src/util-misc.c

   1 /*
   2     Copyright (C) 2006-2018 Ben Kibbey <bjk@luxsci.net>
   3
   4     This file is part of pwmd.
   5
   6     Pwmd 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 2 of the License, or
   9     (at your option) any later version.
  10
  11     Pwmd 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 Pwmd.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19 #ifdef HAVE_CONFIG_H
  20 #include <config.h>
  21 #endif
  22
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <errno.h>
  26 #include <unistd.h>
  27 #include <sys/types.h>
  28 #include <sys/stat.h>
  29 #include <fcntl.h>
  30 #include <string.h>
  31 #include <ctype.h>
  32 #include <pwd.h>
  33
  34 #include "pwmd-error.h"
  35 #include <gcrypt.h>
  36 #include "util-misc.h"
  37 #include "util-string.h"
  38 #include "mutex.h"
  39 #include "cache.h"
  40 #include "mem.h"
  41
  42 void log_write (const char *fmt, ...);
  43
  44 int
  45 valid_filename (const char *filename)
  46 {
  47   const char *p;
  48
  49   if (!filename || !*filename)
  50     return 0;
  51
  52   if (filename[0] == '-' && filename[1] == 0)
  53     return 0;
  54
  55   for (p = filename; *p; p++)
  56     {
  57       if (*p == '/' || isspace (*p))
  58         return 0;
  59     }
  60
  61   return 1;
  62 }
  63
  64 /* If 'user' is null then lookup entry for 'uid'. Caller must free 'buf'. */
  65 struct passwd *
  66 get_pwd_struct (const char *user, uid_t uid, struct passwd *pw, char **buf,
  67                 gpg_error_t *rc)
  68 {
  69   struct passwd *result = NULL;
  70 #ifdef HAVE_GETPWNAM_R
  71   size_t len;
  72   int err = 0;
  73
  74   len = sysconf (_SC_GETPW_R_SIZE_MAX);
  75   if (len == -1)
  76     len = 16384;
  77
  78   *buf = xmalloc (len);
  79   if (!*buf)
  80     return NULL;
  81
  82   if (user)
  83     err = getpwnam_r (user, pw, *buf, len, &result);
  84   else
  85     err = getpwuid_r (uid, pw, *buf, len, &result);
  86
  87   if (!err && result)
  88     return result;
  89
  90   xfree (*buf);
  91   *buf = NULL;
  92   errno = err;
  93   *rc = gpg_error_from_errno (err);
  94   return NULL;
  95 #else
  96   if (buf)
  97     *buf = NULL;
  98
  99   errno = 0;
 100   if (user)
 101     result = getpwnam (user);
 102   else
 103     result = getpwuid (uid);
 104
 105   if (!result)
 106     *rc = gpg_error_from_syserror ();
 107
 108   return result;
 109 #endif
 110 }
 111
 112 static char *
 113 get_pwd_entry(uid_t uid, int which)
 114 {
 115   gpg_error_t rc;
 116   char *buf;
 117   struct passwd pw;
 118   struct passwd *result = get_pwd_struct (NULL, uid, &pw, &buf, &rc);
 119   char *value = NULL;
 120
 121   if (!result)
 122     return NULL;
 123
 124   if (result)
 125     {
 126       if (!which)
 127         value = str_dup (result->pw_dir);
 128       else
 129         value = str_dup (result->pw_name);
 130     }
 131
 132   xfree (buf);
 133   return value;
 134 }
 135
 136 char *
 137 get_username (uid_t uid)
 138 {
 139   return get_pwd_entry (uid, 1);
 140 }
 141
 142 char *
 143 get_home_dir ()
 144 {
 145   if (home_directory)
 146     return home_directory;
 147
 148   home_directory = get_pwd_entry (getuid(), 0);
 149   return home_directory;
 150 }
 151
 152 char *
 153 expand_homedir (char *str)
 154 {
 155   char *p = str;
 156
 157   if (*p++ == '~')
 158     {
 159       char *dir = get_pwd_entry(getuid(), 0);
 160       char *s;
 161
 162       if (!dir)
 163         return NULL;
 164
 165       s = str_asprintf ("%s%s", dir, p);
 166       xfree (dir);
 167       return s;
 168     }
 169
 170   return str_dup (str);
 171 }
 172
 173 /* The 'more' parameter lets the calling command process remaining
 174  * non-option arguments. */
 175 gpg_error_t
 176 parse_options (char **line, struct argv_s * args[], void *data, int more)
 177 {
 178   char *p = *line;
 179   gpg_error_t rc = 0;
 180
 181   for (; p && *p; p++)
 182     {
 183       while (*p == ' ')
 184         p++;
 185
 186       if (!*p)
 187         break;
 188
 189       if (*p == '-' && *(p + 1) == '-')
 190         {
 191           p += 2;
 192           char opt[255] = { 0 }, value[255] =
