craw/exception_handler.cpp

   1 #include <iostream>
   2 #include <windows.h>
   3 #include <boost/thread/mutex.hpp>
   4 #include <ail/string.hpp>
   5 #include <ail/types.hpp>
   6 #include "exception_handler.hpp"
   7 #include "utility.hpp"
   8 #include "patch.hpp"
   9 #include "interceptor.hpp"
  10 #include "arguments.hpp"
  11 #include "debug_registers.hpp"
  12
  13 typedef std::map<DWORD, debug_register_vector> thread_id_map_type;
  14
  15 namespace
  16 {
  17         thread_id_map_type thread_id_map;
  18         boost::mutex thread_id_map_mutex;
  19 }
  20
  21 void add_debug_register_manipulation_entry(DWORD thread_id, debug_register_vector const & data)
  22 {
  23         boost::mutex::scoped_lock lock(thread_id_map_mutex);
  24         thread_id_map[thread_id] = data;
  25 }
  26
  27 bool process_breakpoint(CONTEXT & thread_context)
  28 {
  29         boost::mutex::scoped_lock lock(thread_id_map_mutex);
  30         DWORD thread_id = GetCurrentThreadId();
  31         thread_id_map_type::iterator iterator = thread_id_map.find(thread_id);
  32         if(iterator == thread_id_map.end())
  33                 return false;
  34
  35         debug_register_vector & data = iterator->second;
  36
  37         thread_context.ContextFlags = CONTEXT_FULL | CONTEXT_DEBUG_REGISTERS;
  38         set_debug_registers(thread_context, data);
  39
  40         thread_context.Eip++;
  41
  42         return true;
  43 }
  44
  45 void set_own_context(debug_register_vector const & data)
  46 {
  47         add_debug_register_manipulation_entry(GetCurrentThreadId(), data);
  48         //write_line("set_own_context: " + ail::hex_string_32(reinterpret_cast<unsigned>(&set_own_context)));
  49         __asm
  50         {
  51                 int 3
  52         }
  53 }
  54
  55 LONG WINAPI vectored_exception_handler(PEXCEPTION_POINTERS ExceptionInfo)
  56 {
  57         //nasty
  58         DWORD const DBG_PRINTEXCEPTION_C = 0x40010006;
  59
  60         EXCEPTION_RECORD & exception_record = *(ExceptionInfo->ExceptionRecord);
  61         CONTEXT & thread_context = *(ExceptionInfo->ContextRecord);
  62
  63         //write_line("Exception type " + ail::hex_string_32(exception_record.ExceptionCode) + " at " + ail::hex_string_32(thread_context.Eip) + " in thread " + ail::hex_string_32(GetCurrentThreadId()));
  64
  65         switch(exception_record.ExceptionCode)
  66         {
  67         case EXCEPTION_BREAKPOINT:
  68                 if(process_breakpoint(thread_context))
  69                         return EXCEPTION_CONTINUE_EXECUTION;
  70                 break;
  71
  72         case EXCEPTION_SINGLE_STEP:
  73                 perform_debug_register_check(thread_context);
  74                 return EXCEPTION_CONTINUE_EXECUTION;
  75
  76         case DBG_PRINTEXCEPTION_C:
  77                 if(verbose)
  78                         write_line("Debug message");
  79                 break;
  80         }
  81
  82         return EXCEPTION_CONTINUE_SEARCH;
  83 }
  84
  85 bool install_exception_handler()
  86 {
  87         if(!AddVectoredExceptionHandler(0, &vectored_exception_handler))
  88         {
  89                 error("Failed to add vectored exception handler: " + ail::hex_string_32(GetLastError()));
  90                 return false;
  91         }
  92         return true;
  93 }