SCTP: Allow ADD_IP to work with AUTH for backward compatibility.

This patch adds a tunable that will allow ADD_IP to work without
AUTH for backward compatibility.  The default value is off since
the default value for ADD_IP is off as well.  People who need
to use ADD-IP with older implementations take risks of connection
hijacking and should consider upgrading or turning this tunable on.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>

1 files changed, 6 insertions, 2 deletions

diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index eaad5c5535a8..013e3d3ab0f1 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -262,10 +262,14 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a
          */
         asoc->peer.sack_needed = 1;
 
-        /* Assume that the peer recongizes ASCONF until reported otherwise
-         * via an ERROR chunk.
+        /* Assume that the peer will tell us if he recognizes ASCONF
+         * as part of INIT exchange.
+         * The sctp_addip_noauth option is there for backward compatibilty
+         * and will revert old behavior.
          */
         asoc->peer.asconf_capable = 0;
+        if (sctp_addip_noauth)
+                asoc->peer.asconf_capable = 1;
 
         /* Create an input queue.  */
         sctp_inq_init(&asoc->base.inqueue);