[PATCH v2 14/24] wfx: add key.c/key.h

[Jerome Pouiller <Jerome.Pouiller@silabs.com>]

From: Jérôme Pouiller <jerome.pouiller@silabs.com>

Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
---
 drivers/net/wireless/silabs/wfx/key.c | 241 ++++++++++++++++++++++++++
 drivers/net/wireless/silabs/wfx/key.h |  20 +++
 2 files changed, 261 insertions(+)
 create mode 100644 drivers/net/wireless/silabs/wfx/key.c
 create mode 100644 drivers/net/wireless/silabs/wfx/key.h

diff --git a/drivers/net/wireless/silabs/wfx/key.c b/drivers/net/wireless/silabs/wfx/key.c
new file mode 100644
index 000000000000..2ab82bed4c1b
--- /dev/null
+++ b/drivers/net/wireless/silabs/wfx/key.c
@@ -0,0 +1,241 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Key management related functions.
+ *
+ * Copyright (c) 2017-2020, Silicon Laboratories, Inc.
+ * Copyright (c) 2010, ST-Ericsson
+ */
+#include <linux/etherdevice.h>
+#include <net/mac80211.h>
+
+#include "key.h"
+#include "wfx.h"
+#include "hif_tx_mib.h"
+
+static int wfx_alloc_key(struct wfx_dev *wdev)
+{
+	int idx;
+
+	idx = ffs(~wdev->key_map) - 1;
+	if (idx < 0 || idx >= MAX_KEY_ENTRIES)
+		return -1;
+
+	wdev->key_map |= BIT(idx);
+	return idx;
+}
+
+static void wfx_free_key(struct wfx_dev *wdev, int idx)
+{
+	WARN(!(wdev->key_map & BIT(idx)), "inconsistent key allocation");
+	wdev->key_map &= ~BIT(idx);
+}
+
+static u8 fill_wep_pair(struct hif_wep_pairwise_key *msg,
+			     struct ieee80211_key_conf *key, u8 *peer_addr)
+{
+	WARN(key->keylen > sizeof(msg->key_data), "inconsistent data");
+	msg->key_length = key->keylen;
+	memcpy(msg->key_data, key->key, key->keylen);
+	ether_addr_copy(msg->peer_address, peer_addr);
+	return HIF_KEY_TYPE_WEP_PAIRWISE;
+}
+
+static u8 fill_wep_group(struct hif_wep_group_key *msg,
+			      struct ieee80211_key_conf *key)
+{
+	WARN(key->keylen > sizeof(msg->key_data), "inconsistent data");
+	msg->key_id = key->keyidx;
+	msg->key_length = key->keylen;
+	memcpy(msg->key_data, key->key, key->keylen);
+	return HIF_KEY_TYPE_WEP_DEFAULT;
+}
+
+static u8 fill_tkip_pair(struct hif_tkip_pairwise_key *msg,
+			      struct ieee80211_key_conf *key, u8 *peer_addr)
+{
+	u8 *keybuf = key->key;
+
+	WARN(key->keylen != sizeof(msg->tkip_key_data)
+			    + sizeof(msg->tx_mic_key)
+			    + sizeof(msg->rx_mic_key), "inconsistent data");
+	memcpy(msg->tkip_key_data, keybuf, sizeof(msg->tkip_key_data));
+	keybuf += sizeof(msg->tkip_key_data);
+	memcpy(msg->tx_mic_key, keybuf, sizeof(msg->tx_mic_key));
+	keybuf += sizeof(msg->tx_mic_key);
+	memcpy(msg->rx_mic_key, keybuf, sizeof(msg->rx_mic_key));
+	ether_addr_copy(msg->peer_address, peer_addr);
+	return HIF_KEY_TYPE_TKIP_PAIRWISE;
+}
+
+static u8 fill_tkip_group(struct hif_tkip_group_key *msg,
+			       struct ieee80211_key_conf *key,
+			       struct ieee80211_key_seq *seq,
+			       enum nl80211_iftype iftype)
+{
+	u8 *keybuf = key->key;
+
+	WARN(key->keylen != sizeof(msg->tkip_key_data)
+			    + 2 * sizeof(msg->rx_mic_key), "inconsistent data");
+	msg->key_id = key->keyidx;
+	memcpy(msg->rx_sequence_counter,
+	       &seq->tkip.iv16, sizeof(seq->tkip.iv16));
