Use "pcap_findalldevs()" if present.

svn path=/trunk/; revision=8655

1 files changed, 202 insertions, 24 deletions

diff --git a/capture-wpcap.c b/capture-wpcap.c
index 98de62ab46..88f6cbfd15 100644
--- a/capture-wpcap.c
+++ b/capture-wpcap.c
@@ -1,13 +1,14 @@
 /* capture-wpcap.c
- * Try to load WinPcap DLL at run-time.
+ * WinPcap-specific interfaces for capturing.  We load WinPcap at run
+ * time, so that we only need one Ethereal binary and one Tethereal binary
+ * for Windows, regardless of whether WinPcap is installed or not.
  *
- * $Id: capture-wpcap.c,v 1.3 2002/08/28 21:00:05 jmayer Exp $
+ * $Id: capture-wpcap.c,v 1.4 2003/10/10 03:00:09 guy Exp $
  *
  * Ethereal - Network traffic analyzer
- * By Gerald Combs <gerald@zing.org>
+ * By Gerald Combs <gerald@ethereal.com>
  * Copyright 2001 Gerald Combs
  *
- *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
  * as published by the Free Software Foundation; either version 2
@@ -34,6 +35,9 @@
 #include <pcap.h>
 #endif
 
+#include "pcap-util.h"
+#include "pcap-util-int.h"
+
 /* XXX - yes, I know, I should move cppmagic.h to a generic location. */
 #include "tools/lemon/cppmagic.h"
 
@@ -41,7 +45,6 @@ gboolean has_wpcap = FALSE;
 
 #ifdef HAVE_LIBPCAP
 
-
 static char*   (*p_pcap_lookupdev) (char *);
 static void    (*p_pcap_close) (pcap_t *);
 static int     (*p_pcap_stats) (pcap_t *, struct pcap_stat *);
@@ -60,29 +63,31 @@ static int     (*p_pcap_loop) (pcap_t *, int, pcap_handler, guchar *);
 typedef struct {
 	const char	*name;
 	gpointer	*ptr;
+	gboolean	optional;
 } symbol_table_t;
 
-#define SYM(x)	STRINGIFY(x) , (gpointer) &CONCAT(p_,x)
+#define SYM(x, y)	{ STRINGIFY(x) , (gpointer) &CONCAT(p_,x), y }
 
 void
 load_wpcap(void)
 {
 
-	/* These are the symbols I need from Wpcap */
-	symbol_table_t	symbols[] = {
-		SYM(pcap_lookupdev),
-		SYM(pcap_close),
-		SYM(pcap_stats),
-		SYM(pcap_dispatch),
-		SYM(pcap_snapshot),
-		SYM(pcap_datalink),
-		SYM(pcap_setfilter),
-		SYM(pcap_geterr),
-		SYM(pcap_compile),
-		SYM(pcap_lookupnet),
-		SYM(pcap_open_live),
-		SYM(pcap_loop),
-		NULL, NULL
+	/* These are the symbols I need or want from Wpcap */
+	static const symbol_table_t	symbols[] = {
+		SYM(pcap_lookupdev, FALSE),
+		SYM(pcap_close, FALSE),
+		SYM(pcap_stats, FALSE),
+		SYM(pcap_dispatch, FALSE),
+		SYM(pcap_snapshot, FALSE),
+		SYM(pcap_datalink, FALSE),
+		SYM(pcap_setfilter, FALSE),
+		SYM(pcap_geterr, FALSE),
+		SYM(pcap_compile, FALSE),
+		SYM(pcap_lookupnet, FALSE),
+		SYM(pcap_open_live, FALSE),
+		SYM(pcap_loop, FALSE),
+		SYM(pcap_findalldevs, TRUE),
+		{ NULL, NULL, FALSE }
 	};
 
 	GModule		*wh; /* wpcap handle */
@@ -95,9 +100,20 @@ load_wpcap(void)
 	}
 
 	sym = symbols;
-	while (sym && sym->name) {
+	while (sym->name) {
 		if (!g_module_symbol(wh, sym->name, sym->ptr)) {
-			return;
+			if (sym->optional) {
+				/*
+				 * We don't care if it's missing; we just
+				 * don't use it.
+				 */
+				*sym->ptr = NULL;
+			} else {
+				/*
+				 * We require this symbol.
+				 */
+				return;
+			}
 		}
 		sym++;
 	}
@@ -193,6 +209,169 @@ pcap_loop(pcap_t *a, int b, pcap_handler c, guchar *d)
 	return p_pcap_loop(a, b, c, d);
 }
 
