diff options
Diffstat (limited to 'drivers/net/wireless/ath/key.c')
| -rw-r--r-- | drivers/net/wireless/ath/key.c | 609 |
1 files changed, 609 insertions, 0 deletions
diff --git a/drivers/net/wireless/ath/key.c b/drivers/net/wireless/ath/key.c new file mode 100644 index 000000000..1816b4e7d --- /dev/null +++ b/drivers/net/wireless/ath/key.c @@ -0,0 +1,609 @@ +/* + * Copyright (c) 2009 Atheros Communications Inc. + * Copyright (c) 2010 Bruno Randolf <br1@einfach.org> + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#include <linux/export.h> +#include <asm/unaligned.h> +#include <net/mac80211.h> + +#include "ath.h" +#include "reg.h" + +#define REG_READ (common->ops->read) +#define REG_WRITE(_ah, _reg, _val) (common->ops->write)(_ah, _val, _reg) +#define ENABLE_REGWRITE_BUFFER(_ah) \ + if (common->ops->enable_write_buffer) \ + common->ops->enable_write_buffer((_ah)); + +#define REGWRITE_BUFFER_FLUSH(_ah) \ + if (common->ops->write_flush) \ + common->ops->write_flush((_ah)); + + +#define IEEE80211_WEP_NKID 4 /* number of key ids */ + +/************************/ +/* Key Cache Management */ +/************************/ + +bool ath_hw_keyreset(struct ath_common *common, u16 entry) +{ + u32 keyType; + void *ah = common->ah; + + if (entry >= common->keymax) { + ath_err(common, "keyreset: keycache entry %u out of range\n", + entry); + return false; + } + + keyType = REG_READ(ah, AR_KEYTABLE_TYPE(entry)); + + ENABLE_REGWRITE_BUFFER(ah); + + REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), 0); + REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), 0); + REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), 0); + REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), 0); + REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), 0); + REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), AR_KEYTABLE_TYPE_CLR); + REG_WRITE(ah, AR_KEYTABLE_MAC0(entry), 0); + REG_WRITE(ah, AR_KEYTABLE_MAC1(entry), 0); + + if (keyType == AR_KEYTABLE_TYPE_TKIP) { + u16 micentry = entry + 64; + + REG_WRITE(ah, AR_KEYTABLE_KEY0(micentry), 0); + REG_WRITE(ah, AR_KEYTABLE_KEY1(micentry), 0); + REG_WRITE(ah, AR_KEYTABLE_KEY2(micentry), 0); + REG_WRITE(ah, AR_KEYTABLE_KEY3(micentry), 0); + if (common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED) { + REG_WRITE(ah, AR_KEYTABLE_KEY4(micentry), 0); + REG_WRITE(ah, AR_KEYTABLE_TYPE(micentry), + AR_KEYTABLE_TYPE_CLR); + } + + } + + REGWRITE_BUFFER_FLUSH(ah); + + return true; +} +EXPORT_SYMBOL(ath_hw_keyreset); + +static bool ath_hw_keysetmac(struct ath_common *common, + u16 entry, const u8 *mac) +{ + u32 macHi, macLo; + u32 unicast_flag = AR_KEYTABLE_VALID; + void *ah = common->ah; + + if (entry >= common->keymax) { + ath_err(common, "keysetmac: keycache entry %u out of range\n", + entry); + return false; + } + + if (mac != NULL) { + /* + * AR_KEYTABLE_VALID indicates that the address is a unicast + * address, which must match the transmitter address for + * decrypting frames. + * Not setting this bit allows the hardware to use the key + * for multicast frame decryption. + */ + if (mac[0] & 0x01) + unicast_flag = 0; + + macLo = get_unaligned_le32(mac); + macHi = get_unaligned_le16(mac + 4); + macLo >>= 1; + macLo |= (macHi & 1) << 31; + macHi >>= 1; + } else { + macLo = macHi = 0; + } + ENABLE_REGWRITE_BUFFER(ah); + + REG_WRITE(ah, AR_KEYTABLE_MAC0(entry), macLo); + REG_WRITE(ah, AR_KEYTABLE_MAC1(entry), macHi | unicast_flag); + + REGWRITE_BUFFER_FLUSH(ah); + + return true; +} + +static bool ath_hw_set_keycache_entry(struct ath_common *common, u16 entry, + const struct ath_keyval *k, + const u8 *mac) +{ + void *ah = common->ah; + u32 key0, key1, key2, key3, key4; + u32 keyType; + + if (entry >= common->keymax) { + ath_err(common, "set-entry: keycache entry %u out of range\n", + entry); + return false; + } + + switch (k->kv_type) { + case ATH_CIPHER_AES_OCB: + keyType = AR_KEYTABLE_TYPE_AES; + break; + case ATH_CIPHER_AES_CCM: + if (!