1 /*	$NetBSD: ip_icmp.h,v 1.11 1996/08/03 15:48:18 neil Exp $	*/
2 
3 /*
4  * Copyright (c) 1982, 1986, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  *	@(#)ip_icmp.h	8.1 (Berkeley) 6/10/93
32  */
33 
34 
35 /*
36  * Interface Control Message Protocol Definitions.
37  * Per RFC 792, September 1981.
38  */
39 
40 /*
41  * Internal of an ICMP Router Advertisement
42  */
43 struct icmp_ra_addr {
44 	u_int32_t ira_addr;
45 	u_int32_t ira_preference;
46 };
47 
48 /*
49  * Structure of an icmp header.
50  */
51 struct icmp {
52 	u_int8_t  icmp_type;		/* type of message, see below */
53 	u_int8_t  icmp_code;		/* type sub code */
54 	u_int16_t icmp_cksum;		/* ones complement cksum of struct */
55 	union {
56 		u_int8_t  ih_pptr;		/* ICMP_PARAMPROB */
57 		struct in_addr ih_gwaddr;	/* ICMP_REDIRECT */
58 		struct ih_idseq {
59 			  int16_t icd_id;
60 			  int16_t icd_seq;
61 		} ih_idseq;
62 		int32_t   ih_void;
63 
64 		/* ICMP_UNREACH_NEEDFRAG -- Path MTU Discovery (RFC1191) */
65 		struct ih_pmtu {
66 			  int16_t ipm_void;
67 			  int16_t ipm_nextmtu;
68 		} ih_pmtu;
69 		struct ih_rtradv {
70 			u_int8_t irt_num_addrs;
71 			u_int8_t irt_wpa;
72 			u_int16_t irt_lifetime;
73 		} ih_rtradv;
74 	} icmp_hun;
75 #define	icmp_pptr	  icmp_hun.ih_pptr
76 #define	icmp_gwaddr	  icmp_hun.ih_gwaddr
77 #define	icmp_id		  icmp_hun.ih_idseq.icd_id
78 #define	icmp_seq	  icmp_hun.ih_idseq.icd_seq
79 #define	icmp_void	  icmp_hun.ih_void
80 #define	icmp_pmvoid	  icmp_hun.ih_pmtu.ipm_void
81 #define	icmp_nextmtu	  icmp_hun.ih_pmtu.ipm_nextmtu
82 #define icmp_num_addrs    icmp_hun.ih_rtradv.irt_num_addrs
83 #define icmp_wpa	  icmp_hun.ih_rtradv.irt_wpa
84 #define icmp_lifetime	  icmp_hun.ih_rtradv.irt_lifetime
85 	union {
86 		struct id_ts {
87 			  u_int32_t its_otime;
88 			  u_int32_t its_rtime;
89 			  u_int32_t its_ttime;
90 		} id_ts;
91 		struct id_ip  {
92 			  struct ip idi_ip;
93 			  /* options and then 64 bits of data */
94 		} id_ip;
95 		struct icmp_ra_addr id_radv;
96 		u_int32_t id_mask;
97 		int8_t	  id_data[1];
98 	} icmp_dun;
99 #define	icmp_otime	  icmp_dun.id_ts.its_otime
100 #define	icmp_rtime	  icmp_dun.id_ts.its_rtime
101 #define	icmp_ttime	  icmp_dun.id_ts.its_ttime
102 #define	icmp_ip		  icmp_dun.id_ip.idi_ip
103 #define icmp_radv	  icmp_dun.id_mask
104 #define	icmp_mask	  icmp_dun.id_mask
105 #define	icmp_data	  icmp_dun.id_data
106 };
107 
108 /*
109  * Lower bounds on packet lengths for various types.
110  * For the error advice packets must first insure that the
111  * packet is large enought to contain the returned ip header.
112  * Only then can we do the check to see if 64 bits of packet
113  * data have been returned, since we need to check the returned
114  * ip header length.
