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jail: fix various ignoring return value compilation warning
[project/procd.git] / jail / jail.c
1 /*
2 * Copyright (C) 2015 John Crispin <blogic@openwrt.org>
3 * Copyright (C) 2020 Daniel Golle <daniel@makrotopia.org>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU Lesser General Public License version 2.1
7 * as published by the Free Software Foundation
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 */
14
15 #define _GNU_SOURCE
16 #include <sys/mount.h>
17 #include <sys/prctl.h>
18 #include <sys/wait.h>
19 #include <sys/types.h>
20 #include <sys/time.h>
21 #include <sys/resource.h>
22 #include <sys/stat.h>
23 #include <sys/sysmacros.h>
24
25 /* musl only defined 15 limit types, make sure all 16 are supported */
26 #ifndef RLIMIT_RTTIME
27 #define RLIMIT_RTTIME 15
28 #undef RLIMIT_NLIMITS
29 #define RLIMIT_NLIMITS 16
30 #undef RLIM_NLIMITS
31 #define RLIM_NLIMITS 16
32 #endif
33
34 #include <assert.h>
35 #include <stdlib.h>
36 #include <unistd.h>
37 #include <errno.h>
38 #include <pwd.h>
39 #include <grp.h>
40 #include <string.h>
41 #include <fcntl.h>
42 #include <sched.h>
43 #include <linux/filter.h>
44 #include <linux/limits.h>
45 #include <linux/nsfs.h>
46 #include <linux/securebits.h>
47 #include <signal.h>
48 #include <inttypes.h>
49
50 #include "capabilities.h"
51 #include "elf.h"
52 #include "fs.h"
53 #include "jail.h"
54 #include "log.h"
55 #include "seccomp-oci.h"
56 #include "cgroups.h"
57 #include "netifd.h"
58
59 #include <libubox/blobmsg.h>
60 #include <libubox/blobmsg_json.h>
61 #include <libubox/list.h>
62 #include <libubox/vlist.h>
63 #include <libubox/uloop.h>
64 #include <libubox/utils.h>
65 #include <libubus.h>
66
67 #ifndef CLONE_NEWCGROUP
68 #define CLONE_NEWCGROUP 0x02000000
69 #endif
70
71 #define STACK_SIZE (1024 * 1024)
72 #define OPT_ARGS "cC:d:e:EfFG:h:ij:J:ln:NoO:pP:r:R:sS:uU:w:t:T:y"
73
74 #define OCI_VERSION_STRING "1.0.2"
75
76 struct hook_execvpe {
77 char *file;
78 char **argv;
79 char **envp;
80 int timeout;
81 };
82
83 struct sysctl_val {
84 char *entry;
85 char *value;
86 };
87
88 struct mknod_args {
89 char *path;
90 mode_t mode;
91 dev_t dev;
92 uid_t uid;
93 gid_t gid;
94 };
95
96 static struct {
97 char *name;
98 char *hostname;
99 char **jail_argv;
100 char *cwd;
101 char *seccomp;
102 struct sock_fprog *ociseccomp;
103 char *capabilities;
104 struct jail_capset capset;
105 char *user;
106 char *group;
107 char *extroot;
108 char *overlaydir;
109 char *tmpoverlaysize;
110 char **envp;
111 char *uidmap;
112 char *gidmap;
113 char *pidfile;
114 struct sysctl_val **sysctl;
115 int no_new_privs;
116 int namespace;
117 struct {
118 int pid;
119 int net;
120 int ns;
121 int ipc;
122 int uts;
123 int user;
124 int cgroup;
125 #ifdef CLONE_NEWTIME
126 int time;
127 #endif
128 } setns;
129 int procfs;
130 int ronly;
131 int sysfs;
132 int console;
133 int pw_uid;
134 int pw_gid;
135 int gr_gid;
136 int root_map_uid;
137 gid_t *additional_gids;
138 size_t num_additional_gids;
139 mode_t umask;
140 bool set_umask;
141 int require_jail;
142 struct {
143 struct hook_execvpe **createRuntime;
144 struct hook_execvpe **createContainer;
145 struct hook_execvpe **startContainer;
146 struct hook_execvpe **poststart;
147 struct hook_execvpe **poststop;
148 } hooks;
149 struct rlimit *rlimits[RLIM_NLIMITS];
150 int oom_score_adj;
151 bool set_oom_score_adj;
152 struct mknod_args **devices;
153 char *ocibundle;
154 bool immediately;
155 struct blob_attr *annotations;
156 int term_timeout;
157 } opts;
158
159 static struct blob_buf ocibuf;
160
161 extern int pivot_root(const char *new_root, const char *put_old);
162
163 int debug = 0;
164
165 static char child_stack[STACK_SIZE];
166
167 static struct ubus_context *parent_ctx;
168
169 int console_fd;
170
171
172 static inline bool has_namespaces(void)
173 {
174 return ((opts.setns.pid != -1) ||
175 (opts.setns.net != -1) ||
176 (opts.setns.ns != -1) ||
177 (opts.setns.ipc != -1) ||
178 (opts.setns.uts != -1) ||
179 (opts.setns.user != -1) ||
180 (opts.setns.cgroup != -1) ||
181 #ifdef CLONE_NEWTIME
182 (opts.setns.time != -1) ||
183 #endif
184 opts.namespace);
185 }
186
187 static void free_oci_envp(char **p) {
188 char **tmp;
189
190 if (p) {
191 tmp = p;
192 while (*tmp)
193 free(*(tmp++));
194
195 free(p);
196 }
197 }
198
199 static void free_hooklist(struct hook_execvpe **hooklist)
200 {
201 struct hook_execvpe *cur;
202
203 if (!hooklist)
204 return;
205
206 cur = *hooklist;
207 while (cur) {
208 free_oci_envp(cur->argv);
209 free_oci_envp(cur->envp);
210 free(cur->file);
211 free(cur++);
212 }
213 free(hooklist);
214 }
215
216 static void free_sysctl(void) {
217 struct sysctl_val *cur;
218 cur = *opts.sysctl;
219
220 while (cur) {
221 free(cur->entry);
222 free(cur->value);
223 free(cur++);
224 }
225 free(opts.sysctl);
226 }
227
228 static void free_devices(void) {
229 struct mknod_args **cur;
230
231 if (!opts.devices)
232 return;
233
234 cur = opts.devices;
235
236 while (*cur) {
237 free((*cur)->path);
238 free(*(cur++));
239 }
240 free(opts.devices);
241 }
242
243 static void free_rlimits(void) {
244 int type;
245
246 for (type = 0; type < RLIM_NLIMITS; ++type)
247 free(opts.rlimits[type]);
248 }
249
250 static void free_opts(bool parent) {
251
252 free_library_search();
253 mount_free();
254 cgroups_free();
255
256 /* we need to keep argv, envp and seccomp filter in child */
257 if (parent) { /* parent-only */
258 if (opts.ociseccomp) {
259 free(opts.ociseccomp->filter);
260 free(opts.ociseccomp);
261 }
262
263 free_oci_envp(opts.jail_argv);
264 free_oci_envp(opts.envp);
265 }
266
267 free_rlimits();
268 free_sysctl();
269 free_devices();
270 free(opts.hostname);
271 free(opts.cwd);
272 free(opts.uidmap);
273 free(opts.gidmap);
274 free(opts.annotations);
275 free(opts.extroot);
276 free(opts.overlaydir);
277 free_hooklist(opts.hooks.createRuntime);
278 free_hooklist(opts.hooks.createContainer);
279 free_hooklist(opts.hooks.startContainer);
280 free_hooklist(opts.hooks.poststart);
281 free_hooklist(opts.hooks.poststop);
282 }
283
284 static int mount_overlay(char *jail_root, char *overlaydir) {
285 char *upperdir, *workdir, *optsstr, *upperetc, *upperresolvconf;
286 const char mountoptsformat[] = "lowerdir=%s,upperdir=%s,workdir=%s";
287 int ret = -1, fd;
288
289 if (asprintf(&upperdir, "%s%s", overlaydir, "/upper") < 0)
290 goto out;
291
292 if (asprintf(&workdir, "%s%s", overlaydir, "/work") < 0)
293 goto upper_printf;
294
295 if (asprintf(&optsstr, mountoptsformat, jail_root, upperdir, workdir) < 0)
296 goto work_printf;
297
298 if (mkdir_p(upperdir, 0755) || mkdir_p(workdir, 0755))
299 goto opts_printf;
300
301 /*
302 * make sure /etc/resolv.conf exists in overlay and is owned by jail userns root
303 * this is to work-around a bug in overlayfs described in the overlayfs-userns
304 * patch:
305 * 3. modification of a file 'hithere' which is in l but not yet
306 * in u, and which is not owned by T, is not allowed, even if
307 * writes to u are allowed. This may be a bug in overlayfs,
308 * but it is safe behavior.
309 */
310 if (asprintf(&upperetc, "%s/etc", upperdir) < 0)
311 goto opts_printf;
312
313 if (mkdir_p(upperetc, 0755))
314 goto upper_etc_printf;
315
316 if (asprintf(&upperresolvconf, "%s/resolv.conf", upperetc) < 0)
317 goto upper_etc_printf;
318
319 fd = creat(upperresolvconf, 0644);
320 if (fd < 0) {
321 if (errno != EEXIST)
322 ERROR("creat(%s) failed: %m\n", upperresolvconf);
323 } else {
324 close(fd);
325 }
326 DEBUG("mount -t overlay %s %s (%s)\n", jail_root, jail_root, optsstr);
327
328 if (mount(jail_root, jail_root, "overlay", MS_NOATIME, optsstr))
329 goto upper_resolvconf_printf;
330
331 ret = 0;
332
333 upper_resolvconf_printf:
334 free(upperresolvconf);
335 upper_etc_printf:
336 free(upperetc);
337 opts_printf:
338 free(optsstr);
339 work_printf:
340 free(workdir);
341 upper_printf:
342 free(upperdir);
343 out:
344 return ret;
345 }
346
347 static void pass_console(int console_fd)
348 {
349 struct ubus_context *child_ctx = ubus_connect(NULL);
350 static struct blob_buf req;
351 uint32_t id;
352
353 if (!child_ctx)
354 return;
355
356 blob_buf_init(&req, 0);
357 blobmsg_add_string(&req, "name", opts.name);
358
359 if (ubus_lookup_id(child_ctx, "container", &id) ||
360 ubus_invoke_fd(child_ctx, id, "console_set", req.head, NULL, NULL, 3000, console_fd))
361 INFO("ubus request failed\n");
362 else
363 close(console_fd);
364
365 blob_buf_free(&req);
366 ubus_free(child_ctx);
367 }
368
369 static int create_dev_console(const char *jail_root)
370 {
371 char *console_fname;
372 char dev_console_path[PATH_MAX];
373 int slave_console_fd;
374
375 /* Open UNIX/98 virtual console */
376 console_fd = posix_openpt(O_RDWR | O_NOCTTY);
377 if (console_fd < 0)
378 return -1;
379
380 console_fname = ptsname(console_fd);
381 DEBUG("got console fd %d and PTS client name %s\n", console_fd, console_fname);
382 if (!console_fname)
383 goto no_console;
384
385 grantpt(console_fd);
386 unlockpt(console_fd);
387
388 /* pass PTY master to procd */
389 pass_console(console_fd);
390
391 /* mount-bind PTY slave to /dev/console in jail */
392 snprintf(dev_console_path, sizeof(dev_console_path), "%s/dev/console", jail_root);
393 close(creat(dev_console_path, 0620));
394
395 if (mount(console_fname, dev_console_path, "bind", MS_BIND, NULL))
396 goto no_console;
397
398 /* use PTY slave for stdio */
399 slave_console_fd = open(console_fname, O_RDWR); /* | O_NOCTTY */
400 if (slave_console_fd < 0)
401 goto no_console;
402
403 dup2(slave_console_fd, 0);
404 dup2(slave_console_fd, 1);
405 dup2(slave_console_fd, 2);
406 close(slave_console_fd);
407
408 INFO("using guest console %s\n", console_fname);
409
410 return 0;
411
412 no_console:
413 close(console_fd);
414 return 1;
415 }
416
417 static int hook_running = 0;
418 static int hook_return_code = 0;
419 static struct hook_execvpe **current_hook = NULL;
420 typedef void (*hook_return_handler)(void);
421 static hook_return_handler hook_return_cb = NULL;
422
423 static void hook_process_timeout_cb(struct uloop_timeout *t);
424 static struct uloop_timeout hook_process_timeout = {
425 .cb = hook_process_timeout_cb,
426 };
427
428 static void run_hooklist(void);
429 static void hook_process_handler(struct uloop_process *c, int ret)
430 {
431 uloop_timeout_cancel(&hook_process_timeout);
432
433 if (WIFEXITED(ret)) {
434 hook_return_code = WEXITSTATUS(ret);
435 if (hook_return_code)
436 ERROR("hook (%d) exited with exit: %d\n", c->pid, hook_return_code);
437 else
438 DEBUG("hook (%d) exited with exit: %d\n", c->pid, hook_return_code);
439
440 } else {
441 hook_return_code = WTERMSIG(ret);
442 ERROR("hook (%d) exited with signal: %d\n", c->pid, hook_return_code);
443 }
444 hook_running = 0;
445 ++current_hook;
446 run_hooklist();
447 }
448
449 static struct uloop_process hook_process = {
450 .cb = hook_process_handler,
451 };
452
453 static void hook_process_timeout_cb(struct uloop_timeout *t)
454 {
455 DEBUG("hook process failed to stop, sending SIGKILL\n");
456 kill(hook_process.pid, SIGKILL);
457 }
