1/*
2 * WPA Supplicant - Layer2 packet handling with FreeBSD
3 * Copyright (c) 2003-2005, Jouni Malinen <j@w1.fi>
4 * Copyright (c) 2005, Sam Leffler <sam@errno.com>
5 *
6 * This software may be distributed under the terms of the BSD license.
7 * See README for more details.
8 */
9
10#include "includes.h"
11#if defined(__APPLE__) || defined(__GLIBC__)
12#include <net/bpf.h>
13#endif /* __APPLE__ */
14#include <pcap.h>
15
16#include <sys/ioctl.h>
17#ifdef __sun__
18#include <libdlpi.h>
19#else /* __sun__ */
20#include <sys/sysctl.h>
21#endif /* __sun__ */
22
23#include <net/if.h>
24#include <net/if_dl.h>
25#include <net/route.h>
26#include <netinet/in.h>
27
28#include "common.h"
29#include "eloop.h"
30#include "l2_packet.h"
31
32
33static const u8 pae_group_addr[ETH_ALEN] =
34{ 0x01, 0x80, 0xc2, 0x00, 0x00, 0x03 };
35
36struct l2_packet_data {
37	pcap_t *pcap;
38	char ifname[100];
39	u8 own_addr[ETH_ALEN];
40	void (*rx_callback)(void *ctx, const u8 *src_addr,
41			    const u8 *buf, size_t len);
42	void *rx_callback_ctx;
43	int l2_hdr; /* whether to include layer 2 (Ethernet) header data
44		     * buffers */
45};
46
47
48int l2_packet_get_own_addr(struct l2_packet_data *l2, u8 *addr)
49{
50	os_memcpy(addr, l2->own_addr, ETH_ALEN);
51	return 0;
52}
53
54
55int l2_packet_send(struct l2_packet_data *l2, const u8 *dst_addr, u16 proto,
56		   const u8 *buf, size_t len)
57{
58	if (!l2->l2_hdr) {
59		int ret;
60		struct l2_ethhdr *eth = os_malloc(sizeof(*eth) + len);
61		if (eth == NULL)
62			return -1;
63		os_memcpy(eth->h_dest, dst_addr, ETH_ALEN);
64		os_memcpy(eth->h_source, l2->own_addr, ETH_ALEN);
65		eth->h_proto = htons(proto);
66		os_memcpy(eth + 1, buf, len);
67		ret = pcap_inject(l2->pcap, (u8 *) eth, len + sizeof(*eth));
68		os_free(eth);
69		return ret;
70	} else
71		return pcap_inject(l2->pcap, buf, len);
72}
73
74
75static void l2_packet_receive(int sock, void *eloop_ctx, void *sock_ctx)
76{
77	struct l2_packet_data *l2 = eloop_ctx;
78	pcap_t *pcap = sock_ctx;
79	struct pcap_pkthdr hdr;
80	const u_char *packet;
81	struct l2_ethhdr *ethhdr;
82	unsigned char *buf;
83	size_t len;
84
85	packet = pcap_next(pcap, &hdr);
86
87	if (packet == NULL || hdr.caplen < sizeof(*ethhdr))
88		return;
89
90	ethhdr = (struct l2_ethhdr *) packet;
91	if (l2->l2_hdr) {
92		buf = (unsigned char *) ethhdr;
93		len = hdr.caplen;
94	} else {
95		buf = (unsigned char *) (ethhdr + 1);
96		len = hdr.caplen - sizeof(*ethhdr);
97	}
98	l2->rx_callback(l2->rx_callback_ctx, ethhdr->h_source, buf, len);
99}
100
101
102static int l2_packet_init_libpcap(struct l2_packet_data *l2,
103				  unsigned short protocol)
104{
105	bpf_u_int32 pcap_maskp, pcap_netp;
106	char pcap_filter[200], pcap_err[PCAP_ERRBUF_SIZE];
107	struct bpf_program pcap_fp;
