git.zerfleddert.de Git - proxmark3-svn/blob - client/cmdanalyse.c

   1 //-----------------------------------------------------------------------------
   2 // Copyright (C) 2016 iceman
   3 //
   4 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
   5 // at your option, any later version. See the LICENSE.txt file for the text of
   6 // the license.
   7 //-----------------------------------------------------------------------------
   8 // Analyse bytes commands
   9 //-----------------------------------------------------------------------------
  10 #include "cmdanalyse.h"
  11
  12 static int CmdHelp(const char *Cmd);
  13
  14 int usage_analyse_lcr(void) {
  15         PrintAndLog("Specifying the bytes of a UID with a known LRC will find the last byte value");
  16         PrintAndLog("needed to generate that LRC with a rolling XOR. All bytes should be specified in HEX.");
  17         PrintAndLog("");
  18         PrintAndLog("Usage:  analyse lcr [h] <bytes>");
  19         PrintAndLog("Options:");
  20         PrintAndLog("           h          This help");
  21         PrintAndLog("           <bytes>    bytes to calc missing XOR in a LCR");
  22         PrintAndLog("");
  23         PrintAndLog("Samples:");
  24         PrintAndLog("           analyse lcr 04008064BA");
  25         PrintAndLog("expected output: Target (BA) requires final LRC XOR byte value: 5A");
  26         return 0;
  27 }
  28
  29 int usage_analyse_checksum(void) {
  30         PrintAndLog("The bytes will be added with eachother and than limited with the applied mask");
  31         PrintAndLog("Finally compute ones' complement of the least significant bytes");
  32         PrintAndLog("");
  33         PrintAndLog("Usage:  analyse chksum [h] b <bytes> m <mask>");
  34         PrintAndLog("Options:");
  35         PrintAndLog("           h          This help");
  36         PrintAndLog("           b <bytes>  bytes to calc missing XOR in a LCR");
  37         PrintAndLog("           m <mask>   bit mask to limit the outpuyt");
  38         PrintAndLog("");
  39         PrintAndLog("Samples:");
  40         PrintAndLog("           analyse chksum b 137AF00A0A0D m FF");
  41         PrintAndLog("expected output: 0x61");
  42         return 0;
  43 }
  44
  45 int usage_analyse_crc(void){
  46         PrintAndLog("A stub method to test different crc implementations inside the PM3 sourcecode. Just because you figured out the poly, doesn't mean you get the desired output");
  47         PrintAndLog("");
  48         PrintAndLog("Usage:  analyse crc [h] <bytes>");
  49         PrintAndLog("Options:");
  50         PrintAndLog("           h          This help");
  51         PrintAndLog("           <bytes>    bytes to calc crc");
  52         PrintAndLog("");
  53         PrintAndLog("Samples:");
  54         PrintAndLog("           analyse crc 137AF00A0A0D");
  55         return 0;
  56 }
  57
  58 static uint8_t calculateLRC( uint8_t* bytes, uint8_t len) {
  59     uint8_t LRC = 0;
  60     for (uint8_t i = 0; i < len; i++)
  61         LRC ^= bytes[i];
  62     return LRC;
  63 }
  64
  65 static uint8_t calcSumCrumbAdd( uint8_t* bytes, uint8_t len, uint32_t mask) {
  66     uint8_t sum = 0;
  67     for (uint8_t i = 0; i < len; i++) {
  68         sum += CRUMB(bytes[i], 0);
  69                 sum += CRUMB(bytes[i], 2);
  70                 sum += CRUMB(bytes[i], 4);
  71                 sum += CRUMB(bytes[i], 6);
  72         }
  73         sum &= mask;
  74     return sum;
  75 }
  76 static uint8_t calcSumCrumbAddOnes( uint8_t* bytes, uint8_t len, uint32_t mask) {
  77         return ~calcSumCrumbAdd(bytes, len, mask);
  78 }
  79 static uint8_t calcSumNibbleAdd( uint8_t* bytes, uint8_t len, uint32_t mask) {