458
459 static void run_hooklist(void)
460 {
461 struct hook_execvpe *hook = *current_hook;
462 struct stat s;
463
464 if (!hook)
465 return hook_return_cb();
466
467 DEBUG("executing hook %s\n", hook->file);
468
469 if (stat(hook->file, &s))
470 hook_process_handler(&hook_process, ENOENT);
471
472 if (!((unsigned long)s.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH)))
473 hook_process_handler(&hook_process, EPERM);
474
475 hook_running = 1;
476 hook_process.pid = fork();
477 if (hook_process.pid == 0) {
478 /* child */
479 execve(hook->file, hook->argv, hook->envp);
480 ERROR("execve error %m\n");
481 _exit(errno);
482 } else if (hook_process.pid < 0) {
483 /* fork error */
484 ERROR("hook fork error\n");
485 hook_running = 0;
486 hook_process_handler(&hook_process, errno);
487 }
488
489 /* parent */
490 uloop_process_add(&hook_process);
491
492 if (hook->timeout > 0)
493 uloop_timeout_set(&hook_process_timeout, 1000 * hook->timeout);
494
495 uloop_run();
496 if (hook_running) {
497 DEBUG("uloop interrupted, killing jail process\n");
498 kill(hook_process.pid, SIGTERM);
499 uloop_timeout_set(&hook_process_timeout, 1000);
500 uloop_run();
501 }
502 }
503
504 static void run_hooks(struct hook_execvpe **hooklist, hook_return_handler return_cb)
505 {
506 if (!hooklist)
507 return_cb();
508
509 current_hook = hooklist;
510 hook_return_cb = return_cb;
511
512 run_hooklist();
513 }
514
515 static int apply_sysctl(const char *jail_root)
516 {
517 struct sysctl_val **cur;
518 char *procdir, *fname;
519 int f;
520
521 if (!opts.sysctl)
522 return 0;
523
524 if (asprintf(&procdir, "%s/proc", jail_root) < 0)
525 return ENOMEM;
526
527 mkdir(procdir, 0700);
528 if (mount("proc", procdir, "proc", MS_NOATIME | MS_NODEV | MS_NOEXEC | MS_NOSUID, 0))
529 return EPERM;
530
531 cur = opts.sysctl;
532
533 while (*cur) {
534 if (asprintf(&fname, "%s/sys/%s", procdir, (*cur)->entry) < 0)
535 return ENOMEM;
536
537 DEBUG("sysctl: writing '%s' to %s\n", (*cur)->value, fname);
538
539 f = open(fname, O_WRONLY);
540 if (f < 0) {
541 ERROR("sysctl: can't open %s\n", fname);
542 free(fname);
543 return errno;
544 }
545 if (write(f, (*cur)->value, strlen((*cur)->value)) < 0) {
546 ERROR("sysctl: write to %s\n", fname);
547 free(fname);
548 close(f);
549 return errno;
550 }
551
552 free(fname);
553 close(f);
554 ++cur;
555 }
556 umount(procdir);
557 rmdir(procdir);
558 free(procdir);
559
560 return 0;
561 }
562
563 /* glibc defines makedev calling a function. make sure it's a pure macro */
564 #if defined(__GLIBC__)
565 #undef makedev
566 /* from musl's sys/sysmacros.h */
567 #define makedev(x,y) ( \
568 (((x)&0xfffff000ULL) << 32) | \
569 (((x)&0x00000fffULL) << 8) | \
570 (((y)&0xffffff00ULL) << 12) | \
571 (((y)&0x000000ffULL)) )
572 #endif
573
574 static struct mknod_args default_devices[] = {
575 { .path = "/dev/null", .mode = (S_IFCHR|S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH), .dev = makedev(1, 3) },
576 { .path = "/dev/zero", .mode = (S_IFCHR|S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH), .dev = makedev(1, 5) },
577 { .path = "/dev/full", .mode = (S_IFCHR|S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH), .dev = makedev(1, 7) },
578 { .path = "/dev/random", .mode = (S_IFCHR|S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH), .dev = makedev(1, 8) },
579 { .path = "/dev/urandom", .mode = (S_IFCHR|S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH), .dev = makedev(1, 9) },
580 { .path = "/dev/tty", .mode = (S_IFCHR|S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP), .dev = makedev(5, 0), .gid = 5 },
581 { 0 },
582 };
583
584 static int create_devices(void)
585 {
586 struct mknod_args **cur, *curdef;
587 char *path, *tmp;
588 int ret;
589
590 if (!opts.devices)
591 goto only_default_devices;
592
593 cur = opts.devices;
594
595 while (*cur) {
596 path = (*cur)->path;
597 /* don't allow devices outside of /dev */
598 if (strncmp(path, "/dev", 4))
599 return EPERM;
600
601 /* make sure parent folder exists */
602 tmp = strrchr(path, '/');
603 if (!tmp)
604 return EINVAL;
605
606 *tmp = '\0';
607 if (strcmp(path, "/dev")) {
608 DEBUG("creating directory %s\n", path);
609
610 mkdir_p(path, 0755);
611 }
612 *tmp = '/';
613
614 DEBUG("creating %s (mode=%08o)\n", path, (*cur)->mode);
615
616 /* create device */
617 if (mknod(path, (*cur)->mode, (*cur)->dev))
618 return errno;
619
620 /* change owner, if needed */
621 if (((*cur)->uid || (*cur)->gid) &&
622 chown(path, (*cur)->uid, (*cur)->gid))
623 return errno;
624
625 ++cur;
626 }
627
628 only_default_devices:
629 curdef = default_devices;
630 while(curdef->path) {
631 DEBUG("creating %s (mode=%08o)\n", curdef->path, curdef->mode);
632 if (mknod(curdef->path, curdef->mode, curdef->dev)) {
633 ++curdef;
634 continue; /* may already exist, eg. due to a bind-mount */
635 }
636 if ((curdef->uid || curdef->gid) &&
637 chown(curdef->path, curdef->uid, curdef->gid))
638 return errno;
639
640 ++curdef;
641 }
642
643 /* Dev symbolic links as defined in OCI spec */
644 ret = symlink("/dev/pts/ptmx", "/dev/ptmx");
645 if (ret < 0)
646 WARNING("symlink() failed to create link to /dev/pts/ptmx");
647
648 ret = symlink("/proc/self/fd", "/dev/fd");
649 if (ret < 0)
650 WARNING("symlink() failed to create link to /proc/self/fd");
651
652 ret = symlink("/proc/self/fd/0", "/dev/stdin");
653 if (ret < 0)
654 WARNING("symlink() failed to create link to /proc/self/fd/0");
655
656 ret = symlink("/proc/self/fd/1", "/dev/stdout");
657 if (ret < 0)
658 WARNING("symlink() failed to create link to /proc/self/fd/1");
659
660 ret = symlink("/proc/self/fd/2", "/dev/stderr");
661 if (ret < 0)
662 WARNING("symlink() failed to create link to /proc/self/fd/2");
663
664 return 0;
665 }
666
667 static char jail_root[] = "/tmp/ujail-XXXXXX";
668 static char tmpovdir[] = "/tmp/ujail-overlay-XXXXXX";
669 static mode_t old_umask;
670 static void enter_jail_fs(void);
671 static int build_jail_fs(void)
672 {
673 char *overlaydir = NULL;
674 int ret;
675
676 old_umask = umask(0);
677
678 if (mkdtemp(jail_root) == NULL) {
679 ERROR("mkdtemp(%s) failed: %m\n", jail_root);
680 return -1;
681 }
682
683 if (apply_sysctl(jail_root)) {
684 ERROR("failed to apply sysctl values\n");
685 return -1;
686 }
687
688 /* oldroot can't be MS_SHARED else pivot_root() fails */
689 if (mount("none", "/", "none", MS_REC|MS_PRIVATE, NULL)) {
690 ERROR("private mount failed %m\n");
691 return -1;
692 }
693
694 if (opts.extroot) {
695 if (mount(opts.extroot, jail_root, "bind", MS_BIND, NULL)) {
696 ERROR("extroot mount failed %m\n");
697 return -1;
698 }
699 } else {
700 if (mount("tmpfs", jail_root, "tmpfs", MS_NOATIME, "mode=0755")) {
701 ERROR("tmpfs mount failed %m\n");
702 return -1;
703 }
704 }
705
706 if (opts.tmpoverlaysize) {
707 char mountoptsstr[] = "mode=0755,size=XXXXXXXX";
708
709 snprintf(mountoptsstr, sizeof(mountoptsstr),
710 "mode=0755,size=%s", opts.tmpoverlaysize);
711 if (mkdtemp(tmpovdir) == NULL) {
712 ERROR("mkdtemp(%s) failed: %m\n", jail_root);
713 return -1;
714 }
715 if (mount("tmpfs", tmpovdir, "tmpfs", MS_NOATIME,
716 mountoptsstr)) {
717 ERROR("failed to mount tmpfs for overlay (size=%s)\n", opts.tmpoverlaysize);
718 return -1;
719 }
720 overlaydir = tmpovdir;
721 }
722
723 if (opts.overlaydir)
724 overlaydir = opts.overlaydir;
725
726 if (overlaydir) {
727 ret = mount_overlay(jail_root, overlaydir);
728 if (ret)
729 return ret;
730 }
731
732 if (chdir(jail_root)) {
733 ERROR("chdir(%s) (jail_root) failed: %m\n", jail_root);
734 return -1;
735 }
736
737 if (mount_all(jail_root)) {
738 ERROR("mount_all() failed\n");
739 return -1;
740 }
741
742 if (opts.console)
743 create_dev_console(jail_root);
744
745 /* make sure /etc/resolv.conf exists if in new network namespace */
746 if (opts.namespace & CLONE_NEWNET) {
747 char jailetc[PATH_MAX], jaillink[PATH_MAX];
748
749 snprintf(jailetc, PATH_MAX, "%s/etc", jail_root);
750 mkdir_p(jailetc, 0755);
751 snprintf(jaillink, PATH_MAX, "%s/etc/resolv.conf", jail_root);
752 if (overlaydir)
753 unlink(jaillink);
754
755 ret = symlink("../dev/resolv.conf.d/resolv.conf.auto", jaillink);
756 if (ret < 0)
757 WARNING("symlink() failed to create link to ../dev/resolv.conf.d/resolv.conf.auto");
758 }
759
760 run_hooks(opts.hooks.createContainer, enter_jail_fs);
761
762 return 0;
763 }
764
765 static bool exit_from_child;
766 static void free_and_exit(int ret)
767 {
768 if (!exit_from_child && opts.ocibundle)
769 cgroups_free();
770
771 if (!exit_from_child && parent_ctx)
772 ubus_free(parent_ctx);
773
774 free_opts(!exit_from_child);
775
776 exit(ret);
777 }
778
779 static void post_jail_fs(void);
780 static void enter_jail_fs(void)
781 {
782 char dirbuf[sizeof(jail_root) + 4];
783
784 snprintf(dirbuf, sizeof(dirbuf), "%s/old", jail_root);
785 mkdir(dirbuf, 0755);
786
787 if (pivot_root(jail_root, dirbuf) == -1) {
788 ERROR("pivot_root(%s, %s) failed: %m\n", jail_root, dirbuf);
789 free_and_exit(-1);
790 }
791 if (chdir("/")) {
792 ERROR("chdir(/) (after pivot_root) failed: %m\n");
793 free_and_exit(-1);
794 }
795
796 snprintf(dirbuf, sizeof(dirbuf), "/old%s", jail_root);
797 umount2(dirbuf, MNT_DETACH);
798 rmdir(dirbuf);
799 if (opts.tmpoverlaysize) {
800 char tmpdirbuf[sizeof(tmpovdir) + 4];
801 snprintf(tmpdirbuf, sizeof(tmpdirbuf), "/old%s", tmpovdir);
802 umount2(tmpdirbuf, MNT_DETACH);
803 rmdir(tmpdirbuf);
804 }
805
806 umount2("/old", MNT_DETACH);
807 rmdir("/old");
808
809 if (create_devices()) {
810 ERROR("create_devices() failed\n");
811 free_and_exit(-1);
812 }
813 if (opts.ronly)
814 mount(NULL, "/", "bind", MS_REMOUNT | MS_BIND | MS_RDONLY, 0);
815
816 umask(old_umask);
817 post_jail_fs();
818 }
819
820 static int write_uid_gid_map(pid_t child_pid, bool gidmap, char *mapstr)
821 {
822 int map_file;
823 char map_path[64];
824
825 if (snprintf(map_path, sizeof(map_path), "/proc/%d/%s",
826 child_pid, gidmap?"gid_map":"uid_map") < 0)
827 return -1;
828
829 if ((map_file = open(map_path, O_WRONLY)) < 0)
830 return -1;
831
832 if (dprintf(map_file, "%s", mapstr)) {
833 close(map_file);
834 return -1;
835 }
836
837 close(map_file);
838 return 0;
839 }
840
841 static int write_single_uid_gid_map(pid_t child_pid, bool gidmap, int id)
842 {
843 int map_file;
844 char map_path[64];
845 const char *map_format = "%d %d %d\n";
846 if (snprintf(map_path, sizeof(map_path), "/proc/%d/%s",
847 child_pid, gidmap?"gid_map":"uid_map") < 0)
848 return -1;
849
850 if ((map_file = open(map_path, O_WRONLY)) < 0)
851 return -1;
852
853 if (dprintf(map_file, map_format, 0, id, 1) < 0) {
854 close(map_file);
855 return -1;
856 }
857
858 close(map_file);
859 return 0;
860 }
861
862 static int write_setgroups(pid_t child_pid, bool allow)
863 {
864 int setgroups_file;
865 char setgroups_path[64];
866
867 if (snprintf(setgroups_path, sizeof(setgroups_path), "/proc/%d/setgroups",
868 child_pid) < 0) {
869 return -1;
870 }
871
872 if ((setgroups_file = open(setgroups_path, O_WRONLY)) < 0) {
873 return -1;
874 }
875
876 if (dprintf(setgroups_file, "%s", allow?"allow":"deny") == -1) {
877 close(setgroups_file);
878 return -1;
