X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=security%2Fkeys%2Fkeyctl.c;h=3d2ebae029c1775b49722314b2def71bc4aabe9d;hb=0a3a98f6dd4e8f4d928a09302c0d1c56f2192ac3;hp=a6516a64b297898923ca760e2e3b779880021c30;hpb=1d492eb41371d9a5145651e8eb64bea1042a4057;p=powerpc.git

diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
index a6516a64b2..3d2ebae029 100644
--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -34,7 +34,7 @@ asmlinkage long sys_add_key(const char __user *_type,
 			    size_t plen,
 			    key_serial_t ringid)
 {
-	struct key *keyring, *key;
+	key_ref_t keyring_ref, key_ref;
 	char type[32], *description;
 	void *payload;
 	long dlen, ret;
@@ -86,25 +86,25 @@ asmlinkage long sys_add_key(const char __user *_type,
 	}
 
 	/* find the target keyring (which must be writable) */
-	keyring = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE);
-	if (IS_ERR(keyring)) {
-		ret = PTR_ERR(keyring);
+	keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE);
+	if (IS_ERR(keyring_ref)) {
+		ret = PTR_ERR(keyring_ref);
 		goto error3;
 	}
 
 	/* create or update the requested key and add it to the target
 	 * keyring */
-	key = key_create_or_update(keyring, type, description,
-				   payload, plen, 0);
-	if (!IS_ERR(key)) {
-		ret = key->serial;
-		key_put(key);
+	key_ref = key_create_or_update(keyring_ref, type, description,
+				       payload, plen, 0);
+	if (!IS_ERR(key_ref)) {
+		ret = key_ref_to_ptr(key_ref)->serial;
+		key_ref_put(key_ref);
 	}
 	else {
-		ret = PTR_ERR(key);
+		ret = PTR_ERR(key_ref);
 	}
 
-	key_put(keyring);
+	key_ref_put(keyring_ref);
  error3:
 	kfree(payload);
  error2:
@@ -131,7 +131,8 @@ asmlinkage long sys_request_key(const char __user *_type,
 				key_serial_t destringid)
 {
 	struct key_type *ktype;
-	struct key *key, *dest;
+	struct key *key;
+	key_ref_t dest_ref;
 	char type[32], *description, *callout_info;
 	long dlen, ret;
 
@@ -187,11 +188,11 @@ asmlinkage long sys_request_key(const char __user *_type,
 	}
 
 	/* get the destination keyring if specified */
-	dest = NULL;
+	dest_ref = NULL;
 	if (destringid) {
-		dest = lookup_user_key(NULL, destringid, 1, 0, KEY_WRITE);
-		if (IS_ERR(dest)) {
-			ret = PTR_ERR(dest);
+		dest_ref = lookup_user_key(NULL, destringid, 1, 0, KEY_WRITE);
+		if (IS_ERR(dest_ref)) {
+			ret = PTR_ERR(dest_ref);
 			goto error3;
 		}
 	}
@@ -204,7 +205,8 @@ asmlinkage long sys_request_key(const char __user *_type,
 	}
 
 	/* do the search */
-	key = request_key_and_link(ktype, description, callout_info, dest);
+	key = request_key_and_link(ktype, description, callout_info,
+				   key_ref_to_ptr(dest_ref));
 	if (IS_ERR(key)) {
 		ret = PTR_ERR(key);
 		goto error5;
@@ -216,7 +218,7 @@ asmlinkage long sys_request_key(const char __user *_type,
  error5:
 	key_type_put(ktype);
  error4:
-	key_put(dest);
+	key_ref_put(dest_ref);
  error3:
 	kfree(callout_info);
  error2:
@@ -234,17 +236,17 @@ asmlinkage long sys_request_key(const char __user *_type,
  */
 long keyctl_get_keyring_ID(key_serial_t id, int create)
 {
-	struct key *key;
+	key_ref_t key_ref;
 	long ret;
 
