Simple Elliptic Curve Cryptography for Python compatible with the excellent SECCURE command line utility (version 0.5). It's licensed under LGPLv3. See LICENSE.

Do not use ``py-seccure`` when its operation can be timed by an attacker. See timing attack.

To get the public key from the private, you can use the original commandline utility:

$ seccure-key
Assuming curve p160.
Enter private key: my private key
The public key is: 8W;>i^H0qi|J&$coR5MFpR*Vn

In Python:

>>> import seccure
>>> str(seccure.passphrase_to_pubkey(b'my private key'))
'8W;>i^H0qi|J&$coR5MFpR*Vn'

To encrypt for a public key, one would use the original commandline utility as follows.

$ seccure-encrypt -o private.msg '8W;>i^H0qi|J&$coR5MFpR*Vn'
Assuming MAC length of 80 bits.
Go ahead and type your message ...
This is a very very secret message!
^D

In Python:

>>> ciphertext = seccure.encrypt(b'This is a very secret message\n', b'8W;>i^H0qi|J&$coR5MFpR*Vn')
>>> ciphertext
'\x00\x146\x17\xe9\xc1\x1a\x7fkX\xec\xa0n,h\xb4\xd0\x98\xeaO[\xf8\xfa\x85\xaa\xb37!\xf0j\x0e\xd4\xd0\x8b\xfe}\x8a\xd2+\xf2\xceu\x07\x90K2E\x12\x1d\xf1\xd8\x8f\xc6\x91\t<w\x99\x1b9\x98'

There is a shorthand to encrypt a file:

>>> seccure.encrypt_file('/path/to/file',  '/path/to/file.enc', '8W;>i^H0qi|J&$coR5MFpR*Vn')

To decrypt the message with the original utility:

$ seccure-decrypt -i private.msg
Assuming MAC length of 80 bits.
Assuming curve p160.
Enter private key: my private key
This is a very very secret message!
Integrity check successful, message unforged!

In Python:

>>> seccure.decrypt(ciphertext, b'my private key')
'This is a very secret message\n'

And to decrypt a file:

>>> seccure.decrypt_file('/path/to/file.enc',  '/path/to/file', b'my private key')

To create a signature:

$ seccure-sign
Assuming curve p160.
Enter private key: my private key
Go ahead and type your message ...
This message will be signed
^D
Signature: $HPI?t(I*1vAYsl$|%21WXND=6Br*[>k(OR9B!GOwHqL0s+3Uq

In Python:

>>> seccure.sign(b'This message will be signed\n', b'my private key')
'$HPI?t(I*1vAYsl$|%21WXND=6Br*[>k(OR9B!GOwHqL0s+3Uq'

To verify a signature:

$ seccure-verify '8W;>i^H0qi|J&$coR5MFpR*Vn' '$HPI?t(I*1vAYsl$|%21WXND=6Br*[>k(OR9B!GOwHqL0s+3Uq'
Go ahead and type your message ...
This message will be signed
^D
Signature successfully verified!

In Python:

>>> seccure.verify(b'This message will be signed\n', b'$HPI?t(I*1vAYsl$|%21WXND=6Br*[>k(OR9B!GOwHqL0s+3Uq', b'8W;>i^H0qi|J&$coR5MFpR*Vn')
True

$ apt-get install libgmp3-dev build-essential python-dev python-pip libmpfr-dev libmpc-dev
$ pip install seccure

$ apt-get install libgmp-dev build-essential python-dev python-pip libmpfr-dev libmpc-dev
$ pip install seccure

$ port install py27-gmpy2
$ pip install seccure

To help out, you could:

1. Test and report any bugs or other difficulties.
2. Implement missing features, such as seccure-dh, seccure-veridec and seccure-signcrypt.
3. Package py-seccure (or the original SECCURE itself) for your platform.
4. Write more unit tests.