blob: bdb53aba888e147cfd3bae984cd69811f520261a [file] [log] [blame]
Jiri Bencf0706e82007-05-05 11:45:53 -07001/*
2 * Copyright 2002-2004, Instant802 Networks, Inc.
Jouni Malinen765cb462009-01-08 13:32:01 +02003 * Copyright 2008, Jouni Malinen <j@w1.fi>
Jiri Bencf0706e82007-05-05 11:45:53 -07004 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 */
9
10#include <linux/netdevice.h>
11#include <linux/types.h>
Jiri Bencf0706e82007-05-05 11:45:53 -070012#include <linux/skbuff.h>
13#include <linux/compiler.h>
Harvey Harrisonf14df802008-07-02 11:05:35 -070014#include <linux/ieee80211.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090015#include <linux/gfp.h>
Harvey Harrisonf14df802008-07-02 11:05:35 -070016#include <asm/unaligned.h>
Jiri Bencf0706e82007-05-05 11:45:53 -070017#include <net/mac80211.h>
Johannes Bergaba83a0b2011-07-06 21:59:39 +020018#include <crypto/aes.h>
Johannes Bergeb063c12007-08-28 17:01:53 -040019
Jiri Bencf0706e82007-05-05 11:45:53 -070020#include "ieee80211_i.h"
21#include "michael.h"
22#include "tkip.h"
23#include "aes_ccm.h"
Jouni Malinen765cb462009-01-08 13:32:01 +020024#include "aes_cmac.h"
Jiri Bencf0706e82007-05-05 11:45:53 -070025#include "wpa.h"
26
Johannes Berg9ae54c82008-01-31 19:48:20 +010027ieee80211_tx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +010028ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
Jiri Bencf0706e82007-05-05 11:45:53 -070029{
Jouni Malinen747d7532011-02-03 18:34:28 +020030 u8 *data, *key, *mic;
Jiri Bencf0706e82007-05-05 11:45:53 -070031 size_t data_len;
Harvey Harrison8e8862b2008-07-02 11:05:35 -070032 unsigned int hdrlen;
33 struct ieee80211_hdr *hdr;
Jiri Bencf0706e82007-05-05 11:45:53 -070034 struct sk_buff *skb = tx->skb;
Johannes Berg813d7662010-01-17 01:47:58 +010035 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
Johannes Berg23c07522008-05-29 10:38:53 +020036 int tail;
Jiri Bencf0706e82007-05-05 11:45:53 -070037
Harvey Harrisonc34498b2008-07-02 16:30:52 -070038 hdr = (struct ieee80211_hdr *)skb->data;
Johannes Berg97359d12010-08-10 09:46:38 +020039 if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
40 skb->len < 24 || !ieee80211_is_data_present(hdr->frame_control))
Johannes Berg9ae54c82008-01-31 19:48:20 +010041 return TX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -070042
Harvey Harrison8e8862b2008-07-02 11:05:35 -070043 hdrlen = ieee80211_hdrlen(hdr->frame_control);
44 if (skb->len < hdrlen)
Johannes Berg9ae54c82008-01-31 19:48:20 +010045 return TX_DROP;
Jiri Bencf0706e82007-05-05 11:45:53 -070046
Harvey Harrison8e8862b2008-07-02 11:05:35 -070047 data = skb->data + hdrlen;
48 data_len = skb->len - hdrlen;
49
Jouni Malinen681d1192011-02-03 18:35:19 +020050 if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) {
51 /* Need to use software crypto for the test */
52 info->control.hw_key = NULL;
53 }
54
Johannes Berg813d7662010-01-17 01:47:58 +010055 if (info->control.hw_key &&
Johannes Berga26eb272011-10-07 14:01:25 +020056 (info->flags & IEEE80211_TX_CTL_DONTFRAG ||
57 tx->local->ops->set_frag_threshold) &&
Johannes Berg813d7662010-01-17 01:47:58 +010058 !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) {
59 /* hwaccel - with no need for SW-generated MMIC */
Johannes Berg9ae54c82008-01-31 19:48:20 +010060 return TX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -070061 }
62
Johannes Berg23c07522008-05-29 10:38:53 +020063 tail = MICHAEL_MIC_LEN;
Johannes Berg813d7662010-01-17 01:47:58 +010064 if (!info->control.hw_key)
Johannes Berg23c07522008-05-29 10:38:53 +020065 tail += TKIP_ICV_LEN;
66
67 if (WARN_ON(skb_tailroom(skb) < tail ||
68 skb_headroom(skb) < TKIP_IV_LEN))
69 return TX_DROP;
Jiri Bencf0706e82007-05-05 11:45:53 -070070
Jouni Malinen747d7532011-02-03 18:34:28 +020071 key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY];
Jiri Bencf0706e82007-05-05 11:45:53 -070072 mic = skb_put(skb, MICHAEL_MIC_LEN);
Harvey Harrison8e8862b2008-07-02 11:05:35 -070073 michael_mic(key, hdr, data, data_len, mic);
Jouni Malinen681d1192011-02-03 18:35:19 +020074 if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE))
75 mic[0]++;
Jiri Bencf0706e82007-05-05 11:45:53 -070076
Johannes Berg9ae54c82008-01-31 19:48:20 +010077 return TX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -070078}
79
80
Johannes Berg9ae54c82008-01-31 19:48:20 +010081ieee80211_rx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +010082ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
Jiri Bencf0706e82007-05-05 11:45:53 -070083{
Jouni Malinen747d7532011-02-03 18:34:28 +020084 u8 *data, *key = NULL;
Jiri Bencf0706e82007-05-05 11:45:53 -070085 size_t data_len;
Harvey Harrison8e8862b2008-07-02 11:05:35 -070086 unsigned int hdrlen;
Jiri Bencf0706e82007-05-05 11:45:53 -070087 u8 mic[MICHAEL_MIC_LEN];
88 struct sk_buff *skb = rx->skb;
Johannes Bergeb9fb5b2009-11-16 13:58:20 +010089 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
90 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
Jiri Bencf0706e82007-05-05 11:45:53 -070091
Christian Lamparter816c04f2011-04-30 15:24:30 +020092 /*
93 * it makes no sense to check for MIC errors on anything other
94 * than data frames.
