src/gpt-auto-generator/gpt-auto-generator.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   This file is part of systemd.
   4
   5   Copyright 2013 Lennart Poettering
   6 ***/
   7
   8 #include <blkid.h>
   9 #include <stdlib.h>
  10 #include <sys/statfs.h>
  11 #include <unistd.h>
  12
  13 #include "libudev.h"
  14 #include "sd-id128.h"
  15
  16 #include "alloc-util.h"
  17 #include "blkid-util.h"
  18 #include "blockdev-util.h"
  19 #include "btrfs-util.h"
  20 #include "dirent-util.h"
  21 #include "dissect-image.h"
  22 #include "efivars.h"
  23 #include "fd-util.h"
  24 #include "fileio.h"
  25 #include "fstab-util.h"
  26 #include "generator.h"
  27 #include "gpt.h"
  28 #include "missing.h"
  29 #include "mkdir.h"
  30 #include "mount-util.h"
  31 #include "parse-util.h"
  32 #include "path-util.h"
  33 #include "proc-cmdline.h"
  34 #include "special.h"
  35 #include "specifier.h"
  36 #include "stat-util.h"
  37 #include "string-util.h"
  38 #include "udev-util.h"
  39 #include "unit-name.h"
  40 #include "util.h"
  41 #include "virt.h"
  42
  43 static const char *arg_dest = "/tmp";
  44 static bool arg_enabled = true;
  45 static bool arg_root_enabled = true;
  46 static bool arg_root_rw = false;
  47
  48 static int add_cryptsetup(const char *id, const char *what, bool rw, bool require, char **device) {
  49         _cleanup_free_ char *e = NULL, *n = NULL, *p = NULL, *d = NULL, *id_escaped = NULL, *what_escaped = NULL;
  50         _cleanup_fclose_ FILE *f = NULL;
  51         char *ret;
  52         int r;
  53
  54         assert(id);
  55         assert(what);
  56
  57         r = unit_name_from_path(what, ".device", &d);
  58         if (r < 0)
  59                 return log_error_errno(r, "Failed to generate unit name: %m");
  60
  61         e = unit_name_escape(id);
  62         if (!e)
  63                 return log_oom();
  64
  65         r = unit_name_build("systemd-cryptsetup", e, ".service", &n);
  66         if (r < 0)
  67                 return log_error_errno(r, "Failed to generate unit name: %m");
  68
  69         id_escaped = specifier_escape(id);
  70         if (!id_escaped)
  71                 return log_oom();
  72
  73         what_escaped = specifier_escape(what);
  74         if (!what_escaped)
  75                 return log_oom();
  76
  77         p = strjoin(arg_dest, "/", n);
  78         if (!p)
  79                 return log_oom();
  80
  81         f = fopen(p, "wxe");
  82         if (!f)
  83                 return log_error_errno(errno, "Failed to create unit file %s: %m", p);
  84
  85         fprintf(f,
  86                 "# Automatically generated by systemd-gpt-auto-generator\n\n"
  87                 "[Unit]\n"
  88                 "Description=Cryptography Setup for %%I\n"
  89                 "Documentation=man:systemd-gpt-auto-generator(8) man:systemd-cryptsetup@.service(8)\n"
  90                 "DefaultDependencies=no\n"
  91                 "Conflicts=umount.target\n"
  92                 "BindsTo=dev-mapper-%%i.device %s\n"
  93                 "Before=umount.target cryptsetup.target\n"
  94                 "After=%s\n"
  95                 "IgnoreOnIsolate=true\n"
  96                 "[Service]\n"
  97                 "Type=oneshot\n"
  98                 "RemainAfterExit=yes\n"
  99                 "TimeoutSec=0\n" /* the binary handles timeouts anyway */
 100                 "KeyringMode=shared\n" /* make sure we can share cached keys among instances */
 101                 "ExecStart=" SYSTEMD_CRYPTSETUP_PATH " attach '%s' '%s' '' '%s'\n"
 102                 "ExecStop=" SYSTEMD_CRYPTSETUP_PATH " detach '%s'\n",
 103                 d, d,
 104                 id_escaped, what_escaped, rw ? "" : "read-only",
 105                 id_escaped);
 106
 107         r = fflush_and_check(f);
 108         if (r < 0)
 109                 return log_error_errno(r, "Failed to write file %s: %m", p);
 110
 111         r = generator_add_symlink(arg_dest, d, "wants", n);
 112         if (r < 0)
 113                 return r;
 114
 115         if (require) {
 116                 const char *dmname;
 117
 118                 r = generator_add_symlink(arg_dest, "cryptsetup.target", "requires", n);
 119                 if (r < 0)
 120                         return r;
 121
 122                 dmname = strjoina("dev-mapper-", e, ".device");
