440 lines
16 KiB
C
440 lines
16 KiB
C
|
/* SCTP kernel implementation
|
||
|
* (C) Copyright IBM Corp. 2001, 2004
|
||
|
* Copyright (c) 1999-2000 Cisco, Inc.
|
||
|
* Copyright (c) 1999-2001 Motorola, Inc.
|
||
|
* Copyright (c) 2001 Intel Corp.
|
||
|
*
|
||
|
* This file is part of the SCTP kernel implementation
|
||
|
*
|
||
|
* These are definitions needed by the state machine.
|
||
|
*
|
||
|
* 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 addresses:
|
||
|
* 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>
|
||
|
* Xingang Guo <xingang.guo@intel.com>
|
||
|
* Jon Grimm <jgrimm@us.ibm.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>
|
||
|
*/
|
||
|
|
||
|
#include <linux/types.h>
|
||
|
#include <linux/compiler.h>
|
||
|
#include <linux/slab.h>
|
||
|
#include <linux/in.h>
|
||
|
#include <net/sctp/command.h>
|
||
|
#include <net/sctp/sctp.h>
|
||
|
|
||
|
#ifndef __sctp_sm_h__
|
||
|
#define __sctp_sm_h__
|
||
|
|
||
|
/*
|
||
|
* Possible values for the disposition are:
|
||
|
*/
|
||
|
enum sctp_disposition {
|
||
|
SCTP_DISPOSITION_DISCARD, /* No further processing. */
|
||
|
SCTP_DISPOSITION_CONSUME, /* Process return values normally. */
|
||
|
SCTP_DISPOSITION_NOMEM, /* We ran out of memory--recover. */
|
||
|
SCTP_DISPOSITION_DELETE_TCB, /* Close the association. */
|
||
|
SCTP_DISPOSITION_ABORT, /* Close the association NOW. */
|
||
|
SCTP_DISPOSITION_VIOLATION, /* The peer is misbehaving. */
|
||
|
SCTP_DISPOSITION_NOT_IMPL, /* This entry is not implemented. */
|
||
|
SCTP_DISPOSITION_ERROR, /* This is plain old user error. */
|
||
|
SCTP_DISPOSITION_BUG, /* This is a bug. */
|
||
|
};
|
||
|
|
||
|
typedef enum sctp_disposition (sctp_state_fn_t) (
|
||
|
struct net *net,
|
||
|
const struct sctp_endpoint *ep,
|
||
|
const struct sctp_association *asoc,
|
||
|
const union sctp_subtype type,
|
||
|
void *arg,
|
||
|
struct sctp_cmd_seq *commands);
|
||
|
typedef void (sctp_timer_event_t) (struct timer_list *);
|
||
|
struct sctp_sm_table_entry {
|
||
|
sctp_state_fn_t *fn;
|
||
|
const char *name;
|
||
|
};
|
||
|
|
||
|
/* A naming convention of "sctp_sf_xxx" applies to all the state functions
|
||
|
* currently in use.
