CDP rework

  - multiline output +identation (behind v option)
  - removal of EXTRACT_ lookalikes
  - dissecting the Capabilities field
  - more use of tok2str()

1 files changed, 136 insertions, 95 deletions

diff --git a/print-cdp.c b/print-cdp.c
index 72f9ea85..4948cf89 100644
--- a/print-cdp.c
+++ b/print-cdp.c
@@ -26,7 +26,7 @@
 
 #ifndef lint
 static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-cdp.c,v 1.17 2002-09-05 21:25:38 guy Exp $";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-cdp.c,v 1.18 2002-11-10 21:32:53 hannes Exp $";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -42,139 +42,178 @@ static const char rcsid[] =
 #include "addrtoname.h"
 #include "extract.h"			/* must come after interface.h */
 
+#define CDP_HEADER_LEN  4
+
+static struct tok cdp_tlv_values[] = {
+    { 0x01,             "Device-ID"},
+    { 0x02,             "Address"},
+    { 0x03,             "Port-ID"},
+    { 0x04,             "Capability"},
+    { 0x05,             "Version String"},
+    { 0x06,             "Platform"},
+    { 0x07,             "Prefixes"},
+    { 0x08,             "Protocol-Hello option"},
+    { 0x09,             "VTP Management Domain"},
+    { 0x0a,             "Native VLAN ID"},
+    { 0x0b,             "Duplex"},
+    { 0x0e,             "ATA-186 VoIP VLAN request"},
+    { 0x0f,             "ATA-186 VoIP VLAN assignment"},
+    { 0x10,             "power consumption"},
+    { 0x11,             "MTU"},
+    { 0x12,             "AVVID trust bitmap"},
+    { 0x13,             "AVVID untrusted ports CoS"},
+    { 0x14,             "System Name"},
+    { 0x15,             "System Object ID (not decoded)"},
+    { 0x16,             "Management Addresses"},
+    { 0x17,             "Physical Location"},
+    { 0, NULL}
+};
+
+static struct tok cdp_capability_values[] = {
+    { 0x01,             "Router" },
+    { 0x02,             "Transparent Bridge" },
+    { 0x04,             "Source Route Bridge" },
+    { 0x08,             "L2 Switch" },
+    { 0x10,             "L3 capable" },
+    { 0x20,             "IGMP snooping" },
+    { 0x40,             "L1 capable" },
+    { 0, NULL }
+};
+
 static int cdp_print_addr(const u_char *, int);
 static int cdp_print_prefixes(const u_char *, int);
 static unsigned long cdp_get_number(const u_char *, int);
 
 void
-cdp_print(const u_char *p, u_int length, u_int caplen)
+cdp_print(const u_char *pptr, u_int length, u_int caplen)
 {
-	u_int i;
-	int type, len;
-
-	/* Cisco Discovery Protocol */
+	int type, len, i, j;
+        const u_char *tptr;
 
-	if (caplen < 4) {
+	if (caplen < CDP_HEADER_LEN) {
 		(void)printf("[|cdp]");
 		return;
 	}
 
-	i = 0;		/* CDP data starts at offset 0 */
-	printf("CDP v%u, ttl=%us", p[i], p[i + 1]);
-	i += 4;		/* skip version, TTL and chksum */
+        tptr = pptr; /* temporary pointer */
 
-	while (i < length) {
-		if (i + 4 > caplen)
-			goto trunc;
-		type = (p[i] <<  8) + p[i + 1];
-		len  = (p[i + 2] << 8) + p[i + 3];
+        if (!TTEST2(*tptr, CDP_HEADER_LEN))
+                goto trunc;
+	printf("CDP v%u, ttl: %us", *tptr, *(tptr+1));
+        if (vflag)
+                printf(", checksum: %u (unverified)", EXTRACT_16BITS(tptr));
+	tptr += CDP_HEADER_LEN;
 
-		if (vflag > 1)
-			printf("\n\t");
+	while (tptr < (pptr+length)) {
 
-		if (vflag)
-			printf(" %02x/%02x", type, len);
+                if (!TTEST2(*tptr, 4)) /* read out Type and Length */
+                    goto trunc;
+		type = EXTRACT_16BITS(tptr);
+		len  = EXTRACT_16BITS(tptr+2); /* object length includes the 4 bytes header length */
+                tptr += 4;
+                len -= 4;
 
