[deliverable/linux.git] / net / mac80211 / wpa.c

/*
 * Copyright 2002-2004, Instant802 Networks, Inc.
 *
 * 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.
 */

#include <linux/netdevice.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/skbuff.h>
#include <linux/compiler.h>
#include <net/iw_handler.h>

#include <net/mac80211.h>
#include "ieee80211_common.h"
#include "ieee80211_i.h"
#include "michael.h"
#include "tkip.h"
#include "aes_ccm.h"
#include "wpa.h"

static int ieee80211_get_hdr_info(const struct sk_buff *skb, u8 **sa, u8 **da,
				  u8 *qos_tid, u8 **data, size_t *data_len)
{
	struct ieee80211_hdr *hdr;
	size_t hdrlen;
	u16 fc;
	int a4_included;
	u8 *pos;

	hdr = (struct ieee80211_hdr *) skb->data;
	fc = le16_to_cpu(hdr->frame_control);

	hdrlen = 24;
	if ((fc & (IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS)) ==
	    (IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS)) {
		hdrlen += ETH_ALEN;
		*sa = hdr->addr4;
		*da = hdr->addr3;
	} else if (fc & IEEE80211_FCTL_FROMDS) {
		*sa = hdr->addr3;
		*da = hdr->addr1;
	} else if (fc & IEEE80211_FCTL_TODS) {
		*sa = hdr->addr2;
		*da = hdr->addr3;
	} else {
		*sa = hdr->addr2;
		*da = hdr->addr1;
	}

	if (fc & 0x80)
		hdrlen += 2;

	*data = skb->data + hdrlen;
	*data_len = skb->len - hdrlen;

	a4_included = (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
		(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS);
	if ((fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
	    fc & IEEE80211_STYPE_QOS_DATA) {
		pos = (u8 *) &hdr->addr4;
		if (a4_included)
			pos += 6;
		*qos_tid = pos[0] & 0x0f;
		*qos_tid |= 0x80; /* qos_included flag */
	} else
		*qos_tid = 0;

	return skb->len < hdrlen ? -1 : 0;
}


ieee80211_txrx_result
ieee80211_tx_h_michael_mic_add(struct ieee80211_txrx_data *tx)
{
	u8 *data, *sa, *da, *key, *mic, qos_tid;
	size_t data_len;
	u16 fc;
	struct sk_buff *skb = tx->skb;
	int authenticator;
	int wpa_test = 0;

	fc = tx->fc;

	if (!tx->key || tx->key->alg != ALG_TKIP || skb->len < 24 ||
	    !WLAN_FC_DATA_PRESENT(fc))
		return TXRX_CONTINUE;

	if (ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len))
		return TXRX_DROP;

	if (!tx->key->force_sw_encrypt &&
	    !tx->fragmented &&
	    !(tx->local->hw.flags & IEEE80211_HW_TKIP_INCLUDE_MMIC) &&
	    !wpa_test) {
		/* hwaccel - with no need for preallocated room for Michael MIC
		 */
		return TXRX_CONTINUE;
	}

	if (skb_tailroom(skb) < MICHAEL_MIC_LEN) {
		I802_DEBUG_INC(tx->local->tx_expand_skb_head);
		if (unlikely(pskb_expand_head(skb, TKIP_IV_LEN,
					      MICHAEL_MIC_LEN + TKIP_ICV_LEN,
					      GFP_ATOMIC))) {
			printk(KERN_DEBUG "%s: failed to allocate more memory "
			       "for Michael MIC\n", tx->dev->name);
			return TXRX_DROP;
		}
	}

#if 0
	authenticator = fc & IEEE80211_FCTL_FROMDS; /* FIX */
#else
	authenticator = 1;
#endif
	key = &tx->key->key[authenticator ? ALG_TKIP_TEMP_AUTH_TX_MIC_KEY :
			    ALG_TKIP_TEMP_AUTH_RX_MIC_KEY];
	mic = skb_put(skb, MICHAEL_MIC_LEN);
	michael_mic(key, da, sa, qos_tid & 0x0f, data, data_len, mic);

	return TXRX_CONTINUE;
}


ieee80211_txrx_result
ieee80211_rx_h_michael_mic_verify(struct ieee80211_txrx_data *rx)
{
	u8 *data, *sa, *da, *key = NULL, qos_tid;
	size_t data_len;
	u16 fc;
	u8 mic[MICHAEL_MIC_LEN];
	struct sk_buff *skb = rx->skb;
	int authenticator = 1, wpa_test = 0;

	fc = rx->fc;

	/* If device handles decryption totally, skip this check */
	if ((rx->local->hw.flags & IEEE80211_HW_DEVICE_HIDES_WEP) ||
	    (rx->local->hw.flags & IEEE80211_HW_DEVICE_STRIPS_MIC))
		return TXRX_CONTINUE;

	if (!rx->key || rx->key->alg != ALG_TKIP ||
	    !(rx->fc & IEEE80211_FCTL_PROTECTED) || !WLAN_FC_DATA_PRESENT(fc))
		return TXRX_CONTINUE;

	if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&
	    !rx->key->force_sw_encrypt) {
		if (rx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV) {
			if (skb->len < MICHAEL_MIC_LEN)
				return TXRX_DROP;
		}
		/* Need to verify Michael MIC sometimes in software even when
		 * hwaccel is used. Atheros ar5212: fragmented frames and QoS
		 * frames. */
		if (!rx->fragmented && !wpa_test)
			goto remove_mic;
	}

	if (ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len)
	    || data_len < MICHAEL_MIC_LEN)
		return TXRX_DROP;

	data_len -= MICHAEL_MIC_LEN;

#if 0
	authenticator = fc & IEEE80211_FCTL_TODS; /* FIX */
#else
	authenticator = 1;
#endif
	key = &rx->key->key[authenticator ? ALG_TKIP_TEMP_AUTH_RX_MIC_KEY :
			    ALG_TKIP_TEMP_AUTH_TX_MIC_KEY];
	michael_mic(key, da, sa, qos_tid & 0x0f, data, data_len, mic);
	if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0 || wpa_test) {
		if (!rx->u.rx.ra_match)
			return TXRX_DROP;

		printk(KERN_DEBUG "%s: invalid Michael MIC in data frame from "
		       MAC_FMT "\n", rx->dev->name, MAC_ARG(sa));

		do {
			struct ieee80211_hdr *hdr;
			union iwreq_data wrqu;
			char *buf = kmalloc(128, GFP_ATOMIC);
			if (!buf)
				break;

