blob: 70778694877b4f59c66b2a162fb030a00f91f821 [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>
12#include <linux/slab.h>
13#include <linux/skbuff.h>
14#include <linux/compiler.h>
Harvey Harrisonf14df802008-07-02 11:05:35 -070015#include <linux/ieee80211.h>
16#include <asm/unaligned.h>
Jiri Bencf0706e82007-05-05 11:45:53 -070017#include <net/mac80211.h>
Johannes Bergeb063c12007-08-28 17:01:53 -040018
Jiri Bencf0706e82007-05-05 11:45:53 -070019#include "ieee80211_i.h"
20#include "michael.h"
21#include "tkip.h"
22#include "aes_ccm.h"
Jouni Malinen765cb462009-01-08 13:32:01 +020023#include "aes_cmac.h"
Jiri Bencf0706e82007-05-05 11:45:53 -070024#include "wpa.h"
25
Johannes Berg9ae54c82008-01-31 19:48:20 +010026ieee80211_tx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +010027ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
Jiri Bencf0706e82007-05-05 11:45:53 -070028{
Harvey Harrison8e8862b2008-07-02 11:05:35 -070029 u8 *data, *key, *mic, key_offset;
Jiri Bencf0706e82007-05-05 11:45:53 -070030 size_t data_len;
Harvey Harrison8e8862b2008-07-02 11:05:35 -070031 unsigned int hdrlen;
32 struct ieee80211_hdr *hdr;
Jiri Bencf0706e82007-05-05 11:45:53 -070033 struct sk_buff *skb = tx->skb;
34 int authenticator;
35 int wpa_test = 0;
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 Berg8f20fc22007-08-28 17:01:54 -040039 if (!tx->key || tx->key->conf.alg != ALG_TKIP || skb->len < 24 ||
Harvey Harrisonc34498b2008-07-02 16:30:52 -070040 !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
Johannes Berg11a843b2007-08-28 17:01:55 -040050 if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
Johannes Berg5cf121c2008-02-25 16:27:43 +010051 !(tx->flags & IEEE80211_TX_FRAGMENTED) &&
Johannes Berg7848ba72007-09-14 11:10:25 -040052 !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) &&
Jiri Bencf0706e82007-05-05 11:45:53 -070053 !wpa_test) {
Johannes Bergc6a1fa12008-10-07 12:04:32 +020054 /* hwaccel - with no need for preallocated room for MMIC */
Johannes Berg9ae54c82008-01-31 19:48:20 +010055 return TX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -070056 }
57
Johannes Berg23c07522008-05-29 10:38:53 +020058 tail = MICHAEL_MIC_LEN;
59 if (!(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
60 tail += TKIP_ICV_LEN;
61
62 if (WARN_ON(skb_tailroom(skb) < tail ||
63 skb_headroom(skb) < TKIP_IV_LEN))
64 return TX_DROP;
Jiri Bencf0706e82007-05-05 11:45:53 -070065
66#if 0
67 authenticator = fc & IEEE80211_FCTL_FROMDS; /* FIX */
68#else
69 authenticator = 1;
70#endif
Luis R. Rodriguezffd78912008-06-21 10:02:46 -040071 key_offset = authenticator ?
