dll/appcompat/shims/shimlib/shimlib.c

   1 /*
   2  * PROJECT:     ReactOS Shim helper library
   3  * LICENSE:     GPL-2.0+ (https://spdx.org/licenses/GPL-2.0+)
   4  * PURPOSE:     Shim helper functions
   5  * COPYRIGHT:   Copyright 2016-2018 Mark Jansen (mark.jansen@reactos.org)
   6  */
   7
   8 #define WIN32_NO_STATUS
   9 #include <windef.h>
  10 #include <winbase.h>
  11 #include <shimlib.h>
  12 #include <strsafe.h>
  13 #include <ndk/rtlfuncs.h>
  14
  15 typedef struct UsedShim
  16 {
  17     SLIST_ENTRY Entry;
  18     PSHIMREG pShim;
  19 #if (WINVER > _WIN32_WINNT_WS03)
  20     BOOL bInitCalled;
  21 #endif
  22 } UsedShim, *pUsedShim;
  23
  24
  25 ULONG g_ShimEngDebugLevel = 0xffffffff;
  26 static HINSTANCE g_ShimLib_hInstance;
  27 static HANDLE g_ShimLib_Heap;
  28 static PSLIST_HEADER g_UsedShims;
  29
  30 void ShimLib_Init(HINSTANCE hInstance)
  31 {
  32     g_ShimLib_hInstance = hInstance;
  33     g_ShimLib_Heap = HeapCreate(0, 0x10000, 0);
  34
  35     g_UsedShims = (PSLIST_HEADER)ShimLib_ShimMalloc(sizeof(SLIST_HEADER));
  36     RtlInitializeSListHead(g_UsedShims);
  37 }
  38
  39 void ShimLib_Deinit(VOID)
  40 {
  41     // Is this a good idea?
  42     HeapDestroy(g_ShimLib_Heap);
  43 }
  44
  45 PVOID ShimLib_ShimMalloc(SIZE_T dwSize)
  46 {
  47     return HeapAlloc(g_ShimLib_Heap, 0, dwSize);
  48 }
  49
  50 void ShimLib_ShimFree(PVOID pData)
  51 {
  52     HeapFree(g_ShimLib_Heap, 0, pData);
  53 }
  54
  55 HINSTANCE ShimLib_Instance(VOID)
  56 {
  57     return g_ShimLib_hInstance;
  58 }
  59
  60 PCSTR ShimLib_StringNDuplicateA(PCSTR szString, SIZE_T stringLengthIncludingNullTerm)
  61 {
  62     PSTR NewString = ShimLib_ShimMalloc(stringLengthIncludingNullTerm);
  63     StringCchCopyA(NewString, stringLengthIncludingNullTerm, szString);
  64     return NewString;
  65 }
  66
  67 PCSTR ShimLib_StringDuplicateA(PCSTR szString)
  68 {
  69     return ShimLib_StringNDuplicateA(szString, lstrlenA(szString) + 1);
  70 }
  71
  72 BOOL ShimLib_StrAEqualsWNC(PCSTR szString, PCWSTR wszString)
  73 {
  74     while (toupper(*szString) == towupper(*wszString))
  75     {
  76         if (!*szString)
  77             return TRUE;
  78
  79         szString++; wszString++;
  80     }
  81     return FALSE;
  82 }
  83
  84 #if defined(_MSC_VER)
  85
  86 #if defined(_M_IA64) || defined(_M_AMD64)
  87 #define _ATTRIBUTES read
  88 #else
  89 #define _ATTRIBUTES read
  90 #endif
  91
  92
  93 #pragma section(".shm",long,read)
  94 #pragma section(".shm$AAA",long,read)
  95 #pragma section(".shm$ZZZ",long,read)
  96 #endif
  97
  98 #ifdef _MSC_VER
  99 #pragma comment(linker, "/merge:.shm=.rdata")
 100 #endif
 101
 102
 103 _SHMALLOC(".shm$AAA") SHIMREG _shim_start = { 0 };
 104 _SHMALLOC(".shm$ZZZ") SHIMREG _shim_end = { 0 };
 105
 106
 107 /* Generic GetHookAPIs function.