-		if (i + len > caplen)
+		if (!TTEST2(*tptr, len))
 			goto trunc;
 
-		switch (type) {
-		case 0x00:
-			printf(" Goodbye");
-			break;
-		case 0x01:
-			printf(" DevID '%.*s'", len - 4, p + i + 4);
-			break;
-		case 0x02:
-			printf(" Addr");
-			if (cdp_print_addr(p + i + 4, len - 4) < 0)
-				goto trunc;
-			break;
-		case 0x03:
-			printf(" PortID '%.*s'", len - 4, p + i + 4);
+                if (vflag || type == 1) { /* in non-verbose mode just print Device-ID */
+
+                    if (vflag)
+                        printf("\n\t%s (0x%02x), length: %u byte%s: ",
+                               tok2str(cdp_tlv_values,"unknown field type", type),
+                               type,
+                               len,
+                               len>1 ? "s" : ""); /* plural */
+
+                    switch (type) {
+
+                    case 0x01: /* Device-ID */
+                        if (!vflag)
+                            printf(", Device-ID '%.*s'", len, tptr);
+                        else
+                            printf("'%.*s'", len, tptr);
 			break;
-		case 0x04:
-			printf(" CAP 0x%02x", (unsigned) p[i + 7]);
+                    case 0x02: /* Address */
+                        if (cdp_print_addr(tptr, len) < 0)
+                            goto trunc;
 			break;
-		case 0x05:
-			if (vflag > 1)
-				printf(" Version:\n%.*s", len - 4, p + i + 4);
-			else
-				printf(" Version: (suppressed)");
+                    case 0x03: /* Port-ID */
+			printf("'%.*s'", len, tptr);
 			break;
-		case 0x06:
-			printf(" Platform: '%.*s'", len - 4, p + i + 4);
+                    case 0x04: /* Capabilities */
+			printf("(0x%02x): %s",
+                               *(tptr + 3),
+                               bittok2str(cdp_capability_values, "none",*(tptr + 3)));
 			break;
-		case 0x07:
-			if (cdp_print_prefixes(p + i + 4, len - 4) < 0)
-				goto trunc;
+                    case 0x05: /* Version */
+                        printf("\n\t  ");
+                        for (i=0;i<len;i++) {
+                            j = *(tptr+i);
+                            putchar(j);
+                            if (j == 0x0a) /* lets rework the version string to get a nice identation */
+                                printf("\t  ");
+                        }
 			break;
-		case 0x08:		/* guess - not documented */
-			printf(" Protocol-Hello option" );
+                    case 0x06: /* Platform */
+			printf("'%.*s'", len, tptr);
 			break;
-		case 0x09:		/* guess - not documented */
-			printf(" VTP Management Domain: '%.*s'", len - 4,
-			    p + i + 4);
+                    case 0x07: /* Prefixes */
+			if (cdp_print_prefixes(tptr, len) < 0)
+                            goto trunc;
 			break;
-		case 0x0a:		/* guess - not documented */
-			printf(" Native VLAN ID: %d",
-			    (p[i + 4] << 8) + p[i + 4 + 1] );
+                    case 0x08: /* Protocol Hello Option - not documented */
 			break;
-		case 0x0b:		/* guess - not documented */
-			printf(" Duplex: %s", p[i + 4] ? "full": "half");
+                    case 0x09: /* VTP Mgmt Domain  - not documented */
+			printf("'%.*s'", len,tptr);
 			break;
-/* http://www.cisco.com/univercd/cc/td/doc/product/voice/ata/atarn/186rn21m.htm
- * plus more details from other sources
- */
-		case 0x0e:		/* incomplete doc. */
-			printf(" ATA-186 VoIP VLAN request, app %d, vlan %d",
-				p[i + 4], EXTRACT_16BITS(&p[i+4+1]));
+                    case 0x0a: /* Native VLAN ID - not documented */
+			printf("%d",EXTRACT_16BITS(tptr));
