summaryrefslogtreecommitdiffstats
path: root/src/shared/generator.c
blob: 1eccc5a2895b991fa592e84e465e092bf722db6c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
/* SPDX-License-Identifier: LGPL-2.1-or-later */

#include <errno.h>
#include <unistd.h>

#include "alloc-util.h"
#include "cgroup-util.h"
#include "dropin.h"
#include "escape.h"
#include "fd-util.h"
#include "fileio.h"
#include "fstab-util.h"
#include "generator.h"
#include "log.h"
#include "macro.h"
#include "mkdir.h"
#include "path-util.h"
#include "special.h"
#include "specifier.h"
#include "string-util.h"
#include "time-util.h"
#include "unit-name.h"
#include "util.h"

int generator_open_unit_file(
                const char *dest,
                const char *source,
                const char *name,
                FILE **file) {

        const char *unit;
        FILE *f;
        int r;

        unit = prefix_roota(dest, name);

        r = fopen_unlocked(unit, "wxe", &f);
        if (r < 0) {
                if (source && r == -EEXIST)
                        return log_error_errno(r,
                                               "Failed to create unit file %s, as it already exists. Duplicate entry in %s?",
                                               unit, source);
                else
                        return log_error_errno(r,
                                               "Failed to create unit file %s: %m",
                                               unit);
        }

        fprintf(f,
                "# Automatically generated by %s\n\n",
                program_invocation_short_name);

        *file = f;
        return 0;
}

int generator_add_symlink(const char *dir, const char *dst, const char *dep_type, const char *src) {
        /* Adds a symlink from <dst>.<dep_type>/ to <src> (if src is absolute)
         * or ../<src> (otherwise). */

        const char *from, *to;

        from = path_is_absolute(src) ? src : strjoina("../", src);
        to = strjoina(dir, "/", dst, ".", dep_type, "/", basename(src));

        mkdir_parents_label(to, 0755);
        if (symlink(from, to) < 0)
                if (errno != EEXIST)
                        return log_error_errno(errno, "Failed to create symlink \"%s\": %m", to);

        return 0;
}

static int write_fsck_sysroot_service(const char *dir, const char *what) {
        _cleanup_free_ char *device = NULL, *escaped = NULL, *escaped2 = NULL;
        _cleanup_fclose_ FILE *f = NULL;
        const char *unit;
        int r;

        escaped = specifier_escape(what);
        if (!escaped)
                return log_oom();

        escaped2 = cescape(escaped);
        if (!escaped2)
                return log_oom();

        unit = strjoina(dir, "/"SPECIAL_FSCK_ROOT_SERVICE);
        log_debug("Creating %s", unit);

        r = unit_name_from_path(what, ".device", &device);
        if (r < 0)
                return log_error_errno(r, "Failed to convert device \"%s\" to unit name: %m", what);

        f = fopen(unit, "wxe");
        if (!f)
                return log_error_errno(errno, "Failed to create unit file %s: %m", unit);

        fprintf(f,
                "# Automatically generated by %1$s\n\n"
                "[Unit]\n"
                "Description=File System Check on %2$s\n"
                "Documentation=man:systemd-fsck-root.service(8)\n"
                "DefaultDependencies=no\n"
                "BindsTo=%3$s\n"
                "Conflicts=shutdown.target\n"
                "After=initrd-root-device.target local-fs-pre.target %3$s\n"
                "Before=shutdown.target\n"
                "\n"
                "[Service]\n"
                "Type=oneshot\n"
                "RemainAfterExit=yes\n"
                "ExecStart=" SYSTEMD_FSCK_PATH " %4$s\n"
                "TimeoutSec=0\n",
                program_invocation_short_name,
                escaped,
                device,
                escaped2);

        r = fflush_and_check(f);
        if (r < 0)
                return log_error_errno(r, "Failed to write unit file %s: %m", unit);

        return 0;
}

int generator_write_fsck_deps(
                FILE *f,
                const char *dir,
                const char *what,
                const char *where,
                const char *fstype) {

        int r;

        assert(f);
        assert(dir);
        assert(what);
        assert(where);

        if (!is_device_path(what)) {
                log_warning("Checking was requested for \"%s\", but it is not a device.", what);
                return 0;
        }

        if (!isempty(fstype) && !streq(fstype, "auto")) {
                r = fsck_exists(fstype);
                if (r < 0)
                        log_warning_errno(r, "Checking was requested for %s, but couldn't detect if fsck.%s may be used, proceeding: %m", what, fstype);
                else if (r == 0) {
                        /* treat missing check as essentially OK */
                        log_debug("Checking was requested for %s, but fsck.%s does not exist.", what, fstype);
                        return 0;
                }
        }

        if (path_equal(where, "/")) {
                const char *lnk;

                lnk = strjoina(dir, "/" SPECIAL_LOCAL_FS_TARGET ".wants/" SPECIAL_FSCK_ROOT_SERVICE);

                (void) mkdir_parents(lnk, 0755);
                if (symlink(SYSTEM_DATA_UNIT_PATH "/" SPECIAL_FSCK_ROOT_SERVICE, lnk) < 0)
                        return log_error_errno(errno, "Failed to create symlink %s: %m", lnk);

        } else {
                _cleanup_free_ char *_fsck = NULL;
                const char *fsck, *dep;

                if (in_initrd() && path_equal(where, "/sysroot")) {
                        r = write_fsck_sysroot_service(dir, what);
                        if (r < 0)
                                return r;

                        fsck = SPECIAL_FSCK_ROOT_SERVICE;
                        dep = "Requires";
                } else {
                        /* When this is /usr, then let's add a Wants= dependency, otherwise a Requires=
                         * dependency. Why? We can't possibly unmount /usr during shutdown, but if we have a
                         * Requires= from /usr onto a fsck@.service unit and that unit is shut down, then
                         * we'd have to unmount /usr too.  */

                        dep = !in_initrd() && path_equal(where, "/usr") ? "Wants" : "Requires";

                        r = unit_name_from_path_instance("systemd-fsck", what, ".service", &_fsck);
                        if (r < 0)
                                return log_error_errno(r, "Failed to create fsck service name: %m");

                        fsck = _fsck;
                }

                fprintf(f,
                        "%1$s=%2$s\n"
                        "After=%2$s\n",
                        dep, fsck);
        }

        return 0;
}

int generator_write_timeouts(
                const char *dir,
                const char *what,
                const char *where,
                const char *opts,
                char **filtered) {

        /* Configure how long we wait for a device that backs a mount point or a
         * swap partition to show up. This is useful to support endless device timeouts
         * for devices that show up only after user input, like crypto devices. */

        _cleanup_free_ char *node = NULL, *unit = NULL, *timeout = NULL;
        usec_t u;
        int r;

        r = fstab_filter_options(opts, "comment=systemd.device-timeout\0"
                                       "x-systemd.device-timeout\0",
                                 NULL, &timeout, filtered);
        if (r <= 0)
                return r;

        r = parse_sec_fix_0(timeout, &u);
        if (r < 0) {
                log_warning("Failed to parse timeout for %s, ignoring: %s", where, timeout);
                return 0;
        }

        node = fstab_node_to_udev_node(what);
        if (!node)
                return log_oom();
        if (!is_device_path(node)) {
                log_warning("x-systemd.device-timeout ignored for %s", what);
                return 0;
        }

        r = unit_name_from_path(node, ".device", &unit);
        if (r < 0)
                return log_error_errno(r, "Failed to make unit name from path: %m");

        return write_drop_in_format(dir, unit, 50, "device-timeout",
                                    "# Automatically generated by %s\n"
                                    "# from supplied options \"%s\"\n\n"
                                    "[Unit]\n"
                                    "JobRunningTimeoutSec=%s",
                                    program_invocation_short_name,
                                    opts,
                                    timeout);
}

int generator_write_device_deps(
                const char *dir,
                const char *what,
                const char *where,
                const char *opts) {

