text: /*-
   * Copyright (c) 2001-2007, 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.
   */
  
  #ifdef __FreeBSD__
  #include <sys/cdefs.h>
  __FBSDID("$FreeBSD: head/sys/netinet/sctp_pcb.h 279859 2015-03-10 19:49:25Z tuexen $");
  #endif
  
  #ifndef _NETINET_SCTP_PCB_H_
  #define _NETINET_SCTP_PCB_H_
  
  #include <netinet/sctp_os.h>
  #include <netinet/sctp.h>
  #include <netinet/sctp_constants.h>
  #include <netinet/sctp_sysctl.h>
  
  LIST_HEAD(sctppcbhead, sctp_inpcb);
  LIST_HEAD(sctpasochead, sctp_tcb);
  LIST_HEAD(sctpladdr, sctp_laddr);
  LIST_HEAD(sctpvtaghead, sctp_tagblock);
  LIST_HEAD(sctp_vrflist, sctp_vrf);
  LIST_HEAD(sctp_ifnlist, sctp_ifn);
  LIST_HEAD(sctp_ifalist, sctp_ifa);
  TAILQ_HEAD(sctp_readhead, sctp_queued_to_read);
  TAILQ_HEAD(sctp_streamhead, sctp_stream_queue_pending);
  
  #include <netinet/sctp_structs.h>
  #include <netinet/sctp_auth.h>
  
  #define SCTP_PCBHASH_ALLADDR(port, mask) (port & mask)
  #define SCTP_PCBHASH_ASOC(tag, mask) (tag & mask)
  
  struct sctp_vrf {
  	LIST_ENTRY (sctp_vrf) next_vrf;
  	struct sctp_ifalist *vrf_addr_hash;
  	struct sctp_ifnlist ifnlist;
  	uint32_t vrf_id;
  	uint32_t tbl_id_v4;		/* default v4 table id */
  	uint32_t tbl_id_v6;		/* default v6 table id */
  	uint32_t total_ifa_count;
  	u_long   vrf_addr_hashmark;
  	uint32_t refcount;
  };
  
  struct sctp_ifn {
  	struct sctp_ifalist ifalist;
  	struct sctp_vrf *vrf;
  	LIST_ENTRY(sctp_ifn) next_ifn;
  	LIST_ENTRY(sctp_ifn) next_bucket;
  	void     *ifn_p;	/* never access without appropriate lock */
  	uint32_t ifn_mtu;
  	uint32_t ifn_type;
  	uint32_t ifn_index;	/* shorthand way to look at ifn for reference */
  	uint32_t refcount;	/* number of reference held should be >= ifa_count */
  	uint32_t ifa_count;	/* IFA's we hold (in our list - ifalist)*/
  	uint32_t num_v6;	/* number of v6 addresses */
  	uint32_t num_v4;	/* number of v4 addresses */
  	uint32_t registered_af;	/* registered address family for i/f events */
  	char     ifn_name[SCTP_IFNAMSIZ];
  };
  
  /* SCTP local IFA flags */
  #define SCTP_ADDR_VALID         0x00000001	/* its up and active */
  #define SCTP_BEING_DELETED      0x00000002	/* being deleted,
  						 * when refcount = 0. Note
  						 * that it is pulled from the ifn list
  						 * and ifa_p is nulled right away but
  						 * it cannot be freed until the last *net
  						 * pointing to it is deleted.
  						 */
  #define SCTP_ADDR_DEFER_USE     0x00000004	/* Hold off using this one */
  #define SCTP_ADDR_IFA_UNUSEABLE 0x00000008
  
  struct sctp_ifa {
  	LIST_ENTRY(sctp_ifa) next_ifa;
  	LIST_ENTRY(sctp_ifa) next_bucket;
  	struct sctp_ifn *ifn_p;	/* back pointer to parent ifn */
  	void    *ifa;		/* pointer to ifa, needed for flag
  				 * update for that we MUST lock
  				 * appropriate locks. This is for V6.
  				 */
  	union sctp_sockstore address;
  	uint32_t refcount;	/* number of folks refering to this */
  	uint32_t flags;
  	uint32_t localifa_flags;
  	uint32_t vrf_id;	/* vrf_id of this addr (for deleting) */
  	uint8_t src_is_loop;
  	uint8_t src_is_priv;
  	uint8_t src_is_glob;
  	uint8_t resv;
  };
  
