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| author | MITSUNARI Shigeo <herumi@nifty.com> | 2016-05-02 15:12:22 +0800 |
|---|---|---|
| committer | MITSUNARI Shigeo <herumi@nifty.com> | 2016-05-02 15:12:25 +0800 |
| commit | ed1b93a738dc9bc88baaa79020578c0f2201b624 (patch) | |
| tree | 0606562cfb308cae81101af67d10551bd3c859a6 /include | |
| parent | e04f97b557d50b02b0a491614a7a6ab12e54b308 (diff) | |
| download | tangerine-mcl-ed1b93a738dc9bc88baaa79020578c0f2201b624.tar.gz tangerine-mcl-ed1b93a738dc9bc88baaa79020578c0f2201b624.tar.zst tangerine-mcl-ed1b93a738dc9bc88baaa79020578c0f2201b624.zip | |
use Frobenius in finalExp
Diffstat (limited to 'include')
| -rw-r--r-- | include/mcl/bn.hpp | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/include/mcl/bn.hpp b/include/mcl/bn.hpp index 775da22..e040e2c 100644 --- a/include/mcl/bn.hpp +++ b/include/mcl/bn.hpp @@ -401,6 +401,8 @@ struct BNT { /* y = x^((p^12 - 1) / r) (p^12 - 1) / r = (p^2 + 1) (p^6 - 1) (p^4 - p^2 + 1)/r + (a + bw)^(p^6) = a - bw in Fp12 + (p^4 - p^2 + 1)/r = c0 + c1 p + c2 p^2 + p^3 */ static void finalExp(Fp12& y, const Fp12& x) { @@ -413,14 +415,26 @@ struct BNT { Fp12::inv(rv, z); Fp6::neg(z.b, z.b); // z^(p^6) = conjugate of z Fp12::mul(y, z, rv); + + mpz_class c0 = -2 + param.z * (-18 + param.z * (-30 - 36 *param.z)); + mpz_class c1 = 1 + param.z * (-12 + param.z * (-18 - 36 * param.z)); + mpz_class c2 = 6 * param.z * param.z + 1; + Fp12 t0, t1, t2, t3; + Fp12::power(t0, y, c0); + Frobenius(t1, y); + Frobenius(t2, t1); + Frobenius(t3, t2); + Fp12::power(t1, t1, c1); + Fp12::power(t2, t2, c2); + y = t0 * t1 * t2 * t3; #else - Fp12::power(y, x, p2 + 1); - Fp12::power(y, y, p4 * p2 - 1); -#endif const mpz_class& p = param.p; mpz_class p2 = p * p; mpz_class p4 = p2 * p2; + Fp12::power(y, x, p2 + 1); + Fp12::power(y, y, p4 * p2 - 1); Fp12::power(y, y, (p4 - p2 + 1) / param.r); +#endif } static void optimalAtePairing(Fp12& f, const G2& Q, const G1& P) { |