1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
2 
3 #include <sys/file.h>
4 #include <sys/mount.h>
5 
6 #include "alloc-util.h"
7 #include "bus-get-properties.h"
8 #include "bus-label.h"
9 #include "bus-polkit.h"
10 #include "copy.h"
11 #include "discover-image.h"
12 #include "dissect-image.h"
13 #include "fd-util.h"
14 #include "fileio.h"
15 #include "fs-util.h"
16 #include "image-dbus.h"
17 #include "io-util.h"
18 #include "loop-util.h"
19 #include "missing_capability.h"
20 #include "mount-util.h"
21 #include "os-util.h"
22 #include "process-util.h"
23 #include "raw-clone.h"
24 #include "strv.h"
25 #include "user-util.h"
26 
27 static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_type, image_type, ImageType);
28 
bus_image_method_remove(sd_bus_message * message,void * userdata,sd_bus_error * error)29 int bus_image_method_remove(
30                 sd_bus_message *message,
31                 void *userdata,
32                 sd_bus_error *error) {
33 
34         _cleanup_close_pair_ int errno_pipe_fd[2] = { -1, -1 };
35         Image *image = userdata;
36         Manager *m = image->userdata;
37         pid_t child;
38         int r;
39 
40         assert(message);
41         assert(image);
42 
43         if (m->n_operations >= OPERATIONS_MAX)
44                 return sd_bus_error_set(error, SD_BUS_ERROR_LIMITS_EXCEEDED, "Too many ongoing operations.");
45 
46         const char *details[] = {
47                 "image", image->name,
48                 "verb", "remove",
49                 NULL
50         };
51 
52         r = bus_verify_polkit_async(
53                         message,
54                         CAP_SYS_ADMIN,
55                         "org.freedesktop.machine1.manage-images",
56                         details,
57                         false,
58                         UID_INVALID,
59                         &m->polkit_registry,
60                         error);
61         if (r < 0)
62                 return r;
63         if (r == 0)
64                 return 1; /* Will call us back */
65 
66         if (pipe2(errno_pipe_fd, O_CLOEXEC|O_NONBLOCK) < 0)
67                 return sd_bus_error_set_errnof(error, errno, "Failed to create pipe: %m");
68 
69         r = safe_fork("(sd-imgrm)", FORK_RESET_SIGNALS, &child);
70         if (r < 0)
71                 return sd_bus_error_set_errnof(error, r, "Failed to fork(): %m");
72         if (r == 0) {
73                 errno_pipe_fd[0] = safe_close(errno_pipe_fd[0]);
74 
75                 r = image_remove(image);
76                 if (r < 0) {
77                         (void) write(errno_pipe_fd[1], &r, sizeof(r));
78                         _exit(EXIT_FAILURE);
79                 }
80 
81                 _exit(EXIT_SUCCESS);
82         }
83 
84         errno_pipe_fd[1] = safe_close(errno_pipe_fd[1]);
85 
86         r = operation_new(m, NULL, child, message, errno_pipe_fd[0], NULL);
87         if (r < 0) {
88                 (void) sigkill_wait(child);
89                 return r;
90         }
91 
92         errno_pipe_fd[0] = -1;
93 
94         return 1;
95 }
96 
bus_image_method_rename(sd_bus_message * message,void * userdata,sd_bus_error * error)97 int bus_image_method_rename(
98                 sd_bus_message *message,
99                 void *userdata,
100                 sd_bus_error *error) {
101 
102         Image *image = userdata;
103         Manager *m = image->userdata;
104         const char *new_name;
105         int r;
106 
107         assert(message);
108         assert(image);
109 
110         r = sd_bus_message_read(message, "s", &new_name);
111         if (r < 0)
112                 return r;
113 
114         if (!image_name_is_valid(new_name))
115                 return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Image name '%s' is invalid.", new_name);
116 
117         const char *details[] = {
118                 "image", image->name,
119                 "verb", "rename",
