Correctly check for various values of the ICMP type field.

[tcpdump] / print-cdp.c

diff --git a/print-cdp.c b/print-cdp.c
index 257f5131b52c2df7b4d7c9f3269dde5643634e2f..bef7f5eacadd701be847be9c2c5a6ff08d4289b6 100644 (file)
--- a/print-cdp.c
+++ b/print-cdp.c
@@ -25,175 +25,355 @@
  */
 
 #ifndef lint
  */
 
 #ifndef lint

-static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-cdp.c,v 1.6 2001-06-15 07:54:19 itojun Exp $";
+static const char rcsid[] _U_ =
+    "@(#) $Header: /tcpdump/master/tcpdump/print-cdp.c,v 1.25 2004-10-07 14:53:11 hannes Exp $";

 #endif
 
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
 #endif
 
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 

-#include <sys/param.h>
-#include <sys/time.h>
+#include <tcpdump-stdinc.h>

 
 

-#include <netinet/in.h>
-
-#include <ctype.h>
-#include <netdb.h>

 #include <stdio.h>
 #include <string.h>
 
 #include "interface.h"
 #include "addrtoname.h"
 #include "extract.h"                   /* must come after interface.h */
 #include <stdio.h>
 #include <string.h>
 
 #include "interface.h"
 #include "addrtoname.h"
 #include "extract.h"                   /* must come after interface.h */

+#include "nlpid.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 void cdp_print_addr(const u_char *, int);
-static void cdp_print_prefixes(const u_char *, int);
+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
 
 void

-cdp_print(const u_char *p, u_int length, u_int caplen,
-         const u_char *esrc, const u_char *edst)
+cdp_print(const u_char *pptr, u_int length, u_int caplen)

 {
 {

-       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;
        }
 
                (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("CDPv%u, ttl: %us", *tptr, *(tptr+1));
+        if (vflag)
+                printf(", checksum: %u (unverified), length %u", EXTRACT_16BITS(tptr), length);
+       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;
 
                        goto trunc;
 

-               switch (type) {
-               case 0x01:
-                       printf(" DevID '%.*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 ");
+                        printf("'");
+                        fn_printn(tptr, len, NULL);
+                        printf("'");

                        break;
                        break;

-               case 0x02:
-                       printf(" Addr");
-                       cdp_print_addr(p + i + 4, len - 4);
+                    case 0x02: /* Address */
+                        if (cdp_print_addr(tptr, len) < 0)
+                            goto trunc;

                        break;
                        break;

-               case 0x03:
-                       printf(" PortID '%.*s'", len - 4, p + i + 4);
+                    case 0x03: /* Port-ID */
+                        printf("'");
+                        fn_printn(tptr, len, NULL);
+                        printf("'");

                        break;
                        break;

-               case 0x04:
-                       printf(" CAP 0x%02x", (unsigned) p[i + 7]);
+                    case 0x04: /* Capabilities */
+                       printf("(0x%08x): %s",
+                               EXTRACT_32BITS(tptr),
+                               bittok2str(cdp_capability_values, "none",EXTRACT_32BITS(tptr)));

                        break;
                        break;

-               case 0x05:
-                       if (vflag > 1)
-                               printf(" Version:\n%.*s", len - 4, p + i + 4);
-                       else
-                               printf(" Version: (suppressed)");
+                    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;
                        break;

-               case 0x06:
-                       printf(" Platform: '%.*s'", len - 4, p + i + 4);
+                    case 0x06: /* Platform */
+                        printf("'");
+                        fn_printn(tptr, len, NULL);
+                        printf("'");

                        break;
                        break;

-               case 0x07:
-                       cdp_print_prefixes(p + i + 4, len - 4);
+                    case 0x07: /* Prefixes */
+                       if (cdp_print_prefixes(tptr, len) < 0)
+                            goto trunc;

                        break;
                        break;

-               case 0x09:              /* guess - not documented */
-                       printf(" VTP Management Domain: '%.*s'", len - 4,
-                           p + i + 4);
+                    case 0x08: /* Protocol Hello Option - not documented */

                        break;
                        break;

-               case 0x0a:              /* guess - not documented */
-                       printf(" Native VLAN ID: %d",
-                           (p[i + 4] << 8) + p[i + 4 + 1] - 1);
+                    case 0x09: /* VTP Mgmt Domain  - not documented */
+                        printf("'");
+                        fn_printn(tptr, len, NULL);
+                        printf("'");

                        break;
                        break;

-               case 0x0b:              /* guess - not documented */
-                       printf(" Duplex: %s", p[i + 4] ? "full": "half");
+                    case 0x0a: /* Native VLAN ID - not documented */
+                       printf("%d",EXTRACT_16BITS(tptr));

                        break;
                        break;

-               default:
-                       printf(" unknown field type %02x, len %d", type, len);
+                    case 0x0b: /* Duplex - not documented */
+                       printf("%s", *(tptr) ? "full": "half");

