Tinfoil Hat Linux (THL) is a compact security-focused

Linux distribution A Linux distribution, often abbreviated as distro, is an operating system that includes the Linux kernel for its kernel functionality. Although the name does not imply product distribution per se, a distro—if distributed on its own—is oft ...

designed for high

security Security is protection from, or resilience against, potential harm (or other unwanted coercion). Beneficiaries (technically referents) of security may be persons and social groups, objects and institutions, ecosystems, or any other entity or ...

developed by ''The Shmoo Group''. The first version (1.000) was released in February 2002. By 2013, it had become a low-priority project. Its image files and source are available in

gzip gzip is a file format and a software application used for file compression and decompression. The program was created by Jean-loup Gailly and Mark Adler as a free software replacement for the compress program used in early Unix systems, and ...

format. THL can be used on modern PCs using an

Intel 80386 The Intel 386, originally released as the 80386 and later renamed i386, is the third-generation x86 architecture microprocessor from Intel. It was the first 32-bit computing, 32-bit processor in the line, making it a significant evolution in ...

or better, with at least 8 MB of

RAM Ram, ram, or RAM most commonly refers to: * A male sheep * Random-access memory, computer memory * Ram Trucks, US, since 2009 ** List of vehicles named Dodge Ram, trucks and vans ** Ram Pickup, produced by Ram Trucks Ram, ram, or RAM may also ref ...

. The distribution fits on a single HD

floppy disk A floppy disk or floppy diskette (casually referred to as a floppy, a diskette, or a disk) is a type of disk storage composed of a thin and flexible disk of a magnetic storage medium in a square or nearly square plastic enclosure lined with a ...

. The small footprint provides additional benefits beyond making the system easy to understand and verify. A

hard drive A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating hard disk drive platter, pla ...

is not required to use THL, making it easier to "sanitize" the computer after use. The logo of Tinfoil Hat is Tux, the

Linux Linux ( ) is a family of open source Unix-like operating systems based on the Linux kernel, an kernel (operating system), operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically package manager, pac ...

mascot, wearing a tinfoil hat. ''The Shmoo Group'' website says "It started as a secure, single floppy, bootable

distribution for storing PGP keys and then encrypting, signing, and wiping files. At some point, it became an exercise in over-engineering."

Security features

Tinfoil Hat uses a number of measures to defeat hardware and software surveillance methods like

keystroke logging Keystroke logging, often referred to as keylogging or keyboard capturing, is the action of recording (logging) the keys struck on a keyboard, typically covertly, so that a person using the keyboard is unaware that their actions are being monitore ...

video camera A video camera is an optical instrument that captures videos, as opposed to a movie camera, which records images on film. Video cameras were initially developed for the television industry but have since become widely used for a variety of other ...

, and TEMPEST: *Encryption —

GNU Privacy Guard GNU Privacy Guard (GnuPG or GPG) is a free-software replacement for Symantec's cryptographic software suite PGP. The software is compliant with the now obsoleted , the IETF standards-track specification of OpenPGP. Modern versions of PGP are ...

(GPG)

public key cryptography Public-key cryptography, or asymmetric cryptography, is the field of cryptographic systems that use pairs of related keys. Each key pair consists of a public key and a corresponding private key. Key pairs are generated with cryptographic al ...

software is included in THL. *Data retrieval — All temporary files are created on an encrypted

RAM disk A RAM drive (also called a RAM disk) is a block of random-access memory ( primary storage or volatile memory) that a computer's software is treating as if the memory were a disk drive (secondary storage). RAM drives provide high-performance te ...

that is destroyed on shutdown. Even the GPG key file information can be stored encrypted on the floppy. *Keystroke monitoring — THL has GPG Grid, a wrapper for GPG that lets you use a video game-style character entry system instead of typing in your

passphrase A passphrase is a sequence of words or other text used to control access to a computer system, program or data. It is similar to a password in usage, but a passphrase is generally longer for added security. Passphrases are often used to control ...

. Keystroke loggers get a set of grid points, instead of a passphrase. *Power usage and other

side-channel attack In computer security, a side-channel attack is a type of security exploit that leverages information inadvertently leaked by a system—such as timing, power consumption, or electromagnetic or acoustic emissions—to gain unauthorized access to ...

s — Under the Paranoid options, a copy of GPG runs in the background generating keys and encrypting random documents. This makes it harder to determine when real encryption is taking place. * Reading the screen over the user's shoulder is made difficult when Tinfoil Hat is switched to paranoid mode, which sets the screen to a very low contrast.

Applications

THL can be used on most modern PCs using the

x86 x86 (also known as 80x86 or the 8086 family) is a family of complex instruction set computer (CISC) instruction set architectures initially developed by Intel, based on the 8086 microprocessor and its 8-bit-external-bus variant, the 8088. Th ...

processor architecture. For example, one might install it on a computer that is kept in a locked room, not connected to any network, and used only for cryptographically signing keys. It is fairly easy to create the Tinfoil Hat

booting In computing, booting is the process of starting a computer as initiated via Computer hardware, hardware such as a physical button on the computer or by a software command. After it is switched on, a computer's central processing unit (CPU) h ...

floppy with

Microsoft Windows Windows is a Product lining, product line of Proprietary software, proprietary graphical user interface, graphical operating systems developed and marketed by Microsoft. It is grouped into families and subfamilies that cater to particular sec ...

. Verifying the

checksum A checksum is a small-sized block of data derived from another block of digital data for the purpose of detecting errors that may have been introduced during its transmission or storage. By themselves, checksums are often used to verify dat ...

can pose a greater challenge. The text of the documentation is salted with a few jokes, the humor working in stark contrast to the serious and paranoiac tone of the surrounding text. The very name of the distribution pokes fun at itself, as Tinfoil Hats are commonly ascribed to paranoiacs as a method of protecting oneself from mind-control waves. Tinfoil Hat Linux requires one to work in a text-only environment in

, electing to start users with a

Bourne shell The Bourne shell (sh) is a shell command-line interpreter for computer operating systems. It first appeared on Version 7 Unix, as its default shell. Unix-like systems continue to have /bin/sh—which will be the Bourne shell, or a symbolic lin ...

, the text editor vi, and with no

graphical user interface A graphical user interface, or GUI, is a form of user interface that allows user (computing), users to human–computer interaction, interact with electronic devices through Graphics, graphical icon (computing), icons and visual indicators such ...

. It uses

BusyBox BusyBox is a software suite that provides several List of Unix commands, Unix utilities in a single executable file. It runs in a variety of POSIX environments such as Linux, Android (operating system), Android, and FreeBSD, although many of the ...

instead of the normal Util-Linux, the

GNU Core Utilities The GNU Core Utilities or coreutils is a collection of GNU software that implements many standard, Unix-based shell commands. The utilities generally provide POSIX compliant interface when the environment variable is set, but otherwise offers ...

(formerly known as FileUtils, ShellUtils, and TextUtils), and other common

Unix Unix (, ; trademarked as UNIX) is a family of multitasking, multi-user computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, a ...

tools. Tinfoil Hat also offers the

GNU nano GNU nano is a text editor for Unix-like computing systems or operating environments using a command line interface. It emulates the Pico text editor, part of the Pine email client, and also provides additional functionality. Unlike Pico, nano i ...

text editor.

References

* * * *

External links

Official website

Evilmutant.com article about Tinfoil Hat Linux, with screenshots

Another evilmutant.com article giving links to other media which picked up the previous article
{{Linux-distro Cryptographic software Floppy-based Linux distributions Floppy disk-based operating systems RPM-based Linux distributions Linux distributions

Security features

Applications

See also

References

External links