        /* fstab records that specify _netdev option should apply the network
         * ordering on the actual device depending on network connection. If we
         * are not mounting real device (NFS, CIFS), we rely on _netdev effect
         * on the mount unit itself. */

        _cleanup_free_ char *node = NULL, *unit = NULL;
        int r;

        if (fstab_is_extrinsic(where, opts))
                return 0;

        if (!fstab_test_option(opts, "_netdev\0"))
                return 0;

        node = fstab_node_to_udev_node(what);
        if (!node)
                return log_oom();

        /* Nothing to apply dependencies to. */
        if (!is_device_path(node))
                return 0;

        r = unit_name_from_path(node, ".device", &unit);
        if (r < 0)
                return log_error_errno(r, "Failed to make unit name from path \"%s\": %m",
                                       node);

        /* See mount_add_default_dependencies for explanation why we create such
         * dependencies. */
        return write_drop_in_format(dir, unit, 50, "netdev-dependencies",
                                    "# Automatically generated by %s\n\n"
                                    "[Unit]\n"
                                    "After=" SPECIAL_NETWORK_ONLINE_TARGET " " SPECIAL_NETWORK_TARGET "\n"
                                    "Wants=" SPECIAL_NETWORK_ONLINE_TARGET "\n",
                                    program_invocation_short_name);
}

int generator_write_initrd_root_device_deps(const char *dir, const char *what) {
        _cleanup_free_ char *unit = NULL;
        int r;

        r = unit_name_from_path(what, ".device", &unit);
        if (r < 0)
                return log_error_errno(r, "Failed to make unit name from path \"%s\": %m",
                                       what);

        return write_drop_in_format(dir, SPECIAL_INITRD_ROOT_DEVICE_TARGET, 50, "root-device",
                                    "# Automatically generated by %s\n\n"
                                    "[Unit]\n"
                                    "Requires=%s\n"
                                    "After=%s",
                                    program_invocation_short_name,
                                    unit,
                                    unit);
}

int generator_hook_up_mkswap(
                const char *dir,
                const char *what) {

        _cleanup_free_ char *node = NULL, *unit = NULL, *escaped = NULL, *where_unit = NULL;
        _cleanup_fclose_ FILE *f = NULL;
        const char *unit_file;
        int r;

        node = fstab_node_to_udev_node(what);
        if (!node)
                return log_oom();

        /* Nothing to work on. */
        if (!is_device_path(node))
                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                       "Cannot format something that is not a device node: %s",
                                       node);

        r = unit_name_from_path_instance("systemd-mkswap", node, ".service", &unit);
        if (r < 0)
                return log_error_errno(r, "Failed to make unit instance name from path \"%s\": %m",
                                       node);

        unit_file = prefix_roota(dir, unit);
        log_debug("Creating %s", unit_file);

        escaped = cescape(node);
        if (!escaped)
                return log_oom();

        r = unit_name_from_path(what, ".swap", &where_unit);
        if (r < 0)
                return log_error_errno(r, "Failed to make unit name from path \"%s\": %m",
                                       what);

        f = fopen(unit_file, "wxe");
        if (!f)
                return log_error_errno(errno, "Failed to create unit file %s: %m",
                                       unit_file);

        fprintf(f,
                "# Automatically generated by %s\n\n"
                "[Unit]\n"
                "Description=Make Swap on %%f\n"
                "Documentation=man:systemd-mkswap@.service(8)\n"
                "DefaultDependencies=no\n"
                "BindsTo=%%i.device\n"
                "Conflicts=shutdown.target\n"
                "After=%%i.device\n"
                "Before=shutdown.target %s\n"
                "\n"
                "[Service]\n"
                "Type=oneshot\n"
                "RemainAfterExit=yes\n"
                "ExecStart="SYSTEMD_MAKEFS_PATH " swap %s\n"
                "TimeoutSec=0\n",
                program_invocation_short_name,
                where_unit,
                escaped);

        r = fflush_and_check(f);
        if (r < 0)
                return log_error_errno(r, "Failed to write unit file %s: %m", unit_file);

        return generator_add_symlink(dir, where_unit, "requires", unit);
}

int generator_hook_up_mkfs(
                const char *dir,
                const char *what,
                const char *where,
                const char *type) {

