cregit-Linux how code gets into the kernel

Release 4.8 net/sctp/sm_make_chunk.c

Directory: net/sctp
/* SCTP kernel implementation
 * (C) Copyright IBM Corp. 2001, 2004
 * Copyright (c) 1999-2000 Cisco, Inc.
 * Copyright (c) 1999-2001 Motorola, Inc.
 * Copyright (c) 2001-2002 Intel Corp.
 *
 * This file is part of the SCTP kernel implementation
 *
 * These functions work with the state functions in sctp_sm_statefuns.c
 * to implement the state operations.  These functions implement the
 * steps which require modifying existing data structures.
 *
 * This SCTP implementation is free software;
 * you can redistribute it and/or modify it under the terms of
 * the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This SCTP implementation is distributed in the hope that it
 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
 *                 ************************
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with GNU CC; see the file COPYING.  If not, see
 * <http://www.gnu.org/licenses/>.
 *
 * Please send any bug reports or fixes you make to the
 * email address(es):
 *    lksctp developers <linux-sctp@vger.kernel.org>
 *
 * 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>
 */


#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

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

#include <linux/skbuff.h>
#include <linux/random.h>	/* for get_random_bytes */
#include <net/sctp/sctp.h>
#include <net/sctp/sm.h>

static struct sctp_chunk *sctp_make_control(const struct sctp_association *asoc,
					    __u8 type, __u8 flags, int paylen,
					    gfp_t gfp);
static struct sctp_chunk *sctp_make_data(const struct sctp_association *asoc,
					 __u8 flags, int paylen, gfp_t gfp);
static struct sctp_chunk *_sctp_make_chunk(const struct sctp_association *asoc,
					   __u8 type, __u8 flags, int paylen,
					   gfp_t gfp);
static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
					const struct sctp_association *asoc,
					const struct sctp_chunk *init_chunk,
					int *cookie_len,
					const __u8 *raw_addrs, int addrs_len);
static int sctp_process_param(struct sctp_association *asoc,
			      union sctp_params param,
			      const union sctp_addr *peer_addr,
			      gfp_t gfp);
static void *sctp_addto_param(struct sctp_chunk *chunk, int len,
			      const void *data);
static void  *sctp_addto_chunk_fixed(struct sctp_chunk *, int len,
				     const void *data);

/* Control chunk destructor */

static void sctp_control_release_owner(struct sk_buff *skb) { /*TODO: do memory release */ }

Contributors

PersonTokensPropCommitsCommitProp
vlad yasevichvlad yasevich12100.00%1100.00%
Total12100.00%1100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
vlad yasevichvlad yasevich50100.00%1100.00%
Total50100.00%1100.00%

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

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm2575.76%133.33%
marcelo ricardo leitnermarcelo ricardo leitner721.21%133.33%
arnaldo carvalho de meloarnaldo carvalho de melo13.03%133.33%
Total33100.00%3100.00%

/* 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, cpu_to_be16(sizeof(struct sctp_paramhdr)), }; static const struct sctp_paramhdr prsctp_param = { SCTP_PARAM_FWD_TSN_SUPPORT, cpu_to_be16(sizeof(struct sctp_paramhdr)), }; /* A helper to initialize an op error inside a * provided chunk, as most cause codes will be embedded inside an * abort chunk. */
void sctp_init_cause(struct sctp_chunk *chunk, __be16 cause_code, size_t paylen) { sctp_errhdr_t err; __u16 len; /* Cause code constants are now defined in network order. */ err.cause = cause_code; len = sizeof(sctp_errhdr_t) + paylen; err.length = htons(len); chunk->subh.err_hdr = sctp_addto_chunk(chunk, sizeof(sctp_errhdr_t), &err); }

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm5684.85%240.00%
vladislav yasevichvladislav yasevich69.09%120.00%
david s. millerdavid s. miller34.55%120.00%
al viroal viro11.52%120.00%
Total66100.00%5100.00%

