*/
#ifndef lint
-static const char rcsid[] =
- "@(#) $Header: /tcpdump/master/tcpdump/print-icmp.c,v 1.69 2002-08-01 08:53:08 risso Exp $ (LBL)";
+static const char rcsid[] _U_ =
+ "@(#) $Header: /tcpdump/master/tcpdump/print-icmp.c,v 1.87 2007-09-13 17:42:31 guy Exp $ (LBL)";
#endif
#ifdef HAVE_CONFIG_H
#include "ip.h"
#include "udp.h"
+#include "ipproto.h"
+#include "mpls.h"
/*
* Interface Control Message Protocol Definitions.
u_int16_t icd_seq;
} ih_idseq;
u_int32_t ih_void;
-
- /* ICMP_UNREACH_NEEDFRAG -- Path MTU Discovery (RFC1191) */
- struct ih_pmtu {
- u_int16_t ipm_void;
- u_int16_t ipm_nextmtu;
- } ih_pmtu;
} 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
union {
struct id_ts {
u_int32_t its_otime;
#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
* 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 (u_int32_t)) /* timestamp */
#define ICMP_MASKLEN 12 /* address mask */
#define ICMP_ADVLENMIN (8 + sizeof (struct ip) + 8) /* min */
(type) == ICMP_TSTAMP || (type) == ICMP_TSTAMPREPLY || \
(type) == ICMP_IREQ || (type) == ICMP_IREQREPLY || \
(type) == ICMP_MASKREQ || (type) == ICMP_MASKREPLY)
+#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 */
u_int32_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 {
+ u_int8_t icmp_type;
+ u_int8_t icmp_code;
+ u_int8_t icmp_checksum[2];
+ u_int8_t icmp_reserved;
+ u_int8_t icmp_length;
+ u_int8_t icmp_reserved2[2];
+ u_int8_t icmp_ext_legacy_header[128]; /* extension header starts 128 bytes after ICMP header */
+ u_int8_t icmp_ext_version_res[2];
+ u_int8_t icmp_ext_checksum[2];
+ u_int8_t icmp_ext_data[1];
+};
+
+struct icmp_mpls_ext_object_header_t {
+ u_int8_t length[2];
+ u_int8_t class_num;
+ u_int8_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(const u_char *bp, u_int plen, const u_char *bp2)
+icmp_print(const u_char *bp, u_int plen, const u_char *bp2, int fragmented)
{
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;
- u_int hlen, dport, mtu;
+ const u_int8_t *obj_tptr;
+ u_int32_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 = (struct icmp *)bp;
+ ext_dp = (struct icmp_ext_t *)bp;
ip = (struct ip *)bp2;
str = buf;
case ICMP_ECHO:
case ICMP_ECHOREPLY:
TCHECK(dp->icmp_seq);
- (void)snprintf(buf, sizeof(buf), "echo %s seq %u",
- dp->icmp_type == ICMP_ECHO ?
