1/* Copyright (C) 1991-2026 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18#ifndef __NETINET_IP_ICMP_H
19#define __NETINET_IP_ICMP_H 1
20
21#include <sys/types.h>
22#include <stdint.h>
23
24__BEGIN_DECLS
25
26struct icmphdr
27{
28 uint8_t type; /* message type */
29 uint8_t code; /* type sub-code */
30 uint16_t checksum;
31 union
32 {
33 struct
34 {
35 uint16_t id;
36 uint16_t sequence;
37 } echo; /* echo datagram */
38 uint32_t gateway; /* gateway address */
39 struct
40 {
41 uint16_t __glibc_reserved;
42 uint16_t mtu;
43 } frag; /* path mtu discovery */
44 } un;
45};
46
47#define ICMP_ECHOREPLY 0 /* Echo Reply */
48#define ICMP_DEST_UNREACH 3 /* Destination Unreachable */
49#define ICMP_SOURCE_QUENCH 4 /* Source Quench */
50#define ICMP_REDIRECT 5 /* Redirect (change route) */
51#define ICMP_ECHO 8 /* Echo Request */
52#define ICMP_TIME_EXCEEDED 11 /* Time Exceeded */
53#define ICMP_PARAMETERPROB 12 /* Parameter Problem */
54#define ICMP_TIMESTAMP 13 /* Timestamp Request */
55#define ICMP_TIMESTAMPREPLY 14 /* Timestamp Reply */
56#define ICMP_INFO_REQUEST 15 /* Information Request */
57#define ICMP_INFO_REPLY 16 /* Information Reply */
58#define ICMP_ADDRESS 17 /* Address Mask Request */
59#define ICMP_ADDRESSREPLY 18 /* Address Mask Reply */
60#define NR_ICMP_TYPES 18
61
62
63/* Codes for UNREACH. */
64#define ICMP_NET_UNREACH 0 /* Network Unreachable */
65#define ICMP_HOST_UNREACH 1 /* Host Unreachable */
66#define ICMP_PROT_UNREACH 2 /* Protocol Unreachable */
67#define ICMP_PORT_UNREACH 3 /* Port Unreachable */
68#define ICMP_FRAG_NEEDED 4 /* Fragmentation Needed/DF set */
69#define ICMP_SR_FAILED 5 /* Source Route failed */
70#define ICMP_NET_UNKNOWN 6
71#define ICMP_HOST_UNKNOWN 7
72#define ICMP_HOST_ISOLATED 8
73#define ICMP_NET_ANO 9
74#define ICMP_HOST_ANO 10
75#define ICMP_NET_UNR_TOS 11
76#define ICMP_HOST_UNR_TOS 12
77#define ICMP_PKT_FILTERED 13 /* Packet filtered */
78#define ICMP_PREC_VIOLATION 14 /* Precedence violation */
79#define ICMP_PREC_CUTOFF 15 /* Precedence cut off */
80#define NR_ICMP_UNREACH 15 /* instead of hardcoding immediate value */
81
82/* Codes for REDIRECT. */
83#define ICMP_REDIR_NET 0 /* Redirect Net */
84#define ICMP_REDIR_HOST 1 /* Redirect Host */
85#define ICMP_REDIR_NETTOS 2 /* Redirect Net for TOS */
86#define ICMP_REDIR_HOSTTOS 3 /* Redirect Host for TOS */
87
88/* Codes for TIME_EXCEEDED. */
89#define ICMP_EXC_TTL 0 /* TTL count exceeded */
90#define ICMP_EXC_FRAGTIME 1 /* Fragment Reass time exceeded */
91
92/* Codes for ICMP_EXT_ECHO (PROBE) */
93#define ICMP_EXT_ECHO 42
94#define ICMP_EXT_ECHOREPLY 43
95#define ICMP_EXT_CODE_MAL_QUERY 1 /* Malformed Query */
96#define ICMP_EXT_CODE_NO_IF 2 /* No such Interface */
97#define ICMP_EXT_CODE_NO_TABLE_ENT 3 /* No table entry */
98#define ICMP_EXT_CODE_MULT_IFS 4 /* Multiple Interfaces Satisfy Query */
99
100/* Constants for EXT_ECHO (PROBE) */
101#define ICMP_EXT_ECHOREPLY_ACTIVE (1 << 2)/* active bit in reply */
102#define ICMP_EXT_ECHOREPLY_IPV4 (1 << 1)/* ipv4 bit in reply */
103#define ICMP_EXT_ECHOREPLY_IPV6 1 /* ipv6 bit in reply */
104#define ICMP_EXT_ECHO_CTYPE_NAME 1
105#define ICMP_EXT_ECHO_CTYPE_INDEX 2
106#define ICMP_EXT_ECHO_CTYPE_ADDR 3
107#define ICMP_AFI_IP 1 /* Address Family Identifier for IPV4 */
108#define ICMP_AFI_IP6 2 /* Address Family Identifier for IPV6 */
109
110
111#ifdef __USE_MISC
112/*
113 * Copyright (c) 1982, 1986, 1993
114 * The Regents of the University of California. All rights reserved.