120                 "new_name", new_name,
121                 NULL
122         };
123 
124         r = bus_verify_polkit_async(
125                         message,
126                         CAP_SYS_ADMIN,
127                         "org.freedesktop.machine1.manage-images",
128                         details,
129                         false,
130                         UID_INVALID,
131                         &m->polkit_registry,
132                         error);
133         if (r < 0)
134                 return r;
135         if (r == 0)
136                 return 1; /* Will call us back */
137 
138         r = image_rename(image, new_name);
139         if (r < 0)
140                 return r;
141 
142         return sd_bus_reply_method_return(message, NULL);
143 }
144 
bus_image_method_clone(sd_bus_message * message,void * userdata,sd_bus_error * error)145 int bus_image_method_clone(
146                 sd_bus_message *message,
147                 void *userdata,
148                 sd_bus_error *error) {
149 
150         _cleanup_close_pair_ int errno_pipe_fd[2] = { -1, -1 };
151         Image *image = userdata;
152         Manager *m = image->userdata;
153         const char *new_name;
154         int r, read_only;
155         pid_t child;
156 
157         assert(message);
158         assert(image);
159         assert(m);
160 
161         if (m->n_operations >= OPERATIONS_MAX)
162                 return sd_bus_error_set(error, SD_BUS_ERROR_LIMITS_EXCEEDED, "Too many ongoing operations.");
163 
164         r = sd_bus_message_read(message, "sb", &new_name, &read_only);
165         if (r < 0)
166                 return r;
167 
168         if (!image_name_is_valid(new_name))
169                 return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Image name '%s' is invalid.", new_name);
170 
171         const char *details[] = {
172                 "image", image->name,
173                 "verb", "clone",
174                 "new_name", new_name,
175                 NULL
176         };
177 
178         r = bus_verify_polkit_async(
179                         message,
180                         CAP_SYS_ADMIN,
181                         "org.freedesktop.machine1.manage-images",
182                         details,
183                         false,
184                         UID_INVALID,
185                         &m->polkit_registry,
186                         error);
187         if (r < 0)
188                 return r;
189         if (r == 0)
190                 return 1; /* Will call us back */
191 
192         if (pipe2(errno_pipe_fd, O_CLOEXEC|O_NONBLOCK) < 0)
193                 return sd_bus_error_set_errnof(error, errno, "Failed to create pipe: %m");
194 
195         r = safe_fork("(sd-imgclone)", FORK_RESET_SIGNALS, &child);
196         if (r < 0)
197                 return sd_bus_error_set_errnof(error, r, "Failed to fork(): %m");
198         if (r == 0) {
199                 errno_pipe_fd[0] = safe_close(errno_pipe_fd[0]);
200 
201                 r = image_clone(image, new_name, read_only);
202                 if (r < 0) {
203                         (void) write(errno_pipe_fd[1], &r, sizeof(r));
204                         _exit(EXIT_FAILURE);
205                 }
206 
207                 _exit(EXIT_SUCCESS);
208         }
209 
210         errno_pipe_fd[1] = safe_close(errno_pipe_fd[1]);
211 
212         r = operation_new(m, NULL, child, message, errno_pipe_fd[0], NULL);
213         if (r < 0) {
214                 (void) sigkill_wait(child);
215                 return r;
216         }
217 
218         errno_pipe_fd[0] = -1;
219 
220         return 1;
221 }
222 
bus_image_method_mark_read_only(sd_bus_message * message,void * userdata,sd_bus_error * error)223 int bus_image_method_mark_read_only(
224                 sd_bus_message *message,
225                 void *userdata,
226                 sd_bus_error *error) {
227 
228         Image *image = userdata;
