]> The Tcpdump Group git mirrors - tcpdump/blobdiff - print-isoclns.c
Add SunATM support, based on code from Yen Yen Lim at North Dakota State
[tcpdump] / print-isoclns.c
index bdb39752cdaf1b6e20411e5a3138bcc550fef5c3..d9b5e9d255f39fe8f240823c81d3556f0c8e873c 100644 (file)
  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
  * Original code by Matt Thomas, Digital Equipment Corporation
+ *
+ * Extensively modified by Hannes Gredler ([email protected]) for more
+ * complete IS-IS support.
  */
 
 #ifndef lint
 static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-isoclns.c,v 1.15 1999-10-07 23:47:11 mcr Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-isoclns.c,v 1.52 2002-06-29 04:33:31 guy Exp $ (LBL)";
+#endif
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
 #endif
 
 #include <sys/types.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 <stdio.h>
+#include <string.h>
 
 #include "interface.h"
 #include "addrtoname.h"
 #include "ethertype.h"
+#include "ether.h"
+#include "extract.h"
+
+#define        NLPID_CLNS      129     /* 0x81 */
+#define        NLPID_ESIS      130     /* 0x82 */
+#define        NLPID_ISIS      131     /* 0x83 */
+#define NLPID_IP6       0x8e
+#define NLPID_IP        0xcc
+#define        NLPID_NULLNS    0
+
+/*
+ * IS-IS is defined in ISO 10589.  Look there for protocol definitions.
+ */
+
+#define SYSTEM_ID_LEN  ETHER_ADDR_LEN
+#define NODE_ID_LEN     SYSTEM_ID_LEN+1
+#define LSP_ID_LEN      SYSTEM_ID_LEN+2
+
+#define ISIS_VERSION   1
+#define PDU_TYPE_MASK  0x1F
+#define PRIORITY_MASK  0x7F
+
+#define L1_LAN_IIH     15
+#define L2_LAN_IIH     16
+#define PTP_IIH                17
+#define L1_LSP         18
+#define L2_LSP         20
+#define L1_CSNP        24
+#define L2_CSNP        25
+#define L1_PSNP                26
+#define L2_PSNP                27
+
+static struct tok isis_pdu_values[] = {
+    { L1_LAN_IIH,       "L1 Lan IIH"},
+    { L2_LAN_IIH,       "L2 Lan IIH"},
+    { PTP_IIH,          "p2p IIH"},
+    { L1_LSP,           "L1 LSP"},
+    { L2_LSP,           "L2 LSP"},
+    { L1_CSNP,          "L1 CSNP"},
+    { L2_CSNP,          "L2 CSNP"},
+    { L1_PSNP,          "L1 PSNP"},
+    { L2_PSNP,          "L2 PSNP"},
+    { 0, NULL}
+};
+
+/*
+ * A TLV is a tuple of a type, length and a value and is normally used for
+ * encoding information in all sorts of places.  This is an enumeration of
+ * the well known types.
+ *
+ * list taken from draft-ietf-isis-wg-tlv-codepoints-01.txt
+ */
+
+#define TLV_AREA_ADDR           1
+#define TLV_IS_REACH            2
+#define TLV_ESNEIGH             3
+#define TLV_PART_DIS            4
+#define TLV_PREFIX_NEIGH        5
+#define TLV_ISNEIGH             6
+#define TLV_ISNEIGH_VARLEN      7
+#define TLV_PADDING             8
+#define TLV_LSP                 9
+#define TLV_AUTH                10
+#define TLV_CHECKSUM            12
+#define TLV_LSP_BUFFERSIZE      14
+#define TLV_EXT_IS_REACH        22
+#define TLV_IS_ALIAS_ID         24
+#define TLV_DECNET_PHASE4       42
+#define TLV_LUCENT_PRIVATE      66
+#define TLV_IP_REACH            128
+#define TLV_PROTOCOLS           129
+#define TLV_IP_REACH_EXT        130
+#define TLV_IDRP_INFO           131
+#define TLV_IPADDR              132
+#define TLV_IPAUTH              133
+#define TLV_TE_ROUTER_ID        134
+#define TLV_EXT_IP_REACH        135
+#define TLV_HOSTNAME            137
+#define TLV_SHARED_RISK_GROUP   138
+#define TLV_NORTEL_PRIVATE1     176
+#define TLV_NORTEL_PRIVATE2     177
+#define TLV_RESTART_SIGNALING   211
+#define TLV_MT_IS_REACH         222
+#define TLV_MT_SUPPORTED        229
+#define TLV_IP6ADDR             232
+#define TLV_MT_IP_REACH         235
+#define TLV_IP6_REACH           236
+#define TLV_MT_IP6_REACH        237
+#define TLV_PTP_ADJ             240
+
+static struct tok isis_tlv_values[] = {
+    { TLV_AREA_ADDR,        "Area address(es)"},
+    { TLV_IS_REACH,          "IS Reachability"},
+    { TLV_ESNEIGH,           "ES Neighbor(s)"},
+    { TLV_PART_DIS,          "Partition DIS"},
+    { TLV_PREFIX_NEIGH,      "Prefix Neighbors"},
+    { TLV_ISNEIGH,           "IS Neighbor(s)"},
+    { TLV_ISNEIGH_VARLEN,    "IS Neighbor(s) (variable length)"},
+    { TLV_PADDING,           "Padding"},
+    { TLV_LSP,               "LSP entries"},
+    { TLV_AUTH,              "Authentication"},
+    { TLV_CHECKSUM,          "Checksum"},
+    { TLV_LSP_BUFFERSIZE,    "LSP Buffersize"},
+    { TLV_EXT_IS_REACH,      "Extended IS Reachability"},
+    { TLV_IS_ALIAS_ID,       "IS Alias ID"},
+    { TLV_DECNET_PHASE4,     "DECnet Phase IV"},
+    { TLV_LUCENT_PRIVATE,    "Lucent Proprietary"},
+    { TLV_IP_REACH,          "IPv4 Internal reachability"},
+    { TLV_PROTOCOLS,         "Protocols supported"},
+    { TLV_IP_REACH_EXT,      "IPv4 External reachability"},
+    { TLV_IDRP_INFO,         "Inter-Domain Information Type"},
+    { TLV_IPADDR,            "IPv4 Interface address(es)"},
+    { TLV_IPAUTH,            "IPv4 authentication (deprecated)"},
+    { TLV_TE_ROUTER_ID,      "Traffic Engineering Router ID"},
+    { TLV_EXT_IP_REACH,      "Extended IPv4 reachability"},
+    { TLV_HOSTNAME,          "Hostname"},
+    { TLV_SHARED_RISK_GROUP, "Shared Risk Link Group"},
+    { TLV_NORTEL_PRIVATE1,   "Nortel Proprietary"},
+    { TLV_NORTEL_PRIVATE2,   "Nortel Proprietary"},
+    { TLV_RESTART_SIGNALING, "Restart Signaling"},
+    { TLV_MT_IS_REACH,       "Multi Topology IS Reachability"},
+    { TLV_MT_SUPPORTED,      "Multi Topology"},
+    { TLV_IP6ADDR,           "IPv6 Interface address(es)"},
+    { TLV_MT_IP_REACH,       "Multi-Topology IPv4 reachability"},
+    { TLV_IP6_REACH,         "IPv6 reachability"},
+    { TLV_MT_IP6_REACH,      "Multi-Topology IP6 reachability"},
+    { TLV_PTP_ADJ,           "Point-to-point Adjacency State"},
+    { 0, NULL }
+};
 
-#define        CLNS    129
-#define        ESIS    130
-#define        ISIS    131
-#define        NULLNS  0
+#define SUBTLV_EXT_IS_REACH_ADMIN_GROUP           3
+#define SUBTLV_EXT_IS_REACH_LINK_LOCAL_ID         4
+#define SUBTLV_EXT_IS_REACH_LINK_REMOTE_ID        5
+#define SUBTLV_EXT_IS_REACH_IPV4_INTF_ADDR        6
+#define SUBTLV_EXT_IS_REACH_IPV4_NEIGHBOR_ADDR    8
+#define SUBTLV_EXT_IS_REACH_MAX_LINK_BW           9
+#define SUBTLV_EXT_IS_REACH_RESERVABLE_BW        10
+#define SUBTLV_EXT_IS_REACH_UNRESERVED_BW        11
+#define SUBTLV_EXT_IS_REACH_TE_METRIC            18
+#define SUBTLV_EXT_IS_REACH_LINK_PROTECTION_TYPE 20
+#define SUBTLV_EXT_IS_REACH_INTF_SW_CAP_DESCR    21
 
