*
* Added support for NetLabel
*
+ * Updated: Chad Sellers <csellers@tresys.com>
+ *
+ * Added validation of kernel classes and permissions
+ *
* Copyright (C) 2006 Hewlett-Packard Development Company, L.P.
* Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
- * Copyright (C) 2003 - 2004 Tresys Technology, LLC
+ * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC
* Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
* 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
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/spinlock.h>
+#include <linux/rcupdate.h>
#include <linux/errno.h>
#include <linux/in.h>
#include <linux/sched.h>
extern void selnl_notify_policyload(u32 seqno);
unsigned int policydb_loaded_version;
+/*
+ * This is declared in avc.c
+ */
+extern const struct selinux_class_perm selinux_class_perm;
+
static DEFINE_RWLOCK(policy_rwlock);
#define POLICY_RDLOCK read_lock(&policy_rwlock)
#define POLICY_WRLOCK write_lock_irq(&policy_rwlock)
}
/*
- * Verify that each permission that is defined under the
- * existing policy is still defined with the same value
- * in the new policy.
+ * Verify that each kernel class that is defined in the
+ * policy is correct
*/
-static int validate_perm(void *key, void *datum, void *p)
+static int validate_classes(struct policydb *p)
{
- struct hashtab *h;
- struct perm_datum *perdatum, *perdatum2;
- int rc = 0;
-
-
- h = p;
- perdatum = datum;
-
- perdatum2 = hashtab_search(h, key);
- if (!perdatum2) {
- printk(KERN_ERR "security: permission %s disappeared",
- (char *)key);
- rc = -ENOENT;
- goto out;
- }
- if (perdatum->value != perdatum2->value) {
- printk(KERN_ERR "security: the value of permission %s changed",
- (char *)key);
- rc = -EINVAL;
- }
-out:
- return rc;
-}
-
-/*
- * Verify that each class that is defined under the
- * existing policy is still defined with the same
- * attributes in the new policy.
- */
-static int validate_class(void *key, void *datum, void *p)
-{
- struct policydb *newp;
- struct class_datum *cladatum, *cladatum2;
- int rc;
-
- newp = p;
- cladatum = datum;
-
- cladatum2 = hashtab_search(newp->p_classes.table, key);
- if (!cladatum2) {
- printk(KERN_ERR "security: class %s disappeared\n",
- (char *)key);
- rc = -ENOENT;
- goto out;
- }
- if (cladatum->value != cladatum2->value) {
- printk(KERN_ERR "security: the value of class %s changed\n",
- (char *)key);
- rc = -EINVAL;
- goto out;
+ int i, j;
+ struct class_datum *cladatum;
+ struct perm_datum *perdatum;
+ u32 nprim, tmp, common_pts_len, perm_val, pol_val;
+ u16 class_val;
+ const struct selinux_class_perm *kdefs = &selinux_class_perm;
+ const char *def_class, *def_perm, *pol_class;
+ struct symtab *perms;
+
+ for (i = 1; i < kdefs->cts_len; i++) {
+ def_class = kdefs->class_to_string[i];
+ if (i > p->p_classes.nprim) {
+ printk(KERN_INFO
+ "security: class %s not defined in policy\n",
+ def_class);
+ continue;
+ }
+ pol_class = p->p_class_val_to_name[i-1];
+ if (strcmp(pol_class, def_class)) {
+ printk(KERN_ERR
+ "security: class %d is incorrect, found %s but should be %s\n",
+ i, pol_class, def_class);
+ return -EINVAL;
+ }
}
- if ((cladatum->comdatum && !cladatum2->comdatum) ||
- (!cladatum->comdatum && cladatum2->comdatum)) {
- printk(KERN_ERR "security: the inherits clause for the access "
- "vector definition for class %s changed\n", (char *)key);
- rc = -EINVAL;
- goto out;
+ for (i = 0; i < kdefs->av_pts_len; i++) {
+ class_val = kdefs->av_perm_to_string[i].tclass;
+ perm_val = kdefs->av_perm_to_string[i].value;
+ def_perm = kdefs->av_perm_to_string[i].name;
+ if (class_val > p->p_classes.nprim)
