[deliverable/linux.git] / drivers / staging / rtl8187se / ieee80211 / ieee80211_crypt_ccmp.c

/*
 * Host AP crypt: host-based CCMP encryption implementation for Host AP driver
 *
 * Copyright (c) 2003-2004, Jouni Malinen <jkmaline@cc.hut.fi>
 *
 * 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. See README and COPYING for
 * more details.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/random.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/if_ether.h>
#include <linux/if_arp.h>
#include <linux/string.h>
#include <linux/wireless.h>

#include "ieee80211.h"

#include <linux/crypto.h>
#include <linux/scatterlist.h>

MODULE_AUTHOR("Jouni Malinen");
MODULE_DESCRIPTION("Host AP crypt: CCMP");
MODULE_LICENSE("GPL");


#define AES_BLOCK_LEN 16
#define CCMP_HDR_LEN 8
#define CCMP_MIC_LEN 8
#define CCMP_TK_LEN 16
#define CCMP_PN_LEN 6

struct ieee80211_ccmp_data {
	u8 key[CCMP_TK_LEN];
	int key_set;

	u8 tx_pn[CCMP_PN_LEN];
	u8 rx_pn[CCMP_PN_LEN];

	u32 dot11RSNAStatsCCMPFormatErrors;
	u32 dot11RSNAStatsCCMPReplays;
	u32 dot11RSNAStatsCCMPDecryptErrors;

	int key_idx;

	struct crypto_tfm *tfm;

	/* scratch buffers for virt_to_page() (crypto API) */
	u8 tx_b0[AES_BLOCK_LEN], tx_b[AES_BLOCK_LEN],
		tx_e[AES_BLOCK_LEN], tx_s0[AES_BLOCK_LEN];
	u8 rx_b0[AES_BLOCK_LEN], rx_b[AES_BLOCK_LEN], rx_a[AES_BLOCK_LEN];
};

void ieee80211_ccmp_aes_encrypt(struct crypto_tfm *tfm,
				const u8 pt[16], u8 ct[16])
{
	crypto_cipher_encrypt_one((void *)tfm, ct, pt);
}

static void *ieee80211_ccmp_init(int key_idx)
{
	struct ieee80211_ccmp_data *priv;

	priv = kzalloc(sizeof(*priv), GFP_ATOMIC);
	if (priv == NULL)
		goto fail;
	priv->key_idx = key_idx;

	priv->tfm = (void *)crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC);
	if (IS_ERR(priv->tfm)) {
		pr_debug("could not allocate crypto API aes\n");
		priv->tfm = NULL;
		goto fail;
	}

	return priv;

fail:
	if (priv) {
		if (priv->tfm)
			crypto_free_cipher((void *)priv->tfm);
		kfree(priv);
	}

	return NULL;
}


static void ieee80211_ccmp_deinit(void *priv)
{
	struct ieee80211_ccmp_data *_priv = priv;

	if (_priv && _priv->tfm)
		crypto_free_cipher((void *)_priv->tfm);
	kfree(priv);
}


static inline void xor_block(u8 *b, u8 *a, size_t len)
{
	int i;
	for (i = 0; i < len; i++)
		b[i] ^= a[i];
}

static void ccmp_init_blocks(struct crypto_tfm *tfm,
			     struct ieee80211_hdr_4addr *hdr,
			     u8 *pn, size_t dlen, u8 *b0, u8 *auth,
			     u8 *s0)
{
	u8 *pos, qc = 0;
	size_t aad_len;
	u16 fc;
	int a4_included, qc_included;
	u8 aad[2 * AES_BLOCK_LEN];

	fc = le16_to_cpu(hdr->frame_ctl);
	a4_included = ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
		       (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS));
	/*
	qc_included = ((WLAN_FC_GET_TYPE(fc) == IEEE80211_FTYPE_DATA) &&
		       (WLAN_FC_GET_STYPE(fc) & 0x08));
	*/
	qc_included = ((WLAN_FC_GET_TYPE(fc) == IEEE80211_FTYPE_DATA) &&
		       (WLAN_FC_GET_STYPE(fc) & 0x80));
	aad_len = 22;
	if (a4_included)
		aad_len += 6;
	if (qc_included) {
		pos = (u8 *) &hdr->addr4;
		if (a4_included)
			pos += 6;
		qc = *pos & 0x0f;
		aad_len += 2;
	}
	/* CCM Initial Block:
	 * Flag (Include authentication header, M=3 (8-octet MIC),
	 *       L=1 (2-octet Dlen))
	 * Nonce: 0x00 | A2 | PN
	 * Dlen */
	b0[0] = 0x59;
	b0[1] = qc;
	memcpy(b0 + 2, hdr->addr2, ETH_ALEN);
	memcpy(b0 + 8, pn, CCMP_PN_LEN);
	b0[14] = (dlen >> 8) & 0xff;
	b0[15] = dlen & 0xff;

