X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/37af9b50dbba221dd532a348a97b54ddea288121..refs/pull/482/head:/print-cdp.c

diff --git a/print-cdp.c b/print-cdp.c
index 798b8f06..96ef143b 100644
--- a/print-cdp.c
+++ b/print-cdp.c
@@ -24,152 +24,377 @@
  *    http://www.cisco.com/univercd/cc/td/doc/product/lan/trsrb/frames.htm
  */
 
-#ifndef lint
-static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-cdp.c,v 1.2 2000-05-16 23:54:55 assar Exp $";
-#endif
-
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
-#include <sys/param.h>
-#include <sys/time.h>
-
-#include <netinet/in.h>
+#include <netdissect-stdinc.h>
 
-#include <ctype.h>
-#include <netdb.h>
-#include <stdio.h>
 #include <string.h>
 
-#include "interface.h"
+#include "netdissect.h"
 #include "addrtoname.h"
-#include "extract.h"			/* must come after interface.h */
+#include "extract.h"
+#include "nlpid.h"
 
-static void cdp_print_addr( const u_char * p, int l );
-static void cdp_print_prefixes( const u_char * p, int l );
+static const char tstr[] = "[|cdp]";
 
-/*
- * Returns non-zero IFF it succeeds in printing the header
- */
-void
-cdp_print(const u_char *p, u_int length, u_int caplen,
-	  const u_char *esrc, const u_char *edst)
-{
-	int i;
-	int type, len;
+#define CDP_HEADER_LEN             4
+#define CDP_HEADER_VERSION_OFFSET  0
+#define CDP_HEADER_TTL_OFFSET      1
+#define CDP_HEADER_CHECKSUM_OFFSET 2
+
+#define CDP_TLV_HEADER_LEN  4
+#define CDP_TLV_TYPE_OFFSET 0
+#define CDP_TLV_LEN_OFFSET  2
+
+static const 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}
+};
 
-	/* Cisco Discovery Protocol */
+static const 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(netdissect_options *, const u_char *, int);
+static int cdp_print_prefixes(netdissect_options *, const u_char *, int);
+static unsigned long cdp_get_number(const u_char *, int);
+
+void
+cdp_print(netdissect_options *ndo,
+          const u_char *pptr, u_int length, u_int caplen)
+{
+	int type, len, i, j;
+	const u_char *tptr;
 
-	if ( caplen < 12 ) {
-		(void)printf("[|cdp]");
+	if (caplen < CDP_HEADER_LEN) {
+		ND_PRINT((ndo, "%s", tstr));
 		return;
 	}
 
-	i=8;		/* CDP data starts at offset 8 */
-	printf ("CDP v%d, ttl=%ds", p[i], p[i+1] );
-	i+=4;		/* skip version, TTL and chksum */
+	tptr = pptr; /* temporary pointer */
 
-	while (i < length) {
-	    if ( i+4 > caplen ) {
-		printf("[!cdp]");
-		return;
-	    }
-	    type = (p[i]<<8) + p[i+1];
-	    len  = (p[i+2]<<8) + p[i+3];
+	ND_TCHECK2(*tptr, CDP_HEADER_LEN);
+	ND_PRINT((ndo, "CDPv%u, ttl: %us", *(tptr + CDP_HEADER_VERSION_OFFSET),
+					   *(tptr + CDP_HEADER_TTL_OFFSET)));
+	if (ndo->ndo_vflag)
+		ND_PRINT((ndo, ", checksum: 0x%04x (unverified), length %u", EXTRACT_16BITS(tptr+CDP_HEADER_CHECKSUM_OFFSET), length));
+	tptr += CDP_HEADER_LEN;
+
+	while (tptr < (pptr+length)) {
+		ND_TCHECK2(*tptr, CDP_TLV_HEADER_LEN); /* read out Type and Length */
+		type = EXTRACT_16BITS(tptr+CDP_TLV_TYPE_OFFSET);
+		len  = EXTRACT_16BITS(tptr+CDP_TLV_LEN_OFFSET); /* object length includes the 4 bytes header length */
+		if (len < CDP_TLV_HEADER_LEN) {
+		    if (ndo->ndo_vflag)
+			ND_PRINT((ndo, "\n\t%s (0x%02x), TLV length: %u byte%s (too short)",
+			       tok2str(cdp_tlv_values,"unknown field type", type),
+			       type,
+			       len,
+			       PLURAL_SUFFIX(len))); /* plural */
+		    else
+			ND_PRINT((ndo, ", %s TLV length %u too short",
+			       tok2str(cdp_tlv_values,"unknown field type", type),
+			       len));
+		    break;
+		}
+		tptr += CDP_TLV_HEADER_LEN;
+		len -= CDP_TLV_HEADER_LEN;
 