 193           {
 194           0};
 195           char *tp;
 196           unsigned len;
 197
 198           if (!*p || *p == ' ')
 199             {
 200               if (*p)
 201                 p++;
 202
 203               break;
 204             }
 205
 206           for (tp = opt, len = 0; *p; p++, len++)
 207             {
 208               if (len + 1 == 255)
 209                 return GPG_ERR_LINE_TOO_LONG;
 210
 211               if (*p == ' ' || *p == '=')
 212                 {
 213                   *tp = 0;
 214
 215                   if (*p == '=')
 216                     {
 217                       int inquote = 0;
 218
 219                       p++;
 220
 221                       for (tp = value, len = 0; *p; p++, len++)
 222                         {
 223                           if (len + 1 == 255)
 224                             return GPG_ERR_LINE_TOO_LONG;
 225
 226                           if (*p == '\"')
 227                             {
 228                               inquote = !inquote;
 229                               continue;
 230                             }
 231                           else if (*p == ' ' && !inquote)
 232                             break;
 233
 234                           *tp++ = *p;
 235                         }
 236
 237                       *tp = 0;
 238                     }
 239
 240                   break;
 241                 }
 242
 243               *tp++ = *p;
 244             }
 245
 246           *tp = 0;
 247           int match = 0;
 248
 249           for (int i = 0; args[i]; i++)
 250             {
 251               if (!strcmp (args[i]->opt, opt))
 252                 {
 253                   log_write2 ("param: name='%s' value='%s'", opt, value);
 254                   if (args[i]->type == OPTION_TYPE_NOARG && *value)
 255                     return GPG_ERR_SYNTAX;
 256                   else if (args[i]->type == OPTION_TYPE_ARG && !*value)
 257                     return GPG_ERR_SYNTAX;
 258
 259                   if (args[i]->func)
 260                     {
 261                       rc = args[i]->func (data, value);
 262                       if (rc)
 263                         return rc;
 264                     }
 265
 266                   match = 1;
 267                   break;
 268                 }
 269             }
 270
 271           if (!match)
 272             return GPG_ERR_UNKNOWN_OPTION;
 273
 274           if (!*p)
 275             break;
 276
 277           continue;
 278         }
 279
 280       if (*(p+1) && !more)
 281         return GPG_ERR_SYNTAX;
 282
 283       break;
 284     }
 285
 286   *line = p;
 287   return rc;
 288 }
 289
 290 char *
 291 bin2hex (const unsigned char *data, size_t len)
 292 {
 293   size_t size = len * 2 + 1;
 294   char buf[size];
 295   size_t n;
 296
 297   buf[0] = 0;
 298
 299   for (n = 0; n < len; n++)
 300     {
 301       char c[3];
 302
 303       sprintf (c, "%02X", data[n]);
 304       strcat (buf, c);
 305     }
 306
 307   return str_dup (buf);
 308 }
 309
 310 static char *
 311 html_escape (const char *line, size_t len, int space)
 312 {
 313   struct string_s *string = string_new ("");
 314   size_t n;
 315   char *tmp;
 316
 317   if (!string)
 318     return NULL;
 319
 320   for (n = 0; n < len; n++)
 321     {
 322       switch (line[n])
 323         {
 324         case '<':
 325           string = string_append (string, "&lt;");
 326           break;
 327         case '>':
 328           string = string_append (string, "&gt;");
 329           break;
 330         case ' ':
 331           if (space)
 332             {
 333               string = string_append (string, "%20");
 334               break;
 335             }
 336         default:
 337           string = string_append_printf (string, "%c", line[n]);
 338           break;
 339         }
 340     }
 341
 342   tmp = string->str;
 343   string_free (string, 0);
 344   return tmp;
 345 }
 346
 347 static char *
 348 strip_texi_html (const char *line)
 349 {
 350   size_t len;
 351   const char *p;
 352   char *tmp;
 353   struct string_s *string = string_new ("<html><body>");
