Source code for M2Crypto.EC

from __future__ import absolute_import

"""
M2Crypto wrapper for OpenSSL ECDH/ECDSA API.

@requires: OpenSSL 0.9.8 or newer

Copyright (c) 1999-2003 Ng Pheng Siong. All rights reserved.

Portions copyright (c) 2005-2006 Vrije Universiteit Amsterdam.
All rights reserved."""

from M2Crypto import BIO, Err, m2, util
from typing import AnyStr, Callable, Dict, Optional, Tuple, Union  # noqa

EC_Key = bytes


[docs] class ECError(Exception): pass
m2.ec_init(ECError) # Curve identifier constants NID_secp112r1 = m2.NID_secp112r1 # type: int NID_secp112r2 = m2.NID_secp112r2 # type: int NID_secp128r1 = m2.NID_secp128r1 # type: int NID_secp128r2 = m2.NID_secp128r2 # type: int NID_secp160k1 = m2.NID_secp160k1 # type: int NID_secp160r1 = m2.NID_secp160r1 # type: int NID_secp160r2 = m2.NID_secp160r2 # type: int NID_secp192k1 = m2.NID_secp192k1 # type: int NID_secp224k1 = m2.NID_secp224k1 # type: int NID_secp224r1 = m2.NID_secp224r1 # type: int NID_secp256k1 = m2.NID_secp256k1 # type: int NID_secp384r1 = m2.NID_secp384r1 # type: int NID_secp521r1 = m2.NID_secp521r1 # type: int NID_sect113r1 = m2.NID_sect113r1 # type: int NID_sect113r2 = m2.NID_sect113r2 # type: int NID_sect131r1 = m2.NID_sect131r1 # type: int NID_sect131r2 = m2.NID_sect131r2 # type: int NID_sect163k1 = m2.NID_sect163k1 # type: int NID_sect163r1 = m2.NID_sect163r1 # type: int NID_sect163r2 = m2.NID_sect163r2 # type: int NID_sect193r1 = m2.NID_sect193r1 # type: int NID_sect193r2 = m2.NID_sect193r2 # type: int # default for secg.org TLS test server NID_sect233k1 = m2.NID_sect233k1 # type: int NID_sect233r1 = m2.NID_sect233r1 # type: int NID_sect239k1 = m2.NID_sect239k1 # type: int NID_sect283k1 = m2.NID_sect283k1 # type: int NID_sect283r1 = m2.NID_sect283r1 # type: int NID_sect409k1 = m2.NID_sect409k1 # type: int NID_sect409r1 = m2.NID_sect409r1 # type: int NID_sect571k1 = m2.NID_sect571k1 # type: int NID_sect571r1 = m2.NID_sect571r1 # type: int NID_prime192v1 = m2.NID_X9_62_prime192v1 # type: int NID_prime192v2 = m2.NID_X9_62_prime192v2 # type: int NID_prime192v3 = m2.NID_X9_62_prime192v3 # type: int NID_prime239v1 = m2.NID_X9_62_prime239v1 # type: int NID_prime239v2 = m2.NID_X9_62_prime239v2 # type: int NID_prime239v3 = m2.NID_X9_62_prime239v3 # type: int NID_prime256v1 = m2.NID_X9_62_prime256v1 # type: int NID_c2pnb163v1 = m2.NID_X9_62_c2pnb163v1 # type: int NID_c2pnb163v2 = m2.NID_X9_62_c2pnb163v2 # type: int NID_c2pnb163v3 = m2.NID_X9_62_c2pnb163v3 # type: int NID_c2pnb176v1 = m2.NID_X9_62_c2pnb176v1 # type: int NID_c2tnb191v1 = m2.NID_X9_62_c2tnb191v1 # type: int NID_c2tnb191v2 = m2.NID_X9_62_c2tnb191v2 # type: int NID_c2tnb191v3 = m2.NID_X9_62_c2tnb191v3 # type: int NID_c2pnb208w1 = m2.NID_X9_62_c2pnb208w1 # type: int NID_c2tnb239v1 = m2.NID_X9_62_c2tnb239v1 # type: int NID_c2tnb239v2 = m2.NID_X9_62_c2tnb239v2 # type: int NID_c2tnb239v3 = m2.NID_X9_62_c2tnb239v3 # type: int NID_c2pnb272w1 = m2.NID_X9_62_c2pnb272w1 # type: int NID_c2pnb304w1 = m2.NID_X9_62_c2pnb304w1 # type: int NID_c2tnb359v1 = m2.NID_X9_62_c2tnb359v1 # type: int NID_c2pnb368w1 = m2.NID_X9_62_c2pnb368w1 # type: int NID_c2tnb431r1 = m2.NID_X9_62_c2tnb431r1 # type: int # To preserve compatibility with older names NID_X9_62_prime192v1 = NID_prime192v1 # type: int NID_X9_62_prime192v2 = NID_prime192v2 # type: int NID_X9_62_prime192v3 = NID_prime192v3 # type: int NID_X9_62_prime239v1 = NID_prime239v1 # type: int NID_X9_62_prime239v2 = NID_prime239v2 # type: int NID_X9_62_prime239v3 = NID_prime239v3 # type: int NID_X9_62_prime256v1 = NID_prime256v1 # type: int NID_X9_62_c2pnb163v1 = NID_c2pnb163v1 # type: int NID_X9_62_c2pnb163v2 = NID_c2pnb163v2 # type: int NID_X9_62_c2pnb163v3 = NID_c2pnb163v3 # type: int NID_X9_62_c2pnb176v1 = NID_c2pnb176v1 # type: int NID_X9_62_c2tnb191v1 = NID_c2tnb191v1 # type: int NID_X9_62_c2tnb191v2 = NID_c2tnb191v2 # type: int NID_X9_62_c2tnb191v3 = NID_c2tnb191v3 # type: int NID_X9_62_c2pnb208w1 = NID_c2pnb208w1 # type: int NID_X9_62_c2tnb239v1 = NID_c2tnb239v1 # type: int NID_X9_62_c2tnb239v2 = NID_c2tnb239v2 # type: int NID_X9_62_c2tnb239v3 = NID_c2tnb239v3 # type: int NID_X9_62_c2pnb272w1 = NID_c2pnb272w1 # type: int NID_X9_62_c2pnb304w1 = NID_c2pnb304w1 # type: int NID_X9_62_c2tnb359v1 = NID_c2tnb359v1 # type: int NID_X9_62_c2pnb368w1 = NID_c2pnb368w1 # type: int NID_X9_62_c2tnb431r1 = NID_c2tnb431r1 # type: int NID_wap_wsg_idm_ecid_wtls1 = m2.NID_wap_wsg_idm_ecid_wtls1 # type: int NID_wap_wsg_idm_ecid_wtls3 = m2.NID_wap_wsg_idm_ecid_wtls3 # type: int NID_wap_wsg_idm_ecid_wtls4 = m2.NID_wap_wsg_idm_ecid_wtls4 # type: int NID_wap_wsg_idm_ecid_wtls5 = m2.NID_wap_wsg_idm_ecid_wtls5 # type: int NID_wap_wsg_idm_ecid_wtls6 = m2.NID_wap_wsg_idm_ecid_wtls6 # type: int NID_wap_wsg_idm_ecid_wtls7 = m2.NID_wap_wsg_idm_ecid_wtls7 # type: int NID_wap_wsg_idm_ecid_wtls8 = m2.NID_wap_wsg_idm_ecid_wtls8 # type: int NID_wap_wsg_idm_ecid_wtls9 = m2.NID_wap_wsg_idm_ecid_wtls9 # type: int NID_wap_wsg_idm_ecid_wtls10 = m2.NID_wap_wsg_idm_ecid_wtls10 # type: int NID_wap_wsg_idm_ecid_wtls11 = m2.NID_wap_wsg_idm_ecid_wtls11 # type: int NID_wap_wsg_idm_ecid_wtls12 = m2.NID_wap_wsg_idm_ecid_wtls12 # type: int # The following two curves, according to OpenSSL, have a # "Questionable extension field!" and are not supported by # the OpenSSL inverse function. ECError: no inverse. # As such they cannot be used for signing. They might, # however, be usable for encryption but that has not # been tested. Until thir usefulness can be established, # they are not supported at this time. # NID_ipsec3 = m2.NID_ipsec3 # NID_ipsec4 = m2.NID_ipsec4
[docs] class EC(object): """ Object interface to a EC key pair. """ m2_ec_key_free = m2.ec_key_free def __init__(self, ec, _pyfree=0): # type: (EC, int) -> None assert m2.ec_key_type_check(ec), "'ec' type error" self.ec = ec self._pyfree = _pyfree def __del__(self): # type: () -> None if getattr(self, '_pyfree', 0): self.m2_ec_key_free(self.ec) def __len__(self): # type: () -> int assert m2.ec_key_type_check(self.ec), "'ec' type error" return m2.ec_key_keylen(self.ec)
[docs] def gen_key(self): # type: () -> int """ Generates the key pair from its parameters. Use:: keypair = EC.gen_params(curve) keypair.gen_key() to create an EC key pair. """ assert m2.ec_key_type_check(self.ec), "'ec' type error" m2.ec_key_gen_key(self.ec)
[docs] def pub(self): # type: () -> EC_pub # Don't let python free return EC_pub(self.ec, 0)
[docs] def sign_dsa(self, digest): # type: (bytes) -> Tuple[bytes, bytes] """ Sign the given digest using ECDSA. Returns a tuple (r,s), the two ECDSA signature parameters. """ assert self._check_key_type(), "'ec' type error" return m2.ecdsa_sign(self.ec, digest)
[docs] def verify_dsa(self, digest, r, s): # type: (bytes, bytes, bytes) -> int """ Verify the given digest using ECDSA. r and s are the ECDSA signature parameters. """ assert self._check_key_type(), "'ec' type error" return m2.ecdsa_verify(self.ec, digest, r, s)
[docs] def sign_dsa_asn1(self, digest): # type: (bytes) -> bytes assert self._check_key_type(), "'ec' type error" return m2.ecdsa_sign_asn1(self.ec, digest)
[docs] def verify_dsa_asn1(self, digest, blob): assert self._check_key_type(), "'ec' type error" return m2.ecdsa_verify_asn1(self.ec, digest, blob)