72 NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY :
73 NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY;
74 key = &tx->key->conf.key[key_offset];
Jiri Bencf0706e82007-05-05 11:45:53 -070075 mic = skb_put(skb, MICHAEL_MIC_LEN);
Harvey Harrison8e8862b2008-07-02 11:05:35 -070076 michael_mic(key, hdr, data, data_len, mic);
Jiri Bencf0706e82007-05-05 11:45:53 -070077
Johannes Berg9ae54c82008-01-31 19:48:20 +010078 return TX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -070079}
80
81
Johannes Berg9ae54c82008-01-31 19:48:20 +010082ieee80211_rx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +010083ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
Jiri Bencf0706e82007-05-05 11:45:53 -070084{
Harvey Harrison8e8862b2008-07-02 11:05:35 -070085 u8 *data, *key = NULL, key_offset;
Jiri Bencf0706e82007-05-05 11:45:53 -070086 size_t data_len;
Harvey Harrison8e8862b2008-07-02 11:05:35 -070087 unsigned int hdrlen;
88 struct ieee80211_hdr *hdr;
Jiri Bencf0706e82007-05-05 11:45:53 -070089 u8 mic[MICHAEL_MIC_LEN];
90 struct sk_buff *skb = rx->skb;
91 int authenticator = 1, wpa_test = 0;
92
Johannes Bergc6a1fa12008-10-07 12:04:32 +020093 /* No way to verify the MIC if the hardware stripped it */
Johannes Berg5cf121c2008-02-25 16:27:43 +010094 if (rx->status->flag & RX_FLAG_MMIC_STRIPPED)
Johannes Berg9ae54c82008-01-31 19:48:20 +010095 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -070096
Harvey Harrisonc34498b2008-07-02 16:30:52 -070097 hdr = (struct ieee80211_hdr *)skb->data;
Johannes Berg8f20fc22007-08-28 17:01:54 -040098 if (!rx->key || rx->key->conf.alg != ALG_TKIP ||
Harvey Harrisonc34498b2008-07-02 16:30:52 -070099 !ieee80211_has_protected(hdr->frame_control) ||
100 !ieee80211_is_data_present(hdr->frame_control))
Johannes Berg9ae54c82008-01-31 19:48:20 +0100101 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700102
Harvey Harrison8e8862b2008-07-02 11:05:35 -0700103 hdrlen = ieee80211_hdrlen(hdr->frame_control);
104 if (skb->len < hdrlen + MICHAEL_MIC_LEN)
Johannes Berge4c26ad2008-01-31 19:48:21 +0100105 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700106
Harvey Harrison8e8862b2008-07-02 11:05:35 -0700107 data = skb->data + hdrlen;
108 data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
Jiri Bencf0706e82007-05-05 11:45:53 -0700109
110#if 0
111 authenticator = fc & IEEE80211_FCTL_TODS; /* FIX */
112#else
113 authenticator = 1;
114#endif
Luis R. Rodriguezffd78912008-06-21 10:02:46 -0400115 key_offset = authenticator ?
116 NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY :
117 NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY;
118 key = &rx->key->conf.key[key_offset];
Harvey Harrison8e8862b2008-07-02 11:05:35 -0700119 michael_mic(key, hdr, data, data_len, mic);
Jiri Bencf0706e82007-05-05 11:45:53 -0700120 if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0 || wpa_test) {
Johannes Berg5cf121c2008-02-25 16:27:43 +0100121 if (!(rx->flags & IEEE80211_RX_RA_MATCH))
Johannes Berge4c26ad2008-01-31 19:48:21 +0100122 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700123
Jasper Bryant-Greenef698d852008-08-03 12:04:37 +1200124 mac80211_ev_michael_mic_failure(rx->sdata, rx->key->conf.keyidx,
Johannes Berge6d6e342009-07-01 21:26:47 +0200125 (void *) skb->data, NULL,
126 GFP_ATOMIC);
Johannes Berge4c26ad2008-01-31 19:48:21 +0100127 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700128 }
129
Jiri Bencf0706e82007-05-05 11:45:53 -0700130 /* remove Michael MIC from payload */
131 skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
132
Johannes Berg50741ae2007-09-26 15:19:45 +0200133 /* update IV in key information to be able to detect replays */
Harvey Harrisonb0f76b32008-05-14 16:26:19 -0700134 rx->key->u.tkip.rx[rx->queue].iv32 = rx->tkip_iv32;
135 rx->key->u.tkip.rx[rx->queue].iv16 = rx->tkip_iv16;
Johannes Berg50741ae2007-09-26 15:19:45 +0200136
Johannes Berg9ae54c82008-01-31 19:48:20 +0100137 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700138}
139
140
Johannes Berge039fa42008-05-15 12:55:29 +0200141static int tkip_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
Jiri Bencf0706e82007-05-05 11:45:53 -0700142{
143 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
144 struct ieee80211_key *key = tx->key;
Johannes Berge039fa42008-05-15 12:55:29 +0200145 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