229         Manager *m = image->userdata;
230         int read_only, r;
231 
232         assert(message);
233 
234         r = sd_bus_message_read(message, "b", &read_only);
235         if (r < 0)
236                 return r;
237 
238         const char *details[] = {
239                 "image", image->name,
240                 "verb", "mark_read_only",
241                 "read_only", one_zero(read_only),
242                 NULL
243         };
244 
245         r = bus_verify_polkit_async(
246                         message,
247                         CAP_SYS_ADMIN,
248                         "org.freedesktop.machine1.manage-images",
249                         details,
250                         false,
251                         UID_INVALID,
252                         &m->polkit_registry,
253                         error);
254         if (r < 0)
255                 return r;
256         if (r == 0)
257                 return 1; /* Will call us back */
258 
259         r = image_read_only(image, read_only);
260         if (r < 0)
261                 return r;
262 
263         return sd_bus_reply_method_return(message, NULL);
264 }
265 
bus_image_method_set_limit(sd_bus_message * message,void * userdata,sd_bus_error * error)266 int bus_image_method_set_limit(
267                 sd_bus_message *message,
268                 void *userdata,
269                 sd_bus_error *error) {
270 
271         Image *image = userdata;
272         Manager *m = image->userdata;
273         uint64_t limit;
274         int r;
275 
276         assert(message);
277 
278         r = sd_bus_message_read(message, "t", &limit);
279         if (r < 0)
280                 return r;
281         if (!FILE_SIZE_VALID_OR_INFINITY(limit))
282                 return sd_bus_error_set(error, SD_BUS_ERROR_INVALID_ARGS, "New limit out of range");
283 
284         const char *details[] = {
285                 "machine", image->name,
286                 "verb", "set_limit",
287                 NULL
288         };
289 
290         r = bus_verify_polkit_async(
291                         message,
292                         CAP_SYS_ADMIN,
293                         "org.freedesktop.machine1.manage-images",
294                         details,
295                         false,
296                         UID_INVALID,
297                         &m->polkit_registry,
298                         error);
299         if (r < 0)
300                 return r;
301         if (r == 0)
302                 return 1; /* Will call us back */
303 
304         r = image_set_limit(image, limit);
305         if (r < 0)
306                 return r;
307 
308         return sd_bus_reply_method_return(message, NULL);
309 }
310 
bus_image_method_get_hostname(sd_bus_message * message,void * userdata,sd_bus_error * error)311 int bus_image_method_get_hostname(
312                 sd_bus_message *message,
313                 void *userdata,
314                 sd_bus_error *error) {
315 
316         Image *image = userdata;
317         int r;
318 
319         if (!image->metadata_valid) {
320                 r = image_read_metadata(image);
321                 if (r < 0)
322                         return sd_bus_error_set_errnof(error, r, "Failed to read image metadata: %m");
323         }
324 
325         return sd_bus_reply_method_return(message, "s", image->hostname);
326 }
327 
bus_image_method_get_machine_id(sd_bus_message * message,void * userdata,sd_bus_error * error)328 int bus_image_method_get_machine_id(
329                 sd_bus_message *message,
330                 void *userdata,
331                 sd_bus_error *error) {
332 
333         _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
334         Image *image = userdata;
335         int r;
336 
337         if (!image->metadata_valid) {
338                 r = image_read_metadata(image);
339                 if (r < 0)