879 }
880
881 close(setgroups_file);
882 return 0;
883 }
884
885 static void get_jail_user(int *user, int *user_gid, int *gr_gid)
886 {
887 struct passwd *p = NULL;
888 struct group *g = NULL;
889
890 if (opts.user) {
891 p = getpwnam(opts.user);
892 if (!p) {
893 ERROR("failed to get uid/gid for user %s: %d (%s)\n",
894 opts.user, errno, strerror(errno));
895 free_and_exit(EXIT_FAILURE);
896 }
897 *user = p->pw_uid;
898 *user_gid = p->pw_gid;
899 } else {
900 *user = -1;
901 *user_gid = -1;
902 }
903
904 if (opts.group) {
905 g = getgrnam(opts.group);
906 if (!g) {
907 ERROR("failed to get gid for group %s: %m\n", opts.group);
908 free_and_exit(EXIT_FAILURE);
909 }
910 *gr_gid = g->gr_gid;
911 } else {
912 *gr_gid = -1;
913 }
914 };
915
916 static void set_jail_user(int pw_uid, int user_gid, int gr_gid)
917 {
918 if (opts.user && (user_gid != -1) && initgroups(opts.user, user_gid)) {
919 ERROR("failed to initgroups() for user %s: %m\n", opts.user);
920 free_and_exit(EXIT_FAILURE);
921 }
922
923 if ((gr_gid != -1) && setregid(gr_gid, gr_gid)) {
924 ERROR("failed to set group id %d: %m\n", gr_gid);
925 free_and_exit(EXIT_FAILURE);
926 }
927
928 if ((pw_uid != -1) && setreuid(pw_uid, pw_uid)) {
929 ERROR("failed to set user id %d: %m\n", pw_uid);
930 free_and_exit(EXIT_FAILURE);
931 }
932 }
933
934 static int apply_rlimits(void)
935 {
936 int resource;
937
938 for (resource = 0; resource < RLIM_NLIMITS; ++resource) {
939 if (opts.rlimits[resource])
940 DEBUG("applying limits to resource %u\n", resource);
941
942 if (opts.rlimits[resource] &&
943 setrlimit(resource, opts.rlimits[resource]))
944 return errno;
945 }
946
947 return 0;
948 }
949
950 #define MAX_ENVP 64
951 static char** build_envp(const char *seccomp, char **ocienvp)
952 {
953 static char *envp[MAX_ENVP];
954 static char preload_var[PATH_MAX];
955 static char seccomp_var[PATH_MAX];
956 static char seccomp_debug_var[20];
957 static char debug_var[] = "LD_DEBUG=all";
958 static char container_var[] = "container=ujail";
959 const char *preload_lib = find_lib("libpreload-seccomp.so");
960 char **addenv;
961
962 int count = 0;
963
964 if (seccomp && !preload_lib) {
965 ERROR("failed to add preload-lib to env\n");
966 return NULL;
967 }
968 if (seccomp) {
969 snprintf(seccomp_var, sizeof(seccomp_var), "SECCOMP_FILE=%s", seccomp);
970 envp[count++] = seccomp_var;
971 snprintf(seccomp_debug_var, sizeof(seccomp_debug_var), "SECCOMP_DEBUG=%2d", debug);
972 envp[count++] = seccomp_debug_var;
973 snprintf(preload_var, sizeof(preload_var), "LD_PRELOAD=%s", preload_lib);
974 envp[count++] = preload_var;
975 }
976
977 envp[count++] = container_var;
978
979 if (debug > 1)
980 envp[count++] = debug_var;
981
982 addenv = ocienvp;
983 while (addenv && *addenv) {
984 envp[count++] = *(addenv++);
985 if (count >= MAX_ENVP) {
986 ERROR("environment limited to %d extra records, truncating\n", MAX_ENVP);
987 break;
988 }
989 }
990 return envp;
991 }
992
993 static void usage(void)
994 {
995 fprintf(stderr, "ujail <options> -- <binary> <params ...>\n");
996 fprintf(stderr, " -d <num>\tshow debug log (increase num to increase verbosity)\n");
997 fprintf(stderr, " -S <file>\tseccomp filter config\n");
998 fprintf(stderr, " -C <file>\tcapabilities drop config\n");
999 fprintf(stderr, " -c\t\tset PR_SET_NO_NEW_PRIVS\n");
1000 fprintf(stderr, " -n <name>\tthe name of the jail\n");
1001 fprintf(stderr, " -e <var>\timport environment variable\n");
1002 fprintf(stderr, "namespace jail options:\n");
1003 fprintf(stderr, " -h <hostname>\tchange the hostname of the jail\n");
1004 fprintf(stderr, " -N\t\tjail has network namespace\n");
1005 fprintf(stderr, " -f\t\tjail has user namespace\n");
1006 fprintf(stderr, " -F\t\tjail has cgroups namespace\n");
1007 fprintf(stderr, " -r <file>\treadonly files that should be staged\n");
1008 fprintf(stderr, " -w <file>\twriteable files that should be staged\n");
1009 fprintf(stderr, " -p\t\tjail has /proc\n");
1010 fprintf(stderr, " -s\t\tjail has /sys\n");
1011 fprintf(stderr, " -l\t\tjail has /dev/log\n");
1012 fprintf(stderr, " -u\t\tjail has a ubus socket\n");
1013 fprintf(stderr, " -U <name>\tuser to run jailed process\n");
1014 fprintf(stderr, " -G <name>\tgroup to run jailed process\n");
1015 fprintf(stderr, " -o\t\tremont jail root (/) read only\n");
1016 fprintf(stderr, " -R <dir>\texternal jail rootfs (system container)\n");
1017 fprintf(stderr, " -O <dir>\tdirectory for r/w overlayfs\n");
1018 fprintf(stderr, " -T <size>\tuse tmpfs r/w overlayfs with <size>\n");
1019 fprintf(stderr, " -E\t\tfail if jail cannot be setup\n");
1020 fprintf(stderr, " -y\t\tprovide jail console\n");
1021 fprintf(stderr, " -J <dir>\tcreate container from OCI bundle\n");
1022 fprintf(stderr, " -i\t\tstart container immediately\n");
1023 fprintf(stderr, " -P <pidfile>\tcreate <pidfile>\n");
1024 fprintf(stderr, "\nWarning: by default root inside the jail is the same\n\
1025 and he has the same powers as root outside the jail,\n\
1026 thus he can escape the jail and/or break stuff.\n\
1027 Please use seccomp/capabilities (-S/-C) to restrict his powers\n\n\
1028 If you use none of the namespace jail options,\n\
1029 ujail will not use namespace/build a jail,\n\
1030 and will only drop capabilities/apply seccomp filter.\n\n");
1031 }
1032
1033 static int* get_namespace_fd(const unsigned int nstype)
1034 {
1035 switch (nstype) {
1036 case CLONE_NEWPID:
1037 return &opts.setns.pid;
1038 case CLONE_NEWNET:
1039 return &opts.setns.net;
1040 case CLONE_NEWNS:
1041 return &opts.setns.ns;
1042 case CLONE_NEWIPC:
1043 return &opts.setns.ipc;
1044 case CLONE_NEWUTS:
1045 return &opts.setns.uts;
1046 case CLONE_NEWUSER:
1047 return &opts.setns.user;
1048 case CLONE_NEWCGROUP:
1049 return &opts.setns.cgroup;
1050 #ifdef CLONE_NEWTIME
1051 case CLONE_NEWTIME:
1052 return &opts.setns.time;
1053 #endif
1054 default:
1055 return NULL;
1056 }
1057 }
1058
1059 static int setns_open(unsigned long nstype)
1060 {
1061 int *fd = get_namespace_fd(nstype);
1062
1063 assert(fd != NULL);
1064
1065 if (*fd < 0)
1066 return 0;
1067
1068 if (setns(*fd, nstype) == -1) {
1069 close(*fd);
1070 return errno;
1071 }
1072
1073 close(*fd);
1074 return 0;
1075 }
1076
1077 static int jail_running = 0;
1078 static int jail_return_code = 0;
1079
1080 static void jail_process_timeout_cb(struct uloop_timeout *t);
1081 static struct uloop_timeout jail_process_timeout = {
1082 .cb = jail_process_timeout_cb,
1083 };
1084 static void poststop(void);
1085 static void jail_process_handler(struct uloop_process *c, int ret)
1086 {
1087 uloop_timeout_cancel(&jail_process_timeout);
1088 if (WIFEXITED(ret)) {
1089 jail_return_code = WEXITSTATUS(ret);
1090 INFO("jail (%d) exited with exit: %d\n", c->pid, jail_return_code);
1091 } else {
1092 jail_return_code = WTERMSIG(ret);
1093 INFO("jail (%d) exited with signal: %d\n", c->pid, jail_return_code);
1094 }
1095 jail_running = 0;
1096 poststop();
1097 }
1098
1099 static struct uloop_process jail_process = {
1100 .cb = jail_process_handler,
1101 };
1102
1103 static void jail_process_timeout_cb(struct uloop_timeout *t)
1104 {
1105 DEBUG("jail process failed to stop, sending SIGKILL\n");
1106 kill(jail_process.pid, SIGKILL);
1107 }
1108
1109 static void jail_handle_signal(int signo)
1110 {
1111 if (hook_running) {
1112 DEBUG("forwarding signal %d to the hook process\n", signo);
1113 kill(hook_process.pid, signo);
1114 /* set timeout to send SIGKILL hook process in case SIGTERM doesn't succeed */
1115 if (signo == SIGTERM)
1116 uloop_timeout_set(&hook_process_timeout, opts.term_timeout * 1000);
1117 }
1118
1119 if (jail_running) {
1120 DEBUG("forwarding signal %d to the jailed process\n", signo);
1121 kill(jail_process.pid, signo);
1122 /* set timeout to send SIGKILL jail process in case SIGTERM doesn't succeed */
1123 if (signo == SIGTERM)
1124 uloop_timeout_set(&jail_process_timeout, opts.term_timeout * 1000);
1125 }
1126 }
1127
1128 static void signals_init(void)
1129 {
1130 int i;
1131 sigset_t sigmask;
1132
1133 sigfillset(&sigmask);
1134 for (i = 0; i < _NSIG; i++) {
1135 struct sigaction s = { 0 };
1136
1137 if (!sigismember(&sigmask, i))
1138 continue;
1139 if ((i == SIGCHLD) || (i == SIGPIPE) || (i == SIGSEGV) || (i == SIGSTOP) || (i == SIGKILL))
1140 continue;
1141
1142 s.sa_handler = jail_handle_signal;
1143 sigaction(i, &s, NULL);
1144 }
1145 }
1146
1147 static void pre_exec_jail(struct uloop_timeout *t);
1148 static struct uloop_timeout pre_exec_timeout = {
1149 .cb = pre_exec_jail,
1150 };
1151
1152 int pipes[4];
1153 static int exec_jail(void *arg)
1154 {
1155 char buf[1];
1156
1157 exit_from_child = true;
1158 prctl(PR_SET_SECUREBITS, 0);
1159
1160 uloop_init();
1161 signals_init();
1162
1163 close(pipes[0]);
1164 close(pipes[3]);
1165
1166 setns_open(CLONE_NEWUSER);
1167 setns_open(CLONE_NEWNET);
1168 setns_open(CLONE_NEWNS);
1169 setns_open(CLONE_NEWIPC);
1170 setns_open(CLONE_NEWUTS);
1171
1172 buf[0] = 'i';
1173 if (write(pipes[1], buf, 1) < 1) {
1174 ERROR("can't write to parent\n");
1175 return EXIT_FAILURE;
1176 }
1177 close(pipes[1]);
1178 if (read(pipes[2], buf, 1) < 1) {
1179 ERROR("can't read from parent\n");
1180 return EXIT_FAILURE;
1181 }
1182 if (buf[0] != 'O') {
1183 ERROR("parent had an error, child exiting\n");
1184 return EXIT_FAILURE;
1185 }
1186
1187 if (opts.namespace & CLONE_NEWCGROUP)
1188 unshare(CLONE_NEWCGROUP);
1189
1190 setns_open(CLONE_NEWCGROUP);
1191
1192 if ((opts.namespace & CLONE_NEWUSER) || (opts.setns.user != -1)) {
1193 if (setregid(0, 0) < 0) {
1194 ERROR("setgid\n");
1195 free_and_exit(EXIT_FAILURE);
1196 }
1197 if (setreuid(0, 0) < 0) {
1198 ERROR("setuid\n");
1199 free_and_exit(EXIT_FAILURE);
1200 }
1201 if (setgroups(0, NULL) < 0) {
1202 ERROR("setgroups\n");
1203 free_and_exit(EXIT_FAILURE);
1204 }
1205 }
1206
1207 if (opts.namespace && opts.hostname && strlen(opts.hostname) > 0
1208 && sethostname(opts.hostname, strlen(opts.hostname))) {
1209 ERROR("sethostname(%s) failed: %m\n", opts.hostname);
1210 free_and_exit(EXIT_FAILURE);
1211 }
1212
1213 uloop_timeout_add(&pre_exec_timeout);
1214 uloop_run();
1215
1216 free_and_exit(-1);
1217 return -1;
1218 }
1219
1220 static void pre_exec_jail(struct uloop_timeout *t)
1221 {
1222 if ((opts.namespace & CLONE_NEWNS) && build_jail_fs()) {
1223 ERROR("failed to build jail fs\n");
1224 free_and_exit(EXIT_FAILURE);
1225 } else {
1226 run_hooks(opts.hooks.createContainer, post_jail_fs);
1227 }
1228 }
1229
1230 static void post_start_hook(void);
1231 static void post_jail_fs(void)
1232 {
1233 char buf[1];
1234
1235 if (read(pipes[2], buf, 1) < 1) {
1236 ERROR("can't read from parent\n");
1237 free_and_exit(EXIT_FAILURE);
1238 }
1239 if (buf[0] != '!') {
1240 ERROR("parent had an error, child exiting\n");
1241 free_and_exit(EXIT_FAILURE);
1242 }
1243 close(pipes[2]);
1244
1245 run_hooks(opts.hooks.startContainer, post_start_hook);
1246 }
1247
1248 static void post_start_hook(void)
1249 {
1250 int pw_uid, pw_gid, gr_gid;
1251
1252 /*
1253 * make sure setuid/setgid won't drop capabilities in case capabilities
1254 * have been specified explicitely.
