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v4.10.11
 
   1/*
   2 * Copyright 2002-2004, Instant802 Networks, Inc.
   3 * Copyright 2008, Jouni Malinen <j@w1.fi>
   4 * Copyright (C) 2016 Intel Deutschland GmbH
   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.
   9 */
  10
  11#include <linux/netdevice.h>
  12#include <linux/types.h>
  13#include <linux/skbuff.h>
  14#include <linux/compiler.h>
  15#include <linux/ieee80211.h>
  16#include <linux/gfp.h>
  17#include <asm/unaligned.h>
  18#include <net/mac80211.h>
  19#include <crypto/aes.h>
 
  20
  21#include "ieee80211_i.h"
  22#include "michael.h"
  23#include "tkip.h"
  24#include "aes_ccm.h"
  25#include "aes_cmac.h"
  26#include "aes_gmac.h"
  27#include "aes_gcm.h"
  28#include "wpa.h"
  29
  30ieee80211_tx_result
  31ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
  32{
  33	u8 *data, *key, *mic;
  34	size_t data_len;
  35	unsigned int hdrlen;
  36	struct ieee80211_hdr *hdr;
  37	struct sk_buff *skb = tx->skb;
  38	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  39	int tail;
  40
  41	hdr = (struct ieee80211_hdr *)skb->data;
  42	if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
  43	    skb->len < 24 || !ieee80211_is_data_present(hdr->frame_control))
  44		return TX_CONTINUE;
  45
  46	hdrlen = ieee80211_hdrlen(hdr->frame_control);
  47	if (skb->len < hdrlen)
  48		return TX_DROP;
  49
  50	data = skb->data + hdrlen;
  51	data_len = skb->len - hdrlen;
  52
  53	if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) {
  54		/* Need to use software crypto for the test */
  55		info->control.hw_key = NULL;
  56	}
  57
  58	if (info->control.hw_key &&
  59	    (info->flags & IEEE80211_TX_CTL_DONTFRAG ||
  60	     ieee80211_hw_check(&tx->local->hw, SUPPORTS_TX_FRAG)) &&
  61	    !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) {
  62		/* hwaccel - with no need for SW-generated MMIC */
 
  63		return TX_CONTINUE;
  64	}
  65
  66	tail = MICHAEL_MIC_LEN;
  67	if (!info->control.hw_key)
  68		tail += IEEE80211_TKIP_ICV_LEN;
  69
  70	if (WARN(skb_tailroom(skb) < tail ||
  71		 skb_headroom(skb) < IEEE80211_TKIP_IV_LEN,
  72		 "mmic: not enough head/tail (%d/%d,%d/%d)\n",
  73		 skb_headroom(skb), IEEE80211_TKIP_IV_LEN,
  74		 skb_tailroom(skb), tail))
  75		return TX_DROP;
  76
  77	key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY];
  78	mic = skb_put(skb, MICHAEL_MIC_LEN);
 
 
 
 
 
 
 
 
  79	michael_mic(key, hdr, data, data_len, mic);
  80	if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE))
  81		mic[0]++;
  82
  83	return TX_CONTINUE;
  84}
  85
  86
  87ieee80211_rx_result
  88ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
  89{
  90	u8 *data, *key = NULL;
  91	size_t data_len;
  92	unsigned int hdrlen;
  93	u8 mic[MICHAEL_MIC_LEN];
  94	struct sk_buff *skb = rx->skb;
  95	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
  96	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
  97
  98	/*
  99	 * it makes no sense to check for MIC errors on anything other
 100	 * than data frames.
 101	 */
 102	if (!ieee80211_is_data_present(hdr->frame_control))
 103		return RX_CONTINUE;
 104
 105	/*
 106	 * No way to verify the MIC if the hardware stripped it or
 107	 * the IV with the key index. In this case we have solely rely
 108	 * on the driver to set RX_FLAG_MMIC_ERROR in the event of a
 109	 * MIC failure report.
 110	 */
 111	if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) {
 112		if (status->flag & RX_FLAG_MMIC_ERROR)
 113			goto mic_fail_no_key;
 114
 115		if (!(status->flag & RX_FLAG_IV_STRIPPED) && rx->key &&
 116		    rx->key->conf.cipher == WLAN_CIPHER_SUITE_TKIP)
 117			goto update_iv;
 118
 119		return RX_CONTINUE;
 120	}
 121
 122	/*
 123	 * Some hardware seems to generate Michael MIC failure reports; even
 124	 * though, the frame was not encrypted with TKIP and therefore has no
 125	 * MIC. Ignore the flag them to avoid triggering countermeasures.
 126	 */
 127	if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
 128	    !(status->flag & RX_FLAG_DECRYPTED))
 129		return RX_CONTINUE;
 130
 131	if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) {
 132		/*
 133		 * APs with pairwise keys should never receive Michael MIC
 134		 * errors for non-zero keyidx because these are reserved for
 135		 * group keys and only the AP is sending real multicast
 136		 * frames in the BSS.
 137		 */
 138		return RX_DROP_UNUSABLE;
 139	}
 140
 141	if (status->flag & RX_FLAG_MMIC_ERROR)
 142		goto mic_fail;
 143
 144	hdrlen = ieee80211_hdrlen(hdr->frame_control);
 145	if (skb->len < hdrlen + MICHAEL_MIC_LEN)
 146		return RX_DROP_UNUSABLE;
 147
 148	if (skb_linearize(rx->skb))
 149		return RX_DROP_UNUSABLE;
 150	hdr = (void *)skb->data;
 151
 152	data = skb->data + hdrlen;
 153	data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
 154	key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY];
 155	michael_mic(key, hdr, data, data_len, mic);
 156	if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0)
 157		goto mic_fail;
 158
 159	/* remove Michael MIC from payload */
 160	skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
 161
 162update_iv:
 163	/* update IV in key information to be able to detect replays */
 164	rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip_iv32;
 165	rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip_iv16;
 166
 167	return RX_CONTINUE;
 168
 169mic_fail:
 170	rx->key->u.tkip.mic_failures++;
 171
 172mic_fail_no_key:
 173	/*
 174	 * In some cases the key can be unset - e.g. a multicast packet, in
 175	 * a driver that supports HW encryption. Send up the key idx only if
 176	 * the key is set.
 177	 */
 178	cfg80211_michael_mic_failure(rx->sdata->dev, hdr->addr2,
 179				     is_multicast_ether_addr(hdr->addr1) ?
 180				     NL80211_KEYTYPE_GROUP :
 181				     NL80211_KEYTYPE_PAIRWISE,
 182				     rx->key ? rx->key->conf.keyidx : -1,
 183				     NULL, GFP_ATOMIC);
 184	return RX_DROP_UNUSABLE;
 185}
 186
 187static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
 188{
 189	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 190	struct ieee80211_key *key = tx->key;
 191	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 192	unsigned int hdrlen;
 193	int len, tail;
 194	u64 pn;
 195	u8 *pos;
 196
 197	if (info->control.hw_key &&
 198	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 199	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
 200		/* hwaccel - with no need for software-generated IV */
 201		return 0;
 202	}
 203
 204	hdrlen = ieee80211_hdrlen(hdr->frame_control);
 205	len = skb->len - hdrlen;
 206
 207	if (info->control.hw_key)
 208		tail = 0;
 209	else
 210		tail = IEEE80211_TKIP_ICV_LEN;
 211
 212	if (WARN_ON(skb_tailroom(skb) < tail ||
 213		    skb_headroom(skb) < IEEE80211_TKIP_IV_LEN))
 214		return -1;
 215
 216	pos = skb_push(skb, IEEE80211_TKIP_IV_LEN);
 217	memmove(pos, pos + IEEE80211_TKIP_IV_LEN, hdrlen);
 218	pos += hdrlen;
 219
 220	/* the HW only needs room for the IV, but not the actual IV */
 221	if (info->control.hw_key &&
 222	    (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 223		return 0;
 224
 225	/* Increase IV for the frame */
 226	pn = atomic64_inc_return(&key->conf.tx_pn);
 227	pos = ieee80211_tkip_add_iv(pos, &key->conf, pn);
 228
 229	/* hwaccel - with software IV */
 230	if (info->control.hw_key)
 231		return 0;
 232
 233	/* Add room for ICV */
 234	skb_put(skb, IEEE80211_TKIP_ICV_LEN);
 235
 236	return ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
 237					   key, skb, pos, len);
 238}
 239
 240
 241ieee80211_tx_result
 242ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
 243{
 244	struct sk_buff *skb;
 245
 246	ieee80211_tx_set_protected(tx);
 247
 248	skb_queue_walk(&tx->skbs, skb) {
 249		if (tkip_encrypt_skb(tx, skb) < 0)
 250			return TX_DROP;
 251	}
 252
 253	return TX_CONTINUE;
 254}
 255
 256
 257ieee80211_rx_result
 258ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
 259{
 260	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 261	int hdrlen, res, hwaccel = 0;
 262	struct ieee80211_key *key = rx->key;
 263	struct sk_buff *skb = rx->skb;
 264	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 265
 266	hdrlen = ieee80211_hdrlen(hdr->frame_control);
 267
 268	if (!ieee80211_is_data(hdr->frame_control))
 269		return RX_CONTINUE;
 270
 271	if (!rx->sta || skb->len - hdrlen < 12)
 272		return RX_DROP_UNUSABLE;
 273
 274	/* it may be possible to optimize this a bit more */
 275	if (skb_linearize(rx->skb))
 276		return RX_DROP_UNUSABLE;
 277	hdr = (void *)skb->data;
 278
 279	/*
 280	 * Let TKIP code verify IV, but skip decryption.
 281	 * In the case where hardware checks the IV as well,
 282	 * we don't even get here, see ieee80211_rx_h_decrypt()
 283	 */
 284	if (status->flag & RX_FLAG_DECRYPTED)
 285		hwaccel = 1;
 286
 287	res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,
 288					  key, skb->data + hdrlen,
 289					  skb->len - hdrlen, rx->sta->sta.addr,
 290					  hdr->addr1, hwaccel, rx->security_idx,
 291					  &rx->tkip_iv32,
 292					  &rx->tkip_iv16);
 293	if (res != TKIP_DECRYPT_OK)
 294		return RX_DROP_UNUSABLE;
 295
 296	/* Trim ICV */
 297	skb_trim(skb, skb->len - IEEE80211_TKIP_ICV_LEN);
 