95 */
96 if (!ieee80211_is_data_present(hdr->frame_control))
Johannes Berg9ae54c82008-01-31 19:48:20 +010097 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -070098
Christian Lamparter816c04f2011-04-30 15:24:30 +020099 /*
100 * No way to verify the MIC if the hardware stripped it or
101 * the IV with the key index. In this case we have solely rely
102 * on the driver to set RX_FLAG_MMIC_ERROR in the event of a
103 * MIC failure report.
104 */
105 if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) {
106 if (status->flag & RX_FLAG_MMIC_ERROR)
107 goto mic_fail;
108
Stanislaw Gruszka1140afa2012-01-11 09:26:54 +0100109 if (!(status->flag & RX_FLAG_IV_STRIPPED) && rx->key)
Christian Lamparter816c04f2011-04-30 15:24:30 +0200110 goto update_iv;
111
Johannes Berg9ae54c82008-01-31 19:48:20 +0100112 return RX_CONTINUE;
Christian Lamparter816c04f2011-04-30 15:24:30 +0200113 }
114
115 /*
116 * Some hardware seems to generate Michael MIC failure reports; even
117 * though, the frame was not encrypted with TKIP and therefore has no
118 * MIC. Ignore the flag them to avoid triggering countermeasures.
119 */
120 if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
121 !(status->flag & RX_FLAG_DECRYPTED))
122 return RX_CONTINUE;
123
124 if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) {
125 /*
126 * APs with pairwise keys should never receive Michael MIC
127 * errors for non-zero keyidx because these are reserved for
128 * group keys and only the AP is sending real multicast
129 * frames in the BSS. (
130 */
131 return RX_DROP_UNUSABLE;
132 }
133
134 if (status->flag & RX_FLAG_MMIC_ERROR)
135 goto mic_fail;
Jiri Bencf0706e82007-05-05 11:45:53 -0700136
Harvey Harrison8e8862b2008-07-02 11:05:35 -0700137 hdrlen = ieee80211_hdrlen(hdr->frame_control);
138 if (skb->len < hdrlen + MICHAEL_MIC_LEN)
Johannes Berge4c26ad2008-01-31 19:48:21 +0100139 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700140
Johannes Berga8286912012-03-12 13:49:14 +0100141 if (skb_linearize(rx->skb))
142 return RX_DROP_UNUSABLE;
143 hdr = (void *)skb->data;
144
Harvey Harrison8e8862b2008-07-02 11:05:35 -0700145 data = skb->data + hdrlen;
146 data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
Jouni Malinen747d7532011-02-03 18:34:28 +0200147 key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY];
Harvey Harrison8e8862b2008-07-02 11:05:35 -0700148 michael_mic(key, hdr, data, data_len, mic);
Christian Lamparter816c04f2011-04-30 15:24:30 +0200149 if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0)
150 goto mic_fail;
Jiri Bencf0706e82007-05-05 11:45:53 -0700151
Jiri Bencf0706e82007-05-05 11:45:53 -0700152 /* remove Michael MIC from payload */
153 skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
154
Christian Lamparter816c04f2011-04-30 15:24:30 +0200155update_iv:
Johannes Berg50741ae2007-09-26 15:19:45 +0200156 /* update IV in key information to be able to detect replays */
Johannes Berg9e262972011-07-07 18:45:03 +0200157 rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip_iv32;
158 rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip_iv16;
Johannes Berg50741ae2007-09-26 15:19:45 +0200159
Johannes Berg9ae54c82008-01-31 19:48:20 +0100160 return RX_CONTINUE;
Christian Lamparter816c04f2011-04-30 15:24:30 +0200161
162mic_fail:
Arik Nemtsova66b98d2011-06-23 00:00:24 +0300163 /*
164 * In some cases the key can be unset - e.g. a multicast packet, in
165 * a driver that supports HW encryption. Send up the key idx only if
166 * the key is set.
