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exaexa / codecrypt

Post-quantum cryptography tool (THIS REPOSITORY IS ONLY A MIRROR OF THE MAIN ONE, PLEASE DO NOT FILE BUGS HERE)
https://gitea.blesmrt.net/exa/codecrypt
GNU Lesser General Public License v3.0
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Secret key protection #22

Closed ghost closed 7 years ago

ghost commented 7 years ago

Mirek, Which symmetric key algorithm ( AES , XSalsa20 ... ) is used to protect the private key generated in Codecrypt , if at all ?

exaexa commented 7 years ago

No possibility at the moment. I didn't have time to implement that feature yet.

Patches/pull requests welcome 😉

vstoykovbg commented 7 years ago

This is critical feature.

What is the point of using post-quantum cryptography if the private key is not protected? The user would like to encrypt the private key and store it on "cloud" services (because what is the point to keep off-site backup of your data if you don't keep off-site backup of your key).

Also there should be a CPU and memory intensive key stretching when protecting the key with a passphrase.

Which key stretching functions are quantum computer proof?

I am using scrypt with additional sha512: sha512(key+salt+digest_from_heavy_scrypt_cycles).

Here is the proof of concept code: https://github.com/vstoykovbg/slowkdf

Is this key stretching function useful against quantum computers?

exaexa commented 7 years ago

@vstoykovbg any suggestions on parameters for scrypt?

exaexa commented 7 years ago

...also, is there some good alternative for getpass(3) which is now marked obsolete?

exaexa commented 7 years ago

Work in progress in 578691f45efed9c15bcb6e93001dc01858b56d44 (keyring-passwords branch), @vstoykovbg @deltaspectre could you test it after I finish it for privkeys? (It currently works on symmetric keys, but the rest of the expansion is more or less trivial)

exaexa commented 7 years ago

Completed in 104ee129511d1164d05a06ac5d5ca39edbb20d4c , scheduled for merging to 1.8

I'll close this issue and go through some testing. If you find issues, please report them (as separate bugs).