12385cf66SAlexandre Ganea //===-- interception_win.cpp ------------------------------------*- C++ -*-===// 2ebbce04cSNico Weber // 3ebbce04cSNico Weber // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4ebbce04cSNico Weber // See https://llvm.org/LICENSE.txt for license information. 5ebbce04cSNico Weber // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6ebbce04cSNico Weber // 7ebbce04cSNico Weber //===----------------------------------------------------------------------===// 8ebbce04cSNico Weber // 9ebbce04cSNico Weber // This file is a part of AddressSanitizer, an address sanity checker. 10ebbce04cSNico Weber // 11ebbce04cSNico Weber // Windows-specific interception methods. 12ebbce04cSNico Weber // 13ebbce04cSNico Weber // This file is implementing several hooking techniques to intercept calls 14ebbce04cSNico Weber // to functions. The hooks are dynamically installed by modifying the assembly 15ebbce04cSNico Weber // code. 16ebbce04cSNico Weber // 17ebbce04cSNico Weber // The hooking techniques are making assumptions on the way the code is 18ebbce04cSNico Weber // generated and are safe under these assumptions. 19ebbce04cSNico Weber // 20ebbce04cSNico Weber // On 64-bit architecture, there is no direct 64-bit jump instruction. To allow 21ebbce04cSNico Weber // arbitrary branching on the whole memory space, the notion of trampoline 22ebbce04cSNico Weber // region is used. A trampoline region is a memory space withing 2G boundary 23ebbce04cSNico Weber // where it is safe to add custom assembly code to build 64-bit jumps. 24ebbce04cSNico Weber // 25ebbce04cSNico Weber // Hooking techniques 26ebbce04cSNico Weber // ================== 27ebbce04cSNico Weber // 28ebbce04cSNico Weber // 1) Detour 29ebbce04cSNico Weber // 3004ccbe6eSHans Wennborg // The Detour hooking technique is assuming the presence of a header with 31ebbce04cSNico Weber // padding and an overridable 2-bytes nop instruction (mov edi, edi). The 32ebbce04cSNico Weber // nop instruction can safely be replaced by a 2-bytes jump without any need 33ebbce04cSNico Weber // to save the instruction. A jump to the target is encoded in the function 34ebbce04cSNico Weber // header and the nop instruction is replaced by a short jump to the header. 35ebbce04cSNico Weber // 36ebbce04cSNico Weber // head: 5 x nop head: jmp <hook> 37ebbce04cSNico Weber // func: mov edi, edi --> func: jmp short <head> 38ebbce04cSNico Weber // [...] real: [...] 39ebbce04cSNico Weber // 40ebbce04cSNico Weber // This technique is only implemented on 32-bit architecture. 41ebbce04cSNico Weber // Most of the time, Windows API are hookable with the detour technique. 42ebbce04cSNico Weber // 43ebbce04cSNico Weber // 2) Redirect Jump 44ebbce04cSNico Weber // 45ebbce04cSNico Weber // The redirect jump is applicable when the first instruction is a direct 46ebbce04cSNico Weber // jump. The instruction is replaced by jump to the hook. 47ebbce04cSNico Weber // 48ebbce04cSNico Weber // func: jmp <label> --> func: jmp <hook> 49ebbce04cSNico Weber // 5004ccbe6eSHans Wennborg // On a 64-bit architecture, a trampoline is inserted. 51ebbce04cSNico Weber // 52ebbce04cSNico Weber // func: jmp <label> --> func: jmp <tramp> 53ebbce04cSNico Weber // [...] 54ebbce04cSNico Weber // 55ebbce04cSNico Weber // [trampoline] 56ebbce04cSNico Weber // tramp: jmp QWORD [addr] 57ebbce04cSNico Weber // addr: .bytes <hook> 58ebbce04cSNico Weber // 59a1e7e401SKazuaki Ishizaki // Note: <real> is equivalent to <label>. 60ebbce04cSNico Weber // 61ebbce04cSNico Weber // 3) HotPatch 62ebbce04cSNico Weber // 6304ccbe6eSHans Wennborg // The HotPatch hooking is assuming the presence of a header with padding 64ebbce04cSNico Weber // and a first instruction with at least 2-bytes. 65ebbce04cSNico Weber // 66ebbce04cSNico Weber // The reason to enforce the 2-bytes limitation is to provide the minimal 67ebbce04cSNico Weber // space to encode a short jump. HotPatch technique is only rewriting one 68ebbce04cSNico Weber // instruction to avoid breaking a sequence of instructions containing a 69ebbce04cSNico Weber // branching target. 70ebbce04cSNico Weber // 71ebbce04cSNico Weber // Assumptions are enforced by MSVC compiler by using the /HOTPATCH flag. 72ebbce04cSNico Weber // see: https://msdn.microsoft.com/en-us/library/ms173507.aspx 73ebbce04cSNico Weber // Default padding length is 5 bytes in 32-bits and 6 bytes in 64-bits. 74ebbce04cSNico Weber // 75ebbce04cSNico Weber // head: 5 x nop head: jmp <hook> 76ebbce04cSNico Weber // func: <instr> --> func: jmp short <head> 77ebbce04cSNico Weber // [...] body: [...] 78ebbce04cSNico Weber // 79ebbce04cSNico Weber // [trampoline] 80ebbce04cSNico Weber // real: <instr> 81ebbce04cSNico Weber // jmp <body> 82ebbce04cSNico Weber // 8304ccbe6eSHans Wennborg // On a 64-bit architecture: 84ebbce04cSNico Weber // 85ebbce04cSNico Weber // head: 6 x nop head: jmp QWORD [addr1] 86ebbce04cSNico Weber // func: <instr> --> func: jmp short <head> 87ebbce04cSNico Weber // [...] body: [...] 88ebbce04cSNico Weber // 89ebbce04cSNico Weber // [trampoline] 90ebbce04cSNico Weber // addr1: .bytes <hook> 91ebbce04cSNico Weber // real: <instr> 92ebbce04cSNico Weber // jmp QWORD [addr2] 93ebbce04cSNico Weber // addr2: .bytes <body> 94ebbce04cSNico Weber // 95ebbce04cSNico Weber // 4) Trampoline 96ebbce04cSNico Weber // 97ebbce04cSNico Weber // The Trampoline hooking technique is the most aggressive one. It is 98ebbce04cSNico Weber // assuming that there is a sequence of instructions that can be safely 99ebbce04cSNico Weber // replaced by a jump (enough room and no incoming branches). 100ebbce04cSNico Weber // 101ebbce04cSNico Weber // Unfortunately, these assumptions can't be safely presumed and code may 102ebbce04cSNico Weber // be broken after hooking. 103ebbce04cSNico Weber // 104ebbce04cSNico Weber // func: <instr> --> func: jmp <hook> 105ebbce04cSNico Weber // <instr> 106ebbce04cSNico Weber // [...] body: [...] 107ebbce04cSNico Weber // 108ebbce04cSNico Weber // [trampoline] 109ebbce04cSNico Weber // real: <instr> 110ebbce04cSNico Weber // <instr> 111ebbce04cSNico Weber // jmp <body> 112ebbce04cSNico Weber // 11304ccbe6eSHans Wennborg // On a 64-bit architecture: 114ebbce04cSNico Weber // 115ebbce04cSNico Weber // func: <instr> --> func: jmp QWORD [addr1] 116ebbce04cSNico Weber // <instr> 117ebbce04cSNico Weber // [...] body: [...] 118ebbce04cSNico Weber // 119ebbce04cSNico Weber // [trampoline] 120ebbce04cSNico Weber // addr1: .bytes <hook> 121ebbce04cSNico Weber // real: <instr> 122ebbce04cSNico Weber // <instr> 123ebbce04cSNico Weber // jmp QWORD [addr2] 124ebbce04cSNico Weber // addr2: .bytes <body> 125ebbce04cSNico Weber //===----------------------------------------------------------------------===// 126ebbce04cSNico Weber 127ebbce04cSNico Weber #include "interception.h" 128ebbce04cSNico Weber 129ebbce04cSNico Weber #if SANITIZER_WINDOWS 130ebbce04cSNico Weber #include "sanitizer_common/sanitizer_platform.h" 131ebbce04cSNico Weber #define WIN32_LEAN_AND_MEAN 132ebbce04cSNico Weber #include <windows.h> 1333d2925b9SHans #include <psapi.h> 134ebbce04cSNico Weber 135ebbce04cSNico Weber namespace __interception { 136ebbce04cSNico Weber 137ebbce04cSNico Weber static const int kAddressLength = FIRST_32_SECOND_64(4, 8); 138ebbce04cSNico Weber static const int kJumpInstructionLength = 5; 139ebbce04cSNico Weber static const int kShortJumpInstructionLength = 2; 140979c38ccSMartin Storsjö UNUSED static const int kIndirectJumpInstructionLength = 6; 141ebbce04cSNico Weber static const int kBranchLength = 142ebbce04cSNico Weber FIRST_32_SECOND_64(kJumpInstructionLength, kIndirectJumpInstructionLength); 143ebbce04cSNico Weber static const int kDirectBranchLength = kBranchLength + kAddressLength; 144ebbce04cSNico Weber 1450716888dSAlvin Wong # if defined(_MSC_VER) 1460716888dSAlvin Wong # define INTERCEPTION_FORMAT(f, a) 1470716888dSAlvin Wong # else 1480716888dSAlvin Wong # define INTERCEPTION_FORMAT(f, a) __attribute__((format(printf, f, a))) 1490716888dSAlvin Wong # endif 1500716888dSAlvin Wong 1510716888dSAlvin Wong static void (*ErrorReportCallback)(const char *format, ...) 1520716888dSAlvin Wong INTERCEPTION_FORMAT(1, 2); 1530716888dSAlvin Wong 1540716888dSAlvin Wong void SetErrorReportCallback(void (*callback)(const char *format, ...)) { 1550716888dSAlvin Wong ErrorReportCallback = callback; 1560716888dSAlvin Wong } 1570716888dSAlvin Wong 1580716888dSAlvin Wong # define ReportError(...) \ 1590716888dSAlvin Wong do { \ 1600716888dSAlvin Wong if (ErrorReportCallback) \ 1610716888dSAlvin Wong ErrorReportCallback(__VA_ARGS__); \ 1620716888dSAlvin Wong } while (0) 1630716888dSAlvin Wong 164ebbce04cSNico Weber static void InterceptionFailed() { 1650716888dSAlvin Wong ReportError("interception_win: failed due to an unrecoverable error.\n"); 1667b5571f3SAlvin Wong // This acts like an abort when no debugger is attached. According to an old 1677b5571f3SAlvin Wong // comment, calling abort() leads to an infinite recursion in CheckFailed. 168ebbce04cSNico Weber __debugbreak(); 169ebbce04cSNico Weber } 170ebbce04cSNico Weber 171ebbce04cSNico Weber static bool DistanceIsWithin2Gig(uptr from, uptr target) { 172ebbce04cSNico Weber #if SANITIZER_WINDOWS64 173ebbce04cSNico Weber if (from < target) 174ebbce04cSNico Weber return target - from <= (uptr)0x7FFFFFFFU; 175ebbce04cSNico Weber else 176ebbce04cSNico Weber return from - target <= (uptr)0x80000000U; 177ebbce04cSNico Weber #else 178ebbce04cSNico Weber // In a 32-bit address space, the address calculation will wrap, so this check 179ebbce04cSNico Weber // is unnecessary. 