We should get rid of all own SCTP debug printk macros and use the ones
that the kernel offers anyway instead. This makes the code more readable
and conform to the kernel code, and offers all the features of dynamic
debbuging that pr_debug() et al has, such as only turning on/off portions
of debug messages at runtime through debugfs. The runtime cost of having
CONFIG_DYNAMIC_DEBUG enabled, but none of the debug statements printing,
is negligible [1]. If kernel debugging is completly turned off, then these
statements will also compile into "empty" functions.
While we're at it, we also need to change the Kconfig option as it /now/
only refers to the ifdef'ed code portions in outqueue.c that enable further
debugging/tracing of SCTP transaction fields. Also, since SCTP_ASSERT code
was enabled with this Kconfig option and has now been removed, we
transform those code parts into WARNs resp. where appropriate BUG_ONs so
that those bugs can be more easily detected as probably not many people
have SCTP debugging permanently turned on.
To turn on all SCTP debugging, the following steps are needed:
# mount -t debugfs none /sys/kernel/debug
# echo -n 'module sctp +p' > /sys/kernel/debug/dynamic_debug/control
This can be done more fine-grained on a per file, per line basis and others
as described in [2].
[1] https://www.kernel.org/doc/ols/2009/ols2009-pages-39-46.pdf
[2] Documentation/dynamic-debug-howto.txt
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While this currently cannot trigger any NULL pointer dereference in
sctp_seq_dump_local_addrs(), better change the order of commands to
prevent a future bug to happen. Although we first add SCTP_CMD_NEW_ASOC
and then set the SCTP_CMD_INIT_CHOOSE_TRANSPORT, it is okay for now,
since this primitive is only called by sctp_connect() or sctp_sendmsg()
with sctp_assoc_add_peer() set first. However, lets do this precaution
and first set the transport and then add it to the association hashlist
to prevent in future something to possibly triggering this.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When SCTP is done processing a duplicate cookie chunk, it tries
to delete a newly created association. For that, it has to set
the right association for the side-effect processing to work.
However, when it uses the SCTP_CMD_NEW_ASOC command, that performs
more work then really needed (like hashing the associationa and
assigning it an id) and there is no point to do that only to
delete the association as a next step. In fact, it also creates
an impossible condition where an association may be found by
the getsockopt() call, and that association is empty. This
causes a crash in some sctp getsockopts.
The solution is rather simple. We simply use SCTP_CMD_SET_ASOC
command that doesn't have all the overhead and does exactly
what we need.
Reported-by: Karl Heiss <kheiss@gmail.com>
Tested-by: Karl Heiss <kheiss@gmail.com>
CC: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While sctp handling a duplicate COOKIE-ECHO and the action is
'Association restart', sctp_sf_do_dupcook_a() will processing
the unexpected COOKIE-ECHO for peer restart, but it does not set
the association state to SCTP_STATE_ESTABLISHED, so the association
could stuck in SCTP_STATE_SHUTDOWN_PENDING state forever.
This violates the sctp specification:
RFC 4960 5.2.4. Handle a COOKIE ECHO when a TCB Exists
Action
A) In this case, the peer may have restarted. .....
After this, the endpoint shall enter the ESTABLISHED state.
To resolve this problem, adding a SCTP_CMD_NEW_STATE cmd to the
command list before SCTP_CMD_REPLY cmd, this will set the restart
association to SCTP_STATE_ESTABLISHED state properly and also avoid
I-bit being set in the DATA chunk header when COOKIE_ACK is bundled
with DATA chunks.
Signed-off-by: Xufeng Zhang <xufeng.zhang@windriver.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull trivial branch from Jiri Kosina:
"Usual stuff -- comment/printk typo fixes, documentation updates, dead
code elimination."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (39 commits)
HOWTO: fix double words typo
x86 mtrr: fix comment typo in mtrr_bp_init
propagate name change to comments in kernel source
doc: Update the name of profiling based on sysfs
treewide: Fix typos in various drivers
treewide: Fix typos in various Kconfig
wireless: mwifiex: Fix typo in wireless/mwifiex driver
messages: i2o: Fix typo in messages/i2o
scripts/kernel-doc: check that non-void fcts describe their return value
Kernel-doc: Convention: Use a "Return" section to describe return values
radeon: Fix typo and copy/paste error in comments
doc: Remove unnecessary declarations from Documentation/accounting/getdelays.c
various: Fix spelling of "asynchronous" in comments.
