TrueCrypt
TrueCrypt is a free open-source on-the-fly encryption (OTFE) program for Microsoft Windows XP/2000/2003 (Linux version is planned). It allows one to create a virtual encrypted disk within a file, and then mount it as a real disk. The virtual disk is entirely encrypted (i.e., including file names and folder names) and behaves as a real physical disk drive. TrueCrypt can also encrypt an entire hard disk partition or a storage device/medium, such as floppy disk or USB memory stick. The encryption algorithms used by TrueCrypt are AES, Blowfish, CAST5, Serpent, Triple DES, and Twofish. It also allows to use a cascade of ciphers, e.g., AES-Twofish-Serpent.
One of the remarkable features of TrueCrypt is that it provides two levels of plausible deniability, which might be useful in case an adversary forces the user to reveal the password:
1) Hidden volume (more information may be found here).
2) No TrueCrypt volume can be identified (TrueCrypt volumes cannot be distinguished from random data).
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History of TrueCrypt
TrueCrypt is based upon Encryption for the Masses (also called E4M). E4M was a popular open-source OTFE program first released in 1997. However in 2000, it was discontinued as the author, Paul Le Roux, began working on commercial OTFE software with SecurStar. The first version of TrueCrypt was released on February 2, 2004. At that time, it was the only open-source OTFE software that fully supported Windows XP and the only open-source OTFE software for Windows XP that provided plausible deniability.
Shortly after its release, SecurStar claimed that E4M was their property and the author, Paul Le Roux, while an employee, had stolen its source code, presumably from a simlar product, DriveCrypt, and released it under an unauthorized license. It was seen as a measure to stop TrueCrypt competing with their commercial product, DriveCrypt.
The SecurStar claims were believed to be baseless, since when E4M was released, neither SecurStar nor DriveCrypt existed. SecurStar hired the authors of Scramdisk and E4M in 2001. These developers also signed a contract that obliged to terminate the development of Scramdisk and E4M. The Scramdisk and E4M websites started redirecting their visitors to SecurStar's website, while stating that DriveCrypt (a closed-source commercial product) would supersede E4M and that Scramdisk would become obsolete.
According to some sources, there was a legal dispute between Paul Le Roux and his former employer, SecurStar. Because of legal reasons, Paul Le Roux refused to confirm whether the claims were true. Subsequently, development of TrueCrypt was officially suspended and its website, truecrypt.org, shut down. From that point onwards, TrueCrypt could only be obtained through third party sites and the program's legality was often questioned.
TrueCrypt 1.0 supported Windows 98/ME and Windows 2000/XP. A later revision 1.0a removed the Windows 98/ME support, because the author of the Windows 9x driver for E4M claimed he gave no permission that would allow his code to be used in projects derived from E4M. Remark: The authors of Scramdisk and E4M swapped their code (the author of Scramdisk provided the driver for Windows 9x, and the author of E4M provided the driver for Windows NT, which allowed the shareware Scramdisk NT to be created and released afterwards).
On June 7, 2004, TrueCrypt 2.0 was released, presumably from a different group/authors due to the different signing signature of TrueCrypt Foundation. Previous versions were signed by TrueCrypt Team. It was released under the GPL, which caused controversy as it included works of previous authors who have not authorized the license change. A few weeks later, TrueCrypt 2.1 was released, by the same people. The license reverted back to the E4M license.
Up till 2.1, TrueCrypt had to be obtained from dubious sources. There was no official website. The only proof of origin was the digital signature. On October 1, 2004, TrueCrypt 2.1a was released on SourceForge and truecrypt.sourceforge.net became the official TrueCrypt website. At that point it was believed that TrueCrypt finally gained legitimacy.
Other encryption programs
On the fly
- CrossCrypt
- FreeOTFE
Regular
External links
Categories: Cryptographic software