108
109	pcap_lookupnet(l2->ifname, &pcap_netp, &pcap_maskp, pcap_err);
110	l2->pcap = pcap_open_live(l2->ifname, 2500, 0, 10, pcap_err);
111	if (l2->pcap == NULL) {
112		fprintf(stderr, "pcap_open_live: %s\n", pcap_err);
113		fprintf(stderr, "ifname='%s'\n", l2->ifname);
114		return -1;
115	}
116	if (pcap_datalink(l2->pcap) != DLT_EN10MB &&
117	    pcap_set_datalink(l2->pcap, DLT_EN10MB) < 0) {
118		fprintf(stderr, "pcap_set_datalink(DLT_EN10MB): %s\n",
119			pcap_geterr(l2->pcap));
120		return -1;
121	}
122	os_snprintf(pcap_filter, sizeof(pcap_filter),
123		    "not ether src " MACSTR " and "
124		    "( ether dst " MACSTR " or ether dst " MACSTR " ) and "
125		    "ether proto 0x%x",
126		    MAC2STR(l2->own_addr), /* do not receive own packets */
127		    MAC2STR(l2->own_addr), MAC2STR(pae_group_addr),
128		    protocol);
129	if (pcap_compile(l2->pcap, &pcap_fp, pcap_filter, 1, pcap_netp) < 0) {
130		fprintf(stderr, "pcap_compile: %s\n", pcap_geterr(l2->pcap));
131		return -1;
132	}
133
134	if (pcap_setfilter(l2->pcap, &pcap_fp) < 0) {
135		fprintf(stderr, "pcap_setfilter: %s\n", pcap_geterr(l2->pcap));
136		return -1;
137	}
138
139	pcap_freecode(&pcap_fp);
140#ifndef __sun__
141	/*
142	 * When libpcap uses BPF we must enable "immediate mode" to
143	 * receive frames right away; otherwise the system may
144	 * buffer them for us.
145	 */
146	{
147		unsigned int on = 1;
148		if (ioctl(pcap_fileno(l2->pcap), BIOCIMMEDIATE, &on) < 0) {
149			fprintf(stderr, "%s: cannot enable immediate mode on "
150				"interface %s: %s\n",
151				__func__, l2->ifname, strerror(errno));
152			/* XXX should we fail? */
153		}
154	}
155#endif /* __sun__ */
156
157	eloop_register_read_sock(pcap_get_selectable_fd(l2->pcap),
158				 l2_packet_receive, l2, l2->pcap);
159
160	return 0;
161}
162
163
164static int eth_get(const char *device, u8 ea[ETH_ALEN])
165{
166#ifdef __sun__
167	dlpi_handle_t dh;
168	u32 physaddrlen = DLPI_PHYSADDR_MAX;
169	u8 physaddr[DLPI_PHYSADDR_MAX];
170	int retval;
171
172	retval = dlpi_open(device, &dh, 0);
173	if (retval != DLPI_SUCCESS) {
174		wpa_printf(MSG_ERROR, "dlpi_open error: %s",
175			   dlpi_strerror(retval));
176		return -1;
177	}
178
179	retval = dlpi_get_physaddr(dh, DL_CURR_PHYS_ADDR, physaddr,
180				   &physaddrlen);
181	if (retval != DLPI_SUCCESS) {
182		wpa_printf(MSG_ERROR, "dlpi_get_physaddr error: %s",
183			   dlpi_strerror(retval));
184		dlpi_close(dh);
185		return -1;
186	}
187	os_memcpy(ea, physaddr, ETH_ALEN);
188	dlpi_close(dh);
189#else /* __sun__ */
190	struct if_msghdr *ifm;
191	struct sockaddr_dl *sdl;
192	u_char *p, *buf;
193	size_t len;
194	int mib[] = { CTL_NET, AF_ROUTE, 0, AF_LINK, NET_RT_IFLIST, 0 };
195
196	if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0)
197		return -1;
