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path: root/drivers/net/wireless/ath/key.c
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Diffstat (limited to 'drivers/net/wireless/ath/key.c')
-rw-r--r--drivers/net/wireless/ath/key.c568
1 files changed, 568 insertions, 0 deletions
diff --git a/drivers/net/wireless/ath/key.c b/drivers/net/wireless/ath/key.c
new file mode 100644
index 000000000000..bd21a4d82085
--- /dev/null
+++ b/drivers/net/wireless/ath/key.c
@@ -0,0 +1,568 @@
+/*
+ * 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 <asm/unaligned.h>
+#include <net/mac80211.h>
+
+#include "ath.h"
+#include "reg.h"
+#include "debug.h"
+
+#define REG_READ (common->ops->read)
+#define REG_WRITE(_ah, _reg, _val) (common->ops->write)(_ah, _val, _reg)
+
+#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_print(common, ATH_DBG_FATAL,
+ "keychache entry %u out of range\n", entry);
+ return false;
+ }
+
+ keyType = REG_READ(ah, AR_KEYTABLE_TYPE(entry));
+
+ 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);
+
+ }
+
+ return true;
+}
+EXPORT_SYMBOL(ath_hw_keyreset);
+
+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_print(common, ATH_DBG_FATAL,
+ "keychache 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;
+
+ macHi = (mac[5] << 8) | mac[4];
+ macLo = (mac[3] << 24) |
+ (mac[2] << 16) |
+ (mac[1] << 8) |
+ mac[0];
+ macLo >>= 1;
+ macLo |= (macHi & 1) << 31;
+ macHi >>= 1;
+ } else {
+ macLo = macHi = 0;
+ }
+ REG_WRITE(ah, AR_KEYTABLE_MAC0(entry), macLo);
+ REG_WRITE(ah, AR_KEYTABLE_MAC1(entry), macHi | unicast_flag);
+
+ return true;
+}
+
+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_print(common, ATH_DBG_FATAL,
+ "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_print(common, ATH_DBG_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_print(common, ATH_DBG_ANY,
+ "entry %u inappropriate for TKIP\n", entry);
+ return false;
+ }
+ break;
+ case ATH_CIPHER_WEP:
+ if (k->kv_len < WLAN_KEY_LEN_WEP40) {
+ ath_print(common, ATH_DBG_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_print(common, ATH_DBG_FATAL,
+ "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);
+
+ /* 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);
+
+ } 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);
+
+ /* 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);
+ }
+
+ /* 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);
+ } else {
+ /* 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);
+
+ /* 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_print(common, ATH_DBG_FATAL,
+ "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 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;
+ 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_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);
+ 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);