Harvey Harrisond5184ca2008-06-11 14:21:58 -0700146 unsigned int hdrlen;
147 int len, tail;
Jiri Bencf0706e82007-05-05 11:45:53 -0700148 u8 *pos;
149
Johannes Berge039fa42008-05-15 12:55:29 +0200150 if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
151 !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV)) {
152 /* hwaccel - with no need for preallocated room for IV/ICV */
153 info->control.hw_key = &tx->key->conf;
Johannes Berg23c07522008-05-29 10:38:53 +0200154 return 0;
Johannes Berge039fa42008-05-15 12:55:29 +0200155 }
156
Harvey Harrisond5184ca2008-06-11 14:21:58 -0700157 hdrlen = ieee80211_hdrlen(hdr->frame_control);
Jiri Bencf0706e82007-05-05 11:45:53 -0700158 len = skb->len - hdrlen;
159
Johannes Berg11a843b2007-08-28 17:01:55 -0400160 if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
Johannes Berg23c07522008-05-29 10:38:53 +0200161 tail = 0;
Johannes Berg11a843b2007-08-28 17:01:55 -0400162 else
Johannes Berg23c07522008-05-29 10:38:53 +0200163 tail = TKIP_ICV_LEN;
Johannes Berg8f20fc22007-08-28 17:01:54 -0400164
Johannes Berg23c07522008-05-29 10:38:53 +0200165 if (WARN_ON(skb_tailroom(skb) < tail ||
166 skb_headroom(skb) < TKIP_IV_LEN))
167 return -1;
Jiri Bencf0706e82007-05-05 11:45:53 -0700168
169 pos = skb_push(skb, TKIP_IV_LEN);
170 memmove(pos, pos + TKIP_IV_LEN, hdrlen);
171 pos += hdrlen;
172
173 /* Increase IV for the frame */
Harvey Harrisonb0f76b32008-05-14 16:26:19 -0700174 key->u.tkip.tx.iv16++;
175 if (key->u.tkip.tx.iv16 == 0)
176 key->u.tkip.tx.iv32++;
Jiri Bencf0706e82007-05-05 11:45:53 -0700177
Johannes Berg11a843b2007-08-28 17:01:55 -0400178 if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
Jiri Bencf0706e82007-05-05 11:45:53 -0700179 /* hwaccel - with preallocated room for IV */
Harvey Harrisonc8012422008-06-11 14:22:00 -0700180 ieee80211_tkip_add_iv(pos, key, key->u.tkip.tx.iv16);
Jiri Bencf0706e82007-05-05 11:45:53 -0700181
Johannes Berge039fa42008-05-15 12:55:29 +0200182 info->control.hw_key = &tx->key->conf;
Jiri Bencf0706e82007-05-05 11:45:53 -0700183 return 0;
184 }
185
186 /* Add room for ICV */
187 skb_put(skb, TKIP_ICV_LEN);
188
189 hdr = (struct ieee80211_hdr *) skb->data;
190 ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,
191 key, pos, len, hdr->addr2);
192 return 0;
193}
194
195
Johannes Berg9ae54c82008-01-31 19:48:20 +0100196ieee80211_tx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100197ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
Jiri Bencf0706e82007-05-05 11:45:53 -0700198{
Jiri Bencf0706e82007-05-05 11:45:53 -0700199 struct sk_buff *skb = tx->skb;
Jiri Bencf0706e82007-05-05 11:45:53 -0700200
Johannes Berg5cf121c2008-02-25 16:27:43 +0100201 ieee80211_tx_set_protected(tx);
Jiri Bencf0706e82007-05-05 11:45:53 -0700202
Johannes Berg2de8e0d2009-03-23 17:28:35 +0100203 do {
204 if (tkip_encrypt_skb(tx, skb) < 0)
205 return TX_DROP;
206 } while ((skb = skb->next));
Jiri Bencf0706e82007-05-05 11:45:53 -0700207
Johannes Berg9ae54c82008-01-31 19:48:20 +0100208 return TX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700209}
210
211
Johannes Berg9ae54c82008-01-31 19:48:20 +0100212ieee80211_rx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100213ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
Jiri Bencf0706e82007-05-05 11:45:53 -0700214{
215 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;
Jiri Bencf0706e82007-05-05 11:45:53 -0700216 int hdrlen, res, hwaccel = 0, wpa_test = 0;
217 struct ieee80211_key *key = rx->key;
218 struct sk_buff *skb = rx->skb;
219
Harvey Harrisond5184ca2008-06-11 14:21:58 -0700220 hdrlen = ieee80211_hdrlen(hdr->frame_control);
Jiri Bencf0706e82007-05-05 11:45:53 -0700221
Harvey Harrisonc34498b2008-07-02 16:30:52 -0700222 if (!ieee80211_is_data(hdr->frame_control))
Johannes Berg9ae54c82008-01-31 19:48:20 +0100223 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700224
225 if (!rx->sta || skb->len - hdrlen < 12)
Johannes Berge4c26ad2008-01-31 19:48:21 +0100226 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700227
Johannes Berg5cf121c2008-02-25 16:27:43 +0100228 if (rx->status->flag & RX_FLAG_DECRYPTED) {
229 if (rx->status->flag & RX_FLAG_IV_STRIPPED) {
Johannes Berg7848ba72007-09-14 11:10:25 -0400230 /*
231 * Hardware took care of all processing, including
232 * replay protection, and stripped the ICV/IV so
233 * we cannot do any checks here.
