mirror of
https://codeberg.org/anoncontributorxmr/monero.git
synced 2024-11-30 14:53:27 +01:00
476 lines
15 KiB
C++
476 lines
15 KiB
C++
// Copyright (c) 2016, Monero Research Labs
|
|
//
|
|
// Author: Shen Noether <shen.noether@gmx.com>
|
|
//
|
|
// All rights reserved.
|
|
//
|
|
// Redistribution and use in source and binary forms, with or without modification, are
|
|
// permitted provided that the following conditions are met:
|
|
//
|
|
// 1. Redistributions of source code must retain the above copyright notice, this list of
|
|
// conditions and the following disclaimer.
|
|
//
|
|
// 2. Redistributions in binary form must reproduce the above copyright notice, this list
|
|
// of conditions and the following disclaimer in the documentation and/or other
|
|
// materials provided with the distribution.
|
|
//
|
|
// 3. Neither the name of the copyright holder nor the names of its contributors may be
|
|
// used to endorse or promote products derived from this software without specific
|
|
// prior written permission.
|
|
//
|
|
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
|
|
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
|
|
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
|
|
// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
|
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
|
|
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
|
|
// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
|
|
// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
|
|
#include "misc_log_ex.h"
|
|
#include "rctOps.h"
|
|
using namespace crypto;
|
|
using namespace std;
|
|
|
|
namespace rct {
|
|
|
|
//Various key initialization functions
|
|
|
|
//Creates a zero scalar
|
|
void zero(key &zero) {
|
|
memset(&zero, 0, 32);
|
|
}
|
|
|
|
//Creates a zero scalar
|
|
key zero() {
|
|
static const key z = { {0x00, 0x00, 0x00,0x00 , 0x00, 0x00, 0x00,0x00 , 0x00, 0x00, 0x00,0x00 , 0x00, 0x00, 0x00,0x00 , 0x00, 0x00, 0x00,0x00 , 0x00, 0x00, 0x00,0x00 , 0x00, 0x00, 0x00,0x00 , 0x00, 0x00, 0x00,0x00 } };
|
|
return z;
|
|
}
|
|
|
|
//Creates a zero elliptic curve point
|
|
void identity(key &Id) {
|
|
Id[0] = (unsigned char)(0x01);
|
|
memset(Id.bytes+1, 0, 31);
|
|
}
|
|
|
|
//Creates a zero elliptic curve point
|
|
key identity() {
|
|
key Id;
|
|
Id[0] = (unsigned char)(0x01);
|
|
memset(Id.bytes+1, 0, 31);
|
|
return Id;
|
|
}
|
|
|
|
//copies a scalar or point
|
|
void copy(key &AA, const key &A) {
|
|
memcpy(&AA, &A, 32);
|
|
}
|
|
|
|
//copies a scalar or point
|
|
key copy(const key &A) {
|
|
key AA;
|
|
memcpy(&AA, &A, 32);
|
|
return AA;
|
|
}
|
|
|
|
|
|
//initializes a key matrix;
|
|
//first parameter is rows,
|
|
//second is columns
|
|
keyM keyMInit(int rows, int cols) {
|
|
keyM rv(cols);
|
|
int i = 0;
|
|
for (i = 0 ; i < cols ; i++) {
|
|
rv[i] = keyV(rows);
|
|
}
|
|
return rv;
|
|
}
|
|
|
|
|
|
|
|
|
|
//Various key generation functions
|
|
|
|
//generates a random scalar which can be used as a secret key or mask
|
|
void skGen(key &sk) {
|
|
sk = crypto::rand<key>();
|
|
sc_reduce32(sk.bytes);
|
|
}
|
|
|
|
//generates a random scalar which can be used as a secret key or mask
|
|
key skGen() {
|
|
key sk = crypto::rand<key>();
|
|
sc_reduce32(sk.bytes);
|
|
return sk;
|
|
}
|
|
|
|
//Generates a vector of secret key
|
|
//Mainly used in testing
|
|
keyV skvGen(int rows ) {
|
|
keyV rv(rows);
|
|
int i = 0;
|
|
for (i = 0 ; i < rows ; i++) {
|
|
skGen(rv[i]);
|
|
}
|
|
return rv;
|
|
}
|
|
|
|
//generates a random curve point (for testing)
|
|
key pkGen() {
|
|
key sk = skGen();
|
|
key pk = scalarmultBase(sk);
|
|
return pk;
|
|
}
|
|
|
|
//generates a random secret and corresponding public key
|
|
void skpkGen(key &sk, key &pk) {
|
|
skGen(sk);
|
|
scalarmultBase(pk, sk);
|
|
}
|
|
|
|
//generates a random secret and corresponding public key
|
|
tuple<key, key> skpkGen() {
|
|
key sk = skGen();
|
|
key pk = scalarmultBase(sk);
|
|
return make_tuple(sk, pk);
|
|
}
|
|
|
|
//generates C =aG + bH from b, a is given..