/* 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 */
static int sctp_init_cause_fixed(struct sctp_chunk *chunk, __be16 cause_code, size_t paylen) { sctp_errhdr_t err; __u16 len; /* Cause code constants are now defined in network order. */ err.cause = cause_code; len = sizeof(sctp_errhdr_t) + paylen; err.length = htons(len); if (skb_tailroom(chunk->skb) < len) return -ENOSPC; chunk->subh.err_hdr = sctp_addto_chunk_fixed(chunk, sizeof(sctp_errhdr_t), &err); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
neil hormanneil horman8397.65%133.33%
wei yongjunwei yongjun11.18%133.33%
ioan orghiciioan orghici11.18%133.33%
Total85100.00%3100.00%

/* 3.3.2 Initiation (INIT) (1) * * This chunk is used to initiate a SCTP association between two * endpoints. The format of the INIT chunk is shown below: * * 0 1 2 3 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | Type = 1 | Chunk Flags | Chunk Length | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | Initiate Tag | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | Advertised Receiver Window Credit (a_rwnd) | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | Number of Outbound Streams | Number of Inbound Streams | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | Initial TSN | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * \ \ * / Optional/Variable-Length Parameters / * \ \ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * * * The INIT chunk contains the following parameters. Unless otherwise * noted, each parameter MUST only be included once in the INIT chunk. * * Fixed Parameters Status * ---------------------------------------------- * Initiate Tag Mandatory * Advertised Receiver Window Credit Mandatory * Number of Outbound Streams Mandatory * Number of Inbound Streams Mandatory * Initial TSN Mandatory * * Variable Parameters Status Type Value * ------------------------------------------------------------- * IPv4 Address (Note 1) Optional 5 * IPv6 Address (Note 1) Optional 6 * Cookie Preservative Optional 9 * Reserved for ECN Capable (Note 2) Optional 32768 (0x8000) * Host Name Address (Note 3) Optional 11 * Supported Address Types (Note 4) Optional 12 */
struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc, const struct sctp_bind_addr *bp, gfp_t gfp, int vparam_len) { struct net *net = sock_net(asoc->base.sk); struct sctp_endpoint *ep = asoc->ep; sctp_inithdr_t init; union sctp_params addrs; size_t chunksize; struct sctp_chunk *retval = NULL; int num_types, addrs_len = 0; struct sctp_sock *sp; sctp_supported_addrs_param_t sat; __be16 types[2]; sctp_adaptation_ind_param_t aiparam; sctp_supported_ext_param_t ext_param; int num_ext = 0; __u8 extensions[3]; sctp_paramhdr_t *auth_chunks = NULL, *auth_hmacs = NULL; /* RFC 2960 3.3.2 Initiation (INIT) (1) * * Note 1: The INIT chunks can contain multiple addresses that * can be IPv4 and/or IPv6 in any combination. */ retval = NULL; /* Convert the provided bind