sm/call-agent.c

   1 /* call-agent.c - Divert GPGSM operations to the agent
   2  * Copyright (C) 2001, 2002, 2003, 2005, 2007,
   3  *               2008, 2009 Free Software Foundation, Inc.
   4  *
   5  * This file is part of GnuPG.
   6  *
   7  * GnuPG is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 3 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * GnuPG 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, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include <config.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <errno.h>
  26 #include <unistd.h>
  27 #include <time.h>
  28 #include <assert.h>
  29 #ifdef HAVE_LOCALE_H
  30 #include <locale.h>
  31 #endif
  32
  33 #include "gpgsm.h"
  34 #include <gcrypt.h>
  35 #include <assuan.h>
  36 #include "i18n.h"
  37 #include "asshelp.h"
  38 #include "keydb.h" /* fixme: Move this to import.c */
  39 #include "membuf.h"
  40
  41
  42 static assuan_context_t agent_ctx = NULL;
  43
  44
  45 struct cipher_parm_s
  46 {
  47   ctrl_t ctrl;
  48   assuan_context_t ctx;
  49   const unsigned char *ciphertext;
  50   size_t ciphertextlen;
  51 };
  52
  53 struct genkey_parm_s
  54 {
  55   ctrl_t ctrl;
  56   assuan_context_t ctx;
  57   const unsigned char *sexp;
  58   size_t sexplen;
  59 };
  60
  61 struct learn_parm_s
  62 {
  63   int error;
  64   ctrl_t ctrl;
  65   assuan_context_t ctx;
  66   membuf_t *data;
  67 };
  68
  69
  70 \f
  71 /* Try to connect to the agent via socket or fork it off and work by
  72    pipes.  Handle the server's initial greeting */
  73 static int
  74 start_agent (ctrl_t ctrl)
  75 {
  76   int rc;
  77
  78   if (agent_ctx)
  79     rc = 0;      /* fixme: We need a context for each thread or
  80                     serialize the access to the agent (which is
  81                     suitable given that the agent is not MT. */
  82   else
  83     {
  84       rc = start_new_gpg_agent (&agent_ctx,
  85                                 GPG_ERR_SOURCE_DEFAULT,
  86                                 opt.homedir,
  87                                 opt.agent_program,
  88                                 opt.display, opt.ttyname, opt.ttytype,
  89                                 opt.lc_ctype, opt.lc_messages,
  90                                 opt.xauthority, opt.pinentry_user_data,
  91                                 opt.verbose, DBG_ASSUAN,
  92                                 gpgsm_status2, ctrl);
  93
  94       if (!rc)
  95         {
  96           /* Tell the agent that we support Pinentry notifications.  No
  97              error checking so that it will work also with older
  98              agents.  */
  99           assuan_transact (agent_ctx, "OPTION allow-pinentry-notify",
 100                            NULL, NULL, NULL, NULL, NULL, NULL);
 101         }
 102     }
 103
 104   if (!ctrl->agent_seen)
 105     {
 106       ctrl->agent_seen = 1;
 107       audit_log_ok (ctrl->audit, AUDIT_AGENT_READY, rc);
 108     }
 109
 110   return rc;
 111 }
 112
 113
 114
 115 static int
 116 membuf_data_cb (void *opaque, const void *buffer, size_t length)
 117 {
 118   membuf_t *data = opaque;
 119
 120   if (buffer)
 121     put_membuf (data, buffer, length);
 122   return 0;
 123 }
 124
 125
 126 /* This is the default inquiry callback.  It mainly handles the
 127    Pinentry notifications.  */
 128 static int
 129 default_inq_cb (void *opaque, const char *line)
 130 {
 131   gpg_error_t err;
 132   ctrl_t ctrl = opaque;
 133
 134   if (!strncmp (line, "PINENTRY_LAUNCHED", 17) && (line[17]==' '||!line[17]))
 135     {
 136       err = gpgsm_proxy_pinentry_notify (ctrl, line);
 137       if (err)
 138         log_error (_("failed to proxy %s inquiry to client\n"),
 139                    "PINENTRY_LAUNCHED");
 140       /* We do not pass errors to avoid breaking other code.  */
 141     }
 142   else
 143     log_error ("ignoring gpg-agent inquiry `%s'\n", line);
 144
 145   return 0;
 146 }
 147
 148
 149
 150 \f
 151 /* Call the agent to do a sign operation using the key identified by
 152    the hex string KEYGRIP. */
 153 int
 154 gpgsm_agent_pksign (ctrl_t ctrl, const char *keygrip, const char *desc,
 155                     unsigned char *digest, size_t digestlen, int digestalgo,
 156                     unsigned char **r_buf, size_t *r_buflen )
 157 {
 158   int rc, i;
 159   char *p, line[ASSUAN_LINELENGTH];
 160   membuf_t data;
 161   size_t len;
 162
 163   *r_buf = NULL;
 164   rc = start_agent (ctrl);
 165   if (rc)
 166     return rc;
 167
 168   if (digestlen*2 + 50 > DIM(line))
 169     return gpg_error (GPG_ERR_GENERAL);
 170
 171   rc = assuan_transact (agent_ctx, "RESET", NULL, NULL, NULL, NULL, NULL, NULL);
 172   if (rc)
 173     return rc;
 174
 175   snprintf (line, DIM(line)-1, "SIGKEY %s", keygrip);
 176   line[DIM(line)-1] = 0;
 177   rc = assuan_transact (agent_ctx, line, NULL, NULL, NULL, NULL, NULL, NULL);
 178   if (rc)
 179     return rc;
 180
 181   if (desc)
 182     {
 183       snprintf (line, DIM(line)-1, "SETKEYDESC %s", desc);
 184       line[DIM(line)-1] = 0;
 185       rc = assuan_transact (agent_ctx, line,
 186                             NULL, NULL, NULL, NULL, NULL, NULL);
 187       if (rc)
 188         return rc;
 189     }
 190
 191   sprintf (line, "SETHASH %d ", digestalgo);
 192   p = line + strlen (line);
 193   for (i=0; i < digestlen ; i++, p += 2 )
 194     sprintf (p, "%02X", digest[i]);
 195   rc = assuan_transact (agent_ctx, line, NULL, NULL, NULL, NULL, NULL, NULL);
 196   if (rc)
 197     return rc;
 198
 199   init_membuf (&data, 1024);
 200   rc = assuan_transact (agent_ctx, "PKSIGN",
 201                         membuf_data_cb, &data, default_inq_cb, ctrl,
 202                         NULL, NULL);
 203   if (rc)
 204     {
 205       xfree (get_membuf (&data, &len));
 206       return rc;
 207     }
 208   *r_buf = get_membuf (&data, r_buflen);
 209
 210   if (!gcry_sexp_canon_len (*r_buf, *r_buflen, NULL, NULL))
 211     {
 212       xfree (*r_buf); *r_buf = NULL;
 213       return gpg_error (GPG_ERR_INV_VALUE);
 214     }
 215
 216   return *r_buf? 0 : out_of_core ();
 217 }
 218
 219
 220 /* Call the scdaemon to do a sign operation using the key identified by
 221    the hex string KEYID. */
 222 int
 223 gpgsm_scd_pksign (ctrl_t ctrl, const char *keyid, const char *desc,
 224                   unsigned char *digest, size_t digestlen, int digestalgo,
 225                   unsigned char **r_buf, size_t *r_buflen )
 226 {
 227   int rc, i;
 228   char *p, line[ASSUAN_LINELENGTH];
 229   membuf_t data;
 230   size_t len;
 231   const char *hashopt;
 232   unsigned char *sigbuf;
 233   size_t sigbuflen;
 234
 235   (void)desc;
 236
 237   *r_buf = NULL;
 238
 239   switch(digestalgo)
 240     {
 241     case GCRY_MD_SHA1:  hashopt = "--hash=sha1"; break;
 242     case GCRY_MD_RMD160:hashopt = "--hash=rmd160"; break;
 243     case GCRY_MD_MD5:   hashopt = "--hash=md5"; break;
 244     case GCRY_MD_SHA256:hashopt = "--hash=sha256"; break;
 245     default:
 246       return gpg_error (GPG_ERR_DIGEST_ALGO);
 247     }
 248
 249   rc = start_agent (ctrl);
 250   if (rc)
 251     return rc;
 252
 253   if (digestlen*2 + 50 > DIM(line))
 254     return gpg_error (GPG_ERR_GENERAL);
 255
 256   p = stpcpy (line, "SCD SETDATA " );
 257   for (i=0; i < digestlen ; i++, p += 2 )
 258     sprintf (p, "%02X", digest[i]);
 259   rc = assuan_transact (agent_ctx, line, NULL, NULL, NULL, NULL, NULL, NULL);
 260   if (rc)
 261     return rc;
 262
 263   init_membuf (&data, 1024);
 264
 265   snprintf (line, DIM(line)-1, "SCD PKSIGN %s %s", hashopt, keyid);
 266   line[DIM(line)-1] = 0;
 267   rc = assuan_transact (agent_ctx, line,
 268                         membuf_data_cb, &data, default_inq_cb, ctrl,
 269                         NULL, NULL);
 270   if (rc)
 271     {
 272       xfree (get_membuf (&data, &len));
 273       return rc;
 274     }
 275   sigbuf = get_membuf (&data, &sigbuflen);
 276
 277   /* Create an S-expression from it which is formatted like this:
 278      "(7:sig-val(3:rsa(1:sSIGBUFLEN:SIGBUF)))" Fixme: If a card ever
 279      creates non-RSA keys we need to change things. */
 280   *r_buflen = 21 + 11 + sigbuflen + 4;
 281   p = xtrymalloc (*r_buflen);
 282   *r_buf = (unsigned char*)p;
 283   if (!p)
 284     {
 285       xfree (sigbuf);
 286       return 0;
 287     }
 288   p = stpcpy (p, "(7:sig-val(3:rsa(1:s" );
 289   sprintf (p, "%u:", (unsigned int)sigbuflen);
 290   p += strlen (p);
 291   memcpy (p, sigbuf, sigbuflen);
 292   p += sigbuflen;
 293   strcpy (p, ")))");
 294   xfree (sigbuf);
 295
 296   assert (gcry_sexp_canon_len (*r_buf, *r_buflen, NULL, NULL));
 297   return  0;
 298 }
 299
 300
 301
 302 \f
 303 /* Handle a CIPHERTEXT inquiry.  Note, we only send the data,
 304    assuan_transact talkes care of flushing and writing the end */
 305 static int
 306 inq_ciphertext_cb (void *opaque, const char *line)
 307 {
 308   struct cipher_parm_s *parm = opaque;
 309   int rc;
 310
 311   if (!strncmp (line, "CIPHERTEXT", 10) && (line[10]==' '||!line[10]))
 312     {
 313       assuan_begin_confidential (parm->ctx);
 314       rc = assuan_send_data (parm->ctx, parm->ciphertext, parm->ciphertextlen);
 315       assuan_end_confidential (parm->ctx);
 316     }
 317   else
 318     rc = default_inq_cb (parm->ctrl, line);
 319
 320   return rc;
 321 }
 322
 323
 324 /* Call the agent to do a decrypt operation using the key identified by
 325    the hex string KEYGRIP. */
 326 int
 327 gpgsm_agent_pkdecrypt (ctrl_t ctrl, const char *keygrip, const char *desc,
 328                        ksba_const_sexp_t ciphertext,
 329                        char **r_buf, size_t *r_buflen )
 330 {
 331   int rc;
 332   char line[ASSUAN_LINELENGTH];
 333    membuf_t data;
 334   struct cipher_parm_s cipher_parm;
 335   size_t n, len;
 336   char *p, *buf, *endp;
 337   size_t ciphertextlen;
 338
 339   if (!keygrip || strlen(keygrip) != 40 || !ciphertext || !r_buf || !r_buflen)
 340     return gpg_error (GPG_ERR_INV_VALUE);
 341   *r_buf = NULL;
 342
 343   ciphertextlen = gcry_sexp_canon_len (ciphertext, 0, NULL, NULL);
 344   if (!ciphertextlen)
 345     return gpg_error (GPG_ERR_INV_VALUE);
 346
 347   rc = start_agent (ctrl);
 348   if (rc)
 349     return rc;
 350
 351   rc = assuan_transact (agent_ctx, "RESET", NULL, NULL, NULL, NULL, NULL, NULL);
 352   if (rc)
 353     return rc;
 354
 355   assert ( DIM(line) >= 50 );
 356   snprintf (line, DIM(line)-1, "SETKEY %s", keygrip);
 357   line[DIM(line)-1] = 0;
 358   rc = assuan_transact (agent_ctx, line, NULL, NULL, NULL, NULL, NULL, NULL);
 359   if (rc)
 360     return rc;
 361
 362   if (desc)
 363     {
 364       snprintf (line, DIM(line)-1, "SETKEYDESC %s", desc);
 365       line[DIM(line)-1] = 0;
 366       rc = assuan_transact (agent_ctx, line,
 367                             NULL, NULL, NULL, NULL, NULL, NULL);
 368       if (rc)
 369         return rc;
 370     }
 371
 372   init_membuf (&data, 1024);
 373   cipher_parm.ctrl = ctrl;
 374   cipher_parm.ctx = agent_ctx;
 375   cipher_parm.ciphertext = ciphertext;
 376   cipher_parm.ciphertextlen = ciphertextlen;
 377   rc = assuan_transact (agent_ctx, "PKDECRYPT",
 378                         membuf_data_cb, &data,
 379                         inq_ciphertext_cb, &cipher_parm, NULL, NULL);
 380   if (rc)
 381     {
 382       xfree (get_membuf (&data, &len));
 383       return rc;
 384     }
 385
 386   put_membuf (&data, "", 1); /* Make sure it is 0 terminated. */
 387   buf = get_membuf (&data, &len);
 388   if (!buf)
 389     return gpg_error (GPG_ERR_ENOMEM);
 390   assert (len); /* (we forced Nul termination.)  */
 391
 392   if (*buf == '(')
 393     {
 394       if (len < 13 || memcmp (buf, "(5:value", 8) ) /* "(5:valueN:D)\0" */
 395         return gpg_error (GPG_ERR_INV_SEXP);
 396       len -= 11;   /* Count only the data of the second part. */
 397       p = buf + 8; /* Skip leading parenthesis and the value tag. */
 398     }
 399   else
 400     {
 401       /* For compatibility with older gpg-agents handle the old style
 402          incomplete S-exps. */
 403       len--;      /* Do not count the Nul. */
 404       p = buf;
 405     }
 406
 407   n = strtoul (p, &endp, 10);
 408   if (!n || *endp != ':')
 409     return gpg_error (GPG_ERR_INV_SEXP);
 410   endp++;
 411   if (endp-p+n > len)
 412     return gpg_error (GPG_ERR_INV_SEXP); /* Oops: Inconsistent S-Exp. */
 413
 414   memmove (buf, endp, n);
 415
 416   *r_buflen = n;
 417   *r_buf = buf;
 418   return 0;
 419 }
 420
 421
 422
 423
 424 \f
 425 /* Handle a KEYPARMS inquiry.  Note, we only send the data,
 426    assuan_transact takes care of flushing and writing the end */
 427 static int
 428 inq_genkey_parms (void *opaque, const char *line)
 429 {
 430   struct genkey_parm_s *parm = opaque;
 431   int rc;
 432
 433   if (!strncmp (line, "KEYPARAM", 8) && (line[8]==' '||!line[8]))
 434     {
 435       rc = assuan_send_data (parm->ctx, parm->sexp, parm->sexplen);
 436     }
 437   else
 438     rc = default_inq_cb (parm->ctrl, line);
 439
 440   return rc;
 441 }
 442
 443
 444 \f
 445 /* Call the agent to generate a newkey */
 446 int
 447 gpgsm_agent_genkey (ctrl_t ctrl,
 448                     ksba_const_sexp_t keyparms, ksba_sexp_t *r_pubkey)
 449 {
 450   int rc;
 451   struct genkey_parm_s gk_parm;
 452   membuf_t data;
 453   size_t len;
 454   unsigned char *buf;
 455
 456   *r_pubkey = NULL;
 457   rc = start_agent (ctrl);
 458   if (rc)
 459     return rc;
 460
 461   rc = assuan_transact (agent_ctx, "RESET", NULL, NULL, NULL, NULL, NULL, NULL);
 462   if (rc)
 463     return rc;
 464
 465   init_membuf (&data, 1024);
 466   gk_parm.ctrl = ctrl;
 467   gk_parm.ctx = agent_ctx;
 468   gk_parm.sexp = keyparms;
 469   gk_parm.sexplen = gcry_sexp_canon_len (keyparms, 0, NULL, NULL);
 470   if (!gk_parm.sexplen)
 471     return gpg_error (GPG_ERR_INV_VALUE);
 472   rc = assuan_transact (agent_ctx, "GENKEY",
 473                         membuf_data_cb, &data,
 474                         inq_genkey_parms, &gk_parm, NULL, NULL);
 475   if (rc)
 476     {
 477       xfree (get_membuf (&data, &len));
 478       return rc;
 479     }
 480   buf = get_membuf (&data, &len);
 481   if (!buf)
 482     return gpg_error (GPG_ERR_ENOMEM);
 483   if (!gcry_sexp_canon_len (buf, len, NULL, NULL))
 484     {
 485       xfree (buf);
 486       return gpg_error (GPG_ERR_INV_SEXP);
 487     }
 488   *r_pubkey = buf;
 489   return 0;
 490 }
 491
 492 \f
 493 /* Call the agent to read the public key part for a given keygrip.  If
 494    FROMCARD is true, the key is directly read from the current
 495    smartcard. In this case HEXKEYGRIP should be the keyID
 496    (e.g. OPENPGP.3). */
 497 int
 498 gpgsm_agent_readkey (ctrl_t ctrl, int fromcard, const char *hexkeygrip,
 499                      ksba_sexp_t *r_pubkey)
 500 {
 501   int rc;
 502   membuf_t data;
 503   size_t len;
 504   unsigned char *buf;
 505   char line[ASSUAN_LINELENGTH];
 506
 507   *r_pubkey = NULL;
 508   rc = start_agent (ctrl);
 509   if (rc)
 510     return rc;
 511
 512   rc = assuan_transact (agent_ctx, "RESET",NULL, NULL, NULL, NULL, NULL, NULL);
 513   if (rc)
 514     return rc;
 515
 516   snprintf (line, DIM(line)-1, "%sREADKEY %s",
 517             fromcard? "SCD ":"", hexkeygrip);
 518   line[DIM(line)-1] = 0;
 519
 520   init_membuf (&data, 1024);
 521   rc = assuan_transact (agent_ctx, line,
 522                         membuf_data_cb, &data,
 523                         default_inq_cb, ctrl, NULL, NULL);
 524   if (rc)
 525     {
 526       xfree (get_membuf (&data, &len));
 527       return rc;
 528     }
 529   buf = get_membuf (&data, &len);
 530   if (!buf)
 531     return gpg_error (GPG_ERR_ENOMEM);
 532   if (!gcry_sexp_canon_len (buf, len, NULL, NULL))
 533     {
 534       xfree (buf);
 535       return gpg_error (GPG_ERR_INV_SEXP);
 536     }
 537   *r_pubkey = buf;
 538   return 0;
 539 }
 540
 541 \f
 542
 543 static int
 544 istrusted_status_cb (void *opaque, const char *line)
 545 {
 546   struct rootca_flags_s *flags = opaque;
 547
 548   if (!strncmp (line, "TRUSTLISTFLAG", 13) && (line[13]==' ' || !line[13]))
 549     {
 550       for (line += 13; *line == ' '; line++)
 551         ;
 552       if (!strncmp (line, "relax", 5) && (line[5] == ' ' || !line[5]))
 553         flags->relax = 1;
 554       else if (!strncmp (line, "cm", 2) && (line[2] == ' ' || !line[2]))
 555         flags->chain_model = 1;
 556     }
 557   return 0;
 558 }
 559
 560
 561
 562 /* Ask the agent whether the certificate is in the list of trusted
 563    keys.  The certificate is either specified by the CERT object or by
 564    the fingerprint HEXFPR.  ROOTCA_FLAGS is guaranteed to be cleared
 565    on error. */
 566 int
 567 gpgsm_agent_istrusted (ctrl_t ctrl, ksba_cert_t cert, const char *hexfpr,
 568                        struct rootca_flags_s *rootca_flags)
 569 {
 570   int rc;
 571   char line[ASSUAN_LINELENGTH];
 572
 573   memset (rootca_flags, 0, sizeof *rootca_flags);
 574
 575   if (cert && hexfpr)
 576     return gpg_error (GPG_ERR_INV_ARG);
 577
 578   rc = start_agent (ctrl);
 579   if (rc)
 580     return rc;
 581
 582   if (hexfpr)
 583     {
 584       snprintf (line, DIM(line)-1, "ISTRUSTED %s", hexfpr);
 585       line[DIM(line)-1] = 0;
 586     }
 587   else
 588     {
 589       char *fpr;
 590
 591       fpr = gpgsm_get_fingerprint_hexstring (cert, GCRY_MD_SHA1);
 592       if (!fpr)
 593         {
 594           log_error ("error getting the fingerprint\n");
 595           return gpg_error (GPG_ERR_GENERAL);
 596         }
 597
 598       snprintf (line, DIM(line)-1, "ISTRUSTED %s", fpr);
 599       line[DIM(line)-1] = 0;
 600       xfree (fpr);
 601     }
 602
 603   rc = assuan_transact (agent_ctx, line, NULL, NULL, NULL, NULL,
 604                         istrusted_status_cb, rootca_flags);
 605   if (!rc)
 606     rootca_flags->valid = 1;
 607   return rc;
 608 }
 609
 610 /* Ask the agent to mark CERT as a trusted Root-CA one */
 611 int
 612 gpgsm_agent_marktrusted (ctrl_t ctrl, ksba_cert_t cert)
 613 {
 614   int rc;
 615   char *fpr, *dn, *dnfmt;
 616   char line[ASSUAN_LINELENGTH];
 617
 618   rc = start_agent (ctrl);
 619   if (rc)
 620     return rc;
 621
 622   fpr = gpgsm_get_fingerprint_hexstring (cert, GCRY_MD_SHA1);
 623   if (!fpr)
 624     {
 625       log_error ("error getting the fingerprint\n");
 626       return gpg_error (GPG_ERR_GENERAL);
 627     }
 628
 629   dn = ksba_cert_get_issuer (cert, 0);
 630   if (!dn)
 631     {
 632       xfree (fpr);
 633       return gpg_error (GPG_ERR_GENERAL);
 634     }
 635   dnfmt = gpgsm_format_name2 (dn, 0);
 636   xfree (dn);
 637   if (!dnfmt)
 638     return gpg_error_from_syserror ();
 639   snprintf (line, DIM(line)-1, "MARKTRUSTED %s S %s", fpr, dnfmt);
 640   line[DIM(line)-1] = 0;
 641   ksba_free (dnfmt);
 642   xfree (fpr);
 643
 644   rc = assuan_transact (agent_ctx, line, NULL, NULL,
 645                         default_inq_cb, ctrl, NULL, NULL);
 646   return rc;
 647 }
 648
 649
 650 \f
 651 /* Ask the agent whether the a corresponding secret key is available
 652    for the given keygrip */
 653 int
 654 gpgsm_agent_havekey (ctrl_t ctrl, const char *hexkeygrip)
 655 {
 656   int rc;
 657   char line[ASSUAN_LINELENGTH];
 658
 659   rc = start_agent (ctrl);
 660   if (rc)
 661     return rc;
 662
 663   if (!hexkeygrip || strlen (hexkeygrip) != 40)
 664     return gpg_error (GPG_ERR_INV_VALUE);
 665
 666   snprintf (line, DIM(line)-1, "HAVEKEY %s", hexkeygrip);
 667   line[DIM(line)-1] = 0;
 668
 669   rc = assuan_transact (agent_ctx, line, NULL, NULL, NULL, NULL, NULL, NULL);
 670   return rc;
 671 }
 672
 673 \f
 674 static int
 675 learn_status_cb (void *opaque, const char *line)
 676 {
 677   struct learn_parm_s *parm = opaque;
 678
 679   /* Pass progress data to the caller.  */
 680   if (!strncmp (line, "PROGRESS", 8) && (line[8]==' ' || !line[8]))
 681     {
 682       if (parm->ctrl)
 683         {
 684           for (line += 8; *line == ' '; line++)
 685             ;
 686           if (gpgsm_status (parm->ctrl, STATUS_PROGRESS, line))
 687             return gpg_error (GPG_ERR_ASS_CANCELED);
 688         }
