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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, 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                 return -EINVAL;
 178
 179         /* initialize attrib frame */
 180         memset(&_attrib_buf, 0, sizeof(_attrib_buf));
 181         if (inf_len)
 182                 memcpy((unsigned char *)attrib+sizeof(*attrib), inf, inf_len);
 183
 184         attrib->one_d = 0x1d;
 185         memcpy(attrib->identifier, h->uid, 4);
 186
 187         /* FIXME: do we want to change TR0/TR1 from its default ? */
 188         /* FIXME: do we want to change SOF/EOF from its default ? */
 189
 190         ret = iso14443_fsd_to_fsdi(&fsdi, h->priv.iso14443b.fsd);
 191         if (ret < 0) {
 192                 DEBUGP("unable to map FSD(%u) to FSDI\n",
 193                         h->priv.iso14443b.fsd);
 194                 goto out_rx;
 195         }
 196         attrib->param2.fsdi = fsdi;
 197
 198         /* FIXME: spd_in / spd_out */
 199         if (h->priv.iso14443b.tcl_capable == 1)
 200                 attrib->param3.protocol_type = 0x1;
 201
 202         attrib->param4.cid = h->priv.iso14443b.cid & 0xf;
 203
 204         *rx_len = *rx_len + 1;
 205         ret = h->rh->reader->transceive(h->rh, RFID_14443B_FRAME_REGULAR,
 206                                         (unsigned char *) attrib,
 207                                         sizeof(*attrib)+inf_len,
 208                                         rx_buf, rx_len, h->priv.iso14443b.fwt,
 209                                         0);
 210         h->priv.iso14443b.state = ISO14443B_STATE_ATTRIB_SENT;
 211         if (ret < 0) {
 212                 DEBUGP("transceive problem\n");
 213                 goto out_rx;
 214         }
 215
 216         if ((rx_buf[0] & 0x0f) != h->priv.iso14443b.cid) {
 217                 DEBUGP("ATTRIB response with invalid CID %u (should be %u)\n",
 218                         rx_buf[0] & 0x0f, h->priv.iso14443b.cid);
 219                 ret = -1;
 220                 goto out_rx;
 221         }
 222
 223         h->priv.iso14443b.state = ISO14443B_STATE_SELECTED;
 224
 225         h->priv.iso14443b.mbl = mbli_to_mbl(h, (rx_data[0] & 0xf0) >> 4);
 226
 227         *rx_len = *rx_len - 1;
 228         memcpy(rx_data, rx_buf+1, *rx_len);
 229
 230 out_rx:
 231 out_attrib:
 232
 233         return ret;
 234 }
 235
 236 static int
 237 iso14443b_hltb(struct rfid_layer2_handle *h)
 238 {
 239         int ret;
 240         unsigned char hltb[5];
 241         unsigned char hltb_resp[1];
 242         unsigned int hltb_len = 1;
 243
 244         hltb[0] = 0x50;
 245         memcpy(hltb+1, h->uid, 4);
 246
 247         ret = h->rh->reader->transceive(h->rh, RFID_14443B_FRAME_REGULAR,
 248                                         hltb, 5,
 249                                         hltb_resp, &hltb_len,
 250                                         h->priv.iso14443b.fwt, 0);
 251         h->priv.iso14443b.state = ISO14443B_STATE_HLTB_SENT;
 252         if (ret < 0) {
 253                 DEBUGP("transceive problem\n");
 254                 return ret;
 255         }
 256
 257         if (hltb_len != 1 || hltb_resp[0] != 0x00) {
 258                 DEBUGP("bad HLTB response\n");
 259                 return -1;
 260         }
 261         h->priv.iso14443b.state = ISO14443B_STATE_HALTED;
 262
 263         return 0;
 264 }
 265
 266 static int
 267 iso14443b_anticol(struct rfid_layer2_handle *handle)
 268 {
 269         unsigned char afi = 0; /* FIXME */
 270         int ret;
 271         unsigned char buf[255];
 272         unsigned int buf_len = sizeof(buf);
 273
 274         ret = send_reqb(handle, afi, 0, 0);
 275         if (ret < 0)
 276                 return ret;
 277
 278         ret = transceive_attrib(handle, NULL, 0, buf, &buf_len);
 279         if (ret < 0)
 280                 return ret;
 281
 282         return 0;
 283 }
 284
 285 static struct rfid_layer2_handle *
 286 iso14443b_init(struct rfid_reader_handle *rh)
 287 {
 288         int ret;