|
||
|
*/
|
||
|
|
||
|
/* Prototypes for generic state functions. */
|
||
|
sctp_state_fn_t sctp_sf_not_impl;
|
||
|
sctp_state_fn_t sctp_sf_bug;
|
||
|
|
||
|
/* Prototypes for gener timer state functions. */
|
||
|
sctp_state_fn_t sctp_sf_timer_ignore;
|
||
|
|
||
|
/* Prototypes for chunk state functions. */
|
||
|
sctp_state_fn_t sctp_sf_do_9_1_abort;
|
||
|
sctp_state_fn_t sctp_sf_cookie_wait_abort;
|
||
|
sctp_state_fn_t sctp_sf_cookie_echoed_abort;
|
||
|
sctp_state_fn_t sctp_sf_shutdown_pending_abort;
|
||
|
sctp_state_fn_t sctp_sf_shutdown_sent_abort;
|
||
|
sctp_state_fn_t sctp_sf_shutdown_ack_sent_abort;
|
||
|
sctp_state_fn_t sctp_sf_do_5_1B_init;
|
||
|
sctp_state_fn_t sctp_sf_do_5_1C_ack;
|
||
|
sctp_state_fn_t sctp_sf_do_5_1D_ce;
|
||
|
sctp_state_fn_t sctp_sf_do_5_1E_ca;
|
||
|
sctp_state_fn_t sctp_sf_do_4_C;
|
||
|
sctp_state_fn_t sctp_sf_eat_data_6_2;
|
||
|
sctp_state_fn_t sctp_sf_eat_data_fast_4_4;
|
||
|
sctp_state_fn_t sctp_sf_eat_sack_6_2;
|
||
|
sctp_state_fn_t sctp_sf_operr_notify;
|
||
|
sctp_state_fn_t sctp_sf_t1_init_timer_expire;
|
||
|
sctp_state_fn_t sctp_sf_t1_cookie_timer_expire;
|
||
|
sctp_state_fn_t sctp_sf_t2_timer_expire;
|
||
|
sctp_state_fn_t sctp_sf_t4_timer_expire;
|
||
|
sctp_state_fn_t sctp_sf_t5_timer_expire;
|
||
|
sctp_state_fn_t sctp_sf_sendbeat_8_3;
|
||
|
sctp_state_fn_t sctp_sf_beat_8_3;
|
||
|
sctp_state_fn_t sctp_sf_backbeat_8_3;
|
||
|
sctp_state_fn_t sctp_sf_do_9_2_final;
|
||
|
sctp_state_fn_t sctp_sf_do_9_2_shutdown;
|
||
|
sctp_state_fn_t sctp_sf_do_9_2_shut_ctsn;
|
||
|
sctp_state_fn_t sctp_sf_do_ecn_cwr;
|
||
|
sctp_state_fn_t sctp_sf_do_ecne;
|
||
|
sctp_state_fn_t sctp_sf_ootb;
|
||
|
sctp_state_fn_t sctp_sf_pdiscard;
|
||
|
sctp_state_fn_t sctp_sf_violation;
|
||
|
sctp_state_fn_t sctp_sf_discard_chunk;
|
||
|
sctp_state_fn_t sctp_sf_do_5_2_1_siminit;
|
||
|
sctp_state_fn_t sctp_sf_do_5_2_2_dupinit;
|
||
|
sctp_state_fn_t sctp_sf_do_5_2_3_initack;
|
||
|
sctp_state_fn_t sctp_sf_do_5_2_4_dupcook;
|
||
|
sctp_state_fn_t sctp_sf_unk_chunk;
|
||
|
sctp_state_fn_t sctp_sf_do_8_5_1_E_sa;
|
||
|
sctp_state_fn_t sctp_sf_cookie_echoed_err;
|
||
|
sctp_state_fn_t sctp_sf_do_asconf;
|
||
|
sctp_state_fn_t sctp_sf_do_asconf_ack;
|
||
|
sctp_state_fn_t sctp_sf_do_reconf;
|
||
|
sctp_state_fn_t sctp_sf_do_9_2_reshutack;
|
||
|
sctp_state_fn_t sctp_sf_eat_fwd_tsn;
|
||
|
sctp_state_fn_t sctp_sf_eat_fwd_tsn_fast;
|
||
|
sctp_state_fn_t sctp_sf_eat_auth;
|
||
|
|
||
|
/* Prototypes for primitive event state functions. */
|
||
|
sctp_state_fn_t sctp_sf_do_prm_asoc;
|
||
|
sctp_state_fn_t sctp_sf_do_prm_send;
|
||
|
sctp_state_fn_t sctp_sf_do_9_2_prm_shutdown;
|
||
|
sctp_state_fn_t sctp_sf_cookie_wait_prm_shutdown;
|
||
|
sctp_state_fn_t sctp_sf_cookie_echoed_prm_shutdown;
|
||
|
sctp_state_fn_t sctp_sf_do_9_1_prm_abort;
|
||
|
sctp_state_fn_t sctp_sf_cookie_wait_prm_abort;
|
||
|
sctp_state_fn_t sctp_sf_cookie_echoed_prm_abort;
|
||
|
sctp_state_fn_t sctp_sf_shutdown_pending_prm_abort;
|
||
|
