diff options
| author | Nikhil Jha <njha@janestreet.com> | 2025-03-19 13:02:39 -0400 |
|---|---|---|
| committer | Anna Schumaker <anna.schumaker@oracle.com> | 2025-05-19 10:14:29 -0400 |
| commit | 08d6ee6d8a10aef958c2af16bb121070290ed589 (patch) | |
| tree | 8846bf8be74aa11b043ecb429ac851d97e8b2199 /include/linux/sunrpc/xprt.h | |
| parent | a5806cd506af5a7c19bcd596e4708b5c464bfd21 (diff) | |
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 <njha@janestreet.com>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Diffstat (limited to 'include/linux/sunrpc/xprt.h')
| -rw-r--r-- | include/linux/sunrpc/xprt.h | 17 |
1 files changed, 16 insertions, 1 deletions
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, |