[deliverable/linux.git] / net / wireless / util.c

/*
 * Wireless utility functions
 *
 * Copyright 2007-2009	Johannes Berg <johannes@sipsolutions.net>
 */
#include <linux/bitops.h>
#include <linux/etherdevice.h>
#include <net/cfg80211.h>
#include <net/ip.h>
#include "core.h"

struct ieee80211_rate *
ieee80211_get_response_rate(struct ieee80211_supported_band *sband,
			    u32 basic_rates, int bitrate)
{
	struct ieee80211_rate *result = &sband->bitrates[0];
	int i;

	for (i = 0; i < sband->n_bitrates; i++) {
		if (!(basic_rates & BIT(i)))
			continue;
		if (sband->bitrates[i].bitrate > bitrate)
			continue;
		result = &sband->bitrates[i];
	}

	return result;
}
EXPORT_SYMBOL(ieee80211_get_response_rate);

int ieee80211_channel_to_frequency(int chan)
{
	if (chan < 14)
		return 2407 + chan * 5;

	if (chan == 14)
		return 2484;

	/* FIXME: 802.11j 17.3.8.3.2 */
	return (chan + 1000) * 5;
}
EXPORT_SYMBOL(ieee80211_channel_to_frequency);

int ieee80211_frequency_to_channel(int freq)
{
	if (freq == 2484)
		return 14;

	if (freq < 2484)
		return (freq - 2407) / 5;

	/* FIXME: 802.11j 17.3.8.3.2 */
	return freq/5 - 1000;
}
EXPORT_SYMBOL(ieee80211_frequency_to_channel);

struct ieee80211_channel *__ieee80211_get_channel(struct wiphy *wiphy,
						  int freq)
{
	enum ieee80211_band band;
	struct ieee80211_supported_band *sband;
	int i;

	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
		sband = wiphy->bands[band];

		if (!sband)
			continue;

		for (i = 0; i < sband->n_channels; i++) {
			if (sband->channels[i].center_freq == freq)
				return &sband->channels[i];
		}
	}

	return NULL;
}
EXPORT_SYMBOL(__ieee80211_get_channel);

static void set_mandatory_flags_band(struct ieee80211_supported_band *sband,
				     enum ieee80211_band band)
{
	int i, want;

	switch (band) {
	case IEEE80211_BAND_5GHZ:
		want = 3;
		for (i = 0; i < sband->n_bitrates; i++) {
			if (sband->bitrates[i].bitrate == 60 ||
			    sband->bitrates[i].bitrate == 120 ||
			    sband->bitrates[i].bitrate == 240) {
				sband->bitrates[i].flags |=
					IEEE80211_RATE_MANDATORY_A;
				want--;
			}
		}
		WARN_ON(want);
		break;
	case IEEE80211_BAND_2GHZ:
		want = 7;
		for (i = 0; i < sband->n_bitrates; i++) {
			if (sband->bitrates[i].bitrate == 10) {
				sband->bitrates[i].flags |=
					IEEE80211_RATE_MANDATORY_B |
					IEEE80211_RATE_MANDATORY_G;
				want--;
			}

			if (sband->bitrates[i].bitrate == 20 ||
			    sband->bitrates[i].bitrate == 55 ||
			    sband->bitrates[i].bitrate == 110 ||
			    sband->bitrates[i].bitrate == 60 ||
			    sband->bitrates[i].bitrate == 120 ||
			    sband->bitrates[i].bitrate == 240) {
				sband->bitrates[i].flags |=
					IEEE80211_RATE_MANDATORY_G;
				want--;
			}

			if (sband->bitrates[i].bitrate != 10 &&
			    sband->bitrates[i].bitrate != 20 &&
			    sband->bitrates[i].bitrate != 55 &&
			    sband->bitrates[i].bitrate != 110)
				sband->bitrates[i].flags |=
					IEEE80211_RATE_ERP_G;
		}
		WARN_ON(want != 0 && want != 3 && want != 6);
		break;
	case IEEE80211_NUM_BANDS:
		WARN_ON(1);
		break;
	}
}

void ieee80211_set_bitrate_flags(struct wiphy *wiphy)
{
	enum ieee80211_band band;

	for (band = 0; band < IEEE80211_NUM_BANDS; band++)
		if (wiphy->bands[band])
			set_mandatory_flags_band(wiphy->bands[band], band);
}

int cfg80211_validate_key_settings(struct key_params *params, int key_idx,
				   const u8 *mac_addr)
{
	if (key_idx > 5)
		return -EINVAL;

