fad-win32.c revision 511eca30a483e912c274e1d8ba3a0f8f081e2227 
1/*
2 * Copyright (c) 2002 - 2005 NetGroup, Politecnico di Torino (Italy)
3 * Copyright (c) 2005 - 2006 CACE Technologies, Davis (California)
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the Politecnico di Torino, CACE Technologies
16 * nor the names of its contributors may be used to endorse or promote
17 * products derived from this software without specific prior written
18 * permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
23 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
24 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
25 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
26 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
30 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 *
32 */
33
34#ifndef lint
35static const char rcsid[] _U_ =
36    "@(#) $Header: /tcpdump/master/libpcap/fad-win32.c,v 1.15 2007-09-25 20:34:36 guy Exp $ (LBL)";
37#endif
38
39#ifdef HAVE_CONFIG_H
40#include "config.h"
41#endif
42
43#include <pcap.h>
44#include <pcap-int.h>
45#include <Packet32.h>
46
47#include <errno.h>
48
49/*
50 * Add an entry to the list of addresses for an interface.
51 * "curdev" is the entry for that interface.
52 */
53static int
54add_addr_to_list(pcap_if_t *curdev, struct sockaddr *addr,
55    struct sockaddr *netmask, struct sockaddr *broadaddr,
56    struct sockaddr *dstaddr, char *errbuf)
57{
58	pcap_addr_t *curaddr, *prevaddr, *nextaddr;
59
60	/*
61	 * Allocate the new entry and fill it in.
62	 */
63	curaddr = (pcap_addr_t*)malloc(sizeof(pcap_addr_t));
64	if (curaddr == NULL) {
65		(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
66		    "malloc: %s", pcap_strerror(errno));
67		return (-1);
68	}
69
70	curaddr->next = NULL;
71	if (addr != NULL) {
72		curaddr->addr = (struct sockaddr*)dup_sockaddr(addr, sizeof(struct sockaddr_storage));
73		if (curaddr->addr == NULL) {
74			(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
75			    "malloc: %s", pcap_strerror(errno));
76			free(curaddr);
77			return (-1);
78		}
79	} else
80		curaddr->addr = NULL;
81
82	if (netmask != NULL) {
83		curaddr->netmask = (struct sockaddr*)dup_sockaddr(netmask, sizeof(struct sockaddr_storage));
84		if (curaddr->netmask == NULL) {
85			(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
86			    "malloc: %s", pcap_strerror(errno));
87			free(curaddr);
88			return (-1);
89		}
90	} else
91		curaddr->netmask = NULL;
92
93	if (broadaddr != NULL) {
94		curaddr->broadaddr = (struct sockaddr*)dup_sockaddr(broadaddr, sizeof(struct sockaddr_storage));
95		if (curaddr->broadaddr == NULL) {
96			(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
97			    "malloc: %s", pcap_strerror(errno));
98			free(curaddr);
99			return (-1);
100		}
101	} else
102		curaddr->broadaddr = NULL;
103
104	if (dstaddr != NULL) {
105		curaddr->dstaddr = (struct sockaddr*)dup_sockaddr(dstaddr, sizeof(struct sockaddr_storage));
106		if (curaddr->dstaddr == NULL) {
107			(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
108			    "malloc: %s", pcap_strerror(errno));
109			free(curaddr);
110			return (-1);
111		}
112	} else
113		curaddr->dstaddr = NULL;
114
115	/*
116	 * Find the end of the list of addresses.
117	 */
118	for (prevaddr = curdev->addresses; prevaddr != NULL; prevaddr = nextaddr) {
119		nextaddr = prevaddr->next;
120		if (nextaddr == NULL) {
121			/*
122			 * This is the end of the list.
123			 */
124			break;
125		}
126	}
127
128	if (prevaddr == NULL) {
129		/*
130		 * The list was empty; this is the first member.
131		 */
132		curdev->addresses = curaddr;
133	} else {
134		/*
135		 * "prevaddr" is the last member of the list; append
136		 * this member to it.
137		 */
138		prevaddr->next = curaddr;
139	}
140
141	return (0);
142}
143
144
145static int
146pcap_add_if_win32(pcap_if_t **devlist, char *name, const char *desc,
147    char *errbuf)
148{
149	pcap_if_t *curdev;
150	npf_if_addr if_addrs[MAX_NETWORK_ADDRESSES];
151	LONG if_addr_size;
152	int res = 0;
153
154	if_addr_size = MAX_NETWORK_ADDRESSES;
155
156	/*
157	 * Add an entry for this interface, with no addresses.
158	 */
159	if (add_or_find_if(&curdev, devlist, name, 0, desc, errbuf) == -1) {
160		/*
161		 * Failure.
162		 */
163		return (-1);
164	}
165
166	/*
167	 * Get the list of addresses for the interface.
168	 */
169	if (!PacketGetNetInfoEx((void *)name, if_addrs, &if_addr_size)) {
170		/*
171		 * Failure.
172		 *
173		 * We don't return an error, because this can happen with
174		 * NdisWan interfaces, and we want to supply them even
175		 * if we can't supply their addresses.
176		 *
177		 * We return an entry with an empty address list.
178		 */
179		return (0);
180	}
181
182	/*
183	 * Now add the addresses.
184	 */
185	while (if_addr_size-- > 0) {
186		/*
187		 * "curdev" is an entry for this interface; add an entry for
188		 * this address to its list of addresses.
189		 */
190		if(curdev == NULL)
191			break;
192		res = add_addr_to_list(curdev,
193		    (struct sockaddr *)&if_addrs[if_addr_size].IPAddress,
194		    (struct sockaddr *)&if_addrs[if_addr_size].SubnetMask,
195		    (struct sockaddr *)&if_addrs[if_addr_size].Broadcast,
196		    NULL,
197			errbuf);
198		if (res == -1) {
199			/*
200			 * Failure.
201			 */
202			break;
203		}
204	}
205
206	return (res);
207}
208
209
210/*
211 * Get a list of all interfaces that are up and that we can open.
212 * Returns -1 on error, 0 otherwise.
213 * The list, as returned through "alldevsp", may be null if no interfaces
214 * were up and could be opened.
215 *
216 * Win32 implementation, based on WinPcap
217 */
218int
219pcap_findalldevs_interfaces(pcap_if_t **alldevsp, char *errbuf)
220{
221	pcap_if_t *devlist = NULL;
222	int ret = 0;
223	const char *desc;
224	char *AdaptersName;
225	ULONG NameLength;
226	char *name;
227
228	/*
229	 * Find out how big a buffer we need.
230	 *
231	 * This call should always return FALSE; if the error is
232	 * ERROR_INSUFFICIENT_BUFFER, NameLength will be set to
233	 * the size of the buffer we need, otherwise there's a
234	 * problem, and NameLength should be set to 0.
235	 *
236	 * It shouldn't require NameLength to be set, but,
237	 * at least as of WinPcap 4.1.3, it checks whether
238	 * NameLength is big enough before it checks for a
239	 * NULL buffer argument, so, while it'll still do
240	 * the right thing if NameLength is uninitialized and
241	 * whatever junk happens to be there is big enough
242	 * (because the pointer argument will be null), it's
243	 * still reading an uninitialized variable.
244	 */
245	NameLength = 0;
246	if (!PacketGetAdapterNames(NULL, &NameLength))
247	{
248		DWORD last_error = GetLastError();
249
250		if (last_error != ERROR_INSUFFICIENT_BUFFER)
251		{
252			snprintf(errbuf, PCAP_ERRBUF_SIZE,
253				"PacketGetAdapterNames: %s",
254				pcap_win32strerror());
255			return (-1);
256		}
257	}
258
259	if (NameLength > 0)
260		AdaptersName = (char*) malloc(NameLength);
261	else
262	{
263		*alldevsp = NULL;
264		return 0;
265	}
266	if (AdaptersName == NULL)
267	{
268		snprintf(errbuf, PCAP_ERRBUF_SIZE, "Cannot allocate enough memory to list the adapters.");
269		return (-1);
270	}
271
272	if (!PacketGetAdapterNames(AdaptersName, &NameLength)) {
273		snprintf(errbuf, PCAP_ERRBUF_SIZE,
274			"PacketGetAdapterNames: %s",
275			pcap_win32strerror());
276		free(AdaptersName);
277		return (-1);
278	}
279
280	/*
281	 * "PacketGetAdapterNames()" returned a list of
282	 * null-terminated ASCII interface name strings,
283	 * terminated by a null string, followed by a list
284	 * of null-terminated ASCII interface description
285	 * strings, terminated by a null string.
286	 * This means there are two ASCII nulls at the end
287	 * of the first list.
288	 *
289	 * Find the end of the first list; that's the
290	 * beginning of the second list.
291	 */
292	desc = &AdaptersName[0];
293	while (*desc != '\0' || *(desc + 1) != '\0')
294		desc++;
295
296	/*
297 	 * Found it - "desc" points to the first of the two
298	 * nulls at the end of the list of names, so the
299	 * first byte of the list of descriptions is two bytes
300	 * after it.
301	 */
302	desc += 2;
303
304	/*
305	 * Loop over the elements in the first list.
306	 */
307	name = &AdaptersName[0];
308	while (*name != '\0') {
309		/*
310		 * Add an entry for this interface.
311		 */
312		if (pcap_add_if_win32(&devlist, name, desc, errbuf) == -1) {
313			/*
314			 * Failure.
315			 */
316			ret = -1;
317			break;
318		}
319		name += strlen(name) + 1;
320		desc += strlen(desc) + 1;
321	}
322
323	if (ret != -1) {
324		/*
325		 * We haven't had any errors yet; do any platform-specific
326		 * operations to add devices.
327		 */
328		if (pcap_platform_finddevs(&devlist, errbuf) < 0)
329			ret = -1;
330	}
331
332	if (ret == -1) {
333		/*
334		 * We had an error; free the list we've been constructing.
335		 */
336		if (devlist != NULL) {
337			pcap_freealldevs(devlist);
338			devlist = NULL;
339		}
340	}
341
342	*alldevsp = devlist;
343	free(AdaptersName);
344	return (ret);
345}
346