reveng -g (model search given just hexstr with crc)

client/cmdcrc.c

@@ -54,7 +54,7 @@ int split(char *str, char *arr[MAX_ARGS]){
 		char *tmp = calloc(len + 1, sizeof(char));
 		memcpy(tmp, &str[beginIndex], len);
 		arr[wordCnt++] = tmp;
-		//PrintAndLog("cnt: %d, %s",wordCnt-1, arr[wordCnt-1]);
+		//PrintAndLog("DEBUG cnt: %d, %s",wordCnt-1, arr[wordCnt-1]);
 		beginIndex = endIndex;
 		if (wordCnt == maxWords)
 			break;
@@ -70,17 +70,23 @@ int CmdCrc(const char *Cmd)
 	memcpy(Cmd2 + 7, Cmd, 50);
 	char *argv[MAX_ARGS];
 	int argc = split(Cmd2, argv);
-	//PrintAndLog("argc: %d, %s %s Cmd: %s",argc, argv[0], Cmd2, Cmd);
+
-	reveng_main(argc, argv);
+	if (argc == 3 && memcmp(argv[1],"-g",2)==0) {
+		CmdrevengSearch(argv[2]);
+	} else {
+		reveng_main(argc, argv);
+	}
+	//PrintAndLog("DEBUG argc: %d, %s %s Cmd: %s",argc, argv[0], Cmd2, Cmd);
 	for(int i = 0; i < argc; ++i){
-		//puts(arr[i]);
 		free(argv[i]);
 	}
 
 	return 0;
 }
 
-int GetModels(char *Models[], int *count, uint32_t *width){
+//returns array of model names and the count of models returning
+//  as well as a width array for the width of each model
+int GetModels(char *Models[], int *count, uint8_t *width){
 	/* default values */
 	static model_t model = {
 		PZERO,		/* no CRC polynomial, user must specify */
@@ -105,7 +111,7 @@ int GetModels(char *Models[], int *count, uint32_t *width){
 	
 	int args = 0, psets, pass;
 	int Cnt = 0;
-	if (*width == 0) { //reveng -D
+	if (width[0] == 0) { //reveng -D
 		*count = mcount();
 		if(!*count)
 			return uerr("no preset models available");
@@ -120,6 +126,7 @@ int GetModels(char *Models[], int *count, uint32_t *width){
 
 			memcpy(tmp, model.name, size);
 			Models[mode] = tmp;
+			width[mode] = plen(model.spoly);
 		}
 		mfree(&model);
 	} else { //reveng -s
@@ -127,13 +134,13 @@ int GetModels(char *Models[], int *count, uint32_t *width){
 		if(~model.flags & P_MULXN)
 			return uerr("cannot search for non-Williams compliant models");
 
-		praloc(&model.spoly, *width);
+		praloc(&model.spoly, (unsigned long)width[0]);
-		praloc(&model.init, *width);
+		praloc(&model.init, (unsigned long)width[0]);
-		praloc(&model.xorout, *width);
+		praloc(&model.xorout, (unsigned long)width[0]);
 		if(!plen(model.spoly))
-			palloc(&model.spoly, *width);
+			palloc(&model.spoly, (unsigned long)width[0]);
 		else
-			*width = plen(model.spoly);
+			width[0] = (uint8_t)plen(model.spoly);
 
 		/* special case if qpoly is zero, search to end of range */
 		if(!ptst(qpoly))
@@ -173,7 +180,7 @@ int GetModels(char *Models[], int *count, uint32_t *width){
 					mbynum(&pset, --psets);
 					
