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Diffstat (limited to 'net/dns_resolver/dns_key.c')
-rw-r--r--net/dns_resolver/dns_key.c63
1 files changed, 36 insertions, 27 deletions
diff --git a/net/dns_resolver/dns_key.c b/net/dns_resolver/dns_key.c
index 739435a6af3..bf858433904 100644
--- a/net/dns_resolver/dns_key.c
+++ b/net/dns_resolver/dns_key.c
@@ -19,8 +19,7 @@
* the GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
- * along with this library; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
@@ -38,7 +37,7 @@ MODULE_DESCRIPTION("DNS Resolver");
MODULE_AUTHOR("Wang Lei");
MODULE_LICENSE("GPL");
-unsigned dns_resolver_debug;
+unsigned int dns_resolver_debug;
module_param_named(debug, dns_resolver_debug, uint, S_IWUSR | S_IRUGO);
MODULE_PARM_DESC(debug, "DNS Resolver debugging mask");
@@ -59,16 +58,17 @@ const struct cred *dns_resolver_cache;
* "ip1,ip2,...#foo=bar"
*/
static int
-dns_resolver_instantiate(struct key *key, const void *_data, size_t datalen)
+dns_resolver_instantiate(struct key *key, struct key_preparsed_payload *prep)
{
struct user_key_payload *upayload;
unsigned long derrno;
int ret;
- size_t result_len = 0;
- const char *data = _data, *end, *opt;
+ size_t datalen = prep->datalen, result_len = 0;
+ const char *data = prep->data, *end, *opt;
- kenter("%%%d,%s,'%s',%zu",
- key->serial, key->description, data, datalen);
+ kenter("%%%d,%s,'%*.*s',%zu",
+ key->serial, key->description,
+ (int)datalen, (int)datalen, data, datalen);
if (datalen <= 1 || !data || data[datalen - 1] != '\0')
return -EINVAL;
@@ -117,7 +117,7 @@ dns_resolver_instantiate(struct key *key, const void *_data, size_t datalen)
if (opt_vlen <= 0)
goto bad_option_value;
- ret = strict_strtoul(eq, 10, &derrno);
+ ret = kstrtoul(eq, 10, &derrno);
if (ret < 0)
goto bad_option_value;
@@ -211,10 +211,25 @@ static void dns_resolver_describe(const struct key *key, struct seq_file *m)
int err = key->type_data.x[0];
seq_puts(m, key->description);
- if (err)
- seq_printf(m, ": %d", err);
- else
- seq_printf(m, ": %u", key->datalen);
+ if (key_is_instantiated(key)) {
+ if (err)
+ seq_printf(m, ": %d", err);
+ else
+ seq_printf(m, ": %u", key->datalen);
+ }
+}
+
+/*
+ * read the DNS data
+ * - the key's semaphore is read-locked
+ */
+static long dns_resolver_read(const struct key *key,
+ char __user *buffer, size_t buflen)
+{
+ if (key->type_data.x[0])
+ return key->type_data.x[0];
+
+ return user_read(key, buffer, buflen);
}
struct key_type key_type_dns_resolver = {
@@ -224,7 +239,7 @@ struct key_type key_type_dns_resolver = {
.revoke = user_revoke,
.destroy = user_destroy,
.describe = dns_resolver_describe,
- .read = user_read,
+ .read = dns_resolver_read,
};
static int __init init_dns_resolver(void)
@@ -233,9 +248,6 @@ static int __init init_dns_resolver(void)
struct key *keyring;
int ret;
- printk(KERN_NOTICE "Registering the %s key type\n",
- key_type_dns_resolver.name);
-
/* create an override credential set with a special thread keyring in
* which DNS requests are cached
*
@@ -246,25 +258,23 @@ static int __init init_dns_resolver(void)
if (!cred)
return -ENOMEM;
- keyring = key_alloc(&key_type_keyring, ".dns_resolver", 0, 0, cred,
- (KEY_POS_ALL & ~KEY_POS_SETATTR) |
- KEY_USR_VIEW | KEY_USR_READ,
- KEY_ALLOC_NOT_IN_QUOTA);
+ keyring = keyring_alloc(".dns_resolver",
+ GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
+ (KEY_POS_ALL & ~KEY_POS_SETATTR) |
+ KEY_USR_VIEW | KEY_USR_READ,
+ KEY_ALLOC_NOT_IN_QUOTA, NULL);
if (IS_ERR(keyring)) {
ret = PTR_ERR(keyring);
goto failed_put_cred;
}
- ret = key_instantiate_and_link(keyring, NULL, 0, NULL, NULL);
- if (ret < 0)
- goto failed_put_key;
-
ret = register_key_type(&key_type_dns_resolver);
if (ret < 0)
goto failed_put_key;
/* instruct request_key() to use this special keyring as a cache for
* the results it looks up */
+ set_bit(KEY_FLAG_ROOT_CAN_CLEAR, &keyring->flags);
cred->thread_keyring = keyring;
cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING;
dns_resolver_cache = cred;
@@ -284,10 +294,9 @@ static void __exit exit_dns_resolver(void)
key_revoke(dns_resolver_cache->thread_keyring);
unregister_key_type(&key_type_dns_resolver);
put_cred(dns_resolver_cache);
- printk(KERN_NOTICE "Unregistered %s key type\n",
- key_type_dns_resolver.name);
}
module_init(init_dns_resolver)
module_exit(exit_dns_resolver)
MODULE_LICENSE("GPL");
+