 689     }
 690   return 0;
 691 }
 692
 693 static int
 694 learn_cb (void *opaque, const void *buffer, size_t length)
 695 {
 696   struct learn_parm_s *parm = opaque;
 697   size_t len;
 698   char *buf;
 699   ksba_cert_t cert;
 700   int rc;
 701
 702   if (parm->error)
 703     return 0;
 704
 705   if (buffer)
 706     {
 707       put_membuf (parm->data, buffer, length);
 708       return 0;
 709     }
 710   /* END encountered - process what we have */
 711   buf = get_membuf (parm->data, &len);
 712   if (!buf)
 713     {
 714       parm->error = gpg_error (GPG_ERR_ENOMEM);
 715       return 0;
 716     }
 717
 718   if (gpgsm_status (parm->ctrl, STATUS_PROGRESS, "learncard C 0 0"))
 719     return gpg_error (GPG_ERR_ASS_CANCELED);
 720
 721   /* FIXME: this should go into import.c */
 722   rc = ksba_cert_new (&cert);
 723   if (rc)
 724     {
 725       parm->error = rc;
 726       return 0;
 727     }
 728   rc = ksba_cert_init_from_mem (cert, buf, len);
 729   if (rc)
 730     {
 731       log_error ("failed to parse a certificate: %s\n", gpg_strerror (rc));
 732       ksba_cert_release (cert);
 733       parm->error = rc;
 734       return 0;
 735     }
 736
 737   rc = gpgsm_basic_cert_check (parm->ctrl, cert);
 738   if (gpg_err_code (rc) == GPG_ERR_MISSING_CERT)
 739     { /* For later use we store it in the ephemeral database. */
 740       log_info ("issuer certificate missing - storing as ephemeral\n");
 741       keydb_store_cert (cert, 1, NULL);
 742     }
 743   else if (rc)
 744     log_error ("invalid certificate: %s\n", gpg_strerror (rc));
 745   else
 746     {
 747       int existed;
 748
 749       if (!keydb_store_cert (cert, 0, &existed))
 750         {
 751           if (opt.verbose > 1 && existed)
 752             log_info ("certificate already in DB\n");
 753           else if (opt.verbose && !existed)
 754             log_info ("certificate imported\n");
 755         }
 756     }
 757
 758   ksba_cert_release (cert);
 759   init_membuf (parm->data, 4096);
 760   return 0;
 761 }
 762
 763 /* Call the agent to learn about a smartcard */
 764 int
 765 gpgsm_agent_learn (ctrl_t ctrl)
 766 {
 767   int rc;
 768   struct learn_parm_s learn_parm;
 769   membuf_t data;
 770   size_t len;
 771
 772   rc = start_agent (ctrl);
 773   if (rc)
 774     return rc;
 775
 776   init_membuf (&data, 4096);
 777   learn_parm.error = 0;
 778   learn_parm.ctrl = ctrl;
 779   learn_parm.ctx = agent_ctx;
 780   learn_parm.data = &data;
 781   rc = assuan_transact (agent_ctx, "LEARN --send",
 782                         learn_cb, &learn_parm,
 783                         NULL, NULL,
 784                         learn_status_cb, &learn_parm);
 785   xfree (get_membuf (&data, &len));
 786   if (rc)
 787     return rc;
 788   return learn_parm.error;
 789 }
 790
 791 \f
 792 /* Ask the agent to change the passphrase of the key identified by
 793    HEXKEYGRIP. If DESC is not NULL, display instead of the default
 794    description message. */
 795 int
 796 gpgsm_agent_passwd (ctrl_t ctrl, const char *hexkeygrip, const char *desc)
 797 {
 798   int rc;
 799   char line[ASSUAN_LINELENGTH];
 800
 801   rc = start_agent (ctrl);
 802   if (rc)
 803     return rc;
 804
 805   if (!hexkeygrip || strlen (hexkeygrip) != 40)
 806     return gpg_error (GPG_ERR_INV_VALUE);
 807
 808   if (desc)
 809     {
