[PATCH 3.10 076/268] libceph: verify authorize reply on connect

Willy Tarreau
2017-06-19T18:47:23Z

From: Ilya Dryomov <idryomov@gmail.com>

commit 5c056fdc5b474329037f2aa18401bd73033e0ce0 upstream.

After sending an authorizer (ceph_x_authorize_a + ceph_x_authorize_b),
the client gets back a ceph_x_authorize_reply, which it is supposed to
verify to ensure the authenticity and protect against replay attacks.
The code for doing this is there (ceph_x_verify_authorizer_reply(),
ceph_auth_verify_authorizer_reply() + plumbing), but it is never
invoked by the the messenger.

AFAICT this goes back to 2009, when ceph authentication protocols
support was added to the kernel client in 4e7a5dcd1bba ("ceph:
negotiate authentication protocol; implement AUTH_NONE protocol").

The second param of ceph_connection_operations::verify_authorizer_reply
is unused all the way down. Pass 0 to facilitate backporting, and kill
it in the next commit.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Sage Weil <sage@redhat.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Willy Tarreau <w@1wt.eu>
---
net/ceph/messenger.c | 13 +++++++++++++
1 file changed, 13 insertions(+)

diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 025ced8..7104750 100644
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -1969,6 +1969,19 @@ static int process_connect(struct ceph_connection *con)

dout("process_connect on %p tag %d\n", con, (int)con->in_tag);

+ if (con->auth_reply_buf) {
+ /*
+ * Any connection that defines ->get_authorizer()
+ * should also define ->verify_authorizer_reply().
+ * See get_connect_authorizer().
+ */
+ ret = con->ops->verify_authorizer_reply(con, 0);
+ if (ret < 0) {
+ con->error_msg = "bad authorize reply";
+ return ret;
+ }
+ }
+
switch (con->in_reply.tag) {
case CEPH_MSGR_TAG_FEATURES:
pr_err("%s%lld %s feature set mismatch,"
--
2.8.0.rc2.1.gbe9624a