Re: [PATCH] sctp: Make "Invalid Stream Identifier" ERROR followsSACK when bundling

From: Vlad Yasevich
Date: Fri Jul 27 2012 - 17:22:42 EST


here is an untested prototype of what I was talking about. This should handle multiple data chunks.

-vlad

---
include/net/sctp/command.h | 1 +
net/sctp/sm_sideeffect.c | 22 ++++++++++++++++++++++
net/sctp/sm_statefuns.c | 18 ++++++++++--------
3 files changed, 33 insertions(+), 8 deletions(-)

diff --git a/include/net/sctp/command.h b/include/net/sctp/command.h
index 712b3be..4043445 100644
--- a/include/net/sctp/command.h
+++ b/include/net/sctp/command.h
@@ -110,6 +110,7 @@ typedef enum {
SCTP_CMD_SEND_NEXT_ASCONF, /* Send the next ASCONF after ACK */
SCTP_CMD_PURGE_ASCONF_QUEUE, /* Purge all asconf queues.*/
SCTP_CMD_SET_ASOC, /* Restore association context */
+ SCTP_CMD_GEN_BAD_STREAM, /* Issue an Invalid Stream error */
SCTP_CMD_LAST
} sctp_verb_t;

diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c
index 1ff51c9..c5a1322 100644
--- a/net/sctp/sm_sideeffect.c
+++ b/net/sctp/sm_sideeffect.c
@@ -1036,6 +1036,22 @@ static void sctp_cmd_send_asconf(struct sctp_association *asoc)
}
}

+static void sctp_cmd_make_inv_stream_err(sctp_cmd_seq_t *commands,
+ struct sctp_association *asoc,
+ struct sctp_chunk *chunk,
+ struct sctp_datahdr *data_hdr)
+{
+ struct sctp_chunk *err;
+
+ err = sctp_make_op_error(asoc, chunk, SCTP_ERROR_INV_STRM,
+ &data_hdr->stream,
+ sizeof(data_hdr->stream),
+ sizeof(u16));
+ if (err)
+ sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
+ SCTP_CHUNK(err));
+}
+

/* These three macros allow us to pull the debugging code out of the
* main flow of sctp_do_sm() to keep attention focused on the real
@@ -1700,6 +1716,12 @@ static int sctp_cmd_interpreter(sctp_event_t event_type,
asoc = cmd->obj.asoc;
break;

+ case SCTP_CMD_GEN_BAD_STREAM:
+ sctp_cmd_make_inv_stream_err(commands,
+ asoc, chunk,
+ (struct sctp_datahdr *)cmd->obj.ptr);
+ break;
+
default:
pr_warn("Impossible command: %u, %p\n",
cmd->verb, cmd->obj.ptr);
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index 891f5db..57532e3 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -2972,6 +2972,12 @@ discard_noforce:
if (chunk->end_of_packet)
sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, force);

+ /* Queue the INVALID STREAM error after the SACK if one is needed. */
+ if (SCTP_IERROR_BAD_STREAM == error) {
+ sctp_add_cmd_sf(commands, SCTP_CMD_GEN_BAD_STREAM,
+ SCTP_PTR(chunk->subh.data_hdr));
+ }
+
return SCTP_DISPOSITION_DISCARD;
consume:
return SCTP_DISPOSITION_CONSUME;
@@ -3044,6 +3050,10 @@ sctp_disposition_t sctp_sf_eat_data_fast_4_4(const struct sctp_endpoint *ep,
*/
sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SHUTDOWN, SCTP_NULL());
sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE());
+ if (SCTP_IERROR_BAD_STREAM == error) {
+ sctp_add_cmd_sf(commands, SCTP_CMD_GEN_BAD_STREAM,
+ SCTP_PTR(chunk->subh.data_hdr));
+ }
sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART,
SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN));
}
@@ -6140,14 +6150,6 @@ static int sctp_eat_data(const struct sctp_association *asoc,
if (sid >= asoc->c.sinit_max_instreams) {
/* Mark tsn as received even though we drop it */
sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_TSN, SCTP_U32(tsn));
-
- err = sctp_make_op_error(asoc, chunk, SCTP_ERROR_INV_STRM,
- &data_hdr->stream,
- sizeof(data_hdr->stream),
- sizeof(u16));
- if (err)
- sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
- SCTP_CHUNK(err));
return SCTP_IERROR_BAD_STREAM;
}

-- 1.7.7.6


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