FreeBSD/Linux Kernel Cross Reference
sys/netinet/sctp_structs.h

     /*-
      * Copyright (c) 2001-2008, by Cisco Systems, Inc. All rights reserved.
      * Copyright (c) 2008-2012, by Randall Stewart. All rights reserved.
      * Copyright (c) 2008-2012, by Michael Tuexen. All rights reserved.
      *
      * Redistribution and use in source and binary forms, with or without
      * modification, are permitted provided that the following conditions are met:
      *
      * a) Redistributions of source code must retain the above copyright notice,
     *    this list of conditions and the following disclaimer.
     *
     * b) Redistributions in binary form must reproduce the above copyright
     *    notice, this list of conditions and the following disclaimer in
     *    the documentation and/or other materials provided with the distribution.
     *
     * c) Neither the name of Cisco Systems, Inc. nor the names of its
     *    contributors may be used to endorse or promote products derived
     *    from this software without specific prior written permission.
     *
     * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
     * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
     * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
     * THE POSSIBILITY OF SUCH DAMAGE.
     */
    
    #include <sys/cdefs.h>
    __FBSDID("$FreeBSD: releng/10.1/sys/netinet/sctp_structs.h 271750 2014-09-18 09:49:49Z tuexen $");
    
    #ifndef _NETINET_SCTP_STRUCTS_H_
    #define _NETINET_SCTP_STRUCTS_H_
    
    #include <netinet/sctp_os.h>
    #include <netinet/sctp_header.h>
    #include <netinet/sctp_auth.h>
    
    struct sctp_timer {
            sctp_os_timer_t timer;
    
            int type;
            /*
             * Depending on the timer type these will be setup and cast with the
             * appropriate entity.
             */
            void *ep;
            void *tcb;
            void *net;
            void *vnet;
    
            /* for sanity checking */
            void *self;
            uint32_t ticks;
            uint32_t stopped_from;
    };
    
    
    struct sctp_foo_stuff {
            struct sctp_inpcb *inp;
            uint32_t lineno;
            uint32_t ticks;
            int updown;
    };
    
    
    /*
     * This is the information we track on each interface that we know about from
     * the distant end.
     */
    TAILQ_HEAD(sctpnetlisthead, sctp_nets);
    
    struct sctp_stream_reset_list {
            TAILQ_ENTRY(sctp_stream_reset_list) next_resp;
            uint32_t tsn;
            uint32_t number_entries;
            uint16_t list_of_streams[];
    };
    
    TAILQ_HEAD(sctp_resethead, sctp_stream_reset_list);
    
    /*
     * Users of the iterator need to malloc a iterator with a call to
     * sctp_initiate_iterator(inp_func, assoc_func, inp_func,  pcb_flags, pcb_features,
     *     asoc_state, void-ptr-arg, uint32-arg, end_func, inp);
     *
     * Use the following two defines if you don't care what pcb flags are on the EP
     * and/or you don't care what state the association is in.
     *
     * Note that if you specify an INP as the last argument then ONLY each
     * association of that single INP will be executed upon. Note that the pcb
     * flags STILL apply so if the inp you specify has different pcb_flags then
     * what you put in pcb_flags nothing will happen. use SCTP_PCB_ANY_FLAGS to
     * assure the inp you specify gets treated.
     */
   #define SCTP_PCB_ANY_FLAGS      0x00000000
   #define SCTP_PCB_ANY_FEATURES   0x00000000
   #define SCTP_ASOC_ANY_STATE     0x00000000
   
   typedef void (*asoc_func) (struct sctp_inpcb *, struct sctp_tcb *, void *ptr,
            uint32_t val);
   typedef int (*inp_func) (struct sctp_inpcb *, void *ptr, uint32_t val);
   typedef void (*end_func) (void *ptr, uint32_t val);
   
   #if defined(__FreeBSD__) && defined(SCTP_MCORE_INPUT) && defined(SMP)
   /* whats on the mcore control struct */
   struct sctp_mcore_queue {
           TAILQ_ENTRY(sctp_mcore_queue) next;
           struct vnet *vn;
           struct mbuf *m;
           int off;
           int v6;
   };
   
   TAILQ_HEAD(sctp_mcore_qhead, sctp_mcore_queue);
   
   struct sctp_mcore_ctrl {
           SCTP_PROCESS_STRUCT thread_proc;
           struct sctp_mcore_qhead que;
           struct mtx core_mtx;
           struct mtx que_mtx;
           int running;
           int cpuid;
   };
   
   
   #endif
   
   
   struct sctp_iterator {
           TAILQ_ENTRY(sctp_iterator) sctp_nxt_itr;
           struct vnet *vn;
           struct sctp_timer tmr;
           struct sctp_inpcb *inp; /* current endpoint */
           struct sctp_tcb *stcb;  /* current* assoc */
           struct sctp_inpcb *next_inp;    /* special hook to skip to */
           asoc_func function_assoc;       /* per assoc function */
           inp_func function_inp;  /* per endpoint function */
           inp_func function_inp_end;      /* end INP function */
           end_func function_atend;/* iterator completion function */
           void *pointer;          /* pointer for apply func to use */
           uint32_t val;           /* value for apply func to use */
           uint32_t pcb_flags;     /* endpoint flags being checked */
           uint32_t pcb_features;  /* endpoint features being checked */
           uint32_t asoc_state;    /* assoc state being checked */
           uint32_t iterator_flags;
           uint8_t no_chunk_output;
           uint8_t done_current_ep;
   };
   
   /* iterator_flags values */
   #define SCTP_ITERATOR_DO_ALL_INP        0x00000001
   #define SCTP_ITERATOR_DO_SINGLE_INP     0x00000002
   
