]> The Tcpdump Group git mirrors - tcpdump/blobdiff - print-icmp.c
remove redundant ND_TCHECK, let GET_ routines handle checks
[tcpdump] / print-icmp.c
index 86da44bd99ec2bde3c99c9fec3812db6585ce258..dd767ebab094d9d7112a70609efb4e38fe17773b 100644 (file)
@@ -202,42 +202,6 @@ 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;
@@ -322,7 +286,7 @@ 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;
 }
 
@@ -335,7 +299,7 @@ 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;
@@ -343,7 +307,8 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
         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;
+       u_int hlen, mtu, obj_tlen, obj_class_num, obj_ctype;
+       uint16_t dport;
        char buf[MAXHOSTNAMELEN + 100];
        struct cksum_vec vec[1];
 
@@ -353,31 +318,39 @@ 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 = EXTRACT_U_1(dp->icmp_type);
-       icmp_code = EXTRACT_U_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",
-                               EXTRACT_BE_U_2(dp->icmp_id),
-                               EXTRACT_BE_U_2(dp->icmp_seq));
+                               GET_BE_U_2(dp->icmp_id),
+                               GET_BE_U_2(dp->icmp_seq));
                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),
-                           EXTRACT_U_1(dp->icmp_ip.ip_p));
+                           GET_IPADDR_STRING(dp->icmp_ip.ip_dst),
+                           GET_U_1(dp->icmp_ip.ip_p));
                        break;
 
                case ICMP_UNREACH_PORT:
@@ -385,29 +358,28 @@ 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 = EXTRACT_BE_U_2(ouh->uh_dport);
-                       ip_proto = EXTRACT_U_1(oip->ip_p);
+                       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;
                        }
@@ -417,35 +389,132 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
                    {
                        const struct mtu_discovery *mp;
                        mp = (const struct mtu_discovery *)(const u_char *)&dp->icmp_void;
-                       mtu = EXTRACT_BE_U_2(mp->nexthopmtu);
+                       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:
@@ -454,22 +523,22 @@ 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;
                ND_TCHECK_SIZE(ihp);
                (void)strncpy(cp, " lifetime ", sizeof(buf) - (cp - buf));
                cp = buf + strlen(buf);
-               lifetime = EXTRACT_BE_U_2(ihp->ird_lifetime);
+               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,
@@ -477,24 +546,25 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
                }
                cp = buf + strlen(buf);
 
-               num = EXTRACT_U_1(ihp->ird_addrnum);
-               (void)nd_snprintf(cp, sizeof(buf) - (cp - buf), " %u:", num);
+               num = GET_U_1(ihp->ird_addrnum);
+               (void)snprintf(cp, sizeof(buf) - (cp - buf), " %u:", num);
                cp = buf + strlen(buf);
 
-               size = EXTRACT_U_1(ihp->ird_addrsiz);
+               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) {
+               while (num > 0) {
                        ND_TCHECK_SIZE(idp);
-                       (void)nd_snprintf(cp, sizeof(buf) - (cp - buf), " {%s %u}",
-                           ipaddr_string(ndo, idp->ird_addr),
-                           EXTRACT_BE_U_4(idp->ird_pref));
+                       (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;
@@ -512,7 +582,7 @@ 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;
                }
@@ -520,41 +590,39 @@ 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),
-                           "parameter problem - octet %u", EXTRACT_U_1(dp->icmp_pptr));
+                       (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",
-                   EXTRACT_BE_U_4(dp->icmp_mask));
+               (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",
-                   EXTRACT_BE_U_2(dp->icmp_id),
-                   EXTRACT_BE_U_2(dp->icmp_seq));
+                   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)nd_snprintf(buf, sizeof(buf),
+               (void)snprintf(buf, sizeof(buf),
                    "time stamp reply id %u seq %u: org %s",
-                               EXTRACT_BE_U_2(dp->icmp_id),
-                               EXTRACT_BE_U_2(dp->icmp_seq),
-                               icmp_tstamp_print(EXTRACT_BE_U_4(dp->icmp_otime)));
-
-                (void)nd_snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", recv %s",
-                         icmp_tstamp_print(EXTRACT_BE_U_4(dp->icmp_rtime)));
-                (void)nd_snprintf(buf+strlen(buf),sizeof(buf)-strlen(buf),", xmit %s",
-                         icmp_tstamp_print(EXTRACT_BE_U_4(dp->icmp_ttime)));
+                               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:
@@ -570,7 +638,7 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
                        vec[0].len = plen;
                        sum = in_cksum(vec, 1);
                        if (sum != 0) {
-                               uint16_t icmp_sum = EXTRACT_BE_U_2(dp->icmp_cksum);
+                               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));
@@ -587,8 +655,7 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
                ND_PRINT("\n\t");
                ip = (const struct ip *)bp;
                 snapend_save = ndo->ndo_snapend;
-               ND_TCHECK_2(ip->ip_len);
-               ip_print(ndo, bp, EXTRACT_BE_U_2(ip->ip_len));
+               ip_print(ndo, bp, GET_BE_U_2(ip->ip_len));
                 ndo->ndo_snapend = snapend_save;
        }
 
@@ -608,7 +675,7 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
              * to check if an extension header is present. This is expedient,
              * however not all implementations set the length field proper.
              */
-            if (EXTRACT_U_1(ext_dp->icmp_length) == 0 &&
+            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;
@@ -634,7 +701,7 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
                 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",
-                       EXTRACT_BE_U_2(ext_dp->icmp_ext_checksum),
+                       GET_BE_U_2(ext_dp->icmp_ext_checksum),
                        in_cksum(vec, 1) ? "in" : "",
                        hlen);
             }
@@ -646,9 +713,9 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
 
                 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 = EXTRACT_BE_U_2(icmp_mpls_ext_object_header->length);
-                obj_class_num = EXTRACT_U_1(icmp_mpls_ext_object_header->class_num);
-                obj_ctype = EXTRACT_U_1(icmp_mpls_ext_object_header->ctype);
+                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);
 
                 ND_PRINT("\n\t  %s Object (%u), Class-Type: %u, length %u",
@@ -670,8 +737,7 @@ icmp_print(netdissect_options *ndo, const u_char *bp, u_int plen, const u_char *
                 case 1:
                     switch(obj_ctype) {
                     case 1:
-                        ND_TCHECK_4(obj_tptr);
-                        raw_label = EXTRACT_BE_U_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));
                         if (MPLS_STACK(raw_label))
                             ND_PRINT(", [S]");