client/cmdhflegic.c

   1 //-----------------------------------------------------------------------------
   2 // Copyright (C) 2010 iZsh <izsh at fail0verflow.com>
   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 // High frequency Legic commands
   9 //-----------------------------------------------------------------------------
  10
  11 #include <stdio.h>
  12 #include <string.h>
  13 #include "proxmark3.h"
  14 #include "data.h"
  15 #include "ui.h"
  16 #include "cmdparser.h"
  17 #include "cmdhflegic.h"
  18 #include "cmdmain.h"
  19 #include "util.h"
  20 static int CmdHelp(const char *Cmd);
  21
  22 static command_t CommandTable[] =
  23 {
  24   {"help",        CmdHelp,        1, "This help"},
  25   {"decode",      CmdLegicDecode, 0, "Display deobfuscated and decoded LEGIC RF tag data (use after hf legic reader)"},
  26   {"reader",      CmdLegicRFRead, 0, "[offset [length]] -- read bytes from a LEGIC card"},
  27   {"save",        CmdLegicSave,   0, "<filename> [<length>] -- Store samples"},
  28   {"load",        CmdLegicLoad,   0, "<filename> -- Restore samples"},
  29   {"sim",         CmdLegicRfSim,  0, "[phase drift [frame drift [req/resp drift]]] Start tag simulator (use after load or read)"},
  30   {"write",       CmdLegicRfWrite,0, "<offset> <length> -- Write sample buffer (user after load or read)"},
  31   {"fill",        CmdLegicRfFill, 0, "<offset> <length> <value> -- Fill/Write tag with constant value"},
  32   {NULL, NULL, 0, NULL}
  33 };
  34
  35 int CmdHFLegic(const char *Cmd)
  36 {
  37   CmdsParse(CommandTable, Cmd);
  38   return 0;
  39 }
  40
  41 int CmdHelp(const char *Cmd)
  42 {
  43   CmdsHelp(CommandTable);
  44   return 0;
  45 }
  46
  47 /*
  48  *  Output BigBuf and deobfuscate LEGIC RF tag data.
  49  *   This is based on information given in the talk held
  50  *  by Henryk Ploetz and Karsten Nohl at 26c3
  51  */
  52 int CmdLegicDecode(const char *Cmd)
  53 {
  54   int i, j, k, n;
  55   int segment_len = 0;
  56   int segment_flag = 0;
  57   int stamp_len = 0;
  58   int crc = 0;
  59   int wrp = 0;
  60   int wrc = 0;
  61   uint8_t data_buf[1024]; // receiver buffer
  62   char out_string[3076]; // just use big buffer - bad practice
  63   char token_type[4];
  64
  65   // copy data from proxmark into buffer
  66    GetFromBigBuf(data_buf,sizeof(data_buf),0);
  67    WaitForResponse(CMD_ACK,NULL);
  68
  69   // Output CDF System area (9 bytes) plus remaining header area (12 bytes)
  70
  71   PrintAndLog("\nCDF: System Area");
  72
  73   PrintAndLog("MCD: %02x, MSN: %02x %02x %02x, MCC: %02x",
  74     data_buf[0],
  75     data_buf[1],
  76     data_buf[2],
  77     data_buf[3],
  78     data_buf[4]
  79   );
  80
  81   crc = data_buf[4];
  82
  83   switch (data_buf[5]&0x7f) {
  84     case 0x00 ... 0x2f:
  85       strncpy(token_type, "IAM",sizeof(token_type));
  86       break;
  87     case 0x30 ... 0x6f:
  88       strcpy(token_type, "SAM");
  89       break;
  90     case 0x70 ... 0x7f:
  91       strcpy(token_type, "GAM");
  92       break;
  93     default:
  94       strcpy(token_type, "???");
  95       break;
  96   }
  97
  98   stamp_len = 0xfc - data_buf[6];
  99
 100   PrintAndLog("DCF: %02x %02x, Token_Type=%s (OLE=%01u), Stamp_len=%02u",
 101     data_buf[5],
 102     data_buf[6],
 103     token_type,
 104     (data_buf[5]&0x80)>>7,
 105     stamp_len
 106   );
 107
 108   PrintAndLog("WRP=%02u, WRC=%01u, RD=%01u, raw=%02x, SSC=%02x",
 109     data_buf[7]&0x0f,
 110     (data_buf[7]&0x70)>>4,
 111     (data_buf[7]&0x80)>>7,
 112     data_buf[7],
 113     data_buf[8]
 114   );
 115
 116   PrintAndLog("Remaining Header Area");
 117
 118   PrintAndLog("%02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x",
 119       data_buf[9],
