sm_make_chunk.c 114.7 KB
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/* SCTP kernel implementation
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 * (C) Copyright IBM Corp. 2001, 2004
 * Copyright (c) 1999-2000 Cisco, Inc.
 * Copyright (c) 1999-2001 Motorola, Inc.
 * Copyright (c) 2001-2002 Intel Corp.
 *
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 * This file is part of the SCTP kernel implementation
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 *
 * 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.
 *
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 * This SCTP implementation is free software;
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 * 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.
 *
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 * This SCTP implementation is distributed in the hope that it
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 * 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
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 * along with GNU CC; see the file COPYING.  If not, see
 * <http://www.gnu.org/licenses/>.
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 *
 * Please send any bug reports or fixes you make to the
 * email address(es):
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 *    lksctp developers <linux-sctp@vger.kernel.org>
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 *
 * 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>
 */

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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

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#include <crypto/hash.h>
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#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/net.h>
#include <linux/inet.h>
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#include <linux/scatterlist.h>
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#include <linux/slab.h>
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#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>

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static struct sctp_chunk *sctp_make_control(const struct sctp_association *asoc,
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					    __u8 type, __u8 flags, int paylen,
					    gfp_t gfp);
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static struct sctp_chunk *sctp_make_data(const struct sctp_association *asoc,
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					 __u8 flags, int paylen, gfp_t gfp);
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static struct sctp_chunk *_sctp_make_chunk(const struct sctp_association *asoc,
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					   __u8 type, __u8 flags, int paylen,
					   gfp_t gfp);
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static struct sctp_cookie_param *sctp_pack_cookie(
					const struct sctp_endpoint *ep,
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					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,
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			      gfp_t gfp);
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static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
			      const void *data);
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static void  *sctp_addto_chunk_fixed(struct sctp_chunk *, int len,
				     const void *data);
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/* Control chunk destructor */
static void sctp_control_release_owner(struct sk_buff *skb)
{
	/*TODO: do memory release */
}

static void sctp_control_set_owner_w(struct sctp_chunk *chunk)
{
	struct sctp_association *asoc = chunk->asoc;
	struct sk_buff *skb = chunk->skb;

	/* TODO: properly account for control chunks.
	 * To do it right we'll need:
	 *  1) endpoint if association isn't known.
	 *  2) proper memory accounting.
	 *
	 *  For now don't do anything for now.
	 */
	skb->sk = asoc ? asoc->base.sk : NULL;
	skb->destructor = sctp_control_release_owner;
}

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/* What was the inbound interface for this chunk? */
int sctp_chunk_iif(const struct sctp_chunk *chunk)
{
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	struct sk_buff *skb = chunk->skb;
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	return SCTP_INPUT_CB(skb)->af->skb_iif(skb);
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}

/* 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,
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	cpu_to_be16(sizeof(struct sctp_paramhdr)),
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};
static const struct sctp_paramhdr prsctp_param = {
	SCTP_PARAM_FWD_TSN_SUPPORT,
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	cpu_to_be16(sizeof(struct sctp_paramhdr)),
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};

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/* A helper to initialize an op error inside a
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 * provided chunk, as most cause codes will be embedded inside an
 * abort chunk.
 */
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void sctp_init_cause(struct sctp_chunk *chunk, __be16 cause_code,
		     size_t paylen)
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{
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	struct sctp_errhdr err;
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	__u16 len;

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	/* Cause code constants are now defined in network order.  */
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	err.cause = cause_code;
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	len = sizeof(err) + paylen;
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	err.length  = htons(len);
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	chunk->subh.err_hdr = sctp_addto_chunk(chunk, sizeof(err), &err);
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}

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/* A helper to initialize an op error inside a
 * provided chunk, as most cause codes will be embedded inside an
 * abort chunk.  Differs from sctp_init_cause in that it won't oops
 * if there isn't enough space in the op error chunk
 */
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static int sctp_init_cause_fixed(struct sctp_chunk *chunk, __be16 cause_code,
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				 size_t paylen)
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{
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	struct sctp_errhdr err;
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	__u16 len;

	/* Cause code constants are now defined in network order.  */
	err.cause = cause_code;
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	len = sizeof(err) + paylen;
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	err.length  = htons(len);

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	if (skb_tailroom(chunk->skb) < len)
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		return -ENOSPC;
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	chunk->subh.err_hdr = sctp_addto_chunk_fixed(chunk, sizeof(err), &err);

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	return 0;
}
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/* 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,
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				  const struct sctp_bind_addr *bp,
				  gfp_t gfp, int vparam_len)
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{
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	struct net *net = sock_net(asoc->base.sk);
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	struct sctp_supported_ext_param ext_param;
	struct sctp_adaptation_ind_param aiparam;
	struct sctp_paramhdr *auth_chunks = NULL;
	struct sctp_paramhdr *auth_hmacs = NULL;
	struct sctp_supported_addrs_param sat;
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	struct sctp_endpoint *ep = asoc->ep;
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	struct sctp_chunk *retval = NULL;
	int num_types, addrs_len = 0;
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	struct sctp_inithdr init;
	union sctp_params addrs;
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	struct sctp_sock *sp;
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	__u8 extensions[5];
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	size_t chunksize;
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	__be16 types[2];
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	int num_ext = 0;
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	/* 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.
	 */

	/* 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);

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	chunksize = sizeof(init) + addrs_len;
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	chunksize += SCTP_PAD4(SCTP_SAT_LEN(num_types));
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	chunksize += sizeof(ecap_param);
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	if (asoc->prsctp_enable)
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		chunksize += sizeof(prsctp_param);

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	/* ADDIP: Section 4.2.7:
	 *  An implementation supporting this extension [ADDIP] MUST list
	 *  the ASCONF,the ASCONF-ACK, and the AUTH  chunks in its INIT and
	 *  INIT-ACK parameters.
	 */
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	if (net->sctp.addip_enable) {
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		extensions[num_ext] = SCTP_CID_ASCONF;
		extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
		num_ext += 2;
	}

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	if (asoc->reconf_enable) {
		extensions[num_ext] = SCTP_CID_RECONF;
		num_ext += 1;
	}

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	if (sp->adaptation_ind)
		chunksize += sizeof(aiparam);

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	if (sp->strm_interleave) {
		extensions[num_ext] = SCTP_CID_I_DATA;
		num_ext += 1;
	}

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	chunksize += vparam_len;

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	/* Account for AUTH related parameters */
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	if (ep->auth_enable) {
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		/* Add random parameter length*/
		chunksize += sizeof(asoc->c.auth_random);

		/* Add HMACS parameter length if any were defined */
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		auth_hmacs = (struct sctp_paramhdr *)asoc->c.auth_hmacs;
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		if (auth_hmacs->length)
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			chunksize += SCTP_PAD4(ntohs(auth_hmacs->length));
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		else
			auth_hmacs = NULL;

		/* Add CHUNKS parameter length */
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		auth_chunks = (struct sctp_paramhdr *)asoc->c.auth_chunks;
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		if (auth_chunks->length)
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			chunksize += SCTP_PAD4(ntohs(auth_chunks->length));
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		else
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			auth_chunks = NULL;
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		extensions[num_ext] = SCTP_CID_AUTH;
		num_ext += 1;
	}

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	/* If we have any extensions to report, account for that */
	if (num_ext)
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		chunksize += SCTP_PAD4(sizeof(ext_param) + num_ext);
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	/* 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.]
	 */

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	retval = sctp_make_control(asoc, SCTP_CID_INIT, 0, chunksize, gfp);
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	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);
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	/* Add the supported extensions parameter.  Be nice and add this
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	 * fist before addiding the parameters for the extensions themselves
	 */
	if (num_ext) {
		ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
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		ext_param.param_hdr.length = htons(sizeof(ext_param) + num_ext);
		sctp_addto_chunk(retval, sizeof(ext_param), &ext_param);
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		sctp_addto_param(retval, num_ext, extensions);
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	}

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	if (asoc->prsctp_enable)
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		sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);
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	if (sp->adaptation_ind) {
		aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
		aiparam.param_hdr.length = htons(sizeof(aiparam));
		aiparam.adaptation_ind = htonl(sp->adaptation_ind);
		sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
	}
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	/* Add SCTP-AUTH chunks to the parameter list */
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	if (ep->auth_enable) {
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		sctp_addto_chunk(retval, sizeof(asoc->c.auth_random),
				 asoc->c.auth_random);
		if (auth_hmacs)
			sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
					auth_hmacs);
		if (auth_chunks)
			sctp_addto_chunk(retval, ntohs(auth_chunks->length),
					auth_chunks);
	}
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nodata:
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	kfree(addrs.v);
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	return retval;
}

struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
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				      const struct sctp_chunk *chunk,
				      gfp_t gfp, int unkparam_len)
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{
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	struct sctp_supported_ext_param ext_param;
	struct sctp_adaptation_ind_param aiparam;
	struct sctp_paramhdr *auth_chunks = NULL;
	struct sctp_paramhdr *auth_random = NULL;
	struct sctp_paramhdr *auth_hmacs = NULL;
	struct sctp_chunk *retval = NULL;
	struct sctp_cookie_param *cookie;
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	struct sctp_inithdr initack;
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	union sctp_params addrs;
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	struct sctp_sock *sp;
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	__u8 extensions[5];
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	size_t chunksize;
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	int num_ext = 0;
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	int cookie_len;
	int addrs_len;
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	/* 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.
	 */
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	sp = sctp_sk(asoc->base.sk);
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	chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len;

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	/* Tell peer that we'll do ECN only if peer advertised such cap.  */
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	if (asoc->peer.ecn_capable)
		chunksize += sizeof(ecap_param);

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	if (asoc->peer.prsctp_capable)
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		chunksize += sizeof(prsctp_param);

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	if (asoc->peer.asconf_capable) {
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		extensions[num_ext] = SCTP_CID_ASCONF;
		extensions[num_ext+1] = SCTP_CID_ASCONF_ACK;
		num_ext += 2;
	}

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	if (asoc->peer.reconf_capable) {
		extensions[num_ext] = SCTP_CID_RECONF;
		num_ext += 1;
	}

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	if (sp->adaptation_ind)
		chunksize += sizeof(aiparam);
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	if (asoc->intl_enable) {
		extensions[num_ext] = SCTP_CID_I_DATA;
		num_ext += 1;
	}

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	if (asoc->peer.auth_capable) {
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		auth_random = (struct sctp_paramhdr *)asoc->c.auth_random;
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		chunksize += ntohs(auth_random->length);

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		auth_hmacs = (struct sctp_paramhdr *)asoc->c.auth_hmacs;
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		if (auth_hmacs->length)
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			chunksize += SCTP_PAD4(ntohs(auth_hmacs->length));
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		else
			auth_hmacs = NULL;

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		auth_chunks = (struct sctp_paramhdr *)asoc->c.auth_chunks;
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		if (auth_chunks->length)
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			chunksize += SCTP_PAD4(ntohs(auth_chunks->length));
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		else
			auth_chunks = NULL;

		extensions[num_ext] = SCTP_CID_AUTH;
		num_ext += 1;
	}

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	if (num_ext)
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		chunksize += SCTP_PAD4(sizeof(ext_param) + num_ext);
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	/* Now allocate and fill out the chunk.  */
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	retval = sctp_make_control(asoc, SCTP_CID_INIT_ACK, 0, chunksize, gfp);
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	if (!retval)
		goto nomem_chunk;

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	/* 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.]
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	 */
	retval->transport = chunk->transport;
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	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);
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	if (num_ext) {
		ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT;
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		ext_param.param_hdr.length = htons(sizeof(ext_param) + num_ext);
		sctp_addto_chunk(retval, sizeof(ext_param), &ext_param);
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		sctp_addto_param(retval, num_ext, extensions);
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	}
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	if (asoc->peer.prsctp_capable)
		sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param);

509 510 511 512 513 514
	if (sp->adaptation_ind) {
		aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND;
		aiparam.param_hdr.length = htons(sizeof(aiparam));
		aiparam.adaptation_ind = htonl(sp->adaptation_ind);
		sctp_addto_chunk(retval, sizeof(aiparam), &aiparam);
	}
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516 517 518 519 520 521 522 523 524 525 526
	if (asoc->peer.auth_capable) {
		sctp_addto_chunk(retval, ntohs(auth_random->length),
				 auth_random);
		if (auth_hmacs)
			sctp_addto_chunk(retval, ntohs(auth_hmacs->length),
					auth_hmacs);
		if (auth_chunks)
			sctp_addto_chunk(retval, ntohs(auth_chunks->length),
					auth_chunks);
	}

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	/* We need to remove the const qualifier at this point.  */
	retval->asoc = (struct sctp_association *) asoc;

nomem_chunk:
	kfree(cookie);
nomem_cookie:
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Jesper Juhl 已提交
533
	kfree(addrs.v);
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	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,
572
					 const struct sctp_chunk *chunk)
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{
	struct sctp_chunk *retval;
	int cookie_len;
576
	void *cookie;
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	cookie = asoc->peer.cookie;
	cookie_len = asoc->peer.cookie_len;

	/* Build a cookie echo chunk.  */
582 583
	retval = sctp_make_control(asoc, SCTP_CID_COOKIE_ECHO, 0,
				   cookie_len, GFP_ATOMIC);
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	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,
624
					const struct sctp_chunk *chunk)
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{
	struct sctp_chunk *retval;

628
	retval = sctp_make_control(asoc, SCTP_CID_COOKIE_ACK, 0, 0, GFP_ATOMIC);
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629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668

