* VLAN TRUNKING PROTOCOL (VTP)
*
* Reference documentation:
- * http://www.cisco.com/en/US/tech/tk389/tk689/technologies_tech_note09186a0080094c52.shtml
- * http://www.cisco.com/warp/public/473/21.html
+ * http://www.cisco.com/en/US/tech/tk389/tk689/technologies_tech_note09186a0080094c52.shtml
+ * http://www.cisco.com/warp/public/473/21.html
+ * http://www.cisco.com/univercd/cc/td/doc/product/lan/trsrb/frames.htm
*
*/
+#define NETDISSECT_REWORKED
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <tcpdump-stdinc.h>
-#include <stdio.h>
-#include <string.h>
-
#include "interface.h"
#include "addrtoname.h"
-#include "extract.h"
-#include "nlpid.h"
+#include "extract.h"
#define VTP_HEADER_LEN 36
#define VTP_DOMAIN_NAME_LEN 32
#define VTP_JOIN_MESSAGE 0x04
struct vtp_vlan_ {
- u_int8_t len;
- u_int8_t status;
- u_int8_t type;
- u_int8_t name_len;
- u_int16_t vlanid;
- u_int16_t mtu;
- u_int32_t index;
+ uint8_t len;
+ uint8_t status;
+ uint8_t type;
+ uint8_t name_len;
+ uint16_t vlanid;
+ uint16_t mtu;
+ uint32_t index;
};
-static struct tok vtp_message_type_values[] = {
+static const struct tok vtp_message_type_values[] = {
{ VTP_SUMMARY_ADV, "Summary advertisement"},
{ VTP_SUBSET_ADV, "Subset advertisement"},
{ VTP_ADV_REQUEST, "Advertisement request"},
{ 0, NULL }
};
-static struct tok vtp_header_values[] = {
+static const struct tok vtp_header_values[] = {
{ 0x01, "Followers"}, /* On Summary advertisement, 3rd byte is Followers */
{ 0x02, "Seq number"}, /* On Subset advertisement, 3rd byte is Sequence number */
{ 0x03, "Rsvd"}, /* On Adver. requests 3rd byte is Rsvd */
{ 0, NULL }
};
-static struct tok vtp_stp_type_values[] = {
- { 1, "SRT"},
- { 2, "SRB"},
- { 3, "Auto"},
- { 0, NULL }
-};
-
-static struct tok vtp_vlan_type_values[] = {
+static const struct tok vtp_vlan_type_values[] = {
{ 0x01, "Ethernet"},
{ 0x02, "FDDI"},
{ 0x03, "TrCRF"},
{ 0, NULL }
};
-static struct tok vtp_vlan_status[] = {
+static const struct tok vtp_vlan_status[] = {
{ 0x00, "Operational"},
{ 0x01, "Suspended"},
{ 0, NULL }
};
+#define VTP_VLAN_SOURCE_ROUTING_RING_NUMBER 0x01
+#define VTP_VLAN_SOURCE_ROUTING_BRIDGE_NUMBER 0x02
+#define VTP_VLAN_STP_TYPE 0x03
+#define VTP_VLAN_PARENT_VLAN 0x04
+#define VTP_VLAN_TRANS_BRIDGED_VLAN 0x05
+#define VTP_VLAN_PRUNING 0x06
+#define VTP_VLAN_BRIDGE_TYPE 0x07
+#define VTP_VLAN_ARP_HOP_COUNT 0x08
+#define VTP_VLAN_STE_HOP_COUNT 0x09
+#define VTP_VLAN_BACKUP_CRF_MODE 0x0A
+
+static const struct tok vtp_vlan_tlv_values[] = {
+ { VTP_VLAN_SOURCE_ROUTING_RING_NUMBER, "Source-Routing Ring Number TLV"},
+ { VTP_VLAN_SOURCE_ROUTING_BRIDGE_NUMBER, "Source-Routing Bridge Number TLV"},
+ { VTP_VLAN_STP_TYPE, "STP type TLV"},
+ { VTP_VLAN_PARENT_VLAN, "Parent VLAN TLV"},
+ { VTP_VLAN_TRANS_BRIDGED_VLAN, "Translationally bridged VLANs TLV"},
+ { VTP_VLAN_PRUNING, "Pruning TLV"},
+ { VTP_VLAN_BRIDGE_TYPE, "Bridge Type TLV"},
+ { VTP_VLAN_ARP_HOP_COUNT, "Max ARP Hop Count TLV"},
+ { VTP_VLAN_STE_HOP_COUNT, "Max STE Hop Count TLV"},
+ { VTP_VLAN_BACKUP_CRF_MODE, "Backup CRF Mode TLV"},
+ { 0, NULL }
+};
+
