tlshd: Clean up logic in tlshd_start_tls_handshake()

gnutls_handshake() is supposed to return only a GNUTLS_E value, and
the session_status field is supposed to contain only a positive
errno.

GNUTLS_E_PREMATURE_TERMINATION is -110. It turns out that on x86,
-ETIMEDOUT is also -110. Make sure the correct symbolic constants
and auditing functions are utilized.

Fixes: b010190 ("tlshd: Pass ETIMEDOUT from gnutls to kernel")
Reviewed-by: Benjamin Coddington <[email protected]>
Signed-off-by: Chuck Lever <[email protected]>

Author: chucklever

src/tlshd/handshake.c

@@ -97,12 +97,12 @@ void tlshd_start_tls_handshake(gnutls_session_t session,
 		case GNUTLS_E_CERTIFICATE_VERIFICATION_ERROR:
 			tlshd_log_cert_verification_error(session);
 			break;
-		case -ETIMEDOUT:
-			tlshd_log_gnutls_error(ret);
-			parms->session_status = -ret;
+		case GNUTLS_E_PREMATURE_TERMINATION:
+			tlshd_log_error("Handshake timeout, retrying");
+			parms->session_status = ETIMEDOUT;
 			break;
 		default:
-			tlshd_log_notice("tlshd_start_tls_handshake unhandled error %d, returning EACCES\n", ret);
+			tlshd_log_gnutls_error(ret);
 		}
 		return;
 	}