Dump the values of the "flags" and "ttl" fields of the CDP header.

Don't treat the CDP header as an in-memory data structure; that might
cause problems if it's not aligned on a 2-byte boundary.

Make the type and length fields of a TLV unsigned.

Correctly check for the end of the (captured part of the) frame.

Show most TLVs as "expandable" entries, where they expand into type,
length, and data entries.

Dissect "unknown" TLVs.

svn path=/trunk/; revision=571

1 files changed, 119 insertions, 62 deletions

diff --git a/packet-cdp.c b/packet-cdp.c
index fa2448ad68..dda4cc95a6 100644
--- a/packet-cdp.c
+++ b/packet-cdp.c
@@ -2,7 +2,7 @@
  * Routines for the disassembly of the "Cisco Discovery Protocol"
  * (c) Copyright Hannes R. Boehm <hannes@boehm.org>
  *
- * $Id: packet-cdp.c,v 1.11 1999/08/24 22:36:34 gram Exp $
+ * $Id: packet-cdp.c,v 1.12 1999/08/25 00:24:32 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@zing.org>
@@ -50,19 +50,13 @@ add_multi_line_string_to_tree(proto_tree *tree, gint start, gint len,
 
 void 
 dissect_cdp(const u_char *pd, int offset, frame_data *fd, proto_tree *tree) {
+    proto_item *ti; 
     proto_tree *cdp_tree = NULL;
-	proto_item *ti; 
-    
-    typedef struct _e_cdp_hdr{
-		char version;
-		char flags;
-		gint16 ttl;
-	} e_cdp_hdr;
-
-    e_cdp_hdr *cdp_hdr;
+    guint16 type;
+    guint16 length;
     char *stringmem;
-    gint16 type;
-    gint16 length;
+    proto_item *tlvi;
+    proto_tree *tlv_tree;
 
     if (check_col(fd, COL_PROTOCOL))
         col_add_str(fd, COL_PROTOCOL, "CDP");
@@ -70,44 +64,92 @@ dissect_cdp(const u_char *pd, int offset, frame_data *fd, proto_tree *tree) {
         col_add_str(fd, COL_INFO, "Cisco Discovery Protocol"); 
 
     if(tree){
-        ti = proto_tree_add_item(tree, proto_cdp, offset, (fd->cap_len - offset), NULL);
+        ti = proto_tree_add_item(tree, proto_cdp, offset, END_OF_FRAME, NULL);
 	cdp_tree = proto_item_add_subtree(ti, ETT_CDP);
 	
 	/* CDP header */
-	cdp_hdr = (e_cdp_hdr *) &pd[offset];
-	proto_tree_add_text(cdp_tree, offset, 1, "Version: %d", cdp_hdr->version);
-	proto_tree_add_text(cdp_tree, offset+1, 1, "Flags (unknown)");
-	proto_tree_add_text(cdp_tree, offset+2, 2, "TTL (unknown)");
-	offset+=4;
+	proto_tree_add_text(cdp_tree, offset, 1, "Version: %u", pd[offset]);
+	offset += 1;
+	proto_tree_add_text(cdp_tree, offset, 1, "Flags: %x (unknown)",
+	    pd[offset]);
+	offset += 1;
+	proto_tree_add_text(cdp_tree, offset, 2, "TTL: %u (unknown)",
+	    pntohs(&pd[offset]));
+	offset += 2;
 
