Resguardo inicial

linux-7.2.3/security/selinux/ss/avtab.c

@@ -0,0 +1,618 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Implementation of the access vector table type.
+ *
+ * Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
+ */
+
+/* Updated: Frank Mayer <mayerf@tresys.com> and
+ *          Karl MacMillan <kmacmillan@tresys.com>
+ *          Added conditional policy language extensions
+ *          Copyright (C) 2003 Tresys Technology, LLC
+ *
+ * Updated: Yuichi Nakamura <ynakam@hitachisoft.jp>
+ *          Tuned number of hash slots for avtab to reduce memory usage
+ */
+
+#include <linux/bitops.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include "avtab.h"
+#include "policydb.h"
+#include "hash.h"
+
+static struct kmem_cache *avtab_node_cachep __ro_after_init;
+static struct kmem_cache *avtab_xperms_cachep __ro_after_init;
+
+static inline u32 avtab_hash(const struct avtab_key *keyp, u32 mask)
+{
+	return av_hash((u32)keyp->target_class, (u32)keyp->target_type,
+		       (u32)keyp->source_type, mask);
+}
+
+static struct avtab_node *avtab_insert_node(struct avtab *h,
+					    struct avtab_node **dst,
+					    const struct avtab_key *key,
+					    const struct avtab_datum *datum)
+{
+	struct avtab_node *newnode;
+	struct avtab_extended_perms *xperms;
+	newnode = kmem_cache_zalloc(avtab_node_cachep, GFP_KERNEL);
+	if (newnode == NULL)
+		return NULL;
+	newnode->key = *key;
+
+	if (key->specified & AVTAB_XPERMS) {
+		xperms = kmem_cache_zalloc(avtab_xperms_cachep, GFP_KERNEL);
+		if (xperms == NULL) {
+			kmem_cache_free(avtab_node_cachep, newnode);
+			return NULL;
+		}
+		*xperms = *(datum->u.xperms);
+		newnode->datum.u.xperms = xperms;
+	} else {
+		newnode->datum.u.data = datum->u.data;
+	}
+
+	newnode->next = *dst;
+	*dst = newnode;
+
+	h->nel++;
+	return newnode;
+}
+
+static int avtab_node_cmp(const struct avtab_key *key1,
+			  const struct avtab_key *key2)
+{
+	u16 specified = key1->specified & ~(AVTAB_ENABLED | AVTAB_ENABLED_OLD);
+
+	if (key1->source_type == key2->source_type &&
+	    key1->target_type == key2->target_type &&
+	    key1->target_class == key2->target_class &&
+	    (specified & key2->specified))
+		return 0;
+	if (key1->source_type < key2->source_type)
+		return -1;
+	if (key1->source_type == key2->source_type &&
+	    key1->target_type < key2->target_type)
+		return -1;
+	if (key1->source_type == key2->source_type &&
+	    key1->target_type == key2->target_type &&
+	    key1->target_class < key2->target_class)
+		return -1;
+	return 1;
+}
+
+static int avtab_insert(struct avtab *h, const struct avtab_key *key,
+			const struct avtab_datum *datum)
+{
+	u32 hvalue;
+	struct avtab_node *prev, *cur, *newnode;
+	int cmp;
+
+	if (!h || !h->nslot || h->nel == U32_MAX)
+		return -EINVAL;
+
+	hvalue = avtab_hash(key, h->mask);
+	for (prev = NULL, cur = h->htable[hvalue]; cur;
+	     prev = cur, cur = cur->next) {
+		cmp = avtab_node_cmp(key, &cur->key);
+		/* extended perms may not be unique */
+		if (cmp == 0 && !(key->specified & AVTAB_XPERMS))
+			return -EEXIST;
+		if (cmp <= 0)
+			break;
+	}
+
+	newnode = avtab_insert_node(h, prev ? &prev->next : &h->htable[hvalue],
+				    key, datum);
+	if (!newnode)
+		return -ENOMEM;
+
+	return 0;
+}
+
+/* Unlike avtab_insert(), this function allow multiple insertions of the same
+ * key/specified mask into the table, as needed by the conditional avtab.
+ * It also returns a pointer to the node inserted.
+ */
+struct avtab_node *avtab_insert_nonunique(struct avtab *h,
+					  const struct avtab_key *key,
+					  const struct avtab_datum *datum)
+{
+	u32 hvalue;
+	struct avtab_node *prev, *cur;
+	int cmp;
+
+	if (!h || !h->nslot || h->nel == U32_MAX)
+		return NULL;
+	hvalue = avtab_hash(key, h->mask);
+	for (prev = NULL, cur = h->htable[hvalue]; cur;
+	     prev = cur, cur = cur->next) {
+		cmp = avtab_node_cmp(key, &cur->key);
+		if (cmp <= 0)
+			break;
+	}
+	return avtab_insert_node(h, prev ? &prev->next : &h->htable[hvalue],
+				 key, datum);
+}
+
+/* This search function returns a node pointer, and can be used in
+ * conjunction with avtab_search_next_node()
+ */
+struct avtab_node *avtab_search_node(struct avtab *h,
+				     const struct avtab_key *key)
+{
+	u32 hvalue;
+	struct avtab_node *cur;
+	int cmp;
+
+	if (!h || !h->nslot)
+		return NULL;
+
+	hvalue = avtab_hash(key, h->mask);
+	for (cur = h->htable[hvalue]; cur; cur = cur->next) {
+		cmp = avtab_node_cmp(key, &cur->key);
+		if (cmp == 0)
+			return cur;
+		if (cmp < 0)
+			break;
+	}
+	return NULL;
+}
+
+struct avtab_node *avtab_search_node_next(struct avtab_node *node,
+					  u16 specified)
+{
+	struct avtab_key tmp_key;
+	struct avtab_node *cur;
+	int cmp;
+
+	if (!node)
+		return NULL;
+	tmp_key = node->key;
+	tmp_key.specified = specified;
+	for (cur = node->next; cur; cur = cur->next) {
+		cmp = avtab_node_cmp(&tmp_key, &cur->key);
+		if (cmp == 0)
+			return cur;
+		if (cmp < 0)
+			break;
+	}
+	return NULL;
+}
+
+void avtab_destroy(struct avtab *h)
+{
+	u32 i;
+	struct avtab_node *cur, *temp;
+
+	if (!h)
+		return;
+
+	for (i = 0; i < h->nslot; i++) {
+		cur = h->htable[i];
+		while (cur) {
+			temp = cur;
+			cur = cur->next;
+			if (temp->key.specified & AVTAB_XPERMS)
+				kmem_cache_free(avtab_xperms_cachep,
+						temp->datum.u.xperms);
+			kmem_cache_free(avtab_node_cachep, temp);
+		}
+	}
+	kvfree(h->htable);
+	h->htable = NULL;
+	h->nel = 0;
+	h->nslot = 0;
+	h->mask = 0;
+}
+
+void avtab_init(struct avtab *h)
+{
+	h->htable = NULL;
+	h->nel = 0;
+	h->nslot = 0;
+	h->mask = 0;
+}
+
+static int avtab_alloc_common(struct avtab *h, u32 nslot)
+{
+	if (!nslot)
+		return 0;
+
+	h->htable = kvcalloc(nslot, sizeof(void *), GFP_KERNEL);
+	if (!h->htable)
+		return -ENOMEM;
+
+	h->nslot = nslot;
+	h->mask = nslot - 1;
+	return 0;
+}
+
+int avtab_alloc(struct avtab *h, u32 nrules)
+{
+	int rc;
+	u32 nslot = 0;
+
+	if (nrules != 0) {
+		nslot = nrules > 3 ? rounddown_pow_of_two(nrules / 2) : 2;
+		if (nslot > MAX_AVTAB_HASH_BUCKETS)
+			nslot = MAX_AVTAB_HASH_BUCKETS;
+
+		rc = avtab_alloc_common(h, nslot);
+		if (rc)
+			return rc;
+	}
+
+	pr_debug("SELinux: %d avtab hash slots, %d rules.\n", nslot, nrules);
+	return 0;
+}
+
+int avtab_alloc_dup(struct avtab *new, const struct avtab *orig)
+{
+	return avtab_alloc_common(new, orig->nslot);
+}
+
+#ifdef CONFIG_SECURITY_SELINUX_DEBUG
+void avtab_hash_eval(struct avtab *h, const char *tag)
+{
+	u32 i, chain_len, slots_used, max_chain_len;
+	unsigned long long chain2_len_sum;
+	struct avtab_node *cur;
+
+	slots_used = 0;
+	max_chain_len = 0;
+	chain2_len_sum = 0;
+	for (i = 0; i < h->nslot; i++) {
+		cur = h->htable[i];
+		if (cur) {
+			slots_used++;
+			chain_len = 0;
+			while (cur) {
+				chain_len++;
+				cur = cur->next;
+			}
+
+			if (chain_len > max_chain_len)
+				max_chain_len = chain_len;
+			chain2_len_sum +=
+				(unsigned long long)chain_len * chain_len;
+		}
+	}
+
+	pr_debug("SELinux: %s:  %d entries and %d/%d buckets used, "
+		 "longest chain length %d, sum of chain length^2 %llu\n",
+		 tag, h->nel, slots_used, h->nslot, max_chain_len,
+		 chain2_len_sum);
+}
+#endif /* CONFIG_SECURITY_SELINUX_DEBUG */
+
+/* clang-format off */
+static const uint16_t spec_order[] = {
+	AVTAB_ALLOWED,
+	AVTAB_AUDITDENY,
+	AVTAB_AUDITALLOW,
+	AVTAB_TRANSITION,
+	AVTAB_CHANGE,
+	AVTAB_MEMBER,
+	AVTAB_XPERMS_ALLOWED,
+	AVTAB_XPERMS_AUDITALLOW,
+	AVTAB_XPERMS_DONTAUDIT
+};
+/* clang-format on */
+
+int avtab_read_item(struct avtab *a, struct policy_file *fp, struct policydb *pol,
+		    int (*insertf)(struct avtab *a, const struct avtab_key *k,
+				   const struct avtab_datum *d, void *p),
+		    void *p, bool conditional)
+{
+	__le16 buf16[4];
+	u16 enabled;
+	u32 items, items2, val, i;
+	struct avtab_key key;
+	struct avtab_datum datum;
+	struct avtab_extended_perms xperms;
+	__le32 buf32[ARRAY_SIZE(xperms.perms.p)];
+	int rc;
+	unsigned int vers = pol->policyvers;
+
+	memset(&key, 0, sizeof(struct avtab_key));
+	memset(&datum, 0, sizeof(struct avtab_datum));
+
+	if (vers < POLICYDB_VERSION_AVTAB) {
+		rc = next_entry(buf32, fp, sizeof(u32));
+		if (rc) {
+			pr_err("SELinux: avtab: truncated entry\n");
+			return rc;
+		}
+		/* Read five or more items: source type, target type,
+		 * target class, AV type, and at least one datum.
+		 */
+		items2 = le32_to_cpu(buf32[0]);
+		if (items2 < 5 || items2 > ARRAY_SIZE(buf32)) {
+			pr_err("SELinux: avtab: invalid item count\n");
+			return -EINVAL;
+		}
+		rc = next_entry(buf32, fp, sizeof(u32) * items2);
+		if (rc) {
+			pr_err("SELinux: avtab: truncated entry\n");
+			return rc;
+		}
+		items = 0;
+
+		val = le32_to_cpu(buf32[items++]);
+		key.source_type = (u16)val;
+		if (key.source_type != val) {
+			pr_err("SELinux: avtab: truncated source type\n");
+			return -EINVAL;
+		}
+		val = le32_to_cpu(buf32[items++]);
+		key.target_type = (u16)val;
+		if (key.target_type != val) {
+			pr_err("SELinux: avtab: truncated target type\n");
+			return -EINVAL;
+		}
+		val = le32_to_cpu(buf32[items++]);
+		key.target_class = (u16)val;
+		if (key.target_class != val) {
+			pr_err("SELinux: avtab: truncated target class\n");
+			return -EINVAL;
+		}
+
+		if (!policydb_type_isvalid(pol, key.source_type) ||
+		    !policydb_type_isvalid(pol, key.target_type) ||
+		    !policydb_class_isvalid(pol, key.target_class)) {
+			pr_err("SELinux: avtab: invalid type or class\n");
+			return -EINVAL;
+		}
+
+		val = le32_to_cpu(buf32[items++]);
+		enabled = (val & AVTAB_ENABLED_OLD) ? AVTAB_ENABLED : 0;
+
+		if (!(val & (AVTAB_AV | AVTAB_TYPE))) {
+			pr_err("SELinux: avtab: null entry\n");
+			return -EINVAL;
+		}
+		if ((val & AVTAB_AV) && (val & AVTAB_TYPE)) {
+			pr_err("SELinux: avtab: entry has both access vectors and types\n");
+			return -EINVAL;
+		}
+		if (val & AVTAB_XPERMS) {
+			pr_err("SELinux: avtab: entry has extended permissions\n");
+			return -EINVAL;
+		}
+
+		for (i = 0; i < ARRAY_SIZE(spec_order); i++) {
+			if (val & spec_order[i]) {
+				if (items >= items2) {
+					pr_err("SELinux: avtab: entry has too many items (%d/%d)\n",
+					       items + 1, items2);
+					return -EINVAL;
+				}
+				key.specified = spec_order[i] | enabled;
+				datum.u.data = le32_to_cpu(buf32[items++]);
+
+				if ((key.specified & AVTAB_TYPE) &&
+				    !policydb_simpletype_isvalid(pol, datum.u.data)) {
+					pr_err("SELinux: avtab: invalid type\n");
+					return -EINVAL;
+				}
+
+				rc = insertf(a, &key, &datum, p);
+				if (rc)
+					return rc;
+			}
+		}
+
+		if (items != items2) {
+			pr_err("SELinux: avtab: entry only had %d items, expected %d\n",
+			       items2, items);
+			return -EINVAL;
+		}
+		return 0;
+	}
+
+	rc = next_entry(buf16, fp, sizeof(u16) * 4);
+	if (rc) {
+		pr_err("SELinux: avtab: truncated entry\n");
+		return rc;
+	}
+
+	items = 0;
+	key.source_type = le16_to_cpu(buf16[items++]);
+	key.target_type = le16_to_cpu(buf16[items++]);
+	key.target_class = le16_to_cpu(buf16[items++]);
+	key.specified = le16_to_cpu(buf16[items++]);
+
+	if (!policydb_type_isvalid(pol, key.source_type) ||
+	    !policydb_type_isvalid(pol, key.target_type) ||
+	    !policydb_class_isvalid(pol, key.target_class)) {
+		pr_err("SELinux: avtab: invalid type or class\n");
+		return -EINVAL;
+	}
+
+	if (hweight16(key.specified & ~AVTAB_ENABLED) != 1) {
+		pr_err("SELinux:  avtab:  not exactly one specifier\n");
+		return -EINVAL;
+	}
+
+	if (key.specified & ~AVTAB_SPECIFIER_MASK) {
+		pr_err("SELinux:  avtab:  invalid specifier\n");
+		return -EINVAL;
+	}
+
+	if ((vers < POLICYDB_VERSION_XPERMS_IOCTL) &&
+	    (key.specified & AVTAB_XPERMS)) {
+		pr_err("SELinux:  avtab:  policy version %u does not "
+		       "support extended permissions rules and one "
+		       "was specified\n",
+		       vers);
+		return -EINVAL;
+	} else if ((vers < POLICYDB_VERSION_COND_XPERMS) &&
+		   (key.specified & AVTAB_XPERMS) && conditional) {
+		pr_err("SELinux:  avtab:  policy version %u does not "
+		       "support extended permissions rules in conditional "
+		       "policies and one was specified\n",
+		       vers);
+		return -EINVAL;
+	} else if (key.specified & AVTAB_XPERMS) {
+		memset(&xperms, 0, sizeof(struct avtab_extended_perms));
+		rc = next_entry(&xperms.specified, fp, sizeof(u8));
+		if (rc) {
+			pr_err("SELinux: avtab: truncated entry\n");
+			return rc;
+		}
+		if (!avtab_is_valid_xperm_specified(xperms.specified))
+			pr_warn_once_policyload(pol,
+						"SELinux: avtab: unsupported xperm specifier %#x\n",
+						xperms.specified);
+		rc = next_entry(&xperms.driver, fp, sizeof(u8));
+		if (rc) {
+			pr_err("SELinux: avtab: truncated entry\n");
+			return rc;
+		}
+		rc = next_entry(buf32, fp,
+				sizeof(u32) * ARRAY_SIZE(xperms.perms.p));
+		if (rc) {
+			pr_err("SELinux: avtab: truncated entry\n");
+			return rc;
+		}
+		for (i = 0; i < ARRAY_SIZE(xperms.perms.p); i++)
+			xperms.perms.p[i] = le32_to_cpu(buf32[i]);
+		datum.u.xperms = &xperms;
+	} else {
+		rc = next_entry(buf32, fp, sizeof(u32));
+		if (rc) {
+			pr_err("SELinux: avtab: truncated entry\n");
+			return rc;
+		}
+		datum.u.data = le32_to_cpu(*buf32);
+	}
+	if ((key.specified & AVTAB_TYPE) &&
+	    !policydb_simpletype_isvalid(pol, datum.u.data)) {
+		pr_err("SELinux: avtab: invalid type\n");
+		return -EINVAL;
+	}
+	return insertf(a, &key, &datum, p);
+}
+
+static int avtab_insertf(struct avtab *a, const struct avtab_key *k,
+			 const struct avtab_datum *d, void *p)
+{
+	return avtab_insert(a, k, d);
+}
+
+int avtab_read(struct avtab *a, struct policy_file *fp, struct policydb *pol)
+{
+	int rc;
+	__le32 buf[1];
+	u32 nel, i;
+
+	rc = next_entry(buf, fp, sizeof(u32));
+	if (rc < 0) {
+		pr_err("SELinux: avtab: truncated table\n");
+		goto bad;
+	}
+	nel = le32_to_cpu(buf[0]);
+	if (!nel) {
+		pr_err("SELinux: avtab: table is empty\n");
+		rc = -EINVAL;
+		goto bad;
+	}
+
+	/* avtab_read_item() reads at least 96 bytes for any valid entry */
+	rc = size_check(3 * sizeof(u32), nel, fp);
+	if (rc)
+		goto bad;
+
+	rc = avtab_alloc(a, nel);
+	if (rc)
+		goto bad;
+
+	for (i = 0; i < nel; i++) {
+		rc = avtab_read_item(a, fp, pol, avtab_insertf, NULL, false);
+		if (rc) {
+			if (rc == -ENOMEM)
+				pr_err("SELinux: avtab: out of memory\n");
+			else if (rc == -EEXIST)
+				pr_err("SELinux: avtab: duplicate entry\n");
+
+			goto bad;
+		}
+	}
+
+	rc = 0;
+out:
+	return rc;
+
+bad:
+	avtab_destroy(a);
+	goto out;
+}
+
+int avtab_write_item(struct policydb *p, const struct avtab_node *cur, struct policy_file *fp)
+{
+	__le16 buf16[4];
+	__le32 buf32[ARRAY_SIZE(cur->datum.u.xperms->perms.p)];
+	int rc;
+	unsigned int i;
+
+	buf16[0] = cpu_to_le16(cur->key.source_type);
+	buf16[1] = cpu_to_le16(cur->key.target_type);
+	buf16[2] = cpu_to_le16(cur->key.target_class);
+	buf16[3] = cpu_to_le16(cur->key.specified);
+	rc = put_entry(buf16, sizeof(u16), 4, fp);
+	if (rc)
+		return rc;
+
+	if (cur->key.specified & AVTAB_XPERMS) {
+		rc = put_entry(&cur->datum.u.xperms->specified, sizeof(u8), 1,
+			       fp);
+		if (rc)
+			return rc;
+		rc = put_entry(&cur->datum.u.xperms->driver, sizeof(u8), 1, fp);
+		if (rc)
+			return rc;
+		for (i = 0; i < ARRAY_SIZE(cur->datum.u.xperms->perms.p); i++)
+			buf32[i] = cpu_to_le32(cur->datum.u.xperms->perms.p[i]);
+		rc = put_entry(buf32, sizeof(u32),
+			       ARRAY_SIZE(cur->datum.u.xperms->perms.p), fp);
+	} else {
+		buf32[0] = cpu_to_le32(cur->datum.u.data);
+		rc = put_entry(buf32, sizeof(u32), 1, fp);
+	}
+	if (rc)
+		return rc;
+	return 0;
+}
+
+int avtab_write(struct policydb *p, struct avtab *a, struct policy_file *fp)
+{
+	u32 i;
+	int rc = 0;
+	struct avtab_node *cur;
+	__le32 buf[1];
+
+	buf[0] = cpu_to_le32(a->nel);
+	rc = put_entry(buf, sizeof(u32), 1, fp);
+	if (rc)
+		return rc;
+
+	for (i = 0; i < a->nslot; i++) {
+		for (cur = a->htable[i]; cur; cur = cur->next) {
+			rc = avtab_write_item(p, cur, fp);
+			if (rc)
+				return rc;
+		}
+	}
+
+	return rc;
+}
+
+void __init avtab_cache_init(void)
+{
+	avtab_node_cachep = KMEM_CACHE(avtab_node, SLAB_PANIC);
+	avtab_xperms_cachep = KMEM_CACHE(avtab_extended_perms, SLAB_PANIC);
+}

