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28219f7f99
The following patch is result of libsanitizer/merge.sh from c425db2eb558c263 (yesterday evening). Bootstrapped/regtested on x86_64-linux and i686-linux (together with the follow-up 3 patches I'm about to post). BTW, seems upstream has added riscv64 support for I think lsan/tsan, so if anyone is willing to try it there, it would be a matter of copying e.g. the s390*-*-linux* libsanitizer/configure.tgt entry to riscv64-*-linux* with the obvious s/s390x/riscv64/ change in it.
1130 lines
38 KiB
C++
1130 lines
38 KiB
C++
//===-- interception_win.cpp ------------------------------------*- C++ -*-===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// This file is a part of AddressSanitizer, an address sanity checker.
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//
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// Windows-specific interception methods.
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//
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// This file is implementing several hooking techniques to intercept calls
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// to functions. The hooks are dynamically installed by modifying the assembly
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// code.
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//
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// The hooking techniques are making assumptions on the way the code is
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// generated and are safe under these assumptions.
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//
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// On 64-bit architecture, there is no direct 64-bit jump instruction. To allow
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// arbitrary branching on the whole memory space, the notion of trampoline
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// region is used. A trampoline region is a memory space withing 2G boundary
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// where it is safe to add custom assembly code to build 64-bit jumps.
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//
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// Hooking techniques
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// ==================
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//
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// 1) Detour
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//
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// The Detour hooking technique is assuming the presence of an header with
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// padding and an overridable 2-bytes nop instruction (mov edi, edi). The
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// nop instruction can safely be replaced by a 2-bytes jump without any need
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// to save the instruction. A jump to the target is encoded in the function
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// header and the nop instruction is replaced by a short jump to the header.
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//
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// head: 5 x nop head: jmp <hook>
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// func: mov edi, edi --> func: jmp short <head>
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// [...] real: [...]
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//
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// This technique is only implemented on 32-bit architecture.
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// Most of the time, Windows API are hookable with the detour technique.
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//
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// 2) Redirect Jump
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//
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// The redirect jump is applicable when the first instruction is a direct
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// jump. The instruction is replaced by jump to the hook.
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//
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// func: jmp <label> --> func: jmp <hook>
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//
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// On an 64-bit architecture, a trampoline is inserted.
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//
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// func: jmp <label> --> func: jmp <tramp>
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// [...]
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//
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// [trampoline]
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// tramp: jmp QWORD [addr]
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// addr: .bytes <hook>
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//
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// Note: <real> is equivalent to <label>.
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//
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// 3) HotPatch
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//
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// The HotPatch hooking is assuming the presence of an header with padding
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// and a first instruction with at least 2-bytes.
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//
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// The reason to enforce the 2-bytes limitation is to provide the minimal
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// space to encode a short jump. HotPatch technique is only rewriting one
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// instruction to avoid breaking a sequence of instructions containing a
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// branching target.
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//
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// Assumptions are enforced by MSVC compiler by using the /HOTPATCH flag.
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// see: https://msdn.microsoft.com/en-us/library/ms173507.aspx
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// Default padding length is 5 bytes in 32-bits and 6 bytes in 64-bits.
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//
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// head: 5 x nop head: jmp <hook>
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// func: <instr> --> func: jmp short <head>
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// [...] body: [...]
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//
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// [trampoline]
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// real: <instr>
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// jmp <body>
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//
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// On an 64-bit architecture:
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//
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// head: 6 x nop head: jmp QWORD [addr1]
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// func: <instr> --> func: jmp short <head>
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// [...] body: [...]
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//
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// [trampoline]
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// addr1: .bytes <hook>
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// real: <instr>
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// jmp QWORD [addr2]
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// addr2: .bytes <body>
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//
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// 4) Trampoline
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//
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// The Trampoline hooking technique is the most aggressive one. It is
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// assuming that there is a sequence of instructions that can be safely
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// replaced by a jump (enough room and no incoming branches).
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//
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// Unfortunately, these assumptions can't be safely presumed and code may
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// be broken after hooking.
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//
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// func: <instr> --> func: jmp <hook>
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// <instr>
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// [...] body: [...]
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//
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// [trampoline]
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// real: <instr>
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// <instr>
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// jmp <body>
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//
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// On an 64-bit architecture:
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//
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// func: <instr> --> func: jmp QWORD [addr1]
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// <instr>
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// [...] body: [...]
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//
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// [trampoline]
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// addr1: .bytes <hook>
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// real: <instr>
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// <instr>
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// jmp QWORD [addr2]
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// addr2: .bytes <body>
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//===----------------------------------------------------------------------===//
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#include "interception.h"
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#if SANITIZER_WINDOWS
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#include "sanitizer_common/sanitizer_platform.h"
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#define WIN32_LEAN_AND_MEAN
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#include <windows.h>
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namespace __interception {
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static const int kAddressLength = FIRST_32_SECOND_64(4, 8);
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static const int kJumpInstructionLength = 5;
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static const int kShortJumpInstructionLength = 2;
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UNUSED static const int kIndirectJumpInstructionLength = 6;
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static const int kBranchLength =
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FIRST_32_SECOND_64(kJumpInstructionLength, kIndirectJumpInstructionLength);
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static const int kDirectBranchLength = kBranchLength + kAddressLength;
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# if defined(_MSC_VER)
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# define INTERCEPTION_FORMAT(f, a)
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# else
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# define INTERCEPTION_FORMAT(f, a) __attribute__((format(printf, f, a)))
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# endif
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static void (*ErrorReportCallback)(const char *format, ...)
