mac80211: fix typo in a comment
[safe/jmp/linux-2.6] / net / mac80211 / wep.c
index 9bf0e1c..8a980f1 100644 (file)
@@ -17,6 +17,7 @@
 #include <linux/err.h>
 #include <linux/mm.h>
 #include <linux/scatterlist.h>
+#include <asm/unaligned.h>
 
 #include <net/mac80211.h>
 #include "ieee80211_i.h"
@@ -31,13 +32,13 @@ int ieee80211_wep_init(struct ieee80211_local *local)
        local->wep_tx_tfm = crypto_alloc_blkcipher("ecb(arc4)", 0,
                                                CRYPTO_ALG_ASYNC);
        if (IS_ERR(local->wep_tx_tfm))
-               return -ENOMEM;
+               return PTR_ERR(local->wep_tx_tfm);
 
        local->wep_rx_tfm = crypto_alloc_blkcipher("ecb(arc4)", 0,
                                                CRYPTO_ALG_ASYNC);
        if (IS_ERR(local->wep_rx_tfm)) {
                crypto_free_blkcipher(local->wep_tx_tfm);
-               return -ENOMEM;
+               return PTR_ERR(local->wep_rx_tfm);
        }
 
        return 0;
@@ -49,25 +50,27 @@ void ieee80211_wep_free(struct ieee80211_local *local)
        crypto_free_blkcipher(local->wep_rx_tfm);
 }
 
-static inline int ieee80211_wep_weak_iv(u32 iv, int keylen)
+static inline bool ieee80211_wep_weak_iv(u32 iv, int keylen)
 {
-       /* Fluhrer, Mantin, and Shamir have reported weaknesses in the
+       /*
+        * Fluhrer, Mantin, and Shamir have reported weaknesses in the
         * key scheduling algorithm of RC4. At least IVs (KeyByte + 3,
-        * 0xff, N) can be used to speedup attacks, so avoid using them. */
+        * 0xff, N) can be used to speedup attacks, so avoid using them.
+        */
        if ((iv & 0xff00) == 0xff00) {
                u8 B = (iv >> 16) & 0xff;
                if (B >= 3 && B < 3 + keylen)
-                       return 1;
+                       return true;
        }
-       return 0;
+       return false;
 }
 
 
 static void ieee80211_wep_get_iv(struct ieee80211_local *local,
-                                struct ieee80211_key *key, u8 *iv)
+                                int keylen, int keyidx, u8 *iv)
 {
        local->wep_iv++;
-       if (ieee80211_wep_weak_iv(local->wep_iv, key->conf.keylen))
+       if (ieee80211_wep_weak_iv(local->wep_iv, keylen))
                local->wep_iv += 0x0100;
 
        if (!iv)
@@ -76,35 +79,28 @@ static void ieee80211_wep_get_iv(struct ieee80211_local *local,
        *iv++ = (local->wep_iv >> 16) & 0xff;
        *iv++ = (local->wep_iv >> 8) & 0xff;
        *iv++ = local->wep_iv & 0xff;
-       *iv++ = key->conf.keyidx << 6;
+       *iv++ = keyidx << 6;
 }
 
 
 static u8 *ieee80211_wep_add_iv(struct ieee80211_local *local,
                                struct sk_buff *skb,
-                               struct ieee80211_key *key)
+                               int keylen, int keyidx)
 {
-       struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
-       u16 fc;
-       int hdrlen;
+       struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
+       unsigned int hdrlen;
        u8 *newhdr;
 
-       fc = le16_to_cpu(hdr->frame_control);
-       fc |= IEEE80211_FCTL_PROTECTED;
-       hdr->frame_control = cpu_to_le16(fc);
+       hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
 
-       if ((skb_headroom(skb) < WEP_IV_LEN ||
-            skb_tailroom(skb) < WEP_ICV_LEN)) {
-               I802_DEBUG_INC(local->tx_expand_skb_head);
-               if (unlikely(pskb_expand_head(skb, WEP_IV_LEN, WEP_ICV_LEN,
-                                             GFP_ATOMIC)))
-                       return NULL;
-       }
+       if (WARN_ON(skb_tailroom(skb) < WEP_ICV_LEN ||
+                   skb_headroom(skb) < WEP_IV_LEN))
+               return NULL;
 
