_lists(node);
+		call_rcu(&node->rcu, root_free_rcu);
+	}
+	if (rcu_access_pointer(old6)) {
+		struct allowedips_node *node = rcu_dereference_protected(old6,
+							lockdep_is_held(lock));
+
+		root_remove_peer_lists(node);
+		call_rcu(&node->rcu, root_free_rcu);
+	}
+}
+
+int wg_allowedips_insert_v4(struct allowedips *table, const struct in_addr *ip,
+			    u8 cidr, struct wg_peer *peer, struct mutex *lock)
+{
+	/* Aligned so it can be passed to fls */
+	u8 key[4] __aligned(__alignof(u32));
+
+	++table->seq;
+	swap_endian(key, (const u8 *)ip, 32);
+	return add(&table->root4, 32, key, cidr, peer, lock);
+}
+
+int wg_allowedips_insert_v6(struct allowedips *table, const struct in6_addr *ip,
+			    u8 cidr, struct wg_peer *peer, struct mutex *lock)
+{
+	/* Aligned so it can be passed to fls64 */
+	u8 key[16] __aligned(__alignof(u64));
+
+	++table->seq;
+	swap_endian(key, (const u8 *)ip, 128);
+	return add(&table->root6, 128, key, cidr, peer, lock);
+}
+
+int wg_allowedips_remove_v4(struct allowedips *table, const struct in_addr *ip,
+			    u8 cidr, struct wg_peer *peer, struct mutex *lock)
+{
+	/* Aligned so it can be passed to fls */
+	u8 key[4] __aligned(__alignof(u32));
+
+	++table->seq;
+	swap_endian(key, (const u8 *)ip, 32);
+	return remove(&table->root4, 32, key, cidr, peer, lock);
+}
+
+int wg_allowedips_remove_v6(struct allowedips *table, const struct in6_addr *ip,
+			    u8 cidr, struct wg_peer *peer, struct mutex *lock)
+{
+	/* Aligned so it can be passed to fls64 */
+	u8 key[16] __aligned(__alignof(u64));
+
+	++table->seq;
+	swap_endian(key, (const u8 *)ip, 128);
+	return remove(&table->root6, 128, key, cidr, peer, lock);
+}
+
+void wg_allowedips_remove_by_peer(struct allowedips *table,
+				  struct wg_peer *peer, struct mutex *lock)
+{
+	struct allowedips_node *node, *tmp;
+
+	if (list_empty(&peer->allowedips_list))
+		return;
+	++table->seq;
+	list_for_each_entry_safe(node, tmp, &peer->allowedips_list, peer_list)
+		remove_node(node, lock);
+}
+
+int wg_allowedips_read_node(struct allowedips_node *node, u8 ip[16], u8 *cidr)
+{
+	const unsigned int cidr_bytes = DIV_ROUND_UP(node->cidr, 8U);
+	swap_endian(ip, node->bits, node->bitlen);
+	memset(ip + cidr_bytes, 0, node->bitlen / 8U - cidr_bytes);
+	if (node->cidr)
+		ip[cidr_bytes - 1U] &= ~0U << (-node->cidr % 8U);
+
+	*cidr = node->cidr;
+	return node->bitlen == 32 ? AF_INET : AF_INET6;
+}
+
+/* Returns a strong reference to a peer */
+struct wg_peer *wg_allowedips_lookup_dst(struct allowedips *table,
+					 struct sk_buff *skb)
+{
+	if (skb->protocol == htons(ETH_P_IP))
+		return lookup(table->root4, 32, &ip_hdr(skb)->daddr);
+	else if (skb->protocol == htons(ETH_P_IPV6))
+		return lookup(table->root6, 128, &ipv6_hdr(skb)->daddr);
+	return NULL;
+}
+
+/* Returns a strong reference to a peer */
+struct wg_peer *wg_allowedips_lookup_src(struct allowedips *table,
+					 struct sk_buff *skb)
+{
+	if (skb->protocol == htons(ETH_P_IP))
+		return lookup(table->root4, 32, &ip_hdr(skb)->saddr);
+	else if (skb->protocol == htons(ETH_P_IPV6))
+		return lookup(table->root6, 128, &ipv6_hdr(skb)->saddr);
+	return NULL;
+}
+
+int __init wg_allowedips_slab_init(void)
+{
+	node_cache = KMEM_CACHE(allowedips_node, 0);
+	return node_cache ? 0 : -ENOMEM;
+}
+
+void wg_allowedips_slab_uninit(void)
+{
+	rcu_barrier();
+	kmem_cache_destroy(node_cache);
+}
+
+#include "selftest/allowedips.c"

linux-7.2.3/drivers/net/wireguard/allowedips.h

@@ -0,0 +1,63 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#ifndef _WG_ALLOWEDIPS_H
+#define _WG_ALLOWEDIPS_H
+
+#include <linux/mutex.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+
+struct wg_peer;
+
+struct allowedips_node {
+	struct wg_peer __rcu *peer;
+	struct allowedips_node __rcu *bit[2];
+	u8 cidr, bit_at_a, bit_at_b, bitlen;
+	u8 bits[16] __aligned(__alignof(u64));
+
+	/* Keep rarely used members at bottom to be beyond cache line. */
+	unsigned long parent_bit_packed;
+	union {
+		struct list_head peer_list;
+		struct rcu_head rcu;
+	};
+};
+
+struct allowedips {
+	struct allowedips_node __rcu *root4;
+	struct allowedips_node __rcu *root6;
+	u64 seq;
+} __aligned(4); /* We pack the lower 2 bits of &root, but m68k only gives 16-bit alignment. */
+
+void wg_allowedips_init(struct allowedips *table);
+void wg_allowedips_free(struct allowedips *table, struct mutex *mutex);
+int wg_allowedips_insert_v4(struct allowedips *table, const struct in_addr *ip,
+			    u8 cidr, struct wg_peer *peer, struct mutex *lock);
+int wg_allowedips_insert_v6(struct allowedips *table, const struct in6_addr *ip,
+			    u8 cidr, struct wg_peer *peer, struct mutex *lock);
+int wg_allowedips_remove_v4(struct allowedips *table, const struct in_addr *ip,
+			    u8 cidr, struct wg_peer *peer, struct mutex *lock);
+int wg_allowedips_remove_v6(struct allowedips *table, const struct in6_addr *ip,
+			    u8 cidr, struct wg_peer *peer, struct mutex *lock);
+void wg_allowedips_remove_by_peer(struct allowedips *table,
+				  struct wg_peer *peer, struct mutex *lock);
+/* The ip input pointer should be __aligned(__alignof(u64))) */
+int wg_allowedips_read_node(struct allowedips_node *node, u8 ip[16], u8 *cidr);
+
+/* These return a strong reference to a peer: */
+struct wg_peer *wg_allowedips_lookup_dst(struct allowedips *table,
+					 struct sk_buff *skb);
+struct wg_peer *wg_allowedips_lookup_src(struct allowedips *table,
+					 struct sk_buff *skb);
+
+#ifdef DEBUG
+bool wg_allowedips_selftest(void);
+#endif
+
+int wg_allowedips_slab_init(void);
+void wg_allowedips_slab_uninit(void);
+
+#endif /* _WG_ALLOWEDIPS_H */

linux-7.2.3/drivers/net/wireguard/cookie.c

@@ -0,0 +1,236 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include "cookie.h"
+#include "peer.h"
+#include "device.h"
+#include "messages.h"
+#include "ratelimiter.h"
+#include "timers.h"
+
+#include <crypto/blake2s.h>
+#include <crypto/chacha20poly1305.h>
+#include <crypto/utils.h>
+
+#include <net/ipv6.h>
+
+void wg_cookie_checker_init(struct cookie_checker *checker,
+			    struct wg_device *wg)
+{
+	init_rwsem(&checker->secret_lock);
+	checker->secret_birthdate = ktime_get_coarse_boottime_ns();
+	get_random_bytes(checker->secret, NOISE_HASH_LEN);
+	checker->device = wg;
+}
+
+enum { COOKIE_KEY_LABEL_LEN = 8 };
+static const u8 mac1_key_label[COOKIE_KEY_LABEL_LEN] __nonstring = "mac1----";
+static const u8 cookie_key_label[COOKIE_KEY_LABEL_LEN] __nonstring = "cookie--";
+
+static void precompute_key(u8 key[NOISE_SYMMETRIC_KEY_LEN],
+			   const u8 pubkey[NOISE_PUBLIC_KEY_LEN],
+			   const u8 label[COOKIE_KEY_LABEL_LEN])
+{
+	struct blake2s_ctx blake;
+
+	blake2s_init(&blake, NOISE_SYMMETRIC_KEY_LEN);
+	blake2s_update(&blake, label, COOKIE_KEY_LABEL_LEN);
+	blake2s_update(&blake, pubkey, NOISE_PUBLIC_KEY_LEN);
+	blake2s_final(&blake, key);
+}
+
+/* Must hold peer->handshake.static_identity->lock */
+void wg_cookie_checker_precompute_device_keys(struct cookie_checker *checker)
+{
+	if (likely(checker->device->static_identity.has_identity)) {
+		precompute_key(checker->cookie_encryption_key,
+			       checker->device->static_identity.static_public,
+			       cookie_key_label);
+		precompute_key(checker->message_mac1_key,
+			       checker->device->static_identity.static_public,
+			       mac1_key_label);
+	} else {
+		memset(checker->cookie_encryption_key, 0,
+		       NOISE_SYMMETRIC_KEY_LEN);
+		memset(checker->message_mac1_key, 0, NOISE_SYMMETRIC_KEY_LEN);
+	}
+}
+
+void wg_cookie_checker_precompute_peer_keys(struct wg_peer *peer)
+{
+	precompute_key(peer->latest_cookie.cookie_decryption_key,
+		       peer->handshake.remote_static, cookie_key_label);
+	precompute_key(peer->latest_cookie.message_mac1_key,
+		       peer->handshake.remote_static, mac1_key_label);
+}
+
+void wg_cookie_init(struct cookie *cookie)
+{
+	memset(cookie, 0, sizeof(*cookie));
+	init_rwsem(&cookie->lock);
+}
+
+static void compute_mac1(u8 mac1[COOKIE_LEN], const void *message, size_t len,
+			 const u8 key[NOISE_SYMMETRIC_KEY_LEN])
+{
+	len = len - sizeof(struct message_macs) +
+	      offsetof(struct message_macs, mac1);
+	blake2s(key, NOISE_SYMMETRIC_KEY_LEN, message, len, mac1, COOKIE_LEN);
+}
+
+static void compute_mac2(u8 mac2[COOKIE_LEN], const void *message, size_t len,
+			 const u8 cookie[COOKIE_LEN])
+{
+	len = len - sizeof(struct message_macs) +
+	      offsetof(struct message_macs, mac2);
+	blake2s(cookie, COOKIE_LEN, message, len, mac2, COOKIE_LEN);
+}
+
+static void make_cookie(u8 cookie[COOKIE_LEN], struct sk_buff *skb,
+			struct cookie_checker *checker)
+{
+	struct blake2s_ctx blake;
+
+	if (wg_birthdate_has_expired(checker->secret_birthdate,
+				     COOKIE_SECRET_MAX_AGE)) {
+		down_write(&checker->secret_lock);
+		checker->secret_birthdate = ktime_get_coarse_boottime_ns();
+		get_random_bytes(checker->secret, NOISE_HASH_LEN);
+		up_write(&checker->secret_lock);
+	}
+
+	down_read(&checker->secret_lock);
+
+	blake2s_init_key(&blake, COOKIE_LEN, checker->secret, NOISE_HASH_LEN);
+	if (skb->protocol == htons(ETH_P_IP))
+		blake2s_update(&blake, (u8 *)&ip_hdr(skb)->saddr,
+			       sizeof(struct in_addr));
+	else if (skb->protocol == htons(ETH_P_IPV6))
+		blake2s_update(&blake, (u8 *)&ipv6_hdr(skb)->saddr,
+			       sizeof(struct in6_addr));
+	blake2s_update(&blake, (u8 *)&udp_hdr(skb)->source, sizeof(__be16));
+	blake2s_final(&blake, cookie);
+
+	up_read(&checker->secret_lock);
+}
+
+enum cookie_mac_state wg_cookie_validate_packet(struct cookie_checker *checker,
+						struct sk_buff *skb,
+						bool check_cookie)
+{
+	struct message_macs *macs = (struct message_macs *)
+		(skb->data + skb->len - sizeof(*macs));
+	enum cookie_mac_state ret;
+	u8 computed_mac[COOKIE_LEN];
+	u8 cookie[COOKIE_LEN];
+
+	ret = INVALID_MAC;
+	compute_mac1(computed_mac, skb->data, skb->len,
+		     checker->message_mac1_key);
+	if (crypto_memneq(computed_mac, macs->mac1, COOKIE_LEN))
+		goto out;
+
+	ret = VALID_MAC_BUT_NO_COOKIE;
+
+	if (!check_cookie)
+		goto out;
+
+	make_cookie(cookie, skb, checker);
+
+	compute_mac2(computed_mac, skb->data, skb->len, cookie);
+	if (crypto_memneq(computed_mac, macs->mac2, COOKIE_LEN))
+		goto out;
+
+	ret = VALID_MAC_WITH_COOKIE_BUT_RATELIMITED;
+	if (!wg_ratelimiter_allow(skb, dev_net(checker->device->dev)))
+		goto out;
+
+	ret = VALID_MAC_WITH_COOKIE;
+
+out:
+	return ret;
+}
+
+void wg_cookie_add_mac_to_packet(void *message, size_t len,
+				 struct wg_peer *peer)
+{
+	struct message_macs *macs = (struct message_macs *)
+		((u8 *)message + len - sizeof(*macs));
+
+	down_write(&peer->latest_cookie.lock);
+	compute_mac1(macs->mac1, message, len,
+		     peer->latest_cookie.message_mac1_key);
+	memcpy(peer->latest_cookie.last_mac1_sent, macs->mac1, COOKIE_LEN);
+	peer->latest_cookie.have_sent_mac1 = true;
+	up_write(&peer->latest_cookie.lock);
+
+	down_read(&peer->latest_cookie.lock);
+	if (peer->latest_cookie.is_valid &&
+	    !wg_birthdate_has_expired(peer->latest_cookie.birthdate,
+				COOKIE_SECRET_MAX_AGE - COOKIE_SECRET_LATENCY))
+		compute_mac2(macs->mac2, message, len,
+			     peer->latest_cookie.cookie);
+	else
+		memset(macs->mac2, 0, COOKIE_LEN);
+	up_read(&peer->latest_cookie.lock);
+}
+
+void wg_cookie_message_create(struct message_handshake_cookie *dst,
+			      struct sk_buff *skb, __le32 index,
+			      struct cookie_checker *checker)
+{
+	struct message_macs *macs = (struct message_macs *)
+		((u8 *)skb->data + skb->len - sizeof(*macs));
+	u8 cookie[COOKIE_LEN];
+
+	dst->header.type = cpu_to_le32(MESSAGE_HANDSHAKE_COOKIE);
+	dst->receiver_index = index;
+	get_random_bytes_wait(dst->nonce, COOKIE_NONCE_LEN);
+
+	make_cookie(cookie, skb, checker);
+	xchacha20poly1305_encrypt(dst->encrypted_cookie, cookie, COOKIE_LEN,
+				  macs->mac1, COOKIE_LEN, dst->nonce,
+				  checker->cookie_encryption_key);
+}
+
+void wg_cookie_message_consume(struct message_handshake_cookie *src,
+			       struct wg_device *wg)
+{
+	struct wg_peer *peer = NULL;
+	u8 cookie[COOKIE_LEN];
+	bool ret;
+
+	if (unlikely(!wg_index_hashtable_lookup(wg->index_hashtable,
+						INDEX_HASHTABLE_HANDSHAKE |
+						INDEX_HASHTABLE_KEYPAIR,
+						src->receiver_index, &peer)))
+		return;
+
+	down_read(&peer->latest_cookie.lock);
+	if (unlikely(!peer->latest_cookie.have_sent_mac1)) {
+		up_read(&peer->latest_cookie.lock);
+		goto out;
+	}
+	ret = xchacha20poly1305_decrypt(
+		cookie, src->encrypted_cookie, sizeof(src->encrypted_cookie),
+		peer->latest_cookie.last_mac1_sent, COOKIE_LEN, src->nonce,
+		peer->latest_cookie.cookie_decryption_key);
+	up_read(&peer->latest_cookie.lock);
+
+	if (ret) {
+		down_write(&peer->latest_cookie.lock);
+		memcpy(peer->latest_cookie.cookie, cookie, COOKIE_LEN);
+		peer->latest_cookie.birthdate = ktime_get_coarse_boottime_ns();
+		peer->latest_cookie.is_valid = true;
+		peer->latest_cookie.have_sent_mac1 = false;
+		up_write(&peer->latest_cookie.lock);
+	} else {
+		net_dbg_ratelimited("%s: Could not decrypt invalid cookie response\n",
+				    wg->dev->name);
+	}
+
+out:
+	wg_peer_put(peer);
+}

linux-7.2.3/drivers/net/wireguard/cookie.h

@@ -0,0 +1,59 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#ifndef _WG_COOKIE_H
+#define _WG_COOKIE_H
+
+#include "messages.h"
+#include <linux/rwsem.h>
+
+struct wg_peer;
+
+struct cookie_checker {
+	u8 secret[NOISE_HASH_LEN];
+	u8 cookie_encryption_key[NOISE_SYMMETRIC_KEY_LEN];
+	u8 message_mac1_key[NOISE_SYMMETRIC_KEY_LEN];
+	u64 secret_birthdate;
+	struct rw_semaphore secret_lock;
+	struct wg_device *device;
+};
+
+struct cookie {
+	u64 birthdate;
+	bool is_valid;
+	u8 cookie[COOKIE_LEN];
+	bool have_sent_mac1;
+	u8 last_mac1_sent[COOKIE_LEN];
+	u8 cookie_decryption_key[NOISE_SYMMETRIC_KEY_LEN];
+	u8 message_mac1_key[NOISE_SYMMETRIC_KEY_LEN];
+	struct rw_semaphore lock;
+};
+
+enum cookie_mac_state {
+	INVALID_MAC,
+	VALID_MAC_BUT_NO_COOKIE,
+	VALID_MAC_WITH_COOKIE_BUT_RATELIMITED,
+	VALID_MAC_WITH_COOKIE
+};
+
+void wg_cookie_checker_init(struct cookie_checker *checker,
+			    struct wg_device *wg);
+void wg_cookie_checker_precompute_device_keys(struct cookie_checker *checker);
+void wg_cookie_checker_precompute_peer_keys(struct wg_peer *peer);
+void wg_cookie_init(struct cookie *cookie);
+
+enum cookie_mac_state wg_cookie_validate_packet(struct cookie_checker *checker,
+						struct sk_buff *skb,
+						bool check_cookie);
+void wg_cookie_add_mac_to_packet(void *message, size_t len,
+				 struct wg_peer *peer);
+
+void wg_cookie_message_create(struct message_handshake_cookie *src,
+			      struct sk_buff *skb, __le32 index,
+			      struct cookie_checker *checker);
+void wg_cookie_message_consume(struct message_handshake_cookie *src,
+			       struct wg_device *wg);
+
+#endif /* _WG_COOKIE_H */

linux-7.2.3/drivers/net/wireguard/device.c

@@ -0,0 +1,475 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include "queueing.h"
+#include "socket.h"
+#include "timers.h"
+#include "device.h"
+#include "ratelimiter.h"
+#include "peer.h"
+#include "messages.h"
+
+#include <linux/module.h>
+#include <linux/rtnetlink.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/inetdevice.h>
+#include <linux/if_arp.h>
+#include <linux/icmp.h>
+#include <linux/suspend.h>
+#include <net/dst_metadata.h>
+#include <net/gso.h>
+#include <net/icmp.h>
+#include <net/rtnetlink.h>
+#include <net/ip_tunnels.h>
+#include <net/addrconf.h>
+
+static LIST_HEAD(device_list);
+
+static int wg_open(struct net_device *dev)
+{
+	struct in_device *dev_v4 = __in_dev_get_rtnl(dev);
+	struct inet6_dev *dev_v6 = __in6_dev_get(dev);
+	struct wg_device *wg = netdev_priv(dev);
+	struct wg_peer *peer;
+	int ret;
+
+	if (dev_v4) {
+		/* At some point we might put this check near the ip_rt_send_
+		 * redirect call of ip_forward in net/ipv4/ip_forward.c, similar
+		 * to the current secpath check.
+		 */
+		IN_DEV_CONF_SET(dev_v4, SEND_REDIRECTS, false);
+		IPV4_DEVCONF_ALL(dev_net(dev), SEND_REDIRECTS) = false;
+	}
+	if (dev_v6)
+		dev_v6->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_NONE;
+
+	mutex_lock(&wg->device_update_lock);
+	ret = wg_socket_init(wg, wg->incoming_port);
+	if (ret < 0)
+		goto out;
+	list_for_each_entry(peer, &wg->peer_list, peer_list) {
+		wg_packet_send_staged_packets(peer);
+		if (peer->persistent_keepalive_interval)
+			wg_packet_send_keepalive(peer);
+	}
+out:
+	mutex_unlock(&wg->device_update_lock);
+	return ret;
+}
+
+static int wg_pm_notification(struct notifier_block *nb, unsigned long action, void *data)
+{
+	struct wg_device *wg;
+	struct wg_peer *peer;
+
+	/* If the machine is constantly suspending and resuming, as part of
+	 * its normal operation rather than as a somewhat rare event, then we
+	 * don't actually want to clear keys.
+	 */
+	if (IS_ENABLED(CONFIG_PM_AUTOSLEEP) ||
+	    IS_ENABLED(CONFIG_PM_USERSPACE_AUTOSLEEP))
+		return 0;
+
+	if (action != PM_HIBERNATION_PREPARE && action != PM_SUSPEND_PREPARE)
+		return 0;
+
+	rtnl_lock();
+	list_for_each_entry(wg, &device_list, device_list) {
+		mutex_lock(&wg->device_update_lock);
+		list_for_each_entry(peer, &wg->peer_list, peer_list) {
+			timer_delete(&peer->timer_zero_key_material);
+			wg_noise_handshake_clear(&peer->handshake);
+			wg_noise_keypairs_clear(&peer->keypairs);
+		}
+		mutex_unlock(&wg->device_update_lock);
+	}
+	rtnl_unlock();
+	rcu_barrier();
+	return 0;
+}
+
+static struct notifier_block pm_notifier = { .notifier_call = wg_pm_notification };
+
+static int wg_vm_notification(struct notifier_block *nb, unsigned long action, void *data)
+{
+	struct wg_device *wg;
+	struct wg_peer *peer;
+
+	rtnl_lock();
+	list_for_each_entry(wg, &device_list, device_list) {
+		mutex_lock(&wg->device_update_lock);
+		list_for_each_entry(peer, &wg->peer_list, peer_list)
+			wg_noise_expire_current_peer_keypairs(peer);
+		mutex_unlock(&wg->device_update_lock);
+	}
+	rtnl_unlock();
+	return 0;
+}
+
+static struct notifier_block vm_notifier = { .notifier_call = wg_vm_notification };
+
+static int wg_stop(struct net_device *dev)
+{
+	struct wg_device *wg = netdev_priv(dev);
+	struct wg_peer *peer;
+	struct sk_buff *skb;
+
+	mutex_lock(&wg->device_update_lock);
+	list_for_each_entry(peer, &wg->peer_list, peer_list) {
+		wg_packet_purge_staged_packets(peer);
+		wg_timers_stop(peer);
+		wg_noise_handshake_clear(&peer->handshake);
+		wg_noise_keypairs_clear(&peer->keypairs);
+		wg_noise_reset_last_sent_handshake(&peer->last_sent_handshake);
+	}
+	mutex_unlock(&wg->device_update_lock);
+	while ((skb = ptr_ring_consume(&wg->handshake_queue.ring)) != NULL)
+		kfree_skb(skb);
+	atomic_set(&wg->handshake_queue_len, 0);
+	wg_socket_reinit(wg, NULL, NULL);
+	return 0;
+}
+
+static netdev_tx_t wg_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct wg_device *wg = netdev_priv(dev);
+	struct sk_buff_head packets;
+	struct wg_peer *peer;
+	struct sk_buff *next;
+	sa_family_t family;
+	u32 mtu;
+	int ret;
+
+	if (unlikely(!wg_check_packet_protocol(skb))) {
+		ret = -EPROTONOSUPPORT;
+		net_dbg_ratelimited("%s: Invalid IP packet\n", dev->name);
+		goto err;
+	}
+
+	peer = wg_allowedips_lookup_dst(&wg->peer_allowedips, skb);
+	if (unlikely(!peer)) {
+		ret = -ENOKEY;
+		if (skb->protocol == htons(ETH_P_IP))
+			net_dbg_ratelimited("%s: No peer has allowed IPs matching %pI4\n",
+					    dev->name, &ip_hdr(skb)->daddr);
+		else if (skb->protocol == htons(ETH_P_IPV6))
+			net_dbg_ratelimited("%s: No peer has allowed IPs matching %pI6\n",
+					    dev->name, &ipv6_hdr(skb)->daddr);
+		goto err_icmp;
+	}
+
+	family = READ_ONCE(peer->endpoint.addr.sa_family);
+	if (unlikely(family != AF_INET && family != AF_INET6)) {
+		ret = -EDESTADDRREQ;
+		net_dbg_ratelimited("%s: No valid endpoint has been configured or discovered for peer %llu\n",
+				    dev->name, peer->internal_id);
+		goto err_peer;
+	}
+
+	mtu = skb_valid_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;
+
+	__skb_queue_head_init(&packets);
+	if (!skb_is_gso(skb)) {
+		skb_mark_not_on_list(skb);
+	} else {
+		struct sk_buff *segs = skb_gso_segment(skb, 0);
+
+		if (IS_ERR(segs)) {
+			ret = PTR_ERR(segs);
+			goto err_peer;
+		}
+		dev_kfree_skb(skb);
+		skb = segs;
+	}
+
+	skb_list_walk_safe(skb, skb, next) {
+		skb_mark_not_on_list(skb);
+
+		skb = skb_share_check(skb, GFP_ATOMIC);
+		if (unlikely(!skb))
+			continue;
+
+		/* We only need to keep the original dst around for icmp,
+		 * so at this point we're in a position to drop it.
+		 */
+		skb_dst_drop(skb);
+
+		PACKET_CB(skb)->mtu = mtu;
+
+		__skb_queue_tail(&packets, skb);
+	}
+
+	spin_lock_bh(&peer->staged_packet_queue.lock);
+	/* If the queue is getting too big, we start removing the oldest packets
+	 * until it's small again. We do this before adding the new packet, so
+	 * we don't remove GSO segments that are in excess.
+	 */
+	while (skb_queue_len(&peer->staged_packet_queue) > MAX_STAGED_PACKETS) {
+		dev_kfree_skb(__skb_dequeue(&peer->staged_packet_queue));
+		DEV_STATS_INC(dev, tx_dropped);
+	}
+	skb_queue_splice_tail(&packets, &peer->staged_packet_queue);
+	spin_unlock_bh(&peer->staged_packet_queue.lock);
+
+	wg_packet_send_staged_packets(peer);
+
+	wg_peer_put(peer);
+	return NETDEV_TX_OK;
+
+err_peer:
+	wg_peer_put(peer);
+err_icmp:
+	if (skb->protocol == htons(ETH_P_IP))
+		icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
+	else if (skb->protocol == htons(ETH_P_IPV6))
+		icmpv6_ndo_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
+err:
+	DEV_STATS_INC(dev, tx_errors);
+	kfree_skb(skb);
+	return ret;
+}
+
+static const struct net_device_ops netdev_ops = {
+	.ndo_open		= wg_open,
+	.ndo_stop		= wg_stop,
+	.ndo_start_xmit		= wg_xmit,
+};
+
+static void wg_destruct(struct net_device *dev)
+{
+	struct wg_device *wg = netdev_priv(dev);
+
+	rtnl_lock();
+	list_del(&wg->device_list);
+	rtnl_unlock();
+	mutex_lock(&wg->device_update_lock);
+	rcu_assign_pointer(wg->creating_net, NULL);
+	wg->incoming_port = 0;
+	wg_socket_reinit(wg, NULL, NULL);
+	/* The final references are cleared in the below calls to destroy_workqueue. */
+	wg_peer_remove_all(wg);
+	destroy_workqueue(wg->handshake_receive_wq);
+	destroy_workqueue(wg->handshake_send_wq);
+	destroy_workqueue(wg->packet_crypt_wq);
+	wg_packet_queue_free(&wg->handshake_queue, true);
+	wg_packet_queue_free(&wg->decrypt_queue, false);
+	wg_packet_queue_free(&wg->encrypt_queue, false);
+	rcu_barrier(); /* Wait for all the peers to be actually freed. */
+	wg_ratelimiter_uninit();
+	memzero_explicit(&wg->static_identity, sizeof(wg->static_identity));
+	kvfree(wg->index_hashtable);
+	kvfree(wg->peer_hashtable);
+	mutex_unlock(&wg->device_update_lock);
+
+	pr_debug("%s: Interface destroyed\n", dev->name);
+	free_netdev(dev);
+}
+
+static const struct device_type device_type = { .name = KBUILD_MODNAME };
+
+static void wg_setup(struct net_device *dev)
+{
+	struct wg_device *wg = netdev_priv(dev);
+	enum { WG_NETDEV_FEATURES = NETIF_F_HW_CSUM | NETIF_F_RXCSUM |
+				    NETIF_F_SG | NETIF_F_GSO |
+				    NETIF_F_GSO_SOFTWARE | NETIF_F_HIGHDMA };
+	const int overhead = MESSAGE_MINIMUM_LENGTH + sizeof(struct udphdr) +
+			     max(sizeof(struct ipv6hdr), sizeof(struct iphdr));
+
+	dev->netdev_ops = &netdev_ops;
+	dev->header_ops = &ip_tunnel_header_ops;
+	dev->hard_header_len = 0;
+	dev->addr_len = 0;
+	dev->needed_headroom = DATA_PACKET_HEAD_ROOM;
+	dev->needed_tailroom = noise_encrypted_len(MESSAGE_PADDING_MULTIPLE);
+	dev->type = ARPHRD_NONE;
+	dev->flags = IFF_POINTOPOINT | IFF_NOARP;
+	dev->priv_flags |= IFF_NO_QUEUE;
+	dev->lltx = true;
+	dev->features |= WG_NETDEV_FEATURES;
+	dev->hw_features |= WG_NETDEV_FEATURES;
+	dev->hw_enc_features |= WG_NETDEV_FEATURES;
+	dev->mtu = ETH_DATA_LEN - overhead;
+	dev->max_mtu = round_down(INT_MAX, MESSAGE_PADDING_MULTIPLE) - overhead;
+	dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
+
+	SET_NETDEV_DEVTYPE(dev, &device_type);
+
+	/* We need to keep the dst around in case of icmp replies. */
+	netif_keep_dst(dev);
+
+	netif_set_tso_max_size(dev, GSO_MAX_SIZE);
+
+	wg->dev = dev;
+}
+
+static int wg_newlink(struct net_device *dev,
+		      struct rtnl_newlink_params *params,
+		      struct netlink_ext_ack *extack)
+{
+	struct net *link_net = rtnl_newlink_link_net(params);
+	struct wg_device *wg = netdev_priv(dev);
+	int ret = -ENOMEM;
+
+	rcu_assign_pointer(wg->creating_net, link_net);
+	init_rwsem(&wg->static_identity.lock);
+	mutex_init(&wg->socket_update_lock);
+	mutex_init(&wg->device_update_lock);
+	wg_allowedips_init(&wg->peer_allowedips);
+	wg_cookie_checker_init(&wg->cookie_checker, wg);
+	INIT_LIST_HEAD(&wg->peer_list);
+	wg->device_update_gen = 1;
+
+	wg->peer_hashtable = wg_pubkey_hashtable_alloc();
+	if (!wg->peer_hashtable)
+		return ret;
+
+	wg->index_hashtable = wg_index_hashtable_alloc();
+	if (!wg->index_hashtable)
+		goto err_free_peer_hashtable;
+
+	wg->handshake_receive_wq = alloc_workqueue("wg-kex-%s",
+			WQ_CPU_INTENSIVE | WQ_FREEZABLE | WQ_PERCPU, 0,
+			dev->name);
+	if (!wg->handshake_receive_wq)
+		goto err_free_index_hashtable;
+
+	wg->handshake_send_wq = alloc_workqueue("wg-kex-%s",
+			WQ_UNBOUND | WQ_FREEZABLE, 0, dev->name);
+	if (!wg->handshake_send_wq)
+		goto err_destroy_handshake_receive;
+
+	wg->packet_crypt_wq = alloc_workqueue("wg-crypt-%s",
+			WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_PERCPU, 0,
+			dev->name);
+	if (!wg->packet_crypt_wq)
+		goto err_destroy_handshake_send;
+
+	ret = wg_packet_queue_init(&wg->encrypt_queue, wg_packet_encrypt_worker,
+				   MAX_QUEUED_PACKETS);
+	if (ret < 0)
+		goto err_destroy_packet_crypt;
+
+	ret = wg_packet_queue_init(&wg->decrypt_queue, wg_packet_decrypt_worker,
+				   MAX_QUEUED_PACKETS);
+	if (ret < 0)
+		goto err_free_encrypt_queue;
+
+	ret = wg_packet_queue_init(&wg->handshake_queue, wg_packet_handshake_receive_worker,
+				   MAX_QUEUED_INCOMING_HANDSHAKES);
+	if (ret < 0)
+		goto err_free_decrypt_queue;
+
+	ret = wg_ratelimiter_init();
+	if (ret < 0)
+		goto err_free_handshake_queue;
+
+	netif_threaded_enable(dev);
+	ret = register_netdevice(dev);
+	if (ret < 0)
+		goto err_uninit_ratelimiter;
+
+	list_add(&wg->device_list, &device_list);
+
+	/* We wait until the end to assign priv_destructor, so that
+	 * register_netdevice doesn't call it for us if it fails.
+	 */
+	dev->priv_destructor = wg_destruct;
+
+	pr_debug("%s: Interface created\n", dev->name);
+	return ret;
+
+err_uninit_ratelimiter:
+	wg_ratelimiter_uninit();
+err_free_handshake_queue:
+	wg_packet_queue_free(&wg->handshake_queue, false);
+err_free_decrypt_queue:
+	wg_packet_queue_free(&wg->decrypt_queue, false);
+err_free_encrypt_queue:
+	wg_packet_queue_free(&wg->encrypt_queue, false);
+err_destroy_packet_crypt:
+	destroy_workqueue(wg->packet_crypt_wq);
+err_destroy_handshake_send:
+	destroy_workqueue(wg->handshake_send_wq);
+err_destroy_handshake_receive:
+	destroy_workqueue(wg->handshake_receive_wq);
+err_free_index_hashtable:
+	kvfree(wg->index_hashtable);
+err_free_peer_hashtable:
+	kvfree(wg->peer_hashtable);
+	return ret;
+}
+
+static struct rtnl_link_ops link_ops __read_mostly = {
+	.kind			= KBUILD_MODNAME,
+	.priv_size		= sizeof(struct wg_device),
+	.setup			= wg_setup,
+	.newlink		= wg_newlink,
+};
+
+static void __net_exit wg_netns_exit_rtnl(struct net *net, struct list_head *dev_kill_list)
+{
+	struct wg_device *wg;
+	struct wg_peer *peer;
+
+	list_for_each_entry(wg, &device_list, device_list) {
+		if (rcu_access_pointer(wg->creating_net) == net) {
+			pr_debug("%s: Creating namespace exiting\n", wg->dev->name);
+			netif_carrier_off(wg->dev);
+			mutex_lock(&wg->device_update_lock);
+			rcu_assign_pointer(wg->creating_net, NULL);
+			wg_socket_reinit(wg, NULL, NULL);
+			list_for_each_entry(peer, &wg->peer_list, peer_list)
+				wg_socket_clear_peer_endpoint_src(peer);
+			mutex_unlock(&wg->device_update_lock);
+		}
+	}
+}
+
+static struct pernet_operations pernet_ops __read_mostly = {
+	.exit_rtnl = wg_netns_exit_rtnl
+};
+
+int __init wg_device_init(void)
+{
+	int ret;
+
+	ret = register_pm_notifier(&pm_notifier);
+	if (ret)
+		return ret;
+
+	ret = register_random_vmfork_notifier(&vm_notifier);
+	if (ret)
+		goto error_pm;
+
+	ret = register_pernet_device(&pernet_ops);
+	if (ret)
+		goto error_vm;
+
+	ret = rtnl_link_register(&link_ops);
+	if (ret)
+		goto error_pernet;
+
+	return 0;
+
+error_pernet:
+	unregister_pernet_device(&pernet_ops);
+error_vm:
+	unregister_random_vmfork_notifier(&vm_notifier);
+error_pm:
+	unregister_pm_notifier(&pm_notifier);
+	return ret;
+}
+
+void wg_device_uninit(void)
+{
+	rtnl_link_unregister(&link_ops);
+	unregister_pernet_device(&pernet_ops);
+	unregister_random_vmfork_notifier(&vm_notifier);
+	unregister_pm_notifier(&pm_notifier);
+	rcu_barrier();
+}

