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-rw-r--r--libssh/src/fe25519.c416
1 files changed, 0 insertions, 416 deletions
diff --git a/libssh/src/fe25519.c b/libssh/src/fe25519.c
deleted file mode 100644
index 0cedd89d..00000000
--- a/libssh/src/fe25519.c
+++ /dev/null
@@ -1,416 +0,0 @@
-/*
- * Public Domain, Authors: Daniel J. Bernstein, Niels Duif, Tanja Lange,
- * Peter Schwabe, Bo-Yin Yang.
- * Copied from supercop-20130419/crypto_sign/ed25519/ref/fe25519.c
- */
-
-#define WINDOWSIZE 1 /* Should be 1,2, or 4 */
-#define WINDOWMASK ((1<<WINDOWSIZE)-1)
-
-#include "libssh/fe25519.h"
-
-static uint32_t equal(uint32_t a,uint32_t b) /* 16-bit inputs */
-{
- uint32_t x = a ^ b; /* 0: yes; 1..65535: no */
- x -= 1; /* 4294967295: yes; 0..65534: no */
- x >>= 31; /* 1: yes; 0: no */
- return x;
-}
-
-static uint32_t ge(uint32_t a,uint32_t b) /* 16-bit inputs */
-{
- unsigned int x = a;
-
- x -= (unsigned int) b; /* 0..65535: yes; 4294901761..4294967295: no */
- x >>= 31; /* 0: yes; 1: no */
- x ^= 1; /* 1: yes; 0: no */
-
- return x;
-}
-
-static uint32_t times19(uint32_t a)
-{
- return (a << 4) + (a << 1) + a;
-}
-
-static uint32_t times38(uint32_t a)
-{
- return (a << 5) + (a << 2) + (a << 1);
-}
-
-static void reduce_add_sub(fe25519 *r)
-{
- uint32_t t;
- int i,rep;
-
- for(rep = 0; rep < 4; rep++) {
- t = r->v[31] >> 7;
- r->v[31] &= 127;
- t = times19(t);
- r->v[0] += t;
- for(i = 0; i < 31; i++) {
- t = r->v[i] >> 8;
- r->v[i+1] += t;
- r->v[i] &= 255;
- }
- }
-}
-
-static void reduce_mul(fe25519 *r)
-{
- uint32_t t;
- int i,rep;
-
- for(rep = 0; rep < 2; rep++) {
- t = r->v[31] >> 7;
- r->v[31] &= 127;
- t = times19(t);
- r->v[0] += t;
- for(i = 0; i < 31; i++) {
- t = r->v[i] >> 8;
- r->v[i+1] += t;
- r->v[i] &= 255;
- }
- }
-}
-
-/* reduction modulo 2^255-19 */
-void fe25519_freeze(fe25519 *r)
-{
- int i;
- uint32_t m = equal(r->v[31],127);
-
- for (i = 30; i > 0; i--) {
- m &= equal(r->v[i],255);
- }
- m &= ge(r->v[0],237);
-
- m = -m;
-
- r->v[31] -= m&127;
- for (i = 30; i > 0; i--) {
- r->v[i] -= m&255;
- }
- r->v[0] -= m&237;
-}
-
-void fe25519_unpack(fe25519 *r, const unsigned char x[32])
-{
- int i;
-
- for (i = 0;i < 32; i++) {
- r->v[i] = x[i];
- }
-
- r->v[31] &= 127;
-}
-
-/* Assumes input x being reduced below 2^255 */
-void fe25519_pack(unsigned char r[32], const fe25519 *x)
-{
- int i;
-
- fe25519 y = *x;
- fe25519_freeze(&y);
-
- for (i = 0; i < 32; i++) {
- r[i] = y.v[i];
- }
-}
-
-int fe25519_iszero(const fe25519 *x)
-{
- int i;
- int r;
-
- fe25519 t = *x;
- fe25519_freeze(&t);
-
- r = equal(t.v[0],0);
- for (i = 1; i < 32; i++) {
- r &= equal(t.v[i],0);
- }
-
- return r;
-}
-
-int fe25519_iseq_vartime(const fe25519 *x, const fe25519 *y)
-{
- int i;
-
- fe25519 t1 = *x;
- fe25519 t2 = *y;
- fe25519_freeze(&t1);
- fe25519_freeze(&t2);
-
- for (i = 0; i < 32; i++) {
- if(t1.v[i] != t2.v[i]) {
- return 0;
- }
- }
-
- return 1;
-}
-
-void fe25519_cmov(fe25519 *r, const fe25519 *x, unsigned char b)
-{
- int i;
- uint32_t mask = b;
-
- mask = -mask;
-
- for (i = 0; i < 32; i++) {
