1/*-
2 * Copyright (c) 1982, 1986, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * @(#)tcp.h 8.1 (Berkeley) 6/10/93
| 1/*-
2 * Copyright (c) 1982, 1986, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * @(#)tcp.h 8.1 (Berkeley) 6/10/93
|
30 * $FreeBSD: head/sys/netinet/tcp.h 203343 2010-02-01 14:13:44Z luigi $
| 30 * $FreeBSD: head/sys/netinet/tcp.h 212653 2010-09-15 10:39:30Z andre $
|
31 */
32
33#ifndef _NETINET_TCP_H_
34#define _NETINET_TCP_H_
35
36#include <sys/cdefs.h>
37
38#if __BSD_VISIBLE
39
40typedef u_int32_t tcp_seq;
41
42#define tcp6_seq tcp_seq /* for KAME src sync over BSD*'s */
43#define tcp6hdr tcphdr /* for KAME src sync over BSD*'s */
44
45/*
46 * TCP header.
47 * Per RFC 793, September, 1981.
48 */
49struct tcphdr {
50 u_short th_sport; /* source port */
51 u_short th_dport; /* destination port */
52 tcp_seq th_seq; /* sequence number */
53 tcp_seq th_ack; /* acknowledgement number */
54#if BYTE_ORDER == LITTLE_ENDIAN
55 u_char th_x2:4, /* (unused) */
56 th_off:4; /* data offset */
57#endif
58#if BYTE_ORDER == BIG_ENDIAN
59 u_char th_off:4, /* data offset */
60 th_x2:4; /* (unused) */
61#endif
62 u_char th_flags;
63#define TH_FIN 0x01
64#define TH_SYN 0x02
65#define TH_RST 0x04
66#define TH_PUSH 0x08
67#define TH_ACK 0x10
68#define TH_URG 0x20
69#define TH_ECE 0x40
70#define TH_CWR 0x80
71#define TH_FLAGS (TH_FIN|TH_SYN|TH_RST|TH_PUSH|TH_ACK|TH_URG|TH_ECE|TH_CWR)
72#define PRINT_TH_FLAGS "\20\1FIN\2SYN\3RST\4PUSH\5ACK\6URG\7ECE\10CWR"
73
74 u_short th_win; /* window */
75 u_short th_sum; /* checksum */
76 u_short th_urp; /* urgent pointer */
77};
78
79#define TCPOPT_EOL 0
80#define TCPOLEN_EOL 1
81#define TCPOPT_PAD 0 /* padding after EOL */
82#define TCPOLEN_PAD 1
83#define TCPOPT_NOP 1
84#define TCPOLEN_NOP 1
85#define TCPOPT_MAXSEG 2
86#define TCPOLEN_MAXSEG 4
87#define TCPOPT_WINDOW 3
88#define TCPOLEN_WINDOW 3
89#define TCPOPT_SACK_PERMITTED 4
90#define TCPOLEN_SACK_PERMITTED 2
91#define TCPOPT_SACK 5
92#define TCPOLEN_SACKHDR 2
93#define TCPOLEN_SACK 8 /* 2*sizeof(tcp_seq) */
94#define TCPOPT_TIMESTAMP 8
95#define TCPOLEN_TIMESTAMP 10
96#define TCPOLEN_TSTAMP_APPA (TCPOLEN_TIMESTAMP+2) /* appendix A */
97#define TCPOPT_SIGNATURE 19 /* Keyed MD5: RFC 2385 */
98#define TCPOLEN_SIGNATURE 18
99
100/* Miscellaneous constants */
101#define MAX_SACK_BLKS 6 /* Max # SACK blocks stored at receiver side */
102#define TCP_MAX_SACK 4 /* MAX # SACKs sent in any segment */
103
104
105/*
| 31 */
32
33#ifndef _NETINET_TCP_H_
34#define _NETINET_TCP_H_
35
36#include <sys/cdefs.h>
37
38#if __BSD_VISIBLE
39
40typedef u_int32_t tcp_seq;
41
42#define tcp6_seq tcp_seq /* for KAME src sync over BSD*'s */
43#define tcp6hdr tcphdr /* for KAME src sync over BSD*'s */
44
45/*
46 * TCP header.