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INTERCEPTION_FORMAT(1, 2);
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void SetErrorReportCallback(void (*callback)(const char *format, ...)) {
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ErrorReportCallback = callback;
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}
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# define ReportError(...) \
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do { \
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if (ErrorReportCallback) \
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ErrorReportCallback(__VA_ARGS__); \
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} while (0)
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static void InterceptionFailed() {
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ReportError("interception_win: failed due to an unrecoverable error.\n");
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// This acts like an abort when no debugger is attached. According to an old
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// comment, calling abort() leads to an infinite recursion in CheckFailed.
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__debugbreak();
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}
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static bool DistanceIsWithin2Gig(uptr from, uptr target) {
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#if SANITIZER_WINDOWS64
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if (from < target)
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return target - from <= (uptr)0x7FFFFFFFU;
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else
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return from - target <= (uptr)0x80000000U;
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#else
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// In a 32-bit address space, the address calculation will wrap, so this check
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// is unnecessary.
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return true;
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#endif
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}
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static uptr GetMmapGranularity() {
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SYSTEM_INFO si;
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GetSystemInfo(&si);
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return si.dwAllocationGranularity;
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}
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UNUSED static uptr RoundUpTo(uptr size, uptr boundary) {
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return (size + boundary - 1) & ~(boundary - 1);
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}
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// FIXME: internal_str* and internal_mem* functions should be moved from the
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// ASan sources into interception/.
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static size_t _strlen(const char *str) {
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const char* p = str;
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while (*p != '\0') ++p;
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return p - str;
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}
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static char* _strchr(char* str, char c) {
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while (*str) {
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if (*str == c)
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return str;
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++str;
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}
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return nullptr;
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}
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static void _memset(void *p, int value, size_t sz) {
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for (size_t i = 0; i < sz; ++i)
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((char*)p)[i] = (char)value;
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}
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static void _memcpy(void *dst, void *src, size_t sz) {
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char *dst_c = (char*)dst,
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*src_c = (char*)src;
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for (size_t i = 0; i < sz; ++i)
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dst_c[i] = src_c[i];
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}
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static bool ChangeMemoryProtection(
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uptr address, uptr size, DWORD *old_protection) {
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return ::VirtualProtect((void*)address, size,
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PAGE_EXECUTE_READWRITE,
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old_protection) != FALSE;
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}
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static bool RestoreMemoryProtection(
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uptr address, uptr size, DWORD old_protection) {
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DWORD unused;
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return ::VirtualProtect((void*)address, size,
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old_protection,
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&unused) != FALSE;
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}
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static bool IsMemoryPadding(uptr address, uptr size) {
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u8* function = (u8*)address;
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for (size_t i = 0; i < size; ++i)
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if (function[i] != 0x90 && function[i] != 0xCC)
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return false;
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return true;
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}
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static const u8 kHintNop8Bytes[] = {
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0x0F, 0x1F, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00
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};
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template<class T>
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static bool FunctionHasPrefix(uptr address, const T &pattern) {
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u8* function = (u8*)address - sizeof(pattern);
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for (size_t i = 0; i < sizeof(pattern); ++i)
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if (function[i] != pattern[i])
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return false;
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return true;
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}
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static bool FunctionHasPadding(uptr address, uptr size) {
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if (IsMemoryPadding(address - size, size))
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return true;
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if (size <= sizeof(kHintNop8Bytes) &&
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FunctionHasPrefix(address, kHintNop8Bytes))
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return true;
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return false;
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}
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static void WritePadding(uptr from, uptr size) {
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_memset((void*)from, 0xCC, (size_t)size);
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}
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static void WriteJumpInstruction(uptr from, uptr target) {
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if (!DistanceIsWithin2Gig(from + kJumpInstructionLength, target)) {
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ReportError(
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"interception_win: cannot write jmp further than 2GB away, from %p to "
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"%p.\n",
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(void *)from, (void *)target);
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InterceptionFailed();
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}
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ptrdiff_t offset = target - from - kJumpInstructionLength;
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*(u8*)from = 0xE9;
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*(u32*)(from + 1) = offset;
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}
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static void WriteShortJumpInstruction(uptr from, uptr target) {
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sptr offset = target - from - kShortJumpInstructionLength;
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if (offset < -128 || offset > 127)
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InterceptionFailed();
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*(u8*)from = 0xEB;
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*(u8*)(from + 1) = (u8)offset;
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}
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#if SANITIZER_WINDOWS64
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static void WriteIndirectJumpInstruction(uptr from, uptr indirect_target) {
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// jmp [rip + <offset>] = FF 25 <offset> where <offset> is a relative
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// offset.
