🚀 go-pugleaf

Ok i seemed to have narrowed it down... using the below as my normal user
works fine but if i log off and logon as guest it fails to the
ShowMessage("Crypto Error #101");
so i am assuming its only admin rights allowed to create a new context...
any suggestions how to get out of this as i am going to be sending encrypted
files from one pc to another and need both to use the same methods for
decrypting..

   m_hProv = NULL;
    m_hKey  = NULL;

    // Get handle to the default key container in default CSP
   if (!CryptAcquireContext(&m_hProv,"container",MS_DEF_PROV,PROV_RSA_FULL,
                 0))
    if(!CryptAcquireContext(&m_hProv,"container",MS_DEF_PROV,PROV_RSA_FULL,
                 CRYPT_NEWKEYSET))

if(!CryptAcquireContext(&m_hProv,"container",MS_DEF_PROV,PROV_RSA_FULL,
                 CRYPT_MACHINE_KEYSET|CRYPT_NEWKEYSET))
              {
              ShowMessage("Crypto Error #101");
              return;
              }

thanks in advance..

"roger" <rogersmail@ntlworld.com> wrote in message
news:41ebbb0b@newsgroups.borland.com...
> Everything seemed fine using the below code to initialize the CSP and
being
> called with
> CMyCrypto myCrypto((LPSTR)thekey.c_str(), CALG_RC4);
>
> /////////////////////////////////////////////////////////
> CMyCrypto::CMyCrypto(LPTSTR pszPassword, ALG_ID algorithm)
> {
>     m_hProv = NULL;
>     m_hKey  = NULL;
>     // Get handle to the default key container in default CSP
>     if (CryptAcquireContext(&m_hProv,     // handle to CSP
>                             NULL,         // default container
>                             MS_DEF_PROV,  // default CSP
>                             PROV_RSA_FULL,// provider type
>                             0)) {         // action
> //// here i set CRYPT_NEWKEYSET ////
>
>         HCRYPTHASH hHash;
>
>         // Get handle to hash object
>         if (CryptCreateHash(m_hProv,   // handle to CSP
>                             CALG_MD5,  // hashing algorithm
>                             0,         // non-keyed hash
>                             0,         // reserved, must be zero
>                             &hHash)) { // hash object
>
>             // Hash the password
>             if (CryptHashData(hHash,   // handle to hash object
>                               (LPBYTE)pszPassword, // data buffer
>                               lstrlen(pszPassword)*sizeof(TCHAR),
>                               0)) {    // flags
>
>                 // Create the session key using the hashed password
>                 CryptDeriveKey(m_hProv,   // handle to CSP
>                                algorithm, // encryption algorithm
>                                hHash,     // hashed data
>                                CRYPT_EXPORTABLE | 0x00280000,
>                                &m_hKey);  // session key
>             }
>             CryptDestroyHash(hHash);
>         }
>     }
> }
> /////////////////////////////////////////////////////////////
>
> However when i tried the same program on a newly installed version of XP
the
> CryptAcquireContext() return false.
> I tried with the action set as CRYPT_NEWKEYSET rather than 0 and then
> retried with it set to 0 again and it worked..
> so i am under the impression that if the function fails then recall with
> CRYPT_NEWKEYSET and then start over.. as just carrying on after using
> CRYPT_NEWKEYSET did not work.
> My main concern however that is if i do it this way is that one pc will be
> sending crypted commands and files to another..will they choose different
> providers and even though they both use the same keystr for dec/encryption
> hows it going to decrypt correctly when using different providers or do i
> have to make sure it uses CRYPT_NEWKEYSET to use the same provider...sorry
> for the lack of knowledge here but its my virgin run at it..
>
>
>
> "Remy Lebeau (TeamB)" <no.spam@no.spam.com> wrote in message
> news:41a385b5$1@newsgroups.borland.com...
> >
> > "roger" <rogersmail@ntlworld.com> wrote in message
> > news:41a37ce2$1@newsgroups.borland.com...
> >
> >
> > >     dwDataLen = stringsin->Strings[a].Length();
> > >     dwEncLen = dwDataLen;
> > >     dwDataLen = stringsin->Strings[a].Length();
> >
> > The second assignment to dwDataLen is redundant.  It already has the
value
> > of Length().
> >
> > >     szData = new CHAR[dwEncLen + 1];
> >
> > You are allocating a buffer...
> >
> > >      szData = NULL;
> >
> > Yet you are then nullifying the pointer withoug actually freeing it.
> >
> > >      delete[] szData;
> >
> > szData is NULL by this point.
> >
> > >     if (bEncrypt) {
> > >         if (myCrypto.Encrypt((BYTE*)szData,&dwDataLen,dwDataLen,true))
> > >                  stringsout->Add(StrPas(szData));
> > >       } else {
> > >         if (myCrypto.Decrypt((BYTE*)szData,&dwDataLen, true))
> > >                 stringsout->Add(StrPas(szData));
> > >              }
> >
> > You don't need to use StrPas().  It is an obsolete function.  Just pass
> the
> > char* pointer directly, it will be converted to AnsiString automatically
> for
> > you:
> >
> >     stringsout->Add(szData);
> >
> > Also, for your encryption, what does the actual encrypted data look
like?
> > Are there are '\0' characters in it?  There most likely is.  That would
> > account for the incomplete data being passed back to the TStringList,
> since
> > you are not taking '\0' characters into account at all.
> >
> > Try this code instead (untested):
> >
> >     void __fastcall TForm1::CryptStringList(TStrings* stringsin,
TStrings*
> > stringsout, const AnsiString &thekey)
> >     {
> >         DWORD dwDataLen, dwEncLen;
> >         AnsiString asData;
> >         bool bOk;
> >         CMyCrypto myCrypto(thekey.c_str(), CALG_RC4);
> >
> >         stringsout->BeginUpdate();
> >         try
> >         {
> >             for(int a = 0; a < stringsin->Count; ++a)
> >             {
> >                 dwDataLen = stringsin->Strings[a].Length();
> >                 dwEncLen = dwDataLen;
> >
> >                 bOk = !bEncrypt;
> >                 if( !bOk )
> >                     bOk = myCrypto.Encrypt(NULL, &dwEncLen, 0, true);
> >
> >                 if( bOk )
> >                 {
> >                     if( dwEncLen < dwDataLen )
> >                         asData.SetLength(dwDataLen);
> >                     else
> >                         asData.SetLength(dwEncLen);
> >
> >                     strncpy(asData.c_str(),
stringsin->Strings[a].c_str(),
> > dwDataLen);
> >
> >                     if( bEncrypt )
> >                         bOk = myCrypto.Encrypt((BYTE*)szData.c_str(),
> > &dwDataLen, asData.Length(), true);
> >                     else
> >                         bOk = myCrypto.Decrypt((BYTE*)szData.c_str(),
> > &dwDataLen, true);
> >
> >                     if( bOk )
> >                     {
> >                         asData.SetLength(dwDataLen);
> >                         stringsout->Add(asData);
> >                     }
> >                 }
> >             }
> >         }
> >         __finally {
> >             stringsout->EndUpdate();
> >         }
> >     }
> >
> >
> > Gambit
> >
> >
>
>