blob: f614ce7bb6e3b4aea4f9c445e2594b2c6366e6d0 [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
109 if (!(status->flag & RX_FLAG_IV_STRIPPED))
110 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
Harvey Harrison8e8862b2008-07-02 11:05:35 -0700141 data = skb->data + hdrlen;
142 data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
Jouni Malinen747d7532011-02-03 18:34:28 +0200143 key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY];
Harvey Harrison8e8862b2008-07-02 11:05:35 -0700144 michael_mic(key, hdr, data, data_len, mic);
Christian Lamparter816c04f2011-04-30 15:24:30 +0200145 if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0)
146 goto mic_fail;
Jiri Bencf0706e822007-05-05 11:45:53 -0700147
Jiri Bencf0706e822007-05-05 11:45:53 -0700148 /* remove Michael MIC from payload */
149 skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
150
Christian Lamparter816c04f2011-04-30 15:24:30 +0200151update_iv:
Johannes Berg50741ae2007-09-26 15:19:45 +0200152 /* update IV in key information to be able to detect replays */
Johannes Berg9e262972011-07-07 18:45:03 +0200153 rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip_iv32;
154 rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip_iv16;
Johannes Berg50741ae2007-09-26 15:19:45 +0200155
Johannes Berg9ae54c82008-01-31 19:48:20 +0100156 return RX_CONTINUE;
Christian Lamparter816c04f2011-04-30 15:24:30 +0200157
158mic_fail:
Arik Nemtsova66b98d2011-06-23 00:00:24 +0300159 /*
160 * In some cases the key can be unset - e.g. a multicast packet, in
161 * a driver that supports HW encryption. Send up the key idx only if
162 * the key is set.
163 */
164 mac80211_ev_michael_mic_failure(rx->sdata,
165 rx->key ? rx->key->conf.keyidx : -1,
Christian Lamparter816c04f2011-04-30 15:24:30 +0200166 (void *) skb->data, NULL, GFP_ATOMIC);
167 return RX_DROP_UNUSABLE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700168}
169
170
Johannes Berge039fa42008-05-15 12:55:29 +0200171static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
Jiri Bencf0706e822007-05-05 11:45:53 -0700172{
173 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
174 struct ieee80211_key *key = tx->key;
Johannes Berge039fa42008-05-15 12:55:29 +0200175 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
Johannes Berg523b02e2011-07-07 22:28:01 +0200176 unsigned long flags;
Harvey Harrisond5184ca2008-06-11 14:21:58 -0700177 unsigned int hdrlen;
178 int len, tail;
Jiri Bencf0706e822007-05-05 11:45:53 -0700179 u8 *pos;
180
Johannes Berg813d7662010-01-17 01:47:58 +0100181 if (info->control.hw_key &&
182 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV)) {
183 /* hwaccel - with no need for software-generated IV */
Johannes Berg23c07522008-05-29 10:38:53 +0200184 return 0;
Johannes Berge039fa42008-05-15 12:55:29 +0200185 }
186
Harvey Harrisond5184ca2008-06-11 14:21:58 -0700187 hdrlen = ieee80211_hdrlen(hdr->frame_control);
Jiri Bencf0706e822007-05-05 11:45:53 -0700188 len = skb->len - hdrlen;
189
Johannes Berg813d7662010-01-17 01:47:58 +0100190 if (info->control.hw_key)
Johannes Berg23c07522008-05-29 10:38:53 +0200191 tail = 0;
Johannes Berg11a843b2007-08-28 17:01:55 -0400192 else
Johannes Berg23c07522008-05-29 10:38:53 +0200193 tail = TKIP_ICV_LEN;
Johannes Berg8f20fc22007-08-28 17:01:54 -0400194
Johannes Berg23c07522008-05-29 10:38:53 +0200195 if (WARN_ON(skb_tailroom(skb) < tail ||
196 skb_headroom(skb) < TKIP_IV_LEN))
197 return -1;
Jiri Bencf0706e822007-05-05 11:45:53 -0700198
199 pos = skb_push(skb, TKIP_IV_LEN);
200 memmove(pos, pos + TKIP_IV_LEN, hdrlen);
201 pos += hdrlen;
202
203 /* Increase IV for the frame */
Johannes Berg523b02e2011-07-07 22:28:01 +0200204 spin_lock_irqsave(&key->u.tkip.txlock, flags);
Harvey Harrisonb0f76b32008-05-14 16:26:19 -0700205 key->u.tkip.tx.iv16++;
206 if (key->u.tkip.tx.iv16 == 0)
207 key->u.tkip.tx.iv32++;
Johannes Berg523b02e2011-07-07 22:28:01 +0200208 pos = ieee80211_tkip_add_iv(pos, key);
209 spin_unlock_irqrestore(&key->u.tkip.txlock, flags);
Jiri Bencf0706e822007-05-05 11:45:53 -0700210
Johannes Berg813d7662010-01-17 01:47:58 +0100211 /* hwaccel - with software IV */
212 if (info->control.hw_key)
Jiri Bencf0706e822007-05-05 11:45:53 -0700213 return 0;
Jiri Bencf0706e822007-05-05 11:45:53 -0700214
215 /* Add room for ICV */
216 skb_put(skb, TKIP_ICV_LEN);
217
John W. Linville34731872010-07-07 15:07:49 -0400218 return ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
Johannes Berg523b02e2011-07-07 22:28:01 +0200219 key, skb, pos, len);
Jiri Bencf0706e822007-05-05 11:45:53 -0700220}
221
222
Johannes Berg9ae54c82008-01-31 19:48:20 +0100223ieee80211_tx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100224ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
Jiri Bencf0706e822007-05-05 11:45:53 -0700225{
Jiri Bencf0706e822007-05-05 11:45:53 -0700226 struct sk_buff *skb = tx->skb;
Jiri Bencf0706e822007-05-05 11:45:53 -0700227
Johannes Berg5cf121c2008-02-25 16:27:43 +0100228 ieee80211_tx_set_protected(tx);
Jiri Bencf0706e822007-05-05 11:45:53 -0700229
Johannes Berg2de8e0d2009-03-23 17:28:35 +0100230 do {
231 if (tkip_encrypt_skb(tx, skb) < 0)
232 return TX_DROP;
233 } while ((skb = skb->next));
Jiri Bencf0706e822007-05-05 11:45:53 -0700234
Johannes Berg9ae54c82008-01-31 19:48:20 +0100235 return TX_CONTINUE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700236}
237
238
Johannes Berg9ae54c82008-01-31 19:48:20 +0100239ieee80211_rx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100240ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
Jiri Bencf0706e822007-05-05 11:45:53 -0700241{
242 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
Jouni Malinen747d7532011-02-03 18:34:28 +0200243 int hdrlen, res, hwaccel = 0;
Jiri Bencf0706e822007-05-05 11:45:53 -0700244 struct ieee80211_key *key = rx->key;
245 struct sk_buff *skb = rx->skb;
Johannes Bergeb9fb5b2009-11-16 13:58:20 +0100246 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
Jiri Bencf0706e822007-05-05 11:45:53 -0700247
Harvey Harrisond5184ca2008-06-11 14:21:58 -0700248 hdrlen = ieee80211_hdrlen(hdr->frame_control);
Jiri Bencf0706e822007-05-05 11:45:53 -0700249
Harvey Harrisonc34498b2008-07-02 16:30:52 -0700250 if (!ieee80211_is_data(hdr->frame_control))
Johannes Berg9ae54c82008-01-31 19:48:20 +0100251 return RX_CONTINUE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700252
253 if (!rx->sta || skb->len - hdrlen < 12)
Johannes Berge4c26ad2008-01-31 19:48:21 +0100254 return RX_DROP_UNUSABLE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700255
Johannes Bergdc1580d2010-08-10 09:46:40 +0200256 /*
257 * Let TKIP code verify IV, but skip decryption.