	/* AAD:
	 * FC with bits 4..6 and 11..13 masked to zero; 14 is always one
	 * A1 | A2 | A3
	 * SC with bits 4..15 (seq#) masked to zero
	 * A4 (if present)
	 * QC (if present)
	 */
	pos = (u8 *) hdr;
	aad[0] = 0; /* aad_len >> 8 */
	aad[1] = aad_len & 0xff;
	aad[2] = pos[0] & 0x8f;
	aad[3] = pos[1] & 0xc7;
	memcpy(aad + 4, hdr->addr1, 3 * ETH_ALEN);
	pos = (u8 *) &hdr->seq_ctl;
	aad[22] = pos[0] & 0x0f;
	aad[23] = 0; /* all bits masked */
	memset(aad + 24, 0, 8);
	if (a4_included)
		memcpy(aad + 24, hdr->addr4, ETH_ALEN);
	if (qc_included) {
		aad[a4_included ? 30 : 24] = qc;
		/* rest of QC masked */
	}

	/* Start with the first block and AAD */
	ieee80211_ccmp_aes_encrypt(tfm, b0, auth);
	xor_block(auth, aad, AES_BLOCK_LEN);
	ieee80211_ccmp_aes_encrypt(tfm, auth, auth);
	xor_block(auth, &aad[AES_BLOCK_LEN], AES_BLOCK_LEN);
	ieee80211_ccmp_aes_encrypt(tfm, auth, auth);
	b0[0] &= 0x07;
	b0[14] = b0[15] = 0;
	ieee80211_ccmp_aes_encrypt(tfm, b0, s0);
}

static int ieee80211_ccmp_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
{
	struct ieee80211_ccmp_data *key = priv;
	int data_len, i;
	u8 *pos;
	struct ieee80211_hdr_4addr *hdr;
	int blocks, last, len;
	u8 *mic;
	u8 *b0 = key->tx_b0;
	u8 *b = key->tx_b;
	u8 *e = key->tx_e;
	u8 *s0 = key->tx_s0;

	if (skb_headroom(skb) < CCMP_HDR_LEN ||
	    skb_tailroom(skb) < CCMP_MIC_LEN ||
	    skb->len < hdr_len)
		return -1;

	data_len = skb->len - hdr_len;
	pos = skb_push(skb, CCMP_HDR_LEN);
	memmove(pos, pos + CCMP_HDR_LEN, hdr_len);
	pos += hdr_len;

	i = CCMP_PN_LEN - 1;
	while (i >= 0) {
		key->tx_pn[i]++;
		if (key->tx_pn[i] != 0)
			break;
		i--;
	}

	*pos++ = key->tx_pn[5];
	*pos++ = key->tx_pn[4];
	*pos++ = 0;
	*pos++ = (key->key_idx << 6) | (1 << 5) /* Ext IV included */;
	*pos++ = key->tx_pn[3];
	*pos++ = key->tx_pn[2];
	*pos++ = key->tx_pn[1];
	*pos++ = key->tx_pn[0];

	hdr = (struct ieee80211_hdr_4addr *)skb->data;
	mic = skb_put(skb, CCMP_MIC_LEN);

	ccmp_init_blocks(key->tfm, hdr, key->tx_pn, data_len, b0, b, s0);

	blocks = (data_len + AES_BLOCK_LEN - 1) / AES_BLOCK_LEN;
	last = data_len % AES_BLOCK_LEN;

	for (i = 1; i <= blocks; i++) {
		len = (i == blocks && last) ? last : AES_BLOCK_LEN;
		/* Authentication */
		xor_block(b, pos, len);
		ieee80211_ccmp_aes_encrypt(key->tfm, b, b);
		/* Encryption, with counter */
		b0[14] = (i >> 8) & 0xff;
		b0[15] = i & 0xff;
		ieee80211_ccmp_aes_encrypt(key->tfm, b0, e);
		xor_block(pos, e, len);
		pos += len;
	}

	for (i = 0; i < CCMP_MIC_LEN; i++)
		mic[i] = b[i] ^ s0[i];