 354
 355   if (!string)
 356     return NULL;
 357
 358   /* The command usage text. */
 359   p = strchr (line, '\n');
 360   if (p)
 361     {
 362       len = strlen (line)-strlen(p);
 363       tmp = html_escape (line, len, 0);
 364       string = string_append_printf (string, "<b>%s</b><p>", tmp);
 365       xfree (tmp);
 366       p++;
 367     }
 368   else
 369     p = line;
 370
 371   for (; p && *p; p++)
 372     {
 373       int non_anchor = 1;
 374       int var = 0;
 375       int code = 0;
 376       int emph = 0;
 377       int cite = 0;
 378
 379       if (*p == '@' && *(p + 1) != '@')
 380         {
 381           p++;
 382
 383           if (!strncasecmp (p, "end ", 4))
 384             {
 385               p += 4;
 386               if (!strncasecmp (p, "table", 5))
 387                 {
 388                   string = string_append (string, "</p>");
 389                 }
 390               else if (!strncasecmp (p, "example", 7))
 391                 {
 392                   string = string_append (string, "</code>");
 393                 }
 394
 395               while (*p++ != '\n');
 396               p--;
 397               continue;
 398             }
 399           else if (!strncasecmp (p, "table ", 6))
 400             {
 401               while (*p++ != '\n');
 402               p--;
 403               continue;
 404             }
 405           else if (!strncasecmp (p, "example", 7))
 406             {
 407               string = string_append (string, "<code>");
 408               while (*p++ != '\n');
 409               p--;
 410               continue;
 411             }
 412           else if (!strncasecmp (p, "sp ", 3))
 413             {
 414               while (*p++ != '\n');
 415               p--;
 416               string = string_append (string, "<p>");
 417               continue;
 418             }
 419           else if (!strncasecmp (p, "item ", 5))
 420             {
 421               p += 5;
 422               string = string_append (string, "<p><b>");
 423               tmp = strchr (p, '\n');
 424               len = strlen (p) - strlen (tmp);
 425               while (len--)
 426                 {
 427                   if (*p == '<')
 428                     {
 429                       string = string_append (string, "&lt;");
 430                       p++;
 431                     }
 432                   else if (*p == '>')
 433                     {
 434                       string = string_append (string, "&gt;");
 435                       p++;
 436                     }
 437                   else
 438                     string = string_append_printf (string, "%c", *p++);
 439                 }
 440
 441               string = string_append (string, "</b><br/>");
 442               continue;
 443             }
 444           else if (!strncasecmp (p, "pxref", 5)
 445                    || !strncasecmp (p, "npxref", 6))
 446             {
 447               int n = 0;
 448
 449               if (!strncasecmp (p, "npxref", 6))
 450                 n++;
 451
 452               p += n ? 7 : 6;
 453               non_anchor = 0;
 454               string = string_append_printf (string, "%s<a href=\"",
 455                                              n ? "" : "see ");
 456               goto close;
 457             }
 458           else if (!strncasecmp (p, "xref", 4))
 459             {
 460               p += 5;
 461               non_anchor = 0;
 462               string = string_append (string, "See <a href=\"");
 463               goto close;
 464             }
 465           else if (!strncasecmp (p, "url", 3))
 466             {
 467               p += 4;
 468               non_anchor = 0;
 469               string = string_append (string, "<a href=\"");
 470               goto close;
 471             }
 472           else if (!strncasecmp (p, "key", 3))
 473             {
 474               p += 4;
 475               goto close;
 476             }
 477           else if (!strncasecmp (p, "file", 4))
 478             {
 479               p += 5;
 480               var = 1;
 481               string = string_append (string, "<var>");
 482               goto close;
 483             }
 484           else if (!strncasecmp (p, "var", 3))
 485             {
 486               p += 4;
 487               var = 1;
 488               string = string_append (string, "<var>");
 489               goto close;
 490             }
 491           else if (!strncasecmp (p, "option", 6))
 492             {
 493               p += 7;
 494               var = 1;
 495               string = string_append (string, "<var>");
 496               goto close;
 497             }
 498           else if (!strncasecmp (p, "code", 4))
 499             {
 500               p += 5;
 501               code = 1;
 502               string = string_append (string, "<b>");
 503               goto close;
 504             }
 505           else if (!strncasecmp (p, "emph", 4))
 506             {
 507               p += 5;
 508               emph = 1;
 509               string = string_append (string, "<em>");
 510               goto close;
 511             }
 512           else if (!strncasecmp (p, "command", 7))
 513             {
 514               p += 8;
 515               emph = 1;
 516               string = string_append (string, "<em>");
 517               goto close;
 518             }
 519           else if (!strncasecmp (p, "cite", 4))
 520             {
 521               p += 5;
 522               cite = 1;
 523               string = string_append (string, "<cite>");
 524               goto close;
 525             }
 526           else if (!strncasecmp (p, "abbr", 4))
 527             {
 528               p += 5;
 529               emph = 1;
 530               string = string_append (string, "<em>");
 531               goto close;
 532             }
 533           else if (!strncasecmp (p, "*", 1))
 534             {
 535               string = string_append (string, "<br/>");
 536               continue;
 537             }
 538
 539           while (*p && *p != '{')
 540             {
 541               if (*++p == '*')
 542                 {
 543                   p++;
 544                   goto append;
 545                 }
 546             }
 547
 548         close:
 549           if (*p)
 550             {
 551               char buf [255];
 552
 553               tmp = strchr (p, '}');
 554               len = strlen (p) - strlen (tmp);
 555               tmp = buf;
 556               while (len--)
 557                 *tmp++ = *p++;
 558
 559               *tmp = 0;
 560
 561               if (*p)
 562                 p++;
 563
 564               if (!non_anchor)
 565                 {
 566                   tmp = html_escape (buf, strlen (buf), 1);
 567                   string = string_append_printf (string, "%s\">%s</a>", tmp, buf);
 568                   xfree (tmp);
 569                 }
 570               else
 571                 string = string_append (string, buf);
 572
 573               if (var)
 574                 string = string_append (string, "</var>");
 575               else if (code)
 576                 string = string_append (string, "</b>");
 577               else if (emph)
 578                 string = string_append (string, "</em>");
 579               else if (cite)
 580                 string = string_append (string, "</cite>");
 581             }
 582         }
 583       else if (*p == '@' && *(p + 1) == '@')
 584         p++;
 585
 586     append:
 587       string = string_append_printf (string, "%c", *p);
 588
 589       if (!*p)
 590         break;
 591     }
 592
 593   string = string_append (string, "</body></html>");
 594   tmp = string->str;
 595   string_free (string, 0);
 596   return tmp;
 597 }
 598
 599 static char *
 600 strip_texi (const char *str, int html)
 601 {
 602   const char *p;
 603   char *s;
 604   int c = 0;
 605
 606   if (html)
 607     return strip_texi_html (str);
 608
 609   s = str_dup (str);
 610   if (!s)
 611     return NULL;
 612
 613   for (p = str; *p; p++)
 614     {
 615       if (*p == '@' && *(p + 1) != '@')
 616         {
 617           p++;
 618
 619           if (!strncasecmp (p, "table", 5)
 620               || !strncasecmp (p, "end ", 4))
