peerplays_migrated/libraries/chain/confidential_evaluator.cpp

/*
 * Copyright (c) 2015 Cryptonomex, Inc., and contributors.
 *
 * The MIT License
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
#include <graphene/chain/exceptions.hpp>
#include <graphene/chain/protocol/confidential.hpp>
#include <graphene/chain/confidential_evaluator.hpp>
#include <graphene/chain/confidential_object.hpp>
#include <graphene/chain/database.hpp>
#include <graphene/chain/fba_accumulator_id.hpp>
#include <graphene/chain/hardfork.hpp>

namespace graphene { namespace chain {

void_result transfer_to_blind_evaluator::do_evaluate( const transfer_to_blind_operation& o )
{ try {
  const auto& d = db();
  if( d.head_block_time() < HARDFORK_SON_FOR_ETHEREUM_TIME )
  {
     const auto& atype = o.amount.asset_id(d);
     FC_ASSERT( atype.allow_confidential() );
     FC_ASSERT( !atype.is_transfer_restricted() );
     FC_ASSERT( !(atype.options.flags & white_list) );

     for( const auto& out : o.outputs )
     {
        for( const auto& a : out.owner.account_auths )
           a.first(d); // verify all accounts exist and are valid
     }
  }

  return void_result();
} FC_CAPTURE_AND_RETHROW( (o) ) }


void_result transfer_to_blind_evaluator::do_apply( const transfer_to_blind_operation& o )
{ try {
  if( db().head_block_time() < HARDFORK_SON_FOR_ETHEREUM_TIME ) {
     db().adjust_balance(o.from, -o.amount);

     const auto &add = o.amount.asset_id(db()).dynamic_asset_data_id(db()); // verify fee is a legit asset
     db().modify(add, [&](asset_dynamic_data_object &obj) {
        obj.confidential_supply += o.amount.amount;
        FC_ASSERT(obj.confidential_supply >= 0);
     });
     for (const auto &out : o.outputs) {
        db().create<blinded_balance_object>([&](blinded_balance_object &obj) {
           obj.asset_id = o.amount.asset_id;
           obj.owner = out.owner;
           obj.commitment = out.commitment;
        });
     }
  }
  return void_result();
} FC_CAPTURE_AND_RETHROW( (o) ) }

void transfer_to_blind_evaluator::pay_fee()
{
  const auto& d = db();
  if( d.head_block_time() < HARDFORK_SON_FOR_ETHEREUM_TIME ) {
     if (d.head_block_time() >= HARDFORK_563_TIME)
        pay_fba_fee(fba_accumulator_id_transfer_to_blind);
     else
        generic_evaluator::pay_fee();
  }
}

void_result transfer_from_blind_evaluator::do_evaluate( const transfer_from_blind_operation& o )
{ try {
  const auto& d = db();
  if( d.head_block_time() < HARDFORK_SON_FOR_ETHEREUM_TIME ) {
     o.fee.asset_id(d); // verify fee is a legit asset
     const auto &bbi = d.get_index_type<blinded_balance_index>();
     const auto &cidx = bbi.indices().get<by_commitment>();
     for (const auto &in : o.inputs) {
        auto itr = cidx.find(in.commitment);
        FC_ASSERT(itr != cidx.end());
        FC_ASSERT(itr->asset_id == o.fee.asset_id);
        FC_ASSERT(itr->owner == in.owner);
     }
  }
  return void_result();
} FC_CAPTURE_AND_RETHROW( (o) ) }

void_result transfer_from_blind_evaluator::do_apply( const transfer_from_blind_operation& o )
{ try {
  if( db().head_block_time() < HARDFORK_SON_FOR_ETHEREUM_TIME ) {
     db().adjust_balance(o.fee_payer(), o.fee);
     db().adjust_balance(o.to, o.amount);
     const auto &bbi = db().get_index_type<blinded_balance_index>();
     const auto &cidx = bbi.indices().get<by_commitment>();
     for (const auto &in : o.inputs) {
        auto itr = cidx.find(in.commitment);
        FC_ASSERT(itr != cidx.end());
        db().remove(*itr);
     }
     const auto &add = o.amount.asset_id(db()).dynamic_asset_data_id(db()); // verify fee is a legit asset
     db().modify(add, [&](asset_dynamic_data_object &obj) {
        obj.confidential_supply -= o.amount.amount + o.fee.amount;
        FC_ASSERT(obj.confidential_supply >= 0);
     });
  }
  return void_result();
} FC_CAPTURE_AND_RETHROW( (o) ) }

void transfer_from_blind_evaluator::pay_fee()
{
  const auto& d = db();
  if( d.head_block_time() < HARDFORK_SON_FOR_ETHEREUM_TIME ) {
     if (d.head_block_time() >= HARDFORK_563_TIME)
        pay_fba_fee(fba_accumulator_id_transfer_from_blind);
     else
        generic_evaluator::pay_fee();
  }
}

void_result blind_transfer_evaluator::do_evaluate( const blind_transfer_operation& o )
{ try {
  const auto& d = db();
  if( d.head_block_time() < HARDFORK_SON_FOR_ETHEREUM_TIME ) {
     o.fee.asset_id(d); // verify fee is a legit asset
     const auto &bbi = d.get_index_type<blinded_balance_index>();
     const auto &cidx = bbi.indices().get<by_commitment>();
     for (const auto &out : o.outputs) {
        for (const auto &a : out.owner.account_auths)
           a.first(d); // verify all accounts exist and are valid
     }
     for (const auto &in : o.inputs) {
        auto itr = cidx.find(in.commitment);
        GRAPHENE_ASSERT(itr != cidx.end(), blind_transfer_unknown_commitment, "", ("commitment", in.commitment));
        FC_ASSERT(itr->asset_id == o.fee.asset_id);
        FC_ASSERT(itr->owner == in.owner);
     }
  }
  return void_result();
} FC_CAPTURE_AND_RETHROW( (o) ) }

void_result blind_transfer_evaluator::do_apply( const blind_transfer_operation& o )
{ try {
  if( db().head_block_time() < HARDFORK_SON_FOR_ETHEREUM_TIME ) {
     db().adjust_balance(o.fee_payer(), o.fee); // deposit the fee to the temp account
     const auto &bbi = db().get_index_type<blinded_balance_index>();
     const auto &cidx = bbi.indices().get<by_commitment>();
     for (const auto &in : o.inputs) {
        auto itr = cidx.find(in.commitment);
        GRAPHENE_ASSERT(itr != cidx.end(), blind_transfer_unknown_commitment, "", ("commitment", in.commitment));
        db().remove(*itr);
     }
     for (const auto &out : o.outputs) {
        db().create<blinded_balance_object>([&](blinded_balance_object &obj) {
           obj.asset_id = o.fee.asset_id;
           obj.owner = out.owner;
           obj.commitment = out.commitment;
        });
     }
     const auto &add = o.fee.asset_id(db()).dynamic_asset_data_id(db());
     db().modify(add, [&](asset_dynamic_data_object &obj) {
        obj.confidential_supply -= o.fee.amount;
        FC_ASSERT(obj.confidential_supply >= 0);
     });
  }
  return void_result();
} FC_CAPTURE_AND_RETHROW( (o) ) }

void blind_transfer_evaluator::pay_fee()
{
  const auto& d = db();
  if( d.head_block_time() < HARDFORK_SON_FOR_ETHEREUM_TIME ) {
     if (d.head_block_time() >= HARDFORK_563_TIME)
        pay_fba_fee(fba_accumulator_id_blind_transfer);
     else
        generic_evaluator::pay_fee();
  }
}

} } // graphene::chain