1  /***************************************************************************************************
  2  
  3    Zyan Disassembler Library (Zydis)
  4  
  5    Original Author : Joel Hoener
  6  
  7   * Permission is hereby granted, free of charge, to any person obtaining a copy
  8   * of this software and associated documentation files (the "Software"), to deal
  9   * in the Software without restriction, including without limitation the rights
 10   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 11   * copies of the Software, and to permit persons to whom the Software is
 12   * furnished to do so, subject to the following conditions:
 13   *
 14   * The above copyright notice and this permission notice shall be included in all
 15   * copies or substantial portions of the Software.
 16   *
 17   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 18   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 19   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 20   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 21   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 22   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 23   * SOFTWARE.
 24  
 25  ***************************************************************************************************/
 26  
 27  #include <Zydis/Disassembler.h>
 28  #include <Zycore/LibC.h>
 29  
 30  /* ============================================================================================== */
 31  /* Internal helpers                                                                               */
 32  /* ============================================================================================== */
 33  
 34  static ZyanStatus ZydisDisassemble(ZydisMachineMode machine_mode,
 35      ZyanU64 runtime_address, const void* buffer, ZyanUSize length,
 36      ZydisDisassembledInstruction *instruction, ZydisFormatterStyle style)
 37  {
 38      if (!buffer || !instruction)
 39      {
 40          return ZYAN_STATUS_INVALID_ARGUMENT;
 41      }
 42  
 43      *instruction = (ZydisDisassembledInstruction)
 44      {
 45        .runtime_address = runtime_address
 46      };
 47  
 48      // Derive the stack width from the address width.
 49      ZydisStackWidth stack_width;
 50      switch (machine_mode)
 51      {
 52      case ZYDIS_MACHINE_MODE_LONG_64:
 53          stack_width = ZYDIS_STACK_WIDTH_64;
 54          break;
 55      case ZYDIS_MACHINE_MODE_LONG_COMPAT_32:
 56      case ZYDIS_MACHINE_MODE_LEGACY_32:
 57          stack_width = ZYDIS_STACK_WIDTH_32;
 58          break;
 59      case ZYDIS_MACHINE_MODE_LONG_COMPAT_16:
 60      case ZYDIS_MACHINE_MODE_LEGACY_16:
 61      case ZYDIS_MACHINE_MODE_REAL_16:
 62          stack_width = ZYDIS_STACK_WIDTH_16;
 63          break;
 64      default:
 65          return ZYAN_STATUS_INVALID_ARGUMENT;
 66      }
 67  
 68      ZydisDecoder decoder;
 69      ZYAN_CHECK(ZydisDecoderInit(&decoder, machine_mode, stack_width));
 70  
 71      ZydisDecoderContext ctx;
 72      ZYAN_CHECK(ZydisDecoderDecodeInstruction(&decoder, &ctx, buffer, length, &instruction->info));
 73      ZYAN_CHECK(ZydisDecoderDecodeOperands(&decoder, &ctx, &instruction->info,
 74          instruction->operands, instruction->info.operand_count));
 75  
 76      ZydisFormatter formatter;
 77      ZYAN_CHECK(ZydisFormatterInit(&formatter, style));
 78      ZYAN_CHECK(ZydisFormatterFormatInstruction(&formatter, &instruction->info,
 79          instruction->operands, instruction->info.operand_count_visible, instruction->text,
 80          sizeof(instruction->text), runtime_address, ZYAN_NULL));
 81  
 82      return ZYAN_STATUS_SUCCESS;
 83  }
 84  
 85  /* ============================================================================================== */
 86  /* Public functions                                                                               */
 87  /* ============================================================================================== */
 88  
 89  ZyanStatus ZydisDisassembleIntel(ZydisMachineMode machine_mode,
 90      ZyanU64 runtime_address, const void* buffer, ZyanUSize length,
 91      ZydisDisassembledInstruction *instruction)
 92  {
 93      return ZydisDisassemble(machine_mode, runtime_address, buffer, length, instruction,
 94          ZYDIS_FORMATTER_STYLE_INTEL);
 95  }
 96  
 97  ZyanStatus ZydisDisassembleATT(ZydisMachineMode machine_mode,
 98      ZyanU64 runtime_address, const void* buffer, ZyanUSize length,
 99      ZydisDisassembledInstruction *instruction)
100  {
101      return ZydisDisassemble(machine_mode, runtime_address, buffer, length, instruction,
102          ZYDIS_FORMATTER_STYLE_ATT);
103  }
104  
105  /* ============================================================================================== */