CHALLENG.C
/*
* This is a part of the Microsoft Source Code Samples.
* Copyright 1996 - 1998 Microsoft Corporation.
* All rights reserved.
*
* The following example demonstrates how license updates are made and
* how the challenge mechanism is used at request and update times. The
* application developer should analyze the application to determine the
* appropriate time to perform an update. For example, this application
* prints a message 20 times and the appropriate time to do an update
* was decided to be done after every 5th message was printed.
*/
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include "windows.h"
/*
* Include the MD4 header for computing the challenge.
*/
#include "md4.h"
/*
* Include the LSAPI header file.
*/
#include "lsapi.h"
/*
* Define the product name, product version, and publisher name for
* use with the licensing calls.
*/
#define MYAPP_PRODUCT_NAME "sample_product"
#define MYAPP_PRODUCT_VERSION "2.0"
#define MYAPP_PUBLISHER_NAME "sample_publishers"
/*
* Define the strings used to log a comment with the license system.
*/
#define MYAPP_REQUEST_LOG_COMMENT "Comment for the LSRequest call"
#define MYAPP_RELEASE_LOG_COMMENT "Comment for the LSRelease call"
#define MYAPP_UPDATE_LOG_COMMENT "Comment for the LSUpdate call"
/*
* The digest length is defined to be 16 according to the LSAPI spec.
*/
#define DIGESTLEN 16
/*
* Define the number of secrets
*/
#define NUMBER_OF_SECRETS 4
/*
* Define macros to indicate to the challenge routines whether we are
* doing an LSRequest or an LSUpdate
*/
#define LS_REQUEST 0
#define LS_UPDATE 1
/*
* Global variable used to determine if we are on a little endian machine
* or not.
*/
int littleEndian = 0;
/*
* Forward declarations.
*/
void PrintErrors( LS_HANDLE handle, LS_STATUS_CODE errorCode );
LS_STATUS_CODE getChallenge(
LS_CHALLENGE FAR *challenge,
LS_STR FAR *theString,
LS_ULONG unitsConsumed,
LS_ULONG unitsReserved,
LS_STR FAR *logcomment,
LS_ULONG R,
LS_ULONG X,
LS_ULONG typeOfCall);
int checkChallenge(
LS_CHALLENGE FAR *challenge,
LS_STR FAR *theString,
LS_ULONG unitsConsumed ,
LS_ULONG unitsReserved ,
LS_STR FAR *logComment ,
LS_ULONG unitsGranted ,
LS_STATUS_CODE status ,
LS_ULONG R,
LS_ULONG X,
LS_ULONG typeOfCall);
void swap( LS_STR FAR *byte1, LS_STR FAR *byte2 );
int PlaceInt( char FAR *buffer, LS_ULONG value );
__cdecl main()
{
LS_STATUS_CODE status;
unsigned long unitsGranted = 0;
LS_CHALLENGE challenge;
LS_HANDLE licenseHandle = (LS_HANDLE) NULL;
LS_ULONG R;
LS_ULONG X;
int i;
int endianTester = 1 ;
LS_STR challengeString[100];
char FAR *endianChar = NULL;
LS_ULONG Secrets[4] = { 0x7778797A, 0x31323334, 1633837924, 926431536 };
/************ the following code is for the LSAPI beta only! ************/
char szProviderPath[ MAX_PATH ];
UINT nChars;
/* install if necessary */
nChars = GetSystemDirectory( szProviderPath, sizeof( szProviderPath ) );
if ( 0 == nChars )
{
printf( "Can't get system directory, error %d.\n", GetLastError() );
}
lstrcat( szProviderPath, "\\mslsp32.dll" );
status = LSInstall( szProviderPath );
if ( LS_SUCCESS != status )
{
printf( "Cannot install LSAPI, error 0x%08lx.\n", status );
}
/* add licenses for our product */
status = LSLicenseUnitsSet( LS_ANY,
MYAPP_PUBLISHER_NAME,
MYAPP_PRODUCT_NAME,
MYAPP_PRODUCT_VERSION,
LS_LICENSE_TYPE_NODE,
LS_NULL,
1,
sizeof( Secrets ) / sizeof( *Secrets ),
Secrets );
if ( LS_SUCCESS != status )
{
printf( "Cannot install licenses, error 0x%lx.\n", status );
}
/************ the above code is for the LSAPI beta only! ************/
/*
* test endianness and set global variable by casting an int
* as bytes and look at the first byte
*/
endianChar = (char FAR *) &endianTester ;
if ( *endianChar )
littleEndian = 1 ;
/*
* Calculate the string for the challenge on the LSRequest call.
