* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
-#ifndef lint
-static const char rcsid[] =
- "@(#) $Header: /tcpdump/master/tcpdump/print-icmp.c,v 1.47 2000-06-10 13:41:19 assar Exp $ (LBL)";
-#endif
+/* \summary: Internet Control Message Protocol (ICMP) printer */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
-#include <sys/param.h>
-#include <sys/time.h>
-#include <sys/socket.h>
-
-#if __STDC__
-struct mbuf;
-struct rtentry;
-#endif
-#include <net/if.h>
-
-#include <netinet/in.h>
-#include <netinet/if_ether.h>
-#include <netinet/in_systm.h>
-#include <netinet/ip.h>
-#include <netinet/ip_icmp.h>
-#include <netinet/ip_var.h>
-#include <netinet/udp.h>
-#include <netinet/udp_var.h>
-#include <netinet/tcp.h>
+#include <netdissect-stdinc.h>
#include <stdio.h>
#include <string.h>
-#include "interface.h"
+#include "netdissect.h"
#include "addrtoname.h"
-#include "extract.h" /* must come after interface.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 {
+ uint8_t icmp_type; /* type of message, see below */
+ uint8_t icmp_code; /* type sub code */
+ uint16_t icmp_cksum; /* ones complement cksum of struct */
+ union {
+ uint8_t ih_pptr; /* ICMP_PARAMPROB */
+ struct in_addr ih_gwaddr; /* ICMP_REDIRECT */
+ struct ih_idseq {
+ uint16_t icd_id;
+ uint16_t icd_seq;
+ } ih_idseq;
+ 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 {
+ uint32_t its_otime;
+ uint32_t its_rtime;
+ uint32_t its_ttime;
+ } id_ts;
+ struct id_ip {
+ struct ip idi_ip;
+ /* options and then 64 bits of data */
+ } id_ip;
+ uint32_t id_mask;
+ uint8_t 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_MPLS_EXT_EXTRACT_VERSION(x) (((x)&0xf0)>>4)
+#define ICMP_MPLS_EXT_VERSION 2
+
+/*
+ * Lower bounds on packet lengths for various types.
+ * For the error advice packets must first insure that the
+ * packet is large enought 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_MPLS_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 */
#define ICMP_UNREACH_PRECEDENCE_CUTOFF 15 /* precedence cutoff */
#endif
-/* rfc1256 */
-#ifndef ICMP_ROUTERADVERT
-#define ICMP_ROUTERADVERT 9 /* router advertisement */
-#endif
-#ifndef ICMP_ROUTERSOLICIT
-#define ICMP_ROUTERSOLICIT 10 /* router solicitation */
-#endif
-
/* Most of the icmp types */
-static struct tok icmp2str[] = {
+static const struct tok icmp2str[] = {
{ ICMP_ECHOREPLY, "echo reply" },
{ ICMP_SOURCEQUENCH, "source quench" },
{ ICMP_ECHO, "echo request" },
};
/* Formats for most of the ICMP_UNREACH codes */
-static struct tok unreach2str[] = {
+static const struct tok unreach2str[] = {
{ ICMP_UNREACH_NET, "net %s unreachable" },
{ ICMP_UNREACH_HOST, "host %s unreachable" },
{ ICMP_UNREACH_SRCFAIL,
};
/* Formats for the ICMP_REDIRECT codes */
-static struct tok type2str[] = {
+static const struct tok type2str[] = {
{ ICMP_REDIRECT_NET, "redirect %s to net %s" },
{ ICMP_REDIRECT_HOST, "redirect %s to host %s" },
