CryptUnprotectData append LMEM to plain string

collapsed (10)
hi,
i'm using CryptUnprotectData to decrypt a value in a sqlite3's column crypted with CryptProtectData.
The decryption works,but when i display the string the program show plain string + random char + "LMEM"

the function is :

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std::vector<std::string> Decrypt(sqlite3_stmt * stmt,int column)
 {
	 LPWSTR str = NULL;
	 
	 std::vector<std::string> data;
	 std::string tmp;

	 DATA_BLOB in,out;
	 memset(&in,0,sizeof(in));
	 memset(&out,0,sizeof(out));
	 
	 try
	 {
		 while(sqlite3_step(stmt) == SQLITE_ROW)
		 {

			 in.cbData = sqlite3_column_bytes(stmt,column);
			 in.pbData = (BYTE *)sqlite3_column_blob(stmt,column);

			 if(!CryptUnprotectData(&in,&str,NULL,NULL,NULL,0,&out))
			 {
				 throw chrome::Event::Err(GetLastError());
			 }

			 tmp = reinterpret_cast<char*>(out.pbData);
			 data.push_back(tmp);



			 std::cout << ".";
		 }

		 return data;
	 }
	 catch(chrome::Event::Err& exc)
	 {
		 std::cerr << "CryptUnprotectData() fail " << GetLastError() << std::endl;
		 LocalFree(str);
		 LocalFree(&in);
		 LocalFree(&out);
		 data.at(0) = "ERROR";
		 return data;
	 }


 }


Thanks to who'll answer
modoran (1988)
collapsed (10)
I've seen the example ,but it doesn't answer my question...
collapsed (10)
none can help?
coder777 (4153)
The reason is that on line 25 out.pbData does not have a terminating 0. You need out.cbData in order to determine the correct string length
collapsed (10)
How can i null-terminate a byte* string with the STL?
Last edited on
coder777 (4153)
like so:

tmp.assign(reinterpret_cast<char*>(out.pbData), out.cbData);
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