-static int osi_cksum(const u_char *, u_int, const u_char *, u_char *, u_char *);
+#define SUBTLV_IP_REACH_ADMIN_TAG32               1
+#define SUBTLV_IP_REACH_ADMIN_TAG64               2
+
+#define SUBTLV_AUTH_SIMPLE        1
+#define SUBTLV_AUTH_MD5          54
+#define SUBTLV_AUTH_MD5_LEN      16
+#define SUBTLV_AUTH_PRIVATE     255
+
+static struct tok isis_subtlv_auth_values[] = {
+    { SUBTLV_AUTH_SIMPLE,      "simple text password"},
+    { SUBTLV_AUTH_MD5,         "HMAC-MD5 password"},
+    { SUBTLV_AUTH_PRIVATE,     "Routing Domain private password"},
+    { 0, NULL }
+};
+
+#define SUBTLV_IDRP_RES           0
+#define SUBTLV_IDRP_LOCAL         1
+#define SUBTLV_IDRP_ASN           2
+
+static struct tok isis_subtlv_idrp_values[] = {
+    { SUBTLV_IDRP_RES,         "Reserved"},
+    { SUBTLV_IDRP_LOCAL,       "Routing-Domain Specific"},
+    { SUBTLV_IDRP_ASN,         "AS Number Tag"},
+    { 0, NULL}
+};
+
+#define ISIS_8BIT_MASK(x)                  ((x)&0xff)
+
+#define ISIS_MASK_LSP_OL_BIT(x)            ((x)&0x4)
+#define ISIS_MASK_LSP_ISTYPE_BITS(x)       ((x)&0x3)
+#define ISIS_MASK_LSP_PARTITION_BIT(x)     ((x)&0x80)
+#define ISIS_MASK_LSP_ATT_BITS(x)          ((x)&0x78)
+#define ISIS_MASK_LSP_ATT_ERROR_BIT(x)     ((x)&0x40)
+#define ISIS_MASK_LSP_ATT_EXPENSE_BIT(x)   ((x)&0x20)
+#define ISIS_MASK_LSP_ATT_DELAY_BIT(x)     ((x)&0x10)
+#define ISIS_MASK_LSP_ATT_DEFAULT_BIT(x)   ((x)&0x8)
+
+#define ISIS_MASK_MTID(x)                  ((x)&0xfff)
+#define ISIS_MASK_MTSUB(x)                 ((x)&0x8000)
+#define ISIS_MASK_MTATT(x)                 ((x)&0x4000)
+
+#define ISIS_MASK_TLV_EXT_IP_UPDOWN(x)     ((x)&0x80)
+#define ISIS_MASK_TLV_EXT_IP_SUBTLV(x)     ((x)&0x40)
+
+#define ISIS_MASK_TLV_IP6_UPDOWN(x)        ((x)&0x80)
+#define ISIS_MASK_TLV_IP6_IE(x)            ((x)&0x40)
+#define ISIS_MASK_TLV_IP6_SUBTLV(x)        ((x)&0x20)
+
+#define ISIS_MASK_TLV_RESTART_RR(x)        ((x)&0x1)
+#define ISIS_MASK_TLV_RESTART_RA(x)        ((x)&0x2)
+
+#define ISIS_LSP_TLV_METRIC_SUPPORTED(x)   ((x)&0x80)
+#define ISIS_LSP_TLV_METRIC_IE(x)          ((x)&0x40)
+#define ISIS_LSP_TLV_METRIC_UPDOWN(x)      ((x)&0x80)
+#define ISIS_LSP_TLV_METRIC_VALUE(x)      ((x)&0x3f)
+
+#define ISIS_MASK_TLV_SHARED_RISK_GROUP(x) ((x)&0x1)
+
+static const char *isis_gmpls_link_prot_values[] = {
+    "Extra",
+    "Unprotected",
+    "Shared",
+    "Dedicated 1:1",
+    "Dedicated 1+1",
+    "Enhanced",
+    "Reserved",
+    "Reserved"
+};
+
+static struct tok isis_gmpls_sw_cap_values[] = {
+    { 1,       "Packet-Switch Capable-1"},
+    { 2,       "Packet-Switch Capable-2"},
+    { 3,       "Packet-Switch Capable-3"},
+    { 4,       "Packet-Switch Capable-4"},
+    { 51,      "Layer-2 Switch Capable"},
+    { 100,     "Time-Division-Multiplex"},
+    { 150,     "Lambda-Switch Capable"},
+    { 200,     "Fiber-Switch Capable"},
+    { 0, NULL }
+};
+
+static struct tok isis_gmpls_lsp_enc_values[] = {
+    { 1,    "Packet"},
+    { 2,    "Ethernet V2/DIX"},
+    { 3,    "ANSI PDH"},
+    { 4,    "ETSI PDH"},
+    { 5,    "SDH ITU-T G.707"},
+    { 6,    "SONET ANSI T1.105"},
+    { 7,    "Digital Wrapper"},
+    { 8,    "Lambda (photonic)"},
+    { 9,    "Fiber"},
+    { 10,   "Ethernet 802.3"},
+    { 11,   "FiberChannel"},
+    { 0, NULL }
+};
+
+static struct tok isis_mt_values[] = {
+    { 0,    "IPv4 unicast"},
+    { 1,    "In-Band Management"},
+    { 2,    "IPv6 unicast"},
+    { 3,    "Multicast"},
+    { 4095, "Development, Experimental or Proprietary"},
+    { 0, NULL }
+};
+
+static struct tok isis_iih_circuit_type_values[] = {
+    { 1,    "Level 1 only"},
+    { 2,    "Level 2 only"},
+    { 3,    "Level 1, Level 2"},
+    { 0, NULL}
+};
+
+#define ISIS_LSP_TYPE_UNUSED0   0
+#define ISIS_LSP_TYPE_LEVEL_1   1
+#define ISIS_LSP_TYPE_UNUSED2   2
+#define ISIS_LSP_TYPE_LEVEL_2   3
+
+static struct tok isis_lsp_istype_values[] = {
+    { ISIS_LSP_TYPE_UNUSED0,   "Unused 0x0 (invalid)"},
+    { ISIS_LSP_TYPE_LEVEL_1,   "L1 IS"},
+    { ISIS_LSP_TYPE_UNUSED2,   "Unused 0x2 (invalid)"},
+    { ISIS_LSP_TYPE_LEVEL_2,   "L1L2 IS"},
+    { 0, NULL }
+};
+
+static struct tok isis_nlpid_values[] = {
+    { NLPID_CLNS,   "CLNS"},
+    { NLPID_IP,     "IPv4"},
+    { NLPID_IP6,    "IPv6"},
+    { 0, NULL }
+};
+
+/*
+ * Katz's point to point adjacency TLV uses codes to tell us the state of
+ * the remote adjacency.  Enumerate them.
+ */
+
+#define ISIS_PTP_ADJ_UP   0
+#define ISIS_PTP_ADJ_INIT 1
+#define ISIS_PTP_ADJ_DOWN 2
+
+
+static struct tok isis_ptp_adjancey_values[] = {
+    { ISIS_PTP_ADJ_UP,    "Up" },
+    { ISIS_PTP_ADJ_INIT,  "Initializing" },
+    { ISIS_PTP_ADJ_DOWN,  "Down" },
+    { 0, NULL}
+};
+
+struct isis_tlv_ptp_adj {
+    u_char adjacency_state;
+    u_char extd_local_circuit_id[4];
+    u_char neighbor_sysid[SYSTEM_ID_LEN];
+    u_char neighbor_extd_local_circuit_id[4];
+};
+
+static int osi_cksum(const u_char *, u_int);
 static void esis_print(const u_char *, u_int);
+static int isis_print(const u_char *, u_int);
+
+struct isis_metric_block {
+    u_char metric_default;
+    u_char metric_delay;
+    u_char metric_expense;
+    u_char metric_error;
+};
+
+struct isis_tlv_is_reach {
+    struct isis_metric_block isis_metric_block;
+    u_char neighbor_nodeid[NODE_ID_LEN];
+};
+
+struct isis_tlv_es_reach {
+    struct isis_metric_block isis_metric_block;
+    u_char neighbor_sysid[SYSTEM_ID_LEN];
+};
+
+struct isis_tlv_ip_reach {
+    struct isis_metric_block isis_metric_block;
+    u_char prefix[4];
+    u_char mask[4];
+};
+
+static struct tok isis_is_reach_virtual_values[] = {
+    { 0,    "IsNotVirtual"},
+    { 1,    "IsVirtual"},
+    { 0, NULL }
+};
+
+struct isis_common_header {
+    u_char nlpid;
+    u_char fixed_len;
+    u_char version;                    /* Protocol version? */
+    u_char id_length;
+    u_char pdu_type;                   /* 3 MSbs are reserved */
+    u_char pkt_version;                        /* Packet format version? */
+    u_char reserved;
+    u_char max_area;
+};
+
+struct isis_iih_lan_header {
+    u_char circuit_type;
+    u_char source_id[SYSTEM_ID_LEN];
+    u_char holding_time[2];
+    u_char pdu_len[2];
+    u_char priority;
+    u_char lan_id[NODE_ID_LEN];
+};
+
+struct isis_iih_ptp_header {
+    u_char circuit_type;
+    u_char source_id[SYSTEM_ID_LEN];
+    u_char holding_time[2];
+    u_char pdu_len[2];
+    u_char circuit_id;
+};
 
-void
-isoclns_print(const u_char *p, u_int length, u_int caplen,
+struct isis_lsp_header {
+    u_char pdu_len[2];
+    u_char remaining_lifetime[2];
+    u_char lsp_id[LSP_ID_LEN];
+    u_char sequence_number[4];
+    u_char checksum[2];
+    u_char typeblock;
+};
+
+struct isis_csnp_header {
+    u_char pdu_len[2];
+    u_char source_id[NODE_ID_LEN];
+    u_char start_lsp_id[LSP_ID_LEN];
+    u_char end_lsp_id[LSP_ID_LEN];
+};
+
+struct isis_psnp_header {
+    u_char pdu_len[2];
+    u_char source_id[NODE_ID_LEN];
+};
+
+struct isis_tlv_lsp {
+    u_char remaining_lifetime[2];
+    u_char lsp_id[LSP_ID_LEN];
+    u_char sequence_number[4];
+    u_char checksum[2];
+};
+
+#define ISIS_COMMON_HEADER_SIZE (sizeof(struct isis_common_header))
+#define ISIS_IIH_LAN_HEADER_SIZE (sizeof(struct isis_iih_lan_header))
+#define ISIS_IIH_PTP_HEADER_SIZE (sizeof(struct isis_iih_ptp_header))
+#define ISIS_LSP_HEADER_SIZE (sizeof(struct isis_lsp_header))
+#define ISIS_CSNP_HEADER_SIZE (sizeof(struct isis_csnp_header))
+#define ISIS_PSNP_HEADER_SIZE (sizeof(struct isis_psnp_header))
+
+void isoclns_print(const u_char *p, u_int length, u_int caplen,
              const u_char *esrc, const u_char *edst)
 {
+       u_char pdu_type;
+       const struct isis_common_header *header;
+
+       header = (const struct isis_common_header *)p;
+       pdu_type = header->pdu_type & PDU_TYPE_MASK;
+
        if (caplen < 1) {
                printf("[|iso-clns] ");
-               if (!eflag)
+               if (!eflag && esrc != NULL && edst != NULL)
                        printf("%s > %s",
                               etheraddr_string(esrc),
                               etheraddr_string(edst));
@@ -68,51 +459,47 @@ isoclns_print(const u_char *p, u_int length, u_int caplen,
 
        switch (*p) {
 
-       case CLNS:
-               /* esis_print(&p, &length); */
-               printf("iso-clns");
-               if (!eflag)
-                       (void)printf(" %s > %s",
+       case NLPID_CLNS:
+               (void)printf("CLNS(%d)", length);
+               if (!eflag && esrc != NULL && edst != NULL)
+                       (void)printf(", %s > %s",
                                     etheraddr_string(esrc),
                                     etheraddr_string(edst));
                break;
 
