If SCTP-AUTH is enabled, received AUTH chunk with BAD shared key 
identifier will cause kernel panic.

Test as following:
step1: enabled /proc/sys/net/sctp/auth_enable
step 2:  connect  to SCTP server with auth capable. Association is 
established between endpoints. Then send a AUTH chunk with a bad 
shareid, SCTP server will kernel panic after received that AUTH chunk.

SCTP client                   SCTP server
  INIT         ---------->  
    (with auth capable)
               <----------    INIT-ACK
                              (with auth capable)
  COOKIE-ECHO  ---------->
               <----------    COOKIE-ACK
  AUTH         ---------->


AUTH chunk is like this:
  AUTH chunk
    Chunk type: AUTH (15)
    Chunk flags: 0x00
    Chunk length: 28
    Shared key identifier: 10
    HMAC identifier: SHA-1 (1)
    HMAC: 0000000000000000000000000000000000000000

The assignment of NULL to key can safely be removed, since key_for_each 
(which is just list_for_each_entry under the covers does an initial 
assignment to key anyway).

If the endpoint_shared_keys list is empty, or if the key_id being 
requested does not exist, the function as it currently stands returns 
the actuall list_head (in this case endpoint_shared_keys.  Since that 
list_head isn't surrounded by an actuall data structure, the last 
iteration through list_for_each_entry will do a container_of on key, and 
we wind up returning a bogus pointer, instead of NULL, as we should.

> Neil Horman wrote:
>> On Tue, Jan 22, 2008 at 05:29:20PM +0900, Wei Yongjun wrote:
>>
>> FWIW, Ack from me.  The assignment of NULL to key can safely be 
>> removed, since
>> key_for_each (which is just list_for_each_entry under the covers does 
>> an initial
>> assignment to key anyway).
>> If the endpoint_shared_keys list is empty, or if the key_id being 
>> requested does
>> not exist, the function as it currently stands returns the actuall 
>> list_head (in
>> this case endpoint_shared_keys.  Since that list_head isn't 
>> surrounded by an
>> actuall data structure, the last iteration through 
>> list_for_each_entry will do a
>> container_of on key, and we wind up returning a bogus pointer, 
>> instead of NULL,
>> as we should.  Wei's patch corrects that.
>>
>> Regards
>> Neil
>>
>> Acked-by: Neil Horman <nhorman@tuxdriver.com>
>>
>
> Yep, the patch is correct.
>
> Acked-by: Vlad Yasevich <vladislav.yasevich@hp.com>
>
> -vlad
>
Signed-off-by: NWei Yongjun <yjwei@cn.fujitsu.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Acked-by: NVlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

SCTP-AUTH requires selection of CRYPTO, HMAC and SHA1 since
SHA1 is a MUST requirement for AUTH.  We also support SHA256,
but that's optional, so fix the code to treat it as such.
Signed-off-by: NVlad Yasevich <vladislav.yasevich@hp.com>

In the case where no autheticated chunks were specified, we were still
trying to verify that a given chunk needs authentication and doing so
incorrectly.  Add a check for parameter length to make sure we don't
try to use an empty auth_chunks parameter to verify against.
Signed-off-by: NVlad Yasevich <vladislav.yasevich@hp.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch fixes the errors made in the users of the crypto layer during
the sg_init_table conversion.  It also adds a few conversions that were
missing altogether.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch makes three needlessly global functions static.
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Acked-by: NVlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Most drivers need to set length and offset as well, so may as well fold
those three lines into one.

Add sg_assign_page() for those two locations that only needed to set
the page, where the offset/length is set outside of the function context.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Signed-off-by: NJens Axboe <jens.axboe@oracle.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: NVlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch implements the internals operations of the AUTH, such as
key computation and storage.  It also adds necessary variables to
the SCTP data structures.
Signed-off-by: NVlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>