Add a sample on memoryBP + singlestep (cc Heurs :D)

samples/debugger_membp_singlestep.py

@@ -0,0 +1,63 @@
+import sys
+import os.path
+import pprint
+sys.path.append(os.path.abspath(__file__ + "\..\.."))
+
+import windows
+import windows.test
+import windows.debug
+
+import windows.native_exec.simple_x86 as x86
+from windows.generated_def.winstructs import *
+
+
+
+class MyDebugger(windows.debug.Debugger):
+    def __init__(self, *args, **kwargs):
+        super(MyDebugger, self).__init__(*args, **kwargs)
+        self.single_step_counter = 0
+
+    def on_exception(self, exception):
+        code = exception.ExceptionRecord.ExceptionCode
+        addr = exception.ExceptionRecord.ExceptionAddress
+        print("Got exception {0} at 0x{1:x}".format(code, addr))
+
+    def on_single_step(self, exception):
+        code = exception.ExceptionRecord.ExceptionCode
+        addr = exception.ExceptionRecord.ExceptionAddress
+        print("Got single_step {0} at 0x{1:x}".format(code, addr))
+        self.single_step_counter -= 1
+        if self.single_step_counter > 0:
+            return self.single_step()
+
+
+class SingleStepOnWrite(windows.debug.MemoryBreakpoint):
+    DEFAULT_PROTECT = PAGE_READONLY
+    """Check that BP/dbg can trigger single step and that instruction follows"""
+    def trigger(self, dbg, exc):
+        fault_addr = exc.ExceptionRecord.ExceptionInformation[1]
+        eip = dbg.current_thread.context.pc
+        print("Instruction at <{0:#x}> wrote at <{1:#x}>".format(eip, fault_addr))
+        dbg.single_step_counter = 4
+        return dbg.single_step()
+
+calc = windows.test.pop_calc_32(dwCreationFlags=DEBUG_PROCESS)
+d = MyDebugger(calc)
+
+code = calc.virtual_alloc(0x1000)
+data = calc.virtual_alloc(0x1000)
+
+injected = x86.MultipleInstr()
+injected += x86.Mov("EAX", 0)
+injected += x86.Mov(x86.deref(data), "EAX")
+injected += x86.Add("EAX", 4)
+injected += x86.Mov(x86.deref(data + 4), "EAX")
+injected += x86.Nop()
+injected += x86.Nop()
+injected += x86.Ret()
+
+calc.write_memory(code, injected.get_code())
+d.add_bp(SingleStepOnWrite(data, size=0x1000))
+calc.create_thread(code, 0)
+d.loop()
+