util.c 25.0 KB
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/*
 * Wireless utility functions
 *
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 * Copyright 2007-2009	Johannes Berg <johannes@sipsolutions.net>
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 */
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#include <linux/bitops.h>
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#include <linux/etherdevice.h>
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#include <linux/slab.h>
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#include <net/cfg80211.h>
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#include <net/ip.h>
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#include "core.h"

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struct ieee80211_rate *
ieee80211_get_response_rate(struct ieee80211_supported_band *sband,
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			    u32 basic_rates, int bitrate)
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{
	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);

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int ieee80211_channel_to_frequency(int chan, enum ieee80211_band band)
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{
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	/* see 802.11 17.3.8.3.2 and Annex J
	 * there are overlapping channel numbers in 5GHz and 2GHz bands */
	if (band == IEEE80211_BAND_5GHZ) {
		if (chan >= 182 && chan <= 196)
			return 4000 + chan * 5;
		else
			return 5000 + chan * 5;
	} else { /* IEEE80211_BAND_2GHZ */
		if (chan == 14)
			return 2484;
		else if (chan < 14)
			return 2407 + chan * 5;
		else
			return 0; /* not supported */
	}
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}
EXPORT_SYMBOL(ieee80211_channel_to_frequency);

int ieee80211_frequency_to_channel(int freq)
{
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	/* see 802.11 17.3.8.3.2 and Annex J */
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	if (freq == 2484)
		return 14;
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	else if (freq < 2484)
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		return (freq - 2407) / 5;
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	else if (freq >= 4910 && freq <= 4980)
		return (freq - 4000) / 5;
	else
		return (freq - 5000) / 5;
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}
EXPORT_SYMBOL(ieee80211_frequency_to_channel);

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struct ieee80211_channel *__ieee80211_get_channel(struct wiphy *wiphy,
						  int freq)
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{
	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;
}
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EXPORT_SYMBOL(__ieee80211_get_channel);
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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--;
			}

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			if (sband->bitrates[i].bitrate != 10 &&
			    sband->bitrates[i].bitrate != 20 &&
			    sband->bitrates[i].bitrate != 55 &&
			    sband->bitrates[i].bitrate != 110)
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				sband->bitrates[i].flags |=
					IEEE80211_RATE_ERP_G;
		}
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		WARN_ON(want != 0 && want != 3 && want != 6);
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		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);
}
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int cfg80211_validate_key_settings(struct cfg80211_registered_device *rdev,
				   struct key_params *params, int key_idx,
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				   bool pairwise, const u8 *mac_addr)
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{
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	int i;

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	if (key_idx > 5)
		return -EINVAL;

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	if (!pairwise && mac_addr && !(rdev->wiphy.flags & WIPHY_FLAG_IBSS_RSN))
		return -EINVAL;

	if (pairwise && !mac_addr)
		return -EINVAL;

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	/*
	 * Disallow pairwise keys with non-zero index unless it's WEP
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	 * or a vendor specific cipher (because current deployments use
	 * pairwise WEP keys with non-zero indices and for vendor specific
	 * ciphers this should be validated in the driver or hardware level
	 * - but 802.11i clearly specifies to use zero)
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	 */
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	if (pairwise && key_idx &&
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	    ((params->cipher == WLAN_CIPHER_SUITE_TKIP) ||
	     (params->cipher == WLAN_CIPHER_SUITE_CCMP) ||
	     (params->cipher == WLAN_CIPHER_SUITE_AES_CMAC)))
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		return -EINVAL;

	switch (params->cipher) {
	case WLAN_CIPHER_SUITE_WEP40:
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		if (params->key_len != WLAN_KEY_LEN_WEP40)
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			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_TKIP:
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		if (params->key_len != WLAN_KEY_LEN_TKIP)
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			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_CCMP:
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		if (params->key_len != WLAN_KEY_LEN_CCMP)
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			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_WEP104:
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		if (params->key_len != WLAN_KEY_LEN_WEP104)
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			return -EINVAL;
		break;
	case WLAN_CIPHER_SUITE_AES_CMAC:
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		if (params->key_len != WLAN_KEY_LEN_AES_CMAC)
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			return -EINVAL;
		break;
	default:
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		/*
		 * We don't know anything about this algorithm,
		 * allow using it -- but the driver must check
		 * all parameters! We still check below whether
		 * or not the driver supports this algorithm,
		 * of course.
		 */
		break;
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	}

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	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;
		}
	}

