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objc_util and CommonCrypto
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I am trying to use
objc_util
to use someCommonCrypto
methods but I can't seem to figure out how to load the CommonCrypto framework.My goal is to decrypt something using native
AES
. And also to use the nativepbkdf2
implementation.Most python implementations of
AES
use compiledc
code. I haven't found a "pure python" version that works on Pythonista.Is this possible using the
objc_util
module? -
I dint think you need to load it. just reference the functions
i.e
from obj_util import * CCCryptorCreate = c.CCCryptorCreate CCCryptorCreate.argtypes = [.......] CCCryptorCreate.restype = ......
you might want to check out Cethrics work converting opengles, i think he used a method to use c like prototypes to autogenerate the ctypes wrappers.
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Does that mean I would have to write c like code to use this framework?
I found a library that wraps CommonCrypto to encrypt/decrypt using AES written in objc- I wanted to port it over to Pythonista...
https://github.com/rnapier/ios5ptl/blob/master/ch11/CryptPic/CryptPic/RNCryptManager.m
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AES is available out of the box, see example usage below. Though I would be interested to compare to native CommonCrypto as a benchmark...
import base64 import hashlib from Crypto import Random from Crypto.Cipher import AES class AESCipher(object): def __init__(self, key): self.bs = 32 self.key = hashlib.sha256(key.encode()).digest() def encrypt(self, raw): raw = self._pad(raw) iv = Random.new().read(AES.block_size) cipher = AES.new(self.key, AES.MODE_CBC, iv) return base64.b64encode(iv + cipher.encrypt(raw)) def decrypt(self, enc): enc = base64.b64decode(enc) iv = enc[:AES.block_size] cipher = AES.new(self.key, AES.MODE_CBC, iv) return self._unpad(cipher.decrypt(enc[AES.block_size:])).decode('utf-8') def _pad(self, s): return s + (self.bs - len(s) % self.bs) * chr(self.bs - len(s) % self.bs) @staticmethod def _unpad(s): return s[:-ord(s[len(s)-1:])] if __name__ == '__main__': # pragma: no cover aes = AESCipher('this is my key') plaintext = 'hello, I am very happy to meet you!' print 'plain =', plaintext ciphertext = aes.encrypt(plaintext) print 'cipher =', ciphertext plaintwo = aes.decrypt(ciphertext) print 'plain2 =', plaintwo
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@jadeblaquiere said:
AES is available out of the box, see example usage below.
Thanks you so much! I had no idea the
Crypto
module was included - I didn't see any documentation for it.... (though I probably should've checkedsite-packages
)