]> The Tcpdump Group git mirrors - tcpdump/blobdiff - print-icmp.c
CHANGES: Add/move change(s) backported to 4.99
[tcpdump] / print-icmp.c
index 2b8c1ff76e6311447d411169336523c300653c39..9b53a48a28b94abd7cd6d19034eb8a124d0cebe2 100644 (file)
@@ -21,9 +21,7 @@
 
 /* \summary: Internet Control Message Protocol (ICMP) printer */
 
-#ifdef HAVE_CONFIG_H
 #include <config.h>
-#endif
 
 #include "netdissect-stdinc.h"
 
@@ -86,13 +84,10 @@ struct icmp {
 #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.
+ * 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.
@@ -150,7 +145,7 @@ struct icmp {
        ((type) == ICMP_UNREACH || (type) == ICMP_SOURCEQUENCH || \
        (type) == ICMP_REDIRECT || (type) == ICMP_TIMXCEED || \
        (type) == ICMP_PARAMPROB)
-#define        ICMP_MPLS_EXT_TYPE(type) \
+#define        ICMP_MULTIPART_EXT_TYPE(type) \
        ((type) == ICMP_UNREACH || \
          (type) == ICMP_TIMXCEED || \
          (type) == ICMP_PARAMPROB)
@@ -202,42 +197,6 @@ static const struct tok icmp2str[] = {
        { 0,                            NULL }
 };
 
-/* Formats for most of the ICMP_UNREACH codes */
-static const struct tok unreach2str[] = {
-       { ICMP_UNREACH_NET,             "net %s unreachable" },
-       { ICMP_UNREACH_HOST,            "host %s unreachable" },
-       { ICMP_UNREACH_SRCFAIL,
-           "%s unreachable - source route failed" },
-       { ICMP_UNREACH_NET_UNKNOWN,     "net %s unreachable - unknown" },
-       { ICMP_UNREACH_HOST_UNKNOWN,    "host %s unreachable - unknown" },
-       { ICMP_UNREACH_ISOLATED,
-           "%s unreachable - source host isolated" },
-       { ICMP_UNREACH_NET_PROHIB,
-           "net %s unreachable - admin prohibited" },
-       { ICMP_UNREACH_HOST_PROHIB,
-           "host %s unreachable - admin prohibited" },
-       { ICMP_UNREACH_TOSNET,
-           "net %s unreachable - tos prohibited" },
-       { ICMP_UNREACH_TOSHOST,
-           "host %s unreachable - tos prohibited" },
-       { ICMP_UNREACH_FILTER_PROHIB,
-           "host %s unreachable - admin prohibited filter" },
-       { ICMP_UNREACH_HOST_PRECEDENCE,
-           "host %s unreachable - host precedence violation" },
-       { ICMP_UNREACH_PRECEDENCE_CUTOFF,
-           "host %s unreachable - precedence cutoff" },
-       { 0,                            NULL }
-};
-
-/* Formats for the ICMP_REDIRECT codes */
-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 host %s" },
-       { 0,                            NULL }
-};
-
 /* rfc1191 */
 struct mtu_discovery {
        nd_uint16_t unused;
@@ -257,13 +216,17 @@ struct id_rdiscovery {
 };
 
 /*
- * draft-bonica-internet-icmp-08
+ * 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 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 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.
@@ -295,15 +258,34 @@ struct icmp_ext_t {
     nd_byte     icmp_ext_data[1];
 };
 
-struct icmp_mpls_ext_object_header_t {
+/*
+ * 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_mpls_ext_obj_values[] = {
+static const struct tok icmp_multipart_ext_obj_values[] = {
     { 1, "MPLS Stack Entry" },
-    { 2, "Extended Payload" },
+    { 2, "Interface Identification" },
     { 0, NULL}
 };
 
@@ -322,7 +304,7 @@ icmp_tstamp_print(u_int tstamp)
     sec = tstamp / 1000;
     min = sec / 60; sec -= min * 60;
     hrs = min / 60; min -= hrs * 60;
-    nd_snprintf(buf, sizeof(buf), "%02u:%02u:%02u.%03u",hrs,min,sec,msec);
+    snprintf(buf, sizeof(buf), "%02u:%02u:%02u.%03u",hrs,min,sec,msec);
     return buf;
 }
 
