From 08d6ee6d8a10aef958c2af16bb121070290ed589 Mon Sep 17 00:00:00 2001 From: Nikhil Jha Date: Wed, 19 Mar 2025 13:02:39 -0400 Subject: sunrpc: implement rfc2203 rpcsec_gss seqnum cache This implements a sequence number cache of the last three (right now hardcoded) sent sequence numbers for a given XID, as suggested by the RFC. From RFC2203 5.3.3.1: "Note that the sequence number algorithm requires that the client increment the sequence number even if it is retrying a request with the same RPC transaction identifier. It is not infrequent for clients to get into a situation where they send two or more attempts and a slow server sends the reply for the first attempt. With RPCSEC_GSS, each request and reply will have a unique sequence number. If the client wishes to improve turn around time on the RPC call, it can cache the RPCSEC_GSS sequence number of each request it sends. Then when it receives a response with a matching RPC transaction identifier, it can compute the checksum of each sequence number in the cache to try to match the checksum in the reply's verifier." Signed-off-by: Nikhil Jha Acked-by: Chuck Lever Signed-off-by: Anna Schumaker --- include/linux/sunrpc/xprt.h | 17 ++++++++++++++++- include/trace/events/rpcgss.h | 4 ++-- include/trace/events/sunrpc.h | 2 +- 3 files changed, 19 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h index 81b952649d35..f46d1fb8f71a 100644 --- a/include/linux/sunrpc/xprt.h +++ b/include/linux/sunrpc/xprt.h @@ -30,6 +30,8 @@ #define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT) #define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd) +#define RPC_GSS_SEQNO_ARRAY_SIZE 3U + enum rpc_display_format_t { RPC_DISPLAY_ADDR = 0, RPC_DISPLAY_PORT, @@ -66,7 +68,8 @@ struct rpc_rqst { struct rpc_cred * rq_cred; /* Bound cred */ __be32 rq_xid; /* request XID */ int rq_cong; /* has incremented xprt->cong */ - u32 rq_seqno; /* gss seq no. used on req. */ + u32 rq_seqnos[RPC_GSS_SEQNO_ARRAY_SIZE]; /* past gss req seq nos. */ + unsigned int rq_seqno_count; /* number of entries in rq_seqnos */ int rq_enc_pages_num; struct page **rq_enc_pages; /* scratch pages for use by gss privacy code */ @@ -119,6 +122,18 @@ struct rpc_rqst { #define rq_svec rq_snd_buf.head #define rq_slen rq_snd_buf.len +static inline int xprt_rqst_add_seqno(struct rpc_rqst *req, u32 seqno) +{ + if (likely(req->rq_seqno_count < RPC_GSS_SEQNO_ARRAY_SIZE)) + req->rq_seqno_count++; + + /* Shift array to make room for the newest element at the beginning */ + memmove(&req->rq_seqnos[1], &req->rq_seqnos[0], + (RPC_GSS_SEQNO_ARRAY_SIZE - 1) * sizeof(req->rq_seqnos[0])); + req->rq_seqnos[0] = seqno; + return 0; +} + /* RPC transport layer security policies */ enum xprtsec_policies { RPC_XPRTSEC_NONE = 0, diff --git a/include/trace/events/rpcgss.h b/include/trace/events/rpcgss.h index b0b6300a0cab..8aeae06cf434 100644 --- a/include/trace/events/rpcgss.h +++ b/include/trace/events/rpcgss.h @@ -409,7 +409,7 @@ TRACE_EVENT(rpcgss_seqno, __entry->task_id = task->tk_pid; __entry->client_id = task->tk_client->cl_clid; __entry->xid = be32_to_cpu(rqst->rq_xid); - __entry->seqno = rqst->rq_seqno; + __entry->seqno = *rqst->rq_seqnos; ), TP_printk(SUNRPC_TRACE_TASK_SPECIFIER " xid=0x%08x seqno=%u", @@ -440,7 +440,7 @@ TRACE_EVENT(rpcgss_need_reencode, __entry->client_id = task->tk_client->cl_clid; __entry->xid = be32_to_cpu(task->tk_rqstp->rq_xid); __entry->seq_xmit = seq_xmit; - __entry->seqno = task->tk_rqstp->rq_seqno; + __entry->seqno = *task->tk_rqstp->rq_seqnos; __entry->ret = ret; ), diff --git a/include/trace/events/sunrpc.h b/include/trace/events/sunrpc.h index 5d331383047b..751af7b024f9 100644 --- a/include/trace/events/sunrpc.h +++ b/include/trace/events/sunrpc.h @@ -1100,7 +1100,7 @@ TRACE_EVENT(xprt_transmit, __entry->client_id = rqst->rq_task->tk_client ? rqst->rq_task->tk_client->cl_clid : -1; __entry->xid = be32_to_cpu(rqst->rq_xid); - __entry->seqno = rqst->rq_seqno; + __entry->seqno = *rqst->rq_seqnos; __entry->status = status; ), -- cgit v1.2.3