1 //===- FuzzerIOWindows.cpp - IO utils for Windows. ------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 // IO functions implementation for Windows.
9 //===----------------------------------------------------------------------===//
10 #include "FuzzerPlatform.h"
11 #if LIBFUZZER_WINDOWS
12 
13 #include "FuzzerExtFunctions.h"
14 #include "FuzzerIO.h"
15 #include <cstdarg>
16 #include <cstdio>
17 #include <fstream>
18 #include <io.h>
19 #include <iterator>
20 #include <sys/stat.h>
21 #include <sys/types.h>
22 #include <windows.h>
23 
24 namespace fuzzer {
25 
26 static bool IsFile(const std::string &Path, const DWORD &FileAttributes) {
27 
28   if (FileAttributes & FILE_ATTRIBUTE_NORMAL)
29     return true;
30 
31   if (FileAttributes & FILE_ATTRIBUTE_DIRECTORY)
32     return false;
33 
34   HANDLE FileHandle(
35       CreateFileA(Path.c_str(), 0, FILE_SHARE_READ, NULL, OPEN_EXISTING,
36                   FILE_FLAG_BACKUP_SEMANTICS, 0));
37 
38   if (FileHandle == INVALID_HANDLE_VALUE) {
39     Printf("CreateFileA() failed for \"%s\" (Error code: %lu).\n", Path.c_str(),
40         GetLastError());
41     return false;
42   }
43 
44   DWORD FileType = GetFileType(FileHandle);
45 
46   if (FileType == FILE_TYPE_UNKNOWN) {
47     Printf("GetFileType() failed for \"%s\" (Error code: %lu).\n", Path.c_str(),
48         GetLastError());
49     CloseHandle(FileHandle);
50     return false;
51   }
52 
53   if (FileType != FILE_TYPE_DISK) {
54     CloseHandle(FileHandle);
55     return false;
56   }
57 
58   CloseHandle(FileHandle);
59   return true;
60 }
61 
62 bool IsFile(const std::string &Path) {
63   DWORD Att = GetFileAttributesA(Path.c_str());
64 
65   if (Att == INVALID_FILE_ATTRIBUTES) {
66     Printf("GetFileAttributesA() failed for \"%s\" (Error code: %lu).\n",
67         Path.c_str(), GetLastError());
68     return false;
69   }
70 
71   return IsFile(Path, Att);
72 }
73 
74 static bool IsDir(DWORD FileAttrs) {
75   if (FileAttrs == INVALID_FILE_ATTRIBUTES) return false;
76   return FileAttrs & FILE_ATTRIBUTE_DIRECTORY;
77 }
78 
79 bool IsDirectory(const std::string &Path) {
80   DWORD Att = GetFileAttributesA(Path.c_str());
81 
82   if (Att == INVALID_FILE_ATTRIBUTES) {
83     Printf("GetFileAttributesA() failed for \"%s\" (Error code: %lu).\n",
84            Path.c_str(), GetLastError());
85     return false;
86   }
87 
88   return IsDir(Att);
89 }
90 
91 std::string Basename(const std::string &Path) {
92   size_t Pos = Path.find_last_of("/\\");
93   if (Pos == std::string::npos) return Path;
94   assert(Pos < Path.size());
95   return Path.substr(Pos + 1);
96 }
97 
98 size_t FileSize(const std::string &Path) {
99   WIN32_FILE_ATTRIBUTE_DATA attr;
100   if (!GetFileAttributesExA(Path.c_str(), GetFileExInfoStandard, &attr)) {
101     DWORD LastError = GetLastError();
102     if (LastError != ERROR_FILE_NOT_FOUND)
103       Printf("GetFileAttributesExA() failed for \"%s\" (Error code: %lu).\n",
104              Path.c_str(), LastError);
105     return 0;
106   }
107   ULARGE_INTEGER size;
108   size.HighPart = attr.nFileSizeHigh;
109   size.LowPart = attr.nFileSizeLow;
110   return size.QuadPart;
111 }
112 
113 void ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
114                              std::vector<std::string> *V, bool TopDir) {
115   auto E = GetEpoch(Dir);
116   if (Epoch)
117     if (E && *Epoch >= E) return;
118 
119   std::string Path(Dir);
120   assert(!Path.empty());
121   if (Path.back() != '\\')
122       Path.push_back('\\');
123   Path.push_back('*');
124 
125   // Get the first directory entry.
