1 /* 2 * Copyright (c) 1982 Regents of the University of California. 3 * All rights reserved. The Berkeley software License Agreement 4 * specifies the terms and conditions for redistribution. 5 * 6 * @(#)ip_icmp.h 6.4 (Berkeley) 04/12/86 7 */ 8 9 /* 10 * Interface Control Message Protocol Definitions. 11 * Per RFC 792, September 1981. 12 */ 13 14 /* 15 * Structure of an icmp header. 16 */ 17 struct icmp { 18 u_char icmp_type; /* type of message, see below */ 19 u_char icmp_code; /* type sub code */ 20 u_short icmp_cksum; /* ones complement cksum of struct */ 21 union { 22 u_char ih_pptr; /* ICMP_PARAMPROB */ 23 struct in_addr ih_gwaddr; /* ICMP_REDIRECT */ 24 struct ih_idseq { 25 n_short icd_id; 26 n_short icd_seq; 27 } ih_idseq; 28 int ih_void; 29 } icmp_hun; 30 #define icmp_pptr icmp_hun.ih_pptr 31 #define icmp_gwaddr icmp_hun.ih_gwaddr 32 #define icmp_id icmp_hun.ih_idseq.icd_id 33 #define icmp_seq icmp_hun.ih_idseq.icd_seq 34 #define icmp_void icmp_hun.ih_void 35 union { 36 struct id_ts { 37 n_time its_otime; 38 n_time its_rtime; 39 n_time its_ttime; 40 } id_ts; 41 struct id_ip { 42 struct ip idi_ip; 43 /* options and then 64 bits of data */ 44 } id_ip; 45 u_long id_mask; 46 char id_data[1]; 47 } icmp_dun; 48 #define icmp_otime icmp_dun.id_ts.its_otime 49 #define icmp_rtime icmp_dun.id_ts.its_rtime 50 #define icmp_ttime icmp_dun.id_ts.its_ttime 51 #define icmp_ip icmp_dun.id_ip.idi_ip 52 #define icmp_mask icmp_dun.id_mask 53 #define icmp_data icmp_dun.id_data 54 }; 55 56 /* 57 * Lower bounds on packet lengths for various types. 58 * For the error advice packets must first insure that the 59 * packet is large enought to contain the returned ip header. 60 * Only then can we do the check to see if 64 bits of packet 61 * data have been returned, since we need to check the returned 62 * ip header length. 63 */ 64 #define ICMP_MINLEN 8 /* abs minimum */ 65 #define ICMP_TSLEN (8 + 3 * sizeof (n_time)) /* timestamp */ 66 #define ICMP_MASKLEN 12 /* address mask */ 67 #define ICMP_ADVLENMIN (8 + sizeof (struct ip) + 8) /* min */ 68 #define ICMP_ADVLEN(p) (8 + ((p)->icmp_ip.ip_hl << 2) + 8) 69 /* N.B.: must separately check that ip_hl >= 5 */ 70 71 /* 72 * Definition of type and code field values. 73 */ 74 #define ICMP_ECHOREPLY 0 /* echo reply */ 75 #define ICMP_UNREACH 3 /* dest unreachable, codes: */ 76 #define ICMP_UNREACH_NET 0 /* bad net */ 77 #define ICMP_UNREACH_HOST 1 /* bad host */ 78 #define ICMP_UNREACH_PROTOCOL 2 /* bad protocol */ 79 #define ICMP_UNREACH_PORT 3 /* bad port */ 80 #define ICMP_UNREACH_NEEDFRAG 4 /* IP_DF caused drop */ 81 #define ICMP_UNREACH_SRCFAIL 5 /* src route failed */ 82 #define ICMP_SOURCEQUENCH 4 /* packet lost, slow down */ 83 #define ICMP_REDIRECT 5 /* shorter route, codes: */ 84 #define ICMP_REDIRECT_NET 0 /* for network */ 85 #define ICMP_REDIRECT_HOST 1 /* for host */ 86 #define ICMP_REDIRECT_TOSNET 2 /* for tos and net */ 87 #define ICMP_REDIRECT_TOSHOST 3 /* for tos and host */ 88 #define ICMP_ECHO 8 /* echo service */ 89 #define ICMP_TIMXCEED 11 /* time exceeded, code: */ 90 #define ICMP_TIMXCEED_INTRANS 0 /* ttl==0 in transit */ 91 #define ICMP_TIMXCEED_REASS 1 /* ttl==0 in reass */ 92 #define ICMP_PARAMPROB 12 /* ip header bad */ 93 #define ICMP_TSTAMP 13 /* timestamp request */ 94 #define ICMP_TSTAMPREPLY 14 /* timestamp reply */ 95 #define ICMP_IREQ 15 /* information request */ 96 #define ICMP_IREQREPLY 16 /* information reply */ 97 #define ICMP_MASKREQ 17 /* address mask request */ 98 #define ICMP_MASKREPLY 18 /* address mask reply */ 99 100 #define ICMP_MAXTYPE 18 101