234 */
Johannes Berg9ae54c82008-01-31 19:48:20 +0100235 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700236 }
237
238 /* let TKIP code verify IV, but skip decryption */
239 hwaccel = 1;
240 }
241
242 res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,
243 key, skb->data + hdrlen,
Johannes Berg17741cd2008-09-11 00:02:02 +0200244 skb->len - hdrlen, rx->sta->sta.addr,
Emmanuel Grumbach9ae4fda2008-03-20 15:06:42 +0200245 hdr->addr1, hwaccel, rx->queue,
Johannes Berg5cf121c2008-02-25 16:27:43 +0100246 &rx->tkip_iv32,
247 &rx->tkip_iv16);
Johannes Bergf4ea83d2008-06-30 15:10:46 +0200248 if (res != TKIP_DECRYPT_OK || wpa_test)
Johannes Berge4c26ad2008-01-31 19:48:21 +0100249 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700250
251 /* Trim ICV */
252 skb_trim(skb, skb->len - TKIP_ICV_LEN);
253
254 /* Remove IV */
255 memmove(skb->data + TKIP_IV_LEN, skb->data, hdrlen);
256 skb_pull(skb, TKIP_IV_LEN);
257
Johannes Berg9ae54c82008-01-31 19:48:20 +0100258 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700259}
260
261
Harvey Harrisonfeccb462008-07-02 16:30:52 -0700262static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *scratch,
Jiri Bencf0706e82007-05-05 11:45:53 -0700263 int encrypted)
264{
Harvey Harrisonf14df802008-07-02 11:05:35 -0700265 __le16 mask_fc;
Jouni Malinenfb733332009-01-08 13:32:00 +0200266 int a4_included, mgmt;
Harvey Harrisonf14df802008-07-02 11:05:35 -0700267 u8 qos_tid;
Harvey Harrisonfeccb462008-07-02 16:30:52 -0700268 u8 *b_0, *aad;
Harvey Harrisonf14df802008-07-02 11:05:35 -0700269 u16 data_len, len_a;
270 unsigned int hdrlen;
271 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
Jiri Bencf0706e82007-05-05 11:45:53 -0700272
Harvey Harrisonfeccb462008-07-02 16:30:52 -0700273 b_0 = scratch + 3 * AES_BLOCK_LEN;
274 aad = scratch + 4 * AES_BLOCK_LEN;
275
Harvey Harrisonf14df802008-07-02 11:05:35 -0700276 /*
Jouni Malinenfb733332009-01-08 13:32:00 +0200277 * Mask FC: zero subtype b4 b5 b6 (if not mgmt)
Harvey Harrisonf14df802008-07-02 11:05:35 -0700278 * Retry, PwrMgt, MoreData; set Protected
279 */
Jouni Malinenfb733332009-01-08 13:32:00 +0200280 mgmt = ieee80211_is_mgmt(hdr->frame_control);
Harvey Harrisonf14df802008-07-02 11:05:35 -0700281 mask_fc = hdr->frame_control;
Jouni Malinenfb733332009-01-08 13:32:00 +0200282 mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
Harvey Harrisonf14df802008-07-02 11:05:35 -0700283 IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
Jouni Malinenfb733332009-01-08 13:32:00 +0200284 if (!mgmt)
285 mask_fc &= ~cpu_to_le16(0x0070);
Harvey Harrisonf14df802008-07-02 11:05:35 -0700286 mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
Jiri Bencf0706e82007-05-05 11:45:53 -0700287
Harvey Harrisonf14df802008-07-02 11:05:35 -0700288 hdrlen = ieee80211_hdrlen(hdr->frame_control);
289 len_a = hdrlen - 2;
290 a4_included = ieee80211_has_a4(hdr->frame_control);
291
292 if (ieee80211_is_data_qos(hdr->frame_control))
293 qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
294 else
295 qos_tid = 0;
296
297 data_len = skb->len - hdrlen - CCMP_HDR_LEN;
298 if (encrypted)
299 data_len -= CCMP_MIC_LEN;
300