-       case ESIS:
-               printf("iso-esis");
-               if (!eflag)
-                       (void)printf(" %s > %s",
+       case NLPID_ESIS:
+               (void)printf("ESIS");
+               if (!eflag && esrc != NULL && edst != NULL)
+                       (void)printf(", %s > %s",
                                     etheraddr_string(esrc),
                                     etheraddr_string(edst));
                esis_print(p, length);
                return;
 
-       case ISIS:
-               printf("iso-isis");
-               if (!eflag)
-                       (void)printf(" %s > %s",
-                                    etheraddr_string(esrc),
-                                    etheraddr_string(edst));
-               /* isis_print(&p, &length); */
-               (void)printf(" len=%d ", length);
-               if (caplen > 1)
+       case NLPID_ISIS:
+               (void)printf("ISIS(%d)", length);
+               if (!eflag && esrc != NULL && edst != NULL)
+                       (void)printf(", %s > %s",
+                            etheraddr_string(esrc),
+                            etheraddr_string(edst));
+               if (!isis_print(p, length))
                        default_print_unaligned(p, caplen);
                break;
 
-       case NULLNS:
-               printf("iso-nullns");
-               if (!eflag)
-                       (void)printf(" %s > %s",
+       case NLPID_NULLNS:
+               (void)printf("ISO NULLNS(%d)", length);
+               if (!eflag && esrc != NULL && edst != NULL)
+                       (void)printf(", %s > %s",
                                     etheraddr_string(esrc),
                                     etheraddr_string(edst));
                break;
 
        default:
-               printf("iso-clns %02x", p[0]);
-               if (!eflag)
-                       (void)printf(" %s > %s",
+               (void)printf("CLNS %02x(%d)", p[0], length);
+               if (!eflag && esrc != NULL && edst != NULL)
+                       (void)printf(", %s > %s",
                                     etheraddr_string(esrc),
                                     etheraddr_string(edst));
-               (void)printf(" len=%d ", length);
                if (caplen > 1)
                        default_print_unaligned(p, caplen);
                break;
@@ -135,18 +522,18 @@ static void
 esis_print(const u_char *p, u_int length)
 {
        const u_char *ep;
-       int li = p[1];
-       const struct esis_hdr *eh = (const struct esis_hdr *) &p[2];
-       u_char cksum[2];
-       u_char off[2];
+       u_int li;
+       const struct esis_hdr *eh;
 
-       if (length == 2) {
+       if (length <= 2) {
                if (qflag)
                        printf(" bad pkt!");
                else
                        printf(" no header at all!");
                return;
        }
+       li = p[1];
+       eh = (const struct esis_hdr *) &p[2];
        ep = p + li;
        if (li > length) {
                if (qflag)
@@ -183,11 +570,10 @@ esis_print(const u_char *p, u_int length)
                printf(" type %d", eh->type & 0x1f);
                break;
        }
-       off[0] = eh->cksum[0];
-       off[1] = eh->cksum[1];
-       if (vflag && osi_cksum(p, li, eh->cksum, cksum, off)) {
-               printf(" bad cksum (got %02x%02x want %02x%02x)",
-                      eh->cksum[1], eh->cksum[0], cksum[1], cksum[0]);
+       if (vflag && osi_cksum(p, li)) {
+               printf(" bad cksum (got 0x%02x%02x)",
+                      eh->cksum[1], eh->cksum[0]);
+               default_print(p, length);
                return;
        }
        if (eh->version != 1) {
@@ -204,7 +590,7 @@ esis_print(const u_char *p, u_int length)
                dst = p; p += *p + 1;
                if (p > snapend)
                        return;
-               printf(" %s", isonsap_string(dst));
+               printf("\n\t\t\t %s", isonsap_string(dst));
                snpa = p; p += *p + 1;
                is = p;   p += *p + 1;
                if (p > snapend)
@@ -235,7 +621,8 @@ esis_print(const u_char *p, u_int length)
                }
                if (p > snapend)
                        return;
-               printf(" %s", isonsap_string(is));
+               if (!qflag)
+                       printf("\n\t\t\t %s", isonsap_string(is));
                li = ep - p;
                break;
        }
@@ -250,7 +637,7 @@ esis_print(const u_char *p, u_int length)
        }
        if (vflag)
                while (p < ep && li) {
-                       int op, opli;
+                       u_int op, opli;
                        const u_char *q;
 
                        if (snapend - p < 2)
@@ -276,42 +663,1436 @@ esis_print(const u_char *p, u_int length)
                                continue;
                        }
                        printf (" %d:<", op);
-                       while (--opli >= 0)
+                       while (opli-- > 0)
                                printf("%02x", *q++);
                        printf (">");
                }
 }
 
