blob: 0ae23c60968c0a9e82b214042ee5b01c4f27bb7d [file] [log] [blame]
Jiri Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 11:45:53 -070029{
Jouni Malinen747d7532011-02-03 18:34:28 +020030 u8 *data, *key, *mic;
Jiri Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 11:45:53 -070076
Johannes Berg9ae54c82008-01-31 19:48:20 +010077 return TX_CONTINUE;
Jiri Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 11:45:53 -070083{
Jouni Malinen747d7532011-02-03 18:34:28 +020084 u8 *data, *key = NULL;
Jiri Bencf0706e822007-05-05 11:45:53 -070085 size_t data_len;
Harvey Harrison8e8862b2008-07-02 11:05:35 -070086 unsigned int hdrlen;
Jiri Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 11:45:53 -0700151
Jiri Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 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 Bencf0706e822007-05-05 11:45:53 -0700183 u8 *pos;
184
Johannes Berg813d7662010-01-17 01:47:58 +0100185 if (info->control.hw_key &&
186 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV)) {
187 /* hwaccel - with no need for software-generated IV */
Johannes Berg23c07522008-05-29 10:38:53 +0200188 return 0;
Johannes Berge039fa42008-05-15 12:55:29 +0200189 }
190
Harvey Harrisond5184ca2008-06-11 14:21:58 -0700191 hdrlen = ieee80211_hdrlen(hdr->frame_control);
Jiri Bencf0706e822007-05-05 11:45:53 -0700192 len = skb->len - hdrlen;
193
Johannes Berg813d7662010-01-17 01:47:58 +0100194 if (info->control.hw_key)
Johannes Berg23c07522008-05-29 10:38:53 +0200195 tail = 0;
Johannes Berg11a843b2007-08-28 17:01:55 -0400196 else
Johannes Berg23c07522008-05-29 10:38:53 +0200197 tail = TKIP_ICV_LEN;
Johannes Berg8f20fc22007-08-28 17:01:54 -0400198
Johannes Berg23c07522008-05-29 10:38:53 +0200199 if (WARN_ON(skb_tailroom(skb) < tail ||
200 skb_headroom(skb) < TKIP_IV_LEN))
201 return -1;
Jiri Bencf0706e822007-05-05 11:45:53 -0700202
203 pos = skb_push(skb, TKIP_IV_LEN);
204 memmove(pos, pos + TKIP_IV_LEN, hdrlen);
205 pos += hdrlen;
206
207 /* Increase IV for the frame */
Johannes Berg523b02e2011-07-07 22:28:01 +0200208 spin_lock_irqsave(&key->u.tkip.txlock, flags);
Harvey Harrisonb0f76b32008-05-14 16:26:19 -0700209 key->u.tkip.tx.iv16++;
210 if (key->u.tkip.tx.iv16 == 0)
211 key->u.tkip.tx.iv32++;
Johannes Berg523b02e2011-07-07 22:28:01 +0200212 pos = ieee80211_tkip_add_iv(pos, key);
213 spin_unlock_irqrestore(&key->u.tkip.txlock, flags);
Jiri Bencf0706e822007-05-05 11:45:53 -0700214
Johannes Berg813d7662010-01-17 01:47:58 +0100215 /* hwaccel - with software IV */
216 if (info->control.hw_key)
Jiri Bencf0706e822007-05-05 11:45:53 -0700217 return 0;
Jiri Bencf0706e822007-05-05 11:45:53 -0700218
219 /* Add room for ICV */
220 skb_put(skb, TKIP_ICV_LEN);
221
John W. Linville34731872010-07-07 15:07:49 -0400222 return ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
Johannes Berg523b02e2011-07-07 22:28:01 +0200223 key, skb, pos, len);
Jiri Bencf0706e822007-05-05 11:45:53 -0700224}
225
226
Johannes Berg9ae54c82008-01-31 19:48:20 +0100227ieee80211_tx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100228ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
Jiri Bencf0706e822007-05-05 11:45:53 -0700229{
Johannes Berg252b86c2011-11-16 15:28:55 +0100230 struct sk_buff *skb;
Jiri Bencf0706e822007-05-05 11:45:53 -0700231
Johannes Berg5cf121c2008-02-25 16:27:43 +0100232 ieee80211_tx_set_protected(tx);
Jiri Bencf0706e822007-05-05 11:45:53 -0700233
