Update NSS to NSS_3_16_RC0.

nss/lib/freebl/win_rand.c

 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "secrng.h"
-#include "secerr.h"
 
 #ifdef XP_WIN
 #include <windows.h>
-#include <shlobj.h>     /* for CSIDL constants */
 #include <time.h>
-#include <io.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <stdio.h>
-#include "prio.h"
-#include "prerror.h"
-
-static PRInt32  filesToRead;
-static DWORD    totalFileBytes;
-static DWORD    maxFileBytes    = 250000;       /* 250 thousand */
-static DWORD    dwNumFiles, dwReadEvery, dwFileToRead;
-static PRBool   usedWindowsPRNG;
 
 static BOOL
 CurrentClockTickTime(LPDWORD lpdwHigh, LPDWORD lpdwLow)
 {
     LARGE_INTEGER   liCount;
 
     if (!QueryPerformanceCounter(&liCount))
         return FALSE;
 
     *lpdwHigh = liCount.u.HighPart;
@@ skipping 43 matching lines @@
 
     // get the time in seconds since midnight Jan 1, 1970
     time(&sTime);
     nBytes = sizeof(sTime) > maxbuf ? maxbuf : sizeof(sTime);
     memcpy(((char *)buf) + n, &sTime, nBytes);
     n += nBytes;
 
     return n;
 }
 
-typedef PRInt32 (* Handler)(const PRUnichar *);
-#define MAX_DEPTH 2
-#define MAX_FOLDERS 4
-#define MAX_FILES 1024
-
-static void
-EnumSystemFilesInFolder(Handler func, PRUnichar* szSysDir, int maxDepth) 
-{
-    int                 iContinue;
-    unsigned int        uFolders  = 0;
-    unsigned int        uFiles    = 0;
-    HANDLE              lFindHandle;
-    WIN32_FIND_DATAW    fdData;
-    PRUnichar           szFileName[_MAX_PATH];
-
-    if (maxDepth < 0)
-        return;
-    // append *.* so we actually look for files.
-    _snwprintf(szFileName, _MAX_PATH, L"%s\\*.*", szSysDir);
-    szFileName[_MAX_PATH - 1] = L'\0';
-
-    lFindHandle = FindFirstFileW(szFileName, &fdData);
-    if (lFindHandle == INVALID_HANDLE_VALUE)
-        return;
-    do {
-        iContinue = 1;
-        if (wcscmp(fdData.cFileName, L".") == 0 ||
-            wcscmp(fdData.cFileName, L"..") == 0) {
-            // skip "." and ".."
-        } else {
-            // pass the full pathname to the callback
-            _snwprintf(szFileName, _MAX_PATH, L"%s\\%s", szSysDir, 
-                       fdData.cFileName);
-            szFileName[_MAX_PATH - 1] = L'\0';
-            if (fdData.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) {
-                if (++uFolders <= MAX_FOLDERS)
-                    EnumSystemFilesInFolder(func, szFileName, maxDepth - 1);
-            } else {
-                iContinue = (++uFiles <= MAX_FILES) && !(*func)(szFileName);
-            }
-        }
-        if (iContinue)
-            iContinue = FindNextFileW(lFindHandle, &fdData);
-    } while (iContinue);
-    FindClose(lFindHandle);
-}
-
-static BOOL
-EnumSystemFiles(Handler func)
-{
-    PRUnichar szSysDir[_MAX_PATH];
-    static const int folders[] = {
-        CSIDL_BITBUCKET,  
-        CSIDL_RECENT,
-        CSIDL_INTERNET_CACHE, 
-        CSIDL_HISTORY,
-        0
-    };
-    int i = 0;
-    if (_MAX_PATH > (i = GetTempPathW(_MAX_PATH, szSysDir))) {
-        if (i > 0 && szSysDir[i-1] == L'\\')
-            szSysDir[i-1] = L'\0'; // we need to lop off the trailing slash
-        EnumSystemFilesInFolder(func, szSysDir, MAX_DEPTH);
-    }
-    for(i = 0; folders[i]; i++) {
-        DWORD rv = SHGetSpecialFolderPathW(NULL, szSysDir, folders[i], 0);
-        if (szSysDir[0])
-            EnumSystemFilesInFolder(func, szSysDir, MAX_DEPTH);
-        szSysDir[0] =  L'\0';
-    }
-    return PR_TRUE;
-}
-
-static PRInt32
-CountFiles(const PRUnichar *file)
-{
-    dwNumFiles++;
-    return 0;
-}
-
-static int
-ReadSingleFile(const char *filename)
-{
-    PRFileDesc *    file;
-    unsigned char   buffer[1024];
-
-    file = PR_Open(filename, PR_RDONLY, 0);
-    if (file != NULL) {
-        while (PR_Read(file, buffer, sizeof buffer) > 0)
-            ;
-        PR_Close(file);
-    }
-    return (file != NULL);
-}
-
-static PRInt32
-ReadOneFile(const PRUnichar *szFileName)
-{
-    char narrowFileName[_MAX_PATH];
-
-    if (dwNumFiles == dwFileToRead) {
-        int success = WideCharToMultiByte(CP_ACP, 0, szFileName, -1, 
-                                          narrowFileName, _MAX_PATH, 
-                                          NULL, NULL);
-        if (success)
-            success = ReadSingleFile(narrowFileName);
-        if (!success)
-            dwFileToRead++; /* couldn't read this one, read the next one. */
-    }
-    dwNumFiles++;
-    return dwNumFiles > dwFileToRead;
-}
-
-static PRInt32
-ReadFiles(const PRUnichar *szFileName)
-{
-    char narrowFileName[_MAX_PATH];
-
-    if ((dwNumFiles % dwReadEvery) == 0) {
-        ++filesToRead;
-    }
-    if (filesToRead) {
-        DWORD prevFileBytes = totalFileBytes;
-        int   iContinue     = WideCharToMultiByte(CP_ACP, 0, szFileName, -1, 
-                                                  narrowFileName, _MAX_PATH, 
-                                                  NULL, NULL);
-        if (iContinue) {
-            RNG_FileForRNG(narrowFileName);
-        }
-        if (prevFileBytes < totalFileBytes) {
-            --filesToRead;
-        }
-    }
-    dwNumFiles++;
-    return (totalFileBytes >= maxFileBytes);
-}
-
-static void
-ReadSystemFiles(void)
-{
-    // first count the number of files
-    dwNumFiles = 0;
-    if (!EnumSystemFiles(CountFiles))
-        return;
-
-    RNG_RandomUpdate(&dwNumFiles, sizeof(dwNumFiles));
-
-    // now read the first 10 readable files, then 10 or 11 files
-    // spread throughout the system directory
-    filesToRead = 10;
-    if (dwNumFiles == 0)
-        return;
-
-    dwReadEvery = dwNumFiles / 10;
-    if (dwReadEvery == 0)
-        dwReadEvery = 1;  // less than 10 files
-
-    dwNumFiles = 0;
-    totalFileBytes = 0;
-    EnumSystemFiles(ReadFiles);
-}
-
 void RNG_SystemInfoForRNG(void)
 {
     DWORD           dwVal;
     char            buffer[256];
     int             nBytes;
     MEMORYSTATUS    sMem;
     HANDLE          hVal;
     DWORD           dwSerialNum;
     DWORD           dwComponentLen;
     DWORD           dwSysFlags;
@@ skipping 42 matching lines @@
     RNG_RandomUpdate(buffer,          strlen(buffer));
 