1255 */
1256 if (opts.capset.apply) {
1257 if (prctl(PR_SET_SECUREBITS, SECBIT_NO_SETUID_FIXUP)) {
1258 ERROR("prctl(PR_SET_SECUREBITS) failed: %m\n");
1259 free_and_exit(EXIT_FAILURE);
1260 }
1261 }
1262
1263 /* drop capabilities, retain those still needed to further setup jail */
1264 if (applyOCIcapabilities(opts.capset, (1LLU << CAP_SETGID) | (1LLU << CAP_SETUID) | (1LLU << CAP_SETPCAP)))
1265 free_and_exit(EXIT_FAILURE);
1266
1267 /* use either cmdline-supplied user/group or uid/gid from OCI spec */
1268 get_jail_user(&pw_uid, &pw_gid, &gr_gid);
1269 set_jail_user(opts.pw_uid?:pw_uid, opts.pw_gid?:pw_gid, opts.gr_gid?:gr_gid);
1270
1271 if (opts.additional_gids &&
1272 (setgroups(opts.num_additional_gids, opts.additional_gids) < 0)) {
1273 ERROR("setgroups failed: %m\n");
1274 free_and_exit(EXIT_FAILURE);
1275 }
1276
1277 if (opts.set_umask)
1278 umask(opts.umask);
1279
1280 /* restore securebits back to normal (and lock them if not in userns) */
1281 if (opts.capset.apply) {
1282 if (prctl(PR_SET_SECUREBITS, (opts.namespace & CLONE_NEWUSER)?0:
1283 SECBIT_KEEP_CAPS_LOCKED|SECBIT_NO_SETUID_FIXUP_LOCKED|SECBIT_NOROOT_LOCKED)) {
1284 ERROR("prctl(PR_SET_SECUREBITS) failed: %m\n");
1285 free_and_exit(EXIT_FAILURE);
1286 }
1287 }
1288
1289 /* drop remaining capabilities to end up with specified sets */
1290 if (applyOCIcapabilities(opts.capset, 0))
1291 free_and_exit(EXIT_FAILURE);
1292
1293 if (opts.no_new_privs && prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
1294 ERROR("prctl(PR_SET_NO_NEW_PRIVS) failed: %m\n");
1295 free_and_exit(EXIT_FAILURE);
1296 }
1297
1298 char **envp = build_envp(opts.seccomp, opts.envp);
1299 if (!envp)
1300 free_and_exit(EXIT_FAILURE);
1301
1302 if (opts.cwd && chdir(opts.cwd))
1303 free_and_exit(EXIT_FAILURE);
1304
1305 if (opts.ociseccomp && applyOCIlinuxseccomp(opts.ociseccomp))
1306 free_and_exit(EXIT_FAILURE);
1307
1308 uloop_end();
1309 free_opts(false);
1310 INFO("exec-ing %s\n", *opts.jail_argv);
1311 if (opts.envp) /* respect PATH if potentially set in ENV */
1312 execvpe(*opts.jail_argv, opts.jail_argv, envp);
1313 else
1314 execve(*opts.jail_argv, opts.jail_argv, envp);
1315
1316 /* we get there only if execve fails */
1317 ERROR("failed to execve %s: %m\n", *opts.jail_argv);
1318 exit(EXIT_FAILURE);
1319 }
1320
1321 int ns_open_pid(const char *nstype, const pid_t target_ns)
1322 {
1323 char pid_pid_path[PATH_MAX];
1324
1325 snprintf(pid_pid_path, sizeof(pid_pid_path), "/proc/%u/ns/%s", target_ns, nstype);
1326
1327 return open(pid_pid_path, O_RDONLY);
1328 }
1329
1330 static int parseOCIenvarray(struct blob_attr *msg, char ***envp)
1331 {
1332 struct blob_attr *cur;
1333 int sz = 0, rem;
1334
1335 blobmsg_for_each_attr(cur, msg, rem)
1336 ++sz;
1337
1338 if (sz > 0) {
1339 *envp = calloc(1 + sz, sizeof(char*));
1340 if (!(*envp))
1341 return ENOMEM;
1342 } else {
1343 *envp = NULL;
1344 return 0;
1345 }
1346
1347 sz = 0;
1348 blobmsg_for_each_attr(cur, msg, rem)
1349 (*envp)[sz++] = strdup(blobmsg_get_string(cur));
1350
1351 if (sz)
1352 (*envp)[sz] = NULL;
1353
1354 return 0;
1355 }
1356
1357 enum {
1358 OCI_ROOT_PATH,
1359 OCI_ROOT_READONLY,
1360 __OCI_ROOT_MAX,
1361 };
1362
1363 static const struct blobmsg_policy oci_root_policy[] = {
1364 [OCI_ROOT_PATH] = { "path", BLOBMSG_TYPE_STRING },
1365 [OCI_ROOT_READONLY] = { "readonly", BLOBMSG_TYPE_BOOL },
1366 };
1367
1368 static int parseOCIroot(const char *jsonfile, struct blob_attr *msg)
1369 {
1370 char extroot[PATH_MAX] = { 0 };
1371 struct blob_attr *tb[__OCI_ROOT_MAX];
1372 char *cur;
1373 char *root_path;
1374
1375 blobmsg_parse(oci_root_policy, __OCI_ROOT_MAX, tb, blobmsg_data(msg), blobmsg_len(msg));
1376
1377 if (!tb[OCI_ROOT_PATH])
1378 return ENODATA;
1379
1380 root_path = blobmsg_get_string(tb[OCI_ROOT_PATH]);
1381
1382 /* prepend bundle directory in case of relative paths */
1383 if (root_path[0] != '/') {
1384 strncpy(extroot, jsonfile, PATH_MAX - 1);
1385
1386 cur = strrchr(extroot, '/');
1387
1388 if (!cur)
1389 return ENOTDIR;
1390
1391 *(++cur) = '\0';
1392 }
1393
1394 strncat(extroot, root_path, PATH_MAX - (strlen(extroot) + 1));
1395
1396 /* follow symbolic link(s) */
1397 opts.extroot = realpath(extroot, NULL);
1398 if (!opts.extroot)
1399 return errno;
1400
1401 if (tb[OCI_ROOT_READONLY])
1402 opts.ronly = blobmsg_get_bool(tb[OCI_ROOT_READONLY]);
1403
1404 return 0;
1405 }
1406
1407
1408 enum {
1409 OCI_HOOK_PATH,
1410 OCI_HOOK_ARGS,
1411 OCI_HOOK_ENV,
1412 OCI_HOOK_TIMEOUT,
1413 __OCI_HOOK_MAX,
1414 };
1415
1416 static const struct blobmsg_policy oci_hook_policy[] = {
1417 [OCI_HOOK_PATH] = { "path", BLOBMSG_TYPE_STRING },
1418 [OCI_HOOK_ARGS] = { "args", BLOBMSG_TYPE_ARRAY },
1419 [OCI_HOOK_ENV] = { "env", BLOBMSG_TYPE_ARRAY },
1420 [OCI_HOOK_TIMEOUT] = { "timeout", BLOBMSG_TYPE_INT32 },
1421 };
1422
1423
1424 static int parseOCIhook(struct hook_execvpe ***hooklist, struct blob_attr *msg)
1425 {
1426 struct blob_attr *tb[__OCI_HOOK_MAX];
1427 struct blob_attr *cur;
1428 int rem, ret = 0;
1429 int idx = 0;
1430
1431 blobmsg_for_each_attr(cur, msg, rem)
1432 ++idx;
1433
1434 if (!idx)
1435 return 0;
1436
1437 *hooklist = calloc(idx + 1, sizeof(struct hook_execvpe *));
1438 idx = 0;
1439
1440 if (!(*hooklist))
1441 return ENOMEM;
1442
1443 blobmsg_for_each_attr(cur, msg, rem) {
1444 blobmsg_parse(oci_hook_policy, __OCI_HOOK_MAX, tb, blobmsg_data(cur), blobmsg_len(cur));
1445
1446 if (!tb[OCI_HOOK_PATH]) {
1447 ret = EINVAL;
1448 goto errout;
1449 }
1450
1451 (*hooklist)[idx] = calloc(1, sizeof(struct hook_execvpe));
1452 if (tb[OCI_HOOK_ARGS]) {
1453 ret = parseOCIenvarray(tb[OCI_HOOK_ARGS], &((*hooklist)[idx]->argv));
1454 if (ret)
1455 goto errout;
1456 } else {
1457 (*hooklist)[idx]->argv = calloc(2, sizeof(char *));
1458 ((*hooklist)[idx]->argv)[0] = strdup(blobmsg_get_string(tb[OCI_HOOK_PATH]));
1459 ((*hooklist)[idx]->argv)[1] = NULL;
1460 };
1461
1462
1463 if (tb[OCI_HOOK_ENV]) {
1464 ret = parseOCIenvarray(tb[OCI_HOOK_ENV], &((*hooklist)[idx]->envp));
1465 if (ret)
1466 goto errout;
1467 }
1468
1469 if (tb[OCI_HOOK_TIMEOUT])
1470 (*hooklist)[idx]->timeout = blobmsg_get_u32(tb[OCI_HOOK_TIMEOUT]);
1471
1472 (*hooklist)[idx]->file = strdup(blobmsg_get_string(tb[OCI_HOOK_PATH]));
1473
1474 ++idx;
1475 }
1476
1477 (*hooklist)[idx] = NULL;
1478
1479 DEBUG("added %d hooks\n", idx);
1480
1481 return 0;
1482
1483 errout:
1484 free_hooklist(*hooklist);
1485 *hooklist = NULL;
1486
1487 return ret;
1488 };
1489
1490
1491 enum {
1492 OCI_HOOKS_PRESTART,
1493 OCI_HOOKS_CREATERUNTIME,
1494 OCI_HOOKS_CREATECONTAINER,
1495 OCI_HOOKS_STARTCONTAINER,
1496 OCI_HOOKS_POSTSTART,
1497 OCI_HOOKS_POSTSTOP,
1498 __OCI_HOOKS_MAX,
1499 };
1500
1501 static const struct blobmsg_policy oci_hooks_policy[] = {
1502 [OCI_HOOKS_PRESTART] = { "prestart", BLOBMSG_TYPE_ARRAY },
1503 [OCI_HOOKS_CREATERUNTIME] = { "createRuntime", BLOBMSG_TYPE_ARRAY },
1504 [OCI_HOOKS_CREATECONTAINER] = { "createContainer", BLOBMSG_TYPE_ARRAY },
1505 [OCI_HOOKS_STARTCONTAINER] = { "startContainer", BLOBMSG_TYPE_ARRAY },
1506 [OCI_HOOKS_POSTSTART] = { "poststart", BLOBMSG_TYPE_ARRAY },
1507 [OCI_HOOKS_POSTSTOP] = { "poststop", BLOBMSG_TYPE_ARRAY },
1508 };
1509
1510 static int parseOCIhooks(struct blob_attr *msg)
1511 {
1512 struct blob_attr *tb[__OCI_HOOKS_MAX];
1513 int ret;
1514
1515 blobmsg_parse(oci_hooks_policy, __OCI_HOOKS_MAX, tb, blobmsg_data(msg), blobmsg_len(msg));
1516
1517 if (tb[OCI_HOOKS_PRESTART])
1518 INFO("warning: ignoring deprecated prestart hook\n");
1519
1520 if (tb[OCI_HOOKS_CREATERUNTIME]) {
1521 ret = parseOCIhook(&opts.hooks.createRuntime, tb[OCI_HOOKS_CREATERUNTIME]);
1522 if (ret)
1523 return ret;
1524 }
1525
1526 if (tb[OCI_HOOKS_CREATECONTAINER]) {
1527 ret = parseOCIhook(&opts.hooks.createContainer, tb[OCI_HOOKS_CREATECONTAINER]);
1528 if (ret)
1529 goto out_createruntime;
1530 }
1531
1532 if (tb[OCI_HOOKS_STARTCONTAINER]) {
1533 ret = parseOCIhook(&opts.hooks.startContainer, tb[OCI_HOOKS_STARTCONTAINER]);
1534 if (ret)
1535 goto out_createcontainer;
1536 }
1537
1538 if (tb[OCI_HOOKS_POSTSTART]) {
1539 ret = parseOCIhook(&opts.hooks.poststart, tb[OCI_HOOKS_POSTSTART]);
1540 if (ret)
1541 goto out_startcontainer;
1542 }
1543
1544 if (tb[OCI_HOOKS_POSTSTOP]) {
1545 ret = parseOCIhook(&opts.hooks.poststop, tb[OCI_HOOKS_POSTSTOP]);
1546 if (ret)
1547 goto out_poststart;
1548 }
1549
1550 return 0;
1551
1552 out_poststart:
1553 free_hooklist(opts.hooks.poststart);
1554 out_startcontainer:
1555 free_hooklist(opts.hooks.startContainer);
1556 out_createcontainer:
1557 free_hooklist(opts.hooks.createContainer);
1558 out_createruntime:
1559 free_hooklist(opts.hooks.createRuntime);
1560
1561 return ret;
1562 };
1563
1564
1565 enum {
1566 OCI_PROCESS_USER_UID,
1567 OCI_PROCESS_USER_GID,
1568 OCI_PROCESS_USER_UMASK,
1569 OCI_PROCESS_USER_ADDITIONALGIDS,
1570 __OCI_PROCESS_USER_MAX,
1571 };
1572
1573 static const struct blobmsg_policy oci_process_user_policy[] = {
1574 [OCI_PROCESS_USER_UID] = { "uid", BLOBMSG_TYPE_INT32 },
1575 [OCI_PROCESS_USER_GID] = { "gid", BLOBMSG_TYPE_INT32 },
1576 [OCI_PROCESS_USER_UMASK] = { "umask", BLOBMSG_TYPE_INT32 },
1577 [OCI_PROCESS_USER_ADDITIONALGIDS] = { "additionalGids", BLOBMSG_TYPE_ARRAY },
1578 };
1579
1580 static int parseOCIprocessuser(struct blob_attr *msg) {
1581 struct blob_attr *tb[__OCI_PROCESS_USER_MAX];
1582 struct blob_attr *cur;
1583 int rem;
1584 int has_gid = 0;
1585
1586 blobmsg_parse(oci_process_user_policy, __OCI_PROCESS_USER_MAX, tb, blobmsg_data(msg), blobmsg_len(msg));
1587
1588 if (tb[OCI_PROCESS_USER_UID])
1589 opts.pw_uid = blobmsg_get_u32(tb[OCI_PROCESS_USER_UID]);
1590
1591 if (tb[OCI_PROCESS_USER_GID]) {
1592 opts.pw_gid = blobmsg_get_u32(tb[OCI_PROCESS_USER_GID]);
1593 opts.gr_gid = blobmsg_get_u32(tb[OCI_PROCESS_USER_GID]);
1594 has_gid = 1;
1595 }
1596
1597 if (tb[OCI_PROCESS_USER_ADDITIONALGIDS]) {
1598 size_t gidcnt = 0;
1599
1600 blobmsg_for_each_attr(cur, tb[OCI_PROCESS_USER_ADDITIONALGIDS], rem) {
1601 ++gidcnt;
1602 if (has_gid && (blobmsg_get_u32(cur) == opts.gr_gid))
1603 continue;
1604 }
1605
1606 if (gidcnt) {
1607 opts.additional_gids = calloc(gidcnt + has_gid, sizeof(gid_t));
1608 gidcnt = 0;
1609
1610 /* always add primary GID to set of GIDs if set */
1611 if (has_gid)
1612 opts.additional_gids[gidcnt++] = opts.gr_gid;
1613
1614 blobmsg_for_each_attr(cur, tb[OCI_PROCESS_USER_ADDITIONALGIDS], rem) {
1615 if (has_gid && (blobmsg_get_u32(cur) == opts.gr_gid))
1616 continue;
1617 opts.additional_gids[gidcnt++] = blobmsg_get_u32(cur);
1618 }
1619 opts.num_additional_gids = gidcnt;
1620 }
1621 DEBUG("read %zu additional groups\n", gidcnt);
1622 }
1623
