Restore duplicate work check for legacy PoW #256

steemit · Aug 12, 2016 · 42d0523 · 42d0523
1 parent 35e061a
commit 42d0523
Show file tree

Hide file tree

Showing 2 changed files with 16 additions and 0 deletions.
diff --git a/libraries/chain/include/steemit/chain/witness_objects.hpp b/libraries/chain/include/steemit/chain/witness_objects.hpp
@@ -85,6 +85,8 @@ namespace steemit { namespace chain {
          fc::uint128 virtual_scheduled_time = fc::uint128::max_value();
          ///@}
 
+         digest_type last_work;
+
          /**
           * This field represents the Steem blockchain version the witness is running.
           */
@@ -132,6 +134,7 @@ namespace steemit { namespace chain {
       witness_object,
       indexed_by<
          ordered_unique< tag<by_id>, member< object, object_id_type, &object::id > >,
+         ordered_non_unique< tag<by_work>, member<witness_object, digest_type, &witness_object::last_work> >,
          ordered_unique< tag<by_name>, member<witness_object, string, &witness_object::owner> >,
          ordered_non_unique< tag<by_pow>, member<witness_object, uint64_t, &witness_object::pow_worker> >,
          ordered_unique< tag<by_vote_name>,
@@ -184,6 +187,7 @@ FC_REFLECT_DERIVED( steemit::chain::witness_object, (graphene::db::object),
                     (last_aslot)(last_confirmed_block_num)(pow_worker)(signing_key)
                     (props)
                     (sbd_exchange_rate)(last_sbd_exchange_update)
+                    (last_work)
                     (running_version)
                     (hardfork_version_vote)(hardfork_time_vote)
                   )

diff --git a/libraries/chain/steem_evaluator.cpp b/libraries/chain/steem_evaluator.cpp
@@ -1172,6 +1172,16 @@ void pow_apply( database& db, Operation o ) {
 
    FC_ASSERT( db.head_block_time() > STEEMIT_MINING_TIME, "Mining cannot start until ${t}", ("t",STEEMIT_MINING_TIME) );
 
+   if( db.is_producing() || db.has_hardfork( STEEMIT_HARDFORK_0_5__59 ) )
+   {
+      const auto& witness_by_work = db.get_index_type<witness_index>().indices().get<by_work>();
+      auto work_itr = witness_by_work.find( o.work.work );
+      if( work_itr != witness_by_work.end() )
+      {
+          FC_ASSERT( !"DUPLICATE WORK DISCOVERED", "${w}  ${witness}",("w",o)("wit",*work_itr) );
+      }
+   }
+
    if( !db.has_hardfork( STEEMIT_HARDFORK_0_12__179 ) )
       FC_ASSERT( o.props.maximum_block_size >= STEEMIT_MIN_BLOCK_SIZE_LIMIT * 2 );
 
@@ -1220,6 +1230,7 @@ void pow_apply( database& db, Operation o ) {
       db.modify(*cur_witness, [&]( witness_object& w ){
           w.props             = o.props;
           w.pow_worker        = dgp.total_pow;
+          w.last_work         = o.work.work;
       });
    } else {
       db.create<witness_object>( [&]( witness_object& w )
@@ -1228,6 +1239,7 @@ void pow_apply( database& db, Operation o ) {
           w.props             = o.props;
           w.signing_key       = o.work.worker;
           w.pow_worker        = dgp.total_pow;
+          w.last_work         = o.work.work;
       });
    }
    /// POW reward depends upon whether we are before or after MINER_VOTING kicks in