167 */
168 mac80211_ev_michael_mic_failure(rx->sdata,
169 rx->key ? rx->key->conf.keyidx : -1,
Christian Lamparter816c04f2011-04-30 15:24:30 +0200170 (void *) skb->data, NULL, GFP_ATOMIC);
171 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700172}
173
174
Johannes Berge039fa42008-05-15 12:55:29 +0200175static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
Jiri Bencf0706e82007-05-05 11:45:53 -0700176{
177 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
178 struct ieee80211_key *key = tx->key;
Johannes Berge039fa42008-05-15 12:55:29 +0200179 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
Johannes Berg523b02e2011-07-07 22:28:01 +0200180 unsigned long flags;
Harvey Harrisond5184ca2008-06-11 14:21:58 -0700181 unsigned int hdrlen;
182 int len, tail;
Jiri Bencf0706e82007-05-05 11:45:53 -0700183 u8 *pos;
184
Johannes Berg813d7662010-01-17 01:47:58 +0100185 if (info->control.hw_key &&
Janusz.Dziedzic@tieto.comee701082012-05-09 08:11:20 +0300186 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
187 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
Johannes Berg813d7662010-01-17 01:47:58 +0100188 /* hwaccel - with no need for software-generated IV */
Johannes Berg23c07522008-05-29 10:38:53 +0200189 return 0;
Johannes Berge039fa42008-05-15 12:55:29 +0200190 }
191
Harvey Harrisond5184ca2008-06-11 14:21:58 -0700192 hdrlen = ieee80211_hdrlen(hdr->frame_control);
Jiri Bencf0706e82007-05-05 11:45:53 -0700193 len = skb->len - hdrlen;
194
Johannes Berg813d7662010-01-17 01:47:58 +0100195 if (info->control.hw_key)
Johannes Berg23c07522008-05-29 10:38:53 +0200196 tail = 0;
Johannes Berg11a843b2007-08-28 17:01:55 -0400197 else
Johannes Berg23c07522008-05-29 10:38:53 +0200198 tail = TKIP_ICV_LEN;
Johannes Berg8f20fc22007-08-28 17:01:54 -0400199
Johannes Berg23c07522008-05-29 10:38:53 +0200200 if (WARN_ON(skb_tailroom(skb) < tail ||
201 skb_headroom(skb) < TKIP_IV_LEN))
202 return -1;
Jiri Bencf0706e82007-05-05 11:45:53 -0700203
204 pos = skb_push(skb, TKIP_IV_LEN);
205 memmove(pos, pos + TKIP_IV_LEN, hdrlen);
Arik Nemtsov78631572012-05-10 13:21:09 +0300206 skb_set_network_header(skb, skb_network_offset(skb) + TKIP_IV_LEN);
Jiri Bencf0706e82007-05-05 11:45:53 -0700207 pos += hdrlen;
208
Janusz.Dziedzic@tieto.comee701082012-05-09 08:11:20 +0300209 /* the HW only needs room for the IV, but not the actual IV */
210 if (info->control.hw_key &&
211 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
212 return 0;
213
Jiri Bencf0706e82007-05-05 11:45:53 -0700214 /* Increase IV for the frame */
Johannes Berg523b02e2011-07-07 22:28:01 +0200215 spin_lock_irqsave(&key->u.tkip.txlock, flags);
Harvey Harrisonb0f76b32008-05-14 16:26:19 -0700216 key->u.tkip.tx.iv16++;
217 if (key->u.tkip.tx.iv16 == 0)
218 key->u.tkip.tx.iv32++;
Johannes Berg523b02e2011-07-07 22:28:01 +0200219 pos = ieee80211_tkip_add_iv(pos, key);
220 spin_unlock_irqrestore(&key->u.tkip.txlock, flags);
Jiri Bencf0706e82007-05-05 11:45:53 -0700221
Johannes Berg813d7662010-01-17 01:47:58 +0100222 /* hwaccel - with software IV */
223 if (info->control.hw_key)
Jiri Bencf0706e82007-05-05 11:45:53 -0700224 return 0;
Jiri Bencf0706e82007-05-05 11:45:53 -0700225
226 /* Add room for ICV */
227 skb_put(skb, TKIP_ICV_LEN);
228
John W. Linville34731872010-07-07 15:07:49 -0400229 return ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
Johannes Berg523b02e2011-07-07 22:28:01 +0200230 key, skb, pos, len);
Jiri Bencf0706e82007-05-05 11:45:53 -0700231}
232
233
Johannes Berg9ae54c82008-01-31 19:48:20 +0100234ieee80211_tx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100235ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
Jiri Bencf0706e82007-05-05 11:45:53 -0700236{
Johannes Berg252b86c2011-11-16 15:28:55 +0100237 struct sk_buff *skb;
Jiri Bencf0706e82007-05-05 11:45:53 -0700238
Johannes Berg5cf121c2008-02-25 16:27:43 +0100239 ieee80211_tx_set_protected(tx);
Jiri Bencf0706e82007-05-05 11:45:53 -0700240
Johannes Berg252b86c2011-11-16 15:28:55 +0100241 skb_queue_walk(&tx->skbs, skb) {
