The Security Considerations section of RFC 5061 has the following
text:
If an SCTP endpoint that supports this extension receives an INIT
that indicates that the peer supports the ASCONF extension but does
NOT support the [RFC4895] extension, the receiver of such an INIT
MUST send an ABORT in response. Note that an implementation is
allowed to silently discard such an INIT as an option as well, but
under NO circumstance is an implementation allowed to proceed with
the association setup by sending an INIT-ACK in response.
An implementation that receives an INIT-ACK that indicates that the
peer does not support the [RFC4895] extension MUST NOT send the
COOKIE-ECHO to establish the association. Instead, the
implementation MUST discard the INIT-ACK and report to the upper-
layer user that an association cannot be established destroying the
Transmission Control Block (TCB).
Follow the recomendations.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ADD-IP spec has a special case for processing ABORTs:
F4) ... One special consideration is that ABORT
Chunks arriving destined to the IP address being deleted MUST be
ignored (see Section 5.3.1 for further details).
Check if the address we received on is in the DEL state, and if
so, ignore the ABORT.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The processing of the ASCONF chunks has changed a lot in the
spec. New items are:
1. A list of ASCONF-ACK chunks is now cached
2. The source of the packet is used in response.
3. New handling for unexpect ASCONF chunks.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that we support AUTH, discard unauthenticated ASCONF and ASCONF ACK
chunks as mandated in the ADD-IP spec.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When processing an unexpected INIT chunk, we do not need to
do any preservation of the old AUTH parameters. In fact,
doing such preservations will nullify AUTH and allow connection
stealing.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Our treatment of Heartbeats is special in that the inital HB chunk
counts against the error count for the association, where as for
other chunks, only retransmissions or timeouts count against us.
As a result, we had an off-by-1 situation with a number of
Heartbeats we could send.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
In net/sctp/sm_statefuns.c::sctp_sf_abort_violation() we may leak
the storage allocated for 'abort' by returning from the function
without using or freeing it. This happens in case
"sctp_auth_recv_cid(SCTP_CID_ABORT, asoc)" is true and we jump to
the 'discard' label.
Spotted by the Coverity checker.
The simple fix is to simply move the creation of the "abort chunk"
to after the possible jump to the 'discard' label. This way we don't
even have to allocate the memory at all in the problem case.
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Commit d0ce92910b broke several retransmit
cases including fast retransmit. The reason is that we should
only delay by rto while doing retranmists as a result of a timeout.
Retransmit as a result of path mtu discover, fast retransmit, or
other evernts that should trigger immidiate retransmissions got broken.
Also, since rto is doubled prior to marking of packets elegable for
retransmission, we never marked correct chunks anyway.
The fix is provide a reason for a given retransmission so that we
can mark chunks appropriately and to save the old rto value to do
comparisons against.
All regressions tests passed with this code.
Spotted by Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Add SCTP-AUTH API. The API implemented here was
agreed to between implementors at the 9th SCTP Interop.
It will be documented in the next revision of the
SCTP socket API spec.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch implements the receive path needed to process authenticated
chunks. Add ability to process the AUTH chunk and handle edge cases
for authenticated COOKIE-ECHO as well.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement processing for the CHUNKS, RANDOM, and HMAC parameters and
deal with how this parameters are effected by association restarts.
In particular, during unexpeted INIT processing, we need to reply with
parameters from the original INIT chunk. Also, after restart, we need
to update the old association with new peer parameters and change the
association shared keys.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch introduces autotuning to the sctp buffer management code
similar to the TCP. The buffer space can be grown if the advertised
receive window still has room. This might happen if small message
sizes are used, which is common in telecom environmens.
New tunables are introduced that provide limits to buffer growth
and memory pressure is entered if to much buffer spaces is used.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If ADDIP is enabled, when an ASCONF chunk is received with ASCONF
paramter length set to zero, this will cause infinite loop.
By the way, if an malformed ASCONF chunk is received, will cause
processing to access memory without verifying.
This is because of not check the validity of parameters in ASCONF chunk.
This patch fixed this.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
While processing OOTB chunks as well as chunks with an invalid
length of 0, it was possible to SCTP to get wedged inside an
infinite loop because we didn't catch the condition correctly,
or didn't mark the packet for discard correctly.
This work is based on original findings and work by
Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Explicitely discard OOTB chunks, whether the result is a
SHUTDOWN COMPLETE or an ABORT. We need to discard the OOTB
SHUTDOWN ACK to prevent bombing attackes since responsed
MUST NOT be bundled. We also explicietely discard in the
ABORT case since that function is widely used internally.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
When SCTP client received an INIT ACK chunk with missing mandatory
parameter such as "cookie parameter", it will send back a ABORT
with T-bit not set and verification tag is set to 0.
This is because before we accept this INIT ACK chunk, we do not know
the peer's tag. This patch change to reflect vtag when responding to
INIT ACK with missing mandatory parameter.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Currently we abort on the INIT chunk we our backlog is currenlty
exceeded. Delay this about untill COOKIE-ECHO to give the user
time to accept the socket. Also, make sure that we treat
sk_max_backlog of 0 as no connections allowed.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
When multi bundling SHUTDOWN-ACK message is received in ESTAB state,
this will cause "sctp protocol violation state" message print many times.
If SHUTDOWN-ACK is bundled 300 times in one packet, message will be
print 300 times. The same problem also exists when received unexpected
HEARTBEAT-ACK message which is bundled message times.