-       hdrlen = ieee80211_get_hdrlen(fc);
+       hdrlen = ieee80211_hdrlen(hdr->frame_control);
        newhdr = skb_push(skb, WEP_IV_LEN);
        memmove(newhdr, newhdr + WEP_IV_LEN, hdrlen);
-       ieee80211_wep_get_iv(local, key, newhdr + hdrlen);
+       ieee80211_wep_get_iv(local, keylen, keyidx, newhdr + hdrlen);
        return newhdr + hdrlen;
 }
 
@@ -113,12 +109,10 @@ static void ieee80211_wep_remove_iv(struct ieee80211_local *local,
                                    struct sk_buff *skb,
                                    struct ieee80211_key *key)
 {
-       struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
-       u16 fc;
-       int hdrlen;
+       struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
+       unsigned int hdrlen;
 
-       fc = le16_to_cpu(hdr->frame_control);
-       hdrlen = ieee80211_get_hdrlen(fc);
+       hdrlen = ieee80211_hdrlen(hdr->frame_control);
        memmove(skb->data + WEP_IV_LEN, skb->data, hdrlen);
        skb_pull(skb, WEP_IV_LEN);
 }
@@ -132,10 +126,10 @@ void ieee80211_wep_encrypt_data(struct crypto_blkcipher *tfm, u8 *rc4key,
 {
        struct blkcipher_desc desc = { .tfm = tfm };
        struct scatterlist sg;
-       __le32 *icv;
+       __le32 icv;
 
-       icv = (__le32 *)(data + data_len);
-       *icv = cpu_to_le32(~crc32_le(~0, data, data_len));
+       icv = cpu_to_le32(~crc32_le(~0, data, data_len));
+       put_unaligned(icv, (__le32 *)(data + data_len));
 
        crypto_blkcipher_setkey(tfm, rc4key, klen);
        sg_init_one(&sg, data, data_len + WEP_ICV_LEN);
@@ -150,43 +144,32 @@ void ieee80211_wep_encrypt_data(struct crypto_blkcipher *tfm, u8 *rc4key,
  *
  * WEP frame payload: IV + TX key idx, RC4(data), ICV = RC4(CRC32(data))
  */
-int ieee80211_wep_encrypt(struct ieee80211_local *local, struct sk_buff *skb,
-                         struct ieee80211_key *key)
+int ieee80211_wep_encrypt(struct ieee80211_local *local,
+                         struct sk_buff *skb,
+                         const u8 *key, int keylen, int keyidx)
 {
-       u32 klen;
-       u8 *rc4key, *iv;
+       u8 *iv;
        size_t len;
+       u8 rc4key[3 + WLAN_KEY_LEN_WEP104];
 
-       if (!key || key->conf.alg != ALG_WEP)
-               return -1;
-
-       klen = 3 + key->conf.keylen;
-       rc4key = kmalloc(klen, GFP_ATOMIC);
-       if (!rc4key)
+       iv = ieee80211_wep_add_iv(local, skb, keylen, keyidx);
+       if (!iv)
                return -1;
 
-       iv = ieee80211_wep_add_iv(local, skb, key);
-       if (!iv) {
-               kfree(rc4key);
-               return -1;
-       }
-
        len = skb->len - (iv + WEP_IV_LEN - skb->data);
 
        /* Prepend 24-bit IV to RC4 key */
        memcpy(rc4key, iv, 3);
 
        /* Copy rest of the WEP key (the secret part) */
-       memcpy(rc4key + 3, key->conf.key, key->conf.keylen);
+       memcpy(rc4key + 3, keykeylen);
 
        /* Add room for ICV */
        skb_put(skb, WEP_ICV_LEN);
 
-       ieee80211_wep_encrypt_data(local->wep_tx_tfm, rc4key, klen,
+       ieee80211_wep_encrypt_data(local->wep_tx_tfm, rc4key, keylen + 3,
                                   iv + WEP_IV_LEN, len);
 