Fix misspellings of "whether" in comments.
eisa: Fix spelling of "asynchronous".
various: Fix spelling of "registered" in comments.
doc: fix quite a few typos within Documentation
target: iscsi: fix comment typos in target/iscsi drivers
treewide: fix typo of "suport" in various comments and Kconfig
treewide: fix typo of "suppport" in various comments
...
The current SCTP stack is lacking a mechanism to have per association
statistics. This is an implementation modeled after OpenSolaris'
SCTP_GET_ASSOC_STATS.
Userspace part will follow on lksctp if/when there is a general ACK on
this.
V4:
- Move ipackets++ before q->immediate.func() for consistency reasons
- Move sctp_max_rto() at the end of sctp_transport_update_rto() to avoid
returning bogus RTO values
- return asoc->rto_min when max_obs_rto value has not changed
V3:
- Increase ictrlchunks in sctp_assoc_bh_rcv() as well
- Move ipackets++ to sctp_inq_push()
- return 0 when no rto updates took place since the last call
V2:
- Implement partial retrieval of stat struct to cope for future expansion
- Kill the rtxpackets counter as it cannot be precise anyway
- Rename outseqtsns to outofseqtsns to make it clearer that these are out
of sequence unexpected TSNs
- Move asoc->ipackets++ under a lock to avoid potential miscounts
- Fold asoc->opackets++ into the already existing asoc check
- Kill unneeded (q->asoc) test when increasing rtxchunks
- Do not count octrlchunks if sending failed (SCTP_XMIT_OK != 0)
- Don't count SHUTDOWNs as SACKs
- Move SCTP_GET_ASSOC_STATS to the private space API
- Adjust the len check in sctp_getsockopt_assoc_stats() to allow for
future struct growth
- Move association statistics in their own struct
- Update idupchunks when we send a SACK with dup TSNs
- return min_rto in max_rto when RTO has not changed. Also return the
transport when max_rto last changed.
Signed-off: Michele Baldessari <michele@acksyn.org>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If the variable parameter length provided in the mandatory
heartbeat information parameter exceeds the calculated payload
length the packet has been corrupted. Reply with a parameter
length protocol violation message.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Suppose we have an SCTP connection with two paths. After connection is
established, path1 is not available, thus this path is marked as inactive. Then
traffic goes through path2, but for some reasons packets are delayed (after
rto.max). Because packets are delayed, the retransmit mechanism will switch
again to path1. At this time, we receive a delayed SACK from path2. When we
update the state of the path in sctp_check_transmitted(), we do not take into
account the source address of the SACK, hence we update the wrong path.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add struct net as a parameter to sctp_verify_param so it can be passed
to sctp_verify_ext_param where struct net will be needed when the sctp
tunables become per net tunables.
Add struct net as a parameter to sctp_verify_init so struct net can be
passed to sctp_verify_param.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There are a handle of state machine functions primarily those dealing
with processing INIT packets where there is neither a valid endpoint nor
a valid assoication from which to derive a struct net. Therefore add
struct net * to the parameter list of sctp_state_fn_t and update all of
the state machine functions.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
- Kill sctp_get_ctl_sock, it is useless now.
- Pass struct net where needed so net->sctp.ctl_sock is accessible.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Standardize the net core ratelimited logging functions.
Coalesce formats, align arguments.
Change a printk then vprintk sequence to use printf extension %pV.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use of "unsigned int" is preferred to bare "unsigned" in net tree.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Attempt to reduce the number of IP packets emitted in response to single
SCTP packet (2e3216cd) introduced a complication - if a packet contains
two COOKIE_ECHO chunks and nothing else then SCTP state machine corks the
socket while processing first COOKIE_ECHO and then loses the association
and forgets to uncork the socket. To deal with the issue add new SCTP
command which can be used to set association explictly. Use this new
command when processing second COOKIE_ECHO chunk to restore the context
for SCTP state machine.