	/* 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,
669 670
				 const __u32 lowest_tsn,
				 const struct sctp_chunk *chunk)
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{
	struct sctp_chunk *retval;
673
	struct sctp_cwrhdr cwr;
L
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	cwr.lowest_tsn = htonl(lowest_tsn);
676
	retval = sctp_make_control(asoc, SCTP_CID_ECN_CWR, 0,
677
				   sizeof(cwr), GFP_ATOMIC);
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	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,
704
				  const __u32 lowest_tsn)
L
Linus Torvalds 已提交
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{
	struct sctp_chunk *retval;
707
	struct sctp_ecnehdr ecne;
L
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	ecne.lowest_tsn = htonl(lowest_tsn);
710
	retval = sctp_make_control(asoc, SCTP_CID_ECN_ECNE, 0,
711
				   sizeof(ecne), GFP_ATOMIC);
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	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,
725 726 727
					    const struct sctp_sndrcvinfo *sinfo,
					    int data_len, __u8 flags, __u16 ssn,
					    gfp_t gfp)
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{
	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.  */
741
	if (sinfo->sinfo_flags & SCTP_UNORDERED) {
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		flags |= SCTP_DATA_UNORDERED;
		dp.ssn = 0;
	} else
		dp.ssn = htons(ssn);

	chunk_len = sizeof(dp) + data_len;
748
	retval = sctp_make_data(asoc, flags, chunk_len, gfp);
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	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_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
766
	struct sctp_association *aptr = (struct sctp_association *)asoc;
767
	struct sctp_gap_ack_block gabs[SCTP_MAX_GABS];
768
	__u16 num_gabs, num_dup_tsns;
769
	struct sctp_transport *trans;
770 771 772 773
	struct sctp_chunk *retval;
	struct sctp_sackhdr sack;
	__u32 ctsn;
	int len;
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775
	memset(gabs, 0, sizeof(gabs));
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	ctsn = sctp_tsnmap_get_ctsn(map);
777 778

	pr_debug("%s: sackCTSNAck sent:0x%x\n", __func__, ctsn);
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	/* How much room is needed in the chunk? */
781
	num_gabs = sctp_tsnmap_num_gabs(map, gabs);
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	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.  */
795
	retval = sctp_make_control(asoc, SCTP_CID_SACK, 0, len, GFP_ATOMIC);
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	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,
837
				 gabs);
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	/* Add the duplicate TSN information.  */
840 841
	if (num_dup_tsns) {
		aptr->stats.idupchunks += num_dup_tsns;
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		sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns,
				 sctp_tsnmap_get_dups(map));
844
	}
845 846 847 848 849 850 851 852 853 854 855 856 857 858
	/* Once we have a sack generated, check to see what our sack
	 * generation is, if its 0, reset the transports to 0, and reset
	 * the association generation to 1
	 *
	 * The idea is that zero is never used as a valid generation for the
	 * association so no transport will match after a wrap event like this,
	 * Until the next sack
	 */
	if (++aptr->peer.sack_generation == 0) {
		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
				    transports)
			trans->sack_generation = 0;
		aptr->peer.sack_generation = 1;
	}
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nodata:
	return retval;
}

/* Make a SHUTDOWN chunk. */
struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
				      const struct sctp_chunk *chunk)
{
867
	struct sctp_shutdownhdr shut;
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	struct sctp_chunk *retval;
	__u32 ctsn;

	ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
	shut.cum_tsn_ack = htonl(ctsn);

874
	retval = sctp_make_control(asoc, SCTP_CID_SHUTDOWN, 0,
875
				   sizeof(shut), GFP_ATOMIC);
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	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,
889
					  const struct sctp_chunk *chunk)
L
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890 891 892
{
	struct sctp_chunk *retval;

893 894
	retval = sctp_make_control(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0,
				   GFP_ATOMIC);
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895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911

	/* 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(
912 913
					const struct sctp_association *asoc,
					const struct sctp_chunk *chunk)
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{
	struct sctp_chunk *retval;
	__u8 flags = 0;

918 919 920
	/* Set the T-bit if we have no association (vtag will be
	 * reflected)
	 */
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	flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T;

923 924
	retval = sctp_make_control(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags,
				   0, GFP_ATOMIC);
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	/* 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;

939
	return retval;
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}

/* Create an ABORT.  Note that we set the T bit if we have no
943
 * association, except when responding to an INIT (sctpimpguide 2.41).
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 */
struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
946 947
				   const struct sctp_chunk *chunk,
				   const size_t hint)
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{
	struct sctp_chunk *retval;
	__u8 flags = 0;

952 953 954 955 956 957 958 959 960 961
	/* Set the T-bit if we have no association and 'chunk' is not
	 * an INIT (vtag will be reflected).
	 */
	if (!asoc) {
		if (chunk && chunk->chunk_hdr &&
		    chunk->chunk_hdr->type == SCTP_CID_INIT)
			flags = 0;
		else
			flags = SCTP_CHUNK_FLAG_T;
	}
L
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963 964
	retval = sctp_make_control(asoc, SCTP_CID_ABORT, flags, hint,
				   GFP_ATOMIC);
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	/* 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(
983 984 985
					const struct sctp_association *asoc,
					const struct sctp_chunk *chunk,
					__u32 tsn)
L
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986 987
{
	struct sctp_chunk *retval;
A
Al Viro 已提交
988
	__be32 payload;
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990 991
	retval = sctp_make_abort(asoc, chunk,
				 sizeof(struct sctp_errhdr) + sizeof(tsn));
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	if (!retval)
		goto no_mem;

	/* Put the tsn back into network byte order.  */
	payload = htonl(tsn);
998 999
	sctp_init_cause(retval, SCTP_ERROR_NO_DATA, sizeof(payload));
	sctp_addto_chunk(retval, sizeof(payload), (const void *)&payload);
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	/* 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,
A
Al Viro 已提交
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					struct msghdr *msg,
1020
					size_t paylen)
L
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1021 1022
{
	struct sctp_chunk *retval;
1023 1024
	void *payload = NULL;
	int err;
L
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1026 1027
	retval = sctp_make_abort(asoc, NULL,
				 sizeof(struct sctp_errhdr) + paylen);
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1028 1029 1030 1031 1032
	if (!retval)
		goto err_chunk;

	if (paylen) {
		/* Put the msg_iov together into payload.  */
1033
		payload = kmalloc(paylen, GFP_KERNEL);
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1034 1035
		if (!payload)
			goto err_payload;
1036

A
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1037
		err = memcpy_from_msg(payload, msg, paylen);
1038 1039
		if (err < 0)
			goto err_copy;
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1040 1041
	}

1042 1043
	sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, paylen);
	sctp_addto_chunk(retval, paylen, payload);
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1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058

	if (paylen)
		kfree(payload);

	return retval;

err_copy:
	kfree(payload);
err_payload:
	sctp_chunk_free(retval);
	retval = NULL;
err_chunk:
	return retval;
}

1059 1060 1061 1062 1063 1064 1065
/* Append bytes to the end of a parameter.  Will panic if chunk is not big
 * enough.
 */
static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
			      const void *data)
{
	int chunklen = ntohs(chunk->chunk_hdr->length);
1066
	void *target;
1067 1068 1069

	target = skb_put(chunk->skb, len);

1070 1071 1072 1073
	if (data)
		memcpy(target, data, len);
	else
		memset(target, 0, len);
1074 1075 1076 1077 1078 1079 1080 1081

	/* Adjust the chunk length field.  */
	chunk->chunk_hdr->length = htons(chunklen + len);
	chunk->chunk_end = skb_tail_pointer(chunk->skb);

	return target;
}

1082
/* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */
L
Linus Torvalds 已提交
1083
struct sctp_chunk *sctp_make_abort_violation(
1084 1085 1086 1087
					const struct sctp_association *asoc,
					const struct sctp_chunk *chunk,
					const __u8 *payload,
					const size_t paylen)
L
Linus Torvalds 已提交
1088 1089 1090 1091
{
	struct sctp_chunk  *retval;
	struct sctp_paramhdr phdr;

1092 1093
	retval = sctp_make_abort(asoc, chunk, sizeof(struct sctp_errhdr) +
					      paylen + sizeof(phdr));
L
Linus Torvalds 已提交
1094 1095 1096
	if (!retval)
		goto end;

1097 1098
	sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, paylen +
							    sizeof(phdr));
L
Linus Torvalds 已提交
1099 1100 1101

	phdr.type = htons(chunk->chunk_hdr->type);
	phdr.length = chunk->chunk_hdr->length;
1102
	sctp_addto_chunk(retval, paylen, payload);
1103
	sctp_addto_param(retval, sizeof(phdr), &phdr);
L
Linus Torvalds 已提交
1104 1105 1106 1107 1108

end:
	return retval;
}

1109
struct sctp_chunk *sctp_make_violation_paramlen(
1110 1111 1112
					const struct sctp_association *asoc,
					const struct sctp_chunk *chunk,
					struct sctp_paramhdr *param)
1113 1114
{
	static const char error[] = "The following parameter had invalid length:";
1115
	size_t payload_len = sizeof(error) + sizeof(struct sctp_errhdr) +
1116
			     sizeof(*param);
1117
	struct sctp_chunk *retval;
1118 1119 1120 1121 1122 1123

	retval = sctp_make_abort(asoc, chunk, payload_len);
	if (!retval)
		goto nodata;

	sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION,
1124
			sizeof(error) + sizeof(*param));
1125
	sctp_addto_chunk(retval, sizeof(error), error);
1126
	sctp_addto_param(retval, sizeof(*param), param);
1127 1128 1129 1130 1131

nodata:
	return retval;
}

1132
struct sctp_chunk *sctp_make_violation_max_retrans(
1133 1134
					const struct sctp_association *asoc,
					const struct sctp_chunk *chunk)
1135 1136
{
	static const char error[] = "Association exceeded its max_retans count";
1137
	size_t payload_len = sizeof(error) + sizeof(struct sctp_errhdr);
1138
	struct sctp_chunk *retval;
1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150

	retval = sctp_make_abort(asoc, chunk, payload_len);
	if (!retval)
		goto nodata;

	sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, sizeof(error));
	sctp_addto_chunk(retval, sizeof(error), error);

nodata:
	return retval;
}

L
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1151 1152
/* Make a HEARTBEAT chunk.  */
struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
1153
				       const struct sctp_transport *transport)
L
Linus Torvalds 已提交
1154
{
1155
	struct sctp_sender_hb_info hbinfo;
1156 1157
	struct sctp_chunk *retval;

1158 1159
	retval = sctp_make_control(asoc, SCTP_CID_HEARTBEAT, 0,
				   sizeof(hbinfo), GFP_ATOMIC);
L
Linus Torvalds 已提交
1160 1161 1162 1163

	if (!retval)
		goto nodata;

1164
	hbinfo.param_hdr.type = SCTP_PARAM_HEARTBEAT_INFO;
1165
	hbinfo.param_hdr.length = htons(sizeof(hbinfo));
1166 1167 1168 1169
	hbinfo.daddr = transport->ipaddr;
	hbinfo.sent_at = jiffies;
	hbinfo.hb_nonce = transport->hb_nonce;

L
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1170 1171 1172 1173
	/* Cast away the 'const', as this is just telling the chunk
	 * what transport it belongs to.
	 */
	retval->transport = (struct sctp_transport *) transport;
1174 1175
	retval->subh.hbs_hdr = sctp_addto_chunk(retval, sizeof(hbinfo),
						&hbinfo);
L
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1176 1177 1178 1179 1180 1181

nodata:
	return retval;
}

struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
1182 1183 1184
					   const struct sctp_chunk *chunk,
					   const void *payload,
					   const size_t paylen)
L
Linus Torvalds 已提交
1185 1186 1187
{
	struct sctp_chunk *retval;

1188 1189
	retval  = sctp_make_control(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen,
				    GFP_ATOMIC);
L
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1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214
	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(
1215 1216 1217
					const struct sctp_association *asoc,
					const struct sctp_chunk *chunk,
					size_t size)
L
Linus Torvalds 已提交
1218 1219 1220
{
	struct sctp_chunk *retval;

1221
	retval = sctp_make_control(asoc, SCTP_CID_ERROR, 0,
1222 1223
				   sizeof(struct sctp_errhdr) + size,
				   GFP_ATOMIC);
L
Linus Torvalds 已提交
1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241
	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;
}

1242 1243 1244 1245
/* Create an Operation Error chunk of a fixed size,
 * specifically, max(asoc->pathmtu, SCTP_DEFAULT_MAXSEGMENT)
 * This is a helper function to allocate an error chunk for
 * for those invalid parameter codes in which we may not want
1246
 * to report all the errors, if the incoming chunk is large
1247 1248
 */
static inline struct sctp_chunk *sctp_make_op_error_fixed(
1249 1250
					const struct sctp_association *asoc,
					const struct sctp_chunk *chunk)
1251 1252 1253 1254 1255 1256 1257 1258 1259
{
	size_t size = asoc ? asoc->pathmtu : 0;

	if (!size)
		size = SCTP_DEFAULT_MAXSEGMENT;

	return sctp_make_op_error_space(asoc, chunk, size);
}

L
Linus Torvalds 已提交
1260 1261
/* Create an Operation Error chunk.  */
struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
1262 1263 1264
				      const struct sctp_chunk *chunk,
				      __be16 cause_code, const void *payload,
				      size_t paylen, size_t reserve_tail)
L
Linus Torvalds 已提交
1265 1266 1267
{
	struct sctp_chunk *retval;

1268
	retval = sctp_make_op_error_space(asoc, chunk, paylen + reserve_tail);
L
Linus Torvalds 已提交
1269 1270 1271
	if (!retval)
		goto nodata;

1272
	sctp_init_cause(retval, cause_code, paylen + reserve_tail);
1273
	sctp_addto_chunk(retval, paylen, payload);
1274 1275
	if (reserve_tail)
		sctp_addto_param(retval, reserve_tail, NULL);
L
Linus Torvalds 已提交
1276 1277 1278 1279 1280

nodata:
	return retval;
}

1281 1282 1283
struct sctp_chunk *sctp_make_auth(const struct sctp_association *asoc)
{
	struct sctp_authhdr auth_hdr;
1284 1285
	struct sctp_hmac *hmac_desc;
	struct sctp_chunk *retval;
1286 1287 1288 1289 1290 1291 1292
	__u8 *hmac;

	/* Get the first hmac that the peer told us to use */
	hmac_desc = sctp_auth_asoc_get_hmac(asoc);
	if (unlikely(!hmac_desc))
		return NULL;