Johannes Berg252b86c2011-11-16 15:28:55 +0100234 skb_queue_walk(&tx->skbs, skb) {
Johannes Berg2de8e0d2009-03-23 17:28:35 +0100235 if (tkip_encrypt_skb(tx, skb) < 0)
236 return TX_DROP;
Johannes Berg252b86c2011-11-16 15:28:55 +0100237 }
Jiri Bencf0706e822007-05-05 11:45:53 -0700238
Johannes Berg9ae54c82008-01-31 19:48:20 +0100239 return TX_CONTINUE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700240}
241
242
Johannes Berg9ae54c82008-01-31 19:48:20 +0100243ieee80211_rx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100244ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
Jiri Bencf0706e822007-05-05 11:45:53 -0700245{
246 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
Jouni Malinen747d7532011-02-03 18:34:28 +0200247 int hdrlen, res, hwaccel = 0;
Jiri Bencf0706e822007-05-05 11:45:53 -0700248 struct ieee80211_key *key = rx->key;
249 struct sk_buff *skb = rx->skb;
Johannes Bergeb9fb5b2009-11-16 13:58:20 +0100250 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
Jiri Bencf0706e822007-05-05 11:45:53 -0700251
Harvey Harrisond5184ca2008-06-11 14:21:58 -0700252 hdrlen = ieee80211_hdrlen(hdr->frame_control);
Jiri Bencf0706e822007-05-05 11:45:53 -0700253
Harvey Harrisonc34498b2008-07-02 16:30:52 -0700254 if (!ieee80211_is_data(hdr->frame_control))
Johannes Berg9ae54c82008-01-31 19:48:20 +0100255 return RX_CONTINUE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700256
257 if (!rx->sta || skb->len - hdrlen < 12)
Johannes Berge4c26ad2008-01-31 19:48:21 +0100258 return RX_DROP_UNUSABLE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700259
Johannes Berga8286912012-03-12 13:49:14 +0100260 /* it may be possible to optimize this a bit more */
261 if (skb_linearize(rx->skb))
262 return RX_DROP_UNUSABLE;
263 hdr = (void *)skb->data;
264
Johannes Bergdc1580d2010-08-10 09:46:40 +0200265 /*
266 * Let TKIP code verify IV, but skip decryption.
267 * In the case where hardware checks the IV as well,
268 * we don't even get here, see ieee80211_rx_h_decrypt()
269 */
270 if (status->flag & RX_FLAG_DECRYPTED)
Jiri Bencf0706e822007-05-05 11:45:53 -0700271 hwaccel = 1;
Jiri Bencf0706e822007-05-05 11:45:53 -0700272
273 res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,
274 key, skb->data + hdrlen,
Johannes Berg17741cd2008-09-11 00:02:02 +0200275 skb->len - hdrlen, rx->sta->sta.addr,
Johannes Berg9e262972011-07-07 18:45:03 +0200276 hdr->addr1, hwaccel, rx->security_idx,
Johannes Berg5cf121c2008-02-25 16:27:43 +0100277 &rx->tkip_iv32,
278 &rx->tkip_iv16);
Jouni Malinen747d7532011-02-03 18:34:28 +0200279 if (res != TKIP_DECRYPT_OK)
Johannes Berge4c26ad2008-01-31 19:48:21 +0100280 return RX_DROP_UNUSABLE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700281
282 /* Trim ICV */
283 skb_trim(skb, skb->len - TKIP_ICV_LEN);
284
285 /* Remove IV */
286 memmove(skb->data + TKIP_IV_LEN, skb->data, hdrlen);
287 skb_pull(skb, TKIP_IV_LEN);
288
Johannes Berg9ae54c82008-01-31 19:48:20 +0100289 return RX_CONTINUE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700290}
291
292
Harvey Harrisonfeccb462008-07-02 16:30:52 -0700293static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *scratch,
Jiri Bencf0706e822007-05-05 11:45:53 -0700294 int encrypted)
295{
Harvey Harrisonf14df802008-07-02 11:05:35 -0700296 __le16 mask_fc;
Jouni Malinenfb733332009-01-08 13:32:00 +0200297 int a4_included, mgmt;
Harvey Harrisonf14df802008-07-02 11:05:35 -0700298 u8 qos_tid;