+static const struct tok vtp_stp_type_values[] = {
+ { 1, "SRT"},
+ { 2, "SRB"},
+ { 3, "Auto"},
+ { 0, NULL }
+};
+
void
-vtp_print (const u_char *pptr, u_int length)
+vtp_print (netdissect_options *ndo,
+ const u_char *pptr, u_int length)
{
- int type, len, tlv_len;
+ int type, len, tlv_len, tlv_value;
const u_char *tptr;
const struct vtp_vlan_ *vtp_vlan;
if (length < VTP_HEADER_LEN)
goto trunc;
- tptr = pptr;
+ tptr = pptr;
- if (!TTEST2(*tptr, VTP_HEADER_LEN))
- goto trunc;
+ ND_TCHECK2(*tptr, VTP_HEADER_LEN);
type = *(tptr+1);
- printf("VTPv%u, Message %s (0x%02x), length %u",
- *tptr,
+ ND_PRINT((ndo, "VTPv%u, Message %s (0x%02x), length %u",
+ *tptr,
tok2str(vtp_message_type_values,"Unknown message type", type),
*(tptr+1),
- length);
+ length));
/* In non-verbose mode, just print version and message type */
- if (vflag < 1) {
+ if (ndo->ndo_vflag < 1) {
return;
}
/* verbose mode print all fields */
- printf("\n\tDomain name: %s, Flags [%s] %u",
+ ND_PRINT((ndo, "\n\tDomain name: %s, %s: %u",
(tptr+4),
tok2str(vtp_header_values,"Unknown",*(tptr+1)),
- *(tptr+2));
+ *(tptr+2)));
tptr += VTP_HEADER_LEN;
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | MD5 digest (16 bytes) |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- *
+ *
*/
- printf("\n\t Config Rev %x, Updater %s",
+ ND_PRINT((ndo, "\n\t Config Rev %x, Updater %s",
EXTRACT_32BITS(tptr),
- ipaddr_string(tptr+4));
- tptr += 8;
- printf(", Timestamp 0x%08x 0x%08x 0x%08x",
+ ipaddr_string(ndo, tptr+4)));
+ tptr += 8;
+ ND_PRINT((ndo, ", Timestamp 0x%08x 0x%08x 0x%08x",
EXTRACT_32BITS(tptr),
EXTRACT_32BITS(tptr + 4),
- EXTRACT_32BITS(tptr + 8));
+ EXTRACT_32BITS(tptr + 8)));
tptr += VTP_UPDATE_TIMESTAMP_LEN;
- printf(", MD5 digest: %08x%08x%08x%08x",
+ ND_PRINT((ndo, ", MD5 digest: %08x%08x%08x%08x",
EXTRACT_32BITS(tptr),
EXTRACT_32BITS(tptr + 4),
EXTRACT_32BITS(tptr + 8),
- EXTRACT_32BITS(tptr + 12));
+ EXTRACT_32BITS(tptr + 12)));
tptr += VTP_MD5_DIGEST_LEN;
break;
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | VLAN info field N |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- *
+ *
*/
- printf(", Config Rev %x", EXTRACT_32BITS(tptr));
+ ND_PRINT((ndo, ", Config Rev %x", EXTRACT_32BITS(tptr)));
- /*
+ /*
* VLAN INFORMATION
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
if (len == 0)
break;
- if (!TTEST2(*tptr, len))
- goto trunc;
+ ND_TCHECK2(*tptr, len);
vtp_vlan = (struct vtp_vlan_*)tptr;
- printf("\n\tVLAN info status %s, type %s, VLAN-id %u, MTU %u, SAID 0x%08x, Name %s",
+ ND_PRINT((ndo, "\n\tVLAN info status %s, type %s, VLAN-id %u, MTU %u, SAID 0x%08x, Name %s",
tok2str(vtp_vlan_status,"Unknown",vtp_vlan->status),
tok2str(vtp_vlan_type_values,"Unknown",vtp_vlan->type),
EXTRACT_16BITS(&vtp_vlan->vlanid),
EXTRACT_16BITS(&vtp_vlan->mtu),
EXTRACT_32BITS(&vtp_vlan->index),
- (tptr + VTP_VLAN_INFO_OFFSET));
- tptr += len;
-
- /* FIXME: TLV dissector missing */
-
- /* The following URL:
- http://www.cisco.com/univercd/cc/td/doc/product/lan/trsrb/frames.htm
- talks about type (2 bytes) and length (2 bytes), that is not true...
