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-rw-r--r--net/sctp/sm_make_chunk.c2766
1 files changed, 2766 insertions, 0 deletions
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
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+++ b/net/sctp/sm_make_chunk.c
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+/* SCTP kernel reference Implementation
+ * (C) Copyright IBM Corp. 2001, 2004
+ * Copyright (c) 1999-2000 Cisco, Inc.
+ * Copyright (c) 1999-2001 Motorola, Inc.
+ * Copyright (c) 2001-2002 Intel Corp.
+ *
+ * This file is part of the SCTP kernel reference Implementation
+ *
+ * These functions work with the state functions in sctp_sm_statefuns.c
+ * to implement the state operations. These functions implement the
+ * steps which require modifying existing data structures.
+ *
+ * The SCTP reference implementation is free software;
+ * you can redistribute it and/or modify it under the terms of
+ * the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * The SCTP reference implementation is distributed in the hope that it
+ * will be useful, but WITHOUT ANY WARRANTY; without even the implied
+ * ************************
+ * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU CC; see the file COPYING. If not, write to
+ * the Free Software Foundation, 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ *
+ * Please send any bug reports or fixes you make to the
+ * email address(es):
+ * lksctp developers <lksctp-developers@lists.sourceforge.net>
+ *
+ * Or submit a bug report through the following website:
+ * http://www.sf.net/projects/lksctp
+ *
+ * Written or modified by:
+ * La Monte H.P. Yarroll <piggy@acm.org>
+ * Karl Knutson <karl@athena.chicago.il.us>
+ * C. Robin <chris@hundredacre.ac.uk>
+ * Jon Grimm <jgrimm@us.ibm.com>
+ * Xingang Guo <xingang.guo@intel.com>
+ * Dajiang Zhang <dajiang.zhang@nokia.com>
+ * Sridhar Samudrala <sri@us.ibm.com>
+ * Daisy Chang <daisyc@us.ibm.com>
+ * Ardelle Fan <ardelle.fan@intel.com>
+ * Kevin Gao <kevin.gao@intel.com>
+ *
+ * Any bugs reported given to us we will try to fix... any fixes shared will
+ * be incorporated into the next SCTP release.
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/net.h>
+#include <linux/inet.h>
+#include <asm/scatterlist.h>
+#include <linux/crypto.h>
+#include <net/sock.h>
+
+#include <linux/skbuff.h>
+#include <linux/random.h> /* for get_random_bytes */
+#include <net/sctp/sctp.h>
+#include <net/sctp/sm.h>
+
+extern kmem_cache_t *sctp_chunk_cachep;
+
+SCTP_STATIC
+struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
+ __u8 type, __u8 flags, int paylen);
+static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
+ const struct sctp_association *asoc,
+ const struct sctp_chunk *init_chunk,
+ int *cookie_len,
+ const __u8 *raw_addrs, int addrs_len);
+static int sctp_process_param(struct sctp_association *asoc,
+ union sctp_params param,
+ const union sctp_addr *peer_addr,
+ int gfp);
+
+/* What was the inbound interface for this chunk? */
+int sctp_chunk_iif(const struct sctp_chunk *chunk)
+{
+ struct sctp_af *af;
+ int iif = 0;
+
+ af = sctp_get_af_specific(ipver2af(chunk->skb->nh.iph->version));
+ if (af)
+ iif = af->skb_iif(chunk->skb);
+
+ return iif;
+}
+
+/* RFC 2960 3.3.2 Initiation (INIT) (1)
+ *
+ * Note 2: The ECN capable field is reserved for future use of
+ * Explicit Congestion Notification.
+ */
+static const struct sctp_paramhdr ecap_param = {
+ SCTP_PARAM_ECN_CAPABLE,
+ __constant_htons(sizeof(struct sctp_paramhdr)),
+};
+static const struct sctp_paramhdr prsctp_param = {
+ SCTP_PARAM_FWD_TSN_SUPPORT,
+ __constant_htons(sizeof(struct sctp_paramhdr)),
+};
+
+/* A helper to initialize to initialize an op error inside a
+ * provided chunk, as most cause codes will be embedded inside an
+ * abort chunk.
+ */
+void sctp_init_cause(struct sctp_chunk *chunk, __u16 cause_code,
+ const void *payload, size_t paylen)
+{
+ sctp_errhdr_t err;
+ int padlen;
+ __u16 len;
+
+ /* Cause code constants are now defined in network order. */
+ err.cause = cause_code;
+ len = sizeof(sctp_errhdr_t) + paylen;
+ padlen = len % 4;
+ err.length = htons(len);
+ len += padlen;
+ sctp_addto_chunk(chunk, sizeof(sctp_errhdr_t), &err);
+ chunk->subh.err_hdr = sctp_addto_chunk(chunk, paylen, payload);
+}
+
+/* 3.3.2 Initiation (INIT) (1)
+ *
+ * This chunk is used to initiate a SCTP association between two
+ * endpoints. The format of the INIT chunk is shown below:
+ *
+ * 0 1 2 3
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Type = 1 | Chunk Flags | Chunk Length |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Initiate Tag |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Advertised Receiver Window Credit (a_rwnd) |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Number of Outbound Streams | Number of Inbound Streams |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Initial TSN |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * \ \
+ * / Optional/Variable-Length Parameters /
+ * \ \
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ *
+ * The INIT chunk contains the following parameters. Unless otherwise
+ * noted, each parameter MUST only be included once in the INIT chunk.
+ *
+ * Fixed Parameters Status
+ * ----------------------------------------------
+ * Initiate Tag Mandatory
+ * Advertised Receiver Window Credit Mandatory
+ * Number of Outbound Streams Mandatory
+ * Number of Inbound Streams Mandatory
+ * Initial TSN Mandatory
+ *
+ * Variable Parameters Status Type Value
+ * -------------------------------------------------------------
+ * IPv4 Address (Note 1) Optional 5
+ * IPv6 Address (Note 1) Optional 6
+ * Cookie Preservative Optional 9
+ * Reserved for ECN Capable (Note 2) Optional 32768 (0x8000)
+ * Host Name Address (Note 3) Optional 11
+ * Supported Address Types (Note 4) Optional 12
+ */
+struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,
+ const struct sctp_bind_addr *bp,
+ int gfp, int vparam_len)
+{
+ sctp_inithdr_t init;
+ union sctp_params addrs;
+ size_t chunksize;
+ struct sctp_chunk *retval = NULL;
+ int num_types, addrs_len = 0;
+ struct sctp_sock *sp;
+ sctp_supported_addrs_param_t sat;
+ __u16 types[2];
+ sctp_adaption_ind_param_t aiparam;
+
+ /* RFC 2960 3.3.2 Initiation (INIT) (1)
+ *
+ * Note 1: The INIT chunks can contain multiple addresses that
+ * can be IPv4 and/or IPv6 in any combination.
+ */
+ retval = NULL;
+
+ /* Convert the provided bind address list to raw format. */
+ addrs = sctp_bind_addrs_to_raw(bp, &addrs_len, gfp);
+
+ init.init_tag = htonl(asoc->c.my_vtag);
+ init.a_rwnd = htonl(asoc->rwnd);
+ init.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
+ init.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
+ init.initial_tsn = htonl(asoc->c.initial_tsn);
+
+ /* How many address types are needed? */
+ sp = sctp_sk(asoc->base.sk);
+ num_types = sp->pf->supported_addrs(sp, types);
+
+ chunksize = sizeof(init) + addrs_len + SCTP_SAT_LEN(num_types);
+ chunksize += sizeof(ecap_param);
+ if (sctp_prsctp_enable)
+ chunksize += sizeof(prsctp_param);
+ chunksize += sizeof(aiparam);
+ chunksize += vparam_len;
+
+ /* RFC 2960 3.3.2 Initiation (INIT) (1)
+ *
+ * Note 3: An INIT chunk MUST NOT contain more than one Host
+ * Name address parameter. Moreover, the sender of the INIT
+ * MUST NOT combine any other address types with the Host Name
+ * address in the INIT. The receiver of INIT MUST ignore any
+ * other address types if the Host Name address parameter is
+ * present in the received INIT chunk.
+ *
+ * PLEASE DO NOT FIXME [This version does not support Host Name.]
+ */
+
+ retval = sctp_make_chunk(asoc, SCTP_CID_INIT, 0, chunksize);
+ if (!retval)
+ goto nodata;
+
+ retval->subh.init_hdr =
+ sctp_addto_chunk(retval, sizeof(init), &init);
+ retval->param_hdr.v =
+ sctp_addto_chunk(retval, addrs_len, addrs.v);
+
+ /* RFC 2960 3.3.2 Initiation (INIT) (1)
+ *
+ * Note 4: This parameter, when present, specifies all the
+ * address types the sending endpoint can support. The absence
+ * of this parameter indicates that the sending endpoint can
+ * support any address type.
+ */
+ sat.param_hdr.type = SCTP_PARAM_SUPPORTED_ADDRESS_TYPES;
+ sat.param_hdr.length = htons(SCTP_SAT_LEN(num_types));
+ sctp_addto_chunk(retval, sizeof(sat), &sat);
+ sctp_addto_chunk(retval, num_types * sizeof(__u16), &types);
+
+ sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
+ if (sctp_prsctp_enable)
+ sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
+ aiparam.param_hdr.type = SCTP_PARAM_ADAPTION_LAYER_IND;
+ aiparam.param_hdr.length = htons(sizeof(aiparam));
+ aiparam.adaption_ind = htonl(sp->adaption_ind);
+ sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
+nodata:
+ if (addrs.v)
+ kfree(addrs.v);
+ return retval;
+}
+
+struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
+ const struct sctp_chunk *chunk,
+ int gfp, int unkparam_len)
+{
+ sctp_inithdr_t initack;
+ struct sctp_chunk *retval;
+ union sctp_params addrs;
+ int addrs_len;
+ sctp_cookie_param_t *cookie;
+ int cookie_len;
+ size_t chunksize;
+ sctp_adaption_ind_param_t aiparam;
+
+ retval = NULL;
+
+ /* Note: there may be no addresses to embed. */
+ addrs = sctp_bind_addrs_to_raw(&asoc->base.bind_addr, &addrs_len, gfp);
+
+ initack.init_tag = htonl(asoc->c.my_vtag);
+ initack.a_rwnd = htonl(asoc->rwnd);
+ initack.num_outbound_streams = htons(asoc->c.sinit_num_ostreams);
+ initack.num_inbound_streams = htons(asoc->c.sinit_max_instreams);
+ initack.initial_tsn = htonl(asoc->c.initial_tsn);
+
+ /* FIXME: We really ought to build the cookie right
+ * into the packet instead of allocating more fresh memory.
+ */
+ cookie = sctp_pack_cookie(asoc->ep, asoc, chunk, &cookie_len,
+ addrs.v, addrs_len);
+ if (!cookie)
+ goto nomem_cookie;
+
+ /* Calculate the total size of allocation, include the reserved
+ * space for reporting unknown parameters if it is specified.
+ */
+ chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len;
+
+ /* Tell peer that we'll do ECN only if peer advertised such cap. */
+ if (asoc->peer.ecn_capable)
+ chunksize += sizeof(ecap_param);
+
+ /* Tell peer that we'll do PR-SCTP only if peer advertised. */
+ if (asoc->peer.prsctp_capable)
+ chunksize += sizeof(prsctp_param);
+
+ chunksize += sizeof(aiparam);
+
+ /* Now allocate and fill out the chunk. */
+ retval = sctp_make_chunk(asoc, SCTP_CID_INIT_ACK, 0, chunksize);
+ if (!retval)
+ goto nomem_chunk;
+
+ /* Per the advice in RFC 2960 6.4, send this reply to
+ * the source of the INIT packet.