180ebbce04cSNico Weber return true; 181ebbce04cSNico Weber #endif 182ebbce04cSNico Weber } 183ebbce04cSNico Weber 184ebbce04cSNico Weber static uptr GetMmapGranularity() { 185ebbce04cSNico Weber SYSTEM_INFO si; 186ebbce04cSNico Weber GetSystemInfo(&si); 187ebbce04cSNico Weber return si.dwAllocationGranularity; 188ebbce04cSNico Weber } 189ebbce04cSNico Weber 190cdfd4cffSHans UNUSED static uptr RoundDownTo(uptr size, uptr boundary) { 191cdfd4cffSHans return size & ~(boundary - 1); 192cdfd4cffSHans } 193cdfd4cffSHans 19446fe36a4SAlex Richardson UNUSED static uptr RoundUpTo(uptr size, uptr boundary) { 195cdfd4cffSHans return RoundDownTo(size + boundary - 1, boundary); 19646fe36a4SAlex Richardson } 19746fe36a4SAlex Richardson 19846fe36a4SAlex Richardson // FIXME: internal_str* and internal_mem* functions should be moved from the 19946fe36a4SAlex Richardson // ASan sources into interception/. 20046fe36a4SAlex Richardson 20146fe36a4SAlex Richardson static size_t _strlen(const char *str) { 20246fe36a4SAlex Richardson const char* p = str; 20346fe36a4SAlex Richardson while (*p != '\0') ++p; 20446fe36a4SAlex Richardson return p - str; 20546fe36a4SAlex Richardson } 20646fe36a4SAlex Richardson 20746fe36a4SAlex Richardson static char* _strchr(char* str, char c) { 20846fe36a4SAlex Richardson while (*str) { 20946fe36a4SAlex Richardson if (*str == c) 21046fe36a4SAlex Richardson return str; 21146fe36a4SAlex Richardson ++str; 21246fe36a4SAlex Richardson } 21346fe36a4SAlex Richardson return nullptr; 21446fe36a4SAlex Richardson } 21546fe36a4SAlex Richardson 21669ebac7aSHans Wennborg static int _strcmp(const char *s1, const char *s2) { 21769ebac7aSHans Wennborg while (true) { 21869ebac7aSHans Wennborg unsigned c1 = *s1; 21969ebac7aSHans Wennborg unsigned c2 = *s2; 22069ebac7aSHans Wennborg if (c1 != c2) return (c1 < c2) ? -1 : 1; 22169ebac7aSHans Wennborg if (c1 == 0) break; 22269ebac7aSHans Wennborg s1++; 22369ebac7aSHans Wennborg s2++; 22469ebac7aSHans Wennborg } 22569ebac7aSHans Wennborg return 0; 22669ebac7aSHans Wennborg } 22769ebac7aSHans Wennborg 22846fe36a4SAlex Richardson static void _memset(void *p, int value, size_t sz) { 22946fe36a4SAlex Richardson for (size_t i = 0; i < sz; ++i) 23046fe36a4SAlex Richardson ((char*)p)[i] = (char)value; 23146fe36a4SAlex Richardson } 23246fe36a4SAlex Richardson 23346fe36a4SAlex Richardson static void _memcpy(void *dst, void *src, size_t sz) { 23446fe36a4SAlex Richardson char *dst_c = (char*)dst, 23546fe36a4SAlex Richardson *src_c = (char*)src; 23646fe36a4SAlex Richardson for (size_t i = 0; i < sz; ++i) 23746fe36a4SAlex Richardson dst_c[i] = src_c[i]; 23846fe36a4SAlex Richardson } 23946fe36a4SAlex Richardson 240ebbce04cSNico Weber static bool ChangeMemoryProtection( 241ebbce04cSNico Weber uptr address, uptr size, DWORD *old_protection) { 242ebbce04cSNico Weber return ::VirtualProtect((void*)address, size, 243ebbce04cSNico Weber PAGE_EXECUTE_READWRITE, 244ebbce04cSNico Weber old_protection) != FALSE; 245ebbce04cSNico Weber } 246ebbce04cSNico Weber 247ebbce04cSNico Weber static bool RestoreMemoryProtection( 248ebbce04cSNico Weber uptr address, uptr size, DWORD old_protection) { 249ebbce04cSNico Weber DWORD unused; 250ebbce04cSNico Weber return ::VirtualProtect((void*)address, size, 251ebbce04cSNico Weber old_protection, 252ebbce04cSNico Weber &unused) != FALSE; 253ebbce04cSNico Weber } 254ebbce04cSNico Weber 255ebbce04cSNico Weber static bool IsMemoryPadding(uptr address, uptr size) { 256ebbce04cSNico Weber u8* function = (u8*)address; 257ebbce04cSNico Weber for (size_t i = 0; i < size; ++i) 258ebbce04cSNico Weber if (function[i] != 0x90 && function[i] != 0xCC) 259ebbce04cSNico Weber return false; 260ebbce04cSNico Weber return true; 261ebbce04cSNico Weber } 262ebbce04cSNico Weber 263ebbce04cSNico Weber static const u8 kHintNop8Bytes[] = { 264ebbce04cSNico Weber 0x0F, 0x1F, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00 265ebbce04cSNico Weber }; 266ebbce04cSNico Weber 267ebbce04cSNico Weber template<class T> 268ebbce04cSNico Weber static bool FunctionHasPrefix(uptr address, const T &pattern) { 269ebbce04cSNico Weber u8* function = (u8*)address - sizeof(pattern); 270ebbce04cSNico Weber for (size_t i = 0; i < sizeof(pattern); ++i) 271ebbce04cSNico Weber if (function[i] != pattern[i]) 272ebbce04cSNico Weber return false; 273ebbce04cSNico Weber return true; 274ebbce04cSNico Weber } 275ebbce04cSNico Weber 276ebbce04cSNico Weber static bool FunctionHasPadding(uptr address, uptr size) { 277ebbce04cSNico Weber if (IsMemoryPadding(address - size, size)) 278ebbce04cSNico Weber return true; 279ebbce04cSNico Weber if (size <= sizeof(kHintNop8Bytes) && 280ebbce04cSNico Weber FunctionHasPrefix(address, kHintNop8Bytes)) 281ebbce04cSNico Weber return true; 282ebbce04cSNico Weber return false; 283ebbce04cSNico Weber } 284ebbce04cSNico Weber 285ebbce04cSNico Weber static void WritePadding(uptr from, uptr size) { 28646fe36a4SAlex Richardson _memset((void*)from, 0xCC, (size_t)size); 287ebbce04cSNico Weber } 288ebbce04cSNico Weber 289ebbce04cSNico Weber static void WriteJumpInstruction(uptr from, uptr target) { 2901a7a00bdSAlvin Wong if (!DistanceIsWithin2Gig(from + kJumpInstructionLength, target)) { 2911a7a00bdSAlvin Wong ReportError( 2921a7a00bdSAlvin Wong "interception_win: cannot write jmp further than 2GB away, from %p to " 2931a7a00bdSAlvin Wong "%p.\n", 2941a7a00bdSAlvin Wong (void *)from, (void *)target); 295ebbce04cSNico Weber InterceptionFailed(); 2961a7a00bdSAlvin Wong } 297ebbce04cSNico Weber ptrdiff_t offset = target - from - kJumpInstructionLength; 298ebbce04cSNico Weber *(u8*)from = 0xE9; 299ebbce04cSNico Weber *(u32*)(from + 1) = offset; 300ebbce04cSNico Weber } 301ebbce04cSNico Weber 302ebbce04cSNico Weber static void WriteShortJumpInstruction(uptr from, uptr target) { 303ebbce04cSNico Weber sptr offset = target - from - kShortJumpInstructionLength; 304cdfd4cffSHans if (offset < -128 || offset > 127) { 305cdfd4cffSHans ReportError("interception_win: cannot write short jmp from %p to %p\n", 306cdfd4cffSHans (void *)from, (void *)target); 307ebbce04cSNico Weber InterceptionFailed(); 308cdfd4cffSHans } 309ebbce04cSNico Weber *(u8*)from = 0xEB; 310ebbce04cSNico Weber *(u8*)(from + 1) = (u8)offset; 311ebbce04cSNico Weber } 312ebbce04cSNico Weber 313ebbce04cSNico Weber #if SANITIZER_WINDOWS64 314ebbce04cSNico Weber static void WriteIndirectJumpInstruction(uptr from, uptr indirect_target) { 315ebbce04cSNico Weber // jmp [rip + <offset>] = FF 25 <offset> where <offset> is a relative 316ebbce04cSNico Weber // offset. 317ebbce04cSNico Weber // The offset is the distance from then end of the jump instruction to the 318ebbce04cSNico Weber // memory location containing the targeted address. The displacement is still 319ebbce04cSNico Weber // 32-bit in x64, so indirect_target must be located within +/- 2GB range. 320ebbce04cSNico Weber int offset = indirect_target - from - kIndirectJumpInstructionLength; 321ebbce04cSNico Weber if (!DistanceIsWithin2Gig(from + kIndirectJumpInstructionLength, 322ebbce04cSNico Weber indirect_target)) { 3231a7a00bdSAlvin Wong ReportError( 3241a7a00bdSAlvin Wong "interception_win: cannot write indirect jmp with target further than " 3251a7a00bdSAlvin Wong "2GB away, from %p to %p.\n", 3261a7a00bdSAlvin Wong (void *)from, (void *)indirect_target); 327ebbce04cSNico Weber InterceptionFailed(); 328ebbce04cSNico Weber } 329ebbce04cSNico Weber *(u16*)from = 0x25FF; 330ebbce04cSNico Weber *(u32*)(from + 2) = offset; 331ebbce04cSNico Weber } 332ebbce04cSNico Weber #endif 333ebbce04cSNico Weber 334ebbce04cSNico Weber static void WriteBranch( 335ebbce04cSNico Weber uptr from, uptr indirect_target, uptr target) { 336ebbce04cSNico Weber #if SANITIZER_WINDOWS64 337ebbce04cSNico Weber WriteIndirectJumpInstruction(from, indirect_target); 338ebbce04cSNico Weber *(u64*)indirect_target = target; 339ebbce04cSNico Weber #else 340ebbce04cSNico Weber (void)indirect_target; 341ebbce04cSNico Weber WriteJumpInstruction(from, target); 342ebbce04cSNico Weber #endif 343ebbce04cSNico Weber } 344ebbce04cSNico Weber 345ebbce04cSNico Weber static void WriteDirectBranch(uptr from, uptr target) { 346ebbce04cSNico Weber #if SANITIZER_WINDOWS64 347ebbce04cSNico Weber // Emit an indirect jump through immediately following bytes: 348ebbce04cSNico Weber // jmp [rip + kBranchLength] 349ebbce04cSNico Weber // .quad <target> 350ebbce04cSNico Weber WriteBranch(from, from + kBranchLength, target); 351ebbce04cSNico Weber #else 352ebbce04cSNico Weber WriteJumpInstruction(from, target); 353ebbce04cSNico Weber #endif 354ebbce04cSNico Weber } 355ebbce04cSNico Weber 356ebbce04cSNico Weber struct TrampolineMemoryRegion { 357ebbce04cSNico Weber uptr content; 358ebbce04cSNico Weber uptr allocated_size; 359ebbce04cSNico Weber uptr max_size; 360ebbce04cSNico Weber }; 361ebbce04cSNico Weber 362cdfd4cffSHans UNUSED static const uptr kTrampolineRangeLimit = 1ull << 31; // 2 gig 363ebbce04cSNico Weber static const int kMaxTrampolineRegion = 1024; 364ebbce04cSNico Weber static TrampolineMemoryRegion TrampolineRegions[kMaxTrampolineRegion]; 365ebbce04cSNico Weber 366cdfd4cffSHans static void *AllocateTrampolineRegion(uptr min_addr, uptr max_addr, 367cdfd4cffSHans uptr func_addr, size_t granularity) { 368ebbce04cSNico Weber # if SANITIZER_WINDOWS64 369cdfd4cffSHans // Clamp {min,max}_addr to the accessible address space. 370cdfd4cffSHans SYSTEM_INFO system_info; 371cdfd4cffSHans ::GetSystemInfo(&system_info); 372cdfd4cffSHans uptr min_virtual_addr = 373cdfd4cffSHans RoundUpTo((uptr)system_info.lpMinimumApplicationAddress, granularity); 374cdfd4cffSHans uptr max_virtual_addr = 375cdfd4cffSHans RoundDownTo((uptr)system_info.lpMaximumApplicationAddress, granularity); 376cdfd4cffSHans if (min_addr < min_virtual_addr) 377cdfd4cffSHans min_addr = min_virtual_addr; 378cdfd4cffSHans if (max_addr > max_virtual_addr) 379cdfd4cffSHans max_addr = max_virtual_addr; 380ebbce04cSNico Weber 381cdfd4cffSHans // This loop probes the virtual address space to find free memory in the 382cdfd4cffSHans // [min_addr, max_addr] interval. The search starts from func_addr and 383cdfd4cffSHans // proceeds "outwards" towards the interval bounds using two probes, lo_addr 384cdfd4cffSHans // and hi_addr, for addresses lower/higher than func_addr. At each step, it 385cdfd4cffSHans // considers the probe closest to func_addr. If that address is not free, the 386cdfd4cffSHans // probe is advanced (lower or higher depending on the probe) to the next 387cdfd4cffSHans // memory block and the search continues. 