   
   TAILQ_HEAD(sctpiterators, sctp_iterator);
   
   struct sctp_copy_all {
           struct sctp_inpcb *inp; /* ep */
           struct mbuf *m;
           struct sctp_sndrcvinfo sndrcv;
           int sndlen;
           int cnt_sent;
           int cnt_failed;
   };
   
   struct sctp_asconf_iterator {
           struct sctpladdr list_of_work;
           int cnt;
   };
   
   struct iterator_control {
           struct mtx ipi_iterator_wq_mtx;
           struct mtx it_mtx;
           SCTP_PROCESS_STRUCT thread_proc;
           struct sctpiterators iteratorhead;
           struct sctp_iterator *cur_it;
           uint32_t iterator_running;
           uint32_t iterator_flags;
   };
   
   #define SCTP_ITERATOR_STOP_CUR_IT       0x00000004
   #define SCTP_ITERATOR_STOP_CUR_INP      0x00000008
   
   struct sctp_net_route {
           sctp_rtentry_t *ro_rt;
           void *ro_lle;
           void *ro_ia;
           int ro_flags;
           union sctp_sockstore _l_addr;   /* remote peer addr */
           struct sctp_ifa *_s_addr;       /* our selected src addr */
   };
   
   struct htcp {
           uint16_t alpha;         /* Fixed point arith, << 7 */
           uint8_t beta;           /* Fixed point arith, << 7 */
           uint8_t modeswitch;     /* Delay modeswitch until we had at least one
                                    * congestion event */
           uint32_t last_cong;     /* Time since last congestion event end */
           uint32_t undo_last_cong;
           uint16_t bytes_acked;
           uint32_t bytecount;
           uint32_t minRTT;
           uint32_t maxRTT;
   
           uint32_t undo_maxRTT;
           uint32_t undo_old_maxB;
   
           /* Bandwidth estimation */
           uint32_t minB;
           uint32_t maxB;
           uint32_t old_maxB;
           uint32_t Bi;
           uint32_t lasttime;
   };
   
   struct rtcc_cc {
           struct timeval tls;     /* The time we started the sending  */
           uint64_t lbw;           /* Our last estimated bw */
           uint64_t lbw_rtt;       /* RTT at bw estimate */
           uint64_t bw_bytes;      /* The total bytes since this sending began */
           uint64_t bw_tot_time;   /* The total time since sending began */
           uint64_t new_tot_time;  /* temp holding the new value */
           uint64_t bw_bytes_at_last_rttc; /* What bw_bytes was at last rtt calc */
           uint32_t cwnd_at_bw_set;/* Cwnd at last bw saved - lbw */
           uint32_t vol_reduce;    /* cnt of voluntary reductions */
           uint16_t steady_step;   /* The number required to be in steady state */
           uint16_t step_cnt;      /* The current number */
           uint8_t ret_from_eq;    /* When all things are equal what do I return
                                    * 0/1 - 1 no cc advance */
           uint8_t use_dccc_ecn;   /* Flag to enable DCCC ECN */
           uint8_t tls_needs_set;  /* Flag to indicate we need to set tls 0 or 1
                                    * means set at send 2 not */
           uint8_t last_step_state;/* Last state if steady state stepdown is on */
           uint8_t rtt_set_this_sack;      /* Flag saying this sack had RTT calc
                                            * on it */
           uint8_t last_inst_ind;  /* Last saved inst indication */
   };
   
   
   struct sctp_nets {
           TAILQ_ENTRY(sctp_nets) sctp_next;       /* next link */
   
           /*
            * Things on the top half may be able to be split into a common
            * structure shared by all.
            */
           struct sctp_timer pmtu_timer;
           struct sctp_timer hb_timer;
   
           /*
            * The following two in combination equate to a route entry for v6
            * or v4.
            */
           struct sctp_net_route ro;
   
           /* mtu discovered so far */
           uint32_t mtu;
           uint32_t ssthresh;      /* not sure about this one for split */
           uint32_t last_cwr_tsn;
           uint32_t cwr_window_tsn;
           uint32_t ecn_ce_pkt_cnt;
           uint32_t lost_cnt;
           /* smoothed average things for RTT and RTO itself */
           int lastsa;
           int lastsv;
           uint64_t rtt;           /* last measured rtt value in us */
           unsigned int RTO;
   
           /* This is used for SHUTDOWN/SHUTDOWN-ACK/SEND or INIT timers */
           struct sctp_timer rxt_timer;
   
           /* last time in seconds I sent to it */
           struct timeval last_sent_time;
           union cc_control_data {
                   struct htcp htcp_ca;    /* JRS - struct used in HTCP algorithm */
                   struct rtcc_cc rtcc;    /* rtcc module cc stuff  */
           }               cc_mod;
           int ref_count;
   
           /* Congestion stats per destination */
           /*
            * flight size variables and such, sorry Vern, I could not avoid
            * this if I wanted performance :>
            */
           uint32_t flight_size;
           uint32_t cwnd;          /* actual cwnd */
           uint32_t prev_cwnd;     /* cwnd before any processing */
           uint32_t ecn_prev_cwnd; /* ECN prev cwnd at first ecn_echo seen in new
                                    * window */
           uint32_t partial_bytes_acked;   /* in CA tracks when to incr a MTU */
           /* tracking variables to avoid the aloc/free in sack processing */
           unsigned int net_ack;
           unsigned int net_ack2;
   
           /*
            * JRS - 5/8/07 - Variable to track last time a destination was
            * active for CMT PF
            */
           uint32_t last_active;
   
           /*
            * CMT variables (iyengar@cis.udel.edu)
            */
           uint32_t this_sack_highest_newack;      /* tracks highest TSN newly
                                                    * acked for a given dest in
                                                    * the current SACK. Used in
                                                    * SFR and HTNA algos */
           uint32_t pseudo_cumack; /* CMT CUC algorithm. Maintains next expected
                                    * pseudo-cumack for this destination */
           uint32_t rtx_pseudo_cumack;     /* CMT CUC algorithm. Maintains next
                                            * expected pseudo-cumack for this
                                            * destination */
   