linux-7.2.3/drivers/net/wireguard/device.h

@@ -0,0 +1,62 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#ifndef _WG_DEVICE_H
+#define _WG_DEVICE_H
+
+#include "noise.h"
+#include "allowedips.h"
+#include "peerlookup.h"
+#include "cookie.h"
+
+#include <linux/types.h>
+#include <linux/netdevice.h>
+#include <linux/workqueue.h>
+#include <linux/mutex.h>
+#include <linux/net.h>
+#include <linux/ptr_ring.h>
+
+struct wg_device;
+
+struct multicore_worker {
+	void *ptr;
+	struct work_struct work;
+};
+
+struct crypt_queue {
+	struct ptr_ring ring;
+	struct multicore_worker __percpu *worker;
+	int last_cpu;
+};
+
+struct prev_queue {
+	struct sk_buff *head, *tail, *peeked;
+	struct { struct sk_buff *next, *prev; } empty; // Match first 2 members of struct sk_buff.
+	atomic_t count;
+};
+
+struct wg_device {
+	struct net_device *dev;
+	struct crypt_queue encrypt_queue, decrypt_queue, handshake_queue;
+	struct sock __rcu *sock4, *sock6;
+	struct net __rcu *creating_net;
+	struct noise_static_identity static_identity;
+	struct workqueue_struct *packet_crypt_wq,*handshake_receive_wq, *handshake_send_wq;
+	struct cookie_checker cookie_checker;
+	struct pubkey_hashtable *peer_hashtable;
+	struct index_hashtable *index_hashtable;
+	struct allowedips peer_allowedips;
+	struct mutex device_update_lock, socket_update_lock;
+	struct list_head device_list, peer_list;
+	atomic_t handshake_queue_len;
+	unsigned int num_peers, device_update_gen;
+	u32 fwmark;
+	u16 incoming_port;
+};
+
+int wg_device_init(void);
+void wg_device_uninit(void);
+
+#endif /* _WG_DEVICE_H */

linux-7.2.3/drivers/net/wireguard/generated/netlink.c

@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)
+/* Do not edit directly, auto-generated from: */
+/*	Documentation/netlink/specs/wireguard.yaml */
+/* YNL-GEN kernel source */
+/* YNL-ARG --function-prefix wg */
+/* To regenerate run: tools/net/ynl/ynl-regen.sh */
+
+#include <net/netlink.h>
+#include <net/genetlink.h>
+
+#include "netlink.h"
+
+#include <uapi/linux/wireguard.h>
+#include <linux/time_types.h>
+
+/* Common nested types */
+const struct nla_policy wireguard_wgallowedip_nl_policy[WGALLOWEDIP_A_FLAGS + 1] = {
+	[WGALLOWEDIP_A_FAMILY] = { .type = NLA_U16, },
+	[WGALLOWEDIP_A_IPADDR] = NLA_POLICY_MIN_LEN(4),
+	[WGALLOWEDIP_A_CIDR_MASK] = { .type = NLA_U8, },
+	[WGALLOWEDIP_A_FLAGS] = NLA_POLICY_MASK(NLA_U32, 0x1),
+};
+
+const struct nla_policy wireguard_wgpeer_nl_policy[WGPEER_A_PROTOCOL_VERSION + 1] = {
+	[WGPEER_A_PUBLIC_KEY] = NLA_POLICY_EXACT_LEN(WG_KEY_LEN),
+	[WGPEER_A_PRESHARED_KEY] = NLA_POLICY_EXACT_LEN(WG_KEY_LEN),
+	[WGPEER_A_FLAGS] = NLA_POLICY_MASK(NLA_U32, 0x7),
+	[WGPEER_A_ENDPOINT] = NLA_POLICY_MIN_LEN(16),
+	[WGPEER_A_PERSISTENT_KEEPALIVE_INTERVAL] = { .type = NLA_U16, },
+	[WGPEER_A_LAST_HANDSHAKE_TIME] = NLA_POLICY_EXACT_LEN(16),
+	[WGPEER_A_RX_BYTES] = { .type = NLA_U64, },
+	[WGPEER_A_TX_BYTES] = { .type = NLA_U64, },
+	[WGPEER_A_ALLOWEDIPS] = NLA_POLICY_NESTED_ARRAY(wireguard_wgallowedip_nl_policy),
+	[WGPEER_A_PROTOCOL_VERSION] = { .type = NLA_U32, },
+};
+
+/* WG_CMD_GET_DEVICE - dump */
+static const struct nla_policy wireguard_get_device_nl_policy[WGDEVICE_A_IFNAME + 1] = {
+	[WGDEVICE_A_IFINDEX] = { .type = NLA_U32, },
+	[WGDEVICE_A_IFNAME] = { .type = NLA_NUL_STRING, .len = 15, },
+};
+
+/* WG_CMD_SET_DEVICE - do */
+static const struct nla_policy wireguard_set_device_nl_policy[WGDEVICE_A_PEERS + 1] = {
+	[WGDEVICE_A_IFINDEX] = { .type = NLA_U32, },
+	[WGDEVICE_A_IFNAME] = { .type = NLA_NUL_STRING, .len = 15, },
+	[WGDEVICE_A_PRIVATE_KEY] = NLA_POLICY_EXACT_LEN(WG_KEY_LEN),
+	[WGDEVICE_A_PUBLIC_KEY] = NLA_POLICY_EXACT_LEN(WG_KEY_LEN),
+	[WGDEVICE_A_FLAGS] = NLA_POLICY_MASK(NLA_U32, 0x1),
+	[WGDEVICE_A_LISTEN_PORT] = { .type = NLA_U16, },
+	[WGDEVICE_A_FWMARK] = { .type = NLA_U32, },
+	[WGDEVICE_A_PEERS] = NLA_POLICY_NESTED_ARRAY(wireguard_wgpeer_nl_policy),
+};
+
+/* Ops table for wireguard */
+const struct genl_split_ops wireguard_nl_ops[2] = {
+	{
+		.cmd		= WG_CMD_GET_DEVICE,
+		.start		= wg_get_device_start,
+		.dumpit		= wg_get_device_dumpit,
+		.done		= wg_get_device_done,
+		.policy		= wireguard_get_device_nl_policy,
+		.maxattr	= WGDEVICE_A_IFNAME,
+		.flags		= GENL_UNS_ADMIN_PERM | GENL_CMD_CAP_DUMP,
+	},
+	{
+		.cmd		= WG_CMD_SET_DEVICE,
+		.doit		= wg_set_device_doit,
+		.policy		= wireguard_set_device_nl_policy,
+		.maxattr	= WGDEVICE_A_PEERS,
+		.flags		= GENL_UNS_ADMIN_PERM | GENL_CMD_CAP_DO,
+	},
+};

linux-7.2.3/drivers/net/wireguard/generated/netlink.h

@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) */
+/* Do not edit directly, auto-generated from: */
+/*	Documentation/netlink/specs/wireguard.yaml */
+/* YNL-GEN kernel header */
+/* YNL-ARG --function-prefix wg */
+/* To regenerate run: tools/net/ynl/ynl-regen.sh */
+
+#ifndef _LINUX_WIREGUARD_GEN_H
+#define _LINUX_WIREGUARD_GEN_H
+
+#include <net/netlink.h>
+#include <net/genetlink.h>
+
+#include <uapi/linux/wireguard.h>
+#include <linux/time_types.h>
+
+/* Common nested types */
+extern const struct nla_policy wireguard_wgallowedip_nl_policy[WGALLOWEDIP_A_FLAGS + 1];
+extern const struct nla_policy wireguard_wgpeer_nl_policy[WGPEER_A_PROTOCOL_VERSION + 1];
+
+/* Ops table for wireguard */
+extern const struct genl_split_ops wireguard_nl_ops[2];
+
+int wg_get_device_start(struct netlink_callback *cb);
+int wg_get_device_done(struct netlink_callback *cb);
+
+int wg_get_device_dumpit(struct sk_buff *skb, struct netlink_callback *cb);
+int wg_set_device_doit(struct sk_buff *skb, struct genl_info *info);
+
+#endif /* _LINUX_WIREGUARD_GEN_H */

linux-7.2.3/drivers/net/wireguard/main.c

@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include "version.h"
+#include "device.h"
+#include "noise.h"
+#include "queueing.h"
+#include "ratelimiter.h"
+#include "netlink.h"
+
+#include <uapi/linux/wireguard.h>
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <net/genetlink.h>
+#include <net/rtnetlink.h>
+
+static int __init wg_mod_init(void)
+{
+	int ret;
+
+	ret = wg_allowedips_slab_init();
+	if (ret < 0)
+		goto err_allowedips;
+
+#ifdef DEBUG
+	ret = -ENOTRECOVERABLE;
+	if (!wg_allowedips_selftest() || !wg_packet_counter_selftest() ||
+	    !wg_ratelimiter_selftest())
+		goto err_peer;
+#endif
+	wg_noise_init();
+
+	ret = wg_peer_init();
+	if (ret < 0)
+		goto err_peer;
+
+	ret = wg_device_init();
+	if (ret < 0)
+		goto err_device;
+
+	ret = wg_genetlink_init();
+	if (ret < 0)
+		goto err_netlink;
+
+	pr_info("WireGuard " WIREGUARD_VERSION " loaded. See www.wireguard.com for information.\n");
+	pr_info("Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.\n");
+
+	return 0;
+
+err_netlink:
+	wg_device_uninit();
+err_device:
+	wg_peer_uninit();
+err_peer:
+	wg_allowedips_slab_uninit();
+err_allowedips:
+	return ret;
+}
+
+static void __exit wg_mod_exit(void)
+{
+	wg_genetlink_uninit();
+	wg_device_uninit();
+	wg_peer_uninit();
+	wg_allowedips_slab_uninit();
+}
+
+module_init(wg_mod_init);
+module_exit(wg_mod_exit);
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("WireGuard secure network tunnel");
+MODULE_AUTHOR("Jason A. Donenfeld <Jason@zx2c4.com>");
+MODULE_VERSION(WIREGUARD_VERSION);
+MODULE_ALIAS_RTNL_LINK(KBUILD_MODNAME);
+MODULE_ALIAS_GENL_FAMILY(WG_GENL_NAME);

linux-7.2.3/drivers/net/wireguard/messages.h

@@ -0,0 +1,128 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#ifndef _WG_MESSAGES_H
+#define _WG_MESSAGES_H
+
+#include <crypto/curve25519.h>
+#include <crypto/chacha20poly1305.h>
+#include <crypto/blake2s.h>
+
+#include <linux/kernel.h>
+#include <linux/param.h>
+#include <linux/skbuff.h>
+
+enum noise_lengths {
+	NOISE_PUBLIC_KEY_LEN = CURVE25519_KEY_SIZE,
+	NOISE_SYMMETRIC_KEY_LEN = CHACHA20POLY1305_KEY_SIZE,
+	NOISE_TIMESTAMP_LEN = sizeof(u64) + sizeof(u32),
+	NOISE_AUTHTAG_LEN = CHACHA20POLY1305_AUTHTAG_SIZE,
+	NOISE_HASH_LEN = BLAKE2S_HASH_SIZE
+};
+
+#define noise_encrypted_len(plain_len) ((plain_len) + NOISE_AUTHTAG_LEN)
+
+enum cookie_values {
+	COOKIE_SECRET_MAX_AGE = 2 * 60,
+	COOKIE_SECRET_LATENCY = 5,
+	COOKIE_NONCE_LEN = XCHACHA20POLY1305_NONCE_SIZE,
+	COOKIE_LEN = 16
+};
+
+enum counter_values {
+	COUNTER_BITS_TOTAL = 8192,
+	COUNTER_REDUNDANT_BITS = BITS_PER_LONG,
+	COUNTER_WINDOW_SIZE = COUNTER_BITS_TOTAL - COUNTER_REDUNDANT_BITS
+};
+
+enum limits {
+	REKEY_AFTER_MESSAGES = 1ULL << 60,
+	REJECT_AFTER_MESSAGES = U64_MAX - COUNTER_WINDOW_SIZE - 1,
+	REKEY_TIMEOUT = 5,
+	REKEY_TIMEOUT_JITTER_MAX_JIFFIES = HZ / 3,
+	REKEY_AFTER_TIME = 120,
+	REJECT_AFTER_TIME = 180,
+	INITIATIONS_PER_SECOND = 50,
+	MAX_PEERS_PER_DEVICE = 1U << 20,
+	KEEPALIVE_TIMEOUT = 10,
+	MAX_TIMER_HANDSHAKES = 90 / REKEY_TIMEOUT,
+	MAX_QUEUED_INCOMING_HANDSHAKES = 4096, /* TODO: replace this with DQL */
+	MAX_STAGED_PACKETS = 128,
+	MAX_QUEUED_PACKETS = 1024 /* TODO: replace this with DQL */
+};
+
+enum message_type {
+	MESSAGE_INVALID = 0,
+	MESSAGE_HANDSHAKE_INITIATION = 1,
+	MESSAGE_HANDSHAKE_RESPONSE = 2,
+	MESSAGE_HANDSHAKE_COOKIE = 3,
+	MESSAGE_DATA = 4
+};
+
+struct message_header {
+	/* The actual layout of this that we want is:
+	 * u8 type
+	 * u8 reserved_zero[3]
+	 *
+	 * But it turns out that by encoding this as little endian,
+	 * we achieve the same thing, and it makes checking faster.
+	 */
+	__le32 type;
+};
+
+struct message_macs {
+	u8 mac1[COOKIE_LEN];
+	u8 mac2[COOKIE_LEN];
+};
+
+struct message_handshake_initiation {
+	struct message_header header;
+	__le32 sender_index;
+	u8 unencrypted_ephemeral[NOISE_PUBLIC_KEY_LEN];
+	u8 encrypted_static[noise_encrypted_len(NOISE_PUBLIC_KEY_LEN)];
+	u8 encrypted_timestamp[noise_encrypted_len(NOISE_TIMESTAMP_LEN)];
+	struct message_macs macs;
+};
+
+struct message_handshake_response {
+	struct message_header header;
+	__le32 sender_index;
+	__le32 receiver_index;
+	u8 unencrypted_ephemeral[NOISE_PUBLIC_KEY_LEN];
+	u8 encrypted_nothing[noise_encrypted_len(0)];
+	struct message_macs macs;
+};
+
+struct message_handshake_cookie {
+	struct message_header header;
+	__le32 receiver_index;
+	u8 nonce[COOKIE_NONCE_LEN];
+	u8 encrypted_cookie[noise_encrypted_len(COOKIE_LEN)];
+};
+
+struct message_data {
+	struct message_header header;
+	__le32 key_idx;
+	__le64 counter;
+	u8 encrypted_data[];
+};
+
+#define message_data_len(plain_len) \
+	(noise_encrypted_len(plain_len) + sizeof(struct message_data))
+
+enum message_alignments {
+	MESSAGE_PADDING_MULTIPLE = 16,
+	MESSAGE_MINIMUM_LENGTH = message_data_len(0)
+};
+
+#define SKB_HEADER_LEN                                       \
+	(max(sizeof(struct iphdr), sizeof(struct ipv6hdr)) + \
+	 sizeof(struct udphdr) + NET_SKB_PAD)
+#define DATA_PACKET_HEAD_ROOM \
+	ALIGN(sizeof(struct message_data) + SKB_HEADER_LEN, 4)
+
+enum { HANDSHAKE_DSCP = 0x88 /* AF41, plus 00 ECN */ };
+
+#endif /* _WG_MESSAGES_H */

linux-7.2.3/drivers/net/wireguard/netlink.c

@@ -0,0 +1,607 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include "netlink.h"
+#include "device.h"
+#include "peer.h"
+#include "socket.h"
+#include "queueing.h"
+#include "messages.h"
+#include "generated/netlink.h"
+
+#include <uapi/linux/wireguard.h>
+
+#include <linux/if.h>
+#include <net/genetlink.h>
+#include <net/sock.h>
+#include <crypto/utils.h>
+
+static struct genl_family genl_family;
+
+static struct wg_device *lookup_interface(struct nlattr **attrs,
+					  struct sk_buff *skb)
+{
+	struct net_device *dev = NULL;
+
+	if (!attrs[WGDEVICE_A_IFINDEX] == !attrs[WGDEVICE_A_IFNAME])
+		return ERR_PTR(-EBADR);
+	if (attrs[WGDEVICE_A_IFINDEX])
+		dev = dev_get_by_index(sock_net(skb->sk),
+				       nla_get_u32(attrs[WGDEVICE_A_IFINDEX]));
+	else if (attrs[WGDEVICE_A_IFNAME])
+		dev = dev_get_by_name(sock_net(skb->sk),
+				      nla_data(attrs[WGDEVICE_A_IFNAME]));
+	if (!dev)
+		return ERR_PTR(-ENODEV);
+	if (!dev->rtnl_link_ops || !dev->rtnl_link_ops->kind ||
+	    strcmp(dev->rtnl_link_ops->kind, KBUILD_MODNAME)) {
+		dev_put(dev);
+		return ERR_PTR(-EOPNOTSUPP);
+	}
+	return netdev_priv(dev);
+}
+
+static int get_allowedips(struct sk_buff *skb, const u8 *ip, u8 cidr,
+			  int family)
+{
+	struct nlattr *allowedip_nest;
+
+	allowedip_nest = nla_nest_start(skb, 0);
+	if (!allowedip_nest)
+		return -EMSGSIZE;
+
+	if (nla_put_u8(skb, WGALLOWEDIP_A_CIDR_MASK, cidr) ||
+	    nla_put_u16(skb, WGALLOWEDIP_A_FAMILY, family) ||
+	    nla_put(skb, WGALLOWEDIP_A_IPADDR, family == AF_INET6 ?
+		    sizeof(struct in6_addr) : sizeof(struct in_addr), ip)) {
+		nla_nest_cancel(skb, allowedip_nest);
+		return -EMSGSIZE;
+	}
+
+	nla_nest_end(skb, allowedip_nest);
+	return 0;
+}
+
+struct dump_ctx {
+	struct wg_device *wg;
+	struct wg_peer *next_peer;
+	u64 allowedips_seq;
+	struct allowedips_node *next_allowedip;
+};
+
+#define DUMP_CTX(cb) ((struct dump_ctx *)(cb)->args)
+
+static int
+get_peer(struct wg_peer *peer, struct sk_buff *skb, struct dump_ctx *ctx)
+{
+
+	struct nlattr *allowedips_nest, *peer_nest = nla_nest_start(skb, 0);
+	struct allowedips_node *allowedips_node = ctx->next_allowedip;
+	bool fail;
+
+	if (!peer_nest)
+		return -EMSGSIZE;
+
+	down_read(&peer->handshake.lock);
+	fail = nla_put(skb, WGPEER_A_PUBLIC_KEY, NOISE_PUBLIC_KEY_LEN,
+		       peer->handshake.remote_static);
+	up_read(&peer->handshake.lock);
+	if (fail)
+		goto err;
+
+	if (!allowedips_node) {
+		const struct __kernel_timespec last_handshake = {
+			.tv_sec = peer->walltime_last_handshake.tv_sec,
+			.tv_nsec = peer->walltime_last_handshake.tv_nsec
+		};
+
+		down_read(&peer->handshake.lock);
+		fail = nla_put(skb, WGPEER_A_PRESHARED_KEY,
+			       NOISE_SYMMETRIC_KEY_LEN,
+			       peer->handshake.preshared_key);
+		up_read(&peer->handshake.lock);
+		if (fail)
+			goto err;
+
+		if (nla_put(skb, WGPEER_A_LAST_HANDSHAKE_TIME,
+			    sizeof(last_handshake), &last_handshake) ||
+		    nla_put_u16(skb, WGPEER_A_PERSISTENT_KEEPALIVE_INTERVAL,
+				peer->persistent_keepalive_interval) ||
+		    nla_put_u64_64bit(skb, WGPEER_A_TX_BYTES, peer->tx_bytes,
+				      WGPEER_A_UNSPEC) ||
+		    nla_put_u64_64bit(skb, WGPEER_A_RX_BYTES, peer->rx_bytes,
+				      WGPEER_A_UNSPEC) ||
+		    nla_put_u32(skb, WGPEER_A_PROTOCOL_VERSION, 1))
+			goto err;
+
+		read_lock_bh(&peer->endpoint_lock);
+		if (peer->endpoint.addr.sa_family == AF_INET)
+			fail = nla_put(skb, WGPEER_A_ENDPOINT,
+				       sizeof(peer->endpoint.addr4),
+				       &peer->endpoint.addr4);
+		else if (peer->endpoint.addr.sa_family == AF_INET6)
+			fail = nla_put(skb, WGPEER_A_ENDPOINT,
+				       sizeof(peer->endpoint.addr6),
+				       &peer->endpoint.addr6);
+		read_unlock_bh(&peer->endpoint_lock);
+		if (fail)
+			goto err;
+		allowedips_node =
+			list_first_entry_or_null(&peer->allowedips_list,
+					struct allowedips_node, peer_list);
+	}
+	if (!allowedips_node)
+		goto no_allowedips;
+	if (!ctx->allowedips_seq)
+		ctx->allowedips_seq = ctx->wg->peer_allowedips.seq;
+	else if (ctx->allowedips_seq != ctx->wg->peer_allowedips.seq)
+		goto no_allowedips;
+
+	allowedips_nest = nla_nest_start(skb, WGPEER_A_ALLOWEDIPS);
+	if (!allowedips_nest)
+		goto err;
+
+	list_for_each_entry_from(allowedips_node, &peer->allowedips_list,
+				 peer_list) {
+		u8 cidr, ip[16] __aligned(__alignof(u64));
+		int family;
+
+		family = wg_allowedips_read_node(allowedips_node, ip, &cidr);
+		if (get_allowedips(skb, ip, cidr, family)) {
+			nla_nest_end(skb, allowedips_nest);
+			nla_nest_end(skb, peer_nest);
+			ctx->next_allowedip = allowedips_node;
+			return -EMSGSIZE;
+		}
+	}
+	nla_nest_end(skb, allowedips_nest);
+no_allowedips:
+	nla_nest_end(skb, peer_nest);
+	ctx->next_allowedip = NULL;
+	ctx->allowedips_seq = 0;
+	return 0;
+err:
+	nla_nest_cancel(skb, peer_nest);
+	return -EMSGSIZE;
+}
+
+int wg_get_device_start(struct netlink_callback *cb)
+{
+	struct wg_device *wg;
+
+	wg = lookup_interface(genl_info_dump(cb)->attrs, cb->skb);
+	if (IS_ERR(wg))
+		return PTR_ERR(wg);
+	DUMP_CTX(cb)->wg = wg;
+	return 0;
+}
+
+int wg_get_device_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	struct wg_peer *peer, *next_peer_cursor;
+	struct dump_ctx *ctx = DUMP_CTX(cb);
+	struct wg_device *wg = ctx->wg;
+	struct nlattr *peers_nest;
+	int ret = -EMSGSIZE;
+	bool done = true;
+	void *hdr;
+
+	rtnl_lock();
+	mutex_lock(&wg->device_update_lock);
+	cb->seq = wg->device_update_gen;
+	next_peer_cursor = ctx->next_peer;
+
+	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
+			  &genl_family, NLM_F_MULTI, WG_CMD_GET_DEVICE);
+	if (!hdr)
+		goto out;
+	genl_dump_check_consistent(cb, hdr);
+
+	if (!ctx->next_peer) {
+		if (nla_put_u16(skb, WGDEVICE_A_LISTEN_PORT,
+				wg->incoming_port) ||
+		    nla_put_u32(skb, WGDEVICE_A_FWMARK, wg->fwmark) ||
+		    nla_put_u32(skb, WGDEVICE_A_IFINDEX, wg->dev->ifindex) ||
+		    nla_put_string(skb, WGDEVICE_A_IFNAME, wg->dev->name))
+			goto out;
+
+		down_read(&wg->static_identity.lock);
+		if (wg->static_identity.has_identity) {
+			if (nla_put(skb, WGDEVICE_A_PRIVATE_KEY,
+				    NOISE_PUBLIC_KEY_LEN,
+				    wg->static_identity.static_private) ||
+			    nla_put(skb, WGDEVICE_A_PUBLIC_KEY,
+				    NOISE_PUBLIC_KEY_LEN,
+				    wg->static_identity.static_public)) {
+				up_read(&wg->static_identity.lock);
+				goto out;
+			}
+		}
+		up_read(&wg->static_identity.lock);
+	}
+
+	peers_nest = nla_nest_start(skb, WGDEVICE_A_PEERS);
+	if (!peers_nest)
+		goto out;
+	ret = 0;
+	lockdep_assert_held(&wg->device_update_lock);
+	/* If the last cursor was removed in peer_remove or peer_remove_all, then
+	 * we just treat this the same as there being no more peers left. The
+	 * reason is that seq_nr should indicate to userspace that this isn't a
+	 * coherent dump anyway, so they'll try again.
+	 */
+	if (list_empty(&wg->peer_list) ||
+	    (ctx->next_peer && ctx->next_peer->is_dead)) {
+		nla_nest_cancel(skb, peers_nest);
+		goto out;
+	}
+	peer = list_prepare_entry(ctx->next_peer, &wg->peer_list, peer_list);
+	list_for_each_entry_continue(peer, &wg->peer_list, peer_list) {
+		if (get_peer(peer, skb, ctx)) {
+			done = false;
+			break;
+		}
+		next_peer_cursor = peer;
+	}
+	nla_nest_end(skb, peers_nest);
+
+out:
+	if (!ret && !done && next_peer_cursor)
+		wg_peer_get(next_peer_cursor);
+	wg_peer_put(ctx->next_peer);
+	mutex_unlock(&wg->device_update_lock);
+	rtnl_unlock();
+
+	if (ret) {
+		genlmsg_cancel(skb, hdr);
+		return ret;
+	}
+	genlmsg_end(skb, hdr);
+	if (done) {
+		ctx->next_peer = NULL;
+		return 0;
+	}
+	ctx->next_peer = next_peer_cursor;
+	return skb->len;
+
+	/* At this point, we can't really deal ourselves with safely zeroing out
+	 * the private key material after usage. This will need an additional API
+	 * in the kernel for marking skbs as zero_on_free.
+	 */
+}
+
+int wg_get_device_done(struct netlink_callback *cb)
+{
+	struct dump_ctx *ctx = DUMP_CTX(cb);
+
+	if (ctx->wg)
+		dev_put(ctx->wg->dev);
+	wg_peer_put(ctx->next_peer);
+	return 0;
+}
+
+static int set_port(struct wg_device *wg, u16 port)
+{
+	struct wg_peer *peer;
+
+	if (wg->incoming_port == port)
+		return 0;
+	list_for_each_entry(peer, &wg->peer_list, peer_list)
+		wg_socket_clear_peer_endpoint_src(peer);
+	if (!netif_running(wg->dev)) {
+		wg->incoming_port = port;
+		return 0;
+	}
+	return wg_socket_init(wg, port);
+}
+
+static int set_allowedip(struct wg_peer *peer, struct nlattr **attrs)
+{
+	int ret = -EINVAL;
+	u32 flags = 0;
+	u16 family;
+	u8 cidr;
+
+	if (!attrs[WGALLOWEDIP_A_FAMILY] || !attrs[WGALLOWEDIP_A_IPADDR] ||
+	    !attrs[WGALLOWEDIP_A_CIDR_MASK])
+		return ret;
+	family = nla_get_u16(attrs[WGALLOWEDIP_A_FAMILY]);
+	cidr = nla_get_u8(attrs[WGALLOWEDIP_A_CIDR_MASK]);
+	if (attrs[WGALLOWEDIP_A_FLAGS])
+		flags = nla_get_u32(attrs[WGALLOWEDIP_A_FLAGS]);
+
+	if (family == AF_INET && cidr <= 32 &&
+	    nla_len(attrs[WGALLOWEDIP_A_IPADDR]) == sizeof(struct in_addr)) {
+		if (flags & WGALLOWEDIP_F_REMOVE_ME)
+			ret = wg_allowedips_remove_v4(&peer->device->peer_allowedips,
+						      nla_data(attrs[WGALLOWEDIP_A_IPADDR]), cidr,
+						      peer, &peer->device->device_update_lock);
+		else
+			ret = wg_allowedips_insert_v4(&peer->device->peer_allowedips,
+						      nla_data(attrs[WGALLOWEDIP_A_IPADDR]), cidr,
+						      peer, &peer->device->device_update_lock);
+	} else if (family == AF_INET6 && cidr <= 128 &&
+		   nla_len(attrs[WGALLOWEDIP_A_IPADDR]) == sizeof(struct in6_addr)) {
+		if (flags & WGALLOWEDIP_F_REMOVE_ME)
+			ret = wg_allowedips_remove_v6(&peer->device->peer_allowedips,
+						      nla_data(attrs[WGALLOWEDIP_A_IPADDR]), cidr,
+						      peer, &peer->device->device_update_lock);
+		else
+			ret = wg_allowedips_insert_v6(&peer->device->peer_allowedips,
+						      nla_data(attrs[WGALLOWEDIP_A_IPADDR]), cidr,
+						      peer, &peer->device->device_update_lock);
+	}
+
+	return ret;
+}
+
+static int set_peer(struct wg_device *wg, struct nlattr **attrs)
+{
+	u8 *public_key = NULL, *preshared_key = NULL;
+	struct wg_peer *peer = NULL;
+	u32 flags = 0;
+	int ret;
+
+	ret = -EINVAL;
+	if (attrs[WGPEER_A_PUBLIC_KEY] &&
+	    nla_len(attrs[WGPEER_A_PUBLIC_KEY]) == NOISE_PUBLIC_KEY_LEN)
+		public_key = nla_data(attrs[WGPEER_A_PUBLIC_KEY]);
+	else
+		goto out;
+	if (attrs[WGPEER_A_PRESHARED_KEY] &&
+	    nla_len(attrs[WGPEER_A_PRESHARED_KEY]) == NOISE_SYMMETRIC_KEY_LEN)
+		preshared_key = nla_data(attrs[WGPEER_A_PRESHARED_KEY]);
+
+	if (attrs[WGPEER_A_FLAGS])
+		flags = nla_get_u32(attrs[WGPEER_A_FLAGS]);
+
+	ret = -EPFNOSUPPORT;
+	if (attrs[WGPEER_A_PROTOCOL_VERSION]) {
+		if (nla_get_u32(attrs[WGPEER_A_PROTOCOL_VERSION]) != 1)
+			goto out;
+	}
+
+	peer = wg_pubkey_hashtable_lookup(wg->peer_hashtable,
+					  nla_data(attrs[WGPEER_A_PUBLIC_KEY]));
+	ret = 0;
+	if (!peer) { /* Peer doesn't exist yet. Add a new one. */
+		if (flags & (WGPEER_F_REMOVE_ME | WGPEER_F_UPDATE_ONLY))
+			goto out;
+
+		/* The peer is new, so there aren't allowed IPs to remove. */
+		flags &= ~WGPEER_F_REPLACE_ALLOWEDIPS;
+
+		down_read(&wg->static_identity.lock);
+		if (wg->static_identity.has_identity &&
+		    !memcmp(nla_data(attrs[WGPEER_A_PUBLIC_KEY]),
+			    wg->static_identity.static_public,
+			    NOISE_PUBLIC_KEY_LEN)) {
+			/* We silently ignore peers that have the same public
+			 * key as the device. The reason we do it silently is
+			 * that we'd like for people to be able to reuse the
+			 * same set of API calls across peers.
+			 */
+			up_read(&wg->static_identity.lock);
+			ret = 0;
+			goto out;
+		}
+		up_read(&wg->static_identity.lock);
+
+		peer = wg_peer_create(wg, public_key, preshared_key);
+		if (IS_ERR(peer)) {
+			ret = PTR_ERR(peer);
+			peer = NULL;
+			goto out;
+		}
+		/* Take additional reference, as though we've just been
+		 * looked up.
+		 */
+		wg_peer_get(peer);
+	}
+
+	if (flags & WGPEER_F_REMOVE_ME) {
+		wg_peer_remove(peer);
+		goto out;
+	}
+
+	if (preshared_key) {
+		down_write(&peer->handshake.lock);
+		memcpy(&peer->handshake.preshared_key, preshared_key,
+		       NOISE_SYMMETRIC_KEY_LEN);
+		up_write(&peer->handshake.lock);
+	}
+
+	if (attrs[WGPEER_A_ENDPOINT]) {
+		struct sockaddr *addr = nla_data(attrs[WGPEER_A_ENDPOINT]);
+		size_t len = nla_len(attrs[WGPEER_A_ENDPOINT]);
+		struct endpoint endpoint = { { { 0 } } };
+
+		if (len == sizeof(struct sockaddr_in) && addr->sa_family == AF_INET) {
+			endpoint.addr4 = *(struct sockaddr_in *)addr;
+			wg_socket_set_peer_endpoint(peer, &endpoint);
+		} else if (len == sizeof(struct sockaddr_in6) && addr->sa_family == AF_INET6) {
+			endpoint.addr6 = *(struct sockaddr_in6 *)addr;
+			wg_socket_set_peer_endpoint(peer, &endpoint);
+		}
+	}
+
+	if (flags & WGPEER_F_REPLACE_ALLOWEDIPS)
+		wg_allowedips_remove_by_peer(&wg->peer_allowedips, peer,
+					     &wg->device_update_lock);
+
+	if (attrs[WGPEER_A_ALLOWEDIPS]) {
+		struct nlattr *attr, *allowedip[WGALLOWEDIP_A_MAX + 1];
+		int rem;
+
+		nla_for_each_nested(attr, attrs[WGPEER_A_ALLOWEDIPS], rem) {
+			ret = nla_parse_nested(allowedip, WGALLOWEDIP_A_MAX,
+					       attr, NULL, NULL);
+			if (ret < 0)
+				goto out;
+			ret = set_allowedip(peer, allowedip);
+			if (ret < 0)
+				goto out;
+		}
+	}
+
+	if (attrs[WGPEER_A_PERSISTENT_KEEPALIVE_INTERVAL]) {
+		const u16 persistent_keepalive_interval = nla_get_u16(
+				attrs[WGPEER_A_PERSISTENT_KEEPALIVE_INTERVAL]);
+		const bool send_keepalive =
+			!peer->persistent_keepalive_interval &&
+			persistent_keepalive_interval &&
+			netif_running(wg->dev);
+
+		peer->persistent_keepalive_interval = persistent_keepalive_interval;
+		if (send_keepalive)
+			wg_packet_send_keepalive(peer);
+	}
+
+	if (netif_running(wg->dev))
+		wg_packet_send_staged_packets(peer);
+
+out:
+	wg_peer_put(peer);
+	if (attrs[WGPEER_A_PRESHARED_KEY])
+		memzero_explicit(nla_data(attrs[WGPEER_A_PRESHARED_KEY]),
+				 nla_len(attrs[WGPEER_A_PRESHARED_KEY]));
+	return ret;
+}
+
+int wg_set_device_doit(struct sk_buff *skb, struct genl_info *info)
+{
+	struct wg_device *wg = lookup_interface(info->attrs, skb);
+	u32 flags = 0;
+	int ret;
+
+	if (IS_ERR(wg)) {
+		ret = PTR_ERR(wg);
+		goto out_nodev;
+	}
+
+	rtnl_lock();
+	mutex_lock(&wg->device_update_lock);
+
+	if (info->attrs[WGDEVICE_A_FLAGS])
+		flags = nla_get_u32(info->attrs[WGDEVICE_A_FLAGS]);
+
+	if (info->attrs[WGDEVICE_A_LISTEN_PORT] || info->attrs[WGDEVICE_A_FWMARK]) {
+		struct net *net;
+		rcu_read_lock();
+		net = rcu_dereference(wg->creating_net);
+		ret = !net || !ns_capable(net->user_ns, CAP_NET_ADMIN) ? -EPERM : 0;
+		rcu_read_unlock();
+		if (ret)
+			goto out;
+	}
+
+	++wg->device_update_gen;
+
+	if (info->attrs[WGDEVICE_A_FWMARK]) {
+		struct wg_peer *peer;
+
+		wg->fwmark = nla_get_u32(info->attrs[WGDEVICE_A_FWMARK]);
+		list_for_each_entry(peer, &wg->peer_list, peer_list)
+			wg_socket_clear_peer_endpoint_src(peer);
+	}
+
+	if (info->attrs[WGDEVICE_A_LISTEN_PORT]) {
+		ret = set_port(wg,
+			nla_get_u16(info->attrs[WGDEVICE_A_LISTEN_PORT]));
+		if (ret)
+			goto out;
+	}
+
+	if (flags & WGDEVICE_F_REPLACE_PEERS)
+		wg_peer_remove_all(wg);
+
+	if (info->attrs[WGDEVICE_A_PRIVATE_KEY] &&
+	    nla_len(info->attrs[WGDEVICE_A_PRIVATE_KEY]) ==
+		    NOISE_PUBLIC_KEY_LEN) {
+		u8 *private_key = nla_data(info->attrs[WGDEVICE_A_PRIVATE_KEY]);
+		u8 public_key[NOISE_PUBLIC_KEY_LEN];
+		struct wg_peer *peer, *temp;
+		bool send_staged_packets;
+
+		if (!crypto_memneq(wg->static_identity.static_private,
+				   private_key, NOISE_PUBLIC_KEY_LEN))
+			goto skip_set_private_key;
+
+		/* We remove before setting, to prevent race, which means doing
+		 * two 25519-genpub ops.
+		 */
+		if (curve25519_generate_public(public_key, private_key)) {
+			peer = wg_pubkey_hashtable_lookup(wg->peer_hashtable,
+							  public_key);
+			if (peer) {
+				wg_peer_put(peer);
+				wg_peer_remove(peer);
+			}
+		}
+
+		down_write(&wg->static_identity.lock);
+		send_staged_packets = !wg->static_identity.has_identity && netif_running(wg->dev);
+		wg_noise_set_static_identity_private_key(&wg->static_identity, private_key);
+		send_staged_packets = send_staged_packets && wg->static_identity.has_identity;
+
+		wg_cookie_checker_precompute_device_keys(&wg->cookie_checker);
+		list_for_each_entry_safe(peer, temp, &wg->peer_list, peer_list) {
+			wg_noise_precompute_static_static(peer);
+			wg_noise_expire_current_peer_keypairs(peer);
+			if (send_staged_packets)
+				wg_packet_send_staged_packets(peer);
+		}
+		up_write(&wg->static_identity.lock);
+	}
+skip_set_private_key:
+
+	if (info->attrs[WGDEVICE_A_PEERS]) {
+		struct nlattr *attr, *peer[WGPEER_A_MAX + 1];
+		int rem;
+
+		nla_for_each_nested(attr, info->attrs[WGDEVICE_A_PEERS], rem) {
+			ret = nla_parse_nested(peer, WGPEER_A_MAX, attr,
+					       NULL, NULL);
+			if (ret < 0)
+				goto out;
+			ret = set_peer(wg, peer);
+			if (ret < 0)
+				goto out;
+		}
+	}
+	ret = 0;
+
+out:
+	mutex_unlock(&wg->device_update_lock);
+	rtnl_unlock();
+	dev_put(wg->dev);
+out_nodev:
+	if (info->attrs[WGDEVICE_A_PRIVATE_KEY])
+		memzero_explicit(nla_data(info->attrs[WGDEVICE_A_PRIVATE_KEY]),
+				 nla_len(info->attrs[WGDEVICE_A_PRIVATE_KEY]));
+	return ret;
+}
+
+static struct genl_family genl_family __ro_after_init = {
+	.split_ops = wireguard_nl_ops,
+	.n_split_ops = ARRAY_SIZE(wireguard_nl_ops),
+	.name = WG_GENL_NAME,
+	.version = WG_GENL_VERSION,
+	.module = THIS_MODULE,
+	.netnsok = true
+};
+
+int __init wg_genetlink_init(void)
+{
+	BUILD_BUG_ON(WG_KEY_LEN != NOISE_PUBLIC_KEY_LEN);
+	BUILD_BUG_ON(WG_KEY_LEN != NOISE_SYMMETRIC_KEY_LEN);
+
+	return genl_register_family(&genl_family);
+}
+
+void __exit wg_genetlink_uninit(void)
+{
+	genl_unregister_family(&genl_family);
+}

linux-7.2.3/drivers/net/wireguard/netlink.h

@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#ifndef _WG_NETLINK_H
+#define _WG_NETLINK_H
+
+int wg_genetlink_init(void);
+void wg_genetlink_uninit(void);
+
+#endif /* _WG_NETLINK_H */

linux-7.2.3/drivers/net/wireguard/noise.c

@@ -0,0 +1,861 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include "noise.h"
+#include "device.h"
+#include "peer.h"
+#include "messages.h"
+#include "queueing.h"
+#include "peerlookup.h"
+
+#include <linux/rcupdate.h>
+#include <linux/slab.h>
+#include <linux/bitmap.h>
+#include <linux/scatterlist.h>
+#include <linux/highmem.h>
+#include <crypto/utils.h>
+
+/* This implements Noise_IKpsk2:
+ *
+ * <- s
+ * ******
+ * -> e, es, s, ss, {t}
+ * <- e, ee, se, psk, {}
+ */
+
+static const u8 handshake_name[37] __nonstring = "Noise_IKpsk2_25519_ChaChaPoly_BLAKE2s";
+static const u8 identifier_name[34] __nonstring = "WireGuard v1 zx2c4 Jason@zx2c4.com";
+static u8 handshake_init_hash[NOISE_HASH_LEN] __ro_after_init;
+static u8 handshake_init_chaining_key[NOISE_HASH_LEN] __ro_after_init;
+static atomic64_t keypair_counter = ATOMIC64_INIT(0);
+
+void __init wg_noise_init(void)
+{
+	struct blake2s_ctx blake;
+
+	blake2s(NULL, 0, handshake_name, sizeof(handshake_name),
+		handshake_init_chaining_key, NOISE_HASH_LEN);
+	blake2s_init(&blake, NOISE_HASH_LEN);
+	blake2s_update(&blake, handshake_init_chaining_key, NOISE_HASH_LEN);
+	blake2s_update(&blake, identifier_name, sizeof(identifier_name));
+	blake2s_final(&blake, handshake_init_hash);
+}
+
+/* Must hold peer->handshake.static_identity->lock */
+void wg_noise_precompute_static_static(struct wg_peer *peer)
+{
+	down_write(&peer->handshake.lock);
+	if (!peer->handshake.static_identity->has_identity ||
+	    !curve25519(peer->handshake.precomputed_static_static,
+			peer->handshake.static_identity->static_private,
+			peer->handshake.remote_static))
+		memset(peer->handshake.precomputed_static_static, 0,
+		       NOISE_PUBLIC_KEY_LEN);
+	up_write(&peer->handshake.lock);
+}
+
+void wg_noise_handshake_init(struct noise_handshake *handshake,
+			     struct noise_static_identity *static_identity,
+			     const u8 peer_public_key[NOISE_PUBLIC_KEY_LEN],
+			     const u8 peer_preshared_key[NOISE_SYMMETRIC_KEY_LEN],
+			     struct wg_peer *peer)
+{
+	memset(handshake, 0, sizeof(*handshake));
+	init_rwsem(&handshake->lock);
+	handshake->entry.type = INDEX_HASHTABLE_HANDSHAKE;
+	handshake->entry.peer = peer;
+	memcpy(handshake->remote_static, peer_public_key, NOISE_PUBLIC_KEY_LEN);
+	if (peer_preshared_key)
+		memcpy(handshake->preshared_key, peer_preshared_key,
+		       NOISE_SYMMETRIC_KEY_LEN);
+	handshake->static_identity = static_identity;
+	handshake->state = HANDSHAKE_ZEROED;
+	wg_noise_precompute_static_static(peer);
+}
+
+static void handshake_zero(struct noise_handshake *handshake)
+{
+	memset(&handshake->ephemeral_private, 0, NOISE_PUBLIC_KEY_LEN);
+	memset(&handshake->remote_ephemeral, 0, NOISE_PUBLIC_KEY_LEN);
+	memset(&handshake->hash, 0, NOISE_HASH_LEN);
+	memset(&handshake->chaining_key, 0, NOISE_HASH_LEN);
+	handshake->remote_index = 0;
+	handshake->state = HANDSHAKE_ZEROED;
+}
+
+void wg_noise_handshake_clear(struct noise_handshake *handshake)
+{
+	down_write(&handshake->lock);
+	wg_index_hashtable_remove(
+			handshake->entry.peer->device->index_hashtable,
+			&handshake->entry);
+	handshake_zero(handshake);
+	up_write(&handshake->lock);
+}
+
+static struct noise_keypair *keypair_create(struct wg_peer *peer)
+{
+	struct noise_keypair *keypair = kzalloc_obj(*keypair);
+
+	if (unlikely(!keypair))
+		return NULL;
+	spin_lock_init(&keypair->receiving_counter.lock);
+	keypair->internal_id = atomic64_inc_return(&keypair_counter);
+	keypair->entry.type = INDEX_HASHTABLE_KEYPAIR;
+	keypair->entry.peer = peer;
+	kref_init(&keypair->refcount);
+	return keypair;
+}
+
+static void keypair_free_rcu(struct rcu_head *rcu)
+{
+	kfree_sensitive(container_of(rcu, struct noise_keypair, rcu));
+}
+
+static void keypair_free_kref(struct kref *kref)
+{
+	struct noise_keypair *keypair =
+		container_of(kref, struct noise_keypair, refcount);
+
+	net_dbg_ratelimited("%s: Keypair %llu destroyed for peer %llu\n",
+			    keypair->entry.peer->device->dev->name,
+			    keypair->internal_id,
+			    keypair->entry.peer->internal_id);
+	wg_index_hashtable_remove(keypair->entry.peer->device->index_hashtable,
+				  &keypair->entry);
+	call_rcu(&keypair->rcu, keypair_free_rcu);
+}
+
+void wg_noise_keypair_put(struct noise_keypair *keypair, bool unreference_now)
+{
+	if (unlikely(!keypair))
+		return;
+	if (unlikely(unreference_now))
+		wg_index_hashtable_remove(
+			keypair->entry.peer->device->index_hashtable,
+			&keypair->entry);
+	kref_put(&keypair->refcount, keypair_free_kref);
+}
+
+struct noise_keypair *wg_noise_keypair_get(struct noise_keypair *keypair)
+{
+	RCU_LOCKDEP_WARN(!rcu_read_lock_bh_held(),
+		"Taking noise keypair reference without holding the RCU BH read lock");
+	if (unlikely(!keypair || !kref_get_unless_zero(&keypair->refcount)))
+		return NULL;
+	return keypair;
+}
+
+void wg_noise_keypairs_clear(struct noise_keypairs *keypairs)
+{
+	struct noise_keypair *old;
+
+	spin_lock_bh(&keypairs->keypair_update_lock);
+
+	/* We zero the next_keypair before zeroing the others, so that
+	 * wg_noise_received_with_keypair returns early before subsequent ones
+	 * are zeroed.
+	 */
+	old = rcu_dereference_protected(keypairs->next_keypair,
+		lockdep_is_held(&keypairs->keypair_update_lock));
+	RCU_INIT_POINTER(keypairs->next_keypair, NULL);
+	wg_noise_keypair_put(old, true);
+
+	old = rcu_dereference_protected(keypairs->previous_keypair,
+		lockdep_is_held(&keypairs->keypair_update_lock));
+	RCU_INIT_POINTER(keypairs->previous_keypair, NULL);
+	wg_noise_keypair_put(old, true);
+
+	old = rcu_dereference_protected(keypairs->current_keypair,
+		lockdep_is_held(&keypairs->keypair_update_lock));
+	RCU_INIT_POINTER(keypairs->current_keypair, NULL);
+	wg_noise_keypair_put(old, true);
+
+	spin_unlock_bh(&keypairs->keypair_update_lock);
+}
+
+void wg_noise_expire_current_peer_keypairs(struct wg_peer *peer)
+{
+	struct noise_keypair *keypair;
+
+	wg_noise_handshake_clear(&peer->handshake);
+	wg_noise_reset_last_sent_handshake(&peer->last_sent_handshake);
+
+	spin_lock_bh(&peer->keypairs.keypair_update_lock);
+	keypair = rcu_dereference_protected(peer->keypairs.next_keypair,
+			lockdep_is_held(&peer->keypairs.keypair_update_lock));
+	if (keypair)
+		keypair->sending.is_valid = false;
+	keypair = rcu_dereference_protected(peer->keypairs.current_keypair,
+			lockdep_is_held(&peer->keypairs.keypair_update_lock));
+	if (keypair)
+		keypair->sending.is_valid = false;
+	spin_unlock_bh(&peer->keypairs.keypair_update_lock);
+}
+
+static void add_new_keypair(struct noise_keypairs *keypairs,
+			    struct noise_keypair *new_keypair)
+{
+	struct noise_keypair *previous_keypair, *next_keypair, *current_keypair;
+
+	spin_lock_bh(&keypairs->keypair_update_lock);
+	previous_keypair = rcu_dereference_protected(keypairs->previous_keypair,
+		lockdep_is_held(&keypairs->keypair_update_lock));
+	next_keypair = rcu_dereference_protected(keypairs->next_keypair,
+		lockdep_is_held(&keypairs->keypair_update_lock));
+	current_keypair = rcu_dereference_protected(keypairs->current_keypair,
+		lockdep_is_held(&keypairs->keypair_update_lock));
+	if (new_keypair->i_am_the_initiator) {
+		/* If we're the initiator, it means we've sent a handshake, and
+		 * received a confirmation response, which means this new
+		 * keypair can now be used.
+		 */
+		if (next_keypair) {
+			/* If there already was a next keypair pending, we
+			 * demote it to be the previous keypair, and free the
+			 * existing current. Note that this means KCI can result
+			 * in this transition. It would perhaps be more sound to
+			 * always just get rid of the unused next keypair
+			 * instead of putting it in the previous slot, but this
+			 * might be a bit less robust. Something to think about
+			 * for the future.
+			 */
+			RCU_INIT_POINTER(keypairs->next_keypair, NULL);
+			rcu_assign_pointer(keypairs->previous_keypair,
+					   next_keypair);
+			wg_noise_keypair_put(current_keypair, true);
+		} else /* If there wasn't an existing next keypair, we replace
+			* the previous with the current one.
+			*/
+			rcu_assign_pointer(keypairs->previous_keypair,
+					   current_keypair);
+		/* At this point we can get rid of the old previous keypair, and
+		 * set up the new keypair.
+		 */
+		wg_noise_keypair_put(previous_keypair, true);
+		rcu_assign_pointer(keypairs->current_keypair, new_keypair);
+	} else {
+		/* If we're the responder, it means we can't use the new keypair
+		 * until we receive confirmation via the first data packet, so
+		 * we get rid of the existing previous one, the possibly
+		 * existing next one, and slide in the new next one.
+		 */
+		rcu_assign_pointer(keypairs->next_keypair, new_keypair);
+		wg_noise_keypair_put(next_keypair, true);
+		RCU_INIT_POINTER(keypairs->previous_keypair, NULL);
+		wg_noise_keypair_put(previous_keypair, true);
+	}
+	spin_unlock_bh(&keypairs->keypair_update_lock);
+}
+
+bool wg_noise_received_with_keypair(struct noise_keypairs *keypairs,
+				    struct noise_keypair *received_keypair)
+{
+	struct noise_keypair *old_keypair;
+	bool key_is_new;
+
+	/* We first check without taking the spinlock. */
+	key_is_new = received_keypair ==
+		     rcu_access_pointer(keypairs->next_keypair);
+	if (likely(!key_is_new))
+		return false;
+
+	spin_lock_bh(&keypairs->keypair_update_lock);
+	/* After locking, we double check that things didn't change from
+	 * beneath us.
+	 */
+	if (unlikely(received_keypair !=
+		    rcu_dereference_protected(keypairs->next_keypair,
+			    lockdep_is_held(&keypairs->keypair_update_lock)))) {
+		spin_unlock_bh(&keypairs->keypair_update_lock);
+		return false;
+	}
+
+	/* When we've finally received the confirmation, we slide the next
+	 * into the current, the current into the previous, and get rid of
+	 * the old previous.
+	 */
+	old_keypair = rcu_dereference_protected(keypairs->previous_keypair,
+		lockdep_is_held(&keypairs->keypair_update_lock));
+	rcu_assign_pointer(keypairs->previous_keypair,
+		rcu_dereference_protected(keypairs->current_keypair,
+			lockdep_is_held(&keypairs->keypair_update_lock)));
+	wg_noise_keypair_put(old_keypair, true);
+	rcu_assign_pointer(keypairs->current_keypair, received_keypair);
+	RCU_INIT_POINTER(keypairs->next_keypair, NULL);
+
+	spin_unlock_bh(&keypairs->keypair_update_lock);
+	return true;
+}
+
+/* Must hold static_identity->lock */
+void wg_noise_set_static_identity_private_key(
+	struct noise_static_identity *static_identity,
+	const u8 private_key[NOISE_PUBLIC_KEY_LEN])
+{
+	memcpy(static_identity->static_private, private_key,
+	       NOISE_PUBLIC_KEY_LEN);
+	curve25519_clamp_secret(static_identity->static_private);
+	static_identity->has_identity = curve25519_generate_public(
+		static_identity->static_public, private_key);
+}
+
+static void hmac(u8 *out, const u8 *in, const u8 *key, const size_t inlen, const size_t keylen)
+{
+	struct blake2s_ctx blake;
+	u8 x_key[BLAKE2S_BLOCK_SIZE] __aligned(__alignof__(u32)) = { 0 };
+	u8 i_hash[BLAKE2S_HASH_SIZE] __aligned(__alignof__(u32));
+	int i;
+
+	if (keylen > BLAKE2S_BLOCK_SIZE) {
+		blake2s_init(&blake, BLAKE2S_HASH_SIZE);
+		blake2s_update(&blake, key, keylen);
+		blake2s_final(&blake, x_key);
+	} else
+		memcpy(x_key, key, keylen);
+
+	for (i = 0; i < BLAKE2S_BLOCK_SIZE; ++i)
+		x_key[i] ^= 0x36;
+
+	blake2s_init(&blake, BLAKE2S_HASH_SIZE);
+	blake2s_update(&blake, x_key, BLAKE2S_BLOCK_SIZE);
+	blake2s_update(&blake, in, inlen);
+	blake2s_final(&blake, i_hash);
+
+	for (i = 0; i < BLAKE2S_BLOCK_SIZE; ++i)
+		x_key[i] ^= 0x5c ^ 0x36;
+
+	blake2s_init(&blake, BLAKE2S_HASH_SIZE);
+	blake2s_update(&blake, x_key, BLAKE2S_BLOCK_SIZE);
+	blake2s_update(&blake, i_hash, BLAKE2S_HASH_SIZE);
+	blake2s_final(&blake, i_hash);
+
+	memcpy(out, i_hash, BLAKE2S_HASH_SIZE);
+	memzero_explicit(x_key, BLAKE2S_BLOCK_SIZE);
+	memzero_explicit(i_hash, BLAKE2S_HASH_SIZE);
+}
+
+/* This is Hugo Krawczyk's HKDF:
+ *  - https://eprint.iacr.org/2010/264.pdf
+ *  - https://tools.ietf.org/html/rfc5869
+ */
+static void kdf(u8 *first_dst, u8 *second_dst, u8 *third_dst, const u8 *data,
+		size_t first_len, size_t second_len, size_t third_len,
+		size_t data_len, const u8 chaining_key[NOISE_HASH_LEN])
+{
+	u8 output[BLAKE2S_HASH_SIZE + 1];
+	u8 secret[BLAKE2S_HASH_SIZE];
+
+	WARN_ON(IS_ENABLED(DEBUG) &&
+		(first_len > BLAKE2S_HASH_SIZE ||
+		 second_len > BLAKE2S_HASH_SIZE ||
+		 third_len > BLAKE2S_HASH_SIZE ||
+		 ((second_len || second_dst || third_len || third_dst) &&
+		  (!first_len || !first_dst)) ||
+		 ((third_len || third_dst) && (!second_len || !second_dst))));
+
+	/* Extract entropy from data into secret */
+	hmac(secret, data, chaining_key, data_len, NOISE_HASH_LEN);
+
+	if (!first_dst || !first_len)
+		goto out;
+
+	/* Expand first key: key = secret, data = 0x1 */
+	output[0] = 1;
+	hmac(output, output, secret, 1, BLAKE2S_HASH_SIZE);
+	memcpy(first_dst, output, first_len);
+
+	if (!second_dst || !second_len)
+		goto out;
+
+	/* Expand second key: key = secret, data = first-key || 0x2 */
+	output[BLAKE2S_HASH_SIZE] = 2;
+	hmac(output, output, secret, BLAKE2S_HASH_SIZE + 1, BLAKE2S_HASH_SIZE);
+	memcpy(second_dst, output, second_len);
+
+	if (!third_dst || !third_len)
+		goto out;
+
+	/* Expand third key: key = secret, data = second-key || 0x3 */
+	output[BLAKE2S_HASH_SIZE] = 3;
+	hmac(output, output, secret, BLAKE2S_HASH_SIZE + 1, BLAKE2S_HASH_SIZE);
+	memcpy(third_dst, output, third_len);
+
+out:
+	/* Clear sensitive data from stack */
+	memzero_explicit(secret, BLAKE2S_HASH_SIZE);
+	memzero_explicit(output, BLAKE2S_HASH_SIZE + 1);
+}
+
+static void derive_keys(struct noise_symmetric_key *first_dst,
+			struct noise_symmetric_key *second_dst,
+			const u8 chaining_key[NOISE_HASH_LEN])
+{
+	u64 birthdate = ktime_get_coarse_boottime_ns();
+	kdf(first_dst->key, second_dst->key, NULL, NULL,
+	    NOISE_SYMMETRIC_KEY_LEN, NOISE_SYMMETRIC_KEY_LEN, 0, 0,
+	    chaining_key);
+	first_dst->birthdate = second_dst->birthdate = birthdate;
+	first_dst->is_valid = second_dst->is_valid = true;
+}
+
+static bool __must_check mix_dh(u8 chaining_key[NOISE_HASH_LEN],
+				u8 key[NOISE_SYMMETRIC_KEY_LEN],
+				const u8 private[NOISE_PUBLIC_KEY_LEN],
+				const u8 public[NOISE_PUBLIC_KEY_LEN])
+{
+	u8 dh_calculation[NOISE_PUBLIC_KEY_LEN];
+
+	if (unlikely(!curve25519(dh_calculation, private, public)))
+		return false;
+	kdf(chaining_key, key, NULL, dh_calculation, NOISE_HASH_LEN,
+	    NOISE_SYMMETRIC_KEY_LEN, 0, NOISE_PUBLIC_KEY_LEN, chaining_key);
+	memzero_explicit(dh_calculation, NOISE_PUBLIC_KEY_LEN);
+	return true;
+}
+
+static bool __must_check mix_precomputed_dh(u8 chaining_key[NOISE_HASH_LEN],
+					    u8 key[NOISE_SYMMETRIC_KEY_LEN],
+					    const u8 precomputed[NOISE_PUBLIC_KEY_LEN])
+{
+	static u8 zero_point[NOISE_PUBLIC_KEY_LEN];
+	if (unlikely(!crypto_memneq(precomputed, zero_point, NOISE_PUBLIC_KEY_LEN)))
+		return false;
+	kdf(chaining_key, key, NULL, precomputed, NOISE_HASH_LEN,
+	    NOISE_SYMMETRIC_KEY_LEN, 0, NOISE_PUBLIC_KEY_LEN,
+	    chaining_key);
+	return true;
+}
+
+static void mix_hash(u8 hash[NOISE_HASH_LEN], const u8 *src, size_t src_len)
+{
+	struct blake2s_ctx blake;
+
+	blake2s_init(&blake, NOISE_HASH_LEN);
+	blake2s_update(&blake, hash, NOISE_HASH_LEN);
+	blake2s_update(&blake, src, src_len);
+	blake2s_final(&blake, hash);
+}
+
+static void mix_psk(u8 chaining_key[NOISE_HASH_LEN], u8 hash[NOISE_HASH_LEN],
+		    u8 key[NOISE_SYMMETRIC_KEY_LEN],
+		    const u8 psk[NOISE_SYMMETRIC_KEY_LEN])
+{
+	u8 temp_hash[NOISE_HASH_LEN];
+
+	kdf(chaining_key, temp_hash, key, psk, NOISE_HASH_LEN, NOISE_HASH_LEN,
+	    NOISE_SYMMETRIC_KEY_LEN, NOISE_SYMMETRIC_KEY_LEN, chaining_key);
+	mix_hash(hash, temp_hash, NOISE_HASH_LEN);
+	memzero_explicit(temp_hash, NOISE_HASH_LEN);
+}
+
+static void handshake_init(u8 chaining_key[NOISE_HASH_LEN],
+			   u8 hash[NOISE_HASH_LEN],
+			   const u8 remote_static[NOISE_PUBLIC_KEY_LEN])
+{
+	memcpy(hash, handshake_init_hash, NOISE_HASH_LEN);
+	memcpy(chaining_key, handshake_init_chaining_key, NOISE_HASH_LEN);
+	mix_hash(hash, remote_static, NOISE_PUBLIC_KEY_LEN);
+}
+
+static void message_encrypt(u8 *dst_ciphertext, const u8 *src_plaintext,
+			    size_t src_len, u8 key[NOISE_SYMMETRIC_KEY_LEN],
+			    u8 hash[NOISE_HASH_LEN])
+{
+	chacha20poly1305_encrypt(dst_ciphertext, src_plaintext, src_len, hash,
+				 NOISE_HASH_LEN,
+				 0 /* Always zero for Noise_IK */, key);
+	mix_hash(hash, dst_ciphertext, noise_encrypted_len(src_len));
+}
+
+static bool message_decrypt(u8 *dst_plaintext, const u8 *src_ciphertext,
+			    size_t src_len, u8 key[NOISE_SYMMETRIC_KEY_LEN],
+			    u8 hash[NOISE_HASH_LEN])
+{
+	if (!chacha20poly1305_decrypt(dst_plaintext, src_ciphertext, src_len,
+				      hash, NOISE_HASH_LEN,
+				      0 /* Always zero for Noise_IK */, key))
+		return false;
+	mix_hash(hash, src_ciphertext, src_len);
+	return true;
+}
+
+static void message_ephemeral(u8 ephemeral_dst[NOISE_PUBLIC_KEY_LEN],
+			      const u8 ephemeral_src[NOISE_PUBLIC_KEY_LEN],
+			      u8 chaining_key[NOISE_HASH_LEN],
+			      u8 hash[NOISE_HASH_LEN])
+{
+	if (ephemeral_dst != ephemeral_src)
+		memcpy(ephemeral_dst, ephemeral_src, NOISE_PUBLIC_KEY_LEN);
+	mix_hash(hash, ephemeral_src, NOISE_PUBLIC_KEY_LEN);
+	kdf(chaining_key, NULL, NULL, ephemeral_src, NOISE_HASH_LEN, 0, 0,
+	    NOISE_PUBLIC_KEY_LEN, chaining_key);
+}
+
+static void tai64n_now(u8 output[NOISE_TIMESTAMP_LEN])
+{
+	struct timespec64 now;
+
+	ktime_get_real_ts64(&now);
+
+	/* In order to prevent some sort of infoleak from precise timers, we
+	 * round down the nanoseconds part to the closest rounded-down power of
+	 * two to the maximum initiations per second allowed anyway by the
+	 * implementation.
+	 */
+	now.tv_nsec = ALIGN_DOWN(now.tv_nsec,
+		rounddown_pow_of_two(NSEC_PER_SEC / INITIATIONS_PER_SECOND));
+
+	/* https://cr.yp.to/libtai/tai64.html */
+	*(__be64 *)output = cpu_to_be64(0x400000000000000aULL + now.tv_sec);
+	*(__be32 *)(output + sizeof(__be64)) = cpu_to_be32(now.tv_nsec);
+}
+
+bool
+wg_noise_handshake_create_initiation(struct message_handshake_initiation *dst,
+				     struct noise_handshake *handshake)
+{
+	u8 timestamp[NOISE_TIMESTAMP_LEN];
+	u8 key[NOISE_SYMMETRIC_KEY_LEN];
+	bool ret = false;
+
+	/* We need to wait for crng _before_ taking any locks, since
+	 * curve25519_generate_secret uses get_random_bytes_wait.
+	 */
+	wait_for_random_bytes();
+
+	down_read(&handshake->static_identity->lock);
+	down_write(&handshake->lock);
+
+	if (unlikely(!handshake->static_identity->has_identity))
+		goto out;
+
+	dst->header.type = cpu_to_le32(MESSAGE_HANDSHAKE_INITIATION);
+
+	handshake_init(handshake->chaining_key, handshake->hash,
+		       handshake->remote_static);
+
+	/* e */
+	curve25519_generate_secret(handshake->ephemeral_private);
+	if (!curve25519_generate_public(dst->unencrypted_ephemeral,
+					handshake->ephemeral_private))
+		goto out;
+	message_ephemeral(dst->unencrypted_ephemeral,
+			  dst->unencrypted_ephemeral, handshake->chaining_key,
+			  handshake->hash);
+
+	/* es */
+	if (!mix_dh(handshake->chaining_key, key, handshake->ephemeral_private,
+		    handshake->remote_static))
+		goto out;
+
+	/* s */
+	message_encrypt(dst->encrypted_static,
+			handshake->static_identity->static_public,
+			NOISE_PUBLIC_KEY_LEN, key, handshake->hash);
+
+	/* ss */
+	if (!mix_precomputed_dh(handshake->chaining_key, key,
+				handshake->precomputed_static_static))
+		goto out;
+
+	/* {t} */
+	tai64n_now(timestamp);
+	message_encrypt(dst->encrypted_timestamp, timestamp,
+			NOISE_TIMESTAMP_LEN, key, handshake->hash);
+
+	dst->sender_index = wg_index_hashtable_insert(
+		handshake->entry.peer->device->index_hashtable,
+		&handshake->entry);
+
+	handshake->state = HANDSHAKE_CREATED_INITIATION;
+	ret = true;
+
+out:
+	up_write(&handshake->lock);
+	up_read(&handshake->static_identity->lock);
+	memzero_explicit(key, NOISE_SYMMETRIC_KEY_LEN);
+	return ret;
+}
+
+struct wg_peer *
+wg_noise_handshake_consume_initiation(struct message_handshake_initiation *src,
+				      struct wg_device *wg)
+{
+	struct wg_peer *peer = NULL, *ret_peer = NULL;
+	struct noise_handshake *handshake;
+	bool replay_attack, flood_attack;
+	u8 key[NOISE_SYMMETRIC_KEY_LEN];
+	u8 chaining_key[NOISE_HASH_LEN];
+	u8 hash[NOISE_HASH_LEN];
+	u8 s[NOISE_PUBLIC_KEY_LEN];
+	u8 e[NOISE_PUBLIC_KEY_LEN];
+	u8 t[NOISE_TIMESTAMP_LEN];
+	u64 initiation_consumption;
+
+	down_read(&wg->static_identity.lock);
+	if (unlikely(!wg->static_identity.has_identity))
+		goto out;
+
+	handshake_init(chaining_key, hash, wg->static_identity.static_public);
+
+	/* e */
+	message_ephemeral(e, src->unencrypted_ephemeral, chaining_key, hash);
+
+	/* es */
+	if (!mix_dh(chaining_key, key, wg->static_identity.static_private, e))
+		goto out;
+
+	/* s */
+	if (!message_decrypt(s, src->encrypted_static,
+			     sizeof(src->encrypted_static), key, hash))
+		goto out;
+
+	/* Lookup which peer we're actually talking to */
+	peer = wg_pubkey_hashtable_lookup(wg->peer_hashtable, s);
+	if (!peer)
+		goto out;
+	handshake = &peer->handshake;
+
+	/* ss */
+	if (!mix_precomputed_dh(chaining_key, key,
+				handshake->precomputed_static_static))
+	    goto out;
+
+	/* {t} */
+	if (!message_decrypt(t, src->encrypted_timestamp,
+			     sizeof(src->encrypted_timestamp), key, hash))
+		goto out;
+
+	down_read(&handshake->lock);
+	replay_attack = memcmp(t, handshake->latest_timestamp,
+			       NOISE_TIMESTAMP_LEN) <= 0;
+	flood_attack = (s64)handshake->last_initiation_consumption +
+			       NSEC_PER_SEC / INITIATIONS_PER_SECOND >
+		       (s64)ktime_get_coarse_boottime_ns();
+	up_read(&handshake->lock);
+	if (replay_attack || flood_attack)
+		goto out;
+
+	/* Success! Copy everything to peer */
+	down_write(&handshake->lock);
+	memcpy(handshake->remote_ephemeral, e, NOISE_PUBLIC_KEY_LEN);
+	if (memcmp(t, handshake->latest_timestamp, NOISE_TIMESTAMP_LEN) > 0)
+		memcpy(handshake->latest_timestamp, t, NOISE_TIMESTAMP_LEN);
+	memcpy(handshake->hash, hash, NOISE_HASH_LEN);
+	memcpy(handshake->chaining_key, chaining_key, NOISE_HASH_LEN);
+	handshake->remote_index = src->sender_index;
+	initiation_consumption = ktime_get_coarse_boottime_ns();
+	if ((s64)(handshake->last_initiation_consumption - initiation_consumption) < 0)
+		handshake->last_initiation_consumption = initiation_consumption;
+	handshake->state = HANDSHAKE_CONSUMED_INITIATION;
+	up_write(&handshake->lock);
+	ret_peer = peer;
+
+out:
+	memzero_explicit(key, NOISE_SYMMETRIC_KEY_LEN);
+	memzero_explicit(hash, NOISE_HASH_LEN);
+	memzero_explicit(chaining_key, NOISE_HASH_LEN);
+	up_read(&wg->static_identity.lock);
+	if (!ret_peer)
+		wg_peer_put(peer);
+	return ret_peer;
+}
+
+bool wg_noise_handshake_create_response(struct message_handshake_response *dst,
+					struct noise_handshake *handshake)
+{
+	u8 key[NOISE_SYMMETRIC_KEY_LEN];
+	bool ret = false;
+
+	/* We need to wait for crng _before_ taking any locks, since
+	 * curve25519_generate_secret uses get_random_bytes_wait.
+	 */
+	wait_for_random_bytes();
+
+	down_read(&handshake->static_identity->lock);
+	down_write(&handshake->lock);
+
+	if (handshake->state != HANDSHAKE_CONSUMED_INITIATION)
+		goto out;
+
+	dst->header.type = cpu_to_le32(MESSAGE_HANDSHAKE_RESPONSE);
+	dst->receiver_index = handshake->remote_index;
+
+	/* e */
+	curve25519_generate_secret(handshake->ephemeral_private);
+	if (!curve25519_generate_public(dst->unencrypted_ephemeral,
+					handshake->ephemeral_private))
+		goto out;
+	message_ephemeral(dst->unencrypted_ephemeral,
+			  dst->unencrypted_ephemeral, handshake->chaining_key,
+			  handshake->hash);
+
+	/* ee */
+	if (!mix_dh(handshake->chaining_key, NULL, handshake->ephemeral_private,
+		    handshake->remote_ephemeral))
+		goto out;
+
+	/* se */
+	if (!mix_dh(handshake->chaining_key, NULL, handshake->ephemeral_private,
+		    handshake->remote_static))
+		goto out;
+
+	/* psk */
+	mix_psk(handshake->chaining_key, handshake->hash, key,
+		handshake->preshared_key);
+
+	/* {} */
+	message_encrypt(dst->encrypted_nothing, NULL, 0, key, handshake->hash);
+
+	dst->sender_index = wg_index_hashtable_insert(
+		handshake->entry.peer->device->index_hashtable,
+		&handshake->entry);
+
+	handshake->state = HANDSHAKE_CREATED_RESPONSE;
+	ret = true;
+
+out:
+	up_write(&handshake->lock);
+	up_read(&handshake->static_identity->lock);
+	memzero_explicit(key, NOISE_SYMMETRIC_KEY_LEN);
+	return ret;
+}
+
+struct wg_peer *
+wg_noise_handshake_consume_response(struct message_handshake_response *src,
+				    struct wg_device *wg)
+{
+	enum noise_handshake_state state = HANDSHAKE_ZEROED;
+	struct wg_peer *peer = NULL, *ret_peer = NULL;
+	struct noise_handshake *handshake;
+	u8 key[NOISE_SYMMETRIC_KEY_LEN];
+	u8 hash[NOISE_HASH_LEN];
+	u8 chaining_key[NOISE_HASH_LEN];
+	u8 e[NOISE_PUBLIC_KEY_LEN];
+	u8 ephemeral_private[NOISE_PUBLIC_KEY_LEN];
+	u8 static_private[NOISE_PUBLIC_KEY_LEN];
+	u8 preshared_key[NOISE_SYMMETRIC_KEY_LEN];
+
+	down_read(&wg->static_identity.lock);
+
+	if (unlikely(!wg->static_identity.has_identity))
+		goto out;
+
+	handshake = (struct noise_handshake *)wg_index_hashtable_lookup(
+		wg->index_hashtable, INDEX_HASHTABLE_HANDSHAKE,
+		src->receiver_index, &peer);
+	if (unlikely(!handshake))
+		goto out;
+
+	down_read(&handshake->lock);
+	state = handshake->state;
+	memcpy(hash, handshake->hash, NOISE_HASH_LEN);
+	memcpy(chaining_key, handshake->chaining_key, NOISE_HASH_LEN);
+	memcpy(ephemeral_private, handshake->ephemeral_private,
+	       NOISE_PUBLIC_KEY_LEN);
+	memcpy(preshared_key, handshake->preshared_key,
+	       NOISE_SYMMETRIC_KEY_LEN);
+	up_read(&handshake->lock);
+
+	if (state != HANDSHAKE_CREATED_INITIATION)
+		goto fail;
+
+	/* e */
+	message_ephemeral(e, src->unencrypted_ephemeral, chaining_key, hash);
+
+	/* ee */
+	if (!mix_dh(chaining_key, NULL, ephemeral_private, e))
+		goto fail;
+
+	/* se */
+	if (!mix_dh(chaining_key, NULL, wg->static_identity.static_private, e))
+		goto fail;
+
+	/* psk */
+	mix_psk(chaining_key, hash, key, preshared_key);
+
+	/* {} */
+	if (!message_decrypt(NULL, src->encrypted_nothing,
+			     sizeof(src->encrypted_nothing), key, hash))
+		goto fail;
+
+	/* Success! Copy everything to peer */
+	down_write(&handshake->lock);
+	/* It's important to check that the state is still the same, while we
+	 * have an exclusive lock.
+	 */
+	if (handshake->state != state) {
+		up_write(&handshake->lock);
+		goto fail;
+	}
+	memcpy(handshake->remote_ephemeral, e, NOISE_PUBLIC_KEY_LEN);
+	memcpy(handshake->hash, hash, NOISE_HASH_LEN);
+	memcpy(handshake->chaining_key, chaining_key, NOISE_HASH_LEN);
+	handshake->remote_index = src->sender_index;
+	handshake->state = HANDSHAKE_CONSUMED_RESPONSE;
+	up_write(&handshake->lock);
+	ret_peer = peer;
+	goto out;
+
+fail:
+	wg_peer_put(peer);
+out:
+	memzero_explicit(key, NOISE_SYMMETRIC_KEY_LEN);
+	memzero_explicit(hash, NOISE_HASH_LEN);
+	memzero_explicit(chaining_key, NOISE_HASH_LEN);
+	memzero_explicit(ephemeral_private, NOISE_PUBLIC_KEY_LEN);
+	memzero_explicit(static_private, NOISE_PUBLIC_KEY_LEN);
+	memzero_explicit(preshared_key, NOISE_SYMMETRIC_KEY_LEN);
+	up_read(&wg->static_identity.lock);
+	return ret_peer;
+}
+
+bool wg_noise_handshake_begin_session(struct noise_handshake *handshake,
+				      struct noise_keypairs *keypairs)
+{
+	struct noise_keypair *new_keypair;
+	bool ret = false;
+
+	down_write(&handshake->lock);
+	if (handshake->state != HANDSHAKE_CREATED_RESPONSE &&
+	    handshake->state != HANDSHAKE_CONSUMED_RESPONSE)
+		goto out;
+
+	new_keypair = keypair_create(handshake->entry.peer);
+	if (!new_keypair)
+		goto out;
+	new_keypair->i_am_the_initiator = handshake->state ==
+					  HANDSHAKE_CONSUMED_RESPONSE;
+	new_keypair->remote_index = handshake->remote_index;
+
+	if (new_keypair->i_am_the_initiator)
+		derive_keys(&new_keypair->sending, &new_keypair->receiving,
+			    handshake->chaining_key);
+	else
+		derive_keys(&new_keypair->receiving, &new_keypair->sending,
+			    handshake->chaining_key);
+
+	handshake_zero(handshake);
+	rcu_read_lock_bh();
+	if (likely(!READ_ONCE(container_of(handshake, struct wg_peer,
+					   handshake)->is_dead))) {
+		add_new_keypair(keypairs, new_keypair);
+		net_dbg_ratelimited("%s: Keypair %llu created for peer %llu\n",
+				    handshake->entry.peer->device->dev->name,
+				    new_keypair->internal_id,
+				    handshake->entry.peer->internal_id);
+		ret = wg_index_hashtable_replace(
+			handshake->entry.peer->device->index_hashtable,
+			&handshake->entry, &new_keypair->entry);
+	} else {
+		kfree_sensitive(new_keypair);
+	}
+	rcu_read_unlock_bh();
+
+out:
+	up_write(&handshake->lock);
+	return ret;
+}

linux-7.2.3/drivers/net/wireguard/noise.h

@@ -0,0 +1,135 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+#ifndef _WG_NOISE_H
+#define _WG_NOISE_H
+
+#include "messages.h"
+#include "peerlookup.h"
+
+#include <linux/types.h>
+#include <linux/spinlock.h>
+#include <linux/atomic.h>
+#include <linux/rwsem.h>
+#include <linux/mutex.h>
+#include <linux/kref.h>
+
+struct noise_replay_counter {
+	u64 counter;
+	spinlock_t lock;
+	unsigned long backtrack[COUNTER_BITS_TOTAL / BITS_PER_LONG];
+};
+
+struct noise_symmetric_key {
+	u8 key[NOISE_SYMMETRIC_KEY_LEN];
+	u64 birthdate;
+	bool is_valid;
+};
+
+struct noise_keypair {
+	struct index_hashtable_entry entry;
+	struct noise_symmetric_key sending;
+	atomic64_t sending_counter;
+	struct noise_symmetric_key receiving;
+	struct noise_replay_counter receiving_counter;
+	__le32 remote_index;
+	bool i_am_the_initiator;
+	struct kref refcount;
+	struct rcu_head rcu;
+	u64 internal_id;
+};
+
+struct noise_keypairs {
+	struct noise_keypair __rcu *current_keypair;
+	struct noise_keypair __rcu *previous_keypair;
+	struct noise_keypair __rcu *next_keypair;
+	spinlock_t keypair_update_lock;
+};
+
+struct noise_static_identity {
+	u8 static_public[NOISE_PUBLIC_KEY_LEN];
+	u8 static_private[NOISE_PUBLIC_KEY_LEN];
+	struct rw_semaphore lock;
+	bool has_identity;
+};
+
+enum noise_handshake_state {
+	HANDSHAKE_ZEROED,
+	HANDSHAKE_CREATED_INITIATION,
+	HANDSHAKE_CONSUMED_INITIATION,
+	HANDSHAKE_CREATED_RESPONSE,
+	HANDSHAKE_CONSUMED_RESPONSE
+};
+
+struct noise_handshake {
+	struct index_hashtable_entry entry;
+
+	enum noise_handshake_state state;
+	u64 last_initiation_consumption;
+
+	struct noise_static_identity *static_identity;
+
+	u8 ephemeral_private[NOISE_PUBLIC_KEY_LEN];
+	u8 remote_static[NOISE_PUBLIC_KEY_LEN];
+	u8 remote_ephemeral[NOISE_PUBLIC_KEY_LEN];
+	u8 precomputed_static_static[NOISE_PUBLIC_KEY_LEN];
+
+	u8 preshared_key[NOISE_SYMMETRIC_KEY_LEN];
+
+	u8 hash[NOISE_HASH_LEN];
+	u8 chaining_key[NOISE_HASH_LEN];
+
+	u8 latest_timestamp[NOISE_TIMESTAMP_LEN];
+	__le32 remote_index;
+
+	/* Protects all members except the immutable (after noise_handshake_
+	 * init): remote_static, precomputed_static_static, static_identity.
+	 */
+	struct rw_semaphore lock;
+};
+
+struct wg_device;
+
+void wg_noise_init(void);
+void wg_noise_handshake_init(struct noise_handshake *handshake,
+			     struct noise_static_identity *static_identity,
+			     const u8 peer_public_key[NOISE_PUBLIC_KEY_LEN],
+			     const u8 peer_preshared_key[NOISE_SYMMETRIC_KEY_LEN],
+			     struct wg_peer *peer);
+void wg_noise_handshake_clear(struct noise_handshake *handshake);
+static inline void wg_noise_reset_last_sent_handshake(atomic64_t *handshake_ns)
+{
+	atomic64_set(handshake_ns, ktime_get_coarse_boottime_ns() -
+				       (u64)(REKEY_TIMEOUT + 1) * NSEC_PER_SEC);
+}
+
+void wg_noise_keypair_put(struct noise_keypair *keypair, bool unreference_now);
+struct noise_keypair *wg_noise_keypair_get(struct noise_keypair *keypair);
+void wg_noise_keypairs_clear(struct noise_keypairs *keypairs);
+bool wg_noise_received_with_keypair(struct noise_keypairs *keypairs,
+				    struct noise_keypair *received_keypair);
+void wg_noise_expire_current_peer_keypairs(struct wg_peer *peer);
+
+void wg_noise_set_static_identity_private_key(
+	struct noise_static_identity *static_identity,
+	const u8 private_key[NOISE_PUBLIC_KEY_LEN]);
+void wg_noise_precompute_static_static(struct wg_peer *peer);
+
+bool
+wg_noise_handshake_create_initiation(struct message_handshake_initiation *dst,
+				     struct noise_handshake *handshake);
+struct wg_peer *
+wg_noise_handshake_consume_initiation(struct message_handshake_initiation *src,
+				      struct wg_device *wg);
+
+bool wg_noise_handshake_create_response(struct message_handshake_response *dst,
+					struct noise_handshake *handshake);
+struct wg_peer *
+wg_noise_handshake_consume_response(struct message_handshake_response *src,
+				    struct wg_device *wg);
+
+bool wg_noise_handshake_begin_session(struct noise_handshake *handshake,
+				      struct noise_keypairs *keypairs);
+
+#endif /* _WG_NOISE_H */

linux-7.2.3/drivers/net/wireguard/peer.c

@@ -0,0 +1,239 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include "peer.h"
+#include "device.h"
+#include "queueing.h"
+#include "timers.h"
+#include "peerlookup.h"
+#include "noise.h"
+
+#include <linux/kref.h>
+#include <linux/lockdep.h>
+#include <linux/rcupdate.h>
+#include <linux/list.h>
+
+static struct kmem_cache *peer_cache;
+static atomic64_t peer_counter = ATOMIC64_INIT(0);
+
+struct wg_peer *wg_peer_create(struct wg_device *wg,
+			       const u8 public_key[NOISE_PUBLIC_KEY_LEN],
+			       const u8 preshared_key[NOISE_SYMMETRIC_KEY_LEN])
+{
+	struct wg_peer *peer;
+	int ret = -ENOMEM;
+
+	lockdep_assert_held(&wg->device_update_lock);
+
+	if (wg->num_peers >= MAX_PEERS_PER_DEVICE)
+		return ERR_PTR(ret);
+
+	peer = kmem_cache_zalloc(peer_cache, GFP_KERNEL);
+	if (unlikely(!peer))
+		return ERR_PTR(ret);
+	if (unlikely(dst_cache_init(&peer->endpoint_cache, GFP_KERNEL)))
+		goto err;
+
+	peer->device = wg;
+	wg_noise_handshake_init(&peer->handshake, &wg->static_identity,
+				public_key, preshared_key, peer);
+	peer->internal_id = atomic64_inc_return(&peer_counter);
+	peer->serial_work_cpu = nr_cpumask_bits;
+	wg_cookie_init(&peer->latest_cookie);
+	wg_timers_init(peer);
+	wg_cookie_checker_precompute_peer_keys(peer);
+	spin_lock_init(&peer->keypairs.keypair_update_lock);
+	INIT_WORK(&peer->transmit_handshake_work, wg_packet_handshake_send_worker);
+	INIT_WORK(&peer->transmit_packet_work, wg_packet_tx_worker);
+	wg_prev_queue_init(&peer->tx_queue);
+	wg_prev_queue_init(&peer->rx_queue);
+	rwlock_init(&peer->endpoint_lock);
+	kref_init(&peer->refcount);
+	skb_queue_head_init(&peer->staged_packet_queue);
+	wg_noise_reset_last_sent_handshake(&peer->last_sent_handshake);
+	set_bit(NAPI_STATE_NO_BUSY_POLL, &peer->napi.state);
+	netif_napi_add(wg->dev, &peer->napi, wg_packet_rx_poll);
+	napi_enable(&peer->napi);
+	list_add_tail(&peer->peer_list, &wg->peer_list);
+	INIT_LIST_HEAD(&peer->allowedips_list);
+	wg_pubkey_hashtable_add(wg->peer_hashtable, peer);
+	++wg->num_peers;
+	pr_debug("%s: Peer %llu created\n", wg->dev->name, peer->internal_id);
+	return peer;
+
+err:
+	kmem_cache_free(peer_cache, peer);
+	return ERR_PTR(ret);
+}
+
+struct wg_peer *wg_peer_get_maybe_zero(struct wg_peer *peer)
+{
+	RCU_LOCKDEP_WARN(!rcu_read_lock_bh_held(),
+			 "Taking peer reference without holding the RCU read lock");
+	if (unlikely(!peer || !kref_get_unless_zero(&peer->refcount)))
+		return NULL;
+	return peer;
+}
+
+static void peer_make_dead(struct wg_peer *peer)
+{
+	/* Remove from configuration-time lookup structures. */
+	list_del_init(&peer->peer_list);
+	wg_allowedips_remove_by_peer(&peer->device->peer_allowedips, peer,
+				     &peer->device->device_update_lock);
+	wg_pubkey_hashtable_remove(peer->device->peer_hashtable, peer);
+
+	/* Mark as dead, so that we don't allow jumping contexts after. */
+	WRITE_ONCE(peer->is_dead, true);
+
+	/* The caller must now synchronize_net() for this to take effect. */
+}
+
+static void peer_remove_after_dead(struct wg_peer *peer)
+{
+	WARN_ON(!peer->is_dead);
+
+	/* No more keypairs can be created for this peer, since is_dead protects
+	 * add_new_keypair, so we can now destroy existing ones.
+	 */
+	wg_noise_keypairs_clear(&peer->keypairs);
+
+	/* Destroy all ongoing timers that were in-flight at the beginning of
+	 * this function.
+	 */
+	wg_timers_stop(peer);
+
+	/* The transition between packet encryption/decryption queues isn't
+	 * guarded by is_dead, but each reference's life is strictly bounded by
+	 * two generations: once for parallel crypto and once for serial
+	 * ingestion, so we can simply flush twice, and be sure that we no
+	 * longer have references inside these queues.
+	 */
+
+	/* a) For encrypt/decrypt. */
+	flush_workqueue(peer->device->packet_crypt_wq);
+	/* b.1) For send (but not receive, since that's napi). */
+	flush_workqueue(peer->device->packet_crypt_wq);
+	/* b.2.1) For receive (but not send, since that's wq). */
+	napi_disable(&peer->napi);
+	/* b.2.1) It's now safe to remove the napi struct, which must be done
+	 * here from process context.
+	 */
+	netif_napi_del(&peer->napi);
+
+	/* Ensure any workstructs we own (like transmit_handshake_work or
+	 * clear_peer_work) no longer are in use.
+	 */
+	flush_workqueue(peer->device->handshake_send_wq);
+
+	/* After the above flushes, a peer might still be active in a few
+	 * different contexts: 1) from xmit(), before hitting is_dead and
+	 * returning, 2) from wg_packet_consume_data(), before hitting is_dead
+	 * and returning, 3) from wg_receive_handshake_packet() after a point
+	 * where it has processed an incoming handshake packet, but where
+	 * all calls to pass it off to timers fails because of is_dead. We won't
+	 * have new references in (1) eventually, because we're removed from
+	 * allowedips; we won't have new references in (2) eventually, because
+	 * wg_index_hashtable_lookup will always return NULL, since we removed
+	 * all existing keypairs and no more can be created; we won't have new
+	 * references in (3) eventually, because we're removed from the pubkey
+	 * hash table, which allows for a maximum of one handshake response,
+	 * via the still-uncleared index hashtable entry, but not more than one,
+	 * and in wg_cookie_message_consume, the lookup eventually gets a peer
+	 * with a refcount of zero, so no new reference is taken.
+	 */
+
+	--peer->device->num_peers;
+	wg_peer_put(peer);
+}
+
+/* We have a separate "remove" function make sure that all active places where
+ * a peer is currently operating will eventually come to an end and not pass
+ * their reference onto another context.
+ */
+void wg_peer_remove(struct wg_peer *peer)
+{
+	if (unlikely(!peer))
+		return;
+	lockdep_assert_held(&peer->device->device_update_lock);
+
+	peer_make_dead(peer);
+	synchronize_net();
+	peer_remove_after_dead(peer);
+}
+
+void wg_peer_remove_all(struct wg_device *wg)
+{
+	struct wg_peer *peer, *temp;
+	LIST_HEAD(dead_peers);
+
+	lockdep_assert_held(&wg->device_update_lock);
+
+	/* Avoid having to traverse individually for each one. */
+	wg_allowedips_free(&wg->peer_allowedips, &wg->device_update_lock);
+
+	list_for_each_entry_safe(peer, temp, &wg->peer_list, peer_list) {
+		peer_make_dead(peer);
+		list_add_tail(&peer->peer_list, &dead_peers);
+	}
+	synchronize_net();
+	list_for_each_entry_safe(peer, temp, &dead_peers, peer_list)
+		peer_remove_after_dead(peer);
+}
+
+static void rcu_release(struct rcu_head *rcu)
+{
+	struct wg_peer *peer = container_of(rcu, struct wg_peer, rcu);
+
+	dst_cache_destroy(&peer->endpoint_cache);
+	WARN_ON(wg_prev_queue_peek(&peer->tx_queue) || wg_prev_queue_peek(&peer->rx_queue));
+
+	/* The final zeroing takes care of clearing any remaining handshake key
+	 * material and other potentially sensitive information.
+	 */
+	memzero_explicit(peer, sizeof(*peer));
+	kmem_cache_free(peer_cache, peer);
+}
+
+static void kref_release(struct kref *refcount)
+{
+	struct wg_peer *peer = container_of(refcount, struct wg_peer, refcount);
+
+	pr_debug("%s: Peer %llu (%pISpfsc) destroyed\n",
+		 peer->device->dev->name, peer->internal_id,
+		 &peer->endpoint.addr);
+
+	/* Remove ourself from dynamic runtime lookup structures, now that the
+	 * last reference is gone.
+	 */
+	wg_index_hashtable_remove(peer->device->index_hashtable,
+				  &peer->handshake.entry);
+
+	/* Remove any lingering packets that didn't have a chance to be
+	 * transmitted.
+	 */
+	wg_packet_purge_staged_packets(peer);
+
+	/* Free the memory used. */
+	call_rcu(&peer->rcu, rcu_release);
+}
+
+void wg_peer_put(struct wg_peer *peer)
+{
+	if (unlikely(!peer))
+		return;
+	kref_put(&peer->refcount, kref_release);
+}
+
+int __init wg_peer_init(void)
+{
+	peer_cache = KMEM_CACHE(wg_peer, 0);
+	return peer_cache ? 0 : -ENOMEM;
+}
+
+void wg_peer_uninit(void)
+{
+	kmem_cache_destroy(peer_cache);
+}

linux-7.2.3/drivers/net/wireguard/peer.h

@@ -0,0 +1,86 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#ifndef _WG_PEER_H
+#define _WG_PEER_H
+
+#include "device.h"
+#include "noise.h"
+#include "cookie.h"
+
+#include <linux/types.h>
+#include <linux/netfilter.h>
+#include <linux/spinlock.h>
+#include <linux/kref.h>
+#include <net/dst_cache.h>
+
+struct wg_device;
+
+struct endpoint {
+	union {
+		struct sockaddr_inet addr;     /* Large enough for both address families */
+		struct sockaddr_in addr4;
+		struct sockaddr_in6 addr6;
+	};
+	union {
+		struct {
+			struct in_addr src4;
+			/* Essentially the same as addr6->scope_id */
+			int src_if4;
+		};
+		struct in6_addr src6;
+	};
+};
+
+struct wg_peer {
+	struct wg_device *device;
+	struct prev_queue tx_queue, rx_queue;
+	struct sk_buff_head staged_packet_queue;
+	int serial_work_cpu;
+	bool is_dead;
+	struct noise_keypairs keypairs;
+	struct endpoint endpoint;
+	struct dst_cache endpoint_cache;
+	rwlock_t endpoint_lock;
+	struct noise_handshake handshake;
+	atomic64_t last_sent_handshake;
+	struct work_struct transmit_handshake_work, clear_peer_work, transmit_packet_work;
+	struct cookie latest_cookie;
+	struct hlist_node pubkey_hash;
+	u64 rx_bytes, tx_bytes;
+	struct timer_list timer_retransmit_handshake, timer_send_keepalive;
+	struct timer_list timer_new_handshake, timer_zero_key_material;
+	struct timer_list timer_persistent_keepalive;
+	unsigned int timer_handshake_attempts;
+	u16 persistent_keepalive_interval;
+	bool timer_need_another_keepalive;
+	bool sent_lastminute_handshake;
+	struct timespec64 walltime_last_handshake;
+	struct kref refcount;
+	struct rcu_head rcu;
+	struct list_head peer_list;
+	struct list_head allowedips_list;
+	struct napi_struct napi;
+	u64 internal_id;
+};
+
+struct wg_peer *wg_peer_create(struct wg_device *wg,
+			       const u8 public_key[NOISE_PUBLIC_KEY_LEN],
+			       const u8 preshared_key[NOISE_SYMMETRIC_KEY_LEN]);
+
+struct wg_peer *__must_check wg_peer_get_maybe_zero(struct wg_peer *peer);
+static inline struct wg_peer *wg_peer_get(struct wg_peer *peer)
+{
+	kref_get(&peer->refcount);
+	return peer;
+}
+void wg_peer_put(struct wg_peer *peer);
+void wg_peer_remove(struct wg_peer *peer);
+void wg_peer_remove_all(struct wg_device *wg);
+
+int wg_peer_init(void);
+void wg_peer_uninit(void);
+
+#endif /* _WG_PEER_H */

linux-7.2.3/drivers/net/wireguard/peerlookup.c

@@ -0,0 +1,226 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include "peerlookup.h"
+#include "peer.h"
+#include "noise.h"
+
+static struct hlist_head *pubkey_bucket(struct pubkey_hashtable *table,
+					const u8 pubkey[NOISE_PUBLIC_KEY_LEN])
+{
+	/* siphash gives us a secure 64bit number based on a random key. Since
+	 * the bits are uniformly distributed, we can then mask off to get the
+	 * bits we need.
+	 */
+	const u64 hash = siphash(pubkey, NOISE_PUBLIC_KEY_LEN, &table->key);
+
+	return &table->hashtable[hash & (HASH_SIZE(table->hashtable) - 1)];
+}
+
+struct pubkey_hashtable *wg_pubkey_hashtable_alloc(void)
+{
+	struct pubkey_hashtable *table = kvmalloc_obj(*table);
+
+	if (!table)
+		return NULL;
+
+	get_random_bytes(&table->key, sizeof(table->key));
+	hash_init(table->hashtable);
+	mutex_init(&table->lock);
+	return table;
+}
+
+void wg_pubkey_hashtable_add(struct pubkey_hashtable *table,
+			     struct wg_peer *peer)
+{
+	mutex_lock(&table->lock);
+	hlist_add_head_rcu(&peer->pubkey_hash,
+			   pubkey_bucket(table, peer->handshake.remote_static));
+	mutex_unlock(&table->lock);
+}
+
+void wg_pubkey_hashtable_remove(struct pubkey_hashtable *table,
+				struct wg_peer *peer)
+{
+	mutex_lock(&table->lock);
+	hlist_del_init_rcu(&peer->pubkey_hash);
+	mutex_unlock(&table->lock);
+}
+
+/* Returns a strong reference to a peer */
+struct wg_peer *
+wg_pubkey_hashtable_lookup(struct pubkey_hashtable *table,
+			   const u8 pubkey[NOISE_PUBLIC_KEY_LEN])
+{
+	struct wg_peer *iter_peer, *peer = NULL;
+
+	rcu_read_lock_bh();
+	hlist_for_each_entry_rcu_bh(iter_peer, pubkey_bucket(table, pubkey),
+				    pubkey_hash) {
+		if (!memcmp(pubkey, iter_peer->handshake.remote_static,
+			    NOISE_PUBLIC_KEY_LEN)) {
+			peer = iter_peer;
+			break;
+		}
+	}
+	peer = wg_peer_get_maybe_zero(peer);
+	rcu_read_unlock_bh();
+	return peer;
+}
+
+static struct hlist_head *index_bucket(struct index_hashtable *table,
+				       const __le32 index)
+{
+	/* Since the indices are random and thus all bits are uniformly
+	 * distributed, we can find its bucket simply by masking.
+	 */
+	return &table->hashtable[(__force u32)index &
+				 (HASH_SIZE(table->hashtable) - 1)];
+}
+
+struct index_hashtable *wg_index_hashtable_alloc(void)
+{
+	struct index_hashtable *table = kvmalloc_obj(*table);
+
+	if (!table)
+		return NULL;
+
+	hash_init(table->hashtable);
+	spin_lock_init(&table->lock);
+	return table;
+}
+
+/* At the moment, we limit ourselves to 2^20 total peers, which generally might
+ * amount to 2^20*3 items in this hashtable. The algorithm below works by
+ * picking a random number and testing it. We can see that these limits mean we
+ * usually succeed pretty quickly:
+ *
+ * >>> def calculation(tries, size):
+ * ...     return (size / 2**32)**(tries - 1) *  (1 - (size / 2**32))
+ * ...
+ * >>> calculation(1, 2**20 * 3)
+ * 0.999267578125
+ * >>> calculation(2, 2**20 * 3)
+ * 0.0007318854331970215
+ * >>> calculation(3, 2**20 * 3)
+ * 5.360489012673497e-07
+ * >>> calculation(4, 2**20 * 3)
+ * 3.9261394135792216e-10
+ *
+ * At the moment, we don't do any masking, so this algorithm isn't exactly
+ * constant time in either the random guessing or in the hash list lookup. We
+ * could require a minimum of 3 tries, which would successfully mask the
+ * guessing. this would not, however, help with the growing hash lengths, which
+ * is another thing to consider moving forward.
+ */
+
+__le32 wg_index_hashtable_insert(struct index_hashtable *table,
+				 struct index_hashtable_entry *entry)
+{
+	struct index_hashtable_entry *existing_entry;
+
+	spin_lock_bh(&table->lock);
+	hlist_del_init_rcu(&entry->index_hash);
+	spin_unlock_bh(&table->lock);
+
+	rcu_read_lock_bh();
+
+search_unused_slot:
+	/* First we try to find an unused slot, randomly, while unlocked. */
+	entry->index = (__force __le32)get_random_u32();
+	hlist_for_each_entry_rcu_bh(existing_entry,
+				    index_bucket(table, entry->index),
+				    index_hash) {
+		if (existing_entry->index == entry->index)
+			/* If it's already in use, we continue searching. */
+			goto search_unused_slot;
+	}
+
+	/* Once we've found an unused slot, we lock it, and then double-check
+	 * that nobody else stole it from us.
+	 */
+	spin_lock_bh(&table->lock);
+	hlist_for_each_entry_rcu_bh(existing_entry,
+				    index_bucket(table, entry->index),
+				    index_hash) {
+		if (existing_entry->index == entry->index) {
+			spin_unlock_bh(&table->lock);
+			/* If it was stolen, we start over. */
+			goto search_unused_slot;
+		}
+	}
+	/* Otherwise, we know we have it exclusively (since we're locked),
+	 * so we insert.
+	 */
+	hlist_add_head_rcu(&entry->index_hash,
+			   index_bucket(table, entry->index));
+	spin_unlock_bh(&table->lock);
+
+	rcu_read_unlock_bh();
+
+	return entry->index;
+}
+
+bool wg_index_hashtable_replace(struct index_hashtable *table,
+				struct index_hashtable_entry *old,
+				struct index_hashtable_entry *new)
+{
+	bool ret;
+
+	spin_lock_bh(&table->lock);
+	ret = !hlist_unhashed(&old->index_hash);
+	if (unlikely(!ret))
+		goto out;
+
+	new->index = old->index;
+	hlist_replace_rcu(&old->index_hash, &new->index_hash);
+
+	/* Calling init here NULLs out index_hash, and in fact after this
+	 * function returns, it's theoretically possible for this to get
+	 * reinserted elsewhere. That means the RCU lookup below might either
+	 * terminate early or jump between buckets, in which case the packet
+	 * simply gets dropped, which isn't terrible.
+	 */
+	INIT_HLIST_NODE(&old->index_hash);
+out:
+	spin_unlock_bh(&table->lock);
+	return ret;
+}
+
+void wg_index_hashtable_remove(struct index_hashtable *table,
+			       struct index_hashtable_entry *entry)
+{
+	spin_lock_bh(&table->lock);
+	hlist_del_init_rcu(&entry->index_hash);
+	spin_unlock_bh(&table->lock);
+}
+
+/* Returns a strong reference to a entry->peer */
+struct index_hashtable_entry *
+wg_index_hashtable_lookup(struct index_hashtable *table,
+			  const enum index_hashtable_type type_mask,
+			  const __le32 index, struct wg_peer **peer)
+{
+	struct index_hashtable_entry *iter_entry, *entry = NULL;
+
+	rcu_read_lock_bh();
+	hlist_for_each_entry_rcu_bh(iter_entry, index_bucket(table, index),
+				    index_hash) {
+		if (iter_entry->index == index) {
+			if (likely(iter_entry->type & type_mask))
+				entry = iter_entry;
+			break;
+		}
+	}
+	if (likely(entry)) {
+		entry->peer = wg_peer_get_maybe_zero(entry->peer);
+		if (likely(entry->peer))
+			*peer = entry->peer;
+		else
+			entry = NULL;
+	}
+	rcu_read_unlock_bh();
+	return entry;
+}