-	    if ( vflag )
-		printf( "\n\t%02x/%02x", type, len );
-	    else
-		printf( "\n\t" );
+		ND_TCHECK2(*tptr, len);
 
-	    if ( i+len > caplen ) {
-		printf("[!cdp]");
-		return;
-	    }
-
-	    switch( type )
-	    {
-	    case 0x01:
-		printf( " DevID '%.*s'", len-4, p+i+4 );
-		break;
-	    case 0x02:
-		printf( " Addr" );
-		cdp_print_addr( p+i+4, len-4 );
-		break;
-	    case 0x03:
-		printf( " PortID '%.*s'", len-4, p+i+4 );
-		break;
-	    case 0x04:
-		printf( " CAP 0x%02x", (unsigned) p[i+7] );
-		break;
-	    case 0x05:
-		if ( vflag )
-		    printf( " Version:\n%.*s", len-4, p+i+4 );
-		else
-		    printf( " Version: (suppressed)" );
-		break;
-	    case 0x06:
-		printf( " Platform: '%.*s'", len-4, p+i+4 );
-		break;
-	    case 0x07:
-	        cdp_print_prefixes( p+i+4, len-4 );
-		break;
-	    default:
-		printf( " unknown field type %02x, len %d", type, len );
-	    }
-	    i+=len;
+		if (ndo->ndo_vflag || type == 1) { /* in non-verbose mode just print Device-ID */
+
+		    if (ndo->ndo_vflag)
+			ND_PRINT((ndo, "\n\t%s (0x%02x), value length: %u byte%s: ",
+			       tok2str(cdp_tlv_values,"unknown field type", type),
+			       type,
+			       len,
+			       PLURAL_SUFFIX(len))); /* plural */
 
