p54: utilize cryptographic accelerator

This patch allows p54 to utilize its WEP, TKIP and CCMP accelerator.

Tested-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Christian Lamparter <chunkeey@web.de>
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/p54/p54.h b/drivers/net/wireless/p54/p54.h
index 491ab96c7b67f57318302f358fcd90282358aa45..ebe1ea1f565b3d696ae5ce380d168e52173db570 100644 (file)
--- a/drivers/net/wireless/p54/p54.h
+++ b/drivers/net/wireless/p54/p54.h
@@ -115,6 +115,8 @@ struct p54_common {
        int noise;
        void *eeprom;
        struct completion eeprom_comp;
+       u8 privacy_caps;
+       u8 rx_keycache_size;
 };
 
 int p54_rx(struct ieee80211_hw *dev, struct sk_buff *skb);

diff --git a/drivers/net/wireless/p54/p54common.c b/drivers/net/wireless/p54/p54common.c
index de92b58d4508e775a6a59e9816b719153be4aaaa..6f7e82b56cbeee2370c34cca469b5b88439491e2 100644 (file)
--- a/drivers/net/wireless/p54/p54common.c
+++ b/drivers/net/wireless/p54/p54common.c
@@ -25,6 +25,9 @@
 #include "p54.h"
 #include "p54common.h"
 
+static int modparam_nohwcrypt;
+module_param_named(nohwcrypt, modparam_nohwcrypt, bool, S_IRUGO);
+MODULE_PARM_DESC(nohwcrypt, "Disable hardware encryption.");
 MODULE_AUTHOR("Michael Wu <flamingice@sourmilk.net>");
 MODULE_DESCRIPTION("Softmac Prism54 common code");
 MODULE_LICENSE("GPL");
@@ -185,6 +188,8 @@ int p54_parse_firmware(struct ieee80211_hw *dev, const struct firmware *fw)
                        priv->rx_end = le32_to_cpu(desc->rx_end) - 0x3500;
                        priv->headroom = desc->headroom;
                        priv->tailroom = desc->tailroom;
+                       priv->privacy_caps = desc->privacy_caps;
+                       priv->rx_keycache_size = desc->rx_keycache_size;
                        if (le32_to_cpu(bootrec->len) == 11)
                                priv->rx_mtu = le16_to_cpu(desc->rx_mtu);
                        else
@@ -228,6 +233,16 @@ int p54_parse_firmware(struct ieee80211_hw *dev, const struct firmware *fw)
                dev->queues = 4;
        }
 
+       if (!modparam_nohwcrypt)
+               printk(KERN_INFO "%s: cryptographic accelerator "
+                                "WEP:%s, TKIP:%s, CCMP:%s\n",
+                       wiphy_name(dev->wiphy),
+                       (priv->privacy_caps & BR_DESC_PRIV_CAP_WEP) ? "YES" :
+                       "no", (priv->privacy_caps & (BR_DESC_PRIV_CAP_TKIP |
+                        BR_DESC_PRIV_CAP_MICHAEL)) ? "YES" : "no",
+                       (priv->privacy_caps & BR_DESC_PRIV_CAP_AESCCMP) ?
+                       "YES" : "no");
+
        return 0;
 }
 EXPORT_SYMBOL_GPL(p54_parse_firmware);
@@ -526,6 +541,12 @@ static int p54_rx_data(struct ieee80211_hw *dev, struct sk_buff *skb)
                        return 0;
        }
 
+       if (hdr->decrypt_status == P54_DECRYPT_OK)
+               rx_status.flag |= RX_FLAG_DECRYPTED;
+       if ((hdr->decrypt_status == P54_DECRYPT_FAIL_MICHAEL) ||
+           (hdr->decrypt_status == P54_DECRYPT_FAIL_TKIP))
+               rx_status.flag |= RX_FLAG_MMIC_ERROR;
+
        rx_status.signal = p54_rssi_to_dbm(dev, hdr->rssi);
        rx_status.noise = priv->noise;
        /* XX correct? */
@@ -1107,6 +1128,20 @@ static int p54_tx_fill(struct ieee80211_hw *dev, struct sk_buff *skb,
        return ret;
 }
 
