diff options
Diffstat (limited to 'chromium/sandbox/win/src/service_resolver_32.cc')
| -rw-r--r-- | chromium/sandbox/win/src/service_resolver_32.cc | 420 |
1 files changed, 420 insertions, 0 deletions
diff --git a/chromium/sandbox/win/src/service_resolver_32.cc b/chromium/sandbox/win/src/service_resolver_32.cc new file mode 100644 index 00000000000..2e69dbc9e7e --- /dev/null +++ b/chromium/sandbox/win/src/service_resolver_32.cc @@ -0,0 +1,420 @@ +// Copyright (c) 2012 The Chromium Authors. All rights reserved. +// Use of this source code is governed by a BSD-style license that can be +// found in the LICENSE file. + +#include "sandbox/win/src/service_resolver.h" + +#include "base/memory/scoped_ptr.h" +#include "sandbox/win/src/win_utils.h" + +namespace { +#pragma pack(push, 1) + +const BYTE kMovEax = 0xB8; +const BYTE kMovEdx = 0xBA; +const USHORT kMovEdxEsp = 0xD48B; +const USHORT kCallPtrEdx = 0x12FF; +const USHORT kCallEdx = 0xD2FF; +const BYTE kCallEip = 0xE8; +const BYTE kRet = 0xC2; +const BYTE kRet2 = 0xC3; +const BYTE kNop = 0x90; +const USHORT kJmpEdx = 0xE2FF; +const USHORT kXorEcx = 0xC933; +const ULONG kLeaEdx = 0x0424548D; +const ULONG kCallFs1 = 0xC015FF64; +const USHORT kCallFs2 = 0; +const BYTE kCallFs3 = 0; +const BYTE kAddEsp1 = 0x83; +const USHORT kAddEsp2 = 0x4C4; +const BYTE kJmp32 = 0xE9; +const USHORT kSysenter = 0x340F; + +const int kMaxService = 1000; + +// Service code for 32 bit systems. +// NOTE: on win2003 "call dword ptr [edx]" is "call edx". +struct ServiceEntry { + // This struct contains roughly the following code: + // 00 mov eax,25h + // 05 mov edx,offset SharedUserData!SystemCallStub (7ffe0300) + // 0a call dword ptr [edx] + // 0c ret 2Ch + // 0f nop + BYTE mov_eax; // = B8 + ULONG service_id; + BYTE mov_edx; // = BA + ULONG stub; + USHORT call_ptr_edx; // = FF 12 + BYTE ret; // = C2 + USHORT num_params; + BYTE nop; +}; + +// Service code for 32 bit Windows 8. +struct ServiceEntryW8 { + // This struct contains the following code: + // 00 b825000000 mov eax,25h + // 05 e803000000 call eip+3 + // 0a c22c00 ret 2Ch + // 0d 8bd4 mov edx,esp + // 0f 0f34 sysenter + // 11 c3 ret + // 12 8bff mov edi,edi + BYTE mov_eax; // = B8 + ULONG service_id; + BYTE call_eip; // = E8 + ULONG call_offset; + BYTE ret_p; // = C2 + USHORT num_params; + USHORT mov_edx_esp; // = BD D4 + USHORT sysenter; // = 0F 34 + BYTE ret; // = C3 + USHORT nop; +}; + +// Service code for a 32 bit process running on a 64 bit os. +struct Wow64Entry { + // This struct may contain one of two versions of code: + // 1. For XP, Vista and 2K3: + // 00 b825000000 mov eax, 25h + // 05 33c9 xor ecx, ecx + // 07 8d542404 lea edx, [esp + 4] + // 0b 64ff15c0000000 call dword ptr fs:[0C0h] + // 12 c22c00 ret 2Ch + // + // 2. For Windows 7: + // 00 b825000000 mov eax, 25h + // 05 33c9 xor ecx, ecx + // 07 8d542404 lea edx, [esp + 4] + // 0b 64ff15c0000000 call dword ptr fs:[0C0h] + // 12 83c404 add esp, 4 + // 15 c22c00 ret 2Ch + // + // So we base the structure on the bigger one: + BYTE mov_eax; // = B8 + ULONG service_id; + USHORT xor_ecx; // = 33 C9 + ULONG lea_edx; // = 8D 54 24 04 + ULONG call_fs1; // = 64 FF 15 C0 + USHORT call_fs2; // = 00 00 + BYTE call_fs3; // = 00 + BYTE add_esp1; // = 83 or ret + USHORT add_esp2; // = C4 04 or num_params + BYTE ret; // = C2 + USHORT num_params; +}; + +// Service code for a 32 bit process running on 64 bit Windows 8. +struct Wow64EntryW8 { + // 00 b825000000 mov eax, 25h + // 05 64ff15c0000000 call dword ptr fs:[0C0h] + // 0b c22c00 ret 2Ch + // 0f 90 nop + BYTE mov_eax; // = B8 + ULONG service_id; + ULONG call_fs1; // = 64 FF 15 C0 + USHORT call_fs2; // = 00 00 + BYTE call_fs3; // = 00 + BYTE ret; // = C2 + USHORT num_params; + BYTE nop; +}; + +// Make sure that relaxed patching works as expected. +const size_t kMinServiceSize = offsetof(ServiceEntry, ret); +COMPILE_ASSERT(sizeof(ServiceEntryW8) >= kMinServiceSize, wrong_service_len); +COMPILE_ASSERT(sizeof(Wow64Entry) >= kMinServiceSize, wrong_service_len); +COMPILE_ASSERT(sizeof(Wow64EntryW8) >= kMinServiceSize, wrong_service_len); + +struct ServiceFullThunk { + union { + ServiceEntry original; + ServiceEntryW8 original_w8; + Wow64Entry wow_64; + Wow64EntryW8 