1343 lines
47 KiB
Python
1343 lines
47 KiB
Python
# ===================================================================
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#
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# Copyright (c) 2015, Legrandin <helderijs@gmail.com>
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# All rights reserved.
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#
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# Redistribution and use in source and binary forms, with or without
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# modification, are permitted provided that the following conditions
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# are met:
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#
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# 1. Redistributions of source code must retain the above copyright
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# notice, this list of conditions and the following disclaimer.
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# 2. Redistributions in binary form must reproduce the above copyright
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# notice, this list of conditions and the following disclaimer in
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# the documentation and/or other materials provided with the
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# distribution.
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#
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# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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# COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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# POSSIBILITY OF SUCH DAMAGE.
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# ===================================================================
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from __future__ import print_function
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import re
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import struct
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import binascii
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from Crypto.Util.py3compat import bord, tobytes, tostr, bchr, is_string
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from Crypto.Math.Numbers import Integer
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from Crypto.Util.asn1 import (DerObjectId, DerOctetString, DerSequence,
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DerBitString)
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from Crypto.PublicKey import (_expand_subject_public_key_info,
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_create_subject_public_key_info,
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_extract_subject_public_key_info)
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from Crypto.Hash import SHA512, SHAKE256
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from Crypto.Random import get_random_bytes
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from ._point import EccPoint, EccXPoint, _curves
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from ._point import CurveID as _CurveID
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class UnsupportedEccFeature(ValueError):
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pass
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class EccKey(object):
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r"""Class defining an ECC key.
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Do not instantiate directly.
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Use :func:`generate`, :func:`construct` or :func:`import_key` instead.
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:ivar curve: The **canonical** name of the curve as defined in the `ECC table`_.
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:vartype curve: string
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:ivar pointQ: an ECC point representating the public component.
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:vartype pointQ: :class:`EccPoint` or :class:`EccXPoint`
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:ivar d: A scalar that represents the private component
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in NIST P curves. It is smaller than the
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order of the generator point.
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:vartype d: integer
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:ivar seed: A seed that representats the private component
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in Ed22519 (32 bytes), Curve25519 (32 bytes),
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Curve448 (56 bytes), Ed448 (57 bytes).
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:vartype seed: bytes
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"""
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def __init__(self, **kwargs):
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"""Create a new ECC key
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Keywords:
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curve : string
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The name of the curve.
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d : integer
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Mandatory for a private key one NIST P curves.
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It must be in the range ``[1..order-1]``.
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seed : bytes
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Mandatory for a private key on Ed25519 (32 bytes),
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Curve25519 (32 bytes), Curve448 (56 bytes) or Ed448 (57 bytes).
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point : EccPoint or EccXPoint
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Mandatory for a public key. If provided for a private key,
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the implementation will NOT check whether it matches ``d``.
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Only one parameter among ``d``, ``seed`` or ``point`` may be used.
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"""
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kwargs_ = dict(kwargs)
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curve_name = kwargs_.pop("curve", None)
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self._d = kwargs_.pop("d", None)
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self._seed = kwargs_.pop("seed", None)
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self._point = kwargs_.pop("point", None)
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if curve_name is None and self._point:
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curve_name = self._point.curve
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if kwargs_:
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raise TypeError("Unknown parameters: " + str(kwargs_))
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if curve_name not in _curves:
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raise ValueError("Unsupported curve (%s)" % curve_name)
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self._curve = _curves[curve_name]
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self.curve = self._curve.canonical
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count = int(self._d is not None) + int(self._seed is not None)
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if count == 0:
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if self._point is None:
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raise ValueError("At lest one between parameters 'point', 'd' or 'seed' must be specified")
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return
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if count == 2:
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raise ValueError("Parameters d and seed are mutually exclusive")
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# NIST P curves work with d, EdDSA works with seed
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# RFC 8032, 5.1.5
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if self._curve.id == _CurveID.ED25519:
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if self._d is not None:
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raise ValueError("Parameter d can only be used with NIST P curves")
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if len(self._seed) != 32:
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raise ValueError("Parameter seed must be 32 bytes long for Ed25519")
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seed_hash = SHA512.new(self._seed).digest() # h
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self._prefix = seed_hash[32:]
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tmp = bytearray(seed_hash[:32])
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tmp[0] &= 0xF8
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tmp[31] = (tmp[31] & 0x7F) | 0x40
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self._d = Integer.from_bytes(tmp, byteorder='little')
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# RFC 8032, 5.2.5
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elif self._curve.id == _CurveID.ED448:
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if self._d is not None:
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raise ValueError("Parameter d can only be used with NIST P curves")
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if len(self._seed) != 57:
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raise ValueError("Parameter seed must be 57 bytes long for Ed448")
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seed_hash = SHAKE256.new(self._seed).read(114) # h
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self._prefix = seed_hash[57:]
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tmp = bytearray(seed_hash[:57])
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tmp[0] &= 0xFC
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tmp[55] |= 0x80
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tmp[56] = 0
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self._d = Integer.from_bytes(tmp, byteorder='little')
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# RFC 7748, 5
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elif self._curve.id == _CurveID.CURVE25519:
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if self._d is not None:
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raise ValueError("Parameter d can only be used with NIST P curves")
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if len(self._seed) != 32:
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raise ValueError("Parameter seed must be 32 bytes long for Curve25519")
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tmp = bytearray(self._seed)
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tmp[0] &= 0xF8
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tmp[31] = (tmp[31] & 0x7F) | 0x40
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self._d = Integer.from_bytes(tmp, byteorder='little')
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elif self._curve.id == _CurveID.CURVE448:
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if self._d is not None:
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raise ValueError("Parameter d can only be used with NIST P curves")
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if len(self._seed) != 56:
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raise ValueError("Parameter seed must be 56 bytes long for Curve448")
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tmp = bytearray(self._seed)
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tmp[0] &= 0xFC
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tmp[55] |= 0x80
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self._d = Integer.from_bytes(tmp, byteorder='little')
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else:
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if self._seed is not None:
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raise ValueError("Parameter 'seed' cannot be used with NIST P-curves")
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self._d = Integer(self._d)
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if not 1 <= self._d < self._curve.order:
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raise ValueError("Parameter d must be an integer smaller than the curve order")
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def __eq__(self, other):
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if not isinstance(other, EccKey):
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return False
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if other.has_private() != self.has_private():
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return False
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return other.pointQ == self.pointQ
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def __repr__(self):
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if self.has_private():
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if self._curve.is_edwards:
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extra = ", seed=%s" % tostr(binascii.hexlify(self._seed))
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else:
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extra = ", d=%d" % int(self._d)
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else:
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extra = ""
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if self._curve.id in (_CurveID.CURVE25519,
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_CurveID.CURVE448):
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x = self.pointQ.x
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result = "EccKey(curve='%s', point_x=%d%s)" % (self._curve.canonical, x, extra)
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else:
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x, y = self.pointQ.xy
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result = "EccKey(curve='%s', point_x=%d, point_y=%d%s)" % (self._curve.canonical, x, y, extra)
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return result
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def has_private(self):
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"""``True`` if this key can be used for making signatures or decrypting data."""