	return 0;
}


static int ieee80211_ccmp_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
{
	struct ieee80211_ccmp_data *key = priv;
	u8 keyidx, *pos;
	struct ieee80211_hdr_4addr *hdr;
	u8 pn[6];
	size_t data_len = skb->len - hdr_len - CCMP_HDR_LEN - CCMP_MIC_LEN;
	u8 *mic = skb->data + skb->len - CCMP_MIC_LEN;
	u8 *b0 = key->rx_b0;
	u8 *b = key->rx_b;
	u8 *a = key->rx_a;
	int i, blocks, last, len;

	if (skb->len < hdr_len + CCMP_HDR_LEN + CCMP_MIC_LEN) {
		key->dot11RSNAStatsCCMPFormatErrors++;
		return -1;
	}

	hdr = (struct ieee80211_hdr_4addr *)skb->data;
	pos = skb->data + hdr_len;
	keyidx = pos[3];
	if (!(keyidx & (1 << 5))) {
		if (net_ratelimit()) {
			pr_debug("received packet without ExtIV flag from %pM\n",
				 hdr->addr2);
		}
		key->dot11RSNAStatsCCMPFormatErrors++;
		return -2;
	}
	keyidx >>= 6;
	if (key->key_idx != keyidx) {
		pr_debug("RX tkey->key_idx=%d frame keyidx=%d priv=%p\n",
			 key->key_idx, keyidx, priv);
		return -6;
	}
	if (!key->key_set) {
		if (net_ratelimit()) {
			pr_debug("received packet from %pM with keyid=%d that does not have a configured key\n",
				 hdr->addr2, keyidx);
		}
		return -3;
	}

	pn[0] = pos[7];
	pn[1] = pos[6];
	pn[2] = pos[5];
	pn[3] = pos[4];
	pn[4] = pos[1];
	pn[5] = pos[0];
	pos += 8;

	if (memcmp(pn, key->rx_pn, CCMP_PN_LEN) <= 0) {
		if (net_ratelimit()) {
			pr_debug("replay detected: STA=%pM previous PN %pm received PN %pm\n",
				 hdr->addr2, key->rx_pn, pn);
		}
		key->dot11RSNAStatsCCMPReplays++;
		return -4;
	}

	ccmp_init_blocks(key->tfm, hdr, pn, data_len, b0, a, b);
	xor_block(mic, b, CCMP_MIC_LEN);

	blocks = (data_len + AES_BLOCK_LEN - 1) / AES_BLOCK_LEN;
	last = data_len % AES_BLOCK_LEN;

	for (i = 1; i <= blocks; i++) {
		len = (i == blocks && last) ? last : AES_BLOCK_LEN;
		/* Decrypt, with counter */
		b0[14] = (i >> 8) & 0xff;
		b0[15] = i & 0xff;
		ieee80211_ccmp_aes_encrypt(key->tfm, b0, b);
		xor_block(pos, b, len);
		/* Authentication */
		xor_block(a, pos, len);
		ieee80211_ccmp_aes_encrypt(key->tfm, a, a);
		pos += len;
	}

	if (memcmp(mic, a, CCMP_MIC_LEN) != 0) {
		if (net_ratelimit())
			pr_debug("decrypt failed: STA=%pM\n", hdr->addr2);

		key->dot11RSNAStatsCCMPDecryptErrors++;
		return -5;
	}

	memcpy(key->rx_pn, pn, CCMP_PN_LEN);

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

	return keyidx;
}


static int ieee80211_ccmp_set_key(void *key, int len, u8 *seq, void *priv)
{
	struct ieee80211_ccmp_data *data = priv;
	int keyidx;
	struct crypto_tfm *tfm = data->tfm;

	keyidx = data->key_idx;
	memset(data, 0, sizeof(*data));
	data->key_idx = keyidx;
	data->tfm = tfm;
	if (len == CCMP_TK_LEN) {
		memcpy(data->key, key, CCMP_TK_LEN);
		data->key_set = 1;
		if (seq) {
			data->rx_pn[0] = seq[5];
			data->rx_pn[1] = seq[4];
			data->rx_pn[2] = seq[3];
			data->rx_pn[3] = seq[2];
			data->rx_pn[4] = seq[1];
			data->rx_pn[5] = seq[0];
		}
		crypto_cipher_setkey((void *)data->tfm, data->key, CCMP_TK_LEN);
	} else if (len == 0)
		data->key_set = 0;
	else
		return -1;

	return 0;
}


static int ieee80211_ccmp_get_key(void *key, int len, u8 *seq, void *priv)
{
	struct ieee80211_ccmp_data *data = priv;

	if (len < CCMP_TK_LEN)
		return -1;

	if (!data->key_set)
		return 0;
	memcpy(key, data->key, CCMP_TK_LEN);

