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Diffstat (limited to 'security/selinux/ss/avtab.c')
-rw-r--r--security/selinux/ss/avtab.c399
1 files changed, 399 insertions, 0 deletions
diff --git a/security/selinux/ss/avtab.c b/security/selinux/ss/avtab.c
new file mode 100644
index 00000000000..f238c034c44
--- /dev/null
+++ b/security/selinux/ss/avtab.c
@@ -0,0 +1,399 @@
+/*
+ * Implementation of the access vector table type.
+ *
+ * Author : Stephen Smalley, <sds@epoch.ncsc.mil>
+ */
+
+/* Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
+ *
+ * Added conditional policy language extensions
+ *
+ * Copyright (C) 2003 Tresys Technology, LLC
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2.
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/errno.h>
+
+#include "avtab.h"
+#include "policydb.h"
+
+#define AVTAB_HASH(keyp) \
+((keyp->target_class + \
+ (keyp->target_type << 2) + \
+ (keyp->source_type << 9)) & \
+ AVTAB_HASH_MASK)
+
+static kmem_cache_t *avtab_node_cachep;
+
+static struct avtab_node*
+avtab_insert_node(struct avtab *h, int hvalue,
+ struct avtab_node * prev, struct avtab_node * cur,
+ struct avtab_key *key, struct avtab_datum *datum)
+{
+ struct avtab_node * newnode;
+ newnode = kmem_cache_alloc(avtab_node_cachep, SLAB_KERNEL);
+ if (newnode == NULL)
+ return NULL;
+ memset(newnode, 0, sizeof(struct avtab_node));
+ newnode->key = *key;
+ newnode->datum = *datum;
+ if (prev) {
+ newnode->next = prev->next;
+ prev->next = newnode;
+ } else {
+ newnode->next = h->htable[hvalue];
+ h->htable[hvalue] = newnode;
+ }
+
+ h->nel++;
+ return newnode;
+}
+
+static int avtab_insert(struct avtab *h, struct avtab_key *key, struct avtab_datum *datum)
+{
+ int hvalue;
+ struct avtab_node *prev, *cur, *newnode;
+
+ if (!h)
+ return -EINVAL;
+
+ hvalue = AVTAB_HASH(key);
+ for (prev = NULL, cur = h->htable[hvalue];
+ cur;
+ prev = cur, cur = cur->next) {
+ if (key->source_type == cur->key.source_type &&
+ key->target_type == cur->key.target_type &&
+ key->target_class == cur->key.target_class &&
+ (datum->specified & cur->datum.specified))
+ return -EEXIST;
+ if (key->source_type < cur->key.source_type)
+ break;
+ if (key->source_type == cur->key.source_type &&
+ key->target_type < cur->key.target_type)
+ break;
+ if (key->source_type == cur->key.source_type &&
+ key->target_type == cur->key.target_type &&
+ key->target_class < cur->key.target_class)
+ break;
+ }
+
+ newnode = avtab_insert_node(h, hvalue, prev, cur, 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, struct avtab_key * key, struct avtab_datum * datum)
+{
+ int hvalue;
+ struct avtab_node *prev, *cur, *newnode;
+
+ if (!h)
+ return NULL;
+ hvalue = AVTAB_HASH(key);
+ for (prev = NULL, cur = h->htable[hvalue];
+ cur;
+ prev = cur, cur = cur->next) {
+ if (key->source_type == cur->key.source_type &&
+ key->target_type == cur->key.target_type &&
+ key->target_class == cur->key.target_class &&
+ (datum->specified & cur->datum.specified))
+ break;
+ if (key->source_type < cur->key.source_type)
+ break;
+ if (key->source_type == cur->key.source_type &&
+ key->target_type < cur->key.target_type)
+ break;
+ if (key->source_type == cur->key.source_type &&
+ key->target_type == cur->key.target_type &&
+ key->target_class < cur->key.target_class)