linux-7.2.3/drivers/net/wireguard/peerlookup.h

@@ -0,0 +1,64 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#ifndef _WG_PEERLOOKUP_H
+#define _WG_PEERLOOKUP_H
+
+#include "messages.h"
+
+#include <linux/hashtable.h>
+#include <linux/mutex.h>
+#include <linux/siphash.h>
+
+struct wg_peer;
+
+struct pubkey_hashtable {
+	/* TODO: move to rhashtable */
+	DECLARE_HASHTABLE(hashtable, 11);
+	siphash_key_t key;
+	struct mutex lock;
+};
+
+struct pubkey_hashtable *wg_pubkey_hashtable_alloc(void);
+void wg_pubkey_hashtable_add(struct pubkey_hashtable *table,
+			     struct wg_peer *peer);
+void wg_pubkey_hashtable_remove(struct pubkey_hashtable *table,
+				struct wg_peer *peer);
+struct wg_peer *
+wg_pubkey_hashtable_lookup(struct pubkey_hashtable *table,
+			   const u8 pubkey[NOISE_PUBLIC_KEY_LEN]);
+
+struct index_hashtable {
+	/* TODO: move to rhashtable */
+	DECLARE_HASHTABLE(hashtable, 13);
+	spinlock_t lock;
+};
+
+enum index_hashtable_type {
+	INDEX_HASHTABLE_HANDSHAKE = 1U << 0,
+	INDEX_HASHTABLE_KEYPAIR = 1U << 1
+};
+
+struct index_hashtable_entry {
+	struct wg_peer *peer;
+	struct hlist_node index_hash;
+	enum index_hashtable_type type;
+	__le32 index;
+};
+
+struct index_hashtable *wg_index_hashtable_alloc(void);
+__le32 wg_index_hashtable_insert(struct index_hashtable *table,
+				 struct index_hashtable_entry *entry);
+bool wg_index_hashtable_replace(struct index_hashtable *table,
+				struct index_hashtable_entry *old,
+				struct index_hashtable_entry *new);
+void wg_index_hashtable_remove(struct index_hashtable *table,
+			       struct index_hashtable_entry *entry);
+struct index_hashtable_entry *
+wg_index_hashtable_lookup(struct index_hashtable *table,
+			  const enum index_hashtable_type type_mask,
+			  const __le32 index, struct wg_peer **peer);
+
+#endif /* _WG_PEERLOOKUP_H */

linux-7.2.3/drivers/net/wireguard/queueing.c

@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include "queueing.h"
+#include <linux/skb_array.h>
+
+struct multicore_worker __percpu *
+wg_packet_percpu_multicore_worker_alloc(work_func_t function, void *ptr)
+{
+	int cpu;
+	struct multicore_worker __percpu *worker = alloc_percpu(struct multicore_worker);
+
+	if (!worker)
+		return NULL;
+
+	for_each_possible_cpu(cpu) {
+		per_cpu_ptr(worker, cpu)->ptr = ptr;
+		INIT_WORK(&per_cpu_ptr(worker, cpu)->work, function);
+	}
+	return worker;
+}
+
+int wg_packet_queue_init(struct crypt_queue *queue, work_func_t function,
+			 unsigned int len)
+{
+	int ret;
+
+	memset(queue, 0, sizeof(*queue));
+	queue->last_cpu = -1;
+	ret = ptr_ring_init(&queue->ring, len, GFP_KERNEL);
+	if (ret)
+		return ret;
+	queue->worker = wg_packet_percpu_multicore_worker_alloc(function, queue);
+	if (!queue->worker) {
+		ptr_ring_cleanup(&queue->ring, NULL);
+		return -ENOMEM;
+	}
+	return 0;
+}
+
+void wg_packet_queue_free(struct crypt_queue *queue, bool purge)
+{
+	free_percpu(queue->worker);
+	WARN_ON(!purge && !__ptr_ring_empty(&queue->ring));
+	ptr_ring_cleanup(&queue->ring, purge ? __skb_array_destroy_skb : NULL);
+}
+
+#define NEXT(skb) ((skb)->prev)
+#define STUB(queue) ((struct sk_buff *)&queue->empty)
+
+void wg_prev_queue_init(struct prev_queue *queue)
+{
+	NEXT(STUB(queue)) = NULL;
+	queue->head = queue->tail = STUB(queue);
+	queue->peeked = NULL;
+	atomic_set(&queue->count, 0);
+	BUILD_BUG_ON(
+		offsetof(struct sk_buff, next) != offsetof(struct prev_queue, empty.next) -
+							offsetof(struct prev_queue, empty) ||
+		offsetof(struct sk_buff, prev) != offsetof(struct prev_queue, empty.prev) -
+							 offsetof(struct prev_queue, empty));
+}
+
+static void __wg_prev_queue_enqueue(struct prev_queue *queue, struct sk_buff *skb)
+{
+	WRITE_ONCE(NEXT(skb), NULL);
+	WRITE_ONCE(NEXT(xchg_release(&queue->head, skb)), skb);
+}
+
+bool wg_prev_queue_enqueue(struct prev_queue *queue, struct sk_buff *skb)
+{
+	if (!atomic_add_unless(&queue->count, 1, MAX_QUEUED_PACKETS))
+		return false;
+	__wg_prev_queue_enqueue(queue, skb);
+	return true;
+}
+
+struct sk_buff *wg_prev_queue_dequeue(struct prev_queue *queue)
+{
+	struct sk_buff *tail = queue->tail, *next = smp_load_acquire(&NEXT(tail));
+
+	if (tail == STUB(queue)) {
+		if (!next)
+			return NULL;
+		queue->tail = next;
+		tail = next;
+		next = smp_load_acquire(&NEXT(next));
+	}
+	if (next) {
+		queue->tail = next;
+		atomic_dec(&queue->count);
+		return tail;
+	}
+	if (tail != READ_ONCE(queue->head))
+		return NULL;
+	__wg_prev_queue_enqueue(queue, STUB(queue));
+	next = smp_load_acquire(&NEXT(tail));
+	if (next) {
+		queue->tail = next;
+		atomic_dec(&queue->count);
+		return tail;
+	}
+	return NULL;
+}
+
+#undef NEXT
+#undef STUB

linux-7.2.3/drivers/net/wireguard/queueing.h

@@ -0,0 +1,204 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#ifndef _WG_QUEUEING_H
+#define _WG_QUEUEING_H
+
+#include "peer.h"
+#include <linux/types.h>
+#include <linux/skbuff.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <net/ip_tunnels.h>
+
+struct wg_device;
+struct wg_peer;
+struct multicore_worker;
+struct crypt_queue;
+struct prev_queue;
+struct sk_buff;
+
+/* queueing.c APIs: */
+int wg_packet_queue_init(struct crypt_queue *queue, work_func_t function,
+			 unsigned int len);
+void wg_packet_queue_free(struct crypt_queue *queue, bool purge);
+struct multicore_worker __percpu *
+wg_packet_percpu_multicore_worker_alloc(work_func_t function, void *ptr);
+
+/* receive.c APIs: */
+void wg_packet_receive(struct wg_device *wg, struct sk_buff *skb);
+void wg_packet_handshake_receive_worker(struct work_struct *work);
+/* NAPI poll function: */
+int wg_packet_rx_poll(struct napi_struct *napi, int budget);
+/* Workqueue worker: */
+void wg_packet_decrypt_worker(struct work_struct *work);
+
+/* send.c APIs: */
+void wg_packet_send_queued_handshake_initiation(struct wg_peer *peer,
+						bool is_retry);
+void wg_packet_send_handshake_response(struct wg_peer *peer);
+void wg_packet_send_handshake_cookie(struct wg_device *wg,
+				     struct sk_buff *initiating_skb,
+				     __le32 sender_index);
+void wg_packet_send_keepalive(struct wg_peer *peer);
+void wg_packet_purge_staged_packets(struct wg_peer *peer);
+void wg_packet_send_staged_packets(struct wg_peer *peer);
+/* Workqueue workers: */
+void wg_packet_handshake_send_worker(struct work_struct *work);
+void wg_packet_tx_worker(struct work_struct *work);
+void wg_packet_encrypt_worker(struct work_struct *work);
+
+enum packet_state {
+	PACKET_STATE_UNCRYPTED,
+	PACKET_STATE_CRYPTED,
+	PACKET_STATE_DEAD
+};
+
+struct packet_cb {
+	u64 nonce;
+	struct noise_keypair *keypair;
+	atomic_t state;
+	u32 mtu;
+	u8 ds;
+};
+
+#define PACKET_CB(skb) ((struct packet_cb *)((skb)->cb))
+#define PACKET_PEER(skb) (PACKET_CB(skb)->keypair->entry.peer)
+
+static inline bool wg_check_packet_protocol(struct sk_buff *skb)
+{
+	__be16 real_protocol = ip_tunnel_parse_protocol(skb);
+	return real_protocol && skb->protocol == real_protocol;
+}
+
+static inline void wg_reset_packet(struct sk_buff *skb, bool encapsulating)
+{
+	u8 l4_hash = skb->l4_hash;
+	u8 sw_hash = skb->sw_hash;
+	u32 hash = skb->hash;
+	skb_scrub_packet(skb, true);
+	memset(&skb->headers, 0, sizeof(skb->headers));
+	if (encapsulating) {
+		skb->l4_hash = l4_hash;
+		skb->sw_hash = sw_hash;
+		skb->hash = hash;
+	}
+	skb->queue_mapping = 0;
+	skb->nohdr = 0;
+	skb->peeked = 0;
+	skb->mac_len = 0;
+	skb->dev = NULL;
+#ifdef CONFIG_NET_SCHED
+	skb->tc_index = 0;
+#endif
+	skb_reset_redirect(skb);
+	skb->hdr_len = skb_headroom(skb);
+	skb_reset_mac_header(skb);
+	skb_reset_network_header(skb);
+	skb_reset_transport_header(skb);
+	skb_probe_transport_header(skb);
+	skb_reset_inner_headers(skb);
+}
+
+static inline int wg_cpumask_choose_online(int *stored_cpu, unsigned int id)
+{
+	unsigned int cpu = *stored_cpu;
+
+	while (unlikely(cpu >= nr_cpu_ids || !cpu_online(cpu)))
+		cpu = *stored_cpu = cpumask_nth(id % num_online_cpus(), cpu_online_mask);
+
+	return cpu;
+}
+
+/* This function is racy, in the sense that it's called while last_cpu is
+ * unlocked, so it could return the same CPU twice. Adding locking or using
+ * atomic sequence numbers is slower though, and the consequences of racing are
+ * harmless, so live with it.
+ */
+static inline int wg_cpumask_next_online(int *last_cpu)
+{
+	int cpu = cpumask_next(READ_ONCE(*last_cpu), cpu_online_mask);
+	if (cpu >= nr_cpu_ids)
+		cpu = cpumask_first(cpu_online_mask);
+	WRITE_ONCE(*last_cpu, cpu);
+	return cpu;
+}
+
+void wg_prev_queue_init(struct prev_queue *queue);
+
+/* Multi producer */
+bool wg_prev_queue_enqueue(struct prev_queue *queue, struct sk_buff *skb);
+
+/* Single consumer */
+struct sk_buff *wg_prev_queue_dequeue(struct prev_queue *queue);
+
+/* Single consumer */
+static inline struct sk_buff *wg_prev_queue_peek(struct prev_queue *queue)
+{
+	if (queue->peeked)
+		return queue->peeked;
+	queue->peeked = wg_prev_queue_dequeue(queue);
+	return queue->peeked;
+}
+
+/* Single consumer */
+static inline void wg_prev_queue_drop_peeked(struct prev_queue *queue)
+{
+	queue->peeked = NULL;
+}
+
+static inline int wg_queue_enqueue_per_device_and_peer(
+	struct crypt_queue *device_queue, struct prev_queue *peer_queue,
+	struct sk_buff *skb, struct workqueue_struct *wq)
+{
+	int cpu;
+
+	atomic_set_release(&PACKET_CB(skb)->state, PACKET_STATE_UNCRYPTED);
+	/* We first queue this up for the peer ingestion, but the consumer
+	 * will wait for the state to change to CRYPTED or DEAD before.
+	 */
+	if (unlikely(!wg_prev_queue_enqueue(peer_queue, skb)))
+		return -ENOSPC;
+
+	/* Then we queue it up in the device queue, which consumes the
+	 * packet as soon as it can.
+	 */
+	cpu = wg_cpumask_next_online(&device_queue->last_cpu);
+	if (unlikely(ptr_ring_produce_bh(&device_queue->ring, skb)))
+		return -EPIPE;
+	queue_work_on(cpu, wq, &per_cpu_ptr(device_queue->worker, cpu)->work);
+	return 0;
+}
+
+static inline void wg_queue_enqueue_per_peer_tx(struct sk_buff *skb, enum packet_state state)
+{
+	/* We take a reference, because as soon as we call atomic_set, the
+	 * peer can be freed from below us.
+	 */
+	struct wg_peer *peer = wg_peer_get(PACKET_PEER(skb));
+
+	atomic_set_release(&PACKET_CB(skb)->state, state);
+	queue_work_on(wg_cpumask_choose_online(&peer->serial_work_cpu, peer->internal_id),
+		      peer->device->packet_crypt_wq, &peer->transmit_packet_work);
+	wg_peer_put(peer);
+}
+
+static inline void wg_queue_enqueue_per_peer_rx(struct sk_buff *skb, enum packet_state state)
+{
+	/* We take a reference, because as soon as we call atomic_set, the
+	 * peer can be freed from below us.
+	 */
+	struct wg_peer *peer = wg_peer_get(PACKET_PEER(skb));
+
+	atomic_set_release(&PACKET_CB(skb)->state, state);
+	napi_schedule(&peer->napi);
+	wg_peer_put(peer);
+}
+
+#ifdef DEBUG
+bool wg_packet_counter_selftest(void);
+#endif
+
+#endif /* _WG_QUEUEING_H */

linux-7.2.3/drivers/net/wireguard/ratelimiter.c

@@ -0,0 +1,223 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include "ratelimiter.h"
+#include <linux/siphash.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <net/ip.h>
+
+static struct kmem_cache *entry_cache;
+static hsiphash_key_t key;
+static spinlock_t table_lock = __SPIN_LOCK_UNLOCKED("ratelimiter_table_lock");
+static DEFINE_MUTEX(init_lock);
+static u64 init_refcnt; /* Protected by init_lock, hence not atomic. */
+static atomic_t total_entries = ATOMIC_INIT(0);
+static unsigned int max_entries, table_size;
+static void wg_ratelimiter_gc_entries(struct work_struct *);
+static DECLARE_DEFERRABLE_WORK(gc_work, wg_ratelimiter_gc_entries);
+static struct hlist_head *table_v4;
+#if IS_ENABLED(CONFIG_IPV6)
+static struct hlist_head *table_v6;
+#endif
+
+struct ratelimiter_entry {
+	u64 last_time_ns, tokens, ip;
+	void *net;
+	spinlock_t lock;
+	struct hlist_node hash;
+	struct rcu_head rcu;
+};
+
+enum {
+	PACKETS_PER_SECOND = 20,
+	PACKETS_BURSTABLE = 5,
+	PACKET_COST = NSEC_PER_SEC / PACKETS_PER_SECOND,
+	TOKEN_MAX = PACKET_COST * PACKETS_BURSTABLE
+};
+
+static void entry_free(struct rcu_head *rcu)
+{
+	kmem_cache_free(entry_cache,
+			container_of(rcu, struct ratelimiter_entry, rcu));
+	atomic_dec(&total_entries);
+}
+
+static void entry_uninit(struct ratelimiter_entry *entry)
+{
+	hlist_del_rcu(&entry->hash);
+	call_rcu(&entry->rcu, entry_free);
+}
+
+/* Calling this function with a NULL work uninits all entries. */
+static void wg_ratelimiter_gc_entries(struct work_struct *work)
+{
+	const u64 now = ktime_get_coarse_boottime_ns();
+	struct ratelimiter_entry *entry;
+	struct hlist_node *temp;
+	unsigned int i;
+
+	for (i = 0; i < table_size; ++i) {
+		spin_lock(&table_lock);
+		hlist_for_each_entry_safe(entry, temp, &table_v4[i], hash) {
+			if (unlikely(!work) ||
+			    now - entry->last_time_ns > NSEC_PER_SEC)
+				entry_uninit(entry);
+		}
+#if IS_ENABLED(CONFIG_IPV6)
+		hlist_for_each_entry_safe(entry, temp, &table_v6[i], hash) {
+			if (unlikely(!work) ||
+			    now - entry->last_time_ns > NSEC_PER_SEC)
+				entry_uninit(entry);
+		}
+#endif
+		spin_unlock(&table_lock);
+		if (likely(work))
+			cond_resched();
+	}
+	if (likely(work))
+		queue_delayed_work(system_power_efficient_wq, &gc_work, HZ);
+}
+
+bool wg_ratelimiter_allow(struct sk_buff *skb, struct net *net)
+{
+	/* We only take the bottom half of the net pointer, so that we can hash
+	 * 3 words in the end. This way, siphash's len param fits into the final
+	 * u32, and we don't incur an extra round.
+	 */
+	const u32 net_word = (unsigned long)net;
+	struct ratelimiter_entry *entry;
+	struct hlist_head *bucket;
+	u64 ip;
+
+	if (skb->protocol == htons(ETH_P_IP)) {
+		ip = (u64 __force)ip_hdr(skb)->saddr;
+		bucket = &table_v4[hsiphash_2u32(net_word, ip, &key) &
+				   (table_size - 1)];
+	}
+#if IS_ENABLED(CONFIG_IPV6)
+	else if (skb->protocol == htons(ETH_P_IPV6)) {
+		/* Only use 64 bits, so as to ratelimit the whole /64. */
+		memcpy(&ip, &ipv6_hdr(skb)->saddr, sizeof(ip));
+		bucket = &table_v6[hsiphash_3u32(net_word, ip >> 32, ip, &key) &
+				   (table_size - 1)];
+	}
+#endif
+	else
+		return false;
+	rcu_read_lock();
+	hlist_for_each_entry_rcu(entry, bucket, hash) {
+		if (entry->net == net && entry->ip == ip) {
+			u64 now, tokens;
+			bool ret;
+			/* Quasi-inspired by nft_limit.c, but this is actually a
+			 * slightly different algorithm. Namely, we incorporate
+			 * the burst as part of the maximum tokens, rather than
+			 * as part of the rate.
+			 */
+			spin_lock(&entry->lock);
+			now = ktime_get_coarse_boottime_ns();
+			tokens = min_t(u64, TOKEN_MAX,
+				       entry->tokens + now -
+					       entry->last_time_ns);
+			entry->last_time_ns = now;
+			ret = tokens >= PACKET_COST;
+			entry->tokens = ret ? tokens - PACKET_COST : tokens;
+			spin_unlock(&entry->lock);
+			rcu_read_unlock();
+			return ret;
+		}
+	}
+	rcu_read_unlock();
+
+	if (atomic_inc_return(&total_entries) > max_entries)
+		goto err_oom;
+
+	entry = kmem_cache_alloc(entry_cache, GFP_KERNEL);
+	if (unlikely(!entry))
+		goto err_oom;
+
+	entry->net = net;
+	entry->ip = ip;
+	INIT_HLIST_NODE(&entry->hash);
+	spin_lock_init(&entry->lock);
+	entry->last_time_ns = ktime_get_coarse_boottime_ns();
+	entry->tokens = TOKEN_MAX - PACKET_COST;
+	spin_lock(&table_lock);
+	hlist_add_head_rcu(&entry->hash, bucket);
+	spin_unlock(&table_lock);
+	return true;
+
+err_oom:
+	atomic_dec(&total_entries);
+	return false;
+}
+
+int wg_ratelimiter_init(void)
+{
+	mutex_lock(&init_lock);
+	if (++init_refcnt != 1)
+		goto out;
+
+	entry_cache = KMEM_CACHE(ratelimiter_entry, 0);
+	if (!entry_cache)
+		goto err;
+
+	/* xt_hashlimit.c uses a slightly different algorithm for ratelimiting,
+	 * but what it shares in common is that it uses a massive hashtable. So,
+	 * we borrow their wisdom about good table sizes on different systems
+	 * dependent on RAM. This calculation here comes from there.
+	 */
+	table_size = (totalram_pages() > (1U << 30) / PAGE_SIZE) ? 8192 :
+		max_t(unsigned long, 16, roundup_pow_of_two(
+			(totalram_pages() << PAGE_SHIFT) /
+			(1U << 14) / sizeof(struct hlist_head)));
+	max_entries = table_size * 8;
+
+	table_v4 = kvzalloc_objs(*table_v4, table_size);
+	if (unlikely(!table_v4))
+		goto err_kmemcache;
+
+#if IS_ENABLED(CONFIG_IPV6)
+	table_v6 = kvzalloc_objs(*table_v6, table_size);
+	if (unlikely(!table_v6)) {
+		kvfree(table_v4);
+		goto err_kmemcache;
+	}
+#endif
+
+	queue_delayed_work(system_power_efficient_wq, &gc_work, HZ);
+	get_random_bytes(&key, sizeof(key));
+out:
+	mutex_unlock(&init_lock);
+	return 0;
+
+err_kmemcache:
+	kmem_cache_destroy(entry_cache);
+err:
+	--init_refcnt;
+	mutex_unlock(&init_lock);
+	return -ENOMEM;
+}
+
+void wg_ratelimiter_uninit(void)
+{
+	mutex_lock(&init_lock);
+	if (!init_refcnt || --init_refcnt)
+		goto out;
+
+	cancel_delayed_work_sync(&gc_work);
+	wg_ratelimiter_gc_entries(NULL);
+	rcu_barrier();
+	kvfree(table_v4);
+#if IS_ENABLED(CONFIG_IPV6)
+	kvfree(table_v6);
+#endif
+	kmem_cache_destroy(entry_cache);
+out:
+	mutex_unlock(&init_lock);
+}
+
+#include "selftest/ratelimiter.c"

linux-7.2.3/drivers/net/wireguard/ratelimiter.h

@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#ifndef _WG_RATELIMITER_H
+#define _WG_RATELIMITER_H
+
+#include <linux/skbuff.h>
+
+int wg_ratelimiter_init(void);
+void wg_ratelimiter_uninit(void);
+bool wg_ratelimiter_allow(struct sk_buff *skb, struct net *net);
+
+#ifdef DEBUG
+bool wg_ratelimiter_selftest(void);
+#endif
+
+#endif /* _WG_RATELIMITER_H */