           /* CMT fast recovery variables */
           uint32_t fast_recovery_tsn;
           uint32_t heartbeat_random1;
           uint32_t heartbeat_random2;
   #ifdef INET6
           uint32_t flowlabel;
   #endif
           uint8_t dscp;
   
           struct timeval start_time;      /* time when this net was created */
           uint32_t marked_retrans;/* number or DATA chunks marked for timer
                                    * based retransmissions */
           uint32_t marked_fastretrans;
           uint32_t heart_beat_delay;      /* Heart Beat delay in ms */
   
           /* if this guy is ok or not ... status */
           uint16_t dest_state;
           /* number of timeouts to consider the destination unreachable */
           uint16_t failure_threshold;
           /* number of timeouts to consider the destination potentially failed */
           uint16_t pf_threshold;
           /* error stats on the destination */
           uint16_t error_count;
           /* UDP port number in case of UDP tunneling */
           uint16_t port;
   
           uint8_t fast_retran_loss_recovery;
           uint8_t will_exit_fast_recovery;
           /* Flags that probably can be combined into dest_state */
           uint8_t fast_retran_ip; /* fast retransmit in progress */
           uint8_t hb_responded;
           uint8_t saw_newack;     /* CMT's SFR algorithm flag */
           uint8_t src_addr_selected;      /* if we split we move */
           uint8_t indx_of_eligible_next_to_use;
           uint8_t addr_is_local;  /* its a local address (if known) could move
                                    * in split */
   
           /*
            * CMT variables (iyengar@cis.udel.edu)
            */
           uint8_t find_pseudo_cumack;     /* CMT CUC algorithm. Flag used to
                                            * find a new pseudocumack. This flag
                                            * is set after a new pseudo-cumack
                                            * has been received and indicates
                                            * that the sender should find the
                                            * next pseudo-cumack expected for
                                            * this destination */
           uint8_t find_rtx_pseudo_cumack; /* CMT CUCv2 algorithm. Flag used to
                                            * find a new rtx-pseudocumack. This
                                            * flag is set after a new
                                            * rtx-pseudo-cumack has been received
                                            * and indicates that the sender
                                            * should find the next
                                            * rtx-pseudo-cumack expected for this
                                            * destination */
           uint8_t new_pseudo_cumack;      /* CMT CUC algorithm. Flag used to
                                            * indicate if a new pseudo-cumack or
                                            * rtx-pseudo-cumack has been received */
           uint8_t window_probe;   /* Doing a window probe? */
           uint8_t RTO_measured;   /* Have we done the first measure */
           uint8_t last_hs_used;   /* index into the last HS table entry we used */
           uint8_t lan_type;
           uint8_t rto_needed;
           uint32_t flowid;
   #ifdef INVARIANTS
           uint8_t flowidset;
   #endif
   };
   
   
   struct sctp_data_chunkrec {
           uint32_t TSN_seq;       /* the TSN of this transmit */
           uint16_t stream_seq;    /* the stream sequence number of this transmit */
           uint16_t stream_number; /* the stream number of this guy */
           uint32_t payloadtype;
           uint32_t context;       /* from send */
           uint32_t cwnd_at_send;
           /*
            * part of the Highest sacked algorithm to be able to stroke counts
            * on ones that are FR'd.
            */
           uint32_t fast_retran_tsn;       /* sending_seq at the time of FR */
           struct timeval timetodrop;      /* time we drop it from queue */
           uint8_t doing_fast_retransmit;
           uint8_t rcv_flags;      /* flags pulled from data chunk on inbound for
                                    * outbound holds sending flags for PR-SCTP. */
           uint8_t state_flags;
           uint8_t chunk_was_revoked;
           uint8_t fwd_tsn_cnt;
   };
   
   TAILQ_HEAD(sctpchunk_listhead, sctp_tmit_chunk);
   
   /* The lower byte is used to enumerate PR_SCTP policies */
   #define CHUNK_FLAGS_PR_SCTP_TTL         SCTP_PR_SCTP_TTL
   #define CHUNK_FLAGS_PR_SCTP_BUF         SCTP_PR_SCTP_BUF
   #define CHUNK_FLAGS_PR_SCTP_RTX         SCTP_PR_SCTP_RTX
   
   /* The upper byte is used as a bit mask */
   #define CHUNK_FLAGS_FRAGMENT_OK         0x0100
   
   struct chk_id {
           uint8_t id;
           uint8_t can_take_data;
   };
   
   
   struct sctp_tmit_chunk {
           union {
                   struct sctp_data_chunkrec data;
                   struct chk_id chunk_id;
           }     rec;
           struct sctp_association *asoc;  /* bp to asoc this belongs to */
           struct timeval sent_rcv_time;   /* filled in if RTT being calculated */
           struct mbuf *data;      /* pointer to mbuf chain of data */
           struct mbuf *last_mbuf; /* pointer to last mbuf in chain */
           struct sctp_nets *whoTo;
                     TAILQ_ENTRY(sctp_tmit_chunk) sctp_next;       /* next link */
           int32_t sent;           /* the send status */
           uint16_t snd_count;     /* number of times I sent */
           uint16_t flags;         /* flags, such as FRAGMENT_OK */
           uint16_t send_size;
           uint16_t book_size;
           uint16_t mbcnt;
           uint16_t auth_keyid;
           uint8_t holds_key_ref;  /* flag if auth keyid refcount is held */
           uint8_t pad_inplace;
           uint8_t do_rtt;
           uint8_t book_size_scale;
           uint8_t no_fr_allowed;
           uint8_t copy_by_ref;
           uint8_t window_probe;
   };
   
