gotr: provide potr (rev f5551d6). now only depends on PyCrypto>=2.1

gotr/potr/compatcrypto/common.py

@@ -0,0 +1,104 @@
+#    Copyright 2012 Kjell Braden <afflux@pentabarf.de>
+#
+#    This file is part of the python-potr library.
+#
+#    python-potr is free software; you can redistribute it and/or modify
+#    it under the terms of the GNU Lesser General Public License as published by
+#    the Free Software Foundation; either version 3 of the License, or
+#    (at your option) any later version.
+#
+#    python-potr is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    GNU Lesser General Public License for more details.
+#
+#    You should have received a copy of the GNU Lesser General Public License
+#    along with this library.  If not, see <http://www.gnu.org/licenses/>.
+
+# some python3 compatibilty
+from __future__ import unicode_literals
+
+import logging
+import struct
+
+from potr.utils import human_hash, bytes_to_long, unpack, pack_mpi
+
+DEFAULT_KEYTYPE = 0x0000
+pkTypes = {}
+def registerkeytype(cls):
+    if not hasattr(cls, 'parsePayload'):
+        raise TypeError('registered key types need parsePayload()')
+    pkTypes[cls.keyType] = cls
+    return cls
+
+def generateDefaultKey():
+    return pkTypes[DEFAULT_KEYTYPE].generate()
+
+class PK(object):
+    __slots__ = []
+
+    @classmethod
+    def generate(cls):
+        raise NotImplementedError
+
+    def sign(self, data):
+        raise NotImplementedError
+    def verify(self, data):
+        raise NotImplementedError
+    def fingerprint(self):
+        raise NotImplementedError
+
+    def serializePublicKey(self):
+        return struct.pack(b'!H', self.keyType) \
+                + self.getSerializedPublicPayload()
+
+    def getSerializedPublicPayload(self):
+        buf = b''
+        for x in self.getPublicPayload():
+            buf += pack_mpi(x)
+        return buf
+
+    def getPublicPayload(self):
+        raise NotImplementedError
+
+    def serializePrivateKey(self):
+        return struct.pack(b'!H', self.keyType) \
+                + self.getSerializedPrivatePayload()
+
+    def getSerializedPrivatePayload(self):
+        buf = b''
+        for x in self.getPrivatePayload():
+            buf += pack_mpi(x)
+        return buf
+
+    def getPrivatePayload(self):
+        raise NotImplementedError
+
+    def cfingerprint(self):
+        return '{0:040x}'.format(bytes_to_long(self.fingerprint()))
+
+    @classmethod
+    def parsePrivateKey(cls, data):
+        implCls, data = cls.getImplementation(data)
+        logging.debug('Got privkey of type %r' % implCls)
+        return implCls.parsePayload(data, private=True)
+
+    @classmethod
+    def parsePublicKey(cls, data):
+        implCls, data = cls.getImplementation(data)
+        logging.debug('Got pubkey of type %r' % implCls)
+        return implCls.parsePayload(data)
+
+    def __str__(self):
+        return human_hash(self.cfingerprint())
+    def __repr__(self):
+        return '<{cls}(fpr=\'{fpr}\')>'.format(
+                cls=self.__class__.__name__, fpr=str(self))
+
+    @staticmethod
+    def getImplementation(data):
+        typeid, data = unpack(b'!H', data)
+        cls = pkTypes.get(typeid, None)
+        if cls is None:
+            raise NotImplementedError('unknown typeid %r' % typeid)
+        return cls, data