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https://codeberg.org/anoncontributorxmr/monero.git
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e745c1e38d
The basic approach it to delegate all sensitive data (master key, secret ephemeral key, key derivation, ....) and related operations to the device. As device has low memory, it does not keep itself the values (except for view/spend keys) but once computed there are encrypted (with AES are equivalent) and return back to monero-wallet-cli. When they need to be manipulated by the device, they are decrypted on receive. Moreover, using the client for storing the value in encrypted form limits the modification in the client code. Those values are transfered from one C-structure to another one as previously. The code modification has been done with the wishes to be open to any other hardware wallet. To achieve that a C++ class hw::Device has been introduced. Two initial implementations are provided: the "default", which remaps all calls to initial Monero code, and the "Ledger", which delegates all calls to Ledger device.
578 lines
17 KiB
C++
578 lines
17 KiB
C++
// Copyright (c) 2014-2018, The Monero Project
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//
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// All rights reserved.
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//
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// Redistribution and use in source and binary forms, with or without modification, are
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// permitted provided that the following conditions are met:
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//
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// 1. Redistributions of source code must retain the above copyright notice, this list of
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// conditions and the following disclaimer.
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//
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// 2. Redistributions in binary form must reproduce the above copyright notice, this list
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// of conditions and the following disclaimer in the documentation and/or other
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// materials provided with the distribution.
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//
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// 3. Neither the name of the copyright holder nor the names of its contributors may be
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// used to endorse or promote products derived from this software without specific
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// prior written permission.
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//
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
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// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
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// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
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// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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//
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// Parts of this file are originally copyright (c) 2012-2013 The Cryptonote developers
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#include <unistd.h>
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#include <cassert>
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#include <cstddef>
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#include <cstdint>
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#include <cstdlib>
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#include <cstring>
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#include <memory>
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#include <boost/thread/mutex.hpp>
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#include <boost/thread/lock_guard.hpp>
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#include <boost/shared_ptr.hpp>
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#include "common/varint.h"
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#include "warnings.h"
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#include "crypto.h"
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#include "hash.h"
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namespace {
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static void local_abort(const char *msg)
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{
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fprintf(stderr, "%s\n", msg);
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#ifdef NDEBUG
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_exit(1);
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#else
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abort();
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#endif
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}
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}
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namespace crypto {
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using std::abort;
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using std::int32_t;
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using std::int64_t;
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using std::size_t;
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using std::uint32_t;
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using std::uint64_t;
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extern "C" {
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#include "crypto-ops.h"
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#include "random.h"
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}
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boost::mutex random_lock;
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static inline unsigned char *operator &(ec_point &point) {
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return &reinterpret_cast<unsigned char &>(point);
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}
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static inline const unsigned char *operator &(const ec_point &point) {
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return &reinterpret_cast<const unsigned char &>(point);
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}
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static inline unsigned char *operator &(ec_scalar &scalar) {
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return &reinterpret_cast<unsigned char &>(scalar);
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}
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static inline const unsigned char *operator &(const ec_scalar &scalar) {
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return &reinterpret_cast<const unsigned char &>(scalar);
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}
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/* generate a random 32-byte (256-bit) integer and copy it to res */
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static inline void random_scalar_not_thread_safe(ec_scalar &res) {
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unsigned char tmp[64];