	if (seq) {
		seq[0] = data->tx_pn[5];
		seq[1] = data->tx_pn[4];
		seq[2] = data->tx_pn[3];
		seq[3] = data->tx_pn[2];
		seq[4] = data->tx_pn[1];
		seq[5] = data->tx_pn[0];
	}

	return CCMP_TK_LEN;
}


static char *ieee80211_ccmp_print_stats(char *p, void *priv)
{
	struct ieee80211_ccmp_data *ccmp = priv;
	p += sprintf(p,
		     "key[%d] alg=CCMP key_set=%d tx_pn=%pm rx_pn=%pm format_errors=%d replays=%d decrypt_errors=%d\n",
		     ccmp->key_idx, ccmp->key_set,
		     ccmp->tx_pn, ccmp->rx_pn,
		     ccmp->dot11RSNAStatsCCMPFormatErrors,
		     ccmp->dot11RSNAStatsCCMPReplays,
		     ccmp->dot11RSNAStatsCCMPDecryptErrors);

	return p;
}

void ieee80211_ccmp_null(void)
{
	return;
}
static struct ieee80211_crypto_ops ieee80211_crypt_ccmp = {
	.name			= "CCMP",
	.init			= ieee80211_ccmp_init,
	.deinit			= ieee80211_ccmp_deinit,
	.encrypt_mpdu		= ieee80211_ccmp_encrypt,
	.decrypt_mpdu		= ieee80211_ccmp_decrypt,
	.encrypt_msdu		= NULL,
	.decrypt_msdu		= NULL,
	.set_key		= ieee80211_ccmp_set_key,
	.get_key		= ieee80211_ccmp_get_key,
	.print_stats		= ieee80211_ccmp_print_stats,
	.extra_prefix_len	= CCMP_HDR_LEN,
	.extra_postfix_len	= CCMP_MIC_LEN,
	.owner			= THIS_MODULE,
};


int ieee80211_crypto_ccmp_init(void)
{
	return ieee80211_register_crypto_ops(&ieee80211_crypt_ccmp);
}


