1/* $OpenBSD: ip_icmp.h,v 1.33 2025/03/02 21:28:32 bluhm Exp $ */
2/* $NetBSD: ip_icmp.h,v 1.10 1996/02/13 23:42:28 christos Exp $ */
3
4/*
5 * Copyright (c) 1982, 1986, 1993
6 * The Regents of the University of California. All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 * @(#)ip_icmp.h 8.1 (Berkeley) 6/10/93
33 */
34
35#ifndef _NETINET_IP_ICMP_H_
36#define _NETINET_IP_ICMP_H_
37
38/*
39 * Interface Control Message Protocol Definitions.
40 * Per RFC 792, September 1981.
41 * RFC 950, August 1985. (Address Mask Request / Reply)
42 * RFC 1256, September 1991. (Router Advertisement and Solicitation)
43 * RFC 1108, November 1991. (Param Problem, Missing Req. Option)
44 * RFC 1393, January 1993. (Traceroute)
45 * RFC 1475, June 1993. (Datagram Conversion Error)
46 * RFC 1812, June 1995. (adm prohib, host precedence, precedence cutoff)
47 * RFC 2002, October 1996. (Mobility changes to Router Advertisement)
48 */
49
50/*
51 * ICMP Router Advertisement data
52 */
53struct icmp_ra_addr {
54 u_int32_t ira_addr;
55 u_int32_t ira_preference;
56};
57
58/*
59 * Structure of an icmp header.
60 */
61struct icmp {
62 u_int8_t icmp_type; /* type of message, see below */
63 u_int8_t icmp_code; /* type sub code */
64 u_int16_t icmp_cksum; /* ones complement cksum of struct */
65 union {
66 u_int8_t ih_pptr; /* ICMP_PARAMPROB */
67 struct ih_exthdr { /* RFC4884 extended header */
68 u_int8_t iex_pad;
69 u_int8_t iex_length;
70 } ih_exthdr;
71 struct in_addr ih_gwaddr; /* ICMP_REDIRECT */
72 struct ih_idseq {
73 u_int16_t icd_id;
74 u_int16_t icd_seq;
75 } ih_idseq;
76 int32_t ih_void;
77
78 /* ICMP_UNREACH_NEEDFRAG -- Path MTU Discovery (RFC1191) */
79 struct ih_pmtu {
80 u_int16_t ipm_void;
81 u_int16_t ipm_nextmtu;
82 } ih_pmtu;
83
84 struct ih_rtradv {
85 u_int8_t irt_num_addrs;
86 u_int8_t irt_wpa;
87 u_int16_t irt_lifetime;
88 } ih_rtradv;
89 } icmp_hun;
90#define icmp_pptr icmp_hun.ih_pptr
91#define icmp_length icmp_hun.ih_exthdr.iex_length
92#define icmp_gwaddr icmp_hun.ih_gwaddr
93#define icmp_id icmp_hun.ih_idseq.icd_id
94#define icmp_seq icmp_hun.ih_idseq.icd_seq
95#define icmp_void icmp_hun.ih_void
96#define icmp_pmvoid icmp_hun.ih_pmtu.ipm_void
97#define icmp_nextmtu icmp_hun.ih_pmtu.ipm_nextmtu
98#define icmp_num_addrs icmp_hun.ih_rtradv.irt_num_addrs
99#define icmp_wpa icmp_hun.ih_rtradv.irt_wpa
100#define icmp_lifetime icmp_hun.ih_rtradv.irt_lifetime
101 union {
102 struct id_ts {
103 u_int32_t its_otime;
104 u_int32_t its_rtime;
105 u_int32_t its_ttime;
106 } id_ts;
107 struct id_ip {
108 struct ip idi_ip;
109 /* options and then 64 bits of data */
110 } id_ip;
111 u_int32_t id_mask;
112 int8_t id_data[1];
113 } icmp_dun;
114#define icmp_otime icmp_dun.id_ts.its_otime
115#define icmp_rtime icmp_dun.id_ts.its_rtime
116#define icmp_ttime icmp_dun.id_ts.its_ttime
117#define icmp_ip icmp_dun.id_ip.idi_ip
118#define icmp_mask icmp_dun.id_mask
119#define icmp_data icmp_dun.id_data
120};
121
122struct icmp_ext_hdr {
123 u_int8_t ieh_version; /* only high nibble used */
124 u_int8_t ieh_res; /* reserved, must be zero */
125 u_int16_t ieh_cksum; /* ones complement cksum of ext hdr */
126};
127
128#define ICMP_EXT_HDR_VERSION 0x20
129#define ICMP_EXT_HDR_VMASK 0xf0
130#define ICMP_EXT_OFFSET 128
131
132struct icmp_ext_obj_hdr {
133 u_int16_t ieo_length; /* length of obj incl this header */
134 u_int8_t ieo_cnum; /* class number */
135 u_int8_t ieo_ctype; /* sub class type */
136};
137
138#define ICMP_EXT_MPLS 1
139#define ICMP_EXT_IFINFO 2
140
141/*
142 * For IPv6 transition related ICMP errors.