198	if ((buf = os_malloc(len)) == NULL)
199		return -1;
200	if (sysctl(mib, 6, buf, &len, NULL, 0) < 0) {
201		os_free(buf);
202		return -1;
203	}
204	for (p = buf; p < buf + len; p += ifm->ifm_msglen) {
205		ifm = (struct if_msghdr *)p;
206		sdl = (struct sockaddr_dl *)(ifm + 1);
207		if (ifm->ifm_type != RTM_IFINFO ||
208		    (ifm->ifm_addrs & RTA_IFP) == 0)
209			continue;
210		if (sdl->sdl_family != AF_LINK || sdl->sdl_nlen == 0 ||
211		    os_memcmp(sdl->sdl_data, device, sdl->sdl_nlen) != 0)
212			continue;
213		os_memcpy(ea, LLADDR(sdl), sdl->sdl_alen);
214		break;
215	}
216	os_free(buf);
217
218	if (p >= buf + len) {
219		errno = ESRCH;
220		return -1;
221	}
222#endif /* __sun__ */
223	return 0;
224}
225
226
227struct l2_packet_data * l2_packet_init(
228	const char *ifname, const u8 *own_addr, unsigned short protocol,
229	void (*rx_callback)(void *ctx, const u8 *src_addr,
230			    const u8 *buf, size_t len),
231	void *rx_callback_ctx, int l2_hdr)
232{
233	struct l2_packet_data *l2;
234
235	l2 = os_zalloc(sizeof(struct l2_packet_data));
236	if (l2 == NULL)
237		return NULL;
238	os_strlcpy(l2->ifname, ifname, sizeof(l2->ifname));
239	l2->rx_callback = rx_callback;
240	l2->rx_callback_ctx = rx_callback_ctx;
241	l2->l2_hdr = l2_hdr;
242
243	if (eth_get(l2->ifname, l2->own_addr) < 0) {
244		fprintf(stderr, "Failed to get link-level address for "
245			"interface '%s'.\n", l2->ifname);
246		os_free(l2);
247		return NULL;
248	}
249
250	if (l2_packet_init_libpcap(l2, protocol)) {
251		os_free(l2);
252		return NULL;
253	}
254
255	return l2;
256}
257
258
259void l2_packet_deinit(struct l2_packet_data *l2)
260{
261	if (l2 != NULL) {
262		if (l2->pcap) {
263			eloop_unregister_read_sock(
264				pcap_get_selectable_fd(l2->pcap));
265			pcap_close(l2->pcap);
266		}
267		os_free(l2);
268	}
269}
270
271
272int l2_packet_get_ip_addr(struct l2_packet_data *l2, char *buf, size_t len)
273{
274	pcap_if_t *devs, *dev;
275	struct pcap_addr *addr;
276	struct sockaddr_in *saddr;
277	int found = 0;
278	char err[PCAP_ERRBUF_SIZE + 1];
279
280	if (pcap_findalldevs(&devs, err) < 0) {
281		wpa_printf(MSG_DEBUG, "pcap_findalldevs: %s\n", err);
282		return -1;
283	}
284
285	for (dev = devs; dev && !found; dev = dev->next) {
286		if (os_strcmp(dev->name, l2->ifname) != 0)
287			continue;
288
289		addr = dev->addresses;
290		while (addr) {
291			saddr = (struct sockaddr_in *) addr->addr;
292			if (saddr && saddr->sin_family == AF_INET) {
293				os_strlcpy(buf, inet_ntoa(saddr->sin_addr),
294					   len);
295				found = 1;
296				break;
297			}
298			addr = addr->next;
299		}
300	}
301
302	pcap_freealldevs(devs);
303
304	return found ? 0 : -1;
305}
306
307
308void l2_packet_notify_auth_start(struct l2_packet_data *l2)
309{
310}
311