[PATCH] selinux: add hooks for key subsystem

Introduce SELinux hooks to support the access key retention subsystem
within the kernel.  Incorporate new flask headers from a modified version
of the SELinux reference policy, with support for the new security class
representing retained keys.  Extend the "key_alloc" security hook with a
task parameter representing the intended ownership context for the key
being allocated.  Attach security information to root's default keyrings
within the SELinux initialization routine.

Has passed David's testsuite.

Signed-off-by: Michael LeMay <mdlemay@epoch.ncsc.mil>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

5 files changed, 20 insertions, 16 deletions

diff --git a/security/keys/key.c b/security/keys/key.c
index 3fdc49c..14a15ab 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -247,8 +247,8 @@ static inline void key_alloc_serial(struct key *key)
  *   instantiate the key or discard it before returning
  */
 struct key *key_alloc(struct key_type *type, const char *desc,
-		      uid_t uid, gid_t gid, key_perm_t perm,
-		      int not_in_quota)
+		      uid_t uid, gid_t gid, struct task_struct *ctx,
+		      key_perm_t perm, int not_in_quota)
 {
 	struct key_user *user = NULL;
 	struct key *key;
@@ -318,7 +318,7 @@ struct key *key_alloc(struct key_type *type, const char *desc,
 #endif
 
 	/* let the security module know about the key */
-	ret = security_key_alloc(key);
+	ret = security_key_alloc(key, ctx);
 	if (ret < 0)
 		goto security_error;
 
@@ -822,7 +822,7 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
 
 	/* allocate a new key */
 	key = key_alloc(ktype, description, current->fsuid, current->fsgid,
-			perm, not_in_quota);
+			current, perm, not_in_quota);
 	if (IS_ERR(key)) {
 		key_ref = ERR_PTR(PTR_ERR(key));
 		goto error_3;
diff --git a/security/keys/keyring.c b/security/keys/keyring.c
index bffa924..1357207 100644
--- a/security/keys/keyring.c
+++ b/security/keys/keyring.c
@@ -240,13 +240,14 @@ static long keyring_read(const struct key *keyring,
  * allocate a keyring and link into the destination keyring
  */
 struct key *keyring_alloc(const char *description, uid_t uid, gid_t gid,
-			  int not_in_quota, struct key *dest)
+			  struct task_struct *ctx, int not_in_quota,
+			  struct key *dest)
 {
 	struct key *keyring;
 	int ret;
 
 	keyring = key_alloc(&key_type_keyring, description,
-			    uid, gid,
+			    uid, gid, ctx,
 			    (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL,
 			    not_in_quota);
 
diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
index 217a0be..a50a913 100644
--- a/security/keys/process_keys.c
+++ b/security/keys/process_keys.c
@@ -67,7 +67,8 @@ struct key root_session_keyring = {
 /*
  * allocate the keyrings to be associated with a UID
  */
-int alloc_uid_keyring(struct user_struct *user)
+int alloc_uid_keyring(struct user_struct *user,
+		      struct task_struct *ctx)
 {
 	struct key *uid_keyring, *session_keyring;
 	char buf[20];
@@ -76,7 +77,7 @@ int alloc_uid_keyring(struct user_struct *user)
 	/* concoct a default session keyring */
 	sprintf(buf, "_uid_ses.%u", user->uid);
 
-	session_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, 0, NULL);
+	session_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, ctx, 0, NULL);
 	if (IS_ERR(session_keyring)) {
 		ret = PTR_ERR(session_keyring);
 		goto error;
@@ -86,7 +87,7 @@ int alloc_uid_keyring(struct user_struct *user)
 	 * keyring */
 	sprintf(buf, "_uid.%u", user->uid);
 
-	uid_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, 0,
+	uid_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, ctx, 0,
 				    session_keyring);
 	if (IS_ERR(uid_keyring)) {
 		key_put(session_keyring);
@@ -143,7 +144,7 @@ int install_thread_keyring(struct task_struct *tsk)
 
 	sprintf(buf, "_tid.%u", tsk->pid);
 
-	keyring = keyring_alloc(buf, tsk->uid, tsk->gid, 1, NULL);
+	keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk, 1, NULL);
 	if (IS_ERR(keyring)) {
 		ret = PTR_ERR(keyring);
 		goto error;
@@ -177,7 +178,7 @@ int install_process_keyring(struct task_struct *tsk)
 	if (!tsk->signal->process_keyring) {
 		sprintf(buf, "_pid.%u", tsk->tgid);
 
-		keyring = keyring_alloc(buf, tsk->uid, tsk->gid, 1, NULL);
+		keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk, 1, NULL);
 		if (IS_ERR(keyring)) {
 			ret = PTR_ERR(keyring);
 			goto error;
@@ -217,7 +218,7 @@ static int install_session_keyring(struct task_struct *tsk,
 	if (!keyring) {
 		sprintf(buf, "_ses.%u", tsk->tgid);
 
-		keyring = keyring_alloc(buf, tsk->uid, tsk->gid, 1, NULL);
+		keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk, 1, NULL);
 		if (IS_ERR(keyring))
 			return PTR_ERR(keyring);
 	}
@@ -717,7 +718,7 @@ long join_session_keyring(const char *name)
 	keyring = find_keyring_by_name(name, 0);
 	if (PTR_ERR(keyring) == -ENOKEY) {
 		/* not found - try and create a new one */
-		keyring = keyring_alloc(name, tsk->uid, tsk->gid, 0, NULL);
+		keyring = keyring_alloc(name, tsk->uid, tsk->gid, tsk, 0, NULL);
 		if (IS_ERR(keyring)) {
 			ret = PTR_ERR(keyring);
 			goto error2;
diff --git a/security/keys/request_key.c b/security/keys/request_key.c
index f030a0c..eab66a0 100644
--- a/security/keys/request_key.c
+++ b/security/keys/request_key.c
@@ -48,7 +48,8 @@ static int call_sbin_request_key(struct key *key,
 	/* allocate a new session keyring */
 	sprintf(desc, "_req.%u", key->serial);
 
-	keyring = keyring_alloc(desc, current->fsuid, current->fsgid, 1, NULL);
+	keyring = keyring_alloc(desc, current->fsuid, current->fsgid,
+				current, 1, NULL);
 	if (IS_ERR(keyring)) {
 		ret = PTR_ERR(keyring);
 		goto error_alloc;
@@ -137,7 +138,8 @@ static struct key *__request_key_construction(struct key_type *type,
 
 	/* create a key and add it to the queue */
 	key = key_alloc(type, description,
-			current->fsuid, current->fsgid, KEY_POS_ALL, 0);
+			current->fsuid, current->fsgid,
+			current, KEY_POS_ALL, 0);
 	if (IS_ERR(key))
 		goto alloc_failed;
 
diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c
index cce6ba6..0ecc2e8 100644
--- a/security/keys/request_key_auth.c
+++ b/security/keys/request_key_auth.c
@@ -148,7 +148,7 @@ struct key *request_key_auth_new(struct key *target, const char *callout_info)
 	sprintf(desc, "%x", target->serial);
 
 	authkey = key_alloc(&key_type_request_key_auth, desc,
-			    current->fsuid, current->fsgid,
+			    current->fsuid, current->fsgid, current,
 			    KEY_POS_VIEW | KEY_POS_READ | KEY_POS_SEARCH |
 			    KEY_USR_VIEW, 1);
 	if (IS_ERR(authkey)) {