#include <linux/module.h>
#include <linux/init.h>
-#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/seq_file.h>
#include <linux/err.h>
+#include <keys/user-type.h>
#include <asm/uaccess.h>
#include "internal.h"
-static int user_instantiate(struct key *key, const void *data, size_t datalen);
-static int user_duplicate(struct key *key, const struct key *source);
-static int user_update(struct key *key, const void *data, size_t datalen);
-static int user_match(const struct key *key, const void *criterion);
-static void user_destroy(struct key *key);
-static void user_describe(const struct key *user, struct seq_file *m);
-static long user_read(const struct key *key,
- char __user *buffer, size_t buflen);
-
/*
* user defined keys take an arbitrary string as the description and an
* arbitrary blob of data as the payload
struct key_type key_type_user = {
.name = "user",
.instantiate = user_instantiate,
- .duplicate = user_duplicate,
.update = user_update,
.match = user_match,
+ .revoke = user_revoke,
.destroy = user_destroy,
.describe = user_describe,
.read = user_read,
};
-struct user_key_payload {
- struct rcu_head rcu; /* RCU destructor */
- unsigned short datalen; /* length of this data */
- char data[0]; /* actual data */
-};
+EXPORT_SYMBOL_GPL(key_type_user);
-/*****************************************************************************/
/*
* instantiate a user defined key
*/
-static int user_instantiate(struct key *key, const void *data, size_t datalen)
+int user_instantiate(struct key *key, const void *data, size_t datalen)
{
struct user_key_payload *upayload;
int ret;
rcu_assign_pointer(key->payload.data, upayload);
ret = 0;
- error:
- return ret;
-
-} /* end user_instantiate() */
-
-/*****************************************************************************/
-/*
- * duplicate a user defined key
- * - both keys' semaphores are locked against further modification
- * - the new key cannot yet be accessed
- */
-static int user_duplicate(struct key *key, const struct key *source)
-{
- struct user_key_payload *upayload, *spayload;
- int ret;
-
- /* just copy the payload */
- ret = -ENOMEM;
- upayload = kmalloc(sizeof(*upayload) + source->datalen, GFP_KERNEL);
- if (upayload) {
- spayload = rcu_dereference(source->payload.data);
- BUG_ON(source->datalen != spayload->datalen);
-
- upayload->datalen = key->datalen = spayload->datalen;
- memcpy(upayload->data, spayload->data, key->datalen);
-
- key->payload.data = upayload;
- ret = 0;
- }
-
+error:
return ret;
+}
-} /* end user_duplicate() */
-
-/*****************************************************************************/
-/*
- * dispose of the old data from an updated user defined key
- */
-static void user_update_rcu_disposal(struct rcu_head *rcu)
-{
- struct user_key_payload *upayload;
-
- upayload = container_of(rcu, struct user_key_payload, rcu);
+EXPORT_SYMBOL_GPL(user_instantiate);
- kfree(upayload);
-
-} /* end user_update_rcu_disposal() */
-
-/*****************************************************************************/
/*
* update a user defined key
* - the key's semaphore is write-locked
*/
-static int user_update(struct key *key, const void *data, size_t datalen)
+int user_update(struct key *key, const void *data, size_t datalen)
{
struct user_key_payload *upayload, *zap;
int ret;
key->expiry = 0;
}
- call_rcu(&zap->rcu, user_update_rcu_disposal);
+ kfree_rcu(zap, rcu);
- error:
+error:
return ret;
+}
-} /* end user_update() */
+EXPORT_SYMBOL_GPL(user_update);
-/*****************************************************************************/
/*
* match users on their name
*/
-static int user_match(const struct key *key, const void *description)
+int user_match(const struct key *key, const void *description)
{
return strcmp(key->description, description) == 0;
+}
+
+EXPORT_SYMBOL_GPL(user_match);
+
+/*
+ * dispose of the links from a revoked keyring
+ * - called with the key sem write-locked
+ */
+void user_revoke(struct key *key)
+{
+ struct user_key_payload *upayload = key->payload.data;
-} /* end user_match() */
+ /* clear the quota */
+ key_payload_reserve(key, 0);
+
+ if (upayload) {
+ rcu_assign_pointer(key->payload.data, NULL);
+ kfree_rcu(upayload, rcu);
+ }
+}
+
+EXPORT_SYMBOL(user_revoke);
-/*****************************************************************************/
/*
- * dispose of the data dangling from the corpse of a user
+ * dispose of the data dangling from the corpse of a user key
*/
-static void user_destroy(struct key *key)
+void user_destroy(struct key *key)
{
struct user_key_payload *upayload = key->payload.data;
kfree(upayload);
+}
-} /* end user_destroy() */
+EXPORT_SYMBOL_GPL(user_destroy);
-/*****************************************************************************/
/*
* describe the user key
*/
-static void user_describe(const struct key *key, struct seq_file *m)
+void user_describe(const struct key *key, struct seq_file *m)
{
seq_puts(m, key->description);
+ if (key_is_instantiated(key))
+ seq_printf(m, ": %u", key->datalen);
+}
- seq_printf(m, ": %u", key->datalen);
-
-} /* end user_describe() */
+EXPORT_SYMBOL_GPL(user_describe);
-/*****************************************************************************/
/*
* read the key data
* - the key's semaphore is read-locked
*/
-static long user_read(const struct key *key,
- char __user *buffer, size_t buflen)
+long user_read(const struct key *key, char __user *buffer, size_t buflen)
{
struct user_key_payload *upayload;
long ret;
- upayload = rcu_dereference(key->payload.data);
+ upayload = rcu_dereference_key(key);
ret = upayload->datalen;
/* we can return the data as is */
}
return ret;
+}
-} /* end user_read() */
+EXPORT_SYMBOL_GPL(user_read);
Code Review / linux-3.10.git / blobdiff