+	memcpy(msg->rx_sequence_counter + sizeof(u16),
+	       &seq->tkip.iv32, sizeof(seq->tkip.iv32));
+	memcpy(msg->tkip_key_data, keybuf, sizeof(msg->tkip_key_data));
+	keybuf += sizeof(msg->tkip_key_data);
+	if (iftype == NL80211_IFTYPE_AP)
+		// Use Tx MIC Key
+		memcpy(msg->rx_mic_key, keybuf + 0, sizeof(msg->rx_mic_key));
+	else
+		// Use Rx MIC Key
+		memcpy(msg->rx_mic_key, keybuf + 8, sizeof(msg->rx_mic_key));
+	return HIF_KEY_TYPE_TKIP_GROUP;
+}
+
+static u8 fill_ccmp_pair(struct hif_aes_pairwise_key *msg,
+			      struct ieee80211_key_conf *key, u8 *peer_addr)
+{
+	WARN(key->keylen != sizeof(msg->aes_key_data), "inconsistent data");
+	ether_addr_copy(msg->peer_address, peer_addr);
+	memcpy(msg->aes_key_data, key->key, key->keylen);
+	return HIF_KEY_TYPE_AES_PAIRWISE;
+}
+
+static u8 fill_ccmp_group(struct hif_aes_group_key *msg,
+			       struct ieee80211_key_conf *key,
+			       struct ieee80211_key_seq *seq)
+{
+	WARN(key->keylen != sizeof(msg->aes_key_data), "inconsistent data");
+	memcpy(msg->aes_key_data, key->key, key->keylen);
+	memcpy(msg->rx_sequence_counter, seq->ccmp.pn, sizeof(seq->ccmp.pn));
+	memreverse(msg->rx_sequence_counter, sizeof(seq->ccmp.pn));
+	msg->key_id = key->keyidx;
+	return HIF_KEY_TYPE_AES_GROUP;
+}
+
+static u8 fill_sms4_pair(struct hif_wapi_pairwise_key *msg,
+			      struct ieee80211_key_conf *key, u8 *peer_addr)
+{
+	u8 *keybuf = key->key;
+
+	WARN(key->keylen != sizeof(msg->wapi_key_data)
+			    + sizeof(msg->mic_key_data), "inconsistent data");
+	ether_addr_copy(msg->peer_address, peer_addr);
+	memcpy(msg->wapi_key_data, keybuf, sizeof(msg->wapi_key_data));
+	keybuf += sizeof(msg->wapi_key_data);
+	memcpy(msg->mic_key_data, keybuf, sizeof(msg->mic_key_data));
+	msg->key_id = key->keyidx;
+	return HIF_KEY_TYPE_WAPI_PAIRWISE;
+}
+
+static u8 fill_sms4_group(struct hif_wapi_group_key *msg,
+			       struct ieee80211_key_conf *key)
+{
+	u8 *keybuf = key->key;
+
+	WARN(key->keylen != sizeof(msg->wapi_key_data)
+			    + sizeof(msg->mic_key_data), "inconsistent data");
+	memcpy(msg->wapi_key_data, keybuf, sizeof(msg->wapi_key_data));
+	keybuf += sizeof(msg->wapi_key_data);
+	memcpy(msg->mic_key_data, keybuf, sizeof(msg->mic_key_data));
+	msg->key_id = key->keyidx;
+	return HIF_KEY_TYPE_WAPI_GROUP;
+}
+
+static u8 fill_aes_cmac_group(struct hif_igtk_group_key *msg,
+				   struct ieee80211_key_conf *key,
+				   struct ieee80211_key_seq *seq)
+{
+	WARN(key->keylen != sizeof(msg->igtk_key_data), "inconsistent data");
+	memcpy(msg->igtk_key_data, key->key, key->keylen);
+	memcpy(msg->ipn, seq->aes_cmac.pn, sizeof(seq->aes_cmac.pn));
+	memreverse(msg->ipn, sizeof(seq->aes_cmac.pn));
+	msg->key_id = key->keyidx;
+	return HIF_KEY_TYPE_IGTK_GROUP;
+}
+
+static int wfx_add_key(struct wfx_vif *wvif, struct ieee80211_sta *sta,
+		       struct ieee80211_key_conf *key)
+{
+	int ret;
+	struct hif_req_add_key k = { };
+	struct ieee80211_key_seq seq;
+	struct wfx_dev *wdev = wvif->wdev;
+	int idx = wfx_alloc_key(wvif->wdev);
+	bool pairwise = key->flags & IEEE80211_KEY_FLAG_PAIRWISE;
+
