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Commit | Line | Data |
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758ad80c SH |
1 | /* lxcfs |
2 | * | |
b11c6ec0 | 3 | * Copyright © 2014-2016 Canonical, Inc |
758ad80c SH |
4 | * Author: Serge Hallyn <serge.hallyn@ubuntu.com> |
5 | * | |
f2799430 | 6 | * See COPYING file for details. |
758ad80c SH |
7 | */ |
8 | ||
758ad80c SH |
9 | #define FUSE_USE_VERSION 26 |
10 | ||
4e3f18fb | 11 | #include <alloca.h> |
758ad80c | 12 | #include <dirent.h> |
1ece80b2 CB |
13 | #include <dlfcn.h> |
14 | #include <errno.h> | |
758ad80c SH |
15 | #include <fcntl.h> |
16 | #include <fuse.h> | |
758ad80c | 17 | #include <libgen.h> |
b11c6ec0 | 18 | #include <pthread.h> |
1ece80b2 CB |
19 | #include <sched.h> |
20 | #include <stdbool.h> | |
21 | #include <stdio.h> | |
22 | #include <stdlib.h> | |
23 | #include <string.h> | |
24 | #include <time.h> | |
25 | #include <unistd.h> | |
26 | #include <wait.h> | |
41bb9357 | 27 | #include <linux/sched.h> |
5b2dfd85 | 28 | #include <sys/epoll.h> |
1ece80b2 CB |
29 | #include <sys/mount.h> |
30 | #include <sys/socket.h> | |
758ad80c | 31 | |
237e200e | 32 | #include "bindings.h" |
1ece80b2 | 33 | #include "config.h" // for VERSION |
758ad80c | 34 | |
237e200e | 35 | void *dlopen_handle; |
b11c6ec0 | 36 | |
237e200e | 37 | /* Functions to keep track of number of threads using the library */ |
6d1308cb | 38 | |
237e200e SH |
39 | static int users_count; |
40 | static pthread_mutex_t user_count_mutex = PTHREAD_MUTEX_INITIALIZER; | |
b11c6ec0 | 41 | static void lock_mutex(pthread_mutex_t *l) |
2c51f8dd | 42 | { |
b11c6ec0 | 43 | int ret; |
2c51f8dd | 44 | |
b11c6ec0 | 45 | if ((ret = pthread_mutex_lock(l)) != 0) { |
b8defc3d | 46 | lxcfs_error("returned:%d %s\n", ret, strerror(ret)); |
b11c6ec0 SH |
47 | exit(1); |
48 | } | |
49 | } | |
2c51f8dd | 50 | |
237e200e | 51 | static void unlock_mutex(pthread_mutex_t *l) |
23ce2127 | 52 | { |
237e200e | 53 | int ret; |
2dc17609 | 54 | |
237e200e | 55 | if ((ret = pthread_mutex_unlock(l)) != 0) { |
b8defc3d | 56 | lxcfs_error("returned:%d %s\n", ret, strerror(ret)); |
237e200e | 57 | exit(1); |
97f1f27b | 58 | } |
237e200e | 59 | } |
2dc17609 | 60 | |
237e200e SH |
61 | static void users_lock(void) |
62 | { | |
63 | lock_mutex(&user_count_mutex); | |
64 | } | |
b731895e | 65 | |
237e200e SH |
66 | static void users_unlock(void) |
67 | { | |
68 | unlock_mutex(&user_count_mutex); | |
69 | } | |
e1068397 | 70 | |
81d17d8f | 71 | static volatile sig_atomic_t need_reload; |
59120f04 | 72 | |
237e200e SH |
73 | /* do_reload - reload the dynamic library. Done under |
74 | * lock and when we know the user_count was 0 */ | |
75 | static void do_reload(void) | |
76 | { | |
b8defc3d CB |
77 | if (dlopen_handle) { |
78 | lxcfs_debug("%s\n", "Closing liblxcfs.so handle."); | |
237e200e | 79 | dlclose(dlopen_handle); |
b8defc3d | 80 | } |
e1068397 | 81 | |
59120f04 | 82 | /* First try loading using ld.so */ |
237e200e | 83 | dlopen_handle = dlopen("liblxcfs.so", RTLD_LAZY); |
b8defc3d CB |
84 | if (dlopen_handle) { |
85 | lxcfs_debug("%s\n", "Successfully called dlopen() on liblxcfs.so."); | |
59120f04 | 86 | goto good; |
b8defc3d | 87 | } |
59120f04 | 88 | |
7c82d95e | 89 | dlopen_handle = dlopen("/usr/lib/lxcfs/liblxcfs.so", RTLD_LAZY); |
237e200e | 90 | if (!dlopen_handle) { |
b8defc3d | 91 | lxcfs_error("Failed to open liblxcfs.so: %s.\n", dlerror()); |
237e200e | 92 | _exit(1); |
2dc17609 | 93 | } |
59120f04 SH |
94 | |
95 | good: | |
96 | if (need_reload) | |
b8defc3d | 97 | lxcfs_error("%s\n", "lxcfs: reloaded"); |
237e200e | 98 | need_reload = 0; |
23ce2127 SH |
99 | } |
100 | ||
237e200e | 101 | static void up_users(void) |
23ce2127 | 102 | { |
237e200e SH |
103 | users_lock(); |
104 | if (users_count == 0 && need_reload) | |
105 | do_reload(); | |
106 | users_count++; | |
107 | users_unlock(); | |
108 | } | |
23ce2127 | 109 | |
237e200e SH |
110 | static void down_users(void) |
111 | { | |
112 | users_lock(); | |
113 | users_count--; | |
