scd/iso7816.c

   1 /* iso7816.c - ISO 7816 commands
   2  * Copyright (C) 2003, 2004, 2008, 2009 Free Software Foundation, Inc.
   3  *
   4  * This file is part of GnuPG.
   5  *
   6  * GnuPG is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * GnuPG is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <config.h>
  21 #include <errno.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25
  26 #if defined(GNUPG_SCD_MAIN_HEADER)
  27 #include GNUPG_SCD_MAIN_HEADER
  28 #elif GNUPG_MAJOR_VERSION == 1
  29 /* This is used with GnuPG version < 1.9.  The code has been source
  30    copied from the current GnuPG >= 1.9  and is maintained over
  31    there. */
  32 #include "options.h"
  33 #include "errors.h"
  34 #include "memory.h"
  35 #include "util.h"
  36 #include "i18n.h"
  37 #else /* GNUPG_MAJOR_VERSION != 1 */
  38 #include "scdaemon.h"
  39 #endif /* GNUPG_MAJOR_VERSION != 1 */
  40
  41 #include "iso7816.h"
  42 #include "apdu.h"
  43
  44
  45 #define CMD_SELECT_FILE 0xA4
  46 #define CMD_VERIFY                ISO7816_VERIFY
  47 #define CMD_CHANGE_REFERENCE_DATA ISO7816_CHANGE_REFERENCE_DATA
  48 #define CMD_RESET_RETRY_COUNTER   ISO7816_RESET_RETRY_COUNTER
  49 #define CMD_GET_DATA    0xCA
  50 #define CMD_PUT_DATA    0xDA
  51 #define CMD_MSE         0x22
  52 #define CMD_PSO         0x2A
  53 #define CMD_INTERNAL_AUTHENTICATE 0x88
  54 #define CMD_GENERATE_KEYPAIR      0x47
  55 #define CMD_GET_CHALLENGE         0x84
  56 #define CMD_READ_BINARY 0xB0
  57 #define CMD_READ_RECORD 0xB2
  58
  59 static gpg_error_t
  60 map_sw (int sw)
  61 {
  62   gpg_err_code_t ec;
  63
  64   switch (sw)
  65     {
  66     case SW_EEPROM_FAILURE: ec = GPG_ERR_HARDWARE; break;
  67     case SW_TERM_STATE:     ec = GPG_ERR_CARD; break;
  68     case SW_WRONG_LENGTH:   ec = GPG_ERR_INV_VALUE; break;
  69     case SW_SM_NOT_SUP:     ec = GPG_ERR_NOT_SUPPORTED; break;
  70     case SW_CC_NOT_SUP:     ec = GPG_ERR_NOT_SUPPORTED; break;
  71     case SW_CHV_WRONG:      ec = GPG_ERR_BAD_PIN; break;
  72     case SW_CHV_BLOCKED:    ec = GPG_ERR_PIN_BLOCKED; break;
  73     case SW_USE_CONDITIONS: ec = GPG_ERR_USE_CONDITIONS; break;
  74     case SW_NOT_SUPPORTED:  ec = GPG_ERR_NOT_SUPPORTED; break;
  75     case SW_BAD_PARAMETER:  ec = GPG_ERR_INV_VALUE; break;
  76     case SW_FILE_NOT_FOUND: ec = GPG_ERR_ENOENT; break;
  77     case SW_RECORD_NOT_FOUND:ec= GPG_ERR_NOT_FOUND; break;
  78     case SW_REF_NOT_FOUND:  ec = GPG_ERR_NO_OBJ; break;
  79     case SW_BAD_P0_P1:      ec = GPG_ERR_INV_VALUE; break;
  80     case SW_EXACT_LENGTH:   ec = GPG_ERR_INV_VALUE; break;
  81     case SW_INS_NOT_SUP:    ec = GPG_ERR_CARD; break;
  82     case SW_CLA_NOT_SUP:    ec = GPG_ERR_CARD; break;
  83     case SW_SUCCESS:        ec = 0; break;
  84
  85     case SW_HOST_OUT_OF_CORE: ec = GPG_ERR_ENOMEM; break;
  86     case SW_HOST_INV_VALUE:   ec = GPG_ERR_INV_VALUE; break;
  87     case SW_HOST_INCOMPLETE_CARD_RESPONSE: ec = GPG_ERR_CARD; break;
  88     case SW_HOST_NOT_SUPPORTED: ec = GPG_ERR_NOT_SUPPORTED; break;
  89     case SW_HOST_LOCKING_FAILED: ec = GPG_ERR_BUG; break;
  90     case SW_HOST_BUSY:           ec = GPG_ERR_EBUSY; break;
  91     case SW_HOST_NO_CARD:        ec = GPG_ERR_CARD_NOT_PRESENT; break;
  92     case SW_HOST_CARD_INACTIVE:  ec = GPG_ERR_CARD_RESET; break;
  93     case SW_HOST_CARD_IO_ERROR:  ec = GPG_ERR_EIO; break;
  94     case SW_HOST_GENERAL_ERROR:  ec = GPG_ERR_GENERAL; break;
  95     case SW_HOST_NO_READER:      ec = GPG_ERR_ENODEV; break;
  96     case SW_HOST_ABORTED:        ec = GPG_ERR_CANCELED; break;
  97     case SW_HOST_NO_KEYPAD:      ec = GPG_ERR_NOT_SUPPORTED; break;
  98
  99     default:
