SUNRPC: pass a keyring serial number to the TLS handshake

The handshake upcall links the keyring named in ta_keyring into
tlshd's process keyring before tlshd reads the client certificate and
private key. That link is how tlshd gains possession of keys that
grant no user read permission. xprtsock never fills the field, so an
x509 handshake can present only keys that tlshd's own credentials can
read.

Add a keyring serial number to struct xprtsec_parms and pass it to
the x509 handshake, so an RPC client can name the keyring that holds
its credentials.

Signed-off-by: Chuck Lever <cel@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@hammerspace.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h
index a82045804d34..005730623f3b 100644
--- a/include/linux/sunrpc/xprt.h
+++ b/include/linux/sunrpc/xprt.h
@@ -145,6 +145,7 @@ struct xprtsec_parms {
 	enum xprtsec_policies	policy;
 
 	/* authentication material */
+	key_serial_t		keyring_serial;
 	key_serial_t		cert_serial;
 	key_serial_t		privkey_serial;
 };