(common->crypt_caps & ATH_CRYPT_CAP_CIPHER_AESCCM)) { + ath_dbg(common, ANY, + "AES-CCM not supported by this mac rev\n"); + return false; + } + keyType = AR_KEYTABLE_TYPE_CCM; + break; + case ATH_CIPHER_TKIP: + keyType = AR_KEYTABLE_TYPE_TKIP; + if (entry + 64 >= common->keymax) { + ath_dbg(common, ANY, + "entry %u inappropriate for TKIP\n", entry); + return false; + } + break; + case ATH_CIPHER_WEP: + if (k->kv_len < WLAN_KEY_LEN_WEP40) { + ath_dbg(common, ANY, "WEP key length %u too small\n", + k->kv_len); + return false; + } + if (k->kv_len <= WLAN_KEY_LEN_WEP40) + keyType = AR_KEYTABLE_TYPE_40; + else if (k->kv_len <= WLAN_KEY_LEN_WEP104) + keyType = AR_KEYTABLE_TYPE_104; + else + keyType = AR_KEYTABLE_TYPE_128; + break; + case ATH_CIPHER_CLR: + keyType = AR_KEYTABLE_TYPE_CLR; + break; + default: + ath_err(common, "cipher %u not supported\n", k->kv_type); + return false; + } + + key0 = get_unaligned_le32(k->kv_val + 0); + key1 = get_unaligned_le16(k->kv_val + 4); + key2 = get_unaligned_le32(k->kv_val + 6); + key3 = get_unaligned_le16(k->kv_val + 10); + key4 = get_unaligned_le32(k->kv_val + 12); + if (k->kv_len <= WLAN_KEY_LEN_WEP104) + key4 &= 0xff; + + /* + * Note: Key cache registers access special memory area that requires + * two 32-bit writes to actually update the values in the internal + * memory. Consequently, the exact order and pairs used here must be + * maintained. + */ + + if (keyType == AR_KEYTABLE_TYPE_TKIP) { + u16 micentry = entry + 64; + + /* + * Write inverted key[47:0] first to avoid Michael MIC errors + * on frames that could be sent or received at the same time. + * The correct key will be written in the end once everything + * else is ready. + */ + REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), ~key0); + REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), ~key1); + + /* Write key[95:48] */ + REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), key2); + REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), key3); + + /* Write key[127:96] and key type */ + REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), key4); + REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), keyType); + + /* Write MAC address for the entry */ + (void) ath_hw_keysetmac(common, entry, mac); + + if (common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED) { + /* + * TKIP uses two key cache entries: + * Michael MIC TX/RX keys in the same key cache entry + * (idx = main index + 64): + * key0 [31:0] = RX key [31:0] + * key1 [15:0] = TX key [31:16] + * key1 [31:16] = reserved + * key2 [31:0] = RX key [63:32] + * key3 [15:0] = TX key [15:0] + * key3 [31:16] = reserved + * key4 [31:0] = TX key [63:32] + */ + u32 mic0, mic1, mic2, mic3, mic4; + + mic0 = get_unaligned_le32(k->kv_mic + 0); + mic2 = get_unaligned_le32(k->kv_mic + 4); + mic1 = get_unaligned_le16(k->kv_txmic + 2) & 0xffff; + mic3 = get_unaligned_le16(k->kv_txmic + 0) & 0xffff; + mic4 = get_unaligned_le32(k->kv_txmic + 4); + + ENABLE_REGWRITE_BUFFER(ah); + + /* Write