114 | users_unlock(); | |
23ce2127 SH |
115 | } |
116 | ||
237e200e SH |
117 | static void reload_handler(int sig) |
118 | { | |
237e200e | 119 | need_reload = 1; |
237e200e | 120 | } |
23ce2127 | 121 | |
237e200e SH |
122 | /* Functions to run the library methods */ |
123 | static int do_cg_getattr(const char *path, struct stat *sb) | |
aeb56147 | 124 | { |
237e200e SH |
125 | int (*cg_getattr)(const char *path, struct stat *sb); |
126 | char *error; | |
127 | dlerror(); /* Clear any existing error */ | |
128 | cg_getattr = (int (*)(const char *, struct stat *)) dlsym(dlopen_handle, "cg_getattr"); | |
129 | error = dlerror(); | |
130 | if (error != NULL) { | |
b8defc3d | 131 | lxcfs_error("%s\n", error); |
237e200e SH |
132 | return -1; |
133 | } | |
aeb56147 | 134 | |
237e200e | 135 | return cg_getattr(path, sb); |
aeb56147 SH |
136 | } |
137 | ||
237e200e | 138 | static int do_proc_getattr(const char *path, struct stat *sb) |
23ce2127 | 139 | { |
237e200e SH |
140 | int (*proc_getattr)(const char *path, struct stat *sb); |
141 | char *error; | |
142 | dlerror(); /* Clear any existing error */ | |
143 | proc_getattr = (int (*)(const char *, struct stat *)) dlsym(dlopen_handle, "proc_getattr"); | |
144 | error = dlerror(); | |
145 | if (error != NULL) { | |
b8defc3d | 146 | lxcfs_error("%s\n", error); |
237e200e SH |
147 | return -1; |
148 | } | |
23ce2127 | 149 | |
237e200e | 150 | return proc_getattr(path, sb); |
23ce2127 SH |
151 | } |
152 | ||
237e200e | 153 | static int do_cg_read(const char *path, char *buf, size_t size, off_t offset, |
23ce2127 SH |
154 | struct fuse_file_info *fi) |
155 | { | |
237e200e SH |
156 | int (*cg_read)(const char *path, char *buf, size_t size, off_t offset, |
157 | struct fuse_file_info *fi); | |
158 | char *error; | |
23ce2127 | 159 | |
237e200e SH |
160 | dlerror(); /* Clear any existing error */ |
161 | cg_read = (int (*)(const char *, char *, size_t, off_t, struct fuse_file_info *)) dlsym(dlopen_handle, "cg_read"); | |
162 | error = dlerror(); | |
163 | if (error != NULL) { | |
b8defc3d | 164 | lxcfs_error("%s\n", error); |
237e200e | 165 | return -1; |
23ce2127 SH |
166 | } |
167 | ||
237e200e | 168 | return cg_read(path, buf, size, offset, fi); |
23ce2127 SH |
169 | } |
170 | ||
237e200e | 171 | static int do_proc_read(const char *path, char *buf, size_t size, off_t offset, |
23ce2127 SH |
172 | struct fuse_file_info *fi) |
173 | { | |
237e200e SH |
174 | int (*proc_read)(const char *path, char *buf, size_t size, off_t offset, |
175 | struct fuse_file_info *fi); | |
176 | char *error; | |
aeb56147 | 177 | |
237e200e SH |
178 | dlerror(); /* Clear any existing error */ |
179 | proc_read = (int (*)(const char *, char *, size_t, off_t, struct fuse_file_info *)) dlsym(dlopen_handle, "proc_read"); | |
180 | error = dlerror(); | |
181 | if (error != NULL) { | |
b8defc3d | 182 | lxcfs_error("%s\n", error); |
237e200e | 183 | return -1; |
97f1f27b YY |
184 | } |
185 | ||
237e200e SH |
186 | return proc_read(path, buf, size, offset, fi); |
187 | } | |
97f1f27b | 188 | |
237e200e SH |
189 | static int do_cg_write(const char *path, const char *buf, size_t size, off_t offset, |
190 | struct fuse_file_info *fi) | |
191 | { | |
192 | int (*cg_write)(const char *path, const char *buf, size_t size, off_t offset, | |
193 | struct fuse_file_info *fi); | |
194 | char *error; | |
195 | dlerror(); /* Clear any existing error */ | |
196 | cg_write = (int (*)(const char *, const char *, size_t, off_t, struct fuse_file_info *)) dlsym(dlopen_handle, "cg_write"); | |
197 | error = dlerror(); | |
198 | if (error != NULL) { | |
b8defc3d | 199 | lxcfs_error("%s\n", error); |
237e200e | 200 | return -1; |
97f1f27b YY |
201 | } |
202 | ||
237e200e | 203 | return cg_write(path, buf, size, offset, fi); |
23ce2127 SH |
204 | } |
205 | ||
237e200e | 206 | static int do_cg_mkdir(const char *path, mode_t mode) |
41bb9357 | 207 | { |
237e200e SH |
208 | int (*cg_mkdir)(const char *path, mode_t mode); |
209 | char *error; | |
210 | dlerror(); /* Clear any existing error */ | |