+ */
+ retval->transport = chunk->transport;
+ retval->subh.init_hdr =
+ sctp_addto_chunk(retval, sizeof(initack), &initack);
+ retval->param_hdr.v = sctp_addto_chunk(retval, addrs_len, addrs.v);
+ sctp_addto_chunk(retval, cookie_len, cookie);
+ if (asoc->peer.ecn_capable)
+ sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param);
+ if (asoc->peer.prsctp_capable)
+ sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
+
+ aiparam.param_hdr.type = SCTP_PARAM_ADAPTION_LAYER_IND;
+ aiparam.param_hdr.length = htons(sizeof(aiparam));
+ aiparam.adaption_ind = htonl(sctp_sk(asoc->base.sk)->adaption_ind);
+ sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
+
+ /* We need to remove the const qualifier at this point. */
+ retval->asoc = (struct sctp_association *) asoc;
+
+ /* RFC 2960 6.4 Multi-homed SCTP Endpoints
+ *
+ * An endpoint SHOULD transmit reply chunks (e.g., SACK,
+ * HEARTBEAT ACK, * etc.) to the same destination transport
+ * address from which it received the DATA or control chunk
+ * to which it is replying.
+ *
+ * [INIT ACK back to where the INIT came from.]
+ */
+ if (chunk)
+ retval->transport = chunk->transport;
+
+nomem_chunk:
+ kfree(cookie);
+nomem_cookie:
+ if (addrs.v)
+ kfree(addrs.v);
+ return retval;
+}
+
+/* 3.3.11 Cookie Echo (COOKIE ECHO) (10):
+ *
+ * This chunk is used only during the initialization of an association.
+ * It is sent by the initiator of an association to its peer to complete
+ * the initialization process. This chunk MUST precede any DATA chunk
+ * sent within the association, but MAY be bundled with one or more DATA
+ * chunks in the same packet.
+ *
+ * 0 1 2 3
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Type = 10 |Chunk Flags | Length |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * / Cookie /
+ * \ \
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ * Chunk Flags: 8 bit
+ *
+ * Set to zero on transmit and ignored on receipt.
+ *
+ * Length: 16 bits (unsigned integer)
+ *
+ * Set to the size of the chunk in bytes, including the 4 bytes of
+ * the chunk header and the size of the Cookie.
+ *
+ * Cookie: variable size
+ *
+ * This field must contain the exact cookie received in the
+ * State Cookie parameter from the previous INIT ACK.
+ *
+ * An implementation SHOULD make the cookie as small as possible
+ * to insure interoperability.
+ */
+struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc,
+ const struct sctp_chunk *chunk)
+{
+ struct sctp_chunk *retval;
+ void *cookie;
+ int cookie_len;
+
+ cookie = asoc->peer.cookie;
+ cookie_len = asoc->peer.cookie_len;
+
+ /* Build a cookie echo chunk. */
+ retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ECHO, 0, cookie_len);
+ if (!retval)
+ goto nodata;
+ retval->subh.cookie_hdr =
+ sctp_addto_chunk(retval, cookie_len, cookie);
+
+ /* RFC 2960 6.4 Multi-homed SCTP Endpoints
+ *
+ * An endpoint SHOULD transmit reply chunks (e.g., SACK,
+ * HEARTBEAT ACK, * etc.) to the same destination transport
+ * address from which it * received the DATA or control chunk
+ * to which it is replying.
+ *
+ * [COOKIE ECHO back to where the INIT ACK came from.]
+ */
+ if (chunk)
+ retval->transport = chunk->transport;
+
+nodata:
+ return retval;
+}
+
+/* 3.3.12 Cookie Acknowledgement (COOKIE ACK) (11):
+ *
+ * This chunk is used only during the initialization of an
+ * association. It is used to acknowledge the receipt of a COOKIE
+ * ECHO chunk. This chunk MUST precede any DATA or SACK chunk sent
+ * within the association, but MAY be bundled with one or more DATA
+ * chunks or SACK chunk in the same SCTP packet.
+ *
+ * 0 1 2 3
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Type = 11 |Chunk Flags | Length = 4 |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ * Chunk Flags: 8 bits
+ *
+ * Set to zero on transmit and ignored on receipt.
+ */
+struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc,
+ const struct sctp_chunk *chunk)
+{
+ struct sctp_chunk *retval;
+
+ retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ACK, 0, 0);
+
+ /* RFC 2960 6.4 Multi-homed SCTP Endpoints
+ *
+ * An endpoint SHOULD transmit reply chunks (e.g., SACK,
+ * HEARTBEAT ACK, * etc.) to the same destination transport
+ * address from which it * received the DATA or control chunk
+ * to which it is replying.
+ *
+ * [COOKIE ACK back to where the COOKIE ECHO came from.]
+ */
+ if (retval && chunk)
+ retval->transport = chunk->transport;
+
+ return retval;
+}
+
+/*
+ * Appendix A: Explicit Congestion Notification:
+ * CWR:
+ *
+ * RFC 2481 details a specific bit for a sender to send in the header of
+ * its next outbound TCP segment to indicate to its peer that it has
+ * reduced its congestion window. This is termed the CWR bit. For
+ * SCTP the same indication is made by including the CWR chunk.
+ * This chunk contains one data element, i.e. the TSN number that
+ * was sent in the ECNE chunk. This element represents the lowest
+ * TSN number in the datagram that was originally marked with the
+ * CE bit.
+ *
+ * 0 1 2 3
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Chunk Type=13 | Flags=00000000| Chunk Length = 8 |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Lowest TSN Number |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ * Note: The CWR is considered a Control chunk.
+ */
+struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc,
+ const __u32 lowest_tsn,
+ const struct sctp_chunk *chunk)
+{
+ struct sctp_chunk *retval;
+ sctp_cwrhdr_t cwr;
+
+ cwr.lowest_tsn = htonl(lowest_tsn);
+ retval = sctp_make_chunk(asoc, SCTP_CID_ECN_CWR, 0,
+ sizeof(sctp_cwrhdr_t));
+
+ if (!retval)
+ goto nodata;
+
+ retval->subh.ecn_cwr_hdr =
+ sctp_addto_chunk(retval, sizeof(cwr), &cwr);
+
+ /* RFC 2960 6.4 Multi-homed SCTP Endpoints
+ *
+ * An endpoint SHOULD transmit reply chunks (e.g., SACK,
+ * HEARTBEAT ACK, * etc.) to the same destination transport
+ * address from which it * received the DATA or control chunk
+ * to which it is replying.
+ *
+ * [Report a reduced congestion window back to where the ECNE
+ * came from.]
+ */
+ if (chunk)
+ retval->transport = chunk->transport;
+
+nodata:
+ return retval;
+}
+
+/* Make an ECNE chunk. This is a congestion experienced report. */
+struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc,
+ const __u32 lowest_tsn)
+{
+ struct sctp_chunk *retval;
+ sctp_ecnehdr_t ecne;
+
+ ecne.lowest_tsn = htonl(lowest_tsn);
+ retval = sctp_make_chunk(asoc, SCTP_CID_ECN_ECNE, 0,
+ sizeof(sctp_ecnehdr_t));
+ if (!retval)
+ goto nodata;
+ retval->subh.ecne_hdr =
+ sctp_addto_chunk(retval, sizeof(ecne), &ecne);
+
+nodata:
+ return retval;
+}
+
+/* Make a DATA chunk for the given association from the provided
+ * parameters. However, do not populate the data payload.
+ */
+struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc,
+ const struct sctp_sndrcvinfo *sinfo,
+ int data_len, __u8 flags, __u16 ssn)
+{
+ struct sctp_chunk *retval;
+ struct sctp_datahdr dp;
+ int chunk_len;
+
+ /* We assign the TSN as LATE as possible, not here when
+ * creating the chunk.
+ */
+ dp.tsn = 0;
+ dp.stream = htons(sinfo->sinfo_stream);
+ dp.ppid = sinfo->sinfo_ppid;
+
+ /* Set the flags for an unordered send. */
+ if (sinfo->sinfo_flags & MSG_UNORDERED) {
+ flags |= SCTP_DATA_UNORDERED;
+ dp.ssn = 0;
+ } else
+ dp.ssn = htons(ssn);
+
+ chunk_len = sizeof(dp) + data_len;
+ retval = sctp_make_chunk(asoc, SCTP_CID_DATA, flags, chunk_len);
+ if (!retval)
+ goto nodata;
+
+ retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
+ memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
+
+nodata:
+ return retval;
+}
+
+/* Create a selective ackowledgement (SACK) for the given
+ * association. This reports on which TSN's we've seen to date,
+ * including duplicates and gaps.
+ */
+struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc)
+{
+ struct sctp_chunk *retval;
+ struct sctp_sackhdr sack;
+ int len;
+ __u32 ctsn;
+ __u16 num_gabs, num_dup_tsns;
+ struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
+
+ ctsn = sctp_tsnmap_get_ctsn(map);
+ SCTP_DEBUG_PRINTK("sackCTSNAck sent: 0x%x.\n", ctsn);
+
+ /* How much room is needed in the chunk? */
+ num_gabs = sctp_tsnmap_num_gabs(map);
+ num_dup_tsns = sctp_tsnmap_num_dups(map);
+
+ /* Initialize the SACK header. */
+ sack.cum_tsn_ack = htonl(ctsn);
+ sack.a_rwnd = htonl(asoc->a_rwnd);
+ sack.num_gap_ack_blocks = htons(num_gabs);
+ sack.num_dup_tsns = htons(num_dup_tsns);
+
+ len = sizeof(sack)
+ + sizeof(struct sctp_gap_ack_block) * num_gabs
+ + sizeof(__u32) * num_dup_tsns;
+
+ /* Create the chunk. */
+ retval = sctp_make_chunk(asoc, SCTP_CID_SACK, 0, len);
+ if (!retval)
+ goto nodata;
+
+ /* RFC 2960 6.4 Multi-homed SCTP Endpoints
+ *
+ * An endpoint SHOULD transmit reply chunks (e.g., SACK,
+ * HEARTBEAT ACK, etc.) to the same destination transport
+ * address from which it received the DATA or control chunk to
+ * which it is replying. This rule should also be followed if
+ * the endpoint is bundling DATA chunks together with the
+ * reply chunk.
+ *
+ * However, when acknowledging multiple DATA chunks received
+ * in packets from different source addresses in a single
+ * SACK, the SACK chunk may be transmitted to one of the
+ * destination transport addresses from which the DATA or
+ * control chunks being acknowledged were received.
+ *
+ * [BUG: We do not implement the following paragraph.
+ * Perhaps we should remember the last transport we used for a
+ * SACK and avoid that (if possible) if we have seen any
+ * duplicates. --piggy]
+ *
+ * When a receiver of a duplicate DATA chunk sends a SACK to a
+ * multi- homed endpoint it MAY be beneficial to vary the
+ * destination address and not use the source address of the
+ * DATA chunk. The reason being that receiving a duplicate
+ * from a multi-homed endpoint might indicate that the return
+ * path (as specified in the source address of the DATA chunk)
+ * for the SACK is broken.
+ *
+ * [Send to the address from which we last received a DATA chunk.]
