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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-15 17:13:01 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-15 17:13:01 +0000 |
commit | 7adcb5b605cc1328a3084c334f4697ec9771936c (patch) | |
tree | 03e681bfda053978ba896745828e09cb056ad156 /print-icmp.c | |
parent | Initial commit. (diff) | |
download | tcpdump-upstream.tar.xz tcpdump-upstream.zip |
Adding upstream version 4.99.4.upstream/4.99.4upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | print-icmp.c | 797 |
1 files changed, 797 insertions, 0 deletions
diff --git a/print-icmp.c b/print-icmp.c new file mode 100644 index 0000000..54d215e --- /dev/null +++ b/print-icmp.c @@ -0,0 +1,797 @@ +/* + * Copyright (c) 1988, 1989, 1990, 1991, 1993, 1994, 1995, 1996 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that: (1) source code distributions + * retain the above copyright notice and this paragraph in its entirety, (2) + * distributions including binary code include the above copyright notice and + * this paragraph in its entirety in the documentation or other materials + * provided with the distribution, and (3) all advertising materials mentioning + * features or use of this software display the following acknowledgement: + * ``This product includes software developed by the University of California, + * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of + * the University nor the names of its contributors may be used to endorse + * or promote products derived from this software without specific prior + * written permission. + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. + */ + +/* \summary: Internet Control Message Protocol (ICMP) printer */ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include "netdissect-stdinc.h" + +#include <stdio.h> +#include <string.h> + +#include "netdissect.h" +#include "addrtoname.h" +#include "extract.h" + +#include "ip.h" +#include "udp.h" +#include "ipproto.h" +#include "mpls.h" + +/* + * Interface Control Message Protocol Definitions. + * Per RFC 792, September 1981. + */ + +/* + * Structure of an icmp header. + */ +struct icmp { + nd_uint8_t icmp_type; /* type of message, see below */ + nd_uint8_t icmp_code; /* type sub code */ + nd_uint16_t icmp_cksum; /* ones complement cksum of struct */ + union { + nd_uint8_t ih_pptr; /* ICMP_PARAMPROB */ + nd_ipv4 ih_gwaddr; /* ICMP_REDIRECT */ + struct ih_idseq { + nd_uint16_t icd_id; + nd_uint16_t icd_seq; + } ih_idseq; + nd_uint32_t ih_void; + } 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 + union { + struct id_ts { + nd_uint32_t its_otime; + nd_uint32_t its_rtime; + nd_uint32_t its_ttime; + } id_ts; + struct id_ip { + struct ip idi_ip; + /* options and then 64 bits of data */ + } id_ip; + nd_uint32_t id_mask; + nd_byte 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 +}; + +/* + * Lower bounds on packet lengths for various types. + * For the error advice packets must first insure that the + * packet is large enough to contain the returned ip header. + * Only then can we do the check to see if 64 bits of packet + * data have been returned, since we need to check the returned + * ip header length. + */ +#define ICMP_MINLEN 8 /* abs minimum */ +#define ICMP_EXTD_MINLEN (156 - sizeof (struct ip)) /* draft-bonica-internet-icmp-08 */ +#define