1293
	retval = sctp_make_control(asoc, SCTP_CID_AUTH, 0,
1294 1295
				   hmac_desc->hmac_len + sizeof(auth_hdr),
				   GFP_ATOMIC);
1296 1297 1298 1299 1300 1301
	if (!retval)
		return NULL;

	auth_hdr.hmac_id = htons(hmac_desc->hmac_id);
	auth_hdr.shkey_id = htons(asoc->active_key_id);

1302 1303
	retval->subh.auth_hdr = sctp_addto_chunk(retval, sizeof(auth_hdr),
						 &auth_hdr);
1304

J
Johannes Berg 已提交
1305
	hmac = skb_put_zero(retval->skb, hmac_desc->hmac_len);
1306 1307 1308 1309 1310 1311 1312 1313 1314 1315

	/* Adjust the chunk header to include the empty MAC */
	retval->chunk_hdr->length =
		htons(ntohs(retval->chunk_hdr->length) + hmac_desc->hmac_len);
	retval->chunk_end = skb_tail_pointer(retval->skb);

	return retval;
}


L
Linus Torvalds 已提交
1316 1317 1318 1319 1320 1321
/********************************************************************
 * 2nd Level Abstractions
 ********************************************************************/

/* Turn an skb into a chunk.
 * FIXME: Eventually move the structure directly inside the skb->cb[].
1322 1323 1324 1325 1326 1327 1328
 *
 * 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.
 *
L
Linus Torvalds 已提交
1329 1330
 */
struct sctp_chunk *sctp_chunkify(struct sk_buff *skb,
1331 1332
				 const struct sctp_association *asoc,
				 struct sock *sk, gfp_t gfp)
L
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1333 1334 1335
{
	struct sctp_chunk *retval;

1336
	retval = kmem_cache_zalloc(sctp_chunk_cachep, gfp);
L
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1337 1338 1339

	if (!retval)
		goto nodata;
1340 1341
	if (!sk)
		pr_debug("%s: chunkifying skb:%p w/o an sk\n", __func__, skb);
L
Linus Torvalds 已提交
1342

1343
	INIT_LIST_HEAD(&retval->list);
L
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1344 1345 1346 1347
	retval->skb		= skb;
	retval->asoc		= (struct sctp_association *)asoc;
	retval->singleton	= 1;

1348
	retval->fast_retransmit = SCTP_CAN_FRTX;
L
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1349 1350 1351 1352 1353

	/* Polish the bead hole.  */
	INIT_LIST_HEAD(&retval->transmitted_list);
	INIT_LIST_HEAD(&retval->frag_list);
	SCTP_DBG_OBJCNT_INC(chunk);
1354
	refcount_set(&retval->refcnt, 1);
L
Linus Torvalds 已提交
1355 1356 1357 1358 1359 1360 1361 1362 1363

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)
{
1364
	memcpy(&chunk->source, src, sizeof(union sctp_addr));
1365
	memcpy(&chunk->dest, dest, sizeof(union sctp_addr));
L
Linus Torvalds 已提交
1366 1367 1368 1369 1370 1371 1372
}

/* 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) {
1373
		return &chunk->transport->ipaddr;
L
Linus Torvalds 已提交
1374 1375
	} else {
		/* Otherwise, extract it from the IP header.  */
1376
		return &chunk->source;
L
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1377 1378 1379 1380 1381 1382
	}
}

/* Create a new chunk, setting the type and flags headers from the
 * arguments, reserving enough space for a 'paylen' byte payload.
 */
1383
static struct sctp_chunk *_sctp_make_chunk(const struct sctp_association *asoc,
1384 1385
					   __u8 type, __u8 flags, int paylen,
					   gfp_t gfp)
L
Linus Torvalds 已提交
1386
{
1387
	struct sctp_chunkhdr *chunk_hdr;
1388
	struct sctp_chunk *retval;
L
Linus Torvalds 已提交
1389 1390 1391 1392
	struct sk_buff *skb;
	struct sock *sk;

	/* No need to allocate LL here, as this is only a chunk. */
1393
	skb = alloc_skb(SCTP_PAD4(sizeof(*chunk_hdr) + paylen), gfp);
L
Linus Torvalds 已提交
1394 1395 1396 1397
	if (!skb)
		goto nodata;

	/* Make room for the chunk header.  */
1398
	chunk_hdr = (struct sctp_chunkhdr *)skb_put(skb, sizeof(*chunk_hdr));
L
Linus Torvalds 已提交
1399 1400
	chunk_hdr->type	  = type;
	chunk_hdr->flags  = flags;
1401
	chunk_hdr->length = htons(sizeof(*chunk_hdr));
L
Linus Torvalds 已提交
1402 1403

	sk = asoc ? asoc->base.sk : NULL;
1404
	retval = sctp_chunkify(skb, asoc, sk, gfp);
L
Linus Torvalds 已提交
1405 1406 1407 1408 1409 1410
	if (!retval) {
		kfree_skb(skb);
		goto nodata;
	}

	retval->chunk_hdr = chunk_hdr;
1411
	retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(*chunk_hdr);
L
Linus Torvalds 已提交
1412

1413 1414 1415 1416
	/* Determine if the chunk needs to be authenticated */
	if (sctp_auth_send_cid(type, asoc))
		retval->auth = 1;

L
Linus Torvalds 已提交
1417 1418 1419 1420 1421
	return retval;
nodata:
	return NULL;
}

1422
static struct sctp_chunk *sctp_make_data(const struct sctp_association *asoc,
1423
					 __u8 flags, int paylen, gfp_t gfp)
1424
{
1425
	return _sctp_make_chunk(asoc, SCTP_CID_DATA, flags, paylen, gfp);
1426 1427 1428
}

static struct sctp_chunk *sctp_make_control(const struct sctp_association *asoc,
1429 1430
					    __u8 type, __u8 flags, int paylen,
					    gfp_t gfp)
1431
{
1432
	struct sctp_chunk *chunk;
1433

1434
	chunk = _sctp_make_chunk(asoc, type, flags, paylen, gfp);
1435 1436 1437 1438 1439
	if (chunk)
		sctp_control_set_owner_w(chunk);

	return chunk;
}
L
Linus Torvalds 已提交
1440 1441 1442 1443

/* Release the memory occupied by a chunk.  */
static void sctp_chunk_destroy(struct sctp_chunk *chunk)
{
1444 1445 1446
	BUG_ON(!list_empty(&chunk->list));
	list_del_init(&chunk->transmitted_list);

1447 1448
	consume_skb(chunk->skb);
	consume_skb(chunk->auth_chunk);
L
Linus Torvalds 已提交
1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466

	SCTP_DBG_OBJCNT_DEC(chunk);
	kmem_cache_free(sctp_chunk_cachep, chunk);
}

/* Possibly, free the chunk.  */
void sctp_chunk_free(struct sctp_chunk *chunk)
{
	/* 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)
{
1467
	refcount_inc(&ch->refcnt);
L
Linus Torvalds 已提交
1468 1469 1470 1471 1472
}

/* Release a reference to the chunk. */
void sctp_chunk_put(struct sctp_chunk *ch)
{
1473
	if (refcount_dec_and_test(&ch->refcnt))
L
Linus Torvalds 已提交
1474 1475 1476 1477 1478 1479 1480 1481 1482
		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)
{
	int chunklen = ntohs(chunk->chunk_hdr->length);
1483
	int padlen = SCTP_PAD4(chunklen) - chunklen;
1484
	void *target;
L
Linus Torvalds 已提交
1485

1486
	skb_put_zero(chunk->skb, padlen);
1487
	target = skb_put_data(chunk->skb, data, len);
L
Linus Torvalds 已提交
1488 1489 1490

	/* Adjust the chunk length field.  */
	chunk->chunk_hdr->length = htons(chunklen + padlen + len);
1491
	chunk->chunk_end = skb_tail_pointer(chunk->skb);
L
Linus Torvalds 已提交
1492 1493 1494 1495

	return target;
}

1496 1497 1498
/* Append bytes to the end of a chunk. Returns NULL if there isn't sufficient
 * space in the chunk
 */
1499 1500
static void *sctp_addto_chunk_fixed(struct sctp_chunk *chunk,
				    int len, const void *data)
1501
{
1502
	if (skb_tailroom(chunk->skb) >= len)
1503 1504 1505 1506 1507
		return sctp_addto_chunk(chunk, len, data);
	else
		return NULL;
}

L
Linus Torvalds 已提交
1508 1509 1510 1511
/* Append bytes from user space to the end of a chunk.  Will panic if
 * chunk is not big enough.
 * Returns a kernel err value.
 */
1512 1513
int sctp_user_addto_chunk(struct sctp_chunk *chunk, int len,
			  struct iov_iter *from)
L
Linus Torvalds 已提交
1514
{
1515
	void *target;
L
Linus Torvalds 已提交
1516 1517 1518 1519 1520

	/* Make room in chunk for data.  */
	target = skb_put(chunk->skb, len);

	/* Copy data (whole iovec) into chunk */
A
Al Viro 已提交
1521
	if (!copy_from_iter_full(target, len, from))
1522
		return -EFAULT;
L
Linus Torvalds 已提交
1523 1524 1525 1526

	/* Adjust the chunk length field.  */
	chunk->chunk_hdr->length =
		htons(ntohs(chunk->chunk_hdr->length) + len);
1527
	chunk->chunk_end = skb_tail_pointer(chunk->skb);
L
Linus Torvalds 已提交
1528

1529
	return 0;
L
Linus Torvalds 已提交
1530 1531 1532 1533 1534 1535 1536
}

/* 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)
{
1537
	struct sctp_stream *stream;
1538 1539 1540
	struct sctp_chunk *lchunk;
	struct sctp_datamsg *msg;
	__u16 ssn, sid;
L
Linus Torvalds 已提交
1541 1542 1543 1544

	if (chunk->has_ssn)
		return;

1545 1546
	/* All fragments will be on the same stream */
	sid = ntohs(chunk->subh.data_hdr->stream);
1547
	stream = &chunk->asoc->stream;
L
Linus Torvalds 已提交
1548

1549 1550 1551 1552 1553 1554 1555 1556 1557
	/* Now assign the sequence number to the entire message.
	 * All fragments must have the same stream sequence number.
	 */
	msg = chunk->msg;
	list_for_each_entry(lchunk, &msg->chunks, frag_list) {
		if (lchunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
			ssn = 0;
		} else {
			if (lchunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG)
1558
				ssn = sctp_ssn_next(stream, out, sid);
1559
			else
1560
				ssn = sctp_ssn_peek(stream, out, sid);
1561 1562 1563 1564 1565
		}

		lchunk->subh.data_hdr->ssn = htons(ssn);
		lchunk->has_ssn = 1;
	}
L
Linus Torvalds 已提交
1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584
}

/* 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,
1585 1586
					     struct sctp_chunk *chunk,
					     gfp_t gfp)
L
Linus Torvalds 已提交
1587 1588
{
	struct sctp_association *asoc;
X
Xin Long 已提交
1589
	enum sctp_scope scope;
L
Linus Torvalds 已提交
1590 1591 1592 1593 1594 1595 1596 1597 1598 1599
	struct sk_buff *skb;

	/* 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.  */
1600 1601
	SCTP_INPUT_CB(skb)->af->from_skb(&asoc->c.peer_addr, skb, 1);

L
Linus Torvalds 已提交
1602 1603 1604 1605 1606 1607 1608
nodata:
	return asoc;
}

/* Build a cookie representing asoc.
 * This INCLUDES the param header needed to put the cookie in the INIT ACK.
 */
1609 1610 1611 1612
static struct sctp_cookie_param *sctp_pack_cookie(
					const struct sctp_endpoint *ep,
					const struct sctp_association *asoc,
					const struct sctp_chunk *init_chunk,
1613 1614
					int *cookie_len, const __u8 *raw_addrs,
					int addrs_len)
L
Linus Torvalds 已提交
1615 1616
{
	struct sctp_signed_cookie *cookie;
1617
	struct sctp_cookie_param *retval;
L
Linus Torvalds 已提交
1618 1619
	int headersize, bodysize;

1620 1621 1622
	/* Header size is static data prior to the actual cookie, including
	 * any padding.
	 */
1623
	headersize = sizeof(struct sctp_paramhdr) +
1624
		     (sizeof(struct sctp_signed_cookie) -
1625
		      sizeof(struct sctp_cookie));
L
Linus Torvalds 已提交
1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639
	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;

	/* Clear this memory since we are sending this data structure
	 * out on the network.
	 */
1640 1641 1642 1643
	retval = kzalloc(*cookie_len, GFP_ATOMIC);
	if (!retval)
		goto nodata;

L
Linus Torvalds 已提交
1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657
	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;

1658 1659
	/* Save adaptation indication in the cookie. */
	cookie->c.adaptation_ind = asoc->peer.adaptation_ind;
L
Linus Torvalds 已提交
1660 1661

	/* Set an expiration time for the cookie.  */
1662
	cookie->c.expiration = ktime_add(asoc->cookie_life,
1663
					 ktime_get_real());
L
Linus Torvalds 已提交
1664 1665 1666 1667 1668 1669 1670 1671 1672

	/* 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);

1673
	if (sctp_sk(ep->base.sk)->hmac) {
H
Herbert Xu 已提交
1674 1675
		SHASH_DESC_ON_STACK(desc, sctp_sk(ep->base.sk)->hmac);
		int err;
1676

L
Linus Torvalds 已提交
1677
		/* Sign the message.  */
H
Herbert Xu 已提交
1678 1679 1680 1681 1682 1683 1684 1685 1686
		desc->tfm = sctp_sk(ep->base.sk)->hmac;
		desc->flags = 0;

		err = crypto_shash_setkey(desc->tfm, ep->secret_key,
					  sizeof(ep->secret_key)) ?:
		      crypto_shash_digest(desc, (u8 *)&cookie->c, bodysize,
					  cookie->signature);
		shash_desc_zero(desc);
		if (err)
1687
			goto free_cookie;
L
Linus Torvalds 已提交
1688 1689 1690
	}

	return retval;
1691 1692 1693 1694 1695 1696

free_cookie:
	kfree(retval);
nodata:
	*cookie_len = 0;
	return NULL;
L
Linus Torvalds 已提交
1697 1698 1699 1700
}