 120     data_buf[10],
 121     data_buf[11],
 122     data_buf[12],
 123     data_buf[13],
 124     data_buf[14],
 125     data_buf[15],
 126     data_buf[16],
 127     data_buf[17],
 128     data_buf[18],
 129     data_buf[19],
 130     data_buf[20],
 131     data_buf[21]
 132   );
 133
 134   PrintAndLog("\nADF: User Area");
 135
 136   i = 22;
 137   for (n=0; n<64; n++) {
 138     segment_len = ((data_buf[i+1]^crc)&0x0f) * 256 + (data_buf[i]^crc);
 139     segment_flag = ((data_buf[i+1]^crc)&0xf0)>>4;
 140
 141     wrp = (data_buf[i+2]^crc);
 142     wrc = ((data_buf[i+3]^crc)&0x70)>>4;
 143
 144      PrintAndLog("Segment %02u: raw header=%02x %02x %02x %02x, flag=%01x (valid=%01u, last=%01u), len=%04u, WRP=%02u, WRC=%02u, RD=%01u, CRC=%02x",
 145       n,
 146       data_buf[i]^crc,
 147       data_buf[i+1]^crc,
 148       data_buf[i+2]^crc,
 149       data_buf[i+3]^crc,
 150       segment_flag,
 151       (segment_flag&0x4)>>2,
 152       (segment_flag&0x8)>>3,
 153       segment_len,
 154       wrp,
 155       wrc,
 156       ((data_buf[i+3]^crc)&0x80)>>7,
 157       (data_buf[i+4]^crc)
 158     );
 159
 160     i+=5;
 161
 162     if (wrc>0) {
 163       PrintAndLog("WRC protected area:");
 164       for (k=0, j=0; k < wrc && j<(sizeof(out_string)-3); k++, i++, j += 3) {
 165         sprintf(&out_string[j], "%02x", (data_buf[i]^crc));
 166         out_string[j+2] = ' ';
 167       };
 168
 169       out_string[j] = '\0';
 170
 171       PrintAndLog("%s", out_string);
 172     }
 173
 174     if (wrp>wrc) {
 175       PrintAndLog("Remaining write protected area:");
 176
 177       for (k=0, j=0; k < (wrp-wrc) && j<(sizeof(out_string)-3); k++, i++, j += 3) {
 178         sprintf(&out_string[j], "%02x", (data_buf[i]^crc));
 179         out_string[j+2] = ' ';
 180       };
 181
 182       out_string[j] = '\0';
 183
 184       PrintAndLog("%s", out_string);
 185       if((wrp-wrc) == 8) {
 186         sprintf(out_string,"Card ID: %2X%02X%02X",data_buf[i-4]^crc,data_buf[i-3]^crc,data_buf[i-2]^crc);
 187         PrintAndLog("%s", out_string);
 188       }
 189     }
 190
 191     PrintAndLog("Remaining segment payload:");
 192     for (k=0, j=0; k < (segment_len - wrp - 5) && j<(sizeof(out_string)-3); k++, i++, j += 3) {
 193       sprintf(&out_string[j], "%02x", (data_buf[i]^crc));
 194       out_string[j+2] = ' ';
 195     };
 196
 197     out_string[j] = '\0';
 198
 199     PrintAndLog("%s", out_string);
 200
 201     // end with last segment
 202     if (segment_flag & 0x8)
 203       return 0;
 204   };
 205   return 0;
 206 }
 207
 208 int CmdLegicRFRead(const char *Cmd)
 209 {
 210   int byte_count=0,offset=0;
 211   sscanf(Cmd, "%i %i", &offset, &byte_count);
 212   if(byte_count == 0) byte_count = -1;
 213   if(byte_count + offset > 1024) byte_count = 1024 - offset;
 214   UsbCommand c={CMD_READER_LEGIC_RF, {offset, byte_count, 0}};
 215   SendCommand(&c);
 216   return 0;
 217 }
 218
 219 int CmdLegicLoad(const char *Cmd)
 220 {
 221         char filename[FILE_PATH_SIZE] = {0x00};
 222         int len = 0;
 223
 224         if (param_getchar(Cmd, 0) == 'h' || param_getchar(Cmd, 0)== 0x00) {
 225                 PrintAndLog("It loads datasamples from the file `filename`");
 226                 PrintAndLog("Usage:  hf legic load <file name>");
 227                 PrintAndLog(" sample: hf legic load filename");
 228                 return 0;
 229         }
 230
 231         len = strlen(Cmd);
 232         if (len > FILE_PATH_SIZE) {
 233                 PrintAndLog("Filepath too long (was %s bytes), max allowed is %s ", len, FILE_PATH_SIZE);
 234                 return 0;
 235         }
 236         memcpy(filename, Cmd, len);
 237
 238     FILE *f = fopen(filename, "r");
 239     if(!f) {
 240         PrintAndLog("couldn't open '%s'", Cmd);
 241         return -1;
 242     }
 243     char line[80]; int offset = 0; unsigned int data[8];
 244     while(fgets(line, sizeof(line), f)) {
 245         int res = sscanf(line, "%x %x %x %x %x %x %x %x",
 246             &data[0], &data[1], &data[2], &data[3],
 247             &data[4], &data[5], &data[6], &data[7]);
 248         if(res != 8) {
 249           PrintAndLog("Error: could not read samples");
 250           fclose(f);
 251           return -1;
 252         }
 253         UsbCommand c={CMD_DOWNLOADED_SIM_SAMPLES_125K, {offset, 0, 0}};
 254         int j; for(j = 0; j < 8; j++) {
 255             c.d.asBytes[j] = data[j];
 256         }
 257         SendCommand(&c);
 258         WaitForResponse(CMD_ACK, NULL);
 259         offset += 8;
 260     }
 261     fclose(f);
 262     PrintAndLog("loaded %u samples", offset);
 263     return 0;
 264 }
 265
 266 int CmdLegicSave(const char *Cmd)
 267 {
 268   int requested = 1024;
 269   int offset = 0;
 270   int delivered = 0;
 271   char filename[FILE_PATH_SIZE];
 272   uint8_t got[1024];
 273
 274   sscanf(Cmd, " %s %i %i", filename, &requested, &offset);
 275
 276   /* If no length given save entire legic read buffer */
 277   /* round up to nearest 8 bytes so the saved data can be used with legicload */
 278   if (requested == 0) {
 279     requested = 1024;
 280   }
 281   if (requested % 8 != 0) {
 282     int remainder = requested % 8;
 283     requested = requested + 8 - remainder;
 284   }
 285   if (offset + requested > sizeof(got)) {
 286     PrintAndLog("Tried to read past end of buffer, <bytes> + <offset> > 1024");
 287     return 0;
 288   }
 289
 290   FILE *f = fopen(filename, "w");
 291   if(!f) {
 292     PrintAndLog("couldn't open '%s'", Cmd+1);
 293     return -1;
 294   }
 295
 296   GetFromBigBuf(got,requested,offset);
 297   WaitForResponse(CMD_ACK,NULL);
 298
 299   for (int j = 0; j < requested; j += 8) {
 300     fprintf(f, "%02x %02x %02x %02x %02x %02x %02x %02x\n",
 301       got[j+0],
 302       got[j+1],
 303       got[j+2],
 304       got[j+3],
 305       got[j+4],
 306       got[j+5],
 307       got[j+6],
 308       got[j+7]
 309     );
 310     delivered += 8;
 311     if (delivered >= requested)
 312       break;
 313   }
 314
 315   fclose(f);
 316   PrintAndLog("saved %u samples", delivered);
 317   return 0;
 318 }
 319
 320 int CmdLegicRfSim(const char *Cmd)
 321 {
 322    UsbCommand c={CMD_SIMULATE_TAG_LEGIC_RF};
 323    c.arg[0] = 6;
 324    c.arg[1] = 3;
 325    c.arg[2] = 0;
 326    sscanf(Cmd, " %"lli" %"lli" %"lli, &c.arg[0], &c.arg[1], &c.arg[2]);
 327    SendCommand(&c);
 328    return 0;
 329 }
 330
 331 int CmdLegicRfWrite(const char *Cmd)
 332 {
 333     UsbCommand c={CMD_WRITER_LEGIC_RF};
 334     int res = sscanf(Cmd, " 0x%"llx" 0x%"llx, &c.arg[0], &c.arg[1]);
 335         if(res != 2) {
 336                 PrintAndLog("Please specify the offset and length as two hex strings");
 337         return -1;
 338     }
 339     SendCommand(&c);
 340     return 0;
 341 }
 342
 343 int CmdLegicRfFill(const char *Cmd)
 344 {
 345     UsbCommand cmd ={CMD_WRITER_LEGIC_RF};
 346     int res = sscanf(Cmd, " 0x%"llx" 0x%"llx" 0x%"llx, &cmd.arg[0], &cmd.arg[1], &cmd.arg[2]);
 347     if(res != 3) {
 348         PrintAndLog("Please specify the offset, length and value as two hex strings");
 349         return -1;
 350     }
 351
 352     int i;
 353     UsbCommand c={CMD_DOWNLOADED_SIM_SAMPLES_125K, {0, 0, 0}};
 354     for(i = 0; i < 48; i++) {
 355       c.d.asBytes[i] = cmd.arg[2];
 356     }
 357     for(i = 0; i < 22; i++) {
 358       c.arg[0] = i*48;
 359       SendCommand(&c);
 360       WaitForResponse(CMD_ACK,NULL);
 361     }
 362     SendCommand(&cmd);
 363     return 0;
 364  }
 365