mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-23 11:18:54 +00:00
248 lines
9.0 KiB
C
248 lines
9.0 KiB
C
/*-
|
|
* Copyright (c) 1982, 1986, 1993
|
|
* The Regents of the University of California. All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. 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.
|
|
* 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
|
|
*
|
|
* @(#)tcp.h 8.1 (Berkeley) 6/10/93
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#ifndef _NETINET_TCP_H_
|
|
#define _NETINET_TCP_H_
|
|
|
|
#include <sys/cdefs.h>
|
|
#include <sys/types.h>
|
|
|
|
#if __BSD_VISIBLE
|
|
|
|
typedef u_int32_t tcp_seq;
|
|
|
|
#define tcp6_seq tcp_seq /* for KAME src sync over BSD*'s */
|
|
#define tcp6hdr tcphdr /* for KAME src sync over BSD*'s */
|
|
|
|
/*
|
|
* TCP header.
|
|
* Per RFC 793, September, 1981.
|
|
*/
|
|
struct tcphdr {
|
|
u_short th_sport; /* source port */
|
|
u_short th_dport; /* destination port */
|
|
tcp_seq th_seq; /* sequence number */
|
|
tcp_seq th_ack; /* acknowledgement number */
|
|
#if BYTE_ORDER == LITTLE_ENDIAN
|
|
u_char th_x2:4, /* (unused) */
|
|
th_off:4; /* data offset */
|
|
#endif
|
|
#if BYTE_ORDER == BIG_ENDIAN
|
|
u_char th_off:4, /* data offset */
|
|
th_x2:4; /* (unused) */
|
|
#endif
|
|
u_char th_flags;
|
|
#define TH_FIN 0x01
|
|
#define TH_SYN 0x02
|
|
#define TH_RST 0x04
|
|
#define TH_PUSH 0x08
|
|
#define TH_ACK 0x10
|
|
#define TH_URG 0x20
|
|
#define TH_ECE 0x40
|
|
#define TH_CWR 0x80
|
|
#define TH_FLAGS (TH_FIN|TH_SYN|TH_RST|TH_PUSH|TH_ACK|TH_URG|TH_ECE|TH_CWR)
|
|
#define PRINT_TH_FLAGS "\20\1FIN\2SYN\3RST\4PUSH\5ACK\6URG\7ECE\10CWR"
|
|
|
|
u_short th_win; /* window */
|
|
u_short th_sum; /* checksum */
|
|
u_short th_urp; /* urgent pointer */
|
|
};
|
|
|
|
#define TCPOPT_EOL 0
|
|
#define TCPOLEN_EOL 1
|
|
#define TCPOPT_PAD 0 /* padding after EOL */
|
|
#define TCPOLEN_PAD 1
|
|
#define TCPOPT_NOP 1
|
|
#define TCPOLEN_NOP 1
|
|
#define TCPOPT_MAXSEG 2
|
|
#define TCPOLEN_MAXSEG 4
|
|
#define TCPOPT_WINDOW 3
|
|
#define TCPOLEN_WINDOW 3
|
|
#define TCPOPT_SACK_PERMITTED 4
|
|
#define TCPOLEN_SACK_PERMITTED 2
|
|
#define TCPOPT_SACK 5
|
|
#define TCPOLEN_SACKHDR 2
|
|
#define TCPOLEN_SACK 8 /* 2*sizeof(tcp_seq) */
|
|
#define TCPOPT_TIMESTAMP 8
|
|
#define TCPOLEN_TIMESTAMP 10
|
|
#define TCPOLEN_TSTAMP_APPA (TCPOLEN_TIMESTAMP+2) /* appendix A */
|
|
#define TCPOPT_SIGNATURE 19 /* Keyed MD5: RFC 2385 */
|
|
#define TCPOLEN_SIGNATURE 18
|
|
|
|
/* Miscellaneous constants */
|
|
#define MAX_SACK_BLKS 6 /* Max # SACK blocks stored at receiver side */
|
|
#define TCP_MAX_SACK 4 /* MAX # SACKs sent in any segment */
|
|
|
|
|
|
/*
|
|
* The default maximum segment size (MSS) to be used for new TCP connections
|
|
* when path MTU discovery is not enabled.
|
|
*
|
|
* RFC879 derives the default MSS from the largest datagram size hosts are
|
|
* minimally required to handle directly or through IP reassembly minus the
|
|
* size of the IP and TCP header. With IPv6 the minimum MTU is specified
|
|
* in RFC2460.
|
|
*
|
|
* For IPv4 the MSS is 576 - sizeof(struct tcpiphdr)
|
|
* For IPv6 the MSS is IPV6_MMTU - sizeof(struct ip6_hdr) - sizeof(struct tcphdr)
|
|
*
|
|
* We use explicit numerical definition here to avoid header pollution.
|
|
*/
|
|
#define TCP_MSS 536
|
|
#define TCP6_MSS 1220
|
|
|
|
/*
|
|
* Limit the lowest MSS we accept for path MTU discovery and the TCP SYN MSS
|
|
* option. Allowing low values of MSS can consume significant resources and
|
|
* be used to mount a resource exhaustion attack.
|
|
* Connections requesting lower MSS values will be rounded up to this value
|
|
* and the IP_DF flag will be cleared to allow fragmentation along the path.
|
|
*
|
|
* See tcp_subr.c tcp_minmss SYSCTL declaration for more comments. Setting
|
|
* it to "0" disables the minmss check.
|
|
*
|
|
* The default value is fine for TCP across the Internet's smallest official
|
|
* link MTU (256 bytes for AX.25 packet radio). However, a connection is very
|
|
* unlikely to come across such low MTU interfaces these days (anno domini 2003).
|
|
*/
|
|
#define TCP_MINMSS 216
|
|
|
|
#define TCP_MAXWIN 65535 /* largest value for (unscaled) window */
|
|
#define TTCP_CLIENT_SND_WND 4096 /* dflt send window for T/TCP client */
|
|
|
|
#define TCP_MAX_WINSHIFT 14 /* maximum window shift */
|
|
|
|
#define TCP_MAXBURST 4 /* maximum segments in a burst */
|
|
|
|
#define TCP_MAXHLEN (0xf<<2) /* max length of header in bytes */
|
|
#define TCP_MAXOLEN (TCP_MAXHLEN - sizeof(struct tcphdr))
|
|
/* max space left for options */
|
|
#endif /* __BSD_VISIBLE */
|
|
|
|
/*
|
|
* User-settable options (used with setsockopt). These are discrete
|
|
* values and are not masked together. Some values appear to be
|
|
* bitmasks for historical reasons.
|
|
*/
|
|
#define TCP_NODELAY 1 /* don't delay send to coalesce packets */
|
|
#if __BSD_VISIBLE
|
|
#define TCP_MAXSEG 2 /* set maximum segment size */
|
|
#define TCP_NOPUSH 4 /* don't push last block of write */
|
|
#define TCP_NOOPT 8 /* don't use TCP options */
|
|
#define TCP_MD5SIG 16 /* use MD5 digests (RFC2385) */
|
|
#define TCP_INFO 32 /* retrieve tcp_info structure */
|
|
#define TCP_CONGESTION 64 /* get/set congestion control algorithm */
|
|
#define TCP_KEEPINIT 128 /* N, time to establish connection */
|
|
#define TCP_KEEPIDLE 256 /* L,N,X start keeplives after this period */
|
|
#define TCP_KEEPINTVL 512 /* L,N interval between keepalives */
|
|
#define TCP_KEEPCNT 1024 /* L,N number of keepalives before close */
|
|
|
|
/* Start of reserved space for third-party user-settable options. */
|
|
#define TCP_VENDOR SO_VENDOR
|
|
|
|
#define TCP_CA_NAME_MAX 16 /* max congestion control name length */
|
|
|
|
#define TCPI_OPT_TIMESTAMPS 0x01
|
|
#define TCPI_OPT_SACK 0x02
|
|
#define TCPI_OPT_WSCALE 0x04
|
|
#define TCPI_OPT_ECN 0x08
|
|
#define TCPI_OPT_TOE 0x10
|
|
|
|
/*
|
|
* The TCP_INFO socket option comes from the Linux 2.6 TCP API, and permits
|
|
* the caller to query certain information about the state of a TCP
|
|
* connection. We provide an overlapping set of fields with the Linux
|
|
* implementation, but since this is a fixed size structure, room has been
|
|
* left for growth. In order to maximize potential future compatibility with
|
|
* the Linux API, the same variable names and order have been adopted, and
|
|
* padding left to make room for omitted fields in case they are added later.