*/
sprintf( challengeString, "%s%s%s%s%s",
"LSRequest",
LS_ANY,
MYAPP_PUBLISHER_NAME,
MYAPP_PRODUCT_NAME,
MYAPP_PRODUCT_VERSION );
/*
* Pick the random number R and randomly pick a number for the index X
* between 1 and the number of secrets.
*/
srand( (unsigned)time( NULL ) );
R = rand();
X = (int)(NUMBER_OF_SECRETS * ((float)rand()/(float)RAND_MAX)) + 1;
/*
* Calculate the message digest for the challenge argument.
*/
status = getChallenge(
&challenge,
challengeString,
0, /* Unused argument for LSRequest call */
LS_DEFAULT_UNITS,
MYAPP_REQUEST_LOG_COMMENT,
R,
X,
LS_REQUEST );
if ( LS_SUCCESS != status )
{
PrintErrors( licenseHandle, status );
return(1);
}
/*
* Make the grant request call
*/
status = LSRequest(
(LS_STR FAR *) LS_ANY,
(LS_STR FAR *) MYAPP_PUBLISHER_NAME,
(LS_STR FAR *) MYAPP_PRODUCT_NAME,
(LS_STR FAR *) MYAPP_PRODUCT_VERSION,
LS_DEFAULT_UNITS,
(LS_STR FAR *) MYAPP_REQUEST_LOG_COMMENT,
&challenge,
&unitsGranted,
&licenseHandle);
if ( LS_SUCCESS != status )
{
PrintErrors( licenseHandle, status );
LSFreeHandle( licenseHandle );
return(1);
}
/*
* Check whether the challenge succeeded.
*/
if ( !checkChallenge(
&challenge,
challengeString,
0, /* Unused argument for LSRequest call */
LS_DEFAULT_UNITS,
MYAPP_REQUEST_LOG_COMMENT,
unitsGranted,
status,
R,
X,
LS_REQUEST ) )
{
printf("Challenge failed!!!\n");
/*
* Since we failed, we should still release the grant and free
* the license handle.
*/
status = LSRelease( licenseHandle,
LS_DEFAULT_UNITS,
(LS_STR FAR *) MYAPP_RELEASE_LOG_COMMENT);
if ( LS_SUCCESS != status )
PrintErrors( licenseHandle, status );
LSFreeHandle( licenseHandle );
return(1);
}
/*
* Now we can start the application. Print "Hello, World" 20 times
* performing an update after every 5th time.
*/
for ( i = 0; i<20; i++ )
{
printf("Hello, World.\n");
if ( 0 == i%5 )
{
/*
* Calculate the challenge string for the challenge on
* the LSUpdate call.
*/
sprintf( challengeString, "%s", "LSUpdate");
/*
* Pick the random number R using the process id for the seed
* to the random number generator. Also randomly pick a number
* for the index X between 1 and NUMBER_OF_SECRETS.
*/
srand( (unsigned)time( NULL ) );
R = rand();
X = (int)(NUMBER_OF_SECRETS * ((float)rand()/(float)RAND_MAX)) + 1;
/*
* Calculate the message digest for the challenge argument.
*/
status = getChallenge(
&challenge,
challengeString,
LS_DEFAULT_UNITS,
LS_DEFAULT_UNITS,
MYAPP_UPDATE_LOG_COMMENT,
R,
X,
LS_UPDATE );
if ( LS_SUCCESS != status )
{
PrintErrors( licenseHandle, status );
status = LSRelease( licenseHandle,
LS_DEFAULT_UNITS,
(LS_STR FAR *) MYAPP_RELEASE_LOG_COMMENT);
LSFreeHandle( licenseHandle );
return(1);
}
/*
* Make the update call.
*/
status = LSUpdate( licenseHandle,
LS_DEFAULT_UNITS,
LS_DEFAULT_UNITS,
(LS_STR FAR *) MYAPP_UPDATE_LOG_COMMENT,
&challenge,
&unitsGranted);
if ( LS_SUCCESS != status )
{
PrintErrors( licenseHandle, status );
status = LSRelease( licenseHandle,
LS_DEFAULT_UNITS,
(LS_STR FAR *) MYAPP_RELEASE_LOG_COMMENT);
LSFreeHandle( licenseHandle );
return( 1 );
}
/*
* Check whether the challenge succeeded.
