-/* keyring.c: keyring handling
+/* Keyring handling
*
- * Copyright (C) 2004-5 Red Hat, Inc. All Rights Reserved.
+ * Copyright (C) 2004-2005, 2008 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
static int keyring_instantiate(struct key *keyring,
const void *data, size_t datalen);
static int keyring_match(const struct key *keyring, const void *criterion);
+static void keyring_revoke(struct key *keyring);
static void keyring_destroy(struct key *keyring);
static void keyring_describe(const struct key *keyring, struct seq_file *m);
static long keyring_read(const struct key *keyring,
.def_datalen = sizeof(struct keyring_list),
.instantiate = keyring_instantiate,
.match = keyring_match,
+ .revoke = keyring_revoke,
.destroy = keyring_destroy,
.describe = keyring_describe,
.read = keyring_read,
};
+EXPORT_SYMBOL(key_type_keyring);
+
/*
* semaphore to serialise link/link calls to prevent two link calls in parallel
* introducing a cycle
* publish the name of a keyring so that it can be found by name (if it has
* one)
*/
-void keyring_publish_name(struct key *keyring)
+static void keyring_publish_name(struct key *keyring)
{
int bucket;
* allocate a keyring and link into the destination keyring
*/
struct key *keyring_alloc(const char *description, uid_t uid, gid_t gid,
- struct task_struct *ctx, int not_in_quota,
+ struct task_struct *ctx, unsigned long flags,
struct key *dest)
{
struct key *keyring;
keyring = key_alloc(&key_type_keyring, description,
uid, gid, ctx,
(KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL,
- not_in_quota);
+ flags);
if (!IS_ERR(keyring)) {
ret = key_instantiate_and_link(keyring, NULL, 0, dest, NULL);
struct keyring_list *keylist;
struct timespec now;
- unsigned long possessed;
+ unsigned long possessed, kflags;
struct key *keyring, *key;
key_ref_t key_ref;
long err;
err = -EAGAIN;
sp = 0;
+ /* firstly we should check to see if this top-level keyring is what we
+ * are looking for */
+ key_ref = ERR_PTR(-EAGAIN);
+ kflags = keyring->flags;
+ if (keyring->type == type && match(keyring, description)) {
+ key = keyring;
+
+ /* check it isn't negative and hasn't expired or been
+ * revoked */
+ if (kflags & (1 << KEY_FLAG_REVOKED))
+ goto error_2;
+ if (key->expiry && now.tv_sec >= key->expiry)
+ goto error_2;
+ key_ref = ERR_PTR(-ENOKEY);
+ if (kflags & (1 << KEY_FLAG_NEGATIVE))
+ goto error_2;
+ goto found;
+ }
+
+ /* otherwise, the top keyring must not be revoked, expired, or
+ * negatively instantiated if we are to search it */
+ key_ref = ERR_PTR(-EAGAIN);
+ if (kflags & ((1 << KEY_FLAG_REVOKED) | (1 << KEY_FLAG_NEGATIVE)) ||
+ (keyring->expiry && now.tv_sec >= keyring->expiry))
+ goto error_2;
+
/* start processing a new keyring */
descend:
if (test_bit(KEY_FLAG_REVOKED, &keyring->flags))
/* iterate through the keys in this keyring first */
for (kix = 0; kix < keylist->nkeys; kix++) {
key = keylist->keys[kix];
+ kflags = key->flags;
/* ignore keys not of this type */
if (key->type != type)
continue;
/* skip revoked keys and expired keys */
- if (test_bit(KEY_FLAG_REVOKED, &key->flags))
+ if (kflags & (1 << KEY_FLAG_REVOKED))
continue;
if (key->expiry && now.tv_sec >= key->expiry)
context, KEY_SEARCH) < 0)
continue;
- /* we set a different error code if we find a negative key */
- if (test_bit(KEY_FLAG_NEGATIVE, &key->flags)) {
+ /* we set a different error code if we pass a negative key */
+ if (kflags & (1 << KEY_FLAG_NEGATIVE)) {
err = -ENOKEY;
continue;
}
/*
* find a keyring with the specified name
* - all named keyrings are searched
- * - only find keyrings with search permission for the process
- * - only find keyrings with a serial number greater than the one specified
+ * - normally only finds keyrings with search permission for the current process
*/
-struct key *find_keyring_by_name(const char *name, key_serial_t bound)
+struct key *find_keyring_by_name(const char *name, bool skip_perm_check)
{
struct key *keyring;
int bucket;
if (strcmp(keyring->description, name) != 0)
continue;
- if (key_permission(make_key_ref(keyring, 0),
+ if (!skip_perm_check &&
+ key_permission(make_key_ref(keyring, 0),
KEY_SEARCH) < 0)
continue;
- /* found a potential candidate, but we still need to
- * check the serial number */
- if (keyring->serial <= bound)
- continue;
-
/* we've got a match */
atomic_inc(&keyring->usage);
read_unlock(&keyring_name_lock);
BUG_ON(size > PAGE_SIZE);
ret = -ENOMEM;
- nklist = kmalloc(size, GFP_KERNEL);
+ nklist = kmemdup(klist, size, GFP_KERNEL);
if (!nklist)
goto error2;
- memcpy(nklist, klist, size);
-
/* replace matched key */
atomic_inc(&key->usage);
nklist->keys[loop] = key;
} /* end keyring_clear() */
EXPORT_SYMBOL(keyring_clear);
+
+/*****************************************************************************/
+/*
+ * dispose of the links from a revoked keyring
+ * - called with the key sem write-locked
+ */
+static void keyring_revoke(struct key *keyring)
+{
+ struct keyring_list *klist = keyring->payload.subscriptions;
+
+ /* adjust the quota */
+ key_payload_reserve(keyring, 0);
+
+ if (klist) {
+ rcu_assign_pointer(keyring->payload.subscriptions, NULL);
+ call_rcu(&klist->rcu, keyring_clear_rcu_disposal);
+ }
+
+} /* end keyring_revoke() */