void ieee80211_crypto_ccmp_exit(void)
{
	ieee80211_unregister_crypto_ops(&ieee80211_crypt_ccmp);
}
Commit	Line	Data
c8d86be3 GKH	1	/*
	2	* Host AP crypt: host-based CCMP encryption implementation for Host AP driver
	3	*
	4	* Copyright (c) 2003-2004, Jouni Malinen <jkmaline@cc.hut.fi>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License version 2 as
	8	* published by the Free Software Foundation. See README and COPYING for
	9	* more details.
	10	*/
	11
d6f272c2 YT	12	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
d6f272c2 YT	13
c8d86be3	14	#include <linux/module.h>
c8d86be3 GKH	15	#include <linux/slab.h>
	16	#include <linux/random.h>
	17	#include <linux/skbuff.h>
	18	#include <linux/netdevice.h>
	19	#include <linux/if_ether.h>
	20	#include <linux/if_arp.h>
8433b143	21	#include <linux/string.h>
c8d86be3 GKH	22	#include <linux/wireless.h>
	23
	24	#include "ieee80211.h"
	25
c8d86be3	26	#include <linux/crypto.h>
0370453f	27	#include <linux/scatterlist.h>
c8d86be3 GKH	28
	29	MODULE_AUTHOR("Jouni Malinen");
	30	MODULE_DESCRIPTION("Host AP crypt: CCMP");
	31	MODULE_LICENSE("GPL");
	32
c8d86be3 GKH	33
	34	#define AES_BLOCK_LEN 16
	35	#define CCMP_HDR_LEN 8
	36	#define CCMP_MIC_LEN 8
	37	#define CCMP_TK_LEN 16
	38	#define CCMP_PN_LEN 6
	39
	40	struct ieee80211_ccmp_data {
	41	u8 key[CCMP_TK_LEN];
	42	int key_set;
	43
	44	u8 tx_pn[CCMP_PN_LEN];
	45	u8 rx_pn[CCMP_PN_LEN];
	46
	47	u32 dot11RSNAStatsCCMPFormatErrors;
	48	u32 dot11RSNAStatsCCMPReplays;
	49	u32 dot11RSNAStatsCCMPDecryptErrors;
	50
	51	int key_idx;
	52
	53	struct crypto_tfm *tfm;
	54
	55	/* scratch buffers for virt_to_page() (crypto API) */
	56	u8 tx_b0[AES_BLOCK_LEN], tx_b[AES_BLOCK_LEN],
	57	tx_e[AES_BLOCK_LEN], tx_s0[AES_BLOCK_LEN];
	58	u8 rx_b0[AES_BLOCK_LEN], rx_b[AES_BLOCK_LEN], rx_a[AES_BLOCK_LEN];
	59	};
	60
	61	void ieee80211_ccmp_aes_encrypt(struct crypto_tfm *tfm,
5cfa1b25	62	const u8 pt[16], u8 ct[16])
c8d86be3	63	{
c8d86be3	64	crypto_cipher_encrypt_one((void *)tfm, ct, pt);
c8d86be3 GKH	65	}
c8d86be3 GKH	66
5bd6e9e0	67	static void *ieee80211_ccmp_init(int key_idx)
c8d86be3 GKH	68	{
	69	struct ieee80211_ccmp_data *priv;
	70
7a6cb0d5	71	priv = kzalloc(sizeof(*priv), GFP_ATOMIC);
c8d86be3 GKH	72	if (priv == NULL)
c8d86be3 GKH	73	goto fail;
c8d86be3 GKH	74	priv->key_idx = key_idx;
c8d86be3 GKH	75
0370453f	76	priv->tfm = (void *)crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC);
c8d86be3	77	if (IS_ERR(priv->tfm)) {
d6f272c2	78	pr_debug("could not allocate crypto API aes\n");
c8d86be3 GKH	79	priv->tfm = NULL;
	80	goto fail;
	81	}
0370453f	82
c8d86be3 GKH	83	return priv;
	84
	85	fail:
	86	if (priv) {
	87	if (priv->tfm)
c8d86be3	88	crypto_free_cipher((void *)priv->tfm);
c8d86be3 GKH	89	kfree(priv);
	90	}
	91
	92	return NULL;
	93	}
	94
	95
	96	static void ieee80211_ccmp_deinit(void *priv)
	97	{
	98	struct ieee80211_ccmp_data *_priv = priv;
0370453f	99
c8d86be3	100	if (_priv && _priv->tfm)
c8d86be3	101	crypto_free_cipher((void *)_priv->tfm);
c8d86be3 GKH	102	kfree(priv);
	103	}
	104
	105
	106	static inline void xor_block(u8 b, u8 a, size_t len)
	107	{
	108	int i;
	109	for (i = 0; i < len; i++)
	110	b[i] ^= a[i];
	111	}
	112
c8d86be3	113	static void ccmp_init_blocks(struct crypto_tfm *tfm,
0604384d	114	struct ieee80211_hdr_4addr *hdr,
c8d86be3 GKH	115	u8 pn, size_t dlen, u8 b0, u8 *auth,