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// The offset is the distance from then end of the jump instruction to the
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// memory location containing the targeted address. The displacement is still
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// 32-bit in x64, so indirect_target must be located within +/- 2GB range.
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int offset = indirect_target - from - kIndirectJumpInstructionLength;
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if (!DistanceIsWithin2Gig(from + kIndirectJumpInstructionLength,
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indirect_target)) {
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ReportError(
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"interception_win: cannot write indirect jmp with target further than "
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"2GB away, from %p to %p.\n",
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(void *)from, (void *)indirect_target);
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InterceptionFailed();
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}
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*(u16*)from = 0x25FF;
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*(u32*)(from + 2) = offset;
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}
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#endif
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static void WriteBranch(
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uptr from, uptr indirect_target, uptr target) {
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#if SANITIZER_WINDOWS64
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WriteIndirectJumpInstruction(from, indirect_target);
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*(u64*)indirect_target = target;
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#else
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(void)indirect_target;
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WriteJumpInstruction(from, target);
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#endif
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}
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static void WriteDirectBranch(uptr from, uptr target) {
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#if SANITIZER_WINDOWS64
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// Emit an indirect jump through immediately following bytes:
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// jmp [rip + kBranchLength]
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// .quad <target>
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WriteBranch(from, from + kBranchLength, target);
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#else
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WriteJumpInstruction(from, target);
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#endif
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}
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struct TrampolineMemoryRegion {
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uptr content;
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uptr allocated_size;
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uptr max_size;
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};
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UNUSED static const uptr kTrampolineScanLimitRange = 1 << 31; // 2 gig
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static const int kMaxTrampolineRegion = 1024;
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static TrampolineMemoryRegion TrampolineRegions[kMaxTrampolineRegion];
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static void *AllocateTrampolineRegion(uptr image_address, size_t granularity) {
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#if SANITIZER_WINDOWS64
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uptr address = image_address;
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uptr scanned = 0;
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while (scanned < kTrampolineScanLimitRange) {
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MEMORY_BASIC_INFORMATION info;
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if (!::VirtualQuery((void*)address, &info, sizeof(info)))
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return nullptr;
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// Check whether a region can be allocated at |address|.
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if (info.State == MEM_FREE && info.RegionSize >= granularity) {
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void *page = ::VirtualAlloc((void*)RoundUpTo(address, granularity),
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granularity,
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MEM_RESERVE | MEM_COMMIT,
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PAGE_EXECUTE_READWRITE);
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return page;
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}
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// Move to the next region.
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address = (uptr)info.BaseAddress + info.RegionSize;
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scanned += info.RegionSize;
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}
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return nullptr;
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#else
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return ::VirtualAlloc(nullptr,
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granularity,
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MEM_RESERVE | MEM_COMMIT,
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PAGE_EXECUTE_READWRITE);
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#endif
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}
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// Used by unittests to release mapped memory space.
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void TestOnlyReleaseTrampolineRegions() {
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for (size_t bucket = 0; bucket < kMaxTrampolineRegion; ++bucket) {
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TrampolineMemoryRegion *current = &TrampolineRegions[bucket];
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if (current->content == 0)
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return;
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::VirtualFree((void*)current->content, 0, MEM_RELEASE);
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current->content = 0;
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}
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}
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static uptr AllocateMemoryForTrampoline(uptr image_address, size_t size) {
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// Find a region within 2G with enough space to allocate |size| bytes.
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TrampolineMemoryRegion *region = nullptr;
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for (size_t bucket = 0; bucket < kMaxTrampolineRegion; ++bucket) {
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TrampolineMemoryRegion* current = &TrampolineRegions[bucket];
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if (current->content == 0) {
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// No valid region found, allocate a new region.
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size_t bucket_size = GetMmapGranularity();
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void *content = AllocateTrampolineRegion(image_address, bucket_size);
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if (content == nullptr)
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return 0U;
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current->content = (uptr)content;
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current->allocated_size = 0;
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current->max_size = bucket_size;
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region = current;
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break;
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} else if (current->max_size - current->allocated_size > size) {
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#if SANITIZER_WINDOWS64
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// In 64-bits, the memory space must be allocated within 2G boundary.
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uptr next_address = current->content + current->allocated_size;
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if (next_address < image_address ||
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next_address - image_address >= 0x7FFF0000)
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continue;
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#endif
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// The space can be allocated in the current region.
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region = current;
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break;
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}
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}
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// Failed to find a region.
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if (region == nullptr)
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return 0U;
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// Allocate the space in the current region.
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uptr allocated_space = region->content + region->allocated_size;
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region->allocated_size += size;
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WritePadding(allocated_space, size);
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return allocated_space;
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}
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// The following prologues cannot be patched because of the short jump
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// jumping to the patching region.