linux-7.2.3/drivers/net/wireguard/receive.c

@@ -0,0 +1,586 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include "queueing.h"
+#include "device.h"
+#include "peer.h"
+#include "timers.h"
+#include "messages.h"
+#include "cookie.h"
+#include "socket.h"
+
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/udp.h>
+#include <net/ip_tunnels.h>
+
+/* Must be called with bh disabled. */
+static void update_rx_stats(struct wg_peer *peer, size_t len)
+{
+	dev_sw_netstats_rx_add(peer->device->dev, len);
+	peer->rx_bytes += len;
+}
+
+#define SKB_TYPE_LE32(skb) (((struct message_header *)(skb)->data)->type)
+
+static size_t validate_header_len(struct sk_buff *skb)
+{
+	if (unlikely(skb->len < sizeof(struct message_header)))
+		return 0;
+	if (SKB_TYPE_LE32(skb) == cpu_to_le32(MESSAGE_DATA) &&
+	    skb->len >= MESSAGE_MINIMUM_LENGTH)
+		return sizeof(struct message_data);
+	if (SKB_TYPE_LE32(skb) == cpu_to_le32(MESSAGE_HANDSHAKE_INITIATION) &&
+	    skb->len == sizeof(struct message_handshake_initiation))
+		return sizeof(struct message_handshake_initiation);
+	if (SKB_TYPE_LE32(skb) == cpu_to_le32(MESSAGE_HANDSHAKE_RESPONSE) &&
+	    skb->len == sizeof(struct message_handshake_response))
+		return sizeof(struct message_handshake_response);
+	if (SKB_TYPE_LE32(skb) == cpu_to_le32(MESSAGE_HANDSHAKE_COOKIE) &&
+	    skb->len == sizeof(struct message_handshake_cookie))
+		return sizeof(struct message_handshake_cookie);
+	return 0;
+}
+
+static int prepare_skb_header(struct sk_buff *skb, struct wg_device *wg)
+{
+	size_t data_offset, data_len, header_len;
+	struct udphdr *udp;
+
+	if (unlikely(!wg_check_packet_protocol(skb) ||
+		     skb_transport_header(skb) < skb->head ||
+		     (skb_transport_header(skb) + sizeof(struct udphdr)) >
+			     skb_tail_pointer(skb)))
+		return -EINVAL; /* Bogus IP header */
+	udp = udp_hdr(skb);
+	data_offset = (u8 *)udp - skb->data;
+	if (unlikely(data_offset > U16_MAX ||
+		     data_offset + sizeof(struct udphdr) > skb->len))
+		/* Packet has offset at impossible location or isn't big enough
+		 * to have UDP fields.
+		 */
+		return -EINVAL;
+	data_len = ntohs(udp->len);
+	if (unlikely(data_len < sizeof(struct udphdr) ||
+		     data_len > skb->len - data_offset))
+		/* UDP packet is reporting too small of a size or lying about
+		 * its size.
+		 */
+		return -EINVAL;
+	data_len -= sizeof(struct udphdr);
+	data_offset = (u8 *)udp + sizeof(struct udphdr) - skb->data;
+	if (unlikely(!pskb_may_pull(skb,
+				data_offset + sizeof(struct message_header)) ||
+		     pskb_trim(skb, data_len + data_offset) < 0))
+		return -EINVAL;
+	skb_pull(skb, data_offset);
+	if (unlikely(skb->len != data_len))
+		/* Final len does not agree with calculated len */
+		return -EINVAL;
+	header_len = validate_header_len(skb);
+	if (unlikely(!header_len))
+		return -EINVAL;
+	__skb_push(skb, data_offset);
+	if (unlikely(!pskb_may_pull(skb, data_offset + header_len)))
+		return -EINVAL;
+	__skb_pull(skb, data_offset);
+	return 0;
+}
+
+static void wg_receive_handshake_packet(struct wg_device *wg,
+					struct sk_buff *skb)
+{
+	enum cookie_mac_state mac_state;
+	struct wg_peer *peer = NULL;
+	/* This is global, so that our load calculation applies to the whole
+	 * system. We don't care about races with it at all.
+	 */
+	static u64 last_under_load;
+	bool packet_needs_cookie;
+	bool under_load;
+
+	if (SKB_TYPE_LE32(skb) == cpu_to_le32(MESSAGE_HANDSHAKE_COOKIE)) {
+		net_dbg_skb_ratelimited("%s: Receiving cookie response from %pISpfsc\n",
+					wg->dev->name, skb);
+		wg_cookie_message_consume(
+			(struct message_handshake_cookie *)skb->data, wg);
+		return;
+	}
+
+	under_load = atomic_read(&wg->handshake_queue_len) >=
+			MAX_QUEUED_INCOMING_HANDSHAKES / 8;
+	if (under_load) {
+		last_under_load = ktime_get_coarse_boottime_ns();
+	} else if (last_under_load) {
+		under_load = !wg_birthdate_has_expired(last_under_load, 1);
+		if (!under_load)
+			last_under_load = 0;
+	}
+	mac_state = wg_cookie_validate_packet(&wg->cookie_checker, skb,
+					      under_load);
+	if ((under_load && mac_state == VALID_MAC_WITH_COOKIE) ||
+	    (!under_load && mac_state == VALID_MAC_BUT_NO_COOKIE)) {
+		packet_needs_cookie = false;
+	} else if (under_load && mac_state == VALID_MAC_BUT_NO_COOKIE) {
+		packet_needs_cookie = true;
+	} else {
+		net_dbg_skb_ratelimited("%s: Invalid MAC of handshake, dropping packet from %pISpfsc\n",
+					wg->dev->name, skb);
+		return;
+	}
+
+	switch (SKB_TYPE_LE32(skb)) {
+	case cpu_to_le32(MESSAGE_HANDSHAKE_INITIATION): {
+		struct message_handshake_initiation *message =
+			(struct message_handshake_initiation *)skb->data;
+
+		if (packet_needs_cookie) {
+			wg_packet_send_handshake_cookie(wg, skb,
+							message->sender_index);
+			return;
+		}
+		peer = wg_noise_handshake_consume_initiation(message, wg);
+		if (unlikely(!peer)) {
+			net_dbg_skb_ratelimited("%s: Invalid handshake initiation from %pISpfsc\n",
+						wg->dev->name, skb);
+			return;
+		}
+		wg_socket_set_peer_endpoint_from_skb(peer, skb);
+		net_dbg_ratelimited("%s: Receiving handshake initiation from peer %llu (%pISpfsc)\n",
+				    wg->dev->name, peer->internal_id,
+				    &peer->endpoint.addr);
+		wg_packet_send_handshake_response(peer);
+		break;
+	}
+	case cpu_to_le32(MESSAGE_HANDSHAKE_RESPONSE): {
+		struct message_handshake_response *message =
+			(struct message_handshake_response *)skb->data;
+
+		if (packet_needs_cookie) {
+			wg_packet_send_handshake_cookie(wg, skb,
+							message->sender_index);
+			return;
+		}
+		peer = wg_noise_handshake_consume_response(message, wg);
+		if (unlikely(!peer)) {
+			net_dbg_skb_ratelimited("%s: Invalid handshake response from %pISpfsc\n",
+						wg->dev->name, skb);
+			return;
+		}
+		wg_socket_set_peer_endpoint_from_skb(peer, skb);
+		net_dbg_ratelimited("%s: Receiving handshake response from peer %llu (%pISpfsc)\n",
+				    wg->dev->name, peer->internal_id,
+				    &peer->endpoint.addr);
+		if (wg_noise_handshake_begin_session(&peer->handshake,
+						     &peer->keypairs)) {
+			wg_timers_session_derived(peer);
+			wg_timers_handshake_complete(peer);
+			/* Calling this function will either send any existing
+			 * packets in the queue and not send a keepalive, which
+			 * is the best case, Or, if there's nothing in the
+			 * queue, it will send a keepalive, in order to give
+			 * immediate confirmation of the session.
+			 */
+			wg_packet_send_keepalive(peer);
+		}
+		break;
+	}
+	}
+
+	if (unlikely(!peer)) {
+		WARN(1, "Somehow a wrong type of packet wound up in the handshake queue!\n");
+		return;
+	}
+
+	local_bh_disable();
+	update_rx_stats(peer, skb->len);
+	local_bh_enable();
+
+	wg_timers_any_authenticated_packet_received(peer);
+	wg_timers_any_authenticated_packet_traversal(peer);
+	wg_peer_put(peer);
+}
+
+void wg_packet_handshake_receive_worker(struct work_struct *work)
+{
+	struct crypt_queue *queue = container_of(work, struct multicore_worker, work)->ptr;
+	struct wg_device *wg = container_of(queue, struct wg_device, handshake_queue);
+	struct sk_buff *skb;
+
+	while ((skb = ptr_ring_consume_bh(&queue->ring)) != NULL) {
+		wg_receive_handshake_packet(wg, skb);
+		dev_kfree_skb(skb);
+		atomic_dec(&wg->handshake_queue_len);
+		cond_resched();
+	}
+}
+
+static void keep_key_fresh(struct wg_peer *peer)
+{
+	struct noise_keypair *keypair;
+	bool send;
+
+	if (peer->sent_lastminute_handshake)
+		return;
+
+	rcu_read_lock_bh();
+	keypair = rcu_dereference_bh(peer->keypairs.current_keypair);
+	send = keypair && READ_ONCE(keypair->sending.is_valid) &&
+	       keypair->i_am_the_initiator &&
+	       wg_birthdate_has_expired(keypair->sending.birthdate,
+			REJECT_AFTER_TIME - KEEPALIVE_TIMEOUT - REKEY_TIMEOUT);
+	rcu_read_unlock_bh();
+
+	if (unlikely(send)) {
+		peer->sent_lastminute_handshake = true;
+		wg_packet_send_queued_handshake_initiation(peer, false);
+	}
+}
+
+static bool decrypt_packet(struct sk_buff *skb, struct noise_keypair *keypair)
+{
+	struct scatterlist sg[MAX_SKB_FRAGS + 8];
+	struct sk_buff *trailer;
+	unsigned int offset;
+	int num_frags;
+
+	if (unlikely(!keypair))
+		return false;
+
+	if (unlikely(!READ_ONCE(keypair->receiving.is_valid) ||
+		  wg_birthdate_has_expired(keypair->receiving.birthdate, REJECT_AFTER_TIME) ||
+		  READ_ONCE(keypair->receiving_counter.counter) >= REJECT_AFTER_MESSAGES)) {
+		WRITE_ONCE(keypair->receiving.is_valid, false);
+		return false;
+	}
+
+	PACKET_CB(skb)->nonce =
+		le64_to_cpu(((struct message_data *)skb->data)->counter);
+
+	/* We ensure that the network header is part of the packet before we
+	 * call skb_cow_data, so that there's no chance that data is removed
+	 * from the skb, so that later we can extract the original endpoint.
+	 */
+	offset = -skb_network_offset(skb);
+	skb_push(skb, offset);
+	num_frags = skb_cow_data(skb, 0, &trailer);
+	offset += sizeof(struct message_data);
+	skb_pull(skb, offset);
+	if (unlikely(num_frags < 0 || num_frags > ARRAY_SIZE(sg)))
+		return false;
+
+	sg_init_table(sg, num_frags);
+	if (skb_to_sgvec(skb, sg, 0, skb->len) <= 0)
+		return false;
+
+	if (!chacha20poly1305_decrypt_sg_inplace(sg, skb->len, NULL, 0,
+					         PACKET_CB(skb)->nonce,
+						 keypair->receiving.key))
+		return false;
+
+	/* Another ugly situation of pushing and pulling the header so as to
+	 * keep endpoint information intact.
+	 */
+	skb_push(skb, offset);
+	if (pskb_trim(skb, skb->len - noise_encrypted_len(0)))
+		return false;
+	skb_pull(skb, offset);
+
+	return true;
+}
+
+/* This is RFC6479, a replay detection bitmap algorithm that avoids bitshifts */
+static bool counter_validate(struct noise_replay_counter *counter, u64 their_counter)
+{
+	unsigned long index, index_current, top, i;
+	bool ret = false;
+
+	spin_lock_bh(&counter->lock);
+
+	if (unlikely(counter->counter >= REJECT_AFTER_MESSAGES + 1 ||
+		     their_counter >= REJECT_AFTER_MESSAGES))
+		goto out;
+
+	++their_counter;
+
+	if (unlikely((COUNTER_WINDOW_SIZE + their_counter) <
+		     counter->counter))
+		goto out;
+
+	index = their_counter >> ilog2(BITS_PER_LONG);
+
+	if (likely(their_counter > counter->counter)) {
+		index_current = counter->counter >> ilog2(BITS_PER_LONG);
+		top = min_t(unsigned long, index - index_current,
+			    COUNTER_BITS_TOTAL / BITS_PER_LONG);
+		for (i = 1; i <= top; ++i)
+			counter->backtrack[(i + index_current) &
+				((COUNTER_BITS_TOTAL / BITS_PER_LONG) - 1)] = 0;
+		WRITE_ONCE(counter->counter, their_counter);
+	}
+
+	index &= (COUNTER_BITS_TOTAL / BITS_PER_LONG) - 1;
+	ret = !test_and_set_bit(their_counter & (BITS_PER_LONG - 1),
+				&counter->backtrack[index]);
+
+out:
+	spin_unlock_bh(&counter->lock);
+	return ret;
+}
+
+#include "selftest/counter.c"
+
+static void wg_packet_consume_data_done(struct wg_peer *peer,
+					struct sk_buff *skb,
+					struct endpoint *endpoint)
+{
+	struct net_device *dev = peer->device->dev;
+	unsigned int len, len_before_trim;
+	struct wg_peer *routed_peer;
+
+	wg_socket_set_peer_endpoint(peer, endpoint);
+
+	if (unlikely(wg_noise_received_with_keypair(&peer->keypairs,
+						    PACKET_CB(skb)->keypair))) {
+		wg_timers_handshake_complete(peer);
+		wg_packet_send_staged_packets(peer);
+	}
+
+	keep_key_fresh(peer);
+
+	wg_timers_any_authenticated_packet_received(peer);
+	wg_timers_any_authenticated_packet_traversal(peer);
+
+	/* A packet with length 0 is a keepalive packet */
+	if (unlikely(!skb->len)) {
+		update_rx_stats(peer, message_data_len(0));
+		net_dbg_ratelimited("%s: Receiving keepalive packet from peer %llu (%pISpfsc)\n",
+				    dev->name, peer->internal_id,
+				    &peer->endpoint.addr);
+		goto packet_processed;
+	}
+
+	wg_timers_data_received(peer);
+
+	if (unlikely(skb_network_header(skb) < skb->head))
+		goto dishonest_packet_size;
+	if (unlikely(!(pskb_network_may_pull(skb, sizeof(struct iphdr)) &&
+		       (ip_hdr(skb)->version == 4 ||
+			(ip_hdr(skb)->version == 6 &&
+			 pskb_network_may_pull(skb, sizeof(struct ipv6hdr)))))))
+		goto dishonest_packet_type;
+
+	skb->dev = dev;
+	/* We've already verified the Poly1305 auth tag, which means this packet
+	 * was not modified in transit. We can therefore tell the networking
+	 * stack that all checksums of every layer of encapsulation have already
+	 * been checked "by the hardware" and therefore is unnecessary to check
+	 * again in software.
+	 */
+	skb->ip_summed = CHECKSUM_UNNECESSARY;
+	skb->csum_level = ~0; /* All levels */
+	skb->protocol = ip_tunnel_parse_protocol(skb);
+	if (skb->protocol == htons(ETH_P_IP)) {
+		len = ntohs(ip_hdr(skb)->tot_len);
+		if (unlikely(len < sizeof(struct iphdr)))
+			goto dishonest_packet_size;
+		INET_ECN_decapsulate(skb, PACKET_CB(skb)->ds, ip_hdr(skb)->tos);
+	} else if (skb->protocol == htons(ETH_P_IPV6)) {
+		len = ntohs(ipv6_hdr(skb)->payload_len) +
+		      sizeof(struct ipv6hdr);
+		INET_ECN_decapsulate(skb, PACKET_CB(skb)->ds, ipv6_get_dsfield(ipv6_hdr(skb)));
+	} else {
+		goto dishonest_packet_type;
+	}
+
+	if (unlikely(len > skb->len))
+		goto dishonest_packet_size;
+	len_before_trim = skb->len;
+	if (unlikely(pskb_trim(skb, len)))
+		goto packet_processed;
+
+	routed_peer = wg_allowedips_lookup_src(&peer->device->peer_allowedips,
+					       skb);
+	wg_peer_put(routed_peer); /* We don't need the extra reference. */
+
+	if (unlikely(routed_peer != peer))
+		goto dishonest_packet_peer;
+
+	napi_gro_receive(&peer->napi, skb);
+	update_rx_stats(peer, message_data_len(len_before_trim));
+	return;
+
+dishonest_packet_peer:
+	net_dbg_skb_ratelimited("%s: Packet has unallowed src IP (%pISc) from peer %llu (%pISpfsc)\n",
+				dev->name, skb, peer->internal_id,
+				&peer->endpoint.addr);
+	DEV_STATS_INC(dev, rx_errors);
+	DEV_STATS_INC(dev, rx_frame_errors);
+	goto packet_processed;
+dishonest_packet_type:
+	net_dbg_ratelimited("%s: Packet is neither ipv4 nor ipv6 from peer %llu (%pISpfsc)\n",
+			    dev->name, peer->internal_id, &peer->endpoint.addr);
+	DEV_STATS_INC(dev, rx_errors);
+	DEV_STATS_INC(dev, rx_frame_errors);
+	goto packet_processed;
+dishonest_packet_size:
+	net_dbg_ratelimited("%s: Packet has incorrect size from peer %llu (%pISpfsc)\n",
+			    dev->name, peer->internal_id, &peer->endpoint.addr);
+	DEV_STATS_INC(dev, rx_errors);
+	DEV_STATS_INC(dev, rx_length_errors);
+	goto packet_processed;
+packet_processed:
+	dev_kfree_skb(skb);
+}
+
+int wg_packet_rx_poll(struct napi_struct *napi, int budget)
+{
+	struct wg_peer *peer = container_of(napi, struct wg_peer, napi);
+	struct noise_keypair *keypair;
+	struct endpoint endpoint;
+	enum packet_state state;
+	struct sk_buff *skb;
+	int work_done = 0;
+	bool free;
+
+	if (unlikely(budget <= 0))
+		return 0;
+
+	while ((skb = wg_prev_queue_peek(&peer->rx_queue)) != NULL &&
+	       (state = atomic_read_acquire(&PACKET_CB(skb)->state)) !=
+		       PACKET_STATE_UNCRYPTED) {
+		wg_prev_queue_drop_peeked(&peer->rx_queue);
+		keypair = PACKET_CB(skb)->keypair;
+		free = true;
+
+		if (unlikely(state != PACKET_STATE_CRYPTED))
+			goto next;
+
+		if (unlikely(!counter_validate(&keypair->receiving_counter,
+					       PACKET_CB(skb)->nonce))) {
+			net_dbg_ratelimited("%s: Packet has invalid nonce %llu (max %llu)\n",
+					    peer->device->dev->name,
+					    PACKET_CB(skb)->nonce,
+					    READ_ONCE(keypair->receiving_counter.counter));
+			goto next;
+		}
+
+		if (unlikely(wg_socket_endpoint_from_skb(&endpoint, skb)))
+			goto next;
+
+		wg_reset_packet(skb, false);
+		wg_packet_consume_data_done(peer, skb, &endpoint);
+		free = false;
+
+next:
+		wg_noise_keypair_put(keypair, false);
+		wg_peer_put(peer);
+		if (unlikely(free))
+			dev_kfree_skb(skb);
+
+		if (++work_done >= budget)
+			break;
+	}
+
+	if (work_done < budget)
+		napi_complete_done(napi, work_done);
+
+	return work_done;
+}
+
+void wg_packet_decrypt_worker(struct work_struct *work)
+{
+	struct crypt_queue *queue = container_of(work, struct multicore_worker,
+						 work)->ptr;
+	struct sk_buff *skb;
+
+	while ((skb = ptr_ring_consume_bh(&queue->ring)) != NULL) {
+		enum packet_state state =
+			likely(decrypt_packet(skb, PACKET_CB(skb)->keypair)) ?
+				PACKET_STATE_CRYPTED : PACKET_STATE_DEAD;
+		wg_queue_enqueue_per_peer_rx(skb, state);
+		if (need_resched())
+			cond_resched();
+	}
+}
+
+static void wg_packet_consume_data(struct wg_device *wg, struct sk_buff *skb)
+{
+	__le32 idx = ((struct message_data *)skb->data)->key_idx;
+	struct wg_peer *peer = NULL;
+	int ret;
+
+	rcu_read_lock_bh();
+	PACKET_CB(skb)->keypair =
+		(struct noise_keypair *)wg_index_hashtable_lookup(
+			wg->index_hashtable, INDEX_HASHTABLE_KEYPAIR, idx,
+			&peer);
+	if (unlikely(!wg_noise_keypair_get(PACKET_CB(skb)->keypair)))
+		goto err_keypair;
+
+	if (unlikely(READ_ONCE(peer->is_dead)))
+		goto err;
+
+	ret = wg_queue_enqueue_per_device_and_peer(&wg->decrypt_queue, &peer->rx_queue, skb,
+						   wg->packet_crypt_wq);
+	if (unlikely(ret == -EPIPE))
+		wg_queue_enqueue_per_peer_rx(skb, PACKET_STATE_DEAD);
+	if (likely(!ret || ret == -EPIPE)) {
+		rcu_read_unlock_bh();
+		return;
+	}
+err:
+	wg_noise_keypair_put(PACKET_CB(skb)->keypair, false);
+err_keypair:
+	rcu_read_unlock_bh();
+	wg_peer_put(peer);
+	dev_kfree_skb(skb);
+}
+
+void wg_packet_receive(struct wg_device *wg, struct sk_buff *skb)
+{
+	if (unlikely(prepare_skb_header(skb, wg) < 0))
+		goto err;
+	switch (SKB_TYPE_LE32(skb)) {
+	case cpu_to_le32(MESSAGE_HANDSHAKE_INITIATION):
+	case cpu_to_le32(MESSAGE_HANDSHAKE_RESPONSE):
+	case cpu_to_le32(MESSAGE_HANDSHAKE_COOKIE): {
+		int cpu, ret = -EBUSY;
+
+		if (unlikely(!rng_is_initialized()))
+			goto drop;
+		if (atomic_read(&wg->handshake_queue_len) > MAX_QUEUED_INCOMING_HANDSHAKES / 2) {
+			if (spin_trylock_bh(&wg->handshake_queue.ring.producer_lock)) {
+				ret = __ptr_ring_produce(&wg->handshake_queue.ring, skb);
+				spin_unlock_bh(&wg->handshake_queue.ring.producer_lock);
+			}
+		} else
+			ret = ptr_ring_produce_bh(&wg->handshake_queue.ring, skb);
+		if (ret) {
+	drop:
+			net_dbg_skb_ratelimited("%s: Dropping handshake packet from %pISpfsc\n",
+						wg->dev->name, skb);
+			goto err;
+		}
+		atomic_inc(&wg->handshake_queue_len);
+		cpu = wg_cpumask_next_online(&wg->handshake_queue.last_cpu);
+		/* Queues up a call to packet_process_queued_handshake_packets(skb): */
+		queue_work_on(cpu, wg->handshake_receive_wq,
+			      &per_cpu_ptr(wg->handshake_queue.worker, cpu)->work);
+		break;
+	}
+	case cpu_to_le32(MESSAGE_DATA):
+		PACKET_CB(skb)->ds = ip_tunnel_get_dsfield(ip_hdr(skb), skb);
+		wg_packet_consume_data(wg, skb);
+		break;
+	default:
+		WARN(1, "Non-exhaustive parsing of packet header lead to unknown packet type!\n");
+		goto err;
+	}
+	return;
+
+err:
+	dev_kfree_skb(skb);
+}

linux-7.2.3/drivers/net/wireguard/selftest/allowedips.c

@@ -0,0 +1,727 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ *
+ * This contains some basic static unit tests for the allowedips data structure.
+ * It also has two additional modes that are disabled and meant to be used by
+ * folks directly playing with this file. If you define the macro
+ * DEBUG_PRINT_TRIE_GRAPHVIZ to be 1, then every time there's a full tree in
+ * memory, it will be printed out as KERN_DEBUG in a format that can be passed
+ * to graphviz (the dot command) to visualize it. If you define the macro
+ * DEBUG_RANDOM_TRIE to be 1, then there will be an extremely costly set of
+ * randomized tests done against a trivial implementation, which may take
+ * upwards of a half-hour to complete. There's no set of users who should be
+ * enabling these, and the only developers that should go anywhere near these
+ * nobs are the ones who are reading this comment.
+ */
+
+#ifdef DEBUG
+
+#include <linux/siphash.h>
+
+static __init void print_node(struct allowedips_node *node, u8 bits)
+{
+	char *fmt_connection = KERN_DEBUG "\t\"%p/%d\" -> \"%p/%d\";\n";
+	char *fmt_declaration = KERN_DEBUG "\t\"%p/%d\"[style=%s, color=\"#%06x\"];\n";
+	u8 ip1[16], ip2[16], cidr1, cidr2;
+	char *style = "dotted";
+	u32 color = 0;
+
+	if (node == NULL)
+		return;
+	if (bits == 32) {
+		fmt_connection = KERN_DEBUG "\t\"%pI4/%d\" -> \"%pI4/%d\";\n";
+		fmt_declaration = KERN_DEBUG "\t\"%pI4/%d\"[style=%s, color=\"#%06x\"];\n";
+	} else if (bits == 128) {
+		fmt_connection = KERN_DEBUG "\t\"%pI6/%d\" -> \"%pI6/%d\";\n";
+		fmt_declaration = KERN_DEBUG "\t\"%pI6/%d\"[style=%s, color=\"#%06x\"];\n";
+	}
+	if (node->peer) {
+		hsiphash_key_t key = { { 0 } };
+
+		memcpy(&key, &node->peer, sizeof(node->peer));
+		color = hsiphash_1u32(0xdeadbeef, &key) % 200 << 16 |
+			hsiphash_1u32(0xbabecafe, &key) % 200 << 8 |
+			hsiphash_1u32(0xabad1dea, &key) % 200;
+		style = "bold";
+	}
+	wg_allowedips_read_node(node, ip1, &cidr1);
+	printk(fmt_declaration, ip1, cidr1, style, color);
+	if (node->bit[0]) {
+		wg_allowedips_read_node(rcu_dereference_raw(node->bit[0]), ip2, &cidr2);
+		printk(fmt_connection, ip1, cidr1, ip2, cidr2);
+	}
+	if (node->bit[1]) {
+		wg_allowedips_read_node(rcu_dereference_raw(node->bit[1]), ip2, &cidr2);
+		printk(fmt_connection, ip1, cidr1, ip2, cidr2);
+	}
+	if (node->bit[0])
+		print_node(rcu_dereference_raw(node->bit[0]), bits);
+	if (node->bit[1])
+		print_node(rcu_dereference_raw(node->bit[1]), bits);
+}
+
+static __init void print_tree(struct allowedips_node __rcu *top, u8 bits)
+{
+	printk(KERN_DEBUG "digraph trie {\n");
+	print_node(rcu_dereference_raw(top), bits);
+	printk(KERN_DEBUG "}\n");
+}
+
+enum {
+	NUM_PEERS = 2000,
+	NUM_RAND_ROUTES = 400,
+	NUM_MUTATED_ROUTES = 100,
+	NUM_QUERIES = NUM_RAND_ROUTES * NUM_MUTATED_ROUTES * 30
+};
+
+struct horrible_allowedips {
+	struct hlist_head head;
+};
+
+struct horrible_allowedips_node {
+	struct hlist_node table;
+	union nf_inet_addr ip;
+	union nf_inet_addr mask;
+	u8 ip_version;
+	void *value;
+};
+
+static __init void horrible_allowedips_init(struct horrible_allowedips *table)
+{
+	INIT_HLIST_HEAD(&table->head);
+}
+
+static __init void horrible_allowedips_free(struct horrible_allowedips *table)
+{
+	struct horrible_allowedips_node *node;
+	struct hlist_node *h;
+
+	hlist_for_each_entry_safe(node, h, &table->head, table) {
+		hlist_del(&node->table);
+		kfree(node);
+	}
+}
+
+static __init inline union nf_inet_addr horrible_cidr_to_mask(u8 cidr)
+{
+	union nf_inet_addr mask;
+
+	memset(&mask, 0, sizeof(mask));
+	memset(&mask.all, 0xff, cidr / 8);
+	if (cidr % 32)
+		mask.all[cidr / 32] = (__force u32)htonl(
+			(0xFFFFFFFFUL << (32 - (cidr % 32))) & 0xFFFFFFFFUL);
+	return mask;
+}
+
+static __init inline u8 horrible_mask_to_cidr(union nf_inet_addr subnet)
+{
+	return hweight32(subnet.all[0]) + hweight32(subnet.all[1]) +
+	       hweight32(subnet.all[2]) + hweight32(subnet.all[3]);
+}
+
+static __init inline void
+horrible_mask_self(struct horrible_allowedips_node *node)
+{
+	if (node->ip_version == 4) {
+		node->ip.ip &= node->mask.ip;
+	} else if (node->ip_version == 6) {
+		node->ip.ip6[0] &= node->mask.ip6[0];
+		node->ip.ip6[1] &= node->mask.ip6[1];
+		node->ip.ip6[2] &= node->mask.ip6[2];
+		node->ip.ip6[3] &= node->mask.ip6[3];
+	}
+}
+
+static __init inline bool
+horrible_match_v4(const struct horrible_allowedips_node *node, struct in_addr *ip)
+{
+	return (ip->s_addr & node->mask.ip) == node->ip.ip;
+}
+
+static __init inline bool
+horrible_match_v6(const struct horrible_allowedips_node *node, struct in6_addr *ip)
+{
+	return (ip->in6_u.u6_addr32[0] & node->mask.ip6[0]) == node->ip.ip6[0] &&
+	       (ip->in6_u.u6_addr32[1] & node->mask.ip6[1]) == node->ip.ip6[1] &&
+	       (ip->in6_u.u6_addr32[2] & node->mask.ip6[2]) == node->ip.ip6[2] &&
+	       (ip->in6_u.u6_addr32[3] & node->mask.ip6[3]) == node->ip.ip6[3];
+}
+
+static __init void
+horrible_insert_ordered(struct horrible_allowedips *table, struct horrible_allowedips_node *node)
+{
+	struct horrible_allowedips_node *other = NULL, *where = NULL;
+	u8 my_cidr = horrible_mask_to_cidr(node->mask);
+
+	hlist_for_each_entry(other, &table->head, table) {
+		if (other->ip_version == node->ip_version &&
+		    !memcmp(&other->mask, &node->mask, sizeof(union nf_inet_addr)) &&
+		    !memcmp(&other->ip, &node->ip, sizeof(union nf_inet_addr))) {
+			other->value = node->value;
+			kfree(node);
+			return;
+		}
+	}
+	hlist_for_each_entry(other, &table->head, table) {
+		where = other;
+		if (horrible_mask_to_cidr(other->mask) <= my_cidr)
+			break;
+	}
+	if (!other && !where)
+		hlist_add_head(&node->table, &table->head);
+	else if (!other)
+		hlist_add_behind(&node->table, &where->table);
+	else
+		hlist_add_before(&node->table, &where->table);
+}
+
+static __init int
+horrible_allowedips_insert_v4(struct horrible_allowedips *table,
+			      struct in_addr *ip, u8 cidr, void *value)
+{
+	struct horrible_allowedips_node *node = kzalloc_obj(*node);
+
+	if (unlikely(!node))
+		return -ENOMEM;
+	node->ip.in = *ip;
+	node->mask = horrible_cidr_to_mask(cidr);
+	node->ip_version = 4;
+	node->value = value;
+	horrible_mask_self(node);
+	horrible_insert_ordered(table, node);
+	return 0;
+}
+
+static __init int
+horrible_allowedips_insert_v6(struct horrible_allowedips *table,
+			      struct in6_addr *ip, u8 cidr, void *value)
+{
+	struct horrible_allowedips_node *node = kzalloc_obj(*node);
+
+	if (unlikely(!node))
+		return -ENOMEM;
+	node->ip.in6 = *ip;
+	node->mask = horrible_cidr_to_mask(cidr);
+	node->ip_version = 6;
+	node->value = value;
+	horrible_mask_self(node);
+	horrible_insert_ordered(table, node);
+	return 0;
+}
+
+static __init void *
+horrible_allowedips_lookup_v4(struct horrible_allowedips *table, struct in_addr *ip)
+{
+	struct horrible_allowedips_node *node;
+
+	hlist_for_each_entry(node, &table->head, table) {
+		if (node->ip_version == 4 && horrible_match_v4(node, ip))
+			return node->value;
+	}
+	return NULL;
+}
+
+static __init void *
+horrible_allowedips_lookup_v6(struct horrible_allowedips *table, struct in6_addr *ip)
+{
+	struct horrible_allowedips_node *node;
+
+	hlist_for_each_entry(node, &table->head, table) {
+		if (node->ip_version == 6 && horrible_match_v6(node, ip))
+			return node->value;
+	}
+	return NULL;
+}
+
+
+static __init void
+horrible_allowedips_remove_by_value(struct horrible_allowedips *table, void *value)
+{
+	struct horrible_allowedips_node *node;
+	struct hlist_node *h;
+
+	hlist_for_each_entry_safe(node, h, &table->head, table) {
+		if (node->value != value)
+			continue;
+		hlist_del(&node->table);
+		kfree(node);
+	}
+
+}
+
+static __init bool randomized_test(void)
+{
+	unsigned int i, j, k, mutate_amount, cidr;
+	u8 ip[16], mutate_mask[16], mutated[16];
+	struct wg_peer **peers, *peer;
+	struct horrible_allowedips h;
+	DEFINE_MUTEX(mutex);
+	struct allowedips t;
+	bool ret = false;
+
+	mutex_init(&mutex);
+
+	wg_allowedips_init(&t);
+	horrible_allowedips_init(&h);
+
+	peers = kzalloc_objs(*peers, NUM_PEERS);
+	if (unlikely(!peers)) {
+		pr_err("allowedips random self-test malloc: FAIL\n");
+		goto free;
+	}
+	for (i = 0; i < NUM_PEERS; ++i) {
+		peers[i] = kzalloc_obj(*peers[i]);
+		if (unlikely(!peers[i])) {
+			pr_err("allowedips random self-test malloc: FAIL\n");
+			goto free;
+		}
+		kref_init(&peers[i]->refcount);
+		INIT_LIST_HEAD(&peers[i]->allowedips_list);
+	}
+
+	mutex_lock(&mutex);
+
+	for (i = 0; i < NUM_RAND_ROUTES; ++i) {
+		get_random_bytes(ip, 4);
+		cidr = get_random_u32_inclusive(1, 32);
+		peer = peers[get_random_u32_below(NUM_PEERS)];
+		if (wg_allowedips_insert_v4(&t, (struct in_addr *)ip, cidr,
+					    peer, &mutex) < 0) {
+			pr_err("allowedips random self-test malloc: FAIL\n");
+			goto free_locked;
+		}
+		if (horrible_allowedips_insert_v4(&h, (struct in_addr *)ip,
+						  cidr, peer) < 0) {
+			pr_err("allowedips random self-test malloc: FAIL\n");
+			goto free_locked;
+		}
+		for (j = 0; j < NUM_MUTATED_ROUTES; ++j) {
+			memcpy(mutated, ip, 4);
+			get_random_bytes(mutate_mask, 4);
+			mutate_amount = get_random_u32_below(32);
+			for (k = 0; k < mutate_amount / 8; ++k)
+				mutate_mask[k] = 0xff;
+			mutate_mask[k] = 0xff
+					 << ((8 - (mutate_amount % 8)) % 8);
+			for (; k < 4; ++k)
+				mutate_mask[k] = 0;
+			for (k = 0; k < 4; ++k)
+				mutated[k] = (mutated[k] & mutate_mask[k]) |
+					     (~mutate_mask[k] &
+					      get_random_u8());
+			cidr = get_random_u32_inclusive(1, 32);
+			peer = peers[get_random_u32_below(NUM_PEERS)];
+			if (wg_allowedips_insert_v4(&t,
+						    (struct in_addr *)mutated,
+						    cidr, peer, &mutex) < 0) {
+				pr_err("allowedips random self-test malloc: FAIL\n");
+				goto free_locked;
+			}
+			if (horrible_allowedips_insert_v4(&h,
+				(struct in_addr *)mutated, cidr, peer)) {
+				pr_err("allowedips random self-test malloc: FAIL\n");
+				goto free_locked;
+			}
+		}
+	}
+
+	for (i = 0; i < NUM_RAND_ROUTES; ++i) {
+		get_random_bytes(ip, 16);
+		cidr = get_random_u32_inclusive(1, 128);
+		peer = peers[get_random_u32_below(NUM_PEERS)];
+		if (wg_allowedips_insert_v6(&t, (struct in6_addr *)ip, cidr,
+					    peer, &mutex) < 0) {
+			pr_err("allowedips random self-test malloc: FAIL\n");
+			goto free_locked;
+		}
+		if (horrible_allowedips_insert_v6(&h, (struct in6_addr *)ip,
+						  cidr, peer) < 0) {
+			pr_err("allowedips random self-test malloc: FAIL\n");
+			goto free_locked;
+		}
+		for (j = 0; j < NUM_MUTATED_ROUTES; ++j) {
+			memcpy(mutated, ip, 16);
+			get_random_bytes(mutate_mask, 16);
+			mutate_amount = get_random_u32_below(128);
+			for (k = 0; k < mutate_amount / 8; ++k)
+				mutate_mask[k] = 0xff;
+			mutate_mask[k] = 0xff
+					 << ((8 - (mutate_amount % 8)) % 8);
+			for (; k < 4; ++k)
+				mutate_mask[k] = 0;
+			for (k = 0; k < 4; ++k)
+				mutated[k] = (mutated[k] & mutate_mask[k]) |
+					     (~mutate_mask[k] &
+					      get_random_u8());
+			cidr = get_random_u32_inclusive(1, 128);
+			peer = peers[get_random_u32_below(NUM_PEERS)];
+			if (wg_allowedips_insert_v6(&t,
+						    (struct in6_addr *)mutated,
+						    cidr, peer, &mutex) < 0) {
+				pr_err("allowedips random self-test malloc: FAIL\n");
+				goto free_locked;
+			}
+			if (horrible_allowedips_insert_v6(
+				    &h, (struct in6_addr *)mutated, cidr,
+				    peer)) {
+				pr_err("allowedips random self-test malloc: FAIL\n");
+				goto free_locked;
+			}
+		}
+	}
+
+	mutex_unlock(&mutex);
+
+	if (IS_ENABLED(DEBUG_PRINT_TRIE_GRAPHVIZ)) {
+		print_tree(t.root4, 32);
+		print_tree(t.root6, 128);
+	}
+
+	for (j = 0;; ++j) {
+		for (i = 0; i < NUM_QUERIES; ++i) {
+			get_random_bytes(ip, 4);
+			if (lookup(t.root4, 32, ip) != horrible_allowedips_lookup_v4(&h, (struct in_addr *)ip)) {
+				pr_err("allowedips random v4 self-test: FAIL\n");
+				goto free;
+			}
+			get_random_bytes(ip, 16);
+			if (lookup(t.root6, 128, ip) != horrible_allowedips_lookup_v6(&h, (struct in6_addr *)ip)) {
+				pr_err("allowedips random v6 self-test: FAIL\n");
+				goto free;
+			}
+		}
+		if (j >= NUM_PEERS)
+			break;
+		mutex_lock(&mutex);
+		wg_allowedips_remove_by_peer(&t, peers[j], &mutex);
+		mutex_unlock(&mutex);
+		horrible_allowedips_remove_by_value(&h, peers[j]);
+	}
+
+	if (t.root4 || t.root6) {
+		pr_err("allowedips random self-test removal: FAIL\n");
+		goto free;
+	}
+
+	ret = true;
+
+free:
+	mutex_lock(&mutex);
+free_locked:
+	wg_allowedips_free(&t, &mutex);
+	mutex_unlock(&mutex);
+	horrible_allowedips_free(&h);
+	if (peers) {
+		for (i = 0; i < NUM_PEERS; ++i)
+			kfree(peers[i]);
+	}
+	kfree(peers);
+	return ret;
+}
+
+static __init inline struct in_addr *ip4(u8 a, u8 b, u8 c, u8 d)
+{
+	static struct in_addr ip;
+	u8 *split = (u8 *)&ip;
+
+	split[0] = a;
+	split[1] = b;
+	split[2] = c;
+	split[3] = d;
+	return &ip;
+}
+
+static __init inline struct in6_addr *ip6(u32 a, u32 b, u32 c, u32 d)
+{
+	static struct in6_addr ip;
+	__be32 *split = (__be32 *)&ip;
+
+	split[0] = cpu_to_be32(a);
+	split[1] = cpu_to_be32(b);
+	split[2] = cpu_to_be32(c);
+	split[3] = cpu_to_be32(d);
+	return &ip;
+}
+
+static __init struct wg_peer *init_peer(void)
+{
+	struct wg_peer *peer = kzalloc_obj(*peer);
+
+	if (!peer)
+		return NULL;
+	kref_init(&peer->refcount);
+	INIT_LIST_HEAD(&peer->allowedips_list);
+	return peer;
+}
+
+#define insert(version, mem, ipa, ipb, ipc, ipd, cidr)                       \
+	wg_allowedips_insert_v##version(&t, ip##version(ipa, ipb, ipc, ipd), \
+					cidr, mem, &mutex)
+
+#define remove(version, mem, ipa, ipb, ipc, ipd, cidr)                      \
+	wg_allowedips_remove_v##version(&t, ip##version(ipa, ipb, ipc, ipd), \
+					cidr, mem, &mutex)
+
+#define maybe_fail() do {                                               \
+		++i;                                                    \
+		if (!_s) {                                              \
+			pr_info("allowedips self-test %zu: FAIL\n", i); \
+			success = false;                                \
+		}                                                       \
+	} while (0)
+
+#define test(version, mem, ipa, ipb, ipc, ipd) do {                          \
+		bool _s = lookup(t.root##version, (version) == 4 ? 32 : 128, \
+				 ip##version(ipa, ipb, ipc, ipd)) == (mem);  \
+		maybe_fail();                                                \
+	} while (0)
+
+#define test_negative(version, mem, ipa, ipb, ipc, ipd) do {                 \
+		bool _s = lookup(t.root##version, (version) == 4 ? 32 : 128, \
+				 ip##version(ipa, ipb, ipc, ipd)) != (mem);  \
+		maybe_fail();                                                \
+	} while (0)
+
+#define test_boolean(cond) do {   \
+		bool _s = (cond); \
+		maybe_fail();     \
+	} while (0)
+
+bool __init wg_allowedips_selftest(void)
+{
+	bool found_a = false, found_b = false, found_c = false, found_d = false,
+	     found_e = false, found_other = false;
+	struct wg_peer *a = init_peer(), *b = init_peer(), *c = init_peer(),
+		       *d = init_peer(), *e = init_peer(), *f = init_peer(),
+		       *g = init_peer(), *h = init_peer();
+	struct allowedips_node *iter_node;
+	bool success = false;
+	struct allowedips t;
+	DEFINE_MUTEX(mutex);
+	struct in6_addr ip;
+	size_t i = 0, count = 0;
+	__be64 part;
+
+	mutex_init(&mutex);
+	mutex_lock(&mutex);
+	wg_allowedips_init(&t);
+
+	if (!a || !b || !c || !d || !e || !f || !g || !h) {
+		pr_err("allowedips self-test malloc: FAIL\n");
+		goto free;
+	}
+
+	insert(4, a, 192, 168, 4, 0, 24);
+	insert(4, b, 192, 168, 4, 4, 32);
+	insert(4, c, 192, 168, 0, 0, 16);
+	insert(4, d, 192, 95, 5, 64, 27);
+	/* replaces previous entry, and maskself is required */
+	insert(4, c, 192, 95, 5, 65, 27);
+	insert(6, d, 0x26075300, 0x60006b00, 0, 0xc05f0543, 128);
+	insert(6, c, 0x26075300, 0x60006b00, 0, 0, 64);
+	insert(4, e, 0, 0, 0, 0, 0);
+	insert(6, e, 0, 0, 0, 0, 0);
+	/* replaces previous entry */
+	insert(6, f, 0, 0, 0, 0, 0);
+	insert(6, g, 0x24046800, 0, 0, 0, 32);
+	/* maskself is required */
+	insert(6, h, 0x24046800, 0x40040800, 0xdeadbeef, 0xdeadbeef, 64);
+	insert(6, a, 0x24046800, 0x40040800, 0xdeadbeef, 0xdeadbeef, 128);
+	insert(6, c, 0x24446800, 0x40e40800, 0xdeaebeef, 0xdefbeef, 128);
+	insert(6, b, 0x24446800, 0xf0e40800, 0xeeaebeef, 0, 98);
+	insert(4, g, 64, 15, 112, 0, 20);
+	/* maskself is required */
+	insert(4, h, 64, 15, 123, 211, 25);
+	insert(4, a, 10, 0, 0, 0, 25);
+	insert(4, b, 10, 0, 0, 128, 25);
+	insert(4, a, 10, 1, 0, 0, 30);
+	insert(4, b, 10, 1, 0, 4, 30);
+	insert(4, c, 10, 1, 0, 8, 29);
+	insert(4, d, 10, 1, 0, 16, 29);
+
+	if (IS_ENABLED(DEBUG_PRINT_TRIE_GRAPHVIZ)) {
+		print_tree(t.root4, 32);
+		print_tree(t.root6, 128);
+	}
+
+	success = true;
+
+	test(4, a, 192, 168, 4, 20);
+	test(4, a, 192, 168, 4, 0);
+	test(4, b, 192, 168, 4, 4);
+	test(4, c, 192, 168, 200, 182);
+	test(4, c, 192, 95, 5, 68);
+	test(4, e, 192, 95, 5, 96);
+	test(6, d, 0x26075300, 0x60006b00, 0, 0xc05f0543);
+	test(6, c, 0x26075300, 0x60006b00, 0, 0xc02e01ee);
+	test(6, f, 0x26075300, 0x60006b01, 0, 0);
+	test(6, g, 0x24046800, 0x40040806, 0, 0x1006);
+	test(6, g, 0x24046800, 0x40040806, 0x1234, 0x5678);
+	test(6, f, 0x240467ff, 0x40040806, 0x1234, 0x5678);
+	test(6, f, 0x24046801, 0x40040806, 0x1234, 0x5678);
+	test(6, h, 0x24046800, 0x40040800, 0x1234, 0x5678);
+	test(6, h, 0x24046800, 0x40040800, 0, 0);
+	test(6, h, 0x24046800, 0x40040800, 0x10101010, 0x10101010);
+	test(6, a, 0x24046800, 0x40040800, 0xdeadbeef, 0xdeadbeef);
+	test(4, g, 64, 15, 116, 26);
+	test(4, g, 64, 15, 127, 3);
+	test(4, g, 64, 15, 123, 1);
+	test(4, h, 64, 15, 123, 128);
+	test(4, h, 64, 15, 123, 129);
+	test(4, a, 10, 0, 0, 52);
+	test(4, b, 10, 0, 0, 220);
+	test(4, a, 10, 1, 0, 2);
+	test(4, b, 10, 1, 0, 6);
+	test(4, c, 10, 1, 0, 10);
+	test(4, d, 10, 1, 0, 20);
+
+	insert(4, a, 1, 0, 0, 0, 32);
+	insert(4, a, 64, 0, 0, 0, 32);
+	insert(4, a, 128, 0, 0, 0, 32);
+	insert(4, a, 192, 0, 0, 0, 32);
+	insert(4, a, 255, 0, 0, 0, 32);
+	wg_allowedips_remove_by_peer(&t, a, &mutex);
+	test_negative(4, a, 1, 0, 0, 0);
+	test_negative(4, a, 64, 0, 0, 0);
+	test_negative(4, a, 128, 0, 0, 0);
+	test_negative(4, a, 192, 0, 0, 0);
+	test_negative(4, a, 255, 0, 0, 0);
+
+	insert(4, a, 1, 0, 0, 0, 32);
+	insert(4, a, 192, 0, 0, 0, 24);
+	insert(6, a, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef, 128);
+	insert(6, a, 0x24446800, 0xf0e40800, 0xeeaebeef, 0, 98);
+	test(4, a, 1, 0, 0, 0);
+	test(4, a, 192, 0, 0, 1);
+	test(6, a, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef);
+	test(6, a, 0x24446800, 0xf0e40800, 0xeeaebeef, 0x10101010);
+	/* Must be an exact match to remove */
+	remove(4, a, 192, 0, 0, 0, 32);
+	test(4, a, 192, 0, 0, 1);
+	/* NULL peer should have no effect and return 0 */
+	test_boolean(!remove(4, NULL, 192, 0, 0, 0, 24));
+	test(4, a, 192, 0, 0, 1);
+	/* different peer should have no effect and return 0 */
+	test_boolean(!remove(4, b, 192, 0, 0, 0, 24));
+	test(4, a, 192, 0, 0, 1);
+	/* invalid CIDR should have no effect and return -EINVAL */
+	test_boolean(remove(4, b, 192, 0, 0, 0, 33) == -EINVAL);
+	test(4, a, 192, 0, 0, 1);
+	remove(4, a, 192, 0, 0, 0, 24);
+	test_negative(4, a, 192, 0, 0, 1);
+	remove(4, a, 1, 0, 0, 0, 32);
+	test_negative(4, a, 1, 0, 0, 0);
+	/* Must be an exact match to remove */
+	remove(6, a, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef, 96);
+	test(6, a, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef);
+	/* NULL peer should have no effect and return 0 */
+	test_boolean(!remove(6, NULL, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef, 128));
+	test(6, a, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef);
+	/* different peer should have no effect and return 0 */
+	test_boolean(!remove(6, b, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef, 128));
+	test(6, a, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef);
+	/* invalid CIDR should have no effect and return -EINVAL */
+	test_boolean(remove(6, a, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef, 129) == -EINVAL);
+	test(6, a, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef);
+	remove(6, a, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef, 128);
+	test_negative(6, a, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef);
+	/* Must match the peer to remove */
+	remove(6, b, 0x24446800, 0xf0e40800, 0xeeaebeef, 0, 98);
+	test(6, a, 0x24446800, 0xf0e40800, 0xeeaebeef, 0x10101010);
+	remove(6, a, 0x24446800, 0xf0e40800, 0xeeaebeef, 0, 98);
+	test_negative(6, a, 0x24446800, 0xf0e40800, 0xeeaebeef, 0x10101010);
+
+	wg_allowedips_free(&t, &mutex);
+	wg_allowedips_init(&t);
+	insert(4, a, 192, 168, 0, 0, 16);
+	insert(4, a, 192, 168, 0, 0, 24);
+	wg_allowedips_remove_by_peer(&t, a, &mutex);
+	test_negative(4, a, 192, 168, 0, 1);
+
+	/* These will hit the WARN_ON(len >= MAX_ALLOWEDIPS_DEPTH) in free_node
+	 * if something goes wrong.
+	 */
+	for (i = 0; i < 64; ++i) {
+		part = cpu_to_be64(~0LLU << i);
+		memset(&ip, 0xff, 8);
+		memcpy((u8 *)&ip + 8, &part, 8);
+		wg_allowedips_insert_v6(&t, &ip, 128, a, &mutex);
+		memcpy(&ip, &part, 8);
+		memset((u8 *)&ip + 8, 0, 8);
+		wg_allowedips_insert_v6(&t, &ip, 128, a, &mutex);
+	}
+	memset(&ip, 0, 16);
+	wg_allowedips_insert_v6(&t, &ip, 128, a, &mutex);
+	wg_allowedips_free(&t, &mutex);
+
+	wg_allowedips_init(&t);
+	insert(4, a, 192, 95, 5, 93, 27);
+	insert(6, a, 0x26075300, 0x60006b00, 0, 0xc05f0543, 128);
+	insert(4, a, 10, 1, 0, 20, 29);
+	insert(6, a, 0x26075300, 0x6d8a6bf8, 0xdab1f1df, 0xc05f1523, 83);
+	insert(6, a, 0x26075300, 0x6d8a6bf8, 0xdab1f1df, 0xc05f1523, 21);
+	list_for_each_entry(iter_node, &a->allowedips_list, peer_list) {
+		u8 cidr, ip[16] __aligned(__alignof(u64));
+		int family = wg_allowedips_read_node(iter_node, ip, &cidr);
+
+		count++;
+
+		if (cidr == 27 && family == AF_INET &&
+		    !memcmp(ip, ip4(192, 95, 5, 64), sizeof(struct in_addr)))
+			found_a = true;
+		else if (cidr == 128 && family == AF_INET6 &&
+			 !memcmp(ip, ip6(0x26075300, 0x60006b00, 0, 0xc05f0543),
+				 sizeof(struct in6_addr)))
+			found_b = true;
+		else if (cidr == 29 && family == AF_INET &&
+			 !memcmp(ip, ip4(10, 1, 0, 16), sizeof(struct in_addr)))
+			found_c = true;
+		else if (cidr == 83 && family == AF_INET6 &&
+			 !memcmp(ip, ip6(0x26075300, 0x6d8a6bf8, 0xdab1e000, 0),
+				 sizeof(struct in6_addr)))
+			found_d = true;
+		else if (cidr == 21 && family == AF_INET6 &&
+			 !memcmp(ip, ip6(0x26075000, 0, 0, 0),
+				 sizeof(struct in6_addr)))
+			found_e = true;
+		else
+			found_other = true;
+	}
+	test_boolean(count == 5);
+	test_boolean(found_a);
+	test_boolean(found_b);
+	test_boolean(found_c);
+	test_boolean(found_d);
+	test_boolean(found_e);
+	test_boolean(!found_other);
+
+	if (IS_ENABLED(DEBUG_RANDOM_TRIE) && success)
+		success = randomized_test();
+
+	if (success)
+		pr_info("allowedips self-tests: pass\n");
+
+free:
+	wg_allowedips_free(&t, &mutex);
+	kfree(a);
+	kfree(b);
+	kfree(c);
+	kfree(d);
+	kfree(e);
+	kfree(f);
+	kfree(g);
+	kfree(h);
+	mutex_unlock(&mutex);
+
+	return success;
+}
+
+#undef test_negative
+#undef test
+#undef remove
+#undef insert
+#undef init_peer
+
+#endif

