mdoc.7/MANUAL STRUCTURE: add HARDWARE

[freebsd/src.git] / sys / netinet / sctp_structs.h

/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * 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.
 */

#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 seq;
        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(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

/* 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;
};

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_nonpad_sndrcvinfo sndrcv;
        ssize_t 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 {
        struct nhop_object *ro_nh;
        struct llentry *ro_lle;
        char *ro_prepend;
        uint16_t ro_plen;
        uint16_t ro_flags;
        uint16_t ro_mtu;
        uint16_t spare;
        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 */
        uint32_t 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;
        uint8_t flowtype;
};

struct sctp_data_chunkrec {
        uint32_t tsn;           /* the TSN of this transmit */
        uint32_t mid;           /* the message identifier of this transmit */
        uint16_t sid;           /* the stream number of this guy */
        uint32_t ppid;
        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 */
        uint32_t fsn;           /* Fragment Sequence Number */
        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;
};

struct sctp_queued_to_read {    /* sinfo structure Pluse more */
        uint16_t sinfo_stream;  /* 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 mid;           /* Fragment Index */
        uint32_t length;        /* length of data */
        uint32_t held_length;   /* length held in sb */
        uint32_t top_fsn;       /* Highest FSN in queue */
        uint32_t fsn_included;  /* Highest FSN in *data portion */
        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;
                 TAILQ_ENTRY(sctp_queued_to_read) next_instrm;
        struct sctpchunk_listhead reasm;
        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 pdapi_started;
        uint8_t some_taken;
        uint8_t last_frag_seen;
        uint8_t first_frag_seen;
        uint8_t on_read_q;
        uint8_t on_strm_q;
};

#define SCTP_ON_ORDERED 1
#define SCTP_ON_UNORDERED 2

/* 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.
 * ss_next and scheduled are only used by the FCFS stream scheduler.
 */
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 fsn;
        uint32_t length;
        uint32_t timetolive;
        uint32_t ppid;
        uint32_t context;
        uint16_t sinfo_flags;
        uint16_t sid;
        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;
        uint8_t processing;
        bool scheduled;
};

/*
 * 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;
        struct sctp_readhead uno_inqueue;
        uint32_t last_mid_delivered;    /* used for re-order */
        uint16_t sid;
        uint8_t delivery_started;
        uint8_t pd_api_started;
};

TAILQ_HEAD(sctpwheel_listhead, sctp_stream_out);
TAILQ_HEAD(sctplist_listhead, sctp_stream_queue_pending);

/*
 * This union holds all data necessary for
 * different stream schedulers.
 */
struct scheduling_data {
        struct sctp_stream_out *locked_on_sending;
        /* circular looking for output selection */
        struct sctp_stream_out *last_out_stream;
        union {
                struct sctpwheel_listhead wheel;
                struct sctplist_listhead list;
        }     out;
};

/* 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 parameters per stream
 * necessary for different stream schedulers.
 */
struct scheduling_parameters {
        union {
                struct ss_rr rr;
                struct ss_prio prio;
                struct ss_fb fb;
        }     ss;
        bool scheduled;
};

/* States for outgoing streams */
#define SCTP_STREAM_CLOSED           0x00
#define SCTP_STREAM_OPENING          0x01
#define SCTP_STREAM_OPEN             0x02
#define SCTP_STREAM_RESET_PENDING    0x03
#define SCTP_STREAM_RESET_IN_FLIGHT  0x04

/* This struct is used to track the traffic on outbound streams */
struct sctp_stream_out {
        struct sctp_streamhead outqueue;
        struct scheduling_parameters ss_params;
        uint32_t chunks_on_queues;      /* send queue and sent queue */
#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
        /*
         * For associations using DATA chunks, the lower 16-bit of
         * next_mid_ordered are used as the next SSN.
         */
        uint32_t next_mid_ordered;
        uint32_t next_mid_unordered;
        uint16_t sid;
        uint8_t last_msg_incomplete;
        uint8_t state;
};

#define SCTP_MAX_STREAMS_AT_ONCE_RESET 200

/* 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;
        uint32_t seq;
        uint16_t strm;
        uint16_t sz;
        uint16_t flgs;
        uint16_t in_pos;
        uint16_t in_out;
        uint16_t resv;
};

#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;
};

/*
 * 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);
        void (*sctp_ss_clear) (struct sctp_tcb *stcb, struct sctp_association *asoc,
            bool clear_values);
        void (*sctp_ss_init_stream) (struct sctp_tcb *stcb, 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);
        bool (*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);
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);
        bool (*sctp_ss_is_user_msgs_incomplete) (struct sctp_tcb *stcb, struct sctp_association *asoc);
};

/* 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 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;

        /* Scheduling queues */
        struct scheduling_data ss_data;

        /* 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;

        /*
         * 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;
        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 */
        uint32_t 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 */
        uint32_t 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];
        uint32_t initial_init_rto_max;  /* initial RTO for INIT's */
        uint32_t initial_rto;   /* initial send RTO */
        uint32_t minrto;        /* per assoc RTO-MIN */
        uint32_t 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;
        uint32_t default_mtu;
        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 */
        uint8_t trigger_reset;
        /*
         * 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;
        uint8_t idata_supported;

        /* Zero checksum supported information */
        uint8_t rcv_edmid;
        uint8_t snd_edmid;

        /* 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_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;
        uint32_t max_cwnd;
        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