+ break;
+ }
+ newnode = avtab_insert_node(h, hvalue, prev, cur, key, datum);
+
+ return newnode;
+}
+
+struct avtab_datum *avtab_search(struct avtab *h, struct avtab_key *key, int specified)
+{
+ int hvalue;
+ struct avtab_node *cur;
+
+ if (!h)
+ return NULL;
+
+ hvalue = AVTAB_HASH(key);
+ for (cur = h->htable[hvalue]; cur; cur = cur->next) {
+ if (key->source_type == cur->key.source_type &&
+ key->target_type == cur->key.target_type &&
+ key->target_class == cur->key.target_class &&
+ (specified & cur->datum.specified))
+ return &cur->datum;
+
+ if (key->source_type < cur->key.source_type)
+ break;
+ if (key->source_type == cur->key.source_type &&
+ key->target_type < cur->key.target_type)
+ break;
+ if (key->source_type == cur->key.source_type &&
+ key->target_type == cur->key.target_type &&
+ key->target_class < cur->key.target_class)
+ break;
+ }
+
+ return NULL;
+}
+
+/* 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, struct avtab_key *key, int specified)
+{
+ int hvalue;
+ struct avtab_node *cur;
+
+ if (!h)
+ return NULL;
+
+ hvalue = AVTAB_HASH(key);
+ for (cur = h->htable[hvalue]; cur; cur = cur->next) {
+ if (key->source_type == cur->key.source_type &&
+ key->target_type == cur->key.target_type &&
+ key->target_class == cur->key.target_class &&
+ (specified & cur->datum.specified))
+ return cur;
+
+ if (key->source_type < cur->key.source_type)
+ break;
+ if (key->source_type == cur->key.source_type &&
+ key->target_type < cur->key.target_type)
+ break;
+ if (key->source_type == cur->key.source_type &&
+ key->target_type == cur->key.target_type &&
+ key->target_class < cur->key.target_class)
+ break;
+ }
+ return NULL;
+}
+
+struct avtab_node*
+avtab_search_node_next(struct avtab_node *node, int specified)
+{
+ struct avtab_node *cur;
+
+ if (!node)
+ return NULL;
+
+ for (cur = node->next; cur; cur = cur->next) {
+ if (node->key.source_type == cur->key.source_type &&
+ node->key.target_type == cur->key.target_type &&
+ node->key.target_class == cur->key.target_class &&
+ (specified & cur->datum.specified))
+ return cur;
+
+ if (node->key.source_type < cur->key.source_type)
+ break;
+ if (node->key.source_type == cur->key.source_type &&
+ node->key.target_type < cur->key.target_type)
+ break;
+ if (node->key.source_type == cur->key.source_type &&
+ node->key.target_type == cur->key.target_type &&
+ node->key.target_class < cur->key.target_class)
+ break;
+ }
+ return NULL;
+}
+
+void avtab_destroy(struct avtab *h)
+{
+ int i;
+ struct avtab_node *cur, *temp;
+
+ if (!h || !h->htable)
+ return;
+
+ for (i = 0; i < AVTAB_SIZE; i++) {
+ cur = h->htable[i];
+ while (cur != NULL) {
+ temp = cur;
+ cur = cur->next;
+ kmem_cache_free(avtab_node_cachep, temp);
+ }
+ h->htable[i] = NULL;
+ }
+ vfree(h->htable);
+ h->htable = NULL;
+}
+
+
+int avtab_init(struct avtab *h)
+{
+ int i;
+
+ h->htable = vmalloc(sizeof(*(h->htable)) * AVTAB_SIZE);
+ if (!h->htable)
+ return -ENOMEM;
+ for (i = 0; i < AVTAB_SIZE; i++)
+ h->htable[i] = NULL;
+ h->nel = 0;
+ return 0;
+}
+
+void avtab_hash_eval(struct avtab *h, char *tag)
+{
+ int i, chain_len, slots_used, max_chain_len;
+ struct avtab_node *cur;
+
+ slots_used = 0;
+ max_chain_len = 0;
+ for (i = 0; i < AVTAB_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;