+ */
+ retval->transport = asoc->peer.last_data_from;
+
+ retval->subh.sack_hdr =
+ sctp_addto_chunk(retval, sizeof(sack), &sack);
+
+ /* Add the gap ack block information. */
+ if (num_gabs)
+ sctp_addto_chunk(retval, sizeof(__u32) * num_gabs,
+ sctp_tsnmap_get_gabs(map));
+
+ /* Add the duplicate TSN information. */
+ if (num_dup_tsns)
+ sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns,
+ sctp_tsnmap_get_dups(map));
+
+nodata:
+ return retval;
+}
+
+/* Make a SHUTDOWN chunk. */
+struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
+ const struct sctp_chunk *chunk)
+{
+ struct sctp_chunk *retval;
+ sctp_shutdownhdr_t shut;
+ __u32 ctsn;
+
+ ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
+ shut.cum_tsn_ack = htonl(ctsn);
+
+ retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN, 0,
+ sizeof(sctp_shutdownhdr_t));
+ if (!retval)
+ goto nodata;
+
+ retval->subh.shutdown_hdr =
+ sctp_addto_chunk(retval, sizeof(shut), &shut);
+
+ if (chunk)
+ retval->transport = chunk->transport;
+nodata:
+ return retval;
+}
+
+struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
+ const struct sctp_chunk *chunk)
+{
+ struct sctp_chunk *retval;
+
+ retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0);
+
+ /* RFC 2960 6.4 Multi-homed SCTP Endpoints
+ *
+ * An endpoint SHOULD transmit reply chunks (e.g., SACK,
+ * HEARTBEAT ACK, * etc.) to the same destination transport
+ * address from which it * received the DATA or control chunk
+ * to which it is replying.
+ *
+ * [ACK back to where the SHUTDOWN came from.]
+ */
+ if (retval && chunk)
+ retval->transport = chunk->transport;
+
+ return retval;
+}
+
+struct sctp_chunk *sctp_make_shutdown_complete(
+ const struct sctp_association *asoc,
+ const struct sctp_chunk *chunk)
+{
+ struct sctp_chunk *retval;
+ __u8 flags = 0;
+
+ /* Maybe set the T-bit if we have no association. */
+ flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
+
+ retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags, 0);
+
+ /* RFC 2960 6.4 Multi-homed SCTP Endpoints
+ *
+ * An endpoint SHOULD transmit reply chunks (e.g., SACK,
+ * HEARTBEAT ACK, * etc.) to the same destination transport
+ * address from which it * received the DATA or control chunk
+ * to which it is replying.
+ *
+ * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK
+ * came from.]
+ */
+ if (retval && chunk)
+ retval->transport = chunk->transport;
+
+ return retval;
+}
+
+/* Create an ABORT. Note that we set the T bit if we have no
+ * association.
+ */
+struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
+ const struct sctp_chunk *chunk,
+ const size_t hint)
+{
+ struct sctp_chunk *retval;
+ __u8 flags = 0;
+
+ /* Maybe set the T-bit if we have no association. */
+ flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;
+
+ retval = sctp_make_chunk(asoc, SCTP_CID_ABORT, flags, hint);
+
+ /* RFC 2960 6.4 Multi-homed SCTP Endpoints
+ *
+ * An endpoint SHOULD transmit reply chunks (e.g., SACK,
+ * HEARTBEAT ACK, * etc.) to the same destination transport
+ * address from which it * received the DATA or control chunk
+ * to which it is replying.
+ *
+ * [ABORT back to where the offender came from.]
+ */
+ if (retval && chunk)
+ retval->transport = chunk->transport;
+
+ return retval;
+}
+
+/* Helper to create ABORT with a NO_USER_DATA error. */
+struct sctp_chunk *sctp_make_abort_no_data(
+ const struct sctp_association *asoc,
+ const struct sctp_chunk *chunk, __u32 tsn)
+{
+ struct sctp_chunk *retval;
+ __u32 payload;
+
+ retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t)
+ + sizeof(tsn));
+
+ if (!retval)
+ goto no_mem;
+
+ /* Put the tsn back into network byte order. */
+ payload = htonl(tsn);
+ sctp_init_cause(retval, SCTP_ERROR_NO_DATA, (const void *)&payload,
+ sizeof(payload));
+
+ /* RFC 2960 6.4 Multi-homed SCTP Endpoints
+ *
+ * An endpoint SHOULD transmit reply chunks (e.g., SACK,
+ * HEARTBEAT ACK, * etc.) to the same destination transport
+ * address from which it * received the DATA or control chunk
+ * to which it is replying.
+ *
+ * [ABORT back to where the offender came from.]
+ */
+ if (chunk)
+ retval->transport = chunk->transport;
+
+no_mem:
+ return retval;
+}
+
+/* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */
+struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc,
+ const struct sctp_chunk *chunk,
+ const struct msghdr *msg)
+{
+ struct sctp_chunk *retval;
+ void *payload = NULL, *payoff;
+ size_t paylen = 0;
+ struct iovec *iov = NULL;
+ int iovlen = 0;
+
+ if (msg) {
+ iov = msg->msg_iov;
+ iovlen = msg->msg_iovlen;
+ paylen = get_user_iov_size(iov, iovlen);
+ }
+
+ retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen);
+ if (!retval)
+ goto err_chunk;
+
+ if (paylen) {
+ /* Put the msg_iov together into payload. */
+ payload = kmalloc(paylen, GFP_ATOMIC);
+ if (!payload)
+ goto err_payload;
+ payoff = payload;
+
+ for (; iovlen > 0; --iovlen) {
+ if (copy_from_user(payoff, iov->iov_base,iov->iov_len))
+ goto err_copy;
+ payoff += iov->iov_len;
+ iov++;
+ }
+ }
+
+ sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, payload, paylen);
+
+ if (paylen)
+ kfree(payload);
+
+ return retval;
+
+err_copy:
+ kfree(payload);
+err_payload:
+ sctp_chunk_free(retval);
+ retval = NULL;
+err_chunk:
+ return retval;
+}
+
+/* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */
+struct sctp_chunk *sctp_make_abort_violation(
+ const struct sctp_association *asoc,
+ const struct sctp_chunk *chunk,
+ const __u8 *payload,
+ const size_t paylen)
+{
+ struct sctp_chunk *retval;
+ struct sctp_paramhdr phdr;
+
+ retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen
+ + sizeof(sctp_chunkhdr_t));
+ if (!retval)
+ goto end;
+
+ sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, payload, paylen);
+
+ phdr.type = htons(chunk->chunk_hdr->type);
+ phdr.length = chunk->chunk_hdr->length;
+ sctp_addto_chunk(retval, sizeof(sctp_paramhdr_t), &phdr);
+
+end:
+ return retval;
+}
+
+/* Make a HEARTBEAT chunk. */
+struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
+ const struct sctp_transport *transport,
+ const void *payload, const size_t paylen)
+{
+ struct sctp_chunk *retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT,
+ 0, paylen);
+
+ if (!retval)
+ goto nodata;
+
+ /* Cast away the 'const', as this is just telling the chunk
+ * what transport it belongs to.
+ */
+ retval->transport = (struct sctp_transport *) transport;
+ retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
+
+nodata:
+ return retval;
+}
+
+struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
+ const struct sctp_chunk *chunk,
+ const void *payload, const size_t paylen)
+{
+ struct sctp_chunk *retval;
+
+ retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen);
+ if (!retval)
+ goto nodata;
+
+ retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload);
+
+ /* RFC 2960 6.4 Multi-homed SCTP Endpoints
+ *
+ * An endpoint SHOULD transmit reply chunks (e.g., SACK,
+ * HEARTBEAT ACK, * etc.) to the same destination transport
+ * address from which it * received the DATA or control chunk
+ * to which it is replying.
+ *
+ * [HBACK back to where the HEARTBEAT came from.]
+ */
+ if (chunk)
+ retval->transport = chunk->transport;
+
+nodata:
+ return retval;
+}
+
+/* Create an Operation Error chunk with the specified space reserved.
+ * This routine can be used for containing multiple causes in the chunk.
+ */
+static struct sctp_chunk *sctp_make_op_error_space(
+ const struct sctp_association *asoc,
+ const struct sctp_chunk *chunk,
+ size_t size)
+{
+ struct sctp_chunk *retval;
+
+ retval = sctp_make_chunk(asoc, SCTP_CID_ERROR, 0,
+ sizeof(sctp_errhdr_t) + size);
+ if (!retval)
+ goto nodata;
+
+ /* RFC 2960 6.4 Multi-homed SCTP Endpoints
+ *
+ * An endpoint SHOULD transmit reply chunks (e.g., SACK,
+ * HEARTBEAT ACK, etc.) to the same destination transport
+ * address from which it received the DATA or control chunk
+ * to which it is replying.
+ *
+ */
+ if (chunk)
+ retval->transport = chunk->transport;
+
+nodata:
+ return retval;
+}
+
+/* Create an Operation Error chunk. */
+struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
+ const struct sctp_chunk *chunk,
+ __u16 cause_code, const void *payload,
+ size_t paylen)
+{
+ struct sctp_chunk *retval;
+
+ retval = sctp_make_op_error_space(asoc, chunk, paylen);
+ if (!retval)
+ goto nodata;
+
+ sctp_init_cause(retval, cause_code, payload, paylen);
+
+nodata:
+ return retval;
+}
+
+/********************************************************************
+ * 2nd Level Abstractions
+ ********************************************************************/
+
+/* Turn an skb into a chunk.
+ * FIXME: Eventually move the structure directly inside the skb->cb[].
+ */
+struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
+ const struct sctp_association *asoc,
+ struct sock *sk)
+{
+ struct sctp_chunk *retval;
+
+ retval = kmem_cache_alloc(sctp_chunk_cachep, SLAB_ATOMIC);
+
+ if (!retval)
+ goto nodata;
+ memset(retval, 0, sizeof(struct sctp_chunk));
+
+ if (!sk) {
+ SCTP_DEBUG_PRINTK("chunkifying skb %p w/o an sk\n", skb);
+ }
+
+ retval->skb = skb;
+ retval->asoc = (struct sctp_association *)asoc;
+ retval->resent = 0;
+ retval->has_tsn = 0;
+ retval->has_ssn = 0;
+ retval->rtt_in_progress = 0;
+ retval->sent_at = 0;
+ retval->singleton = 1;
+ retval->end_of_packet = 0;
+ retval->ecn_ce_done = 0;
+ retval->pdiscard = 0;
+
+ /* sctpimpguide-05.txt Section 2.8.2
+ * M1) Each time a new DATA chunk is transmitted
+ * set the 'TSN.Missing.Report' count for that TSN to 0. The
+ * 'TSN.Missing.Report' count will be used to determine missing chunks
+ * and when to fast retransmit.
+ */
+ retval->tsn_missing_report = 0;
+ retval->tsn_gap_acked = 0;
+ retval->fast_retransmit = 0;
+
+ /* If this is a fragmented message, track all fragments
+ * of the message (for SEND_FAILED).