linux-7.2.3/drivers/net/wireguard/selftest/counter.c

@@ -0,0 +1,111 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#ifdef DEBUG
+bool __init wg_packet_counter_selftest(void)
+{
+	struct noise_replay_counter *counter;
+	unsigned int test_num = 0, i;
+	bool success = true;
+
+	counter = kmalloc_obj(*counter);
+	if (unlikely(!counter)) {
+		pr_err("nonce counter self-test malloc: FAIL\n");
+		return false;
+	}
+
+#define T_INIT do {                                    \
+		memset(counter, 0, sizeof(*counter));  \
+		spin_lock_init(&counter->lock);        \
+	} while (0)
+#define T_LIM (COUNTER_WINDOW_SIZE + 1)
+#define T(n, v) do {                                                  \
+		++test_num;                                           \
+		if (counter_validate(counter, n) != (v)) {            \
+			pr_err("nonce counter self-test %u: FAIL\n",  \
+			       test_num);                             \
+			success = false;                              \
+		}                                                     \
+	} while (0)
+
+	T_INIT;
+	/*  1 */ T(0, true);
+	/*  2 */ T(1, true);
+	/*  3 */ T(1, false);
+	/*  4 */ T(9, true);
+	/*  5 */ T(8, true);
+	/*  6 */ T(7, true);
+	/*  7 */ T(7, false);
+	/*  8 */ T(T_LIM, true);
+	/*  9 */ T(T_LIM - 1, true);
+	/* 10 */ T(T_LIM - 1, false);
+	/* 11 */ T(T_LIM - 2, true);
+	/* 12 */ T(2, true);
+	/* 13 */ T(2, false);
+	/* 14 */ T(T_LIM + 16, true);
+	/* 15 */ T(3, false);
+	/* 16 */ T(T_LIM + 16, false);
+	/* 17 */ T(T_LIM * 4, true);
+	/* 18 */ T(T_LIM * 4 - (T_LIM - 1), true);
+	/* 19 */ T(10, false);
+	/* 20 */ T(T_LIM * 4 - T_LIM, false);
+	/* 21 */ T(T_LIM * 4 - (T_LIM + 1), false);
+	/* 22 */ T(T_LIM * 4 - (T_LIM - 2), true);
+	/* 23 */ T(T_LIM * 4 + 1 - T_LIM, false);
+	/* 24 */ T(0, false);
+	/* 25 */ T(REJECT_AFTER_MESSAGES, false);
+	/* 26 */ T(REJECT_AFTER_MESSAGES - 1, true);
+	/* 27 */ T(REJECT_AFTER_MESSAGES, false);
+	/* 28 */ T(REJECT_AFTER_MESSAGES - 1, false);
+	/* 29 */ T(REJECT_AFTER_MESSAGES - 2, true);
+	/* 30 */ T(REJECT_AFTER_MESSAGES + 1, false);
+	/* 31 */ T(REJECT_AFTER_MESSAGES + 2, false);
+	/* 32 */ T(REJECT_AFTER_MESSAGES - 2, false);
+	/* 33 */ T(REJECT_AFTER_MESSAGES - 3, true);
+	/* 34 */ T(0, false);
+
+	T_INIT;
+	for (i = 1; i <= COUNTER_WINDOW_SIZE; ++i)
+		T(i, true);
+	T(0, true);
+	T(0, false);
+
+	T_INIT;
+	for (i = 2; i <= COUNTER_WINDOW_SIZE + 1; ++i)
+		T(i, true);
+	T(1, true);
+	T(0, false);
+
+	T_INIT;
+	for (i = COUNTER_WINDOW_SIZE + 1; i-- > 0;)
+		T(i, true);
+
+	T_INIT;
+	for (i = COUNTER_WINDOW_SIZE + 2; i-- > 1;)
+		T(i, true);
+	T(0, false);
+
+	T_INIT;
+	for (i = COUNTER_WINDOW_SIZE + 1; i-- > 1;)
+		T(i, true);
+	T(COUNTER_WINDOW_SIZE + 1, true);
+	T(0, false);
+
+	T_INIT;
+	for (i = COUNTER_WINDOW_SIZE + 1; i-- > 1;)
+		T(i, true);
+	T(0, true);
+	T(COUNTER_WINDOW_SIZE + 1, true);
+
+#undef T
+#undef T_LIM
+#undef T_INIT
+
+	if (success)
+		pr_info("nonce counter self-tests: pass\n");
+	kfree(counter);
+	return success;
+}
+#endif

linux-7.2.3/drivers/net/wireguard/selftest/ratelimiter.c

@@ -0,0 +1,224 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#ifdef DEBUG
+
+#include <linux/jiffies.h>
+
+static const struct {
+	bool result;
+	unsigned int msec_to_sleep_before;
+} expected_results[] __initconst = {
+	[0 ... PACKETS_BURSTABLE - 1] = { true, 0 },
+	[PACKETS_BURSTABLE] = { false, 0 },
+	[PACKETS_BURSTABLE + 1] = { true, MSEC_PER_SEC / PACKETS_PER_SECOND },
+	[PACKETS_BURSTABLE + 2] = { false, 0 },
+	[PACKETS_BURSTABLE + 3] = { true, (MSEC_PER_SEC / PACKETS_PER_SECOND) * 2 },
+	[PACKETS_BURSTABLE + 4] = { true, 0 },
+	[PACKETS_BURSTABLE + 5] = { false, 0 }
+};
+
+static __init unsigned int maximum_jiffies_at_index(int index)
+{
+	unsigned int total_msecs = 2 * MSEC_PER_SEC / PACKETS_PER_SECOND / 3;
+	int i;
+
+	for (i = 0; i <= index; ++i)
+		total_msecs += expected_results[i].msec_to_sleep_before;
+	return msecs_to_jiffies(total_msecs);
+}
+
+static __init int timings_test(struct sk_buff *skb4, struct iphdr *hdr4,
+			       struct sk_buff *skb6, struct ipv6hdr *hdr6,
+			       int *test)
+{
+	unsigned long loop_start_time;
+	int i;
+
+	wg_ratelimiter_gc_entries(NULL);
+	rcu_barrier();
+	loop_start_time = jiffies;
+
+	for (i = 0; i < ARRAY_SIZE(expected_results); ++i) {
+		if (expected_results[i].msec_to_sleep_before)
+			msleep(expected_results[i].msec_to_sleep_before);
+
+		if (time_is_before_jiffies(loop_start_time +
+					   maximum_jiffies_at_index(i)))
+			return -ETIMEDOUT;
+		if (wg_ratelimiter_allow(skb4, &init_net) !=
+					expected_results[i].result)
+			return -EXFULL;
+		++(*test);
+
+		hdr4->saddr = htonl(ntohl(hdr4->saddr) + i + 1);
+		if (time_is_before_jiffies(loop_start_time +
+					   maximum_jiffies_at_index(i)))
+			return -ETIMEDOUT;
+		if (!wg_ratelimiter_allow(skb4, &init_net))
+			return -EXFULL;
+		++(*test);
+
+		hdr4->saddr = htonl(ntohl(hdr4->saddr) - i - 1);
+
+#if IS_ENABLED(CONFIG_IPV6)
+		hdr6->saddr.in6_u.u6_addr32[2] = htonl(i);
+		hdr6->saddr.in6_u.u6_addr32[3] = htonl(i);
+		if (time_is_before_jiffies(loop_start_time +
+					   maximum_jiffies_at_index(i)))
+			return -ETIMEDOUT;
+		if (wg_ratelimiter_allow(skb6, &init_net) !=
+					expected_results[i].result)
+			return -EXFULL;
+		++(*test);
+
+		hdr6->saddr.in6_u.u6_addr32[0] =
+			htonl(ntohl(hdr6->saddr.in6_u.u6_addr32[0]) + i + 1);
+		if (time_is_before_jiffies(loop_start_time +
+					   maximum_jiffies_at_index(i)))
+			return -ETIMEDOUT;
+		if (!wg_ratelimiter_allow(skb6, &init_net))
+			return -EXFULL;
+		++(*test);
+
+		hdr6->saddr.in6_u.u6_addr32[0] =
+			htonl(ntohl(hdr6->saddr.in6_u.u6_addr32[0]) - i - 1);
+
+		if (time_is_before_jiffies(loop_start_time +
+					   maximum_jiffies_at_index(i)))
+			return -ETIMEDOUT;
+#endif
+	}
+	return 0;
+}
+
+static __init int capacity_test(struct sk_buff *skb4, struct iphdr *hdr4,
+				int *test)
+{
+	int i;
+
+	wg_ratelimiter_gc_entries(NULL);
+	rcu_barrier();
+
+	if (atomic_read(&total_entries))
+		return -EXFULL;
+	++(*test);
+
+	for (i = 0; i <= max_entries; ++i) {
+		hdr4->saddr = htonl(i);
+		if (wg_ratelimiter_allow(skb4, &init_net) != (i != max_entries))
+			return -EXFULL;
+		++(*test);
+	}
+	return 0;
+}
+
+bool __init wg_ratelimiter_selftest(void)
+{
+	enum { TRIALS_BEFORE_GIVING_UP = 5000 };
+	bool success = false;
+	int test = 0, trials;
+	struct sk_buff *skb4, *skb6 = NULL;
+	struct iphdr *hdr4;
+	struct ipv6hdr *hdr6 = NULL;
+
+	if (IS_ENABLED(CONFIG_KASAN) || IS_ENABLED(CONFIG_UBSAN))
+		return true;
+
+	BUILD_BUG_ON(MSEC_PER_SEC % PACKETS_PER_SECOND != 0);
+
+	if (wg_ratelimiter_init())
+		goto out;
+	++test;
+	if (wg_ratelimiter_init()) {
+		wg_ratelimiter_uninit();
+		goto out;
+	}
+	++test;
+	if (wg_ratelimiter_init()) {
+		wg_ratelimiter_uninit();
+		wg_ratelimiter_uninit();
+		goto out;
+	}
+	++test;
+
+	skb4 = alloc_skb(sizeof(struct iphdr), GFP_KERNEL);
+	if (unlikely(!skb4))
+		goto err_nofree;
+	skb4->protocol = htons(ETH_P_IP);
+	hdr4 = (struct iphdr *)skb_put(skb4, sizeof(*hdr4));
+	hdr4->saddr = htonl(8182);
+	skb_reset_network_header(skb4);
+	++test;
+
+#if IS_ENABLED(CONFIG_IPV6)
+	skb6 = alloc_skb(sizeof(struct ipv6hdr), GFP_KERNEL);
+	if (unlikely(!skb6)) {
+		kfree_skb(skb4);
+		goto err_nofree;
+	}
+	skb6->protocol = htons(ETH_P_IPV6);
+	hdr6 = (struct ipv6hdr *)skb_put(skb6, sizeof(*hdr6));
+	hdr6->saddr.in6_u.u6_addr32[0] = htonl(1212);
+	hdr6->saddr.in6_u.u6_addr32[1] = htonl(289188);
+	skb_reset_network_header(skb6);
+	++test;
+#endif
+
+	for (trials = TRIALS_BEFORE_GIVING_UP; IS_ENABLED(DEBUG_RATELIMITER_TIMINGS);) {
+		int test_count = 0, ret;
+
+		ret = timings_test(skb4, hdr4, skb6, hdr6, &test_count);
+		if (ret == -ETIMEDOUT) {
+			if (!trials--) {
+				test += test_count;
+				goto err;
+			}
+			continue;
+		} else if (ret < 0) {
+			test += test_count;
+			goto err;
+		} else {
+			test += test_count;
+			break;
+		}
+	}
+
+	for (trials = TRIALS_BEFORE_GIVING_UP;;) {
+		int test_count = 0;
+
+		if (capacity_test(skb4, hdr4, &test_count) < 0) {
+			if (!trials--) {
+				test += test_count;
+				goto err;
+			}
+			continue;
+		}
+		test += test_count;
+		break;
+	}
+
+	success = true;
+
+err:
+	kfree_skb(skb4);
+#if IS_ENABLED(CONFIG_IPV6)
+	kfree_skb(skb6);
+#endif
+err_nofree:
+	wg_ratelimiter_uninit();
+	wg_ratelimiter_uninit();
+	wg_ratelimiter_uninit();
+	/* Uninit one extra time to check underflow detection. */
+	wg_ratelimiter_uninit();
+out:
+	if (success)
+		pr_info("ratelimiter self-tests: pass\n");
+	else
+		pr_err("ratelimiter self-test %d: FAIL\n", test);
+
+	return success;
+}
+#endif

linux-7.2.3/drivers/net/wireguard/send.c

@@ -0,0 +1,414 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include "queueing.h"
+#include "timers.h"
+#include "device.h"
+#include "peer.h"
+#include "socket.h"
+#include "messages.h"
+#include "cookie.h"
+
+#include <linux/uio.h>
+#include <linux/inetdevice.h>
+#include <linux/socket.h>
+#include <net/ip_tunnels.h>
+#include <net/udp.h>
+#include <net/sock.h>
+
+static void wg_packet_send_handshake_initiation(struct wg_peer *peer)
+{
+	struct message_handshake_initiation packet;
+
+	if (!wg_birthdate_has_expired(atomic64_read(&peer->last_sent_handshake),
+				      REKEY_TIMEOUT))
+		return; /* This function is rate limited. */
+
+	atomic64_set(&peer->last_sent_handshake, ktime_get_coarse_boottime_ns());
+	net_dbg_ratelimited("%s: Sending handshake initiation to peer %llu (%pISpfsc)\n",
+			    peer->device->dev->name, peer->internal_id,
+			    &peer->endpoint.addr);
+
+	if (wg_noise_handshake_create_initiation(&packet, &peer->handshake)) {
+		wg_cookie_add_mac_to_packet(&packet, sizeof(packet), peer);
+		wg_timers_any_authenticated_packet_traversal(peer);
+		wg_timers_any_authenticated_packet_sent(peer);
+		atomic64_set(&peer->last_sent_handshake,
+			     ktime_get_coarse_boottime_ns());
+		wg_socket_send_buffer_to_peer(peer, &packet, sizeof(packet),
+					      HANDSHAKE_DSCP);
+		wg_timers_handshake_initiated(peer);
+	}
+}
+
+void wg_packet_handshake_send_worker(struct work_struct *work)
+{
+	struct wg_peer *peer = container_of(work, struct wg_peer,
+					    transmit_handshake_work);
+
+	wg_packet_send_handshake_initiation(peer);
+	wg_peer_put(peer);
+}
+
+void wg_packet_send_queued_handshake_initiation(struct wg_peer *peer,
+						bool is_retry)
+{
+	if (!is_retry)
+		peer->timer_handshake_attempts = 0;
+
+	rcu_read_lock_bh();
+	/* We check last_sent_handshake here in addition to the actual function
+	 * we're queueing up, so that we don't queue things if not strictly
+	 * necessary:
+	 */
+	if (!wg_birthdate_has_expired(atomic64_read(&peer->last_sent_handshake),
+				      REKEY_TIMEOUT) ||
+			unlikely(READ_ONCE(peer->is_dead)))
+		goto out;
+
+	wg_peer_get(peer);
+	/* Queues up calling packet_send_queued_handshakes(peer), where we do a
+	 * peer_put(peer) after:
+	 */
+	if (!queue_work(peer->device->handshake_send_wq,
+			&peer->transmit_handshake_work))
+		/* If the work was already queued, we want to drop the
+		 * extra reference:
+		 */
+		wg_peer_put(peer);
+out:
+	rcu_read_unlock_bh();
+}
+
+void wg_packet_send_handshake_response(struct wg_peer *peer)
+{
+	struct message_handshake_response packet;
+
+	atomic64_set(&peer->last_sent_handshake, ktime_get_coarse_boottime_ns());
+	net_dbg_ratelimited("%s: Sending handshake response to peer %llu (%pISpfsc)\n",
+			    peer->device->dev->name, peer->internal_id,
+			    &peer->endpoint.addr);
+
+	if (wg_noise_handshake_create_response(&packet, &peer->handshake)) {
+		wg_cookie_add_mac_to_packet(&packet, sizeof(packet), peer);
+		if (wg_noise_handshake_begin_session(&peer->handshake,
+						     &peer->keypairs)) {
+			wg_timers_session_derived(peer);
+			wg_timers_any_authenticated_packet_traversal(peer);
+			wg_timers_any_authenticated_packet_sent(peer);
+			atomic64_set(&peer->last_sent_handshake,
+				     ktime_get_coarse_boottime_ns());
+			wg_socket_send_buffer_to_peer(peer, &packet,
+						      sizeof(packet),
+						      HANDSHAKE_DSCP);
+		}
+	}
+}
+
+void wg_packet_send_handshake_cookie(struct wg_device *wg,
+				     struct sk_buff *initiating_skb,
+				     __le32 sender_index)
+{
+	struct message_handshake_cookie packet;
+
+	net_dbg_skb_ratelimited("%s: Sending cookie response for denied handshake message for %pISpfsc\n",
+				wg->dev->name, initiating_skb);
+	wg_cookie_message_create(&packet, initiating_skb, sender_index,
+				 &wg->cookie_checker);
+	wg_socket_send_buffer_as_reply_to_skb(wg, initiating_skb, &packet,
+					      sizeof(packet));
+}
+
+static void keep_key_fresh(struct wg_peer *peer)
+{
+	struct noise_keypair *keypair;
+	bool send;
+
+	rcu_read_lock_bh();
+	keypair = rcu_dereference_bh(peer->keypairs.current_keypair);
+	send = keypair && READ_ONCE(keypair->sending.is_valid) &&
+	       (atomic64_read(&keypair->sending_counter) > REKEY_AFTER_MESSAGES ||
+		(keypair->i_am_the_initiator &&
+		 wg_birthdate_has_expired(keypair->sending.birthdate, REKEY_AFTER_TIME)));
+	rcu_read_unlock_bh();
+
+	if (unlikely(send))
+		wg_packet_send_queued_handshake_initiation(peer, false);
+}
+
+static unsigned int calculate_skb_padding(struct sk_buff *skb)
+{
+	unsigned int padded_size, last_unit = skb->len;
+
+	if (unlikely(!PACKET_CB(skb)->mtu))
+		return ALIGN(last_unit, MESSAGE_PADDING_MULTIPLE) - last_unit;
+
+	/* We do this modulo business with the MTU, just in case the networking
+	 * layer gives us a packet that's bigger than the MTU. In that case, we
+	 * wouldn't want the final subtraction to overflow in the case of the
+	 * padded_size being clamped. Fortunately, that's very rarely the case,
+	 * so we optimize for that not happening.
+	 */
+	if (unlikely(last_unit > PACKET_CB(skb)->mtu))
+		last_unit %= PACKET_CB(skb)->mtu;
+
+	padded_size = min(PACKET_CB(skb)->mtu,
+			  ALIGN(last_unit, MESSAGE_PADDING_MULTIPLE));
+	return padded_size - last_unit;
+}
+
+static bool encrypt_packet(struct sk_buff *skb, struct noise_keypair *keypair)
+{
+	unsigned int padding_len, plaintext_len, trailer_len;
+	struct scatterlist sg[MAX_SKB_FRAGS + 8];
+	struct message_data *header;
+	struct sk_buff *trailer;
+	int num_frags;
+
+	/* Force hash calculation before encryption so that flow analysis is
+	 * consistent over the inner packet.
+	 */
+	skb_get_hash(skb);
+
+	/* Calculate lengths. */
+	padding_len = calculate_skb_padding(skb);
+	trailer_len = padding_len + noise_encrypted_len(0);
+	plaintext_len = skb->len + padding_len;
+
+	/* Expand head section to have room for our header and the network
+	 * stack's headers.
+	 */
+	if (unlikely(skb_cow_head(skb, DATA_PACKET_HEAD_ROOM) < 0))
+		return false;
+
+	/* Finalize checksum calculation for the inner packet, if required. */
+	if (unlikely(skb->ip_summed == CHECKSUM_PARTIAL &&
+		     skb_checksum_help(skb)))
+		return false;
+
+	/* Expand data section to have room for padding and auth tag. */
+	num_frags = skb_cow_data(skb, trailer_len, &trailer);
+	if (unlikely(num_frags < 0 || num_frags > ARRAY_SIZE(sg)))
+		return false;
+
+	/* Set the padding to zeros, and make sure it and the auth tag are part
+	 * of the skb.
+	 */
+	memset(skb_tail_pointer(trailer), 0, padding_len);
+
+	/* Only after checksumming can we safely add on the padding at the end
+	 * and the header.
+	 */
+	skb_set_inner_network_header(skb, 0);
+	header = (struct message_data *)skb_push(skb, sizeof(*header));
+	header->header.type = cpu_to_le32(MESSAGE_DATA);
+	header->key_idx = keypair->remote_index;
+	header->counter = cpu_to_le64(PACKET_CB(skb)->nonce);
+	pskb_put(skb, trailer, trailer_len);
+
+	/* Now we can encrypt the scattergather segments */
+	sg_init_table(sg, num_frags);
+	if (skb_to_sgvec(skb, sg, sizeof(struct message_data),
+			 noise_encrypted_len(plaintext_len)) <= 0)
+		return false;
+	return chacha20poly1305_encrypt_sg_inplace(sg, plaintext_len, NULL, 0,
+						   PACKET_CB(skb)->nonce,
+						   keypair->sending.key);
+}
+
+void wg_packet_send_keepalive(struct wg_peer *peer)
+{
+	struct sk_buff *skb;
+
+	if (skb_queue_empty_lockless(&peer->staged_packet_queue)) {
+		skb = alloc_skb(DATA_PACKET_HEAD_ROOM + MESSAGE_MINIMUM_LENGTH,
+				GFP_ATOMIC);
+		if (unlikely(!skb))
+			return;
+		skb_reserve(skb, DATA_PACKET_HEAD_ROOM);
+		skb->dev = peer->device->dev;
+		PACKET_CB(skb)->mtu = skb->dev->mtu;
+		skb_queue_tail(&peer->staged_packet_queue, skb);
+		net_dbg_ratelimited("%s: Sending keepalive packet to peer %llu (%pISpfsc)\n",
+				    peer->device->dev->name, peer->internal_id,
+				    &peer->endpoint.addr);
+	}
+
+	wg_packet_send_staged_packets(peer);
+}
+
+static void wg_packet_create_data_done(struct wg_peer *peer, struct sk_buff *first)
+{
+	struct sk_buff *skb, *next;
+	bool is_keepalive, data_sent = false;
+
+	wg_timers_any_authenticated_packet_traversal(peer);
+	wg_timers_any_authenticated_packet_sent(peer);
+	skb_list_walk_safe(first, skb, next) {
+		is_keepalive = skb->len == message_data_len(0);
+		if (likely(!wg_socket_send_skb_to_peer(peer, skb,
+				PACKET_CB(skb)->ds) && !is_keepalive))
+			data_sent = true;
+	}
+
+	if (likely(data_sent))
+		wg_timers_data_sent(peer);
+
+	keep_key_fresh(peer);
+}
+
+void wg_packet_tx_worker(struct work_struct *work)
+{
+	struct wg_peer *peer = container_of(work, struct wg_peer, transmit_packet_work);
+	struct noise_keypair *keypair;
+	enum packet_state state;
+	struct sk_buff *first;
+
+	while ((first = wg_prev_queue_peek(&peer->tx_queue)) != NULL &&
+	       (state = atomic_read_acquire(&PACKET_CB(first)->state)) !=
+		       PACKET_STATE_UNCRYPTED) {
+		wg_prev_queue_drop_peeked(&peer->tx_queue);
+		keypair = PACKET_CB(first)->keypair;
+
+		if (likely(state == PACKET_STATE_CRYPTED))
+			wg_packet_create_data_done(peer, first);
+		else
+			kfree_skb_list(first);
+
+		wg_noise_keypair_put(keypair, false);
+		wg_peer_put(peer);
+		if (need_resched())
+			cond_resched();
+	}
+}
+
+void wg_packet_encrypt_worker(struct work_struct *work)
+{
+	struct crypt_queue *queue = container_of(work, struct multicore_worker,
+						 work)->ptr;
+	struct sk_buff *first, *skb, *next;
+
+	while ((first = ptr_ring_consume_bh(&queue->ring)) != NULL) {
+		enum packet_state state = PACKET_STATE_CRYPTED;
+
+		skb_list_walk_safe(first, skb, next) {
+			if (likely(encrypt_packet(skb,
+					PACKET_CB(first)->keypair))) {
+				wg_reset_packet(skb, true);
+			} else {
+				state = PACKET_STATE_DEAD;
+				break;
+			}
+		}
+		wg_queue_enqueue_per_peer_tx(first, state);
+		if (need_resched())
+			cond_resched();
+	}
+}
+
+static void wg_packet_create_data(struct wg_peer *peer, struct sk_buff *first)
+{
+	struct wg_device *wg = peer->device;
+	int ret = -EINVAL;
+
+	rcu_read_lock_bh();
+	if (unlikely(READ_ONCE(peer->is_dead)))
+		goto err;
+
+	ret = wg_queue_enqueue_per_device_and_peer(&wg->encrypt_queue, &peer->tx_queue, first,
+						   wg->packet_crypt_wq);
+	if (unlikely(ret == -EPIPE))
+		wg_queue_enqueue_per_peer_tx(first, PACKET_STATE_DEAD);
+err:
+	rcu_read_unlock_bh();
+	if (likely(!ret || ret == -EPIPE))
+		return;
+	wg_noise_keypair_put(PACKET_CB(first)->keypair, false);
+	wg_peer_put(peer);
+	kfree_skb_list(first);
+}
+
+void wg_packet_purge_staged_packets(struct wg_peer *peer)
+{
+	spin_lock_bh(&peer->staged_packet_queue.lock);
+	DEV_STATS_ADD(peer->device->dev, tx_dropped,
+		      peer->staged_packet_queue.qlen);
+	__skb_queue_purge(&peer->staged_packet_queue);
+	spin_unlock_bh(&peer->staged_packet_queue.lock);
+}
+
+void wg_packet_send_staged_packets(struct wg_peer *peer)
+{
+	struct noise_keypair *keypair;
+	struct sk_buff_head packets;
+	struct sk_buff *skb;
+
+	/* Steal the current queue into our local one. */
+	__skb_queue_head_init(&packets);
+	spin_lock_bh(&peer->staged_packet_queue.lock);
+	skb_queue_splice_init(&peer->staged_packet_queue, &packets);
+	spin_unlock_bh(&peer->staged_packet_queue.lock);
+	if (unlikely(skb_queue_empty(&packets)))
+		return;
+
+	/* First we make sure we have a valid reference to a valid key. */
+	rcu_read_lock_bh();
+	keypair = wg_noise_keypair_get(
+		rcu_dereference_bh(peer->keypairs.current_keypair));
+	rcu_read_unlock_bh();
+	if (unlikely(!keypair))
+		goto out_nokey;
+	if (unlikely(!READ_ONCE(keypair->sending.is_valid)))
+		goto out_nokey;
+	if (unlikely(wg_birthdate_has_expired(keypair->sending.birthdate,
+					      REJECT_AFTER_TIME)))
+		goto out_invalid;
+
+	/* After we know we have a somewhat valid key, we now try to assign
+	 * nonces to all of the packets in the queue. If we can't assign nonces
+	 * for all of them, we just consider it a failure and wait for the next
+	 * handshake.
+	 */
+	skb_queue_walk(&packets, skb) {
+		/* 0 for no outer TOS: no leak. TODO: at some later point, we
+		 * might consider using flowi->tos as outer instead.
+		 */
+		PACKET_CB(skb)->ds = ip_tunnel_ecn_encap(0, ip_hdr(skb), skb);
+		PACKET_CB(skb)->nonce =
+				atomic64_inc_return(&keypair->sending_counter) - 1;
+		if (unlikely(PACKET_CB(skb)->nonce >= REJECT_AFTER_MESSAGES))
+			goto out_invalid;
+	}
+
+	packets.prev->next = NULL;
+	wg_peer_get(keypair->entry.peer);
+	PACKET_CB(packets.next)->keypair = keypair;
+	wg_packet_create_data(peer, packets.next);
+	return;
+
+out_invalid:
+	WRITE_ONCE(keypair->sending.is_valid, false);
+out_nokey:
+	wg_noise_keypair_put(keypair, false);
+
+	/* We orphan the packets if we're waiting on a handshake, so that they
+	 * don't block a socket's pool.
+	 */
+	skb_queue_walk(&packets, skb)
+		skb_orphan(skb);
+	/* Then we put them back on the top of the queue. We're not too
+	 * concerned about accidentally getting things a little out of order if
+	 * packets are being added really fast, because this queue is for before
+	 * packets can even be sent and it's small anyway.
+	 */
+	spin_lock_bh(&peer->staged_packet_queue.lock);
+	skb_queue_splice(&packets, &peer->staged_packet_queue);
+	spin_unlock_bh(&peer->staged_packet_queue.lock);
+
+	/* If we're exiting because there's something wrong with the key, it
+	 * means we should initiate a new handshake.
+	 */
+	wg_packet_send_queued_handshake_initiation(peer, false);
+}