+ }
+ }
+
+ printk(KERN_INFO "%s: %d entries and %d/%d buckets used, longest "
+ "chain length %d\n", tag, h->nel, slots_used, AVTAB_SIZE,
+ max_chain_len);
+}
+
+int avtab_read_item(void *fp, struct avtab_datum *avdatum, struct avtab_key *avkey)
+{
+ u32 buf[7];
+ u32 items, items2;
+ int rc;
+
+ memset(avkey, 0, sizeof(struct avtab_key));
+ memset(avdatum, 0, sizeof(struct avtab_datum));
+
+ rc = next_entry(buf, fp, sizeof(u32));
+ if (rc < 0) {
+ printk(KERN_ERR "security: avtab: truncated entry\n");
+ goto bad;
+ }
+ items2 = le32_to_cpu(buf[0]);
+ if (items2 > ARRAY_SIZE(buf)) {
+ printk(KERN_ERR "security: avtab: entry overflow\n");
+ goto bad;
+ }
+ rc = next_entry(buf, fp, sizeof(u32)*items2);
+ if (rc < 0) {
+ printk(KERN_ERR "security: avtab: truncated entry\n");
+ goto bad;
+ }
+ items = 0;
+ avkey->source_type = le32_to_cpu(buf[items++]);
+ avkey->target_type = le32_to_cpu(buf[items++]);
+ avkey->target_class = le32_to_cpu(buf[items++]);
+ avdatum->specified = le32_to_cpu(buf[items++]);
+ if (!(avdatum->specified & (AVTAB_AV | AVTAB_TYPE))) {
+ printk(KERN_ERR "security: avtab: null entry\n");
+ goto bad;
+ }
+ if ((avdatum->specified & AVTAB_AV) &&
+ (avdatum->specified & AVTAB_TYPE)) {
+ printk(KERN_ERR "security: avtab: entry has both access vectors and types\n");
+ goto bad;
+ }
+ if (avdatum->specified & AVTAB_AV) {
+ if (avdatum->specified & AVTAB_ALLOWED)
+ avtab_allowed(avdatum) = le32_to_cpu(buf[items++]);
+ if (avdatum->specified & AVTAB_AUDITDENY)
+ avtab_auditdeny(avdatum) = le32_to_cpu(buf[items++]);
+ if (avdatum->specified & AVTAB_AUDITALLOW)
+ avtab_auditallow(avdatum) = le32_to_cpu(buf[items++]);
+ } else {
+ if (avdatum->specified & AVTAB_TRANSITION)
+ avtab_transition(avdatum) = le32_to_cpu(buf[items++]);
+ if (avdatum->specified & AVTAB_CHANGE)
+ avtab_change(avdatum) = le32_to_cpu(buf[items++]);
+ if (avdatum->specified & AVTAB_MEMBER)
+ avtab_member(avdatum) = le32_to_cpu(buf[items++]);
+ }
+ if (items != items2) {
+ printk(KERN_ERR "security: avtab: entry only had %d items, expected %d\n",
+ items2, items);
+ goto bad;
+ }
+
+ return 0;
+bad:
+ return -1;
+}
+
+int avtab_read(struct avtab *a, void *fp, u32 config)
+{
+ int rc;
+ struct avtab_key avkey;
+ struct avtab_datum avdatum;
+ u32 buf[1];
+ u32 nel, i;
+
+
+ rc = next_entry(buf, fp, sizeof(u32));
+ if (rc < 0) {
+ printk(KERN_ERR "security: avtab: truncated table\n");
+ goto bad;
+ }
+ nel = le32_to_cpu(buf[0]);
+ if (!nel) {
+ printk(KERN_ERR "security: avtab: table is empty\n");
+ rc = -EINVAL;
+ goto bad;
+ }
+ for (i = 0; i < nel; i++) {
+ if (avtab_read_item(fp, &avdatum, &avkey)) {
+ rc = -EINVAL;
+ goto bad;
+ }
+ rc = avtab_insert(a, &avkey, &avdatum);
+ if (rc) {
+ if (rc == -ENOMEM)
+ printk(KERN_ERR "security: avtab: out of memory\n");
+ if (rc == -EEXIST)
+ printk(KERN_ERR "security: avtab: duplicate entry\n");
+ goto bad;
+ }
+ }
+
+ rc = 0;
+out:
+ return rc;
+
+bad:
+ avtab_destroy(a);
+ goto out;
+}
+
+void avtab_cache_init(void)
+{
+ avtab_node_cachep = kmem_cache_create("avtab_node",
+ sizeof(struct avtab_node),
+ 0, SLAB_PANIC, NULL, NULL);
+}
+
+void avtab_cache_destroy(void)
+{
+ kmem_cache_destroy (avtab_node_cachep);
+}
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-12-03 06:03:32 +0000