340                         return sd_bus_error_set_errnof(error, r, "Failed to read image metadata: %m");
341         }
342 
343         r = sd_bus_message_new_method_return(message, &reply);
344         if (r < 0)
345                 return r;
346 
347         if (sd_id128_is_null(image->machine_id)) /* Add an empty array if the ID is zero */
348                 r = sd_bus_message_append(reply, "ay", 0);
349         else
350                 r = sd_bus_message_append_array(reply, 'y', image->machine_id.bytes, 16);
351         if (r < 0)
352                 return r;
353 
354         return sd_bus_send(NULL, reply, NULL);
355 }
356 
bus_image_method_get_machine_info(sd_bus_message * message,void * userdata,sd_bus_error * error)357 int bus_image_method_get_machine_info(
358                 sd_bus_message *message,
359                 void *userdata,
360                 sd_bus_error *error) {
361 
362         Image *image = userdata;
363         int r;
364 
365         if (!image->metadata_valid) {
366                 r = image_read_metadata(image);
367                 if (r < 0)
368                         return sd_bus_error_set_errnof(error, r, "Failed to read image metadata: %m");
369         }
370 
371         return bus_reply_pair_array(message, image->machine_info);
372 }
373 
bus_image_method_get_os_release(sd_bus_message * message,void * userdata,sd_bus_error * error)374 int bus_image_method_get_os_release(
375                 sd_bus_message *message,
376                 void *userdata,
377                 sd_bus_error *error) {
378 
379         Image *image = userdata;
380         int r;
381 
382         if (!image->metadata_valid) {
383                 r = image_read_metadata(image);
384                 if (r < 0)
385                         return sd_bus_error_set_errnof(error, r, "Failed to read image metadata: %m");
386         }
387 
388         return bus_reply_pair_array(message, image->os_release);
389 }
390 
image_flush_cache(sd_event_source * s,void * userdata)391 static int image_flush_cache(sd_event_source *s, void *userdata) {
392         Manager *m = userdata;
393 
394         assert(s);
395         assert(m);
396 
397         hashmap_clear(m->image_cache);
398         return 0;
399 }
400 
image_object_find(sd_bus * bus,const char * path,const char * interface,void * userdata,void ** found,sd_bus_error * error)401 static int image_object_find(sd_bus *bus, const char *path, const char *interface, void *userdata, void **found, sd_bus_error *error) {
402         _cleanup_free_ char *e = NULL;
403         Manager *m = userdata;
404         Image *image = NULL;
405         const char *p;
406         int r;
407 
408         assert(bus);
409         assert(path);
410         assert(interface);
411         assert(found);
412 
413         p = startswith(path, "/org/freedesktop/machine1/image/");
414         if (!p)
415                 return 0;
416 
417         e = bus_label_unescape(p);
418         if (!e)
419                 return -ENOMEM;
420 
421         image = hashmap_get(m->image_cache, e);
422         if (image) {
423                 *found = image;
424                 return 1;
425         }
426 
427         if (!m->image_cache_defer_event) {
428                 r = sd_event_add_defer(m->event, &m->image_cache_defer_event, image_flush_cache, m);
429                 if (r < 0)
430                         return r;
431 
432                 r = sd_event_source_set_priority(m->image_cache_defer_event, SD_EVENT_PRIORITY_IDLE);
433                 if (r < 0)
434                         return r;
435         }
436 
437         r = sd_event_source_set_enabled(m->image_cache_defer_event, SD_EVENT_ONESHOT);
438         if (r < 0)
439                 return r;
440 
441         r = image_find(IMAGE_MACHINE, e, NULL, &image);
442         if (r == -ENOENT)
443                 return 0;
444         if (r < 0)
445                 return r;
446 
447         image->userdata = m;
448 
