mirror of
https://github.com/trezor/trezor-firmware.git
synced 2024-11-24 00:18:26 +00:00
67 lines
2.3 KiB
C
67 lines
2.3 KiB
C
|
/*
|
||
|
|
Public domain by Andrew M. <liquidsun@gmail.com>
|
||
|
|
See: https://github.com/floodyberry/curve25519-donna
|
||
|
|
|
||
|
|
Curve25519 implementation agnostic helpers
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include "ed25519-donna.h"
|
||
|
|
|
||
|
|
/*
|
||
|
|
* In: b = 2^5 - 2^0
|
||
|
|
* Out: b = 2^250 - 2^0
|
||
|
|
*/
|
||
|
|
void curve25519_pow_two5mtwo0_two250mtwo0(bignum25519 b) {
|
||
|
|
bignum25519 ALIGN(16) t0,c;
|
||
|
|
|
||
|
|
/* 2^5 - 2^0 */ /* b */
|
||
|
|
/* 2^10 - 2^5 */ curve25519_square_times(t0, b, 5);
|
||
|
|
/* 2^10 - 2^0 */ curve25519_mul_noinline(b, t0, b);
|
||
|
|
/* 2^20 - 2^10 */ curve25519_square_times(t0, b, 10);
|
||
|
|
/* 2^20 - 2^0 */ curve25519_mul_noinline(c, t0, b);
|
||
|
|
/* 2^40 - 2^20 */ curve25519_square_times(t0, c, 20);
|
||
|
|
/* 2^40 - 2^0 */ curve25519_mul_noinline(t0, t0, c);
|
||
|
|
/* 2^50 - 2^10 */ curve25519_square_times(t0, t0, 10);
|
||
|
|
/* 2^50 - 2^0 */ curve25519_mul_noinline(b, t0, b);
|
||
|
|
/* 2^100 - 2^50 */ curve25519_square_times(t0, b, 50);
|
||
|
|
/* 2^100 - 2^0 */ curve25519_mul_noinline(c, t0, b);
|
||
|
|
/* 2^200 - 2^100 */ curve25519_square_times(t0, c, 100);
|
||
|
|
/* 2^200 - 2^0 */ curve25519_mul_noinline(t0, t0, c);
|
||
|
|
/* 2^250 - 2^50 */ curve25519_square_times(t0, t0, 50);
|
||
|
|
/* 2^250 - 2^0 */ curve25519_mul_noinline(b, t0, b);
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* z^(p - 2) = z(2^255 - 21)
|
||
|
|
*/
|
||
|
|
void curve25519_recip(bignum25519 out, const bignum25519 z) {
|
||
|
|
bignum25519 ALIGN(16) a,t0,b;
|
||
|
|
|
||
|
|
/* 2 */ curve25519_square_times(a, z, 1); /* a = 2 */
|
||
|
|
/* 8 */ curve25519_square_times(t0, a, 2);
|
||
|
|
/* 9 */ curve25519_mul_noinline(b, t0, z); /* b = 9 */
|
||
|
|
/* 11 */ curve25519_mul_noinline(a, b, a); /* a = 11 */
|
||
|
|
/* 22 */ curve25519_square_times(t0, a, 1);
|
||
|
|
/* 2^5 - 2^0 = 31 */ curve25519_mul_noinline(b, t0, b);
|
||
|
|
/* 2^250 - 2^0 */ curve25519_pow_two5mtwo0_two250mtwo0(b);
|
||
|
|
/* 2^255 - 2^5 */ curve25519_square_times(b, b, 5);
|
||
|
|
/* 2^255 - 21 */ curve25519_mul_noinline(out, b, a);
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* z^((p-5)/8) = z^(2^252 - 3)
|
||
|
|
*/
|
||
|
|
void curve25519_pow_two252m3(bignum25519 two252m3, const bignum25519 z) {
|
||
|
|
bignum25519 ALIGN(16) b,c,t0;
|
||
|
|
|
||
|
|
/* 2 */ curve25519_square_times(c, z, 1); /* c = 2 */
|
||
|
|
/* 8 */ curve25519_square_times(t0, c, 2); /* t0 = 8 */
|
||
|
|
/* 9 */ curve25519_mul_noinline(b, t0, z); /* b = 9 */
|
||
|
|
/* 11 */ curve25519_mul_noinline(c, b, c); /* c = 11 */
|
||
|
|
/* 22 */ curve25519_square_times(t0, c, 1);
|
||
|
|
/* 2^5 - 2^0 = 31 */ curve25519_mul_noinline(b, t0, b);
|
||
|
|
/* 2^250 - 2^0 */ curve25519_pow_two5mtwo0_two250mtwo0(b);
|
||
|
|
/* 2^252 - 2^2 */ curve25519_square_times(b, b, 2);
|
||
|
|
/* 2^252 - 3 */ curve25519_mul_noinline(two252m3, b, z);
|
||
|
|
}
|