Harvey Harrisonfeccb462008-07-02 16:30:52 -0700299 u8 *b_0, *aad;
Harvey Harrisonf14df802008-07-02 11:05:35 -0700300 u16 data_len, len_a;
301 unsigned int hdrlen;
302 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
Jiri Bencf0706e822007-05-05 11:45:53 -0700303
Johannes Berg0cd20a22011-07-06 22:02:14 +0200304 memset(scratch, 0, 6 * AES_BLOCK_SIZE);
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200305
Johannes Berg0cd20a22011-07-06 22:02:14 +0200306 b_0 = scratch + 3 * AES_BLOCK_SIZE;
307 aad = scratch + 4 * AES_BLOCK_SIZE;
Harvey Harrisonfeccb462008-07-02 16:30:52 -0700308
Harvey Harrisonf14df802008-07-02 11:05:35 -0700309 /*
Jouni Malinenfb733332009-01-08 13:32:00 +0200310 * Mask FC: zero subtype b4 b5 b6 (if not mgmt)
Harvey Harrisonf14df802008-07-02 11:05:35 -0700311 * Retry, PwrMgt, MoreData; set Protected
312 */
Jouni Malinenfb733332009-01-08 13:32:00 +0200313 mgmt = ieee80211_is_mgmt(hdr->frame_control);
Harvey Harrisonf14df802008-07-02 11:05:35 -0700314 mask_fc = hdr->frame_control;
Jouni Malinenfb733332009-01-08 13:32:00 +0200315 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
Harvey Harrisonf14df802008-07-02 11:05:35 -0700316 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
Jouni Malinenfb733332009-01-08 13:32:00 +0200317 if (!mgmt)
318 mask_fc &= ~cpu_to_le16(0x0070);
Harvey Harrisonf14df802008-07-02 11:05:35 -0700319 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
Jiri Bencf0706e822007-05-05 11:45:53 -0700320
Harvey Harrisonf14df802008-07-02 11:05:35 -0700321 hdrlen = ieee80211_hdrlen(hdr->frame_control);
322 len_a = hdrlen - 2;
323 a4_included = ieee80211_has_a4(hdr->frame_control);
324
325 if (ieee80211_is_data_qos(hdr->frame_control))
326 qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
327 else
328 qos_tid = 0;
329
330 data_len = skb->len - hdrlen - CCMP_HDR_LEN;
331 if (encrypted)
332 data_len -= CCMP_MIC_LEN;
333
Jiri Bencf0706e822007-05-05 11:45:53 -0700334 /* First block, b_0 */
Jiri Bencf0706e822007-05-05 11:45:53 -0700335 b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */
Jouni Malinenfb733332009-01-08 13:32:00 +0200336 /* Nonce: Nonce Flags | A2 | PN
337 * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7)
338 */
339 b_0[1] = qos_tid | (mgmt << 4);
Harvey Harrison73e1f7c2008-07-02 11:05:34 -0700340 memcpy(&b_0[2], hdr->addr2, ETH_ALEN);
Jiri Bencf0706e822007-05-05 11:45:53 -0700341 memcpy(&b_0[8], pn, CCMP_PN_LEN);
342 /* l(m) */
Harvey Harrisonf14df802008-07-02 11:05:35 -0700343 put_unaligned_be16(data_len, &b_0[14]);
Jiri Bencf0706e822007-05-05 11:45:53 -0700344
345 /* AAD (extra authenticate-only data) / masked 802.11 header
346 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */
Harvey Harrisonf14df802008-07-02 11:05:35 -0700347 put_unaligned_be16(len_a, &aad[0]);
348 put_unaligned(mask_fc, (__le16 *)&aad[2]);
Harvey Harrison73e1f7c2008-07-02 11:05:34 -0700349 memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
Jiri Bencf0706e822007-05-05 11:45:53 -0700350
351 /* Mask Seq#, leave Frag# */
352 aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
353 aad[23] = 0;
Harvey Harrisonf14df802008-07-02 11:05:35 -0700354
Jiri Bencf0706e822007-05-05 11:45:53 -0700355 if (a4_included) {
Harvey Harrison73e1f7c2008-07-02 11:05:34 -0700356 memcpy(&aad[24], hdr->addr4, ETH_ALEN);
Harvey Harrisonf14df802008-07-02 11:05:35 -0700357 aad[30] = qos_tid;
Jiri Bencf0706e822007-05-05 11:45:53 -0700358 aad[31] = 0;
