keyvil: detectBytes

int detectBytes	(	const char *	cryptoMethod,
		const char *	referenceInputBytes,
		int	inputLength,
		const char *	presetIterationBytes,
		const char *	referenceOutputBytes,
		char *	detectedIterationBytes
	)
Definition at line 35 of file compare.cpp.
00035                                                                                                                                                                                               {
00036         /*declaration block*/
00037         char* currentOutput = NULL;
00038         int lengthCurrentOutput = 0;
00039         char* iterationWord = NULL;
00040         usedIntType* pVariableIntPart = NULL;
00041         bool found = false;
00042         bool methodSupported = true;
00043         int index = 0;
00044         cryptoFunction function = NULL;
00045         
00046 
00047         /*input validation*/
00048         if ( referenceOutputBytes == NULL ) {
00049                 printf("compare(): no reference hash delivered. exiting...\n");
00050                 return DETECT_BYTES_WRONG_PARAMETER_ERROR;
00051         }
00052 
00053 
00054         /*look for a function pointer for the given crypto method*/
00055         function = getFunctionPointer(cryptoMethod);
00056         if ( !function ) {
00057                 //printf("compare(): there is no crypto function \"%s\" specified in \"cryptoFunctions.h\". exiting...\n", cryptoMethod);
00058                 return DETECT_BYTES_METHOD_NOT_SUPPORTED;
00059         }
00060 
00061 
00062         /*initialization block*/
00063         currentOutput = NULL;   /*the output length depends on the crypto method and space is alocated in the implementation therefore*/
00064         /*allocates space for the preset bytes, the used int type plus one '\0'*/
00065         /*calloc sets all allocated bytes to null*/
00066         iterationWord = (char*)calloc(LENGTH_GIVEN_BYTES+LENGTH_DETECTED_BYTES+1, 1);
00067         /*copy the preset bytes to our input word*/
00068         index = 0;
00069         while ( index < LENGTH_GIVEN_BYTES ) {
00070                 iterationWord[index] = presetIterationBytes[index];
00071                 index++;
00072         }
00073         /*mark the beginning of the input word's variable part int pointer*/
00074         pVariableIntPart = (usedIntType*)(iterationWord + LENGTH_GIVEN_BYTES);
00075         
00076         /*do the main comparison loop*/
00077         found = false;
00078         methodSupported = true;
00079         do {
00080                 /*create a cancelation point in the main loop*/
00081                 pthread_testcancel();
00082 #ifdef _DEBUG_
00083                 /*debug-output*/
00084                 printf("%u: \"%s\" \n",*pVariableIntPart , iterationWord);
00085 #endif
00086                 /*calculate the hash to the current input word*/
00087                 lengthCurrentOutput = function((const unsigned char*)referenceInputBytes, inputLength, (const unsigned char*)iterationWord, (unsigned char**)&currentOutput);
00088                 if (lengthCurrentOutput == DETECT_BYTES_METHOD_NOT_SUPPORTED) {
00089                         methodSupported = false;
00090                 }
00091 #ifdef _DEBUG_
00092                 if ( referenceInputBytes ) {
00093                         printf("Input:     ");
00094                         printHashBytes((const char*)referenceInputBytes,inputLength);
00095                         printf("\n");
00096                 }
00097                 printf("Iteration: ");
00098                 printHashBytes((const char*)iterationWord,LENGTH_ITERATION_WORD);
00099                 printf("\n");
00100                 printf("Output:    ");
00101                 printHashBytes(currentOutput,lengthCurrentOutput);
00102                 printf("\n\n");
00103 #endif
00104                 if (methodSupported) {
00105                         /*check for match*/
00106                         found = isEqual(currentOutput, referenceOutputBytes, lengthCurrentOutput);
00107                 }
00108                 /*increase the variable int part of the word*/
00109                 (*pVariableIntPart)++;
00110                 //sleep(2);
00111         } while ( !found && methodSupported && *pVariableIntPart > 0 );
00112         
00113         /*check if a match was found*/
00114         if ( found ) {
00115                 (*pVariableIntPart)--;
00116                 *((usedIntType*)detectedIterationBytes) = *pVariableIntPart;
00117         }
00118 
00119         /*free the corresponding variables*/
00120         free(currentOutput);
00121         free(iterationWord);
00122 
00123         /*return the end status of comparing*/
00124         if (found) {
00125                 return DETECT_BYTES_DETECTED;
00126         }
00127         else if (methodSupported) {
00128                 return DETECT_BYTES_NOT_DETECTED;
00129         }
00130         /*else*/
00131         return DETECT_BYTES_METHOD_NOT_SUPPORTED;
00132 }