+#ifdef HAVE_PCAP_FINDALLDEVS
+int
+pcap_findalldevs(pcap_if_t **a, char *b)
+{
+	g_assert(has_wpcap && p_pcap_findalldevs != NULL)
+	return p_pcap_findalldevs(a, b);
+}
+#endif
+
+/*
+ * This will use "pcap_findalldevs()" if we have it, otherwise it'll
+ * fall back on "pcap_lookupdev()".
+ */
+GList *
+get_interface_list(int *err, char *err_str)
+{
+	GList  *il = NULL;
+	wchar_t *names;
+	char *win95names;
+	char ascii_name[MAX_WIN_IF_NAME_LEN + 1];
+	char ascii_desc[MAX_WIN_IF_NAME_LEN + 1];
+	int i, j;
+
+#ifdef HAVE_PCAP_FINDALLDEVS
+	if (p_pcap_findalldevs != NULL)
+		return get_interface_list_findalldevs(err, errstr);
+#endif
+
+	/*
+	 * In WinPcap, pcap_lookupdev is implemented by calling
+	 * PacketGetAdapterNames.  According to the documentation
+	 * I could find:
+	 *
+	 *	http://winpcap.polito.it/docs/man/html/Packet32_8c.html#a43
+	 *
+	 * this means that:
+	 *
+	 * On Windows OT (95, 98, Me), pcap_lookupdev returns a sequence
+	 * of bytes consisting of:
+	 *
+	 *	a sequence of null-terminated ASCII strings (i.e., each
+	 *	one is terminated by a single 0 byte), giving the names
+	 *	of the interfaces;
+	 *
+	 *	an empty ASCII string (i.e., a single 0 byte);
+	 *
+	 *	a sequence of null-terminated ASCII strings, giving the
+	 *	descriptions of the interfaces;
+	 *
+	 *	an empty ASCII string.
+	 *
+	 * On Windows NT (NT 4.0, W2K, WXP, W2K3, etc.), pcap_lookupdev
+	 * returns a sequence of bytes consisting of:
+	 *
+	 *	a sequence of null-terminated double-byte Unicode strings
+	 *	(i.e., each one consits of a sequence of double-byte
+	 *	characters, terminated by a double-byte 0), giving the
+	 *	names of the interfaces;
+	 *
+	 *	an empty Unicode string (i.e., a double 0 byte);
+	 *
+	 *	a sequence of null-terminated ASCII strings, giving the
+	 *	descriptions of the interfaces;
+	 *
+	 *	an empty ASCII string.
+	 *
+	 * The Nth string in the first sequence is the name of the Nth
+	 * adapter; the Nth string in the second sequence is the
+	 * description of the Nth adapter.
+	 */
+
+	names = (wchar_t *)pcap_lookupdev(err_str);
+	i = 0;
+
+	if (names) {
+		char* desc = 0;
+		int desc_pos = 0;
+
+		if (names[0]<256) {
+			/*
+			 * If names[0] is less than 256 it means the first
+			 * byte is 0.  This implies that we are using Unicode
+			 * characters.
+			 */
+			while (*(names+desc_pos) || *(names+desc_pos-1))
+				desc_pos++;
+			desc_pos++;	/* Step over the extra '\0' */
+			desc = (char*)(names + desc_pos); /* cast *after* addition */
+
+			while (names[i] != 0) {
+				/*
+				 * Copy the Unicode description to an ASCII
+				 * string.
+				 */
+				j = 0;
+				while (*desc != 0) {
+					if (j < MAX_WIN_IF_NAME_LEN)
+						ascii_desc[j++] = *desc;
+					desc++;
+				}
+				ascii_desc[j] = '\0';
+				desc++;
+
+				/*
+				 * Copy the Unicode name to an ASCII string.
+				 */
+				j = 0;
+				while (names[i] != 0) {
+					if (j < MAX_WIN_IF_NAME_LEN)
+					ascii_name[j++] = names[i++];
+				}
+				ascii_name[j] = '\0';
+				i++;
+				il = g_list_append(il,
+				    if_info_new(ascii_name, ascii_desc));
+			}
+		} else {
+			/*
+			 * Otherwise we are in Windows 95/98 and using ASCII
+			 * (8-bit) characters.
+			 */
+			win95names=(char *)names;
+			while (*(win95names+desc_pos) || *(win95names+desc_pos-1))
+				desc_pos++;
+			desc_pos++;	/* Step over the extra '\0' */
+			desc = win95names + desc_pos;
+
+			while (win95names[i] != '\0') {
+				/*
+				 * "&win95names[i]" points to the current
+				 * interface name, and "desc" points to
+				 * that interface's description.
+				 */
+				il = g_list_append(il,
+				    if_info_new(&win95names[i], desc));
+
+				/*
+				 * Skip to the next description.
+				 */
+				while (*desc != 0)
+					desc++;
+				desc++;
+
+				/*
+				 * Skip to the next name.
+				 */
+				while (win95names[i] != 0)
+					i++;
+				i++;
+			}
+		}
+	}
+
+	if (il == NULL) {
+		/*
+		 * No interfaces found.
+		 */
+		*err = NO_INTERFACES_FOUND;
+	}
+
+	return il;
+}
+
 #else /* HAVE_LIBPCAP */
 
 void
@@ -201,5 +380,4 @@ load_wpcap(void)
 	return;
 }
 
-
 #endif /* HAVE_LIBPCAP */