Update for cryptography 0.8 and general cleanups

6 files changed, 12 insertions, 74 deletions

diff --git a/README b/README
index 7e848aca..36d7055f 100644
--- a/README
+++ b/README
@@ -36,7 +36,7 @@ Requirements
 
   - Python 2.6 or better <http://www.python.org/> - this includes Python
     3.2 and higher as well.
-  - Cryptography 0.7 or better <https://cryptography.io>
+  - Cryptography 0.8 or better <https://cryptography.io>
   - pyasn1 0.1.7 or better <https://pypi.python.org/pypi/pyasn1>
 
 If you have setuptools, you can build and install paramiko and all its
diff --git a/paramiko/dsskey.py b/paramiko/dsskey.py
index 2c90694f..8e0c2ba9 100644
--- a/paramiko/dsskey.py
+++ b/paramiko/dsskey.py
@@ -118,8 +118,8 @@ class DSSKey(PKey):
         m = Message()
         m.add_string('ssh-dss')
         # apparently, in rare cases, r or s may be shorter than 20 bytes!
-        rstr = util.deflate_long(int(r), 0)
-        sstr = util.deflate_long(int(s), 0)
+        rstr = util.deflate_long(r, 0)
+        sstr = util.deflate_long(s, 0)
         if len(rstr) < 20:
             rstr = zero_byte * (20 - len(rstr)) + rstr
         if len(sstr) < 20:
diff --git a/paramiko/ecdsakey.py b/paramiko/ecdsakey.py
index bc76b639..2f5c2c31 100644
--- a/paramiko/ecdsakey.py
+++ b/paramiko/ecdsakey.py
@@ -32,9 +32,6 @@ from cryptography.hazmat.primitives.asymmetric.utils import (
     decode_rfc6979_signature, encode_rfc6979_signature
 )
 
-from pyasn1.codec.der import encoder
-from pyasn1.type import namedtype, namedval, tag, univ
-
 from paramiko.common import four_byte, one_byte, zero_byte
 from paramiko.message import Message
 from paramiko.pkey import PKey
@@ -43,40 +40,6 @@ from paramiko.ssh_exception import SSHException
 from paramiko.util import deflate_long, inflate_long
 
 
-# RFC 5480, section 2.1.1
-class _ECParameters(univ.Choice):
-    # TODO: There are a few more options for this choice I think, the RFC says
-    # not to use them though...
-    componentType = namedtype.NamedTypes(
-        namedtype.NamedType("namedCurve", univ.ObjectIdentifier()),
-    )
-
-
-# RFC 5915, Appendix A
-class _ECPrivateKey(univ.Sequence):
-    componentType = namedtype.NamedTypes(
-        namedtype.NamedType(
-            "version",
-            univ.Integer(
-                namedValues=namedval.NamedValues(
-                    ("ecPrivkeyVer1", 1),
-                )
-            ),
-        ),
-        namedtype.NamedType("privateKey", univ.OctetString()),
-        namedtype.OptionalNamedType("parameters", _ECParameters().subtype(
-            implicitTag=tag.Tag(tag.tagClassContext, tag.tagFormatSimple, 0),
-        )),
-        namedtype.OptionalNamedType("publicKey", univ.BitString().subtype(
-            implicitTag=tag.Tag(tag.tagClassContext, tag.tagFormatSimple, 1),
-        )),
-    )
-
-
-_CURVE_TO_OID = {
-    ec.SECP256R1: univ.ObjectIdentifier("1.2.840.10045.3.1.7")
-}
-
 class ECDSAKey(PKey):
     """
     Representation of an ECDSA key which can be used to sign and verify SSH2
@@ -216,40 +179,17 @@ class ECDSAKey(PKey):
                         byte_chr(5) * 5, byte_chr(6) * 6, byte_chr(7) * 7]
 
     def _decode_key(self, data):
-        s = """
------BEGIN EC PRIVATE KEY-----
-%s
------END EC PRIVATE KEY-----
-""" % "\n".join(textwrap.wrap(base64.b64encode(data).decode(), 64))
-        key = serialization.load_pem_private_key(s.encode(), password=None, backend=default_backend())
+        key = serialization.load_der_private_key(data, password=None, backend=default_backend())
         self.signing_key = key
         self.verifying_key = key.public_key()
         self.size = key.curve.key_size
 
     def _to_der(self, key):
-        private_numbers = key.private_numbers()
-        public_numbers = private_numbers.public_numbers
-
-        private_key = deflate_long(
-            private_numbers.private_value, add_sign_padding=False
+        return key.private_bytes(
+            serialization.Encoding.DER,
+            serialization.Format.TraditionalOpenSSL,
+            serialization.NoEncryption(),
         )
-        x_str = deflate_long(public_numbers.x, add_sign_padding=False)
-        y_str = deflate_long(public_numbers.y, add_sign_padding=False)
-
-        key_length = key.curve.key_size // 8
-        if len(x_str) < key_length:
-            x_str = zero_byte * (key_length - len(x_str)) + x_str
-        if len(y_str) < key_length:
-            y_str = zero_byte * (key_length - len(y_str)) + y_str
-        public_key = b"\x04" + x_str + y_str
-
-        asn1_key = _ECPrivateKey()
-        asn1_key.setComponentByName("version", 1)
-        asn1_key.setComponentByName("privateKey", private_key)
-        asn1_key.setComponentByName("parameters")
-        asn1_key.getComponentByName("parameters").setComponentByName("namedCurve", _CURVE_TO_OID[type(key.curve)])
-        asn1_key.setComponentByName("publicKey", "'%s'H" % binascii.hexlify(public_key).decode())
-        return encoder.encode(asn1_key)
 
     def _sigencode(self, r, s):
         msg = Message()
diff --git a/setup.py b/setup.py
index e10a6390..a4977c15 100644
--- a/setup.py
+++ b/setup.py
@@ -41,7 +41,7 @@ try:
     from setuptools import setup
     kw = {
         'install_requires': [
-            'cryptography >= 0.7',
+            'cryptography >= 0.8',
             'pyasn1 >= 0.1.7',
         ],
     }
diff --git a/sites/www/installing.rst b/sites/www/installing.rst
index dc20590e..57b639f0 100644
--- a/sites/www/installing.rst
+++ b/sites/www/installing.rst
@@ -20,10 +20,8 @@ We currently support **Python 2.6, 2.7, 3.3+, and PyPy** (Python **3.2** should
 also work but has a less-strong compatibility guarantee from us.) Users on
 Python 2.5 or older are urged to upgrade.
 
-Paramiko has three hard dependencies: the pure-Python ECDSA module ``ecdsa``
-and ASN1 module ``pyasn1``, and the Cryptography library. ``ecdsa`` is easily
-installable from wherever you obtained Paramiko's package; Cryptography may
-require more work. Read on for details.
+Paramiko has two hard dependencies: the pure-Python ASN1 module ``pyasn1``, and
+the Cryptography library. Read on for details on installing ``cryptography``.
 
 If you need GSS-API / SSPI support, see :ref:`the below subsection on it
 <gssapi>` for details on additional dependencies.
diff --git a/tox-requirements.txt b/tox-requirements.txt
index 23ed06d8..47ddd792 100644
--- a/tox-requirements.txt
+++ b/tox-requirements.txt
@@ -1,3 +1,3 @@
 # Not sure why tox can't just read setup.py?
-cryptography >= 0.7
+cryptography >= 0.8
 pyasn1 >= 0.1.7