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return self._d is not None
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# ECDSA
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def _sign(self, z, k):
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assert 0 < k < self._curve.order
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order = self._curve.order
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blind = Integer.random_range(min_inclusive=1,
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max_exclusive=order)
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blind_d = self._d * blind
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inv_blind_k = (blind * k).inverse(order)
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r = (self._curve.G * k).x % order
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s = inv_blind_k * (blind * z + blind_d * r) % order
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return (r, s)
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# ECDSA
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def _verify(self, z, rs):
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order = self._curve.order
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sinv = rs[1].inverse(order)
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point1 = self._curve.G * ((sinv * z) % order)
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point2 = self.pointQ * ((sinv * rs[0]) % order)
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return (point1 + point2).x == rs[0]
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@property
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def d(self):
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if not self.has_private():
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raise ValueError("This is not a private ECC key")
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return self._d
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@property
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def seed(self):
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if not self.has_private():
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raise ValueError("This is not a private ECC key")
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return self._seed
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@property
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def pointQ(self):
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if self._point is None:
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self._point = self._curve.G * self._d
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return self._point
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def public_key(self):
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"""A matching ECC public key.
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Returns:
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a new :class:`EccKey` object
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"""
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return EccKey(curve=self._curve.canonical, point=self.pointQ)
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def _export_SEC1(self, compress):
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if not self._curve.is_weierstrass:
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raise ValueError("SEC1 format is only supported for NIST P curves")
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# See 2.2 in RFC5480 and 2.3.3 in SEC1
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#
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# The first byte is:
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# - 0x02: compressed, only X-coordinate, Y-coordinate is even
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# - 0x03: compressed, only X-coordinate, Y-coordinate is odd
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# - 0x04: uncompressed, X-coordinate is followed by Y-coordinate
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#
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# PAI is in theory encoded as 0x00.
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modulus_bytes = self.pointQ.size_in_bytes()
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if compress:
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if self.pointQ.y.is_odd():
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first_byte = b'\x03'
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else:
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first_byte = b'\x02'
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public_key = (first_byte +
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self.pointQ.x.to_bytes(modulus_bytes))
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else:
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public_key = (b'\x04' +
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self.pointQ.x.to_bytes(modulus_bytes) +
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self.pointQ.y.to_bytes(modulus_bytes))
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return public_key
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def _export_eddsa_public(self):
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x, y = self.pointQ.xy
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if self._curve.id == _CurveID.ED25519:
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result = bytearray(y.to_bytes(32, byteorder='little'))
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result[31] = ((x & 1) << 7) | result[31]
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elif self._curve.id == _CurveID.ED448:
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result = bytearray(y.to_bytes(57, byteorder='little'))
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result[56] = (x & 1) << 7
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else:
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raise ValueError("Not an EdDSA key to export")
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return bytes(result)
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def _export_montgomery_public(self):
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if not self._curve.is_montgomery:
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raise ValueError("Not a Montgomery key to export")
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x = self.pointQ.x
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field_size = self.pointQ.size_in_bytes()
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result = bytearray(x.to_bytes(field_size, byteorder='little'))
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return bytes(result)
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def _export_subjectPublicKeyInfo(self, compress):
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if self._curve.is_edwards:
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oid = self._curve.oid
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public_key = self._export_eddsa_public()
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params = None
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elif self._curve.is_montgomery:
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oid = self._curve.oid
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public_key = self._export_montgomery_public()
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params = None
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else:
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oid = "1.2.840.10045.2.1" # unrestricted
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public_key = self._export_SEC1(compress)
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params = DerObjectId(self._curve.oid)
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return _create_subject_public_key_info(oid,
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public_key,
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params)
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def _export_rfc5915_private_der(self, include_ec_params=True):
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assert self.has_private()
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# ECPrivateKey ::= SEQUENCE {
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# version INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1),
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# privateKey OCTET STRING,
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# parameters [0] ECParameters {{ NamedCurve }} OPTIONAL,
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# publicKey [1] BIT STRING OPTIONAL
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# }
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# Public key - uncompressed form
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modulus_bytes = self.pointQ.size_in_bytes()
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public_key = (b'\x04' +
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self.pointQ.x.to_bytes(modulus_bytes) +
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self.pointQ.y.to_bytes(modulus_bytes))
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seq = [1,
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DerOctetString(self.d.to_bytes(modulus_bytes)),
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DerObjectId(self._curve.oid, explicit=0),
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DerBitString(public_key, explicit=1)]
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if not include_ec_params:
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del seq[2]
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return DerSequence(seq).encode()
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def _export_pkcs8(self, **kwargs):
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from Crypto.IO import PKCS8
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if kwargs.get('passphrase', None) is not None and 'protection' not in kwargs:
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raise ValueError("At least the 'protection' parameter must be present")
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if self._seed is not None:
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oid = self._curve.oid
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private_key = DerOctetString(self._seed).encode()
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params = None
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else:
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oid = "1.2.840.10045.2.1" # unrestricted
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private_key = self._export_rfc5915_private_der(include_ec_params=False)
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params = DerObjectId(self._curve.oid)
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result = PKCS8.wrap(private_key,
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oid,
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key_params=params,
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**kwargs)
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return result
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def _export_public_pem(self, compress):
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from Crypto.IO import PEM
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encoded_der = self._export_subjectPublicKeyInfo(compress)
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return PEM.encode(encoded_der, "PUBLIC KEY")
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def _export_private_pem(self, passphrase, **kwargs):
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from Crypto.IO import PEM
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encoded_der = self._export_rfc5915_private_der()
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return PEM.encode(encoded_der, "EC PRIVATE KEY", passphrase, **kwargs)
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def _export_private_clear_pkcs8_in_clear_pem(self):
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from Crypto.IO import PEM
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encoded_der = self._export_pkcs8()
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return PEM.encode(encoded_der, "PRIVATE KEY")
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def _export_private_encrypted_pkcs8_in_clear_pem(self, passphrase, **kwargs):
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from Crypto.IO import PEM
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assert passphrase
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if 'protection' not in kwargs:
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raise ValueError("At least the 'protection' parameter should be present")
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encoded_der = self._export_pkcs8(passphrase=passphrase, **kwargs)
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return PEM.encode(encoded_der, "ENCRYPTED PRIVATE KEY")
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def _export_openssh(self, compress):
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if self.has_private():
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raise ValueError("Cannot export OpenSSH private keys")
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desc = self._curve.openssh
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if desc is None:
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raise ValueError("Cannot export %s keys as OpenSSH" % self.curve)
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elif desc == "ssh-ed25519":
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public_key = self._export_eddsa_public()
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comps = (tobytes(desc), tobytes(public_key))
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else:
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modulus_bytes = self.pointQ.size_in_bytes()
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if compress:
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first_byte = 2 + self.pointQ.y.is_odd()
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public_key = (bchr(first_byte) +
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self.pointQ.x.to_bytes(modulus_bytes))
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else:
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public_key = (b'\x04' +
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self.pointQ.x.to_bytes(modulus_bytes) +
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self.pointQ.y.to_bytes(modulus_bytes))
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middle = desc.split("-")[2]
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comps = (tobytes(desc), tobytes(middle), public_key)
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blob = b"".join([struct.pack(">I", len(x)) + x for x in comps])
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return desc + " " + tostr(binascii.b2a_base64(blob))
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def export_key(self, **kwargs):
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"""Export this ECC key.