  80     uint8_t sum = 0;
  81     for (uint8_t i = 0; i < len; i++) {
  82         sum += NIBBLE_LOW(bytes[i]);
  83                 sum += NIBBLE_HIGH(bytes[i]);
  84         }
  85         sum &= mask;
  86     return sum;
  87 }
  88 static uint8_t calcSumNibbleAddOnes( uint8_t* bytes, uint8_t len, uint32_t mask){
  89         return ~calcSumNibbleAdd(bytes, len, mask);
  90 }
  91
  92 static uint8_t calcSumByteAdd( uint8_t* bytes, uint8_t len, uint32_t mask) {
  93     uint8_t sum = 0;
  94     for (uint8_t i = 0; i < len; i++)
  95         sum += bytes[i];
  96         sum &= mask;
  97     return sum;
  98 }
  99 // Ones complement
 100 static uint8_t calcSumByteAddOnes( uint8_t* bytes, uint8_t len, uint32_t mask) {
 101         return ~calcSumByteAdd(bytes, len, mask);
 102 }
 103
 104 static uint8_t calcSumByteSub( uint8_t* bytes, uint8_t len, uint32_t mask) {
 105     uint8_t sum = 0;
 106     for (uint8_t i = 0; i < len; i++)
 107         sum -= bytes[i];
 108         sum &= mask;
 109     return sum;
 110 }
 111 static uint8_t calcSumByteSubOnes( uint8_t* bytes, uint8_t len, uint32_t mask){
 112         return ~calcSumByteSub(bytes, len, mask);
 113 }
 114 static uint8_t calcSumNibbleSub( uint8_t* bytes, uint8_t len, uint32_t mask) {
 115     uint8_t sum = 0;
 116     for (uint8_t i = 0; i < len; i++) {
 117         sum -= NIBBLE_LOW(bytes[i]);
 118                 sum -= NIBBLE_HIGH(bytes[i]);
 119         }
 120         sum &= mask;
 121     return sum;
 122 }
 123 static uint8_t calcSumNibbleSubOnes( uint8_t* bytes, uint8_t len, uint32_t mask) {
 124         return ~calcSumNibbleSub(bytes, len, mask);
 125 }
 126
 127 int CmdAnalyseLCR(const char *Cmd) {
 128         uint8_t data[50];
 129         char cmdp = param_getchar(Cmd, 0);
 130         if (strlen(Cmd) == 0|| cmdp == 'h' || cmdp == 'H') return usage_analyse_lcr();
 131
 132         int len = 0;
 133         param_gethex_ex(Cmd, 0, data, &len);
 134         if ( len%2 ) return usage_analyse_lcr();
 135         len >>= 1;
 136         uint8_t finalXor = calculateLRC(data, len);
 137         PrintAndLog("Target [%02X] requires final LRC XOR byte value: 0x%02X",data[len-1] ,finalXor);
 138         return 0;
 139 }
 140 int CmdAnalyseCRC(const char *Cmd) {
 141
 142         char cmdp = param_getchar(Cmd, 0);
 143         if (strlen(Cmd) == 0 || cmdp == 'h' || cmdp == 'H') return usage_analyse_crc();
 144
 145         int len = strlen(Cmd);
 146         if ( len & 1 ) return usage_analyse_crc();
 147
 148         // add 1 for null terminator.
 149         uint8_t *data = malloc(len+1);
 150         if ( data == NULL ) return 1;
 151
 152         if ( param_gethex(Cmd, 0, data, len)) {
 153                 free(data);
 154                 return usage_analyse_crc();
 155         }
 156         len >>= 1;
 157
 158         //PrintAndLog("\nTests with '%s' hex bytes", sprint_hex(data, len));
 159
 160         PrintAndLog("\nTests of reflection. Two current methods in source code");
 161         PrintAndLog("   reflect(0x3e23L,3) is %04X == 0x3e26", reflect(0x3e23L,3) );
 162         PrintAndLog("  SwapBits(0x3e23L,3) is %04X == 0x3e26", SwapBits(0x3e23L,3) );
 163         PrintAndLog("  0xB400 == %04X", reflect( (1 << 16 | 0xb400),16) );
 164
 165         //
 166         // Test of CRC16,  '123456789' string.
 167         //
 168         PrintAndLog("\nTests with '123456789' string");
 169         uint8_t dataStr[] = { 0x31,0x32,0x33,0x34,0x35,0x36,0x37,0x38,0x39 };
 170         uint8_t legic8 = CRC8Legic(dataStr, sizeof(dataStr));
 171
 172         PrintAndLog("LEGIC: CRC16: %X", CRC16Legic(dataStr, sizeof(dataStr), legic8));
 173
 174         //these below has been tested OK.