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generate_random_bytes_not_thread_safe(64, tmp);
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sc_reduce(tmp);
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memcpy(&res, tmp, 32);
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}
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static inline void random_scalar(ec_scalar &res) {
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boost::lock_guard<boost::mutex> lock(random_lock);
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random_scalar_not_thread_safe(res);
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}
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void hash_to_scalar(const void *data, size_t length, ec_scalar &res) {
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cn_fast_hash(data, length, reinterpret_cast<hash &>(res));
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sc_reduce32(&res);
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}
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/*
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* generate public and secret keys from a random 256-bit integer
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* TODO: allow specifiying random value (for wallet recovery)
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*
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*/
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secret_key crypto_ops::generate_keys(public_key &pub, secret_key &sec, const secret_key& recovery_key, bool recover) {
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ge_p3 point;
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secret_key rng;
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if (recover)
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{
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rng = recovery_key;
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}
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else
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{
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random_scalar(rng);
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}
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sec = rng;
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sc_reduce32(&sec); // reduce in case second round of keys (sendkeys)
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ge_scalarmult_base(&point, &sec);
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ge_p3_tobytes(&pub, &point);
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return rng;
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}
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bool crypto_ops::check_key(const public_key &key) {
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ge_p3 point;
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return ge_frombytes_vartime(&point, &key) == 0;
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}
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bool crypto_ops::secret_key_to_public_key(const secret_key &sec, public_key &pub) {
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ge_p3 point;
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if (sc_check(&sec) != 0) {
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return false;
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}
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ge_scalarmult_base(&point, &sec);
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ge_p3_tobytes(&pub, &point);
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return true;
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}
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bool crypto_ops::generate_key_derivation(const public_key &key1, const secret_key &key2, key_derivation &derivation) {
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ge_p3 point;
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ge_p2 point2;
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ge_p1p1 point3;
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assert(sc_check(&key2) == 0);
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if (ge_frombytes_vartime(&point, &key1) != 0) {
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return false;
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}
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ge_scalarmult(&point2, &key2, &point);
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ge_mul8(&point3, &point2);
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ge_p1p1_to_p2(&point2, &point3);
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ge_tobytes(&derivation, &point2);
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return true;
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}
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void crypto_ops::derivation_to_scalar(const key_derivation &derivation, size_t output_index, ec_scalar &res) {
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struct {
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key_derivation derivation;
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char output_index[(sizeof(size_t) * 8 + 6) / 7];
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} buf;
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char *end = buf.output_index;
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buf.derivation = derivation;
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tools::write_varint(end, output_index);
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assert(end <= buf.output_index + sizeof buf.output_index);
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hash_to_scalar(&buf, end - reinterpret_cast<char *>(&buf), res);
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}
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bool crypto_ops::derive_public_key(const key_derivation &derivation, size_t output_index,
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const public_key &base, public_key &derived_key) {
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ec_scalar scalar;
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ge_p3 point1;
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ge_p3 point2;
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ge_cached point3;
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ge_p1p1 point4;
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ge_p2 point5;
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if (ge_frombytes_vartime(&point1, &base) != 0) {
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return false;
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}
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derivation_to_scalar(derivation, output_index, scalar);
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ge_scalarmult_base(&point2, &scalar);
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ge_p3_to_cached(&point3, &point2);
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ge_add(&point4, &point1, &point3);
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ge_p1p1_to_p2(&point5, &point4);
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ge_tobytes(&derived_key, &point5);
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return true;
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}
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void crypto_ops::derive_secret_key(const key_derivation &derivation, size_t output_index,
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const secret_key &base, secret_key &derived_key) {
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ec_scalar scalar;
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assert(sc_check(&base) == 0);
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derivation_to_scalar(derivation, output_index, scalar);
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sc_add(&derived_key, &base, &scalar);
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}
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bool crypto_ops::derive_subaddress_public_key(const public_key &out_key, const key_derivation &derivation, std::size_t output_index, public_key &derived_key) {
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ec_scalar scalar;
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ge_p3 point1;
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ge_p3 point2;
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ge_cached point3;
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ge_p1p1 point4;
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ge_p2 point5;
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if (ge_frombytes_vartime(&point1, &out_key) != 0) {
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return false;
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}
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derivation_to_scalar(derivation, output_index, scalar);
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ge_scalarmult_base(&point2, &scalar);
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ge_p3_to_cached(&point3, &point2);
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ge_sub(&point4, &point1, &point3);
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ge_p1p1_to_p2(&point5, &point4);
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ge_tobytes(&derived_key, &point5);
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return true;
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}
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struct s_comm {
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hash h;
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ec_point key;
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ec_point comm;
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};
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struct s_comm_2 {
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hash msg;
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ec_point D;
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ec_point X;
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ec_point Y;
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};
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void crypto_ops::generate_signature(const hash &prefix_hash, const public_key &pub, const secret_key &sec, signature &sig) {
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ge_p3 tmp3;
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ec_scalar k;
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s_comm buf;
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#if !defined(NDEBUG)
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{
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ge_p3 t;
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public_key t2;
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assert(sc_check(&sec) == 0);
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ge_scalarmult_base(&t, &sec);
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ge_p3_tobytes(&t2, &t);
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assert(pub == t2);
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}
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#endif
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buf.h = prefix_hash;
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buf.key = pub;
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random_scalar(k);
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ge_scalarmult_base(&tmp3, &k);
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ge_p3_tobytes(&buf.comm, &tmp3);
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hash_to_scalar(&buf, sizeof(s_comm), sig.c);
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sc_mulsub(&sig.r, &sig.c, &sec, &k);
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}
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bool crypto_ops::check_signature(const hash &prefix_hash, const public_key &pub, const signature &sig) {
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ge_p2 tmp2;
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ge_p3 tmp3;
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ec_scalar c;
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s_comm buf;
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assert(check_key(pub));
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buf.h = prefix_hash;
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buf.key = pub;
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if (ge_frombytes_vartime(&tmp3, &pub) != 0) {
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return false;
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}
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if (sc_check(&sig.c) != 0 || sc_check(&sig.r) != 0) {
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return false;
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}
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ge_double_scalarmult_base_vartime(&tmp2, &sig.c, &tmp3, &sig.r);
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ge_tobytes(&buf.comm, &tmp2);
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hash_to_scalar(&buf, sizeof(s_comm), c);
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sc_sub(&c, &c, &sig.c);
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return sc_isnonzero(&c) == 0;
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}
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void crypto_ops::generate_tx_proof(const hash &prefix_hash, const public_key &R, const public_key &A, const boost::optional<public_key> &B, const public_key &D, const secret_key &r, signature &sig) {
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// sanity check
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ge_p3 R_p3;
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ge_p3 A_p3;
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ge_p3 B_p3;
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ge_p3 D_p3;
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if (ge_frombytes_vartime(&R_p3, &R) != 0) throw std::runtime_error("tx pubkey is invalid");
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if (ge_frombytes_vartime(&A_p3, &A) != 0) throw std::runtime_error("recipient view pubkey is invalid");
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if (B && ge_frombytes_vartime(&B_p3, &*B) != 0) throw std::runtime_error("recipient spend pubkey is invalid");
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if (ge_frombytes_vartime(&D_p3, &D) != 0) throw std::runtime_error("key derivation is invalid");
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#if !defined(NDEBUG)