        _cleanup_free_ char *node = NULL, *unit = NULL, *escaped = NULL, *where_unit = NULL;
        _cleanup_fclose_ FILE *f = NULL;
        const char *unit_file;
        int r;

        node = fstab_node_to_udev_node(what);
        if (!node)
                return log_oom();

        /* Nothing to work on. */
        if (!is_device_path(node))
                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                       "Cannot format something that is not a device node: %s",
                                       node);

        if (!type || streq(type, "auto"))
                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                       "Cannot format partition %s, filesystem type is not specified",
                                       node);

        r = unit_name_from_path_instance("systemd-makefs", node, ".service", &unit);
        if (r < 0)
                return log_error_errno(r, "Failed to make unit instance name from path \"%s\": %m",
                                       node);

        unit_file = prefix_roota(dir, unit);
        log_debug("Creating %s", unit_file);

        escaped = cescape(node);
        if (!escaped)
                return log_oom();

        r = unit_name_from_path(where, ".mount", &where_unit);
        if (r < 0)
                return log_error_errno(r, "Failed to make unit name from path \"%s\": %m",
                                       where);

        f = fopen(unit_file, "wxe");
        if (!f)
                return log_error_errno(errno, "Failed to create unit file %s: %m",
                                       unit_file);

        fprintf(f,
                "# Automatically generated by %s\n\n"
                "[Unit]\n"
                "Description=Make File System on %%f\n"
                "Documentation=man:systemd-makefs@.service(8)\n"
                "DefaultDependencies=no\n"
                "BindsTo=%%i.device\n"
                "Conflicts=shutdown.target\n"
                "After=%%i.device\n"
                /* fsck might or might not be used, so let's be safe and order
                 * ourselves before both systemd-fsck@.service and the mount unit. */
                "Before=shutdown.target systemd-fsck@%%i.service %s\n"
                "\n"
                "[Service]\n"
                "Type=oneshot\n"
                "RemainAfterExit=yes\n"
                "ExecStart="SYSTEMD_MAKEFS_PATH " %s %s\n"
                "TimeoutSec=0\n",
                program_invocation_short_name,
                where_unit,
                type,
                escaped);
        // XXX: what about local-fs-pre.target?

        r = fflush_and_check(f);
        if (r < 0)
                return log_error_errno(r, "Failed to write unit file %s: %m", unit_file);

        return generator_add_symlink(dir, where_unit, "requires", unit);
}

int generator_hook_up_growfs(
                const char *dir,
                const char *where,
                const char *target) {

        _cleanup_free_ char *unit = NULL, *escaped = NULL, *where_unit = NULL;
        _cleanup_fclose_ FILE *f = NULL;
        const char *unit_file;
        int r;

        escaped = cescape(where);
        if (!escaped)
                return log_oom();

        r = unit_name_from_path_instance("systemd-growfs", where, ".service", &unit);
        if (r < 0)
                return log_error_errno(r, "Failed to make unit instance name from path \"%s\": %m",
                                       where);

        r = unit_name_from_path(where, ".mount", &where_unit);
        if (r < 0)
                return log_error_errno(r, "Failed to make unit name from path \"%s\": %m",
                                       where);

        unit_file = prefix_roota(dir, unit);
        log_debug("Creating %s", unit_file);

        f = fopen(unit_file, "wxe");
        if (!f)
                return log_error_errno(errno, "Failed to create unit file %s: %m",
                                       unit_file);

        fprintf(f,
                "# Automatically generated by %s\n\n"
                "[Unit]\n"
                "Description=Grow File System on %%f\n"
                "Documentation=man:systemd-growfs@.service(8)\n"
                "DefaultDependencies=no\n"
                "BindsTo=%%i.mount\n"
                "Conflicts=shutdown.target\n"
                "After=%%i.mount\n"
                "Before=shutdown.target %s\n",
                program_invocation_short_name,
                target);

