/*************************************************************************************************** Zyan Disassembler Library (Zydis) Original Author : Florian Bernd * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in all * copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. ***************************************************************************************************/ #include "zydis/Zycore/LibC.h" #include "zydis/Zydis/Segment.h" /* ============================================================================================== */ /* Exported functions */ /* ============================================================================================== */ ZyanStatus ZydisGetInstructionSegments(const ZydisDecodedInstruction* instruction, ZydisInstructionSegments* segments) { if (!instruction || !segments) { return ZYAN_STATUS_INVALID_ARGUMENT; } ZYAN_MEMSET(segments, 0, sizeof(*segments)); // Legacy prefixes and `REX` if (instruction->raw.prefix_count) { const ZyanU8 rex_offset = (instruction->attributes & ZYDIS_ATTRIB_HAS_REX) ? 1 : 0; if (!rex_offset || (instruction->raw.prefix_count > 1)) { segments->segments[segments->count ].type = ZYDIS_INSTR_SEGMENT_PREFIXES; segments->segments[segments->count ].offset = 0; segments->segments[segments->count++].size = instruction->raw.prefix_count - rex_offset; } if (rex_offset) { segments->segments[segments->count ].type = ZYDIS_INSTR_SEGMENT_REX; segments->segments[segments->count ].offset = instruction->raw.prefix_count - rex_offset; segments->segments[segments->count++].size = 1; } } // Encoding prefixes ZydisInstructionSegment segment_type = ZYDIS_INSTR_SEGMENT_NONE; ZyanU8 segment_offset = 0; ZyanU8 segment_size = 0; switch (instruction->encoding) { case ZYDIS_INSTRUCTION_ENCODING_XOP: segment_type = ZYDIS_INSTR_SEGMENT_XOP; segment_offset = instruction->raw.xop.offset; segment_size = 3; break; case ZYDIS_INSTRUCTION_ENCODING_VEX: segment_type = ZYDIS_INSTR_SEGMENT_VEX; segment_offset = instruction->raw.vex.offset; segment_size = instruction->raw.vex.size; break; case ZYDIS_INSTRUCTION_ENCODING_EVEX: segment_type = ZYDIS_INSTR_SEGMENT_EVEX; segment_offset = instruction->raw.evex.offset; segment_size = 4; break; case ZYDIS_INSTRUCTION_ENCODING_MVEX: segment_type = ZYDIS_INSTR_SEGMENT_MVEX; segment_offset = instruction->raw.mvex.offset; segment_size = 4; break; default: break; } if (segment_type) { segments->segments[segments->count ].type = segment_type; segments->segments[segments->count ].offset = segment_offset; segments->segments[segments->count++].size = segment_size; } // Opcode segment_size = 1; if ((instruction->encoding == ZYDIS_INSTRUCTION_ENCODING_LEGACY) || (instruction->encoding == ZYDIS_INSTRUCTION_ENCODING_3DNOW)) { switch (instruction->opcode_map) { case ZYDIS_OPCODE_MAP_DEFAULT: break; case ZYDIS_OPCODE_MAP_0F: ZYAN_FALLTHROUGH; case ZYDIS_OPCODE_MAP_0F0F: segment_size = 2; break; case ZYDIS_OPCODE_MAP_0F38: ZYAN_FALLTHROUGH; case ZYDIS_OPCODE_MAP_0F3A: segment_size = 3; break; default: ZYAN_UNREACHABLE; } } segments->segments[segments->count ].type = ZYDIS_INSTR_SEGMENT_OPCODE; if (segments->count) { segments->segments[segments->count].offset = segments->segments[segments->count - 1].offset + segments->segments[segments->count - 1].size; } else { segments->segments[segments->count].offset = 0; } segments->segments[segments->count++].size = segment_size; // ModRM if (instruction->attributes & ZYDIS_ATTRIB_HAS_MODRM) { segments->segments[segments->count ].type = ZYDIS_INSTR_SEGMENT_MODRM; segments->segments[segments->count ].offset = instruction->raw.modrm.offset; segments->segments[segments->count++].size = 1; } // SIB if (instruction->attributes & ZYDIS_ATTRIB_HAS_SIB) { segments->segments[segments->count ].type = ZYDIS_INSTR_SEGMENT_SIB; segments->segments[segments->count ].offset = instruction->raw.sib.offset; segments->segments[segments->count++].size = 1; } // Displacement if (instruction->raw.disp.size) { segments->segments[segments->count ].type = ZYDIS_INSTR_SEGMENT_DISPLACEMENT; segments->segments[segments->count ].offset = instruction->raw.disp.offset; segments->segments[segments->count++].size = instruction->raw.disp.size / 8; } // Immediates for (ZyanU8 i = 0; i < 2; ++i) { if (instruction->raw.imm[i].size) { segments->segments[segments->count ].type = ZYDIS_INSTR_SEGMENT_IMMEDIATE; segments->segments[segments->count ].offset = instruction->raw.imm[i].offset; segments->segments[segments->count++].size = instruction->raw.imm[i].size / 8; } } if (instruction->encoding == ZYDIS_INSTRUCTION_ENCODING_3DNOW) { segments->segments[segments->count].type = ZYDIS_INSTR_SEGMENT_OPCODE; segments->segments[segments->count].offset = instruction->length -1; segments->segments[segments->count++].size = 1; } return ZYAN_STATUS_SUCCESS; } /* ---------------------------------------------------------------------------------------------- */ /* ============================================================================================== */