chromium/third_party/unrar/src/secpassword.cpp

#include "rar.hpp"

#if defined(_WIN_ALL) && !defined(CHROMIUM_UNRAR)
typedef BOOL (WINAPI *CRYPTPROTECTMEMORY)(LPVOID pData,DWORD cbData,DWORD dwFlags);
typedef BOOL (WINAPI *CRYPTUNPROTECTMEMORY)(LPVOID pData,DWORD cbData,DWORD dwFlags);

#ifndef CRYPTPROTECTMEMORY_BLOCK_SIZE
#define CRYPTPROTECTMEMORY_BLOCK_SIZE …
#define CRYPTPROTECTMEMORY_SAME_PROCESS …
#define CRYPTPROTECTMEMORY_CROSS_PROCESS …
#endif

class CryptLoader
{
  private:
    HMODULE hCrypt;
    bool LoadCalled;
  public:
    CryptLoader() 
    {
      hCrypt=NULL;
      pCryptProtectMemory=NULL;
      pCryptUnprotectMemory=NULL;
      LoadCalled=false;
    }
    ~CryptLoader()
    {
      if (hCrypt!=NULL)
        FreeLibrary(hCrypt);
      hCrypt=NULL;
      pCryptProtectMemory=NULL;
      pCryptUnprotectMemory=NULL;
    };
    void Load()
    {
      if (!LoadCalled)
      {
        hCrypt = LoadSysLibrary(L"Crypt32.dll");
        if (hCrypt != NULL)
        {
          // Available since Vista.
          pCryptProtectMemory = (CRYPTPROTECTMEMORY)GetProcAddress(hCrypt, "CryptProtectMemory");
          pCryptUnprotectMemory = (CRYPTUNPROTECTMEMORY)GetProcAddress(hCrypt, "CryptUnprotectMemory");
        }
        LoadCalled=true;
      }
    }

    CRYPTPROTECTMEMORY pCryptProtectMemory;
    CRYPTUNPROTECTMEMORY pCryptUnprotectMemory;
};

// We need to call FreeLibrary when RAR is exiting.
static CryptLoader GlobalCryptLoader;
#endif

SecPassword::SecPassword()
{ … }


SecPassword::~SecPassword()
{ … }


void SecPassword::Clean()
{ … }
 

// When we call memset in end of function to clean local variables
// for security reason, compiler optimizer can remove such call.
// So we use our own function for this purpose.
void cleandata(void *data,size_t size)
{ … }


// We got a complain from user that it is possible to create WinRAR dump
// with "Create dump file" command in Windows Task Manager and then easily
// locate Unicode password string in the dump. It is unsecure if several
// people share the same computer and somebody left WinRAR copy with entered
// password. So we decided to obfuscate the password to make it more difficult
// to find it in dump.
void SecPassword::Process(const wchar *Src,size_t SrcSize,wchar *Dst,size_t DstSize,bool Encode)
{ … }


void SecPassword::Get(wchar *Psw,size_t MaxSize)
{ … }


void SecPassword::Get(std::wstring &Psw)
{ … }




void SecPassword::Set(const wchar *Psw)
{ … }


size_t SecPassword::Length()
{ … }


bool SecPassword::operator == (SecPassword &psw)
{ … }


// Set CrossProcess to true if we need to pass a password to another process.
// We use CrossProcess when transferring parameters to UAC elevated WinRAR
// and Windows GUI SFX modules.
void SecHideData(void *Data,size_t DataSize,bool Encode,bool CrossProcess)
{ … }