258 * In the case where hardware checks the IV as well,
259 * we don't even get here, see ieee80211_rx_h_decrypt()
260 */
261 if (status->flag & RX_FLAG_DECRYPTED)
Jiri Bencf0706e822007-05-05 11:45:53 -0700262 hwaccel = 1;
Jiri Bencf0706e822007-05-05 11:45:53 -0700263
264 res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,
265 key, skb->data + hdrlen,
Johannes Berg17741cd2008-09-11 00:02:02 +0200266 skb->len - hdrlen, rx->sta->sta.addr,
Johannes Berg9e262972011-07-07 18:45:03 +0200267 hdr->addr1, hwaccel, rx->security_idx,
Johannes Berg5cf121c2008-02-25 16:27:43 +0100268 &rx->tkip_iv32,
269 &rx->tkip_iv16);
Jouni Malinen747d7532011-02-03 18:34:28 +0200270 if (res != TKIP_DECRYPT_OK)
Johannes Berge4c26ad2008-01-31 19:48:21 +0100271 return RX_DROP_UNUSABLE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700272
273 /* Trim ICV */
274 skb_trim(skb, skb->len - TKIP_ICV_LEN);
275
276 /* Remove IV */
277 memmove(skb->data + TKIP_IV_LEN, skb->data, hdrlen);
278 skb_pull(skb, TKIP_IV_LEN);
279
Johannes Berg9ae54c82008-01-31 19:48:20 +0100280 return RX_CONTINUE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700281}
282
283
Harvey Harrisonfeccb462008-07-02 16:30:52 -0700284static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *scratch,
Jiri Bencf0706e822007-05-05 11:45:53 -0700285 int encrypted)
286{
Harvey Harrisonf14df802008-07-02 11:05:35 -0700287 __le16 mask_fc;
Jouni Malinenfb733332009-01-08 13:32:00 +0200288 int a4_included, mgmt;
Harvey Harrisonf14df802008-07-02 11:05:35 -0700289 u8 qos_tid;
Harvey Harrisonfeccb462008-07-02 16:30:52 -0700290 u8 *b_0, *aad;
Harvey Harrisonf14df802008-07-02 11:05:35 -0700291 u16 data_len, len_a;
292 unsigned int hdrlen;
293 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
Jiri Bencf0706e822007-05-05 11:45:53 -0700294
Johannes Berg0cd20a22011-07-06 22:02:14 +0200295 memset(scratch, 0, 6 * AES_BLOCK_SIZE);
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200296
Johannes Berg0cd20a22011-07-06 22:02:14 +0200297 b_0 = scratch + 3 * AES_BLOCK_SIZE;
298 aad = scratch + 4 * AES_BLOCK_SIZE;
Harvey Harrisonfeccb462008-07-02 16:30:52 -0700299
Harvey Harrisonf14df802008-07-02 11:05:35 -0700300 /*
Jouni Malinenfb733332009-01-08 13:32:00 +0200301 * Mask FC: zero subtype b4 b5 b6 (if not mgmt)
Harvey Harrisonf14df802008-07-02 11:05:35 -0700302 * Retry, PwrMgt, MoreData; set Protected
303 */
Jouni Malinenfb733332009-01-08 13:32:00 +0200304 mgmt = ieee80211_is_mgmt(hdr->frame_control);
Harvey Harrisonf14df802008-07-02 11:05:35 -0700305 mask_fc = hdr->frame_control;
Jouni Malinenfb733332009-01-08 13:32:00 +0200306 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
Harvey Harrisonf14df802008-07-02 11:05:35 -0700307 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
Jouni Malinenfb733332009-01-08 13:32:00 +0200308 if (!mgmt)
309 mask_fc &= ~cpu_to_le16(0x0070);
Harvey Harrisonf14df802008-07-02 11:05:35 -0700310 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
Jiri Bencf0706e822007-05-05 11:45:53 -0700311
Harvey Harrisonf14df802008-07-02 11:05:35 -0700312 hdrlen = ieee80211_hdrlen(hdr->frame_control);
313 len_a = hdrlen - 2;
314 a4_included = ieee80211_has_a4(hdr->frame_control);
315
316 if (ieee80211_is_data_qos(hdr->frame_control))
317 qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
318 else
319 qos_tid = 0;
320
321 data_len = skb->len - hdrlen - CCMP_HDR_LEN;
322 if (encrypted)
323 data_len -= CCMP_MIC_LEN;
324
Jiri Bencf0706e822007-05-05 11:45:53 -0700325 /* First block, b_0 */
Jiri Bencf0706e822007-05-05 11:45:53 -0700326 b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */
Jouni Malinenfb733332009-01-08 13:32:00 +0200327 /* Nonce: Nonce Flags | A2 | PN
328 * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7)
329 */
330 b_0[1] = qos_tid | (mgmt << 4);
Harvey Harrison73e1f7c2008-07-02 11:05:34 -0700331 memcpy(&b_0[2], hdr->addr2, ETH_ALEN);
Jiri Bencf0706e822007-05-05 11:45:53 -0700332 memcpy(&b_0[8], pn, CCMP_PN_LEN);
333 /* l(m) */
Harvey Harrisonf14df802008-07-02 11:05:35 -0700334 put_unaligned_be16(data_len, &b_0[14]);
Jiri Bencf0706e822007-05-05 11:45:53 -0700335
336 /* AAD (extra authenticate-only data) / masked 802.11 header
337 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */
Harvey Harrisonf14df802008-07-02 11:05:35 -0700338 put_unaligned_be16(len_a, &aad[0]);
339 put_unaligned(mask_fc, (__le16 *)&aad[2]);
Harvey Harrison73e1f7c2008-07-02 11:05:34 -0700340 memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
Jiri Bencf0706e822007-05-05 11:45:53 -0700341
342 /* Mask Seq#, leave Frag# */
343 aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
344 aad[23] = 0;
Harvey Harrisonf14df802008-07-02 11:05:35 -0700345
Jiri Bencf0706e822007-05-05 11:45:53 -0700346 if (a4_included) {
Harvey Harrison73e1f7c2008-07-02 11:05:34 -0700347 memcpy(&aad[24], hdr->addr4, ETH_ALEN);
Harvey Harrisonf14df802008-07-02 11:05:35 -0700348 aad[30] = qos_tid;
Jiri Bencf0706e822007-05-05 11:45:53 -0700349 aad[31] = 0;
Harvey Harrisonf14df802008-07-02 11:05:35 -0700350 } else {
Harvey Harrison73e1f7c2008-07-02 11:05:34 -0700351 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
Harvey Harrisonf14df802008-07-02 11:05:35 -0700352 aad[24] = qos_tid;
Jiri Bencf0706e822007-05-05 11:45:53 -0700353 }
354}
355
356
357static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
358{
359 hdr[0] = pn[5];
360 hdr[1] = pn[4];
361 hdr[2] = 0;
362 hdr[3] = 0x20 | (key_id << 6);
363 hdr[4] = pn[3];
364 hdr[5] = pn[2];
365 hdr[6] = pn[1];
366 hdr[7] = pn[0];
367}
368
369
Johannes Bergc6a1fa12008-10-07 12:04:32 +0200370static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr)
Jiri Bencf0706e822007-05-05 11:45:53 -0700371{
372 pn[0] = hdr[7];
373 pn[1] = hdr[6];
374 pn[2] = hdr[5];
375 pn[3] = hdr[4];
376 pn[4] = hdr[1];
377 pn[5] = hdr[0];
Jiri Bencf0706e822007-05-05 11:45:53 -0700378}
379
380
Johannes Berge039fa42008-05-15 12:55:29 +0200381static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
Jiri Bencf0706e822007-05-05 11:45:53 -0700382{
383 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
384 struct ieee80211_key *key = tx->key;
Johannes Berge039fa42008-05-15 12:55:29 +0200385 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
Johannes Berg23c07522008-05-29 10:38:53 +0200386 int hdrlen, len, tail;
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200387 u8 *pos;
388 u8 pn[6];
389 u64 pn64;
Johannes Berg0cd20a22011-07-06 22:02:14 +0200390 u8 scratch[6 * AES_BLOCK_SIZE];
Jouni Malinen1f7d77a2009-01-08 13:32:10 +0200391
Johannes Berg813d7662010-01-17 01:47:58 +0100392 if (info->control.hw_key &&
393 !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV)) {
394 /*
395 * hwaccel has no need for preallocated room for CCMP
396 * header or MIC fields
