When retransmitting due to T3 timeout, retransmit all the
in-flight chunks for the corresponding transport/path, including
chunks sent less then 1 rto ago.
This is the correct behaviour according to rfc4960 section 6.3.3
E3 and
"Note: Any DATA chunks that were sent to the address for which the
T3-rtx timer expired but did not fit in one MTU (rule E3 above)
should be marked for retransmission and sent as soon as cwnd
allows (normally, when a SACK arrives). ".
This fixes problems when more then one path is present and the T3
retransmission of the first chunk that timeouts stops the T3 timer
for the initial active path, leaving all the other in-flight
chunks waiting forever or until a new chunk is transmitted on the
same path and timeouts (and this will happen only if the cwnd
allows sending new chunks, but since cwnd was dropped to MTU by
the timeout => it will wait until the first heartbeat).
Example: 10 packets in flight, sent at 0.1 s intervals on the
primary path. The primary path is down and the first packet
timeouts. The first packet is retransmitted on another path, the
T3 timer for the primary path is stopped and cwnd is set to MTU.
All the other 9 in-flight packets will not be retransmitted
(unless more new packets are sent on the primary path which depend
on cwnd allowing it, and even in this case the 9 packets will be
retransmitted only after a new packet timeouts which even in the
best case would be more then RTO).
This commit reverts d0ce92910b and
also removes the now unused transport->last_rto, introduced in
b6157d8e03.
p.s The problem is not only when multiple paths are there. It
can happen in a single homed environment. If the application
stops sending data, it possible to have a hung association.
Signed-off-by: Andrei Pelinescu-Onciul <andrei@iptel.org>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
This provides safety against negative optlen at the type
level instead of depending upon (sometimes non-trivial)
checks against this sprinkled all over the the place, in
each and every implementation.
Based upon work done by Arjan van de Ven and feedback
from Linus Torvalds.
Signed-off-by: David S. Miller <davem@davemloft.net>
This shrinks the size of struct sctp_association a little.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
This patch introduces a new sysctl option to make IPv4 Address Scoping
configurable <draft-stewart-tsvwg-sctp-ipv4-00.txt>.
In networking environments where DNAT rules in iptables prerouting
chains convert destination IP's to link-local/private IP addresses,
SCTP connections fail to establish as the INIT chunk is dropped by the
kernel due to address scope match failure.
For example to support overlapping IP addresses (same IP address with
different vlan id) a Layer-5 application listens on link local IP's,
and there is a DNAT rule that maps the destination IP to a link local
IP. Such applications never get the SCTP INIT if the address-scoping
draft is strictly followed.
This sysctl configuration allows SCTP to function in such
unconventional networking environments.
Sysctl options:
0 - Disable IPv4 address scoping draft altogether
1 - Enable IPv4 address scoping (default, current behavior)
2 - Enable address scoping but allow IPv4 private addresses in init/init-ack
3 - Enable address scoping but allow IPv4 link local address in init/init-ack
Signed-off-by: Bhaskar Dutta <bhaskar.dutta@globallogic.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
We had a bug that we never stored the user-defined value for
MAXSEG when setting the value on an association. Thus future
PMTU events ended up re-writing the frag point and increasing
it past user limit. Additionally, when setting the option on
the socket/endpoint, we effect all current associations, which
is against spec.
Now, we store the user 'maxseg' value along with the computed
'frag_point'. We inherit 'maxseg' from the socket at association
creation and use it as an upper limit for 'frag_point' when its
set.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
SCTP will delay the last part of a large write due to NAGLE, if that
part is smaller then MTU. Since we are doing large writes, we might
as well send the last portion now instead of waiting untill the next
large write happens. The small portion will be sent as is regardless,
so it's better to not delay it.
This is a result of much discussions with Wei Yongjun <yjwei@cn.fujitsu.com>
and Doug Graham <dgraham@nortel.com>. Many thanks go out to them.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
SCTP has a problem that when small chunks are used, it is possible
to exhaust the receiver buffer without fully closing receive window.