- r->v[i] ^= mask & (x->v[i] ^ r->v[i]);
- }
-}
-
-unsigned char fe25519_getparity(const fe25519 *x)
-{
- fe25519 t = *x;
- fe25519_freeze(&t);
-
- return t.v[0] & 1;
-}
-
-void fe25519_setone(fe25519 *r)
-{
- int i;
-
- r->v[0] = 1;
- for (i = 1; i < 32; i++) {
- r->v[i]=0;
- }
-}
-
-void fe25519_setzero(fe25519 *r)
-{
- int i;
-
- for (i = 0; i < 32; i++) {
- r->v[i]=0;
- }
-}
-
-void fe25519_neg(fe25519 *r, const fe25519 *x)
-{
- fe25519 t;
- int i;
-
- for (i = 0; i < 32; i++) {
- t.v[i]=x->v[i];
- }
-
- fe25519_setzero(r);
- fe25519_sub(r, r, &t);
-}
-
-void fe25519_add(fe25519 *r, const fe25519 *x, const fe25519 *y)
-{
- int i;
-
- for (i = 0; i < 32; i++) {
- r->v[i] = x->v[i] + y->v[i];
- }
-
- reduce_add_sub(r);
-}
-
-void fe25519_sub(fe25519 *r, const fe25519 *x, const fe25519 *y)
-{
- int i;
- uint32_t t[32];
-
- t[0] = x->v[0] + 0x1da;
- t[31] = x->v[31] + 0xfe;
-
- for (i = 1; i < 31; i++) {
- t[i] = x->v[i] + 0x1fe;
- }
-
- for (i = 0; i < 32; i++) {
- r->v[i] = t[i] - y->v[i];
- }
-
- reduce_add_sub(r);
-}
-
-void fe25519_mul(fe25519 *r, const fe25519 *x, const fe25519 *y)
-{
- int i,j;
- uint32_t t[63];
-
- for (i = 0; i < 63; i++) {
- t[i] = 0;
- }
-
- for (i = 0; i < 32; i++) {
- for (j = 0; j < 32; j++) {
- t[i+j] += x->v[i] * y->v[j];
- }
- }
-
- for (i = 32; i < 63; i++) {
- r->v[i-32] = t[i-32] + times38(t[i]);
- }
- r->v[31] = t[31]; /* result now in r[0]...r[31] */
-
- reduce_mul(r);
-}
-
-void fe25519_square(fe25519 *r, const fe25519 *x)
-{
- fe25519_mul(r, x, x);
-}
-
-void fe25519_invert(fe25519 *r, const fe25519 *x)
-{
- fe25519 z2;
- fe25519 z9;
- fe25519 z11;
- fe25519 z2_5_0;
- fe25519 z2_10_0;
- fe25519 z2_20_0;
- fe25519 z2_50_0;
- fe25519 z2_100_0;
- fe25519 t0;
- fe25519 t1;
- int i;
-
- /* 2 */ fe25519_square(&z2, x);
- /* 4 */ fe25519_square(&t1, &z2);
- /* 8 */ fe25519_square(&t0, &t1);
- /* 9 */ fe25519_mul(&z9, &t0, x);
- /* 11 */ fe25519_mul(&z11, &z9, &z2);
- /* 22 */ fe25519_square(&t0, &z11);
- /* 2^5 - 2^0 = 31 */ fe25519_mul(&z2_5_0, &t0, &z9);
-
- /* 2^6 - 2^1 */ fe25519_square(&t0, &z2_5_0);
- /* 2^7 - 2^2 */ fe25519_square(&t1, &t0);
- /* 2^8 - 2^3 */ fe25519_square(&t0, &t1);
- /* 2^9 - 2^4 */ fe25519_square(&t1, &t0);
- /* 2^10 - 2^5 */ fe25519_square(&t0, &t1);
- /* 2^10 - 2^0 */ fe25519_mul(&z2_10_0, &t0, &z2_5_0);
-
- /* 2^11 - 2^1 */ fe25519_square(&t0, &z2_10_0);
- /* 2^12 - 2^2 */ fe25519_square(&t1, &t0);
- /* 2^20 - 2^10 */ for (i = 2;i < 10;i += 2) {
- fe25519_square(&t0, &t1);
- fe25519_square(&t1, &t0);
- }
- /* 2^20 - 2^0 */ fe25519_mul(&z2_20_0, &t1, &z2_10_0);
-
- /* 2^21 - 2^1 */ fe25519_square(&t0, &z2_20_0);
- /* 2^22 - 2^2 */ fe25519_square(&t1, &t0);
- /* 2^40 - 2^20 */ for (i = 2;i < 20;i += 2) {
- fe25519_square(&t0, &t1);
- fe25519_square(&t1,&t0);
- }
- /* 2^40 - 2^0 */ fe25519_mul(&t0, &t1, &z2_20_0);
-
- /* 2^41 - 2^1 */ fe25519_square(&t1, &t0);
- /* 2^42 - 2^2 */ fe25519_square(&t0, &t1);
- /* 2^50 - 2^10 */ for (i = 2; i < 10;i += 2) {
- fe25519_square(&t1, &t0);
- fe25519_square(&t0, &t1);
- }