ICMP_TSLEN (8 + 3 * sizeof (uint32_t)) /* timestamp */ +#define ICMP_MASKLEN 12 /* address mask */ +#define ICMP_ADVLENMIN (8 + sizeof (struct ip) + 8) /* min */ +#define ICMP_ADVLEN(p) (8 + (IP_HL(&(p)->icmp_ip) << 2) + 8) + /* N.B.: must separately check that ip_hl >= 5 */ + +/* + * Definition of type and code field values. + */ +#define ICMP_ECHOREPLY 0 /* echo reply */ +#define ICMP_UNREACH 3 /* dest unreachable, codes: */ +#define ICMP_UNREACH_NET 0 /* bad net */ +#define ICMP_UNREACH_HOST 1 /* bad host */ +#define ICMP_UNREACH_PROTOCOL 2 /* bad protocol */ +#define ICMP_UNREACH_PORT 3 /* bad port */ +#define ICMP_UNREACH_NEEDFRAG 4 /* IP_DF caused drop */ +#define ICMP_UNREACH_SRCFAIL 5 /* src route failed */ +#define ICMP_UNREACH_NET_UNKNOWN 6 /* unknown net */ +#define ICMP_UNREACH_HOST_UNKNOWN 7 /* unknown host */ +#define ICMP_UNREACH_ISOLATED 8 /* src host isolated */ +#define ICMP_UNREACH_NET_PROHIB 9 /* prohibited access */ +#define ICMP_UNREACH_HOST_PROHIB 10 /* ditto */ +#define ICMP_UNREACH_TOSNET 11 /* bad tos for net */ +#define ICMP_UNREACH_TOSHOST 12 /* bad tos for host */ +#define ICMP_SOURCEQUENCH 4 /* packet lost, slow down */ +#define ICMP_REDIRECT 5 /* shorter route, codes: */ +#define ICMP_REDIRECT_NET 0 /* for network */ +#define ICMP_REDIRECT_HOST 1 /* for host */ +#define ICMP_REDIRECT_TOSNET 2 /* for tos and net */ +#define ICMP_REDIRECT_TOSHOST 3 /* for tos and host */ +#define ICMP_ECHO 8 /* echo service */ +#define ICMP_ROUTERADVERT 9 /* router advertisement */ +#define ICMP_ROUTERSOLICIT 10 /* router solicitation */ +#define ICMP_TIMXCEED 11 /* time exceeded, code: */ +#define ICMP_TIMXCEED_INTRANS 0 /* ttl==0 in transit */ +#define ICMP_TIMXCEED_REASS 1 /* ttl==0 in reass */ +#define ICMP_PARAMPROB 12 /* ip header bad */ +#define ICMP_PARAMPROB_OPTABSENT 1 /* req. opt. absent */ +#define ICMP_TSTAMP 13 /* timestamp request */ +#define ICMP_TSTAMPREPLY 14 /* timestamp reply */ +#define ICMP_IREQ 15 /* information request */ +#define ICMP_IREQREPLY 16 /* information reply */ +#define ICMP_MASKREQ 17 /* address mask request */ +#define ICMP_MASKREPLY 18 /* address mask reply */ + +#define ICMP_MAXTYPE 18 + +#define ICMP_ERRTYPE(type) \ + ((type) == ICMP_UNREACH || (type) == ICMP_SOURCEQUENCH || \ + (type) == ICMP_REDIRECT || (type) == ICMP_TIMXCEED || \ + (type) == ICMP_PARAMPROB) +#define ICMP_MULTIPART_EXT_TYPE(type) \ + ((type) == ICMP_UNREACH || \ + (type) == ICMP_TIMXCEED || \ + (type) == ICMP_PARAMPROB) +/* rfc1700 */ +#ifndef ICMP_UNREACH_NET_UNKNOWN +#define ICMP_UNREACH_NET_UNKNOWN 6 /* destination net unknown */ +#endif +#ifndef ICMP_UNREACH_HOST_UNKNOWN +#define ICMP_UNREACH_HOST_UNKNOWN 7 /* destination host unknown */ +#endif +#ifndef ICMP_UNREACH_ISOLATED +#define ICMP_UNREACH_ISOLATED 8 /* source host isolated */ +#endif +#ifndef ICMP_UNREACH_NET_PROHIB +#define ICMP_UNREACH_NET_PROHIB 9 /* admin prohibited net */ +#endif +#ifndef ICMP_UNREACH_HOST_PROHIB +#define ICMP_UNREACH_HOST_PROHIB 10 /* admin prohibited host */ +#endif +#ifndef ICMP_UNREACH_TOSNET +#define ICMP_UNREACH_TOSNET 11 /* tos prohibited net */ +#endif +#ifndef ICMP_UNREACH_TOSHOST +#define ICMP_UNREACH_TOSHOST 12 /* tos prohibited host */ +#endif + +/* rfc1716 */ +#ifndef ICMP_UNREACH_FILTER_PROHIB +#define ICMP_UNREACH_FILTER_PROHIB 13 /* admin prohibited filter */ +#endif +#ifndef ICMP_UNREACH_HOST_PRECEDENCE +#define ICMP_UNREACH_HOST_PRECEDENCE 14 /* host precedence violation */ +#endif +#ifndef ICMP_UNREACH_PRECEDENCE_CUTOFF +#define ICMP_UNREACH_PRECEDENCE_CUTOFF 15 /* precedence cutoff */ +#endif + +/* Most of the icmp types */ +static const struct tok icmp2str[] = { + { ICMP_ECHOREPLY, "echo reply" }, + { ICMP_SOURCEQUENCH, "source quench" }, + { ICMP_ECHO, "echo request" }, + { ICMP_ROUTERSOLICIT, "router solicitation" }, + { ICMP_TSTAMP, "time stamp request" }, + { ICMP_TSTAMPREPLY, "time stamp reply" }, + { ICMP_IREQ, "information request" }, + { ICMP_IREQREPLY, "information reply" }, + { ICMP_MASKREQ, "address mask request" }, + { 0, NULL } +}; + +/* rfc1191 */ +struct mtu_discovery { + nd_uint16_t unused; + nd_uint16_t nexthopmtu; +}; + +/* rfc1256 */ +struct ih_rdiscovery { + nd_uint8_t ird_addrnum; + nd_uint8_t ird_addrsiz; + nd_uint16_t ird_lifetime; +}; + +struct id_rdiscovery { + nd_uint32_t ird_addr; + nd_uint32_t ird_pref; +}; + +/* + * RFC 4884 - Extended ICMP to Support Multi-Part Messages + * + * This is a general extension mechanism, based on the mechanism + * in draft-bonica-icmp-mpls-02 ICMP Extensions for MultiProtocol + * Label Switching. + * + * The Destination Unreachable, Time Exceeded + * and Parameter Problem messages are slightly changed as per + * the above RFC. A new Length field gets added to give + * the caller an idea about the length of the piggybacked + * IP packet before the extension header starts. + * + * The Length field represents length of the padded "original datagram" + * field measured in 32-bit words. + * + * 0 1 2 3 + * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Type | Code | Checksum | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | unused | Length | unused | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | Internet Header + leading octets of original datagram | + * | | + * | // | + * | | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + */ + +struct icmp_ext_t { + nd_uint8_t icmp_type; + nd_uint8_t icmp_code; + nd_uint16_t icmp_checksum; + nd_byte icmp_reserved; + nd_uint8_t icmp_length; + nd_byte icmp_reserved2[2]; + nd_byte icmp_ext_legacy_header[128]; /* extension header starts 128 bytes after ICMP header */ + nd_byte icmp_ext_version_res[2]; + nd_uint16_t icmp_ext_checksum; + nd_byte icmp_ext_data[1]; +}; + +/* + * Extract version from the first octet of icmp_ext_version_res. + */ +#define ICMP_EXT_EXTRACT_VERSION(x) (((x)&0xf0)>>4) + +/* + * Current version. + */ +#define ICMP_EXT_VERSION 2 + +/* + * Extension object class numbers. + * + * Class 1 dates back to draft-bonica-icmp-mpls-02. + */ + +/* rfc4950 */ +#define MPLS_STACK_ENTRY_OBJECT_CLASS 1 + +struct icmp_multipart_ext_object_header_t { + nd_uint16_t length; + nd_uint8_t class_num; + nd_uint8_t ctype; +}; + +static const struct tok icmp_multipart_ext_obj_values[] = { + { 1, "MPLS Stack Entry" }, + { 2, "Interface Identification" }, + { 0, NULL} +}; + +/* prototypes */ +const char *icmp_tstamp_print(u_int); + +/* print the milliseconds since midnight UTC */ +const char * +icmp_tstamp_print(u_int tstamp) +{ + u_int msec,sec,min,hrs; + + static char buf[64]; + + msec = tstamp % 1000; + sec = tstamp / 1000; + min = sec / 60; sec -= min * 60; + hrs = min / 60; min -= hrs * 60; + snprintf(buf, sizeof(buf), "%02u:%02u:%02u.