Method authenticate

src/auth/SecurityDatabase/LegacyServer.cpp:307–397

 */

int SecurityDatabaseServer::authenticate(CheckStatusWrapper* status, IServerBlock* sBlock,
	IWriter* authBlock)
{
	status->init();

	try
	{
		const char* user = sBlock->getLogin();
		if (!user)
		{
			HANDSHAKE_DEBUG(fprintf(stderr, "LegacyServer (nologin) %d\n", IAuth::AUTH_CONTINUE));
			return IAuth::AUTH_CONTINUE;
		}
		string login(user);

		unsigned length;
		const unsigned char* data = sBlock->getData(&length);
		if (!(data && length))
		{
			HANDSHAKE_DEBUG(fprintf(stderr, "LegacyServer (nopw) %d\n", IAuth::AUTH_MORE_DATA));
			return IAuth::AUTH_MORE_DATA;
		}

		bool found = false;
		char pw1[MAX_LEGACY_PASSWORD_LENGTH + 1];
		PathName secureDbName;
		{ // instance scope
			// Get database block from cache
			CachedSecurityDatabase::Instance instance;
			instances->getInstance(iParameter, instance);

			secureDbName = instance->secureDbName;
			if (!instance->secDb)
				instance->secDb = FB_NEW SecurityDatabase(instance->secureDbName);

			user_name uname;		// user name buffer
			login.copyTo(uname, sizeof uname);
			user_record user_block;		// user record
			found = instance->secDb->lookup(uname, &user_block);
			fb_utils::copy_terminate(pw1, user_block.password, MAX_LEGACY_PASSWORD_LENGTH + 1);
		}
		if (!found)
		{
			HANDSHAKE_DEBUG(fprintf(stderr, "LegacyServer (badlogin) %d\n", IAuth::AUTH_CONTINUE));
			return IAuth::AUTH_CONTINUE;
		}

		string storedHash(pw1, MAX_LEGACY_PASSWORD_LENGTH);
		storedHash.rtrim();
		storedHash.recalculate_length();

		string passwordEnc;
		passwordEnc.assign(data, length);

		string newHash;
		LegacyHash::hash(newHash, login, passwordEnc, storedHash);
		if (newHash != storedHash)
		{