+/* allocate space for the following string
+ * xx.xxxx.xxxx.xxxx.xxxx.xxxx.xxxx
+ * 32 bytes plus one termination byte */
+static char *
+print_nsap(register const u_char *cp, register int length)
+{
+       int i;
+       static char nsap[33];
+        char *pos = nsap;
+
+        if (length==0) {
+               *(pos) = '0';
+                *(pos+1) = '\0';
+                return (nsap);
+        }
+
+       for (i = 0; i < length; i++) {
+               if (!TTEST2(*cp, 1))
+                       return (0);
+               pos+=sprintf(pos, "%02x", *cp++);
+               if (((i & 1) == 0) && (i + 1 < length)) {
+                       pos+=sprintf(pos, ".");
+               }
+       }
+        *(pos) = '\0';
+       return (nsap);
+}
+
+/* allocate space for the following string
+ * xxxx.xxxx.xxxx
+ * 14 bytes plus one termination byte */
+static char *
+isis_print_sysid(const u_char *cp, int sysid_len)
+{
+       int i;
+       static char sysid[15];
+        char *pos = sysid;
+
+       for (i = 1; i <= sysid_len; i++) {
+               if (!TTEST2(*cp, 1))
+                       return (0);
+               pos+=sprintf(pos, "%02x", *cp++);
+               if ((i==2)^(i==4)) {
+                       pos+=sprintf(pos, ".");
+               }
+       }
+        *(pos) = '\0';
+       return (sysid);
+}
+
+
+/* allocate space for the following string
+ * xxxx.xxxx.xxxx.yy
+ * 17 bytes plus one termination byte */
+static char *
+isis_print_nodeid(const u_char *cp)
+{
+       int i;
+       static char nodeid[18];
+        char *pos = nodeid;
+
+       for (i = 1; i <= 7; i++) {
+               if (!TTEST2(*cp, 1))
+                       return (0);
+               pos+=sprintf(pos, "%02x", *cp++);
+               if ((i & 1) == 0) {
+                       pos+=sprintf(pos, ".");
+               }
+       }
+        *(pos) = '\0';
+       return (nodeid);
+}
+
+/* allocate space for the following string
+ * xxxx.xxxx.xxxx.yy-zz
+ * 20 bytes plus one termination byte */
+static char *
+isis_print_lspid(const u_char *cp)
+{
+       int i;
+       static char lspid[21];
+        char *pos = lspid;
+
+       for (i = 1; i <= 7; i++) {
+               pos+=sprintf(pos, "%02x", *cp++);
+               if ((i & 1) == 0)
+                       pos+=sprintf(pos, ".");
+       }
+       pos+=sprintf(pos, "-%02x", *cp);
+        return (lspid);
+}
+
+/*
+ *  this is a generic routine for printing unknown data;
+ *  as it is called from various places (TLV and subTLV parsing routines)
+ *  we pass on the linefeed plus indentation string to
+ *  get a proper output - returns 0 on error
+ */
+
 static int
-osi_cksum(register const u_char *p, register u_int len,
-         const u_char *toff, u_char *cksum, u_char *off)
+isis_print_unknown_data(const u_char *cp,const char *lf,int len)
 {
-       int x, y, f = (len - ((toff - p) + 1));
-       int32_t c0 = 0, c1 = 0;
+        int i;
+
+       printf("%s0x0000: ",lf);
+       for(i=0;i<len;i++) {
+           if (!TTEST2(*(cp+i), 1))
+             goto trunctlv;
+           printf("%02x",*(cp+i));
+           if (i%2)
+               printf(" ");
+           if (i/16!=(i+1)/16) {
+               if (i<(len-1))
+                   printf("%s0x%04x: ",lf,i);
+           }
+       }
+       return(1); /* everything is ok */
+
+trunctlv:
+    printf("%spacket exceeded snapshot",lf);
+    return(0);
+
+}
+
+/* print the 4-byte metric block which is common found in the old-style TLVs */
+
+static int
+isis_print_metric_block (const struct isis_metric_block *isis_metric_block)
+{
+    printf(", Default Metric: %d, %s",
+           ISIS_LSP_TLV_METRIC_VALUE(isis_metric_block->metric_default),
+           ISIS_LSP_TLV_METRIC_IE(isis_metric_block->metric_default) ? "External" : "Internal");
+    if (!ISIS_LSP_TLV_METRIC_SUPPORTED(isis_metric_block->metric_delay))
+        printf("\n\t\t\t  Delay Metric: %d, %s",
+               ISIS_LSP_TLV_METRIC_VALUE(isis_metric_block->metric_delay),
+               ISIS_LSP_TLV_METRIC_IE(isis_metric_block->metric_delay) ? "External" : "Internal");
+    if (!ISIS_LSP_TLV_METRIC_SUPPORTED(isis_metric_block->metric_expense))
+        printf("\n\t\t\t  Expense Metric: %d, %s",
+               ISIS_LSP_TLV_METRIC_VALUE(isis_metric_block->metric_expense),
+               ISIS_LSP_TLV_METRIC_IE(isis_metric_block->metric_expense) ? "External" : "Internal");
+    if (!ISIS_LSP_TLV_METRIC_SUPPORTED(isis_metric_block->metric_error))
+        printf("\n\t\t\t  Error Metric: %d, %s",
+               ISIS_LSP_TLV_METRIC_VALUE(isis_metric_block->metric_error),
+               ISIS_LSP_TLV_METRIC_IE(isis_metric_block->metric_error) ? "External" : "Internal");
+
+    return(1); /* everything is ok */
+}
+
+static int
+isis_print_tlv_ip_reach (const u_char *cp, int length)
+{
+       u_int bitmasks[33] = {
+               0x00000000,
+               0x80000000, 0xc0000000, 0xe0000000, 0xf0000000,
+               0xf8000000, 0xfc000000, 0xfe000000, 0xff000000,
+               0xff800000, 0xffc00000, 0xffe00000, 0xfff00000,
+               0xfff80000, 0xfffc0000, 0xfffe0000, 0xffff0000,
+               0xffff8000, 0xffffc000, 0xffffe000, 0xfffff000,
+               0xfffff800, 0xfffffc00, 0xfffffe00, 0xffffff00,
+               0xffffff80, 0xffffffc0, 0xffffffe0, 0xfffffff0,
+               0xfffffff8, 0xfffffffc, 0xfffffffe, 0xffffffff
+       };
+       u_int mask;
+       int prefix_len;
+       const struct isis_tlv_ip_reach *tlv_ip_reach;
+
+       tlv_ip_reach = (const struct isis_tlv_ip_reach *)cp;
+
+       while (length > 0) {
+               if (length < sizeof(*tlv_ip_reach)) {
+                       printf("short IPv4 reachability (%d vs %lu)", length,
+                           (unsigned long)sizeof(*tlv_ip_reach));
+                       return (0);
+               }
+
+               if (!TTEST(*tlv_ip_reach))
+                   return (0);
+
+               mask = EXTRACT_32BITS(tlv_ip_reach->mask);
+               prefix_len = 0;
+
+                /* lets see if we can transform the mask into a prefixlen */
+               while (prefix_len <= 33) {
+                       if (bitmasks[prefix_len++] == mask) {
+                               prefix_len--;
+                               break;
+                       }
+               }
+
+               /*
+                * 34 indicates no match -> must be a discontiguous netmask
+                * lets dump the mask, otherwise print the prefix_len
+                */
+               if (prefix_len == 34)
+                       printf("\n\t\t\tIPv4 prefix: %s mask %s",
+                              ipaddr_string((tlv_ip_reach->prefix)),
+                              ipaddr_string((tlv_ip_reach->mask)));
+               else
+                       printf("\n\t\t\tIPv4 prefix: %s/%u",
+                              ipaddr_string((tlv_ip_reach->prefix)),
+                              prefix_len);
+
+               printf("\n\t\t\t  Default Metric: %02d, %s, Distribution: %s",
+                   ISIS_LSP_TLV_METRIC_VALUE(tlv_ip_reach->isis_metric_block.metric_default),
+                   ISIS_LSP_TLV_METRIC_IE(tlv_ip_reach->isis_metric_block.metric_default) ? "External" : "Internal",
+                   ISIS_LSP_TLV_METRIC_UPDOWN(tlv_ip_reach->isis_metric_block.metric_default) ? "down" : "up");
+
+               if (!ISIS_LSP_TLV_METRIC_SUPPORTED(tlv_ip_reach->isis_metric_block.metric_delay))
+                       printf("\n\t\t\t  Delay Metric: %02d, %s",
+                           ISIS_LSP_TLV_METRIC_VALUE(tlv_ip_reach->isis_metric_block.metric_delay),
+                           ISIS_LSP_TLV_METRIC_IE(tlv_ip_reach->isis_metric_block.metric_delay) ? "External" : "Internal");
+
+               if (!ISIS_LSP_TLV_METRIC_SUPPORTED(tlv_ip_reach->isis_metric_block.metric_expense))
+                       printf("\n\t\t\t  Expense Metric: %02d, %s",
+                           ISIS_LSP_TLV_METRIC_VALUE(tlv_ip_reach->isis_metric_block.metric_expense),
+                           ISIS_LSP_TLV_METRIC_IE(tlv_ip_reach->isis_metric_block.metric_expense) ? "External" : "Internal");
+
+               if (!ISIS_LSP_TLV_METRIC_SUPPORTED(tlv_ip_reach->isis_metric_block.metric_error))
+                       printf("\n\t\t\t  Error Metric: %02d, %s",
+                           ISIS_LSP_TLV_METRIC_VALUE(tlv_ip_reach->isis_metric_block.metric_error),
+                           ISIS_LSP_TLV_METRIC_IE(tlv_ip_reach->isis_metric_block.metric_error) ? "External" : "Internal");
+
+               length -= sizeof(struct isis_tlv_ip_reach);
+               tlv_ip_reach++;
+       }
+       return (1);
+}
+
+/*
+ * this is the common IP-REACH subTLV decoder it is called
+ * from various EXTD-IP REACH TLVs (135,235,236,237)
+ */
+
+static int
+isis_print_ip_reach_subtlv (const u_char *tptr,int subt,int subl,const char *lf) {
+
+        switch(subt) {
+        case SUBTLV_IP_REACH_ADMIN_TAG32:
+            if (!TTEST2(*tptr,4))
+                goto trunctlv;
+            printf("%s32-Bit Administrative tag: 0x%08x",
+                   lf,
+                   EXTRACT_32BITS(tptr));
+            break;
+        case SUBTLV_IP_REACH_ADMIN_TAG64:
+            if (!TTEST2(*tptr,8))
+                goto trunctlv;
+            printf("%s64-Bit Administrative tag: 0x%08x%08x",
+                   lf,
+                   EXTRACT_32BITS(tptr),
+                   EXTRACT_32BITS(tptr+4));
+            break;
+        default:
+            printf("%sunknown subTLV, type %d, length %d",
+                   lf,
+                   subt,
+                   subl);
+            if(!isis_print_unknown_data(tptr,"\n\t\t\t    ",
+                                       subl))
+                return(0);
+            break;
+        }
+        return(1);
+
+trunctlv:
+    printf("%spacket exceeded snapshot",lf);
+    return(0);
+}
+
+/*
+ * this is the common IS-REACH subTLV decoder it is called
+ * from various EXTD-IS REACH TLVs (22,24,222)
+ */
+
+static int
+isis_print_is_reach_subtlv (const u_char *tptr,int subt,int subl,const char *lf) {
+
+        int i,j;
+        float bw; /* copy buffer for several subTLVs */
+
+        switch(subt) {
+        case SUBTLV_EXT_IS_REACH_ADMIN_GROUP:
+            if (!TTEST2(*tptr,4))
+                goto trunctlv;
+            printf("%sAdministrative groups: 0x%08x",
+                   lf,
+                   EXTRACT_32BITS(tptr));
+            break;
+        case SUBTLV_EXT_IS_REACH_LINK_LOCAL_ID:
+            if (!TTEST2(*tptr,4))
+                goto trunctlv;
+            printf("%sLink Local Identifier: 0x%08x",
+                   lf,
+                   EXTRACT_32BITS(tptr));
+            break;
+        case SUBTLV_EXT_IS_REACH_LINK_REMOTE_ID:
+            if (!TTEST2(*tptr,4))
+                goto trunctlv;
+            printf("%sLink Remote Identifier: 0x%08x",
+                   lf,
+                   EXTRACT_32BITS(tptr));