-       kfree(rc4key);
-
        return 0;
 }
 
@@ -222,28 +205,26 @@ int ieee80211_wep_decrypt_data(struct crypto_blkcipher *tfm, u8 *rc4key,
  * failure. If frame is OK, IV and ICV will be removed, i.e., decrypted payload
  * is moved to the beginning of the skb and skb length will be reduced.
  */
-int ieee80211_wep_decrypt(struct ieee80211_local *local, struct sk_buff *skb,
-                         struct ieee80211_key *key)
+static int ieee80211_wep_decrypt(struct ieee80211_local *local,
+                                struct sk_buff *skb,
+                                struct ieee80211_key *key)
 {
        u32 klen;
        u8 *rc4key;
        u8 keyidx;
-       struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
-       u16 fc;
-       int hdrlen;
+       struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
+       unsigned int hdrlen;
        size_t len;
        int ret = 0;
 
-       fc = le16_to_cpu(hdr->frame_control);
-       if (!(fc & IEEE80211_FCTL_PROTECTED))
+       if (!ieee80211_has_protected(hdr->frame_control))
                return -1;
 
-       hdrlen = ieee80211_get_hdrlen(fc);
-
-       if (skb->len < 8 + hdrlen)
+       hdrlen = ieee80211_hdrlen(hdr->frame_control);
+       if (skb->len < hdrlen + WEP_IV_LEN + WEP_ICV_LEN)
                return -1;
 
-       len = skb->len - hdrlen - 8;
+       len = skb->len - hdrlen - WEP_IV_LEN - WEP_ICV_LEN;
 
        keyidx = skb->data[hdrlen + 3] >> 6;
 
@@ -264,10 +245,8 @@ int ieee80211_wep_decrypt(struct ieee80211_local *local, struct sk_buff *skb,
 
        if (ieee80211_wep_decrypt_data(local->wep_rx_tfm, rc4key, klen,
                                       skb->data + hdrlen + WEP_IV_LEN,
-                                      len)) {
-               printk(KERN_DEBUG "WEP decrypt failed (ICV)\n");
+                                      len))
                ret = -1;
-       }
 
        kfree(rc4key);
 
@@ -282,101 +261,79 @@ int ieee80211_wep_decrypt(struct ieee80211_local *local, struct sk_buff *skb,
 }
 
 
-u8 * ieee80211_wep_is_weak_iv(struct sk_buff *skb, struct ieee80211_key *key)
+bool ieee80211_wep_is_weak_iv(struct sk_buff *skb, struct ieee80211_key *key)
 {
-       struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
-       u16 fc;
-       int hdrlen;
+       struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
+       unsigned int hdrlen;
        u8 *ivpos;
        u32 iv;
 
-       fc = le16_to_cpu(hdr->frame_control);
-       if (!(fc & IEEE80211_FCTL_PROTECTED))
-               return NULL;
+       if (!ieee80211_has_protected(hdr->frame_control))
+               return false;
 
-       hdrlen = ieee80211_get_hdrlen(fc);
+       hdrlen = ieee80211_hdrlen(hdr->frame_control);
        ivpos = skb->data + hdrlen;
        iv = (ivpos[0] << 16) | (ivpos[1] << 8) | ivpos[2];
 
-       if (ieee80211_wep_weak_iv(iv, key->conf.keylen))
-               return ivpos;
-
-       return NULL;
+       return ieee80211_wep_weak_iv(iv, key->conf.keylen);
 }
 