1624 if (tb[OCI_PROCESS_USER_UMASK]) {
1625 opts.umask = blobmsg_get_u32(tb[OCI_PROCESS_USER_UMASK]);
1626 opts.set_umask = true;
1627 }
1628
1629 return 0;
1630 }
1631
1632 enum {
1633 OCI_PROCESS_RLIMIT_TYPE,
1634 OCI_PROCESS_RLIMIT_SOFT,
1635 OCI_PROCESS_RLIMIT_HARD,
1636 __OCI_PROCESS_RLIMIT_MAX,
1637 };
1638
1639 static const struct blobmsg_policy oci_process_rlimit_policy[] = {
1640 [OCI_PROCESS_RLIMIT_TYPE] = { "type", BLOBMSG_TYPE_STRING },
1641 [OCI_PROCESS_RLIMIT_SOFT] = { "soft", BLOBMSG_CAST_INT64 },
1642 [OCI_PROCESS_RLIMIT_HARD] = { "hard", BLOBMSG_CAST_INT64 },
1643 };
1644
1645 /* from manpage GETRLIMIT(2) */
1646 static const char* const rlimit_names[RLIM_NLIMITS] = {
1647 [RLIMIT_AS] = "AS",
1648 [RLIMIT_CORE] = "CORE",
1649 [RLIMIT_CPU] = "CPU",
1650 [RLIMIT_DATA] = "DATA",
1651 [RLIMIT_FSIZE] = "FSIZE",
1652 [RLIMIT_LOCKS] = "LOCKS",
1653 [RLIMIT_MEMLOCK] = "MEMLOCK",
1654 [RLIMIT_MSGQUEUE] = "MSGQUEUE",
1655 [RLIMIT_NICE] = "NICE",
1656 [RLIMIT_NOFILE] = "NOFILE",
1657 [RLIMIT_NPROC] = "NPROC",
1658 [RLIMIT_RSS] = "RSS",
1659 [RLIMIT_RTPRIO] = "RTPRIO",
1660 [RLIMIT_RTTIME] = "RTTIME",
1661 [RLIMIT_SIGPENDING] = "SIGPENDING",
1662 [RLIMIT_STACK] = "STACK",
1663 };
1664
1665 static int resolve_rlimit(char *type) {
1666 unsigned int rltype;
1667
1668 for (rltype = 0; rltype < RLIM_NLIMITS; ++rltype)
1669 if (rlimit_names[rltype] &&
1670 !strncmp("RLIMIT_", type, 7) &&
1671 !strcmp(rlimit_names[rltype], type + 7))
1672 return rltype;
1673
1674 return -1;
1675 }
1676
1677
1678 static int parseOCIrlimit(struct blob_attr *msg)
1679 {
1680 struct blob_attr *tb[__OCI_PROCESS_RLIMIT_MAX];
1681 int limtype = -1;
1682 struct rlimit *curlim;
1683
1684 blobmsg_parse(oci_process_rlimit_policy, __OCI_PROCESS_RLIMIT_MAX, tb, blobmsg_data(msg), blobmsg_len(msg));
1685
1686 if (!tb[OCI_PROCESS_RLIMIT_TYPE] ||
1687 !tb[OCI_PROCESS_RLIMIT_SOFT] ||
1688 !tb[OCI_PROCESS_RLIMIT_HARD])
1689 return ENODATA;
1690
1691 limtype = resolve_rlimit(blobmsg_get_string(tb[OCI_PROCESS_RLIMIT_TYPE]));
1692
1693 if (limtype < 0)
1694 return EINVAL;
1695
1696 if (opts.rlimits[limtype])
1697 return ENOTUNIQ;
1698
1699 curlim = malloc(sizeof(struct rlimit));
1700 curlim->rlim_cur = blobmsg_cast_u64(tb[OCI_PROCESS_RLIMIT_SOFT]);
1701 curlim->rlim_max = blobmsg_cast_u64(tb[OCI_PROCESS_RLIMIT_HARD]);
1702
1703 opts.rlimits[limtype] = curlim;
1704
1705 return 0;
1706 };
1707
1708 enum {
1709 OCI_PROCESS_ARGS,
1710 OCI_PROCESS_CAPABILITIES,
1711 OCI_PROCESS_CWD,
1712 OCI_PROCESS_ENV,
1713 OCI_PROCESS_OOMSCOREADJ,
1714 OCI_PROCESS_NONEWPRIVILEGES,
1715 OCI_PROCESS_RLIMITS,
1716 OCI_PROCESS_TERMINAL,
1717 OCI_PROCESS_USER,
1718 __OCI_PROCESS_MAX,
1719 };
1720
1721 static const struct blobmsg_policy oci_process_policy[] = {
1722 [OCI_PROCESS_ARGS] = { "args", BLOBMSG_TYPE_ARRAY },
1723 [OCI_PROCESS_CAPABILITIES] = { "capabilities", BLOBMSG_TYPE_TABLE },
1724 [OCI_PROCESS_CWD] = { "cwd", BLOBMSG_TYPE_STRING },
1725 [OCI_PROCESS_ENV] = { "env", BLOBMSG_TYPE_ARRAY },
1726 [OCI_PROCESS_OOMSCOREADJ] = { "oomScoreAdj", BLOBMSG_TYPE_INT32 },
1727 [OCI_PROCESS_NONEWPRIVILEGES] = { "noNewPrivileges", BLOBMSG_TYPE_BOOL },
1728 [OCI_PROCESS_RLIMITS] = { "rlimits", BLOBMSG_TYPE_ARRAY },
1729 [OCI_PROCESS_TERMINAL] = { "terminal", BLOBMSG_TYPE_BOOL },
1730 [OCI_PROCESS_USER] = { "user", BLOBMSG_TYPE_TABLE },
1731 };
1732
1733
1734 static int parseOCIprocess(struct blob_attr *msg)
1735 {
1736 struct blob_attr *tb[__OCI_PROCESS_MAX], *cur;
1737 int rem, res;
1738
1739 blobmsg_parse(oci_process_policy, __OCI_PROCESS_MAX, tb, blobmsg_data(msg), blobmsg_len(msg));
1740
1741 if (!tb[OCI_PROCESS_ARGS])
1742 return ENOENT;
1743
1744 res = parseOCIenvarray(tb[OCI_PROCESS_ARGS], &opts.jail_argv);
1745 if (res)
1746 return res;
1747
1748 if (tb[OCI_PROCESS_TERMINAL])
1749 opts.console = blobmsg_get_bool(tb[OCI_PROCESS_TERMINAL]);
1750
1751 if (tb[OCI_PROCESS_NONEWPRIVILEGES])
1752 opts.no_new_privs = blobmsg_get_bool(tb[OCI_PROCESS_NONEWPRIVILEGES]);
1753
1754 if (tb[OCI_PROCESS_CWD])
1755 opts.cwd = strdup(blobmsg_get_string(tb[OCI_PROCESS_CWD]));
1756
1757 if (tb[OCI_PROCESS_ENV]) {
1758 res = parseOCIenvarray(tb[OCI_PROCESS_ENV], &opts.envp);
1759 if (res)
1760 return res;
1761 }
1762
1763 if (tb[OCI_PROCESS_USER] && (res = parseOCIprocessuser(tb[OCI_PROCESS_USER])))
1764 return res;
1765
1766 if (tb[OCI_PROCESS_CAPABILITIES] &&
1767 (res = parseOCIcapabilities(&opts.capset, tb[OCI_PROCESS_CAPABILITIES])))
1768 return res;
1769
1770 if (tb[OCI_PROCESS_RLIMITS]) {
1771 blobmsg_for_each_attr(cur, tb[OCI_PROCESS_RLIMITS], rem) {
1772 res = parseOCIrlimit(cur);
1773 if (res)
1774 return res;
1775 }
1776 }
1777
1778 if (tb[OCI_PROCESS_OOMSCOREADJ]) {
1779 opts.oom_score_adj = blobmsg_get_u32(tb[OCI_PROCESS_OOMSCOREADJ]);
1780 opts.set_oom_score_adj = true;
1781 }
1782
1783 return 0;
1784 }
1785
1786 enum {
1787 OCI_LINUX_NAMESPACE_TYPE,
1788 OCI_LINUX_NAMESPACE_PATH,
1789 __OCI_LINUX_NAMESPACE_MAX,
1790 };
1791
1792 static const struct blobmsg_policy oci_linux_namespace_policy[] = {
1793 [OCI_LINUX_NAMESPACE_TYPE] = { "type", BLOBMSG_TYPE_STRING },
1794 [OCI_LINUX_NAMESPACE_PATH] = { "path", BLOBMSG_TYPE_STRING },
1795 };
1796
1797 static int resolve_nstype(char *type) {
1798 if (!strcmp("pid", type))
1799 return CLONE_NEWPID;
1800 else if (!strcmp("network", type))
1801 return CLONE_NEWNET;
1802 else if (!strcmp("net", type))
1803 return CLONE_NEWNET;
1804 else if (!strcmp("mount", type))
1805 return CLONE_NEWNS;
1806 else if (!strcmp("ipc", type))
1807 return CLONE_NEWIPC;
1808 else if (!strcmp("uts", type))
1809 return CLONE_NEWUTS;
1810 else if (!strcmp("user", type))
1811 return CLONE_NEWUSER;
1812 else if (!strcmp("cgroup", type))
1813 return CLONE_NEWCGROUP;
1814 #ifdef CLONE_NEWTIME
1815 else if (!strcmp("time", type))
1816 return CLONE_NEWTIME;
1817 #endif
1818 else
1819 return 0;
1820 }
1821
1822 static int parseOCIlinuxns(struct blob_attr *msg)
1823 {
1824 struct blob_attr *tb[__OCI_LINUX_NAMESPACE_MAX];
1825 int nstype;
1826 int *setns;
1827 int fd;
1828
1829 blobmsg_parse(oci_linux_namespace_policy, __OCI_LINUX_NAMESPACE_MAX, tb, blobmsg_data(msg), blobmsg_len(msg));
1830
1831 if (!tb[OCI_LINUX_NAMESPACE_TYPE])
1832 return EINVAL;
1833
1834 nstype = resolve_nstype(blobmsg_get_string(tb[OCI_LINUX_NAMESPACE_TYPE]));
1835 if (!nstype)
1836 return EINVAL;
1837
1838 if (opts.namespace & nstype)
1839 return ENOTUNIQ;
1840
1841 setns = get_namespace_fd(nstype);
1842
1843 if (!setns)
1844 return EFAULT;
1845
1846 if (*setns != -1)
1847 return ENOTUNIQ;
1848
1849 if (tb[OCI_LINUX_NAMESPACE_PATH]) {
1850 DEBUG("opening existing %s namespace from path %s\n",
1851 blobmsg_get_string(tb[OCI_LINUX_NAMESPACE_TYPE]),
1852 blobmsg_get_string(tb[OCI_LINUX_NAMESPACE_PATH]));
1853
1854 fd = open(blobmsg_get_string(tb[OCI_LINUX_NAMESPACE_PATH]), O_RDONLY);
1855 if (fd < 0)
1856 return errno?:ESTALE;
1857
1858 if (ioctl(fd, NS_GET_NSTYPE) != nstype) {
1859 close(fd);
1860 return EINVAL;
1861 }
1862
1863 DEBUG("opened existing %s namespace got filehandler %u\n",
1864 blobmsg_get_string(tb[OCI_LINUX_NAMESPACE_TYPE]),
1865 fd);
1866
1867 *setns = fd;
1868 } else {
1869 opts.namespace |= nstype;
1870 }
1871
1872 return 0;
1873 }
1874
1875 /*
1876 * join namespace of existing PID
1877 * The string argument is the reference PID followed by ':' and a
1878 * ',' separated list of namespaces to to join.
1879 */
1880 static int jail_join_ns(char *arg)
1881 {
1882 pid_t pid;
1883 int fd;
1884 int nstype;
1885 char *tmp, *etmp, *nspath;
1886 int *setns;
1887
1888 tmp = strchr(arg, ':');
1889 if (!tmp)
1890 return EINVAL;
1891
1892 *tmp = '\0';
1893 pid = atoi(arg);
1894
1895 do {
1896 ++tmp;
1897 etmp = strchr(tmp, ',');
1898 if (etmp)
1899 *etmp = '\0';
1900
1901 nstype = resolve_nstype(tmp);
1902 if (!nstype)
1903 return EINVAL;
1904
1905 if (opts.namespace & nstype)
1906 return ENOTUNIQ;
1907
1908 setns = get_namespace_fd(nstype);
1909
1910 if (!setns)
1911 return EFAULT;
1912
1913 if (*setns != -1)
1914 return ENOTUNIQ;
1915
1916 if (asprintf(&nspath, "/proc/%d/ns/%s", pid, tmp) < 0)
1917 return ENOMEM;
1918
1919 fd = open(nspath, O_RDONLY);
1920 free(nspath);
1921
1922 if (fd < 0)
1923 return errno?:ESTALE;
1924
1925 *setns = fd;
1926
1927 if (etmp)
1928 tmp = etmp;
1929 else
1930 tmp = NULL;
1931 } while (tmp);
1932
1933 return 0;
1934 }
1935
1936 static void get_jail_root_user(bool is_gidmap, uint32_t container_id, uint32_t host_id, uint32_t size)
1937 {
1938 if (container_id == 0 && size >= 1)
1939 if (!is_gidmap)
1940 opts.root_map_uid = host_id;
1941 }
1942
1943 enum {
1944 OCI_LINUX_UIDGIDMAP_CONTAINERID,
1945 OCI_LINUX_UIDGIDMAP_HOSTID,
1946 OCI_LINUX_UIDGIDMAP_SIZE,
1947 __OCI_LINUX_UIDGIDMAP_MAX,
1948 };
1949
1950 static const struct blobmsg_policy oci_linux_uidgidmap_policy[] = {
1951 [OCI_LINUX_UIDGIDMAP_CONTAINERID] = { "containerID", BLOBMSG_TYPE_INT32 },
1952 [OCI_LINUX_UIDGIDMAP_HOSTID] = { "hostID", BLOBMSG_TYPE_INT32 },
1953 [OCI_LINUX_UIDGIDMAP_SIZE] = { "size", BLOBMSG_TYPE_INT32 },
1954 };
1955
1956 static int parseOCIuidgidmappings(struct blob_attr *msg, bool is_gidmap)
1957 {
1958 struct blob_attr *tb[__OCI_LINUX_UIDGIDMAP_MAX];
1959 struct blob_attr *cur;
1960 int rem;
1961 char *map;
1962 size_t len, pos, totallen = 0;
1963
1964 blobmsg_for_each_attr(cur, msg, rem) {
1965 blobmsg_parse(oci_linux_uidgidmap_policy, __OCI_LINUX_UIDGIDMAP_MAX, tb, blobmsg_data(cur), blobmsg_len(cur));
1966
1967 if (!tb[OCI_LINUX_UIDGIDMAP_CONTAINERID] ||
1968 !tb[OCI_LINUX_UIDGIDMAP_HOSTID] ||
1969 !tb[OCI_LINUX_UIDGIDMAP_SIZE])
1970 return EINVAL;
1971
1972 /* count length */
1973 totallen += snprintf(NULL, 0, "%d %d %d\n",
1974 blobmsg_get_u32(tb[OCI_LINUX_UIDGIDMAP_CONTAINERID]),
1975 blobmsg_get_u32(tb[OCI_LINUX_UIDGIDMAP_HOSTID]),
1976 blobmsg_get_u32(tb[OCI_LINUX_UIDGIDMAP_SIZE]));
1977 }
1978
1979 /* allocate combined mapping string */
1980 map = malloc(totallen + 1);
1981 if (!map)
1982 return ENOMEM;
1983
1984 pos = 0;
1985 blobmsg_for_each_attr(cur, msg, rem) {
1986 blobmsg_parse(oci_linux_uidgidmap_policy, __OCI_LINUX_UIDGIDMAP_MAX, tb, blobmsg_data(cur), blobmsg_len(cur));
1987
1988 get_jail_root_user(is_gidmap, blobmsg_get_u32(tb[OCI_LINUX_UIDGIDMAP_CONTAINERID]),
1989 blobmsg_get_u32(tb[OCI_LINUX_UIDGIDMAP_HOSTID]),
1990 blobmsg_get_u32(tb[OCI_LINUX_UIDGIDMAP_SIZE]));
1991
1992 /* write mapping line into pre-allocated string */
1993 len = snprintf(&map[pos], totallen + 1, "%d %d %d\n",
1994 blobmsg_get_u32(tb[OCI_LINUX_UIDGIDMAP_CONTAINERID]),
1995 blobmsg_get_u32(tb[OCI_LINUX_UIDGIDMAP_HOSTID]),
1996 blobmsg_get_u32(tb[OCI_LINUX_UIDGIDMAP_SIZE]));
1997 pos += len;