	/*
	 * Disallow pairwise keys with non-zero index unless it's WEP
	 * (because current deployments use pairwise WEP keys with
	 * non-zero indizes but 802.11i clearly specifies to use zero)
	 */
	if (mac_addr && key_idx &&
	    params->cipher != WLAN_CIPHER_SUITE_WEP40 &&
	    params->cipher != WLAN_CIPHER_SUITE_WEP104)
		return -EINVAL;

	/* TODO: add definitions for the lengths to linux/ieee80211.h */
	switch (params->cipher) {
	case WLAN_CIPHER_SUITE_WEP40:
		if (params->key_len != 5)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_TKIP:
		if (params->key_len != 32)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_CCMP:
		if (params->key_len != 16)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_WEP104:
		if (params->key_len != 13)
			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_AES_CMAC:
		if (params->key_len != 16)
			return -EINVAL;
		break;
	default:
		return -EINVAL;
	}

	if (params->seq) {
		switch (params->cipher) {
		case WLAN_CIPHER_SUITE_WEP40:
		case WLAN_CIPHER_SUITE_WEP104:
			/* These ciphers do not use key sequence */
			return -EINVAL;
		case WLAN_CIPHER_SUITE_TKIP:
		case WLAN_CIPHER_SUITE_CCMP:
		case WLAN_CIPHER_SUITE_AES_CMAC:
			if (params->seq_len != 6)
				return -EINVAL;
			break;
		}
	}

	return 0;
}

/* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
/* Ethernet-II snap header (RFC1042 for most EtherTypes) */
const unsigned char rfc1042_header[] __aligned(2) =
	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
EXPORT_SYMBOL(rfc1042_header);

/* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
const unsigned char bridge_tunnel_header[] __aligned(2) =
	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
EXPORT_SYMBOL(bridge_tunnel_header);

unsigned int ieee80211_hdrlen(__le16 fc)
{
	unsigned int hdrlen = 24;

	if (ieee80211_is_data(fc)) {
		if (ieee80211_has_a4(fc))
			hdrlen = 30;
		if (ieee80211_is_data_qos(fc))
			hdrlen += IEEE80211_QOS_CTL_LEN;
		goto out;
	}

	if (ieee80211_is_ctl(fc)) {
		/*
		 * ACK and CTS are 10 bytes, all others 16. To see how
		 * to get this condition consider
		 *   subtype mask:   0b0000000011110000 (0x00F0)
		 *   ACK subtype:    0b0000000011010000 (0x00D0)
		 *   CTS subtype:    0b0000000011000000 (0x00C0)
		 *   bits that matter:         ^^^      (0x00E0)
		 *   value of those: 0b0000000011000000 (0x00C0)
		 */
		if ((fc & cpu_to_le16(0x00E0)) == cpu_to_le16(0x00C0))
			hdrlen = 10;
		else
			hdrlen = 16;
	}
out:
	return hdrlen;
}
EXPORT_SYMBOL(ieee80211_hdrlen);

unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
{
	const struct ieee80211_hdr *hdr =
			(const struct ieee80211_hdr *)skb->data;
	unsigned int hdrlen;

	if (unlikely(skb->len < 10))
		return 0;
	hdrlen = ieee80211_hdrlen(hdr->frame_control);
	if (unlikely(hdrlen > skb->len))
		return 0;
	return hdrlen;
}
EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb);

int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr)
{
	int ae = meshhdr->flags & MESH_FLAGS_AE;
	/* 7.1.3.5a.2 */
	switch (ae) {
	case 0:
		return 6;
	case 1:
		return 12;
	case 2:
		return 18;
	case 3:
		return 24;
	default:
		return 6;
	}
}

int ieee80211_data_to_8023(struct sk_buff *skb, u8 *addr,
			   enum nl80211_iftype iftype)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
	u16 hdrlen, ethertype;
	u8 *payload;
	u8 dst[ETH_ALEN];
	u8 src[ETH_ALEN] __aligned(2);

	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
		return -1;

	hdrlen = ieee80211_hdrlen(hdr->frame_control);

