tor-browser

The Tor Browser
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devslot.c (9265B)


      1 /* This Source Code Form is subject to the terms of the Mozilla Public
      2 * License, v. 2.0. If a copy of the MPL was not distributed with this
      3 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
      4 
      5 #include "pkcs11.h"
      6 
      7 #ifndef DEVM_H
      8 #include "devm.h"
      9 #endif /* DEVM_H */
     10 
     11 #ifndef CKHELPER_H
     12 #include "ckhelper.h"
     13 #endif /* CKHELPER_H */
     14 
     15 #include "pkim.h"
     16 #include "dev3hack.h"
     17 #include "pk11func.h"
     18 
     19 /* measured in seconds */
     20 #define NSSSLOT_TOKEN_DELAY_TIME 1
     21 
     22 /* this should track global and per-transaction login information */
     23 
     24 #define NSSSLOT_IS_FRIENDLY(slot) \
     25    (slot->base.flags & NSSSLOT_FLAGS_FRIENDLY)
     26 
     27 /* measured as interval */
     28 static PRIntervalTime s_token_delay_time = 0;
     29 
     30 NSS_IMPLEMENT PRStatus
     31 nssSlot_Destroy(
     32    NSSSlot *slot)
     33 {
     34    if (slot) {
     35        if (PR_ATOMIC_DECREMENT(&slot->base.refCount) == 0) {
     36            PK11_FreeSlot(slot->pk11slot);
     37            PZ_DestroyLock(slot->base.lock);
     38            PZ_DestroyCondVar(slot->isPresentCondition);
     39            PZ_DestroyLock(slot->isPresentLock);
     40            return nssArena_Destroy(slot->base.arena);
     41        }
     42    }
     43    return PR_SUCCESS;
     44 }
     45 
     46 void
     47 nssSlot_EnterMonitor(NSSSlot *slot)
     48 {
     49    if (slot->lock) {
     50        PZ_Lock(slot->lock);
     51    }
     52 }
     53 
     54 void
     55 nssSlot_ExitMonitor(NSSSlot *slot)
     56 {
     57    if (slot->lock) {
     58        PZ_Unlock(slot->lock);
     59    }
     60 }
     61 
     62 NSS_IMPLEMENT void
     63 NSSSlot_Destroy(
     64    NSSSlot *slot)
     65 {
     66    (void)nssSlot_Destroy(slot);
     67 }
     68 
     69 NSS_IMPLEMENT NSSSlot *
     70 nssSlot_AddRef(
     71    NSSSlot *slot)
     72 {
     73    PR_ATOMIC_INCREMENT(&slot->base.refCount);
     74    return slot;
     75 }
     76 
     77 NSS_IMPLEMENT NSSUTF8 *
     78 nssSlot_GetName(
     79    NSSSlot *slot)
     80 {
     81    return slot->base.name;
     82 }
     83 
     84 NSS_IMPLEMENT void
     85 nssSlot_ResetDelay(
     86    NSSSlot *slot)
     87 {
     88    PZ_Lock(slot->isPresentLock);
     89    slot->lastTokenPingState = nssSlotLastPingState_Reset;
     90    PZ_Unlock(slot->isPresentLock);
     91 }
     92 
     93 static PRBool
     94 token_status_checked(const NSSSlot *slot)
     95 {
     96    PRIntervalTime time;
     97    int lastPingState = slot->lastTokenPingState;
     98    /* When called from the same thread, that means
     99     * nssSlot_IsTokenPresent() is called recursively through
    100     * nssSlot_Refresh(). Return immediately in that case. */
    101    if (slot->isPresentThread == PR_GetCurrentThread()) {
    102        return PR_TRUE;
    103    }
    104    /* Set the delay time for checking the token presence */
    105    if (s_token_delay_time == 0) {
    106        s_token_delay_time = PR_SecondsToInterval(NSSSLOT_TOKEN_DELAY_TIME);
    107    }
    108    time = PR_IntervalNow();
    109    if ((lastPingState == nssSlotLastPingState_Valid) && ((time - slot->lastTokenPingTime) < s_token_delay_time)) {
    110        return PR_TRUE;
    111    }
    112    return PR_FALSE;
    113 }
    114 
    115 NSS_IMPLEMENT PRBool
    116 nssSlot_IsTokenPresent(
    117    NSSSlot *slot)
    118 {
    119    CK_RV ckrv;
    120    PRStatus nssrv;
    121    NSSToken *nssToken = NULL;
