diff options
Diffstat (limited to 'js/src/zydis/Zydis/Encoder.h')
| -rw-r--r-- | js/src/zydis/Zydis/Encoder.h | 460 |
1 files changed, 460 insertions, 0 deletions
diff --git a/js/src/zydis/Zydis/Encoder.h b/js/src/zydis/Zydis/Encoder.h new file mode 100644 index 0000000000..9b0b8d662e --- /dev/null +++ b/js/src/zydis/Zydis/Encoder.h @@ -0,0 +1,460 @@ +/*************************************************************************************************** + + Zyan Disassembler Library (Zydis) + + Original Author : Mappa + + * 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. + +***************************************************************************************************/ + +/** + * @file + * Functions for encoding instructions. + */ + +#ifndef ZYDIS_ENCODER_H +#define ZYDIS_ENCODER_H + +#include "zydis/Zycore/Types.h" +#include "zydis/Zydis/MetaInfo.h" +#include "zydis/Zydis/Register.h" +#include "zydis/Zydis/DecoderTypes.h" +#include "zydis/Zydis/Mnemonic.h" +#include "zydis/Zydis/Status.h" + +#ifdef __cplusplus +extern "C" { +#endif + +/* ============================================================================================== */ +/* Macros */ +/* ============================================================================================== */ + +/* ---------------------------------------------------------------------------------------------- */ +/* Constants */ +/* ---------------------------------------------------------------------------------------------- */ + +/** + * Maximum number of encodable (explicit and implicit) operands + */ +#define ZYDIS_ENCODER_MAX_OPERANDS 5 + +// If asserts are failing here remember to update encoder table generator before fixing asserts +ZYAN_STATIC_ASSERT(ZYAN_BITS_TO_REPRESENT(ZYDIS_ENCODER_MAX_OPERANDS) == 3); + +/** + * Combination of all user-encodable prefixes + */ +#define ZYDIS_ENCODABLE_PREFIXES (ZYDIS_ATTRIB_HAS_LOCK | \ + ZYDIS_ATTRIB_HAS_REP | \ + ZYDIS_ATTRIB_HAS_REPE | \ + ZYDIS_ATTRIB_HAS_REPNE | \ + ZYDIS_ATTRIB_HAS_BND | \ + ZYDIS_ATTRIB_HAS_XACQUIRE | \ + ZYDIS_ATTRIB_HAS_XRELEASE | \ + ZYDIS_ATTRIB_HAS_BRANCH_NOT_TAKEN | \ + ZYDIS_ATTRIB_HAS_BRANCH_TAKEN | \ + ZYDIS_ATTRIB_HAS_NOTRACK | \ + ZYDIS_ATTRIB_HAS_SEGMENT_CS | \ + ZYDIS_ATTRIB_HAS_SEGMENT_SS | \ + ZYDIS_ATTRIB_HAS_SEGMENT_DS | \ + ZYDIS_ATTRIB_HAS_SEGMENT_ES | \ + ZYDIS_ATTRIB_HAS_SEGMENT_FS | \ + ZYDIS_ATTRIB_HAS_SEGMENT_GS) + +/* ---------------------------------------------------------------------------------------------- */ + +/* ============================================================================================== */ +/* Enums and types */ +/* ============================================================================================== */ + +/** + * Defines possible physical instruction encodings as bit flags, so multiple acceptable encodings + * can be specified simultaneously. + */ +typedef enum ZydisEncodableEncoding_ +{ + ZYDIS_ENCODABLE_ENCODING_DEFAULT = 0x00000000, + ZYDIS_ENCODABLE_ENCODING_LEGACY = 0x00000001, + ZYDIS_ENCODABLE_ENCODING_3DNOW = 0x00000002, + ZYDIS_ENCODABLE_ENCODING_XOP = 0x00000004, + ZYDIS_ENCODABLE_ENCODING_VEX = 0x00000008, + ZYDIS_ENCODABLE_ENCODING_EVEX = 0x00000010, + ZYDIS_ENCODABLE_ENCODING_MVEX = 0x00000020, + + /** + * Maximum value of this enum. + */ + ZYDIS_ENCODABLE_ENCODING_MAX_VALUE = (ZYDIS_ENCODABLE_ENCODING_MVEX | + (ZYDIS_ENCODABLE_ENCODING_MVEX - 1)), + /** + * The minimum number of bits required to represent all values of this enum. + */ + ZYDIS_ENCODABLE_ENCODING_REQUIRED_BITS = + ZYAN_BITS_TO_REPRESENT(ZYDIS_ENCODABLE_ENCODING_MAX_VALUE) +} ZydisEncodableEncoding; + +/** + * Defines encodable physical/effective sizes of relative immediate operands. See + * `ZydisEncoderRequest.branch_width` for more details. + */ +typedef enum ZydisBranchWidth_ +{ + ZYDIS_BRANCH_WIDTH_NONE, + ZYDIS_BRANCH_WIDTH_8, + ZYDIS_BRANCH_WIDTH_16, + ZYDIS_BRANCH_WIDTH_32, + ZYDIS_BRANCH_WIDTH_64, + + /** + * Maximum value of this enum. + */ + ZYDIS_BRANCH_WIDTH_MAX_VALUE = ZYDIS_BRANCH_WIDTH_64, + /** + * The minimum number of bits required to represent all values of this enum. + */ + ZYDIS_BRANCH_WIDTH_REQUIRED_BITS = ZYAN_BITS_TO_REPRESENT(ZYDIS_BRANCH_WIDTH_MAX_VALUE) +} ZydisBranchWidth; + +/** + * Defines possible values for address size hints. See `ZydisEncoderRequest` for more information + * about address size hints. + */ +typedef enum ZydisAddressSizeHint_ +{ + ZYDIS_ADDRESS_SIZE_HINT_NONE, + ZYDIS_ADDRESS_SIZE_HINT_16, + ZYDIS_ADDRESS_SIZE_HINT_32, + ZYDIS_ADDRESS_SIZE_HINT_64, + + /** + * Maximum value of this enum. + */ + ZYDIS_ADDRESS_SIZE_HINT_MAX_VALUE = ZYDIS_ADDRESS_SIZE_HINT_64, + /** + * The minimum number of bits required to represent all values of this enum. + */ + ZYDIS_ADDRESS_SIZE_HINT_REQUIRED_BITS = + ZYAN_BITS_TO_REPRESENT(ZYDIS_ADDRESS_SIZE_HINT_MAX_VALUE) +} ZydisAddressSizeHint; + +/** + * Defines possible values for operand size hints. See `ZydisEncoderRequest` for more information + * about operand size hints. + */ +typedef enum ZydisOperandSizeHint_ +{ + ZYDIS_OPERAND_SIZE_HINT_NONE, + ZYDIS_OPERAND_SIZE_HINT_8, + ZYDIS_OPERAND_SIZE_HINT_16, + ZYDIS_OPERAND_SIZE_HINT_32, + ZYDIS_OPERAND_SIZE_HINT_64, + + /** + * Maximum value of this enum. + */ + ZYDIS_OPERAND_SIZE_HINT_MAX_VALUE = ZYDIS_OPERAND_SIZE_HINT_64, + /** + * The minimum number of bits required to represent all values of this enum. + */ + ZYDIS_OPERAND_SIZE_HINT_REQUIRED_BITS = + ZYAN_BITS_TO_REPRESENT(ZYDIS_OPERAND_SIZE_HINT_MAX_VALUE) +} ZydisOperandSizeHint; + +/** + * Describes explicit or implicit instruction operand. + */ +typedef struct ZydisEncoderOperand_ +{ + /** + * The type of the operand. + */ + ZydisOperandType type; + /** + * Extended info for register-operands. + */ + struct ZydisEncoderOperandReg_ + { + /** + * The register value. + */ + ZydisRegister value; + /** + * Is this 4th operand (`VEX`/`XOP`). Despite its name, `is4` encoding can sometimes be + * applied to 3rd operand instead of 4th. This field is used to resolve such ambiguities. + * For all other operands it should be set to `ZYAN_FALSE`. + */ + ZyanBool is4; + } reg; + /** + * Extended info for memory-operands. + */ + struct ZydisEncoderOperandMem_ + { + /** + * The base register. + */ + ZydisRegister base; + /** + * The index register. + */ + ZydisRegister index; + /** + * The scale factor. + */ + ZyanU8 scale; + /** + * The displacement value. + */ + ZyanI64 displacement; + /** + * Size of this operand in bytes. + */ + ZyanU16 size; + } mem; + /** + * Extended info for pointer-operands. + */ + struct ZydisEncoderOperandPtr_ + { + /** + * The segment value. + */ + ZyanU16 segment; + /** + * The offset value. + */ + ZyanU32 offset; + } ptr; + /** + * Extended info for immediate-operands. + */ + union ZydisEncoderOperandImm_ + { + /** + * The unsigned immediate value. + */ + ZyanU64 u; + /** + * The signed immediate value. + */ + ZyanI64 s; + } imm; +} ZydisEncoderOperand; + +/** + * Main structure consumed by the encoder. It represents full semantics of an instruction. + */ +typedef struct ZydisEncoderRequest_ +{ + /** + * The machine mode used to encode this instruction. + */ + ZydisMachineMode machine_mode; + /** + * This optional field can be used to restrict allowed physical encodings for desired + * instruction. Some mnemonics can be supported by more than one encoding, so this field can + * resolve ambiguities e.g. you can disable `AVX-512` extensions by prohibiting usage of `EVEX` + * prefix and allow only `VEX` variants. + */ + ZydisEncodableEncoding allowed_encodings; + /** + * The instruction-mnemonic. + */ + ZydisMnemonic mnemonic; + /** + * A combination of requested encodable prefixes (`ZYDIS_ATTRIB_HAS_*` flags) for desired + * instruction. See `ZYDIS_ENCODABLE_PREFIXES` for list of available prefixes. + */ + ZydisInstructionAttributes prefixes; + /** + * Branch type (required for branching instructions only). Use `ZYDIS_BRANCH_TYPE_NONE` to let + * encoder pick size-optimal branch type automatically (`short` and `near` are prioritized over + * `far`). + */ + ZydisBranchType branch_type; + /** + * Specifies physical size for relative immediate operands. Use `ZYDIS_BRANCH_WIDTH_NONE` to + * let encoder pick size-optimal branch width automatically. For segment:offset `far` branches + * this field applies to physical size of the offset part. For branching instructions without + * relative operands this field affects effective operand size attribute. + */ + ZydisBranchWidth branch_width; + /** + * Optional address size hint used to resolve ambiguities for some instructions. Generally + * encoder deduces address size from `ZydisEncoderOperand` structures that represent + * explicit and implicit operands. This hint resolves conflicts when instruction's hidden + * operands scale with address size attribute. + */ + ZydisAddressSizeHint address_size_hint; + /** + * Optional operand size hint used to resolve ambiguities for some instructions. Generally + * encoder deduces operand size from `ZydisEncoderOperand` structures that represent + * explicit and implicit operands. This hint resolves conflicts when instruction's hidden + * operands scale with operand size attribute. + */ + ZydisOperandSizeHint operand_size_hint; + /** + * The number of instruction-operands. + */ + ZyanU8 operand_count; + /** + * Detailed info for all explicit and implicit instruction operands. + */ + ZydisEncoderOperand operands[ZYDIS_ENCODER_MAX_OPERANDS]; + /** + * Extended info for `EVEX` instructions. + */ + struct ZydisEncoderRequestEvexFeatures_ + { + /** + * The broadcast-mode. Specify `ZYDIS_BROADCAST_MODE_INVALID` for instructions with + * static broadcast functionality. + */ + ZydisBroadcastMode broadcast; + /** + * The rounding-mode. + */ + ZydisRoundingMode rounding; + /** + * Signals, if the `SAE` (suppress-all-exceptions) functionality should be enabled for + * the instruction. + */ + ZyanBool sae; + /** + * Signals, if the zeroing-mask functionality should be enabled for the instruction. + * Specify `ZYAN_TRUE` for instructions with forced zeroing mask. + */ + ZyanBool zeroing_mask; + } evex; + /** + * Extended info for `MVEX` instructions. + */ + struct ZydisEncoderRequestMvexFeatures_ + { + /** + * The broadcast-mode. + */ + ZydisBroadcastMode broadcast; + /** + * The data-conversion mode. + */ + ZydisConversionMode conversion; + /** + * The rounding-mode. + */ + ZydisRoundingMode rounding; + /** + * The `AVX` register-swizzle mode. + */ + ZydisSwizzleMode swizzle; + /** + * Signals, if the `SAE` (suppress-all-exceptions) functionality is enabled for + * the instruction. + */ + ZyanBool sae; + /** + * Signals, if the instruction has a memory-eviction-hint (`KNC` only). + */ + ZyanBool eviction_hint; + } mvex; +} ZydisEncoderRequest; + +/* ============================================================================================== */ +/* Exported functions */ +/* ============================================================================================== */ + +/** + * @addtogroup encoder Encoder + * Functions allowing encoding of instruction bytes from a machine interpretable struct. + * @{ + */ + +/** + * Encodes instruction with semantics specified in encoder request structure. + * + * @param request A pointer to the `ZydisEncoderRequest` struct. + * @param buffer A pointer to the output buffer receiving encoded instruction. + * @param length A pointer to the variable containing length of the output buffer. Upon + * successful return this variable receives length of the encoded instruction. + * + * @return A zyan status code. + */ +ZYDIS_EXPORT ZyanStatus ZydisEncoderEncodeInstruction(const ZydisEncoderRequest *request, + void *buffer, ZyanUSize *length); + +/** + * Encodes instruction with semantics specified in encoder request structure. This function expects + * absolute addresses inside encoder request instead of `EIP`/`RIP`-relative values. Function + * predicts final instruction length prior to encoding and writes back calculated relative operands + * to provided encoder request. + * + * @param request A pointer to the `ZydisEncoderRequest` struct. + * @param buffer A pointer to the output buffer receiving encoded instruction. + * @param length A pointer to the variable containing length of the output buffer. Upon + * successful return this variable receives length of the encoded + * instruction. + * @param runtime_address The runtime address of the instruction. + * + * @return A zyan status code. + */ +ZYDIS_EXPORT ZyanStatus ZydisEncoderEncodeInstructionAbsolute(ZydisEncoderRequest *request, + void *buffer, ZyanUSize *length, ZyanU64 runtime_address); + +/** + * Converts decoded instruction to encoder request that can be passed to + * `ZydisEncoderEncodeInstruction`. + * + * @param instruction A pointer to the `ZydisDecodedInstruction` struct. + * @param operands A pointer to the decoded operands. + * @param operand_count The operand count. + * @param request A pointer to the `ZydisEncoderRequest` struct, that receives + * information necessary for encoder to re-encode the instruction. + * + * This function performs simple structure conversion and does minimal sanity checks on the + * input. There's no guarantee that produced request will be accepted by + * `ZydisEncoderEncodeInstruction` if malformed `ZydisDecodedInstruction` or malformed + * `ZydisDecodedOperands` is passed to this function. + * + * @return A zyan status code. + */ +ZYDIS_EXPORT ZyanStatus ZydisEncoderDecodedInstructionToEncoderRequest( + const ZydisDecodedInstruction* instruction, const ZydisDecodedOperand* operands, + ZyanU8 operand_count, ZydisEncoderRequest* request); + +/** + * Fills provided buffer with `NOP` instructions using longest possible multi-byte instructions. + * + * @param buffer A pointer to the output buffer receiving encoded instructions. + * @param length Size of the output buffer. + * + * @return A zyan status code. + */ +ZYDIS_EXPORT ZyanStatus ZydisEncoderNopFill(void *buffer, ZyanUSize length); + +/** @} */ + +/* ============================================================================================== */ + +#ifdef __cplusplus +} +#endif + +#endif /* ZYDIS_ENCODER_H */ |