// 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 wfx_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 wfx_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 wfx_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 wfx_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 wfx_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 wfx_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 wfx_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 wfx_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 wfx_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 wfx_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;
        struct ieee80211_vif *vif = wvif_to_vif(wvif);

        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,
                                                 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 = wfx_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 wfx_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;
}