1 /*
2  *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #include "webrtc/base/win32.h"
12 
13 #include <winsock2.h>
14 #include <ws2tcpip.h>
15 #include <algorithm>
16 
17 #include "webrtc/base/arraysize.h"
18 #include "webrtc/base/basictypes.h"
19 #include "webrtc/base/byteorder.h"
20 #include "webrtc/base/common.h"
21 #include "webrtc/base/logging.h"
22 
23 namespace rtc {
24 
25 // Helper function declarations for inet_ntop/inet_pton.
26 static const char* inet_ntop_v4(const void* src, char* dst, socklen_t size);
27 static const char* inet_ntop_v6(const void* src, char* dst, socklen_t size);
28 static int inet_pton_v4(const char* src, void* dst);
29 static int inet_pton_v6(const char* src, void* dst);
30 
31 // Implementation of inet_ntop (create a printable representation of an
32 // ip address). XP doesn't have its own inet_ntop, and
33 // WSAAddressToString requires both IPv6 to be  installed and for Winsock
34 // to be initialized.
win32_inet_ntop(int af,const void * src,char * dst,socklen_t size)35 const char* win32_inet_ntop(int af, const void *src,
36                             char* dst, socklen_t size) {
37   if (!src || !dst) {
38     return NULL;
39   }
40   switch (af) {
41     case AF_INET: {
42       return inet_ntop_v4(src, dst, size);
43     }
44     case AF_INET6: {
45       return inet_ntop_v6(src, dst, size);
46     }
47   }
48   return NULL;
49 }
50 
51 // As above, but for inet_pton. Implements inet_pton for v4 and v6.
52 // Note that our inet_ntop will output normal 'dotted' v4 addresses only.
win32_inet_pton(int af,const char * src,void * dst)53 int win32_inet_pton(int af, const char* src, void* dst) {
54   if (!src || !dst) {
55     return 0;
56   }
57   if (af == AF_INET) {
58     return inet_pton_v4(src, dst);
59   } else if (af == AF_INET6) {
60     return inet_pton_v6(src, dst);
61   }
62   return -1;
63 }
64 
65 // Helper function for inet_ntop for IPv4 addresses.
66 // Outputs "dotted-quad" decimal notation.
inet_ntop_v4(const void * src,char * dst,socklen_t size)67 const char* inet_ntop_v4(const void* src, char* dst, socklen_t size) {
68   if (size < INET_ADDRSTRLEN) {
69     return NULL;
70   }
71   const struct in_addr* as_in_addr =
72       reinterpret_cast<const struct in_addr*>(src);
73   rtc::sprintfn(dst, size, "%d.%d.%d.%d",
74                       as_in_addr->S_un.S_un_b.s_b1,
75                       as_in_addr->S_un.S_un_b.s_b2,
76                       as_in_addr->S_un.S_un_b.s_b3,
77                       as_in_addr->S_un.S_un_b.s_b4);
78   return dst;
79 }
80 
81 // Helper function for inet_ntop for IPv6 addresses.
inet_ntop_v6(const void * src,char * dst,socklen_t size)82 const char* inet_ntop_v6(const void* src, char* dst, socklen_t size) {
83   if (size < INET6_ADDRSTRLEN) {
84     return NULL;
85   }
86   const uint16_t* as_shorts = reinterpret_cast<const uint16_t*>(src);
87   int runpos[8];
88   int current = 1;
89   int max = 0;
90   int maxpos = -1;
91   int run_array_size = arraysize(runpos);
92   // Run over the address marking runs of 0s.
93   for (int i = 0; i < run_array_size; ++i) {
94     if (as_shorts[i] == 0) {
95       runpos[i] = current;
96       if (current > max) {
97         maxpos = i;
98         max = current;
99       }
100       ++current;
101     } else {
102       runpos[i] = -1;
103       current = 1;
104     }
105   }
106 
107   if (max > 0) {
108     int tmpmax = maxpos;
109     // Run back through, setting -1 for all but the longest run.
110     for (int i = run_array_size - 1; i >= 0; i--) {
111       if (i > tmpmax) {
112         runpos[i] = -1;
113       } else if (runpos[i] == -1) {
114         // We're less than maxpos, we hit a -1, so the 'good' run is done.
115         // Setting tmpmax -1 means all remaining positions get set to -1.
116         tmpmax = -1;
117       }
118     }
119   }
120 
121   char* cursor = dst;
122   // Print IPv4 compatible and IPv4 mapped addresses using the IPv4 helper.
123   // These addresses have an initial run of either eight zero-bytes followed
124   // by 0xFFFF, or an initial run of ten zero-bytes.
125   if (runpos[0] == 1 && (maxpos == 5 ||
126                          (maxpos == 4 && as_shorts[5] == 0xFFFF))) {
127     *cursor++ = ':';
128     *cursor++ = ':';
129     if (maxpos == 4) {
130       cursor += rtc::sprintfn(cursor, INET6_ADDRSTRLEN - 2, "ffff:");
131     }
132     const struct in_addr* as_v4 =
133         reinterpret_cast<const struct in_addr*>(&(as_shorts[6]));
134     inet_ntop_v4(as_v4, cursor,
135                  static_cast<socklen_t>(INET6_ADDRSTRLEN - (cursor - dst)));
136   } else {
137     for (int i = 0; i < run_array_size; ++i) {
138       if (runpos[i] == -1) {
139         cursor += rtc::sprintfn(cursor,
140                                       INET6_ADDRSTRLEN - (cursor - dst),
141                                       "%x", NetworkToHost16(as_shorts[i]));
142         if (i != 7 && runpos[i + 1] != 1) {
143           *cursor++ = ':';
144         }
145       } else if (runpos[i] == 1) {
146         // Entered the run; print the colons and skip the run.
147         *cursor++ = ':';
148         *cursor++ = ':';
149         i += (max - 1);
150       }
151     }
152   }
153   return dst;
154 }
155 
156 // Helper function for inet_pton for IPv4 addresses.
157 // |src| points to a character string containing an IPv4 network address in
158 // dotted-decimal format, "ddd.ddd.ddd.ddd", where ddd is a decimal number
159 // of up to three digits in the range 0 to 255.
160 // The address is converted and copied to dst,
161 // which must be sizeof(struct in_addr) (4) bytes (32 bits) long.
inet_pton_v4(const char * src,void * dst)162 int inet_pton_v4(const char* src, void* dst) {
163   const int kIpv4AddressSize = 4;
164   int found = 0;
165   const char* src_pos = src;
166   unsigned char result[kIpv4AddressSize] = {0};
167 
168   while (*src_pos != '\0') {
169     // strtol won't treat whitespace characters in the begining as an error,
170     // so check to ensure this is started with digit before passing to strtol.
171     if (!isdigit(*src_pos)) {
172       return 0;
173     }
174     char* end_pos;
175     long value = strtol(src_pos, &end_pos, 10);
176     if (value < 0 || value > 255 || src_pos == end_pos) {
177       return 0;
178     }
179     ++found;
180     if (found > kIpv4AddressSize) {
181       return 0;
182     }
183     result[found - 1] = static_cast<unsigned char>(value);
184     src_pos = end_pos;
185     if (*src_pos == '.') {
186       // There's more.
187       ++src_pos;
188     } else if (*src_pos != '\0') {
189       // If it's neither '.' nor '\0' then return fail.
190       return 0;
191     }
192   }
193   if (found != kIpv4AddressSize) {
194     return 0;
195   }
196   memcpy(dst, result, sizeof(result));
197   return 1;
198 }
199 
200 // Helper function for inet_pton for IPv6 addresses.
inet_pton_v6(const char * src,void * dst)201 int inet_pton_v6(const char* src, void* dst) {
202   // sscanf will pick any other invalid chars up, but it parses 0xnnnn as hex.
203   // Check for literal x in the input string.
204   const char* readcursor = src;
205   char c = *readcursor++;
206   while (c) {
207     if (c == 'x') {
208       return 0;
209     }
210     c = *readcursor++;
211   }
212   readcursor = src;
213 
214   struct in6_addr an_addr;
215   memset(&an_addr, 0, sizeof(an_addr));
216 
217   uint16_t* addr_cursor = reinterpret_cast<uint16_t*>(&an_addr.s6_addr[0]);
218   uint16_t* addr_end = reinterpret_cast<uint16_t*>(&an_addr.s6_addr[16]);
219   bool seencompressed = false;
220 
221   // Addresses that start with "::" (i.e., a run of initial zeros) or
222   // "::ffff:" can potentially be IPv4 mapped or compatibility addresses.
223   // These have dotted-style IPv4 addresses on the end (e.g. "::192.168.7.1").
224   if (*readcursor == ':' && *(readcursor+1) == ':' &&
225       *(readcursor + 2) != 0) {
226     // Check for periods, which we'll take as a sign of v4 addresses.
227     const char* addrstart = readcursor + 2;
228     if (rtc::strchr(addrstart, ".")) {
229       const char* colon = rtc::strchr(addrstart, "::");
230       if (colon) {
231         uint16_t a_short;
232         int bytesread = 0;
233         if (sscanf(addrstart, "%hx%n", &a_short, &bytesread) != 1 ||
234             a_short != 0xFFFF || bytesread != 4) {
235           // Colons + periods means has to be ::ffff:a.b.c.d. But it wasn't.
236           return 0;
237         } else {
238           an_addr.s6_addr[10] = 0xFF;
239           an_addr.s6_addr[11] = 0xFF;
240           addrstart = colon + 1;
241         }
242       }
243       struct in_addr v4;
244       if (inet_pton_v4(addrstart, &v4.s_addr)) {
245         memcpy(&an_addr.s6_addr[12], &v4, sizeof(v4));
246         memcpy(dst, &an_addr, sizeof(an_addr));
247         return 1;
248       } else {
249         // Invalid v4 address.
250         return 0;
251       }
252     }
253   }
254 
255   // For addresses without a trailing IPv4 component ('normal' IPv6 addresses).
256   while (*readcursor != 0 && addr_cursor < addr_end) {
257     if (*readcursor == ':') {
258       if (*(readcursor + 1) == ':') {
259         if (seencompressed) {
260           // Can only have one compressed run of zeroes ("::") per address.
261           return 0;
262         }
263         // Hit a compressed run. Count colons to figure out how much of the
264         // address is skipped.
265         readcursor += 2;
266         const char* coloncounter = readcursor;
267         int coloncount = 0;
268         if (*coloncounter == 0) {
269           // Special case - trailing ::.
270           addr_cursor = addr_end;
271         } else {
272           while (*coloncounter) {
273             if (*coloncounter == ':') {
274               ++coloncount;
275             }
276             ++coloncounter;
277           }
278           // (coloncount + 1) is the number of shorts left in the address.
279           addr_cursor = addr_end - (coloncount + 1);
280           seencompressed = true;
281         }
282       } else {
283         ++readcursor;
284       }
285     } else {
286       uint16_t word;
287       int bytesread = 0;
288       if (sscanf(readcursor, "%hx%n", &word, &bytesread) != 1) {
289         return 0;
290       } else {
291         *addr_cursor = HostToNetwork16(word);
292         ++addr_cursor;
293         readcursor += bytesread;
294         if (*readcursor != ':' && *readcursor != '\0') {
295           return 0;
296         }
297       }
298     }
299   }
300 
301   if (*readcursor != '\0' || addr_cursor < addr_end) {
302     // Catches addresses too short or too long.
303     return 0;
304   }
305   memcpy(dst, &an_addr, sizeof(an_addr));
306   return 1;
307 }
308 
309 //
310 // Unix time is in seconds relative to 1/1/1970.  So we compute the windows
311 // FILETIME of that time/date, then we add/subtract in appropriate units to
312 // convert to/from unix time.
313 // The units of FILETIME are 100ns intervals, so by multiplying by or dividing
314 // by 10000000, we can convert to/from seconds.
315 //
316 // FileTime = UnixTime*10000000 + FileTime(1970)
317 // UnixTime = (FileTime-FileTime(1970))/10000000
318 //
319 
FileTimeToUnixTime(const FILETIME & ft,time_t * ut)320 void FileTimeToUnixTime(const FILETIME& ft, time_t* ut) {
321   ASSERT(NULL != ut);
322 
323   // FILETIME has an earlier date base than time_t (1/1/1970), so subtract off
324   // the difference.
325   SYSTEMTIME base_st;
326   memset(&base_st, 0, sizeof(base_st));
327   base_st.wDay = 1;
328   base_st.wMonth = 1;
329   base_st.wYear = 1970;
330 
331   FILETIME base_ft;
332   SystemTimeToFileTime(&base_st, &base_ft);
333 
334   ULARGE_INTEGER base_ul, current_ul;
335   memcpy(&base_ul, &base_ft, sizeof(FILETIME));
336   memcpy(&current_ul, &ft, sizeof(FILETIME));
337 
338   // Divide by big number to convert to seconds, then subtract out the 1970
339   // base date value.
340   const ULONGLONG RATIO = 10000000;
341   *ut = static_cast<time_t>((current_ul.QuadPart - base_ul.QuadPart) / RATIO);
342 }
343 
UnixTimeToFileTime(const time_t & ut,FILETIME * ft)344 void UnixTimeToFileTime(const time_t& ut, FILETIME* ft) {
345   ASSERT(NULL != ft);
346 
347   // FILETIME has an earlier date base than time_t (1/1/1970), so add in
348   // the difference.
349   SYSTEMTIME base_st;
350   memset(&base_st, 0, sizeof(base_st));
351   base_st.wDay = 1;
352   base_st.wMonth = 1;
353   base_st.wYear = 1970;
354 
355   FILETIME base_ft;
356   SystemTimeToFileTime(&base_st, &base_ft);
357 
358   ULARGE_INTEGER base_ul;
359   memcpy(&base_ul, &base_ft, sizeof(FILETIME));
360 
361   // Multiply by big number to convert to 100ns units, then add in the 1970
362   // base date value.
