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-rw-r--r--print-icmp.c797
1 files changed, 797 insertions, 0 deletions
diff --git a/print-icmp.c b/print-icmp.c
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--- /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);
+}