 100       if ((sw & 0x010000))
 101         ec = GPG_ERR_GENERAL; /* Should not happen. */
 102       else if ((sw & 0xff00) == SW_MORE_DATA)
 103         ec = 0; /* This should actually never been seen here. */
 104       else
 105         ec = GPG_ERR_CARD;
 106     }
 107   return gpg_error (ec);
 108 }
 109
 110 /* Map a status word from the APDU layer to a gpg-error code.  */
 111 gpg_error_t
 112 iso7816_map_sw (int sw)
 113 {
 114   /* All APDU functions should return 0x9000 on success but for
 115      historical reasons of the implementation some return 0 to
 116      indicate success.  We allow for that here. */
 117   return sw? map_sw (sw) : 0;
 118 }
 119
 120
 121 /* This function is specialized version of the SELECT FILE command.
 122    SLOT is the card and reader as created for example by
 123    apdu_open_reader (), AID is a buffer of size AIDLEN holding the
 124    requested application ID.  The function can't be used to enumerate
 125    AIDs and won't return the AID on success.  The return value is 0
 126    for okay or a GPG error code.  Note that ISO error codes are
 127    internally mapped.  Bit 0 of FLAGS should be set if the card does
 128    not understand P2=0xC0. */
 129 gpg_error_t
 130 iso7816_select_application (int slot, const char *aid, size_t aidlen,
 131                             unsigned int flags)
 132 {
 133   int sw;
 134   sw = apdu_send_simple (slot, 0, 0x00, CMD_SELECT_FILE, 4,
 135                          (flags&1)? 0 :0x0c, aidlen, aid);
 136   return map_sw (sw);
 137 }
 138
 139
 140 gpg_error_t
 141 iso7816_select_file (int slot, int tag, int is_dir,
 142                      unsigned char **result, size_t *resultlen)
 143 {
 144   int sw, p0, p1;
 145   unsigned char tagbuf[2];
 146
 147   tagbuf[0] = (tag >> 8) & 0xff;
 148   tagbuf[1] = tag & 0xff;
 149
 150   if (result || resultlen)
 151     {
 152       *result = NULL;
 153       *resultlen = 0;
 154       return gpg_error (GPG_ERR_NOT_IMPLEMENTED);
 155     }
 156   else
 157     {
 158       p0 = (tag == 0x3F00)? 0: is_dir? 1:2;
 159       p1 = 0x0c; /* No FC return. */
 160       sw = apdu_send_simple (slot, 0, 0x00, CMD_SELECT_FILE,
 161                              p0, p1, 2, (char*)tagbuf );
 162       return map_sw (sw);
 163     }
 164
 165   return 0;
 166 }
 167
 168
 169 /* Do a select file command with a direct path. */
 170 gpg_error_t
 171 iso7816_select_path (int slot, const unsigned short *path, size_t pathlen,
 172                      unsigned char **result, size_t *resultlen)
 173 {
 174   int sw, p0, p1;
 175   unsigned char buffer[100];
 176   int buflen;
 177
 178   if (result || resultlen)
 179     {
 180       *result = NULL;
 181       *resultlen = 0;
 182       return gpg_error (GPG_ERR_NOT_IMPLEMENTED);
 183     }
 184
 185   if (pathlen/2 >= sizeof buffer)
 186     return gpg_error (GPG_ERR_TOO_LARGE);
 187
 188   for (buflen = 0; pathlen; pathlen--, path++)
 189     {
 190       buffer[buflen++] = (*path >> 8);
 191       buffer[buflen++] = *path;
 192     }
 193
 194   p0 = 0x08;
 195   p1 = 0x0c; /* No FC return. */
 196   sw = apdu_send_simple (slot, 0, 0x00, CMD_SELECT_FILE,
 197                          p0, p1, buflen, (char*)buffer );
 198   return map_sw (sw);
 199 }
 200
 201
 202 /* This is a private command currently only working for TCOS cards. */
 203 gpg_error_t
 204 iso7816_list_directory (int slot, int list_dirs,
 205                         unsigned char **result, size_t *resultlen)
 206 {
 207   int sw;
 208
 209   if (!result || !resultlen)
 210     return gpg_error (GPG_ERR_INV_VALUE);
 211   *result = NULL;
 212   *resultlen = 0;
 213
