/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "pkcs11.h"

#ifndef DEVM_H

#include "devm.h"

#endif /* DEVM_H */

#ifndef CKHELPER_H

#include "ckhelper.h"

#endif /* CKHELPER_H */

#include "pk11pub.h"

/* measured in seconds */

#define NSSSLOT_TOKEN_DELAY_TIME 1

/* this should track global and per-transaction login information */

#define NSSSLOT_IS_FRIENDLY(slot) \

    (slot->base.flags & NSSSLOT_FLAGS_FRIENDLY)

/* measured as interval */

static PRIntervalTime s_token_delay_time = 0;

NSS_IMPLEMENT PRStatus

nssSlot_Destroy(

    NSSSlot *slot)

{

    if (slot) {

        if (PR_ATOMIC_DECREMENT(&slot->base.refCount) == 0) {

            PK11_FreeSlot(slot->pk11slot);

            PZ_DestroyLock(slot->base.lock);

            PZ_DestroyCondVar(slot->isPresentCondition);

            PZ_DestroyLock(slot->isPresentLock);

            return nssArena_Destroy(slot->base.arena);

        }

    }

    return PR_SUCCESS;

}

void

nssSlot_EnterMonitor(NSSSlot *slot)

{

    if (slot->lock) {

        PZ_Lock(slot->lock);

    }

}

void

nssSlot_ExitMonitor(NSSSlot *slot)

{

    if (slot->lock) {

        PZ_Unlock(slot->lock);

    }

}

NSS_IMPLEMENT void

NSSSlot_Destroy(

    NSSSlot *slot)

{

    (void)nssSlot_Destroy(slot);

}

NSS_IMPLEMENT NSSSlot *

nssSlot_AddRef(

    NSSSlot *slot)

{

    PR_ATOMIC_INCREMENT(&slot->base.refCount);

    return slot;

}

NSS_IMPLEMENT NSSUTF8 *

nssSlot_GetName(

    NSSSlot *slot)

{

    return slot->base.name;

}

NSS_IMPLEMENT NSSUTF8 *

nssSlot_GetTokenName(

    NSSSlot *slot)

{

    return nssToken_GetName(slot->token);

}

NSS_IMPLEMENT void

nssSlot_ResetDelay(

    NSSSlot *slot)

{

    PZ_Lock(slot->isPresentLock);

    slot->lastTokenPingState = nssSlotLastPingState_Reset;

    PZ_Unlock(slot->isPresentLock);

}

static PRBool

token_status_checked(const NSSSlot *slot)

{

    PRIntervalTime time;

    int lastPingState = slot->lastTokenPingState;

    /* When called from the same thread, that means

     * nssSlot_IsTokenPresent() is called recursively through

     * nssSlot_Refresh(). Return immediately in that case. */

    if (slot->isPresentThread == PR_GetCurrentThread()) {

        return PR_TRUE;

    }

    /* Set the delay time for checking the token presence */

    if (s_token_delay_time == 0) {

        s_token_delay_time = PR_SecondsToInterval(NSSSLOT_TOKEN_DELAY_TIME);

    }

    time = PR_IntervalNow();

    if ((lastPingState == nssSlotLastPingState_Valid) && ((time - slot->lastTokenPingTime) < s_token_delay_time)) {

        return PR_TRUE;

    }

    return PR_FALSE;

}

NSS_IMPLEMENT PRBool

nssSlot_IsTokenPresent(

    NSSSlot *slot)

{

    CK_RV ckrv;

    PRStatus nssrv;

    /* XXX */

    nssSession *session;

    CK_SLOT_INFO slotInfo;

    void *epv;

    PRBool isPresent = PR_FALSE;

    /* permanent slots are always present unless they're disabled */

    if (nssSlot_IsPermanent(slot)) {

        return !PK11_IsDisabled(slot->pk11slot);

    }

    /* avoid repeated calls to check token status within set interval */

    PZ_Lock(slot->isPresentLock);

    if (token_status_checked(slot)) {

        CK_FLAGS ckFlags = slot->ckFlags;

        PZ_Unlock(slot->isPresentLock);

        return ((ckFlags & CKF_TOKEN_PRESENT) != 0);

    }

    PZ_Unlock(slot->isPresentLock);

    /* First obtain the slot epv before we set up the condition

     * variable, so we can just return if we couldn't get it. */

    epv = slot->epv;

    if (!epv) {

        return PR_FALSE;

    }

    /* set up condition so only one thread is active in this part of the code at a time */

    PZ_Lock(slot->isPresentLock);

    while (slot->isPresentThread) {

        PR_WaitCondVar(slot->isPresentCondition, PR_INTERVAL_NO_TIMEOUT);

    }

    /* if we were one of multiple threads here, the first thread will have

     * given us the answer, no need to make more queries of the token. */

    if (token_status_checked(slot)) {

        CK_FLAGS ckFlags = slot->ckFlags;

        PZ_Unlock(slot->isPresentLock);

        return ((ckFlags & CKF_TOKEN_PRESENT) != 0);

    }

    /* this is the winning thread, block all others until we've determined

     * if the token is present and that it needs initialization. */

    slot->lastTokenPingState = nssSlotLastPingState_Update;

    slot->isPresentThread = PR_GetCurrentThread();

