Pointers into packet data should usually be pointers to unsigned 1-byte

[tcpdump] / print-null.c

diff --git a/print-null.c b/print-null.c
index b0cafe12943310754157b84ffe840091eb0ae6be..6de6d48908b2ac8635effbfc504e70bdd09be166 100644 (file)
--- a/print-null.c
+++ b/print-null.c
@@ -20,129 +20,169 @@
  */
 
 #ifndef lint
  */
 
 #ifndef lint

-static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-null.c,v 1.28 1999-11-21 09:36:58 fenner Exp $ (LBL)";
+static const char rcsid[] _U_ =
+    "@(#) $Header: /tcpdump/master/tcpdump/print-null.c,v 1.56 2005-07-07 01:22:19 guy Exp $ (LBL)";

 #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 <sys/socket.h>
-#include <sys/file.h>
-#include <sys/ioctl.h>
-
-#if __STDC__
-struct mbuf;
-struct rtentry;
-#endif
-#include <net/if.h>
-
-#include <netinet/in.h>
-#include <netinet/in_systm.h>
-#include <netinet/ip.h>
-#include <netinet/if_ether.h>
-#include <netinet/ip_var.h>
-#include <netinet/udp.h>
-#include <netinet/udp_var.h>
-#include <netinet/tcp.h>
+#include <tcpdump-stdinc.h>

 
 #include <pcap.h>
 #include <stdio.h>
 #include <string.h>
 
 
 #include <pcap.h>
 #include <stdio.h>
 #include <string.h>
 

-#ifdef INET6
-#include <netinet/ip6.h>
-#endif
-

 #include "interface.h"
 #include "addrtoname.h"
 
 #include "interface.h"
 #include "addrtoname.h"
 

-#ifndef AF_NS
-#define AF_NS          6               /* XEROX NS protocols */
+#include "ip.h"
+#ifdef INET6
+#include "ip6.h"

 #endif
 
 /*
 #endif
 
 /*

- * The DLT_NULL packet header is 4 bytes long. It contains a network
- * order 32 bit integer that specifies the family, e.g. AF_INET
+ * The DLT_NULL packet header is 4 bytes long. It contains a host-byte-order
+ * 32-bit integer that specifies the family, e.g. AF_INET.
+ *
+ * Note here that "host" refers to the host on which the packets were
+ * captured; that isn't necessarily *this* host.
+ *
+ * The OpenBSD DLT_LOOP packet header is the same, except that the integer
+ * is in network byte order.

  */
 #define        NULL_HDRLEN 4
 
  */
 #define        NULL_HDRLEN 4
 

-static void
-null_print(const u_char *p, const struct ip *ip, u_int length)
-{
-       u_int family;
-
-       memcpy((char *)&family, (char *)p, sizeof(family));
-
-       if (nflag) {
-               /* XXX just dump the header */
-               return;
-       }
-       switch (family) {
+/*
+ * BSD AF_ values.
+ *
+ * Unfortunately, the BSDs don't all use the same value for AF_INET6,
+ * so, because we want to be able to read captures from all of the BSDs,
+ * we check for all of them.
+ */
+#define BSD_AF_INET            2
+#define BSD_AF_NS              6               /* XEROX NS protocols */
+#define BSD_AF_ISO             7
+#define BSD_AF_APPLETALK       16
+#define BSD_AF_IPX             23
+#define BSD_AF_INET6_BSD       24      /* OpenBSD (and probably NetBSD), BSD/OS */
+#define BSD_AF_INET6_FREEBSD   28
+#define BSD_AF_INET6_DARWIN    30
+
+const struct tok bsd_af_values[] = {
+        { BSD_AF_INET, "IPv4" },
+        { BSD_AF_NS, "NS" },
+        { BSD_AF_ISO, "ISO" },
+        { BSD_AF_APPLETALK, "Appletalk" },
+        { BSD_AF_IPX, "IPX" },
+        { BSD_AF_INET6_BSD, "IPv6" },
+        { BSD_AF_INET6_FREEBSD, "IPv6" },
+        { BSD_AF_INET6_DARWIN, "IPv6" },
+        { 0, NULL}
+};

 
 

-       case AF_INET:
-               printf("ip: ");
-               break;

 
 

