bsnes-libretro/nall/mac/poly1305.hpp
Tim Allen f3e67da937 Update to v101r19 release.
byuu says:

Changelog:

-   added \~130 new PAL games to icarus (courtesy of Smarthuman
    and aquaman)
-   added all three Korean-localized games to icarus
-   sfc: removed SuperDisc emulation (it was going nowhere)
-   sfc: fixed MSU1 regression where the play/repeat flags were not
    being cleared on track select
-   nall: cryptography support added; will be used to sign future
    databases (validation will always be optional)
-   minor shims to fix compilation issues due to nall changes

The real magic is that we now have 25-30% of the PAL SNES library in
icarus!

Signing will be tricky. Obviously if I put the public key inside the
higan archive, then all anyone has to do is change that public key for
their own releases. And if you download from my site (which is now over
HTTPS), then you don't need the signing to verify integrity. I may just
put the public key on my site on my site and leave it at that, we'll
see.
2016-10-28 08:16:58 +11:00

117 lines
3.2 KiB
C++

#pragma once
#include <nall/arithmetic.hpp>
namespace nall { namespace MAC {
struct Poly1305 {
auto initialize(uint256_t key) -> void {
uint64_t t0 = key >> 0;
uint64_t t1 = key >> 64;
pad[0] = key >> 128;
pad[1] = key >> 192;
r[0] = (t0 ) & 0xffc0fffffff;
r[1] = (t0 >> 44 | t1 << 20) & 0xfffffc0ffff;
r[2] = ( t1 >> 24) & 0x00ffffffc0f;
h[0] = 0, h[1] = 0, h[2] = 0;
offset = 0;
}
auto process(const uint8_t* data, uint64_t size) -> void {
while(size--) {
buffer[offset++] = *data++;
if(offset >= 16) {
block();
offset = 0;
}
}
}
auto finish() -> uint128_t {
if(offset) {
buffer[offset++] = 1;
while(offset < 16) buffer[offset++] = 0;
block(true);
}
uint64_t h0 = h[0], h1 = h[1], h2 = h[2];
uint64_t c = h1 >> 44; h1 &= 0xfffffffffff;
h2 += c; c = h2 >> 42; h2 &= 0x3ffffffffff;
h0 += c * 5; c = h0 >> 44; h0 &= 0xfffffffffff;
h1 += c; c = h1 >> 44; h1 &= 0xfffffffffff;
h2 += c; c = h2 >> 42; h2 &= 0x3ffffffffff;
h0 += c * 5; c = h0 >> 44; h0 &= 0xfffffffffff;
h1 += c;
uint64_t g0 = h0 + 5; c = g0 >> 44; g0 &= 0xfffffffffff;
uint64_t g1 = h1 + c; c = g1 >> 44; g1 &= 0xfffffffffff;
uint64_t g2 = h2 + c - (1ull << 42);
c = (g2 >> 63) - 1;
g0 &= c, g1 &= c, g2 &= c;
c = ~c;
h0 = (h0 & c) | g0;
h1 = (h1 & c) | g1;
h2 = (h2 & c) | g2;
uint64_t t0 = pad[0], t1 = pad[1];
h0 += ((t0 ) & 0xfffffffffff) ; c = h0 >> 44; h0 &= 0xfffffffffff;
h1 += ((t0 >> 44 | t1 << 20) & 0xfffffffffff) + c; c = h1 >> 44; h1 &= 0xfffffffffff;
h2 += (( t1 >> 24) & 0x3ffffffffff) + c; h2 &= 0x3ffffffffff;
h0 = (h0 >> 0 | h1 << 44);
h1 = (h1 >> 20 | h2 << 24);
r[0] = 0, r[1] = 0, r[2] = 0;
h[0] = 0, h[1] = 0, h[2] = 0;
pad[0] = 0, pad[1] = 0;
memory::fill(buffer, 16);
offset = 0;
return uint128_t(h1) << 64 | h0;
}
private:
auto block(bool last = false) -> void {
uint64_t r0 = r[0], r1 = r[1], r2 = r[2];
uint64_t h0 = h[0], h1 = h[1], h2 = h[2];
uint64_t s1 = r1 * 20;
uint64_t s2 = r2 * 20;
uint64_t t0 = memory::readl<8>(buffer + 0);
uint64_t t1 = memory::readl<8>(buffer + 8);
h0 += ((t0 ) & 0xfffffffffff);
h1 += ((t0 >> 44 | t1 << 20) & 0xfffffffffff);
h2 += (( t1 >> 24) & 0x3ffffffffff) | (last ? 0 : 1ull << 40);
uint128_t d, d0, d1, d2;
d0 = (uint128_t)h0 * r0; d = (uint128_t)h1 * s2; d0 += d; d = (uint128_t)h2 * s1; d0 += d;
d1 = (uint128_t)h0 * r1; d = (uint128_t)h1 * r0; d1 += d; d = (uint128_t)h2 * s2; d1 += d;
d2 = (uint128_t)h0 * r2; d = (uint128_t)h1 * r1; d2 += d; d = (uint128_t)h2 * r0; d2 += d;
uint64_t c = (uint64_t)(d0 >> 44); h0 = (uint64_t)d0 & 0xfffffffffff;
d1 += c; c = (uint64_t)(d1 >> 44); h1 = (uint64_t)d1 & 0xfffffffffff;
d2 += c; c = (uint64_t)(d2 >> 42); h2 = (uint64_t)d2 & 0x3ffffffffff;
h0 += c * 5; c = h0 >> 44; h0 &= 0xfffffffffff;
h1 += c;
h[0] = h0, h[1] = h1, h[2] = h2;
}
uint64_t r[3];
uint64_t h[3];
uint64_t pad[2];
uint8_t buffer[16];
uint offset;
};
}}