/*
- * Written by Adam Langley (Google) for the OpenSSL project
+ * Copyright 2011-2019 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL license (the "License"). You may not use
+ * this file except in compliance with the License. You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
*/
+
/* Copyright 2011 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
typedef uint8_t u8;
typedef uint32_t u32;
typedef uint64_t u64;
-typedef int64_t s64;
/*
* The underlying field. P256 operates over GF(2^256-2^224+2^192+2^96-1). We
*((u64 *)&out[24]) = in[3];
}
-/* To preserve endianness when using BN_bn2bin and BN_bin2bn */
-static void flip_endian(u8 *out, const u8 *in, unsigned len)
-{
- unsigned i;
- for (i = 0; i < len; ++i)
- out[i] = in[len - 1 - i];
-}
-
/* BN_to_felem converts an OpenSSL BIGNUM into an felem */
static int BN_to_felem(felem out, const BIGNUM *bn)
{
- felem_bytearray b_in;
felem_bytearray b_out;
- unsigned num_bytes;
+ int num_bytes;
- /* BN_bn2bin eats leading zeroes */
- memset(b_out, 0, sizeof(b_out));
- num_bytes = BN_num_bytes(bn);
- if (num_bytes > sizeof b_out) {
+ if (BN_is_negative(bn)) {
ECerr(EC_F_BN_TO_FELEM, EC_R_BIGNUM_OUT_OF_RANGE);
return 0;
}
- if (BN_is_negative(bn)) {
+ num_bytes = BN_bn2lebinpad(bn, b_out, sizeof(b_out));
+ if (num_bytes < 0) {
ECerr(EC_F_BN_TO_FELEM, EC_R_BIGNUM_OUT_OF_RANGE);
return 0;
}
- num_bytes = BN_bn2bin(bn, b_in);
- flip_endian(b_out, b_in, num_bytes);
bin32_to_felem(out, b_out);
return 1;
}
/* felem_to_BN converts an felem into an OpenSSL BIGNUM */
static BIGNUM *smallfelem_to_BN(BIGNUM *out, const smallfelem in)
{
- felem_bytearray b_in, b_out;
- smallfelem_to_bin32(b_in, in);
- flip_endian(b_out, b_in, sizeof b_out);
- return BN_bin2bn(b_out, sizeof b_out, out);
+ felem_bytearray b_out;
+ smallfelem_to_bin32(b_out, in);
+ return BN_lebin2bn(b_out, sizeof(b_out), out);
}
/*-
{
felem tmp;
u64 a, b, mask;
- s64 high, low;
+ u64 high, low;
static const u64 kPrime3Test = 0x7fffffff00000001ul; /* 2^63 - 2^32 + 1 */
/* Carry 2->3 */
* In order to make space in tmp[3] for the carry from 2 -> 3, we
* conditionally subtract kPrime if tmp[3] is large enough.
*/
- high = tmp[3] >> 64;
+ high = (u64)(tmp[3] >> 64);
/* As tmp[3] < 2^65, high is either 1 or 0 */
- high <<= 63;
- high >>= 63;
+ high = 0 - high;
/*-
* high is:
* all ones if the high word of tmp[3] is 1
- * all zeros if the high word of tmp[3] if 0 */
- low = tmp[3];
- mask = low >> 63;
+ * all zeros if the high word of tmp[3] if 0
+ */
+ low = (u64)tmp[3];
+ mask = 0 - (low >> 63);
/*-
* mask is:
* all ones if the MSB of low is 1
- * all zeros if the MSB of low if 0 */
+ * all zeros if the MSB of low if 0
+ */
low &= bottom63bits;
low -= kPrime3Test;
/* if low was greater than kPrime3Test then the MSB is zero */
low = ~low;
- low >>= 63;
+ low = 0 - (low >> 63);
/*-
* low is:
* all ones if low was > kPrime3Test
- * all zeros if low was <= kPrime3Test */
+ * all zeros if low was <= kPrime3Test
+ */
mask = (mask & low) | high;
tmp[0] -= mask & kPrime[0];
tmp[1] -= mask & kPrime[1];
equal &= equal << 4;
equal &= equal << 2;
equal &= equal << 1;
- equal = ((s64) equal) >> 63;
+ equal = 0 - (equal >> 63);
all_equal_so_far &= equal;
}
is_zero &= is_zero << 4;
is_zero &= is_zero << 2;
is_zero &= is_zero << 1;
- is_zero = ((s64) is_zero) >> 63;
+ is_zero = 0 - (is_zero >> 63);
is_p = (small[0] ^ kPrime[0]) |
(small[1] ^ kPrime[1]) |
is_p &= is_p << 4;
is_p &= is_p << 2;
is_p &= is_p << 1;
- is_p = ((s64) is_p) >> 63;
+ is_p = 0 - (is_p >> 63);
is_zero |= is_p;
return result;
}
-static int smallfelem_is_zero_int(const smallfelem small)
+static int smallfelem_is_zero_int(const void *small)
{
return (int)(smallfelem_is_zero(small) & ((limb) 1));
}
ec_GFp_nist_field_mul,
ec_GFp_nist_field_sqr,
0 /* field_div */ ,
+ ec_GFp_simple_field_inv,
0 /* field_encode */ ,
0 /* field_decode */ ,
0, /* field_set_to_one */
sizeof(smallfelem),
tmp_smallfelems,
(void (*)(void *))smallfelem_one,
- (int (*)(const void *))
smallfelem_is_zero_int,
(void (*)(void *, const void *))
smallfelem_assign,
felem_bytearray *secrets = NULL;
smallfelem (*pre_comp)[17][3] = NULL;
smallfelem *tmp_smallfelems = NULL;
- felem_bytearray tmp;
- unsigned i, num_bytes;
+ unsigned i;
+ int num_bytes;
int have_pre_comp = 0;
size_t num_points = num;
smallfelem x_in, y_in, z_in;
memset(secrets, 0, sizeof(*secrets) * num_points);
memset(pre_comp, 0, sizeof(*pre_comp) * num_points);
for (i = 0; i < num_points; ++i) {
- if (i == num)
+ if (i == num) {
/*
* we didn't have a valid precomputation, so we pick the
* generator
*/
- {
p = EC_GROUP_get0_generator(group);
p_scalar = scalar;
- } else
+ } else {
/* the i^th point */
- {
p = points[i];
p_scalar = scalars[i];
}
ECerr(EC_F_EC_GFP_NISTP256_POINTS_MUL, ERR_R_BN_LIB);
goto err;
}
- num_bytes = BN_bn2bin(tmp_scalar, tmp);
- } else
- num_bytes = BN_bn2bin(p_scalar, tmp);
- flip_endian(secrets[i], tmp, num_bytes);
+ num_bytes = BN_bn2lebinpad(tmp_scalar,
+ secrets[i], sizeof(secrets[i]));
+ } else {
+ num_bytes = BN_bn2lebinpad(p_scalar,
+ secrets[i], sizeof(secrets[i]));
+ }
+ if (num_bytes < 0) {
+ ECerr(EC_F_EC_GFP_NISTP256_POINTS_MUL, ERR_R_BN_LIB);
+ goto err;
+ }
/* precompute multiples */
if ((!BN_to_felem(x_out, p->X)) ||
(!BN_to_felem(y_out, p->Y)) ||
ECerr(EC_F_EC_GFP_NISTP256_POINTS_MUL, ERR_R_BN_LIB);
goto err;
}
- num_bytes = BN_bn2bin(tmp_scalar, tmp);
- } else
- num_bytes = BN_bn2bin(scalar, tmp);
- flip_endian(g_secret, tmp, num_bytes);
+ num_bytes = BN_bn2lebinpad(tmp_scalar, g_secret, sizeof(g_secret));
+ } else {
+ num_bytes = BN_bn2lebinpad(scalar, g_secret, sizeof(g_secret));
+ }
/* do the multiplication with generator precomputation */
batch_mul(x_out, y_out, z_out,
(const felem_bytearray(*))secrets, num_points,
g_secret,
mixed, (const smallfelem(*)[17][3])pre_comp, g_pre_comp);
- } else
+ } else {
/* do the multiplication without generator precomputation */
batch_mul(x_out, y_out, z_out,
(const felem_bytearray(*))secrets, num_points,
NULL, mixed, (const smallfelem(*)[17][3])pre_comp, NULL);
+ }
/* reduce the output to its unique minimal representation */
felem_contract(x_in, x_out);
felem_contract(y_in, y_out);