 214   sw = apdu_send (slot, 0, 0x80, 0xAA, list_dirs? 1:2, 0, -1, NULL,
 215                   result, resultlen);
 216   if (sw != SW_SUCCESS)
 217     {
 218       /* Make sure that pending buffers are released. */
 219       xfree (*result);
 220       *result = NULL;
 221       *resultlen = 0;
 222     }
 223   return map_sw (sw);
 224 }
 225
 226
 227 /* This funcion sends an already formatted APDU to the card.  With
 228    HANDLE_MORE set to true a MORE DATA status will be handled
 229    internally.  The return value is a gpg error code (i.e. a mapped
 230    status word).  This is basically the same as apdu_send_direct but
 231    it maps the status word and does not return it in the result
 232    buffer.  */
 233 gpg_error_t
 234 iso7816_apdu_direct (int slot, const void *apdudata, size_t apdudatalen,
 235                      int handle_more,
 236                      unsigned char **result, size_t *resultlen)
 237 {
 238   int sw;
 239
 240   if (!result || !resultlen)
 241     return gpg_error (GPG_ERR_INV_VALUE);
 242   *result = NULL;
 243   *resultlen = 0;
 244
 245   sw = apdu_send_direct (slot, 0, apdudata, apdudatalen, handle_more,
 246                          result, resultlen);
 247   if (!sw)
 248     {
 249       if (*resultlen < 2)
 250         sw = SW_HOST_GENERAL_ERROR;
 251       else
 252         {
 253           sw = ((*result)[*resultlen-2] << 8) | (*result)[*resultlen-1];
 254           (*resultlen)--;
 255           (*resultlen)--;
 256         }
 257     }
 258   if (sw != SW_SUCCESS)
 259     {
 260       /* Make sure that pending buffers are released. */
 261       xfree (*result);
 262       *result = NULL;
 263       *resultlen = 0;
 264     }
 265   return map_sw (sw);
 266 }
 267
 268
 269 /* Check whether the reader supports the ISO command code COMMAND on
 270    the keypad.  Returns 0 on success.  */
 271 gpg_error_t
 272 iso7816_check_keypad (int slot, int command, iso7816_pininfo_t *pininfo)
 273 {
 274   int sw;
 275
 276   sw = apdu_check_keypad (slot, command,
 277                           pininfo->mode, pininfo->minlen, pininfo->maxlen,
 278                           pininfo->padlen);
 279   return iso7816_map_sw (sw);
 280 }
 281
 282
 283 /* Perform a VERIFY command on SLOT using the card holder verification
 284    vector CHVNO with a CHV of lenght CHVLEN.  With PININFO non-NULL
 285    the keypad of the reader will be used.  Returns 0 on success. */
 286 gpg_error_t
 287 iso7816_verify_kp (int slot, int chvno, const char *chv, size_t chvlen,
 288                    iso7816_pininfo_t *pininfo)
 289 {
 290   int sw;
 291
 292   if (pininfo && pininfo->mode)
 293     sw = apdu_send_simple_kp (slot, 0x00, CMD_VERIFY, 0, chvno, chvlen, chv,
 294                               pininfo->mode,
 295                               pininfo->minlen,
 296                               pininfo->maxlen,
 297                               pininfo->padlen);
 298   else
 299     sw = apdu_send_simple (slot, 0, 0x00, CMD_VERIFY, 0, chvno, chvlen, chv);
 300   return map_sw (sw);
 301 }
 302
 303 /* Perform a VERIFY command on SLOT using the card holder verification
 304    vector CHVNO with a CHV of lenght CHVLEN.  Returns 0 on success. */
 305 gpg_error_t
 306 iso7816_verify (int slot, int chvno, const char *chv, size_t chvlen)
 307 {
 308   return iso7816_verify_kp (slot, chvno, chv, chvlen, NULL);
 309 }
 310
 311 /* Perform a CHANGE_REFERENCE_DATA command on SLOT for the card holder
 312    verification vector CHVNO.  If the OLDCHV is NULL (and OLDCHVLEN
 313    0), a "change reference data" is done, otherwise an "exchange
 314    reference data".  The new reference data is expected in NEWCHV of
 315    length NEWCHVLEN.  With PININFO non-NULL the keypad of the reader
 316    will be used.  */
 317 gpg_error_t
 318 iso7816_change_reference_data_kp (int slot, int chvno,
 319                                   const char *oldchv, size_t oldchvlen,
 320                                   const char *newchv, size_t newchvlen,
 321                                   iso7816_pininfo_t *pininfo)
 322 {
 323   int sw;
 324   char *buf;
 325
 326   if ((!oldchv && oldchvlen)
 327       || (oldchv && !oldchvlen)
 328       || !newchv || !newchvlen )
 329     return gpg_error (GPG_ERR_INV_VALUE);
 330
 331   buf = xtrymalloc (oldchvlen + newchvlen);
 332   if (!buf)
 333     return gpg_error (gpg_err_code_from_errno (errno));
 334   if (oldchvlen)
 335     memcpy (buf, oldchv, oldchvlen);
 336   memcpy (buf+oldchvlen, newchv, newchvlen);
 337
 338   if (pininfo && pininfo->mode)
 339     sw = apdu_send_simple_kp (slot, 0x00, CMD_CHANGE_REFERENCE_DATA,
 340                            oldchvlen? 0 : 1, chvno, oldchvlen+newchvlen, buf,
 341                            pininfo->mode,
 342                            pininfo->minlen,
 343                            pininfo->maxlen,
 344                            pininfo->padlen);
 345   else
 346     sw = apdu_send_simple (slot, 0, 0x00, CMD_CHANGE_REFERENCE_DATA,
 347                            oldchvlen? 0 : 1, chvno, oldchvlen+newchvlen, buf);
 348   xfree (buf);
 349   return map_sw (sw);
 350
 351 }
 352
 353 /* Perform a CHANGE_REFERENCE_DATA command on SLOT for the card holder
 354    verification vector CHVNO.  If the OLDCHV is NULL (and OLDCHVLEN
 355    0), a "change reference data" is done, otherwise an "exchange
 356    reference data".  The new reference data is expected in NEWCHV of
 357    length NEWCHVLEN.  */
 358 gpg_error_t
 359 iso7816_change_reference_data (int slot, int chvno,
 360                                const char *oldchv, size_t oldchvlen,
 361                                const char *newchv, size_t newchvlen)
 362 {
 363   return iso7816_change_reference_data_kp (slot, chvno, oldchv, oldchvlen,
 364                                            newchv, newchvlen, NULL);
 365 }
 366
 367
 368 gpg_error_t
 369 iso7816_reset_retry_counter_kp (int slot, int chvno,
 370                                 const char *newchv, size_t newchvlen,
 371                                 iso7816_pininfo_t *pininfo)
 372 {
 373   int sw;
 374
 375   if (!newchv || !newchvlen )
 376     return gpg_error (GPG_ERR_INV_VALUE);
 377
 378   /* FIXME:  The keypad mode has not yet been tested.  */
 379   if (pininfo && pininfo->mode)
 380     sw = apdu_send_simple_kp (slot, 0x00, CMD_RESET_RETRY_COUNTER,
 381                            2, chvno, newchvlen, newchv,
 382                            pininfo->mode,
 383                            pininfo->minlen,
 384                            pininfo->maxlen,
 385                            pininfo->padlen);
 386   else
 387     sw = apdu_send_simple (slot, 0, 0x00, CMD_RESET_RETRY_COUNTER,
 388                            2, chvno, newchvlen, newchv);
 389   return map_sw (sw);
 390 }
 391
 392
 393 gpg_error_t
 394 iso7816_reset_retry_counter_with_rc (int slot, int chvno,
 395                                      const char *data, size_t datalen)
 396 {
 397   int sw;
 398
 399   if (!data || !datalen )
 400     return gpg_error (GPG_ERR_INV_VALUE);
 401
 402   sw = apdu_send_simple (slot, 0, 0x00, CMD_RESET_RETRY_COUNTER,
 403                          0, chvno, datalen, data);
 404   return map_sw (sw);
 405 }
 406
 407
 408 gpg_error_t
 409 iso7816_reset_retry_counter (int slot, int chvno,
 410                              const char *newchv, size_t newchvlen)
 411 {
 412   return iso7816_reset_retry_counter_kp (slot, chvno, newchv, newchvlen, NULL);
 413 }
 414
 415
 416
 417 /* Perform a GET DATA command requesting TAG and storing the result in
 418    a newly allocated buffer at the address passed by RESULT.  Return
 419    the length of this data at the address of RESULTLEN. */
 420 gpg_error_t
 421 iso7816_get_data (int slot, int extended_mode, int tag,
 422                   unsigned char **result, size_t *resultlen)
 423 {
 424   int sw;
 425   int le;
 426
 427   if (!result || !resultlen)
 428     return gpg_error (GPG_ERR_INV_VALUE);
 429   *result = NULL;
 430   *resultlen = 0;
 431
 432   if (extended_mode > 0 && extended_mode < 256)
 433     le = 65534; /* Not 65535 in case it is used as some special flag.  */
 434   else if (extended_mode > 0)
 435     le = extended_mode;
 436   else
 437     le = 256;
 438
 439   sw = apdu_send_le (slot, extended_mode, 0x00, CMD_GET_DATA,
 440                      ((tag >> 8) & 0xff), (tag & 0xff), -1, NULL, le,
 441                      result, resultlen);
 442   if (sw != SW_SUCCESS)
 443     {
 444       /* Make sure that pending buffers are released. */
 445       xfree (*result);
 446       *result = NULL;
 447       *resultlen = 0;
 448       return map_sw (sw);
 449     }
 450
 451   return 0;
 452 }
 453
 454
 455 /* Perform a PUT DATA command on card in SLOT.  Write DATA of length
 456    DATALEN to TAG.  EXTENDED_MODE controls whether extended length
 457    headers or command chaining is used instead of single length
 458    bytes. */
 459 gpg_error_t
 460 iso7816_put_data (int slot, int extended_mode, int tag,
 461                   const void *data, size_t datalen)
 462 {
 463   int sw;
 464
 465   sw = apdu_send_simple (slot, extended_mode, 0x00, CMD_PUT_DATA,
 466                          ((tag >> 8) & 0xff), (tag & 0xff),
 467                          datalen, (const char*)data);
 468   return map_sw (sw);
 469 }
 470
 471 /* Same as iso7816_put_data but uses an odd instruction byte.  */
 472 gpg_error_t
 473 iso7816_put_data_odd (int slot, int extended_mode, int tag,
 474                       const void *data, size_t datalen)
 475 {
 476   int sw;
 477
 478   sw = apdu_send_simple (slot, extended_mode, 0x00, CMD_PUT_DATA+1,
 479                          ((tag >> 8) & 0xff), (tag & 0xff),
 480                          datalen, (const char*)data);
 481   return map_sw (sw);
 482 }
 483
 484 /* Manage Security Environment.  This is a weird operation and there
 485    is no easy abstraction for it.  Furthermore, some card seem to have
 486    a different interpreation of 7816-8 and thus we resort to let the
 487    caller decide what to do. */
 488 gpg_error_t
 489 iso7816_manage_security_env (int slot, int p1, int p2,
 490                              const unsigned char *data, size_t datalen)
 491 {
 492   int sw;
 493
 494   if (p1 < 0 || p1 > 255 || p2 < 0 || p2 > 255 )
 495     return gpg_error (GPG_ERR_INV_VALUE);
 496
 497   sw = apdu_send_simple (slot, 0, 0x00, CMD_MSE, p1, p2,
 498                          data? datalen : -1, (const char*)data);
 499   return map_sw (sw);
 500 }
 501
 502
 503 /* Perform the security operation COMPUTE DIGITAL SIGANTURE.  On
 504    success 0 is returned and the data is availavle in a newly
 505    allocated buffer stored at RESULT with its length stored at
 506    RESULTLEN.  For LE see do_generate_keypair. */
 507 gpg_error_t
 508 iso7816_compute_ds (int slot, int extended_mode,
 509                     const unsigned char *data, size_t datalen, int le,
 510                     unsigned char **result, size_t *resultlen)
 511 {
 512   int sw;
 513