126   WIN32_FIND_DATAA FindInfo;
127   HANDLE FindHandle(FindFirstFileA(Path.c_str(), &FindInfo));
128   if (FindHandle == INVALID_HANDLE_VALUE)
129   {
130     if (GetLastError() == ERROR_FILE_NOT_FOUND)
131       return;
132     Printf("No such file or directory: %s; exiting\n", Dir.c_str());
133     exit(1);
134   }
135 
136   do {
137     std::string FileName = DirPlusFile(Dir, FindInfo.cFileName);
138 
139     if (FindInfo.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) {
140       size_t FilenameLen = strlen(FindInfo.cFileName);
141       if ((FilenameLen == 1 && FindInfo.cFileName[0] == '.') ||
142           (FilenameLen == 2 && FindInfo.cFileName[0] == '.' &&
143                                FindInfo.cFileName[1] == '.'))
144         continue;
145 
146       ListFilesInDirRecursive(FileName, Epoch, V, false);
147     }
148     else if (IsFile(FileName, FindInfo.dwFileAttributes))
149       V->push_back(FileName);
150   } while (FindNextFileA(FindHandle, &FindInfo));
151 
152   DWORD LastError = GetLastError();
153   if (LastError != ERROR_NO_MORE_FILES)
154     Printf("FindNextFileA failed (Error code: %lu).\n", LastError);
155 
156   FindClose(FindHandle);
157 
158   if (Epoch && TopDir)
159     *Epoch = E;
160 }
161 
162 void IterateDirRecursive(const std::string &Dir,
163                          void (*DirPreCallback)(const std::string &Dir),
164                          void (*DirPostCallback)(const std::string &Dir),
165                          void (*FileCallback)(const std::string &Dir)) {
166   // TODO(metzman): Implement ListFilesInDirRecursive via this function.
167   DirPreCallback(Dir);
168 
169   DWORD DirAttrs = GetFileAttributesA(Dir.c_str());
170   if (!IsDir(DirAttrs)) return;
171 
172   std::string TargetDir(Dir);
173   assert(!TargetDir.empty());
174   if (TargetDir.back() != '\\') TargetDir.push_back('\\');
175   TargetDir.push_back('*');
176 
177   WIN32_FIND_DATAA FindInfo;
178   // Find the directory's first file.
179   HANDLE FindHandle = FindFirstFileA(TargetDir.c_str(), &FindInfo);
180   if (FindHandle == INVALID_HANDLE_VALUE) {
181     DWORD LastError = GetLastError();
182     if (LastError != ERROR_FILE_NOT_FOUND) {
183       // If the directory isn't empty, then something abnormal is going on.
184       Printf("FindFirstFileA failed for %s (Error code: %lu).\n", Dir.c_str(),
185              LastError);
186     }
187     return;
188   }
189 
190   do {
191     std::string Path = DirPlusFile(Dir, FindInfo.cFileName);
192     DWORD PathAttrs = FindInfo.dwFileAttributes;
193     if (IsDir(PathAttrs)) {
194       // Is Path the current directory (".") or the parent ("..")?
