/* 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:
*/
typedef enum {
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. */
} sctp_disposition_t;
typedef struct {
int name;
int action;
} sctp_sm_command_t;
typedef sctp_disposition_t (sctp_state_fn_t) (struct net *,
const struct sctp_endpoint *,
const struct sctp_association *,
const sctp_subtype_t type,
void *arg,
sctp_cmd_seq_t *);
typedef void (sctp_timer_event_t) (unsigned long);
typedef struct {
sctp_state_fn_t *fn;
const char *name;
} sctp_sm_table_entry_t;
/* 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_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;
/* 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_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 sctp_sm_table_entry_t *sctp_sm_lookup_event(struct net *,
sctp_event_t,
sctp_state_t,
sctp_subtype_t);
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 *,
const struct sctp_bind_addr *,
gfp_t gfp, int vparam_len);
struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *,
const struct sctp_chunk *,
const gfp_t gfp,
const int unkparam_len);
struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *,
const struct sctp_chunk *);
struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *,
const struct sctp_chunk *);
struct sctp_chunk *sctp_make_cwr(const struct sctp_association *,
const __u32 lowest_tsn,
const struct sctp_chunk *);
struct sctp_chunk * sctp_make_datafrag_empty(struct sctp_association *,
const struct sctp_sndrcvinfo *sinfo,
int len, const __u8 flags,
__u16 ssn);
struct sctp_chunk *sctp_make_ecne(const struct sctp_association *,
const __u32);
struct sctp_chunk *sctp_make_sack(const struct sctp_association *);
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 *);
struct sctp_chunk *sctp_make_shutdown_complete(const struct sctp_association *,
const struct sctp_chunk *);
void sctp_init_cause(struct sctp_chunk *, __be16 cause, size_t);
struct sctp_chunk *sctp_make_abort(const struct sctp_association *,
const struct sctp_chunk *,
const size_t hint);
struct sctp_chunk *sctp_make_abort_no_data(const struct sctp_association *,
const struct sctp_chunk *,
__u32 tsn);
struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *,
struct msghdr *, size_t msg_len);
struct sctp_chunk *sctp_make_abort_violation(const struct sctp_association *,
const struct sctp_chunk *,
const __u8 *,
const size_t );
struct sctp_chunk *sctp_make_violation_paramlen(const struct sctp_association *,
const struct sctp_chunk *,
struct sctp_paramhdr *);
struct sctp_chunk *sctp_make_violation_max_retrans(const struct sctp_association *,
const struct sctp_chunk *);
struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *,
const struct sctp_transport *);
struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *,
const struct sctp_chunk *,
const void *payload,
const size_t paylen);
struct sctp_chunk *sctp_make_op_error(const struct sctp_association *,
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 *,
union sctp_addr *,
struct sockaddr *,
int, __be16);
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);
void sctp_chunk_assign_tsn(struct sctp_chunk *);
void sctp_chunk_assign_ssn(struct sctp_chunk *);
/* Prototypes for statetable processing. */
int sctp_do_sm(struct net *net, sctp_event_t event_type, sctp_subtype_t subtype,
sctp_state_t state,
struct sctp_endpoint *,
struct sctp_association *asoc,
void *event_arg,
gfp_t gfp);
/* 2nd level prototypes */
void sctp_generate_t3_rtx_event(unsigned long peer);
void sctp_generate_heartbeat_event(unsigned long peer);
void sctp_generate_proto_unreach_event(unsigned long peer);
void sctp_ootb_pkt_free(struct sctp_packet *);
struct sctp_association *sctp_unpack_cookie(const struct sctp_endpoint *,
const struct sctp_association *,
struct sctp_chunk *,
gfp_t gfp, int *err,
struct sctp_chunk **err_chk_p);
int sctp_addip_addr_config(struct sctp_association *, sctp_param_t,
struct sockaddr_storage*, int);
/* 3rd level prototypes */
__u32 sctp_generate_tag(const struct sctp_endpoint *);
__u32 sctp_generate_tsn(const struct sctp_endpoint *);
/* 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 -= sizeof(sctp_data_chunk_t);
return size;
}
/* Compare two TSNs */
/* RFC 1982 - Serial Number Arithmetic
*
* 2. Comparison
* Then, s1 is said to be equal to s2 if and only if i1 is equal to i2,
* in all other cases, s1 is not equal to s2.
*
* s1 is said to be less than s2 if, and only if, s1 is not equal to s2,
* and
*
* (i1 < i2 and i2 - i1 < 2^(SERIAL_BITS - 1)) or
* (i1 > i2 and i1 - i2 > 2^(SERIAL_BITS - 1))
*
* s1 is said to be greater than s2 if, and only if, s1 is not equal to
* s2, and
*
* (i1 < i2 and i2 - i1 > 2^(SERIAL_BITS - 1)) or
* (i1 > i2 and i1 - i2 < 2^(SERIAL_BITS - 1))
*/
/*
* RFC 2960
* 1.6 Serial Number Arithmetic
*
* Comparisons and arithmetic on TSNs in this document SHOULD use Serial
* Number Arithmetic as defined in [RFC1982] where SERIAL_BITS = 32.
*/
enum {
TSN_SIGN_BIT = (1<<31)
};
static inline int TSN_lt(__u32 s, __u32 t)
{
return ((s) - (t)) & TSN_SIGN_BIT;
}
static inline int TSN_lte(__u32 s, __u32 t)
{
return ((s) == (t)) || (((s) - (t)) & TSN_SIGN_BIT);
}
/* Compare two SSNs */
/*
* RFC 2960
* 1.6 Serial Number Arithmetic
*
* Comparisons and arithmetic on Stream Sequence Numbers in this document
* SHOULD use Serial Number Arithmetic as defined in [RFC1982] where
* SERIAL_BITS = 16.
*/
enum {
SSN_SIGN_BIT = (1<<15)
};
static inline int SSN_lt(__u16 s, __u16 t)
{
return ((s) - (t)) & SSN_SIGN_BIT;
}
static inline int SSN_lte(__u16 s, __u16 t)
{
return ((s) == (t)) || (((s) - (t)) & SSN_SIGN_BIT);
}
/*
* ADDIP 3.1.1
* The valid range of Serial Number is from 0 to 4294967295 (2**32 - 1). Serial
* Numbers wrap back to 0 after reaching 4294967295.
*/
enum {
ADDIP_SERIAL_SIGN_BIT = (1<<31)
};
static inline int ADDIP_SERIAL_gte(__u16 s, __u16 t)
{
return ((s) == (t)) || (((t) - (s)) & ADDIP_SERIAL_SIGN_BIT);
}
/* 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__ */