/************************************************* * GMP IF Engine Source File * * (C) 1999-2007 Jack Lloyd * *************************************************/ #include #include #include namespace Botan { #if defined(BOTAN_HAS_IF_PUBLIC_KEY_FAMILY) namespace { /************************************************* * GMP IF Operation * *************************************************/ class GMP_IF_Op : public IF_Operation { public: BigInt public_op(const BigInt&) const; BigInt private_op(const BigInt&) const; IF_Operation* clone() const { return new GMP_IF_Op(*this); } GMP_IF_Op(const BigInt& e_bn, const BigInt& n_bn, const BigInt&, const BigInt& p_bn, const BigInt& q_bn, const BigInt& d1_bn, const BigInt& d2_bn, const BigInt& c_bn) : e(e_bn), n(n_bn), p(p_bn), q(q_bn), d1(d1_bn), d2(d2_bn), c(c_bn) {} private: const GMP_MPZ e, n, p, q, d1, d2, c; }; /************************************************* * GMP IF Public Operation * *************************************************/ BigInt GMP_IF_Op::public_op(const BigInt& i_bn) const { GMP_MPZ i(i_bn); mpz_powm(i.value, i.value, e.value, n.value); return i.to_bigint(); } /************************************************* * GMP IF Private Operation * *************************************************/ BigInt GMP_IF_Op::private_op(const BigInt& i_bn) const { if(mpz_cmp_ui(p.value, 0) == 0) throw Internal_Error("GMP_IF_Op::private_op: No private key"); GMP_MPZ j1, j2, h(i_bn); mpz_powm(j1.value, h.value, d1.value, p.value); mpz_powm(j2.value, h.value, d2.value, q.value); mpz_sub(h.value, j1.value, j2.value); mpz_mul(h.value, h.value, c.value); mpz_mod(h.value, h.value, p.value); mpz_mul(h.value, h.value, q.value); mpz_add(h.value, h.value, j2.value); return h.to_bigint(); } } /************************************************* * Acquire an IF op * *************************************************/ IF_Operation* GMP_Engine::if_op(const BigInt& e, const BigInt& n, const BigInt& d, const BigInt& p, const BigInt& q, const BigInt& d1, const BigInt& d2, const BigInt& c) const { return new GMP_IF_Op(e, n, d, p, q, d1, d2, c); } #endif }