mac80211: add generic cipher scheme support

[deliverable/linux.git] / net / mac80211 / rx.c

diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 401f3c26e707444ea62e5600b5d9a19aebd34922..79f76791f77a26ad79deabf9213914f4d1ace610 100644 (file)
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -638,6 +638,27 @@ static int ieee80211_get_mmie_keyidx(struct sk_buff *skb)
        return le16_to_cpu(mmie->key_id);
 }
 
+static int iwl80211_get_cs_keyid(const struct ieee80211_cipher_scheme *cs,
+                                struct sk_buff *skb)
+{
+       struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
+       __le16 fc;
+       int hdrlen;
+       u8 keyid;
+
+       fc = hdr->frame_control;
+       hdrlen = ieee80211_hdrlen(fc);
+
+       if (skb->len < hdrlen + cs->hdr_len)
+               return -EINVAL;
+
+       skb_copy_bits(skb, hdrlen + cs->key_idx_off, &keyid, 1);
+       keyid &= cs->key_idx_mask;
+       keyid >>= cs->key_idx_shift;
+
+       return keyid;
+}
+
 static ieee80211_rx_result ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
 {
        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
@@ -1360,6 +1381,7 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
        struct ieee80211_key *sta_ptk = NULL;
        int mmie_keyidx = -1;
        __le16 fc;
+       const struct ieee80211_cipher_scheme *cs = NULL;
 
        /*
         * Key selection 101
@@ -1397,11 +1419,19 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
 
        /* start without a key */
        rx->key = NULL;
+       fc = hdr->frame_control;
 
-       if (rx->sta)
-               sta_ptk = rcu_dereference(rx->sta->ptk);
+       if (rx->sta) {
+               int keyid = rx->sta->ptk_idx;
 
-       fc = hdr->frame_control;
+               if (ieee80211_has_protected(fc) && rx->sta->cipher_scheme) {
+                       cs = rx->sta->cipher_scheme;
+                       keyid = iwl80211_get_cs_keyid(cs, rx->skb);
+                       if (unlikely(keyid < 0))
+                               return RX_DROP_UNUSABLE;
+               }
+               sta_ptk = rcu_dereference(rx->sta->ptk[keyid]);
+       }
 
        if (!ieee80211_has_protected(fc))
                mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
@@ -1463,6 +1493,7 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
                return RX_CONTINUE;
        } else {
                u8 keyid;
+
                /*
                 * The device doesn't give us the IV so we won't be
                 * able to look up the key. That's ok though, we
@@ -1478,15 +1509,21 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
 
                hdrlen = ieee80211_hdrlen(fc);
 
-               if (rx->skb->len < 8 + hdrlen)
-                       return RX_DROP_UNUSABLE; /* TODO: count this? */
+               if (cs) {
+                       keyidx = iwl80211_get_cs_keyid(cs, rx->skb);
 
-               /*
-                * no need to call ieee80211_wep_get_keyidx,
-                * it verifies a bunch of things we've done already
-                */
-               skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
-               keyidx = keyid >> 6;
+                       if (unlikely(keyidx < 0))
+                               return RX_DROP_UNUSABLE;
+               } else {
+                       if (rx->skb->len < 8 + hdrlen)
+                               return RX_DROP_UNUSABLE; /* TODO: count this? */
+                       /*
+                        * no need to call ieee80211_wep_get_keyidx,
+                        * it verifies a bunch of things we've done already
+                        */
+                       skb_copy_bits(rx->skb, hdrlen + 3, &keyid, 1);
+                       keyidx = keyid >> 6;
+               }
 
                /* check per-station GTK first, if multicast packet */
                if (is_multicast_ether_addr(hdr->addr1) && rx->sta)
@@ -1534,11 +1571,7 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
                result = ieee80211_crypto_aes_cmac_decrypt(rx);
                break;
        default:
-               /*
-                * We can reach here only with HW-only algorithms
-                * but why didn't it decrypt the frame?!
-                */
-               return RX_DROP_UNUSABLE;
+               result = ieee80211_crypto_hw_decrypt(rx);
        }
 
        /* the hdr variable is invalid after the decrypt handlers */