388cdfd4cffSHans uptr lo_addr = RoundDownTo(func_addr, granularity); 389cdfd4cffSHans uptr hi_addr = RoundUpTo(func_addr, granularity); 390cdfd4cffSHans while (lo_addr >= min_addr || hi_addr <= max_addr) { 391cdfd4cffSHans // Consider the in-range address closest to func_addr. 392cdfd4cffSHans uptr addr; 393cdfd4cffSHans if (lo_addr < min_addr) 394cdfd4cffSHans addr = hi_addr; 395cdfd4cffSHans else if (hi_addr > max_addr) 396cdfd4cffSHans addr = lo_addr; 397cdfd4cffSHans else 398cdfd4cffSHans addr = (hi_addr - func_addr < func_addr - lo_addr) ? hi_addr : lo_addr; 399cdfd4cffSHans 400cdfd4cffSHans MEMORY_BASIC_INFORMATION info; 401cdfd4cffSHans if (!::VirtualQuery((void *)addr, &info, sizeof(info))) { 402cdfd4cffSHans ReportError( 403cdfd4cffSHans "interception_win: VirtualQuery in AllocateTrampolineRegion failed " 404cdfd4cffSHans "for %p\n", 405cdfd4cffSHans (void *)addr); 406cdfd4cffSHans return nullptr; 407cdfd4cffSHans } 408cdfd4cffSHans 409cdfd4cffSHans // Check whether a region can be allocated at |addr|. 410ebbce04cSNico Weber if (info.State == MEM_FREE && info.RegionSize >= granularity) { 411cdfd4cffSHans void *page = 412cdfd4cffSHans ::VirtualAlloc((void *)addr, granularity, MEM_RESERVE | MEM_COMMIT, 413ebbce04cSNico Weber PAGE_EXECUTE_READWRITE); 414cdfd4cffSHans if (page == nullptr) 415cdfd4cffSHans ReportError( 416cdfd4cffSHans "interception_win: VirtualAlloc in AllocateTrampolineRegion failed " 417cdfd4cffSHans "for %p\n", 418cdfd4cffSHans (void *)addr); 419ebbce04cSNico Weber return page; 420ebbce04cSNico Weber } 421ebbce04cSNico Weber 422cdfd4cffSHans if (addr == lo_addr) 423cdfd4cffSHans lo_addr = 424cdfd4cffSHans RoundDownTo((uptr)info.AllocationBase - granularity, granularity); 425cdfd4cffSHans if (addr == hi_addr) 426cdfd4cffSHans hi_addr = 427cdfd4cffSHans RoundUpTo((uptr)info.BaseAddress + info.RegionSize, granularity); 428ebbce04cSNico Weber } 429cdfd4cffSHans 430cdfd4cffSHans ReportError( 431cdfd4cffSHans "interception_win: AllocateTrampolineRegion failed to find free memory; " 432cdfd4cffSHans "min_addr: %p, max_addr: %p, func_addr: %p, granularity: %zu\n", 433055f1a77Sbernhardu (void *)min_addr, (void *)max_addr, (void *)func_addr, granularity); 434ebbce04cSNico Weber return nullptr; 435ebbce04cSNico Weber #else 436ebbce04cSNico Weber return ::VirtualAlloc(nullptr, 437ebbce04cSNico Weber granularity, 438ebbce04cSNico Weber MEM_RESERVE | MEM_COMMIT, 439ebbce04cSNico Weber PAGE_EXECUTE_READWRITE); 440ebbce04cSNico Weber #endif 441ebbce04cSNico Weber } 442ebbce04cSNico Weber 443ebbce04cSNico Weber // Used by unittests to release mapped memory space. 444ebbce04cSNico Weber void TestOnlyReleaseTrampolineRegions() { 445ebbce04cSNico Weber for (size_t bucket = 0; bucket < kMaxTrampolineRegion; ++bucket) { 446ebbce04cSNico Weber TrampolineMemoryRegion *current = &TrampolineRegions[bucket]; 447ebbce04cSNico Weber if (current->content == 0) 448ebbce04cSNico Weber return; 449ebbce04cSNico Weber ::VirtualFree((void*)current->content, 0, MEM_RELEASE); 450ebbce04cSNico Weber current->content = 0; 451ebbce04cSNico Weber } 452ebbce04cSNico Weber } 453ebbce04cSNico Weber 4543d2925b9SHans static uptr AllocateMemoryForTrampoline(uptr func_address, size_t size) { 4553d2925b9SHans # if SANITIZER_WINDOWS64 456cdfd4cffSHans uptr min_addr = func_address - kTrampolineRangeLimit; 457cdfd4cffSHans uptr max_addr = func_address + kTrampolineRangeLimit - size; 458cdfd4cffSHans 459cdfd4cffSHans // Allocate memory within 2GB of the module (DLL or EXE file) so that any 460cdfd4cffSHans // address within the module can be referenced with PC-relative operands. 4613d2925b9SHans // This allows us to not just jump to the trampoline with a PC-relative 4623d2925b9SHans // offset, but to relocate any instructions that we copy to the trampoline 4633d2925b9SHans // which have references to the original module. If we can't find the base 4643d2925b9SHans // address of the module (e.g. if func_address is in mmap'ed memory), just 465cdfd4cffSHans // stay within 2GB of func_address. 4663d2925b9SHans HMODULE module; 4673d2925b9SHans if (::GetModuleHandleExW(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS | 4683d2925b9SHans GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT, 4693d2925b9SHans (LPCWSTR)func_address, &module)) { 4703d2925b9SHans MODULEINFO module_info; 4713d2925b9SHans if (::GetModuleInformation(::GetCurrentProcess(), module, 4723d2925b9SHans &module_info, sizeof(module_info))) { 473cdfd4cffSHans min_addr = (uptr)module_info.lpBaseOfDll + module_info.SizeOfImage - 474cdfd4cffSHans kTrampolineRangeLimit; 475cdfd4cffSHans max_addr = (uptr)module_info.lpBaseOfDll + kTrampolineRangeLimit - size; 4763d2925b9SHans } 4773d2925b9SHans } 478cdfd4cffSHans 479cdfd4cffSHans // Check for overflow. 480cdfd4cffSHans if (min_addr > func_address) 481cdfd4cffSHans min_addr = 0; 482cdfd4cffSHans if (max_addr < func_address) 483cdfd4cffSHans max_addr = ~(uptr)0; 484cdfd4cffSHans # else 485cdfd4cffSHans uptr min_addr = 0; 486cdfd4cffSHans uptr max_addr = ~min_addr; 4873d2925b9SHans # endif 4883d2925b9SHans 489cdfd4cffSHans // Find a region within [min_addr,max_addr] with enough space to allocate 490cdfd4cffSHans // |size| bytes. 491ebbce04cSNico Weber TrampolineMemoryRegion *region = nullptr; 492ebbce04cSNico Weber for (size_t bucket = 0; bucket < kMaxTrampolineRegion; ++bucket) { 493ebbce04cSNico Weber TrampolineMemoryRegion* current = &TrampolineRegions[bucket]; 494ebbce04cSNico Weber if (current->content == 0) { 495ebbce04cSNico Weber // No valid region found, allocate a new region. 496ebbce04cSNico Weber size_t bucket_size = GetMmapGranularity(); 497cdfd4cffSHans void *content = AllocateTrampolineRegion(min_addr, max_addr, func_address, 498cdfd4cffSHans bucket_size); 499ebbce04cSNico Weber if (content == nullptr) 500ebbce04cSNico Weber return 0U; 501ebbce04cSNico Weber 502ebbce04cSNico Weber current->content = (uptr)content; 503ebbce04cSNico Weber current->allocated_size = 0; 504ebbce04cSNico Weber current->max_size = bucket_size; 505ebbce04cSNico Weber region = current; 506ebbce04cSNico Weber break; 507ebbce04cSNico Weber } else if (current->max_size - current->allocated_size > size) { 508ebbce04cSNico Weber uptr next_address = current->content + current->allocated_size; 509cdfd4cffSHans if (next_address < min_addr || next_address > max_addr) 510ebbce04cSNico Weber continue; 511ebbce04cSNico Weber // The space can be allocated in the current region. 512ebbce04cSNico Weber region = current; 513ebbce04cSNico Weber break; 514ebbce04cSNico Weber } 515ebbce04cSNico Weber } 516ebbce04cSNico Weber 517ebbce04cSNico Weber // Failed to find a region. 518ebbce04cSNico Weber if (region == nullptr) 519ebbce04cSNico Weber return 0U; 520ebbce04cSNico Weber 521ebbce04cSNico Weber // Allocate the space in the current region. 522ebbce04cSNico Weber uptr allocated_space = region->content + region->allocated_size; 523ebbce04cSNico Weber region->allocated_size += size; 524ebbce04cSNico Weber WritePadding(allocated_space, size); 525ebbce04cSNico Weber 526ebbce04cSNico Weber return allocated_space; 527ebbce04cSNico Weber } 528ebbce04cSNico Weber 52922ea0ceaSToshihito Kikuchi // The following prologues cannot be patched because of the short jump 53022ea0ceaSToshihito Kikuchi // jumping to the patching region. 53122ea0ceaSToshihito Kikuchi 532d79aee9fSFarzon Lotfi // Short jump patterns below are only for x86_64. 533d79aee9fSFarzon Lotfi # if SANITIZER_WINDOWS_x64 53422ea0ceaSToshihito Kikuchi // ntdll!wcslen in Win11 53522ea0ceaSToshihito Kikuchi // 488bc1 mov rax,rcx 53622ea0ceaSToshihito Kikuchi // 0fb710 movzx edx,word ptr [rax] 53722ea0ceaSToshihito Kikuchi // 4883c002 add rax,2 53822ea0ceaSToshihito Kikuchi // 6685d2 test dx,dx 53922ea0ceaSToshihito Kikuchi // 75f4 jne -12 54022ea0ceaSToshihito Kikuchi static const u8 kPrologueWithShortJump1[] = { 54122ea0ceaSToshihito Kikuchi 0x48, 0x8b, 0xc1, 0x0f, 0xb7, 0x10, 0x48, 0x83, 54222ea0ceaSToshihito Kikuchi 0xc0, 0x02, 0x66, 0x85, 0xd2, 0x75, 0xf4, 54322ea0ceaSToshihito Kikuchi }; 54422ea0ceaSToshihito Kikuchi 54522ea0ceaSToshihito Kikuchi // ntdll!strrchr in Win11 54622ea0ceaSToshihito Kikuchi // 4c8bc1 mov r8,rcx 54722ea0ceaSToshihito Kikuchi // 8a01 mov al,byte ptr [rcx] 54822ea0ceaSToshihito Kikuchi // 48ffc1 inc rcx 54922ea0ceaSToshihito Kikuchi // 84c0 test al,al 55022ea0ceaSToshihito Kikuchi // 75f7 jne -9 55122ea0ceaSToshihito Kikuchi static const u8 kPrologueWithShortJump2[] = { 55222ea0ceaSToshihito Kikuchi 0x4c, 0x8b, 0xc1, 0x8a, 0x01, 0x48, 0xff, 0xc1, 55322ea0ceaSToshihito Kikuchi 0x84, 0xc0, 0x75, 0xf7, 55422ea0ceaSToshihito Kikuchi }; 555aa45fc41SMartin Storsjö #endif 55622ea0ceaSToshihito Kikuchi 557ebbce04cSNico Weber // Returns 0 on error. 