linux-7.2.3/security/selinux/ss/avtab.h

@@ -0,0 +1,141 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * An access vector table (avtab) is a hash table
+ * of access vectors and transition types indexed
+ * by a type pair and a class.  An access vector
+ * table is used to represent the type enforcement
+ * tables.
+ *
+ *  Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
+ */
+
+/* Updated: Frank Mayer <mayerf@tresys.com> and
+ *          Karl MacMillan <kmacmillan@tresys.com>
+ *          Added conditional policy language extensions
+ *          Copyright (C) 2003 Tresys Technology, LLC
+ *
+ * Updated: Yuichi Nakamura <ynakam@hitachisoft.jp>
+ *          Tuned number of hash slots for avtab to reduce memory usage
+ */
+
+#ifndef _SS_AVTAB_H_
+#define _SS_AVTAB_H_
+
+#include "security.h"
+
+struct avtab_key {
+	u16 source_type; /* source type */
+	u16 target_type; /* target type */
+	u16 target_class; /* target object class */
+#define AVTAB_ALLOWED	 0x0001
+#define AVTAB_AUDITALLOW 0x0002
+#define AVTAB_AUDITDENY	 0x0004
+#define AVTAB_AV	 (AVTAB_ALLOWED | AVTAB_AUDITALLOW | AVTAB_AUDITDENY)
+#define AVTAB_TRANSITION 0x0010
+#define AVTAB_MEMBER	 0x0020
+#define AVTAB_CHANGE	 0x0040
+#define AVTAB_TYPE	 (AVTAB_TRANSITION | AVTAB_MEMBER | AVTAB_CHANGE)
+/* extended permissions */
+#define AVTAB_XPERMS_ALLOWED	0x0100
+#define AVTAB_XPERMS_AUDITALLOW 0x0200
+#define AVTAB_XPERMS_DONTAUDIT	0x0400
+#define AVTAB_XPERMS                                      \
+	(AVTAB_XPERMS_ALLOWED | AVTAB_XPERMS_AUDITALLOW | \
+	 AVTAB_XPERMS_DONTAUDIT)
+#define AVTAB_ENABLED_OLD 0x80000000 /* reserved for used in cond_avtab */
+#define AVTAB_ENABLED	  0x8000 /* reserved for used in cond_avtab */
+#define AVTAB_SPECIFIER_MASK (AVTAB_AV | AVTAB_TYPE | AVTAB_XPERMS | AVTAB_ENABLED)
+	u16 specified; /* what field is specified */
+};
+
+/*
+ * For operations that require more than the 32 permissions provided by the avc
+ * extended permissions may be used to provide 256 bits of permissions.
+ */
+struct avtab_extended_perms {
+/* These are not flags. All 256 values may be used */
+#define AVTAB_XPERMS_IOCTLFUNCTION	0x01
+#define AVTAB_XPERMS_IOCTLDRIVER	0x02
+#define AVTAB_XPERMS_NLMSG		0x03
+	/* extension of the avtab_key specified */
+	u8 specified; /* ioctl, netfilter, ... */
+	/*
+	 * if 256 bits is not adequate as is often the case with ioctls, then
+	 * multiple extended perms may be used and the driver field
+	 * specifies which permissions are included.
+	 */
+	u8 driver;
+	/* 256 bits of permissions */
+	struct extended_perms_data perms;
+};
+
+static inline bool avtab_is_valid_xperm_specified(u8 specified)
+{
+	switch (specified) {
+	case AVTAB_XPERMS_IOCTLFUNCTION:
+	case AVTAB_XPERMS_IOCTLDRIVER:
+	case AVTAB_XPERMS_NLMSG:
+		return true;
+	default:
+		return false;
+	}
+}
+
+struct avtab_datum {
+	union {
+		u32 data; /* access vector or type value */
+		struct avtab_extended_perms *xperms;
+	} u;
+};
+
+struct avtab_node {
+	struct avtab_key key;
+	struct avtab_datum datum;
+	struct avtab_node *next;
+};
+
+struct avtab {
+	struct avtab_node **htable;
+	u32 nel; /* number of elements */
+	u32 nslot; /* number of hash slots */
+	u32 mask; /* mask to compute hash func */
+};
+
+void avtab_init(struct avtab *h);
+int avtab_alloc(struct avtab *h, u32 nrules);
+int avtab_alloc_dup(struct avtab *new, const struct avtab *orig);
+void avtab_destroy(struct avtab *h);
+
+#define MAX_AVTAB_HASH_BITS    16
+#define MAX_AVTAB_HASH_BUCKETS (1 << MAX_AVTAB_HASH_BITS)
+
+#ifdef CONFIG_SECURITY_SELINUX_DEBUG
+void avtab_hash_eval(struct avtab *h, const char *tag);
+#else
+static inline void avtab_hash_eval(struct avtab *h, const char *tag)
+{
+}
+#endif
+
+struct policydb;
+struct policy_file;
+int avtab_read_item(struct avtab *a, struct policy_file *fp, struct policydb *pol,
+		    int (*insert)(struct avtab *a, const struct avtab_key *k,
+				  const struct avtab_datum *d, void *p),
+		    void *p, bool conditional);
+
+int avtab_read(struct avtab *a, struct policy_file *fp, struct policydb *pol);
+int avtab_write_item(struct policydb *p, const struct avtab_node *cur,
+		     struct policy_file *fp);
+int avtab_write(struct policydb *p, struct avtab *a, struct policy_file *fp);
+
+struct avtab_node *avtab_insert_nonunique(struct avtab *h,
+					  const struct avtab_key *key,
+					  const struct avtab_datum *datum);
+
+struct avtab_node *avtab_search_node(struct avtab *h,
+				     const struct avtab_key *key);
+struct avtab_node *avtab_search_node_next(struct avtab_node *node,
+					  u16 specified);
+
+#endif /* _SS_AVTAB_H_ */

linux-7.2.3/security/selinux/ss/conditional.c

@@ -0,0 +1,765 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Authors: Karl MacMillan <kmacmillan@tresys.com>
+ *	    Frank Mayer <mayerf@tresys.com>
+ *          Copyright (C) 2003 - 2004 Tresys Technology, LLC
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+
+#include "security.h"
+#include "conditional.h"
+#include "policydb.h"
+#include "services.h"
+
+/*
+ * cond_evaluate_expr evaluates a conditional expr
+ * in reverse polish notation. It returns true (1), false (0),
+ * or undefined (-1). Undefined occurs when the expression
+ * exceeds the stack depth of COND_EXPR_MAXDEPTH.
+ */
+static int cond_evaluate_expr(struct policydb *p, struct cond_expr *expr)
+{
+	u32 i;
+	int s[COND_EXPR_MAXDEPTH];
+	int sp = -1;
+
+	if (expr->len == 0)
+		return -1;
+
+	for (i = 0; i < expr->len; i++) {
+		struct cond_expr_node *node = &expr->nodes[i];
+
+		switch (node->expr_type) {
+		case COND_BOOL:
+			if (sp == (COND_EXPR_MAXDEPTH - 1))
+				return -1;
+			sp++;
+			s[sp] = p->bool_val_to_struct[node->boolean - 1]->state;
+			break;
+		case COND_NOT:
+			if (sp < 0)
+				return -1;
+			s[sp] = !s[sp];
+			break;
+		case COND_OR:
+			if (sp < 1)
+				return -1;
+			sp--;
+			s[sp] |= s[sp + 1];
+			break;
+		case COND_AND:
+			if (sp < 1)
+				return -1;
+			sp--;
+			s[sp] &= s[sp + 1];
+			break;
+		case COND_XOR:
+			if (sp < 1)
+				return -1;
+			sp--;
+			s[sp] ^= s[sp + 1];
+			break;
+		case COND_EQ:
+			if (sp < 1)
+				return -1;
+			sp--;
+			s[sp] = (s[sp] == s[sp + 1]);
+			break;
+		case COND_NEQ:
+			if (sp < 1)
+				return -1;
+			sp--;
+			s[sp] = (s[sp] != s[sp + 1]);
+			break;
+		default:
+			return -1;
+		}
+	}
+	return s[0];
+}
+
+/*
+ * evaluate_cond_node evaluates the conditional stored in
+ * a struct cond_node and if the result is different than the
+ * current state of the node it sets the rules in the true/false
+ * list appropriately. If the result of the expression is undefined
+ * all of the rules are disabled for safety.
+ */
+static void evaluate_cond_node(struct policydb *p, struct cond_node *node)
+{
+	struct avtab_node *avnode;
+	int new_state;
+	u32 i;
+
+	new_state = cond_evaluate_expr(p, &node->expr);
+	if (new_state != node->cur_state) {
+		node->cur_state = new_state;
+		if (new_state == -1)
+			pr_err("SELinux: expression result was undefined - disabling all rules.\n");
+		/* turn the rules on or off */
+		for (i = 0; i < node->true_list.len; i++) {
+			avnode = node->true_list.nodes[i];
+			if (new_state <= 0)
+				avnode->key.specified &= ~AVTAB_ENABLED;
+			else
+				avnode->key.specified |= AVTAB_ENABLED;
+		}
+
+		for (i = 0; i < node->false_list.len; i++) {
+			avnode = node->false_list.nodes[i];
+			/* -1 or 1 */
+			if (new_state)
+				avnode->key.specified &= ~AVTAB_ENABLED;
+			else
+				avnode->key.specified |= AVTAB_ENABLED;
+		}
+	}
+}
+
+void evaluate_cond_nodes(struct policydb *p)
+{
+	u32 i;
+
+	for (i = 0; i < p->cond_list_len; i++)
+		evaluate_cond_node(p, &p->cond_list[i]);
+}
+
+void cond_policydb_init(struct policydb *p)
+{
+	p->bool_val_to_struct = NULL;
+	p->cond_list = NULL;
+	p->cond_list_len = 0;
+
+	avtab_init(&p->te_cond_avtab);
+}
+
+static void cond_node_destroy(struct cond_node *node)
+{
+	kfree(node->expr.nodes);
+	/* the avtab_ptr_t nodes are destroyed by the avtab */
+	kfree(node->true_list.nodes);
+	kfree(node->false_list.nodes);
+}
+
+static void cond_list_destroy(struct policydb *p)
+{
+	u32 i;
+
+	for (i = 0; i < p->cond_list_len; i++)
+		cond_node_destroy(&p->cond_list[i]);
+	kfree(p->cond_list);
+	p->cond_list = NULL;
+	p->cond_list_len = 0;
+}
+
+void cond_policydb_destroy(struct policydb *p)
+{
+	kfree(p->bool_val_to_struct);
+	avtab_destroy(&p->te_cond_avtab);
+	cond_list_destroy(p);
+}
+
+int cond_init_bool_indexes(struct policydb *p)
+{
+	kfree(p->bool_val_to_struct);
+	p->bool_val_to_struct = kzalloc_objs(*p->bool_val_to_struct,
+					     p->p_bools.nprim);
+	if (!p->bool_val_to_struct)
+		return -ENOMEM;
+
+	avtab_hash_eval(&p->te_cond_avtab, "conditional_rules");
+
+	return 0;
+}
+
+int cond_destroy_bool(void *key, void *datum, void *p)
+{
+	kfree(key);
+	kfree(datum);
+	return 0;
+}
+
+int cond_index_bool(void *key, void *datum, void *datap)
+{
+	struct policydb *p;
+	struct cond_bool_datum *booldatum;
+
+	booldatum = datum;
+	p = datap;
+
+	if (!booldatum->value || booldatum->value > p->p_bools.nprim)
+		return -EINVAL;
+
+	p->sym_val_to_name[SYM_BOOLS][booldatum->value - 1] = key;
+	p->bool_val_to_struct[booldatum->value - 1] = booldatum;
+
+	return 0;
+}
+
+int cond_read_bool(struct policydb *p, struct symtab *s, struct policy_file *fp)
+{
+	char *key = NULL;
+	struct cond_bool_datum *booldatum;
+	__le32 buf[3];
+	u32 len, val;
+	int rc;
+
+	booldatum = kzalloc_obj(*booldatum);
+	if (!booldatum)
+		return -ENOMEM;
+
+	rc = next_entry(buf, fp, sizeof(buf));
+	if (rc)
+		goto err;
+
+	booldatum->value = le32_to_cpu(buf[0]);
+	val = le32_to_cpu(buf[1]);
+
+	rc = -EINVAL;
+	if (!val_is_boolean(val))
+		goto err;
+	booldatum->state = (int)val;
+
+	len = le32_to_cpu(buf[2]);
+
+	rc = str_read(&key, GFP_KERNEL, fp, len);
+	if (rc)
+		goto err;
+
+	rc = symtab_insert(s, key, booldatum);
+	if (rc)
+		goto err;
+
+	return 0;
+err:
+	pr_err("SELinux: conditional: failed to read boolean\n");
+	cond_destroy_bool(key, booldatum, NULL);
+	return rc;
+}
+
+struct cond_insertf_data {
+	struct policydb *p;
+	struct avtab_node **dst;
+	struct cond_av_list *other;
+};
+
+static int cond_insertf(struct avtab *a, const struct avtab_key *k,
+			const struct avtab_datum *d, void *ptr)
+{
+	struct cond_insertf_data *data = ptr;
+	struct policydb *p = data->p;
+	struct cond_av_list *other = data->other;
+	struct avtab_node *node_ptr;
+	u32 i;
+	bool found;
+
+	/*
+	 * For type rules we have to make certain there aren't any
+	 * conflicting rules by searching the te_avtab and the
+	 * cond_te_avtab.
+	 */
+	if (k->specified & AVTAB_TYPE) {
+		if (avtab_search_node(&p->te_avtab, k)) {
+			pr_err("SELinux: type rule already exists outside of a conditional.\n");
+			return -EINVAL;
+		}
+		/*
+		 * If we are reading the false list other will be a pointer to
+		 * the true list. We can have duplicate entries if there is only
+		 * 1 other entry and it is in our true list.
+		 *
+		 * If we are reading the true list (other == NULL) there shouldn't
+		 * be any other entries.
+		 */
+		if (other) {
+			node_ptr = avtab_search_node(&p->te_cond_avtab, k);
+			if (node_ptr) {
+				if (avtab_search_node_next(node_ptr,
+							   k->specified)) {
+					pr_err("SELinux: too many conflicting type rules.\n");
+					return -EINVAL;
+				}
+				found = false;
+				for (i = 0; i < other->len; i++) {
+					if (other->nodes[i] == node_ptr) {
+						found = true;
+						break;
+					}
+				}
+				if (!found) {
+					pr_err("SELinux: conflicting type rules.\n");
+					return -EINVAL;
+				}
+			}
+		} else {
+			if (avtab_search_node(&p->te_cond_avtab, k)) {
+				pr_err("SELinux: conflicting type rules when adding type rule for true.\n");
+				return -EINVAL;
+			}
+		}
+	}
+
+	node_ptr = avtab_insert_nonunique(&p->te_cond_avtab, k, d);
+	if (!node_ptr) {
+		pr_err("SELinux: could not insert rule.\n");
+		return -ENOMEM;
+	}
+
+	*data->dst = node_ptr;
+	return 0;
+}
+
+static int cond_read_av_list(struct policydb *p, struct policy_file *fp,
+			     struct cond_av_list *list,
+			     struct cond_av_list *other)
+{
+	int rc;
+	__le32 buf[1];
+	u32 i, len;
+	struct cond_insertf_data data;
+
+	rc = next_entry(buf, fp, sizeof(u32));
+	if (rc)
+		return rc;
+
+	len = le32_to_cpu(buf[0]);
+	if (len == 0)
+		return 0;
+
+	/* avtab_read_item() reads at least 96 bytes for any valid entry */
+	rc = size_check(3 * sizeof(u32), len, fp);
+	if (rc)
+		return rc;
+
+	list->nodes = kzalloc_objs(*list->nodes, len);
+	if (!list->nodes)
+		return -ENOMEM;
+
+	data.p = p;
+	data.other = other;
+	for (i = 0; i < len; i++) {
+		data.dst = &list->nodes[i];
+		rc = avtab_read_item(&p->te_cond_avtab, fp, p, cond_insertf,
+				     &data, true);
+		if (rc) {
+			kfree(list->nodes);
+			list->nodes = NULL;
+			return rc;
+		}
+	}
+
+	list->len = len;
+	return 0;
+}
+
+static int expr_node_isvalid(struct policydb *p, struct cond_expr_node *expr)
+{
+	if (expr->expr_type <= 0 || expr->expr_type > COND_LAST) {
+		pr_err("SELinux: conditional expressions uses unknown operator.\n");
+		return 0;
+	}
+
+	if (expr->expr_type == COND_BOOL &&
+	    (expr->boolean == 0 || expr->boolean > p->p_bools.nprim)) {
+		pr_err("SELinux: conditional expressions uses unknown bool.\n");
+		return 0;
+	}
+	return 1;
+}
+
+static int cond_read_node(struct policydb *p, struct cond_node *node, struct policy_file *fp)
+{
+	__le32 buf[2];
+	u32 i, len;
+	int rc;
+
+	rc = next_entry(buf, fp, sizeof(u32) * 2);
+	if (rc)
+		return rc;
+
+	node->cur_state = le32_to_cpu(buf[0]);
+
+	/* expr */
+	len = le32_to_cpu(buf[1]);
+
+	/* we will read 64 bytes per node */
+	rc = size_check(2 * sizeof(u32), len, fp);
+	if (rc)
+		return rc;
+
+	node->expr.nodes = kzalloc_objs(*node->expr.nodes, len);
+	if (!node->expr.nodes)
+		return -ENOMEM;
+
+	node->expr.len = len;
+
+	for (i = 0; i < len; i++) {
+		struct cond_expr_node *expr = &node->expr.nodes[i];
+
+		rc = next_entry(buf, fp, sizeof(u32) * 2);
+		if (rc)
+			return rc;
+
+		expr->expr_type = le32_to_cpu(buf[0]);
+		expr->boolean = le32_to_cpu(buf[1]);
+
+		if (!expr_node_isvalid(p, expr))
+			return -EINVAL;
+	}
+
+	rc = cond_read_av_list(p, fp, &node->true_list, NULL);
+	if (rc)
+		return rc;
+	return cond_read_av_list(p, fp, &node->false_list, &node->true_list);
+}
+
+int cond_read_list(struct policydb *p, struct policy_file *fp)
+{
+	__le32 buf[1];
+	u32 i, len;
+	int rc;
+
+	rc = next_entry(buf, fp, sizeof(buf));
+	if (rc)
+		return rc;
+
+	len = le32_to_cpu(buf[0]);
+
+	/* cond_read_node() reads at least 128 bytes for any valid node */
+	rc = size_check(4 * sizeof(u32), len, fp);
+	if (rc)
+		return rc;
+
+	p->cond_list = kzalloc_objs(*p->cond_list, len);
+	if (!p->cond_list)
+		return -ENOMEM;
+
+	rc = avtab_alloc(&(p->te_cond_avtab), p->te_avtab.nel);
+	if (rc)
+		goto err;
+
+	p->cond_list_len = len;
+
+	for (i = 0; i < len; i++) {
+		rc = cond_read_node(p, &p->cond_list[i], fp);
+		if (rc)
+			goto err;
+	}
+	return 0;
+err:
+	cond_list_destroy(p);
+	return rc;
+}
+
+int cond_write_bool(void *vkey, void *datum, void *ptr)
+{
+	char *key = vkey;
+	struct cond_bool_datum *booldatum = datum;
+	struct policy_data *pd = ptr;
+	struct policy_file *fp = pd->fp;
+	__le32 buf[3];
+	u32 len;
+	int rc;
+
+	len = strlen(key);
+	buf[0] = cpu_to_le32(booldatum->value);
+	buf[1] = cpu_to_le32(booldatum->state);
+	buf[2] = cpu_to_le32(len);
+	rc = put_entry(buf, sizeof(u32), 3, fp);
+	if (rc)
+		return rc;
+	rc = put_entry(key, 1, len, fp);
+	if (rc)
+		return rc;
+	return 0;
+}
+
+/*
+ * cond_write_cond_av_list doesn't write out the av_list nodes.
+ * Instead it writes out the key/value pairs from the avtab. This
+ * is necessary because there is no way to uniquely identifying rules
+ * in the avtab so it is not possible to associate individual rules
+ * in the avtab with a conditional without saving them as part of
+ * the conditional. This means that the avtab with the conditional
+ * rules will not be saved but will be rebuilt on policy load.
+ */
+static int cond_write_av_list(struct policydb *p, struct cond_av_list *list,
+			      struct policy_file *fp)
+{
+	__le32 buf[1];
+	u32 i;
+	int rc;
+
+	buf[0] = cpu_to_le32(list->len);
+	rc = put_entry(buf, sizeof(u32), 1, fp);
+	if (rc)
+		return rc;
+
+	for (i = 0; i < list->len; i++) {
+		rc = avtab_write_item(p, list->nodes[i], fp);
+		if (rc)
+			return rc;
+	}
+
+	return 0;
+}
+
+static int cond_write_node(struct policydb *p, struct cond_node *node,
+			   struct policy_file *fp)
+{
+	__le32 buf[2];
+	int rc;
+	u32 i;
+
+	buf[0] = cpu_to_le32(node->cur_state);
+	rc = put_entry(buf, sizeof(u32), 1, fp);
+	if (rc)
+		return rc;
+
+	buf[0] = cpu_to_le32(node->expr.len);
+	rc = put_entry(buf, sizeof(u32), 1, fp);
+	if (rc)
+		return rc;
+
+	for (i = 0; i < node->expr.len; i++) {
+		buf[0] = cpu_to_le32(node->expr.nodes[i].expr_type);
+		buf[1] = cpu_to_le32(node->expr.nodes[i].boolean);
+		rc = put_entry(buf, sizeof(u32), 2, fp);
+		if (rc)
+			return rc;
+	}
+
+	rc = cond_write_av_list(p, &node->true_list, fp);
+	if (rc)
+		return rc;
+	rc = cond_write_av_list(p, &node->false_list, fp);
+	if (rc)
+		return rc;
+
+	return 0;
+}
+
+int cond_write_list(struct policydb *p, struct policy_file *fp)
+{
+	u32 i;
+	__le32 buf[1];
+	int rc;
+
+	buf[0] = cpu_to_le32(p->cond_list_len);
+	rc = put_entry(buf, sizeof(u32), 1, fp);
+	if (rc)
+		return rc;
+
+	for (i = 0; i < p->cond_list_len; i++) {
+		rc = cond_write_node(p, &p->cond_list[i], fp);
+		if (rc)
+			return rc;
+	}
+
+	return 0;
+}
+
+void cond_compute_xperms(struct avtab *ctab, struct avtab_key *key,
+			 struct extended_perms_decision *xpermd)
+{
+	struct avtab_node *node;
+
+	if (!ctab || !key || !xpermd)
+		return;
+
+	for (node = avtab_search_node(ctab, key); node;
+	     node = avtab_search_node_next(node, key->specified)) {
+		if (node->key.specified & AVTAB_ENABLED)
+			services_compute_xperms_decision(xpermd, node);
+	}
+}
+/* Determine whether additional permissions are granted by the conditional
+ * av table, and if so, add them to the result
+ */
+void cond_compute_av(struct avtab *ctab, struct avtab_key *key,
+		     struct av_decision *avd, struct extended_perms *xperms)
+{
+	struct avtab_node *node;
+
+	if (!ctab || !key || !avd)
+		return;
+
+	for (node = avtab_search_node(ctab, key); node;
+	     node = avtab_search_node_next(node, key->specified)) {
+		if ((u16)(AVTAB_ALLOWED | AVTAB_ENABLED) ==
+		    (node->key.specified & (AVTAB_ALLOWED | AVTAB_ENABLED)))
+			avd->allowed |= node->datum.u.data;
+		if ((u16)(AVTAB_AUDITDENY | AVTAB_ENABLED) ==
+		    (node->key.specified & (AVTAB_AUDITDENY | AVTAB_ENABLED)))
+			/* Since a '0' in an auditdeny mask represents a
+			 * permission we do NOT want to audit (dontaudit), we use
+			 * the '&' operand to ensure that all '0's in the mask
+			 * are retained (much unlike the allow and auditallow cases).
+			 */
+			avd->auditdeny &= node->datum.u.data;
+		if ((u16)(AVTAB_AUDITALLOW | AVTAB_ENABLED) ==
+		    (node->key.specified & (AVTAB_AUDITALLOW | AVTAB_ENABLED)))
+			avd->auditallow |= node->datum.u.data;
+		if (xperms && (node->key.specified & AVTAB_ENABLED) &&
+		    (node->key.specified & AVTAB_XPERMS))
+			services_compute_xperms_drivers(xperms, node);
+	}
+}
+
+static int cond_dup_av_list(struct cond_av_list *new,
+			    const struct cond_av_list *orig,
+			    struct avtab *avtab)
+{
+	u32 i;
+
+	memset(new, 0, sizeof(*new));
+
+	new->nodes = kzalloc_objs(*new->nodes, orig->len);
+	if (!new->nodes)
+		return -ENOMEM;
+
+	for (i = 0; i < orig->len; i++) {
+		new->nodes[i] = avtab_insert_nonunique(
+			avtab, &orig->nodes[i]->key, &orig->nodes[i]->datum);
+		if (!new->nodes[i])
+			return -ENOMEM;
+		new->len++;
+	}
+
+	return 0;
+}
+
+static int duplicate_policydb_cond_list(struct policydb *newp,
+					const struct policydb *origp)
+{
+	int rc;
+	u32 i;
+
+	rc = avtab_alloc_dup(&newp->te_cond_avtab, &origp->te_cond_avtab);
+	if (rc)
+		return rc;
+
+	newp->cond_list_len = 0;
+	newp->cond_list = kzalloc_objs(*newp->cond_list, origp->cond_list_len);
+	if (!newp->cond_list)
+		goto error;
+
+	for (i = 0; i < origp->cond_list_len; i++) {
+		struct cond_node *newn = &newp->cond_list[i];
+		const struct cond_node *orign = &origp->cond_list[i];
+
+		newp->cond_list_len++;
+
+		newn->cur_state = orign->cur_state;
+		newn->expr.nodes =
+			kmemdup(orign->expr.nodes,
+				orign->expr.len * sizeof(*orign->expr.nodes),
+				GFP_KERNEL);
+		if (!newn->expr.nodes)
+			goto error;
+
+		newn->expr.len = orign->expr.len;
+
+		rc = cond_dup_av_list(&newn->true_list, &orign->true_list,
+				      &newp->te_cond_avtab);
+		if (rc)
+			goto error;
+
+		rc = cond_dup_av_list(&newn->false_list, &orign->false_list,
+				      &newp->te_cond_avtab);
+		if (rc)
+			goto error;
+	}
+
+	return 0;
+
+error:
+	avtab_destroy(&newp->te_cond_avtab);
+	cond_list_destroy(newp);
+	return -ENOMEM;
+}
+
+static int cond_bools_destroy(void *key, void *datum, void *args)
+{
+	/* key was not copied so no need to free here */
+	kfree(datum);
+	return 0;
+}
+
+static int cond_bools_copy(struct hashtab_node *new,
+			   const struct hashtab_node *orig, void *args)
+{
+	struct cond_bool_datum *datum;
+
+	datum = kmemdup(orig->datum, sizeof(struct cond_bool_datum),
+			GFP_KERNEL);
+	if (!datum)
+		return -ENOMEM;
+
+	new->key = orig->key; /* No need to copy, never modified */
+	new->datum = datum;
+	return 0;
+}
+
+static int cond_bools_index(void *key, void *datum, void *args)
+{
+	struct cond_bool_datum *booldatum, **cond_bool_array;
+
+	booldatum = datum;
+	cond_bool_array = args;
+	cond_bool_array[booldatum->value - 1] = booldatum;
+
+	return 0;
+}
+
+static int duplicate_policydb_bools(struct policydb *newdb,
+				    const struct policydb *orig)
+{
+	struct cond_bool_datum **cond_bool_array;
+	int rc;
+
+	cond_bool_array = kzalloc_objs(*orig->bool_val_to_struct,
+				       orig->p_bools.nprim);
+	if (!cond_bool_array)
+		return -ENOMEM;
+
+	rc = hashtab_duplicate(&newdb->p_bools.table, &orig->p_bools.table,
+			       cond_bools_copy, cond_bools_destroy, NULL);
+	if (rc) {
+		kfree(cond_bool_array);
+		return -ENOMEM;
+	}
+
+	hashtab_map(&newdb->p_bools.table, cond_bools_index, cond_bool_array);
+	newdb->bool_val_to_struct = cond_bool_array;
+
+	newdb->p_bools.nprim = orig->p_bools.nprim;
+
+	return 0;
+}
+
+void cond_policydb_destroy_dup(struct policydb *p)
+{
+	hashtab_map(&p->p_bools.table, cond_bools_destroy, NULL);
+	hashtab_destroy(&p->p_bools.table);
+	cond_policydb_destroy(p);
+}
+
+int cond_policydb_dup(struct policydb *new, const struct policydb *orig)
+{
+	cond_policydb_init(new);
+
+	if (duplicate_policydb_bools(new, orig))
+		return -ENOMEM;
+
+	if (duplicate_policydb_cond_list(new, orig)) {
+		cond_policydb_destroy_dup(new);
+		return -ENOMEM;
+	}
+
+	return 0;
+}

