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 <nhorman@tuxdriver.com>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: linux-sctp@vger.kernel.org
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Neil Horman 2012-11-20 10:14:30 +00:00 committed by David S. Miller
parent 388dfc2d2d
commit de4594a51c
3 changed files with 29 additions and 1 deletions

View File

@ -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 *,

View File

@ -1090,6 +1090,25 @@ struct sctp_chunk *sctp_make_violation_paramlen(
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)

View File

@ -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));