Commit | Line | Data |
---|---|---|
60b6c79c | 1 | /* |
ab5be9fa MJ |
2 | * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca> |
3 | * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
4 | * Copyright (C) 2019 Jérémie Galarneau <jeremie.galarneau@efficios.com> | |
60b6c79c | 5 | * |
ab5be9fa | 6 | * SPDX-License-Identifier: GPL-2.0-only |
60b6c79c | 7 | * |
60b6c79c MD |
8 | */ |
9 | ||
6c1c0768 | 10 | #define _LGPL_SOURCE |
37ccf8ec FD |
11 | #include <assert.h> |
12 | #include <fcntl.h> | |
13 | #include <grp.h> | |
60b6c79c | 14 | #include <limits.h> |
37ccf8ec FD |
15 | #include <pwd.h> |
16 | #include <sched.h> | |
17 | #include <signal.h> | |
60b6c79c MD |
18 | #include <stdio.h> |
19 | #include <stdlib.h> | |
20 | #include <string.h> | |
60b6c79c | 21 | #include <sys/stat.h> |
37ccf8ec FD |
22 | #include <sys/types.h> |
23 | #include <sys/wait.h> | |
60b6c79c | 24 | #include <unistd.h> |
60b6c79c | 25 | |
0ae3cfc6 | 26 | #include <common/bytecode/bytecode.h> |
0ef03255 | 27 | #include <common/lttng-kernel.h> |
90e535ef | 28 | #include <common/common.h> |
3fd15a74 | 29 | #include <common/utils.h> |
edf4b93e | 30 | #include <common/compat/errno.h> |
e8fa9fb0 | 31 | #include <common/compat/getenv.h> |
c73f064a | 32 | #include <common/compat/string.h> |
2038dd6c JG |
33 | #include <common/unix.h> |
34 | #include <common/defaults.h> | |
241e0a5a | 35 | #include <common/lttng-elf.h> |
cb8d0d24 | 36 | #include <common/thread.h> |
241e0a5a FD |
37 | |
38 | #include <lttng/constant.h> | |
60b6c79c | 39 | |
c73f064a JR |
40 | #include <common/sessiond-comm/sessiond-comm.h> |
41 | #include <common/filter/filter-ast.h> | |
c73f064a | 42 | |
0857097f DG |
43 | #include "runas.h" |
44 | ||
37ccf8ec FD |
45 | #define GETPW_BUFFER_FALLBACK_SIZE 4096 |
46 | ||
7567352f | 47 | struct run_as_data; |
fe9f7760 FD |
48 | struct run_as_ret; |
49 | typedef int (*run_as_fct)(struct run_as_data *data, struct run_as_ret *ret_value); | |
c2b75c49 | 50 | |
93bed9fe JG |
51 | enum run_as_cmd { |
52 | RUN_AS_MKDIR, | |
53 | RUN_AS_MKDIRAT, | |
54 | RUN_AS_MKDIR_RECURSIVE, | |
55 | RUN_AS_MKDIRAT_RECURSIVE, | |
56 | RUN_AS_OPEN, | |
57 | RUN_AS_OPENAT, | |
58 | RUN_AS_UNLINK, | |
59 | RUN_AS_UNLINKAT, | |
60 | RUN_AS_RMDIR, | |
61 | RUN_AS_RMDIRAT, | |
62 | RUN_AS_RMDIR_RECURSIVE, | |
63 | RUN_AS_RMDIRAT_RECURSIVE, | |
64 | RUN_AS_RENAME, | |
65 | RUN_AS_RENAMEAT, | |
66 | RUN_AS_EXTRACT_ELF_SYMBOL_OFFSET, | |
67 | RUN_AS_EXTRACT_SDT_PROBE_OFFSETS, | |
c73f064a | 68 | RUN_AS_GENERATE_FILTER_BYTECODE, |
60b6c79c MD |
69 | }; |
70 | ||
93bed9fe JG |
71 | struct run_as_mkdir_data { |
72 | int dirfd; | |
73 | char path[LTTNG_PATH_MAX]; | |
74 | mode_t mode; | |
75 | } LTTNG_PACKED; | |
76 | ||
e11d277b | 77 | struct run_as_open_data { |
93bed9fe JG |
78 | int dirfd; |
79 | char path[LTTNG_PATH_MAX]; | |
60b6c79c MD |
80 | int flags; |
81 | mode_t mode; | |
93bed9fe | 82 | } LTTNG_PACKED; |
60b6c79c | 83 | |
4628484a | 84 | struct run_as_unlink_data { |
93bed9fe JG |
85 | int dirfd; |
86 | char path[LTTNG_PATH_MAX]; | |
87 | } LTTNG_PACKED; | |
4628484a | 88 | |
93bed9fe JG |
89 | struct run_as_rmdir_data { |