RX[31:0] and TX[31:16] */ + REG_WRITE(ah, AR_KEYTABLE_KEY0(micentry), mic0); + REG_WRITE(ah, AR_KEYTABLE_KEY1(micentry), mic1); + + /* Write RX[63:32] and TX[15:0] */ + REG_WRITE(ah, AR_KEYTABLE_KEY2(micentry), mic2); + REG_WRITE(ah, AR_KEYTABLE_KEY3(micentry), mic3); + + /* Write TX[63:32] and keyType(reserved) */ + REG_WRITE(ah, AR_KEYTABLE_KEY4(micentry), mic4); + REG_WRITE(ah, AR_KEYTABLE_TYPE(micentry), + AR_KEYTABLE_TYPE_CLR); + + REGWRITE_BUFFER_FLUSH(ah); + + } else { + /* + * TKIP uses four key cache entries (two for group + * keys): + * Michael MIC TX/RX keys are in different key cache + * entries (idx = main index + 64 for TX and + * main index + 32 + 96 for RX): + * key0 [31:0] = TX/RX MIC key [31:0] + * key1 [31:0] = reserved + * key2 [31:0] = TX/RX MIC key [63:32] + * key3 [31:0] = reserved + * key4 [31:0] = reserved + * + * Upper layer code will call this function separately + * for TX and RX keys when these registers offsets are + * used. + */ + u32 mic0, mic2; + + mic0 = get_unaligned_le32(k->kv_mic + 0); + mic2 = get_unaligned_le32(k->kv_mic + 4); + + ENABLE_REGWRITE_BUFFER(ah); + + /* Write MIC key[31:0] */ + REG_WRITE(ah, AR_KEYTABLE_KEY0(micentry), mic0); + REG_WRITE(ah, AR_KEYTABLE_KEY1(micentry), 0); + + /* Write MIC key[63:32] */ + REG_WRITE(ah, AR_KEYTABLE_KEY2(micentry), mic2); + REG_WRITE(ah, AR_KEYTABLE_KEY3(micentry), 0); + + /* Write TX[63:32] and keyType(reserved) */ + REG_WRITE(ah, AR_KEYTABLE_KEY4(micentry), 0); + REG_WRITE(ah, AR_KEYTABLE_TYPE(micentry), + AR_KEYTABLE_TYPE_CLR); + + REGWRITE_BUFFER_FLUSH(ah); + } + + ENABLE_REGWRITE_BUFFER(ah); + + /* MAC address registers are reserved for the MIC entry */ + REG_WRITE(ah, AR_KEYTABLE_MAC0(micentry), 0); + REG_WRITE(ah, AR_KEYTABLE_MAC1(micentry), 0); + + /* + * Write the correct (un-inverted) key[47:0] last to enable + * TKIP now that all other registers are set with correct + * values. + */ + REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), key0); + REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), key1); + + REGWRITE_BUFFER_FLUSH(ah); + } else { + ENABLE_REGWRITE_BUFFER(ah); + + /* Write key[47:0] */ + REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), key0); + REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), key1); + + /* Write key[95:48] */ + REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), key2); + REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), key3); + + /* Write key[127:96] and key type */ + REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), key4); + REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), keyType); + + REGWRITE_BUFFER_FLUSH(ah); + + /* Write MAC address for the entry */ + (void) ath_hw_keysetmac(common, entry, mac); + } + + return true; +} + +static int ath_setkey_tkip(struct ath_common *common, u16 keyix, const u8 *key, + struct ath_keyval *hk, const u8 *addr, + bool authenticator) +{ + const u8 *key_rxmic; + const u8 *key_txmic; + + key_txmic = key + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY; + key_rxmic = key + NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY; + + if (addr == NULL) { + /* + * Group key installation - only two key cache entries are used + * regardless of splitmic capability since group key is only + * used either for TX or RX. + */ + if (authenticator) { + memcpy(hk->kv_mic, key_txmic, sizeof(hk->kv_mic)); + memcpy(hk->kv_txmic, key_txmic, sizeof(hk->kv_mic)); + } else { + memcpy(hk->kv_mic, key_rxmic, sizeof(hk->kv_mic)); + memcpy(hk->kv_txmic, key_rxmic, sizeof(hk->kv_mic)); + } + return ath_hw_set_keycache_entry(common, keyix, hk, addr); + } + if (common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED) { + /* TX and RX keys share the same key cache entry. */ + memcpy(hk->kv_mic, key_rxmic, sizeof(hk->kv_mic)); + memcpy(hk->kv_txmic, key_txmic, sizeof(hk->kv_txmic)); + return ath_hw_set_keycache_entry(common, keyix, hk, addr); + } + + /* Separate key cache entries for TX and RX */ + + /* TX key goes at first index, RX key at +32. */ + memcpy(hk->kv_mic, key_txmic, sizeof(hk->kv_mic)); + if (!ath_hw_set_keycache_entry(common, keyix, hk, NULL)) { + /* TX MIC entry failed. No need to proceed further */ + ath_err(common, "Setting TX MIC Key Failed\n"); + return 0; + } + + memcpy(hk->kv_mic, key_rxmic, sizeof(hk->kv_mic)); + /* XXX delete tx key on failure? */ + return ath_hw_set_keycache_entry(common, keyix + 32, hk, addr); +} + +static int ath_reserve_key_cache_slot_tkip(struct ath_common *common) +{ + int i; + + for (i = IEEE80211_WEP_NKID; i < common->keymax / 2; i++) { + if (test_bit(i, common->keymap) || + test_bit(i + 64, common->keymap)) + continue; /* At least one part of TKIP key allocated */ + if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED) && + (test_bit(i + 32, common->keymap) || + test_bit(i + 64 + 32, common->keymap))) + continue; /* At least one part of TKIP key allocated */ + + /* Found a free slot for a TKIP key */ + return i; + } + return -1; +} + +static int ath_reserve_key_cache_slot(struct ath_common *common, + u32 cipher) +{ + int i; + + if (cipher == WLAN_CIPHER_SUITE_TKIP) + return ath_reserve_key_cache_slot_tkip(common); + + /* First, try to find slots that would not be available for TKIP. */ + if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED)) { + for (i = IEEE80211_WEP_NKID; i < common->keymax / 4; i++) { + if (!test_bit(i, common->keymap) && + (test_bit(i + 32, common->keymap) || + test_bit(i + 64, common->keymap) || + test_bit(i + 64 + 32, common->keymap))) + return i; + if (!test_bit(i + 32, common->keymap) && + (test_bit(i, common->keymap) || + test_bit(i + 64, common->keymap) || + test_bit(i + 64 + 32, common->keymap))) + return i + 32; + if (!test_bit(i + 64, common->keymap) && + (test_bit(i , common->keymap) || + test_bit(i + 32, common->keymap) || + test_bit(i + 64 + 32, common->keymap))) + return i + 64; + if (!test_bit(i + 64 + 32, common->keymap) && + (test_bit(i, common->keymap) || + test_bit(i + 32, common->keymap) || + test_bit(i + 64, common->keymap))) + return i + 64 + 32; + } + } else { + for (i = IEEE80211_WEP_NKID; i < common->keymax / 2; i++) { + if (!test_bit(i, common->keymap) && + test_bit(i + 64, common->keymap)) + return i; + if (test_bit(i, common->keymap) && + !test_bit(i + 64, common->keymap)) + return i + 64; + } + } + + /* No partially used TKIP slots, pick any available slot */ + for (i = IEEE80211_WEP_NKID; i < common->keymax; i++) { + /* Do not allow slots that could be needed for TKIP group keys + * to be used. This limitation could be removed if we know that + * TKIP will not be used. */ + if (i >= 64 && i < 64 + IEEE80211_WEP_NKID) + continue; + if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED)) { + if (i >= 32 && i < 32 + IEEE80211_WEP_NKID) + continue; + if (i >= 64 + 32 && i < 64 + 32 + IEEE80211_WEP_NKID) + continue; + } + + if (!test_bit(i, common->keymap)) + return i; /* Found a free slot for a key */ + } + + /* No free slot