    PZ_Unlock(slot->isPresentLock);

    nssSlot_EnterMonitor(slot);

    ckrv = CKAPI(epv)->C_GetSlotInfo(slot->slotID, &slotInfo);

    nssSlot_ExitMonitor(slot);

    if (ckrv != CKR_OK) {

        slot->token->base.name[0] = 0; /* XXX */

        isPresent = PR_FALSE;

        goto done;

    }

    slot->ckFlags = slotInfo.flags;

    /* check for the presence of the token */

    if ((slot->ckFlags & CKF_TOKEN_PRESENT) == 0) {

        if (!slot->token) {

            /* token was never present */

            isPresent = PR_FALSE;

            goto done;

        }

        session = nssToken_GetDefaultSession(slot->token);

        if (session) {

            nssSession_EnterMonitor(session);

            /* token is not present */

            if (session->handle != CK_INVALID_SESSION) {

                /* session is valid, close and invalidate it */

                CKAPI(epv)

                    ->C_CloseSession(session->handle);

                session->handle = CK_INVALID_SESSION;

            }

            nssSession_ExitMonitor(session);

        }

        if (slot->token->base.name[0] != 0) {

            /* notify the high-level cache that the token is removed */

            slot->token->base.name[0] = 0; /* XXX */

            nssToken_NotifyCertsNotVisible(slot->token);

        }

        slot->token->base.name[0] = 0; /* XXX */

        /* clear the token cache */

        nssToken_Remove(slot->token);

        isPresent = PR_FALSE;

        goto done;

    }

    /* token is present, use the session info to determine if the card

     * has been removed and reinserted.

     */

    session = nssToken_GetDefaultSession(slot->token);

    if (session) {

        PRBool tokenRemoved;

        nssSession_EnterMonitor(session);

        if (session->handle != CK_INVALID_SESSION) {

            CK_SESSION_INFO sessionInfo;

            ckrv = CKAPI(epv)->C_GetSessionInfo(session->handle, &sessionInfo);

            if (ckrv != CKR_OK) {

                /* session is screwy, close and invalidate it */

                CKAPI(epv)

                    ->C_CloseSession(session->handle);

                session->handle = CK_INVALID_SESSION;

            }

        }

        tokenRemoved = (session->handle == CK_INVALID_SESSION);

        nssSession_ExitMonitor(session);

        /* token not removed, finished */

        if (!tokenRemoved) {

            isPresent = PR_TRUE;

            goto done;

        }

    }

    /* the token has been removed, and reinserted, or the slot contains

     * a token it doesn't recognize. invalidate all the old

     * information we had on this token, if we can't refresh, clear

     * the present flag */

    nssToken_NotifyCertsNotVisible(slot->token);

    nssToken_Remove(slot->token);

    /* token has been removed, need to refresh with new session */

    nssrv = nssSlot_Refresh(slot);

    isPresent = PR_TRUE;

    if (nssrv != PR_SUCCESS) {

        slot->token->base.name[0] = 0; /* XXX */

        slot->ckFlags &= ~CKF_TOKEN_PRESENT;

        isPresent = PR_FALSE;

    }

done:

    /* Once we've set up the condition variable,

     * Before returning, it's necessary to:

     *  1) Set the lastTokenPingTime so that any other threads waiting on this

     *     initialization and any future calls within the initialization window

     *     return the just-computed status.

     *  2) Indicate we're complete, waking up all other threads that may still

     *     be waiting on initialization can progress.

     */

    PZ_Lock(slot->isPresentLock);

    /* don't update the time if we were reset while we were

     * getting the token state */

    if (slot->lastTokenPingState == nssSlotLastPingState_Update) {

        slot->lastTokenPingTime = PR_IntervalNow();

        slot->lastTokenPingState = nssSlotLastPingState_Valid;

    }

    slot->isPresentThread = NULL;

    PR_NotifyAllCondVar(slot->isPresentCondition);

    PZ_Unlock(slot->isPresentLock);

    return isPresent;

}

NSS_IMPLEMENT void *

nssSlot_GetCryptokiEPV(

    NSSSlot *slot)

{

    return slot->epv;

}

NSS_IMPLEMENT NSSToken *

nssSlot_GetToken(

    NSSSlot *slot)

{

    NSSToken *rvToken = NULL;

    if (nssSlot_IsTokenPresent(slot)) {

        /* Even if a token should be present, check `slot->token` too as it

         * might be gone already. This would happen mostly on shutdown. */

        nssSlot_EnterMonitor(slot);

        if (slot->token)

            rvToken = nssToken_AddRef(slot->token);

        nssSlot_ExitMonitor(slot);

    }

    return rvToken;

}

NSS_IMPLEMENT PRStatus

nssSession_EnterMonitor(

    nssSession *s)

{

    if (s->lock)

        PZ_Lock(s->lock);

    return PR_SUCCESS;

}

NSS_IMPLEMENT PRStatus

nssSession_ExitMonitor(

    nssSession *s)

{

    return (s->lock) ? PZ_Unlock(s->lock) : PR_SUCCESS;

}

NSS_EXTERN PRBool

nssSession_IsReadWrite(

    nssSession *s)

{

    return s->isRW;

}