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#if SANITIZER_WINDOWS64
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// ntdll!wcslen in Win11
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// 488bc1 mov rax,rcx
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// 0fb710 movzx edx,word ptr [rax]
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// 4883c002 add rax,2
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// 6685d2 test dx,dx
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// 75f4 jne -12
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static const u8 kPrologueWithShortJump1[] = {
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0x48, 0x8b, 0xc1, 0x0f, 0xb7, 0x10, 0x48, 0x83,
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0xc0, 0x02, 0x66, 0x85, 0xd2, 0x75, 0xf4,
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};
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// ntdll!strrchr in Win11
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// 4c8bc1 mov r8,rcx
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// 8a01 mov al,byte ptr [rcx]
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// 48ffc1 inc rcx
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// 84c0 test al,al
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// 75f7 jne -9
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static const u8 kPrologueWithShortJump2[] = {
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0x4c, 0x8b, 0xc1, 0x8a, 0x01, 0x48, 0xff, 0xc1,
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0x84, 0xc0, 0x75, 0xf7,
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};
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#endif
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// Returns 0 on error.
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static size_t GetInstructionSize(uptr address, size_t* rel_offset = nullptr) {
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#if SANITIZER_ARM64
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// An ARM64 instruction is 4 bytes long.
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return 4;
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#endif
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#if SANITIZER_WINDOWS64
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if (memcmp((u8*)address, kPrologueWithShortJump1,
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sizeof(kPrologueWithShortJump1)) == 0 ||
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memcmp((u8*)address, kPrologueWithShortJump2,
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sizeof(kPrologueWithShortJump2)) == 0) {
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return 0;
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}
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#endif
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switch (*(u64*)address) {
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case 0x90909090909006EB: // stub: jmp over 6 x nop.
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return 8;
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}
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switch (*(u8*)address) {
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case 0x90: // 90 : nop
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return 1;
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case 0x50: // push eax / rax
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case 0x51: // push ecx / rcx
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case 0x52: // push edx / rdx
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case 0x53: // push ebx / rbx
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case 0x54: // push esp / rsp
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case 0x55: // push ebp / rbp
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case 0x56: // push esi / rsi
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case 0x57: // push edi / rdi
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case 0x5D: // pop ebp / rbp
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return 1;
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|
case 0x6A: // 6A XX = push XX
|
|
return 2;
|
|
|
|
case 0xb8: // b8 XX XX XX XX : mov eax, XX XX XX XX
|
|
case 0xB9: // b9 XX XX XX XX : mov ecx, XX XX XX XX
|
|
return 5;
|
|
|
|
// Cannot overwrite control-instruction. Return 0 to indicate failure.
|
|
case 0xE9: // E9 XX XX XX XX : jmp <label>
|
|
case 0xE8: // E8 XX XX XX XX : call <func>
|
|
case 0xC3: // C3 : ret
|
|
case 0xEB: // EB XX : jmp XX (short jump)
|
|
case 0x70: // 7Y YY : jy XX (short conditional jump)
|
|
case 0x71:
|
|
case 0x72:
|
|
case 0x73:
|
|
case 0x74:
|
|
case 0x75:
|
|
case 0x76:
|
|
case 0x77:
|
|
case 0x78:
|
|
case 0x79:
|
|
case 0x7A:
|
|
case 0x7B:
|
|
case 0x7C:
|
|
case 0x7D:
|
|
case 0x7E:
|
|
case 0x7F:
|
|
return 0;
|
|
}
|
|
|
|
switch (*(u16*)(address)) {
|
|
case 0x018A: // 8A 01 : mov al, byte ptr [ecx]
|
|
case 0xFF8B: // 8B FF : mov edi, edi
|
|
case 0xEC8B: // 8B EC : mov ebp, esp
|
|
case 0xc889: // 89 C8 : mov eax, ecx
|
|
case 0xE589: // 89 E5 : mov ebp, esp
|
|
case 0xC18B: // 8B C1 : mov eax, ecx
|
|
case 0xC033: // 33 C0 : xor eax, eax
|
|
case 0xC933: // 33 C9 : xor ecx, ecx
|
|
case 0xD233: // 33 D2 : xor edx, edx
|
|
return 2;
|
|
|
|
// Cannot overwrite control-instruction. Return 0 to indicate failure.