  struct sctp_laddr {
  	LIST_ENTRY(sctp_laddr) sctp_nxt_addr;	/* next in list */
  	struct sctp_ifa *ifa;
  	uint32_t action;		/* Used during asconf and adding
  					 * if no-zero src-addr selection will
  					 * not consider this address.
  					 */
  	struct timeval start_time;      /* time when this address was created */
  };
  
  struct sctp_block_entry {
  	int error;
  };
  
  struct sctp_timewait {
  	uint32_t tv_sec_at_expire;	/* the seconds from boot to expire */
          uint32_t v_tag;		        /* the vtag that can not be reused */
          uint16_t lport;                 /* the local port used in vtag */
          uint16_t rport;                 /* the remote port used in vtag */
  };
  
  struct sctp_tagblock {
  	LIST_ENTRY(sctp_tagblock) sctp_nxt_tagblock;
  	struct sctp_timewait vtag_block[SCTP_NUMBER_IN_VTAG_BLOCK];
  };
  
  
  struct sctp_epinfo {
  #if defined(__FreeBSD__)
  #ifdef INET
  	struct socket *udp4_tun_socket;
  #endif
  #ifdef INET6
  	struct socket *udp6_tun_socket;
  #endif
  #endif
  	struct sctpasochead *sctp_asochash;
  	u_long hashasocmark;
  
  	struct sctppcbhead *sctp_ephash;
  	u_long hashmark;
  
  	/*-
  	 * The TCP model represents a substantial overhead in that we get an
  	 * additional hash table to keep explicit connections in. The
  	 * listening TCP endpoint will exist in the usual ephash above and
  	 * accept only INIT's. It will be incapable of sending off an INIT.
  	 * When a dg arrives we must look in the normal ephash. If we find a
  	 * TCP endpoint that will tell us to go to the specific endpoint
  	 * hash and re-hash to find the right assoc/socket. If we find a UDP
  	 * model socket we then must complete the lookup. If this fails,
  	 * i.e. no association can be found then we must continue to see if
  	 * a sctp_peeloff()'d socket is in the tcpephash (a spun off socket
  	 * acts like a TCP model connected socket).
  	 */
  	struct sctppcbhead *sctp_tcpephash;
  	u_long hashtcpmark;
  	uint32_t hashtblsize;
  
  	struct sctp_vrflist *sctp_vrfhash;
  	u_long hashvrfmark;
  
  	struct sctp_ifnlist *vrf_ifn_hash;
  	u_long   vrf_ifn_hashmark;
  
  	struct sctppcbhead listhead;
  	struct sctpladdr addr_wq;
  
  #if defined(__APPLE__)
  	struct inpcbhead inplisthead;
  	struct inpcbinfo sctbinfo;
  #endif
  	/* ep zone info */
  	sctp_zone_t ipi_zone_ep;
  	sctp_zone_t ipi_zone_asoc;
  	sctp_zone_t ipi_zone_laddr;
  	sctp_zone_t ipi_zone_net;
  	sctp_zone_t ipi_zone_chunk;
  	sctp_zone_t ipi_zone_readq;
  	sctp_zone_t ipi_zone_strmoq;
  	sctp_zone_t ipi_zone_asconf;
  	sctp_zone_t ipi_zone_asconf_ack;
  
  #if defined(__FreeBSD__) && __FreeBSD_version >= 503000
  #if __FreeBSD_version <= 602000
  	struct mtx ipi_ep_mtx;
  #else
  	struct rwlock ipi_ep_mtx;
  #endif
  	struct mtx ipi_iterator_wq_mtx;
  #if __FreeBSD_version <= 602000
  	struct mtx ipi_addr_mtx;
  #else
  	struct rwlock ipi_addr_mtx;
  #endif
  	struct mtx ipi_pktlog_mtx;
  	struct mtx wq_addr_mtx;
  #elif defined(SCTP_PROCESS_LEVEL_LOCKS)
  	userland_mutex_t ipi_ep_mtx;
  	userland_mutex_t ipi_addr_mtx;
  	userland_mutex_t ipi_count_mtx;
  	userland_mutex_t ipi_pktlog_mtx;
  	userland_mutex_t wq_addr_mtx;
  #elif defined(__APPLE__)
  #ifdef _KERN_LOCKS_H_
  	lck_mtx_t *ipi_addr_mtx;
  	lck_mtx_t *ipi_count_mtx;
  	lck_mtx_t *ipi_pktlog_mtx;
  	lck_mtx_t *logging_mtx;
  	lck_mtx_t *wq_addr_mtx;
  #else
  	void *ipi_count_mtx;
  	void *logging_mtx;
  #endif /* _KERN_LOCKS_H_ */
  #elif defined(__Windows__)
  	struct rwlock ipi_ep_lock;
  	struct rwlock ipi_addr_lock;
  	struct spinlock ipi_pktlog_mtx;
  	struct rwlock wq_addr_mtx;
  #elif defined(__Userspace__)
      /* TODO decide on __Userspace__ locks */
  #endif
  	uint32_t ipi_count_ep;
  
