1 /* 2 * Copyright (c) 1982, 1986 Regents of the University of California. 3 * All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 * 7 * @(#)ip_icmp.h 7.5 (Berkeley) 06/28/90 8 */ 9 10 /* 11 * Interface Control Message Protocol Definitions. 12 * Per RFC 792, September 1981. 13 */ 14 15 /* 16 * Structure of an icmp header. 17 */ 18 struct icmp { 19 u_char icmp_type; /* type of message, see below */ 20 u_char icmp_code; /* type sub code */ 21 u_short icmp_cksum; /* ones complement cksum of struct */ 22 union { 23 u_char ih_pptr; /* ICMP_PARAMPROB */ 24 struct in_addr ih_gwaddr; /* ICMP_REDIRECT */ 25 struct ih_idseq { 26 n_short icd_id; 27 n_short icd_seq; 28 } ih_idseq; 29 int ih_void; 30 } icmp_hun; 31 #define icmp_pptr icmp_hun.ih_pptr 32 #define icmp_gwaddr icmp_hun.ih_gwaddr 33 #define icmp_id icmp_hun.ih_idseq.icd_id 34 #define icmp_seq icmp_hun.ih_idseq.icd_seq 35 #define icmp_void icmp_hun.ih_void 36 union { 37 struct id_ts { 38 n_time its_otime; 39 n_time its_rtime; 40 n_time its_ttime; 41 } id_ts; 42 struct id_ip { 43 struct ip idi_ip; 44 /* options and then 64 bits of data */ 45 } id_ip; 46 u_long id_mask; 47 char id_data[1]; 48 } icmp_dun; 49 #define icmp_otime icmp_dun.id_ts.its_otime 50 #define icmp_rtime icmp_dun.id_ts.its_rtime 51 #define icmp_ttime icmp_dun.id_ts.its_ttime 52 #define icmp_ip icmp_dun.id_ip.idi_ip 53 #define icmp_mask icmp_dun.id_mask 54 #define icmp_data icmp_dun.id_data 55 }; 56 57 /* 58 * Lower bounds on packet lengths for various types. 59 * For the error advice packets must first insure that the 60 * packet is large enought to contain the returned ip header. 61 * Only then can we do the check to see if 64 bits of packet 62 * data have been returned, since we need to check the returned 63 * ip header length. 64 */ 65 #define ICMP_MINLEN 8 /* abs minimum */ 66 #define ICMP_TSLEN (8 + 3 * sizeof (n_time)) /* timestamp */ 67 #define ICMP_MASKLEN 12 /* address mask */ 68 #define ICMP_ADVLENMIN (8 + sizeof (struct ip) + 8) /* min */ 69 #define ICMP_ADVLEN(p) (8 + ((p)->icmp_ip.ip_hl << 2) + 8) 70 /* N.B.: must separately check that ip_hl >= 5 */ 71 72 /* 73 * Definition of type and code field values. 74 */ 75 #define ICMP_ECHOREPLY 0 /* echo reply */ 76 #define ICMP_UNREACH 3 /* dest unreachable, codes: */ 77 #define ICMP_UNREACH_NET 0 /* bad net */ 78 #define ICMP_UNREACH_HOST 1 /* bad host */ 79 #define ICMP_UNREACH_PROTOCOL 2 /* bad protocol */ 80 #define ICMP_UNREACH_PORT 3 /* bad port */ 81 #define ICMP_UNREACH_NEEDFRAG 4 /* IP_DF caused drop */ 82 #define ICMP_UNREACH_SRCFAIL 5 /* src route failed */ 83 #define ICMP_SOURCEQUENCH 4 /* packet lost, slow down */ 84 #define ICMP_REDIRECT 5 /* shorter route, codes: */ 85 #define ICMP_REDIRECT_NET 0 /* for network */ 86 #define ICMP_REDIRECT_HOST 1 /* for host */ 87 #define ICMP_REDIRECT_TOSNET 2 /* for tos and net */ 88 #define ICMP_REDIRECT_TOSHOST 3 /* for tos and host */ 89 #define ICMP_ECHO 8 /* echo service */ 90 #define ICMP_TIMXCEED 11 /* time exceeded, code: */ 91 #define ICMP_TIMXCEED_INTRANS 0 /* ttl==0 in transit */ 92 #define ICMP_TIMXCEED_REASS 1 /* ttl==0 in reass */ 93 #define ICMP_PARAMPROB 12 /* ip header bad */ 94 #define ICMP_TSTAMP 13 /* timestamp request */ 95 #define ICMP_TSTAMPREPLY 14 /* timestamp reply */ 96 #define ICMP_IREQ 15 /* information request */ 97 #define ICMP_IREQREPLY 16 /* information reply */ 98 #define ICMP_MASKREQ 17 /* address mask request */ 99 #define ICMP_MASKREPLY 18 /* address mask reply */ 100 101 #define ICMP_MAXTYPE 18 102 103 #define ICMP_INFOTYPE(type) \ 104 ((type) == ICMP_ECHOREPLY || (type) == ICMP_ECHO || \ 105 (type) == ICMP_TSTAMP || (type) == ICMP_TSTAMPREPLY || \ 106 (type) == ICMP_IREQ || (type) == ICMP_IREQREPLY || \ 107 (type) == ICMP_MASKREQ || (type) == ICMP_MASKREPLY) 108