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	for (i = 0; i < rdev->wiphy.n_cipher_suites; i++)
		if (params->cipher == rdev->wiphy.cipher_suites[i])
			break;
	if (i == rdev->wiphy.n_cipher_suites)
		return -EINVAL;

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	return 0;
}
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/* 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);

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

	if (ieee80211_is_data(fc)) {
		if (ieee80211_has_a4(fc))
			hdrlen = 30;
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		if (ieee80211_is_data_qos(fc)) {
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			hdrlen += IEEE80211_QOS_CTL_LEN;
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			if (ieee80211_has_order(fc))
				hdrlen += IEEE80211_HT_CTL_LEN;
		}
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		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);

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static int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr)
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{
	int ae = meshhdr->flags & MESH_FLAGS_AE;
	/* 7.1.3.5a.2 */
	switch (ae) {
	case 0:
		return 6;
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	case MESH_FLAGS_AE_A4:
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		return 12;
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	case MESH_FLAGS_AE_A5_A6:
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		return 18;
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	case (MESH_FLAGS_AE_A4 | MESH_FLAGS_AE_A5_A6):
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		return 24;
	default:
		return 6;
	}
}

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int ieee80211_data_to_8023(struct sk_buff *skb, const u8 *addr,
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			   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 &&
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			     iftype != NL80211_IFTYPE_AP_VLAN &&
			     iftype != NL80211_IFTYPE_P2P_GO))
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			return -1;
		break;
	case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
		if (unlikely(iftype != NL80211_IFTYPE_WDS &&
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			     iftype != NL80211_IFTYPE_MESH_POINT &&
			     iftype != NL80211_IFTYPE_AP_VLAN &&
			     iftype != NL80211_IFTYPE_STATION))
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			return -1;
		if (iftype == NL80211_IFTYPE_MESH_POINT) {
			struct ieee80211s_hdr *meshdr =
				(struct ieee80211s_hdr *) (skb->data + hdrlen);
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			/* make sure meshdr->flags is on the linear part */
			if (!pskb_may_pull(skb, hdrlen + 1))
				return -1;
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			if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
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				skb_copy_bits(skb, hdrlen +
					offsetof(struct ieee80211s_hdr, eaddr1),
				       	dst, ETH_ALEN);
				skb_copy_bits(skb, hdrlen +
					offsetof(struct ieee80211s_hdr, eaddr2),
				        src, ETH_ALEN);
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			}
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			hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
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		}
		break;
	case cpu_to_le16(IEEE80211_FCTL_FROMDS):
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		if ((iftype != NL80211_IFTYPE_STATION &&
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		     iftype != NL80211_IFTYPE_P2P_CLIENT &&
		     iftype != NL80211_IFTYPE_MESH_POINT) ||
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		    (is_multicast_ether_addr(dst) &&
		     !compare_ether_addr(src, addr)))
			return -1;
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		if (iftype == NL80211_IFTYPE_MESH_POINT) {
			struct ieee80211s_hdr *meshdr =
				(struct ieee80211s_hdr *) (skb->data + hdrlen);
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			/* make sure meshdr->flags is on the linear part */
			if (!pskb_may_pull(skb, hdrlen + 1))
				return -1;
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			if (meshdr->flags & MESH_FLAGS_AE_A4)
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				skb_copy_bits(skb, hdrlen +
					offsetof(struct ieee80211s_hdr, eaddr1),
					src, ETH_ALEN);
			hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
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		}
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		break;
	case cpu_to_le16(0):
		if (iftype != NL80211_IFTYPE_ADHOC)
			return -1;
		break;
	}

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	if (!pskb_may_pull(skb, hdrlen + 8))
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		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);

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int ieee80211_data_from_8023(struct sk_buff *skb, const u8 *addr,
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			     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:
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	case NL80211_IFTYPE_P2P_GO:
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		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:
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	case NL80211_IFTYPE_P2P_CLIENT:
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		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)) {
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			pr_err("failed to reallocate Tx buffer\n");
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			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);

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void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list,
			      const u8 *addr, enum nl80211_iftype iftype,
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			      const unsigned int extra_headroom,
			      bool has_80211_header)
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{
	struct sk_buff *frame = NULL;
	u16 ethertype;
	u8 *payload;
	const struct ethhdr *eth;
	int remaining, err;
	u8 dst[ETH_ALEN], src[ETH_ALEN];