[docs] def compute_dh_key(self, pub_key): # type: (EC) -> Optional[bytes] """ Compute the ECDH shared key of this key pair and the given public key object. They must both use the same curve. Returns the shared key in binary as a buffer object. No Key Derivation Function is applied. """ assert self.check_key(), 'key is not initialised' return m2.ecdh_compute_key(self.ec, pub_key.ec)
[docs] def save_key_bio(self, bio, cipher='aes_128_cbc', callback=util.passphrase_callback): # type: (BIO.BIO, Optional[str], Callable) -> int """ Save the key pair to an M2Crypto.BIO.BIO object in PEM format. :param bio: M2Crypto.BIO.BIO object to save key to. :param cipher: Symmetric cipher to protect the key. The default cipher is 'aes_128_cbc'. If cipher is None, then the key is saved in the clear. :param callback: A Python callable object that is invoked to acquire a passphrase with which to protect the key. The default is util.passphrase_callback. """ if cipher is None: return m2.ec_key_write_bio_no_cipher(self.ec, bio._ptr(), callback) else: ciph = getattr(m2, cipher, None) if ciph is None: raise ValueError('not such cipher %s' % cipher) return m2.ec_key_write_bio(self.ec, bio._ptr(), ciph(), callback)
[docs] def save_key(self, file, cipher='aes_128_cbc', callback=util.passphrase_callback): # type: (AnyStr, Optional[str], Callable) -> int """ Save the key pair to a file in PEM format. :param file: Name of filename to save key to. :param cipher: Symmetric cipher to protect the key. The default cipher is 'aes_128_cbc'. If cipher is None, then the key is saved in the clear. :param callback: A Python callable object that is invoked to acquire a passphrase with which to protect the key. The default is util.passphrase_callback. """ with BIO.openfile(file, 'wb') as bio: return self.save_key_bio(bio, cipher, callback)
[docs] def save_pub_key_bio(self, bio): # type: (BIO.BIO) -> int """ Save the public key to an M2Crypto.BIO.BIO object in PEM format. :param bio: M2Crypto.BIO.BIO object to save key to. """ return m2.ec_key_write_pubkey(self.ec, bio._ptr())
[docs] def save_pub_key(self, file): # type: (AnyStr) -> int """ Save the public key to a filename in PEM format. :param file: Name of filename to save key to. """ with BIO.openfile(file, 'wb') as bio: return m2.ec_key_write_pubkey(self.ec, bio._ptr())
[docs] def as_pem(self, cipher='aes_128_cbc', callback=util.passphrase_callback): """ Returns the key(pair) as a string in PEM format. If no password is passed and the cipher is set it exits with error """ with BIO.MemoryBuffer() as bio: self.save_key_bio(bio, cipher, callback) return bio.read()
def _check_key_type(self): # type: () -> int return m2.ec_key_type_check(self.ec)
[docs] def check_key(self): # type: () -> int assert m2.ec_key_type_check(self.ec), "'ec' type error" return m2.ec_key_check_key(self.ec)
[docs] class EC_pub(EC): """ Object interface to an EC public key. ((don't like this implementation inheritance)) """ def __init__(self, ec, _pyfree=0): # type: (EC, int) -> None EC.__init__(self, ec, _pyfree) self.der = None # type: Optional[bytes]
[docs] def get_der(self): # type: () -> bytes """ Returns the public key in DER format as a buffer object. """ assert self.check_key(), 'key is not initialised' if self.der is None: self.der = m2.ec_key_get_public_der(self.ec) return self.der
[docs] def get_key(self): # type: () -> bytes """ Returns the public key as a byte string. """ assert self.check_key(), 'key is not initialised' return m2.ec_key_get_public_key(self.ec)