|
|
void genC(key & C, const key & a, xmr_amount amount) {
|
|
key bH = scalarmultH(d2h(amount));
|
|
addKeys1(C, a, bH);
|
|
}
|
|
|
|
//generates a <secret , public> / Pedersen commitment to the amount
|
|
tuple<ctkey, ctkey> ctskpkGen(xmr_amount amount) {
|
|
ctkey sk, pk;
|
|
skpkGen(sk.dest, pk.dest);
|
|
skpkGen(sk.mask, pk.mask);
|
|
key am = d2h(amount);
|
|
key bH = scalarmultH(am);
|
|
addKeys(pk.mask, pk.mask, bH);
|
|
return make_tuple(sk, pk);
|
|
}
|
|
|
|
|
|
//generates a <secret , public> / Pedersen commitment but takes bH as input
|
|
tuple<ctkey, ctkey> ctskpkGen(key bH) {
|
|
ctkey sk, pk;
|
|
skpkGen(sk.dest, pk.dest);
|
|
skpkGen(sk.mask, pk.mask);
|
|
addKeys(pk.mask, pk.mask, bH);
|
|
return make_tuple(sk, pk);
|
|
}
|
|
|
|
key zeroCommit(xmr_amount amount) {
|
|
key mask = identity();
|
|
mask = scalarmultBase(mask);
|
|
key am = d2h(amount);
|
|
key bH = scalarmultH(am);
|
|
addKeys(mask, mask, bH);
|
|
return mask;
|
|
}
|
|
|
|
key commit(xmr_amount amount, key mask) {
|
|
mask = scalarmultBase(mask);
|
|
key am = d2h(amount);
|
|
key bH = scalarmultH(am);
|
|
addKeys(mask, mask, bH);
|
|
return mask;
|
|
}
|
|
|
|
//generates a random uint long long (for testing)
|
|
xmr_amount randXmrAmount(xmr_amount upperlimit) {
|
|
return h2d(skGen()) % (upperlimit);
|
|
}
|
|
|
|
//Scalar multiplications of curve points
|
|
|
|
//does a * G where a is a scalar and G is the curve basepoint
|
|
void scalarmultBase(key &aG,const key &a) {
|
|
ge_p3 point;
|
|
sc_reduce32copy(aG.bytes, a.bytes); //do this beforehand!