 123                 r = generator_add_symlink(arg_dest, dmname, "requires", n);
 124                 if (r < 0)
 125                         return r;
 126         }
 127
 128         free(p);
 129         p = strjoin(arg_dest, "/dev-mapper-", e, ".device.d/50-job-timeout-sec-0.conf");
 130         if (!p)
 131                 return log_oom();
 132
 133         mkdir_parents_label(p, 0755);
 134         r = write_string_file(p,
 135                         "# Automatically generated by systemd-gpt-auto-generator\n\n"
 136                         "[Unit]\n"
 137                         "JobTimeoutSec=0\n",
 138                         WRITE_STRING_FILE_CREATE); /* the binary handles timeouts anyway */
 139         if (r < 0)
 140                 return log_error_errno(r, "Failed to write device drop-in: %m");
 141
 142         ret = strappend("/dev/mapper/", id);
 143         if (!ret)
 144                 return log_oom();
 145
 146         if (device)
 147                 *device = ret;
 148         return 0;
 149 }
 150
 151 static int add_mount(
 152                 const char *id,
 153                 const char *what,
 154                 const char *where,
 155                 const char *fstype,
 156                 bool rw,
 157                 const char *options,
 158                 const char *description,
 159                 const char *post) {
 160
 161         _cleanup_free_ char *unit = NULL, *crypto_what = NULL, *p = NULL;
 162         _cleanup_fclose_ FILE *f = NULL;
 163         int r;
 164
 165         /* Note that we don't apply specifier escaping on the input strings here, since we know they are not configured
 166          * externally, but all originate from our own sources here, and hence we know they contain no % characters that
 167          * could potentially be understood as specifiers. */
 168
 169         assert(id);
 170         assert(what);
 171         assert(where);
 172         assert(description);
 173
 174         log_debug("Adding %s: %s %s", where, what, strna(fstype));
 175
 176         if (streq_ptr(fstype, "crypto_LUKS")) {
 177
 178                 r = add_cryptsetup(id, what, rw, true, &crypto_what);
 179                 if (r < 0)
 180                         return r;
 181
 182                 what = crypto_what;
 183                 fstype = NULL;
 184         }
 185
 186         r = unit_name_from_path(where, ".mount", &unit);
 187         if (r < 0)
 188                 return log_error_errno(r, "Failed to generate unit name: %m");
 189
 190         p = strjoin(arg_dest, "/", unit);
 191         if (!p)
 192                 return log_oom();
 193
 194         f = fopen(p, "wxe");
 195         if (!f)
 196                 return log_error_errno(errno, "Failed to create unit file %s: %m", unit);
 197
 198         fprintf(f,
 199                 "# Automatically generated by systemd-gpt-auto-generator\n\n"
 200                 "[Unit]\n"
 201                 "Description=%s\n"
 202                 "Documentation=man:systemd-gpt-auto-generator(8)\n",
 203                 description);
 204
 205         if (post)
 206                 fprintf(f, "Before=%s\n", post);
 207
 208         r = generator_write_fsck_deps(f, arg_dest, what, where, fstype);
 209         if (r < 0)
 210                 return r;
 211
 212         fprintf(f,
 213                 "\n"
 214                 "[Mount]\n"
 215                 "What=%s\n"
 216                 "Where=%s\n",
 217                 what, where);
 218
 219         if (fstype)
 220                 fprintf(f, "Type=%s\n", fstype);
 221
 222         if (options)
 223                 fprintf(f, "Options=%s,%s\n", options, rw ? "rw" : "ro");
 224         else
 225                 fprintf(f, "Options=%s\n", rw ? "rw" : "ro");
 226
 227         r = fflush_and_check(f);
 228         if (r < 0)
 229                 return log_error_errno(r, "Failed to write unit file %s: %m", p);
 230
 231         if (post)
 232                 return generator_add_symlink(arg_dest, post, "requires", unit);
 233         return 0;
 234 }
 235
 236 static bool path_is_busy(const char *where) {
 237         int r;
 238
 239         /* already a mountpoint; generators run during reload */
 240         r = path_is_mount_point(where, NULL, AT_SYMLINK_FOLLOW);
 241         if (r > 0)
 242                 return false;
 243