This happens due to all overhead that we have account for with small
messages. To fix this, when receive buffer is exceeded, we'll drop
the window to 0 and save the 'drop' portion. When application starts
reading data and freeing up recevie buffer space, we'll wait until
we've reached the 'drop' window and then add back this 'drop' one
mtu at a time. This worked well in testing and under stress produced
rather even recovery.
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>
If a socket has a lot of association that are in the process of
of being closed/aborted, it is possible for a remote to establish
new associations during the time period that the old ones are shutting
down. If this was a result of a close() call, there will be no socket
and will cause a memory leak. We'll prevent this by setting the
socket state to CLOSING and disallow new associations when in this state.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
This patch removes an unused union definition (sctp_cmsg_data_t)
from include/net/sctp/user.h.
Signed-off-by: Rami Rosen <rosenrami@gmail.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
String literals are constant, and usually, we can also tag the array
of pointers const too, moving it to the .rodata section.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to get the tun driver to account packets, we need to be
able to receive packets with destructors set. To be on the safe
side, I added an skb_orphan call for all protocols by default since
some of them (IP in particular) cannot handle receiving packets
destructors properly.
Now it seems that at least one protocol (CAN) expects to be able
to pass skb->sk through the rx path without getting clobbered.
So this patch attempts to fix this properly by moving the skb_orphan
call to where it's actually needed. In particular, I've added it
to skb_set_owner_[rw] which is what most users of skb->destructor
call.
This is actually an improvement for tun too since it means that
we only give back the amount charged to the socket when the skb
is passed to another socket that will also be charged accordingly.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Oliver Hartkopp <olver@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Prior implementation of the new sctp_connectx() call that returns
an association ID did not work correctly on non-blocking socket.
This is because we could not return both a EINPROGRESS error and
an association id. This is a new implementation that supports this.
Originally from Ivan Skytte Jørgensen <isj-sctp@i1.dk
Signed-off-by: Ivan Skytte Jørgensen <isj-sctp@i1.dk
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
RFC 5061 Section 5.1 ASCONF Chunk Procedures said:
B4) Re-transmit the ASCONF Chunk last sent and if possible choose an
alternate destination address (please refer to [RFC4960],
Section 6.4.1). An endpoint MUST NOT add new parameters to this
chunk; it MUST be the same (including its Sequence Number) as
the last ASCONF sent. An endpoint MAY, however, bundle an
additional ASCONF with new ASCONF parameters with the next
Sequence Number. For details, see Section 5.5.
This patch fix to choose an alternate destination address when
re-transmit the ASCONF chunk, with some dup codes cleanup.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Remove 2 TEST_FRAME hacks that are no longer needed. These allowed
sctp regression tests to compile before, but are no longer needed.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit faee47cdbf
(sctp: Fix the RTO-doubling on idle-link heartbeats)
broke the RTO doubling for data retransmits. If the
heartbeat was sent before the data T3-rtx time, the
the RTO will not double upon the T3-rtx expiration.
Distingish between the operations by passing an argument
to the function.
Additionally, Wei Youngjun pointed out that our treatment
of requested HEARTBEATS and timer HEARTBEATS is the same
wrt resetting congestion window. That needs to be separated,
since user requested HEARTBEATS should not treat the link
as idle.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
During peeloff/accept() sctp needs to save the parent socket state
into the new socket so that any options set on the parent are
inherited by the child socket. This was found when the
parent/listener socket issues SO_BINDTODEVICE, but the
data was misrouted after a route cache flush.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
SCTP incorrectly doubles rto ever time a Hearbeat chunk
is generated. However RFC 4960 states:
On an idle destination address that is allowed to heartbeat, it is
recommended that a HEARTBEAT chunk is sent once per RTO of that
destination address plus the protocol parameter 'HB.interval', with
jittering of +/- 50% of the RTO value, and exponential backoff of the
RTO if the previous HEARTBEAT is unanswered.
