Free pgp encryption software for linux

Come And Go Encryption provides an encryption program based off one-time pads.
Cum And Go Encryption is a very basic program to encrypt or decrypt a program using a variant of the one-time pad. This allows for almost uncrackable encryption.
Why is it still crackable? The program uses one relatively small key to XOR the contents of another file, encrypting it.
A one-time pad uses a very large key (about the same size as the file/data to encrypt) and is completely random. Still, the encryption is good enough to mask the identity of a program or document, or stop someone from accessing that document or program.
The origins of this program were an effort to stop a specific kind of movie and image from being viewed normally.
Installing is a breeze: simply run the program. Put it anywhere you like, it wont matter as long as you put the full path to the program to encrypt/decrypt.
Run the program to see a basic description of its use.
This program works very well in windows but was designed for use in Linux/UNIX. The stdout option allows for decryption to standard output, allowing one to pipe the programs decrypted data to another program.
This could be used to view an encrypted movie without having to write the whole movie to disk; the only problem with this is that on some Operating Systems pipes are slow and inefficient, especially with a high-bitrate movie. Steps will be taken to speed this up in the future.
Enhancements:
- Fix password use so the password is not shown in "encrypted" files
- Use an actual encryption method, and not a cheesy XOR
- Adapt CAG to use modules such as SHA, Crypt, MD5, and others

Fire Encrypter is an Firefox extension which gives you encryption/decryption and hashing functionality right from your Firefox browser, mostly useful for developers or for education & fun.
The new FireEncrypter is ready! (v-3.0, this version contains the following ciphers:
- AES (Rijndael 128Bit)
- Affine
- Caesar
- XOR
- OTP (One Time Pad)
- Vigenere
- Rail Fence
- Morse Encoder
- MD2 Hashing
- MD5 Hashing
- SHA1 Hashing
- SHA256 Hashing
- SHA384 Hashing
- SHA512 Hashing
- Secure password generator.

Cryptonit project is a client side cryptographic tool which allows you to encrypt/decrypt and sign/verify files with PKI (Public Key Infrastructure) certificates.
Main features:
- Encryption/decryption based on highly reliable algorithms
- Signature/verification procedures ensuring tamper-proof documents
- Use of passwords, certificates & smart (chip) cards for file encryption
- Address book for saving and organizing contacts
- Ability to import contacts and their certificates from the corporate directory (LDAP import)
- Multiple user account management
- Interfaces in both English and French
- CRL download
- RSA cryptography (public key cryptography standard)

Eureka Encryption Global Edition contains file encryption, multiple encryption, merge encryption, multiple file encryption, embedded applications (Crypt Words, Steganographer, Interface) and other tools such as a file shredder and scrambler.

Eureka Encryption Global Edition is available for Windows, Mac and Linux. Other applications are available from the website.

Crypt is a small C program that utilizes the crypt(3) function to include DES password checking/encryption in shell scripts.

Usage:

./crypt < salt > < string >

Crypt::OpenPGP is a Pure-Perl OpenPGP implementation.

SYNOPSIS

my $pgp = Crypt::OpenPGP->new;
my $result = $pgp->handle( Data => $message_body );

my $signature = $pgp->sign(
Filename => $file,
KeyID => $key_id,
Passphrase => $pass,
Detach => 1,
Armour => 1,
);

my $valid = $pgp->verify(
Signature => $signature,
Files => [ $file ],
);

my $ciphertext = $pgp->encrypt(
Filename => $file,
Recipients => $key_id,
Armour => 1,
);

my $plaintext = $pgp->decrypt(
Data => $ciphertext,
Passphrase => $pass,
);

Crypt::OpenPGP is a pure-Perl implementation of the OpenPGP standard[1]. In addition to support for the standard itself, Crypt::OpenPGP claims compatibility with many other PGP implementations, both those that support the standard and those that preceded it.

Crypt::OpenPGP provides signing/verification, encryption/decryption, keyring management, and key-pair generation; in short it should provide you with everything you need to PGP-enable yourself. Alternatively it can be used as part of a larger system; for example, perhaps you have a web-form-to-email generator written in Perl, and youd like to encrypt outgoing messages, because they contain sensitive information. Crypt::OpenPGP can be plugged into such a scenario, given your public key, and told to encrypt all messages; they will then be readable only by you.

This module currently supports RSA and DSA for digital signatures, and RSA and ElGamal for encryption/decryption. It supports the symmetric ciphers 3DES, Blowfish, IDEA, Twofish, CAST5, and Rijndael (AES). Rijndael is supported for key sizes of 128, 192, and 256 bits. Crypt::OpenPGP supports the digest algorithms MD5, SHA-1, and RIPE-MD/160. And it supports ZIP and Zlib compression.

upgpverify verifies a PGP signed or encrypted and signed message on stdin, checks the user id or key id against a database, if wanted, and starts another program, providing the payload of the PGP message on an own file descriptor.
upgpverify is designed to work under qmail. It can handle MIME and non-MIME (traditional PGP format) messages. It handles base64 and quoted-printable.
upgpverify also sets a few environment variables containing various header of the incoming email.
Supported PGP / GPG versions:
- GPG 1.0.4 (earlier version are possibly okay, too, but have not been tested).
- PGP 2.6.x (tested with 2.6.3is)
- PGP 5.0i (tested with some 5.0i1b version)
Enhancements:
- added a --max-len option to restrict the size of the incoming messages

PHP Screw is a PHP script encryption tool. When you are developing a commercial package using PHP, the script can be distributed as encrypted up until just before execution, preserving your intellectual property.