| 摘要 |
<p>A method for transforming data with a secret parameter in an elliptic curve cryptosystem based on an elliptic curve defined over an underlying prime field, the method comprising multiplying a point of the elliptic curve, representing the data to be transformed, by a scalar representing the secret parameter, wherein the multiplying includes performing at least one point addition operation and at least one point doubling operation on points of the elliptic curve. The method includes: providing a representation in affine coordinates of the elliptic curve point to be multiplied, and a representation in projective coordinates of intermediate elliptic curve points obtained during said multiplying; performing both the point addition operation and the point doubling operation by means of a sequence of elementary prime field operation types, the elementary prime field operation types including: a first type of prime field operations including field multiplication and field squaring of coordinates of the elliptic curve points, and a second type of prime field operations including field addition, field doubling, and field subtraction of coordinates of the elliptic curve points. A device is also provided, for transforming data with a secret parameter, comprising an integrated circuit adapted to perform the above mentioned method.</p> |