%03u",hrs,min,sec,msec); + return buf; +} + +void +icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *bp2, + int fragmented) +{ + char *cp; + const struct icmp *dp; + uint8_t icmp_type, icmp_code; + const struct icmp_ext_t *ext_dp; + const struct ip *ip; + const char *str; + const struct ip *oip; + uint8_t ip_proto; + const struct udphdr *ouh; + const uint8_t *obj_tptr; + uint32_t raw_label; + const struct icmp_multipart_ext_object_header_t *icmp_multipart_ext_object_header; + u_int hlen, mtu, obj_tlen, obj_class_num, obj_ctype; + uint16_t dport; + char buf[MAXHOSTNAMELEN + 100]; + struct cksum_vec vec[1]; + + ndo->ndo_protocol = "icmp"; + dp = (const struct icmp *)bp; + ext_dp = (const struct icmp_ext_t *)bp; + ip = (const struct ip *)bp2; + str = buf; + + icmp_type = GET_U_1(dp->icmp_type); + icmp_code = GET_U_1(dp->icmp_code); + switch (icmp_type) { + + case ICMP_ECHO: + case ICMP_ECHOREPLY: + (void)snprintf(buf, sizeof(buf), "echo %s, id %u, seq %u", + icmp_type == ICMP_ECHO ? + "request" : "reply", + GET_BE_U_2(dp->icmp_id), + GET_BE_U_2(dp->icmp_seq)); + break; + + case ICMP_UNREACH: + switch (icmp_code) { + + case ICMP_UNREACH_NET: + (void)snprintf(buf, sizeof(buf), + "net %s unreachable", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); + break; + + case ICMP_UNREACH_HOST: + (void)snprintf(buf, sizeof(buf), + "host %s unreachable", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); + break; + + case ICMP_UNREACH_PROTOCOL: + (void)snprintf(buf, sizeof(buf), + "%s protocol %u unreachable", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst), + GET_U_1(dp->icmp_ip.ip_p)); + break; + + case ICMP_UNREACH_PORT: + ND_TCHECK_1(dp->icmp_ip.ip_p); + oip = &dp->icmp_ip; + hlen = IP_HL(oip) * 4; + ouh = (const struct udphdr *)(((const u_char *)oip) + hlen); + dport = GET_BE_U_2(ouh->uh_dport); + ip_proto = GET_U_1(oip->ip_p); + switch (ip_proto) { + + case IPPROTO_TCP: + (void)snprintf(buf, sizeof(buf), + "%s tcp port %s unreachable", + GET_IPADDR_STRING(oip->ip_dst), + tcpport_string(ndo, dport)); + break; + + case IPPROTO_UDP: + (void)snprintf(buf, sizeof(buf), + "%s udp port %s unreachable", + GET_IPADDR_STRING(oip->ip_dst), + udpport_string(ndo, dport)); + break; + + default: + (void)snprintf(buf, sizeof(buf), + "%s protocol %u port %u unreachable", + GET_IPADDR_STRING(oip->ip_dst), + ip_proto, dport); + break; + } + break; + + case ICMP_UNREACH_NEEDFRAG: + { + const struct mtu_discovery *mp; + mp = (const struct mtu_discovery *)(const u_char *)&dp->icmp_void; + mtu = GET_BE_U_2(mp->nexthopmtu); + if (mtu) { + (void)snprintf(buf, sizeof(buf), + "%s unreachable - need to frag (mtu %u)", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst), mtu); + } else { + (void)snprintf(buf, sizeof(buf), + "%s unreachable - need to frag", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); + } + } + break; + + case ICMP_UNREACH_SRCFAIL: + (void)snprintf(buf, sizeof(buf), + "%s unreachable - source route failed", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); + break; + + case ICMP_UNREACH_NET_UNKNOWN: + (void)snprintf(buf, sizeof(buf), + "net %s unreachable - unknown", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); + break; + + case ICMP_UNREACH_HOST_UNKNOWN: + (void)snprintf(buf, sizeof(buf), + "host %s unreachable - unknown", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); + break; + + case ICMP_UNREACH_ISOLATED: + (void)snprintf(buf, sizeof(buf), + "%s unreachable - source host isolated", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); + break; + + case ICMP_UNREACH_NET_PROHIB: + (void)snprintf(buf, sizeof(buf), + "net %s unreachable - admin prohibited", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); + break; + + case ICMP_UNREACH_HOST_PROHIB: + (void)snprintf(buf, sizeof(buf), + "host %s unreachable - admin prohibited", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); + break; + + case ICMP_UNREACH_TOSNET: + (void)snprintf(buf, sizeof(buf), + "net %s unreachable - tos prohibited", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); + break; + + case ICMP_UNREACH_TOSHOST: + (void)snprintf(buf, sizeof(buf), + "host %s unreachable - tos prohibited", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); + break; + + case ICMP_UNREACH_FILTER_PROHIB: + (void)snprintf(buf, sizeof(buf), + "host %s unreachable - admin prohibited filter", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); + break; + + case ICMP_UNREACH_HOST_PRECEDENCE: + (void)snprintf(buf, sizeof(buf), + "host %s unreachable - host precedence violation", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); + break; + + case ICMP_UNREACH_PRECEDENCE_CUTOFF: + (void)snprintf(buf, sizeof(buf), + "host %s unreachable - precedence cutoff", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst)); + break; + + default: + (void)snprintf(buf, sizeof(buf), + "%s unreachable - #%u", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst), + icmp_code); + break; + } + break; + + case ICMP_REDIRECT: + switch (icmp_code) { + + case ICMP_REDIRECT_NET: + (void)snprintf(buf, sizeof(buf), + "redirect %s to net %s", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst), + GET_IPADDR_STRING(dp->icmp_gwaddr)); + break; + + case ICMP_REDIRECT_HOST: + (void)snprintf(buf, sizeof(buf), + "redirect %s to host %s", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst), + GET_IPADDR_STRING(dp->icmp_gwaddr)); + break; + + case ICMP_REDIRECT_TOSNET: + (void)snprintf(buf, sizeof(buf), + "redirect-tos %s to net %s", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst), + GET_IPADDR_STRING(dp->icmp_gwaddr)); + break; + + case ICMP_REDIRECT_TOSHOST: + (void)snprintf(buf, sizeof(buf), + "redirect-tos %s to host %s", + GET_IPADDR_STRING(dp->icmp_ip.ip_dst), + GET_IPADDR_STRING(dp->icmp_gwaddr)); + break; + + default: + (void)snprintf(buf, sizeof(buf), + "redirect-#%u %s to %s", icmp_code, + GET_IPADDR_STRING(dp->icmp_ip.ip_dst), + GET_IPADDR_STRING(dp->icmp_gwaddr)); + break; + } + break; + + case ICMP_ROUTERADVERT: + { + const struct ih_rdiscovery *ihp; + const struct id_rdiscovery *idp; + u_int lifetime, num, size; + + (void)snprintf(buf, sizeof(buf), "router advertisement"); + cp = buf + strlen(buf); + + ihp = (const struct ih_rdiscovery *)&dp->icmp_void; + ND_TCHECK_SIZE(ihp); + (void)strncpy(cp, " lifetime ", sizeof(buf) - (cp - buf)); + cp = buf + strlen(buf); + lifetime = GET_BE_U_2(ihp->ird_lifetime); + if (lifetime < 60) { + (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u", + lifetime); + } else if (lifetime < 60 * 60) { + (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u:%02u", + lifetime / 60, lifetime % 60); + } else { + (void)snprintf(cp, sizeof(buf) - (cp - buf), + "%u:%02u:%02u", + lifetime / 3600, + (lifetime % 3600) / 60, + lifetime % 60); + } + cp = buf + strlen(buf); + + num = GET_U_1(ihp->ird_addrnum); + (void)snprintf(cp, sizeof(buf) - (cp - buf), " %u:", num); + cp = buf + strlen(buf); + + size = GET_U_1(ihp->ird_addrsiz); + if (size != 2) { + (void)snprintf(cp, sizeof(buf) - (cp - buf), + " [size %u]", size); + break; + } + idp = (const struct id_rdiscovery *)&dp->icmp_data; + while (num > 0) { + ND_TCHECK_SIZE(idp); + (void)snprintf(cp, sizeof(buf) - (cp - buf), " {%s %u}", + GET_IPADDR_STRING(idp->ird_addr), + GET_BE_U_4(idp->ird_pref)); + cp = buf + strlen(buf); + ++idp; + num--; + } + } + break; + + case ICMP_TIMXCEED: + ND_TCHECK_4(dp->icmp_ip.ip_dst); + switch (icmp_code) { + + case ICMP_TIMXCEED_INTRANS: + str = "time exceeded in-transit"; + break; + + case ICMP_TIMXCEED_REASS: + str = "ip reassembly time exceeded"; + break; + + default: + (void)snprintf(buf, sizeof(buf), "time exceeded-#%u", + icmp_code); + break; + } + break; + + case ICMP_PARAMPROB: + if (icmp_code) + (void)snprintf(buf, sizeof(buf), + "parameter problem - code %u", icmp_code); + else { + (void)snprintf(buf, sizeof(buf), + "parameter problem - octet %u", + GET_U_1(dp->icmp_pptr)); + } + break; + + case ICMP_MASKREPLY: + (void)snprintf(buf, sizeof(buf), "address mask is 0x%08x", + GET_BE_U_4(dp->icmp_mask)); + break; + + case ICMP_TSTAMP: + (void)snprintf(buf, sizeof(buf), + "time stamp query id %u seq %u", + GET_BE_U_2(dp->icmp_id), + GET_BE_U_2(dp->icmp_seq)); + break; + + case ICMP_TSTAMPREPLY: + ND_TCHECK_4(dp->icmp_ttime); + (void)snprintf(buf, sizeof(buf), + "time stamp reply id %u seq %u: org %s", + GET_BE_U_2(dp->icmp_id), + GET_BE_U_2(dp->icmp_seq), + icmp_tstamp_print(GET_BE_U_4(dp->icmp_otime))); + + (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", recv %s", + icmp_tstamp_print(GET_BE_U_4(dp->icmp_rtime))); + (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", xmit %s", + icmp_tstamp_print(GET_BE_U_4(dp->icmp_ttime))); + break; + + default: + str = tok2str(icmp2str, "type-#%u", icmp_type); + break; + } + ND_PRINT("ICMP %s, length %u", str, plen); + if (ndo->ndo_vflag && !fragmented) { /* don't attempt checksumming if this is a frag */ + if (ND_TTEST_LEN(bp, plen)) { + uint16_t sum; + + vec[0].ptr = (const uint8_t *)(const void *)dp; + vec[0].len = plen; + sum = in_cksum(vec, 1); + if (sum != 0) { + uint16_t icmp_sum = GET_BE_U_2(dp->icmp_cksum); + ND_PRINT(" (wrong icmp cksum %x (->%x)!)", + icmp_sum, + in_cksum_shouldbe(icmp_sum, sum)); + } + } + } + + /* + * print the remnants of the IP packet. + * save the snaplength as this may get overridden in the IP printer. + */ + if (ndo->ndo_vflag >= 1 && ICMP_ERRTYPE(icmp_type)) { + const u_char *snapend_save; + + bp += 8; + ND_PRINT("\n\t"); + ip = (const struct ip *)bp; + snapend_save = ndo->ndo_snapend; + /* + * Update the snapend because extensions (MPLS, ...) may be + * present after the IP packet. In this case the current + * (outer) packet's snapend is not what ip_print() needs to + * decode an IP packet nested in the middle of an ICMP payload. + * + * This prevents that, in ip_print(), for the nested IP packet, + * the remaining length < remaining caplen. + */ + ndo->ndo_snapend = ND_MIN(bp + GET_BE_U_2(ip->ip_len), + ndo->ndo_snapend); + ip_print(ndo, bp, GET_BE_U_2(ip->ip_len)); + ndo->ndo_snapend = snapend_save; + } + + /* ndo_protocol reassignment after ip_print() call */ + ndo->ndo_protocol = "icmp"; + + /* + * Attempt to decode multi-part message extensions (rfc4884) only for some ICMP types. + */ + if (ndo->ndo_vflag >= 1 && plen > ICMP_EXTD_MINLEN && ICMP_MULTIPART_EXT_TYPE(icmp_type)) { + + ND_TCHECK_SIZE(ext_dp); + + /* + * Check first if the multi-part extension header shows a non-zero length. + * If the length field is not set then silently verify the checksum + * to check if an extension header is present. This is expedient, + * however not all implementations set the length field proper. + */ + if (GET_U_1(ext_dp->icmp_length) == 0 && + ND_TTEST_LEN(ext_dp->icmp_ext_version_res, plen - ICMP_EXTD_MINLEN)) { + vec[0].ptr = (const uint8_t *)(const void *)&ext_dp->icmp_ext_version_res; + vec[0].len = plen - ICMP_EXTD_MINLEN; + if (in_cksum(vec, 1)) { + return; + } + } + + ND_PRINT("\n\tICMP Multi-Part extension v%u", + ICMP_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res))); + + /* + * Sanity checking of the header. + */ + if (ICMP_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)) != + ICMP_EXT_VERSION) { + ND_PRINT(" packet not supported"); + return; + } + + hlen = plen - ICMP_EXTD_MINLEN; + if (ND_TTEST_LEN(ext_dp->icmp_ext_version_res, hlen)) { + vec[0].ptr = (const uint8_t *)(const void *)&ext_dp->icmp_ext_version_res; + vec[0].len = hlen; + ND_PRINT(", checksum 0x%04x (%scorrect), length %u", + GET_BE_U_2(ext_dp->icmp_ext_checksum), + in_cksum(vec, 1) ? "in" : "", + hlen); + } + + hlen -= 4; /* subtract common header size */ + obj_tptr = (const uint8_t *)ext_dp->icmp_ext_data; + + while (hlen > sizeof(struct icmp_multipart_ext_object_header_t)) { + + icmp_multipart_ext_object_header = (const struct icmp_multipart_ext_object_header_t *)obj_tptr; + ND_TCHECK_SIZE(icmp_multipart_ext_object_header); + obj_tlen = GET_BE_U_2(icmp_multipart_ext_object_header->length); + obj_class_num = GET_U_1(icmp_multipart_ext_object_header->class_num); + obj_ctype = GET_U_1(icmp_multipart_ext_object_header->ctype); + obj_tptr += sizeof(struct icmp_multipart_ext_object_header_t); + + ND_PRINT("\n\t %s Object (%u), Class-Type: %u, length %u", + tok2str(icmp_multipart_ext_obj_values,"unknown",obj_class_num), + obj_class_num, + obj_ctype, + obj_tlen); + + hlen-=sizeof(struct icmp_multipart_ext_object_header_t); /* length field includes tlv header */ + + /* infinite loop protection */ + if ((obj_class_num == 0) || + (obj_tlen < sizeof(struct icmp_multipart_ext_object_header_t))) { + return; + } + obj_tlen-=sizeof(struct icmp_multipart_ext_object_header_t); + + switch (obj_class_num) { + case MPLS_STACK_ENTRY_OBJECT_CLASS: + switch(obj_ctype) { + case 1: + raw_label = GET_BE_U_4(obj_tptr); + ND_PRINT("\n\t label %u, tc %u", MPLS_LABEL(raw_label), MPLS_TC(raw_label)); + if (MPLS_STACK(raw_label)) + ND_PRINT(", [S]"); + ND_PRINT(", ttl %u", MPLS_TTL(raw_label)); + break; + default: + print_unknown_data(ndo, obj_tptr, "\n\t ", obj_tlen); + } + break; + + default: + print_unknown_data(ndo, obj_tptr, "\n\t ", obj_tlen); + break; + } + if (hlen < obj_tlen) + break; + hlen -= obj_tlen; + obj_tptr += obj_tlen; + } + } + + return; +trunc: + nd_print_trunc(ndo); +} |