+	WARN(key->flags & IEEE80211_KEY_FLAG_PAIRWISE && !sta, "inconsistent data");
+	ieee80211_get_key_rx_seq(key, 0, &seq);
+	if (idx < 0)
+		return -EINVAL;
+	k.int_id = wvif->id;
+	k.entry_index = idx;
+	if (key->cipher == WLAN_CIPHER_SUITE_WEP40 ||
+	    key->cipher == WLAN_CIPHER_SUITE_WEP104) {
+		if (pairwise)
+			k.type = fill_wep_pair(&k.key.wep_pairwise_key, key,
+					       sta->addr);
+		else
+			k.type = fill_wep_group(&k.key.wep_group_key, key);
+	} else if (key->cipher == WLAN_CIPHER_SUITE_TKIP) {
+		if (pairwise)
+			k.type = fill_tkip_pair(&k.key.tkip_pairwise_key, key,
+						sta->addr);
+		else
+			k.type = fill_tkip_group(&k.key.tkip_group_key, key,
+						 &seq, wvif->vif->type);
+	} else if (key->cipher == WLAN_CIPHER_SUITE_CCMP) {
+		if (pairwise)
+			k.type = fill_ccmp_pair(&k.key.aes_pairwise_key, key,
+						sta->addr);
+		else
+			k.type = fill_ccmp_group(&k.key.aes_group_key, key,
+						 &seq);
+	} else if (key->cipher == WLAN_CIPHER_SUITE_SMS4) {
+		if (pairwise)
+			k.type = fill_sms4_pair(&k.key.wapi_pairwise_key, key,
+						sta->addr);
+		else
+			k.type = fill_sms4_group(&k.key.wapi_group_key, key);
+	} else if (key->cipher == WLAN_CIPHER_SUITE_AES_CMAC) {
+		k.type = fill_aes_cmac_group(&k.key.igtk_group_key, key, &seq);
+		key->flags |= IEEE80211_KEY_FLAG_GENERATE_MMIE;
+	} else {
+		dev_warn(wdev->dev, "unsupported key type %d\n", key->cipher);
+		wfx_free_key(wdev, idx);
+		return -EOPNOTSUPP;
+	}
+	ret = hif_add_key(wdev, &k);
+	if (ret) {
+		wfx_free_key(wdev, idx);
+		return -EOPNOTSUPP;
+	}
+	key->flags |= IEEE80211_KEY_FLAG_PUT_IV_SPACE |
+		      IEEE80211_KEY_FLAG_RESERVE_TAILROOM;
+	key->hw_key_idx = idx;
+	return 0;
+}
+
+static int wfx_remove_key(struct wfx_vif *wvif, struct ieee80211_key_conf *key)
+{
+	WARN(key->hw_key_idx >= MAX_KEY_ENTRIES, "corrupted hw_key_idx");
+	wfx_free_key(wvif->wdev, key->hw_key_idx);
+	return hif_remove_key(wvif->wdev, key->hw_key_idx);
+}
+
+int wfx_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
+		struct ieee80211_vif *vif, struct ieee80211_sta *sta,
+		struct ieee80211_key_conf *key)
+{
+	int ret = -EOPNOTSUPP;
+	struct wfx_vif *wvif = (struct wfx_vif *)vif->drv_priv;
+
+	mutex_lock(&wvif->wdev->conf_mutex);
+	if (cmd == SET_KEY)
+		ret = wfx_add_key(wvif, sta, key);
+	if (cmd == DISABLE_KEY)
+		ret = wfx_remove_key(wvif, key);
+	mutex_unlock(&wvif->wdev->conf_mutex);
+	return ret;
+}
+
diff --git a/drivers/net/wireless/silabs/wfx/key.h b/drivers/net/wireless/silabs/wfx/key.h
new file mode 100644
index 000000000000..70a44d0ca35e
--- /dev/null
+++ b/drivers/net/wireless/silabs/wfx/key.h
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Implementation of mac80211 API.
+ *
+ * Copyright (c) 2017-2020, Silicon Laboratories, Inc.
+ * Copyright (c) 2010, ST-Ericsson
+ */
+#ifndef WFX_KEY_H
+#define WFX_KEY_H
+
+#include <net/mac80211.h>
+
+struct wfx_dev;
+struct wfx_vif;
+
+int wfx_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
+		struct ieee80211_vif *vif, struct ieee80211_sta *sta,
+		struct ieee80211_key_conf *key);
+
+#endif /* WFX_STA_H */
-- 
2.28.0