			/* TODO: needed parameters: count, key type, TSC */
			hdr = (struct ieee80211_hdr *) skb->data;
			sprintf(buf, "MLME-MICHAELMICFAILURE.indication("
				"keyid=%d %scast addr=" MAC_FMT ")",
				rx->key->keyidx,
				hdr->addr1[0] & 0x01 ? "broad" : "uni",
				MAC_ARG(hdr->addr2));
			memset(&wrqu, 0, sizeof(wrqu));
			wrqu.data.length = strlen(buf);
			wireless_send_event(rx->dev, IWEVCUSTOM, &wrqu, buf);
			kfree(buf);
		} while (0);

		if (!rx->local->apdev)
			return TXRX_DROP;

		ieee80211_rx_mgmt(rx->local, rx->skb, rx->u.rx.status,
				  ieee80211_msg_michael_mic_failure);

		return TXRX_QUEUED;
	}

 remove_mic:
	/* remove Michael MIC from payload */
	skb_trim(skb, skb->len - MICHAEL_MIC_LEN);

	return TXRX_CONTINUE;
}


static int tkip_encrypt_skb(struct ieee80211_txrx_data *tx,
			    struct sk_buff *skb, int test)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
	struct ieee80211_key *key = tx->key;
	int hdrlen, len, tailneed;
	u16 fc;
	u8 *pos;

	fc = le16_to_cpu(hdr->frame_control);
	hdrlen = ieee80211_get_hdrlen(fc);
	len = skb->len - hdrlen;

	tailneed = !tx->key->force_sw_encrypt ? 0 : TKIP_ICV_LEN;
	if ((skb_headroom(skb) < TKIP_IV_LEN ||
	     skb_tailroom(skb) < tailneed)) {
		I802_DEBUG_INC(tx->local->tx_expand_skb_head);
		if (unlikely(pskb_expand_head(skb, TKIP_IV_LEN, tailneed,
					      GFP_ATOMIC)))
			return -1;
	}

	pos = skb_push(skb, TKIP_IV_LEN);
	memmove(pos, pos + TKIP_IV_LEN, hdrlen);
	pos += hdrlen;

	/* Increase IV for the frame */
	key->u.tkip.iv16++;
	if (key->u.tkip.iv16 == 0)
		key->u.tkip.iv32++;

	if (!tx->key->force_sw_encrypt) {
		u32 flags = tx->local->hw.flags;
		hdr = (struct ieee80211_hdr *)skb->data;

		/* hwaccel - with preallocated room for IV */
		ieee80211_tkip_add_iv(pos, key,
				      (u8) (key->u.tkip.iv16 >> 8),
				      (u8) (((key->u.tkip.iv16 >> 8) | 0x20) &
					    0x7f),
				      (u8) key->u.tkip.iv16);

		if (flags & IEEE80211_HW_TKIP_REQ_PHASE2_KEY)
			ieee80211_tkip_gen_rc4key(key, hdr->addr2,
						  tx->u.tx.control->tkip_key);
		else if (flags & IEEE80211_HW_TKIP_REQ_PHASE1_KEY) {
			if (key->u.tkip.iv16 == 0 ||
			    !key->u.tkip.tx_initialized) {
				ieee80211_tkip_gen_phase1key(key, hdr->addr2,
					    (u16 *)tx->u.tx.control->tkip_key);
				key->u.tkip.tx_initialized = 1;
				tx->u.tx.control->flags |=
					    IEEE80211_TXCTL_TKIP_NEW_PHASE1_KEY;
			} else
				tx->u.tx.control->flags &=
					    ~IEEE80211_TXCTL_TKIP_NEW_PHASE1_KEY;
		}

		tx->u.tx.control->key_idx = tx->key->hw_key_idx;
		return 0;
	}

	/* Add room for ICV */
	skb_put(skb, TKIP_ICV_LEN);

	hdr = (struct ieee80211_hdr *) skb->data;
	ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
				    key, pos, len, hdr->addr2);
	return 0;
}


ieee80211_txrx_result
ieee80211_tx_h_tkip_encrypt(struct ieee80211_txrx_data *tx)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;
	u16 fc;
	struct ieee80211_key *key = tx->key;
	struct sk_buff *skb = tx->skb;
	int wpa_test = 0, test = 0;

	fc = le16_to_cpu(hdr->frame_control);

	if (!key || key->alg != ALG_TKIP || !WLAN_FC_DATA_PRESENT(fc))
		return TXRX_CONTINUE;

	tx->u.tx.control->icv_len = TKIP_ICV_LEN;
	tx->u.tx.control->iv_len = TKIP_IV_LEN;
	ieee80211_tx_set_iswep(tx);

	if (!tx->key->force_sw_encrypt &&
	    !(tx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV) &&
	    !wpa_test) {
		/* hwaccel - with no need for preallocated room for IV/ICV */
		tx->u.tx.control->key_idx = tx->key->hw_key_idx;
		return TXRX_CONTINUE;
	}

	if (tkip_encrypt_skb(tx, skb, test) < 0)
		return TXRX_DROP;

	if (tx->u.tx.extra_frag) {
		int i;
		for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
			if (tkip_encrypt_skb(tx, tx->u.tx.extra_frag[i], test)
			    < 0)
				return TXRX_DROP;
		}
	}

	return TXRX_CONTINUE;
}


ieee80211_txrx_result
ieee80211_rx_h_tkip_decrypt(struct ieee80211_txrx_data *rx)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
	u16 fc;
	int hdrlen, res, hwaccel = 0, wpa_test = 0;
	struct ieee80211_key *key = rx->key;
	struct sk_buff *skb = rx->skb;

	fc = le16_to_cpu(hdr->frame_control);
	hdrlen = ieee80211_get_hdrlen(fc);

	if (!rx->key || rx->key->alg != ALG_TKIP ||
	    !(rx->fc & IEEE80211_FCTL_PROTECTED) ||
	    (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
		return TXRX_CONTINUE;

	if (!rx->sta || skb->len - hdrlen < 12)
		return TXRX_DROP;

	if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&
	    !rx->key->force_sw_encrypt) {
		if (!(rx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV)) {
			/* Hardware takes care of all processing, including
			 * replay protection, so no need to continue here. */
			return TXRX_CONTINUE;
		}