|
|
case 0x25FF: // FF 25 XX XX XX XX : jmp [XXXXXXXX]
|
|
return 0;
|
|
}
|
|
|
|
switch (0x00FFFFFF & *(u32*)address) {
|
|
case 0x24A48D: // 8D A4 24 XX XX XX XX : lea esp, [esp + XX XX XX XX]
|
|
return 7;
|
|
}
|
|
|
|
#if SANITIZER_WINDOWS64
|
|
switch (*(u8*)address) {
|
|
case 0xA1: // A1 XX XX XX XX XX XX XX XX :
|
|
// movabs eax, dword ptr ds:[XXXXXXXX]
|
|
return 9;
|
|
|
|
case 0x83:
|
|
const u8 next_byte = *(u8*)(address + 1);
|
|
const u8 mod = next_byte >> 6;
|
|
const u8 rm = next_byte & 7;
|
|
if (mod == 1 && rm == 4)
|
|
return 5; // 83 ModR/M SIB Disp8 Imm8
|
|
// add|or|adc|sbb|and|sub|xor|cmp [r+disp8], imm8
|
|
}
|
|
|
|
switch (*(u16*)address) {
|
|
case 0x5040: // push rax
|
|
case 0x5140: // push rcx
|
|
case 0x5240: // push rdx
|
|
case 0x5340: // push rbx
|
|
case 0x5440: // push rsp
|
|
case 0x5540: // push rbp
|
|
case 0x5640: // push rsi
|
|
case 0x5740: // push rdi
|
|
case 0x5441: // push r12
|
|
case 0x5541: // push r13
|
|
case 0x5641: // push r14
|
|
case 0x5741: // push r15
|
|
case 0x9066: // Two-byte NOP
|
|
case 0xc084: // test al, al
|
|
case 0x018a: // mov al, byte ptr [rcx]
|
|
return 2;
|
|
|
|
case 0x058B: // 8B 05 XX XX XX XX : mov eax, dword ptr [XX XX XX XX]
|
|
if (rel_offset)
|
|
*rel_offset = 2;
|
|
return 6;
|
|
}
|
|
|
|
switch (0x00FFFFFF & *(u32*)address) {
|
|
case 0xe58948: // 48 8b c4 : mov rbp, rsp
|
|
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 0xc98548: // 48 85 C9 : test rcx, rcx
|
|
case 0xd28548: // 48 85 d2 : test rdx, rdx
|
|
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 0xc93345: // 45 33 c9 : xor r9d, r9d
|
|
case 0xdb3345: // 45 33 DB : xor r11d, r11d
|
|
case 0xd98b4c: // 4c 8b d9 : mov r11, rcx
|
|
case 0xd28b4c: // 4c 8b d2 : mov r10, rdx
|
|
case 0xc98b4c: // 4C 8B C9 : mov r9, rcx
|
|
case 0xc18b4c: // 4C 8B C1 : mov r8, rcx
|
|
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 0xc08b41: // 41 8b c0 : mov eax, r8d
|
|
case 0xd18b48: // 48 8b d1 : mov rdx, rcx
|
|
case 0xdc8b4c: // 4c 8b dc : mov r11, rsp
|
|
case 0xd18b4c: // 4c 8b d1 : mov r10, rcx
|
|
case 0xE0E483: // 83 E4 E0 : and esp, 0xFFFFFFE0
|
|
return 3;
|
|
|
|
case 0xec8348: // 48 83 ec XX : sub rsp, XX
|
|
case 0xf88349: // 49 83 f8 XX : cmp r8, XX
|
|
case 0x588948: // 48 89 58 XX : mov QWORD PTR[rax + XX], rbx
|
|
return 4;
|
|
|
|
case 0xec8148: // 48 81 EC XX XX XX XX : sub rsp, XXXXXXXX
|
|
return 7;
|
|
|
|
case 0x058b48: // 48 8b 05 XX XX XX XX :
|
|
// mov rax, QWORD PTR [rip + XXXXXXXX]
|
|
case 0x25ff48: // 48 ff 25 XX XX XX XX :
|
|
// rex.W jmp QWORD PTR [rip + XXXXXXXX]
|
|
case 0x158D4C: // 4c 8d 15 XX XX XX XX : lea r10, [rip + XX]
|
|
// Instructions having offset relative to 'rip' need offset adjustment.
|
|
if (rel_offset)
|
|
*rel_offset = 3;
|
|
return 7;
|
|
|
|
case 0x2444c7: // C7 44 24 XX YY YY YY YY
|
|
// mov dword ptr [rsp + XX], YYYYYYYY
|
|
return 8;
|
|
}
|
|
|
|
switch (*(u32*)(address)) {
|
|
case 0x24448b48: // 48 8b 44 24 XX : mov rax, QWORD ptr [rsp + XX]
|
|
case 0x246c8948: // 48 89 6C 24 XX : mov QWORD ptr [rsp + XX], rbp
|
|
case 0x245c8948: // 48 89 5c 24 XX : mov QWORD PTR [rsp + XX], rbx
|
|
case 0x24748948: // 48 89 74 24 XX : mov QWORD PTR [rsp + XX], rsi
|
|
case 0x247c8948: // 48 89 7c 24 XX : mov QWORD PTR [rsp + XX], rdi
|
|
case 0x244C8948: // 48 89 4C 24 XX : mov QWORD PTR [rsp + XX], rcx
|
|
case 0x24548948: // 48 89 54 24 XX : mov QWORD PTR [rsp + XX], rdx
|
|
case 0x244c894c: // 4c 89 4c 24 XX : mov QWORD PTR [rsp + XX], r9
|
|
case 0x2444894c: // 4c 89 44 24 XX : mov QWORD PTR [rsp + XX], r8
|
|
return 5;
|
|
case 0x24648348: // 48 83 64 24 XX : and QWORD PTR [rsp + XX], YY
|
|
return 6;
|
|
}
|
|
|
|
#else
|
|
|
|
switch (*(u8*)address) {
|
|
case 0xA1: // A1 XX XX XX XX : mov eax, dword ptr ds:[XXXXXXXX]
|
|
return 5;
|
|
}
|
|
switch (*(u16*)address) {
|
|