195       if (strcmp(FindInfo.cFileName, ".") == 0 ||
196           strcmp(FindInfo.cFileName, "..") == 0)
197         continue;
198       IterateDirRecursive(Path, DirPreCallback, DirPostCallback, FileCallback);
199     } else if (PathAttrs != INVALID_FILE_ATTRIBUTES) {
200       FileCallback(Path);
201     }
202   } while (FindNextFileA(FindHandle, &FindInfo));
203 
204   DWORD LastError = GetLastError();
205   if (LastError != ERROR_NO_MORE_FILES)
206     Printf("FindNextFileA failed for %s (Error code: %lu).\n", Dir.c_str(),
207            LastError);
208 
209   FindClose(FindHandle);
210   DirPostCallback(Dir);
211 }
212 
213 char GetSeparator() {
214   return '\\';
215 }
216 
217 FILE* OpenFile(int Fd, const char* Mode) {
218   return _fdopen(Fd, Mode);
219 }
220 
221 int CloseFile(int Fd) {
222   return _close(Fd);
223 }
224 
225 int DuplicateFile(int Fd) {
226   return _dup(Fd);
227 }
228 
229 void RemoveFile(const std::string &Path) {
230   _unlink(Path.c_str());
231 }
232 
233 void RenameFile(const std::string &OldPath, const std::string &NewPath) {
234   rename(OldPath.c_str(), NewPath.c_str());
235 }
236 
237 intptr_t GetHandleFromFd(int fd) {
238   return _get_osfhandle(fd);
239 }
240 
241 bool IsSeparator(char C) {
242   return C == '\\' || C == '/';
243 }
244 
245 // Parse disk designators, like "C:\". If Relative == true, also accepts: "C:".
246 // Returns number of characters considered if successful.
247 static size_t ParseDrive(const std::string &FileName, const size_t Offset,
248                          bool Relative = true) {
249   if (Offset + 1 >= FileName.size() || FileName[Offset + 1] != ':')
250     return 0;
251   if (Offset + 2 >= FileName.size() || !IsSeparator(FileName[Offset + 2])) {
252     if (!Relative) // Accept relative path?
253       return 0;
254     else
255       return 2;
256   }
257   return 3;
258 }
259 
260 // Parse a file name, like: SomeFile.txt
261 // Returns number of characters considered if successful.
262 static size_t ParseFileName(const std::string &FileName, const size_t Offset) {
263   size_t Pos = Offset;
264   const size_t End = FileName.size();
265   for(; Pos < End && !IsSeparator(FileName[Pos]); ++Pos)
266     ;
267   return Pos - Offset;
268 }
269 
270 // Parse a directory ending in separator, like: `SomeDir\`
271 // Returns number of characters considered if successful.
272 static size_t ParseDir(const std::string &FileName, const size_t Offset) {
273   size_t Pos = Offset;
274   const size_t End = FileName.size();
275   if (Pos >= End || IsSeparator(FileName[Pos]))
276     return 0;
277   for(; Pos < End && !IsSeparator(FileName[Pos]); ++Pos)
278     ;
279   if (Pos >= End)
280     return 0;
281   ++Pos; // Include separator.
282   return Pos - Offset;
283 }
284 
285 // Parse a servername and share, like: `SomeServer\SomeShare\`
286 // Returns number of characters considered if successful.
287 static size_t ParseServerAndShare(const std::string &FileName,
288                                   const size_t Offset) {
289   size_t Pos = Offset, Res;
290   if (!(Res = ParseDir(FileName, Pos)))
291     return 0;
292   Pos += Res;
293   if (!(Res = ParseDir(FileName, Pos)))
294     return 0;
295   Pos += Res;
296   return Pos - Offset;
297 }
298 
299 // Parse the given Ref string from the position Offset, to exactly match the
300 // given string Patt. Returns number of characters considered if successful.
301 static size_t ParseCustomString(const std::string &Ref, size_t Offset,
302                                 const char *Patt) {
303   size_t Len = strlen(Patt);
304   if (Offset + Len > Ref.size())
305     return 0;
306   return Ref.compare(Offset, Len, Patt) == 0 ? Len : 0;
307 }
308 
309 // Parse a location, like:
310 // \\?\UNC\Server\Share\  \\?\C:\  \\Server\Share\  \  C:\  C:
311 // Returns number of characters considered if successful.
