libpwmd.c

   1 /* vim:tw=78:ts=8:sw=4:set ft=c:  */
   2 /*
   3     Copyright (C) 2006-2008 Ben Kibbey <bjk@luxsci.net>
   4
   5     This program is free software; you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation; either version 2 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License
  16     along with this program; if not, write to the Free Software
  17     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02110-1301  USA
  18 */
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <unistd.h>
  22 #include <err.h>
  23 #include <errno.h>
  24 #include <ctype.h>
  25 #include <string.h>
  26 #include <sys/socket.h>
  27 #include <sys/un.h>
  28 #include <signal.h>
  29 #include <stdarg.h>
  30 #include <string.h>
  31 #include <sys/wait.h>
  32 #include <fcntl.h>
  33 #include <pwd.h>
  34 #include <time.h>
  35 #include <sys/types.h>
  36 #include <limits.h>
  37 #include <sys/select.h>
  38 #include <libpwmd.h>
  39
  40 #ifdef HAVE_CONFIG_H
  41 #include <config.h>
  42 #endif
  43
  44 #ifdef WITH_LIBPTH
  45 #include <pth.h>
  46 #endif
  47
  48 #ifdef HAVE_ASSUAN_H
  49 #include <assuan.h>
  50 #endif
  51
  52 #ifdef HAVE_SETLOCALE
  53 #include <locale.h>
  54 #endif
  55
  56 #include "gettext.h"
  57 #define N_(msgid)       dgettext("libpwmd", msgid)
  58
  59 #ifndef MEM_DEBUG
  60 #include "mem.h"
  61 #else
  62 #define xfree           free
  63 #define xrealloc        realloc
  64 #define xmalloc         malloc
  65 #define xstrdup         strdup
  66 #define xcalloc         calloc
  67 #endif
  68
  69 #include "types.h"
  70
  71 #ifdef USE_PINENTRY
  72 static pwm_t *gpwm;
  73 static int gelapsed, gtimeout;
  74 static gpg_error_t pinentry_command(pwm_t *pwm, char **result, const char *cmd);
  75 static gpg_error_t global_error;
  76 #endif
  77
  78 const char *pwmd_strerror(gpg_error_t e)
  79 {
  80     gpg_err_code_t code = gpg_err_code(e);
  81
  82     if (code >= GPG_ERR_USER_1 && code < gpg_err_code(EPWMD_MAX)) {
  83         switch (code) {
  84             case GPG_ERR_USER_1:
  85             default:
  86                 return N_("Unknown error");
  87             case GPG_ERR_USER_2:
  88                 return N_("No cache slots available");
  89             case GPG_ERR_USER_3:
  90                 return N_("Recursion loop");
  91             case GPG_ERR_USER_4:
  92                 return N_("No file is open");
  93             case GPG_ERR_USER_5:
  94                 return N_("General LibXML error");
  95             case GPG_ERR_USER_6:
  96                 return N_("File modified");
  97         }
  98     }
  99
 100     return gpg_strerror(e);
 101 }
 102
 103 gpg_error_t pwmd_init()
 104 {
 105     static int initialized;
 106
 107     if (initialized)
 108         return 0;
 109
 110 #ifdef ENABLE_NLS
 111     bindtextdomain("libpwmd", LOCALEDIR);
 112 #endif
 113     gpg_err_init();
 114     assuan_set_malloc_hooks(xmalloc, xrealloc, xfree);
 115     assuan_set_assuan_err_source(GPG_ERR_SOURCE_DEFAULT);
 116     initialized = 1;
 117     return 0;
 118 }
 119
 120 pwm_t *pwmd_connect(const char *path, gpg_error_t *error)
 121 {
 122     pwm_t *pwm = NULL;
 123     char *socketpath = NULL;
 124     time_t now;
 125     struct passwd *pw;
 126     assuan_context_t ctx;
 127     int rc, n;
 128     int active[2];
 129
 130     if (!path) {
 131         pw = getpwuid(getuid());
 132         socketpath = (char *)xmalloc(strlen(pw->pw_dir) + strlen("/.pwmd/socket") + 1);
 133         sprintf(socketpath, "%s/.pwmd/socket", pw->pw_dir);
 134     }
 135     else
 136         socketpath = xstrdup(path);
 137
 138     rc = assuan_socket_connect_ext(&ctx, socketpath, -1, 0);
 139     xfree(socketpath);
 140
 141     if (rc) {
 142         *error = rc;
 143         return NULL;
 144     }
 145
 146     n = assuan_get_active_fds(ctx, 0, active, sizeof(active));
 147
 148     if ((pwm = (pwm_t *)xcalloc(1, sizeof(pwm_t))) == NULL) {
 149         *error = gpg_error_from_errno(errno);
 150         assuan_disconnect(ctx);
 151         return NULL;
 152     }
 153
 154     pwm->fd = n <= 0 ? -1 : dup(active[0]);
 155
 156     if (pwm->fd != -1)
 157         fcntl(pwm->fd, F_SETFL, O_NONBLOCK);
 158
 159     pwm->ctx = ctx;
 160 #ifdef USE_PINENTRY
 161     pwm->pid = -1;
 162     pwm->pinentry_tries = 3;
 163 #endif
 164     time(&now);
 165     srandom(now);
 166     *error = 0;
 167     return pwm;
 168 }
 169
 170 gpg_error_t pwmd_pending_line(pwm_t *pwm, char **line, size_t *len)
 171 {
 172     if (!pwm)