		/* let TKIP code verify IV, but skip decryption */
		hwaccel = 1;
	}

	res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,
					  key, skb->data + hdrlen,
					  skb->len - hdrlen, rx->sta->addr,
					  hwaccel, rx->u.rx.queue);
	if (res != TKIP_DECRYPT_OK || wpa_test) {
		printk(KERN_DEBUG "%s: TKIP decrypt failed for RX frame from "
		       MAC_FMT " (res=%d)\n",
		       rx->dev->name, MAC_ARG(rx->sta->addr), res);
		return TXRX_DROP;
	}

	/* Trim ICV */
	skb_trim(skb, skb->len - TKIP_ICV_LEN);

	/* Remove IV */
	memmove(skb->data + TKIP_IV_LEN, skb->data, hdrlen);
	skb_pull(skb, TKIP_IV_LEN);

	return TXRX_CONTINUE;
}


static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad,
				int encrypted)
{
	u16 fc;
	int a4_included, qos_included;
	u8 qos_tid, *fc_pos, *data, *sa, *da;
	int len_a;
	size_t data_len;
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;

	fc_pos = (u8 *) &hdr->frame_control;
	fc = fc_pos[0] ^ (fc_pos[1] << 8);
	a4_included = (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
		(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS);

	ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len);
	data_len -= CCMP_HDR_LEN + (encrypted ? CCMP_MIC_LEN : 0);
	if (qos_tid & 0x80) {
		qos_included = 1;
		qos_tid &= 0x0f;
	} else
		qos_included = 0;
	/* First block, b_0 */

	b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */
	/* Nonce: QoS Priority | A2 | PN */
	b_0[1] = qos_tid;
	memcpy(&b_0[2], hdr->addr2, 6);
	memcpy(&b_0[8], pn, CCMP_PN_LEN);
	/* l(m) */
	b_0[14] = (data_len >> 8) & 0xff;
	b_0[15] = data_len & 0xff;


	/* AAD (extra authenticate-only data) / masked 802.11 header
	 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */

	len_a = a4_included ? 28 : 22;
	if (qos_included)
		len_a += 2;

	aad[0] = 0; /* (len_a >> 8) & 0xff; */
	aad[1] = len_a & 0xff;
	/* Mask FC: zero subtype b4 b5 b6 */
	aad[2] = fc_pos[0] & ~(BIT(4) | BIT(5) | BIT(6));
	/* Retry, PwrMgt, MoreData; set Protected */
	aad[3] = (fc_pos[1] & ~(BIT(3) | BIT(4) | BIT(5))) | BIT(6);
	memcpy(&aad[4], &hdr->addr1, 18);

	/* Mask Seq#, leave Frag# */
	aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
	aad[23] = 0;
	if (a4_included) {
		memcpy(&aad[24], hdr->addr4, 6);
		aad[30] = 0;
		aad[31] = 0;
	} else
		memset(&aad[24], 0, 8);
	if (qos_included) {
		u8 *dpos = &aad[a4_included ? 30 : 24];

		/* Mask QoS Control field */
		dpos[0] = qos_tid;
		dpos[1] = 0;
	}
}


static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
{
	hdr[0] = pn[5];
	hdr[1] = pn[4];
	hdr[2] = 0;
	hdr[3] = 0x20 | (key_id << 6);
	hdr[4] = pn[3];
	hdr[5] = pn[2];
	hdr[6] = pn[1];
	hdr[7] = pn[0];
}


static inline int ccmp_hdr2pn(u8 *pn, u8 *hdr)
{
	pn[0] = hdr[7];
	pn[1] = hdr[6];
	pn[2] = hdr[5];
	pn[3] = hdr[4];
	pn[4] = hdr[1];
	pn[5] = hdr[0];
	return (hdr[3] >> 6) & 0x03;
}


static int ccmp_encrypt_skb(struct ieee80211_txrx_data *tx,
			    struct sk_buff *skb, int test)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
	struct ieee80211_key *key = tx->key;
	int hdrlen, len, tailneed;
	u16 fc;
	u8 *pos, *pn, *b_0, *aad, *scratch;
	int i;

	scratch = key->u.ccmp.tx_crypto_buf;
	b_0 = scratch + 3 * AES_BLOCK_LEN;
	aad = scratch + 4 * AES_BLOCK_LEN;

	fc = le16_to_cpu(hdr->frame_control);
	hdrlen = ieee80211_get_hdrlen(fc);
	len = skb->len - hdrlen;

	tailneed = !key->force_sw_encrypt ? 0 : CCMP_MIC_LEN;

	if ((skb_headroom(skb) < CCMP_HDR_LEN ||
	     skb_tailroom(skb) < tailneed)) {
		I802_DEBUG_INC(tx->local->tx_expand_skb_head);
		if (unlikely(pskb_expand_head(skb, CCMP_HDR_LEN, tailneed,
					      GFP_ATOMIC)))
			return -1;
	}

	pos = skb_push(skb, CCMP_HDR_LEN);
	memmove(pos, pos + CCMP_HDR_LEN, hdrlen);
	hdr = (struct ieee80211_hdr *) pos;
	pos += hdrlen;