211 | cg_mkdir = (int (*)(const char *, mode_t)) dlsym(dlopen_handle, "cg_mkdir"); | |
212 | error = dlerror(); | |
213 | if (error != NULL) { | |
b8defc3d | 214 | lxcfs_error("%s\n", error); |
237e200e SH |
215 | return -1; |
216 | } | |
41bb9357 | 217 | |
237e200e | 218 | return cg_mkdir(path, mode); |
41bb9357 SH |
219 | } |
220 | ||
237e200e | 221 | static int do_cg_chown(const char *path, uid_t uid, gid_t gid) |
0b6af11b | 222 | { |
237e200e SH |
223 | int (*cg_chown)(const char *path, uid_t uid, gid_t gid); |
224 | char *error; | |
225 | dlerror(); /* Clear any existing error */ | |
226 | cg_chown = (int (*)(const char *, uid_t, gid_t)) dlsym(dlopen_handle, "cg_chown"); | |
227 | error = dlerror(); | |
228 | if (error != NULL) { | |
b8defc3d | 229 | lxcfs_error("%s\n", error); |
237e200e SH |
230 | return -1; |
231 | } | |
0b6af11b | 232 | |
237e200e | 233 | return cg_chown(path, uid, gid); |
41bb9357 SH |
234 | } |
235 | ||
237e200e | 236 | static int do_cg_rmdir(const char *path) |
23ce2127 | 237 | { |
237e200e SH |
238 | int (*cg_rmdir)(const char *path); |
239 | char *error; | |
240 | dlerror(); /* Clear any existing error */ | |
241 | cg_rmdir = (int (*)(const char *path)) dlsym(dlopen_handle, "cg_rmdir"); | |
242 | error = dlerror(); | |
243 | if (error != NULL) { | |
b8defc3d | 244 | lxcfs_error("%s\n", error); |
237e200e | 245 | return -1; |
97f1f27b YY |
246 | } |
247 | ||
237e200e SH |
248 | return cg_rmdir(path); |
249 | } | |
f6c0b279 | 250 | |
237e200e SH |
251 | static int do_cg_chmod(const char *path, mode_t mode) |
252 | { | |
253 | int (*cg_chmod)(const char *path, mode_t mode); | |
254 | char *error; | |
255 | dlerror(); /* Clear any existing error */ | |
256 | cg_chmod = (int (*)(const char *, mode_t)) dlsym(dlopen_handle, "cg_chmod"); | |
257 | error = dlerror(); | |
258 | if (error != NULL) { | |
b8defc3d | 259 | lxcfs_error("%s\n", error); |
237e200e | 260 | return -1; |
e1068397 | 261 | } |
cdcdb29b | 262 | |
237e200e | 263 | return cg_chmod(path, mode); |
23ce2127 SH |
264 | } |
265 | ||
237e200e | 266 | static int do_cg_readdir(const char *path, void *buf, fuse_fill_dir_t filler, off_t offset, |
49878439 YY |
267 | struct fuse_file_info *fi) |
268 | { | |
237e200e SH |
269 | int (*cg_readdir)(const char *path, void *buf, fuse_fill_dir_t filler, off_t offset, |
270 | struct fuse_file_info *fi); | |
271 | char *error; | |
49878439 | 272 | |
237e200e SH |
273 | dlerror(); /* Clear any existing error */ |
274 | cg_readdir = (int (*)(const char *, void *, fuse_fill_dir_t, off_t, struct fuse_file_info *)) dlsym(dlopen_handle, "cg_readdir"); | |
275 | error = dlerror(); | |
276 | if (error != NULL) { | |
b8defc3d | 277 | lxcfs_error("%s\n", error); |
237e200e | 278 | return -1; |
97f1f27b | 279 | } |
49878439 | 280 | |
237e200e SH |
281 | return cg_readdir(path, buf, filler, offset, fi); |
282 | } | |
49878439 | 283 | |
237e200e SH |
284 | static int do_proc_readdir(const char *path, void *buf, fuse_fill_dir_t filler, off_t offset, |
285 | struct fuse_file_info *fi) | |
286 | { | |
287 | int (*proc_readdir)(const char *path, void *buf, fuse_fill_dir_t filler, off_t offset, | |
288 | struct fuse_file_info *fi); | |
289 | char *error; | |
49878439 | 290 | |
237e200e SH |
291 | dlerror(); /* Clear any existing error */ |
292 | proc_readdir = (int (*)(const char *, void *, fuse_fill_dir_t, off_t, struct fuse_file_info *)) dlsym(dlopen_handle, "proc_readdir"); | |
293 | error = dlerror(); | |
294 | if (error != NULL) { | |
b8defc3d | 295 | lxcfs_error("%s\n", error); |
237e200e | 296 | return -1; |
49878439 YY |
297 | } |
298 | ||
237e200e | 299 | return proc_readdir(path, buf, filler, offset, fi); |
49878439 YY |
300 | } |
301 | ||
237e200e | 302 | static int do_cg_open(const char *path, struct fuse_file_info *fi) |
23ce2127 | 303 | { |
237e200e SH |
304 | int (*cg_open)(const char *path, struct fuse_file_info *fi); |
305 | char *error; | |
306 | dlerror(); /* Clear any existing error */ | |