 173         return GPG_ERR_INV_ARG;
 174
 175     if (assuan_pending_line(pwm->ctx))
 176         return assuan_read_line(pwm->ctx, line, len);
 177
 178     return GPG_ERR_NO_DATA;
 179 }
 180
 181 void pwmd_close(pwm_t *pwm)
 182 {
 183     if (!pwm)
 184         return;
 185
 186     if (pwm->ctx)
 187         assuan_disconnect(pwm->ctx);
 188
 189     if (pwm->password)
 190         xfree(pwm->password);
 191
 192     if (pwm->title)
 193         xfree(pwm->title);
 194
 195     if (pwm->desc)
 196         xfree(pwm->desc);
 197
 198     if (pwm->prompt)
 199         xfree(pwm->prompt);
 200
 201     if (pwm->pinentry_tty)
 202         xfree(pwm->pinentry_tty);
 203
 204     if (pwm->pinentry_display)
 205         xfree(pwm->pinentry_display);
 206
 207     if (pwm->pinentry_term)
 208         xfree(pwm->pinentry_term);
 209
 210     if (pwm->filename)
 211         xfree(pwm->filename);
 212
 213     xfree(pwm);
 214 }
 215
 216 static int mem_realloc_cb(void *data, const void *buffer, size_t len)
 217 {
 218     membuf_t *mem = (membuf_t *)data;
 219     void *p;
 220
 221     if (!buffer)
 222         return 0;
 223
 224     if ((p = xrealloc(mem->buf, mem->len + len)) == NULL)
 225         return 1;
 226
 227     mem->buf = p;
 228     memcpy((char *)mem->buf + mem->len, buffer, len);
 229     mem->len += len;
 230     return 0;
 231 }
 232
 233 void pwmd_free_result(void *data)
 234 {
 235     xfree(data);
 236 }
 237
 238 static int _inquire_cb(void *data, const char *keyword)
 239 {
 240     pwm_t *pwm = (pwm_t *)data;
 241     gpg_error_t rc = 0;
 242     int flags = fcntl(pwm->fd, F_GETFL);
 243
 244     /* Shouldn't get this far without a callback. */
 245     if (!pwm->inquire_func)
 246         return GPG_ERR_INV_ARG;
 247
 248     /*
 249      * Since the socket file descriptor is probably set to non-blocking, set to
 250      * blocking to prevent GPG_ERR_EAGAIN errors. This should be fixes when
 251      * asynchronous INQUIRE is supported by either libassuan or a later
 252      * libpwmd.
 253      */
 254     fcntl(pwm->fd, F_SETFL, 0);
 255
 256     for (;;) {
 257         char *result = NULL;
 258         size_t len;
 259         gpg_error_t arc;
 260
 261         rc = pwm->inquire_func(pwm->inquire_data, keyword, rc, &result, &len);
 262         rc = gpg_err_code(rc);
 263
 264         if (rc == GPG_ERR_EOF || !rc) {
 265             if (len <= 0 || !result || !*result) {
 266                 rc = 0;
 267                 break;
 268             }
 269
 270             arc = assuan_send_data(pwm->ctx, result, len);
 271
 272             if (rc == GPG_ERR_EOF) {
 273                 rc = arc;
 274                 break;
 275             }
 276
 277             rc = arc;
 278         }
 279         else if (rc)
 280             break;
 281     }
 282
 283     fcntl(pwm->fd, F_SETFL, flags);
 284     return rc;
 285 }
 286
 287 gpg_error_t pwmd_finalize(pwm_t *pwm)
 288 {
 289     if (!pwm || pwm->fd < 0)
 290         return GPG_ERR_INV_ARG;
 291
 292     pwm->state = ASYNC_INIT;
 293     pwm->ntries = 0;
 294     pwm->is_open_cmd = 0;
 295     return 0;
 296 }
 297
 298 static gpg_error_t do_nb_command(pwm_t *pwm, const char *cmd, const char *arg)
 299 {
 300     char *buf;
 301     gpg_error_t rc;
 302     size_t len = strlen(cmd) + 2;
 303
 304     len += arg ? strlen(arg) : 0;
 305
 306     if (pwm->state != ASYNC_INIT)
 307         return GPG_ERR_UNEXPECTED;
 308
 309     buf = (char *)xmalloc(len);
 310
 311     if (!buf) {
 312         rc = gpg_error_from_errno(ENOMEM);
 313         goto fail;
 314     }
 315
 316     snprintf(buf, len, "%s %s", cmd, arg ? arg : "");
 317     rc = assuan_write_line(pwm->ctx, buf);
 318     xfree(buf);
 319
 320     if (!rc)
 321         pwm->state = ASYNC_PROCESS;
 322
 323 fail:
 324     return rc;
 325 }
 326
 327 gpg_error_t pwmd_open_async(pwm_t *pwm, const char *filename)
 328 {
 329     if (!pwm || !filename)
 330         return GPG_ERR_INV_ARG;
 331
 332     /* For pinentry retries. */
 333     if (!pwm->is_open_cmd) {
 334         if (pwm->filename)
 335             xfree(pwm->filename);
 336
 337         pwm->filename = xstrdup(filename);
 338     }
 339
 340     pwm->is_open_cmd = 1;
 341     return do_nb_command(pwm, "OPEN", filename);
 342 }
 343
 344 gpg_error_t pwmd_save_async(pwm_t *pwm)
 345 {
 346     if (!pwm)
 347         return GPG_ERR_INV_ARG;
 348
 349     return do_nb_command(pwm, "SAVE", NULL);
 350 }
 351
 352 static gpg_error_t parse_assuan_line(pwm_t *pwm)
 353 {
 354     gpg_error_t rc;
 355     char *line;