address list to raw format. */ addrs = sctp_bind_addrs_to_raw(bp, &addrs_len, gfp); init.init_tag = htonl(asoc->c.my_vtag); init.a_rwnd = htonl(asoc->rwnd); init.num_outbound_streams = htons(asoc->c.sinit_num_ostreams); init.num_inbound_streams = htons(asoc->c.sinit_max_instreams); init.initial_tsn = htonl(asoc->c.initial_tsn); /* How many address types are needed? */ sp = sctp_sk(asoc->base.sk); num_types = sp->pf->supported_addrs(sp, types); chunksize = sizeof(init) + addrs_len; chunksize += WORD_ROUND(SCTP_SAT_LEN(num_types)); chunksize += sizeof(ecap_param); if (asoc->prsctp_enable) chunksize += sizeof(prsctp_param); /* 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. */ if (net->sctp.addip_enable) { extensions[num_ext] = SCTP_CID_ASCONF; extensions[num_ext+1] = SCTP_CID_ASCONF_ACK; num_ext += 2; } if (sp->adaptation_ind) chunksize += sizeof(aiparam); chunksize += vparam_len; /* Account for AUTH related parameters */ if (ep->auth_enable) { /* Add random parameter length*/ chunksize += sizeof(asoc->c.auth_random); /* Add HMACS parameter length if any were defined */ auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs; if (auth_hmacs->length) chunksize += WORD_ROUND(ntohs(auth_hmacs->length)); else auth_hmacs = NULL; /* Add CHUNKS parameter length */ auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks; if (auth_chunks->length) chunksize += WORD_ROUND(ntohs(auth_chunks->length)); else auth_chunks = NULL; extensions[num_ext] = SCTP_CID_AUTH; num_ext += 1; } /* If we have any extensions to report, account for that */ if (num_ext) chunksize += WORD_ROUND(sizeof(sctp_supported_ext_param_t) + num_ext); /* RFC 2960 3.3.2 Initiation (INIT) (1) * * Note 3: An INIT chunk MUST NOT contain more than one Host * Name address parameter. Moreover, the sender of the INIT * MUST NOT combine any other address types with the Host Name * address in the INIT. The receiver of INIT MUST ignore any * other address types if the Host Name address parameter is * present in the received INIT chunk. * * PLEASE DO NOT FIXME [This version does not support Host Name.] */ retval = sctp_make_control(asoc, SCTP_CID_INIT, 0, chunksize, gfp); 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); /* Add the supported extensions parameter. Be nice and add this * fist before addiding the parameters for the extensions themselves */ if (num_ext) { ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT; ext_param.param_hdr.length = htons(sizeof(sctp_supported_ext_param_t) + num_ext); sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t), &ext_param); sctp_addto_param(retval, num_ext, extensions); } if (asoc->prsctp_enable) sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param); 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); } /* Add SCTP-AUTH chunks to the parameter list */ if (ep->auth_enable) { 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); } nodata: kfree(addrs.v); return retval; }