 298
 299	/* Remove IV */
 300	memmove(skb->data + IEEE80211_TKIP_IV_LEN, skb->data, hdrlen);
 301	skb_pull(skb, IEEE80211_TKIP_IV_LEN);
 302
 303	return RX_CONTINUE;
 304}
 305
 306
 307static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad)
 
 
 
 308{
 
 309	__le16 mask_fc;
 310	int a4_included, mgmt;
 311	u8 qos_tid;
 312	u16 len_a;
 313	unsigned int hdrlen;
 314	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 315
 316	/*
 317	 * Mask FC: zero subtype b4 b5 b6 (if not mgmt)
 318	 * Retry, PwrMgt, MoreData; set Protected
 319	 */
 320	mgmt = ieee80211_is_mgmt(hdr->frame_control);
 321	mask_fc = hdr->frame_control;
 322	mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
 323				IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
 324	if (!mgmt)
 325		mask_fc &= ~cpu_to_le16(0x0070);
 326	mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
 327
 328	hdrlen = ieee80211_hdrlen(hdr->frame_control);
 329	len_a = hdrlen - 2;
 330	a4_included = ieee80211_has_a4(hdr->frame_control);
 
 
 331
 332	if (ieee80211_is_data_qos(hdr->frame_control))
 333		qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
 334	else
 
 
 335		qos_tid = 0;
 336
 337	/* In CCM, the initial vectors (IV) used for CTR mode encryption and CBC
 338	 * mode authentication are not allowed to collide, yet both are derived
 339	 * from this vector b_0. We only set L := 1 here to indicate that the
 340	 * data size can be represented in (L+1) bytes. The CCM layer will take
 341	 * care of storing the data length in the top (L+1) bytes and setting
 342	 * and clearing the other bits as is required to derive the two IVs.
 343	 */
 344	b_0[0] = 0x1;
 345
 346	/* Nonce: Nonce Flags | A2 | PN
 347	 * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7)
 348	 */
 349	b_0[1] = qos_tid | (mgmt << 4);
 350	memcpy(&b_0[2], hdr->addr2, ETH_ALEN);
 351	memcpy(&b_0[8], pn, IEEE80211_CCMP_PN_LEN);
 352
 353	/* AAD (extra authenticate-only data) / masked 802.11 header
 354	 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */
 355	put_unaligned_be16(len_a, &aad[0]);
 356	put_unaligned(mask_fc, (__le16 *)&aad[2]);
 357	memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
 358
 359	/* Mask Seq#, leave Frag# */
 360	aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
 361	aad[23] = 0;
 362
 363	if (a4_included) {
 364		memcpy(&aad[24], hdr->addr4, ETH_ALEN);
 365		aad[30] = qos_tid;
 366		aad[31] = 0;
 367	} else {
 368		memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
 369		aad[24] = qos_tid;
 370	}
 
 
 371}
 372
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 373
 374static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
 375{
 376	hdr[0] = pn[5];
 377	hdr[1] = pn[4];
 378	hdr[2] = 0;
 379	hdr[3] = 0x20 | (key_id << 6);
 380	hdr[4] = pn[3];
 381	hdr[5] = pn[2];
 382	hdr[6] = pn[1];
 383	hdr[7] = pn[0];
 384}
 385
 386
 387static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr)
 388{
 389	pn[0] = hdr[7];
 390	pn[1] = hdr[6];
 391	pn[2] = hdr[5];
 392	pn[3] = hdr[4];
 393	pn[4] = hdr[1];
 394	pn[5] = hdr[0];
 395}
 396
 397
 398static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb,
 399			    unsigned int mic_len)
 400{
 401	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 402	struct ieee80211_key *key = tx->key;
 403	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 404	int hdrlen, len, tail;
 405	u8 *pos;
 406	u8 pn[6];
 407	u64 pn64;
 408	u8 aad[CCM_AAD_LEN];
 409	u8 b_0[AES_BLOCK_SIZE];
 410
 411	if (info->control.hw_key &&
 412	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 413	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 414	    !((info->control.hw_key->flags &
 415	       IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
 416	      ieee80211_is_mgmt(hdr->frame_control))) {
 417		/*
 418		 * hwaccel has no need for preallocated room for CCMP
 419		 * header or MIC fields
 420		 */
 421		return 0;
 422	}
 423
 424	hdrlen = ieee80211_hdrlen(hdr->frame_control);
 425	len = skb->len - hdrlen;
 426
 427	if (info->control.hw_key)
 428		tail = 0;
 429	else
 430		tail = mic_len;
 431
 432	if (WARN_ON(skb_tailroom(skb) < tail ||
 433		    skb_headroom(skb) < IEEE80211_CCMP_HDR_LEN))
 434		return -1;
 435
 436	pos = skb_push(skb, IEEE80211_CCMP_HDR_LEN);
 437	memmove(pos, pos + IEEE80211_CCMP_HDR_LEN, hdrlen);
 438
 439	/* the HW only needs room for the IV, but not the actual IV */
 440	if (info->control.hw_key &&
 441	    (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 442		return 0;
 443
 444	hdr = (struct ieee80211_hdr *) pos;
 445	pos += hdrlen;
 446
 447	pn64 = atomic64_inc_return(&key->conf.tx_pn);
 448
 449	pn[5] = pn64;
 450	pn[4] = pn64 >> 8;
 451	pn[3] = pn64 >> 16;
 452	pn[2] = pn64 >> 24;
 453	pn[1] = pn64 >> 32;
 454	pn[0] = pn64 >> 40;
 455
 456	ccmp_pn2hdr(pos, pn, key->conf.keyidx);
 457
 458	/* hwaccel - with software CCMP header */
 459	if (info->control.hw_key)
 460		return 0;
 461
 462	pos += IEEE80211_CCMP_HDR_LEN;
 463	ccmp_special_blocks(skb, pn, b_0, aad);
 464	return ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, b_0, aad, pos, len,
 465					 skb_put(skb, mic_len), mic_len);
 466}
 467
 468
 469ieee80211_tx_result
 470ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx,
 471			      unsigned int mic_len)
 472{
 473	struct sk_buff *skb;
 474
 475	ieee80211_tx_set_protected(tx);
 476
 477	skb_queue_walk(&tx->skbs, skb) {
 478		if (ccmp_encrypt_skb(tx, skb, mic_len) < 0)
 479			return TX_DROP;
 480	}
 481
 482	return TX_CONTINUE;
 483}
 484
 485
 486ieee80211_rx_result
 487ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx,
 488			      unsigned int mic_len)
 489{
 490	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 491	int hdrlen;
 492	struct ieee80211_key *key = rx->key;
 493	struct sk_buff *skb = rx->skb;
 494	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 495	u8 pn[IEEE80211_CCMP_PN_LEN];
 496	int data_len;
 497	int queue;
 498
 499	hdrlen = ieee80211_hdrlen(hdr->frame_control);
 500
 501	if (!ieee80211_is_data(hdr->frame_control) &&
 502	    !ieee80211_is_robust_mgmt_frame(skb))
 503		return RX_CONTINUE;
 504
 505	if (status->flag & RX_FLAG_DECRYPTED) {
 506		if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_CCMP_HDR_LEN))
 507			return RX_DROP_UNUSABLE;
 508		if (status->flag & RX_FLAG_MIC_STRIPPED)
 509			mic_len = 0;
 510	} else {
 511		if (skb_linearize(rx->skb))
 512			return RX_DROP_UNUSABLE;
 513	}
 514
 
 
 
 515	data_len = skb->len - hdrlen - IEEE80211_CCMP_HDR_LEN - mic_len;
 516	if (!rx->sta || data_len < 0)
 517		return RX_DROP_UNUSABLE;
 518
 519	if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
 520		int res;
 521
 522		ccmp_hdr2pn(pn, skb->data + hdrlen);
 523
 524		queue = rx->security_idx;
 525
 526		res = memcmp(pn, key->u.ccmp.rx_pn[queue],
 527			     IEEE80211_CCMP_PN_LEN);
 528		if (res < 0 ||
 529		    (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
 530			key->u.ccmp.replays++;
 531			return RX_DROP_UNUSABLE;
 532		}
 533
 534		if (!(status->flag & RX_FLAG_DECRYPTED)) {
 535			u8 aad[2 * AES_BLOCK_SIZE];
 536			u8 b_0[AES_BLOCK_SIZE];
 537			/* hardware didn't decrypt/verify MIC */
 538			ccmp_special_blocks(skb, pn, b_0, aad);
 539
 540			if (ieee80211_aes_ccm_decrypt(
 541				    key->u.ccmp.tfm, b_0, aad,
 542				    skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN,
 543				    data_len,
 544				    skb->data + skb->len - mic_len, mic_len))
 545				return RX_DROP_UNUSABLE;
 546		}
 547
 548		memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN);
 