-	key = lookup_user_key(NULL, id, create, 0, KEY_SEARCH);
-	if (IS_ERR(key)) {
-		ret = PTR_ERR(key);
+	key_ref = lookup_user_key(NULL, id, create, 0, KEY_SEARCH);
+	if (IS_ERR(key_ref)) {
+		ret = PTR_ERR(key_ref);
 		goto error;
 	}
 
-	ret = key->serial;
-	key_put(key);
+	ret = key_ref_to_ptr(key_ref)->serial;
+	key_ref_put(key_ref);
  error:
 	return ret;
 
@@ -302,7 +304,7 @@ long keyctl_update_key(key_serial_t id,
 		       const void __user *_payload,
 		       size_t plen)
 {
-	struct key *key;
+	key_ref_t key_ref;
 	void *payload;
 	long ret;
 
@@ -324,16 +326,16 @@ long keyctl_update_key(key_serial_t id,
 	}
 
 	/* find the target key (which must be writable) */
-	key = lookup_user_key(NULL, id, 0, 0, KEY_WRITE);
-	if (IS_ERR(key)) {
-		ret = PTR_ERR(key);
+	key_ref = lookup_user_key(NULL, id, 0, 0, KEY_WRITE);
+	if (IS_ERR(key_ref)) {
+		ret = PTR_ERR(key_ref);
 		goto error2;
 	}
 
 	/* update the key */
-	ret = key_update(key, payload, plen);
+	ret = key_update(key_ref, payload, plen);
 
-	key_put(key);
+	key_ref_put(key_ref);
  error2:
 	kfree(payload);
  error:
@@ -349,19 +351,19 @@ long keyctl_update_key(key_serial_t id,
  */
 long keyctl_revoke_key(key_serial_t id)
 {
-	struct key *key;
+	key_ref_t key_ref;
 	long ret;
 
-	key = lookup_user_key(NULL, id, 0, 0, KEY_WRITE);
-	if (IS_ERR(key)) {
-		ret = PTR_ERR(key);
+	key_ref = lookup_user_key(NULL, id, 0, 0, KEY_WRITE);
+	if (IS_ERR(key_ref)) {
+		ret = PTR_ERR(key_ref);
 		goto error;
 	}
 
-	key_revoke(key);
+	key_revoke(key_ref_to_ptr(key_ref));
 	ret = 0;
 
-	key_put(key);
+	key_ref_put(key_ref);
  error:
 	return ret;
 
@@ -375,18 +377,18 @@ long keyctl_revoke_key(key_serial_t id)
  */
 long keyctl_keyring_clear(key_serial_t ringid)
 {
-	struct key *keyring;
+	key_ref_t keyring_ref;
 	long ret;
 
-	keyring = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE);
-	if (IS_ERR(keyring)) {
-		ret = PTR_ERR(keyring);
+	keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE);
+	if (IS_ERR(keyring_ref)) {
+		ret = PTR_ERR(keyring_ref);
 		goto error;
 	}
 
-	ret = keyring_clear(keyring);
+	ret = keyring_clear(key_ref_to_ptr(keyring_ref));
 
-	key_put(keyring);
+	key_ref_put(keyring_ref);
  error:
 	return ret;
 
@@ -401,26 +403,26 @@ long keyctl_keyring_clear(key_serial_t ringid)
  */
 long keyctl_keyring_link(key_serial_t id, key_serial_t ringid)
 {
-	struct key *keyring, *key;
+	key_ref_t keyring_ref, key_ref;
 	long ret;
 
-	keyring = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE);
-	if (IS_ERR(keyring)) {
-		ret = PTR_ERR(keyring);
+	keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE);
+	if (IS_ERR(keyring_ref)) {
+		ret = PTR_ERR(keyring_ref);
 		goto error;
 	}
 