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm30039.74%724.14%
vladislav yasevichvladislav yasevich28437.62%517.24%
sridhar samudralasridhar samudrala8811.66%413.79%
eric w. biedermaneric w. biederman273.58%13.45%
wei yongjunwei yongjun151.99%13.45%
malc at gmail.commalc at gmail.com141.85%13.45%
vlad yasevichvlad yasevich121.59%26.90%
ivan skytte jorgensenivan skytte jorgensen40.53%13.45%
david s. millerdavid s. miller30.40%13.45%
lucien xinlucien xin20.26%13.45%
al viroal viro20.26%26.90%
marcelo ricardo leitnermarcelo ricardo leitner20.26%13.45%
arnaldo carvalho de meloarnaldo carvalho de melo10.13%13.45%
joe perchesjoe perches10.13%13.45%
Total755100.00%29100.00%


struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc, const struct sctp_chunk *chunk, gfp_t gfp, int unkparam_len) { sctp_inithdr_t initack; struct sctp_chunk *retval; union sctp_params addrs; struct sctp_sock *sp; int addrs_len; sctp_cookie_param_t *cookie; int cookie_len; size_t chunksize; sctp_adaptation_ind_param_t aiparam; sctp_supported_ext_param_t ext_param; int num_ext = 0; __u8 extensions[3]; sctp_paramhdr_t *auth_chunks = NULL, *auth_hmacs = NULL, *auth_random = NULL; retval = NULL; /* Note: there may be no addresses to embed. */ addrs = sctp_bind_addrs_to_raw(&asoc->base.bind_addr, &addrs_len, gfp); initack.init_tag = htonl(asoc->c.my_vtag); initack.a_rwnd = htonl(asoc->rwnd); initack.num_outbound_streams = htons(asoc->c.sinit_num_ostreams); initack.num_inbound_streams = htons(asoc->c.sinit_max_instreams); initack.initial_tsn = htonl(asoc->c.initial_tsn); /* FIXME: We really ought to build the cookie right * into the packet instead of allocating more fresh memory. */ cookie = sctp_pack_cookie(asoc->ep, asoc, chunk, &cookie_len, addrs.v, addrs_len); if (!cookie) goto nomem_cookie; /* Calculate the total size of allocation, include the reserved * space for reporting unknown parameters if it is specified. */ sp = sctp_sk(asoc->base.sk); chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len; /* Tell peer that we'll do ECN only if peer advertised such cap. */ if (asoc->peer.ecn_capable) chunksize += sizeof(ecap_param); if (asoc->peer.prsctp_capable) chunksize += sizeof(prsctp_param); if (asoc->peer.asconf_capable) { extensions[num_ext] = SCTP_CID_ASCONF; extensions[num_ext+1] = SCTP_CID_ASCONF_ACK; num_ext += 2; } if (sp->adaptation_ind) chunksize += sizeof(aiparam); if (asoc->peer.auth_capable) { auth_random = (sctp_paramhdr_t *)asoc->c.auth_random; chunksize += ntohs(auth_random->length); auth_hmacs = (sctp_paramhdr_t *)asoc->c.auth_hmacs; if (auth_hmacs->length) chunksize += WORD_ROUND(ntohs(auth_hmacs->length)); else auth_hmacs = NULL; auth_chunks = (sctp_paramhdr_t *)asoc->c.auth_chunks; if (auth_chunks->length) chunksize += WORD_ROUND(ntohs(auth_chunks->length)); else auth_chunks = NULL; extensions[num_ext] = SCTP_CID_AUTH; num_ext += 1; } if (num_ext) chunksize += WORD_ROUND(sizeof(sctp_supported_ext_param_t) + num_ext); /* Now allocate and fill out the chunk. */ retval = sctp_make_control(asoc, SCTP_CID_INIT_ACK, 0, chunksize, gfp); if (!retval) goto nomem_chunk; /* 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.] */ retval->transport = chunk->transport; retval->subh.init_hdr = sctp_addto_chunk(retval, sizeof(initack), &initack); retval->param_hdr.v = sctp_addto_chunk(retval, addrs_len, addrs.v); sctp_addto_chunk(retval, cookie_len, cookie); if (asoc->peer.ecn_capable) sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param); if (num_ext) { ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT; ext_param.param_hdr.length = htons(sizeof(sctp_supported_ext_param_t) + num_ext); sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t), &ext_param); sctp_addto_param(retval, num_ext, extensions); } if (asoc->peer.prsctp_capable) sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param); 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); } 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); } /* We need to remove the const qualifier at this point. */ retval->asoc = (struct sctp_association *) asoc; nomem_chunk: kfree(cookie); nomem_cookie: kfree(addrs.v); return retval; }

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm30841.18%626.09%
vladislav yasevichvladislav yasevich30040.11%417.39%
sridhar samudralasridhar samudrala709.36%313.04%
malc at gmail.commalc at gmail.com314.14%14.35%
wei yongjunwei yongjun192.54%28.70%
daisy changdaisy chang60.80%14.35%
david s. millerdavid s. miller50.67%14.35%
ivan skytte jorgensenivan skytte jorgensen40.53%14.35%
marcelo ricardo leitnermarcelo ricardo leitner20.27%14.35%
dan carpenterdan carpenter10.13%14.35%
al viroal viro10.13%14.35%
vlad yasevichvlad yasevich10.13%14.35%
Total748100.00%23100.00%

