| /*- |
| * 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 |
| * $FreeBSD$ |
| */ |
| |
| /* |
| * samkumar: In one instance (in struct tcphdr), where there are Big Endian |
| * and Little Endian alternatives for ordering two fields, I hardcoded the |
| * Little Endian alternative. If ever we port this to a Big Endian platform, |
| * we should look at that very closely, and consider rewriting it. |
| */ |
| |
| #ifndef TCPLP_NETINET_TCP_H_ |
| #define TCPLP_NETINET_TCP_H_ |
| |
| #include <stdint.h> |
| #include <stdio.h> |
| |
| #define KASSERT(COND, MSG) if (!(COND)) tcplp_sys_panic MSG |
| |
| typedef uint32_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 { |
| uint16_t th_sport; /* source port */ |
| uint16_t th_dport; /* destination port */ |
| tcp_seq th_seq; /* sequence number */ |
| tcp_seq th_ack; /* acknowledgement number */ |
| |
| /* |
| * samkumar: The original FreeBSD code used bit fields for the offset and |
| * unused bits, within this byte. I've rewritten it to avoid the use of |
| * bit fields, so that the code is more portable. The original code, which |
| * defined the order of bit fields based on the platform's endianness, is |
| * included below, commented out using "#if 0". |
| */ |
| uint8_t th_off_x2; /* data offset and unused bits */ |
| #define TH_OFF_SHIFT 4 |
| |
| #if 0 |
| #if BYTE_ORDER == LITTLE_ENDIAN |
| uint8_t th_x2:4, /* (unused) */ |
| th_off:4; /* data offset */ |
| #endif |
| #if BYTE_ORDER == BIG_ENDIAN |
| uint8_t th_off:4, /* data offset */ |
| th_x2:4; /* (unused) */ |
| #endif |
| #endif |
| |
| uint8_t 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" |
| |
| uint16_t th_win; /* window */ |
| uint16_t th_sum; /* checksum */ |
| uint16_t 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 */ |
| |
| /* |
| * 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 */ |
| #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 */ |
| #define TCP_PCAP_OUT 2048 /* number of output packets to keep */ |
| #define TCP_PCAP_IN 4096 /* number of input packets to keep */ |
| |
| /* 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 |
| |
| #endif /* !_NETINET_TCP_H_ */ |
