Bitlocker Full Disk Encryption

Mgr. Guruprasad Bidare Venkatesh

Master's thesis

Abstract:

V současném moderním světě informační éry, informační bezpečnosti hraje zásadní roli při ochraně důvěrnosti citlivých osob informace. Bezpečnost informací hraje důležitou roli při zajišťování informací jako schopnosti útoku a protivníka se v průběhu let značně zvýšily. Bezpečnost jakýkoli informační systém může být klasifikován jako bezpečnost během komunikace / doprava, bezpečnost při zpracování a zabezpečení během úložný prostor. Přestože se první dvě kategorie zabývají z velké části výzkumní pracovníci v oblasti bezpečnosti chyběli zlepšení v důsledku několika otázek. Ochrana zabezpečení úložiště data v klidu byla rozhodující kvůli množství citlivých informací který je uložen a přístupný protivníkům. Tam jsou softwarové nástroje pro zabezpečení zabezpečení uložených informací. Tato práce hodnotí technologii nástroje Window's BitLocker pro šifrování celého disku (FDE) a hardwarové šifrování Pohony (SED) [4, 5]. Nástroj BitLocker je studován a popsán spolu s jeho funkcemi a dostupnými možnostmi šifrování systému, BitLocker-on-the-Go a eDrive. Zahrnuje proces autentizace a způsoby správy klíčů, které používá nástroj BitLocker pro Windows10 [7, 8, 9]. Práce také zkoumá vlastní šifrování Zařízení (SED) podporující standard Opal s Windows (Bit- Locker eDrive) [2]. Modely ohrožení a útoky na šifrování disku v kontextu editačního prostředí BitLocker jsou také analyzovány v práci [4, 5, 6]. Hodnotí nástroj otevřeného zdroje, který umožňuje přístup k Bit- Formát disku Locker v systému Linux nebo Windows.

Abstract:

In the current modern world of information era, Information security plays a vital role in protecting the confidentiality of the sensitive information. The information security has a major role to play in securing the information as the attack surface and adversary capabilities have increased enormously over the years. The security of any information system can be classified as security during communication/ transport, security during processing and security during storage. Even though the first two categories have been dealt with to a large extent by security researchers, the latter has been lacking the enhancement due to several issues. The storage security protecting the data at rest has been crucial due to its amount of sensitive information that is being stored and accessible to the adversaries. There are software tools for providing the security for stored information. This thesis reviews the technology of Window’s BitLocker tool for Full Disk Encryption (FDE) and hardware based Self Encrypting Drives (SEDs) [4, 5]. The BitLocker tool is studied and described along with its features and available options for system encryption, BitLocker-on-the-Go and eDrive. It includes the authentication process and the key management methods being used by BitLocker for Windows10 [7, 8, 9]. The thesis also investigates the Self Encrypting Devices (SEDs) supporting the Opal standard with Windows (Bit- Locker eDrive) [2]. The threat models and attacks on disk encryption in the BitLocker edrive context are also analyzed in the thesis [4, 5, 6]. It evaluates the open source tool that enables the access to the Bit- Locker drive format in Linux or Windows. iv

Keywords

Storage Security, BitLocker, Full Disk Encryption (FDE), Self Encrypting Drives (SED), threat model, attacks, Authentication, Key Management, Opal standard, open source tool. • Storage Security, Storage security is a branch of security technology which aims at providing security to data at rest. • Full Disk Encryption, FDE, Full Disk Encryption (FDE) is the technology to encrypt the entire disk content including the Operating System partition. • Self Encrypting Drives, SED, Self Encrypting Drives (SEDs) are special type of hard drives with in-built hardware based encryption module. • Trusted Computing Group, TCG, TCG is the international technical forum formulating the specifications for storage security technology. • Opal, Opal is the storage security specification for SEDs to provide security for data at rest formulated by TCG. • BitLocker, The BitLocker is a software tool fromWindows Operating System to provide the storage security for data in hard drives/Removable Drives. • Serial Advanced Technology Attachment, SATA, SATA is the high speed serial communication technology to connect a hard drive with a Central Processing Unit (CPU) of a system. • Symmetric Encryption, A type of encryption where in the same key will used for encryption and decryption and pre-shared between sender and receiver. v • Block Modes of encryption -Atype of encryption where in source data is encrypted in terms of blocks of bits viz., 128bits, 256bit or 512bits etc, . • Cipher Block Chain Mode, CBC mode, A type of encryption mode wherein encryption of current block of plain text depends on the previous cipher text block . The first block of plain text will be encrypted using a prefixed InitializationVector (IV) bits. • Xor-encrypt-xor (XEX), A type of tweakable encryption mode for disk encryption, wherein a combination of the sector address and index of the block within the sector are used for encryption. • XEX-based tweaked-code book mode with cipher text stealing (XTS), Cipher text stealing provides XEX support for sectors with size not divisible by block size, for example, 520-byte sectors and 16-byte blocks. • CBC XTS, A type of encryption mode which is a combination of CBC encryption mode with XTS features. • Basic Input Output System (BIOS), BIOS is a program running from a non-volatile memory responsible for initializing the system hardware and providing its essential interface to Operating System. • Unified Extensible Firmware Interface (UEFI), UEFI is an advanced version of BIOS which supports more number of peripherals, provides option of dynamic programming through external interface with user friendly graphical features.

Language used: English

Date on which the thesis was submitted / produced: 14. 12. 2017

Thesis defence

• Date of defence: 2. 2. 2018
• Supervisor: Ing. Milan Brož
• Reader: RNDr. Petr Švenda, Ph.D.

Masaryk University

Faculty of Informatics

Master programme / field:
Informatics / Information Technology Security (eng.)