-	key = lookup_user_key(NULL, id, 1, 0, KEY_LINK);
-	if (IS_ERR(key)) {
-		ret = PTR_ERR(key);
+	key_ref = lookup_user_key(NULL, id, 1, 0, KEY_LINK);
+	if (IS_ERR(key_ref)) {
+		ret = PTR_ERR(key_ref);
 		goto error2;
 	}
 
-	ret = key_link(keyring, key);
+	ret = key_link(key_ref_to_ptr(keyring_ref), key_ref_to_ptr(key_ref));
 
-	key_put(key);
+	key_ref_put(key_ref);
  error2:
-	key_put(keyring);
+	key_ref_put(keyring_ref);
  error:
 	return ret;
 
@@ -435,26 +437,26 @@ long keyctl_keyring_link(key_serial_t id, key_serial_t ringid)
  */
 long keyctl_keyring_unlink(key_serial_t id, key_serial_t ringid)
 {
-	struct key *keyring, *key;
+	key_ref_t keyring_ref, key_ref;
 	long ret;
 
-	keyring = lookup_user_key(NULL, ringid, 0, 0, KEY_WRITE);
-	if (IS_ERR(keyring)) {
-		ret = PTR_ERR(keyring);
+	keyring_ref = lookup_user_key(NULL, ringid, 0, 0, KEY_WRITE);
+	if (IS_ERR(keyring_ref)) {
+		ret = PTR_ERR(keyring_ref);
 		goto error;
 	}
 
-	key = lookup_user_key(NULL, id, 0, 0, 0);
-	if (IS_ERR(key)) {
-		ret = PTR_ERR(key);
+	key_ref = lookup_user_key(NULL, id, 0, 0, 0);
+	if (IS_ERR(key_ref)) {
+		ret = PTR_ERR(key_ref);
 		goto error2;
 	}
 
-	ret = key_unlink(keyring, key);
+	ret = key_unlink(key_ref_to_ptr(keyring_ref), key_ref_to_ptr(key_ref));
 
-	key_put(key);
+	key_ref_put(key_ref);
  error2:
-	key_put(keyring);
+	key_ref_put(keyring_ref);
  error:
 	return ret;
 
@@ -476,24 +478,26 @@ long keyctl_describe_key(key_serial_t keyid,
 			 size_t buflen)
 {
 	struct key *key, *instkey;
+	key_ref_t key_ref;
 	char *tmpbuf;
 	long ret;
 
-	key = lookup_user_key(NULL, keyid, 0, 1, KEY_VIEW);
-	if (IS_ERR(key)) {
+	key_ref = lookup_user_key(NULL, keyid, 0, 1, KEY_VIEW);
+	if (IS_ERR(key_ref)) {
 		/* viewing a key under construction is permitted if we have the
 		 * authorisation token handy */
-		if (PTR_ERR(key) == -EACCES) {
+		if (PTR_ERR(key_ref) == -EACCES) {
 			instkey = key_get_instantiation_authkey(keyid);
 			if (!IS_ERR(instkey)) {
 				key_put(instkey);
-				key = lookup_user_key(NULL, keyid, 0, 1, 0);
-				if (!IS_ERR(key))
+				key_ref = lookup_user_key(NULL, keyid,
+							  0, 1, 0);
+				if (!IS_ERR(key_ref))
 					goto okay;
 			}
 		}
 
-		ret = PTR_ERR(key);
+		ret = PTR_ERR(key_ref);
 		goto error;
 	}
 
@@ -504,13 +508,16 @@ okay:
 	if (!tmpbuf)
 		goto error2;
 
+	key = key_ref_to_ptr(key_ref);
+
 	ret = snprintf(tmpbuf, PAGE_SIZE - 1,
-		       "%s;%d;%d;%06x;%s",
-		       key->type->name,
-		       key->uid,
-		       key->gid,
-		       key->perm,
-		       key->description ? key->description :""
+		       "%s;%d;%d;%08x;%s",
+		       key_ref_to_ptr(key_ref)->type->name,
+		       key_ref_to_ptr(key_ref)->uid,
+		       key_ref_to_ptr(key_ref)->gid,
+		       key_ref_to_ptr(key_ref)->perm,
+		       key_ref_to_ptr(key_ref)->description ?
+		       key_ref_to_ptr(key_ref)->description : ""
 		       );
 