@@ -335,15 +317,15 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
        uint8_t icmp_type, icmp_code;
         const struct icmp_ext_t *ext_dp;
        const struct ip *ip;
-       const char *str, *fmt;
+       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 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;
+       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];
 
@@ -353,15 +335,13 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
        ip = (const struct ip *)bp2;
        str = buf;
 
-       ND_TCHECK_1(dp->icmp_code);
        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:
-               ND_TCHECK_2(dp->icmp_seq);
-               (void)nd_snprintf(buf, sizeof(buf), "echo %s, id %u, seq %u",
+               (void)snprintf(buf, sizeof(buf), "echo %s, id %u, seq %u",
                                icmp_type == ICMP_ECHO ?
                                "request" : "reply",
                                GET_BE_U_2(dp->icmp_id),
@@ -369,14 +349,24 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
                break;
 
        case ICMP_UNREACH:
-               ND_TCHECK_4(dp->icmp_ip.ip_dst);
                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:
-                       ND_TCHECK_1(dp->icmp_ip.ip_p);
-                       (void)nd_snprintf(buf, sizeof(buf),
+                       (void)snprintf(buf, sizeof(buf),
                            "%s protocol %u unreachable",
-                           ipaddr_string(ndo, dp->icmp_ip.ip_dst),
+                           GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
                            GET_U_1(dp->icmp_ip.ip_p));
                        break;
 
@@ -385,29 +375,28 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
                        oip = &dp->icmp_ip;
                        hlen = IP_HL(oip) * 4;
                        ouh = (const struct udphdr *)(((const u_char *)oip) + hlen);
-                       ND_TCHECK_2(ouh->uh_dport);
                        dport = GET_BE_U_2(ouh->uh_dport);
                        ip_proto = GET_U_1(oip->ip_p);
                        switch (ip_proto) {
 
                        case IPPROTO_TCP:
-                               (void)nd_snprintf(buf, sizeof(buf),
+                               (void)snprintf(buf, sizeof(buf),
                                        "%s tcp port %s unreachable",
-                                       ipaddr_string(ndo, oip->ip_dst),
+                                       GET_IPADDR_STRING(oip->ip_dst),
                                        tcpport_string(ndo, dport));
                                break;
 
                        case IPPROTO_UDP:
-                               (void)nd_snprintf(buf, sizeof(buf),
+                               (void)snprintf(buf, sizeof(buf),
                                        "%s udp port %s unreachable",
-                                       ipaddr_string(ndo, oip->ip_dst),
+                                       GET_IPADDR_STRING(oip->ip_dst),
                                        udpport_string(ndo, dport));
                                break;
 
                        default:
-                               (void)nd_snprintf(buf, sizeof(buf),
+                               (void)snprintf(buf, sizeof(buf),
                                        "%s protocol %u port %u unreachable",
-                                       ipaddr_string(ndo, oip->ip_dst),
+                                       GET_IPADDR_STRING(oip->ip_dst),
                                        ip_proto, dport);
                                break;
                        }
@@ -419,33 +408,130 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
                        mp = (const struct mtu_discovery *)(const u_char *)&dp->icmp_void;
                        mtu = GET_BE_U_2(mp->nexthopmtu);
                        if (mtu) {
-                               (void)nd_snprintf(buf, sizeof(buf),
+                               (void)snprintf(buf, sizeof(buf),
                                    "%s unreachable - need to frag (mtu %u)",
-                                   ipaddr_string(ndo, dp->icmp_ip.ip_dst), mtu);
+                                   GET_IPADDR_STRING(dp->icmp_ip.ip_dst), mtu);
                        } else {
-                               (void)nd_snprintf(buf, sizeof(buf),
+                               (void)snprintf(buf, sizeof(buf),
                                    "%s unreachable - need to frag",
-                                   ipaddr_string(ndo, dp->icmp_ip.ip_dst));
+                                   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:
-                       fmt = tok2str(unreach2str, "#%u %%s unreachable",
+                       (void)snprintf(buf, sizeof(buf),
+                           "%s unreachable - #%u",
+                           GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
                            icmp_code);
-                       (void)nd_snprintf(buf, sizeof(buf), fmt,
-                           ipaddr_string(ndo, dp->icmp_ip.ip_dst));
                        break;
                }
                break;
 