/* 3.3.11 Cookie Echo (COOKIE ECHO) (10): * * This chunk is used only during the initialization of an association. * It is sent by the initiator of an association to its peer to complete * the initialization process. This chunk MUST precede any DATA chunk * sent within the association, but MAY be bundled with one or more DATA * chunks in the same packet. * * 0 1 2 3 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | Type = 10 |Chunk Flags | Length | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * / Cookie / * \ \ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * * Chunk Flags: 8 bit * * Set to zero on transmit and ignored on receipt. * * Length: 16 bits (unsigned integer) * * Set to the size of the chunk in bytes, including the 4 bytes of * the chunk header and the size of the Cookie. * * Cookie: variable size * * This field must contain the exact cookie received in the * State Cookie parameter from the previous INIT ACK. * * An implementation SHOULD make the cookie as small as possible * to insure interoperability. */
struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc, const struct sctp_chunk *chunk) { struct sctp_chunk *retval; void *cookie; int cookie_len; cookie = asoc->peer.cookie; cookie_len = asoc->peer.cookie_len; /* Build a cookie echo chunk. */ retval = sctp_make_control(asoc, SCTP_CID_COOKIE_ECHO, 0, cookie_len, GFP_ATOMIC); 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; }

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm9995.19%350.00%
marcelo ricardo leitnermarcelo ricardo leitner21.92%116.67%
david s. millerdavid s. miller21.92%116.67%
vlad yasevichvlad yasevich10.96%116.67%
Total104100.00%6100.00%

/* 3.3.12 Cookie Acknowledgement (COOKIE ACK) (11): * * This chunk is used only during the initialization of an * association. It is used to acknowledge the receipt of a COOKIE * ECHO chunk. This chunk MUST precede any DATA or SACK chunk sent * within the association, but MAY be bundled with one or more DATA * chunks or SACK chunk in the same SCTP packet. * * 0 1 2 3 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | Type = 11 |Chunk Flags | Length = 4 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * * Chunk Flags: 8 bits * * Set to zero on transmit and ignored on receipt. */
struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc, const struct sctp_chunk *chunk) { struct sctp_chunk *retval; retval = sctp_make_control(asoc, SCTP_CID_COOKIE_ACK, 0, 0, GFP_ATOMIC); /* 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; }

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm5392.98%350.00%
marcelo ricardo leitnermarcelo ricardo leitner23.51%116.67%
vlad yasevichvlad yasevich11.75%116.67%
david s. millerdavid s. miller11.75%116.67%
Total57100.00%6100.00%

/* * Appendix A: Explicit Congestion Notification: * CWR: * * RFC 2481 details a specific bit for a sender to send in the header of * its next outbound TCP segment to indicate to its peer that it has * reduced its congestion window. This is termed the CWR bit. For * SCTP the same indication is made by including the CWR chunk. * This chunk contains one data element, i.e. the TSN number that * was sent in the ECNE chunk. This element represents the lowest * TSN number in the datagram that was originally marked with the * CE bit. * * 0 1 2 3 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | Chunk Type=13 | Flags=00000000| Chunk Length = 8 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | Lowest TSN Number | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * * Note: The CWR is considered a Control chunk. */
struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc, const __u32 lowest_tsn, const struct sctp_chunk *chunk) { struct sctp_chunk *retval; sctp_cwrhdr_t cwr; cwr.lowest_tsn = htonl(lowest_tsn); retval = sctp_make_control(asoc, SCTP_CID_ECN_CWR, 0, sizeof(sctp_cwrhdr_t), GFP_ATOMIC); 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; }

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm9794.17%350.00%
david s. millerdavid s. miller32.91%116.67%
marcelo ricardo leitnermarcelo ricardo leitner21.94%116.67%
vlad yasevichvlad yasevich10.97%116.67%
Total103100.00%6100.00%

/* Make an ECNE chunk. This is a congestion experienced report. */
struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc, const __u32 lowest_tsn) { struct sctp_chunk *retval; sctp_ecnehdr_t ecne; ecne.lowest_tsn = htonl(lowest_tsn); retval = sctp_make_control(asoc, SCTP_CID_ECN_ECNE, 0, sizeof(sctp_ecnehdr_t), GFP_ATOMIC); if (!retval) goto nodata; retval->subh.ecne_hdr = sctp_addto_chunk(retval, sizeof(ecne), &ecne); nodata: return retval; }