	/* PN = PN + 1 */
	pn = key->u.ccmp.tx_pn;

	for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
		pn[i]++;
		if (pn[i])
			break;
	}

	ccmp_pn2hdr(pos, pn, key->keyidx);

	if (!key->force_sw_encrypt) {
		/* hwaccel - with preallocated room for CCMP header */
		tx->u.tx.control->key_idx = key->hw_key_idx;
		return 0;
	}

	pos += CCMP_HDR_LEN;
	ccmp_special_blocks(skb, pn, b_0, aad, 0);
	ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, scratch, b_0, aad, pos, len,
				  pos, skb_put(skb, CCMP_MIC_LEN));

	return 0;
}


ieee80211_txrx_result
ieee80211_tx_h_ccmp_encrypt(struct ieee80211_txrx_data *tx)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;
	struct ieee80211_key *key = tx->key;
	u16 fc;
	struct sk_buff *skb = tx->skb;
	int test = 0;

	fc = le16_to_cpu(hdr->frame_control);

	if (!key || key->alg != ALG_CCMP || !WLAN_FC_DATA_PRESENT(fc))
		return TXRX_CONTINUE;

	tx->u.tx.control->icv_len = CCMP_MIC_LEN;
	tx->u.tx.control->iv_len = CCMP_HDR_LEN;
	ieee80211_tx_set_iswep(tx);

	if (!tx->key->force_sw_encrypt &&
	    !(tx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV)) {
		/* hwaccel - with no need for preallocated room for CCMP "
		 * header or MIC fields */
		tx->u.tx.control->key_idx = tx->key->hw_key_idx;
		return TXRX_CONTINUE;
	}

	if (ccmp_encrypt_skb(tx, skb, test) < 0)
		return TXRX_DROP;

	if (tx->u.tx.extra_frag) {
		int i;

		for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
			if (ccmp_encrypt_skb(tx, tx->u.tx.extra_frag[i], test)
			    < 0)
				return TXRX_DROP;
		}
	}

	return TXRX_CONTINUE;
}


ieee80211_txrx_result
ieee80211_rx_h_ccmp_decrypt(struct ieee80211_txrx_data *rx)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
	u16 fc;
	int hdrlen;
	struct ieee80211_key *key = rx->key;
	struct sk_buff *skb = rx->skb;
	u8 pn[CCMP_PN_LEN];
	int data_len;

	fc = le16_to_cpu(hdr->frame_control);
	hdrlen = ieee80211_get_hdrlen(fc);

	if (!key || key->alg != ALG_CCMP ||
	    !(rx->fc & IEEE80211_FCTL_PROTECTED) ||
	    (rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
		return TXRX_CONTINUE;

	data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN;
	if (!rx->sta || data_len < 0)
		return TXRX_DROP;

	if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&
	    !key->force_sw_encrypt &&
	    !(rx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV))
		return TXRX_CONTINUE;

	(void) ccmp_hdr2pn(pn, skb->data + hdrlen);

	if (memcmp(pn, key->u.ccmp.rx_pn[rx->u.rx.queue], CCMP_PN_LEN) <= 0) {
#ifdef CONFIG_MAC80211_DEBUG
		u8 *ppn = key->u.ccmp.rx_pn[rx->u.rx.queue];
		printk(KERN_DEBUG "%s: CCMP replay detected for RX frame from "
		       MAC_FMT " (RX PN %02x%02x%02x%02x%02x%02x <= prev. PN "
		       "%02x%02x%02x%02x%02x%02x)\n", rx->dev->name,
		       MAC_ARG(rx->sta->addr),
		       pn[0], pn[1], pn[2], pn[3], pn[4], pn[5],
		       ppn[0], ppn[1], ppn[2], ppn[3], ppn[4], ppn[5]);
#endif /* CONFIG_MAC80211_DEBUG */
		key->u.ccmp.replays++;
		return TXRX_DROP;
	}

	if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&
	    !key->force_sw_encrypt) {
		/* hwaccel has already decrypted frame and verified MIC */
	} else {
		u8 *scratch, *b_0, *aad;

		scratch = key->u.ccmp.rx_crypto_buf;
		b_0 = scratch + 3 * AES_BLOCK_LEN;
		aad = scratch + 4 * AES_BLOCK_LEN;

		ccmp_special_blocks(skb, pn, b_0, aad, 1);

		if (ieee80211_aes_ccm_decrypt(
			    key->u.ccmp.tfm, scratch, b_0, aad,
			    skb->data + hdrlen + CCMP_HDR_LEN, data_len,
			    skb->data + skb->len - CCMP_MIC_LEN,
			    skb->data + hdrlen + CCMP_HDR_LEN)) {
			printk(KERN_DEBUG "%s: CCMP decrypt failed for RX "
			       "frame from " MAC_FMT "\n", rx->dev->name,
			       MAC_ARG(rx->sta->addr));
			return TXRX_DROP;
		}
	}

	memcpy(key->u.ccmp.rx_pn[rx->u.rx.queue], pn, CCMP_PN_LEN);

	/* Remove CCMP header and MIC */
	skb_trim(skb, skb->len - CCMP_MIC_LEN);
	memmove(skb->data + CCMP_HDR_LEN, skb->data, hdrlen);
	skb_pull(skb, CCMP_HDR_LEN);