[docs] def as_pem(self): """ Returns the key(pair) as a string in PEM format. If no password is passed and the cipher is set it exits with error """ with BIO.MemoryBuffer() as bio: self.save_key_bio(bio) return bio.read()
save_key = EC.save_pub_key save_key_bio = EC.save_pub_key_bio
[docs] def gen_params(curve): # type: (int) -> EC """ Factory function that generates EC parameters and instantiates a EC object from the output. :param curve: This is the OpenSSL nid of the curve to use. """ assert curve in [x['NID'] for x in m2.ec_get_builtin_curves()], \ 'Elliptic curve %s is not available on this system.' % \ m2.obj_nid2sn(curve) return EC(m2.ec_key_new_by_curve_name(curve), 1)
[docs] def load_key(file, callback=util.passphrase_callback): # type: (AnyStr, Callable) -> EC """ Factory function that instantiates a EC object. :param file: Names the filename that contains the PEM representation of the EC key pair. :param callback: Python callback object that will be invoked if the EC key pair is passphrase-protected. """ with BIO.openfile(file) as bio: return load_key_bio(bio, callback)
[docs] def load_key_string(string, callback=util.passphrase_callback): # type: (str, Callable) -> EC """ Load an EC key pair from a string. :param string: String containing EC key pair in PEM format. :param callback: A Python callable object that is invoked to acquire a passphrase with which to unlock the key. The default is util.passphrase_callback. :return: M2Crypto.EC.EC object. """ with BIO.MemoryBuffer(string) as bio: return load_key_bio(bio, callback)
[docs] def load_key_bio(bio, callback=util.passphrase_callback): # type: (BIO.BIO, Callable) -> EC """ Factory function that instantiates a EC object. :param bio: M2Crypto.BIO object that contains the PEM representation of the EC key pair. :param callback: Python callback object that will be invoked if the EC key pair is passphrase-protected. """ return EC(m2.ec_key_read_bio(bio._ptr(), callback), 1)
[docs] def load_pub_key(file): # type: (AnyStr) -> EC_pub """ Load an EC public key from filename. :param file: Name of filename containing EC public key in PEM format. :return: M2Crypto.EC.EC_pub object. """ with BIO.openfile(file) as bio: return load_pub_key_bio(bio)
[docs] def load_key_string_pubkey(string, callback=util.passphrase_callback): # type: (str, Callable) -> EC.PKey """ Load an M2Crypto.EC.PKey from a public key as a string. :param string: String containing the key in PEM format. :param callback: A Python callable object that is invoked to acquire a passphrase with which to protect the key. :return: M2Crypto.EC.PKey object. """ from M2Crypto.EVP import load_key_bio_pubkey with BIO.MemoryBuffer(string) as bio: return load_key_bio_pubkey(bio, callback)
[docs] def load_pub_key_bio(bio): # type: (BIO.BIO) -> EC_pub """ Load an EC public key from an M2Crypto.BIO.BIO object. :param bio: M2Crypto.BIO.BIO object containing EC public key in PEM format. :return: M2Crypto.EC.EC_pub object. """ ec = m2.ec_key_read_pubkey(bio._ptr()) if ec is None: ec_error() return EC_pub(ec, 1)
[docs] def ec_error(): # type: () -> ECError raise ECError(Err.get_error_message())
[docs] def pub_key_from_der(der): # type: (bytes) -> EC_pub """ Create EC_pub from DER. """ return EC_pub(m2.ec_key_from_pubkey_der(der), 1)
[docs] def pub_key_from_params(curve, bytes): # type: (bytes, bytes) -> EC_pub """ Create EC_pub from curve name and octet string. """ return EC_pub(m2.ec_key_from_pubkey_params(curve, bytes), 1)
[docs] def get_builtin_curves(): # type: () -> Tuple[Dict[str, Union[int, str]]] return m2.ec_get_builtin_curves()