/* Unpack the cookie from COOKIE ECHO chunk, recreating the association.  */
struct sctp_association *sctp_unpack_cookie(
1701 1702 1703 1704
					const struct sctp_endpoint *ep,
					const struct sctp_association *asoc,
					struct sctp_chunk *chunk, gfp_t gfp,
					int *error, struct sctp_chunk **errp)
L
Linus Torvalds 已提交
1705 1706
{
	struct sctp_association *retval = NULL;
1707
	int headersize, bodysize, fixed_size;
L
Linus Torvalds 已提交
1708
	struct sctp_signed_cookie *cookie;
1709
	struct sk_buff *skb = chunk->skb;
L
Linus Torvalds 已提交
1710
	struct sctp_cookie *bear_cookie;
1711
	__u8 *digest = ep->digest;
X
Xin Long 已提交
1712
	enum sctp_scope scope;
1713
	unsigned int len;
1714
	ktime_t kt;
L
Linus Torvalds 已提交
1715

1716 1717 1718
	/* Header size is static data prior to the actual cookie, including
	 * any padding.
	 */
1719
	headersize = sizeof(struct sctp_chunkhdr) +
1720
		     (sizeof(struct sctp_signed_cookie) -
1721
		      sizeof(struct sctp_cookie));
L
Linus Torvalds 已提交
1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744
	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.  */
H
Herbert Xu 已提交
1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761
	{
		SHASH_DESC_ON_STACK(desc, sctp_sk(ep->base.sk)->hmac);
		int err;

		desc->tfm = sctp_sk(ep->base.sk)->hmac;
		desc->flags = 0;

		err = crypto_shash_setkey(desc->tfm, ep->secret_key,
					  sizeof(ep->secret_key)) ?:
		      crypto_shash_digest(desc, (u8 *)bear_cookie, bodysize,
					  digest);
		shash_desc_zero(desc);

		if (err) {
			*error = -SCTP_IERROR_NOMEM;
			goto fail;
		}
1762
	}
L
Linus Torvalds 已提交
1763 1764

	if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) {
1765 1766
		*error = -SCTP_IERROR_BAD_SIG;
		goto fail;
L
Linus Torvalds 已提交
1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781
	}

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;
	}

1782
	if (chunk->sctp_hdr->source != bear_cookie->peer_addr.v4.sin_port ||
L
Linus Torvalds 已提交
1783 1784 1785 1786 1787 1788 1789 1790
	    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.
1791 1792 1793 1794
	 * If skb has been timestamped, then use the stamp, otherwise
	 * use current time.  This introduces a small possibility that
	 * that a cookie may be considered expired, but his would only slow
	 * down the new association establishment instead of every packet.
L
Linus Torvalds 已提交
1795
	 */
1796
	if (sock_flag(ep->base.sk, SOCK_TIMESTAMP))
1797
		kt = skb_get_ktime(skb);
1798
	else
1799
		kt = ktime_get_real();
1800

1801
	if (!asoc && ktime_before(bear_cookie->expiration, kt)) {
L
Linus Torvalds 已提交
1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812
		/*
		 * 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) {
1813
			suseconds_t usecs = ktime_to_us(ktime_sub(kt, bear_cookie->expiration));
1814
			__be32 n = htonl(usecs);
L
Linus Torvalds 已提交
1815 1816

			sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE,
1817 1818
					sizeof(n));
			sctp_addto_chunk(*errp, sizeof(n), &n);
L
Linus Torvalds 已提交
1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847
			*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)) {
1848
		sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest,
1849 1850
				   sizeof(chunk->dest), SCTP_ADDR_SRC,
				   GFP_ATOMIC);
L
Linus Torvalds 已提交
1851 1852 1853 1854 1855
	}

	retval->next_tsn = retval->c.initial_tsn;
	retval->ctsn_ack_point = retval->next_tsn - 1;
	retval->addip_serial = retval->c.initial_tsn;
1856
	retval->strreset_outseq = retval->c.initial_tsn;
L
Linus Torvalds 已提交
1857 1858
	retval->adv_peer_ack_point = retval->ctsn_ack_point;
	retval->peer.prsctp_capable = retval->c.prsctp_capable;
1859
	retval->peer.adaptation_ind = retval->c.adaptation_ind;
L
Linus Torvalds 已提交
1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882

	/* 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 {
A
Al Viro 已提交
1883 1884
	__be32 num_missing;
	__be16 type;
E
Eric Dumazet 已提交
1885
}  __packed;
L
Linus Torvalds 已提交
1886 1887 1888 1889 1890

/*
 * Report a missing mandatory parameter.
 */
static int sctp_process_missing_param(const struct sctp_association *asoc,
X
Xin Long 已提交
1891
				      enum sctp_param paramtype,
L
Linus Torvalds 已提交
1892 1893 1894 1895 1896 1897
				      struct sctp_chunk *chunk,
				      struct sctp_chunk **errp)
{
	struct __sctp_missing report;
	__u16 len;

1898
	len = SCTP_PAD4(sizeof(report));
L
Linus Torvalds 已提交
1899 1900 1901 1902 1903 1904 1905 1906 1907 1908

	/* 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;
1909
		sctp_init_cause(*errp, SCTP_ERROR_MISS_PARAM,
1910 1911
				sizeof(report));
		sctp_addto_chunk(*errp, sizeof(report), &report);
L
Linus Torvalds 已提交
1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928
	}

	/* 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)
1929
		sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, 0);
L
Linus Torvalds 已提交
1930 1931 1932 1933 1934 1935 1936 1937 1938 1939

	/* 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)
{
1940 1941 1942 1943 1944 1945
	/* This is a fatal error.  Any accumulated non-fatal errors are
	 * not reported.
	 */
	if (*errp)
		sctp_chunk_free(*errp);

L
Linus Torvalds 已提交
1946
	/* Create an error chunk and fill it in with our payload. */
1947
	*errp = sctp_make_violation_paramlen(asoc, chunk, param);
L
Linus Torvalds 已提交
1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962

	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);

1963 1964 1965 1966 1967 1968 1969 1970 1971
	/* Processing of the HOST_NAME parameter will generate an
	 * ABORT.  If we've accumulated any non-fatal errors, they
	 * would be unrecognized parameters and we should not include
	 * them in the ABORT.
	 */
	if (*errp)
		sctp_chunk_free(*errp);

	*errp = sctp_make_op_error_space(asoc, chunk, len);
L
Linus Torvalds 已提交
1972

1973 1974 1975 1976
	if (*errp) {
		sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED, len);
		sctp_addto_chunk(*errp, len, param.v);
	}
L
Linus Torvalds 已提交
1977 1978 1979 1980 1981

	/* Stop processing this chunk. */
	return 0;
}

1982
static int sctp_verify_ext_param(struct net *net, union sctp_params param)
1983
{
1984
	__u16 num_ext = ntohs(param.p->length) - sizeof(struct sctp_paramhdr);
1985
	int have_asconf = 0;
1986
	int have_auth = 0;
1987 1988 1989 1990
	int i;

	for (i = 0; i < num_ext; i++) {
		switch (param.ext->chunks[i]) {
1991 1992 1993 1994 1995 1996 1997
		case SCTP_CID_AUTH:
			have_auth = 1;
			break;
		case SCTP_CID_ASCONF:
		case SCTP_CID_ASCONF_ACK:
			have_asconf = 1;
			break;
1998 1999 2000 2001 2002 2003 2004 2005
		}
	}

	/* ADD-IP Security: The draft requires us to ABORT or ignore the
	 * INIT/INIT-ACK if ADD-IP is listed, but AUTH is not.  Do this
	 * only if ADD-IP is turned on and we are not backward-compatible
	 * mode.
	 */
2006
	if (net->sctp.addip_noauth)
2007 2008
		return 1;

2009
	if (net->sctp.addip_enable && !have_auth && have_asconf)
2010 2011 2012 2013 2014
		return 0;

	return 1;
}

2015
static void sctp_process_ext_param(struct sctp_association *asoc,
2016
				   union sctp_params param)
2017
{
2018
	__u16 num_ext = ntohs(param.p->length) - sizeof(struct sctp_paramhdr);
2019
	struct net *net = sock_net(asoc->base.sk);
2020 2021 2022 2023
	int i;

	for (i = 0; i < num_ext; i++) {
		switch (param.ext->chunks[i]) {
2024 2025 2026 2027 2028
		case SCTP_CID_RECONF:
			if (asoc->reconf_enable &&
			    !asoc->peer.reconf_capable)
				asoc->peer.reconf_capable = 1;
			break;
2029
		case SCTP_CID_FWD_TSN:
2030 2031
			if (asoc->prsctp_enable && !asoc->peer.prsctp_capable)
				asoc->peer.prsctp_capable = 1;
2032 2033 2034 2035 2036
			break;
		case SCTP_CID_AUTH:
			/* if the peer reports AUTH, assume that he
			 * supports AUTH.
			 */
2037
			if (asoc->ep->auth_enable)
2038 2039 2040 2041 2042 2043 2044
				asoc->peer.auth_capable = 1;
			break;
		case SCTP_CID_ASCONF:
		case SCTP_CID_ASCONF_ACK:
			if (net->sctp.addip_enable)
				asoc->peer.asconf_capable = 1;
			break;
2045 2046 2047 2048
		case SCTP_CID_I_DATA:
			if (sctp_sk(asoc->base.sk)->strm_interleave)
				asoc->intl_enable = 1;
			break;
2049 2050
		default:
			break;
2051 2052 2053 2054
		}
	}
}

L
Linus Torvalds 已提交
2055 2056 2057 2058 2059 2060 2061
/* 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.
 *
2062 2063
 * 00 - Stop processing this parameter; do not process any further
 * 	parameters within this chunk
L
Linus Torvalds 已提交
2064
 *
2065 2066 2067
 * 01 - Stop processing this parameter, do not process any further
 *	parameters within this chunk, and report the unrecognized
 *	parameter in an 'Unrecognized Parameter' ERROR chunk.
L
Linus Torvalds 已提交
2068 2069 2070 2071 2072
 *
 * 10 - Skip this parameter and continue processing.
 *
 * 11 - Skip this parameter and continue processing but
 *	report the unrecognized parameter in an
2073
 *	'Unrecognized Parameter' ERROR chunk.
L
Linus Torvalds 已提交
2074 2075
 *
 * Return value:
2076 2077 2078
 * 	SCTP_IERROR_NO_ERROR - continue with the chunk
 * 	SCTP_IERROR_ERROR    - stop and report an error.
 * 	SCTP_IERROR_NOMEME   - out of memory.
L
Linus Torvalds 已提交
2079
 */
2080 2081 2082 2083 2084
static enum sctp_ierror sctp_process_unk_param(
					const struct sctp_association *asoc,
					union sctp_params param,
					struct sctp_chunk *chunk,
					struct sctp_chunk **errp)
L
Linus Torvalds 已提交
2085
{
2086
	int retval = SCTP_IERROR_NO_ERROR;
L
Linus Torvalds 已提交
2087 2088 2089

	switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
	case SCTP_PARAM_ACTION_DISCARD:
2090
		retval =  SCTP_IERROR_ERROR;
L
Linus Torvalds 已提交
2091 2092 2093
		break;
	case SCTP_PARAM_ACTION_SKIP:
		break;
2094 2095 2096
	case SCTP_PARAM_ACTION_DISCARD_ERR:
		retval =  SCTP_IERROR_ERROR;
		/* Fall through */
L
Linus Torvalds 已提交
2097 2098 2099 2100 2101
	case SCTP_PARAM_ACTION_SKIP_ERR:
		/* Make an ERROR chunk, preparing enough room for
		 * returning multiple unknown parameters.
		 */
		if (NULL == *errp)
2102
			*errp = sctp_make_op_error_fixed(asoc, chunk);
L
Linus Torvalds 已提交
2103 2104

		if (*errp) {
2105
			if (!sctp_init_cause_fixed(*errp, SCTP_ERROR_UNKNOWN_PARAM,
2106
					SCTP_PAD4(ntohs(param.p->length))))
2107
				sctp_addto_chunk_fixed(*errp,
2108
						SCTP_PAD4(ntohs(param.p->length)),
2109
						param.v);
L
Linus Torvalds 已提交
2110 2111 2112 2113 2114 2115
		} 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.
			 */
2116
			retval = SCTP_IERROR_NOMEM;
L
Linus Torvalds 已提交
2117 2118 2119 2120 2121 2122 2123 2124 2125
		}
		break;
	default:
		break;
	}

	return retval;
}

2126
/* Verify variable length parameters
L
Linus Torvalds 已提交
2127
 * Return values:
2128 2129 2130 2131
 * 	SCTP_IERROR_ABORT - trigger an ABORT
 * 	SCTP_IERROR_NOMEM - out of memory (abort)
 *	SCTP_IERROR_ERROR - stop processing, trigger an ERROR
 * 	SCTP_IERROR_NO_ERROR - continue with the chunk
L
Linus Torvalds 已提交
2132
 */
2133 2134 2135 2136 2137 2138 2139
static enum sctp_ierror sctp_verify_param(struct net *net,
					  const struct sctp_endpoint *ep,
					  const struct sctp_association *asoc,
					  union sctp_params param,
					  enum sctp_cid cid,
					  struct sctp_chunk *chunk,
					  struct sctp_chunk **err_chunk)
L
Linus Torvalds 已提交
2140
{
2141
	struct sctp_hmac_algo_param *hmacs;
2142
	int retval = SCTP_IERROR_NO_ERROR;
2143 2144
	__u16 n_elt, id = 0;
	int i;
L
Linus Torvalds 已提交
2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159

	/* 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:
2160
	case SCTP_PARAM_ADAPTATION_LAYER_IND:
2161 2162
		break;