   /*
    * The first part of this structure MUST be the entire sinfo structure. Maybe
    * I should have made it a sub structure... we can circle back later and do
    * that if we want.
    */
   struct sctp_queued_to_read {    /* sinfo structure Pluse more */
           uint16_t sinfo_stream;  /* off the wire */
           uint16_t sinfo_ssn;     /* off the wire */
           uint16_t sinfo_flags;   /* SCTP_UNORDERED from wire use SCTP_EOF for
                                    * EOR */
           uint32_t sinfo_ppid;    /* off the wire */
           uint32_t sinfo_context; /* pick this up from assoc def context? */
           uint32_t sinfo_timetolive;      /* not used by kernel */
           uint32_t sinfo_tsn;     /* Use this in reassembly as first TSN */
           uint32_t sinfo_cumtsn;  /* Use this in reassembly as last TSN */
           sctp_assoc_t sinfo_assoc_id;    /* our assoc id */
           /* Non sinfo stuff */
           uint32_t length;        /* length of data */
           uint32_t held_length;   /* length held in sb */
           struct sctp_nets *whoFrom;      /* where it came from */
           struct mbuf *data;      /* front of the mbuf chain of data with
                                    * PKT_HDR */
           struct mbuf *tail_mbuf; /* used for multi-part data */
           struct mbuf *aux_data;  /* used to hold/cache  control if o/s does not
                                    * take it from us */
           struct sctp_tcb *stcb;  /* assoc, used for window update */
                    TAILQ_ENTRY(sctp_queued_to_read) next;
           uint16_t port_from;
           uint16_t spec_flags;    /* Flags to hold the notification field */
           uint8_t do_not_ref_stcb;
           uint8_t end_added;
           uint8_t pdapi_aborted;
           uint8_t some_taken;
   };
   
   /* This data structure will be on the outbound
    * stream queues. Data will be pulled off from
    * the front of the mbuf data and chunk-ified
    * by the output routines. We will custom
    * fit every chunk we pull to the send/sent
    * queue to make up the next full packet
    * if we can. An entry cannot be removed
    * from the stream_out queue until
    * the msg_is_complete flag is set. This
    * means at times data/tail_mbuf MIGHT
    * be NULL.. If that occurs it happens
    * for one of two reasons. Either the user
    * is blocked on a send() call and has not
    * awoken to copy more data down... OR
    * the user is in the explict MSG_EOR mode
    * and wrote some data, but has not completed
    * sending.
    */
   struct sctp_stream_queue_pending {
           struct mbuf *data;
           struct mbuf *tail_mbuf;
           struct timeval ts;
           struct sctp_nets *net;
                     TAILQ_ENTRY(sctp_stream_queue_pending) next;
                     TAILQ_ENTRY(sctp_stream_queue_pending) ss_next;
           uint32_t length;
           uint32_t timetolive;
           uint32_t ppid;
           uint32_t context;
           uint16_t sinfo_flags;
           uint16_t stream;
           uint16_t act_flags;
           uint16_t auth_keyid;
           uint8_t holds_key_ref;
           uint8_t msg_is_complete;
           uint8_t some_taken;
           uint8_t sender_all_done;
           uint8_t put_last_out;
           uint8_t discard_rest;
   };
   
   /*
    * this struct contains info that is used to track inbound stream data and
    * help with ordering.
    */
   TAILQ_HEAD(sctpwheelunrel_listhead, sctp_stream_in);
   struct sctp_stream_in {
           struct sctp_readhead inqueue;
           uint16_t stream_no;
           uint16_t last_sequence_delivered;       /* used for re-order */
           uint8_t delivery_started;
   };
   
   TAILQ_HEAD(sctpwheel_listhead, sctp_stream_out);
   TAILQ_HEAD(sctplist_listhead, sctp_stream_queue_pending);
   
   /* Round-robin schedulers */
   struct ss_rr {
           /* next link in wheel */
           TAILQ_ENTRY(sctp_stream_out) next_spoke;
   };
   
   /* Priority scheduler */
   struct ss_prio {
           /* next link in wheel */
           TAILQ_ENTRY(sctp_stream_out) next_spoke;
           /* priority id */
           uint16_t priority;
   };
   
   /* Fair Bandwidth scheduler */
   struct ss_fb {
           /* next link in wheel */
           TAILQ_ENTRY(sctp_stream_out) next_spoke;
           /* stores message size */
           int32_t rounds;
   };
   
   /*
    * This union holds all data necessary for
    * different stream schedulers.
    */
   union scheduling_data {
           struct sctpwheel_listhead out_wheel;
           struct sctplist_listhead out_list;
   };
   
   /*
    * This union holds all parameters per stream
    * necessary for different stream schedulers.
    */
   union scheduling_parameters {
           struct ss_rr rr;
           struct ss_prio prio;
           struct ss_fb fb;
   };
   
   /* This struct is used to track the traffic on outbound streams */
   struct sctp_stream_out {
           struct sctp_streamhead outqueue;
           union scheduling_parameters ss_params;
           uint32_t chunks_on_queues;
   #if defined(SCTP_DETAILED_STR_STATS)
           uint32_t abandoned_unsent[SCTP_PR_SCTP_MAX + 1];
           uint32_t abandoned_sent[SCTP_PR_SCTP_MAX + 1];
   #else
           /* Only the aggregation */
           uint32_t abandoned_unsent[1];
           uint32_t abandoned_sent[1];
   #endif
           uint16_t stream_no;
           uint16_t next_sequence_send;    /* next one I expect to send out */
           uint8_t last_msg_incomplete;
   };
   
   /* used to keep track of the addresses yet to try to add/delete */
   TAILQ_HEAD(sctp_asconf_addrhead, sctp_asconf_addr);
   struct sctp_asconf_addr {
           TAILQ_ENTRY(sctp_asconf_addr) next;
           struct sctp_asconf_addr_param ap;
           struct sctp_ifa *ifa;   /* save the ifa for add/del ip */
           uint8_t sent;           /* has this been sent yet? */
           uint8_t special_del;    /* not to be used in lookup */
   };
   
   struct sctp_scoping {
           uint8_t ipv4_addr_legal;
           uint8_t ipv6_addr_legal;
           uint8_t loopback_scope;
           uint8_t ipv4_local_scope;
           uint8_t local_scope;
           uint8_t site_scope;
   };
   