        if (empty_or_root(where)) /* Make sure the root fs is actually writable before we resize it */
                fprintf(f,
                        "After=systemd-remount-fs.service\n");

        fprintf(f,
                "\n"
                "[Service]\n"
                "Type=oneshot\n"
                "RemainAfterExit=yes\n"
                "ExecStart="SYSTEMD_GROWFS_PATH " %s\n"
                "TimeoutSec=0\n",
                escaped);

        return generator_add_symlink(dir, where_unit, "wants", unit);
}

int generator_enable_remount_fs_service(const char *dir) {
        /* Pull in systemd-remount-fs.service */
        return generator_add_symlink(dir, SPECIAL_LOCAL_FS_TARGET, "wants",
                                     SYSTEM_DATA_UNIT_PATH "/" SPECIAL_REMOUNT_FS_SERVICE);
}

int generator_write_blockdev_dependency(
                FILE *f,
                const char *what) {

        _cleanup_free_ char *escaped = NULL;
        int r;

        assert(f);
        assert(what);

        if (!path_startswith(what, "/dev/"))
                return 0;

        r = unit_name_path_escape(what, &escaped);
        if (r < 0)
                return log_error_errno(r, "Failed to escape device node path %s: %m", what);

        fprintf(f,
                "After=blockdev@%s.target\n",
                escaped);

        return 0;
}

int generator_write_cryptsetup_unit_section(
                FILE *f,
                const char *source) {

        assert(f);

        fprintf(f,
                "[Unit]\n"
                "Description=Cryptography Setup for %%I\n"
                "Documentation=man:crypttab(5) man:systemd-cryptsetup-generator(8) man:systemd-cryptsetup@.service(8)\n");

        if (source)
                fprintf(f, "SourcePath=%s\n", source);

        fprintf(f,
                "DefaultDependencies=no\n"
                "IgnoreOnIsolate=true\n"
                "After=cryptsetup-pre.target systemd-udevd-kernel.socket\n"
                "Before=blockdev@dev-mapper-%%i.target\n"
                "Wants=blockdev@dev-mapper-%%i.target\n");

        return 0;
}

int generator_write_cryptsetup_service_section(
                FILE *f,
                const char *name,
                const char *what,
                const char *password,
                const char *options) {

        _cleanup_free_ char *name_escaped = NULL, *what_escaped = NULL, *password_escaped = NULL, *options_escaped = NULL;

        assert(f);
        assert(name);
        assert(what);

        name_escaped = specifier_escape(name);
        if (!name_escaped)
                return log_oom();

        what_escaped = specifier_escape(what);
        if (!what_escaped)
                return log_oom();

        if (password) {
                password_escaped = specifier_escape(password);
                if (!password_escaped)
                        return log_oom();
        }

        if (options) {
                options_escaped = specifier_escape(options);
                if (!options_escaped)
                        return log_oom();
        }

        fprintf(f,
                "\n"
                "[Service]\n"
                "Type=oneshot\n"
                "RemainAfterExit=yes\n"
                "TimeoutSec=0\n"          /* The binary handles timeouts on its own */
                "KeyringMode=shared\n"    /* Make sure we can share cached keys among instances */
                "OOMScoreAdjust=500\n"    /* Unlocking can allocate a lot of memory if Argon2 is used */
                "ExecStart=" SYSTEMD_CRYPTSETUP_PATH " attach '%s' '%s' '%s' '%s'\n"
                "ExecStop=" SYSTEMD_CRYPTSETUP_PATH " detach '%s'\n",
                name_escaped, what_escaped, strempty(password_escaped), strempty(options_escaped),
                name_escaped);

        return 0;
}

void log_setup_generator(void) {
        /* Disable talking to syslog/journal (i.e. the two IPC-based loggers) if we run in system context. */
        if (cg_pid_get_owner_uid(0, NULL) == -ENXIO /* not running in a per-user slice */)
                log_set_prohibit_ipc(true);

        log_set_target(LOG_TARGET_JOURNAL_OR_KMSG); /* This effectively means: journal for per-user generators, kmsg otherwise */
        log_parse_environment();
        (void) log_open();
}