397 */
Johannes Berg23c07522008-05-29 10:38:53 +0200398 return 0;
Johannes Berge039fa42008-05-15 12:55:29 +0200399 }
400
Harvey Harrisond5184ca2008-06-11 14:21:58 -0700401 hdrlen = ieee80211_hdrlen(hdr->frame_control);
Jiri Bencf0706e822007-05-05 11:45:53 -0700402 len = skb->len - hdrlen;
403
Johannes Berg813d7662010-01-17 01:47:58 +0100404 if (info->control.hw_key)
Johannes Berg23c07522008-05-29 10:38:53 +0200405 tail = 0;
Johannes Berg11a843b2007-08-28 17:01:55 -0400406 else
Johannes Berg23c07522008-05-29 10:38:53 +0200407 tail = CCMP_MIC_LEN;
Jiri Bencf0706e822007-05-05 11:45:53 -0700408
Johannes Berg23c07522008-05-29 10:38:53 +0200409 if (WARN_ON(skb_tailroom(skb) < tail ||
410 skb_headroom(skb) < CCMP_HDR_LEN))
411 return -1;
Jiri Bencf0706e822007-05-05 11:45:53 -0700412
413 pos = skb_push(skb, CCMP_HDR_LEN);
414 memmove(pos, pos + CCMP_HDR_LEN, hdrlen);
415 hdr = (struct ieee80211_hdr *) pos;
416 pos += hdrlen;
417
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200418 pn64 = atomic64_inc_return(&key->u.ccmp.tx_pn);
Jiri Bencf0706e822007-05-05 11:45:53 -0700419
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200420 pn[5] = pn64;
421 pn[4] = pn64 >> 8;
422 pn[3] = pn64 >> 16;
423 pn[2] = pn64 >> 24;
424 pn[1] = pn64 >> 32;
425 pn[0] = pn64 >> 40;
Jiri Bencf0706e822007-05-05 11:45:53 -0700426
Johannes Berg8f20fc22007-08-28 17:01:54 -0400427 ccmp_pn2hdr(pos, pn, key->conf.keyidx);
Jiri Bencf0706e822007-05-05 11:45:53 -0700428
Johannes Berg813d7662010-01-17 01:47:58 +0100429 /* hwaccel - with software CCMP header */
430 if (info->control.hw_key)
Jiri Bencf0706e822007-05-05 11:45:53 -0700431 return 0;
Jiri Bencf0706e822007-05-05 11:45:53 -0700432
433 pos += CCMP_HDR_LEN;
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200434 ccmp_special_blocks(skb, pn, scratch, 0);
435 ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, scratch, pos, len,
Jiri Bencf0706e822007-05-05 11:45:53 -0700436 pos, skb_put(skb, CCMP_MIC_LEN));
437
438 return 0;
439}
440
441
Johannes Berg9ae54c82008-01-31 19:48:20 +0100442ieee80211_tx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100443ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx)
Jiri Bencf0706e822007-05-05 11:45:53 -0700444{
Jiri Bencf0706e822007-05-05 11:45:53 -0700445 struct sk_buff *skb = tx->skb;
Jiri Bencf0706e822007-05-05 11:45:53 -0700446
Johannes Berg5cf121c2008-02-25 16:27:43 +0100447 ieee80211_tx_set_protected(tx);
Jiri Bencf0706e822007-05-05 11:45:53 -0700448
Johannes Berg2de8e0d2009-03-23 17:28:35 +0100449 do {
450 if (ccmp_encrypt_skb(tx, skb) < 0)
451 return TX_DROP;
452 } while ((skb = skb->next));
Jiri Bencf0706e822007-05-05 11:45:53 -0700453
Johannes Berg9ae54c82008-01-31 19:48:20 +0100454 return TX_CONTINUE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700455}
456
457
Johannes Berg9ae54c82008-01-31 19:48:20 +0100458ieee80211_rx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100459ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx)
Jiri Bencf0706e822007-05-05 11:45:53 -0700460{
Harvey Harrisonc34498b2008-07-02 16:30:52 -0700461 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
Jiri Bencf0706e822007-05-05 11:45:53 -0700462 int hdrlen;
463 struct ieee80211_key *key = rx->key;
464 struct sk_buff *skb = rx->skb;
Johannes Bergeb9fb5b2009-11-16 13:58:20 +0100465 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
Jiri Bencf0706e822007-05-05 11:45:53 -0700466 u8 pn[CCMP_PN_LEN];
467 int data_len;
Jouni Malinen91902522010-06-11 10:27:33 -0700468 int queue;
Jiri Bencf0706e822007-05-05 11:45:53 -0700469
Harvey Harrisond5184ca2008-06-11 14:21:58 -0700470 hdrlen = ieee80211_hdrlen(hdr->frame_control);
Jiri Bencf0706e822007-05-05 11:45:53 -0700471
Jouni Malinenfb733332009-01-08 13:32:00 +0200472 if (!ieee80211_is_data(hdr->frame_control) &&
473 !ieee80211_is_robust_mgmt_frame(hdr))
Johannes Berg9ae54c82008-01-31 19:48:20 +0100474 return RX_CONTINUE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700475
476 data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN;
477 if (!rx->sta || data_len < 0)
Johannes Berge4c26ad2008-01-31 19:48:21 +0100478 return RX_DROP_UNUSABLE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700479
Johannes Bergc6a1fa12008-10-07 12:04:32 +0200480 ccmp_hdr2pn(pn, skb->data + hdrlen);
Jiri Bencf0706e822007-05-05 11:45:53 -0700481
Johannes Berg9e262972011-07-07 18:45:03 +0200482 queue = rx->security_idx;
Jouni Malinen91902522010-06-11 10:27:33 -0700483
484 if (memcmp(pn, key->u.ccmp.rx_pn[queue], CCMP_PN_LEN) <= 0) {
Jiri Bencf0706e822007-05-05 11:45:53 -0700485 key->u.ccmp.replays++;
Johannes Berge4c26ad2008-01-31 19:48:21 +0100486 return RX_DROP_UNUSABLE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700487 }
488
Johannes Bergeb9fb5b2009-11-16 13:58:20 +0100489 if (!(status->flag & RX_FLAG_DECRYPTED)) {
Johannes Berg0cd20a22011-07-06 22:02:14 +0200490 u8 scratch[6 * AES_BLOCK_SIZE];
Johannes Berg7848ba72007-09-14 11:10:25 -0400491 /* hardware didn't decrypt/verify MIC */
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200492 ccmp_special_blocks(skb, pn, scratch, 1);
Jiri Bencf0706e822007-05-05 11:45:53 -0700493
494 if (ieee80211_aes_ccm_decrypt(
Johannes Bergaba83a0b2011-07-06 21:59:39 +0200495 key->u.ccmp.tfm, scratch,
Jiri Bencf0706e822007-05-05 11:45:53 -0700496 skb->data + hdrlen + CCMP_HDR_LEN, data_len,
497 skb->data + skb->len - CCMP_MIC_LEN,
Johannes Bergc6a1fa12008-10-07 12:04:32 +0200498 skb->data + hdrlen + CCMP_HDR_LEN))
Johannes Berge4c26ad2008-01-31 19:48:21 +0100499 return RX_DROP_UNUSABLE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700500 }
501
Jouni Malinen91902522010-06-11 10:27:33 -0700502 memcpy(key->u.ccmp.rx_pn[queue], pn, CCMP_PN_LEN);
Jiri Bencf0706e822007-05-05 11:45:53 -0700503
504 /* Remove CCMP header and MIC */
505 skb_trim(skb, skb->len - CCMP_MIC_LEN);
506 memmove(skb->data + CCMP_HDR_LEN, skb->data, hdrlen);
507 skb_pull(skb, CCMP_HDR_LEN);
508
Johannes Berg9ae54c82008-01-31 19:48:20 +0100509 return RX_CONTINUE;
Jiri Bencf0706e822007-05-05 11:45:53 -0700510}
Jouni Malinen765cb462009-01-08 13:32:01 +0200511
512
513static void bip_aad(struct sk_buff *skb, u8 *aad)
514{
515 /* BIP AAD: FC(masked) || A1 || A2 || A3 */
516
517 /* FC type/subtype */
518 aad[0] = skb->data[0];
519 /* Mask FC Retry, PwrMgt, MoreData flags to zero */
520 aad[1] = skb->data[1] & ~(BIT(4) | BIT(5) | BIT(6));
521 /* A1 || A2 || A3 */
522 memcpy(aad + 2, skb->data + 4, 3 * ETH_ALEN);
523}
524
525
Johannes Berg75396ae2011-07-06 22:00:35 +0200526static inline void bip_ipn_set64(u8 *d, u64 pn)
527{
528 *d++ = pn;
529 *d++ = pn >> 8;
530 *d++ = pn >> 16;
531 *d++ = pn >> 24;
532 *d++ = pn >> 32;
533 *d = pn >> 40;
534}
535
Jouni Malinen765cb462009-01-08 13:32:01 +0200536static inline void bip_ipn_swap(u8 *d, const u8 *s)
