* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
+/* \summary: Domain Name System (DNS) printer */
+
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
-#include <tcpdump-stdinc.h>
+#include <netdissect-stdinc.h>
#include "nameser.h"
#include <string.h>
-#include "interface.h"
+#include "netdissect.h"
#include "addrtoname.h"
-#include "extract.h" /* must come after interface.h */
+#include "addrtostr.h"
+#include "extract.h"
static const char *ns_ops[] = {
"", " inv_q", " stat", " op3", " notify", " update", " op6", " op7",
register u_int i, l;
register const u_char *rp = NULL;
register int compress = 0;
- int chars_processed;
int elt;
- int data_size = ndo->ndo_snapend - bp;
+ u_int offset, max_offset;
if ((l = labellen(ndo, cp)) == (u_int)-1)
return(NULL);
if (!ND_TTEST2(*cp, 1))
return(NULL);
- chars_processed = 1;
+ max_offset = (u_int)(cp - bp);
if (((i = *cp++) & INDIR_MASK) != INDIR_MASK) {
compress = 0;
rp = cp + l;
}
if (!ND_TTEST2(*cp, 1))
return(NULL);
- cp = bp + (((i << 8) | *cp) & 0x3fff);
+ offset = (((i << 8) | *cp) & 0x3fff);
+ /*
+ * This must move backwards in the packet.
+ * No RFC explicitly says that, but BIND's
+ * name decompression code requires it,
+ * as a way of preventing infinite loops
+ * and other bad behavior, and it's probably
+ * what was intended (compress by pointing
+ * to domain name suffixes already seen in
+ * the packet).
+ */
+ if (offset >= max_offset) {
+ ND_PRINT((ndo, "<BAD PTR>"));
+ return(NULL);
+ }
+ max_offset = offset;
+ cp = bp + offset;
if ((l = labellen(ndo, cp)) == (u_int)-1)
return(NULL);
if (!ND_TTEST2(*cp, 1))
return(NULL);
i = *cp++;
- chars_processed++;
-
- /*
- * If we've looked at every character in
- * the message, this pointer will make
- * us look at some character again,
- * which means we're looping.
- */
- if (chars_processed >= data_size) {
- ND_PRINT((ndo, "<LOOP>"));
- return (NULL);
- }
continue;
}
if ((i & INDIR_MASK) == EDNS0_MASK) {
}
cp += l;
- chars_processed += l;
ND_PRINT((ndo, "."));
if ((l = labellen(ndo, cp)) == (u_int)-1)
return(NULL);
if (!ND_TTEST2(*cp, 1))
return(NULL);
i = *cp++;
- chars_processed++;
if (!compress)
rp += l + 1;
}
} else if (ndo->ndo_vflag > 2) {
/* print ttl */
ND_PRINT((ndo, " ["));
- relts_print(ndo, EXTRACT_32BITS(cp));
+ unsigned_relts_print(ndo, EXTRACT_32BITS(cp));
ND_PRINT((ndo, "]"));
cp += 4;
} else {
EXTRACT_16BITS(cp), EXTRACT_16BITS(cp + 2)));
break;
-#ifdef INET6
case T_AAAA:
{
- struct in6_addr addr;
char ntop_buf[INET6_ADDRSTRLEN];
if (!ND_TTEST2(*cp, sizeof(struct in6_addr)))
return(NULL);
- memcpy(&addr, cp, sizeof(struct in6_addr));
ND_PRINT((ndo, " %s",
- inet_ntop(AF_INET6, &addr, ntop_buf, sizeof(ntop_buf))));
+ addrtostr6(cp, ntop_buf, sizeof(ntop_buf))));
break;
}
memset(&a, 0, sizeof(a));
memcpy(&a.s6_addr[pbyte], cp + 1, sizeof(a) - pbyte);
ND_PRINT((ndo, " %u %s", pbit,
- inet_ntop(AF_INET6, &a, ntop_buf, sizeof(ntop_buf))));
+ addrtostr6(&a, ntop_buf, sizeof(ntop_buf))));
}
if (pbit > 0) {
ND_PRINT((ndo, " "));
}
break;
}
-#endif /*INET6*/
case T_OPT:
ND_PRINT((ndo, " UDPsize=%u", class));
register const u_char *cp;
uint16_t b2;
+ if(length < sizeof(*np)) {
+ ND_PRINT((ndo, "domain"));
+ ND_PRINT((ndo, " [length %u < %zu]", length, sizeof(*np)));
+ ND_PRINT((ndo, " (invalid)"));
+ return;
+ }
+
np = (const HEADER *)bp;
ND_TCHECK(*np);
/* get the byte-order right */