linux-7.2.3/security/selinux/ss/conditional.h

@@ -0,0 +1,84 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Authors: Karl MacMillan <kmacmillan@tresys.com>
+ *          Frank Mayer <mayerf@tresys.com>
+ *          Copyright (C) 2003 - 2004 Tresys Technology, LLC
+ */
+
+#ifndef _CONDITIONAL_H_
+#define _CONDITIONAL_H_
+
+#include "avtab.h"
+#include "symtab.h"
+#include "policydb.h"
+#include "../include/conditional.h"
+
+#define COND_EXPR_MAXDEPTH 10
+
+/*
+ * A conditional expression is a list of operators and operands
+ * in reverse polish notation.
+ */
+struct cond_expr_node {
+#define COND_BOOL 1 /* plain bool */
+#define COND_NOT  2 /* !bool */
+#define COND_OR	  3 /* bool || bool */
+#define COND_AND  4 /* bool && bool */
+#define COND_XOR  5 /* bool ^ bool */
+#define COND_EQ	  6 /* bool == bool */
+#define COND_NEQ  7 /* bool != bool */
+#define COND_LAST COND_NEQ
+	u32 expr_type;
+	u32 boolean;
+};
+
+struct cond_expr {
+	struct cond_expr_node *nodes;
+	u32 len;
+};
+
+/*
+ * Each cond_node contains a list of rules to be enabled/disabled
+ * depending on the current value of the conditional expression. This
+ * struct is for that list.
+ */
+struct cond_av_list {
+	struct avtab_node **nodes;
+	u32 len;
+};
+
+/*
+ * A cond node represents a conditional block in a policy. It
+ * contains a conditional expression, the current state of the expression,
+ * two lists of rules to enable/disable depending on the value of the
+ * expression (the true list corresponds to if and the false list corresponds
+ * to else)..
+ */
+struct cond_node {
+	int cur_state;
+	struct cond_expr expr;
+	struct cond_av_list true_list;
+	struct cond_av_list false_list;
+};
+
+void cond_policydb_init(struct policydb *p);
+void cond_policydb_destroy(struct policydb *p);
+
+int cond_init_bool_indexes(struct policydb *p);
+int cond_destroy_bool(void *key, void *datum, void *p);
+
+int cond_index_bool(void *key, void *datum, void *datap);
+
+int cond_read_bool(struct policydb *p, struct symtab *s, struct policy_file *fp);
+int cond_read_list(struct policydb *p, struct policy_file *fp);
+int cond_write_bool(void *key, void *datum, void *ptr);
+int cond_write_list(struct policydb *p, struct policy_file *fp);
+
+void cond_compute_av(struct avtab *ctab, struct avtab_key *key,
+		     struct av_decision *avd, struct extended_perms *xperms);
+void cond_compute_xperms(struct avtab *ctab, struct avtab_key *key,
+			 struct extended_perms_decision *xpermd);
+void evaluate_cond_nodes(struct policydb *p);
+void cond_policydb_destroy_dup(struct policydb *p);
+int cond_policydb_dup(struct policydb *new, const struct policydb *orig);
+
+#endif /* _CONDITIONAL_H_ */

linux-7.2.3/security/selinux/ss/constraint.h

@@ -0,0 +1,65 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * A constraint is a condition that must be satisfied in
+ * order for one or more permissions to be granted.
+ * Constraints are used to impose additional restrictions
+ * beyond the type-based rules in `te' or the role-based
+ * transition rules in `rbac'.  Constraints are typically
+ * used to prevent a process from transitioning to a new user
+ * identity or role unless it is in a privileged type.
+ * Constraints are likewise typically used to prevent a
+ * process from labeling an object with a different user
+ * identity.
+ *
+ * Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
+ */
+
+#ifndef _SS_CONSTRAINT_H_
+#define _SS_CONSTRAINT_H_
+
+#include "ebitmap.h"
+
+#define CEXPR_MAXDEPTH 5
+
+struct constraint_expr {
+#define CEXPR_NOT   1 /* not expr */
+#define CEXPR_AND   2 /* expr and expr */
+#define CEXPR_OR    3 /* expr or expr */
+#define CEXPR_ATTR  4 /* attr op attr */
+#define CEXPR_NAMES 5 /* attr op names */
+	u32 expr_type; /* expression type */
+
+#define CEXPR_USER    1 /* user */
+#define CEXPR_ROLE    2 /* role */
+#define CEXPR_TYPE    4 /* type */
+#define CEXPR_TARGET  8 /* target if set, source otherwise */
+#define CEXPR_XTARGET 16 /* special 3rd target for validatetrans rule */
+#define CEXPR_L1L2    32 /* low level 1 vs. low level 2 */
+#define CEXPR_L1H2    64 /* low level 1 vs. high level 2 */
+#define CEXPR_H1L2    128 /* high level 1 vs. low level 2 */
+#define CEXPR_H1H2    256 /* high level 1 vs. high level 2 */
+#define CEXPR_L1H1    512 /* low level 1 vs. high level 1 */
+#define CEXPR_L2H2    1024 /* low level 2 vs. high level 2 */
+	u32 attr; /* attribute */
+
+#define CEXPR_EQ     1 /* == or eq */
+#define CEXPR_NEQ    2 /* != */
+#define CEXPR_DOM    3 /* dom */
+#define CEXPR_DOMBY  4 /* domby  */
+#define CEXPR_INCOMP 5 /* incomp */
+	u32 op; /* operator */
+
+	struct ebitmap names; /* names */
+	/* internally unused, only forwarded via policydb_write() */
+	struct type_set *type_names;
+
+	struct constraint_expr *next; /* next expression */
+};
+
+struct constraint_node {
+	u32 permissions; /* constrained permissions */
+	struct constraint_expr *expr; /* constraint on permissions */
+	struct constraint_node *next; /* next constraint */
+};
+
+#endif /* _SS_CONSTRAINT_H_ */

linux-7.2.3/security/selinux/ss/context.c

@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Implementations of the security context functions.
+ *
+ * Author: Ondrej Mosnacek <omosnacek@gmail.com>
+ * Copyright (C) 2020 Red Hat, Inc.
+ */
+
+#include <linux/jhash.h>
+
+#include "context.h"
+#include "mls.h"
+
+u32 context_compute_hash(const struct context *c)
+{
+	u32 hash = 0;
+
+	/*
+	 * If a context is invalid, it will always be represented by a
+	 * context struct with only the len & str set (and vice versa)
+	 * under a given policy. Since context structs from different
+	 * policies should never meet, it is safe to hash valid and
+	 * invalid contexts differently. The context_equal() function
+	 * already operates under the same assumption.
+	 */
+	if (c->len)
+		return full_name_hash(NULL, c->str, c->len);
+
+	hash = jhash_3words(c->user, c->role, c->type, hash);
+	hash = mls_range_hash(&c->range, hash);
+	return hash;
+}

linux-7.2.3/security/selinux/ss/context.h

@@ -0,0 +1,204 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * A security context is a set of security attributes
+ * associated with each subject and object controlled
+ * by the security policy.  Security contexts are
+  * externally represented as variable-length strings
+ * that can be interpreted by a user or application
+ * with an understanding of the security policy.
+ * Internally, the security server uses a simple
+ * structure.  This structure is private to the
+ * security server and can be changed without affecting
+ * clients of the security server.
+ *
+ * Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
+ */
+
+#ifndef _SS_CONTEXT_H_
+#define _SS_CONTEXT_H_
+
+#include "ebitmap.h"
+#include "mls_types.h"
+#include "security.h"
+
+/*
+ * A security context consists of an authenticated user
+ * identity, a role, a type and a MLS range.
+ */
+struct context {
+	u32 user;
+	u32 role;
+	u32 type;
+	u32 len; /* length of string in bytes */
+	struct mls_range range;
+	char *str; /* string representation if context cannot be mapped. */
+};
+
+static inline void mls_context_init(struct context *c)
+{
+	memset(&c->range, 0, sizeof(c->range));
+}
+
+static inline int mls_context_cpy(struct context *dst,
+				  const struct context *src)
+{
+	int rc;
+
+	dst->range.level[0].sens = src->range.level[0].sens;
+	rc = ebitmap_cpy(&dst->range.level[0].cat, &src->range.level[0].cat);
+	if (rc)
+		goto out;
+
+	dst->range.level[1].sens = src->range.level[1].sens;
+	rc = ebitmap_cpy(&dst->range.level[1].cat, &src->range.level[1].cat);
+	if (rc)
+		ebitmap_destroy(&dst->range.level[0].cat);
+out:
+	return rc;
+}
+
+/*
+ * Sets both levels in the MLS range of 'dst' to the low level of 'src'.
+ */
+static inline int mls_context_cpy_low(struct context *dst,
+				      const struct context *src)
+{
+	int rc;
+
+	dst->range.level[0].sens = src->range.level[0].sens;
+	rc = ebitmap_cpy(&dst->range.level[0].cat, &src->range.level[0].cat);
+	if (rc)
+		goto out;
+
+	dst->range.level[1].sens = src->range.level[0].sens;
+	rc = ebitmap_cpy(&dst->range.level[1].cat, &src->range.level[0].cat);
+	if (rc)
+		ebitmap_destroy(&dst->range.level[0].cat);
+out:
+	return rc;
+}
+
+/*
+ * Sets both levels in the MLS range of 'dst' to the high level of 'src'.
+ */
+static inline int mls_context_cpy_high(struct context *dst,
+				       const struct context *src)
+{
+	int rc;
+
+	dst->range.level[0].sens = src->range.level[1].sens;
+	rc = ebitmap_cpy(&dst->range.level[0].cat, &src->range.level[1].cat);
+	if (rc)
+		goto out;
+
+	dst->range.level[1].sens = src->range.level[1].sens;
+	rc = ebitmap_cpy(&dst->range.level[1].cat, &src->range.level[1].cat);
+	if (rc)
+		ebitmap_destroy(&dst->range.level[0].cat);
+out:
+	return rc;
+}
+
+static inline int mls_context_glblub(struct context *dst,
+				     const struct context *c1,
+				     const struct context *c2)
+{
+	struct mls_range *dr = &dst->range;
+	const struct mls_range *r1 = &c1->range, *r2 = &c2->range;
+	int rc = 0;
+
+	if (r1->level[1].sens < r2->level[0].sens ||
+	    r2->level[1].sens < r1->level[0].sens)
+		/* These ranges have no common sensitivities */
+		return -EINVAL;
+
+	/* Take the greatest of the low */
+	dr->level[0].sens = max(r1->level[0].sens, r2->level[0].sens);
+
+	/* Take the least of the high */
+	dr->level[1].sens = min(r1->level[1].sens, r2->level[1].sens);
+
+	rc = ebitmap_and(&dr->level[0].cat, &r1->level[0].cat,
+			 &r2->level[0].cat);
+	if (rc)
+		goto out;
+
+	rc = ebitmap_and(&dr->level[1].cat, &r1->level[1].cat,
+			 &r2->level[1].cat);
+	if (rc)
+		goto out;
+
+out:
+	return rc;
+}
+
+static inline bool mls_context_equal(const struct context *c1,
+				     const struct context *c2)
+{
+	return ((c1->range.level[0].sens == c2->range.level[0].sens) &&
+		ebitmap_equal(&c1->range.level[0].cat, &c2->range.level[0].cat) &&
+		(c1->range.level[1].sens == c2->range.level[1].sens) &&
+		ebitmap_equal(&c1->range.level[1].cat, &c2->range.level[1].cat));
+}
+
+static inline void mls_context_destroy(struct context *c)
+{
+	ebitmap_destroy(&c->range.level[0].cat);
+	ebitmap_destroy(&c->range.level[1].cat);
+	mls_context_init(c);
+}
+
+static inline void context_init(struct context *c)
+{
+	memset(c, 0, sizeof(*c));
+}
+
+static inline int context_cpy(struct context *dst, const struct context *src)
+{
+	int rc;
+
+	dst->user = src->user;
+	dst->role = src->role;
+	dst->type = src->type;
+	if (src->str) {
+		dst->str = kstrdup(src->str, GFP_ATOMIC);
+		if (!dst->str)
+			return -ENOMEM;
+		dst->len = src->len;
+	} else {
+		dst->str = NULL;
+		dst->len = 0;
+	}
+	rc = mls_context_cpy(dst, src);
+	if (rc) {
+		kfree(dst->str);
+		dst->str = NULL;
+		dst->len = 0;
+		return rc;
+	}
+	return 0;
+}
+
+static inline void context_destroy(struct context *c)
+{
+	c->user = c->role = c->type = 0;
+	kfree(c->str);
+	c->str = NULL;
+	c->len = 0;
+	mls_context_destroy(c);
+}
+
+static inline bool context_equal(const struct context *c1,
+				 const struct context *c2)
+{
+	if (c1->len && c2->len)
+		return (c1->len == c2->len && !strcmp(c1->str, c2->str));
+	if (c1->len || c2->len)
+		return 0;
+	return ((c1->user == c2->user) && (c1->role == c2->role) &&
+		(c1->type == c2->type) && mls_context_equal(c1, c2));
+}
+
+u32 context_compute_hash(const struct context *c);
+
+#endif /* _SS_CONTEXT_H_ */