Jiri Bencf0706e82007-05-05 11:45:53 -0700301 /* First block, b_0 */
Jiri Bencf0706e82007-05-05 11:45:53 -0700302 b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */
Jouni Malinenfb733332009-01-08 13:32:00 +0200303 /* Nonce: Nonce Flags | A2 | PN
304 * Nonce Flags: Priority (b0..b3) | Management (b4) | Reserved (b5..b7)
305 */
306 b_0[1] = qos_tid | (mgmt << 4);
Harvey Harrison73e1f7c2008-07-02 11:05:34 -0700307 memcpy(&b_0[2], hdr->addr2, ETH_ALEN);
Jiri Bencf0706e82007-05-05 11:45:53 -0700308 memcpy(&b_0[8], pn, CCMP_PN_LEN);
309 /* l(m) */
Harvey Harrisonf14df802008-07-02 11:05:35 -0700310 put_unaligned_be16(data_len, &b_0[14]);
Jiri Bencf0706e82007-05-05 11:45:53 -0700311
312 /* AAD (extra authenticate-only data) / masked 802.11 header
313 * FC | A1 | A2 | A3 | SC | [A4] | [QC] */
Harvey Harrisonf14df802008-07-02 11:05:35 -0700314 put_unaligned_be16(len_a, &aad[0]);
315 put_unaligned(mask_fc, (__le16 *)&aad[2]);
Harvey Harrison73e1f7c2008-07-02 11:05:34 -0700316 memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
Jiri Bencf0706e82007-05-05 11:45:53 -0700317
318 /* Mask Seq#, leave Frag# */
319 aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;
320 aad[23] = 0;
Harvey Harrisonf14df802008-07-02 11:05:35 -0700321
Jiri Bencf0706e82007-05-05 11:45:53 -0700322 if (a4_included) {
Harvey Harrison73e1f7c2008-07-02 11:05:34 -0700323 memcpy(&aad[24], hdr->addr4, ETH_ALEN);
Harvey Harrisonf14df802008-07-02 11:05:35 -0700324 aad[30] = qos_tid;
Jiri Bencf0706e82007-05-05 11:45:53 -0700325 aad[31] = 0;
Harvey Harrisonf14df802008-07-02 11:05:35 -0700326 } else {
Harvey Harrison73e1f7c2008-07-02 11:05:34 -0700327 memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
Harvey Harrisonf14df802008-07-02 11:05:35 -0700328 aad[24] = qos_tid;
Jiri Bencf0706e82007-05-05 11:45:53 -0700329 }
330}
331
332
333static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)
334{
335 hdr[0] = pn[5];
336 hdr[1] = pn[4];
337 hdr[2] = 0;
338 hdr[3] = 0x20 | (key_id << 6);
339 hdr[4] = pn[3];
340 hdr[5] = pn[2];
341 hdr[6] = pn[1];
342 hdr[7] = pn[0];
343}
344
345
Johannes Bergc6a1fa12008-10-07 12:04:32 +0200346static inline void ccmp_hdr2pn(u8 *pn, u8 *hdr)
Jiri Bencf0706e82007-05-05 11:45:53 -0700347{
348 pn[0] = hdr[7];
349 pn[1] = hdr[6];
350 pn[2] = hdr[5];
351 pn[3] = hdr[4];
352 pn[4] = hdr[1];
353 pn[5] = hdr[0];
Jiri Bencf0706e82007-05-05 11:45:53 -0700354}
355
356
Johannes Berge039fa42008-05-15 12:55:29 +0200357static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
Jiri Bencf0706e82007-05-05 11:45:53 -0700358{
359 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
360 struct ieee80211_key *key = tx->key;
Johannes Berge039fa42008-05-15 12:55:29 +0200361 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
Johannes Berg23c07522008-05-29 10:38:53 +0200362 int hdrlen, len, tail;
Harvey Harrisonfeccb462008-07-02 16:30:52 -0700363 u8 *pos, *pn;
Jiri Bencf0706e82007-05-05 11:45:53 -0700364 int i;
Jouni Malinen1f7d77a2009-01-08 13:32:10 +0200365 bool skip_hw;
366
367 skip_hw = (tx->key->conf.flags & IEEE80211_KEY_FLAG_SW_MGMT) &&
368 ieee80211_is_mgmt(hdr->frame_control);
Jiri Bencf0706e82007-05-05 11:45:53 -0700369