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	if (has_80211_header) {
		err = ieee80211_data_to_8023(skb, addr, iftype);
		if (err)
			goto out;
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		/* skip the wrapping header */
		eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
		if (!eth)
			goto out;
	} else {
		eth = (struct ethhdr *) skb->data;
	}
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	while (skb != frame) {
		u8 padding;
		__be16 len = eth->h_proto;
		unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);

		remaining = skb->len;
		memcpy(dst, eth->h_dest, ETH_ALEN);
		memcpy(src, eth->h_source, ETH_ALEN);

		padding = (4 - subframe_len) & 0x3;
		/* the last MSDU has no padding */
		if (subframe_len > remaining)
			goto purge;

		skb_pull(skb, sizeof(struct ethhdr));
		/* reuse skb for the last subframe */
		if (remaining <= subframe_len + padding)
			frame = skb;
		else {
			unsigned int hlen = ALIGN(extra_headroom, 4);
			/*
			 * Allocate and reserve two bytes more for payload
			 * alignment since sizeof(struct ethhdr) is 14.
			 */
			frame = dev_alloc_skb(hlen + subframe_len + 2);
			if (!frame)
				goto purge;

			skb_reserve(frame, hlen + sizeof(struct ethhdr) + 2);
			memcpy(skb_put(frame, ntohs(len)), skb->data,
				ntohs(len));

			eth = (struct ethhdr *)skb_pull(skb, ntohs(len) +
							padding);
			if (!eth) {
				dev_kfree_skb(frame);
				goto purge;
			}
		}

		skb_reset_network_header(frame);
		frame->dev = skb->dev;
		frame->priority = skb->priority;

		payload = frame->data;
		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(frame, 6);
			memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
			memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
		} else {
			memcpy(skb_push(frame, sizeof(__be16)), &len,
				sizeof(__be16));
			memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
			memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
		}
		__skb_queue_tail(list, frame);
	}

	return;

 purge:
	__skb_queue_purge(list);
 out:
	dev_kfree_skb(skb);
}
EXPORT_SYMBOL(ieee80211_amsdu_to_8023s);

644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667
/* 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);
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const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 ie)
{
	u8 *end, *pos;

	pos = bss->information_elements;
	if (pos == NULL)
		return NULL;
	end = pos + bss->len_information_elements;

	while (pos + 1 < end) {
		if (pos + 2 + pos[1] > end)
			break;
		if (pos[0] == ie)
			return pos;
		pos += 2 + pos[1];
	}

	return NULL;
}
EXPORT_SYMBOL(ieee80211_bss_get_ie);
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void cfg80211_upload_connect_keys(struct wireless_dev *wdev)
{
	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
	struct net_device *dev = wdev->netdev;
	int i;

	if (!wdev->connect_keys)
		return;

	for (i = 0; i < 6; i++) {
		if (!wdev->connect_keys->params[i].cipher)
			continue;
702
		if (rdev->ops->add_key(wdev->wiphy, dev, i, false, NULL,
703
					&wdev->connect_keys->params[i])) {
704
			netdev_err(dev, "failed to set key %d\n", i);
705 706
			continue;
		}
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Johannes Berg 已提交
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		if (wdev->connect_keys->def == i)
708 709
			if (rdev->ops->set_default_key(wdev->wiphy, dev,
						       i, true, true)) {
710
				netdev_err(dev, "failed to set defkey %d\n", i);
711 712
				continue;
			}
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Johannes Berg 已提交
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		if (wdev->connect_keys->defmgmt == i)
			if (rdev->ops->set_default_mgmt_key(wdev->wiphy, dev, i))
715
				netdev_err(dev, "failed to set mgtdef %d\n", i);
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Johannes Berg 已提交
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	}

	kfree(wdev->connect_keys);
	wdev->connect_keys = NULL;
}
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static void cfg80211_process_wdev_events(struct wireless_dev *wdev)
{
	struct cfg80211_event *ev;
	unsigned long flags;
	const u8 *bssid = NULL;

	spin_lock_irqsave(&wdev->event_lock, flags);
	while (!list_empty(&wdev->event_list)) {
		ev = list_first_entry(&wdev->event_list,
				      struct cfg80211_event, list);
		list_del(&ev->list);
		spin_unlock_irqrestore(&wdev->event_lock, flags);