Signed-off-by: Max Matveev <makc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With this patch a HEARTBEAT chunk is bundled into the ASCONF-ACK
for ADD IP ADDRESS, confirming the new destination as quickly as
possible.
Signed-off-by: Michio Honda <micchie@sfc.wide.ad.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
When initiating a graceful shutdown while having data chunks
on the retransmission queue with a peer which is in zero
window mode the shutdown is never completed because the
retransmission error count is reset periodically by the
following two rules:
- Do not timeout association while doing zero window probe.
- Reset overall error count when a heartbeat request has
been acknowledged.
The graceful shutdown will wait for all outstanding TSN to
be acknowledged before sending the SHUTDOWN request. This
never happens due to the peer's zero window not acknowledging
the continuously retransmitted data chunks. Although the
error counter is incremented for each failed retransmission,
the receiving of the SACK announcing the zero window clears
the error count again immediately. Also heartbeat requests
continue to be sent periodically. The peer acknowledges these
requests causing the error counter to be reset as well.
This patch changes behaviour to only reset the overall error
counter for the above rules while not in shutdown. After
reaching the maximum number of retransmission attempts, the
T5 shutdown guard timer is scheduled to give the receiver
some additional time to recover. The timer is stopped as soon
as the receiver acknowledges any data.
The issue can be easily reproduced by establishing a sctp
association over the loopback device, constantly queueing
data at the sender while not reading any at the receiver.
Wait for the window to reach zero, then initiate a shutdown
by killing both processes simultaneously. The association
will never be freed and the chunks on the retransmission
queue will be retransmitted indefinitely.
Signed-off-by: Thomas Graf <tgraf@infradead.org>
Acked-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make the case labels the same indent as the switch.
git diff -w shows useless break;s removed after returns
and a comment added to an unnecessary default: break;
because of a dubious gcc warning.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If the peer restart the asoc, we should not only fail any unsent/unacked
data, but also stop the T3-rtx, SACK, T4-rto timers, and teardown ASCONF
queues.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch implement event notification SCTP_SENDER_DRY_EVENT.
SCTP Socket API Extensions:
6.1.9. SCTP_SENDER_DRY_EVENT
When the SCTP stack has no more user data to send or retransmit, this
notification is given to the user. Also, at the time when a user app
subscribes to this event, if there is no data to be sent or
retransmit, the stack will immediately send up this notification.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make heartbeat information in sctp_make_heartbeat() instead
of make it in sctp_sf_heartbeat() directly for common using.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
SCTP does not check whether the source address of COOKIE-ECHO
chunk is the original address of INIT chunk or part of the any
address parameters saved in COOKIE in CLOSED state. So even if
the COOKIE-ECHO chunk is from any address but with correct COOKIE,
the COOKIE-ECHO chunk still be accepted. If the COOKIE is not from
a valid address, the assoc should not be established.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Changed the order of processing SHUTDOWN ACK and COOKIE ACK
refer to section 8.4:Handle "Out of the Blue" Packets.
SHUTDOWN ACK chunk should be processed before processing
"Stale Cookie" ERROR or a COOKIE ACK.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
RFC4960, section 3.3.7 said:
If an endpoint receives an ABORT with a format error or no TCB is
found, it MUST silently discard it.
When an endpoint receives ABORT that parameter value is invalid,
drop it.
Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When an endpoint receives ERROR that parameter value is invalid,
send an ABORT to peer with a Protocol Violation error code.
Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Update the comment about sctp_sf_violation_paramlen() to be
more precise.
Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a list_has_sctp_addr function to simplify loop
Based on a patches by Dan Carpenter and David Miller
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change SCTP_DEBUG_PRINTK and SCTP_DEBUG_PRINTK_IPADDR to
use do { print } while (0) guards.
Add SCTP_DEBUG_PRINTK_CONT to fix errors in log when
lines were continued.