- /* 2^50 - 2^0 */ fe25519_mul(&z2_50_0,&t0,&z2_10_0);
-
- /* 2^51 - 2^1 */ fe25519_square(&t0, &z2_50_0);
- /* 2^52 - 2^2 */ fe25519_square(&t1, &t0);
- /* 2^100 - 2^50 */ for (i = 2; i < 50; i += 2) {
- fe25519_square(&t0, &t1);
- fe25519_square(&t1,&t0);
- }
- /* 2^100 - 2^0 */ fe25519_mul(&z2_100_0, &t1, &z2_50_0);
-
- /* 2^101 - 2^1 */ fe25519_square(&t1, &z2_100_0);
- /* 2^102 - 2^2 */ fe25519_square(&t0, &t1);
- /* 2^200 - 2^100 */ for (i = 2; i < 100; i += 2) {
- fe25519_square(&t1, &t0);
- fe25519_square(&t0,&t1);
- }
- /* 2^200 - 2^0 */ fe25519_mul(&t1, &t0, &z2_100_0);
-
- /* 2^201 - 2^1 */ fe25519_square(&t0, &t1);
- /* 2^202 - 2^2 */ fe25519_square(&t1, &t0);
- /* 2^250 - 2^50 */ for (i = 2;i < 50;i += 2) {
- fe25519_square(&t0, &t1);
- fe25519_square(&t1,&t0);
- }
- /* 2^250 - 2^0 */ fe25519_mul(&t0, &t1, &z2_50_0);
-
- /* 2^251 - 2^1 */ fe25519_square(&t1, &t0);
- /* 2^252 - 2^2 */ fe25519_square(&t0, &t1);
- /* 2^253 - 2^3 */ fe25519_square(&t1, &t0);
- /* 2^254 - 2^4 */ fe25519_square(&t0, &t1);
- /* 2^255 - 2^5 */ fe25519_square(&t1, &t0);
- /* 2^255 - 21 */ fe25519_mul(r, &t1, &z11);
-}
-
-void fe25519_pow2523(fe25519 *r, const fe25519 *x)
-{
- fe25519 z2;
- fe25519 z9;
- fe25519 z11;
- fe25519 z2_5_0;
- fe25519 z2_10_0;
- fe25519 z2_20_0;
- fe25519 z2_50_0;
- fe25519 z2_100_0;
- fe25519 t;
- int i;
-
- /* 2 */ fe25519_square(&z2, x);
- /* 4 */ fe25519_square(&t, &z2);
- /* 8 */ fe25519_square(&t, &t);
- /* 9 */ fe25519_mul(&z9, &t, x);
- /* 11 */ fe25519_mul(&z11, &z9, &z2);
- /* 22 */ fe25519_square(&t, &z11);
- /* 2^5 - 2^0 = 31 */ fe25519_mul(&z2_5_0, &t, &z9);
-
- /* 2^6 - 2^1 */ fe25519_square(&t, &z2_5_0);
- /* 2^10 - 2^5 */ for (i = 1; i < 5; i++) {
- fe25519_square(&t,&t);
- }
- /* 2^10 - 2^0 */ fe25519_mul(&z2_10_0, &t, &z2_5_0);
-
- /* 2^11 - 2^1 */ fe25519_square(&t, &z2_10_0);
- /* 2^20 - 2^10 */ for (i = 1; i < 10; i++) {
- fe25519_square(&t, &t);
- }
- /* 2^20 - 2^0 */ fe25519_mul(&z2_20_0, &t, &z2_10_0);
-
- /* 2^21 - 2^1 */ fe25519_square(&t, &z2_20_0);
- /* 2^40 - 2^20 */ for (i = 1; i < 20; i++) {
- fe25519_square(&t,&t);
- }
- /* 2^40 - 2^0 */ fe25519_mul(&t, &t, &z2_20_0);
-
- /* 2^41 - 2^1 */ fe25519_square(&t, &t);
- /* 2^50 - 2^10 */ for (i = 1; i < 10; i++) {
- fe25519_square(&t,&t);
- }
- /* 2^50 - 2^0 */ fe25519_mul(&z2_50_0, &t, &z2_10_0);
-
- /* 2^51 - 2^1 */ fe25519_square(&t, &z2_50_0);
- /* 2^100 - 2^50 */ for (i = 1; i < 50; i++) {
- fe25519_square(&t, &t);
- }
- /* 2^100 - 2^0 */ fe25519_mul(&z2_100_0, &t, &z2_50_0);
-
- /* 2^101 - 2^1 */ fe25519_square(&t, &z2_100_0);
- /* 2^200 - 2^100 */ for (i = 1; i < 100; i++) {
- fe25519_square(&t, &t);
- }
- /* 2^200 - 2^0 */ fe25519_mul(&t, &t, &z2_100_0);
-
- /* 2^201 - 2^1 */ fe25519_square(&t, &t);
- /* 2^250 - 2^50 */ for (i = 1; i < 50; i++) {
- fe25519_square(&t, &t);
- }
- /* 2^250 - 2^0 */ fe25519_mul(&t, &t, &z2_50_0);
-
- /* 2^251 - 2^1 */ fe25519_square(&t, &t);
- /* 2^252 - 2^2 */ fe25519_square(&t, &t);
- /* 2^252 - 3 */ fe25519_mul(r, &t, x);
-}
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