Harvey Harrisonf14df802008-07-02 11:05:35 -0700359 } else {
Harvey Harrison73e1f7c2008-07-02 11:05:34 -0700360 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
Harvey Harrisonf14df802008-07-02 11:05:35 -0700361 aad[24] = qos_tid;
Jiri Bencf0706e822007-05-05 11:45:53 -0700362 }
363}
364
365
366static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
367{
368 hdr[0] = pn[5];
369 hdr[1] = pn[4];
370 hdr[2] = 0;
371 hdr[3] = 0x20 | (key_id << 6);
372 hdr[4] = pn[3];
373 hdr[5] = pn[2];
374 hdr[6] = pn[1];
375 hdr[7] = pn[0];
376}
377
378
Johannes Bergc6a1fa12008-10-07 12:04:32 +0200379static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr)
Jiri Bencf0706e822007-05-05 11:45:53 -0700380{
381 pn[0] = hdr[7];
382 pn[1] = hdr[6];
383 pn[2] = hdr[5];
384 pn[3] = hdr[4];
385 pn[4] = hdr[1];
386 pn[5] = hdr[0];
Jiri Bencf0706e822007-05-05 11:45:53 -0700387}
388
389
Johannes Berge039fa42008-05-15 12:55:29 +0200390static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
Jiri Bencf0706e822007-05-05 11:45:53 -0700391{
392 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
393 struct ieee80211_key *key = tx->key;
Johannes Berge039fa42008-05-15 12:55:29 +0200394 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
Johannes Berg23c07522008-05-29 10:38:53 +0200395 int hdrlen, len, tail;
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200396 u8 *pos;
397 u8 pn[6];
398 u64 pn64;
Johannes Berg0cd20a22011-07-06 22:02:14 +0200399 u8 scratch[6 * AES_BLOCK_SIZE];
Jouni Malinen1f7d77a2009-01-08 13:32:10 +0200400
Johannes Berg813d7662010-01-17 01:47:58 +0100401 if (info->control.hw_key &&
Arik Nemtsov077a9152011-10-23 08:21:41 +0200402 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
403 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)) {
Johannes Berg813d7662010-01-17 01:47:58 +0100404 /*
405 * hwaccel has no need for preallocated room for CCMP
406 * header or MIC fields
407 */
Johannes Berg23c07522008-05-29 10:38:53 +0200408 return 0;
Johannes Berge039fa42008-05-15 12:55:29 +0200409 }
410
Harvey Harrisond5184ca2008-06-11 14:21:58 -0700411 hdrlen = ieee80211_hdrlen(hdr->frame_control);
Jiri Bencf0706e822007-05-05 11:45:53 -0700412 len = skb->len - hdrlen;
413
Johannes Berg813d7662010-01-17 01:47:58 +0100414 if (info->control.hw_key)
Johannes Berg23c07522008-05-29 10:38:53 +0200415 tail = 0;
Johannes Berg11a843b2007-08-28 17:01:55 -0400416 else
Johannes Berg23c07522008-05-29 10:38:53 +0200417 tail = CCMP_MIC_LEN;
Jiri Bencf0706e822007-05-05 11:45:53 -0700418
Johannes Berg23c07522008-05-29 10:38:53 +0200419 if (WARN_ON(skb_tailroom(skb) < tail ||
420 skb_headroom(skb) < CCMP_HDR_LEN))
421 return -1;
Jiri Bencf0706e822007-05-05 11:45:53 -0700422
423 pos = skb_push(skb, CCMP_HDR_LEN);
424 memmove(pos, pos + CCMP_HDR_LEN, hdrlen);
Arik Nemtsov077a9152011-10-23 08:21:41 +0200425
426 /* the HW only needs room for the IV, but not the actual IV */
Arik Nemtsove0830f72011-11-10 09:35:13 +0200427 if (info->control.hw_key &&
428 (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
Arik Nemtsov077a9152011-10-23 08:21:41 +0200429 return 0;
430
Jiri Bencf0706e822007-05-05 11:45:53 -0700431 hdr = (struct ieee80211_hdr *) pos;
432 pos += hdrlen;
433
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200434 pn64 = atomic64_inc_return(&key->u.ccmp.tx_pn);
Jiri Bencf0706e822007-05-05 11:45:53 -0700435
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200436 pn[5] = pn64;