   #define SCTP_TSN_LOG_SIZE 40
   
   struct sctp_tsn_log {
           void *stcb;
           uint32_t tsn;
           uint16_t strm;
           uint16_t seq;
           uint16_t sz;
           uint16_t flgs;
           uint16_t in_pos;
           uint16_t in_out;
   };
   
   #define SCTP_FS_SPEC_LOG_SIZE 200
   struct sctp_fs_spec_log {
           uint32_t sent;
           uint32_t total_flight;
           uint32_t tsn;
           uint16_t book;
           uint8_t incr;
           uint8_t decr;
   };
   
   /* This struct is here to cut out the compatiabilty
    * pad that bulks up both the inp and stcb. The non
    * pad portion MUST stay in complete sync with
    * sctp_sndrcvinfo... i.e. if sinfo_xxxx is added
    * this must be done here too.
    */
   struct sctp_nonpad_sndrcvinfo {
           uint16_t sinfo_stream;
           uint16_t sinfo_ssn;
           uint16_t sinfo_flags;
           uint32_t sinfo_ppid;
           uint32_t sinfo_context;
           uint32_t sinfo_timetolive;
           uint32_t sinfo_tsn;
           uint32_t sinfo_cumtsn;
           sctp_assoc_t sinfo_assoc_id;
           uint16_t sinfo_keynumber;
           uint16_t sinfo_keynumber_valid;
   };
   
   /*
    * JRS - Structure to hold function pointers to the functions responsible
    * for congestion control.
    */
   
   struct sctp_cc_functions {
           void (*sctp_set_initial_cc_param) (struct sctp_tcb *stcb, struct sctp_nets *net);
           void (*sctp_cwnd_update_after_sack) (struct sctp_tcb *stcb,
                    struct sctp_association *asoc,
                    int accum_moved, int reneged_all, int will_exit);
           void (*sctp_cwnd_update_exit_pf) (struct sctp_tcb *stcb, struct sctp_nets *net);
           void (*sctp_cwnd_update_after_fr) (struct sctp_tcb *stcb,
                    struct sctp_association *asoc);
           void (*sctp_cwnd_update_after_timeout) (struct sctp_tcb *stcb,
                    struct sctp_nets *net);
           void (*sctp_cwnd_update_after_ecn_echo) (struct sctp_tcb *stcb,
                    struct sctp_nets *net, int in_window, int num_pkt_lost);
           void (*sctp_cwnd_update_after_packet_dropped) (struct sctp_tcb *stcb,
                    struct sctp_nets *net, struct sctp_pktdrop_chunk *cp,
                    uint32_t * bottle_bw, uint32_t * on_queue);
           void (*sctp_cwnd_update_after_output) (struct sctp_tcb *stcb,
                    struct sctp_nets *net, int burst_limit);
           void (*sctp_cwnd_update_packet_transmitted) (struct sctp_tcb *stcb,
                    struct sctp_nets *net);
           void (*sctp_cwnd_update_tsn_acknowledged) (struct sctp_nets *net,
                    struct sctp_tmit_chunk *);
           void (*sctp_cwnd_new_transmission_begins) (struct sctp_tcb *stcb,
                    struct sctp_nets *net);
           void (*sctp_cwnd_prepare_net_for_sack) (struct sctp_tcb *stcb,
                    struct sctp_nets *net);
           int (*sctp_cwnd_socket_option) (struct sctp_tcb *stcb, int set, struct sctp_cc_option *);
           void (*sctp_rtt_calculated) (struct sctp_tcb *, struct sctp_nets *, struct timeval *);
   };
   
   /*
    * RS - Structure to hold function pointers to the functions responsible
    * for stream scheduling.
    */
   struct sctp_ss_functions {
           void (*sctp_ss_init) (struct sctp_tcb *stcb, struct sctp_association *asoc,
                    int holds_lock);
           void (*sctp_ss_clear) (struct sctp_tcb *stcb, struct sctp_association *asoc,
                    int clear_values, int holds_lock);
           void (*sctp_ss_init_stream) (struct sctp_stream_out *strq, struct sctp_stream_out *with_strq);
           void (*sctp_ss_add_to_stream) (struct sctp_tcb *stcb, struct sctp_association *asoc,
                    struct sctp_stream_out *strq, struct sctp_stream_queue_pending *sp, int holds_lock);
           int (*sctp_ss_is_empty) (struct sctp_tcb *stcb, struct sctp_association *asoc);
           void (*sctp_ss_remove_from_stream) (struct sctp_tcb *stcb, struct sctp_association *asoc,
                    struct sctp_stream_out *strq, struct sctp_stream_queue_pending *sp, int holds_lock);
           struct sctp_stream_out *(*sctp_ss_select_stream) (struct sctp_tcb *stcb,
                               struct sctp_nets *net, struct sctp_association *asoc);
           void (*sctp_ss_scheduled) (struct sctp_tcb *stcb, struct sctp_nets *net,
                    struct sctp_association *asoc, struct sctp_stream_out *strq, int moved_how_much);
           void (*sctp_ss_packet_done) (struct sctp_tcb *stcb, struct sctp_nets *net,
                    struct sctp_association *asoc);
           int (*sctp_ss_get_value) (struct sctp_tcb *stcb, struct sctp_association *asoc,
                   struct sctp_stream_out *strq, uint16_t * value);
           int (*sctp_ss_set_value) (struct sctp_tcb *stcb, struct sctp_association *asoc,
                   struct sctp_stream_out *strq, uint16_t value);
   };
   
   /* used to save ASCONF chunks for retransmission */
   TAILQ_HEAD(sctp_asconf_head, sctp_asconf);
   struct sctp_asconf {
           TAILQ_ENTRY(sctp_asconf) next;
           uint32_t serial_number;
           uint16_t snd_count;
           struct mbuf *data;
           uint16_t len;
   };
   
   /* used to save ASCONF-ACK chunks for retransmission */
   TAILQ_HEAD(sctp_asconf_ackhead, sctp_asconf_ack);
   struct sctp_asconf_ack {
           TAILQ_ENTRY(sctp_asconf_ack) next;
           uint32_t serial_number;
           struct sctp_nets *last_sent_to;
           struct mbuf *data;
           uint16_t len;
   };
   
