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#include <sys/param.h>
12#if defined(__APPLE__) || defined(__GLIBC__) || defined(__FreeBSD_version)
13#include <net/bpf.h>
14#endif /* __APPLE__ */
15#include <pcap.h>
16
17#include <sys/ioctl.h>
18#ifdef __sun__
19#include <libdlpi.h>
20#else /* __sun__ */
21#include <sys/sysctl.h>
22#endif /* __sun__ */
23
24#include <net/ethernet.h>
25#include <net/if.h>
26#include <net/if_dl.h>
27#include <net/route.h>
28#include <netinet/in.h>
29
30#include "common.h"
31#include "eloop.h"
32#include "l2_packet.h"
33
34
35static const u8 pae_group_addr[ETH_ALEN] =
36{ 0x01, 0x80, 0xc2, 0x00, 0x00, 0x03 };
37
38struct l2_packet_data {
39	pcap_t *pcap;
40	char ifname[100];
41	u8 own_addr[ETH_ALEN];
42	void (*rx_callback)(void *ctx, const u8 *src_addr,
43			    const u8 *buf, size_t len);
44	void *rx_callback_ctx;
45	int l2_hdr; /* whether to include layer 2 (Ethernet) header data
46		     * buffers */
47};
48
49
50int l2_packet_get_own_addr(struct l2_packet_data *l2, u8 *addr)
51{
52	os_memcpy(addr, l2->own_addr, ETH_ALEN);
53	return 0;
54}
55
56
57int l2_packet_send(struct l2_packet_data *l2, const u8 *dst_addr, u16 proto,
58		   const u8 *buf, size_t len)
59{
60	if (!l2->l2_hdr) {
61		int ret;
62		struct l2_ethhdr *eth = os_malloc(sizeof(*eth) + len);
63		if (eth == NULL)
64			return -1;
65		os_memcpy(eth->h_dest, dst_addr, ETH_ALEN);
66		os_memcpy(eth->h_source, l2->own_addr, ETH_ALEN);
67		eth->h_proto = htons(proto);
68		os_memcpy(eth + 1, buf, len);
69		ret = pcap_inject(l2->pcap, (u8 *) eth, len + sizeof(*eth));
70		os_free(eth);
71		return ret;
72	} else
73		return pcap_inject(l2->pcap, buf, len);
74}
75
76
77static void l2_packet_receive(int sock, void *eloop_ctx, void *sock_ctx)
78{
79	struct l2_packet_data *l2 = eloop_ctx;
80	pcap_t *pcap = sock_ctx;
81	struct pcap_pkthdr *hdr;
82	const u_char *packet;
83	struct l2_ethhdr *ethhdr;
84	unsigned char *buf;
85	size_t len;
86
87	if (pcap_next_ex(pcap, &hdr, &packet) == -1) {
88		wpa_printf(MSG_ERROR, "Error reading packet, has device disappeared?");
89		packet = NULL;
90		eloop_terminate();
91	}
92
93	if (!l2->rx_callback || !packet || hdr->caplen < sizeof(*ethhdr))
94		return;
95
96	ethhdr = (struct l2_ethhdr *) packet;
97	if (l2->l2_hdr) {
98		buf = (unsigned char *) ethhdr;
99		len = hdr->caplen;
100	} else {
101		buf = (unsigned char *) (ethhdr + 1);
102		len = hdr->caplen - sizeof(*ethhdr);
103		/* handle 8021Q encapsulated frames */
104		if (ethhdr->h_proto == htons(ETH_P_8021Q)) {
105			buf += ETHER_VLAN_ENCAP_LEN;
106			len -= ETHER_VLAN_ENCAP_LEN;
107		}
108	}
109	l2->rx_callback(l2->rx_callback_ctx, ethhdr->h_source, buf, len);
110}
111
112
113static int l2_packet_init_libpcap(struct l2_packet_data *l2,
114				  unsigned short protocol)
115{
116	bpf_u_int32 pcap_maskp, pcap_netp;
117	char pcap_filter[200], pcap_err[PCAP_ERRBUF_SIZE];
118	struct bpf_program pcap_fp;
119
120	pcap_lookupnet(l2->ifname, &pcap_netp, &pcap_maskp, pcap_err);
