Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 2766 insertions, 0 deletions

diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
new file mode 100644
index 000000000000..1db12cc18cf7
--- /dev/null
+++ b/net/sctp/sm_make_chunk.c
@@ -0,0 +1,2766 @@
+/* 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;
+}