mac80211: move tx crypto decision

This patch moves the decision making about whether a frame is encrypted
with a certain algorithm up into the TX handlers rather than having it
in the crypto algorithm implementation.

This fixes a problem with the radiotap injection code where injecting
a non-data packet and requesting encryption could end up asking the
driver to encrypt a packet without giving it a key.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 22 insertions, 41 deletions

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index f7aff2e97eea..8302c70da9a4 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -438,11 +438,7 @@ static ieee80211_txrx_result
 ieee80211_tx_h_select_key(struct ieee80211_txrx_data *tx)
 {
         struct ieee80211_key *key;
-        const struct ieee80211_hdr *hdr;
-        u16 fc;
-
-        hdr = (const struct ieee80211_hdr *) tx->skb->data;
-        fc = le16_to_cpu(hdr->frame_control);
+        u16 fc = tx->fc;
 
         if (unlikely(tx->u.tx.control->flags & IEEE80211_TXCTL_DO_NOT_ENCRYPT))
                 tx->key = NULL;
@@ -455,16 +451,34 @@ ieee80211_tx_h_select_key(struct ieee80211_txrx_data *tx)
                  !(tx->flags & IEEE80211_TXRXD_TX_INJECTED)) {
                 I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted);
                 return TXRX_DROP;
-        } else {
+        } else
                 tx->key = NULL;
-                tx->u.tx.control->flags |= IEEE80211_TXCTL_DO_NOT_ENCRYPT;
-        }
 
         if (tx->key) {
+                u16 ftype, stype;
+
                 tx->key->tx_rx_count++;
                 /* TODO: add threshold stuff again */
+
+                switch (tx->key->conf.alg) {
+                case ALG_WEP:
+                        ftype = fc & IEEE80211_FCTL_FTYPE;
+                        stype = fc & IEEE80211_FCTL_STYPE;
+
+                        if (ftype == IEEE80211_FTYPE_MGMT &&
+                            stype == IEEE80211_STYPE_AUTH)
+                                break;
+                case ALG_TKIP:
+                case ALG_CCMP:
+                        if (!WLAN_FC_DATA_PRESENT(fc))
+                                tx->key = NULL;
+                        break;
+                }
         }
 
+        if (!tx->key || !(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
+                tx->u.tx.control->flags |= IEEE80211_TXCTL_DO_NOT_ENCRYPT;
+
         return TXRX_CONTINUE;
 }
 
@@ -706,15 +720,6 @@ ieee80211_tx_h_misc(struct ieee80211_txrx_data *tx)
                 }
         }
 
-        /*
-         * Tell hardware to not encrypt when we had sw crypto.
-         * Because we use the same flag to internally indicate that
-         * no (software) encryption should be done, we have to set it
-         * after all crypto handlers.
-         */
-        if (tx->key && !(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
-                tx->u.tx.control->flags |= IEEE80211_TXCTL_DO_NOT_ENCRYPT;
-
         return TXRX_CONTINUE;
 }
 
diff --git a/net/mac80211/wep.c b/net/mac80211/wep.c
index b5f3413403bd..a0cff72a580b 100644
--- a/net/mac80211/wep.c
+++ b/net/mac80211/wep.c
@@ -349,16 +349,6 @@ static int wep_encrypt_skb(struct ieee80211_txrx_data *tx, struct sk_buff *skb)
 ieee80211_txrx_result
 ieee80211_crypto_wep_encrypt(struct ieee80211_txrx_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;
-
         tx->u.tx.control->iv_len = WEP_IV_LEN;
         tx->u.tx.control->icv_len = WEP_ICV_LEN;
         ieee80211_tx_set_iswep(tx);
diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c
index 20cec1cb956f..6f04311cf0a0 100644
--- a/net/mac80211/wpa.c
+++ b/net/mac80211/wpa.c
@@ -245,16 +245,9 @@ static int tkip_encrypt_skb(struct ieee80211_txrx_data *tx,
 ieee80211_txrx_result
 ieee80211_crypto_tkip_encrypt(struct ieee80211_txrx_data *tx)
 {
-        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;
-        u16 fc;
         struct sk_buff *skb = tx->skb;
         int wpa_test = 0, test = 0;
 
-        fc = le16_to_cpu(hdr->frame_control);
-
-        if (!WLAN_FC_DATA_PRESENT(fc))
-                return TXRX_CONTINUE;
-
         tx->u.tx.control->icv_len = TKIP_ICV_LEN;
         tx->u.tx.control->iv_len = TKIP_IV_LEN;
         ieee80211_tx_set_iswep(tx);
@@ -501,16 +494,9 @@ static int ccmp_encrypt_skb(struct ieee80211_txrx_data *tx,
 ieee80211_txrx_result
 ieee80211_crypto_ccmp_encrypt(struct ieee80211_txrx_data *tx)
 {
-        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;
-        u16 fc;
         struct sk_buff *skb = tx->skb;
         int test = 0;
 
-        fc = le16_to_cpu(hdr->frame_control);
-
-        if (!WLAN_FC_DATA_PRESENT(fc))
-                return TXRX_CONTINUE;
-
         tx->u.tx.control->icv_len = CCMP_MIC_LEN;
         tx->u.tx.control->iv_len = CCMP_HDR_LEN;
         ieee80211_tx_set_iswep(tx);