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path: root/drivers/net/wireless/rt2x00/rt2x00crypto.c
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Diffstat (limited to 'drivers/net/wireless/rt2x00/rt2x00crypto.c')
-rw-r--r--drivers/net/wireless/rt2x00/rt2x00crypto.c256
1 files changed, 256 insertions, 0 deletions
diff --git a/drivers/net/wireless/rt2x00/rt2x00crypto.c b/drivers/net/wireless/rt2x00/rt2x00crypto.c
new file mode 100644
index 000000000..a2fd05ba2
--- /dev/null
+++ b/drivers/net/wireless/rt2x00/rt2x00crypto.c
@@ -0,0 +1,256 @@
+/*
+ Copyright (C) 2004 - 2009 Ivo van Doorn <IvDoorn@gmail.com>
+ <http://rt2x00.serialmonkey.com>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ Module: rt2x00lib
+ Abstract: rt2x00 crypto specific routines.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+#include "rt2x00.h"
+#include "rt2x00lib.h"
+
+enum cipher rt2x00crypto_key_to_cipher(struct ieee80211_key_conf *key)
+{
+ switch (key->cipher) {
+ case WLAN_CIPHER_SUITE_WEP40:
+ return CIPHER_WEP64;
+ case WLAN_CIPHER_SUITE_WEP104:
+ return CIPHER_WEP128;
+ case WLAN_CIPHER_SUITE_TKIP:
+ return CIPHER_TKIP;
+ case WLAN_CIPHER_SUITE_CCMP:
+ return CIPHER_AES;
+ default:
+ return CIPHER_NONE;
+ }
+}
+
+void rt2x00crypto_create_tx_descriptor(struct rt2x00_dev *rt2x00dev,
+ struct sk_buff *skb,
+ struct txentry_desc *txdesc)
+{
+ struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
+ struct ieee80211_key_conf *hw_key = tx_info->control.hw_key;
+
+ if (!rt2x00_has_cap_hw_crypto(rt2x00dev) || !hw_key)
+ return;
+
+ __set_bit(ENTRY_TXD_ENCRYPT, &txdesc->flags);
+
+ txdesc->cipher = rt2x00crypto_key_to_cipher(hw_key);
+
+ if (hw_key->flags & IEEE80211_KEY_FLAG_PAIRWISE)
+ __set_bit(ENTRY_TXD_ENCRYPT_PAIRWISE, &txdesc->flags);
+
+ txdesc->key_idx = hw_key->hw_key_idx;
+ txdesc->iv_offset = txdesc->header_length;
+ txdesc->iv_len = hw_key->iv_len;
+
+ if (!(hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV))
+ __set_bit(ENTRY_TXD_ENCRYPT_IV, &txdesc->flags);
+
+ if (!(hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_MMIC))
+ __set_bit(ENTRY_TXD_ENCRYPT_MMIC, &txdesc->flags);
+}
+
+unsigned int rt2x00crypto_tx_overhead(struct rt2x00_dev *rt2x00dev,
+ struct sk_buff *skb)
+{
+ struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
+ struct ieee80211_key_conf *key = tx_info->control.hw_key;
+ unsigned int overhead = 0;
+
+ if (!rt2x00_has_cap_hw_crypto(rt2x00dev) || !key)
+ return overhead;
+
+ /*
+ * Extend frame length to include IV/EIV/ICV/MMIC,
+ * note that these lengths should only be added when
+ * mac80211 does not generate it.