307 | cg_open = (int (*)(const char *, struct fuse_file_info *)) dlsym(dlopen_handle, "cg_open"); | |
308 | error = dlerror(); | |
309 | if (error != NULL) { | |
b8defc3d | 310 | lxcfs_error("%s\n", error); |
237e200e SH |
311 | return -1; |
312 | } | |
23ce2127 | 313 | |
237e200e | 314 | return cg_open(path, fi); |
23ce2127 SH |
315 | } |
316 | ||
bddbb106 SH |
317 | static int do_cg_access(const char *path, int mode) |
318 | { | |
319 | int (*cg_access)(const char *path, int mode); | |
320 | char *error; | |
321 | dlerror(); /* Clear any existing error */ | |
322 | cg_access = (int (*)(const char *, int mode)) dlsym(dlopen_handle, "cg_access"); | |
323 | error = dlerror(); | |
324 | if (error != NULL) { | |
b8defc3d | 325 | lxcfs_error("%s\n", error); |
bddbb106 SH |
326 | return -1; |
327 | } | |
328 | ||
329 | return cg_access(path, mode); | |
330 | } | |
331 | ||
237e200e | 332 | static int do_proc_open(const char *path, struct fuse_file_info *fi) |
758ad80c | 333 | { |
237e200e SH |
334 | int (*proc_open)(const char *path, struct fuse_file_info *fi); |
335 | char *error; | |
336 | dlerror(); /* Clear any existing error */ | |
337 | proc_open = (int (*)(const char *path, struct fuse_file_info *fi)) dlsym(dlopen_handle, "proc_open"); | |
338 | error = dlerror(); | |
339 | if (error != NULL) { | |
b8defc3d | 340 | lxcfs_error("%s\n", error); |
237e200e | 341 | return -1; |
35629743 SH |
342 | } |
343 | ||
237e200e | 344 | return proc_open(path, fi); |
35629743 SH |
345 | } |
346 | ||
bddbb106 SH |
347 | static int do_proc_access(const char *path, int mode) |
348 | { | |
349 | int (*proc_access)(const char *path, int mode); | |
350 | char *error; | |
351 | dlerror(); /* Clear any existing error */ | |
352 | proc_access = (int (*)(const char *, int mode)) dlsym(dlopen_handle, "proc_access"); | |
353 | error = dlerror(); | |
354 | if (error != NULL) { | |
b8defc3d | 355 | lxcfs_error("%s\n", error); |
bddbb106 SH |
356 | return -1; |
357 | } | |
358 | ||
359 | return proc_access(path, mode); | |
360 | } | |
361 | ||
237e200e | 362 | static int do_cg_release(const char *path, struct fuse_file_info *fi) |
35629743 | 363 | { |
237e200e SH |
364 | int (*cg_release)(const char *path, struct fuse_file_info *fi); |
365 | char *error; | |
366 | dlerror(); /* Clear any existing error */ | |
367 | cg_release = (int (*)(const char *path, struct fuse_file_info *)) dlsym(dlopen_handle, "cg_release"); | |
368 | error = dlerror(); | |
369 | if (error != NULL) { | |
b8defc3d | 370 | lxcfs_error("%s\n", error); |
237e200e SH |
371 | return -1; |
372 | } | |
373 | ||
374 | return cg_release(path, fi); | |
758ad80c SH |
375 | } |
376 | ||
237e200e | 377 | static int do_proc_release(const char *path, struct fuse_file_info *fi) |
35629743 | 378 | { |
237e200e SH |
379 | int (*proc_release)(const char *path, struct fuse_file_info *fi); |
380 | char *error; | |
381 | dlerror(); /* Clear any existing error */ | |
382 | proc_release = (int (*)(const char *path, struct fuse_file_info *)) dlsym(dlopen_handle, "proc_release"); | |
383 | error = dlerror(); | |
384 | if (error != NULL) { | |
b8defc3d | 385 | lxcfs_error("%s\n", error); |
237e200e SH |
386 | return -1; |
387 | } | |
97f1f27b | 388 | |
237e200e | 389 | return proc_release(path, fi); |
96fc5ee6 SH |
390 | } |
391 | ||
237e200e | 392 | static int do_cg_opendir(const char *path, struct fuse_file_info *fi) |
96fc5ee6 | 393 | { |
237e200e SH |
394 | int (*cg_opendir)(const char *path, struct fuse_file_info *fi); |
395 | char *error; | |
396 | dlerror(); /* Clear any existing error */ | |
397 | cg_opendir = (int (*)(const char *path, struct fuse_file_info *fi)) dlsym(dlopen_handle, "cg_opendir"); | |
398 | error = dlerror(); | |
399 | if (error != NULL) { | |
b8defc3d | 400 | lxcfs_error("%s\n", error); |
237e200e SH |
401 | return -1; |
402 | } | |
96fc5ee6 | 403 | |
237e200e | 404 | return cg_opendir(path, fi); |
35629743 SH |
405 | } |
406 | ||
237e200e | 407 | static int do_cg_releasedir(const char *path, struct fuse_file_info *fi) |
35629743 | 408 | { |
237e200e SH |