	116	u8 *s0)
	117	{
	118	u8 *pos, qc = 0;
	119	size_t aad_len;
	120	u16 fc;
	121	int a4_included, qc_included;
	122	u8 aad[2 * AES_BLOCK_LEN];
	123
	124	fc = le16_to_cpu(hdr->frame_ctl);
	125	a4_included = ((fc & (IEEE80211_FCTL_TODS \| IEEE80211_FCTL_FROMDS)) ==
	126	(IEEE80211_FCTL_TODS \| IEEE80211_FCTL_FROMDS));
	127	/*
	128	qc_included = ((WLAN_FC_GET_TYPE(fc) == IEEE80211_FTYPE_DATA) &&
	129	(WLAN_FC_GET_STYPE(fc) & 0x08));
937afb70	130	*/
c8d86be3 GKH	131	qc_included = ((WLAN_FC_GET_TYPE(fc) == IEEE80211_FTYPE_DATA) &&
	132	(WLAN_FC_GET_STYPE(fc) & 0x80));
	133	aad_len = 22;
	134	if (a4_included)
	135	aad_len += 6;
	136	if (qc_included) {
	137	pos = (u8 *) &hdr->addr4;
	138	if (a4_included)
	139	pos += 6;
	140	qc = *pos & 0x0f;
	141	aad_len += 2;
	142	}
	143	/* CCM Initial Block:
	144	* Flag (Include authentication header, M=3 (8-octet MIC),
	145	* L=1 (2-octet Dlen))
	146	* Nonce: 0x00 \| A2 \| PN
	147	* Dlen */
	148	b0[0] = 0x59;
	149	b0[1] = qc;
	150	memcpy(b0 + 2, hdr->addr2, ETH_ALEN);
	151	memcpy(b0 + 8, pn, CCMP_PN_LEN);
	152	b0[14] = (dlen >> 8) & 0xff;
	153	b0[15] = dlen & 0xff;
	154
	155	/* AAD:
	156	* FC with bits 4..6 and 11..13 masked to zero; 14 is always one
	157	* A1 \| A2 \| A3
	158	* SC with bits 4..15 (seq#) masked to zero
	159	* A4 (if present)
	160	* QC (if present)
	161	*/
	162	pos = (u8 *) hdr;
	163	aad[0] = 0; /* aad_len >> 8 */
	164	aad[1] = aad_len & 0xff;
	165	aad[2] = pos[0] & 0x8f;
	166	aad[3] = pos[1] & 0xc7;
	167	memcpy(aad + 4, hdr->addr1, 3 * ETH_ALEN);
	168	pos = (u8 *) &hdr->seq_ctl;
	169	aad[22] = pos[0] & 0x0f;
	170	aad[23] = 0; /* all bits masked */
	171	memset(aad + 24, 0, 8);
	172	if (a4_included)
	173	memcpy(aad + 24, hdr->addr4, ETH_ALEN);
	174	if (qc_included) {
	175	aad[a4_included ? 30 : 24] = qc;
	176	/* rest of QC masked */
	177	}
	178
	179	/* Start with the first block and AAD */
	180	ieee80211_ccmp_aes_encrypt(tfm, b0, auth);
	181	xor_block(auth, aad, AES_BLOCK_LEN);
	182	ieee80211_ccmp_aes_encrypt(tfm, auth, auth);
	183	xor_block(auth, &aad[AES_BLOCK_LEN], AES_BLOCK_LEN);
	184	ieee80211_ccmp_aes_encrypt(tfm, auth, auth);
	185	b0[0] &= 0x07;
	186	b0[14] = b0[15] = 0;
	187	ieee80211_ccmp_aes_encrypt(tfm, b0, s0);
	188	}
c8d86be3 GKH	189
	190	static int ieee80211_ccmp_encrypt(struct sk_buff skb, int hdr_len, void priv)
	191	{
	192	struct ieee80211_ccmp_data *key = priv;
	193	int data_len, i;
	194	u8 *pos;
0604384d	195	struct ieee80211_hdr_4addr *hdr;
c8d86be3 GKH	196	int blocks, last, len;
	197	u8 *mic;
	198	u8 *b0 = key->tx_b0;
	199	u8 *b = key->tx_b;
	200	u8 *e = key->tx_e;
	201	u8 *s0 = key->tx_s0;
7fdb78d0	202
c8d86be3 GKH	203	if (skb_headroom(skb) < CCMP_HDR_LEN \|\|
	204	skb_tailroom(skb) < CCMP_MIC_LEN \|\|
	205	skb->len < hdr_len)
	206	return -1;
	207
	208	data_len = skb->len - hdr_len;
	209	pos = skb_push(skb, CCMP_HDR_LEN);
	210	memmove(pos, pos + CCMP_HDR_LEN, hdr_len);
	211	pos += hdr_len;
c8d86be3 GKH	212
	213	i = CCMP_PN_LEN - 1;
	214	while (i >= 0) {
	215	key->tx_pn[i]++;
	216	if (key->tx_pn[i] != 0)
	217	break;
	218	i--;
	219	}
	220
	221	*pos++ = key->tx_pn[5];
	222	*pos++ = key->tx_pn[4];
	223	*pos++ = 0;
	224	pos++ = (key->key_idx << 6) \| (1 << 5) / Ext IV included */;
	225	*pos++ = key->tx_pn[3];
	226	*pos++ = key->tx_pn[2];
	227	*pos++ = key->tx_pn[1];
