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Commit | Line | Data |
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2bb057d0 | 1 | /* |
9c9a0d14 | 2 | Copyright (C) 2004 - 2009 Ivo van Doorn <IvDoorn@gmail.com> |
2bb057d0 ID |
3 | <http://rt2x00.serialmonkey.com> |
4 | ||
5 | This program is free software; you can redistribute it and/or modify | |
6 | it under the terms of the GNU General Public License as published by | |
7 | the Free Software Foundation; either version 2 of the License, or | |
8 | (at your option) any later version. | |
9 | ||
10 | This program is distributed in the hope that it will be useful, | |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | GNU General Public License for more details. | |
14 | ||
15 | You should have received a copy of the GNU General Public License | |
16 | along with this program; if not, write to the | |
17 | Free Software Foundation, Inc., | |
18 | 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
19 | */ | |
20 | ||
21 | /* | |
22 | Module: rt2x00lib | |
23 | Abstract: rt2x00 crypto specific routines. | |
24 | */ | |
25 | ||
26 | #include <linux/kernel.h> | |
27 | #include <linux/module.h> | |
28 | ||
29 | #include "rt2x00.h" | |
30 | #include "rt2x00lib.h" | |
31 | ||
32 | enum cipher rt2x00crypto_key_to_cipher(struct ieee80211_key_conf *key) | |
33 | { | |
34 | switch (key->alg) { | |
35 | case ALG_WEP: | |
e31a16d6 | 36 | if (key->keylen == WLAN_KEY_LEN_WEP40) |
2bb057d0 ID |
37 | return CIPHER_WEP64; |
38 | else | |
39 | return CIPHER_WEP128; | |
40 | case ALG_TKIP: | |
41 | return CIPHER_TKIP; | |
42 | case ALG_CCMP: | |
43 | return CIPHER_AES; | |
44 | default: | |
45 | return CIPHER_NONE; | |
46 | } | |
47 | } | |
48 | ||
9c3444d3 ID |
49 | void rt2x00crypto_create_tx_descriptor(struct queue_entry *entry, |
50 | struct txentry_desc *txdesc) | |
51 | { | |
7b40982e | 52 | struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev; |
9c3444d3 ID |
53 | struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(entry->skb); |
54 | struct ieee80211_key_conf *hw_key = tx_info->control.hw_key; | |
55 | ||
18ad01c4 | 56 | if (!test_bit(CONFIG_SUPPORT_HW_CRYPTO, &rt2x00dev->flags) || !hw_key) |
7b40982e ID |
57 | return; |
58 | ||
9c3444d3 ID |
59 | __set_bit(ENTRY_TXD_ENCRYPT, &txdesc->flags); |
60 | ||
61 | txdesc->cipher = rt2x00crypto_key_to_cipher(hw_key); | |
62 | ||
63 | if (hw_key->flags & IEEE80211_KEY_FLAG_PAIRWISE) | |
64 | __set_bit(ENTRY_TXD_ENCRYPT_PAIRWISE, &txdesc->flags); | |
65 | ||
66 | txdesc->key_idx = hw_key->hw_key_idx; | |
9f166171 | 67 | txdesc->iv_offset = txdesc->header_length; |
9eb4e21e | 68 | txdesc->iv_len = hw_key->iv_len; |
9c3444d3 ID |
69 | |
70 | if (!(hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV)) | |
71 | __set_bit(ENTRY_TXD_ENCRYPT_IV, &txdesc->flags); | |
72 | ||
73 | if (!(hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) | |
74 | __set_bit(ENTRY_TXD_ENCRYPT_MMIC, &txdesc->flags); | |
75 | } | |
76 | ||
7b40982e ID |
77 | unsigned int rt2x00crypto_tx_overhead(struct rt2x00_dev *rt2x00dev, |
78 | struct sk_buff *skb) | |
2bb057d0 | 79 | { |
7b40982e | 80 | struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb); |
2bb057d0 ID |
81 | struct ieee80211_key_conf *key = tx_info->control.hw_key; |
82 | unsigned int overhead = 0; | |