47 * Per RFC 793, September, 1981.
48 */
49struct tcphdr {
50 u_short th_sport; /* source port */
51 u_short th_dport; /* destination port */
52 tcp_seq th_seq; /* sequence number */
53 tcp_seq th_ack; /* acknowledgement number */
54#if BYTE_ORDER == LITTLE_ENDIAN
55 u_char th_x2:4, /* (unused) */
56 th_off:4; /* data offset */
57#endif
58#if BYTE_ORDER == BIG_ENDIAN
59 u_char th_off:4, /* data offset */
60 th_x2:4; /* (unused) */
61#endif
62 u_char th_flags;
63#define TH_FIN 0x01
64#define TH_SYN 0x02
65#define TH_RST 0x04
66#define TH_PUSH 0x08
67#define TH_ACK 0x10
68#define TH_URG 0x20
69#define TH_ECE 0x40
70#define TH_CWR 0x80
71#define TH_FLAGS (TH_FIN|TH_SYN|TH_RST|TH_PUSH|TH_ACK|TH_URG|TH_ECE|TH_CWR)
72#define PRINT_TH_FLAGS "\20\1FIN\2SYN\3RST\4PUSH\5ACK\6URG\7ECE\10CWR"
73
74 u_short th_win; /* window */
75 u_short th_sum; /* checksum */
76 u_short th_urp; /* urgent pointer */
77};
78
79#define TCPOPT_EOL 0
80#define TCPOLEN_EOL 1
81#define TCPOPT_PAD 0 /* padding after EOL */
82#define TCPOLEN_PAD 1
83#define TCPOPT_NOP 1
84#define TCPOLEN_NOP 1
85#define TCPOPT_MAXSEG 2
86#define TCPOLEN_MAXSEG 4
87#define TCPOPT_WINDOW 3
88#define TCPOLEN_WINDOW 3
89#define TCPOPT_SACK_PERMITTED 4
90#define TCPOLEN_SACK_PERMITTED 2
91#define TCPOPT_SACK 5
92#define TCPOLEN_SACKHDR 2
93#define TCPOLEN_SACK 8 /* 2*sizeof(tcp_seq) */
94#define TCPOPT_TIMESTAMP 8
95#define TCPOLEN_TIMESTAMP 10
96#define TCPOLEN_TSTAMP_APPA (TCPOLEN_TIMESTAMP+2) /* appendix A */
97#define TCPOPT_SIGNATURE 19 /* Keyed MD5: RFC 2385 */
98#define TCPOLEN_SIGNATURE 18
99
100/* Miscellaneous constants */
101#define MAX_SACK_BLKS 6 /* Max # SACK blocks stored at receiver side */
102#define TCP_MAX_SACK 4 /* MAX # SACKs sent in any segment */
103
104
105/*
|
106 * Default maximum segment size for TCP.
107 * With an IP MTU of 576, this is 536,
108 * but 512 is probably more convenient.
109 * This should be defined as MIN(512, IP_MSS - sizeof (struct tcpiphdr)).
| 106 * The default maximum segment size (MSS) to be used for new TCP connections
107 * when path MTU discovery is not enabled.
108 *
109 * RFC879 derives the default MSS from the largest datagram size hosts are
110 * minimally required to handle directly or through IP reassembly minus the
111 * size of the IP and TCP header. With IPv6 the minimum MTU is specified
112 * in RFC2460.
