rt2x00: Implement HW encryption (rt2500usb)
rt2500usb supports hardware encryption.
rt2500usb supports up to 4 shared and pairwise keys.
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/rt2x00/rt2500usb.c b/drivers/net/wireless/rt2x00/rt2500usb.c
index 0447e93..90bf0b9 100644
--- a/drivers/net/wireless/rt2x00/rt2500usb.c
+++ b/drivers/net/wireless/rt2x00/rt2500usb.c
@@ -36,6 +36,13 @@
#include "rt2500usb.h"
/*
+ * Allow hardware encryption to be disabled.
+ */
+static int modparam_nohwcrypt = 1;
+module_param_named(nohwcrypt, modparam_nohwcrypt, bool, S_IRUGO);
+MODULE_PARM_DESC(nohwcrypt, "Disable hardware encryption.");
+
+/*
* Register access.
* All access to the CSR registers will go through the methods
* rt2500usb_register_read and rt2500usb_register_write.
@@ -323,6 +330,82 @@
/*
* Configuration handlers.
*/
+
+/*
+ * rt2500usb does not differentiate between shared and pairwise
+ * keys, so we should use the same function for both key types.
+ */
+static int rt2500usb_config_key(struct rt2x00_dev *rt2x00dev,
+ struct rt2x00lib_crypto *crypto,
+ struct ieee80211_key_conf *key)
+{
+ int timeout;
+ u32 mask;
+ u16 reg;
+
+ if (crypto->cmd == SET_KEY) {
+ /*
+ * Pairwise key will always be entry 0, but this
+ * could collide with a shared key on the same
+ * position...
+ */
+ mask = TXRX_CSR0_KEY_ID.bit_mask;
+
+ rt2500usb_register_read(rt2x00dev, TXRX_CSR0, ®);
+ reg &= mask;
+
+ if (reg && reg == mask)
+ return -ENOSPC;
+
+ reg = rt2x00_get_field16(reg, TXRX_CSR0_KEY_ID);
+
+ key->hw_key_idx += reg ? ffz(reg) : 0;
+
+ /*
+ * The encryption key doesn't fit within the CSR cache,
+ * this means we should allocate it seperately and use
+ * rt2x00usb_vendor_request() to send the key to the hardware.
+ */
+ reg = KEY_ENTRY(key->hw_key_idx);
+ timeout = REGISTER_TIMEOUT32(sizeof(crypto->key));
+ rt2x00usb_vendor_request_large_buff(rt2x00dev, USB_MULTI_WRITE,
+ USB_VENDOR_REQUEST_OUT, reg,
+ crypto->key,
+ sizeof(crypto->key),
+ timeout);
+
+ /*
+ * The driver does not support the IV/EIV generation
+ * in hardware. However it doesn't support the IV/EIV
+ * inside the ieee80211 frame either, but requires it
+ * to be provided seperately for the descriptor.
+ * rt2x00lib will cut the IV/EIV data out of all frames
+ * given to us by mac80211, but we must tell mac80211
+ * to generate the IV/EIV data.
+ */
+ key->flags |= IEEE80211_KEY_FLAG_GENERATE_IV;
+ key->flags |= IEEE80211_KEY_FLAG_GENERATE_MMIC;
+ }
+
+ /*
+ * TXRX_CSR0_KEY_ID contains only single-bit fields to indicate
+ * a particular key is valid.
+ */
+ rt2500usb_register_read(rt2x00dev, TXRX_CSR0, ®);
+ rt2x00_set_field16(®, TXRX_CSR0_ALGORITHM, crypto->cipher);
+ rt2x00_set_field16(®, TXRX_CSR0_IV_OFFSET, IEEE80211_HEADER);
+
+ mask = rt2x00_get_field16(reg, TXRX_CSR0_KEY_ID);
+ if (crypto->cmd == SET_KEY)
+ mask |= 1 << key->hw_key_idx;
+ else if (crypto->cmd == DISABLE_KEY)
+ mask &= ~(1 << key->hw_key_idx);
+ rt2x00_set_field16(®, TXRX_CSR0_KEY_ID, mask);
+ rt2500usb_register_write(rt2x00dev, TXRX_CSR0, reg);
+
+ return 0;
+}
+
static void rt2500usb_config_filter(struct rt2x00_dev *rt2x00dev,
const unsigned int filter_flags)
{
@@ -844,7 +927,7 @@
rt2500usb_register_read(rt2x00dev, TXRX_CSR0, ®);
rt2x00_set_field16(®, TXRX_CSR0_IV_OFFSET, IEEE80211_HEADER);
- rt2x00_set_field16(®, TXRX_CSR0_KEY_ID, 0xff);
+ rt2x00_set_field16(®, TXRX_CSR0_KEY_ID, 0);
rt2500usb_register_write(rt2x00dev, TXRX_CSR0, reg);
rt2500usb_register_read(rt2x00dev, MAC_CSR18, ®);
@@ -1066,7 +1149,7 @@
* Start writing the descriptor words.