Johannes Berg2de8e0d2009-03-23 17:28:35 +0100242 if (tkip_encrypt_skb(tx, skb) < 0)
243 return TX_DROP;
Johannes Berg252b86c2011-11-16 15:28:55 +0100244 }
Jiri Bencf0706e82007-05-05 11:45:53 -0700245
Johannes Berg9ae54c82008-01-31 19:48:20 +0100246 return TX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700247}
248
249
Johannes Berg9ae54c82008-01-31 19:48:20 +0100250ieee80211_rx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100251ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
Jiri Bencf0706e82007-05-05 11:45:53 -0700252{
253 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
Jouni Malinen747d7532011-02-03 18:34:28 +0200254 int hdrlen, res, hwaccel = 0;
Jiri Bencf0706e82007-05-05 11:45:53 -0700255 struct ieee80211_key *key = rx->key;
256 struct sk_buff *skb = rx->skb;
Johannes Bergeb9fb5b2009-11-16 13:58:20 +0100257 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
Jiri Bencf0706e82007-05-05 11:45:53 -0700258
Harvey Harrisond5184ca2008-06-11 14:21:58 -0700259 hdrlen = ieee80211_hdrlen(hdr->frame_control);
Jiri Bencf0706e82007-05-05 11:45:53 -0700260
Harvey Harrisonc34498b2008-07-02 16:30:52 -0700261 if (!ieee80211_is_data(hdr->frame_control))
Johannes Berg9ae54c82008-01-31 19:48:20 +0100262 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700263
264 if (!rx->sta || skb->len - hdrlen < 12)
Johannes Berge4c26ad2008-01-31 19:48:21 +0100265 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700266
Johannes Berga8286912012-03-12 13:49:14 +0100267 /* it may be possible to optimize this a bit more */
268 if (skb_linearize(rx->skb))
269 return RX_DROP_UNUSABLE;
270 hdr = (void *)skb->data;
271
Johannes Bergdc1580d2010-08-10 09:46:40 +0200272 /*
273 * Let TKIP code verify IV, but skip decryption.
274 * In the case where hardware checks the IV as well,
275 * we don't even get here, see ieee80211_rx_h_decrypt()
276 */
277 if (status->flag & RX_FLAG_DECRYPTED)
Jiri Bencf0706e82007-05-05 11:45:53 -0700278 hwaccel = 1;
Jiri Bencf0706e82007-05-05 11:45:53 -0700279
280 res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,
281 key, skb->data + hdrlen,
Johannes Berg17741cd2008-09-11 00:02:02 +0200282 skb->len - hdrlen, rx->sta->sta.addr,
Johannes Berg9e262972011-07-07 18:45:03 +0200283 hdr->addr1, hwaccel, rx->security_idx,
Johannes Berg5cf121c2008-02-25 16:27:43 +0100284 &rx->tkip_iv32,
285 &rx->tkip_iv16);
Jouni Malinen747d7532011-02-03 18:34:28 +0200286 if (res != TKIP_DECRYPT_OK)
Johannes Berge4c26ad2008-01-31 19:48:21 +0100287 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700288
289 /* Trim ICV */
290 skb_trim(skb, skb->len - TKIP_ICV_LEN);
291
292 /* Remove IV */
293 memmove(skb->data + TKIP_IV_LEN, skb->data, hdrlen);
294 skb_pull(skb, TKIP_IV_LEN);
295
Johannes Berg9ae54c82008-01-31 19:48:20 +0100296 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700297}
298
299
Harvey Harrisonfeccb462008-07-02 16:30:52 -0700300static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *scratch,
Jiri Bencf0706e82007-05-05 11:45:53 -0700301 int encrypted)
302{
Harvey Harrisonf14df802008-07-02 11:05:35 -0700303 __le16 mask_fc;
Jouni Malinenfb733332009-01-08 13:32:00 +0200304 int a4_included, mgmt;
Harvey Harrisonf14df802008-07-02 11:05:35 -0700305 u8 qos_tid;
Harvey Harrisonfeccb462008-07-02 16:30:52 -0700306 u8 *b_0, *aad;
Harvey Harrisonf14df802008-07-02 11:05:35 -0700307 u16 data_len, len_a;
308 unsigned int hdrlen;
309 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
Jiri Bencf0706e82007-05-05 11:45:53 -0700310
Johannes Berg0cd20a22011-07-06 22:02:14 +0200311 memset(scratch, 0, 6 * AES_BLOCK_SIZE);
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200312
Johannes Berg0cd20a22011-07-06 22:02:14 +0200313 b_0 = scratch + 3 * AES_BLOCK_SIZE;
314 aad = scratch + 4 * AES_BLOCK_SIZE;
Harvey Harrisonfeccb462008-07-02 16:30:52 -0700315
Harvey Harrisonf14df802008-07-02 11:05:35 -0700316 /*
Jouni Malinenfb733332009-01-08 13:32:00 +0200317 * Mask FC: zero subtype b4 b5 b6 (if not mgmt)