 356     size_t len;
 357
 358     rc = assuan_read_line(pwm->ctx, &line, &len);
 359
 360     if (!rc) {
 361         if (line[0] == 'O' && line[1] == 'K' &&
 362                 (line[2] == 0 || line[2] == ' ')) {
 363             pwm->state = ASYNC_DONE;
 364         }
 365         else if (line[0] == '#') {
 366         }
 367         else if (line[0] == 'S' && (line[1] == 0 || line[1] == ' ')) {
 368             if (pwm->status_func) {
 369                 pwm->status_func(pwm->status_data,
 370                         line[1] == 0 ? line+1 : line+2);
 371             }
 372         }
 373         else if (line[0] == 'E' && line[1] == 'R' && line[2] == 'R' &&
 374                 (line[3] == 0 || line[3] == ' ')) {
 375             line += 4;
 376             rc = atoi(line);
 377             pwm->state = ASYNC_DONE;
 378         }
 379     }
 380
 381     return rc;
 382 }
 383
 384 pwmd_async_t pwmd_process(pwm_t *pwm, gpg_error_t *rc)
 385 {
 386     fd_set rfds;
 387     int n;
 388     struct timeval tv = {0, 0};
 389
 390     *rc = 0;
 391
 392     if (!pwm || pwm->fd < 0) {
 393         *rc = GPG_ERR_INV_ARG;
 394         return ASYNC_DONE;
 395     }
 396     else if (pwm->state == ASYNC_DONE)
 397         return pwm->state;
 398     else if (pwm->state == ASYNC_INIT) {
 399         *rc = GPG_ERR_UNEXPECTED;
 400         return ASYNC_DONE;
 401     }
 402
 403     FD_ZERO(&rfds);
 404     FD_SET(pwm->fd, &rfds);
 405 #ifdef WITH_LIBPTH
 406     n = pth_select(pwm->fd+1, &rfds, NULL, NULL, &tv);
 407 #else
 408     n = select(pwm->fd+1, &rfds, NULL, NULL, &tv);
 409 #endif
 410
 411     if (n > 0) {
 412         if (FD_ISSET(pwm->fd, &rfds))
 413             *rc = parse_assuan_line(pwm);
 414     }
 415
 416     while (!*rc && assuan_pending_line(pwm->ctx))
 417         *rc = parse_assuan_line(pwm);
 418
 419     if (pwm->is_open_cmd && gpg_err_code(*rc) == EPWMD_BADKEY &&
 420             ++pwm->ntries < pwm->pinentry_tries) {
 421         pwm->state = ASYNC_INIT;
 422         *rc = pwmd_open_async(pwm, pwm->filename);
 423     }
 424
 425     return pwm->state;
 426 }
 427
 428 static gpg_error_t assuan_command(pwm_t *pwm, assuan_context_t ctx,
 429         char **result, const char *cmd)
 430 {
 431     membuf_t data;
 432     gpg_error_t rc;
 433
 434     data.len = 0;
 435     data.buf = NULL;
 436
 437     rc = assuan_transact(ctx, cmd, mem_realloc_cb, &data, _inquire_cb, pwm,
 438             pwm->status_func, pwm->status_data);
 439
 440     if (rc) {
 441         if (data.buf) {
 442             xfree(data.buf);
 443             data.buf = NULL;
 444         }
 445     }
 446     else {
 447         if (data.buf) {
 448             mem_realloc_cb(&data, "", 1);
 449             *result = (char *)data.buf;
 450         }
 451     }
 452
 453     return gpg_err_code(rc);
 454 }
 455
 456 gpg_error_t pwmd_inquire(pwm_t *pwm, const char *cmd, pwmd_inquire_fn fn,
 457         void *data)
 458 {
 459     if (!pwm || !cmd || !fn)
 460         return GPG_ERR_INV_ARG;
 461
 462     pwm->inquire_func = fn;
 463     pwm->inquire_data = data;
 464     return assuan_command(pwm, pwm->ctx, NULL, cmd);
 465 }
 466
 467 gpg_error_t pwmd_terminate_pinentry(pwm_t *pwm)
 468 {
 469 #ifndef USE_PINENTRY
 470     return GPG_ERR_NOT_IMPLEMENTED;
 471 #else
 472     if (!pwm || pwm->pid == -1)
 473         return GPG_ERR_INV_ARG;
 474
 475     if (kill(pwm->pid, 0) == 0) {
 476         if (kill(pwm->pid, SIGTERM) == -1) {
 477             if (kill(pwm->pid, SIGKILL) == -1)
 478                 return gpg_error_from_errno(errno);
 479         }
 480
 481         pwm->pin_error = GPG_ERR_TIMEOUT;
 482     }
 483     else
 484         return gpg_error_from_errno(errno);
 485
 486     return 0;
 487 #endif
 488 }
 489
 490 #ifdef USE_PINENTRY
 491 static gpg_error_t set_pinentry_strings(pwm_t *pwm, int which)
 492 {
 493     char *buf;
 494     char tmp[ASSUAN_LINELENGTH];
 495     gpg_error_t error;
 496
 497     if (!pwm->title)
 498         pwm->title = xstrdup(N_("LibPWMD"));
 499
 500     if (!pwm->prompt)
 501         pwm->prompt = xstrdup(N_("Password:"));
 502
 503     if (!pwm->desc && !which)
 504         pwm->desc = xstrdup(N_("Enter a password."));
 505
 506     if (which == 1) {
 507         snprintf(tmp, sizeof(tmp), "SETERROR %s", N_("Invalid password, please try again."));
 508         buf = xstrdup(tmp);
 509     }
 510     else if (which == 2) {
 511         snprintf(tmp, sizeof(tmp), "SETERROR %s", N_("Please type the password again for confirmation."));