90 | int dirfd; | |
91 | char path[LTTNG_PATH_MAX]; | |
c73f064a | 92 | int flags; /* enum lttng_directory_handle_rmdir_recursive_flags. */ |
93bed9fe | 93 | } LTTNG_PACKED; |
7567352f | 94 | |
241e0a5a | 95 | struct run_as_extract_elf_symbol_offset_data { |
93bed9fe | 96 | int fd; |
241e0a5a | 97 | char function[LTTNG_SYMBOL_NAME_LEN]; |
93bed9fe | 98 | } LTTNG_PACKED; |
241e0a5a | 99 | |
0ef03255 | 100 | struct run_as_extract_sdt_probe_offsets_data { |
93bed9fe | 101 | int fd; |
0ef03255 FD |
102 | char probe_name[LTTNG_SYMBOL_NAME_LEN]; |
103 | char provider_name[LTTNG_SYMBOL_NAME_LEN]; | |
93bed9fe | 104 | } LTTNG_PACKED; |
0ef03255 | 105 | |
c73f064a JR |
106 | struct run_as_generate_filter_bytecode_data { |
107 | char filter_expression[LTTNG_FILTER_MAX_LEN]; | |
108 | } LTTNG_PACKED; | |
109 | ||
93bed9fe JG |
110 | struct run_as_rename_data { |
111 | /* | |
112 | * [0] = old_dirfd | |
113 | * [1] = new_dirfd | |
114 | */ | |
115 | int dirfds[2]; | |
116 | char old_path[LTTNG_PATH_MAX]; | |
117 | char new_path[LTTNG_PATH_MAX]; | |
118 | } LTTNG_PACKED; | |
fe9f7760 FD |
119 | |
120 | struct run_as_open_ret { | |
93bed9fe JG |
121 | int fd; |
122 | } LTTNG_PACKED; | |
fe9f7760 | 123 | |
241e0a5a FD |
124 | struct run_as_extract_elf_symbol_offset_ret { |
125 | uint64_t offset; | |
93bed9fe | 126 | } LTTNG_PACKED; |
241e0a5a | 127 | |
0ef03255 FD |
128 | struct run_as_extract_sdt_probe_offsets_ret { |
129 | uint32_t num_offset; | |
b8e2fb80 | 130 | uint64_t offsets[LTTNG_KERNEL_ABI_MAX_UPROBE_NUM]; |
93bed9fe | 131 | } LTTNG_PACKED; |
7567352f | 132 | |
c73f064a JR |
133 | struct run_as_generate_filter_bytecode_ret { |
134 | /* A lttng_bytecode_filter struct with 'dynamic' payload. */ | |
135 | char bytecode[LTTNG_FILTER_MAX_LEN]; | |
136 | } LTTNG_PACKED; | |
137 | ||
7567352f MD |
138 | struct run_as_data { |
139 | enum run_as_cmd cmd; | |
140 | union { | |
93bed9fe | 141 | struct run_as_mkdir_data mkdir; |
7567352f MD |
142 | struct run_as_open_data open; |
143 | struct run_as_unlink_data unlink; | |
93bed9fe JG |
144 | struct run_as_rmdir_data rmdir; |
145 | struct run_as_rename_data rename; | |
241e0a5a | 146 | struct run_as_extract_elf_symbol_offset_data extract_elf_symbol_offset; |
0ef03255 | 147 | struct run_as_extract_sdt_probe_offsets_data extract_sdt_probe_offsets; |
c73f064a | 148 | struct run_as_generate_filter_bytecode_data generate_filter_bytecode; |
7567352f MD |
149 | } u; |
150 | uid_t uid; | |
151 | gid_t gid; | |
93bed9fe | 152 | } LTTNG_PACKED; |
4628484a | 153 | |
fe9f7760 FD |
154 | /* |
155 | * The run_as_ret structure holds the returned value and status of the command. | |
156 | * | |
157 | * The `u` union field holds the return value of the command; in most cases it | |
158 | * represents the success or the failure of the command. In more complex | |
159 | * commands, it holds a computed value. | |
160 | * | |
161 | * The _errno field is the errno recorded after the execution of the command. | |
162 | * | |
163 | * The _error fields is used the signify that return status of the command. For | |
164 | * simple commands returning `int` the _error field will be the same as the | |
165 | * ret_int field. In complex commands, it signify the success or failure of the | |
166 | * command. | |
167 | * | |
168 | */ | |
df5b86c8 | 169 | struct run_as_ret { |
fe9f7760 | 170 | union { |
93bed9fe | 171 | int ret; |
fe9f7760 | 172 | struct run_as_open_ret open; |
241e0a5a | 173 | struct run_as_extract_elf_symbol_offset_ret extract_elf_symbol_offset; |
0ef03255 | 174 | struct run_as_extract_sdt_probe_offsets_ret extract_sdt_probe_offsets; |
c73f064a | 175 | struct run_as_generate_filter_bytecode_ret generate_filter_bytecode; |
fe9f7760 | 176 | } u; |
df5b86c8 | 177 | int _errno; |
fe9f7760 | 178 | bool _error; |
93bed9fe JG |
179 | } LTTNG_PACKED; |
180 | ||
181 | #define COMMAND_IN_FDS(data_ptr) ({ \ | |
182 | int *fds = NULL; \ | |
183 | if (command_properties[data_ptr->cmd].in_fds_offset != -1) { \ | |
184 | fds = (int *) ((char *) data_ptr + command_properties[data_ptr->cmd].in_fds_offset); \ | |
185 | } \ | |
186 | fds; \ | |
187 | }) | |
188 | ||
189 | #define COMMAND_OUT_FDS(cmd, ret_ptr) ({ \ | |
190 | int *fds = NULL; \ | |
191 | if (command_properties[cmd].out_fds_offset != -1) { \ | |
192 | fds = (int *) ((char *) ret_ptr + command_properties[cmd].out_fds_offset); \ | |
193 | } \ | |
194 | fds; \ | |
195 | }) | |
196 | ||
197 | #define COMMAND_IN_FD_COUNT(data_ptr) ({ \ | |
198 | command_properties[data_ptr->cmd].in_fd_count; \ | |
199 | }) | |
200 | ||
201 | #define COMMAND_OUT_FD_COUNT(cmd) ({ \ | |
202 | command_properties[cmd].out_fd_count; \ | |
203 | }) | |
204 | ||
205 | #define COMMAND_USE_CWD_FD(data_ptr) command_properties[data_ptr->cmd].use_cwd_fd | |
206 | ||
207 | struct run_as_command_properties { | |
208 | /* Set to -1 when not applicable. */ | |
209 | ptrdiff_t in_fds_offset, out_fds_offset; | |
210 | unsigned int in_fd_count, out_fd_count; | |
211 | bool use_cwd_fd; | |
212 | }; | |
213 | ||
214 | static const struct run_as_command_properties command_properties[] = { | |
215 | [RUN_AS_MKDIR] = { | |
216 | .in_fds_offset = offsetof(struct run_as_data, u.mkdir.dirfd), | |
217 | .in_fd_count = 1, | |
218 | .out_fds_offset = -1, | |
219 | .out_fd_count = 0, | |
220 | .use_cwd_fd = true, | |
221 | }, | |
222 | [RUN_AS_MKDIRAT] = { | |
223 | .in_fds_offset = offsetof(struct run_as_data, u.mkdir.dirfd), | |
224 | .in_fd_count = 1, | |
225 | .out_fds_offset = -1, | |
226 | .out_fd_count = 0, | |
227 | .use_cwd_fd = false, | |
228 | }, | |
229 | [RUN_AS_MKDIR_RECURSIVE] = { | |
230 | .in_fds_offset = offsetof(struct run_as_data, u.mkdir.dirfd), | |
231 | .in_fd_count = 1, | |
232 | .out_fds_offset = -1, | |
233 | .out_fd_count = 0, | |
234 | .use_cwd_fd = true, | |
235 | }, | |
236 | [RUN_AS_MKDIRAT_RECURSIVE] = { | |
237 | .in_fds_offset = offsetof(struct run_as_data, u.mkdir.dirfd), | |
238 | .in_fd_count = 1, | |
239 | .out_fds_offset = -1, | |
240 | .out_fd_count = 0, | |
241 | .use_cwd_fd = false, | |
242 | }, | |
243 | [RUN_AS_OPEN] = { | |
244 | .in_fds_offset = offsetof(struct run_as_data, u.open.dirfd), | |
245 | .in_fd_count = 1, | |
246 | .out_fds_offset = offsetof(struct run_as_ret, u.open.fd), | |