case 0x458B: // 8B 45 XX : mov eax, dword ptr [ebp + XX]
|
|
case 0x5D8B: // 8B 5D XX : mov ebx, dword ptr [ebp + XX]
|
|
case 0x7D8B: // 8B 7D XX : mov edi, dword ptr [ebp + XX]
|
|
case 0xEC83: // 83 EC XX : sub esp, XX
|
|
case 0x75FF: // FF 75 XX : push dword ptr [ebp + XX]
|
|
return 3;
|
|
case 0xC1F7: // F7 C1 XX YY ZZ WW : test ecx, WWZZYYXX
|
|
case 0x25FF: // FF 25 XX YY ZZ WW : jmp dword ptr ds:[WWZZYYXX]
|
|
return 6;
|
|
case 0x3D83: // 83 3D XX YY ZZ WW TT : cmp TT, WWZZYYXX
|
|
return 7;
|
|
case 0x7D83: // 83 7D XX YY : cmp dword ptr [ebp + XX], YY
|
|
return 4;
|
|
}
|
|
|
|
switch (0x00FFFFFF & *(u32*)address) {
|
|
case 0x24448A: // 8A 44 24 XX : mov eal, dword ptr [esp + XX]
|
|
case 0x24448B: // 8B 44 24 XX : mov eax, dword ptr [esp + XX]
|
|
case 0x244C8B: // 8B 4C 24 XX : mov ecx, dword ptr [esp + XX]
|
|
case 0x24548B: // 8B 54 24 XX : mov edx, dword ptr [esp + XX]
|
|
case 0x245C8B: // 8B 5C 24 XX : mov ebx, dword ptr [esp + XX]
|
|
case 0x246C8B: // 8B 6C 24 XX : mov ebp, dword ptr [esp + XX]
|
|
case 0x24748B: // 8B 74 24 XX : mov esi, dword ptr [esp + XX]
|
|
case 0x247C8B: // 8B 7C 24 XX : mov edi, dword ptr [esp + XX]
|
|
return 4;
|
|
}
|
|
|
|
switch (*(u32*)address) {
|
|
case 0x2444B60F: // 0F B6 44 24 XX : movzx eax, byte ptr [esp + XX]
|
|
return 5;
|
|
}
|
|
#endif
|
|
|
|
// Unknown instruction! This might happen when we add a new interceptor, use
|
|
// a new compiler version, or if Windows changed how some functions are
|
|
// compiled. In either case, we print the address and 8 bytes of instructions
|
|
// to notify the user about the error and to help identify the unknown
|
|
// instruction. Don't treat this as a fatal error, though we can break the
|
|
// debugger if one has been attached.
|
|
u8 *bytes = (u8 *)address;
|
|
ReportError(
|
|
"interception_win: unhandled instruction at %p: %02x %02x %02x %02x %02x "
|
|
"%02x %02x %02x\n",
|
|
(void *)address, bytes[0], bytes[1], bytes[2], bytes[3], bytes[4],
|
|
bytes[5], bytes[6], bytes[7]);
|
|
if (::IsDebuggerPresent())
|
|
__debugbreak();
|
|
return 0;
|
|
}
|
|
|
|
// Returns 0 on error.
|
|
static size_t RoundUpToInstrBoundary(size_t size, uptr address) {
|
|
size_t cursor = 0;
|
|
while (cursor < size) {
|
|
size_t instruction_size = GetInstructionSize(address + cursor);
|
|
if (!instruction_size)
|
|
return 0;
|
|
cursor += instruction_size;
|
|
}
|
|
return cursor;
|
|
}
|
|
|
|
static bool CopyInstructions(uptr to, uptr from, size_t size) {
|
|
size_t cursor = 0;
|
|
while (cursor != size) {
|
|
size_t rel_offset = 0;
|
|
size_t instruction_size = GetInstructionSize(from + cursor, &rel_offset);
|
|
if (!instruction_size)
|
|
return false;
|
|
_memcpy((void *)(to + cursor), (void *)(from + cursor),
|
|
(size_t)instruction_size);
|
|
if (rel_offset) {
|
|
# if SANITIZER_WINDOWS64
|
|
// we want to make sure that the new relative offset still fits in 32-bits
|
|
// this will be untrue if relocated_offset \notin [-2**31, 2**31)
|
|
s64 delta = to - from;
|
|
s64 relocated_offset = *(s32 *)(to + cursor + rel_offset) - delta;
|
|
if (-0x8000'0000ll > relocated_offset || relocated_offset > 0x7FFF'FFFFll)
|
|
return false;
|
|
# else
|
|
// on 32-bit, the relative offset will always be correct
|
|
s32 delta = to - from;
|
|
s32 relocated_offset = *(s32 *)(to + cursor + rel_offset) - delta;
|
|
# endif
|
|
*(s32 *)(to + cursor + rel_offset) = relocated_offset;
|
|
}
|
|
cursor += instruction_size;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
#if !SANITIZER_WINDOWS64
|
|
bool OverrideFunctionWithDetour(
|
|
uptr old_func, uptr new_func, uptr *orig_old_func) {
|
|
const int kDetourHeaderLen = 5;
|
|
const u16 kDetourInstruction = 0xFF8B;
|
|
|
|
uptr header = (uptr)old_func - kDetourHeaderLen;
|
|
uptr patch_length = kDetourHeaderLen + kShortJumpInstructionLength;
|
|
|
|
// Validate that the function is hookable.
