driver_nl80211.c

最新的Host AP 新添加了许多pcmcia 的驱动

/*
 * hostapd / Kernel driver communication via nl80211
 * Copyright (c) 2002-2007, Jouni Malinen <[e-mail]>
 * Copyright (c) 2003-2004, Instant802 Networks, Inc.
 * Copyright (c) 2005-2006, Devicescape Software, Inc.
 * Copyright (c) 2007, Johannes Berg <[e-mail]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Alternatively, this software may be distributed under the terms of BSD
 * license.
 *
 * See README and COPYING for more details.
 */

#include "includes.h"

#include <sys/ioctl.h>
#include <netlink/genl/genl.h>
#include <netlink/genl/family.h>
#include <netlink/genl/ctrl.h>
#include <netlink/msg.h>
#include <netlink/attr.h>
#include "nl80211_copy.h"
#include <net/if.h>
#include <netpacket/packet.h>
#include "wireless_copy.h"
#include <linux/filter.h>
#include <net/if_arp.h>

#include "hostapd.h"
#include "driver.h"
#include "ieee802_1x.h"
#include "eloop.h"
#include "ieee802_11.h"
#include "sta_info.h"
#include "hw_features.h"
#include "mlme.h"
#include "radiotap.h"
#include "radiotap_iter.h"

#ifdef CONFIG_LIBNL20
/* libnl 2.0 compatibility code */
#define nl_handle_alloc_cb nl_socket_alloc_cb
#define nl_handle_destroy nl_socket_free
#endif /* CONFIG_LIBNL20 */

enum ieee80211_msg_type {
	ieee80211_msg_normal = 0,
	ieee80211_msg_tx_callback_ack = 1,
	ieee80211_msg_tx_callback_fail = 2,
};

struct i802_driver_data {
	struct hostapd_data *hapd;

	char iface[IFNAMSIZ + 1];
	int bridge;
	int ioctl_sock; /* socket for ioctl() use */
	int wext_sock; /* socket for wireless events */
	int eapol_sock; /* socket for EAPOL frames */
	int monitor_sock; /* socket for monitor */
	int monitor_ifidx;

	int default_if_indices[16];
	int *if_indices;
	int num_if_indices;

	int we_version;
	struct nl_handle *nl_handle;
	struct nl_cache *nl_cache;
	struct nl_cb *nl_cb;
	struct genl_family *nl80211;
	int dtim_period, beacon_int;
	unsigned int beacon_set:1;
	unsigned int ieee802_1x_active:1;

	int last_freq;
	int last_freq_ht;
};


static void add_ifidx(struct i802_driver_data *drv, int ifidx)
{
	int i;
	int *old;

	for (i = 0; i < drv->num_if_indices; i++) {
		if (drv->if_indices[i] == 0) {
			drv->if_indices[i] = ifidx;
			return;
		}
	}

	if (drv->if_indices != drv->default_if_indices)
		old = drv->if_indices;
	else
		old = NULL;

	drv->if_indices = realloc(old,
				  sizeof(int) * (drv->num_if_indices + 1));
	if (!drv->if_indices) {
		if (!old)
			drv->if_indices = drv->default_if_indices;
		else
			drv->if_indices = old;
		wpa_printf(MSG_ERROR, "Failed to reallocate memory for "
			   "interfaces");
		wpa_printf(MSG_ERROR, "Ignoring EAPOL on interface %d", ifidx);
		return;
	}
	drv->if_indices[drv->num_if_indices] = ifidx;
	drv->num_if_indices++;
}


static void del_ifidx(struct i802_driver_data *drv, int ifidx)
{
	int i;

	for (i = 0; i < drv->num_if_indices; i++) {
		if (drv->if_indices[i] == ifidx) {
			drv->if_indices[i] = 0;
			break;
		}
	}
}


static int have_ifidx(struct i802_driver_data *drv, int ifidx)
{
	int i;

	if (ifidx == drv->bridge)
		return 1;

	for (i = 0; i < drv->num_if_indices; i++)
		if (drv->if_indices[i] == ifidx)
			return 1;

	return 0;
}


/* nl80211 code */
static int ack_handler(struct nl_msg *msg, void *arg)
{
	int *err = arg;
	*err = 0;
	return NL_STOP;
}

static int finish_handler(struct nl_msg *msg, void *arg)
{
	int *ret = arg;
	*ret = 0;
	return NL_SKIP;
}

