[apple/securityd.git] / src / kcdatabase.cpp

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 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
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//
// kcdatabase - software database container implementation.
//
// General implementation notes:
// This leverages LocalDatabase/LocalKey for cryptography, and adds the
//  storage coder/decoder logic that implements "keychain" databases in their
//  intricately choreographed dance between securityd and the AppleCSPDL.
// As always, Database objects are lifetime-bound to their Process referent;
//  they can also be destroyed explicitly with a client release call.
// DbCommons are reference-held by their Databases, with one extra special
//  reference (from the Session) introduced when the database unlocks, and
//  removed when it locks again. That way, an unused DbCommon dies when it
//  is locked or when the Session dies, whichever happens earlier.
// There is (as yet) no global-scope Database object for Keychain databases.
//
#include "kcdatabase.h"
#include "agentquery.h"
#include "kckey.h"
#include "server.h"
#include "session.h"
#include "notifications.h"
#include <vector>           // @@@  4003540 workaround
#include <security_agent_client/agentclient.h>
#include <security_cdsa_utilities/acl_any.h>    // for default owner ACLs
#include <security_cdsa_utilities/cssmendian.h>
#include <security_cdsa_client/wrapkey.h>
#include <security_cdsa_client/genkey.h>
#include <security_cdsa_client/signclient.h>
#include <security_cdsa_client/cryptoclient.h>
#include <security_cdsa_client/macclient.h>
#include <securityd_client/dictionary.h>
#include <security_utilities/endian.h>
#include "securityd_service/securityd_service/securityd_service_client.h"
#include <AssertMacros.h>
#include <syslog.h>

void unflattenKey(const CssmData &flatKey, CssmKey &rawKey);    //>> make static method on KeychainDatabase

static int
unlock_keybag(KeychainDbCommon & dbCommon, const void * secret, int secret_len)
{
    int rc = -1;

    if (!dbCommon.isLoginKeychain()) return 0;
    
    service_context_t context = dbCommon.session().get_current_service_context();
    
    // try to unlock first if not found then load/create or unlock
    // loading should happen when the kb common object is created
    // if it doesn't exist yet then the unlock will fail and we'll create everything
    rc = service_client_kb_unlock(&context, secret, secret_len);
    if (rc == KB_BagNotLoaded) {
        if (service_client_kb_load(&context) == KB_BagNotFound) {
            rc = service_client_kb_create(&context, secret, secret_len);
        } else {
            rc = service_client_kb_unlock(&context, secret, secret_len);
        }
    }

    if (rc == 0) {
        dbCommon.session().keybagSetState(session_keybag_unlocked|session_keybag_loaded);
    }

    return rc;
}

static void
change_secret_on_keybag(KeychainDbCommon & dbCommon, const void * secret, int secret_len, const void * new_secret, int new_secret_len)
{
    if (!dbCommon.isLoginKeychain()) return;

    service_context_t context = dbCommon.session().get_current_service_context();

    // if a login.keychain doesn't exist yet it comes into securityd as a create then change_secret
    // we need to create the keybag in this case if it doesn't exist
    if (service_client_kb_change_secret(&context, secret, secret_len, new_secret, new_secret_len) == KB_BagNotLoaded) {
        if (service_client_kb_load(&context) == KB_BagNotFound) {
            service_client_kb_create(&context, new_secret, new_secret_len);
        }
    }
}

//
// Create a Database object from initial parameters (create operation)
//
KeychainDatabase::KeychainDatabase(const DLDbIdentifier &id, const DBParameters &params, Process &proc,
            const AccessCredentials *cred, const AclEntryPrototype *owner)
    : LocalDatabase(proc), mValidData(false), mSecret(Allocator::standard(Allocator::sensitive)), mSaveSecret(false), version(0), mBlob(NULL)
{
    // save a copy of the credentials for later access control
    mCred = DataWalkers::copy(cred, Allocator::standard());

    // create a new random signature to complete the DLDbIdentifier
    DbBlob::Signature newSig;
    Server::active().random(newSig.bytes);
    DbIdentifier ident(id, newSig);
        
    // create common block and initialize
        RefPointer<KeychainDbCommon> newCommon = new KeychainDbCommon(proc.session(), ident);
        StLock<Mutex> _(*newCommon);
        parent(*newCommon);
        // new common is now visible (in ident-map) but we hold its lock

        // establish the new master secret
        establishNewSecrets(cred, SecurityAgent::newDatabase);
        
        // set initial database parameters
        common().mParams = params;
                
        // the common is "unlocked" now
        common().makeNewSecrets();

        // establish initial ACL
        if (owner)
                acl().cssmSetInitial(*owner);
        else
                acl().cssmSetInitial(new AnyAclSubject());
    mValidData = true;
    
    // for now, create the blob immediately
    encode();
    
        proc.addReference(*this);
        
        // this new keychain is unlocked; make it so
        activity();
        
        SECURITYD_KEYCHAIN_CREATE(&common(), (char*)this->dbName(), this);
}


//
// Create a Database object from a database blob (decoding)
//
KeychainDatabase::KeychainDatabase(const DLDbIdentifier &id, const DbBlob *blob, Process &proc,
    const AccessCredentials *cred)
        : LocalDatabase(proc), mValidData(false), mSecret(Allocator::standard(Allocator::sensitive)), mSaveSecret(false), version(0), mBlob(NULL)
{
        validateBlob(blob);

    // save a copy of the credentials for later access control
    mCred = DataWalkers::copy(cred, Allocator::standard());
    mBlob = blob->copy();
    
    // check to see if we already know about this database
    DbIdentifier ident(id, blob->randomSignature);
        Session &session = process().session();
        StLock<Mutex> _(session);
        if (KeychainDbCommon *dbcom =
                        session.findFirst<KeychainDbCommon, const DbIdentifier &>(&KeychainDbCommon::identifier, ident)) {
                parent(*dbcom);
                //@@@ arbitrate sequence number here, perhaps update common().mParams
                SECURITYD_KEYCHAIN_JOIN(&common(), (char*)this->dbName(), this);
        } else {
                // DbCommon not present; make a new one
                parent(*new KeychainDbCommon(proc.session(), ident));
                common().mParams = blob->params;
                SECURITYD_KEYCHAIN_MAKE(&common(), (char*)this->dbName(), this);
                // this DbCommon is locked; no timer or reference setting
        }
        proc.addReference(*this);
}


// recode/clone:
//
// Special-purpose constructor for keychain synchronization.  Copies an
// existing keychain but uses the operational keys from secretsBlob.  The 
// new KeychainDatabase will silently replace the existing KeychainDatabase
// as soon as the client declares that re-encoding of all keychain items is
// finished.  This is a little perilous since it allows a client to dictate
// securityd state, but we try to ensure that only the client that started 
// the re-encoding can declare it done.  
//
KeychainDatabase::KeychainDatabase(KeychainDatabase &src, Process &proc, DbHandle dbToClone)
        : LocalDatabase(proc), mValidData(false), mSecret(Allocator::standard(Allocator::sensitive)), mSaveSecret(false), version(0), mBlob(NULL)
{
        mCred = DataWalkers::copy(src.mCred, Allocator::standard());

        // Give this KeychainDatabase a temporary name
        std::string newDbName = std::string("////") + std::string(src.identifier().dbName());
        DLDbIdentifier newDLDbIdent(src.identifier().dlDbIdentifier().ssuid(), newDbName.c_str(), src.identifier().dlDbIdentifier().dbLocation());
        DbIdentifier ident(newDLDbIdent, src.identifier());

    // create common block and initialize
        RefPointer<KeychainDbCommon> newCommon = new KeychainDbCommon(proc.session(), ident);
        StLock<Mutex> _(*newCommon);
        parent(*newCommon);

        // set initial database parameters from the source keychain
        common().mParams = src.common().mParams;
        
        // establish the source keychain's master secret as ours
        // @@@  NB: this is a v. 0.1 assumption.  We *should* trigger new UI 
        //      that offers the user the option of using the existing password 
        //      or choosing a new one.  That would require a new 
        //      SecurityAgentQuery type, new UI, and--possibly--modifications to
        //      ensure that the new password is available here to generate the 
        //      new master secret.  
        src.unlockDb();         // precaution for masterKey()
        common().setup(src.blob(), src.common().masterKey());
        
    // import the operational secrets
        RefPointer<KeychainDatabase> srcKC = Server::keychain(dbToClone);
        common().importSecrets(srcKC->common());
        
        // import source keychain's ACL  
        CssmData pubAcl, privAcl;
        src.acl().exportBlob(pubAcl, privAcl);
        importBlob(pubAcl.data(), privAcl.data());
        src.acl().allocator.free(pubAcl);
        src.acl().allocator.free(privAcl);
        
        // indicate that this keychain should be allowed to do some otherwise
        // risky things required for copying, like re-encoding keys
        mRecodingSource = &src;
        
        common().setUnlocked();
        mValidData = true;
        
    encode();

        proc.addReference(*this);
        secdebug("SSdb", "database %s(%p) created as copy, common at %p",
                         common().dbName(), this, &common());
}

//
// Destroy a Database
//
KeychainDatabase::~KeychainDatabase()
{
    secdebug("KCdb", "deleting database %s(%p) common %p",
        common().dbName(), this, &common());
    Allocator::standard().free(mCred);
        Allocator::standard().free(mBlob);
}


//
// Basic Database virtual implementations
//
KeychainDbCommon &KeychainDatabase::common() const
{
        return parent<KeychainDbCommon>();
}

const char *KeychainDatabase::dbName() const
{
        return common().dbName();
}

bool KeychainDatabase::transient() const
{
        return false;   // has permanent store
}

AclKind KeychainDatabase::aclKind() const
{
        return dbAcl;
}

Database *KeychainDatabase::relatedDatabase()
{
        return this;
}


static inline KeychainKey &myKey(Key *key)
{
        return *safe_cast<KeychainKey *>(key);
}


//
// (Re-)Authenticate the database. This changes the stored credentials.
//
void KeychainDatabase::authenticate(CSSM_DB_ACCESS_TYPE mode,
        const AccessCredentials *cred)
{
        StLock<Mutex> _(common());
        
        // the (Apple specific) RESET bit means "lock the database now"
        switch (mode) {
        case CSSM_DB_ACCESS_RESET:
                secdebug("KCdb", "%p ACCESS_RESET triggers keychain lock", this);
                common().lockDb();
                break;
        default:
                //  store the new credentials for future use
                secdebug("KCdb", "%p authenticate stores new database credentials", this);
                AccessCredentials *newCred = DataWalkers::copy(cred, Allocator::standard());
                Allocator::standard().free(mCred);
                mCred = newCred;
        }
}


//
// Make a new KeychainKey.
// If PERMANENT is off, make a temporary key instead.
// The db argument allows you to create for another KeychainDatabase (only);
// it defaults to ourselves.
//
RefPointer<Key> KeychainDatabase::makeKey(Database &db, const CssmKey &newKey,
        uint32 moreAttributes, const AclEntryPrototype *owner)
{

        if (moreAttributes & CSSM_KEYATTR_PERMANENT)
                return new KeychainKey(db, newKey, moreAttributes, owner);
        else
                return process().makeTemporaryKey(newKey, moreAttributes, owner);
}

RefPointer<Key> KeychainDatabase::makeKey(const CssmKey &newKey,
        uint32 moreAttributes, const AclEntryPrototype *owner)
{
        return makeKey(*this, newKey, moreAttributes, owner);
}


//
// Return the database blob, recalculating it as needed.
//
DbBlob *KeychainDatabase::blob()
{
        StLock<Mutex> _(common());
    if (!validBlob()) {
        makeUnlocked();                 // unlock to get master secret
                encode();                               // (re)encode blob if needed
    }
    activity();                                 // reset timeout
        assert(validBlob());            // better have a valid blob now...
    return mBlob;
}


//
// Encode the current database as a blob.
// Note that this returns memory we own and keep.
// Caller must hold common lock.
//
void KeychainDatabase::encode()
{
        DbBlob *blob = common().encode(*this);
        Allocator::standard().free(mBlob);
        mBlob = blob;
        version = common().version;
        secdebug("KCdb", "encoded database %p common %p(%s) version %u params=(%u,%u)",
                this, &common(), dbName(), version,
                common().mParams.idleTimeout, common().mParams.lockOnSleep);
}


//
// Change the passphrase on a database
//
void KeychainDatabase::changePassphrase(const AccessCredentials *cred)
{
        // get and hold the common lock (don't let other threads break in here)
        StLock<Mutex> _(common());
        
        // establish OLD secret - i.e. unlock the database
        //@@@ do we want to leave the final lock state alone?
    if (common().isLoginKeychain()) mSaveSecret = true;
        makeUnlocked(cred);
        
    // establish NEW secret
        establishNewSecrets(cred, SecurityAgent::changePassphrase);
    if (mSecret) { mSecret.reset(); }
    mSaveSecret = false;
        common().invalidateBlob();      // blob state changed
        secdebug("KCdb", "Database %s(%p) master secret changed", common().dbName(), this);
        encode();                       // force rebuild of local blob
        
        // send out a notification
        notify(kNotificationEventPassphraseChanged);

    // I guess this counts as an activity
    activity();
}

//
// Second stage of keychain synchronization: overwrite the original keychain's
// (this KeychainDatabase's) operational secrets
//
void KeychainDatabase::commitSecretsForSync(KeychainDatabase &cloneDb)
{
    StLock<Mutex> _(common());
    
        // try to detect spoofing
        if (cloneDb.mRecodingSource != this) 
        CssmError::throwMe(CSSM_ERRCODE_INVALID_DB_HANDLE);
        
    // in case we autolocked since starting the sync
    makeUnlocked(); // call this because we already own the lock
        cloneDb.unlockDb(); // we may not own the lock here, so calling unlockDb will lock the cloneDb's common lock

    // Decode all keys whose handles refer to this on-disk keychain so that
    // if the holding client commits the key back to disk, it's encoded with
    // the new operational secrets.  The recoding client *must* hold a write
    // lock for the on-disk keychain from the moment it starts recoding key
    // items until after this call.  
    // 
        // @@@  This specific implementation is a workaround for 4003540.  
        std::vector<U32HandleObject::Handle> handleList;
        U32HandleObject::findAllRefs<KeychainKey>(handleList);
    size_t count = handleList.size();
        if (count > 0) {
        for (unsigned int n = 0; n < count; ++n) {
            RefPointer<KeychainKey> kckey = 
                U32HandleObject::findRefAndLock<KeychainKey>(handleList[n], CSSMERR_CSP_INVALID_KEY_REFERENCE);
            StLock<Mutex> _(*kckey/*, true*/);
            if (kckey->database().global().identifier() == identifier()) {
                kckey->key();               // force decode
                kckey->invalidateBlob();
                                secdebug("kcrecode", "changed extant key %p (proc %d)",
                                                 &*kckey, kckey->process().pid());
            }
        }
        }

    // it is now safe to replace the old op secrets
    common().importSecrets(cloneDb.common());
        common().invalidateBlob();
}


//
// Extract the database master key as a proper Key object.
//
RefPointer<Key> KeychainDatabase::extractMasterKey(Database &db,
        const AccessCredentials *cred, const AclEntryPrototype *owner,
        uint32 usage, uint32 attrs)
{
        // get and hold common lock
        StLock<Mutex> _(common());
        
        // force lock to require re-validation of credentials
        lockDb();
        
        // unlock to establish master secret
        makeUnlocked();
        
        // extract the raw cryptographic key
        CssmClient::WrapKey wrap(Server::csp(), CSSM_ALGID_NONE);
        CssmKey key;
        wrap(common().masterKey(), key);
        
        // make the key object and return it
        return makeKey(db, key, attrs & LocalKey::managedAttributes, owner);
}


//
// Unlock this database (if needed) by obtaining the master secret in some
// suitable way and then proceeding to unlock with it.
// Does absolutely nothing if the database is already unlocked.
// The makeUnlocked forms are identical except the assume the caller already
// holds the common lock.
//
void KeychainDatabase::unlockDb()
{
        StLock<Mutex> _(common());
        makeUnlocked();
}

void KeychainDatabase::makeUnlocked()
{
        return makeUnlocked(mCred);
}

void KeychainDatabase::makeUnlocked(const AccessCredentials *cred)
{
    if (isLocked()) {
                secdebug("KCdb", "%p(%p) unlocking for makeUnlocked()", this, &common());
        assert(mBlob || (mValidData && common().hasMaster()));
                establishOldSecrets(cred);
                common().setUnlocked(); // mark unlocked
        } else if (common().isLoginKeychain()) {
        bool locked = false;
        service_context_t context = common().session().get_current_service_context();
        if ((service_client_kb_is_locked(&context, &locked, NULL) == 0) && locked) {
            StSyncLock<Mutex, Mutex> uisync(common().uiLock(), common());
            QueryKeybagPassphrase keybagQuery(common().session(), 3);
            keybagQuery.inferHints(Server::process());
            if (keybagQuery.query() != SecurityAgent::noReason) {
                syslog(LOG_NOTICE, "failed to unlock iCloud keychain");
            }
        }
    }
        if (!mValidData) {      // need to decode to get our ACLs, master secret available
                secdebug("KCdb", "%p(%p) is unlocked; decoding for makeUnlocked()", this, &common());
                if (!decode())
                        CssmError::throwMe(CSSM_ERRCODE_OPERATION_AUTH_DENIED);
        }
        assert(!isLocked());
        assert(mValidData);
}

//
// Invoke the securityd_service to retrieve the keychain master
// key from the AppleFDEKeyStore.
//
void KeychainDatabase::stashDbCheck()
{    
    CssmAutoData data(Allocator::standard(Allocator::sensitive));

    // Fetch the key
    int rc = 0;
    void * stash_key = NULL;
    int stash_key_len = 0;
    service_context_t context = common().session().get_current_service_context();
    rc = service_client_stash_get_key(&context, &stash_key, &stash_key_len);
    if (rc == 0) {
        if (stash_key) {
            data.copy(CssmData((void *)stash_key,stash_key_len));
            memset(stash_key, 0, stash_key_len);
            free(stash_key);
        }
    } else {
        CssmError::throwMe(rc);
    }
    
    {
        StLock<Mutex> _(common());

        // Now establish it as the keychain master key
        CssmClient::Key key(Server::csp(), data.get());
        CssmKey::Header &hdr = key.header();
        hdr.keyClass(CSSM_KEYCLASS_SESSION_KEY);
        hdr.algorithm(CSSM_ALGID_3DES_3KEY_EDE);
        hdr.usage(CSSM_KEYUSE_ANY);
        hdr.blobType(CSSM_KEYBLOB_RAW);
        hdr.blobFormat(CSSM_KEYBLOB_RAW_FORMAT_OCTET_STRING);
        common().setup(mBlob, key);

        if (!decode())
            CssmError::throwMe(CSSM_ERRCODE_OPERATION_AUTH_DENIED);
    }

    // when upgrading from pre-10.9 create a keybag if it doesn't exist with the master secret
    // only do this after we have verified the master key unlocks the login.keychain
    if (service_client_kb_load(&context) == KB_BagNotFound) {
        service_client_kb_create(&context, data.data(), (int)data.length());
    }
}

//
// Get the keychain master key and invoke the securityd_service
// to stash it in the AppleFDEKeyStore ready for commit to the
// NVRAM blob.
//
void KeychainDatabase::stashDb()
{
    CssmAutoData data(Allocator::standard(Allocator::sensitive));
    
    {
        StLock<Mutex> _(common());

        if (!common().isValid()) {
            CssmError::throwMe(CSSMERR_CSP_INVALID_KEY);
        }
        
        CssmKey key = common().masterKey();
        data.copy(key.keyData());
    }
    
    service_context_t context = common().session().get_current_service_context();
    int rc = service_client_stash_set_key(&context, data.data(), (int)data.length());
    if (rc != 0) CssmError::throwMe(rc);
}

//
// The following unlock given an explicit passphrase, rather than using
// (special cred sample based) default procedures.
//
void KeychainDatabase::unlockDb(const CssmData &passphrase)
{
        StLock<Mutex> _(common());
        makeUnlocked(passphrase);
}

void KeychainDatabase::makeUnlocked(const CssmData &passphrase)
{
        if (isLocked()) {
                if (decode(passphrase))
                        return;
                else
                        CssmError::throwMe(CSSM_ERRCODE_OPERATION_AUTH_DENIED);
        } else if (!mValidData) {       // need to decode to get our ACLs, passphrase available
                if (!decode())
                        CssmError::throwMe(CSSM_ERRCODE_OPERATION_AUTH_DENIED);
        }

    if (common().isLoginKeychain()) {
        bool locked = false;
        service_context_t context = common().session().get_current_service_context();
        if ((service_client_kb_is_locked(&context, &locked, NULL) == 0) && locked) {
            unlock_keybag(common(), passphrase.data(), (int)passphrase.length());
        }
    }

        assert(!isLocked());
        assert(mValidData);
}


//
// Nonthrowing passphrase-based unlock. This returns false if unlock failed.
// Note that this requires an explicitly given passphrase.
// Caller must hold common lock.
//
bool KeychainDatabase::decode(const CssmData &passphrase)
{
        assert(mBlob);
        common().setup(mBlob, passphrase);
        bool success = decode();
    if (success) {
        if (common().isLoginKeychain() && (unlock_keybag(common(), passphrase.data(), (int)passphrase.length()) != 0)) {
            service_context_t context = common().session().get_current_service_context();
            // check to see if it was locked with the master key if so change the secret to the passphrase
            if (!common().session().keybagGetState(session_keybag_check_master_key)) {

                CssmAutoData key(Allocator::standard(Allocator::sensitive));
                key = common().masterKey()->keyData();
                if (service_client_kb_unlock(&context, key.data(), (int)key.length()) == 0) {
                    service_client_kb_change_secret(&context, key.data(), (int)key.length(), passphrase.data(), (int)passphrase.length());
                }
                common().session().keybagSetState(session_keybag_check_master_key);
            }

            bool no_pin = false;
            if (service_client_kb_is_locked(&context, NULL, &no_pin) == 0) {
                if ((passphrase.length() > 0) && no_pin) {
                    syslog(LOG_ERR, "Updating passphrase for your iCloud keychain");
                    service_client_kb_change_secret(&context, NULL, 0, passphrase.data(), (int)passphrase.length());
                } else {
                    syslog(LOG_ERR, "The passphrase for your login.keychain and your iCloud keychain are out of sync");
                }
            }
        }
    }
    return success;
}


//
// Given the established master secret, decode the working keys and other
// functional secrets for this database. Return false (do NOT throw) if
// the decode fails. Call this in low(er) level code once you established
// the master key.
//
bool KeychainDatabase::decode()
{
        assert(mBlob);
        assert(common().hasMaster());
        void *privateAclBlob;
        if (common().unlockDb(mBlob, &privateAclBlob)) {
                if (!mValidData) {
                        acl().importBlob(mBlob->publicAclBlob(), privateAclBlob);
                        mValidData = true;
                }
                Allocator::standard().free(privateAclBlob);
                return true;
        }
        secdebug("KCdb", "%p decode failed", this);
        return false;
}


//
// Given an AccessCredentials for this database, wring out the existing primary
// database secret by whatever means necessary.
// On entry, caller must hold the database common lock. It will be held
// throughout except when user interaction is required. User interaction 
// requires relinquishing the database common lock and taking the UI lock. On
// return from user interaction, the UI lock is relinquished and the database
// common lock must be reacquired. At no time may the caller hold both locks.
// On exit, the crypto core has its master secret. If things go wrong,
// we will throw a suitable exception. Note that encountering any malformed
// credential sample will throw, but this is not guaranteed -- don't assume
// that NOT throwing means creds is entirely well-formed (it may just be good
// enough to work THIS time).
//
// How this works:
// Walk through the creds. Fish out those credentials (in order) that
// are for unlock processing (they have no ACL subject correspondents),
// and (try to) obey each in turn, until one produces a valid secret
// or you run out. If no special samples are found at all, interpret that as
// "use the system global default," which happens to be hard-coded right here.
//
void KeychainDatabase::establishOldSecrets(const AccessCredentials *creds)
{
        bool forSystem = this->belongsToSystem();       // this keychain belongs to the system security domain

        // attempt system-keychain unlock
        if (forSystem) {
                SystemKeychainKey systemKeychain(kSystemUnlockFile);
                if (systemKeychain.matches(mBlob->randomSignature)) {
                        secdebug("KCdb", "%p attempting system unlock", this);
                        common().setup(mBlob, CssmClient::Key(Server::csp(), systemKeychain.key(), true));
                        if (decode())
                                return;
                }
        }
    
        list<CssmSample> samples;
        if (creds && creds->samples().collect(CSSM_SAMPLE_TYPE_KEYCHAIN_LOCK, samples)) {
                for (list<CssmSample>::iterator it = samples.begin(); it != samples.end(); it++) {
                        TypedList &sample = *it;
                        sample.checkProper();
                        switch (sample.type()) {
                        // interactively prompt the user - no additional data
                        case CSSM_SAMPLE_TYPE_KEYCHAIN_PROMPT:
                                if (!forSystem) {
                                        if (interactiveUnlock())
                                                return;
                                }
                break;
                        // try to use an explicitly given passphrase - Data:passphrase
                        case CSSM_SAMPLE_TYPE_PASSWORD:
                                if (sample.length() != 2)
                                        CssmError::throwMe(CSSM_ERRCODE_INVALID_SAMPLE_VALUE);
                                secdebug("KCdb", "%p attempting passphrase unlock", this);
                                if (decode(sample[1]))
                                        return;
                                break;
                        // try to open with a given master key - Data:CSP or KeyHandle, Data:CssmKey
                        case CSSM_SAMPLE_TYPE_SYMMETRIC_KEY:
                        case CSSM_SAMPLE_TYPE_ASYMMETRIC_KEY:
                                assert(mBlob);
                                secdebug("KCdb", "%p attempting explicit key unlock", this);
                                common().setup(mBlob, keyFromCreds(sample, 4));
                                if (decode())
                                        return;
                                break;
                        // explicitly defeat the default action but don't try anything in particular
                        case CSSM_WORDID_CANCELED:
                                secdebug("KCdb", "%p defeat default action", this);
                                break;
                        default:
                                // Unknown sub-sample for unlocking.
                                // If we wanted to be fascist, we could now do
                                //  CssmError::throwMe(CSSM_ERRCODE_SAMPLE_VALUE_NOT_SUPPORTED);
                                // But instead we try to be tolerant and continue on.
                                // This DOES however count as an explicit attempt at specifying unlock,
                                // so we will no longer try the default case below...
                                secdebug("KCdb", "%p unknown sub-sample unlock (%d) ignored", this, sample.type());
                                break;
                        }
                }
        } else {
                // default action
                assert(mBlob);

                if (!forSystem) {
                        if (interactiveUnlock())
                                return;
                }
        }
        
        // out of options - no secret obtained
        CssmError::throwMe(CSSM_ERRCODE_OPERATION_AUTH_DENIED);
}

bool KeychainDatabase::interactiveUnlock()
{
        secdebug("KCdb", "%p attempting interactive unlock", this);
        SecurityAgent::Reason reason = SecurityAgent::noReason;
    QueryUnlock query(*this);
        // take UI interlock and release DbCommon lock (to avoid deadlocks)
        StSyncLock<Mutex, Mutex> uisync(common().uiLock(), common());
        
        // now that we have the UI lock, interact unless another thread unlocked us first
        if (isLocked()) {
                query.inferHints(Server::process());
        reason = query();
        if (mSaveSecret && reason == SecurityAgent::noReason) {
            query.retrievePassword(mSecret);
        }
        query.disconnect();
        } else {
                secdebug("KCdb", "%p was unlocked during uiLock delay", this);
        }

    if (common().isLoginKeychain()) {
        bool locked = false;
        service_context_t context = common().session().get_current_service_context();
        if ((service_client_kb_is_locked(&context, &locked, NULL) == 0) && locked) {
            QueryKeybagNewPassphrase keybagQuery(common().session());
            keybagQuery.inferHints(Server::process());
            CssmAutoData pass(Allocator::standard(Allocator::sensitive));
            CssmAutoData oldPass(Allocator::standard(Allocator::sensitive));
            SecurityAgent::Reason queryReason = keybagQuery.query(oldPass, pass);
            if (queryReason == SecurityAgent::noReason) {
                service_client_kb_change_secret(&context, oldPass.data(), (int)oldPass.length(), pass.data(), (int)pass.length());
            } else if (queryReason == SecurityAgent::resettingPassword) {
                query.retrievePassword(pass);
                service_client_kb_reset(&context, pass.data(), (int)pass.length());
            }

        }
    }

    return reason == SecurityAgent::noReason;
}


//
// Same thing, but obtain a new secret somehow and set it into the common.
//
void KeychainDatabase::establishNewSecrets(const AccessCredentials *creds, SecurityAgent::Reason reason)
{
        list<CssmSample> samples;
        if (creds && creds->samples().collect(CSSM_SAMPLE_TYPE_KEYCHAIN_CHANGE_LOCK, samples)) {
                for (list<CssmSample>::iterator it = samples.begin(); it != samples.end(); it++) {
                        TypedList &sample = *it;
                        sample.checkProper();
                        switch (sample.type()) {
                        // interactively prompt the user
                        case CSSM_SAMPLE_TYPE_KEYCHAIN_PROMPT:
                {
                                secdebug("KCdb", "%p specified interactive passphrase", this);
                                QueryNewPassphrase query(*this, reason);
                                StSyncLock<Mutex, Mutex> uisync(common().uiLock(), common());
                                query.inferHints(Server::process());
                                CssmAutoData passphrase(Allocator::standard(Allocator::sensitive));
                CssmAutoData oldPassphrase(Allocator::standard(Allocator::sensitive));
                                if (query(oldPassphrase, passphrase) == SecurityAgent::noReason) {
                                        common().setup(NULL, passphrase);
                    change_secret_on_keybag(common(), oldPassphrase.data(), (int)oldPassphrase.length(), passphrase.data(), (int)passphrase.length());
                                        return;
                                }
                }
                                break;
                        // try to use an explicitly given passphrase
                        case CSSM_SAMPLE_TYPE_PASSWORD:
                                {
                    secdebug("KCdb", "%p specified explicit passphrase", this);
                    if (sample.length() != 2)
                        CssmError::throwMe(CSSM_ERRCODE_INVALID_SAMPLE_VALUE);
                    common().setup(NULL, sample[1]);
                    if (common().isLoginKeychain()) {
                        CssmAutoData oldPassphrase(Allocator::standard(Allocator::sensitive));
                        list<CssmSample> oldSamples;
                        creds->samples().collect(CSSM_SAMPLE_TYPE_KEYCHAIN_LOCK, oldSamples);
                        for (list<CssmSample>::iterator oit = oldSamples.begin(); oit != oldSamples.end(); oit++) {
                            TypedList &tmpList = *oit;
                            tmpList.checkProper();
                            if (tmpList.type() == CSSM_SAMPLE_TYPE_PASSWORD) {
                                if (tmpList.length() == 2) {
                                    oldPassphrase = tmpList[1].data();
                                }
                            }
                        }
                        if (!oldPassphrase.length() && mSecret && mSecret.length()) {
                            oldPassphrase = mSecret;
                        }
                        change_secret_on_keybag(common(), oldPassphrase.data(), (int)oldPassphrase.length(), sample[1].data().data(), (int)sample[1].data().length());
                    }
                    return;
                }
                        // try to open with a given master key
                        case CSSM_WORDID_SYMMETRIC_KEY:
                        case CSSM_SAMPLE_TYPE_ASYMMETRIC_KEY:
                                secdebug("KCdb", "%p specified explicit master key", this);
                                common().setup(NULL, keyFromCreds(sample, 3));
                                return;
                        // explicitly defeat the default action but don't try anything in particular
                        case CSSM_WORDID_CANCELED:
                                secdebug("KCdb", "%p defeat default action", this);
                                break;
                        default:
                                // Unknown sub-sample for acquiring new secret.
                                // If we wanted to be fascist, we could now do
                                //  CssmError::throwMe(CSSM_ERRCODE_SAMPLE_VALUE_NOT_SUPPORTED);
                                // But instead we try to be tolerant and continue on.
                                // This DOES however count as an explicit attempt at specifying unlock,
                                // so we will no longer try the default case below...
                                secdebug("KCdb", "%p unknown sub-sample acquisition (%d) ignored",
                                        this, sample.type());
                                break;
                        }
                }
        } else {
                // default action -- interactive (only)
                QueryNewPassphrase query(*this, reason);
                StSyncLock<Mutex, Mutex> uisync(common().uiLock(), common());
        query.inferHints(Server::process());
                CssmAutoData passphrase(Allocator::standard(Allocator::sensitive));
        CssmAutoData oldPassphrase(Allocator::standard(Allocator::sensitive));
                if (query(oldPassphrase, passphrase) == SecurityAgent::noReason) {
                        common().setup(NULL, passphrase);
            change_secret_on_keybag(common(), oldPassphrase.data(), (int)oldPassphrase.length(), passphrase.data(), (int)passphrase.length());
                        return;
                }
        }
        
        // out of options - no secret obtained
        CssmError::throwMe(CSSM_ERRCODE_OPERATION_AUTH_DENIED);
}


//
// Given a (truncated) Database credentials TypedList specifying a master key,
// locate the key and return a reference to it.
//
CssmClient::Key KeychainDatabase::keyFromCreds(const TypedList &sample, unsigned int requiredLength)
{
        // decode TypedList structure (sample type; Data:CSPHandle; Data:CSSM_KEY)
        assert(sample.type() == CSSM_SAMPLE_TYPE_SYMMETRIC_KEY || sample.type() == CSSM_SAMPLE_TYPE_ASYMMETRIC_KEY);
        if (sample.length() != requiredLength
                || sample[1].type() != CSSM_LIST_ELEMENT_DATUM
                || sample[2].type() != CSSM_LIST_ELEMENT_DATUM
                || (requiredLength == 4 && sample[3].type() != CSSM_LIST_ELEMENT_DATUM))
                        CssmError::throwMe(CSSM_ERRCODE_INVALID_SAMPLE_VALUE);
        KeyHandle &handle = *sample[1].data().interpretedAs<KeyHandle>(CSSM_ERRCODE_INVALID_SAMPLE_VALUE);
    // We used to be able to check the length but supporting multiple client
    // architectures dishes that (sizeof(CSSM_KEY) varies due to alignment and
    // field-size differences).  The decoding in the transition layer should 
    // serve as a sufficient garbling check anyway.  
    if (sample[2].data().data() == NULL)
        CssmError::throwMe(CSSM_ERRCODE_INVALID_SAMPLE_VALUE);
    CssmKey &key = *sample[2].data().interpretedAs<CssmKey>();

        if (key.header().cspGuid() == gGuidAppleCSPDL) {
                // handleOrKey is a SecurityServer KeyHandle; ignore key argument
                return safer_cast<LocalKey &>(*Server::key(handle));
        } else 
        if (sample.type() == CSSM_SAMPLE_TYPE_ASYMMETRIC_KEY) {
                /*
                        Contents (see DefaultCredentials::unlockKey in libsecurity_keychain/defaultcreds.cpp)
                        
                        sample[0]       sample type
                        sample[1]       csp handle for master or wrapping key; is really a keyhandle
                        sample[2]       masterKey [not used since securityd cannot interpret; use sample[1] handle instead]
                        sample[3]       UnlockReferralRecord data, in this case the flattened symmetric key
                */

                // RefPointer<Key> Server::key(KeyHandle key)
                KeyHandle keyhandle = *sample[1].data().interpretedAs<KeyHandle>(CSSM_ERRCODE_INVALID_SAMPLE_VALUE);
                CssmData &flattenedKey = sample[3].data();
                RefPointer<Key> unwrappingKey = Server::key(keyhandle);
                Database &db=unwrappingKey->database();
                
                CssmKey rawWrappedKey;
                unflattenKey(flattenedKey, rawWrappedKey);

                RefPointer<Key> masterKey;
                CssmData emptyDescriptiveData;
                const AccessCredentials *cred = NULL;
                const AclEntryPrototype *owner = NULL;
                CSSM_KEYUSE usage = CSSM_KEYUSE_ANY;
                CSSM_KEYATTR_FLAGS attrs = CSSM_KEYATTR_EXTRACTABLE;    //CSSM_KEYATTR_RETURN_REF | 

                // Get default credentials for unwrappingKey (the one on the token)
                // Copied from Statics::Statics() in libsecurity_keychain/aclclient.cpp
                // Following KeyItem::getCredentials, one sees that the "operation" parameter
                // e.g. "CSSM_ACL_AUTHORIZATION_DECRYPT" is ignored
                Allocator &alloc = Allocator::standard();
                AutoCredentials promptCred(alloc, 3);// enable interactive prompting
        
                // promptCred: a credential permitting user prompt confirmations
                // contains:
                //  a KEYCHAIN_PROMPT sample, both by itself and in a THRESHOLD
                //  a PROMPTED_PASSWORD sample
                promptCred.sample(0) = TypedList(alloc, CSSM_SAMPLE_TYPE_KEYCHAIN_PROMPT);
                promptCred.sample(1) = TypedList(alloc, CSSM_SAMPLE_TYPE_THRESHOLD,
                        new(alloc) ListElement(TypedList(alloc, CSSM_SAMPLE_TYPE_KEYCHAIN_PROMPT)));
                promptCred.sample(2) = TypedList(alloc, CSSM_SAMPLE_TYPE_PROMPTED_PASSWORD,
                        new(alloc) ListElement(alloc, CssmData()));

                // This unwrap object is here just to provide a context
                CssmClient::UnwrapKey unwrap(Server::csp(), CSSM_ALGID_NONE);   //ok to lie about csp here
                unwrap.mode(CSSM_ALGMODE_NONE);
                unwrap.padding(CSSM_PADDING_PKCS1);
                unwrap.cred(promptCred);
                unwrap.add(CSSM_ATTRIBUTE_WRAPPED_KEY_FORMAT, uint32(CSSM_KEYBLOB_WRAPPED_FORMAT_PKCS7));
                Security::Context *tmpContext;
                CSSM_CC_HANDLE CCHandle = unwrap.handle();
                /*CSSM_RETURN rx = */ CSSM_GetContext (CCHandle, (CSSM_CONTEXT_PTR *)&tmpContext);
                
                // OK, this is skanky but necessary. We overwrite fields in the context struct

                tmpContext->ContextType = CSSM_ALGCLASS_ASYMMETRIC;
                tmpContext->AlgorithmType = CSSM_ALGID_RSA;
                
                db.unwrapKey(*tmpContext, cred, owner, unwrappingKey, NULL, usage, attrs,
                        rawWrappedKey, masterKey, emptyDescriptiveData);

            Allocator::standard().free(rawWrappedKey.KeyData.Data);

                return safer_cast<LocalKey &>(*masterKey).key();
        }
        else
        {
                // not a KeyHandle reference; use key as a raw key
                if (key.header().blobType() != CSSM_KEYBLOB_RAW)
                        CssmError::throwMe(CSSMERR_CSP_INVALID_KEY_REFERENCE);
                if (key.header().keyClass() != CSSM_KEYCLASS_SESSION_KEY)
                        CssmError::throwMe(CSSMERR_CSP_INVALID_KEY_CLASS);
                return CssmClient::Key(Server::csp(), key, true);
        }
}

void unflattenKey(const CssmData &flatKey, CssmKey &rawKey)
{
        // unflatten the raw input key naively: key header then key data
        // We also convert it back to host byte order
        // A CSSM_KEY is a CSSM_KEYHEADER followed by a CSSM_DATA

        // Now copy: header, then key struct, then key data
        memcpy(&rawKey.KeyHeader, flatKey.Data, sizeof(CSSM_KEYHEADER));
        memcpy(&rawKey.KeyData, flatKey.Data + sizeof(CSSM_KEYHEADER), sizeof(CSSM_DATA));
        const uint32 keyDataLength = flatKey.length() - sizeof(CSSM_KEY);
        rawKey.KeyData.Data = Allocator::standard().malloc<uint8>(keyDataLength);
        rawKey.KeyData.Length = keyDataLength;
        memcpy(rawKey.KeyData.Data, flatKey.Data + sizeof(CSSM_KEY), keyDataLength);
        Security::n2hi(rawKey.KeyHeader);       // convert it to host byte order
}


//
// Verify a putative database passphrase.
// If the database is already unlocked, just check the passphrase.
// Otherwise, unlock with that passphrase and report success.
// Caller must hold the common lock.
//
bool KeychainDatabase::validatePassphrase(const CssmData &passphrase) const
{
        if (common().hasMaster()) {
                // verify against known secret
                return common().validatePassphrase(passphrase);
        } else {
                // no master secret - perform "blind" unlock to avoid actual unlock
                try {
                        DatabaseCryptoCore test;
                        test.setup(mBlob, passphrase);
                        test.decodeCore(mBlob, NULL);
                        return true;
                } catch (...) {
                        return false;
                }
        }
}


//
// Lock this database
//
void KeychainDatabase::lockDb()
{
    common().lockDb();
}


//
// Given a Key for this database, encode it into a blob and return it.
//
KeyBlob *KeychainDatabase::encodeKey(const CssmKey &key, const CssmData &pubAcl, const CssmData &privAcl)
{
        bool inTheClear = false;
        if((key.keyClass() == CSSM_KEYCLASS_PUBLIC_KEY) &&
           !(key.attribute(CSSM_KEYATTR_PUBLIC_KEY_ENCRYPT))) {
                inTheClear = true;
        }
        StLock<Mutex> _(common());
        if(!inTheClear)
                makeUnlocked();
        
    // tell the cryptocore to form the key blob
    return common().encodeKeyCore(key, pubAcl, privAcl, inTheClear);
}


//
// Given a "blobbed" key for this database, decode it into its real
// key object and (re)populate its ACL.
//
void KeychainDatabase::decodeKey(KeyBlob *blob, CssmKey &key, void * &pubAcl, void * &privAcl)
{
        StLock<Mutex> _(common());

        if(!blob->isClearText())
                makeUnlocked();                                                 // we need our keys

        common().decodeKeyCore(blob, key, pubAcl, privAcl);
        // memory protocol: pubAcl points into blob; privAcl was allocated
        
    activity();
}

//
// Given a KeychainKey (that implicitly belongs to another keychain), 
// return it encoded using this keychain's operational secrets.  
//
KeyBlob *KeychainDatabase::recodeKey(KeychainKey &oldKey)
{
        if (mRecodingSource != &oldKey.referent<KeychainDatabase>()) {
        CssmError::throwMe(CSSMERR_CSP_INVALID_KEY);
    }
        oldKey.instantiateAcl();        // make sure key is decoded
        CssmData publicAcl, privateAcl;
        oldKey.exportBlob(publicAcl, privateAcl);
        // NB: blob's memory belongs to caller, not the common

        /* 
         * Make sure the new key is in the same cleartext/encrypted state.
         */
        bool inTheClear = false;
        assert(oldKey.blob());
        if(oldKey.blob() && oldKey.blob()->isClearText()) {
                /* careful....*/
                inTheClear = true;
        }
        KeyBlob *blob = common().encodeKeyCore(oldKey.cssmKey(), publicAcl, privateAcl, inTheClear);
        oldKey.acl().allocator.free(publicAcl);
        oldKey.acl().allocator.free(privateAcl);
        return blob;
}


//
// Modify database parameters
//
void KeychainDatabase::setParameters(const DBParameters &params)
{
        StLock<Mutex> _(common());
    makeUnlocked();
        common().mParams = params;
    common().invalidateBlob();          // invalidate old blobs
    activity();                         // (also resets the timeout timer)
        secdebug("KCdb", "%p common %p(%s) set params=(%u,%u)",
                this, &common(), dbName(), params.idleTimeout, params.lockOnSleep);
}


//
// Retrieve database parameters
//
void KeychainDatabase::getParameters(DBParameters &params)
{
        StLock<Mutex> _(common());
    makeUnlocked();
        params = common().mParams;
    //activity();               // getting parameters does not reset the idle timer
}


//
// RIGHT NOW, database ACLs are attached to the database.
// This will soon move upstairs.
//
SecurityServerAcl &KeychainDatabase::acl()
{
        return *this;
}


//
// Intercept ACL change requests and reset blob validity
//
void KeychainDatabase::instantiateAcl()
{
        StLock<Mutex> _(common());
        makeUnlocked();
}

void KeychainDatabase::changedAcl()
{
        StLock<Mutex> _(common());
        version = 0;
}


//
// Check an incoming DbBlob for basic viability
//
void KeychainDatabase::validateBlob(const DbBlob *blob)
{
    // perform basic validation on the blob
        assert(blob);
        blob->validate(CSSMERR_APPLEDL_INVALID_DATABASE_BLOB);
        switch (blob->version()) {
#if defined(COMPAT_OSX_10_0)
                case DbBlob::version_MacOS_10_0:
                        break;
#endif
                case DbBlob::version_MacOS_10_1:
                        break;
                default:
                        CssmError::throwMe(CSSMERR_APPLEDL_INCOMPATIBLE_DATABASE_BLOB);
        }
}


//
// Debugging support
//
#if defined(DEBUGDUMP)

void KeychainDbCommon::dumpNode()
{
        PerSession::dumpNode();
        uint32 sig; memcpy(&sig, &mIdentifier.signature(), sizeof(sig));
        Debug::dump(" %s[%8.8x]", mIdentifier.dbName(), sig);
        if (isLocked()) {
                Debug::dump(" locked");
        } else {
                time_t whenTime = time_t(when());
                Debug::dump(" unlocked(%24.24s/%.2g)", ctime(&whenTime),
                        (when() - Time::now()).seconds());
        }
        Debug::dump(" params=(%u,%u)", mParams.idleTimeout, mParams.lockOnSleep);
}

void KeychainDatabase::dumpNode()
{
        PerProcess::dumpNode();
        Debug::dump(" %s vers=%u",
                mValidData ? " data" : " nodata", version);
        if (mBlob) {
                uint32 sig; memcpy(&sig, &mBlob->randomSignature, sizeof(sig));
                Debug::dump(" blob=%p[%8.8x]", mBlob, sig);
        } else {
                Debug::dump(" noblob");
        }
}

#endif //DEBUGDUMP


//
// DbCommon basic features
//
KeychainDbCommon::KeychainDbCommon(Session &ssn, const DbIdentifier &id)
        : LocalDbCommon(ssn), sequence(0), version(1), mIdentifier(id),
      mIsLocked(true), mValidParams(false), mLoginKeychain(false)
{
    // match existing DbGlobal or create a new one
        {
        Server &server = Server::active();
        StLock<Mutex> _(server);
        if (KeychainDbGlobal *dbglobal =
                server.findFirst<KeychainDbGlobal, const DbIdentifier &>(&KeychainDbGlobal::identifier, identifier())) {
            parent(*dbglobal);
            secdebug("KCdb", "%p linking to existing DbGlobal %p", this, dbglobal);
        } else {
            // DbGlobal not present; make a new one
            parent(*new KeychainDbGlobal(identifier()));
            secdebug("KCdb", "%p linking to new DbGlobal %p", this, &global());
        }

        // link lifetime to the Session
        session().addReference(*this);
        
        if (strcasestr(id.dbName(), "login.keychain") != NULL) {
            mLoginKeychain = true;
        }
    }

    if (mLoginKeychain && !session().keybagGetState(session_keybag_loaded)) {
        service_context_t context = session().get_current_service_context();
        if (service_client_kb_load(&context) == 0) {
            session().keybagSetState(session_keybag_loaded);
        }
    }
}

KeychainDbCommon::~KeychainDbCommon()
{
        SECURITYD_KEYCHAIN_RELEASE(this, (char*)this->dbName());

        // explicitly unschedule ourselves
        Server::active().clearTimer(this);
    if (mLoginKeychain) {
        session().keybagClearState(session_keybag_unlocked);
    }
}

KeychainDbGlobal &KeychainDbCommon::global() const
{
        return parent<KeychainDbGlobal>();
}


void KeychainDbCommon::select()
{ this->ref(); }

void KeychainDbCommon::unselect()
{ this->unref(); }



void KeychainDbCommon::makeNewSecrets()
{
        // we already have a master key (right?)
        assert(hasMaster());

        // tell crypto core to generate the use keys
        DatabaseCryptoCore::generateNewSecrets();
        
        // we're now officially "unlocked"; set the timer
        setUnlocked();
}


//
// All unlocking activity ultimately funnels through this method.
// This unlocks a DbCommon using the secrets setup in its crypto core
// component, and performs all the housekeeping needed to represent
// the state change.
// Returns true if unlock was successful, false if it failed due to
// invalid/insufficient secrets. Throws on other errors.
//
bool KeychainDbCommon::unlockDb(DbBlob *blob, void **privateAclBlob)
{
        try {
                // Tell the cryptocore to (try to) decode itself. This will fail
                // in an astonishing variety of ways if the passphrase is wrong.
                assert(hasMaster());
                decodeCore(blob, privateAclBlob);
                secdebug("KCdb", "%p unlock successful", this);
        } catch (...) {
                secdebug("KCdb", "%p unlock failed", this);
                return false;
        }
        
        // get the database parameters only if we haven't got them yet
        if (!mValidParams) {
                mParams = blob->params;
                n2hi(mParams.idleTimeout);
                mValidParams = true;    // sticky
        }

        bool isLocked = mIsLocked;
        
        setUnlocked();          // mark unlocked
        
        if (isLocked) {
                // broadcast unlock notification, but only if we were previously locked
                notify(kNotificationEventUnlocked);
                SECURITYD_KEYCHAIN_UNLOCK(this, (char*)this->dbName());
        }
    return true;
}

void KeychainDbCommon::setUnlocked()
{
        session().addReference(*this);  // active/held
        mIsLocked = false;                              // mark unlocked
        activity();                                             // set timeout timer
}


void KeychainDbCommon::lockDb()
{
    bool lock = false;
    {
        StLock<Mutex> _(*this);
        if (!isLocked()) {
            DatabaseCryptoCore::invalidate();
            notify(kNotificationEventLocked);
            SECURITYD_KEYCHAIN_LOCK(this, (char*)this->dbName());
            Server::active().clearTimer(this);

            mIsLocked = true;           // mark locked
            lock = true;
            
            // this call may destroy us if we have no databases anymore
            session().removeReference(*this);
        }
    }
    
    if (mLoginKeychain && lock) {
        service_context_t context = session().get_current_service_context();
        service_client_kb_lock(&context);
        session().keybagClearState(session_keybag_unlocked);
    }
}


DbBlob *KeychainDbCommon::encode(KeychainDatabase &db)
{
    assert(!isLocked());        // must have been unlocked by caller
    
    // export database ACL to blob form
    CssmData pubAcl, privAcl;
    db.acl().exportBlob(pubAcl, privAcl);
    
    // tell the cryptocore to form the blob
    DbBlob form;
    form.randomSignature = identifier();
    form.sequence = sequence;
    form.params = mParams;
        h2ni(form.params.idleTimeout);
        
        assert(hasMaster());
    DbBlob *blob = encodeCore(form, pubAcl, privAcl);
    
    // clean up and go
    db.acl().allocator.free(pubAcl);
    db.acl().allocator.free(privAcl);
        return blob;
}


//
// Perform deferred lock processing for a database.
//
void KeychainDbCommon::action()
{
        secdebug("KCdb", "common %s(%p) locked by timer", dbName(), this);
        lockDb();
}

void KeychainDbCommon::activity()
{
    if (!isLocked()) {
                secdebug("KCdb", "setting DbCommon %p timer to %d",
                        this, int(mParams.idleTimeout));
                Server::active().setTimer(this, Time::Interval(int(mParams.idleTimeout)));
        }
}

void KeychainDbCommon::sleepProcessing()
{
        secdebug("KCdb", "common %s(%p) sleep-lock processing", dbName(), this);
        StLock<Mutex> _(*this);
        if (mParams.lockOnSleep)
                lockDb();
}

void KeychainDbCommon::lockProcessing()
{
        lockDb();
}


//
// We consider a keychain to belong to the system domain if it resides
// in /Library/Keychains. That's not exactly fool-proof, but we don't
// currently have any internal markers to interrogate.
//
bool KeychainDbCommon::belongsToSystem() const
{
        if (const char *name = this->dbName())
                return !strncmp(name, "/Library/Keychains/", 19);
        return false;
}


//
// Keychain global objects
//
KeychainDbGlobal::KeychainDbGlobal(const DbIdentifier &id)
        : mIdentifier(id)
{
}

KeychainDbGlobal::~KeychainDbGlobal()
{
        secdebug("KCdb", "DbGlobal %p destroyed", this);
}