+ */
+ overhead += key->icv_len;
+
+ if (!(key->flags & IEEE80211_KEY_FLAG_GENERATE_IV))
+ overhead += key->iv_len;
+
+ if (!(key->flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) {
+ if (key->cipher == WLAN_CIPHER_SUITE_TKIP)
+ overhead += 8;
+ }
+
+ return overhead;
+}
+
+void rt2x00crypto_tx_copy_iv(struct sk_buff *skb, struct txentry_desc *txdesc)
+{
+ struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb);
+
+ if (unlikely(!txdesc->iv_len))
+ return;
+
+ /* Copy IV/EIV data */
+ memcpy(skbdesc->iv, skb->data + txdesc->iv_offset, txdesc->iv_len);
+}
+
+void rt2x00crypto_tx_remove_iv(struct sk_buff *skb, struct txentry_desc *txdesc)
+{
+ struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb);
+
+ if (unlikely(!txdesc->iv_len))
+ return;
+
+ /* Copy IV/EIV data */
+ memcpy(skbdesc->iv, skb->data + txdesc->iv_offset, txdesc->iv_len);
+
+ /* Move ieee80211 header */
+ memmove(skb->data + txdesc->iv_len, skb->data, txdesc->iv_offset);
+
+ /* Pull buffer to correct size */
+ skb_pull(skb, txdesc->iv_len);
+ txdesc->length -= txdesc->iv_len;
+
+ /* IV/EIV data has officially been stripped */
+ skbdesc->flags |= SKBDESC_IV_STRIPPED;
+}
+
+void rt2x00crypto_tx_insert_iv(struct sk_buff *skb, unsigned int header_length)
+{
+ struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb);
+ const unsigned int iv_len =
+ ((!!(skbdesc->iv[0])) * 4) + ((!!(skbdesc->iv[1])) * 4);
+
+ if (!(skbdesc->flags & SKBDESC_IV_STRIPPED))
+ return;
+
+ skb_push(skb, iv_len);
+
+ /* Move ieee80211 header */
+ memmove(skb->data, skb->data + iv_len, header_length);
+
+ /* Copy IV/EIV data */
+ memcpy(skb->data + header_length, skbdesc->iv, iv_len);
+
+ /* IV/EIV data has returned into the frame */
+ skbdesc->flags &= ~SKBDESC_IV_STRIPPED;
+}
+
+void rt2x00crypto_rx_insert_iv(struct sk_buff *skb,
+ unsigned int header_length,
+ struct rxdone_entry_desc *rxdesc)
+{
+ unsigned int payload_len = rxdesc->size - header_length;
+ unsigned int align = ALIGN_SIZE(skb, header_length);
+ unsigned int iv_len;
+ unsigned int icv_len;
+ unsigned int transfer = 0;
+
+ /*
+ * WEP64/WEP128: Provides IV & ICV
+ * TKIP: Provides IV/EIV & ICV
+ * AES: Provies IV/EIV & ICV
+ */
+ switch (rxdesc->cipher) {
+ case CIPHER_WEP64:
+ case CIPHER_WEP128:
+ iv_len = 4;
+ icv_len = 4;
+ break;
+ case CIPHER_TKIP:
+ iv_len = 8;
+ icv_len = 4;
+ break;
+ case CIPHER_AES:
+ iv_len = 8;
+ icv_len = 8;
+ break;
+ default:
+ /* Unsupport type */
+ return;
+ }
+
+ /*
+ * Make room for new data. There are 2 possibilities
+ * either the alignment is already present between
+ * the 802.11 header and payload. In that case we
+ * we have to move the header less then the iv_len
+ * since we can use the already available l2pad bytes
+ * for the iv data.
+ * When the alignment must be added manually we must
+ * move the header more then iv_len since we must
+ * make room for the payload move as well.
+ */
+ if (rxdesc->dev_flags & RXDONE_L2PAD) {
+ skb_push(skb, iv_len - align);
+ skb_put(skb, icv_len);
+
+ /* Move ieee80211 header */
+ memmove(skb->data + transfer,
+ skb->data + transfer + (iv_len - align),
+ header_length);
+ transfer += header_length;
+ } else {
+ skb_push(skb, iv_len + align);
+ if (align < icv_len)
+ skb_put(skb, icv_len - align);
+ else if (align > icv_len)
+ skb_trim(skb, rxdesc->size + iv_len + icv_len);
+
+ /* Move ieee80211 header */
+ memmove(skb->data + transfer,
+ skb->data + transfer + iv_len + align,
+ header_length);
+ transfer += header_length;
+ }
+
+ /* Copy IV/EIV data */
+ memcpy(skb->data + transfer, rxdesc->iv, iv_len);
+ transfer += iv_len;
+
+ /*
+ * Move payload for alignment purposes. Note that
+ * this is only needed when no l2 padding is present.
+ */
+ if (!(rxdesc->dev_flags & RXDONE_L2PAD)) {
+ memmove(skb->data + transfer,
+ skb->data + transfer + align,
+ payload_len);
+ }
+
+ /*
+ * NOTE: Always count the payload as transferred,
+ * even when alignment was set to zero. This is required
+ * for determining the correct offset for the ICV data.
+ */
+ transfer += payload_len;
+
+ /*
+ * Copy ICV data
+ * AES appends 8 bytes, we can't fill the upper
+ * 4 bytes, but mac80211 doesn't care about what
+ * we provide here anyway and strips it immediately.
+ */
+ memcpy(skb->data + transfer, &rxdesc->icv, 4);
+ transfer += icv_len;
+
+ /* IV/EIV/ICV has been inserted into frame */
+ rxdesc->size = transfer;
+ rxdesc->flags &= ~RX_FLAG_IV_STRIPPED;
+}
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-03 00:00:19 +0000