1/*
2 * WPA Supplicant - Layer2 packet handling with Linux packet sockets
3 * Copyright (c) 2003-2005, Jouni Malinen <j@w1.fi>
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9#include "includes.h"
10#include <sys/ioctl.h>
11#include <netpacket/packet.h>
12#include <net/if.h>
13
14#include "common.h"
15#include "eloop.h"
16#include "l2_packet.h"
17
18
19struct l2_packet_data {
20	int fd; /* packet socket for EAPOL frames */
21	char ifname[IFNAMSIZ + 1];
22	int ifindex;
23	u8 own_addr[ETH_ALEN];
24	void (*rx_callback)(void *ctx, const u8 *src_addr,
25			    const u8 *buf, size_t len);
26	void *rx_callback_ctx;
27	int l2_hdr; /* whether to include layer 2 (Ethernet) header data
28		     * buffers */
29};
30
31
32int l2_packet_get_own_addr(struct l2_packet_data *l2, u8 *addr)
33{
34	os_memcpy(addr, l2->own_addr, ETH_ALEN);
35	return 0;
36}
37
38
39int l2_packet_send(struct l2_packet_data *l2, const u8 *dst_addr, u16 proto,
40		   const u8 *buf, size_t len)
41{
42	int ret;
43	if (l2 == NULL)
44		return -1;
45	if (l2->l2_hdr) {
46		ret = send(l2->fd, buf, len, 0);
47		if (ret < 0)
48			wpa_printf(MSG_ERROR, "l2_packet_send - send: %s",
49				   strerror(errno));
50	} else {
51		struct sockaddr_ll ll;
52		os_memset(&ll, 0, sizeof(ll));
53		ll.sll_family = AF_PACKET;
54		ll.sll_ifindex = l2->ifindex;
55		ll.sll_protocol = htons(proto);
56		ll.sll_halen = ETH_ALEN;
57		os_memcpy(ll.sll_addr, dst_addr, ETH_ALEN);
58		ret = sendto(l2->fd, buf, len, 0, (struct sockaddr *) &ll,
59			     sizeof(ll));
60		if (ret < 0) {
61			wpa_printf(MSG_ERROR, "l2_packet_send - sendto: %s",
62				   strerror(errno));
63		}
64	}
65	return ret;
66}
67
68
69static void l2_packet_receive(int sock, void *eloop_ctx, void *sock_ctx)
70{
71	struct l2_packet_data *l2 = eloop_ctx;
72	u8 buf[2300];
73	int res;
74	struct sockaddr_ll ll;
75	socklen_t fromlen;
76
77	os_memset(&ll, 0, sizeof(ll));
78	fromlen = sizeof(ll);
79	res = recvfrom(sock, buf, sizeof(buf), 0, (struct sockaddr *) &ll,
80		       &fromlen);
81	if (res < 0) {
82		wpa_printf(MSG_DEBUG, "l2_packet_receive - recvfrom: %s",
83			   strerror(errno));
84		return;
85	}
86
87	l2->rx_callback(l2->rx_callback_ctx, ll.sll_addr, buf, res);
88}
89
90
91struct l2_packet_data * l2_packet_init(
92	const char *ifname, const u8 *own_addr, unsigned short protocol,
93	void (*rx_callback)(void *ctx, const u8 *src_addr,
94			    const u8 *buf, size_t len),
95	void *rx_callback_ctx, int l2_hdr)
96{
97	struct l2_packet_data *l2;
98	struct ifreq ifr;
99	struct sockaddr_ll ll;
100
101	l2 = os_zalloc(sizeof(struct l2_packet_data));
102	if (l2 == NULL)
103		return NULL;
104	os_strlcpy(l2->ifname, ifname, sizeof(l2->ifname));
105	l2->rx_callback = rx_callback;
106	l2->rx_callback_ctx = rx_callback_ctx;
107	l2->l2_hdr = l2_hdr;
108
109	l2->fd = socket(PF_PACKET, l2_hdr ? SOCK_RAW : SOCK_DGRAM,
110			htons(protocol));
111	if (l2->fd < 0) {
112		wpa_printf(MSG_ERROR, "%s: socket(PF_PACKET): %s",
113			   __func__, strerror(errno));
114		os_free(l2);
115		return NULL;
116	}
117	os_memset(&ifr, 0, sizeof(ifr));
118	os_strlcpy(ifr.ifr_name, l2->ifname, sizeof(ifr.ifr_name));
119	if (ioctl(l2->fd, SIOCGIFINDEX, &ifr) < 0) {
120		wpa_printf(MSG_ERROR, "%s: ioctl[SIOCGIFINDEX]: %s",
121			   __func__, strerror(errno));
122		close(l2->fd);
123		os_free(l2);
124		return NULL;
125	}
126	l2->ifindex = ifr.ifr_ifindex;
127
128	os_memset(&ll, 0, sizeof(ll));
129	ll.sll_family = PF_PACKET;
130	ll.sll_ifindex = ifr.ifr_ifindex;
131	ll.sll_protocol = htons(protocol);
132	if (bind(l2->fd, (struct sockaddr *) &ll, sizeof(ll)) < 0) {
133		wpa_printf(MSG_ERROR, "%s: bind[PF_PACKET]: %s",
134			   __func__, strerror(errno));
135		close(l2->fd);
136		os_free(l2);
137		return NULL;
138	}
139
140	if (ioctl(l2->fd, SIOCGIFHWADDR, &ifr) < 0) {
141		wpa_printf(MSG_ERROR, "%s: ioctl[SIOCGIFHWADDR]: %s",
142			   __func__, strerror(errno));
143		close(l2->fd);
144		os_free(l2);
145		return NULL;
146	}
147	os_memcpy(l2->own_addr, ifr.ifr_hwaddr.sa_data, ETH_ALEN);
148
149	eloop_register_read_sock(l2->fd, l2_packet_receive, l2, NULL);
150
151	return l2;
152}
153
154
155void l2_packet_deinit(struct l2_packet_data *l2)
156{
157	if (l2 == NULL)
158		return;
159
160	if (l2->fd >= 0) {
161		eloop_unregister_read_sock(l2->fd);
162		close(l2->fd);
163	}
164
165	os_free(l2);
166}
167
168
169int l2_packet_get_ip_addr(struct l2_packet_data *l2, char *buf, size_t len)
170{
171	int s;
172	struct ifreq ifr;
173	struct sockaddr_in *saddr;
174	size_t res;
175
176	s = socket(PF_INET, SOCK_DGRAM, 0);
177	if (s < 0) {
178		wpa_printf(MSG_ERROR, "%s: socket: %s",
179			   __func__, strerror(errno));
180		return -1;
181	}
182	os_memset(&ifr, 0, sizeof(ifr));
183	os_strlcpy(ifr.ifr_name, l2->ifname, sizeof(ifr.ifr_name));
184	if (ioctl(s, SIOCGIFADDR, &ifr) < 0) {
185		if (errno != EADDRNOTAVAIL)
186			wpa_printf(MSG_ERROR, "%s: ioctl[SIOCGIFADDR]: %s",
187				   __func__, strerror(errno));
188		close(s);
189		return -1;
190	}
191	close(s);
192	saddr = aliasing_hide_typecast(&ifr.ifr_addr, struct sockaddr_in);
193	if (saddr->sin_family != AF_INET)
194		return -1;
195	res = os_strlcpy(buf, inet_ntoa(saddr->sin_addr), len);
196	if (res >= len)
197		return -1;
198	return 0;
199}
200
201
202void l2_packet_notify_auth_start(struct l2_packet_data *l2)
203{
204}
205