+ */
+ retval->msg = NULL;
+
+ /* Polish the bead hole. */
+ INIT_LIST_HEAD(&retval->transmitted_list);
+ INIT_LIST_HEAD(&retval->frag_list);
+ SCTP_DBG_OBJCNT_INC(chunk);
+ atomic_set(&retval->refcnt, 1);
+
+nodata:
+ return retval;
+}
+
+/* Set chunk->source and dest based on the IP header in chunk->skb. */
+void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src,
+ union sctp_addr *dest)
+{
+ memcpy(&chunk->source, src, sizeof(union sctp_addr));
+ memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
+}
+
+/* Extract the source address from a chunk. */
+const union sctp_addr *sctp_source(const struct sctp_chunk *chunk)
+{
+ /* If we have a known transport, use that. */
+ if (chunk->transport) {
+ return &chunk->transport->ipaddr;
+ } else {
+ /* Otherwise, extract it from the IP header. */
+ return &chunk->source;
+ }
+}
+
+/* Create a new chunk, setting the type and flags headers from the
+ * arguments, reserving enough space for a 'paylen' byte payload.
+ */
+SCTP_STATIC
+struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc,
+ __u8 type, __u8 flags, int paylen)
+{
+ struct sctp_chunk *retval;
+ sctp_chunkhdr_t *chunk_hdr;
+ struct sk_buff *skb;
+ struct sock *sk;
+
+ /* No need to allocate LL here, as this is only a chunk. */
+ skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen),
+ GFP_ATOMIC);
+ if (!skb)
+ goto nodata;
+
+ /* Make room for the chunk header. */
+ chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t));
+ chunk_hdr->type = type;
+ chunk_hdr->flags = flags;
+ chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t));
+
+ sk = asoc ? asoc->base.sk : NULL;
+ retval = sctp_chunkify(skb, asoc, sk);
+ if (!retval) {
+ kfree_skb(skb);
+ goto nodata;
+ }
+
+ retval->chunk_hdr = chunk_hdr;
+ retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr);
+
+ /* Set the skb to the belonging sock for accounting. */
+ skb->sk = sk;
+
+ return retval;
+nodata:
+ return NULL;
+}
+
+
+/* Release the memory occupied by a chunk. */
+static void sctp_chunk_destroy(struct sctp_chunk *chunk)
+{
+ /* Free the chunk skb data and the SCTP_chunk stub itself. */
+ dev_kfree_skb(chunk->skb);
+
+ SCTP_DBG_OBJCNT_DEC(chunk);
+ kmem_cache_free(sctp_chunk_cachep, chunk);
+}
+
+/* Possibly, free the chunk. */
+void sctp_chunk_free(struct sctp_chunk *chunk)
+{
+ /* Make sure that we are not on any list. */
+ skb_unlink((struct sk_buff *) chunk);
+ list_del_init(&chunk->transmitted_list);
+
+ /* Release our reference on the message tracker. */
+ if (chunk->msg)
+ sctp_datamsg_put(chunk->msg);
+
+ sctp_chunk_put(chunk);
+}
+
+/* Grab a reference to the chunk. */
+void sctp_chunk_hold(struct sctp_chunk *ch)
+{
+ atomic_inc(&ch->refcnt);
+}
+
+/* Release a reference to the chunk. */
+void sctp_chunk_put(struct sctp_chunk *ch)
+{
+ if (atomic_dec_and_test(&ch->refcnt))
+ sctp_chunk_destroy(ch);
+}
+
+/* Append bytes to the end of a chunk. Will panic if chunk is not big
+ * enough.
+ */
+void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data)
+{
+ void *target;
+ void *padding;
+ int chunklen = ntohs(chunk->chunk_hdr->length);
+ int padlen = chunklen % 4;
+
+ padding = skb_put(chunk->skb, padlen);
+ target = skb_put(chunk->skb, len);
+
+ memset(padding, 0, padlen);
+ memcpy(target, data, len);
+
+ /* Adjust the chunk length field. */
+ chunk->chunk_hdr->length = htons(chunklen + padlen + len);
+ chunk->chunk_end = chunk->skb->tail;
+
+ return target;
+}
+
+/* Append bytes from user space to the end of a chunk. Will panic if
+ * chunk is not big enough.
+ * Returns a kernel err value.
+ */
+int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len,
+ struct iovec *data)
+{
+ __u8 *target;
+ int err = 0;
+
+ /* Make room in chunk for data. */
+ target = skb_put(chunk->skb, len);
+
+ /* Copy data (whole iovec) into chunk */
+ if ((err = memcpy_fromiovecend(target, data, off, len)))
+ goto out;
+
+ /* Adjust the chunk length field. */
+ chunk->chunk_hdr->length =
+ htons(ntohs(chunk->chunk_hdr->length) + len);
+ chunk->chunk_end = chunk->skb->tail;
+
+out:
+ return err;
+}
+
+/* Helper function to assign a TSN if needed. This assumes that both
+ * the data_hdr and association have already been assigned.
+ */
+void sctp_chunk_assign_ssn(struct sctp_chunk *chunk)
+{
+ __u16 ssn;
+ __u16 sid;
+
+ if (chunk->has_ssn)
+ return;
+
+ /* This is the last possible instant to assign a SSN. */
+ if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
+ ssn = 0;
+ } else {
+ sid = htons(chunk->subh.data_hdr->stream);
+ if (chunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
+ ssn = sctp_ssn_next(&chunk->asoc->ssnmap->out, sid);
+ else
+ ssn = sctp_ssn_peek(&chunk->asoc->ssnmap->out, sid);
+ ssn = htons(ssn);
+ }
+
+ chunk->subh.data_hdr->ssn = ssn;
+ chunk->has_ssn = 1;
+}
+
+/* Helper function to assign a TSN if needed. This assumes that both
+ * the data_hdr and association have already been assigned.
+ */
+void sctp_chunk_assign_tsn(struct sctp_chunk *chunk)
+{
+ if (!chunk->has_tsn) {
+ /* This is the last possible instant to
+ * assign a TSN.
+ */
+ chunk->subh.data_hdr->tsn =
+ htonl(sctp_association_get_next_tsn(chunk->asoc));
+ chunk->has_tsn = 1;
+ }
+}
+
+/* Create a CLOSED association to use with an incoming packet. */
+struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep,
+ struct sctp_chunk *chunk, int gfp)
+{
+ struct sctp_association *asoc;
+ struct sk_buff *skb;
+ sctp_scope_t scope;
+ struct sctp_af *af;
+
+ /* Create the bare association. */
+ scope = sctp_scope(sctp_source(chunk));
+ asoc = sctp_association_new(ep, ep->base.sk, scope, gfp);
+ if (!asoc)
+ goto nodata;
+ asoc->temp = 1;
+ skb = chunk->skb;
+ /* Create an entry for the source address of the packet. */
+ af = sctp_get_af_specific(ipver2af(skb->nh.iph->version));
+ if (unlikely(!af))
+ goto fail;
+ af->from_skb(&asoc->c.peer_addr, skb, 1);
+nodata:
+ return asoc;
+
+fail:
+ sctp_association_free(asoc);
+ return NULL;
+}
+
+/* Build a cookie representing asoc.
+ * This INCLUDES the param header needed to put the cookie in the INIT ACK.
+ */
+static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
+ const struct sctp_association *asoc,
+ const struct sctp_chunk *init_chunk,
+ int *cookie_len,
+ const __u8 *raw_addrs, int addrs_len)
+{
+ sctp_cookie_param_t *retval;
+ struct sctp_signed_cookie *cookie;
+ struct scatterlist sg;
+ int headersize, bodysize;
+ unsigned int keylen;
+ char *key;
+
+ headersize = sizeof(sctp_paramhdr_t) + SCTP_SECRET_SIZE;
+ bodysize = sizeof(struct sctp_cookie)
+ + ntohs(init_chunk->chunk_hdr->length) + addrs_len;
+
+ /* Pad out the cookie to a multiple to make the signature
+ * functions simpler to write.
+ */
+ if (bodysize % SCTP_COOKIE_MULTIPLE)
+ bodysize += SCTP_COOKIE_MULTIPLE
+ - (bodysize % SCTP_COOKIE_MULTIPLE);
+ *cookie_len = headersize + bodysize;
+
+ retval = (sctp_cookie_param_t *)kmalloc(*cookie_len, GFP_ATOMIC);
+
+ if (!retval) {
+ *cookie_len = 0;
+ goto nodata;
+ }
+
+ /* Clear this memory since we are sending this data structure
+ * out on the network.
+ */
+ memset(retval, 0x00, *cookie_len);
+ cookie = (struct sctp_signed_cookie *) retval->body;
+
+ /* Set up the parameter header. */
+ retval->p.type = SCTP_PARAM_STATE_COOKIE;
+ retval->p.length = htons(*cookie_len);
+
+ /* Copy the cookie part of the association itself. */
+ cookie->c = asoc->c;
+ /* Save the raw address list length in the cookie. */
+ cookie->c.raw_addr_list_len = addrs_len;
+
+ /* Remember PR-SCTP capability. */
+ cookie->c.prsctp_capable = asoc->peer.prsctp_capable;
+
+ /* Save adaption indication in the cookie. */
+ cookie->c.adaption_ind = asoc->peer.adaption_ind;
+
+ /* Set an expiration time for the cookie. */
+ do_gettimeofday(&cookie->c.expiration);
+ TIMEVAL_ADD(asoc->cookie_life, cookie->c.expiration);
+
+ /* Copy the peer's init packet. */
+ memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
+ ntohs(init_chunk->chunk_hdr->length));
+
+ /* Copy the raw local address list of the association. */
+ memcpy((__u8 *)&cookie->c.peer_init[0] +
+ ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len);
+
+ if (sctp_sk(ep->base.sk)->hmac) {
+ /* Sign the message. */
+ sg.page = virt_to_page(&cookie->c);
+ sg.offset = (unsigned long)(&cookie->c) % PAGE_SIZE;
+ sg.length = bodysize;
+ keylen = SCTP_SECRET_SIZE;
+ key = (char *)ep->secret_key[ep->current_key];
+
+ sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen,
+ &sg, 1, cookie->signature);
+ }
+
+nodata:
+ return retval;
+}
+
+/* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */
+struct sctp_association *sctp_unpack_cookie(
+ const struct sctp_endpoint *ep,
+ const struct sctp_association *asoc,
+ struct sctp_chunk *chunk, int gfp,
+ int *error, struct sctp_chunk **errp)
+{
+ struct sctp_association *retval = NULL;
+ struct sctp_signed_cookie *cookie;
+ struct sctp_cookie *bear_cookie;
+ int headersize, bodysize, fixed_size;
+ __u8 digest[SCTP_SIGNATURE_SIZE];
+ struct scatterlist sg;
+ unsigned int keylen, len;
+ char *key;
+ sctp_scope_t scope;
+ struct sk_buff *skb = chunk->skb;
+
+ headersize = sizeof(sctp_chunkhdr_t) + SCTP_SECRET_SIZE;
+ bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
+ fixed_size = headersize + sizeof(struct sctp_cookie);
+
+ /* Verify that the chunk looks like it even has a cookie.
+ * There must be enough room for our cookie and our peer's
+ * INIT chunk.