 108    The macro's from <setup_shim.inl> and <implement_shim.inl> will register a list of all apis that should be hooked
 109    for a specific shim
 110    This helper function will return the correct shim, and call the init function */
 111 PHOOKAPI WINAPI ShimLib_GetHookAPIs(IN LPCSTR szCommandLine, IN LPCWSTR wszShimName, OUT PDWORD pdwHookCount)
 112 {
 113     PSHIMREG ps = &_shim_start;
 114     ps++;
 115     for (; ps < &_shim_end; ps++)
 116     {
 117         if (ps->GetHookAPIs != NULL && ps->ShimName != NULL)
 118         {
 119             if (ShimLib_StrAEqualsWNC(ps->ShimName, wszShimName))
 120             {
 121                 pUsedShim shim = (pUsedShim)ShimLib_ShimMalloc(sizeof(UsedShim));
 122                 shim->pShim = ps;
 123 #if (WINVER > _WIN32_WINNT_WS03)
 124                 shim->bInitCalled = FALSE;
 125 #endif
 126                 RtlInterlockedPushEntrySList(g_UsedShims, &(shim->Entry));
 127
 128                 return ps->GetHookAPIs(SHIM_NOTIFY_ATTACH, szCommandLine, pdwHookCount);
 129             }
 130         }
 131     }
 132     return NULL;
 133 }
 134
 135
 136 BOOL WINAPI ShimLib_NotifyShims(DWORD fdwReason, PVOID ptr)
 137 {
 138     PSLIST_ENTRY pEntry = RtlFirstEntrySList(g_UsedShims);
 139
 140     if (fdwReason < SHIM_REASON_INIT)
 141         fdwReason += (SHIM_REASON_INIT - SHIM_NOTIFY_ATTACH);
 142
 143     while (pEntry)
 144     {
 145         pUsedShim pUsed = CONTAINING_RECORD(pEntry, UsedShim, Entry);
 146         _PVNotify Notify = pUsed->pShim->Notify;
 147 #if (WINVER > _WIN32_WINNT_WS03)
 148         if (pUsed->bInitCalled && fdwReason == SHIM_REASON_INIT)
 149             Notify = NULL;
 150 #endif
 151         if (Notify)
 152             Notify(fdwReason, ptr);
 153 #if (WINVER > _WIN32_WINNT_WS03)
 154         if (fdwReason == SHIM_REASON_INIT)
 155             pUsed->bInitCalled = TRUE;
 156 #endif
 157
 158         pEntry = pEntry->Next;
 159     }
 160
 161     return TRUE;
 162 }
 163
 164
 165 VOID SeiInitDebugSupport(VOID)
 166 {
 167     static const UNICODE_STRING DebugKey = RTL_CONSTANT_STRING(L"SHIM_DEBUG_LEVEL");
 168     UNICODE_STRING DebugValue;
 169     NTSTATUS Status;
 170     ULONG NewLevel = SEI_MSG;
 171     WCHAR Buffer[40];
 172
 173     RtlInitEmptyUnicodeString(&DebugValue, Buffer, sizeof(Buffer));
 174
 175     Status = RtlQueryEnvironmentVariable_U(NULL, &DebugKey, &DebugValue);
 176
 177     if (NT_SUCCESS(Status))
 178     {
 179         if (!NT_SUCCESS(RtlUnicodeStringToInteger(&DebugValue, 10, &NewLevel)))
 180             NewLevel = 0;
 181     }
 182     g_ShimEngDebugLevel = NewLevel;
 183 }
 184
 185
 186 /**
 187 * Outputs diagnostic info.
 188 *
 189 * @param [in]  Level           The level to log this message with, choose any of [SHIM_ERR,
 190 *                              SHIM_WARN, SHIM_INFO].
 191 * @param [in]  FunctionName    The function this log should be attributed to.
 192 * @param [in]  Format          The format string.
 193 * @param   ...                 Variable arguments providing additional information.
 194 *
 195 * @return  Success: TRUE Failure: FALSE.
 196 */
 197 BOOL WINAPIV SeiDbgPrint(SEI_LOG_LEVEL Level, PCSTR Function, PCSTR Format, ...)
 198 {
 199     char Buffer[512];
 200     char* Current = Buffer;
 201     const char* LevelStr;
 202     size_t Length = sizeof(Buffer);
 203     va_list ArgList;
 204     HRESULT hr;
 205
 206     if (g_ShimEngDebugLevel == 0xffffffff)
 207         SeiInitDebugSupport();
 208
 209     if (Level > g_ShimEngDebugLevel)
 210         return FALSE;
 211
 212     switch (Level)
 213     {
 214     case SEI_MSG:
 215         LevelStr = "MSG ";
 216         break;
 217     case SEI_FAIL:
 218         LevelStr = "FAIL";
 219         break;
 220     case SEI_WARN:
 221         LevelStr = "WARN";
 222         break;
 223     case SEI_INFO:
 224         LevelStr = "INFO";
 225         break;
 226     default:
 227         LevelStr = "USER";
 228         break;
 229     }
 230
 231     if (Function)
 232         hr = StringCchPrintfExA(Current, Length, &Current, &Length, STRSAFE_NULL_ON_FAILURE, "[%s] [%s] ", LevelStr, Function);
 233     else
 234         hr = StringCchPrintfExA(Current, Length, &Current, &Length, STRSAFE_NULL_ON_FAILURE, "[%s] ", LevelStr);
 235
 236     if (!SUCCEEDED(hr))
 237         return FALSE;
 238
 239     va_start(ArgList, Format);
 240     hr = StringCchVPrintfExA(Current, Length, &Current, &Length, STRSAFE_NULL_ON_FAILURE, Format, ArgList);
 241     va_end(ArgList);
 242     if (!SUCCEEDED(hr))
 243         return FALSE;
 244
 245     DbgPrint("%s", Buffer);
 246     return TRUE;
 247 }
 248