+            break;
+        case SUBTLV_EXT_IS_REACH_MAX_LINK_BW :
+            if (!TTEST2(*tptr,4))
+                goto trunctlv;
+            j = EXTRACT_32BITS(tptr);
+            memcpy (&bw, &j, 4);
+            printf("%sMaximum link bandwidth : %.3f Mbps",
+                   lf,
+                   bw*8/1000000 );
+            break;
+        case SUBTLV_EXT_IS_REACH_RESERVABLE_BW :
+            if (!TTEST2(*tptr,4))
+                goto trunctlv;
+            j = EXTRACT_32BITS(tptr);
+            memcpy (&bw, &j, 4);
+            printf("%sReservable link bandwidth: %.3f Mbps",
+                   lf,
+                   bw*8/1000000  );
+            break;
+        case SUBTLV_EXT_IS_REACH_UNRESERVED_BW :
+            printf("%sUnreserved bandwidth:",lf);
+            for (i = 0; i < 8; i++) {
+                if (!TTEST2(*(tptr+i*4),4))
+                    goto trunctlv;
+                j = EXTRACT_32BITS(tptr);
+                memcpy (&bw, &j, 4);
+                printf("%s  priority level %d: %.3f Mbps",
+                       lf,
+                       i,
+                       bw*8/1000000 );
+            }
+            break;
+        case SUBTLV_EXT_IS_REACH_TE_METRIC:
+            if (!TTEST2(*tptr,3))
+                goto trunctlv;
+            printf("%sTraffic Engineering Metric: %d",
+                   lf,
+                   EXTRACT_24BITS(tptr));
+            break;
+        case SUBTLV_EXT_IS_REACH_IPV4_INTF_ADDR:
+            if (!TTEST2(*tptr,4))
+                goto trunctlv;
+            printf("%sIPv4 interface address: %s",
+                   lf,
+                   ipaddr_string(tptr));
+            break;
+        case SUBTLV_EXT_IS_REACH_IPV4_NEIGHBOR_ADDR:
+            if (!TTEST2(*tptr,4))
+                goto trunctlv;
+            printf("%sIPv4 neighbor address: %s",
+                   lf,
+                   ipaddr_string(tptr));
+            break;
+        case SUBTLV_EXT_IS_REACH_LINK_PROTECTION_TYPE:
+            if (!TTEST2(*tptr,2))
+                goto trunctlv;
+            i = 0;
+            j = (ISIS_8BIT_MASK(*tptr)); /* fetch the typecode and make sure
+                                            that no high-order LSBs are set */
+            printf("%sLink Protection Type: %s",
+                   lf,
+                   (j) ? "" : "none" );
+            /* scan through the bits until the typecode is zero */
+            while(!j) {
+                printf("%s", isis_gmpls_link_prot_values[i]);
+                j=j>>1;
+                if (j) /*any other bit set ?*/
+                    printf(", ");
+                i++;
+            }
+            printf(", Priority %u", *(tptr+1));
+            break;
+        case SUBTLV_EXT_IS_REACH_INTF_SW_CAP_DESCR:
+            printf("%sInterface Switching Capability",lf);
+
+            if (!TTEST2(*tptr,1))
+                goto trunctlv;
+            printf("%s  Interface Switching Capability:%s",
+                   lf,
+                   tok2str(isis_gmpls_sw_cap_values, "Unknown", *(tptr)));
+
+            if (!TTEST2(*(tptr+1),1))
+                goto trunctlv;
+            printf(", LSP Encoding: %s",
+                   tok2str(isis_gmpls_lsp_enc_values, "Unknown", *(tptr+1)));
+
+            if (!TTEST2(*(tptr+2),2)) /* skip 2 res. bytes */
+                goto trunctlv;
+
+            printf("%s  Max LSP Bandwidth:",lf);
+            for (i = 0; i < 8; i++) {
+                if (!TTEST2(*(tptr+(i*4)+4),4))
+                    goto trunctlv;
+                j = EXTRACT_32BITS(tptr);
+                memcpy (&bw, &j, 4);
+                printf("%s    priority level %d: %.3f Mbps",
+                       lf,
+                       i,
+                       bw*8/1000000 );
+            }
+            subl-=36;
+            /* there is some optional stuff left to decode but this is as of yet
+               not specified so just lets hexdump what is left */
+            if(subl>0){
+                if(!isis_print_unknown_data(tptr,"\n\t\t\t    ",
+                                           subl-36))
+                    return(0);
+            }
+            break;
+        case 250:
+        case 251:
+        case 252:
+        case 253:
+        case 254:
+            printf("%sReserved for cisco specific extensions, type %d, length %d",
+                   lf,
+                   subt,
+                   subl);
+            break;
+        case 255:
+            printf("%sReserved for future expansion, type %d, length %d",
+                   lf,
+                   subt,
+                   subl);
+            break;
+        default:
+            printf("%sunknown subTLV, type %d, length %d",
+                   lf,
+                   subt,
+                   subl);
+            if(!isis_print_unknown_data(tptr,"\n\t\t\t    ",
+                                       subl))
+                return(0);
+            break;
+        }
+        return(1);
+
+trunctlv:
+    printf("%spacket exceeded snapshot",lf);
+    return(0);
+}
+
+
+/*
+ * isis_print
+ * Decode IS-IS packets.  Return 0 on error.
+ */
+
+static int isis_print (const u_char *p, u_int length)
+{
+    const struct isis_common_header *header;
+
+    const struct isis_iih_lan_header *header_iih_lan;
+    const struct isis_iih_ptp_header *header_iih_ptp;
+    const struct isis_lsp_header *header_lsp;
+    const struct isis_csnp_header *header_csnp;
+    const struct isis_psnp_header *header_psnp;
+
+    const struct isis_tlv_lsp *tlv_lsp;
+    const struct isis_tlv_ptp_adj *tlv_ptp_adj;
+    const struct isis_tlv_is_reach *tlv_is_reach;
+    const struct isis_tlv_es_reach *tlv_es_reach;
+
+    u_char pdu_type, max_area, id_length, type, len, tmp, alen, lan_alen, prefix_len, subl, subt, tslen;
+    const u_char *optr, *pptr, *tptr;
+    u_short packet_len,pdu_len,time_remain;
+    u_int i,j,bit_length,byte_length,metric,ra,rr;
+    u_char prefix[4]; /* copy buffer for ipv4 prefixes */
+#ifdef INET6
+    u_char prefix6[16]; /* copy buffer for ipv6 prefixes */
+#endif
+    packet_len=length;
+    optr = p; /* initialize the _o_riginal pointer to the packet start -
+               need it for parsing the checksum TLV */
+    header = (const struct isis_common_header *)p;
+    TCHECK(*header);
+    pptr = p+(ISIS_COMMON_HEADER_SIZE);
+    header_iih_lan = (const struct isis_iih_lan_header *)pptr;
+    header_iih_ptp = (const struct isis_iih_ptp_header *)pptr;
+    header_lsp = (const struct isis_lsp_header *)pptr;
+    header_csnp = (const struct isis_csnp_header *)pptr;
+    header_psnp = (const struct isis_psnp_header *)pptr;
+
+    /*
+     * Sanity checking of the header.
+     */
+    if (header->nlpid != NLPID_ISIS) {
+       printf(", coding error!");
+       return (0);
+    }
+
+    if (header->version != ISIS_VERSION) {
+       printf(", version %d packet not supported", header->version);
+       return (0);
+    }
+
+    if ((header->id_length != SYSTEM_ID_LEN) && (header->id_length != 0)) {
+       printf(", system ID length of %d is not supported",
+              header->id_length);
+       return (0);
+    }
+
+    if (header->pkt_version != ISIS_VERSION) {
+       printf(", version %d packet not supported", header->pkt_version);
+       return (0);
+    }
+
+    max_area = header->max_area;
+    switch(max_area) {
+    case 0:
+       max_area = 3;    /* silly shit */
+       break;
+    case 255:
+       printf(", bad packet -- 255 areas");
+       return (0);
+    default:
+       break;
+    }
+
+    id_length = header->id_length;
+    switch(id_length) {
+    case 0:
+        id_length = 6;  /* silly shit again */
+       break;
+    case 1:              /* 1-8 are valid sys-ID lenghts */
+    case 2:
+    case 3:
+    case 4:
+    case 5:
+    case 6:
+    case 7:
+    case 8:
+        break;
+    case 255:
+        id_length = 0;   /* entirely useless */
+       break;
+    default:
+       printf(", bad packet -- illegal sys-ID length (%u)", id_length);
+       return (0);
+       break;
+    }
+
+    printf(", hlen: %u, v: %u, sys-id-len: %u (%u), max-area: %u (%u)",
+           header->fixed_len,
+           header->version,
+          id_length,
+          header->id_length,
+           max_area,
+           header->max_area);
+
+    pdu_type=header->pdu_type;
+
+    /* first lets see if we know the PDU name*/
+    printf(", %s",
+           tok2str(isis_pdu_values,
+                   "unknown PDU, type %d",
+                   pdu_type));
+
+    switch (pdu_type) {
+
+    case L1_LAN_IIH:
+    case L2_LAN_IIH:
+       if (header->fixed_len != (ISIS_COMMON_HEADER_SIZE+ISIS_IIH_LAN_HEADER_SIZE)) {
+           printf(", bogus fixed header length %u should be %lu",
+                  header->fixed_len, (unsigned long)ISIS_IIH_LAN_HEADER_SIZE);
+           return (0);
+       }
+
+       pdu_len=EXTRACT_16BITS(header_iih_lan->pdu_len);
+       if (packet_len>pdu_len) {
+         packet_len=pdu_len; /* do TLV decoding as long as it makes sense */
+         length=pdu_len;
+       }
+
+       TCHECK(*header_iih_lan);
+       printf("\n\t\t  source-id: %s,  holding time: %u, %s",
+               isis_print_sysid(header_iih_lan->source_id,SYSTEM_ID_LEN),
+               EXTRACT_16BITS(header_iih_lan->holding_time),
+               tok2str(isis_iih_circuit_type_values,
+                       "unknown circuit type 0x%02x",
+                       header_iih_lan->circuit_type));
+
+       printf("\n\t\t  lan-id:    %s, Priority: %u, PDU length: %u",
+               isis_print_nodeid(header_iih_lan->lan_id),
+               (header_iih_lan->priority) & PRIORITY_MASK,
+               pdu_len);
+
+       packet_len -= (ISIS_COMMON_HEADER_SIZE+ISIS_IIH_LAN_HEADER_SIZE);
+       pptr = p + (ISIS_COMMON_HEADER_SIZE+ISIS_IIH_LAN_HEADER_SIZE);
+       break;
+
+    case PTP_IIH:
+       if (header->fixed_len != (ISIS_COMMON_HEADER_SIZE+ISIS_IIH_PTP_HEADER_SIZE)) {
+           printf(", bogus fixed header length %u should be %lu",
+                  header->fixed_len, (unsigned long)ISIS_IIH_PTP_HEADER_SIZE);
+           return (0);
+       }
+
+       pdu_len=EXTRACT_16BITS(header_iih_ptp->pdu_len);
+       if (packet_len>pdu_len) {
+         packet_len=pdu_len; /* do TLV decoding as long as it makes sense */
+         length=pdu_len;
+       }
+
+       TCHECK(*header_iih_ptp);
+       printf("\n\t\t  source-id: %s, holding time: %us, circuit-id: 0x%02x, %s, PDU length: %u",
+               isis_print_sysid(header_iih_ptp->source_id,SYSTEM_ID_LEN),
+               EXTRACT_16BITS(header_iih_ptp->holding_time),
+               header_iih_ptp->circuit_id,
+               tok2str(isis_iih_circuit_type_values,
+                       "unknown circuit type 0x%02x",
+                       header_iih_ptp->circuit_type),
+               pdu_len);
+
+       packet_len -= (ISIS_COMMON_HEADER_SIZE+ISIS_IIH_PTP_HEADER_SIZE);
