Add support for C++ style casts. (#177)

ShiftLeftSecurity · Jan 30, 2020 · ccf6240 · ccf6240
1 parent 12a6440
commit ccf6240
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Showing 3 changed files with 100 additions and 6 deletions.
diff --git a/src/main/antlr4/io/shiftleft/fuzzyc2cpg/Common.g4 b/src/main/antlr4/io/shiftleft/fuzzyc2cpg/Common.g4
@@ -152,7 +152,10 @@ shift_expression: additive_expression ( ('<<'|'>>') shift_expression)?;
 additive_expression: multiplicative_expression (('+'| '-') additive_expression)?;
 multiplicative_expression: cast_expression ( ('*'| '/'| '%') multiplicative_expression)?;
 
+cpp_cast_identifier: 'const_cast' | 'static_cast' | 'dynamic_cast' | 'reinterpret_cast';
+
 cast_expression: ('(' cast_target ')' cast_expression)
+ | cpp_cast_identifier '<' cast_target '>' '(' cast_expression ')'
  | unary_expression
 ;
 

diff --git a/src/test/java/io/shiftleft/fuzzyc2cpg/antlrparsers/functionparser/FunctionParserTest.java b/src/test/java/io/shiftleft/fuzzyc2cpg/antlrparsers/functionparser/FunctionParserTest.java
@@ -99,4 +99,36 @@ public void testArrayDelete() {
  assertEquals("(statements (statement (expr_statement (expr (assign_expr (conditional_expression (or_expression (and_expression (inclusive_or_expression (exclusive_or_expression (bit_and_expression (equality_expression (relational_expression (shift_expression (additive_expression (multiplicative_expression (cast_expression (unary_expression (delete_expression delete [ ] (identifier n))))))))))))))))) ;)))",
  output);
  }
+
+ @Test
+ public void testCPPConstCast() {
+ String input = "int x = const_cast<int>(n);";
+ String output = generateParserOutput(input);
+ assertEquals("(statements (statement (simple_decl (var_decl (type_name (base_type int)) (init_declarator_list (init_declarator (declarator (identifier x)) = (initializer (assign_expr (conditional_expression (or_expression (and_expression (inclusive_or_expression (exclusive_or_expression (bit_and_expression (equality_expression (relational_expression (shift_expression (additive_expression (multiplicative_expression (cast_expression (cpp_cast_identifier const_cast) < (cast_target (type_name (base_type int))) > ( (cast_expression (unary_expression (postfix_expression (primary_expression (identifier n))))) )))))))))))))))) ;)))))",
+ output);
+ }
+
+ @Test
+ public void testCPPStaticCast() {
+ String input = "int x = static_cast<int>(n);";
+ String output = generateParserOutput(input);
+ assertEquals("(statements (statement (simple_decl (var_decl (type_name (base_type int)) (init_declarator_list (init_declarator (declarator (identifier x)) = (initializer (assign_expr (conditional_expression (or_expression (and_expression (inclusive_or_expression (exclusive_or_expression (bit_and_expression (equality_expression (relational_expression (shift_expression (additive_expression (multiplicative_expression (cast_expression (cpp_cast_identifier static_cast) < (cast_target (type_name (base_type int))) > ( (cast_expression (unary_expression (postfix_expression (primary_expression (identifier n))))) )))))))))))))))) ;)))))",
+ output);
+ }
+
+ @Test
+ public void testCPPDynamicCast() {
+ String input = "int x = dynamic_cast<int>(n);";
+ String output = generateParserOutput(input);
+ assertEquals("(statements (statement (simple_decl (var_decl (type_name (base_type int)) (init_declarator_list (init_declarator (declarator (identifier x)) = (initializer (assign_expr (conditional_expression (or_expression (and_expression (inclusive_or_expression (exclusive_or_expression (bit_and_expression (equality_expression (relational_expression (shift_expression (additive_expression (multiplicative_expression (cast_expression (cpp_cast_identifier dynamic_cast) < (cast_target (type_name (base_type int))) > ( (cast_expression (unary_expression (postfix_expression (primary_expression (identifier n))))) )))))))))))))))) ;)))))",
+ output);
+ }
+
+ @Test
+ public void testCPPReinterpretCast() {
+ String input = "int x = reinterpret_cast<int>(n);";
+ String output = generateParserOutput(input);
+ assertEquals("(statements (statement (simple_decl (var_decl (type_name (base_type int)) (init_declarator_list (init_declarator (declarator (identifier x)) = (initializer (assign_expr (conditional_expression (or_expression (and_expression (inclusive_or_expression (exclusive_or_expression (bit_and_expression (equality_expression (relational_expression (shift_expression (additive_expression (multiplicative_expression (cast_expression (cpp_cast_identifier reinterpret_cast) < (cast_target (type_name (base_type int))) > ( (cast_expression (unary_expression (postfix_expression (primary_expression (identifier n))))) )))))))))))))))) ;)))))",
+ output);
+ }
 }
diff --git a/src/test/scala/io/shiftleft/fuzzyc2cpg/astnew/AstToCpgTests.scala b/src/test/scala/io/shiftleft/fuzzyc2cpg/astnew/AstToCpgTests.scala
@@ -1,9 +1,11 @@
 package io.shiftleft.fuzzyc2cpg.astnew
 