409 | int (*cg_releasedir)(const char *path, struct fuse_file_info *fi); |
410 | char *error; | |
411 | dlerror(); /* Clear any existing error */ | |
412 | cg_releasedir = (int (*)(const char *path, struct fuse_file_info *)) dlsym(dlopen_handle, "cg_releasedir"); | |
413 | error = dlerror(); | |
414 | if (error != NULL) { | |
b8defc3d | 415 | lxcfs_error("%s\n", error); |
237e200e | 416 | return -1; |
96fc5ee6 | 417 | } |
237e200e SH |
418 | |
419 | return cg_releasedir(path, fi); | |
35629743 SH |
420 | } |
421 | ||
2ad6d2bd SH |
422 | /* |
423 | * FUSE ops for / | |
424 | * these just delegate to the /proc and /cgroup ops as | |
425 | * needed | |
426 | */ | |
758ad80c SH |
427 | |
428 | static int lxcfs_getattr(const char *path, struct stat *sb) | |
429 | { | |
237e200e | 430 | int ret; |
17e6e1e2 CB |
431 | struct timespec now; |
432 | ||
758ad80c | 433 | if (strcmp(path, "/") == 0) { |
17e6e1e2 CB |
434 | if (clock_gettime(CLOCK_REALTIME, &now) < 0) |
435 | return -EINVAL; | |
436 | sb->st_uid = sb->st_gid = 0; | |
437 | sb->st_atim = sb->st_mtim = sb->st_ctim = now; | |
438 | sb->st_size = 0; | |
758ad80c SH |
439 | sb->st_mode = S_IFDIR | 00755; |
440 | sb->st_nlink = 2; | |
441 | return 0; | |
442 | } | |
17e6e1e2 | 443 | |
758ad80c | 444 | if (strncmp(path, "/cgroup", 7) == 0) { |
237e200e SH |
445 | up_users(); |
446 | ret = do_cg_getattr(path, sb); | |
447 | down_users(); | |
448 | return ret; | |
758ad80c | 449 | } |
35629743 | 450 | if (strncmp(path, "/proc", 5) == 0) { |
237e200e SH |
451 | up_users(); |
452 | ret = do_proc_getattr(path, sb); | |
453 | down_users(); | |
454 | return ret; | |
758ad80c | 455 | } |
f9b24a3e | 456 | return -ENOENT; |
758ad80c SH |
457 | } |
458 | ||
459 | static int lxcfs_opendir(const char *path, struct fuse_file_info *fi) | |
460 | { | |
237e200e | 461 | int ret; |
758ad80c SH |
462 | if (strcmp(path, "/") == 0) |
463 | return 0; | |
464 | ||
465 | if (strncmp(path, "/cgroup", 7) == 0) { | |
237e200e SH |
466 | up_users(); |
467 | ret = do_cg_opendir(path, fi); | |
468 | down_users(); | |
469 | return ret; | |
758ad80c | 470 | } |
35629743 SH |
471 | if (strcmp(path, "/proc") == 0) |
472 | return 0; | |
473 | return -ENOENT; | |
758ad80c SH |
474 | } |
475 | ||
476 | static int lxcfs_readdir(const char *path, void *buf, fuse_fill_dir_t filler, off_t offset, | |
477 | struct fuse_file_info *fi) | |
478 | { | |
237e200e | 479 | int ret; |
758ad80c | 480 | if (strcmp(path, "/") == 0) { |
d639f863 CB |
481 | if (filler(buf, ".", NULL, 0) != 0 || |
482 | filler(buf, "..", NULL, 0) != 0 || | |
483 | filler(buf, "proc", NULL, 0) != 0 || | |
484 | filler(buf, "cgroup", NULL, 0) != 0) | |
f9b24a3e | 485 | return -ENOMEM; |
758ad80c SH |
486 | return 0; |
487 | } | |
237e200e SH |
488 | if (strncmp(path, "/cgroup", 7) == 0) { |
489 | up_users(); | |
490 | ret = do_cg_readdir(path, buf, filler, offset, fi); | |
491 | down_users(); | |
492 | return ret; | |
493 | } | |
494 | if (strcmp(path, "/proc") == 0) { | |
495 | up_users(); | |
496 | ret = do_proc_readdir(path, buf, filler, offset, fi); | |
497 | down_users(); | |
498 | return ret; | |
499 | } | |
f9b24a3e | 500 | return -ENOENT; |
758ad80c SH |
501 | } |
502 | ||
bddbb106 SH |
503 | static int lxcfs_access(const char *path, int mode) |
504 | { | |
505 | int ret; | |
17e6e1e2 | 506 | |
f9b24a3e | 507 | if (strcmp(path, "/") == 0 && (mode & W_OK) == 0) |
17e6e1e2 CB |
508 | return 0; |
509 | ||
bddbb106 SH |
510 | if (strncmp(path, "/cgroup", 7) == 0) { |
511 | up_users(); | |
512 | ret = do_cg_access(path, mode); | |
513 | down_users(); | |
514 | return ret; | |
515 | } | |
516 | if (strncmp(path, "/proc", 5) == 0) { | |
517 | up_users(); | |
518 | ret = do_proc_access(path, mode); | |
519 | down_users(); | |
520 | return ret; | |
521 | } | |
522 | ||
f9b24a3e | 523 | return -EACCES; |
bddbb106 SH |
524 | } |
525 | ||
758ad80c SH |
526 | static int lxcfs_releasedir(const char *path, struct fuse_file_info *fi) |
527 | { | |
237e200e | 528 | int ret; |
758ad80c SH |
