e0ceeab0d1
- Use defined constants instead of hard-coding their integer value. - Allocate secp256k1 structs on the C stack instead of converting []byte - Remove dead code
100 lines
3.1 KiB
C
100 lines
3.1 KiB
C
/**********************************************************************
|
|
* Copyright (c) 2013, 2014 Pieter Wuille *
|
|
* Distributed under the MIT software license, see the accompanying *
|
|
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
|
|
**********************************************************************/
|
|
|
|
#ifndef _SECP256K1_ECKEY_IMPL_H_
|
|
#define _SECP256K1_ECKEY_IMPL_H_
|
|
|
|
#include "eckey.h"
|
|
|
|
#include "scalar.h"
|
|
#include "field.h"
|
|
#include "group.h"
|
|
#include "ecmult_gen.h"
|
|
|
|
static int secp256k1_eckey_pubkey_parse(secp256k1_ge *elem, const unsigned char *pub, size_t size) {
|
|
if (size == 33 && (pub[0] == 0x02 || pub[0] == 0x03)) {
|
|
secp256k1_fe x;
|
|
return secp256k1_fe_set_b32(&x, pub+1) && secp256k1_ge_set_xo_var(elem, &x, pub[0] == 0x03);
|
|
} else if (size == 65 && (pub[0] == 0x04 || pub[0] == 0x06 || pub[0] == 0x07)) {
|
|
secp256k1_fe x, y;
|
|
if (!secp256k1_fe_set_b32(&x, pub+1) || !secp256k1_fe_set_b32(&y, pub+33)) {
|
|
return 0;
|
|
}
|
|
secp256k1_ge_set_xy(elem, &x, &y);
|
|
if ((pub[0] == 0x06 || pub[0] == 0x07) && secp256k1_fe_is_odd(&y) != (pub[0] == 0x07)) {
|
|
return 0;
|
|
}
|
|
return secp256k1_ge_is_valid_var(elem);
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
static int secp256k1_eckey_pubkey_serialize(secp256k1_ge *elem, unsigned char *pub, size_t *size, int compressed) {
|
|
if (secp256k1_ge_is_infinity(elem)) {
|
|
return 0;
|
|
}
|
|
secp256k1_fe_normalize_var(&elem->x);
|
|
secp256k1_fe_normalize_var(&elem->y);
|
|
secp256k1_fe_get_b32(&pub[1], &elem->x);
|
|
if (compressed) {
|
|
*size = 33;
|
|
pub[0] = 0x02 | (secp256k1_fe_is_odd(&elem->y) ? 0x01 : 0x00);
|
|
} else {
|
|
*size = 65;
|
|
pub[0] = 0x04;
|
|
secp256k1_fe_get_b32(&pub[33], &elem->y);
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
static int secp256k1_eckey_privkey_tweak_add(secp256k1_scalar *key, const secp256k1_scalar *tweak) {
|
|
secp256k1_scalar_add(key, key, tweak);
|
|
if (secp256k1_scalar_is_zero(key)) {
|
|
return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
static int secp256k1_eckey_pubkey_tweak_add(const secp256k1_ecmult_context *ctx, secp256k1_ge *key, const secp256k1_scalar *tweak) {
|
|
secp256k1_gej pt;
|
|
secp256k1_scalar one;
|
|
secp256k1_gej_set_ge(&pt, key);
|
|
secp256k1_scalar_set_int(&one, 1);
|
|
secp256k1_ecmult(ctx, &pt, &pt, &one, tweak);
|
|
|
|
if (secp256k1_gej_is_infinity(&pt)) {
|
|
return 0;
|
|
}
|
|
secp256k1_ge_set_gej(key, &pt);
|
|
return 1;
|
|
}
|
|
|
|
static int secp256k1_eckey_privkey_tweak_mul(secp256k1_scalar *key, const secp256k1_scalar *tweak) {
|
|
if (secp256k1_scalar_is_zero(tweak)) {
|
|
return 0;
|
|
}
|
|
|
|
secp256k1_scalar_mul(key, key, tweak);
|
|
return 1;
|
|
}
|
|
|
|
static int secp256k1_eckey_pubkey_tweak_mul(const secp256k1_ecmult_context *ctx, secp256k1_ge *key, const secp256k1_scalar *tweak) {
|
|
secp256k1_scalar zero;
|
|
secp256k1_gej pt;
|
|
if (secp256k1_scalar_is_zero(tweak)) {
|
|
return 0;
|
|
}
|
|
|
|
secp256k1_scalar_set_int(&zero, 0);
|
|
secp256k1_gej_set_ge(&pt, key);
|
|
secp256k1_ecmult(ctx, &pt, &pt, tweak, &zero);
|
|
secp256k1_ge_set_gej(key, &pt);
|
|
return 1;
|
|
}
|
|
|
|
#endif
|