 514   if (!data || !datalen || !result || !resultlen)
 515     return gpg_error (GPG_ERR_INV_VALUE);
 516   *result = NULL;
 517   *resultlen = 0;
 518
 519   if (!extended_mode)
 520     le = 256;  /* Ignore provided Le and use what apdu_send uses. */
 521   else if (le >= 0 && le < 256)
 522     le = 256;
 523
 524   sw = apdu_send_le (slot, extended_mode,
 525                      0x00, CMD_PSO, 0x9E, 0x9A,
 526                      datalen, (const char*)data,
 527                      le,
 528                      result, resultlen);
 529   if (sw != SW_SUCCESS)
 530     {
 531       /* Make sure that pending buffers are released. */
 532       xfree (*result);
 533       *result = NULL;
 534       *resultlen = 0;
 535       return map_sw (sw);
 536     }
 537
 538   return 0;
 539 }
 540
 541
 542 /* Perform the security operation DECIPHER.  PADIND is the padding
 543    indicator to be used.  It should be 0 if no padding is required, a
 544    value of -1 suppresses the padding byte.  On success 0 is returned
 545    and the plaintext is available in a newly allocated buffer stored
 546    at RESULT with its length stored at RESULTLEN.  For LE see
 547    do_generate_keypair. */
 548 gpg_error_t
 549 iso7816_decipher (int slot, int extended_mode,
 550                   const unsigned char *data, size_t datalen, int le,
 551                   int padind, unsigned char **result, size_t *resultlen)
 552 {
 553   int sw;
 554   unsigned char *buf;
 555
 556   if (!data || !datalen || !result || !resultlen)
 557     return gpg_error (GPG_ERR_INV_VALUE);
 558   *result = NULL;
 559   *resultlen = 0;
 560
 561   if (!extended_mode)
 562     le = 256;  /* Ignore provided Le and use what apdu_send uses. */
 563   else if (le >= 0 && le < 256)
 564     le = 256;
 565
 566   if (padind >= 0)
 567     {
 568       /* We need to prepend the padding indicator. */
 569       buf = xtrymalloc (datalen + 1);
 570       if (!buf)
 571         return gpg_error (gpg_err_code_from_errno (errno));
 572
 573       *buf = padind; /* Padding indicator. */
 574       memcpy (buf+1, data, datalen);
 575       sw = apdu_send_le (slot, extended_mode,
 576                          0x00, CMD_PSO, 0x80, 0x86,
 577                          datalen+1, (char*)buf, le,
 578                          result, resultlen);
 579       xfree (buf);
 580     }
 581   else
 582     {
 583       sw = apdu_send_le (slot, extended_mode,
 584                          0x00, CMD_PSO, 0x80, 0x86,
 585                          datalen, (const char *)data, le,
 586                          result, resultlen);
 587     }
 588   if (sw != SW_SUCCESS)
 589     {
 590       /* Make sure that pending buffers are released. */
 591       xfree (*result);
 592       *result = NULL;
 593       *resultlen = 0;
 594       return map_sw (sw);
 595     }
 596
 597   return 0;
 598 }
 599
 600
 601 /*  For LE see do_generate_keypair.  */
 602 gpg_error_t
 603 iso7816_internal_authenticate (int slot, int extended_mode,
 604                                const unsigned char *data, size_t datalen,
 605                                int le,
 606                                unsigned char **result, size_t *resultlen)
 607 {
 608   int sw;
 609
 610   if (!data || !datalen || !result || !resultlen)
 611     return gpg_error (GPG_ERR_INV_VALUE);
 612   *result = NULL;
 613   *resultlen = 0;
 614
 615   if (!extended_mode)
 616     le = 256;  /* Ignore provided Le and use what apdu_send uses. */
 617   else if (le >= 0 && le < 256)
 618     le = 256;
 619
 620   sw = apdu_send_le (slot, extended_mode,
 621                      0x00, CMD_INTERNAL_AUTHENTICATE, 0, 0,