 244         /* the directory might not exist on a stateless system */
 245         if (r == -ENOENT)
 246                 return false;
 247
 248         if (r < 0)
 249                 return true;
 250
 251         /* not a mountpoint but it contains files */
 252         if (dir_is_empty(where) <= 0)
 253                 return true;
 254
 255         return false;
 256 }
 257
 258 static int add_partition_mount(
 259                 DissectedPartition *p,
 260                 const char *id,
 261                 const char *where,
 262                 const char *description) {
 263
 264         assert(p);
 265
 266         if (path_is_busy(where)) {
 267                 log_debug("%s already populated, ignoring.", where);
 268                 return 0;
 269         }
 270
 271         return add_mount(
 272                         id,
 273                         p->node,
 274                         where,
 275                         p->fstype,
 276                         p->rw,
 277                         NULL,
 278                         description,
 279                         SPECIAL_LOCAL_FS_TARGET);
 280 }
 281
 282 static int add_swap(const char *path) {
 283         _cleanup_free_ char *name = NULL, *unit = NULL;
 284         _cleanup_fclose_ FILE *f = NULL;
 285         int r;
 286
 287         assert(path);
 288
 289         /* Disable the swap auto logic if at least one swap is defined in /etc/fstab, see #6192. */
 290         r = fstab_has_fstype("swap");
 291         if (r < 0)
 292                 return log_error_errno(r, "Failed to parse fstab: %m");
 293         if (r > 0) {
 294                 log_debug("swap specified in fstab, ignoring.");
 295                 return 0;
 296         }
 297
 298         log_debug("Adding swap: %s", path);
 299
 300         r = unit_name_from_path(path, ".swap", &name);
 301         if (r < 0)
 302                 return log_error_errno(r, "Failed to generate unit name: %m");
 303
 304         unit = strjoin(arg_dest, "/", name);
 305         if (!unit)
 306                 return log_oom();
 307
 308         f = fopen(unit, "wxe");
 309         if (!f)
 310                 return log_error_errno(errno, "Failed to create unit file %s: %m", unit);
 311
 312         fprintf(f,
 313                 "# Automatically generated by systemd-gpt-auto-generator\n\n"
 314                 "[Unit]\n"
 315                 "Description=Swap Partition\n"
 316                 "Documentation=man:systemd-gpt-auto-generator(8)\n\n"
 317                 "[Swap]\n"
 318                 "What=%s\n",
 319                 path);
 320
 321         r = fflush_and_check(f);
 322         if (r < 0)
 323                 return log_error_errno(r, "Failed to write unit file %s: %m", unit);
 324
 325         return generator_add_symlink(arg_dest, SPECIAL_SWAP_TARGET, "wants", name);
 326 }
 327
 328 #if ENABLE_EFI
 329 static int add_automount(
 330                 const char *id,
 331                 const char *what,
 332                 const char *where,
 333                 const char *fstype,
 334                 bool rw,
 335                 const char *options,
 336                 const char *description,
 337                 usec_t timeout) {
 338
 339         _cleanup_free_ char *unit = NULL;
 340         _cleanup_free_ char *opt, *p = NULL;
 341         _cleanup_fclose_ FILE *f = NULL;
 342         int r;
 343
 344         assert(id);
 345         assert(where);
 346         assert(description);
 347
 348         if (options)
 349                 opt = strjoin(options, ",noauto");
 350         else
 351                 opt = strdup("noauto");
 352         if (!opt)
 353                 return log_oom();
 354
 355         r = add_mount(id,
 356                       what,
 357                       where,
 358                       fstype,
 359                       rw,
 360                       opt,
 361                       description,
 362                       NULL);
 363         if (r < 0)
 364                 return r;
 365
 366         r = unit_name_from_path(where, ".automount", &unit);
 367         if (r < 0)
 368                 return log_error_errno(r, "Failed to generate unit name: %m");
 369
 370         p = strjoin(arg_dest, "/", unit);
 371         if (!p)
 372                 return log_oom();
 373
 374         f = fopen(p, "wxe");