+ */
+ len = ntohs(chunk->chunk_hdr->length);
+ if (len < fixed_size + sizeof(struct sctp_chunkhdr))
+ goto malformed;
+
+ /* Verify that the cookie has been padded out. */
+ if (bodysize % SCTP_COOKIE_MULTIPLE)
+ goto malformed;
+
+ /* Process the cookie. */
+ cookie = chunk->subh.cookie_hdr;
+ bear_cookie = &cookie->c;
+
+ if (!sctp_sk(ep->base.sk)->hmac)
+ goto no_hmac;
+
+ /* Check the signature. */
+ keylen = SCTP_SECRET_SIZE;
+ sg.page = virt_to_page(bear_cookie);
+ sg.offset = (unsigned long)(bear_cookie) % PAGE_SIZE;
+ sg.length = bodysize;
+ key = (char *)ep->secret_key[ep->current_key];
+
+ memset(digest, 0x00, sizeof(digest));
+ sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen, &sg,
+ 1, digest);
+
+ if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
+ /* Try the previous key. */
+ key = (char *)ep->secret_key[ep->last_key];
+ memset(digest, 0x00, sizeof(digest));
+ sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen,
+ &sg, 1, digest);
+
+ if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
+ /* Yikes! Still bad signature! */
+ *error = -SCTP_IERROR_BAD_SIG;
+ goto fail;
+ }
+ }
+
+no_hmac:
+ /* IG Section 2.35.2:
+ * 3) Compare the port numbers and the verification tag contained
+ * within the COOKIE ECHO chunk to the actual port numbers and the
+ * verification tag within the SCTP common header of the received
+ * packet. If these values do not match the packet MUST be silently
+ * discarded,
+ */
+ if (ntohl(chunk->sctp_hdr->vtag) != bear_cookie->my_vtag) {
+ *error = -SCTP_IERROR_BAD_TAG;
+ goto fail;
+ }
+
+ if (ntohs(chunk->sctp_hdr->source) != bear_cookie->peer_addr.v4.sin_port ||
+ ntohs(chunk->sctp_hdr->dest) != bear_cookie->my_port) {
+ *error = -SCTP_IERROR_BAD_PORTS;
+ goto fail;
+ }
+
+ /* Check to see if the cookie is stale. If there is already
+ * an association, there is no need to check cookie's expiration
+ * for init collision case of lost COOKIE ACK.
+ */
+ if (!asoc && tv_lt(bear_cookie->expiration, skb->stamp)) {
+ __u16 len;
+ /*
+ * Section 3.3.10.3 Stale Cookie Error (3)
+ *
+ * Cause of error
+ * ---------------
+ * Stale Cookie Error: Indicates the receipt of a valid State
+ * Cookie that has expired.
+ */
+ len = ntohs(chunk->chunk_hdr->length);
+ *errp = sctp_make_op_error_space(asoc, chunk, len);
+ if (*errp) {
+ suseconds_t usecs = (skb->stamp.tv_sec -
+ bear_cookie->expiration.tv_sec) * 1000000L +
+ skb->stamp.tv_usec -
+ bear_cookie->expiration.tv_usec;
+
+ usecs = htonl(usecs);
+ sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
+ &usecs, sizeof(usecs));
+ *error = -SCTP_IERROR_STALE_COOKIE;
+ } else
+ *error = -SCTP_IERROR_NOMEM;
+
+ goto fail;
+ }
+
+ /* Make a new base association. */
+ scope = sctp_scope(sctp_source(chunk));
+ retval = sctp_association_new(ep, ep->base.sk, scope, gfp);
+ if (!retval) {
+ *error = -SCTP_IERROR_NOMEM;
+ goto fail;
+ }
+
+ /* Set up our peer's port number. */
+ retval->peer.port = ntohs(chunk->sctp_hdr->source);
+
+ /* Populate the association from the cookie. */
+ memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie));
+
+ if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie,
+ GFP_ATOMIC) < 0) {
+ *error = -SCTP_IERROR_NOMEM;
+ goto fail;
+ }
+
+ /* Also, add the destination address. */
+ if (list_empty(&retval->base.bind_addr.address_list)) {
+ sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest,
+ GFP_ATOMIC);
+ }
+
+ retval->next_tsn = retval->c.initial_tsn;
+ retval->ctsn_ack_point = retval->next_tsn - 1;
+ retval->addip_serial = retval->c.initial_tsn;
+ retval->adv_peer_ack_point = retval->ctsn_ack_point;
+ retval->peer.prsctp_capable = retval->c.prsctp_capable;
+ retval->peer.adaption_ind = retval->c.adaption_ind;
+
+ /* The INIT stuff will be done by the side effects. */
+ return retval;
+
+fail:
+ if (retval)
+ sctp_association_free(retval);
+
+ return NULL;
+
+malformed:
+ /* Yikes! The packet is either corrupt or deliberately
+ * malformed.
+ */
+ *error = -SCTP_IERROR_MALFORMED;
+ goto fail;
+}
+
+/********************************************************************
+ * 3rd Level Abstractions
+ ********************************************************************/
+
+struct __sctp_missing {
+ __u32 num_missing;
+ __u16 type;
+} __attribute__((packed));
+
+/*
+ * Report a missing mandatory parameter.
+ */
+static int sctp_process_missing_param(const struct sctp_association *asoc,
+ sctp_param_t paramtype,
+ struct sctp_chunk *chunk,
+ struct sctp_chunk **errp)
+{
+ struct __sctp_missing report;
+ __u16 len;
+
+ len = WORD_ROUND(sizeof(report));
+
+ /* Make an ERROR chunk, preparing enough room for
+ * returning multiple unknown parameters.
+ */
+ if (!*errp)
+ *errp = sctp_make_op_error_space(asoc, chunk, len);
+
+ if (*errp) {
+ report.num_missing = htonl(1);
+ report.type = paramtype;
+ sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM,
+ &report, sizeof(report));
+ }
+
+ /* Stop processing this chunk. */
+ return 0;
+}
+
+/* Report an Invalid Mandatory Parameter. */
+static int sctp_process_inv_mandatory(const struct sctp_association *asoc,
+ struct sctp_chunk *chunk,
+ struct sctp_chunk **errp)
+{
+ /* Invalid Mandatory Parameter Error has no payload. */
+
+ if (!*errp)
+ *errp = sctp_make_op_error_space(asoc, chunk, 0);
+
+ if (*errp)
+ sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, NULL, 0);
+
+ /* Stop processing this chunk. */
+ return 0;
+}
+
+static int sctp_process_inv_paramlength(const struct sctp_association *asoc,
+ struct sctp_paramhdr *param,
+ const struct sctp_chunk *chunk,
+ struct sctp_chunk **errp)
+{
+ char error[] = "The following parameter had invalid length:";
+ size_t payload_len = WORD_ROUND(sizeof(error)) +
+ sizeof(sctp_paramhdr_t);
+
+
+ /* Create an error chunk and fill it in with our payload. */
+ if (!*errp)
+ *errp = sctp_make_op_error_space(asoc, chunk, payload_len);
+
+ if (*errp) {
+ sctp_init_cause(*errp, SCTP_ERROR_PROTO_VIOLATION, error,
+ sizeof(error));
+ sctp_addto_chunk(*errp, sizeof(sctp_paramhdr_t), param);
+ }
+
+ return 0;
+}
+
+
+/* Do not attempt to handle the HOST_NAME parm. However, do
+ * send back an indicator to the peer.
+ */
+static int sctp_process_hn_param(const struct sctp_association *asoc,
+ union sctp_params param,
+ struct sctp_chunk *chunk,
+ struct sctp_chunk **errp)
+{
+ __u16 len = ntohs(param.p->length);
+
+ /* Make an ERROR chunk. */
+ if (!*errp)
+ *errp = sctp_make_op_error_space(asoc, chunk, len);
+
+ if (*errp)
+ sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED,
+ param.v, len);
+
+ /* Stop processing this chunk. */
+ return 0;
+}
+
+/* RFC 3.2.1 & the Implementers Guide 2.2.
+ *
+ * The Parameter Types are encoded such that the
+ * highest-order two bits specify the action that must be
+ * taken if the processing endpoint does not recognize the
+ * Parameter Type.
+ *
+ * 00 - Stop processing this SCTP chunk and discard it,
+ * do not process any further chunks within it.
+ *
+ * 01 - Stop processing this SCTP chunk and discard it,
+ * do not process any further chunks within it, and report
+ * the unrecognized parameter in an 'Unrecognized
+ * Parameter Type' (in either an ERROR or in the INIT ACK).
+ *
+ * 10 - Skip this parameter and continue processing.
+ *
+ * 11 - Skip this parameter and continue processing but
+ * report the unrecognized parameter in an
+ * 'Unrecognized Parameter Type' (in either an ERROR or in
+ * the INIT ACK).
+ *
+ * Return value:
+ * 0 - discard the chunk
+ * 1 - continue with the chunk
+ */
+static int sctp_process_unk_param(const struct sctp_association *asoc,
+ union sctp_params param,
+ struct sctp_chunk *chunk,
+ struct sctp_chunk **errp)
+{
+ int retval = 1;
+
+ switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
+ case SCTP_PARAM_ACTION_DISCARD:
+ retval = 0;
+ break;
+ case SCTP_PARAM_ACTION_DISCARD_ERR:
+ retval = 0;
+ /* Make an ERROR chunk, preparing enough room for
+ * returning multiple unknown parameters.
+ */
+ if (NULL == *errp)
+ *errp = sctp_make_op_error_space(asoc, chunk,
+ ntohs(chunk->chunk_hdr->length));
+
+ if (*errp)
+ sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
+ param.v,
+ WORD_ROUND(ntohs(param.p->length)));
+
+ break;
+ case SCTP_PARAM_ACTION_SKIP:
+ break;
+ case SCTP_PARAM_ACTION_SKIP_ERR:
+ /* Make an ERROR chunk, preparing enough room for
+ * returning multiple unknown parameters.
+ */
+ if (NULL == *errp)
+ *errp = sctp_make_op_error_space(asoc, chunk,
+ ntohs(chunk->chunk_hdr->length));
+
+ if (*errp) {
+ sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
+ param.v,
+ WORD_ROUND(ntohs(param.p->length)));
+ } else {
+ /* If there is no memory for generating the ERROR
+ * report as specified, an ABORT will be triggered
+ * to the peer and the association won't be
+ * established.
+ */
+ retval = 0;
+ }
+
+ break;
+ default:
+ break;
+ }
+
+ return retval;
+}
+
+/* Find unrecognized parameters in the chunk.
+ * Return values:
+ * 0 - discard the chunk
+ * 1 - continue with the chunk
+ */
+static int sctp_verify_param(const struct sctp_association *asoc,
+ union sctp_params param,
+ sctp_cid_t cid,
+ struct sctp_chunk *chunk,
+ struct sctp_chunk **err_chunk)
+{
+ int retval = 1;
+
+ /* FIXME - This routine is not looking at each parameter per the
+ * chunk type, i.e., unrecognized parameters should be further
+ * identified based on the chunk id.
