1 files changed, 124 insertions, 0 deletions
diff --git a/other-licenses/7zstub/src/CPP/7zip/Crypto/RandGen.cpp b/other-licenses/7zstub/src/CPP/7zip/Crypto/RandGen.cpp
new file mode 100644
index 0000000000..542f39bd56
--- /dev/null
+++ b/other-licenses/7zstub/src/CPP/7zip/Crypto/RandGen.cpp
@@ -0,0 +1,124 @@
+// RandGen.cpp
+
+#include "StdAfx.h"
+
+#ifndef _7ZIP_ST
+#include "../../Windows/Synchronization.h"
+#endif
+
+#include "RandGen.h"
+
+#ifndef _WIN32
+#include <unistd.h>
+#define USE_POSIX_TIME
+#define USE_POSIX_TIME2
+#endif
+
+#ifdef USE_POSIX_TIME
+#include <time.h>
+#ifdef USE_POSIX_TIME2
+#include <sys/time.h>
+#endif
+#endif
+
+// This is not very good random number generator.
+// Please use it only for salt.
+// First generated data block depends from timer and processID.
+// Other generated data blocks depend from previous state
+// Maybe it's possible to restore original timer value from generated value.
+
+#define HASH_UPD(x) Sha256_Update(&hash, (const Byte *)&x, sizeof(x));
+
+void CRandomGenerator::Init()
+{
+  CSha256 hash;
+  Sha256_Init(&hash);
+
+  #ifdef _WIN32
+  DWORD w = ::GetCurrentProcessId();
+  HASH_UPD(w);
+  w = ::GetCurrentThreadId();
+  HASH_UPD(w);
+  #else
+  pid_t pid = getpid();
+  HASH_UPD(pid);
+  pid = getppid();
+  HASH_UPD(pid);
+  #endif
+
+  for (unsigned i = 0; i <
+    #ifdef _DEBUG
+    2;
+    #else
+    1000;
+    #endif
+    i++)
+  {
+    #ifdef _WIN32
+    LARGE_INTEGER v;
+    if (::QueryPerformanceCounter(&v))
+      HASH_UPD(v.QuadPart);
+    #endif
+
+    #ifdef USE_POSIX_TIME
+    #ifdef USE_POSIX_TIME2
+    timeval v;
+    if (gettimeofday(&v, 0) == 0)
+    {
+      HASH_UPD(v.tv_sec);
+      HASH_UPD(v.tv_usec);
+    }
+    #endif
+    time_t v2 = time(NULL);
+    HASH_UPD(v2);
+    #endif
+
+    #ifdef _WIN32
+    DWORD tickCount = ::GetTickCount();
+    HASH_UPD(tickCount);
+    #endif
+    
+    for (unsigned j = 0; j < 100; j++)
+    {
+      Sha256_Final(&hash, _buff);
+      Sha256_Init(&hash);
+      Sha256_Update(&hash, _buff, SHA256_DIGEST_SIZE);
+    }
+  }
+  Sha256_Final(&hash, _buff);
+  _needInit = false;
+}
+
+#ifndef _7ZIP_ST
+  static NWindows::NSynchronization::CCriticalSection g_CriticalSection;
+  #define MT_LOCK NWindows::NSynchronization::CCriticalSectionLock lock(g_CriticalSection);
+#else
+  #define MT_LOCK
+#endif
+
+void CRandomGenerator::Generate(Byte *data, unsigned size)
+{
+  MT_LOCK
+
+  if (_needInit)
+    Init();
+  while (size != 0)
+  {
+    CSha256 hash;
+    
+    Sha256_Init(&hash);
+    Sha256_Update(&hash, _buff, SHA256_DIGEST_SIZE);
+    Sha256_Final(&hash, _buff);
+    
+    Sha256_Init(&hash);
+    UInt32 salt = 0xF672ABD1;
+    HASH_UPD(salt);
+    Sha256_Update(&hash, _buff, SHA256_DIGEST_SIZE);
+    Byte buff[SHA256_DIGEST_SIZE];
+    Sha256_Final(&hash, buff);
+    for (unsigned i = 0; i < SHA256_DIGEST_SIZE && size != 0; i++, size--)
+      *data++ = buff[i];
+  }
+}
+
+CRandomGenerator g_RandomGenerator;