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. 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 * @(#)ip.h 8.2 (Berkeley) 6/1/94 30 */ 31 32 #ifndef netdissect_ip_h 33 #define netdissect_ip_h 34 35 /* 36 * Definitions for internet protocol version 4. 37 * Per RFC 791, September 1981. 38 */ 39 #define IPVERSION 4 40 41 /* 42 * Structure of an internet header, naked of options. 43 * 44 * We declare ip_len and ip_off to be short, rather than u_short 45 * pragmatically since otherwise unsigned comparisons can result 46 * against negative integers quite easily, and fail in subtle ways. 47 */ 48 struct ip { 49 nd_uint8_t ip_vhl; /* header length, version */ 50 #define IP_V(ip) ((GET_U_1((ip)->ip_vhl) & 0xf0) >> 4) 51 #define IP_HL(ip) (GET_U_1((ip)->ip_vhl) & 0x0f) 52 nd_uint8_t ip_tos; /* type of service */ 53 nd_uint16_t ip_len; /* total length */ 54 nd_uint16_t ip_id; /* identification */ 55 nd_uint16_t ip_off; /* fragment offset field */ 56 #define IP_DF 0x4000 /* don't fragment flag */ 57 #define IP_MF 0x2000 /* more fragments flag */ 58 #define IP_OFFMASK 0x1fff /* mask for fragmenting bits */ 59 nd_uint8_t ip_ttl; /* time to live */ 60 nd_uint8_t ip_p; /* protocol */ 61 nd_uint16_t ip_sum; /* checksum */ 62 nd_ipv4 ip_src,ip_dst; /* source and dest address */ 63 }; 64 65 #define IP_MAXPACKET 65535 /* maximum packet size */ 66 67 /* 68 * Definitions for IP type of service (ip_tos) 69 */ 70 #define IPTOS_LOWDELAY 0x10 71 #define IPTOS_THROUGHPUT 0x08 72 #define IPTOS_RELIABILITY 0x04 73 74 /* 75 * Definitions for IP precedence (also in ip_tos) (hopefully unused) 76 */ 77 #define IPTOS_PREC_NETCONTROL 0xe0 78 #define IPTOS_PREC_INTERNETCONTROL 0xc0 79 #define IPTOS_PREC_CRITIC_ECP 0xa0 80 #define IPTOS_PREC_FLASHOVERRIDE 0x80 81 #define IPTOS_PREC_FLASH 0x60 82 #define IPTOS_PREC_IMMEDIATE 0x40 83 #define IPTOS_PREC_PRIORITY 0x20 84 #define IPTOS_PREC_ROUTINE 0x00 85 86 /* 87 * Definitions for options. 88 */ 89 #define IPOPT_COPIED(o) ((o)&0x80) 90 #define IPOPT_CLASS(o) ((o)&0x60) 91 #define IPOPT_NUMBER(o) ((o)&0x1f) 92 93 #define IPOPT_CONTROL 0x00 94 #define IPOPT_RESERVED1 0x20 95 #define IPOPT_DEBMEAS 0x40 96 #define IPOPT_RESERVED2 0x60 97 98 #define IPOPT_EOL 0 /* end of option list */ 99 #define IPOPT_NOP 1 /* no operation */ 100 101 #define IPOPT_RR 7 /* record packet route */ 102 #define IPOPT_TS 68 /* timestamp */ 103 #define IPOPT_RFC1393 82 /* traceroute RFC 1393 */ 104 #define IPOPT_SECURITY 130 /* provide s,c,h,tcc */ 105 #define IPOPT_LSRR 131 /* loose source route */ 106 #define IPOPT_SSRR 137 /* strict source route */ 107 #define IPOPT_RA 148 /* router-alert, rfc2113 */ 108 109 /* 110 * Offsets to fields in options other than EOL and NOP. 111 */ 112 #define IPOPT_OPTVAL 0 /* option ID */ 113 #define IPOPT_OLEN 1 /* option length */ 114 #define IPOPT_OFFSET 2 /* offset within option */ 115 #define IPOPT_MINOFF 4 /* min value of above */ 116 117 /* 118 * Time stamp option structure. 119 */ 120 struct ip_timestamp { 121 nd_uint8_t ipt_code; /* IPOPT_TS */ 122 nd_uint8_t ipt_len; /* size of structure (variable) */ 123 nd_uint8_t ipt_ptr; /* index of current entry */ 124 nd_uint8_t ipt_oflwflg; /* flags, overflow counter */ 125 #define IPTS_OFLW(ip) (((ipt)->ipt_oflwflg & 0xf0) >> 4) 126 #define IPTS_FLG(ip) ((ipt)->ipt_oflwflg & 0x0f) 127 union ipt_timestamp { 128 nd_uint32_t ipt_time[1]; 129 struct ipt_ta { 130 nd_ipv4 ipt_addr; 131 nd_uint32_t ipt_time; 132 } ipt_ta[1]; 133 } ipt_timestamp; 134 }; 135 136 /* flag bits for ipt_flg */ 137 #define IPOPT_TS_TSONLY 0 /* timestamps only */ 138 #define IPOPT_TS_TSANDADDR 1 /* timestamps and addresses */ 139 #define IPOPT_TS_PRESPEC 3 /* specified modules only */ 140 141 /* bits for security (not byte swapped) */ 142 #define IPOPT_SECUR_UNCLASS 0x0000 143 #define IPOPT_SECUR_CONFID 0xf135 144 #define IPOPT_SECUR_EFTO 0x789a 145 #define IPOPT_SECUR_MMMM 0xbc4d 146 #define IPOPT_SECUR_RESTR 0xaf13 147 #define IPOPT_SECUR_SECRET 0xd788 148 #define IPOPT_SECUR_TOPSECRET 0x6bc5 149 150 /* 151 * Internet implementation parameters. 152 */ 153 #define MAXTTL 255 /* maximum time to live (seconds) */ 154 #define IPDEFTTL 64 /* default ttl, from RFC 1340 */ 155 #define IPFRAGTTL 60 /* time to live for frags, slowhz */ 156 #define IPTTLDEC 1 /* subtracted when forwarding */ 157 158 #define IP_MSS 576 /* default maximum segment size */ 159 #endif /* netdissect_ip_h */ 160
Indexes created Tue Feb 24 01:34:59 UTC 2026