isepwchk/pwchk/sncheck.c

//$Header: /cvsroot/esrg/sfesrg/esrgpcpj/isepwchk/pwchk/sncheck.c,v 1.3 2002/01/31 13:16:15 dtashley Exp $
//------------------------------------------------------------------------
// Dave Ashley, 12/09/00
//------------------------------------------------------------------------
//--------------------------------------------------------------------------------
//Copyright 2001 David T. Ashley
//-------------------------------------------------------------------------------------------------
//This source code and any program in which it is compiled/used is provided under the GNU GENERAL
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//PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
//IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
//ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
//
//  16. Limitation of Liability.
//
//  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
//WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
//THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
//GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
//USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
//DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
//PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
//EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
//SUCH DAMAGES.
//
//  17. Interpretation of Sections 15 and 16.
//
//  If the disclaimer of warranty and limitation of liability provided
//above cannot be given local legal effect according to their terms,
//reviewing courts shall apply local law that most closely approximates
//an absolute waiver of all civil liability in connection with the
//Program, unless a warranty or assumption of liability accompanies a
//copy of the Program in return for a fee.
//
//                     END OF TERMS AND CONDITIONS
//
//            How to Apply These Terms to Your New Programs
//
//  If you develop a new program, and you want it to be of the greatest
//possible use to the public, the best way to achieve this is to make it
//free software which everyone can redistribute and change under these terms.
//
//  To do so, attach the following notices to the program.  It is safest
//to attach them to the start of each source file to most effectively
//state the exclusion of warranty; and each file should have at least
//the "copyright" line and a pointer to where the full notice is found.
//
//    <one line to give the program's name and a brief idea of what it does.>
//    Copyright (C) <year>  <name of author>
//
//    This program is free software: you can redistribute it and/or modify
//    it under the terms of the GNU General Public License as published by
//    the Free Software Foundation, either version 3 of the License, or
//    (at your option) any later version.
//
//    This program is distributed in the hope that it will be useful,
//    but WITHOUT ANY WARRANTY; without even the implied warranty of
//    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//    GNU General Public License for more details.
//
//    You should have received a copy of the GNU General Public License
//    along with this program.  If not, see <http://www.gnu.org/licenses/>.
//
//Also add information on how to contact you by electronic and paper mail.
//
//  If the program does terminal interaction, make it output a short
//notice like this when it starts in an interactive mode:
//
//    <program>  Copyright (C) <year>  <name of author>
//    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
//    This is free software, and you are welcome to redistribute it
//    under certain conditions; type `show c' for details.
//
//The hypothetical commands `show w' and `show c' should show the appropriate
//parts of the General Public License.  Of course, your program's commands
//might be different; for a GUI interface, you would use an "about box".
//
//  You should also get your employer (if you work as a programmer) or school,
//if any, to sign a "copyright disclaimer" for the program, if necessary.
//For more information on this, and how to apply and follow the GNU GPL, see
//<http://www.gnu.org/licenses/>.
//
//  The GNU General Public License does not permit incorporating your program
//into proprietary programs.  If your program is a subroutine library, you
//may consider it more useful to permit linking proprietary applications with
//the library.  If this is what you want to do, use the GNU Lesser General
//Public License instead of this License.  But first, please read
//<http://www.gnu.org/philosophy/why-not-lgpl.html>.
//-------------------------------------------------------------------------------------------------
//--------------------------------------------------------------------------------
// Serial number validation DLL to be used with InstallShield Express,
// Version 3.X.
//
// This DLL is patterned nearly exactly after the example from 
// InstallShield.
//
// Here are the requirements for the algorithm employed.
//   o It must not be obvious (but it isn't required to be difficult,
//     as it doesn't need to be too difficult before it isn't the
//     weakest link anymore).  It is also noteworthy that
//     a single user won't have access to more than a few valid
//     install codes, and it would be difficult to guess the
//     hash function.
//   o It must be reproducible using a Tcl script (this is a 
//     potential mechanism for generating serial numbers to go to 
//     Digibuy).  (This is the reason for the 30-bit integers--in
//     Tcl, it might not be possible to use an integer as "unsigned",
//     so the upper two bits aren't used so that algorithm will be
//     reproducible using only signed longs.)
//   o It must be computationally inexpensive.
//------------------------------------------------------------------------
// Each serial number is broken into three components, which are
// concatenated and separated by hyphens.
//
//  a)Digibuy Product Number (11 decimal digits)
//    ------------------------------------------
//    This is the product number from Digibuy, 11 characters,
//    all decimal digits.
//
//  b)Sale Number (8 decimal digits)
//    ------------------------------
//    This is the sale number, 8 decimal digits.  These numbers
//    are numbered consecutively, starting at 00000001, and
//    are unique within a product.  Another way of looking at 
//    this number is that it provides a random element so that
//    the hash code will always be different even within the 
//    same product.
//
//  c)Hash Code (6 hexadecimal digits)
//    --------------------------------
//    This is a hash generated from (a) and (b).  The 24-bit
//    hash code makes any kind of trial and error approach to
//    trying to guess a valid install code impractical.  The
//    serial number validation computes the hash code from
//    (a) and (b) and compares it to what was entered.
//------------------------------------------------------------------------
// The hash function won't be documented.  The code should be
// enough.  It has no special or educated mathematical basis.
// It is just contortion, with no mathematical basis to make it
// any more valid than any other contortion.
//------------------------------------------------------------------------
// To call the function in the DLL from InstallShield Express, there
// are two adjustments necessary.
//
//  a)The success value must be set to 200.  (I don't know why
//    that value was chosen in the example from InstallShield,
//    but it is bad luck to mess with success when you don't 
//    completely understand all the factors that may have led
//    to the selection of 200.)
//
//  b)The name of the entry point must be specified to 
//    InstallShield as _SerialCheck@20.  I do not know
//    why the compiler adds the "@20" to the name, and
//    I was not able to pursuade it to stop.  It seems to
//    work fine none the less.
//------------------------------------------------------------------------

#include <windows.h>       //  Included to allow use of MessageBox()
#include <string.h>             //  Included to allow use of string functions
#include <stdio.h>


//  DllMain:  DLL Initialization Routine:  Not used here.

__declspec(dllexport)
int WINAPI DllMain(HINSTANCE hinstDLL,DWORD fdwReason,LPVOID lpvReserved)
{
        return (1);
}

//  Definition of Return Values:
#define SN_VALID_RETURN         100             //  Return Value Indicating Success
#define SN_INVALID_RETURN       0                  //  Return Value Indicating Retry

#define SN_VALIDATION_BYPASS  (0)
   //Set TRUE if should bypass password authentication, for
   //testing.  If bypassing, all hash key digits must
   //be zero.
#define SN_ROLL_AMOUNT (1)
   //Number of bits to roll each time.

//  Function Prototypes:
int ValidateSN( HWND, LPSTR );                     //  Serial Number Validation Routine


////////////////////////////////////////////////////////////////////////////////////
//
//      SerialCheck():
//
//              Main function called by Express.  The name of this function must match the 
//      name specified in the "Settings" Tab for the "User Information" Dialog Box of 
//      your Express installation project (ie. in the "Verification Function Name" 
//      parameter).  NOTE:  This name is case-sensitive.
//
//      Prototype:      CHAR APIENTRY SerialCheck( HWND, LPSTR, LPSTR, LPSTR, LPSTR )
//
//      Parameters (supplied from Express):
//
//              hwnd                    =       Handle to the main window handle of the installation  
//              sSRCDIR                 =       Source Directory of installation ( <SRCDIR> )
//              sSUPPORTDIR             =       Source Directory of installation ( <SUPPORTDIR> )
//              sSerialNumber   =       Serial Number supplied by end-user in "User Information" dialog
//              sReserved               =       NULL and is reserved for future use.
//
//      Return Values (Sent to Express): 
//
//      (NOTE: These parameters should match those specified in your installation project)
//
//              SN_VALID_RETURN         =       Indicates Express should continue (Serial Number is valid)
//              SN_INVALID_RETURN       =       Indicates Express should retry (Serial Number is invalid)
//
////////////////////////////////////////////////////////////////////////////////////
__declspec(dllexport)
CHAR APIENTRY SerialCheck(HWND hwnd, LPSTR sSRCDIR, LPSTR sSUPPORTDIR, 
                                                  LPSTR sSerialNumber, LPSTR sReserved)
{
        //  Define Local Variables:
        int     bValidResult;   //  Validation State of Serial Number

        #if 0   //  Display MessageBox ONLY for debugging.
                //  Display Serial Number That is Received
                MessageBox(NULL, sSerialNumber, "Serial Number", MB_OK);
        #endif
        
        //  Place Serial number Validation routine Here
        //  NOTE:  The following function calls a sample validation routine.

        bValidResult = ValidateSN(hwnd, sSerialNumber);

        //  Return Proper Value Based Upon Validation Routine
        if ( bValidResult == 1 )
        {
                //  Serial Number is Valid:  Inform Express to Continue
                return (CHAR) SN_VALID_RETURN;
        }
        else
        {
                //  Serial Number is Invalid:  Inform Express to Retry
                MessageBox( hwnd, "Invalid Serial Number", "SERIAL NUMBER ERROR", 
                        MB_OK | MB_ICONEXCLAMATION );

                return (CHAR) SN_INVALID_RETURN;
        }
}
   

/* Returns a 30-bit random number based on the digit passed.
** There is no rhyme or reason to these numbers--they were
** obtained using the random function on an HP calculator.
*/
void ValidateSN_RandDigitKey(char in, unsigned long *out)
   {
   if (in == '0')
      {
      *out = 0x1C644392;
      }
   else if (in == '1')
      {
      *out = 0x292662DC;
      }
   else if (in == '2')
      {
      *out = 0x316303D8;
      }
   else if (in == '3')
      {
      *out = 0x1D660DC5;
      }
   else if (in == '4')
      {
      *out = 0x0E5E396D;
      }
   else if (in == '5')
      {
      *out = 0x069D4A3A;
      }
   else if (in == '6')
      {
      *out = 0x187DB7D5;
      }
   else if (in == '7')
      {
      *out = 0x0CAF6C5C;
      }
   else if (in == '8')
      {
      *out = 0x23A4CDFB;
      }
   else
      {
      *out = 0x27FEC1C4;
      }
   }


/* Rolls a 30-bit integer argument left by the specified
** number of places.
*/
void ValidateSN_RollLeft(unsigned long *arg, int n)
   {
   unsigned long i;

   n &= 0xF;  /* Be sure not too large. */

   while (n--)
      {
      i = *arg;
      *arg <<= 1;
      *arg &= 0x3FFFFFFE;
      if (i & 0x20000000)
         *arg |= 0x00000001;
      }
   }


/* Maps from the least significant nibble of a 30-bit
** integer to a hexadecimal digit.
*/
char ValidateSN_ToDigit(unsigned long arg)
   {
   char rv;

   arg &= 0xF;

   switch (arg)
      {
      default:
      case  0:  rv = '0'; break;
      case  1:  rv = '1'; break;
      case  2:  rv = '2'; break;
      case  3:  rv = '3'; break;
      case  4:  rv = '4'; break;
      case  5:  rv = '5'; break;
      case  6:  rv = '6'; break;
      case  7:  rv = '7'; break;
      case  8:  rv = '8'; break;
      case  9:  rv = '9'; break;
      case 10:  rv = 'A'; break;
      case 11:  rv = 'B'; break;
      case 12:  rv = 'C'; break;
      case 13:  rv = 'D'; break;
      case 14:  rv = 'E'; break;
      case 15:  rv = 'F'; break;
      }

   return rv;
   }

//Returns the upper-case version of a lower-case letter.
//Anything not a lower-case letter isn't changed.
char ValidateSN_ToUpper(char in)
   {
   if ((in >= 'a') && (in <= 'z'))
      {
      return(in - ('a'-'A'));
      }
   else
      {
      return(in);
      }
   }


////////////////////////////////////////////////////////////////////////////////////
//
//      ValidateSN():
//
//              Serial Number validation routine.  This function performs the actual
//      validation check of the serial number.
//
//      Prototype:      int ValidateSN( LPSTR )
//
//      Parameter:
//
//              sSerialNumber   =       The Serial Number provided by the end-user
//
//      Return Values:
//
//              1                               =       Indicates that the Serial Number is valid
//              0                               =       Indicates that the Serial Number is invalid
//
////////////////////////////////////////////////////////////////////////////////////

int ValidateSN( HWND hwnd, LPSTR sSerialNumber )
{
        int             iSNLen;                         
      //Length of Serial Number
   int i;
      //General indexing variable.
   unsigned long hash;
      //The hash value being calculated.
   unsigned long_temp;
      //Long temporary variable.
   char part_num[12];
      //The part number, from DigiKey, with a null terminator.
   char sale_num[9];
      //The sale number, with null terminator.
   char hash_result_in[7];
      //The hash result from the input into the serial
      //number dialog.
   char hash_result_calculated[7];
      //The hash result calculated.  This should match
      //the one input for a valid serial number.
    
