 | Parts of this article (those related to status and content of IEEE 1619.2 (published in 2010)) need to be updated.(March 2024) |
Institute of Electrical and Electronics Engineers (IEEE) standardization project for encryption of stored data, but more generically refers to the Security in Storage Working Group (SISWG), which includes a family of standards for protection of stored data and for the corresponding cryptographic key management.
SISWG oversees work on the following standards:
The base IEEE 1619 Standard Architecture for Encrypted Shared Storage Media uses the XTS-Advanced Encryption Standard (XEX-based Tweaked CodeBook mode (TCB) with ciphertext stealing (CTS); [1] the proper name should be XTC (XEX TCB CTS), but that acronym is already used to denote the drug ecstasy).
The P1619.1 Authenticated Encryption with Length Expansion for Storage Devices uses the following algorithms:
The P1619.2 Standard for Wide-Block Encryption for Shared Storage Media has proposed algorithms including:
The P1619.3 Standard for Key Management Infrastructure for Cryptographic Protection of Stored Data defines a system for managing encryption data at rest security objects which includes architecture, namespaces, operations, messaging and transport.
P1619 also standardized the key backup in the XML format.
An encryption algorithm used for data storage has to support independent encryption and decryption of portions of data. So-called narrow-block algorithms operate on relatively small portions of data, while the wide-block algorithms encrypt or decrypt a whole sector. Narrow-block algorithms have the advantage of more efficient hardware implementation. On the other hand, smaller block size provides finer granularity for data modification attacks. There is no standardized "acceptable granularity"; however, for example, the possibility of data modification with the granularity of one bit (bit-flipping attack) is generally considered unacceptable.
For these reasons, the working group selected the narrow-block (128 bits) encryption with no authentication in the standard P1619, assuming that the added efficiency warrants the additional risk. But recognizing that wide-block encryption might be useful in some cases, another project P1619.2 has been started to study the usage of wide-block encryption.
The project is maintained by the IEEE Security in Storage Working Group (SISWG). Both the disk storage standard P1619 (sometimes called P1619.0) and the tape storage standard P1619.1 were standardized in December 2007. [2]
A discussion was ongoing[ when? ] on standardization of the wide-block encryption for disk drives, like CMC and EME as P1619.2, and on key management as P1619.3.
From 2004 to 2006, drafts of the P1619 standards used the Advanced Encryption Standard (AES) in LRW mode. In the 30 Aug 2006 Archived 11 March 2007 at the Wayback Machine meeting of the SISWG, a straw poll showed that most members would not approve P1619 as it was. Consequently, LRW-AES has been replaced by the XEX-AES tweakable block cipher in P1619.0 Draft 7 (and renamed to XTS-AES in Draft 11). Some members of the group found it non-trivial to abandon LRW, because it had been available for public peer-review for many years (unlike most of the newly suggested variants). The issues of LRW were:
In cryptography, a block cipher is a deterministic algorithm that operates on fixed-length groups of bits, called blocks. Block ciphers are the elementary building blocks of many cryptographic protocols. They are ubiquitous in the storage and exchange of data, where such data is secured and authenticated via encryption.
In cryptography, a cipher is an algorithm for performing encryption or decryption—a series of well-defined steps that can be followed as a procedure. An alternative, less common term is encipherment. To encipher or encode is to convert information into cipher or code. In common parlance, "cipher" is synonymous with "code", as they are both a set of steps that encrypt a message; however, the concepts are distinct in cryptography, especially classical cryptography.
In cryptography, Triple DES, officially the Triple Data Encryption Algorithm, is a symmetric-key block cipher, which applies the DES cipher algorithm three times to each data block. The 56-bit key of the Data Encryption Standard (DES) is no longer considered adequate in the face of modern cryptanalytic techniques and supercomputing power; Triple DES increases the effective security to 112 bits. A CVE released in 2016, CVE-2016-2183, disclosed a major security vulnerability in the DES and 3DES encryption algorithms. This CVE, combined with the inadequate key size of 3DES, led to NIST deprecating 3DES in 2019 and disallowing all uses by the end of 2023. It has been replaced with the more secure, more robust AES.