        case ICMP_REDIRECT:
-               ND_TCHECK_4(dp->icmp_ip.ip_dst);
-               fmt = tok2str(type2str, "redirect-#%u %%s to net %%s",
-                   icmp_code);
-               (void)nd_snprintf(buf, sizeof(buf), fmt,
-                   ipaddr_string(ndo, dp->icmp_ip.ip_dst),
-                   ipaddr_string(ndo, dp->icmp_gwaddr));
+               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:
@@ -454,7 +540,7 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
                const struct id_rdiscovery *idp;
                u_int lifetime, num, size;
 
-               (void)nd_snprintf(buf, sizeof(buf), "router advertisement");
+               (void)snprintf(buf, sizeof(buf), "router advertisement");
                cp = buf + strlen(buf);
 
                ihp = (const struct ih_rdiscovery *)&dp->icmp_void;
@@ -463,13 +549,13 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
                cp = buf + strlen(buf);
                lifetime = GET_BE_U_2(ihp->ird_lifetime);
                if (lifetime < 60) {
-                       (void)nd_snprintf(cp, sizeof(buf) - (cp - buf), "%u",
+                       (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u",
                            lifetime);
                } else if (lifetime < 60 * 60) {
-                       (void)nd_snprintf(cp, sizeof(buf) - (cp - buf), "%u:%02u",
+                       (void)snprintf(cp, sizeof(buf) - (cp - buf), "%u:%02u",
                            lifetime / 60, lifetime % 60);
                } else {
-                       (void)nd_snprintf(cp, sizeof(buf) - (cp - buf),
+                       (void)snprintf(cp, sizeof(buf) - (cp - buf),
                            "%u:%02u:%02u",
                            lifetime / 3600,
                            (lifetime % 3600) / 60,
@@ -478,20 +564,20 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
                cp = buf + strlen(buf);
 
                num = GET_U_1(ihp->ird_addrnum);
-               (void)nd_snprintf(cp, sizeof(buf) - (cp - buf), " %u:", num);
+               (void)snprintf(cp, sizeof(buf) - (cp - buf), " %u:", num);
                cp = buf + strlen(buf);
 
                size = GET_U_1(ihp->ird_addrsiz);
                if (size != 2) {
-                       (void)nd_snprintf(cp, sizeof(buf) - (cp - buf),
+                       (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)nd_snprintf(cp, sizeof(buf) - (cp - buf), " {%s %u}",
-                           ipaddr_string(ndo, idp->ird_addr),
+                       (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;
@@ -513,7 +599,7 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
                        break;
 
                default:
-                       (void)nd_snprintf(buf, sizeof(buf), "time exceeded-#%u",
+                       (void)snprintf(buf, sizeof(buf), "time exceeded-#%u",
                            icmp_code);
                        break;
                }
@@ -521,25 +607,22 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
 
        case ICMP_PARAMPROB:
                if (icmp_code)
-                       (void)nd_snprintf(buf, sizeof(buf),
+                       (void)snprintf(buf, sizeof(buf),
                            "parameter problem - code %u", icmp_code);
                else {
-                       ND_TCHECK_1(dp->icmp_pptr);
-                       (void)nd_snprintf(buf, sizeof(buf),
+                       (void)snprintf(buf, sizeof(buf),
                            "parameter problem - octet %u",
                            GET_U_1(dp->icmp_pptr));
                }
                break;
 
        case ICMP_MASKREPLY:
-               ND_TCHECK_4(dp->icmp_mask);
-               (void)nd_snprintf(buf, sizeof(buf), "address mask is 0x%08x",
+               (void)snprintf(buf, sizeof(buf), "address mask is 0x%08x",
                    GET_BE_U_4(dp->icmp_mask));
                break;
 