static int error_handler(struct sockaddr_nl *nla, struct nlmsgerr *err,
			 void *arg)
{
	int *ret = arg;
	*ret = err->error;
	return NL_SKIP;
}

static int send_and_recv_msgs(struct i802_driver_data *drv,
			      struct nl_msg *msg,
			      int (*valid_handler)(struct nl_msg *, void *),
			      void *valid_data)
{
	struct nl_cb *cb;
	int err = -ENOMEM;

	cb = nl_cb_clone(drv->nl_cb);
	if (!cb)
		goto out;

	err = nl_send_auto_complete(drv->nl_handle, msg);
	if (err < 0)
		goto out;

	err = 1;

	nl_cb_err(cb, NL_CB_CUSTOM, error_handler, &err);
	nl_cb_set(cb, NL_CB_FINISH, NL_CB_CUSTOM, finish_handler, &err);
	nl_cb_set(cb, NL_CB_ACK, NL_CB_CUSTOM, ack_handler, &err);

	if (valid_handler)
		nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM,
			  valid_handler, valid_data);

	while (err > 0)
		nl_recvmsgs(drv->nl_handle, cb);
 out:
	nl_cb_put(cb);
	nlmsg_free(msg);
	return err;
}

static int hostapd_set_iface_flags(struct i802_driver_data *drv,
				   const char *ifname, int dev_up)
{
	struct ifreq ifr;

	if (drv->ioctl_sock < 0)
		return -1;

	memset(&ifr, 0, sizeof(ifr));
	os_strlcpy(ifr.ifr_name, ifname, IFNAMSIZ);

	if (ioctl(drv->ioctl_sock, SIOCGIFFLAGS, &ifr) != 0) {
		perror("ioctl[SIOCGIFFLAGS]");
		wpa_printf(MSG_DEBUG, "Could not read interface flags (%s)",
			   drv->iface);
		return -1;
	}

	if (dev_up)
		ifr.ifr_flags |= IFF_UP;
	else
		ifr.ifr_flags &= ~IFF_UP;

	if (ioctl(drv->ioctl_sock, SIOCSIFFLAGS, &ifr) != 0) {
		perror("ioctl[SIOCSIFFLAGS]");
		return -1;
	}

	return 0;
}


static int nl_set_encr(int ifindex, struct i802_driver_data *drv,
		       const char *alg, const u8 *addr, int idx, const u8 *key,
		       size_t key_len, int txkey)
{
	struct nl_msg *msg;
	int ret;

	msg = nlmsg_alloc();
	if (!msg)
		return -ENOMEM;

	if (strcmp(alg, "none") == 0) {
		genlmsg_put(msg, 0, 0, genl_family_get_id(drv->nl80211), 0,
			    0, NL80211_CMD_DEL_KEY, 0);
	} else {
		genlmsg_put(msg, 0, 0, genl_family_get_id(drv->nl80211), 0,
			    0, NL80211_CMD_NEW_KEY, 0);
		NLA_PUT(msg, NL80211_ATTR_KEY_DATA, key_len, key);
		if (strcmp(alg, "WEP") == 0) {
			if (key_len == 5)
				NLA_PUT_U32(msg, NL80211_ATTR_KEY_CIPHER,
					    0x000FAC01);
			else
				NLA_PUT_U32(msg, NL80211_ATTR_KEY_CIPHER,
					    0x000FAC05);
		} else if (strcmp(alg, "TKIP") == 0)
			NLA_PUT_U32(msg, NL80211_ATTR_KEY_CIPHER, 0x000FAC02);
		else if (strcmp(alg, "CCMP") == 0)
			NLA_PUT_U32(msg, NL80211_ATTR_KEY_CIPHER, 0x000FAC04);
		else if (strcmp(alg, "IGTK") == 0)
			NLA_PUT_U32(msg, NL80211_ATTR_KEY_CIPHER, 0x000FAC06);
		else {
			wpa_printf(MSG_ERROR, "%s: Unsupported encryption "
				   "algorithm '%s'", __func__, alg);
			nlmsg_free(msg);
			return -1;
		}
	}

	if (addr)
		NLA_PUT(msg, NL80211_ATTR_MAC, ETH_ALEN, addr);
	NLA_PUT_U8(msg, NL80211_ATTR_KEY_IDX, idx);
	NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, ifindex);

	ret = send_and_recv_msgs(drv, msg, NULL, NULL);
	if (ret == -ENOENT)
		ret = 0;