+ continue;
+ pol_class = p->p_class_val_to_name[class_val-1];
+ cladatum = hashtab_search(p->p_classes.table, pol_class);
+ BUG_ON(!cladatum);
+ perms = &cladatum->permissions;
+ nprim = 1 << (perms->nprim - 1);
+ if (perm_val > nprim) {
+ printk(KERN_INFO
+ "security: permission %s in class %s not defined in policy\n",
+ def_perm, pol_class);
+ continue;
+ }
+ perdatum = hashtab_search(perms->table, def_perm);
+ if (perdatum == NULL) {
+ printk(KERN_ERR
+ "security: permission %s in class %s not found in policy\n",
+ def_perm, pol_class);
+ return -EINVAL;
+ }
+ pol_val = 1 << (perdatum->value - 1);
+ if (pol_val != perm_val) {
+ printk(KERN_ERR
+ "security: permission %s in class %s has incorrect value\n",
+ def_perm, pol_class);
+ return -EINVAL;
+ }
}
- if (cladatum->comdatum) {
- rc = hashtab_map(cladatum->comdatum->permissions.table, validate_perm,
- cladatum2->comdatum->permissions.table);
- if (rc) {
- printk(" in the access vector definition for class "
- "%s\n", (char *)key);
- goto out;
+ for (i = 0; i < kdefs->av_inherit_len; i++) {
+ class_val = kdefs->av_inherit[i].tclass;
+ if (class_val > p->p_classes.nprim)
+ continue;
+ pol_class = p->p_class_val_to_name[class_val-1];
+ cladatum = hashtab_search(p->p_classes.table, pol_class);
+ BUG_ON(!cladatum);
+ if (!cladatum->comdatum) {
+ printk(KERN_ERR
+ "security: class %s should have an inherits clause but does not\n",
+ pol_class);
+ return -EINVAL;
+ }
+ tmp = kdefs->av_inherit[i].common_base;
+ common_pts_len = 0;
+ while (!(tmp & 0x01)) {
+ common_pts_len++;
+ tmp >>= 1;
+ }
+ perms = &cladatum->comdatum->permissions;
+ for (j = 0; j < common_pts_len; j++) {
+ def_perm = kdefs->av_inherit[i].common_pts[j];
+ if (j >= perms->nprim) {
+ printk(KERN_INFO
+ "security: permission %s in class %s not defined in policy\n",
+ def_perm, pol_class);
+ continue;
+ }
+ perdatum = hashtab_search(perms->table, def_perm);
+ if (perdatum == NULL) {
+ printk(KERN_ERR
+ "security: permission %s in class %s not found in policy\n",
+ def_perm, pol_class);
+ return -EINVAL;
+ }
+ if (perdatum->value != j + 1) {
+ printk(KERN_ERR
+ "security: permission %s in class %s has incorrect value\n",
+ def_perm, pol_class);
+ return -EINVAL;
+ }
}
}
- rc = hashtab_map(cladatum->permissions.table, validate_perm,
- cladatum2->permissions.table);
- if (rc)
- printk(" in access vector definition for class %s\n",
- (char *)key);
-out:
- return rc;
+ return 0;
}
/* Clone the SID into the new SID table. */
avtab_cache_destroy();
return -EINVAL;
}
+ /* Verify that the kernel defined classes are correct. */
+ if (validate_classes(&policydb)) {
+ printk(KERN_ERR
+ "security: the definition of a class is incorrect\n");
+ LOAD_UNLOCK;
+ sidtab_destroy(&sidtab);
+ policydb_destroy(&policydb);
+ avtab_cache_destroy();
+ return -EINVAL;
+ }
policydb_loaded_version = policydb.policyvers;
ss_initialized = 1;
seqno = ++latest_granting;
sidtab_init(&newsidtab);
- /* Verify that the existing classes did not change. */
- if (hashtab_map(policydb.p_classes.table, validate_class, &newpolicydb)) {
- printk(KERN_ERR "security: the definition of an existing "
- "class changed\n");
+ /* Verify that the kernel defined classes are correct. */
+ if (validate_classes(&newpolicydb)) {
+ printk(KERN_ERR
+ "security: the definition of a class is incorrect\n");
rc = -EINVAL;
goto err;
}
cache = kzalloc(sizeof(*cache), GFP_ATOMIC);
if (cache == NULL)
goto netlbl_cache_add_return;
- secattr.cache->free = selinux_netlbl_cache_free;
- secattr.cache->data = (void *)cache;
cache->type = NETLBL_CACHE_T_MLS;
