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 2016,2017 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 HANDLE g_ShimLib_Heap;
  27 static PSLIST_HEADER g_UsedShims;
  28
  29 void ShimLib_Init(HINSTANCE hInstance)
  30 {
  31     g_ShimLib_Heap = HeapCreate(0, 0x10000, 0);
  32
  33     g_UsedShims = (PSLIST_HEADER)ShimLib_ShimMalloc(sizeof(SLIST_HEADER));
  34     RtlInitializeSListHead(g_UsedShims);
  35 }
  36
  37 void ShimLib_Deinit()
  38 {
  39     // Is this a good idea?
  40     HeapDestroy(g_ShimLib_Heap);
  41 }
  42
  43 PVOID ShimLib_ShimMalloc(SIZE_T dwSize)
  44 {
  45     return HeapAlloc(g_ShimLib_Heap, 0, dwSize);
  46 }
  47
  48 void ShimLib_ShimFree(PVOID pData)
  49 {
  50     HeapFree(g_ShimLib_Heap, 0, pData);
  51 }
  52
  53 PCSTR ShimLib_StringDuplicateA(PCSTR szString)
  54 {
  55     SIZE_T Length = lstrlenA(szString);
  56     PSTR NewString = ShimLib_ShimMalloc(Length+1);
  57     return lstrcpyA(NewString, szString);
  58 }
  59
  60 BOOL ShimLib_StrAEqualsW(PCSTR szString, PCWSTR wszString)
  61 {
  62     while (*szString == *wszString)
  63     {
  64         if (!*szString)
  65             return TRUE;
  66
  67         szString++; wszString++;
  68     }
  69     return FALSE;
  70 }
  71
  72 #if defined(_MSC_VER)
  73
  74 #if defined(_M_IA64) || defined(_M_AMD64)
  75 #define _ATTRIBUTES read
  76 #else
  77 #define _ATTRIBUTES read
  78 #endif
  79
  80
  81 #pragma section(".shm",long,read)
  82 #pragma section(".shm$AAA",long,read)
  83 #pragma section(".shm$ZZZ",long,read)
  84 #endif
  85
  86 #ifdef _MSC_VER
  87 #pragma comment(linker, "/merge:.shm=.rdata")
  88 #endif
  89
  90
  91 _SHMALLOC(".shm") SHIMREG _shim_start = { 0 };
  92 _SHMALLOC(".shm$ZZZ") SHIMREG _shim_end = { 0 };
  93
  94
  95 /* Generic GetHookAPIs function.
  96    The macro's from <setup_shim.inl> and <implement_shim.inl> will register a list of all apis that should be hooked
  97    for a specific shim
  98    This helper function will return the correct shim, and call the init function */
  99 PHOOKAPI WINAPI ShimLib_GetHookAPIs(IN LPCSTR szCommandLine, IN LPCWSTR wszShimName, OUT PDWORD pdwHookCount)
 100 {
 101     PSHIMREG ps = &_shim_start;
 102     ps++;
 103     for (; ps != &_shim_end; ps++)
 104     {
 105         if (ps->GetHookAPIs != NULL && ps->ShimName != NULL)
 106         {
 107             if (ShimLib_StrAEqualsW(ps->ShimName, wszShimName))
 108             {
 109                 pUsedShim shim = (pUsedShim)ShimLib_ShimMalloc(sizeof(UsedShim));
 110                 shim->pShim = ps;
 111 #if (WINVER > _WIN32_WINNT_WS03)
 112                 shim->bInitCalled = FALSE;
 113 #endif
 114                 RtlInterlockedPushEntrySList(g_UsedShims, &(shim->Entry));
 115
 116                 return ps->GetHookAPIs(SHIM_NOTIFY_ATTACH, szCommandLine, pdwHookCount);
 117             }
 118         }
 119     }
 120     return NULL;
 121 }
 122
 123
 124 BOOL WINAPI ShimLib_NotifyShims(DWORD fdwReason, PVOID ptr)
 125 {
 126     PSLIST_ENTRY pEntry = RtlFirstEntrySList(g_UsedShims);
 127
 128     if (fdwReason < SHIM_REASON_INIT)
 129         fdwReason += (SHIM_REASON_INIT - SHIM_NOTIFY_ATTACH);
 130
 131     while (pEntry)
 132     {