sctp_state_fn_t sctp_sf_shutdown_sent_prm_abort;
|
||
|
sctp_state_fn_t sctp_sf_shutdown_ack_sent_prm_abort;
|
||
|
sctp_state_fn_t sctp_sf_error_closed;
|
||
|
sctp_state_fn_t sctp_sf_error_shutdown;
|
||
|
sctp_state_fn_t sctp_sf_ignore_primitive;
|
||
|
sctp_state_fn_t sctp_sf_do_prm_requestheartbeat;
|
||
|
sctp_state_fn_t sctp_sf_do_prm_asconf;
|
||
|
sctp_state_fn_t sctp_sf_do_prm_reconf;
|
||
|
|
||
|
/* Prototypes for other event state functions. */
|
||
|
sctp_state_fn_t sctp_sf_do_no_pending_tsn;
|
||
|
sctp_state_fn_t sctp_sf_do_9_2_start_shutdown;
|
||
|
sctp_state_fn_t sctp_sf_do_9_2_shutdown_ack;
|
||
|
sctp_state_fn_t sctp_sf_ignore_other;
|
||
|
sctp_state_fn_t sctp_sf_cookie_wait_icmp_abort;
|
||
|
|
||
|
/* Prototypes for timeout event state functions. */
|
||
|
sctp_state_fn_t sctp_sf_do_6_3_3_rtx;
|
||
|
sctp_state_fn_t sctp_sf_send_reconf;
|
||
|
sctp_state_fn_t sctp_sf_do_6_2_sack;
|
||
|
sctp_state_fn_t sctp_sf_autoclose_timer_expire;
|
||
|
|
||
|
/* Prototypes for utility support functions. */
|
||
|
__u8 sctp_get_chunk_type(struct sctp_chunk *chunk);
|
||
|
const struct sctp_sm_table_entry *sctp_sm_lookup_event(
|
||
|
struct net *net,
|
||
|
enum sctp_event event_type,
|
||
|
enum sctp_state state,
|
||
|
union sctp_subtype event_subtype);
|
||
|
int sctp_chunk_iif(const struct sctp_chunk *);
|
||
|
struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *,
|
||
|
struct sctp_chunk *,
|
||
|
gfp_t gfp);
|
||
|
__u32 sctp_generate_verification_tag(void);
|
||
|
void sctp_populate_tie_tags(__u8 *cookie, __u32 curTag, __u32 hisTag);
|
||
|
|
||
|
/* Prototypes for chunk-building functions. */
|
||
|
struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,
|
||
|
const struct sctp_bind_addr *bp,
|
||
|
gfp_t gfp, int vparam_len);
|
||
|
struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
|
||
|
const struct sctp_chunk *chunk,
|
||
|
const gfp_t gfp, const int unkparam_len);
|
||
|
struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc,
|
||
|
const struct sctp_chunk *chunk);
|
||
|
struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc,
|
||
|
const struct sctp_chunk *chunk);
|
||
|
struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc,
|
||
|
const __u32 lowest_tsn,
|
||
|
const struct sctp_chunk *chunk);
|
||
|
struct sctp_chunk *sctp_make_idata(const struct sctp_association *asoc,
|
||
|
__u8 flags, int paylen, gfp_t gfp);
|
||
|
struct sctp_chunk *sctp_make_ifwdtsn(const struct sctp_association *asoc,
|
||
|
__u32 new_cum_tsn, size_t nstreams,
|
||
|
struct sctp_ifwdtsn_skip *skiplist);
|
||
|
struct sctp_chunk *sctp_make_datafrag_empty(const struct sctp_association *asoc,
|
||
|
const struct sctp_sndrcvinfo *sinfo,
|
||
|
int len, __u8 flags, gfp_t gfp);
|
||
|
struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc,
|
||
|
const __u32 lowest_tsn);
|
||
|
struct sctp_chunk *sctp_make_sack(struct sctp_association *asoc);
|
||
|
struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
|
||
|
const struct sctp_chunk *chunk);