 289         struct rfid_layer2_handle *h = malloc_layer2_handle(sizeof(*h));
 290         if (!h)
 291                 return NULL;
 292
 293         h->l2 = &rfid_layer2_iso14443b;
 294         h->rh = rh;
 295         h->priv.iso14443b.state = ISO14443B_STATE_NONE;
 296
 297         /* FIXME: if we want to support multiple PICC's, we need some
 298          * fancy allocation scheme for CID's */
 299         h->priv.iso14443b.cid = 0;
 300
 301         h->priv.iso14443b.fsd = iso14443_fsd_approx(rh->ah->mru);
 302         DEBUGP("fsd is %u\n", h->priv.iso14443b.fsd);
 303
 304         /* 14443-3 Section 7.1.6 */
 305         h->priv.iso14443b.tr0 = (256/ISO14443_FREQ_SUBCARRIER)*10e6;
 306         h->priv.iso14443b.tr1 = (200/ISO14443_FREQ_SUBCARRIER)*10e6;
 307
 308         ret = h->rh->reader->iso14443b.init(h->rh);
 309         if (ret < 0) {
 310                 DEBUGP("error during reader 14443b init\n");
 311                 free_layer2_handle(h);
 312                 return NULL;
 313         }
 314
 315         return h;
 316 }
 317
 318 static int
 319 iso14443b_fini(struct rfid_layer2_handle *handle)
 320 {
 321         free_layer2_handle(handle);
 322         return 0;
 323 }
 324
 325 static int
 326 iso14443b_transceive(struct rfid_layer2_handle *handle,
 327                      enum rfid_frametype frametype,
 328                      const unsigned char *tx_buf, unsigned int tx_len,
 329                      unsigned char *rx_buf, unsigned int *rx_len,
 330                      u_int64_t timeout, unsigned int flags)
 331 {
 332         DEBUGP("transcieving %u bytes, expecting max %u\n", tx_len, *rx_len);
 333         return handle->rh->reader->transceive(handle->rh, frametype,
 334                                               tx_buf, tx_len,
 335                                               rx_buf, rx_len, timeout, flags);
 336 }
 337
 338 static int
 339 iso14443b_getopt(struct rfid_layer2_handle *handle,
 340                  int optname, void *optval, unsigned int *optlen)
 341 {
 342         unsigned int *opt_ui = optval;
 343
 344         switch (optname) {
 345         case RFID_OPT_14443B_CID:
 346                 *opt_ui = handle->priv.iso14443b.cid;
 347                 break;
 348         case RFID_OPT_14443B_FSC:
 349                 *opt_ui = handle->priv.iso14443b.fsc;
 350                 break;
 351         case RFID_OPT_14443B_FSD:
 352                 *opt_ui = handle->priv.iso14443b.fsd;
 353                 break;
 354         case RFID_OPT_14443B_FWT:
 355                 *opt_ui = handle->priv.iso14443b.fwt;
 356                 break;
 357         case RFID_OPT_14443B_TR0:
 358                 *opt_ui = handle->priv.iso14443b.tr0;
 359                 break;
 360         case RFID_OPT_14443B_TR1:
 361                 *opt_ui = handle->priv.iso14443b.tr1;
 362                 break;
 363         default:
 364                 return -EINVAL;
 365                 break;
 366         }
 367         return 0;
 368 }
 369
 370 static int
 371 iso14443b_setopt(struct rfid_layer2_handle *handle,
 372                  int optname, const void *optval, unsigned int optlen)
 373 {
 374         const unsigned int *opt_ui = optval;
 375
 376         switch (optname) {
 377         case RFID_OPT_14443B_CID:
 378                 handle->priv.iso14443b.cid = (*opt_ui & 0xf);
 379                 break;
 380         defaukt:
 381                 return -EINVAL;
 382                 break;
 383         }
 384         return 0;
 385 }
 386
 387
 388 const struct rfid_layer2 rfid_layer2_iso14443b = {
 389         .id     = RFID_LAYER2_ISO14443B,
 390         .name   = "ISO 14443-3 B",
 391         .fn     = {
 392                 .init           = &iso14443b_init,
 393                 .open           = &iso14443b_anticol,
 394                 .transceive     = &iso14443b_transceive,
 395                 .close          = &iso14443b_hltb,
 396                 .fini           = &iso14443b_fini,
 397                 .getopt         = &iso14443b_getopt,
 398                 .setopt         = &iso14443b_setopt,
 399         },
 400 };