     if (GetDiskFreeSpace(NULL, &dwSectors, &dwBytes, &dwFreeClusters, 
                          &dwNumClusters)) {
         RNG_RandomUpdate(&dwSectors,      sizeof(dwSectors));
         RNG_RandomUpdate(&dwBytes,        sizeof(dwBytes));
         RNG_RandomUpdate(&dwFreeClusters, sizeof(dwFreeClusters));
         RNG_RandomUpdate(&dwNumClusters,  sizeof(dwNumClusters));
     }
 
-    // Skip the potentially slow file scanning if the OS's PRNG worked.
-    if (!usedWindowsPRNG)
-        ReadSystemFiles();
-
-    nBytes = RNG_GetNoise(buffer, 20);  // get up to 20 bytes
-    RNG_RandomUpdate(buffer, nBytes);
-}
-
-static void rng_systemJitter(void)
-{   
-    dwNumFiles = 0;
-    EnumSystemFiles(ReadOneFile);
-    dwFileToRead++;
-    if (dwFileToRead >= dwNumFiles) {
-        dwFileToRead = 0;
-    }
-}
-
-
-void RNG_FileForRNG(const char *filename)
-{
-    FILE*           file;
-    int             nBytes;
-    struct stat     stat_buf;
-    unsigned char   buffer[1024];
-
-    /* windows doesn't initialize all the bytes in the stat buf,
-     * so initialize them all here to avoid UMRs.
-     */
-    memset(&stat_buf, 0, sizeof stat_buf);
-
-    if (stat((char *)filename, &stat_buf) < 0)
-        return;
-
-    RNG_RandomUpdate((unsigned char*)&stat_buf, sizeof(stat_buf));
-
-    file = fopen((char *)filename, "r");
-    if (file != NULL) {
-        for (;;) {
-            size_t  bytes = fread(buffer, 1, sizeof(buffer), file);
-
-            if (bytes == 0)
-                break;
-
-            RNG_RandomUpdate(buffer, bytes);
-            totalFileBytes += bytes;
-            if (totalFileBytes > maxFileBytes)
-                break;
-        }
-
-        fclose(file);
-    }
-
     nBytes = RNG_GetNoise(buffer, 20);  // get up to 20 bytes
     RNG_RandomUpdate(buffer, nBytes);
 }
 
 
 /*
- * Windows XP and Windows Server 2003 and later have RtlGenRandom,
- * which must be looked up by the name SystemFunction036.
+ * The RtlGenRandom function is declared in <ntsecapi.h>, but the
+ * declaration is missing a calling convention specifier. So we
+ * declare it manually here.
  */
-typedef BOOLEAN
-(APIENTRY *RtlGenRandomFn)(
+#define RtlGenRandom SystemFunction036
+DECLSPEC_IMPORT BOOLEAN WINAPI RtlGenRandom(
     PVOID RandomBuffer,
     ULONG RandomBufferLength);
 
 size_t RNG_SystemRNG(void *dest, size_t maxLen)
 {
-    HMODULE hModule;
-    RtlGenRandomFn pRtlGenRandom;
     size_t bytes = 0;
 
-    usedWindowsPRNG = PR_FALSE;
-    hModule = LoadLibrary("advapi32.dll");
-    if (hModule == NULL) {
-        return bytes;
+    if (RtlGenRandom(dest, maxLen)) {
+        bytes = maxLen;
     }
-    pRtlGenRandom = (RtlGenRandomFn)
-        GetProcAddress(hModule, "SystemFunction036");
-    if (pRtlGenRandom && pRtlGenRandom(dest, maxLen)) {
-        bytes = maxLen;
-        usedWindowsPRNG = PR_TRUE;
-    }
-    FreeLibrary(hModule);
     return bytes;
 }
 #endif  /* is XP_WIN */