+       pptr = p + (ISIS_COMMON_HEADER_SIZE+ISIS_IIH_PTP_HEADER_SIZE);
+       break;
+
+    case L1_LSP:
+    case L2_LSP:
+       if (header->fixed_len != (ISIS_COMMON_HEADER_SIZE+ISIS_LSP_HEADER_SIZE)) {
+           printf(", bogus fixed header length %u should be %lu",
+                  header->fixed_len, (unsigned long)ISIS_LSP_HEADER_SIZE);
+           return (0);
+       }
+
+       pdu_len=EXTRACT_16BITS(header_lsp->pdu_len);
+       if (packet_len>pdu_len) {
+         packet_len=pdu_len; /* do TLV decoding as long as it makes sense */
+         length=pdu_len;
+       }
+
+       TCHECK(*header_lsp);
+       printf("\n\t\t  lsp-id: %s, seq: 0x%08x, lifetime: %5us",
+               isis_print_lspid(header_lsp->lsp_id),
+               EXTRACT_32BITS(header_lsp->sequence_number),
+               EXTRACT_16BITS(header_lsp->remaining_lifetime));
+        /* verify the checksum -
+         * checking starts at the lsp-id field
+         * which is 12 bytes after the packet start*/
+       printf("\n\t\t  chksum: 0x%04x (%s), PDU length: %u",
+               EXTRACT_16BITS(header_lsp->checksum),
+               (osi_cksum(optr+12, length-12)) ? "incorrect" : "correct",
+               pdu_len);
+
+       printf(", %s", ISIS_MASK_LSP_OL_BIT(header_lsp->typeblock) ? "Overload bit set, " : "");
+
+       if (ISIS_MASK_LSP_ATT_BITS(header_lsp->typeblock)) {
+           printf("%s", ISIS_MASK_LSP_ATT_DEFAULT_BIT(header_lsp->typeblock) ? "default " : "");
+           printf("%s", ISIS_MASK_LSP_ATT_DELAY_BIT(header_lsp->typeblock) ? "delay " : "");
+           printf("%s", ISIS_MASK_LSP_ATT_EXPENSE_BIT(header_lsp->typeblock) ? "expense " : "");
+           printf("%s", ISIS_MASK_LSP_ATT_ERROR_BIT(header_lsp->typeblock) ? "error " : "");
+           printf("ATT bit set, ");
+       }
+       printf("%s", ISIS_MASK_LSP_PARTITION_BIT(header_lsp->typeblock) ? "P bit set, " : "");
+       printf("%s", tok2str(isis_lsp_istype_values,"Unknown(0x%x)",ISIS_MASK_LSP_ISTYPE_BITS(header_lsp->typeblock)));
+
+       packet_len -= (ISIS_COMMON_HEADER_SIZE+ISIS_LSP_HEADER_SIZE);
+       pptr = p + (ISIS_COMMON_HEADER_SIZE+ISIS_LSP_HEADER_SIZE);
+       break;
+
+    case L1_CSNP:
+    case L2_CSNP:
+       if (header->fixed_len != (ISIS_COMMON_HEADER_SIZE+ISIS_CSNP_HEADER_SIZE)) {
+           printf(", bogus fixed header length %u should be %lu",
+                  header->fixed_len, (unsigned long)ISIS_CSNP_HEADER_SIZE);
+           return (0);
+       }
+
+       pdu_len=EXTRACT_16BITS(header_csnp->pdu_len);
+       if (packet_len>pdu_len) {
+         packet_len=pdu_len; /* do TLV decoding as long as it makes sense */
+         length=pdu_len;
+       }
+
+       TCHECK(*header_csnp);
+       printf("\n\t\t  source-id:    %s, PDU length: %u",
+               isis_print_nodeid(header_csnp->source_id),
+               pdu_len);
+       printf("\n\t\t  start lsp-id: %s",
+               isis_print_lspid(header_csnp->start_lsp_id));
+       printf("\n\t\t  end lsp-id:   %s",
+               isis_print_lspid(header_csnp->end_lsp_id));
+
+       packet_len -= (ISIS_COMMON_HEADER_SIZE+ISIS_CSNP_HEADER_SIZE);
+       pptr = p + (ISIS_COMMON_HEADER_SIZE+ISIS_CSNP_HEADER_SIZE);
+        break;
+
+    case L1_PSNP:
+    case L2_PSNP:
+       if (header->fixed_len != (ISIS_COMMON_HEADER_SIZE+ISIS_PSNP_HEADER_SIZE)) {
+           printf("- bogus fixed header length %u should be %lu",
+                  header->fixed_len, (unsigned long)ISIS_PSNP_HEADER_SIZE);
+           return (0);
+       }
+
+       pdu_len=EXTRACT_16BITS(header_psnp->pdu_len);
+       if (packet_len>pdu_len) {
+         packet_len=pdu_len; /* do TLV decoding as long as it makes sense */
+         length=pdu_len;
+       }
+
+       TCHECK(*header_psnp);
+       printf("\n\t\t  source-id:    %s",
+               isis_print_nodeid(header_psnp->source_id));
+
+       packet_len -= (ISIS_COMMON_HEADER_SIZE+ISIS_PSNP_HEADER_SIZE);
+       pptr = p + (ISIS_COMMON_HEADER_SIZE+ISIS_PSNP_HEADER_SIZE);
+       break;
+
+    default:
+       if(!isis_print_unknown_data(pptr,"\n\t\t  ",length))
+           return(0);
+       return (0);
+    }
+
+    /*
+     * Now print the TLV's.
+     */
+
+    while (packet_len >= 2) {
+        if (pptr == snapend) {
+           return (1);
+        }
+
+       if (!TTEST2(*pptr, 2)) {
+           printf("\n\t\t\t packet exceeded snapshot (%ld) bytes",
+                 (long)(pptr-snapend));
+           return (1);
+       }
+       type = *pptr++;
+       len = *pptr++;
+        tmp =len; /* copy temporary len & pointer to packet data */
+        tptr = pptr;
+       packet_len -= 2;
+       if (len > packet_len) {
+           break;
+       }
+
+        /* first lets see if we know the TLVs name*/
+       printf("\n\t\t    %s TLV #%u, length: %u",
+               tok2str(isis_tlv_values,
+                       "unknown",
+                       type),
+               type,
+               len);
+
+        /* now check if we have a decoder otherwise do a hexdump at the end*/
+       switch (type) {
+       case TLV_AREA_ADDR:
+           if (!TTEST2(*tptr, 1))
+               goto trunctlv;
+           alen = *tptr++;
+           while (tmp && alen < tmp) {
+               printf("\n\t\t\tArea address (%u): %s",
+                       alen,
+                       print_nsap(tptr, alen));
+               tptr += alen;
+               tmp -= alen + 1;
+               if (tmp==0) /* if this is the last area address do not attemt a boundary check */
+                 break;
+               if (!TTEST2(*tptr, 1))
+                   goto trunctlv;
+               alen = *tptr++;
+           }
+           break;
+       case TLV_ISNEIGH:
+           while (tmp >= ETHER_ADDR_LEN) {
+            if (!TTEST2(*tptr, ETHER_ADDR_LEN))
+               goto trunctlv;
+            printf("\n\t\t\tIS Neighbor: %s",isis_print_sysid(tptr,ETHER_ADDR_LEN));
+            tmp -= ETHER_ADDR_LEN;
+            tptr += ETHER_ADDR_LEN;
+           }
+           break;
+
+        case TLV_ISNEIGH_VARLEN:
+            if (!TTEST2(*tptr, 1))
+               goto trunctlv;
+           lan_alen = *tptr++; /* LAN adress length */
+            tmp --;
+            printf("\n\t\t\tLAN address length %u bytes ",lan_alen);
+           while (tmp >= lan_alen) {
+            if (!TTEST2(*tptr, lan_alen))
+               goto trunctlv;
+            printf("\n\t\t\tIS Neighbor: %s",isis_print_sysid(tptr,lan_alen));
+            tmp -= lan_alen;
+            tptr +=lan_alen;
+            }
+            break;
+
+       case TLV_PADDING:
+           break;
+
+        case TLV_MT_IS_REACH:
+            while (tmp>0) {
+                if (!TTEST2(*tptr, 2))
+                   goto trunctlv;
+                printf("\n\t\t\t%s",
+                       tok2str(isis_mt_values,
+                               "Reserved for IETF Consensus",
+                               ISIS_MASK_MTID(EXTRACT_16BITS(tptr))));
+
+               printf(" Topology (0x%03x)",
+                       ISIS_MASK_MTID(EXTRACT_16BITS(tptr)));
+                tptr+=2;
+                if (!TTEST2(*tptr, NODE_ID_LEN))
+                   goto trunctlv;
+               printf("\n\t\t\t  IS Neighbor: %s", isis_print_nodeid(tptr));
+                tptr+=(NODE_ID_LEN);
+                if (!TTEST2(*tptr, 3))
+                    goto trunctlv;
+                printf(", Metric: %d",EXTRACT_24BITS(tptr));
+                tptr+=3;
+                if (!TTEST2(*tptr, 1))
+                    goto trunctlv;
+                tslen=*(tptr++);
+                printf(", %ssub-TLVs present",tslen ? "" : "no ");
+                if (tslen) {
+                    printf(" (%u)",tslen);
+                    while (tslen>0) {
+                        if (!TTEST2(*tptr,2))
+                            goto trunctlv;
+                       subt=*(tptr++);
+                       subl=*(tptr++);
+                       if(!isis_print_is_reach_subtlv(tptr,subt,subl,"\n\t\t\t  "))
+                           return(0);
+                       tptr+=subl;
+                       tslen-=(subl+2);
+                        tmp-=(subl+2);
+                    }
+                }
+                tmp-=(SYSTEM_ID_LEN+7);
+            }
+            break;
+
+        case TLV_EXT_IS_REACH:
+            while (tmp>0) {
+                if (!TTEST2(*tptr, NODE_ID_LEN))
+                    goto trunctlv;
+               printf("\n\t\t\tIS Neighbor: %s", isis_print_nodeid(tptr));
+                tptr+=(NODE_ID_LEN);
+
+                if (!TTEST2(*tptr, 3))
+                    goto trunctlv;
+                printf(", Metric: %d",EXTRACT_24BITS(tptr));
+                tptr+=3;
+
+                if (!TTEST2(*tptr, 1))
+                    goto trunctlv;
+                tslen=*(tptr++); /* read out subTLV length */
+                printf(", %ssub-TLVs present",tslen ? "" : "no ");
+                if (tslen) {
+                    printf(" (%u)",tslen);
+                    while (tslen>0) {
+                        if (!TTEST2(*tptr,2))
+                            goto trunctlv;
+                       subt=*(tptr++);
+                       subl=*(tptr++);
+                       if(!isis_print_is_reach_subtlv(tptr,subt,subl,"\n\t\t\t  "))
+                           return(0);
+                       tptr+=subl;
+                       tslen-=(subl+2);
+                        tmp-=(subl+2);
+                    }
+                }
+                tmp-=(SYSTEM_ID_LEN+5);
+            }
+            break;
+        case TLV_IS_REACH:
+           if (!TTEST2(*tptr,1))  /* check if there is one byte left to read out the virtual flag */
+                goto trunctlv;
+            printf("\n\t\t\t%s",
+                   tok2str(isis_is_reach_virtual_values,
+                           "bogus virtual flag 0x%02x",
+                           *tptr++));
+           tlv_is_reach = (const struct isis_tlv_is_reach *)tptr;
+            while (tmp >= sizeof(struct isis_tlv_is_reach)) {
+               if (!TTEST(*tlv_is_reach))
+                   goto trunctlv;
+               printf("\n\t\t\tIS Neighbor: %s", isis_print_nodeid(tlv_is_reach->neighbor_nodeid));
+                isis_print_metric_block(&tlv_is_reach->isis_metric_block);
+               tmp -= sizeof(struct isis_tlv_is_reach);
+               tlv_is_reach++;
+           }
+            break;
+
+        case TLV_ESNEIGH:
+           tlv_es_reach = (const struct isis_tlv_es_reach *)tptr;
+            while (tmp >= sizeof(struct isis_tlv_es_reach)) {
+               if (!TTEST(*tlv_es_reach))
+                   goto trunctlv;
+               printf("\n\t\t\tES Neighbor: %s",
+                       isis_print_sysid(tlv_es_reach->neighbor_sysid,SYSTEM_ID_LEN));
+                isis_print_metric_block(&tlv_es_reach->isis_metric_block);
+               tmp -= sizeof(struct isis_tlv_es_reach);
+               tlv_es_reach++;
+           }
+            break;
 
