[SCTP]: Implement sac_info field in SCTP_ASSOC_CHANGE notification.

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>

3 files changed, 57 insertions, 17 deletions

diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c
index 135567493119..0a1a197193a2 100644
--- a/net/sctp/sm_sideeffect.c
+++ b/net/sctp/sm_sideeffect.c
@@ -464,7 +464,7 @@ static void sctp_cmd_init_failed(sctp_cmd_seq_t *commands,
         struct sctp_ulpevent *event;
 
         event = sctp_ulpevent_make_assoc_change(asoc,0, SCTP_CANT_STR_ASSOC,
-                                                (__u16)error, 0, 0,
+                                                (__u16)error, 0, 0, NULL,
                                                 GFP_ATOMIC);
 
         if (event)
@@ -492,8 +492,13 @@ static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands,
         /* Cancel any partial delivery in progress. */
         sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC);
 
-        event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
-                                                (__u16)error, 0, 0,
+        if (event_type == SCTP_EVENT_T_CHUNK && subtype.chunk == SCTP_CID_ABORT)
+                event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
+                                                (__u16)error, 0, 0, chunk,
+                                                GFP_ATOMIC);
+        else
+                event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST,
+                                                (__u16)error, 0, 0, NULL,
                                                 GFP_ATOMIC);
         if (event)
                 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index 438e5dc5c714..e0ec16dd678a 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -186,7 +186,7 @@ sctp_disposition_t sctp_sf_do_4_C(const struct sctp_endpoint *ep,
          * notification is passed to the upper layer.
          */
         ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_SHUTDOWN_COMP,
-                                             0, 0, 0, GFP_ATOMIC);
+                                             0, 0, 0, NULL, GFP_ATOMIC);
         if (ev)
                 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
                                 SCTP_ULPEVENT(ev));
@@ -661,7 +661,7 @@ sctp_disposition_t sctp_sf_do_5_1D_ce(const struct sctp_endpoint *ep,
         ev = sctp_ulpevent_make_assoc_change(new_asoc, 0, SCTP_COMM_UP, 0,
                                              new_asoc->c.sinit_num_ostreams,
                                              new_asoc->c.sinit_max_instreams,
-                                             GFP_ATOMIC);
+                                             NULL, GFP_ATOMIC);
         if (!ev)
                 goto nomem_ev;
 
@@ -790,7 +790,7 @@ sctp_disposition_t sctp_sf_do_5_1E_ca(const struct sctp_endpoint *ep,
         ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_UP,
                                              0, asoc->c.sinit_num_ostreams,
                                              asoc->c.sinit_max_instreams,
-                                             GFP_ATOMIC);
+                                             NULL, GFP_ATOMIC);
 
         if (!ev)
                 goto nomem;
@@ -1625,7 +1625,7 @@ static sctp_disposition_t sctp_sf_do_dupcook_a(const struct sctp_endpoint *ep,
         ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_RESTART, 0,
                                              new_asoc->c.sinit_num_ostreams,
                                              new_asoc->c.sinit_max_instreams,
-                                             GFP_ATOMIC);
+                                             NULL, GFP_ATOMIC);
         if (!ev)
                 goto nomem_ev;
 
@@ -1691,7 +1691,7 @@ static sctp_disposition_t sctp_sf_do_dupcook_b(const struct sctp_endpoint *ep,
         ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_UP, 0,
                                              new_asoc->c.sinit_num_ostreams,
                                              new_asoc->c.sinit_max_instreams,
-                                             GFP_ATOMIC);
+                                             NULL, GFP_ATOMIC);
         if (!ev)
                 goto nomem_ev;
 
@@ -1786,7 +1786,7 @@ static sctp_disposition_t sctp_sf_do_dupcook_d(const struct sctp_endpoint *ep,
                                              SCTP_COMM_UP, 0,
                                              asoc->c.sinit_num_ostreams,
                                              asoc->c.sinit_max_instreams,
-                                             GFP_ATOMIC);
+                                             NULL, GFP_ATOMIC);
                 if (!ev)
                         goto nomem;
 
@@ -3035,7 +3035,7 @@ sctp_disposition_t sctp_sf_do_9_2_final(const struct sctp_endpoint *ep,
          * notification is passed to the upper layer.
          */
         ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_SHUTDOWN_COMP,
-                                             0, 0, 0, GFP_ATOMIC);
+                                             0, 0, 0, NULL, GFP_ATOMIC);
         if (!ev)
                 goto nomem;
 
diff --git a/net/sctp/ulpevent.c b/net/sctp/ulpevent.c
index 2e11bc8d5d35..661ea2dd78ba 100644
--- a/net/sctp/ulpevent.c
+++ b/net/sctp/ulpevent.c
@@ -131,19 +131,54 @@ static inline void sctp_ulpevent_release_owner(struct sctp_ulpevent *event)
 struct sctp_ulpevent  *sctp_ulpevent_make_assoc_change(
         const struct sctp_association *asoc,
         __u16 flags, __u16 state, __u16 error, __u16 outbound,
-        __u16 inbound, gfp_t gfp)
+        __u16 inbound, struct sctp_chunk *chunk, gfp_t gfp)
 {
         struct sctp_ulpevent *event;
         struct sctp_assoc_change *sac;
         struct sk_buff *skb;
 
-        event = sctp_ulpevent_new(sizeof(struct sctp_assoc_change),
+        /* If the lower layer passed in the chunk, it will be
+         * an ABORT, so we need to include it in the sac_info.
+         */
+        if (chunk) {
+                /* sctp_inqu_pop() has allready pulled off the chunk
+                 * header.  We need to put it back temporarily
+                 */
+                skb_push(chunk->skb, sizeof(sctp_chunkhdr_t));
+
+                /* Copy the chunk data to a new skb and reserve enough
+                 * head room to use as notification.
+                 */
+                skb = skb_copy_expand(chunk->skb,
+                                      sizeof(struct sctp_assoc_change), 0, gfp);
+
+                if (!skb)
+                        goto fail;
+
+                /* put back the chunk header now that we have a copy */
+                skb_pull(chunk->skb, sizeof(sctp_chunkhdr_t));
+
+                /* Embed the event fields inside the cloned skb.  */
+                event = sctp_skb2event(skb);
+                sctp_ulpevent_init(event, MSG_NOTIFICATION, skb->truesize);
+
+                /* Include the notification structure */
+                sac = (struct sctp_assoc_change *)
+                        skb_push(skb, sizeof(struct sctp_assoc_change));
+
+                /* Trim the buffer to the right length.  */
+                skb_trim(skb, sizeof(struct sctp_assoc_change) +
+                         ntohs(chunk->chunk_hdr->length));
+        } else {
+                event = sctp_ulpevent_new(sizeof(struct sctp_assoc_change),
                                   MSG_NOTIFICATION, gfp);
-        if (!event)
-                goto fail;
-        skb = sctp_event2skb(event);
-        sac = (struct sctp_assoc_change *)
-                skb_put(skb, sizeof(struct sctp_assoc_change));
+                if (!event)
+                        goto fail;
+
+                skb = sctp_event2skb(event);
+                sac = (struct sctp_assoc_change *) skb_put(skb,
+                                        sizeof(struct sctp_assoc_change));
+        }
 
         /* Socket Extensions for SCTP
          * 5.3.1.1 SCTP_ASSOC_CHANGE