* 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 <netdissect-stdinc.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 const char tstr[] = "[|cdp]";
-#define CDP_HEADER_LEN 4
-#define CDP_HEADER_OFFSET 2
+#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"},
tptr = pptr; /* temporary pointer */
ND_TCHECK2(*tptr, CDP_HEADER_LEN);
- ND_PRINT((ndo, "CDPv%u, ttl: %us", *tptr, *(tptr + 1)));
+ 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_OFFSET), length));
+ 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_HEADER_LEN); /* read out Type and Length */
- type = EXTRACT_16BITS(tptr);
- len = EXTRACT_16BITS(tptr+CDP_HEADER_OFFSET); /* object length includes the 4 bytes header length */
- if (len < CDP_HEADER_LEN) {
+ 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),
len));
break;
}
- tptr += CDP_HEADER_LEN;
- len -= CDP_HEADER_LEN;
+ tptr += CDP_TLV_HEADER_LEN;
+ len -= CDP_TLV_HEADER_LEN;
ND_TCHECK2(*tptr, len);
if (!ndo->ndo_vflag)
ND_PRINT((ndo, ", Device-ID "));
ND_PRINT((ndo, "'"));
- fn_printn(ndo, tptr, len, NULL);
+ (void)fn_printn(ndo, tptr, len, NULL);
ND_PRINT((ndo, "'"));
break;
case 0x02: /* Address */
break;
case 0x03: /* Port-ID */
ND_PRINT((ndo, "'"));
- fn_printn(ndo, tptr, len, NULL);
+ (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))));
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 identation */
+ if (j == 0x0a) /* lets rework the version string to get a nice indentation */
ND_PRINT((ndo, "\t "));
}
break;
case 0x06: /* Platform */
ND_PRINT((ndo, "'"));
- fn_printn(ndo, tptr, len, NULL);
+ (void)fn_printn(ndo, tptr, len, NULL);
ND_PRINT((ndo, "'"));
break;
case 0x07: /* Prefixes */
break;
case 0x09: /* VTP Mgmt Domain - CDPv2 */
ND_PRINT((ndo, "'"));
- fn_printn(ndo, tptr, len, NULL);
+ (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/univercd/cc/td/doc/product/voice/ata/atarn/186rn21m.htm
+ /* 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, "'"));
- fn_printn(ndo, tptr, len, NULL);
+ (void)fn_printn(ndo, tptr, len, NULL);
ND_PRINT((ndo, "'"));
break;
case 0x16: /* System Object ID - not documented */
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, "/"));
- fn_printn(ndo, tptr + 1, len - 1, NULL);
+ (void)fn_printn(ndo, tptr + 1, len - 1, NULL);
}
break;
default:
{
int pt, pl, al, num;
const u_char *endp = p + l;
-#ifdef INET6
static const u_char prot_ipv6[] = {
0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00, 0x86, 0xdd
};
-#endif
- ND_TCHECK2(*p, 2);
+ ND_TCHECK2(*p, 4);
+ if (p + 4 > endp)
+ goto trunc;
num = EXTRACT_32BITS(p);
p += 4;
ND_PRINT((ndo, "IPv4 (%u) %s", num, ipaddr_string(ndo, p)));
p += 4;
}
-#ifdef INET6
else if (pt == PT_IEEE_802_2 && pl == 8 &&
memcmp(p, prot_ipv6, 8) == 0 && al == 16) {
/*
ND_PRINT((ndo, "IPv6 (%u) %s", num, ip6addr_string(ndo, p)));
p += al;
}
-#endif
else {
/*
* Generic case: just print raw data
projects / tcpdump / blobdiff