247 | .out_fd_count = 1, | |
248 | .use_cwd_fd = true, | |
249 | }, | |
250 | [RUN_AS_OPENAT] = { | |
251 | .in_fds_offset = offsetof(struct run_as_data, u.open.dirfd), | |
252 | .in_fd_count = 1, | |
253 | .out_fds_offset = offsetof(struct run_as_ret, u.open.fd), | |
254 | .out_fd_count = 1, | |
255 | .use_cwd_fd = false, | |
256 | }, | |
257 | [RUN_AS_UNLINK] = { | |
258 | .in_fds_offset = offsetof(struct run_as_data, u.unlink.dirfd), | |
259 | .in_fd_count = 1, | |
260 | .out_fds_offset = -1, | |
261 | .out_fd_count = 0, | |
262 | .use_cwd_fd = true, | |
263 | }, | |
264 | [RUN_AS_UNLINKAT] = { | |
265 | .in_fds_offset = offsetof(struct run_as_data, u.unlink.dirfd), | |
266 | .in_fd_count = 1, | |
267 | .out_fds_offset = -1, | |
268 | .out_fd_count = 0, | |
269 | .use_cwd_fd = false, | |
270 | }, | |
271 | [RUN_AS_RMDIR_RECURSIVE] = { | |
272 | .in_fds_offset = offsetof(struct run_as_data, u.rmdir.dirfd), | |
273 | .in_fd_count = 1, | |
274 | .out_fds_offset = -1, | |
275 | .out_fd_count = 0, | |
276 | .use_cwd_fd = true, | |
277 | }, | |
278 | [RUN_AS_RMDIRAT_RECURSIVE] = { | |
279 | .in_fds_offset = offsetof(struct run_as_data, u.rmdir.dirfd), | |
280 | .in_fd_count = 1, | |
281 | .out_fds_offset = -1, | |
282 | .out_fd_count = 0, | |
283 | .use_cwd_fd = false, | |
284 | }, | |
285 | [RUN_AS_RMDIR] = { | |
286 | .in_fds_offset = offsetof(struct run_as_data, u.rmdir.dirfd), | |
287 | .in_fd_count = 1, | |
288 | .out_fds_offset = -1, | |
289 | .out_fd_count = 0, | |
290 | .use_cwd_fd = true, | |
291 | }, | |
292 | [RUN_AS_RMDIRAT] = { | |
293 | .in_fds_offset = offsetof(struct run_as_data, u.rmdir.dirfd), | |
294 | .in_fd_count = 1, | |
295 | .out_fds_offset = -1, | |
296 | .out_fd_count = 0, | |
297 | .use_cwd_fd = false, | |
298 | }, | |
299 | [RUN_AS_RENAME] = { | |
300 | .in_fds_offset = offsetof(struct run_as_data, u.rename.dirfds), | |
301 | .in_fd_count = 2, | |
302 | .out_fds_offset = -1, | |
303 | .out_fd_count = 0, | |
304 | .use_cwd_fd = true, | |
305 | }, | |
306 | [RUN_AS_RENAMEAT] = { | |
307 | .in_fds_offset = offsetof(struct run_as_data, u.rename.dirfds), | |
308 | .in_fd_count = 2, | |
309 | .out_fds_offset = -1, | |
310 | .out_fd_count = 0, | |
311 | .use_cwd_fd = false, | |
312 | }, | |
313 | [RUN_AS_EXTRACT_ELF_SYMBOL_OFFSET] = { | |
314 | .in_fds_offset = offsetof(struct run_as_data, | |
315 | u.extract_elf_symbol_offset.fd), | |
316 | .in_fd_count = 1, | |
317 | .out_fds_offset = -1, | |
318 | .out_fd_count = 0, | |
319 | .use_cwd_fd = false, | |
320 | }, | |
321 | [RUN_AS_EXTRACT_SDT_PROBE_OFFSETS] = { | |
322 | .in_fds_offset = offsetof(struct run_as_data, | |
323 | u.extract_sdt_probe_offsets.fd), | |
324 | .in_fd_count = 1, | |
325 | .out_fds_offset = -1, | |
326 | .out_fd_count = 0, | |
327 | .use_cwd_fd = false, | |
328 | }, | |
c73f064a JR |
329 | [RUN_AS_GENERATE_FILTER_BYTECODE] = { |
330 | .in_fds_offset = -1, | |
331 | .in_fd_count = 0, | |
332 | .out_fds_offset = -1, | |
333 | .out_fd_count = 0, | |
334 | .use_cwd_fd = false, | |
335 | }, | |
df5b86c8 MD |
336 | }; |
337 | ||
7567352f MD |
338 | struct run_as_worker { |