- "request" : "reply",
- (unsigned)ntohs(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:
oip = &dp->icmp_ip;
hlen = IP_HL(oip) * 4;
ouh = (struct udphdr *)(((u_char *)oip) + hlen);
- dport = ntohs(ouh->uh_dport);
+ TCHECK(ouh->uh_dport);
+ dport = EXTRACT_16BITS(&ouh->uh_dport);
switch (oip->ip_p) {
case IPPROTO_TCP:
case ICMP_UNREACH_NEEDFRAG:
{
register const struct mtu_discovery *mp;
- mp = (struct mtu_discovery *)&dp->icmp_void;
+ mp = (struct mtu_discovery *)(u_char *)&dp->icmp_void;
mtu = EXTRACT_16BITS(&mp->nexthopmtu);
if (mtu) {
(void)snprintf(buf, sizeof(buf),
case ICMP_MASKREPLY:
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)snprintf(buf, sizeof(buf),
"time stamp query id %u seq %u",
- (unsigned)ntohs(dp->icmp_id),
- (unsigned)ntohs(dp->icmp_seq));
+ EXTRACT_16BITS(&dp->icmp_id),
+ EXTRACT_16BITS(&dp->icmp_seq));
break;
case ICMP_TSTAMPREPLY:
TCHECK(dp->icmp_ttime);
(void)snprintf(buf, sizeof(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;
+ "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 %d: %s", plen, str);
- if (vflag) {
+ (void)printf("ICMP %s, length %u", str, plen);
+ if (vflag && !fragmented) { /* don't attempt checksumming if this is a frag */
u_int16_t sum, icmp_sum;
+ struct cksum_vec vec[1];
if (TTEST2(*bp, plen)) {
- sum = in_cksum((u_short*)dp, plen, 0);
+ vec[0].ptr = (const u_int8_t *)(void *)dp;
+ vec[0].len = plen;
+ sum = in_cksum(vec, 1);
if (sum != 0) {
- icmp_sum = ntohs(dp->icmp_cksum);
+ icmp_sum = EXTRACT_16BITS(&dp->icmp_cksum);
(void)printf(" (wrong icmp cksum %x (->%x)!)",
icmp_sum,
in_cksum_shouldbe(icmp_sum, sum));
}
}
}
- if (vflag > 1 && !ICMP_INFOTYPE(dp->icmp_type)) {
+
+ /*
+ * print the remnants of the IP packet.
+ * save the snaplength as this may get overidden in the IP printer.
+ */
+ if (vflag >= 1 && !ICMP_INFOTYPE(dp->icmp_type)) {
bp += 8;
- (void)printf(" for ");
+ (void)printf("\n\t");
ip = (struct ip *)bp;
snaplen = snapend - bp;
- ip_print(bp, ntohs(ip->ip_len));
+ snapend_save = snapend;
+ ip_print(gndo, bp, EXTRACT_16BITS(&ip->ip_len));
+ snapend = snapend_save;
}
+
+ /*
+ * Attempt to decode the MPLS extensions only for some ICMP types.
+ */
+ if (vflag >= 1 && plen > ICMP_EXTD_MINLEN && ICMP_MPLS_EXT_TYPE(dp->icmp_type)) {
+
+ 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 u_int8_t *)(void *)&ext_dp->icmp_ext_version_res;
+ vec[0].len = plen - ICMP_EXTD_MINLEN;
+ if (in_cksum(vec, 1)) {
+ return;
+ }
+ }
+
+ printf("\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) {
+ printf(" packet not supported");
+ return;
+ }
+
+ hlen = plen - ICMP_EXTD_MINLEN;
+ vec[0].ptr = (const u_int8_t *)(void *)&ext_dp->icmp_ext_version_res;
+ vec[0].len = hlen;
+ printf(", 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 = (u_int8_t *)ext_dp->icmp_ext_data;
+
+ while (hlen > sizeof(struct icmp_mpls_ext_object_header_t)) {
+
+ icmp_mpls_ext_object_header = (struct icmp_mpls_ext_object_header_t *)obj_tptr;
+ 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);
+
+ printf("\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:
+ TCHECK2(*obj_tptr, 4);
+ raw_label = EXTRACT_32BITS(obj_tptr);
+ printf("\n\t label %u, exp %u", MPLS_LABEL(raw_label), MPLS_EXP(raw_label));
+ if (MPLS_STACK(raw_label))
+ printf(", [S]");
+ printf(", ttl %u", MPLS_TTL(raw_label));
+ break;
+ default:
+ print_unknown_data(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(obj_tptr, "\n\t ", obj_tlen);
+ break;
+ }
+ if (hlen < obj_tlen)
+ break;
+ hlen -= obj_tlen;
+ obj_tptr += obj_tlen;
+ }
+ }
+
return;
trunc:
fputs("[|icmp]", stdout);
projects / tcpdump / blobdiff