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm7994.05%350.00%
marcelo ricardo leitnermarcelo ricardo leitner22.38%116.67%
david s. millerdavid s. miller22.38%116.67%
vlad yasevichvlad yasevich11.19%116.67%
Total84100.00%6100.00%

/* Make a DATA chunk for the given association from the provided * parameters. However, do not populate the data payload. */
struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc, const struct sctp_sndrcvinfo *sinfo, int data_len, __u8 flags, __u16 ssn, gfp_t gfp) { struct sctp_chunk *retval; struct sctp_datahdr dp; int chunk_len; /* We assign the TSN as LATE as possible, not here when * creating the chunk. */ dp.tsn = 0; dp.stream = htons(sinfo->sinfo_stream); dp.ppid = sinfo->sinfo_ppid; /* Set the flags for an unordered send. */ if (sinfo->sinfo_flags & SCTP_UNORDERED) { flags |= SCTP_DATA_UNORDERED; dp.ssn = 0; } else dp.ssn = htons(ssn); chunk_len = sizeof(dp) + data_len; retval = sctp_make_data(asoc, flags, chunk_len, gfp); 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; }

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm15994.08%450.00%
marcelo ricardo leitnermarcelo ricardo leitner52.96%112.50%
david s. millerdavid s. miller31.78%112.50%
ivan skytte jorgensenivan skytte jorgensen10.59%112.50%
vlad yasevichvlad yasevich10.59%112.50%
Total169100.00%8100.00%

/* Create a selective ackowledgement (SACK) for the given * association. This reports on which TSN's we've seen to date, * including duplicates and gaps. */
struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc) { struct sctp_chunk *retval; struct sctp_sackhdr sack; int len; __u32 ctsn; __u16 num_gabs, num_dup_tsns; struct sctp_association *aptr = (struct sctp_association *)asoc; struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map; struct sctp_gap_ack_block gabs[SCTP_MAX_GABS]; struct sctp_transport *trans; memset(gabs, 0, sizeof(gabs)); ctsn = sctp_tsnmap_get_ctsn(map); pr_debug("%s: sackCTSNAck sent:0x%x\n", __func__, ctsn); /* How much room is needed in the chunk? */ num_gabs = sctp_tsnmap_num_gabs(map, gabs); num_dup_tsns = sctp_tsnmap_num_dups(map); /* Initialize the SACK header. */ sack.cum_tsn_ack = htonl(ctsn); sack.a_rwnd = htonl(asoc->a_rwnd); sack.num_gap_ack_blocks = htons(num_gabs); sack.num_dup_tsns = htons(num_dup_tsns); len = sizeof(sack) + sizeof(struct sctp_gap_ack_block) * num_gabs + sizeof(__u32) * num_dup_tsns; /* Create the chunk. */ retval = sctp_make_control(asoc, SCTP_CID_SACK, 0, len, GFP_ATOMIC); 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, gabs); /* Add the duplicate TSN information. */ if (num_dup_tsns) { aptr->stats.idupchunks += num_dup_tsns; sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns, sctp_tsnmap_get_dups(map)); } /* 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; } nodata: return retval; }

Contributors

PersonTokensPropCommitsCommitProp
jon grimmjon grimm23070.55%750.00%
neil hormanneil horman5316.26%17.14%
vladislav yasevichvladislav yasevich226.75%17.14%
michele baldessarimichele baldessari103.07%17.14%
david s. millerdavid s. miller41.23%17.14%
daniel borkmanndaniel borkmann41.23%17.14%
marcelo ricardo leitnermarcelo ricardo leitner20.61%17.14%
vlad yasevichvlad yasevich10.31%17.14%
Total326100.00%14100.00%

/* Make a SHUTDOWN chunk. */
struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc, const struct sctp_chunk *chunk) { struct sctp_chunk *retval; sctp_shutdownhdr_t shut; __u32 ctsn; ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map); shut