+ */
+
+ switch (param.p->type) {
+ case SCTP_PARAM_IPV4_ADDRESS:
+ case SCTP_PARAM_IPV6_ADDRESS:
+ case SCTP_PARAM_COOKIE_PRESERVATIVE:
+ case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
+ case SCTP_PARAM_STATE_COOKIE:
+ case SCTP_PARAM_HEARTBEAT_INFO:
+ case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
+ case SCTP_PARAM_ECN_CAPABLE:
+ case SCTP_PARAM_ADAPTION_LAYER_IND:
+ break;
+
+ case SCTP_PARAM_HOST_NAME_ADDRESS:
+ /* Tell the peer, we won't support this param. */
+ return sctp_process_hn_param(asoc, param, chunk, err_chunk);
+ case SCTP_PARAM_FWD_TSN_SUPPORT:
+ if (sctp_prsctp_enable)
+ break;
+ /* Fall Through */
+ default:
+ SCTP_DEBUG_PRINTK("Unrecognized param: %d for chunk %d.\n",
+ ntohs(param.p->type), cid);
+ return sctp_process_unk_param(asoc, param, chunk, err_chunk);
+
+ break;
+ }
+ return retval;
+}
+
+/* Verify the INIT packet before we process it. */
+int sctp_verify_init(const struct sctp_association *asoc,
+ sctp_cid_t cid,
+ sctp_init_chunk_t *peer_init,
+ struct sctp_chunk *chunk,
+ struct sctp_chunk **errp)
+{
+ union sctp_params param;
+ int has_cookie = 0;
+
+ /* Verify stream values are non-zero. */
+ if ((0 == peer_init->init_hdr.num_outbound_streams) ||
+ (0 == peer_init->init_hdr.num_inbound_streams)) {
+
+ sctp_process_inv_mandatory(asoc, chunk, errp);
+ return 0;
+ }
+
+ /* Check for missing mandatory parameters. */
+ sctp_walk_params(param, peer_init, init_hdr.params) {
+
+ if (SCTP_PARAM_STATE_COOKIE == param.p->type)
+ has_cookie = 1;
+
+ } /* for (loop through all parameters) */
+
+ /* There is a possibility that a parameter length was bad and
+ * in that case we would have stoped walking the parameters.
+ * The current param.p would point at the bad one.
+ * Current consensus on the mailing list is to generate a PROTOCOL
+ * VIOLATION error. We build the ERROR chunk here and let the normal
+ * error handling code build and send the packet.
+ */
+ if (param.v < (void*)chunk->chunk_end - sizeof(sctp_paramhdr_t)) {
+ sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
+ return 0;
+ }
+
+ /* The only missing mandatory param possible today is
+ * the state cookie for an INIT-ACK chunk.
+ */
+ if ((SCTP_CID_INIT_ACK == cid) && !has_cookie) {
+ sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
+ chunk, errp);
+ return 0;
+ }
+
+ /* Find unrecognized parameters. */
+
+ sctp_walk_params(param, peer_init, init_hdr.params) {
+
+ if (!sctp_verify_param(asoc, param, cid, chunk, errp)) {
+ if (SCTP_PARAM_HOST_NAME_ADDRESS == param.p->type)
+ return 0;
+ else
+ return 1;
+ }
+
+ } /* for (loop through all parameters) */
+
+ return 1;
+}
+
+/* Unpack the parameters in an INIT packet into an association.
+ * Returns 0 on failure, else success.
+ * FIXME: This is an association method.
+ */
+int sctp_process_init(struct sctp_association *asoc, sctp_cid_t cid,
+ const union sctp_addr *peer_addr,
+ sctp_init_chunk_t *peer_init, int gfp)
+{
+ union sctp_params param;
+ struct sctp_transport *transport;
+ struct list_head *pos, *temp;
+ char *cookie;
+
+ /* We must include the address that the INIT packet came from.
+ * This is the only address that matters for an INIT packet.
+ * When processing a COOKIE ECHO, we retrieve the from address
+ * of the INIT from the cookie.
+ */
+
+ /* This implementation defaults to making the first transport
+ * added as the primary transport. The source address seems to
+ * be a a better choice than any of the embedded addresses.
+ */
+ if (peer_addr)
+ if(!sctp_assoc_add_peer(asoc, peer_addr, gfp))
+ goto nomem;
+
+ /* Process the initialization parameters. */
+
+ sctp_walk_params(param, peer_init, init_hdr.params) {
+
+ if (!sctp_process_param(asoc, param, peer_addr, gfp))
+ goto clean_up;
+ }
+
+ /* The fixed INIT headers are always in network byte
+ * order.
+ */
+ asoc->peer.i.init_tag =
+ ntohl(peer_init->init_hdr.init_tag);
+ asoc->peer.i.a_rwnd =
+ ntohl(peer_init->init_hdr.a_rwnd);
+ asoc->peer.i.num_outbound_streams =
+ ntohs(peer_init->init_hdr.num_outbound_streams);
+ asoc->peer.i.num_inbound_streams =
+ ntohs(peer_init->init_hdr.num_inbound_streams);
+ asoc->peer.i.initial_tsn =
+ ntohl(peer_init->init_hdr.initial_tsn);
+
+ /* Apply the upper bounds for output streams based on peer's
+ * number of inbound streams.
+ */
+ if (asoc->c.sinit_num_ostreams >
+ ntohs(peer_init->init_hdr.num_inbound_streams)) {
+ asoc->c.sinit_num_ostreams =
+ ntohs(peer_init->init_hdr.num_inbound_streams);
+ }
+
+ if (asoc->c.sinit_max_instreams >
+ ntohs(peer_init->init_hdr.num_outbound_streams)) {
+ asoc->c.sinit_max_instreams =
+ ntohs(peer_init->init_hdr.num_outbound_streams);
+ }
+
+ /* Copy Initiation tag from INIT to VT_peer in cookie. */
+ asoc->c.peer_vtag = asoc->peer.i.init_tag;
+
+ /* Peer Rwnd : Current calculated value of the peer's rwnd. */
+ asoc->peer.rwnd = asoc->peer.i.a_rwnd;
+
+ /* Copy cookie in case we need to resend COOKIE-ECHO. */
+ cookie = asoc->peer.cookie;
+ if (cookie) {
+ asoc->peer.cookie = kmalloc(asoc->peer.cookie_len, gfp);
+ if (!asoc->peer.cookie)
+ goto clean_up;
+ memcpy(asoc->peer.cookie, cookie, asoc->peer.cookie_len);
+ }
+
+ /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily
+ * high (for example, implementations MAY use the size of the receiver
+ * advertised window).
+ */
+ list_for_each(pos, &asoc->peer.transport_addr_list) {
+ transport = list_entry(pos, struct sctp_transport, transports);
+ transport->ssthresh = asoc->peer.i.a_rwnd;
+ }
+
+ /* Set up the TSN tracking pieces. */
+ sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_SIZE,
+ asoc->peer.i.initial_tsn);
+
+ /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number
+ *
+ * The stream sequence number in all the streams shall start
+ * from 0 when the association is established. Also, when the
+ * stream sequence number reaches the value 65535 the next
+ * stream sequence number shall be set to 0.
+ */
+
+ /* Allocate storage for the negotiated streams if it is not a temporary * association.
+ */
+ if (!asoc->temp) {
+ int assoc_id;
+ int error;
+
+ asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
+ asoc->c.sinit_num_ostreams, gfp);
+ if (!asoc->ssnmap)
+ goto clean_up;
+
+ retry:
+ if (unlikely(!idr_pre_get(&sctp_assocs_id, gfp)))
+ goto clean_up;
+ spin_lock_bh(&sctp_assocs_id_lock);
+ error = idr_get_new_above(&sctp_assocs_id, (void *)asoc, 1,
+ &assoc_id);
+ spin_unlock_bh(&sctp_assocs_id_lock);
+ if (error == -EAGAIN)
+ goto retry;
+ else if (error)
+ goto clean_up;
+
+ asoc->assoc_id = (sctp_assoc_t) assoc_id;
+ }
+
+ /* ADDIP Section 4.1 ASCONF Chunk Procedures
+ *
+ * When an endpoint has an ASCONF signaled change to be sent to the
+ * remote endpoint it should do the following:
+ * ...
+ * A2) A serial number should be assigned to the Chunk. The serial
+ * number should be a monotonically increasing number. All serial
+ * numbers are defined to be initialized at the start of the
+ * association to the same value as the Initial TSN.
+ */
+ asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1;
+ return 1;
+
+clean_up:
+ /* Release the transport structures. */
+ list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
+ transport = list_entry(pos, struct sctp_transport, transports);
+ list_del_init(pos);
+ sctp_transport_free(transport);
+ }
+nomem:
+ return 0;
+}
+
+
+/* Update asoc with the option described in param.
+ *
+ * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT
+ *
+ * asoc is the association to update.
+ * param is the variable length parameter to use for update.
+ * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO.
+ * If the current packet is an INIT we want to minimize the amount of
+ * work we do. In particular, we should not build transport
+ * structures for the addresses.
+ */
+static int sctp_process_param(struct sctp_association *asoc,
+ union sctp_params param,
+ const union sctp_addr *peer_addr,
+ int gfp)
+{
+ union sctp_addr addr;
+ int i;
+ __u16 sat;
+ int retval = 1;
+ sctp_scope_t scope;
+ time_t stale;
+ struct sctp_af *af;
+
+ /* We maintain all INIT parameters in network byte order all the
+ * time. This allows us to not worry about whether the parameters
+ * came from a fresh INIT, and INIT ACK, or were stored in a cookie.
+ */
+ switch (param.p->type) {
+ case SCTP_PARAM_IPV6_ADDRESS:
+ if (PF_INET6 != asoc->base.sk->sk_family)
+ break;
+ /* Fall through. */
+ case SCTP_PARAM_IPV4_ADDRESS:
+ af = sctp_get_af_specific(param_type2af(param.p->type));
+ af->from_addr_param(&addr, param.addr, asoc->peer.port, 0);
+ scope = sctp_scope(peer_addr);
+ if (sctp_in_scope(&addr, scope))
+ if (!sctp_assoc_add_peer(asoc, &addr, gfp))
+ return 0;
+ break;
+
+ case SCTP_PARAM_COOKIE_PRESERVATIVE:
+ if (!sctp_cookie_preserve_enable)
+ break;
+
+ stale = ntohl(param.life->lifespan_increment);
+
+ /* Suggested Cookie Life span increment's unit is msec,
+ * (1/1000sec).
+ */
+ asoc->cookie_life.tv_sec += stale / 1000;
+ asoc->cookie_life.tv_usec += (stale % 1000) * 1000;
+ break;
+
+ case SCTP_PARAM_HOST_NAME_ADDRESS:
+ SCTP_DEBUG_PRINTK("unimplemented SCTP_HOST_NAME_ADDRESS\n");
+ break;
+
+ case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES:
+ /* Turn off the default values first so we'll know which
+ * ones are really set by the peer.
+ */
+ asoc->peer.ipv4_address = 0;
+ asoc->peer.ipv6_address = 0;
+
+ /* Cycle through address types; avoid divide by 0. */
+ sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
+ if (sat)
+ sat /= sizeof(__u16);
+
+ for (i = 0; i < sat; ++i) {
+ switch (param.sat->types[i]) {
+ case SCTP_PARAM_IPV4_ADDRESS:
+ asoc->peer.ipv4_address = 1;
+ break;
+
+ case SCTP_PARAM_IPV6_ADDRESS:
+ asoc->peer.ipv6_address = 1;
+ break;
+
+ case SCTP_PARAM_HOST_NAME_ADDRESS:
+ asoc->peer.hostname_address = 1;
+ break;
+
+ default: /* Just ignore anything else. */
+ break;
+ };
+ }
+ break;
+
+ case SCTP_PARAM_STATE_COOKIE:
+ asoc->peer.cookie_len =
+ ntohs(param.p->length) - sizeof(sctp_paramhdr_t);
+ asoc->peer.cookie = param.cookie->body;
+ break;
+
+ case SCTP_PARAM_HEARTBEAT_INFO:
+ /* Would be odd to receive, but it causes no problems. */
+ break;
+
+ case SCTP_PARAM_UNRECOGNIZED_PARAMETERS:
+ /* Rejected during verify stage. */
+ break;
+
+ case SCTP_PARAM_ECN_CAPABLE:
+ asoc->peer.ecn_capable = 1;
+ break;
+
+ case SCTP_PARAM_ADAPTION_LAYER_IND:
+ asoc->peer.adaption_ind = param.aind->adaption_ind;
+ break;
+
+ case SCTP_PARAM_FWD_TSN_SUPPORT:
+ if (sctp_prsctp_enable) {
+ asoc->peer.prsctp_capable = 1;
+ break;
+ }
+ /* Fall Through */
+ default:
+ /* Any unrecognized parameters should have been caught
+ * and handled by sctp_verify_param() which should be
+ * called prior to this routine. Simply log the error
+ * here.