 621             {
 622               while (*p++ != '\n');
 623               p--;
 624               continue;
 625             }
 626           else if (!strncasecmp (p, "example", 7)
 627                    || !strncasecmp (p, "end ", 4))
 628             {
 629               while (*p++ != '\n');
 630               p--;
 631               continue;
 632             }
 633           else if (!strncasecmp (p, "sp ", 3))
 634             {
 635               while (*p++ != '\n');
 636               p--;
 637               continue;
 638             }
 639           else if (!strncasecmp (p, "item", 4))
 640             {
 641               p += 5;
 642               while (*p && *p != '\n')
 643                 s[c++] = *p++;
 644
 645               s[c++] = '\n';
 646               continue;
 647             }
 648           else if (!strncasecmp (p, "pxref", 5))
 649             {
 650               p += 5;
 651               strcat (s, "see ");
 652               c = strlen (s);
 653               goto close;
 654             }
 655           else if (!strncasecmp (p, "xref", 4))
 656             {
 657               p += 4;
 658               strcat (s, "See ");
 659               c = strlen (s);
 660               goto close;
 661             }
 662           else if (!strncasecmp (p, "*", 1))
 663             {
 664               s[c++] = '\n';
 665               s[c] = 0;
 666               continue;
 667             }
 668
 669           while (*p && *p != '{')
 670             {
 671               if (*++p == '*')
 672                 {
 673                   p++;
 674                   goto append;
 675                 }
 676             }
 677
 678         close:
 679           if (*p)
 680             {
 681               p++;
 682               s[c++] = '`';
 683               while (*p && *p != '}')
 684                 s[c++] = *p++;
 685
 686               if (*p)
 687                 p++;
 688
 689               s[c++] = '\'';
 690               s[c] = 0;
 691             }
 692         }
 693       else if (*p == '@' && *(p + 1) == '@')
 694         p++;
 695
 696     append:
 697       if (*p)
 698         s[c++] = *p;
 699
 700       s[c] = 0;
 701     }
 702
 703   s[c] = 0;
 704   return s;
 705 }
 706
 707
 708 char *
 709 strip_texi_and_wrap (const char *str, int html)
 710 {
 711   char *tmp = strip_texi (str, html);
 712   char *help = xcalloc (1, strlen (tmp) * 2 + 1);
 713   char *p, *ph;
 714   int i;
 715
 716   for (p = tmp, ph = help, i = 0; *p; p++, i++)
 717     {
 718       if (i == 78 || *p == '\n')
 719         {
 720           if (!isspace (*p))
 721             {
 722               char *t = ph;
 723               int n = 0;
 724
 725               while (*(--t) != ' ')
 726                 n++;
 727
 728               *t++ = '\n';
 729               i = -1;
 730               p -= n;
 731               while (n--)
 732                 {
 733                   *t++ = *p++;
 734                   i++;
 735                 }
 736             }
 737           else
 738             {
 739               *ph++ = '\n';
 740               i = -1;
 741               while (*p != '\n' && *p == ' ')
 742                 p++;
 743             }
 744         }
 745
 746       if (*p == '\n')
 747         continue;
 748       *ph++ = *p;
 749     }
 750
 751   *ph = 0;
 752   xfree (tmp);
 753   return help;
 754 }
 755
 756 void
 757 free_key (void *data)
 758 {
 759   xfree (data);
 760 }
 761
 762 gpg_error_t
 763 create_thread (void *(*cb) (void *), void *data,
 764                pthread_t * tid, int detached)
 765 {
 766   pthread_attr_t attr;
 767   int n;
 768
 769   pthread_attr_init (&attr);
 770
 771   if (detached)
 772     pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
 773
 774   n = pthread_create (tid, &attr, cb, data);
 775   pthread_attr_destroy (&attr);
 776   return gpg_error_from_errno (n);
 777 }
 778
 779 void
 780 release_mutex_cb (void *arg)
 781 {
 782   pthread_mutex_t *m = (pthread_mutex_t *) arg;
 783
 784   MUTEX_UNLOCK (m);
 785 }
 786
 787 void
 788 close_fd_cb (void *arg)
 789 {
 790   int fd = *(int *)arg;
 791
 792   if (fd != -1)
 793     close (fd);
 794 }
 795
 796 gpg_error_t
 797 get_checksum_memory (void *data, size_t size, unsigned char **r_crc,
 798                      size_t *r_crclen)
 799 {
 800   size_t len = gcry_md_get_algo_dlen (GCRY_MD_CRC32);
 801   unsigned char *crc = xmalloc (len);
 802
 803   *r_crc = NULL;
 804   *r_crclen = 0;
 805
 806   if (!crc)
 807     return GPG_ERR_ENOMEM;
 808
 809   gcry_md_hash_buffer (GCRY_MD_CRC32, crc, data, size);
 810   *r_crc = crc;
 811   *r_crclen = len;
 812   return 0;
 813 }
 814
 815 /* The advisory lock should be obtained before calling this function. */
 816 gpg_error_t
 817 get_checksum (const char *filename, unsigned char **r_crc, size_t * r_crclen)
 818 {
 819   int fd = -1;
 820   unsigned char *buf;
 821   gpg_error_t rc;
 822   struct stat st;
 823
 824   rc = open_check_file (filename, &fd, &st, 1);
 825   if (rc)
 826     return rc;
 827
 828   pthread_cleanup_push (close_fd_cb, &fd);
 829   buf = xmalloc (st.st_size);
 830   if (buf)
 831     {
 832       pthread_cleanup_push (xfree, buf);
 833
 834       size_t len = read (fd, buf, st.st_size);
 835       if (len == st.st_size)
 836         {
 837           if (buf)
 838             rc = get_checksum_memory (buf, st.st_size, r_crc, r_crclen);
 839           else
 840             rc = GPG_ERR_ENOMEM;
 841         }
 842       else
 843         rc = GPG_ERR_TOO_SHORT;
 844
 845       pthread_cleanup_pop (1);
 846     }
 847   else
 848     rc = GPG_ERR_ENOMEM;
 849
 850   pthread_cleanup_pop (1);
 851   return rc;
 852 }
 853
 854 wchar_t *str_to_wchar (const char *str)
 855 {
 856     wchar_t *wc;
 857     mbstate_t ps;
 858     const char *p = str;
 859     size_t len;
 860
 861     memset (&ps, 0, sizeof(mbstate_t));
 862     len = mbsrtowcs (NULL, &p, 0, &ps);
 863     if (len == -1)
 864       return NULL;
 865
 866     wc = xcalloc (len+1, sizeof(wchar_t));
 867     if (!wc)
 868       return NULL;
 869
 870     p = str;
 871     memset (&ps, 0, sizeof(mbstate_t));
 872     len = mbsrtowcs (wc, &p, len, &ps);
 873     if (len == -1)
 874       {
 875         xfree (wc);
 876         return NULL;
 877       }
 878
 879     return wc;
 880 }
 881
 882 char *
 883 gnupg_escape (const char *str)
 884 {
 885   if (!str || !*str)
 886     return NULL;
 887
 888   char *buf = xmalloc (strlen(str)*4+1), *b = buf;
 889   const char *p;
 890
 891   if (!buf)
 892     return NULL;
 893
 894   for (p = str; p && *p; p++)
 895     {
 896       if (*p == ':')
 897         {
 898           *b++ = '\\';
 899           *b++ = 'x';
 900           *b++ = '3';
 901           *b++ = 'a';
 902           continue;
 903         }
 904       else if (*p == '\\')
 905         {
 906           *b++ = '\\';
 907           *b++ = 'x';
 908           *b++ = '5';
 909           *b++ = 'c';
 910           continue;
 911         }
 912
 913       *b++ = *p;
 914     }
 915
 916   *b = 0;
 917   return buf;
 918 }
 919
 920 /* From Beej's Guide to Network Programming. It's a good tutorial. */
 921 void *
 922 get_in_addr (struct sockaddr *sa)
 923 {
 924   if (sa->sa_family == AF_INET)
 925     return &(((struct sockaddr_in *) sa)->sin_addr);
 926
 927   return &(((struct sockaddr_in6 *) sa)->sin6_addr);
 928 }
 929
 930 gpg_error_t
 931 open_check_file (const char *filename, int *r_fd, struct stat *r_st, int reg)
 932 {
 933   int fd;
 934   gpg_error_t rc = 0;
 935
 936   if (reg)
 937     {
 938       struct stat st;
 939
 940       if (lstat (filename, &st) == -1)
 941         return gpg_err_code (gpg_error_from_syserror ());
 942
 943       if (!S_ISREG (st.st_mode))
 944         return GPG_ERR_ENODEV;
 945
 946       if (r_st)
 947         memcpy (r_st, &st, sizeof (struct stat));
 948     }
 949
 950   if (r_fd)
 951     {
 952       fd = open (filename, O_RDONLY);
 953       if (fd == -1)
 954         return gpg_err_code (gpg_error_from_syserror ());
 955
 956       if (r_st && fstat (fd, r_st) == -1)
 957         {
 958           rc = gpg_err_code (gpg_error_from_syserror ());
 959           close (fd);
 960           return rc;
 961         }
 962
 963       *r_fd = fd;
 964     }
 965
 966   return 0;
 967 }