* http://www.cisco.com/univercd/cc/td/doc/product/lan/trsrb/frames.htm
*/
+/* \summary: Cisco Discovery Protocol (CDP) printer */
+
#ifdef HAVE_CONFIG_H
-#include "config.h"
+#include <config.h>
#endif
-#include <tcpdump-stdinc.h>
+#include "netdissect-stdinc.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 const char tstr[] = "[|cdp]";
-#define CDP_HEADER_LEN 4
+#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"},
{ 0x09, "VTP Management Domain"},
{ 0x0a, "Native VLAN ID"},
{ 0x0b, "Duplex"},
- { 0x0e, "ATA-186 VoIP VLAN request"},
- { 0x0f, "ATA-186 VoIP VLAN assignment"},
+ { 0x0e, "ATA-186 VoIP VLAN assignment"},
+ { 0x0f, "ATA-186 VoIP VLAN request"},
{ 0x10, "power consumption"},
{ 0x11, "MTU"},
{ 0x12, "AVVID trust bitmap"},
{ 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);
+static int cdp_print_addr(netdissect_options *, const u_char *, u_int);
+static int cdp_print_prefixes(netdissect_options *, const u_char *, u_int);
+static unsigned int cdp_get_number(netdissect_options *, const u_char *, u_int);
void
-cdp_print(const u_char *pptr, u_int length, u_int caplen)
+cdp_print(netdissect_options *ndo,
+ const u_char *pptr, u_int length, u_int caplen)
{
- int type, len, i, j;
- const u_char *tptr;
+ u_int type, len, i;
+ const u_char *tptr;
+ ndo->ndo_protocol = "cdp";
if (caplen < CDP_HEADER_LEN) {
- printf("%s", tstr);
+ nd_print_trunc(ndo);
return;
}
- tptr = pptr; /* temporary pointer */
+ tptr = pptr; /* temporary pointer */
- if (!TTEST2(*tptr, CDP_HEADER_LEN))
- goto trunc;
- printf("CDPv%u, ttl: %us", *tptr, *(tptr+1));
- if (vflag)
- printf(", checksum: %u (unverified), length %u", EXTRACT_16BITS(tptr), length);
+ ND_TCHECK_LEN(tptr, CDP_HEADER_LEN);
+ ND_PRINT("CDPv%u, ttl: %us",
+ GET_U_1((tptr + CDP_HEADER_VERSION_OFFSET)),
+ GET_U_1(tptr + CDP_HEADER_TTL_OFFSET));
+ if (ndo->ndo_vflag)
+ ND_PRINT(", checksum: 0x%04x (unverified), length %u",
+ GET_BE_U_2(tptr + CDP_HEADER_CHECKSUM_OFFSET),
+ length);
tptr += CDP_HEADER_LEN;
while (tptr < (pptr+length)) {
+ ND_TCHECK_LEN(tptr, CDP_TLV_HEADER_LEN); /* read out Type and Length */
+ type = GET_BE_U_2(tptr + CDP_TLV_TYPE_OFFSET);
+ len = GET_BE_U_2(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("\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(", %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 (!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 (!TTEST2(*tptr, len))
- goto trunc;
+ ND_TCHECK_LEN(tptr, len);
- if (vflag || type == 1) { /* in non-verbose mode just print Device-ID */
+ if (ndo->ndo_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,
- PLURAL_SUFFIX(len)); /* plural */
+ if (ndo->ndo_vflag)
+ ND_PRINT("\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) {
+ switch (type) {
- case 0x01: /* Device-ID */
- if (!vflag)
- printf(", Device-ID ");
- printf("'");
- fn_printn(tptr, len, NULL);