 512         buf = xstrdup(tmp);
 513     }
 514     else {
 515         buf = (char *)xmalloc(strlen("SETERROR ") + strlen(pwm->desc) + 1);
 516         sprintf(buf, "SETERROR %s", pwm->desc);
 517     }
 518
 519     error = pinentry_command(pwm, NULL, buf);
 520     xfree(buf);
 521
 522     if (error)
 523         return error;
 524
 525     buf = (char *)xmalloc(strlen("SETPROMPT ") + strlen(pwm->prompt) + 1);
 526     sprintf(buf, "SETPROMPT %s", pwm->prompt);
 527     error = pinentry_command(pwm, NULL, buf);
 528     xfree(buf);
 529
 530     if (error)
 531         return error;
 532
 533     buf = (char *)xmalloc(strlen("SETDESC ") + strlen(pwm->title) + 1);
 534     sprintf(buf, "SETDESC %s", pwm->title);
 535     error = pinentry_command(pwm, NULL, buf);
 536     xfree(buf);
 537     return error;
 538 }
 539
 540 static void update_pinentry_settings(pwm_t *pwm)
 541 {
 542     FILE *fp;
 543     char buf[LINE_MAX];
 544     struct passwd *pw = getpwuid(getuid());
 545     char *p;
 546
 547     snprintf(buf, sizeof(buf), "%s/.pwmd/pinentry.conf", pw->pw_dir);
 548
 549     if ((fp = fopen(buf, "r")) == NULL)
 550         return;
 551
 552     while ((p = fgets(buf, sizeof(buf), fp)) != NULL) {
 553         char name[32], val[256];
 554
 555         if (sscanf(p, " %31[a-zA-Z] = %255s", name, val) != 2)
 556             continue;
 557
 558         if (strcasecmp(name, "TTYNAME") == 0) {
 559             xfree(pwm->pinentry_tty);
 560             pwm->pinentry_tty = xstrdup(val);
 561         }
 562         else if (strcasecmp(name, "TTYTYPE") == 0) {
 563             xfree(pwm->pinentry_term);
 564             pwm->pinentry_term = xstrdup(val);
 565         }
 566         else if (strcasecmp(name, "DISPLAY") == 0) {
 567             xfree(pwm->pinentry_display);
 568             pwm->pinentry_display = xstrdup(val);
 569         }
 570         else if (strcasecmp(name, "PATH") == 0) {
 571             xfree(pwm->pinentry_path);
 572             pwm->pinentry_path = xstrdup(val);
 573         }
 574     }
 575
 576     fclose(fp);
 577 }
 578
 579 static gpg_error_t launch_pinentry(pwm_t *pwm)
 580 {
 581     int rc;
 582     assuan_context_t ctx;
 583     int child_list[] = {-1};
 584     char *display = getenv("DISPLAY");
 585     const char *argv[6];
 586     int have_display = 0;
 587     char *tty = NULL;
 588
 589     update_pinentry_settings(pwm);
 590
 591     if (pwm->pinentry_display || display)
 592         have_display = 1;
 593     else {
 594         tty = pwm->pinentry_tty ? pwm->pinentry_tty : ttyname(STDOUT_FILENO);
 595
 596         if (!tty)
 597             return gpg_error_from_errno(errno);
 598     }
 599
 600     if (!have_display && !tty)
 601         return GPG_ERR_ENOTTY;
 602
 603     argv[0] = "pinentry";
 604     argv[1] = have_display ? "--display" : "--ttyname";
 605     argv[2] = have_display ? pwm->pinentry_display ? pwm->pinentry_display : display : tty;
 606     argv[3] = NULL;
 607
 608     if (!have_display) {
 609         argv[3] = "--ttytype";
 610         argv[4] = pwm->pinentry_term ? pwm->pinentry_term : getenv("TERM");
 611         argv[5] = NULL;
 612     }
 613
 614     rc = assuan_pipe_connect(&ctx, pwm->pinentry_path ? pwm->pinentry_path : PINENTRY_PATH, argv, child_list);
 615
 616     if (rc)
 617         return rc;
 618
 619     pwm->pid = assuan_get_pid(ctx);
 620     pwm->pctx = ctx;
 621     return set_pinentry_strings(pwm, 0);
 622 }
 623
 624 static gpg_error_t pinentry_command(pwm_t *pwm, char **result, const char *cmd)
 625 {
 626     gpg_error_t n;
 627
 628     if (!pwm->pctx) {
 629         n = launch_pinentry(pwm);
 630
 631         if (n)
 632             return n;
 633     }
 634
 635     return assuan_command(pwm, pwm->pctx, result, cmd);
 636 }
 637
 638 static void pinentry_disconnect(pwm_t *pwm)
 639 {
 640     if (pwm->pctx)
 641         assuan_disconnect(pwm->pctx);
 642
 643     pwm->pctx = NULL;
 644     pwm->pid = -1;
 645 }
 646
 647 /*
 648  * Only called from a child process.
 649  */
 650 static void catchsig(int sig)
 651 {
 652     switch (sig) {
 653         case SIGALRM:
 654             if (gelapsed++ >= gtimeout) {
 655                 global_error = pwmd_terminate_pinentry(gpwm);
 656
 657                 if (!global_error)
 658                     global_error = GPG_ERR_TIMEOUT;
 659
 660                 break;
 661             }
 662
 663             alarm(1);
 664             break;
 665         default:
 666             break;
 667     }
 668 }
 669
 670 /*
 671  * Borrowed from libassuan.