found */ + return -1; +} + +/* + * Configure encryption in the HW. + */ +int ath_key_config(struct ath_common *common, + struct ieee80211_vif *vif, + struct ieee80211_sta *sta, + struct ieee80211_key_conf *key) +{ + struct ath_keyval hk; + const u8 *mac = NULL; + u8 gmac[ETH_ALEN]; + int ret = 0; + int idx; + + memset(&hk, 0, sizeof(hk)); + + switch (key->cipher) { + case 0: + hk.kv_type = ATH_CIPHER_CLR; + break; + case WLAN_CIPHER_SUITE_WEP40: + case WLAN_CIPHER_SUITE_WEP104: + hk.kv_type = ATH_CIPHER_WEP; + break; + case WLAN_CIPHER_SUITE_TKIP: + hk.kv_type = ATH_CIPHER_TKIP; + break; + case WLAN_CIPHER_SUITE_CCMP: + hk.kv_type = ATH_CIPHER_AES_CCM; + break; + default: + return -EOPNOTSUPP; + } + + hk.kv_len = key->keylen; + if (key->keylen) + memcpy(hk.kv_val, key->key, key->keylen); + + if (!(key->flags & IEEE80211_KEY_FLAG_PAIRWISE)) { + switch (vif->type) { + case NL80211_IFTYPE_AP: + memcpy(gmac, vif->addr, ETH_ALEN); + gmac[0] |= 0x01; + mac = gmac; + idx = ath_reserve_key_cache_slot(common, key->cipher); + break; + case NL80211_IFTYPE_ADHOC: + if (!sta) { + idx = key->keyidx; + break; + } + memcpy(gmac, sta->addr, ETH_ALEN); + gmac[0] |= 0x01; + mac = gmac; + idx = ath_reserve_key_cache_slot(common, key->cipher); + break; + default: + idx = key->keyidx; + break; + } + } else if (key->keyidx) { + if (WARN_ON(!sta)) + return -EOPNOTSUPP; + mac = sta->addr; + + if (vif->type != NL80211_IFTYPE_AP) { + /* Only keyidx 0 should be used with unicast key, but + * allow this for client mode for now. */ + idx = key->keyidx; + } else + return -EIO; + } else { + if (WARN_ON(!sta)) + return -EOPNOTSUPP; + mac = sta->addr; + + idx = ath_reserve_key_cache_slot(common, key->cipher); + } + + if (idx < 0) + return -ENOSPC; /* no free key cache entries */ + + if (key->cipher == WLAN_CIPHER_SUITE_TKIP) + ret = ath_setkey_tkip(common, idx, key->key, &hk, mac, + vif->type == NL80211_IFTYPE_AP); + else + ret = ath_hw_set_keycache_entry(common, idx, &hk, mac); + + if (!ret) + return -EIO; + + set_bit(idx, common->keymap); + if (key->cipher == WLAN_CIPHER_SUITE_CCMP) + set_bit(idx, common->ccmp_keymap); + + if (key->cipher == WLAN_CIPHER_SUITE_TKIP) { + set_bit(idx + 64, common->keymap); + set_bit(idx, common->tkip_keymap); + set_bit(idx + 64, common->tkip_keymap); + if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED)) { + set_bit(idx + 32, common->keymap); + set_bit(idx + 64 + 32, common->keymap); + set_bit(idx + 32, common->tkip_keymap); + set_bit(idx + 64 + 32, common->tkip_keymap); + } + } + + return idx; +} +EXPORT_SYMBOL(ath_key_config); + +/* + * Delete Key. + */ +void ath_key_delete(struct ath_common *common, struct ieee80211_key_conf *key) +{ + ath_hw_keyreset(common, key->hw_key_idx); + if (key->hw_key_idx < IEEE80211_WEP_NKID) + return; + + clear_bit(key->hw_key_idx, common->keymap); + clear_bit(key->hw_key_idx, common->ccmp_keymap); + if (key->cipher != WLAN_CIPHER_SUITE_TKIP) + return; + + clear_bit(key->hw_key_idx + 64, common->keymap); + + clear_bit(key->hw_key_idx, common->tkip_keymap); + clear_bit(key->hw_key_idx + 64, common->tkip_keymap); + + if (!(common->crypt_caps & ATH_CRYPT_CAP_MIC_COMBINED)) { + ath_hw_keyreset(common, key->hw_key_idx + 32); + clear_bit(key->hw_key_idx + 32, common->keymap); + clear_bit(key->hw_key_idx + 64 + 32, common->keymap); + + clear_bit(key->hw_key_idx + 32, common->tkip_keymap); + clear_bit(key->hw_key_idx + 64 + 32, common->tkip_keymap); + } +} +EXPORT_SYMBOL(ath_key_delete); |