 
 549	}
 550
 551	/* Remove CCMP header and MIC */
 552	if (pskb_trim(skb, skb->len - mic_len))
 553		return RX_DROP_UNUSABLE;
 554	memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen);
 555	skb_pull(skb, IEEE80211_CCMP_HDR_LEN);
 556
 557	return RX_CONTINUE;
 558}
 559
 560static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad)
 561{
 562	__le16 mask_fc;
 563	u8 qos_tid;
 564	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 565
 566	memcpy(j_0, hdr->addr2, ETH_ALEN);
 567	memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN);
 568	j_0[13] = 0;
 569	j_0[14] = 0;
 570	j_0[AES_BLOCK_SIZE - 1] = 0x01;
 571
 572	/* AAD (extra authenticate-only data) / masked 802.11 header
 573	 * FC | A1 | A2 | A3 | SC | [A4] | [QC]
 574	 */
 575	put_unaligned_be16(ieee80211_hdrlen(hdr->frame_control) - 2, &aad[0]);
 576	/* Mask FC: zero subtype b4 b5 b6 (if not mgmt)
 577	 * Retry, PwrMgt, MoreData; set Protected
 578	 */
 579	mask_fc = hdr->frame_control;
 580	mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
 581				IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
 582	if (!ieee80211_is_mgmt(hdr->frame_control))
 583		mask_fc &= ~cpu_to_le16(0x0070);
 584	mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
 585
 586	put_unaligned(mask_fc, (__le16 *)&aad[2]);
 587	memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
 588
 589	/* Mask Seq#, leave Frag# */
 590	aad[22] = *((u8 *)&hdr->seq_ctrl) & 0x0f;
 591	aad[23] = 0;
 592
 593	if (ieee80211_is_data_qos(hdr->frame_control))
 594		qos_tid = *ieee80211_get_qos_ctl(hdr) &
 595			IEEE80211_QOS_CTL_TID_MASK;
 596	else
 597		qos_tid = 0;
 598
 599	if (ieee80211_has_a4(hdr->frame_control)) {
 600		memcpy(&aad[24], hdr->addr4, ETH_ALEN);
 601		aad[30] = qos_tid;
 602		aad[31] = 0;
 603	} else {
 604		memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
 605		aad[24] = qos_tid;
 606	}
 607}
 608
 609static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id)
 610{
 611	hdr[0] = pn[5];
 612	hdr[1] = pn[4];
 613	hdr[2] = 0;
 614	hdr[3] = 0x20 | (key_id << 6);
 615	hdr[4] = pn[3];
 616	hdr[5] = pn[2];
 617	hdr[6] = pn[1];
 618	hdr[7] = pn[0];
 619}
 620
 621static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr)
 622{
 623	pn[0] = hdr[7];
 624	pn[1] = hdr[6];
 625	pn[2] = hdr[5];
 626	pn[3] = hdr[4];
 627	pn[4] = hdr[1];
 628	pn[5] = hdr[0];
 629}
 630
 631static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
 632{
 633	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 634	struct ieee80211_key *key = tx->key;
 635	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 636	int hdrlen, len, tail;
 637	u8 *pos;
 638	u8 pn[6];
 639	u64 pn64;
 640	u8 aad[GCM_AAD_LEN];
 641	u8 j_0[AES_BLOCK_SIZE];
 642
 643	if (info->control.hw_key &&
 644	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 645	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 646	    !((info->control.hw_key->flags &
 647	       IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
 648	      ieee80211_is_mgmt(hdr->frame_control))) {
 649		/* hwaccel has no need for preallocated room for GCMP
 650		 * header or MIC fields
 651		 */
 652		return 0;
 653	}
 654
 655	hdrlen = ieee80211_hdrlen(hdr->frame_control);
 656	len = skb->len - hdrlen;
 657
 658	if (info->control.hw_key)
 659		tail = 0;
 660	else
 661		tail = IEEE80211_GCMP_MIC_LEN;
 662
 663	if (WARN_ON(skb_tailroom(skb) < tail ||
 664		    skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN))
 665		return -1;
 666
 667	pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN);
 668	memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen);
 669	skb_set_network_header(skb, skb_network_offset(skb) +
 670				    IEEE80211_GCMP_HDR_LEN);
 671
 672	/* the HW only needs room for the IV, but not the actual IV */
 673	if (info->control.hw_key &&
 674	    (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 675		return 0;
 676
 677	hdr = (struct ieee80211_hdr *)pos;
 678	pos += hdrlen;
 679
 680	pn64 = atomic64_inc_return(&key->conf.tx_pn);
 681
 682	pn[5] = pn64;
 683	pn[4] = pn64 >> 8;
 684	pn[3] = pn64 >> 16;
 685	pn[2] = pn64 >> 24;
 686	pn[1] = pn64 >> 32;
 687	pn[0] = pn64 >> 40;
 688
 689	gcmp_pn2hdr(pos, pn, key->conf.keyidx);
 690
 691	/* hwaccel - with software GCMP header */
 692	if (info->control.hw_key)
 693		return 0;
 694
 695	pos += IEEE80211_GCMP_HDR_LEN;
 696	gcmp_special_blocks(skb, pn, j_0, aad);
 697	return ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len,
 698					 skb_put(skb, IEEE80211_GCMP_MIC_LEN));
 699}
 700
 701ieee80211_tx_result
 702ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx)
 703{
 704	struct sk_buff *skb;
 705
 706	ieee80211_tx_set_protected(tx);
 707
 708	skb_queue_walk(&tx->skbs, skb) {
 709		if (gcmp_encrypt_skb(tx, skb) < 0)
 710			return TX_DROP;
 711	}
 712
 713	return TX_CONTINUE;
 714}
 715
 716ieee80211_rx_result
 717ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
 718{
 719	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 720	int hdrlen;
 721	struct ieee80211_key *key = rx->key;
 722	struct sk_buff *skb = rx->skb;
 723	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 724	u8 pn[IEEE80211_GCMP_PN_LEN];
 725	int data_len, queue, mic_len = IEEE80211_GCMP_MIC_LEN;
 726
 727	hdrlen = ieee80211_hdrlen(hdr->frame_control);
 728
 729	if (!ieee80211_is_data(hdr->frame_control) &&
 730	    !ieee80211_is_robust_mgmt_frame(skb))
 731		return RX_CONTINUE;
 732
 733	if (status->flag & RX_FLAG_DECRYPTED) {
 734		if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN))
 735			return RX_DROP_UNUSABLE;
 736		if (status->flag & RX_FLAG_MIC_STRIPPED)
 737			mic_len = 0;
 738	} else {
 739		if (skb_linearize(rx->skb))
 740			return RX_DROP_UNUSABLE;
 741	}
 742
 
 
 
 743	data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN - mic_len;
 744	if (!rx->sta || data_len < 0)
 745		return RX_DROP_UNUSABLE;
 746
 747	if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
 748		int res;
 749
 750		gcmp_hdr2pn(pn, skb->data + hdrlen);
 751
 752		queue = rx->security_idx;
 753
 754		res = memcmp(pn, key->u.gcmp.rx_pn[queue],
 755			     IEEE80211_GCMP_PN_LEN);
 756		if (res < 0 ||
 757		    (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
 758			key->u.gcmp.replays++;
 759			return RX_DROP_UNUSABLE;
 760		}
 761
 762		if (!(status->flag & RX_FLAG_DECRYPTED)) {
 763			u8 aad[2 * AES_BLOCK_SIZE];
 764			u8 j_0[AES_BLOCK_SIZE];
 765			/* hardware didn't decrypt/verify MIC */
 766			gcmp_special_blocks(skb, pn, j_0, aad);
 767
 768			if (ieee80211_aes_gcm_decrypt(
 769				    key->u.gcmp.tfm, j_0, aad,
 770				    skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN,
 771				    data_len,
 772				    skb->data + skb->len -
 773				    IEEE80211_GCMP_MIC_LEN))
 774				return RX_DROP_UNUSABLE;
 775		}
 776
 777		memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN);
 
 
 778	}
 779
 780	/* Remove GCMP header and MIC */
 781	if (pskb_trim(skb, skb->len - mic_len))
 782		return RX_DROP_UNUSABLE;
 783	memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen);
 784	skb_pull(skb, IEEE80211_GCMP_HDR_LEN);
 785
 786	return RX_CONTINUE;
 787}
 788
 789static ieee80211_tx_result
 790ieee80211_crypto_cs_encrypt(struct ieee80211_tx_data *tx,
 791			    struct sk_buff *skb)
 792{
 793	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 794	struct ieee80211_key *key = tx->key;
 795	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 796	int hdrlen;
 797	u8 *pos, iv_len = key->conf.iv_len;
 798
 799	if (info->control.hw_key &&
 800	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
 801		/* hwaccel has no need for preallocated head room */
 802		return TX_CONTINUE;
 803	}
 804
 805	if (unlikely(skb_headroom(skb) < iv_len &&
 806		     pskb_expand_head(skb, iv_len, 0, GFP_ATOMIC)))
 807		return TX_DROP;
 808
 809	hdrlen = ieee80211_hdrlen(hdr->frame_control);
 810
 811	pos = skb_push(skb, iv_len);
 812	memmove(pos, pos + iv_len, hdrlen);
 813
 814	return TX_CONTINUE;
 815}
 816
 817static inline int ieee80211_crypto_cs_pn_compare(u8 *pn1, u8 *pn2, int len)
 818{
 819	int i;
 820
 821	/* pn is little endian */
 822	for (i = len - 1; i >= 0; i--) {
 823		if (pn1[i] < pn2[i])
 824			return -1;
 825		else if (pn1[i] > pn2[i])
 826			return 1;
 827	}
 828
 829	return 0;
 830}
 831
 832static ieee80211_rx_result
 833ieee80211_crypto_cs_decrypt(struct ieee80211_rx_data *rx)
 834{
 835	struct ieee80211_key *key = rx->key;
 836	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 837	const struct ieee80211_cipher_scheme *cs = NULL;
 838	int hdrlen = ieee80211_hdrlen(hdr->frame_control);
 839	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
 840	int data_len;
 841	u8 *rx_pn;
 842	u8 *skb_pn;
 843	u8 qos_tid;
 844
 845	if (!rx->sta || !rx->sta->cipher_scheme ||
 846	    !(status->flag & RX_FLAG_DECRYPTED))
 847		return RX_DROP_UNUSABLE;
 848
 849	if (!ieee80211_is_data(hdr->frame_control))
 850		return RX_CONTINUE;
 851
 852	cs = rx->sta->cipher_scheme;
 853
 854	data_len = rx->skb->len - hdrlen - cs->hdr_len;
 855
 856	if (data_len < 0)
 857		return RX_DROP_UNUSABLE;
 858
 859	if (ieee80211_is_data_qos(hdr->frame_control))
 860		qos_tid = *ieee80211_get_qos_ctl(hdr) &
 861				IEEE80211_QOS_CTL_TID_MASK;
 862	else
 863		qos_tid = 0;
 864
 865	if (skb_linearize(rx->skb))
 866		return RX_DROP_UNUSABLE;
 867
 868	hdr = (struct ieee80211_hdr *)rx->skb->data;
 869
 870	rx_pn = key->u.gen.rx_pn[qos_tid];
 871	skb_pn = rx->skb->data + hdrlen + cs->pn_off;
 872
 873	if (ieee80211_crypto_cs_pn_compare(skb_pn, rx_pn, cs->pn_len) <= 0)
 874		return RX_DROP_UNUSABLE;
 875
 876	memcpy(rx_pn, skb_pn, cs->pn_len);
 877
 878	/* remove security header and MIC */
 879	if (pskb_trim(rx->skb, rx->skb->len - cs->mic_len))
 880		return RX_DROP_UNUSABLE;
 881
 882	memmove(rx->skb->data + cs->hdr_len, rx->skb->data, hdrlen);
 883	skb_pull(rx->skb, cs->hdr_len);
 884
 885	return RX_CONTINUE;
 886}
 887
 888static void bip_aad(struct sk_buff *skb, u8 *aad)
 889{
 890	__le16 mask_fc;
 891	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 892
 893	/* BIP AAD: FC(masked) || A1 || A2 || A3 */
 894
 895	/* FC type/subtype */
 896	/* Mask FC Retry, PwrMgt, MoreData flags to zero */
 897	mask_fc = hdr->frame_control;
 898	mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM |
 899				IEEE80211_FCTL_MOREDATA);
 900	put_unaligned(mask_fc, (__le16 *) &aad[0]);
 901	/* A1 || A2 || A3 */
 902	memcpy(aad + 2, &hdr->addr1, 3 * ETH_ALEN);
 903}
 904
 905
 906static inline void bip_ipn_set64(u8 *d, u64 pn)
 907{
 908	*d++ = pn;
 909	*d++ = pn >> 8;
 910	*d++ = pn >> 16;
 911	*d++ = pn >> 24;
 912	*d++ = pn >> 32;
 913	*d = pn >> 40;
 914}
 915
 916static inline void bip_ipn_swap(u8 *d, const u8 *s)
 917{
 918	*d++ = s[5];
 919	*d++ = s[4];
 920	*d++ = s[3];
 921	*d++ = s[2];
 922	*d++ = s[1];
 923	*d = s[0];
 924}
 925
 926
 927ieee80211_tx_result
 928ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
 929{
 930	struct sk_buff *skb;
 931	struct ieee80211_tx_info *info;
 932	struct ieee80211_key *key = tx->key;
 933	struct ieee80211_mmie *mmie;
 934	u8 aad[20];
 935	u64 pn64;
 936
 937	if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
 938		return TX_DROP;
 939
 940	skb = skb_peek(&tx->skbs);
 941
 942	info = IEEE80211_SKB_CB(skb);
 943
 944	if (info->control.hw_key)
 