  	/* assoc/tcb zone info */
  	uint32_t ipi_count_asoc;
  
  	/* local addrlist zone info */
  	uint32_t ipi_count_laddr;
  
  	/* remote addrlist zone info */
  	uint32_t ipi_count_raddr;
  
  	/* chunk structure list for output */
  	uint32_t ipi_count_chunk;
  
  	/* socket queue zone info */
  	uint32_t ipi_count_readq;
  
  	/* socket queue zone info */
  	uint32_t ipi_count_strmoq;
  
  	/* Number of vrfs */
  	uint32_t ipi_count_vrfs;
  
          /* Number of ifns */
  	uint32_t ipi_count_ifns;
  
          /* Number of ifas */
  	uint32_t ipi_count_ifas;
  
  	/* system wide number of free chunks hanging around */
  	uint32_t ipi_free_chunks;
  	uint32_t ipi_free_strmoq;
  
  	struct sctpvtaghead vtag_timewait[SCTP_STACK_VTAG_HASH_SIZE];
  
  	/* address work queue handling */
  	struct sctp_timer addr_wq_timer;
  
  #if defined(_SCTP_NEEDS_CALLOUT_) || defined(_USER_SCTP_NEEDS_CALLOUT_)
  	struct calloutlist callqueue;
  #endif
  };
  
  
  struct sctp_base_info {
  	/* All static structures that
  	 * anchor the system must be here.
  	 */
  	struct sctp_epinfo sctppcbinfo;
  #if defined(__FreeBSD__) && defined(SMP) && defined(SCTP_USE_PERCPU_STAT)
  	struct sctpstat    *sctpstat;
  #else
  	struct sctpstat    sctpstat;
  #endif
  	struct sctp_sysctl sctpsysctl;
  	uint8_t first_time;
  	char sctp_pcb_initialized;
  #if defined(SCTP_PACKET_LOGGING)
  	int packet_log_writers;
  	int packet_log_end;
  	uint8_t packet_log_buffer[SCTP_PACKET_LOG_SIZE];
  #endif
  #if defined(__APPLE__)
  	int sctp_main_timer_ticks;
  #endif
  #if defined(__Userspace__)
  	userland_mutex_t timer_mtx;
  	userland_thread_t timer_thread;
  	uint8_t timer_thread_should_exit;
  #if !defined(__Userspace_os_Windows)
  #if defined(INET) || defined(INET6)
  	int userspace_route;
  	userland_thread_t recvthreadroute;
  #endif
  #endif
  #ifdef INET
  	int userspace_rawsctp;
  	int userspace_udpsctp;
  	userland_thread_t recvthreadraw;
  	userland_thread_t recvthreadudp;
  #endif
  #ifdef INET6
  	int userspace_rawsctp6;
  	int userspace_udpsctp6;
  	userland_thread_t recvthreadraw6;
  	userland_thread_t recvthreadudp6;
  #endif
  	int (*conn_output)(void *addr, void *buffer, size_t length, uint8_t tos, uint8_t set_df);
  	void (*debug_printf)(const char *format, ...);
  #endif
  };
  