 375         if (!f)
 376                 return log_error_errno(errno, "Failed to create unit file %s: %m", unit);
 377
 378         fprintf(f,
 379                 "# Automatically generated by systemd-gpt-auto-generator\n\n"
 380                 "[Unit]\n"
 381                 "Description=%s\n"
 382                 "Documentation=man:systemd-gpt-auto-generator(8)\n"
 383                 "[Automount]\n"
 384                 "Where=%s\n"
 385                 "TimeoutIdleSec="USEC_FMT"\n",
 386                 description,
 387                 where,
 388                 timeout / USEC_PER_SEC);
 389
 390         r = fflush_and_check(f);
 391         if (r < 0)
 392                 return log_error_errno(r, "Failed to write unit file %s: %m", p);
 393
 394         return generator_add_symlink(arg_dest, SPECIAL_LOCAL_FS_TARGET, "wants", unit);
 395 }
 396
 397 static int add_esp(DissectedPartition *p) {
 398         const char *esp;
 399         int r;
 400
 401         assert(p);
 402
 403         if (in_initrd()) {
 404                 log_debug("In initrd, ignoring the ESP.");
 405                 return 0;
 406         }
 407
 408         /* If /efi exists we'll use that. Otherwise we'll use /boot, as that's usually the better choice */
 409         esp = access("/efi/", F_OK) >= 0 ? "/efi" : "/boot";
 410
 411         /* We create an .automount which is not overridden by the .mount from the fstab generator. */
 412         r = fstab_is_mount_point(esp);
 413         if (r < 0)
 414                 return log_error_errno(r, "Failed to parse fstab: %m");
 415         if (r > 0) {
 416                 log_debug("%s specified in fstab, ignoring.", esp);
 417                 return 0;
 418         }
 419
 420         if (path_is_busy(esp)) {
 421                 log_debug("%s already populated, ignoring.", esp);
 422                 return 0;
 423         }
 424
 425         if (is_efi_boot()) {
 426                 sd_id128_t loader_uuid;
 427
 428                 /* If this is an EFI boot, be extra careful, and only mount the ESP if it was the ESP used for booting. */
 429
 430                 r = efi_loader_get_device_part_uuid(&loader_uuid);
 431                 if (r == -ENOENT) {
 432                         log_debug("EFI loader partition unknown.");
 433                         return 0;
 434                 }
 435                 if (r < 0)
 436                         return log_error_errno(r, "Failed to read ESP partition UUID: %m");
 437
 438                 if (!sd_id128_equal(p->uuid, loader_uuid)) {
 439                         log_debug("Partition for %s does not appear to be the partition we are booted from.", esp);
 440                         return 0;
 441                 }
 442         } else
 443                 log_debug("Not an EFI boot, skipping ESP check.");
 444
 445         return add_automount("boot",
 446                              p->node,
 447                              esp,
 448                              p->fstype,
 449                              true,
 450                              "umask=0077",
 451                              "EFI System Partition Automount",
 452                              120 * USEC_PER_SEC);
 453 }
 454 #else
 455 static int add_esp(DissectedPartition *p) {
 456         return 0;
 457 }
 458 #endif
 459
 460 static int open_parent(dev_t devnum, int *ret) {
 461         _cleanup_udev_device_unref_ struct udev_device *d = NULL;
 462         _cleanup_udev_unref_ struct udev *udev = NULL;
 463         const char *name, *devtype, *node;
 464         struct udev_device *parent;
 465         dev_t pn;
 466         int fd;
 467
 468         assert(ret);
 469
 470         udev = udev_new();
 471         if (!udev)
 472                 return log_oom();
 473
 474         d = udev_device_new_from_devnum(udev, 'b', devnum);
 475         if (!d)
 476                 return log_oom();
 477
 478         name = udev_device_get_devnode(d);
 479         if (!name)
 480                 name = udev_device_get_syspath(d);
 481         if (!name) {
 482                 log_debug("Device %u:%u does not have a name, ignoring.", major(devnum), minor(devnum));
 483                 goto not_found;
 484         }
 485
 486         parent = udev_device_get_parent(d);
 487         if (!parent) {
 488                 log_debug("%s: not a partitioned device, ignoring.", name);