        case ICMP_TSTAMP:
-               ND_TCHECK_2(dp->icmp_seq);
-               (void)nd_snprintf(buf, sizeof(buf),
+               (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));
@@ -547,15 +630,15 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
 
        case ICMP_TSTAMPREPLY:
                ND_TCHECK_4(dp->icmp_ttime);
-               (void)nd_snprintf(buf, sizeof(buf),
+               (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)nd_snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", recv %s",
+                (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", recv %s",
                          icmp_tstamp_print(GET_BE_U_4(dp->icmp_rtime)));
-                (void)nd_snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", xmit %s",
+                (void)snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", xmit %s",
                          icmp_tstamp_print(GET_BE_U_4(dp->icmp_ttime)));
                 break;
 
@@ -582,30 +665,42 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
 
         /*
          * print the remnants of the IP packet.
-         * save the snaplength as this may get overidden in the IP printer.
+         * 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;
-               ND_TCHECK_2(ip->ip_len);
+               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->ndo_snapend = snapend_save;
        }
 
        /* ndo_protocol reassignment after ip_print() call */
        ndo->ndo_protocol = "icmp";
 
         /*
-         * Attempt to decode the MPLS extensions only for some ICMP types.
+         * Attempt to decode multi-part message extensions (rfc4884) only for some ICMP types.
          */
-        if (ndo->ndo_vflag >= 1 && plen > ICMP_EXTD_MINLEN && ICMP_MPLS_EXT_TYPE(icmp_type)) {
+        if (ndo->ndo_vflag >= 1 && plen > ICMP_EXTD_MINLEN && ICMP_MULTIPART_EXT_TYPE(icmp_type)) {
 
             ND_TCHECK_SIZE(ext_dp);
 
             /*
-             * Check first if the mpls extension header shows a non-zero length.
+             * 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.
@@ -619,14 +714,14 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
                 }
             }
 
-            ND_PRINT("\n\tMPLS extension v%u",
-                   ICMP_MPLS_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)));
+            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_MPLS_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)) !=
-                ICMP_MPLS_EXT_VERSION) {
+            if (ICMP_EXT_EXTRACT_VERSION(*(ext_dp->icmp_ext_version_res)) !=
+                ICMP_EXT_VERSION) {
                 ND_PRINT(" packet not supported");
                 return;
             }
@@ -644,37 +739,36 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
             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)) {
+            while (hlen > sizeof(struct icmp_multipart_ext_object_header_t)) {
 
-                icmp_mpls_ext_object_header = (const struct icmp_mpls_ext_object_header_t *)obj_tptr;
-                ND_TCHECK_SIZE(icmp_mpls_ext_object_header);
-                obj_tlen = GET_BE_U_2(icmp_mpls_ext_object_header->length);
-                obj_class_num = GET_U_1(icmp_mpls_ext_object_header->class_num);
-                obj_ctype = GET_U_1(icmp_mpls_ext_object_header->ctype);
-                obj_tptr += sizeof(struct icmp_mpls_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_mpls_ext_obj_values,"unknown",obj_class_num),
+                       tok2str(icmp_multipart_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 */
+                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_mpls_ext_object_header_t))) {
+                    (obj_tlen < sizeof(struct icmp_multipart_ext_object_header_t))) {
                     return;
                 }
-                obj_tlen-=sizeof(struct icmp_mpls_ext_object_header_t);
+                obj_tlen-=sizeof(struct icmp_multipart_ext_object_header_t);
 
                 switch (obj_class_num) {
-                case 1:
+                case MPLS_STACK_ENTRY_OBJECT_CLASS:
                     switch(obj_ctype) {
                     case 1:
-                        ND_TCHECK_4(obj_tptr);
                         raw_label = GET_BE_U_4(obj_tptr);
-                        ND_PRINT("\n\t    label %u, exp %u", MPLS_LABEL(raw_label), MPLS_EXP(raw_label));
+                        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));
@@ -684,11 +778,6 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
                     }
                     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;