[SCTP]: Fix protocol violation when receiving an error lenght INIT-ACK

When receiving an error length INIT-ACK during COOKIE-WAIT,
a 0-vtag ABORT will be responsed. This action violates the
protocol apparently. This patch achieves the following things.
1 If the INIT-ACK contains all the fixed parameters, use init-tag
  recorded from INIT-ACK as vtag.
2 If the INIT-ACK doesn't contain all the fixed parameters,
  just reflect its vtag.

Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/net/sctp/command.h b/include/net/sctp/command.h
index 10ae2da6f93b..35b1e83fb96a 100644
--- a/include/net/sctp/command.h
+++ b/include/net/sctp/command.h
@@ -104,6 +104,7 @@ typedef enum {
         SCTP_CMD_ADAPTATION_IND, /* generate and send adaptation event */
         SCTP_CMD_ASSOC_SHKEY,    /* generate the association shared keys */
         SCTP_CMD_T1_RETRAN,      /* Mark for retransmission after T1 timeout  */
+        SCTP_CMD_UPDATE_INITTAG, /* Update peer inittag */
         SCTP_CMD_LAST
 } sctp_verb_t;