|
|
if (*(u16*)old_func != kDetourInstruction ||
|
|
!IsMemoryPadding(header, kDetourHeaderLen))
|
|
return false;
|
|
|
|
// Change memory protection to writable.
|
|
DWORD protection = 0;
|
|
if (!ChangeMemoryProtection(header, patch_length, &protection))
|
|
return false;
|
|
|
|
// Write a relative jump to the redirected function.
|
|
WriteJumpInstruction(header, new_func);
|
|
|
|
// Write the short jump to the function prefix.
|
|
WriteShortJumpInstruction(old_func, header);
|
|
|
|
// Restore previous memory protection.
|
|
if (!RestoreMemoryProtection(header, patch_length, protection))
|
|
return false;
|
|
|
|
if (orig_old_func)
|
|
*orig_old_func = old_func + kShortJumpInstructionLength;
|
|
|
|
return true;
|
|
}
|
|
#endif
|
|
|
|
bool OverrideFunctionWithRedirectJump(
|
|
uptr old_func, uptr new_func, uptr *orig_old_func) {
|
|
// Check whether the first instruction is a relative jump.
|
|
if (*(u8*)old_func != 0xE9)
|
|
return false;
|
|
|
|
if (orig_old_func) {
|
|
sptr relative_offset = *(s32 *)(old_func + 1);
|
|
uptr absolute_target = old_func + relative_offset + kJumpInstructionLength;
|
|
*orig_old_func = absolute_target;
|
|
}
|
|
|
|
#if SANITIZER_WINDOWS64
|
|
// If needed, get memory space for a trampoline jump.
|
|
uptr trampoline = AllocateMemoryForTrampoline(old_func, kDirectBranchLength);
|
|
if (!trampoline)
|
|
return false;
|
|
WriteDirectBranch(trampoline, new_func);
|
|
#endif
|
|
|
|
// Change memory protection to writable.
|
|
DWORD protection = 0;
|
|
if (!ChangeMemoryProtection(old_func, kJumpInstructionLength, &protection))
|
|
return false;
|
|
|
|
// Write a relative jump to the redirected function.
|
|
WriteJumpInstruction(old_func, FIRST_32_SECOND_64(new_func, trampoline));
|
|
|
|
// Restore previous memory protection.
|
|
if (!RestoreMemoryProtection(old_func, kJumpInstructionLength, protection))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
bool OverrideFunctionWithHotPatch(
|
|
uptr old_func, uptr new_func, uptr *orig_old_func) {
|
|
const int kHotPatchHeaderLen = kBranchLength;
|
|
|
|
uptr header = (uptr)old_func - kHotPatchHeaderLen;
|
|
uptr patch_length = kHotPatchHeaderLen + kShortJumpInstructionLength;
|
|
|
|
// Validate that the function is hot patchable.
|
|
size_t instruction_size = GetInstructionSize(old_func);
|
|
if (instruction_size < kShortJumpInstructionLength ||
|
|
!FunctionHasPadding(old_func, kHotPatchHeaderLen))
|
|
return false;
|
|
|
|
if (orig_old_func) {
|
|
// Put the needed instructions into the trampoline bytes.
|
|
uptr trampoline_length = instruction_size + kDirectBranchLength;
|
|
uptr trampoline = AllocateMemoryForTrampoline(old_func, trampoline_length);
|
|
if (!trampoline)
|
|
return false;
|
|
if (!CopyInstructions(trampoline, old_func, instruction_size))
|
|
return false;
|
|
WriteDirectBranch(trampoline + instruction_size,
|
|
old_func + instruction_size);
|
|
*orig_old_func = trampoline;
|
|
}
|
|
|
|
// If needed, get memory space for indirect address.
|
|
uptr indirect_address = 0;
|
|
#if SANITIZER_WINDOWS64
|
|
indirect_address = AllocateMemoryForTrampoline(old_func, kAddressLength);
|
|
if (!indirect_address)
|
|
return false;
|
|
#endif
|
|
|
|
// Change memory protection to writable.
|
|
DWORD protection = 0;
|
|
if (!ChangeMemoryProtection(header, patch_length, &protection))
|
|
return false;
|
|
|
|
// Write jumps to the redirected function.
|
|
WriteBranch(header, indirect_address, new_func);
|
|
WriteShortJumpInstruction(old_func, header);
|
|
|
|
// Restore previous memory protection.
|
|
if (!RestoreMemoryProtection(header, patch_length, protection))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
bool OverrideFunctionWithTrampoline(
|
|
uptr old_func, uptr new_func, uptr *orig_old_func) {
|
|
|
|
size_t instructions_length = kBranchLength;
|
|
size_t padding_length = 0;
|
|
uptr indirect_address = 0;
|
|
|
|
if (orig_old_func) {
|
|
// Find out the number of bytes of the instructions we need to copy
|
|
// to the trampoline.