		wdev_lock(wdev);
		switch (ev->type) {
		case EVENT_CONNECT_RESULT:
			if (!is_zero_ether_addr(ev->cr.bssid))
				bssid = ev->cr.bssid;
			__cfg80211_connect_result(
				wdev->netdev, bssid,
				ev->cr.req_ie, ev->cr.req_ie_len,
				ev->cr.resp_ie, ev->cr.resp_ie_len,
				ev->cr.status,
				ev->cr.status == WLAN_STATUS_SUCCESS,
				NULL);
			break;
		case EVENT_ROAMED:
			__cfg80211_roamed(wdev, ev->rm.bssid,
					  ev->rm.req_ie, ev->rm.req_ie_len,
					  ev->rm.resp_ie, ev->rm.resp_ie_len);
			break;
		case EVENT_DISCONNECTED:
			__cfg80211_disconnected(wdev->netdev,
						ev->dc.ie, ev->dc.ie_len,
						ev->dc.reason, true);
			break;
		case EVENT_IBSS_JOINED:
			__cfg80211_ibss_joined(wdev->netdev, ev->ij.bssid);
			break;
		}
		wdev_unlock(wdev);

		kfree(ev);

		spin_lock_irqsave(&wdev->event_lock, flags);
	}
	spin_unlock_irqrestore(&wdev->event_lock, flags);
}

void cfg80211_process_rdev_events(struct cfg80211_registered_device *rdev)
{
	struct wireless_dev *wdev;

	ASSERT_RTNL();
	ASSERT_RDEV_LOCK(rdev);

	mutex_lock(&rdev->devlist_mtx);

	list_for_each_entry(wdev, &rdev->netdev_list, list)
		cfg80211_process_wdev_events(wdev);

	mutex_unlock(&rdev->devlist_mtx);
}

int cfg80211_change_iface(struct cfg80211_registered_device *rdev,
			  struct net_device *dev, enum nl80211_iftype ntype,
			  u32 *flags, struct vif_params *params)
{
	int err;
	enum nl80211_iftype otype = dev->ieee80211_ptr->iftype;

	ASSERT_RDEV_LOCK(rdev);

	/* don't support changing VLANs, you just re-create them */
	if (otype == NL80211_IFTYPE_AP_VLAN)
		return -EOPNOTSUPP;

	if (!rdev->ops->change_virtual_intf ||
	    !(rdev->wiphy.interface_modes & (1 << ntype)))
		return -EOPNOTSUPP;

803
	/* if it's part of a bridge, reject changing type to station/ibss */
804
	if ((dev->priv_flags & IFF_BRIDGE_PORT) &&
805 806 807
	    (ntype == NL80211_IFTYPE_ADHOC ||
	     ntype == NL80211_IFTYPE_STATION ||
	     ntype == NL80211_IFTYPE_P2P_CLIENT))
808 809
		return -EBUSY;

810
	if (ntype != otype) {
811 812 813 814 815
		err = cfg80211_can_change_interface(rdev, dev->ieee80211_ptr,
						    ntype);
		if (err)
			return err;

816
		dev->ieee80211_ptr->use_4addr = false;
817
		dev->ieee80211_ptr->mesh_id_up_len = 0;
818

819 820 821 822 823
		switch (otype) {
		case NL80211_IFTYPE_ADHOC:
			cfg80211_leave_ibss(rdev, dev, false);
			break;
		case NL80211_IFTYPE_STATION:
824
		case NL80211_IFTYPE_P2P_CLIENT:
825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842
			cfg80211_disconnect(rdev, dev,
					    WLAN_REASON_DEAUTH_LEAVING, true);
			break;
		case NL80211_IFTYPE_MESH_POINT:
			/* mesh should be handled? */
			break;
		default:
			break;
		}

		cfg80211_process_rdev_events(rdev);
	}

	err = rdev->ops->change_virtual_intf(&rdev->wiphy, dev,
					     ntype, flags, params);

	WARN_ON(!err && dev->ieee80211_ptr->iftype != ntype);

843 844 845
	if (!err && params && params->use_4addr != -1)
		dev->ieee80211_ptr->use_4addr = params->use_4addr;