    122    /* XXX */
    123    nssSession *session;
    124    CK_SLOT_INFO slotInfo;
    125    void *epv;
    126    PRBool isPresent = PR_FALSE;
    127    PRBool doUpdateCachedCerts = PR_FALSE;
    128 
    129    /* permanent slots are always present unless they're disabled */
    130    if (nssSlot_IsPermanent(slot)) {
    131        return !PK11_IsDisabled(slot->pk11slot);
    132    }
    133 
    134    /* avoid repeated calls to check token status within set interval */
    135    PZ_Lock(slot->isPresentLock);
    136    if (token_status_checked(slot)) {
    137        CK_FLAGS ckFlags = slot->ckFlags;
    138        PZ_Unlock(slot->isPresentLock);
    139        return ((ckFlags & CKF_TOKEN_PRESENT) != 0);
    140    }
    141    PZ_Unlock(slot->isPresentLock);
    142 
    143    /* First obtain the slot epv before we set up the condition
    144     * variable, so we can just return if we couldn't get it. */
    145    epv = slot->epv;
    146    if (!epv) {
    147        return PR_FALSE;
    148    }
    149 
    150    /* set up condition so only one thread is active in this part of the code at a time */
    151    PZ_Lock(slot->isPresentLock);
    152    while (slot->isPresentThread) {
    153        PR_WaitCondVar(slot->isPresentCondition, PR_INTERVAL_NO_TIMEOUT);
    154    }
    155    /* if we were one of multiple threads here, the first thread will have
    156     * given us the answer, no need to make more queries of the token. */
    157    if (token_status_checked(slot)) {
    158        CK_FLAGS ckFlags = slot->ckFlags;
    159        PZ_Unlock(slot->isPresentLock);
    160        return ((ckFlags & CKF_TOKEN_PRESENT) != 0);
    161    }
    162    /* this is the winning thread, block all others until we've determined
    163     * if the token is present and that it needs initialization. */
    164    slot->lastTokenPingState = nssSlotLastPingState_Update;
    165    slot->isPresentThread = PR_GetCurrentThread();
    166 
    167    PZ_Unlock(slot->isPresentLock);
    168 
    169    nssToken = PK11Slot_GetNSSToken(slot->pk11slot);
    170    if (!nssToken) {
    171        isPresent = PR_FALSE;
    172        goto done;
    173    }
    174 
    175    if (PK11_GetSlotInfo(slot->pk11slot, &slotInfo) != SECSuccess) {
    176        nssToken->base.name[0] = 0; /* XXX */
    177        isPresent = PR_FALSE;
    178        goto done;
    179    }
    180    slot->ckFlags = slotInfo.flags;
    181    /* check for the presence of the token */
    182    if ((slot->ckFlags & CKF_TOKEN_PRESENT) == 0) {
    183        session = nssToken_GetDefaultSession(nssToken);
    184        if (session) {
    185            nssSession_EnterMonitor(session);
    186            /* token is not present */
    187            if (session->handle != CK_INVALID_HANDLE) {
    188                /* session is valid, close and invalidate it */
    189                CKAPI(epv)
    190                    ->C_CloseSession(session->handle);
    191                session->handle = CK_INVALID_HANDLE;
    192            }
    193            nssSession_ExitMonitor(session);
    194        }
    195        if (nssToken->base.name[0] != 0) {
    196            /* notify the high-level cache that the token is removed */
    197            nssToken->base.name[0] = 0; /* XXX */
    198            nssToken_NotifyCertsNotVisible(nssToken);
    199        }
    200        nssToken->base.name[0] = 0; /* XXX */
    201        /* clear the token cache */
    202        nssToken_Remove(nssToken);
    203        isPresent = PR_FALSE;
    204        goto done;
    205    }
    206    /* token is present, use the session info to determine if the card
    207     * has been removed and reinserted.
    208     */
    209    session = nssToken_GetDefaultSession(nssToken);
    210    if (session) {
    211        PRBool tokenRemoved;
    212        nssSession_EnterMonitor(session);
    213        if (session->handle != CK_INVALID_HANDLE) {
    214            CK_SESSION_INFO sessionInfo;
    215            ckrv = CKAPI(epv)->C_GetSessionInfo(session->handle, &sessionInfo);
    216            if (ckrv != CKR_OK) {
    217                /* session is screwy, close and invalidate it */
    218                CKAPI(epv)
    219                    ->C_CloseSession(session->handle);
    220                session->handle = CK_INVALID_HANDLE;
    221            }
    222        }
    223        tokenRemoved = (session->handle == CK_INVALID_HANDLE);
    224        nssSession_ExitMonitor(session);
    225        /* token not removed, finished */
    226        if (!tokenRemoved) {
    227            isPresent = PR_TRUE;
    228            goto done;
    229        }
    230    }
    231    /* the token has been removed, and reinserted, or the slot contains
    232     * a token it doesn't recognize. invalidate all the old
    233     * information we had on this token, if we can't refresh, clear
    234     * the present flag */
    235    nssToken_NotifyCertsNotVisible(nssToken);
    236    nssToken_Remove(nssToken);
    237    if (nssToken->base.name[0] == 0) {
    238        doUpdateCachedCerts = PR_TRUE;
    239    }
    240    if (PK11_InitToken(slot->pk11slot, PR_FALSE) != SECSuccess) {
    241        isPresent = PR_FALSE;
    242        goto done;
    243    }
    244    if (doUpdateCachedCerts) {
    245        nssTrustDomain_UpdateCachedTokenCerts(nssToken->trustDomain,
    246                                              nssToken);
    247    }
    248    nssrv = nssToken_Refresh(nssToken);
    249    if (nssrv != PR_SUCCESS) {
    250        nssToken->base.name[0] = 0; /* XXX */
    251        slot->ckFlags &= ~CKF_TOKEN_PRESENT;
    252        isPresent = PR_FALSE;
    253        goto done;
    254    }
    255    isPresent = PR_TRUE;
    256 done:
    257    if (nssToken) {
    258        (void)nssToken_Destroy(nssToken);
    259    }
    260    /* Once we've set up the condition variable,
    261     * Before returning, it's necessary to:
    262     *  1) Set the lastTokenPingTime so that any other threads waiting on this
    263     *     initialization and any future calls within the initialization window
    264     *     return the just-computed status.
    265     *  2) Indicate we're complete, waking up all other threads that may still
    266     *     be waiting on initialization can progress.
    267     */
    268    PZ_Lock(slot->isPresentLock);
    269    /* don't update the time if we were reset while we were
    270     * getting the token state */
    271    if (slot->lastTokenPingState == nssSlotLastPingState_Update) {
    272        slot->lastTokenPingTime = PR_IntervalNow();
    273        slot->lastTokenPingState = nssSlotLastPingState_Valid;
    274    }
    275    slot->isPresentThread = NULL;
    276    PR_NotifyAllCondVar(slot->isPresentCondition);
    277    PZ_Unlock(slot->isPresentLock);
    278    return isPresent;
    279 }
    280 
    281 NSS_IMPLEMENT void *
    282 nssSlot_GetCryptokiEPV(
    283    NSSSlot *slot)
    284 {
    285    return slot->epv;
    286 }
    287 
    288 NSS_IMPLEMENT NSSToken *
    289 nssSlot_GetToken(
    290    NSSSlot *slot)
    291 {
    292    NSSToken *rvToken = NULL;
    293 
    294    if (nssSlot_IsTokenPresent(slot)) {
    295        rvToken = PK11Slot_GetNSSToken(slot->pk11slot);
    296    }
    297 
    298    return rvToken;
    299 }
    300 
    301 NSS_IMPLEMENT PRStatus
    302 nssSession_EnterMonitor(
    303    nssSession *s)
    304 {
    305    if (s->lock)
    306        PZ_Lock(s->lock);
    307    return PR_SUCCESS;
    308 }
    309 
    310 NSS_IMPLEMENT PRStatus
    311 nssSession_ExitMonitor(
    312    nssSession *s)
    313 {
    314    return (s->lock) ? PZ_Unlock(s->lock) : PR_SUCCESS;
    315 }
    316 
    317 NSS_EXTERN PRBool
    318 nssSession_IsReadWrite(
    319    nssSession *s)
    320 {
    321    return s->isRW;
    322 }