+ */
+ SCTP_DEBUG_PRINTK("Ignoring param: %d for association %p.\n",
+ ntohs(param.p->type), asoc);
+ break;
+ };
+
+ return retval;
+}
+
+/* Select a new verification tag. */
+__u32 sctp_generate_tag(const struct sctp_endpoint *ep)
+{
+ /* I believe that this random number generator complies with RFC1750.
+ * A tag of 0 is reserved for special cases (e.g. INIT).
+ */
+ __u32 x;
+
+ do {
+ get_random_bytes(&x, sizeof(__u32));
+ } while (x == 0);
+
+ return x;
+}
+
+/* Select an initial TSN to send during startup. */
+__u32 sctp_generate_tsn(const struct sctp_endpoint *ep)
+{
+ __u32 retval;
+
+ get_random_bytes(&retval, sizeof(__u32));
+ return retval;
+}
+
+/*
+ * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF)
+ * 0 1 2 3
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Type = 0xC1 | Chunk Flags | Chunk Length |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Serial Number |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Address Parameter |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | ASCONF Parameter #1 |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * \ \
+ * / .... /
+ * \ \
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | ASCONF Parameter #N |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ * Address Parameter and other parameter will not be wrapped in this function
+ */
+static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
+ union sctp_addr *addr,
+ int vparam_len)
+{
+ sctp_addiphdr_t asconf;
+ struct sctp_chunk *retval;
+ int length = sizeof(asconf) + vparam_len;
+ union sctp_addr_param addrparam;
+ int addrlen;
+ struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
+
+ addrlen = af->to_addr_param(addr, &addrparam);
+ if (!addrlen)
+ return NULL;
+ length += addrlen;
+
+ /* Create the chunk. */
+ retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF, 0, length);
+ if (!retval)
+ return NULL;
+
+ asconf.serial = htonl(asoc->addip_serial++);
+
+ retval->subh.addip_hdr =
+ sctp_addto_chunk(retval, sizeof(asconf), &asconf);
+ retval->param_hdr.v =
+ sctp_addto_chunk(retval, addrlen, &addrparam);
+
+ return retval;
+}
+
+/* ADDIP
+ * 3.2.1 Add IP Address
+ * 0 1 2 3
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Type = 0xC001 | Length = Variable |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | ASCONF-Request Correlation ID |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Address Parameter |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ * 3.2.2 Delete IP Address
+ * 0 1 2 3
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Type = 0xC002 | Length = Variable |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | ASCONF-Request Correlation ID |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Address Parameter |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ */
+struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
+ union sctp_addr *laddr,
+ struct sockaddr *addrs,
+ int addrcnt,
+ __u16 flags)
+{
+ sctp_addip_param_t param;
+ struct sctp_chunk *retval;
+ union sctp_addr_param addr_param;
+ union sctp_addr *addr;
+ void *addr_buf;
+ struct sctp_af *af;
+ int paramlen = sizeof(param);
+ int addr_param_len = 0;
+ int totallen = 0;
+ int i;
+
+ /* Get total length of all the address parameters. */
+ addr_buf = addrs;
+ for (i = 0; i < addrcnt; i++) {
+ addr = (union sctp_addr *)addr_buf;
+ af = sctp_get_af_specific(addr->v4.sin_family);
+ addr_param_len = af->to_addr_param(addr, &addr_param);
+
+ totallen += paramlen;
+ totallen += addr_param_len;
+
+ addr_buf += af->sockaddr_len;
+ }
+
+ /* Create an asconf chunk with the required length. */
+ retval = sctp_make_asconf(asoc, laddr, totallen);
+ if (!retval)
+ return NULL;
+
+ /* Add the address parameters to the asconf chunk. */
+ addr_buf = addrs;
+ for (i = 0; i < addrcnt; i++) {
+ addr = (union sctp_addr *)addr_buf;
+ af = sctp_get_af_specific(addr->v4.sin_family);
+ addr_param_len = af->to_addr_param(addr, &addr_param);
+ param.param_hdr.type = flags;
+ param.param_hdr.length = htons(paramlen + addr_param_len);
+ param.crr_id = i;
+
+ sctp_addto_chunk(retval, paramlen, &param);
+ sctp_addto_chunk(retval, addr_param_len, &addr_param);
+
+ addr_buf += af->sockaddr_len;
+ }
+ return retval;
+}
+
+/* ADDIP
+ * 3.2.4 Set Primary IP Address
+ * 0 1 2 3
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Type =0xC004 | Length = Variable |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | ASCONF-Request Correlation ID |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Address Parameter |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ * Create an ASCONF chunk with Set Primary IP address parameter.
+ */
+struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
+ union sctp_addr *addr)
+{
+ sctp_addip_param_t param;
+ struct sctp_chunk *retval;
+ int len = sizeof(param);
+ union sctp_addr_param addrparam;
+ int addrlen;
+ struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
+
+ addrlen = af->to_addr_param(addr, &addrparam);
+ if (!addrlen)
+ return NULL;
+ len += addrlen;
+
+ /* Create the chunk and make asconf header. */
+ retval = sctp_make_asconf(asoc, addr, len);
+ if (!retval)
+ return NULL;
+
+ param.param_hdr.type = SCTP_PARAM_SET_PRIMARY;
+ param.param_hdr.length = htons(len);
+ param.crr_id = 0;
+
+ sctp_addto_chunk(retval, sizeof(param), &param);
+ sctp_addto_chunk(retval, addrlen, &addrparam);
+
+ return retval;
+}
+
+/* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK)
+ * 0 1 2 3
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Type = 0x80 | Chunk Flags | Chunk Length |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Serial Number |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | ASCONF Parameter Response#1 |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * \ \
+ * / .... /
+ * \ \
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | ASCONF Parameter Response#N |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ * Create an ASCONF_ACK chunk with enough space for the parameter responses.
+ */
+static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
+ __u32 serial, int vparam_len)
+{
+ sctp_addiphdr_t asconf;
+ struct sctp_chunk *retval;
+ int length = sizeof(asconf) + vparam_len;
+
+ /* Create the chunk. */
+ retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF_ACK, 0, length);
+ if (!retval)
+ return NULL;
+
+ asconf.serial = htonl(serial);
+
+ retval->subh.addip_hdr =
+ sctp_addto_chunk(retval, sizeof(asconf), &asconf);
+
+ return retval;
+}
+
+/* Add response parameters to an ASCONF_ACK chunk. */
+static void sctp_add_asconf_response(struct sctp_chunk *chunk, __u32 crr_id,
+ __u16 err_code, sctp_addip_param_t *asconf_param)
+{
+ sctp_addip_param_t ack_param;
+ sctp_errhdr_t err_param;
+ int asconf_param_len = 0;
+ int err_param_len = 0;
+ __u16 response_type;
+
+ if (SCTP_ERROR_NO_ERROR == err_code) {
+ response_type = SCTP_PARAM_SUCCESS_REPORT;
+ } else {
+ response_type = SCTP_PARAM_ERR_CAUSE;
+ err_param_len = sizeof(err_param);
+ if (asconf_param)
+ asconf_param_len =
+ ntohs(asconf_param->param_hdr.length);
+ }
+
+ /* Add Success Indication or Error Cause Indication parameter. */
+ ack_param.param_hdr.type = response_type;
+ ack_param.param_hdr.length = htons(sizeof(ack_param) +
+ err_param_len +
+ asconf_param_len);
+ ack_param.crr_id = crr_id;
+ sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param);
+
+ if (SCTP_ERROR_NO_ERROR == err_code)
+ return;
+
+ /* Add Error Cause parameter. */
+ err_param.cause = err_code;
+ err_param.length = htons(err_param_len + asconf_param_len);
+ sctp_addto_chunk(chunk, err_param_len, &err_param);
+
+ /* Add the failed TLV copied from ASCONF chunk. */
+ if (asconf_param)
+ sctp_addto_chunk(chunk, asconf_param_len, asconf_param);
+}
+
+/* Process a asconf parameter. */
+static __u16 sctp_process_asconf_param(struct sctp_association *asoc,
+ struct sctp_chunk *asconf,
+ sctp_addip_param_t *asconf_param)
+{
+ struct sctp_transport *peer;
+ struct sctp_af *af;
+ union sctp_addr addr;
+ struct list_head *pos;
+ union sctp_addr_param *addr_param;
+
+ addr_param = (union sctp_addr_param *)
+ ((void *)asconf_param + sizeof(sctp_addip_param_t));
+
+ af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
+ if (unlikely(!af))
+ return SCTP_ERROR_INV_PARAM;
+
+ af->from_addr_param(&addr, addr_param, asoc->peer.port, 0);
+ switch (asconf_param->param_hdr.type) {
+ case SCTP_PARAM_ADD_IP:
+ /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
+ * request and does not have the local resources to add this
+ * new address to the association, it MUST return an Error
+ * Cause TLV set to the new error code 'Operation Refused
+ * Due to Resource Shortage'.
+ */
+
+ peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC);
+ if (!peer)
+ return SCTP_ERROR_RSRC_LOW;
+
+ /* Start the heartbeat timer. */
+ if (!mod_timer(&peer->hb_timer, sctp_transport_timeout(peer)))
+ sctp_transport_hold(peer);
+ break;
+ case SCTP_PARAM_DEL_IP:
+ /* ADDIP 4.3 D7) If a request is received to delete the
+ * last remaining IP address of a peer endpoint, the receiver
+ * MUST send an Error Cause TLV with the error cause set to the
+ * new error code 'Request to Delete Last Remaining IP Address'.
+ */
+ pos = asoc->peer.transport_addr_list.next;
+ if (pos->next == &asoc->peer.transport_addr_list)
+ return SCTP_ERROR_DEL_LAST_IP;
+
+ /* ADDIP 4.3 D8) If a request is received to delete an IP
+ * address which is also the source address of the IP packet
+ * which contained the ASCONF chunk, the receiver MUST reject
+ * this request. To reject the request the receiver MUST send
+ * an Error Cause TLV set to the new error code 'Request to
+ * Delete Source IP Address'
+ */
+ if (sctp_cmp_addr_exact(sctp_source(asconf), &addr))
+ return SCTP_ERROR_DEL_SRC_IP;
+
+ sctp_assoc_del_peer(asoc, &addr);
+ break;
+ case SCTP_PARAM_SET_PRIMARY:
+ peer = sctp_assoc_lookup_paddr(asoc, &addr);
+ if (!peer)
+ return SCTP_ERROR_INV_PARAM;
+
+ sctp_assoc_set_primary(asoc, peer);
+ break;
+ default:
+ return SCTP_ERROR_INV_PARAM;
+ break;
+ }
+
+ return SCTP_ERROR_NO_ERROR;
+}
+
+/* Process an incoming ASCONF chunk with the next expected serial no. and
+ * return an ASCONF_ACK chunk to be sent in response.