113 *
114 * For IPv4 the MSS is 576 - sizeof(struct tcpiphdr)
115 * For IPv6 the MSS is IPV6_MMTU - sizeof(struct ip6_hdr) - sizeof(struct tcphdr)
116 *
117 * We use explicit numerical definition here to avoid header pollution.
|
110 */
| 118 */
|
111#define TCP_MSS 512
| 119#define TCP_MSS 536
120#define TCP6_MSS 1220
121
|
112/*
| 122/*
|
113 * TCP_MINMSS is defined to be 216 which is fine for the smallest
114 * link MTU (256 bytes, AX.25 packet radio) in the Internet.
115 * However it is very unlikely to come across such low MTU interfaces
116 * these days (anno dato 2003).
117 * See tcp_subr.c tcp_minmss SYSCTL declaration for more comments.
118 * Setting this to "0" disables the minmss check.
| 123 * Limit the lowest MSS we accept from path MTU discovery and the TCP SYN MSS
124 * option. Allowing too low values of MSS can consume significant amounts of
125 * resources and be used as a form of a resource exhaustion attack.
126 * Connections requesting lower MSS values will be rounded up to this value
127 * and the IP_DF flag is cleared to allow fragmentation along the path.
128 *
129 * See tcp_subr.c tcp_minmss SYSCTL declaration for more comments. Setting
130 * it to "0" disables the minmss check.
131 *
132 * The default value is fine for the smallest official link MTU (256 bytes,
133 * AX.25 packet radio) in the Internet. However it is very unlikely to come
134 * across such low MTU interfaces these days (anno domini 2003).
|
119 */
120#define TCP_MINMSS 216
121
| 135 */
136#define TCP_MINMSS 216
137
|
122/*
123 * Default maximum segment size for TCP6.
124 * With an IP6 MSS of 1280, this is 1220,
125 * but 1024 is probably more convenient. (xxx kazu in doubt)
126 * This should be defined as MIN(1024, IP6_MSS - sizeof (struct tcpip6hdr))
127 */
128#define TCP6_MSS 1024
129
| |
130#define TCP_MAXWIN 65535 /* largest value for (unscaled) window */
131#define TTCP_CLIENT_SND_WND 4096 /* dflt send window for T/TCP client */
132
133#define TCP_MAX_WINSHIFT 14 /* maximum window shift */
134
135#define TCP_MAXBURST 4 /* maximum segments in a burst */
136
137#define TCP_MAXHLEN (0xf<<2) /* max length of header in bytes */
138#define TCP_MAXOLEN (TCP_MAXHLEN - sizeof(struct tcphdr))
139 /* max space left for options */
140#endif /* __BSD_VISIBLE */
141
142/*
143 * User-settable options (used with setsockopt).
144 */
145#define TCP_NODELAY 0x01 /* don't delay send to coalesce packets */
146#if __BSD_VISIBLE
147#define TCP_MAXSEG 0x02 /* set maximum segment size */
148#define TCP_NOPUSH 0x04 /* don't push last block of write */
149#define TCP_NOOPT 0x08 /* don't use TCP options */
150#define TCP_MD5SIG 0x10 /* use MD5 digests (RFC2385) */
151#define TCP_INFO 0x20 /* retrieve tcp_info structure */
152#define TCP_CONGESTION 0x40 /* get/set congestion control algorithm */
153
154#define TCP_CA_NAME_MAX 16 /* max congestion control name length */
155
156#define TCPI_OPT_TIMESTAMPS 0x01
157#define TCPI_OPT_SACK 0x02
158#define TCPI_OPT_WSCALE 0x04
159#define TCPI_OPT_ECN 0x08
160#define TCPI_OPT_TOE 0x10
161
162/*
163 * The TCP_INFO socket option comes from the Linux 2.6 TCP API, and permits
164 * the caller to query certain information about the state of a TCP
165 * connection. We provide an overlapping set of fields with the Linux
166 * implementation, but since this is a fixed size structure, room has been
167 * left for growth. In order to maximize potential future compatibility with
168 * the Linux API, the same variable names and order have been adopted, and
169 * padding left to make room for omitted fields in case they are added later.
170 *
171 * XXX: This is currently an unstable ABI/API, in that it is expected to
172 * change.
