Backported fix for CORE-5213

src/jrd/CryptoManager.cpp

@@ -63,6 +63,17 @@ namespace {
 		return 0;
 	}
 
+	const UCHAR CRYPT_RELEASE = LCK_SR;
+	const UCHAR CRYPT_NORMAL = LCK_PR;
+	const UCHAR CRYPT_CHANGE = LCK_PW;
+	const UCHAR CRYPT_INIT = LCK_EX;
+
+	const int MAX_PLUGIN_NAME_LEN = 31;
+}
+
+
+namespace Jrd {
+
 	class Header
 	{
 	protected:
@@ -88,7 +99,7 @@ namespace {
 
 		// This routine is getting clumplets from header page but is not ready to handle continuation
 		// Fortunately, modern pages of size 4k and bigger can fit everything on one page.
-		void getClumplets(ClumpletWriter& writer)
+		void getClumplets(ClumpletWriter& writer) const
 		{
 			writer.reset(header->hdr_data, header->hdr_end - HDR_SIZE);
 		}
@@ -233,17 +244,6 @@ namespace {
 		AutoPtr<UCHAR, ArrayDelete<UCHAR> > buffer;
 	};
 
-	const UCHAR CRYPT_RELEASE = LCK_SR;
-	const UCHAR CRYPT_NORMAL = LCK_PR;
-	const UCHAR CRYPT_CHANGE = LCK_PW;
-	const UCHAR CRYPT_INIT = LCK_EX;
-
-	const int MAX_PLUGIN_NAME_LEN = 31;
-}
-
-
-namespace Jrd {
-
 	CryptoManager::CryptoManager(thread_db* tdbb)
 		: PermanentStorage(*tdbb->getDatabase()->dbb_permanent),
 		  sync(this),
@@ -353,6 +353,9 @@ namespace Jrd {
 					(Arg::Gds(isc_bad_crypt_key) << keyName).raise();
 			}
 		}
+
+		if (flags & CRYPT_HDR_INIT)
+			checkDigitalSignature(hdr);
 	}
 
 	void CryptoManager::loadPlugin(const char* pluginName)
@@ -533,6 +536,8 @@ namespace Jrd {
 			header->hdr_crypt_page = 1;
 			header->hdr_flags |= Ods::hdr_crypt_process;
 			process = true;
+
+			digitalySignDatabase(hdr);
 		}
 		catch (const Exception&)
 		{
@@ -870,6 +875,8 @@ namespace Jrd {
 				hdr.setClumplets(hc);
 			}
 		}
+
+		digitalySignDatabase(hdr);
 	}
 
 	bool CryptoManager::read(thread_db* tdbb, FbStatusVector* sv, Ods::pag* page, IOCallback* io)
@@ -1177,4 +1184,97 @@ namespace Jrd {
 		st.check();
 	}
 
