/*      $OpenBSD: if_urtwn.c,v 1.16 2011/02/10 17:26:40 jakemsr Exp $   */

/*-
 * Copyright (c) 2010 Damien Bergamini <damien.bergamini@free.fr>
 * Copyright (c) 2014 Kevin Lo <kevlo@FreeBSD.org>
 * Copyright (c) 2015-2016 Andriy Voskoboinyk <avos@FreeBSD.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/cdefs.h>
#include "opt_wlan.h"

#include <sys/param.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/mbuf.h>
#include <sys/kernel.h>
#include <sys/socket.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/queue.h>
#include <sys/taskqueue.h>
#include <sys/bus.h>
#include <sys/endian.h>

#include <net/if.h>
#include <net/ethernet.h>
#include <net/if_media.h>

#include <net80211/ieee80211_var.h>
#include <net80211/ieee80211_radiotap.h>

#include <dev/rtwn/if_rtwnreg.h>
#include <dev/rtwn/if_rtwnvar.h>

#include <dev/rtwn/if_rtwn_cam.h>
#include <dev/rtwn/if_rtwn_debug.h>
#include <dev/rtwn/if_rtwn_task.h>

#include <dev/rtwn/rtl8192c/r92c_reg.h>

void
rtwn_init_cam(struct rtwn_softc *sc)
{
        /* Invalidate all CAM entries. */
        rtwn_write_4(sc, R92C_CAMCMD,
            R92C_CAMCMD_POLLING | R92C_CAMCMD_CLR);
}

static int
rtwn_cam_write(struct rtwn_softc *sc, uint32_t addr, uint32_t data)
{
        int error;

        error = rtwn_write_4(sc, R92C_CAMWRITE, data);
        if (error != 0)
                return (error);
        error = rtwn_write_4(sc, R92C_CAMCMD,
            R92C_CAMCMD_POLLING | R92C_CAMCMD_WRITE |
            SM(R92C_CAMCMD_ADDR, addr));

        return (error);
}

void
rtwn_init_seccfg(struct rtwn_softc *sc)
{
        uint16_t seccfg;

        /* Select decryption / encryption flags. */
        seccfg = 0;
        switch (sc->sc_hwcrypto) {
        case RTWN_CRYPTO_SW:
                break;  /* nothing to do */
        case RTWN_CRYPTO_PAIR:
                /* NB: TXUCKEY_DEF / RXUCKEY_DEF are required for RTL8192C */
                seccfg = R92C_SECCFG_TXUCKEY_DEF | R92C_SECCFG_RXUCKEY_DEF |
                    R92C_SECCFG_TXENC_ENA | R92C_SECCFG_RXDEC_ENA |
                    R92C_SECCFG_MC_SRCH_DIS;
                break;
        case RTWN_CRYPTO_FULL:
                seccfg = R92C_SECCFG_TXUCKEY_DEF | R92C_SECCFG_RXUCKEY_DEF |
                    R92C_SECCFG_TXENC_ENA | R92C_SECCFG_RXDEC_ENA |
                    R92C_SECCFG_TXBCKEY_DEF | R92C_SECCFG_RXBCKEY_DEF;
                break;
        default:
                KASSERT(0, ("%s: case %d was not handled\n", __func__,
                    sc->sc_hwcrypto));
                break;
        }

        RTWN_DPRINTF(sc, RTWN_DEBUG_KEY, "%s: seccfg %04X, hwcrypto %d\n",
            __func__, seccfg, sc->sc_hwcrypto);

        rtwn_write_2(sc, R92C_SECCFG, seccfg);
}

int
rtwn_key_alloc(struct ieee80211vap *vap, struct ieee80211_key *k,
    ieee80211_keyix *keyix, ieee80211_keyix *rxkeyix)
{
        struct rtwn_softc *sc = vap->iv_ic->ic_softc;
        int i, start;

        if (ieee80211_is_key_global(vap, k)) {
                *keyix = ieee80211_crypto_get_key_wepidx(vap, k);
                if (sc->sc_hwcrypto != RTWN_CRYPTO_FULL)
                        k->wk_flags |= IEEE80211_KEY_SWCRYPT;
                else {
                        RTWN_LOCK(sc);
                        if (isset(sc->keys_bmap, *keyix)) {
                                device_printf(sc->sc_dev,
                                    "%s: group key slot %d is already used!\n",
                                    __func__, *keyix);
                                /* XXX recover? */
                                RTWN_UNLOCK(sc);
                                return (0);
                        }

