git.rot13.org Git - librfid/blob - src/rfid_layer2_iso14443b.c

   1 /* ISO 14443-3 B anticollision implementation
   2  *
   3  * (C) 2005-2006 by Harald Welte <laforge@gnumonks.org>
   4  *
   5  */
   6
   7 /*
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License version 2
  10  *  as published by the Free Software Foundation
  11  *
  12  *  This program is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *  GNU General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU General Public License
  18  *  along with this program; if not, write to the Free Software
  19  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21
  22 #include <stdlib.h>
  23 #include <unistd.h>
  24 #include <string.h>
  25 #include <errno.h>
  26
  27 #include <librfid/rfid.h>
  28 #include <librfid/rfid_layer2.h>
  29 #include <librfid/rfid_reader.h>
  30 #include <librfid/rfid_layer2_iso14443b.h>
  31 #include <librfid/rfid_protocol.h>
  32
  33 #include "rfid_iso14443_common.h"
  34
  35 #define ATQB_TIMEOUT    ((256*10e6/ISO14443_FREQ_SUBCARRIER)            \
  36                          +(200*10e6/ISO14443_FREQ_SUBCARRIER))
  37
  38 #undef ATQB_TIMEOUT
  39 #define ATQB_TIMEOUT    1
  40
  41 static inline int
  42 fwi_to_fwt(struct rfid_layer2_handle *h, unsigned int *fwt, unsigned int fwi)
  43 {
  44         unsigned int multiplier, tmp;
  45
  46         /* 15 is RFU */
  47         if (fwi > 14)
  48                 return -1;
  49
  50         /* According to ISO 14443-3:200(E), Chapter 7.9.4.3, the forumala is
  51          * (256 * 16 / fC) * 2^fwi We avoid floating point computations by
  52          * shifting everything into the microsecond range.  In integer
  53          * calculations 1000000*256*16/13560000 evaluates to 302 (instead of
  54          * 302.064897), which provides sufficient precision, IMHO.  The max
  55          * result is 302 * 16384 (4947968), which fits well within the 31/32
  56          * bit range of an integer */
  57
  58         multiplier = 1 << fwi;          /* 2 to the power of fwi */
  59
  60         tmp = (unsigned int) 1000000 * 256 * 16;
  61
  62         return (tmp / h->rh->ah->asic->fc) * multiplier;
  63 }
  64
  65 static int
  66 parse_atqb(struct rfid_layer2_handle *h, struct iso14443b_atqb *atqb)
  67 {
  68         int ret;
  69
  70         if (atqb->fifty != 0x50)
  71                 return -1;
  72
  73         if (atqb->protocol_info.fo & 0x01)
  74                 h->priv.iso14443b.flags |= ISO14443B_CID_SUPPORTED;
  75         if (atqb->protocol_info.fo & 0x02)
  76                 h->priv.iso14443b.flags |= ISO14443B_NAD_SUPPORTED;
  77
  78         ret = fwi_to_fwt(h, &h->priv.iso14443b.fwt, atqb->protocol_info.fwi);
  79         if (ret < 0) {
  80                 DEBUGP("invalid fwi %u\n", atqb->protocol_info.fwi);
  81                 return ret;
  82         }
  83
  84         if (atqb->protocol_info.protocol_type == 0x1) {
  85                 DEBUGP("we have a T=CL compliant PICC\n");
  86                 h->priv.iso14443b.tcl_capable = 1;
  87                 h->proto_supported = (1 << RFID_PROTOCOL_TCL);
  88         } else {
  89                 DEBUGP("we have a T!=CL PICC\n");
  90                 h->priv.iso14443b.tcl_capable = 0;
  91                 /* FIXME: what protocols do we support? */
  92         }
  93
  94         iso14443_fsdi_to_fsd(&h->priv.iso14443b.fsc,
  95                              atqb->protocol_info.max_frame_size);
  96
  97         /* FIXME: speed capability */
  98
  99         memcpy(h->uid, atqb->pupi, sizeof(atqb->pupi));
 100         h->uid_len = sizeof(atqb->pupi);
 101
 102         return 0;
 103 }
 104
 105 static int
 106 send_reqb(struct rfid_layer2_handle *h, unsigned char afi,
 107           unsigned int is_wup, unsigned int num_initial_slots)
 108 {
 109         int ret;
 110         unsigned char reqb[3];
 111         struct iso14443b_atqb atqb;
 112         unsigned int atqb_len = sizeof(atqb);
 113         unsigned int num_slot_idx = num_initial_slots;
 114
 115         reqb[0] = 0x05;
 116         reqb[1] = afi;
 117
 118         for (num_slot_idx = num_initial_slots; num_slot_idx <= 4;
 119              num_slot_idx++) {
 120                 reqb[2] = num_slot_idx & 0x07;
 121                 if (is_wup)
 122                         reqb[2] |= 0x08;
 123
 124                 ret = h->rh->reader->transceive(h->rh, RFID_14443B_FRAME_REGULAR,
 125                                                 reqb, sizeof(reqb),
 126                                                  (unsigned char *)&atqb,
 127                                                  &atqb_len, ATQB_TIMEOUT, 0);
 128                 h->priv.iso14443b.state = ISO14443B_STATE_REQB_SENT;
 129                 if (ret < 0) {
 130                         DEBUGP("error during transceive of REQB/WUBP\n");
 131                         continue;
 132                 }
 133
 134                 /* FIXME: send N-1 slot marker frames */
 135
 136                 if (atqb_len != sizeof(atqb)) {
 137                         DEBUGP("error: atqb_len = %u instead of %Zu\n",
 138                                 atqb_len, sizeof(atqb));
 139                         continue;
 140                 }
 141
 142                 /* FIXME: how to detect a collission at 14443B ?  I guess we
 143                  * can only rely on the CRC checking (CRCErr in ErrorFlag
 144                  * register?) */
 145
 146                 if (parse_atqb(h, &atqb) >= 0) {
 147                         h->priv.iso14443b.state = ISO14443B_STATE_ATQB_RCVD;
 148                         return 0;
 149                 }
 150         }
 151
 152         return -1;
 153 }
 154
 155 static inline unsigned int mbli_to_mbl(struct rfid_layer2_handle *h,
 156                                         unsigned int mbli)
 157 {
 158         return (h->priv.iso14443b.fsc * 2 ^ (mbli-1));
 159 }
 160
 161 static int
 162 transceive_attrib(struct rfid_layer2_handle *h, const unsigned char *inf,
 163             unsigned int inf_len, unsigned char *rx_data, unsigned int *rx_len)
 164 {
 165         struct {
 166                 struct iso14443b_attrib_hdr attrib;
 167                 char buf[256-3];
 168         } _attrib_buf;
 169
 170         struct iso14443b_attrib_hdr *attrib = &_attrib_buf.attrib;
 171         unsigned char rx_buf[256];
 172         unsigned char fsdi;
 173         int ret = 0;
 174
 175         DEBUGP("fsd is %u\n", h->priv.iso14443b.fsd);
 176         if (rx_len >= rx_len-1) {
 177                 perror("rx_len too large\n");
 178                 goto out_attrib;
 179         }
 180
 181         /* initialize attrib frame */
 182         memset(&_attrib_buf, 0, sizeof(_attrib_buf));
 183         if (inf_len)
 184                 memcpy((unsigned char *)attrib+sizeof(*attrib), inf, inf_len);
 185
 186         attrib->one_d = 0x1d;
 187         memcpy(attrib->identifier, h->uid, 4);
 188
 189         /* FIXME: do we want to change TR0/TR1 from its default ? */
 190         /* FIXME: do we want to change SOF/EOF from its default ? */
 191
 192         ret = iso14443_fsd_to_fsdi(&fsdi, h->priv.iso14443b.fsd);
 193         if (ret < 0) {
 194                 DEBUGP("unable to map FSD(%u) to FSDI\n",
 195                         h->priv.iso14443b.fsd);