if (ebitmap_cpy(&cache->data.mls_label.level[0].cat,
cache->data.mls_label.level[0].sens = ctx->range.level[0].sens;
cache->data.mls_label.level[1].sens = ctx->range.level[0].sens;
+ secattr.cache->free = selinux_netlbl_cache_free;
+ secattr.cache->data = (void *)cache;
+ secattr.flags = NETLBL_SECATTR_CACHE;
+
netlbl_cache_add(skb, &secattr);
netlbl_cache_add_return:
POLICY_RDLOCK;
- if (secattr->cache) {
+ if (secattr->flags & NETLBL_SECATTR_CACHE) {
cache = NETLBL_CACHE(secattr->cache->data);
switch (cache->type) {
case NETLBL_CACHE_T_SID:
default:
goto netlbl_secattr_to_sid_return;
}
- } else if (secattr->mls_lvl_vld) {
+ } else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
ctx = sidtab_search(&sidtab, base_sid);
if (ctx == NULL)
goto netlbl_secattr_to_sid_return;
ctx_new.role = ctx->role;
ctx_new.type = ctx->type;
mls_import_lvl(&ctx_new, secattr->mls_lvl, secattr->mls_lvl);
- if (secattr->mls_cat) {
+ if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
if (mls_import_cat(&ctx_new,
secattr->mls_cat,
secattr->mls_cat_len,
netlbl_secattr_init(&secattr);
rc = netlbl_skbuff_getattr(skb, &secattr);
- if (rc == 0)
+ if (rc == 0 && secattr.flags != NETLBL_SECATTR_NONE)
rc = selinux_netlbl_secattr_to_sid(skb,
&secattr,
base_sid,
sid);
+ else
+ *sid = SECSID_NULL;
netlbl_secattr_destroy(&secattr);
return rc;
*
* Description:
* Attempt to label a socket using the NetLabel mechanism using the given
- * SID. Returns zero values on success, negative values on failure.
+ * SID. Returns zero values on success, negative values on failure. The
+ * caller is responsibile for calling rcu_read_lock() before calling this
+ * this function and rcu_read_unlock() after this function returns.
*
*/
static int selinux_netlbl_socket_setsid(struct socket *sock, u32 sid)
secattr.domain = kstrdup(policydb.p_type_val_to_name[ctx->type - 1],
GFP_ATOMIC);
mls_export_lvl(ctx, &secattr.mls_lvl, NULL);
- secattr.mls_lvl_vld = 1;
rc = mls_export_cat(ctx,
&secattr.mls_cat,
&secattr.mls_cat_len,
if (rc != 0)
goto netlbl_socket_setsid_return;
+ secattr.flags |= NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL;
+ if (secattr.mls_cat)
+ secattr.flags |= NETLBL_SECATTR_MLS_CAT;
+
rc = netlbl_socket_setattr(sock, &secattr);
- if (rc == 0)
+ if (rc == 0) {
+ spin_lock(&sksec->nlbl_lock);
sksec->nlbl_state = NLBL_LABELED;
+ spin_unlock(&sksec->nlbl_lock);
+ }
netlbl_socket_setsid_return:
POLICY_RDUNLOCK;
return rc;
}
+/**
+ * selinux_netlbl_sk_security_reset - Reset the NetLabel fields
+ * @ssec: the sk_security_struct
+ * @family: the socket family
+ *
+ * Description:
+ * Called when the NetLabel state of a sk_security_struct needs to be reset.
+ * The caller is responsibile for all the NetLabel sk_security_struct locking.
+ *
+ */
+void selinux_netlbl_sk_security_reset(struct sk_security_struct *ssec,
+ int family)
+{
+ if (family == PF_INET)
+ ssec->nlbl_state = NLBL_REQUIRE;
+ else
+ ssec->nlbl_state = NLBL_UNSET;
+}
+
/**
* selinux_netlbl_sk_security_init - Setup the NetLabel fields
* @ssec: the sk_security_struct
void selinux_netlbl_sk_security_init(struct sk_security_struct *ssec,
int family)
{
- if (family == PF_INET)
- ssec->nlbl_state = NLBL_REQUIRE;
- else
- ssec->nlbl_state = NLBL_UNSET;
+ /* No locking needed, we are the only one who has access to ssec */
+ selinux_netlbl_sk_security_reset(ssec, family);
+ spin_lock_init(&ssec->nlbl_lock);
}
/**
- * selinux_netlbl_sk_clone_security - Copy the NetLabel fields
+ * selinux_netlbl_sk_security_clone - Copy the NetLabel fields
* @ssec: the original sk_security_struct
* @newssec: the cloned sk_security_struct
*
* @newssec.
