sick let the user sign and check files in a simple and secure way. It uses the
well-known ed25519 algorithm and simple asymetric keys
format as a backend, using the library from
The process is simple. Bob generates two keys: a private and a public one:
Bob must then give his public key to Alice, preferably in person, to ensure the public key she has is Bob's (yes, crypto involves paranoia). Bob can now sign a file, and mail it to Alice with the following command:
$ sick -v -g bob Creating private key bob.key Creating public key bob.pub
Alice can now safely retrieve her lolcat picture using her
$ sick -v -s -f bob.key lolcat.png | mail email@example.com Signing stream (1337 bytes)
Alice can now be SURE that the cat she's looking at is the one sent by Bob! If it wasn't,$ sick -v -f bob.pub lolcat.png.signed > lolcat.png Extracting signature from input Verifying stream (1337 bytes) Stream check OK
lolcat.pngwould simply be an empty file.
git clone git://z3bra.org/sick.git
safe is built using
mk is also supported):
$ make # make install
If you find any bug, please report them, or send a patch to
dev AT z3bra DOT org.