{ ICMP_REDIRECT_TOSNET, "redirect-tos %s to net %s" },
- { ICMP_REDIRECT_TOSHOST, "redirect-tos %s to net %s" },
+ { ICMP_REDIRECT_TOSHOST, "redirect-tos %s to host %s" },
{ 0, NULL }
};
/* rfc1191 */
struct mtu_discovery {
- short unused;
- short nexthopmtu;
+ uint16_t unused;
+ uint16_t nexthopmtu;
};
/* rfc1256 */
struct ih_rdiscovery {
- u_char ird_addrnum;
- u_char ird_addrsiz;
- u_short ird_lifetime;
+ uint8_t ird_addrnum;
+ uint8_t ird_addrsiz;
+ uint16_t ird_lifetime;
};
struct id_rdiscovery {
- u_int32_t ird_addr;
- u_int32_t ird_pref;
+ uint32_t ird_addr;
+ uint32_t ird_pref;
};
+/*
+ * draft-bonica-internet-icmp-08
+ *
+ * The Destination Unreachable, Time Exceeded
+ * and Parameter Problem messages are slighly changed as per
+ * the above draft. A new Length field gets added to give
+ * the caller an idea about the length of the piggypacked
+ * IP packet before the MPLS 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 {
+ uint8_t icmp_type;
+ uint8_t icmp_code;
+ uint8_t icmp_checksum[2];
+ uint8_t icmp_reserved;
+ uint8_t icmp_length;
+ uint8_t icmp_reserved2[2];
+ uint8_t icmp_ext_legacy_header[128]; /* extension header starts 128 bytes after ICMP header */
+ uint8_t icmp_ext_version_res[2];
+ uint8_t icmp_ext_checksum[2];
+ uint8_t icmp_ext_data[1];
+};
+
+struct icmp_mpls_ext_object_header_t {
+ uint8_t length[2];
+ uint8_t class_num;
+ uint8_t ctype;
+};
+
+static const struct tok icmp_mpls_ext_obj_values[] = {
+ { 1, "MPLS Stack Entry" },
+ { 2, "Extended Payload" },
+ { 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(register const u_char *bp, u_int plen, register const u_char *bp2)
+icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *bp2,
+ int fragmented)
{
- register char *cp;
- register const struct icmp *dp;
- register const struct ip *ip;
- register const char *str, *fmt;
- register const struct ip *oip;
- register const struct udphdr *ouh;
- register u_int hlen, dport, mtu;
- char buf[256];
-
- dp = (struct icmp *)bp;
- ip = (struct ip *)bp2;
+ char *cp;
+ const struct icmp *dp;
+ const struct icmp_ext_t *ext_dp;
+ const struct ip *ip;
+ const char *str, *fmt;
+ const struct ip *oip;
+ const struct udphdr *ouh;
+ const uint8_t *obj_tptr;
+ uint32_t raw_label;
+ const u_char *snapend_save;
+ const struct icmp_mpls_ext_object_header_t *icmp_mpls_ext_object_header;
+ u_int hlen, dport, mtu, obj_tlen, obj_class_num, obj_ctype;
+ char buf[MAXHOSTNAMELEN + 100];
+ struct cksum_vec vec[1];
+
+ dp = (const struct icmp *)bp;
+ ext_dp = (const struct icmp_ext_t *)bp;
+ ip = (const struct ip *)bp2;
str = buf;
-#if 0
- (void)printf("%s > %s: ",
- ipaddr_string(&ip->ip_src),
- ipaddr_string(&ip->ip_dst));
-#endif
-
- TCHECK(dp->icmp_code);
+ ND_TCHECK(dp->icmp_code);
switch (dp->icmp_type) {
+ case ICMP_ECHO:
+ case ICMP_ECHOREPLY:
+ ND_TCHECK(dp->icmp_seq);
+ (void)snprintf(buf, sizeof(buf), "echo %s, id %u, seq %u",
+ dp->icmp_type == ICMP_ECHO ?
+ "request" : "reply",
+ EXTRACT_16BITS(&dp->icmp_id),
+ EXTRACT_16BITS(&dp->icmp_seq));
+ break;
+
case ICMP_UNREACH:
- TCHECK(dp->icmp_ip.ip_dst);
+ ND_TCHECK(dp->icmp_ip.ip_dst);
switch (dp->icmp_code) {
case ICMP_UNREACH_PROTOCOL:
- TCHECK(dp->icmp_ip.ip_p);
+ ND_TCHECK(dp->icmp_ip.ip_p);
(void)snprintf(buf, sizeof(buf),
"%s protocol %d unreachable",
- ipaddr_string(&dp->icmp_ip.ip_dst),
+ ipaddr_string(ndo, &dp->icmp_ip.ip_dst),
dp->icmp_ip.ip_p);
break;
case ICMP_UNREACH_PORT:
- TCHECK(dp->icmp_ip.ip_p);
+ ND_TCHECK(dp->icmp_ip.ip_p);
oip = &dp->icmp_ip;
- hlen = oip->ip_hl * 4;
- ouh = (struct udphdr *)(((u_char *)oip) + hlen);
- dport = ntohs(ouh->uh_dport);
+ hlen = IP_HL(oip) * 4;
+ ouh = (const struct udphdr *)(((const u_char *)oip) + hlen);
+ ND_TCHECK(ouh->uh_dport);
+ dport = EXTRACT_16BITS(&ouh->uh_dport);
switch (oip->ip_p) {
case IPPROTO_TCP:
(void)snprintf(buf, sizeof(buf),
"%s tcp port %s unreachable",
- ipaddr_string(&oip->ip_dst),
- tcpport_string(dport));
+ ipaddr_string(ndo, &oip->ip_dst),
+ tcpport_string(ndo, dport));
break;
case IPPROTO_UDP:
(void)snprintf(buf, sizeof(buf),
"%s udp port %s unreachable",
- ipaddr_string(&oip->ip_dst),
- udpport_string(dport));
+ ipaddr_string(ndo, &oip->ip_dst),
+ udpport_string(ndo, dport));
break;
default:
(void)snprintf(buf, sizeof(buf),
"%s protocol %d port %d unreachable",
- ipaddr_string(&oip->ip_dst),
+ ipaddr_string(ndo, &oip->ip_dst),
oip->ip_p, dport);
break;
}
case ICMP_UNREACH_NEEDFRAG:
{
register const struct mtu_discovery *mp;
- mp = (struct mtu_discovery *)&dp->icmp_void;
- mtu = EXTRACT_16BITS(&mp->nexthopmtu);
- if (mtu) {
+ mp = (const struct mtu_discovery *)(const u_char *)&dp->icmp_void;
+ mtu = EXTRACT_16BITS(&mp->nexthopmtu);
+ if (mtu) {
(void)snprintf(buf, sizeof(buf),
"%s unreachable - need to frag (mtu %d)",
- ipaddr_string(&dp->icmp_ip.ip_dst), mtu);
- } else {
+ ipaddr_string(ndo, &dp->icmp_ip.ip_dst), mtu);
+ } else {
(void)snprintf(buf, sizeof(buf),
"%s unreachable - need to frag",
- ipaddr_string(&dp->icmp_ip.ip_dst));
+ ipaddr_string(ndo, &dp->icmp_ip.ip_dst));
}
}
break;
fmt = tok2str(unreach2str, "#%d %%s unreachable",
dp->icmp_code);
(void)snprintf(buf, sizeof(buf), fmt,
- ipaddr_string(&dp->icmp_ip.ip_dst));
+ ipaddr_string(ndo, &dp->icmp_ip.ip_dst));
break;
}
break;
case ICMP_REDIRECT:
- TCHECK(dp->icmp_ip.ip_dst);
+ ND_TCHECK(dp->icmp_ip.ip_dst);
fmt = tok2str(type2str, "redirect-#%d %%s to net %%s",
dp->icmp_code);
(void)snprintf(buf, sizeof(buf), fmt,
- ipaddr_string(&dp->icmp_ip.ip_dst),
- ipaddr_string(&dp->icmp_gwaddr));
+ ipaddr_string(ndo, &dp->icmp_ip.ip_dst),
+ ipaddr_string(ndo, &dp->icmp_gwaddr));
break;
case ICMP_ROUTERADVERT:
(void)snprintf(buf, sizeof(buf), "router advertisement");
cp = buf + strlen(buf);
- ihp = (struct ih_rdiscovery *)&dp->icmp_void;
- TCHECK(*ihp);
+ ihp = (const struct ih_rdiscovery *)&dp->icmp_void;
+ ND_TCHECK(*ihp);
(void)strncpy(cp, " lifetime ", sizeof(buf) - (cp - buf));
cp = buf + strlen(buf);
lifetime = EXTRACT_16BITS(&ihp->ird_lifetime);