|
||
|
struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
|
||
|
const struct sctp_chunk *chunk);
|
||
|
struct sctp_chunk *sctp_make_shutdown_complete(
|
||
|
const struct sctp_association *asoc,
|
||
|
const struct sctp_chunk *chunk);
|
||
|
int sctp_init_cause(struct sctp_chunk *chunk, __be16 cause, size_t paylen);
|
||
|
struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc,
|
||
|
const struct sctp_chunk *chunk,
|
||
|
const size_t hint);
|
||
|
struct sctp_chunk *sctp_make_abort_no_data(const struct sctp_association *asoc,
|
||
|
const struct sctp_chunk *chunk,
|
||
|
__u32 tsn);
|
||
|
struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc,
|
||
|
struct msghdr *msg, size_t msg_len);
|
||
|
struct sctp_chunk *sctp_make_abort_violation(
|
||
|
const struct sctp_association *asoc,
|
||
|
const struct sctp_chunk *chunk,
|
||
|
const __u8 *payload,
|
||
|
const size_t paylen);
|
||
|
struct sctp_chunk *sctp_make_violation_paramlen(
|
||
|
const struct sctp_association *asoc,
|
||
|
const struct sctp_chunk *chunk,
|
||
|
struct sctp_paramhdr *param);
|
||
|
struct sctp_chunk *sctp_make_violation_max_retrans(
|
||
|
const struct sctp_association *asoc,
|
||
|
const struct sctp_chunk *chunk);
|
||
|
struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc,
|
||
|
const struct sctp_transport *transport);
|
||
|
struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc,
|
||
|
const struct sctp_chunk *chunk,
|
||
|
const void *payload,
|
||
|
const size_t paylen);
|
||
|
struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc,
|
||
|
const struct sctp_chunk *chunk,
|
||
|
__be16 cause_code, const void *payload,
|
||
|
size_t paylen, size_t reserve_tail);
|
||
|
|
||
|
struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc,
|
||
|
union sctp_addr *laddr,
|
||
|
struct sockaddr *addrs,
|
||
|
int addrcnt, __be16 flags);
|
||
|
struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
|
||
|
union sctp_addr *addr);
|
||
|
bool sctp_verify_asconf(const struct sctp_association *asoc,
|
||
|
struct sctp_chunk *chunk, bool addr_param_needed,
|
||
|
struct sctp_paramhdr **errp);
|
||
|
struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
|
||
|
struct sctp_chunk *asconf);
|
||
|
int sctp_process_asconf_ack(struct sctp_association *asoc,
|
||
|
struct sctp_chunk *asconf_ack);
|
||
|
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 *sctp_make_auth(const struct sctp_association *asoc,
|
||
|
__u16 key_id);
|
||
|
struct sctp_chunk *sctp_make_strreset_req(const struct sctp_association *asoc,
|
||
|
__u16 stream_num, __be16 *stream_list,
|
||
|
bool out, bool in);
|
||
|
struct sctp_chunk *sctp_make_strreset_tsnreq(
|
||
|
const struct sctp_association *asoc);
|
||
|
struct sctp_chunk *sctp_make_strreset_addstrm(
|
||
|
const struct sctp_association *asoc,
|
||
|
__u16 out, __u16 in);
|
||
|
struct sctp_chunk *sctp_make_strreset_resp(const struct sctp_association *asoc,
|
||
|
__u32 result, __u32 sn);
|
||
|