+	void CryptoManager::addClumplet(string& signature, ClumpletReader& block, UCHAR tag)
+	{
+		if (block.find(tag))
+		{
+			string tmp;
+			block.getString(tmp);
+			signature += ' ';
+			signature += tmp;
+		}
+	}
+
+	void CryptoManager::calcDigitalSignature(string& signature, const Header& hdr)
+	{
+	   /*
+		We use the following items to calculate digital signature (hash of encrypted string)
+		for database:
+			hdr_flags & (hdr_crypt_process | hdr_encrypted)
+			hdr_crypt_page
+			hdr_crypt_plugin
+			HDR_crypt_key
+			HDR_crypt_hash
+		*/
+
+		signature.printf("%d %d %d %s",
+						  hdr->hdr_flags & Ods::hdr_crypt_process ? 1 : 0,
+							 hdr->hdr_flags & Ods::hdr_encrypted ? 1 : 0,
+								hdr->hdr_crypt_page,
+								   hdr->hdr_crypt_plugin);
+
+		ClumpletWriter hc(ClumpletWriter::UnTagged, hdr->hdr_page_size);
+		hdr.getClumplets(hc);
+
+		addClumplet(signature, hc, Ods::HDR_crypt_key);
+		addClumplet(signature, hc, Ods::HDR_crypt_hash);
+
+		const unsigned QUANTUM = 16;
+		signature += string(QUANTUM - 1, '$');
+		unsigned len = signature.length();
+		len &= ~(QUANTUM - 1);
+
+		loadPlugin(hdr->hdr_crypt_plugin);
+
+		string enc;
+		FbLocalStatus sv;
+		cryptPlugin->encrypt(&sv, len, signature.c_str(), enc.getBuffer(len));
+		if (sv->getState() & IStatus::STATE_ERRORS)
+			Arg::StatusVector(&sv).raise();
+
+		Sha1::hashBased64(signature, enc);
+	}
+
+
+	void CryptoManager::digitalySignDatabase(CchHdr& hdr)
+	{
+		ClumpletWriter hc(ClumpletWriter::UnTagged, hdr->hdr_page_size);
+		hdr.getClumplets(hc);
+
+		bool wf = hc.find(Ods::HDR_crypt_checksum);
+		hc.deleteWithTag(Ods::HDR_crypt_checksum);
+
+		if (hdr->hdr_flags & (Ods::hdr_crypt_process | Ods::hdr_encrypted))
+		{
+			wf = true;
+			string signature;
+			calcDigitalSignature(signature, hdr);
+			hc.insertString(Ods::HDR_crypt_checksum, signature);
+		}
+
+		if (wf)
+			hdr.setClumplets(hc);
+	}
+
+	void CryptoManager::checkDigitalSignature(const Header& hdr)
+	{
+		// if (hdr->hdr_flags & (Ods::hdr_crypt_process | Ods::hdr_encrypted))
+		// Restricted check to ensure compatibility with 3.0.0 databases - only for active crypt process
+		if (hdr->hdr_flags & Ods::hdr_crypt_process)
+		{
+			const char* message = "Invalid or missing checksum of encrypted database";
+
+			ClumpletWriter hc(ClumpletWriter::UnTagged, hdr->hdr_page_size);
+			hdr.getClumplets(hc);
+			if (!hc.find(Ods::HDR_crypt_checksum))
+				(Arg::Gds(isc_random) << message).raise();
+
+			string sig1, sig2;
+			hc.getString(sig1);
+			calcDigitalSignature(sig2, hdr);
+			if (sig1 != sig2)
+				(Arg::Gds(isc_random) << message).raise();
+		}
+	}
+
 } // namespace Jrd

src/jrd/CryptoManager.h

@@ -46,7 +46,15 @@
 class Config;
 
 namespace Ods {
-	struct pag;
+
+struct pag;
+
+}
+
+namespace Firebird {
+
+class ClumpletReader;
+
 }
 
 namespace Jrd {
@@ -363,6 +371,11 @@ private:
 	static const unsigned CRYPT_HDR_INIT =		0x01;
 	static const unsigned CRYPT_HDR_NOWAIT =	0x02;
 
+	void addClumplet(Firebird::string& value, Firebird::ClumpletReader& block, UCHAR tag);
+	void calcDigitalSignature(Firebird::string& signature, const class Header& hdr);
+	void digitalySignDatabase(class CchHdr& hdr);
+	void checkDigitalSignature(const class Header& hdr);
+
 	BarSync sync;
 	Firebird::MetaName keyName;
 	ULONG currentPage;

src/jrd/ods.h

@@ -426,7 +426,7 @@ const UCHAR HDR_root_file_name		= 1;	// Original name of root file
 const UCHAR HDR_file				= 2;	// Secondary file
 const UCHAR HDR_last_page			= 3;	// Last logical page number of file
 const UCHAR HDR_sweep_interval		= 4;	// Transactions between sweeps
-const UCHAR HDR_password_file_key	= 5;	// Key to compare to password db
+const UCHAR HDR_crypt_checksum		= 5;	// Checksum of critical crypt parameters
 const UCHAR HDR_difference_file		= 6;	// Delta file that is used during backup lock
 const UCHAR HDR_backup_guid			= 7;	// UID generated on each switch into backup mode
 const UCHAR HDR_crypt_key			= 8;	// Name of a key used to crypt database
@@ -437,7 +437,6 @@ const UCHAR HDR_max					= 10;	// Maximum HDR_clump value
 
 const USHORT hdr_active_shadow		= 0x1;		// 1	file is an active shadow file
 const USHORT hdr_force_write		= 0x2;		// 2	database is forced write
-// const USHORT hdr_no_checksums	= 0x4;		// 4	don't calculate checksums, not used since ODS 12
 const USHORT hdr_crypt_process		= 0x4;		// 4	Encryption status is changing now
 const USHORT hdr_no_reserve			= 0x8;		// 8	don't reserve space for versions
 const USHORT hdr_SQL_dialect_3		= 0x10;		// 16	database SQL dialect 3