529 | if (strcmp(path, "/") == 0) |
530 | return 0; | |
531 | if (strncmp(path, "/cgroup", 7) == 0) { | |
237e200e SH |
532 | up_users(); |
533 | ret = do_cg_releasedir(path, fi); | |
534 | down_users(); | |
535 | return ret; | |
758ad80c | 536 | } |
35629743 SH |
537 | if (strcmp(path, "/proc") == 0) |
538 | return 0; | |
758ad80c SH |
539 | return -EINVAL; |
540 | } | |
541 | ||
99978832 SH |
542 | static int lxcfs_open(const char *path, struct fuse_file_info *fi) |
543 | { | |
237e200e SH |
544 | int ret; |
545 | if (strncmp(path, "/cgroup", 7) == 0) { | |
546 | up_users(); | |
547 | ret = do_cg_open(path, fi); | |
548 | down_users(); | |
549 | return ret; | |
550 | } | |
551 | if (strncmp(path, "/proc", 5) == 0) { | |
552 | up_users(); | |
553 | ret = do_proc_open(path, fi); | |
554 | down_users(); | |
555 | return ret; | |
556 | } | |
99978832 | 557 | |
f9b24a3e | 558 | return -EACCES; |
99978832 SH |
559 | } |
560 | ||
561 | static int lxcfs_read(const char *path, char *buf, size_t size, off_t offset, | |
562 | struct fuse_file_info *fi) | |
563 | { | |
237e200e SH |
564 | int ret; |
565 | if (strncmp(path, "/cgroup", 7) == 0) { | |
566 | up_users(); | |
567 | ret = do_cg_read(path, buf, size, offset, fi); | |
568 | down_users(); | |
569 | return ret; | |
570 | } | |
571 | if (strncmp(path, "/proc", 5) == 0) { | |
572 | up_users(); | |
573 | ret = do_proc_read(path, buf, size, offset, fi); | |
574 | down_users(); | |
575 | return ret; | |
576 | } | |
99978832 SH |
577 | |
578 | return -EINVAL; | |
579 | } | |
580 | ||
2ad6d2bd SH |
581 | int lxcfs_write(const char *path, const char *buf, size_t size, off_t offset, |
582 | struct fuse_file_info *fi) | |
583 | { | |
237e200e | 584 | int ret; |
2ad6d2bd | 585 | if (strncmp(path, "/cgroup", 7) == 0) { |
237e200e SH |
586 | up_users(); |
587 | ret = do_cg_write(path, buf, size, offset, fi); | |
588 | down_users(); | |
589 | return ret; | |
2ad6d2bd SH |
590 | } |
591 | ||
592 | return -EINVAL; | |
593 | } | |
594 | ||
99978832 SH |
595 | static int lxcfs_flush(const char *path, struct fuse_file_info *fi) |
596 | { | |
597 | return 0; | |
598 | } | |
599 | ||
600 | static int lxcfs_release(const char *path, struct fuse_file_info *fi) | |
758ad80c | 601 | { |
237e200e SH |
602 | int ret; |
603 | if (strncmp(path, "/cgroup", 7) == 0) { | |
604 | up_users(); | |
605 | ret = do_cg_release(path, fi); | |
606 | down_users(); | |
607 | return ret; | |
608 | } | |
609 | if (strncmp(path, "/proc", 5) == 0) { | |
610 | up_users(); | |
611 | ret = do_proc_release(path, fi); | |
612 | down_users(); | |
613 | return ret; | |
614 | } | |
8f6e8f5e SH |
615 | |
616 | return -EINVAL; | |
99978832 SH |
617 | } |
618 | ||
619 | static int lxcfs_fsync(const char *path, int datasync, struct fuse_file_info *fi) | |
620 | { | |
621 | return 0; | |
758ad80c SH |
622 | } |
623 | ||
ab54b798 SH |
624 | int lxcfs_mkdir(const char *path, mode_t mode) |
625 | { | |
237e200e SH |
626 | int ret; |
627 | if (strncmp(path, "/cgroup", 7) == 0) { | |
628 | up_users(); | |
629 | ret = do_cg_mkdir(path, mode); | |
630 | down_users(); | |
631 | return ret; | |
632 | } | |
ab54b798 | 633 | |
f9b24a3e | 634 | return -EPERM; |
ab54b798 SH |
635 | } |
636 | ||
341b21ad SH |
637 | int lxcfs_chown(const char *path, uid_t uid, gid_t gid) |
638 | { | |
237e200e SH |
639 | int ret; |
640 | if (strncmp(path, "/cgroup", 7) == 0) { | |
641 | up_users(); | |
642 | ret = do_cg_chown(path, uid, gid); | |
643 | down_users(); | |
644 | return ret; | |
645 | } | |
341b21ad | 646 | |
f9b24a3e CB |
647 | if (strncmp(path, "/proc", 5) == 0) |
648 | return -EPERM; | |
649 | ||
650 | return -ENOENT; | |
341b21ad SH |
651 | } |
652 | ||
2ad6d2bd SH |
653 | /* |
654 | * cat first does a truncate before doing ops->write. This doesn't | |
655 | * really make sense for cgroups. So just return 0 always but do | |
656 | * nothing. | |
657 | */ | |
658 | int lxcfs_truncate(const char *path, off_t newsize) | |
659 | { | |
660 | if (strncmp(path, "/cgroup", 7) == 0) | |
661 | return 0; | |