Add #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
Add a missing newline in "Failed bind hash alloc"
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
fix some typos and punctuation in comments
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
The transport last_time_used variable is rather useless.
It was only used when determining if CWND needs to be updated
due to idle transport. However, idle transport detection was
based on a Heartbeat timer and last_time_used was not incremented
when sending Heartbeats. As a result the check for cwnd reduction
was always true. We can get rid of the variable and just base
our cwnd manipulation on the HB timer (like the code comment sais).
We also have to call into the cwnd manipulation function regardless
of whether HBs are enabled or not. That way we will detect idle
transports if the user has disabled Heartbeats.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
The "Invalid Stream Identifier" error has a 16 bit reserved
field at the end, thus making the parameter length be 8 bytes.
We've never supplied that reserved field making wireshark
tag the packet as malformed.
Reported-by: Chris Dischino <cdischino@sonusnet.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
This patch implement the receiver side for SACK-IMMEDIATELY
extension:
Section 4.2. Receiver Side Considerations
On reception of an SCTP packet containing a DATA chunk with the I-bit
set, the receiver SHOULD NOT delay the sending of the corresponding
SACK chunk and SHOULD send it back immediately.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Recent commit 8da645e101
sctp: Get rid of an extra routing lookup when adding a transport
introduced a regression in the connection setup. The behavior was
different between IPv4 and IPv6. IPv4 case ended up working because the
route lookup routing returned a NULL route, which triggered another
route lookup later in the output patch that succeeded. In the IPv6 case,
a valid route was returned for first call, but we could not find a valid
source address at the time since the source addresses were not set on the
association yet. Thus resulted in a hung connection.
The solution is to set the source addresses on the association prior to
adding peers.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since our TSN map is capable of holding at most a 4K chunk gap,
there is no way that during this gap, a stream sequence number
(unsigned short) can wrap such that the new number is smaller
then the next expected one. If such a case is encountered,
this is a protocol violation.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Add-IP feature allows users to delete an active transport. If that
transport has chunks in flight, those chunks need to be moved to another
transport or association may get into unrecoverable state.
Reported-by: Rafael Laufer <rlaufer@cisco.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
SCTP RFC 4960 states that unacknowledged HEARTBEATS count as
errors agains a given transport or endpoint. As such, we
should increment the error counts for only for unacknowledged
HB, otherwise we detect failure too soon. This goes for both
the overall error count and the path error count.
Now, there is a difference in how the detection is done
between the two. The path error detection is done after
the increment, so to detect it properly, we actually need
to exceed the path threshold. The overall error detection
is done _BEFORE_ the increment. Thus to detect the failure,
it's enough for the error count to match the threshold.
This is why all the state functions use '>=' to detect failure,
while path detection uses '>'.
Thanks goes to Chunbo Luo <chunbo.luo@windriver.com> who first
proposed patches to fix this issue and made me re-read the spec
and the code to figure out how this cruft really works.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
The receiver of the HEARTBEAT should respond with a HEARTBEAT ACK
that contains the Heartbeat Information field copied from the
received HEARTBEAT chunk. So the received HEARTBEAT-ACK chunk
must have a length of:
sizeof(sctp_chunkhdr_t) + sizeof(sctp_sender_hb_info_t)
A badly formatted HB-ACK chunk, it is possible that we may access
invalid memory. We should really make sure that the chunk format
is what we expect, before attempting to touch the data.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
If Cumulative TSN Ack field of SHUTDOWN chunk is less than the
Cumulative TSN Ack Point then drop the SHUTDOWN chunk.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Currenlty, sctp breaks up user messages into fragments and
sends each fragment to the lower layer by itself. This means
that for each fragment we go all the way down the stack
and back up. This also discourages bundling of multiple
fragments when they can fit into a sigle packet (ex: due
to user setting a low fragmentation threashold).
We introduce a new command SCTP_CMD_SND_MSG and hand the
whole message down state machine. The state machine and
the side-effect parser will cork the queue, add all chunks
from the message to the queue, and then un-cork the queue
thus causing the chunks to get transmitted.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Daniel Borkmann