+ */
+struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
+ struct sctp_chunk *asconf)
+{
+ sctp_addiphdr_t *hdr;
+ union sctp_addr_param *addr_param;
+ sctp_addip_param_t *asconf_param;
+ struct sctp_chunk *asconf_ack;
+
+ __u16 err_code;
+ int length = 0;
+ int chunk_len = asconf->skb->len;
+ __u32 serial;
+ int all_param_pass = 1;
+
+ hdr = (sctp_addiphdr_t *)asconf->skb->data;
+ serial = ntohl(hdr->serial);
+
+ /* Skip the addiphdr and store a pointer to address parameter. */
+ length = sizeof(sctp_addiphdr_t);
+ addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
+ chunk_len -= length;
+
+ /* Skip the address parameter and store a pointer to the first
+ * asconf paramter.
+ */
+ length = ntohs(addr_param->v4.param_hdr.length);
+ asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
+ chunk_len -= length;
+
+ /* create an ASCONF_ACK chunk.
+ * Based on the definitions of parameters, we know that the size of
+ * ASCONF_ACK parameters are less than or equal to the twice of ASCONF
+ * paramters.
+ */
+ asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 2);
+ if (!asconf_ack)
+ goto done;
+
+ /* Process the TLVs contained within the ASCONF chunk. */
+ while (chunk_len > 0) {
+ err_code = sctp_process_asconf_param(asoc, asconf,
+ asconf_param);
+ /* ADDIP 4.1 A7)
+ * If an error response is received for a TLV parameter,
+ * all TLVs with no response before the failed TLV are
+ * considered successful if not reported. All TLVs after
+ * the failed response are considered unsuccessful unless
+ * a specific success indication is present for the parameter.
+ */
+ if (SCTP_ERROR_NO_ERROR != err_code)
+ all_param_pass = 0;
+
+ if (!all_param_pass)
+ sctp_add_asconf_response(asconf_ack,
+ asconf_param->crr_id, err_code,
+ asconf_param);
+
+ /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add
+ * an IP address sends an 'Out of Resource' in its response, it
+ * MUST also fail any subsequent add or delete requests bundled
+ * in the ASCONF.
+ */
+ if (SCTP_ERROR_RSRC_LOW == err_code)
+ goto done;
+
+ /* Move to the next ASCONF param. */
+ length = ntohs(asconf_param->param_hdr.length);
+ asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
+ length);
+ chunk_len -= length;
+ }
+
+done:
+ asoc->peer.addip_serial++;
+
+ /* If we are sending a new ASCONF_ACK hold a reference to it in assoc
+ * after freeing the reference to old asconf ack if any.
+ */
+ if (asconf_ack) {
+ if (asoc->addip_last_asconf_ack)
+ sctp_chunk_free(asoc->addip_last_asconf_ack);
+
+ sctp_chunk_hold(asconf_ack);
+ asoc->addip_last_asconf_ack = asconf_ack;
+ }
+
+ return asconf_ack;
+}
+
+/* Process a asconf parameter that is successfully acked. */
+static int sctp_asconf_param_success(struct sctp_association *asoc,
+ sctp_addip_param_t *asconf_param)
+{
+ struct sctp_af *af;
+ union sctp_addr addr;
+ struct sctp_bind_addr *bp = &asoc->base.bind_addr;
+ union sctp_addr_param *addr_param;
+ struct list_head *pos;
+ struct sctp_transport *transport;
+ int retval = 0;
+
+ addr_param = (union sctp_addr_param *)
+ ((void *)asconf_param + sizeof(sctp_addip_param_t));
+
+ /* We have checked the packet before, so we do not check again. */
+ af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type));
+ af->from_addr_param(&addr, addr_param, bp->port, 0);
+
+ switch (asconf_param->param_hdr.type) {
+ case SCTP_PARAM_ADD_IP:
+ sctp_local_bh_disable();
+ sctp_write_lock(&asoc->base.addr_lock);
+ retval = sctp_add_bind_addr(bp, &addr, GFP_ATOMIC);
+ sctp_write_unlock(&asoc->base.addr_lock);
+ sctp_local_bh_enable();
+ break;
+ case SCTP_PARAM_DEL_IP:
+ sctp_local_bh_disable();
+ sctp_write_lock(&asoc->base.addr_lock);
+ retval = sctp_del_bind_addr(bp, &addr);
+ sctp_write_unlock(&asoc->base.addr_lock);
+ sctp_local_bh_enable();
+ list_for_each(pos, &asoc->peer.transport_addr_list) {
+ transport = list_entry(pos, struct sctp_transport,
+ transports);
+ sctp_transport_route(transport, NULL,
+ sctp_sk(asoc->base.sk));
+ }
+ break;
+ default:
+ break;
+ }
+
+ return retval;
+}
+
+/* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk
+ * for the given asconf parameter. If there is no response for this parameter,
+ * return the error code based on the third argument 'no_err'.
+ * ADDIP 4.1
+ * A7) If an error response is received for a TLV parameter, all TLVs with no
+ * response before the failed TLV are considered successful if not reported.
+ * All TLVs after the failed response are considered unsuccessful unless a
+ * specific success indication is present for the parameter.
+ */
+static __u16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
+ sctp_addip_param_t *asconf_param,
+ int no_err)
+{
+ sctp_addip_param_t *asconf_ack_param;
+ sctp_errhdr_t *err_param;
+ int length;
+ int asconf_ack_len = asconf_ack->skb->len;
+ __u16 err_code;
+
+ if (no_err)
+ err_code = SCTP_ERROR_NO_ERROR;
+ else
+ err_code = SCTP_ERROR_REQ_REFUSED;
+
+ /* Skip the addiphdr from the asconf_ack chunk and store a pointer to
+ * the first asconf_ack parameter.
+ */
+ length = sizeof(sctp_addiphdr_t);
+ asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data +
+ length);
+ asconf_ack_len -= length;
+
+ while (asconf_ack_len > 0) {
+ if (asconf_ack_param->crr_id == asconf_param->crr_id) {
+ switch(asconf_ack_param->param_hdr.type) {
+ case SCTP_PARAM_SUCCESS_REPORT:
+ return SCTP_ERROR_NO_ERROR;
+ case SCTP_PARAM_ERR_CAUSE:
+ length = sizeof(sctp_addip_param_t);
+ err_param = (sctp_errhdr_t *)
+ ((void *)asconf_ack_param + length);
+ asconf_ack_len -= length;
+ if (asconf_ack_len > 0)
+ return err_param->cause;
+ else
+ return SCTP_ERROR_INV_PARAM;
+ break;
+ default:
+ return SCTP_ERROR_INV_PARAM;
+ }
+ }
+
+ length = ntohs(asconf_ack_param->param_hdr.length);
+ asconf_ack_param = (sctp_addip_param_t *)
+ ((void *)asconf_ack_param + length);
+ asconf_ack_len -= length;
+ }
+
+ return err_code;
+}
+
+/* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */
+int sctp_process_asconf_ack(struct sctp_association *asoc,
+ struct sctp_chunk *asconf_ack)
+{
+ struct sctp_chunk *asconf = asoc->addip_last_asconf;
+ union sctp_addr_param *addr_param;
+ sctp_addip_param_t *asconf_param;
+ int length = 0;
+ int asconf_len = asconf->skb->len;
+ int all_param_pass = 0;
+ int no_err = 1;
+ int retval = 0;
+ __u16 err_code = SCTP_ERROR_NO_ERROR;
+
+ /* Skip the chunkhdr and addiphdr from the last asconf sent and store
+ * a pointer to address parameter.
+ */
+ length = sizeof(sctp_addip_chunk_t);
+ addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
+ asconf_len -= length;
+
+ /* Skip the address parameter in the last asconf sent and store a
+ * pointer to the first asconf paramter.
+ */
+ length = ntohs(addr_param->v4.param_hdr.length);
+ asconf_param = (sctp_addip_param_t *)((void *)addr_param + length);
+ asconf_len -= length;
+
+ /* ADDIP 4.1
+ * A8) If there is no response(s) to specific TLV parameter(s), and no
+ * failures are indicated, then all request(s) are considered
+ * successful.
+ */
+ if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t))
+ all_param_pass = 1;
+
+ /* Process the TLVs contained in the last sent ASCONF chunk. */
+ while (asconf_len > 0) {
+ if (all_param_pass)
+ err_code = SCTP_ERROR_NO_ERROR;
+ else {
+ err_code = sctp_get_asconf_response(asconf_ack,
+ asconf_param,
+ no_err);
+ if (no_err && (SCTP_ERROR_NO_ERROR != err_code))
+ no_err = 0;
+ }
+
+ switch (err_code) {
+ case SCTP_ERROR_NO_ERROR:
+ retval = sctp_asconf_param_success(asoc, asconf_param);
+ break;
+
+ case SCTP_ERROR_RSRC_LOW:
+ retval = 1;
+ break;
+
+ case SCTP_ERROR_INV_PARAM:
+ /* Disable sending this type of asconf parameter in
+ * future.
+ */
+ asoc->peer.addip_disabled_mask |=
+ asconf_param->param_hdr.type;
+ break;
+
+ case SCTP_ERROR_REQ_REFUSED:
+ case SCTP_ERROR_DEL_LAST_IP:
+ case SCTP_ERROR_DEL_SRC_IP:
+ default:
+ break;
+ }
+
+ /* Skip the processed asconf parameter and move to the next
+ * one.
+ */
+ length = ntohs(asconf_param->param_hdr.length);
+ asconf_param = (sctp_addip_param_t *)((void *)asconf_param +
+ length);
+ asconf_len -= length;
+ }
+
+ /* Free the cached last sent asconf chunk. */
+ sctp_chunk_free(asconf);
+ asoc->addip_last_asconf = NULL;
+
+ /* Send the next asconf chunk from the addip chunk queue. */
+ asconf = (struct sctp_chunk *)__skb_dequeue(&asoc->addip_chunks);
+ if (asconf) {
+ /* Hold the chunk until an ASCONF_ACK is received. */
+ sctp_chunk_hold(asconf);
+ if (sctp_primitive_ASCONF(asoc, asconf))
+ sctp_chunk_free(asconf);
+ else
+ asoc->addip_last_asconf = asconf;
+ }
+
+ return retval;
+}
+
+/* Make a FWD TSN chunk. */
+struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
+ __u32 new_cum_tsn, size_t nstreams,
+ struct sctp_fwdtsn_skip *skiplist)
+{
+ struct sctp_chunk *retval = NULL;
+ struct sctp_fwdtsn_chunk *ftsn_chunk;
+ struct sctp_fwdtsn_hdr ftsn_hdr;
+ struct sctp_fwdtsn_skip skip;
+ size_t hint;
+ int i;
+
+ hint = (nstreams + 1) * sizeof(__u32);
+
+ /* Maybe set the T-bit if we have no association. */
+ retval = sctp_make_chunk(asoc, SCTP_CID_FWD_TSN, 0, hint);
+
+ if (!retval)
+ return NULL;
+
+ ftsn_chunk = (struct sctp_fwdtsn_chunk *)retval->subh.fwdtsn_hdr;
+
+ ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn);
+ retval->subh.fwdtsn_hdr =
+ sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr);
+
+ for (i = 0; i < nstreams; i++) {
+ skip.stream = skiplist[i].stream;
+ skip.ssn = skiplist[i].ssn;
+ sctp_addto_chunk(retval, sizeof(skip), &skip);
+ }
+
+ return retval;
+}
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