Johannes Berge039fa42008-05-15 12:55:29 +0200370 if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
Jouni Malinen1f7d77a2009-01-08 13:32:10 +0200371 !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
372 !skip_hw) {
Johannes Bergc6a1fa12008-10-07 12:04:32 +0200373 /* hwaccel - with no need for preallocated room for CCMP
Johannes Berge039fa42008-05-15 12:55:29 +0200374 * header or MIC fields */
375 info->control.hw_key = &tx->key->conf;
Johannes Berg23c07522008-05-29 10:38:53 +0200376 return 0;
Johannes Berge039fa42008-05-15 12:55:29 +0200377 }
378
Harvey Harrisond5184ca2008-06-11 14:21:58 -0700379 hdrlen = ieee80211_hdrlen(hdr->frame_control);
Jiri Bencf0706e82007-05-05 11:45:53 -0700380 len = skb->len - hdrlen;
381
Johannes Berg11a843b2007-08-28 17:01:55 -0400382 if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
Johannes Berg23c07522008-05-29 10:38:53 +0200383 tail = 0;
Johannes Berg11a843b2007-08-28 17:01:55 -0400384 else
Johannes Berg23c07522008-05-29 10:38:53 +0200385 tail = CCMP_MIC_LEN;
Jiri Bencf0706e82007-05-05 11:45:53 -0700386
Johannes Berg23c07522008-05-29 10:38:53 +0200387 if (WARN_ON(skb_tailroom(skb) < tail ||
388 skb_headroom(skb) < CCMP_HDR_LEN))
389 return -1;
Jiri Bencf0706e82007-05-05 11:45:53 -0700390
391 pos = skb_push(skb, CCMP_HDR_LEN);
392 memmove(pos, pos + CCMP_HDR_LEN, hdrlen);
393 hdr = (struct ieee80211_hdr *) pos;
394 pos += hdrlen;
395
396 /* PN = PN + 1 */
397 pn = key->u.ccmp.tx_pn;
398
399 for (i = CCMP_PN_LEN - 1; i >= 0; i--) {
400 pn[i]++;
401 if (pn[i])
402 break;
403 }
404
Johannes Berg8f20fc22007-08-28 17:01:54 -0400405 ccmp_pn2hdr(pos, pn, key->conf.keyidx);
Jiri Bencf0706e82007-05-05 11:45:53 -0700406
Jouni Malinen1f7d77a2009-01-08 13:32:10 +0200407 if ((key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) && !skip_hw) {
Jiri Bencf0706e82007-05-05 11:45:53 -0700408 /* hwaccel - with preallocated room for CCMP header */
Johannes Berge039fa42008-05-15 12:55:29 +0200409 info->control.hw_key = &tx->key->conf;
Jiri Bencf0706e82007-05-05 11:45:53 -0700410 return 0;
411 }
412
413 pos += CCMP_HDR_LEN;
Harvey Harrisonfeccb462008-07-02 16:30:52 -0700414 ccmp_special_blocks(skb, pn, key->u.ccmp.tx_crypto_buf, 0);
415 ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, key->u.ccmp.tx_crypto_buf, pos, len,
Jiri Bencf0706e82007-05-05 11:45:53 -0700416 pos, skb_put(skb, CCMP_MIC_LEN));
417
418 return 0;
419}
420
421
Johannes Berg9ae54c82008-01-31 19:48:20 +0100422ieee80211_tx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100423ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx)
Jiri Bencf0706e82007-05-05 11:45:53 -0700424{
Jiri Bencf0706e82007-05-05 11:45:53 -0700425 struct sk_buff *skb = tx->skb;
Jiri Bencf0706e82007-05-05 11:45:53 -0700426
Johannes Berg5cf121c2008-02-25 16:27:43 +0100427 ieee80211_tx_set_protected(tx);
Jiri Bencf0706e82007-05-05 11:45:53 -0700428
Johannes Berg2de8e0d2009-03-23 17:28:35 +0100429 do {
430 if (ccmp_encrypt_skb(tx, skb) < 0)
431 return TX_DROP;
432 } while ((skb = skb->next));
Jiri Bencf0706e82007-05-05 11:45:53 -0700433
Johannes Berg9ae54c82008-01-31 19:48:20 +0100434 return TX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700435}
436
437
