]> pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - net/sctp/sm_statefuns.c
[SCTP]: Update ASCONF processing to conform to spec.
[linux-2.6-omap-h63xx.git] / net / sctp / sm_statefuns.c
index f01b408508ff6144b94851f1a67ae09c7a7953d4..a1be9d93f1a8a4fc27812f2296aa5189cb8d118e 100644 (file)
@@ -959,7 +959,7 @@ sctp_disposition_t sctp_sf_sendbeat_8_3(const struct sctp_endpoint *ep,
 {
        struct sctp_transport *transport = (struct sctp_transport *) arg;
 
-       if (asoc->overall_error_count >= asoc->max_retrans) {
+       if (asoc->overall_error_count > asoc->max_retrans) {
                sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
                                SCTP_ERROR(ETIMEDOUT));
                /* CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */
@@ -1146,7 +1146,7 @@ sctp_disposition_t sctp_sf_backbeat_8_3(const struct sctp_endpoint *ep,
        /* Check if the timestamp looks valid.  */
        if (time_after(hbinfo->sent_at, jiffies) ||
            time_after(jiffies, hbinfo->sent_at + max_interval)) {
-               SCTP_DEBUG_PRINTK("%s: HEARTBEAT ACK with invalid timestamp"
+               SCTP_DEBUG_PRINTK("%s: HEARTBEAT ACK with invalid timestamp "
                                  "received for transport: %p\n",
                                   __FUNCTION__, link);
                return SCTP_DISPOSITION_DISCARD;
@@ -1309,26 +1309,6 @@ static void sctp_tietags_populate(struct sctp_association *new_asoc,
        new_asoc->c.initial_tsn         = asoc->c.initial_tsn;
 }
 
-static void sctp_auth_params_populate(struct sctp_association *new_asoc,
-                                   const struct sctp_association *asoc)
-{
-       /* Only perform this if AUTH extension is enabled */
-       if (!sctp_auth_enable)
-               return;
-
-       /* We need to provide the same parameter information as
-        * was in the original INIT.  This means that we need to copy
-        * the HMACS, CHUNKS, and RANDOM parameter from the original
-        * assocaition.
-        */
-       memcpy(new_asoc->c.auth_random, asoc->c.auth_random,
-               sizeof(asoc->c.auth_random));
-       memcpy(new_asoc->c.auth_hmacs, asoc->c.auth_hmacs,
-               sizeof(asoc->c.auth_hmacs));
-       memcpy(new_asoc->c.auth_chunks, asoc->c.auth_chunks,
-               sizeof(asoc->c.auth_chunks));
-}
-
 /*
  * Compare vtag/tietag values to determine unexpected COOKIE-ECHO
  * handling action.
@@ -1486,8 +1466,6 @@ static sctp_disposition_t sctp_sf_do_unexpected_init(
 
        sctp_tietags_populate(new_asoc, asoc);
 
-       sctp_auth_params_populate(new_asoc, asoc);
-
        /* B) "Z" shall respond immediately with an INIT ACK chunk.  */
 
        /* If there are errors need to be reported for unknown parameters,
@@ -2305,7 +2283,7 @@ static sctp_disposition_t sctp_sf_do_5_2_6_stale(const struct sctp_endpoint *ep,
        /* If we've sent any data bundled with COOKIE-ECHO we will need to
         * resend
         */
-       sctp_add_cmd_sf(commands, SCTP_CMD_RETRAN,
+       sctp_add_cmd_sf(commands, SCTP_CMD_T1_RETRAN,
                        SCTP_TRANSPORT(asoc->peer.primary_path));
 
        /* Cast away the const modifier, as we want to just
@@ -3399,6 +3377,15 @@ sctp_disposition_t sctp_sf_do_asconf(const struct sctp_endpoint *ep,
                return sctp_sf_pdiscard(ep, asoc, type, arg, commands);
        }
 
+       /* ADD-IP: Section 4.1.1
+        * This chunk MUST be sent in an authenticated way by using
+        * the mechanism defined in [I-D.ietf-tsvwg-sctp-auth]. If this chunk
+        * is received unauthenticated it MUST be silently discarded as
+        * described in [I-D.ietf-tsvwg-sctp-auth].
+        */
+       if (!sctp_addip_noauth && !chunk->auth)
+               return sctp_sf_discard_chunk(ep, asoc, type, arg, commands);
+
        /* Make sure that the ASCONF ADDIP chunk has a valid length.  */
        if (!sctp_chunk_length_valid(chunk, sizeof(sctp_addip_chunk_t)))
                return sctp_sf_violation_chunklen(ep, asoc, type, arg,
@@ -3415,48 +3402,68 @@ sctp_disposition_t sctp_sf_do_asconf(const struct sctp_endpoint *ep,
 
        /* Verify the ASCONF chunk before processing it. */
        if (!sctp_verify_asconf(asoc,
-           (sctp_paramhdr_t *)((void *)addr_param + length),
-           (void *)chunk->chunk_end,
-           &err_param))
+                           (sctp_paramhdr_t *)((void *)addr_param + length),
+                           (void *)chunk->chunk_end,
+                           &err_param))
                return sctp_sf_violation_paramlen(ep, asoc, type,
-                          (void *)&err_param, commands);
+                                                 (void *)&err_param, commands);
 
