diff options
Diffstat (limited to 'net/sctp/sm_statefuns.c')
| -rw-r--r-- | net/sctp/sm_statefuns.c | 148 |
1 files changed, 114 insertions, 34 deletions
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c index d247ed4..61cbd5a 100644 --- a/net/sctp/sm_statefuns.c +++ b/net/sctp/sm_statefuns.c @@ -143,6 +143,12 @@ static sctp_ierror_t sctp_sf_authenticate(const struct sctp_endpoint *ep, const sctp_subtype_t type, struct sctp_chunk *chunk); +static sctp_disposition_t __sctp_sf_do_9_1_abort(const struct sctp_endpoint *ep, + const struct sctp_association *asoc, + const sctp_subtype_t type, + void *arg, + sctp_cmd_seq_t *commands); + /* Small helper function that checks if the chunk length * is of the appropriate length. The 'required_length' argument * is set to be the size of a specific chunk we are testing. @@ -475,7 +481,6 @@ sctp_disposition_t sctp_sf_do_5_1C_ack(const struct sctp_endpoint *ep, sctp_init_chunk_t *initchunk; struct sctp_chunk *err_chunk; struct sctp_packet *packet; - sctp_error_t error; if (!sctp_vtag_verify(chunk, asoc)) return sctp_sf_pdiscard(ep, asoc, type, arg, commands); @@ -500,8 +505,12 @@ sctp_disposition_t sctp_sf_do_5_1C_ack(const struct sctp_endpoint *ep, (sctp_init_chunk_t *)chunk->chunk_hdr, chunk, &err_chunk)) { + sctp_error_t error = SCTP_ERROR_NO_RESOURCE; + /* This chunk contains fatal error. It is to be discarded. - * Send an ABORT, with causes if there is any. + * Send an ABORT, with causes. If there are no causes, + * then there wasn't enough memory. Just terminate + * the association. */ if (err_chunk) { packet = sctp_abort_pkt_new(ep, asoc, arg, @@ -517,12 +526,7 @@ sctp_disposition_t sctp_sf_do_5_1C_ack(const struct sctp_endpoint *ep, SCTP_PACKET(packet)); SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); error = SCTP_ERROR_INV_PARAM; - } else { - error = SCTP_ERROR_NO_RESOURCE; } - } else { - sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); - error = SCTP_ERROR_INV_PARAM; } /* SCTP-AUTH, Section 6.3: @@ -2073,11 +2077,20 @@ sctp_disposition_t sctp_sf_shutdown_pending_abort( if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t))) return sctp_sf_pdiscard(ep, asoc, type, arg, commands); + /* ADD-IP: Special case for ABORT chunks + * F4) One special consideration is that ABORT Chunks arriving + * destined to the IP address being deleted MUST be + * ignored (see Section 5.3.1 for further details). + */ + if (SCTP_ADDR_DEL == + sctp_bind_addr_state(&asoc->base.bind_addr, &chunk->dest)) + return sctp_sf_discard_chunk(ep, asoc, type, arg, commands); + /* Stop the T5-shutdown guard timer. */ sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); - return sctp_sf_do_9_1_abort(ep, asoc, type, arg, commands); + return __sctp_sf_do_9_1_abort(ep, asoc, type, arg, commands); } /* @@ -2109,6 +2122,15 @@ sctp_disposition_t sctp_sf_shutdown_sent_abort(const struct sctp_endpoint *ep, if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t))) return sctp_sf_pdiscard(ep, asoc, type, arg, commands); + /* ADD-IP: Special case for ABORT chunks + * F4) One special consideration is that ABORT Chunks arriving + * destined to the IP address being deleted MUST be + * ignored (see Section 5.3.1 for further details). + */ + if (SCTP_ADDR_DEL == + sctp_bind_addr_state(&asoc->base.bind_addr, &chunk->dest)) + return sctp_sf_discard_chunk(ep, asoc, type, arg, commands); + /* Stop the T2-shutdown timer. */ sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); @@ -2117,7 +2139,7 @@ sctp_disposition_t sctp_sf_shutdown_sent_abort(const struct sctp_endpoint *ep, sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); - return sctp_sf_do_9_1_abort(ep, asoc, type, arg, commands); + return __sctp_sf_do_9_1_abort(ep, asoc, type, arg, commands); } /* @@ -2344,8 +2366,6 @@ sctp_disposition_t sctp_sf_do_9_1_abort(const struct sctp_endpoint *ep, sctp_cmd_seq_t *commands) { struct sctp_chunk *chunk = arg; - unsigned len; - __be16 error = SCTP_ERROR_NO_ERROR; if (!sctp_vtag_verify_either(chunk, asoc)) return sctp_sf_pdiscard(ep, asoc, type, arg, commands); @@ -2363,6 +2383,28 @@ sctp_disposition_t sctp_sf_do_9_1_abort(const struct sctp_endpoint *ep, if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t))) return sctp_sf_pdiscard(ep, asoc, type, arg, commands); + /* ADD-IP: Special case for ABORT chunks + * F4) One special consideration is that ABORT Chunks arriving + * destined to the IP address being deleted MUST be + * ignored (see Section 5.3.1 for further details). + */ + if (SCTP_ADDR_DEL == + sctp_bind_addr_state(&asoc->base.bind_addr, &chunk->dest)) + return sctp_sf_discard_chunk(ep, asoc, type, arg, commands); + + return __sctp_sf_do_9_1_abort(ep, asoc, type, arg, commands); +} + +static sctp_disposition_t __sctp_sf_do_9_1_abort(const struct sctp_endpoint *ep, + const struct sctp_association *asoc, + const sctp_subtype_t type, + void *arg, + sctp_cmd_seq_t *commands) +{ + struct sctp_chunk *chunk = arg; + unsigned len; + __be16 error = SCTP_ERROR_NO_ERROR; + /* See if we have an error cause code in the chunk. */ len = ntohs(chunk->chunk_hdr->length); if (len >= sizeof(struct sctp_chunkhdr) + sizeof(struct sctp_errhdr)) @@ -3377,6 +3419,15 @@ 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, @@ -3393,48 +3444,68 @@ 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; @@ -3463,6 +3534,15 @@ 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, @@ -5763,7 +5843,7 @@ static int sctp_eat_data(const struct sctp_association *asoc, /* * Also try to renege to limit our memory usage in the event that * we are under memory pressure - * If we can't renege, don't worry about it, the sk_stream_rmem_schedule + * If we can't renege, don't worry about it, the sk_rmem_schedule * in sctp_ulpevent_make_rcvmsg will drop the frame if we grow our * memory usage too much */ |
