Designed for encrypting and decrypting short messages using latest cryptographic primitives while still generating nice human readable inputs and outputs. These should make it easier to pass the key and cipher information by hand or over the phone.

Fair warning - this has been written as learning exercise and is not recommend for any real use at this stage. Feedback welcome.

The following example generates a new key, encrypts and then decrypts a short message.

./sigli genkey -o /tmp/demokey1
echo "a short message to encode at 1234" > plain_text1
./sigli encrypt /tmp/demokey1 -i plain_text1 -o cipher_text
./sigli decrypt /tmp/demokey1 -i cipher_text -o plain_text2
cat plain_text2

By default sigli use hexadecimal encoding for keys and a blocked uppercase encoding for cipher text. So in the above example /tmp/demokey1 might contain:

16C1-F0AF-5B92-64CC-8A09-04F2-641E-BE64-4A41-6028-E92D-49D6-81EE-9D6A-F5AC-4E7A

and the cipher-text file might contain:

ZPPCR PXPNL QPYAG QSDIL EAQCB MXTDD
ZLJDJ BCRJZ QNDRX XMPPV OHWQX GUBBO
OVYMI BRXIE JXJPS ITCOH NEULZ E

These values will vary for each run because key is random and the cipher also contains a random element. The output appears much longer than the input because the default algorithm (AES-256-GCM) adds a fixed overhead of four of bytes of authentication data and twelve bytes of random nonce data.

A different algorithm can be selected using the --algo (or -a) parameter.

./sigli  -a aes128gcm genkey -o /tmp/demokey1
echo "a short message to encode at 1234" > plain_text1
./sigli -a aes128gcm encrypt /tmp/demokey1 -i plain_text1 -o cipher_text
./sigli -a aes128gcm decrypt /tmp/demokey1 -i cipher_text -o plain_text2
cat plain_text2

This works the same as the previous example only with a shorter key, for example:

10AA-E181-8D00-113C-2A32-BF5B-A01F-017A

If the --input (-i) argument is omitted the encrypt and decrypt commands read from the standard input. If the --output (-o) argument is omitted the encrypt and decrypt commands write to the standard output.

./sigli genkey -o /tmp/demokey1
echo "a short message to encode at 1234" | ./sigli encrypt /tmp/demokey1 > cipher_text
cat cipher_text | ./sigli decrypt /tmp/demokey1 

By default sigli assumes that the input will be in plain text format and the output will be in signal format. However if you want to recrypt a message to need to change the input and output format accordingly. The input format is controlled by the --input-format (-I) argument and the output format is controlled by the --output-format (-O) argument.

./sigli genkey -o /tmp/demokey1
./sigli genkey -o /tmp/demokey2
echo "a short message to encode at 1234" | ./sigli encrypt /tmp/demokey1  | ./sigli encrypt -I signal1 /tmp/demokey2 > cipher_text
cat cipher_text | ./sigli decrypt -O signal1 /tmp/demokey2 | ./sigli decrypt /tmp/demokey1 

The available formats are raw, hex, plain1 and signal1. The default key format is hex, the default plain text format is plain1 and the default cipher text format is signal1.