struct sctp_chunk *sctp_make_strreset_tsnresp(struct sctp_association *asoc,
|
||
|
__u32 result, __u32 sn,
|
||
|
__u32 sender_tsn,
|
||
|
__u32 receiver_tsn);
|
||
|
bool sctp_verify_reconf(const struct sctp_association *asoc,
|
||
|
struct sctp_chunk *chunk,
|
||
|
struct sctp_paramhdr **errp);
|
||
|
void sctp_chunk_assign_tsn(struct sctp_chunk *chunk);
|
||
|
void sctp_chunk_assign_ssn(struct sctp_chunk *chunk);
|
||
|
|
||
|
/* Prototypes for stream-processing functions. */
|
||
|
struct sctp_chunk *sctp_process_strreset_outreq(
|
||
|
struct sctp_association *asoc,
|
||
|
union sctp_params param,
|
||
|
struct sctp_ulpevent **evp);
|
||
|
struct sctp_chunk *sctp_process_strreset_inreq(
|
||
|
struct sctp_association *asoc,
|
||
|
union sctp_params param,
|
||
|
struct sctp_ulpevent **evp);
|
||
|
struct sctp_chunk *sctp_process_strreset_tsnreq(
|
||
|
struct sctp_association *asoc,
|
||
|
union sctp_params param,
|
||
|
struct sctp_ulpevent **evp);
|
||
|
struct sctp_chunk *sctp_process_strreset_addstrm_out(
|
||
|
struct sctp_association *asoc,
|
||
|
union sctp_params param,
|
||
|
struct sctp_ulpevent **evp);
|
||
|
struct sctp_chunk *sctp_process_strreset_addstrm_in(
|
||
|
struct sctp_association *asoc,
|
||
|
union sctp_params param,
|
||
|
struct sctp_ulpevent **evp);
|
||
|
struct sctp_chunk *sctp_process_strreset_resp(
|
||
|
struct sctp_association *asoc,
|
||
|
union sctp_params param,
|
||
|
struct sctp_ulpevent **evp);
|
||
|
|
||
|
/* Prototypes for statetable processing. */
|
||
|
|
||
|
int sctp_do_sm(struct net *net, enum sctp_event event_type,
|
||
|
union sctp_subtype subtype, enum sctp_state state,
|
||
|
struct sctp_endpoint *ep, struct sctp_association *asoc,
|
||
|
void *event_arg, gfp_t gfp);
|
||
|
|
||
|
/* 2nd level prototypes */
|
||
|
void sctp_generate_t3_rtx_event(struct timer_list *t);
|
||
|
void sctp_generate_heartbeat_event(struct timer_list *t);
|
||
|
void sctp_generate_reconf_event(struct timer_list *t);
|
||
|
void sctp_generate_proto_unreach_event(struct timer_list *t);
|
||
|
|
||
|
void sctp_ootb_pkt_free(struct sctp_packet *packet);
|
||
|
|
||
|
struct sctp_association *sctp_unpack_cookie(
|
||
|
const struct sctp_endpoint *ep,
|
||
|
const struct sctp_association *asoc,
|
||
|
struct sctp_chunk *chunk,
|
||
|
gfp_t gfp, int *err,
|
||
|
struct sctp_chunk **err_chk_p);
|
||
|
|
||
|
/* 3rd level prototypes */
|
||
|
__u32 sctp_generate_tag(const struct sctp_endpoint *ep);
|
||
|
__u32 sctp_generate_tsn(const struct sctp_endpoint *ep);
|
||
|
|
||
|
/* Extern declarations for major data structures. */
|
||
|
extern sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES];
|
||
|
|
||
|
|
||
|
/* Get the size of a DATA chunk payload. */
|
||
|
static inline __u16 sctp_data_size(struct sctp_chunk *chunk)
|
||
|
{
|
||
|
__u16 size;
|
||
|
|
||
|
size = ntohs(chunk->chunk_hdr->length);
|
||
|
size -= sctp_datachk_len(&chunk->asoc->stream);
|
||
|
|
||
|
return size;
|
||
|
}
|
||
|
|
||
|
/* Compare two TSNs */
|
||
|