339 | pid_t pid; /* Worker PID. */ | |
340 | int sockpair[2]; | |
341 | char *procname; | |
342 | }; | |
343 | ||
344 | /* Single global worker per process (for now). */ | |
345 | static struct run_as_worker *global_worker; | |
346 | /* Lock protecting the worker. */ | |
347 | static pthread_mutex_t worker_lock = PTHREAD_MUTEX_INITIALIZER; | |
348 | ||
8f0044bf MD |
349 | #ifdef VALGRIND |
350 | static | |
351 | int use_clone(void) | |
352 | { | |
353 | return 0; | |
354 | } | |
355 | #else | |
356 | static | |
357 | int use_clone(void) | |
358 | { | |
e8fa9fb0 | 359 | return !lttng_secure_getenv("LTTNG_DEBUG_NOCLONE"); |
8f0044bf MD |
360 | } |
361 | #endif | |
362 | ||
60b6c79c MD |
363 | /* |
364 | * Create recursively directory using the FULL path. | |
365 | */ | |
366 | static | |
18710679 | 367 | int _mkdirat_recursive(struct run_as_data *data, struct run_as_ret *ret_value) |
60b6c79c | 368 | { |
60b6c79c | 369 | const char *path; |
60b6c79c | 370 | mode_t mode; |
cbf53d23 | 371 | struct lttng_directory_handle *handle; |
60b6c79c | 372 | |
93bed9fe JG |
373 | path = data->u.mkdir.path; |
374 | mode = data->u.mkdir.mode; | |
60b6c79c | 375 | |
cbf53d23 JG |
376 | handle = lttng_directory_handle_create_from_dirfd(data->u.mkdir.dirfd); |
377 | if (!handle) { | |
378 | ret_value->_errno = errno; | |
379 | ret_value->_error = true; | |
380 | ret_value->u.ret = -1; | |
381 | goto end; | |
382 | } | |
87bbb856 | 383 | /* Ownership of dirfd is transferred to the handle. */ |
93bed9fe | 384 | data->u.mkdir.dirfd = -1; |
d77dded2 | 385 | /* Safe to call as we have transitioned to the requested uid/gid. */ |
cbf53d23 JG |
386 | ret_value->u.ret = lttng_directory_handle_create_subdirectory_recursive( |
387 | handle, path, mode); | |
fe9f7760 | 388 | ret_value->_errno = errno; |
93bed9fe | 389 | ret_value->_error = (ret_value->u.ret) ? true : false; |
cbf53d23 JG |
390 | lttng_directory_handle_put(handle); |
391 | end: | |
93bed9fe | 392 | return ret_value->u.ret; |
60b6c79c MD |
393 | } |
394 | ||
395 | static | |
18710679 | 396 | int _mkdirat(struct run_as_data *data, struct run_as_ret *ret_value) |
60b6c79c | 397 | { |
18710679 JG |
398 | const char *path; |
399 | mode_t mode; | |
cbf53d23 | 400 | struct lttng_directory_handle *handle; |
18710679 | 401 | |
93bed9fe JG |
402 | path = data->u.mkdir.path; |
403 | mode = data->u.mkdir.mode; | |
18710679 | 404 | |
cbf53d23 JG |
405 | handle = lttng_directory_handle_create_from_dirfd(data->u.mkdir.dirfd); |
406 | if (!handle) { | |
407 | ret_value->u.ret = -1; | |
408 | ret_value->_errno = errno; | |
409 | ret_value->_error = true; | |
410 | goto end; | |
411 | } | |
87bbb856 | 412 | /* Ownership of dirfd is transferred to the handle. */ |
93bed9fe | 413 | data->u.mkdir.dirfd = -1; |
18710679 | 414 | /* Safe to call as we have transitioned to the requested uid/gid. */ |
cbf53d23 JG |
415 | ret_value->u.ret = lttng_directory_handle_create_subdirectory( |
416 | handle, path, mode); | |
fe9f7760 | 417 | ret_value->_errno = errno; |
93bed9fe | 418 | ret_value->_error = (ret_value->u.ret) ? true : false; |
cbf53d23 JG |
419 | lttng_directory_handle_put(handle); |
