Encrypting Your Files
Many people today require encryption of their personal files for various reasons. Hopefully this node will show you some methods for encrypting and obfuscating your data to prevent theft, interception and spying.
Starting with a program that turns normal files into password-protected ones is the first step. Many programs from Microsoft Word to ZIP's portable format use inadequate protection. Advertising high-level encryption does not make a program secure.
- PGP is one of the most popular encryption programs - mainly due to it's ease of integration with Windows mail clients. Both a freeware version is available, though not for commercial use, and an open source clone: GPG.
- AxCrypt - open-source GPL program on SourceForge -- compression and double-click Edit/View for secure document storage on Windows 95/98/ME/NT/2K/XP, locally or remote using AES.
- Mcrypt - A very simple command-line program with a wide variety of algorithms and the source code is available. Can be ported to Windows with Cygwin. Intended to be a replacement of the old UNIX "crypt" which used DES, under the GPL.
- FlexiCrypt - A java program with a wide variety of algorithms provided by a reliable Java Security Provider (FlexiProvider) and the source code is available. Allows one to use symmetric, asymmetric and hybrid encryption on files. Also provides secure file deletion.
- Ashampoo Privacy Protector commercial program creates self-extracting encrypted files. CD burning capabilities. Available in English and German.
- WinRAR - commercial Windows compression program - the latest versions use high-strength AES encryption.
- iOpus SEA tool - Windows freeware that uses high-strength blowfish encryption to make self-extracting files.
- Secrets Keeper - 256-bit AES encryption for Windows Explorer and Microsoft Office including Microsoft Word, Excel and PowerPoint documents.
- Attach Plus - Windows shareware - Attach Plus allows you to modify, PDF or ZIP, 128-bit encrypt, and attach your files while you are ataching (or printing) to an existing OR new email message. Supports Outlook, Outlook Express, Goldmine, ACT, Groupwise and Eudora.
- PKWARE - SecureZIP - AES-256 encryption with either pass phrases or digital certificates to protect files on hard drive, laptop, CD's or removable storage as well as to protect email attachments.
- See: Hard Disk Encryption
More security measures
- Recognize that your operating system probably leaves plain text copies of your encrypted data all over the place, but especially in temporary files.
- Note that, facing a well resourced attacker, it is very difficult to safely and securely delete data. (See http://www.cs.auckland.ac.nz/~pgut001/pubs/secure_del.html)
- Use of a steganographic file system (see http://www.mcdonald.org.uk/StegFS/)
- For the ultra-paranoid, maybe mention something about TEMPEST here (see http://www.eskimo.com/~joelm/tempest.html and http://cryptome.org/nsa-tempest.htm. (Though jya.com seems to be down at the moment, so some papers are currently inaccessible.))