 175         PrintAndLog("Confirmed CRC Implementations");
 176         PrintAndLog("LEGIC: CRC8 : %X (0xC6 expected)", legic8);
 177         PrintAndLog("MAXIM: CRC8 : %X (0xA1 expected)", CRC8Maxim(dataStr, sizeof(dataStr)));
 178         PrintAndLog("DNP  : CRC16: %X (0x82EA expected)", CRC16_DNP(dataStr, sizeof(dataStr)));
 179         PrintAndLog("CCITT: CRC16: %X (0xE5CC expected)", CRC16_CCITT(dataStr, sizeof(dataStr)));
 180
 181         free(data);
 182         return 0;
 183 }
 184 int CmdAnalyseCHKSUM(const char *Cmd){
 185
 186         uint8_t data[50];
 187         uint8_t cmdp = 0;
 188         uint32_t mask = 0xFF;
 189         bool errors = false;
 190         int len = 0;
 191
 192         while(param_getchar(Cmd, cmdp) != 0x00) {
 193                 switch(param_getchar(Cmd, cmdp)) {
 194                 case 'b':
 195                 case 'B':
 196                         param_gethex_ex(Cmd, cmdp+1, data, &len);
 197                         if ( len%2 ) errors = true;
 198                         len >>= 1;
 199                         cmdp += 2;
 200                         break;
 201                 case 'm':
 202                 case 'M':
 203                         mask = param_get32ex(Cmd, cmdp+1, 0, 16);
 204                         cmdp += 2;
 205                         break;
 206                 case 'h':
 207                 case 'H':
 208                         return usage_analyse_checksum();
 209                 default:
 210                         PrintAndLog("Unknown parameter '%c'", param_getchar(Cmd, cmdp));
 211                         errors = true;
 212                         break;
 213                 }
 214                 if(errors) break;
 215         }
 216         //Validations
 217         if(errors) return usage_analyse_checksum();
 218
 219         PrintAndLog("\nByte Add        | 0x%X", calcSumByteAdd(data, len, mask));
 220         PrintAndLog("Nibble Add      | 0x%X", calcSumNibbleAdd(data, len, mask));
 221         PrintAndLog("Crumb Add       | 0x%X", calcSumCrumbAdd(data, len, mask));
 222
 223         PrintAndLog("\nByte Subtract   | 0x%X", calcSumByteSub(data, len, mask));
 224         PrintAndLog("Nibble Subtract | 0x%X", calcSumNibbleSub(data, len, mask));
 225
 226         PrintAndLog("\nCHECKSUM - One's complement");
 227         PrintAndLog("Byte Add        | 0x%X", calcSumByteAddOnes(data, len, mask));
 228         PrintAndLog("Nibble Add      | 0x%X", calcSumNibbleAddOnes(data, len, mask));
 229         PrintAndLog("Crumb Add       | 0x%X", calcSumCrumbAddOnes(data, len, mask));
 230
 231         PrintAndLog("Byte Subtract   | 0x%X", calcSumByteSubOnes(data, len, mask));
 232         PrintAndLog("Nibble Subtract | 0x%X", calcSumNibbleSubOnes(data, len, mask));
 233
 234         return 0;
 235 }
 236
 237 int CmdAnalyseDates(const char *Cmd){
 238         // look for datestamps in a given array of bytes
 239         PrintAndLog("To be implemented. Feel free to contribute!");
 240         return 0;
 241 }
 242
 243 static command_t CommandTable[] = {
 244         {"help",        CmdHelp,            1, "This help"},
 245         {"lcr",         CmdAnalyseLCR,          1, "Generate final byte for XOR LRC"},
 246         {"crc",         CmdAnalyseCRC,          1, "Stub method for CRC evaluations"},
 247         {"chksum",      CmdAnalyseCHKSUM,       1, "Checksum with adding, masking and one's complement"},
 248         {"dates",       CmdAnalyseDates,        1, "Look for datestamps in a given array of bytes"},
 249         {NULL, NULL, 0, NULL}
 250 };
 251
 252 int CmdAnalyse(const char *Cmd) {
 253         clearCommandBuffer();
 254         CmdsParse(CommandTable, Cmd);
 255         return 0;
 256 }
 257
 258 int CmdHelp(const char *Cmd) {
 259         CmdsHelp(CommandTable);
 260         return 0;
 261 }