420 | end: | |
93bed9fe | 421 | return ret_value->u.ret; |
7567352f | 422 | } |
7ce36756 | 423 | |
7567352f | 424 | static |
fe9f7760 | 425 | int _open(struct run_as_data *data, struct run_as_ret *ret_value) |
7567352f | 426 | { |
93bed9fe | 427 | int fd; |
cbf53d23 | 428 | struct lttng_directory_handle *handle; |
93bed9fe | 429 | |
cbf53d23 JG |
430 | handle = lttng_directory_handle_create_from_dirfd(data->u.open.dirfd); |
431 | if (!handle) { | |
432 | ret_value->_errno = errno; | |
433 | ret_value->_error = true; | |
434 | ret_value->u.ret = -1; | |
435 | goto end; | |
436 | } | |
93bed9fe JG |
437 | /* Ownership of dirfd is transferred to the handle. */ |
438 | data->u.open.dirfd = -1; | |
439 | ||
cbf53d23 | 440 | fd = lttng_directory_handle_open_file(handle, |
93bed9fe JG |
441 | data->u.open.path, data->u.open.flags, |
442 | data->u.open.mode); | |
443 | if (fd < 0) { | |
444 | ret_value->u.ret = -1; | |
445 | ret_value->u.open.fd = -1; | |
446 | } else { | |
447 | ret_value->u.ret = 0; | |
448 | ret_value->u.open.fd = fd; | |
449 | } | |
450 | ||
fe9f7760 | 451 | ret_value->_errno = errno; |
93bed9fe | 452 | ret_value->_error = fd < 0; |
cbf53d23 JG |
453 | lttng_directory_handle_put(handle); |
454 | end: | |
93bed9fe | 455 | return ret_value->u.ret; |
7567352f MD |
456 | } |
457 | ||
458 | static | |
fe9f7760 | 459 | int _unlink(struct run_as_data *data, struct run_as_ret *ret_value) |
7567352f | 460 | { |
cbf53d23 | 461 | struct lttng_directory_handle *handle; |
93bed9fe | 462 | |
cbf53d23 JG |
463 | handle = lttng_directory_handle_create_from_dirfd(data->u.unlink.dirfd); |
464 | if (!handle) { | |
465 | ret_value->u.ret = -1; | |
466 | ret_value->_errno = errno; | |
467 | ret_value->_error = true; | |
468 | goto end; | |
469 | } | |
93bed9fe JG |
470 | |
471 | /* Ownership of dirfd is transferred to the handle. */ | |
472 | data->u.unlink.dirfd = -1; | |
473 | ||
cbf53d23 | 474 | ret_value->u.ret = lttng_directory_handle_unlink_file(handle, |
93bed9fe JG |
475 | data->u.unlink.path); |
476 | ret_value->_errno = errno; | |
477 | ret_value->_error = (ret_value->u.ret) ? true : false; | |
cbf53d23 JG |
478 | lttng_directory_handle_put(handle); |
479 | end: | |
93bed9fe JG |
480 | return ret_value->u.ret; |
481 | } | |
482 | ||
483 | static | |
484 | int _rmdir(struct run_as_data *data, struct run_as_ret *ret_value) | |
485 | { | |
cbf53d23 | 486 | struct lttng_directory_handle *handle; |
93bed9fe | 487 | |
cbf53d23 JG |
488 | handle = lttng_directory_handle_create_from_dirfd(data->u.rmdir.dirfd); |
489 | if (!handle) { | |
490 | ret_value->u.ret = -1; | |
491 | ret_value->_errno = errno; | |
492 | ret_value->_error = true; | |
493 | goto end; | |
494 | } | |
93bed9fe JG |
495 | |
496 | /* Ownership of dirfd is transferred to the handle. */ | |
497 | data->u.rmdir.dirfd = -1; | |
498 | ||
499 | ret_value->u.ret = lttng_directory_handle_remove_subdirectory( | |
cbf53d23 | 500 | handle, data->u.rmdir.path); |
fe9f7760 | 501 | ret_value->_errno = errno; |
93bed9fe | 502 | ret_value->_error = (ret_value->u.ret) ? true : false; |
cbf53d23 JG |
503 | lttng_directory_handle_put(handle); |