 	/* include a NUL char at the end of the data */
@@ -530,7 +537,7 @@ okay:
 
 	kfree(tmpbuf);
  error2:
-	key_put(key);
+	key_ref_put(key_ref);
  error:
 	return ret;
 
@@ -552,7 +559,7 @@ long keyctl_keyring_search(key_serial_t ringid,
 			   key_serial_t destringid)
 {
 	struct key_type *ktype;
-	struct key *keyring, *key, *dest;
+	key_ref_t keyring_ref, key_ref, dest_ref;
 	char type[32], *description;
 	long dlen, ret;
 
@@ -581,18 +588,18 @@ long keyctl_keyring_search(key_serial_t ringid,
 		goto error2;
 
 	/* get the keyring at which to begin the search */
-	keyring = lookup_user_key(NULL, ringid, 0, 0, KEY_SEARCH);
-	if (IS_ERR(keyring)) {
-		ret = PTR_ERR(keyring);
+	keyring_ref = lookup_user_key(NULL, ringid, 0, 0, KEY_SEARCH);
+	if (IS_ERR(keyring_ref)) {
+		ret = PTR_ERR(keyring_ref);
 		goto error2;
 	}
 
 	/* get the destination keyring if specified */
-	dest = NULL;
+	dest_ref = NULL;
 	if (destringid) {
-		dest = lookup_user_key(NULL, destringid, 1, 0, KEY_WRITE);
-		if (IS_ERR(dest)) {
-			ret = PTR_ERR(dest);
+		dest_ref = lookup_user_key(NULL, destringid, 1, 0, KEY_WRITE);
+		if (IS_ERR(dest_ref)) {
+			ret = PTR_ERR(dest_ref);
 			goto error3;
 		}
 	}
@@ -605,9 +612,9 @@ long keyctl_keyring_search(key_serial_t ringid,
 	}
 
 	/* do the search */
-	key = keyring_search(keyring, ktype, description);
-	if (IS_ERR(key)) {
-		ret = PTR_ERR(key);
+	key_ref = keyring_search(keyring_ref, ktype, description);
+	if (IS_ERR(key_ref)) {
+		ret = PTR_ERR(key_ref);
 
 		/* treat lack or presence of a negative key the same */
 		if (ret == -EAGAIN)
@@ -616,26 +623,26 @@ long keyctl_keyring_search(key_serial_t ringid,
 	}
 
 	/* link the resulting key to the destination keyring if we can */
-	if (dest) {
-		ret = -EACCES;
-		if (!key_permission(key, KEY_LINK))
+	if (dest_ref) {
+		ret = key_permission(key_ref, KEY_LINK);
+		if (ret < 0)
 			goto error6;
 
-		ret = key_link(dest, key);
+		ret = key_link(key_ref_to_ptr(dest_ref), key_ref_to_ptr(key_ref));
 		if (ret < 0)
 			goto error6;
 	}
 
-	ret = key->serial;
+	ret = key_ref_to_ptr(key_ref)->serial;
 
  error6:
-	key_put(key);
+	key_ref_put(key_ref);
  error5:
 	key_type_put(ktype);
  error4:
-	key_put(dest);
+	key_ref_put(dest_ref);
  error3:
-	key_put(keyring);
+	key_ref_put(keyring_ref);
  error2:
 	kfree(description);
  error:
@@ -643,16 +650,6 @@ long keyctl_keyring_search(key_serial_t ringid,
 