- printf("'");
+ case 0x01: /* Device-ID */
+ if (!ndo->ndo_vflag)
+ ND_PRINT(", Device-ID ");
+ ND_PRINT("'");
+ (void)nd_printn(ndo, tptr, len, NULL);
+ ND_PRINT("'");
break;
- case 0x02: /* Address */
- if (cdp_print_addr(tptr, len) < 0)
- goto trunc;
+ case 0x02: /* Address */
+ if (cdp_print_addr(ndo, tptr, len) < 0)
+ goto trunc;
break;
- case 0x03: /* Port-ID */
- printf("'");
- fn_printn(tptr, len, NULL);
- printf("'");
+ case 0x03: /* Port-ID */
+ ND_PRINT("'");
+ (void)nd_printn(ndo, tptr, len, NULL);
+ ND_PRINT("'");
break;
- case 0x04: /* Capabilities */
- printf("(0x%08x): %s",
- EXTRACT_32BITS(tptr),
- bittok2str(cdp_capability_values, "none",EXTRACT_32BITS(tptr)));
+ case 0x04: /* Capabilities */
+ if (len < 4)
+ goto trunc;
+ ND_PRINT("(0x%08x): %s",
+ GET_BE_U_4(tptr),
+ bittok2str(cdp_capability_values, "none", GET_BE_U_4(tptr)));
break;
- 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 ");
- }
+ case 0x05: /* Version */
+ ND_PRINT("\n\t ");
+ for (i=0;i<len;i++) {
+ u_char c;
+
+ c = GET_U_1(tptr + i);
+ if (c == '\n') /* lets rework the version string to
+ get a nice indentation */
+ ND_PRINT("\n\t ");
+ else
+ fn_print_char(ndo, c);
+ }
break;
- case 0x06: /* Platform */
- printf("'");
- fn_printn(tptr, len, NULL);
- printf("'");
+ case 0x06: /* Platform */
+ ND_PRINT("'");
+ (void)nd_printn(ndo, tptr, len, NULL);
+ ND_PRINT("'");
break;
- case 0x07: /* Prefixes */
- if (cdp_print_prefixes(tptr, len) < 0)
- goto trunc;
+ case 0x07: /* Prefixes */
+ if (cdp_print_prefixes(ndo, tptr, len) < 0)
+ goto trunc;
break;
- case 0x08: /* Protocol Hello Option - not documented */
+ case 0x08: /* Protocol Hello Option - not documented */
break;
- case 0x09: /* VTP Mgmt Domain - not documented */
- printf("'");
- fn_printn(tptr, len, NULL);
- printf("'");
+ case 0x09: /* VTP Mgmt Domain - CDPv2 */
+ ND_PRINT("'");
+ (void)nd_printn(ndo, tptr, len, NULL);
+ ND_PRINT("'");
break;
- case 0x0a: /* Native VLAN ID - not documented */
- printf("%d",EXTRACT_16BITS(tptr));
+ case 0x0a: /* Native VLAN ID - CDPv2 */
+ if (len < 2)
+ goto trunc;
+ ND_PRINT("%u", GET_BE_U_2(tptr));
break;
- case 0x0b: /* Duplex - not documented */
- printf("%s", *(tptr) ? "full": "half");
+ case 0x0b: /* Duplex - CDPv2 */
+ if (len < 1)
+ goto trunc;
+ ND_PRINT("%s", GET_U_1(tptr) ? "full": "half");
break;
- /* 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));
+ /* 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
+ *
+ * There are apparently versions of the request with both
+ * 2 bytes and 3 bytes of value. The 3 bytes of value
+ * appear to be a 1-byte application type followed by a
+ * 2-byte VLAN ID; the 2 bytes of value are unknown
+ * (they're 0x20 0x00 in some captures I've seen; that
+ * is not a valid VLAN ID, as VLAN IDs are 12 bits).
+ *
+ * The replies all appear to be 3 bytes long.