1998 totallen -= len;
1999 }
2000
2001 assert(totallen == 0);
2002
2003 if (is_gidmap)
2004 opts.gidmap = map;
2005 else
2006 opts.uidmap = map;
2007
2008 return 0;
2009 }
2010
2011 enum {
2012 OCI_DEVICES_TYPE,
2013 OCI_DEVICES_PATH,
2014 OCI_DEVICES_MAJOR,
2015 OCI_DEVICES_MINOR,
2016 OCI_DEVICES_FILEMODE,
2017 OCI_DEVICES_UID,
2018 OCI_DEVICES_GID,
2019 __OCI_DEVICES_MAX,
2020 };
2021
2022 static const struct blobmsg_policy oci_devices_policy[] = {
2023 [OCI_DEVICES_TYPE] = { "type", BLOBMSG_TYPE_STRING },
2024 [OCI_DEVICES_PATH] = { "path", BLOBMSG_TYPE_STRING },
2025 [OCI_DEVICES_MAJOR] = { "major", BLOBMSG_TYPE_INT32 },
2026 [OCI_DEVICES_MINOR] = { "minor", BLOBMSG_TYPE_INT32 },
2027 [OCI_DEVICES_FILEMODE] = { "fileMode", BLOBMSG_TYPE_INT32 },
2028 [OCI_DEVICES_UID] = { "uid", BLOBMSG_TYPE_INT32 },
2029 [OCI_DEVICES_GID] = { "uid", BLOBMSG_TYPE_INT32 },
2030 };
2031
2032 static mode_t resolve_devtype(char *tstr)
2033 {
2034 if (!strcmp("c", tstr) ||
2035 !strcmp("u", tstr))
2036 return S_IFCHR;
2037 else if (!strcmp("b", tstr))
2038 return S_IFBLK;
2039 else if (!strcmp("p", tstr))
2040 return S_IFIFO;
2041 else
2042 return 0;
2043 }
2044
2045 static int parseOCIdevices(struct blob_attr *msg)
2046 {
2047 struct blob_attr *tb[__OCI_DEVICES_MAX];
2048 struct blob_attr *cur;
2049 int rem;
2050 size_t cnt = 0;
2051 struct mknod_args *tmp;
2052
2053 blobmsg_for_each_attr(cur, msg, rem)
2054 ++cnt;
2055
2056 opts.devices = calloc(cnt + 1, sizeof(struct mknod_args *));
2057
2058 cnt = 0;
2059 blobmsg_for_each_attr(cur, msg, rem) {
2060 blobmsg_parse(oci_devices_policy, __OCI_DEVICES_MAX, tb, blobmsg_data(cur), blobmsg_len(cur));
2061 if (!tb[OCI_DEVICES_TYPE] ||
2062 !tb[OCI_DEVICES_PATH])
2063 return ENODATA;
2064
2065 tmp = calloc(1, sizeof(struct mknod_args));
2066 if (!tmp)
2067 return ENOMEM;
2068
2069 tmp->mode = resolve_devtype(blobmsg_get_string(tb[OCI_DEVICES_TYPE]));
2070 if (!tmp->mode) {
2071 free(tmp);
2072 return EINVAL;
2073 }
2074
2075 if (tmp->mode != S_IFIFO) {
2076 if (!tb[OCI_DEVICES_MAJOR] || !tb[OCI_DEVICES_MINOR]) {
2077 free(tmp);
2078 return ENODATA;
2079 }
2080
2081 tmp->dev = makedev(blobmsg_get_u32(tb[OCI_DEVICES_MAJOR]),
2082 blobmsg_get_u32(tb[OCI_DEVICES_MINOR]));
2083 }
2084
2085 if (tb[OCI_DEVICES_FILEMODE]) {
2086 if (~(S_IRWXU|S_IRWXG|S_IRWXO) & blobmsg_get_u32(tb[OCI_DEVICES_FILEMODE])) {
2087 free(tmp);
2088 return EINVAL;
2089 }
2090
2091 tmp->mode |= blobmsg_get_u32(tb[OCI_DEVICES_FILEMODE]);
2092 } else {
2093 tmp->mode |= (S_IRUSR|S_IWUSR); /* 0600 */
2094 }
2095
2096 tmp->path = strdup(blobmsg_get_string(tb[OCI_DEVICES_PATH]));
2097
2098 if (tb[OCI_DEVICES_UID])
2099 tmp->uid = blobmsg_get_u32(tb[OCI_DEVICES_UID]);
2100 else
2101 tmp->uid = -1;
2102
2103 if (tb[OCI_DEVICES_GID])
2104 tmp->gid = blobmsg_get_u32(tb[OCI_DEVICES_GID]);
2105 else
2106 tmp->gid = -1;
2107
2108 DEBUG("read device %s (%s)\n", blobmsg_get_string(tb[OCI_DEVICES_PATH]), blobmsg_get_string(tb[OCI_DEVICES_TYPE]));
2109 opts.devices[cnt++] = tmp;
2110 }
2111
2112 opts.devices[cnt] = NULL;
2113
2114 return 0;
2115 }
2116
2117 static int parseOCIsysctl(struct blob_attr *msg)
2118 {
2119 struct blob_attr *cur;
2120 int rem;
2121 char *tmp, *tc;
2122 size_t cnt = 0;
2123
2124 blobmsg_for_each_attr(cur, msg, rem) {
2125 if (!blobmsg_name(cur) || !blobmsg_get_string(cur))
2126 return EINVAL;
2127
2128 ++cnt;
2129 }
2130
2131 if (!cnt)
2132 return 0;
2133
2134 opts.sysctl = calloc(cnt + 1, sizeof(struct sysctl_val *));
2135 if (!opts.sysctl)
2136 return ENOMEM;
2137
2138 cnt = 0;
2139 blobmsg_for_each_attr(cur, msg, rem) {
2140 opts.sysctl[cnt] = malloc(sizeof(struct sysctl_val));
2141 if (!opts.sysctl[cnt])
2142 return ENOMEM;
2143
2144 /* replace '.' with '/' in entry name */
2145 tc = tmp = strdup(blobmsg_name(cur));
2146 while ((tc = strchr(tc, '.')))
2147 *tc = '/';
2148
2149 opts.sysctl[cnt]->value = strdup(blobmsg_get_string(cur));
2150 opts.sysctl[cnt]->entry = tmp;
2151
2152 ++cnt;
2153 }
2154
2155 opts.sysctl[cnt] = NULL;
2156
2157 return 0;
2158 }
2159
2160
2161 enum {
2162 OCI_LINUX_CGROUPSPATH,
2163 OCI_LINUX_RESOURCES,
2164 OCI_LINUX_SECCOMP,
2165 OCI_LINUX_SYSCTL,
2166 OCI_LINUX_NAMESPACES,
2167 OCI_LINUX_DEVICES,
2168 OCI_LINUX_UIDMAPPINGS,
2169 OCI_LINUX_GIDMAPPINGS,
2170 OCI_LINUX_MASKEDPATHS,
2171 OCI_LINUX_READONLYPATHS,
2172 OCI_LINUX_ROOTFSPROPAGATION,
2173 __OCI_LINUX_MAX,
2174 };
2175
2176 static const struct blobmsg_policy oci_linux_policy[] = {
2177 [OCI_LINUX_CGROUPSPATH] = { "cgroupsPath", BLOBMSG_TYPE_STRING },
2178 [OCI_LINUX_RESOURCES] = { "resources", BLOBMSG_TYPE_TABLE },
2179 [OCI_LINUX_SECCOMP] = { "seccomp", BLOBMSG_TYPE_TABLE },
2180 [OCI_LINUX_SYSCTL] = { "sysctl", BLOBMSG_TYPE_TABLE },
2181 [OCI_LINUX_NAMESPACES] = { "namespaces", BLOBMSG_TYPE_ARRAY },
2182 [OCI_LINUX_DEVICES] = { "devices", BLOBMSG_TYPE_ARRAY },
2183 [OCI_LINUX_UIDMAPPINGS] = { "uidMappings", BLOBMSG_TYPE_ARRAY },
2184 [OCI_LINUX_GIDMAPPINGS] = { "gidMappings", BLOBMSG_TYPE_ARRAY },
2185 [OCI_LINUX_MASKEDPATHS] = { "maskedPaths", BLOBMSG_TYPE_ARRAY },
2186 [OCI_LINUX_READONLYPATHS] = { "readonlyPaths", BLOBMSG_TYPE_ARRAY },
2187 [OCI_LINUX_ROOTFSPROPAGATION] = { "rootfsPropagation", BLOBMSG_TYPE_STRING },
2188 };
2189
2190 static int parseOCIlinux(struct blob_attr *msg)
2191 {
2192 struct blob_attr *tb[__OCI_LINUX_MAX];
2193 struct blob_attr *cur;
2194 int rem;
2195 int res = 0;
2196 char *cgpath;
2197 char cgfullpath[256] = "/sys/fs/cgroup";
2198
2199 blobmsg_parse(oci_linux_policy, __OCI_LINUX_MAX, tb, blobmsg_data(msg), blobmsg_len(msg));
2200
2201 if (tb[OCI_LINUX_NAMESPACES]) {
2202 blobmsg_for_each_attr(cur, tb[OCI_LINUX_NAMESPACES], rem) {
2203 res = parseOCIlinuxns(cur);
2204 if (res)
2205 return res;
2206 }
2207 }
2208
2209 if (tb[OCI_LINUX_UIDMAPPINGS]) {
2210 res = parseOCIuidgidmappings(tb[OCI_LINUX_GIDMAPPINGS], 0);
2211 if (res)
2212 return res;
2213 }
2214
2215 if (tb[OCI_LINUX_GIDMAPPINGS]) {
2216 res = parseOCIuidgidmappings(tb[OCI_LINUX_GIDMAPPINGS], 1);
2217 if (res)
2218 return res;
2219 }
2220
2221 if (tb[OCI_LINUX_READONLYPATHS]) {
2222 blobmsg_for_each_attr(cur, tb[OCI_LINUX_READONLYPATHS], rem) {
2223 res = add_mount(NULL, blobmsg_get_string(cur), NULL, MS_BIND | MS_REC | MS_RDONLY, 0, NULL, 0);
2224 if (res)
2225 return res;
2226 }
2227 }
2228
2229 if (tb[OCI_LINUX_MASKEDPATHS]) {
2230 blobmsg_for_each_attr(cur, tb[OCI_LINUX_MASKEDPATHS], rem) {
2231 res = add_mount((void *)(-1), blobmsg_get_string(cur), NULL, 0, 0, NULL, 0);
2232 if (res)
2233 return res;
2234 }
2235 }
2236
2237 if (tb[OCI_LINUX_SYSCTL]) {
2238 res = parseOCIsysctl(tb[OCI_LINUX_SYSCTL]);
2239 if (res)
2240 return res;
2241 }
2242
2243 if (tb[OCI_LINUX_SECCOMP]) {
2244 opts.ociseccomp = parseOCIlinuxseccomp(tb[OCI_LINUX_SECCOMP]);
2245 if (!opts.ociseccomp)
2246 return EINVAL;
2247 }
2248
2249 if (tb[OCI_LINUX_DEVICES]) {
2250 res = parseOCIdevices(tb[OCI_LINUX_DEVICES]);
2251 if (res)
2252 return res;
2253 }
2254
2255 if (tb[OCI_LINUX_CGROUPSPATH]) {
2256 cgpath = blobmsg_get_string(tb[OCI_LINUX_CGROUPSPATH]);
2257 if (cgpath[0] == '/') {
2258 if (strlen(cgpath) + 1 >= (sizeof(cgfullpath) - strlen(cgfullpath)))
2259 return E2BIG;
2260
2261 strcat(cgfullpath, cgpath);
2262 } else {
2263 strcat(cgfullpath, "/containers/");
2264 if (strlen(opts.name) + strlen(cgpath) + 2 >= (sizeof(cgfullpath) - strlen(cgfullpath)))
2265 return E2BIG;
2266
2267 strcat(cgfullpath, opts.name); /* should be container name rather than jail name */
2268 strcat(cgfullpath, "/");
2269 strcat(cgfullpath, cgpath);
2270 }
2271 } else {
2272 strcat(cgfullpath, "/containers/");
2273 if (2 * strlen(opts.name) + 2 >= (sizeof(cgfullpath) - strlen(cgfullpath)))
2274 return E2BIG;
2275
2276 strcat(cgfullpath, opts.name); /* should be container name rather than jail name */
2277 strcat(cgfullpath, "/");
2278 strcat(cgfullpath, opts.name); /* should be container instance name rather than jail name */
2279 }
2280
2281 cgroups_init(cgfullpath);
2282
2283 if (tb[OCI_LINUX_RESOURCES]) {
2284 res = parseOCIlinuxcgroups(tb[OCI_LINUX_RESOURCES]);
2285 if (res)
2286 return res;
2287 }
2288
2289 return 0;
2290 }
2291
2292 enum {
2293 OCI_VERSION,
2294 OCI_HOSTNAME,
2295 OCI_PROCESS,
2296 OCI_ROOT,
2297 OCI_MOUNTS,
2298 OCI_HOOKS,
2299 OCI_LINUX,
2300 OCI_ANNOTATIONS,
2301 __OCI_MAX,
2302 };
2303
2304 static const struct blobmsg_policy oci_policy[] = {
2305 [OCI_VERSION] = { "ociVersion", BLOBMSG_TYPE_STRING },
2306 [OCI_HOSTNAME] = { "hostname", BLOBMSG_TYPE_STRING },
2307 [OCI_PROCESS] = { "process", BLOBMSG_TYPE_TABLE },
2308 [OCI_ROOT] = { "root", BLOBMSG_TYPE_TABLE },
2309 [OCI_MOUNTS] = { "mounts", BLOBMSG_TYPE_ARRAY },
2310 [OCI_HOOKS] = { "hooks", BLOBMSG_TYPE_TABLE },
2311 [OCI_LINUX] = { "linux", BLOBMSG_TYPE_TABLE },
2312 [OCI_ANNOTATIONS] = { "annotations", BLOBMSG_TYPE_TABLE },
2313 };
2314
2315 static int parseOCI(const char *jsonfile)
2316 {
2317 struct blob_attr *tb[__OCI_MAX];
2318 struct blob_attr *cur;
2319 int rem;
2320 int res;
2321
2322 blob_buf_init(&ocibuf, 0);
2323
2324 if (!blobmsg_add_json_from_file(&ocibuf, jsonfile)) {
2325 res=ENOENT;
2326 goto errout;
2327 }
2328
2329 blobmsg_parse(oci_policy, __OCI_MAX, tb, blob_data(ocibuf.head), blob_len(ocibuf.head));
2330
2331 if (!tb[OCI_VERSION]) {
2332 res=ENOMSG;
2333 goto errout;
2334 }
2335
2336 if (strncmp("1.0", blobmsg_get_string(tb[OCI_VERSION]), 3)) {
2337 ERROR("unsupported ociVersion %s\n", blobmsg_get_string(tb[OCI_VERSION]));
2338 res=ENOTSUP;
2339 goto errout;
2340 }
2341
2342 if (tb[OCI_HOSTNAME])
2343 opts.hostname = strdup(blobmsg_get_string(tb[OCI_HOSTNAME]));
2344
2345 if (!tb[OCI_PROCESS]) {
2346 res=ENODATA;
2347 goto errout;
2348 }
2349
2350 if ((res = parseOCIprocess(tb[OCI_PROCESS])))
2351 goto errout;
2352
2353 if (!tb[OCI_ROOT]) {
2354 res=ENODATA;
2355 goto errout;
2356 }
2357 if ((res = parseOCIroot(jsonfile, tb[OCI_ROOT])))
2358 goto errout;
2359
2360 if (!tb[OCI_MOUNTS]) {
2361 res=ENODATA;
2362 goto errout;
2363 }
2364
2365 blobmsg_for_each_attr(cur, tb[OCI_MOUNTS], rem)
2366 if ((res = parseOCImount(cur)))
2367 goto errout;
2368
2369 if (tb[OCI_LINUX] && (res = parseOCIlinux(tb[OCI_LINUX])))
2370 goto errout;
2371
2372 if (tb[OCI_HOOKS] && (res = parseOCIhooks(tb[OCI_HOOKS])))
2373 goto errout;
2374
2375 if (tb[OCI_ANNOTATIONS])
2376 opts.annotations = blob_memdup(tb[OCI_ANNOTATIONS]);
2377
2378 errout:
2379 blob_buf_free(&ocibuf);
2380
2381 return res;
2382 }
2383
2384 static int set_oom_score_adj(void)
2385 {
2386 int f;
2387 char fname[32];
2388
2389 if (!opts.set_oom_score_adj)
2390 return 0;
2391
2392 snprintf(fname, sizeof(fname), "/proc/%u/oom_score_adj", jail_process.pid);