 945		return TX_CONTINUE;
 946
 947	if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
 948		return TX_DROP;
 949
 950	mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie));
 951	mmie->element_id = WLAN_EID_MMIE;
 952	mmie->length = sizeof(*mmie) - 2;
 953	mmie->key_id = cpu_to_le16(key->conf.keyidx);
 954
 955	/* PN = PN + 1 */
 956	pn64 = atomic64_inc_return(&key->conf.tx_pn);
 957
 958	bip_ipn_set64(mmie->sequence_number, pn64);
 959
 
 
 
 960	bip_aad(skb, aad);
 961
 962	/*
 963	 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
 964	 */
 965	ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
 966			   skb->data + 24, skb->len - 24, mmie->mic);
 967
 968	return TX_CONTINUE;
 969}
 970
 971ieee80211_tx_result
 972ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx)
 973{
 974	struct sk_buff *skb;
 975	struct ieee80211_tx_info *info;
 976	struct ieee80211_key *key = tx->key;
 977	struct ieee80211_mmie_16 *mmie;
 978	u8 aad[20];
 979	u64 pn64;
 980
 981	if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
 982		return TX_DROP;
 983
 984	skb = skb_peek(&tx->skbs);
 985
 986	info = IEEE80211_SKB_CB(skb);
 987
 988	if (info->control.hw_key)
 989		return TX_CONTINUE;
 990
 991	if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
 992		return TX_DROP;
 993
 994	mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie));
 995	mmie->element_id = WLAN_EID_MMIE;
 996	mmie->length = sizeof(*mmie) - 2;
 997	mmie->key_id = cpu_to_le16(key->conf.keyidx);
 998
 999	/* PN = PN + 1 */
1000	pn64 = atomic64_inc_return(&key->conf.tx_pn);
1001
1002	bip_ipn_set64(mmie->sequence_number, pn64);
1003
1004	bip_aad(skb, aad);
1005
1006	/* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128)
1007	 */
1008	ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1009			       skb->data + 24, skb->len - 24, mmie->mic);
1010
1011	return TX_CONTINUE;
1012}
1013
1014ieee80211_rx_result
1015ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
1016{
1017	struct sk_buff *skb = rx->skb;
1018	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1019	struct ieee80211_key *key = rx->key;
1020	struct ieee80211_mmie *mmie;
1021	u8 aad[20], mic[8], ipn[6];
1022	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1023
1024	if (!ieee80211_is_mgmt(hdr->frame_control))
1025		return RX_CONTINUE;
1026
1027	/* management frames are already linear */
1028
1029	if (skb->len < 24 + sizeof(*mmie))
1030		return RX_DROP_UNUSABLE;
1031
1032	mmie = (struct ieee80211_mmie *)
1033		(skb->data + skb->len - sizeof(*mmie));
1034	if (mmie->element_id != WLAN_EID_MMIE ||
1035	    mmie->length != sizeof(*mmie) - 2)
1036		return RX_DROP_UNUSABLE; /* Invalid MMIE */
1037
1038	bip_ipn_swap(ipn, mmie->sequence_number);
1039
1040	if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1041		key->u.aes_cmac.replays++;
1042		return RX_DROP_UNUSABLE;
1043	}
1044
1045	if (!(status->flag & RX_FLAG_DECRYPTED)) {
1046		/* hardware didn't decrypt/verify MIC */
1047		bip_aad(skb, aad);
1048		ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
1049				   skb->data + 24, skb->len - 24, mic);
1050		if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1051			key->u.aes_cmac.icverrors++;
1052			return RX_DROP_UNUSABLE;
1053		}
1054	}
1055
1056	memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1057
1058	/* Remove MMIE */
1059	skb_trim(skb, skb->len - sizeof(*mmie));
1060
1061	return RX_CONTINUE;
1062}
1063
1064ieee80211_rx_result
1065ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
1066{
1067	struct sk_buff *skb = rx->skb;
1068	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1069	struct ieee80211_key *key = rx->key;
1070	struct ieee80211_mmie_16 *mmie;
1071	u8 aad[20], mic[16], ipn[6];
1072	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1073
1074	if (!ieee80211_is_mgmt(hdr->frame_control))
1075		return RX_CONTINUE;
1076
1077	/* management frames are already linear */
1078
1079	if (skb->len < 24 + sizeof(*mmie))
1080		return RX_DROP_UNUSABLE;
1081
1082	mmie = (struct ieee80211_mmie_16 *)
1083		(skb->data + skb->len - sizeof(*mmie));
1084	if (mmie->element_id != WLAN_EID_MMIE ||
1085	    mmie->length != sizeof(*mmie) - 2)
1086		return RX_DROP_UNUSABLE; /* Invalid MMIE */
1087
1088	bip_ipn_swap(ipn, mmie->sequence_number);
1089
1090	if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
1091		key->u.aes_cmac.replays++;
1092		return RX_DROP_UNUSABLE;
1093	}
1094
1095	if (!(status->flag & RX_FLAG_DECRYPTED)) {
1096		/* hardware didn't decrypt/verify MIC */
1097		bip_aad(skb, aad);
1098		ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
1099				       skb->data + 24, skb->len - 24, mic);
1100		if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1101			key->u.aes_cmac.icverrors++;
1102			return RX_DROP_UNUSABLE;
1103		}
1104	}
1105
1106	memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1107
1108	/* Remove MMIE */
1109	skb_trim(skb, skb->len - sizeof(*mmie));
1110
1111	return RX_CONTINUE;
1112}
1113
1114ieee80211_tx_result
1115ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx)
1116{
1117	struct sk_buff *skb;
1118	struct ieee80211_tx_info *info;
1119	struct ieee80211_key *key = tx->key;
1120	struct ieee80211_mmie_16 *mmie;
1121	struct ieee80211_hdr *hdr;
1122	u8 aad[GMAC_AAD_LEN];
1123	u64 pn64;
1124	u8 nonce[GMAC_NONCE_LEN];
1125
1126	if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
1127		return TX_DROP;
1128
1129	skb = skb_peek(&tx->skbs);
1130
1131	info = IEEE80211_SKB_CB(skb);
1132
1133	if (info->control.hw_key)
1134		return TX_CONTINUE;
1135
1136	if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
1137		return TX_DROP;
1138
1139	mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie));
1140	mmie->element_id = WLAN_EID_MMIE;
1141	mmie->length = sizeof(*mmie) - 2;
1142	mmie->key_id = cpu_to_le16(key->conf.keyidx);
1143
1144	/* PN = PN + 1 */
1145	pn64 = atomic64_inc_return(&key->conf.tx_pn);
1146
1147	bip_ipn_set64(mmie->sequence_number, pn64);
1148
1149	bip_aad(skb, aad);
1150
1151	hdr = (struct ieee80211_hdr *)skb->data;
1152	memcpy(nonce, hdr->addr2, ETH_ALEN);
1153	bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number);
1154
1155	/* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */
1156	if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1157			       skb->data + 24, skb->len - 24, mmie->mic) < 0)
1158		return TX_DROP;
1159
1160	return TX_CONTINUE;
1161}
1162
1163ieee80211_rx_result
1164ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx)
1165{
1166	struct sk_buff *skb = rx->skb;
1167	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1168	struct ieee80211_key *key = rx->key;
1169	struct ieee80211_mmie_16 *mmie;
1170	u8 aad[GMAC_AAD_LEN], mic[GMAC_MIC_LEN], ipn[6], nonce[GMAC_NONCE_LEN];
1171	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1172
1173	if (!ieee80211_is_mgmt(hdr->frame_control))
1174		return RX_CONTINUE;
1175
1176	/* management frames are already linear */
1177
1178	if (skb->len < 24 + sizeof(*mmie))
1179		return RX_DROP_UNUSABLE;
1180
1181	mmie = (struct ieee80211_mmie_16 *)
1182		(skb->data + skb->len - sizeof(*mmie));
1183	if (mmie->element_id != WLAN_EID_MMIE ||
1184	    mmie->length != sizeof(*mmie) - 2)
1185		return RX_DROP_UNUSABLE; /* Invalid MMIE */
1186
1187	bip_ipn_swap(ipn, mmie->sequence_number);
1188
1189	if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) {
1190		key->u.aes_gmac.replays++;
1191		return RX_DROP_UNUSABLE;
1192	}
1193
1194	if (!(status->flag & RX_FLAG_DECRYPTED)) {
1195		/* hardware didn't decrypt/verify MIC */
1196		bip_aad(skb, aad);
1197
1198		memcpy(nonce, hdr->addr2, ETH_ALEN);
1199		memcpy(nonce + ETH_ALEN, ipn, 6);
1200
 