" [size %d]", size);
break;
}
- idp = (struct id_rdiscovery *)&dp->icmp_data;
+ idp = (const struct id_rdiscovery *)&dp->icmp_data;
while (num-- > 0) {
- TCHECK(*idp);
+ ND_TCHECK(*idp);
(void)snprintf(cp, sizeof(buf) - (cp - buf), " {%s %u}",
- ipaddr_string(&idp->ird_addr),
+ ipaddr_string(ndo, &idp->ird_addr),
EXTRACT_32BITS(&idp->ird_pref));
cp = buf + strlen(buf);
++idp;
break;
case ICMP_TIMXCEED:
- TCHECK(dp->icmp_ip.ip_dst);
+ ND_TCHECK(dp->icmp_ip.ip_dst);
switch (dp->icmp_code) {
case ICMP_TIMXCEED_INTRANS:
(void)snprintf(buf, sizeof(buf),
"parameter problem - code %d", dp->icmp_code);
else {
- TCHECK(dp->icmp_pptr);
+ ND_TCHECK(dp->icmp_pptr);
(void)snprintf(buf, sizeof(buf),
"parameter problem - octet %d", dp->icmp_pptr);
}
break;
case ICMP_MASKREPLY:
- TCHECK(dp->icmp_mask);
+ ND_TCHECK(dp->icmp_mask);
(void)snprintf(buf, sizeof(buf), "address mask is 0x%08x",
- (unsigned)ntohl(dp->icmp_mask));
+ EXTRACT_32BITS(&dp->icmp_mask));
break;
case ICMP_TSTAMP:
- TCHECK(dp->icmp_seq);
- (void)sprintf(buf, "time stamp query id %u seq %u",
- (unsigned)ntohs(dp->icmp_id),
- (unsigned)ntohs(dp->icmp_seq));
+ ND_TCHECK(dp->icmp_seq);
+ (void)snprintf(buf, sizeof(buf),
+ "time stamp query id %u seq %u",
+ EXTRACT_16BITS(&dp->icmp_id),
+ EXTRACT_16BITS(&dp->icmp_seq));
break;
case ICMP_TSTAMPREPLY:
- TCHECK(dp->icmp_ttime);
- (void)sprintf(buf, "time stamp reply id %u seq %u : org 0x%lx recv 0x%lx xmit 0x%lx",
- (unsigned)ntohs(dp->icmp_id),
- (unsigned)ntohs(dp->icmp_seq),
- (unsigned long)ntohl(dp->icmp_otime),
- (unsigned long)ntohl(dp->icmp_rtime),
- (unsigned long)ntohl(dp->icmp_ttime));
- break;
+ ND_TCHECK(dp->icmp_ttime);
+ (void)snprintf(buf, sizeof(buf),
+ "time stamp reply id %u seq %u: org %s",
+ EXTRACT_16BITS(&dp->icmp_id),
+ EXTRACT_16BITS(&dp->icmp_seq),
+ icmp_tstamp_print(EXTRACT_32BITS(&dp->icmp_otime)));
+
+ (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", recv %s",
+ icmp_tstamp_print(EXTRACT_32BITS(&dp->icmp_rtime)));
+ (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", xmit %s",
+ icmp_tstamp_print(EXTRACT_32BITS(&dp->icmp_ttime)));
+ break;
default:
str = tok2str(icmp2str, "type-#%d", dp->icmp_type);
break;
}
- (void)printf("icmp: %s", str);
- if (vflag) {
- if (TTEST2(*bp, plen)) {
- if (in_cksum((u_short*)dp, plen, 0))
- printf(" (wrong icmp csum)");
+ ND_PRINT((ndo, "ICMP %s, length %u", str, plen));
+ if (ndo->ndo_vflag && !fragmented) { /* don't attempt checksumming if this is a frag */
+ uint16_t sum, icmp_sum;
+
+ if (ND_TTEST2(*bp, plen)) {
+ vec[0].ptr = (const uint8_t *)(const void *)dp;
+ vec[0].len = plen;
+ sum = in_cksum(vec, 1);
+ if (sum != 0) {
+ icmp_sum = EXTRACT_16BITS(&dp->icmp_cksum);
+ ND_PRINT((ndo, " (wrong icmp cksum %x (->%x)!)",
+ icmp_sum,
+ in_cksum_shouldbe(icmp_sum, sum)));
+ }
}
}
- if (vflag > 1 && !ICMP_INFOTYPE(dp->icmp_type)) {
- bp += 8;
- (void)printf(" for ");
- ip = (struct ip *)bp;
- snaplen = snapend - bp;
- ip_print(bp, ntohs(ip->ip_len));
- }
+
+ /*
+ * print the remnants of the IP packet.