 } /* end keyctl_keyring_search() */
 
-/*****************************************************************************/
-/*
- * see if the key we're looking at is the target key
- */
-static int keyctl_read_key_same(const struct key *key, const void *target)
-{
-	return key == target;
-
-} /* end keyctl_read_key_same() */
-
 /*****************************************************************************/
 /*
  * read a user key's payload
@@ -665,38 +662,36 @@ static int keyctl_read_key_same(const struct key *key, const void *target)
  */
 long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen)
 {
-	struct key *key, *skey;
+	struct key *key;
+	key_ref_t key_ref;
 	long ret;
 
 	/* find the key first */
-	key = lookup_user_key(NULL, keyid, 0, 0, 0);
-	if (!IS_ERR(key)) {
-		/* see if we can read it directly */
-		if (key_permission(key, KEY_READ))
-			goto can_read_key;
-
-		/* we can't; see if it's searchable from this process's
-		 * keyrings
-		 * - we automatically take account of the fact that it may be
-		 *   dangling off an instantiation key
-		 */
-		skey = search_process_keyrings(key->type, key,
-					       keyctl_read_key_same, current);
-		if (!IS_ERR(skey))
-			goto can_read_key2;
-
-		ret = PTR_ERR(skey);
-		if (ret == -EAGAIN)
-			ret = -EACCES;
-		goto error2;
+	key_ref = lookup_user_key(NULL, keyid, 0, 0, 0);
+	if (IS_ERR(key_ref)) {
+		ret = -ENOKEY;
+		goto error;
 	}
 
-	ret = -ENOKEY;
-	goto error;
+	key = key_ref_to_ptr(key_ref);
+
+	/* see if we can read it directly */
+	ret = key_permission(key_ref, KEY_READ);
+	if (ret == 0)
+		goto can_read_key;
+	if (ret != -EACCES)
+		goto error;
+
+	/* we can't; see if it's searchable from this process's keyrings
+	 * - we automatically take account of the fact that it may be
+	 *   dangling off an instantiation key
+	 */
+	if (!is_key_possessed(key_ref)) {
+		ret = -EACCES;
+		goto error2;
+	}
 
 	/* the key is probably readable - now try to read it */
- can_read_key2:
-	key_put(skey);
  can_read_key:
 	ret = key_validate(key);
 	if (ret == 0) {
@@ -727,18 +722,21 @@ long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen)
 long keyctl_chown_key(key_serial_t id, uid_t uid, gid_t gid)
 {
 	struct key *key;
+	key_ref_t key_ref;
 	long ret;
 
 	ret = 0;
 	if (uid == (uid_t) -1 && gid == (gid_t) -1)
 		goto error;
 
-	key = lookup_user_key(NULL, id, 1, 1, 0);
-	if (IS_ERR(key)) {
-		ret = PTR_ERR(key);
+	key_ref = lookup_user_key(NULL, id, 1, 1, KEY_SETATTR);
+	if (IS_ERR(key_ref)) {
+		ret = PTR_ERR(key_ref);
 		goto error;
 	}
 
+	key = key_ref_to_ptr(key_ref);
+
 	/* make the changes with the locks held to prevent chown/chown races */
 	ret = -EACCES;
 	down_write(&key->sem);
@@ -784,18 +782,21 @@ long keyctl_chown_key(key_serial_t id, uid_t uid, gid_t gid)
 long keyctl_setperm_key(key_serial_t id, key_perm_t perm)
 {
 	struct key *key;
+	key_ref_t key_ref;
 	long ret;
 
 	ret = -EINVAL;
-	if (perm & ~(KEY_USR_ALL | KEY_GRP_ALL | KEY_OTH_ALL))
+	if (perm & ~(KEY_POS_ALL | KEY_USR_ALL | KEY_GRP_ALL | KEY_OTH_ALL))
 		goto error;
 
-	key = lookup_user_key(NULL, id, 1, 1, 0);
-	if (IS_ERR(key)) {
-		ret = PTR_ERR(key);
+	key_ref = lookup_user_key(NULL, id, 1, 1, KEY_SETATTR);
+	if (IS_ERR(key_ref)) {
+		ret = PTR_ERR(key_ref);
 		goto error;
 	}
 