437 pn[4] = pn64 >> 8;
438 pn[3] = pn64 >> 16;
439 pn[2] = pn64 >> 24;
440 pn[1] = pn64 >> 32;
441 pn[0] = pn64 >> 40;
Jiri Bencf0706e822007-05-05 11:45:53 -0700442
Johannes Berg8f20fc22007-08-28 17:01:54 -0400443 ccmp_pn2hdr(pos, pn, key->conf.keyidx);
Jiri Bencf0706e822007-05-05 11:45:53 -0700444
Johannes Berg813d7662010-01-17 01:47:58 +0100445 /* hwaccel - with software CCMP header */
446 if (info->control.hw_key)
Jiri Bencf0706e822007-05-05 11:45:53 -0700447 return 0;
Jiri Bencf0706e822007-05-05 11:45:53 -0700448
449 pos += CCMP_HDR_LEN;
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200450 ccmp_special_blocks(skb, pn, scratch, 0);
451 ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, scratch, pos, len,
Jiri Bencf0706e822007-05-05 11:45:53 -0700452 pos, skb_put(skb, CCMP_MIC_LEN));
453
454 return 0;
455}
456
457
Johannes Berg9ae54c82008-01-31 19:48:20 +0100458ieee80211_tx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100459ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx)
Jiri Bencf0706e822007-05-05 11:45:53 -0700460{
Johannes Berg252b86c2011-11-16 15:28:55 +0100461 struct sk_buff *skb;
Jiri Bencf0706e822007-05-05 11:45:53 -0700462
Johannes Berg5cf121c2008-02-25 16:27:43 +0100463 ieee80211_tx_set_protected(tx);
Jiri Bencf0706e822007-05-05 11:45:53 -0700464
Johannes Berg252b86c2011-11-16 15:28:55 +0100465 skb_queue_walk(&tx->skbs, skb) {
Johannes Berg2de8e0d2009-03-23 17:28:35 +0100466 if (ccmp_encrypt_skb(tx, skb) < 0)
467 return TX_DROP;
Johannes Berg252b86c2011-11-16 15:28:55 +0100468 }
Jiri Bencf0706e822007-05-05 11:45:53 -0700469
Johannes Berg9ae54c82008-01-31 19:48:20 +0100470 return TX_CONTINUE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700471}
472
473
Johannes Berg9ae54c82008-01-31 19:48:20 +0100474ieee80211_rx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100475ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx)
Jiri Bencf0706e822007-05-05 11:45:53 -0700476{
Harvey Harrisonc34498b2008-07-02 16:30:52 -0700477 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
Jiri Bencf0706e822007-05-05 11:45:53 -0700478 int hdrlen;
479 struct ieee80211_key *key = rx->key;
480 struct sk_buff *skb = rx->skb;
Johannes Bergeb9fb5b2009-11-16 13:58:20 +0100481 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
Jiri Bencf0706e822007-05-05 11:45:53 -0700482 u8 pn[CCMP_PN_LEN];
483 int data_len;
Jouni Malinen91902522010-06-11 10:27:33 -0700484 int queue;
Jiri Bencf0706e822007-05-05 11:45:53 -0700485
Harvey Harrisond5184ca2008-06-11 14:21:58 -0700486 hdrlen = ieee80211_hdrlen(hdr->frame_control);
Jiri Bencf0706e822007-05-05 11:45:53 -0700487
Jouni Malinenfb733332009-01-08 13:32:00 +0200488 if (!ieee80211_is_data(hdr->frame_control) &&
489 !ieee80211_is_robust_mgmt_frame(hdr))
Johannes Berg9ae54c82008-01-31 19:48:20 +0100490 return RX_CONTINUE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700491
492 data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN;
493 if (!rx->sta || data_len < 0)
Johannes Berge4c26ad2008-01-31 19:48:21 +0100494 return RX_DROP_UNUSABLE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700495
Johannes Berga8286912012-03-12 13:49:14 +0100496 if (status->flag & RX_FLAG_DECRYPTED) {
497 if (!pskb_may_pull(rx->skb, hdrlen + CCMP_HDR_LEN))
498 return RX_DROP_UNUSABLE;
499 } else {
500 if (skb_linearize(rx->skb))
501 return RX_DROP_UNUSABLE;
502 }
503