	/* convert IEEE 802.11 header + possible LLC headers into Ethernet
	 * header
	 * IEEE 802.11 address fields:
	 * ToDS FromDS Addr1 Addr2 Addr3 Addr4
	 *   0     0   DA    SA    BSSID n/a
	 *   0     1   DA    BSSID SA    n/a
	 *   1     0   BSSID SA    DA    n/a
	 *   1     1   RA    TA    DA    SA
	 */
	memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
	memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);

	switch (hdr->frame_control &
		cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
	case cpu_to_le16(IEEE80211_FCTL_TODS):
		if (unlikely(iftype != NL80211_IFTYPE_AP &&
			     iftype != NL80211_IFTYPE_AP_VLAN))
			return -1;
		break;
	case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
		if (unlikely(iftype != NL80211_IFTYPE_WDS &&
			     iftype != NL80211_IFTYPE_MESH_POINT))
			return -1;
		if (iftype == NL80211_IFTYPE_MESH_POINT) {
			struct ieee80211s_hdr *meshdr =
				(struct ieee80211s_hdr *) (skb->data + hdrlen);
			hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
			if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
				memcpy(dst, meshdr->eaddr1, ETH_ALEN);
				memcpy(src, meshdr->eaddr2, ETH_ALEN);
			}
		}
		break;
	case cpu_to_le16(IEEE80211_FCTL_FROMDS):
		if (iftype != NL80211_IFTYPE_STATION ||
		    (is_multicast_ether_addr(dst) &&
		     !compare_ether_addr(src, addr)))
			return -1;
		break;
	case cpu_to_le16(0):
		if (iftype != NL80211_IFTYPE_ADHOC)
			return -1;
		break;
	}

	if (unlikely(skb->len - hdrlen < 8))
		return -1;

	payload = skb->data + hdrlen;
	ethertype = (payload[6] << 8) | payload[7];

	if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
		    ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
		   compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
		/* remove RFC1042 or Bridge-Tunnel encapsulation and
		 * replace EtherType */
		skb_pull(skb, hdrlen + 6);
		memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
		memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
	} else {
		struct ethhdr *ehdr;
		__be16 len;

		skb_pull(skb, hdrlen);
		len = htons(skb->len);
		ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
		memcpy(ehdr->h_dest, dst, ETH_ALEN);
		memcpy(ehdr->h_source, src, ETH_ALEN);
		ehdr->h_proto = len;
	}
	return 0;
}
EXPORT_SYMBOL(ieee80211_data_to_8023);

int ieee80211_data_from_8023(struct sk_buff *skb, u8 *addr,
			     enum nl80211_iftype iftype, u8 *bssid, bool qos)
{
	struct ieee80211_hdr hdr;
	u16 hdrlen, ethertype;
	__le16 fc;
	const u8 *encaps_data;
	int encaps_len, skip_header_bytes;
	int nh_pos, h_pos;
	int head_need;

	if (unlikely(skb->len < ETH_HLEN))
		return -EINVAL;

	nh_pos = skb_network_header(skb) - skb->data;
	h_pos = skb_transport_header(skb) - skb->data;

	/* convert Ethernet header to proper 802.11 header (based on
	 * operation mode) */
	ethertype = (skb->data[12] << 8) | skb->data[13];
	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);

	switch (iftype) {
	case NL80211_IFTYPE_AP:
	case NL80211_IFTYPE_AP_VLAN:
		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
		/* DA BSSID SA */
		memcpy(hdr.addr1, skb->data, ETH_ALEN);
		memcpy(hdr.addr2, addr, ETH_ALEN);
		memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
		hdrlen = 24;
		break;
	case NL80211_IFTYPE_STATION:
		fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
		/* BSSID SA DA */
		memcpy(hdr.addr1, bssid, ETH_ALEN);
		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
		memcpy(hdr.addr3, skb->data, ETH_ALEN);
		hdrlen = 24;
		break;
	case NL80211_IFTYPE_ADHOC:
		/* DA SA BSSID */
		memcpy(hdr.addr1, skb->data, ETH_ALEN);
		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
		memcpy(hdr.addr3, bssid, ETH_ALEN);
		hdrlen = 24;
		break;
	default:
		return -EOPNOTSUPP;
	}

	if (qos) {
		fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
		hdrlen += 2;
	}

	hdr.frame_control = fc;
	hdr.duration_id = 0;
	hdr.seq_ctrl = 0;

	skip_header_bytes = ETH_HLEN;
	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
		encaps_data = bridge_tunnel_header;
		encaps_len = sizeof(bridge_tunnel_header);
		skip_header_bytes -= 2;
	} else if (ethertype > 0x600) {
		encaps_data = rfc1042_header;
		encaps_len = sizeof(rfc1042_header);
		skip_header_bytes -= 2;
	} else {
		encaps_data = NULL;
		encaps_len = 0;
	}

	skb_pull(skb, skip_header_bytes);
	nh_pos -= skip_header_bytes;
	h_pos -= skip_header_bytes;

	head_need = hdrlen + encaps_len - skb_headroom(skb);

	if (head_need > 0 || skb_cloned(skb)) {
		head_need = max(head_need, 0);
		if (head_need)
			skb_orphan(skb);

		if (pskb_expand_head(skb, head_need, 0, GFP_ATOMIC)) {
			printk(KERN_ERR "failed to reallocate Tx buffer\n");
			return -ENOMEM;
		}
		skb->truesize += head_need;
	}

	if (encaps_data) {
		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
		nh_pos += encaps_len;
		h_pos += encaps_len;
	}

	memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);

	nh_pos += hdrlen;
	h_pos += hdrlen;

	/* Update skb pointers to various headers since this modified frame
	 * is going to go through Linux networking code that may potentially
	 * need things like pointer to IP header. */
	skb_set_mac_header(skb, 0);
	skb_set_network_header(skb, nh_pos);
	skb_set_transport_header(skb, h_pos);

	return 0;
}
EXPORT_SYMBOL(ieee80211_data_from_8023);

/* Given a data frame determine the 802.1p/1d tag to use. */
unsigned int cfg80211_classify8021d(struct sk_buff *skb)
{
	unsigned int dscp;

	/* skb->priority values from 256->263 are magic values to
	 * directly indicate a specific 802.1d priority.  This is used
	 * to allow 802.1d priority to be passed directly in from VLAN
	 * tags, etc.
	 */
	if (skb->priority >= 256 && skb->priority <= 263)
		return skb->priority - 256;

	switch (skb->protocol) {
	case htons(ETH_P_IP):
		dscp = ip_hdr(skb)->tos & 0xfc;
		break;
	default:
		return 0;
	}

