]> The Tcpdump Group git mirrors - tcpdump/commitdiff
Use %u to print unsigned quantities.
authorguy <guy>
Fri, 27 Aug 2004 03:56:21 +0000 (03:56 +0000)
committerguy <guy>
Fri, 27 Aug 2004 03:56:21 +0000 (03:56 +0000)
Check, and use, the supplied packet length in the PPPoE dissector.  (It
reflects the actual packet length; snapend reflects the captured packet
length.)

As we're now doing bounds checks with TCHECK, the loop over the tagged
fields doesn't have to check against snapend.

print-ip.c
print-ip6.c
print-pppoe.c

index 8422f0d930efab2727948940cc77a8dc40e5bdc9..20b290c385e867f61212aa551a886d9ce6618703 100644 (file)
@@ -21,7 +21,7 @@
 
 #ifndef lint
 static const char rcsid[] _U_ =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-ip.c,v 1.128.2.7 2004-06-25 01:21:06 guy Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-ip.c,v 1.128.2.8 2004-08-27 03:56:21 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -396,7 +396,7 @@ ip_print(register const u_char *bp, register u_int length)
                return;
        }
        if (length < sizeof (struct ip)) {
-               (void)printf("truncated-ip %d", length);
+               (void)printf("truncated-ip %u", length);
                return;
        }
        hlen = IP_HL(ip) * 4;
index 3b72a77f2261fb774eccd33dcdb4e646c813db05..4e96228db79bdb71ff1802cee3a76d7deeb7557f 100644 (file)
@@ -21,7 +21,7 @@
 
 #ifndef lint
 static const char rcsid[] _U_ =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-ip6.c,v 1.32.2.8 2003-11-24 20:31:22 guy Exp $";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-ip6.c,v 1.32.2.9 2004-08-27 03:56:22 guy Exp $";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -63,14 +63,14 @@ ip6_print(register const u_char *bp, register u_int length)
 
        TCHECK(*ip6);
        if (length < sizeof (struct ip6_hdr)) {
-               (void)printf("truncated-ip6 %d", length);
+               (void)printf("truncated-ip6 %u", length);
                return;
        }
 
        payload_len = EXTRACT_16BITS(&ip6->ip6_plen);
        len = payload_len + sizeof(struct ip6_hdr);
        if (length < len)
-               (void)printf("truncated-ip6 - %d bytes missing!",
+               (void)printf("truncated-ip6 - %u bytes missing!",
                        len - length);
 
        /*
index 1479512290417662667b7b6292f14e1fb821c404..03886001aa8b3e0a11e374f1071b11b4692ba85a 100644 (file)
@@ -23,7 +23,7 @@
 
 #ifndef lint
 static const char rcsid[] _U_ =
-"@(#) $Header: /tcpdump/master/tcpdump/print-pppoe.c,v 1.24.2.5 2004-08-27 03:29:41 guy Exp $ (LBL)";
+"@(#) $Header: /tcpdump/master/tcpdump/print-pppoe.c,v 1.24.2.6 2004-08-27 03:56:22 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -101,9 +101,15 @@ pppoe_if_print(const struct pcap_pkthdr *h, register const u_char *p)
 u_int
 pppoe_print(register const u_char *bp, u_int length)
 {
-       u_short pppoe_ver, pppoe_type, pppoe_code, pppoe_sessionid, pppoe_length;
+       u_int16_t pppoe_ver, pppoe_type, pppoe_code, pppoe_sessionid;
+       u_int pppoe_length;
        const u_char *pppoe_packet, *pppoe_payload;
 
+       if (length < PPPOE_HDRLEN) {
+               (void)printf("truncated-pppoe %u", length);
+               return (length);
+       }
+       length -= PPPOE_HDRLEN;
        pppoe_packet = bp;
        TCHECK2(*pppoe_packet, PPPOE_HDRLEN);
        pppoe_ver  = (pppoe_packet[0] & 0xF0) >> 4;
@@ -113,11 +119,6 @@ pppoe_print(register const u_char *bp, u_int length)
        pppoe_length    = EXTRACT_16BITS(pppoe_packet + 4);
        pppoe_payload = pppoe_packet + PPPOE_HDRLEN;
 
-       if (snapend < pppoe_payload) {
-               printf(" truncated PPPoE");
-               return (PPPOE_HDRLEN);
-       }
-
        if (pppoe_ver != 1) {
                printf(" [ver %d]",pppoe_ver);
        }
@@ -127,25 +128,29 @@ pppoe_print(register const u_char *bp, u_int length)
 
        printf("PPPoE %s", tok2str(pppoecode2str, "PAD-%x", pppoe_code));
        if (pppoe_code == PPPOE_PADI && pppoe_length > 1484 - PPPOE_HDRLEN) {
-               printf(" [len %d!]",pppoe_length);
+               printf(" [len %u!]",pppoe_length);
+       }
+       if (pppoe_length > length) {
+               printf(" [len %u > %u!]", pppoe_length, length);
+               pppoe_length = length;
        }
        if (pppoe_sessionid) {
                printf(" [ses 0x%x]", pppoe_sessionid);
        }
 
-       if (pppoe_payload + pppoe_length < snapend && snapend-pppoe_payload+14 > 64) {
+       if (pppoe_length < length && length + ETHER_HDRLEN > 60) {
                /* (small packets are probably just padded up to the ethernet
-                  minimum of 64 bytes) */
-               printf(" [length %d (%d extra bytes)]",
-                   pppoe_length, snapend - pppoe_payload - pppoe_length);
+                  minimum of 60 bytes of data + 4 bytes of CRC) */
+               printf(" [length %u (%u extra bytes)]",
+                   pppoe_length, length - pppoe_length);
 #if RESPECT_PAYLOAD_LENGTH
-               snapend = pppoe_payload+pppoe_length;
+               if (snaplend > pppoe_payload+pppoe_length)
+                       snapend = pppoe_payload+pppoe_length;
 #else
                /* Actual PPPoE implementations appear to ignore the payload
                   length and use the full ethernet frame anyways */
-               pppoe_length = snapend-pppoe_payload;
+               pppoe_length = length;
 #endif
-               
        }
 
        if (pppoe_code) {
@@ -155,11 +160,10 @@ pppoe_print(register const u_char *bp, u_int length)
 
                /*
                 * loop invariant:
-                * p points to next tag,
+                * p points to current tag,
                 * tag_type is previous tag or 0xffff for first iteration
                 */
-               while (tag_type && p + 4 < pppoe_payload + length &&
-                   p + 4 < snapend) {
+               while (tag_type && p < pppoe_payload + pppoe_length) {
                        TCHECK2(*p, 4);
                        tag_type = EXTRACT_16BITS(p);
                        tag_len = EXTRACT_16BITS(p + 2);