Drop asn1crypto and just support pyasn1

I added asn1crypto support three years ago in #33, because I was under
the impression that other Python packages such as PyCA cryptography
were going to standardize on asn1crypto. Since 2017 cryptography and
other dependencies have dropped asn1crypto. kdcproxy is currently the
only package in RHEL that depends on python-asn1crypto.

Let's keep it simple and just support pyasn1.

Signed-off-by: Christian Heimes <[email protected]>

Author: tiran

kdcproxy/codec.py

@@ -19,36 +19,11 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 # THE SOFTWARE.
 
-import os
 import struct
 
+from kdcproxy import parse_pyasn1 as asn1mod
 from kdcproxy.exceptions import ParsingError
 
-ASN1MOD = os.environ.get('KDCPROXY_ASN1MOD')
-
-if ASN1MOD is None:
-    try:
-        from asn1crypto.version import __version_info__ as asn1crypto_version
-    except ImportError:
-        asn1crypto_version = None
-    else:
-        if asn1crypto_version >= (0, 22, 0):
-            ASN1MOD = 'asn1crypto'
-    if ASN1MOD is None:
-        try:
-            __import__('pyasn1')
-        except ImportError:
-            pass
-        else:
-            ASN1MOD = 'pyasn1'
-
-if ASN1MOD == 'asn1crypto':
-    from kdcproxy import parse_asn1crypto as asn1mod
-elif ASN1MOD == 'pyasn1':
-    from kdcproxy import parse_pyasn1 as asn1mod
-else:
-    raise ValueError("Invalid KDCPROXY_ASN1MOD='{}'".format(ASN1MOD))
-
 
 class ProxyRequest(object):
     TYPE = None

kdcproxy/parse_asn1crypto.py

@@ -24,7 +24,7 @@
 from setuptools import setup
 
 install_requires = [
-    'asn1crypto>=0.23',
+    'pyasn1',
     'dnspython'
 ]
 

setup.py

@@ -20,7 +20,6 @@
 # THE SOFTWARE.
 
 import os
-import sys
 import unittest
 from base64 import b64decode
 try:
@@ -226,21 +225,6 @@ def test_kpasswdreq(self):
             'FREEIPA.LOCAL KPASSWD-REQ (603 bytes) (version 0x0001)'
         )
 
-    def test_asn1mod(self):
-        modmap = {
-            'asn1crypto': (
-                'kdcproxy.parse_asn1crypto', 'kdcproxy.parse_pyasn1'),
-            'pyasn1': (
-                'kdcproxy.parse_pyasn1', 'kdcproxy.parse_asn1crypto'),
-        }
-        asn1mod = os.environ.get('KDCPROXY_ASN1MOD', None)
-        if asn1mod is None:
-            self.fail("Tests require KDCPROXY_ASN1MOD env var.")
-        self.assertIn(asn1mod, modmap)
-        mod, opposite = modmap[asn1mod]
-        self.assertIn(mod, set(sys.modules))
-        self.assertNotIn(opposite, set(sys.modules))
-
 
 class KDCProxyConfigTests(unittest.TestCase):
 

tests.py

@@ -1,16 +1,11 @@
 [tox]
 minversion = 2.3.1
-envlist = {py36,py37,py38,py39}-{asn1crypto,pyasn1},pep8,py3pep8,doc,coverage-report
+envlist = py36,py37,py38,py39,pep8,py3pep8,doc,coverage-report
 skip_missing_interpreters = true
 
 [testenv]
 deps =
     .[tests]
-    pyasn1: pyasn1
-    asn1crypto: asn1crypto>=0.23
-setenv =
-    asn1crypto: KDCPROXY_ASN1MOD=asn1crypto
-    pyasn1: KDCPROXY_ASN1MOD=pyasn1
 commands =
     {envpython} -m coverage run --parallel \
         -m pytest --capture=no --strict {posargs}