115  */
116 #define	ICMP_MINLEN	8				/* abs minimum */
117 #define	ICMP_TSLEN	(8 + 3 * sizeof (u_int32_t))	/* timestamp */
118 #define	ICMP_MASKLEN	12				/* address mask */
119 #define	ICMP_ADVLENMIN	(8 + sizeof (struct ip) + 8)	/* min */
120 #define	ICMP_ADVLEN(p)	(8 + ((p)->icmp_ip.ip_hl << 2) + 8)
121 	/* N.B.: must separately check that ip_hl >= 5 */
122 
123 /*
124  * Definition of type and code field values.
125  */
126 #define	ICMP_ECHOREPLY		0		/* echo reply */
127 #define	ICMP_UNREACH		3		/* dest unreachable, codes: */
128 #define		ICMP_UNREACH_NET	0		/* bad net */
129 #define		ICMP_UNREACH_HOST	1		/* bad host */
130 #define		ICMP_UNREACH_PROTOCOL	2		/* bad protocol */
131 #define		ICMP_UNREACH_PORT	3		/* bad port */
132 #define		ICMP_UNREACH_NEEDFRAG	4		/* IP_DF caused drop */
133 #define		ICMP_UNREACH_SRCFAIL	5		/* src route failed */
134 #define		ICMP_UNREACH_NET_UNKNOWN 6		/* unknown net */
135 #define		ICMP_UNREACH_HOST_UNKNOWN 7		/* unknown host */
136 #define		ICMP_UNREACH_ISOLATED	8		/* src host isolated */
137 #define		ICMP_UNREACH_NET_PROHIB	9		/* prohibited access */
138 #define		ICMP_UNREACH_HOST_PROHIB 10		/* ditto */
139 #define		ICMP_UNREACH_TOSNET	11		/* bad tos for net */
140 #define		ICMP_UNREACH_TOSHOST	12		/* bad tos for host */
141 #define	ICMP_SOURCEQUENCH	4		/* packet lost, slow down */
142 #define	ICMP_REDIRECT		5		/* shorter route, codes: */
143 #define		ICMP_REDIRECT_NET	0		/* for network */
144 #define		ICMP_REDIRECT_HOST	1		/* for host */
145 #define		ICMP_REDIRECT_TOSNET	2		/* for tos and net */
146 #define		ICMP_REDIRECT_TOSHOST	3		/* for tos and host */
147 #define	ICMP_ECHO		8		/* echo service */
148 #define	ICMP_ROUTERADVERT	9		/* router advertisement */
149 #define	ICMP_ROUTERSOLICIT	10		/* router solicitation */
150 #define	ICMP_TIMXCEED		11		/* time exceeded, code: */
151 #define		ICMP_TIMXCEED_INTRANS	0		/* ttl==0 in transit */
152 #define		ICMP_TIMXCEED_REASS	1		/* ttl==0 in reass */
153 #define	ICMP_PARAMPROB		12		/* ip header bad */
154 #define		ICMP_PARAMPROB_OPTABSENT 1		/* req. opt. absent */
155 #define	ICMP_TSTAMP		13		/* timestamp request */
156 #define	ICMP_TSTAMPREPLY	14		/* timestamp reply */
157 #define	ICMP_IREQ		15		/* information request */
158 #define	ICMP_IREQREPLY		16		/* information reply */
159 #define	ICMP_MASKREQ		17		/* address mask request */
160 #define	ICMP_MASKREPLY		18		/* address mask reply */
161 
162 #define	ICMP_MAXTYPE		18
163 
164 #define	ICMP_INFOTYPE(type) \
165 	((type) == ICMP_ECHOREPLY || (type) == ICMP_ECHO || \
166 	(type) == ICMP_ROUTERADVERT || (type) == ICMP_ROUTERSOLICIT || \
167 	(type) == ICMP_TSTAMP || (type) == ICMP_TSTAMPREPLY || \
168 	(type) == ICMP_IREQ || (type) == ICMP_IREQREPLY || \
169 	(type) == ICMP_MASKREQ || (type) == ICMP_MASKREPLY)
170 
171 #ifdef _KERNEL
172 void	icmp_error __P((struct mbuf *, int, int, n_long, struct ifnet *));
173 void	icmp_input __P((struct mbuf *, ...));
174 void	icmp_reflect __P((struct mbuf *));
175 void	icmp_send __P((struct mbuf *, struct mbuf *));
176 int	icmp_sysctl __P((int *, u_int, void *, size_t *, void *, size_t));
177 #endif
178 
179