1 /*- 2 * Copyright (c) 1982, 1986, 1993 3 * The Regents of the University of California. 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 4. Neither the name of the University nor the names of its contributors 15 * may be used to endorse or promote products derived from this software 16 * without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 * 30 * @(#)ip.h 8.2 (Berkeley) 6/1/94 31 * $FreeBSD$ 32 */ 33 34 #ifndef _NETINET_IP_H_ 35 #define _NETINET_IP_H_ 36 37 #include <sys/cdefs.h> 38 39 /* 40 * Definitions for internet protocol version 4. 41 * 42 * Per RFC 791, September 1981. 43 */ 44 #define IPVERSION 4 45 46 /* 47 * Structure of an internet header, naked of options. 48 */ 49 struct ip { 50 #if BYTE_ORDER == LITTLE_ENDIAN 51 u_int ip_hl:4, /* header length */ 52 ip_v:4; /* version */ 53 #endif 54 #if BYTE_ORDER == BIG_ENDIAN 55 u_int ip_v:4, /* version */ 56 ip_hl:4; /* header length */ 57 #endif 58 u_char ip_tos; /* type of service */ 59 u_short ip_len; /* total length */ 60 u_short ip_id; /* identification */ 61 u_short ip_off; /* fragment offset field */ 62 #define IP_RF 0x8000 /* reserved fragment flag */ 63 #define IP_DF 0x4000 /* dont fragment flag */ 64 #define IP_MF 0x2000 /* more fragments flag */ 65 #define IP_OFFMASK 0x1fff /* mask for fragmenting bits */ 66 u_char ip_ttl; /* time to live */ 67 u_char ip_p; /* protocol */ 68 u_short ip_sum; /* checksum */ 69 struct in_addr ip_src,ip_dst; /* source and dest address */ 70 } __packed __aligned(4); 71 72 #ifdef CTASSERT 73 CTASSERT(sizeof (struct ip) == 20); 74 #endif 75 76 #define IP_MAXPACKET 65535 /* maximum packet size */ 77 78 /* 79 * Definitions for IP type of service (ip_tos). 80 */ 81 #define IPTOS_LOWDELAY 0x10 82 #define IPTOS_THROUGHPUT 0x08 83 #define IPTOS_RELIABILITY 0x04 84 #define IPTOS_MINCOST 0x02 85 86 /* 87 * Definitions for IP precedence (also in ip_tos) (hopefully unused). 88 */ 89 #define IPTOS_PREC_NETCONTROL 0xe0 90 #define IPTOS_PREC_INTERNETCONTROL 0xc0 91 #define IPTOS_PREC_CRITIC_ECP 0xa0 92 #define IPTOS_PREC_FLASHOVERRIDE 0x80 93 #define IPTOS_PREC_FLASH 0x60 94 #define IPTOS_PREC_IMMEDIATE 0x40 95 #define IPTOS_PREC_PRIORITY 0x20 96 #define IPTOS_PREC_ROUTINE 0x00 97 98 /* 99 * ECN (Explicit Congestion Notification) codepoints in RFC3168 mapped to the 100 * lower 2 bits of the TOS field. 101 */ 102 #define IPTOS_ECN_NOTECT 0x00 /* not-ECT */ 103 #define IPTOS_ECN_ECT1 0x01 /* ECN-capable transport (1) */ 104 #define IPTOS_ECN_ECT0 0x02 /* ECN-capable transport (0) */ 105 #define IPTOS_ECN_CE 0x03 /* congestion experienced */ 106 #define IPTOS_ECN_MASK 0x03 /* ECN field mask */ 107 108 /* 109 * Definitions for options. 