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Diffstat (limited to 'freezed_deps/ecdsa/ecdh.py')
| -rw-r--r-- | freezed_deps/ecdsa/ecdh.py | 306 |
1 files changed, 0 insertions, 306 deletions
diff --git a/freezed_deps/ecdsa/ecdh.py b/freezed_deps/ecdsa/ecdh.py deleted file mode 100644 index 88848f5..0000000 --- a/freezed_deps/ecdsa/ecdh.py +++ /dev/null @@ -1,306 +0,0 @@ -""" -Class for performing Elliptic-curve Diffie-Hellman (ECDH) operations. -""" - -from .util import number_to_string -from .ellipticcurve import INFINITY -from .keys import SigningKey, VerifyingKey - - -__all__ = ["ECDH", "NoKeyError", "NoCurveError", "InvalidCurveError", - "InvalidSharedSecretError"] - - -class NoKeyError(Exception): - """ECDH. Key not found but it is needed for operation.""" - - pass - - -class NoCurveError(Exception): - """ECDH. Curve not set but it is needed for operation.""" - - pass - - -class InvalidCurveError(Exception): - """ECDH. Raised in case the public and private keys use different curves.""" - - pass - - -class InvalidSharedSecretError(Exception): - """ECDH. Raised in case the shared secret we obtained is an INFINITY.""" - - pass - - -class ECDH(object): - """ - Elliptic-curve Diffie-Hellman (ECDH). A key agreement protocol. - - Allows two parties, each having an elliptic-curve public-private key - pair, to establish a shared secret over an insecure channel - """"" - - def __init__(self, curve=None, private_key=None, public_key=None): - """ - ECDH init. - - Call can be initialised without parameters, then the first operation - (loading either key) will set the used curve. - All parameters must be ultimately set before shared secret - calculation will be allowed. - - :param curve: curve for operations - :type curve: Curve - :param private_key: `my` private key for ECDH - :type private_key: SigningKey - :param public_key: `their` public key for ECDH - :type public_key: VerifyingKey - """ - self.curve = curve - self.private_key = None - self.public_key = None - if private_key: - self.load_private_key(private_key) - if public_key: - self.load_received_public_key(public_key) - - def _get_shared_secret(self, remote_public_key): - if not self.private_key: - raise NoKeyError( - "Private key needs to be set to create shared secret") - if not self.public_key: - raise NoKeyError( - "Public key needs to be set to create shared secret") - if not (self.private_key.curve == self.curve == remote_public_key.curve): - raise InvalidCurveError( - "Curves for public key and private key is not equal.") - - # shared secret = PUBKEYtheirs * PRIVATEKEYours - result = remote_public_key.pubkey.point * self.private_key.privkey.secret_multiplier - if result == INFINITY: - raise InvalidSharedSecretError( - "Invalid shared secret (INFINITY).") - - return result.x() - - def set_curve(self, key_curve): - """ - Set the working curve for ecdh operations. - - :param key_curve: curve from `curves` module - :type key_curve: Curve - """ - self.curve = key_curve - - def generate_private_key(self): - """ - Generate local private key for ecdh operation with curve that was set. - - :raises NoCurveError: Curve must be set before key generation. - - :return: public (verifying) key from this private key. - :rtype: VerifyingKey object - """ - if not self.curve: - raise NoCurveError("Curve must be set prior to key generation.") - return self.load_private_key(SigningKey.generate(curve=self.curve)) - - def load_private_key(self, private_key): - """ - Load private key from SigningKey (keys.py) object. - - Needs to have the same curve as was set with set_curve method. - If curve is not set - it sets from this SigningKey - - :param private_key: Initialised SigningKey class - :type private_key: SigningKey - - :raises InvalidCurveError: private_key curve not the same as self.curve - - :return: public (verifying) key from this private key. - :rtype: VerifyingKey object - """ - if not self.curve: - self.curve = private_key.curve - if self.curve != private_key.curve: - raise InvalidCurveError("Curve mismatch.") - self.private_key = private_key - return self.private_key.get_verifying_key() - - def load_private_key_bytes(self, private_key): - """ - Load private key from byte string. - - Uses current curve and checks if the provided key matches - the curve of ECDH key agreement. - Key loads via from_string method of SigningKey class - - :param private_key: private key in bytes string format - :type private_key: :term:`bytes-like object` - - :raises NoCurveError: Curve must be set before loading. - - :return: public (verifying) key from this private key. - :rtype: VerifyingKey object - """ - if not self.curve: - raise NoCurveError("Curve must be set prior to key load.") - return self.load_private_key( - SigningKey.from_string(private_key, curve=self.curve)) - - def load_private_key_der(self, private_key_der): - """ - Load private key from DER byte string. - - Compares the curve of the DER-encoded key with the ECDH set curve, - uses the former if unset. - - Note, the only DER format supported is the RFC5915 - Look at keys.py:SigningKey.from_der() - - :param private_key_der: string with the DER encoding of private ECDSA key - :type private_key_der: string - - :raises InvalidCurveError: private_key curve not the same as self.curve - - :return: public (verifying) key from this private key. - :rtype: VerifyingKey object - """ - return self.load_private_key(SigningKey.from_der(private_key_der)) - - def load_private_key_pem(self, private_key_pem): - """ - Load private key from PEM string. - - Compares the curve of the DER-encoded key with the ECDH set curve, - uses the former if unset. - - Note, the only PEM format supported is the RFC5915 - Look at keys.py:SigningKey.from_pem() - it needs to have `EC PRIVATE KEY` section - - :param private_key_pem: string with PEM-encoded private ECDSA key - :type private_key_pem: string - - :raises InvalidCurveError: private_key curve not the same as self.curve - - :return: public (verifying) key from this private key. - :rtype: VerifyingKey object - """ - return self.load_private_key(SigningKey.from_pem(private_key_pem)) - - def get_public_key(self): - """ - Provides a public key that matches the local private key. - - Needs to be sent to the remote party. - - :return: public (verifying) key from local private key. - :rtype: VerifyingKey object - """ - return self.private_key.get_verifying_key() - - def load_received_public_key(self, public_key): - """ - Load public key from VerifyingKey (keys.py) object. - - Needs to have the same curve as set as current for ecdh operation. - If curve is not set - it sets it from VerifyingKey. - - :param public_key: Initialised VerifyingKey class - :type public_key: VerifyingKey - - :raises InvalidCurveError: public_key curve not the same as self.curve - """ - if not self.curve: - self.curve = public_key.curve - if self.curve != public_key.curve: - raise InvalidCurveError("Curve mismatch.") - self.public_key = public_key - - def load_received_public_key_bytes(self, public_key_str): - """ - Load public key from byte string. - - Uses current curve and checks if key length corresponds to - the current curve. - Key loads via from_string method of VerifyingKey class - - :param public_key_str: public key in bytes string format - :type public_key_str: :term:`bytes-like object` - """ - return self.load_received_public_key( - VerifyingKey.from_string(public_key_str, self.curve)) - - def load_received_public_key_der(self, public_key_der): - """ - Load public key from DER byte string. - - Compares the curve of the DER-encoded key with the ECDH set curve, - uses the former if unset. - - Note, the only DER format supported is the RFC5912 - Look at keys.py:VerifyingKey.from_der() - - :param public_key_der: string with the DER encoding of public ECDSA key - :type public_key_der: string - - :raises InvalidCurveError: public_key curve not the same as self.curve - """ - return self.load_received_public_key(VerifyingKey.from_der(public_key_der)) - - def load_received_public_key_pem(self, public_key_pem): - """ - Load public key from PEM string. - - Compares the curve of the PEM-encoded key with the ECDH set curve, - uses the former if unset. - - Note, the only PEM format supported is the RFC5912 - Look at keys.py:VerifyingKey.from_pem() - - :param public_key_pem: string with PEM-encoded public ECDSA key - :type public_key_pem: string - - :raises InvalidCurveError: public_key curve not the same as self.curve - """ - return self.load_received_public_key(VerifyingKey.from_pem(public_key_pem)) - - def generate_sharedsecret_bytes(self): - """ - Generate shared secret from local private key and remote public key. - - The objects needs to have both private key and received public key - before generation is allowed. - - :raises InvalidCurveError: public_key curve not the same as self.curve - :raises NoKeyError: public_key or private_key is not set - - :return: shared secret - :rtype: byte string - """ - return number_to_string( - self.generate_sharedsecret(), - self.private_key.curve.order) - - def generate_sharedsecret(self): - """ - Generate shared secret from local private key and remote public key. - - The objects needs to have both private key and received public key - before generation is allowed. - - It's the same for local and remote party. - shared secret(local private key, remote public key ) == - shared secret (local public key, remote private key) - - :raises InvalidCurveError: public_key curve not the same as self.curve - :raises NoKeyError: public_key or private_key is not set - - :return: shared secret - :rtype: int - """ - return self._get_shared_secret(self.public_key) |