   //Generally, we can count on the input InstallShield
   //Express being formatted correctly because of the
   //mask entered in the configuration.  Here guard only
   //against errors that threaten a memory overrun
   //and so forth.

   //If the validation bypass flag is set, accept anything.
   #if SN_VALIDATION_BYPASS
      return(1);
   #endif

   //The total length of the string from IntallShield
   //must be 27 characters without exception.
        iSNLen = strlen( sSerialNumber );
        // Get Length of Serial Number

   if (iSNLen != 27)
      return 0;

   //Copy the first 11 characters of the serial number
   //to the reserved area.
   for (i=0; i<11; i++)
      {
      part_num[i] = sSerialNumber[i];
      }
   part_num[11] = 0;

   #if 0
   //For development only, useful to see part number.
        MessageBox( hwnd, part_num, "PART NUMBER", 
                           MB_OK | MB_ICONEXCLAMATION );
   #endif

   //Copy the 8 digits that should be the sale number.
   for (i=0; i<8; i++)
      {
      sale_num[i] = sSerialNumber[i+12];
      }
   sale_num[8] = 0;

   #if 0
   //For development only, useful to see sale number.
        MessageBox( hwnd, sale_num, "SALE NUMBER", 
                           MB_OK | MB_ICONEXCLAMATION );
   #endif

   //Copy the six digits that should be the hash value
   for (i=0; i<6; i++)
      {
      hash_result_in[i] = sSerialNumber[i+21];
      }
   hash_result_in[6] = 0;

   #if 0
   //For development only, useful to see hash result in.
        MessageBox( hwnd, hash_result_in, "HASH_RESULT_IN", 
                           MB_OK | MB_ICONEXCLAMATION );
   #endif

   #if 1
      //Can bind to a specific product number here.  Can
      //refuse to validate if SN entered is for the wrong product.
      //Constant plugged in below.
      if (strcmp("97647784511", part_num))
         return(0);
   #endif

   //Now calculate the hash.
   hash = 0;

   //Incorporate the part number.
   for (i=0; i<11; i++)
      {
      ValidateSN_RandDigitKey(part_num[i], &long_temp);
      hash ^= long_temp;
      ValidateSN_RollLeft(&hash, SN_ROLL_AMOUNT);
      }

   //Incorporate the sale number.
   for (i=0; i<8; i++)
      {
      ValidateSN_RandDigitKey(sale_num[i], &long_temp);
      hash ^= long_temp;
      ValidateSN_RollLeft(&hash, SN_ROLL_AMOUNT);
      }

   //Stuff the hash into the calculated hash.
   for (i=5; i>=0; i--)
      {
      hash_result_calculated[i] = ValidateSN_ToDigit(hash);
      hash >>= 4;
      }
   hash_result_calculated[6] = 0;

   #if 0
   //For development only, useful to see hash result.
        MessageBox( hwnd, hash_result_calculated, "CALCULATED HASH VALUE", 
                           MB_OK | MB_ICONEXCLAMATION );
   #endif

   //The password passes if and only if each and every
   //digit is the same.
   for (i=0; i<6; i++)
      {
      if (ValidateSN_ToUpper(hash_result_in[i]) != 
          ValidateSN_ToUpper(hash_result_calculated[i]))
         {
         return(0);
         }
      }

   return(1);
}

/*
 * $Log: sncheck.c,v $
 * Revision 1.3  2002/01/31 13:16:15  dtashley
 * Version control keywords cleaned up.
 *
 * Revision 1.2  2002/01/31 13:14:32  dtashley
 * Version control keywords added to source files.
 *
 * $History: sncheck.c $
 * 
 * *****************  Version 2  *****************
 * User: Dtashley     Date: 12/22/00   Time: 3:53p
 * Updated in $/Installshield-Digibuy Password Validation DLL/Src
 * Product-specific validation added.
 * 
 * *****************  Version 1  *****************
 * User: Dtashley     Date: 12/11/00   Time: 1:36a
 * Created in $/Installshield-Digibuy Password Validation DLL/Src
 * Initial check-in.
 * 
 */

/* End of SNCHECK.C */