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{
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assert(sc_check(&r) == 0);
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// check R == r*G or R == r*B
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public_key dbg_R;
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if (B)
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{
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ge_p2 dbg_R_p2;
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ge_scalarmult(&dbg_R_p2, &r, &B_p3);
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ge_tobytes(&dbg_R, &dbg_R_p2);
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}
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else
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{
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ge_p3 dbg_R_p3;
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ge_scalarmult_base(&dbg_R_p3, &r);
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ge_p3_tobytes(&dbg_R, &dbg_R_p3);
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}
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assert(R == dbg_R);
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// check D == r*A
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ge_p2 dbg_D_p2;
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ge_scalarmult(&dbg_D_p2, &r, &A_p3);
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public_key dbg_D;
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ge_tobytes(&dbg_D, &dbg_D_p2);
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assert(D == dbg_D);
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}
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#endif
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// pick random k
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ec_scalar k;
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random_scalar(k);
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s_comm_2 buf;
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buf.msg = prefix_hash;
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buf.D = D;
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if (B)
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{
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// compute X = k*B
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ge_p2 X_p2;
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ge_scalarmult(&X_p2, &k, &B_p3);
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ge_tobytes(&buf.X, &X_p2);
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}
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else
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{
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// compute X = k*G
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ge_p3 X_p3;
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ge_scalarmult_base(&X_p3, &k);
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ge_p3_tobytes(&buf.X, &X_p3);
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}
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// compute Y = k*A
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ge_p2 Y_p2;
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ge_scalarmult(&Y_p2, &k, &A_p3);
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ge_tobytes(&buf.Y, &Y_p2);
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// sig.c = Hs(Msg || D || X || Y)
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hash_to_scalar(&buf, sizeof(buf), sig.c);
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// sig.r = k - sig.c*r
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sc_mulsub(&sig.r, &sig.c, &r, &k);
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}
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bool crypto_ops::check_tx_proof(const hash &prefix_hash, const public_key &R, const public_key &A, const boost::optional<public_key> &B, const public_key &D, const signature &sig) {
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// sanity check
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ge_p3 R_p3;
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ge_p3 A_p3;
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ge_p3 B_p3;
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ge_p3 D_p3;
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if (ge_frombytes_vartime(&R_p3, &R) != 0) return false;
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if (ge_frombytes_vartime(&A_p3, &A) != 0) return false;
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if (B && ge_frombytes_vartime(&B_p3, &*B) != 0) return false;
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if (ge_frombytes_vartime(&D_p3, &D) != 0) return false;
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if (sc_check(&sig.c) != 0 || sc_check(&sig.r) != 0) return false;
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// compute sig.c*R
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ge_p3 cR_p3;
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{
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ge_p2 cR_p2;
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ge_scalarmult(&cR_p2, &sig.c, &R_p3);
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public_key cR;
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ge_tobytes(&cR, &cR_p2);
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if (ge_frombytes_vartime(&cR_p3, &cR) != 0) return false;
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}
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ge_p1p1 X_p1p1;
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if (B)
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{
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// compute X = sig.c*R + sig.r*B
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ge_p2 rB_p2;
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ge_scalarmult(&rB_p2, &sig.r, &B_p3);
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public_key rB;
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ge_tobytes(&rB, &rB_p2);
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ge_p3 rB_p3;
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if (ge_frombytes_vartime(&rB_p3, &rB) != 0) return false;
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ge_cached rB_cached;
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ge_p3_to_cached(&rB_cached, &rB_p3);
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ge_add(&X_p1p1, &cR_p3, &rB_cached);
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}
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else
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{
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// compute X = sig.c*R + sig.r*G
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ge_p3 rG_p3;
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ge_scalarmult_base(&rG_p3, &sig.r);
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ge_cached rG_cached;
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ge_p3_to_cached(&rG_cached, &rG_p3);
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ge_add(&X_p1p1, &cR_p3, &rG_cached);
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}
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ge_p2 X_p2;
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ge_p1p1_to_p2(&X_p2, &X_p1p1);
