X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/37a4aa82a953cd13e4a6af0b75ceab287de555a3..87889ba67add1e8abd77fdaacbfd831ee9335bcc:/tcpdump.c

diff --git a/tcpdump.c b/tcpdump.c
index 8d615d74..d77b4bda 100644
--- a/tcpdump.c
+++ b/tcpdump.c
@@ -43,6 +43,17 @@ The Regents of the University of California.  All rights reserved.\n";
 #include "config.h"
 #endif
 
+/*
+ * Mac OS X may ship pcap.h from libpcap 0.6 with a libpcap based on
+ * 0.8.  That means it has pcap_findalldevs() but the header doesn't
+ * define pcap_if_t, meaning that we can't actually *use* pcap_findalldevs().
+ */
+#ifdef HAVE_PCAP_FINDALLDEVS
+#ifndef HAVE_PCAP_IF_T
+#undef HAVE_PCAP_FINDALLDEVS
+#endif
+#endif
+
 #include <tcpdump-stdinc.h>
 
 #ifdef WIN32
@@ -66,12 +77,10 @@ extern int SIZE_BUF;
 #else
 #include "getopt_long.h"
 #endif
-#include <pcap.h>
-#include <signal.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <limits.h>
+/* Capsicum-specific code requires macros from <net/bpf.h>, which will fail
+ * to compile if <pcap.h> has already been included; including the headers
+ * in the opposite order works fine.
+ */
 #ifdef HAVE_CAPSICUM
 #include <sys/capability.h>
 #include <sys/ioccom.h>
@@ -79,6 +88,12 @@ extern int SIZE_BUF;
 #include <fcntl.h>
 #include <libgen.h>
 #endif	/* HAVE_CAPSICUM */
+#include <pcap.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
 #ifndef WIN32
 #include <sys/wait.h>
 #include <sys/resource.h>
@@ -614,12 +629,6 @@ show_devices_and_exit (void)
 #define J_FLAG
 #endif /* PCAP_ERROR_TSTAMP_TYPE_NOTSUP */
 
-#ifdef HAVE_PCAP_FINDALLDEVS
-#ifndef HAVE_PCAP_IF_T
-#undef HAVE_PCAP_FINDALLDEVS
-#endif
-#endif
-
 #ifdef HAVE_PCAP_FINDALLDEVS
 #define D_FLAG	"D"
 #else
@@ -951,6 +960,13 @@ main(int argc, char **argv)
 	else
 		program_name = argv[0];
 
+	/*
+	 * On platforms where the CPU doesn't support unaligned loads,
+	 * force unaligned accesses to abort with SIGBUS, rather than
+	 * being fixed up (slowly) by the OS kernel; on those platforms,
+	 * misaligned accesses are bugs, and we want tcpdump to crash so
+	 * that the bugs are reported.
+	 */
 	if (abort_on_misalignment(ebuf, sizeof(ebuf)) < 0)
 		error("%s", ebuf);
 
@@ -2303,7 +2319,8 @@ print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
 	/*
 	 * Some printers want to check that they're not walking off the
 	 * end of the packet.
-	 * Rather than pass it all the way down, we set this global.
+	 * Rather than pass it all the way down, we set this member
+	 * of the netdissect_options structure.
 	 */
 	ndo->ndo_snapend = sp + h->caplen;
 
@@ -2313,6 +2330,11 @@ print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
                 hdrlen = (*print_info->p.printer)(h, sp);
         }
 
+	/*
+	 * Restore the original snapend, as a printer might have
+	 * changed it.
+	 */
+	ndo->ndo_snapend = sp + h->caplen;
 	if (ndo->ndo_Xflag) {
 		/*
 		 * Print the raw packet data in hex and ASCII.
@@ -2411,7 +2433,7 @@ print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
 static void
 ndo_default_print(netdissect_options *ndo, const u_char *bp, u_int length)
 {
-	hex_and_ascii_print(ndo, "\n\t", bp, length); /* pass on lf and identation string */
+	hex_and_ascii_print(ndo, "\n\t", bp, length); /* pass on lf and indentation string */
 }
 
 void