+ */
+ case 0x0e: /* ATA-186 VoIP VLAN assignment - incomplete doc. */
+ if (len < 3)
+ goto trunc;
+ ND_PRINT("app %u, vlan %u", GET_U_1(tptr),
+ GET_BE_U_2(tptr + 1));
+ break;
+ case 0x0f: /* ATA-186 VoIP VLAN request - incomplete doc. */
+ if (len < 2)
+ goto trunc;
+ if (len == 2)
+ ND_PRINT("unknown 0x%04x", GET_BE_U_2(tptr));
+ else
+ ND_PRINT("app %u, vlan %u", GET_U_1(tptr),
+ GET_BE_U_2(tptr + 1));
break;
- case 0x10: /* ATA-186 VoIP VLAN assignment - incomplete doc. */
- printf("%1.2fW",
- cdp_get_number(tptr, len)/1000.0 );
+ case 0x10: /* Power - not documented */
+ ND_PRINT("%1.2fW", cdp_get_number(ndo, tptr, len) / 1000.0);
break;
- case 0x11: /* MTU - not documented */
- printf("%u bytes", EXTRACT_32BITS(tptr));
+ case 0x11: /* MTU - not documented */
+ if (len < 4)
+ goto trunc;
+ ND_PRINT("%u bytes", GET_BE_U_4(tptr));
break;
- case 0x12: /* AVVID trust bitmap - not documented */
- printf("0x%02x", *(tptr) );
+ case 0x12: /* AVVID trust bitmap - not documented */
+ if (len < 1)
+ goto trunc;
+ ND_PRINT("0x%02x", GET_U_1(tptr));
break;
- case 0x13: /* AVVID untrusted port CoS - not documented */
- printf("0x%02x", *(tptr));
+ case 0x13: /* AVVID untrusted port CoS - not documented */
+ if (len < 1)
+ goto trunc;
+ ND_PRINT("0x%02x", GET_U_1(tptr));
break;
- case 0x14: /* System Name - not documented */
- printf("'");
- fn_printn(tptr, len, NULL);
- printf("'");
+ case 0x14: /* System Name - not documented */
+ ND_PRINT("'");
+ (void)nd_printn(ndo, tptr, len, NULL);
+ ND_PRINT("'");
break;
- case 0x16: /* System Object ID - not documented */
- if (cdp_print_addr(tptr, len) < 0)
+ case 0x16: /* System Object ID - not documented */
+ if (cdp_print_addr(ndo, tptr, len) < 0)
goto trunc;
break;
- case 0x17: /* Physical Location - not documented */
- printf("0x%02x", *(tptr));
+ case 0x17: /* Physical Location - not documented */
+ if (len < 1)
+ goto trunc;
+ ND_PRINT("0x%02x", GET_U_1(tptr));
if (len > 1) {
- printf("/");
- fn_printn(tptr + 1, len - 1, NULL);
- }
+ ND_PRINT("/");
+ (void)nd_printn(ndo, tptr + 1, len - 1, NULL);
+ }
break;
- default:
- print_unknown_data(gndo,tptr,"\n\t ",len);
- break;
- }
- }
- /* avoid infinite loop */
- if (len == 0)
+ default:
+ print_unknown_data(ndo, tptr, "\n\t ", len);
break;
+ }
+ }
tptr = tptr+len;
}
- if (vflag < 1)
- printf(", length %u",caplen);
+ if (ndo->ndo_vflag < 1)
+ ND_PRINT(", length %u", caplen);
return;
trunc:
- printf("%s", tstr);
+ nd_print_trunc(ndo);
}
/*
#define PT_IEEE_802_2 2 /* IEEE 802.2 LLC header */
static int
-cdp_print_addr(const u_char * p, int l)
+cdp_print_addr(netdissect_options *ndo,
+ const u_char * p, u_int l)
{
- int pt, pl, al, num;
+ u_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
- TCHECK2(*p, 2);
- num = EXTRACT_32BITS(p);
+ ND_TCHECK_4(p);
+ if (p + 4 > endp)
+ goto trunc;
+ num = GET_BE_U_4(p);
p += 4;
