MyCrptool

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A python package that include commonly used cryptographic algorithm and tools.

Install

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pip install mycrptool

Dependencies

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Here are external libraries that is used in this package.

bitarray

Usage

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This package consists of 4 parts: symmetric, asymetric, hash, and tools.
To import all modules, it is recommanded to run from mycryptool import *

symmetric

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This module includes 2 symmetric algorithms: AES128 and DES.

AES128

The Default scheme is CBC. if you want to try other schemes, welcome to explore the AES class (in symmetric.aes128).

Encrypt:

data = b'Jessie Pinkman in the house'
key = 'key'
cipher = symmetric.aes128.encrypt(key, data)

Decrypt:

symmetric.aes128.decrypt(key, cipher)

DES

DES only supports 2 schemes: CBC and ECB. Supported Features: encrypt and decrypt.

Encrypt:

key = b'chopperc'
iv = b'66666666'
data = b'Yo Yo Yo, Jessie Pinkman in the house!!!'

cipher = symmetric.des.des_cbc(data, iv, key, True)  # CBC

cipher = symmetric.des.des_ecb(data, key, True)  # ECB

Decrypt:

deciphered = symmetric.des.des_cbc(cipher, iv, key, False)  # CBC
deciphered = symmetric.des.des_ecb(cipher, key, False)  # ECB

asymmetric

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This module includes 2 asymmetric algorithms: RSA and Elliptic Curve.
Supported Features: encrypt, decrypt, generate signature, and validate signature.

RSA

Encrypt:

data = b'Jessie Pinkman in the house'
# Warning: it takes a while to generate key pairs ( large prime numbers).
pub, pri = asymmetric.rsa.generate_key_pair()
cipher = asymmetric.rsa.encrypt(data, pub)

Decrypt:

asymmetric.rsa.decrypt(cipher, pri)

Generate signature:

signature = asymmetric.rsa.get_signature(hash.md5.md5(data), pri)
print(signature)

Validate signature:

asymmetric.rsa.is_valid_signature(hash.md5.md5(data), signature, pub)

Elliptic Curve

As for now, this module only supports 1 curve: ecp256k1.
However, you can Implement your own curve derived from the EllipticCurve class.

Implement customize curve:

class ecp256k1(EllipticCurve):
	# ecp256k1 https://www.secg.org/sec2-v2.pdf
	def __init__(self):
		a = 0
		b = 7
		p = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC2F
		Gx = 0x79BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798
		Gy = 0x483ADA7726A3C4655DA4FBFC0E1108A8FD17B448A68554199C47D08FFB10D4B8
		n = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141

		super(ecp256k1, self).__init__(a, b, p, (Gx, Gy), n)

Encrypt:

ec = asymmetric.elliptic_curve.ecp256k1()
pri = ec.get_private_key()
pub = ec.get_public_key(pri)
ec_cipher = ec.encrypt(data, pub)
print(ec_cipher)

Decrypt:

ec.decrypt(ec_cipher, pri)

Generate signature:

signature = ec.get_signature(hash.sha1.sha1(data), pri)

Validate signature:

ec.is_valid_signature(hash.sha1.sha1(data), signature, pub)