[PATCH wireless-next v2 3/6] wifi: ath11k: Use michael_mic() from cfg80211

[Eric Biggers <ebiggers@kernel.org>]

Just use the michael_mic() function from cfg80211 instead of a local
implementation of it using the crypto_shash API.

Note: when the kernel is booted with fips=1,
crypto_alloc_shash("michael_mic", 0, 0) always returned
ERR_PTR(-ENOENT), because Michael MIC is not a "FIPS allowed" algorithm.
For now, just preserve that behavior exactly, to ensure that TKIP is not
allowed to be used in FIPS mode.  This logic actually seems to disable
the entire driver in FIPS mode and not just TKIP, but that was the
existing behavior.  Supporting this driver in FIPS mode, if anyone
actually needs it there, should be a separate commit.

Signed-off-by: Eric Biggers <ebiggers@kernel.org>
---
 drivers/net/wireless/ath/ath11k/Kconfig |  1 -
 drivers/net/wireless/ath/ath11k/dp.c    |  2 -
 drivers/net/wireless/ath/ath11k/dp_rx.c | 60 +++----------------------
 drivers/net/wireless/ath/ath11k/peer.h  |  1 -
 4 files changed, 7 insertions(+), 57 deletions(-)

diff --git a/drivers/net/wireless/ath/ath11k/Kconfig b/drivers/net/wireless/ath/ath11k/Kconfig
index 47dfd39caa89a..385513cfdc30e 100644
--- a/drivers/net/wireless/ath/ath11k/Kconfig
+++ b/drivers/net/wireless/ath/ath11k/Kconfig
@@ -1,10 +1,9 @@
 # SPDX-License-Identifier: BSD-3-Clause-Clear
 config ATH11K
 	tristate "Qualcomm Technologies 802.11ax chipset support"
 	depends on MAC80211 && HAS_DMA
-	select CRYPTO_MICHAEL_MIC
 	select ATH_COMMON
 	select QCOM_QMI_HELPERS
 	help
 	  This module adds support for Qualcomm Technologies 802.11ax family of
 	  chipsets.
diff --git a/drivers/net/wireless/ath/ath11k/dp.c b/drivers/net/wireless/ath/ath11k/dp.c
index c940de285276d..bbb86f1651419 100644
--- a/drivers/net/wireless/ath/ath11k/dp.c
+++ b/drivers/net/wireless/ath/ath11k/dp.c
@@ -3,11 +3,10 @@
  * Copyright (c) 2018-2019 The Linux Foundation. All rights reserved.
  * Copyright (c) 2021-2025 Qualcomm Innovation Center, Inc. All rights reserved.
  * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
  */
 
-#include <crypto/hash.h>
 #include <linux/export.h>
 #include "core.h"
 #include "dp_tx.h"
 #include "hal_tx.h"
 #include "hif.h"
@@ -37,11 +36,10 @@ void ath11k_dp_peer_cleanup(struct ath11k *ar, int vdev_id, const u8 *addr)
 		return;
 	}
 
 	ath11k_peer_rx_tid_cleanup(ar, peer);
 	peer->dp_setup_done = false;
-	crypto_free_shash(peer->tfm_mmic);
 	spin_unlock_bh(&ab->base_lock);
 }
 
 int ath11k_dp_peer_setup(struct ath11k *ar, int vdev_id, const u8 *addr)
 {
diff --git a/drivers/net/wireless/ath/ath11k/dp_rx.c b/drivers/net/wireless/ath/ath11k/dp_rx.c
index 85defe11750d5..fe79109adc705 100644
--- a/drivers/net/wireless/ath/ath11k/dp_rx.c
+++ b/drivers/net/wireless/ath/ath11k/dp_rx.c
@@ -2,14 +2,14 @@
 /*
  * Copyright (c) 2018-2019 The Linux Foundation. All rights reserved.
  * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
  */
 
+#include <linux/fips.h>
 #include <linux/ieee80211.h>
 #include <linux/kernel.h>
 #include <linux/skbuff.h>
-#include <crypto/hash.h>
 #include "core.h"
 #include "debug.h"
 #include "debugfs_htt_stats.h"
 #include "debugfs_sta.h"
 #include "hal_desc.h"
@@ -3180,96 +3180,50 @@ static void ath11k_dp_rx_frag_timer(struct timer_list *timer)
 }
 
 int ath11k_peer_rx_frag_setup(struct ath11k *ar, const u8 *peer_mac, int vdev_id)
 {
 	struct ath11k_base *ab = ar->ab;
-	struct crypto_shash *tfm;
 	struct ath11k_peer *peer;
 	struct dp_rx_tid *rx_tid;
 	int i;
 