linux-7.2.3/security/selinux/ss/ebitmap.c

@@ -0,0 +1,603 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Implementation of the extensible bitmap type.
+ *
+ * Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
+ */
+/*
+ * Updated: Hewlett-Packard <paul@paul-moore.com>
+ *          Added support to import/export the NetLabel category bitmap
+ *          (c) Copyright Hewlett-Packard Development Company, L.P., 2006
+ *
+ * Updated: KaiGai Kohei <kaigai@ak.jp.nec.com>
+ *          Applied standard bit operations to improve bitmap scanning.
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/jhash.h>
+#include <net/netlabel.h>
+#include "ebitmap.h"
+#include "policydb.h"
+
+#define BITS_PER_U64 ((u32)(sizeof(u64) * 8))
+
+static struct kmem_cache *ebitmap_node_cachep __ro_after_init;
+
+bool ebitmap_equal(const struct ebitmap *e1, const struct ebitmap *e2)
+{
+	const struct ebitmap_node *n1, *n2;
+
+	if (e1->highbit != e2->highbit)
+		return false;
+
+	n1 = e1->node;
+	n2 = e2->node;
+	while (n1 && n2 && (n1->startbit == n2->startbit) &&
+	       !memcmp(n1->maps, n2->maps, EBITMAP_SIZE / 8)) {
+		n1 = n1->next;
+		n2 = n2->next;
+	}
+
+	if (n1 || n2)
+		return false;
+
+	return true;
+}
+
+int ebitmap_cpy(struct ebitmap *dst, const struct ebitmap *src)
+{
+	struct ebitmap_node *new, *prev;
+	const struct ebitmap_node *n;
+
+	ebitmap_init(dst);
+	n = src->node;
+	prev = NULL;
+	while (n) {
+		new = kmem_cache_zalloc(ebitmap_node_cachep, GFP_ATOMIC);
+		if (!new) {
+			ebitmap_destroy(dst);
+			return -ENOMEM;
+		}
+		new->startbit = n->startbit;
+		memcpy(new->maps, n->maps, EBITMAP_SIZE / 8);
+		new->next = NULL;
+		if (prev)
+			prev->next = new;
+		else
+			dst->node = new;
+		prev = new;
+		n = n->next;
+	}
+
+	dst->highbit = src->highbit;
+	return 0;
+}
+
+int ebitmap_and(struct ebitmap *dst, const struct ebitmap *e1,
+		const struct ebitmap *e2)
+{
+	struct ebitmap_node *n;
+	u32 bit;
+	int rc;
+
+	ebitmap_init(dst);
+
+	ebitmap_for_each_positive_bit(e1, n, bit)
+	{
+		if (ebitmap_get_bit(e2, bit)) {
+			rc = ebitmap_set_bit(dst, bit, 1);
+			if (rc < 0)
+				return rc;
+		}
+	}
+	return 0;
+}
+
+#ifdef CONFIG_NETLABEL
+/**
+ * ebitmap_netlbl_export - Export an ebitmap into a NetLabel category bitmap
+ * @ebmap: the ebitmap to export
+ * @catmap: the NetLabel category bitmap
+ *
+ * Description:
+ * Export a SELinux extensibile bitmap into a NetLabel category bitmap.
+ * Returns zero on success, negative values on error.
+ *
+ */
+int ebitmap_netlbl_export(struct ebitmap *ebmap,
+			  struct netlbl_lsm_catmap **catmap)
+{
+	struct ebitmap_node *e_iter = ebmap->node;
+	unsigned long e_map;
+	u32 offset;
+	unsigned int iter;
+	int rc;
+
+	if (e_iter == NULL) {
+		*catmap = NULL;
+		return 0;
+	}
+
+	if (*catmap != NULL)
+		netlbl_catmap_free(*catmap);
+	*catmap = NULL;
+
+	while (e_iter) {
+		offset = e_iter->startbit;
+		for (iter = 0; iter < EBITMAP_UNIT_NUMS; iter++) {
+			e_map = e_iter->maps[iter];
+			if (e_map != 0) {
+				rc = netlbl_catmap_setlong(catmap, offset,
+							   e_map, GFP_ATOMIC);
+				if (rc != 0)
+					goto netlbl_export_failure;
+			}
+			offset += EBITMAP_UNIT_SIZE;
+		}
+		e_iter = e_iter->next;
+	}
+
+	return 0;
+
+netlbl_export_failure:
+	netlbl_catmap_free(*catmap);
+	return -ENOMEM;
+}
+
+/**
+ * ebitmap_netlbl_import - Import a NetLabel category bitmap into an ebitmap
+ * @ebmap: the ebitmap to import
+ * @catmap: the NetLabel category bitmap
+ *
+ * Description:
+ * Import a NetLabel category bitmap into a SELinux extensibile bitmap.
+ * Returns zero on success, negative values on error.
+ *
+ */
+int ebitmap_netlbl_import(struct ebitmap *ebmap,
+			  struct netlbl_lsm_catmap *catmap)
+{
+	int rc;
+	struct ebitmap_node *e_iter = NULL;
+	struct ebitmap_node *e_prev = NULL;
+	u32 offset = 0, idx;
+	unsigned long bitmap;
+
+	for (;;) {
+		rc = netlbl_catmap_getlong(catmap, &offset, &bitmap);
+		if (rc < 0)
+			goto netlbl_import_failure;
+		if (offset == (u32)-1)
+			return 0;
+
+		/* don't waste ebitmap space if the netlabel bitmap is empty */
+		if (bitmap == 0) {
+			offset += EBITMAP_UNIT_SIZE;
+			continue;
+		}
+
+		if (e_iter == NULL ||
+		    offset >= e_iter->startbit + EBITMAP_SIZE) {
+			e_prev = e_iter;
+			e_iter = kmem_cache_zalloc(ebitmap_node_cachep,
+						   GFP_ATOMIC);
+			if (e_iter == NULL)
+				goto netlbl_import_failure;
+			e_iter->startbit = offset - (offset % EBITMAP_SIZE);
+			if (e_prev == NULL)
+				ebmap->node = e_iter;
+			else
+				e_prev->next = e_iter;
+			ebmap->highbit = e_iter->startbit + EBITMAP_SIZE;
+		}
+
+		/* offset will always be aligned to an unsigned long */
+		idx = EBITMAP_NODE_INDEX(e_iter, offset);
+		e_iter->maps[idx] = bitmap;
+
+		/* next */
+		offset += EBITMAP_UNIT_SIZE;
+	}
+
+	/* NOTE: we should never reach this return */
+	return 0;
+
+netlbl_import_failure:
+	ebitmap_destroy(ebmap);
+	return -ENOMEM;
+}
+#endif /* CONFIG_NETLABEL */
+
+/*
+ * Check to see if all the bits set in e2 are also set in e1. Optionally,
+ * if last_e2bit is non-zero, the highest set bit in e2 cannot exceed
+ * last_e2bit.
+ */
+int ebitmap_contains(const struct ebitmap *e1, const struct ebitmap *e2,
+		     u32 last_e2bit)
+{
+	const struct ebitmap_node *n1, *n2;
+	int i;
+
+	if (e1->highbit < e2->highbit)
+		return 0;
+
+	n1 = e1->node;
+	n2 = e2->node;
+
+	while (n1 && n2 && (n1->startbit <= n2->startbit)) {
+		if (n1->startbit < n2->startbit) {
+			n1 = n1->next;
+			continue;
+		}
+		for (i = EBITMAP_UNIT_NUMS - 1; (i >= 0) && !n2->maps[i];)
+			i--; /* Skip trailing NULL map entries */
+		if (last_e2bit && (i >= 0)) {
+			u32 lastsetbit = n2->startbit + i * EBITMAP_UNIT_SIZE +
+					 __fls(n2->maps[i]);
+			if (lastsetbit > last_e2bit)
+				return 0;
+		}
+
+		while (i >= 0) {
+			if ((n1->maps[i] & n2->maps[i]) != n2->maps[i])
+				return 0;
+			i--;
+		}
+
+		n1 = n1->next;
+		n2 = n2->next;
+	}
+
+	if (n2)
+		return 0;
+
+	return 1;
+}
+
+u32 ebitmap_get_highest_set_bit(const struct ebitmap *e)
+{
+	const struct ebitmap_node *n;
+	unsigned long unit;
+	u32 pos = 0;
+
+	n = e->node;
+	if (!n)
+		return 0;
+
+	while (n->next)
+		n = n->next;
+
+	for (unsigned int i = EBITMAP_UNIT_NUMS; i > 0; i--) {
+		unit = n->maps[i - 1];
+		if (unit == 0)
+			continue;
+
+		pos = (i - 1) * EBITMAP_UNIT_SIZE;
+		while (unit >>= 1)
+			pos++;
+		break;
+	}
+
+	return n->startbit + pos;
+}
+
+int ebitmap_get_bit(const struct ebitmap *e, u32 bit)
+{
+	const struct ebitmap_node *n;
+
+	if (e->highbit < bit)
+		return 0;
+
+	n = e->node;
+	while (n && (n->startbit <= bit)) {
+		if ((n->startbit + EBITMAP_SIZE) > bit)
+			return ebitmap_node_get_bit(n, bit);
+		n = n->next;
+	}
+
+	return 0;
+}
+
+int ebitmap_set_bit(struct ebitmap *e, u32 bit, int value)
+{
+	struct ebitmap_node *n, *prev, *new;
+
+	prev = NULL;
+	n = e->node;
+	while (n && n->startbit <= bit) {
+		if ((n->startbit + EBITMAP_SIZE) > bit) {
+			if (value) {
+				ebitmap_node_set_bit(n, bit);
+			} else {
+				u32 s;
+
+				ebitmap_node_clr_bit(n, bit);
+
+				s = find_first_bit(n->maps, EBITMAP_SIZE);
+				if (s < EBITMAP_SIZE)
+					return 0;
+
+				/* drop this node from the bitmap */
+				if (!n->next) {
+					/*
+					 * this was the highest map
+					 * within the bitmap
+					 */
+					if (prev)
+						e->highbit = prev->startbit +
+							     EBITMAP_SIZE;
+					else
+						e->highbit = 0;
+				}
+				if (prev)
+					prev->next = n->next;
+				else
+					e->node = n->next;
+				kmem_cache_free(ebitmap_node_cachep, n);
+			}
+			return 0;
+		}
+		prev = n;
+		n = n->next;
+	}
+
+	if (!value)
+		return 0;
+
+	new = kmem_cache_zalloc(ebitmap_node_cachep, GFP_ATOMIC);
+	if (!new)
+		return -ENOMEM;
+
+	new->startbit = bit - (bit % EBITMAP_SIZE);
+	ebitmap_node_set_bit(new, bit);
+
+	if (!n)
+		/* this node will be the highest map within the bitmap */
+		e->highbit = new->startbit + EBITMAP_SIZE;
+
+	if (prev) {
+		new->next = prev->next;
+		prev->next = new;
+	} else {
+		new->next = e->node;
+		e->node = new;
+	}
+
+	return 0;
+}
+
+void ebitmap_destroy(struct ebitmap *e)
+{
+	struct ebitmap_node *n, *temp;
+
+	if (!e)
+		return;
+
+	n = e->node;
+	while (n) {
+		temp = n;
+		n = n->next;
+		kmem_cache_free(ebitmap_node_cachep, temp);
+	}
+
+	e->highbit = 0;
+	e->node = NULL;
+}
+
+int ebitmap_read(struct ebitmap *e, struct policy_file *fp)
+{
+	struct ebitmap_node *n = NULL;
+	u32 mapunit, count, startbit, index, i;
+	__le32 ebitmap_start;
+	u64 map;
+	__le64 mapbits;
+	__le32 buf[3];
+	int rc;
+
+	ebitmap_init(e);
+
+	rc = next_entry(buf, fp, sizeof buf);
+	if (rc < 0)
+		goto out;
+
+	mapunit = le32_to_cpu(buf[0]);
+	e->highbit = le32_to_cpu(buf[1]);
+	count = le32_to_cpu(buf[2]);
+
+	if (mapunit != BITS_PER_U64) {
+		pr_err("SELinux: ebitmap: map size %u does not "
+		       "match my size %u (high bit was %u)\n",
+		       mapunit, BITS_PER_U64, e->highbit);
+		goto bad;
+	}
+
+	/* round up e->highbit */
+	e->highbit += EBITMAP_SIZE - 1;
+	e->highbit -= (e->highbit % EBITMAP_SIZE);
+
+	if (!e->highbit) {
+		e->node = NULL;
+		goto ok;
+	}
+
+	if (e->highbit && !count)
+		goto bad;
+
+	for (i = 0; i < count; i++) {
+		rc = next_entry(&ebitmap_start, fp, sizeof(u32));
+		if (rc < 0) {
+			pr_err("SELinux: ebitmap: truncated map\n");
+			goto bad;
+		}
+		startbit = le32_to_cpu(ebitmap_start);
+
+		if (startbit & (mapunit - 1)) {
+			pr_err("SELinux: ebitmap start bit (%u) is "
+			       "not a multiple of the map unit size (%u)\n",
+			       startbit, mapunit);
+			goto bad;
+		}
+		if (startbit > e->highbit - mapunit) {
+			pr_err("SELinux: ebitmap start bit (%u) is "
+			       "beyond the end of the bitmap (%u)\n",
+			       startbit, (e->highbit - mapunit));
+			goto bad;
+		}
+
+		if (!n || startbit >= n->startbit + EBITMAP_SIZE) {
+			struct ebitmap_node *tmp;
+			tmp = kmem_cache_zalloc(ebitmap_node_cachep,
+						GFP_KERNEL);
+			if (!tmp) {
+				pr_err("SELinux: ebitmap: out of memory\n");
+				rc = -ENOMEM;
+				goto bad;
+			}
+			/* round down */
+			tmp->startbit = startbit - (startbit % EBITMAP_SIZE);
+			if (n)
+				n->next = tmp;
+			else
+				e->node = tmp;
+			n = tmp;
+		} else if (startbit <= n->startbit) {
+			pr_err("SELinux: ebitmap: start bit %u"
+			       " comes after start bit %u\n",
+			       startbit, n->startbit);
+			goto bad;
+		}
+
+		rc = next_entry(&mapbits, fp, sizeof(u64));
+		if (rc < 0) {
+			pr_err("SELinux: ebitmap: truncated map\n");
+			goto bad;
+		}
+		map = le64_to_cpu(mapbits);
+		if (!map) {
+			pr_err("SELinux: ebitmap: empty map\n");
+			goto bad;
+		}
+
+		index = (startbit - n->startbit) / EBITMAP_UNIT_SIZE;
+		while (map) {
+			n->maps[index++] = map & (-1UL);
+			map = EBITMAP_SHIFT_UNIT_SIZE(map);
+		}
+	}
+
+	if (n && n->startbit + EBITMAP_SIZE != e->highbit) {
+		pr_err("SELinux: ebitmap: high bit %u is not equal to the expected value %zu\n",
+		       e->highbit, n->startbit + EBITMAP_SIZE);
+		goto bad;
+	}
+
+ok:
+	rc = 0;
+out:
+	return rc;
+bad:
+	if (!rc)
+		rc = -EINVAL;
+	ebitmap_destroy(e);
+	goto out;
+}
+
+int ebitmap_write(const struct ebitmap *e, struct policy_file *fp)
+{
+	struct ebitmap_node *n;
+	u32 bit, count, last_bit, last_startbit;
+	__le32 buf[3];
+	u64 map;
+	int rc;
+
+	buf[0] = cpu_to_le32(BITS_PER_U64);
+
+	count = 0;
+	last_bit = 0;
+	last_startbit = U32_MAX;
+	ebitmap_for_each_positive_bit(e, n, bit)
+	{
+		if (last_startbit == U32_MAX ||
+		    rounddown(bit, BITS_PER_U64) > last_startbit) {
+			count++;
+			last_startbit = rounddown(bit, BITS_PER_U64);
+		}
+		last_bit = roundup(bit + 1, BITS_PER_U64);
+	}
+	buf[1] = cpu_to_le32(last_bit);
+	buf[2] = cpu_to_le32(count);
+
+	rc = put_entry(buf, sizeof(u32), 3, fp);
+	if (rc)
+		return rc;
+
+	map = 0;
+	last_startbit = U32_MAX;
+	ebitmap_for_each_positive_bit(e, n, bit)
+	{
+		if (last_startbit == U32_MAX ||
+		    rounddown(bit, BITS_PER_U64) > last_startbit) {
+			__le64 buf64[1];
+
+			/* this is the very first bit */
+			if (!map) {
+				last_startbit = rounddown(bit, BITS_PER_U64);
+				map = (u64)1 << (bit - last_startbit);
+				continue;
+			}
+
+			/* write the last node */
+			buf[0] = cpu_to_le32(last_startbit);
+			rc = put_entry(buf, sizeof(u32), 1, fp);
+			if (rc)
+				return rc;
+
+			buf64[0] = cpu_to_le64(map);
+			rc = put_entry(buf64, sizeof(u64), 1, fp);
+			if (rc)
+				return rc;
+
+			/* set up for the next node */
+			map = 0;
+			last_startbit = rounddown(bit, BITS_PER_U64);
+		}
+		map |= (u64)1 << (bit - last_startbit);
+	}
+	/* write the last node */
+	if (map) {
+		__le64 buf64[1];
+
+		/* write the last node */
+		buf[0] = cpu_to_le32(last_startbit);
+		rc = put_entry(buf, sizeof(u32), 1, fp);
+		if (rc)
+			return rc;
+
+		buf64[0] = cpu_to_le64(map);
+		rc = put_entry(buf64, sizeof(u64), 1, fp);
+		if (rc)
+			return rc;
+	}
+	return 0;
+}
+
+u32 ebitmap_hash(const struct ebitmap *e, u32 hash)
+{
+	struct ebitmap_node *node;
+
+	/* need to change hash even if ebitmap is empty */
+	hash = jhash_1word(e->highbit, hash);
+	for (node = e->node; node; node = node->next) {
+		hash = jhash_1word(node->startbit, hash);
+		hash = jhash(node->maps, sizeof(node->maps), hash);
+	}
+	return hash;
+}
+
+void __init ebitmap_cache_init(void)
+{
+	ebitmap_node_cachep = KMEM_CACHE(ebitmap_node, SLAB_PANIC);
+}

linux-7.2.3/security/selinux/ss/ebitmap.h

@@ -0,0 +1,156 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * An extensible bitmap is a bitmap that supports an
+ * arbitrary number of bits.  Extensible bitmaps are
+ * used to represent sets of values, such as types,
+ * roles, categories, and classes.
+ *
+ * Each extensible bitmap is implemented as a linked
+ * list of bitmap nodes, where each bitmap node has
+ * an explicitly specified starting bit position within
+ * the total bitmap.
+ *
+ * Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
+ */
+
+#ifndef _SS_EBITMAP_H_
+#define _SS_EBITMAP_H_
+
+#include <net/netlabel.h>
+
+#ifdef CONFIG_64BIT
+#define EBITMAP_NODE_SIZE 64
+#else
+#define EBITMAP_NODE_SIZE 32
+#endif
+
+#define EBITMAP_UNIT_NUMS                                     \
+	((EBITMAP_NODE_SIZE - sizeof(void *) - sizeof(u32)) / \
+	 sizeof(unsigned long))
+#define EBITMAP_UNIT_SIZE BITS_PER_LONG
+#define EBITMAP_SIZE	  (EBITMAP_UNIT_NUMS * EBITMAP_UNIT_SIZE)
+#define EBITMAP_BIT	  1UL
+#define EBITMAP_SHIFT_UNIT_SIZE(x) \
+	(((x) >> EBITMAP_UNIT_SIZE / 2) >> EBITMAP_UNIT_SIZE / 2)
+
+struct ebitmap_node {
+	struct ebitmap_node *next;
+	unsigned long maps[EBITMAP_UNIT_NUMS];
+	u32 startbit;
+};
+
+struct ebitmap {
+	struct ebitmap_node *node; /* first node in the bitmap */
+	u32 highbit; /* highest position in the total bitmap */
+};
+
+#define ebitmap_length(e) ((e)->highbit)
+
+static inline u32 ebitmap_start_positive(const struct ebitmap *e,
+					 struct ebitmap_node **n)
+{
+	u32 ofs;
+
+	for (*n = e->node; *n; *n = (*n)->next) {
+		ofs = find_first_bit((*n)->maps, EBITMAP_SIZE);
+		if (ofs < EBITMAP_SIZE)
+			return (*n)->startbit + ofs;
+	}
+	return ebitmap_length(e);
+}
+
+static inline void ebitmap_init(struct ebitmap *e)
+{
+	memset(e, 0, sizeof(*e));
+}
+
+static inline u32 ebitmap_next_positive(const struct ebitmap *e,
+					struct ebitmap_node **n, u32 bit)
+{
+	u32 ofs;
+
+	ofs = find_next_bit((*n)->maps, EBITMAP_SIZE, bit - (*n)->startbit + 1);
+	if (ofs < EBITMAP_SIZE)
+		return ofs + (*n)->startbit;
+
+	for (*n = (*n)->next; *n; *n = (*n)->next) {
+		ofs = find_first_bit((*n)->maps, EBITMAP_SIZE);
+		if (ofs < EBITMAP_SIZE)
+			return ofs + (*n)->startbit;
+	}
+	return ebitmap_length(e);
+}
+
+#define EBITMAP_NODE_INDEX(node, bit) \
+	(((bit) - (node)->startbit) / EBITMAP_UNIT_SIZE)
+#define EBITMAP_NODE_OFFSET(node, bit) \
+	(((bit) - (node)->startbit) % EBITMAP_UNIT_SIZE)
+
+static inline int ebitmap_node_get_bit(const struct ebitmap_node *n, u32 bit)
+{
+	u32 index = EBITMAP_NODE_INDEX(n, bit);
+	u32 ofs = EBITMAP_NODE_OFFSET(n, bit);
+
+	BUG_ON(index >= EBITMAP_UNIT_NUMS);
+	if ((n->maps[index] & (EBITMAP_BIT << ofs)))
+		return 1;
+	return 0;
+}
+
+static inline void ebitmap_node_set_bit(struct ebitmap_node *n, u32 bit)
+{
+	u32 index = EBITMAP_NODE_INDEX(n, bit);
+	u32 ofs = EBITMAP_NODE_OFFSET(n, bit);
+
+	BUG_ON(index >= EBITMAP_UNIT_NUMS);
+	n->maps[index] |= (EBITMAP_BIT << ofs);
+}
+
+static inline void ebitmap_node_clr_bit(struct ebitmap_node *n, u32 bit)
+{
+	u32 index = EBITMAP_NODE_INDEX(n, bit);
+	u32 ofs = EBITMAP_NODE_OFFSET(n, bit);
+
+	BUG_ON(index >= EBITMAP_UNIT_NUMS);
+	n->maps[index] &= ~(EBITMAP_BIT << ofs);
+}
+
+#define ebitmap_for_each_positive_bit(e, n, bit)      \
+	for ((bit) = ebitmap_start_positive(e, &(n)); \
+	     (bit) < ebitmap_length(e);               \
+	     (bit) = ebitmap_next_positive(e, &(n), bit))
+
+bool ebitmap_equal(const struct ebitmap *e1, const struct ebitmap *e2);
+int ebitmap_cpy(struct ebitmap *dst, const struct ebitmap *src);
+int ebitmap_and(struct ebitmap *dst, const struct ebitmap *e1,
+		const struct ebitmap *e2);
+int ebitmap_contains(const struct ebitmap *e1, const struct ebitmap *e2,
+		     u32 last_e2bit);
+u32 ebitmap_get_highest_set_bit(const struct ebitmap *e);
+int ebitmap_get_bit(const struct ebitmap *e, u32 bit);
+int ebitmap_set_bit(struct ebitmap *e, u32 bit, int value);
+void ebitmap_destroy(struct ebitmap *e);
+struct policy_file;
+int ebitmap_read(struct ebitmap *e, struct policy_file *fp);
+int ebitmap_write(const struct ebitmap *e, struct policy_file *fp);
+u32 ebitmap_hash(const struct ebitmap *e, u32 hash);
+
+#ifdef CONFIG_NETLABEL
+int ebitmap_netlbl_export(struct ebitmap *ebmap,
+			  struct netlbl_lsm_catmap **catmap);
+int ebitmap_netlbl_import(struct ebitmap *ebmap,
+			  struct netlbl_lsm_catmap *catmap);
+#else
+static inline int ebitmap_netlbl_export(struct ebitmap *ebmap,
+					struct netlbl_lsm_catmap **catmap)
+{
+	return -ENOMEM;
+}
+static inline int ebitmap_netlbl_import(struct ebitmap *ebmap,
+					struct netlbl_lsm_catmap *catmap)
+{
+	return -ENOMEM;
+}
+#endif
+
+#endif /* _SS_EBITMAP_H_ */

linux-7.2.3/security/selinux/ss/hashtab.c

@@ -0,0 +1,199 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Implementation of the hash table type.
+ *
+ * Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include "hashtab.h"
+#include "security.h"
+
+static struct kmem_cache *hashtab_node_cachep __ro_after_init;
+
+/*
+ * Here we simply round the number of elements up to the nearest power of two.
+ * I tried also other options like rounding down or rounding to the closest
+ * power of two (up or down based on which is closer), but I was unable to
+ * find any significant difference in lookup/insert performance that would
+ * justify switching to a different (less intuitive) formula. It could be that
+ * a different formula is actually more optimal, but any future changes here
+ * should be supported with performance/memory usage data.
+ *
+ * The total memory used by the htable arrays (only) with Fedora policy loaded
+ * is approximately 163 KB at the time of writing.
+ */
+static u32 hashtab_compute_size(u32 nel)
+{
+	return nel == 0 ? 0 : roundup_pow_of_two(nel);
+}
+
+int hashtab_init(struct hashtab *h, u32 nel_hint)
+{
+	u32 size = hashtab_compute_size(nel_hint);
+
+	/* should already be zeroed, but better be safe */
+	h->nel = 0;
+	h->size = 0;
+	h->htable = NULL;
+
+	if (size) {
+		h->htable = kzalloc_objs(*h->htable, size,
+					 GFP_KERNEL | __GFP_NOWARN);
+		if (!h->htable)
+			return -ENOMEM;
+		h->size = size;
+	}
+	return 0;
+}
+
+int __hashtab_insert(struct hashtab *h, struct hashtab_node **dst, void *key,
+		     void *datum)
+{
+	struct hashtab_node *newnode;
+
+	newnode = kmem_cache_zalloc(hashtab_node_cachep, GFP_KERNEL);
+	if (!newnode)
+		return -ENOMEM;
+	newnode->key = key;
+	newnode->datum = datum;
+	newnode->next = *dst;
+	*dst = newnode;
+
+	h->nel++;
+	return 0;
+}
+
+void hashtab_destroy(struct hashtab *h)
+{
+	u32 i;
+	struct hashtab_node *cur, *temp;
+
+	for (i = 0; i < h->size; i++) {
+		cur = h->htable[i];
+		while (cur) {
+			temp = cur;
+			cur = cur->next;
+			kmem_cache_free(hashtab_node_cachep, temp);
+		}
+		h->htable[i] = NULL;
+	}
+
+	kfree(h->htable);
+	h->htable = NULL;
+}
+
+int hashtab_map(struct hashtab *h, int (*apply)(void *k, void *d, void *args),
+		void *args)
+{
+	u32 i;
+	int ret;
+	struct hashtab_node *cur;
+
+	for (i = 0; i < h->size; i++) {
+		cur = h->htable[i];
+		while (cur) {
+			ret = apply(cur->key, cur->datum, args);
+			if (ret)
+				return ret;
+			cur = cur->next;
+		}
+	}
+	return 0;
+}
+
+#ifdef CONFIG_SECURITY_SELINUX_DEBUG
+void hashtab_stat(struct hashtab *h, struct hashtab_info *info)
+{
+	u32 i, chain_len, slots_used, max_chain_len;
+	u64 chain2_len_sum;
+	struct hashtab_node *cur;
+
+	slots_used = 0;
+	max_chain_len = 0;
+	chain2_len_sum = 0;
+	for (i = 0; i < h->size; i++) {
+		cur = h->htable[i];
+		if (cur) {
+			slots_used++;
+			chain_len = 0;
+			while (cur) {
+				chain_len++;
+				cur = cur->next;
+			}
+
+			if (chain_len > max_chain_len)
+				max_chain_len = chain_len;
+
+			chain2_len_sum += (u64)chain_len * chain_len;
+		}
+	}
+
+	info->slots_used = slots_used;
+	info->max_chain_len = max_chain_len;
+	info->chain2_len_sum = chain2_len_sum;
+}
+#endif /* CONFIG_SECURITY_SELINUX_DEBUG */
+
+int hashtab_duplicate(struct hashtab *new, const struct hashtab *orig,
+		      int (*copy)(struct hashtab_node *new,
+				  const struct hashtab_node *orig, void *args),
+		      int (*destroy)(void *k, void *d, void *args), void *args)
+{
+	const struct hashtab_node *orig_cur;
+	struct hashtab_node *cur, *tmp, *tail;
+	u32 i;
+	int rc;
+
+	memset(new, 0, sizeof(*new));
+
+	new->htable = kzalloc_objs(*new->htable, orig->size);
+	if (!new->htable)
+		return -ENOMEM;
+
+	new->size = orig->size;
+
+	for (i = 0; i < orig->size; i++) {
+		tail = NULL;
+		for (orig_cur = orig->htable[i]; orig_cur;
+		     orig_cur = orig_cur->next) {
+			tmp = kmem_cache_zalloc(hashtab_node_cachep,
+						GFP_KERNEL);
+			if (!tmp)
+				goto error;
+			rc = copy(tmp, orig_cur, args);
+			if (rc) {
+				kmem_cache_free(hashtab_node_cachep, tmp);
+				goto error;
+			}
+			tmp->next = NULL;
+			if (!tail)
+				new->htable[i] = tmp;
+			else
+				tail->next = tmp;
+			tail = tmp;
+			new->nel++;
+		}
+	}
+
+	return 0;
+
+error:
+	for (i = 0; i < new->size; i++) {
+		for (cur = new->htable[i]; cur; cur = tmp) {
+			tmp = cur->next;
+			destroy(cur->key, cur->datum, args);
+			kmem_cache_free(hashtab_node_cachep, cur);
+		}
+	}
+	kfree(new->htable);
+	memset(new, 0, sizeof(*new));
+	return -ENOMEM;
+}
+
+void __init hashtab_cache_init(void)
+{
+	hashtab_node_cachep = KMEM_CACHE(hashtab_node, SLAB_PANIC);
+}

linux-7.2.3/security/selinux/ss/hashtab.h

@@ -0,0 +1,154 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * A hash table (hashtab) maintains associations between
+ * key values and datum values.  The type of the key values
+ * and the type of the datum values is arbitrary.  The
+ * functions for hash computation and key comparison are
+ * provided by the creator of the table.
+ *
+ * Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
+ */
+
+#ifndef _SS_HASHTAB_H_
+#define _SS_HASHTAB_H_
+
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+
+#define HASHTAB_MAX_NODES U32_MAX
+
+struct hashtab_key_params {
+	u32 (*hash)(const void *key); /* hash func */
+	int (*cmp)(const void *key1, const void *key2); /* comparison func */
+};
+
+struct hashtab_node {
+	void *key;
+	void *datum;
+	struct hashtab_node *next;
+};
+
+struct hashtab {
+	struct hashtab_node **htable; /* hash table */
+	u32 size; /* number of slots in hash table */
+	u32 nel; /* number of elements in hash table */
+};
+
+struct hashtab_info {
+	u32 slots_used;
+	u32 max_chain_len;
+	u64 chain2_len_sum;
+};
+
+/*
+ * Initializes a new hash table with the specified characteristics.
+ *
+ * Returns -ENOMEM if insufficient space is available or 0 otherwise.
+ */
+int hashtab_init(struct hashtab *h, u32 nel_hint);
+
+int __hashtab_insert(struct hashtab *h, struct hashtab_node **dst, void *key,
+		     void *datum);
+
+/*
+ * Inserts the specified (key, datum) pair into the specified hash table.
+ *
+ * Returns -ENOMEM on memory allocation error,
+ * -EEXIST if there is already an entry with the same key,
+ * -EINVAL for general errors or
+  0 otherwise.
+ */
+static inline int hashtab_insert(struct hashtab *h, void *key, void *datum,
+				 struct hashtab_key_params key_params)
+{
+	u32 hvalue;
+	struct hashtab_node *prev, *cur;
+
+	cond_resched();
+
+	if (!h->size || h->nel == HASHTAB_MAX_NODES)
+		return -EINVAL;
+
+	hvalue = key_params.hash(key) & (h->size - 1);
+	prev = NULL;
+	cur = h->htable[hvalue];
+	while (cur) {
+		int cmp = key_params.cmp(key, cur->key);
+
+		if (cmp == 0)
+			return -EEXIST;
+		if (cmp < 0)
+			break;
+		prev = cur;
+		cur = cur->next;
+	}
+
+	return __hashtab_insert(h, prev ? &prev->next : &h->htable[hvalue], key,
+				datum);
+}
+
+/*
+ * Searches for the entry with the specified key in the hash table.
+ *
+ * Returns NULL if no entry has the specified key or
+ * the datum of the entry otherwise.
+ */
+static inline void *hashtab_search(const struct hashtab *h, const void *key,
+				   struct hashtab_key_params key_params)
+{
+	u32 hvalue;
+	const struct hashtab_node *cur;
+
+	if (!h->size)
+		return NULL;
+
+	hvalue = key_params.hash(key) & (h->size - 1);
+	cur = h->htable[hvalue];
+	while (cur) {
+		int cmp = key_params.cmp(key, cur->key);
+
+		if (cmp == 0)
+			return cur->datum;
+		if (cmp < 0)
+			break;
+		cur = cur->next;
+	}
+	return NULL;
+}
+
+/*
+ * Destroys the specified hash table.
+ */
+void hashtab_destroy(struct hashtab *h);
+
+/*
+ * Applies the specified apply function to (key,datum,args)
+ * for each entry in the specified hash table.
+ *
+ * The order in which the function is applied to the entries
+ * is dependent upon the internal structure of the hash table.
+ *
+ * If apply returns a non-zero status, then hashtab_map will cease
+ * iterating through the hash table and will propagate the error
+ * return to its caller.
+ */
+int hashtab_map(struct hashtab *h, int (*apply)(void *k, void *d, void *args),
+		void *args);
+
+int hashtab_duplicate(struct hashtab *new, const struct hashtab *orig,
+		      int (*copy)(struct hashtab_node *new,
+				  const struct hashtab_node *orig, void *args),
+		      int (*destroy)(void *k, void *d, void *args), void *args);
+
+#ifdef CONFIG_SECURITY_SELINUX_DEBUG
+/* Fill info with some hash table statistics */
+void hashtab_stat(struct hashtab *h, struct hashtab_info *info);
+#else
+static inline void hashtab_stat(struct hashtab *h, struct hashtab_info *info)
+{
+	return;
+}
+#endif
+
+#endif /* _SS_HASHTAB_H */