*/
if ( !checkChallenge(
&challenge,
challengeString,
LS_DEFAULT_UNITS,
LS_DEFAULT_UNITS,
MYAPP_UPDATE_LOG_COMMENT,
unitsGranted,
status,
R,
X,
LS_UPDATE ) )
{
printf("Challenge failed!!!\n");
/*
* Release the grant.
*/
status = LSRelease( licenseHandle,
LS_DEFAULT_UNITS,
(LS_STR FAR *) MYAPP_RELEASE_LOG_COMMENT);
if ( LS_SUCCESS != status )
PrintErrors( licenseHandle, status );
LSFreeHandle( licenseHandle );
return(1);
}
} /* End of if ( 0 == i%5 ) */
} /* End of for loop. */
/*
* Release the grant.
*/
status = LSRelease( licenseHandle,
LS_DEFAULT_UNITS,
(LS_STR FAR *) MYAPP_RELEASE_LOG_COMMENT);
if ( LS_SUCCESS != status )
{
PrintErrors( licenseHandle, status );
LSFreeHandle( licenseHandle );
return( 1 );
}
/*
* Free the license handle.
*/
LSFreeHandle( licenseHandle );
return(0);
}
/*
* Print the error message.
*/
void PrintErrors( LS_HANDLE handle, LS_STATUS_CODE errorCode )
{
LS_STATUS_CODE status;
char errorText[200];
status = LSGetMessage( handle, errorCode, (LS_STR FAR *)errorText, 200);
if ( LS_TEXT_UNAVAILABLE == status )
printf("Error: No message catalog available.\n");
else
if ( LS_UNKNOWN_STATUS == status )
printf("Error: Unknown error code was used.\n");
else
printf("Error: %s\n", errorText);
}
/*
* Use the algorithmic approach to calculate the message digest to send
* to the server.
*/
LS_STATUS_CODE getChallenge(
LS_CHALLENGE FAR *challenge,
LS_STR FAR *theString,
LS_ULONG unitsConsumed,
LS_ULONG unitsReserved,
LS_STR FAR *logComment,
LS_ULONG R,
LS_ULONG X,
LS_ULONG typeOfCall)
{
MD4_CTX MD;
char secret[4];
LS_STR hashString[200], FAR *hashStringPtr;
int bufferLen, bytes, i;
/*
* Set the protocol, index, random number, and size on the challenge
* argument.
*/
challenge->Protocol = LS_BASIC_PROTOCOL;
challenge->ChallengeData.SecretIndex = X;
challenge->ChallengeData.Random = R;
/*
* Get the secret. NOTE: Greater steps should be taken to obsure the
* secrets than is shown. Also, more secrets should be used than 4.
* Several methods are shown on how the secret can be specified.
*/
switch ( X )
{
case 1:
PlaceInt( secret, 0x7778797A );
break;
case 2:
PlaceInt( secret, 0x31323334 );
break;
case 3:
PlaceInt( secret, 1633837924 );
break;
case 4:
PlaceInt( secret, 926431536 );
break;
default:
printf("Index out of range\n");
return( 0 );
break;
}
/*
* Compute the hash string to be used on input to the MD4 algorithm.
*/
strcpy( hashString, theString );
hashStringPtr = hashString + strlen( theString );
bufferLen = strlen( theString );
/*
* Add units consumed only for LSUpdate call
*/
if ( LS_UPDATE == typeOfCall )
{
bytes = PlaceInt( hashStringPtr, (LS_ULONG) unitsConsumed );
hashStringPtr += bytes;
bufferLen += bytes;
}
bytes = PlaceInt( hashStringPtr, (LS_ULONG) unitsReserved );
hashStringPtr += bytes;
bufferLen += bytes;
strcpy( hashStringPtr, logComment );
bufferLen += strlen( logComment );
hashStringPtr += strlen( logComment );
bytes = PlaceInt( hashStringPtr, (LS_ULONG) R );
hashStringPtr += bytes;
bufferLen += bytes;
bytes = PlaceInt( hashStringPtr, (LS_ULONG) X );
hashStringPtr += bytes;
bufferLen += bytes;
for ( i=0; i<4; i++ )
{
*hashStringPtr = secret[i];
hashStringPtr++;
bufferLen++;
}
/*
* Make the MD4 calls.
