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 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)ip.h 8.2 (Berkeley) 6/1/94 34 */ 35 36 #ifndef netdissect_ip_h 37 #define netdissect_ip_h 38 39 /* 40 * Definitions for internet protocol version 4. 41 * Per RFC 791, September 1981. 42 */ 43 #define IPVERSION 4 44 45 /* 46 * Structure of an internet header, naked of options. 47 * 48 * We declare ip_len and ip_off to be short, rather than u_short 49 * pragmatically since otherwise unsigned comparisons can result 50 * against negative integers quite easily, and fail in subtle ways. 51 */ 52 struct ip { 53 nd_uint8_t ip_vhl; /* header length, version */ 54 #define IP_V(ip) ((GET_U_1((ip)->ip_vhl) & 0xf0) >> 4) 55 #define IP_HL(ip) (GET_U_1((ip)->ip_vhl) & 0x0f) 56 nd_uint8_t ip_tos; /* type of service */ 57 nd_uint16_t ip_len; /* total length */ 58 nd_uint16_t ip_id; /* identification */ 59 nd_uint16_t ip_off; /* fragment offset field */ 60 #define IP_DF 0x4000 /* don't fragment flag */ 61 #define IP_MF 0x2000 /* more fragments flag */ 62 #define IP_OFFMASK 0x1fff /* mask for fragmenting bits */ 63 nd_uint8_t ip_ttl; /* time to live */ 64 nd_uint8_t ip_p; /* protocol */ 65 nd_uint16_t ip_sum; /* checksum */ 66 nd_ipv4 ip_src,ip_dst; /* source and dest address */ 67 }; 68 69 #define IP_MAXPACKET 65535 /* maximum packet size */ 70 71 /* 72 * Definitions for IP type of service (ip_tos) 73 */ 74 #define IPTOS_LOWDELAY 0x10 75 #define IPTOS_THROUGHPUT 0x08 76 #define IPTOS_RELIABILITY 0x04 77 78 /* 79 * Definitions for IP precedence (also in ip_tos) (hopefully unused) 80 */ 81 #define IPTOS_PREC_NETCONTROL 0xe0 82 #define IPTOS_PREC_INTERNETCONTROL 0xc0 83 #define IPTOS_PREC_CRITIC_ECP 0xa0 84 #define IPTOS_PREC_FLASHOVERRIDE 0x80 85 #define IPTOS_PREC_FLASH 0x60 86 #define IPTOS_PREC_IMMEDIATE 0x40 87 #define IPTOS_PREC_PRIORITY 0x20 88 #define IPTOS_PREC_ROUTINE 0x00 89 90 /* 91 * Definitions for options. 92 */ 93 #define IPOPT_COPIED(o) ((o)&0x80) 94 #define IPOPT_CLASS(o) ((o)&0x60) 95 #define IPOPT_NUMBER(o) ((o)&0x1f) 96 97 #define IPOPT_CONTROL 0x00 98 #define IPOPT_RESERVED1 0x20 99 #define IPOPT_DEBMEAS 0x40 100 #define IPOPT_RESERVED2 0x60 101 102 #define IPOPT_EOL 0 /* end of option list */ 103 #define IPOPT_NOP 1 /* no operation */ 104 105 #define IPOPT_RR 7 /* record packet route */ 106 #define IPOPT_TS 68 /* timestamp */ 107 #define IPOPT_RFC1393 82 /* traceroute RFC 1393 */ 108 #define IPOPT_SECURITY 130 /* provide s,c,h,tcc */ 109 #define IPOPT_LSRR 131 /* loose source route */ 110 #define IPOPT_SATID 136 /* satnet id */ 111 #define IPOPT_SSRR 137 /* strict source route */ 112 #define IPOPT_RA 148 /* router-alert, rfc2113 */ 113 114 /* 115 * Offsets to fields in options other than EOL and NOP. 116 */ 117 #define IPOPT_OPTVAL 0 /* option ID */ 118 #define IPOPT_OLEN 1 /* option length */ 119 #define IPOPT_OFFSET 2 /* offset within option */ 120 #define IPOPT_MINOFF 4 /* min value of above */ 121 122 /* 123 * Time stamp option structure. 124 */ 125 struct ip_timestamp { 126 nd_uint8_t ipt_code; /* IPOPT_TS */ 127 nd_uint8_t ipt_len; /* size of structure (variable) */ 128 nd_uint8_t ipt_ptr; /* index of current entry */ 129 nd_uint8_t ipt_oflwflg; /* flags, overflow counter */ 130 #define IPTS_OFLW(ip) (((ipt)->ipt_oflwflg & 0xf0) >> 4) 131 #define IPTS_FLG(ip) ((ipt)->ipt_oflwflg & 0x0f) 132 union ipt_timestamp { 133 nd_uint32_t ipt_time[1]; 134 struct ipt_ta { 135 nd_ipv4 ipt_addr; 136 nd_uint32_t ipt_time; 137 } ipt_ta[1]; 138 } ipt_timestamp; 139 }; 140 141 /* flag bits for ipt_flg */ 142 #define IPOPT_TS_TSONLY 0 /* timestamps only */ 143 #define IPOPT_TS_TSANDADDR 1 /* timestamps and addresses */ 144 #define IPOPT_TS_PRESPEC 3 /* specified modules only */ 145 146 /* bits for security (not byte swapped) */ 147 #define IPOPT_SECUR_UNCLASS 0x0000 148 #define IPOPT_SECUR_CONFID 0xf135 149 #define IPOPT_SECUR_EFTO 0x789a 150 #define IPOPT_SECUR_MMMM 0xbc4d 151 #define IPOPT_SECUR_RESTR 0xaf13 152 #define IPOPT_SECUR_SECRET 0xd788 153 #define IPOPT_SECUR_TOPSECRET 0x6bc5 154 155 /* 156 * Internet implementation parameters. 157 */ 158 #define MAXTTL 255 /* maximum time to live (seconds) */ 159 #define IPDEFTTL 64 /* default ttl, from RFC 1340 */ 160 #define IPFRAGTTL 60 /* time to live for frags, slowhz */ 161 #define IPTTLDEC 1 /* subtracted when forwarding */ 162 163 #define IP_MSS 576 /* default maximum segment size */ 164 #endif /* netdissect_ip_h */ 165