558ebbce04cSNico Weber static size_t GetInstructionSize(uptr address, size_t* rel_offset = nullptr) { 55936b1811dSbernhardu if (rel_offset) { 56036b1811dSbernhardu *rel_offset = 0; 56136b1811dSbernhardu } 56236b1811dSbernhardu 5635a48a824SFarzon Lotfi #if SANITIZER_ARM64 5645a48a824SFarzon Lotfi // An ARM64 instruction is 4 bytes long. 5655a48a824SFarzon Lotfi return 4; 5665a48a824SFarzon Lotfi #endif 5675a48a824SFarzon Lotfi 568d79aee9fSFarzon Lotfi # if SANITIZER_WINDOWS_x64 56922ea0ceaSToshihito Kikuchi if (memcmp((u8*)address, kPrologueWithShortJump1, 57022ea0ceaSToshihito Kikuchi sizeof(kPrologueWithShortJump1)) == 0 || 57122ea0ceaSToshihito Kikuchi memcmp((u8*)address, kPrologueWithShortJump2, 57222ea0ceaSToshihito Kikuchi sizeof(kPrologueWithShortJump2)) == 0) { 57322ea0ceaSToshihito Kikuchi return 0; 57422ea0ceaSToshihito Kikuchi } 57522ea0ceaSToshihito Kikuchi #endif 57622ea0ceaSToshihito Kikuchi 577ebbce04cSNico Weber switch (*(u64*)address) { 578ebbce04cSNico Weber case 0x90909090909006EB: // stub: jmp over 6 x nop. 579ebbce04cSNico Weber return 8; 580ebbce04cSNico Weber } 581ebbce04cSNico Weber 582ebbce04cSNico Weber switch (*(u8*)address) { 583ebbce04cSNico Weber case 0x90: // 90 : nop 58442383242SCharlie Barto case 0xC3: // C3 : ret (for small/empty function interception 58542383242SCharlie Barto case 0xCC: // CC : int 3 i.e. registering weak functions) 586ebbce04cSNico Weber return 1; 587ebbce04cSNico Weber 588ebbce04cSNico Weber case 0x50: // push eax / rax 589ebbce04cSNico Weber case 0x51: // push ecx / rcx 590ebbce04cSNico Weber case 0x52: // push edx / rdx 591ebbce04cSNico Weber case 0x53: // push ebx / rbx 592ebbce04cSNico Weber case 0x54: // push esp / rsp 593ebbce04cSNico Weber case 0x55: // push ebp / rbp 594ebbce04cSNico Weber case 0x56: // push esi / rsi 595ebbce04cSNico Weber case 0x57: // push edi / rdi 596ebbce04cSNico Weber case 0x5D: // pop ebp / rbp 597ebbce04cSNico Weber return 1; 598ebbce04cSNico Weber 599ebbce04cSNico Weber case 0x6A: // 6A XX = push XX 600ebbce04cSNico Weber return 2; 601ebbce04cSNico Weber 6023bd8f4e0SCharlie Barto // This instruction can be encoded with a 16-bit immediate but that is 6033bd8f4e0SCharlie Barto // incredibly unlikely. 6043bd8f4e0SCharlie Barto case 0x68: // 68 XX XX XX XX : push imm32 6053bd8f4e0SCharlie Barto return 5; 6063bd8f4e0SCharlie Barto 607ebbce04cSNico Weber case 0xb8: // b8 XX XX XX XX : mov eax, XX XX XX XX 608ebbce04cSNico Weber case 0xB9: // b9 XX XX XX XX : mov ecx, XX XX XX XX 6095f405707Sbernhardu case 0xBA: // ba XX XX XX XX : mov edx, XX XX XX XX 610ebbce04cSNico Weber return 5; 611ebbce04cSNico Weber 612ebbce04cSNico Weber // Cannot overwrite control-instruction. Return 0 to indicate failure. 613ebbce04cSNico Weber case 0xE9: // E9 XX XX XX XX : jmp <label> 614ebbce04cSNico Weber case 0xE8: // E8 XX XX XX XX : call <func> 615ebbce04cSNico Weber case 0xEB: // EB XX : jmp XX (short jump) 616ebbce04cSNico Weber case 0x70: // 7Y YY : jy XX (short conditional jump) 617ebbce04cSNico Weber case 0x71: 618ebbce04cSNico Weber case 0x72: 619ebbce04cSNico Weber case 0x73: 620ebbce04cSNico Weber case 0x74: 621ebbce04cSNico Weber case 0x75: 622ebbce04cSNico Weber case 0x76: 623ebbce04cSNico Weber case 0x77: 624ebbce04cSNico Weber case 0x78: 625ebbce04cSNico Weber case 0x79: 626ebbce04cSNico Weber case 0x7A: 627ebbce04cSNico Weber case 0x7B: 628ebbce04cSNico Weber case 0x7C: 629ebbce04cSNico Weber case 0x7D: 630ebbce04cSNico Weber case 0x7E: 631ebbce04cSNico Weber case 0x7F: 632ebbce04cSNico Weber return 0; 633ebbce04cSNico Weber } 634ebbce04cSNico Weber 635ebbce04cSNico Weber switch (*(u16*)(address)) { 636ebbce04cSNico Weber case 0x018A: // 8A 01 : mov al, byte ptr [ecx] 637ebbce04cSNico Weber case 0xFF8B: // 8B FF : mov edi, edi 638ebbce04cSNico Weber case 0xEC8B: // 8B EC : mov ebp, esp 639ebbce04cSNico Weber case 0xc889: // 89 C8 : mov eax, ecx 64099612a3aSbernhardu case 0xD189: // 89 D1 : mov ecx, edx 641ca40985eSAlvin Wong case 0xE589: // 89 E5 : mov ebp, esp 642ebbce04cSNico Weber case 0xC18B: // 8B C1 : mov eax, ecx 64399612a3aSbernhardu case 0xC031: // 31 C0 : xor eax, eax 64499612a3aSbernhardu case 0xC931: // 31 C9 : xor ecx, ecx 64599612a3aSbernhardu case 0xD231: // 31 D2 : xor edx, edx 646ebbce04cSNico Weber case 0xC033: // 33 C0 : xor eax, eax 647ebbce04cSNico Weber case 0xC933: // 33 C9 : xor ecx, ecx 648ebbce04cSNico Weber case 0xD233: // 33 D2 : xor edx, edx 6493bd8f4e0SCharlie Barto case 0xDB84: // 84 DB : test bl,bl 65099612a3aSbernhardu case 0xC084: // 84 C0 : test al,al 6513bd8f4e0SCharlie Barto case 0xC984: // 84 C9 : test cl,cl 6523bd8f4e0SCharlie Barto case 0xD284: // 84 D2 : test dl,dl 653ebbce04cSNico Weber return 2; 654ebbce04cSNico Weber 65557466db7Sbernhardu case 0x3980: // 80 39 XX : cmp BYTE PTR [rcx], XX 65657466db7Sbernhardu case 0x4D8B: // 8B 4D XX : mov XX(%ebp), ecx 65757466db7Sbernhardu case 0x558B: // 8B 55 XX : mov XX(%ebp), edx 65857466db7Sbernhardu case 0x758B: // 8B 75 XX : mov XX(%ebp), esp 659f85579fbSbernhardu case 0xE483: // 83 E4 XX : and esp, XX 660854ea0cfSbernhardu case 0xEC83: // 83 EC XX : sub esp, XX 661bf6f1ca2Sbernhardu case 0xC1F6: // F6 C1 XX : test cl, XX 662bf6f1ca2Sbernhardu return 3; 663bf6f1ca2Sbernhardu 664351ee305Sbernhardu case 0x89FF: // FF 89 XX XX XX XX : dec dword ptr [ecx + XX XX XX XX] 665351ee305Sbernhardu case 0xEC81: // 81 EC XX XX XX XX : sub esp, XX XX XX XX 666351ee305Sbernhardu return 6; 667351ee305Sbernhardu 668ebbce04cSNico Weber // Cannot overwrite control-instruction. Return 0 to indicate failure. 669a943922cSbernhardu case 0x25FF: // FF 25 XX YY ZZ WW : jmp dword ptr ds:[WWZZYYXX] 670ebbce04cSNico Weber return 0; 671ebbce04cSNico Weber } 672ebbce04cSNico Weber 673ebbce04cSNico Weber switch (0x00FFFFFF & *(u32 *)address) { 67456592a81Sbernhardu case 0x244C8D: // 8D 4C 24 XX : lea ecx, [esp + XX] 67556592a81Sbernhardu case 0x2474FF: // FF 74 24 XX : push qword ptr [rsp + XX] 67656592a81Sbernhardu return 4; 677ebbce04cSNico Weber case 0x24A48D: // 8D A4 24 XX XX XX XX : lea esp, [esp + XX XX XX XX] 678ebbce04cSNico Weber return 7; 679ebbce04cSNico Weber } 680ebbce04cSNico Weber 68142383242SCharlie Barto switch (0x000000FF & *(u32 *)address) { 68242383242SCharlie Barto case 0xc2: // C2 XX XX : ret XX (needed for registering weak functions) 68342383242SCharlie Barto return 3; 68442383242SCharlie Barto } 68542383242SCharlie Barto 686d79aee9fSFarzon Lotfi # if SANITIZER_WINDOWS_x64 687ebbce04cSNico Weber switch (*(u8*)address) { 688ebbce04cSNico Weber case 0xA1: // A1 XX XX XX XX XX XX XX XX : 689ebbce04cSNico Weber // movabs eax, dword ptr ds:[XXXXXXXX] 690ebbce04cSNico Weber return 9; 6913bd8f4e0SCharlie Barto case 0xF2: 6923bd8f4e0SCharlie Barto switch (*(u32 *)(address + 1)) { 6933bd8f4e0SCharlie Barto case 0x2444110f: // f2 0f 11 44 24 XX movsd QWORD PTR 6943bd8f4e0SCharlie Barto // [rsp + XX], xmm0 6953bd8f4e0SCharlie Barto case 0x244c110f: // f2 0f 11 4c 24 XX movsd QWORD PTR 6963bd8f4e0SCharlie Barto // [rsp + XX], xmm1 6973bd8f4e0SCharlie Barto case 0x2454110f: // f2 0f 11 54 24 XX movsd QWORD PTR 6983bd8f4e0SCharlie Barto // [rsp + XX], xmm2 6993bd8f4e0SCharlie Barto case 0x245c110f: // f2 0f 11 5c 24 XX movsd QWORD PTR 7003bd8f4e0SCharlie Barto // [rsp + XX], xmm3 7013bd8f4e0SCharlie Barto case 0x2464110f: // f2 0f 11 64 24 XX movsd QWORD PTR 7023bd8f4e0SCharlie Barto // [rsp + XX], xmm4 7033bd8f4e0SCharlie Barto return 6; 7043bd8f4e0SCharlie Barto } 7053bd8f4e0SCharlie Barto break; 70622ea0ceaSToshihito Kikuchi 70722ea0ceaSToshihito Kikuchi case 0x83: 70822ea0ceaSToshihito Kikuchi const u8 next_byte = *(u8*)(address + 1); 70922ea0ceaSToshihito Kikuchi const u8 mod = next_byte >> 6; 71022ea0ceaSToshihito Kikuchi const u8 rm = next_byte & 7; 71122ea0ceaSToshihito Kikuchi if (mod == 1 && rm == 4) 71222ea0ceaSToshihito Kikuchi return 5; // 83 ModR/M SIB Disp8 Imm8 71322ea0ceaSToshihito Kikuchi // add|or|adc|sbb|and|sub|xor|cmp [r+disp8], imm8 714ebbce04cSNico Weber } 715ebbce04cSNico Weber 716ebbce04cSNico Weber switch (*(u16*)address) { 717ebbce04cSNico Weber case 0x5040: // push rax 718ebbce04cSNico Weber case 0x5140: // push rcx 719ebbce04cSNico Weber case 0x5240: // push rdx 720ebbce04cSNico Weber case 0x5340: // push rbx 721ebbce04cSNico Weber case 0x5440: // push rsp 722ebbce04cSNico Weber case 0x5540: // push rbp 723ebbce04cSNico Weber case 0x5640: // push rsi 724ebbce04cSNico Weber case 0x5740: // push rdi 725ebbce04cSNico Weber case 0x5441: // push r12 726ebbce04cSNico Weber case 0x5541: // push r13 727ebbce04cSNico Weber case 0x5641: // push r14 728ebbce04cSNico Weber case 0x5741: // push r15 729ebbce04cSNico Weber case 0x9066: // Two-byte NOP 73022ea0ceaSToshihito Kikuchi case 0xc084: // test al, al 73122ea0ceaSToshihito Kikuchi case 0x018a: // mov al, byte ptr [rcx] 732ebbce04cSNico Weber return 2; 733ebbce04cSNico Weber 7343bd8f4e0SCharlie Barto case 0x7E80: // 80 7E YY XX cmp BYTE PTR [rsi+YY], XX 7353bd8f4e0SCharlie Barto case 0x7D80: // 80 7D YY XX cmp BYTE PTR [rbp+YY], XX 7363bd8f4e0SCharlie Barto case 0x7A80: // 80 7A YY XX cmp BYTE PTR [rdx+YY], XX 7373bd8f4e0SCharlie Barto case 0x7880: // 80 78 YY XX cmp BYTE PTR [rax+YY], XX 7383bd8f4e0SCharlie Barto case 0x7B80: // 80 7B YY XX cmp BYTE PTR [rbx+YY], XX 7393bd8f4e0SCharlie Barto case 0x7980: // 80 79 YY XX cmp BYTE ptr [rcx+YY], XX 7403bd8f4e0SCharlie Barto return 4; 7413bd8f4e0SCharlie Barto 7426c52a18aSbernhardu case 0x058A: // 8A 05 XX XX XX XX : mov al, byte ptr [XX XX XX XX] 743ebbce04cSNico Weber case 0x058B: // 8B 05 XX XX XX XX : mov eax, dword ptr [XX XX XX XX] 744ebbce04cSNico Weber if (rel_offset) 745ebbce04cSNico Weber *rel_offset = 2; 746351ee305Sbernhardu case 0xB841: // 41 B8 XX XX XX XX : mov r8d, XX XX XX XX 747ebbce04cSNico Weber return 6; 7483bd8f4e0SCharlie Barto 7493bd8f4e0SCharlie Barto case 0x7E81: // 81 7E YY XX XX XX XX cmp DWORD PTR [rsi+YY], XX XX XX XX 7503bd8f4e0SCharlie Barto case 0x7D81: // 81 7D YY XX XX XX XX cmp DWORD PTR [rbp+YY], XX XX XX XX 7513bd8f4e0SCharlie Barto case 0x7A81: // 81 7A YY XX XX XX XX cmp DWORD PTR [rdx+YY], XX XX XX XX 7523bd8f4e0SCharlie Barto case 0x7881: // 81 78 YY XX XX XX XX cmp DWORD PTR [rax+YY], XX XX XX XX 7533bd8f4e0SCharlie Barto case 0x7B81: // 81 7B YY XX XX XX XX cmp DWORD PTR [rbx+YY], XX XX XX XX 7543bd8f4e0SCharlie Barto case 0x7981: // 81 79 YY XX XX XX XX cmp dword ptr [rcx+YY], XX XX XX XX 7553bd8f4e0SCharlie Barto return 7; 756ebbce04cSNico Weber } 757ebbce04cSNico Weber 758ebbce04cSNico Weber switch (0x00FFFFFF & *(u32 *)address) { 7593bd8f4e0SCharlie Barto case 0x10b70f: // 0f b7 10 : movzx edx, WORD PTR [rax] 7603bd8f4e0SCharlie Barto case 0xc00b4d: // 4d 0b c0 : or r8, r8 761ebbce04cSNico Weber case 0xc03345: // 45 33 c0 : xor r8d, r8d 7623bd8f4e0SCharlie Barto case 0xc08548: // 48 85 c0 : test rax, rax 7633bd8f4e0SCharlie Barto case 0xc0854d: // 4d 85 c0 : test r8, r8 7643bd8f4e0SCharlie Barto case 0xc08b41: // 41 8b c0 : mov eax, r8d 7653bd8f4e0SCharlie Barto case 0xc0ff48: // 48 ff c0 : inc rax 7663bd8f4e0SCharlie Barto case 0xc0ff49: // 49 ff c0 : inc r8 7673bd8f4e0SCharlie Barto case 0xc18b41: // 41 8b c1 : mov eax, r9d 7683bd8f4e0SCharlie Barto case 0xc18b48: // 48 8b c1 : mov rax, rcx 7693bd8f4e0SCharlie Barto case 0xc18b4c: // 4c 8b c1 : mov r8, rcx 7703bd8f4e0SCharlie Barto case 0xc1ff48: // 48 ff c1 : inc rcx 7713bd8f4e0SCharlie Barto case 0xc1ff49: // 49 ff c1 : inc r9 7723bd8f4e0SCharlie Barto case 0xc28b41: // 41 8b c2 : mov eax, r10d 77357466db7Sbernhardu case 0x01b60f: // 0f b6 01 : movzx eax, BYTE PTR [rcx] 77457466db7Sbernhardu case 0x09b60f: // 0f b6 09 : movzx ecx, BYTE PTR [rcx] 77557466db7Sbernhardu case 0x11b60f: // 0f b6 11 : movzx edx, BYTE PTR [rcx] 7763bd8f4e0SCharlie Barto case 0xc2b60f: // 0f b6 c2 : movzx eax, dl 7773bd8f4e0SCharlie Barto case 0xc2ff48: // 48 ff c2 : inc rdx 7783bd8f4e0SCharlie Barto case 0xc2ff49: // 49 ff c2 : inc r10 7793bd8f4e0SCharlie Barto case 0xc38b41: // 41 8b c3 : mov eax, r11d 7803bd8f4e0SCharlie Barto case 0xc3ff48: // 48 ff c3 : inc rbx 7813bd8f4e0SCharlie Barto case 0xc3ff49: // 49 ff c3 : inc r11 7823bd8f4e0SCharlie Barto case 0xc48b41: // 41 8b c4 : mov eax, r12d 7833bd8f4e0SCharlie Barto case 0xc48b48: // 48 8b c4 : mov rax, rsp 7843bd8f4e0SCharlie Barto case 0xc4ff49: // 49 ff c4 : inc r12 7853bd8f4e0SCharlie Barto case 0xc5ff49: // 49 ff c5 : inc r13 7863bd8f4e0SCharlie Barto case 0xc6ff48: // 48 ff c6 : inc rsi 7873bd8f4e0SCharlie Barto case 0xc6ff49: // 49 ff c6 : inc r14 7883bd8f4e0SCharlie Barto case 0xc7ff48: // 48 ff c7 : inc rdi 7893bd8f4e0SCharlie Barto case 0xc7ff49: // 49 ff c7 : inc r15 790ebbce04cSNico Weber case 0xc93345: // 45 33 c9 : xor r9d, r9d 7913bd8f4e0SCharlie Barto case 0xc98548: // 48 85 c9 : test rcx, rcx 7923bd8f4e0SCharlie Barto case 0xc9854d: // 4d 85 c9 : test r9, r9 7933bd8f4e0SCharlie Barto case 0xc98b4c: // 4c 8b c9 : mov r9, rcx 79457466db7Sbernhardu case 0xd12948: // 48 29 d1 : sub rcx, rdx 795ebbce04cSNico Weber case 0xca2b48: // 48 2b ca : sub rcx, rdx 79642383242SCharlie Barto case 0xca3b48: // 48 3b ca : cmp rcx, rdx 7973bd8f4e0SCharlie Barto case 0xd12b48: // 48 2b d1 : sub rdx, rcx 798ebbce04cSNico Weber case 0xd18b48: // 48 8b d1 : mov rdx, rcx 799ebbce04cSNico Weber case 0xd18b4c: // 4c 8b d1 : mov r10, rcx 8003bd8f4e0SCharlie Barto case 0xd28548: // 48 85 d2 : test rdx, rdx 8013bd8f4e0SCharlie Barto case 0xd2854d: // 4d 85 d2 : test r10, r10 8023bd8f4e0SCharlie Barto case 0xd28b4c: // 4c 8b d2 : mov r10, rdx 8033bd8f4e0SCharlie Barto case 0xd2b60f: // 0f b6 d2 : movzx edx, dl 80457466db7Sbernhardu case 0xd2be0f: // 0f be d2 : movsx edx, dl 8053bd8f4e0SCharlie Barto case 0xd98b4c: // 4c 8b d9 : mov r11, rcx 8063bd8f4e0SCharlie Barto case 0xd9f748: // 48 f7 d9 : neg rcx 80757466db7Sbernhardu case 0xc03145: // 45 31 c0 : xor r8d,r8d 80857466db7Sbernhardu case 0xc93145: // 45 31 c9 : xor r9d,r9d 8093bd8f4e0SCharlie Barto case 0xdb3345: // 45 33 db : xor r11d, r11d 81057466db7Sbernhardu case 0xc08445: // 45 84 c0 : test r8b,r8b 81157466db7Sbernhardu case 0xd28445: // 45 84 d2 : test r10b,r10b 8123bd8f4e0SCharlie Barto case 0xdb8548: // 48 85 db : test rbx, rbx 8133bd8f4e0SCharlie Barto case 0xdb854d: // 4d 85 db : test r11, r11 8143bd8f4e0SCharlie Barto case 0xdc8b4c: // 4c 8b dc : mov r11, rsp 8153bd8f4e0SCharlie Barto case 0xe48548: // 48 85 e4 : test rsp, rsp 8163bd8f4e0SCharlie Barto case 0xe4854d: // 4d 85 e4 : test r12, r12 81757466db7Sbernhardu case 0xc88948: // 48 89 c8 : mov rax,rcx 81857466db7Sbernhardu case 0xcb8948: // 48 89 cb : mov rbx,rcx 81957466db7Sbernhardu case 0xd08948: // 48 89 d0 : mov rax,rdx 82057466db7Sbernhardu case 0xd18948: // 48 89 d1 : mov rcx,rdx 82157466db7Sbernhardu case 0xd38948: // 48 89 d3 : mov rbx,rdx 8223bd8f4e0SCharlie Barto case 0xe58948: // 48 89 e5 : mov rbp, rsp 8233bd8f4e0SCharlie Barto case 0xed8548: // 48 85 ed : test rbp, rbp 82457466db7Sbernhardu case 0xc88949: // 49 89 c8 : mov r8, rcx 82557466db7Sbernhardu case 0xc98949: // 49 89 c9 : mov r9, rcx 82657466db7Sbernhardu case 0xca8949: // 49 89 ca : mov r10,rcx 82757466db7Sbernhardu case 0xd08949: // 49 89 d0 : mov r8, rdx 82857466db7Sbernhardu case 0xd18949: // 49 89 d1 : mov r9, rdx 82957466db7Sbernhardu case 0xd28949: // 49 89 d2 : mov r10, rdx 83057466db7Sbernhardu case 0xd38949: // 49 89 d3 : mov r11, rdx 8313bd8f4e0SCharlie Barto case 0xed854d: // 4d 85 ed : test r13, r13 8323bd8f4e0SCharlie Barto case 0xf6854d: // 4d 85 f6 : test r14, r14 8333bd8f4e0SCharlie Barto case 0xff854d: // 4d 85 ff : test r15, r15 834ebbce04cSNico Weber return 3; 835ebbce04cSNico Weber 8363bd8f4e0SCharlie Barto case 0x245489: // 89 54 24 XX : mov DWORD PTR[rsp + XX], edx 8373bd8f4e0SCharlie Barto case 0x428d44: // 44 8d 42 XX : lea r8d , [rdx + XX] 8383bd8f4e0SCharlie Barto case 0x588948: // 48 89 58 XX : mov QWORD PTR[rax + XX], rbx 839ebbce04cSNico Weber case 0xec8348: // 48 83 ec XX : sub rsp, XX 840ebbce04cSNico Weber case 0xf88349: // 49 83 f8 XX : cmp r8, XX 84156592a81Sbernhardu case 0x488d49: // 49 8d 48 XX : lea rcx, [...] 84256592a81Sbernhardu case 0x048d4c: // 4c 8d 04 XX : lea r8, [...] 84356592a81Sbernhardu case 0x148d4e: // 4e 8d 14 XX : lea r10, [...] 84456592a81Sbernhardu case 0x398366: // 66 83 39 XX : cmp WORD PTR [rcx], XX 845ebbce04cSNico Weber return 4; 846ebbce04cSNico Weber 8475f405707Sbernhardu case 0x441F0F: // 0F 1F 44 XX XX : nop DWORD PTR [...] 8483bd8f4e0SCharlie Barto case 0x246483: // 83 64 24 XX YY : and DWORD PTR [rsp+XX], YY 8493bd8f4e0SCharlie Barto return 5; 8503bd8f4e0SCharlie Barto 8513bd8f4e0SCharlie Barto case 0x788166: // 66 81 78 XX YY YY cmp WORD PTR [rax+XX], YY YY 8523bd8f4e0SCharlie Barto case 0x798166: // 66 81 79 XX YY YY cmp WORD PTR [rcx+XX], YY YY 8533bd8f4e0SCharlie Barto case 0x7a8166: // 66 81 7a XX YY YY cmp WORD PTR [rdx+XX], YY YY 8543bd8f4e0SCharlie Barto case 0x7b8166: // 66 81 7b XX YY YY cmp WORD PTR [rbx+XX], YY YY 8553bd8f4e0SCharlie Barto case 0x7e8166: // 66 81 7e XX YY YY cmp WORD PTR [rsi+XX], YY YY 8563bd8f4e0SCharlie Barto case 0x7f8166: // 66 81 7f XX YY YY cmp WORD PTR [rdi+XX], YY YY 8573bd8f4e0SCharlie Barto return 6; 8583bd8f4e0SCharlie Barto 859ebbce04cSNico Weber case 0xec8148: // 48 81 EC XX XX XX XX : sub rsp, XXXXXXXX 860*bbf37706Sbernhardu case 0xc0c748: // 48 C7 C0 XX XX XX XX : mov rax, XX XX XX XX 861ebbce04cSNico Weber return 7; 862ebbce04cSNico Weber 8633bd8f4e0SCharlie Barto // clang-format off 8643bd8f4e0SCharlie Barto case 0x788141: // 41 81 78 XX YY YY YY YY : cmp DWORD PTR [r8+YY], XX XX XX XX 8653bd8f4e0SCharlie Barto case 0x798141: // 41 81 79 XX YY YY YY YY : cmp DWORD PTR [r9+YY], XX XX XX XX 8663bd8f4e0SCharlie Barto case 0x7a8141: // 41 81 7a XX YY YY YY YY : cmp DWORD PTR [r10+YY], XX XX XX XX 8673bd8f4e0SCharlie Barto case 0x7b8141: // 41 81 7b XX YY YY YY YY : cmp DWORD PTR [r11+YY], XX XX XX XX 8683bd8f4e0SCharlie Barto case 0x7d8141: // 41 81 7d XX YY YY YY YY : cmp DWORD PTR [r13+YY], XX XX XX XX 8693bd8f4e0SCharlie Barto case 0x7e8141: // 41 81 7e XX YY YY YY YY : cmp DWORD PTR [r14+YY], XX XX XX XX 8703bd8f4e0SCharlie Barto case 0x7f8141: // 41 81 7f YY XX XX XX XX : cmp DWORD PTR [r15+YY], XX XX XX XX 8713bd8f4e0SCharlie Barto case 0x247c81: // 81 7c 24 YY XX XX XX XX : cmp DWORD PTR [rsp+YY], XX XX XX XX 8723bd8f4e0SCharlie Barto return 8; 8733bd8f4e0SCharlie Barto // clang-format on 8743bd8f4e0SCharlie Barto 875ebbce04cSNico Weber case 0x058b48: // 48 8b 05 XX XX XX XX : 876ebbce04cSNico Weber // mov rax, QWORD PTR [rip + XXXXXXXX] 87742383242SCharlie Barto case 0x058d48: // 48 8d 05 XX XX XX XX : 87842383242SCharlie Barto // lea rax, QWORD PTR [rip + XXXXXXXX] 87955f5d68cSHans case 0x0d8948: // 48 89 0d XX XX XX XX : 88055f5d68cSHans // mov QWORD PTR [rip + XXXXXXXX], rcx 88155f5d68cSHans case 0x158948: // 48 89 15 XX XX XX XX : 88255f5d68cSHans // mov QWORD PTR [rip + XXXXXXXX], rdx 883ebbce04cSNico Weber case 0x25ff48: // 48 ff 25 XX XX XX XX : 884ebbce04cSNico Weber // rex.W jmp QWORD PTR [rip + XXXXXXXX] 885160e8eb4Snicole mazzuca case 0x158D4C: // 4c 8d 15 XX XX XX XX : lea r10, [rip + XX] 886ebbce04cSNico Weber // Instructions having offset relative to 'rip' need offset adjustment. 887ebbce04cSNico Weber if (rel_offset) 888ebbce04cSNico Weber *rel_offset = 3; 889ebbce04cSNico Weber return 7; 890ebbce04cSNico Weber 891ebbce04cSNico Weber case 0x2444c7: // C7 44 24 XX YY YY YY YY 892ebbce04cSNico Weber // mov dword ptr [rsp + XX], YYYYYYYY 893ebbce04cSNico Weber return 8; 894213c90d3Sbernhardu 895213c90d3Sbernhardu case 0x7c8141: // 41 81 7c ZZ YY XX XX XX XX 896213c90d3Sbernhardu // cmp DWORD PTR [reg+reg*n+YY], XX XX XX XX 897213c90d3Sbernhardu return 9; 898ebbce04cSNico Weber } 899ebbce04cSNico Weber 900ebbce04cSNico Weber switch (*(u32*)(address)) { 90156592a81Sbernhardu case 0x01b60f44: // 44 0f b6 01 : movzx r8d, BYTE PTR [rcx] 90256592a81Sbernhardu case 0x09b60f44: // 44 0f b6 09 : movzx r9d, BYTE PTR [rcx] 90356592a81Sbernhardu case 0x0ab60f44: // 44 0f b6 0a : movzx r8d, BYTE PTR [rdx] 90456592a81Sbernhardu case 0x11b60f44: // 44 0f b6 11 : movzx r10d, BYTE PTR [rcx] 905ce4618a9SMike Hommey case 0x1ab60f44: // 44 0f b6 1a : movzx r11d, BYTE PTR [rdx] 9068417f6afSHans Wennborg return 4; 907ebbce04cSNico Weber case 0x24448b48: // 48 8b 44 24 XX : mov rax, QWORD ptr [rsp + XX] 908ebbce04cSNico Weber case 0x246c8948: // 48 89 6C 24 XX : mov QWORD ptr [rsp + XX], rbp 909ebbce04cSNico Weber case 0x245c8948: // 48 89 5c 24 XX : mov QWORD PTR [rsp + XX], rbx 910ebbce04cSNico Weber case 0x24748948: // 48 89 74 24 XX : mov QWORD PTR [rsp + XX], rsi 9117cd109b9SAlexandre Ganea case 0x247c8948: // 48 89 7c 24 XX : mov QWORD PTR [rsp + XX], rdi 912ebbce04cSNico Weber case 0x244C8948: // 48 89 4C 24 XX : mov QWORD PTR [rsp + XX], rcx 913ebbce04cSNico Weber case 0x24548948: // 48 89 54 24 XX : mov QWORD PTR [rsp + XX], rdx 914ebbce04cSNico Weber case 0x244c894c: // 4c 89 4c 24 XX : mov QWORD PTR [rsp + XX], r9 915ebbce04cSNico Weber case 0x2444894c: // 4c 89 44 24 XX : mov QWORD PTR [rsp + XX], r8 9163bd8f4e0SCharlie Barto case 0x244c8944: // 44 89 4c 24 XX mov DWORD PTR [rsp + XX], r9d 9173bd8f4e0SCharlie Barto case 0x24448944: // 44 89 44 24 XX mov DWORD PTR [rsp + XX], r8d 9183bd8f4e0SCharlie Barto case 0x246c8d48: // 48 8d 6c 24 XX : lea rbp, [rsp + XX] 919ebbce04cSNico Weber return 5; 9203bd8f4e0SCharlie Barto case 0x24648348: // 48 83 64 24 XX YY : and QWORD PTR [rsp + XX], YY 921ebbce04cSNico Weber return 6; 922*bbf37706Sbernhardu case 0x24A48D48: // 48 8D A4 24 XX XX XX XX : lea rsp, [rsp + XX XX XX XX] 923*bbf37706Sbernhardu return 8; 924ebbce04cSNico Weber } 925ebbce04cSNico Weber 9265f405707Sbernhardu switch (0xFFFFFFFFFFULL & *(u64 *)(address)) { 9275f405707Sbernhardu case 0xC07E0F4866: // 66 48 0F 7E C0 : movq rax, xmm0 9285f405707Sbernhardu return 5; 9295f405707Sbernhardu } 9305f405707Sbernhardu 931ebbce04cSNico Weber #else 932ebbce04cSNico Weber 933ebbce04cSNico Weber switch (*(u8*)address) { 934ebbce04cSNico Weber case 0xA1: // A1 XX XX XX XX : mov eax, dword ptr ds:[XXXXXXXX] 935ebbce04cSNico Weber return 5; 936ebbce04cSNico Weber } 937ebbce04cSNico Weber switch (*(u16*)address) { 938ebbce04cSNico Weber case 0x458B: // 8B 45 XX : mov eax, dword ptr [ebp + XX] 939ebbce04cSNico Weber case 0x5D8B: // 8B 5D XX : mov ebx, dword ptr [ebp + XX] 940ebbce04cSNico Weber case 0x7D8B: // 8B 7D XX : mov edi, dword ptr [ebp + XX] 9413bd8f4e0SCharlie Barto case 0x758B: // 8B 75 XX : mov esi, dword ptr [ebp + XX] 942ebbce04cSNico Weber case 0x75FF: // FF 75 XX : push dword ptr [ebp + XX] 943ebbce04cSNico Weber return 3; 944ebbce04cSNico Weber case 0xC1F7: // F7 C1 XX YY ZZ WW : test ecx, WWZZYYXX 945ebbce04cSNico Weber return 6; 946ebbce04cSNico Weber case 0x3D83: // 83 3D XX YY ZZ WW TT : cmp TT, WWZZYYXX 947ebbce04cSNico Weber return 7; 948ebbce04cSNico Weber case 0x7D83: // 83 7D XX YY : cmp dword ptr [ebp + XX], YY 949ebbce04cSNico Weber return 4; 950ebbce04cSNico Weber } 951ebbce04cSNico Weber 952ebbce04cSNico Weber switch (0x00FFFFFF & *(u32*)address) { 953ebbce04cSNico Weber case 0x24448A: // 8A 44 24 XX : mov eal, dword ptr [esp + XX] 954ebbce04cSNico Weber case 0x24448B: // 8B 44 24 XX : mov eax, dword ptr [esp + XX] 955ebbce04cSNico Weber case 0x244C8B: // 8B 4C 24 XX : mov ecx, dword ptr [esp + XX] 956ebbce04cSNico Weber case 0x24548B: // 8B 54 24 XX : mov edx, dword ptr [esp + XX] 957ca40985eSAlvin Wong case 0x245C8B: // 8B 5C 24 XX : mov ebx, dword ptr [esp + XX] 958ca40985eSAlvin Wong case 0x246C8B: // 8B 6C 24 XX : mov ebp, dword ptr [esp + XX] 959ebbce04cSNico Weber case 0x24748B: // 8B 74 24 XX : mov esi, dword ptr [esp + XX] 960ebbce04cSNico Weber case 0x247C8B: // 8B 7C 24 XX : mov edi, dword ptr [esp + XX] 961ebbce04cSNico Weber return 4; 962ebbce04cSNico Weber } 963ebbce04cSNico Weber 964ebbce04cSNico Weber switch (*(u32*)address) { 965ebbce04cSNico Weber case 0x2444B60F: // 0F B6 44 24 XX : movzx eax, byte ptr [esp + XX] 966ebbce04cSNico Weber return 5; 967ebbce04cSNico Weber } 968ebbce04cSNico Weber #endif 969ebbce04cSNico Weber 9700716888dSAlvin Wong // Unknown instruction! This might happen when we add a new interceptor, use 9710716888dSAlvin Wong // a new compiler version, or if Windows changed how some functions are 9720716888dSAlvin Wong // compiled. In either case, we print the address and 8 bytes of instructions 9730716888dSAlvin Wong // to notify the user about the error and to help identify the unknown 9740716888dSAlvin Wong // instruction. Don't treat this as a fatal error, though we can break the 9750716888dSAlvin Wong // debugger if one has been attached. 9760716888dSAlvin Wong u8 *bytes = (u8 *)address; 9770716888dSAlvin Wong ReportError( 9780716888dSAlvin Wong "interception_win: unhandled instruction at %p: %02x %02x %02x %02x %02x " 9790716888dSAlvin Wong "%02x %02x %02x\n", 9800716888dSAlvin Wong (void *)address, bytes[0], bytes[1], bytes[2], bytes[3], bytes[4], 9810716888dSAlvin Wong bytes[5], bytes[6], bytes[7]); 9827b5571f3SAlvin Wong if (::IsDebuggerPresent()) 9837b5571f3SAlvin Wong __debugbreak(); 984ebbce04cSNico Weber return 0; 985ebbce04cSNico Weber } 986ebbce04cSNico Weber 98736b1811dSbernhardu size_t TestOnlyGetInstructionSize(uptr address, size_t *rel_offset) { 98836b1811dSbernhardu return GetInstructionSize(address, rel_offset); 98936b1811dSbernhardu } 99036b1811dSbernhardu 991ebbce04cSNico Weber // Returns 0 on error. 992ebbce04cSNico Weber static size_t RoundUpToInstrBoundary(size_t size, uptr address) { 993ebbce04cSNico Weber size_t cursor = 0; 994ebbce04cSNico Weber while (cursor < size) { 995ebbce04cSNico Weber size_t instruction_size = GetInstructionSize(address + cursor); 996ebbce04cSNico Weber if (!instruction_size) 997ebbce04cSNico Weber return 0; 998ebbce04cSNico Weber cursor += instruction_size; 999ebbce04cSNico Weber } 1000ebbce04cSNico Weber return cursor; 1001ebbce04cSNico Weber } 1002ebbce04cSNico Weber 1003ebbce04cSNico Weber static bool CopyInstructions(uptr to, uptr from, size_t size) { 1004ebbce04cSNico Weber size_t cursor = 0; 1005ebbce04cSNico Weber while (cursor != size) { 1006ebbce04cSNico Weber size_t rel_offset = 0; 1007ebbce04cSNico Weber size_t instruction_size = GetInstructionSize(from + cursor, &rel_offset); 10087b5571f3SAlvin Wong if (!instruction_size) 10097b5571f3SAlvin Wong return false; 101046fe36a4SAlex Richardson _memcpy((void *)(to + cursor), (void *)(from + cursor), 1011ebbce04cSNico Weber (size_t)instruction_size); 1012ebbce04cSNico Weber if (rel_offset) { 1013ebbce04cSNico Weber # if SANITIZER_WINDOWS64 1014bc34a833Snicole mazzuca // we want to make sure that the new relative offset still fits in 32-bits 1015bc34a833Snicole mazzuca // this will be untrue if relocated_offset \notin [-2**31, 2**31) 1016bc34a833Snicole mazzuca s64 delta = to - from; 1017bc34a833Snicole mazzuca s64 relocated_offset = *(s32 *)(to + cursor + rel_offset) - delta; 1018cdfd4cffSHans if (-0x8000'0000ll > relocated_offset || 1019cdfd4cffSHans relocated_offset > 0x7FFF'FFFFll) { 1020cdfd4cffSHans ReportError( 1021cdfd4cffSHans "interception_win: CopyInstructions relocated_offset %lld outside " 1022cdfd4cffSHans "32-bit range\n", 1023cdfd4cffSHans (long long)relocated_offset); 1024ebbce04cSNico Weber return false; 1025cdfd4cffSHans } 1026bc34a833Snicole mazzuca # else 1027bc34a833Snicole mazzuca // on 32-bit, the relative offset will always be correct 1028bc34a833Snicole mazzuca s32 delta = to - from; 1029bc34a833Snicole mazzuca s32 relocated_offset = *(s32 *)(to + cursor + rel_offset) - delta; 1030ebbce04cSNico Weber # endif 1031bc34a833Snicole mazzuca *(s32 *)(to + cursor + rel_offset) = relocated_offset; 1032ebbce04cSNico Weber } 1033ebbce04cSNico Weber cursor += instruction_size; 1034ebbce04cSNico Weber } 1035ebbce04cSNico Weber return true; 1036ebbce04cSNico Weber } 1037ebbce04cSNico Weber 1038ebbce04cSNico Weber 1039ebbce04cSNico Weber #if !SANITIZER_WINDOWS64 1040ebbce04cSNico Weber bool OverrideFunctionWithDetour( 1041ebbce04cSNico Weber uptr old_func, uptr new_func, uptr *orig_old_func) { 1042ebbce04cSNico Weber const int kDetourHeaderLen = 5; 1043ebbce04cSNico Weber const u16 kDetourInstruction = 0xFF8B; 1044ebbce04cSNico Weber 1045ebbce04cSNico Weber uptr header = (uptr)old_func - kDetourHeaderLen; 1046ebbce04cSNico Weber uptr patch_length = kDetourHeaderLen + kShortJumpInstructionLength; 1047ebbce04cSNico Weber 1048ebbce04cSNico Weber // Validate that the function is hookable. 1049ebbce04cSNico Weber if (*(u16*)old_func != kDetourInstruction || 1050ebbce04cSNico Weber !IsMemoryPadding(header, kDetourHeaderLen)) 1051ebbce04cSNico Weber return false; 1052ebbce04cSNico Weber 1053ebbce04cSNico Weber // Change memory protection to writable. 1054ebbce04cSNico Weber DWORD protection = 0; 1055ebbce04cSNico Weber if (!ChangeMemoryProtection(header, patch_length, &protection)) 1056ebbce04cSNico Weber return false; 1057ebbce04cSNico Weber 1058ebbce04cSNico Weber // Write a relative jump to the redirected function. 1059ebbce04cSNico Weber WriteJumpInstruction(header, new_func); 1060ebbce04cSNico Weber 1061ebbce04cSNico Weber // Write the short jump to the function prefix. 1062ebbce04cSNico Weber WriteShortJumpInstruction(old_func, header); 1063ebbce04cSNico Weber 1064ebbce04cSNico Weber // Restore previous memory protection. 1065ebbce04cSNico Weber if (!RestoreMemoryProtection(header, patch_length, protection)) 1066ebbce04cSNico Weber return false; 1067ebbce04cSNico Weber 1068ebbce04cSNico Weber if (orig_old_func) 1069ebbce04cSNico Weber *orig_old_func = old_func + kShortJumpInstructionLength; 1070ebbce04cSNico Weber 1071ebbce04cSNico Weber return true; 1072ebbce04cSNico Weber } 1073ebbce04cSNico Weber #endif 1074ebbce04cSNico Weber 1075ebbce04cSNico Weber bool OverrideFunctionWithRedirectJump( 1076ebbce04cSNico Weber uptr old_func, uptr new_func, uptr *orig_old_func) { 1077ebbce04cSNico Weber // Check whether the first instruction is a relative jump. 1078ebbce04cSNico Weber if (*(u8*)old_func != 0xE9) 1079ebbce04cSNico Weber return false; 1080ebbce04cSNico Weber 1081ebbce04cSNico Weber if (orig_old_func) { 108278c033b5SMarkus Böck sptr relative_offset = *(s32 *)(old_func + 1); 1083ebbce04cSNico Weber uptr absolute_target = old_func + relative_offset + kJumpInstructionLength; 1084ebbce04cSNico Weber *orig_old_func = absolute_target; 1085ebbce04cSNico Weber } 1086ebbce04cSNico Weber 1087ebbce04cSNico Weber #if SANITIZER_WINDOWS64 1088ebbce04cSNico Weber // If needed, get memory space for a trampoline jump. 1089ebbce04cSNico Weber uptr trampoline = AllocateMemoryForTrampoline(old_func, kDirectBranchLength); 1090ebbce04cSNico Weber if (!trampoline) 1091ebbce04cSNico Weber return false; 1092ebbce04cSNico Weber WriteDirectBranch(trampoline, new_func); 1093ebbce04cSNico Weber #endif 1094ebbce04cSNico Weber 1095ebbce04cSNico Weber // Change memory protection to writable. 1096ebbce04cSNico Weber DWORD protection = 0; 1097ebbce04cSNico Weber if (!ChangeMemoryProtection(old_func, kJumpInstructionLength, &protection)) 1098ebbce04cSNico Weber return false; 1099ebbce04cSNico Weber 1100ebbce04cSNico Weber // Write a relative jump to the redirected function. 1101ebbce04cSNico Weber WriteJumpInstruction(old_func, FIRST_32_SECOND_64(new_func, trampoline)); 1102ebbce04cSNico Weber 1103ebbce04cSNico Weber // Restore previous memory protection. 1104ebbce04cSNico Weber if (!RestoreMemoryProtection(old_func, kJumpInstructionLength, protection)) 1105ebbce04cSNico Weber return false; 1106ebbce04cSNico Weber 1107ebbce04cSNico Weber return true; 1108ebbce04cSNico Weber } 1109ebbce04cSNico Weber 1110ebbce04cSNico Weber bool OverrideFunctionWithHotPatch( 1111ebbce04cSNico Weber uptr old_func, uptr new_func, uptr *orig_old_func) { 1112ebbce04cSNico Weber const int kHotPatchHeaderLen = kBranchLength; 1113ebbce04cSNico Weber 1114ebbce04cSNico Weber uptr header = (uptr)old_func - kHotPatchHeaderLen; 1115ebbce04cSNico Weber uptr patch_length = kHotPatchHeaderLen + kShortJumpInstructionLength; 1116ebbce04cSNico Weber 1117ebbce04cSNico Weber // Validate that the function is hot patchable. 1118ebbce04cSNico Weber size_t instruction_size = GetInstructionSize(old_func); 1119ebbce04cSNico Weber if (instruction_size < kShortJumpInstructionLength || 1120ebbce04cSNico Weber !FunctionHasPadding(old_func, kHotPatchHeaderLen)) 1121ebbce04cSNico Weber return false; 1122ebbce04cSNico Weber 1123ebbce04cSNico Weber if (orig_old_func) { 1124ebbce04cSNico Weber // Put the needed instructions into the trampoline bytes. 1125ebbce04cSNico Weber uptr trampoline_length = instruction_size + kDirectBranchLength; 1126ebbce04cSNico Weber uptr trampoline = AllocateMemoryForTrampoline(old_func, trampoline_length); 1127ebbce04cSNico Weber if (!trampoline) 1128ebbce04cSNico Weber return false; 1129ebbce04cSNico Weber if (!CopyInstructions(trampoline, old_func, instruction_size)) 1130ebbce04cSNico Weber return false; 1131ebbce04cSNico Weber WriteDirectBranch(trampoline + instruction_size, 1132ebbce04cSNico Weber old_func + instruction_size); 1133ebbce04cSNico Weber *orig_old_func = trampoline; 1134ebbce04cSNico Weber } 1135ebbce04cSNico Weber 1136ebbce04cSNico Weber // If needed, get memory space for indirect address. 1137ebbce04cSNico Weber uptr indirect_address = 0; 1138ebbce04cSNico Weber #if SANITIZER_WINDOWS64 1139ebbce04cSNico Weber indirect_address = AllocateMemoryForTrampoline(old_func, kAddressLength); 1140ebbce04cSNico Weber if (!indirect_address) 1141ebbce04cSNico Weber return false; 1142ebbce04cSNico Weber #endif 1143ebbce04cSNico Weber 1144ebbce04cSNico Weber // Change memory protection to writable. 1145ebbce04cSNico Weber DWORD protection = 0; 1146ebbce04cSNico Weber if (!ChangeMemoryProtection(header, patch_length, &protection)) 1147ebbce04cSNico Weber return false; 1148ebbce04cSNico Weber 1149ebbce04cSNico Weber // Write jumps to the redirected function. 1150ebbce04cSNico Weber WriteBranch(header, indirect_address, new_func); 1151ebbce04cSNico Weber WriteShortJumpInstruction(old_func, header); 1152ebbce04cSNico Weber 1153ebbce04cSNico Weber // Restore previous memory protection. 1154ebbce04cSNico Weber if (!RestoreMemoryProtection(header, patch_length, protection)) 1155ebbce04cSNico Weber return false; 1156ebbce04cSNico Weber 1157ebbce04cSNico Weber return true; 1158ebbce04cSNico Weber } 1159ebbce04cSNico Weber 1160ebbce04cSNico Weber bool OverrideFunctionWithTrampoline( 1161ebbce04cSNico Weber uptr old_func, uptr new_func, uptr *orig_old_func) { 1162ebbce04cSNico Weber 1163ebbce04cSNico Weber size_t instructions_length = kBranchLength; 1164ebbce04cSNico Weber size_t padding_length = 0; 1165ebbce04cSNico Weber uptr indirect_address = 0; 1166ebbce04cSNico Weber 1167ebbce04cSNico Weber if (orig_old_func) { 1168ebbce04cSNico Weber // Find out the number of bytes of the instructions we need to copy 1169ebbce04cSNico Weber // to the trampoline. 1170ebbce04cSNico Weber instructions_length = RoundUpToInstrBoundary(kBranchLength, old_func); 1171ebbce04cSNico Weber if (!instructions_length) 1172ebbce04cSNico Weber return false; 1173ebbce04cSNico Weber 1174ebbce04cSNico Weber // Put the needed instructions into the trampoline bytes. 1175ebbce04cSNico Weber uptr trampoline_length = instructions_length + kDirectBranchLength; 1176ebbce04cSNico Weber uptr trampoline = AllocateMemoryForTrampoline(old_func, trampoline_length); 1177ebbce04cSNico Weber if (!trampoline) 1178ebbce04cSNico Weber return false; 1179ebbce04cSNico Weber if (!CopyInstructions(trampoline, old_func, instructions_length)) 1180ebbce04cSNico Weber return false; 1181ebbce04cSNico Weber WriteDirectBranch(trampoline + instructions_length, 1182ebbce04cSNico Weber old_func + instructions_length); 1183ebbce04cSNico Weber *orig_old_func = trampoline; 1184ebbce04cSNico Weber } 1185ebbce04cSNico Weber 1186ebbce04cSNico Weber #if SANITIZER_WINDOWS64 1187ebbce04cSNico Weber // Check if the targeted address can be encoded in the function padding. 1188ebbce04cSNico Weber // Otherwise, allocate it in the trampoline region. 1189ebbce04cSNico Weber if (IsMemoryPadding(old_func - kAddressLength, kAddressLength)) { 1190ebbce04cSNico Weber indirect_address = old_func - kAddressLength; 1191ebbce04cSNico Weber padding_length = kAddressLength; 1192ebbce04cSNico Weber } else { 1193ebbce04cSNico Weber indirect_address = AllocateMemoryForTrampoline(old_func, kAddressLength); 1194ebbce04cSNico Weber if (!indirect_address) 1195ebbce04cSNico Weber return false; 1196ebbce04cSNico Weber } 1197ebbce04cSNico Weber #endif 1198ebbce04cSNico Weber 1199ebbce04cSNico Weber // Change memory protection to writable. 1200ebbce04cSNico Weber uptr patch_address = old_func - padding_length; 1201ebbce04cSNico Weber uptr patch_length = instructions_length + padding_length; 1202ebbce04cSNico Weber DWORD protection = 0; 1203ebbce04cSNico Weber if (!ChangeMemoryProtection(patch_address, patch_length, &protection)) 1204ebbce04cSNico Weber return false; 1205ebbce04cSNico Weber 1206ebbce04cSNico Weber // Patch the original function. 1207ebbce04cSNico Weber WriteBranch(old_func, indirect_address, new_func); 1208ebbce04cSNico Weber 1209ebbce04cSNico Weber // Restore previous memory protection. 1210ebbce04cSNico Weber if (!RestoreMemoryProtection(patch_address, patch_length, protection)) 1211ebbce04cSNico Weber return false; 1212ebbce04cSNico Weber 1213ebbce04cSNico Weber return true; 1214ebbce04cSNico Weber } 1215ebbce04cSNico Weber 1216ebbce04cSNico Weber bool OverrideFunction( 1217ebbce04cSNico Weber uptr old_func, uptr new_func, uptr *orig_old_func) { 1218ebbce04cSNico Weber #if !SANITIZER_WINDOWS64 1219ebbce04cSNico Weber if (OverrideFunctionWithDetour(old_func, new_func, orig_old_func)) 1220ebbce04cSNico Weber return true; 1221ebbce04cSNico Weber #endif 1222ebbce04cSNico Weber if (OverrideFunctionWithRedirectJump(old_func, new_func, orig_old_func)) 1223ebbce04cSNico Weber return true; 1224ebbce04cSNico Weber if (OverrideFunctionWithHotPatch(old_func, new_func, orig_old_func)) 1225ebbce04cSNico Weber return true; 1226ebbce04cSNico Weber if (OverrideFunctionWithTrampoline(old_func, new_func, orig_old_func)) 1227ebbce04cSNico Weber return true; 1228ebbce04cSNico Weber return false; 1229ebbce04cSNico Weber } 1230ebbce04cSNico Weber 1231ebbce04cSNico Weber static void **InterestingDLLsAvailable() { 1232ebbce04cSNico Weber static const char *InterestingDLLs[] = { 1233ebbce04cSNico Weber "kernel32.dll", 123441b09bbeSCharlie Barto "msvcr100d.dll", // VS2010 123541b09bbeSCharlie Barto "msvcr110d.dll", // VS2012 123641b09bbeSCharlie Barto "msvcr120d.dll", // VS2013 123741b09bbeSCharlie Barto "vcruntime140d.dll", // VS2015 123841b09bbeSCharlie Barto "ucrtbased.dll", // Universal CRT 1239ebbce04cSNico Weber "msvcr100.dll", // VS2010 1240ebbce04cSNico Weber "msvcr110.dll", // VS2012 1241ebbce04cSNico Weber "msvcr120.dll", // VS2013 1242ebbce04cSNico Weber "vcruntime140.dll", // VS2015 1243ebbce04cSNico Weber "ucrtbase.dll", // Universal CRT 1244814a75dcSAlvin Wong # if (defined(__MINGW32__) && defined(__i386__)) 1245814a75dcSAlvin Wong "libc++.dll", // libc++ 1246814a75dcSAlvin Wong "libunwind.dll", // libunwind 1247814a75dcSAlvin Wong # endif 124869ebac7aSHans Wennborg // NTDLL must go last as it gets special treatment in OverrideFunction. 124941b09bbeSCharlie Barto "ntdll.dll", 125041b09bbeSCharlie Barto NULL 125141b09bbeSCharlie Barto }; 1252ebbce04cSNico Weber static void *result[ARRAY_SIZE(InterestingDLLs)] = { 0 }; 1253ebbce04cSNico Weber if (!result[0]) { 1254ebbce04cSNico Weber for (size_t i = 0, j = 0; InterestingDLLs[i]; ++i) { 1255ebbce04cSNico Weber if (HMODULE h = GetModuleHandleA(InterestingDLLs[i])) 1256ebbce04cSNico Weber result[j++] = (void *)h; 1257ebbce04cSNico Weber } 1258ebbce04cSNico Weber } 1259ebbce04cSNico Weber return &result[0]; 1260ebbce04cSNico Weber } 1261ebbce04cSNico Weber 1262ebbce04cSNico Weber namespace { 1263ebbce04cSNico Weber // Utility for reading loaded PE images. 1264ebbce04cSNico Weber template <typename T> class RVAPtr { 1265ebbce04cSNico Weber public: 1266ebbce04cSNico Weber RVAPtr(void *module, uptr rva) 1267ebbce04cSNico Weber : ptr_(reinterpret_cast<T *>(reinterpret_cast<char *>(module) + rva)) {} 1268ebbce04cSNico Weber operator T *() { return ptr_; } 1269ebbce04cSNico Weber T *operator->() { return ptr_; } 1270ebbce04cSNico Weber T *operator++() { return ++ptr_; } 1271ebbce04cSNico Weber 1272ebbce04cSNico Weber private: 1273ebbce04cSNico Weber T *ptr_; 1274ebbce04cSNico Weber }; 1275ebbce04cSNico Weber } // namespace 1276ebbce04cSNico Weber 1277ebbce04cSNico Weber // Internal implementation of GetProcAddress. At least since Windows 8, 1278ebbce04cSNico Weber // GetProcAddress appears to initialize DLLs before returning function pointers 1279ebbce04cSNico Weber // into them. This is problematic for the sanitizers, because they typically 1280ebbce04cSNico Weber // want to intercept malloc *before* MSVCRT initializes. Our internal 1281ebbce04cSNico Weber // implementation walks the export list manually without doing initialization. 1282ebbce04cSNico Weber uptr InternalGetProcAddress(void *module, const char *func_name) { 1283ebbce04cSNico Weber // Check that the module header is full and present. 1284ebbce04cSNico Weber RVAPtr<IMAGE_DOS_HEADER> dos_stub(module, 0); 1285ebbce04cSNico Weber RVAPtr<IMAGE_NT_HEADERS> headers(module, dos_stub->e_lfanew); 1286ebbce04cSNico Weber if (!module || dos_stub->e_magic != IMAGE_DOS_SIGNATURE || // "MZ" 1287ebbce04cSNico Weber headers->Signature != IMAGE_NT_SIGNATURE || // "PE\0\0" 1288ebbce04cSNico Weber headers->FileHeader.SizeOfOptionalHeader < 1289ebbce04cSNico Weber sizeof(IMAGE_OPTIONAL_HEADER)) { 1290ebbce04cSNico Weber return 0; 1291ebbce04cSNico Weber } 1292ebbce04cSNico Weber 1293ebbce04cSNico Weber IMAGE_DATA_DIRECTORY *export_directory = 1294ebbce04cSNico Weber &headers->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT]; 1295ebbce04cSNico Weber if (export_directory->Size == 0) 1296ebbce04cSNico Weber return 0; 1297ebbce04cSNico Weber RVAPtr<IMAGE_EXPORT_DIRECTORY> exports(module, 1298ebbce04cSNico Weber export_directory->VirtualAddress); 1299ebbce04cSNico Weber RVAPtr<DWORD> functions(module, exports->AddressOfFunctions); 1300ebbce04cSNico Weber RVAPtr<DWORD> names(module, exports->AddressOfNames); 1301ebbce04cSNico Weber RVAPtr<WORD> ordinals(module, exports->AddressOfNameOrdinals); 1302ebbce04cSNico Weber 1303ebbce04cSNico Weber for (DWORD i = 0; i < exports->NumberOfNames; i++) { 1304ebbce04cSNico Weber RVAPtr<char> name(module, names[i]); 130569ebac7aSHans Wennborg if (!_strcmp(func_name, name)) { 1306ebbce04cSNico Weber DWORD index = ordinals[i]; 1307ebbce04cSNico Weber RVAPtr<char> func(module, functions[index]); 1308ebbce04cSNico Weber 1309ebbce04cSNico Weber // Handle forwarded functions. 1310ebbce04cSNico Weber DWORD offset = functions[index]; 1311ebbce04cSNico Weber if (offset >= export_directory->VirtualAddress && 1312ebbce04cSNico Weber offset < export_directory->VirtualAddress + export_directory->Size) { 1313ebbce04cSNico Weber // An entry for a forwarded function is a string with the following 1314ebbce04cSNico Weber // format: "<module> . <function_name>" that is stored into the 1315ebbce04cSNico Weber // exported directory. 1316ebbce04cSNico Weber char function_name[256]; 131746fe36a4SAlex Richardson size_t funtion_name_length = _strlen(func); 1318cdfd4cffSHans if (funtion_name_length >= sizeof(function_name) - 1) { 1319055f1a77Sbernhardu ReportError("interception_win: func too long: '%s'\n", (char *)func); 1320ebbce04cSNico Weber InterceptionFailed(); 1321cdfd4cffSHans } 1322ebbce04cSNico Weber 132346fe36a4SAlex Richardson _memcpy(function_name, func, funtion_name_length); 1324ebbce04cSNico Weber function_name[funtion_name_length] = '\0'; 132546fe36a4SAlex Richardson char* separator = _strchr(function_name, '.'); 1326cdfd4cffSHans if (!separator) { 1327cdfd4cffSHans ReportError("interception_win: no separator in '%s'\n", 1328cdfd4cffSHans function_name); 1329ebbce04cSNico Weber InterceptionFailed(); 1330cdfd4cffSHans } 1331ebbce04cSNico Weber *separator = '\0'; 1332ebbce04cSNico Weber 1333ebbce04cSNico Weber void* redirected_module = GetModuleHandleA(function_name); 1334cdfd4cffSHans if (!redirected_module) { 1335cdfd4cffSHans ReportError("interception_win: GetModuleHandleA failed for '%s'\n", 1336cdfd4cffSHans function_name); 1337ebbce04cSNico Weber InterceptionFailed(); 1338cdfd4cffSHans } 1339ebbce04cSNico Weber return InternalGetProcAddress(redirected_module, separator + 1); 1340ebbce04cSNico Weber } 1341ebbce04cSNico Weber 1342ebbce04cSNico Weber return (uptr)(char *)func; 1343ebbce04cSNico Weber } 1344ebbce04cSNico Weber } 1345ebbce04cSNico Weber 1346ebbce04cSNico Weber return 0; 1347ebbce04cSNico Weber } 1348ebbce04cSNico Weber 1349ebbce04cSNico Weber bool OverrideFunction( 1350ebbce04cSNico Weber const char *func_name, uptr new_func, uptr *orig_old_func) { 135169ebac7aSHans Wennborg static const char *kNtDllIgnore[] = { 135269ebac7aSHans Wennborg "memcmp", "memcpy", "memmove", "memset" 135369ebac7aSHans Wennborg }; 135469ebac7aSHans Wennborg 1355ebbce04cSNico Weber bool hooked = false; 1356ebbce04cSNico Weber void **DLLs = InterestingDLLsAvailable(); 1357ebbce04cSNico Weber for (size_t i = 0; DLLs[i]; ++i) { 135869ebac7aSHans Wennborg if (DLLs[i + 1] == nullptr) { 135969ebac7aSHans Wennborg // This is the last DLL, i.e. NTDLL. It exports some functions that 136069ebac7aSHans Wennborg // we only want to override in the CRT. 136169ebac7aSHans Wennborg for (const char *ignored : kNtDllIgnore) { 136269ebac7aSHans Wennborg if (_strcmp(func_name, ignored) == 0) 136369ebac7aSHans Wennborg return hooked; 136469ebac7aSHans Wennborg } 136569ebac7aSHans Wennborg } 136669ebac7aSHans Wennborg 1367ebbce04cSNico Weber uptr func_addr = InternalGetProcAddress(DLLs[i], func_name); 1368ebbce04cSNico Weber if (func_addr && 1369ebbce04cSNico Weber OverrideFunction(func_addr, new_func, orig_old_func)) { 1370ebbce04cSNico Weber hooked = true; 1371ebbce04cSNico Weber } 1372ebbce04cSNico Weber } 1373ebbce04cSNico Weber return hooked; 1374ebbce04cSNico Weber } 1375ebbce04cSNico Weber 1376ebbce04cSNico Weber bool OverrideImportedFunction(const char *module_to_patch, 1377ebbce04cSNico Weber const char *imported_module, 1378ebbce04cSNico Weber const char *function_name, uptr new_function, 1379ebbce04cSNico Weber uptr *orig_old_func) { 1380ebbce04cSNico Weber HMODULE module = GetModuleHandleA(module_to_patch); 1381ebbce04cSNico Weber if (!module) 1382ebbce04cSNico Weber return false; 1383ebbce04cSNico Weber 1384ebbce04cSNico Weber // Check that the module header is full and present. 1385ebbce04cSNico Weber RVAPtr<IMAGE_DOS_HEADER> dos_stub(module, 0); 1386ebbce04cSNico Weber RVAPtr<IMAGE_NT_HEADERS> headers(module, dos_stub->e_lfanew); 1387ebbce04cSNico Weber if (!module || dos_stub->e_magic != IMAGE_DOS_SIGNATURE || // "MZ" 1388ebbce04cSNico Weber headers->Signature != IMAGE_NT_SIGNATURE || // "PE\0\0" 1389ebbce04cSNico Weber headers->FileHeader.SizeOfOptionalHeader < 1390ebbce04cSNico Weber sizeof(IMAGE_OPTIONAL_HEADER)) { 1391ebbce04cSNico Weber return false; 1392ebbce04cSNico Weber } 1393ebbce04cSNico Weber 1394ebbce04cSNico Weber IMAGE_DATA_DIRECTORY *import_directory = 1395ebbce04cSNico Weber &headers->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT]; 1396ebbce04cSNico Weber 1397ebbce04cSNico Weber // Iterate the list of imported DLLs. FirstThunk will be null for the last 1398ebbce04cSNico Weber // entry. 1399ebbce04cSNico Weber RVAPtr<IMAGE_IMPORT_DESCRIPTOR> imports(module, 1400ebbce04cSNico Weber import_directory->VirtualAddress); 1401ebbce04cSNico Weber for (; imports->FirstThunk != 0; ++imports) { 1402ebbce04cSNico Weber RVAPtr<const char> modname(module, imports->Name); 1403ebbce04cSNico Weber if (_stricmp(&*modname, imported_module) == 0) 1404ebbce04cSNico Weber break; 1405ebbce04cSNico Weber } 1406ebbce04cSNico Weber if (imports->FirstThunk == 0) 1407ebbce04cSNico Weber return false; 1408ebbce04cSNico Weber 1409ebbce04cSNico Weber // We have two parallel arrays: the import address table (IAT) and the table 1410ebbce04cSNico Weber // of names. They start out containing the same data, but the loader rewrites 1411ebbce04cSNico Weber // the IAT to hold imported addresses and leaves the name table in 1412ebbce04cSNico Weber // OriginalFirstThunk alone. 1413ebbce04cSNico Weber RVAPtr<IMAGE_THUNK_DATA> name_table(module, imports->OriginalFirstThunk); 1414ebbce04cSNico Weber RVAPtr<IMAGE_THUNK_DATA> iat(module, imports->FirstThunk); 1415ebbce04cSNico Weber for (; name_table->u1.Ordinal != 0; ++name_table, ++iat) { 1416ebbce04cSNico Weber if (!IMAGE_SNAP_BY_ORDINAL(name_table->u1.Ordinal)) { 1417ebbce04cSNico Weber RVAPtr<IMAGE_IMPORT_BY_NAME> import_by_name( 1418ebbce04cSNico Weber module, name_table->u1.ForwarderString); 1419ebbce04cSNico Weber const char *funcname = &import_by_name->Name[0]; 142069ebac7aSHans Wennborg if (_strcmp(funcname, function_name) == 0) 1421ebbce04cSNico Weber break; 1422ebbce04cSNico Weber } 1423ebbce04cSNico Weber } 1424ebbce04cSNico Weber if (name_table->u1.Ordinal == 0) 1425ebbce04cSNico Weber return false; 1426ebbce04cSNico Weber 1427ebbce04cSNico Weber // Now we have the correct IAT entry. Do the swap. We have to make the page 1428ebbce04cSNico Weber // read/write first. 1429ebbce04cSNico Weber if (orig_old_func) 1430ebbce04cSNico Weber *orig_old_func = iat->u1.AddressOfData; 1431ebbce04cSNico Weber DWORD old_prot, unused_prot; 1432ebbce04cSNico Weber if (!VirtualProtect(&iat->u1.AddressOfData, 4, PAGE_EXECUTE_READWRITE, 1433ebbce04cSNico Weber &old_prot)) 1434ebbce04cSNico Weber return false; 1435ebbce04cSNico Weber iat->u1.AddressOfData = new_function; 1436ebbce04cSNico Weber if (!VirtualProtect(&iat->u1.AddressOfData, 4, old_prot, &unused_prot)) 1437ebbce04cSNico Weber return false; // Not clear if this failure bothers us. 1438ebbce04cSNico Weber return true; 1439ebbce04cSNico Weber } 1440ebbce04cSNico Weber 1441ebbce04cSNico Weber } // namespace __interception 1442ebbce04cSNico Weber 144304ccbe6eSHans Wennborg #endif // SANITIZER_WINDOWS 1444