linux-7.2.3/drivers/net/wireguard/socket.c

@@ -0,0 +1,436 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include "device.h"
+#include "peer.h"
+#include "socket.h"
+#include "queueing.h"
+#include "messages.h"
+
+#include <linux/ctype.h>
+#include <linux/net.h>
+#include <linux/if_vlan.h>
+#include <linux/if_ether.h>
+#include <linux/inetdevice.h>
+#include <net/udp_tunnel.h>
+#include <net/ipv6.h>
+
+static int send4(struct wg_device *wg, struct sk_buff *skb,
+		 struct endpoint *endpoint, u8 ds, struct dst_cache *cache)
+{
+	struct flowi4 fl = {
+		.saddr = endpoint->src4.s_addr,
+		.daddr = endpoint->addr4.sin_addr.s_addr,
+		.fl4_dport = endpoint->addr4.sin_port,
+		.flowi4_mark = wg->fwmark,
+		.flowi4_proto = IPPROTO_UDP
+	};
+	struct rtable *rt = NULL;
+	struct sock *sock;
+	int ret = 0;
+
+	skb_mark_not_on_list(skb);
+	skb->dev = wg->dev;
+	skb->mark = wg->fwmark;
+
+	rcu_read_lock_bh();
+	sock = rcu_dereference_bh(wg->sock4);
+
+	if (unlikely(!sock)) {
+		ret = -ENONET;
+		goto err;
+	}
+
+	fl.fl4_sport = inet_sk(sock)->inet_sport;
+
+	if (cache)
+		rt = dst_cache_get_ip4(cache, &fl.saddr);
+
+	if (!rt) {
+		security_sk_classify_flow(sock, flowi4_to_flowi_common(&fl));
+		if (unlikely(!inet_confirm_addr(sock_net(sock), NULL, 0,
+						fl.saddr, RT_SCOPE_HOST))) {
+			endpoint->src4.s_addr = 0;
+			endpoint->src_if4 = 0;
+			fl.saddr = 0;
+			if (cache)
+				dst_cache_reset(cache);
+		}
+		rt = ip_route_output_flow(sock_net(sock), &fl, sock);
+		if (unlikely(endpoint->src_if4 && ((IS_ERR(rt) &&
+			     PTR_ERR(rt) == -EINVAL) || (!IS_ERR(rt) &&
+			     rt->dst.dev->ifindex != endpoint->src_if4)))) {
+			endpoint->src4.s_addr = 0;
+			endpoint->src_if4 = 0;
+			fl.saddr = 0;
+			if (cache)
+				dst_cache_reset(cache);
+			if (!IS_ERR(rt))
+				ip_rt_put(rt);
+			rt = ip_route_output_flow(sock_net(sock), &fl, sock);
+		}
+		if (IS_ERR(rt)) {
+			ret = PTR_ERR(rt);
+			net_dbg_ratelimited("%s: No route to %pISpfsc, error %d\n",
+					    wg->dev->name, &endpoint->addr, ret);
+			goto err;
+		}
+		if (cache)
+			dst_cache_set_ip4(cache, &rt->dst, fl.saddr);
+	}
+
+	skb->ignore_df = 1;
+	udp_tunnel_xmit_skb(rt, sock, skb, fl.saddr, fl.daddr, ds,
+			    ip4_dst_hoplimit(&rt->dst), 0, fl.fl4_sport,
+			    fl.fl4_dport, false, false, 0);
+	goto out;
+
+err:
+	kfree_skb(skb);
+out:
+	rcu_read_unlock_bh();
+	return ret;
+}
+
+static int send6(struct wg_device *wg, struct sk_buff *skb,
+		 struct endpoint *endpoint, u8 ds, struct dst_cache *cache)
+{
+#if IS_ENABLED(CONFIG_IPV6)
+	struct flowi6 fl = {
+		.saddr = endpoint->src6,
+		.daddr = endpoint->addr6.sin6_addr,
+		.fl6_dport = endpoint->addr6.sin6_port,
+		.flowi6_mark = wg->fwmark,
+		.flowi6_oif = endpoint->addr6.sin6_scope_id,
+		.flowi6_proto = IPPROTO_UDP
+		/* TODO: addr->sin6_flowinfo */
+	};
+	struct dst_entry *dst = NULL;
+	struct sock *sock;
+	int ret = 0;
+
+	skb_mark_not_on_list(skb);
+	skb->dev = wg->dev;
+	skb->mark = wg->fwmark;
+
+	rcu_read_lock_bh();
+	sock = rcu_dereference_bh(wg->sock6);
+
+	if (unlikely(!sock)) {
+		ret = -ENONET;
+		goto err;
+	}
+
+	fl.fl6_sport = inet_sk(sock)->inet_sport;
+
+	if (cache)
+		dst = dst_cache_get_ip6(cache, &fl.saddr);
+
+	if (!dst) {
+		security_sk_classify_flow(sock, flowi6_to_flowi_common(&fl));
+		if (unlikely(!ipv6_addr_any(&fl.saddr) &&
+			     !ipv6_chk_addr(sock_net(sock), &fl.saddr, NULL, 0))) {
+			endpoint->src6 = fl.saddr = in6addr_any;
+			if (cache)
+				dst_cache_reset(cache);
+		}
+		dst = ip6_dst_lookup_flow(sock_net(sock), sock, &fl, NULL);
+		if (IS_ERR(dst)) {
+			ret = PTR_ERR(dst);
+			net_dbg_ratelimited("%s: No route to %pISpfsc, error %d\n",
+					    wg->dev->name, &endpoint->addr, ret);
+			goto err;
+		}
+		if (cache)
+			dst_cache_set_ip6(cache, dst, &fl.saddr);
+	}
+
+	skb->ignore_df = 1;
+	udp_tunnel6_xmit_skb(dst, sock, skb, skb->dev, &fl.saddr, &fl.daddr, ds,
+			     ip6_dst_hoplimit(dst), 0, fl.fl6_sport,
+			     fl.fl6_dport, false, 0);
+	goto out;
+
+err:
+	kfree_skb(skb);
+out:
+	rcu_read_unlock_bh();
+	return ret;
+#else
+	kfree_skb(skb);
+	return -EAFNOSUPPORT;
+#endif
+}
+
+int wg_socket_send_skb_to_peer(struct wg_peer *peer, struct sk_buff *skb, u8 ds)
+{
+	size_t skb_len = skb->len;
+	int ret = -EAFNOSUPPORT;
+
+	read_lock_bh(&peer->endpoint_lock);
+	if (peer->endpoint.addr.sa_family == AF_INET)
+		ret = send4(peer->device, skb, &peer->endpoint, ds,
+			    &peer->endpoint_cache);
+	else if (peer->endpoint.addr.sa_family == AF_INET6)
+		ret = send6(peer->device, skb, &peer->endpoint, ds,
+			    &peer->endpoint_cache);
+	else
+		dev_kfree_skb(skb);
+	if (likely(!ret))
+		peer->tx_bytes += skb_len;
+	read_unlock_bh(&peer->endpoint_lock);
+
+	return ret;
+}
+
+int wg_socket_send_buffer_to_peer(struct wg_peer *peer, void *buffer,
+				  size_t len, u8 ds)
+{
+	struct sk_buff *skb = alloc_skb(len + SKB_HEADER_LEN, GFP_ATOMIC);
+
+	if (unlikely(!skb))
+		return -ENOMEM;
+
+	skb_reserve(skb, SKB_HEADER_LEN);
+	skb_set_inner_network_header(skb, 0);
+	skb_put_data(skb, buffer, len);
+	return wg_socket_send_skb_to_peer(peer, skb, ds);
+}
+
+int wg_socket_send_buffer_as_reply_to_skb(struct wg_device *wg,
+					  struct sk_buff *in_skb, void *buffer,
+					  size_t len)
+{
+	int ret = 0;
+	struct sk_buff *skb;
+	struct endpoint endpoint;
+
+	if (unlikely(!in_skb))
+		return -EINVAL;
+	ret = wg_socket_endpoint_from_skb(&endpoint, in_skb);
+	if (unlikely(ret < 0))
+		return ret;
+
+	skb = alloc_skb(len + SKB_HEADER_LEN, GFP_ATOMIC);
+	if (unlikely(!skb))
+		return -ENOMEM;
+	skb_reserve(skb, SKB_HEADER_LEN);
+	skb_set_inner_network_header(skb, 0);
+	skb_put_data(skb, buffer, len);
+
+	if (endpoint.addr.sa_family == AF_INET)
+		ret = send4(wg, skb, &endpoint, 0, NULL);
+	else if (endpoint.addr.sa_family == AF_INET6)
+		ret = send6(wg, skb, &endpoint, 0, NULL);
+	/* No other possibilities if the endpoint is valid, which it is,
+	 * as we checked above.
+	 */
+
+	return ret;
+}
+
+int wg_socket_endpoint_from_skb(struct endpoint *endpoint,
+				const struct sk_buff *skb)
+{
+	memset(endpoint, 0, sizeof(*endpoint));
+	if (skb->protocol == htons(ETH_P_IP)) {
+		endpoint->addr4.sin_family = AF_INET;
+		endpoint->addr4.sin_port = udp_hdr(skb)->source;
+		endpoint->addr4.sin_addr.s_addr = ip_hdr(skb)->saddr;
+		endpoint->src4.s_addr = ip_hdr(skb)->daddr;
+		endpoint->src_if4 = skb->skb_iif;
+	} else if (IS_ENABLED(CONFIG_IPV6) && skb->protocol == htons(ETH_P_IPV6)) {
+		endpoint->addr6.sin6_family = AF_INET6;
+		endpoint->addr6.sin6_port = udp_hdr(skb)->source;
+		endpoint->addr6.sin6_addr = ipv6_hdr(skb)->saddr;
+		endpoint->addr6.sin6_scope_id = ipv6_iface_scope_id(
+			&ipv6_hdr(skb)->saddr, skb->skb_iif);
+		endpoint->src6 = ipv6_hdr(skb)->daddr;
+	} else {
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static bool endpoint_eq(const struct endpoint *a, const struct endpoint *b)
+{
+	return (a->addr.sa_family == AF_INET && b->addr.sa_family == AF_INET &&
+		a->addr4.sin_port == b->addr4.sin_port &&
+		a->addr4.sin_addr.s_addr == b->addr4.sin_addr.s_addr &&
+		a->src4.s_addr == b->src4.s_addr && a->src_if4 == b->src_if4) ||
+	       (a->addr.sa_family == AF_INET6 &&
+		b->addr.sa_family == AF_INET6 &&
+		a->addr6.sin6_port == b->addr6.sin6_port &&
+		ipv6_addr_equal(&a->addr6.sin6_addr, &b->addr6.sin6_addr) &&
+		a->addr6.sin6_scope_id == b->addr6.sin6_scope_id &&
+		ipv6_addr_equal(&a->src6, &b->src6)) ||
+	       unlikely(!a->addr.sa_family && !b->addr.sa_family);
+}
+
+void wg_socket_set_peer_endpoint(struct wg_peer *peer,
+				 const struct endpoint *endpoint)
+{
+	/* First we check unlocked, in order to optimize, since it's pretty rare
+	 * that an endpoint will change. If we happen to be mid-write, and two
+	 * CPUs wind up writing the same thing or something slightly different,
+	 * it doesn't really matter much either.
+	 */
+	if (endpoint_eq(endpoint, &peer->endpoint))
+		return;
+	write_lock_bh(&peer->endpoint_lock);
+	if (endpoint->addr.sa_family == AF_INET) {
+		peer->endpoint.addr4 = endpoint->addr4;
+		peer->endpoint.src4 = endpoint->src4;
+		peer->endpoint.src_if4 = endpoint->src_if4;
+	} else if (IS_ENABLED(CONFIG_IPV6) && endpoint->addr.sa_family == AF_INET6) {
+		peer->endpoint.addr6 = endpoint->addr6;
+		peer->endpoint.src6 = endpoint->src6;
+	} else {
+		goto out;
+	}
+	dst_cache_reset(&peer->endpoint_cache);
+out:
+	write_unlock_bh(&peer->endpoint_lock);
+}
+
+void wg_socket_set_peer_endpoint_from_skb(struct wg_peer *peer,
+					  const struct sk_buff *skb)
+{
+	struct endpoint endpoint;
+
+	if (!wg_socket_endpoint_from_skb(&endpoint, skb))
+		wg_socket_set_peer_endpoint(peer, &endpoint);
+}
+
+void wg_socket_clear_peer_endpoint_src(struct wg_peer *peer)
+{
+	write_lock_bh(&peer->endpoint_lock);
+	memset(&peer->endpoint.src6, 0, sizeof(peer->endpoint.src6));
+	dst_cache_reset_now(&peer->endpoint_cache);
+	write_unlock_bh(&peer->endpoint_lock);
+}
+
+static int wg_receive(struct sock *sk, struct sk_buff *skb)
+{
+	struct wg_device *wg;
+
+	if (unlikely(!sk))
+		goto err;
+	wg = sk->sk_user_data;
+	if (unlikely(!wg))
+		goto err;
+	skb_mark_not_on_list(skb);
+	wg_packet_receive(wg, skb);
+	return 0;
+
+err:
+	kfree_skb(skb);
+	return 0;
+}
+
+static void sock_free(struct sock *sock)
+{
+	if (unlikely(!sock))
+		return;
+	sk_clear_memalloc(sock);
+	udp_tunnel_sock_release(sock);
+}
+
+static void set_sock_opts(struct socket *sock)
+{
+	sock->sk->sk_allocation = GFP_ATOMIC;
+	sock->sk->sk_sndbuf = INT_MAX;
+	sk_set_memalloc(sock->sk);
+}
+
+int wg_socket_init(struct wg_device *wg, u16 port)
+{
+	struct net *net;
+	int ret;
+	struct udp_tunnel_sock_cfg cfg = {
+		.sk_user_data = wg,
+		.encap_type = 1,
+		.encap_rcv = wg_receive
+	};
+	struct socket *new4 = NULL, *new6 = NULL;
+	struct udp_port_cfg port4 = {
+		.family = AF_INET,
+		.local_ip.s_addr = htonl(INADDR_ANY),
+		.local_udp_port = htons(port),
+		.use_udp_checksums = true
+	};
+#if IS_ENABLED(CONFIG_IPV6)
+	int retries = 0;
+	struct udp_port_cfg port6 = {
+		.family = AF_INET6,
+		.local_ip6 = IN6ADDR_ANY_INIT,
+		.use_udp6_tx_checksums = true,
+		.use_udp6_rx_checksums = true,
+		.ipv6_v6only = true
+	};
+#endif
+
+	rcu_read_lock();
+	net = rcu_dereference(wg->creating_net);
+	net = net ? maybe_get_net(net) : NULL;
+	rcu_read_unlock();
+	if (unlikely(!net))
+		return -ENONET;
+
+#if IS_ENABLED(CONFIG_IPV6)
+retry:
+#endif
+
+	ret = udp_sock_create(net, &port4, &new4);
+	if (ret < 0) {
+		pr_err("%s: Could not create IPv4 socket\n", wg->dev->name);
+		goto out;
+	}
+	set_sock_opts(new4);
+	setup_udp_tunnel_sock(net, new4->sk, &cfg);
+
+#if IS_ENABLED(CONFIG_IPV6)
+	if (ipv6_mod_enabled()) {
+		port6.local_udp_port = inet_sk(new4->sk)->inet_sport;
+		ret = udp_sock_create(net, &port6, &new6);
+		if (ret < 0) {
+			udp_tunnel_sock_release(new4->sk);
+			if (ret == -EADDRINUSE && !port && retries++ < 100)
+				goto retry;
+			pr_err("%s: Could not create IPv6 socket\n",
+			       wg->dev->name);
+			goto out;
+		}
+		set_sock_opts(new6);
+		setup_udp_tunnel_sock(net, new6->sk, &cfg);
+	}
+#endif
+
+	wg_socket_reinit(wg, new4->sk, new6 ? new6->sk : NULL);
+	ret = 0;
+out:
+	put_net(net);
+	return ret;
+}
+
+void wg_socket_reinit(struct wg_device *wg, struct sock *new4,
+		      struct sock *new6)
+{
+	struct sock *old4, *old6;
+
+	mutex_lock(&wg->socket_update_lock);
+	old4 = rcu_dereference_protected(wg->sock4,
+				lockdep_is_held(&wg->socket_update_lock));
+	old6 = rcu_dereference_protected(wg->sock6,
+				lockdep_is_held(&wg->socket_update_lock));
+	rcu_assign_pointer(wg->sock4, new4);
+	rcu_assign_pointer(wg->sock6, new6);
+	if (new4)
+		wg->incoming_port = ntohs(inet_sk(new4)->inet_sport);
+	mutex_unlock(&wg->socket_update_lock);
+	synchronize_net();
+	sock_free(old4);
+	sock_free(old6);
+}

linux-7.2.3/drivers/net/wireguard/socket.h

@@ -0,0 +1,44 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#ifndef _WG_SOCKET_H
+#define _WG_SOCKET_H
+
+#include <linux/netdevice.h>
+#include <linux/udp.h>
+#include <linux/if_vlan.h>
+#include <linux/if_ether.h>
+
+int wg_socket_init(struct wg_device *wg, u16 port);
+void wg_socket_reinit(struct wg_device *wg, struct sock *new4,
+		      struct sock *new6);
+int wg_socket_send_buffer_to_peer(struct wg_peer *peer, void *data,
+				  size_t len, u8 ds);
+int wg_socket_send_skb_to_peer(struct wg_peer *peer, struct sk_buff *skb,
+			       u8 ds);
+int wg_socket_send_buffer_as_reply_to_skb(struct wg_device *wg,
+					  struct sk_buff *in_skb,
+					  void *out_buffer, size_t len);
+
+int wg_socket_endpoint_from_skb(struct endpoint *endpoint,
+				const struct sk_buff *skb);
+void wg_socket_set_peer_endpoint(struct wg_peer *peer,
+				 const struct endpoint *endpoint);
+void wg_socket_set_peer_endpoint_from_skb(struct wg_peer *peer,
+					  const struct sk_buff *skb);
+void wg_socket_clear_peer_endpoint_src(struct wg_peer *peer);
+
+#if defined(CONFIG_DYNAMIC_DEBUG) || defined(DEBUG)
+#define net_dbg_skb_ratelimited(fmt, dev, skb, ...) do {                       \
+		struct endpoint __endpoint;                                    \
+		wg_socket_endpoint_from_skb(&__endpoint, skb);                 \
+		net_dbg_ratelimited(fmt, dev, &__endpoint.addr,                \
+				    ##__VA_ARGS__);                            \
+	} while (0)
+#else
+#define net_dbg_skb_ratelimited(fmt, skb, ...)
+#endif
+
+#endif /* _WG_SOCKET_H */

linux-7.2.3/drivers/net/wireguard/timers.c

@@ -0,0 +1,246 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#include "timers.h"
+#include "device.h"
+#include "peer.h"
+#include "queueing.h"
+#include "socket.h"
+
+/*
+ * - Timer for retransmitting the handshake if we don't hear back after
+ * `REKEY_TIMEOUT + jitter` ms.
+ *
+ * - Timer for sending empty packet if we have received a packet but after have
+ * not sent one for `KEEPALIVE_TIMEOUT` ms.
+ *
+ * - Timer for initiating new handshake if we have sent a packet but after have
+ * not received one (even empty) for `(KEEPALIVE_TIMEOUT + REKEY_TIMEOUT) +
+ * jitter` ms.
+ *
+ * - Timer for zeroing out all ephemeral keys after `(REJECT_AFTER_TIME * 3)` ms
+ * if no new keys have been received.
+ *
+ * - Timer for, if enabled, sending an empty authenticated packet every user-
+ * specified seconds.
+ */
+
+static inline void mod_peer_timer(struct wg_peer *peer,
+				  struct timer_list *timer,
+				  unsigned long expires)
+{
+	rcu_read_lock_bh();
+	if (likely(netif_running(peer->device->dev) &&
+		   !READ_ONCE(peer->is_dead)))
+		mod_timer(timer, expires);
+	rcu_read_unlock_bh();
+}
+
+static void wg_expired_retransmit_handshake(struct timer_list *timer)
+{
+	struct wg_peer *peer = timer_container_of(peer, timer,
+						  timer_retransmit_handshake);
+
+	if (peer->timer_handshake_attempts > MAX_TIMER_HANDSHAKES) {
+		pr_debug("%s: Handshake for peer %llu (%pISpfsc) did not complete after %d attempts, giving up\n",
+			 peer->device->dev->name, peer->internal_id,
+			 &peer->endpoint.addr, (int)MAX_TIMER_HANDSHAKES + 2);
+
+		timer_delete(&peer->timer_send_keepalive);
+		/* We drop all packets without a keypair and don't try again,
+		 * if we try unsuccessfully for too long to make a handshake.
+		 */
+		wg_packet_purge_staged_packets(peer);
+
+		/* We set a timer for destroying any residue that might be left
+		 * of a partial exchange.
+		 */
+		if (!timer_pending(&peer->timer_zero_key_material))
+			mod_peer_timer(peer, &peer->timer_zero_key_material,
+				       jiffies + REJECT_AFTER_TIME * 3 * HZ);
+	} else {
+		++peer->timer_handshake_attempts;
+		pr_debug("%s: Handshake for peer %llu (%pISpfsc) did not complete after %d seconds, retrying (try %d)\n",
+			 peer->device->dev->name, peer->internal_id,
+			 &peer->endpoint.addr, (int)REKEY_TIMEOUT,
+			 peer->timer_handshake_attempts + 1);
+
+		/* We clear the endpoint address src address, in case this is
+		 * the cause of trouble.
+		 */
+		wg_socket_clear_peer_endpoint_src(peer);
+
+		wg_packet_send_queued_handshake_initiation(peer, true);
+	}
+}
+
+static void wg_expired_send_keepalive(struct timer_list *timer)
+{
+	struct wg_peer *peer = timer_container_of(peer, timer,
+						  timer_send_keepalive);
+
+	wg_packet_send_keepalive(peer);
+	if (peer->timer_need_another_keepalive) {
+		peer->timer_need_another_keepalive = false;
+		mod_peer_timer(peer, &peer->timer_send_keepalive,
+			       jiffies + KEEPALIVE_TIMEOUT * HZ);
+	}
+}
+
+static void wg_expired_new_handshake(struct timer_list *timer)
+{
+	struct wg_peer *peer = timer_container_of(peer, timer,
+						  timer_new_handshake);
+
+	pr_debug("%s: Retrying handshake with peer %llu (%pISpfsc) because we stopped hearing back after %d seconds\n",
+		 peer->device->dev->name, peer->internal_id,
+		 &peer->endpoint.addr, (int)(KEEPALIVE_TIMEOUT + REKEY_TIMEOUT));
+	/* We clear the endpoint address src address, in case this is the cause
+	 * of trouble.
+	 */
+	wg_socket_clear_peer_endpoint_src(peer);
+	wg_packet_send_queued_handshake_initiation(peer, false);
+}
+
+static void wg_expired_zero_key_material(struct timer_list *timer)
+{
+	struct wg_peer *peer = timer_container_of(peer, timer,
+						  timer_zero_key_material);
+
+	rcu_read_lock_bh();
+	if (!READ_ONCE(peer->is_dead)) {
+		wg_peer_get(peer);
+		if (!queue_work(peer->device->handshake_send_wq,
+				&peer->clear_peer_work))
+			/* If the work was already on the queue, we want to drop
+			 * the extra reference.
+			 */
+			wg_peer_put(peer);
+	}
+	rcu_read_unlock_bh();
+}
+
+static void wg_queued_expired_zero_key_material(struct work_struct *work)
+{
+	struct wg_peer *peer = container_of(work, struct wg_peer,
+					    clear_peer_work);
+
+	pr_debug("%s: Zeroing out all keys for peer %llu (%pISpfsc), since we haven't received a new one in %d seconds\n",
+		 peer->device->dev->name, peer->internal_id,
+		 &peer->endpoint.addr, (int)REJECT_AFTER_TIME * 3);
+	wg_noise_handshake_clear(&peer->handshake);
+	wg_noise_keypairs_clear(&peer->keypairs);
+	wg_peer_put(peer);
+}
+
+static void wg_expired_send_persistent_keepalive(struct timer_list *timer)
+{
+	struct wg_peer *peer = timer_container_of(peer, timer,
+						  timer_persistent_keepalive);
+
+	if (likely(peer->persistent_keepalive_interval))
+		wg_packet_send_keepalive(peer);
+}
+
+/* Should be called after an authenticated data packet is sent. */
+void wg_timers_data_sent(struct wg_peer *peer)
+{
+	if (!timer_pending(&peer->timer_new_handshake))
+		mod_peer_timer(peer, &peer->timer_new_handshake,
+			jiffies + (KEEPALIVE_TIMEOUT + REKEY_TIMEOUT) * HZ +
+			get_random_u32_below(REKEY_TIMEOUT_JITTER_MAX_JIFFIES));
+}
+
+/* Should be called after an authenticated data packet is received. */
+void wg_timers_data_received(struct wg_peer *peer)
+{
+	if (likely(netif_running(peer->device->dev))) {
+		if (!timer_pending(&peer->timer_send_keepalive))
+			mod_peer_timer(peer, &peer->timer_send_keepalive,
+				       jiffies + KEEPALIVE_TIMEOUT * HZ);
+		else
+			peer->timer_need_another_keepalive = true;
+	}
+}
+
+/* Should be called after any type of authenticated packet is sent, whether
+ * keepalive, data, or handshake.
+ */
+void wg_timers_any_authenticated_packet_sent(struct wg_peer *peer)
+{
+	timer_delete(&peer->timer_send_keepalive);
+}
+
+/* Should be called after any type of authenticated packet is received, whether
+ * keepalive, data, or handshake.
+ */
+void wg_timers_any_authenticated_packet_received(struct wg_peer *peer)
+{
+	timer_delete(&peer->timer_new_handshake);
+}
+
+/* Should be called after a handshake initiation message is sent. */
+void wg_timers_handshake_initiated(struct wg_peer *peer)
+{
+	mod_peer_timer(peer, &peer->timer_retransmit_handshake,
+		       jiffies + REKEY_TIMEOUT * HZ +
+		       get_random_u32_below(REKEY_TIMEOUT_JITTER_MAX_JIFFIES));
+}
+
+/* Should be called after a handshake response message is received and processed
+ * or when getting key confirmation via the first data message.
+ */
+void wg_timers_handshake_complete(struct wg_peer *peer)
+{
+	timer_delete(&peer->timer_retransmit_handshake);
+	peer->timer_handshake_attempts = 0;
+	peer->sent_lastminute_handshake = false;
+	ktime_get_real_ts64(&peer->walltime_last_handshake);
+}
+
+/* Should be called after an ephemeral key is created, which is before sending a
+ * handshake response or after receiving a handshake response.
+ */
+void wg_timers_session_derived(struct wg_peer *peer)
+{
+	mod_peer_timer(peer, &peer->timer_zero_key_material,
+		       jiffies + REJECT_AFTER_TIME * 3 * HZ);
+}
+
+/* Should be called before a packet with authentication, whether
+ * keepalive, data, or handshakem is sent, or after one is received.
+ */
+void wg_timers_any_authenticated_packet_traversal(struct wg_peer *peer)
+{
+	if (peer->persistent_keepalive_interval)
+		mod_peer_timer(peer, &peer->timer_persistent_keepalive,
+			jiffies + peer->persistent_keepalive_interval * HZ);
+}
+
+void wg_timers_init(struct wg_peer *peer)
+{
+	timer_setup(&peer->timer_retransmit_handshake,
+		    wg_expired_retransmit_handshake, 0);
+	timer_setup(&peer->timer_send_keepalive, wg_expired_send_keepalive, 0);
+	timer_setup(&peer->timer_new_handshake, wg_expired_new_handshake, 0);
+	timer_setup(&peer->timer_zero_key_material,
+		    wg_expired_zero_key_material, 0);
+	timer_setup(&peer->timer_persistent_keepalive,
+		    wg_expired_send_persistent_keepalive, 0);
+	INIT_WORK(&peer->clear_peer_work, wg_queued_expired_zero_key_material);
+	peer->timer_handshake_attempts = 0;
+	peer->sent_lastminute_handshake = false;
+	peer->timer_need_another_keepalive = false;
+}
+
+void wg_timers_stop(struct wg_peer *peer)
+{
+	timer_delete_sync(&peer->timer_retransmit_handshake);
+	timer_delete_sync(&peer->timer_send_keepalive);
+	timer_delete_sync(&peer->timer_new_handshake);
+	timer_delete_sync(&peer->timer_zero_key_material);
+	timer_delete_sync(&peer->timer_persistent_keepalive);
+	flush_work(&peer->clear_peer_work);
+}

linux-7.2.3/drivers/net/wireguard/timers.h

@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#ifndef _WG_TIMERS_H
+#define _WG_TIMERS_H
+
+#include <linux/ktime.h>
+
+struct wg_peer;
+
+void wg_timers_init(struct wg_peer *peer);
+void wg_timers_stop(struct wg_peer *peer);
+void wg_timers_data_sent(struct wg_peer *peer);
+void wg_timers_data_received(struct wg_peer *peer);
+void wg_timers_any_authenticated_packet_sent(struct wg_peer *peer);
+void wg_timers_any_authenticated_packet_received(struct wg_peer *peer);
+void wg_timers_handshake_initiated(struct wg_peer *peer);
+void wg_timers_handshake_complete(struct wg_peer *peer);
+void wg_timers_session_derived(struct wg_peer *peer);
+void wg_timers_any_authenticated_packet_traversal(struct wg_peer *peer);
+
+static inline bool wg_birthdate_has_expired(u64 birthday_nanoseconds,
+					    u64 expiration_seconds)
+{
+	return (s64)(birthday_nanoseconds + expiration_seconds * NSEC_PER_SEC)
+		<= (s64)ktime_get_coarse_boottime_ns();
+}
+
+#endif /* _WG_TIMERS_H */

linux-7.2.3/drivers/net/wireguard/version.h

@@ -0,0 +1 @@
+#define WIREGUARD_VERSION "1.0.0"