Harvey Harrisonf14df802008-07-02 11:05:35 -0700318 * Retry, PwrMgt, MoreData; set Protected
319 */
Jouni Malinenfb733332009-01-08 13:32:00 +0200320 mgmt = ieee80211_is_mgmt(hdr->frame_control);
Harvey Harrisonf14df802008-07-02 11:05:35 -0700321 mask_fc = hdr->frame_control;
Jouni Malinenfb733332009-01-08 13:32:00 +0200322 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
Harvey Harrisonf14df802008-07-02 11:05:35 -0700323 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
Jouni Malinenfb733332009-01-08 13:32:00 +0200324 if (!mgmt)
325 mask_fc &= ~cpu_to_le16(0x0070);
Harvey Harrisonf14df802008-07-02 11:05:35 -0700326 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
Jiri Bencf0706e82007-05-05 11:45:53 -0700327
Harvey Harrisonf14df802008-07-02 11:05:35 -0700328 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 data_len = skb->len - hdrlen - CCMP_HDR_LEN;
338 if (encrypted)
339 data_len -= CCMP_MIC_LEN;
340
Jiri Bencf0706e82007-05-05 11:45:53 -0700341 /* First block, b_0 */
Jiri Bencf0706e82007-05-05 11:45:53 -0700342 b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */
Jouni Malinenfb733332009-01-08 13:32:00 +0200343 /* Nonce: Nonce Flags | A2 | PN
344 * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7)
345 */
346 b_0[1] = qos_tid | (mgmt << 4);
Harvey Harrison73e1f7c2008-07-02 11:05:34 -0700347 memcpy(&b_0[2], hdr->addr2, ETH_ALEN);
Jiri Bencf0706e82007-05-05 11:45:53 -0700348 memcpy(&b_0[8], pn, CCMP_PN_LEN);
349 /* l(m) */
Harvey Harrisonf14df802008-07-02 11:05:35 -0700350 put_unaligned_be16(data_len, &b_0[14]);
Jiri Bencf0706e82007-05-05 11:45:53 -0700351
352 /* AAD (extra authenticate-only data) / masked 802.11 header
353 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */
Harvey Harrisonf14df802008-07-02 11:05:35 -0700354 put_unaligned_be16(len_a, &aad[0]);
355 put_unaligned(mask_fc, (__le16 *)&aad[2]);
Harvey Harrison73e1f7c2008-07-02 11:05:34 -0700356 memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
Jiri Bencf0706e82007-05-05 11:45:53 -0700357
358 /* Mask Seq#, leave Frag# */
359 aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
360 aad[23] = 0;
Harvey Harrisonf14df802008-07-02 11:05:35 -0700361
Jiri Bencf0706e82007-05-05 11:45:53 -0700362 if (a4_included) {
Harvey Harrison73e1f7c2008-07-02 11:05:34 -0700363 memcpy(&aad[24], hdr->addr4, ETH_ALEN);
Harvey Harrisonf14df802008-07-02 11:05:35 -0700364 aad[30] = qos_tid;
Jiri Bencf0706e82007-05-05 11:45:53 -0700365 aad[31] = 0;
Harvey Harrisonf14df802008-07-02 11:05:35 -0700366 } else {
Harvey Harrison73e1f7c2008-07-02 11:05:34 -0700367 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
Harvey Harrisonf14df802008-07-02 11:05:35 -0700368 aad[24] = qos_tid;
Jiri Bencf0706e82007-05-05 11:45:53 -0700369 }
370}
371
372
373static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
374{
375 hdr[0] = pn[5];
376 hdr[1] = pn[4];
377 hdr[2] = 0;
378 hdr[3] = 0x20 | (key_id << 6);
379 hdr[4] = pn[3];
380 hdr[5] = pn[2];
381 hdr[6] = pn[1];
382 hdr[7] = pn[0];
383}
384
385
Johannes Bergc6a1fa12008-10-07 12:04:32 +0200386static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr)
Jiri Bencf0706e82007-05-05 11:45:53 -0700387{
388 pn[0] = hdr[7];
389 pn[1] = hdr[6];
390 pn[2] = hdr[5];
391 pn[3] = hdr[4];
392 pn[4] = hdr[1];
393 pn[5] = hdr[0];
Jiri Bencf0706e82007-05-05 11:45:53 -0700394}
395
396
Johannes Berge039fa42008-05-15 12:55:29 +0200397static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
Jiri Bencf0706e82007-05-05 11:45:53 -0700398{
399 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
400 struct ieee80211_key *key = tx->key;
Johannes Berge039fa42008-05-15 12:55:29 +0200401 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
Johannes Berg23c07522008-05-29 10:38:53 +0200402 int hdrlen, len, tail;
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200403 u8 *pos;
404 u8 pn[6];
405 u64 pn64;
Johannes Berg0cd20a22011-07-06 22:02:14 +0200406 u8 scratch[6 * AES_BLOCK_SIZE];
Jouni Malinen1f7d77a2009-01-08 13:32:10 +0200407
Johannes Berg813d7662010-01-17 01:47:58 +0100408 if (info->control.hw_key &&