Johannes Berg9ae54c82008-01-31 19:48:20 +0100438ieee80211_rx_result
Johannes Berg5cf121c2008-02-25 16:27:43 +0100439ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx)
Jiri Bencf0706e82007-05-05 11:45:53 -0700440{
Harvey Harrisonc34498b2008-07-02 16:30:52 -0700441 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
Jiri Bencf0706e82007-05-05 11:45:53 -0700442 int hdrlen;
443 struct ieee80211_key *key = rx->key;
444 struct sk_buff *skb = rx->skb;
445 u8 pn[CCMP_PN_LEN];
446 int data_len;
447
Harvey Harrisond5184ca2008-06-11 14:21:58 -0700448 hdrlen = ieee80211_hdrlen(hdr->frame_control);
Jiri Bencf0706e82007-05-05 11:45:53 -0700449
Jouni Malinenfb733332009-01-08 13:32:00 +0200450 if (!ieee80211_is_data(hdr->frame_control) &&
451 !ieee80211_is_robust_mgmt_frame(hdr))
Johannes Berg9ae54c82008-01-31 19:48:20 +0100452 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700453
454 data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN;
455 if (!rx->sta || data_len < 0)
Johannes Berge4c26ad2008-01-31 19:48:21 +0100456 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700457
Johannes Berg5cf121c2008-02-25 16:27:43 +0100458 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
459 (rx->status->flag & RX_FLAG_IV_STRIPPED))
Johannes Berg9ae54c82008-01-31 19:48:20 +0100460 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700461
Johannes Bergc6a1fa12008-10-07 12:04:32 +0200462 ccmp_hdr2pn(pn, skb->data + hdrlen);
Jiri Bencf0706e82007-05-05 11:45:53 -0700463
Johannes Berg5cf121c2008-02-25 16:27:43 +0100464 if (memcmp(pn, key->u.ccmp.rx_pn[rx->queue], CCMP_PN_LEN) <= 0) {
Jiri Bencf0706e82007-05-05 11:45:53 -0700465 key->u.ccmp.replays++;
Johannes Berge4c26ad2008-01-31 19:48:21 +0100466 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700467 }
468
Johannes Berg5cf121c2008-02-25 16:27:43 +0100469 if (!(rx->status->flag & RX_FLAG_DECRYPTED)) {
Johannes Berg7848ba72007-09-14 11:10:25 -0400470 /* hardware didn't decrypt/verify MIC */
Harvey Harrisonfeccb462008-07-02 16:30:52 -0700471 ccmp_special_blocks(skb, pn, key->u.ccmp.rx_crypto_buf, 1);
Jiri Bencf0706e82007-05-05 11:45:53 -0700472
473 if (ieee80211_aes_ccm_decrypt(
Harvey Harrisonfeccb462008-07-02 16:30:52 -0700474 key->u.ccmp.tfm, key->u.ccmp.rx_crypto_buf,
Jiri Bencf0706e82007-05-05 11:45:53 -0700475 skb->data + hdrlen + CCMP_HDR_LEN, data_len,
476 skb->data + skb->len - CCMP_MIC_LEN,
Johannes Bergc6a1fa12008-10-07 12:04:32 +0200477 skb->data + hdrlen + CCMP_HDR_LEN))
Johannes Berge4c26ad2008-01-31 19:48:21 +0100478 return RX_DROP_UNUSABLE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700479 }
480
Johannes Berg5cf121c2008-02-25 16:27:43 +0100481 memcpy(key->u.ccmp.rx_pn[rx->queue], pn, CCMP_PN_LEN);
Jiri Bencf0706e82007-05-05 11:45:53 -0700482
483 /* Remove CCMP header and MIC */
484 skb_trim(skb, skb->len - CCMP_MIC_LEN);
485 memmove(skb->data + CCMP_HDR_LEN, skb->data, hdrlen);
486 skb_pull(skb, CCMP_HDR_LEN);
487
Johannes Berg9ae54c82008-01-31 19:48:20 +0100488 return RX_CONTINUE;
Jiri Bencf0706e82007-05-05 11:45:53 -0700489}
Jouni Malinen765cb462009-01-08 13:32:01 +0200490
491
492static void bip_aad(struct sk_buff *skb, u8 *aad)
493{