Symmetric-key algorithms are algorithms for cryptography that use the same cryptographic keys for both the encryption of plaintext and the decryption of ciphertext. The keys may be identical, or there may be a simple transformation to go between the two keys. The keys, in practice, represent a shared secret between two or more parties that can be used to maintain a private information link. The requirement that both parties have access to the secret key is one of the main drawbacks of symmetric-key encryption, in comparison to public-key encryption. However, symmetric-key encryption algorithms are usually better for bulk encryption. With exception of the one-time pad they have a smaller key size, which means less storage space and faster transmission. Due to this, asymmetric-key encryption is often used to exchange the secret key for symmetric-key encryption.
In cryptography, an initialization vector (IV) or starting variable is an input to a cryptographic primitive being used to provide the initial state. The IV is typically required to be random or pseudorandom, but sometimes an IV only needs to be unpredictable or unique. Randomization is crucial for some encryption schemes to achieve semantic security, a property whereby repeated usage of the scheme under the same key does not allow an attacker to infer relationships between segments of the encrypted message. For block ciphers, the use of an IV is described by the modes of operation.
In cryptography, a block cipher mode of operation is an algorithm that uses a block cipher to provide information security such as confidentiality or authenticity. A block cipher by itself is only suitable for the secure cryptographic transformation of one fixed-length group of bits called a block. A mode of operation describes how to repeatedly apply a cipher's single-block operation to securely transform amounts of data larger than a block.
In cryptography, a weak key is a key, which, used with a specific cipher, makes the cipher behave in some undesirable way. Weak keys usually represent a very small fraction of the overall keyspace, which usually means that, a cipher key made by random number generation is very unlikely to give rise to a security problem. Nevertheless, it is considered desirable for a cipher to have no weak keys. A cipher with no weak keys is said to have a flat, or linear, key space.
Authenticated Encryption (AE) is an encryption scheme which simultaneously assures the data confidentiality and authenticity. Examples of encryption modes that provide AE are GCM, CCM.
Encryption software is software that uses cryptography to prevent unauthorized access to digital information. Cryptography is used to protect digital information on computers as well as the digital information that is sent to other computers over the Internet.
Disk encryption is a special case of data at rest protection when the storage medium is a sector-addressable device. This article presents cryptographic aspects of the problem. For an overview, see disk encryption. For discussion of different software packages and hardware devices devoted to this problem, see disk encryption software and disk encryption hardware.
FreeOTFE is a discontinued open source computer program for on-the-fly disk encryption (OTFE). On Microsoft Windows, and Windows Mobile, it can create a virtual drive within a file or partition, to which anything written is automatically encrypted before being stored on a computer's hard or USB drive. It is similar in function to other disk encryption programs including TrueCrypt and Microsoft's BitLocker.
In cryptography, Galois/Counter Mode (GCM) is a mode of operation for symmetric-key cryptographic block ciphers which is widely adopted for its performance. GCM throughput rates for state-of-the-art, high-speed communication channels can be achieved with inexpensive hardware resources.
BestCrypt, developed by Jetico, is a commercial disk encryption app available for Windows, Linux, macOS and Android.
This is a technical feature comparison of different disk encryption software.
In cryptography, key wrap constructions are a class of symmetric encryption algorithms designed to encapsulate (encrypt) cryptographic key material. The Key Wrap algorithms are intended for applications such as protecting keys while in untrusted storage or transmitting keys over untrusted communications networks. The constructions are typically built from standard primitives such as block ciphers and cryptographic hash functions.
dm-crypt is a transparent block device encryption subsystem in Linux kernel versions 2.6 and later and in DragonFly BSD. It is part of the device mapper (dm) infrastructure, and uses cryptographic routines from the kernel's Crypto API. Unlike its predecessor cryptoloop, dm-crypt was designed to support advanced modes of operation, such as XTS, LRW and ESSIV, in order to avoid watermarking attacks. In addition to that, dm-crypt addresses some reliability problems of cryptoloop.
In cryptography, format-preserving encryption (FPE), refers to encrypting in such a way that the output is in the same format as the input. The meaning of "format" varies. Typically only finite sets of characters are used; numeric, alphabetic or alphanumeric. For example:
The following outline is provided as an overview of and topical guide to cryptography:
There are various implementations of the Advanced Encryption Standard, also known as Rijndael.
The xor–encrypt–xor (XEX) is a (tweakable) mode of operation of a block cipher. In tweaked-codebook mode with ciphertext stealing, it is one of the more popular modes of operation for whole-disk encryption. XEX is also a common form of key whitening, and part of some smart card proposals.