|
|
*
|
|
* XXX: This is currently an unstable ABI/API, in that it is expected to
|
|
* change.
|
|
*/
|
|
struct tcp_info {
|
|
u_int8_t tcpi_state; /* TCP FSM state. */
|
|
u_int8_t __tcpi_ca_state;
|
|
u_int8_t __tcpi_retransmits;
|
|
u_int8_t __tcpi_probes;
|
|
u_int8_t __tcpi_backoff;
|
|
u_int8_t tcpi_options; /* Options enabled on conn. */
|
|
u_int8_t tcpi_snd_wscale:4, /* RFC1323 send shift value. */
|
|
tcpi_rcv_wscale:4; /* RFC1323 recv shift value. */
|
|
|
|
u_int32_t tcpi_rto; /* Retransmission timeout (usec). */
|
|
u_int32_t __tcpi_ato;
|
|
u_int32_t tcpi_snd_mss; /* Max segment size for send. */
|
|
u_int32_t tcpi_rcv_mss; /* Max segment size for receive. */
|
|
|
|
u_int32_t __tcpi_unacked;
|
|
u_int32_t __tcpi_sacked;
|
|
u_int32_t __tcpi_lost;
|
|
u_int32_t __tcpi_retrans;
|
|
u_int32_t __tcpi_fackets;
|
|
|
|
/* Times; measurements in usecs. */
|
|
u_int32_t __tcpi_last_data_sent;
|
|
u_int32_t __tcpi_last_ack_sent; /* Also unimpl. on Linux? */
|
|
u_int32_t tcpi_last_data_recv; /* Time since last recv data. */
|
|
u_int32_t __tcpi_last_ack_recv;
|
|
|
|
/* Metrics; variable units. */
|
|
u_int32_t __tcpi_pmtu;
|
|
u_int32_t __tcpi_rcv_ssthresh;
|
|
u_int32_t tcpi_rtt; /* Smoothed RTT in usecs. */
|
|
u_int32_t tcpi_rttvar; /* RTT variance in usecs. */
|
|
u_int32_t tcpi_snd_ssthresh; /* Slow start threshold. */
|
|
u_int32_t tcpi_snd_cwnd; /* Send congestion window. */
|
|
u_int32_t __tcpi_advmss;
|
|
u_int32_t __tcpi_reordering;
|
|
|
|
u_int32_t __tcpi_rcv_rtt;
|
|
u_int32_t tcpi_rcv_space; /* Advertised recv window. */
|
|
|
|
/* FreeBSD extensions to tcp_info. */
|
|
u_int32_t tcpi_snd_wnd; /* Advertised send window. */
|
|
u_int32_t tcpi_snd_bwnd; /* No longer used. */
|
|
u_int32_t tcpi_snd_nxt; /* Next egress seqno */
|
|
u_int32_t tcpi_rcv_nxt; /* Next ingress seqno */
|
|
u_int32_t tcpi_toe_tid; /* HWTID for TOE endpoints */
|
|
u_int32_t tcpi_snd_rexmitpack; /* Retransmitted packets */
|
|
u_int32_t tcpi_rcv_ooopack; /* Out-of-order packets */
|
|
u_int32_t tcpi_snd_zerowin; /* Zero-sized windows sent */
|
|
|
|
/* Padding to grow without breaking ABI. */
|
|
u_int32_t __tcpi_pad[26]; /* Padding. */
|
|
};
|
|
#endif
|
|
|
|
#endif /* !_NETINET_TCP_H_ */
|