449         r = hashmap_ensure_put(&m->image_cache, &image_hash_ops, image->name, image);
450         if (r < 0) {
451                 image_unref(image);
452                 return r;
453         }
454 
455         *found = image;
456         return 1;
457 }
458 
image_bus_path(const char * name)459 char *image_bus_path(const char *name) {
460         _cleanup_free_ char *e = NULL;
461 
462         assert(name);
463 
464         e = bus_label_escape(name);
465         if (!e)
466                 return NULL;
467 
468         return strjoin("/org/freedesktop/machine1/image/", e);
469 }
470 
image_node_enumerator(sd_bus * bus,const char * path,void * userdata,char *** nodes,sd_bus_error * error)471 static int image_node_enumerator(sd_bus *bus, const char *path, void *userdata, char ***nodes, sd_bus_error *error) {
472         _cleanup_hashmap_free_ Hashmap *images = NULL;
473         _cleanup_strv_free_ char **l = NULL;
474         Image *image;
475         int r;
476 
477         assert(bus);
478         assert(path);
479         assert(nodes);
480 
481         images = hashmap_new(&image_hash_ops);
482         if (!images)
483                 return -ENOMEM;
484 
485         r = image_discover(IMAGE_MACHINE, NULL, images);
486         if (r < 0)
487                 return r;
488 
489         HASHMAP_FOREACH(image, images) {
490                 char *p;
491 
492                 p = image_bus_path(image->name);
493                 if (!p)
494                         return -ENOMEM;
495 
496                 r = strv_consume(&l, p);
497                 if (r < 0)
498                         return r;
499         }
500 
501         *nodes = TAKE_PTR(l);
502 
503         return 1;
504 }
505 
506 const sd_bus_vtable image_vtable[] = {
507         SD_BUS_VTABLE_START(0),
508         SD_BUS_PROPERTY("Name", "s", NULL, offsetof(Image, name), 0),
509         SD_BUS_PROPERTY("Path", "s", NULL, offsetof(Image, path), 0),
510         SD_BUS_PROPERTY("Type", "s", property_get_type,  offsetof(Image, type), 0),
511         SD_BUS_PROPERTY("ReadOnly", "b", bus_property_get_bool, offsetof(Image, read_only), 0),
512         SD_BUS_PROPERTY("CreationTimestamp", "t", NULL, offsetof(Image, crtime), 0),
513         SD_BUS_PROPERTY("ModificationTimestamp", "t", NULL, offsetof(Image, mtime), 0),
514         SD_BUS_PROPERTY("Usage", "t", NULL, offsetof(Image, usage), 0),
515         SD_BUS_PROPERTY("Limit", "t", NULL, offsetof(Image, limit), 0),
516         SD_BUS_PROPERTY("UsageExclusive", "t", NULL, offsetof(Image, usage_exclusive), 0),
517         SD_BUS_PROPERTY("LimitExclusive", "t", NULL, offsetof(Image, limit_exclusive), 0),
518         SD_BUS_METHOD("Remove", NULL, NULL, bus_image_method_remove, SD_BUS_VTABLE_UNPRIVILEGED),
519         SD_BUS_METHOD("Rename", "s", NULL, bus_image_method_rename, SD_BUS_VTABLE_UNPRIVILEGED),
520         SD_BUS_METHOD("Clone", "sb", NULL, bus_image_method_clone, SD_BUS_VTABLE_UNPRIVILEGED),
521         SD_BUS_METHOD("MarkReadOnly", "b", NULL, bus_image_method_mark_read_only, SD_BUS_VTABLE_UNPRIVILEGED),
522         SD_BUS_METHOD("SetLimit", "t", NULL, bus_image_method_set_limit, SD_BUS_VTABLE_UNPRIVILEGED),
523         SD_BUS_METHOD("GetHostname", NULL, "s", bus_image_method_get_hostname, SD_BUS_VTABLE_UNPRIVILEGED),
524         SD_BUS_METHOD("GetMachineID", NULL, "ay", bus_image_method_get_machine_id, SD_BUS_VTABLE_UNPRIVILEGED),
525         SD_BUS_METHOD("GetMachineInfo", NULL, "a{ss}", bus_image_method_get_machine_info, SD_BUS_VTABLE_UNPRIVILEGED),
526         SD_BUS_METHOD("GetOSRelease", NULL, "a{ss}", bus_image_method_get_os_release, SD_BUS_VTABLE_UNPRIVILEGED),
527         SD_BUS_VTABLE_END
528 };
529 
530 const BusObjectImplementation image_object = {
531         "/org/freedesktop/machine1/image",
532         "org.freedesktop.machine1.Image",
533         .fallback_vtables = BUS_FALLBACK_VTABLES({image_vtable, image_object_find}),
534         .node_enumerator = image_node_enumerator,
535 };
536