-	tfm = crypto_alloc_shash("michael_mic", 0, 0);
-	if (IS_ERR(tfm)) {
-		ath11k_warn(ab, "failed to allocate michael_mic shash: %ld\n",
-			    PTR_ERR(tfm));
-		return PTR_ERR(tfm);
+	if (fips_enabled) {
+		ath11k_warn(ab, "This driver is disabled due to FIPS\n");
+		return -ENOENT;
 	}
 
 	spin_lock_bh(&ab->base_lock);
 
 	peer = ath11k_peer_find(ab, vdev_id, peer_mac);
 	if (!peer) {
 		ath11k_warn(ab, "failed to find the peer to set up fragment info\n");
 		spin_unlock_bh(&ab->base_lock);
-		crypto_free_shash(tfm);
 		return -ENOENT;
 	}
 
 	for (i = 0; i <= IEEE80211_NUM_TIDS; i++) {
 		rx_tid = &peer->rx_tid[i];
 		rx_tid->ab = ab;
 		timer_setup(&rx_tid->frag_timer, ath11k_dp_rx_frag_timer, 0);
 		skb_queue_head_init(&rx_tid->rx_frags);
 	}
 
-	peer->tfm_mmic = tfm;
 	peer->dp_setup_done = true;
 	spin_unlock_bh(&ab->base_lock);
 
 	return 0;
 }
 
-static int ath11k_dp_rx_h_michael_mic(struct crypto_shash *tfm, u8 *key,
-				      struct ieee80211_hdr *hdr, u8 *data,
-				      size_t data_len, u8 *mic)
-{
-	SHASH_DESC_ON_STACK(desc, tfm);
-	u8 mic_hdr[16] = {};
-	u8 tid = 0;
-	int ret;
-
-	if (!tfm)
-		return -EINVAL;
-
-	desc->tfm = tfm;
-
-	ret = crypto_shash_setkey(tfm, key, 8);
-	if (ret)
-		goto out;
-
-	ret = crypto_shash_init(desc);
-	if (ret)
-		goto out;
-
-	/* TKIP MIC header */
-	memcpy(mic_hdr, ieee80211_get_DA(hdr), ETH_ALEN);
-	memcpy(mic_hdr + ETH_ALEN, ieee80211_get_SA(hdr), ETH_ALEN);
-	if (ieee80211_is_data_qos(hdr->frame_control))
-		tid = ieee80211_get_tid(hdr);
-	mic_hdr[12] = tid;
-
-	ret = crypto_shash_update(desc, mic_hdr, 16);
-	if (ret)
-		goto out;
-	ret = crypto_shash_update(desc, data, data_len);
-	if (ret)
-		goto out;
-	ret = crypto_shash_final(desc, mic);
-out:
-	shash_desc_zero(desc);
-	return ret;
-}
-
 static int ath11k_dp_rx_h_verify_tkip_mic(struct ath11k *ar, struct ath11k_peer *peer,
 					  struct sk_buff *msdu)
 {
 	struct hal_rx_desc *rx_desc = (struct hal_rx_desc *)msdu->data;
 	struct ieee80211_rx_status *rxs = IEEE80211_SKB_RXCB(msdu);
 	struct ieee80211_key_conf *key_conf;
 	struct ieee80211_hdr *hdr;
 	u8 mic[IEEE80211_CCMP_MIC_LEN];
-	int head_len, tail_len, ret;
+	int head_len, tail_len;
 	size_t data_len;
 	u32 hdr_len, hal_rx_desc_sz = ar->ab->hw_params.hal_desc_sz;
 	u8 *key, *data;
 	u8 key_idx;
 
@@ -3291,12 +3245,12 @@ static int ath11k_dp_rx_h_verify_tkip_mic(struct ath11k *ar, struct ath11k_peer
 
 	data = msdu->data + head_len;
 	data_len = msdu->len - head_len - tail_len;
 	key = &key_conf->key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY];
 
-	ret = ath11k_dp_rx_h_michael_mic(peer->tfm_mmic, key, hdr, data, data_len, mic);
-	if (ret || memcmp(mic, data + data_len, IEEE80211_CCMP_MIC_LEN))
+	michael_mic(key, hdr, data, data_len, mic);
+	if (memcmp(mic, data + data_len, IEEE80211_CCMP_MIC_LEN))
 		goto mic_fail;
 
 	return 0;
 
 mic_fail:
diff --git a/drivers/net/wireless/ath/ath11k/peer.h b/drivers/net/wireless/ath/ath11k/peer.h
index 3ad2f3355b14f..f5ef1a27f8f25 100644
--- a/drivers/net/wireless/ath/ath11k/peer.h
+++ b/drivers/net/wireless/ath/ath11k/peer.h
@@ -27,11 +27,10 @@ struct ath11k_peer {
 	struct rhash_head rhash_addr;
 
 	/* Info used in MMIC verification of
 	 * RX fragments
 	 */
-	struct crypto_shash *tfm_mmic;
 	u8 mcast_keyidx;
 	u8 ucast_keyidx;
 	u16 sec_type;
 	u16 sec_type_grp;
 	bool is_authorized;
-- 
2.53.0