	return dscp >> 5;
}
EXPORT_SYMBOL(cfg80211_classify8021d);
Commit	Line	Data
8318d78a JB	1	/*
	2	* Wireless utility functions
	3	*
d3236553	4	* Copyright 2007-2009 Johannes Berg <johannes@sipsolutions.net>
8318d78a	5	*/
d3236553	6	#include <linux/bitops.h>
e31a16d6	7	#include <linux/etherdevice.h>
d3236553	8	#include <net/cfg80211.h>
e31a16d6	9	#include <net/ip.h>
8318d78a JB	10	#include "core.h"
8318d78a JB	11
bd815252 JB	12	struct ieee80211_rate *
bd815252 JB	13	ieee80211_get_response_rate(struct ieee80211_supported_band *sband,
881d948c	14	u32 basic_rates, int bitrate)
bd815252 JB	15	{
	16	struct ieee80211_rate *result = &sband->bitrates[0];
	17	int i;
	18
	19	for (i = 0; i < sband->n_bitrates; i++) {
	20	if (!(basic_rates & BIT(i)))
	21	continue;
	22	if (sband->bitrates[i].bitrate > bitrate)
	23	continue;
	24	result = &sband->bitrates[i];
	25	}
	26
	27	return result;
	28	}
	29	EXPORT_SYMBOL(ieee80211_get_response_rate);
	30
8318d78a JB	31	int ieee80211_channel_to_frequency(int chan)
	32	{
	33	if (chan < 14)
	34	return 2407 + chan * 5;
	35
	36	if (chan == 14)
	37	return 2484;
	38
	39	/* FIXME: 802.11j 17.3.8.3.2 */
	40	return (chan + 1000) * 5;
	41	}
	42	EXPORT_SYMBOL(ieee80211_channel_to_frequency);
	43
	44	int ieee80211_frequency_to_channel(int freq)
	45	{
	46	if (freq == 2484)
	47	return 14;
	48
	49	if (freq < 2484)
	50	return (freq - 2407) / 5;
	51
	52	/* FIXME: 802.11j 17.3.8.3.2 */
	53	return freq/5 - 1000;
	54	}
	55	EXPORT_SYMBOL(ieee80211_frequency_to_channel);
	56
6c507cd0 JB	57	struct ieee80211_channel __ieee80211_get_channel(struct wiphy wiphy,
6c507cd0 JB	58	int freq)
906c730a JB	59	{
	60	enum ieee80211_band band;
	61	struct ieee80211_supported_band *sband;
	62	int i;
	63
	64	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
	65	sband = wiphy->bands[band];
	66
	67	if (!sband)
	68	continue;
	69
	70	for (i = 0; i < sband->n_channels; i++) {
	71	if (sband->channels[i].center_freq == freq)
	72	return &sband->channels[i];
	73	}
	74	}
	75
	76	return NULL;
	77	}
6c507cd0	78	EXPORT_SYMBOL(__ieee80211_get_channel);
906c730a	79
8318d78a JB	80	static void set_mandatory_flags_band(struct ieee80211_supported_band *sband,
	81	enum ieee80211_band band)
	82	{
	83	int i, want;
	84
	85	switch (band) {
	86	case IEEE80211_BAND_5GHZ:
	87	want = 3;
	88	for (i = 0; i < sband->n_bitrates; i++) {
	89	if (sband->bitrates[i].bitrate == 60 \|\|
	90	sband->bitrates[i].bitrate == 120 \|\|
	91	sband->bitrates[i].bitrate == 240) {
	92	sband->bitrates[i].flags \|=
	93	IEEE80211_RATE_MANDATORY_A;
	94	want--;
	95	}
	96	}
	97	WARN_ON(want);
	98	break;
	99	case IEEE80211_BAND_2GHZ:
	100	want = 7;
	101	for (i = 0; i < sband->n_bitrates; i++) {
	102	if (sband->bitrates[i].bitrate == 10) {
	103	sband->bitrates[i].flags \|=
	104	IEEE80211_RATE_MANDATORY_B \|
	105	IEEE80211_RATE_MANDATORY_G;
	106	want--;
	107	}
	108
	109	if (sband->bitrates[i].bitrate == 20 \|\|
	110	sband->bitrates[i].bitrate == 55 \|\|
	111	sband->bitrates[i].bitrate == 110 \|\|
	112	sband->bitrates[i].bitrate == 60 \|\|
	113	sband->bitrates[i].bitrate == 120 \|\|
	114	sband->bitrates[i].bitrate == 240) {
	115	sband->bitrates[i].flags \|=
	116	IEEE80211_RATE_MANDATORY_G;
	117	want--;
	118	}
	119
aac09fbf JB	120	if (sband->bitrates[i].bitrate != 10 &&
	121	sband->bitrates[i].bitrate != 20 &&
	122	sband->bitrates[i].bitrate != 55 &&
	123	sband->bitrates[i].bitrate != 110)
8318d78a JB	124	sband->bitrates[i].flags \|=
	125	IEEE80211_RATE_ERP_G;
	126	}
406f2388	127	WARN_ON(want != 0 && want != 3 && want != 6);
8318d78a JB	128	break;
	129	case IEEE80211_NUM_BANDS:
	130	WARN_ON(1);
	131	break;