linux-7.2.3/security/selinux/ss/mls.c

@@ -0,0 +1,653 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Implementation of the multi-level security (MLS) policy.
+ *
+ * Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
+ */
+
+/*
+ * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
+ *          Support for enhanced MLS infrastructure.
+ *          Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
+ *
+ * Updated: Hewlett-Packard <paul@paul-moore.com>
+ *          Added support to import/export the MLS label from NetLabel
+ *          Copyright (C) Hewlett-Packard Development Company, L.P., 2006
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <net/netlabel.h>
+#include "sidtab.h"
+#include "mls.h"
+#include "policydb.h"
+#include "services.h"
+
+/*
+ * Return the length in bytes for the MLS fields of the
+ * security context string representation of `context'.
+ */
+int mls_compute_context_len(struct policydb *p, struct context *context)
+{
+	int i, l, len, head, prev;
+	const char *nm;
+	struct ebitmap *e;
+	struct ebitmap_node *node;
+
+	if (!p->mls_enabled)
+		return 0;
+
+	len = 1; /* for the beginning ":" */
+	for (l = 0; l < 2; l++) {
+		u32 index_sens = context->range.level[l].sens;
+		len += strlen(sym_name(p, SYM_LEVELS, index_sens - 1));
+
+		/* categories */
+		head = -2;
+		prev = -2;
+		e = &context->range.level[l].cat;
+		ebitmap_for_each_positive_bit(e, node, i)
+		{
+			if (i - prev > 1) {
+				/* one or more negative bits are skipped */
+				if (head != prev) {
+					nm = sym_name(p, SYM_CATS, prev);
+					len += strlen(nm) + 1;
+				}
+				nm = sym_name(p, SYM_CATS, i);
+				len += strlen(nm) + 1;
+				head = i;
+			}
+			prev = i;
+		}
+		if (prev != head) {
+			nm = sym_name(p, SYM_CATS, prev);
+			len += strlen(nm) + 1;
+		}
+		if (l == 0) {
+			if (mls_level_eq(&context->range.level[0],
+					 &context->range.level[1]))
+				break;
+			else
+				len++;
+		}
+	}
+
+	return len;
+}
+
+/*
+ * Write the security context string representation of
+ * the MLS fields of `context' into the string `*scontext'.
+ * Update `*scontext' to point to the end of the MLS fields.
+ */
+void mls_sid_to_context(struct policydb *p, struct context *context,
+			char **scontext)
+{
+	const char *nm;
+	char *scontextp;
+	int i, l, head, prev;
+	struct ebitmap *e;
+	struct ebitmap_node *node;
+
+	if (!p->mls_enabled)
+		return;
+
+	scontextp = *scontext;
+
+	*scontextp = ':';
+	scontextp++;
+
+	for (l = 0; l < 2; l++) {
+		strcpy(scontextp, sym_name(p, SYM_LEVELS,
+					   context->range.level[l].sens - 1));
+		scontextp += strlen(scontextp);
+
+		/* categories */
+		head = -2;
+		prev = -2;
+		e = &context->range.level[l].cat;
+		ebitmap_for_each_positive_bit(e, node, i)
+		{
+			if (i - prev > 1) {
+				/* one or more negative bits are skipped */
+				if (prev != head) {
+					if (prev - head > 1)
+						*scontextp++ = '.';
+					else
+						*scontextp++ = ',';
+					nm = sym_name(p, SYM_CATS, prev);
+					strcpy(scontextp, nm);
+					scontextp += strlen(nm);
+				}
+				if (prev < 0)
+					*scontextp++ = ':';
+				else
+					*scontextp++ = ',';
+				nm = sym_name(p, SYM_CATS, i);
+				strcpy(scontextp, nm);
+				scontextp += strlen(nm);
+				head = i;
+			}
+			prev = i;
+		}
+
+		if (prev != head) {
+			if (prev - head > 1)
+				*scontextp++ = '.';
+			else
+				*scontextp++ = ',';
+			nm = sym_name(p, SYM_CATS, prev);
+			strcpy(scontextp, nm);
+			scontextp += strlen(nm);
+		}
+
+		if (l == 0) {
+			if (mls_level_eq(&context->range.level[0],
+					 &context->range.level[1]))
+				break;
+			else
+				*scontextp++ = '-';
+		}
+	}
+
+	*scontext = scontextp;
+}
+
+bool mls_level_isvalid(const struct policydb *p, const struct mls_level *l)
+{
+	const char *name;
+	const struct level_datum *levdatum;
+
+	if (!l->sens || l->sens > p->p_levels.nprim)
+		return false;
+
+	name = sym_name(p, SYM_LEVELS, l->sens - 1);
+	if (!name)
+		return false;
+
+	levdatum = symtab_search(&p->p_levels, name);
+	if (!levdatum)
+		return false;
+
+	/*
+	 * l is valid iff every bit in l->cat is set in levdatum->level.cat
+	 * and no bit in l->cat is larger than p->p_cats.nprim.
+	 * policydb_index() has already verified that every bit set in
+	 * levdatum->level.cat names a defined category, so containment is
+	 * sufficient here.
+	 */
+	return ebitmap_contains(&levdatum->level.cat, &l->cat,
+				p->p_cats.nprim);
+}
+
+bool mls_range_isvalid(const struct policydb *p, const struct mls_range *r)
+{
+	return (mls_level_isvalid(p, &r->level[0]) &&
+		mls_level_isvalid(p, &r->level[1]) &&
+		mls_level_dom(&r->level[1], &r->level[0]));
+}
+
+/*
+ * Return true if the MLS fields in the security context
+ * structure `c' are valid.  Return 0 otherwise.
+ */
+bool mls_context_isvalid(const struct policydb *p, const struct context *c)
+{
+	const struct user_datum *usrdatum;
+
+	if (!p->mls_enabled)
+		return true;
+
+	if (!mls_range_isvalid(p, &c->range))
+		return false;
+
+	if (c->role == OBJECT_R_VAL)
+		return true;
+
+	/*
+	 * User must be authorized for the MLS range.
+	 */
+	if (!c->user || c->user > p->p_users.nprim)
+		return false;
+	usrdatum = p->user_val_to_struct[c->user - 1];
+	if (!usrdatum || !mls_range_contains(usrdatum->range, c->range))
+		return false; /* user may not be associated with range */
+
+	return true;
+}
+
+/*
+ * Set the MLS fields in the security context structure
+ * `context' based on the string representation in
+ * the string `scontext'.
+ *
+ * This function modifies the string in place, inserting
+ * NULL characters to terminate the MLS fields.
+ *
+ * If a def_sid is provided and no MLS field is present,
+ * copy the MLS field of the associated default context.
+ * Used for upgraded to MLS systems where objects may lack
+ * MLS fields.
+ *
+ * Policy read-lock must be held for sidtab lookup.
+ *
+ */
+int mls_context_to_sid(struct policydb *pol, char oldc, char *scontext,
+		       struct context *context, struct sidtab *s, u32 def_sid)
+{
+	char *sensitivity, *cur_cat, *next_cat, *rngptr;
+	struct level_datum *levdatum;
+	struct cat_datum *catdatum, *rngdatum;
+	u32 i;
+	int l, rc;
+	char *rangep[2];
+
+	if (!pol->mls_enabled) {
+		/*
+		 * With no MLS, only return -EINVAL if there is a MLS field
+		 * and it did not come from an xattr.
+		 */
+		if (oldc && def_sid == SECSID_NULL)
+			return -EINVAL;
+		return 0;
+	}
+
+	/*
+	 * No MLS component to the security context, try and map to
+	 * default if provided.
+	 */
+	if (!oldc) {
+		struct context *defcon;
+
+		if (def_sid == SECSID_NULL)
+			return -EINVAL;
+
+		defcon = sidtab_search(s, def_sid);
+		if (!defcon)
+			return -EINVAL;
+
+		return mls_context_cpy(context, defcon);
+	}
+
+	/*
+	 * If we're dealing with a range, figure out where the two parts
+	 * of the range begin.
+	 */
+	rangep[0] = scontext;
+	rangep[1] = strchr(scontext, '-');
+	if (rangep[1]) {
+		rangep[1][0] = '\0';
+		rangep[1]++;
+	}
+
+	/* For each part of the range: */
+	for (l = 0; l < 2; l++) {
+		/* Split sensitivity and category set. */
+		sensitivity = rangep[l];
+		if (sensitivity == NULL)
+			break;
+		next_cat = strchr(sensitivity, ':');
+		if (next_cat)
+			*(next_cat++) = '\0';
+
+		/* Parse sensitivity. */
+		levdatum = symtab_search(&pol->p_levels, sensitivity);
+		if (!levdatum)
+			return -EINVAL;
+		context->range.level[l].sens = levdatum->level.sens;
+
+		/* Extract category set. */
+		while (next_cat != NULL) {
+			cur_cat = next_cat;
+			next_cat = strchr(next_cat, ',');
+			if (next_cat != NULL)
+				*(next_cat++) = '\0';
+
+			/* Separate into range if exists */
+			rngptr = strchr(cur_cat, '.');
+			if (rngptr != NULL) {
+				/* Remove '.' */
+				*rngptr++ = '\0';
+			}
+
+			catdatum = symtab_search(&pol->p_cats, cur_cat);
+			if (!catdatum)
+				return -EINVAL;
+
+			rc = ebitmap_set_bit(&context->range.level[l].cat,
+					     catdatum->value - 1, 1);
+			if (rc)
+				return rc;
+
+			/* If range, set all categories in range */
+			if (rngptr == NULL)
+				continue;
+
+			rngdatum = symtab_search(&pol->p_cats, rngptr);
+			if (!rngdatum)
+				return -EINVAL;
+
+			if (catdatum->value >= rngdatum->value)
+				return -EINVAL;
+
+			for (i = catdatum->value; i < rngdatum->value; i++) {
+				rc = ebitmap_set_bit(
+					&context->range.level[l].cat, i, 1);
+				if (rc)
+					return rc;
+			}
+		}
+	}
+
+	/* If we didn't see a '-', the range start is also the range end. */
+	if (rangep[1] == NULL) {
+		context->range.level[1].sens = context->range.level[0].sens;
+		rc = ebitmap_cpy(&context->range.level[1].cat,
+				 &context->range.level[0].cat);
+		if (rc)
+			return rc;
+	}
+
+	return 0;
+}
+
+/*
+ * Set the MLS fields in the security context structure
+ * `context' based on the string representation in
+ * the string `str'.  This function will allocate temporary memory with the
+ * given constraints of gfp_mask.
+ */
+int mls_from_string(struct policydb *p, char *str, struct context *context,
+		    gfp_t gfp_mask)
+{
+	char *tmpstr;
+	int rc;
+
+	if (!p->mls_enabled)
+		return -EINVAL;
+
+	tmpstr = kstrdup(str, gfp_mask);
+	if (!tmpstr) {
+		rc = -ENOMEM;
+	} else {
+		rc = mls_context_to_sid(p, ':', tmpstr, context, NULL,
+					SECSID_NULL);
+		kfree(tmpstr);
+	}
+
+	return rc;
+}
+
+/*
+ * Copies the MLS range `range' into `context'.
+ */
+int mls_range_set(struct context *context, struct mls_range *range)
+{
+	int l, rc = 0;
+
+	/* Copy the MLS range into the  context */
+	for (l = 0; l < 2; l++) {
+		context->range.level[l].sens = range->level[l].sens;
+		rc = ebitmap_cpy(&context->range.level[l].cat,
+				 &range->level[l].cat);
+		if (rc)
+			break;
+	}
+
+	return rc;
+}
+
+int mls_setup_user_range(struct policydb *p, struct context *fromcon,
+			 struct user_datum *user, struct context *usercon)
+{
+	if (p->mls_enabled) {
+		struct mls_level *fromcon_sen = &(fromcon->range.level[0]);
+		struct mls_level *fromcon_clr = &(fromcon->range.level[1]);
+		struct mls_level *user_low = &(user->range.level[0]);
+		struct mls_level *user_clr = &(user->range.level[1]);
+		struct mls_level *user_def = &(user->dfltlevel);
+		struct mls_level *usercon_sen = &(usercon->range.level[0]);
+		struct mls_level *usercon_clr = &(usercon->range.level[1]);
+
+		/* Honor the user's default level if we can */
+		if (mls_level_between(user_def, fromcon_sen, fromcon_clr))
+			*usercon_sen = *user_def;
+		else if (mls_level_between(fromcon_sen, user_def, user_clr))
+			*usercon_sen = *fromcon_sen;
+		else if (mls_level_between(fromcon_clr, user_low, user_def))
+			*usercon_sen = *user_low;
+		else
+			return -EINVAL;
+
+		/* Lower the clearance of available contexts
+		   if the clearance of "fromcon" is lower than
+		   that of the user's default clearance (but
+		   only if the "fromcon" clearance dominates
+		   the user's computed sensitivity level) */
+		if (mls_level_dom(user_clr, fromcon_clr))
+			*usercon_clr = *fromcon_clr;
+		else if (mls_level_dom(fromcon_clr, user_clr))
+			*usercon_clr = *user_clr;
+		else
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
+/*
+ * Convert the MLS fields in the security context
+ * structure `oldc' from the values specified in the
+ * policy `oldp' to the values specified in the policy `newp',
+ * storing the resulting context in `newc'.
+ */
+int mls_convert_context(struct policydb *oldp, struct policydb *newp,
+			struct context *oldc, struct context *newc)
+{
+	struct level_datum *levdatum;
+	struct cat_datum *catdatum;
+	struct ebitmap_node *node;
+	u32 i;
+	int l;
+
+	if (!oldp->mls_enabled || !newp->mls_enabled)
+		return 0;
+
+	for (l = 0; l < 2; l++) {
+		const char *name = sym_name(oldp, SYM_LEVELS,
+					    oldc->range.level[l].sens - 1);
+
+		levdatum = symtab_search(&newp->p_levels, name);
+
+		if (!levdatum)
+			return -EINVAL;
+		newc->range.level[l].sens = levdatum->level.sens;
+
+		ebitmap_for_each_positive_bit(&oldc->range.level[l].cat, node,
+					      i)
+		{
+			int rc;
+
+			catdatum = symtab_search(&newp->p_cats,
+						 sym_name(oldp, SYM_CATS, i));
+			if (!catdatum)
+				return -EINVAL;
+			rc = ebitmap_set_bit(&newc->range.level[l].cat,
+					     catdatum->value - 1, 1);
+			if (rc)
+				return rc;
+		}
+	}
+
+	return 0;
+}
+
+int mls_compute_sid(struct policydb *p, struct context *scontext,
+		    struct context *tcontext, u16 tclass, u32 specified,
+		    struct context *newcontext, bool sock)
+{
+	struct range_trans rtr;
+	struct mls_range *r;
+	struct class_datum *cladatum;
+	char default_range = 0;
+
+	if (!p->mls_enabled)
+		return 0;
+
+	switch (specified) {
+	case AVTAB_TRANSITION:
+		/* Look for a range transition rule. */
+		rtr.source_type = scontext->type;
+		rtr.target_type = tcontext->type;
+		rtr.target_class = tclass;
+		r = policydb_rangetr_search(p, &rtr);
+		if (r)
+			return mls_range_set(newcontext, r);
+
+		if (tclass && tclass <= p->p_classes.nprim) {
+			cladatum = p->class_val_to_struct[tclass - 1];
+			if (cladatum)
+				default_range = cladatum->default_range;
+		}
+
+		switch (default_range) {
+		case DEFAULT_SOURCE_LOW:
+			return mls_context_cpy_low(newcontext, scontext);
+		case DEFAULT_SOURCE_HIGH:
+			return mls_context_cpy_high(newcontext, scontext);
+		case DEFAULT_SOURCE_LOW_HIGH:
+			return mls_context_cpy(newcontext, scontext);
+		case DEFAULT_TARGET_LOW:
+			return mls_context_cpy_low(newcontext, tcontext);
+		case DEFAULT_TARGET_HIGH:
+			return mls_context_cpy_high(newcontext, tcontext);
+		case DEFAULT_TARGET_LOW_HIGH:
+			return mls_context_cpy(newcontext, tcontext);
+		case DEFAULT_GLBLUB:
+			return mls_context_glblub(newcontext, scontext,
+						  tcontext);
+		}
+
+		fallthrough;
+	case AVTAB_CHANGE:
+		if ((tclass == p->process_class) || sock)
+			/* Use the process MLS attributes. */
+			return mls_context_cpy(newcontext, scontext);
+		else
+			/* Use the process effective MLS attributes. */
+			return mls_context_cpy_low(newcontext, scontext);
+	case AVTAB_MEMBER:
+		/* Use the process effective MLS attributes. */
+		return mls_context_cpy_low(newcontext, scontext);
+	}
+	return -EINVAL;
+}
+
+#ifdef CONFIG_NETLABEL
+/**
+ * mls_export_netlbl_lvl - Export the MLS sensitivity levels to NetLabel
+ * @p: the policy
+ * @context: the security context
+ * @secattr: the NetLabel security attributes
+ *
+ * Description:
+ * Given the security context copy the low MLS sensitivity level into the
+ * NetLabel MLS sensitivity level field.
+ *
+ */
+void mls_export_netlbl_lvl(struct policydb *p, struct context *context,
+			   struct netlbl_lsm_secattr *secattr)
+{
+	if (!p->mls_enabled)
+		return;
+
+	secattr->attr.mls.lvl = context->range.level[0].sens - 1;
+	secattr->flags |= NETLBL_SECATTR_MLS_LVL;
+}
+
+/**
+ * mls_import_netlbl_lvl - Import the NetLabel MLS sensitivity levels
+ * @p: the policy
+ * @context: the security context
+ * @secattr: the NetLabel security attributes
+ *
+ * Description:
+ * Given the security context and the NetLabel security attributes, copy the
+ * NetLabel MLS sensitivity level into the context.
+ *
+ */
+void mls_import_netlbl_lvl(struct policydb *p, struct context *context,
+			   struct netlbl_lsm_secattr *secattr)
+{
+	if (!p->mls_enabled)
+		return;
+
+	context->range.level[0].sens = secattr->attr.mls.lvl + 1;
+	context->range.level[1].sens = context->range.level[0].sens;
+}
+
+/**
+ * mls_export_netlbl_cat - Export the MLS categories to NetLabel
+ * @p: the policy
+ * @context: the security context
+ * @secattr: the NetLabel security attributes
+ *
+ * Description:
+ * Given the security context copy the low MLS categories into the NetLabel
+ * MLS category field.  Returns zero on success, negative values on failure.
+ *
+ */
+int mls_export_netlbl_cat(struct policydb *p, struct context *context,
+			  struct netlbl_lsm_secattr *secattr)
+{
+	int rc;
+
+	if (!p->mls_enabled)
+		return 0;
+
+	rc = ebitmap_netlbl_export(&context->range.level[0].cat,
+				   &secattr->attr.mls.cat);
+	if (rc == 0 && secattr->attr.mls.cat != NULL)
+		secattr->flags |= NETLBL_SECATTR_MLS_CAT;
+
+	return rc;
+}
+
+/**
+ * mls_import_netlbl_cat - Import the MLS categories from NetLabel
+ * @p: the policy
+ * @context: the security context
+ * @secattr: the NetLabel security attributes
+ *
+ * Description:
+ * Copy the NetLabel security attributes into the SELinux context; since the
+ * NetLabel security attribute only contains a single MLS category use it for
+ * both the low and high categories of the context.  Returns zero on success,
+ * negative values on failure.
+ *
+ */
+int mls_import_netlbl_cat(struct policydb *p, struct context *context,
+			  struct netlbl_lsm_secattr *secattr)
+{
+	int rc;
+
+	if (!p->mls_enabled)
+		return 0;
+
+	rc = ebitmap_netlbl_import(&context->range.level[0].cat,
+				   secattr->attr.mls.cat);
+	if (rc)
+		goto import_netlbl_cat_failure;
+	memcpy(&context->range.level[1].cat, &context->range.level[0].cat,
+	       sizeof(context->range.level[0].cat));
+
+	return 0;
+
+import_netlbl_cat_failure:
+	ebitmap_destroy(&context->range.level[0].cat);
+	return rc;
+}
+#endif /* CONFIG_NETLABEL */

linux-7.2.3/security/selinux/ss/mls.h

@@ -0,0 +1,96 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Multi-level security (MLS) policy operations.
+ *
+ * Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
+ */
+
+/*
+ * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
+ *          Support for enhanced MLS infrastructure.
+ *          Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
+ *
+ * Updated: Hewlett-Packard <paul@paul-moore.com>
+ *          Added support to import/export the MLS label from NetLabel
+ *          Copyright (X) Hewlett-Packard Development Company, L.P., 2006
+ */
+
+#ifndef _SS_MLS_H_
+#define _SS_MLS_H_
+
+#include <linux/jhash.h>
+
+#include "context.h"
+#include "ebitmap.h"
+#include "policydb.h"
+
+int mls_compute_context_len(struct policydb *p, struct context *context);
+void mls_sid_to_context(struct policydb *p, struct context *context,
+			char **scontext);
+bool mls_context_isvalid(const struct policydb *p, const struct context *c);
+bool mls_range_isvalid(const struct policydb *p, const struct mls_range *r);
+bool mls_level_isvalid(const struct policydb *p, const struct mls_level *l);
+
+int mls_context_to_sid(struct policydb *p, char oldc, char *scontext,
+		       struct context *context, struct sidtab *s, u32 def_sid);
+
+int mls_from_string(struct policydb *p, char *str, struct context *context,
+		    gfp_t gfp_mask);
+
+int mls_range_set(struct context *context, struct mls_range *range);
+
+int mls_convert_context(struct policydb *oldp, struct policydb *newp,
+			struct context *oldc, struct context *newc);
+
+int mls_compute_sid(struct policydb *p, struct context *scontext,
+		    struct context *tcontext, u16 tclass, u32 specified,
+		    struct context *newcontext, bool sock);
+
+int mls_setup_user_range(struct policydb *p, struct context *fromcon,
+			 struct user_datum *user, struct context *usercon);
+
+#ifdef CONFIG_NETLABEL
+void mls_export_netlbl_lvl(struct policydb *p, struct context *context,
+			   struct netlbl_lsm_secattr *secattr);
+void mls_import_netlbl_lvl(struct policydb *p, struct context *context,
+			   struct netlbl_lsm_secattr *secattr);
+int mls_export_netlbl_cat(struct policydb *p, struct context *context,
+			  struct netlbl_lsm_secattr *secattr);
+int mls_import_netlbl_cat(struct policydb *p, struct context *context,
+			  struct netlbl_lsm_secattr *secattr);
+#else
+static inline void mls_export_netlbl_lvl(struct policydb *p,
+					 struct context *context,
+					 struct netlbl_lsm_secattr *secattr)
+{
+	return;
+}
+static inline void mls_import_netlbl_lvl(struct policydb *p,
+					 struct context *context,
+					 struct netlbl_lsm_secattr *secattr)
+{
+	return;
+}
+static inline int mls_export_netlbl_cat(struct policydb *p,
+					struct context *context,
+					struct netlbl_lsm_secattr *secattr)
+{
+	return -ENOMEM;
+}
+static inline int mls_import_netlbl_cat(struct policydb *p,
+					struct context *context,
+					struct netlbl_lsm_secattr *secattr)
+{
+	return -ENOMEM;
+}
+#endif
+
+static inline u32 mls_range_hash(const struct mls_range *r, u32 hash)
+{
+	hash = jhash_2words(r->level[0].sens, r->level[1].sens, hash);
+	hash = ebitmap_hash(&r->level[0].cat, hash);
+	hash = ebitmap_hash(&r->level[1].cat, hash);
+	return hash;
+}
+
+#endif /* _SS_MLS_H */

linux-7.2.3/security/selinux/ss/mls_types.h

@@ -0,0 +1,52 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Type definitions for the multi-level security (MLS) policy.
+ *
+ * Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
+ */
+
+/*
+ * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
+ *          Support for enhanced MLS infrastructure.
+ *          Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
+ */
+
+#ifndef _SS_MLS_TYPES_H_
+#define _SS_MLS_TYPES_H_
+
+#include "security.h"
+#include "ebitmap.h"
+
+struct mls_level {
+	u32 sens; /* sensitivity */
+	struct ebitmap cat; /* category set */
+};
+
+struct mls_range {
+	struct mls_level level[2]; /* low == level[0], high == level[1] */
+};
+
+static inline int mls_level_eq(const struct mls_level *l1,
+			       const struct mls_level *l2)
+{
+	return ((l1->sens == l2->sens) && ebitmap_equal(&l1->cat, &l2->cat));
+}
+
+static inline int mls_level_dom(const struct mls_level *l1,
+				const struct mls_level *l2)
+{
+	return ((l1->sens >= l2->sens) &&
+		ebitmap_contains(&l1->cat, &l2->cat, 0));
+}
+
+#define mls_level_incomp(l1, l2) \
+	(!mls_level_dom((l1), (l2)) && !mls_level_dom((l2), (l1)))
+
+#define mls_level_between(l1, l2, l3) \
+	(mls_level_dom((l1), (l2)) && mls_level_dom((l3), (l1)))
+
+#define mls_range_contains(r1, r2)                        \
+	(mls_level_dom(&(r2).level[0], &(r1).level[0]) && \
+	 mls_level_dom(&(r1).level[1], &(r2).level[1]))
+
+#endif /* _SS_MLS_TYPES_H_ */