143 */
144#define ICMP_V6ADVLENMIN (8 + sizeof(struct ip) + 40)
145#define ICMP_V6ADVLEN(p) (8 + ((p)->icmp_ip.ip_hl << 2) + 40)
146
147/*
148 * Lower bounds on packet lengths for various types.
149 * For the error advice packets must first insure that the
150 * packet is large enough to contain the returned ip header.
151 * Only then can we do the check to see if 64 bits of packet
152 * data have been returned, since we need to check the returned
153 * ip header length.
154 */
155#define ICMP_MINLEN 8 /* abs minimum */
156#define ICMP_TSLEN (8 + 3 * sizeof (u_int32_t)) /* timestamp */
157#define ICMP_MASKLEN 12 /* address mask */
158#define ICMP_ADVLENMIN (8 + sizeof (struct ip) + 8) /* min */
159#define ICMP_ADVLENMAX (8 + 60 + 40) /* maximum */
160#define ICMP_ADVLEN(p) (8 + ((p)->icmp_ip.ip_hl << 2) + 8)
161 /* N.B.: must separately check that ip_hl >= 5 */
162
163/*
164 * Definition of type and code field values.
165 * https://www.iana.org/assignments/icmp-parameters
166 */
167#define ICMP_ECHOREPLY 0 /* echo reply */
168#define ICMP_UNREACH 3 /* dest unreachable, codes: */
169#define ICMP_UNREACH_NET 0 /* bad net */
170#define ICMP_UNREACH_HOST 1 /* bad host */
171#define ICMP_UNREACH_PROTOCOL 2 /* bad protocol */
172#define ICMP_UNREACH_PORT 3 /* bad port */
173#define ICMP_UNREACH_NEEDFRAG 4 /* IP_DF caused drop */
174#define ICMP_UNREACH_SRCFAIL 5 /* src route failed */
175#define ICMP_UNREACH_NET_UNKNOWN 6 /* unknown net */
176#define ICMP_UNREACH_HOST_UNKNOWN 7 /* unknown host */
177#define ICMP_UNREACH_ISOLATED 8 /* src host isolated */
178#define ICMP_UNREACH_NET_PROHIB 9 /* for crypto devs */
179#define ICMP_UNREACH_HOST_PROHIB 10 /* ditto */
180#define ICMP_UNREACH_TOSNET 11 /* bad tos for net */
181#define ICMP_UNREACH_TOSHOST 12 /* bad tos for host */
182#define ICMP_UNREACH_FILTER_PROHIB 13 /* prohibited access */
183#define ICMP_UNREACH_HOST_PRECEDENCE 14 /* precedence violat'n*/
184#define ICMP_UNREACH_PRECEDENCE_CUTOFF 15 /* precedence cutoff */
185#define ICMP_SOURCEQUENCH 4 /* packet lost, slow down */
186#define ICMP_REDIRECT 5 /* shorter route, codes: */
187#define ICMP_REDIRECT_NET 0 /* for network */
188#define ICMP_REDIRECT_HOST 1 /* for host */
189#define ICMP_REDIRECT_TOSNET 2 /* for tos and net */
190#define ICMP_REDIRECT_TOSHOST 3 /* for tos and host */
191#define ICMP_ALTHOSTADDR 6 /* alternate host address */
192#define ICMP_ECHO 8 /* echo service */
193#define ICMP_ROUTERADVERT 9 /* router advertisement */
194#define ICMP_ROUTERADVERT_NORMAL 0 /* normal advertisement */