  /*-
   * Here we have all the relevant information for each SCTP entity created. We
   * will need to modify this as approprate. We also need to figure out how to
   * access /dev/random.
   */
  struct sctp_pcb {
  	unsigned int time_of_secret_change;	/* number of seconds from
  						 * timeval.tv_sec */
  	uint32_t secret_key[SCTP_HOW_MANY_SECRETS][SCTP_NUMBER_OF_SECRETS];
  	unsigned int size_of_a_cookie;
  
  	unsigned int sctp_timeoutticks[SCTP_NUM_TMRS];
  	unsigned int sctp_minrto;
  	unsigned int sctp_maxrto;
  	unsigned int initial_rto;
  	int initial_init_rto_max;
  
  	unsigned int sctp_sack_freq;
  	uint32_t sctp_sws_sender;
  	uint32_t sctp_sws_receiver;
  
  	uint32_t sctp_default_cc_module;
  	uint32_t sctp_default_ss_module;
  	/* authentication related fields */
  	struct sctp_keyhead shared_keys;
  	sctp_auth_chklist_t *local_auth_chunks;
  	sctp_hmaclist_t *local_hmacs;
  	uint16_t default_keyid;
  
  	/* various thresholds */
  	/* Max times I will init at a guy */
  	uint16_t max_init_times;
  
  	/* Max times I will send before we consider someone dead */
  	uint16_t max_send_times;
  
  	uint16_t def_net_failure;
  
  	uint16_t def_net_pf_threshold;
  
  	/* number of streams to pre-open on a association */
  	uint16_t pre_open_stream_count;
  	uint16_t max_open_streams_intome;
  
  	/* random number generator */
  	uint32_t random_counter;
  	uint8_t random_numbers[SCTP_SIGNATURE_ALOC_SIZE];
  	uint8_t random_store[SCTP_SIGNATURE_ALOC_SIZE];
  
  	/*
  	 * This timer is kept running per endpoint.  When it fires it will
  	 * change the secret key.  The default is once a hour
  	 */
  	struct sctp_timer signature_change;
  
  	/* Zero copy full buffer timer */
  	struct sctp_timer zero_copy_timer;
          /* Zero copy app to transport (sendq) read repulse timer */
  	struct sctp_timer zero_copy_sendq_timer;
  	uint32_t def_cookie_life;
  	/* defaults to 0 */
  	int auto_close_time;
  	uint32_t initial_sequence_debug;
  	uint32_t adaptation_layer_indicator;
  	uint8_t adaptation_layer_indicator_provided;
  	uint32_t store_at;
  	uint32_t max_burst;
  	uint32_t fr_max_burst;
  #ifdef INET6
  	uint32_t default_flowlabel;
  #endif
  	uint8_t default_dscp;
  	char current_secret_number;
  	char last_secret_number;
  	uint16_t port; /* remote UDP encapsulation port */
  };
  
  #ifndef SCTP_ALIGNMENT
  #define SCTP_ALIGNMENT 32
  #endif
  
  #ifndef SCTP_ALIGNM1
  #define SCTP_ALIGNM1 (SCTP_ALIGNMENT-1)
  #endif
  
  #define sctp_lport ip_inp.inp.inp_lport
  
  struct sctp_pcbtsn_rlog {
  	uint32_t vtag;
  	uint16_t strm;
  	uint16_t seq;
  	uint16_t sz;
  	uint16_t flgs;
  };
  #define SCTP_READ_LOG_SIZE 135	/* we choose the number to make a pcb a page */
  
  
  struct sctp_inpcb {
  	/*-
  	 * put an inpcb in front of it all, kind of a waste but we need to
  	 * for compatability with all the other stuff.
  	 */
  	union {
  		struct inpcb inp;
  		char align[(sizeof(struct in6pcb) + SCTP_ALIGNM1) &
  		        ~SCTP_ALIGNM1];
  	}     ip_inp;
  
  #if defined(__APPLE__)
  	/* leave some space in case i386 inpcb is bigger than ppc */
  	uint8_t		padding[128];
  #endif
  
  	/* Socket buffer lock protects read_queue and of course sb_cc */
  	struct sctp_readhead read_queue;
  
  	LIST_ENTRY(sctp_inpcb) sctp_list;	/* lists all endpoints */
          /* hash of all endpoints for model */
  	LIST_ENTRY(sctp_inpcb) sctp_hash;
  	/* count of local addresses bound, 0 if bound all */
  	int laddr_count;
  
  	/* list of addrs in use by the EP, NULL if bound-all */
  	struct sctpladdr sctp_addr_list;
  	/* used for source address selection rotation when we are subset bound */
  	struct sctp_laddr *next_addr_touse;
  