Arik Nemtsov077a9152011-10-23 08:21:41 +0200409 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
410 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
Johannes Berg813d7662010-01-17 01:47:58 +0100411 /*
412 * hwaccel has no need for preallocated room for CCMP
413 * header or MIC fields
414 */
Johannes Berg23c07522008-05-29 10:38:53 +0200415 return 0;
Johannes Berge039fa42008-05-15 12:55:29 +0200416 }
417
Harvey Harrisond5184ca2008-06-11 14:21:58 -0700418 hdrlen = ieee80211_hdrlen(hdr->frame_control);
Jiri Bencf0706e82007-05-05 11:45:53 -0700419 len = skb->len - hdrlen;
420
Johannes Berg813d7662010-01-17 01:47:58 +0100421 if (info->control.hw_key)
Johannes Berg23c07522008-05-29 10:38:53 +0200422 tail = 0;
Johannes Berg11a843b2007-08-28 17:01:55 -0400423 else
Johannes Berg23c07522008-05-29 10:38:53 +0200424 tail = CCMP_MIC_LEN;
Jiri Bencf0706e82007-05-05 11:45:53 -0700425
Johannes Berg23c07522008-05-29 10:38:53 +0200426 if (WARN_ON(skb_tailroom(skb) < tail ||
427 skb_headroom(skb) < CCMP_HDR_LEN))
428 return -1;
Jiri Bencf0706e82007-05-05 11:45:53 -0700429
430 pos = skb_push(skb, CCMP_HDR_LEN);
431 memmove(pos, pos + CCMP_HDR_LEN, hdrlen);
Arik Nemtsov78631572012-05-10 13:21:09 +0300432 skb_set_network_header(skb, skb_network_offset(skb) + CCMP_HDR_LEN);
Arik Nemtsov077a9152011-10-23 08:21:41 +0200433
434 /* the HW only needs room for the IV, but not the actual IV */
Arik Nemtsove0830f72011-11-10 09:35:13 +0200435 if (info->control.hw_key &&
436 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
Arik Nemtsov077a9152011-10-23 08:21:41 +0200437 return 0;
438
Jiri Bencf0706e82007-05-05 11:45:53 -0700439 hdr = (struct ieee80211_hdr *) pos;
440 pos += hdrlen;
441
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200442 pn64 = atomic64_inc_return(&key->u.ccmp.tx_pn);
Jiri Bencf0706e82007-05-05 11:45:53 -0700443
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200444 pn[5] = pn64;
445 pn[4] = pn64 >> 8;
446 pn[3] = pn64 >> 16;
447 pn[2] = pn64 >> 24;
448 pn[1] = pn64 >> 32;
449 pn[0] = pn64 >> 40;
Jiri Bencf0706e82007-05-05 11:45:53 -0700450
Johannes Berg8f20fc22007-08-28 17:01:54 -0400451 ccmp_pn2hdr(pos, pn, key->conf.keyidx);
Jiri Bencf0706e82007-05-05 11:45:53 -0700452
Johannes Berg813d7662010-01-17 01:47:58 +0100453 /* hwaccel - with software CCMP header */
454 if (info->control.hw_key)
Jiri Bencf0706e82007-05-05 11:45:53 -0700455 return 0;
Jiri Bencf0706e82007-05-05 11:45:53 -0700456
457 pos += CCMP_HDR_LEN;
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200458 ccmp_special_blocks(skb, pn, scratch, 0);
459 ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, scratch, pos, len,
Jiri Bencf0706e82007-05-05 11:45:53 -0700460 pos, skb_put(skb, CCMP_MIC_LEN));
461
462 return 0;
463}
464
465
Johannes Berg9ae54c82008-01-31 19:48:20 +0100466ieee80211_tx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100467ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx)
Jiri Bencf0706e82007-05-05 11:45:53 -0700468{
Johannes Berg252b86c2011-11-16 15:28:55 +0100469 struct sk_buff *skb;
Jiri Bencf0706e82007-05-05 11:45:53 -0700470
Johannes Berg5cf121c2008-02-25 16:27:43 +0100471 ieee80211_tx_set_protected(tx);
Jiri Bencf0706e82007-05-05 11:45:53 -0700472
Johannes Berg252b86c2011-11-16 15:28:55 +0100473 skb_queue_walk(&tx->skbs, skb) {
Johannes Berg2de8e0d2009-03-23 17:28:35 +0100474 if (ccmp_encrypt_skb(tx, skb) < 0)
475 return TX_DROP;
Johannes Berg252b86c2011-11-16 15:28:55 +0100476 }
Jiri Bencf0706e82007-05-05 11:45:53 -0700477
Johannes Berg9ae54c82008-01-31 19:48:20 +0100478 return TX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700479}
480
481
Johannes Berg9ae54c82008-01-31 19:48:20 +0100482ieee80211_rx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100483ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx)
Jiri Bencf0706e82007-05-05 11:45:53 -0700484{
Harvey Harrisonc34498b2008-07-02 16:30:52 -0700485 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
Jiri Bencf0706e82007-05-05 11:45:53 -0700486 int hdrlen;