   /*
    * Here we have information about each individual association that we track.
    * We probably in production would be more dynamic. But for ease of
    * implementation we will have a fixed array that we hunt for in a linear
    * fashion.
    */
   struct sctp_association {
           /* association state */
           int state;
   
           /* queue of pending addrs to add/delete */
           struct sctp_asconf_addrhead asconf_queue;
   
           struct timeval time_entered;    /* time we entered state */
           struct timeval time_last_rcvd;
           struct timeval time_last_sent;
           struct timeval time_last_sat_advance;
           struct sctp_nonpad_sndrcvinfo def_send;
   
           /* timers and such */
           struct sctp_timer dack_timer;   /* Delayed ack timer */
           struct sctp_timer asconf_timer; /* asconf */
           struct sctp_timer strreset_timer;       /* stream reset */
           struct sctp_timer shut_guard_timer;     /* shutdown guard */
           struct sctp_timer autoclose_timer;      /* automatic close timer */
           struct sctp_timer delayed_event_timer;  /* timer for delayed events */
           struct sctp_timer delete_prim_timer;    /* deleting primary dst */
   
           /* list of restricted local addresses */
           struct sctpladdr sctp_restricted_addrs;
   
           /* last local address pending deletion (waiting for an address add) */
           struct sctp_ifa *asconf_addr_del_pending;
           /* Deleted primary destination (used to stop timer) */
           struct sctp_nets *deleted_primary;
   
           struct sctpnetlisthead nets;    /* remote address list */
   
           /* Free chunk list */
           struct sctpchunk_listhead free_chunks;
   
           /* Control chunk queue */
           struct sctpchunk_listhead control_send_queue;
   
           /* ASCONF chunk queue */
           struct sctpchunk_listhead asconf_send_queue;
   
           /*
            * Once a TSN hits the wire it is moved to the sent_queue. We
            * maintain two counts here (don't know if any but retran_cnt is
            * needed). The idea is that the sent_queue_retran_cnt reflects how
            * many chunks have been marked for retranmission by either T3-rxt
            * or FR.
            */
           struct sctpchunk_listhead sent_queue;
           struct sctpchunk_listhead send_queue;
   
           /* re-assembly queue for fragmented chunks on the inbound path */
           struct sctpchunk_listhead reasmqueue;
   
           /* Scheduling queues */
           union scheduling_data ss_data;
   
           /*
            * This pointer will be set to NULL most of the time. But when we
            * have a fragmented message, where we could not get out all of the
            * message at the last send then this will point to the stream to go
            * get data from.
            */
           struct sctp_stream_out *locked_on_sending;
   
           /* If an iterator is looking at me, this is it */
           struct sctp_iterator *stcb_starting_point_for_iterator;
   
           /* ASCONF save the last ASCONF-ACK so we can resend it if necessary */
           struct sctp_asconf_ackhead asconf_ack_sent;
   
           /*
            * pointer to last stream reset queued to control queue by us with
            * requests.
            */
           struct sctp_tmit_chunk *str_reset;
           /*
            * if Source Address Selection happening, this will rotate through
            * the link list.
            */
           struct sctp_laddr *last_used_address;
   
           /* stream arrays */
           struct sctp_stream_in *strmin;
           struct sctp_stream_out *strmout;
           uint8_t *mapping_array;
           /* primary destination to use */
           struct sctp_nets *primary_destination;
           struct sctp_nets *alternate;    /* If primary is down or PF */
           /* For CMT */
           struct sctp_nets *last_net_cmt_send_started;
           /* last place I got a data chunk from */
           struct sctp_nets *last_data_chunk_from;
           /* last place I got a control from */
           struct sctp_nets *last_control_chunk_from;
   
           /* circular looking for output selection */
           struct sctp_stream_out *last_out_stream;
   
           /*
            * wait to the point the cum-ack passes req->send_reset_at_tsn for
            * any req on the list.
            */
           struct sctp_resethead resetHead;
   
           /* queue of chunks waiting to be sent into the local stack */
           struct sctp_readhead pending_reply_queue;
   
           /* JRS - the congestion control functions are in this struct */
           struct sctp_cc_functions cc_functions;
           /*
            * JRS - value to store the currently loaded congestion control
            * module
            */
           uint32_t congestion_control_module;
           /* RS - the stream scheduling functions are in this struct */
           struct sctp_ss_functions ss_functions;
           /* RS - value to store the currently loaded stream scheduling module */
           uint32_t stream_scheduling_module;
   
           uint32_t vrf_id;
   
           uint32_t cookie_preserve_req;
           /* ASCONF next seq I am sending out, inits at init-tsn */
           uint32_t asconf_seq_out;
           uint32_t asconf_seq_out_acked;
           /* ASCONF last received ASCONF from peer, starts at peer's TSN-1 */
           uint32_t asconf_seq_in;
   
           /* next seq I am sending in str reset messages */
           uint32_t str_reset_seq_out;
           /* next seq I am expecting in str reset messages */
           uint32_t str_reset_seq_in;
   
           /* various verification tag information */
           uint32_t my_vtag;       /* The tag to be used. if assoc is re-initited
                                    * by remote end, and I have unlocked this
                                    * will be regenerated to a new random value. */
           uint32_t peer_vtag;     /* The peers last tag */
   
           uint32_t my_vtag_nonce;
           uint32_t peer_vtag_nonce;
   
           uint32_t assoc_id;
   
           /* This is the SCTP fragmentation threshold */
           uint32_t smallest_mtu;
   
           /*
            * Special hook for Fast retransmit, allows us to track the highest
            * TSN that is NEW in this SACK if gap ack blocks are present.
            */
           uint32_t this_sack_highest_gap;
   
           /*
            * The highest consecutive TSN that has been acked by peer on my
            * sends
            */
           uint32_t last_acked_seq;
   
