Add gas cost

rskj-core/src/main/java/org/ethereum/vm/OpCode.java

@@ -331,7 +331,7 @@ public enum OpCode {
     /**
      * (0x5e) Memory copying instruction
      */
-    MCOPY(0x5e, 3, 0, BASE_TIER),
+    MCOPY(0x5e, 3, 0, VERY_LOW_TIER),
 
     /*  Push Operations */
     /**

rskj-core/src/main/java/org/ethereum/vm/OpCodes.java

@@ -328,7 +328,7 @@ private OpCodes() {
     /**
      * (0x5e)
      */
-    static final byte OP_MCOPY = 0x5e;
+    public static final byte OP_MCOPY = 0x5e;
 
     /*  Push Operations */
     /**

rskj-core/src/main/java/org/ethereum/vm/VM.java

@@ -767,6 +767,16 @@ private long computeDataCopyGas() {
         return calcMemGas(oldMemSize, newMemSize, copySize);
     }
 
+    private long computeMemoryCopyGas() {
+        DataWord length = stack.get(stack.size() - 3);
+        DataWord offset = stack.peek();
+        long copySize = Program.limitToMaxLong(length);
+        checkSizeArgument(copySize);
+        long newMemSize = memNeeded(offset, copySize);
+        // Note: 3 additional units are added outside because of the "Very Low Tier" configuration
+        return calcMemGas(oldMemSize, newMemSize, copySize);
+    }
+
     protected void doCODESIZE() {
         if (computeGas) {
             if (op == OpCode.EXTCODESIZE) {
@@ -1438,13 +1448,7 @@ protected void doJUMPDEST()
 
     protected void doMCOPY() {
         if (computeGas) {
-            // See "Gas Cost" section on EIP 5656
-            // gas cost = 3 * (length + 31) + memory expansion cost + very low
-            long length = stack.get(stack.size() - 3).longValue();
-            long newMemSize = memNeeded(stack.peek(), length);
-            long cost = 3 * (length + 31) + calcMemGas(oldMemSize, newMemSize, 0) + 3; // TODO -> Check copy size
-
-            gasCost = GasCost.add(gasCost, cost);
+            gasCost = GasCost.add(gasCost, computeMemoryCopyGas());
             spendOpCodeGas();
         }
 