487 struct ieee80211_key *key = rx->key;
488 struct sk_buff *skb = rx->skb;
Johannes Bergeb9fb5b2009-11-16 13:58:20 +0100489 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
Jiri Bencf0706e82007-05-05 11:45:53 -0700490 u8 pn[CCMP_PN_LEN];
491 int data_len;
Jouni Malinen91902522010-06-11 10:27:33 -0700492 int queue;
Jiri Bencf0706e82007-05-05 11:45:53 -0700493
Harvey Harrisond5184ca2008-06-11 14:21:58 -0700494 hdrlen = ieee80211_hdrlen(hdr->frame_control);
Jiri Bencf0706e82007-05-05 11:45:53 -0700495
Jouni Malinenfb733332009-01-08 13:32:00 +0200496 if (!ieee80211_is_data(hdr->frame_control) &&
497 !ieee80211_is_robust_mgmt_frame(hdr))
Johannes Berg9ae54c82008-01-31 19:48:20 +0100498 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700499
500 data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN;
501 if (!rx->sta || data_len < 0)
Johannes Berge4c26ad2008-01-31 19:48:21 +0100502 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700503
Johannes Berga8286912012-03-12 13:49:14 +0100504 if (status->flag & RX_FLAG_DECRYPTED) {
505 if (!pskb_may_pull(rx->skb, hdrlen + CCMP_HDR_LEN))
506 return RX_DROP_UNUSABLE;
507 } else {
508 if (skb_linearize(rx->skb))
509 return RX_DROP_UNUSABLE;
510 }
511
Johannes Bergc6a1fa12008-10-07 12:04:32 +0200512 ccmp_hdr2pn(pn, skb->data + hdrlen);
Jiri Bencf0706e82007-05-05 11:45:53 -0700513
Johannes Berg9e262972011-07-07 18:45:03 +0200514 queue = rx->security_idx;
Jouni Malinen91902522010-06-11 10:27:33 -0700515
516 if (memcmp(pn, key->u.ccmp.rx_pn[queue], CCMP_PN_LEN) <= 0) {
Jiri Bencf0706e82007-05-05 11:45:53 -0700517 key->u.ccmp.replays++;
Johannes Berge4c26ad2008-01-31 19:48:21 +0100518 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700519 }
520
Johannes Bergeb9fb5b2009-11-16 13:58:20 +0100521 if (!(status->flag & RX_FLAG_DECRYPTED)) {
Johannes Berg0cd20a22011-07-06 22:02:14 +0200522 u8 scratch[6 * AES_BLOCK_SIZE];
Johannes Berg7848ba72007-09-14 11:10:25 -0400523 /* hardware didn't decrypt/verify MIC */
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200524 ccmp_special_blocks(skb, pn, scratch, 1);
Jiri Bencf0706e82007-05-05 11:45:53 -0700525
526 if (ieee80211_aes_ccm_decrypt(
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200527 key->u.ccmp.tfm, scratch,
Jiri Bencf0706e82007-05-05 11:45:53 -0700528 skb->data + hdrlen + CCMP_HDR_LEN, data_len,
529 skb->data + skb->len - CCMP_MIC_LEN,
Johannes Bergc6a1fa12008-10-07 12:04:32 +0200530 skb->data + hdrlen + CCMP_HDR_LEN))
Johannes Berge4c26ad2008-01-31 19:48:21 +0100531 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700532 }
533
Jouni Malinen91902522010-06-11 10:27:33 -0700534 memcpy(key->u.ccmp.rx_pn[queue], pn, CCMP_PN_LEN);
Jiri Bencf0706e82007-05-05 11:45:53 -0700535
536 /* Remove CCMP header and MIC */
Johannes Berga8286912012-03-12 13:49:14 +0100537 if (pskb_trim(skb, skb->len - CCMP_MIC_LEN))
538 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700539 memmove(skb->data + CCMP_HDR_LEN, skb->data, hdrlen);
540 skb_pull(skb, CCMP_HDR_LEN);
541
Johannes Berg9ae54c82008-01-31 19:48:20 +0100542 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700543}
Jouni Malinen765cb462009-01-08 13:32:01 +0200544
545
546static void bip_aad(struct sk_buff *skb, u8 *aad)
547{
548 /* BIP AAD: FC(masked) || A1 || A2 || A3 */
549
550 /* FC type/subtype */
551 aad[0] = skb->data[0];
552 /* Mask FC Retry, PwrMgt, MoreData flags to zero */
553 aad[1] = skb->data[1] & ~(BIT(4) | BIT(5) | BIT(6));
554 /* A1 || A2 || A3 */
555 memcpy(aad + 2, skb->data + 4, 3 * ETH_ALEN);
556}
557
558
Johannes Berg75396ae2011-07-06 22:00:35 +0200559static inline void bip_ipn_set64(u8 *d, u64 pn)
560{
561 *d++ = pn;
562 *d++ = pn >> 8;
563 *d++ = pn >> 16;
564 *d++ = pn >> 24;
565 *d++ = pn >> 32;
566 *d = pn >> 40;
567}
568
Jouni Malinen765cb462009-01-08 13:32:01 +0200569static inline void bip_ipn_swap(u8 *d, const u8 *s)
570{
571 *d++ = s[5];
572 *d++ = s[4];
573 *d++ = s[3];
574 *d++ = s[2];
575 *d++ = s[1];
576 *d = s[0];
577}
578
579
