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Update to v106r65 release.

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byuu says:

This synchronizes bsnes/higan with many recent internal nall changes.

This will be the last WIP until I am situated in Japan. Apologies for the
bugfixes that didn't get applied yet, I ran out of time.
This commit is contained in:
Tim Allen
2018-10-04 20:11:23 +10:00
parent 336d20123f
commit 03b06257d3
75 changed files with 2242 additions and 1371 deletions
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46
nall/elliptic-curve/curve25519.hpp
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@@ -3,50 +3,52 @@
#if defined(EC_REFERENCE)
#include <nall/elliptic-curve/modulo25519-reference.hpp>
#else
#include <nall/elliptic-curve/modulo25519.hpp>
#include <nall/elliptic-curve/modulo25519-optimized.hpp>
#endif
namespace nall { namespace EllipticCurve {
struct Curve25519 {
auto sharedKey(uint256_t secretKey, uint256_t basepoint = 9) const -> uint256_t {
secretKey &= ((0_u256 - 1) >> 2) - 7;
secretKey |= 1_u256 << 254;
basepoint &= (0_u256 - 1) >> 1;
secretKey &= (1_u256 << 254) - 8;
secretKey |= (1_u256 << 254);
basepoint &= ~0_u256 >> 1;
point p = scalarMultiply(secretKey, modP(basepoint));
return p.x * p.z.reciprocal();
point p = scalarMultiply(basepoint % P, secretKey);
field k = p.x * reciprocal(p.z);
return k();
}
private:
using field = Modulo25519;
struct point { field x, z; };
inline auto montgomeryAdd(point p, point q, field b) const -> point {
return {
(p.x * q.x - p.z * q.z).square(),
(p.x * q.z - p.z * q.x).square() * b
};
}
const BarrettReduction<256> P = BarrettReduction<256>{EllipticCurve::P};
inline auto montgomeryDouble(point p) const -> point {
field a = (p.x + p.z).square();
field b = (p.x - p.z).square();
field a = square(p.x + p.z);
field b = square(p.x - p.z);
field c = a - b;
field d = a + c * 121665;
return {a * b, c * d};
}
inline auto scalarMultiply(uint256_t e, field b) const -> point {
inline auto montgomeryAdd(point p, point q, field b) const -> point {
return {
square(p.x * q.x - p.z * q.z),
square(p.x * q.z - p.z * q.x) * b
};
}
inline auto scalarMultiply(field b, uint256_t exponent) const -> point {
point p{1, 0}, q{b, 1};
for(uint n : reverse(range(255))) {
bool bit = e >> n & 1;
cswap(bit, p.x, q.x);
cswap(bit, p.z, q.z);
for(uint bit : reverse(range(255))) {
bool condition = exponent >> bit & 1;
cswap(condition, p.x, q.x);
cswap(condition, p.z, q.z);
q = montgomeryAdd(p, q, b);
p = montgomeryDouble(p);
cswap(bit, p.x, q.x);
cswap(bit, p.z, q.z);
cswap(condition, p.x, q.x);
cswap(condition, p.z, q.z);
}
return p;
}