Cryptography and Steganography
Utility which encodes and decodes binary files into
five-letter code groups just like
secret agents use. Handy for sending small binary messages by
telephone, radio, or telegraph.
Quantum mechanics teaches us that, at the deepest level, uncertainty
rules the universe: there are things we cannot predict, even in
principle. HotBits harnesses this fundamental
uncertainty of nature to generate truly random bits, unlike the
pseudorandom sequences created by an algorithm on a computer.
Along the way, you'll find a discussion of the hardware and
software used to generate the random bytes comprehensive enough
to build your own, and peek under the hood
of quantum mechanics to see why the data are genuinely random,
and some of the implications of all this.
A collection of Web pages and programs in the JavaScript
language perform military-grade encryption (256 bit secret key
AES)
entirely within your Web browser—you needn't
download nor install any software, and nothing is sent to
any Web site when you encrypt or decrypt a message. You
can download the page source and JavaScript programs to your
own computer and use them even when not connected
to the Internet. Companion pages provide a
text-based steganography facility and key generator
suitable for preparing one-time key lists. Please
visit the
JavaScrypt Home Page
for details, or the
JavaScrypt Tutorial
for an overview of the available facilities.
Command-line utility which computes and checks
message digests (digital signatures) generated by the MD5
algorithm as defined by RFC 1321. This program is handy for software
installation, file verification, and other system administration shell
scripts and Perl programs. Includes complete C source code for Unix
and a ready to run Win32 executable.
New version 2.0 adds multiple file signature
generation (including wildcard expansion in the
Win32 version), tagging signatures with
file names, and optional lower case letters in
hexadecimal output.
Airline pilots, military personnel, cops, amateur radio operators, and
others who need to accurately transmit sequences of letters
and numbers across voice communication links with limited
fidelity mostly rely on a phonetic alphabet developed in the
1950's by NATO. This document provides both a
Web-based reference
to the phonetic alphabet and a version you can download
and install on your
Palm OS handheld
computer.
Utilities for generating
one-time key or password pads in a
variety of formats. Options allow you to select key length, whether
digits or letters are used, and whether alphabetic keys are truly
random or obey the digraph statistics of English text (less secure, but
easier to remember and transcribe). Both a
C language
program and a Web page with an embedded
generator program in JavaScript are available.
A program for the analysis (not generation) of random and
pseudorandom sequences. A variety of tests, including many from
Knuth, are applied to the contents of a file and the results reported
on standard output. In portable C; public domain. October 1998
update adds frequency histogram display, optional analysis of input as
a bitstream, CSV output for postprocessing by other programs, and
improved HTML documentation.
Steganosaurus is a plain text steganography (secret writing)
utility which encodes a (usually encrypted) binary file as gibberish
text, based on either a spelling dictionary or words taken from a text
document. In portable C; public domain.
It seems like wherever you go on the Internet, there's
somebody—governments, big tech companies, Internet service
providers, and a multitude of nefarious or just annoying
actors—trying to snoop on your activity. Here are some
tools, accessible to people without extensive technical
experience, which allow you to reclaim some of your privacy
and protect your communications from eavesdroppers.