121	l2->pcap = pcap_open_live(l2->ifname, 2500, 0, 10, pcap_err);
122	if (l2->pcap == NULL) {
123		fprintf(stderr, "pcap_open_live: %s\n", pcap_err);
124		fprintf(stderr, "ifname='%s'\n", l2->ifname);
125		return -1;
126	}
127	if (pcap_datalink(l2->pcap) != DLT_EN10MB &&
128	    pcap_set_datalink(l2->pcap, DLT_EN10MB) < 0) {
129		fprintf(stderr, "pcap_set_datalink(DLT_EN10MB): %s\n",
130			pcap_geterr(l2->pcap));
131		return -1;
132	}
133	os_snprintf(pcap_filter, sizeof(pcap_filter),
134		    "not ether src " MACSTR " and "
135		    "( ether dst " MACSTR " or ether dst " MACSTR " ) and "
136		    "( ether proto 0x%x or ( vlan 0 and ether proto 0x%x ) )",
137		    MAC2STR(l2->own_addr), /* do not receive own packets */
138		    MAC2STR(l2->own_addr), MAC2STR(pae_group_addr),
139		    protocol, protocol);
140	if (pcap_compile(l2->pcap, &pcap_fp, pcap_filter, 1, pcap_netp) < 0) {
141		fprintf(stderr, "pcap_compile: %s\n", pcap_geterr(l2->pcap));
142		return -1;
143	}
144
145	if (pcap_setfilter(l2->pcap, &pcap_fp) < 0) {
146		fprintf(stderr, "pcap_setfilter: %s\n", pcap_geterr(l2->pcap));
147		return -1;
148	}
149
150	pcap_freecode(&pcap_fp);
151#ifndef __sun__
152	/*
153	 * When libpcap uses BPF we must enable "immediate mode" to
154	 * receive frames right away; otherwise the system may
155	 * buffer them for us.
156	 */
157	{
158		unsigned int on = 1;
159		if (ioctl(pcap_fileno(l2->pcap), BIOCIMMEDIATE, &on) < 0) {
160			fprintf(stderr, "%s: cannot enable immediate mode on "
161				"interface %s: %s\n",
162				__func__, l2->ifname, strerror(errno));
163			/* XXX should we fail? */
164		}
165	}
166#endif /* __sun__ */
167
168	eloop_register_read_sock(pcap_get_selectable_fd(l2->pcap),
169				 l2_packet_receive, l2, l2->pcap);
170
171	return 0;
172}
173
174
175static int eth_get(const char *device, u8 ea[ETH_ALEN])
176{
177#ifdef __sun__
178	dlpi_handle_t dh;
179	u32 physaddrlen = DLPI_PHYSADDR_MAX;
180	u8 physaddr[DLPI_PHYSADDR_MAX];
181	int retval;
182
183	retval = dlpi_open(device, &dh, 0);
184	if (retval != DLPI_SUCCESS) {
185		wpa_printf(MSG_ERROR, "dlpi_open error: %s",
186			   dlpi_strerror(retval));
187		return -1;
188	}
189
190	retval = dlpi_get_physaddr(dh, DL_CURR_PHYS_ADDR, physaddr,
191				   &physaddrlen);
192	if (retval != DLPI_SUCCESS) {
193		wpa_printf(MSG_ERROR, "dlpi_get_physaddr error: %s",
194			   dlpi_strerror(retval));
195		dlpi_close(dh);
196		return -1;
197	}
198	os_memcpy(ea, physaddr, ETH_ALEN);
199	dlpi_close(dh);
200#else /* __sun__ */
201	struct if_msghdr *ifm;
202	struct sockaddr_dl *sdl;
203	u_char *p, *buf;
204	size_t len;
205	int mib[] = { CTL_NET, AF_ROUTE, 0, AF_LINK, NET_RT_IFLIST, 0 };
206
207	if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0)
208		return -1;
209	if ((buf = os_malloc(len)) == NULL)
210		return -1;
211	if (sysctl(mib, 6, buf, &len, NULL, 0) < 0) {
212		os_free(buf);
213		return -1;
214	}
215	for (p = buf; p < buf + len; p += ifm->ifm_msglen) {
216		ifm = (struct if_msghdr *)p;
217		sdl = (struct sockaddr_dl *)(ifm + 1);