|
|
instructions_length = RoundUpToInstrBoundary(kBranchLength, old_func);
|
|
if (!instructions_length)
|
|
return false;
|
|
|
|
// Put the needed instructions into the trampoline bytes.
|
|
uptr trampoline_length = instructions_length + kDirectBranchLength;
|
|
uptr trampoline = AllocateMemoryForTrampoline(old_func, trampoline_length);
|
|
if (!trampoline)
|
|
return false;
|
|
if (!CopyInstructions(trampoline, old_func, instructions_length))
|
|
return false;
|
|
WriteDirectBranch(trampoline + instructions_length,
|
|
old_func + instructions_length);
|
|
*orig_old_func = trampoline;
|
|
}
|
|
|
|
#if SANITIZER_WINDOWS64
|
|
// Check if the targeted address can be encoded in the function padding.
|
|
// Otherwise, allocate it in the trampoline region.
|
|
if (IsMemoryPadding(old_func - kAddressLength, kAddressLength)) {
|
|
indirect_address = old_func - kAddressLength;
|
|
padding_length = kAddressLength;
|
|
} else {
|
|
indirect_address = AllocateMemoryForTrampoline(old_func, kAddressLength);
|
|
if (!indirect_address)
|
|
return false;
|
|
}
|
|
#endif
|
|
|
|
// Change memory protection to writable.
|
|
uptr patch_address = old_func - padding_length;
|
|
uptr patch_length = instructions_length + padding_length;
|
|
DWORD protection = 0;
|
|
if (!ChangeMemoryProtection(patch_address, patch_length, &protection))
|
|
return false;
|
|
|
|
// Patch the original function.
|
|
WriteBranch(old_func, indirect_address, new_func);
|
|
|
|
// Restore previous memory protection.
|
|
if (!RestoreMemoryProtection(patch_address, patch_length, protection))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
bool OverrideFunction(
|
|
uptr old_func, uptr new_func, uptr *orig_old_func) {
|
|
#if !SANITIZER_WINDOWS64
|
|
if (OverrideFunctionWithDetour(old_func, new_func, orig_old_func))
|
|
return true;
|
|
#endif
|
|
if (OverrideFunctionWithRedirectJump(old_func, new_func, orig_old_func))
|
|
return true;
|
|
if (OverrideFunctionWithHotPatch(old_func, new_func, orig_old_func))
|
|
return true;
|
|
if (OverrideFunctionWithTrampoline(old_func, new_func, orig_old_func))
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
static void **InterestingDLLsAvailable() {
|
|
static const char *InterestingDLLs[] = {
|
|
"kernel32.dll",
|
|
"msvcr100.dll", // VS2010
|
|
"msvcr110.dll", // VS2012
|
|
"msvcr120.dll", // VS2013
|
|
"vcruntime140.dll", // VS2015
|
|
"ucrtbase.dll", // Universal CRT
|
|
#if (defined(__MINGW32__) && defined(__i386__))
|
|
"libc++.dll", // libc++
|
|
"libunwind.dll", // libunwind
|
|
#endif
|
|
// 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];
|
|
if (export_directory->Size == 0)
|
|
return 0;
|
|
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]);
|
|
|
|
// Handle forwarded functions.
|
|
DWORD offset = functions[index];
|
|
if (offset >= export_directory->VirtualAddress &&
|
|
offset < export_directory->VirtualAddress + export_directory->Size) {
|
|
// An entry for a forwarded function is a string with the following
|
|
// format: "<module> . <function_name>" that is stored into the
|
|
// exported directory.
|
|
char function_name[256];
|
|
size_t funtion_name_length = _strlen(func);
|
|
if (funtion_name_length >= sizeof(function_name) - 1)
|
|
InterceptionFailed();
|
|
|
|
_memcpy(function_name, func, funtion_name_length);
|
|
function_name[funtion_name_length] = '\0';
|
|
char* separator = _strchr(function_name, '.');
|
|
if (!separator)
|
|
InterceptionFailed();
|
|
*separator = '\0';
|
|
|
|
void* redirected_module = GetModuleHandleA(function_name);
|
|
if (!redirected_module)
|
|
InterceptionFailed();
|
|
return InternalGetProcAddress(redirected_module, separator + 1);
|
|
}
|
|
|
|
return (uptr)(char *)func;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
bool OverrideFunction(
|
|
const char *func_name, uptr new_func, uptr *orig_old_func) {
|
|
bool hooked = false;
|
|
void **DLLs = InterestingDLLsAvailable();
|
|
for (size_t i = 0; DLLs[i]; ++i) {
|
|
uptr func_addr = InternalGetProcAddress(DLLs[i], func_name);
|
|
if (func_addr &&
|
|
OverrideFunction(func_addr, new_func, orig_old_func)) {
|
|
hooked = true;
|
|
}
|
|
}
|
|
return hooked;
|
|
}
|
|
|
|
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 // SANITIZER_APPLE
|