 672  */
 673 static char *percent_escape(const char *atext)
 674 {
 675     const unsigned char *s;
 676     int len = strlen(atext) * 3 + 1;
 677     char *buf = (char *)xmalloc(len), *p = buf;
 678
 679     if (!buf)
 680         return NULL;
 681
 682     for (s=(const unsigned char *)atext; *s; s++) {
 683         if (*s < ' ') {
 684             sprintf (p, "%%%02X", *s);
 685             p += 3;
 686         }
 687         else
 688             *p++ = *s;
 689     }
 690
 691     *p = 0;
 692     return buf;
 693 }
 694 #endif
 695
 696 static gpg_error_t send_command(pwm_t *pwm, char **result, const char *cmd)
 697 {
 698     if (!cmd)
 699         return GPG_ERR_INV_ARG;
 700
 701     return assuan_command(pwm, pwm->ctx, result, cmd);
 702 }
 703
 704 /*
 705  * Avoid sending the BYE command here. libassuan will close the file
 706  * descriptor and release the assuan context. Use pwmd_close() instead.
 707  */
 708 gpg_error_t pwmd_command(pwm_t *pwm, char **result, const char *cmd, ...)
 709 {
 710     va_list ap;
 711     char *buf;
 712     size_t len;
 713     gpg_error_t error;
 714
 715     if (!pwm || !cmd)
 716         return GPG_ERR_INV_ARG;
 717
 718     *result = NULL;
 719     va_start(ap, cmd);
 720     /*
 721      * C99 allows the dst pointer to be null which will calculate the length
 722      * of the result and return it.
 723      */
 724     len = vsnprintf(NULL, 0, cmd, ap);
 725     buf = (char *)xmalloc(len + 1);
 726     len = vsnprintf(buf, len + 1, cmd, ap);
 727     va_end(ap);
 728     error = send_command(pwm, result, buf);
 729     xfree(buf);
 730     return error;
 731 }
 732
 733 #ifdef USE_PINENTRY
 734 static gpg_error_t do_getpin(pwm_t *pwm, char **result)
 735 {
 736     if (gtimeout) {
 737         signal(SIGALRM, catchsig);
 738         alarm(1);
 739     }
 740
 741     *result = NULL;
 742     return pinentry_command(pwm, result, "GETPIN");
 743 }
 744
 745 static gpg_error_t getpin(pwm_t *pwm, char **result, int *try_n, int which)
 746 {
 747     int pin_try = *try_n;
 748     gpg_error_t error;
 749
 750 getpin_again:
 751     *try_n = pin_try;
 752
 753     if (pin_try == -1) {
 754         error = set_pinentry_strings(pwm, which);
 755
 756         if (error) {
 757             pinentry_disconnect(pwm);
 758             return error;
 759         }
 760     }
 761     else {
 762         if (pwm->pinentry_tries-1 != pin_try) {
 763             error = set_pinentry_strings(pwm, 1);
 764
 765             if (error) {
 766                 pinentry_disconnect(pwm);
 767                 return error;
 768             }
 769         }
 770     }
 771
 772     error = do_getpin(pwm, result);
 773
 774     /*
 775      * Since there was input cancel any timeout setting.
 776      */
 777     alarm(0);
 778
 779     if (error) {
 780         if (error == GPG_ERR_CANCELED)
 781             return GPG_ERR_CANCELED;
 782
 783         if (pin_try != -1 && pin_try--)
 784             goto getpin_again;
 785
 786         if (pwm->pctx)
 787             pinentry_disconnect(pwm);
 788
 789         *try_n = pin_try;
 790         return error;
 791     }
 792
 793     return 0;
 794 }
 795 #endif
 796
 797 gpg_error_t pwmd_open_nb_finalize(pwm_t *pwm, pwmd_nb_status_t *pw)
 798 {
 799     gpg_error_t error;
 800
 801 #ifndef USE_PINENTRY
 802     return GPG_ERR_NOT_IMPLEMENTED;
 803 #endif
 804
 805     if (!pwm || !pw || !pw->filename[0])
 806         return GPG_ERR_INV_ARG;
 807
 808     close(pw->fd);
 809
 810     if (pw->error) {
 811         error = pw->error;
 812         goto fail;
 813     }
 814
 815     if (pwm->filename)
 816         xfree(pwm->filename);
 817
 818     pwm->filename = xstrdup(pw->filename);
 819     memset(pw, 0, sizeof(pwmd_nb_status_t));
 820     return 0;
 821
 822 fail:
 823     memset(pw, 0, sizeof(pwmd_nb_status_t));
 824     return error;
 825 }
 826
 827 static gpg_error_t do_open_command(pwm_t *pwm, const char *filename, char *password)
 828 {
 829     char buf[ASSUAN_LINELENGTH];
 830     gpg_error_t error;
 831     char *result = NULL;
 832
 833     snprintf(buf, sizeof(buf), "OPEN %s %s", filename, password ? password : "");
 834     error = send_command(pwm, &result, buf);
 835     memset(buf, 0, sizeof(buf));
 836
 837     if (error && result)
 838         xfree(result);
 839
 840     return error;
 841 }
 842
 843 static int do_pwmd_open(pwm_t *pwm, gpg_error_t *error, const char *filename,
 844         int nb, int timeout)
 845 {
 846     char *result = NULL;
 847     char *password = NULL;
 848     char path[PATH_MAX];
 849 #ifdef USE_PINENTRY
 850     int pin_try;
 851 #endif
 852
 853     if (!pwm || !filename || !*filename) {
 854         *error = GPG_ERR_INV_ARG;
 855         return nb ? -1 : 1;
 856     }
 857
 858 #ifdef USE_PINENTRY
 859     pin_try = pwm->pinentry_tries - 1;
 860 #endif
 861
 862     /*
 863      * Avoid calling pinentry if the password is cached on the server or if
 864      * this is a new file.
 865      */
 866     *error = pwmd_command(pwm, &result, "GETCONFIG data_directory");
 867
 868     if (*error)
 869         return nb ? -1 : 1;
 870
 871     snprintf(path, sizeof(path), "%s/%s", result, filename);
 872     pwmd_free_result(result);
 873
 874     if (access(path, R_OK) == -1) {
 875         if (errno == ENOENT)
 876             goto gotpassword;
 877     }
 878
 879     *error = pwmd_command(pwm, &result, "ISCACHED %s", filename);
 880
 881     if (*error == EPWMD_CACHE_NOT_FOUND) {
 882         if (pwm->passfunc) {
 883             password = pwm->passfunc(pwm, pwm->passdata);
 884             goto gotpassword;
 885         }
 886
 887 #ifdef USE_PINENTRY
 888         /*
 889          * Get the password from pinentry.
 890          */
 891         if (pwm->use_pinentry) {
 892             /*
 893              * Nonblocking is wanted. fork() then return a file descriptor
 894              * that the client can use to read() from.
 895              */
 896             if (nb) {
 897                 int p[2];
 898                 pid_t pid;
 899                 pwmd_nb_status_t pw;
 900
 901                 if (pipe(p) == -1) {
 902                     *error = gpg_error_from_syserror();
 903                     return -1;
 904                 }
 905
 906 #ifdef WITH_LIBPTH
 907                 pid = pth_fork();
 908 #else
 909                 pid = fork();
 910 #endif
 911
 912                 switch (pid) {
 913                     case 0:
 914                         close(p[0]);
 915                         strncpy(pw.filename, filename, sizeof(pw.filename));
 916                         pw.filename[sizeof(pw.filename)-1] = 0;
 917                         pw.fd = p[0];
 918
 919                         if (timeout > 0) {
 920                             gpwm = pwm;
 921                             gtimeout = timeout;
 922                             gelapsed = 0;
 923                         }
 924
 925 getpin_nb_again:
 926                         *error = getpin(pwm, &password, &pin_try, 0);
 927
 928                         if (*error) {
 929 getpin_nb_fail:
 930                             if (pwm->pctx)
 931                                 pinentry_disconnect(pwm);
 932
 933                             if (gtimeout && gelapsed >= gtimeout)
 934                                 *error = GPG_ERR_TIMEOUT;
 935
 936                             pw.error = *error;
 937 #ifdef WITH_LIBPTH
 938                             pth_write(p[1], &pw, sizeof(pw));
 939 #else
 940                             write(p[1], &pw, sizeof(pw));
 941 #endif
 942                             close(p[1]);
 943                             _exit(1);
 944                         }
 945
 946                         /*
 947                          * Don't count the time it takes to open the file
 948                          * which may have many iterations.
 949                          */
 950                         signal(SIGALRM, SIG_DFL);
 951                         *error = do_open_command(pwm, filename, password);
 952
 953                         if (timeout)
 954                             signal(SIGALRM, catchsig);
 955
 956                         if (pwm->pctx && *error == EPWMD_BADKEY) {
 957                             if (pin_try-- > 0)
 958                                 goto getpin_nb_again;
 959
 960                             goto getpin_nb_fail;
 961                         }
 962
 963                         pinentry_disconnect(pwm);
 964                         pw.error = 0;
 965 #ifdef WITH_LIBPTH
 966                         pth_write(p[1], &pw, sizeof(pw));
 967 #else
 968                         write(p[1], &pw, sizeof(pw));
 969 #endif
 970                         close(p[1]);
 971                         _exit(0);
 972                         break;
 973                     case -1:
 974                         *error = gpg_error_from_syserror();
 975                         close(p[0]);
 976                         close(p[1]);
 977                         return -1;
 978                     default:
 979                         break;
 980                 }
 981
 982                 close(p[1]);
 983                 *error = 0;
 984                 return p[0];
 985             }
 986         }
 987         else {
 988 #endif
 989             /*
 990              * Not using pinentry and the file was not found
 991              * in the cache.
 992              */
 993             password = pwm->password;
 994 #ifdef USE_PINENTRY
 995         }
 996 #endif
 997     }
 998     else if (*error)
 999         return nb ? -1 : 1;
1000
1001 gotpassword:
1002     *error = do_open_command(pwm, filename, password);
1003
1004     /*
1005      * Keep the user defined password set with pwmd_setopt(). The password may
1006      * be needed later (pwmd_save()) depending on the pwmd file cache settings.
1007      */
1008     if (password && password != pwm->password)
1009         xfree(password);
1010
1011 #ifdef USE_PINENTRY
1012     if (*error == EPWMD_BADKEY) {
1013         if (pin_try-- > 0 && !nb) {
1014             *error = pwmd_command(pwm, &result, "OPTION TITLE=%s",
1015                     N_("Invalid password, please try again."));
1016
1017             if (*error)
1018                 return 1;
1019
1020             goto gotpassword;
1021         }
1022
1023         if (nb)
1024             pinentry_disconnect(pwm);
1025
1026         return nb ? -1 : 1;
1027     }
1028 #endif
1029
1030     if (!*error) {
1031         if (pwm->filename)
1032             xfree(pwm->filename);
1033
1034         pwm->filename = xstrdup(filename);
1035     }
1036
1037     /*
1038      * The file is cached or the file is a new file.