Johannes Bergc6a1fa12008-10-07 12:04:32 +0200504 ccmp_hdr2pn(pn, skb->data + hdrlen);
Jiri Bencf0706e822007-05-05 11:45:53 -0700505
Johannes Berg9e262972011-07-07 18:45:03 +0200506 queue = rx->security_idx;
Jouni Malinen91902522010-06-11 10:27:33 -0700507
508 if (memcmp(pn, key->u.ccmp.rx_pn[queue], CCMP_PN_LEN) <= 0) {
Jiri Bencf0706e822007-05-05 11:45:53 -0700509 key->u.ccmp.replays++;
Johannes Berge4c26ad2008-01-31 19:48:21 +0100510 return RX_DROP_UNUSABLE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700511 }
512
Johannes Bergeb9fb5b2009-11-16 13:58:20 +0100513 if (!(status->flag & RX_FLAG_DECRYPTED)) {
Johannes Berg0cd20a22011-07-06 22:02:14 +0200514 u8 scratch[6 * AES_BLOCK_SIZE];
Johannes Berg7848ba72007-09-14 11:10:25 -0400515 /* hardware didn't decrypt/verify MIC */
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200516 ccmp_special_blocks(skb, pn, scratch, 1);
Jiri Bencf0706e822007-05-05 11:45:53 -0700517
518 if (ieee80211_aes_ccm_decrypt(
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200519 key->u.ccmp.tfm, scratch,
Jiri Bencf0706e822007-05-05 11:45:53 -0700520 skb->data + hdrlen + CCMP_HDR_LEN, data_len,
521 skb->data + skb->len - CCMP_MIC_LEN,
Johannes Bergc6a1fa12008-10-07 12:04:32 +0200522 skb->data + hdrlen + CCMP_HDR_LEN))
Johannes Berge4c26ad2008-01-31 19:48:21 +0100523 return RX_DROP_UNUSABLE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700524 }
525
Jouni Malinen91902522010-06-11 10:27:33 -0700526 memcpy(key->u.ccmp.rx_pn[queue], pn, CCMP_PN_LEN);
Jiri Bencf0706e822007-05-05 11:45:53 -0700527
528 /* Remove CCMP header and MIC */
Johannes Berga8286912012-03-12 13:49:14 +0100529 if (pskb_trim(skb, skb->len - CCMP_MIC_LEN))
530 return RX_DROP_UNUSABLE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700531 memmove(skb->data + CCMP_HDR_LEN, skb->data, hdrlen);
532 skb_pull(skb, CCMP_HDR_LEN);
533
Johannes Berg9ae54c82008-01-31 19:48:20 +0100534 return RX_CONTINUE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700535}
Jouni Malinen765cb462009-01-08 13:32:01 +0200536
537
538static void bip_aad(struct sk_buff *skb, u8 *aad)
539{
540 /* BIP AAD: FC(masked) || A1 || A2 || A3 */
541
542 /* FC type/subtype */
543 aad[0] = skb->data[0];
544 /* Mask FC Retry, PwrMgt, MoreData flags to zero */
545 aad[1] = skb->data[1] & ~(BIT(4) | BIT(5) | BIT(6));
546 /* A1 || A2 || A3 */
547 memcpy(aad + 2, skb->data + 4, 3 * ETH_ALEN);
548}
549
550
Johannes Berg75396ae2011-07-06 22:00:35 +0200551static inline void bip_ipn_set64(u8 *d, u64 pn)
552{
553 *d++ = pn;
554 *d++ = pn >> 8;
555 *d++ = pn >> 16;
556 *d++ = pn >> 24;
557 *d++ = pn >> 32;
558 *d = pn >> 40;
559}
560
Jouni Malinen765cb462009-01-08 13:32:01 +0200561static inline void bip_ipn_swap(u8 *d, const u8 *s)
562{
563 *d++ = s[5];
564 *d++ = s[4];
565 *d++ = s[3];
566 *d++ = s[2];
567 *d++ = s[1];
568 *d = s[0];
569}
570
571
572ieee80211_tx_result
573ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
574{
Johannes Berg252b86c2011-11-16 15:28:55 +0100575 struct sk_buff *skb;
576 struct ieee80211_tx_info *info;
Jouni Malinen765cb462009-01-08 13:32:01 +0200577 struct ieee80211_key *key = tx->key;
578 struct ieee80211_mmie *mmie;
Johannes Berg75396ae2011-07-06 22:00:35 +0200579 u8 aad[20];
580 u64 pn64;
Jouni Malinen765cb462009-01-08 13:32:01 +0200581
Johannes Berg252b86c2011-11-16 15:28:55 +0100582 if (WARN_ON(skb_queue_len(&tx->skbs) != 1))
583 return TX_DROP;
584
585 skb = skb_peek(&tx->skbs);
586