2163
	case SCTP_PARAM_SUPPORTED_EXT:
2164
		if (!sctp_verify_ext_param(net, param))
2165
			return SCTP_IERROR_ABORT;
L
Linus Torvalds 已提交
2166 2167
		break;

2168
	case SCTP_PARAM_SET_PRIMARY:
2169
		if (net->sctp.addip_enable)
2170 2171 2172
			break;
		goto fallthrough;

L
Linus Torvalds 已提交
2173 2174
	case SCTP_PARAM_HOST_NAME_ADDRESS:
		/* Tell the peer, we won't support this param.  */
2175 2176 2177
		sctp_process_hn_param(asoc, param, chunk, err_chunk);
		retval = SCTP_IERROR_ABORT;
		break;
2178

L
Linus Torvalds 已提交
2179
	case SCTP_PARAM_FWD_TSN_SUPPORT:
2180
		if (ep->prsctp_enable)
L
Linus Torvalds 已提交
2181
			break;
2182 2183 2184
		goto fallthrough;

	case SCTP_PARAM_RANDOM:
2185
		if (!ep->auth_enable)
2186 2187 2188 2189 2190 2191 2192 2193
			goto fallthrough;

		/* SCTP-AUTH: Secion 6.1
		 * If the random number is not 32 byte long the association
		 * MUST be aborted.  The ABORT chunk SHOULD contain the error
		 * cause 'Protocol Violation'.
		 */
		if (SCTP_AUTH_RANDOM_LENGTH !=
2194
			ntohs(param.p->length) - sizeof(struct sctp_paramhdr)) {
2195
			sctp_process_inv_paramlength(asoc, param.p,
2196
							chunk, err_chunk);
2197 2198
			retval = SCTP_IERROR_ABORT;
		}
2199 2200 2201
		break;

	case SCTP_PARAM_CHUNKS:
2202
		if (!ep->auth_enable)
2203 2204 2205 2206 2207 2208 2209
			goto fallthrough;

		/* SCTP-AUTH: Section 3.2
		 * The CHUNKS parameter MUST be included once in the INIT or
		 *  INIT-ACK chunk if the sender wants to receive authenticated
		 *  chunks.  Its maximum length is 260 bytes.
		 */
2210 2211 2212 2213 2214
		if (260 < ntohs(param.p->length)) {
			sctp_process_inv_paramlength(asoc, param.p,
						     chunk, err_chunk);
			retval = SCTP_IERROR_ABORT;
		}
2215 2216 2217
		break;

	case SCTP_PARAM_HMAC_ALGO:
2218
		if (!ep->auth_enable)
2219 2220 2221
			goto fallthrough;

		hmacs = (struct sctp_hmac_algo_param *)param.p;
2222 2223
		n_elt = (ntohs(param.p->length) -
			 sizeof(struct sctp_paramhdr)) >> 1;
2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241

		/* SCTP-AUTH: Section 6.1
		 * The HMAC algorithm based on SHA-1 MUST be supported and
		 * included in the HMAC-ALGO parameter.
		 */
		for (i = 0; i < n_elt; i++) {
			id = ntohs(hmacs->hmac_ids[i]);

			if (id == SCTP_AUTH_HMAC_ID_SHA1)
				break;
		}

		if (id != SCTP_AUTH_HMAC_ID_SHA1) {
			sctp_process_inv_paramlength(asoc, param.p, chunk,
						     err_chunk);
			retval = SCTP_IERROR_ABORT;
		}
		break;
2242
fallthrough:
L
Linus Torvalds 已提交
2243
	default:
2244 2245 2246
		pr_debug("%s: unrecognized param:%d for chunk:%d\n",
			 __func__, ntohs(param.p->type), cid);

2247
		retval = sctp_process_unk_param(asoc, param, chunk, err_chunk);
L
Linus Torvalds 已提交
2248 2249 2250 2251 2252 2253
		break;
	}
	return retval;
}

/* Verify the INIT packet before we process it.  */
2254
int sctp_verify_init(struct net *net, const struct sctp_endpoint *ep,
X
Xin Long 已提交
2255
		     const struct sctp_association *asoc, enum sctp_cid cid,
2256 2257
		     struct sctp_init_chunk *peer_init,
		     struct sctp_chunk *chunk, struct sctp_chunk **errp)
L
Linus Torvalds 已提交
2258 2259
{
	union sctp_params param;
2260
	bool has_cookie = false;
2261
	int result;
L
Linus Torvalds 已提交
2262

2263 2264 2265 2266 2267 2268 2269 2270
	/* Check for missing mandatory parameters. Note: Initial TSN is
	 * also mandatory, but is not checked here since the valid range
	 * is 0..2**32-1. RFC4960, section 3.3.3.
	 */
	if (peer_init->init_hdr.num_outbound_streams == 0 ||
	    peer_init->init_hdr.num_inbound_streams == 0 ||
	    peer_init->init_hdr.init_tag == 0 ||
	    ntohl(peer_init->init_hdr.a_rwnd) < SCTP_DEFAULT_MINWINDOW)
2271
		return sctp_process_inv_mandatory(asoc, chunk, errp);
L
Linus Torvalds 已提交
2272 2273

	sctp_walk_params(param, peer_init, init_hdr.params) {
2274 2275 2276
		if (param.p->type == SCTP_PARAM_STATE_COOKIE)
			has_cookie = true;
	}
L
Linus Torvalds 已提交
2277 2278 2279 2280 2281 2282 2283 2284

	/* 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.
	 */
2285
	if (param.v != (void *)chunk->chunk_end)
2286
		return sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
L
Linus Torvalds 已提交
2287 2288 2289 2290

	/* The only missing mandatory param possible today is
	 * the state cookie for an INIT-ACK chunk.
	 */
2291 2292 2293
	if ((SCTP_CID_INIT_ACK == cid) && !has_cookie)
		return sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
						  chunk, errp);
L
Linus Torvalds 已提交
2294

2295
	/* Verify all the variable length parameters */
L
Linus Torvalds 已提交
2296
	sctp_walk_params(param, peer_init, init_hdr.params) {
2297 2298
		result = sctp_verify_param(net, ep, asoc, param, cid,
					   chunk, errp);
2299
		switch (result) {
2300 2301 2302 2303 2304 2305 2306 2307
		case SCTP_IERROR_ABORT:
		case SCTP_IERROR_NOMEM:
			return 0;
		case SCTP_IERROR_ERROR:
			return 1;
		case SCTP_IERROR_NO_ERROR:
		default:
			break;
L
Linus Torvalds 已提交
2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318
		}

	} /* 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.
 */
2319
int sctp_process_init(struct sctp_association *asoc, struct sctp_chunk *chunk,
L
Linus Torvalds 已提交
2320
		      const union sctp_addr *peer_addr,
2321
		      struct sctp_init_chunk *peer_init, gfp_t gfp)
L
Linus Torvalds 已提交
2322
{
2323
	struct net *net = sock_net(asoc->base.sk);
L
Linus Torvalds 已提交
2324 2325
	struct sctp_transport *transport;
	struct list_head *pos, *temp;
2326
	union sctp_params param;
2327
	union sctp_addr addr;
2328
	struct sctp_af *af;
2329
	int src_match = 0;
2330
	char *cookie;
L
Linus Torvalds 已提交
2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341

	/* 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.
	 */
2342
	if (!sctp_assoc_add_peer(asoc, peer_addr, gfp, SCTP_ACTIVE))
2343 2344 2345 2346
		goto nomem;

	if (sctp_cmp_addr_exact(sctp_source(chunk), peer_addr))
		src_match = 1;
L
Linus Torvalds 已提交
2347 2348 2349

	/* Process the initialization parameters.  */
	sctp_walk_params(param, peer_init, init_hdr.params) {
2350 2351 2352 2353 2354 2355 2356 2357
		if (!src_match && (param.p->type == SCTP_PARAM_IPV4_ADDRESS ||
		    param.p->type == SCTP_PARAM_IPV6_ADDRESS)) {
			af = sctp_get_af_specific(param_type2af(param.p->type));
			af->from_addr_param(&addr, param.addr,
					    chunk->sctp_hdr->source, 0);
			if (sctp_cmp_addr_exact(sctp_source(chunk), &addr))
				src_match = 1;
		}
L
Linus Torvalds 已提交
2358 2359

		if (!sctp_process_param(asoc, param, peer_addr, gfp))
2360
			goto clean_up;
L
Linus Torvalds 已提交
2361 2362
	}

2363 2364 2365 2366
	/* source address of chunk may not match any valid address */
	if (!src_match)
		goto clean_up;

2367 2368 2369 2370 2371 2372 2373
	/* AUTH: After processing the parameters, make sure that we
	 * have all the required info to potentially do authentications.
	 */
	if (asoc->peer.auth_capable && (!asoc->peer.peer_random ||
					!asoc->peer.peer_hmacs))
		asoc->peer.auth_capable = 0;

2374 2375 2376 2377 2378
	/* In a non-backward compatible mode, if the peer claims
	 * support for ADD-IP but not AUTH,  the ADD-IP spec states
	 * that we MUST ABORT the association. Section 6.  The section
	 * also give us an option to silently ignore the packet, which
	 * is what we'll do here.
2379
	 */
2380
	if (!net->sctp.addip_noauth &&
2381
	     (asoc->peer.asconf_capable && !asoc->peer.auth_capable)) {
2382 2383 2384
		asoc->peer.addip_disabled_mask |= (SCTP_PARAM_ADD_IP |
						  SCTP_PARAM_DEL_IP |
						  SCTP_PARAM_SET_PRIMARY);
2385
		asoc->peer.asconf_capable = 0;
2386
		goto clean_up;
2387 2388
	}

F
Frank Filz 已提交
2389 2390 2391 2392 2393 2394 2395 2396
	/* Walk list of transports, removing transports in the UNKNOWN state. */
	list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
		transport = list_entry(pos, struct sctp_transport, transports);
		if (transport->state == SCTP_UNKNOWN) {
			sctp_assoc_rm_peer(asoc, transport);
		}
	}

L
Linus Torvalds 已提交
2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410
	/* 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);

2411 2412
	asoc->strreset_inseq = asoc->peer.i.initial_tsn;

L
Linus Torvalds 已提交
2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436
	/* 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) {
2437
		asoc->peer.cookie = kmemdup(cookie, asoc->peer.cookie_len, gfp);
L
Linus Torvalds 已提交
2438 2439 2440 2441 2442 2443 2444 2445
		if (!asoc->peer.cookie)
			goto clean_up;
	}

	/* 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).
	 */
2446 2447
	list_for_each_entry(transport, &asoc->peer.transport_addr_list,
			transports) {
L
Linus Torvalds 已提交
2448 2449 2450 2451
		transport->ssthresh = asoc->peer.i.a_rwnd;
	}

	/* Set up the TSN tracking pieces.  */
2452 2453 2454
	if (!sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_INITIAL,
				asoc->peer.i.initial_tsn, gfp))
		goto clean_up;
L
Linus Torvalds 已提交
2455 2456 2457 2458 2459 2460 2461 2462 2463

	/* 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.
	 */

2464 2465
	if (sctp_stream_init(&asoc->stream, asoc->c.sinit_num_ostreams,
			     asoc->c.sinit_max_instreams, gfp))
2466
		goto clean_up;
L
Linus Torvalds 已提交
2467

2468 2469
	if (!asoc->temp && sctp_assoc_set_id(asoc, gfp))
		goto clean_up;
L
Linus Torvalds 已提交
2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 2487

	/* 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);
2488 2489
		if (transport->state != SCTP_ACTIVE)
			sctp_assoc_rm_peer(asoc, transport);
L
Linus Torvalds 已提交
2490
	}
F
Frank Filz 已提交
2491

L
Linus Torvalds 已提交
2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510
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,
A
Al Viro 已提交
2511
			      gfp_t gfp)
L
Linus Torvalds 已提交
2512
{
2513
	struct net *net = sock_net(asoc->base.sk);
2514
	struct sctp_endpoint *ep = asoc->ep;
2515 2516
	union sctp_addr_param *addr_param;
	struct sctp_transport *t;
2517 2518 2519 2520 2521 2522
	enum sctp_scope scope;
	union sctp_addr addr;
	struct sctp_af *af;
	int retval = 1, i;
	u32 stale;
	__u16 sat;
L
Linus Torvalds 已提交
2523 2524 2525 2526 2527 2528 2529 2530 2531

	/* 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;
2532 2533
		goto do_addr_param;

L
Linus Torvalds 已提交
2534
	case SCTP_PARAM_IPV4_ADDRESS:
2535 2536 2537 2538
		/* v4 addresses are not allowed on v6-only socket */
		if (ipv6_only_sock(asoc->base.sk))
			break;
do_addr_param:
L
Linus Torvalds 已提交
2539
		af = sctp_get_af_specific(param_type2af(param.p->type));
2540
		af->from_addr_param(&addr, param.addr, htons(asoc->peer.port), 0);
L
Linus Torvalds 已提交
2541
		scope = sctp_scope(peer_addr);
2542
		if (sctp_in_scope(net, &addr, scope))
2543
			if (!sctp_assoc_add_peer(asoc, &addr, gfp, SCTP_UNCONFIRMED))
L
Linus Torvalds 已提交
2544 2545 2546 2547
				return 0;
		break;

	case SCTP_PARAM_COOKIE_PRESERVATIVE:
2548
		if (!net->sctp.cookie_preserve_enable)
L
Linus Torvalds 已提交
2549 2550 2551 2552 2553 2554 2555
			break;

		stale = ntohl(param.life->lifespan_increment);

		/* Suggested Cookie Life span increment's unit is msec,
		 * (1/1000sec).
		 */
2556
		asoc->cookie_life = ktime_add_ms(asoc->cookie_life, stale);
L
Linus Torvalds 已提交
2557 2558 2559
		break;

	case SCTP_PARAM_HOST_NAME_ADDRESS:
2560
		pr_debug("%s: unimplemented SCTP_HOST_NAME_ADDRESS\n", __func__);
L
Linus Torvalds 已提交
2561 2562 2563 2564 2565 2566 2567 2568 2569
		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;