*/
MD4Init(&MD);
MD4Update(
(MD4_CTX *) &MD,
(unsigned char *) hashString,
(unsigned int) bufferLen );
MD4Final(
challenge->ChallengeData.MsgDigest.MessageDigest,
(MD4_CTX *) &MD);
challenge->Size = sizeof( challenge->ChallengeData );
return( LS_SUCCESS );
}
/*
* Check the return challenge argument.
*/
int checkChallenge(
LS_CHALLENGE FAR *challenge,
LS_STR FAR *theString,
LS_ULONG unitsConsumed ,
LS_ULONG unitsReserved ,
LS_STR FAR *logComment ,
LS_ULONG unitsGranted ,
LS_STATUS_CODE status ,
LS_ULONG R,
LS_ULONG X,
LS_ULONG typeOfCall)
{
char secret[4];
MD4_CTX MD;
LS_STR hashString[200];
LS_STR digest[DIGESTLEN], FAR *hashStringPtr;
int i, bufferLen, bytes, j;
/*
* Get the secret. NOTE: Greater steps should be taken to obsure the
* secrets than is shown. Also, more secrets should be used than 4.
* Several methods are shown on how the secret can be specified.
*/
switch ( X )
{
case 1:
PlaceInt( secret, 0x7778797A );
break;
case 2:
PlaceInt( secret, 0x31323334 );
break;
case 3:
PlaceInt( secret, 1633837924 );
break;
case 4:
PlaceInt( secret, 926431536 );
break;
default:
printf("Index out of range\n");
return( 0 );
break;
}
/*
* Compute the hash string.
*/
strcpy( hashString, theString );
hashStringPtr = hashString + strlen( theString );
bufferLen = strlen( theString );
/*
* Add units consumed only for LSUpdate call
*/
if ( LS_UPDATE == typeOfCall )
{
bytes = PlaceInt( hashStringPtr, (LS_ULONG) unitsConsumed );
hashStringPtr += bytes;
bufferLen += bytes;
}
bytes = PlaceInt( hashStringPtr, (LS_ULONG) unitsReserved );
hashStringPtr += bytes;
bufferLen += bytes;
strcpy( hashStringPtr, logComment );
bufferLen += strlen( logComment );
hashStringPtr += strlen( logComment );
bytes = PlaceInt( hashStringPtr, (LS_ULONG) unitsGranted );
hashStringPtr += bytes;
bufferLen += bytes;
bytes = PlaceInt( hashStringPtr, (LS_ULONG) status );
hashStringPtr += bytes;
bufferLen += bytes;
bytes = PlaceInt( hashStringPtr, (LS_ULONG) R );
hashStringPtr += bytes;
bufferLen += bytes;
bytes = PlaceInt( hashStringPtr, (LS_ULONG) X );
hashStringPtr += bytes;
bufferLen += bytes;
for ( i=0; i<4; i++ )
{
*hashStringPtr = secret[i];
hashStringPtr++;
bufferLen++;
}
/*
* Compute the message digest.
*/
MD4Init(&MD);
MD4Update(
(MD4_CTX *) &MD,
(unsigned char *) hashString,
(unsigned int) bufferLen );
MD4Final(
digest,
(MD4_CTX *) &MD);
/*
* Compare the digest with the one on the challenge
*/
j = 0 ;
for( i = 0; i < DIGESTLEN; i++ )
{
if( digest[i] != challenge->ChallengeData.MsgDigest.MessageDigest[i] )
break ;
j++ ;
}
if( j == DIGESTLEN )
return( 1 );
return( 0 );
}
/*
* swap bytes
*/
void swap( LS_STR FAR *byte1, LS_STR FAR *byte2 )
{
LS_STR tmp;
tmp = *byte2;
*byte2 = *byte1;
*byte1 = tmp;
}
/*
* Places integer in byte buffer, swapping bytes if necessary
*/
int PlaceInt( char FAR *buffer, LS_ULONG value )
{
if ( littleEndian )
{
swap(&(((char FAR *) &value)[0]), &(((char FAR *) &value)[3]));
swap(&(((char FAR *) &value)[1]), &(((char FAR *) &value)[2]));
}
memcpy( buffer, &value, sizeof( LS_ULONG ) );
return( (int) sizeof( LS_ULONG ) );
}