 					/* skip if different width, or refin or refout don't match */
-					if(plen(pset.spoly) != *width || (model.flags ^ pset.flags) & (P_REFIN | P_REFOUT))
+					if(plen(pset.spoly) != width[0] || (model.flags ^ pset.flags) & (P_REFIN | P_REFOUT))
 						continue;
 					/* skip if the preset doesn't match specified parameters */
 					if(rflags & R_HAVEP && pcmp(&model.spoly, &pset.spoly))
@@ -210,6 +217,7 @@ int GetModels(char *Models[], int *count, uint32_t *width){
 							PrintAndLog("out of memory?");
 							return 0;
 						}
+						width[Cnt] = width[0];
 						memcpy(tmp, pset.name, size);
 						Models[Cnt++] = tmp;
 						*count = Cnt;
@@ -264,18 +272,20 @@ int GetModels(char *Models[], int *count, uint32_t *width){
 int CmdrevengTest(const char *Cmd){
 	char *Models[80];
 	int count = 0;
-	uint32_t width = 0;
+	uint8_t widtharr[80] = {0};
+	uint8_t width = 0;
 	width = param_get8(Cmd, 0);
 	//PrintAndLog("width: %d",width);
 	if (width > 89)
 		return uerr("Width cannot exceed 89");
 
-	int ans = GetModels(Models, &count, &width);
+	widtharr[0] = width;
+	int ans = GetModels(Models, &count, widtharr);
 	if (!ans) return 0;
 	
 	PrintAndLog("Count: %d",count);
 	for (int i = 0; i < count; i++){
-		PrintAndLog("Model %d: %s",i,Models[i]);
+		PrintAndLog("Model %d: %s, width: %d",i,Models[i], widtharr[i]);
 		free(Models[i]);
 	}
 	return 1;
@@ -438,3 +448,100 @@ int CmdrevengTestC(const char *Cmd){
 	PrintAndLog("Result: %s",result);
 	return 1;
 }
+
+//returns a calloced string (needs to be freed)
+char *SwapEndianStr(const char *inStr, const size_t len, const uint8_t blockSize){
+	char *tmp = calloc(len+1, sizeof(char));
+	for (uint8_t block=0; block < (uint8_t)(len/blockSize); block++){
+		for (size_t i = 0; i < blockSize; i+=2){
+			tmp[i+(blockSize*block)] = inStr[(blockSize-1-i-1)+(blockSize*block)];
+			tmp[i+(blockSize*block)+1] = inStr[(blockSize-1-i)+(blockSize*block)];
+		}
+	}
+	return tmp;
+}
+
+// takes hex string in and searches for a matching result (hex string must include checksum)
+int CmdrevengSearch(const char *Cmd){
+	char inHexStr[50] = {0x00};
+	int dataLen = param_getstr(Cmd, 0, inHexStr);
+	if (dataLen < 4) return 0;
+
+	char *Models[80];
+	int count = 0;
+	uint8_t width[80];
+	width[0] = 0;
+	uint8_t crcChars = 0;
+	char result[30];
+	char revResult[30];
+	int ans = GetModels(Models, &count, width);
+	bool found = false;
+	if (!ans) return 0;
+	
+	// try each model and get result
+	for (int i = 0; i < count; i++){
+		/*if (found) {
+			free(Models[i]);
+			continue;
+		}*/
+		// round up to # of characters in this model's crc
+		crcChars = ((width[i]+7)/8)*2; 
+		// can't test a model that has more crc digits than our data
+		if (crcChars >= dataLen) 
+			continue;
+		memset(result, 0, 30);
+		char *inCRC = calloc(crcChars+1, sizeof(char));
+		memcpy(inCRC, inHexStr+(dataLen-crcChars), crcChars);
+
+		char *outHex = calloc(dataLen-crcChars+1, sizeof(char));
+		memcpy(outHex, inHexStr, dataLen-crcChars);
+
+		//PrintAndLog("DEBUG: dataLen: %d, crcChars: %d, Model: %s, CRC: %s, width: %d, outHex: %s",dataLen, crcChars, Models[i], inCRC, width[i], outHex);
+		ans = RunModel(Models[i], outHex, false, 0, result);
+		if (ans) {
+			//test for match
+			if (memcmp(result, inCRC, crcChars)==0){
+				PrintAndLog("\nFound a match!\nModel: %s\nValue: %s\n",Models[i], result);
+				//optional - stop searching if found...
+				found = true;
+			} else {
+				if (crcChars > 2){
+					char *swapEndian = SwapEndianStr(result, crcChars, crcChars);
+					if (memcmp(swapEndian, inCRC, crcChars)==0){
+						PrintAndLog("\nFound a match!\nModel: %s\nValue EndianSwapped: %s\n",Models[i], swapEndian);
+						//optional - stop searching if found...
+						found = true;
+					}
+					free(swapEndian);
+				}
+			}
+		}
+		
+		//if (!found){
+			ans = RunModel(Models[i], outHex, true, 0, revResult);
+			if (ans) {
+				//test for match
+				if (memcmp(revResult, inCRC, crcChars)==0){
+					PrintAndLog("\nFound a match!\nModel Reversed: %s\nValue: %s\n",Models[i], revResult);
+					//optional - stop searching if found...
+					found = true;
+				} else {
+					if (crcChars > 2){
+						char *swapEndian = SwapEndianStr(revResult, crcChars, crcChars);
+						if (memcmp(swapEndian, inCRC, crcChars)==0){
+							PrintAndLog("\nFound a match!\nModel Reversed: %s\nValue EndianSwapped: %s\n",Models[i], swapEndian);
+							//optional - stop searching if found...
+							found = true;
+						}
+						free(swapEndian);
+					}
+				}
+			}
+		//}
+		free(inCRC);
+		free(outHex);
+		free(Models[i]);
+	}
+	if (!found) PrintAndLog("\nNo matches found\n");
+	return 1;
+}

client/cmdcrc.h

@@ -14,6 +14,7 @@
 int CmdCrc(const char *Cmd);
 int CmdrevengTest(const char *Cmd);
 int CmdrevengTestC(const char *Cmd);
-int GetModels(char *Models[], int *count, uint32_t *width);
+int CmdrevengSearch(const char *Cmd);
+int GetModels(char *Models[], int *count, uint8_t *width);
 int RunModel(char *inModel, char *inHexStr, bool reverse, char endian, char *result);
 #endif

client/cmdmain.c

@@ -37,8 +37,8 @@ static int CmdRev(const char *Cmd);
 /*
 static int CmdrevengT(const char *Cmd);
 static int CmdrevengC(const char *Cmd);
+static int CmdrevengA(const char *Cmd);
 */
-
 //For storing command that are received from the device
 static UsbCommand cmdBuffer[CMD_BUFFER_SIZE];
 //Points to the next empty position to write to
@@ -54,10 +54,11 @@ static command_t CommandTable[] =
   {"hw",    CmdHW,    1, "{ Hardware commands... }"},
   {"lf",    CmdLF,    1, "{ Low Frequency commands... }"},
   {"reveng",CmdRev,   1, "Crc calculations from the software reveng1-30"},
-   // for testing reveng api - cmdcrc.c
+  /* // for testing reveng api - cmdcrc.c
-  //{"revengt",CmdrevengT,1, "TEST Crc calculations from the software reveng1-30"},
+  {"revenga",CmdrevengA,1, "TEST Crc calculations from the software reveng1-30"},
-  //{"revengc",CmdrevengC,1, "TEST Crc calculations from the software reveng1-30"},
+  {"revengt",CmdrevengT,1, "TEST Crc calculations from the software reveng1-30"},
-  
+  {"revengc",CmdrevengC,1, "TEST Crc calculations from the software reveng1-30"},
+  */
   {"script",CmdScript,1, "{ Scripting commands }"},
   {"quit",  CmdQuit,  1, "Exit program"},
   {"exit",  CmdQuit,  1, "Exit program"},
@@ -85,8 +86,12 @@ int CmdRev(const char *Cmd)
   CmdCrc(Cmd);
   return 0;
 }
-/*
+
- // for testing reveng api - cmdcrc.c
+/* // for testing reveng api - cmdcrc.c
+int CmdrevengA(const char *Cmd)
+{
+  return CmdrevengSearch(Cmd);
+}
 int CmdrevengT(const char *Cmd)
 {
   return CmdrevengTest(Cmd);

client/scripting.c

@@ -397,8 +397,9 @@ static int l_reveng_models(lua_State *L){
 	
 	if( in_width > 89 ) return returnToLuaWithError(L,"Width cannot exceed 89, got %d", in_width);
 
-	uint32_t width = (uint32_t)in_width;
+	uint8_t width[80];
-	int ans = GetModels(models, &count, &width);
+	width[0] = (uint8_t)in_width;
+	int ans = GetModels(models, &count, width);
 	if (!ans) return 0;
 	
 	lua_newtable(L);