110 */ 111 #define IPOPT_COPIED(o) ((o)&0x80) 112 #define IPOPT_CLASS(o) ((o)&0x60) 113 #define IPOPT_NUMBER(o) ((o)&0x1f) 114 115 #define IPOPT_CONTROL 0x00 116 #define IPOPT_RESERVED1 0x20 117 #define IPOPT_DEBMEAS 0x40 118 #define IPOPT_RESERVED2 0x60 119 120 #define IPOPT_EOL 0 /* end of option list */ 121 #define IPOPT_NOP 1 /* no operation */ 122 123 #define IPOPT_RR 7 /* record packet route */ 124 #define IPOPT_TS 68 /* timestamp */ 125 #define IPOPT_SECURITY 130 /* provide s,c,h,tcc */ 126 #define IPOPT_LSRR 131 /* loose source route */ 127 #define IPOPT_ESO 133 /* extended security */ 128 #define IPOPT_CIPSO 134 /* commerical security */ 129 #define IPOPT_SATID 136 /* satnet id */ 130 #define IPOPT_SSRR 137 /* strict source route */ 131 #define IPOPT_RA 148 /* router alert */ 132 133 /* 134 * Offsets to fields in options other than EOL and NOP. 135 */ 136 #define IPOPT_OPTVAL 0 /* option ID */ 137 #define IPOPT_OLEN 1 /* option length */ 138 #define IPOPT_OFFSET 2 /* offset within option */ 139 #define IPOPT_MINOFF 4 /* min value of above */ 140 141 /* 142 * Time stamp option structure. 143 */ 144 struct ip_timestamp { 145 u_char ipt_code; /* IPOPT_TS */ 146 u_char ipt_len; /* size of structure (variable) */ 147 u_char ipt_ptr; /* index of current entry */ 148 #if BYTE_ORDER == LITTLE_ENDIAN 149 u_int ipt_flg:4, /* flags, see below */ 150 ipt_oflw:4; /* overflow counter */ 151 #endif 152 #if BYTE_ORDER == BIG_ENDIAN 153 u_int ipt_oflw:4, /* overflow counter */ 154 ipt_flg:4; /* flags, see below */ 155 #endif 156 union ipt_timestamp { 157 n_long ipt_time[1]; 158 struct ipt_ta { 159 struct in_addr ipt_addr; 160 n_long ipt_time; 161 } ipt_ta[1]; 162 } ipt_timestamp; 163 }; 164 165 /* Flag bits for ipt_flg. */ 166 #define IPOPT_TS_TSONLY 0 /* timestamps only */ 167 #define IPOPT_TS_TSANDADDR 1 /* timestamps and addresses */ 168 #define IPOPT_TS_PRESPEC 3 /* specified modules only */ 169 170 /* Bits for security (not byte swapped). */ 171 #define IPOPT_SECUR_UNCLASS 0x0000 172 #define IPOPT_SECUR_CONFID 0xf135 173 #define IPOPT_SECUR_EFTO 0x789a 174 #define IPOPT_SECUR_MMMM 0xbc4d 175 #define IPOPT_SECUR_RESTR 0xaf13 176 #define IPOPT_SECUR_SECRET 0xd788 177 #define IPOPT_SECUR_TOPSECRET 0x6bc5 178 179 /* 180 * Internet implementation parameters. 181 */ 182 #define MAXTTL 255 /* maximum time to live (seconds) */ 183 #define IPDEFTTL 64 /* default ttl, from RFC 1340 */ 184 #define IPFRAGTTL 60 /* time to live for frags, slowhz */ 185 #define IPTTLDEC 1 /* subtracted when forwarding */ 186 #define IP_MSS 576 /* default maximum segment size */ 187 188 /* 189 * This is the real IPv4 pseudo header, used for computing the TCP and UDP 190 * checksums. For the Internet checksum, struct ipovly can be used instead. 191 * For stronger checksums, the real thing must be used. 192 */ 193 struct ippseudo { 194 struct in_addr ippseudo_src; /* source internet address */ 195 struct in_addr ippseudo_dst; /* destination internet address */ 196 u_char ippseudo_pad; /* pad, must be zero */ 197 u_char ippseudo_p; /* protocol */ 198 u_short ippseudo_len; /* protocol length */ 199 }; 200 #endif 201