                        break;
                        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));
+                       break;
+                    case 0x10: /* ATA-186 VoIP VLAN assignment - incomplete doc. */
+                       printf("%1.2fW",
+                               cdp_get_number(tptr, len)/1000.0 );
+                       break;
+                    case 0x11: /* MTU - not documented */
+                       printf("%u bytes", EXTRACT_32BITS(tptr));
+                       break;
+                    case 0x12: /* AVVID trust bitmap - not documented */
+                       printf("0x%02x", *(tptr) );
+                       break;
+                    case 0x13: /* AVVID untrusted port CoS - not documented */
+                       printf("0x%02x", *(tptr));
+                       break;
+                    case 0x14: /* System Name - not documented */
+                        printf("'");
+                        fn_printn(tptr, len, NULL);
+                        printf("'");
+                       break;
+                    case 0x16: /* System Object ID - not documented */
+                       if (cdp_print_addr(tptr, len) < 0)
+                               goto trunc;
+                       break;
+                    case 0x17: /* Physical Location - not documented */
+                       printf("0x%02x", *(tptr));
+                       if (len > 1) {
+                               printf("/");
+                               fn_printn(tptr + 1, len - 1, NULL);
+                       }
+                       break;
+                    default:
+                        print_unknown_data(tptr,"\n\t  ",len);
+                       break;
+                    }
+                }

                /* avoid infinite loop */
                if (len == 0)
                        break;
                /* avoid infinite loop */
                if (len == 0)
                        break;

-               i += len;
+               tptr = tptr+len;

        }
        }

+        if (vflag < 1)
+            printf(", length %u",caplen);

 
        return;
 
        return;

-

 trunc:
        printf("[|cdp]");
 }
 
 trunc:
        printf("[|cdp]");
 }
 

-static void
+/*
+ * 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(const u_char * p, int l)
 {
 cdp_print_addr(const u_char * p, int l)
 {

-       int pl, al, num;
+       int pt, pl, al, num;

        const u_char *endp = p + l;
        const u_char *endp = p + l;

+#ifdef INET6
+       static u_char prot_ipv6[] = {
+               0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00, 0x86, 0xdd
+       };
+#endif

 
 

-       num = (p[0] << 24) + (p[1] << 16) + (p[2] << 8) + p[3];
+       TCHECK2(*p, 2);
+       num = EXTRACT_32BITS(p);

        p += 4;
 
        p += 4;
 

-       printf(" (%d): ", num);
-

        while (p < endp && num >= 0) {
        while (p < endp && num >= 0) {

-               if (p + 2 >= endp)
-                       break;
-               pl = p[1];
+               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;
 
                p += 2;
 

-               /* special case: IPv4, protocol type=0xcc, addr. length=4 */
-               if (p + 3 >= endp)
-                       break;
-               if (pl == 1 && *p == 0xcc && p[1] == 0 && p[2] == 4) {
-                       if (p + 7 >= endp)
-                               break;
+               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;
 
                        p += 3;
 

-                       printf("IPv4 %u.%u.%u.%u ", p[0], p[1], p[2], p[3]);
+                       TCHECK2(*p, 4);
+                       if (p + 4 > endp)
+                               goto trunc;
+                       printf("IPv4 (%u) %s",
+                               num,
+                               ipaddr_string(p));

                        p += 4;
                        p += 4;

-               } else {        /* generic case: just print raw data */
-                       if (p + pl >= endp)
-                               break;
-                       printf("pt=0x%02x, pl=%d, pb=", *(p-2), pl);
+               }
+#ifdef INET6
+               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;
+                       TCHECK2(*p, al);
+                       if (p + al > endp)
+                               goto trunc;
+
+                       printf("IPv6 (%u) %s",
+                               num,
+                               ip6addr_string(p));
+                       p += al;
+               }
+#endif
+               else {
+                       /*
+                        * Generic case: just print raw data
+                        */
+                       TCHECK2(*p, pl);
+                       if (p + pl > endp)
+                               goto trunc;
+                       printf("pt=0x%02x, pl=%d, pb=", *(p - 2), pl);

                        while (pl-- > 0)
                                printf(" %02x", *p++);
                        while (pl-- > 0)
                                printf(" %02x", *p++);

+                       TCHECK2(*p, 2);
+                       if (p + 2 > endp)
+                               goto trunc;

                        al = (*p << 8) + *(p + 1);
                        al = (*p << 8) + *(p + 1);

-                       if (p + 2 + al >= endp)
-                               break;

                        printf(", al=%d, a=", al);
                        p += 2;
                        printf(", al=%d, a=", al);
                        p += 2;

+                       TCHECK2(*p, al);
+                       if (p + al > endp)
+                               goto trunc;

                        while (al-- > 0)
                                printf(" %02x", *p++);
                }
                        while (al-- > 0)
                                printf(" %02x", *p++);
                }

-               printf("  ");

                num--;
                num--;

+               if (num)
+                       printf(" ");

        }
        }

+
+       return 0;
+
+trunc:
+       return -1;

 }
 
 
 }
 
 

-static void
+static int

 cdp_print_prefixes(const u_char * p, int l)
 {
 cdp_print_prefixes(const u_char * p, int l)
 {

+       if (l % 5)
+               goto trunc;
+

        printf(" IPv4 Prefixes (%d):", l / 5);
 
        while (l > 0) {
        printf(" IPv4 Prefixes (%d):", l / 5);
 
        while (l > 0) {

-               if (l < 5)
-                       break;

                printf(" %u.%u.%u.%u/%u", p[0], p[1], p[2], p[3], p[4]);
                l -= 5;
                p += 5;
        }
                printf(" %u.%u.%u.%u/%u", 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;

 }
 }