  	/* back pointer to our socket */
  	struct socket *sctp_socket;
  	uint64_t sctp_features;	/* Feature flags */
  	uint32_t sctp_flags;	/* INP state flag set */
  	uint32_t sctp_mobility_features; /* Mobility  Feature flags */
  	struct sctp_pcb sctp_ep;/* SCTP ep data */
  	/* head of the hash of all associations */
  	struct sctpasochead *sctp_tcbhash;
  	u_long sctp_hashmark;
  	/* head of the list of all associations */
  	struct sctpasochead sctp_asoc_list;
  #ifdef SCTP_TRACK_FREED_ASOCS
  	struct sctpasochead sctp_asoc_free_list;
  #endif
  	struct sctp_iterator *inp_starting_point_for_iterator;
  	uint32_t sctp_frag_point;
  	uint32_t partial_delivery_point;
  	uint32_t sctp_context;
  	uint32_t max_cwnd;
  	uint8_t local_strreset_support;
  	uint32_t sctp_cmt_on_off;
  	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;
  	struct sctp_nonpad_sndrcvinfo def_send;
  	/*-
  	 * These three are here for the sosend_dgram
  	 * (pkt, pkt_last and control).
  	 * routine. However, I don't think anyone in
  	 * the current FreeBSD kernel calls this. So
  	 * they are candidates with sctp_sendm for
  	 * de-supporting.
  	 */
  #ifdef __Panda__
  	pakhandle_type pak_to_read;
  	pakhandle_type pak_to_read_sendq;
  #endif
  	struct mbuf *pkt, *pkt_last;
  	struct mbuf *control;
  #if !(defined(__FreeBSD__) || defined(__APPLE__) || defined(__Windows__) || defined(__Userspace__))
  #ifndef INP_IPV6
  #define INP_IPV6	0x1
  #endif
  #ifndef INP_IPV4
  #define INP_IPV4	0x2
  #endif
  	uint8_t inp_vflag;
                                 /* TODO __Userspace__ where is our inp_vlag going to be? */
  	uint8_t inp_ip_ttl;
          uint8_t inp_ip_tos;    /* defined as macro in user_inpcb.h */
  	uint8_t inp_ip_resv;
  #endif
  #if defined(__FreeBSD__) && __FreeBSD_version >= 503000
  	struct mtx inp_mtx;
  	struct mtx inp_create_mtx;
  	struct mtx inp_rdata_mtx;
  	int32_t refcount;
  #elif defined(SCTP_PROCESS_LEVEL_LOCKS)
  	userland_mutex_t inp_mtx;
  	userland_mutex_t inp_create_mtx;
  	userland_mutex_t inp_rdata_mtx;
  	int32_t refcount;
  #elif defined(__APPLE__)
  #if defined(SCTP_APPLE_RWLOCK)
  	lck_rw_t *inp_mtx;
  #else
  	lck_mtx_t *inp_mtx;
  #endif
  	lck_mtx_t *inp_create_mtx;
  	lck_mtx_t *inp_rdata_mtx;
  #elif defined(__Windows__)
  	struct rwlock inp_lock;
  	struct spinlock inp_create_lock;
  	struct spinlock inp_rdata_lock;
  	int32_t refcount;
  #elif defined(__Userspace__)
      /* TODO decide on __Userspace__ locks */
  	int32_t refcount;
  #endif
  #if defined(__APPLE__)
  	int32_t refcount;
  
  	uint32_t lock_caller1;
  	uint32_t lock_caller2;
  	uint32_t lock_caller3;
  	uint32_t unlock_caller1;
  	uint32_t unlock_caller2;
  	uint32_t unlock_caller3;
  	uint32_t getlock_caller1;
  	uint32_t getlock_caller2;
  	uint32_t getlock_caller3;
  	uint32_t gen_count;
  	uint32_t lock_gen_count;
  	uint32_t unlock_gen_count;
  	uint32_t getlock_gen_count;
  
  	uint32_t i_am_here_file;
  	uint32_t i_am_here_line;
  #endif
  	uint32_t def_vrf_id;
  #ifdef SCTP_MVRF
  	uint32_t *m_vrf_ids;
  	uint32_t num_vrfs;
  	uint32_t vrf_size;
  #endif
  	uint32_t total_sends;
  	uint32_t total_recvs;
  	uint32_t last_abort_code;
  	uint32_t total_nospaces;
  	struct sctpasochead *sctp_asocidhash;
  	u_long hashasocidmark;
          uint32_t sctp_associd_counter;
  