2570 2571 2572 2573 2574 2575 2576 2577
		/* Assume that peer supports the address family
		 * by which it sends a packet.
		 */
		if (peer_addr->sa.sa_family == AF_INET6)
			asoc->peer.ipv6_address = 1;
		else if (peer_addr->sa.sa_family == AF_INET)
			asoc->peer.ipv4_address = 1;

L
Linus Torvalds 已提交
2578
		/* Cycle through address types; avoid divide by 0. */
2579
		sat = ntohs(param.p->length) - sizeof(struct sctp_paramhdr);
L
Linus Torvalds 已提交
2580 2581 2582 2583 2584 2585 2586 2587 2588 2589
		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:
2590 2591
				if (PF_INET6 == asoc->base.sk->sk_family)
					asoc->peer.ipv6_address = 1;
L
Linus Torvalds 已提交
2592 2593 2594 2595 2596 2597 2598 2599
				break;

			case SCTP_PARAM_HOST_NAME_ADDRESS:
				asoc->peer.hostname_address = 1;
				break;

			default: /* Just ignore anything else.  */
				break;
2600
			}
L
Linus Torvalds 已提交
2601 2602 2603 2604 2605
		}
		break;

	case SCTP_PARAM_STATE_COOKIE:
		asoc->peer.cookie_len =
2606
			ntohs(param.p->length) - sizeof(struct sctp_paramhdr);
L
Linus Torvalds 已提交
2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621
		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;

2622
	case SCTP_PARAM_ADAPTATION_LAYER_IND:
2623
		asoc->peer.adaptation_ind = ntohl(param.aind->adaptation_ind);
L
Linus Torvalds 已提交
2624 2625
		break;

2626
	case SCTP_PARAM_SET_PRIMARY:
2627
		if (!net->sctp.addip_enable)
2628 2629
			goto fall_through;

2630
		addr_param = param.v + sizeof(struct sctp_addip_param);
2631

2632
		af = sctp_get_af_specific(param_type2af(addr_param->p.type));
2633 2634 2635
		if (af == NULL)
			break;

2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651
		af->from_addr_param(&addr, addr_param,
				    htons(asoc->peer.port), 0);

		/* if the address is invalid, we can't process it.
		 * XXX: see spec for what to do.
		 */
		if (!af->addr_valid(&addr, NULL, NULL))
			break;

		t = sctp_assoc_lookup_paddr(asoc, &addr);
		if (!t)
			break;

		sctp_assoc_set_primary(asoc, t);
		break;

2652 2653 2654 2655
	case SCTP_PARAM_SUPPORTED_EXT:
		sctp_process_ext_param(asoc, param);
		break;

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	case SCTP_PARAM_FWD_TSN_SUPPORT:
2657
		if (asoc->prsctp_enable) {
L
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			asoc->peer.prsctp_capable = 1;
			break;
		}
2661
		/* Fall Through */
2662 2663 2664
		goto fall_through;

	case SCTP_PARAM_RANDOM:
2665
		if (!ep->auth_enable)
2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677
			goto fall_through;

		/* Save peer's random parameter */
		asoc->peer.peer_random = kmemdup(param.p,
					    ntohs(param.p->length), gfp);
		if (!asoc->peer.peer_random) {
			retval = 0;
			break;
		}
		break;

	case SCTP_PARAM_HMAC_ALGO:
2678
		if (!ep->auth_enable)
2679 2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693
			goto fall_through;

		/* Save peer's HMAC list */
		asoc->peer.peer_hmacs = kmemdup(param.p,
					    ntohs(param.p->length), gfp);
		if (!asoc->peer.peer_hmacs) {
			retval = 0;
			break;
		}

		/* Set the default HMAC the peer requested*/
		sctp_auth_asoc_set_default_hmac(asoc, param.hmac_algo);
		break;

	case SCTP_PARAM_CHUNKS:
2694
		if (!ep->auth_enable)
2695 2696 2697 2698 2699 2700 2701 2702
			goto fall_through;

		asoc->peer.peer_chunks = kmemdup(param.p,
					    ntohs(param.p->length), gfp);
		if (!asoc->peer.peer_chunks)
			retval = 0;
		break;
fall_through:
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	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.
		 */
2709 2710
		pr_debug("%s: ignoring param:%d for association:%p.\n",
			 __func__, ntohs(param.p->type), asoc);
L
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2711
		break;
2712
	}
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	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                       |
 *      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
2761
 * Address Parameter and other parameter will not be wrapped in this function
L
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 */
static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc,
					   union sctp_addr *addr,
					   int vparam_len)
{
2767
	struct sctp_addiphdr asconf;
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	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.  */
2780 2781
	retval = sctp_make_control(asoc, SCTP_CID_ASCONF, 0, length,
				   GFP_ATOMIC);
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	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,
2820 2821 2822
					      union sctp_addr *laddr,
					      struct sockaddr *addrs,
					      int addrcnt, __be16 flags)
L
Linus Torvalds 已提交
2823
{
2824
	union sctp_addr_param addr_param;
2825
	struct sctp_addip_param	param;
2826 2827 2828 2829 2830 2831 2832 2833
	int paramlen = sizeof(param);
	struct sctp_chunk *retval;
	int addr_param_len = 0;
	union sctp_addr *addr;
	int totallen = 0, i;
	int del_pickup = 0;
	struct sctp_af *af;
	void *addr_buf;
L
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2834 2835 2836 2837

	/* Get total length of all the address parameters. */
	addr_buf = addrs;
	for (i = 0; i < addrcnt; i++) {
J
Joe Perches 已提交
2838
		addr = addr_buf;
L
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2839 2840 2841 2842 2843 2844 2845
		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;
2846 2847 2848 2849 2850
		if (asoc->asconf_addr_del_pending && !del_pickup) {
			/* reuse the parameter length from the same scope one */
			totallen += paramlen;
			totallen += addr_param_len;
			del_pickup = 1;
2851 2852 2853 2854

			pr_debug("%s: picked same-scope del_pending addr, "
				 "totallen for all addresses is %d\n",
				 __func__, totallen);
2855
		}
L
Linus Torvalds 已提交
2856 2857 2858 2859 2860 2861 2862 2863 2864 2865
	}

	/* 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++) {
J
Joe Perches 已提交
2866
		addr = addr_buf;
L
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2867 2868 2869 2870
		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);
2871
		param.crr_id = htonl(i);
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2872 2873 2874 2875 2876 2877

		sctp_addto_chunk(retval, paramlen, &param);
		sctp_addto_chunk(retval, addr_param_len, &addr_param);

		addr_buf += af->sockaddr_len;
	}
2878 2879 2880 2881 2882 2883
	if (flags == SCTP_PARAM_ADD_IP && del_pickup) {
		addr = asoc->asconf_addr_del_pending;
		af = sctp_get_af_specific(addr->v4.sin_family);
		addr_param_len = af->to_addr_param(addr, &addr_param);
		param.param_hdr.type = SCTP_PARAM_DEL_IP;
		param.param_hdr.length = htons(paramlen + addr_param_len);
2884
		param.crr_id = htonl(i);
2885 2886 2887 2888

		sctp_addto_chunk(retval, paramlen, &param);
		sctp_addto_chunk(retval, addr_param_len, &addr_param);
	}
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2889 2890 2891 2892 2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903
	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                       |
 *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
2904
 * Create an ASCONF chunk with Set Primary IP address parameter.
L
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2905 2906 2907 2908
 */
struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
					     union sctp_addr *addr)
{
2909 2910
	struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family);
	union sctp_addr_param addrparam;
2911
	struct sctp_addip_param	param;
2912 2913 2914
	struct sctp_chunk *retval;
	int len = sizeof(param);
	int addrlen;
L
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2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944 2945 2946 2947 2948 2949 2950 2951 2952

	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                   |
 *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
2953
 * Create an ASCONF_ACK chunk with enough space for the parameter responses.
L
Linus Torvalds 已提交
2954 2955 2956 2957
 */
static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc,
					       __u32 serial, int vparam_len)
{
2958 2959 2960
	struct sctp_addiphdr asconf;
	struct sctp_chunk *retval;
	int length = sizeof(asconf) + vparam_len;
L
Linus Torvalds 已提交
2961 2962

	/* Create the chunk.  */
2963 2964
	retval = sctp_make_control(asoc, SCTP_CID_ASCONF_ACK, 0, length,
				   GFP_ATOMIC);
L
Linus Torvalds 已提交
2965 2966 2967 2968 2969 2970 2971 2972 2973 2974 2975 2976
	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. */
A
Al Viro 已提交
2977
static void sctp_add_asconf_response(struct sctp_chunk *chunk, __be32 crr_id,
2978 2979
				     __be16 err_code,
				     struct sctp_addip_param *asconf_param)
L
Linus Torvalds 已提交
2980
{
2981
	struct sctp_addip_param ack_param;
2982 2983 2984 2985
	struct sctp_errhdr err_param;
	int asconf_param_len = 0;
	int err_param_len = 0;
	__be16 response_type;
L
Linus Torvalds 已提交
2986 2987 2988 2989 2990 2991 2992 2993 2994 2995 2996

	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);
	}

2997
	/* Add Success Indication or Error Cause Indication parameter. */
L
Linus Torvalds 已提交
2998 2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018
	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. */
3019
static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
3020 3021
					struct sctp_chunk *asconf,
					struct sctp_addip_param *asconf_param)
L
Linus Torvalds 已提交
3022
{
3023
	union sctp_addr_param *addr_param;
L
Linus Torvalds 已提交
3024 3025
	struct sctp_transport *peer;
	union sctp_addr	addr;
3026
	struct sctp_af *af;
3027

3028
	addr_param = (void *)asconf_param + sizeof(*asconf_param);
3029

3030 3031 3032 3033 3034
	if (asconf_param->param_hdr.type != SCTP_PARAM_ADD_IP &&
	    asconf_param->param_hdr.type != SCTP_PARAM_DEL_IP &&
	    asconf_param->param_hdr.type != SCTP_PARAM_SET_PRIMARY)
		return SCTP_ERROR_UNKNOWN_PARAM;

3035
	switch (addr_param->p.type) {
3036 3037
	case SCTP_PARAM_IPV6_ADDRESS:
		if (!asoc->peer.ipv6_address)
3038
			return SCTP_ERROR_DNS_FAILED;
3039 3040 3041
		break;
	case SCTP_PARAM_IPV4_ADDRESS:
		if (!asoc->peer.ipv4_address)
3042
			return SCTP_ERROR_DNS_FAILED;
3043 3044
		break;
	default:
3045
		return SCTP_ERROR_DNS_FAILED;
3046 3047
	}

3048
	af = sctp_get_af_specific(param_type2af(addr_param->p.type));
L
Linus Torvalds 已提交
3049
	if (unlikely(!af))
3050
		return SCTP_ERROR_DNS_FAILED;
L
Linus Torvalds 已提交
3051

3052
	af->from_addr_param(&addr, addr_param, htons(asoc->peer.port), 0);
3053 3054 3055 3056 3057 3058 3059

	/* ADDIP 4.2.1  This parameter MUST NOT contain a broadcast
	 * or multicast address.
	 * (note: wildcard is permitted and requires special handling so
	 *  make sure we check for that)
	 */
	if (!af->is_any(&addr) && !af->addr_valid(&addr, NULL, asconf->skb))
3060
		return SCTP_ERROR_DNS_FAILED;
3061

L
Linus Torvalds 已提交
3062 3063
	switch (asconf_param->param_hdr.type) {
	case SCTP_PARAM_ADD_IP:
3064 3065 3066 3067 3068 3069 3070
		/* Section 4.2.1:
		 * If the address 0.0.0.0 or ::0 is provided, the source
		 * address of the packet MUST be added.
		 */
		if (af->is_any(&addr))
			memcpy(&addr, &asconf->source, sizeof(addr));

L
Linus Torvalds 已提交
3071
		/* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
3072 3073 3074 3075 3076
		 * 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'.
		 */
L
Linus Torvalds 已提交
3077

3078
		peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC, SCTP_UNCONFIRMED);
L
Linus Torvalds 已提交
3079 3080 3081 3082
		if (!peer)
			return SCTP_ERROR_RSRC_LOW;

		/* Start the heartbeat timer. */
3083
		sctp_transport_reset_hb_timer(peer);
3084
		asoc->new_transport = peer;
L
Linus Torvalds 已提交
3085 3086 3087
		break;
	case SCTP_PARAM_DEL_IP:
		/* ADDIP 4.3 D7) If a request is received to delete the
3088 3089 3090 3091
		 * 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'.
		 */
3092
		if (asoc->peer.transport_count == 1)
L
Linus Torvalds 已提交
3093 3094 3095 3096 3097 3098 3099 3100 3101
			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'
		 */
3102
		if (sctp_cmp_addr_exact(&asconf->source, &addr))
L
Linus Torvalds 已提交
3103 3104
			return SCTP_ERROR_DEL_SRC_IP;

3105 3106 3107 3108 3109 3110 3111 3112 3113
		/* Section 4.2.2
		 * If the address 0.0.0.0 or ::0 is provided, all
		 * addresses of the peer except	the source address of the
		 * packet MUST be deleted.
		 */
		if (af->is_any(&addr)) {
			sctp_assoc_set_primary(asoc, asconf->transport);
			sctp_assoc_del_nonprimary_peers(asoc,
							asconf->transport);
3114 3115 3116 3117 3118 3119 3120 3121 3122 3123 3124 3125 3126
			return SCTP_ERROR_NO_ERROR;
		}

		/* If the address is not part of the association, the
		 * ASCONF-ACK with Error Cause Indication Parameter
		 * which including cause of Unresolvable Address should
		 * be sent.
		 */
		peer = sctp_assoc_lookup_paddr(asoc, &addr);
		if (!peer)
			return SCTP_ERROR_DNS_FAILED;

		sctp_assoc_rm_peer(asoc, peer);
L
Linus Torvalds 已提交
3127 3128
		break;
	case SCTP_PARAM_SET_PRIMARY:
3129 3130 3131 3132 3133 3134 3135 3136
		/* ADDIP Section 4.2.4
		 * If the address 0.0.0.0 or ::0 is provided, the receiver
		 * MAY mark the source address of the packet as its
		 * primary.
		 */
		if (af->is_any(&addr))
			memcpy(&addr.v4, sctp_source(asconf), sizeof(addr));