83 | ||
18ad01c4 | 84 | if (!test_bit(CONFIG_SUPPORT_HW_CRYPTO, &rt2x00dev->flags) || !key) |
7b40982e ID |
85 | return overhead; |
86 | ||
2bb057d0 ID |
87 | /* |
88 | * Extend frame length to include IV/EIV/ICV/MMIC, | |
89 | * note that these lengths should only be added when | |
90 | * mac80211 does not generate it. | |
91 | */ | |
76708dee | 92 | overhead += key->icv_len; |
2bb057d0 ID |
93 | |
94 | if (!(key->flags & IEEE80211_KEY_FLAG_GENERATE_IV)) | |
76708dee | 95 | overhead += key->iv_len; |
2bb057d0 ID |
96 | |
97 | if (!(key->flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) { | |
98 | if (key->alg == ALG_TKIP) | |
99 | overhead += 8; | |
100 | } | |
101 | ||
102 | return overhead; | |
103 | } | |
104 | ||
9eb4e21e | 105 | void rt2x00crypto_tx_copy_iv(struct sk_buff *skb, struct txentry_desc *txdesc) |
dddfb478 ID |
106 | { |
107 | struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb); | |
dddfb478 | 108 | |
9eb4e21e | 109 | if (unlikely(!txdesc->iv_len)) |
dddfb478 ID |
110 | return; |
111 | ||
112 | /* Copy IV/EIV data */ | |
9eb4e21e | 113 | memcpy(skbdesc->iv, skb->data + txdesc->iv_offset, txdesc->iv_len); |
dddfb478 ID |
114 | } |
115 | ||
9eb4e21e | 116 | void rt2x00crypto_tx_remove_iv(struct sk_buff *skb, struct txentry_desc *txdesc) |
2bb057d0 ID |
117 | { |
118 | struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb); | |
2bb057d0 | 119 | |
9eb4e21e | 120 | if (unlikely(!txdesc->iv_len)) |
2bb057d0 ID |
121 | return; |
122 | ||
123 | /* Copy IV/EIV data */ | |
9eb4e21e | 124 | memcpy(skbdesc->iv, skb->data + txdesc->iv_offset, txdesc->iv_len); |
2bb057d0 ID |
125 | |
126 | /* Move ieee80211 header */ | |
9eb4e21e | 127 | memmove(skb->data + txdesc->iv_len, skb->data, txdesc->iv_offset); |
2bb057d0 ID |
128 | |
129 | /* Pull buffer to correct size */ | |
9eb4e21e | 130 | skb_pull(skb, txdesc->iv_len); |
2bb057d0 | 131 | |
49513481 | 132 | /* IV/EIV data has officially been stripped */ |
9f166171 | 133 | skbdesc->flags |= SKBDESC_IV_STRIPPED; |
2bb057d0 ID |
134 | } |
135 | ||
9f166171 | 136 | void rt2x00crypto_tx_insert_iv(struct sk_buff *skb, unsigned int header_length) |
2bb057d0 ID |
137 | { |
138 | struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb); | |
2bb057d0 | 139 | const unsigned int iv_len = |
1ce9cdac | 140 | ((!!(skbdesc->iv[0])) * 4) + ((!!(skbdesc->iv[1])) * 4); |
2bb057d0 | 141 | |
9f166171 | 142 | if (!(skbdesc->flags & SKBDESC_IV_STRIPPED)) |
2bb057d0 ID |
143 | return; |
144 | ||
145 | skb_push(skb, iv_len); | |
146 | ||
147 | /* Move ieee80211 header */ | |
148 | memmove(skb->data, skb->data + iv_len, header_length); | |
149 | ||
150 | /* Copy IV/EIV data */ | |
1ce9cdac | 151 | memcpy(skb->data + header_length, skbdesc->iv, iv_len); |
2bb057d0 ID |
152 | |
153 | /* IV/EIV data has returned into the frame */ | |
9f166171 | 154 | skbdesc->flags &= ~SKBDESC_IV_STRIPPED; |
2bb057d0 ID |
155 | } |
156 | ||
daee6c09 | 157 | void rt2x00crypto_rx_insert_iv(struct sk_buff *skb, |
2bb057d0 ID |
158 | unsigned int header_length, |
159 | struct rxdone_entry_desc *rxdesc) | |
160 | { | |
161 | unsigned int payload_len = rxdesc->size - header_length; | |
9f166171 | 162 | unsigned int align = ALIGN_SIZE(skb, header_length); |
2bb057d0 ID |
163 | unsigned int iv_len; |