           /* The next TSN that I will use in sending. */
           uint32_t sending_seq;
   
           /* Original seq number I used ??questionable to keep?? */
           uint32_t init_seq_number;
   
   
           /* The Advanced Peer Ack Point, as required by the PR-SCTP */
           /* (A1 in Section 4.2) */
           uint32_t advanced_peer_ack_point;
   
           /*
            * The highest consequetive TSN at the bottom of the mapping array
            * (for his sends).
            */
           uint32_t cumulative_tsn;
           /*
            * Used to track the mapping array and its offset bits. This MAY be
            * lower then cumulative_tsn.
            */
           uint32_t mapping_array_base_tsn;
           /*
            * used to track highest TSN we have received and is listed in the
            * mapping array.
            */
           uint32_t highest_tsn_inside_map;
   
           /* EY - new NR variables used for nr_sack based on mapping_array */
           uint8_t *nr_mapping_array;
           uint32_t highest_tsn_inside_nr_map;
   
           uint32_t fast_recovery_tsn;
           uint32_t sat_t3_recovery_tsn;
           uint32_t tsn_last_delivered;
           /*
            * For the pd-api we should re-write this a bit more efficent. We
            * could have multiple sctp_queued_to_read's that we are building at
            * once. Now we only do this when we get ready to deliver to the
            * socket buffer. Note that we depend on the fact that the struct is
            * "stuck" on the read queue until we finish all the pd-api.
            */
           struct sctp_queued_to_read *control_pdapi;
   
           uint32_t tsn_of_pdapi_last_delivered;
           uint32_t pdapi_ppid;
           uint32_t context;
           uint32_t last_reset_action[SCTP_MAX_RESET_PARAMS];
           uint32_t last_sending_seq[SCTP_MAX_RESET_PARAMS];
           uint32_t last_base_tsnsent[SCTP_MAX_RESET_PARAMS];
   #ifdef SCTP_ASOCLOG_OF_TSNS
           /*
            * special log  - This adds considerable size to the asoc, but
            * provides a log that you can use to detect problems via kgdb.
            */
           struct sctp_tsn_log in_tsnlog[SCTP_TSN_LOG_SIZE];
           struct sctp_tsn_log out_tsnlog[SCTP_TSN_LOG_SIZE];
           uint32_t cumack_log[SCTP_TSN_LOG_SIZE];
           uint32_t cumack_logsnt[SCTP_TSN_LOG_SIZE];
           uint16_t tsn_in_at;
           uint16_t tsn_out_at;
           uint16_t tsn_in_wrapped;
           uint16_t tsn_out_wrapped;
           uint16_t cumack_log_at;
           uint16_t cumack_log_atsnt;
   #endif                          /* SCTP_ASOCLOG_OF_TSNS */
   #ifdef SCTP_FS_SPEC_LOG
           struct sctp_fs_spec_log fslog[SCTP_FS_SPEC_LOG_SIZE];
           uint16_t fs_index;
   #endif
   
           /*
            * window state information and smallest MTU that I use to bound
            * segmentation
            */
           uint32_t peers_rwnd;
           uint32_t my_rwnd;
           uint32_t my_last_reported_rwnd;
           uint32_t sctp_frag_point;
   
           uint32_t total_output_queue_size;
   
           uint32_t sb_cc;         /* shadow of sb_cc */
           uint32_t sb_send_resv;  /* amount reserved on a send */
           uint32_t my_rwnd_control_len;   /* shadow of sb_mbcnt used for rwnd
                                            * control */
   #ifdef INET6
           uint32_t default_flowlabel;
   #endif
          uint32_t pr_sctp_cnt;
          int ctrl_queue_cnt;     /* could be removed  REM - NO IT CAN'T!! RRS */
          /*
           * All outbound datagrams queue into this list from the individual
           * stream queue. Here they get assigned a TSN and then await
           * sending. The stream seq comes when it is first put in the
           * individual str queue
           */
          unsigned int stream_queue_cnt;
          unsigned int send_queue_cnt;
          unsigned int sent_queue_cnt;
          unsigned int sent_queue_cnt_removeable;
          /*
           * Number on sent queue that are marked for retran until this value
           * is 0 we only send one packet of retran'ed data.
           */
          unsigned int sent_queue_retran_cnt;
  
          unsigned int size_on_reasm_queue;
          unsigned int cnt_on_reasm_queue;
          unsigned int fwd_tsn_cnt;
          /* amount of data (bytes) currently in flight (on all destinations) */
          unsigned int total_flight;
          /* Total book size in flight */
          unsigned int total_flight_count;        /* count of chunks used with
                                                   * book total */
          /* count of destinaton nets and list of destination nets */
          unsigned int numnets;
  
          /* Total error count on this association */
          unsigned int overall_error_count;
  
          unsigned int cnt_msg_on_sb;
  
          /* All stream count of chunks for delivery */
          unsigned int size_on_all_streams;
          unsigned int cnt_on_all_streams;
  
          /* Heart Beat delay in ms */
          uint32_t heart_beat_delay;
  
          /* autoclose */
          unsigned int sctp_autoclose_ticks;
  
          /* how many preopen streams we have */
          unsigned int pre_open_streams;
  
          /* How many streams I support coming into me */
          unsigned int max_inbound_streams;
  
          /* the cookie life I award for any cookie, in seconds */
          unsigned int cookie_life;
          /* time to delay acks for */
          unsigned int delayed_ack;
          unsigned int old_delayed_ack;
          unsigned int sack_freq;
          unsigned int data_pkts_seen;
  
          unsigned int numduptsns;
          int dup_tsns[SCTP_MAX_DUP_TSNS];
          unsigned int initial_init_rto_max;      /* initial RTO for INIT's */
          unsigned int initial_rto;       /* initial send RTO */
          unsigned int minrto;    /* per assoc RTO-MIN */
          unsigned int maxrto;    /* per assoc RTO-MAX */
  
