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_icmp.h	8.1 (Berkeley) 6/10/93
30 * ip_icmp.h,v 1.4 1995/05/30 08:09:43 rgrimes Exp
31 */
32
33#ifndef _NETINET_IP_ICMP_H_
34#define _NETINET_IP_ICMP_H_
35
36/*
37 * Interface Control Message Protocol Definitions.
38 * Per RFC 792, September 1981.
39 */
40
41typedef u_int32_t n_time;
42
43/*
44 * Structure of an icmp header.
45 */
46struct icmp {
47	u_char	icmp_type;		/* type of message, see below */
48	u_char	icmp_code;		/* type sub code */
49	u_short	icmp_cksum;		/* ones complement cksum of struct */
50	union {
51		u_char ih_pptr;			/* ICMP_PARAMPROB */
52		struct in_addr ih_gwaddr;	/* ICMP_REDIRECT */
53		struct ih_idseq {
54			u_short	icd_id;
55			u_short	icd_seq;
56		} ih_idseq;
57		int ih_void;
58
59		/* ICMP_UNREACH_NEEDFRAG -- Path MTU Discovery (RFC1191) */
60		struct ih_pmtu {
61			u_short ipm_void;
62			u_short ipm_nextmtu;
63		} ih_pmtu;
64	} icmp_hun;
65#define	icmp_pptr	icmp_hun.ih_pptr
66#define	icmp_gwaddr	icmp_hun.ih_gwaddr
67#define	icmp_id		icmp_hun.ih_idseq.icd_id
68#define	icmp_seq	icmp_hun.ih_idseq.icd_seq
69#define	icmp_void	icmp_hun.ih_void
70#define	icmp_pmvoid	icmp_hun.ih_pmtu.ipm_void
71#define	icmp_nextmtu	icmp_hun.ih_pmtu.ipm_nextmtu
72	union {
73		struct id_ts {
74			n_time its_otime;
75			n_time its_rtime;
76			n_time its_ttime;
77		} id_ts;
78		struct id_ip  {
79			struct ip idi_ip;
80			/* options and then 64 bits of data */
81		} id_ip;
82		uint32_t	id_mask;
83		char		id_data[1];
84	} icmp_dun;
85#define	icmp_otime	icmp_dun.id_ts.its_otime
86#define	icmp_rtime	icmp_dun.id_ts.its_rtime
87#define	icmp_ttime	icmp_dun.id_ts.its_ttime
88#define	icmp_ip		icmp_dun.id_ip.idi_ip
89#define	icmp_mask	icmp_dun.id_mask
90#define	icmp_data	icmp_dun.id_data
91};
92
93/*
94 * Lower bounds on packet lengths for various types.
95 * For the error advice packets must first insure that the
96 * packet is large enought to contain the returned ip header.
97 * Only then can we do the check to see if 64 bits of packet
98 * data have been returned, since we need to check the returned
99 * ip header length.
100 */
101#define	ICMP_MINLEN	8				/* abs minimum */
102#define	ICMP_TSLEN	(8 + 3 * sizeof (n_time))	/* timestamp */
103#define	ICMP_MASKLEN	12				/* address mask */
104#define	ICMP_ADVLENMIN	(8 + sizeof (struct ip) + 8)	/* min */
105#define	ICMP_ADVLEN(p)	(8 + ((p)->icmp_ip.ip_hl << 2) + 8)
106	/* N.B.: must separately check that ip_hl >= 5 */
107
108/*
109 * Definition of type and code field values.
110 */
111#define	ICMP_ECHOREPLY		0		/* echo reply */
112#define	ICMP_UNREACH		3		/* dest unreachable, codes: */
113#define		ICMP_UNREACH_NET	0		/* bad net */
114#define		ICMP_UNREACH_HOST	1		/* bad host */
115#define		ICMP_UNREACH_PROTOCOL	2		/* bad protocol */
116#define		ICMP_UNREACH_PORT	3		/* bad port */
117#define		ICMP_UNREACH_NEEDFRAG	4		/* IP_DF caused drop */
118#define		ICMP_UNREACH_SRCFAIL	5		/* src route failed */
119#define		ICMP_UNREACH_NET_UNKNOWN 6		/* unknown net */
120#define		ICMP_UNREACH_HOST_UNKNOWN 7		/* unknown host */
121#define		ICMP_UNREACH_ISOLATED	8		/* src host isolated */
122#define		ICMP_UNREACH_NET_PROHIB	9		/* prohibited access */
123#define		ICMP_UNREACH_HOST_PROHIB 10		/* ditto */
124#define		ICMP_UNREACH_TOSNET	11		/* bad tos for net */
125#define		ICMP_UNREACH_TOSHOST	12		/* bad tos for host */
126#define	ICMP_SOURCEQUENCH	4		/* packet lost, slow down */
127#define	ICMP_REDIRECT		5		/* shorter route, codes: */
128#define		ICMP_REDIRECT_NET	0		/* for network */
129#define		ICMP_REDIRECT_HOST	1		/* for host */
130#define		ICMP_REDIRECT_TOSNET	2		/* for tos and net */
131#define		ICMP_REDIRECT_TOSHOST	3		/* for tos and host */
132#define	ICMP_ECHO		8		/* echo service */
133#define	ICMP_ROUTERADVERT	9		/* router advertisement */
134#define	ICMP_ROUTERSOLICIT	10		/* router solicitation */
135#define	ICMP_TIMXCEED		11		/* time exceeded, code: */
136#define		ICMP_TIMXCEED_INTRANS	0		/* ttl==0 in transit */
137#define		ICMP_TIMXCEED_REASS	1		/* ttl==0 in reass */
138#define	ICMP_PARAMPROB		12		/* ip header bad */
139#define		ICMP_PARAMPROB_OPTABSENT 1		/* req. opt. absent */
140#define	ICMP_TSTAMP		13		/* timestamp request */
141#define	ICMP_TSTAMPREPLY	14		/* timestamp reply */
142#define	ICMP_IREQ		15		/* information request */
143#define	ICMP_IREQREPLY		16		/* information reply */
144#define	ICMP_MASKREQ		17		/* address mask request */
145#define	ICMP_MASKREPLY		18		/* address mask reply */
146
147#define	ICMP_MAXTYPE		18
148
149#define	ICMP_INFOTYPE(type) \
150	((type) == ICMP_ECHOREPLY || (type) == ICMP_ECHO || \
151	(type) == ICMP_ROUTERADVERT || (type) == ICMP_ROUTERSOLICIT || \
152	(type) == ICMP_TSTAMP || (type) == ICMP_TSTAMPREPLY || \
153	(type) == ICMP_IREQ || (type) == ICMP_IREQREPLY || \
154	(type) == ICMP_MASKREQ || (type) == ICMP_MASKREPLY)
155
156void icmp_input _P((struct mbuf *, int));
157void icmp_error(struct mbuf *msrc, u_char type, u_char code, int minsize,
158                const char *message);
159void icmp_reflect _P((struct mbuf *));
160
161#endif
162