- */
+ (tptr + VTP_VLAN_INFO_OFFSET)));
+
+ /*
+ * Vlan names are aligned to 32-bit boundaries.
+ */
+ len -= VTP_VLAN_INFO_OFFSET + 4*((vtp_vlan->name_len + 3)/4);
+ tptr += VTP_VLAN_INFO_OFFSET + 4*((vtp_vlan->name_len + 3)/4);
+
+ /* TLV information follows */
+
+ while (len > 0) {
+
+ /*
+ * Cisco specs says 2 bytes for type + 2 bytes for length, take only 1
+ * See: http://www.cisco.com/univercd/cc/td/doc/product/lan/trsrb/frames.htm
+ */
+ type = *tptr;
+ tlv_len = *(tptr+1);
+
+ ND_PRINT((ndo, "\n\t\t%s (0x%04x) TLV",
+ tok2str(vtp_vlan_tlv_values, "Unknown", type),
+ type));
+
+ /*
+ * infinite loop check
+ */
+ if (type == 0 || tlv_len == 0) {
+ return;
+ }
+
+ ND_TCHECK2(*tptr, tlv_len * 2 +2);
+
+ tlv_value = EXTRACT_16BITS(tptr+2);
+
+ switch (type) {
+ case VTP_VLAN_STE_HOP_COUNT:
+ ND_PRINT((ndo, ", %u", tlv_value));
+ break;
+
+ case VTP_VLAN_PRUNING:
+ ND_PRINT((ndo, ", %s (%u)",
+ tlv_value == 1 ? "Enabled" : "Disabled",
+ tlv_value));
+ break;
+
+ case VTP_VLAN_STP_TYPE:
+ ND_PRINT((ndo, ", %s (%u)",
+ tok2str(vtp_stp_type_values, "Unknown", tlv_value),
+ tlv_value));
+ break;
+
+ case VTP_VLAN_BRIDGE_TYPE:
+ ND_PRINT((ndo, ", %s (%u)",
+ tlv_value == 1 ? "SRB" : "SRT",
+ tlv_value));
+ break;
+
+ case VTP_VLAN_BACKUP_CRF_MODE:
+ ND_PRINT((ndo, ", %s (%u)",
+ tlv_value == 1 ? "Backup" : "Not backup",
+ tlv_value));
+ break;
+
+ /*
+ * FIXME those are the defined TLVs that lack a decoder
+ * you are welcome to contribute code ;-)
+ */
+
+ case VTP_VLAN_SOURCE_ROUTING_RING_NUMBER:
+ case VTP_VLAN_SOURCE_ROUTING_BRIDGE_NUMBER:
+ case VTP_VLAN_PARENT_VLAN:
+ case VTP_VLAN_TRANS_BRIDGED_VLAN:
+ case VTP_VLAN_ARP_HOP_COUNT:
+ default:
+ print_unknown_data(ndo, tptr, "\n\t\t ", 2 + tlv_len*2);
+ break;
+ }
+ len -= 2 + tlv_len*2;
+ tptr += 2 + tlv_len*2;
+ }
}
break;
*
*/
- printf("\n\tStart value: %u", EXTRACT_32BITS(tptr));
+ ND_PRINT((ndo, "\n\tStart value: %u", EXTRACT_32BITS(tptr)));
break;
case VTP_JOIN_MESSAGE:
return;
trunc:
- printf("[|vtp]");
+ ND_PRINT((ndo, "[|vtp]"));
}
/*
projects / tcpdump / blobdiff