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      1 /*
      2  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
      3  * Use is subject to license terms.
      4  */
      5 
      6 /*
      7  * Copyright (c) 1982, 1986 Regents of the University of California.
      8  * All rights reserved. The Berkeley software License Agreement
      9  * specifies the terms and conditions for redistribution.
     10  */
     11 
     12 #ifndef _TCP_INET_H
     13 #define	_TCP_INET_H
     14 
     15 #pragma ident	"%Z%%M%	%I%	%E% SMI"
     16 
     17 #ifdef	__cplusplus
     18 extern "C" {
     19 #endif
     20 
     21 #include "tcp_sack.h"
     22 
     23 /* TCP states */
     24 #define	TCPS_ALL_ACKED		-7	/* Internal state for retransmissions */
     25 #define	TCPS_CLOSED		-6
     26 #define	TCPS_IDLE		-5	/* idle (opened, but not bound) */
     27 #define	TCPS_BOUND		-4	/* bound, ready to connect or accept */
     28 #define	TCPS_LISTEN		-3	/* listening for connection */
     29 #define	TCPS_SYN_SENT		-2	/* active, have sent syn */
     30 #define	TCPS_SYN_RCVD		-1	/* have received syn (and sent ours) */
     31 /* states < TCPS_ESTABLISHED are those where connections not established */
     32 #define	TCPS_ESTABLISHED	0	/* established */
     33 #define	TCPS_CLOSE_WAIT		1	/* rcvd fin, waiting for close */
     34 /* states > TCPS_CLOSE_WAIT are those where user has closed */
     35 #define	TCPS_FIN_WAIT_1		2	/* have closed and sent fin */
     36 #define	TCPS_CLOSING		3	/* closed, xchd FIN, await FIN ACK */
     37 #define	TCPS_LAST_ACK		4	/* had fin and close; await FIN ACK */
     38 /* states > TCPS_CLOSE_WAIT && < TCPS_FIN_WAIT_2 await ACK of FIN */
     39 #define	TCPS_FIN_WAIT_2		5	/* have closed, fin is acked */
     40 #define	TCPS_TIME_WAIT		6	/* in 2*msl quiet wait after close */
     41 
     42 /*
     43  * Internal flags used in conjunction with the packet header flags.
     44  * Used in tcp_rput_data to keep track of what needs to be done.
     45  */
     46 #define	TH_LIMIT_XMIT		0x0400	/* Limited xmit is needed */
     47 #define	TH_XMIT_NEEDED		0x0800	/* Window opened - send queued data */
     48 #define	TH_REXMIT_NEEDED	0x1000	/* Time expired for unacked data */
     49 #define	TH_ACK_NEEDED		0x2000	/* Send an ack now. */
     50 #define	TH_NEED_SACK_REXMIT	0x4000	/* Use SACK info to retransmission */
     51 #define	TH_TIMER_NEEDED 0x8000	/* Start the delayed ack/push bit timer */
     52 
     53 /*
     54  * Special Magic number used by TCP to issue a callback to recvfrom() in the
     55  * form of a dummy inetgram.
     56  */
     57 #define	TCP_CALLB_MAGIC_ID	0xFFFF
     58 
     59 /*
     60  * TCP sequence numbers are 32 bit integers operated
     61  * on with modular arithmetic.  These macros can be
     62  * used to compare such integers.
     63  */
     64 #define	SEQ_LT(a, b)	((int32_t)((a)-(b)) < 0)
     65 #define	SEQ_LEQ(a, b)	((int32_t)((a)-(b)) <= 0)
     66 #define	SEQ_GT(a, b)	((int32_t)((a)-(b)) > 0)
     67 #define	SEQ_GEQ(a, b)	((int32_t)((a)-(b)) >= 0)
     68 
     69 /* TCP Protocol header */
     70 typedef	struct tcphdr_s {
     71 	uint8_t		th_lport[2];	/* Source port */
     72 	uint8_t		th_fport[2];	/* Destination port */
     73 	uint8_t		th_seq[4];	/* Sequence number */
     74 	uint8_t		th_ack[4];	/* Acknowledgement number */
     75 	uint8_t		th_offset_and_rsrvd[1]; /* Offset to the packet data */
     76 	uint8_t		th_flags[1];
     77 	uint8_t		th_win[2];	/* Allocation number */
     78 	uint8_t		th_sum[2];	/* TCP checksum */
     79 	uint8_t		th_urp[2];	/* Urgent pointer */
     80 } tcph_t;
     81 
     82 #define	TCP_HDR_LENGTH(tcph) (((tcph)->th_offset_and_rsrvd[0] >>2) &(0xF << 2))
     83 #define	TCP_MAX_COMBINED_HEADER_LENGTH	(60 + 60) /* Maxed out ip + tcp */
     84 #define	TCP_MAX_IP_OPTIONS_LENGTH	(60 - IP_SIMPLE_HDR_LENGTH)
     85 #define	TCP_MAX_HDR_LENGTH		60
     86 #define	TCP_MAX_TCP_OPTIONS_LENGTH	(60 - sizeof (tcph_t))
     87 #define	TCP_MIN_HEADER_LENGTH		20
     88 #define	TCP_MAXWIN			65535
     89 #define	TCP_PORT_LEN			sizeof (in_port_t)
     90 #define	TCP_MAX_WINSHIFT		14
     91 #define	TCP_MAX_LARGEWIN		(TCP_MAXWIN << TCP_MAX_WINSHIFT)
     92 
     93 #define	TCPIP_HDR_LENGTH(mp, n)					\
     94 	(n) = IPH_HDR_LENGTH((mp)->b_rptr),			\
     95 	(n) += TCP_HDR_LENGTH((tcph_t *)&(mp)->b_rptr[(n)])
     96 
     97 /* TCP Protocol header (used if the header is known to be 32-bit aligned) */
     98 typedef	struct tcphdra_s {
     99 	in_port_t	tha_lport;	/* Source port */
    100 	in_port_t	tha_fport;	/* Destination port */
    101 	uint32_t	tha_seq;	/* Sequence number */
    102 	uint32_t	tha_ack;	/* Acknowledgement number */
    103 	uint8_t tha_offset_and_reserved; /* Offset to the packet data */
    104 	uint8_t		tha_flags;
    105 	uint16_t	tha_win;	/* Allocation number */
    106 	uint16_t	tha_sum;	/* TCP checksum */
    107 	uint16_t	tha_urp;	/* Urgent pointer */
    108 } tcpha_t;
    109 
    110 typedef struct tcp_s {
    111 	struct tcp_s *tcp_time_wait_next; /* Next TCP in TIME_WAIT list */
    112 	struct tcp_s *tcp_time_wait_prev; /* Prev TCP in TIME_WAIT list */
    113 	uint32_t tcp_max_swnd;		/* Maximum swnd we have seen */
    114 	uint32_t tcp_suna;		/* Sender unacknowledged */
    115 	uint32_t tcp_csuna;		/* Clear (no rexmits in window) suna */
    116 	uint32_t tcp_snxt;		/* Senders next seq num */
    117 	uint32_t tcp_swnd;		/* Senders window (relative to suna) */
    118 	uint32_t tcp_mss;		/* Max segment size */
    119 	uint32_t tcp_iss;		/* Initial send seq num */
    120 	uint32_t tcp_rnxt;		/* Seq we expect to recv next */
    121 	uint32_t tcp_rwnd;		/* Current receive window */
    122 	uint32_t tcp_rwnd_max;		/* Max receive window */
    123 
    124 	uint32_t tcp_irs;		/* Initial recv seq num */
    125 	uint32_t tcp_fss;		/* Final/fin send seq num */
    126 
    127 	uint32_t tcp_swl1;		/* These help us avoid using stale */
    128 	uint32_t tcp_swl2;		/*  packets to update state */
    129 
    130 	uint32_t tcp_cwnd;		/* Congestion window */
    131 	int32_t tcp_cwnd_cnt;		/* cwnd cnt in congestion avoidance */
    132 	uint32_t tcp_cwnd_ssthresh;	/* Congestion window */
    133 	uint32_t tcp_cwnd_max;
    134 
    135 	int32_t	tcp_snd_burst;		/* Send burst factor */
    136 
    137 	int32_t	tcp_state;
    138 	int32_t	tcp_rcv_ws;		/* My window scale power */
    139 	int32_t	tcp_snd_ws;		/* Sender's window scale power */
    140 	uint32_t tcp_ts_recent;	/* Timestamp of earliest unacked */
    141 					/*  data segment */
    142 
    143 	uint32_t	tcp_if_mtu;	/* Outgoing interface MTU. */
    144 
    145 	uint32_t	tcp_rtt_sa;	/* Round trip smoothed average */
    146 	uint32_t	tcp_rtt_sd;	/* Round trip smoothed deviation */
    147 	uint32_t	tcp_rtt_update;		/* Round trip update(s) */
    148 	uint32_t 	tcp_ms_we_have_waited;	/* Total retrans time */
    149 	uint32_t	tcp_rto;	/* Round trip timeout */
    150 	uint32_t	tcp_rto_timeout;	/* RTT timeout time */
    151 	uint32_t	tcp_time_wait_expire;
    152 				/* time in hz when t/w expires */
    153 	uint32_t	tcp_last_rcv_lbolt;
    154 				/* lbolt on last packet, used for PAWS */
    155 	int	tcp_lingertime;		/* Close linger time (in seconds) */
    156 
    157 	uint32_t	tcp_first_timer_threshold;  /* When to prod IP */
    158 	uint32_t tcp_second_timer_threshold; /* When to give up completely */
    159 	uint32_t tcp_first_ctimer_threshold; /* 1st threshold when connecting */
    160 	uint32_t tcp_second_ctimer_threshold; /* 2nd ... while connecting */
    161 
    162 	uint32_t tcp_rexmit_nxt;	/* Next rexmit seq num */
    163 	uint32_t tcp_rexmit_max;	/* Max retran seq num */
    164 
    165 	uint32_t tcp_naglim;		/* Tunable nagle limit */
    166 	uint32_t	tcp_valid_bits;
    167 #define	TCP_ISS_VALID	0x1	/* Is the tcp_iss seq num active? */
    168 #define	TCP_FSS_VALID	0x2	/* Is the tcp_fss seq num active? */
    169 #define	TCP_URG_VALID	0x4	/* Is the tcp_urg seq num active? */
    170 #define	TCP_OFO_FIN_VALID 0x8	/* Has TCP received an out of order FIN? */
    171 
    172 	int32_t	tcp_xmit_hiwater;	/* Send buffer high water mark. */
    173 	int32_t	tcp_xmit_lowater;	/* Send buffer low water mark. */
    174 
    175 	uchar_t	tcp_timer_backoff;	/* Backoff shift count. */
    176 	uint32_t tcp_last_recv_time;	/* Last time we receive a segment. */
    177 
    178 	/* Fields arranged in approximate access order along main paths */
    179 	mblk_t	*tcp_xmit_head;		/* Head of rexmit list */
    180 	mblk_t	*tcp_xmit_last;		/* last valid data seen by tcp_wput */
    181 	uint32_t tcp_unsent;		/* # of bytes in hand that are unsent */
    182 	mblk_t	*tcp_xmit_tail;		/* Last rexmit data sent */
    183 	uint32_t tcp_xmit_tail_unsent;	/* # of unsent bytes in xmit_tail */
    184 	mblk_t	*tcp_rcv_list;		/* Queued until push or exceed */
    185 	mblk_t	*tcp_rcv_last_tail;	/* tcp_rcv_push_wait. */
    186 	uint32_t tcp_rcv_cnt;		/* tcp_rcv_list is b_next chain. */
    187 
    188 	uint32_t tcp_rack;		/* Seq # we have acked */
    189 	uint32_t tcp_rack_cnt;		/* # of bytes we have deferred ack */
    190 
    191 	mblk_t	*tcp_reass_head;	 /* Out of order reassembly list head */
    192 	mblk_t	*tcp_reass_tail;	 /* Out of order reassembly list tail */
    193 
    194 	tcp_sack_info_t	*tcp_sack_info;
    195 
    196 #define	tcp_pipe	tcp_sack_info->tcp_pipe
    197 #define	tcp_fack	tcp_sack_info->tcp_fack
    198 #define	tcp_sack_snxt	tcp_sack_info->tcp_sack_snxt
    199 #define	tcp_max_sack_blk	tcp_sack_info->tcp_max_sack_blk
    200 #define	tcp_num_sack_blk	tcp_sack_info->tcp_num_sack_blk
    201 #define	tcp_sack_list		tcp_sack_info->tcp_sack_list
    202 #define	tcp_num_notsack_blk	tcp_sack_info->tcp_num_notsack_blk
    203 #define	tcp_cnt_notsack_list	tcp_sack_info->tcp_cnt_notsack_list
    204 #define	tcp_notsack_list		tcp_sack_info->tcp_notsack_list
    205 
    206 	int tcp_conn_req_cnt_q0;	/* # of conn reqs in SYN_RCVD */
    207 	int tcp_conn_req_cnt_q;	/* # of conn reqs in ESTABLISHED */
    208 	int tcp_conn_req_max;	/* # of ESTABLISHED conn reqs allowed */
    209 
    210 	int	tcp_iphc_len;		/* actual allocated buffer size */
    211 	int32_t	tcp_hdr_len;		/* Byte len of combined TCP/IP hdr */
    212 	struct ip	*tcp_ipha;	/* IPv4 header in the buffer */
    213 	int	tcp_ip_hdr_len;		/* Byte len of our current IPvx hdr */
    214 	tcph_t	*tcp_tcph;		/* tcp header within combined hdr */
    215 	int32_t	tcp_tcp_hdr_len;	/* tcp header len within combined */
    216 
    217 	uint16_t tcp_last_sent_len;	/* Record length for nagle */
    218 	uint16_t tcp_dupack_cnt;	/* # of consequtive duplicate acks */
    219 
    220 	/*
    221 	 * Address family that app wishes returned addrsses to be in.
    222 	 * Currently taken from address family used in T_BIND_REQ, but
    223 	 * should really come from family used in original socket() call.
    224 	 * Value can be AF_INET or AF_INET6.
    225 	 */
    226 	uint_t	tcp_family;
    227 
    228 	uint32_t	tcp_ofo_fin_seq; /* Recv out of order FIN seq num */
    229 	uint32_t	tcp_cwr_snd_max;
    230 
    231 	uint32_t
    232 		tcp_fin_acked : 1,	/* Has our FIN been acked? */
    233 		tcp_fin_rcvd : 1,	/* Have we seen a FIN? */
    234 		tcp_fin_sent : 1,	/* Have we sent our FIN yet? */
    235 		tcp_useloopback : 1,	/* SO_USELOOPBACK "socket" option. */
    236 
    237 		tcp_conn_def_q0: 1,	/* move from q0 to q deferred */
    238 		tcp_zero_win_probe: 1,	/* Zero win probing is in progress */
    239 		tcp_set_timer : 1,
    240 		tcp_active_open: 1,	/* This is a active open */
    241 
    242 		tcp_timer_running: 1,	/* Retransmission timer running */
    243 		tcp_rexmit : 1,		/* TCP is retransmitting */
    244 		tcp_snd_sack_ok : 1,	/* Can use SACK for this connection */
    245 		tcp_ecn_ok : 1,		/* Can use ECN for this connection */
    246 
    247 		tcp_ecn_echo_on : 1,	/* Need to do ECN echo */
    248 		tcp_ecn_cwr_sent : 1,	/* ECN_CWR has been sent */
    249 		tcp_cwr : 1,		/* Cwnd has reduced recently */
    250 		tcp_snd_ts_ok  : 1,
    251 
    252 		tcp_snd_ws_ok  : 1,
    253 		tcp_linger : 1,
    254 		tcp_dontdrop : 1,
    255 		tcp_junk_fill_thru_bit_31 : 13;
    256 
    257 	char	*tcp_iphc;		/* Buffer holding tcp/ip hdr template */
    258 
    259 	in_addr_t	tcp_remote;	/* true remote address - needed for */
    260 					/* source routing. */
    261 	in_addr_t	tcp_bound_source;	/* IP address in bind_req */
    262 	/*
    263 	 * These fields contain the same information as tcp_tcph->th_*port.
    264 	 * However, the lookup functions can not use the header fields
    265 	 * since during IP option manipulation the tcp_tcph pointer
    266 	 * changes.
    267 	 */
    268 	union {
    269 		struct {
    270 			in_port_t	tcpu_fport;	/* Remote port */
    271 			in_port_t	tcpu_lport;	/* Local port */
    272 		} tcpu_ports1;
    273 		uint32_t		tcpu_ports2;	/* Rem port, */
    274 							/* local port */
    275 					/* Used for TCP_MATCH performance */
    276 	} tcp_tcpu;
    277 #define	tcp_fport	tcp_tcpu.tcpu_ports1.tcpu_fport
    278 #define	tcp_lport	tcp_tcpu.tcpu_ports1.tcpu_lport
    279 #define	tcp_ports	tcp_tcpu.tcpu_ports2
    280 	/*
    281 	 * IP format that packets transmitted from this struct should use.
    282 	 * Value can be IPV4_VERSION or IPV6_VERSION.  Determines whether
    283 	 * IP+TCP header template above stores an IPv4 or IPv6 header.
    284 	 */
    285 	ushort_t	tcp_ipversion;
    286 	int		tcp_client_errno;
    287 	struct tcp_s *tcp_eager_next_q; /* next eager in ESTABLISHED state */
    288 	struct tcp_s *tcp_eager_last_q;	/* last eager in ESTABLISHED state */
    289 	struct tcp_s *tcp_eager_next_q0; /* next eager in SYN_RCVD state */
    290 	struct tcp_s *tcp_eager_prev_q0; /* prev eager in SYN_RCVD state */
    291 	struct tcp_s *tcp_listener;	/* Our listener */
    292 } tcp_t;
    293 
    294 /* External TCP functions. */
    295 extern void tcp_socket_init(struct inetboot_socket *);
    296 extern int tcp_connect(int);
    297 extern int tcp_listen(int, int);
    298 extern int tcp_bind(int);
    299 extern int tcp_send(int, tcp_t *, const void *, int);
    300 extern int tcp_opt_set(tcp_t *, int, int, const void *, socklen_t);
    301 extern int tcp_accept(int, struct sockaddr *, socklen_t *);
    302 extern int tcp_shutdown(int);
    303 
    304 /* Exported for recvfrom */
    305 extern void tcp_rcv_drain_sock(int);
    306 
    307 /* Exported for stand/lib/sock/sock_test.c */
    308 extern void tcp_time_wait_report(void);
    309 
    310 #ifdef	__cplusplus
    311 }
    312 #endif
    313 
    314 #endif /* _TCP_INET_H */
    315