	return TXRX_CONTINUE;
}
Commit	Line	Data
f0706e82 JB	1	/*
	2	* Copyright 2002-2004, Instant802 Networks, Inc.
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 as
	6	* published by the Free Software Foundation.
	7	*/
	8
	9	#include <linux/netdevice.h>
	10	#include <linux/types.h>
	11	#include <linux/slab.h>
	12	#include <linux/skbuff.h>
	13	#include <linux/compiler.h>
	14	#include <net/iw_handler.h>
	15
	16	#include <net/mac80211.h>
	17	#include "ieee80211_common.h"
	18	#include "ieee80211_i.h"
	19	#include "michael.h"
	20	#include "tkip.h"
	21	#include "aes_ccm.h"
	22	#include "wpa.h"
	23
	24	static int ieee80211_get_hdr_info(const struct sk_buff skb, u8 sa, u8 *da,
	25	u8 qos_tid, u8 data, size_t data_len)
	26	{
	27	struct ieee80211_hdr *hdr;
	28	size_t hdrlen;
	29	u16 fc;
	30	int a4_included;
	31	u8 *pos;
	32
	33	hdr = (struct ieee80211_hdr *) skb->data;
	34	fc = le16_to_cpu(hdr->frame_control);
	35
	36	hdrlen = 24;
	37	if ((fc & (IEEE80211_FCTL_FROMDS \| IEEE80211_FCTL_TODS)) ==
	38	(IEEE80211_FCTL_FROMDS \| IEEE80211_FCTL_TODS)) {
	39	hdrlen += ETH_ALEN;
	40	*sa = hdr->addr4;
	41	*da = hdr->addr3;
	42	} else if (fc & IEEE80211_FCTL_FROMDS) {
	43	*sa = hdr->addr3;
	44	*da = hdr->addr1;
	45	} else if (fc & IEEE80211_FCTL_TODS) {
	46	*sa = hdr->addr2;
	47	*da = hdr->addr3;
	48	} else {
	49	*sa = hdr->addr2;
	50	*da = hdr->addr1;
	51	}
	52
	53	if (fc & 0x80)
	54	hdrlen += 2;
	55
	56	*data = skb->data + hdrlen;
	57	*data_len = skb->len - hdrlen;
	58
	59	a4_included = (fc & (IEEE80211_FCTL_TODS \| IEEE80211_FCTL_FROMDS)) ==
	60	(IEEE80211_FCTL_TODS \| IEEE80211_FCTL_FROMDS);
	61	if ((fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&
	62	fc & IEEE80211_STYPE_QOS_DATA) {
	63	pos = (u8 *) &hdr->addr4;
	64	if (a4_included)
65	pos += 6;
66	*qos_tid = pos[0] & 0x0f;
67	qos_tid \|= 0x80; / qos_included flag */
68	} else
69	*qos_tid = 0;
70
71	return skb->len < hdrlen ? -1 : 0;
72	}
73
74
75	ieee80211_txrx_result
76	ieee80211_tx_h_michael_mic_add(struct ieee80211_txrx_data *tx)
77	{
78	u8 data, sa, da, key, *mic, qos_tid;
79	size_t data_len;
80	u16 fc;
81	struct sk_buff *skb = tx->skb;
82	int authenticator;
83	int wpa_test = 0;
84
85	fc = tx->fc;
86
87	if (!tx->key \|\| tx->key->alg != ALG_TKIP \|\| skb->len < 24 \|\|
88	!WLAN_FC_DATA_PRESENT(fc))
89	return TXRX_CONTINUE;
90
91	if (ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len))
92	return TXRX_DROP;
93
94	if (!tx->key->force_sw_encrypt &&
95	!tx->fragmented &&
96	!(tx->local->hw.flags & IEEE80211_HW_TKIP_INCLUDE_MMIC) &&
97	!wpa_test) {
98	/* hwaccel - with no need for preallocated room for Michael MIC
99	*/
100	return TXRX_CONTINUE;
101	}
102
103	if (skb_tailroom(skb) < MICHAEL_MIC_LEN) {
104	I802_DEBUG_INC(tx->local->tx_expand_skb_head);
105	if (unlikely(pskb_expand_head(skb, TKIP_IV_LEN,
106	MICHAEL_MIC_LEN + TKIP_ICV_LEN,
107	GFP_ATOMIC))) {
108	printk(KERN_DEBUG "%s: failed to allocate more memory "
109	"for Michael MIC\n", tx->dev->name);
110	return TXRX_DROP;
111	}
112	}
113
114	#if 0
115	authenticator = fc & IEEE80211_FCTL_FROMDS; /* FIX */
116	#else
117	authenticator = 1;
118	#endif
119	key = &tx->key->key[authenticator ? ALG_TKIP_TEMP_AUTH_TX_MIC_KEY :
120	ALG_TKIP_TEMP_AUTH_RX_MIC_KEY];
121	mic = skb_put(skb, MICHAEL_MIC_LEN);
122	michael_mic(key, da, sa, qos_tid & 0x0f, data, data_len, mic);
123
124	return TXRX_CONTINUE;
125	}
126
127
128	ieee80211_txrx_result
129	ieee80211_rx_h_michael_mic_verify(struct ieee80211_txrx_data *rx)
130	{
131	u8 data, sa, da, key = NULL, qos_tid;
132	size_t data_len;
133	u16 fc;
134	u8 mic[MICHAEL_MIC_LEN];
135	struct sk_buff *skb = rx->skb;
136	int authenticator = 1, wpa_test = 0;
137
138	fc = rx->fc;
139
140	/* If device handles decryption totally, skip this check */
141	if ((rx->local->hw.flags & IEEE80211_HW_DEVICE_HIDES_WEP) \|\|
142	(rx->local->hw.flags & IEEE80211_HW_DEVICE_STRIPS_MIC))
143	return TXRX_CONTINUE;
144
145	if (!rx->key \|\| rx->key->alg != ALG_TKIP \|\|
146	!(rx->fc & IEEE80211_FCTL_PROTECTED) \|\| !WLAN_FC_DATA_PRESENT(fc))
147	return TXRX_CONTINUE;
148
149	if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&
150	!rx->key->force_sw_encrypt) {
151	if (rx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV) {
152	if (skb->len < MICHAEL_MIC_LEN)
153	return TXRX_DROP;
154	}
155	/* Need to verify Michael MIC sometimes in software even when
156	* hwaccel is used. Atheros ar5212: fragmented frames and QoS
157	* frames. */
158	if (!rx->fragmented && !wpa_test)
159	goto remove_mic;
160	}
161
162	if (ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len)
163	\|\| data_len < MICHAEL_MIC_LEN)
164	return TXRX_DROP;
165
166	data_len -= MICHAEL_MIC_LEN;
167
168	#if 0
169	authenticator = fc & IEEE80211_FCTL_TODS; /* FIX */
