Beispiel #1
0
def verify_digest(digest_hex,
                  pubkey_hex,
                  sigb64,
                  curve=fastecdsa.curve.secp256k1,
                  hashfunc=hashlib.sha256):
    """
    Verify a digest and signature with ECDSA
    Return True if it matches
    """

    Q = decode_pubkey_hex(str(pubkey_hex))
    r, s = decode_signature(sigb64)

    # validate Q, r, s
    if not curve.is_point_on_curve(Q):
        raise fastecdsa.ecdsa.EcdsaError(
            'Invalid public key, point is not on curve {}'.format(curve.name))
    elif r > curve.q or r < 1:
        raise fastecdsa.ecdsa.EcdsaError(
            'Invalid Signature: r is not a positive integer smaller than the curve order'
        )
    elif s > curve.q or s < 1:
        raise fastecdsa.ecdsa.EcdsaError(
            'Invalid Signature: s is not a positive integer smaller than the curve order'
        )

    qx, qy = Q
    return _ecdsa.verify(str(r), str(s), digest_hex, str(qx), str(qy),
                         curve.name)
Beispiel #2
0
def verify(
        sig: SigType, msg: MsgTypes, Q: Point, curve: Curve = P256, hashfunc=sha256, prehashed: bool = False) -> bool:
    """Verify a message signature using the elliptic curve digital signature algorithm.

    The elliptic curve signature algorithm is described in full in FIPS 186-4 Section 6. Please
    refer to http://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.186-4.pdf for more information.

    Args:
        |  sig (int, int): The signature for the message.
        |  msg (str|bytes|bytearray): A message to be signed.
        |  Q (fastecdsa.point.Point): The ECDSA public key of the signer.
        |  curve (fastecdsa.curve.Curve): The curve to be used to sign the message.
        |  hashfunc (_hashlib.HASH): The hash function used to compress the message.
        |  prehashed (bool): The message being passed has already been hashed by :code:`hashfunc`.

    Returns:
        bool: True if the signature is valid, False otherwise.

    Raises:
        fastecdsa.ecdsa.EcdsaError: If the signature or public key are invalid. Invalid signature
            in this case means that it has values less than 1 or greater than the curve order.
    """
    if isinstance(Q, tuple):
        Q = Point(Q[0], Q[1], curve)
    r, s = sig

    # validate Q, r, s (Q should be validated in constructor of Point already but double check)
    if not curve.is_point_on_curve((Q.x, Q.y)):
        raise EcdsaError('Invalid public key, point is not on curve {}'.format(curve.name))
    elif r > curve.q or r < 1:
        raise EcdsaError(
            'Invalid Signature: r is not a positive integer smaller than the curve order')
    elif s > curve.q or s < 1:
        raise EcdsaError(
            'Invalid Signature: s is not a positive integer smaller than the curve order')

    if prehashed:
        hashed = hexlify(msg).decode()
    else:
        hashed = hashfunc(msg_bytes(msg)).hexdigest()

    return _ecdsa.verify(
        str(r),
        str(s),
        hashed,
        str(Q.x),
        str(Q.y),
        str(curve.p),
        str(curve.a),
        str(curve.b),
        str(curve.q),
        str(curve.gx),
        str(curve.gy)
    )
Beispiel #3
0
def verify(sig, msg, Q, curve=P256, hashfunc=sha256):
    """Verify a message signature using the elliptic curve digital signature algorithm.

    The elliptic curve signature algorithm is described in full in FIPS 186-4 Section 6. Please
    refer to http://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.186-4.pdf for more information.

    Args:
        |  sig (long, long): The signature for the message.
        |  msg (str): A message to be signed.
        |  Q (fastecdsa.point.Point): The ECDSA public key of the signer.
        |  curve (fastecdsa.curve.Curve): The curve to be used to sign the message.
        |  hashfunc (_hashlib.HASH): The hash function used to compress the message.

    Returns:
        bool: True if the signature is valid, False otherwise.

    Raises:
        fastecdsa.ecdsa.EcdsaError: If the signature or public key are invalid. Invalid signature
            in this case means that it has values less than 1 or greater than the curve order.
    """
    if isinstance(Q, tuple):
        Q = Point(Q[0], Q[1], curve)
    r, s = sig

    # validate Q, r, s (Q should be validated in constructor of Point already but double check)
    if not curve.is_point_on_curve((Q.x, Q.y)):
        raise EcdsaError('Invalid public key, point is not on curve {}'.format(
            curve.name))
    elif r > curve.q or r < 1:
        raise EcdsaError(
            'Invalid Signature: r is not a positive integer smaller than the curve order'
        )
    elif s > curve.q or s < 1:
        raise EcdsaError(
            'Invalid Signature: s is not a positive integer smaller than the curve order'
        )
    hashed = str(0x0d80b4919e2edb5e1ba3e619e8b60bfad25d16c4deec05a7)
    #hashed = hashfunc(msg.encode()).hexdigest()
    return _ecdsa.verify(str(r), str(s), hashed, str(Q.x), str(Q.y),
                         curve.name)