-#ifdef INET6
-       case AF_INET6:
-               printf("ip6: ");
-               break;
-#endif
-
-       case AF_NS:
-               printf("ns: ");
-               break;
+/*
+ * Byte-swap a 32-bit number.
+ * ("htonl()" or "ntohl()" won't work - we want to byte-swap even on
+ * big-endian platforms.)
+ */
+#define        SWAPLONG(y) \
+((((y)&0xff)<<24) | (((y)&0xff00)<<8) | (((y)&0xff0000)>>8) | (((y)>>24)&0xff))

 
 

-       default:
-               printf("AF %d: ", family);
-               break;
+static inline void
+null_hdr_print(u_int family, u_int length)
+{
+       if (!qflag) {
+               (void)printf("AF %s (%u)",
+                       tok2str(bsd_af_values,"Unknown",family),family);
+       } else {
+               (void)printf("%s",
+                       tok2str(bsd_af_values,"Unknown AF %u",family));

        }
        }

+
+       (void)printf(", length %u: ", length);

 }
 
 }
 

-void
-null_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
+/*
+ * This is the top level routine of the printer.  'p' points
+ * to the ether header of the packet, 'h->ts' is the timestamp,
+ * 'h->len' is the length of the packet off the wire, and 'h->caplen'
+ * is the number of bytes actually captured.
+ */
+u_int
+null_if_print(const struct pcap_pkthdr *h, const u_char *p)

 {
        u_int length = h->len;
        u_int caplen = h->caplen;
 {
        u_int length = h->len;
        u_int caplen = h->caplen;

-       const struct ip *ip;
+       u_int family;

 
 

-       ts_print(&h->ts);
+       if (caplen < NULL_HDRLEN) {
+               printf("[|null]");
+               return (NULL_HDRLEN);
+       }
+
+       memcpy((char *)&family, (char *)p, sizeof(family));

 
        /*
 
        /*

-        * Some printers want to get back at the link level addresses,
-        * and/or check that they're not walking off the end of the packet.
-        * Rather than pass them all the way down, we set these globals.
+        * This isn't necessarily in our host byte order; if this is
+        * a DLT_LOOP capture, it's in network byte order, and if
+        * this is a DLT_NULL capture from a machine with the opposite
+        * byte-order, it's in the opposite byte order from ours.
+        *
+        * If the upper 16 bits aren't all zero, assume it's byte-swapped.

         */
         */

-       packetp = p;
-       snapend = p + caplen;
+       if ((family & 0xFFFF0000) != 0)
+               family = SWAPLONG(family);

 
 

-       length -= NULL_HDRLEN;
+       if (eflag)
+               null_hdr_print(family, length);

 
 

-       ip = (struct ip *)(p + NULL_HDRLEN);
+       length -= NULL_HDRLEN;
+       caplen -= NULL_HDRLEN;
+       p += NULL_HDRLEN;

 
 

-       if (eflag)
-               null_print(p, ip, length);
+       switch (family) {

 
 

-       switch (ip->ip_v) {
-       case 4 :
-               ip_print((const void *)ip, length);
+       case BSD_AF_INET:
+               ip_print(gndo, p, length);

                break;
                break;

+

 #ifdef INET6
 #ifdef INET6

-       case 6:
-               ipv6_print((const void *)ip, length);
+       case BSD_AF_INET6_BSD:
+       case BSD_AF_INET6_FREEBSD:
+       case BSD_AF_INET6_DARWIN:
+               ip6_print(p, length);

                break;
                break;

-#endif /* INET6 */
-       default :
-               printf("ip v%d", ip->ip_v);
+#endif
+
+       case BSD_AF_ISO:
+               isoclns_print(p, length, caplen);
+               break;
+
+       case BSD_AF_APPLETALK:
+               atalk_print(p, length);

                break;
                break;

+
+       case BSD_AF_IPX:
+               ipx_print(p, length);
+               break;
+
+       default:
+               /* unknown AF_ value */
+               if (!eflag)
+                       null_hdr_print(family, length + NULL_HDRLEN);
+               if (!suppress_default_print)
+                       default_print(p, caplen);

        }
 
        }
 

-       if (xflag)
-               default_print((const u_char *)ip, caplen - NULL_HDRLEN);
-       putchar('\n');
+       return (NULL_HDRLEN);

 }
 
 }
 

+/*
+ * Local Variables:
+ * c-style: whitesmith
+ * c-basic-offset: 8
+ * End:
+ */