/* Copyright (C) 1998 Free Software Foundation, Inc. This file is part of GNU Inetutils. GNU Inetutils is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GNU Inetutils is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNU Inetutils; see the file COPYING. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* * Structure of an icmp header. */ typedef struct icmp_header icmphdr_t; struct icmp_header { u_char icmp_type; /* type of message, see below */ u_char icmp_code; /* type sub code */ u_short icmp_cksum; /* ones complement cksum of struct */ union { u_char ih_pptr; /* ICMP_PARAMPROB */ struct in_addr ih_gwaddr; /* ICMP_REDIRECT */ struct ih_idseq { u_short icd_id; u_short icd_seq; } ih_idseq; int ih_void; /* ICMP_UNREACH_NEEDFRAG -- Path MTU discovery as per rfc 1191 */ struct ih_pmtu { u_short ipm_void; u_short ipm_nextmtu; } ih_pmtu; /* ICMP_ROUTERADV -- RFC 1256 */ struct ih_rtradv { u_char irt_num_addrs; /* Number of addresses following the msg */ u_char irt_wpa; /* Address Entry Size (32-bit words) */ u_short irt_lifetime; /* Lifetime */ } ih_rtradv; } icmp_hun; #define icmp_pptr icmp_hun.ih_pptr #define icmp_gwaddr icmp_hun.ih_gwaddr #define icmp_id icmp_hun.ih_idseq.icd_id #define icmp_seq icmp_hun.ih_idseq.icd_seq #define icmp_void icmp_hun.ih_void #define icmp_pmvoid icmp_hun.ih_pmtu.ipm_void #define icmp_nextmtu icmp_hun.ih_pmtu.ipm_nextmtu #define icmp_num_addrs icmp_hun.ih_rtradv.irt_num_addrs #define icmp_wpa icmp_hun.ih_rtradv.irt_wpa #define icmp_lifetime icmp_hun.ih_rtradv.irt_lifetime union { struct id_ts /* ICMP_TIMESTAMP, ICMP_TIMESTAMP_REPLY */ { n_time its_otime; /* Originate timestamp */ n_time its_rtime; /* Recieve timestamp */ n_time its_ttime; /* Transmit timestamp */ } id_ts; struct id_ip /* Original IP header */ { struct ip idi_ip; /* options and then 64 bits of data */ } id_ip; u_long id_mask; /* ICMP_ADDRESS, ICMP_ADDRESSREPLY */ char id_data[1]; } icmp_dun; #define icmp_otime icmp_dun.id_ts.its_otime #define icmp_rtime icmp_dun.id_ts.its_rtime #define icmp_ttime icmp_dun.id_ts.its_ttime #define icmp_ip icmp_dun.id_ip.idi_ip #define icmp_mask icmp_dun.id_mask #define icmp_data icmp_dun.id_data }; #define ICMP_ECHOREPLY 0 /* Echo Reply */ #define ICMP_DEST_UNREACH 3 /* Destination Unreachable */ /* Codes for ICMP_DEST_UNREACH. */ #define ICMP_NET_UNREACH 0 /* Network Unreachable */ #define ICMP_HOST_UNREACH 1 /* Host Unreachable */ #define ICMP_PROT_UNREACH 2 /* Protocol Unreachable */ #define ICMP_PORT_UNREACH 3 /* Port Unreachable */ #define ICMP_FRAG_NEEDED 4 /* Fragmentation Needed/DF set */ #define ICMP_SR_FAILED 5 /* Source Route failed */ #define ICMP_NET_UNKNOWN 6 #define ICMP_HOST_UNKNOWN 7 #define ICMP_HOST_ISOLATED 8 #define ICMP_NET_ANO 9 #define ICMP_HOST_ANO 10 #define ICMP_NET_UNR_TOS 11 #define ICMP_HOST_UNR_TOS 12 #define ICMP_PKT_FILTERED 13 /* Packet filtered */ #define ICMP_PREC_VIOLATION 14 /* Precedence violation */ #define ICMP_PREC_CUTOFF 15 /* Precedence cut off */ #define NR_ICMP_UNREACH 15 /* total subcodes */ #define ICMP_SOURCE_QUENCH 4 /* Source Quench */ #define ICMP_REDIRECT 5 /* Redirect (change route) */ /* Codes for ICMP_REDIRECT. */ #define ICMP_REDIR_NET 0 /* Redirect Net */ #define ICMP_REDIR_HOST 1 /* Redirect Host */ #define ICMP_REDIR_NETTOS 2 /* Redirect Net for TOS */ #define ICMP_REDIR_HOSTTOS 3 /* Redirect Host for TOS */ #define ICMP_ECHO 8 /* Echo Request */ #define ICMP_ROUTERADV 9 /* Router Advertisement -- RFC 1256 */ #define ICMP_ROUTERDISCOVERY 10 /* Router Discovery -- RFC 1256 */ #define ICMP_TIME_EXCEEDED 11 /* Time Exceeded */ /* Codes for TIME_EXCEEDED. */ #define ICMP_EXC_TTL 0 /* TTL count exceeded */ #define ICMP_EXC_FRAGTIME 1 /* Fragment Reass time exceeded */ #define ICMP_PARAMETERPROB 12 /* Parameter Problem */ #define ICMP_TIMESTAMP 13 /* Timestamp Request */ #define ICMP_TIMESTAMPREPLY 14 /* Timestamp Reply */ #define ICMP_INFO_REQUEST 15 /* Information Request */ #define ICMP_INFO_REPLY 16 /* Information Reply */ #define ICMP_ADDRESS 17 /* Address Mask Request */ #define ICMP_ADDRESSREPLY 18 /* Address Mask Reply */ #define NR_ICMP_TYPES 18 #define MAXIPLEN 60 #define MAXICMPLEN 76 #define ICMP_MINLEN 8 /* abs minimum */ #define ICMP_TSLEN (8 + 3 * sizeof (u_long)) /* timestamp */ #define ICMP_MASKLEN 12 /* address mask */ #define ICMP_ADVLENMIN (8 + sizeof (struct ip) + 8) /* min */ #define ICMP_ADVLEN(p) (8 + ((p)->icmp_ip.ip_hl << 2) + 8) /* N.B.: must separately check that ip_hl >= 5 */ u_short icmp_cksum (u_char *addr, int len); int icmp_generic_encode (u_char *buffer, size_t bufsize, int type, int ident, int seqno); int icmp_generic_decode (u_char *buffer, size_t bufsize, struct ip **ipp, icmphdr_t **icmpp); int icmp_echo_encode (u_char *buffer, size_t bufsize, int ident, int seqno); int icmp_echo_decode (u_char *buffer, size_t bufsize, struct ip **ip, icmphdr_t **icmp); int icmp_timestamp_encode (u_char *buffer, size_t bufsize, int ident, int seqno); int icmp_address_encode (u_char *buffer, size_t bufsize, int ident, int seqno);