- while (p < endp && num >= 0) {
- TCHECK2(*p, 2);
+ while (p < endp && num != 0) {
+ ND_TCHECK_2(p);
if (p + 2 > endp)
goto trunc;
- pt = p[0]; /* type of "protocol" field */
- pl = p[1]; /* length of "protocol" field */
+ pt = GET_U_1(p); /* type of "protocol" field */
+ pl = GET_U_1(p + 1); /* length of "protocol" field */
p += 2;
- TCHECK2(p[pl], 2);
+ ND_TCHECK_2(p + pl);
if (p + pl + 2 > endp)
goto trunc;
- al = EXTRACT_16BITS(&p[pl]); /* address length */
+ al = GET_BE_U_2(p + pl); /* address length */
- if (pt == PT_NLPID && pl == 1 && *p == NLPID_IP && al == 4) {
+ if (pt == PT_NLPID && pl == 1 && GET_U_1(p) == NLPID_IP &&
+ al == 4) {
/*
* IPv4: protocol type = NLPID, protocol length = 1
* (1-byte NLPID), protocol = 0xcc (NLPID for IPv4),
*/
p += 3;
- TCHECK2(*p, 4);
+ ND_TCHECK_4(p);
if (p + 4 > endp)
goto trunc;
- printf("IPv4 (%u) %s",
- num,
- ipaddr_string(p));
+ ND_PRINT("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) {
/*
* Ethertype, address length = 16
*/
p += 10;
- TCHECK2(*p, al);
+ ND_TCHECK_LEN(p, al);
if (p + al > endp)
goto trunc;
- printf("IPv6 (%u) %s",
- num,
- ip6addr_string(p));
+ ND_PRINT("IPv6 (%u) %s", num, ip6addr_string(ndo, p));
p += al;
}
-#endif
else {
/*
* Generic case: just print raw data
*/
- TCHECK2(*p, pl);
+ ND_TCHECK_LEN(p, pl);
if (p + pl > endp)
goto trunc;
- printf("pt=0x%02x, pl=%d, pb=", *(p - 2), pl);
- while (pl-- > 0)
- printf(" %02x", *p++);
- TCHECK2(*p, 2);
+ ND_PRINT("pt=0x%02x, pl=%u, pb=", GET_U_1((p - 2)),
+ pl);
+ while (pl != 0) {
+ ND_PRINT(" %02x", GET_U_1(p));
+ p++;
+ pl--;
+ }
+ ND_TCHECK_2(p);
if (p + 2 > endp)
goto trunc;
- al = (*p << 8) + *(p + 1);
- printf(", al=%d, a=", al);
+ ND_PRINT(", al=%u, a=", al);
p += 2;
- TCHECK2(*p, al);
+ ND_TCHECK_LEN(p, al);
if (p + al > endp)
goto trunc;
- while (al-- > 0)
- printf(" %02x", *p++);
+ while (al != 0) {
+ ND_PRINT(" %02x", GET_U_1(p));
+ p++;
+ al--;
+ }
}
num--;
if (num)
- printf(" ");
+ ND_PRINT(" ");
}
return 0;
static int
-cdp_print_prefixes(const u_char * p, int l)
+cdp_print_prefixes(netdissect_options *ndo,
+ const u_char * p, u_int l)
{
if (l % 5)
goto trunc;
- printf(" IPv4 Prefixes (%d):", l / 5);
+ ND_PRINT(" IPv4 Prefixes (%u):", l / 5);
while (l > 0) {
- printf(" %u.%u.%u.%u/%u", p[0], p[1], p[2], p[3], p[4]);
+ ND_PRINT(" %u.%u.%u.%u/%u",
+ GET_U_1(p), GET_U_1(p + 1), GET_U_1(p + 2),
+ GET_U_1(p + 3), GET_U_1(p + 4));
l -= 5;
p += 5;
}
}
/* read in a <n>-byte number, MSB first
- * (of course this can handle max sizeof(long))
+ * (of course this can handle max sizeof(int))
*/
-static unsigned long cdp_get_number(const u_char * p, int l)
+static unsigned int
+cdp_get_number(netdissect_options *ndo, const u_char * p, u_int l)
{
- unsigned long res=0;
+ unsigned int res=0;
while( l>0 )
{
- res = (res<<8) + *p;
+ res = (res<<8) + GET_U_1(p);
p++; l--;
}
return res;
projects / tcpdump / blobdiff