 
 
1201		if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1202				       skb->data + 24, skb->len - 24,
1203				       mic) < 0 ||
1204		    memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
1205			key->u.aes_gmac.icverrors++;
1206			return RX_DROP_UNUSABLE;
 
1207		}
 
1208	}
1209
1210	memcpy(key->u.aes_gmac.rx_pn, ipn, 6);
1211
1212	/* Remove MMIE */
1213	skb_trim(skb, skb->len - sizeof(*mmie));
1214
1215	return RX_CONTINUE;
1216}
1217
1218ieee80211_tx_result
1219ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx)
1220{
1221	struct sk_buff *skb;
1222	struct ieee80211_tx_info *info = NULL;
1223	ieee80211_tx_result res;
1224
1225	skb_queue_walk(&tx->skbs, skb) {
1226		info  = IEEE80211_SKB_CB(skb);
1227
1228		/* handle hw-only algorithm */
1229		if (!info->control.hw_key)
1230			return TX_DROP;
1231
1232		if (tx->key->flags & KEY_FLAG_CIPHER_SCHEME) {
1233			res = ieee80211_crypto_cs_encrypt(tx, skb);
1234			if (res != TX_CONTINUE)
1235				return res;
1236		}
1237	}
1238
1239	ieee80211_tx_set_protected(tx);
1240
1241	return TX_CONTINUE;
1242}
1243
1244ieee80211_rx_result
1245ieee80211_crypto_hw_decrypt(struct ieee80211_rx_data *rx)
1246{
1247	if (rx->sta && rx->sta->cipher_scheme)
1248		return ieee80211_crypto_cs_decrypt(rx);
1249
1250	return RX_DROP_UNUSABLE;
1251}
v6.8
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright 2002-2004, Instant802 Networks, Inc.
   4 * Copyright 2008, Jouni Malinen <j@w1.fi>
   5 * Copyright (C) 2016-2017 Intel Deutschland GmbH
   6 * Copyright (C) 2020-2023 Intel Corporation
 
 
 
   7 */
   8
   9#include <linux/netdevice.h>
  10#include <linux/types.h>
  11#include <linux/skbuff.h>
  12#include <linux/compiler.h>
  13#include <linux/ieee80211.h>
  14#include <linux/gfp.h>
  15#include <asm/unaligned.h>
  16#include <net/mac80211.h>
  17#include <crypto/aes.h>
  18#include <crypto/utils.h>
  19
  20#include "ieee80211_i.h"
  21#include "michael.h"
  22#include "tkip.h"
  23#include "aes_ccm.h"
  24#include "aes_cmac.h"
  25#include "aes_gmac.h"
  26#include "aes_gcm.h"
  27#include "wpa.h"
  28
  29ieee80211_tx_result
  30ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
  31{
  32	u8 *data, *key, *mic;
  33	size_t data_len;
  34	unsigned int hdrlen;
  35	struct ieee80211_hdr *hdr;
  36	struct sk_buff *skb = tx->skb;
  37	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  38	int tail;
  39
  40	hdr = (struct ieee80211_hdr *)skb->data;
  41	if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
  42	    skb->len < 24 || !ieee80211_is_data_present(hdr->frame_control))
  43		return TX_CONTINUE;
  44
  45	hdrlen = ieee80211_hdrlen(hdr->frame_control);
  46	if (skb->len < hdrlen)
  47		return TX_DROP;
  48
  49	data = skb->data + hdrlen;
  50	data_len = skb->len - hdrlen;
  51
  52	if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) {
  53		/* Need to use software crypto for the test */
  54		info->control.hw_key = NULL;
  55	}
  56
  57	if (info->control.hw_key &&
  58	    (info->flags & IEEE80211_TX_CTL_DONTFRAG ||
  59	     ieee80211_hw_check(&tx->local->hw, SUPPORTS_TX_FRAG)) &&
  60	    !(tx->key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
  61				     IEEE80211_KEY_FLAG_PUT_MIC_SPACE))) {
  62		/* hwaccel - with no need for SW-generated MMIC or MIC space */
  63		return TX_CONTINUE;
  64	}
  65
  66	tail = MICHAEL_MIC_LEN;
  67	if (!info->control.hw_key)
  68		tail += IEEE80211_TKIP_ICV_LEN;
  69
  70	if (WARN(skb_tailroom(skb) < tail ||
  71		 skb_headroom(skb) < IEEE80211_TKIP_IV_LEN,
  72		 "mmic: not enough head/tail (%d/%d,%d/%d)\n",
  73		 skb_headroom(skb), IEEE80211_TKIP_IV_LEN,
  74		 skb_tailroom(skb), tail))
  75		return TX_DROP;
  76
 
  77	mic = skb_put(skb, MICHAEL_MIC_LEN);
  78
  79	if (tx->key->conf.flags & IEEE80211_KEY_FLAG_PUT_MIC_SPACE) {
  80		/* Zeroed MIC can help with debug */
  81		memset(mic, 0, MICHAEL_MIC_LEN);
  82		return TX_CONTINUE;
  83	}
  84
  85	key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY];
  86	michael_mic(key, hdr, data, data_len, mic);
  87	if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE))
  88		mic[0]++;
  89
  90	return TX_CONTINUE;
  91}
  92
  93
  94ieee80211_rx_result
  95ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
  96{
  97	u8 *data, *key = NULL;
  98	size_t data_len;
  99	unsigned int hdrlen;
 100	u8 mic[MICHAEL_MIC_LEN];
 101	struct sk_buff *skb = rx->skb;
 102	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 103	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 104
 105	/*
 106	 * it makes no sense to check for MIC errors on anything other
 107	 * than data frames.
 108	 */
 109	if (!ieee80211_is_data_present(hdr->frame_control))
 110		return RX_CONTINUE;
 111
 112	/*
 113	 * No way to verify the MIC if the hardware stripped it or
 114	 * the IV with the key index. In this case we have solely rely
 115	 * on the driver to set RX_FLAG_MMIC_ERROR in the event of a
 116	 * MIC failure report.
 117	 */
 118	if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) {
 119		if (status->flag & RX_FLAG_MMIC_ERROR)
 120			goto mic_fail_no_key;
 121
 122		if (!(status->flag & RX_FLAG_IV_STRIPPED) && rx->key &&
 123		    rx->key->conf.cipher == WLAN_CIPHER_SUITE_TKIP)
 124			goto update_iv;
 125
 126		return RX_CONTINUE;
 127	}
 128
 129	/*
 130	 * Some hardware seems to generate Michael MIC failure reports; even
 131	 * though, the frame was not encrypted with TKIP and therefore has no
 132	 * MIC. Ignore the flag them to avoid triggering countermeasures.
 133	 */
 134	if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
 135	    !(status->flag & RX_FLAG_DECRYPTED))
 136		return RX_CONTINUE;
 137
 138	if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) {
 139		/*
 140		 * APs with pairwise keys should never receive Michael MIC
 141		 * errors for non-zero keyidx because these are reserved for
 142		 * group keys and only the AP is sending real multicast
 143		 * frames in the BSS.
 144		 */
 145		return RX_DROP_U_AP_RX_GROUPCAST;
 146	}
 147
 148	if (status->flag & RX_FLAG_MMIC_ERROR)
 149		goto mic_fail;
 150
 151	hdrlen = ieee80211_hdrlen(hdr->frame_control);
 152	if (skb->len < hdrlen + MICHAEL_MIC_LEN)
 153		return RX_DROP_U_SHORT_MMIC;
 154
 155	if (skb_linearize(rx->skb))
 156		return RX_DROP_U_OOM;
 157	hdr = (void *)skb->data;
 158
 159	data = skb->data + hdrlen;
 160	data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
 161	key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY];
 162	michael_mic(key, hdr, data, data_len, mic);
 163	if (crypto_memneq(mic, data + data_len, MICHAEL_MIC_LEN))
 164		goto mic_fail;
 165
 166	/* remove Michael MIC from payload */
 167	skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
 168
 169update_iv:
 170	/* update IV in key information to be able to detect replays */
 171	rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip.iv32;
 172	rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip.iv16;
 173
 174	return RX_CONTINUE;
 175
 176mic_fail:
 177	rx->key->u.tkip.mic_failures++;
 178
 179mic_fail_no_key:
 180	/*
 181	 * In some cases the key can be unset - e.g. a multicast packet, in
 182	 * a driver that supports HW encryption. Send up the key idx only if
 183	 * the key is set.
 184	 */
 185	cfg80211_michael_mic_failure(rx->sdata->dev, hdr->addr2,
 186				     is_multicast_ether_addr(hdr->addr1) ?
 187				     NL80211_KEYTYPE_GROUP :
 188				     NL80211_KEYTYPE_PAIRWISE,
 189				     rx->key ? rx->key->conf.keyidx : -1,
 190				     NULL, GFP_ATOMIC);
 191	return RX_DROP_U_MMIC_FAIL;
 192}
 193
 194static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
 195{
 196	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 197	struct ieee80211_key *key = tx->key;
 198	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 199	unsigned int hdrlen;
 200	int len, tail;
 201	u64 pn;
 202	u8 *pos;
 203
 204	if (info->control.hw_key &&
 205	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 206	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
 207		/* hwaccel - with no need for software-generated IV */
 208		return 0;
 209	}
 210
 211	hdrlen = ieee80211_hdrlen(hdr->frame_control);
 212	len = skb->len - hdrlen;
 213
 214	if (info->control.hw_key)
 215		tail = 0;
 216	else
 217		tail = IEEE80211_TKIP_ICV_LEN;
 218
 219	if (WARN_ON(skb_tailroom(skb) < tail ||
 220		    skb_headroom(skb) < IEEE80211_TKIP_IV_LEN))
 221		return -1;
 222
 223	pos = skb_push(skb, IEEE80211_TKIP_IV_LEN);
 224	memmove(pos, pos + IEEE80211_TKIP_IV_LEN, hdrlen);
 225	pos += hdrlen;
 226
 227	/* the HW only needs room for the IV, but not the actual IV */
 228	if (info->control.hw_key &&
 229	    (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 230		return 0;
 231
 232	/* Increase IV for the frame */
 233	pn = atomic64_inc_return(&key->conf.tx_pn);
 234	pos = ieee80211_tkip_add_iv(pos, &key->conf, pn);
 235
 236	/* hwaccel - with software IV */
 237	if (info->control.hw_key)
 238		return 0;
 239
 240	/* Add room for ICV */
 241	skb_put(skb, IEEE80211_TKIP_ICV_LEN);
 242
 243	return ieee80211_tkip_encrypt_data(&tx->local->wep_tx_ctx,
 244					   key, skb, pos, len);
 245}
 246
 247
 248ieee80211_tx_result
 249ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
 250{
 251	struct sk_buff *skb;
 252
 253	ieee80211_tx_set_protected(tx);
 254
 255	skb_queue_walk(&tx->skbs, skb) {
 256		if (tkip_encrypt_skb(tx, skb) < 0)
 257			return TX_DROP;
 258	}
 259
 260	return TX_CONTINUE;
 261}
 262
 263
 264ieee80211_rx_result
 265ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
 266{
 267	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
 268	int hdrlen, res, hwaccel = 0;
 269	struct ieee80211_key *key = rx->key;
 270	struct sk_buff *skb = rx->skb;
 271	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 272
 273	hdrlen = ieee80211_hdrlen(hdr->frame_control);
 274
 275	if (!ieee80211_is_data(hdr->frame_control))
 276		return RX_CONTINUE;
 277
 278	if (!rx->sta || skb->len - hdrlen < 12)
 279		return RX_DROP_U_SHORT_TKIP;
 280
 281	/* it may be possible to optimize this a bit more */
 282	if (skb_linearize(rx->skb))
 283		return RX_DROP_U_OOM;
 284	hdr = (void *)skb->data;
 285
 286	/*
 287	 * Let TKIP code verify IV, but skip decryption.
 288	 * In the case where hardware checks the IV as well,
 289	 * we don't even get here, see ieee80211_rx_h_decrypt()
 290	 */
 291	if (status->flag & RX_FLAG_DECRYPTED)
 292		hwaccel = 1;
 293
 294	res = ieee80211_tkip_decrypt_data(&rx->local->wep_rx_ctx,
 295					  key, skb->data + hdrlen,
 296					  skb->len - hdrlen, rx->sta->sta.addr,
 297					  hdr->addr1, hwaccel, rx->security_idx,
 298					  &rx->tkip.iv32,
 299					  &rx->tkip.iv16);
 300	if (res != TKIP_DECRYPT_OK)
 301		return RX_DROP_U_TKIP_FAIL;
 302
 303	/* Trim ICV */
 304	if (!(status->flag & RX_FLAG_ICV_STRIPPED))
 305		skb_trim(skb, skb->len - IEEE80211_TKIP_ICV_LEN);
 306
 307	/* Remove IV */
 308	memmove(skb->data + IEEE80211_TKIP_IV_LEN, skb->data, hdrlen);
 309	skb_pull(skb, IEEE80211_TKIP_IV_LEN);
 310
 311	return RX_CONTINUE;
 312}
 313
 314/*
 315 * Calculate AAD for CCMP/GCMP, returning qos_tid since we
 316 * need that in CCMP also for b_0.
 317 */
 318static u8 ccmp_gcmp_aad(struct sk_buff *skb, u8 *aad)
 319{
 320	struct ieee80211_hdr *hdr = (void *)skb->data;
 321	__le16 mask_fc;
 322	int a4_included, mgmt;
 323	u8 qos_tid;
 324	u16 len_a = 22;
 
