libnfc 1.4.2
nfc-anticol.c
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00001 /*-
00002  * Public platform independent Near Field Communication (NFC) library examples
00003  * 
00004  * Copyright (C) 2009, Roel Verdult
00005  * 
00006  * Redistribution and use in source and binary forms, with or without
00007  * modification, are permitted provided that the following conditions are met:
00008  *  1) Redistributions of source code must retain the above copyright notice,
00009  *  this list of conditions and the following disclaimer. 
00010  *  2 )Redistributions in binary form must reproduce the above copyright
00011  *  notice, this list of conditions and the following disclaimer in the
00012  *  documentation and/or other materials provided with the distribution.
00013  *
00014  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
00015  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
00016  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
00017  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
00018  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
00019  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
00020  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
00021  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
00022  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
00023  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
00024  * POSSIBILITY OF SUCH DAMAGE.
00025  * 
00026  * Note that this license only applies on the examples, NFC library itself is under LGPL
00027  *
00028  */
00029 
00035 #ifdef HAVE_CONFIG_H
00036 #  include "config.h"
00037 #endif // HAVE_CONFIG_H
00038 
00039 #include <stdio.h>
00040 #include <stdlib.h>
00041 #include <stddef.h>
00042 #include <stdint.h>
00043 #include <stdbool.h>
00044 #include <string.h>
00045 
00046 #include <nfc/nfc.h>
00047 
00048 #include <nfc/nfc-messages.h>
00049 #include "nfc-utils.h"
00050 
00051 #define SAK_FLAG_ATS_SUPPORTED 0x20
00052 
00053 #define MAX_FRAME_LEN 264
00054 
00055 static byte_t abtRx[MAX_FRAME_LEN];
00056 static size_t szRxBits;
00057 static size_t szRx;
00058 static byte_t abtRawUid[12];
00059 static byte_t abtAtqa[2];
00060 static byte_t abtSak;
00061 static size_t szCL = 1;//Always start with Cascade Level 1 (CL1)
00062 static nfc_device_t *pnd;
00063 
00064 bool    quiet_output = false;
00065 
00066 // ISO14443A Anti-Collision Commands
00067 byte_t  abtReqa[1] = { 0x26 };
00068 byte_t  abtSelectAll[2] = { 0x93, 0x20 };
00069 byte_t  abtSelectTag[9] = { 0x93, 0x70, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
00070 byte_t  abtRats[4] = { 0xe0, 0x50, 0x00, 0x00 };
00071 byte_t  abtHalt[4] = { 0x50, 0x00, 0x00, 0x00 };
00072 #define CASCADE_BIT 0x04
00073 
00074 static  bool
00075 transmit_bits (const byte_t * pbtTx, const size_t szTxBits)
00076 {
00077   // Show transmitted command
00078   if (!quiet_output) {
00079     printf ("Sent bits:     ");
00080     print_hex_bits (pbtTx, szTxBits);
00081   }
00082   // Transmit the bit frame command, we don't use the arbitrary parity feature
00083   if (!nfc_initiator_transceive_bits (pnd, pbtTx, szTxBits, NULL, abtRx, &szRxBits, NULL))
00084     return false;
00085 
00086   // Show received answer
00087   if (!quiet_output) {
00088     printf ("Received bits: ");
00089     print_hex_bits (abtRx, szRxBits);
00090   }
00091   // Succesful transfer
00092   return true;
00093 }
00094 
00095 
00096 static  bool
00097 transmit_bytes (const byte_t * pbtTx, const size_t szTx)
00098 {
00099   // Show transmitted command
00100   if (!quiet_output) {
00101     printf ("Sent bits:     ");
00102     print_hex (pbtTx, szTx);
00103   }
00104   // Transmit the command bytes
00105   if (!nfc_initiator_transceive_bytes (pnd, pbtTx, szTx, abtRx, &szRx))
00106     return false;
00107 
00108   // Show received answer
00109   if (!quiet_output) {
00110     printf ("Received bits: ");
00111     print_hex (abtRx, szRx);
00112   }
00113   // Succesful transfer
00114   return true;
00115 }
00116 
00117 static void
00118 print_usage (char *argv[])
00119 {
00120   printf ("Usage: %s [OPTIONS]\n", argv[0]);
00121   printf ("Options:\n");
00122   printf ("\t-h\tHelp. Print this message.\n");
00123   printf ("\t-q\tQuiet mode. Suppress output of READER and EMULATOR data (improves timing).\n");
00124 }
00125 
00126 int
00127 main (int argc, char *argv[])
00128 {
00129   int     arg;
00130 
00131   // Get commandline options
00132   for (arg = 1; arg < argc; arg++) {
00133     if (0 == strcmp (argv[arg], "-h")) {
00134       print_usage (argv);
00135       exit(EXIT_SUCCESS);
00136     } else if (0 == strcmp (argv[arg], "-q")) {
00137       quiet_output = true;
00138     } else {
00139       ERR ("%s is not supported option.", argv[arg]);
00140       print_usage (argv);
00141       exit(EXIT_FAILURE);
00142     }
00143   }
00144 
00145   // Try to open the NFC reader
00146   pnd = nfc_connect (NULL);
00147 
00148   if (!pnd) {
00149     printf ("Error connecting NFC reader\n");
00150     exit(EXIT_FAILURE);
00151   }
00152 
00153   // Initialise NFC device as "initiator"
00154   nfc_initiator_init (pnd);
00155 
00156   // Drop the field for a while
00157   if (!nfc_configure (pnd, NDO_ACTIVATE_FIELD, false)) {
00158     nfc_perror (pnd, "nfc_configure");
00159     exit (EXIT_FAILURE);
00160   }
00161 
00162   // Configure the CRC
00163   if (!nfc_configure (pnd, NDO_HANDLE_CRC, false)) {
00164     nfc_perror (pnd, "nfc_configure");
00165     exit (EXIT_FAILURE);
00166   }
00167   // Configure parity settings
00168   if (!nfc_configure (pnd, NDO_HANDLE_PARITY, true)) {
00169     nfc_perror (pnd, "nfc_configure");
00170     exit (EXIT_FAILURE);
00171   }
00172   // Use raw send/receive methods
00173   if (!nfc_configure (pnd, NDO_EASY_FRAMING, false)) {
00174     nfc_perror (pnd, "nfc_configure");
00175     exit (EXIT_FAILURE);
00176   }
00177   // Disable 14443-4 autoswitching
00178   if (!nfc_configure (pnd, NDO_AUTO_ISO14443_4, false)) {
00179     nfc_perror (pnd, "nfc_configure");
00180     exit (EXIT_FAILURE);
00181   }
00182   // Force 14443-A mode
00183   if (!nfc_configure (pnd, NDO_FORCE_ISO14443_A, true)) {
00184     nfc_perror (pnd, "nfc_configure");
00185     exit (EXIT_FAILURE);
00186   }
00187 
00188   // Enable field so more power consuming cards can power themselves up
00189   if (!nfc_configure (pnd, NDO_ACTIVATE_FIELD, true)) {
00190     nfc_perror (pnd, "nfc_configure");
00191     exit (EXIT_FAILURE);
00192   }
00193 
00194   printf ("Connected to NFC reader: %s\n\n", pnd->acName);
00195 
00196   // Send the 7 bits request command specified in ISO 14443A (0x26)
00197   if (!transmit_bits (abtReqa, 7)) {
00198     printf ("Error: No tag available\n");
00199     nfc_disconnect (pnd);
00200     return 1;
00201   }
00202   memcpy (abtAtqa, abtRx, 2);
00203 
00204   // Anti-collision
00205   transmit_bytes (abtSelectAll, 2);
00206 
00207   // Check answer
00208   if ((abtRx[0] ^ abtRx[1] ^ abtRx[2] ^ abtRx[3] ^ abtRx[4]) != 0) {
00209     printf("WARNING: BCC check failed!\n");
00210   }
00211 
00212   // Save the UID CL1
00213   memcpy (abtRawUid, abtRx, 4);
00214 
00215   //Prepare and send CL1 Select-Command
00216   memcpy (abtSelectTag + 2, abtRx, 5);
00217   iso14443a_crc_append (abtSelectTag, 7);
00218   transmit_bytes (abtSelectTag, 9);
00219   abtSak = abtRx[0];
00220 
00221   // Test if we are dealing with a CL2
00222   if (abtSak & CASCADE_BIT) {
00223     szCL = 2;//or more
00224     // Check answer
00225     if (abtRawUid[0] != 0x88) {
00226       printf("WARNING: Cascade bit set but CT != 0x88!\n");
00227     }
00228   }
00229 
00230   if(szCL == 2) {
00231     // We have to do the anti-collision for cascade level 2
00232 
00233     // Prepare CL2 commands
00234     abtSelectAll[0] = 0x95;
00235 
00236     // Anti-collision
00237     transmit_bytes (abtSelectAll, 2);
00238 
00239     // Check answer
00240     if ((abtRx[0] ^ abtRx[1] ^ abtRx[2] ^ abtRx[3] ^ abtRx[4]) != 0) {
00241       printf("WARNING: BCC check failed!\n");
00242     }
00243 
00244     // Save UID CL2
00245     memcpy (abtRawUid + 4, abtRx, 4);
00246 
00247     // Selection
00248     abtSelectTag[0] = 0x95;
00249     memcpy (abtSelectTag + 2, abtRx, 5);
00250     iso14443a_crc_append (abtSelectTag, 7);
00251     transmit_bytes (abtSelectTag, 9);
00252     abtSak = abtRx[0];
00253 
00254     // Test if we are dealing with a CL3
00255     if (abtSak & CASCADE_BIT) {
00256       szCL = 3;
00257       // Check answer
00258       if (abtRawUid[0] != 0x88) {
00259         printf("WARNING: Cascade bit set but CT != 0x88!\n");
00260       }
00261     }
00262 
00263     if ( szCL == 3) {
00264       // We have to do the anti-collision for cascade level 3
00265 
00266       // Prepare and send CL3 AC-Command
00267       abtSelectAll[0] = 0x97;
00268       transmit_bytes (abtSelectAll, 2);
00269 
00270       // Check answer
00271       if ((abtRx[0] ^ abtRx[1] ^ abtRx[2] ^ abtRx[3] ^ abtRx[4]) != 0) {
00272         printf("WARNING: BCC check failed!\n");
00273       }
00274 
00275       // Save UID CL3
00276       memcpy (abtRawUid + 8, abtRx, 4);
00277 
00278       // Prepare and send final Select-Command
00279       abtSelectTag[0] = 0x97;
00280       memcpy (abtSelectTag + 2, abtRx, 5);
00281       iso14443a_crc_append (abtSelectTag, 7);
00282       transmit_bytes (abtSelectTag, 9);
00283       abtSak = abtRx[0];
00284     }
00285   }
00286 
00287   // Request ATS, this only applies to tags that support ISO 14443A-4
00288   if (abtRx[0] & SAK_FLAG_ATS_SUPPORTED) {
00289     iso14443a_crc_append(abtRats, 2);
00290     transmit_bytes (abtRats, 4);
00291   }
00292 
00293   // Done, halt the tag now
00294   iso14443a_crc_append(abtHalt, 2);
00295   transmit_bytes (abtHalt, 4);
00296 
00297   printf ("\nFound tag with\n UID: ");
00298   switch (szCL) {
00299     case 1:
00300       printf ("%02x%02x%02x%02x", abtRawUid[0], abtRawUid[1], abtRawUid[2], abtRawUid[3]);
00301     break;
00302     case 2:
00303       printf ("%02x%02x%02x", abtRawUid[1], abtRawUid[2], abtRawUid[3]);
00304       printf ("%02x%02x%02x%02x", abtRawUid[4], abtRawUid[5], abtRawUid[6], abtRawUid[7]);
00305     break;
00306     case 3:
00307       printf ("%02x%02x%02x", abtRawUid[1], abtRawUid[2], abtRawUid[3]);
00308       printf ("%02x%02x%02x", abtRawUid[5], abtRawUid[6], abtRawUid[7]);
00309       printf ("%02x%02x%02x%02x", abtRawUid[8], abtRawUid[9], abtRawUid[10], abtRawUid[11]);
00310     break;
00311   }
00312   printf("\n");
00313   printf("ATQA: %02x%02x\n SAK: %02x\n", abtAtqa[1], abtAtqa[0], abtSak);
00314 
00315   nfc_disconnect (pnd);
00316   return 0;
00317 }