[PATCH] keys: Permit key expiry time to be set
Add a new keyctl function that allows the expiry time to be set on a key or
removed from a key, provided the caller has attribute modification access.
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Alexander Zangerl <az@bond.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/security/keys/compat.c b/security/keys/compat.c
index 3303673..e8e7ef4 100644
--- a/security/keys/compat.c
+++ b/security/keys/compat.c
@@ -74,6 +74,9 @@
case KEYCTL_SET_REQKEY_KEYRING:
return keyctl_set_reqkey_keyring(arg2);
+ case KEYCTL_SET_TIMEOUT:
+ return keyctl_set_timeout(arg2, arg3);
+
default:
return -EOPNOTSUPP;
}
diff --git a/security/keys/internal.h b/security/keys/internal.h
index 39cba97..51f37c0 100644
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -136,6 +136,7 @@
size_t, key_serial_t);
extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t);
extern long keyctl_set_reqkey_keyring(int);
+extern long keyctl_set_timeout(key_serial_t, unsigned);
/*
diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
index b7a468f..299f0ae1 100644
--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -967,6 +967,46 @@
/*****************************************************************************/
/*
+ * 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() */
+
+/*****************************************************************************/
+/*
* the key control system call
*/
asmlinkage long sys_keyctl(int option, unsigned long arg2, unsigned long arg3,
@@ -1038,6 +1078,10 @@
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);
+
default:
return -EOPNOTSUPP;
}