+static u8 p54_convert_algo(enum ieee80211_key_alg alg)
+{
+       switch (alg) {
+       case ALG_WEP:
+               return P54_CRYPTO_WEP;
+       case ALG_TKIP:
+               return P54_CRYPTO_TKIPMICHAEL;
+       case ALG_CCMP:
+               return P54_CRYPTO_AESCCMP;
+       default:
+               return 0;
+       }
+}
+
 static int p54_tx(struct ieee80211_hw *dev, struct sk_buff *skb)
 {
        struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
@@ -1117,7 +1152,7 @@ static int p54_tx(struct ieee80211_hw *dev, struct sk_buff *skb)
        size_t padding, len, tim_len = 0;
        int i, j, ridx, ret;
        u16 hdr_flags = 0, aid = 0;
-       u8 rate, queue;
+       u8 rate, queue, crypt_offset = 0;
        u8 cts_rate = 0x20;
        u8 rc_flags;
        u8 calculated_tries[4];
@@ -1137,12 +1172,25 @@ static int p54_tx(struct ieee80211_hw *dev, struct sk_buff *skb)
        padding = (unsigned long)(skb->data - (sizeof(*hdr) + sizeof(*txhdr))) & 3;
        len = skb->len;
 
+       if (info->control.hw_key) {
+               crypt_offset = ieee80211_get_hdrlen_from_skb(skb);
+               if (info->control.hw_key->alg == ALG_TKIP) {
+                       u8 *iv = (u8 *)(skb->data + crypt_offset);
+                       /*
+                        * The firmware excepts that the IV has to have
+                        * this special format
+                        */
+                       iv[1] = iv[0];
+                       iv[0] = iv[2];
+                       iv[2] = 0;
+               }
+       }
+
        txhdr = (struct p54_tx_data *) skb_push(skb, sizeof(*txhdr) + padding);
        hdr = (struct p54_hdr *) skb_push(skb, sizeof(*hdr));
 
        if (padding)
                hdr_flags |= P54_HDR_FLAG_DATA_ALIGN;
-       hdr->len = cpu_to_le16(len);
        hdr->type = cpu_to_le16(aid);
        hdr->rts_tries = info->control.rates[0].count;
 
@@ -1217,10 +1265,27 @@ static int p54_tx(struct ieee80211_hw *dev, struct sk_buff *skb)
        /* TODO: enable bursting */
        hdr->flags = cpu_to_le16(hdr_flags);
        hdr->tries = ridx;
-       txhdr->crypt_offset = 0;
        txhdr->rts_rate_idx = 0;
-       txhdr->key_type = 0;
-       txhdr->key_len = 0;
+       if (info->control.hw_key) {
+               crypt_offset += info->control.hw_key->iv_len;
+               txhdr->key_type = p54_convert_algo(info->control.hw_key->alg);
+               txhdr->key_len = min((u8)16, info->control.hw_key->keylen);
+               memcpy(txhdr->key, info->control.hw_key->key, txhdr->key_len);
+               if (info->control.hw_key->alg == ALG_TKIP) {
+                       if (unlikely(skb_tailroom(skb) < 12))
+                               goto err;
+                       /* reserve space for the MIC key */
+                       len += 8;
+                       memcpy(skb_put(skb, 8), &(info->control.hw_key->key
+                               [NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY]), 8);
+               }
+               /* reserve some space for ICV */
+               len += info->control.hw_key->icv_len;
+       } else {
+               txhdr->key_type = 0;
+               txhdr->key_len = 0;
+       }
+       txhdr->crypt_offset = crypt_offset;
        txhdr->hw_queue = queue;
        if (current_queue)
                txhdr->backlog = current_queue->len;
@@ -1234,17 +1299,20 @@ static int p54_tx(struct ieee80211_hw *dev, struct sk_buff *skb)
        if (padding)
                txhdr->align[0] = padding;
 
+       hdr->len = cpu_to_le16(len);
        /* modifies skb->cb and with it info, so must be last! */
-       if (unlikely(p54_assign_address(dev, skb, hdr, skb->len + tim_len))) {
-               skb_pull(skb, sizeof(*hdr) + sizeof(*txhdr) + padding);
-               if (current_queue) {
-                       current_queue->len--;
-                       current_queue->count--;
-               }
-               return NETDEV_TX_BUSY;
-       }
+       if (unlikely(p54_assign_address(dev, skb, hdr, skb->len + tim_len)))
+               goto err;
        priv->tx(dev, skb, 0);
        return 0;
+
+ err:
+       skb_pull(skb, sizeof(*hdr) + sizeof(*txhdr) + padding);
+       if (current_queue) {
+               current_queue->len--;
+               current_queue->count--;
+       }
+       return NETDEV_TX_BUSY;
 }
 
 static int p54_setup_mac(struct ieee80211_hw *dev, u16 mode, const u8 *bssid)
@@ -1848,6 +1916,90 @@ static void p54_bss_info_changed(struct ieee80211_hw *dev,
 
 }
 
+static int p54_set_key(struct ieee80211_hw *dev, enum set_key_cmd cmd,
+                      const u8 *local_address, const u8 *address,
+                      struct ieee80211_key_conf *key)
+{
+       struct p54_common *priv = dev->priv;
+       struct sk_buff *skb;
+       struct p54_keycache *rxkey;
+       u8 algo = 0;
+
+       if (modparam_nohwcrypt)
+               return -EOPNOTSUPP;
+
+       if (cmd == DISABLE_KEY)
+               algo = 0;
+       else {
+               switch (key->alg) {
+               case ALG_TKIP:
+                       if (!(priv->privacy_caps & (BR_DESC_PRIV_CAP_MICHAEL |
+                             BR_DESC_PRIV_CAP_TKIP)))
+                               return -EOPNOTSUPP;
+                       key->flags |= IEEE80211_KEY_FLAG_GENERATE_IV;
+                       algo = P54_CRYPTO_TKIPMICHAEL;
+                       break;
+               case ALG_WEP:
+                       if (!(priv->privacy_caps & BR_DESC_PRIV_CAP_WEP))
+                               return -EOPNOTSUPP;
+                       key->flags |= IEEE80211_KEY_FLAG_GENERATE_IV;
+                       algo = P54_CRYPTO_WEP;
+                       break;
+               case ALG_CCMP:
+                       if (!(priv->privacy_caps & BR_DESC_PRIV_CAP_AESCCMP))
+                               return -EOPNOTSUPP;
+                       key->flags |= IEEE80211_KEY_FLAG_GENERATE_IV;
+                       algo = P54_CRYPTO_AESCCMP;
+                       break;
+               default:
+                       return -EINVAL;
+               }
+       }
+
+       if (key->keyidx > priv->rx_keycache_size) {
+               /*
+                * The device supports the choosen algorithm, but the firmware
+                * does not provide enough key slots to store all of them.
+                * So, incoming frames have to be decoded by the mac80211 stack,
+                * but we can still offload encryption for outgoing frames.
+                */
+
+               return 0;
+       }
+
+       mutex_lock(&priv->conf_mutex);
+       skb = p54_alloc_skb(dev, P54_HDR_FLAG_CONTROL_OPSET, sizeof(*rxkey) +
+                       sizeof(struct p54_hdr), P54_CONTROL_TYPE_RX_KEYCACHE,
+                       GFP_ATOMIC);
+       if (!skb) {
+               mutex_unlock(&priv->conf_mutex);
+               return -ENOMEM;
+       }
+
+       /* TODO: some devices have 4 more free slots for rx keys */
+       rxkey = (struct p54_keycache *)skb_put(skb, sizeof(*rxkey));
+       rxkey->entry = key->keyidx;
+       rxkey->key_id = key->keyidx;
+       rxkey->key_type = algo;
+       if (address)
+               memcpy(rxkey->mac, address, ETH_ALEN);
+       else
+               memset(rxkey->mac, ~0, ETH_ALEN);
+       if (key->alg != ALG_TKIP) {
+               rxkey->key_len = min((u8)16, key->keylen);
+               memcpy(rxkey->key, key->key, rxkey->key_len);
+       } else {
+               rxkey->key_len = 24;
+               memcpy(rxkey->key, key->key, 16);
+               memcpy(&(rxkey->key[16]), &(key->key
+                       [NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY]), 8);
+       }
+
+       priv->tx(dev, skb, 1);
+       mutex_unlock(&priv->conf_mutex);
+       return 0;
+}
+
 static const struct ieee80211_ops p54_ops = {
        .tx                     = p54_tx,
        .start                  = p54_start,
@@ -1857,6 +2009,7 @@ static const struct ieee80211_ops p54_ops = {
        .set_tim                = p54_set_tim,
        .sta_notify_ps          = p54_sta_notify_ps,
        .sta_notify             = p54_sta_notify,
+       .set_key                = p54_set_key,
        .config                 = p54_config,
        .config_interface       = p54_config_interface,
        .bss_info_changed       = p54_bss_info_changed,