 
 325
 326	/*
 327	 * Mask FC: zero subtype b4 b5 b6 (if not mgmt)
 328	 * Retry, PwrMgt, MoreData, Order (if Qos Data); set Protected
 329	 */
 330	mgmt = ieee80211_is_mgmt(hdr->frame_control);
 331	mask_fc = hdr->frame_control;
 332	mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
 333				IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
 334	if (!mgmt)
 335		mask_fc &= ~cpu_to_le16(0x0070);
 336	mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
 337
 
 
 338	a4_included = ieee80211_has_a4(hdr->frame_control);
 339	if (a4_included)
 340		len_a += 6;
 341
 342	if (ieee80211_is_data_qos(hdr->frame_control)) {
 343		qos_tid = ieee80211_get_tid(hdr);
 344		mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_ORDER);
 345		len_a += 2;
 346	} else {
 347		qos_tid = 0;
 348	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 349
 350	/* AAD (extra authenticate-only data) / masked 802.11 header
 351	 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */
 352	put_unaligned_be16(len_a, &aad[0]);
 353	put_unaligned(mask_fc, (__le16 *)&aad[2]);
 354	memcpy(&aad[4], &hdr->addrs, 3 * ETH_ALEN);
 355
 356	/* Mask Seq#, leave Frag# */
 357	aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
 358	aad[23] = 0;
 359
 360	if (a4_included) {
 361		memcpy(&aad[24], hdr->addr4, ETH_ALEN);
 362		aad[30] = qos_tid;
 363		aad[31] = 0;
 364	} else {
 365		memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
 366		aad[24] = qos_tid;
 367	}
 368
 369	return qos_tid;
 370}
 371
 372static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad)
 373{
 374	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 375	u8 qos_tid = ccmp_gcmp_aad(skb, aad);
 376
 377	/* In CCM, the initial vectors (IV) used for CTR mode encryption and CBC
 378	 * mode authentication are not allowed to collide, yet both are derived
 379	 * from this vector b_0. We only set L := 1 here to indicate that the
 380	 * data size can be represented in (L+1) bytes. The CCM layer will take
 381	 * care of storing the data length in the top (L+1) bytes and setting
 382	 * and clearing the other bits as is required to derive the two IVs.
 383	 */
 384	b_0[0] = 0x1;
 385
 386	/* Nonce: Nonce Flags | A2 | PN
 387	 * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7)
 388	 */
 389	b_0[1] = qos_tid | (ieee80211_is_mgmt(hdr->frame_control) << 4);
 390	memcpy(&b_0[2], hdr->addr2, ETH_ALEN);
 391	memcpy(&b_0[8], pn, IEEE80211_CCMP_PN_LEN);
 392}
 393
 394static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
 395{
 396	hdr[0] = pn[5];
 397	hdr[1] = pn[4];
 398	hdr[2] = 0;
 399	hdr[3] = 0x20 | (key_id << 6);
 400	hdr[4] = pn[3];
 401	hdr[5] = pn[2];
 402	hdr[6] = pn[1];
 403	hdr[7] = pn[0];
 404}
 405
 406
 407static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr)
 408{
 409	pn[0] = hdr[7];
 410	pn[1] = hdr[6];
 411	pn[2] = hdr[5];
 412	pn[3] = hdr[4];
 413	pn[4] = hdr[1];
 414	pn[5] = hdr[0];
 415}
 416
 417
 418static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb,
 419			    unsigned int mic_len)
 420{
 421	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 422	struct ieee80211_key *key = tx->key;
 423	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 424	int hdrlen, len, tail;
 425	u8 *pos;
 426	u8 pn[6];
 427	u64 pn64;
 428	u8 aad[CCM_AAD_LEN];
 429	u8 b_0[AES_BLOCK_SIZE];
 430
 431	if (info->control.hw_key &&
 432	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 433	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 434	    !((info->control.hw_key->flags &
 435	       IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
 436	      ieee80211_is_mgmt(hdr->frame_control))) {
 437		/*
 438		 * hwaccel has no need for preallocated room for CCMP
 439		 * header or MIC fields
 440		 */
 441		return 0;
 442	}
 443
 444	hdrlen = ieee80211_hdrlen(hdr->frame_control);
 445	len = skb->len - hdrlen;
 446
 447	if (info->control.hw_key)
 448		tail = 0;
 449	else
 450		tail = mic_len;
 451
 452	if (WARN_ON(skb_tailroom(skb) < tail ||
 453		    skb_headroom(skb) < IEEE80211_CCMP_HDR_LEN))
 454		return -1;
 455
 456	pos = skb_push(skb, IEEE80211_CCMP_HDR_LEN);
 457	memmove(pos, pos + IEEE80211_CCMP_HDR_LEN, hdrlen);
 458
 459	/* the HW only needs room for the IV, but not the actual IV */
 460	if (info->control.hw_key &&
 461	    (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 462		return 0;
 463
 
 464	pos += hdrlen;
 465
 466	pn64 = atomic64_inc_return(&key->conf.tx_pn);
 467
 468	pn[5] = pn64;
 469	pn[4] = pn64 >> 8;
 470	pn[3] = pn64 >> 16;
 471	pn[2] = pn64 >> 24;
 472	pn[1] = pn64 >> 32;
 473	pn[0] = pn64 >> 40;
 474
 475	ccmp_pn2hdr(pos, pn, key->conf.keyidx);
 476
 477	/* hwaccel - with software CCMP header */
 478	if (info->control.hw_key)
 479		return 0;
 480
 481	pos += IEEE80211_CCMP_HDR_LEN;
 482	ccmp_special_blocks(skb, pn, b_0, aad);
 483	return ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, b_0, aad, pos, len,
 484					 skb_put(skb, mic_len));
 485}
 486
 487
 488ieee80211_tx_result
 489ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx,
 490			      unsigned int mic_len)
 491{
 492	struct sk_buff *skb;
 493
 494	ieee80211_tx_set_protected(tx);
 495
 496	skb_queue_walk(&tx->skbs, skb) {
 497		if (ccmp_encrypt_skb(tx, skb, mic_len) < 0)
 498			return TX_DROP;
 499	}
 500
 501	return TX_CONTINUE;
 502}
 503
 504
 505ieee80211_rx_result
 506ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx,
 507			      unsigned int mic_len)
 508{
 509	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 510	int hdrlen;
 511	struct ieee80211_key *key = rx->key;
 512	struct sk_buff *skb = rx->skb;
 513	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 514	u8 pn[IEEE80211_CCMP_PN_LEN];
 515	int data_len;
 516	int queue;
 517
 518	hdrlen = ieee80211_hdrlen(hdr->frame_control);
 519
 520	if (!ieee80211_is_data(hdr->frame_control) &&
 521	    !ieee80211_is_robust_mgmt_frame(skb))
 522		return RX_CONTINUE;
 523
 524	if (status->flag & RX_FLAG_DECRYPTED) {
 525		if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_CCMP_HDR_LEN))
 526			return RX_DROP_U_SHORT_CCMP;
 527		if (status->flag & RX_FLAG_MIC_STRIPPED)
 528			mic_len = 0;
 529	} else {
 530		if (skb_linearize(rx->skb))
 531			return RX_DROP_U_OOM;
 532	}
 533
 534	/* reload hdr - skb might have been reallocated */
 535	hdr = (void *)rx->skb->data;
 536
 537	data_len = skb->len - hdrlen - IEEE80211_CCMP_HDR_LEN - mic_len;
 538	if (!rx->sta || data_len < 0)
 539		return RX_DROP_U_SHORT_CCMP;
 540
 541	if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
 542		int res;
 543
 544		ccmp_hdr2pn(pn, skb->data + hdrlen);
 545
 546		queue = rx->security_idx;
 547
 548		res = memcmp(pn, key->u.ccmp.rx_pn[queue],
 549			     IEEE80211_CCMP_PN_LEN);
 550		if (res < 0 ||
 551		    (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
 552			key->u.ccmp.replays++;
 553			return RX_DROP_U_REPLAY;
 554		}
 555
 556		if (!(status->flag & RX_FLAG_DECRYPTED)) {
 557			u8 aad[2 * AES_BLOCK_SIZE];
 558			u8 b_0[AES_BLOCK_SIZE];
 559			/* hardware didn't decrypt/verify MIC */
 560			ccmp_special_blocks(skb, pn, b_0, aad);
 561
 562			if (ieee80211_aes_ccm_decrypt(
 563				    key->u.ccmp.tfm, b_0, aad,
 564				    skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN,
 565				    data_len,
 566				    skb->data + skb->len - mic_len))
 567				return RX_DROP_U_MIC_FAIL;
 568		}
 569
 570		memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN);
 571		if (unlikely(ieee80211_is_frag(hdr)))
 572			memcpy(rx->ccm_gcm.pn, pn, IEEE80211_CCMP_PN_LEN);
 573	}
 574
 575	/* Remove CCMP header and MIC */
 576	if (pskb_trim(skb, skb->len - mic_len))
 577		return RX_DROP_U_SHORT_CCMP_MIC;
 578	memmove(skb->data + IEEE80211_CCMP_HDR_LEN, skb->data, hdrlen);
 579	skb_pull(skb, IEEE80211_CCMP_HDR_LEN);
 580
 581	return RX_CONTINUE;
 582}
 583
 584static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad)
 585{
 586	struct ieee80211_hdr *hdr = (void *)skb->data;
 
