Obtain codesigning information with pyobjc

codesign.py

import objc
from Foundation import NSBundle, NSURL
Security = NSBundle.bundleWithIdentifier_('com.apple.security')

class StaticCodeError(Exception):
    pass

class SigningInfoError(Exception):
    pass

kSecCSDefaultFlags           = 0
kSecCSSigningInformation     = 1 << 1
kSecCSRequirementInformation = 1 << 2
kSecCSCalculateCMSDigest     = 1 << 6

_f = [
      ('SecStaticCodeCreateWithPath',   'i@Io^@'),
      ('SecCodeCopySigningInformation', 'i@Io^@'),
     ]

objc.loadBundleFunctions(Security, globals(), _f)

def codesign_info(path):
    url = NSURL.fileURLWithPath_(path)
    err, codeobj  = SecStaticCodeCreateWithPath(url, kSecCSDefaultFlags, None)
    if err != 0:
        raise StaticCodeError('unable to create SecCodeRef with provided path')
    flags = kSecCSSigningInformation | kSecCSRequirementInformation | kSecCSCalculateCMSDigest
    err, codeinfo = SecCodeCopySigningInformation(codeobj, flags, None)
    if err != 0:
        raise SigningInfoError('unable to retrieve signing information for SecCodeRef')
    return codeinfo