*
*/
-void selinux_netlbl_sk_clone_security(struct sk_security_struct *ssec,
+void selinux_netlbl_sk_security_clone(struct sk_security_struct *ssec,
struct sk_security_struct *newssec)
{
+ /* We don't need to take newssec->nlbl_lock because we are the only
+ * thread with access to newssec, but we do need to take the RCU read
+ * lock as other threads could have access to ssec */
+ rcu_read_lock();
+ selinux_netlbl_sk_security_reset(newssec, ssec->sk->sk_family);
newssec->sclass = ssec->sclass;
- if (ssec->nlbl_state != NLBL_UNSET)
- newssec->nlbl_state = NLBL_REQUIRE;
- else
- newssec->nlbl_state = NLBL_UNSET;
+ rcu_read_unlock();
}
/**
* selinux_netlbl_socket_post_create - Label a socket using NetLabel
* @sock: the socket to label
- * @sock_family: the socket family
- * @sid: the SID to use
*
* Description:
* Attempt to label a socket using the NetLabel mechanism using the given
* SID. Returns zero values on success, negative values on failure.
*
*/
-int selinux_netlbl_socket_post_create(struct socket *sock,
- int sock_family,
- u32 sid)
+int selinux_netlbl_socket_post_create(struct socket *sock)
{
+ int rc = 0;
struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
struct sk_security_struct *sksec = sock->sk->sk_security;
sksec->sclass = isec->sclass;
- if (sock_family != PF_INET)
- return 0;
+ rcu_read_lock();
+ if (sksec->nlbl_state == NLBL_REQUIRE)
+ rc = selinux_netlbl_socket_setsid(sock, sksec->sid);
+ rcu_read_unlock();
- sksec->nlbl_state = NLBL_REQUIRE;
- return selinux_netlbl_socket_setsid(sock, sid);
+ return rc;
}
/**
sksec->sclass = isec->sclass;
- if (sk->sk_family != PF_INET)
+ rcu_read_lock();
+
+ if (sksec->nlbl_state != NLBL_REQUIRE) {
+ rcu_read_unlock();
return;
+ }
netlbl_secattr_init(&secattr);
if (netlbl_sock_getattr(sk, &secattr) == 0 &&
+ secattr.flags != NETLBL_SECATTR_NONE &&
selinux_netlbl_secattr_to_sid(NULL,
&secattr,
SECINITSID_UNLABELED,
sksec->peer_sid = nlbl_peer_sid;
netlbl_secattr_destroy(&secattr);
- sksec->nlbl_state = NLBL_REQUIRE;
-
/* Try to set the NetLabel on the socket to save time later, if we fail
* here we will pick up the pieces in later calls to
* selinux_netlbl_inode_permission(). */
selinux_netlbl_socket_setsid(sock, sksec->sid);
+
+ rcu_read_unlock();
}
/**
int selinux_netlbl_inode_permission(struct inode *inode, int mask)
{
int rc;
- struct inode_security_struct *isec;
struct sk_security_struct *sksec;
struct socket *sock;
- if (!S_ISSOCK(inode->i_mode))
+ if (!S_ISSOCK(inode->i_mode) ||
+ ((mask & (MAY_WRITE | MAY_APPEND)) == 0))
return 0;
-
sock = SOCKET_I(inode);
- isec = inode->i_security;
sksec = sock->sk->sk_security;
- mutex_lock(&isec->lock);
- if (unlikely(sksec->nlbl_state == NLBL_REQUIRE &&
- (mask & (MAY_WRITE | MAY_APPEND)))) {
- lock_sock(sock->sk);
- rc = selinux_netlbl_socket_setsid(sock, sksec->sid);
- release_sock(sock->sk);
- } else
- rc = 0;
- mutex_unlock(&isec->lock);
+
+ rcu_read_lock();
+ if (sksec->nlbl_state != NLBL_REQUIRE) {
+ rcu_read_unlock();
+ return 0;
+ }
+ lock_sock(sock->sk);
+ rc = selinux_netlbl_socket_setsid(sock, sksec->sid);
+ release_sock(sock->sk);
+ rcu_read_unlock();
return rc;
}
int optname)
{
int rc = 0;
- struct inode *inode = SOCK_INODE(sock);
struct sk_security_struct *sksec = sock->sk->sk_security;
- struct inode_security_struct *isec = inode->i_security;
struct netlbl_lsm_secattr secattr;
- mutex_lock(&isec->lock);
+ rcu_read_lock();
if (level == IPPROTO_IP && optname == IP_OPTIONS &&
sksec->nlbl_state == NLBL_LABELED) {
netlbl_secattr_init(&secattr);
rc = netlbl_socket_getattr(sock, &secattr);
- if (rc == 0 && (secattr.cache || secattr.mls_lvl_vld))
+ if (rc == 0 && secattr.flags != NETLBL_SECATTR_NONE)
rc = -EACCES;
netlbl_secattr_destroy(&secattr);
}
- mutex_unlock(&isec->lock);
+ rcu_read_unlock();
return rc;
}
Code Review / linux-3.10.git / blobdiff