[PATCH 05/12] KEYS: user: Use key preparsing

From: David Howells
Date: Thu Mar 20 2014 - 08:05:29 EST


Make use of key preparsing in user-defined and logon keys so that quota size
determination can take place prior to keyring locking when a key is being
added.

Also the idmapper key types need to change to match as they use the
user-defined key type routines.

Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
---

fs/nfs/idmap.c | 8 ++++++--
include/keys/user-type.h | 3 ++-
security/keys/user_defined.c | 41 ++++++++++++++++++++++-------------------
3 files changed, 30 insertions(+), 22 deletions(-)

diff --git a/fs/nfs/idmap.c b/fs/nfs/idmap.c
index 567983d2c0eb..59b217a3266d 100644
--- a/fs/nfs/idmap.c
+++ b/fs/nfs/idmap.c
@@ -174,7 +174,9 @@ static int nfs_map_numeric_to_string(__u32 id, char *buf, size_t buflen)

static struct key_type key_type_id_resolver = {
.name = "id_resolver",
- .instantiate = user_instantiate,
+ .preparse = user_preparse,
+ .free_preparse = user_free_preparse,
+ .instantiate = generic_key_instantiate,
.match = user_match,
.revoke = user_revoke,
.destroy = user_destroy,
@@ -394,7 +396,9 @@ static const struct rpc_pipe_ops idmap_upcall_ops = {

static struct key_type key_type_id_resolver_legacy = {
.name = "id_legacy",
- .instantiate = user_instantiate,
+ .preparse = user_preparse,
+ .free_preparse = user_free_preparse,
+ .instantiate = generic_key_instantiate,
.match = user_match,
.revoke = user_revoke,
.destroy = user_destroy,
diff --git a/include/keys/user-type.h b/include/keys/user-type.h
index 5e452c84f1e6..3ab1873a4bfa 100644
--- a/include/keys/user-type.h
+++ b/include/keys/user-type.h
@@ -37,7 +37,8 @@ extern struct key_type key_type_logon;

struct key_preparsed_payload;

-extern int user_instantiate(struct key *key, struct key_preparsed_payload *prep);
+extern int user_preparse(struct key_preparsed_payload *prep);
+extern void user_free_preparse(struct key_preparsed_payload *prep);
extern int user_update(struct key *key, struct key_preparsed_payload *prep);
extern int user_match(const struct key *key, const void *criterion);
extern void user_revoke(struct key *key);
diff --git a/security/keys/user_defined.c b/security/keys/user_defined.c
index faa2caeb593f..eee340011f2b 100644
--- a/security/keys/user_defined.c
+++ b/security/keys/user_defined.c
@@ -27,7 +27,9 @@ static int logon_vet_description(const char *desc);
struct key_type key_type_user = {
.name = "user",
.def_lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT,
- .instantiate = user_instantiate,
+ .preparse = user_preparse,
+ .free_preparse = user_free_preparse,
+ .instantiate = generic_key_instantiate,
.update = user_update,
.match = user_match,
.revoke = user_revoke,
@@ -47,7 +49,9 @@ EXPORT_SYMBOL_GPL(key_type_user);
struct key_type key_type_logon = {
.name = "logon",
.def_lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT,
- .instantiate = user_instantiate,
+ .preparse = user_preparse,
+ .free_preparse = user_free_preparse,
+ .instantiate = generic_key_instantiate,
.update = user_update,
.match = user_match,
.revoke = user_revoke,
@@ -58,38 +62,37 @@ struct key_type key_type_logon = {
EXPORT_SYMBOL_GPL(key_type_logon);

/*
- * instantiate a user defined key
+ * Preparse a user defined key payload
*/
-int user_instantiate(struct key *key, struct key_preparsed_payload *prep)
+int user_preparse(struct key_preparsed_payload *prep)
{
struct user_key_payload *upayload;
size_t datalen = prep->datalen;
- int ret;

- ret = -EINVAL;
if (datalen <= 0 || datalen > 32767 || !prep->data)
- goto error;
-
- ret = key_payload_reserve(key, datalen);
- if (ret < 0)
- goto error;
+ return -EINVAL;

- ret = -ENOMEM;
upayload = kmalloc(sizeof(*upayload) + datalen, GFP_KERNEL);
if (!upayload)
- goto error;
+ return -ENOMEM;

/* attach the data */
+ prep->quotalen = datalen;
+ prep->payload[0] = upayload;
upayload->datalen = datalen;
memcpy(upayload->data, prep->data, datalen);
- rcu_assign_keypointer(key, upayload);
- ret = 0;
-
-error:
- return ret;
+ return 0;
}
+EXPORT_SYMBOL_GPL(user_preparse);

-EXPORT_SYMBOL_GPL(user_instantiate);
+/*
+ * Free a preparse of a user defined key payload
+ */
+void user_free_preparse(struct key_preparsed_payload *prep)
+{
+ kfree(prep->payload[0]);
+}
+EXPORT_SYMBOL_GPL(user_free_preparse);

/*
* update a user defined key

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