1039      */
1040     if (nb)
1041         return *error ? -1 : -2;
1042
1043     return *error ? 1 : 0;
1044 }
1045
1046 gpg_error_t pwmd_open(pwm_t *pwm, const char *filename)
1047 {
1048     gpg_error_t error;
1049
1050     do_pwmd_open(pwm, &error, filename, 0, 0);
1051     return error;
1052 }
1053
1054 int pwmd_open_nb(pwm_t *pwm, gpg_error_t *error, const char *filename,
1055         int timeout)
1056 {
1057 #ifndef USE_PINENTRY
1058     *error = GPG_ERR_NOT_IMPLEMENTED;
1059     return -1;
1060 #else
1061     return do_pwmd_open(pwm, error, filename, 1, timeout);
1062 #endif
1063 }
1064
1065 #ifdef USE_PINENTRY
1066 static gpg_error_t do_save_getpin(pwm_t *pwm, char **password)
1067 {
1068     int confirm = 0;
1069     gpg_error_t error;
1070     char *result = NULL;
1071     int pin_try = -1;
1072
1073 again:
1074     error = getpin(pwm, &result, &pin_try, confirm ? 2 : 0);
1075
1076     if (error) {
1077         if (pwm->pctx)
1078             pinentry_disconnect(pwm);
1079
1080         if (*password)
1081             xfree(*password);
1082
1083         return error;
1084     }
1085
1086     if (!confirm++) {
1087         *password = result;
1088         goto again;
1089     }
1090
1091     if (strcmp(*password, result)) {
1092         xfree(*password);
1093         xfree(result);
1094         pinentry_disconnect(pwm);
1095         error = EPWMD_BADKEY;
1096         return error;
1097     }
1098
1099     xfree(result);
1100     pinentry_disconnect(pwm);
1101     return 0;
1102 }
1103 #endif
1104
1105 static gpg_error_t do_save_command(pwm_t *pwm, char *password)
1106 {
1107     char buf[ASSUAN_LINELENGTH];
1108     gpg_error_t error;
1109     char *result = NULL;
1110
1111     snprintf(buf, sizeof(buf), "SAVE %s", password ? password : "");
1112     error = send_command(pwm, &result, buf);
1113     memset(&buf, 0, sizeof(buf));
1114
1115     if (error && result)
1116         xfree(result);
1117
1118     return error;
1119 }
1120
1121 gpg_error_t pwmd_save_nb_finalize(pwm_t *pwm, pwmd_nb_status_t *pw)
1122 {
1123     gpg_error_t rc;
1124
1125 #ifndef USE_PINENTRY
1126     return GPG_ERR_NOT_IMPLEMENTED;
1127 #endif
1128
1129     if (!pwm || !pw || !pw->filename[0])
1130         return GPG_ERR_INV_ARG;
1131
1132     close(pw->fd);
1133     rc = pw->error;
1134     memset(pw, 0, sizeof(pwmd_nb_status_t));
1135     return rc;
1136 }
1137
1138 static int do_pwmd_save(pwm_t *pwm, gpg_error_t *error, int nb)
1139 {
1140     char *result = NULL;
1141     char *password = NULL;
1142
1143     if (!pwm) {
1144         *error = GPG_ERR_INV_ARG;
1145         return nb ? -1 : 1;
1146     }
1147
1148     if (pwm->use_pinentry || pwm->passfunc) {
1149         *error = pwmd_command(pwm, &result, "ISCACHED %s", pwm->filename);
1150
1151         if (*error == EPWMD_CACHE_NOT_FOUND) {
1152 #ifdef USE_PINENTRY
1153             if (pwm->use_pinentry) {
1154                 if (nb) {
1155                     int p[2];
1156                     pid_t pid;
1157                     pwmd_nb_status_t pw;
1158
1159                     if (pipe(p) == -1) {
1160                         *error = gpg_error_from_syserror();
1161                         return -1;
1162                     }
1163
1164 #ifdef WITH_LIBPTH
1165                     pid = pth_fork();
1166 #else
1167                     pid = fork();
1168 #endif
1169
1170                     switch (pid) {
1171                         case 0:
1172                             close(p[0]);
1173                             strncpy(pw.filename, pwm->filename, sizeof(pw.filename));
1174                             pw.filename[sizeof(pw.filename)-1] = 0;
1175                             pw.fd = p[0];
1176
1177                             do {
1178                                 password = NULL;
1179                                 *error = do_save_getpin(pwm, &password);
1180                             } while (*error == EPWMD_BADKEY);
1181
1182                             if (*error) {
1183                                 if (pwm->pctx)
1184                                     pinentry_disconnect(pwm);
1185
1186                                 pw.error = *error;
1187 #ifdef WITH_LIBPTH
1188                                 pth_write(p[1], &pw, sizeof(pw));
1189 #else
1190                                 write(p[1], &pw, sizeof(pw));
1191 #endif
1192                                 close(p[1]);
1193                                 _exit(1);
1194                             }
1195
1196                             *error = do_save_command(pwm, password);
1197                             pinentry_disconnect(pwm);
1198                             pw.error = *error;
1199 #ifdef WITH_LIBPTH
1200                             pth_write(p[1], &pw, sizeof(pw));
1201 #else
1202                             write(p[1], &pw, sizeof(pw));
1203 #endif
1204                             close(p[1]);
1205                             _exit(0);
1206                             break;
1207                         case -1:
1208                             *error = gpg_error_from_syserror();
1209                             close(p[0]);
1210                             close(p[1]);
1211                             return -1;
1212                         default:
1213                             break;
1214                     }
1215
1216                     close(p[1]);
1217                     *error = 0;
1218                     return p[0];
1219                 }
1220
1221                 *error = do_save_getpin(pwm, &password);
1222
1223                 if (*error)
1224                     return 1;
1225             }
1226             else {
1227 #endif
1228                 if (pwm->passfunc)
1229                     password = (*pwm->passfunc)(pwm, pwm->passdata);
1230 #ifdef USE_PINENTRY
1231             }
1232 #endif
1233         }
1234         else {
1235             if (*error)
1236                 return nb ? -1 : 1;
1237         }
1238     }
1239     else
1240         password = pwm->password;
1241
1242     *error = do_save_command(pwm, password);
1243
1244     if (password && password != pwm->password)
1245         xfree(password);
1246
1247     if (nb)
1248         return *error ? -1 : -2;
1249
1250     return *error ? 1 : 0;
1251 }
1252
1253 int pwmd_save_nb(pwm_t *pwm, gpg_error_t *error)
1254 {
1255 #ifndef USE_PINENTRY
1256     *error = GPG_ERR_NOT_IMPLEMENTED;
1257     return -1;
1258 #else
1259     return do_pwmd_save(pwm, error, 1);
1260 #endif
1261 }
1262
1263 gpg_error_t pwmd_save(pwm_t *pwm)
1264 {
1265     gpg_error_t error;
1266
1267     do_pwmd_save(pwm, &error, 0);
1268     return error;
1269 }
1270
1271 gpg_error_t pwmd_setopt(pwm_t *pwm, pwmd_option_t opt, ...)