  #ifdef SCTP_ASOCLOG_OF_TSNS
  	struct sctp_pcbtsn_rlog readlog[SCTP_READ_LOG_SIZE];
  	uint32_t readlog_index;
  #endif
  #if defined(__Userspace__)
  	void *ulp_info;
  	int (*recv_callback)(struct socket *, union sctp_sockstore, void *, size_t,
                               struct sctp_rcvinfo, int, void *);
  	uint32_t send_sb_threshold;
  	int (*send_callback)(struct socket *, uint32_t);
  #endif
  };
  
  #if defined(__Userspace__)
  int register_recv_cb (struct socket *,
                        int (*)(struct socket *, union sctp_sockstore, void *, size_t,
                                struct sctp_rcvinfo, int, void *));
  int register_send_cb (struct socket *, uint32_t, int (*)(struct socket *, uint32_t));
  int register_ulp_info (struct socket *, void *);
  
  #endif
  struct sctp_tcb {
  	struct socket *sctp_socket;	/* back pointer to socket */
  	struct sctp_inpcb *sctp_ep;	/* back pointer to ep */
  	LIST_ENTRY(sctp_tcb) sctp_tcbhash;	/* next link in hash
  						 * table */
          LIST_ENTRY(sctp_tcb) sctp_tcblist;	/* list of all of the
  						 * TCB's */
          LIST_ENTRY(sctp_tcb) sctp_tcbasocidhash;	/* next link in asocid
  							 * hash table
  							 */
          LIST_ENTRY(sctp_tcb) sctp_asocs;	/* vtag hash list */
  	struct sctp_block_entry *block_entry;	/* pointer locked by  socket
  						 * send buffer */
  	struct sctp_association asoc;
  	/*-
  	 * freed_by_sorcv_sincelast is protected by the sockbuf_lock NOT the
  	 * tcb_lock. Its special in this way to help avoid extra mutex calls
  	 * in the reading of data.
  	 */
  	uint32_t freed_by_sorcv_sincelast;
  	uint32_t total_sends;
  	uint32_t total_recvs;
  	int freed_from_where;
  	uint16_t rport;		/* remote port in network format */
  	uint16_t resv;
  #if defined(__FreeBSD__) && __FreeBSD_version >= 503000
  	struct mtx tcb_mtx;
  	struct mtx tcb_send_mtx;
  #elif defined(SCTP_PROCESS_LEVEL_LOCKS)
  	userland_mutex_t tcb_mtx;
  	userland_mutex_t tcb_send_mtx;
  #elif defined(__APPLE__)
  	lck_mtx_t* tcb_mtx;
  	lck_mtx_t* tcb_send_mtx;
  #elif defined(__Windows__)
  	struct spinlock tcb_lock;
  	struct spinlock tcb_send_lock;
  #elif defined(__Userspace__)
      /* TODO decide on __Userspace__ locks */
  #endif
  #if defined(__APPLE__)
  	uint32_t caller1;
  	uint32_t caller2;
  	uint32_t caller3;
  #endif
  };
  
  
  #if defined(__FreeBSD__) && __FreeBSD_version >= 503000
  
  #include <netinet/sctp_lock_bsd.h>
  
  #elif defined(__APPLE__)
  /*
   * Apple MacOS X 10.4 "Tiger"
   */
  
  #include <netinet/sctp_lock_apple_fg.h>
  
  #elif defined(SCTP_PROCESS_LEVEL_LOCKS)
  
  #include <netinet/sctp_process_lock.h>
  
  #elif defined(__Windows__)
  
  #include <netinet/sctp_lock_windows.h>
  
  #elif defined(__Userspace__)
  
  #include <netinet/sctp_lock_userspace.h>
  
  #else
  /*
   * Pre-5.x FreeBSD, and others.
   */
  #include <netinet/sctp_lock_empty.h>
  #endif
  
  /* TODO where to put non-_KERNEL things for __Userspace__? */
  #if defined(_KERNEL) || defined(__Userspace__)
  
  /* Attention Julian, this is the extern that
   * goes with the base info. sctp_pcb.c has
   * the real definition.
   */
  #if defined(__FreeBSD__) && __FreeBSD_version >= 801000
  VNET_DECLARE(struct sctp_base_info, system_base_info) ;
  #else
  extern struct sctp_base_info system_base_info;
  #endif
  