846 847 848 849 850 851 852
	if (!err) {
		dev->priv_flags &= ~IFF_DONT_BRIDGE;
		switch (ntype) {
		case NL80211_IFTYPE_STATION:
			if (dev->ieee80211_ptr->use_4addr)
				break;
			/* fall through */
853
		case NL80211_IFTYPE_P2P_CLIENT:
854 855 856
		case NL80211_IFTYPE_ADHOC:
			dev->priv_flags |= IFF_DONT_BRIDGE;
			break;
857
		case NL80211_IFTYPE_P2P_GO:
858 859 860 861 862 863 864 865 866 867
		case NL80211_IFTYPE_AP:
		case NL80211_IFTYPE_AP_VLAN:
		case NL80211_IFTYPE_WDS:
		case NL80211_IFTYPE_MESH_POINT:
			/* bridging OK */
			break;
		case NL80211_IFTYPE_MONITOR:
			/* monitor can't bridge anyway */
			break;
		case NL80211_IFTYPE_UNSPECIFIED:
868
		case NUM_NL80211_IFTYPES:
869 870 871 872 873
			/* not happening */
			break;
		}
	}

874 875
	return err;
}
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u16 cfg80211_calculate_bitrate(struct rate_info *rate)
{
	int modulation, streams, bitrate;

	if (!(rate->flags & RATE_INFO_FLAGS_MCS))
		return rate->legacy;

	/* the formula below does only work for MCS values smaller than 32 */
	if (rate->mcs >= 32)
		return 0;

	modulation = rate->mcs & 7;
	streams = (rate->mcs >> 3) + 1;

	bitrate = (rate->flags & RATE_INFO_FLAGS_40_MHZ_WIDTH) ?
			13500000 : 6500000;

	if (modulation < 4)
		bitrate *= (modulation + 1);
	else if (modulation == 4)
		bitrate *= (modulation + 2);
	else
		bitrate *= (modulation + 3);

	bitrate *= streams;

	if (rate->flags & RATE_INFO_FLAGS_SHORT_GI)
		bitrate = (bitrate / 9) * 10;

	/* do NOT round down here */
	return (bitrate + 50000) / 100000;
}
909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933

int cfg80211_validate_beacon_int(struct cfg80211_registered_device *rdev,
				 u32 beacon_int)
{
	struct wireless_dev *wdev;
	int res = 0;

	if (!beacon_int)
		return -EINVAL;

	mutex_lock(&rdev->devlist_mtx);

	list_for_each_entry(wdev, &rdev->netdev_list, list) {
		if (!wdev->beacon_interval)
			continue;
		if (wdev->beacon_interval != beacon_int) {
			res = -EINVAL;
			break;
		}
	}

	mutex_unlock(&rdev->devlist_mtx);

	return res;
}
934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008

int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev,
				  struct wireless_dev *wdev,
				  enum nl80211_iftype iftype)
{
	struct wireless_dev *wdev_iter;
	int num[NUM_NL80211_IFTYPES];
	int total = 1;
	int i, j;

	ASSERT_RTNL();

	/* Always allow software iftypes */
	if (rdev->wiphy.software_iftypes & BIT(iftype))
		return 0;

	/*
	 * Drivers will gradually all set this flag, until all
	 * have it we only enforce for those that set it.
	 */
	if (!(rdev->wiphy.flags & WIPHY_FLAG_ENFORCE_COMBINATIONS))
		return 0;

	memset(num, 0, sizeof(num));

	num[iftype] = 1;

	mutex_lock(&rdev->devlist_mtx);
	list_for_each_entry(wdev_iter, &rdev->netdev_list, list) {
		if (wdev_iter == wdev)
			continue;
		if (!netif_running(wdev_iter->netdev))
			continue;

		if (rdev->wiphy.software_iftypes & BIT(wdev_iter->iftype))
			continue;

		num[wdev_iter->iftype]++;
		total++;
	}
	mutex_unlock(&rdev->devlist_mtx);

	for (i = 0; i < rdev->wiphy.n_iface_combinations; i++) {
		const struct ieee80211_iface_combination *c;
		struct ieee80211_iface_limit *limits;

		c = &rdev->wiphy.iface_combinations[i];

		limits = kmemdup(c->limits, sizeof(limits[0]) * c->n_limits,
				 GFP_KERNEL);
		if (!limits)
			return -ENOMEM;
		if (total > c->max_interfaces)
			goto cont;

		for (iftype = 0; iftype < NUM_NL80211_IFTYPES; iftype++) {
			if (rdev->wiphy.software_iftypes & BIT(iftype))
				continue;
			for (j = 0; j < c->n_limits; j++) {
				if (!(limits[j].types & iftype))
					continue;
				if (limits[j].max < num[iftype])
					goto cont;
				limits[j].max -= num[iftype];
			}
		}
		/* yay, it fits */
		kfree(limits);
		return 0;
 cont:
		kfree(limits);
	}

	return -EBUSY;
}