First, define which ciphers and in which order you want to use. For more information about ciphers avaliable, type:
gpg --versionand jump to the section "ciphers" or "symmetric":
Symetryczne: IDEA, 3DES, CAST5, BLOWFISH, AES, AES192, AES256, TWOFISH, CAMELLIA128, CAMELLIA192, CAMELLIA256
Enter them in the config section of our "encrypt-multiple.sh" script:
So now if you want to encrypt message in file.txt, just run:
After entering passphases (twice) you will get the encrypted file "file.txt.n" where n is a number of used ciphers (n will be necesary while during decryption).
For decrypting above message we just need to enter valid password. We don't need the names and order of used ciphers as gpg detects it automagically. The n - number of passes (used ciphers) is "encoded" in file extension.
(3) Output file sizes.
Output file sizes inceases as more ciphers are used. Here is an example of file sizes (uncompressed and compressed with bzip2). Cipher used are:
TWOFISH AES256 CAMELLIA256 BLOWFISH CAST5 TWOFISH AES256 CAMELLIA256 BLOWFISH CAST5.
More reading about ciphers and symmetric encryption: GPG Encryption Guide - Part 4 (Symmetric Encryption).
If you want to try decoding, here is 5-fold encrypted text (n=5). The password is chemoinformatics.