580ieee80211_tx_result
581ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
582{
Johannes Berg252b86c2011-11-16 15:28:55 +0100583 struct sk_buff *skb;
584 struct ieee80211_tx_info *info;
Jouni Malinen765cb462009-01-08 13:32:01 +0200585 struct ieee80211_key *key = tx->key;
586 struct ieee80211_mmie *mmie;
Johannes Berg75396ae2011-07-06 22:00:35 +0200587 u8 aad[20];
588 u64 pn64;
Jouni Malinen765cb462009-01-08 13:32:01 +0200589
Johannes Berg252b86c2011-11-16 15:28:55 +0100590 if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
591 return TX_DROP;
592
593 skb = skb_peek(&tx->skbs);
594
595 info = IEEE80211_SKB_CB(skb);
596
Johannes Berg813d7662010-01-17 01:47:58 +0100597 if (info->control.hw_key)
Johannes Berg252b86c2011-11-16 15:28:55 +0100598 return TX_CONTINUE;
Jouni Malinen765cb462009-01-08 13:32:01 +0200599
600 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
601 return TX_DROP;
602
603 mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie));
604 mmie->element_id = WLAN_EID_MMIE;
605 mmie->length = sizeof(*mmie) - 2;
606 mmie->key_id = cpu_to_le16(key->conf.keyidx);
607
608 /* PN = PN + 1 */
Johannes Berg75396ae2011-07-06 22:00:35 +0200609 pn64 = atomic64_inc_return(&key->u.aes_cmac.tx_pn);
Jouni Malinen765cb462009-01-08 13:32:01 +0200610
Johannes Berg75396ae2011-07-06 22:00:35 +0200611 bip_ipn_set64(mmie->sequence_number, pn64);
Jouni Malinen765cb462009-01-08 13:32:01 +0200612
613 bip_aad(skb, aad);
614
615 /*
616 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
617 */
Johannes Berg75396ae2011-07-06 22:00:35 +0200618 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
619 skb->data + 24, skb->len - 24, mmie->mic);
Jouni Malinen765cb462009-01-08 13:32:01 +0200620
621 return TX_CONTINUE;
622}
623
624
625ieee80211_rx_result
626ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
627{
628 struct sk_buff *skb = rx->skb;
Johannes Bergeb9fb5b2009-11-16 13:58:20 +0100629 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
Jouni Malinen765cb462009-01-08 13:32:01 +0200630 struct ieee80211_key *key = rx->key;
631 struct ieee80211_mmie *mmie;
632 u8 aad[20], mic[8], ipn[6];
633 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
634
635 if (!ieee80211_is_mgmt(hdr->frame_control))
636 return RX_CONTINUE;
637
Johannes Berga8286912012-03-12 13:49:14 +0100638 /* management frames are already linear */
639
Jouni Malinen765cb462009-01-08 13:32:01 +0200640 if (skb->len < 24 + sizeof(*mmie))
641 return RX_DROP_UNUSABLE;
642
643 mmie = (struct ieee80211_mmie *)
644 (skb->data + skb->len - sizeof(*mmie));
645 if (mmie->element_id != WLAN_EID_MMIE ||
646 mmie->length != sizeof(*mmie) - 2)
647 return RX_DROP_UNUSABLE; /* Invalid MMIE */
648
649 bip_ipn_swap(ipn, mmie->sequence_number);
650
651 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
652 key->u.aes_cmac.replays++;
653 return RX_DROP_UNUSABLE;
654 }
655
Johannes Bergeb9fb5b2009-11-16 13:58:20 +0100656 if (!(status->flag & RX_FLAG_DECRYPTED)) {
Jouni Malinen765cb462009-01-08 13:32:01 +0200657 /* hardware didn't decrypt/verify MIC */
658 bip_aad(skb, aad);
Johannes Berg75396ae2011-07-06 22:00:35 +0200659 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
Jouni Malinen765cb462009-01-08 13:32:01 +0200660 skb->data + 24, skb->len - 24, mic);
661 if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
662 key->u.aes_cmac.icverrors++;
663 return RX_DROP_UNUSABLE;
664 }
665 }
666
667 memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
668
669 /* Remove MMIE */
670 skb_trim(skb, skb->len - sizeof(*mmie));
671
672 return RX_CONTINUE;
673}
Yoni Divinskyd32a1022012-01-16 15:18:59 +0200674
675ieee80211_tx_result
676ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx)
677{
678 struct sk_buff *skb;
679 struct ieee80211_tx_info *info = NULL;
680
681 skb_queue_walk(&tx->skbs, skb) {
682 info = IEEE80211_SKB_CB(skb);
683
684 /* handle hw-only algorithm */
685 if (!info->control.hw_key)
686 return TX_DROP;
687 }
688
689 ieee80211_tx_set_protected(tx);
690
691 return TX_CONTINUE;
692}