This patch used net_ratelimit() to suppress error messages print too fast.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
PROTOCOL VIOLATION error cause in ABORT is bad encode when make abort
chunk. When SCTP encode ABORT chunk with PROTOCOL VIOLATION error cause,
it just add the error messages to PROTOCOL VIOLATION error cause, the
rest four bytes(struct sctp_paramhdr) is just add to the chunk, not
change the length of error cause. This cause the ABORT chunk to be a bad
format. The chunk is like this:
ABORT chunk
Chunk type: ABORT (6)
Chunk flags: 0x00
Chunk length: 72 (*1)
Protocol violation cause
Cause code: Protocol violation (0x000d)
Cause length: 62 (*2)
Cause information: 5468652063756D756C61746976652074736E2061636B2062...
Cause padding: 0000
[Needless] 00030010
Chunk Length(*1) = 72 but Cause length(*2) only 62, not include the
extend 4 bytes.
((72 - sizeof(chunk_hdr)) = 68) != (62 +3) / 4 * 4
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
We need to drop the SACK if the peer is attempting to acknowledge
unset data, i.e. the CTSN in the SACK is greater or equal to the
next TSN we will send.
Example:
Endpoint A Endpoint B
<--------------- DATA (TSN=1)
SACK(TSN=1) --------------->
<--------------- DATA (TSN=2)
<--------------- DATA (TSN=3)
<--------------- DATA (TSN=4)
<--------------- DATA (TSN=5)
SACK(TSN=1000) --------------->
<--------------- DATA (TSN=6)
<--------------- DATA (TSN=7)
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
During the INIT/COOKIE-ACK collision cases, it's possible to get
into a situation where the association id is not yet set at the time
of the user event generation. As a result, user events have an
association id set to 0 which will confuse applications.
This happens if we hit case B of duplicate cookie processing.
In the particular example found and provided by Oscar Isaula
<Oscar.Isaula@motorola.com>, flow looks like this:
A B
---- INIT-------> (lost)
<---------INIT------
---- INIT-ACK--->
<------ Cookie ECHO
When the Cookie Echo is received, we end up trying to update the
association that was created on A as a result of the (lost) INIT,
but that association doesn't have the ID set yet.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Spring cleaning time...
There seems to be a lot of places in the network code that have
extra bogus semicolons after conditionals. Most commonly is a
bogus semicolon after: switch() { }
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
As stated in the sctp socket api draft:
sac_info: variable
If the sac_state is SCTP_COMM_LOST and an ABORT chunk was received
for this association, sac_info[] contains the complete ABORT chunk as
defined in the SCTP specification RFC2960 [RFC2960] section 3.3.7.
We now save received ABORT chunks into the sac_info field and pass that
to the user.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
So that it is also an offset from skb->head, reduces its size from 8 to 4 bytes
on 64bit architectures, allowing us to combine the 4 bytes hole left by the
layer headers conversion, reducing struct sk_buff size to 256 bytes, i.e. 4
64byte cachelines, and since the sk_buff slab cache is SLAB_HWCACHE_ALIGN...
:-)
Many calculations that previously required that skb->{transport,network,
mac}_header be first converted to a pointer now can be done directly, being
meaningful as offsets or pointers.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2960bis states (Section 8.3):
D) Request an on-demand HEARTBEAT on a specific destination transport
address of a given association.
The endpoint should increment the respective error counter of the
destination transport address each time a HEARTBEAT is sent to that
address and not acknowledged within one RTO.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Once we reach a point where we exceed the max.path.retrans, strike the
transport before updating the rto. This will force transport switch at
the right time, instead of 1 retransmit too late.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Consider the chunk as Out-of-the-Blue if we don't have
an endpoint. Otherwise discard it as before.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Verify init_tag and a_rwnd mandatory parameters in INIT and
INIT-ACK chunks.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ivan Skytte Jorgensen <isj-sctp@i1.dk>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
... so caller can use ->ipaddr instead of ->ipaddr_h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
both are done in one go since almost always we have result of
the latter immediately passed to the former. Possibly non-obvious
note: sctp_process_param() is endian-agnostic
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Its only use happens on the same host, when it gets quoted back to
us. So we are free to flip to net-endian and avoid extra PITA.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
instances of ->cmp_addr() are fine with switching both arguments
to net-endian; callers other than in sctp_cmp_addr_exact() (both
as ->cmp_addr(...) and direct calls of instances) adjusted;
sctp_cmp_addr_exact() switched to net-endian itself and adjustment
is done in its callers
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Part 1: rename sctp_chunk->source, sctp_sockaddr_entry->a,
sctp_transport->ipaddr and sctp_transport->saddr (to ..._h)
The next patch will reintroduce these fields and keep them as
net-endian mirrors of the original (renamed) ones. Split in
two patches to make sure that we hadn't forgotten any instanes.
Later in the series we'll eliminate uses of host-endian variants
(basically switching users to net-endian counterparts as we
progress through that mess). Then host-endian ones will die.
Other embedded host-endian sctp_addr will be easier to switch
directly, so we leave them alone for now.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
also always get __be16 protocol error; switch to SCTP_PERR()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
argument stored for SCTP_CMD_INIT_FAILED is always __be16
(protocol error). Introduced new field and accessor for
it (SCTP_PERR()); switched to their use (from SCTP_U32() and
.u32)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch cleans up the "nomem" conditions that may occur during the
processing by the state machine functions. In most cases we delay adding
side-effect commands until all memory allocations are done.
Signed-off-by: Vladislav Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