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// compute sig.c*D
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ge_p2 cD_p2;
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ge_scalarmult(&cD_p2, &sig.c, &D_p3);
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// compute sig.r*A
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ge_p2 rA_p2;
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ge_scalarmult(&rA_p2, &sig.r, &A_p3);
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// compute Y = sig.c*D + sig.r*A
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public_key cD;
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public_key rA;
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ge_tobytes(&cD, &cD_p2);
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ge_tobytes(&rA, &rA_p2);
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ge_p3 cD_p3;
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ge_p3 rA_p3;
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if (ge_frombytes_vartime(&cD_p3, &cD) != 0) return false;
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if (ge_frombytes_vartime(&rA_p3, &rA) != 0) return false;
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ge_cached rA_cached;
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ge_p3_to_cached(&rA_cached, &rA_p3);
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ge_p1p1 Y_p1p1;
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ge_add(&Y_p1p1, &cD_p3, &rA_cached);
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ge_p2 Y_p2;
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ge_p1p1_to_p2(&Y_p2, &Y_p1p1);
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// compute c2 = Hs(Msg || D || X || Y)
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s_comm_2 buf;
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buf.msg = prefix_hash;
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buf.D = D;
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ge_tobytes(&buf.X, &X_p2);
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ge_tobytes(&buf.Y, &Y_p2);
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ec_scalar c2;
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hash_to_scalar(&buf, sizeof(s_comm_2), c2);
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// test if c2 == sig.c
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sc_sub(&c2, &c2, &sig.c);
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return sc_isnonzero(&c2) == 0;
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}
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void crypto_ops::hash_to_ec(const public_key &key, ge_p3 &res) {
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hash h;
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ge_p2 point;
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ge_p1p1 point2;
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cn_fast_hash(std::addressof(key), sizeof(public_key), h);
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ge_fromfe_frombytes_vartime(&point, reinterpret_cast<const unsigned char *>(&h));
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ge_mul8(&point2, &point);
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ge_p1p1_to_p3(&res, &point2);
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}
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void crypto_ops::generate_key_image(const public_key &pub, const secret_key &sec, key_image &image) {
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ge_p3 point;
|
|
ge_p2 point2;
|
|
assert(sc_check(&sec) == 0);
|
|
hash_to_ec(pub, point);
|
|
ge_scalarmult(&point2, &sec, &point);
|
|
ge_tobytes(&image, &point2);
|
|
}
|
|
|
|
PUSH_WARNINGS
|
|
DISABLE_VS_WARNINGS(4200)
|
|
struct ec_point_pair {
|
|
ec_point a, b;
|
|
};
|
|
struct rs_comm {
|
|
hash h;
|
|
struct ec_point_pair ab[];
|
|
};
|
|
POP_WARNINGS
|
|
|
|
static inline size_t rs_comm_size(size_t pubs_count) {
|
|
return sizeof(rs_comm) + pubs_count * sizeof(ec_point_pair);
|
|
}
|
|
|
|
void crypto_ops::generate_ring_signature(const hash &prefix_hash, const key_image &image,
|
|
const public_key *const *pubs, size_t pubs_count,
|
|
const secret_key &sec, size_t sec_index,
|
|
signature *sig) {
|
|
size_t i;
|
|
ge_p3 image_unp;
|
|
ge_dsmp image_pre;
|
|
ec_scalar sum, k, h;
|
|
boost::shared_ptr<rs_comm> buf(reinterpret_cast<rs_comm *>(malloc(rs_comm_size(pubs_count))), free);
|
|
if (!buf)
|
|
local_abort("malloc failure");
|
|
assert(sec_index < pubs_count);
|
|
#if !defined(NDEBUG)
|
|
{
|
|
ge_p3 t;
|
|
public_key t2;
|
|
key_image t3;
|
|
assert(sc_check(&sec) == 0);
|
|
ge_scalarmult_base(&t, &sec);
|
|
ge_p3_tobytes(&t2, &t);
|
|
assert(*pubs[sec_index] == t2);
|
|
generate_key_image(*pubs[sec_index], sec, t3);
|
|
assert(image == t3);
|
|
for (i = 0; i < pubs_count; i++) {
|
|
assert(check_key(*pubs[i]));
|
|
}
|
|
}
|
|
#endif
|
|
if (ge_frombytes_vartime(&image_unp, &image) != 0) {
|
|
local_abort("invalid key image");
|
|
}
|
|
ge_dsm_precomp(image_pre, &image_unp);
|
|
sc_0(&sum);
|
|
buf->h = prefix_hash;
|
|
for (i = 0; i < pubs_count; i++) {
|
|
ge_p2 tmp2;
|
|
ge_p3 tmp3;
|
|
if (i == sec_index) {
|
|
random_scalar(k);
|
|
ge_scalarmult_base(&tmp3, &k);
|
|
ge_p3_tobytes(&buf->ab[i].a, &tmp3);
|
|
hash_to_ec(*pubs[i], tmp3);
|
|
ge_scalarmult(&tmp2, &k, &tmp3);
|
|
ge_tobytes(&buf->ab[i].b, &tmp2);
|
|
} else {
|
|
random_scalar(sig[i].c);
|
|
random_scalar(sig[i].r);
|
|
if (ge_frombytes_vartime(&tmp3, &*pubs[i]) != 0) {
|
|
local_abort("invalid pubkey");
|
|
}
|
|
ge_double_scalarmult_base_vartime(&tmp2, &sig[i].c, &tmp3, &sig[i].r);
|
|
ge_tobytes(&buf->ab[i].a, &tmp2);
|
|
hash_to_ec(*pubs[i], tmp3);
|
|
ge_double_scalarmult_precomp_vartime(&tmp2, &sig[i].r, &tmp3, &sig[i].c, image_pre);
|
|
ge_tobytes(&buf->ab[i].b, &tmp2);
|
|
sc_add(&sum, &sum, &sig[i].c);
|
|
}
|
|
}
|
|
hash_to_scalar(buf.get(), rs_comm_size(pubs_count), h);
|
|
sc_sub(&sig[sec_index].c, &h, &sum);
|
|
sc_mulsub(&sig[sec_index].r, &sig[sec_index].c, &sec, &k);
|
|
}
|
|
|
|
bool crypto_ops::check_ring_signature(const hash &prefix_hash, const key_image &image,
|
|
const public_key *const *pubs, size_t pubs_count,
|
|
const signature *sig) {
|
|
size_t i;
|
|
ge_p3 image_unp;
|
|
ge_dsmp image_pre;
|
|
ec_scalar sum, h;
|
|
boost::shared_ptr<rs_comm> buf(reinterpret_cast<rs_comm *>(malloc(rs_comm_size(pubs_count))), free);
|
|
if (!buf)
|
|
return false;
|
|
#if !defined(NDEBUG)
|
|
for (i = 0; i < pubs_count; i++) {
|
|
assert(check_key(*pubs[i]));
|
|
}
|
|
#endif
|
|
if (ge_frombytes_vartime(&image_unp, &image) != 0) {
|
|
return false;
|
|
}
|
|
ge_dsm_precomp(image_pre, &image_unp);
|
|
sc_0(&sum);
|
|
buf->h = prefix_hash;
|
|
for (i = 0; i < pubs_count; i++) {
|
|
ge_p2 tmp2;
|
|
ge_p3 tmp3;
|
|
if (sc_check(&sig[i].c) != 0 || sc_check(&sig[i].r) != 0) {
|
|
return false;
|
|
}
|
|
if (ge_frombytes_vartime(&tmp3, &*pubs[i]) != 0) {
|
|
return false;
|
|
}
|
|
ge_double_scalarmult_base_vartime(&tmp2, &sig[i].c, &tmp3, &sig[i].r);
|
|
ge_tobytes(&buf->ab[i].a, &tmp2);
|
|
hash_to_ec(*pubs[i], tmp3);
|
|
ge_double_scalarmult_precomp_vartime(&tmp2, &sig[i].r, &tmp3, &sig[i].c, image_pre);
|
|
ge_tobytes(&buf->ab[i].b, &tmp2);
|
|
sc_add(&sum, &sum, &sig[i].c);
|
|
}
|
|
hash_to_scalar(buf.get(), rs_comm_size(pubs_count), h);
|
|
sc_sub(&h, &h, &sum);
|
|
return sc_isnonzero(&h) == 0;
|
|
}
|
|
}
|