-import java.util.prefs.NodeChangeListener
-
 import gremlin.scala._
-import io.shiftleft.codepropertygraph.generated.{EdgeTypes, NodeKeyNames, NodeKeys, NodeTypes, Operators}
+import org.antlr.v4.runtime.{CharStreams, ParserRuleContext}
+import org.apache.tinkerpop.gremlin.tinkergraph.structure.TinkerGraph
+import org.scalatest.{Matchers, WordSpec}
+
+import io.shiftleft.codepropertygraph.generated.{EdgeTypes, NodeKeys, NodeTypes, Operators}
 import io.shiftleft.fuzzyc2cpg.ModuleLexer
 import io.shiftleft.fuzzyc2cpg.adapter.CpgAdapter
 import io.shiftleft.fuzzyc2cpg.adapter.EdgeKind.EdgeKind
@@ -13,9 +15,6 @@ import io.shiftleft.fuzzyc2cpg.adapter.NodeProperty.NodeProperty
 import io.shiftleft.fuzzyc2cpg.ast.{AstNode, AstNodeBuilder}
 import io.shiftleft.fuzzyc2cpg.parser.modules.AntlrCModuleParserDriver
 import io.shiftleft.fuzzyc2cpg.parser.{AntlrParserDriverObserver, TokenSubStream}
-import org.antlr.v4.runtime.{CharStreams, ParserRuleContext}
-import org.apache.tinkerpop.gremlin.tinkergraph.structure.TinkerGraph
-import org.scalatest.{Matchers, WordSpec}
 
 class AstToCpgTests extends WordSpec with Matchers {
 
@@ -1001,6 +1000,66 @@ class AstToCpgTests extends WordSpec with Matchers {
  val callArgs = call.expandArgument
  callArgs.check(1, x => x.value2[String](NodeKeys.CODE), "n")
  }
+
+ "be correct for const_cast" in new Fixture(
+ """
+ |void foo() {
+ | int y = const_cast<int>(n);
+ | return;
+ |}
+ |""".stripMargin
+ ) {
+ val call = getCall("<operator>.cast")
+ call.checkForSingle(NodeKeys.CODE, "const_cast<int>(n)")
+
+ val callArgs = call.expandArgument
+ callArgs.check(2, x => x.value2(NodeKeys.CODE), "int", "n")
+ }
+
+ "be correct for static_cast" in new Fixture(
+ """
+ |void foo() {
+ | int y = static_cast<int>(n);
+ | return;
+ |}
+ |""".stripMargin
+ ) {
+ val call = getCall("<operator>.cast")
+ call.checkForSingle(NodeKeys.CODE, "static_cast<int>(n)")
+
+ val callArgs = call.expandArgument
+ callArgs.check(2, x => x.value2(NodeKeys.CODE), "int", "n")
+ }
+
+ "be correct for dynamic_cast" in new Fixture(
+ """
+ |void foo() {
+ | int y = dynamic_cast<int>(n);
+ | return;
+ |}
+ |""".stripMargin
+ ) {
+ val call = getCall("<operator>.cast")
+ call.checkForSingle(NodeKeys.CODE, "dynamic_cast<int>(n)")
+
+ val callArgs = call.expandArgument
+ callArgs.check(2, x => x.value2(NodeKeys.CODE), "int", "n")
+ }
+
+ "be correct for reinterpret_cast" in new Fixture(
+ """
+ |void foo() {
+ | int y = reinterpret_cast<int>(n);
+ | return;
+ |}
+ |""".stripMargin
+ ) {
+ val call = getCall("<operator>.cast")
+ call.checkForSingle(NodeKeys.CODE, "reinterpret_cast<int>(n)")
+
+ val callArgs = call.expandArgument
+ callArgs.check(2, x => x.value2(NodeKeys.CODE), "int", "n")
+ }
  }
 
  "AST" should {