363   const ULONGLONG RATIO = 10000000;
364   ULARGE_INTEGER current_ul;
365   current_ul.QuadPart = base_ul.QuadPart + static_cast<int64_t>(ut) * RATIO;
366   memcpy(ft, &current_ul, sizeof(FILETIME));
367 }
368 
Utf8ToWindowsFilename(const std::string & utf8,std::wstring * filename)369 bool Utf8ToWindowsFilename(const std::string& utf8, std::wstring* filename) {
370   // TODO: Integrate into fileutils.h
371   // TODO: Handle wide and non-wide cases via TCHAR?
372   // TODO: Skip \\?\ processing if the length is not > MAX_PATH?
373   // TODO: Write unittests
374 
375   // Convert to Utf16
376   int wlen = ::MultiByteToWideChar(CP_UTF8, 0, utf8.c_str(),
377                                    static_cast<int>(utf8.length() + 1), NULL,
378                                    0);
379   if (0 == wlen) {
380     return false;
381   }
382   wchar_t* wfilename = STACK_ARRAY(wchar_t, wlen);
383   if (0 == ::MultiByteToWideChar(CP_UTF8, 0, utf8.c_str(),
384                                  static_cast<int>(utf8.length() + 1),
385                                  wfilename, wlen)) {
386     return false;
387   }
388   // Replace forward slashes with backslashes
389   std::replace(wfilename, wfilename + wlen, L'/', L'\\');
390   // Convert to complete filename
391   DWORD full_len = ::GetFullPathName(wfilename, 0, NULL, NULL);
392   if (0 == full_len) {
393     return false;
394   }
395   wchar_t* filepart = NULL;
396   wchar_t* full_filename = STACK_ARRAY(wchar_t, full_len + 6);
397   wchar_t* start = full_filename + 6;
398   if (0 == ::GetFullPathName(wfilename, full_len, start, &filepart)) {
399     return false;
400   }
401   // Add long-path prefix
402   const wchar_t kLongPathPrefix[] = L"\\\\?\\UNC";
403   if ((start[0] != L'\\') || (start[1] != L'\\')) {
404     // Non-unc path:     <pathname>
405     //      Becomes: \\?\<pathname>
406     start -= 4;
407     ASSERT(start >= full_filename);
408     memcpy(start, kLongPathPrefix, 4 * sizeof(wchar_t));
409   } else if (start[2] != L'?') {
410     // Unc path:       \\<server>\<pathname>
411     //  Becomes: \\?\UNC\<server>\<pathname>
412     start -= 6;
413     ASSERT(start >= full_filename);
414     memcpy(start, kLongPathPrefix, 7 * sizeof(wchar_t));
415   } else {
416     // Already in long-path form.
417   }
418   filename->assign(start);
419   return true;
420 }
421 
GetOsVersion(int * major,int * minor,int * build)422 bool GetOsVersion(int* major, int* minor, int* build) {
423   OSVERSIONINFO info = {0};
424   info.dwOSVersionInfoSize = sizeof(info);
425   if (GetVersionEx(&info)) {
426     if (major) *major = info.dwMajorVersion;
427     if (minor) *minor = info.dwMinorVersion;
428     if (build) *build = info.dwBuildNumber;
429     return true;
430   }
431   return false;
432 }
433 
GetCurrentProcessIntegrityLevel(int * level)434 bool GetCurrentProcessIntegrityLevel(int* level) {
435   bool ret = false;
436   HANDLE process = ::GetCurrentProcess(), token;
437   if (OpenProcessToken(process, TOKEN_QUERY | TOKEN_QUERY_SOURCE, &token)) {
438     DWORD size;
439     if (!GetTokenInformation(token, TokenIntegrityLevel, NULL, 0, &size) &&
440         GetLastError() == ERROR_INSUFFICIENT_BUFFER) {
441 
442       char* buf = STACK_ARRAY(char, size);
443       TOKEN_MANDATORY_LABEL* til =
444           reinterpret_cast<TOKEN_MANDATORY_LABEL*>(buf);
445       if (GetTokenInformation(token, TokenIntegrityLevel, til, size, &size)) {
446 
447         DWORD count = *GetSidSubAuthorityCount(til->Label.Sid);
448         *level = *GetSidSubAuthority(til->Label.Sid, count - 1);
449         ret = true;
450       }
451     }
452     CloseHandle(token);
453   }
454   return ret;
455 }
456 
457 }  // namespace rtc
458