 489                 goto not_found;
 490         }
 491
 492         /* Does it have a devtype? */
 493         devtype = udev_device_get_devtype(parent);
 494         if (!devtype) {
 495                 log_debug("%s: parent doesn't have a device type, ignoring.", name);
 496                 goto not_found;
 497         }
 498
 499         /* Is this a disk or a partition? We only care for disks... */
 500         if (!streq(devtype, "disk")) {
 501                 log_debug("%s: parent isn't a raw disk, ignoring.", name);
 502                 goto not_found;
 503         }
 504
 505         /* Does it have a device node? */
 506         node = udev_device_get_devnode(parent);
 507         if (!node) {
 508                 log_debug("%s: parent device does not have device node, ignoring.", name);
 509                 goto not_found;
 510         }
 511
 512         log_debug("%s: root device %s.", name, node);
 513
 514         pn = udev_device_get_devnum(parent);
 515         if (major(pn) == 0) {
 516                 log_debug("%s: parent device is not a proper block device, ignoring.", name);
 517                 goto not_found;
 518         }
 519
 520         fd = open(node, O_RDONLY|O_CLOEXEC|O_NOCTTY);
 521         if (fd < 0)
 522                 return log_error_errno(errno, "Failed to open %s: %m", node);
 523
 524         *ret = fd;
 525         return 1;
 526
 527 not_found:
 528         *ret = -1;
 529         return 0;
 530 }
 531
 532 static int enumerate_partitions(dev_t devnum) {
 533
 534         _cleanup_close_ int fd = -1;
 535         _cleanup_(dissected_image_unrefp) DissectedImage *m = NULL;
 536         int r, k;
 537
 538         r = open_parent(devnum, &fd);
 539         if (r <= 0)
 540                 return r;
 541
 542         r = dissect_image(fd, NULL, 0, DISSECT_IMAGE_GPT_ONLY, &m);
 543         if (r == -ENOPKG) {
 544                 log_debug_errno(r, "No suitable partition table found, ignoring.");
 545                 return 0;
 546         }
 547         if (r < 0)
 548                 return log_error_errno(r, "Failed to dissect: %m");
 549
 550         if (m->partitions[PARTITION_SWAP].found) {
 551                 k = add_swap(m->partitions[PARTITION_SWAP].node);
 552                 if (k < 0)
 553                         r = k;
 554         }
 555
 556         if (m->partitions[PARTITION_ESP].found) {
 557                 k = add_esp(m->partitions + PARTITION_ESP);
 558                 if (k < 0)
 559                         r = k;
 560         }
 561
 562         if (m->partitions[PARTITION_HOME].found) {
 563                 k = add_partition_mount(m->partitions + PARTITION_HOME, "home", "/home", "Home Partition");
 564                 if (k < 0)
 565                         r = k;
 566         }
 567
 568         if (m->partitions[PARTITION_SRV].found) {
 569                 k = add_partition_mount(m->partitions + PARTITION_SRV, "srv", "/srv", "Server Data Partition");
 570                 if (k < 0)
 571                         r = k;
 572         }
 573
 574         return r;
 575 }
 576
 577 static int parse_proc_cmdline_item(const char *key, const char *value, void *data) {
 578         int r;
 579
 580         assert(key);
 581
 582         if (STR_IN_SET(key, "systemd.gpt_auto", "rd.systemd.gpt_auto")) {
 583
 584                 r = value ? parse_boolean(value) : 1;
 585                 if (r < 0)
 586                         log_warning("Failed to parse gpt-auto switch \"%s\". Ignoring.", value);
 587                 else
 588                         arg_enabled = r;
 589
 590         } else if (streq(key, "root")) {
 591
 592                 if (proc_cmdline_value_missing(key, value))
 593                         return 0;
 594
 595                 /* Disable root disk logic if there's a root= value
 596                  * specified (unless it happens to be "gpt-auto") */
 597
 598                 arg_root_enabled = streq(value, "gpt-auto");
 599
 600         } else if (streq(key, "roothash")) {
 601
 602                 if (proc_cmdline_value_missing(key, value))
 603                         return 0;
 604
 605                 /* Disable root disk logic if there's roothash= defined (i.e. verity enabled) */
 606
 607                 arg_root_enabled = false;
 608
 609         } else if (streq(key, "rw") && !value)