 133         pUsedShim pUsed = CONTAINING_RECORD(pEntry, UsedShim, Entry);
 134         _PVNotify Notify = pUsed->pShim->Notify;
 135 #if (WINVER > _WIN32_WINNT_WS03)
 136         if (pUsed->bInitCalled && fdwReason == SHIM_REASON_INIT)
 137             Notify = NULL;
 138 #endif
 139         if (Notify)
 140             Notify(fdwReason, ptr);
 141 #if (WINVER > _WIN32_WINNT_WS03)
 142         if (fdwReason == SHIM_REASON_INIT)
 143             pUsed->bInitCalled = TRUE;
 144 #endif
 145
 146         pEntry = pEntry->Next;
 147     }
 148
 149     return TRUE;
 150 }
 151
 152
 153 VOID SeiInitDebugSupport(VOID)
 154 {
 155     static const UNICODE_STRING DebugKey = RTL_CONSTANT_STRING(L"SHIM_DEBUG_LEVEL");
 156     UNICODE_STRING DebugValue;
 157     NTSTATUS Status;
 158     ULONG NewLevel = 0;
 159     WCHAR Buffer[40];
 160
 161     RtlInitEmptyUnicodeString(&DebugValue, Buffer, sizeof(Buffer));
 162
 163     Status = RtlQueryEnvironmentVariable_U(NULL, &DebugKey, &DebugValue);
 164
 165     if (NT_SUCCESS(Status))
 166     {
 167         if (!NT_SUCCESS(RtlUnicodeStringToInteger(&DebugValue, 10, &NewLevel)))
 168             NewLevel = 0;
 169     }
 170     g_ShimEngDebugLevel = NewLevel;
 171 }
 172
 173
 174 /**
 175 * Outputs diagnostic info.
 176 *
 177 * @param [in]  Level           The level to log this message with, choose any of [SHIM_ERR,
 178 *                              SHIM_WARN, SHIM_INFO].
 179 * @param [in]  FunctionName    The function this log should be attributed to.
 180 * @param [in]  Format          The format string.
 181 * @param   ...                 Variable arguments providing additional information.
 182 *
 183 * @return  Success: TRUE Failure: FALSE.
 184 */
 185 BOOL WINAPIV SeiDbgPrint(SEI_LOG_LEVEL Level, PCSTR Function, PCSTR Format, ...)
 186 {
 187     char Buffer[512];
 188     char* Current = Buffer;
 189     const char* LevelStr;
 190     size_t Length = sizeof(Buffer);
 191     va_list ArgList;
 192     HRESULT hr;
 193
 194     if (g_ShimEngDebugLevel == 0xffffffff)
 195         SeiInitDebugSupport();
 196
 197     if (Level > g_ShimEngDebugLevel)
 198         return FALSE;
 199
 200     switch (Level)
 201     {
 202     case SEI_MSG:
 203         LevelStr = "MSG ";
 204         break;
 205     case SEI_FAIL:
 206         LevelStr = "FAIL";
 207         break;
 208     case SEI_WARN:
 209         LevelStr = "WARN";
 210         break;
 211     case SEI_INFO:
 212         LevelStr = "INFO";
 213         break;
 214     default:
 215         LevelStr = "USER";
 216         break;
 217     }
 218
 219     if (Function)
 220         hr = StringCchPrintfExA(Current, Length, &Current, &Length, STRSAFE_NULL_ON_FAILURE, "[%s] [%s] ", LevelStr, Function);
 221     else
 222         hr = StringCchPrintfExA(Current, Length, &Current, &Length, STRSAFE_NULL_ON_FAILURE, "[%s] ", LevelStr);
 223
 224     if (!SUCCEEDED(hr))
 225         return FALSE;
 226
 227     va_start(ArgList, Format);
 228     hr = StringCchVPrintfExA(Current, Length, &Current, &Length, STRSAFE_NULL_ON_FAILURE, Format, ArgList);
 229     va_end(ArgList);
 230     if (!SUCCEEDED(hr))
 231         return FALSE;
 232
 233     DbgPrint("%s", Buffer);
 234     return TRUE;
 235 }
 236