537{
538 *d++ = s[5];
539 *d++ = s[4];
540 *d++ = s[3];
541 *d++ = s[2];
542 *d++ = s[1];
543 *d = s[0];
544}
545
546
547ieee80211_tx_result
548ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
549{
550 struct sk_buff *skb = tx->skb;
551 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
552 struct ieee80211_key *key = tx->key;
553 struct ieee80211_mmie *mmie;
Johannes Berg75396ae2011-07-06 22:00:35 +0200554 u8 aad[20];
555 u64 pn64;
Jouni Malinen765cb462009-01-08 13:32:01 +0200556
Johannes Berg813d7662010-01-17 01:47:58 +0100557 if (info->control.hw_key)
Jouni Malinen765cb462009-01-08 13:32:01 +0200558 return 0;
Jouni Malinen765cb462009-01-08 13:32:01 +0200559
560 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
561 return TX_DROP;
562
563 mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie));
564 mmie->element_id = WLAN_EID_MMIE;
565 mmie->length = sizeof(*mmie) - 2;
566 mmie->key_id = cpu_to_le16(key->conf.keyidx);
567
568 /* PN = PN + 1 */
Johannes Berg75396ae2011-07-06 22:00:35 +0200569 pn64 = atomic64_inc_return(&key->u.aes_cmac.tx_pn);
Jouni Malinen765cb462009-01-08 13:32:01 +0200570
Johannes Berg75396ae2011-07-06 22:00:35 +0200571 bip_ipn_set64(mmie->sequence_number, pn64);
Jouni Malinen765cb462009-01-08 13:32:01 +0200572
573 bip_aad(skb, aad);
574
575 /*
576 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
577 */
Johannes Berg75396ae2011-07-06 22:00:35 +0200578 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
579 skb->data + 24, skb->len - 24, mmie->mic);
Jouni Malinen765cb462009-01-08 13:32:01 +0200580
581 return TX_CONTINUE;
582}
583
584
585ieee80211_rx_result
586ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
587{
588 struct sk_buff *skb = rx->skb;
Johannes Bergeb9fb5b2009-11-16 13:58:20 +0100589 struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
Jouni Malinen765cb462009-01-08 13:32:01 +0200590 struct ieee80211_key *key = rx->key;
591 struct ieee80211_mmie *mmie;
592 u8 aad[20], mic[8], ipn[6];
593 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
594
595 if (!ieee80211_is_mgmt(hdr->frame_control))
596 return RX_CONTINUE;
597
Jouni Malinen765cb462009-01-08 13:32:01 +0200598 if (skb->len < 24 + sizeof(*mmie))
599 return RX_DROP_UNUSABLE;
600
601 mmie = (struct ieee80211_mmie *)
602 (skb->data + skb->len - sizeof(*mmie));
603 if (mmie->element_id != WLAN_EID_MMIE ||
604 mmie->length != sizeof(*mmie) - 2)
605 return RX_DROP_UNUSABLE; /* Invalid MMIE */
606
607 bip_ipn_swap(ipn, mmie->sequence_number);
608
609 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
610 key->u.aes_cmac.replays++;
611 return RX_DROP_UNUSABLE;
612 }
613
Johannes Bergeb9fb5b2009-11-16 13:58:20 +0100614 if (!(status->flag & RX_FLAG_DECRYPTED)) {
Jouni Malinen765cb462009-01-08 13:32:01 +0200615 /* hardware didn't decrypt/verify MIC */
616 bip_aad(skb, aad);
Johannes Berg75396ae2011-07-06 22:00:35 +0200617 ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad,
Jouni Malinen765cb462009-01-08 13:32:01 +0200618 skb->data + 24, skb->len - 24, mic);
619 if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
620 key->u.aes_cmac.icverrors++;
621 return RX_DROP_UNUSABLE;
622 }
623 }
624
625 memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
626
627 /* Remove MMIE */
628 skb_trim(skb, skb->len - sizeof(*mmie));
629
630 return RX_CONTINUE;
631}