|
|
ge_scalarmult_base(&point, aG.bytes);
|
|
ge_p3_tobytes(aG.bytes, &point);
|
|
}
|
|
|
|
//does a * G where a is a scalar and G is the curve basepoint
|
|
key scalarmultBase(const key & a) {
|
|
ge_p3 point;
|
|
key aG;
|
|
sc_reduce32copy(aG.bytes, a.bytes); //do this beforehand
|
|
ge_scalarmult_base(&point, aG.bytes);
|
|
ge_p3_tobytes(aG.bytes, &point);
|
|
return aG;
|
|
}
|
|
|
|
//does a * P where a is a scalar and P is an arbitrary point
|
|
void scalarmultKey(key & aP, const key &P, const key &a) {
|
|
ge_p3 A;
|
|
ge_p2 R;
|
|
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&A, P.bytes) == 0, "ge_frombytes_vartime failed at "+boost::lexical_cast<std::string>(__LINE__));
|
|
ge_scalarmult(&R, a.bytes, &A);
|
|
ge_tobytes(aP.bytes, &R);
|
|
}
|
|
|
|
//does a * P where a is a scalar and P is an arbitrary point
|
|
key scalarmultKey(const key & P, const key & a) {
|
|
ge_p3 A;
|
|
ge_p2 R;
|
|
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&A, P.bytes) == 0, "ge_frombytes_vartime failed at "+boost::lexical_cast<std::string>(__LINE__));
|
|
ge_scalarmult(&R, a.bytes, &A);
|
|
key aP;
|
|
ge_tobytes(aP.bytes, &R);
|
|
return aP;
|
|
}
|
|
|
|
|
|
//Computes aH where H= toPoint(cn_fast_hash(G)), G the basepoint
|
|
key scalarmultH(const key & a) {
|
|
ge_p3 A;
|
|
ge_p2 R;
|
|
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&A, H.bytes) == 0, "ge_frombytes_vartime failed at "+boost::lexical_cast<std::string>(__LINE__));
|
|
ge_scalarmult(&R, a.bytes, &A);
|
|
key aP;
|
|
ge_tobytes(aP.bytes, &R);
|
|
return aP;
|
|
}
|
|
|
|
//Curve addition / subtractions
|
|
|
|
//for curve points: AB = A + B
|
|
void addKeys(key &AB, const key &A, const key &B) {
|
|
ge_p3 B2, A2;
|
|
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&B2, B.bytes) == 0, "ge_frombytes_vartime failed at "+boost::lexical_cast<std::string>(__LINE__));
|
|
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&A2, A.bytes) == 0, "ge_frombytes_vartime failed at "+boost::lexical_cast<std::string>(__LINE__));
|
|
ge_cached tmp2;
|
|
ge_p3_to_cached(&tmp2, &B2);
|
|
ge_p1p1 tmp3;
|
|
ge_add(&tmp3, &A2, &tmp2);
|
|
ge_p1p1_to_p3(&A2, &tmp3);
|
|
ge_p3_tobytes(AB.bytes, &A2);
|
|
}
|
|
|
|
|
|
//addKeys1
|
|
//aGB = aG + B where a is a scalar, G is the basepoint, and B is a point
|
|
void addKeys1(key &aGB, const key &a, const key & B) {
|
|
key aG = scalarmultBase(a);
|
|
addKeys(aGB, aG, B);
|
|
}
|
|
|
|
//addKeys2
|
|
//aGbB = aG + bB where a, b are scalars, G is the basepoint and B is a point
|
|
void addKeys2(key &aGbB, const key &a, const key &b, const key & B) {
|
|
ge_p2 rv;
|
|
ge_p3 B2;
|
|
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&B2, B.bytes) == 0, "ge_frombytes_vartime failed at "+boost::lexical_cast<std::string>(__LINE__));
|
|
ge_double_scalarmult_base_vartime(&rv, b.bytes, &B2, a.bytes);
|
|
ge_tobytes(aGbB.bytes, &rv);
|
|
}
|
|
|
|
//Does some precomputation to make addKeys3 more efficient
|
|
// input B a curve point and output a ge_dsmp which has precomputation applied
|
|
void precomp(ge_dsmp rv, const key & B) {
|
|
ge_p3 B2;
|
|