 			break;
-		case 0x0f:		/* incomplete doc. */
-			printf(" ATA-186 VoIP VLAN assignment" );
+                    case 0x0b: /* Duplex - not documented */
+			printf("%s", *(tptr) ? "full": "half");
 			break;
-		case 0x10:		/* incomplete doc. */
-			printf(" power consumption: %1.2fW",
-				cdp_get_number(p+i+4, len-4)/1000.0 );
+
+                    /* http://www.cisco.com/univercd/cc/td/doc/product/voice/ata/atarn/186rn21m.htm
+                     * plus more details from other sources
+                     */
+                    case 0x0e: /* ATA-186 VoIP VLAN request - incomplete doc. */
+			printf("app %d, vlan %d",
+                               *(tptr), EXTRACT_16BITS(tptr+1));
 			break;
-		case 0x11:		/* guess - not documented */
-			printf(" MTU %u bytes", EXTRACT_32BITS(&p[i+4]));
+                    case 0x10: /* ATA-186 VoIP VLAN assignment - incomplete doc. */
+			printf("%1.2fW",
+                               cdp_get_number(tptr, len)/1000.0 );
 			break;
-		case 0x12:		/* guess - not documented */
-			printf(" AVVID trust bitmap 0x%02x", p[i+4] );
+                    case 0x11: /* MTU - not documented */
+			printf("%u bytes", EXTRACT_32BITS(tptr));
 			break;
-		case 0x13:		/* guess - not documented */
-			printf(" AVVID untrusted ports CoS: 0x%02x", p[i+4]);
+                    case 0x12: /* AVVID trust bitmap - not documented */
+			printf("0x%02x", *(tptr) );
 			break;
-		case 0x14:		/* guess - not documented */
-			printf(" System Name: '%.*s'", len - 4,
-				p + i + 4);
+                    case 0x13: /* AVVID untrusted port CoS - not documented */
+			printf("0x%02x", *(tptr));
 			break;
-		case 0x15:		/* guess - not documented */
-			printf(" System Object ID (not decoded) ");	/* TODO */
+                    case 0x14: /* System Name - not documented */
+			printf("'%.*s'", len, tptr);
 			break;
-		case 0x16:		/* guess - not documented */
-			printf(" Management Addresses: ");
-			if (cdp_print_addr(p + i + 4, len - 4) < 0)
+                    case 0x16: /* System Object ID - not documented */
+			if (cdp_print_addr(tptr, len) < 0)
 				goto trunc;
 			break;
-		case 0x17:		/* guess - not documented */
-			printf(" Physical Location: 0x%02x/%.*s",
-				p[i+4], len - 5, p + i + 5 );
+                    case 0x17: /* Physical Location - not documented */
+			printf("0x%02x/%.*s", *(tptr), len - 1, tptr + 1 );
 			break;
-		default:
-			printf(" unknown field type %02x, len %d", type, len);
+                    default:
+                        print_unknown_data(tptr,"\n\t  ",len);
 			break;
-		}
-
+                    }
+                }
 		/* avoid infinite loop */
 		if (len == 0)
 			break;
-		i += len;
+		tptr = tptr+len;
 	}
-
 	return;
-
 trunc:
 	printf("[|cdp]");
 }
@@ -204,8 +243,6 @@ cdp_print_addr(const u_char * p, int l)
 	num = EXTRACT_32BITS(p);
 	p += 4;
 
-	printf(" (%d): ", num);
-
 	while (p < endp && num >= 0) {
 		if (p + 2 > endp)
 			goto trunc;
@@ -227,7 +264,9 @@ cdp_print_addr(const u_char * p, int l)
 
 			if (p + 4 > endp)
 				goto trunc;
-			printf("IPv4 %u.%u.%u.%u", p[0], p[1], p[2], p[3]);
+			printf("IPv4 (%u) %s",
+                               num,
+                               ipaddr_string(p));
 			p += 4;
 		}
 #ifdef INET6
@@ -243,7 +282,9 @@ cdp_print_addr(const u_char * p, int l)
 			if (p + al > endp)
 				goto trunc;
 
-			printf("IPv6 %s", ip6addr_string(p));
+			printf("IPv6 (%u) %s",
+                               num,
+                               ip6addr_string(p));
 			p += al;
 		}
 #endif