mac80211: move TKIP TX IVs to public part of key struct

Some drivers/devices might want to set the IVs by
themselves (and still let mac80211 generate MMIC).

Specifically, this is needed when the device does
offloading at certain times, and the driver has
to make sure that the IVs of new tx frames (from
the host) are synchronized with IVs that were
potentially used during the offloading.

Similarly to CCMP, move the TX IVs of TKIP keys to the
public part of the key struct, and export a function
to add the IV right into the crypto header.

The public tx_pn field is defined as atomic64, so define
TKIP_PN_TO_IV16/32 helper macros to convert it to iv16/32
when needed.

Since the iv32 used for the p1k cache is taken
directly from the frame, we can safely remove
iv16/32 from being protected by tkip.txlock.

Signed-off-by: Eliad Peller <eliadx.peller@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 18 insertions, 18 deletions

diff --git a/net/mac80211/tkip.c b/net/mac80211/tkip.c
index 0ae207771a58..b3622823bad2 100644
--- a/net/mac80211/tkip.c
+++ b/net/mac80211/tkip.c
@@ -1,6 +1,7 @@
 /*
  * Copyright 2002-2004, Instant802 Networks, Inc.
  * Copyright 2005, Devicescape Software, Inc.
+ * Copyright (C) 2016 Intel Deutschland GmbH
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -142,15 +143,14 @@ static void tkip_mixing_phase2(const u8 *tk, struct tkip_ctx *ctx,
 /* Add TKIP IV and Ext. IV at @pos. @iv0, @iv1, and @iv2 are the first octets
  * of the IV. Returns pointer to the octet following IVs (i.e., beginning of
  * the packet payload). */
-u8 *ieee80211_tkip_add_iv(u8 *pos, struct ieee80211_key *key)
+u8 *ieee80211_tkip_add_iv(u8 *pos, struct ieee80211_key_conf *keyconf, u64 pn)
 {
-	lockdep_assert_held(&key->u.tkip.txlock);
-
-	pos = write_tkip_iv(pos, key->u.tkip.tx.iv16);
-	*pos++ = (key->conf.keyidx << 6) | (1 << 5) /* Ext IV */;
-	put_unaligned_le32(key->u.tkip.tx.iv32, pos);
+	pos = write_tkip_iv(pos, TKIP_PN_TO_IV16(pn));
+	*pos++ = (keyconf->keyidx << 6) | (1 << 5) /* Ext IV */;
+	put_unaligned_le32(TKIP_PN_TO_IV32(pn), pos);
 	return pos + 4;
 }
+EXPORT_SYMBOL_GPL(ieee80211_tkip_add_iv);
 
 static void ieee80211_compute_tkip_p1k(struct ieee80211_key *key, u32 iv32)
 {
@@ -250,6 +250,7 @@ int ieee80211_tkip_decrypt_data(struct crypto_cipher *tfm,
 	u8 rc4key[16], keyid, *pos = payload;
 	int res;
 	const u8 *tk = &key->conf.key[NL80211_TKIP_DATA_OFFSET_ENCR_KEY];
+	struct tkip_ctx_rx *rx_ctx = &key->u.tkip.rx[queue];
 
 	if (payload_len < 12)
 		return -1;
@@ -265,37 +266,36 @@ int ieee80211_tkip_decrypt_data(struct crypto_cipher *tfm,
 	if ((keyid >> 6) != key->conf.keyidx)
 		return TKIP_DECRYPT_INVALID_KEYIDX;
 
-	if (key->u.tkip.rx[queue].state != TKIP_STATE_NOT_INIT &&
-	    (iv32 < key->u.tkip.rx[queue].iv32 ||
-	     (iv32 == key->u.tkip.rx[queue].iv32 &&
-	      iv16 <= key->u.tkip.rx[queue].iv16)))
+	if (rx_ctx->ctx.state != TKIP_STATE_NOT_INIT &&
+	    (iv32 < rx_ctx->iv32 ||
+	     (iv32 == rx_ctx->iv32 && iv16 <= rx_ctx->iv16)))
 		return TKIP_DECRYPT_REPLAY;
 
 	if (only_iv) {
 		res = TKIP_DECRYPT_OK;
-		key->u.tkip.rx[queue].state = TKIP_STATE_PHASE1_HW_UPLOADED;
+		rx_ctx->ctx.state = TKIP_STATE_PHASE1_HW_UPLOADED;
 		goto done;
 	}
 
-	if (key->u.tkip.rx[queue].state == TKIP_STATE_NOT_INIT ||
-	    key->u.tkip.rx[queue].iv32 != iv32) {
+	if (rx_ctx->ctx.state == TKIP_STATE_NOT_INIT ||
+	    rx_ctx->iv32 != iv32) {
 		/* IV16 wrapped around - perform TKIP phase 1 */
-		tkip_mixing_phase1(tk, &key->u.tkip.rx[queue], ta, iv32);
+		tkip_mixing_phase1(tk, &rx_ctx->ctx, ta, iv32);
 	}
 	if (key->local->ops->update_tkip_key &&
 	    key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE &&
-	    key->u.tkip.rx[queue].state != TKIP_STATE_PHASE1_HW_UPLOADED) {
+	    rx_ctx->ctx.state != TKIP_STATE_PHASE1_HW_UPLOADED) {
 		struct ieee80211_sub_if_data *sdata = key->sdata;
 
 		if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
 			sdata = container_of(key->sdata->bss,
 					struct ieee80211_sub_if_data, u.ap);
 		drv_update_tkip_key(key->local, sdata, &key->conf, key->sta,
-				iv32, key->u.tkip.rx[queue].p1k);
-		key->u.tkip.rx[queue].state = TKIP_STATE_PHASE1_HW_UPLOADED;
+				iv32, rx_ctx->ctx.p1k);
+		rx_ctx->ctx.state = TKIP_STATE_PHASE1_HW_UPLOADED;
 	}
 
-	tkip_mixing_phase2(tk, &key->u.tkip.rx[queue], iv16, rc4key);
+	tkip_mixing_phase2(tk, &rx_ctx->ctx, iv16, rc4key);
 
 	res = ieee80211_wep_decrypt_data(tfm, rc4key, 16, pos, payload_len - 12);
  done: