bool CryptoManager::decrypt(ISC_STATUS* sv, Ods::pag* page)
{
// Code calling us is not ready to process exceptions correctly
// Therefore use old (status vector based) method
try
{
if (page->pag_flags & Ods::crypted_page)
{
if (!cryptPlugin)
{
// We are invoked from shared cache manager, i.e. no valid attachment in tdbb
// Therefore create system temporary attachment like in crypt thread to be able to work with locks
UserId user;
user.usr_user_name = "(Crypt plugin loader)";
Jrd::Attachment* const attachment = Jrd::Attachment::create(&dbb);
RefPtr<SysAttachment> jAtt(new SysAttachment(attachment));
attachment->att_interface = jAtt;
attachment->att_filename = dbb.dbb_filename;
attachment->att_user = &user;
BackgroundContextHolder tdbb(&dbb, attachment, sv, FB_FUNCTION);
// Lock crypt state
takeStateLock(tdbb);
Header hdr(tdbb, LCK_read);
crypt = hdr->hdr_flags & Ods::hdr_encrypted;
process = hdr->hdr_flags & Ods::hdr_crypt_process;
if (crypt || process)
{
loadPlugin(hdr->hdr_crypt_plugin);
}
if (!cryptPlugin)
{
(Arg::Gds(isc_decrypt_error)).raise();
return false;
}
}
LocalStatus status;
cryptPlugin->decrypt(&status, dbb.dbb_page_size - sizeof(Ods::pag), &page[1], &page[1]);
if (!status.isSuccess())
{
memcpy(sv, status.get(), sizeof(ISC_STATUS_ARRAY));
return false;
}
}
return true;
}
catch (const Exception& ex)
{
ex.stuff_exception(sv);
}
return false;
}
void CryptoManager::blockingAstChangeCryptState()
{
AsyncContextHolder tdbb(&dbb, FB_FUNCTION);
fb_assert(stateLock);
LCK_release(tdbb, stateLock);
needLock = true;
}
int Database::blocking_ast_sweep(void* ast_object)
{
Database* dbb = static_cast<Database*>(ast_object);
AsyncContextHolder tdbb(dbb, FB_FUNCTION);
if ((dbb->dbb_flags & DBB_sweep_starting) && !(dbb->dbb_flags & DBB_sweep_in_progress))
{
dbb->dbb_flags &= ~DBB_sweep_starting;
LCK_release(tdbb, dbb->dbb_sweep_lock);
}
return 0;
}
int GlobalRWLock::blocking_ast_cached_lock(void* ast_object)
{
GlobalRWLock* globalRWLock = static_cast<GlobalRWLock*>(ast_object);
try
{
Firebird::MutexLockGuard counterGuard(globalRWLock->counterMutex);
if (!globalRWLock->cachedLock)
return 0;
Database* dbb = globalRWLock->cachedLock->lck_dbb;
AstContextHolder tdbb(dbb);
if (globalRWLock->cachedLock)
globalRWLock->blockingAstHandler(tdbb);
}
catch (const Firebird::Exception&)
{} // no-op
return 0;
}
void CryptoManager::cryptThread()
{
ISC_STATUS_ARRAY status_vector;
try
{
// Try to take crypt mutex
// If can't take that mutex - nothing to do, cryptThread already runs in our process
MutexEnsureUnlock guard(cryptThreadMtx, FB_FUNCTION);
if (!guard.tryEnter())
{
return;
}
// establish context
UserId user;
user.usr_user_name = "(Crypt thread)";
Jrd::Attachment* const attachment = Jrd::Attachment::create(&dbb);
RefPtr<SysAttachment> jAtt(new SysAttachment(attachment));
attachment->att_interface = jAtt;
attachment->att_filename = dbb.dbb_filename;
attachment->att_user = &user;
BackgroundContextHolder tdbb(&dbb, attachment, status_vector, FB_FUNCTION);
tdbb->tdbb_quantum = SWEEP_QUANTUM;
ULONG lastPage = getLastPage(tdbb);
ULONG runpage = 1;
Stack<ULONG> pages;
// Take exclusive threadLock
// If can't take that lock - nothing to do, cryptThread already runs somewhere
if (!LCK_lock(tdbb, threadLock, LCK_EX, LCK_NO_WAIT))
{
return;
}
bool lckRelease = false;
try
{
do
{
// Check is there some job to do
while ((runpage = currentPage.exchangeAdd(+1)) < lastPage)
{
// forced terminate
if (down)
{
break;
}
// nbackup state check
if (dbb.dbb_backup_manager && dbb.dbb_backup_manager->getState() != nbak_state_normal)
{
if (currentPage.exchangeAdd(-1) >= lastPage)
{
// currentPage was set to last page by thread, closing database
break;
}
THD_sleep(100);
continue;
}
// scheduling
if (--tdbb->tdbb_quantum < 0)
{
JRD_reschedule(tdbb, SWEEP_QUANTUM, true);
}
// writing page to disk will change it's crypt status in usual way
WIN window(DB_PAGE_SPACE, runpage);
Ods::pag* page = CCH_FETCH(tdbb, &window, LCK_write, pag_undefined);
if (page && page->pag_type <= pag_max &&
(bool(page->pag_flags & Ods::crypted_page) != crypt) &&
Ods::pag_crypt_page[page->pag_type])
{
CCH_MARK(tdbb, &window);
pages.push(runpage);
}
CCH_RELEASE_TAIL(tdbb, &window);
// sometimes save currentPage into DB header
++runpage;
if ((runpage & 0x3FF) == 0)
{
writeDbHeader(tdbb, runpage, pages);
}
}
// At this moment of time all pages with number < lastpage
// are guaranteed to change crypt state. Check for added pages.
lastPage = getLastPage(tdbb);
// forced terminate
if (down)
{
break;
}
} while (runpage < lastPage);
// Finalize crypt
if (!down)
{
writeDbHeader(tdbb, 0, pages);
}
// Release exclusive lock on StartCryptThread
lckRelease = true;
LCK_release(tdbb, threadLock);
}
catch (const Exception&)
{
try
{
if (!lckRelease)
{
// try to save current state of crypt thread
if (!down)
{
writeDbHeader(tdbb, runpage, pages);
}
// Release exclusive lock on StartCryptThread
LCK_release(tdbb, threadLock);
}
}
catch (const Exception&)
{ }
throw;
}
}
catch (const Exception& ex)
{
// Error during context creation - we can't even release lock
iscLogException("Crypt thread:", ex);
}
}
