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 
41 typedef uint32_t n_time;
42 
43 /*
44  * Structure of an icmp header.
45  */
46 struct 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 ensure that the
96  * packet is large enough 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 
156 void icmp_init(Slirp *slirp);
157 void icmp_cleanup(Slirp *slirp);
158 void icmp_input(struct mbuf *, int);
159 void icmp_send_error(struct mbuf *msrc, u_char type, u_char code, int minsize,
160                      const char *message);
161 void icmp_reflect(struct mbuf *);
162 void icmp_receive(struct socket *so);
163 void icmp_detach(struct socket *so);
164 
165 #endif
166