  #ifdef INET6
  int SCTP6_ARE_ADDR_EQUAL(struct sockaddr_in6 *a, struct sockaddr_in6 *b);
  #endif
  
  void sctp_fill_pcbinfo(struct sctp_pcbinfo *);
  
  struct sctp_ifn *
  sctp_find_ifn(void *ifn, uint32_t ifn_index);
  
  struct sctp_vrf *sctp_allocate_vrf(int vrfid);
  struct sctp_vrf *sctp_find_vrf(uint32_t vrfid);
  void sctp_free_vrf(struct sctp_vrf *vrf);
  
  /*-
   * Change address state, can be used if
   * O/S supports telling transports about
   * changes to IFA/IFN's (link layer triggers).
   * If a ifn goes down, we will do src-addr-selection
   * and NOT use that, as a source address. This does
   * not stop the routing system from routing out
   * that interface, but we won't put it as a source.
   */
  void sctp_mark_ifa_addr_down(uint32_t vrf_id, struct sockaddr *addr, const char *if_name, uint32_t ifn_index);
  void sctp_mark_ifa_addr_up(uint32_t vrf_id, struct sockaddr *addr, const char *if_name, uint32_t ifn_index);
  
  struct sctp_ifa *
  sctp_add_addr_to_vrf(uint32_t vrfid,
  		     void *ifn, uint32_t ifn_index, uint32_t ifn_type,
  		     const char *if_name,
  		     void *ifa, struct sockaddr *addr, uint32_t ifa_flags,
  		     int dynamic_add);
  
  void sctp_update_ifn_mtu(uint32_t ifn_index, uint32_t mtu);
  
  void sctp_free_ifn(struct sctp_ifn *sctp_ifnp);
  void sctp_free_ifa(struct sctp_ifa *sctp_ifap);
  
  
  void sctp_del_addr_from_vrf(uint32_t vrfid, struct sockaddr *addr,
  			    uint32_t ifn_index, const char *if_name);
  
  
  
  struct sctp_nets *sctp_findnet(struct sctp_tcb *, struct sockaddr *);
  
  struct sctp_inpcb *sctp_pcb_findep(struct sockaddr *, int, int, uint32_t);
  
  #if defined(__FreeBSD__) && __FreeBSD_version >= 500000
  int sctp_inpcb_bind(struct socket *, struct sockaddr *,
  		    struct sctp_ifa *,struct thread *);
  #elif defined(__Windows__)
  int sctp_inpcb_bind(struct socket *, struct sockaddr *,
  		    struct sctp_ifa *,PKTHREAD);
  #else
  /* struct proc is a dummy for __Userspace__ */
  int sctp_inpcb_bind(struct socket *, struct sockaddr *,
  		    struct sctp_ifa *, struct proc *);
  #endif
  
  struct sctp_tcb *
  sctp_findassociation_addr(struct mbuf *, int,
      struct sockaddr *, struct sockaddr *,
      struct sctphdr *, struct sctp_chunkhdr *, struct sctp_inpcb **,
      struct sctp_nets **, uint32_t vrf_id);
  
  struct sctp_tcb *
  sctp_findassociation_addr_sa(struct sockaddr *,
      struct sockaddr *, struct sctp_inpcb **, struct sctp_nets **, int, uint32_t);
  
  void
  sctp_move_pcb_and_assoc(struct sctp_inpcb *, struct sctp_inpcb *,
      struct sctp_tcb *);
  
  /*-
   * For this call ep_addr, the to is the destination endpoint address of the
   * peer (relative to outbound). The from field is only used if the TCP model
   * is enabled and helps distingush amongst the subset bound (non-boundall).
   * The TCP model MAY change the actual ep field, this is why it is passed.
   */
  struct sctp_tcb *
  sctp_findassociation_ep_addr(struct sctp_inpcb **,
      struct sockaddr *, struct sctp_nets **, struct sockaddr *,
      struct sctp_tcb *);
  
  struct sctp_tcb *
  sctp_findasoc_ep_asocid_locked(struct sctp_inpcb *inp, sctp_assoc_t asoc_id, int want_lock);
  
  struct sctp_tcb *
  sctp_findassociation_ep_asocid(struct sctp_inpcb *,
      sctp_assoc_t, int);
  
  struct sctp_tcb *
  sctp_findassociation_ep_asconf(struct mbuf *, int, struct sockaddr *,
  			       struct sctphdr *, struct sctp_inpcb **, struct sctp_nets **, uint32_t vrf_id);
  
  int sctp_inpcb_alloc(struct socket *so, uint32_t vrf_id);
  
  int sctp_is_address_on_local_host(struct sockaddr *addr, uint32_t vrf_id);
  
  void sctp_inpcb_free(struct sctp_inpcb *, int, int);
  
