/* 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 *, const 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__ */