170	#else
171	authenticator = 1;
172	#endif
173	key = &rx->key->key[authenticator ? ALG_TKIP_TEMP_AUTH_RX_MIC_KEY :
174	ALG_TKIP_TEMP_AUTH_TX_MIC_KEY];
175	michael_mic(key, da, sa, qos_tid & 0x0f, data, data_len, mic);
176	if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0 \|\| wpa_test) {
177	if (!rx->u.rx.ra_match)
178	return TXRX_DROP;
179
180	printk(KERN_DEBUG "%s: invalid Michael MIC in data frame from "
181	MAC_FMT "\n", rx->dev->name, MAC_ARG(sa));
182
183	do {
184	struct ieee80211_hdr *hdr;
185	union iwreq_data wrqu;
186	char *buf = kmalloc(128, GFP_ATOMIC);
187	if (!buf)
188	break;
189
190	/* TODO: needed parameters: count, key type, TSC */
191	hdr = (struct ieee80211_hdr *) skb->data;
192	sprintf(buf, "MLME-MICHAELMICFAILURE.indication("
193	"keyid=%d %scast addr=" MAC_FMT ")",
194	rx->key->keyidx,
195	hdr->addr1[0] & 0x01 ? "broad" : "uni",
196	MAC_ARG(hdr->addr2));
197	memset(&wrqu, 0, sizeof(wrqu));
198	wrqu.data.length = strlen(buf);
199	wireless_send_event(rx->dev, IWEVCUSTOM, &wrqu, buf);
200	kfree(buf);
201	} while (0);
202
203	if (!rx->local->apdev)
204	return TXRX_DROP;
205
206	ieee80211_rx_mgmt(rx->local, rx->skb, rx->u.rx.status,
207	ieee80211_msg_michael_mic_failure);
208
209	return TXRX_QUEUED;
210	}
211
212	remove_mic:
213	/* remove Michael MIC from payload */
214	skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
215
216	return TXRX_CONTINUE;
217	}
218
219
220	static int tkip_encrypt_skb(struct ieee80211_txrx_data *tx,
221	struct sk_buff *skb, int test)
222	{
223	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) skb->data;
224	struct ieee80211_key *key = tx->key;
225	int hdrlen, len, tailneed;
226	u16 fc;
227	u8 *pos;
228
229	fc = le16_to_cpu(hdr->frame_control);
230	hdrlen = ieee80211_get_hdrlen(fc);
231	len = skb->len - hdrlen;
232
233	tailneed = !tx->key->force_sw_encrypt ? 0 : TKIP_ICV_LEN;
234	if ((skb_headroom(skb) < TKIP_IV_LEN \|\|
235	skb_tailroom(skb) < tailneed)) {
236	I802_DEBUG_INC(tx->local->tx_expand_skb_head);
237	if (unlikely(pskb_expand_head(skb, TKIP_IV_LEN, tailneed,
238	GFP_ATOMIC)))
239	return -1;
240	}
241
242	pos = skb_push(skb, TKIP_IV_LEN);
243	memmove(pos, pos + TKIP_IV_LEN, hdrlen);
244	pos += hdrlen;
245
246	/* Increase IV for the frame */
247	key->u.tkip.iv16++;
248	if (key->u.tkip.iv16 == 0)
249	key->u.tkip.iv32++;
250
251	if (!tx->key->force_sw_encrypt) {
252	u32 flags = tx->local->hw.flags;
253	hdr = (struct ieee80211_hdr *)skb->data;
254
255	/* hwaccel - with preallocated room for IV */
256	ieee80211_tkip_add_iv(pos, key,
257	(u8) (key->u.tkip.iv16 >> 8),
258	(u8) (((key->u.tkip.iv16 >> 8) \| 0x20) &
259	0x7f),
260	(u8) key->u.tkip.iv16);
261
262	if (flags & IEEE80211_HW_TKIP_REQ_PHASE2_KEY)
263	ieee80211_tkip_gen_rc4key(key, hdr->addr2,
264	tx->u.tx.control->tkip_key);
265	else if (flags & IEEE80211_HW_TKIP_REQ_PHASE1_KEY) {
266	if (key->u.tkip.iv16 == 0 \|\|
267	!key->u.tkip.tx_initialized) {
268	ieee80211_tkip_gen_phase1key(key, hdr->addr2,
269	(u16 *)tx->u.tx.control->tkip_key);
270	key->u.tkip.tx_initialized = 1;
271	tx->u.tx.control->flags \|=
272	IEEE80211_TXCTL_TKIP_NEW_PHASE1_KEY;
273	} else
274	tx->u.tx.control->flags &=
275	~IEEE80211_TXCTL_TKIP_NEW_PHASE1_KEY;
276	}
277
278	tx->u.tx.control->key_idx = tx->key->hw_key_idx;
279	return 0;
280	}
281
282	/* Add room for ICV */
283	skb_put(skb, TKIP_ICV_LEN);
284
285	hdr = (struct ieee80211_hdr *) skb->data;
286	ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
287	key, pos, len, hdr->addr2);
288	return 0;
289	}
290
291
292	ieee80211_txrx_result
293	ieee80211_tx_h_tkip_encrypt(struct ieee80211_txrx_data *tx)
294	{
295	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) tx->skb->data;
296	u16 fc;
297	struct ieee80211_key *key = tx->key;
298	struct sk_buff *skb = tx->skb;
299	int wpa_test = 0, test = 0;
300
301	fc = le16_to_cpu(hdr->frame_control);
302
303	if (!key \|\| key->alg != ALG_TKIP \|\| !WLAN_FC_DATA_PRESENT(fc))
304	return TXRX_CONTINUE;
305
306	tx->u.tx.control->icv_len = TKIP_ICV_LEN;
307	tx->u.tx.control->iv_len = TKIP_IV_LEN;
308	ieee80211_tx_set_iswep(tx);
309
310	if (!tx->key->force_sw_encrypt &&
311	!(tx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV) &&
312	!wpa_test) {
313	/* hwaccel - with no need for preallocated room for IV/ICV */
314	tx->u.tx.control->key_idx = tx->key->hw_key_idx;
315	return TXRX_CONTINUE;
316	}
317
318	if (tkip_encrypt_skb(tx, skb, test) < 0)
319	return TXRX_DROP;
320
321	if (tx->u.tx.extra_frag) {
322	int i;
323	for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
324	if (tkip_encrypt_skb(tx, tx->u.tx.extra_frag[i], test)
325	< 0)
326	return TXRX_DROP;
327	}
328	}
329
330	return TXRX_CONTINUE;
331	}
332