f9b24a3e | 662 | return -EPERM; |
2ad6d2bd SH |
663 | } |
664 | ||
50d8d5b5 SH |
665 | int lxcfs_rmdir(const char *path) |
666 | { | |
237e200e SH |
667 | int ret; |
668 | if (strncmp(path, "/cgroup", 7) == 0) { | |
669 | up_users(); | |
670 | ret = do_cg_rmdir(path); | |
671 | down_users(); | |
672 | return ret; | |
673 | } | |
f9b24a3e | 674 | return -EPERM; |
50d8d5b5 SH |
675 | } |
676 | ||
fd2e4e03 SH |
677 | int lxcfs_chmod(const char *path, mode_t mode) |
678 | { | |
237e200e SH |
679 | int ret; |
680 | if (strncmp(path, "/cgroup", 7) == 0) { | |
681 | up_users(); | |
682 | ret = do_cg_chmod(path, mode); | |
683 | down_users(); | |
684 | return ret; | |
685 | } | |
f9b24a3e CB |
686 | |
687 | if (strncmp(path, "/proc", 5) == 0) | |
688 | return -EPERM; | |
689 | ||
690 | return -ENOENT; | |
fd2e4e03 SH |
691 | } |
692 | ||
758ad80c SH |
693 | const struct fuse_operations lxcfs_ops = { |
694 | .getattr = lxcfs_getattr, | |
695 | .readlink = NULL, | |
696 | .getdir = NULL, | |
697 | .mknod = NULL, | |
ab54b798 | 698 | .mkdir = lxcfs_mkdir, |
758ad80c | 699 | .unlink = NULL, |
50d8d5b5 | 700 | .rmdir = lxcfs_rmdir, |
758ad80c SH |
701 | .symlink = NULL, |
702 | .rename = NULL, | |
703 | .link = NULL, | |
fd2e4e03 | 704 | .chmod = lxcfs_chmod, |
341b21ad | 705 | .chown = lxcfs_chown, |
2ad6d2bd | 706 | .truncate = lxcfs_truncate, |
758ad80c | 707 | .utime = NULL, |
99978832 SH |
708 | |
709 | .open = lxcfs_open, | |
710 | .read = lxcfs_read, | |
711 | .release = lxcfs_release, | |
2ad6d2bd | 712 | .write = lxcfs_write, |
99978832 | 713 | |
758ad80c | 714 | .statfs = NULL, |
99978832 SH |
715 | .flush = lxcfs_flush, |
716 | .fsync = lxcfs_fsync, | |
758ad80c SH |
717 | |
718 | .setxattr = NULL, | |
719 | .getxattr = NULL, | |
720 | .listxattr = NULL, | |
721 | .removexattr = NULL, | |
722 | ||
723 | .opendir = lxcfs_opendir, | |
724 | .readdir = lxcfs_readdir, | |
725 | .releasedir = lxcfs_releasedir, | |
726 | ||
727 | .fsyncdir = NULL, | |
728 | .init = NULL, | |
729 | .destroy = NULL, | |
bddbb106 | 730 | .access = lxcfs_access, |
758ad80c SH |
731 | .create = NULL, |
732 | .ftruncate = NULL, | |
733 | .fgetattr = NULL, | |
734 | }; | |
735 | ||
c3fb7d7f | 736 | static void usage() |
758ad80c SH |
737 | { |
738 | fprintf(stderr, "Usage:\n"); | |
739 | fprintf(stderr, "\n"); | |
1de81503 DK |
740 | fprintf(stderr, "lxcfs [-f|-d] [-p pidfile] mountpoint\n"); |
741 | fprintf(stderr, " -f running foreground by default; -d enable debug output \n"); | |
e190ee91 | 742 | fprintf(stderr, " Default pidfile is %s/lxcfs.pid\n", RUNTIME_PATH); |
c3fb7d7f | 743 | fprintf(stderr, "lxcfs -h\n"); |
758ad80c SH |
744 | exit(1); |
745 | } | |
746 | ||
99978832 | 747 | static bool is_help(char *w) |
758ad80c SH |
748 | { |
749 | if (strcmp(w, "-h") == 0 || | |
750 | strcmp(w, "--help") == 0 || | |
751 | strcmp(w, "-help") == 0 || | |
752 | strcmp(w, "help") == 0) | |
753 | return true; | |
754 | return false; | |
755 | } | |
756 | ||
1de81503 | 757 | bool swallow_arg(int *argcp, char *argv[], char *which) |
0b0f73db SH |
758 | { |
759 | int i; | |
760 | ||
761 | for (i = 1; argv[i]; i++) { | |
762 | if (strcmp(argv[i], which) != 0) | |
763 | continue; | |
764 | for (; argv[i]; i++) { | |
765 | argv[i] = argv[i+1]; | |
766 | } | |
767 | (*argcp)--; | |
1de81503 | 768 | return true; |
0b0f73db | 769 | } |
1de81503 | 770 | return false; |
0b0f73db SH |
771 | } |
772 | ||
e190ee91 | 773 | bool swallow_option(int *argcp, char *argv[], char *opt, char **v) |
0b0f73db SH |
774 | { |
775 | int i; | |
776 | ||
777 | for (i = 1; argv[i]; i++) { | |
778 | if (!argv[i+1]) | |
779 | continue; | |
780 | if (strcmp(argv[i], opt) != 0) | |
781 | continue; | |
e190ee91 SH |
782 | do { |
783 | *v = strdup(argv[i+1]); | |
784 | } while (!*v); | |
0b0f73db SH |
785 | for (; argv[i+1]; i++) { |
786 | argv[i] = argv[i+2]; | |
787 | } | |
788 | (*argcp) -= 2; | |
e190ee91 | 789 | return true; |
0b0f73db | 790 | } |
e190ee91 | 791 | return false; |
0b0f73db SH |
792 | } |
793 | ||
e190ee91 SH |