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Args:
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format (string):
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The output format:
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- ``'DER'``. The key will be encoded in ASN.1 DER format (binary).
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For a public key, the ASN.1 ``subjectPublicKeyInfo`` structure
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defined in `RFC5480`_ will be used.
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For a private key, the ASN.1 ``ECPrivateKey`` structure defined
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in `RFC5915`_ is used instead (possibly within a PKCS#8 envelope,
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see the ``use_pkcs8`` flag below).
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- ``'PEM'``. The key will be encoded in a PEM_ envelope (ASCII).
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- ``'OpenSSH'``. The key will be encoded in the OpenSSH_ format
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(ASCII, public keys only).
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- ``'SEC1'``. The public key (i.e., the EC point) will be encoded
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into ``bytes`` according to Section 2.3.3 of `SEC1`_
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(which is a subset of the older X9.62 ITU standard).
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Only for NIST P-curves.
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- ``'raw'``. The public key will be encoded as ``bytes``,
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without any metadata.
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* For NIST P-curves: equivalent to ``'SEC1'``.
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* For Ed25519 and Ed448: ``bytes`` in the format
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defined in `RFC8032`_.
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* For Curve25519 and Curve448: ``bytes`` in the format
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defined in `RFC7748`_.
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passphrase (bytes or string):
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(*Private keys only*) The passphrase to protect the
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private key.
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use_pkcs8 (boolean):
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(*Private keys only*)
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If ``True`` (default and recommended), the `PKCS#8`_ representation
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will be used.
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It must be ``True`` for Ed25519, Ed448, Curve25519, and Curve448.
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If ``False`` and a passphrase is present, the obsolete PEM
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encryption will be used.
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protection (string):
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When a private key is exported with password-protection
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and PKCS#8 (both ``DER`` and ``PEM`` formats), this parameter MUST be
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present,
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For all possible protection schemes,
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refer to :ref:`the encryption parameters of PKCS#8<enc_params>`.
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It is recommended to use ``'PBKDF2WithHMAC-SHA512AndAES128-CBC'``.
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compress (boolean):
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If ``True``, the method returns a more compact representation
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of the public key, with the X-coordinate only.
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If ``False`` (default), the method returns the full public key.
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|
|
This parameter is ignored for Ed25519/Ed448/Curve25519/Curve448,
|
|
as compression is mandatory.
|
|
|
|
prot_params (dict):
|
|
When a private key is exported with password-protection
|
|
and PKCS#8 (both ``DER`` and ``PEM`` formats), this dictionary
|
|
contains the parameters to use to derive the encryption key
|
|
from the passphrase.
|
|
For all possible values,
|
|
refer to :ref:`the encryption parameters of PKCS#8<enc_params>`.
|
|
The recommendation is to use ``{'iteration_count':21000}`` for PBKDF2,
|
|
and ``{'iteration_count':131072}`` for scrypt.
|
|
|
|
.. warning::
|
|
If you don't provide a passphrase, the private key will be
|
|
exported in the clear!
|
|
|
|
.. note::
|
|
When exporting a private key with password-protection and `PKCS#8`_
|
|
(both ``DER`` and ``PEM`` formats), any extra parameters
|
|
to ``export_key()`` will be passed to :mod:`Crypto.IO.PKCS8`.
|
|
|
|
.. _PEM: http://www.ietf.org/rfc/rfc1421.txt
|
|
.. _`PEM encryption`: http://www.ietf.org/rfc/rfc1423.txt
|
|
.. _OpenSSH: http://www.openssh.com/txt/rfc5656.txt
|
|
.. _RFC5480: https://tools.ietf.org/html/rfc5480
|
|
.. _SEC1: https://www.secg.org/sec1-v2.pdf
|
|
.. _RFC7748: https://tools.ietf.org/html/rfc7748
|
|
|
|
Returns:
|
|
A multi-line string (for ``'PEM'`` and ``'OpenSSH'``) or
|
|
``bytes`` (for ``'DER'``, ``'SEC1'``, and ``'raw'``) with the encoded key.
|
|
"""
|
|
|
|
args = kwargs.copy()
|
|
ext_format = args.pop("format")
|
|
if ext_format not in ("PEM", "DER", "OpenSSH", "SEC1", "raw"):
|
|
raise ValueError("Unknown format '%s'" % ext_format)
|
|
|
|
compress = args.pop("compress", False)
|
|
|
|
if self.has_private():
|
|
passphrase = args.pop("passphrase", None)
|
|
if is_string(passphrase):
|
|
passphrase = tobytes(passphrase)
|
|
if not passphrase:
|
|
raise ValueError("Empty passphrase")
|
|
|
|
use_pkcs8 = args.pop("use_pkcs8", True)
|
|
if use_pkcs8 is False:
|
|
if self._curve.is_edwards:
|
|
raise ValueError("'pkcs8' must be True for EdDSA curves")
|
|
if self._curve.is_montgomery:
|
|
raise ValueError("'pkcs8' must be True for Curve25519")
|
|
if 'protection' in args:
|
|
raise ValueError("'protection' is only supported for PKCS#8")
|
|
|
|
if ext_format == "PEM":
|
|
if use_pkcs8:
|
|
if passphrase:
|
|
return self._export_private_encrypted_pkcs8_in_clear_pem(passphrase, **args)
|
|
else:
|
|
return self._export_private_clear_pkcs8_in_clear_pem()
|
|
else:
|
|
return self._export_private_pem(passphrase, **args)
|
|
elif ext_format == "DER":
|
|
# DER
|
|
if passphrase and not use_pkcs8:
|
|
raise ValueError("Private keys can only be encrpyted with DER using PKCS#8")
|
|
if use_pkcs8:
|
|
return self._export_pkcs8(passphrase=passphrase, **args)
|
|
else:
|
|
return self._export_rfc5915_private_der()
|
|
else:
|
|
raise ValueError("Private keys cannot be exported "
|
|
"in the '%s' format" % ext_format)
|
|
else: # Public key
|
|
if args:
|
|
raise ValueError("Unexpected parameters: '%s'" % args)
|
|
if ext_format == "PEM":
|
|
return self._export_public_pem(compress)
|
|
elif ext_format == "DER":
|
|
return self._export_subjectPublicKeyInfo(compress)
|
|
elif ext_format == "SEC1":
|
|
return self._export_SEC1(compress)
|
|
elif ext_format == "raw":
|
|
if self._curve.is_edwards:
|
|
return self._export_eddsa_public()
|
|
elif self._curve.is_montgomery:
|
|
return self._export_montgomery_public()
|
|
else:
|
|
return self._export_SEC1(compress)
|
|
else:
|
|
return self._export_openssh(compress)
|
|
|
|
|
|
def generate(**kwargs):
|
|
"""Generate a new private key on the given curve.
