/* SPDX-License-Identifier: GPL-2.0-or-later */ /* 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. * * Please send any bug reports or fixes you make to the * email addresses: * lksctp developers * * Written or modified by: * La Monte H.P. Yarroll * Karl Knutson * Xingang Guo * Jon Grimm * Dajiang Zhang * Sridhar Samudrala * Daisy Chang * Ardelle Fan * Kevin Gao */ #include #include #include #include #include #include #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_type 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_type 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__ */