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 program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * Alternatively, this software may be distributed under the terms of BSD
11 * license.
12 *
13 * See README and COPYING for more details.
14 */
15
16#include "includes.h"
17#if defined(__APPLE__) || defined(__GLIBC__)
18#include <net/bpf.h>
19#endif /* __APPLE__ */
20#include <pcap.h>
21
22#include <sys/ioctl.h>
23#ifdef __sun__
24#include <libdlpi.h>
25#else /* __sun__ */
26#include <sys/sysctl.h>
27#endif /* __sun__ */
28
29#include <net/if.h>
30#include <net/if_dl.h>
31#include <net/route.h>
32#include <netinet/in.h>
33
34#include "common.h"
35#include "eloop.h"
36#include "l2_packet.h"
37
38
39static const u8 pae_group_addr[ETH_ALEN] =
40{ 0x01, 0x80, 0xc2, 0x00, 0x00, 0x03 };
41
42struct l2_packet_data {
43	pcap_t *pcap;
44	char ifname[100];
45	u8 own_addr[ETH_ALEN];
46	void (*rx_callback)(void *ctx, const u8 *src_addr,
47			    const u8 *buf, size_t len);
48	void *rx_callback_ctx;
49	int l2_hdr; /* whether to include layer 2 (Ethernet) header data
50		     * buffers */
51};
52
53
54int l2_packet_get_own_addr(struct l2_packet_data *l2, u8 *addr)
55{
56	os_memcpy(addr, l2->own_addr, ETH_ALEN);
57	return 0;
58}
59
60
61int l2_packet_send(struct l2_packet_data *l2, const u8 *dst_addr, u16 proto,
62		   const u8 *buf, size_t len)
63{
64	if (!l2->l2_hdr) {
65		int ret;
66		struct l2_ethhdr *eth = os_malloc(sizeof(*eth) + len);
67		if (eth == NULL)
68			return -1;
69		os_memcpy(eth->h_dest, dst_addr, ETH_ALEN);
70		os_memcpy(eth->h_source, l2->own_addr, ETH_ALEN);
71		eth->h_proto = htons(proto);
72		os_memcpy(eth + 1, buf, len);
73		ret = pcap_inject(l2->pcap, (u8 *) eth, len + sizeof(*eth));
74		os_free(eth);
75		return ret;
76	} else
77		return pcap_inject(l2->pcap, buf, len);
78}
79
80
81static void l2_packet_receive(int sock, void *eloop_ctx, void *sock_ctx)
82{
83	struct l2_packet_data *l2 = eloop_ctx;
84	pcap_t *pcap = sock_ctx;
85	struct pcap_pkthdr hdr;
86	const u_char *packet;
87	struct l2_ethhdr *ethhdr;
88	unsigned char *buf;
89	size_t len;
90
91	packet = pcap_next(pcap, &hdr);
92
93	if (packet == NULL || 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	}
104	l2->rx_callback(l2->rx_callback_ctx, ethhdr->h_source, buf, len);
105}
106
107
108static int l2_packet_init_libpcap(struct l2_packet_data *l2,
109				  unsigned short protocol)
110{
111	bpf_u_int32 pcap_maskp, pcap_netp;
112	char pcap_filter[200], pcap_err[PCAP_ERRBUF_SIZE];
113	struct bpf_program pcap_fp;
114
115	pcap_lookupnet(l2->ifname, &pcap_netp, &pcap_maskp, pcap_err);
116	l2->pcap = pcap_open_live(l2->ifname, 2500, 0, 10, pcap_err);
117	if (l2->pcap == NULL) {
118		fprintf(stderr, "pcap_open_live: %s\n", pcap_err);
119		fprintf(stderr, "ifname='%s'\n", l2->ifname);
120		return -1;
121	}
122	if (pcap_datalink(l2->pcap) != DLT_EN10MB &&
123	    pcap_set_datalink(l2->pcap, DLT_EN10MB) < 0) {
124		fprintf(stderr, "pcap_set_datalink(DLT_EN10MB): %s\n",
125			pcap_geterr(l2->pcap));
126		return -1;
127	}
128	os_snprintf(pcap_filter, sizeof(pcap_filter),
129		    "not ether src " MACSTR " and "
130		    "( ether dst " MACSTR " or ether dst " MACSTR " ) and "
131		    "ether proto 0x%x",
132		    MAC2STR(l2->own_addr), /* do not receive own packets */
133		    MAC2STR(l2->own_addr), MAC2STR(pae_group_addr),
134		    protocol);
135	if (pcap_compile(l2->pcap, &pcap_fp, pcap_filter, 1, pcap_netp) < 0) {
136		fprintf(stderr, "pcap_compile: %s\n", pcap_geterr(l2->pcap));
137		return -1;
138	}
139
140	if (pcap_setfilter(l2->pcap, &pcap_fp) < 0) {
141		fprintf(stderr, "pcap_setfilter: %s\n", pcap_geterr(l2->pcap));
142		return -1;
143	}
144
145	pcap_freecode(&pcap_fp);
146#ifndef __sun__
147	/*
148	 * When libpcap uses BPF we must enable "immediate mode" to
149	 * receive frames right away; otherwise the system may
150	 * buffer them for us.