218		if (ifm->ifm_type != RTM_IFINFO ||
219		    (ifm->ifm_addrs & RTA_IFP) == 0)
220			continue;
221		if (sdl->sdl_family != AF_LINK || sdl->sdl_nlen == 0 ||
222		    os_memcmp(sdl->sdl_data, device, sdl->sdl_nlen) != 0)
223			continue;
224		os_memcpy(ea, LLADDR(sdl), sdl->sdl_alen);
225		break;
226	}
227	os_free(buf);
228
229	if (p >= buf + len) {
230		errno = ESRCH;
231		return -1;
232	}
233#endif /* __sun__ */
234	return 0;
235}
236
237
238struct l2_packet_data * l2_packet_init(
239	const char *ifname, const u8 *own_addr, unsigned short protocol,
240	void (*rx_callback)(void *ctx, const u8 *src_addr,
241			    const u8 *buf, size_t len),
242	void *rx_callback_ctx, int l2_hdr)
243{
244	struct l2_packet_data *l2;
245
246	l2 = os_zalloc(sizeof(struct l2_packet_data));
247	if (l2 == NULL)
248		return NULL;
249	os_strlcpy(l2->ifname, ifname, sizeof(l2->ifname));
250	l2->rx_callback = rx_callback;
251	l2->rx_callback_ctx = rx_callback_ctx;
252	l2->l2_hdr = l2_hdr;
253
254	if (eth_get(l2->ifname, l2->own_addr) < 0) {
255		fprintf(stderr, "Failed to get link-level address for "
256			"interface '%s'.\n", l2->ifname);
257		os_free(l2);
258		return NULL;
259	}
260
261	if (l2_packet_init_libpcap(l2, protocol)) {
262		os_free(l2);
263		return NULL;
264	}
265
266	return l2;
267}
268
269
270struct l2_packet_data * l2_packet_init_bridge(
271	const char *br_ifname, const char *ifname, const u8 *own_addr,
272	unsigned short protocol,
273	void (*rx_callback)(void *ctx, const u8 *src_addr,
274			    const u8 *buf, size_t len),
275	void *rx_callback_ctx, int l2_hdr)
276{
277	return l2_packet_init(br_ifname, own_addr, protocol, rx_callback,
278			      rx_callback_ctx, l2_hdr);
279}
280
281
282void l2_packet_deinit(struct l2_packet_data *l2)
283{
284	if (l2 != NULL) {
285		if (l2->pcap) {
286			eloop_unregister_read_sock(
287				pcap_get_selectable_fd(l2->pcap));
288			pcap_close(l2->pcap);
289		}
290		os_free(l2);
291	}
292}
293
294
295int l2_packet_get_ip_addr(struct l2_packet_data *l2, char *buf, size_t len)
296{
297	pcap_if_t *devs, *dev;
298	struct pcap_addr *addr;
299	struct sockaddr_in *saddr;
300	int found = 0;
301	char err[PCAP_ERRBUF_SIZE + 1];
302
303	if (pcap_findalldevs(&devs, err) < 0) {
304		wpa_printf(MSG_DEBUG, "pcap_findalldevs: %s\n", err);
305		return -1;
306	}
307
308	for (dev = devs; dev && !found; dev = dev->next) {
309		if (os_strcmp(dev->name, l2->ifname) != 0)
310			continue;
311
312		addr = dev->addresses;
313		while (addr) {
314			saddr = (struct sockaddr_in *) addr->addr;
315			if (saddr && saddr->sin_family == AF_INET) {
316				os_strlcpy(buf, inet_ntoa(saddr->sin_addr),
317					   len);
318				found = 1;
319				break;
320			}
321			addr = addr->next;
322		}
323	}
324
325	pcap_freealldevs(devs);
326
327	return found ? 0 : -1;
328}
329
330
331void l2_packet_notify_auth_start(struct l2_packet_data *l2)
332{
333}
334
335
336int l2_packet_set_packet_filter(struct l2_packet_data *l2,
337				enum l2_packet_filter_type type)
338{
339	return -1;
340}
341