+		    switch (type) {
+
+		    case 0x01: /* Device-ID */
+			if (!ndo->ndo_vflag)
+			    ND_PRINT((ndo, ", Device-ID "));
+			ND_PRINT((ndo, "'"));
+			(void)fn_printn(ndo, tptr, len, NULL);
+			ND_PRINT((ndo, "'"));
+			break;
+		    case 0x02: /* Address */
+			if (cdp_print_addr(ndo, tptr, len) < 0)
+			    goto trunc;
+			break;
+		    case 0x03: /* Port-ID */
+			ND_PRINT((ndo, "'"));
+			(void)fn_printn(ndo, tptr, len, NULL);
+			ND_PRINT((ndo, "'"));
+			break;
+		    case 0x04: /* Capabilities */
+			if (len < 4)
+			    goto trunc;
+			ND_PRINT((ndo, "(0x%08x): %s",
+			       EXTRACT_32BITS(tptr),
+			       bittok2str(cdp_capability_values, "none", EXTRACT_32BITS(tptr))));
+			break;
+		    case 0x05: /* Version */
+			ND_PRINT((ndo, "\n\t  "));
+			for (i=0;i<len;i++) {
+			    j = *(tptr+i);
+			    ND_PRINT((ndo, "%c", j));
+			    if (j == 0x0a) /* lets rework the version string to get a nice indentation */
+				ND_PRINT((ndo, "\t  "));
+			}
+			break;
+		    case 0x06: /* Platform */
+			ND_PRINT((ndo, "'"));
+			(void)fn_printn(ndo, tptr, len, NULL);
+			ND_PRINT((ndo, "'"));
+			break;
+		    case 0x07: /* Prefixes */
+			if (cdp_print_prefixes(ndo, tptr, len) < 0)
+			    goto trunc;
+			break;
+		    case 0x08: /* Protocol Hello Option - not documented */
+			break;
+		    case 0x09: /* VTP Mgmt Domain  - CDPv2 */
+			ND_PRINT((ndo, "'"));
+			(void)fn_printn(ndo, tptr, len, NULL);
+			ND_PRINT((ndo, "'"));
+			break;
+		    case 0x0a: /* Native VLAN ID - CDPv2 */
+			if (len < 2)
+			    goto trunc;
+			ND_PRINT((ndo, "%d", EXTRACT_16BITS(tptr)));
+			break;
+		    case 0x0b: /* Duplex - CDPv2 */
+			if (len < 1)
+			    goto trunc;
+			ND_PRINT((ndo, "%s", *(tptr) ? "full": "half"));
+			break;
+
+		    /* http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cata/186/2_12_m/english/release/notes/186rn21m.html
+		     * plus more details from other sources
+		     */
+		    case 0x0e: /* ATA-186 VoIP VLAN request - incomplete doc. */
+			if (len < 3)
+			    goto trunc;
+			ND_PRINT((ndo, "app %d, vlan %d", *(tptr), EXTRACT_16BITS(tptr + 1)));
+			break;
+		    case 0x10: /* ATA-186 VoIP VLAN assignment - incomplete doc. */
+			ND_PRINT((ndo, "%1.2fW", cdp_get_number(tptr, len) / 1000.0));
+			break;
+		    case 0x11: /* MTU - not documented */
+			if (len < 4)
+			    goto trunc;
+			ND_PRINT((ndo, "%u bytes", EXTRACT_32BITS(tptr)));
+			break;
+		    case 0x12: /* AVVID trust bitmap - not documented */
+			if (len < 1)
+			    goto trunc;
+			ND_PRINT((ndo, "0x%02x", *(tptr)));
+			break;
+		    case 0x13: /* AVVID untrusted port CoS - not documented */
+			if (len < 1)
+			    goto trunc;
+			ND_PRINT((ndo, "0x%02x", *(tptr)));
+			break;
+		    case 0x14: /* System Name - not documented */
+			ND_PRINT((ndo, "'"));
+			(void)fn_printn(ndo, tptr, len, NULL);
+			ND_PRINT((ndo, "'"));
+			break;
+		    case 0x16: /* System Object ID - not documented */
+			if (cdp_print_addr(ndo, tptr, len) < 0)
+				goto trunc;
+			break;
+		    case 0x17: /* Physical Location - not documented */
+			if (len < 1)
+			    goto trunc;
+			ND_PRINT((ndo, "0x%02x", *(tptr)));
+			if (len > 1) {
+				ND_PRINT((ndo, "/"));
+				(void)fn_printn(ndo, tptr + 1, len - 1, NULL);
+			}
+			break;
+		    default:
+			print_unknown_data(ndo, tptr, "\n\t  ", len);
+			break;
+		    }
+		}
+		tptr = tptr+len;
 	}
+	if (ndo->ndo_vflag < 1)
+	    ND_PRINT((ndo, ", length %u", caplen));
+
+	return;
+trunc:
+	ND_PRINT((ndo, "%s", tstr));
 }
 