-       /* ADDIP 4.2 C1) Compare the value of the serial number to the value
+       /* ADDIP 5.2 E1) Compare the value of the serial number to the value
         * the endpoint stored in a new association variable
         * 'Peer-Serial-Number'.
         */
        if (serial == asoc->peer.addip_serial + 1) {
-               /* ADDIP 4.2 C2) If the value found in the serial number is
-                * equal to the ('Peer-Serial-Number' + 1), the endpoint MUST
-                * do V1-V5.
+               /* If this is the first instance of ASCONF in the packet,
+                * we can clean our old ASCONF-ACKs.
+                */
+               if (!chunk->has_asconf)
+                       sctp_assoc_clean_asconf_ack_cache(asoc);
+
+               /* ADDIP 5.2 E4) When the Sequence Number matches the next one
+                * expected, process the ASCONF as described below and after
+                * processing the ASCONF Chunk, append an ASCONF-ACK Chunk to
+                * the response packet and cache a copy of it (in the event it
+                * later needs to be retransmitted).
+                *
+                * Essentially, do V1-V5.
                 */
                asconf_ack = sctp_process_asconf((struct sctp_association *)
                                                 asoc, chunk);
                if (!asconf_ack)
                        return SCTP_DISPOSITION_NOMEM;
-       } else if (serial == asoc->peer.addip_serial) {
-               /* ADDIP 4.2 C3) If the value found in the serial number is
-                * equal to the value stored in the 'Peer-Serial-Number'
-                * IMPLEMENTATION NOTE: As an optimization a receiver may wish
-                * to save the last ASCONF-ACK for some predetermined period of
-                * time and instead of re-processing the ASCONF (with the same
-                * serial number) it may just re-transmit the ASCONF-ACK.
+       } else if (serial < asoc->peer.addip_serial + 1) {
+               /* ADDIP 5.2 E2)
+                * If the value found in the Sequence Number is less than the
+                * ('Peer- Sequence-Number' + 1), simply skip to the next
+                * ASCONF, and include in the outbound response packet
+                * any previously cached ASCONF-ACK response that was
+                * sent and saved that matches the Sequence Number of the
+                * ASCONF.  Note: It is possible that no cached ASCONF-ACK
+                * Chunk exists.  This will occur when an older ASCONF
+                * arrives out of order.  In such a case, the receiver
+                * should skip the ASCONF Chunk and not include ASCONF-ACK
+                * Chunk for that chunk.
                 */
-               if (asoc->addip_last_asconf_ack)
-                       asconf_ack = asoc->addip_last_asconf_ack;
-               else
+               asconf_ack = sctp_assoc_lookup_asconf_ack(asoc, hdr->serial);
+               if (!asconf_ack)
                        return SCTP_DISPOSITION_DISCARD;
        } else {
-               /* ADDIP 4.2 C4) Otherwise, the ASCONF Chunk is discarded since
+               /* ADDIP 5.2 E5) Otherwise, the ASCONF Chunk is discarded since
                 * it must be either a stale packet or from an attacker.
                 */
                return SCTP_DISPOSITION_DISCARD;
        }
 
-       /* ADDIP 4.2 C5) In both cases C2 and C3 the ASCONF-ACK MUST be sent
-        * back to the source address contained in the IP header of the ASCONF
-        * being responded to.
+       /* ADDIP 5.2 E6)  The destination address of the SCTP packet
+        * containing the ASCONF-ACK Chunks MUST be the source address of
+        * the SCTP packet that held the ASCONF Chunks.
+        *
+        * To do this properly, we'll set the destination address of the chunk
+        * and at the transmit time, will try look up the transport to use.
+        * Since ASCONFs may be bundled, the correct transport may not be
+        * created untill we process the entire packet, thus this workaround.
         */
+       asconf_ack->dest = chunk->source;
        sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(asconf_ack));
 
        return SCTP_DISPOSITION_CONSUME;
@@ -3485,6 +3492,15 @@ sctp_disposition_t sctp_sf_do_asconf_ack(const struct sctp_endpoint *ep,
                return sctp_sf_pdiscard(ep, asoc, type, arg, commands);
        }
 
+       /* ADD-IP, Section 4.1.2:
+        * This chunk MUST be sent in an authenticated way by using
+        * the mechanism defined in [I-D.ietf-tsvwg-sctp-auth]. If this chunk
+        * is received unauthenticated it MUST be silently discarded as
+        * described in [I-D.ietf-tsvwg-sctp-auth].
+        */
+       if (!sctp_addip_noauth && !asconf_ack->auth)
+               return sctp_sf_discard_chunk(ep, asoc, type, arg, commands);
+
        /* Make sure that the ADDIP chunk has a valid length.  */
        if (!sctp_chunk_length_valid(asconf_ack, sizeof(sctp_addip_chunk_t)))
                return sctp_sf_violation_chunklen(ep, asoc, type, arg,
@@ -4064,11 +4080,6 @@ static sctp_disposition_t sctp_sf_abort_violation(
        struct sctp_chunk *chunk =  arg;
        struct sctp_chunk *abort = NULL;
 
-       /* Make the abort chunk. */
-       abort = sctp_make_abort_violation(asoc, chunk, payload, paylen);
-       if (!abort)
-               goto nomem;
-
        /* SCTP-AUTH, Section 6.3:
         *    It should be noted that if the receiver wants to tear
         *    down an association in an authenticated way only, the
@@ -4083,6 +4094,11 @@ static sctp_disposition_t sctp_sf_abort_violation(
        if (sctp_auth_recv_cid(SCTP_CID_ABORT, asoc))
                goto discard;
 
+       /* Make the abort chunk. */
+       abort = sctp_make_abort_violation(asoc, chunk, payload, paylen);
+       if (!abort)
+               goto nomem;
+
        if (asoc) {
                sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort));
                SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS);