+
+/*
+ * Output BigBuf and deobfuscate LEGIC RF tag data.
+ * This is based on information given in the talk held
+ * by Henryk Ploetz and Karsten Nohl at 26c3
+ */
+int CmdLegicDecode(const char *Cmd)
+{
+ int i, j, k, n;
+ int segment_len = 0;
+ int segment_flag = 0;
+ int stamp_len = 0;
+ int crc = 0;
+ int wrp = 0;
+ int wrc = 0;
+ uint8_t data_buf[1052]; // receiver buffer
+ char out_string[3076]; // just use big buffer - bad practice
+ char token_type[4];
+
+ // copy data from proxmark into buffer
+ GetFromBigBuf(data_buf,sizeof(data_buf),0);
+ WaitForResponse(CMD_ACK,NULL);
+
+ // Output CDF System area (9 bytes) plus remaining header area (12 bytes)
+
+ PrintAndLog("\nCDF: System Area");
+
+ PrintAndLog("MCD: %02x, MSN: %02x %02x %02x, MCC: %02x",
+ data_buf[0],
+ data_buf[1],
+ data_buf[2],
+ data_buf[3],
+ data_buf[4]
+ );
+
+ crc = data_buf[4];
+
+ switch (data_buf[5]&0x7f) {
+ case 0x00 ... 0x2f:
+ strncpy(token_type, "IAM",sizeof(token_type));
+ break;
+ case 0x30 ... 0x6f:
+ strcpy(token_type, "SAM");
+ break;
+ case 0x70 ... 0x7f:
+ strcpy(token_type, "GAM");
+ break;
+ default:
+ strcpy(token_type, "???");
+ break;
+ }
+
+ stamp_len = 0xfc - data_buf[6];
+
+ PrintAndLog("DCF: %02x %02x, Token_Type=%s (OLE=%01u), Stamp_len=%02u",
+ data_buf[5],
+ data_buf[6],
+ token_type,
+ (data_buf[5]&0x80)>>7,
+ stamp_len
+ );
+
+ PrintAndLog("WRP=%02u, WRC=%01u, RD=%01u, raw=%02x, SSC=%02x",
+ data_buf[7]&0x0f,
+ (data_buf[7]&0x70)>>4,
+ (data_buf[7]&0x80)>>7,
+ data_buf[7],
+ data_buf[8]
+ );
+
+ PrintAndLog("Remaining Header Area");
+
+ PrintAndLog("%02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x",
+ data_buf[9],
+ data_buf[10],
+ data_buf[11],
+ data_buf[12],
+ data_buf[13],
+ data_buf[14],
+ data_buf[15],
+ data_buf[16],
+ data_buf[17],
+ data_buf[18],
+ data_buf[19],
+ data_buf[20],
+ data_buf[21]
+ );
+
+ PrintAndLog("\nADF: User Area");
+
+ i = 22;
+ for (n=0; n<64; n++) {
+ segment_len = ((data_buf[i+1]^crc)&0x0f) * 256 + (data_buf[i]^crc);
+ segment_flag = ((data_buf[i+1]^crc)&0xf0)>>4;
+
+ wrp = (data_buf[i+2]^crc);
+ wrc = ((data_buf[i+3]^crc)&0x70)>>4;
+
+ 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",
+ n,
+ data_buf[i]^crc,
+ data_buf[i+1]^crc,
+ data_buf[i+2]^crc,
+ data_buf[i+3]^crc,
+ segment_flag,
+ (segment_flag&0x4)>>2,
+ (segment_flag&0x8)>>3,
+ segment_len,
+ wrp,
+ wrc,
+ ((data_buf[i+3]^crc)&0x80)>>7,
+ (data_buf[i+4]^crc)
+ );
+
+ i+=5;
+
+ if (wrc>0) {
+ PrintAndLog("WRC protected area:");
+ for (k=0, j=0; k < wrc && j<(sizeof(out_string)-3); k++, i++, j += 3) {
+ sprintf(&out_string[j], "%02x", (data_buf[i]^crc));
+ out_string[j+2] = ' ';
+ };
+
+ out_string[j] = '\0';
+
+ PrintAndLog("%s", out_string);
+ }
+
+ if (wrp>wrc) {
+ PrintAndLog("Remaining write protected area:");
+
+ for (k=0, j=0; k < (wrp-wrc) && j<(sizeof(out_string)-3); k++, i++, j += 3) {
+ sprintf(&out_string[j], "%02x", (data_buf[i]^crc));
+ out_string[j+2] = ' ';
+ };
+
+ out_string[j] = '\0';
+
+ PrintAndLog("%s", out_string);
+ if((wrp-wrc) == 8) {
+ sprintf(out_string,"Card ID: %2X%02X%02X",data_buf[i-4]^crc,data_buf[i-3]^crc,data_buf[i-2]^crc);
+ PrintAndLog("%s", out_string);
+ }
+ }
+
+ PrintAndLog("Remaining segment payload:");
+ for (k=0, j=0; k < (segment_len - wrp - 5) && j<(sizeof(out_string)-3); k++, i++, j += 3) {
+ sprintf(&out_string[j], "%02x", (data_buf[i]^crc));
+ out_string[j+2] = ' ';
+ };
+
+ out_string[j] = '\0';
+
+ PrintAndLog("%s", out_string);
+
+ // end with last segment
+ if (segment_flag & 0x8)
+ return 0;
+ };
+ return 0;
+}
+
+int CmdLegicRFRead(const char *Cmd)
+{
+ int byte_count=0,offset=0;
+ sscanf(Cmd, "%i %i", &offset, &byte_count);
+ if(byte_count == 0) byte_count = -1;
+ if(byte_count + offset > 1024) byte_count = 1024 - offset;
+ UsbCommand c={CMD_READER_LEGIC_RF, {offset, byte_count, 0}};
+ SendCommand(&c);
+ return 0;
+}
+
+int CmdLegicLoad(const char *Cmd)
+{
+ char filename[FILE_PATH_SIZE] = {0x00};
+ int len = 0;
+
+ if (param_getchar(Cmd, 0) == 'h' || param_getchar(Cmd, 0)== 0x00) {
+ PrintAndLog("It loads datasamples from the file `filename`");
+ PrintAndLog("Usage: hf legic load <file name>");
+ PrintAndLog(" sample: hf legic load filename");
+ return 0;
+ }
+
+ len = strlen(Cmd);
+ if (len > FILE_PATH_SIZE) {
+ PrintAndLog("Filepath too long (was %s bytes), max allowed is %s ", len, FILE_PATH_SIZE);
+ return 0;
+ }
+ memcpy(filename, Cmd, len);
+
+ FILE *f = fopen(filename, "r");
+ if(!f) {
+ PrintAndLog("couldn't open '%s'", Cmd);
+ return -1;
+ }
+ char line[80]; int offset = 0; unsigned int data[8];
+ while(fgets(line, sizeof(line), f)) {
+ int res = sscanf(line, "%x %x %x %x %x %x %x %x",
+ &data[0], &data[1], &data[2], &data[3],
+ &data[4], &data[5], &data[6], &data[7]);
+ if(res != 8) {
+ PrintAndLog("Error: could not read samples");
+ fclose(f);
+ return -1;
+ }
+ UsbCommand c={CMD_DOWNLOADED_SIM_SAMPLES_125K, {offset, 0, 0}};
+ int j; for(j = 0; j < 8; j++) {
+ c.d.asBytes[j] = data[j];
+ }
+ SendCommand(&c);
+ WaitForResponse(CMD_ACK, NULL);
+ offset += 8;
+ }
+ fclose(f);
+ PrintAndLog("loaded %u samples", offset);
+ return 0;
+}
+
+int CmdLegicSave(const char *Cmd)
+{
+ int requested = 1024;
+ int offset = 0;
+ int delivered = 0;
+ char filename[FILE_PATH_SIZE];
+ uint8_t got[1024];
+
+ sscanf(Cmd, " %s %i %i", filename, &requested, &offset);
+
+ /* If no length given save entire legic read buffer */
+ /* round up to nearest 8 bytes so the saved data can be used with legicload */
+ if (requested == 0) {
+ requested = 1024;
+ }
+ if (requested % 8 != 0) {
+ int remainder = requested % 8;
+ requested = requested + 8 - remainder;
+ }
+ if (offset + requested > sizeof(got)) {
+ PrintAndLog("Tried to read past end of buffer, <bytes> + <offset> > 1024");
+ return 0;
+ }
+
+ FILE *f = fopen(filename, "w");
+ if(!f) {
+ PrintAndLog("couldn't open '%s'", Cmd+1);
+ return -1;
+ }
+
+ GetFromBigBuf(got,requested,offset);
+ WaitForResponse(CMD_ACK,NULL);
+
+ for (int j = 0; j < requested; j += 8) {
+ fprintf(f, "%02x %02x %02x %02x %02x %02x %02x %02x\n",
+ got[j+0],
+ got[j+1],
+ got[j+2],
+ got[j+3],
+ got[j+4],
+ got[j+5],
+ got[j+6],
+ got[j+7]
+ );
+ delivered += 8;
+ if (delivered >= requested)
+ break;
+ }
+
+ fclose(f);
+ PrintAndLog("saved %u samples", delivered);
+ return 0;
+}
+
+int CmdLegicRfSim(const char *Cmd)
+{
+ UsbCommand c={CMD_SIMULATE_TAG_LEGIC_RF};
+ c.arg[0] = 6;
+ c.arg[1] = 3;
+ c.arg[2] = 0;
+ sscanf(Cmd, " %"lli" %"lli" %"lli, &c.arg[0], &c.arg[1], &c.arg[2]);
+ SendCommand(&c);
+ return 0;
+}
+
+int CmdLegicRfWrite(const char *Cmd)
+{
+ UsbCommand c={CMD_WRITER_LEGIC_RF};
+ int res = sscanf(Cmd, " 0x%"llx" 0x%"llx, &c.arg[0], &c.arg[1]);
+ if(res != 2) {
+ PrintAndLog("Please specify the offset and length as two hex strings");
+ return -1;
+ }
+ SendCommand(&c);
+ return 0;
+}
+
+int CmdLegicRfFill(const char *Cmd)
+{
+ UsbCommand cmd ={CMD_WRITER_LEGIC_RF};
+ int res = sscanf(Cmd, " 0x%"llx" 0x%"llx" 0x%"llx, &cmd.arg[0], &cmd.arg[1], &cmd.arg[2]);
+ if(res != 3) {
+ PrintAndLog("Please specify the offset, length and value as two hex strings");
+ return -1;
+ }
+
+ int i;
+ UsbCommand c={CMD_DOWNLOADED_SIM_SAMPLES_125K, {0, 0, 0}};
+ for(i = 0; i < 48; i++) {
+ c.d.asBytes[i] = cmd.arg[2];
+ }
+ for(i = 0; i < 22; i++) {
+ c.arg[0] = i*48;
+ SendCommand(&c);
+ WaitForResponse(CMD_ACK,NULL);
+ }
+ SendCommand(&cmd);
+ return 0;
+ }
+