	/*
	 * If we failed or don't need to set the default TX key (below),
	 * we're done here.
	 */
	if (ret || !txkey || addr)
		return ret;

	msg = nlmsg_alloc();
	if (!msg)
		return -ENOMEM;

	genlmsg_put(msg, 0, 0, genl_family_get_id(drv->nl80211), 0,
		    0, NL80211_CMD_SET_KEY, 0);
	NLA_PUT_U8(msg, NL80211_ATTR_KEY_IDX, idx);
	NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, ifindex);
	if (strcmp(alg, "IGTK") == 0)
		NLA_PUT_FLAG(msg, NL80211_ATTR_KEY_DEFAULT_MGMT);
	else
		NLA_PUT_FLAG(msg, NL80211_ATTR_KEY_DEFAULT);

	ret = send_and_recv_msgs(drv, msg, NULL, NULL);
	if (ret == -ENOENT)
		ret = 0;
	return ret;
 nla_put_failure:
	return -ENOBUFS;
}


static int i802_set_encryption(const char *iface, void *priv, const char *alg,
			       const u8 *addr, int idx, const u8 *key,
			       size_t key_len, int txkey)
{
	struct i802_driver_data *drv = priv;
	int ret;

	ret = nl_set_encr(if_nametoindex(iface), drv, alg, addr, idx, key,
			  key_len, txkey);
	if (ret < 0)
		return ret;

	return ret;
}


static inline int min_int(int a, int b)
{
	if (a < b)
		return a;
	return b;
}


static int get_key_handler(struct nl_msg *msg, void *arg)
{
	struct nlattr *tb[NL80211_ATTR_MAX + 1];
	struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));

	nla_parse(tb, NL80211_ATTR_MAX, genlmsg_attrdata(gnlh, 0),
		  genlmsg_attrlen(gnlh, 0), NULL);

	/*
	 * TODO: validate the key index and mac address!
	 * Otherwise, there's a race condition as soon as
	 * the kernel starts sending key notifications.
	 */

	if (tb[NL80211_ATTR_KEY_SEQ])
		memcpy(arg, nla_data(tb[NL80211_ATTR_KEY_SEQ]),
		       min_int(nla_len(tb[NL80211_ATTR_KEY_SEQ]), 6));
	return NL_SKIP;
}


static int i802_get_seqnum(const char *iface, void *priv, const u8 *addr,
			   int idx, u8 *seq)
{
	struct i802_driver_data *drv = priv;
	struct nl_msg *msg;

	msg = nlmsg_alloc();
	if (!msg)
		return -ENOMEM;

	genlmsg_put(msg, 0, 0, genl_family_get_id(drv->nl80211), 0,
		    0, NL80211_CMD_GET_KEY, 0);

	if (addr)
		NLA_PUT(msg, NL80211_ATTR_MAC, ETH_ALEN, addr);
	NLA_PUT_U8(msg, NL80211_ATTR_KEY_IDX, idx);
	NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, if_nametoindex(iface));

	memset(seq, 0, 6);

	return send_and_recv_msgs(drv, msg, get_key_handler, seq);
 nla_put_failure:
	return -ENOBUFS;
}


static int i802_set_rate_sets(void *priv, int *supp_rates, int *basic_rates,
			      int mode)
{
	struct i802_driver_data *drv = priv;
	struct nl_msg *msg;
	u8 rates[NL80211_MAX_SUPP_RATES];
	u8 rates_len = 0;
	int i;

	msg = nlmsg_alloc();
	if (!msg)
		return -ENOMEM;

	genlmsg_put(msg, 0, 0, genl_family_get_id(drv->nl80211), 0, 0,
		    NL80211_CMD_SET_BSS, 0);

	for (i = 0; i < NL80211_MAX_SUPP_RATES && basic_rates[i] >= 0; i++)
		rates[rates_len++] = basic_rates[i] / 5;

	NLA_PUT(msg, NL80211_ATTR_BSS_BASIC_RATES, rates_len, rates);