 622                      datalen, (const char*)data,
 623                      le,
 624                      result, resultlen);
 625   if (sw != SW_SUCCESS)
 626     {
 627       /* Make sure that pending buffers are released. */
 628       xfree (*result);
 629       *result = NULL;
 630       *resultlen = 0;
 631       return map_sw (sw);
 632     }
 633
 634   return 0;
 635 }
 636
 637
 638 /* LE is the expected return length.  This is usually 0 except if
 639    extended length mode is used and more than 256 byte will be
 640    returned.  In that case a value of -1 uses a large default
 641    (e.g. 4096 bytes), a value larger 256 used that value.  */
 642 static gpg_error_t
 643 do_generate_keypair (int slot, int extended_mode, int readonly,
 644                      const unsigned char *data, size_t datalen,
 645                      int le,
 646                      unsigned char **result, size_t *resultlen)
 647 {
 648   int sw;
 649
 650   if (!data || !datalen || !result || !resultlen)
 651     return gpg_error (GPG_ERR_INV_VALUE);
 652   *result = NULL;
 653   *resultlen = 0;
 654
 655   sw = apdu_send_le (slot, extended_mode,
 656                      0x00, CMD_GENERATE_KEYPAIR, readonly? 0x81:0x80, 0,
 657                      datalen, (const char*)data,
 658                      le >= 0 && le < 256? 256:le,
 659                      result, resultlen);
 660   if (sw != SW_SUCCESS)
 661     {
 662       /* Make sure that pending buffers are released. */
 663       xfree (*result);
 664       *result = NULL;
 665       *resultlen = 0;
 666       return map_sw (sw);
 667     }
 668
 669   return 0;
 670 }
 671
 672
 673 gpg_error_t
 674 iso7816_generate_keypair (int slot, int extended_mode,
 675                           const unsigned char *data, size_t datalen,
 676                           int le,
 677                           unsigned char **result, size_t *resultlen)
 678 {
 679   return do_generate_keypair (slot, extended_mode, 0,
 680                               data, datalen, le, result, resultlen);
 681 }
 682
 683
 684 gpg_error_t
 685 iso7816_read_public_key (int slot, int extended_mode,
 686                          const unsigned char *data, size_t datalen,
 687                          int le,
 688                          unsigned char **result, size_t *resultlen)
 689 {
 690   return do_generate_keypair (slot, extended_mode, 1,
 691                               data, datalen, le, result, resultlen);
 692 }
 693
 694
 695
 696 gpg_error_t
 697 iso7816_get_challenge (int slot, int length, unsigned char *buffer)
 698 {
 699   int sw;
 700   unsigned char *result;
 701   size_t resultlen, n;
 702
 703   if (!buffer || length < 1)
 704     return gpg_error (GPG_ERR_INV_VALUE);
 705
 706   do
 707     {
 708       result = NULL;
 709       n = length > 254? 254 : length;
 710       sw = apdu_send_le (slot, 0,
 711                          0x00, CMD_GET_CHALLENGE, 0, 0, -1, NULL, n,
 712                          &result, &resultlen);
 713       if (sw != SW_SUCCESS)
 714         {
 715           /* Make sure that pending buffers are released. */
 716           xfree (result);
 717           return map_sw (sw);
 718         }
 719       if (resultlen > n)
 720         resultlen = n;
 721       memcpy (buffer, result, resultlen);
 722       buffer += resultlen;
 723       length -= resultlen;
 724       xfree (result);
 725     }
 726   while (length > 0);
 727
 728   return 0;
 729 }
 730
 731 /* Perform a READ BINARY command requesting a maximum of NMAX bytes
 732    from OFFSET.  With NMAX = 0 the entire file is read. The result is
 733    stored in a newly allocated buffer at the address passed by RESULT.