 
 587
 588	memcpy(j_0, hdr->addr2, ETH_ALEN);
 589	memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN);
 590	j_0[13] = 0;
 591	j_0[14] = 0;
 592	j_0[AES_BLOCK_SIZE - 1] = 0x01;
 593
 594	ccmp_gcmp_aad(skb, aad);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 595}
 596
 597static inline void gcmp_pn2hdr(u8 *hdr, const u8 *pn, int key_id)
 598{
 599	hdr[0] = pn[5];
 600	hdr[1] = pn[4];
 601	hdr[2] = 0;
 602	hdr[3] = 0x20 | (key_id << 6);
 603	hdr[4] = pn[3];
 604	hdr[5] = pn[2];
 605	hdr[6] = pn[1];
 606	hdr[7] = pn[0];
 607}
 608
 609static inline void gcmp_hdr2pn(u8 *pn, const u8 *hdr)
 610{
 611	pn[0] = hdr[7];
 612	pn[1] = hdr[6];
 613	pn[2] = hdr[5];
 614	pn[3] = hdr[4];
 615	pn[4] = hdr[1];
 616	pn[5] = hdr[0];
 617}
 618
 619static int gcmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
 620{
 621	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 622	struct ieee80211_key *key = tx->key;
 623	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 624	int hdrlen, len, tail;
 625	u8 *pos;
 626	u8 pn[6];
 627	u64 pn64;
 628	u8 aad[GCM_AAD_LEN];
 629	u8 j_0[AES_BLOCK_SIZE];
 630
 631	if (info->control.hw_key &&
 632	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
 633	    !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 634	    !((info->control.hw_key->flags &
 635	       IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
 636	      ieee80211_is_mgmt(hdr->frame_control))) {
 637		/* hwaccel has no need for preallocated room for GCMP
 638		 * header or MIC fields
 639		 */
 640		return 0;
 641	}
 642
 643	hdrlen = ieee80211_hdrlen(hdr->frame_control);
 644	len = skb->len - hdrlen;
 645
 646	if (info->control.hw_key)
 647		tail = 0;
 648	else
 649		tail = IEEE80211_GCMP_MIC_LEN;
 650
 651	if (WARN_ON(skb_tailroom(skb) < tail ||
 652		    skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN))
 653		return -1;
 654
 655	pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN);
 656	memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen);
 657	skb_set_network_header(skb, skb_network_offset(skb) +
 658				    IEEE80211_GCMP_HDR_LEN);
 659
 660	/* the HW only needs room for the IV, but not the actual IV */
 661	if (info->control.hw_key &&
 662	    (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
 663		return 0;
 664
 