312 static size_t ParseLocation(const std::string &FileName) {
313   size_t Pos = 0, Res;
314 
315   if ((Res = ParseCustomString(FileName, Pos, R"(\\?\)"))) {
316     Pos += Res;
317     if ((Res = ParseCustomString(FileName, Pos, R"(UNC\)"))) {
318       Pos += Res;
319       if ((Res = ParseServerAndShare(FileName, Pos)))
320         return Pos + Res;
321       return 0;
322     }
323     if ((Res = ParseDrive(FileName, Pos, false)))
324       return Pos + Res;
325     return 0;
326   }
327 
328   if (Pos < FileName.size() && IsSeparator(FileName[Pos])) {
329     ++Pos;
330     if (Pos < FileName.size() && IsSeparator(FileName[Pos])) {
331       ++Pos;
332       if ((Res = ParseServerAndShare(FileName, Pos)))
333         return Pos + Res;
334       return 0;
335     }
336     return Pos;
337   }
338 
339   if ((Res = ParseDrive(FileName, Pos)))
340     return Pos + Res;
341 
342   return Pos;
343 }
344 
345 std::string DirName(const std::string &FileName) {
346   size_t LocationLen = ParseLocation(FileName);
347   size_t DirLen = 0, Res;
348   while ((Res = ParseDir(FileName, LocationLen + DirLen)))
349     DirLen += Res;
350   size_t FileLen = ParseFileName(FileName, LocationLen + DirLen);
351 
352   if (LocationLen + DirLen + FileLen != FileName.size()) {
353     Printf("DirName() failed for \"%s\", invalid path.\n", FileName.c_str());
354     exit(1);
355   }
356 
357   if (DirLen) {
358     --DirLen; // Remove trailing separator.
359     if (!FileLen) { // Path ended in separator.
360       assert(DirLen);
361       // Remove file name from Dir.
362       while (DirLen && !IsSeparator(FileName[LocationLen + DirLen - 1]))
363         --DirLen;
364       if (DirLen) // Remove trailing separator.
365         --DirLen;
366     }
367   }
368 
369   if (!LocationLen) { // Relative path.
370     if (!DirLen)
371       return ".";
372     return std::string(".\\").append(FileName, 0, DirLen);
373   }
374 
375   return FileName.substr(0, LocationLen + DirLen);
376 }
377 
378 std::string TmpDir() {
379   std::string Tmp;
380   Tmp.resize(MAX_PATH + 1);
381   DWORD Size = GetTempPathA(Tmp.size(), &Tmp[0]);
382   if (Size == 0) {
383     Printf("Couldn't get Tmp path.\n");
384     exit(1);
385   }
386   Tmp.resize(Size);
387   return Tmp;
388 }
389 
390 bool IsInterestingCoverageFile(const std::string &FileName) {
391   if (FileName.find("Program Files") != std::string::npos)
392     return false;
393   if (FileName.find("compiler-rt\\lib\\") != std::string::npos)
394     return false; // sanitizer internal.
395   if (FileName == "<null>")
396     return false;
397   return true;
398 }
399 
400 void RawPrint(const char *Str) {
401   _write(2, Str, strlen(Str));
402 }
403 
404 void MkDir(const std::string &Path) {
405   if (CreateDirectoryA(Path.c_str(), nullptr)) return;
406   Printf("CreateDirectoryA failed for %s (Error code: %lu).\n", Path.c_str(),
407          GetLastError());
408 }
409 
410 void RmDir(const std::string &Path) {
411   if (RemoveDirectoryA(Path.c_str())) return;
412   Printf("RemoveDirectoryA failed for %s (Error code: %lu).\n", Path.c_str(),
413          GetLastError());
414 }
415 
416 const std::string &getDevNull() {
417   static const std::string devNull = "NUL";
418   return devNull;
419 }
420 
421 }  // namespace fuzzer
422 
423 #endif // LIBFUZZER_WINDOWS
424