164 | unsigned int icv_len; | |
165 | unsigned int transfer = 0; | |
166 | ||
167 | /* | |
168 | * WEP64/WEP128: Provides IV & ICV | |
169 | * TKIP: Provides IV/EIV & ICV | |
170 | * AES: Provies IV/EIV & ICV | |
171 | */ | |
172 | switch (rxdesc->cipher) { | |
173 | case CIPHER_WEP64: | |
174 | case CIPHER_WEP128: | |
175 | iv_len = 4; | |
176 | icv_len = 4; | |
177 | break; | |
178 | case CIPHER_TKIP: | |
179 | iv_len = 8; | |
180 | icv_len = 4; | |
181 | break; | |
182 | case CIPHER_AES: | |
183 | iv_len = 8; | |
184 | icv_len = 8; | |
185 | break; | |
186 | default: | |
187 | /* Unsupport type */ | |
188 | return; | |
189 | } | |
190 | ||
191 | /* | |
9f166171 ID |
192 | * Make room for new data. There are 2 possibilities |
193 | * either the alignment is already present between | |
194 | * the 802.11 header and payload. In that case we | |
195 | * we have to move the header less then the iv_len | |
196 | * since we can use the already available l2pad bytes | |
197 | * for the iv data. | |
198 | * When the alignment must be added manually we must | |
199 | * move the header more then iv_len since we must | |
200 | * make room for the payload move as well. | |
2bb057d0 | 201 | */ |
daee6c09 | 202 | if (rxdesc->dev_flags & RXDONE_L2PAD) { |
9f166171 ID |
203 | skb_push(skb, iv_len - align); |
204 | skb_put(skb, icv_len); | |
2bb057d0 | 205 | |
9f166171 ID |
206 | /* Move ieee80211 header */ |
207 | memmove(skb->data + transfer, | |
208 | skb->data + transfer + (iv_len - align), | |
209 | header_length); | |
210 | transfer += header_length; | |
211 | } else { | |
212 | skb_push(skb, iv_len + align); | |
213 | if (align < icv_len) | |
214 | skb_put(skb, icv_len - align); | |
215 | else if (align > icv_len) | |
216 | skb_trim(skb, rxdesc->size + iv_len + icv_len); | |
217 | ||
218 | /* Move ieee80211 header */ | |
219 | memmove(skb->data + transfer, | |
220 | skb->data + transfer + iv_len + align, | |
221 | header_length); | |
222 | transfer += header_length; | |
223 | } | |
2bb057d0 | 224 | |
1ce9cdac ID |
225 | /* Copy IV/EIV data */ |
226 | memcpy(skb->data + transfer, rxdesc->iv, iv_len); | |
227 | transfer += iv_len; | |
2bb057d0 | 228 | |
9f166171 ID |
229 | /* |
230 | * Move payload for alignment purposes. Note that | |
231 | * this is only needed when no l2 padding is present. | |
232 | */ | |
daee6c09 | 233 | if (!(rxdesc->dev_flags & RXDONE_L2PAD)) { |
2bb057d0 ID |
234 | memmove(skb->data + transfer, |
235 | skb->data + transfer + align, | |
236 | payload_len); | |
237 | } | |
238 | ||
239 | /* | |
240 | * NOTE: Always count the payload as transfered, | |
241 | * even when alignment was set to zero. This is required | |
242 | * for determining the correct offset for the ICV data. | |
243 | */ | |
244 | transfer += payload_len; | |
245 | ||
1ce9cdac ID |
246 | /* |
247 | * Copy ICV data | |
248 | * AES appends 8 bytes, we can't fill the upper | |
249 | * 4 bytes, but mac80211 doesn't care about what | |
250 | * we provide here anyway and strips it immediately. | |
251 | */ | |
252 | memcpy(skb->data + transfer, &rxdesc->icv, 4); | |
253 | transfer += icv_len; | |
2bb057d0 ID |
254 | |
255 | /* IV/EIV/ICV has been inserted into frame */ | |
256 | rxdesc->size = transfer; | |
257 | rxdesc->flags &= ~RX_FLAG_IV_STRIPPED; | |
258 | } |