	132	}
	133	}
	134
	135	void ieee80211_set_bitrate_flags(struct wiphy *wiphy)
	136	{
	137	enum ieee80211_band band;
	138
	139	for (band = 0; band < IEEE80211_NUM_BANDS; band++)
	140	if (wiphy->bands[band])
	141	set_mandatory_flags_band(wiphy->bands[band], band);
	142	}
08645126 JB	143
	144	int cfg80211_validate_key_settings(struct key_params *params, int key_idx,
	145	const u8 *mac_addr)
	146	{
	147	if (key_idx > 5)
	148	return -EINVAL;
	149
	150	/*
	151	* Disallow pairwise keys with non-zero index unless it's WEP
	152	* (because current deployments use pairwise WEP keys with
	153	* non-zero indizes but 802.11i clearly specifies to use zero)
	154	*/
	155	if (mac_addr && key_idx &&
	156	params->cipher != WLAN_CIPHER_SUITE_WEP40 &&
	157	params->cipher != WLAN_CIPHER_SUITE_WEP104)
	158	return -EINVAL;
	159
	160	/* TODO: add definitions for the lengths to linux/ieee80211.h */
	161	switch (params->cipher) {
	162	case WLAN_CIPHER_SUITE_WEP40:
	163	if (params->key_len != 5)
	164	return -EINVAL;
	165	break;
	166	case WLAN_CIPHER_SUITE_TKIP:
	167	if (params->key_len != 32)
	168	return -EINVAL;
	169	break;
	170	case WLAN_CIPHER_SUITE_CCMP:
	171	if (params->key_len != 16)
	172	return -EINVAL;
	173	break;
	174	case WLAN_CIPHER_SUITE_WEP104:
	175	if (params->key_len != 13)
	176	return -EINVAL;
	177	break;
	178	case WLAN_CIPHER_SUITE_AES_CMAC:
	179	if (params->key_len != 16)
	180	return -EINVAL;
	181	break;
	182	default:
	183	return -EINVAL;
	184	}
	185
9f26a952 JM	186	if (params->seq) {
	187	switch (params->cipher) {
	188	case WLAN_CIPHER_SUITE_WEP40:
	189	case WLAN_CIPHER_SUITE_WEP104:
	190	/* These ciphers do not use key sequence */
	191	return -EINVAL;
	192	case WLAN_CIPHER_SUITE_TKIP:
	193	case WLAN_CIPHER_SUITE_CCMP:
	194	case WLAN_CIPHER_SUITE_AES_CMAC:
	195	if (params->seq_len != 6)
	196	return -EINVAL;
	197	break;
	198	}
	199	}
	200
08645126 JB	201	return 0;
08645126 JB	202	}
e31a16d6 ZY	203
	204	/* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
	205	/* Ethernet-II snap header (RFC1042 for most EtherTypes) */
	206	const unsigned char rfc1042_header[] __aligned(2) =
	207	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
	208	EXPORT_SYMBOL(rfc1042_header);
	209
	210	/* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
	211	const unsigned char bridge_tunnel_header[] __aligned(2) =
	212	{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
	213	EXPORT_SYMBOL(bridge_tunnel_header);
	214
	215	unsigned int ieee80211_hdrlen(__le16 fc)
	216	{
	217	unsigned int hdrlen = 24;
	218
	219	if (ieee80211_is_data(fc)) {
	220	if (ieee80211_has_a4(fc))
	221	hdrlen = 30;
	222	if (ieee80211_is_data_qos(fc))
	223	hdrlen += IEEE80211_QOS_CTL_LEN;
	224	goto out;
	225	}
	226
	227	if (ieee80211_is_ctl(fc)) {
	228	/*
	229	* ACK and CTS are 10 bytes, all others 16. To see how
	230	* to get this condition consider
	231	* subtype mask: 0b0000000011110000 (0x00F0)
	232	* ACK subtype: 0b0000000011010000 (0x00D0)
	233	* CTS subtype: 0b0000000011000000 (0x00C0)
	234	* bits that matter: ^^^ (0x00E0)
	235	* value of those: 0b0000000011000000 (0x00C0)
	236	*/
	237	if ((fc & cpu_to_le16(0x00E0)) == cpu_to_le16(0x00C0))
	238	hdrlen = 10;
	239	else
	240	hdrlen = 16;
	241	}
	242	out:
	243	return hdrlen;
	244	}
	245	EXPORT_SYMBOL(ieee80211_hdrlen);
	246
	247	unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
	248	{
	249	const struct ieee80211_hdr *hdr =
	250	(const struct ieee80211_hdr *)skb->data;
	251	unsigned int hdrlen;
	252
	253	if (unlikely(skb->len < 10))
	254	return 0;
	255	hdrlen = ieee80211_hdrlen(hdr->frame_control);
	256	if (unlikely(hdrlen > skb->len))