+ * save the snaplength as this may get overidden in the IP printer.
+ */
+ if (ndo->ndo_vflag >= 1 && ICMP_ERRTYPE(dp->icmp_type)) {
+ bp += 8;
+ ND_PRINT((ndo, "\n\t"));
+ ip = (const struct ip *)bp;
+ snapend_save = ndo->ndo_snapend;
+ ip_print(ndo, bp, EXTRACT_16BITS(&ip->ip_len));
+ ndo->ndo_snapend = snapend_save;
+ }
+
+ /*
+ * Attempt to decode the MPLS extensions only for some ICMP types.
+ */
+ if (ndo->ndo_vflag >= 1 && plen > ICMP_EXTD_MINLEN && ICMP_MPLS_EXT_TYPE(dp->icmp_type)) {
+
+ ND_TCHECK(*ext_dp);
+
+ /*
+ * Check first if the mpls 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 (!ext_dp->icmp_length) {
+ 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((ndo, "\n\tMPLS extension v%u",
+ ICMP_MPLS_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res))));
+
+ /*
+ * Sanity checking of the header.
+ */
+ if (ICMP_MPLS_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)) !=
+ ICMP_MPLS_EXT_VERSION) {
+ ND_PRINT((ndo, " packet not supported"));
+ return;
+ }
+
+ hlen = plen - ICMP_EXTD_MINLEN;
+ vec[0].ptr = (const uint8_t *)(const void *)&ext_dp->icmp_ext_version_res;
+ vec[0].len = hlen;
+ ND_PRINT((ndo, ", checksum 0x%04x (%scorrect), length %u",
+ EXTRACT_16BITS(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_mpls_ext_object_header_t)) {
+
+ icmp_mpls_ext_object_header = (const struct icmp_mpls_ext_object_header_t *)obj_tptr;
+ ND_TCHECK(*icmp_mpls_ext_object_header);
+ obj_tlen = EXTRACT_16BITS(icmp_mpls_ext_object_header->length);
+ obj_class_num = icmp_mpls_ext_object_header->class_num;
+ obj_ctype = icmp_mpls_ext_object_header->ctype;
+ obj_tptr += sizeof(struct icmp_mpls_ext_object_header_t);
+
+ ND_PRINT((ndo, "\n\t %s Object (%u), Class-Type: %u, length %u",
+ tok2str(icmp_mpls_ext_obj_values,"unknown",obj_class_num),
+ obj_class_num,
+ obj_ctype,
+ obj_tlen));
+
+ hlen-=sizeof(struct icmp_mpls_ext_object_header_t); /* length field includes tlv header */
+
+ /* infinite loop protection */
+ if ((obj_class_num == 0) ||
+ (obj_tlen < sizeof(struct icmp_mpls_ext_object_header_t))) {
+ return;
+ }
+ obj_tlen-=sizeof(struct icmp_mpls_ext_object_header_t);
+
+ switch (obj_class_num) {
+ case 1:
+ switch(obj_ctype) {
+ case 1:
+ ND_TCHECK2(*obj_tptr, 4);
+ raw_label = EXTRACT_32BITS(obj_tptr);
+ ND_PRINT((ndo, "\n\t label %u, exp %u", MPLS_LABEL(raw_label), MPLS_EXP(raw_label)));
+ if (MPLS_STACK(raw_label))
+ ND_PRINT((ndo, ", [S]"));
+ ND_PRINT((ndo, ", ttl %u", MPLS_TTL(raw_label)));
+ break;
+ default:
+ print_unknown_data(ndo, obj_tptr, "\n\t ", obj_tlen);
+ }
+ break;
+
+ /*
+ * FIXME those are the defined objects that lack a decoder
+ * you are welcome to contribute code ;-)
+ */
+ case 2:
+ 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:
- fputs("[|icmp]", stdout);
+ ND_PRINT((ndo, "[|icmp]"));
}
+/*
+ * Local Variables:
+ * c-style: whitesmith
+ * c-basic-offset: 8
+ * End:
+ */
projects / tcpdump / blobdiff