From: Ivo van Doorn Date: Thu, 20 Nov 2008 22:29:36 +0000 (+0100) Subject: rt2x00: Implement HW encryption (rt2500usb) X-Git-Url: http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Fivd%2Frt2x00.git;a=commitdiff_plain;h=52fe465ab5eb6aeead5ac8d91dd70e363d0560b7 rt2x00: Implement HW encryption (rt2500usb) rt2500usb supports hardware encryption. rt2500usb supports up to 4 shared and pairwise keys. Signed-off-by: Ivo van Doorn --- diff --git a/drivers/net/wireless/rt2x00/rt2500usb.c b/drivers/net/wireless/rt2x00/rt2500usb.c index 10cb46a..620ac65 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 = 0; +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 +330,85 @@ static void rt2500usb_init_led(struct rt2x00_dev *rt2x00dev, /* * 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; + + /* Support up to 4 keys */ + if (key->hw_key_idx >= 4) + return -ENOSPC; + + 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, ®); + + if ((reg & mask) && (reg & mask) == 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 +930,7 @@ static int rt2500usb_init_registers(struct rt2x00_dev *rt2x00dev) 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 +1152,7 @@ static void rt2500usb_write_tx_desc(struct rt2x00_dev *rt2x00dev, * 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 +1165,11 @@ static void rt2500usb_write_tx_desc(struct rt2x00_dev *rt2x00dev, 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); + _rt2x00_desc_write(txd, 4, skbdesc->eiv); + } + 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 +1184,8 @@ static void rt2500usb_write_tx_desc(struct rt2x00_dev *rt2x00dev, 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 +1296,7 @@ static void rt2500usb_kick_tx_queue(struct rt2x00_dev *rt2x00dev, 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 +1324,31 @@ static void rt2500usb_fill_rxdone(struct queue_entry *entry, 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); + _rt2x00_desc_read(rxd, 3, &rxdesc->eiv); + /* 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 +1356,8 @@ static void rt2500usb_fill_rxdone(struct queue_entry *entry, * 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)) @@ -1729,6 +1847,8 @@ static int rt2500usb_probe_hw(struct rt2x00_dev *rt2x00dev) __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_DISABLE_LINK_TUNING, &rt2x00dev->flags); /* @@ -1748,6 +1868,7 @@ static const struct ieee80211_ops rt2500usb_mac80211_ops = { .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, @@ -1769,6 +1890,8 @@ static const struct rt2x00lib_ops rt2500usb_rt2x00_ops = { .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, diff --git a/drivers/net/wireless/rt2x00/rt2500usb.h b/drivers/net/wireless/rt2x00/rt2500usb.h index dbb5d68..4347dfd 100644 --- a/drivers/net/wireless/rt2x00/rt2500usb.h +++ b/drivers/net/wireless/rt2x00/rt2500usb.h @@ -447,6 +447,9 @@ #define SEC_CSR30 0x04bc #define SEC_CSR31 0x04be +#define KEY_ENTRY(__idx) \ + ( SEC_CSR0 + ((__idx) * 16) ) + /* * PHY control registers. */