	257	return 0;
	258	return hdrlen;
	259	}
	260	EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb);
	261
	262	int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr)
	263	{
	264	int ae = meshhdr->flags & MESH_FLAGS_AE;
	265	/* 7.1.3.5a.2 */
	266	switch (ae) {
267	case 0:
268	return 6;
269	case 1:
270	return 12;
271	case 2:
272	return 18;
273	case 3:
274	return 24;
275	default:
276	return 6;
277	}
278	}
279
280	int ieee80211_data_to_8023(struct sk_buff skb, u8 addr,
281	enum nl80211_iftype iftype)
282	{
283	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) skb->data;
284	u16 hdrlen, ethertype;
285	u8 *payload;
286	u8 dst[ETH_ALEN];
287	u8 src[ETH_ALEN] __aligned(2);
288
289	if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
290	return -1;
291
292	hdrlen = ieee80211_hdrlen(hdr->frame_control);
293
294	/* convert IEEE 802.11 header + possible LLC headers into Ethernet
295	* header
296	* IEEE 802.11 address fields:
297	* ToDS FromDS Addr1 Addr2 Addr3 Addr4
298	* 0 0 DA SA BSSID n/a
299	* 0 1 DA BSSID SA n/a
300	* 1 0 BSSID SA DA n/a
301	* 1 1 RA TA DA SA
302	*/
303	memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
304	memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);
305
306	switch (hdr->frame_control &
307	cpu_to_le16(IEEE80211_FCTL_TODS \| IEEE80211_FCTL_FROMDS)) {
308	case cpu_to_le16(IEEE80211_FCTL_TODS):
309	if (unlikely(iftype != NL80211_IFTYPE_AP &&
310	iftype != NL80211_IFTYPE_AP_VLAN))
311	return -1;
312	break;
313	case cpu_to_le16(IEEE80211_FCTL_TODS \| IEEE80211_FCTL_FROMDS):
314	if (unlikely(iftype != NL80211_IFTYPE_WDS &&
315	iftype != NL80211_IFTYPE_MESH_POINT))
316	return -1;
317	if (iftype == NL80211_IFTYPE_MESH_POINT) {
318	struct ieee80211s_hdr *meshdr =
319	(struct ieee80211s_hdr *) (skb->data + hdrlen);
320	hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
321	if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
322	memcpy(dst, meshdr->eaddr1, ETH_ALEN);
323	memcpy(src, meshdr->eaddr2, ETH_ALEN);
324	}
325	}
326	break;
327	case cpu_to_le16(IEEE80211_FCTL_FROMDS):
328	if (iftype != NL80211_IFTYPE_STATION \|\|
329	(is_multicast_ether_addr(dst) &&
330	!compare_ether_addr(src, addr)))
331	return -1;
332	break;
333	case cpu_to_le16(0):
334	if (iftype != NL80211_IFTYPE_ADHOC)
335	return -1;
336	break;
337	}
338
339	if (unlikely(skb->len - hdrlen < 8))
340	return -1;
341
342	payload = skb->data + hdrlen;
343	ethertype = (payload[6] << 8) \| payload[7];
344
345	if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
346	ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) \|\|
347	compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
348	/* remove RFC1042 or Bridge-Tunnel encapsulation and
349	* replace EtherType */
350	skb_pull(skb, hdrlen + 6);
351	memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
352	memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
353	} else {
354	struct ethhdr *ehdr;
355	__be16 len;
356
357	skb_pull(skb, hdrlen);
358	len = htons(skb->len);
359	ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
360	memcpy(ehdr->h_dest, dst, ETH_ALEN);
361	memcpy(ehdr->h_source, src, ETH_ALEN);
362	ehdr->h_proto = len;
363	}
364	return 0;
365	}
366	EXPORT_SYMBOL(ieee80211_data_to_8023);
367
368	int ieee80211_data_from_8023(struct sk_buff skb, u8 addr,
369	enum nl80211_iftype iftype, u8 *bssid, bool qos)
370	{
371	struct ieee80211_hdr hdr;
372	u16 hdrlen, ethertype;
373	__le16 fc;
374	const u8 *encaps_data;
375	int encaps_len, skip_header_bytes;
376	int nh_pos, h_pos;
377	int head_need;
378
379	if (unlikely(skb->len < ETH_HLEN))
380	return -EINVAL;