-       if ((cksum[0] = off[0]) == 0 && (cksum[1] = off[1]) == 0)
-               return 0;
+            /* those two TLVs share the same format */
+       case TLV_IP_REACH:
+       case TLV_IP_REACH_EXT:
+           if (!isis_print_tlv_ip_reach(pptr, len))
+               return (1);
+           break;
+
+        case TLV_MT_IP_REACH:
+           while (tmp>0) {
+                if (!TTEST2(*tptr, 2))
+                   goto trunctlv;
+
+                printf("\n\t\t\t%s",
+                       tok2str(isis_mt_values,
+                               "Reserved for IETF Consensus",
+                               ISIS_MASK_MTID(EXTRACT_16BITS(tptr))));
+
+               printf(" Topology (0x%03x)",
+                       ISIS_MASK_MTID(EXTRACT_16BITS(tptr)));
+                tptr+=2;
+
+               memset (prefix, 0, 4);
+               if (!TTEST2(*tptr, 4))
+                   return (1);
+               metric = EXTRACT_32BITS(tptr);
+               tptr+=4;
+
+               if (!TTEST2(*tptr, 1)) /* fetch status byte */
+                   return (1);
+               j=*(tptr);
+               bit_length = (*(tptr)++&0x3f);
+               byte_length = (bit_length + 7) / 8; /* prefix has variable length encoding */
+
+               if (!TTEST2(*tptr, byte_length))
+                   return (1);
+               memcpy(prefix,tptr,byte_length);
+                tptr+=byte_length;
+               printf("\n\t\t\tIPv4 prefix: %s/%d",
+                      ipaddr_string(prefix),
+                      bit_length);
+
+               printf("\n\t\t\t  Metric: %u, Distribution: %s",
+                      metric,
+                      ISIS_MASK_TLV_EXT_IP_UPDOWN(j) ? "down" : "up");
+
+               printf(", %ssub-TLVs present",
+                      ISIS_MASK_TLV_EXT_IP_SUBTLV(j) ? "" : "no ");
+
+               if (ISIS_MASK_TLV_EXT_IP_SUBTLV(j)) {
+                    /* assume that one prefix can hold more
+                       than one subTLV - therefore the first byte must reflect
+                       the aggregate bytecount of the subTLVs for this prefix
+                     */
+                   if (!TTEST2(*tptr, 1))
+                     return (1);
+                    tslen=*(tptr++);
+                    tmp--;
+                   printf(" (%u)",tslen);   /* print out subTLV length */
+
+                    while (tslen>0) {
+                        if (!TTEST2(*tptr,2))
+                            goto trunctlv;
+                       subt=*(tptr++);
+                       subl=*(tptr++);
+                       if(!isis_print_ip_reach_subtlv(tptr,subt,subl,"\n\t\t\t  "))
+                           return(0);
+                       tptr+=subl;
+                       tslen-=(subl+2);
+                        tmp-=(subl+2);
+                    }
+               }
+               tmp-=(7+byte_length);
+           }
+           break;
+
+       case TLV_EXT_IP_REACH:
+           while (tmp>0) {
+               memset (prefix, 0, 4);
+               if (!TTEST2(*tptr, 4))
+                   return (1);
+               metric = EXTRACT_32BITS(tptr);
+               tptr+=4;
+
+               if (!TTEST2(*tptr, 1)) /* fetch status byte */
+                   return (1);
+               j=*(tptr);
+               bit_length = (*(tptr)++&0x3f);
+               byte_length = (bit_length + 7) / 8; /* prefix has variable length encoding */
+
+               if (!TTEST2(*tptr, byte_length))
+                   return (1);
+               memcpy(prefix,tptr,byte_length);
+                tptr+=byte_length;
+               printf("\n\t\t\tIPv4 prefix: %s/%d",
+                      ipaddr_string(prefix),
+                      bit_length);
+
+               printf("\n\t\t\t  Metric: %u, Distribution: %s",
+                      metric,
+                      ISIS_MASK_TLV_EXT_IP_UPDOWN(j) ? "down" : "up");
+
+               printf(", %ssub-TLVs present",
+                      ISIS_MASK_TLV_EXT_IP_SUBTLV(j) ? "" : "no ");
+
+               if (ISIS_MASK_TLV_EXT_IP_SUBTLV(j)) {
+                    /* assume that one prefix can hold more
+                       than one subTLV - therefore the first byte must reflect
+                       the aggregate bytecount of the subTLVs for this prefix
+                     */
+                   if (!TTEST2(*tptr, 1))
+                     return (1);
+                    tslen=*(tptr++);
+                    tmp--;
+                   printf(" (%u)",tslen);   /* print out subTLV length */
+
+                    while (tslen>0) {
+                        if (!TTEST2(*tptr,2))
+                            goto trunctlv;
+                       subt=*(tptr++);
+                       subl=*(tptr++);
+                       if(!isis_print_ip_reach_subtlv(tptr,subt,subl,"\n\t\t\t  "))
+                           return(0);
+                       tptr+=subl;
+                       tslen-=(subl+2);
+                        tmp-=(subl+2);
+                    }
+               }
+               tmp-=(5+byte_length);
+           }
+           break;
+
+#ifdef INET6
+
+       case TLV_IP6_REACH:
+           while (tmp>0) {
+               if (!TTEST2(*tptr, 4))
+                   return (1);
+               metric = EXTRACT_32BITS(tptr);
+               tptr+=4;
+
+               if (!TTEST2(*tptr, 2))
+                   return (1);
+               j=*(tptr++);
+               bit_length = (*(tptr)++);
+               byte_length = (bit_length + 7) / 8;
+               if (!TTEST2(*tptr, byte_length))
+                   return (1);
+
+               memset(prefix6, 0, 16);
+               memcpy(prefix6,tptr,byte_length);
+                tptr+=byte_length;
+               printf("\n\t\t\tIPv6 prefix: %s/%u",
+                      ip6addr_string(prefix6),
+                      bit_length);
+
+               printf("\n\t\t\t  Metric: %u, %s, Distribution: %s, %ssub-TLVs present",
+                   metric,
+                   ISIS_MASK_TLV_IP6_IE(j) ? "External" : "Internal",
+                   ISIS_MASK_TLV_IP6_UPDOWN(j) ? "down" : "up",
+                   ISIS_MASK_TLV_IP6_SUBTLV(j) ? "" : "no ");
+
+               if (ISIS_MASK_TLV_IP6_SUBTLV(j)) {
+                    /* assume that one prefix can hold more
+                       than one subTLV - therefore the first byte must reflect
+                       the aggregate bytecount of the subTLVs for this prefix
+                     */
+                   if (!TTEST2(*tptr, 1))
+                     return (1);
+                    tslen=*(tptr++);
+                    tmp--;
+                   printf(" (%u)",tslen);   /* print out subTLV length */
+
+                    while (tslen>0) {
+                        if (!TTEST2(*tptr,2))
+                            goto trunctlv;
+                       subt=*(tptr++);
+                       subl=*(tptr++);
+                       if(!isis_print_ip_reach_subtlv(tptr,subt,subl,"\n\t\t\t  "))
+                           return(0);
+                       tptr+=subl;
+                       tslen-=(subl+2);
+                        tmp-=(subl+2);
+                    }
+               }
+               tmp-=(6+byte_length);
+           }
+
+           break;
+#endif
+
+#ifdef INET6
+       case TLV_IP6ADDR:
+           while (tmp>0) {
+               if (!TTEST2(*tptr, 16))
+                   goto trunctlv;
+
+                printf("\n\t\t\tIPv6 interface address: %s",
+                      ip6addr_string(tptr));
+
+               tptr += 16;
+               tmp -= 16;
+           }
+           break;
+#endif
+       case TLV_AUTH:
+           if (!TTEST2(*tptr, 1))
+               goto trunctlv;
+
+            printf("\n\t\t\t%s: ",
+                   tok2str(isis_subtlv_auth_values,
+                           "unknown Authentication type 0x%02x",
+                           *tptr));
+
+           switch (*tptr) {
+           case SUBTLV_AUTH_SIMPLE:
+               for(i=1;i<len;i++) {
+                   if (!TTEST2(*(tptr+i), 1))
+                       goto trunctlv;
+                   printf("%c",*(tptr+i));
+               }
+               break;
+           case SUBTLV_AUTH_MD5:
+               for(i=1;i<len;i++) {
+                   if (!TTEST2(*(tptr+i), 1))
+                       goto trunctlv;
+                   printf("%02x",*(tptr+i));
+               }
+               if (len != SUBTLV_AUTH_MD5_LEN+1)
+                 printf(", (malformed subTLV) ");
+               break;
+           case SUBTLV_AUTH_PRIVATE:
+           default:
+               if(!isis_print_unknown_data(tptr+1,"\n\t\t\t    ",len-1))
+                   return(0);
+               break;
+           }
+           break;
+
+       case TLV_PTP_ADJ:
+           tlv_ptp_adj = (const struct isis_tlv_ptp_adj *)tptr;
+           if(tmp>=1) {
+               if (!TTEST2(*tptr, 1))
+                   goto trunctlv;
+               printf("\n\t\t\tAdjacency State: %s",
+                      tok2str(isis_ptp_adjancey_values, "0x%02x", *tptr));
+               tmp--;
+           }
+           if(tmp>sizeof(tlv_ptp_adj->extd_local_circuit_id)) {
+               if (!TTEST2(tlv_ptp_adj->extd_local_circuit_id,
+                            sizeof(tlv_ptp_adj->extd_local_circuit_id)))
+                   goto trunctlv;
+               printf("\n\t\t\tExtended Local circuit ID: 0x%08x",
+                      EXTRACT_32BITS(tlv_ptp_adj->extd_local_circuit_id));
+               tmp-=sizeof(tlv_ptp_adj->extd_local_circuit_id);
+           }
+           if(tmp>=SYSTEM_ID_LEN) {
+               if (!TTEST2(tlv_ptp_adj->neighbor_sysid, SYSTEM_ID_LEN))
