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      1 /*
      2  * CDDL HEADER START
      3  *
      4  * The contents of this file are subject to the terms of the
      5  * Common Development and Distribution License (the "License").
      6  * You may not use this file except in compliance with the License.
      7  *
      8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
      9  * or http://www.opensolaris.org/os/licensing.
     10  * See the License for the specific language governing permissions
     11  * and limitations under the License.
     12  *
     13  * When distributing Covered Code, include this CDDL HEADER in each
     14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
     15  * If applicable, add the following below this CDDL HEADER, with the
     16  * fields enclosed by brackets "[]" replaced with your own identifying
     17  * information: Portions Copyright [yyyy] [name of copyright owner]
     18  *
     19  * CDDL HEADER END
     20  */
     21 /*
     22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
     23  * Use is subject to license terms.
     24  */
     25 /* Copyright (c) 1990 Mentat Inc. */
     26 
     27 #ifndef	_INET_TCP_H
     28 #define	_INET_TCP_H
     29 
     30 #ifdef	__cplusplus
     31 extern "C" {
     32 #endif
     33 
     34 #include <sys/inttypes.h>
     35 #include <netinet/ip6.h>
     36 #include <netinet/tcp.h>
     37 #include <sys/socket.h>
     38 #include <sys/socket_proto.h>
     39 #include <sys/md5.h>
     40 #include <inet/common.h>
     41 #include <inet/ip.h>
     42 #include <inet/ip6.h>
     43 #include <inet/mi.h>
     44 #include <inet/mib2.h>
     45 #include <inet/tcp_stack.h>
     46 #include <inet/tcp_sack.h>
     47 #include <inet/kssl/ksslapi.h>
     48 
     49 /* TCP states */
     50 #define	TCPS_CLOSED		-6
     51 #define	TCPS_IDLE		-5	/* idle (opened, but not bound) */
     52 #define	TCPS_BOUND		-4	/* bound, ready to connect or accept */
     53 #define	TCPS_LISTEN		-3	/* listening for connection */
     54 #define	TCPS_SYN_SENT		-2	/* active, have sent syn */
     55 #define	TCPS_SYN_RCVD		-1	/* have received syn (and sent ours) */
     56 /* states < TCPS_ESTABLISHED are those where connections not established */
     57 #define	TCPS_ESTABLISHED	0	/* established */
     58 #define	TCPS_CLOSE_WAIT		1	/* rcvd fin, waiting for close */
     59 /* states > TCPS_CLOSE_WAIT are those where user has closed */
     60 #define	TCPS_FIN_WAIT_1		2	/* have closed and sent fin */
     61 #define	TCPS_CLOSING		3	/* closed, xchd FIN, await FIN ACK */
     62 #define	TCPS_LAST_ACK		4	/* had fin and close; await FIN ACK */
     63 /* states > TCPS_CLOSE_WAIT && < TCPS_FIN_WAIT_2 await ACK of FIN */
     64 #define	TCPS_FIN_WAIT_2		5	/* have closed, fin is acked */
     65 #define	TCPS_TIME_WAIT		6	/* in 2*msl quiet wait after close */
     66 
     67 /*
     68  * Internal flags used in conjunction with the packet header flags.
     69  * Used in tcp_input_data to keep track of what needs to be done.
     70  */
     71 #define	TH_LIMIT_XMIT		0x0400	/* Limited xmit is needed */
     72 #define	TH_XMIT_NEEDED		0x0800	/* Window opened - send queued data */
     73 #define	TH_REXMIT_NEEDED	0x1000	/* Time expired for unacked data */
     74 #define	TH_ACK_NEEDED		0x2000	/* Send an ack now. */
     75 #define	TH_NEED_SACK_REXMIT	0x4000	/* Use SACK info to retransmission */
     76 #define	TH_ACK_TIMER_NEEDED	0x8000	/* Start the delayed ACK timer */
     77 #define	TH_ORDREL_NEEDED	0x10000	/* Generate an ordrel indication */
     78 #define	TH_MARKNEXT_NEEDED	0x20000	/* Data should have MSGMARKNEXT */
     79 #define	TH_SEND_URP_MARK	0x40000	/* Send up tcp_urp_mark_mp */
     80 
     81 /*
     82  * TCP sequence numbers are 32 bit integers operated
     83  * on with modular arithmetic.  These macros can be
     84  * used to compare such integers.
     85  */
     86 #define	SEQ_LT(a, b)	((int32_t)((a)-(b)) < 0)
     87 #define	SEQ_LEQ(a, b)	((int32_t)((a)-(b)) <= 0)
     88 #define	SEQ_GT(a, b)	((int32_t)((a)-(b)) > 0)
     89 #define	SEQ_GEQ(a, b)	((int32_t)((a)-(b)) >= 0)
     90 
     91 /* TCP Protocol header */
     92 typedef	struct tcphdr_s {
     93 	uint8_t		th_lport[2];	/* Source port */
     94 	uint8_t		th_fport[2];	/* Destination port */
     95 	uint8_t		th_seq[4];	/* Sequence number */
     96 	uint8_t		th_ack[4];	/* Acknowledgement number */
     97 	uint8_t		th_offset_and_rsrvd[1]; /* Offset to the packet data */
     98 	uint8_t		th_flags[1];
     99 	uint8_t		th_win[2];	/* Allocation number */
    100 	uint8_t		th_sum[2];	/* TCP checksum */
    101 	uint8_t		th_urp[2];	/* Urgent pointer */
    102 } tcph_t;
    103 
    104 #define	TCP_HDR_LENGTH(tcph) \
    105 	((((tcph_t *)tcph)->th_offset_and_rsrvd[0] >>2) &(0xF << 2))
    106 #define	TCP_MAX_COMBINED_HEADER_LENGTH	(60 + 60) /* Maxed out ip + tcp */
    107 #define	TCP_MAX_IP_OPTIONS_LENGTH	(60 - IP_SIMPLE_HDR_LENGTH)
    108 #define	TCP_MAX_HDR_LENGTH		60
    109 #define	TCP_MAX_TCP_OPTIONS_LENGTH	(60 - sizeof (tcpha_t))
    110 #define	TCP_MIN_HEADER_LENGTH		20
    111 #define	TCP_MAXWIN			65535
    112 #define	TCP_PORT_LEN			sizeof (in_port_t)
    113 #define	TCP_MAX_WINSHIFT		14
    114 #define	TCP_MAX_LARGEWIN		(TCP_MAXWIN << TCP_MAX_WINSHIFT)
    115 #define	TCP_MAX_LSO_LENGTH	(IP_MAXPACKET - TCP_MAX_COMBINED_HEADER_LENGTH)
    116 
    117 #define	TCPIP_HDR_LENGTH(mp, n)					\
    118 	(n) = IPH_HDR_LENGTH((mp)->b_rptr),			\
    119 	(n) += TCP_HDR_LENGTH((tcpha_t *)&(mp)->b_rptr[(n)])
    120 
    121 /* TCP Protocol header (used if the header is known to be 32-bit aligned) */
    122 typedef	struct tcphdra_s {
    123 	in_port_t	tha_lport;	/* Source port */
    124 	in_port_t	tha_fport;	/* Destination port */
    125 	uint32_t	tha_seq;	/* Sequence number */
    126 	uint32_t	tha_ack;	/* Acknowledgement number */
    127 	uint8_t tha_offset_and_reserved; /* Offset to the packet data */
    128 	uint8_t		tha_flags;
    129 	uint16_t	tha_win;	/* Allocation number */
    130 	uint16_t	tha_sum;	/* TCP checksum */
    131 	uint16_t	tha_urp;	/* Urgent pointer */
    132 } tcpha_t;
    133 
    134 struct conn_s;
    135 
    136 /*
    137  * Control structure for each open TCP stream,
    138  * defined only within the kernel or for a kmem user.
    139  * NOTE: tcp_reinit_values MUST have a line for each field in this structure!
    140  */
    141 #if (defined(_KERNEL) || defined(_KMEMUSER))
    142 
    143 typedef struct tcp_s {
    144 				/* Pointer to previous bind hash next. */
    145 	struct tcp_s	*tcp_time_wait_next;
    146 				/* Pointer to next T/W block */
    147 	struct tcp_s	*tcp_time_wait_prev;
    148 				/* Pointer to previous T/W next */
    149 	clock_t		tcp_time_wait_expire;
    150 
    151 	struct conn_s	*tcp_connp;
    152 	tcp_stack_t	*tcp_tcps;	/* Shortcut via conn_netstack */
    153 
    154 	int32_t	tcp_state;
    155 	int32_t	tcp_rcv_ws;		/* My window scale power */
    156 	int32_t	tcp_snd_ws;		/* Sender's window scale power */
    157 	uint32_t tcp_ts_recent;		/* Timestamp of earliest unacked */
    158 					/*  data segment */
    159 	clock_t	tcp_rto;		/* Round trip timeout */
    160 	clock_t	tcp_last_rcv_lbolt;
    161 				/* lbolt on last packet, used for PAWS */
    162 
    163 	uint32_t tcp_snxt;		/* Senders next seq num */
    164 	uint32_t tcp_swnd;		/* Senders window (relative to suna) */
    165 	uint32_t tcp_mss;		/* Max segment size */
    166 	uint32_t tcp_iss;		/* Initial send seq num */
    167 	uint32_t tcp_rnxt;		/* Seq we expect to recv next */
    168 	uint32_t tcp_rwnd;
    169 
    170 	/* Fields arranged in approximate access order along main paths */
    171 	mblk_t	*tcp_xmit_head;		/* Head of rexmit list */
    172 	mblk_t	*tcp_xmit_last;		/* last valid data seen by tcp_wput */
    173 	mblk_t	*tcp_xmit_tail;		/* Last rexmit data sent */
    174 	uint32_t tcp_unsent;		/* # of bytes in hand that are unsent */
    175 	uint32_t tcp_xmit_tail_unsent;	/* # of unsent bytes in xmit_tail */
    176 
    177 	uint32_t tcp_suna;		/* Sender unacknowledged */
    178 	uint32_t tcp_rexmit_nxt;	/* Next rexmit seq num */
    179 	uint32_t tcp_rexmit_max;	/* Max retran seq num */
    180 	int32_t	tcp_snd_burst;		/* Send burst factor */
    181 	uint32_t tcp_cwnd;		/* Congestion window */
    182 	int32_t tcp_cwnd_cnt;		/* cwnd cnt in congestion avoidance */
    183 
    184 	uint32_t tcp_ibsegs;		/* Inbound segments on this stream */
    185 	uint32_t tcp_obsegs;		/* Outbound segments on this stream */
    186 
    187 	uint32_t tcp_naglim;		/* Tunable nagle limit */
    188 	uint32_t	tcp_valid_bits;
    189 #define	TCP_ISS_VALID	0x1	/* Is the tcp_iss seq num active? */
    190 #define	TCP_FSS_VALID	0x2	/* Is the tcp_fss seq num active? */
    191 #define	TCP_URG_VALID	0x4	/* Is the tcp_urg seq num active? */
    192 #define	TCP_OFO_FIN_VALID 0x8	/* Has TCP received an out of order FIN? */
    193 
    194 
    195 
    196 	timeout_id_t	tcp_timer_tid;	/* Control block for timer service */
    197 	uchar_t	tcp_timer_backoff;	/* Backoff shift count. */
    198 	int64_t tcp_last_recv_time;	/* Last time we receive a segment. */
    199 	uint32_t tcp_init_cwnd;		/* Initial cwnd (start/restart) */
    200 
    201 	/* Following manipulated by TCP under squeue protection */
    202 	uint32_t
    203 		tcp_urp_last_valid : 1,	/* Is tcp_urp_last valid? */
    204 		tcp_hard_binding : 1,	/* TCP_DETACHED_NONEAGER */
    205 		tcp_fin_acked : 1,	/* Has our FIN been acked? */
    206 		tcp_fin_rcvd : 1,	/* Have we seen a FIN? */
    207 
    208 		tcp_fin_sent : 1,	/* Have we sent our FIN yet? */
    209 		tcp_ordrel_done : 1,	/* Have we sent the ord_rel upstream? */
    210 		tcp_detached : 1,	/* If we're detached from a stream */
    211 		tcp_zero_win_probe: 1,	/* Zero win probing is in progress */
    212 
    213 		tcp_loopback: 1,	/* src and dst are the same machine */
    214 		tcp_localnet: 1,	/* src and dst are on the same subnet */
    215 		tcp_syn_defense: 1,	/* For defense against SYN attack */
    216 #define	tcp_dontdrop	tcp_syn_defense
    217 		tcp_set_timer : 1,
    218 
    219 		tcp_active_open: 1,	/* This is a active open */
    220 		tcp_rexmit : 1,		/* TCP is retransmitting */
    221 		tcp_snd_sack_ok : 1,	/* Can use SACK for this connection */
    222 		tcp_hwcksum : 1,	/* The NIC is capable of hwcksum */
    223 
    224 		tcp_ip_forward_progress : 1,
    225 		tcp_ecn_ok : 1,		/* Can use ECN for this connection */
    226 		tcp_ecn_echo_on : 1,	/* Need to do ECN echo */
    227 		tcp_ecn_cwr_sent : 1,	/* ECN_CWR has been sent */
    228 
    229 		tcp_cwr : 1,		/* Cwnd has reduced recently */
    230 
    231 		tcp_pad_to_bit31 : 11;
    232 
    233 	/* Following manipulated by TCP under squeue protection */
    234 	uint32_t
    235 		tcp_snd_ts_ok  : 1,
    236 		tcp_snd_ws_ok  : 1,
    237 		tcp_reserved_port : 1,
    238 		tcp_in_free_list : 1,
    239 
    240 		tcp_snd_zcopy_on : 1,	/* xmit zero-copy enabled */
    241 		tcp_snd_zcopy_aware : 1, /* client is zero-copy aware */
    242 		tcp_xmit_zc_clean : 1,	/* the xmit list is free of zc-mblk */
    243 		tcp_wait_for_eagers : 1, /* Wait for eagers to disappear */
    244 
    245 		tcp_accept_error : 1,	/* Error during TLI accept */
    246 		tcp_send_discon_ind : 1, /* TLI accept err, send discon ind */
    247 		tcp_cork : 1,		/* tcp_cork option */
    248 		tcp_tconnind_started : 1, /* conn_ind message is being sent */
    249 
    250 		tcp_lso :1,		/* Lower layer is capable of LSO */
    251 		tcp_is_wnd_shrnk : 1, /* Window has shrunk */
    252 
    253 		tcp_pad_to_bit_31 : 18;
    254 
    255 	uint32_t	tcp_initial_pmtu; /* Initial outgoing Path MTU. */
    256 
    257 	mblk_t	*tcp_reass_head;	/* Out of order reassembly list head */
    258 	mblk_t	*tcp_reass_tail;	/* Out of order reassembly list tail */
    259 
    260 	tcp_sack_info_t	*tcp_sack_info;
    261 
    262 #define	tcp_pipe	tcp_sack_info->tcp_pipe
    263 #define	tcp_fack	tcp_sack_info->tcp_fack
    264 #define	tcp_sack_snxt	tcp_sack_info->tcp_sack_snxt
    265 #define	tcp_max_sack_blk	tcp_sack_info->tcp_max_sack_blk
    266 #define	tcp_num_sack_blk	tcp_sack_info->tcp_num_sack_blk
    267 #define	tcp_sack_list		tcp_sack_info->tcp_sack_list
    268 #define	tcp_num_notsack_blk	tcp_sack_info->tcp_num_notsack_blk
    269 #define	tcp_cnt_notsack_list	tcp_sack_info->tcp_cnt_notsack_list
    270 #define	tcp_notsack_list		tcp_sack_info->tcp_notsack_list
    271 
    272 	mblk_t	*tcp_rcv_list;		/* Queued until push, urgent data, */
    273 	mblk_t	*tcp_rcv_last_head;	/* optdata, or the count exceeds */
    274 	mblk_t	*tcp_rcv_last_tail;	/* tcp_rcv_push_wait. */
    275 	uint32_t tcp_rcv_cnt;		/* tcp_rcv_list is b_next chain. */
    276 
    277 	uint32_t tcp_cwnd_ssthresh;	/* Congestion window */
    278 	uint32_t tcp_cwnd_max;
    279 	uint32_t tcp_csuna;		/* Clear (no rexmits in window) suna */
    280 
    281 	clock_t	tcp_rtt_sa;		/* Round trip smoothed average */
    282 	clock_t	tcp_rtt_sd;		/* Round trip smoothed deviation */
    283 	clock_t	tcp_rtt_update;		/* Round trip update(s) */
    284 	clock_t tcp_ms_we_have_waited;	/* Total retrans time */
    285 
    286 	uint32_t tcp_swl1;		/* These help us avoid using stale */
    287 	uint32_t tcp_swl2;		/*  packets to update state */
    288 
    289 	uint32_t tcp_rack;		/* Seq # we have acked */
    290 	uint32_t tcp_rack_cnt;		/* # of segs we have deferred ack */
    291 	uint32_t tcp_rack_cur_max;	/* # of segs we may defer ack for now */
    292 	uint32_t tcp_rack_abs_max;	/* # of segs we may defer ack ever */
    293 	timeout_id_t	tcp_ack_tid;	/* Delayed ACK timer ID */
    294 	timeout_id_t	tcp_push_tid;	/* Push timer ID */
    295 
    296 	uint32_t tcp_max_swnd;		/* Maximum swnd we have seen */
    297 
    298 	struct tcp_s *tcp_listener;	/* Our listener */
    299 
    300 	uint32_t tcp_irs;		/* Initial recv seq num */
    301 	uint32_t tcp_fss;		/* Final/fin send seq num */
    302 	uint32_t tcp_urg;		/* Urgent data seq num */
    303 
    304 	clock_t	tcp_first_timer_threshold;  /* When to prod IP */
    305 	clock_t	tcp_second_timer_threshold; /* When to give up completely */
    306 	clock_t	tcp_first_ctimer_threshold; /* 1st threshold while connecting */
    307 	clock_t tcp_second_ctimer_threshold; /* 2nd ... while connecting */
    308 
    309 	uint32_t tcp_urp_last;		/* Last urp for which signal sent */
    310 	mblk_t	*tcp_urp_mp;		/* T_EXDATA_IND for urgent byte */
    311 	mblk_t	*tcp_urp_mark_mp;	/* zero-length marked/unmarked msg */
    312 
    313 	int tcp_conn_req_cnt_q0;	/* # of conn reqs in SYN_RCVD */
    314 	int tcp_conn_req_cnt_q;	/* # of conn reqs in ESTABLISHED */
    315 	int tcp_conn_req_max;	/* # of ESTABLISHED conn reqs allowed */
    316 	t_scalar_t tcp_conn_req_seqnum;	/* Incrementing pending conn req ID */
    317 #define	tcp_ip_addr_cache	tcp_reass_tail
    318 					/* Cache ip addresses that */
    319 					/* complete the 3-way handshake */
    320 	kmutex_t  tcp_eager_lock;
    321 	struct tcp_s *tcp_eager_next_q; /* next eager in ESTABLISHED state */
    322 	struct tcp_s *tcp_eager_last_q;	/* last eager in ESTABLISHED state */
    323 	struct tcp_s *tcp_eager_next_q0; /* next eager in SYN_RCVD state */
    324 	struct tcp_s *tcp_eager_prev_q0; /* prev eager in SYN_RCVD state */
    325 					/* all eagers form a circular list */
    326 	boolean_t tcp_conn_def_q0;	/* move from q0 to q deferred */
    327 
    328 	union {
    329 	    mblk_t *tcp_eager_conn_ind; /* T_CONN_IND waiting for 3rd ack. */
    330 	    mblk_t *tcp_opts_conn_req; /* T_CONN_REQ w/ options processed */
    331 	} tcp_conn;
    332 	uint32_t tcp_syn_rcvd_timeout;	/* How many SYN_RCVD timeout in q0 */
    333 
    334 	/* TCP Keepalive Timer members */
    335 	int32_t	tcp_ka_last_intrvl;	/* Last probe interval */
    336 	timeout_id_t tcp_ka_tid;	/* Keepalive timer ID */
    337 	uint32_t tcp_ka_interval;	/* Keepalive interval */
    338 	uint32_t tcp_ka_abort_thres;	/* Keepalive abort threshold */
    339 
    340 	int32_t	tcp_client_errno;	/* How the client screwed up */
    341 
    342 	/*
    343 	 * The header template lives in conn_ht_iphc allocated by tcp_build_hdrs
    344 	 * We maintain three pointers into conn_ht_iphc.
    345 	 */
    346 	ipha_t	*tcp_ipha;		/* IPv4 header in conn_ht_iphc */
    347 	ip6_t	*tcp_ip6h;		/* IPv6 header in conn_ht_iphc */
    348 	tcpha_t	*tcp_tcpha;		/* TCP header in conn_ht_iphc */
    349 
    350 	uint16_t tcp_last_sent_len;	/* Record length for nagle */
    351 	uint16_t tcp_dupack_cnt;	/* # of consequtive duplicate acks */
    352 
    353 	kmutex_t	*tcp_acceptor_lockp;	/* Ptr to tf_lock */
    354 
    355 	mblk_t		*tcp_ordrel_mp;		/* T_ordrel_ind mblk */
    356 	t_uscalar_t	tcp_acceptor_id;	/* ACCEPTOR_id */
    357 
    358 	int		tcp_ipsec_overhead;
    359 
    360 	uint_t		tcp_recvifindex; /* Last received IPV6_RCVPKTINFO */
    361 	uint_t		tcp_recvhops;	/* Last received IPV6_RECVHOPLIMIT */
    362 	uint_t		tcp_recvtclass;	/* Last received IPV6_RECVTCLASS */
    363 	ip6_hbh_t	*tcp_hopopts;	/* Last received IPV6_RECVHOPOPTS */
    364 	ip6_dest_t	*tcp_dstopts;	/* Last received IPV6_RECVDSTOPTS */
    365 	ip6_dest_t	*tcp_rthdrdstopts; /* Last recv IPV6_RECVRTHDRDSTOPTS */
    366 	ip6_rthdr_t	*tcp_rthdr;	/* Last received IPV6_RECVRTHDR */
    367 	uint_t		tcp_hopoptslen;
    368 	uint_t		tcp_dstoptslen;
    369 	uint_t		tcp_rthdrdstoptslen;
    370 	uint_t		tcp_rthdrlen;
    371 
    372 	mblk_t		*tcp_timercache;
    373 
    374 	kmutex_t	tcp_closelock;
    375 	kcondvar_t	tcp_closecv;
    376 	uint8_t		tcp_closed;
    377 	uint8_t		tcp_closeflags;
    378 	uint8_t		tcp_cleandeathtag;
    379 	mblk_t		tcp_closemp;
    380 	timeout_id_t	tcp_linger_tid;	/* Linger timer ID */
    381 
    382 	struct tcp_s *tcp_acceptor_hash; /* Acceptor hash chain */
    383 	struct tcp_s **tcp_ptpahn; /* Pointer to previous accept hash next. */
    384 	struct tcp_s *tcp_bind_hash; /* Bind hash chain */
    385 	struct tcp_s *tcp_bind_hash_port; /* tcp_t's bound to the same lport */
    386 	struct tcp_s **tcp_ptpbhn;
    387 
    388 	uint_t		tcp_maxpsz_multiplier;
    389 
    390 	uint32_t	tcp_lso_max; /* maximum LSO payload */
    391 
    392 	uint32_t	tcp_ofo_fin_seq; /* Recv out of order FIN seq num */
    393 	uint32_t	tcp_cwr_snd_max;
    394 
    395 	struct tcp_s *tcp_saved_listener;	/* saved value of listener */
    396 
    397 	uint32_t	tcp_in_ack_unsent;	/* ACK for unsent data cnt. */
    398 
    399 	/*
    400 	 * All fusion-related fields are protected by squeue.
    401 	 */
    402 	struct tcp_s *tcp_loopback_peer;	/* peer tcp for loopback */
    403 	mblk_t	*tcp_fused_sigurg_mp;		/* M_PCSIG mblk for SIGURG */
    404 
    405 	uint32_t
    406 		tcp_fused : 1,		/* loopback tcp in fusion mode */
    407 		tcp_unfusable : 1,	/* fusion not allowed on endpoint */
    408 		tcp_fused_sigurg : 1,	/* send SIGURG upon draining */
    409 
    410 		tcp_fuse_to_bit_31 : 29;
    411 
    412 	kmutex_t tcp_non_sq_lock;
    413 
    414 	/*
    415 	 * This variable is accessed without any lock protection
    416 	 * and therefore must not be declared as a bit field along
    417 	 * with the rest which require such condition.
    418 	 */
    419 	boolean_t	tcp_issocket;	/* this is a socket tcp */
    420 
    421 	/* protected by the tcp_non_sq_lock lock */
    422 	uint32_t	tcp_squeue_bytes;
    423 	/*
    424 	 * Kernel SSL session information
    425 	 */
    426 	boolean_t		tcp_kssl_pending; /* waiting for 1st SSL rec. */
    427 	boolean_t		tcp_kssl_inhandshake; /* during SSL handshake */
    428 	kssl_ent_t		tcp_kssl_ent;	/* SSL table entry */
    429 	kssl_ctx_t		tcp_kssl_ctx;	/* SSL session */
    430 
    431 	/*
    432 	 * tcp_closemp_used is protected by listener's tcp_eager_lock
    433 	 * when used for eagers. When used for a tcp in TIME_WAIT state
    434 	 * or in tcp_close(), it is not protected by any lock as we
    435 	 * do not expect any other thread to use it concurrently.
    436 	 * We do allow re-use of tcp_closemp in tcp_time_wait_collector()
    437 	 * and tcp_close() but not concurrently.
    438 	 */
    439 	boolean_t tcp_closemp_used;
    440 
    441 	/*
    442 	 * previous and next eagers in the list of droppable eagers. See
    443 	 * the comments before MAKE_DROPPABLE(). These pointers are
    444 	 * protected by listener's tcp_eager_lock.
    445 	 */
    446 	struct tcp_s	*tcp_eager_prev_drop_q0;
    447 	struct tcp_s	*tcp_eager_next_drop_q0;
    448 
    449 	/*
    450 	 * Have we flow controlled xmitter?
    451 	 * This variable can be modified outside the squeue and hence must
    452 	 * not be declared as a bit field along with the rest that are
    453 	 * modified only within the squeue.
    454 	 * protected by the tcp_non_sq_lock lock.
    455 	 */
    456 	boolean_t	tcp_flow_stopped;
    457 
    458 	/*
    459 	 * Sender's next sequence number at the time the window was shrunk.
    460 	 */
    461 	uint32_t	tcp_snxt_shrunk;
    462 
    463 	/*
    464 	 * Socket generation number which is bumped when a connection attempt
    465 	 * is initiated. Its main purpose is to ensure that the socket does not
    466 	 * miss the asynchronous connected/disconnected notification.
    467 	 */
    468 	sock_connid_t	tcp_connid;
    469 
    470 	/* mblk_t used to enter TCP's squeue from the service routine. */
    471 	mblk_t		*tcp_rsrv_mp;
    472 	/* Mutex for accessing tcp_rsrv_mp */
    473 	kmutex_t	tcp_rsrv_mp_lock;
    474 
    475 #ifdef DEBUG
    476 	pc_t			tcmp_stk[15];
    477 #endif
    478 } tcp_t;
    479 
    480 #ifdef DEBUG
    481 #define	TCP_DEBUG_GETPCSTACK(buffer, depth)	((void) getpcstack(buffer, \
    482 						    depth))
    483 #else
    484 #define	TCP_DEBUG_GETPCSTACK(buffer, depth)
    485 #endif
    486 
    487 extern void 	tcp_free(tcp_t *tcp);
    488 extern void	tcp_ddi_g_init(void);
    489 extern void	tcp_ddi_g_destroy(void);
    490 extern void	tcp_xmit_listeners_reset(mblk_t *, ip_recv_attr_t *,
    491     ip_stack_t *, conn_t *);
    492 extern void	tcp_input_listener(void *arg, mblk_t *mp, void *arg2,
    493     ip_recv_attr_t *);
    494 extern void	tcp_input_listener_unbound(void *arg, mblk_t *mp, void *arg2,
    495     ip_recv_attr_t *);
    496 extern void	tcp_input_data(void *arg, mblk_t *mp, void *arg2,
    497     ip_recv_attr_t *);
    498 extern void 	*tcp_get_conn(void *arg, tcp_stack_t *);
    499 extern void	tcp_time_wait_collector(void *arg);
    500 extern mblk_t	*tcp_snmp_get(queue_t *, mblk_t *);
    501 extern int	tcp_snmp_set(queue_t *, int, int, uchar_t *, int len);
    502 extern mblk_t	*tcp_xmit_mp(tcp_t *tcp, mblk_t *mp, int32_t max_to_send,
    503 		    int32_t *offset, mblk_t **end_mp, uint32_t seq,
    504 		    boolean_t sendall, uint32_t *seg_len, boolean_t rexmit);
    505 
    506 /*
    507  * The TCP Fanout structure.
    508  * The hash tables and their linkage (tcp_*_hash_next, tcp_ptp*hn) are
    509  * protected by the per-bucket tf_lock. Each tcp_t
    510  * inserted in the list points back at this lock using tcp_*_lockp.
    511  *
    512  * The listener and acceptor hash queues are lists of tcp_t.
    513  */
    514 /* listener hash and acceptor hash queue head */
    515 typedef struct tf_s {
    516 	tcp_t		*tf_tcp;
    517 	kmutex_t	tf_lock;
    518 } tf_t;
    519 #endif	/* (defined(_KERNEL) || defined(_KMEMUSER)) */
    520 
    521 /* Contract private interface between TCP and Clustering. */
    522 
    523 #define	CL_TCPI_V1	1	/* cl_tcpi_version number */
    524 
    525 typedef struct cl_tcp_info_s {
    526 	ushort_t	cl_tcpi_version;	/* cl_tcp_info_t's version no */
    527 	ushort_t	cl_tcpi_ipversion;	/* IP version */
    528 	int32_t		cl_tcpi_state;		/* TCP state */
    529 	in_port_t	cl_tcpi_lport;		/* Local port */
    530 	in_port_t	cl_tcpi_fport;		/* Remote port */
    531 	in6_addr_t	cl_tcpi_laddr_v6;	/* Local IP address */
    532 	in6_addr_t	cl_tcpi_faddr_v6;	/* Remote IP address */
    533 #ifdef _KERNEL
    534 /* Note: V4_PART_OF_V6 is meant to be used only for _KERNEL defined stuff */
    535 #define	cl_tcpi_laddr	V4_PART_OF_V6(cl_tcpi_laddr_v6)
    536 #define	cl_tcpi_faddr	V4_PART_OF_V6(cl_tcpi_faddr_v6)
    537 
    538 #endif	/* _KERNEL */
    539 } cl_tcp_info_t;
    540 
    541 /*
    542  * Hook functions to enable cluster networking
    543  * On non-clustered systems these vectors must always be NULL.
    544  */
    545 extern void	(*cl_inet_listen)(netstackid_t, uint8_t, sa_family_t,
    546 		    uint8_t *, in_port_t, void *);
    547 extern void	(*cl_inet_unlisten)(netstackid_t, uint8_t, sa_family_t,
    548 		    uint8_t *, in_port_t, void *);
    549 
    550 /*
    551  * Contracted Consolidation Private ioctl for aborting TCP connections.
    552  * In order to keep the offsets and size of the structure the same between
    553  * a 32-bit application and a 64-bit amd64 kernel, we use a #pragma
    554  * pack(4).
    555  */
    556 #define	TCP_IOC_ABORT_CONN	(('T' << 8) + 91)
    557 
    558 #if _LONG_LONG_ALIGNMENT == 8 && _LONG_LONG_ALIGNMENT_32 == 4
    559 #pragma pack(4)
    560 #endif
    561 
    562 typedef struct tcp_ioc_abort_conn_s {
    563 	struct sockaddr_storage ac_local;	/* local addr and port */
    564 	struct sockaddr_storage ac_remote;	/* remote addr and port */
    565 	int32_t ac_start;			/* start state */
    566 	int32_t ac_end;				/* end state  */
    567 	int32_t ac_zoneid;			/* zoneid */
    568 } tcp_ioc_abort_conn_t;
    569 
    570 #if _LONG_LONG_ALIGNMENT == 8 && _LONG_LONG_ALIGNMENT_32 == 4
    571 #pragma pack()
    572 #endif
    573 
    574 #ifdef	__cplusplus
    575 }
    576 #endif
    577 
    578 #endif	/* _INET_TCP_H */
    579