381
382	nh_pos = skb_network_header(skb) - skb->data;
383	h_pos = skb_transport_header(skb) - skb->data;
384
385	/* convert Ethernet header to proper 802.11 header (based on
386	* operation mode) */
387	ethertype = (skb->data[12] << 8) \| skb->data[13];
388	fc = cpu_to_le16(IEEE80211_FTYPE_DATA \| IEEE80211_STYPE_DATA);
389
390	switch (iftype) {
391	case NL80211_IFTYPE_AP:
392	case NL80211_IFTYPE_AP_VLAN:
393	fc \|= cpu_to_le16(IEEE80211_FCTL_FROMDS);
394	/* DA BSSID SA */
395	memcpy(hdr.addr1, skb->data, ETH_ALEN);
396	memcpy(hdr.addr2, addr, ETH_ALEN);
397	memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
398	hdrlen = 24;
399	break;
400	case NL80211_IFTYPE_STATION:
401	fc \|= cpu_to_le16(IEEE80211_FCTL_TODS);
402	/* BSSID SA DA */
403	memcpy(hdr.addr1, bssid, ETH_ALEN);
404	memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
405	memcpy(hdr.addr3, skb->data, ETH_ALEN);
406	hdrlen = 24;
407	break;
408	case NL80211_IFTYPE_ADHOC:
409	/* DA SA BSSID */
410	memcpy(hdr.addr1, skb->data, ETH_ALEN);
411	memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
412	memcpy(hdr.addr3, bssid, ETH_ALEN);
413	hdrlen = 24;
414	break;
415	default:
416	return -EOPNOTSUPP;
417	}
418
419	if (qos) {
420	fc \|= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
421	hdrlen += 2;
422	}
423
424	hdr.frame_control = fc;
425	hdr.duration_id = 0;
426	hdr.seq_ctrl = 0;
427
428	skip_header_bytes = ETH_HLEN;
429	if (ethertype == ETH_P_AARP \|\| ethertype == ETH_P_IPX) {
430	encaps_data = bridge_tunnel_header;
431	encaps_len = sizeof(bridge_tunnel_header);
432	skip_header_bytes -= 2;
433	} else if (ethertype > 0x600) {
434	encaps_data = rfc1042_header;
435	encaps_len = sizeof(rfc1042_header);
436	skip_header_bytes -= 2;
437	} else {
438	encaps_data = NULL;
439	encaps_len = 0;
440	}
441
442	skb_pull(skb, skip_header_bytes);
443	nh_pos -= skip_header_bytes;
444	h_pos -= skip_header_bytes;
445
446	head_need = hdrlen + encaps_len - skb_headroom(skb);
447
448	if (head_need > 0 \|\| skb_cloned(skb)) {
449	head_need = max(head_need, 0);
450	if (head_need)
451	skb_orphan(skb);
452
453	if (pskb_expand_head(skb, head_need, 0, GFP_ATOMIC)) {
454	printk(KERN_ERR "failed to reallocate Tx buffer\n");
455	return -ENOMEM;
456	}
457	skb->truesize += head_need;
458	}
459
460	if (encaps_data) {
461	memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
462	nh_pos += encaps_len;
463	h_pos += encaps_len;
464	}
465
466	memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
467
468	nh_pos += hdrlen;
469	h_pos += hdrlen;
470
471	/* Update skb pointers to various headers since this modified frame
472	* is going to go through Linux networking code that may potentially
473	* need things like pointer to IP header. */
474	skb_set_mac_header(skb, 0);
475	skb_set_network_header(skb, nh_pos);
476	skb_set_transport_header(skb, h_pos);
477
478	return 0;
479	}
480	EXPORT_SYMBOL(ieee80211_data_from_8023);
481
482	/* Given a data frame determine the 802.1p/1d tag to use. */
483	unsigned int cfg80211_classify8021d(struct sk_buff *skb)
484	{
485	unsigned int dscp;
486
487	/* skb->priority values from 256->263 are magic values to
488	* directly indicate a specific 802.1d priority. This is used
489	* to allow 802.1d priority to be passed directly in from VLAN
490	* tags, etc.
491	*/
492	if (skb->priority >= 256 && skb->priority <= 263)
493	return skb->priority - 256;
494
495	switch (skb->protocol) {
496	case htons(ETH_P_IP):
497	dscp = ip_hdr(skb)->tos & 0xfc;
498	break;
499	default:
500	return 0;
501	}
502
503	return dscp >> 5;
504	}
505	EXPORT_SYMBOL(cfg80211_classify8021d);