+                   goto trunctlv;
+               printf("\n\t\t\tNeighbor SystemID: %s",
+                      isis_print_sysid(tlv_ptp_adj->neighbor_sysid,SYSTEM_ID_LEN));
+               tmp-=SYSTEM_ID_LEN;
+           }
+           if(tmp>=sizeof(tlv_ptp_adj->neighbor_extd_local_circuit_id)) {
+               if (!TTEST2(tlv_ptp_adj->neighbor_extd_local_circuit_id,
+                            sizeof(tlv_ptp_adj->neighbor_extd_local_circuit_id)))
+                   goto trunctlv;
+               printf("\n\t\t\tNeighbor Extended Local circuit ID: 0x%08x",
+                      EXTRACT_32BITS(tlv_ptp_adj->neighbor_extd_local_circuit_id));
+           }
+           break;
+
+       case TLV_PROTOCOLS:
+           printf("\n\t\t\tNLPID(s): ");
+           while (tmp>0) {
+               if (!TTEST2(*(tptr), 1))
+                   goto trunctlv;
+               printf("%s",
+                       tok2str(isis_nlpid_values,
+                               "Unknown 0x%02x",
+                               *tptr++));
+               if (tmp>1) /* further NPLIDs ? - put comma */
+                   printf(", ");
+                tmp--;
+           }
+           break;
+
+       case TLV_TE_ROUTER_ID:
+           if (!TTEST2(*pptr, 4))
+               goto trunctlv;
+           printf("\n\t\t\tTraffic Engineering Router ID: %s", ipaddr_string(pptr));
+           break;
+
+       case TLV_IPADDR:
+           while (tmp>0) {
+               if (!TTEST2(*tptr, 4))
+                   goto trunctlv;
+               printf("\n\t\t\tIPv4 interface address: %s", ipaddr_string(tptr));
+               tptr += 4;
+               tmp -= 4;
+           }
+           break;
+
+       case TLV_HOSTNAME:
+           printf("\n\t\t\tHostname: ");
+           while (tmp>0) {
+               if (!TTEST2(*tptr, 1))
+                   goto trunctlv;
+               printf("%c",*tptr++);
+                tmp--;
+           }
+           break;
+
+       case TLV_SHARED_RISK_GROUP:
+           if (!TTEST2(*tptr, NODE_ID_LEN))
+             goto trunctlv;
+           printf("\n\t\t\tIS Neighbor: %s", isis_print_nodeid(tptr));
+           tptr+=(NODE_ID_LEN);
+           len-=(NODE_ID_LEN);
+
+           if (!TTEST2(*tptr, 1))
+             goto trunctlv;
+           printf(", %s", ISIS_MASK_TLV_SHARED_RISK_GROUP(*tptr++) ? "numbered" : "unnumbered");
+           len--;
+
+           if (!TTEST2(*tptr,4))
+             goto trunctlv;
+           printf("\n\t\t\tIPv4 interface address: %s", ipaddr_string(tptr));
+           tptr+=4;
+           len-=4;
+
+           if (!TTEST2(*tptr,4))
+             goto trunctlv;
+           printf("\n\t\t\tIPv4 neighbor address: %s", ipaddr_string(tptr));
+           tptr+=4;
+           len-=4;
+
+           while (tmp>0) {
+             if (!TTEST2(*tptr, 4))
+               goto trunctlv;
+             printf("\n\t\t\tLink-ID: 0x%08x", EXTRACT_32BITS(tptr));
+             tptr+=4;
+             len-=4;
+           }
+           break;
+
+       case TLV_LSP:
+           tlv_lsp = (const struct isis_tlv_lsp *)tptr;
+           while(tmp>0) {
+               printf("\n\t\t\tlsp-id: %s",
+                       isis_print_nodeid(tlv_lsp->lsp_id));
+               if (!TTEST((tlv_lsp->lsp_id)[NODE_ID_LEN]))
+                   goto trunctlv;
+               printf("-%02x",(tlv_lsp->lsp_id)[NODE_ID_LEN]);
+               if (!TTEST2(tlv_lsp->sequence_number, 4))
+                   goto trunctlv;
+               printf(", seq: 0x%08x",EXTRACT_32BITS(tlv_lsp->sequence_number));
+               if (!TTEST2(tlv_lsp->remaining_lifetime, 2))
+                   goto trunctlv;
+               printf(", lifetime: %5ds",EXTRACT_16BITS(tlv_lsp->remaining_lifetime));
+               if (!TTEST2(tlv_lsp->checksum, 2))
+                   goto trunctlv;
+               printf(", chksum: 0x%04x",EXTRACT_16BITS(tlv_lsp->checksum));
+               tmp-=sizeof(struct isis_tlv_lsp);
+               tlv_lsp++;
+           }
+           break;
+
+       case TLV_CHECKSUM:
+           if (!TTEST2(*tptr, 2))
+               goto trunctlv;
+           printf("\n\t\t\tchecksum: 0x%04x (%s)",
+                  EXTRACT_16BITS(tptr),
+                   (osi_cksum(optr, length)) ? "incorrect" : "correct");
+           break;
+
+       case TLV_MT_SUPPORTED:
+           while (tmp>1) {
+               /* length can only be a multiple of 2, otherwise there is
+                  something broken -> so decode down until length is 1 */
+               if (tmp!=1) {
+                   if (!TTEST2(*tptr, 2))
+                       goto trunctlv;
+                    printf("\n\t\t\t%s",
+                           tok2str(isis_mt_values,
+                                   "Reserved for IETF Consensus",
+                                   ISIS_MASK_MTID(EXTRACT_16BITS(tptr))));
+
+                   printf(" Topology (0x%03x)%s%s",
+                          ISIS_MASK_MTID(EXTRACT_16BITS(tptr)),
+                          ISIS_MASK_MTSUB(EXTRACT_16BITS(tptr)) ? "" : ", no sub-TLVs present",
+                          ISIS_MASK_MTATT(EXTRACT_16BITS(tptr)) ? ", ATT bit set" : "" );
+               } else {
+                   printf("\n\t\t\tmalformed MT-ID");
+                   break;
+               }
+               tmp-=2;
+               tptr+=2;
+           }
+           break;
+
+       case TLV_RESTART_SIGNALING:
+            if (!TTEST2(*tptr, 3))
+                goto trunctlv;
+           rr = ISIS_MASK_TLV_RESTART_RR(*tptr);
+           ra = ISIS_MASK_TLV_RESTART_RA(*tptr);
+           tptr++;
+           time_remain = EXTRACT_16BITS(tptr);
+           printf("\n\t\t\tRestart Request bit %s, Restart Acknowledgement bit %s\n\t\t\tRemaining holding time: %us",
+                  rr ? "set" : "clear", ra ? "set" : "clear", time_remain);
+           break;
+
+        case TLV_IDRP_INFO:
+            if (!TTEST2(*tptr, 1))
+                goto trunctlv;
+            printf("\n\t\t\tInter-Domain Information Type: %s",
+                   tok2str(isis_subtlv_idrp_values,
+                           "Unknown (0x%02x)",
+                           *tptr));
+            switch (*tptr++) {
+            case SUBTLV_IDRP_ASN:
+                if (!TTEST2(*tptr, 2)) /* fetch AS number */
+                    goto trunctlv;
+                printf("AS Number: %u",EXTRACT_16BITS(tptr));
+                break;
+            case SUBTLV_IDRP_LOCAL:
+            case SUBTLV_IDRP_RES:
+            default:
+                if(!isis_print_unknown_data(tptr,"\n\t\t\t",len-1))
+                    return(0);
+                break;
+            }
+            break;
+
+        case TLV_LSP_BUFFERSIZE:
+            if (!TTEST2(*tptr, 2))
+                goto trunctlv;
+                printf("LSP Buffersize: %u",EXTRACT_16BITS(tptr));
+            break;
+
+        case TLV_PART_DIS:
+            while (tmp >= SYSTEM_ID_LEN) {
+            if (!TTEST2(*tptr, SYSTEM_ID_LEN))
+                goto trunctlv;
+            printf("%s",isis_print_sysid(tptr,SYSTEM_ID_LEN));
+            tptr+=SYSTEM_ID_LEN;
+            tmp-=SYSTEM_ID_LEN;
+            }
+            break;
+
+        case TLV_PREFIX_NEIGH:
+            if (!TTEST2(*tptr, sizeof(struct isis_metric_block)))
+                goto trunctlv;
+            printf("Metric Block");
+            isis_print_metric_block((const struct isis_metric_block *)tptr);
+            tptr+=sizeof(struct isis_metric_block);
+            tmp-=sizeof(struct isis_metric_block);
+
+            while(tmp>0) {
+                if (!TTEST2(*tptr, 1))
+                    goto trunctlv;
+                prefix_len=*tptr++; /* read out prefix length in semioctets*/
+                tmp--;
+                if (!TTEST2(*tptr, prefix_len/2))
+                    goto trunctlv;
+                printf("\n\t\t\tAddress: %s/%u",
+                       print_nsap(tptr,prefix_len/2),
+                       prefix_len*4);
+                tptr+=prefix_len/2;
+                tmp-=prefix_len/2;
+            }
+            break;
+
+            /*
+             * FIXME those are the defined TLVs that lack a decoder
+             * you are welcome to contribute code ;-)
+             */
+
+        case TLV_IS_ALIAS_ID:
+        case TLV_DECNET_PHASE4:
+        case TLV_LUCENT_PRIVATE:
+        case TLV_IPAUTH:
+        case TLV_NORTEL_PRIVATE1:
+        case TLV_NORTEL_PRIVATE2:
+        case TLV_MT_IP6_REACH:
+
+       default:
+           if(!isis_print_unknown_data(pptr,"\n\t\t\t",len))
+               return(0);
+           break;
+       }
+
+       pptr += len;
+       packet_len -= len;
+    }
+
+    if (packet_len != 0) {
+       printf("\n\t\t\t %d straggler bytes", packet_len);
+    }
+    return (1);
+
+trunc:
+    fputs("[|isis]", stdout);
+    return (1);
+
+trunctlv:
+    printf("\n\t\t\t packet exceeded snapshot");
+    return(1);
+}
+
+/*
+ * Verify the checksum.  See 8473-1, Appendix C, section C.4.
+ */
+
+static int
+osi_cksum(const u_char *tptr, u_int len)
+{
+       int32_t c0 = 0, c1 = 0;
 
-       off[0] = off[1] = 0;
        while ((int)--len >= 0) {
-               c0 += *p++;
-               c1 += c0;
+               c0 += *tptr++;
                c0 %= 255;
+               c1 += c0;
                c1 %= 255;
        }
-       x = (c0 * f - c1);
-       if (x < 0)
-               x = 255 - (-x % 255);
-       else
-               x %= 255;
-       y = -1 * (x + c0);
-       if (y < 0)
-               y = 255 - (-y % 255);
-       else
-               y %= 255;
-
-       off[0] = x;
-       off[1] = y;
-
-       return (off[0] != cksum[0] || off[1] != cksum[1]);
+       return (c0 | c1);
 }