wow_64_w8; + }; + int internal_thunk; // Dummy member to the beginning of the internal thunk. +}; + +#pragma pack(pop) + +}; // namespace + +namespace sandbox { + +NTSTATUS ServiceResolverThunk::Setup(const void* target_module, + const void* interceptor_module, + const char* target_name, + const char* interceptor_name, + const void* interceptor_entry_point, + void* thunk_storage, + size_t storage_bytes, + size_t* storage_used) { + NTSTATUS ret = Init(target_module, interceptor_module, target_name, + interceptor_name, interceptor_entry_point, + thunk_storage, storage_bytes); + if (!NT_SUCCESS(ret)) + return ret; + + relative_jump_ = 0; + size_t thunk_bytes = GetThunkSize(); + scoped_ptr<char[]> thunk_buffer(new char[thunk_bytes]); + ServiceFullThunk* thunk = reinterpret_cast<ServiceFullThunk*>( + thunk_buffer.get()); + + if (!IsFunctionAService(&thunk->original) && + (!relaxed_ || !SaveOriginalFunction(&thunk->original, thunk_storage))) + return STATUS_UNSUCCESSFUL; + + ret = PerformPatch(thunk, thunk_storage); + + if (NULL != storage_used) + *storage_used = thunk_bytes; + + return ret; +} + +size_t ServiceResolverThunk::GetThunkSize() const { + return offsetof(ServiceFullThunk, internal_thunk) + GetInternalThunkSize(); +} + +bool ServiceResolverThunk::IsFunctionAService(void* local_thunk) const { + ServiceEntry function_code; + SIZE_T read; + if (!::ReadProcessMemory(process_, target_, &function_code, + sizeof(function_code), &read)) + return false; + + if (sizeof(function_code) != read) + return false; + + if (kMovEax != function_code.mov_eax || + kMovEdx != function_code.mov_edx || + (kCallPtrEdx != function_code.call_ptr_edx && + kCallEdx != function_code.call_ptr_edx) || + kRet != function_code.ret) + return false; + + // Find the system call pointer if we don't already have it. + if (kCallEdx != function_code.call_ptr_edx) { + DWORD ki_system_call; + if (!::ReadProcessMemory(process_, + bit_cast<const void*>(function_code.stub), + &ki_system_call, sizeof(ki_system_call), &read)) + return false; + + if (sizeof(ki_system_call) != read) + return false; + + HMODULE module_1, module_2; + // last check, call_stub should point to a KiXXSystemCall function on ntdll + if (!GetModuleHandleEx(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS | + GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT, + bit_cast<const wchar_t*>(ki_system_call), &module_1)) + return false; + + if (NULL != ntdll_base_) { + // This path is only taken when running the unit tests. We want to be + // able to patch a buffer in memory, so target_ is not inside ntdll. + module_2 = ntdll_base_; + } else { + if (!GetModuleHandleEx(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS | + GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT, + reinterpret_cast<const wchar_t*>(target_), + &module_2)) + return false; + } + + if (module_1 != module_2) + return false; + } + + // Save the verified code + memcpy(local_thunk, &function_code, sizeof(function_code)); + + return true; +} + +NTSTATUS ServiceResolverThunk::PerformPatch(void* local_thunk, + void* remote_thunk) { + ServiceEntry intercepted_code; + size_t bytes_to_write = sizeof(intercepted_code); + ServiceFullThunk *full_local_thunk = reinterpret_cast<ServiceFullThunk*>( + local_thunk); + ServiceFullThunk *full_remote_thunk = reinterpret_cast<ServiceFullThunk*>( + remote_thunk); + + // patch the original code + memcpy(&intercepted_code, &full_local_thunk->original, + sizeof(intercepted_code)); + intercepted_code.mov_eax = kMovEax; + intercepted_code.service_id = full_local_thunk->original.service_id; + intercepted_code.mov_edx = kMovEdx; + intercepted_code.stub = bit_cast<ULONG>(&full_remote_thunk->internal_thunk); + intercepted_code.call_ptr_edx = kJmpEdx; + bytes_to_write = kMinServiceSize; + + if (relative_jump_) { + intercepted_code.mov_eax = kJmp32; + intercepted_code.service_id = relative_jump_; + bytes_to_write = offsetof(ServiceEntry, mov_edx); + } + + // setup the thunk + SetInternalThunk(&full_local_thunk->internal_thunk, GetInternalThunkSize(), + remote_thunk, interceptor_); + + size_t thunk_size = GetThunkSize(); + + // copy the local thunk buffer to the child + SIZE_T written; + if (!::WriteProcessMemory(process_, remote_thunk, local_thunk, + thunk_size, &written)) + return STATUS_UNSUCCESSFUL; + + if (thunk_size != written) + return STATUS_UNSUCCESSFUL; + + // and now change the function to intercept, on the child + if (NULL != ntdll_base_) { + // running a unit test + if (!::WriteProcessMemory(process_, target_, &intercepted_code, + bytes_to_write, &written)) + return STATUS_UNSUCCESSFUL; + } else { + if (!WriteProtectedChildMemory(process_, target_, &intercepted_code, + bytes_to_write)) + return STATUS_UNSUCCESSFUL; + } + + return STATUS_SUCCESS; +} + +bool ServiceResolverThunk::SaveOriginalFunction(void* local_thunk, + void* remote_thunk) { + ServiceEntry function_code; + SIZE_T read; + if (!::ReadProcessMemory(process_, target_, &function_code, + sizeof(function_code), &read)) + return false; + + if (sizeof(function_code) != read) + return false; + + if (kJmp32 == function_code.mov_eax) { + // Plain old entry point patch. The relative jump address follows it. + ULONG relative = function_code.service_id; + + // First, fix our copy of their patch. + relative += bit_cast<ULONG>(target_) - bit_cast<ULONG>(remote_thunk); + + function_code.service_id = relative; + + // And now, remember how to re-patch it. + ServiceFullThunk *full_thunk = + reinterpret_cast<ServiceFullThunk*>(remote_thunk); + + const ULONG kJmp32Size = 5; + + relative_jump_ = bit_cast<ULONG>(&full_thunk->internal_thunk) - + bit_cast<ULONG>(target_) - kJmp32Size; + } + + // Save the verified code + memcpy(local_thunk, &function_code, sizeof(function_code)); + + return true; +} + +bool Wow64ResolverThunk::IsFunctionAService(void* local_thunk) const { + Wow64Entry function_code; + SIZE_T read; + if (!::ReadProcessMemory(process_, target_, &function_code, + sizeof(function_code), &read)) + return false; + + if (sizeof(function_code) != read) + return false; + + if (kMovEax != function_code.mov_eax || kXorEcx != function_code.xor_ecx || + kLeaEdx != function_code.lea_edx || kCallFs1 != function_code.call_fs1 || + kCallFs2 != function_code.call_fs2 || kCallFs3 != function_code.call_fs3) + return false; + + if ((kAddEsp1 == function_code.add_esp1 && + kAddEsp2 == function_code.add_esp2 && + kRet == function_code.ret) || kRet == function_code.add_esp1) { + // Save the verified code + memcpy(local_thunk, &function_code, sizeof(function_code)); + return true; + } + + return false; +} + +bool Wow64W8ResolverThunk::IsFunctionAService(void* local_thunk) const { + Wow64EntryW8 function_code; + SIZE_T read; + if (!::ReadProcessMemory(process_, target_, &function_code, + sizeof(function_code), &read)) + return false; + + if (sizeof(function_code) != read) + return false; + + if (kMovEax != function_code.mov_eax || kCallFs1 != function_code.call_fs1 || + kCallFs2 != function_code.call_fs2 || + kCallFs3 != function_code.call_fs3 || kRet != function_code.ret) { + return false; + } + + // Save the verified code + memcpy(local_thunk, &function_code, sizeof(function_code)); + return true; +} + +bool Win2kResolverThunk::IsFunctionAService(void* local_thunk) const { + ServiceEntry function_code; + SIZE_T read; + if (!::ReadProcessMemory(process_, target_, &function_code, + sizeof(function_code), &read)) + return false; + + if (sizeof(function_code) != read) + return false; + + if (kMovEax != function_code.mov_eax || + function_code.service_id > kMaxService) + return false; + + // Save the verified code + memcpy(local_thunk, &function_code, sizeof(function_code)); + + return true; +} + +bool Win8ResolverThunk::IsFunctionAService(void* local_thunk) const { + ServiceEntryW8 function_code; + SIZE_T read; + if (!::ReadProcessMemory(process_, target_, &function_code, + sizeof(function_code), &read)) + return false; + + if (sizeof(function_code) != read) + return false; + + if (kMovEax != function_code.mov_eax || kCallEip != function_code.call_eip || + function_code.call_offset != 3 || kRet != function_code.ret_p || + kMovEdxEsp != function_code.mov_edx_esp || + kSysenter != function_code.sysenter || kRet2 != function_code.ret) { + return false; + } + + // Save the verified code + memcpy(local_thunk, &function_code, sizeof(function_code)); + + return true; +} + +} // namespace sandbox |