Essentially, of if the heartbean is unacknowledged, do we double the RTO.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The sctp crc32c checksum is always generated in little endian.
So, we clean up the code to treat it as little endian and remove
all the __force casts.
Suggested by Herbert Xu.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a new version of my patch, now using a module parameter instead
of a sysctl, so that the option is harder to find. Please note that,
once the module is loaded, it is still possible to change the value of
the parameter in /sys/module/sctp/parameters/, which is useful if you
want to do performance comparisons without rebooting.
Computation of SCTP checksums significantly affects the performance of
SCTP. For example, using two dual-Opteron 246 connected using a Gbe
network, it was not possible to achieve more than ~730 Mbps, compared to
941 Mbps after disabling SCTP checksums.
Unfortunately, SCTP checksum offloading in NICs is not commonly
available (yet).
By default, checksums are still enabled, of course.
Signed-off-by: Lucas Nussbaum <lucas.nussbaum@ens-lyon.fr>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
crc32c algorithm provides a byteswaped result. On little-endian
arches, the result ends up in big-endian/network byte order.
On big-endinan arches, the result ends up in little-endian
order and needs to be byte swapped again. Thus calling cpu_to_le32
gives the right output.
Tested-by: Jukka Taimisto <jukka.taimisto@mail.suomi.net>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement socket option SCTP_GET_ASSOC_NUMBER of the latest ietf socket
extensions API draft.
8.2.5. Get the Current Number of Associations (SCTP_GET_ASSOC_NUMBER)
This option gets the current number of associations that are attached
to a one-to-many style socket. The option value is an uint32_t.
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>
Instead of using one atomic_t per protocol, use a percpu_counter
for "sockets_allocated", to reduce cache line contention on
heavy duty network servers.
Note : We revert commit (248969ae31
net: af_unix can make unix_nr_socks visbile in /proc),
since it is not anymore used after sock_prot_inuse_add() addition
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Using NIPQUAD() with NIPQUAD_FMT, %d.%d.%d.%d or %u.%u.%u.%u
can be replaced with %pI4
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Once an endpoint has reached the SHUTDOWN-RECEIVED state,
it MUST NOT send a SHUTDOWN in response to a ULP request.
The Cumulative TSN Ack of the received SHUTDOWN chunk
MUST be processed.
This patch fix to process Cumulative TSN Ack of the received
SHUTDOWN chunk in SHUTDOWN_RECEIVED state.
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>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The gabs array in the sctp_tsnmap structure is only used
in one place, sctp_make_sack(). As such, carrying the
array around in the sctp_tsnmap and thus directly in
the sctp_association is rather pointless since most
of the time it's just taking up space. Now, let
sctp_make_sack create and populate it and then throw
it away when it's done.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The tsn map currently use is 4K large and is stuck inside
the sctp_association structure making memory references REALLY
expensive. What we really need is at most 4K worth of bits
so the biggest map we would have is 512 bytes. Also, the
map is only really usefull when we have gaps to store and
report. As such, starting with minimal map of say 32 TSNs (bits)
should be enough for normal low-loss operations. We can grow
the map by some multiple of 32 along with some extra room any
time we receive the TSN which would put us outside of the map
boundry. As we close gaps, we can shift the map to rebase
it on the latest TSN we've seen. This saves 4088 bytes per
association just in the map alone along savings from the now
unnecessary structure members.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sctp_is_any() function that is used to check for wildcard addresses
only looks at the address itself to determine the address family.
This function is used in the API to check the address passed in from
the user. If the user simply zerroes out the sockaddr_storage and
pass that in, we'll end up failing. So, let's try harder to determine
the address family by also checking the socket if it's possible.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
sctp_chunks should be put on a diet. This is some of the low hanging
fruit that we can strip out. Changes all the __s8/__u8 flags to
bitfields. Saves 12 bytes per chunk.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Since call to function sctp_sf_abort_violation() need paramter 'arg' with
'struct sctp_chunk' type, it will read the chunk type and chunk length from
the chunk_hdr member of chunk. But call to sctp_sf_violation_paramlen()
always with 'struct sctp_paramhdr' type's parameter, it will be passed to
sctp_sf_abort_violation(). This may cause kernel panic.
sctp_sf_violation_paramlen()
|-- sctp_sf_abort_violation()
|-- sctp_make_abort_violation()
This patch fixed this problem. This patch also fix two place which called
sctp_sf_violation_paramlen() with wrong paramter type.