333
334	ieee80211_txrx_result
335	ieee80211_rx_h_tkip_decrypt(struct ieee80211_txrx_data *rx)
336	{
337	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) rx->skb->data;
338	u16 fc;
339	int hdrlen, res, hwaccel = 0, wpa_test = 0;
340	struct ieee80211_key *key = rx->key;
341	struct sk_buff *skb = rx->skb;
342
343	fc = le16_to_cpu(hdr->frame_control);
344	hdrlen = ieee80211_get_hdrlen(fc);
345
346	if (!rx->key \|\| rx->key->alg != ALG_TKIP \|\|
347	!(rx->fc & IEEE80211_FCTL_PROTECTED) \|\|
348	(rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
349	return TXRX_CONTINUE;
350
351	if (!rx->sta \|\| skb->len - hdrlen < 12)
352	return TXRX_DROP;
353
354	if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&
355	!rx->key->force_sw_encrypt) {
356	if (!(rx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV)) {
357	/* Hardware takes care of all processing, including
358	* replay protection, so no need to continue here. */
359	return TXRX_CONTINUE;
360	}
361
362	/* let TKIP code verify IV, but skip decryption */
363	hwaccel = 1;
364	}
365
366	res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,
367	key, skb->data + hdrlen,
368	skb->len - hdrlen, rx->sta->addr,
369	hwaccel, rx->u.rx.queue);
370	if (res != TKIP_DECRYPT_OK \|\| wpa_test) {
371	printk(KERN_DEBUG "%s: TKIP decrypt failed for RX frame from "
372	MAC_FMT " (res=%d)\n",
373	rx->dev->name, MAC_ARG(rx->sta->addr), res);
374	return TXRX_DROP;
375	}
376
377	/* Trim ICV */
378	skb_trim(skb, skb->len - TKIP_ICV_LEN);
379
380	/* Remove IV */
381	memmove(skb->data + TKIP_IV_LEN, skb->data, hdrlen);
382	skb_pull(skb, TKIP_IV_LEN);
383
384	return TXRX_CONTINUE;
385	}
386
387
388	static void ccmp_special_blocks(struct sk_buff skb, u8 pn, u8 b_0, u8 aad,
389	int encrypted)
390	{
391	u16 fc;
392	int a4_included, qos_included;
393	u8 qos_tid, fc_pos, data, sa, da;
394	int len_a;
395	size_t data_len;
396	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) skb->data;
397
398	fc_pos = (u8 *) &hdr->frame_control;
399	fc = fc_pos[0] ^ (fc_pos[1] << 8);
400	a4_included = (fc & (IEEE80211_FCTL_TODS \| IEEE80211_FCTL_FROMDS)) ==
401	(IEEE80211_FCTL_TODS \| IEEE80211_FCTL_FROMDS);
402
403	ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len);
404	data_len -= CCMP_HDR_LEN + (encrypted ? CCMP_MIC_LEN : 0);
405	if (qos_tid & 0x80) {
406	qos_included = 1;
407	qos_tid &= 0x0f;
408	} else
409	qos_included = 0;
410	/* First block, b_0 */
411
412	b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */
413	/* Nonce: QoS Priority \| A2 \| PN */
414	b_0[1] = qos_tid;
415	memcpy(&b_0[2], hdr->addr2, 6);
416	memcpy(&b_0[8], pn, CCMP_PN_LEN);
417	/* l(m) */
418	b_0[14] = (data_len >> 8) & 0xff;
419	b_0[15] = data_len & 0xff;
420
421
422	/* AAD (extra authenticate-only data) / masked 802.11 header
423	* FC \| A1 \| A2 \| A3 \| SC \| [A4] \| [QC] */
424
425	len_a = a4_included ? 28 : 22;
426	if (qos_included)
427	len_a += 2;
428
429	aad[0] = 0; /* (len_a >> 8) & 0xff; */
430	aad[1] = len_a & 0xff;
431	/* Mask FC: zero subtype b4 b5 b6 */
432	aad[2] = fc_pos[0] & ~(BIT(4) \| BIT(5) \| BIT(6));
433	/* Retry, PwrMgt, MoreData; set Protected */
434	aad[3] = (fc_pos[1] & ~(BIT(3) \| BIT(4) \| BIT(5))) \| BIT(6);
435	memcpy(&aad[4], &hdr->addr1, 18);
436
437	/* Mask Seq#, leave Frag# */
438	aad[22] = ((u8 ) &hdr->seq_ctrl) & 0x0f;
439	aad[23] = 0;
440	if (a4_included) {
441	memcpy(&aad[24], hdr->addr4, 6);
442	aad[30] = 0;
443	aad[31] = 0;
444	} else
445	memset(&aad[24], 0, 8);
446	if (qos_included) {
447	u8 *dpos = &aad[a4_included ? 30 : 24];
448
449	/* Mask QoS Control field */
450	dpos[0] = qos_tid;
451	dpos[1] = 0;
452	}
453	}
454
455
456	static inline void ccmp_pn2hdr(u8 hdr, u8 pn, int key_id)
457	{
458	hdr[0] = pn[5];
459	hdr[1] = pn[4];
460	hdr[2] = 0;
461	hdr[3] = 0x20 \| (key_id << 6);
462	hdr[4] = pn[3];
463	hdr[5] = pn[2];
464	hdr[6] = pn[1];
465	hdr[7] = pn[0];
466	}
467
468
469	static inline int ccmp_hdr2pn(u8 pn, u8 hdr)
470	{
471	pn[0] = hdr[7];
472	pn[1] = hdr[6];
473	pn[2] = hdr[5];
474	pn[3] = hdr[4];
475	pn[4] = hdr[1];
476	pn[5] = hdr[0];
477	return (hdr[3] >> 6) & 0x03;
478	}
479
480
481	static int ccmp_encrypt_skb(struct ieee80211_txrx_data *tx,
482	struct sk_buff *skb, int test)
483	{
484	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) skb->data;
485	struct ieee80211_key *key = tx->key;
486	int hdrlen, len, tailneed;
487	u16 fc;
488	u8 pos, pn, b_0, aad, *scratch;
489	int i;
490
491	scratch = key->u.ccmp.tx_crypto_buf;
492	b_0 = scratch + 3 * AES_BLOCK_LEN;
493	aad = scratch + 4 * AES_BLOCK_LEN;
494
495	fc = le16_to_cpu(hdr->frame_control);
496	hdrlen = ieee80211_get_hdrlen(fc);
497	len = skb->len - hdrlen;
498
499	tailneed = !key->force_sw_encrypt ? 0 : CCMP_MIC_LEN;