1272 {
1273     va_list ap;
1274 #ifdef USE_PINENTRY
1275     int n = va_arg(ap, int);
1276     char *result;
1277 #endif
1278     char *arg1;
1279     gpg_error_t error = 0;
1280
1281     if (!pwm)
1282         return GPG_ERR_INV_ARG;
1283
1284     va_start(ap, opt);
1285
1286     switch (opt) {
1287         case PWMD_OPTION_STATUS_FUNC:
1288             pwm->status_func = va_arg(ap, pwmd_status_fn);
1289             break;
1290         case PWMD_OPTION_STATUS_DATA:
1291             pwm->status_data = va_arg(ap, void *);
1292             break;
1293         case PWMD_OPTION_PASSWORD_FUNC:
1294             pwm->passfunc = va_arg(ap, pwmd_password_fn);
1295             break;
1296         case PWMD_OPTION_PASSWORD_DATA:
1297             pwm->passdata = va_arg(ap, void *);
1298             break;
1299         case PWMD_OPTION_PASSWORD:
1300             arg1 = va_arg(ap, char *);
1301
1302             if (pwm->password)
1303                 xfree(pwm->password);
1304
1305             pwm->password = xstrdup(arg1);
1306             break;
1307 #ifdef USE_PINENTRY
1308         case PWMD_OPTION_PINENTRY:
1309             n = va_arg(ap, int);
1310
1311             if (n != 0 && n != 1) {
1312                 va_end(ap);
1313                 error = GPG_ERR_INV_VALUE;
1314             }
1315             else {
1316                 pwm->use_pinentry = n;
1317                 error = pwmd_command(pwm, &result, "OPTION PINENTRY=%i",
1318                         !pwm->use_pinentry);
1319             }
1320             break;
1321         case PWMD_OPTION_PINENTRY_TRIES:
1322             n = va_arg(ap, int);
1323
1324             if (n <= 0) {
1325                 va_end(ap);
1326                 error = GPG_ERR_INV_VALUE;
1327             }
1328             else
1329                 pwm->pinentry_tries = n;
1330             break;
1331         case PWMD_OPTION_PINENTRY_PATH:
1332             if (pwm->pinentry_path)
1333                 xfree(pwm->pinentry_path);
1334
1335             pwm->pinentry_path = xstrdup(va_arg(ap, char *));
1336             break;
1337         case PWMD_OPTION_PINENTRY_TTY:
1338             if (pwm->pinentry_tty)
1339                 xfree(pwm->pinentry_tty);
1340
1341             pwm->pinentry_tty = xstrdup(va_arg(ap, char *));
1342             break;
1343         case PWMD_OPTION_PINENTRY_DISPLAY:
1344             if (pwm->pinentry_display)
1345                 xfree(pwm->pinentry_display);
1346
1347             pwm->pinentry_display = xstrdup(va_arg(ap, char *));
1348             break;
1349         case PWMD_OPTION_PINENTRY_TERM:
1350             if (pwm->pinentry_term)
1351                 xfree(pwm->pinentry_term);
1352
1353             pwm->pinentry_term = xstrdup(va_arg(ap, char *));
1354             break;
1355         case PWMD_OPTION_PINENTRY_TITLE:
1356             if (pwm->title)
1357                 xfree(pwm->title);
1358             pwm->title = percent_escape(va_arg(ap, char *));
1359             break;
1360         case PWMD_OPTION_PINENTRY_PROMPT:
1361             if (pwm->prompt)
1362                 xfree(pwm->prompt);
1363             pwm->prompt = percent_escape(va_arg(ap, char *));
1364             break;
1365         case PWMD_OPTION_PINENTRY_DESC:
1366             if (pwm->desc)
1367                 xfree(pwm->desc);
1368             pwm->desc = percent_escape(va_arg(ap, char *));
1369             break;
1370 #else
1371         case PWMD_OPTION_PINENTRY:
1372         case PWMD_OPTION_PINENTRY_TRIES:
1373         case PWMD_OPTION_PINENTRY_PATH:
1374         case PWMD_OPTION_PINENTRY_TTY:
1375         case PWMD_OPTION_PINENTRY_DISPLAY:
1376         case PWMD_OPTION_PINENTRY_TERM:
1377         case PWMD_OPTION_PINENTRY_TITLE:
1378         case PWMD_OPTION_PINENTRY_PROMPT:
1379         case PWMD_OPTION_PINENTRY_DESC:
1380             error = GPG_ERR_NOT_IMPLEMENTED;
1381             break;
1382 #endif
1383         default:
1384             error = GPG_ERR_NOT_IMPLEMENTED;
1385             break;
1386     }
1387
1388     va_end(ap);
1389     return error;
1390 }
1391
1392 gpg_error_t pwmd_assuan_ctx(pwm_t *pwm, assuan_context_t *ctx, int *fd)
1393 {
1394     if (!pwm)
1395         return GPG_ERR_INV_ARG;
1396
1397     *ctx = pwm->ctx;
1398     *fd = pwm->fd;
1399     return 0;
1400 }