151	 */
152	{
153		unsigned int on = 1;
154		if (ioctl(pcap_fileno(l2->pcap), BIOCIMMEDIATE, &on) < 0) {
155			fprintf(stderr, "%s: cannot enable immediate mode on "
156				"interface %s: %s\n",
157				__func__, l2->ifname, strerror(errno));
158			/* XXX should we fail? */
159		}
160	}
161#endif /* __sun__ */
162
163	eloop_register_read_sock(pcap_get_selectable_fd(l2->pcap),
164				 l2_packet_receive, l2, l2->pcap);
165
166	return 0;
167}
168
169
170static int eth_get(const char *device, u8 ea[ETH_ALEN])
171{
172#ifdef __sun__
173	dlpi_handle_t dh;
174	u32 physaddrlen = DLPI_PHYSADDR_MAX;
175	u8 physaddr[DLPI_PHYSADDR_MAX];
176	int retval;
177
178	retval = dlpi_open(device, &dh, 0);
179	if (retval != DLPI_SUCCESS) {
180		wpa_printf(MSG_ERROR, "dlpi_open error: %s",
181			   dlpi_strerror(retval));
182		return -1;
183	}
184
185	retval = dlpi_get_physaddr(dh, DL_CURR_PHYS_ADDR, physaddr,
186				   &physaddrlen);
187	if (retval != DLPI_SUCCESS) {
188		wpa_printf(MSG_ERROR, "dlpi_get_physaddr error: %s",
189			   dlpi_strerror(retval));
190		dlpi_close(dh);
191		return -1;
192	}
193	os_memcpy(ea, physaddr, ETH_ALEN);
194	dlpi_close(dh);
195#else /* __sun__ */
196	struct if_msghdr *ifm;
197	struct sockaddr_dl *sdl;
198	u_char *p, *buf;
199	size_t len;
200	int mib[] = { CTL_NET, AF_ROUTE, 0, AF_LINK, NET_RT_IFLIST, 0 };
201
202	if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0)
203		return -1;
204	if ((buf = os_malloc(len)) == NULL)
205		return -1;
206	if (sysctl(mib, 6, buf, &len, NULL, 0) < 0) {
207		os_free(buf);
208		return -1;
209	}
210	for (p = buf; p < buf + len; p += ifm->ifm_msglen) {
211		ifm = (struct if_msghdr *)p;
212		sdl = (struct sockaddr_dl *)(ifm + 1);
213		if (ifm->ifm_type != RTM_IFINFO ||
214		    (ifm->ifm_addrs & RTA_IFP) == 0)
215			continue;
216		if (sdl->sdl_family != AF_LINK || sdl->sdl_nlen == 0 ||
217		    os_memcmp(sdl->sdl_data, device, sdl->sdl_nlen) != 0)
218			continue;
219		os_memcpy(ea, LLADDR(sdl), sdl->sdl_alen);
220		break;
221	}
222	os_free(buf);
223
224	if (p >= buf + len) {
225		errno = ESRCH;
226		return -1;
227	}
228#endif /* __sun__ */
229	return 0;
230}
231
232
233struct l2_packet_data * l2_packet_init(
234	const char *ifname, const u8 *own_addr, unsigned short protocol,
235	void (*rx_callback)(void *ctx, const u8 *src_addr,
236			    const u8 *buf, size_t len),
237	void *rx_callback_ctx, int l2_hdr)
238{
239	struct l2_packet_data *l2;
240
241	l2 = os_zalloc(sizeof(struct l2_packet_data));
242	if (l2 == NULL)
243		return NULL;
244	os_strlcpy(l2->ifname, ifname, sizeof(l2->ifname));
245	l2->rx_callback = rx_callback;
246	l2->rx_callback_ctx = rx_callback_ctx;
247	l2->l2_hdr = l2_hdr;
248
249	if (eth_get(l2->ifname, l2->own_addr) < 0) {
250		fprintf(stderr, "Failed to get link-level address for "
251			"interface '%s'.\n", l2->ifname);
252		os_free(l2);
253		return NULL;
254	}
255
256	if (l2_packet_init_libpcap(l2, protocol)) {
257		os_free(l2);
258		return NULL;
259	}
260
261	return l2;
262}
263
264
265void l2_packet_deinit(struct l2_packet_data *l2)
266{
267	if (l2 != NULL) {
268		if (l2->pcap) {
269			eloop_unregister_read_sock(
270				pcap_get_selectable_fd(l2->pcap));
271			pcap_close(l2->pcap);
272		}
273		os_free(l2);
274	}
275}
276
277
278int l2_packet_get_ip_addr(struct l2_packet_data *l2, char *buf, size_t len)
279{
280	pcap_if_t *devs, *dev;
281	struct pcap_addr *addr;
282	struct sockaddr_in *saddr;
283	int found = 0;
284	char err[PCAP_ERRBUF_SIZE + 1];
285
286	if (pcap_findalldevs(&devs, err) < 0) {
287		wpa_printf(MSG_DEBUG, "pcap_findalldevs: %s\n", err);
288		return -1;
289	}
290
291	for (dev = devs; dev && !found; dev = dev->next) {
292		if (os_strcmp(dev->name, l2->ifname) != 0)
293			continue;
294
295		addr = dev->addresses;
296		while (addr) {
297			saddr = (struct sockaddr_in *) addr->addr;
298			if (saddr && saddr->sin_family == AF_INET) {
299				os_strlcpy(buf, inet_ntoa(saddr->sin_addr),
300					   len);
301				found = 1;
302				break;
303			}
304			addr = addr->next;
305		}
306	}
307
308	pcap_freealldevs(devs);
309
310	return found ? 0 : -1;
311}
312
313
314void l2_packet_notify_auth_start(struct l2_packet_data *l2)
315{
316}
317