	/* TODO: multi-BSS support */
	NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, if_nametoindex(drv->iface));

	return send_and_recv_msgs(drv, msg, NULL, NULL);
 nla_put_failure:
	return -ENOBUFS;
}


static int i802_send_frame(void *priv, const void *data, size_t len,
			   int encrypt, int flags)
{
	__u8 rtap_hdr[] = {
		0x00, 0x00, /* radiotap version */
		0x0e, 0x00, /* radiotap length */
		0x02, 0xc0, 0x00, 0x00, /* bmap: flags, tx and rx flags */
		IEEE80211_RADIOTAP_F_FRAG, /* F_FRAG (fragment if required) */
		0x00,       /* padding */
		0x00, 0x00, /* RX and TX flags to indicate that */
		0x00, 0x00, /* this is the injected frame directly */
	};
	struct i802_driver_data *drv = priv;
	struct iovec iov[2] = {
		{
			.iov_base = &rtap_hdr,
			.iov_len = sizeof(rtap_hdr),
		},
		{
			.iov_base = (void*)data,
			.iov_len = len,
		}
	};
	struct msghdr msg = {
		.msg_name = NULL,
		.msg_namelen = 0,
		.msg_iov = iov,
		.msg_iovlen = 2,
		.msg_control = NULL,
		.msg_controllen = 0,
		.msg_flags = 0,
	};

	if (encrypt)
		rtap_hdr[8] |= IEEE80211_RADIOTAP_F_WEP;

	return sendmsg(drv->monitor_sock, &msg, flags);
}

static int i802_send_mgmt_frame(void *priv, const void *data, size_t len,
				int flags)
{
	struct ieee80211_mgmt *mgmt;
	int do_not_encrypt = 0;
	u16 fc;

	mgmt = (struct ieee80211_mgmt *) data;
	fc = le_to_host16(mgmt->frame_control);

	if (WLAN_FC_GET_TYPE(fc) == WLAN_FC_TYPE_MGMT &&
	    WLAN_FC_GET_STYPE(fc) == WLAN_FC_STYPE_AUTH) {
		/*
		 * Only one of the authentication frame types is encrypted.
		 * In order for static WEP encryption to work properly (i.e.,
		 * to not encrypt the frame), we need to tell mac80211 about
		 * the frames that must not be encrypted.
		 */
		u16 auth_alg = le_to_host16(mgmt->u.auth.auth_alg);
		u16 auth_trans = le_to_host16(mgmt->u.auth.auth_transaction);
		if (auth_alg == WLAN_AUTH_OPEN ||
		    (auth_alg == WLAN_AUTH_SHARED_KEY && auth_trans != 3))
			do_not_encrypt = 1;
	}

	return i802_send_frame(priv, data, len, !do_not_encrypt, flags);
}

/* Set kernel driver on given frequency (MHz) */
static int i802_set_freq2(void *priv, struct hostapd_freq_params *freq)
{
	struct i802_driver_data *drv = priv;
	struct nl_msg *msg;

	msg = nlmsg_alloc();
	if (!msg)
		return -1;

	drv->last_freq = freq->freq;
	drv->last_freq_ht = freq->ht_enabled;

	genlmsg_put(msg, 0, 0, genl_family_get_id(drv->nl80211), 0, 0,
		    NL80211_CMD_SET_WIPHY, 0);

	NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, if_nametoindex(drv->iface));
	NLA_PUT_U32(msg, NL80211_ATTR_WIPHY_FREQ, freq->freq);
	if (freq->ht_enabled) {
		switch (freq->sec_channel_offset) {
		case -1:
			NLA_PUT_U32(msg, NL80211_ATTR_WIPHY_CHANNEL_TYPE,
				    NL80211_CHAN_HT40MINUS);
			break;
		case 1:
			NLA_PUT_U32(msg, NL80211_ATTR_WIPHY_CHANNEL_TYPE,
				    NL80211_CHAN_HT40PLUS);
			break;
		default:
			NLA_PUT_U32(msg, NL80211_ATTR_WIPHY_CHANNEL_TYPE,
				    NL80211_CHAN_HT20);
			break;
		}
	}

	if (send_and_recv_msgs(drv, msg, NULL, NULL) == 0)
		return 0;
 nla_put_failure:
	return -1;
}


static int i802_set_rts(void *priv, int rts)
{
	struct i802_driver_data *drv = priv;
	struct iwreq iwr;

	memset(&iwr, 0, sizeof(iwr));
	os_strlcpy(iwr.ifr_name, drv->hapd->conf->iface, IFNAMSIZ);
	iwr.u.rts.value = rts;
	iwr.u.rts.fixed = 1;

	if (ioctl(drv->ioctl_sock, SIOCSIWRTS, &iwr) < 0) {
		perror("ioctl[SIOCSIWRTS]");
		return -1;
	}

	return 0;
}