494 /* BIP AAD: FC(masked) || A1 || A2 || A3 */
495
496 /* FC type/subtype */
497 aad[0] = skb->data[0];
498 /* Mask FC Retry, PwrMgt, MoreData flags to zero */
499 aad[1] = skb->data[1] & ~(BIT(4) | BIT(5) | BIT(6));
500 /* A1 || A2 || A3 */
501 memcpy(aad + 2, skb->data + 4, 3 * ETH_ALEN);
502}
503
504
505static inline void bip_ipn_swap(u8 *d, const u8 *s)
506{
507 *d++ = s[5];
508 *d++ = s[4];
509 *d++ = s[3];
510 *d++ = s[2];
511 *d++ = s[1];
512 *d = s[0];
513}
514
515
516ieee80211_tx_result
517ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx)
518{
519 struct sk_buff *skb = tx->skb;
520 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
521 struct ieee80211_key *key = tx->key;
522 struct ieee80211_mmie *mmie;
523 u8 *pn, aad[20];
524 int i;
525
526 if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
527 /* hwaccel */
528 info->control.hw_key = &tx->key->conf;
529 return 0;
530 }
531
532 if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie)))
533 return TX_DROP;
534
535 mmie = (struct ieee80211_mmie *) skb_put(skb, sizeof(*mmie));
536 mmie->element_id = WLAN_EID_MMIE;
537 mmie->length = sizeof(*mmie) - 2;
538 mmie->key_id = cpu_to_le16(key->conf.keyidx);
539
540 /* PN = PN + 1 */
541 pn = key->u.aes_cmac.tx_pn;
542
543 for (i = sizeof(key->u.aes_cmac.tx_pn) - 1; i >= 0; i--) {
544 pn[i]++;
545 if (pn[i])
546 break;
547 }
548 bip_ipn_swap(mmie->sequence_number, pn);
549
550 bip_aad(skb, aad);
551
552 /*
553 * MIC = AES-128-CMAC(IGTK, AAD || Management Frame Body || MMIE, 64)
554 */
555 ieee80211_aes_cmac(key->u.aes_cmac.tfm, key->u.aes_cmac.tx_crypto_buf,
556 aad, skb->data + 24, skb->len - 24, mmie->mic);
557
558 return TX_CONTINUE;
559}
560
561
562ieee80211_rx_result
563ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
564{
565 struct sk_buff *skb = rx->skb;
566 struct ieee80211_key *key = rx->key;
567 struct ieee80211_mmie *mmie;
568 u8 aad[20], mic[8], ipn[6];
569 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
570
571 if (!ieee80211_is_mgmt(hdr->frame_control))
572 return RX_CONTINUE;
573
574 if ((rx->status->flag & RX_FLAG_DECRYPTED) &&
575 (rx->status->flag & RX_FLAG_IV_STRIPPED))
576 return RX_CONTINUE;
577
578 if (skb->len < 24 + sizeof(*mmie))
579 return RX_DROP_UNUSABLE;
580
581 mmie = (struct ieee80211_mmie *)
582 (skb->data + skb->len - sizeof(*mmie));
583 if (mmie->element_id != WLAN_EID_MMIE ||
584 mmie->length != sizeof(*mmie) - 2)
585 return RX_DROP_UNUSABLE; /* Invalid MMIE */
586
587 bip_ipn_swap(ipn, mmie->sequence_number);
588
589 if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
590 key->u.aes_cmac.replays++;
591 return RX_DROP_UNUSABLE;
592 }
593
594 if (!(rx->status->flag & RX_FLAG_DECRYPTED)) {
595 /* hardware didn't decrypt/verify MIC */
596 bip_aad(skb, aad);
597 ieee80211_aes_cmac(key->u.aes_cmac.tfm,
598 key->u.aes_cmac.rx_crypto_buf, aad,
599 skb->data + 24, skb->len - 24, mic);
600 if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) {
601 key->u.aes_cmac.icverrors++;
602 return RX_DROP_UNUSABLE;
603 }
604 }
605
606 memcpy(key->u.aes_cmac.rx_pn, ipn, 6);
607
608 /* Remove MMIE */
609 skb_trim(skb, skb->len - sizeof(*mmie));
610
611 return RX_CONTINUE;
612}