                        setbit(sc->keys_bmap, *keyix);
                        RTWN_UNLOCK(sc);
                }

                goto end;
        }

        start = sc->cam_entry_limit;
        switch (sc->sc_hwcrypto) {
        case RTWN_CRYPTO_SW:
                k->wk_flags |= IEEE80211_KEY_SWCRYPT;
                *keyix = 0;
                goto end;
        case RTWN_CRYPTO_PAIR:
                /* all slots for pairwise keys. */
                start = 0;
                RTWN_LOCK(sc);
                if (sc->sc_flags & RTWN_FLAG_CAM_FIXED)
                        start = 4;
                RTWN_UNLOCK(sc);
                break;
        case RTWN_CRYPTO_FULL:
                /* first 4 - for group keys, others for pairwise. */
                start = 4;
                break;
        default:
                KASSERT(0, ("%s: case %d was not handled!\n",
                    __func__, sc->sc_hwcrypto));
                break;
        }

        RTWN_LOCK(sc);
        for (i = start; i < sc->cam_entry_limit; i++) {
                if (isclr(sc->keys_bmap, i)) {
                        setbit(sc->keys_bmap, i);
                        *keyix = i;
                        break;
                }
        }
        RTWN_UNLOCK(sc);
        if (i == sc->cam_entry_limit) {
                /* XXX check and remove keys with the same MAC address */
                k->wk_flags |= IEEE80211_KEY_SWCRYPT;
                *keyix = 0;
        }

end:
        *rxkeyix = *keyix;
        return (1);
}

static int
rtwn_key_set_cb0(struct rtwn_softc *sc, const struct ieee80211_key *k)
{
        uint8_t algo, keyid;
        int i, error;

        if (sc->sc_hwcrypto == RTWN_CRYPTO_FULL &&
            k->wk_keyix < IEEE80211_WEP_NKID)
                keyid = k->wk_keyix;
        else
                keyid = 0;

        /* Map net80211 cipher to HW crypto algorithm. */
        switch (k->wk_cipher->ic_cipher) {
        case IEEE80211_CIPHER_WEP:
                if (k->wk_keylen < 8)
                        algo = R92C_CAM_ALGO_WEP40;
                else
                        algo = R92C_CAM_ALGO_WEP104;
                break;
        case IEEE80211_CIPHER_TKIP:
                algo = R92C_CAM_ALGO_TKIP;
                break;
        case IEEE80211_CIPHER_AES_CCM:
                algo = R92C_CAM_ALGO_AES;
                break;
        default:
                device_printf(sc->sc_dev, "%s: unknown cipher %u\n",
                    __func__, k->wk_cipher->ic_cipher);
                return (EINVAL);
        }

        RTWN_DPRINTF(sc, RTWN_DEBUG_KEY,
            "%s: keyix %u, keyid %u, algo %u/%u, flags %04X, len %u, "
            "macaddr %s\n", __func__, k->wk_keyix, keyid,
            k->wk_cipher->ic_cipher, algo, k->wk_flags, k->wk_keylen,
            ether_sprintf(k->wk_macaddr));

        /* Clear high bits. */
        rtwn_cam_write(sc, R92C_CAM_CTL6(k->wk_keyix), 0);
        rtwn_cam_write(sc, R92C_CAM_CTL7(k->wk_keyix), 0);

