xref: /original-bsd/sys/netinet/ip_icmp.h (revision ad93c43e)
1 /*
2  * Copyright (c) 1982, 1986 Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms are permitted
6  * provided that this notice is preserved and that due credit is given
7  * to the University of California at Berkeley. The name of the University
8  * may not be used to endorse or promote products derived from this
9  * software without specific prior written permission. This software
10  * is provided ``as is'' without express or implied warranty.
11  *
12  *	@(#)ip_icmp.h	7.3 (Berkeley) 12/07/87
13  */
14 
15 /*
16  * Interface Control Message Protocol Definitions.
17  * Per RFC 792, September 1981.
18  */
19 
20 /*
21  * Structure of an icmp header.
22  */
23 struct icmp {
24 	u_char	icmp_type;		/* type of message, see below */
25 	u_char	icmp_code;		/* type sub code */
26 	u_short	icmp_cksum;		/* ones complement cksum of struct */
27 	union {
28 		u_char ih_pptr;			/* ICMP_PARAMPROB */
29 		struct in_addr ih_gwaddr;	/* ICMP_REDIRECT */
30 		struct ih_idseq {
31 			n_short	icd_id;
32 			n_short	icd_seq;
33 		} ih_idseq;
34 		int ih_void;
35 	} icmp_hun;
36 #define	icmp_pptr	icmp_hun.ih_pptr
37 #define	icmp_gwaddr	icmp_hun.ih_gwaddr
38 #define	icmp_id		icmp_hun.ih_idseq.icd_id
39 #define	icmp_seq	icmp_hun.ih_idseq.icd_seq
40 #define	icmp_void	icmp_hun.ih_void
41 	union {
42 		struct id_ts {
43 			n_time its_otime;
44 			n_time its_rtime;
45 			n_time its_ttime;
46 		} id_ts;
47 		struct id_ip  {
48 			struct ip idi_ip;
49 			/* options and then 64 bits of data */
50 		} id_ip;
51 		u_long	id_mask;
52 		char	id_data[1];
53 	} icmp_dun;
54 #define	icmp_otime	icmp_dun.id_ts.its_otime
55 #define	icmp_rtime	icmp_dun.id_ts.its_rtime
56 #define	icmp_ttime	icmp_dun.id_ts.its_ttime
57 #define	icmp_ip		icmp_dun.id_ip.idi_ip
58 #define	icmp_mask	icmp_dun.id_mask
59 #define	icmp_data	icmp_dun.id_data
60 };
61 
62 /*
63  * Lower bounds on packet lengths for various types.
64  * For the error advice packets must first insure that the
65  * packet is large enought to contain the returned ip header.
66  * Only then can we do the check to see if 64 bits of packet
67  * data have been returned, since we need to check the returned
68  * ip header length.
69  */
70 #define	ICMP_MINLEN	8				/* abs minimum */
71 #define	ICMP_TSLEN	(8 + 3 * sizeof (n_time))	/* timestamp */
72 #define	ICMP_MASKLEN	12				/* address mask */
73 #define	ICMP_ADVLENMIN	(8 + sizeof (struct ip) + 8)	/* min */
74 #define	ICMP_ADVLEN(p)	(8 + ((p)->icmp_ip.ip_hl << 2) + 8)
75 	/* N.B.: must separately check that ip_hl >= 5 */
76 
77 /*
78  * Definition of type and code field values.
79  */
80 #define	ICMP_ECHOREPLY		0		/* echo reply */
81 #define	ICMP_UNREACH		3		/* dest unreachable, codes: */
82 #define		ICMP_UNREACH_NET	0		/* bad net */
83 #define		ICMP_UNREACH_HOST	1		/* bad host */
84 #define		ICMP_UNREACH_PROTOCOL	2		/* bad protocol */
85 #define		ICMP_UNREACH_PORT	3		/* bad port */
86 #define		ICMP_UNREACH_NEEDFRAG	4		/* IP_DF caused drop */
87 #define		ICMP_UNREACH_SRCFAIL	5		/* src route failed */
88 #define	ICMP_SOURCEQUENCH	4		/* packet lost, slow down */
89 #define	ICMP_REDIRECT		5		/* shorter route, codes: */
90 #define		ICMP_REDIRECT_NET	0		/* for network */
91 #define		ICMP_REDIRECT_HOST	1		/* for host */
92 #define		ICMP_REDIRECT_TOSNET	2		/* for tos and net */
93 #define		ICMP_REDIRECT_TOSHOST	3		/* for tos and host */
94 #define	ICMP_ECHO		8		/* echo service */
95 #define	ICMP_TIMXCEED		11		/* time exceeded, code: */
96 #define		ICMP_TIMXCEED_INTRANS	0		/* ttl==0 in transit */
97 #define		ICMP_TIMXCEED_REASS	1		/* ttl==0 in reass */
98 #define	ICMP_PARAMPROB		12		/* ip header bad */
99 #define	ICMP_TSTAMP		13		/* timestamp request */
100 #define	ICMP_TSTAMPREPLY	14		/* timestamp reply */
101 #define	ICMP_IREQ		15		/* information request */
102 #define	ICMP_IREQREPLY		16		/* information reply */
103 #define	ICMP_MASKREQ		17		/* address mask request */
104 #define	ICMP_MASKREPLY		18		/* address mask reply */
105 
106 #define	ICMP_MAXTYPE		18
107 
108 #define	ICMP_INFOTYPE(type) \
109 	((type) == ICMP_ECHOREPLY || (type) == ICMP_ECHO || \
110 	(type) == ICMP_TSTAMP || (type) == ICMP_TSTAMPREPLY || \
111 	(type) == ICMP_IREQ || (type) == ICMP_IREQREPLY || \
112 	(type) == ICMP_MASKREQ || (type) == ICMP_MASKREPLY)
113