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Currently trying to decrypt cipher text from WolfSSL implementation. Your implementation is having trouble decrypting despite both you and WolfSSL using the Nippon encrypt and decrypt source code for Camellia.

import camellia 
key = b'SzE6pcNdUGbF0nVTNjqDj79v8JwBf7P2'
iv = b'\xd7\xfe3\x1d\x10\x85&^\xe6\x12p\xf8GZ\xb2\xa4'
salt = 'b\xc41\xa6\x8d\xa1b\x00'
cipher_text = b'\xb5\x7f\xbdpkkF\xef1\xbfX\xaf\x94\xf0\xec|V\xe4\xa8\xbe\x1a0B\xa8\x04Aq\x84\xd4\xa6M\xf8\x13\x9e<=\xbd\x1cbD\xdd\x82\xbe\\\x94\xf4m('

new_key = hashlib.pbkdf2_hmac('sha256', key, salt, 4096)

c2 = camellia.CamelliaCipher(key=key, IV=bytes(iv), mode=camellia.MODE_CBC)

print("decrypt >>>> ", c2.decrypt(encrypted).decode() )

This should decrypt to "Hello there, you decrypted the string"

Check code for PEP-8

• camellia (1957f21)
  • __init__.py (1957f21)
• camellia_build
  • __init__.py
  • _build_utils.py (cbda033)
• setup.py (d7f890a)

Sources:

• PEP-8: https://www.python.org/dev/peps/pep-0008/

Make code PEP 272 compliant (API for Block Encryption Algorithms v1.0).

Current status:

• new method as an alternative constructor (with 053455c)
• ECB mode of operation
• CBC mode of operation
• CFB mode of operation (with d26b370)
• OFB mode of operation (with d26b370)
• CTR mode of operation
• Different attributes of the CamelliaCipher class (with 227ef7e)
  • block_size
  • IV
• key_size variable (with 4e69c1e)
• block_size variable (with 4e69c1e)

Sources:

• PEP-272: https://www.python.org/dev/peps/pep-0272/

The code checks for the camellia dll of your current architecture. However, it gets the architecture of the system, not the architecture of the currently running Python. When using 32 bit Python it tries to open camellia-win32-AMD64-WindowsPE.dll, which fails.

Check code for PEP-257 (Docstring Conventions).

• Done (e9022f6).

Sources:

• PEP-257: https://www.python.org/dev/peps/pep-0257/

https://github.com/Varbin/python-camellia/blob/master/src/camellia/__init__.py#L192-L199

It appears self.counter is called twice (not once) for each block - once to check the length, another to actually decrypt. Should the second instance be ctr instead of self.counter()?

Hi,
When I use CBC mode, it works but when I use CTR as follows:
camellia.CamelliaCipher(key=b'16 byte long key', IV=b'16 byte iv. abcd', mode=camellia.MODE_CTR)

I get the following error:
NotImplementedError: This mode is not supported!

Could you help me with this, please!

Possible solutions are:

• C-Extension (platform independent way, not that good on PyPy, )
• CFFI (good on PyPy, also on CPython)
• Cython (CPython only!, slow on PyPy)
• SWIG (Difficult to install and compile, probably bad user experience, especially on systems without integrated package managers)

=> All solutions will drop IronPython and Jython support. Proper .NET or Java libraries should be used in Jython/IronPython.

Currently, python-camellia uses the official reference implementation. This is not optimized in any way. The official statement (by the camellia authors) is:

This reference code is written for an easy understanding of the Camellia
encryption algorithm and a tool for validity verification of a source code that you made.
It is not intended to be used for a specific application.
No optimized techniques are adopted at all in this code.

In future versions,

Crypto engine for Camellia (C [mini], BSD License)

will be used.

Current Status:

• Unix-like
• Windows (only recompile needed!)

Sources:

• Camellia Crypto Engines: https://info.isl.ntt.co.jp/crypt/eng/camellia/engine.html
• Camellia Reference Code: https://info.isl.ntt.co.jp/crypt/eng/camellia/dl/camellia.c.gz