794 | static int set_pidfile(char *pidfile) |
795 | { | |
796 | int fd; | |
797 | char buf[50]; | |
798 | struct flock fl; | |
799 | ||
800 | fl.l_type = F_WRLCK; | |
801 | fl.l_whence = SEEK_SET; | |
802 | fl.l_start = 0; | |
803 | fl.l_len = 0; | |
804 | ||
805 | fd = open(pidfile, O_RDWR | O_CREAT, S_IRUSR | S_IWUSR); | |
806 | if (fd == -1) { | |
b8defc3d | 807 | fprintf(stderr, "Could not open pidfile %s: %m\n", pidfile); |
e190ee91 SH |
808 | return -1; |
809 | } | |
810 | ||
811 | if (fcntl(fd, F_SETLK, &fl) == -1) { | |
812 | if (errno == EAGAIN || errno == EACCES) { | |
813 | fprintf(stderr, "PID file '%s' is already locked.\n", pidfile); | |
814 | close(fd); | |
815 | return -1; | |
816 | } | |
817 | fprintf(stderr, "Warning; unable to lock PID file, proceeding.\n"); | |
818 | } | |
819 | ||
820 | if (ftruncate(fd, 0) == -1) { | |
821 | fprintf(stderr, "Error truncating PID file '%s': %m", pidfile); | |
822 | close(fd); | |
823 | return -1; | |
824 | } | |
825 | ||
826 | snprintf(buf, 50, "%ld\n", (long) getpid()); | |
827 | if (write(fd, buf, strlen(buf)) != strlen(buf)) { | |
828 | fprintf(stderr, "Error writing to PID file '%s': %m", pidfile); | |
829 | close(fd); | |
830 | return -1; | |
831 | } | |
832 | ||
833 | return fd; | |
834 | } | |
835 | ||
758ad80c SH |
836 | int main(int argc, char *argv[]) |
837 | { | |
47f5266f CB |
838 | int ret = EXIT_FAILURE; |
839 | int pidfd = -1; | |
e190ee91 | 840 | char *pidfile = NULL, *v = NULL; |
29a73c2f | 841 | size_t pidfile_len; |
1de81503 | 842 | bool debug = false; |
0b0f73db SH |
843 | /* |
844 | * what we pass to fuse_main is: | |
1de81503 | 845 | * argv[0] -s [-f|-d] -o allow_other,directio argv[1] NULL |
0b0f73db | 846 | */ |
2c51f8dd SH |
847 | int nargs = 5, cnt = 0; |
848 | char *newargv[6]; | |
758ad80c | 849 | |
0b0f73db SH |
850 | /* accomodate older init scripts */ |
851 | swallow_arg(&argc, argv, "-s"); | |
852 | swallow_arg(&argc, argv, "-f"); | |
1de81503 | 853 | debug = swallow_arg(&argc, argv, "-d"); |
e190ee91 SH |
854 | if (swallow_option(&argc, argv, "-o", &v)) { |
855 | if (strcmp(v, "allow_other") != 0) { | |
856 | fprintf(stderr, "Warning: unexpected fuse option %s\n", v); | |
47f5266f | 857 | exit(EXIT_FAILURE); |
e190ee91 SH |
858 | } |
859 | free(v); | |
860 | v = NULL; | |
861 | } | |
862 | if (swallow_option(&argc, argv, "-p", &v)) | |
863 | pidfile = v; | |
0b0f73db | 864 | |
2e9c0b32 SH |
865 | if (argc == 2 && strcmp(argv[1], "--version") == 0) { |
866 | fprintf(stderr, "%s\n", VERSION); | |
47f5266f | 867 | exit(EXIT_SUCCESS); |
2e9c0b32 | 868 | } |
0b0f73db | 869 | if (argc != 2 || is_help(argv[1])) |
c3fb7d7f | 870 | usage(); |
758ad80c | 871 | |
59120f04 | 872 | do_reload(); |
8fad16cd | 873 | if (signal(SIGUSR1, reload_handler) == SIG_ERR) { |
8dcde249 | 874 | fprintf(stderr, "Error setting USR1 signal handler: %m\n"); |
47f5266f | 875 | goto out; |
8fad16cd | 876 | } |
e190ee91 | 877 | |
38a76a91 | 878 | newargv[cnt++] = argv[0]; |
1de81503 DK |
879 | if (debug) { |
880 | newargv[cnt++] = "-d"; | |
881 | } else { | |
882 | newargv[cnt++] = "-f"; | |
883 | } | |
38a76a91 | 884 | newargv[cnt++] = "-o"; |
f466a31e | 885 | newargv[cnt++] = "allow_other,direct_io,entry_timeout=0.5,attr_timeout=0.5"; |
38a76a91 SH |
886 | newargv[cnt++] = argv[1]; |
887 | newargv[cnt++] = NULL; | |
758ad80c | 888 | |
e190ee91 SH |
889 | if (!pidfile) { |
890 | pidfile_len = strlen(RUNTIME_PATH) + strlen("/lxcfs.pid") + 1; | |
891 | pidfile = alloca(pidfile_len); | |
892 | snprintf(pidfile, pidfile_len, "%s/lxcfs.pid", RUNTIME_PATH); | |
893 | } | |
894 | if ((pidfd = set_pidfile(pidfile)) < 0) | |
895 | goto out; | |
896 | ||
47f5266f CB |
897 | if (!fuse_main(nargs, newargv, &lxcfs_ops, NULL)) |
898 | ret = EXIT_SUCCESS; | |
237e200e | 899 | |
c0adec85 | 900 | out: |
47f5266f CB |
901 | if (dlopen_handle) |
902 | dlclose(dlopen_handle); | |
903 | if (pidfile) | |
904 | unlink(pidfile); | |
905 | if (pidfd > 0) | |
906 | close(pidfd); | |
47f5266f | 907 | exit(ret); |
2183082c | 908 | } |