rskj-core/src/test/java/co/rsk/vm/opcode/MCopyGasTest.java

@@ -0,0 +1,98 @@
+package co.rsk.vm.opcode;
+
+import co.rsk.config.TestSystemProperties;
+import co.rsk.config.VmConfig;
+import co.rsk.peg.BridgeSupportFactory;
+import co.rsk.peg.RepositoryBtcBlockStoreWithCache;
+import co.rsk.vm.BytecodeCompiler;
+import org.ethereum.config.blockchain.upgrades.ActivationConfig;
+import org.ethereum.core.*;
+import org.ethereum.vm.DataWord;
+import org.ethereum.vm.PrecompiledContracts;
+import org.ethereum.vm.VM;
+import org.ethereum.vm.program.Program;
+import org.ethereum.vm.program.invoke.ProgramInvokeMockImpl;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+
+import java.util.HashSet;
+import java.util.stream.Stream;
+
+import static co.rsk.net.utils.TransactionUtils.createTransaction;
+import static org.ethereum.config.blockchain.upgrades.ConsensusRule.RSKIP445;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+public class MCopyGasTest {
+
+    private ActivationConfig.ForBlock activationConfig;
+
+    private final ProgramInvokeMockImpl invoke = new ProgramInvokeMockImpl();
+    private final BytecodeCompiler compiler = new BytecodeCompiler();
+    private final TestSystemProperties config = new TestSystemProperties();
+    private final VmConfig vmConfig = config.getVmConfig();
+    private final SignatureCache signatureCache = new BlockTxSignatureCache(new ReceivedTxSignatureCache());
+    private final BlockFactory blockFactory = new BlockFactory(config.getActivationConfig());
+    private final Transaction transaction = createTransaction();
+    private final PrecompiledContracts precompiledContracts = new PrecompiledContracts(
+            config,
+            new BridgeSupportFactory(
+                    new RepositoryBtcBlockStoreWithCache.Factory(
+                            config.getNetworkConstants().getBridgeConstants().getBtcParams()),
+                    config.getNetworkConstants().getBridgeConstants(),
+                    config.getActivationConfig(), signatureCache), signatureCache);
+
+    @BeforeEach
+    void setup() {
+        activationConfig = mock(ActivationConfig.ForBlock.class);
+        when(activationConfig.isActive(RSKIP445)).thenReturn(true);
+    }
+
+    @ParameterizedTest
+    @MethodSource("provideParametersForMCOPYGasTest")
+    void testMCopy_ShouldConsumeTheCorrectAmountOfGas(String[] initMemory, int dst, int src, int length, int expectedGasUsage) {
+        // Given
+        byte[] code = compiler.compile("MCOPY");
+        VM vm = new VM(vmConfig, precompiledContracts);
+
+        Program program = new Program(vmConfig, precompiledContracts, blockFactory, activationConfig, code, invoke, transaction, new HashSet<>(), new BlockTxSignatureCache(new ReceivedTxSignatureCache()));
+
+        int address = 0;
+        for (String entry : initMemory) {
+            program.memorySave(DataWord.valueOf(address), DataWord.valueFromHex(entry));
+            address += 32;
+        }
+
+        program.stackPush(DataWord.valueOf(length)); // Mind the stack order!!
+        program.stackPush(DataWord.valueOf(src));
+        program.stackPush(DataWord.valueOf(dst));
+
+        // When
+        try {
+            while (!program.isStopped()) {
+                vm.step(program);
+            }
+        } catch(Program.StackTooSmallException e) {
+            Assertions.fail("Stack too small exception");
+        }
+
+        // Then
+        Assertions.assertEquals(0, program.getStack().size());
+        Assertions.assertEquals(expectedGasUsage, program.getResult().getGasUsed());
+    }
+
+    private static Stream<Arguments> provideParametersForMCOPYGasTest() {
+        return Stream.of(
+            Arguments.of(new String[]{ "0000000000000000000000000000000000000000000000000000000000000000", "000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f" }, 0, 32, 32, 6),
+            Arguments.of(new String[]{ "0101010101010101010101010101010101010101010101010101010101010101" }, 0, 0, 32, 6),
+            Arguments.of(new String[]{ "0001020304050607080000000000000000000000000000000000000000000000" }, 0, 1, 8, 6),
+            Arguments.of(new String[]{ "0001020304050607080000000000000000000000000000000000000000000000" }, 1, 0, 8, 6),
+            Arguments.of(new String[]{ "000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f", "202122232425262728292a2b2c2d2e2f303132333435363738393a3b3c3d3e3f", "404142434445464748494a4b4c4d4e4f505152535455565758595a5b5c5d5e5f", "606162636465666768696a6b6c6d6e6f707172737475767778797a7b7c7d7e7f", "808182838485868788898a8b8c8d8e8f909192939495969798999a9b9c9d9e9f", "a0a1a2a3a4a5a6a7a8a9aaabacadaeafb0b1b2b3b4b5b6b7b8b9babbbcbdbebf", "c0c1c2c3c4c5c6c7c8c9cacbcccdcecfd0d1d2d3d4d5d6d7d8d9dadbdcdddedf", "e0e1e2e3e4e5e6e7e8e9eaebecedeeeff0f1f2f3f4f5f6f7f8f9fafbfcfdfeff" }, 256, 256, 1, 9),
+            Arguments.of(new String[]{ "000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f", "202122232425262728292a2b2c2d2e2f303132333435363738393a3b3c3d3e3f", "404142434445464748494a4b4c4d4e4f505152535455565758595a5b5c5d5e5f", "606162636465666768696a6b6c6d6e6f707172737475767778797a7b7c7d7e7f", "808182838485868788898a8b8c8d8e8f909192939495969798999a9b9c9d9e9f", "a0a1a2a3a4a5a6a7a8a9aaabacadaeafb0b1b2b3b4b5b6b7b8b9babbbcbdbebf", "c0c1c2c3c4c5c6c7c8c9cacbcccdcecfd0d1d2d3d4d5d6d7d8d9dadbdcdddedf", "e0e1e2e3e4e5e6e7e8e9eaebecedeeeff0f1f2f3f4f5f6f7f8f9fafbfcfdfeff" }, 0, 256, 256, 27)
+        );
+    }
+
+}