+	key = key_ref_to_ptr(key_ref);
+
 	/* make the changes with the locks held to prevent chown/chmod races */
 	ret = -EACCES;
 	down_write(&key->sem);
@@ -824,7 +825,8 @@ long keyctl_instantiate_key(key_serial_t id,
 			    key_serial_t ringid)
 {
 	struct request_key_auth *rka;
-	struct key *instkey, *keyring;
+	struct key *instkey;
+	key_ref_t keyring_ref;
 	void *payload;
 	long ret;
 
@@ -832,6 +834,17 @@ long keyctl_instantiate_key(key_serial_t id,
 	if (plen > 32767)
 		goto error;
 
+	/* the appropriate instantiation authorisation key must have been
+	 * assumed before calling this */
+	ret = -EPERM;
+	instkey = current->request_key_auth;
+	if (!instkey)
+		goto error;
+
+	rka = instkey->payload.data;
+	if (rka->target_key->serial != id)
+		goto error;
+
 	/* pull the payload in if one was supplied */
 	payload = NULL;
 
@@ -846,37 +859,34 @@ long keyctl_instantiate_key(key_serial_t id,
 			goto error2;
 	}
 
-	/* find the instantiation authorisation key */
-	instkey = key_get_instantiation_authkey(id);
-	if (IS_ERR(instkey)) {
-		ret = PTR_ERR(instkey);
-		goto error2;
-	}
-
-	rka = instkey->payload.data;
-
 	/* find the destination keyring amongst those belonging to the
 	 * requesting task */
-	keyring = NULL;
+	keyring_ref = NULL;
 	if (ringid) {
-		keyring = lookup_user_key(rka->context, ringid, 1, 0,
-					  KEY_WRITE);
-		if (IS_ERR(keyring)) {
-			ret = PTR_ERR(keyring);
-			goto error3;
+		keyring_ref = lookup_user_key(rka->context, ringid, 1, 0,
+					      KEY_WRITE);
+		if (IS_ERR(keyring_ref)) {
+			ret = PTR_ERR(keyring_ref);
+			goto error2;
 		}
 	}
 
 	/* instantiate the key and link it into a keyring */
 	ret = key_instantiate_and_link(rka->target_key, payload, plen,
-				       keyring, instkey);
+				       key_ref_to_ptr(keyring_ref), instkey);
 
-	key_put(keyring);
- error3:
-	key_put(instkey);
- error2:
+	key_ref_put(keyring_ref);
+
+	/* discard the assumed authority if it's just been disabled by
+	 * instantiation of the key */
+	if (ret == 0) {
+		key_put(current->request_key_auth);
+		current->request_key_auth = NULL;
+	}
+
+error2:
 	kfree(payload);
- error:
+error:
 	return ret;
 
 } /* end keyctl_instantiate_key() */
@@ -889,36 +899,46 @@ long keyctl_instantiate_key(key_serial_t id,
 long keyctl_negate_key(key_serial_t id, unsigned timeout, key_serial_t ringid)
 {
 	struct request_key_auth *rka;
-	struct key *instkey, *keyring;
+	struct key *instkey;
+	key_ref_t keyring_ref;
 	long ret;
 
-	/* find the instantiation authorisation key */
-	instkey = key_get_instantiation_authkey(id);
-	if (IS_ERR(instkey)) {
-		ret = PTR_ERR(instkey);
+	/* the appropriate instantiation authorisation key must have been
+	 * assumed before calling this */
+	ret = -EPERM;
+	instkey = current->request_key_auth;
+	if (!instkey)
 		goto error;
-	}
 
 	rka = instkey->payload.data;
+	if (rka->target_key->serial != id)
+		goto error;
 
 	/* find the destination keyring if present (which must also be
 	 * writable) */
-	keyring = NULL;
+	keyring_ref = NULL;
 	if (ringid) {
-		keyring = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE);
-		if (IS_ERR(keyring)) {
-			ret = PTR_ERR(keyring);
-			goto error2;
+		keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE);
+		if (IS_ERR(keyring_ref)) {
+			ret = PTR_ERR(keyring_ref);
+			goto error;
 		}
 	}
 