 196                 goto out_rx;
 197         }
 198         attrib->param2.fsdi = fsdi;
 199
 200         /* FIXME: spd_in / spd_out */
 201         if (h->priv.iso14443b.tcl_capable == 1)
 202                 attrib->param3.protocol_type = 0x1;
 203
 204         attrib->param4.cid = h->priv.iso14443b.cid & 0xf;
 205
 206         *rx_len = *rx_len + 1;
 207         ret = h->rh->reader->transceive(h->rh, RFID_14443B_FRAME_REGULAR,
 208                                         (unsigned char *) attrib,
 209                                         sizeof(*attrib)+inf_len,
 210                                         rx_buf, rx_len, h->priv.iso14443b.fwt,
 211                                         0);
 212         h->priv.iso14443b.state = ISO14443B_STATE_ATTRIB_SENT;
 213         if (ret < 0) {
 214                 DEBUGP("transceive problem\n");
 215                 goto out_rx;
 216         }
 217
 218         if ((rx_buf[0] & 0x0f) != h->priv.iso14443b.cid) {
 219                 DEBUGP("ATTRIB response with invalid CID %u (should be %u)\n",
 220                         rx_buf[0] & 0x0f, h->priv.iso14443b.cid);
 221                 ret = -1;
 222                 goto out_rx;
 223         }
 224
 225         h->priv.iso14443b.state = ISO14443B_STATE_SELECTED;
 226
 227         h->priv.iso14443b.mbl = mbli_to_mbl(h, (rx_data[0] & 0xf0) >> 4);
 228
 229         *rx_len = *rx_len - 1;
 230         memcpy(rx_data, rx_buf+1, *rx_len);
 231
 232 out_rx:
 233         free(rx_buf);
 234 out_attrib:
 235
 236         return ret;
 237 }
 238
 239 static int
 240 iso14443b_hltb(struct rfid_layer2_handle *h)
 241 {
 242         int ret;
 243         unsigned char hltb[5];
 244         unsigned char hltb_resp[1];
 245         unsigned int hltb_len = 1;
 246
 247         hltb[0] = 0x50;
 248         memcpy(hltb+1, h->uid, 4);
 249
 250         ret = h->rh->reader->transceive(h->rh, RFID_14443B_FRAME_REGULAR,
 251                                         hltb, 5,
 252                                         hltb_resp, &hltb_len,
 253                                         h->priv.iso14443b.fwt, 0);
 254         h->priv.iso14443b.state = ISO14443B_STATE_HLTB_SENT;
 255         if (ret < 0) {
 256                 DEBUGP("transceive problem\n");
 257                 return ret;
 258         }
 259
 260         if (hltb_len != 1 || hltb_resp[0] != 0x00) {
 261                 DEBUGP("bad HLTB response\n");
 262                 return -1;
 263         }
 264         h->priv.iso14443b.state = ISO14443B_STATE_HALTED;
 265
 266         return 0;
 267 }
 268
 269 static int
 270 iso14443b_anticol(struct rfid_layer2_handle *handle)
 271 {
 272         unsigned char afi = 0; /* FIXME */
 273         int ret;
 274         unsigned char buf[255];
 275         unsigned int buf_len = sizeof(buf);
 276
 277         ret = send_reqb(handle, afi, 0, 0);
 278         if (ret < 0)
 279                 return ret;
 280
 281         ret = transceive_attrib(handle, NULL, 0, buf, &buf_len);
 282         if (ret < 0)
 283                 return ret;
 284
 285         return 0;
 286 }
 287
 288 static struct rfid_layer2_handle *
 289 iso14443b_init(struct rfid_reader_handle *rh)
 290 {
 291         int ret;
 292         struct rfid_layer2_handle *h = malloc_layer2_handle(sizeof(*h));
 293         if (!h)
 294                 return NULL;
 295
 296         h->l2 = &rfid_layer2_iso14443b;
 297         h->rh = rh;
 298         h->priv.iso14443b.state = ISO14443B_STATE_NONE;
 299
 300         /* FIXME: if we want to support multiple PICC's, we need some
 301          * fancy allocation scheme for CID's */
 302         h->priv.iso14443b.cid = 0;
 303
 304         h->priv.iso14443b.fsd = iso14443_fsd_approx(rh->ah->mru);
 305         DEBUGP("fsd is %u\n", h->priv.iso14443b.fsd);
 306
 307         /* 14443-3 Section 7.1.6 */
 308         h->priv.iso14443b.tr0 = (256/ISO14443_FREQ_SUBCARRIER)*10e6;
 309         h->priv.iso14443b.tr1 = (200/ISO14443_FREQ_SUBCARRIER)*10e6;
 310
 311         ret = h->rh->reader->iso14443b.init(h->rh);
 312         if (ret < 0) {
 313                 DEBUGP("error during reader 14443b init\n");
 314                 free_layer2_handle(h);
 315                 return NULL;
 316         }
 317
 318         return h;
 319 }
 320
 321 static int
 322 iso14443b_fini(struct rfid_layer2_handle *handle)
 323 {
 324         free_layer2_handle(handle);
 325         return 0;
 326 }
 327
 328 static int
 329 iso14443b_transceive(struct rfid_layer2_handle *handle,
 330                      enum rfid_frametype frametype,
 331                      const unsigned char *tx_buf, unsigned int tx_len,
 332                      unsigned char *rx_buf, unsigned int *rx_len,
 333                      u_int64_t timeout, unsigned int flags)
 334 {
 335         DEBUGP("transcieving %u bytes, expecting max %u\n", tx_len, *rx_len);
 336         return handle->rh->reader->transceive(handle->rh, frametype,
 337                                               tx_buf, tx_len,
 338                                               rx_buf, rx_len, timeout, flags);
 339 }
 340
 341 static int
 342 iso14443b_getopt(struct rfid_layer2_handle *handle,
 343                  int optname, void *optval, unsigned int optlen)
 344 {
 345         unsigned int *opt_ui = optval;
 346
 347         switch (optname) {
 348         case RFID_OPT_14443B_CID:
 349                 *opt_ui = handle->priv.iso14443b.cid;
 350                 break;
 351         case RFID_OPT_14443B_FSC:
 352                 *opt_ui = handle->priv.iso14443b.fsc;
 353                 break;
 354         case RFID_OPT_14443B_FSD:
 355                 *opt_ui = handle->priv.iso14443b.fsd;
 356                 break;
 357         case RFID_OPT_14443B_FWT:
 358                 *opt_ui = handle->priv.iso14443b.fwt;
 359                 break;
 360         case RFID_OPT_14443B_TR0:
 361                 *opt_ui = handle->priv.iso14443b.tr0;
 362                 break;
 363         case RFID_OPT_14443B_TR1:
 364                 *opt_ui = handle->priv.iso14443b.tr1;
 365                 break;
 366         default:
 367                 return -EINVAL;
 368                 break;
 369         }
 370         return 0;
 371 }
 372
 373 static int
 374 iso14443b_setopt(struct rfid_layer2_handle *handle,
 375                  int optname, const void *optval, unsigned int optlen)
 376 {
 377         const unsigned int *opt_ui = optval;
 378
 379         switch (optname) {
 380         case RFID_OPT_14443B_CID:
 381                 handle->priv.iso14443b.cid = (*opt_ui & 0xf);
 382                 break;
 383         defaukt:
 384                 return -EINVAL;
 385                 break;
 386         }
 387         return 0;
 388 }
 389
 390
 391 const struct rfid_layer2 rfid_layer2_iso14443b = {
 392         .id     = RFID_LAYER2_ISO14443B,
 393         .name   = "ISO 14443-3 B",
 394         .fn     = {
 395                 .init           = &iso14443b_init,
 396                 .open           = &iso14443b_anticol,
 397                 .transceive     = &iso14443b_transceive,
 398                 .close          = &iso14443b_hltb,
 399                 .fini           = &iso14443b_fini,
 400                 .getopt         = &iso14443b_getopt,
 401                 .setopt         = &iso14443b_setopt,
 402         },
 403 };