Keep around a list of sequence numbers so the client can better handle the case
where a there are several retransmissions before the server responds to the
original request.



diff -puN include/linux/sunrpc/sched.h~clnt-remember-more-seqnos include/linux/sunrpc/sched.h
diff -puN net/sunrpc/auth_gss/auth_gss.c~clnt-remember-more-seqnos net/sunrpc/auth_gss/auth_gss.c
--- linux-2.5.72/net/sunrpc/auth_gss/auth_gss.c~clnt-remember-more-seqnos	2003-06-19 18:38:57.000000000 -0400
+++ linux-2.5.72-bfields/net/sunrpc/auth_gss/auth_gss.c	2003-06-19 18:38:57.000000000 -0400
@@ -592,6 +592,15 @@ gss_match(struct auth_cred *acred, struc
 	return (rc->cr_uid == acred->uid);
 }
 
+static void
+shift_seqnos(u32 *seqnos)
+{
+	int i;
+
+	for (i=1; i < GSS_SEQNO_CACHE; i++)
+		seqnos[i] = seqnos[i-1];
+}
+
 /*
 * Marshal credentials.
 * Maybe we should keep a cached credential for performance reasons.
@@ -622,13 +631,14 @@ gss_marshal(struct rpc_task *task, u32 *
 			gss_cred->gc_flavor);
 		goto out_put_ctx;
 	}
+	shift_seqnos(req->rq_seqnos);
 	spin_lock(&ctx->gc_seq_lock);
-	req->rq_seqno = ctx->gc_seq++;
+	req->rq_seqnos[0] = ctx->gc_seq++;
 	spin_unlock(&ctx->gc_seq_lock);
 
 	*p++ = htonl((u32) RPC_GSS_VERSION);
 	*p++ = htonl((u32) ctx->gc_proc);
-	*p++ = htonl((u32) req->rq_seqno);
+	*p++ = htonl((u32) req->rq_seqnos[0]);
 	*p++ = htonl((u32) service);
 	p = xdr_encode_netobj(p, &ctx->gc_wire_ctx);
 	*cred_len = htonl((p - (cred_len + 1)) << 2);
@@ -682,6 +692,32 @@ out:
 	return err;
 }
 
+static int
+verify_checksum(struct gss_ctx *ctx, struct xdr_netobj *mic, u32 *seqnos)
+{
+	u32		seq, qop_state;
+	struct xdr_buf	verf_buf;
+	struct iovec	iov;
+	int		i;
+
+	for (i=0; i < GSS_SEQNO_CACHE; i++) {
+		if (i && !seqnos[i])
+			goto fail;
+		seq = htonl(seqnos[i]);
+		iov.iov_base = &seq;
+		iov.iov_len = sizeof(seq);
+		xdr_buf_from_iov(&iov, &verf_buf);
+		if (!gss_verify_mic(ctx, &verf_buf, mic, &qop_state))
+			goto success;
+	}
+fail:
+	return -1;
+success:
+	/* So unwrap knows which seqno we used: */
+	seqnos[0] = seqnos[i];
+	return 0;
+}
+
 static u32 *
 gss_validate(struct rpc_task *task, u32 *p)
 {
@@ -689,9 +725,6 @@ gss_validate(struct rpc_task *task, u32 
 	struct gss_cred *gss_cred = container_of(cred, struct gss_cred,
 						 gc_base);
 	struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred);
-	u32		seq, qop_state;
-	struct iovec	iov;
-	struct xdr_buf verf_buf;
 	struct xdr_netobj mic;
 	u32		flav,len;
 	u32		service;
@@ -705,14 +738,9 @@ gss_validate(struct rpc_task *task, u32 
 	if (flav != RPC_AUTH_GSS)
 		goto out;
 
-	seq = htonl(task->tk_rqstp->rq_seqno);
-	iov.iov_base = &seq;
-	iov.iov_len = sizeof(seq);
-	xdr_buf_from_iov(&iov, &verf_buf);
 	mic.data = (u8 *)p;
 	mic.len = len;
-
-	if (gss_verify_mic(ctx->gc_gss_ctx, &verf_buf, &mic, &qop_state))
+	if (verify_checksum(ctx->gc_gss_ctx, &mic, task->tk_rqstp->rq_seqnos))
 		goto out;
 	service = gss_pseudoflavor_to_service(gss_cred->gc_flavor);
 	switch (service) {
@@ -771,7 +799,7 @@ gss_wrap_req(struct rpc_task *task,
 
 		integ_len = p++;
 		offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base;
-		*p++ = htonl(req->rq_seqno);
+		*p++ = htonl(req->rq_seqnos[0]);
 
 		status = encode(rqstp, p, obj);
 		if (status)
@@ -847,7 +875,7 @@ gss_unwrap_resp(struct rpc_task *task,
 		mic_offset = integ_len + data_offset;
 		if (mic_offset > rcv_buf->len)
 			goto out;
-		if (ntohl(*p++) != req->rq_seqno)
+		if (ntohl(*p++) != req->rq_seqnos[0])
 			goto out;
 
 		if (xdr_buf_subsegment(rcv_buf, &integ_buf, data_offset,
diff -puN net/sunrpc/xprt.c~clnt-remember-more-seqnos net/sunrpc/xprt.c
--- linux-2.5.72/net/sunrpc/xprt.c~clnt-remember-more-seqnos	2003-06-19 18:38:57.000000000 -0400
+++ linux-2.5.72-bfields/net/sunrpc/xprt.c	2003-06-19 18:38:57.000000000 -0400
@@ -1312,6 +1312,7 @@ xprt_request_init(struct rpc_task *task,
 	req->rq_task	= task;
 	req->rq_xprt    = xprt;
 	req->rq_xid     = xprt_alloc_xid();
+	memset(req->rq_seqnos, 0, sizeof(req->rq_seqnos));
 	INIT_LIST_HEAD(&req->rq_list);
 	dprintk("RPC: %4d reserved req %p xid %08x\n", task->tk_pid,
 			req, req->rq_xid);
diff -puN include/linux/sunrpc/xprt.h~clnt-remember-more-seqnos include/linux/sunrpc/xprt.h
--- linux-2.5.72/include/linux/sunrpc/xprt.h~clnt-remember-more-seqnos	2003-06-19 18:38:57.000000000 -0400
+++ linux-2.5.72-bfields/include/linux/sunrpc/xprt.h	2003-06-19 18:38:57.000000000 -0400
@@ -95,7 +95,9 @@ struct rpc_rqst {
 	struct rpc_rqst *	rq_next;	/* free list */
 	int			rq_cong;	/* has incremented xprt->cong */
 	int			rq_received;	/* receive completed */
-	u32			rq_seqno;	/* gss seq no. used on req. */
+#define GSS_SEQNO_CACHE		4
+	u32			rq_seqnos[GSS_SEQNO_CACHE];
+						/* gss seq no.s used on req. */
 
 	struct list_head	rq_list;
 

_