-ieee80211_txrx_result
-ieee80211_crypto_wep_decrypt(struct ieee80211_txrx_data *rx)
+ieee80211_rx_result
+ieee80211_crypto_wep_decrypt(struct ieee80211_rx_data *rx)
 {
-       if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
-           ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
-            (rx->fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH))
-               return TXRX_CONTINUE;
-
-       if (!(rx->u.rx.status->flag & RX_FLAG_DECRYPTED)) {
-               if (ieee80211_wep_decrypt(rx->local, rx->skb, rx->key)) {
-#ifdef CONFIG_MAC80211_DEBUG
-                       if (net_ratelimit())
-                               printk(KERN_DEBUG "%s: RX WEP frame, decrypt "
-                                      "failed\n", rx->dev->name);
-#endif /* CONFIG_MAC80211_DEBUG */
-                       return TXRX_DROP;
-               }
-       } else if (!(rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED)) {
+       struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
+
+       if (!ieee80211_is_data(hdr->frame_control) &&
+           !ieee80211_is_auth(hdr->frame_control))
+               return RX_CONTINUE;
+
+       if (!(rx->status->flag & RX_FLAG_DECRYPTED)) {
+               if (ieee80211_wep_decrypt(rx->local, rx->skb, rx->key))
+                       return RX_DROP_UNUSABLE;
+       } else if (!(rx->status->flag & RX_FLAG_IV_STRIPPED)) {
                ieee80211_wep_remove_iv(rx->local, rx->skb, rx->key);
                /* remove ICV */
-               skb_trim(rx->skb, rx->skb->len - 4);
+               skb_trim(rx->skb, rx->skb->len - WEP_ICV_LEN);
        }
 
-       return TXRX_CONTINUE;
+       return RX_CONTINUE;
 }
 
-static int wep_encrypt_skb(struct ieee80211_txrx_data *tx, struct sk_buff *skb)
+static int wep_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb)
 {
+       struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+
        if (!(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) {
-               if (ieee80211_wep_encrypt(tx->local, skb, tx->key))
+               if (ieee80211_wep_encrypt(tx->local, skb, tx->key->conf.key,
+                                         tx->key->conf.keylen,
+                                         tx->key->conf.keyidx))
                        return -1;
        } else {
-               tx->u.tx.control->key_idx = tx->key->conf.hw_key_idx;
+               info->control.hw_key = &tx->key->conf;
                if (tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) {
-                       if (!ieee80211_wep_add_iv(tx->local, skb, tx->key))
+                       if (!ieee80211_wep_add_iv(tx->local, skb,
+                                                 tx->key->conf.keylen,
+                                                 tx->key->conf.keyidx))
                                return -1;
                }
        }
        return 0;
 }
 
-ieee80211_txrx_result
-ieee80211_crypto_wep_encrypt(struct ieee80211_txrx_data *tx)
+ieee80211_tx_result
+ieee80211_crypto_wep_encrypt(struct ieee80211_tx_data *tx)
 {
-       struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;
-       u16 fc;
-
-       fc = le16_to_cpu(hdr->frame_control);
-
-       if (((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA &&
-            ((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_MGMT ||
-             (fc & IEEE80211_FCTL_STYPE) != IEEE80211_STYPE_AUTH)))
-               return TXRX_CONTINUE;
+       struct sk_buff *skb;
 
-       tx->u.tx.control->iv_len = WEP_IV_LEN;
-       tx->u.tx.control->icv_len = WEP_ICV_LEN;
-       ieee80211_tx_set_iswep(tx);
+       ieee80211_tx_set_protected(tx);
 
-       if (wep_encrypt_skb(tx, tx->skb) < 0) {
-               I802_DEBUG_INC(tx->local->tx_handlers_drop_wep);
-               return TXRX_DROP;
-       }
-
-       if (tx->u.tx.extra_frag) {
-               int i;
-               for (i = 0; i < tx->u.tx.num_extra_frag; i++) {
-                       if (wep_encrypt_skb(tx, tx->u.tx.extra_frag[i]) < 0) {
-                               I802_DEBUG_INC(tx->local->
-                                              tx_handlers_drop_wep);
-                               return TXRX_DROP;
-                       }
+       skb = tx->skb;
+       do {
+               if (wep_encrypt_skb(tx, skb) < 0) {
+                       I802_DEBUG_INC(tx->local->tx_handlers_drop_wep);
+                       return TX_DROP;
                }
-       }
+       } while ((skb = skb->next));
 
-       return TXRX_CONTINUE;
+       return TX_CONTINUE;
 }