195#define ICMP_ROUTERADVERT_NOROUTE_COMMON 16 /* selective routing */
196#define ICMP_ROUTERSOLICIT 10 /* router solicitation */
197#define ICMP_TIMXCEED 11 /* time exceeded, code: */
198#define ICMP_TIMXCEED_INTRANS 0 /* ttl==0 in transit */
199#define ICMP_TIMXCEED_REASS 1 /* ttl==0 in reass */
200#define ICMP_PARAMPROB 12 /* ip header bad */
201#define ICMP_PARAMPROB_ERRATPTR 0 /* req. opt. absent */
202#define ICMP_PARAMPROB_OPTABSENT 1 /* req. opt. absent */
203#define ICMP_PARAMPROB_LENGTH 2 /* bad length */
204#define ICMP_TSTAMP 13 /* timestamp request */
205#define ICMP_TSTAMPREPLY 14 /* timestamp reply */
206#define ICMP_IREQ 15 /* information request */
207#define ICMP_IREQREPLY 16 /* information reply */
208#define ICMP_MASKREQ 17 /* address mask request */
209#define ICMP_MASKREPLY 18 /* address mask reply */
210#define ICMP_TRACEROUTE 30 /* traceroute */
211#define ICMP_DATACONVERR 31 /* data conversion error */
212#define ICMP_MOBILE_REDIRECT 32 /* mobile host redirect */
213#define ICMP_IPV6_WHEREAREYOU 33 /* IPv6 where-are-you */
214#define ICMP_IPV6_IAMHERE 34 /* IPv6 i-am-here */
215#define ICMP_MOBILE_REGREQUEST 35 /* mobile registration req */
216#define ICMP_MOBILE_REGREPLY 36 /* mobile registration reply */
217#define ICMP_SKIP 39 /* SKIP */
218#define ICMP_PHOTURIS 40 /* Photuris */
219#define ICMP_PHOTURIS_UNKNOWN_INDEX 1 /* unknown sec index */
220#define ICMP_PHOTURIS_AUTH_FAILED 2 /* auth failed */
221#define ICMP_PHOTURIS_DECRYPT_FAILED 3 /* decrypt failed */
222
223#define ICMP_MAXTYPE 40
224
225#define ICMP_INFOTYPE(type) \
226 ((type) == ICMP_ECHOREPLY || (type) == ICMP_ECHO || \
227 (type) == ICMP_ROUTERADVERT || (type) == ICMP_ROUTERSOLICIT || \
228 (type) == ICMP_TSTAMP || (type) == ICMP_TSTAMPREPLY || \
229 (type) == ICMP_IREQ || (type) == ICMP_IREQREPLY || \
230 (type) == ICMP_MASKREQ || (type) == ICMP_MASKREPLY)
231
232#ifdef _KERNEL
233struct mbuf *
234 icmp_do_error(struct mbuf *, int, int, u_int32_t, int);
235void icmp_error(struct mbuf *, int, int, u_int32_t, int);
236int icmp_input(struct mbuf **, int *, int, int, struct netstack *);
237void icmp_init(void);
238int icmp_reflect(struct mbuf *, struct mbuf **, struct in_ifaddr *);
239void icmp_send(struct mbuf *, struct mbuf *);
240int icmp_sysctl(int *, u_int, void *, size_t *, void *, size_t);
241struct rtentry *
242 icmp_mtudisc_clone(struct in_addr, u_int, int);
243void icmp_mtudisc(struct icmp *, u_int);
244int icmp_do_exthdr(struct mbuf *, u_int16_t, u_int8_t, void *, size_t);
245#endif /* _KERNEL */
246#endif /* _NETINET_IP_ICMP_H_ */