 665	pos += hdrlen;
 666
 667	pn64 = atomic64_inc_return(&key->conf.tx_pn);
 668
 669	pn[5] = pn64;
 670	pn[4] = pn64 >> 8;
 671	pn[3] = pn64 >> 16;
 672	pn[2] = pn64 >> 24;
 673	pn[1] = pn64 >> 32;
 674	pn[0] = pn64 >> 40;
 675
 676	gcmp_pn2hdr(pos, pn, key->conf.keyidx);
 677
 678	/* hwaccel - with software GCMP header */
 679	if (info->control.hw_key)
 680		return 0;
 681
 682	pos += IEEE80211_GCMP_HDR_LEN;
 683	gcmp_special_blocks(skb, pn, j_0, aad);
 684	return ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len,
 685					 skb_put(skb, IEEE80211_GCMP_MIC_LEN));
 686}
 687
 688ieee80211_tx_result
 689ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx)
 690{
 691	struct sk_buff *skb;
 692
 693	ieee80211_tx_set_protected(tx);
 694
 695	skb_queue_walk(&tx->skbs, skb) {
 696		if (gcmp_encrypt_skb(tx, skb) < 0)
 697			return TX_DROP;
 698	}
 699
 700	return TX_CONTINUE;
 701}
 702
 703ieee80211_rx_result
 704ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
 705{
 706	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
 707	int hdrlen;
 708	struct ieee80211_key *key = rx->key;
 709	struct sk_buff *skb = rx->skb;
 710	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 711	u8 pn[IEEE80211_GCMP_PN_LEN];
 712	int data_len, queue, mic_len = IEEE80211_GCMP_MIC_LEN;
 713
 714	hdrlen = ieee80211_hdrlen(hdr->frame_control);
 715
 716	if (!ieee80211_is_data(hdr->frame_control) &&
 717	    !ieee80211_is_robust_mgmt_frame(skb))
 718		return RX_CONTINUE;
 719
 720	if (status->flag & RX_FLAG_DECRYPTED) {
 721		if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN))
 722			return RX_DROP_U_SHORT_GCMP;
 723		if (status->flag & RX_FLAG_MIC_STRIPPED)
 724			mic_len = 0;
 725	} else {
 726		if (skb_linearize(rx->skb))
 727			return RX_DROP_U_OOM;
 728	}
 729
 730	/* reload hdr - skb might have been reallocated */
 731	hdr = (void *)rx->skb->data;
 732
 733	data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN - mic_len;
 734	if (!rx->sta || data_len < 0)
 735		return RX_DROP_U_SHORT_GCMP;
 736
 737	if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
 738		int res;
 739
 740		gcmp_hdr2pn(pn, skb->data + hdrlen);
 741
 742		queue = rx->security_idx;
 743
 744		res = memcmp(pn, key->u.gcmp.rx_pn[queue],
 745			     IEEE80211_GCMP_PN_LEN);
 746		if (res < 0 ||
 747		    (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
 748			key->u.gcmp.replays++;
 749			return RX_DROP_U_REPLAY;
 750		}
 751
 752		if (!(status->flag & RX_FLAG_DECRYPTED)) {
 753			u8 aad[2 * AES_BLOCK_SIZE];
 754			u8 j_0[AES_BLOCK_SIZE];
 755			/* hardware didn't decrypt/verify MIC */
 756			gcmp_special_blocks(skb, pn, j_0, aad);
 757
 758			if (ieee80211_aes_gcm_decrypt(
 759				    key->u.gcmp.tfm, j_0, aad,
 760				    skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN,
 761				    data_len,
 762				    skb->data + skb->len -
 763				    IEEE80211_GCMP_MIC_LEN))
 764				return RX_DROP_U_MIC_FAIL;
 765		}
 766
 767		memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN);
 768		if (unlikely(ieee80211_is_frag(hdr)))
 769			memcpy(rx->ccm_gcm.pn, pn, IEEE80211_CCMP_PN_LEN);
 770	}
 771
 772	/* Remove GCMP header and MIC */
 773	if (pskb_trim(skb, skb->len - mic_len))
 774		return RX_DROP_U_SHORT_GCMP_MIC;
 775	memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen);
 776	skb_pull(skb, IEEE80211_GCMP_HDR_LEN);
 777
 778	return RX_CONTINUE;
 779}
 780
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 781static void bip_aad(struct sk_buff *skb, u8 *aad)
 782{
 783	__le16 mask_fc;
 784	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 785
 786	/* BIP AAD: FC(masked) || A1 || A2 || A3 */
 787
 788	/* FC type/subtype */
 789	/* Mask FC Retry, PwrMgt, MoreData flags to zero */
 790	mask_fc = hdr->frame_control;
 791	mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY | IEEE80211_FCTL_PM |
 792				IEEE80211_FCTL_MOREDATA);
 793	put_unaligned(mask_fc, (__le16 *) &aad[0]);
 794	/* A1 || A2 || A3 */
 795	memcpy(aad + 2, &hdr->addrs, 3 * ETH_ALEN);
 796}
 797
 798
 799static inline void bip_ipn_set64(u8 *d, u64 pn)
 800{
 801	*d++ = pn;
 802	*d++ = pn >> 8;
 803	*d++ = pn >> 16;
 804	*d++ = pn >> 24;
 805	*d++ = pn >> 32;
 806	*d = pn >> 40;
 807}
 808
 809static inline void bip_ipn_swap(u8 *d, const u8 *s)
 810{
 811	*d++ = s[5];
 812	*d++ = s[4];
 813	*d++ = s[3];
 814	*d++ = s[2];
 815	*d++ = s[1];
 816	*d = s[0];
 817}
 818
 819
 820ieee80211_tx_result
 821ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
 822{
 823	struct sk_buff *skb;
 824	struct ieee80211_tx_info *info;
 825	struct ieee80211_key *key = tx->key;
 826	struct ieee80211_mmie *mmie;
 827	u8 aad[20];
 828	u64 pn64;
 829
 830	if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
 831		return TX_DROP;
 832
 833	skb = skb_peek(&tx->skbs);
 834
 835	info = IEEE80211_SKB_CB(skb);
 836
 837	if (info->control.hw_key &&
 838	    !(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIE))
 839		return TX_CONTINUE;
 840
 841	if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
 842		return TX_DROP;
 843
 844	mmie = skb_put(skb, sizeof(*mmie));
 845	mmie->element_id = WLAN_EID_MMIE;
 846	mmie->length = sizeof(*mmie) - 2;
 847	mmie->key_id = cpu_to_le16(key->conf.keyidx);
 848
 849	/* PN = PN + 1 */
 850	pn64 = atomic64_inc_return(&key->conf.tx_pn);
 851
 852	bip_ipn_set64(mmie->sequence_number, pn64);
 853
 854	if (info->control.hw_key)
 855		return TX_CONTINUE;
 856
 857	bip_aad(skb, aad);
 858
 859	/*
 860	 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
 861	 */
 862	ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
 863			   skb->data + 24, skb->len - 24, mmie->mic);
 864
 865	return TX_CONTINUE;
 866}
 867
 868ieee80211_tx_result
 869ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx)
 870{
 871	struct sk_buff *skb;
 872	struct ieee80211_tx_info *info;
 873	struct ieee80211_key *key = tx->key;
 874	struct ieee80211_mmie_16 *mmie;
 875	u8 aad[20];
 876	u64 pn64;
 877
 878	if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
 879		return TX_DROP;
 880
 881	skb = skb_peek(&tx->skbs);
 882
 883	info = IEEE80211_SKB_CB(skb);
 884
 885	if (info->control.hw_key)
 886		return TX_CONTINUE;
 887
 888	if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
 889		return TX_DROP;
 890
 891	mmie = skb_put(skb, sizeof(*mmie));
 892	mmie->element_id = WLAN_EID_MMIE;
 893	mmie->length = sizeof(*mmie) - 2;
 894	mmie->key_id = cpu_to_le16(key->conf.keyidx);
 895
 896	/* PN = PN + 1 */
 897	pn64 = atomic64_inc_return(&key->conf.tx_pn);
 898
 899	bip_ipn_set64(mmie->sequence_number, pn64);
 900
 901	bip_aad(skb, aad);
 902
 903	/* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128)
 904	 */
 905	ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
 906			       skb->data + 24, skb->len - 24, mmie->mic);
 907
 908	return TX_CONTINUE;
 909}
 910
 911ieee80211_rx_result
 912ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
 913{
 914	struct sk_buff *skb = rx->skb;
 915	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 916	struct ieee80211_key *key = rx->key;
 917	struct ieee80211_mmie *mmie;
 918	u8 aad[20], mic[8], ipn[6];
 919	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 920
 921	if (!ieee80211_is_mgmt(hdr->frame_control))
 922		return RX_CONTINUE;
 923
 924	/* management frames are already linear */
 925
 926	if (skb->len < 24 + sizeof(*mmie))
 927		return RX_DROP_U_SHORT_CMAC;
 928
 929	mmie = (struct ieee80211_mmie *)
 930		(skb->data + skb->len - sizeof(*mmie));
 931	if (mmie->element_id != WLAN_EID_MMIE ||
 932	    mmie->length != sizeof(*mmie) - 2)
 933		return RX_DROP_U_BAD_MMIE; /* Invalid MMIE */
 934
 935	bip_ipn_swap(ipn, mmie->sequence_number);
 936
 937	if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
 938		key->u.aes_cmac.replays++;
 939		return RX_DROP_U_REPLAY;
 940	}
 941
 942	if (!(status->flag & RX_FLAG_DECRYPTED)) {
 943		/* hardware didn't decrypt/verify MIC */
 944		bip_aad(skb, aad);
 945		ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
 946				   skb->data + 24, skb->len - 24, mic);
 947		if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
 948			key->u.aes_cmac.icverrors++;
 949			return RX_DROP_U_MIC_FAIL;
 950		}
 951	}
 952
 953	memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
 954
 955	/* Remove MMIE */
 956	skb_trim(skb, skb->len - sizeof(*mmie));
 957
 958	return RX_CONTINUE;
 959}
 960
 961ieee80211_rx_result
 962ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
 963{
 964	struct sk_buff *skb = rx->skb;
 965	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
 966	struct ieee80211_key *key = rx->key;
 967	struct ieee80211_mmie_16 *mmie;
 968	u8 aad[20], mic[16], ipn[6];
 969	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 970
 971	if (!ieee80211_is_mgmt(hdr->frame_control))
 972		return RX_CONTINUE;
 973
 974	/* management frames are already linear */
 975
 976	if (skb->len < 24 + sizeof(*mmie))
 977		return RX_DROP_U_SHORT_CMAC256;
 978
 979	mmie = (struct ieee80211_mmie_16 *)
 980		(skb->data + skb->len - sizeof(*mmie));
 981	if (mmie->element_id != WLAN_EID_MMIE ||
 982	    mmie->length != sizeof(*mmie) - 2)
 983		return RX_DROP_U_BAD_MMIE; /* Invalid MMIE */
 984
 985	bip_ipn_swap(ipn, mmie->sequence_number);
 986
 987	if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
 988		key->u.aes_cmac.replays++;
 989		return RX_DROP_U_REPLAY;
 990	}
 991
 992	if (!(status->flag & RX_FLAG_DECRYPTED)) {
 993		/* hardware didn't decrypt/verify MIC */
 994		bip_aad(skb, aad);
 995		ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad,
 996				       skb->data + 24, skb->len - 24, mic);
 997		if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
 998			key->u.aes_cmac.icverrors++;
 999			return RX_DROP_U_MIC_FAIL;
1000		}
1001	}
1002
1003	memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
1004
1005	/* Remove MMIE */
1006	skb_trim(skb, skb->len - sizeof(*mmie));
1007
1008	return RX_CONTINUE;
1009}
1010
1011ieee80211_tx_result
1012ieee80211_crypto_aes_gmac_encrypt(struct ieee80211_tx_data *tx)
1013{
1014	struct sk_buff *skb;
1015	struct ieee80211_tx_info *info;
1016	struct ieee80211_key *key = tx->key;
1017	struct ieee80211_mmie_16 *mmie;
1018	struct ieee80211_hdr *hdr;
1019	u8 aad[GMAC_AAD_LEN];
1020	u64 pn64;
1021	u8 nonce[GMAC_NONCE_LEN];
1022
1023	if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
1024		return TX_DROP;
1025
1026	skb = skb_peek(&tx->skbs);
1027
1028	info = IEEE80211_SKB_CB(skb);
1029
1030	if (info->control.hw_key)
1031		return TX_CONTINUE;
1032
1033	if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
1034		return TX_DROP;
1035
1036	mmie = skb_put(skb, sizeof(*mmie));
1037	mmie->element_id = WLAN_EID_MMIE;
1038	mmie->length = sizeof(*mmie) - 2;
1039	mmie->key_id = cpu_to_le16(key->conf.keyidx);
1040
1041	/* PN = PN + 1 */
1042	pn64 = atomic64_inc_return(&key->conf.tx_pn);
1043
1044	bip_ipn_set64(mmie->sequence_number, pn64);
1045
1046	bip_aad(skb, aad);
1047
1048	hdr = (struct ieee80211_hdr *)skb->data;
1049	memcpy(nonce, hdr->addr2, ETH_ALEN);
1050	bip_ipn_swap(nonce + ETH_ALEN, mmie->sequence_number);
1051
1052	/* MIC = AES-GMAC(IGTK, AAD || Management Frame Body || MMIE, 128) */
1053	if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1054			       skb->data + 24, skb->len - 24, mmie->mic) < 0)
1055		return TX_DROP;
1056
1057	return TX_CONTINUE;
1058}
1059
1060ieee80211_rx_result
1061ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx)
1062{
1063	struct sk_buff *skb = rx->skb;
1064	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
1065	struct ieee80211_key *key = rx->key;
1066	struct ieee80211_mmie_16 *mmie;
1067	u8 aad[GMAC_AAD_LEN], *mic, ipn[6], nonce[GMAC_NONCE_LEN];
1068	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1069
1070	if (!ieee80211_is_mgmt(hdr->frame_control))
1071		return RX_CONTINUE;
1072
1073	/* management frames are already linear */
1074
1075	if (skb->len < 24 + sizeof(*mmie))
1076		return RX_DROP_U_SHORT_GMAC;
1077
1078	mmie = (struct ieee80211_mmie_16 *)
1079		(skb->data + skb->len - sizeof(*mmie));
1080	if (mmie->element_id != WLAN_EID_MMIE ||
1081	    mmie->length != sizeof(*mmie) - 2)
1082		return RX_DROP_U_BAD_MMIE; /* Invalid MMIE */
1083
1084	bip_ipn_swap(ipn, mmie->sequence_number);
1085
1086	if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) {
1087		key->u.aes_gmac.replays++;
1088		return RX_DROP_U_REPLAY;
1089	}
1090
1091	if (!(status->flag & RX_FLAG_DECRYPTED)) {
1092		/* hardware didn't decrypt/verify MIC */
1093		bip_aad(skb, aad);
1094
1095		memcpy(nonce, hdr->addr2, ETH_ALEN);
1096		memcpy(nonce + ETH_ALEN, ipn, 6);
1097
1098		mic = kmalloc(GMAC_MIC_LEN, GFP_ATOMIC);
1099		if (!mic)
1100			return RX_DROP_U_OOM;
1101		if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce,
1102				       skb->data + 24, skb->len - 24,
1103				       mic) < 0 ||
1104		    crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
1105			key->u.aes_gmac.icverrors++;
1106			kfree(mic);
1107			return RX_DROP_U_MIC_FAIL;
1108		}
1109		kfree(mic);
1110	}
1111
1112	memcpy(key->u.aes_gmac.rx_pn, ipn, 6);
1113
1114	/* Remove MMIE */
1115	skb_trim(skb, skb->len - sizeof(*mmie));
1116
1117	return RX_CONTINUE;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1118}