          /* authentication fields */
          sctp_auth_chklist_t *local_auth_chunks;
          sctp_auth_chklist_t *peer_auth_chunks;
          sctp_hmaclist_t *local_hmacs;   /* local HMACs supported */
          sctp_hmaclist_t *peer_hmacs;    /* peer HMACs supported */
          struct sctp_keyhead shared_keys;        /* assoc's shared keys */
          sctp_authinfo_t authinfo;       /* randoms, cached keys */
          /*
           * refcnt to block freeing when a sender or receiver is off coping
           * user data in.
           */
          uint32_t refcnt;
          uint32_t chunks_on_out_queue;   /* total chunks floating around,
                                           * locked by send socket buffer */
          uint32_t peers_adaptation;
          uint16_t peer_hmac_id;  /* peer HMAC id to send */
  
          /*
           * Being that we have no bag to collect stale cookies, and that we
           * really would not want to anyway.. we will count them in this
           * counter. We of course feed them to the pigeons right away (I have
           * always thought of pigeons as flying rats).
           */
          uint16_t stale_cookie_count;
  
          /*
           * For the partial delivery API, if up, invoked this is what last
           * TSN I delivered
           */
          uint16_t str_of_pdapi;
          uint16_t ssn_of_pdapi;
  
          /* counts of actual built streams. Allocation may be more however */
          /* could re-arrange to optimize space here. */
          uint16_t streamincnt;
          uint16_t streamoutcnt;
          uint16_t strm_realoutsize;
          uint16_t strm_pending_add_size;
          /* my maximum number of retrans of INIT and SEND */
          /* copied from SCTP but should be individually setable */
          uint16_t max_init_times;
          uint16_t max_send_times;
  
          uint16_t def_net_failure;
  
          uint16_t def_net_pf_threshold;
  
          /*
           * lock flag: 0 is ok to send, 1+ (duals as a retran count) is
           * awaiting ACK
           */
          uint16_t mapping_array_size;
  
          uint16_t last_strm_seq_delivered;
          uint16_t last_strm_no_delivered;
  
          uint16_t last_revoke_count;
          int16_t num_send_timers_up;
  
          uint16_t stream_locked_on;
          uint16_t ecn_echo_cnt_onq;
  
          uint16_t free_chunk_cnt;
          uint8_t stream_locked;
          uint8_t authenticated;  /* packet authenticated ok */
          /*
           * This flag indicates that a SACK need to be sent. Initially this
           * is 1 to send the first sACK immediately.
           */
          uint8_t send_sack;
  
          /* max burst of new packets into the network */
          uint32_t max_burst;
          /* max burst of fast retransmit packets */
          uint32_t fr_max_burst;
  
          uint8_t sat_network;    /* RTT is in range of sat net or greater */
          uint8_t sat_network_lockout;    /* lockout code */
          uint8_t burst_limit_applied;    /* Burst limit in effect at last send? */
          /* flag goes on when we are doing a partial delivery api */
          uint8_t hb_random_values[4];
          uint8_t fragmented_delivery_inprogress;
          uint8_t fragment_flags;
          uint8_t last_flags_delivered;
          uint8_t hb_ect_randombit;
          uint8_t hb_random_idx;
          uint8_t default_dscp;
          uint8_t asconf_del_pending;     /* asconf delete last addr pending */
  
          /*
           * This value, plus all other ack'd but above cum-ack is added
           * together to cross check against the bit that we have yet to
           * define (probably in the SACK). When the cum-ack is updated, this
           * sum is updated as well.
           */
  
          /* Flags whether an extension is supported or not */
          uint8_t ecn_supported;
          uint8_t prsctp_supported;
          uint8_t auth_supported;
          uint8_t asconf_supported;
          uint8_t reconfig_supported;
          uint8_t nrsack_supported;
          uint8_t pktdrop_supported;
  
          /* Did the peer make the stream config (add out) request */
          uint8_t peer_req_out;
  
          uint8_t local_strreset_support;
  
          uint8_t peer_supports_nat;
  
          struct sctp_scoping scope;
          /* flags to handle send alternate net tracking */
          uint8_t used_alt_onsack;
          uint8_t used_alt_asconfack;
          uint8_t fast_retran_loss_recovery;
          uint8_t sat_t3_loss_recovery;
          uint8_t dropped_special_cnt;
          uint8_t seen_a_sack_this_pkt;
          uint8_t stream_reset_outstanding;
          uint8_t stream_reset_out_is_outstanding;
          uint8_t delayed_connection;
          uint8_t ifp_had_enobuf;
          uint8_t saw_sack_with_frags;
          uint8_t saw_sack_with_nr_frags;
          uint8_t in_asocid_hash;
          uint8_t assoc_up_sent;
          uint8_t adaptation_needed;
          uint8_t adaptation_sent;
          /* CMT variables */
          uint8_t cmt_dac_pkts_rcvd;
          uint8_t sctp_cmt_on_off;
          uint8_t iam_blocking;
          uint8_t cookie_how[8];
          /* JRS 5/21/07 - CMT PF variable */
          uint8_t sctp_cmt_pf;
          uint8_t use_precise_time;
          uint64_t sctp_features;
          uint16_t port;          /* remote UDP encapsulation port */
          /*
           * The mapping array is used to track out of order sequences above
           * last_acked_seq. 0 indicates packet missing 1 indicates packet
           * rec'd. We slide it up every time we raise last_acked_seq and 0
           * trailing locactions out.  If I get a TSN above the array
           * mappingArraySz, I discard the datagram and let retransmit happen.
           */
          uint32_t marked_retrans;
          uint32_t timoinit;
          uint32_t timodata;
          uint32_t timosack;
          uint32_t timoshutdown;
          uint32_t timoheartbeat;
          uint32_t timocookie;
          uint32_t timoshutdownack;
          struct timeval start_time;
          struct timeval discontinuity_time;
          uint64_t abandoned_unsent[SCTP_PR_SCTP_MAX + 1];
          uint64_t abandoned_sent[SCTP_PR_SCTP_MAX + 1];
  };
  
  #endif

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