500
501	if ((skb_headroom(skb) < CCMP_HDR_LEN \|\|
502	skb_tailroom(skb) < tailneed)) {
503	I802_DEBUG_INC(tx->local->tx_expand_skb_head);
504	if (unlikely(pskb_expand_head(skb, CCMP_HDR_LEN, tailneed,
505	GFP_ATOMIC)))
506	return -1;
507	}
508
509	pos = skb_push(skb, CCMP_HDR_LEN);
510	memmove(pos, pos + CCMP_HDR_LEN, hdrlen);
511	hdr = (struct ieee80211_hdr *) pos;
512	pos += hdrlen;
513
514	/* PN = PN + 1 */
515	pn = key->u.ccmp.tx_pn;
516
517	for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
518	pn[i]++;
519	if (pn[i])
520	break;
521	}
522
523	ccmp_pn2hdr(pos, pn, key->keyidx);
524
525	if (!key->force_sw_encrypt) {
526	/* hwaccel - with preallocated room for CCMP header */
527	tx->u.tx.control->key_idx = key->hw_key_idx;
528	return 0;
529	}
530
531	pos += CCMP_HDR_LEN;
532	ccmp_special_blocks(skb, pn, b_0, aad, 0);
533	ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, scratch, b_0, aad, pos, len,
534	pos, skb_put(skb, CCMP_MIC_LEN));
535
536	return 0;
537	}
538
539
540	ieee80211_txrx_result
541	ieee80211_tx_h_ccmp_encrypt(struct ieee80211_txrx_data *tx)
542	{
543	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) tx->skb->data;
544	struct ieee80211_key *key = tx->key;
545	u16 fc;
546	struct sk_buff *skb = tx->skb;
547	int test = 0;
548
549	fc = le16_to_cpu(hdr->frame_control);
550
551	if (!key \|\| key->alg != ALG_CCMP \|\| !WLAN_FC_DATA_PRESENT(fc))
552	return TXRX_CONTINUE;
553
554	tx->u.tx.control->icv_len = CCMP_MIC_LEN;
555	tx->u.tx.control->iv_len = CCMP_HDR_LEN;
556	ieee80211_tx_set_iswep(tx);
557
558	if (!tx->key->force_sw_encrypt &&
559	!(tx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV)) {
560	/* hwaccel - with no need for preallocated room for CCMP "
561	* header or MIC fields */
562	tx->u.tx.control->key_idx = tx->key->hw_key_idx;
563	return TXRX_CONTINUE;
564	}
565
566	if (ccmp_encrypt_skb(tx, skb, test) < 0)
567	return TXRX_DROP;
568
569	if (tx->u.tx.extra_frag) {
570	int i;
571
572	for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
573	if (ccmp_encrypt_skb(tx, tx->u.tx.extra_frag[i], test)
574	< 0)
575	return TXRX_DROP;
576	}
577	}
578
579	return TXRX_CONTINUE;
580	}
581
582
583	ieee80211_txrx_result
584	ieee80211_rx_h_ccmp_decrypt(struct ieee80211_txrx_data *rx)
585	{
586	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) rx->skb->data;
587	u16 fc;
588	int hdrlen;
589	struct ieee80211_key *key = rx->key;
590	struct sk_buff *skb = rx->skb;
591	u8 pn[CCMP_PN_LEN];
592	int data_len;
593
594	fc = le16_to_cpu(hdr->frame_control);
595	hdrlen = ieee80211_get_hdrlen(fc);
596
597	if (!key \|\| key->alg != ALG_CCMP \|\|
598	!(rx->fc & IEEE80211_FCTL_PROTECTED) \|\|
599	(rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)
600	return TXRX_CONTINUE;
601
602	data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN;
603	if (!rx->sta \|\| data_len < 0)
604	return TXRX_DROP;
605
606	if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&
607	!key->force_sw_encrypt &&
608	!(rx->local->hw.flags & IEEE80211_HW_WEP_INCLUDE_IV))
609	return TXRX_CONTINUE;
610
611	(void) ccmp_hdr2pn(pn, skb->data + hdrlen);
612
613	if (memcmp(pn, key->u.ccmp.rx_pn[rx->u.rx.queue], CCMP_PN_LEN) <= 0) {
614	#ifdef CONFIG_MAC80211_DEBUG
615	u8 *ppn = key->u.ccmp.rx_pn[rx->u.rx.queue];
616	printk(KERN_DEBUG "%s: CCMP replay detected for RX frame from "
617	MAC_FMT " (RX PN %02x%02x%02x%02x%02x%02x <= prev. PN "
618	"%02x%02x%02x%02x%02x%02x)\n", rx->dev->name,
619	MAC_ARG(rx->sta->addr),
620	pn[0], pn[1], pn[2], pn[3], pn[4], pn[5],
621	ppn[0], ppn[1], ppn[2], ppn[3], ppn[4], ppn[5]);
622	#endif /* CONFIG_MAC80211_DEBUG */
623	key->u.ccmp.replays++;
624	return TXRX_DROP;
625	}
626
627	if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&
628	!key->force_sw_encrypt) {
629	/* hwaccel has already decrypted frame and verified MIC */
630	} else {
631	u8 scratch, b_0, *aad;
632
633	scratch = key->u.ccmp.rx_crypto_buf;
634	b_0 = scratch + 3 * AES_BLOCK_LEN;
635	aad = scratch + 4 * AES_BLOCK_LEN;
636
637	ccmp_special_blocks(skb, pn, b_0, aad, 1);
638
639	if (ieee80211_aes_ccm_decrypt(
640	key->u.ccmp.tfm, scratch, b_0, aad,
641	skb->data + hdrlen + CCMP_HDR_LEN, data_len,
642	skb->data + skb->len - CCMP_MIC_LEN,
643	skb->data + hdrlen + CCMP_HDR_LEN)) {
644	printk(KERN_DEBUG "%s: CCMP decrypt failed for RX "
645	"frame from " MAC_FMT "\n", rx->dev->name,
646	MAC_ARG(rx->sta->addr));
647	return TXRX_DROP;
648	}
649	}
650
651	memcpy(key->u.ccmp.rx_pn[rx->u.rx.queue], pn, CCMP_PN_LEN);
652
653	/* Remove CCMP header and MIC */
654	skb_trim(skb, skb->len - CCMP_MIC_LEN);
655	memmove(skb->data + CCMP_HDR_LEN, skb->data, hdrlen);
656	skb_pull(skb, CCMP_HDR_LEN);
657
658	return TXRX_CONTINUE;
659	}
660