2393 f = open(fname, O_WRONLY | O_TRUNC);
2394 if (f < 0)
2395 return errno;
2396
2397 dprintf(f, "%d", opts.oom_score_adj);
2398 close(f);
2399
2400 return 0;
2401 }
2402
2403
2404 enum {
2405 OCI_STATE_CREATING,
2406 OCI_STATE_CREATED,
2407 OCI_STATE_RUNNING,
2408 OCI_STATE_STOPPED,
2409 };
2410
2411 static int jail_oci_state = OCI_STATE_CREATED;
2412 static void pipe_send_start_container(struct uloop_timeout *t);
2413 static struct uloop_timeout start_container_timeout = {
2414 .cb = pipe_send_start_container,
2415 };
2416
2417 static int handle_start(struct ubus_context *ctx, struct ubus_object *obj,
2418 struct ubus_request_data *req, const char *method,
2419 struct blob_attr *msg)
2420 {
2421 if (jail_oci_state != OCI_STATE_CREATED)
2422 return UBUS_STATUS_INVALID_ARGUMENT;
2423
2424 uloop_timeout_add(&start_container_timeout);
2425
2426 return UBUS_STATUS_OK;
2427 }
2428
2429 static struct blob_buf bb;
2430 static int handle_state(struct ubus_context *ctx, struct ubus_object *obj,
2431 struct ubus_request_data *req, const char *method,
2432 struct blob_attr *msg)
2433 {
2434 char *statusstr;
2435
2436 switch (jail_oci_state) {
2437 case OCI_STATE_CREATING:
2438 statusstr = "creating";
2439 break;
2440 case OCI_STATE_CREATED:
2441 statusstr = "created";
2442 break;
2443 case OCI_STATE_RUNNING:
2444 statusstr = "running";
2445 break;
2446 case OCI_STATE_STOPPED:
2447 statusstr = "stopped";
2448 break;
2449 default:
2450 statusstr = "unknown";
2451 }
2452
2453 blob_buf_init(&bb, 0);
2454 blobmsg_add_string(&bb, "ociVersion", OCI_VERSION_STRING);
2455 blobmsg_add_string(&bb, "id", opts.name);
2456 blobmsg_add_string(&bb, "status", statusstr);
2457 if (jail_oci_state == OCI_STATE_CREATED ||
2458 jail_oci_state == OCI_STATE_RUNNING)
2459 blobmsg_add_u32(&bb, "pid", jail_process.pid);
2460
2461 blobmsg_add_string(&bb, "bundle", opts.ocibundle);
2462
2463 if (opts.annotations)
2464 blobmsg_add_blob(&bb, opts.annotations);
2465
2466 ubus_send_reply(ctx, req, bb.head);
2467
2468 return UBUS_STATUS_OK;
2469 }
2470
2471 enum {
2472 CONTAINER_KILL_ATTR_SIGNAL,
2473 __CONTAINER_KILL_ATTR_MAX,
2474 };
2475
2476 static const struct blobmsg_policy container_kill_attrs[__CONTAINER_KILL_ATTR_MAX] = {
2477 [CONTAINER_KILL_ATTR_SIGNAL] = { "signal", BLOBMSG_TYPE_INT32 },
2478 };
2479
2480 static int
2481 container_handle_kill(struct ubus_context *ctx, struct ubus_object *obj,
2482 struct ubus_request_data *req, const char *method,
2483 struct blob_attr *msg)
2484 {
2485 struct blob_attr *tb[__CONTAINER_KILL_ATTR_MAX], *cur;
2486 int sig = SIGTERM;
2487
2488 blobmsg_parse(container_kill_attrs, __CONTAINER_KILL_ATTR_MAX, tb, blobmsg_data(msg), blobmsg_data_len(msg));
2489
2490 cur = tb[CONTAINER_KILL_ATTR_SIGNAL];
2491 if (cur)
2492 sig = blobmsg_get_u32(cur);
2493
2494 if (jail_oci_state == OCI_STATE_CREATING)
2495 return UBUS_STATUS_NOT_FOUND;
2496
2497 if (kill(jail_process.pid, sig) == 0)
2498 return 0;
2499
2500 switch (errno) {
2501 case EINVAL: return UBUS_STATUS_INVALID_ARGUMENT;
2502 case EPERM: return UBUS_STATUS_PERMISSION_DENIED;
2503 case ESRCH: return UBUS_STATUS_NOT_FOUND;
2504 }
2505
2506 return UBUS_STATUS_UNKNOWN_ERROR;
2507 }
2508
2509 static int
2510 jail_writepid(pid_t pid)
2511 {
2512 FILE *_pidfile;
2513
2514 if (!opts.pidfile)
2515 return 0;
2516
2517 _pidfile = fopen(opts.pidfile, "w");
2518 if (_pidfile == NULL)
2519 return errno;
2520
2521 if (fprintf(_pidfile, "%d\n", pid) < 0) {
2522 fclose(_pidfile);
2523 return errno;
2524 }
2525
2526 if (fclose(_pidfile))
2527 return errno;
2528
2529 return 0;
2530 }
2531
2532 static int checkpath(const char *path)
2533 {
2534 int dirfd = open(path, O_RDONLY | O_DIRECTORY | O_CLOEXEC);
2535 if (dirfd < 0) {
2536 ERROR("path %s open failed %m\n", path);
2537 return -1;
2538 }
2539 close(dirfd);
2540
2541 return 0;
2542 }
2543
2544 static struct ubus_method container_methods[] = {
2545 UBUS_METHOD_NOARG("start", handle_start),
2546 UBUS_METHOD_NOARG("state", handle_state),
2547 UBUS_METHOD("kill", container_handle_kill, container_kill_attrs),
2548 };
2549
2550 static struct ubus_object_type container_object_type =
2551 UBUS_OBJECT_TYPE("container", container_methods);
2552
2553 static struct ubus_object container_object = {
2554 .type = &container_object_type,
2555 .methods = container_methods,
2556 .n_methods = ARRAY_SIZE(container_methods),
2557 };
2558
2559 static void post_main(struct uloop_timeout *t);
2560 static struct uloop_timeout post_main_timeout = {
2561 .cb = post_main,
2562 };
2563 static int netns_fd;
2564 static int pidns_fd;
2565 #ifdef CLONE_NEWTIME
2566 static int timens_fd;
2567 #endif
2568 static void post_create_runtime(void);
2569
2570 struct env_e {
2571 struct list_head list;
2572 char *envarg;
2573 };
2574
2575 int main(int argc, char **argv)
2576 {
2577 uid_t uid = getuid();
2578 const char log[] = "/dev/log";
2579 const char ubus[] = "/var/run/ubus/ubus.sock";
2580 int ret = EXIT_FAILURE;
2581 int ch;
2582 char *tmp;
2583 struct list_head envl = LIST_HEAD_INIT(envl);
2584 struct env_e *enve, *tmpenve;
2585 unsigned short int envn = 0, envc = 0;
2586
2587 if (uid) {
2588 ERROR("not root, aborting: %m\n");
2589 return EXIT_FAILURE;
2590 }
2591
2592 /* those are filehandlers, so -1 indicates unused */
2593 opts.setns.pid = -1;
2594 opts.setns.net = -1;
2595 opts.setns.ns = -1;
2596 opts.setns.ipc = -1;
2597 opts.setns.uts = -1;
2598 opts.setns.user = -1;
2599 opts.setns.cgroup = -1;
2600 #ifdef CLONE_NEWTIME
2601 opts.setns.time = -1;
2602 #endif
2603
2604 /* default 5 seconds timeout after SIGTERM before SIGKILL is sent */
2605 opts.term_timeout = 5;
2606
2607 umask(022);
2608 mount_list_init();
2609 init_library_search();
2610 cgroups_prepare();
2611 exit_from_child = false;
2612
2613 while ((ch = getopt(argc, argv, OPT_ARGS)) != -1) {
2614 switch (ch) {
2615 case 'd':
2616 debug = atoi(optarg);
2617 break;
2618 case 'e':
2619 enve = calloc(1, sizeof(*enve));
2620 enve->envarg = optarg;
2621 list_add_tail(&enve->list, &envl);
2622 break;
2623 case 'p':
2624 opts.namespace |= CLONE_NEWNS;
2625 opts.procfs = 1;
2626 break;
2627 case 'o':
2628 opts.namespace |= CLONE_NEWNS;
2629 opts.ronly = 1;
2630 break;
2631 case 'f':
2632 opts.namespace |= CLONE_NEWUSER;
2633 break;
2634 case 'F':
2635 opts.namespace |= CLONE_NEWCGROUP;
2636 break;
2637 case 'R':
2638 opts.extroot = realpath(optarg, NULL);
2639 break;
2640 case 's':
2641 opts.namespace |= CLONE_NEWNS;
2642 opts.sysfs = 1;
2643 break;
2644 case 'S':
2645 opts.seccomp = optarg;
2646 add_mount_bind(optarg, 1, -1);
2647 break;
2648 case 'C':
2649 opts.capabilities = optarg;
2650 break;
2651 case 'c':
2652 opts.no_new_privs = 1;
2653 break;
2654 case 'n':
2655 opts.name = optarg;
2656 break;
2657 case 'N':
2658 opts.namespace |= CLONE_NEWNET;
2659 break;
2660 case 'h':
2661 opts.namespace |= CLONE_NEWUTS;
2662 opts.hostname = strdup(optarg);
2663 break;
2664 case 'j':
2665 jail_join_ns(optarg);
2666 break;
2667 case 'r':
2668 opts.namespace |= CLONE_NEWNS;
2669 tmp = strchr(optarg, ':');
2670 if (tmp) {
2671 *(tmp++) = '\0';
2672 add_2paths_and_deps(optarg, tmp, 1, 0, 0);
2673 } else {
2674 add_path_and_deps(optarg, 1, 0, 0);
2675 }
2676 break;
2677 case 'w':
2678 opts.namespace |= CLONE_NEWNS;
2679 tmp = strchr(optarg, ':');
2680 if (tmp) {
2681 *(tmp++) = '\0';
2682 add_2paths_and_deps(optarg, tmp, 0, 0, 0);
2683 } else {
2684 add_path_and_deps(optarg, 0, 0, 0);
2685 }
2686 break;
2687 case 'u':
2688 opts.namespace |= CLONE_NEWNS;
2689 add_mount_bind(ubus, 0, -1);
2690 break;
2691 case 'l':
2692 opts.namespace |= CLONE_NEWNS;
2693 add_mount_bind(log, 0, -1);
2694 break;
2695 case 'U':
2696 opts.user = optarg;
2697 break;
2698 case 'G':
2699 opts.group = optarg;
2700 break;
2701 case 'O':
2702 opts.overlaydir = realpath(optarg, NULL);
2703 break;
2704 case 't':
2705 opts.term_timeout = atoi(optarg);
2706 break;
2707 case 'T':
2708 opts.tmpoverlaysize = optarg;
2709 break;
2710 case 'E':
2711 opts.require_jail = 1;
2712 break;
2713 case 'y':
2714 opts.console = 1;
2715 break;
2716 case 'J':
2717 opts.ocibundle = optarg;
2718 break;
2719 case 'i':
2720 opts.immediately = true;
2721 break;
2722 case 'P':
2723 opts.pidfile = optarg;
2724 break;
2725 }
2726 }
2727
2728 if (opts.namespace && !opts.ocibundle)
2729 opts.namespace |= CLONE_NEWIPC | CLONE_NEWPID;
2730
2731 /*
2732 * env import from cmdline is not available for OCI containers
2733 */
2734 if (opts.ocibundle && !list_empty(&envl)) {
2735 ret=-ENOTSUP;
2736 goto errout;
2737 }
2738
2739 /*
2740 * prepare list of env variables to import for slim containers
2741 */
2742 if (!list_empty(&envl)) {
2743 list_for_each_entry(enve, &envl, list)
2744 ++envn;
2745
2746 opts.envp = calloc(1 + envn, sizeof(char*));
2747 list_for_each_entry_safe(enve, tmpenve, &envl, list) {
2748 tmp = getenv(enve->envarg);
2749 if (tmp) {
2750 ret = asprintf(&opts.envp[envc++], "%s=%s", enve->envarg, tmp);
2751 if (ret < 0) {
2752 ERROR("filed to handle envargs %s\n", tmp);
2753 free(enve);
2754 goto errout;
2755 }
2756 }
2757
2758 list_del(&enve->list);
2759 free(enve);
2760 }
2761
2762 opts.envp[envc] = NULL;
2763 }
2764
2765 /*
2766 * uid in parent user namespace representing root user in new
2767 * user namespace, defaults to nobody unless specified in uidMappings
2768 */
2769 opts.root_map_uid = 65534;
2770
2771 if (opts.capabilities && parseOCIcapabilities_from_file(&opts.capset, opts.capabilities)) {
2772 ERROR("failed to read capabilities from file %s\n", opts.capabilities);
2773 ret=-1;
2774 goto errout;
2775 }
2776
2777 if (opts.ocibundle) {
2778 char *jsonfile;
2779 int ocires;
2780
2781 if (!opts.name) {
2782 ERROR("OCI bundle needs a named jail\n");
2783 ret=-1;
2784 goto errout;
2785 }
2786 if (asprintf(&jsonfile, "%s/config.json", opts.ocibundle) < 0) {
2787 ret=-ENOMEM;
2788 goto errout;
2789 }
2790 ocires = parseOCI(jsonfile);
2791 free(jsonfile);
2792 if (ocires) {
2793 ERROR("parsing of OCI JSON spec has failed: %s (%d)\n", strerror(ocires), ocires);
2794 ret=ocires;
2795 goto errout;
2796 }
2797 }
2798
2799 if (opts.namespace & CLONE_NEWNET) {
2800 if (!opts.name) {
2801 ERROR("netns needs a named jail\n");
2802 ret=-1;
2803 goto errout;
2804 }
2805 }
2806
2807
2808 if (opts.tmpoverlaysize && strlen(opts.tmpoverlaysize) > 8) {
2809 ERROR("size parameter too long: \"%s\"\n", opts.tmpoverlaysize);
2810 ret=-1;
2811 goto errout;
2812 }
2813
2814 if (opts.extroot && checkpath(opts.extroot)) {
2815 ERROR("invalid rootfs path '%s'", opts.extroot);
2816 ret=-1;
2817 goto errout;
2818 }
2819
2820 if (opts.overlaydir && checkpath(opts.overlaydir)) {