|
|
|
|
Args:
|
|
|
|
curve (string):
|
|
Mandatory. It must be a curve name defined in the `ECC table`_.
|
|
|
|
randfunc (callable):
|
|
Optional. The RNG to read randomness from.
|
|
If ``None``, :func:`Crypto.Random.get_random_bytes` is used.
|
|
"""
|
|
|
|
curve_name = kwargs.pop("curve")
|
|
curve = _curves[curve_name]
|
|
randfunc = kwargs.pop("randfunc", get_random_bytes)
|
|
if kwargs:
|
|
raise TypeError("Unknown parameters: " + str(kwargs))
|
|
|
|
if _curves[curve_name].id == _CurveID.ED25519:
|
|
seed = randfunc(32)
|
|
new_key = EccKey(curve=curve_name, seed=seed)
|
|
elif _curves[curve_name].id == _CurveID.ED448:
|
|
seed = randfunc(57)
|
|
new_key = EccKey(curve=curve_name, seed=seed)
|
|
elif _curves[curve_name].id == _CurveID.CURVE25519:
|
|
seed = randfunc(32)
|
|
new_key = EccKey(curve=curve_name, seed=seed)
|
|
_curves[curve_name].validate(new_key.pointQ)
|
|
elif _curves[curve_name].id == _CurveID.CURVE448:
|
|
seed = randfunc(56)
|
|
new_key = EccKey(curve=curve_name, seed=seed)
|
|
_curves[curve_name].validate(new_key.pointQ)
|
|
else:
|
|
d = Integer.random_range(min_inclusive=1,
|
|
max_exclusive=curve.order,
|
|
randfunc=randfunc)
|
|
new_key = EccKey(curve=curve_name, d=d)
|
|
|
|
return new_key
|
|
|
|
|
|
def construct(**kwargs):
|
|
"""Build a new ECC key (private or public) starting
|
|
from some base components.
|
|
|
|
In most cases, you will already have an existing key
|
|
which you can read in with :func:`import_key` instead
|
|
of this function.
|
|
|
|
Args:
|
|
curve (string):
|
|
Mandatory. The name of the elliptic curve, as defined in the `ECC table`_.
|
|
|
|
d (integer):
|
|
Mandatory for a private key and a NIST P-curve (e.g., P-256).
|
|
It must be an integer in the range ``[1..order-1]``.
|
|
|
|
seed (bytes):
|
|
Mandatory for a private key and curves Ed25519 (32 bytes),
|
|
Curve25519 (32 bytes), Curve448 (56 bytes) and Ed448 (57 bytes).
|
|
|
|
point_x (integer):
|
|
The X coordinate (affine) of the ECC point.
|
|
Mandatory for a public key.
|
|
|
|
point_y (integer):
|
|
The Y coordinate (affine) of the ECC point.
|
|
Mandatory for a public key,
|
|
except for Curve25519 and Curve448.
|
|
|
|
Returns:
|
|
:class:`EccKey` : a new ECC key object
|
|
"""
|
|
|
|
curve_name = kwargs["curve"]
|
|
curve = _curves[curve_name]
|
|
point_x = kwargs.pop("point_x", None)
|
|
point_y = kwargs.pop("point_y", None)
|
|
|
|
if "point" in kwargs:
|
|
raise TypeError("Unknown keyword: point")
|
|
|
|
if curve.id == _CurveID.CURVE25519:
|
|
|
|
if point_x is not None:
|
|
kwargs["point"] = EccXPoint(point_x, curve_name)
|
|
new_key = EccKey(**kwargs)
|
|
curve.validate(new_key.pointQ)
|
|
|
|
elif curve.id == _CurveID.CURVE448:
|
|
|
|
if point_x is not None:
|
|
kwargs["point"] = EccXPoint(point_x, curve_name)
|
|
new_key = EccKey(**kwargs)
|
|
curve.validate(new_key.pointQ)
|
|
|
|
else:
|
|
|
|
if None not in (point_x, point_y):
|
|
kwargs["point"] = EccPoint(point_x, point_y, curve_name)
|
|
new_key = EccKey(**kwargs)
|
|
|
|
# Validate that the private key matches the public one
|
|
# because EccKey will not do that automatically
|
|
if new_key.has_private() and 'point' in kwargs:
|
|
pub_key = curve.G * new_key.d
|
|
if pub_key.xy != (point_x, point_y):
|
|
raise ValueError("Private and public ECC keys do not match")
|
|
|
|
return new_key
|
|
|
|
|
|
def _import_public_der(ec_point, curve_oid=None, curve_name=None):
|
|
"""Convert an encoded EC point into an EccKey object
|
|
|
|
ec_point: byte string with the EC point (SEC1-encoded)
|
|
curve_oid: string with the name the curve
|
|
curve_name: string with the OID of the curve
|
|
|
|
Either curve_id or curve_name must be specified
|
|
|
|
"""
|
|
|
|
for _curve_name, curve in _curves.items():
|
|
if curve_oid and curve.oid == curve_oid:
|
|
break
|
|
if curve_name == _curve_name:
|
|
break
|
|
else:
|
|
if curve_oid:
|
|
raise UnsupportedEccFeature("Unsupported ECC curve (OID: %s)" % curve_oid)
|
|
else:
|
|
raise UnsupportedEccFeature("Unsupported ECC curve (%s)" % curve_name)