173 */
174struct tcp_info {
175 u_int8_t tcpi_state; /* TCP FSM state. */
176 u_int8_t __tcpi_ca_state;
177 u_int8_t __tcpi_retransmits;
178 u_int8_t __tcpi_probes;
179 u_int8_t __tcpi_backoff;
180 u_int8_t tcpi_options; /* Options enabled on conn. */
181 u_int8_t tcpi_snd_wscale:4, /* RFC1323 send shift value. */
182 tcpi_rcv_wscale:4; /* RFC1323 recv shift value. */
183
184 u_int32_t tcpi_rto; /* Retransmission timeout (usec). */
185 u_int32_t __tcpi_ato;
186 u_int32_t tcpi_snd_mss; /* Max segment size for send. */
187 u_int32_t tcpi_rcv_mss; /* Max segment size for receive. */
188
189 u_int32_t __tcpi_unacked;
190 u_int32_t __tcpi_sacked;
191 u_int32_t __tcpi_lost;
192 u_int32_t __tcpi_retrans;
193 u_int32_t __tcpi_fackets;
194
195 /* Times; measurements in usecs. */
196 u_int32_t __tcpi_last_data_sent;
197 u_int32_t __tcpi_last_ack_sent; /* Also unimpl. on Linux? */
198 u_int32_t tcpi_last_data_recv; /* Time since last recv data. */
199 u_int32_t __tcpi_last_ack_recv;
200
201 /* Metrics; variable units. */
202 u_int32_t __tcpi_pmtu;
203 u_int32_t __tcpi_rcv_ssthresh;
204 u_int32_t tcpi_rtt; /* Smoothed RTT in usecs. */
205 u_int32_t tcpi_rttvar; /* RTT variance in usecs. */
206 u_int32_t tcpi_snd_ssthresh; /* Slow start threshold. */
207 u_int32_t tcpi_snd_cwnd; /* Send congestion window. */
208 u_int32_t __tcpi_advmss;
209 u_int32_t __tcpi_reordering;
210
211 u_int32_t __tcpi_rcv_rtt;
212 u_int32_t tcpi_rcv_space; /* Advertised recv window. */
213
214 /* FreeBSD extensions to tcp_info. */
215 u_int32_t tcpi_snd_wnd; /* Advertised send window. */
216 u_int32_t tcpi_snd_bwnd; /* Bandwidth send window. */
217 u_int32_t tcpi_snd_nxt; /* Next egress seqno */
218 u_int32_t tcpi_rcv_nxt; /* Next ingress seqno */
219 u_int32_t tcpi_toe_tid; /* HWTID for TOE endpoints */
220
221 /* Padding to grow without breaking ABI. */
222 u_int32_t __tcpi_pad[29]; /* Padding. */
223};
224#endif
225
226#endif /* !_NETINET_TCP_H_ */
| 138#define TCP_MAXWIN 65535 /* largest value for (unscaled) window */
139#define TTCP_CLIENT_SND_WND 4096 /* dflt send window for T/TCP client */
140
141#define TCP_MAX_WINSHIFT 14 /* maximum window shift */
142
143#define TCP_MAXBURST 4 /* maximum segments in a burst */
144
145#define TCP_MAXHLEN (0xf<<2) /* max length of header in bytes */
146#define TCP_MAXOLEN (TCP_MAXHLEN - sizeof(struct tcphdr))
147 /* max space left for options */
148#endif /* __BSD_VISIBLE */
149
150/*
151 * User-settable options (used with setsockopt).