linux-7.2.3/security/selinux/ss/policydb.h

@@ -0,0 +1,428 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * A policy database (policydb) specifies the
+ * configuration data for the security policy.
+ *
+ * Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
+ */
+
+/*
+ * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
+ *          Support for enhanced MLS infrastructure.
+ *          Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
+ *
+ * Updated: Frank Mayer <mayerf@tresys.com> and
+ *          Karl MacMillan <kmacmillan@tresys.com>
+ *          Added conditional policy language extensions
+ *          Copyright (C) 2003-2004 Tresys Technology, LLC
+ */
+
+#ifndef _SS_POLICYDB_H_
+#define _SS_POLICYDB_H_
+
+#include "symtab.h"
+#include "avtab.h"
+#include "sidtab.h"
+#include "ebitmap.h"
+#include "mls_types.h"
+#include "context.h"
+#include "constraint.h"
+
+/*
+ * A datum type is defined for each kind of symbol
+ * in the configuration data:  individual permissions,
+ * common prefixes for access vectors, classes,
+ * users, roles, types, sensitivities, categories, etc.
+ */
+
+/* Permission attributes */
+struct perm_datum {
+	u32 value; /* permission bit + 1 */
+};
+
+/* Attributes of a common prefix for access vectors */
+struct common_datum {
+	u32 value; /* internal common value */
+	struct symtab permissions; /* common permissions */
+};
+
+/* Class attributes */
+struct class_datum {
+	u16 value; /* class value */
+	char *comkey; /* common name */
+	struct common_datum *comdatum; /* common datum */
+	struct symtab permissions; /* class-specific permission symbol table */
+	struct constraint_node *constraints; /* constraints on class perms */
+	struct constraint_node *validatetrans; /* special transition rules */
+/* Options how a new object user, role, and type should be decided */
+#define DEFAULT_SOURCE 1
+#define DEFAULT_TARGET 2
+	char default_user;
+	char default_role;
+	char default_type;
+/* Options how a new object range should be decided */
+#define DEFAULT_SOURCE_LOW	1
+#define DEFAULT_SOURCE_HIGH	2
+#define DEFAULT_SOURCE_LOW_HIGH 3
+#define DEFAULT_TARGET_LOW	4
+#define DEFAULT_TARGET_HIGH	5
+#define DEFAULT_TARGET_LOW_HIGH 6
+#define DEFAULT_GLBLUB		7
+	char default_range;
+};
+
+/* Role attributes */
+struct role_datum {
+	u32 value; /* internal role value */
+	u32 bounds; /* boundary of role, 0 for none */
+	struct ebitmap dominates; /* set of roles dominated by this role */
+	struct ebitmap types; /* set of authorized types for role */
+};
+
+struct role_trans_key {
+	u32 role; /* current role */
+	u32 type; /* program executable type, or new object type */
+	u16 tclass; /* process class, or new object class */
+};
+
+struct role_trans_datum {
+	u32 new_role; /* new role */
+};
+
+struct filename_trans_key {
+	u32 ttype; /* parent dir context */
+	u16 tclass; /* class of new object */
+	const char *name; /* last path component */
+};
+
+struct filename_trans_datum {
+	struct ebitmap stypes; /* bitmap of source types for this otype */
+	u32 otype; /* resulting type of new object */
+	struct filename_trans_datum *next; /* record for next otype*/
+};
+
+struct role_allow {
+	u32 role; /* current role */
+	u32 new_role; /* new role */
+	struct role_allow *next;
+};
+
+/* Type attributes */
+struct type_datum {
+	u32 value; /* internal type value */
+	u32 bounds; /* boundary of type, 0 for none */
+	/* internally unused, only forwarded via policydb_write() */
+	unsigned char primary; /* primary name? */
+	unsigned char attribute; /* attribute ?*/
+};
+
+/* User attributes */
+struct user_datum {
+	u32 value; /* internal user value */
+	u32 bounds; /* bounds of user, 0 for none */
+	struct ebitmap roles; /* set of authorized roles for user */
+	struct mls_range range; /* MLS range (min - max) for user */
+	struct mls_level dfltlevel; /* default login MLS level for user */
+};
+
+/* Sensitivity attributes */
+struct level_datum {
+	struct mls_level level; /* sensitivity and associated categories */
+	unsigned char isalias; /* is this sensitivity an alias for another? */
+};
+
+/* Category attributes */
+struct cat_datum {
+	u32 value; /* internal category bit + 1 */
+	unsigned char isalias; /* is this category an alias for another? */
+};
+
+struct range_trans {
+	u32 source_type;
+	u32 target_type;
+	u16 target_class;
+};
+
+/* Boolean data type */
+struct cond_bool_datum {
+	u32 value; /* internal type value */
+	int state;
+};
+
+struct cond_node;
+
+/*
+ * type set preserves data needed to determine constraint info from
+ * policy source. This is not used by the kernel policy but allows
+ * utilities such as audit2allow to determine constraint denials.
+ */
+struct type_set {
+	struct ebitmap types;
+	struct ebitmap negset;
+	u32 flags;
+};
+
+/*
+ * The configuration data includes security contexts for
+ * initial SIDs, unlabeled file systems, TCP and UDP port numbers,
+ * network interfaces, and nodes.  This structure stores the
+ * relevant data for one such entry.  Entries of the same kind
+ * (e.g. all initial SIDs) are linked together into a list.
+ */
+struct ocontext {
+	union {
+		char *name; /* name of initial SID, fs, netif, fstype, path */
+		struct {
+			u8 protocol;
+			u16 low_port;
+			u16 high_port;
+		} port; /* TCP or UDP port information */
+		struct {
+			u32 addr;
+			u32 mask;
+		} node; /* node information */
+		struct {
+			u32 addr[4];
+			u32 mask[4];
+		} node6; /* IPv6 node information */
+		struct {
+			u64 subnet_prefix;
+			u16 low_pkey;
+			u16 high_pkey;
+		} ibpkey;
+		struct {
+			char *dev_name;
+			u8 port;
+		} ibendport;
+	} u;
+	union {
+		u16 sclass; /* security class for genfs (can be 0 for wildcard) */
+		u32 behavior; /* labeling behavior for fs_use */
+	} v;
+	struct context context[2]; /* security context(s) */
+	u32 sid[2]; /* SID(s) */
+	struct ocontext *next;
+};
+
+struct genfs {
+	char *fstype;
+	struct ocontext *head;
+	struct genfs *next;
+};
+
+/* symbol table array indices */
+#define SYM_COMMONS 0
+#define SYM_CLASSES 1
+#define SYM_ROLES   2
+#define SYM_TYPES   3
+#define SYM_USERS   4
+#define SYM_BOOLS   5
+#define SYM_LEVELS  6
+#define SYM_CATS    7
+#define SYM_NUM	    8
+
+/* object context array indices */
+#define OCON_ISID      0 /* initial SIDs */
+#define OCON_FS	       1 /* unlabeled file systems (deprecated) */
+#define OCON_PORT      2 /* TCP and UDP port numbers */
+#define OCON_NETIF     3 /* network interfaces */
+#define OCON_NODE      4 /* nodes */
+#define OCON_FSUSE     5 /* fs_use */
+#define OCON_NODE6     6 /* IPv6 nodes */
+#define OCON_IBPKEY    7 /* Infiniband PKeys */
+#define OCON_IBENDPORT 8 /* Infiniband end ports */
+#define OCON_NUM       9
+
+/* The policy database */
+struct policydb {
+	int mls_enabled;
+
+	/* symbol tables */
+	struct symtab symtab[SYM_NUM];
+#define p_commons symtab[SYM_COMMONS]
+#define p_classes symtab[SYM_CLASSES]
+#define p_roles	  symtab[SYM_ROLES]
+#define p_types	  symtab[SYM_TYPES]
+#define p_users	  symtab[SYM_USERS]
+#define p_bools	  symtab[SYM_BOOLS]
+#define p_levels  symtab[SYM_LEVELS]
+#define p_cats	  symtab[SYM_CATS]
+
+	/* symbol names indexed by (value - 1) */
+	char **sym_val_to_name[SYM_NUM];
+
+	/* class, role, and user attributes indexed by (value - 1) */
+	struct class_datum **class_val_to_struct;
+	struct role_datum **role_val_to_struct;
+	struct user_datum **user_val_to_struct;
+	struct type_datum **type_val_to_struct;
+
+	/* type enforcement access vectors and transitions */
+	struct avtab te_avtab;
+
+	/* role transitions */
+	struct hashtab role_tr;
+
+	/* file transitions with the last path component */
+	/* quickly exclude lookups when parent ttype has no rules */
+	struct ebitmap filename_trans_ttypes;
+	/* actual set of filename_trans rules */
+	struct hashtab filename_trans;
+	/* only used if policyvers < POLICYDB_VERSION_COMP_FTRANS */
+	u32 compat_filename_trans_count;
+
+	/* bools indexed by (value - 1) */
+	struct cond_bool_datum **bool_val_to_struct;
+	/* type enforcement conditional access vectors and transitions */
+	struct avtab te_cond_avtab;
+	/* array indexing te_cond_avtab by conditional */
+	struct cond_node *cond_list;
+	u32 cond_list_len;
+
+	/* role allows */
+	struct role_allow *role_allow;
+
+	/* security contexts of initial SIDs, unlabeled file systems,
+	   TCP or UDP port numbers, network interfaces and nodes */
+	struct ocontext *ocontexts[OCON_NUM];
+
+	/* security contexts for files in filesystems that cannot support
+	   a persistent label mapping or use another
+	   fixed labeling behavior. */
+	struct genfs *genfs;
+
+	/* range transitions table (range_trans_key -> mls_range) */
+	struct hashtab range_tr;
+
+	/* type -> attribute reverse mapping */
+	struct ebitmap *type_attr_map_array;
+
+	struct ebitmap policycaps;
+
+	struct ebitmap permissive_map;
+
+	struct ebitmap neveraudit_map;
+
+	/* length of this policy when it was loaded */
+	size_t len;
+
+	unsigned int policyvers;
+
+	unsigned int reject_unknown : 1;
+	unsigned int allow_unknown : 1;
+
+	u16 process_class;
+	u32 process_trans_perms;
+} __randomize_layout;
+
+struct policy_file {
+	char *data;
+	size_t len;
+};
+
+extern void policydb_destroy(struct policydb *p);
+extern int policydb_load_isids(struct policydb *p, struct sidtab *s);
+extern bool policydb_context_isvalid(const struct policydb *p,
+				     const struct context *c);
+extern bool policydb_class_isvalid(const struct policydb *p, u16 class);
+extern bool policydb_type_isvalid(const struct policydb *p, u32 type);
+extern bool policydb_simpletype_isvalid(const struct policydb *p, u32 type);
+extern bool policydb_role_isvalid(const struct policydb *p, u32 role);
+extern bool policydb_user_isvalid(const struct policydb *p, u32 user);
+extern int policydb_read(struct policydb *p, struct policy_file *fp);
+extern int policydb_write(struct policydb *p, struct policy_file *fp);
+
+extern struct filename_trans_datum *
+policydb_filenametr_search(struct policydb *p, struct filename_trans_key *key);
+
+extern struct mls_range *policydb_rangetr_search(struct policydb *p,
+						 struct range_trans *key);
+
+extern struct role_trans_datum *
+policydb_roletr_search(struct policydb *p, struct role_trans_key *key);
+
+#define POLICYDB_CONFIG_MLS 1
+
+/* the config flags related to unknown classes/perms are bits 2 and 3 */
+#define REJECT_UNKNOWN 0x00000002
+#define ALLOW_UNKNOWN  0x00000004
+
+#define OBJECT_R     "object_r"
+#define OBJECT_R_VAL 1
+
+#define POLICYDB_MAGIC	SELINUX_MAGIC
+#define POLICYDB_STRING "SE Linux"
+
+struct policy_data {
+	struct policydb *p;
+	struct policy_file *fp;
+};
+
+static inline int size_check(size_t bytes, size_t num,
+			     const struct policy_file *fp)
+{
+	size_t len;
+
+	if (unlikely(check_mul_overflow(bytes, num, &len)))
+		return -EINVAL;
+
+	if (unlikely(len > fp->len))
+		return -EINVAL;
+
+	return 0;
+}
+
+static inline int next_entry(void *buf, struct policy_file *fp, size_t bytes)
+{
+	if (bytes > fp->len)
+		return -EINVAL;
+
+	memcpy(buf, fp->data, bytes);
+	fp->data += bytes;
+	fp->len -= bytes;
+	return 0;
+}
+
+static inline int put_entry(const void *buf, size_t bytes, size_t num,
+			    struct policy_file *fp)
+{
+	size_t len;
+
+	if (unlikely(check_mul_overflow(bytes, num, &len)))
+		return -EINVAL;
+
+	if (len > fp->len)
+		return -EINVAL;
+	memcpy(fp->data, buf, len);
+	fp->data += len;
+	fp->len -= len;
+
+	return 0;
+}
+
+static inline const char *sym_name(const struct policydb *p, unsigned int sym_num,
+			     unsigned int element_nr)
+{
+	return p->sym_val_to_name[sym_num][element_nr];
+}
+
+static inline bool val_is_boolean(u32 value)
+{
+	return value == 0 || value == 1;
+}
+
+extern int str_read(char **strp, gfp_t flags, struct policy_file *fp, u32 len);
+
+extern u16 string_to_security_class(struct policydb *p, const char *name);
+extern u32 string_to_av_perm(struct policydb *p, u16 tclass, const char *name);
+
+#define pr_warn_once_policyload(policy, fmt, ...)    \
+	do {                                         \
+		static const void *prev_policy__;    \
+		if (prev_policy__ != policy) {       \
+			pr_warn(fmt, ##__VA_ARGS__); \
+			prev_policy__ = policy;      \
+		}                                    \
+	} while (0)
+
+#endif /* _SS_POLICYDB_H_ */

linux-7.2.3/security/selinux/ss/services.h

@@ -0,0 +1,47 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Implementation of the security services.
+ *
+ * Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
+ */
+
+#ifndef _SS_SERVICES_H_
+#define _SS_SERVICES_H_
+
+#include "policydb.h"
+
+/* Mapping for a single class */
+struct selinux_mapping {
+	u16 value; /* policy value for class */
+	u16 num_perms; /* number of permissions in class */
+	u32 perms[sizeof(u32) * 8]; /* policy values for permissions */
+};
+
+/* Map for all of the classes, with array size */
+struct selinux_map {
+	struct selinux_mapping *mapping; /* indexed by class */
+	u16 size; /* array size of mapping */
+};
+
+struct selinux_policy {
+	struct sidtab *sidtab;
+	struct policydb policydb;
+	struct selinux_map map;
+	u32 latest_granting;
+} __randomize_layout;
+
+struct convert_context_args {
+	struct policydb *oldp;
+	struct policydb *newp;
+};
+
+void services_compute_xperms_drivers(struct extended_perms *xperms,
+				     struct avtab_node *node);
+void services_compute_xperms_decision(struct extended_perms_decision *xpermd,
+				      struct avtab_node *node);
+
+int services_convert_context(struct convert_context_args *args,
+			     struct context *oldc, struct context *newc,
+			     gfp_t gfp_flags);
+
+#endif /* _SS_SERVICES_H_ */