        /* Write key. */
        for (i = 0; i < 4; i++) {
                error = rtwn_cam_write(sc, R92C_CAM_KEY(k->wk_keyix, i),
                    le32dec(&k->wk_key[i * 4]));
                if (error != 0)
                        goto fail;
        }

        /* Write CTL0 last since that will validate the CAM entry. */
        error = rtwn_cam_write(sc, R92C_CAM_CTL1(k->wk_keyix),
            le32dec(&k->wk_macaddr[2]));
        if (error != 0)
                goto fail;
        error = rtwn_cam_write(sc, R92C_CAM_CTL0(k->wk_keyix),
            SM(R92C_CAM_ALGO, algo) |
            SM(R92C_CAM_KEYID, keyid) |
            SM(R92C_CAM_MACLO, le16dec(&k->wk_macaddr[0])) |
            R92C_CAM_VALID);
        if (error != 0)
                goto fail;

        return (0);

fail:
        device_printf(sc->sc_dev, "%s fails, error %d\n", __func__, error);
        return (error);
}

static void
rtwn_key_set_cb(struct rtwn_softc *sc, union sec_param *data)
{
        const struct ieee80211_key *k = &data->key;

        (void) rtwn_key_set_cb0(sc, k);
}

int
rtwn_init_static_keys(struct rtwn_softc *sc, struct rtwn_vap *rvp)
{
        int i, error;

        if (sc->sc_hwcrypto != RTWN_CRYPTO_FULL)
                return (0);             /* nothing to do */

        for (i = 0; i < IEEE80211_WEP_NKID; i++) {
                const struct ieee80211_key *k = rvp->keys[i];
                if (k != NULL) {
                        error = rtwn_key_set_cb0(sc, k);
                        if (error != 0)
                                return (error);
                }
        }

        return (0);
}

static void
rtwn_key_del_cb(struct rtwn_softc *sc, union sec_param *data)
{
        struct ieee80211_key *k = &data->key;
        int i;

        RTWN_DPRINTF(sc, RTWN_DEBUG_KEY,
            "%s: keyix %u, flags %04X, macaddr %s\n", __func__,
            k->wk_keyix, k->wk_flags, ether_sprintf(k->wk_macaddr));

        rtwn_cam_write(sc, R92C_CAM_CTL0(k->wk_keyix), 0);
        rtwn_cam_write(sc, R92C_CAM_CTL1(k->wk_keyix), 0);

        /* Clear key. */
        for (i = 0; i < 4; i++)
                rtwn_cam_write(sc, R92C_CAM_KEY(k->wk_keyix, i), 0);
        clrbit(sc->keys_bmap, k->wk_keyix);
}

static int
rtwn_process_key(struct ieee80211vap *vap, const struct ieee80211_key *k,
    int set)
{
        struct rtwn_softc *sc = vap->iv_ic->ic_softc;

        if (k->wk_flags & IEEE80211_KEY_SWCRYPT) {
                /* Not for us. */
                return (1);
        }

        if (ieee80211_is_key_global(vap, k)) {
                if (sc->sc_hwcrypto == RTWN_CRYPTO_FULL) {
                        struct rtwn_vap *rvp = RTWN_VAP(vap);

                        RTWN_LOCK(sc);
                        rvp->keys[k->wk_keyix] = (set ? k : NULL);
                        if ((sc->sc_flags & RTWN_RUNNING) == 0) {
                                if (!set)
                                        clrbit(sc->keys_bmap, k->wk_keyix);
                                RTWN_UNLOCK(sc);
                                return (1);
                        }
                        RTWN_UNLOCK(sc);
                }
        }

        return (!rtwn_cmd_sleepable(sc, k, sizeof(*k),
            set ? rtwn_key_set_cb : rtwn_key_del_cb));
}

int
rtwn_key_set(struct ieee80211vap *vap, const struct ieee80211_key *k)
{
        return (rtwn_process_key(vap, k, 1));
}

int
rtwn_key_delete(struct ieee80211vap *vap, const struct ieee80211_key *k)
{
        return (rtwn_process_key(vap, k, 0));
}