 	/* instantiate the key and link it into a keyring */
-	ret = key_negate_and_link(rka->target_key, timeout, keyring, instkey);
+	ret = key_negate_and_link(rka->target_key, timeout,
+				  key_ref_to_ptr(keyring_ref), instkey);
 
-	key_put(keyring);
- error2:
-	key_put(instkey);
- error:
+	key_ref_put(keyring_ref);
+
+	/* discard the assumed authority if it's just been disabled by
+	 * instantiation of the key */
+	if (ret == 0) {
+		key_put(current->request_key_auth);
+		current->request_key_auth = NULL;
+	}
+
+error:
 	return ret;
 
 } /* end keyctl_negate_key() */
@@ -961,6 +981,88 @@ long keyctl_set_reqkey_keyring(int reqkey_defl)
 
 } /* end keyctl_set_reqkey_keyring() */
 
+/*****************************************************************************/
+/*
+ * set or clear the timeout for a key
+ */
+long keyctl_set_timeout(key_serial_t id, unsigned timeout)
+{
+	struct timespec now;
+	struct key *key;
+	key_ref_t key_ref;
+	time_t expiry;
+	long ret;
+
+	key_ref = lookup_user_key(NULL, id, 1, 1, KEY_SETATTR);
+	if (IS_ERR(key_ref)) {
+		ret = PTR_ERR(key_ref);
+		goto error;
+	}
+
+	key = key_ref_to_ptr(key_ref);
+
+	/* make the changes with the locks held to prevent races */
+	down_write(&key->sem);
+
+	expiry = 0;
+	if (timeout > 0) {
+		now = current_kernel_time();
+		expiry = now.tv_sec + timeout;
+	}
+
+	key->expiry = expiry;
+
+	up_write(&key->sem);
+	key_put(key);
+
+	ret = 0;
+error:
+	return ret;
+
+} /* end keyctl_set_timeout() */
+
+/*****************************************************************************/
+/*
+ * assume the authority to instantiate the specified key
+ */
+long keyctl_assume_authority(key_serial_t id)
+{
+	struct key *authkey;
+	long ret;
+
+	/* special key IDs aren't permitted */
+	ret = -EINVAL;
+	if (id < 0)
+		goto error;
+
+	/* we divest ourselves of authority if given an ID of 0 */
+	if (id == 0) {
+		key_put(current->request_key_auth);
+		current->request_key_auth = NULL;
+		ret = 0;
+		goto error;
+	}
+
+	/* attempt to assume the authority temporarily granted to us whilst we
+	 * instantiate the specified key
+	 * - the authorisation key must be in the current task's keyrings
+	 *   somewhere
+	 */
+	authkey = key_get_instantiation_authkey(id);
+	if (IS_ERR(authkey)) {
+		ret = PTR_ERR(authkey);
+		goto error;
+	}
+
+	key_put(current->request_key_auth);
+	current->request_key_auth = authkey;
+	ret = authkey->serial;
+
+error:
+	return ret;
+
+} /* end keyctl_assume_authority() */
+
 /*****************************************************************************/
 /*
  * the key control system call
@@ -1034,6 +1136,13 @@ asmlinkage long sys_keyctl(int option, unsigned long arg2, unsigned long arg3,
 	case KEYCTL_SET_REQKEY_KEYRING:
 		return keyctl_set_reqkey_keyring(arg2);
 
+	case KEYCTL_SET_TIMEOUT:
+		return keyctl_set_timeout((key_serial_t) arg2,
+					  (unsigned) arg3);
+
+	case KEYCTL_ASSUME_AUTHORITY:
+		return keyctl_assume_authority((key_serial_t) arg2);
+
 	default:
 		return -EOPNOTSUPP;
 	}