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&B2, B.bytes) == 0, "ge_frombytes_vartime failed at "+boost::lexical_cast<std::string>(__LINE__));
|
|
ge_dsm_precomp(rv, &B2);
|
|
}
|
|
|
|
//addKeys3
|
|
//aAbB = a*A + b*B where a, b are scalars, A, B are curve points
|
|
//B must be input after applying "precomp"
|
|
void addKeys3(key &aAbB, const key &a, const key &A, const key &b, const ge_dsmp B) {
|
|
ge_p2 rv;
|
|
ge_p3 A2;
|
|
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&A2, A.bytes) == 0, "ge_frombytes_vartime failed at "+boost::lexical_cast<std::string>(__LINE__));
|
|
ge_double_scalarmult_precomp_vartime(&rv, a.bytes, &A2, b.bytes, B);
|
|
ge_tobytes(aAbB.bytes, &rv);
|
|
}
|
|
|
|
|
|
//subtract Keys (subtracts curve points)
|
|
//AB = A - B where A, B are curve points
|
|
void subKeys(key & AB, const key &A, const key &B) {
|
|
ge_p3 B2, A2;
|
|
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&B2, B.bytes) == 0, "ge_frombytes_vartime failed at "+boost::lexical_cast<std::string>(__LINE__));
|
|
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&A2, A.bytes) == 0, "ge_frombytes_vartime failed at "+boost::lexical_cast<std::string>(__LINE__));
|
|
ge_cached tmp2;
|
|
ge_p3_to_cached(&tmp2, &B2);
|
|
ge_p1p1 tmp3;
|
|
ge_sub(&tmp3, &A2, &tmp2);
|
|
ge_p1p1_to_p3(&A2, &tmp3);
|
|
ge_p3_tobytes(AB.bytes, &A2);
|
|
}
|
|
|
|
//checks if A, B are equal as curve points
|
|
//without doing curve operations
|
|
bool equalKeys(const key & a, const key & b) {
|
|
bool rv = true;
|
|
for (int i = 0; i < 32; ++i) {
|
|
if (a.bytes[i] != b.bytes[i]) {
|
|
rv = false;
|
|
}
|
|
}
|
|
return rv;
|
|
}
|
|
|
|
//Hashing - cn_fast_hash
|
|
//be careful these are also in crypto namespace
|
|
//cn_fast_hash for arbitrary multiples of 32 bytes
|
|
void cn_fast_hash(key &hash, const void * data, const std::size_t l) {
|
|
keccak((uint8_t *)data, l, hash.bytes, 32);
|
|
}
|
|
|
|
void hash_to_scalar(key &hash, const void * data, const std::size_t l) {
|
|
cn_fast_hash(hash, data, l);
|
|
sc_reduce32(hash.bytes);
|
|
}
|
|
|
|
//cn_fast_hash for a 32 byte key
|
|
void cn_fast_hash(key & hash, const key & in) {
|
|
keccak((uint8_t *)in.bytes, 32, hash.bytes, 32);
|
|
}
|
|
|
|
void hash_to_scalar(key & hash, const key & in) {
|
|
cn_fast_hash(hash, in);
|
|
sc_reduce32(hash.bytes);
|
|
}
|
|
|
|
//cn_fast_hash for a 32 byte key
|
|
key cn_fast_hash(const key & in) {
|
|
key hash;
|
|
keccak((uint8_t *)in.bytes, 32, hash.bytes, 32);
|
|
return hash;
|
|
}
|
|
|
|
key hash_to_scalar(const key & in) {
|
|
key hash = cn_fast_hash(in);
|
|
sc_reduce32(hash.bytes);
|
|
return hash;
|
|
}
|
|
|
|
//cn_fast_hash for a 128 byte unsigned char
|
|
key cn_fast_hash128(const void * in) {
|
|
key hash;
|
|
keccak((uint8_t *)in, 128, hash.bytes, 32);
|
|
return hash;
|
|
}
|
|
|
|
key hash_to_scalar128(const void * in) {
|
|
key hash = cn_fast_hash128(in);
|
|
sc_reduce32(hash.bytes);
|
|
return hash;
|
|
}
|
|
|
|
//cn_fast_hash for multisig purpose
|
|
//This takes the outputs and commitments
|
|
//and hashes them into a 32 byte sized key
|
|
key cn_fast_hash(ctkeyV PC) {