	228	*pos++ = key->tx_pn[0];
	229
0604384d	230	hdr = (struct ieee80211_hdr_4addr *)skb->data;
c8d86be3 GKH	231	mic = skb_put(skb, CCMP_MIC_LEN);
	232
	233	ccmp_init_blocks(key->tfm, hdr, key->tx_pn, data_len, b0, b, s0);
	234
	235	blocks = (data_len + AES_BLOCK_LEN - 1) / AES_BLOCK_LEN;
	236	last = data_len % AES_BLOCK_LEN;
	237
	238	for (i = 1; i <= blocks; i++) {
	239	len = (i == blocks && last) ? last : AES_BLOCK_LEN;
	240	/* Authentication */
	241	xor_block(b, pos, len);
	242	ieee80211_ccmp_aes_encrypt(key->tfm, b, b);
	243	/* Encryption, with counter */
	244	b0[14] = (i >> 8) & 0xff;
	245	b0[15] = i & 0xff;
	246	ieee80211_ccmp_aes_encrypt(key->tfm, b0, e);
	247	xor_block(pos, e, len);
	248	pos += len;
	249	}
	250
	251	for (i = 0; i < CCMP_MIC_LEN; i++)
	252	mic[i] = b[i] ^ s0[i];
7fdb78d0	253
c8d86be3 GKH	254	return 0;
	255	}
	256
	257
	258	static int ieee80211_ccmp_decrypt(struct sk_buff skb, int hdr_len, void priv)
	259	{
	260	struct ieee80211_ccmp_data *key = priv;
	261	u8 keyidx, *pos;
0604384d	262	struct ieee80211_hdr_4addr *hdr;
c8d86be3	263	u8 pn[6];
c8d86be3 GKH	264	size_t data_len = skb->len - hdr_len - CCMP_HDR_LEN - CCMP_MIC_LEN;
	265	u8 *mic = skb->data + skb->len - CCMP_MIC_LEN;
	266	u8 *b0 = key->rx_b0;
	267	u8 *b = key->rx_b;
	268	u8 *a = key->rx_a;
	269	int i, blocks, last, len;
7fdb78d0	270
c8d86be3 GKH	271	if (skb->len < hdr_len + CCMP_HDR_LEN + CCMP_MIC_LEN) {
	272	key->dot11RSNAStatsCCMPFormatErrors++;
	273	return -1;
	274	}
	275
0604384d	276	hdr = (struct ieee80211_hdr_4addr *)skb->data;
c8d86be3 GKH	277	pos = skb->data + hdr_len;
	278	keyidx = pos[3];
	279	if (!(keyidx & (1 << 5))) {
	280	if (net_ratelimit()) {
d6f272c2 YT	281	pr_debug("received packet without ExtIV flag from %pM\n",
d6f272c2 YT	282	hdr->addr2);
c8d86be3 GKH	283	}
	284	key->dot11RSNAStatsCCMPFormatErrors++;
	285	return -2;
	286	}
	287	keyidx >>= 6;
	288	if (key->key_idx != keyidx) {
d6f272c2 YT	289	pr_debug("RX tkey->key_idx=%d frame keyidx=%d priv=%p\n",
d6f272c2 YT	290	key->key_idx, keyidx, priv);
c8d86be3 GKH	291	return -6;
	292	}
	293	if (!key->key_set) {
	294	if (net_ratelimit()) {
d6f272c2 YT	295	pr_debug("received packet from %pM with keyid=%d that does not have a configured key\n",
d6f272c2 YT	296	hdr->addr2, keyidx);
c8d86be3 GKH	297	}
	298	return -3;
	299	}
	300
	301	pn[0] = pos[7];
	302	pn[1] = pos[6];
	303	pn[2] = pos[5];
	304	pn[3] = pos[4];
	305	pn[4] = pos[1];
	306	pn[5] = pos[0];
	307	pos += 8;
	308
	309	if (memcmp(pn, key->rx_pn, CCMP_PN_LEN) <= 0) {
	310	if (net_ratelimit()) {
d6f272c2 YT	311	pr_debug("replay detected: STA=%pM previous PN %pm received PN %pm\n",
d6f272c2 YT	312	hdr->addr2, key->rx_pn, pn);
c8d86be3 GKH	313	}
	314	key->dot11RSNAStatsCCMPReplays++;
	315	return -4;
	316	}
	317
c8d86be3 GKH	318	ccmp_init_blocks(key->tfm, hdr, pn, data_len, b0, a, b);
	319	xor_block(mic, b, CCMP_MIC_LEN);
	320
	321	blocks = (data_len + AES_BLOCK_LEN - 1) / AES_BLOCK_LEN;
	322	last = data_len % AES_BLOCK_LEN;
	323
	324	for (i = 1; i <= blocks; i++) {
	325	len = (i == blocks && last) ? last : AES_BLOCK_LEN;
	326	/* Decrypt, with counter */
	327	b0[14] = (i >> 8) & 0xff;
	328	b0[15] = i & 0xff;
	329	ieee80211_ccmp_aes_encrypt(key->tfm, b0, b);
	330	xor_block(pos, b, len);
	331	/* Authentication */
	332	xor_block(a, pos, len);
	333	ieee80211_ccmp_aes_encrypt(key->tfm, a, a);