  #if defined(__FreeBSD__) && __FreeBSD_version >= 500000
  struct sctp_tcb *
  sctp_aloc_assoc(struct sctp_inpcb *, struct sockaddr *,
                  int *, uint32_t, uint32_t, struct thread *);
  #elif defined(__Windows__)
  struct sctp_tcb *
  sctp_aloc_assoc(struct sctp_inpcb *, struct sockaddr *,
                  int *, uint32_t, uint32_t, PKTHREAD);
  #else
  /* proc will be NULL for __Userspace__ */
  struct sctp_tcb *
  sctp_aloc_assoc(struct sctp_inpcb *, struct sockaddr *,
                  int *, uint32_t, uint32_t, struct proc *);
  #endif
  
  int sctp_free_assoc(struct sctp_inpcb *, struct sctp_tcb *, int, int);
  
  
  void sctp_delete_from_timewait(uint32_t, uint16_t, uint16_t);
  
  int sctp_is_in_timewait(uint32_t tag, uint16_t lport, uint16_t rport);
  
  void
  sctp_add_vtag_to_timewait(uint32_t tag, uint32_t time, uint16_t lport, uint16_t rport);
  
  void sctp_add_local_addr_ep(struct sctp_inpcb *, struct sctp_ifa *, uint32_t);
  
  int sctp_insert_laddr(struct sctpladdr *, struct sctp_ifa *, uint32_t);
  
  void sctp_remove_laddr(struct sctp_laddr *);
  
  void sctp_del_local_addr_ep(struct sctp_inpcb *, struct sctp_ifa *);
  
  int sctp_add_remote_addr(struct sctp_tcb *, struct sockaddr *, struct sctp_nets **, int, int);
  
  void sctp_remove_net(struct sctp_tcb *, struct sctp_nets *);
  
  int sctp_del_remote_addr(struct sctp_tcb *, struct sockaddr *);
  
  void sctp_pcb_init(void);
  
  void sctp_pcb_finish(void);
  
  void sctp_add_local_addr_restricted(struct sctp_tcb *, struct sctp_ifa *);
  void sctp_del_local_addr_restricted(struct sctp_tcb *, struct sctp_ifa *);
  
  int
  sctp_load_addresses_from_init(struct sctp_tcb *, struct mbuf *, int, int,
      struct sockaddr *, struct sockaddr *, struct sockaddr *);
  
  int
  sctp_set_primary_addr(struct sctp_tcb *, struct sockaddr *,
      struct sctp_nets *);
  
  int sctp_is_vtag_good(uint32_t, uint16_t lport, uint16_t rport, struct timeval *);
  
  /* void sctp_drain(void); */
  
  int sctp_destination_is_reachable(struct sctp_tcb *, struct sockaddr *);
  
  int sctp_swap_inpcb_for_listen(struct sctp_inpcb *inp);
  
  /*-
   * Null in last arg inpcb indicate run on ALL ep's. Specific inp in last arg
   * indicates run on ONLY assoc's of the specified endpoint.
   */
  int
  sctp_initiate_iterator(inp_func inpf,
  		       asoc_func af,
  		       inp_func inpe,
  		       uint32_t, uint32_t,
  		       uint32_t, void *,
  		       uint32_t,
  		       end_func ef,
  		       struct sctp_inpcb *,
  		       uint8_t co_off);
  #if defined(__FreeBSD__) && defined(SCTP_MCORE_INPUT) && defined(SMP)
  void
  sctp_queue_to_mcore(struct mbuf *m, int off, int cpu_to_use);
  
  #endif
  
  #ifdef INVARIANTS
  void
  sctp_validate_no_locks(struct sctp_inpcb *inp);
  #endif
  
  #endif				/* _KERNEL */
  #endif				/* !__sctp_pcb_h__ */
  