There's another Cisco-private encapsulation of BPDUs.

At least according to the Wireshark STP dissector, SNAP frames with the
Cisco OUI and a PID of 0x010c contain BPDUs, for "VLAN Bridge".

diff --git a/llc.h b/llc.h
index faa72561c9a972ce9be2e42c3389132db5eb7bd8..660466994f5559ae46011324ac57546e56764e2c 100644 (file)
--- a/llc.h
+++ b/llc.h
@@ -106,6 +106,7 @@
 #define        PID_CISCO_DTP           0x2004  /* Cisco Dynamic Trunk Protocol */
 #define        PID_CISCO_UDLD          0x0111  /* Unidirectional Link Detection */
 #define        PID_CISCO_PVST          0x010b  /* Per VLAN Spanning Tree+ and RPVST+ */
+#define        PID_CISCO_VLANBRIDGE    0x010c  /* "VLAN Bridge", according to Wireshark */
 
 /*
  * PIDs for use with OUI_RFC2684.

diff --git a/print-llc.c b/print-llc.c
index a1934715c18843abaf98d4884b5cfe5e7d0f5af5..5ba81894c4a02ac6b41c1a13d058d36f73b60342 100644 (file)
--- a/print-llc.c
+++ b/print-llc.c
@@ -107,6 +107,7 @@ static const struct tok cisco_values[] = {
        { PID_CISCO_DTP, "DTP" },
        { PID_CISCO_UDLD, "UDLD" },
        { PID_CISCO_PVST, "PVST" },
+       { PID_CISCO_VLANBRIDGE, "VLAN Bridge" },
        { 0,             NULL }
 };
 
@@ -453,6 +454,7 @@ snap_print(const u_char *p, u_int length, u_int caplen, u_int bridge_pad)
                         vtp_print(p, length);
                         return (1);
                 case PID_CISCO_PVST:
+                case PID_CISCO_VLANBRIDGE:
                         stp_print(p, length);
                         return (1);
                 default: