llvm-project/compiler-rt/lib/interception/interception_win.cc

520 lines
18 KiB
C++

//===-- interception_linux.cc -----------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file is a part of AddressSanitizer, an address sanity checker.
//
// Windows-specific interception methods.
//===----------------------------------------------------------------------===//
#ifdef _WIN32
#include "interception.h"
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
namespace __interception {
// FIXME: internal_str* and internal_mem* functions should be moved from the
// ASan sources into interception/.
static void _memset(void *p, int value, size_t sz) {
for (size_t i = 0; i < sz; ++i)
((char*)p)[i] = (char)value;
}
static void _memcpy(void *dst, void *src, size_t sz) {
char *dst_c = (char*)dst,
*src_c = (char*)src;
for (size_t i = 0; i < sz; ++i)
dst_c[i] = src_c[i];
}
#if SANITIZER_WINDOWS64
static void WriteIndirectJumpInstruction(char *jmp_from, uptr *indirect_target) { // NOLINT
// jmp [rip + XXYYZZWW] = FF 25 WW ZZ YY XX, where
// XXYYZZWW is an offset from jmp_from.
// The displacement is still 32-bit in x64, so indirect_target must be located
// within +/- 2GB range.
int offset = (int)(indirect_target - (uptr *)jmp_from);
jmp_from[0] = '\xFF';
jmp_from[1] = '\x25';
*(int*)(jmp_from + 2) = offset;
}
#else
static void WriteJumpInstruction(char *jmp_from, char *to) {
// jmp XXYYZZWW = E9 WW ZZ YY XX, where XXYYZZWW is an offset from jmp_from
// to the next instruction to the destination.
ptrdiff_t offset = to - jmp_from - 5;
*jmp_from = '\xE9';
*(ptrdiff_t*)(jmp_from + 1) = offset;
}
#endif
static void WriteTrampolineJumpInstruction(char *jmp_from, char *to) {
#if SANITIZER_WINDOWS64
// Emit an indirect jump through immediately following bytes:
// jmp_from:
// jmp [rip + 6]
// .quad to
// Store the address.
uptr *indirect_target = (uptr *)(jmp_from + 6);
*indirect_target = (uptr)to;
// Write the indirect jump.
WriteIndirectJumpInstruction(jmp_from, indirect_target);
#else
WriteJumpInstruction(jmp_from, to);
#endif
}
static void WriteInterceptorJumpInstruction(char *jmp_from, char *to) {
#if SANITIZER_WINDOWS64
// Emit an indirect jump through immediately following bytes:
// jmp_from:
// jmp [rip - 8]
// .quad to
// Store the address.
uptr *indirect_target = (uptr *)(jmp_from - 8);
*indirect_target = (uptr)to;
// Write the indirect jump.
WriteIndirectJumpInstruction(jmp_from, indirect_target);
#else
WriteJumpInstruction(jmp_from, to);
#endif
}
static char *GetMemoryForTrampoline(size_t size) {
// Trampolines are allocated from a common pool.
const int POOL_SIZE = 1024;
static char *pool = NULL;
static size_t pool_used = 0;
if (!pool) {
pool = (char *)VirtualAlloc(NULL, POOL_SIZE, MEM_RESERVE | MEM_COMMIT,
PAGE_EXECUTE_READWRITE);
// FIXME: Might want to apply PAGE_EXECUTE_READ access after all the
// interceptors are in place.
if (!pool)
return NULL;
_memset(pool, 0xCC /* int 3 */, POOL_SIZE);
}
if (pool_used + size > POOL_SIZE)
return NULL;
char *ret = pool + pool_used;
pool_used += size;
return ret;
}
// Returns 0 on error.
static size_t RoundUpToInstrBoundary(size_t size, char *code) {
#if SANITIZER_WINDOWS64
// Win64 RoundUpToInstrBoundary is a work in progress.
size_t cursor = 0;
while (cursor < size) {
switch (code[cursor]) {
case '\x57': // 57 : push rdi
cursor++;
continue;
case '\x90': // 90 : nop
cursor++;
continue;
case '\xb8': // b8 XX XX XX XX : mov eax, XX XX XX XX
cursor += 5;
continue;
}
switch (*(u16*)(code + cursor)) { // NOLINT
case 0x5540: // 40 55 : rex push rbp
case 0x5340: // 40 53 : rex push rbx
cursor += 2;
continue;
}
switch (0x00FFFFFF & *(u32*)(code + cursor)) {
case 0xc18b48: // 48 8b c1 : mov rax, rcx
case 0xc48b48: // 48 8b c4 : mov rax, rsp
case 0xd9f748: // 48 f7 d9 : neg rcx
case 0xd12b48: // 48 2b d1 : sub rdx, rcx
case 0x07c1f6: // f6 c1 07 : test cl, 0x7
case 0xc0854d: // 4d 85 c0 : test r8, r8
case 0xc2b60f: // 0f b6 c2 : movzx eax, dl
case 0xc03345: // 45 33 c0 : xor r8d, r8d
case 0xd98b4c: // 4c 8b d9 : mov r11, rcx
case 0xd28b4c: // 4c 8b d2 : mov r10, rdx
case 0xd2b60f: // 0f b6 d2 : movzx edx, dl
case 0xca2b48: // 48 2b ca : sub rcx, rdx
case 0x10b70f: // 0f b7 10 : movzx edx, WORD PTR [rax]
case 0xc00b4d: // 3d 0b c0 : or r8, r8
case 0xd18b48: // 48 8b d1 : mov rdx, rcx
case 0xdc8b4c: // 4c 8b dc : mov r11,rsp
case 0xd18b4c: // 4c 8b d1 : mov r10, rcx
cursor += 3;
continue;
case 0xec8348: // 48 83 ec XX : sub rsp, 0xXX
case 0xf88349: // 49 83 f8 XX : cmp r8, XX
case 0x588948: // 48 89 58 XX : mov QWORD PTR[rax + XX], rbx
cursor += 4;
continue;
case 0x058b48: // 48 8b 05 XX XX XX XX
// = mov rax, QWORD PTR [rip+ 0xXXXXXXXX]
case 0x25ff48: // 48 ff 25 XX XX XX XX
// = rex.W jmp QWORD PTR [rip + 0xXXXXXXXX]
cursor += 7;
continue;
}
switch (*(u32*)(code + cursor)) {
case 0x24448b48: // 48 8b 44 24 XX : mov rax, qword ptr [rsp + 0xXX]
cursor += 5;
continue;
}
// Check first 5 bytes.
switch (0xFFFFFFFFFFull & *(u64*)(code + cursor)) {
case 0x08245c8948: // 48 89 5c 24 08 : mov QWORD PTR [rsp+0x8], rbx
case 0x1024748948: // 48 89 74 24 10 : mov QWORD PTR [rsp+0x10], rsi
cursor += 5;
continue;
}
// Check 8 bytes.
switch (*(u64*)(code + cursor)) {
case 0x90909090909006EBull: // JMP +6, 6x NOP
cursor += 8;
continue;
}
// Unknown instructions!
__debugbreak();
}
return cursor;
#else
size_t cursor = 0;
while (cursor < size) {
switch (code[cursor]) {
case '\xE8': // E8 XX XX XX XX = call <func>
case '\xE9': // E9 XX XX XX XX = jmp <label>
case '\xC3': // C3 = ret
case '\xEB': // EB XX = jmp XX (short jump)
case '\x70': // 7X YY = jx XX (short conditional jump)
case '\x71':
case '\x72':
case '\x73':
case '\x74':
case '\x75':
case '\x76':
case '\x77':
case '\x78':
case '\x79':
case '\x7A':
case '\x7B':
case '\x7C':
case '\x7D':
case '\x7E':
case '\x7F':
return 0;
case '\x50': // push eax
case '\x51': // push ecx
case '\x52': // push edx
case '\x53': // push ebx
case '\x54': // push esp
case '\x55': // push ebp
case '\x56': // push esi
case '\x57': // push edi
case '\x5D': // pop ebp
cursor++;
continue;
case '\x6A': // 6A XX = push XX
cursor += 2;
continue;
case '\xB8': // B8 XX YY ZZ WW = mov eax, WWZZYYXX
cursor += 5;
continue;
}
switch (*(u16*)(code + cursor)) { // NOLINT
case 0xFF8B: // 8B FF = mov edi, edi
case 0xEC8B: // 8B EC = mov ebp, esp
case 0xC033: // 33 C0 = xor eax, eax
case 0xC933: // 33 C9 = xor ecx, ecx
cursor += 2;
continue;
case 0x458B: // 8B 45 XX = mov eax, dword ptr [ebp+XXh]
case 0x5D8B: // 8B 5D XX = mov ebx, dword ptr [ebp+XXh]
case 0x7D8B: // 8B 7D XX = mov edi, dword ptr [ebp+XXh]
case 0xEC83: // 83 EC XX = sub esp, XX
case 0x75FF: // FF 75 XX = push dword ptr [ebp+XXh]
cursor += 3;
continue;
case 0xC1F7: // F7 C1 XX YY ZZ WW = test ecx, WWZZYYXX
case 0x25FF: // FF 25 XX YY ZZ WW = jmp dword ptr ds:[WWZZYYXX]
cursor += 6;
continue;
case 0x3D83: // 83 3D XX YY ZZ WW TT = cmp TT, WWZZYYXX
cursor += 7;
continue;
case 0x7D83: // 83 7D XX YY = cmp dword ptr [ebp+XXh], YY
cursor += 4;
continue;
}
switch (0x00FFFFFF & *(u32*)(code + cursor)) {
case 0x24448A: // 8A 44 24 XX = mov eal, dword ptr [esp+XXh]
case 0x24448B: // 8B 44 24 XX = mov eax, dword ptr [esp+XXh]
case 0x244C8B: // 8B 4C 24 XX = mov ecx, dword ptr [esp+XXh]
case 0x24548B: // 8B 54 24 XX = mov edx, dword ptr [esp+XXh]
case 0x24748B: // 8B 74 24 XX = mov esi, dword ptr [esp+XXh]
case 0x247C8B: // 8B 7C 24 XX = mov edi, dword ptr [esp+XXh]
cursor += 4;
continue;
}
switch (*(u32*)(code + cursor)) {
case 0x2444B60F: // 0F B6 44 24 XX = movzx eax, byte ptr [esp+XXh]
cursor += 5;
continue;
}
// Unknown instruction!
// FIXME: Unknown instruction failures might happen when we add a new
// interceptor or a new compiler version. In either case, they should result
// in visible and readable error messages. However, merely calling abort()
// leads to an infinite recursion in CheckFailed.
// Do we have a good way to abort with an error message here?
__debugbreak();
return 0;
}
return cursor;
#endif
}
bool OverrideFunction(uptr old_func, uptr new_func, uptr *orig_old_func) {
// Function overriding works basically like this:
// On Win32, We write "jmp <new_func>" (5 bytes) at the beginning of
// the 'old_func' to override it.
// On Win64, We write "jmp [rip -8]" (6 bytes) at the beginning of
// the 'old_func' to override it, and use 8 bytes of data to store
// the full 64-bit address for new_func.
// We might want to be able to execute the original 'old_func' from the
// wrapper, in this case we need to keep the leading 5+ (6+ on Win64)
// bytes ('head') of the original code somewhere with a "jmp <old_func+head>".
// We call these 'head'+5/6 bytes of instructions a "trampoline".
char *old_bytes = (char *)old_func;
#if SANITIZER_WINDOWS64
size_t kHeadMin = 6; // The minimum size of the head to contain the 'jmp'.
size_t kTrampolineJumpSize = 14; // The total bytes used at the end of
// trampoline for jumping back to the
// remains of original function.
size_t kExtraPrevBytes = 8; // The extra bytes we need to mark READWRITE for
// page access, that is preceeding the begin
// of function.
#else
size_t kHeadMin = 5;
size_t kTrampolineJumpSize = 5;
size_t kExtraPrevBytes = 0;
#endif
size_t head = kHeadMin;
if (orig_old_func) {
// Find out the number of bytes of the instructions we need to copy
// to the trampoline and store it in 'head'.
head = RoundUpToInstrBoundary(kHeadMin, old_bytes);
if (!head)
return false;
// Put the needed instructions into the trampoline bytes.
char *trampoline = GetMemoryForTrampoline(head + kTrampolineJumpSize);
if (!trampoline)
return false;
_memcpy(trampoline, old_bytes, head);
WriteTrampolineJumpInstruction(trampoline + head, old_bytes + head);
*orig_old_func = (uptr)trampoline;
}
// Now put the "jmp <new_func>" instruction at the original code location.
// We should preserve the EXECUTE flag as some of our own code might be
// located in the same page (sic!). FIXME: might consider putting the
// __interception code into a separate section or something?
DWORD old_prot, unused_prot;
// TODO(wwchrome): Properly handle access violations when finding a safe
// region to store the indirect jump target address.
// Need to mark extra 8 bytes for Win64 because jmp [rip -8]
if (!VirtualProtect((void *)(old_bytes - kExtraPrevBytes),
head + kExtraPrevBytes, PAGE_EXECUTE_READWRITE,
&old_prot))
return false;
WriteInterceptorJumpInstruction(old_bytes, (char *)new_func);
_memset(old_bytes + kHeadMin, 0xCC /* int 3 */, head - kHeadMin);
// Restore the original permissions.
if (!VirtualProtect((void *)(old_bytes - kExtraPrevBytes),
head + kExtraPrevBytes, old_prot, &unused_prot))
return false; // not clear if this failure bothers us.
return true;
}
static void **InterestingDLLsAvailable() {
static const char *InterestingDLLs[] = {
"kernel32.dll",
"msvcr110.dll", // VS2012
"msvcr120.dll", // VS2013
"vcruntime140.dll", // VS2015
"ucrtbase.dll", // Universal CRT
// NTDLL should go last as it exports some functions that we should
// override in the CRT [presumably only used internally].
"ntdll.dll", NULL};
static void *result[ARRAY_SIZE(InterestingDLLs)] = { 0 };
if (!result[0]) {
for (size_t i = 0, j = 0; InterestingDLLs[i]; ++i) {
if (HMODULE h = GetModuleHandleA(InterestingDLLs[i]))
result[j++] = (void *)h;
}
}
return &result[0];
}
namespace {
// Utility for reading loaded PE images.
template <typename T> class RVAPtr {
public:
RVAPtr(void *module, uptr rva)
: ptr_(reinterpret_cast<T *>(reinterpret_cast<char *>(module) + rva)) {}
operator T *() { return ptr_; }
T *operator->() { return ptr_; }
T *operator++() { return ++ptr_; }
private:
T *ptr_;
};
} // namespace
// Internal implementation of GetProcAddress. At least since Windows 8,
// GetProcAddress appears to initialize DLLs before returning function pointers
// into them. This is problematic for the sanitizers, because they typically
// want to intercept malloc *before* MSVCRT initializes. Our internal
// implementation walks the export list manually without doing initialization.
uptr InternalGetProcAddress(void *module, const char *func_name) {
// Check that the module header is full and present.
RVAPtr<IMAGE_DOS_HEADER> dos_stub(module, 0);
RVAPtr<IMAGE_NT_HEADERS> headers(module, dos_stub->e_lfanew);
if (!module || dos_stub->e_magic != IMAGE_DOS_SIGNATURE || // "MZ"
headers->Signature != IMAGE_NT_SIGNATURE || // "PE\0\0"
headers->FileHeader.SizeOfOptionalHeader <
sizeof(IMAGE_OPTIONAL_HEADER)) {
return 0;
}
IMAGE_DATA_DIRECTORY *export_directory =
&headers->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT];
RVAPtr<IMAGE_EXPORT_DIRECTORY> exports(module,
export_directory->VirtualAddress);
RVAPtr<DWORD> functions(module, exports->AddressOfFunctions);
RVAPtr<DWORD> names(module, exports->AddressOfNames);
RVAPtr<WORD> ordinals(module, exports->AddressOfNameOrdinals);
for (DWORD i = 0; i < exports->NumberOfNames; i++) {
RVAPtr<char> name(module, names[i]);
if (!strcmp(func_name, name)) {
DWORD index = ordinals[i];
RVAPtr<char> func(module, functions[index]);
return (uptr)(char *)func;
}
}
return 0;
}
static bool GetFunctionAddressInDLLs(const char *func_name, uptr *func_addr) {
*func_addr = 0;
void **DLLs = InterestingDLLsAvailable();
for (size_t i = 0; *func_addr == 0 && DLLs[i]; ++i)
*func_addr = InternalGetProcAddress(DLLs[i], func_name);
return (*func_addr != 0);
}
bool OverrideFunction(const char *name, uptr new_func, uptr *orig_old_func) {
uptr orig_func;
if (!GetFunctionAddressInDLLs(name, &orig_func))
return false;
return OverrideFunction(orig_func, new_func, orig_old_func);
}
bool OverrideImportedFunction(const char *module_to_patch,
const char *imported_module,
const char *function_name, uptr new_function,
uptr *orig_old_func) {
HMODULE module = GetModuleHandleA(module_to_patch);
if (!module)
return false;
// Check that the module header is full and present.
RVAPtr<IMAGE_DOS_HEADER> dos_stub(module, 0);
RVAPtr<IMAGE_NT_HEADERS> headers(module, dos_stub->e_lfanew);
if (!module || dos_stub->e_magic != IMAGE_DOS_SIGNATURE || // "MZ"
headers->Signature != IMAGE_NT_SIGNATURE || // "PE\0\0"
headers->FileHeader.SizeOfOptionalHeader <
sizeof(IMAGE_OPTIONAL_HEADER)) {
return false;
}
IMAGE_DATA_DIRECTORY *import_directory =
&headers->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT];
// Iterate the list of imported DLLs. FirstThunk will be null for the last
// entry.
RVAPtr<IMAGE_IMPORT_DESCRIPTOR> imports(module,
import_directory->VirtualAddress);
for (; imports->FirstThunk != 0; ++imports) {
RVAPtr<const char> modname(module, imports->Name);
if (_stricmp(&*modname, imported_module) == 0)
break;
}
if (imports->FirstThunk == 0)
return false;
// We have two parallel arrays: the import address table (IAT) and the table
// of names. They start out containing the same data, but the loader rewrites
// the IAT to hold imported addresses and leaves the name table in
// OriginalFirstThunk alone.
RVAPtr<IMAGE_THUNK_DATA> name_table(module, imports->OriginalFirstThunk);
RVAPtr<IMAGE_THUNK_DATA> iat(module, imports->FirstThunk);
for (; name_table->u1.Ordinal != 0; ++name_table, ++iat) {
if (!IMAGE_SNAP_BY_ORDINAL(name_table->u1.Ordinal)) {
RVAPtr<IMAGE_IMPORT_BY_NAME> import_by_name(
module, name_table->u1.ForwarderString);
const char *funcname = &import_by_name->Name[0];
if (strcmp(funcname, function_name) == 0)
break;
}
}
if (name_table->u1.Ordinal == 0)
return false;
// Now we have the correct IAT entry. Do the swap. We have to make the page
// read/write first.
if (orig_old_func)
*orig_old_func = iat->u1.AddressOfData;
DWORD old_prot, unused_prot;
if (!VirtualProtect(&iat->u1.AddressOfData, 4, PAGE_EXECUTE_READWRITE,
&old_prot))
return false;
iat->u1.AddressOfData = new_function;
if (!VirtualProtect(&iat->u1.AddressOfData, 4, old_prot, &unused_prot))
return false; // Not clear if this failure bothers us.
return true;
}
} // namespace __interception
#endif // _WIN32