2821 ERROR("invalid rootfs overlay path '%s'", opts.overlaydir);
2822 ret=-1;
2823 goto errout;
2824 }
2825
2826 /* no <binary> param found */
2827 if (!opts.ocibundle && (argc - optind < 1)) {
2828 usage();
2829 ret=EXIT_FAILURE;
2830 goto errout;
2831 }
2832 if (!(opts.ocibundle||opts.namespace||opts.capabilities||opts.seccomp||
2833 (opts.setns.net != -1) ||
2834 (opts.setns.ns != -1) ||
2835 (opts.setns.ipc != -1) ||
2836 (opts.setns.uts != -1) ||
2837 (opts.setns.user != -1) ||
2838 (opts.setns.cgroup != -1))) {
2839 ERROR("Not using namespaces, capabilities or seccomp !!!\n\n");
2840 usage();
2841 ret=EXIT_FAILURE;
2842 goto errout;
2843 }
2844 DEBUG("Using namespaces(0x%08x), capabilities(%d), seccomp(%d)\n",
2845 opts.namespace,
2846 opts.capset.apply,
2847 opts.seccomp != 0 || opts.ociseccomp != 0);
2848
2849 uloop_init();
2850 signals_init();
2851
2852 parent_ctx = ubus_connect(NULL);
2853 ubus_add_uloop(parent_ctx);
2854
2855 if (opts.ocibundle) {
2856 char *objname;
2857 if (asprintf(&objname, "container.%s", opts.name) < 0) {
2858 ret=-ENOMEM;
2859 goto errout;
2860 }
2861
2862 container_object.name = objname;
2863 ret = ubus_add_object(parent_ctx, &container_object);
2864 if (ret) {
2865 ERROR("Failed to add object: %s\n", ubus_strerror(ret));
2866 ret=-1;
2867 goto errout;
2868 }
2869 }
2870
2871 /* deliberately not using 'else' on unrelated conditional branches */
2872 if (!opts.ocibundle) {
2873 /* allocate NULL-terminated array for argv */
2874 opts.jail_argv = calloc(1 + argc - optind, sizeof(void *));
2875 if (!opts.jail_argv) {
2876 ret=EXIT_FAILURE;
2877 goto errout;
2878 }
2879 for (size_t s = optind; s < argc; s++)
2880 opts.jail_argv[s - optind] = strdup(argv[s]);
2881
2882 if (opts.namespace & CLONE_NEWUSER)
2883 get_jail_user(&opts.pw_uid, &opts.pw_gid, &opts.gr_gid);
2884 }
2885
2886 if (!opts.extroot) {
2887 if (opts.namespace && add_path_and_deps(*opts.jail_argv, 1, -1, 0)) {
2888 ERROR("failed to load dependencies\n");
2889 ret=-1;
2890 goto errout;
2891 }
2892 }
2893
2894 if (opts.namespace && opts.seccomp && add_path_and_deps("libpreload-seccomp.so", 1, -1, 1)) {
2895 ERROR("failed to load libpreload-seccomp.so\n");
2896 opts.seccomp = 0;
2897 if (opts.require_jail) {
2898 ret=-1;
2899 goto errout;
2900 }
2901 }
2902
2903 uloop_timeout_add(&post_main_timeout);
2904 uloop_run();
2905
2906 errout:
2907 if (opts.ocibundle)
2908 cgroups_free();
2909
2910 free_opts(true);
2911
2912 return ret;
2913 }
2914
2915 static void post_main(struct uloop_timeout *t)
2916 {
2917 if (apply_rlimits()) {
2918 ERROR("error applying resource limits\n");
2919 free_and_exit(EXIT_FAILURE);
2920 }
2921
2922 if (opts.name)
2923 prctl(PR_SET_NAME, opts.name, NULL, NULL, NULL);
2924
2925 if (pipe(&pipes[0]) < 0 || pipe(&pipes[2]) < 0)
2926 free_and_exit(-1);
2927
2928 if (has_namespaces()) {
2929 if (opts.namespace & CLONE_NEWNS) {
2930 if (!opts.extroot && (opts.user || opts.group)) {
2931 add_mount_bind("/etc/passwd", 1, -1);
2932 add_mount_bind("/etc/group", 1, -1);
2933 }
2934
2935 #if defined(__GLIBC__)
2936 if (!opts.extroot)
2937 add_mount_bind("/etc/nsswitch.conf", 1, -1);
2938 #endif
2939 if (opts.setns.ns == -1) {
2940 if (!(opts.namespace & CLONE_NEWNET)) {
2941 add_mount_bind("/etc/resolv.conf", 1, 0);
2942 } else {
2943 /* new mount namespace to provide /dev/resolv.conf.d */
2944 char hostdir[PATH_MAX];
2945
2946 snprintf(hostdir, PATH_MAX, "/tmp/resolv.conf-%s.d", opts.name);
2947 mkdir_p(hostdir, 0755);
2948 add_mount(hostdir, "/dev/resolv.conf.d", NULL,
2949 MS_BIND | MS_NOEXEC | MS_NOATIME | MS_NOSUID | MS_NODEV | MS_RDONLY, 0, NULL, 0);
2950 }
2951 }
2952 /* default mounts */
2953 add_mount(NULL, "/dev", "tmpfs", MS_NOATIME | MS_NOEXEC | MS_NOSUID, 0, "size=1M", -1);
2954 add_mount(NULL, "/dev/pts", "devpts", MS_NOATIME | MS_NOEXEC | MS_NOSUID, 0, "newinstance,ptmxmode=0666,mode=0620,gid=5", 0);
2955
2956 if (opts.procfs || opts.ocibundle) {
2957 add_mount("proc", "/proc", "proc", MS_NOATIME | MS_NODEV | MS_NOEXEC | MS_NOSUID, 0, NULL, -1);
2958
2959 /*
2960 * hack to make /proc/sys/net read-write while the rest of /proc/sys is read-only
2961 * which cannot be expressed with OCI spec, but happends to be very useful.
2962 * Only apply it if '/proc/sys' is not already listed as mount, maskedPath or
2963 * readonlyPath.
2964 * If not running in a new network namespace, only make /proc/sys read-only.
2965 * If running in a new network namespace, temporarily stash (ie. mount-bind)
2966 * /proc/sys/net into (totally unrelated, but surely existing) /proc/self/net.
2967 * Then we mount-bind /proc/sys read-only and then mount-move /proc/self/net into
2968 * /proc/sys/net.
2969 * This works because mounts are executed in incrementing strcmp() order and
2970 * /proc/self/net appears there before /proc/sys/net and hence the operation
2971 * succeeds as the bind-mount of /proc/self/net is performed first and then
2972 * move-mount of /proc/sys/net follows because 'e' preceeds 'y' in the ASCII
2973 * table (and in the alphabet).
2974 */
2975 if (!add_mount(NULL, "/proc/sys", NULL, MS_BIND | MS_RDONLY, 0, NULL, -1))
2976 if (opts.namespace & CLONE_NEWNET)
2977 if (!add_mount_inner("/proc/self/net", "/proc/sys/net", NULL, MS_MOVE, 0, NULL, -1))
2978 add_mount_inner("/proc/sys/net", "/proc/self/net", NULL, MS_BIND, 0, NULL, -1);
2979
2980 }
2981 if (opts.sysfs || opts.ocibundle)
2982 add_mount("sysfs", "/sys", "sysfs", MS_RELATIME | MS_NODEV | MS_NOEXEC | MS_NOSUID | MS_RDONLY, 0, NULL, -1);
2983
2984 if (opts.ocibundle)
2985 add_mount("shm", "/dev/shm", "tmpfs", MS_NOSUID | MS_NOEXEC | MS_NODEV, 0, "mode=1777", -1);
2986
2987 }
2988
2989 if (opts.setns.pid != -1) {
2990 pidns_fd = ns_open_pid("pid", getpid());
2991 setns_open(CLONE_NEWPID);
2992 } else {
2993 pidns_fd = -1;
2994 }
2995
2996 #ifdef CLONE_NEWTIME
2997 if (opts.setns.time != -1) {
2998 timens_fd = ns_open_pid("time", getpid());
2999 setns_open(CLONE_NEWTIME);
3000 } else {
3001 timens_fd = -1;
3002 }
3003 #endif
3004
3005 if (opts.namespace & CLONE_NEWUSER) {
3006 if (prctl(PR_SET_SECUREBITS, SECBIT_NO_SETUID_FIXUP)) {
3007 ERROR("prctl(PR_SET_SECUREBITS) failed: %m\n");
3008 free_and_exit(EXIT_FAILURE);
3009 }
3010 if (seteuid(opts.root_map_uid)) {
3011 ERROR("seteuid(%d) failed: %m\n", opts.root_map_uid);
3012 free_and_exit(EXIT_FAILURE);
3013 }
3014 }
3015
3016 jail_process.pid = clone(exec_jail, child_stack + STACK_SIZE, SIGCHLD | (opts.namespace & (~CLONE_NEWCGROUP)), NULL);
3017 } else {
3018 jail_process.pid = fork();
3019 }
3020
3021 if (jail_process.pid > 0) {
3022 /* parent process */
3023 char sig_buf[1];
3024
3025 uloop_process_add(&jail_process);
3026 jail_running = 1;
3027 if (seteuid(0)) {
3028 ERROR("seteuid(%d) failed: %m\n", opts.root_map_uid);
3029 free_and_exit(EXIT_FAILURE);
3030 }
3031
3032 prctl(PR_SET_SECUREBITS, 0);
3033
3034 if (pidns_fd != -1) {
3035 setns(pidns_fd, CLONE_NEWPID);
3036 close(pidns_fd);
3037 }
3038 #ifdef CLONE_NEWTIME
3039 if (timens_fd != -1) {
3040 setns(timens_fd, CLONE_NEWTIME);
3041 close(timens_fd);
3042 }
3043 #endif
3044 if (opts.setns.net != -1)
3045 close(opts.setns.net);
3046 if (opts.setns.ns != -1)
3047 close(opts.setns.ns);
3048 if (opts.setns.ipc != -1)
3049 close(opts.setns.ipc);
3050 if (opts.setns.uts != -1)
3051 close(opts.setns.uts);
3052 if (opts.setns.user != -1)
3053 close(opts.setns.user);
3054 if (opts.setns.cgroup != -1)
3055 close(opts.setns.cgroup);
3056 close(pipes[1]);
3057 close(pipes[2]);
3058 if (read(pipes[0], sig_buf, 1) < 1) {
3059 ERROR("can't read from child\n");
3060 free_and_exit(-1);
3061 }
3062 close(pipes[0]);
3063 set_oom_score_adj();
3064
3065 if (opts.ocibundle)
3066 cgroups_apply(jail_process.pid);
3067
3068 if (opts.namespace & CLONE_NEWUSER) {
3069 if (write_setgroups(jail_process.pid, true)) {
3070 ERROR("can't write setgroups\n");
3071 free_and_exit(-1);
3072 }
3073 if (!opts.uidmap) {
3074 bool has_gr = (opts.gr_gid != -1);
3075 if (opts.pw_uid != -1) {
3076 write_single_uid_gid_map(jail_process.pid, 0, opts.pw_uid);
3077 write_single_uid_gid_map(jail_process.pid, 1, has_gr?opts.gr_gid:opts.pw_gid);
3078 } else {
3079 write_single_uid_gid_map(jail_process.pid, 0, 65534);
3080 write_single_uid_gid_map(jail_process.pid, 1, has_gr?opts.gr_gid:65534);
3081 }
3082 } else {
3083 write_uid_gid_map(jail_process.pid, 0, opts.uidmap);
3084 if (opts.gidmap)
3085 write_uid_gid_map(jail_process.pid, 1, opts.gidmap);
3086 }
3087 }
3088
3089 if (opts.namespace & CLONE_NEWNET)
3090 jail_network_start(parent_ctx, opts.name, jail_process.pid);
3091
3092 if (jail_writepid(jail_process.pid)) {
3093 ERROR("failed to write pidfile: %m\n");
3094 free_and_exit(-1);
3095 }
3096 } else if (jail_process.pid == 0) {
3097 /* fork child process */
3098 free_and_exit(exec_jail(NULL));
3099 } else {
3100 ERROR("failed to clone/fork: %m\n");
3101 free_and_exit(EXIT_FAILURE);
3102 }
3103 run_hooks(opts.hooks.createRuntime, post_create_runtime);
3104 }
3105
3106 static void post_poststart(void);
3107 static void post_create_runtime(void)
3108 {
3109 char sig_buf[1];
3110
3111 sig_buf[0] = 'O';
3112 if (write(pipes[3], sig_buf, 1) < 0) {
3113 ERROR("can't write to child\n");
3114 free_and_exit(-1);
3115 }
3116
3117 jail_oci_state = OCI_STATE_CREATED;
3118 if (opts.ocibundle && !opts.immediately)
3119 uloop_run(); /* wait for 'start' command via ubus */
3120 else
3121 pipe_send_start_container(NULL);
3122 }
3123
3124 static void pipe_send_start_container(struct uloop_timeout *t)
3125 {
3126 char sig_buf[1];
3127
3128 jail_oci_state = OCI_STATE_RUNNING;
3129 sig_buf[0] = '!';
3130 if (write(pipes[3], sig_buf, 1) < 0) {
3131 ERROR("can't write to child\n");
3132 free_and_exit(-1);
3133 }
3134 close(pipes[3]);
3135
3136 run_hooks(opts.hooks.poststart, post_poststart);
3137 }
3138
3139 static void post_poststart(void)
3140 {
3141 uloop_run(); /* idle here while jail is running */
3142 if (jail_running) {
3143 DEBUG("uloop interrupted, killing jail process\n");
3144 kill(jail_process.pid, SIGTERM);
3145 uloop_timeout_set(&jail_process_timeout, 1000);
3146 uloop_run();
3147 }
3148 uloop_done();
3149 poststop();
3150 }
3151
3152 static void post_poststop(void);
3153 static void poststop(void) {
3154 if (opts.namespace & CLONE_NEWNET) {
3155 setns(netns_fd, CLONE_NEWNET);
3156 jail_network_stop();
3157 close(netns_fd);
3158 }
3159 run_hooks(opts.hooks.poststop, post_poststop);
3160 }
3161
3162 static void post_poststop(void)
3163 {
3164 free_opts(true);
3165 if (parent_ctx)
3166 ubus_free(parent_ctx);
3167
3168 exit(jail_return_code);
3169 }
OpenWrt service / process manager