 810       snprintf (line, DIM(line)-1, "SETKEYDESC %s", desc);
 811       line[DIM(line)-1] = 0;
 812       rc = assuan_transact (agent_ctx, line,
 813                             NULL, NULL, NULL, NULL, NULL, NULL);
 814       if (rc)
 815         return rc;
 816     }
 817
 818   snprintf (line, DIM(line)-1, "PASSWD %s", hexkeygrip);
 819   line[DIM(line)-1] = 0;
 820
 821   rc = assuan_transact (agent_ctx, line, NULL, NULL,
 822                         default_inq_cb, ctrl, NULL, NULL);
 823   return rc;
 824 }
 825
 826
 827 \f
 828 /* Ask the agent to pop up a confirmation dialog with the text DESC
 829    and an okay and cancel button.  */
 830 gpg_error_t
 831 gpgsm_agent_get_confirmation (ctrl_t ctrl, const char *desc)
 832 {
 833   int rc;
 834   char line[ASSUAN_LINELENGTH];
 835
 836   rc = start_agent (ctrl);
 837   if (rc)
 838     return rc;
 839
 840   snprintf (line, DIM(line)-1, "GET_CONFIRMATION %s", desc);
 841   line[DIM(line)-1] = 0;
 842
 843   rc = assuan_transact (agent_ctx, line, NULL, NULL,
 844                         default_inq_cb, ctrl, NULL, NULL);
 845   return rc;
 846 }
 847
 848
 849 \f
 850 /* Return 0 if the agent is alive.  This is useful to make sure that
 851    an agent has been started. */
 852 gpg_error_t
 853 gpgsm_agent_send_nop (ctrl_t ctrl)
 854 {
 855   int rc;
 856
 857   rc = start_agent (ctrl);
 858   if (!rc)
 859     rc = assuan_transact (agent_ctx, "NOP",
 860                           NULL, NULL, NULL, NULL, NULL, NULL);
 861   return rc;
 862 }
 863
 864
 865 \f
 866 static int
 867 keyinfo_status_cb (void *opaque, const char *line)
 868 {
 869   char **serialno = opaque;
 870   const char *s, *s2;
 871
 872   if (!strncmp (line, "KEYINFO ", 8) && !*serialno)
 873     {
 874       s = strchr (line+8, ' ');
 875       if (s && s[1] == 'T' && s[2] == ' ' && s[3])
 876         {
 877           s += 3;
 878           s2 = strchr (s, ' ');
 879           if ( s2 > s )
 880             {
 881               *serialno = xtrymalloc ((s2 - s)+1);
 882               if (*serialno)
 883                 {
 884                   memcpy (*serialno, s, s2 - s);
 885                   (*serialno)[s2 - s] = 0;
 886                 }
 887             }
 888         }
 889     }
 890   return 0;
 891 }
 892
 893 /* Return the serial number for a secret key.  If the returned serial
 894    number is NULL, the key is not stored on a smartcard.  Caller needs
 895    to free R_SERIALNO.  */
 896 gpg_error_t
 897 gpgsm_agent_keyinfo (ctrl_t ctrl, const char *hexkeygrip, char **r_serialno)
 898 {
 899   gpg_error_t err;
 900   char line[ASSUAN_LINELENGTH];
 901   char *serialno = NULL;
 902
 903   *r_serialno = NULL;
 904
 905   err = start_agent (ctrl);
 906   if (err)
 907     return err;
 908
 909   if (!hexkeygrip || strlen (hexkeygrip) != 40)
 910     return gpg_error (GPG_ERR_INV_VALUE);
 911
 912   snprintf (line, DIM(line)-1, "KEYINFO %s", hexkeygrip);
 913   line[DIM(line)-1] = 0;
 914
 915   err = assuan_transact (agent_ctx, line, NULL, NULL, NULL, NULL,
 916                          keyinfo_status_cb, &serialno);
 917   if (!err && serialno)
 918     {
 919       /* Sanity check for bad characters.  */
 920       if (strpbrk (serialno, ":\n\r"))
 921         err = GPG_ERR_INV_VALUE;
 922     }
 923   if (err)
 924     xfree (serialno);
 925   else
 926     *r_serialno = serialno;
 927   return err;
 928 }
 929