152 */
153#define TCP_NODELAY 0x01 /* don't delay send to coalesce packets */
154#if __BSD_VISIBLE
155#define TCP_MAXSEG 0x02 /* set maximum segment size */
156#define TCP_NOPUSH 0x04 /* don't push last block of write */
157#define TCP_NOOPT 0x08 /* don't use TCP options */
158#define TCP_MD5SIG 0x10 /* use MD5 digests (RFC2385) */
159#define TCP_INFO 0x20 /* retrieve tcp_info structure */
160#define TCP_CONGESTION 0x40 /* get/set congestion control algorithm */
161
162#define TCP_CA_NAME_MAX 16 /* max congestion control name length */
163
164#define TCPI_OPT_TIMESTAMPS 0x01
165#define TCPI_OPT_SACK 0x02
166#define TCPI_OPT_WSCALE 0x04
167#define TCPI_OPT_ECN 0x08
168#define TCPI_OPT_TOE 0x10
169
170/*
171 * The TCP_INFO socket option comes from the Linux 2.6 TCP API, and permits
172 * the caller to query certain information about the state of a TCP
173 * connection. We provide an overlapping set of fields with the Linux
174 * implementation, but since this is a fixed size structure, room has been
175 * left for growth. In order to maximize potential future compatibility with
176 * the Linux API, the same variable names and order have been adopted, and
177 * padding left to make room for omitted fields in case they are added later.
178 *
179 * XXX: This is currently an unstable ABI/API, in that it is expected to
180 * change.
181 */
182struct tcp_info {
183 u_int8_t tcpi_state; /* TCP FSM state. */
184 u_int8_t __tcpi_ca_state;
185 u_int8_t __tcpi_retransmits;
186 u_int8_t __tcpi_probes;
187 u_int8_t __tcpi_backoff;
188 u_int8_t tcpi_options; /* Options enabled on conn. */
189 u_int8_t tcpi_snd_wscale:4, /* RFC1323 send shift value. */
190 tcpi_rcv_wscale:4; /* RFC1323 recv shift value. */
191
192 u_int32_t tcpi_rto; /* Retransmission timeout (usec). */
193 u_int32_t __tcpi_ato;
194 u_int32_t tcpi_snd_mss; /* Max segment size for send. */
195 u_int32_t tcpi_rcv_mss; /* Max segment size for receive. */
196
197 u_int32_t __tcpi_unacked;
198 u_int32_t __tcpi_sacked;
199 u_int32_t __tcpi_lost;
200 u_int32_t __tcpi_retrans;
201 u_int32_t __tcpi_fackets;
202
203 /* Times; measurements in usecs. */
204 u_int32_t __tcpi_last_data_sent;
205 u_int32_t __tcpi_last_ack_sent; /* Also unimpl. on Linux? */
206 u_int32_t tcpi_last_data_recv; /* Time since last recv data. */
207 u_int32_t __tcpi_last_ack_recv;
208
209 /* Metrics; variable units. */
210 u_int32_t __tcpi_pmtu;
211 u_int32_t __tcpi_rcv_ssthresh;
212 u_int32_t tcpi_rtt; /* Smoothed RTT in usecs. */
213 u_int32_t tcpi_rttvar; /* RTT variance in usecs. */
214 u_int32_t tcpi_snd_ssthresh; /* Slow start threshold. */
215 u_int32_t tcpi_snd_cwnd; /* Send congestion window. */
216 u_int32_t __tcpi_advmss;
217 u_int32_t __tcpi_reordering;
218
219 u_int32_t __tcpi_rcv_rtt;
220 u_int32_t tcpi_rcv_space; /* Advertised recv window. */
221
222 /* FreeBSD extensions to tcp_info. */
223 u_int32_t tcpi_snd_wnd; /* Advertised send window. */
224 u_int32_t tcpi_snd_bwnd; /* Bandwidth send window. */
225 u_int32_t tcpi_snd_nxt; /* Next egress seqno */
226 u_int32_t tcpi_rcv_nxt; /* Next ingress seqno */
227 u_int32_t tcpi_toe_tid; /* HWTID for TOE endpoints */
228
229 /* Padding to grow without breaking ABI. */
230 u_int32_t __tcpi_pad[29]; /* Padding. */
231};
232#endif
233
234#endif /* !_NETINET_TCP_H_ */
|