|
|
|
|
# See 2.2 in RFC5480 and 2.3.3 in SEC1
|
|
# The first byte is:
|
|
# - 0x02: compressed, only X-coordinate, Y-coordinate is even
|
|
# - 0x03: compressed, only X-coordinate, Y-coordinate is odd
|
|
# - 0x04: uncompressed, X-coordinate is followed by Y-coordinate
|
|
#
|
|
# PAI is in theory encoded as 0x00.
|
|
|
|
modulus_bytes = curve.p.size_in_bytes()
|
|
point_type = bord(ec_point[0])
|
|
|
|
# Uncompressed point
|
|
if point_type == 0x04:
|
|
if len(ec_point) != (1 + 2 * modulus_bytes):
|
|
raise ValueError("Incorrect EC point length")
|
|
x = Integer.from_bytes(ec_point[1:modulus_bytes+1])
|
|
y = Integer.from_bytes(ec_point[modulus_bytes+1:])
|
|
# Compressed point
|
|
elif point_type in (0x02, 0x03):
|
|
if len(ec_point) != (1 + modulus_bytes):
|
|
raise ValueError("Incorrect EC point length")
|
|
x = Integer.from_bytes(ec_point[1:])
|
|
# Right now, we only support Short Weierstrass curves
|
|
y = (x**3 - x*3 + curve.b).sqrt(curve.p)
|
|
if point_type == 0x02 and y.is_odd():
|
|
y = curve.p - y
|
|
if point_type == 0x03 and y.is_even():
|
|
y = curve.p - y
|
|
else:
|
|
raise ValueError("Incorrect EC point encoding")
|
|
|
|
return construct(curve=_curve_name, point_x=x, point_y=y)
|
|
|
|
|
|
def _import_subjectPublicKeyInfo(encoded, *kwargs):
|
|
"""Convert a subjectPublicKeyInfo into an EccKey object"""
|
|
|
|
# See RFC5480
|
|
|
|
# Parse the generic subjectPublicKeyInfo structure
|
|
oid, ec_point, params = _expand_subject_public_key_info(encoded)
|
|
|
|
nist_p_oids = (
|
|
"1.2.840.10045.2.1", # id-ecPublicKey (unrestricted)
|
|
"1.3.132.1.12", # id-ecDH
|
|
"1.3.132.1.13" # id-ecMQV
|
|
)
|
|
eddsa_oids = {
|
|
"1.3.101.112": ("Ed25519", _import_ed25519_public_key), # id-Ed25519
|
|
"1.3.101.113": ("Ed448", _import_ed448_public_key) # id-Ed448
|
|
}
|
|
xdh_oids = {
|
|
"1.3.101.110": ("Curve25519", _import_curve25519_public_key), # id-X25519
|
|
"1.3.101.111": ("Curve448", _import_curve448_public_key), # id-X448
|
|
}
|
|
|
|
if oid in nist_p_oids:
|
|
# See RFC5480
|
|
|
|
# Parameters are mandatory and encoded as ECParameters
|
|
# ECParameters ::= CHOICE {
|
|
# namedCurve OBJECT IDENTIFIER
|
|
# -- implicitCurve NULL
|
|
# -- specifiedCurve SpecifiedECDomain
|
|
# }
|
|
# implicitCurve and specifiedCurve are not supported (as per RFC)
|
|
if not params:
|
|
raise ValueError("Missing ECC parameters for ECC OID %s" % oid)
|
|
try:
|
|
curve_oid = DerObjectId().decode(params).value
|
|
except ValueError:
|
|
raise ValueError("Error decoding namedCurve")
|
|
|
|
# ECPoint ::= OCTET STRING
|
|
return _import_public_der(ec_point, curve_oid=curve_oid)
|
|
|
|
elif oid in eddsa_oids:
|
|
# See RFC8410
|
|
curve_name, import_eddsa_public_key = eddsa_oids[oid]
|
|
|
|
# Parameters must be absent
|
|
if params:
|
|
raise ValueError("Unexpected ECC parameters for ECC OID %s" % oid)
|
|
|
|
x, y = import_eddsa_public_key(ec_point)
|
|
return construct(point_x=x, point_y=y, curve=curve_name)
|
|
|
|
elif oid in xdh_oids:
|
|
curve_name, import_xdh_public_key = xdh_oids[oid]
|
|
|
|
# Parameters must be absent
|
|
if params:
|
|
raise ValueError("Unexpected ECC parameters for ECC OID %s" % oid)
|
|
|
|
x = import_xdh_public_key(ec_point)
|
|
return construct(point_x=x, curve=curve_name)
|
|
|
|
else:
|
|
raise UnsupportedEccFeature("Unsupported ECC OID: %s" % oid)
|
|
|
|
|
|
def _import_rfc5915_der(encoded, passphrase, curve_oid=None):
|
|
|
|
# See RFC5915 https://tools.ietf.org/html/rfc5915
|
|
#
|
|
# ECPrivateKey ::= SEQUENCE {
|
|
# version INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1),
|
|
# privateKey OCTET STRING,
|
|
# parameters [0] ECParameters {{ NamedCurve }} OPTIONAL,
|
|
# publicKey [1] BIT STRING OPTIONAL
|
|
# }
|
|
|
|
ec_private_key = DerSequence().decode(encoded, nr_elements=(2, 3, 4))
|
|
if ec_private_key[0] != 1:
|
|
raise ValueError("Incorrect ECC private key version")
|
|
|
|
scalar_bytes = DerOctetString().decode(ec_private_key[1]).payload
|
|
|
|
next_element = 2
|
|
|
|
# Try to decode 'parameters'
|
|
if next_element < len(ec_private_key):
|
|
try:
|
|
parameters = DerObjectId(explicit=0).decode(ec_private_key[next_element]).value
|
|
if curve_oid is not None and parameters != curve_oid:
|
|
raise ValueError("Curve mismatch")
|
|
curve_oid = parameters
|
|
next_element += 1
|
|
except ValueError:
|
|
pass
|
|
|
|
if curve_oid is None:
|
|
raise ValueError("No curve found")
|
|
|
|
for curve_name, curve in _curves.items():
|
|
if curve.oid == curve_oid:
|
|
break
|
|
else:
|
|
raise UnsupportedEccFeature("Unsupported ECC curve (OID: %s)" % curve_oid)
|
|
|
|
modulus_bytes = curve.p.size_in_bytes()
|
|
if len(scalar_bytes) != modulus_bytes:
|
|
raise ValueError("Private key is too small")
|
|
|
|
# Try to decode 'publicKey'
|
|
point_x = point_y = None
|
|
if next_element < len(ec_private_key):
|
|
try:
|
|
public_key_enc = DerBitString(explicit=1).decode(ec_private_key[next_element]).value
|
|
public_key = _import_public_der(public_key_enc, curve_oid=curve_oid)
|
|
point_x = public_key.pointQ.x
|
|
point_y = public_key.pointQ.y
|
|
next_element += 1
|
|
except ValueError:
|
|
pass
|
|
|
|
d = Integer.from_bytes(scalar_bytes)
|
|
return construct(curve=curve_name, d=d, point_x=point_x, point_y=point_y)
|
|
|
|
|
|
def _import_pkcs8(encoded, passphrase):
|
|
from Crypto.IO import PKCS8
|
|
|
|
algo_oid, private_key, params = PKCS8.unwrap(encoded, passphrase)
|
|
|
|
nist_p_oids = (
|
|
"1.2.840.10045.2.1", # id-ecPublicKey (unrestricted)
|
|
"1.3.132.1.12", # id-ecDH
|
|
"1.3.132.1.13" # id-ecMQV
|
|
)
|
|
eddsa_oids = {
|
|
"1.3.101.112": "Ed25519", # id-Ed25519
|
|
"1.3.101.113": "Ed448", # id-Ed448
|
|
}
|
|
xdh_oids = {
|
|
"1.3.101.110": "Curve25519", # id-X25519
|
|
"1.3.101.111": "Curve448", # id-X448
|
|
}
|
|
|
|
if algo_oid in nist_p_oids:
|
|
curve_oid = DerObjectId().decode(params).value
|
|
return _import_rfc5915_der(private_key, passphrase, curve_oid)
|
|
elif algo_oid in eddsa_oids:
|
|
if params is not None:
|
|
raise ValueError("EdDSA ECC private key must not have parameters")
|
|
curve_oid = None
|
|
seed = DerOctetString().decode(private_key).payload
|
|
return construct(curve=eddsa_oids[algo_oid], seed=seed)
|
|
elif algo_oid in xdh_oids:
|
|
curve_name = xdh_oids[algo_oid]
|
|
if params is not None:
|
|
raise ValueError("%s ECC private key must not have parameters" %
|
|
curve_name)
|
|
curve_oid = None
|
|
seed = DerOctetString().decode(private_key).payload
|
|
return construct(curve=xdh_oids[algo_oid], seed=seed)
|
|
else:
|
|
raise UnsupportedEccFeature("Unsupported ECC purpose (OID: %s)" % algo_oid)
|
|
|
|
|
|
def _import_x509_cert(encoded, *kwargs):
|
|
|
|
sp_info = _extract_subject_public_key_info(encoded)
|
|
return _import_subjectPublicKeyInfo(sp_info)
|
|
|
|
|
|
def _import_der(encoded, passphrase):
|
|
|
|
try:
|
|
return _import_subjectPublicKeyInfo(encoded, passphrase)
|
|
except UnsupportedEccFeature as err:
|
|
raise err
|
|
except (ValueError, TypeError, IndexError):
|
|
pass
|
|
|
|
try:
|
|
return _import_x509_cert(encoded, passphrase)
|
|
except UnsupportedEccFeature as err:
|
|
raise err
|
|
except (ValueError, TypeError, IndexError):
|
|
pass
|
|
|
|
try:
|
|
return _import_rfc5915_der(encoded, passphrase)
|
|
except UnsupportedEccFeature as err:
|
|
raise err
|
|
except (ValueError, TypeError, IndexError):
|
|
pass
|
|
|
|
try:
|
|
return _import_pkcs8(encoded, passphrase)
|
|
except UnsupportedEccFeature as err:
|
|
raise err
|
|
except (ValueError, TypeError, IndexError):
|
|
pass
|
|
|
|
raise ValueError("Not an ECC DER key")
|
|
|
|
|
|
def _import_openssh_public(encoded):
|
|
parts = encoded.split(b' ')
|
|
if len(parts) not in (2, 3):
|
|
raise ValueError("Not an openssh public key")
|
|
|
|
try:
|
|
keystring = binascii.a2b_base64(parts[1])
|
|
|
|
keyparts = []
|
|
while len(keystring) > 4:
|
|
lk = struct.unpack(">I", keystring[:4])[0]
|
|
keyparts.append(keystring[4:4 + lk])
|
|
keystring = keystring[4 + lk:]
|
|
|
|
if parts[0] != keyparts[0]:
|
|
raise ValueError("Mismatch in openssh public key")
|
|
|
|
# NIST P curves
|
|
if parts[0].startswith(b"ecdsa-sha2-"):
|
|
|
|
for curve_name, curve in _curves.items():
|
|
if curve.openssh is None:
|
|
continue
|
|
if not curve.openssh.startswith("ecdsa-sha2"):
|
|
continue
|
|
middle = tobytes(curve.openssh.split("-")[2])
|
|
if keyparts[1] == middle:
|
|
break
|
|
else:
|
|
raise ValueError("Unsupported ECC curve: " + middle)
|
|
|
|
ecc_key = _import_public_der(keyparts[2], curve_oid=curve.oid)
|
|
|
|
# EdDSA
|
|
elif parts[0] == b"ssh-ed25519":
|
|
x, y = _import_ed25519_public_key(keyparts[1])
|
|
ecc_key = construct(curve="Ed25519", point_x=x, point_y=y)
|
|
else:
|
|
raise ValueError("Unsupported SSH key type: " + parts[0])
|
|
|
|
except (IndexError, TypeError, binascii.Error):
|
|
raise ValueError("Error parsing SSH key type: " + parts[0])
|
|
|
|
return ecc_key
|
|
|
|
|
|
def _import_openssh_private_ecc(data, password):
|
|
|
|
from ._openssh import (import_openssh_private_generic,
|
|
read_bytes, read_string, check_padding)
|
|
|
|
key_type, decrypted = import_openssh_private_generic(data, password)
|
|
|
|
eddsa_keys = {
|
|
"ssh-ed25519": ("Ed25519", _import_ed25519_public_key, 32),
|
|
}
|
|
|
|
# https://datatracker.ietf.org/doc/html/draft-miller-ssh-agent-04
|
|
if key_type.startswith("ecdsa-sha2"):
|
|
|
|
ecdsa_curve_name, decrypted = read_string(decrypted)
|
|
if ecdsa_curve_name not in _curves:
|
|
raise UnsupportedEccFeature("Unsupported ECC curve %s" % ecdsa_curve_name)
|
|
curve = _curves[ecdsa_curve_name]
|
|
modulus_bytes = (curve.modulus_bits + 7) // 8
|
|
|
|
public_key, decrypted = read_bytes(decrypted)
|
|
|
|
if bord(public_key[0]) != 4:
|
|
raise ValueError("Only uncompressed OpenSSH EC keys are supported")
|
|
if len(public_key) != 2 * modulus_bytes + 1:
|
|
raise ValueError("Incorrect public key length")
|
|
|
|
point_x = Integer.from_bytes(public_key[1:1+modulus_bytes])
|
|
point_y = Integer.from_bytes(public_key[1+modulus_bytes:])
|
|
|
|
private_key, decrypted = read_bytes(decrypted)
|
|
d = Integer.from_bytes(private_key)
|
|
|
|
params = {'d': d, 'curve': ecdsa_curve_name}
|
|
|
|
elif key_type in eddsa_keys:
|
|
|
|
curve_name, import_eddsa_public_key, seed_len = eddsa_keys[key_type]
|
|
|
|
public_key, decrypted = read_bytes(decrypted)
|
|
point_x, point_y = import_eddsa_public_key(public_key)
|
|
|
|
private_public_key, decrypted = read_bytes(decrypted)
|
|
seed = private_public_key[:seed_len]
|
|
|
|
params = {'seed': seed, 'curve': curve_name}
|
|
else:
|
|
raise ValueError("Unsupport SSH agent key type:" + key_type)
|
|
|
|
_, padded = read_string(decrypted) # Comment
|
|
check_padding(padded)
|
|
|
|
return construct(point_x=point_x, point_y=point_y, **params)
|
|
|
|
|
|
def _import_ed25519_public_key(encoded):
|
|
"""Import an Ed25519 ECC public key, encoded as raw bytes as described
|
|
in RFC8032_.