#define TSN_lt(a,b) \
|
||
|
(typecheck(__u32, a) && \
|
||
|
typecheck(__u32, b) && \
|
||
|
((__s32)((a) - (b)) < 0))
|
||
|
|
||
|
#define TSN_lte(a,b) \
|
||
|
(typecheck(__u32, a) && \
|
||
|
typecheck(__u32, b) && \
|
||
|
((__s32)((a) - (b)) <= 0))
|
||
|
|
||
|
/* Compare two MIDs */
|
||
|
#define MID_lt(a, b) \
|
||
|
(typecheck(__u32, a) && \
|
||
|
typecheck(__u32, b) && \
|
||
|
((__s32)((a) - (b)) < 0))
|
||
|
|
||
|
/* Compare two SSNs */
|
||
|
#define SSN_lt(a,b) \
|
||
|
(typecheck(__u16, a) && \
|
||
|
typecheck(__u16, b) && \
|
||
|
((__s16)((a) - (b)) < 0))
|
||
|
|
||
|
/* ADDIP 3.1.1 */
|
||
|
#define ADDIP_SERIAL_gte(a,b) \
|
||
|
(typecheck(__u32, a) && \
|
||
|
typecheck(__u32, b) && \
|
||
|
((__s32)((b) - (a)) <= 0))
|
||
|
|
||
|
/* Check VTAG of the packet matches the sender's own tag. */
|
||
|
static inline int
|
||
|
sctp_vtag_verify(const struct sctp_chunk *chunk,
|
||
|
const struct sctp_association *asoc)
|
||
|
{
|
||
|
/* RFC 2960 Sec 8.5 When receiving an SCTP packet, the endpoint
|
||
|
* MUST ensure that the value in the Verification Tag field of
|
||
|
* the received SCTP packet matches its own Tag. If the received
|
||
|
* Verification Tag value does not match the receiver's own
|
||
|
* tag value, the receiver shall silently discard the packet...
|
||
|
*/
|
||
|
if (ntohl(chunk->sctp_hdr->vtag) == asoc->c.my_vtag)
|
||
|
return 1;
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
/* Check VTAG of the packet matches the sender's own tag and the T bit is
|
||
|
* not set, OR its peer's tag and the T bit is set in the Chunk Flags.
|
||
|
*/
|
||
|
static inline int
|
||
|
sctp_vtag_verify_either(const struct sctp_chunk *chunk,
|
||
|
const struct sctp_association *asoc)
|
||
|
{
|
||
|
/* RFC 2960 Section 8.5.1, sctpimpguide Section 2.41
|
||
|
*
|
||
|
* B) The receiver of a ABORT MUST accept the packet
|
||
|
* if the Verification Tag field of the packet matches its own tag
|
||
|
* and the T bit is not set
|
||
|
* OR
|
||
|
* it is set to its peer's tag and the T bit is set in the Chunk
|
||
|
* Flags.
|
||
|
* Otherwise, the receiver MUST silently discard the packet
|
||
|
* and take no further action.
|
||
|
*
|
||
|
* C) The receiver of a SHUTDOWN COMPLETE shall accept the packet
|
||
|
* if the Verification Tag field of the packet matches its own tag
|
||
|
* and the T bit is not set
|
||
|
* OR
|
||
|
* it is set to its peer's tag and the T bit is set in the Chunk
|
||
|
* Flags.
|
||
|
* Otherwise, the receiver MUST silently discard the packet
|
||
|
* and take no further action. An endpoint MUST ignore the
|
||
|
* SHUTDOWN COMPLETE if it is not in the SHUTDOWN-ACK-SENT state.
|
||
|
*/
|
||
|
if ((!sctp_test_T_bit(chunk) &&
|
||
|
(ntohl(chunk->sctp_hdr->vtag) == asoc->c.my_vtag)) ||
|
||
|
(sctp_test_T_bit(chunk) && asoc->c.peer_vtag &&
|
||
|
(ntohl(chunk->sctp_hdr->vtag) == asoc->c.peer_vtag))) {
|
||
|
return 1;
|
||
|
}
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
#endif /* __sctp_sm_h__ */
|