rskj-core/src/test/java/co/rsk/vm/opcode/MCopyInputTest.java

@@ -0,0 +1,96 @@
+package co.rsk.vm.opcode;
+
+import co.rsk.config.TestSystemProperties;
+import co.rsk.config.VmConfig;
+import co.rsk.peg.BridgeSupportFactory;
+import co.rsk.peg.RepositoryBtcBlockStoreWithCache;
+import co.rsk.vm.BytecodeCompiler;
+import org.ethereum.config.blockchain.upgrades.ActivationConfig;
+import org.ethereum.core.*;
+import org.ethereum.vm.DataWord;
+import org.ethereum.vm.PrecompiledContracts;
+import org.ethereum.vm.VM;
+import org.ethereum.vm.program.Program;
+import org.ethereum.vm.program.invoke.ProgramInvokeMockImpl;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+
+import java.util.HashSet;
+import java.util.stream.Stream;
+
+import static co.rsk.net.utils.TransactionUtils.createTransaction;
+import static org.ethereum.config.blockchain.upgrades.ConsensusRule.RSKIP445;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+public class MCopyInputTest {
+
+    private ActivationConfig.ForBlock activationConfig;
+
+    private final ProgramInvokeMockImpl invoke = new ProgramInvokeMockImpl();
+    private final BytecodeCompiler compiler = new BytecodeCompiler();
+    private final TestSystemProperties config = new TestSystemProperties();
+    private final VmConfig vmConfig = config.getVmConfig();
+    private final SignatureCache signatureCache = new BlockTxSignatureCache(new ReceivedTxSignatureCache());
+    private final BlockFactory blockFactory = new BlockFactory(config.getActivationConfig());
+    private final Transaction transaction = createTransaction();
+    private final PrecompiledContracts precompiledContracts = new PrecompiledContracts(
+            config,
+            new BridgeSupportFactory(
+                    new RepositoryBtcBlockStoreWithCache.Factory(
+                            config.getNetworkConstants().getBridgeConstants().getBtcParams()),
+                    config.getNetworkConstants().getBridgeConstants(),
+                    config.getActivationConfig(), signatureCache), signatureCache);
+
+    @BeforeEach
+    void setup() {
+        activationConfig = mock(ActivationConfig.ForBlock.class);
+        when(activationConfig.isActive(RSKIP445)).thenReturn(true);
+    }
+
+    @ParameterizedTest
+    @MethodSource("provideParametersForOOGCases")
+    void testMCopy_ShouldThrowOOGException(String[] initMemory, int dst, int src, long length) {
+        // Given
+        byte[] code = compiler.compile("MCOPY");
+        VM vm = new VM(vmConfig, precompiledContracts);
+
+        Program program = new Program(vmConfig, precompiledContracts, blockFactory, activationConfig, code, invoke, transaction, new HashSet<>(), new BlockTxSignatureCache(new ReceivedTxSignatureCache()));
+
+        int address = 0;
+        for (String entry : initMemory) {
+            program.memorySave(DataWord.valueOf(address), DataWord.valueFromHex(entry));
+            address += 32;
+        }
+
+        program.stackPush(DataWord.valueOf(length)); // Mind the stack order!!
+        program.stackPush(DataWord.valueOf(src));
+        program.stackPush(DataWord.valueOf(dst));
+
+        // Then
+        Program.OutOfGasException ex = Assertions.assertThrows(Program.OutOfGasException.class, () -> executeProgram(vm, program));
+        Assertions.assertTrue(ex.getMessage().contains("Not enough gas for 'MCOPY' operation"));
+    }
+
+    private static Stream<Arguments> provideParametersForOOGCases() {
+        return Stream.of(
+                Arguments.of(new String[]{ "0000000000000000000000000000000000000000000000000000000000000000" }, 0, 0, -1),
+                Arguments.of(new String[]{}, 0, 0, -(2 * (Long.MAX_VALUE / 3))),
+                Arguments.of(new String[]{}, 0, 0, Integer.MAX_VALUE + 1L)
+        );
+    }
+
+    private static void executeProgram(VM vm, Program program) {
+        try {
+            while (!program.isStopped()) {
+                vm.step(program);
+            }
+        } catch(Program.StackTooSmallException e) {
+            Assertions.fail("Stack too small exception");
+        }
+    }
+
+}