#!/usr/bin/perl -w
#
# Author:      tlviewer@yahoo.com
# script:	PrimeGen.pl
# Description: use the CryptoAPI to generate
#			Diffie Hellman Prime/Gen pairs for Perl
# keywords:  prime cryptoapi crypt diffie inline ingie
# Date:       10/31/04

use Inline C => DATA => LIBS => '-luser32 -lcrypt32 ';

my $tStart = Win32::GetTickCount();
my $lret;
my ( $prime, $gen );

# generate the Prime/Gen pairs at the desired modulus length
for my $i ( 0 .. 4 ) {
    $lret = main( $prime, $gen, 1536 );
    print "prime=", unpack( "H*", $prime ), "\n";
    print "gen  =", unpack( "H*", $gen ),   "\n\n";
}

# /*  Win32 only way to get the elapsed time */
print "elapsed=", ( Win32::GetTickCount() - $tStart ) / 1000, " seconds\n";

#
	__END__
	__C__
	/* test  */
#define _WIN32_WINNT 0x0500
#include <stdio.h>
#include <windows.h>
#include <wincrypt.h>
#define MY_ENCODING_TYPE  (PKCS_7_ASN_ENCODING | X509_ASN_ENCODING) 

int main( SV* prime, SV* gen, int modulen)
{ 
 
 /* cryptoapi defs   */	
 HCRYPTPROV prov1; 
 HCRYPTKEY hKey1; 
 CRYPT_DATA_BLOB  blob;

/* standard C defs  */ 
 BYTE  DataPom[1024];  
 unsigned long Velikost2 = 1024,Velikost = 12;
 DWORD dwNJ=0;  

/* delete the container if there  */
CryptAcquireContext(&prov1, "PrimeGen", 
	MS_ENH_DSS_DH_PROV, PROV_DSS_DH, 
	CRYPT_DELETEKEYSET);

/*  get context using no private keys */
 if (!CryptAcquireContext(&prov1, "PrimeGen", 
 	MS_ENH_DSS_DH_PROV, PROV_DSS_DH,
 	CRYPT_VERIFYCONTEXT))
 {
	 //printf("container is not defined \n");
	 printf("\n");
  if (!CryptAcquireContext(&prov1, "PrimeGen", 
  		MS_ENH_DSS_DH_PROV, PROV_DSS_DH, 
  		CRYPT_NEWKEYSET))
  {
   printf("Error 1: %x(%d)\n", GetLastError(), GetLastError()); 
   exit(1);
  }
  else
  { 
  	/* generate the epemeral key pair and DH parameters  */
	  //printf("trying to generate new key \n");
	if (!CryptGenKey(prov1, CALG_DH_EPHEM, 
			( modulen << 16 )  , &hKey1))
	 {
	  printf("Error 3: %x(%d)\n", GetLastError(), GetLastError());
	 }
  }
 }

Velikost2 = 0; 

/*  get a pointer to the Gen length */
if (!CryptGetKeyParam(hKey1, KP_G, 0,  &Velikost2, 0))
{
	printf("Error 9: %x(%d)\n", GetLastError(), GetLastError());
}
 //printf("BufSize=%d \n", Velikost2); 
 
/*  zero out the buffer */ 
for (dwNJ=0;dwNJ<Velikost2;dwNJ++){
	 (BYTE) DataPom[dwNJ] = 0x0;
}

/*  now get the Gen value into DataPom */
 if (!CryptGetKeyParam(hKey1, KP_G, DataPom, &Velikost2, 0))
 {
  printf("Error 9: %x(%d)\n", GetLastError(), GetLastError());
 }
 
 /* what voodoo! put the byte pointer into our perl scalar value  */   
 sv_setpvn( gen,  DataPom, Velikost2);

/*  same as above except for the prime */
Velikost2 = 0;
if (!CryptGetKeyParam(hKey1, KP_P, 0, &Velikost2, 0))
 {
  printf("Error 11: %x(%d)\n", GetLastError(), GetLastError());
 }

 if (!CryptGetKeyParam(hKey1, KP_P, DataPom, &Velikost2, 0))
 {
  printf("Error 11: %x(%d)\n", GetLastError(), GetLastError());
 }  
 
 /*    use for debugging
 printf("Prime=");
 for (dwNJ=0;dwNJ<Velikost2;dwNJ++){
		printf( "%02x", (BYTE) DataPom[dwNJ]);
	}
 printf("\n"); 
 */
 
 sv_setpvn( prime,  DataPom, Velikost2);

 //free(DataPom);
	if (CryptDestroyKey(hKey1))
	{
		// it worked
	} 
 
 if (!CryptReleaseContext(prov1, 0))
  printf("Error 2: %x(%d)\n", GetLastError(), GetLastError());

 return dwNJ;
}