-	/* CVS -> exit here 
-    	dissect_data(pd, offset, fd, cdp_tree);
-		return;
-     */
-	
-	while( offset <= fd->cap_len ){
+	while( offset < pi.captured_len ){
 		type = pntohs(&pd[offset + TLV_TYPE]);
 		length = pntohs(&pd[offset + TLV_LENGTH]);
 		proto_tree_add_item_hidden(cdp_tree, hf_cdp_tlvtype, offset+TLV_TYPE, 2, type);
 		proto_tree_add_item_hidden(cdp_tree, hf_cdp_tlvlength, offset+TLV_LENGTH, 2, length);
 		switch( type ){
-			case 0: /* ??? Mgmt Addr */
+			case 0:
+				/* ??? Mgmt Addr; in this one, the "length"
+				   field doesn't include the length of the
+				   type and length fields. */
+				tlvi = proto_tree_add_text(cdp_tree, offset,
+				    length + 4, "Type: %u (Mgmt addr?), length: %u",
+				    type, length);
+				tlv_tree = proto_item_add_subtree(tlvi,
+				    ETT_CDP_TLV);
+				proto_tree_add_text(tlv_tree,
+				    offset + TLV_TYPE, 2, "Type: %u", type);
+				proto_tree_add_text(tlv_tree,
+				    offset + TLV_LENGTH, 2, "Length: %u",
+				    length);
+				if (length > 0) {
+					proto_tree_add_text(tlv_tree,
+					    offset + 4, length, "Data");
+				}
 				offset+=length + 4;
 				break;
 			case 1: /* ??? Chassis ID */
-				proto_tree_add_text(cdp_tree, offset + 4,
-				    length - 4, "Chassis ID: %s", &pd[offset+4] );
+				tlvi = proto_tree_add_text(cdp_tree, offset,
+				    length, "Chassis ID: %s",
+				    &pd[offset+4]);
+				tlv_tree = proto_item_add_subtree(tlvi,
+				    ETT_CDP_TLV);
+				proto_tree_add_text(tlv_tree,
+				    offset + TLV_TYPE, 2, "Type: Chassis ID");
+				proto_tree_add_text(tlv_tree,
+				    offset + TLV_LENGTH, 2, "Length: %u",
+				    length);
+				proto_tree_add_text(tlv_tree, offset + 4,
+				    length - 4, "Chassis ID: %s",
+				    &pd[offset+4]);
 				offset+=length;
 				break;
 			case 2:  
-				/* this is quite strange: this tlv contains no data itself but two tlvs which
-                 * calculate the length without the 2 byte type and 2 byte length field
-                 */
-				offset+=4; 
+				/* this is quite strange: this tlv contains
+				   no data itself but two tlvs which
+				   calculate the length without the 2 byte
+				   type and 2 byte length field */
+				tlvi = proto_tree_add_text(cdp_tree, offset,
+				    4, "Type: %u (unknown), second field: %u",
+				    type, length);
+				tlv_tree = proto_item_add_subtree(tlvi,
+				    ETT_CDP_TLV);
+				proto_tree_add_text(tlv_tree,
+				    offset + TLV_TYPE, 2, "Type: %u", type);
+				proto_tree_add_text(tlv_tree,
+				    offset + TLV_LENGTH, 2, "Second field: %u",
+				    length);
+				offset+=4;
 				break;
 			case 3: /* ??? Port  */    
-				proto_tree_add_text(cdp_tree, offset + 4,
-				  length - 4, "Sent through Interface: %s", &pd[offset+4] );
+				tlvi = proto_tree_add_text(cdp_tree, offset,
+				    length, "Sent through Interface: %s",
+				    &pd[offset+4]);
+				tlv_tree = proto_item_add_subtree(tlvi,
+				    ETT_CDP_TLV);
+				proto_tree_add_text(tlv_tree,
+				    offset + TLV_TYPE, 2, "Type: Port");
+				proto_tree_add_text(tlv_tree,
+				    offset + TLV_LENGTH, 2, "Length: %u",
+				    length);
+				proto_tree_add_text(tlv_tree, offset + 4,
+				    length - 4, "Sent through Interface: %s",
+				    &pd[offset+4]);
 				offset+=length;
 				break;
 			case 5: /* ??? IOS Version */
@@ -117,46 +159,61 @@ dissect_cdp(const u_char *pd, int offset, frame_data *fd, proto_tree *tree) {
 				offset+=length;
 				break;
 			case 6: /* ??? platform */
-				
 				stringmem = malloc(length);
 				memset(stringmem, '\0', length);
 				memcpy(stringmem, &pd[offset+4], length - 4 );
-				proto_tree_add_text(cdp_tree, offset + 4, length - 4, 
-                                                     "Platform: %s", stringmem );
+				tlvi = proto_tree_add_text(cdp_tree,
+				    offset, length, "Platform: %s",
+				    stringmem);
+				tlv_tree = proto_item_add_subtree(tlvi,
+				    ETT_CDP_TLV);
+				proto_tree_add_text(tlv_tree,
+				    offset + TLV_TYPE, 2, "Type: Platform");
+				proto_tree_add_text(tlv_tree,
+				    offset + TLV_LENGTH, 2, "Length: %u",
+				    length);
+				proto_tree_add_text(tlv_tree, offset + 4,
+				    length - 4, "Platform: %s", stringmem);
 				free(stringmem);
 				offset+=length;
 				break;
-			case 0x01cc: /* ??? Mgmt Addr */
-				proto_tree_add_text(cdp_tree, offset + 4, length, 
-                                                     "Mgmt IP: %s",
-						     ip_to_str(&pd[offset+4]) );
+			case 0x01cc:
+				/* ??? Mgmt IP Addr; in this one, the "length"
+				   field doesn't include the length of the
+				   type and length fields. */
+				tlvi = proto_tree_add_text(cdp_tree,
+				    offset, length + 4, "Mgmt IP: %s",
+				    ip_to_str(&pd[offset+4]));
+				tlv_tree = proto_item_add_subtree(tlvi,
+				    ETT_CDP_TLV);
+				proto_tree_add_text(tlv_tree,
+				    offset + TLV_TYPE, 2, "Type: Mgmt IP");
+				proto_tree_add_text(tlv_tree,
+				    offset + TLV_LENGTH, 2, "Length: %u",
+				    length);
+				proto_tree_add_text(tlv_tree, offset + 4,
+				    length, "IP address: %s",
+				    ip_to_str(&pd[offset+4]));
 				offset+=length + 4;
 				break;
 			default:
-/*
-				if( type > 512){
-					dissect_data(pd, offset, fd, cdp_tree);
+				tlvi = proto_tree_add_text(cdp_tree, offset,
+				    length, "Type: %u (unknown), length: %u",
+				    type, length);
+				tlv_tree = proto_item_add_subtree(tlvi,
+				    ETT_CDP_TLV);
+				proto_tree_add_text(tlv_tree,
+				    offset + TLV_TYPE, 2, "Type: %u", type);
+				proto_tree_add_text(tlv_tree,
+				    offset + TLV_LENGTH, 2, "Length: %u",
+				    length);
+				if (length > 4) {
+					proto_tree_add_text(tlv_tree,
+					    offset + 4, length - 4, "Data");
+				} else
 					return;
-				}
-*/
-/*
-				proto_tree_add_text(cdp_tree, offset + TLV_TYPE,
-				    2, "Type: %d", type);
-				proto_tree_add_text(cdp_tree, offset + TLV_LENGTH,
-				    2, "Length: %d", length);
-				proto_tree_add_text(cdp_tree, offset + 4,
-				    length - 4, "Data");
-*/
-
-				if (length > 0) {
-					offset+=length;
-				}
-				else {
-					dissect_data(pd, offset, fd, cdp_tree);
-					return;
-				}
+				offset+=length;
 		}
-
 	}
     	dissect_data(pd, offset, fd, cdp_tree);
     }