From de4594a51c904ddcd6c3a6cdd100f7c1d94d3239 Mon Sep 17 00:00:00 2001 From: Neil Horman Date: Tue, 20 Nov 2012 10:14:30 +0000 Subject: [PATCH] sctp: send abort chunk when max_retrans exceeded In the event that an association exceeds its max_retrans attempts, we should send an ABORT chunk indicating that we are closing the assocation as a result. Because of the nature of the error, its unlikely to be received, but its a nice clean way to close the association if it does make it through, and it will give anyone watching via tcpdump a clue as to what happened. Change notes: v2) * Removed erroneous changes from sctp_make_violation_parmlen Signed-off-by: Neil Horman CC: Vlad Yasevich CC: "David S. Miller" CC: linux-sctp@vger.kernel.org Acked-by: Vlad Yasevich Signed-off-by: David S. Miller --- include/net/sctp/sm.h | 2 ++ net/sctp/sm_make_chunk.c | 19 +++++++++++++++++++ net/sctp/sm_sideeffect.c | 9 ++++++++- 3 files changed, 29 insertions(+), 1 deletion(-) diff --git a/include/net/sctp/sm.h b/include/net/sctp/sm.h index b5887e1677e..2a82d138470 100644 --- a/include/net/sctp/sm.h +++ b/include/net/sctp/sm.h @@ -234,6 +234,8 @@ struct sctp_chunk *sctp_make_abort_violation(const struct sctp_association *, struct sctp_chunk *sctp_make_violation_paramlen(const struct sctp_association *, const struct sctp_chunk *, struct sctp_paramhdr *); +struct sctp_chunk *sctp_make_violation_max_retrans(const struct sctp_association *, + const struct sctp_chunk *); struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *, const struct sctp_transport *); struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *, diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c index fbe1636309a..e0f01a4e8cd 100644 --- a/net/sctp/sm_make_chunk.c +++ b/net/sctp/sm_make_chunk.c @@ -1090,6 +1090,25 @@ nodata: return retval; } +struct sctp_chunk *sctp_make_violation_max_retrans( + const struct sctp_association *asoc, + const struct sctp_chunk *chunk) +{ + struct sctp_chunk *retval; + static const char error[] = "Association exceeded its max_retans count"; + size_t payload_len = sizeof(error) + sizeof(sctp_errhdr_t); + + retval = sctp_make_abort(asoc, chunk, payload_len); + if (!retval) + goto nodata; + + sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, sizeof(error)); + sctp_addto_chunk(retval, sizeof(error), error); + +nodata: + return retval; +} + /* Make a HEARTBEAT chunk. */ struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc, const struct sctp_transport *transport) diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c index 6eecf7e6338..c0769569b05 100644 --- a/net/sctp/sm_sideeffect.c +++ b/net/sctp/sm_sideeffect.c @@ -577,7 +577,7 @@ static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands, unsigned int error) { struct sctp_ulpevent *event; - + struct sctp_chunk *abort; /* Cancel any partial delivery in progress. */ sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC); @@ -593,6 +593,13 @@ static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands, sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(event)); + if (asoc->overall_error_count >= asoc->max_retrans) { + abort = sctp_make_violation_max_retrans(asoc, chunk); + if (abort) + sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, + SCTP_CHUNK(abort)); + } + sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, SCTP_STATE(SCTP_STATE_CLOSED)); -- 2.20.1