3137
		peer = sctp_assoc_lookup_paddr(asoc, &addr);
L
Linus Torvalds 已提交
3138
		if (!peer)
3139
			return SCTP_ERROR_DNS_FAILED;
L
Linus Torvalds 已提交
3140 3141 3142 3143 3144 3145 3146 3147

		sctp_assoc_set_primary(asoc, peer);
		break;
	}

	return SCTP_ERROR_NO_ERROR;
}

3148 3149 3150 3151 3152
/* Verify the ASCONF packet before we process it. */
bool sctp_verify_asconf(const struct sctp_association *asoc,
			struct sctp_chunk *chunk, bool addr_param_needed,
			struct sctp_paramhdr **errp)
{
3153
	struct sctp_addip_chunk *addip;
3154
	bool addr_param_seen = false;
3155
	union sctp_params param;
3156

3157
	addip = (struct sctp_addip_chunk *)chunk->chunk_hdr;
3158 3159
	sctp_walk_params(param, addip, addip_hdr.params) {
		size_t length = ntohs(param.p->length);
3160

3161
		*errp = param.p;
3162
		switch (param.p->type) {
3163 3164 3165
		case SCTP_PARAM_ERR_CAUSE:
			break;
		case SCTP_PARAM_IPV4_ADDRESS:
3166
			if (length != sizeof(struct sctp_ipv4addr_param))
3167
				return false;
3168 3169 3170 3171 3172
			/* ensure there is only one addr param and it's in the
			 * beginning of addip_hdr params, or we reject it.
			 */
			if (param.v != addip->addip_hdr.params)
				return false;
3173 3174 3175
			addr_param_seen = true;
			break;
		case SCTP_PARAM_IPV6_ADDRESS:
3176
			if (length != sizeof(struct sctp_ipv6addr_param))
3177
				return false;
3178 3179
			if (param.v != addip->addip_hdr.params)
				return false;
3180 3181
			addr_param_seen = true;
			break;
3182 3183 3184
		case SCTP_PARAM_ADD_IP:
		case SCTP_PARAM_DEL_IP:
		case SCTP_PARAM_SET_PRIMARY:
3185 3186 3187 3188
			/* In ASCONF chunks, these need to be first. */
			if (addr_param_needed && !addr_param_seen)
				return false;
			length = ntohs(param.addip->param_hdr.length);
3189
			if (length < sizeof(struct sctp_addip_param) +
3190
				     sizeof(**errp))
3191
				return false;
3192 3193 3194
			break;
		case SCTP_PARAM_SUCCESS_REPORT:
		case SCTP_PARAM_ADAPTATION_LAYER_IND:
3195
			if (length != sizeof(struct sctp_addip_param))
3196
				return false;
3197 3198
			break;
		default:
3199 3200
			/* This is unkown to us, reject! */
			return false;
3201 3202 3203
		}
	}

3204 3205 3206 3207 3208 3209 3210
	/* Remaining sanity checks. */
	if (addr_param_needed && !addr_param_seen)
		return false;
	if (!addr_param_needed && addr_param_seen)
		return false;
	if (param.v != chunk->chunk_end)
		return false;
3211

3212
	return true;
3213 3214
}

3215
/* Process an incoming ASCONF chunk with the next expected serial no. and
L
Linus Torvalds 已提交
3216 3217 3218 3219 3220
 * return an ASCONF_ACK chunk to be sent in response.
 */
struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
				       struct sctp_chunk *asconf)
{
3221
	union sctp_addr_param *addr_param;
3222
	struct sctp_addip_chunk *addip;
3223
	struct sctp_chunk *asconf_ack;
3224
	bool all_param_pass = true;
3225 3226
	struct sctp_addiphdr *hdr;
	int length = 0, chunk_len;
3227
	union sctp_params param;
3228 3229
	__be16 err_code;
	__u32 serial;
L
Linus Torvalds 已提交
3230

3231
	addip = (struct sctp_addip_chunk *)asconf->chunk_hdr;
3232 3233
	chunk_len = ntohs(asconf->chunk_hdr->length) -
		    sizeof(struct sctp_chunkhdr);
3234
	hdr = (struct sctp_addiphdr *)asconf->skb->data;
L
Linus Torvalds 已提交
3235 3236
	serial = ntohl(hdr->serial);

3237
	/* Skip the addiphdr and store a pointer to address parameter.  */
3238
	length = sizeof(*hdr);
L
Linus Torvalds 已提交
3239 3240 3241 3242
	addr_param = (union sctp_addr_param *)(asconf->skb->data + length);
	chunk_len -= length;

	/* Skip the address parameter and store a pointer to the first
J
Joe Perches 已提交
3243
	 * asconf parameter.
3244
	 */
3245
	length = ntohs(addr_param->p.length);
L
Linus Torvalds 已提交
3246 3247
	chunk_len -= length;

3248
	/* create an ASCONF_ACK chunk.
L
Linus Torvalds 已提交
3249
	 * Based on the definitions of parameters, we know that the size of
3250
	 * ASCONF_ACK parameters are less than or equal to the fourfold of ASCONF
J
Joe Perches 已提交
3251
	 * parameters.
L
Linus Torvalds 已提交
3252
	 */
3253
	asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 4);
L
Linus Torvalds 已提交
3254 3255 3256 3257
	if (!asconf_ack)
		goto done;

	/* Process the TLVs contained within the ASCONF chunk. */
3258 3259 3260 3261 3262 3263
	sctp_walk_params(param, addip, addip_hdr.params) {
		/* Skip preceeding address parameters. */
		if (param.p->type == SCTP_PARAM_IPV4_ADDRESS ||
		    param.p->type == SCTP_PARAM_IPV6_ADDRESS)
			continue;

L
Linus Torvalds 已提交
3264
		err_code = sctp_process_asconf_param(asoc, asconf,
3265
						     param.addip);
L
Linus Torvalds 已提交
3266 3267 3268 3269 3270 3271 3272
		/* 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.
		 */
3273 3274
		if (err_code != SCTP_ERROR_NO_ERROR)
			all_param_pass = false;
L
Linus Torvalds 已提交
3275
		if (!all_param_pass)
3276 3277
			sctp_add_asconf_response(asconf_ack, param.addip->crr_id,
						 err_code, param.addip);
L
Linus Torvalds 已提交
3278 3279 3280 3281

		/* 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
3282
		 * in the ASCONF.
L
Linus Torvalds 已提交
3283
		 */
3284
		if (err_code == SCTP_ERROR_RSRC_LOW)
L
Linus Torvalds 已提交
3285 3286 3287 3288 3289 3290
			goto done;
	}
done:
	asoc->peer.addip_serial++;

	/* If we are sending a new ASCONF_ACK hold a reference to it in assoc
3291
	 * after freeing the reference to old asconf ack if any.
L
Linus Torvalds 已提交
3292 3293 3294
	 */
	if (asconf_ack) {
		sctp_chunk_hold(asconf_ack);
3295 3296
		list_add_tail(&asconf_ack->transmitted_list,
			      &asoc->asconf_ack_list);
L
Linus Torvalds 已提交
3297 3298 3299 3300 3301 3302
	}

	return asconf_ack;
}

/* Process a asconf parameter that is successfully acked. */
3303
static void sctp_asconf_param_success(struct sctp_association *asoc,
3304
				      struct sctp_addip_param *asconf_param)
L
Linus Torvalds 已提交
3305 3306 3307
{
	struct sctp_bind_addr *bp = &asoc->base.bind_addr;
	union sctp_addr_param *addr_param;
3308
	struct sctp_sockaddr_entry *saddr;
3309 3310 3311
	struct sctp_transport *transport;
	union sctp_addr	addr;
	struct sctp_af *af;
L
Linus Torvalds 已提交
3312

3313
	addr_param = (void *)asconf_param + sizeof(*asconf_param);
L
Linus Torvalds 已提交
3314 3315

	/* We have checked the packet before, so we do not check again.	*/
3316
	af = sctp_get_af_specific(param_type2af(addr_param->p.type));
3317
	af->from_addr_param(&addr, addr_param, htons(bp->port), 0);
L
Linus Torvalds 已提交
3318 3319 3320

	switch (asconf_param->param_hdr.type) {
	case SCTP_PARAM_ADD_IP:
3321 3322 3323
		/* This is always done in BH context with a socket lock
		 * held, so the list can not change.
		 */
3324
		local_bh_disable();
3325
		list_for_each_entry(saddr, &bp->address_list, list) {
3326
			if (sctp_cmp_addr_exact(&saddr->a, &addr))
3327
				saddr->state = SCTP_ADDR_SRC;
3328
		}
3329
		local_bh_enable();
3330 3331
		list_for_each_entry(transport, &asoc->peer.transport_addr_list,
				transports) {
3332
			sctp_transport_dst_release(transport);
3333
		}
L
Linus Torvalds 已提交
3334 3335
		break;
	case SCTP_PARAM_DEL_IP:
3336
		local_bh_disable();
3337
		sctp_del_bind_addr(bp, &addr);
3338 3339 3340 3341 3342
		if (asoc->asconf_addr_del_pending != NULL &&
		    sctp_cmp_addr_exact(asoc->asconf_addr_del_pending, &addr)) {
			kfree(asoc->asconf_addr_del_pending);
			asoc->asconf_addr_del_pending = NULL;
		}
3343
		local_bh_enable();
3344 3345
		list_for_each_entry(transport, &asoc->peer.transport_addr_list,
				transports) {
3346
			sctp_transport_dst_release(transport);
L
Linus Torvalds 已提交
3347 3348 3349 3350 3351 3352 3353 3354 3355
		}
		break;
	default:
		break;
	}
}

/* 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,
3356
 * return the error code based on the third argument 'no_err'.
L
Linus Torvalds 已提交
3357 3358 3359 3360 3361 3362
 * 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.
 */
3363
static __be16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack,
3364 3365
				       struct sctp_addip_param *asconf_param,
				       int no_err)
L
Linus Torvalds 已提交
3366
{
3367
	struct sctp_addip_param	*asconf_ack_param;
3368 3369 3370 3371
	struct sctp_errhdr *err_param;
	int asconf_ack_len;
	__be16 err_code;
	int length;
L
Linus Torvalds 已提交
3372 3373 3374 3375 3376 3377

	if (no_err)
		err_code = SCTP_ERROR_NO_ERROR;
	else
		err_code = SCTP_ERROR_REQ_REFUSED;

3378
	asconf_ack_len = ntohs(asconf_ack->chunk_hdr->length) -
3379
			 sizeof(struct sctp_chunkhdr);
3380

L
Linus Torvalds 已提交
3381 3382
	/* Skip the addiphdr from the asconf_ack chunk and store a pointer to
	 * the first asconf_ack parameter.
3383
	 */
3384
	length = sizeof(struct sctp_addiphdr);
3385 3386
	asconf_ack_param = (struct sctp_addip_param *)(asconf_ack->skb->data +
						       length);
L
Linus Torvalds 已提交
3387 3388 3389 3390
	asconf_ack_len -= length;

	while (asconf_ack_len > 0) {
		if (asconf_ack_param->crr_id == asconf_param->crr_id) {
3391
			switch (asconf_ack_param->param_hdr.type) {
L
Linus Torvalds 已提交
3392 3393 3394
			case SCTP_PARAM_SUCCESS_REPORT:
				return SCTP_ERROR_NO_ERROR;
			case SCTP_PARAM_ERR_CAUSE:
3395
				length = sizeof(*asconf_ack_param);
J
Joe Perches 已提交
3396
				err_param = (void *)asconf_ack_param + length;
L
Linus Torvalds 已提交
3397 3398 3399 3400 3401 3402 3403 3404 3405 3406 3407 3408
				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);
J
Joe Perches 已提交
3409
		asconf_ack_param = (void *)asconf_ack_param + length;
L
Linus Torvalds 已提交
3410 3411 3412 3413 3414 3415 3416 3417 3418 3419
		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)
{
3420 3421 3422 3423 3424 3425 3426 3427 3428
	struct sctp_chunk *asconf = asoc->addip_last_asconf;
	struct sctp_addip_param *asconf_param;
	__be16 err_code = SCTP_ERROR_NO_ERROR;
	union sctp_addr_param *addr_param;
	int asconf_len = asconf->skb->len;
	int all_param_pass = 0;
	int length = 0;
	int no_err = 1;
	int retval = 0;
L
Linus Torvalds 已提交
3429 3430 3431

	/* Skip the chunkhdr and addiphdr from the last asconf sent and store
	 * a pointer to address parameter.
3432
	 */
3433
	length = sizeof(struct sctp_addip_chunk);
L
Linus Torvalds 已提交
3434 3435 3436 3437
	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
J
Joe Perches 已提交
3438
	 * pointer to the first asconf parameter.
3439
	 */
3440
	length = ntohs(addr_param->p.length);
J
Joe Perches 已提交
3441
	asconf_param = (void *)addr_param + length;
L
Linus Torvalds 已提交
3442 3443 3444 3445 3446 3447 3448
	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.
	 */
3449
	if (asconf_ack->skb->len == sizeof(struct sctp_addiphdr))
L
Linus Torvalds 已提交
3450 3451 3452 3453 3454 3455 3456 3457 3458 3459 3460 3461 3462 3463 3464 3465
		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:
3466
			sctp_asconf_param_success(asoc, asconf_param);
L
Linus Torvalds 已提交
3467 3468 3469 3470 3471 3472
			break;

		case SCTP_ERROR_RSRC_LOW:
			retval = 1;
			break;

