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Diffstat (limited to 'src/pk/ecdsa/curve_gfp.h')
| -rw-r--r-- | src/pk/ecdsa/curve_gfp.h | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/src/pk/ecdsa/curve_gfp.h b/src/pk/ecdsa/curve_gfp.h new file mode 100644 index 000000000..49688b5dc --- /dev/null +++ b/src/pk/ecdsa/curve_gfp.h @@ -0,0 +1,165 @@ +/****************************************************** + * Elliptic curves over GF(p) (header file) * + * * + * (C) 2007 Martin Doering * + * [email protected] * + * Christoph Ludwig * + * [email protected] * + * Falko Strenzke * + * [email protected] * + ******************************************************/ + +#ifndef BOTAN_EC_CURVE_GFP_H__ +#define BOTAN_EC_CURVE_GFP_H__ + +#include <botan/gfp_element.h> +#include <botan/bigint.h> +#include <tr1/memory> + +namespace Botan { + +/** +* This class represents an elliptic curve over GF(p) +*/ +class CurveGFp + { + public: + /** + * Construct the elliptic curve E: y^2 = x^3 + ax + b over GF(p) + * @param a first coefficient + * @param b second coefficient + * @param p prime number of the field + */ + CurveGFp(GFpElement const& a, GFpElement const& b, + const BigInt& p); + + /** + * Copy constructor + * @param other The curve to clone + */ + CurveGFp(CurveGFp const& other); + + /** + * Assignment operator + * @param other The curve to use as source for the assignment + */ + CurveGFp const& operator=(CurveGFp const& other); + + /** + * Set the shared GFpModulus object. + * Warning: do not use this function unless you know in detail how + * the sharing of values + * in the various EC related objects works. + * Do NOT spread pointers to a GFpModulus over different threads! + * @param mod a shared pointer to a GFpModulus object suitable for + * *this. + */ + void set_shrd_mod(std::tr1::shared_ptr<Botan::GFpModulus> const mod); + + // getters + + /** + * Get coefficient a + * @result coefficient a + */ + GFpElement const get_a() const; + + /** + * Get coefficient b + * @result coefficient b + */ + GFpElement const get_b() const; + + /** + * Get the GFpElement coefficient a transformed + * to its m-residue. This can be used for efficency reasons: the curve + * stores the transformed version after the first invocation of this + * function. + * @result the coefficient a, transformed to its m-residue + */ + GFpElement const get_mres_a() const; + + /** + * Get the GFpElement coefficient b transformed + * to it´s m-residue. This can be used for efficency reasons: the curve + * stores the transformed version after the first invocation of this + * function. + * @result the coefficient b, transformed to it´s m-residue + */ + GFpElement const get_mres_b() const; + + + /** + * Get the GFpElement 1 transformed + * to it´s m-residue. This can be used for efficency reasons: the curve + * stores the transformed version after the first invocation of this + * function. + * @result the GFpElement 1, transformed to it´s m-residue + */ + std::tr1::shared_ptr<GFpElement const> const get_mres_one() const; + + /** + * Get prime modulus of the field of the curve + * @result prime modulus of the field of the curve + */ + BigInt const get_p() const; + /*inline std::tr1::shared_ptr<BigInt> const get_ptr_p() const + { + return mp_p; + }*/ + + /** + * Retrieve a shared pointer to the curves GFpModulus object for efficient storage + * and computation of montgomery multiplication related data members and functions. + * Warning: do not use this function unless you know in detail how the sharing of values + * in the various EC related objects works. + * Do NOT spread pointers to a GFpModulus over different threads! + * @result a shared pointer to a GFpModulus object + */ + inline std::tr1::shared_ptr<Botan::GFpModulus> const get_ptr_mod() const + { + return mp_mod; + } + + /** + * swaps the states of *this and other, does not throw + * @param other The curve to swap values with + */ + void swap(CurveGFp& other); + + private: + std::tr1::shared_ptr<Botan::GFpModulus> mp_mod; + GFpElement mA; + GFpElement mB; + mutable std::tr1::shared_ptr<GFpElement> mp_mres_a; + mutable std::tr1::shared_ptr<GFpElement> mp_mres_b; + mutable std::tr1::shared_ptr<GFpElement> mp_mres_one; + }; + +// relational operators +bool operator==(CurveGFp const& lhs, CurveGFp const& rhs); +inline bool operator!=(CurveGFp const& lhs, CurveGFp const& rhs) { +return !operator==(lhs, rhs); +} + +// swaps the states of curve1 and curve2, does not throw! +// cf. Meyers, Item 25 +inline +void swap(CurveGFp& curve1, CurveGFp& curve2) { +curve1.swap(curve2); +} + +} + +namespace std { + +template<> inline void swap<Botan::CurveGFp>( + Botan::CurveGFp& curve1, + Botan::CurveGFp& curve2) + { + curve1.swap(curve2); + } + +} + +#endif |