	334	pos += len;
	335	}
	336
	337	if (memcmp(mic, a, CCMP_MIC_LEN) != 0) {
937afb70	338	if (net_ratelimit())
d6f272c2	339	pr_debug("decrypt failed: STA=%pM\n", hdr->addr2);
937afb70	340
c8d86be3 GKH	341	key->dot11RSNAStatsCCMPDecryptErrors++;
	342	return -5;
	343	}
	344
	345	memcpy(key->rx_pn, pn, CCMP_PN_LEN);
	346
c8d86be3 GKH	347	/* Remove hdr and MIC */
	348	memmove(skb->data + CCMP_HDR_LEN, skb->data, hdr_len);
	349	skb_pull(skb, CCMP_HDR_LEN);
	350	skb_trim(skb, skb->len - CCMP_MIC_LEN);
	351
	352	return keyidx;
	353	}
	354
	355
	356	static int ieee80211_ccmp_set_key(void key, int len, u8 seq, void *priv)
	357	{
	358	struct ieee80211_ccmp_data *data = priv;
	359	int keyidx;
	360	struct crypto_tfm *tfm = data->tfm;
	361
	362	keyidx = data->key_idx;
	363	memset(data, 0, sizeof(*data));
	364	data->key_idx = keyidx;
	365	data->tfm = tfm;
	366	if (len == CCMP_TK_LEN) {
	367	memcpy(data->key, key, CCMP_TK_LEN);
	368	data->key_set = 1;
	369	if (seq) {
	370	data->rx_pn[0] = seq[5];
	371	data->rx_pn[1] = seq[4];
	372	data->rx_pn[2] = seq[3];
	373	data->rx_pn[3] = seq[2];
	374	data->rx_pn[4] = seq[1];
	375	data->rx_pn[5] = seq[0];
	376	}
	377	crypto_cipher_setkey((void *)data->tfm, data->key, CCMP_TK_LEN);
	378	} else if (len == 0)
	379	data->key_set = 0;
	380	else
	381	return -1;
	382
	383	return 0;
	384	}
	385
	386
	387	static int ieee80211_ccmp_get_key(void key, int len, u8 seq, void *priv)
	388	{
	389	struct ieee80211_ccmp_data *data = priv;
	390
	391	if (len < CCMP_TK_LEN)
	392	return -1;
	393
	394	if (!data->key_set)
	395	return 0;
	396	memcpy(key, data->key, CCMP_TK_LEN);
	397
	398	if (seq) {
	399	seq[0] = data->tx_pn[5];
	400	seq[1] = data->tx_pn[4];
	401	seq[2] = data->tx_pn[3];
	402	seq[3] = data->tx_pn[2];
	403	seq[4] = data->tx_pn[1];
	404	seq[5] = data->tx_pn[0];
	405	}
	406
	407	return CCMP_TK_LEN;
	408	}
	409
	410
5bd6e9e0	411	static char ieee80211_ccmp_print_stats(char p, void *priv)
c8d86be3 GKH	412	{
c8d86be3 GKH	413	struct ieee80211_ccmp_data *ccmp = priv;
c6a2c52f RK	414	p += sprintf(p,
c6a2c52f RK	415	"key[%d] alg=CCMP key_set=%d tx_pn=%pm rx_pn=%pm format_errors=%d replays=%d decrypt_errors=%d\n",
c8d86be3	416	ccmp->key_idx, ccmp->key_set,
0ee9f67c	417	ccmp->tx_pn, ccmp->rx_pn,
c8d86be3 GKH	418	ccmp->dot11RSNAStatsCCMPFormatErrors,
	419	ccmp->dot11RSNAStatsCCMPReplays,
	420	ccmp->dot11RSNAStatsCCMPDecryptErrors);
	421
	422	return p;
	423	}
	424
	425	void ieee80211_ccmp_null(void)
	426	{
c8d86be3 GKH	427	return;
	428	}
	429	static struct ieee80211_crypto_ops ieee80211_crypt_ccmp = {
	430	.name = "CCMP",
	431	.init = ieee80211_ccmp_init,
	432	.deinit = ieee80211_ccmp_deinit,
	433	.encrypt_mpdu = ieee80211_ccmp_encrypt,
	434	.decrypt_mpdu = ieee80211_ccmp_decrypt,
	435	.encrypt_msdu = NULL,
	436	.decrypt_msdu = NULL,
	437	.set_key = ieee80211_ccmp_set_key,
	438	.get_key = ieee80211_ccmp_get_key,
	439	.print_stats = ieee80211_ccmp_print_stats,
	440	.extra_prefix_len = CCMP_HDR_LEN,
	441	.extra_postfix_len = CCMP_MIC_LEN,
	442	.owner = THIS_MODULE,
	443	};
	444
	445
	446	int ieee80211_crypto_ccmp_init(void)
	447	{
	448	return ieee80211_register_crypto_ops(&ieee80211_crypt_ccmp);
	449	}
	450
	451
	452	void ieee80211_crypto_ccmp_exit(void)
	453	{
	454	ieee80211_unregister_crypto_ops(&ieee80211_crypt_ccmp);
	455	}