3473
		case SCTP_ERROR_UNKNOWN_PARAM:
L
Linus Torvalds 已提交
3474 3475
			/* Disable sending this type of asconf parameter in
			 * future.
3476
			 */
L
Linus Torvalds 已提交
3477 3478 3479 3480 3481 3482 3483 3484 3485 3486 3487 3488 3489
			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.
3490
		 */
L
Linus Torvalds 已提交
3491
		length = ntohs(asconf_param->param_hdr.length);
J
Joe Perches 已提交
3492
		asconf_param = (void *)asconf_param + length;
L
Linus Torvalds 已提交
3493 3494 3495
		asconf_len -= length;
	}

3496
	if (no_err && asoc->src_out_of_asoc_ok) {
3497
		asoc->src_out_of_asoc_ok = 0;
3498 3499
		sctp_transport_immediate_rtx(asoc->peer.primary_path);
	}
3500

L
Linus Torvalds 已提交
3501
	/* Free the cached last sent asconf chunk. */
3502
	list_del_init(&asconf->transmitted_list);
L
Linus Torvalds 已提交
3503 3504 3505 3506 3507 3508
	sctp_chunk_free(asconf);
	asoc->addip_last_asconf = NULL;

	return retval;
}

3509
/* Make a FWD TSN chunk. */
L
Linus Torvalds 已提交
3510 3511 3512 3513 3514
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;
3515
	struct sctp_fwdtsn_hdr ftsn_hdr;
L
Linus Torvalds 已提交
3516 3517 3518 3519 3520 3521
	struct sctp_fwdtsn_skip skip;
	size_t hint;
	int i;

	hint = (nstreams + 1) * sizeof(__u32);

3522
	retval = sctp_make_control(asoc, SCTP_CID_FWD_TSN, 0, hint, GFP_ATOMIC);
L
Linus Torvalds 已提交
3523 3524 3525 3526 3527 3528 3529 3530 3531 3532 3533 3534 3535 3536 3537 3538

	if (!retval)
		return NULL;

	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;
}
3539 3540 3541 3542 3543 3544 3545 3546 3547 3548 3549 3550 3551 3552 3553 3554

/* RE-CONFIG 3.1 (RE-CONFIG chunk)
 *   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 = 130    |  Chunk Flags  |      Chunk Length             |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  \                                                               \
 *  /                  Re-configuration Parameter                   /
 *  \                                                               \
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  \                                                               \
 *  /             Re-configuration Parameter (optional)             /
 *  \                                                               \
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 */
3555 3556
static struct sctp_chunk *sctp_make_reconf(const struct sctp_association *asoc,
					   int length)
3557 3558 3559 3560 3561 3562 3563 3564 3565 3566 3567 3568 3569 3570 3571 3572 3573 3574 3575 3576 3577 3578 3579 3580 3581 3582 3583 3584 3585 3586 3587 3588 3589 3590 3591 3592 3593 3594 3595 3596 3597 3598 3599 3600 3601 3602 3603 3604 3605 3606
{
	struct sctp_reconf_chunk *reconf;
	struct sctp_chunk *retval;

	retval = sctp_make_control(asoc, SCTP_CID_RECONF, 0, length,
				   GFP_ATOMIC);
	if (!retval)
		return NULL;

	reconf = (struct sctp_reconf_chunk *)retval->chunk_hdr;
	retval->param_hdr.v = reconf->params;

	return retval;
}

/* RE-CONFIG 4.1 (STREAM OUT RESET)
 *   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
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |     Parameter Type = 13       | Parameter Length = 16 + 2 * N |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |           Re-configuration Request Sequence Number            |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |           Re-configuration Response Sequence Number           |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |                Sender's Last Assigned TSN                     |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |  Stream Number 1 (optional)   |    Stream Number 2 (optional) |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  /                            ......                             /
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |  Stream Number N-1 (optional) |    Stream Number N (optional) |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 * RE-CONFIG 4.2 (STREAM IN RESET)
 *   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
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |     Parameter Type = 14       |  Parameter Length = 8 + 2 * N |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |          Re-configuration Request Sequence Number             |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |  Stream Number 1 (optional)   |    Stream Number 2 (optional) |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  /                            ......                             /
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |  Stream Number N-1 (optional) |    Stream Number N (optional) |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 */
struct sctp_chunk *sctp_make_strreset_req(
3607
					const struct sctp_association *asoc,
3608
					__u16 stream_num, __be16 *stream_list,
3609
					bool out, bool in)
3610
{
3611
	__u16 stream_len = stream_num * sizeof(__u16);
3612 3613 3614
	struct sctp_strreset_outreq outreq;
	struct sctp_strreset_inreq inreq;
	struct sctp_chunk *retval;
3615
	__u16 outlen, inlen;
3616 3617 3618 3619 3620 3621 3622 3623 3624 3625 3626 3627 3628 3629 3630 3631 3632 3633 3634 3635 3636 3637 3638 3639 3640 3641 3642 3643 3644 3645 3646 3647 3648 3649

	outlen = (sizeof(outreq) + stream_len) * out;
	inlen = (sizeof(inreq) + stream_len) * in;

	retval = sctp_make_reconf(asoc, outlen + inlen);
	if (!retval)
		return NULL;

	if (outlen) {
		outreq.param_hdr.type = SCTP_PARAM_RESET_OUT_REQUEST;
		outreq.param_hdr.length = htons(outlen);
		outreq.request_seq = htonl(asoc->strreset_outseq);
		outreq.response_seq = htonl(asoc->strreset_inseq - 1);
		outreq.send_reset_at_tsn = htonl(asoc->next_tsn - 1);

		sctp_addto_chunk(retval, sizeof(outreq), &outreq);

		if (stream_len)
			sctp_addto_chunk(retval, stream_len, stream_list);
	}

	if (inlen) {
		inreq.param_hdr.type = SCTP_PARAM_RESET_IN_REQUEST;
		inreq.param_hdr.length = htons(inlen);
		inreq.request_seq = htonl(asoc->strreset_outseq + out);

		sctp_addto_chunk(retval, sizeof(inreq), &inreq);

		if (stream_len)
			sctp_addto_chunk(retval, stream_len, stream_list);
	}

	return retval;
}
3650 3651 3652 3653 3654 3655 3656 3657 3658 3659 3660

/* RE-CONFIG 4.3 (SSN/TSN RESET ALL)
 *   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
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |     Parameter Type = 15       |      Parameter Length = 8     |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |         Re-configuration Request Sequence Number              |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 */
struct sctp_chunk *sctp_make_strreset_tsnreq(
3661
					const struct sctp_association *asoc)
3662 3663 3664 3665 3666 3667 3668 3669 3670 3671 3672 3673 3674 3675 3676 3677 3678
{
	struct sctp_strreset_tsnreq tsnreq;
	__u16 length = sizeof(tsnreq);
	struct sctp_chunk *retval;

	retval = sctp_make_reconf(asoc, length);
	if (!retval)
		return NULL;

	tsnreq.param_hdr.type = SCTP_PARAM_RESET_TSN_REQUEST;
	tsnreq.param_hdr.length = htons(length);
	tsnreq.request_seq = htonl(asoc->strreset_outseq);

	sctp_addto_chunk(retval, sizeof(tsnreq), &tsnreq);

	return retval;
}
3679 3680 3681 3682 3683 3684 3685 3686 3687 3688 3689 3690 3691

/* RE-CONFIG 4.5/4.6 (ADD STREAM)
 *   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
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |     Parameter Type = 17       |      Parameter Length = 12    |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |          Re-configuration Request Sequence Number             |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |      Number of new streams    |         Reserved              |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 */
struct sctp_chunk *sctp_make_strreset_addstrm(
3692 3693
					const struct sctp_association *asoc,
					__u16 out, __u16 in)
3694 3695 3696 3697 3698 3699 3700 3701 3702 3703 3704 3705 3706 3707 3708 3709 3710 3711 3712 3713 3714 3715 3716 3717 3718 3719 3720 3721 3722 3723 3724
{
	struct sctp_strreset_addstrm addstrm;
	__u16 size = sizeof(addstrm);
	struct sctp_chunk *retval;

	retval = sctp_make_reconf(asoc, (!!out + !!in) * size);
	if (!retval)
		return NULL;

	if (out) {
		addstrm.param_hdr.type = SCTP_PARAM_RESET_ADD_OUT_STREAMS;
		addstrm.param_hdr.length = htons(size);
		addstrm.number_of_streams = htons(out);
		addstrm.request_seq = htonl(asoc->strreset_outseq);
		addstrm.reserved = 0;

		sctp_addto_chunk(retval, size, &addstrm);
	}

	if (in) {
		addstrm.param_hdr.type = SCTP_PARAM_RESET_ADD_IN_STREAMS;
		addstrm.param_hdr.length = htons(size);
		addstrm.number_of_streams = htons(in);
		addstrm.request_seq = htonl(asoc->strreset_outseq + !!out);
		addstrm.reserved = 0;

		sctp_addto_chunk(retval, size, &addstrm);
	}

	return retval;
}
3725 3726 3727 3728 3729 3730 3731 3732 3733 3734 3735 3736

/* RE-CONFIG 4.4 (RESP)
 *   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
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |     Parameter Type = 16       |      Parameter Length         |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |         Re-configuration Response Sequence Number             |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |                            Result                             |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 */
3737 3738
struct sctp_chunk *sctp_make_strreset_resp(const struct sctp_association *asoc,
					   __u32 result, __u32 sn)
3739 3740 3741 3742 3743 3744 3745 3746 3747 3748 3749 3750 3751 3752 3753 3754 3755 3756 3757 3758 3759 3760 3761 3762 3763 3764 3765 3766 3767 3768 3769 3770 3771 3772
{
	struct sctp_strreset_resp resp;
	__u16 length = sizeof(resp);
	struct sctp_chunk *retval;

	retval = sctp_make_reconf(asoc, length);
	if (!retval)
		return NULL;

	resp.param_hdr.type = SCTP_PARAM_RESET_RESPONSE;
	resp.param_hdr.length = htons(length);
	resp.response_seq = htonl(sn);
	resp.result = htonl(result);

	sctp_addto_chunk(retval, sizeof(resp), &resp);

	return retval;
}

/* RE-CONFIG 4.4 OPTIONAL (TSNRESP)
 *   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
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |     Parameter Type = 16       |      Parameter Length         |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |         Re-configuration Response Sequence Number             |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |                            Result                             |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |                   Sender's Next TSN (optional)                |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |                  Receiver's Next TSN (optional)               |
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 */
3773 3774 3775 3776
struct sctp_chunk *sctp_make_strreset_tsnresp(struct sctp_association *asoc,
					      __u32 result, __u32 sn,
					      __u32 sender_tsn,
					      __u32 receiver_tsn)
3777 3778 3779 3780 3781 3782 3783 3784 3785 3786 3787 3788 3789 3790 3791 3792 3793 3794 3795 3796 3797
{
	struct sctp_strreset_resptsn tsnresp;
	__u16 length = sizeof(tsnresp);
	struct sctp_chunk *retval;

	retval = sctp_make_reconf(asoc, length);
	if (!retval)
		return NULL;

	tsnresp.param_hdr.type = SCTP_PARAM_RESET_RESPONSE;
	tsnresp.param_hdr.length = htons(length);

	tsnresp.response_seq = htonl(sn);
	tsnresp.result = htonl(result);
	tsnresp.senders_next_tsn = htonl(sender_tsn);
	tsnresp.receivers_next_tsn = htonl(receiver_tsn);

	sctp_addto_chunk(retval, sizeof(tsnresp), &tsnresp);

	return retval;
}
3798 3799 3800 3801 3802 3803 3804

bool sctp_verify_reconf(const struct sctp_association *asoc,
			struct sctp_chunk *chunk,
			struct sctp_paramhdr **errp)
{
	struct sctp_reconf_chunk *hdr;
	union sctp_params param;
3805 3806
	__be16 last = 0;
	__u16 cnt = 0;
3807 3808 3809 3810 3811 3812 3813 3814 3815 3816 3817 3818 3819 3820 3821 3822 3823 3824 3825 3826 3827 3828 3829 3830 3831 3832 3833 3834 3835 3836 3837 3838 3839 3840 3841 3842 3843 3844 3845 3846 3847 3848 3849 3850 3851 3852 3853 3854 3855 3856 3857

	hdr = (struct sctp_reconf_chunk *)chunk->chunk_hdr;
	sctp_walk_params(param, hdr, params) {
		__u16 length = ntohs(param.p->length);

		*errp = param.p;
		if (cnt++ > 2)
			return false;
		switch (param.p->type) {
		case SCTP_PARAM_RESET_OUT_REQUEST:
			if (length < sizeof(struct sctp_strreset_outreq) ||
			    (last && last != SCTP_PARAM_RESET_RESPONSE &&
			     last != SCTP_PARAM_RESET_IN_REQUEST))
				return false;
			break;
		case SCTP_PARAM_RESET_IN_REQUEST:
			if (length < sizeof(struct sctp_strreset_inreq) ||
			    (last && last != SCTP_PARAM_RESET_OUT_REQUEST))
				return false;
			break;
		case SCTP_PARAM_RESET_RESPONSE:
			if ((length != sizeof(struct sctp_strreset_resp) &&
			     length != sizeof(struct sctp_strreset_resptsn)) ||
			    (last && last != SCTP_PARAM_RESET_RESPONSE &&
			     last != SCTP_PARAM_RESET_OUT_REQUEST))
				return false;
			break;
		case SCTP_PARAM_RESET_TSN_REQUEST:
			if (length !=
			    sizeof(struct sctp_strreset_tsnreq) || last)
				return false;
			break;
		case SCTP_PARAM_RESET_ADD_IN_STREAMS:
			if (length != sizeof(struct sctp_strreset_addstrm) ||
			    (last && last != SCTP_PARAM_RESET_ADD_OUT_STREAMS))
				return false;
			break;
		case SCTP_PARAM_RESET_ADD_OUT_STREAMS:
			if (length != sizeof(struct sctp_strreset_addstrm) ||
			    (last && last != SCTP_PARAM_RESET_ADD_IN_STREAMS))
				return false;
			break;
		default:
			return false;
		}

		last = param.p->type;
	}

	return true;
}