 610                 arg_root_rw = true;
 611         else if (streq(key, "ro") && !value)
 612                 arg_root_rw = false;
 613
 614         return 0;
 615 }
 616
 617 #if ENABLE_EFI
 618 static int add_root_cryptsetup(void) {
 619
 620         /* If a device /dev/gpt-auto-root-luks appears, then make it pull in systemd-cryptsetup-root.service, which
 621          * sets it up, and causes /dev/gpt-auto-root to appear which is all we are looking for. */
 622
 623         return add_cryptsetup("root", "/dev/gpt-auto-root-luks", true, false, NULL);
 624 }
 625 #endif
 626
 627 static int add_root_mount(void) {
 628
 629 #if ENABLE_EFI
 630         int r;
 631
 632         if (!is_efi_boot()) {
 633                 log_debug("Not a EFI boot, not creating root mount.");
 634                 return 0;
 635         }
 636
 637         r = efi_loader_get_device_part_uuid(NULL);
 638         if (r == -ENOENT) {
 639                 log_debug("EFI loader partition unknown, exiting.");
 640                 return 0;
 641         } else if (r < 0)
 642                 return log_error_errno(r, "Failed to read ESP partition UUID: %m");
 643
 644         /* OK, we have an ESP partition, this is fantastic, so let's
 645          * wait for a root device to show up. A udev rule will create
 646          * the link for us under the right name. */
 647
 648         if (in_initrd()) {
 649                 r = generator_write_initrd_root_device_deps(arg_dest, "/dev/gpt-auto-root");
 650                 if (r < 0)
 651                         return 0;
 652
 653                 r = add_root_cryptsetup();
 654                 if (r < 0)
 655                         return r;
 656         }
 657
 658         return add_mount(
 659                         "root",
 660                         "/dev/gpt-auto-root",
 661                         in_initrd() ? "/sysroot" : "/",
 662                         NULL,
 663                         arg_root_rw,
 664                         NULL,
 665                         "Root Partition",
 666                         in_initrd() ? SPECIAL_INITRD_ROOT_FS_TARGET : SPECIAL_LOCAL_FS_TARGET);
 667 #else
 668         return 0;
 669 #endif
 670 }
 671
 672 static int add_mounts(void) {
 673         dev_t devno;
 674         int r;
 675
 676         r = get_block_device_harder("/", &devno);
 677         if (r < 0)
 678                 return log_error_errno(r, "Failed to determine block device of root file system: %m");
 679         if (r == 0) {
 680                 r = get_block_device_harder("/usr", &devno);
 681                 if (r < 0)
 682                         return log_error_errno(r, "Failed to determine block device of /usr file system: %m");
 683                 if (r == 0) {
 684                         log_debug("Neither root nor /usr file system are on a (single) block device.");
 685                         return 0;
 686                 }
 687         }
 688
 689         return enumerate_partitions(devno);
 690 }
 691
 692 int main(int argc, char *argv[]) {
 693         int r, k;
 694
 695         if (argc > 1 && argc != 4) {
 696                 log_error("This program takes three or no arguments.");
 697                 return EXIT_FAILURE;
 698         }
 699
 700         if (argc > 1)
 701                 arg_dest = argv[3];
 702
 703         log_set_prohibit_ipc(true);
 704         log_set_target(LOG_TARGET_AUTO);
 705         log_parse_environment();
 706         log_open();
 707
 708         umask(0022);
 709
 710         if (detect_container() > 0) {
 711                 log_debug("In a container, exiting.");
 712                 return EXIT_SUCCESS;
 713         }
 714
 715         r = proc_cmdline_parse(parse_proc_cmdline_item, NULL, 0);
 716         if (r < 0)
 717                 log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m");
 718
 719         if (!arg_enabled) {
 720                 log_debug("Disabled, exiting.");
 721                 return EXIT_SUCCESS;
 722         }
 723
 724         if (arg_root_enabled)
 725                 r = add_root_mount();
 726         else
 727                 r = 0;
 728
 729         if (!in_initrd()) {
 730                 k = add_mounts();
 731                 if (k < 0)
 732                         r = k;
 733         }
 734
 735         return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 736 }