linux-7.2.3/security/selinux/ss/sidtab.c

@@ -0,0 +1,638 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Implementation of the SID table type.
+ *
+ * Original author: Stephen Smalley, <stephen.smalley.work@gmail.com>
+ * Author: Ondrej Mosnacek, <omosnacek@gmail.com>
+ *
+ * Copyright (C) 2018 Red Hat, Inc.
+ */
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/rcupdate.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+#include <asm/barrier.h>
+#include "flask.h"
+#include "security.h"
+#include "sidtab.h"
+#include "services.h"
+
+struct sidtab_str_cache {
+	struct rcu_head rcu_member;
+	struct list_head lru_member;
+	struct sidtab_entry *parent;
+	u32 len;
+	char str[] __counted_by(len);
+};
+
+#define index_to_sid(index) ((index) + SECINITSID_NUM + 1)
+#define sid_to_index(sid)   ((sid) - (SECINITSID_NUM + 1))
+
+int sidtab_init(struct sidtab *s)
+{
+	u32 i;
+
+	memset(s->roots, 0, sizeof(s->roots));
+
+	for (i = 0; i < SECINITSID_NUM; i++)
+		s->isids[i].set = 0;
+
+	s->frozen = false;
+	s->count = 0;
+	s->convert = NULL;
+	hash_init(s->context_to_sid);
+
+	spin_lock_init(&s->lock);
+
+#if CONFIG_SECURITY_SELINUX_SID2STR_CACHE_SIZE > 0
+	s->cache_free_slots = CONFIG_SECURITY_SELINUX_SID2STR_CACHE_SIZE;
+	INIT_LIST_HEAD(&s->cache_lru_list);
+	spin_lock_init(&s->cache_lock);
+#endif
+
+	return 0;
+}
+
+static u32 context_to_sid(struct sidtab *s, struct context *context, u32 hash)
+{
+	struct sidtab_entry *entry;
+	u32 sid = 0;
+
+	rcu_read_lock();
+	hash_for_each_possible_rcu(s->context_to_sid, entry, list, hash) {
+		if (entry->hash != hash)
+			continue;
+		if (context_equal(&entry->context, context)) {
+			sid = entry->sid;
+			break;
+		}
+	}
+	rcu_read_unlock();
+	return sid;
+}
+
+int sidtab_set_initial(struct sidtab *s, u32 sid, struct context *context)
+{
+	struct sidtab_isid_entry *isid;
+	u32 hash;
+	int rc;
+
+	if (sid == 0 || sid > SECINITSID_NUM)
+		return -EINVAL;
+
+	isid = &s->isids[sid - 1];
+
+	rc = context_cpy(&isid->entry.context, context);
+	if (rc)
+		return rc;
+
+#if CONFIG_SECURITY_SELINUX_SID2STR_CACHE_SIZE > 0
+	isid->entry.cache = NULL;
+#endif
+	isid->set = 1;
+
+	hash = context_compute_hash(context);
+
+	/*
+	 * Multiple initial sids may map to the same context. Check that this
+	 * context is not already represented in the context_to_sid hashtable
+	 * to avoid duplicate entries and long linked lists upon hash
+	 * collision.
+	 */
+	if (!context_to_sid(s, context, hash)) {
+		isid->entry.sid = sid;
+		isid->entry.hash = hash;
+		hash_add(s->context_to_sid, &isid->entry.list, hash);
+	}
+
+	return 0;
+}
+
+int sidtab_hash_stats(struct sidtab *sidtab, char *page)
+{
+	unsigned int i;
+	int chain_len = 0;
+	int slots_used = 0;
+	int entries = 0;
+	int max_chain_len = 0;
+	unsigned int cur_bucket = 0;
+	struct sidtab_entry *entry;
+
+	rcu_read_lock();
+	hash_for_each_rcu(sidtab->context_to_sid, i, entry, list) {
+		entries++;
+		if (i == cur_bucket) {
+			chain_len++;
+			if (chain_len == 1)
+				slots_used++;
+		} else {
+			cur_bucket = i;
+			if (chain_len > max_chain_len)
+				max_chain_len = chain_len;
+			chain_len = 0;
+		}
+	}
+	rcu_read_unlock();
+
+	if (chain_len > max_chain_len)
+		max_chain_len = chain_len;
+
+	return scnprintf(page, PAGE_SIZE,
+			 "entries: %d\nbuckets used: %d/%d\n"
+			 "longest chain: %d\n",
+			 entries, slots_used, SIDTAB_HASH_BUCKETS,
+			 max_chain_len);
+}
+
+static u32 sidtab_level_from_count(u32 count)
+{
+	u32 capacity = SIDTAB_LEAF_ENTRIES;
+	u32 level = 0;
+
+	while (count > capacity) {
+		capacity <<= SIDTAB_INNER_SHIFT;
+		++level;
+	}
+	return level;
+}
+
+static int sidtab_alloc_roots(struct sidtab *s, u32 level)
+{
+	u32 l;
+
+	if (!s->roots[0].ptr_leaf) {
+		s->roots[0].ptr_leaf =
+			kzalloc(SIDTAB_NODE_ALLOC_SIZE, GFP_ATOMIC);
+		if (!s->roots[0].ptr_leaf)
+			return -ENOMEM;
+	}
+	for (l = 1; l <= level; ++l)
+		if (!s->roots[l].ptr_inner) {
+			s->roots[l].ptr_inner =
+				kzalloc(SIDTAB_NODE_ALLOC_SIZE, GFP_ATOMIC);
+			if (!s->roots[l].ptr_inner)
+				return -ENOMEM;
+			s->roots[l].ptr_inner->entries[0] = s->roots[l - 1];
+		}
+	return 0;
+}
+
+static struct sidtab_entry *sidtab_do_lookup(struct sidtab *s, u32 index,
+					     int alloc)
+{
+	union sidtab_entry_inner *entry;
+	u32 level, capacity_shift, leaf_index = index / SIDTAB_LEAF_ENTRIES;
+
+	/* find the level of the subtree we need */
+	level = sidtab_level_from_count(index + 1);
+	capacity_shift = level * SIDTAB_INNER_SHIFT;
+
+	/* allocate roots if needed */
+	if (alloc && sidtab_alloc_roots(s, level) != 0)
+		return NULL;
+
+	/* lookup inside the subtree */
+	entry = &s->roots[level];
+	while (level != 0) {
+		capacity_shift -= SIDTAB_INNER_SHIFT;
+		--level;
+
+		entry = &entry->ptr_inner->entries[leaf_index >> capacity_shift];
+		leaf_index &= ((u32)1 << capacity_shift) - 1;
+
+		if (!entry->ptr_inner) {
+			if (alloc)
+				entry->ptr_inner = kzalloc(
+					SIDTAB_NODE_ALLOC_SIZE, GFP_ATOMIC);
+			if (!entry->ptr_inner)
+				return NULL;
+		}
+	}
+	if (!entry->ptr_leaf) {
+		if (alloc)
+			entry->ptr_leaf =
+				kzalloc(SIDTAB_NODE_ALLOC_SIZE, GFP_ATOMIC);
+		if (!entry->ptr_leaf)
+			return NULL;
+	}
+	return &entry->ptr_leaf->entries[index % SIDTAB_LEAF_ENTRIES];
+}
+
+static struct sidtab_entry *sidtab_lookup(struct sidtab *s, u32 index)
+{
+	/* read entries only after reading count */
+	u32 count = smp_load_acquire(&s->count);
+
+	if (index >= count)
+		return NULL;
+
+	return sidtab_do_lookup(s, index, 0);
+}
+
+static struct sidtab_entry *sidtab_lookup_initial(struct sidtab *s, u32 sid)
+{
+	return s->isids[sid - 1].set ? &s->isids[sid - 1].entry : NULL;
+}
+
+static struct sidtab_entry *sidtab_search_core(struct sidtab *s, u32 sid,
+					       int force)
+{
+	if (sid != 0) {
+		struct sidtab_entry *entry;
+
+		if (sid > SECINITSID_NUM)
+			entry = sidtab_lookup(s, sid_to_index(sid));
+		else
+			entry = sidtab_lookup_initial(s, sid);
+		if (entry && (!entry->context.len || force))
+			return entry;
+	}
+
+	return sidtab_lookup_initial(s, SECINITSID_UNLABELED);
+}
+
+struct sidtab_entry *sidtab_search_entry(struct sidtab *s, u32 sid)
+{
+	return sidtab_search_core(s, sid, 0);
+}
+
+struct sidtab_entry *sidtab_search_entry_force(struct sidtab *s, u32 sid)
+{
+	return sidtab_search_core(s, sid, 1);
+}
+
+int sidtab_context_to_sid(struct sidtab *s, struct context *context, u32 *sid)
+{
+	unsigned long flags;
+	u32 count, hash = context_compute_hash(context);
+	struct sidtab_convert_params *convert;
+	struct sidtab_entry *dst, *dst_convert;
+	int rc;
+
+	*sid = context_to_sid(s, context, hash);
+	if (*sid)
+		return 0;
+
+	/* lock-free search failed: lock, re-search, and insert if not found */
+	spin_lock_irqsave(&s->lock, flags);
+
+	rc = 0;
+	*sid = context_to_sid(s, context, hash);
+	if (*sid)
+		goto out_unlock;
+
+	if (unlikely(s->frozen)) {
+		/*
+		 * This sidtab is now frozen - tell the caller to abort and
+		 * get the new one.
+		 */
+		rc = -ESTALE;
+		goto out_unlock;
+	}
+
+	count = s->count;
+
+	/* bail out if we already reached max entries */
+	rc = -EOVERFLOW;
+	if (count >= SIDTAB_MAX)
+		goto out_unlock;
+
+	/* insert context into new entry */
+	rc = -ENOMEM;
+	dst = sidtab_do_lookup(s, count, 1);
+	if (!dst)
+		goto out_unlock;
+
+	dst->sid = index_to_sid(count);
+	dst->hash = hash;
+
+	rc = context_cpy(&dst->context, context);
+	if (rc)
+		goto out_unlock;
+
+	/*
+	 * if we are building a new sidtab, we need to convert the context
+	 * and insert it there as well
+	 */
+	convert = s->convert;
+	if (convert) {
+		struct sidtab *target = convert->target;
+
+		rc = -ENOMEM;
+		dst_convert = sidtab_do_lookup(target, count, 1);
+		if (!dst_convert) {
+			context_destroy(&dst->context);
+			goto out_unlock;
+		}
+
+		rc = services_convert_context(convert->args, context,
+					      &dst_convert->context,
+					      GFP_ATOMIC);
+		if (rc) {
+			context_destroy(&dst->context);
+			goto out_unlock;
+		}
+		dst_convert->sid = index_to_sid(count);
+		dst_convert->hash = context_compute_hash(&dst_convert->context);
+		target->count = count + 1;
+
+		hash_add_rcu(target->context_to_sid, &dst_convert->list,
+			     dst_convert->hash);
+	}
+
+	if (context->len)
+		pr_info("SELinux:  Context %s is not valid (left unmapped).\n",
+			context->str);
+
+	*sid = index_to_sid(count);
+
+	/* write entries before updating count */
+	smp_store_release(&s->count, count + 1);
+	hash_add_rcu(s->context_to_sid, &dst->list, dst->hash);
+
+	rc = 0;
+out_unlock:
+	spin_unlock_irqrestore(&s->lock, flags);
+	return rc;
+}
+
+static void sidtab_convert_hashtable(struct sidtab *s, u32 count)
+{
+	struct sidtab_entry *entry;
+	u32 i;
+
+	for (i = 0; i < count; i++) {
+		entry = sidtab_do_lookup(s, i, 0);
+		entry->sid = index_to_sid(i);
+		entry->hash = context_compute_hash(&entry->context);
+
+		hash_add_rcu(s->context_to_sid, &entry->list, entry->hash);
+	}
+}
+
+static int sidtab_convert_tree(union sidtab_entry_inner *edst,
+			       union sidtab_entry_inner *esrc, u32 *pos,
+			       u32 count, u32 level,
+			       struct sidtab_convert_params *convert)
+{
+	int rc;
+	u32 i;
+
+	if (level != 0) {
+		if (!edst->ptr_inner) {
+			edst->ptr_inner =
+				kzalloc(SIDTAB_NODE_ALLOC_SIZE, GFP_KERNEL);
+			if (!edst->ptr_inner)
+				return -ENOMEM;
+		}
+		i = 0;
+		while (i < SIDTAB_INNER_ENTRIES && *pos < count) {
+			rc = sidtab_convert_tree(&edst->ptr_inner->entries[i],
+						 &esrc->ptr_inner->entries[i],
+						 pos, count, level - 1,
+						 convert);
+			if (rc)
+				return rc;
+			i++;
+		}
+	} else {
+		if (!edst->ptr_leaf) {
+			edst->ptr_leaf =
+				kzalloc(SIDTAB_NODE_ALLOC_SIZE, GFP_KERNEL);
+			if (!edst->ptr_leaf)
+				return -ENOMEM;
+		}
+		i = 0;
+		while (i < SIDTAB_LEAF_ENTRIES && *pos < count) {
+			rc = services_convert_context(
+				convert->args,
+				&esrc->ptr_leaf->entries[i].context,
+				&edst->ptr_leaf->entries[i].context,
+				GFP_KERNEL);
+			if (rc)
+				return rc;
+			(*pos)++;
+			i++;
+		}
+		cond_resched();
+	}
+	return 0;
+}
+
+int sidtab_convert(struct sidtab *s, struct sidtab_convert_params *params)
+{
+	unsigned long flags;
+	u32 count, level, pos;
+	int rc;
+
+	spin_lock_irqsave(&s->lock, flags);
+
+	/* concurrent policy loads are not allowed */
+	if (s->convert) {
+		spin_unlock_irqrestore(&s->lock, flags);
+		return -EBUSY;
+	}
+
+	count = s->count;
+	level = sidtab_level_from_count(count);
+
+	/* allocate last leaf in the new sidtab (to avoid race with
+	 * live convert)
+	 */
+	rc = sidtab_do_lookup(params->target, count - 1, 1) ? 0 : -ENOMEM;
+	if (rc) {
+		spin_unlock_irqrestore(&s->lock, flags);
+		return rc;
+	}
+
+	/* set count in case no new entries are added during conversion */
+	params->target->count = count;
+
+	/* enable live convert of new entries */
+	s->convert = params;
+
+	/* we can safely convert the tree outside the lock */
+	spin_unlock_irqrestore(&s->lock, flags);
+
+	pr_info("SELinux:  Converting %u SID table entries...\n", count);
+
+	/* convert all entries not covered by live convert */
+	pos = 0;
+	rc = sidtab_convert_tree(&params->target->roots[level],
+				 &s->roots[level], &pos, count, level, params);
+	if (rc) {
+		/* we need to keep the old table - disable live convert */
+		spin_lock_irqsave(&s->lock, flags);
+		s->convert = NULL;
+		spin_unlock_irqrestore(&s->lock, flags);
+		return rc;
+	}
+	/*
+	 * The hashtable can also be modified in sidtab_context_to_sid()
+	 * so we must re-acquire the lock here.
+	 */
+	spin_lock_irqsave(&s->lock, flags);
+	sidtab_convert_hashtable(params->target, count);
+	spin_unlock_irqrestore(&s->lock, flags);
+
+	return 0;
+}
+
+void sidtab_cancel_convert(struct sidtab *s)
+{
+	unsigned long flags;
+
+	/* cancelling policy load - disable live convert of sidtab */
+	spin_lock_irqsave(&s->lock, flags);
+	s->convert = NULL;
+	spin_unlock_irqrestore(&s->lock, flags);
+}
+
+void sidtab_freeze_begin(struct sidtab *s, unsigned long *flags)
+	__acquires(&s->lock)
+{
+	spin_lock_irqsave(&s->lock, *flags);
+	s->frozen = true;
+	s->convert = NULL;
+}
+void sidtab_freeze_end(struct sidtab *s, unsigned long *flags)
+	__releases(&s->lock)
+{
+	spin_unlock_irqrestore(&s->lock, *flags);
+}
+
+static void sidtab_destroy_entry(struct sidtab_entry *entry)
+{
+	context_destroy(&entry->context);
+#if CONFIG_SECURITY_SELINUX_SID2STR_CACHE_SIZE > 0
+	kfree(rcu_dereference_raw(entry->cache));
+#endif
+}
+
+static void sidtab_destroy_tree(union sidtab_entry_inner entry, u32 level)
+{
+	u32 i;
+
+	if (level != 0) {
+		struct sidtab_node_inner *node = entry.ptr_inner;
+
+		if (!node)
+			return;
+
+		for (i = 0; i < SIDTAB_INNER_ENTRIES; i++)
+			sidtab_destroy_tree(node->entries[i], level - 1);
+		kfree(node);
+	} else {
+		struct sidtab_node_leaf *node = entry.ptr_leaf;
+
+		if (!node)
+			return;
+
+		for (i = 0; i < SIDTAB_LEAF_ENTRIES; i++)
+			sidtab_destroy_entry(&node->entries[i]);
+		kfree(node);
+	}
+}
+
+void sidtab_destroy(struct sidtab *s)
+{
+	u32 i, level;
+
+	for (i = 0; i < SECINITSID_NUM; i++)
+		if (s->isids[i].set)
+			sidtab_destroy_entry(&s->isids[i].entry);
+
+	level = SIDTAB_MAX_LEVEL;
+	while (level && !s->roots[level].ptr_inner)
+		--level;
+
+	sidtab_destroy_tree(s->roots[level], level);
+	/*
+	 * The context_to_sid hashtable's objects are all shared
+	 * with the isids array and context tree, and so don't need
+	 * to be cleaned up here.
+	 */
+}
+
+#if CONFIG_SECURITY_SELINUX_SID2STR_CACHE_SIZE > 0
+
+void sidtab_sid2str_put(struct sidtab *s, struct sidtab_entry *entry,
+			const char *str, u32 str_len)
+{
+	struct sidtab_str_cache *cache, *victim = NULL;
+	unsigned long flags;
+
+	/* do not cache invalid contexts */
+	if (entry->context.len)
+		return;
+
+	spin_lock_irqsave(&s->cache_lock, flags);
+
+	cache = rcu_dereference_protected(entry->cache,
+					  lockdep_is_held(&s->cache_lock));
+	if (cache) {
+		/* entry in cache - just bump to the head of LRU list */
+		list_move(&cache->lru_member, &s->cache_lru_list);
+		goto out_unlock;
+	}
+
+	cache = kmalloc_flex(*cache, str, str_len, GFP_ATOMIC);
+	if (!cache)
+		goto out_unlock;
+
+	if (s->cache_free_slots == 0) {
+		/* pop a cache entry from the tail and free it */
+		victim = container_of(s->cache_lru_list.prev,
+				      struct sidtab_str_cache, lru_member);
+		list_del(&victim->lru_member);
+		rcu_assign_pointer(victim->parent->cache, NULL);
+	} else {
+		s->cache_free_slots--;
+	}
+	cache->parent = entry;
+	cache->len = str_len;
+	memcpy(cache->str, str, str_len);
+	list_add(&cache->lru_member, &s->cache_lru_list);
+
+	rcu_assign_pointer(entry->cache, cache);
+
+out_unlock:
+	spin_unlock_irqrestore(&s->cache_lock, flags);
+	kfree_rcu(victim, rcu_member);
+}
+
+int sidtab_sid2str_get(struct sidtab *s, struct sidtab_entry *entry, char **out,
+		       u32 *out_len)
+{
+	struct sidtab_str_cache *cache;
+	int rc = 0;
+
+	if (entry->context.len)
+		return -ENOENT; /* do not cache invalid contexts */
+
+	rcu_read_lock();
+
+	cache = rcu_dereference(entry->cache);
+	if (!cache) {
+		rc = -ENOENT;
+	} else {
+		*out_len = cache->len;
+		if (out) {
+			*out = kmemdup(cache->str, cache->len, GFP_ATOMIC);
+			if (!*out)
+				rc = -ENOMEM;
+		}
+	}
+
+	rcu_read_unlock();
+
+	if (!rc && out)
+		sidtab_sid2str_put(s, entry, *out, *out_len);
+	return rc;
+}
+
+#endif /* CONFIG_SECURITY_SELINUX_SID2STR_CACHE_SIZE > 0 */

linux-7.2.3/security/selinux/ss/sidtab.h

@@ -0,0 +1,160 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * A security identifier table (sidtab) is a lookup table
+ * of security context structures indexed by SID value.
+ *
+ * Original author: Stephen Smalley, <stephen.smalley.work@gmail.com>
+ * Author: Ondrej Mosnacek, <omosnacek@gmail.com>
+ *
+ * Copyright (C) 2018 Red Hat, Inc.
+ */
+
+#ifndef _SS_SIDTAB_H_
+#define _SS_SIDTAB_H_
+
+#include <linux/spinlock_types.h>
+#include <linux/log2.h>
+#include <linux/hashtable.h>
+
+#include "context.h"
+
+struct sidtab_entry {
+	u32 sid;
+	u32 hash;
+	struct context context;
+#if CONFIG_SECURITY_SELINUX_SID2STR_CACHE_SIZE > 0
+	struct sidtab_str_cache __rcu *cache;
+#endif
+	struct hlist_node list;
+};
+
+union sidtab_entry_inner {
+	struct sidtab_node_inner *ptr_inner;
+	struct sidtab_node_leaf *ptr_leaf;
+};
+
+/* align node size to page boundary */
+#define SIDTAB_NODE_ALLOC_SHIFT PAGE_SHIFT
+#define SIDTAB_NODE_ALLOC_SIZE	PAGE_SIZE
+
+#define size_to_shift(size) ((size) == 1 ? 1 : (const_ilog2((size)-1) + 1))
+
+#define SIDTAB_INNER_SHIFT         \
+	(SIDTAB_NODE_ALLOC_SHIFT - \
+	 size_to_shift(sizeof(union sidtab_entry_inner)))
+#define SIDTAB_INNER_ENTRIES ((size_t)1 << SIDTAB_INNER_SHIFT)
+#define SIDTAB_LEAF_ENTRIES \
+	(SIDTAB_NODE_ALLOC_SIZE / sizeof(struct sidtab_entry))
+
+#define SIDTAB_MAX_BITS 32
+#define SIDTAB_MAX	U32_MAX
+/* ensure enough tree levels for SIDTAB_MAX entries */
+#define SIDTAB_MAX_LEVEL                                                   \
+	DIV_ROUND_UP(SIDTAB_MAX_BITS - size_to_shift(SIDTAB_LEAF_ENTRIES), \
+		     SIDTAB_INNER_SHIFT)
+
+struct sidtab_node_leaf {
+	struct sidtab_entry entries[SIDTAB_LEAF_ENTRIES];
+};
+
+struct sidtab_node_inner {
+	union sidtab_entry_inner entries[SIDTAB_INNER_ENTRIES];
+};
+
+struct sidtab_isid_entry {
+	int set;
+	struct sidtab_entry entry;
+};
+
+struct sidtab_convert_params {
+	struct convert_context_args *args;
+	struct sidtab *target;
+};
+
+#define SIDTAB_HASH_BITS    CONFIG_SECURITY_SELINUX_SIDTAB_HASH_BITS
+#define SIDTAB_HASH_BUCKETS (1 << SIDTAB_HASH_BITS)
+
+struct sidtab {
+	/*
+	 * lock-free read access only for as many items as a prior read of
+	 * 'count'
+	 */
+	union sidtab_entry_inner roots[SIDTAB_MAX_LEVEL + 1];
+	/*
+	 * access atomically via {READ|WRITE}_ONCE(); only increment under
+	 * spinlock
+	 */
+	u32 count;
+	/* access only under spinlock */
+	struct sidtab_convert_params *convert;
+	bool frozen;
+	spinlock_t lock;
+
+#if CONFIG_SECURITY_SELINUX_SID2STR_CACHE_SIZE > 0
+	/* SID -> context string cache */
+	u32 cache_free_slots;
+	struct list_head cache_lru_list;
+	spinlock_t cache_lock;
+#endif
+
+	/* index == SID - 1 (no entry for SECSID_NULL) */
+	struct sidtab_isid_entry isids[SECINITSID_NUM];
+
+	/* Hash table for fast reverse context-to-sid lookups. */
+	DECLARE_HASHTABLE(context_to_sid, SIDTAB_HASH_BITS);
+};
+
+int sidtab_init(struct sidtab *s);
+int sidtab_set_initial(struct sidtab *s, u32 sid, struct context *context);
+struct sidtab_entry *sidtab_search_entry(struct sidtab *s, u32 sid);
+struct sidtab_entry *sidtab_search_entry_force(struct sidtab *s, u32 sid);
+
+static inline struct context *sidtab_search(struct sidtab *s, u32 sid)
+{
+	struct sidtab_entry *entry = sidtab_search_entry(s, sid);
+
+	return entry ? &entry->context : NULL;
+}
+
+static inline struct context *sidtab_search_force(struct sidtab *s, u32 sid)
+{
+	struct sidtab_entry *entry = sidtab_search_entry_force(s, sid);
+
+	return entry ? &entry->context : NULL;
+}
+
+int sidtab_convert(struct sidtab *s, struct sidtab_convert_params *params);
+
+void sidtab_cancel_convert(struct sidtab *s);
+
+void sidtab_freeze_begin(struct sidtab *s, unsigned long *flags)
+	__acquires(&s->lock);
+void sidtab_freeze_end(struct sidtab *s, unsigned long *flags)
+	__releases(&s->lock);
+
+int sidtab_context_to_sid(struct sidtab *s, struct context *context, u32 *sid);
+
+void sidtab_destroy(struct sidtab *s);
+
+int sidtab_hash_stats(struct sidtab *sidtab, char *page);
+
+#if CONFIG_SECURITY_SELINUX_SID2STR_CACHE_SIZE > 0
+void sidtab_sid2str_put(struct sidtab *s, struct sidtab_entry *entry,
+			const char *str, u32 str_len);
+int sidtab_sid2str_get(struct sidtab *s, struct sidtab_entry *entry, char **out,
+		       u32 *out_len);
+#else
+static inline void sidtab_sid2str_put(struct sidtab *s,
+				      struct sidtab_entry *entry,
+				      const char *str, u32 str_len)
+{
+}
+static inline int sidtab_sid2str_get(struct sidtab *s,
+				     struct sidtab_entry *entry, char **out,
+				     u32 *out_len)
+{
+	return -ENOENT;
+}
+#endif /* CONFIG_SECURITY_SELINUX_SID2STR_CACHE_SIZE > 0 */
+
+#endif /* _SS_SIDTAB_H_ */

linux-7.2.3/security/selinux/ss/symtab.c

@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Implementation of the symbol table type.
+ *
+ * Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include "symtab.h"
+
+static unsigned int symhash(const void *key)
+{
+	/*
+	 * djb2a
+	 * Public domain from cdb v0.75
+	 */
+	unsigned int hash = 5381;
+	unsigned char c;
+
+	while ((c = *(const unsigned char *)key++))
+		hash = ((hash << 5) + hash) ^ c;
+
+	return hash;
+}
+
+static int symcmp(const void *key1, const void *key2)
+{
+	const char *keyp1, *keyp2;
+
+	keyp1 = key1;
+	keyp2 = key2;
+	return strcmp(keyp1, keyp2);
+}
+
+static const struct hashtab_key_params symtab_key_params = {
+	.hash = symhash,
+	.cmp = symcmp,
+};
+
+int symtab_init(struct symtab *s, u32 size)
+{
+	s->nprim = 0;
+	return hashtab_init(&s->table, size);
+}
+
+int symtab_insert(struct symtab *s, char *name, void *datum)
+{
+	return hashtab_insert(&s->table, name, datum, symtab_key_params);
+}
+
+void *symtab_search(const struct symtab *s, const char *name)
+{
+	return hashtab_search(&s->table, name, symtab_key_params);
+}

linux-7.2.3/security/selinux/ss/symtab.h

@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * A symbol table (symtab) maintains associations between symbol
+ * strings and datum values.  The type of the datum values
+ * is arbitrary.  The symbol table type is implemented
+ * using the hash table type (hashtab).
+ *
+ * Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
+ */
+
+#ifndef _SS_SYMTAB_H_
+#define _SS_SYMTAB_H_
+
+#include "hashtab.h"
+
+struct symtab {
+	struct hashtab table; /* hash table (keyed on a string) */
+	u32 nprim; /* number of primary names in table */
+};
+
+int symtab_init(struct symtab *s, u32 size);
+
+int symtab_insert(struct symtab *s, char *name, void *datum);
+void *symtab_search(const struct symtab *s, const char *name);
+
+#endif /* _SS_SYMTAB_H_ */