@Override
public void visitClassContext(ClassContext classContext) {
JavaClass javaClass = classContext.getJavaClass();
Method[] methodList = javaClass.getMethods();
for (Method m : methodList) {
MethodGen methodGen = classContext.getMethodGen(m);
if (DEBUG) {
System.out.println(">>> Method: " + m.getName());
}
// To suspect that an invalid String representation is being build,
// we identify the construction of a MessageDigest and
// the use of a function that trim leading 0.
boolean invokeMessageDigest = false;
boolean invokeToHexString = false;
ConstantPoolGen cpg = classContext.getConstantPoolGen();
if (methodGen == null || methodGen.getInstructionList() == null) {
continue; // No instruction .. nothing to do
}
for (Iterator itIns = methodGen.getInstructionList().iterator(); itIns.hasNext(); ) {
Instruction inst = ((InstructionHandle) itIns.next()).getInstruction();
if (DEBUG) {
ByteCode.printOpCode(inst, cpg);
}
if (inst instanceof INVOKEVIRTUAL) { // MessageDigest.digest is called
INVOKEVIRTUAL invoke = (INVOKEVIRTUAL) inst;
if ("java.security.MessageDigest".equals(invoke.getClassName(cpg))
&& "digest".equals(invoke.getMethodName(cpg))) {
invokeMessageDigest = true;
}
} else if (inst instanceof INVOKESTATIC
&& invokeMessageDigest) { // The conversion must occurs after the digest was created
INVOKESTATIC invoke = (INVOKESTATIC) inst;
if ("java.lang.Integer".equals(invoke.getClassName(cpg))
&& "toHexString".equals(invoke.getMethodName(cpg))) {
invokeToHexString = true;
}
}
}
if (invokeMessageDigest && invokeToHexString) {
bugReporter.reportBug(
new BugInstance(this, BAD_HEXA_CONVERSION_TYPE, Priorities.NORMAL_PRIORITY) //
.addClassAndMethod(javaClass, m));
}
}
}
public static String getCallClassName(Instruction ins, ConstantPoolGen cp) {
if (ins instanceof INVOKESTATIC) {
INVOKESTATIC invst = (INVOKESTATIC) ins;
return invst.getClassName(cp);
} else if (ins instanceof INVOKEVIRTUAL) {
INVOKEVIRTUAL invst = (INVOKEVIRTUAL) ins;
return invst.getClassName(cp);
} else if (ins instanceof INVOKEINTERFACE) {
INVOKEINTERFACE invst = (INVOKEINTERFACE) ins;
return invst.getClassName(cp);
} else if (ins instanceof INVOKESPECIAL) {
INVOKESPECIAL invst = (INVOKESPECIAL) ins;
return invst.getClassName(cp);
} else {
return null;
}
}
public static Type[] getCallArgTypes(Instruction ins, ConstantPoolGen cp) {
if (ins instanceof INVOKESTATIC) {
INVOKESTATIC invst = (INVOKESTATIC) ins;
return invst.getArgumentTypes(cp);
} else if (ins instanceof INVOKEVIRTUAL) {
INVOKEVIRTUAL invst = (INVOKEVIRTUAL) ins;
return invst.getArgumentTypes(cp);
} else if (ins instanceof INVOKEINTERFACE) {
INVOKEINTERFACE invst = (INVOKEINTERFACE) ins;
return invst.getArgumentTypes(cp);
} else if (ins instanceof INVOKESPECIAL) {
INVOKESPECIAL invst = (INVOKESPECIAL) ins;
return invst.getArgumentTypes(cp);
} else {
return null;
}
}
/** Symbolically executes the corresponding Java Virtual Machine instruction. */
public void visitINVOKEVIRTUAL(INVOKEVIRTUAL o) {
stack().pop(); // objectref
for (int i = 0; i < o.getArgumentTypes(cpg).length; i++) {
stack().pop();
}
// We are sure the invoked method will xRETURN eventually
// We simulate xRETURNs functionality here because we
// don't really "jump into" and simulate the invoked
// method.
if (o.getReturnType(cpg) != Type.VOID) {
Type t = o.getReturnType(cpg);
if (t.equals(Type.BOOLEAN)
|| t.equals(Type.CHAR)
|| t.equals(Type.BYTE)
|| t.equals(Type.SHORT)) {
t = Type.INT;
}
stack().push(t);
}
}
public static Instruction getNewInvoke(Instruction ins, int index) {
if (ins instanceof INVOKESTATIC) {
INVOKESTATIC invst = (INVOKESTATIC) ins;
invst.setIndex(index);
return invst;
} else if (ins instanceof INVOKEVIRTUAL) {
INVOKEVIRTUAL invst = (INVOKEVIRTUAL) ins;
invst.setIndex(index);
return invst;
} else if (ins instanceof INVOKEINTERFACE) {
INVOKEINTERFACE invst = (INVOKEINTERFACE) ins;
invst.setIndex(index);
return invst;
} else if (ins instanceof INVOKESPECIAL) {
INVOKESPECIAL invst = (INVOKESPECIAL) ins;
invst.setIndex(index);
return invst;
} else {
return null;
}
}
/**
* Transforms invoke instructions that match the specified list for this class to call the
* specified static call instead.
*/
private InstructionList xform_inst(MethodGen mg, Instruction inst) {
switch (inst.getOpcode()) {
case Constants.INVOKESTATIC:
{
InstructionList il = new InstructionList();
INVOKESTATIC is = (INVOKESTATIC) inst;
String cname = is.getClassName(pgen);
String mname = is.getMethodName(pgen);
Type[] args = is.getArgumentTypes(pgen);
MethodDef orig = new MethodDef(cname + "." + mname, args);
MethodInfo call = method_map.get(orig);
if (call != null) {
call.cnt++;
String classname = call.method_class;
String methodname = mname;
debug_map.log(
"%s.%s: Replacing method %s.%s (%s) with %s.%s%n",
mg.getClassName(),
mg.getName(),
cname,
mname,
UtilMDE.join(args, ", "),
classname,
methodname);
il.append(
ifact.createInvoke(
classname, methodname, is.getReturnType(pgen), args, Constants.INVOKESTATIC));
}
return (il);
}
case Constants.INVOKEVIRTUAL:
{
InstructionList il = new InstructionList();
INVOKEVIRTUAL iv = (INVOKEVIRTUAL) inst;
String cname = iv.getClassName(pgen);
String mname = iv.getMethodName(pgen);
Type[] args = iv.getArgumentTypes(pgen);
Type instance_type = iv.getReferenceType(pgen);
Type[] new_args = BCELUtil.insert_type(instance_type, args);
MethodDef orig = new MethodDef(cname + "." + mname, args);
if (debug_class) System.out.printf("looking for %s in map %s%n", orig, method_map);
MethodInfo call = method_map.get(orig);
if (call != null) {
call.cnt++;
String classname = call.method_class;
String methodname = mname;
debug_map.log(
"Replacing method %s.%s (%s) with %s.%s%n",
cname, mname, ArraysMDE.toString(args), classname, methodname);
il.append(
ifact.createInvoke(
classname,
methodname,
iv.getReturnType(pgen),
new_args,
Constants.INVOKESTATIC));
}
return (il);
}
default:
return (null);
}
}