|
|
|
|
Args:
|
|
encoded (bytes):
|
|
The Ed25519 public key to import. It must be 32 bytes long.
|
|
|
|
Returns:
|
|
x and y (integer)
|
|
|
|
Raises:
|
|
ValueError: when the given key cannot be parsed.
|
|
|
|
.. _RFC8032: https://datatracker.ietf.org/doc/html/rfc8032
|
|
"""
|
|
|
|
if len(encoded) != 32:
|
|
raise ValueError("Incorrect length. Only Ed25519 public keys are supported.")
|
|
|
|
p = Integer(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffed) # 2**255 - 19
|
|
d = 37095705934669439343138083508754565189542113879843219016388785533085940283555
|
|
|
|
y = bytearray(encoded)
|
|
x_lsb = y[31] >> 7
|
|
y[31] &= 0x7F
|
|
point_y = Integer.from_bytes(y, byteorder='little')
|
|
if point_y >= p:
|
|
raise ValueError("Invalid Ed25519 key (y)")
|
|
if point_y == 1:
|
|
return 0, 1
|
|
|
|
u = (point_y**2 - 1) % p
|
|
v = ((point_y**2 % p) * d + 1) % p
|
|
try:
|
|
v_inv = v.inverse(p)
|
|
x2 = (u * v_inv) % p
|
|
point_x = Integer._tonelli_shanks(x2, p)
|
|
if (point_x & 1) != x_lsb:
|
|
point_x = p - point_x
|
|
except ValueError:
|
|
raise ValueError("Invalid Ed25519 public key")
|
|
return point_x, point_y
|
|
|
|
|
|
def _import_curve25519_public_key(encoded):
|
|
"""Import a Curve25519 ECC public key,
|
|
encoded as raw bytes as described in RFC7748_.
|
|
|
|
Args:
|
|
encoded (bytes):
|
|
The Curve25519 public key to import. It must be 32 bytes long.
|
|
|
|
Returns:
|
|
x (integer)
|
|
|
|
Raises:
|
|
ValueError: when the given key cannot be parsed.
|
|
|
|
.. _RFC7748: https://datatracker.ietf.org/doc/html/rfc7748
|
|
"""
|
|
|
|
if len(encoded) != 32:
|
|
raise ValueError("Incorrect Curve25519 key length")
|
|
|
|
x = bytearray(encoded)
|
|
# RFC 7741, Section 5
|
|
x[31] &= 0x7F
|
|
point_x = Integer.from_bytes(x, byteorder='little')
|
|
|
|
return point_x
|
|
|
|
|
|
def _import_curve448_public_key(encoded):
|
|
"""Import a Curve448 ECC public key,
|
|
encoded as raw bytes as described in RFC7748_.
|
|
|
|
Args:
|
|
encoded (bytes):
|
|
The Curve448 public key to import. It must be 56 bytes long.
|
|
|
|
Returns:
|
|
x (integer)
|
|
|
|
Raises:
|
|
ValueError: when the given key cannot be parsed.
|
|
|
|
.. _RFC7748: https://datatracker.ietf.org/doc/html/rfc7748
|
|
"""
|
|
|
|
if len(encoded) != 56:
|
|
raise ValueError("Incorrect Curve448 key length")
|
|
|
|
point_x = Integer.from_bytes(encoded, byteorder='little')
|
|
|
|
return point_x
|
|
|
|
|
|
def _import_ed448_public_key(encoded):
|
|
"""Import an Ed448 ECC public key, encoded as raw bytes as described
|
|
in RFC8032_.
|
|
|
|
Args:
|
|
encoded (bytes):
|
|
The Ed448 public key to import. It must be 57 bytes long.
|
|
|
|
Returns:
|
|
x and y (integer)
|
|
|
|
Raises:
|
|
ValueError: when the given key cannot be parsed.
|
|
|
|
.. _RFC8032: https://datatracker.ietf.org/doc/html/rfc8032
|
|
"""
|
|
|
|
if len(encoded) != 57:
|
|
raise ValueError("Incorrect length. Only Ed448 public keys are supported.")
|
|
|
|
p = _curves['curve448'].p
|
|
d = p - 39081
|
|
|
|
y = encoded[:56]
|
|
x_lsb = bord(encoded[56]) >> 7
|
|
point_y = Integer.from_bytes(y, byteorder='little')
|
|
if point_y >= p:
|
|
raise ValueError("Invalid Ed448 key (y)")
|
|
if point_y == 1:
|
|
return 0, 1
|
|
|
|
u = (point_y**2 - 1) % p
|
|
v = ((point_y**2 % p) * d - 1) % p
|
|
try:
|
|
v_inv = v.inverse(p)
|
|
x2 = (u * v_inv) % p
|
|
point_x = Integer._tonelli_shanks(x2, p)
|
|
if (point_x & 1) != x_lsb:
|
|
point_x = p - point_x
|
|
except ValueError:
|
|
raise ValueError("Invalid Ed448 public key")
|
|
return point_x, point_y
|
|
|
|
|
|
def import_key(encoded, passphrase=None, curve_name=None):
|
|
"""Import an ECC key (public or private).