115 *
116 * Redistribution and use in source and binary forms, with or without
117 * modification, are permitted provided that the following conditions
118 * are met:
119 * 1. Redistributions of source code must retain the above copyright
120 * notice, this list of conditions and the following disclaimer.
121 * 2. Redistributions in binary form must reproduce the above copyright
122 * notice, this list of conditions and the following disclaimer in the
123 * documentation and/or other materials provided with the distribution.
124 * 4. Neither the name of the University nor the names of its contributors
125 * may be used to endorse or promote products derived from this software
126 * without specific prior written permission.
127 *
128 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
129 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
130 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
131 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
132 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
133 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
134 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
135 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
136 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
137 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
138 * SUCH DAMAGE.
139 *
140 * @(#)ip_icmp.h 8.1 (Berkeley) 6/10/93
141 */
142
143#include <netinet/in.h>
144#include <netinet/ip.h>
145
146/*
147 * Internal of an ICMP Router Advertisement
148 */
149struct icmp_ra_addr
150{
151 uint32_t ira_addr;
152 uint32_t ira_preference;
153};
154
155struct icmp
156{
157 uint8_t icmp_type; /* type of message, see below */
158 uint8_t icmp_code; /* type sub code */
159 uint16_t icmp_cksum; /* ones complement checksum of struct */
160 union
161 {
162 unsigned char ih_pptr; /* ICMP_PARAMPROB */
163 struct in_addr ih_gwaddr; /* gateway address */
164 struct ih_idseq /* echo datagram */
165 {
166 uint16_t icd_id;
167 uint16_t icd_seq;
168 } ih_idseq;
169 uint32_t ih_void;
170
171 /* ICMP_UNREACH_NEEDFRAG -- Path MTU Discovery (RFC1191) */
172 struct ih_pmtu
173 {
174 uint16_t ipm_void;
175 uint16_t ipm_nextmtu;
176 } ih_pmtu;
177
178 struct ih_rtradv
179 {
180 uint8_t irt_num_addrs;
181 uint8_t irt_wpa;
182 uint16_t irt_lifetime;
183 } ih_rtradv;
184 } icmp_hun;
185#define icmp_pptr icmp_hun.ih_pptr
186#define icmp_gwaddr icmp_hun.ih_gwaddr
187#define icmp_id icmp_hun.ih_idseq.icd_id
188#define icmp_seq icmp_hun.ih_idseq.icd_seq
189#define icmp_void icmp_hun.ih_void
190#define icmp_pmvoid icmp_hun.ih_pmtu.ipm_void
191#define icmp_nextmtu icmp_hun.ih_pmtu.ipm_nextmtu
192#define icmp_num_addrs icmp_hun.ih_rtradv.irt_num_addrs
193#define icmp_wpa icmp_hun.ih_rtradv.irt_wpa
194#define icmp_lifetime icmp_hun.ih_rtradv.irt_lifetime
195 union
196 {
197 struct
198 {
199 uint32_t its_otime;
200 uint32_t its_rtime;
201 uint32_t its_ttime;
202 } id_ts;
203 struct
204 {
205 struct ip idi_ip;
206 /* options and then 64 bits of data */
207 } id_ip;
208 struct icmp_ra_addr id_radv;
209 uint32_t id_mask;
210 uint8_t id_data[1];
211 } icmp_dun;
212#define icmp_otime icmp_dun.id_ts.its_otime
213#define icmp_rtime icmp_dun.id_ts.its_rtime
214#define icmp_ttime icmp_dun.id_ts.its_ttime
215#define icmp_ip icmp_dun.id_ip.idi_ip
216#define icmp_radv icmp_dun.id_radv
217#define icmp_mask icmp_dun.id_mask
218#define icmp_data icmp_dun.id_data
219};
220
221/*
222 * Lower bounds on packet lengths for various types.
223 * For the error advice packets must first insure that the
224 * packet is large enough to contain the returned ip header.
225 * Only then can we do the check to see if 64 bits of packet
226 * data have been returned, since we need to check the returned
227 * ip header length.