-static void
-cdp_print_addr( const u_char * p, int l )
+/*
+ * Protocol type values.
+ *
+ * PT_NLPID means that the protocol type field contains an OSI NLPID.
+ *
+ * PT_IEEE_802_2 means that the protocol type field contains an IEEE 802.2
+ * LLC header that specifies that the payload is for that protocol.
+ */
+#define PT_NLPID		1	/* OSI NLPID */
+#define PT_IEEE_802_2		2	/* IEEE 802.2 LLC header */
+
+static int
+cdp_print_addr(netdissect_options *ndo,
+	       const u_char * p, int l)
 {
-	int pl, al, num;
-	const u_char * endp = p+l;
-
-	num = (p[0] << 24) + (p[1]<<16) + (p[2]<<8)+ p[3];
-	p+=4;
-
-	printf(" (%d): ", num );
-
-	while( p < endp && num >= 0) {
-		pl=*(p+1);
-		p+=2; 
-
-		/* special case: IPv4, protocol type=0xcc, addr. length=4 */
-		if ( pl == 1 && *p == 0xcc && 
-		     p[1] == 0 && p[2] == 4 ) {
-			p+=3;
-
-			printf( "IPv4 %d.%d.%d.%d ", p[0], p[1], p[2], p[3] );
-			p+=4;
-		} else {	/* generic case: just print raw data */
-			printf("pt=0x%02x, pl=%d, pb=", *(p-2), pl);
-			while( pl-- > 0 )
-				printf( " %02x", *p++);
-			al=(*p << 8) + *(p+1);
-			printf( ", al=%d, a=", al );
-			p+=2; 
-			while( al-- > 0 )
-				printf( " %02x", *p++);
+	int pt, pl, al, num;
+	const u_char *endp = p + l;
+	static const u_char prot_ipv6[] = {
+		0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00, 0x86, 0xdd
+	};
+
+	ND_TCHECK2(*p, 4);
+	if (p + 4 > endp)
+		goto trunc;
+	num = EXTRACT_32BITS(p);
+	p += 4;
+
+	while (p < endp && num >= 0) {
+		ND_TCHECK2(*p, 2);
+		if (p + 2 > endp)
+			goto trunc;
+		pt = p[0];		/* type of "protocol" field */
+		pl = p[1];		/* length of "protocol" field */
+		p += 2;
+
+		ND_TCHECK2(p[pl], 2);
+		if (p + pl + 2 > endp)
+			goto trunc;
+		al = EXTRACT_16BITS(&p[pl]);	/* address length */
+
+		if (pt == PT_NLPID && pl == 1 && *p == NLPID_IP && al == 4) {
+			/*
+			 * IPv4: protocol type = NLPID, protocol length = 1
+			 * (1-byte NLPID), protocol = 0xcc (NLPID for IPv4),
+			 * address length = 4
+			 */
+			p += 3;
+
+			ND_TCHECK2(*p, 4);
+			if (p + 4 > endp)
+				goto trunc;
+			ND_PRINT((ndo, "IPv4 (%u) %s", num, ipaddr_string(ndo, p)));
+			p += 4;
+		}
+		else if (pt == PT_IEEE_802_2 && pl == 8 &&
+		    memcmp(p, prot_ipv6, 8) == 0 && al == 16) {
+			/*
+			 * IPv6: protocol type = IEEE 802.2 header,
+			 * protocol length = 8 (size of LLC+SNAP header),
+			 * protocol = LLC+SNAP header with the IPv6
+			 * Ethertype, address length = 16
+			 */
+			p += 10;
+			ND_TCHECK2(*p, al);
+			if (p + al > endp)
+				goto trunc;
+
+			ND_PRINT((ndo, "IPv6 (%u) %s", num, ip6addr_string(ndo, p)));
+			p += al;
+		}
+		else {
+			/*
+			 * Generic case: just print raw data
+			 */
+			ND_TCHECK2(*p, pl);
+			if (p + pl > endp)
+				goto trunc;
+			ND_PRINT((ndo, "pt=0x%02x, pl=%d, pb=", *(p - 2), pl));
+			while (pl-- > 0)
+				ND_PRINT((ndo, " %02x", *p++));
+			ND_TCHECK2(*p, 2);
+			if (p + 2 > endp)
+				goto trunc;
+			al = (*p << 8) + *(p + 1);
+			ND_PRINT((ndo, ", al=%d, a=", al));
+			p += 2;
+			ND_TCHECK2(*p, al);
+			if (p + al > endp)
+				goto trunc;
+			while (al-- > 0)
+				ND_PRINT((ndo, " %02x", *p++));
 		}
-		printf("  ");
 		num--;
+		if (num)
+			ND_PRINT((ndo, " "));
 	}
+
+	return 0;
+
+trunc:
+	return -1;
 }
 
 
-static void
-cdp_print_prefixes( const u_char * p, int l )
+static int
+cdp_print_prefixes(netdissect_options *ndo,
+		   const u_char * p, int l)
 {
-    printf( " IPv4 Prefixes (%d):", l/5 );
+	if (l % 5)
+		goto trunc;
+
+	ND_PRINT((ndo, " IPv4 Prefixes (%d):", l / 5));
+
+	while (l > 0) {
+		ND_PRINT((ndo, " %u.%u.%u.%u/%u", p[0], p[1], p[2], p[3], p[4]));
+		l -= 5;
+		p += 5;
+	}
 
-    while(l > 0) {
-	printf( " %d.%d.%d.%d/%d", p[0], p[1], p[2], p[3], p[4] );
-	l-=5; p+=5;
+	return 0;
+
+trunc:
+	return -1;
+}
+
+/* read in a <n>-byte number, MSB first
+ * (of course this can handle max sizeof(long))
+ */
+static unsigned long cdp_get_number(const u_char * p, int l)
+{
+    unsigned long res=0;
+    while( l>0 )
+    {
+	res = (res<<8) + *p;
+	p++; l--;
     }
+    return res;
 }