|
|
key rv = identity();
|
|
std::size_t l = (std::size_t)PC.size();
|
|
size_t i = 0, j = 0;
|
|
vector<char> m(l * 64);
|
|
for (i = 0 ; i < l ; i++) {
|
|
memcpy(&m[i * 64], &PC[i].dest, 32);
|
|
memcpy(&m[i * 64 + 32], &PC[i].mask, 32);
|
|
}
|
|
cn_fast_hash(rv, &m[0], 64*l);
|
|
return rv;
|
|
}
|
|
|
|
key hash_to_scalar(ctkeyV PC) {
|
|
key rv = cn_fast_hash(PC);
|
|
sc_reduce32(rv.bytes);
|
|
return rv;
|
|
}
|
|
|
|
//cn_fast_hash for a key-vector of arbitrary length
|
|
//this is useful since you take a number of keys
|
|
//put them in the key vector and it concatenates them
|
|
//and then hashes them
|
|
key cn_fast_hash(const keyV &keys) {
|
|
size_t l = keys.size();
|
|
vector<unsigned char> m(l * 32);
|
|
size_t i;
|
|
for (i = 0 ; i < l ; i++) {
|
|
memcpy(&m[i * 32], keys[i].bytes, 32);
|
|
}
|
|
key rv;
|
|
cn_fast_hash(rv, &m[0], 32 * l);
|
|
//dp(rv);
|
|
return rv;
|
|
}
|
|
|
|
key hash_to_scalar(const keyV &keys) {
|
|
key rv = cn_fast_hash(keys);
|
|
sc_reduce32(rv.bytes);
|
|
return rv;
|
|
}
|
|
|
|
key hashToPointSimple(const key & hh) {
|
|
key pointk;
|
|
ge_p1p1 point2;
|
|
ge_p2 point;
|
|
ge_p3 res;
|
|
key h = cn_fast_hash(hh);
|
|
CHECK_AND_ASSERT_THROW_MES(ge_frombytes_vartime(&res, h.bytes) == 0, "ge_frombytes_vartime failed at "+boost::lexical_cast<std::string>(__LINE__));
|
|
ge_p3_to_p2(&point, &res);
|
|
ge_mul8(&point2, &point);
|
|
ge_p1p1_to_p3(&res, &point2);
|
|
ge_p3_tobytes(pointk.bytes, &res);
|
|
return pointk;
|
|
}
|
|
|
|
key hashToPoint(const key & hh) {
|
|
key pointk;
|
|
ge_p2 point;
|
|
ge_p1p1 point2;
|
|
ge_p3 res;
|
|
key h = cn_fast_hash(hh);
|
|
ge_fromfe_frombytes_vartime(&point, h.bytes);
|
|
ge_mul8(&point2, &point);
|
|
ge_p1p1_to_p3(&res, &point2);
|
|
ge_p3_tobytes(pointk.bytes, &res);
|
|
return pointk;
|
|
}
|
|
|
|
void hashToPoint(key & pointk, const key & hh) {
|
|
ge_p2 point;
|
|
ge_p1p1 point2;
|
|
ge_p3 res;
|
|
key h = cn_fast_hash(hh);
|
|
ge_fromfe_frombytes_vartime(&point, h.bytes);
|
|
ge_mul8(&point2, &point);
|
|
ge_p1p1_to_p3(&res, &point2);
|
|
ge_p3_tobytes(pointk.bytes, &res);
|
|
}
|
|
|
|
//sums a vector of curve points (for scalars use sc_add)
|
|
void sumKeys(key & Csum, const keyV & Cis) {
|
|
identity(Csum);
|
|
size_t i = 0;
|
|
for (i = 0; i < Cis.size(); i++) {
|
|
addKeys(Csum, Csum, Cis[i]);
|
|
}
|
|
}
|
|
|
|
//Elliptic Curve Diffie Helman: encodes and decodes the amount b and mask a
|
|
// where C= aG + bH
|
|
void ecdhEncode(ecdhTuple & unmasked, const key & sharedSec) {
|
|
key sharedSec1 = hash_to_scalar(sharedSec);
|
|
key sharedSec2 = hash_to_scalar(sharedSec1);
|
|
//encode
|
|
sc_add(unmasked.mask.bytes, unmasked.mask.bytes, sharedSec1.bytes);
|
|
sc_add(unmasked.amount.bytes, unmasked.amount.bytes, sharedSec2.bytes);
|
|
}
|
|
void ecdhDecode(ecdhTuple & masked, const key & sharedSec) {
|
|
key sharedSec1 = hash_to_scalar(sharedSec);
|
|
key sharedSec2 = hash_to_scalar(sharedSec1);
|
|
//decode
|
|
sc_sub(masked.mask.bytes, masked.mask.bytes, sharedSec1.bytes);
|
|
sc_sub(masked.amount.bytes, masked.amount.bytes, sharedSec2.bytes);
|
|
}
|
|
}
|