228 */
229#define ICMP_MINLEN 8 /* abs minimum */
230#define ICMP_TSLEN (8 + 3 * sizeof (n_time)) /* timestamp */
231#define ICMP_MASKLEN 12 /* address mask */
232#define ICMP_ADVLENMIN (8 + sizeof (struct ip) + 8) /* min */
233#ifndef _IP_VHL
234#define ICMP_ADVLEN(p) (8 + ((p)->icmp_ip.ip_hl << 2) + 8)
235 /* N.B.: must separately check that ip_hl >= 5 */
236#else
237#define ICMP_ADVLEN(p) (8 + (IP_VHL_HL((p)->icmp_ip.ip_vhl) << 2) + 8)
238 /* N.B.: must separately check that header length >= 5 */
239#endif
240
241/* Definition of type and code fields. */
242/* defined above: ICMP_ECHOREPLY, ICMP_REDIRECT, ICMP_ECHO */
243#define ICMP_UNREACH 3 /* dest unreachable, codes: */
244#define ICMP_SOURCEQUENCH 4 /* packet lost, slow down */
245#define ICMP_ROUTERADVERT 9 /* router advertisement */
246#define ICMP_ROUTERSOLICIT 10 /* router solicitation */
247#define ICMP_TIMXCEED 11 /* time exceeded, code: */
248#define ICMP_PARAMPROB 12 /* ip header bad */
249#define ICMP_TSTAMP 13 /* timestamp request */
250#define ICMP_TSTAMPREPLY 14 /* timestamp reply */
251#define ICMP_IREQ 15 /* information request */
252#define ICMP_IREQREPLY 16 /* information reply */
253#define ICMP_MASKREQ 17 /* address mask request */
254#define ICMP_MASKREPLY 18 /* address mask reply */
255
256#define ICMP_MAXTYPE 18
257
258/* UNREACH codes */
259#define ICMP_UNREACH_NET 0 /* bad net */
260#define ICMP_UNREACH_HOST 1 /* bad host */
261#define ICMP_UNREACH_PROTOCOL 2 /* bad protocol */
262#define ICMP_UNREACH_PORT 3 /* bad port */
263#define ICMP_UNREACH_NEEDFRAG 4 /* IP_DF caused drop */
264#define ICMP_UNREACH_SRCFAIL 5 /* src route failed */
265#define ICMP_UNREACH_NET_UNKNOWN 6 /* unknown net */
266#define ICMP_UNREACH_HOST_UNKNOWN 7 /* unknown host */
267#define ICMP_UNREACH_ISOLATED 8 /* src host isolated */
268#define ICMP_UNREACH_NET_PROHIB 9 /* net denied */
269#define ICMP_UNREACH_HOST_PROHIB 10 /* host denied */
270#define ICMP_UNREACH_TOSNET 11 /* bad tos for net */
271#define ICMP_UNREACH_TOSHOST 12 /* bad tos for host */
272#define ICMP_UNREACH_FILTER_PROHIB 13 /* admin prohib */
273#define ICMP_UNREACH_HOST_PRECEDENCE 14 /* host prec vio. */
274#define ICMP_UNREACH_PRECEDENCE_CUTOFF 15 /* prec cutoff */
275
276/* REDIRECT codes */
277#define ICMP_REDIRECT_NET 0 /* for network */
278#define ICMP_REDIRECT_HOST 1 /* for host */
279#define ICMP_REDIRECT_TOSNET 2 /* for tos and net */
280#define ICMP_REDIRECT_TOSHOST 3 /* for tos and host */
281
282/* TIMEXCEED codes */
283#define ICMP_TIMXCEED_INTRANS 0 /* ttl==0 in transit */
284#define ICMP_TIMXCEED_REASS 1 /* ttl==0 in reass */
285
286/* PARAMPROB code */
287#define ICMP_PARAMPROB_OPTABSENT 1 /* req. opt. absent */
288
289#define ICMP_INFOTYPE(type) \
290 ((type) == ICMP_ECHOREPLY || (type) == ICMP_ECHO \
291 || (type) == ICMP_ROUTERADVERT || (type) == ICMP_ROUTERSOLICIT \
292 || (type) == ICMP_TSTAMP || (type) == ICMP_TSTAMPREPLY \
293 || (type) == ICMP_IREQ || (type) == ICMP_IREQREPLY \
294 || (type) == ICMP_MASKREQ || (type) == ICMP_MASKREPLY)
295
296#endif /* __USE_MISC */
297
298__END_DECLS
299
300#endif /* netinet/ip_icmp.h */