 734    Returns the length of this data at the address of RESULTLEN. */
 735 gpg_error_t
 736 iso7816_read_binary (int slot, size_t offset, size_t nmax,
 737                      unsigned char **result, size_t *resultlen)
 738 {
 739   int sw;
 740   unsigned char *buffer;
 741   size_t bufferlen;
 742   int read_all = !nmax;
 743   size_t n;
 744
 745   if (!result || !resultlen)
 746     return gpg_error (GPG_ERR_INV_VALUE);
 747   *result = NULL;
 748   *resultlen = 0;
 749
 750   /* We can only encode 15 bits in p0,p1 to indicate an offset. Thus
 751      we check for this limit. */
 752   if (offset > 32767)
 753     return gpg_error (GPG_ERR_INV_VALUE);
 754
 755   do
 756     {
 757       buffer = NULL;
 758       bufferlen = 0;
 759       n = read_all? 0 : nmax;
 760       sw = apdu_send_le (slot, 0, 0x00, CMD_READ_BINARY,
 761                          ((offset>>8) & 0xff), (offset & 0xff) , -1, NULL,
 762                          n, &buffer, &bufferlen);
 763       if ( SW_EXACT_LENGTH_P(sw) )
 764         {
 765           n = (sw & 0x00ff);
 766           sw = apdu_send_le (slot, 0, 0x00, CMD_READ_BINARY,
 767                              ((offset>>8) & 0xff), (offset & 0xff) , -1, NULL,
 768                              n, &buffer, &bufferlen);
 769         }
 770
 771       if (*result && sw == SW_BAD_P0_P1)
 772         {
 773           /* Bad Parameter means that the offset is outside of the
 774              EF. When reading all data we take this as an indication
 775              for EOF.  */
 776           break;
 777         }
 778
 779       if (sw != SW_SUCCESS && sw != SW_EOF_REACHED)
 780         {
 781           /* Make sure that pending buffers are released. */
 782           xfree (buffer);
 783           xfree (*result);
 784           *result = NULL;
 785           *resultlen = 0;
 786           return map_sw (sw);
 787         }
 788       if (*result) /* Need to extend the buffer. */
 789         {
 790           unsigned char *p = xtryrealloc (*result, *resultlen + bufferlen);
 791           if (!p)
 792             {
 793               gpg_error_t err = gpg_error_from_syserror ();
 794               xfree (buffer);
 795               xfree (*result);
 796               *result = NULL;
 797               *resultlen = 0;
 798               return err;
 799             }
 800           *result = p;
 801           memcpy (*result + *resultlen, buffer, bufferlen);
 802           *resultlen += bufferlen;
 803           xfree (buffer);
 804           buffer = NULL;
 805         }
 806       else /* Transfer the buffer into our result. */
 807         {
 808           *result = buffer;
 809           *resultlen = bufferlen;
 810         }
 811       offset += bufferlen;
 812       if (offset > 32767)
 813         break; /* We simply truncate the result for too large
 814                   files. */
 815       if (nmax > bufferlen)
 816         nmax -= bufferlen;
 817       else
 818         nmax = 0;
 819     }
 820   while ((read_all && sw != SW_EOF_REACHED) || (!read_all && nmax));
 821
 822   return 0;
 823 }
 824
 825 /* Perform a READ RECORD command. RECNO gives the record number to
 826    read with 0 indicating the current record.  RECCOUNT must be 1 (not
 827    all cards support reading of more than one record).  SHORT_EF
 828    should be 0 to read the current EF or contain a short EF. The
 829    result is stored in a newly allocated buffer at the address passed
 830    by RESULT.  Returns the length of this data at the address of
 831    RESULTLEN. */
 832 gpg_error_t
 833 iso7816_read_record (int slot, int recno, int reccount, int short_ef,
 834                      unsigned char **result, size_t *resultlen)
 835 {
 836   int sw;
 837   unsigned char *buffer;
 838   size_t bufferlen;
 839
 840   if (!result || !resultlen)
 841     return gpg_error (GPG_ERR_INV_VALUE);
 842   *result = NULL;
 843   *resultlen = 0;
 844
 845   /* We can only encode 15 bits in p0,p1 to indicate an offset. Thus
 846      we check for this limit. */
 847   if (recno < 0 || recno > 255 || reccount != 1
 848       || short_ef < 0 || short_ef > 254 )
 849     return gpg_error (GPG_ERR_INV_VALUE);
 850
 851   buffer = NULL;
 852   bufferlen = 0;
 853   sw = apdu_send_le (slot, 0, 0x00, CMD_READ_RECORD,
 854                      recno,
 855                      short_ef? short_ef : 0x04,
 856                      -1, NULL,
 857                      0, &buffer, &bufferlen);
 858
 859   if (sw != SW_SUCCESS && sw != SW_EOF_REACHED)
 860     {
 861       /* Make sure that pending buffers are released. */
 862       xfree (buffer);
 863       xfree (*result);
 864       *result = NULL;
 865       *resultlen = 0;
 866       return map_sw (sw);
 867     }
 868   *result = buffer;
 869   *resultlen = bufferlen;
 870
 871   return 0;
 872 }
 873