|
|
|
|
Args:
|
|
encoded (bytes or multi-line string):
|
|
The ECC key to import.
|
|
The function will try to automatically detect the right format.
|
|
|
|
Supported formats for an ECC **public** key:
|
|
|
|
* X.509 certificate: binary (DER) or ASCII (PEM).
|
|
* X.509 ``subjectPublicKeyInfo``: binary (DER) or ASCII (PEM).
|
|
* SEC1_ (or X9.62), as ``bytes``. NIST P curves only.
|
|
You must also provide the ``curve_name`` (with a value from the `ECC table`_)
|
|
* OpenSSH line, defined in RFC5656_ and RFC8709_ (ASCII).
|
|
This is normally the content of files like ``~/.ssh/id_ecdsa.pub``.
|
|
|
|
Supported formats for an ECC **private** key:
|
|
|
|
* A binary ``ECPrivateKey`` structure, as defined in `RFC5915`_ (DER).
|
|
NIST P curves only.
|
|
* A `PKCS#8`_ structure (or the more recent Asymmetric Key
|
|
Package, RFC5958_): binary (DER) or ASCII (PEM).
|
|
* `OpenSSH 6.5`_ and newer versions (ASCII).
|
|
|
|
Private keys can be in the clear or password-protected.
|
|
|
|
For details about the PEM encoding, see `RFC1421`_/`RFC1423`_.
|
|
|
|
passphrase (byte string):
|
|
The passphrase to use for decrypting a private key.
|
|
Encryption may be applied protected at the PEM level (not recommended)
|
|
or at the PKCS#8 level (recommended).
|
|
This parameter is ignored if the key in input is not encrypted.
|
|
|
|
curve_name (string):
|
|
For a SEC1 encoding only. This is the name of the curve,
|
|
as defined in the `ECC table`_.
|
|
|
|
.. note::
|
|
|
|
To import EdDSA private and public keys, when encoded as raw ``bytes``, use:
|
|
|
|
* :func:`Crypto.Signature.eddsa.import_public_key`, or
|
|
* :func:`Crypto.Signature.eddsa.import_private_key`.
|
|
|
|
.. note::
|
|
|
|
To import X25519/X448 private and public keys, when encoded as raw ``bytes``, use:
|
|
|
|
* :func:`Crypto.Protocol.DH.import_x25519_public_key`
|
|
* :func:`Crypto.Protocol.DH.import_x25519_private_key`
|
|
* :func:`Crypto.Protocol.DH.import_x448_public_key`
|
|
* :func:`Crypto.Protocol.DH.import_x448_private_key`
|
|
|
|
Returns:
|
|
:class:`EccKey` : a new ECC key object
|
|
|
|
Raises:
|
|
ValueError: when the given key cannot be parsed (possibly because
|
|
the pass phrase is wrong).
|
|
|
|
.. _RFC1421: https://datatracker.ietf.org/doc/html/rfc1421
|
|
.. _RFC1423: https://datatracker.ietf.org/doc/html/rfc1423
|
|
.. _RFC5915: https://datatracker.ietf.org/doc/html/rfc5915
|
|
.. _RFC5656: https://datatracker.ietf.org/doc/html/rfc5656
|
|
.. _RFC8709: https://datatracker.ietf.org/doc/html/rfc8709
|
|
.. _RFC5958: https://datatracker.ietf.org/doc/html/rfc5958
|
|
.. _`PKCS#8`: https://datatracker.ietf.org/doc/html/rfc5208
|
|
.. _`OpenSSH 6.5`: https://flak.tedunangst.com/post/new-openssh-key-format-and-bcrypt-pbkdf
|
|
.. _SEC1: https://www.secg.org/sec1-v2.pdf
|
|
"""
|
|
|
|
from Crypto.IO import PEM
|
|
|
|
encoded = tobytes(encoded)
|
|
if passphrase is not None:
|
|
passphrase = tobytes(passphrase)
|
|
|
|
# PEM
|
|
if encoded.startswith(b'-----BEGIN OPENSSH PRIVATE KEY'):
|
|
text_encoded = tostr(encoded)
|
|
openssh_encoded, marker, enc_flag = PEM.decode(text_encoded, passphrase)
|
|
result = _import_openssh_private_ecc(openssh_encoded, passphrase)
|
|
return result
|
|
|
|
elif encoded.startswith(b'-----'):
|
|
|
|
text_encoded = tostr(encoded)
|
|
|
|
# Remove any EC PARAMETERS section
|
|
# Ignore its content because the curve type must be already given in the key
|
|
ecparams_start = "-----BEGIN EC PARAMETERS-----"
|
|
ecparams_end = "-----END EC PARAMETERS-----"
|
|
text_encoded = re.sub(ecparams_start + ".*?" + ecparams_end, "",
|
|
text_encoded,
|
|
flags=re.DOTALL)
|
|
|
|
der_encoded, marker, enc_flag = PEM.decode(text_encoded, passphrase)
|
|
if enc_flag:
|
|
passphrase = None
|
|
try:
|
|
result = _import_der(der_encoded, passphrase)
|
|
except UnsupportedEccFeature as uef:
|
|
raise uef
|
|
except ValueError:
|
|
raise ValueError("Invalid DER encoding inside the PEM file")
|
|
return result
|
|
|
|
# OpenSSH
|
|
if encoded.startswith((b'ecdsa-sha2-', b'ssh-ed25519')):
|
|
return _import_openssh_public(encoded)
|
|
|
|
# DER
|
|
if len(encoded) > 0 and bord(encoded[0]) == 0x30:
|
|
return _import_der(encoded, passphrase)
|
|
|
|
# SEC1
|
|
if len(encoded) > 0 and bord(encoded[0]) in (0x02, 0x03, 0x04):
|
|
if curve_name is None:
|
|
raise ValueError("No curve name was provided")
|
|
return _import_public_der(encoded, curve_name=curve_name)
|
|
|
|
raise ValueError("ECC key format is not supported")
|
|
|
|
|
|
if __name__ == "__main__":
|
|
|
|
import time
|
|
|
|
d = 0xc51e4753afdec1e6b6c6a5b992f43f8dd0c7a8933072708b6522468b2ffb06fd
|
|
|
|
point = _curves['p256'].G.copy()
|
|
count = 3000
|
|
|
|
start = time.time()
|
|
for x in range(count):
|
|
pointX = point * d
|
|
print("(P-256 G)", (time.time() - start) / count * 1000, "ms")
|
|
|
|
start = time.time()
|
|
for x in range(count):
|
|
pointX = pointX * d
|
|
print("(P-256 arbitrary point)", (time.time() - start) / count * 1000, "ms")
|