*/
rt2x00_desc_read(txd, 1, &word);
- rt2x00_set_field32(&word, TXD_W1_IV_OFFSET, IEEE80211_HEADER);
+ rt2x00_set_field32(&word, TXD_W1_IV_OFFSET, txdesc->iv_offset);
rt2x00_set_field32(&word, TXD_W1_AIFS, txdesc->aifs);
rt2x00_set_field32(&word, TXD_W1_CWMIN, txdesc->cw_min);
rt2x00_set_field32(&word, TXD_W1_CWMAX, txdesc->cw_max);
@@ -1079,6 +1162,11 @@
rt2x00_set_field32(&word, TXD_W2_PLCP_LENGTH_HIGH, txdesc->length_high);
rt2x00_desc_write(txd, 2, word);
+ if (test_bit(ENTRY_TXD_ENCRYPT, &txdesc->flags)) {
+ _rt2x00_desc_write(txd, 3, skbdesc->iv[0]);
+ _rt2x00_desc_write(txd, 4, skbdesc->iv[1]);
+ }
+
rt2x00_desc_read(txd, 0, &word);
rt2x00_set_field32(&word, TXD_W0_RETRY_LIMIT, txdesc->retry_limit);
rt2x00_set_field32(&word, TXD_W0_MORE_FRAG,
@@ -1093,7 +1181,8 @@
test_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags));
rt2x00_set_field32(&word, TXD_W0_IFS, txdesc->ifs);
rt2x00_set_field32(&word, TXD_W0_DATABYTE_COUNT, skb->len);
- rt2x00_set_field32(&word, TXD_W0_CIPHER, CIPHER_NONE);
+ rt2x00_set_field32(&word, TXD_W0_CIPHER, txdesc->cipher);
+ rt2x00_set_field32(&word, TXD_W0_KEY_ID, txdesc->key_idx);
rt2x00_desc_write(txd, 0, word);
}
@@ -1204,6 +1293,7 @@
static void rt2500usb_fill_rxdone(struct queue_entry *entry,
struct rxdone_entry_desc *rxdesc)
{
+ struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
struct queue_entry_priv_usb *entry_priv = entry->priv_data;
struct skb_frame_desc *skbdesc = get_skb_frame_desc(entry->skb);
__le32 *rxd =
@@ -1231,6 +1321,31 @@
if (rt2x00_get_field32(word0, RXD_W0_PHYSICAL_ERROR))
rxdesc->flags |= RX_FLAG_FAILED_PLCP_CRC;
+ if (test_bit(CONFIG_SUPPORT_HW_CRYPTO, &rt2x00dev->flags)) {
+ rxdesc->cipher = rt2x00_get_field32(word0, RXD_W0_CIPHER);
+ if (rt2x00_get_field32(word0, RXD_W0_CIPHER_ERROR))
+ rxdesc->cipher_status = RX_CRYPTO_FAIL_KEY;
+ }
+
+ if (rxdesc->cipher != CIPHER_NONE) {
+ _rt2x00_desc_read(rxd, 2, &rxdesc->iv[0]);
+ _rt2x00_desc_read(rxd, 3, &rxdesc->iv[1]);
+ /* ICV is located at the end of frame */
+
+ /*
+ * Hardware has stripped IV/EIV data from 802.11 frame during
+ * decryption. It has provided the data seperately but rt2x00lib
+ * should decide if it should be reinserted.
+ */
+ rxdesc->flags |= RX_FLAG_IV_STRIPPED;
+ if (rxdesc->cipher != CIPHER_TKIP)
+ rxdesc->flags |= RX_FLAG_MMIC_STRIPPED;
+ if (rxdesc->cipher_status == RX_CRYPTO_SUCCESS)
+ rxdesc->flags |= RX_FLAG_DECRYPTED;
+ else if (rxdesc->cipher_status == RX_CRYPTO_FAIL_MIC)
+ rxdesc->flags |= RX_FLAG_MMIC_ERROR;
+ }
+
/*
* Obtain the status about this packet.
* When frame was received with an OFDM bitrate,
@@ -1238,8 +1353,8 @@
* a CCK bitrate the signal is the rate in 100kbit/s.
*/
rxdesc->signal = rt2x00_get_field32(word1, RXD_W1_SIGNAL);
- rxdesc->rssi = rt2x00_get_field32(word1, RXD_W1_RSSI) -
- entry->queue->rt2x00dev->rssi_offset;
+ rxdesc->rssi =
+ rt2x00_get_field32(word1, RXD_W1_RSSI) - rt2x00dev->rssi_offset;
rxdesc->size = rt2x00_get_field32(word0, RXD_W0_DATABYTE_COUNT);
if (rt2x00_get_field32(word0, RXD_W0_OFDM))
@@ -1727,6 +1842,10 @@
__set_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags);
__set_bit(DRIVER_REQUIRE_BEACON_GUARD, &rt2x00dev->flags);
__set_bit(DRIVER_REQUIRE_SCHEDULED, &rt2x00dev->flags);
+ if (!modparam_nohwcrypt) {
+ __set_bit(CONFIG_SUPPORT_HW_CRYPTO, &rt2x00dev->flags);
+ __set_bit(CONFIG_CRYPTO_COPY_IV, &rt2x00dev->flags);
+ }
__set_bit(CONFIG_DISABLE_LINK_TUNING, &rt2x00dev->flags);
/*
@@ -1746,6 +1865,7 @@
.config = rt2x00mac_config,
.config_interface = rt2x00mac_config_interface,
.configure_filter = rt2x00mac_configure_filter,
+ .set_key = rt2x00mac_set_key,
.get_stats = rt2x00mac_get_stats,
.bss_info_changed = rt2x00mac_bss_info_changed,
.conf_tx = rt2x00mac_conf_tx,
@@ -1767,6 +1887,8 @@
.get_tx_data_len = rt2500usb_get_tx_data_len,
.kick_tx_queue = rt2500usb_kick_tx_queue,
.fill_rxdone = rt2500usb_fill_rxdone,
+ .config_shared_key = rt2500usb_config_key,
+ .config_pairwise_key = rt2500usb_config_key,
.config_filter = rt2500usb_config_filter,
.config_intf = rt2500usb_config_intf,
.config_erp = rt2500usb_config_erp,