587 info = IEEE80211_SKB_CB(skb);
588
Johannes Berg813d7662010-01-17 01:47:58 +0100589 if (info->control.hw_key)
Johannes Berg252b86c2011-11-16 15:28:55 +0100590 return TX_CONTINUE;
Jouni Malinen765cb462009-01-08 13:32:01 +0200591
592 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
593 return TX_DROP;
594
595 mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie));
596 mmie->element_id = WLAN_EID_MMIE;
597 mmie->length = sizeof(*mmie) - 2;
598 mmie->key_id = cpu_to_le16(key->conf.keyidx);
599
600 /* PN = PN + 1 */
Johannes Berg75396ae2011-07-06 22:00:35 +0200601 pn64 = atomic64_inc_return(&key->u.aes_cmac.tx_pn);
Jouni Malinen765cb462009-01-08 13:32:01 +0200602
Johannes Berg75396ae2011-07-06 22:00:35 +0200603 bip_ipn_set64(mmie->sequence_number, pn64);
Jouni Malinen765cb462009-01-08 13:32:01 +0200604
605 bip_aad(skb, aad);
606
607 /*
608 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
609 */
Johannes Berg75396ae2011-07-06 22:00:35 +0200610 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
611 skb->data + 24, skb->len - 24, mmie->mic);
Jouni Malinen765cb462009-01-08 13:32:01 +0200612
613 return TX_CONTINUE;
614}
615
616
617ieee80211_rx_result
618ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
619{
620 struct sk_buff *skb = rx->skb;
Johannes Bergeb9fb5b2009-11-16 13:58:20 +0100621 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
Jouni Malinen765cb462009-01-08 13:32:01 +0200622 struct ieee80211_key *key = rx->key;
623 struct ieee80211_mmie *mmie;
624 u8 aad[20], mic[8], ipn[6];
625 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
626
627 if (!ieee80211_is_mgmt(hdr->frame_control))
628 return RX_CONTINUE;
629
Johannes Berga8286912012-03-12 13:49:14 +0100630 /* management frames are already linear */
631
Jouni Malinen765cb462009-01-08 13:32:01 +0200632 if (skb->len < 24 + sizeof(*mmie))
633 return RX_DROP_UNUSABLE;
634
635 mmie = (struct ieee80211_mmie *)
636 (skb->data + skb->len - sizeof(*mmie));
637 if (mmie->element_id != WLAN_EID_MMIE ||
638 mmie->length != sizeof(*mmie) - 2)
639 return RX_DROP_UNUSABLE; /* Invalid MMIE */
640
641 bip_ipn_swap(ipn, mmie->sequence_number);
642
643 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
644 key->u.aes_cmac.replays++;
645 return RX_DROP_UNUSABLE;
646 }
647
Johannes Bergeb9fb5b2009-11-16 13:58:20 +0100648 if (!(status->flag & RX_FLAG_DECRYPTED)) {
Jouni Malinen765cb462009-01-08 13:32:01 +0200649 /* hardware didn't decrypt/verify MIC */
650 bip_aad(skb, aad);
Johannes Berg75396ae2011-07-06 22:00:35 +0200651 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
Jouni Malinen765cb462009-01-08 13:32:01 +0200652 skb->data + 24, skb->len - 24, mic);
653 if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
654 key->u.aes_cmac.icverrors++;
655 return RX_DROP_UNUSABLE;
656 }
657 }
658
659 memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
660
661 /* Remove MMIE */
662 skb_trim(skb, skb->len - sizeof(*mmie));
663
664 return RX_CONTINUE;
665}
Yoni Divinskyd32a1022012-01-16 15:18:59 +0200666
667ieee80211_tx_result
668ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx)
669{
670 struct sk_buff *skb;
671 struct ieee80211_tx_info *info = NULL;
672
673 skb_queue_walk(&tx->skbs, skb) {
674 info = IEEE80211_SKB_CB(skb);
675
676 /* handle hw-only algorithm */
677 if (!info->control.hw_key)
678 return TX_DROP;
679 }
680
681 ieee80211_tx_set_protected(tx);
682
683 return TX_CONTINUE;
684}