1455 lines · cpp
1//===-- interception_win.cpp ------------------------------------*- C++ -*-===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This file is a part of AddressSanitizer, an address sanity checker.10//11// Windows-specific interception methods.12//13// This file is implementing several hooking techniques to intercept calls14// to functions. The hooks are dynamically installed by modifying the assembly15// code.16//17// The hooking techniques are making assumptions on the way the code is18// generated and are safe under these assumptions.19//20// On 64-bit architecture, there is no direct 64-bit jump instruction. To allow21// arbitrary branching on the whole memory space, the notion of trampoline22// region is used. A trampoline region is a memory space withing 2G boundary23// where it is safe to add custom assembly code to build 64-bit jumps.24//25// Hooking techniques26// ==================27//28// 1) Detour29//30// The Detour hooking technique is assuming the presence of a header with31// padding and an overridable 2-bytes nop instruction (mov edi, edi). The32// nop instruction can safely be replaced by a 2-bytes jump without any need33// to save the instruction. A jump to the target is encoded in the function34// header and the nop instruction is replaced by a short jump to the header.35//36// head: 5 x nop head: jmp <hook>37// func: mov edi, edi --> func: jmp short <head>38// [...] real: [...]39//40// This technique is only implemented on 32-bit architecture.41// Most of the time, Windows API are hookable with the detour technique.42//43// 2) Redirect Jump44//45// The redirect jump is applicable when the first instruction is a direct46// jump. The instruction is replaced by jump to the hook.47//48// func: jmp <label> --> func: jmp <hook>49//50// On a 64-bit architecture, a trampoline is inserted.51//52// func: jmp <label> --> func: jmp <tramp>53// [...]54//55// [trampoline]56// tramp: jmp QWORD [addr]57// addr: .bytes <hook>58//59// Note: <real> is equivalent to <label>.60//61// 3) HotPatch62//63// The HotPatch hooking is assuming the presence of a header with padding64// and a first instruction with at least 2-bytes.65//66// The reason to enforce the 2-bytes limitation is to provide the minimal67// space to encode a short jump. HotPatch technique is only rewriting one68// instruction to avoid breaking a sequence of instructions containing a69// branching target.70//71// Assumptions are enforced by MSVC compiler by using the /HOTPATCH flag.72// see: https://msdn.microsoft.com/en-us/library/ms173507.aspx73// Default padding length is 5 bytes in 32-bits and 6 bytes in 64-bits.74//75// head: 5 x nop head: jmp <hook>76// func: <instr> --> func: jmp short <head>77// [...] body: [...]78//79// [trampoline]80// real: <instr>81// jmp <body>82//83// On a 64-bit architecture:84//85// head: 6 x nop head: jmp QWORD [addr1]86// func: <instr> --> func: jmp short <head>87// [...] body: [...]88//89// [trampoline]90// addr1: .bytes <hook>91// real: <instr>92// jmp QWORD [addr2]93// addr2: .bytes <body>94//95// 4) Trampoline96//97// The Trampoline hooking technique is the most aggressive one. It is98// assuming that there is a sequence of instructions that can be safely99// replaced by a jump (enough room and no incoming branches).100//101// Unfortunately, these assumptions can't be safely presumed and code may102// be broken after hooking.103//104// func: <instr> --> func: jmp <hook>105// <instr>106// [...] body: [...]107//108// [trampoline]109// real: <instr>110// <instr>111// jmp <body>112//113// On a 64-bit architecture:114//115// func: <instr> --> func: jmp QWORD [addr1]116// <instr>117// [...] body: [...]118//119// [trampoline]120// addr1: .bytes <hook>121// real: <instr>122// <instr>123// jmp QWORD [addr2]124// addr2: .bytes <body>125//===----------------------------------------------------------------------===//126 127#include "interception.h"128 129#if SANITIZER_WINDOWS130#include "sanitizer_common/sanitizer_platform.h"131#define WIN32_LEAN_AND_MEAN132#include <windows.h>133#include <psapi.h>134 135namespace __interception {136 137static const int kAddressLength = FIRST_32_SECOND_64(4, 8);138static const int kJumpInstructionLength = 5;139static const int kShortJumpInstructionLength = 2;140UNUSED static const int kIndirectJumpInstructionLength = 6;141static const int kBranchLength =142 FIRST_32_SECOND_64(kJumpInstructionLength, kIndirectJumpInstructionLength);143static const int kDirectBranchLength = kBranchLength + kAddressLength;144 145# if defined(_MSC_VER)146# define INTERCEPTION_FORMAT(f, a)147# else148# define INTERCEPTION_FORMAT(f, a) __attribute__((format(printf, f, a)))149# endif150 151static void (*ErrorReportCallback)(const char *format, ...)152 INTERCEPTION_FORMAT(1, 2);153 154void SetErrorReportCallback(void (*callback)(const char *format, ...)) {155 ErrorReportCallback = callback;156}157 158# define ReportError(...) \159 do { \160 if (ErrorReportCallback) \161 ErrorReportCallback(__VA_ARGS__); \162 } while (0)163 164static void InterceptionFailed() {165 ReportError("interception_win: failed due to an unrecoverable error.\n");166 // This acts like an abort when no debugger is attached. According to an old167 // comment, calling abort() leads to an infinite recursion in CheckFailed.168 __debugbreak();169}170 171static bool DistanceIsWithin2Gig(uptr from, uptr target) {172#if SANITIZER_WINDOWS64173 if (from < target)174 return target - from <= (uptr)0x7FFFFFFFU;175 else176 return from - target <= (uptr)0x80000000U;177#else178 // In a 32-bit address space, the address calculation will wrap, so this check179 // is unnecessary.180 return true;181#endif182}183 184static uptr GetMmapGranularity() {185 SYSTEM_INFO si;186 GetSystemInfo(&si);187 return si.dwAllocationGranularity;188}189 190UNUSED static uptr RoundDownTo(uptr size, uptr boundary) {191 return size & ~(boundary - 1);192}193 194UNUSED static uptr RoundUpTo(uptr size, uptr boundary) {195 return RoundDownTo(size + boundary - 1, boundary);196}197 198// FIXME: internal_str* and internal_mem* functions should be moved from the199// ASan sources into interception/.200 201static size_t _strlen(const char *str) {202 const char* p = str;203 while (*p != '\0') ++p;204 return p - str;205}206 207static char* _strchr(char* str, char c) {208 while (*str) {209 if (*str == c)210 return str;211 ++str;212 }213 return nullptr;214}215 216static int _strcmp(const char *s1, const char *s2) {217 while (true) {218 unsigned c1 = *s1;219 unsigned c2 = *s2;220 if (c1 != c2) return (c1 < c2) ? -1 : 1;221 if (c1 == 0) break;222 s1++;223 s2++;224 }225 return 0;226}227 228static void _memset(void *p, int value, size_t sz) {229 for (size_t i = 0; i < sz; ++i)230 ((char*)p)[i] = (char)value;231}232 233static void _memcpy(void *dst, void *src, size_t sz) {234 char *dst_c = (char*)dst,235 *src_c = (char*)src;236 for (size_t i = 0; i < sz; ++i)237 dst_c[i] = src_c[i];238}239 240static bool ChangeMemoryProtection(241 uptr address, uptr size, DWORD *old_protection) {242 return ::VirtualProtect((void*)address, size,243 PAGE_EXECUTE_READWRITE,244 old_protection) != FALSE;245}246 247static bool RestoreMemoryProtection(248 uptr address, uptr size, DWORD old_protection) {249 DWORD unused;250 return ::VirtualProtect((void*)address, size,251 old_protection,252 &unused) != FALSE;253}254 255static bool IsMemoryPadding(uptr address, uptr size) {256 u8* function = (u8*)address;257 for (size_t i = 0; i < size; ++i)258 if (function[i] != 0x90 && function[i] != 0xCC)259 return false;260 return true;261}262 263static const u8 kHintNop8Bytes[] = {264 0x0F, 0x1F, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00265};266 267template<class T>268static bool FunctionHasPrefix(uptr address, const T &pattern) {269 u8* function = (u8*)address - sizeof(pattern);270 for (size_t i = 0; i < sizeof(pattern); ++i)271 if (function[i] != pattern[i])272 return false;273 return true;274}275 276static bool FunctionHasPadding(uptr address, uptr size) {277 if (IsMemoryPadding(address - size, size))278 return true;279 if (size <= sizeof(kHintNop8Bytes) &&280 FunctionHasPrefix(address, kHintNop8Bytes))281 return true;282 return false;283}284 285static void WritePadding(uptr from, uptr size) {286 _memset((void*)from, 0xCC, (size_t)size);287}288 289static void WriteJumpInstruction(uptr from, uptr target) {290 if (!DistanceIsWithin2Gig(from + kJumpInstructionLength, target)) {291 ReportError(292 "interception_win: cannot write jmp further than 2GB away, from %p to "293 "%p.\n",294 (void *)from, (void *)target);295 InterceptionFailed();296 }297 ptrdiff_t offset = target - from - kJumpInstructionLength;298 *(u8*)from = 0xE9;299 *(u32*)(from + 1) = offset;300}301 302static void WriteShortJumpInstruction(uptr from, uptr target) {303 sptr offset = target - from - kShortJumpInstructionLength;304 if (offset < -128 || offset > 127) {305 ReportError("interception_win: cannot write short jmp from %p to %p\n",306 (void *)from, (void *)target);307 InterceptionFailed();308 }309 *(u8*)from = 0xEB;310 *(u8*)(from + 1) = (u8)offset;311}312 313#if SANITIZER_WINDOWS64314static void WriteIndirectJumpInstruction(uptr from, uptr indirect_target) {315 // jmp [rip + <offset>] = FF 25 <offset> where <offset> is a relative316 // offset.317 // The offset is the distance from then end of the jump instruction to the318 // memory location containing the targeted address. The displacement is still319 // 32-bit in x64, so indirect_target must be located within +/- 2GB range.320 int offset = indirect_target - from - kIndirectJumpInstructionLength;321 if (!DistanceIsWithin2Gig(from + kIndirectJumpInstructionLength,322 indirect_target)) {323 ReportError(324 "interception_win: cannot write indirect jmp with target further than "325 "2GB away, from %p to %p.\n",326 (void *)from, (void *)indirect_target);327 InterceptionFailed();328 }329 *(u16*)from = 0x25FF;330 *(u32*)(from + 2) = offset;331}332#endif333 334static void WriteBranch(335 uptr from, uptr indirect_target, uptr target) {336#if SANITIZER_WINDOWS64337 WriteIndirectJumpInstruction(from, indirect_target);338 *(u64*)indirect_target = target;339#else340 (void)indirect_target;341 WriteJumpInstruction(from, target);342#endif343}344 345static void WriteDirectBranch(uptr from, uptr target) {346#if SANITIZER_WINDOWS64347 // Emit an indirect jump through immediately following bytes:348 // jmp [rip + kBranchLength]349 // .quad <target>350 WriteBranch(from, from + kBranchLength, target);351#else352 WriteJumpInstruction(from, target);353#endif354}355 356struct TrampolineMemoryRegion {357 uptr content;358 uptr allocated_size;359 uptr max_size;360};361 362UNUSED static const uptr kTrampolineRangeLimit = 1ull << 31; // 2 gig363static const int kMaxTrampolineRegion = 1024;364static TrampolineMemoryRegion TrampolineRegions[kMaxTrampolineRegion];365 366static void *AllocateTrampolineRegion(uptr min_addr, uptr max_addr,367 uptr func_addr, size_t granularity) {368# if SANITIZER_WINDOWS64369 // Clamp {min,max}_addr to the accessible address space.370 SYSTEM_INFO system_info;371 ::GetSystemInfo(&system_info);372 uptr min_virtual_addr =373 RoundUpTo((uptr)system_info.lpMinimumApplicationAddress, granularity);374 uptr max_virtual_addr =375 RoundDownTo((uptr)system_info.lpMaximumApplicationAddress, granularity);376 if (min_addr < min_virtual_addr)377 min_addr = min_virtual_addr;378 if (max_addr > max_virtual_addr)379 max_addr = max_virtual_addr;380 381 // This loop probes the virtual address space to find free memory in the382 // [min_addr, max_addr] interval. The search starts from func_addr and383 // proceeds "outwards" towards the interval bounds using two probes, lo_addr384 // and hi_addr, for addresses lower/higher than func_addr. At each step, it385 // considers the probe closest to func_addr. If that address is not free, the386 // probe is advanced (lower or higher depending on the probe) to the next387 // memory block and the search continues.388 uptr lo_addr = RoundDownTo(func_addr, granularity);389 uptr hi_addr = RoundUpTo(func_addr, granularity);390 while (lo_addr >= min_addr || hi_addr <= max_addr) {391 // Consider the in-range address closest to func_addr.392 uptr addr;393 if (lo_addr < min_addr)394 addr = hi_addr;395 else if (hi_addr > max_addr)396 addr = lo_addr;397 else398 addr = (hi_addr - func_addr < func_addr - lo_addr) ? hi_addr : lo_addr;399 400 MEMORY_BASIC_INFORMATION info;401 if (!::VirtualQuery((void *)addr, &info, sizeof(info))) {402 ReportError(403 "interception_win: VirtualQuery in AllocateTrampolineRegion failed "404 "for %p\n",405 (void *)addr);406 return nullptr;407 }408 409 // Check whether a region can be allocated at |addr|.410 if (info.State == MEM_FREE && info.RegionSize >= granularity) {411 void *page =412 ::VirtualAlloc((void *)addr, granularity, MEM_RESERVE | MEM_COMMIT,413 PAGE_EXECUTE_READWRITE);414 if (page == nullptr)415 ReportError(416 "interception_win: VirtualAlloc in AllocateTrampolineRegion failed "417 "for %p\n",418 (void *)addr);419 return page;420 }421 422 if (addr == lo_addr)423 lo_addr =424 RoundDownTo((uptr)info.AllocationBase - granularity, granularity);425 if (addr == hi_addr)426 hi_addr =427 RoundUpTo((uptr)info.BaseAddress + info.RegionSize, granularity);428 }429 430 ReportError(431 "interception_win: AllocateTrampolineRegion failed to find free memory; "432 "min_addr: %p, max_addr: %p, func_addr: %p, granularity: %zu\n",433 (void *)min_addr, (void *)max_addr, (void *)func_addr, granularity);434 return nullptr;435#else436 return ::VirtualAlloc(nullptr,437 granularity,438 MEM_RESERVE | MEM_COMMIT,439 PAGE_EXECUTE_READWRITE);440#endif441}442 443// Used by unittests to release mapped memory space.444void TestOnlyReleaseTrampolineRegions() {445 for (size_t bucket = 0; bucket < kMaxTrampolineRegion; ++bucket) {446 TrampolineMemoryRegion *current = &TrampolineRegions[bucket];447 if (current->content == 0)448 return;449 ::VirtualFree((void*)current->content, 0, MEM_RELEASE);450 current->content = 0;451 }452}453 454static uptr AllocateMemoryForTrampoline(uptr func_address, size_t size) {455# if SANITIZER_WINDOWS64456 uptr min_addr = func_address - kTrampolineRangeLimit;457 uptr max_addr = func_address + kTrampolineRangeLimit - size;458 459 // Allocate memory within 2GB of the module (DLL or EXE file) so that any460 // address within the module can be referenced with PC-relative operands.461 // This allows us to not just jump to the trampoline with a PC-relative462 // offset, but to relocate any instructions that we copy to the trampoline463 // which have references to the original module. If we can't find the base464 // address of the module (e.g. if func_address is in mmap'ed memory), just465 // stay within 2GB of func_address.466 HMODULE module;467 if (::GetModuleHandleExW(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS |468 GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT,469 (LPCWSTR)func_address, &module)) {470 MODULEINFO module_info;471 if (::GetModuleInformation(::GetCurrentProcess(), module,472 &module_info, sizeof(module_info))) {473 min_addr = (uptr)module_info.lpBaseOfDll + module_info.SizeOfImage -474 kTrampolineRangeLimit;475 max_addr = (uptr)module_info.lpBaseOfDll + kTrampolineRangeLimit - size;476 }477 }478 479 // Check for overflow.480 if (min_addr > func_address)481 min_addr = 0;482 if (max_addr < func_address)483 max_addr = ~(uptr)0;484# else485 uptr min_addr = 0;486 uptr max_addr = ~min_addr;487# endif488 489 // Find a region within [min_addr,max_addr] with enough space to allocate490 // |size| bytes.491 TrampolineMemoryRegion *region = nullptr;492 for (size_t bucket = 0; bucket < kMaxTrampolineRegion; ++bucket) {493 TrampolineMemoryRegion* current = &TrampolineRegions[bucket];494 if (current->content == 0) {495 // No valid region found, allocate a new region.496 size_t bucket_size = GetMmapGranularity();497 void *content = AllocateTrampolineRegion(min_addr, max_addr, func_address,498 bucket_size);499 if (content == nullptr)500 return 0U;501 502 current->content = (uptr)content;503 current->allocated_size = 0;504 current->max_size = bucket_size;505 region = current;506 break;507 } else if (current->max_size - current->allocated_size > size) {508 uptr next_address = current->content + current->allocated_size;509 if (next_address < min_addr || next_address > max_addr)510 continue;511 // The space can be allocated in the current region.512 region = current;513 break;514 }515 }516 517 // Failed to find a region.518 if (region == nullptr)519 return 0U;520 521 // Allocate the space in the current region.522 uptr allocated_space = region->content + region->allocated_size;523 region->allocated_size += size;524 WritePadding(allocated_space, size);525 526 return allocated_space;527}528 529// The following prologues cannot be patched because of the short jump530// jumping to the patching region.531 532// Short jump patterns below are only for x86_64.533# if SANITIZER_WINDOWS_x64534// ntdll!wcslen in Win11535// 488bc1 mov rax,rcx536// 0fb710 movzx edx,word ptr [rax]537// 4883c002 add rax,2538// 6685d2 test dx,dx539// 75f4 jne -12540static const u8 kPrologueWithShortJump1[] = {541 0x48, 0x8b, 0xc1, 0x0f, 0xb7, 0x10, 0x48, 0x83,542 0xc0, 0x02, 0x66, 0x85, 0xd2, 0x75, 0xf4,543};544 545// ntdll!strrchr in Win11546// 4c8bc1 mov r8,rcx547// 8a01 mov al,byte ptr [rcx]548// 48ffc1 inc rcx549// 84c0 test al,al550// 75f7 jne -9551static const u8 kPrologueWithShortJump2[] = {552 0x4c, 0x8b, 0xc1, 0x8a, 0x01, 0x48, 0xff, 0xc1,553 0x84, 0xc0, 0x75, 0xf7,554};555#endif556 557// Returns 0 on error.558static size_t GetInstructionSize(uptr address, size_t* rel_offset = nullptr) {559 if (rel_offset) {560 *rel_offset = 0;561 }562 563#if SANITIZER_ARM64564 // An ARM64 instruction is 4 bytes long.565 return 4;566#endif567 568# if SANITIZER_WINDOWS_x64569 if (memcmp((u8*)address, kPrologueWithShortJump1,570 sizeof(kPrologueWithShortJump1)) == 0 ||571 memcmp((u8*)address, kPrologueWithShortJump2,572 sizeof(kPrologueWithShortJump2)) == 0) {573 return 0;574 }575#endif576 577 switch (*(u64*)address) {578 case 0x90909090909006EB: // stub: jmp over 6 x nop.579 return 8;580 }581 582 switch (*(u8*)address) {583 case 0x90: // 90 : nop584 case 0xC3: // C3 : ret (for small/empty function interception585 case 0xCC: // CC : int 3 i.e. registering weak functions)586 return 1;587 588 case 0x50: // push eax / rax589 case 0x51: // push ecx / rcx590 case 0x52: // push edx / rdx591 case 0x53: // push ebx / rbx592 case 0x54: // push esp / rsp593 case 0x55: // push ebp / rbp594 case 0x56: // push esi / rsi595 case 0x57: // push edi / rdi596 case 0x5D: // pop ebp / rbp597 return 1;598 599 case 0x6A: // 6A XX = push XX600 return 2;601 602 // This instruction can be encoded with a 16-bit immediate but that is603 // incredibly unlikely.604 case 0x68: // 68 XX XX XX XX : push imm32605 return 5;606 607 case 0xb8: // b8 XX XX XX XX : mov eax, XX XX XX XX608 case 0xB9: // b9 XX XX XX XX : mov ecx, XX XX XX XX609 case 0xBA: // ba XX XX XX XX : mov edx, XX XX XX XX610 return 5;611 612 // Cannot overwrite control-instruction. Return 0 to indicate failure.613 case 0xE9: // E9 XX XX XX XX : jmp <label>614 case 0xE8: // E8 XX XX XX XX : call <func>615 case 0xEB: // EB XX : jmp XX (short jump)616 case 0x70: // 7Y YY : jy XX (short conditional jump)617 case 0x71:618 case 0x72:619 case 0x73:620 case 0x74:621 case 0x75:622 case 0x76:623 case 0x77:624 case 0x78:625 case 0x79:626 case 0x7A:627 case 0x7B:628 case 0x7C:629 case 0x7D:630 case 0x7E:631 case 0x7F:632 return 0;633 }634 635 switch (*(u16*)(address)) {636 case 0x018A: // 8A 01 : mov al, byte ptr [ecx]637 case 0xFF8B: // 8B FF : mov edi, edi638 case 0xEC8B: // 8B EC : mov ebp, esp639 case 0xc889: // 89 C8 : mov eax, ecx640 case 0xD189: // 89 D1 : mov ecx, edx641 case 0xE589: // 89 E5 : mov ebp, esp642 case 0xC18B: // 8B C1 : mov eax, ecx643 case 0xC031: // 31 C0 : xor eax, eax644 case 0xC931: // 31 C9 : xor ecx, ecx645 case 0xD231: // 31 D2 : xor edx, edx646 case 0xC033: // 33 C0 : xor eax, eax647 case 0xC933: // 33 C9 : xor ecx, ecx648 case 0xD233: // 33 D2 : xor edx, edx649 case 0xFF33: // 33 FF : xor edi, edi650 case 0x9066: // 66 90 : xchg %ax,%ax (Two-byte NOP)651 case 0xDB84: // 84 DB : test bl,bl652 case 0xC084: // 84 C0 : test al,al653 case 0xC984: // 84 C9 : test cl,cl654 case 0xD284: // 84 D2 : test dl,dl655 return 2;656 657 case 0x3980: // 80 39 XX : cmp BYTE PTR [rcx], XX658 case 0x4D8B: // 8B 4D XX : mov XX(%ebp), ecx659 case 0x558B: // 8B 55 XX : mov XX(%ebp), edx660 case 0x758B: // 8B 75 XX : mov XX(%ebp), esp661 case 0xE483: // 83 E4 XX : and esp, XX662 case 0xEC83: // 83 EC XX : sub esp, XX663 case 0xC1F6: // F6 C1 XX : test cl, XX664 return 3;665 666 case 0x89FF: // FF 89 XX XX XX XX : dec dword ptr [ecx + XX XX XX XX]667 case 0xEC81: // 81 EC XX XX XX XX : sub esp, XX XX XX XX668 return 6;669 670 // Cannot overwrite control-instruction. Return 0 to indicate failure.671 case 0x25FF: // FF 25 XX YY ZZ WW : jmp dword ptr ds:[WWZZYYXX]672 return 0;673 }674 675 switch (0x00FFFFFF & *(u32 *)address) {676 case 0x244C8D: // 8D 4C 24 XX : lea ecx, [esp + XX]677 case 0x2474FF: // FF 74 24 XX : push qword ptr [rsp + XX]678 return 4;679 case 0x24A48D: // 8D A4 24 XX XX XX XX : lea esp, [esp + XX XX XX XX]680 return 7;681 }682 683 switch (0x000000FF & *(u32 *)address) {684 case 0xc2: // C2 XX XX : ret XX (needed for registering weak functions)685 return 3;686 }687 688# if SANITIZER_WINDOWS_x64689 switch (*(u8*)address) {690 case 0xA1: // A1 XX XX XX XX XX XX XX XX :691 // movabs eax, dword ptr ds:[XXXXXXXX]692 return 9;693 case 0xF2:694 switch (*(u32 *)(address + 1)) {695 case 0x2444110f: // f2 0f 11 44 24 XX movsd QWORD PTR696 // [rsp + XX], xmm0697 case 0x244c110f: // f2 0f 11 4c 24 XX movsd QWORD PTR698 // [rsp + XX], xmm1699 case 0x2454110f: // f2 0f 11 54 24 XX movsd QWORD PTR700 // [rsp + XX], xmm2701 case 0x245c110f: // f2 0f 11 5c 24 XX movsd QWORD PTR702 // [rsp + XX], xmm3703 case 0x2464110f: // f2 0f 11 64 24 XX movsd QWORD PTR704 // [rsp + XX], xmm4705 return 6;706 }707 break;708 709 case 0x83:710 const u8 next_byte = *(u8*)(address + 1);711 const u8 mod = next_byte >> 6;712 const u8 rm = next_byte & 7;713 if (mod == 1 && rm == 4)714 return 5; // 83 ModR/M SIB Disp8 Imm8715 // add|or|adc|sbb|and|sub|xor|cmp [r+disp8], imm8716 }717 718 switch (*(u16*)address) {719 case 0x5040: // push rax720 case 0x5140: // push rcx721 case 0x5240: // push rdx722 case 0x5340: // push rbx723 case 0x5440: // push rsp724 case 0x5540: // push rbp725 case 0x5640: // push rsi726 case 0x5740: // push rdi727 case 0x5441: // push r12728 case 0x5541: // push r13729 case 0x5641: // push r14730 case 0x5741: // push r15731 case 0xc084: // test al, al732 case 0x018a: // mov al, byte ptr [rcx]733 return 2;734 735 case 0x7E80: // 80 7E YY XX cmp BYTE PTR [rsi+YY], XX736 case 0x7D80: // 80 7D YY XX cmp BYTE PTR [rbp+YY], XX737 case 0x7A80: // 80 7A YY XX cmp BYTE PTR [rdx+YY], XX738 case 0x7880: // 80 78 YY XX cmp BYTE PTR [rax+YY], XX739 case 0x7B80: // 80 7B YY XX cmp BYTE PTR [rbx+YY], XX740 case 0x7980: // 80 79 YY XX cmp BYTE ptr [rcx+YY], XX741 return 4;742 743 case 0x058A: // 8A 05 XX XX XX XX : mov al, byte ptr [XX XX XX XX]744 case 0x058B: // 8B 05 XX XX XX XX : mov eax, dword ptr [XX XX XX XX]745 if (rel_offset)746 *rel_offset = 2;747 FALLTHROUGH;748 case 0xB841: // 41 B8 XX XX XX XX : mov r8d, XX XX XX XX749 return 6;750 751 case 0x7E81: // 81 7E YY XX XX XX XX cmp DWORD PTR [rsi+YY], XX XX XX XX752 case 0x7D81: // 81 7D YY XX XX XX XX cmp DWORD PTR [rbp+YY], XX XX XX XX753 case 0x7A81: // 81 7A YY XX XX XX XX cmp DWORD PTR [rdx+YY], XX XX XX XX754 case 0x7881: // 81 78 YY XX XX XX XX cmp DWORD PTR [rax+YY], XX XX XX XX755 case 0x7B81: // 81 7B YY XX XX XX XX cmp DWORD PTR [rbx+YY], XX XX XX XX756 case 0x7981: // 81 79 YY XX XX XX XX cmp dword ptr [rcx+YY], XX XX XX XX757 return 7;758 759 case 0xb848: // 48 b8 XX XX XX XX XX XX XX XX :760 // movabsq XX XX XX XX XX XX XX XX, rax761 case 0xba48: // 48 ba XX XX XX XX XX XX XX XX :762 // movabsq XX XX XX XX XX XX XX XX, rdx763 return 10;764 }765 766 switch (0x00FFFFFF & *(u32 *)address) {767 case 0x10b70f: // 0f b7 10 : movzx edx, WORD PTR [rax]768 case 0x02b70f: // 0f b7 02 : movzx eax, WORD PTR [rdx]769 case 0xc00b4d: // 4d 0b c0 : or r8, r8770 case 0xc03345: // 45 33 c0 : xor r8d, r8d771 case 0xc08548: // 48 85 c0 : test rax, rax772 case 0xc0854d: // 4d 85 c0 : test r8, r8773 case 0xc08b41: // 41 8b c0 : mov eax, r8d774 case 0xc0ff48: // 48 ff c0 : inc rax775 case 0xc0ff49: // 49 ff c0 : inc r8776 case 0xc18b41: // 41 8b c1 : mov eax, r9d777 case 0xc18b48: // 48 8b c1 : mov rax, rcx778 case 0xc18b4c: // 4c 8b c1 : mov r8, rcx779 case 0xc1ff48: // 48 ff c1 : inc rcx780 case 0xc1ff49: // 49 ff c1 : inc r9781 case 0xc28b41: // 41 8b c2 : mov eax, r10d782 case 0x01b60f: // 0f b6 01 : movzx eax, BYTE PTR [rcx]783 case 0x09b60f: // 0f b6 09 : movzx ecx, BYTE PTR [rcx]784 case 0x11b60f: // 0f b6 11 : movzx edx, BYTE PTR [rcx]785 case 0xc2b60f: // 0f b6 c2 : movzx eax, dl786 case 0xc2ff48: // 48 ff c2 : inc rdx787 case 0xc2ff49: // 49 ff c2 : inc r10788 case 0xc38b41: // 41 8b c3 : mov eax, r11d789 case 0xc3ff48: // 48 ff c3 : inc rbx790 case 0xc3ff49: // 49 ff c3 : inc r11791 case 0xc48b41: // 41 8b c4 : mov eax, r12d792 case 0xc48b48: // 48 8b c4 : mov rax, rsp793 case 0xc4ff49: // 49 ff c4 : inc r12794 case 0xc5ff49: // 49 ff c5 : inc r13795 case 0xc6ff48: // 48 ff c6 : inc rsi796 case 0xc6ff49: // 49 ff c6 : inc r14797 case 0xc7ff48: // 48 ff c7 : inc rdi798 case 0xc7ff49: // 49 ff c7 : inc r15799 case 0xc93345: // 45 33 c9 : xor r9d, r9d800 case 0xc98548: // 48 85 c9 : test rcx, rcx801 case 0xc9854d: // 4d 85 c9 : test r9, r9802 case 0xc98b4c: // 4c 8b c9 : mov r9, rcx803 case 0xd12948: // 48 29 d1 : sub rcx, rdx804 case 0xc22b4c: // 4c 2b c2 : sub r8, rdx805 case 0xca2b48: // 48 2b ca : sub rcx, rdx806 case 0xca3b48: // 48 3b ca : cmp rcx, rdx807 case 0xd12b48: // 48 2b d1 : sub rdx, rcx808 case 0xd18b48: // 48 8b d1 : mov rdx, rcx809 case 0xd18b4c: // 4c 8b d1 : mov r10, rcx810 case 0xd28548: // 48 85 d2 : test rdx, rdx811 case 0xd2854d: // 4d 85 d2 : test r10, r10812 case 0xd28b4c: // 4c 8b d2 : mov r10, rdx813 case 0xd2b60f: // 0f b6 d2 : movzx edx, dl814 case 0xd2be0f: // 0f be d2 : movsx edx, dl815 case 0xd98b4c: // 4c 8b d9 : mov r11, rcx816 case 0xd9f748: // 48 f7 d9 : neg rcx817 case 0xc03145: // 45 31 c0 : xor r8d,r8d818 case 0xc93145: // 45 31 c9 : xor r9d,r9d819 case 0xd23345: // 45 33 d2 : xor r10d, r10d820 case 0xdb3345: // 45 33 db : xor r11d, r11d821 case 0xc08445: // 45 84 c0 : test r8b,r8b822 case 0xd28445: // 45 84 d2 : test r10b,r10b823 case 0xdb8548: // 48 85 db : test rbx, rbx824 case 0xdb854d: // 4d 85 db : test r11, r11825 case 0xdc8b4c: // 4c 8b dc : mov r11, rsp826 case 0xe48548: // 48 85 e4 : test rsp, rsp827 case 0xe4854d: // 4d 85 e4 : test r12, r12828 case 0xc88948: // 48 89 c8 : mov rax,rcx829 case 0xcb8948: // 48 89 cb : mov rbx,rcx830 case 0xd08948: // 48 89 d0 : mov rax,rdx831 case 0xd18948: // 48 89 d1 : mov rcx,rdx832 case 0xd38948: // 48 89 d3 : mov rbx,rdx833 case 0xe58948: // 48 89 e5 : mov rbp, rsp834 case 0xed8548: // 48 85 ed : test rbp, rbp835 case 0xc88949: // 49 89 c8 : mov r8, rcx836 case 0xc98949: // 49 89 c9 : mov r9, rcx837 case 0xca8949: // 49 89 ca : mov r10,rcx838 case 0xd08949: // 49 89 d0 : mov r8, rdx839 case 0xd18949: // 49 89 d1 : mov r9, rdx840 case 0xd28949: // 49 89 d2 : mov r10, rdx841 case 0xd38949: // 49 89 d3 : mov r11, rdx842 case 0xed854d: // 4d 85 ed : test r13, r13843 case 0xf6854d: // 4d 85 f6 : test r14, r14844 case 0xff854d: // 4d 85 ff : test r15, r15845 return 3;846 847 case 0x245489: // 89 54 24 XX : mov DWORD PTR[rsp + XX], edx848 case 0x428d44: // 44 8d 42 XX : lea r8d , [rdx + XX]849 case 0x588948: // 48 89 58 XX : mov QWORD PTR[rax + XX], rbx850 case 0xec8348: // 48 83 ec XX : sub rsp, XX851 case 0xf88349: // 49 83 f8 XX : cmp r8, XX852 case 0x488d49: // 49 8d 48 XX : lea rcx, [...]853 case 0x048d4c: // 4c 8d 04 XX : lea r8, [...]854 case 0x148d4e: // 4e 8d 14 XX : lea r10, [...]855 case 0x398366: // 66 83 39 XX : cmp WORD PTR [rcx], XX856 return 4;857 858 case 0x441F0F: // 0F 1F 44 XX XX : nop DWORD PTR [...]859 case 0x246483: // 83 64 24 XX YY : and DWORD PTR [rsp+XX], YY860 return 5;861 862 case 0x788166: // 66 81 78 XX YY YY cmp WORD PTR [rax+XX], YY YY863 case 0x798166: // 66 81 79 XX YY YY cmp WORD PTR [rcx+XX], YY YY864 case 0x7a8166: // 66 81 7a XX YY YY cmp WORD PTR [rdx+XX], YY YY865 case 0x7b8166: // 66 81 7b XX YY YY cmp WORD PTR [rbx+XX], YY YY866 case 0x7e8166: // 66 81 7e XX YY YY cmp WORD PTR [rsi+XX], YY YY867 case 0x7f8166: // 66 81 7f XX YY YY cmp WORD PTR [rdi+XX], YY YY868 return 6;869 870 case 0xec8148: // 48 81 EC XX XX XX XX : sub rsp, XXXXXXXX871 case 0xc0c748: // 48 C7 C0 XX XX XX XX : mov rax, XX XX XX XX872 return 7;873 874 // clang-format off875 case 0x788141: // 41 81 78 XX YY YY YY YY : cmp DWORD PTR [r8+YY], XX XX XX XX876 case 0x798141: // 41 81 79 XX YY YY YY YY : cmp DWORD PTR [r9+YY], XX XX XX XX877 case 0x7a8141: // 41 81 7a XX YY YY YY YY : cmp DWORD PTR [r10+YY], XX XX XX XX878 case 0x7b8141: // 41 81 7b XX YY YY YY YY : cmp DWORD PTR [r11+YY], XX XX XX XX879 case 0x7d8141: // 41 81 7d XX YY YY YY YY : cmp DWORD PTR [r13+YY], XX XX XX XX880 case 0x7e8141: // 41 81 7e XX YY YY YY YY : cmp DWORD PTR [r14+YY], XX XX XX XX881 case 0x7f8141: // 41 81 7f YY XX XX XX XX : cmp DWORD PTR [r15+YY], XX XX XX XX882 case 0x247c81: // 81 7c 24 YY XX XX XX XX : cmp DWORD PTR [rsp+YY], XX XX XX XX883 return 8;884 // clang-format on885 886 case 0x058b48: // 48 8b 05 XX XX XX XX :887 // mov rax, QWORD PTR [rip + XXXXXXXX]888 case 0x058d48: // 48 8d 05 XX XX XX XX :889 // lea rax, QWORD PTR [rip + XXXXXXXX]890 case 0x0d8948: // 48 89 0d XX XX XX XX :891 // mov QWORD PTR [rip + XXXXXXXX], rcx892 case 0x158948: // 48 89 15 XX XX XX XX :893 // mov QWORD PTR [rip + XXXXXXXX], rdx894 case 0x25ff48: // 48 ff 25 XX XX XX XX :895 // rex.W jmp QWORD PTR [rip + XXXXXXXX]896 case 0x158D4C: // 4c 8d 15 XX XX XX XX : lea r10, [rip + XX]897 // Instructions having offset relative to 'rip' need offset adjustment.898 if (rel_offset)899 *rel_offset = 3;900 return 7;901 902 case 0x2444c7: // C7 44 24 XX YY YY YY YY903 // mov dword ptr [rsp + XX], YYYYYYYY904 return 8;905 906 case 0x7c8141: // 41 81 7c ZZ YY XX XX XX XX907 // cmp DWORD PTR [reg+reg*n+YY], XX XX XX XX908 return 9;909 }910 911 switch (*(u32*)(address)) {912 case 0x01b60f44: // 44 0f b6 01 : movzx r8d, BYTE PTR [rcx]913 case 0x09b60f44: // 44 0f b6 09 : movzx r9d, BYTE PTR [rcx]914 case 0x0ab60f44: // 44 0f b6 0a : movzx r8d, BYTE PTR [rdx]915 case 0x11b60f44: // 44 0f b6 11 : movzx r10d, BYTE PTR [rcx]916 case 0x1ab60f44: // 44 0f b6 1a : movzx r11d, BYTE PTR [rdx]917 return 4;918 case 0x24448b48: // 48 8b 44 24 XX : mov rax, QWORD ptr [rsp + XX]919 case 0x246c8948: // 48 89 6C 24 XX : mov QWORD ptr [rsp + XX], rbp920 case 0x245c8948: // 48 89 5c 24 XX : mov QWORD PTR [rsp + XX], rbx921 case 0x24748948: // 48 89 74 24 XX : mov QWORD PTR [rsp + XX], rsi922 case 0x247c8948: // 48 89 7c 24 XX : mov QWORD PTR [rsp + XX], rdi923 case 0x244C8948: // 48 89 4C 24 XX : mov QWORD PTR [rsp + XX], rcx924 case 0x24548948: // 48 89 54 24 XX : mov QWORD PTR [rsp + XX], rdx925 case 0x244c894c: // 4c 89 4c 24 XX : mov QWORD PTR [rsp + XX], r9926 case 0x2444894c: // 4c 89 44 24 XX : mov QWORD PTR [rsp + XX], r8927 case 0x244c8944: // 44 89 4c 24 XX mov DWORD PTR [rsp + XX], r9d928 case 0x24448944: // 44 89 44 24 XX mov DWORD PTR [rsp + XX], r8d929 case 0x246c8d48: // 48 8d 6c 24 XX : lea rbp, [rsp + XX]930 return 5;931 case 0x24648348: // 48 83 64 24 XX YY : and QWORD PTR [rsp + XX], YY932 return 6;933 case 0x24A48D48: // 48 8D A4 24 XX XX XX XX : lea rsp, [rsp + XX XX XX XX]934 return 8;935 }936 937 switch (0xFFFFFFFFFFULL & *(u64 *)(address)) {938 case 0xC07E0F4866: // 66 48 0F 7E C0 : movq rax, xmm0939 return 5;940 }941 942#else943 944 switch (*(u8*)address) {945 case 0xA1: // A1 XX XX XX XX : mov eax, dword ptr ds:[XXXXXXXX]946 return 5;947 }948 switch (*(u16*)address) {949 case 0x458B: // 8B 45 XX : mov eax, dword ptr [ebp + XX]950 case 0x5D8B: // 8B 5D XX : mov ebx, dword ptr [ebp + XX]951 case 0x7D8B: // 8B 7D XX : mov edi, dword ptr [ebp + XX]952 case 0x758B: // 8B 75 XX : mov esi, dword ptr [ebp + XX]953 case 0x75FF: // FF 75 XX : push dword ptr [ebp + XX]954 return 3;955 case 0xC1F7: // F7 C1 XX YY ZZ WW : test ecx, WWZZYYXX956 return 6;957 case 0x3D83: // 83 3D XX YY ZZ WW TT : cmp TT, WWZZYYXX958 return 7;959 case 0x7D83: // 83 7D XX YY : cmp dword ptr [ebp + XX], YY960 return 4;961 }962 963 switch (0x00FFFFFF & *(u32*)address) {964 case 0x24448A: // 8A 44 24 XX : mov eal, dword ptr [esp + XX]965 case 0x24448B: // 8B 44 24 XX : mov eax, dword ptr [esp + XX]966 case 0x244C8B: // 8B 4C 24 XX : mov ecx, dword ptr [esp + XX]967 case 0x24548B: // 8B 54 24 XX : mov edx, dword ptr [esp + XX]968 case 0x245C8B: // 8B 5C 24 XX : mov ebx, dword ptr [esp + XX]969 case 0x246C8B: // 8B 6C 24 XX : mov ebp, dword ptr [esp + XX]970 case 0x24748B: // 8B 74 24 XX : mov esi, dword ptr [esp + XX]971 case 0x247C8B: // 8B 7C 24 XX : mov edi, dword ptr [esp + XX]972 return 4;973 }974 975 switch (*(u32*)address) {976 case 0x2444B60F: // 0F B6 44 24 XX : movzx eax, byte ptr [esp + XX]977 return 5;978 }979#endif980 981 // Unknown instruction! This might happen when we add a new interceptor, use982 // a new compiler version, or if Windows changed how some functions are983 // compiled. In either case, we print the address and 8 bytes of instructions984 // to notify the user about the error and to help identify the unknown985 // instruction. Don't treat this as a fatal error, though we can break the986 // debugger if one has been attached.987 u8 *bytes = (u8 *)address;988 ReportError(989 "interception_win: unhandled instruction at %p: %02x %02x %02x %02x %02x "990 "%02x %02x %02x\n",991 (void *)address, bytes[0], bytes[1], bytes[2], bytes[3], bytes[4],992 bytes[5], bytes[6], bytes[7]);993 if (::IsDebuggerPresent())994 __debugbreak();995 return 0;996}997 998size_t TestOnlyGetInstructionSize(uptr address, size_t *rel_offset) {999 return GetInstructionSize(address, rel_offset);1000}1001 1002// Returns 0 on error.1003static size_t RoundUpToInstrBoundary(size_t size, uptr address) {1004 size_t cursor = 0;1005 while (cursor < size) {1006 size_t instruction_size = GetInstructionSize(address + cursor);1007 if (!instruction_size)1008 return 0;1009 cursor += instruction_size;1010 }1011 return cursor;1012}1013 1014static bool CopyInstructions(uptr to, uptr from, size_t size) {1015 size_t cursor = 0;1016 while (cursor != size) {1017 size_t rel_offset = 0;1018 size_t instruction_size = GetInstructionSize(from + cursor, &rel_offset);1019 if (!instruction_size)1020 return false;1021 _memcpy((void *)(to + cursor), (void *)(from + cursor),1022 (size_t)instruction_size);1023 if (rel_offset) {1024# if SANITIZER_WINDOWS641025 // we want to make sure that the new relative offset still fits in 32-bits1026 // this will be untrue if relocated_offset \notin [-2**31, 2**31)1027 s64 delta = to - from;1028 s64 relocated_offset = *(s32 *)(to + cursor + rel_offset) - delta;1029 if (-0x8000'0000ll > relocated_offset ||1030 relocated_offset > 0x7FFF'FFFFll) {1031 ReportError(1032 "interception_win: CopyInstructions relocated_offset %lld outside "1033 "32-bit range\n",1034 (long long)relocated_offset);1035 return false;1036 }1037# else1038 // on 32-bit, the relative offset will always be correct1039 s32 delta = to - from;1040 s32 relocated_offset = *(s32 *)(to + cursor + rel_offset) - delta;1041# endif1042 *(s32 *)(to + cursor + rel_offset) = relocated_offset;1043 }1044 cursor += instruction_size;1045 }1046 return true;1047}1048 1049 1050#if !SANITIZER_WINDOWS641051bool OverrideFunctionWithDetour(1052 uptr old_func, uptr new_func, uptr *orig_old_func) {1053 const int kDetourHeaderLen = 5;1054 const u16 kDetourInstruction = 0xFF8B;1055 1056 uptr header = (uptr)old_func - kDetourHeaderLen;1057 uptr patch_length = kDetourHeaderLen + kShortJumpInstructionLength;1058 1059 // Validate that the function is hookable.1060 if (*(u16*)old_func != kDetourInstruction ||1061 !IsMemoryPadding(header, kDetourHeaderLen))1062 return false;1063 1064 // Change memory protection to writable.1065 DWORD protection = 0;1066 if (!ChangeMemoryProtection(header, patch_length, &protection))1067 return false;1068 1069 // Write a relative jump to the redirected function.1070 WriteJumpInstruction(header, new_func);1071 1072 // Write the short jump to the function prefix.1073 WriteShortJumpInstruction(old_func, header);1074 1075 // Restore previous memory protection.1076 if (!RestoreMemoryProtection(header, patch_length, protection))1077 return false;1078 1079 if (orig_old_func)1080 *orig_old_func = old_func + kShortJumpInstructionLength;1081 1082 return true;1083}1084#endif1085 1086bool OverrideFunctionWithRedirectJump(1087 uptr old_func, uptr new_func, uptr *orig_old_func) {1088 // Check whether the first instruction is a relative jump.1089 if (*(u8*)old_func != 0xE9)1090 return false;1091 1092 if (orig_old_func) {1093 sptr relative_offset = *(s32 *)(old_func + 1);1094 uptr absolute_target = old_func + relative_offset + kJumpInstructionLength;1095 *orig_old_func = absolute_target;1096 }1097 1098#if SANITIZER_WINDOWS641099 // If needed, get memory space for a trampoline jump.1100 uptr trampoline = AllocateMemoryForTrampoline(old_func, kDirectBranchLength);1101 if (!trampoline)1102 return false;1103 WriteDirectBranch(trampoline, new_func);1104#endif1105 1106 // Change memory protection to writable.1107 DWORD protection = 0;1108 if (!ChangeMemoryProtection(old_func, kJumpInstructionLength, &protection))1109 return false;1110 1111 // Write a relative jump to the redirected function.1112 WriteJumpInstruction(old_func, FIRST_32_SECOND_64(new_func, trampoline));1113 1114 // Restore previous memory protection.1115 if (!RestoreMemoryProtection(old_func, kJumpInstructionLength, protection))1116 return false;1117 1118 return true;1119}1120 1121bool OverrideFunctionWithHotPatch(1122 uptr old_func, uptr new_func, uptr *orig_old_func) {1123 const int kHotPatchHeaderLen = kBranchLength;1124 1125 uptr header = (uptr)old_func - kHotPatchHeaderLen;1126 uptr patch_length = kHotPatchHeaderLen + kShortJumpInstructionLength;1127 1128 // Validate that the function is hot patchable.1129 size_t instruction_size = GetInstructionSize(old_func);1130 if (instruction_size < kShortJumpInstructionLength ||1131 !FunctionHasPadding(old_func, kHotPatchHeaderLen))1132 return false;1133 1134 if (orig_old_func) {1135 // Put the needed instructions into the trampoline bytes.1136 uptr trampoline_length = instruction_size + kDirectBranchLength;1137 uptr trampoline = AllocateMemoryForTrampoline(old_func, trampoline_length);1138 if (!trampoline)1139 return false;1140 if (!CopyInstructions(trampoline, old_func, instruction_size))1141 return false;1142 WriteDirectBranch(trampoline + instruction_size,1143 old_func + instruction_size);1144 *orig_old_func = trampoline;1145 }1146 1147 // If needed, get memory space for indirect address.1148 uptr indirect_address = 0;1149#if SANITIZER_WINDOWS641150 indirect_address = AllocateMemoryForTrampoline(old_func, kAddressLength);1151 if (!indirect_address)1152 return false;1153#endif1154 1155 // Change memory protection to writable.1156 DWORD protection = 0;1157 if (!ChangeMemoryProtection(header, patch_length, &protection))1158 return false;1159 1160 // Write jumps to the redirected function.1161 WriteBranch(header, indirect_address, new_func);1162 WriteShortJumpInstruction(old_func, header);1163 1164 // Restore previous memory protection.1165 if (!RestoreMemoryProtection(header, patch_length, protection))1166 return false;1167 1168 return true;1169}1170 1171bool OverrideFunctionWithTrampoline(1172 uptr old_func, uptr new_func, uptr *orig_old_func) {1173 1174 size_t instructions_length = kBranchLength;1175 size_t padding_length = 0;1176 uptr indirect_address = 0;1177 1178 if (orig_old_func) {1179 // Find out the number of bytes of the instructions we need to copy1180 // to the trampoline.1181 instructions_length = RoundUpToInstrBoundary(kBranchLength, old_func);1182 if (!instructions_length)1183 return false;1184 1185 // Put the needed instructions into the trampoline bytes.1186 uptr trampoline_length = instructions_length + kDirectBranchLength;1187 uptr trampoline = AllocateMemoryForTrampoline(old_func, trampoline_length);1188 if (!trampoline)1189 return false;1190 if (!CopyInstructions(trampoline, old_func, instructions_length))1191 return false;1192 WriteDirectBranch(trampoline + instructions_length,1193 old_func + instructions_length);1194 *orig_old_func = trampoline;1195 }1196 1197#if SANITIZER_WINDOWS641198 // Check if the targeted address can be encoded in the function padding.1199 // Otherwise, allocate it in the trampoline region.1200 if (IsMemoryPadding(old_func - kAddressLength, kAddressLength)) {1201 indirect_address = old_func - kAddressLength;1202 padding_length = kAddressLength;1203 } else {1204 indirect_address = AllocateMemoryForTrampoline(old_func, kAddressLength);1205 if (!indirect_address)1206 return false;1207 }1208#endif1209 1210 // Change memory protection to writable.1211 uptr patch_address = old_func - padding_length;1212 uptr patch_length = instructions_length + padding_length;1213 DWORD protection = 0;1214 if (!ChangeMemoryProtection(patch_address, patch_length, &protection))1215 return false;1216 1217 // Patch the original function.1218 WriteBranch(old_func, indirect_address, new_func);1219 1220 // Restore previous memory protection.1221 if (!RestoreMemoryProtection(patch_address, patch_length, protection))1222 return false;1223 1224 return true;1225}1226 1227bool OverrideFunction(1228 uptr old_func, uptr new_func, uptr *orig_old_func) {1229#if !SANITIZER_WINDOWS641230 if (OverrideFunctionWithDetour(old_func, new_func, orig_old_func))1231 return true;1232#endif1233 if (OverrideFunctionWithRedirectJump(old_func, new_func, orig_old_func))1234 return true;1235 if (OverrideFunctionWithHotPatch(old_func, new_func, orig_old_func))1236 return true;1237 if (OverrideFunctionWithTrampoline(old_func, new_func, orig_old_func))1238 return true;1239 return false;1240}1241 1242static void **InterestingDLLsAvailable() {1243 static const char *InterestingDLLs[] = {1244 "kernel32.dll",1245 "msvcr100d.dll", // VS20101246 "msvcr110d.dll", // VS20121247 "msvcr120d.dll", // VS20131248 "vcruntime140d.dll", // VS20151249 "ucrtbased.dll", // Universal CRT1250 "msvcr100.dll", // VS20101251 "msvcr110.dll", // VS20121252 "msvcr120.dll", // VS20131253 "vcruntime140.dll", // VS20151254 "ucrtbase.dll", // Universal CRT1255# if (defined(__MINGW32__) && defined(__i386__))1256 "libc++.dll", // libc++1257 "libunwind.dll", // libunwind1258# endif1259 // NTDLL must go last as it gets special treatment in OverrideFunction.1260 "ntdll.dll",1261 NULL1262 };1263 static void *result[ARRAY_SIZE(InterestingDLLs)] = { 0 };1264 if (!result[0]) {1265 for (size_t i = 0, j = 0; InterestingDLLs[i]; ++i) {1266 if (HMODULE h = GetModuleHandleA(InterestingDLLs[i]))1267 result[j++] = (void *)h;1268 }1269 }1270 return &result[0];1271}1272 1273namespace {1274// Utility for reading loaded PE images.1275template <typename T> class RVAPtr {1276 public:1277 RVAPtr(void *module, uptr rva)1278 : ptr_(reinterpret_cast<T *>(reinterpret_cast<char *>(module) + rva)) {}1279 operator T *() { return ptr_; }1280 T *operator->() { return ptr_; }1281 T *operator++() { return ++ptr_; }1282 1283 private:1284 T *ptr_;1285};1286} // namespace1287 1288// Internal implementation of GetProcAddress. At least since Windows 8,1289// GetProcAddress appears to initialize DLLs before returning function pointers1290// into them. This is problematic for the sanitizers, because they typically1291// want to intercept malloc *before* MSVCRT initializes. Our internal1292// implementation walks the export list manually without doing initialization.1293uptr InternalGetProcAddress(void *module, const char *func_name) {1294 // Check that the module header is full and present.1295 RVAPtr<IMAGE_DOS_HEADER> dos_stub(module, 0);1296 RVAPtr<IMAGE_NT_HEADERS> headers(module, dos_stub->e_lfanew);1297 if (!module || dos_stub->e_magic != IMAGE_DOS_SIGNATURE || // "MZ"1298 headers->Signature != IMAGE_NT_SIGNATURE || // "PE\0\0"1299 headers->FileHeader.SizeOfOptionalHeader <1300 sizeof(IMAGE_OPTIONAL_HEADER)) {1301 return 0;1302 }1303 1304 IMAGE_DATA_DIRECTORY *export_directory =1305 &headers->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT];1306 if (export_directory->Size == 0)1307 return 0;1308 RVAPtr<IMAGE_EXPORT_DIRECTORY> exports(module,1309 export_directory->VirtualAddress);1310 RVAPtr<DWORD> functions(module, exports->AddressOfFunctions);1311 RVAPtr<DWORD> names(module, exports->AddressOfNames);1312 RVAPtr<WORD> ordinals(module, exports->AddressOfNameOrdinals);1313 1314 for (DWORD i = 0; i < exports->NumberOfNames; i++) {1315 RVAPtr<char> name(module, names[i]);1316 if (!_strcmp(func_name, name)) {1317 DWORD index = ordinals[i];1318 RVAPtr<char> func(module, functions[index]);1319 1320 // Handle forwarded functions.1321 DWORD offset = functions[index];1322 if (offset >= export_directory->VirtualAddress &&1323 offset < export_directory->VirtualAddress + export_directory->Size) {1324 // An entry for a forwarded function is a string with the following1325 // format: "<module> . <function_name>" that is stored into the1326 // exported directory.1327 char function_name[256];1328 size_t funtion_name_length = _strlen(func);1329 if (funtion_name_length >= sizeof(function_name) - 1) {1330 ReportError("interception_win: func too long: '%s'\n", (char *)func);1331 InterceptionFailed();1332 }1333 1334 _memcpy(function_name, func, funtion_name_length);1335 function_name[funtion_name_length] = '\0';1336 char* separator = _strchr(function_name, '.');1337 if (!separator) {1338 ReportError("interception_win: no separator in '%s'\n",1339 function_name);1340 InterceptionFailed();1341 }1342 *separator = '\0';1343 1344 void* redirected_module = GetModuleHandleA(function_name);1345 if (!redirected_module) {1346 ReportError("interception_win: GetModuleHandleA failed for '%s'\n",1347 function_name);1348 InterceptionFailed();1349 }1350 return InternalGetProcAddress(redirected_module, separator + 1);1351 }1352 1353 return (uptr)(char *)func;1354 }1355 }1356 1357 return 0;1358}1359 1360bool OverrideFunction(1361 const char *func_name, uptr new_func, uptr *orig_old_func) {1362 static const char *kNtDllIgnore[] = {1363 "memcmp", "memcpy", "memmove", "memset"1364 };1365 1366 bool hooked = false;1367 void **DLLs = InterestingDLLsAvailable();1368 for (size_t i = 0; DLLs[i]; ++i) {1369 if (DLLs[i + 1] == nullptr) {1370 // This is the last DLL, i.e. NTDLL. It exports some functions that1371 // we only want to override in the CRT.1372 for (const char *ignored : kNtDllIgnore) {1373 if (_strcmp(func_name, ignored) == 0)1374 return hooked;1375 }1376 }1377 1378 uptr func_addr = InternalGetProcAddress(DLLs[i], func_name);1379 if (func_addr &&1380 OverrideFunction(func_addr, new_func, orig_old_func)) {1381 hooked = true;1382 }1383 }1384 return hooked;1385}1386 1387bool OverrideImportedFunction(const char *module_to_patch,1388 const char *imported_module,1389 const char *function_name, uptr new_function,1390 uptr *orig_old_func) {1391 HMODULE module = GetModuleHandleA(module_to_patch);1392 if (!module)1393 return false;1394 1395 // Check that the module header is full and present.1396 RVAPtr<IMAGE_DOS_HEADER> dos_stub(module, 0);1397 RVAPtr<IMAGE_NT_HEADERS> headers(module, dos_stub->e_lfanew);1398 if (!module || dos_stub->e_magic != IMAGE_DOS_SIGNATURE || // "MZ"1399 headers->Signature != IMAGE_NT_SIGNATURE || // "PE\0\0"1400 headers->FileHeader.SizeOfOptionalHeader <1401 sizeof(IMAGE_OPTIONAL_HEADER)) {1402 return false;1403 }1404 1405 IMAGE_DATA_DIRECTORY *import_directory =1406 &headers->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT];1407 1408 // Iterate the list of imported DLLs. FirstThunk will be null for the last1409 // entry.1410 RVAPtr<IMAGE_IMPORT_DESCRIPTOR> imports(module,1411 import_directory->VirtualAddress);1412 for (; imports->FirstThunk != 0; ++imports) {1413 RVAPtr<const char> modname(module, imports->Name);1414 if (_stricmp(&*modname, imported_module) == 0)1415 break;1416 }1417 if (imports->FirstThunk == 0)1418 return false;1419 1420 // We have two parallel arrays: the import address table (IAT) and the table1421 // of names. They start out containing the same data, but the loader rewrites1422 // the IAT to hold imported addresses and leaves the name table in1423 // OriginalFirstThunk alone.1424 RVAPtr<IMAGE_THUNK_DATA> name_table(module, imports->OriginalFirstThunk);1425 RVAPtr<IMAGE_THUNK_DATA> iat(module, imports->FirstThunk);1426 for (; name_table->u1.Ordinal != 0; ++name_table, ++iat) {1427 if (!IMAGE_SNAP_BY_ORDINAL(name_table->u1.Ordinal)) {1428 RVAPtr<IMAGE_IMPORT_BY_NAME> import_by_name(1429 module, name_table->u1.ForwarderString);1430 const char *funcname = &import_by_name->Name[0];1431 if (_strcmp(funcname, function_name) == 0)1432 break;1433 }1434 }1435 if (name_table->u1.Ordinal == 0)1436 return false;1437 1438 // Now we have the correct IAT entry. Do the swap. We have to make the page1439 // read/write first.1440 if (orig_old_func)1441 *orig_old_func = iat->u1.AddressOfData;1442 DWORD old_prot, unused_prot;1443 if (!VirtualProtect(&iat->u1.AddressOfData, 4, PAGE_EXECUTE_READWRITE,1444 &old_prot))1445 return false;1446 iat->u1.AddressOfData = new_function;1447 if (!VirtualProtect(&iat->u1.AddressOfData, 4, old_prot, &unused_prot))1448 return false; // Not clear if this failure bothers us.1449 return true;1450}1451 1452} // namespace __interception1453 1454#endif // SANITIZER_WINDOWS1455