Extend source and sink from DataFlow::Node instead of DataFlow::exprNode

Author: rvermeulen

java/ql/src/Security/CWE/CWE-113/ServletResponseSplitting.qll

@@ -10,23 +10,23 @@ class ServletHeaderSplittingSink extends HeaderSplittingSink {
   ServletHeaderSplittingSink() {
     exists(ResponseAddCookieMethod m, MethodAccess ma |
       ma.getMethod() = m and
-      this.getExpr() = ma.getArgument(0)
+      this.asExpr() = ma.getArgument(0)
     )
     or
     exists(ResponseAddHeaderMethod m, MethodAccess ma |
       ma.getMethod() = m and
-      this.getExpr() = ma.getAnArgument()
+      this.asExpr() = ma.getAnArgument()
     )
     or
     exists(ResponseSetHeaderMethod m, MethodAccess ma |
       ma.getMethod() = m and
-      this.getExpr() = ma.getAnArgument()
+      this.asExpr() = ma.getAnArgument()
     )
     or
     exists(JaxRsResponseBuilder builder, Method m |
       m = builder.getAMethod() and m.getName() = "header"
     |
-      this.getExpr() = m.getAReference().getArgument(1)
+      this.asExpr() = m.getAReference().getArgument(1)
     )
   }
 }

java/ql/src/semmle/code/java/security/ResponseSplitting.qll

@@ -3,9 +3,9 @@ import semmle.code.java.dataflow.DataFlow
 /**
  * Header-splitting sinks. Expressions that end up in an HTTP header.
  */
-abstract class HeaderSplittingSink extends DataFlow::ExprNode { }
+abstract class HeaderSplittingSink extends DataFlow::Node { }
 
 /**
  * Sources that cannot be used to perform a header splitting attack.
  */
-abstract class SafeHeaderSplittingSource extends DataFlow::ExprNode { }
+abstract class SafeHeaderSplittingSource extends DataFlow::Node { }