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>
The ipfragok flag controls whether the packet may be fragmented
either on the local host on beyond. The latter is only valid on
IPv4.
In fact, we never want to do the latter even on IPv4 when PMTU is
enabled. This is because even though we can't fragment packets
within SCTP due to the prtocol's inherent faults, we can still
fragment it at IP layer. By setting the DF bit we will improve
the PMTU process.
RFC 2960 only says that we SHOULD clear the DF bit in this case,
so we're compliant even if we set the DF bit. In fact RFC 4960
no longer has this statement.
Once we make this change, we only need to control the local
fragmentation. There is already a bit in the skb which controls
that, local_df. So this patch sets that instead of using the
ipfragok argument.
The only complication is that there isn't a struct sock object
per transport, so for IPv4 we have to resort to changing the
pmtudisc field for every packet. This should be safe though
as the protocol is single-threaded.
Note that after this patch we can remove ipfragok from the rest
of the stack too.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
sctp_outq_flush() can now become static.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
RFC 4960, Section 11.4. Protection of Non-SCTP-Capable Hosts
When an SCTP stack receives a packet containing multiple control or
DATA chunks and the processing of the packet requires the sending of
multiple chunks in response, the sender of the response chunk(s) MUST
NOT send more than one packet. If bundling is supported, multiple
response chunks that fit into a single packet MAY be bundled together
into one single response packet. If bundling is not supported, then
the sender MUST NOT send more than one response chunk and MUST
discard all other responses. Note that this rule does NOT apply to a
SACK chunk, since a SACK chunk is, in itself, a response to DATA and
a SACK does not require a response of more DATA.
We implement this by not servicing our outqueue until we reach the end
of the packet. This enables maximum bundling. We also identify
'response' chunks and make sure that we only send 1 packet when sending
such chunks.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit e9df2e8fd8 ("[IPV6]: Use
appropriate sock tclass setting for routing lookup.") also changed the
way that ECN capable transports mark this capability in IPv6. As a
result, SCTP was not marking ECN capablity because the traffic class
was never set. This patch brings back the markings for IPv6 traffic.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When we are trying to fast retransmit the lowest outstanding TSN, we
need to restart the T3-RTX timer, so that subsequent timeouts will
correctly tag all the packets necessary for retransmissions.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Tested-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Correctly keep track of Fast Recovery state and do not reduce
congestion window multiple times during sucht state.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Tested-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 7cbca67c07 ("[IPV6]: Support
Source Address Selection API (RFC5014)") introduced NULL dereference
of asoc to sctp_v6_get_saddr in net/sctp/ipv6.c.
Pointed out by Johann Felix Soden <johfel@users.sourceforge.net>.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
The specification of sctp_connectx() has been changed to return
an association id. We've added a new socket option that will
return the association id as the return value from the setsockopt()
call. The library that implements sctp_connectx() interface will
implement both socket options.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Brings delayed_ack socket option set/get into line with the latest ietf
socket extensions API draft, while maintaining backwards compatibility.
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>
Fix 3 warnings about discarding const qualifiers:
net/sctp/ulpevent.c:862: warning: passing argument 1 of 'sctp_event2skb' discards qualifiers from pointer target type
net/sctp/sm_statefuns.c:4393: warning: passing argument 1 of 'SCTP_ASOC' discards qualifiers from pointer target type
net/sctp/socket.c:5874: warning: passing argument 1 of 'cmsg_nxthdr' discards qualifiers from pointer target type
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Andrei Pelinescu-Onciul