504 | end: | |
93bed9fe | 505 | return ret_value->u.ret; |
60b6c79c MD |
506 | } |
507 | ||
508 | static | |
fe9f7760 | 509 | int _rmdir_recursive(struct run_as_data *data, struct run_as_ret *ret_value) |
60b6c79c | 510 | { |
cbf53d23 | 511 | struct lttng_directory_handle *handle; |
93bed9fe | 512 | |
cbf53d23 JG |
513 | handle = lttng_directory_handle_create_from_dirfd(data->u.rmdir.dirfd); |
514 | if (!handle) { | |
515 | ret_value->u.ret = -1; | |
516 | ret_value->_errno = errno; | |
517 | ret_value->_error = true; | |
518 | goto end; | |
519 | } | |
93bed9fe JG |
520 | |
521 | /* Ownership of dirfd is transferred to the handle. */ | |
522 | data->u.rmdir.dirfd = -1; | |
523 | ||
524 | ret_value->u.ret = lttng_directory_handle_remove_subdirectory_recursive( | |
cbf53d23 | 525 | handle, data->u.rmdir.path, data->u.rmdir.flags); |
fe9f7760 | 526 | ret_value->_errno = errno; |
93bed9fe | 527 | ret_value->_error = (ret_value->u.ret) ? true : false; |
cbf53d23 JG |
528 | lttng_directory_handle_put(handle); |
529 | end: | |
93bed9fe JG |
530 | return ret_value->u.ret; |
531 | } | |
532 | ||
533 | static | |
534 | int _rename(struct run_as_data *data, struct run_as_ret *ret_value) | |
535 | { | |
536 | const char *old_path, *new_path; | |
cbf53d23 | 537 | struct lttng_directory_handle *old_handle = NULL, *new_handle = NULL; |
93bed9fe JG |
538 | |
539 | old_path = data->u.rename.old_path; | |
540 | new_path = data->u.rename.new_path; | |
541 | ||
cbf53d23 | 542 | old_handle = lttng_directory_handle_create_from_dirfd( |
93bed9fe | 543 | data->u.rename.dirfds[0]); |
cbf53d23 JG |
544 | if (!old_handle) { |
545 | ret_value->u.ret = -1; | |
546 | goto end; | |
547 | } | |
548 | new_handle = lttng_directory_handle_create_from_dirfd( | |
93bed9fe | 549 | data->u.rename.dirfds[1]); |
cbf53d23 JG |
550 | if (!new_handle) { |
551 | ret_value->u.ret = -1; | |
552 | goto end; | |
553 | } | |
93bed9fe JG |
554 | |
555 | /* Ownership of dirfds are transferred to the handles. */ | |
556 | data->u.rename.dirfds[0] = data->u.rename.dirfds[1] = -1; | |
557 | ||
558 | /* Safe to call as we have transitioned to the requested uid/gid. */ | |
559 | ret_value->u.ret = lttng_directory_handle_rename( | |
cbf53d23 JG |
560 | old_handle, old_path, new_handle, new_path); |
561 | end: | |
562 | lttng_directory_handle_put(old_handle); | |
563 | lttng_directory_handle_put(new_handle); | |
93bed9fe JG |
564 | ret_value->_errno = errno; |
565 | ret_value->_error = (ret_value->u.ret) ? true : false; | |
93bed9fe | 566 | return ret_value->u.ret; |
7567352f | 567 | } |
df5b86c8 | 568 | |
b1b34226 | 569 | #ifdef HAVE_ELF_H |
241e0a5a FD |
570 | static |
571 | int _extract_elf_symbol_offset(struct run_as_data *data, | |
572 | struct run_as_ret *ret_value) | |
573 | { | |
574 | int ret = 0; | |
65eefd4c | 575 | uint64_t offset; |
241e0a5a | 576 | |
93bed9fe JG |
577 | ret_value->_error = false; |
578 | ret = lttng_elf_get_symbol_offset(data->u.extract_elf_symbol_offset.fd, | |
241e0a5a | 579 | data->u.extract_elf_symbol_offset.function, |
65eefd4c | 580 | &offset); |
241e0a5a FD |
581 | if (ret) { |
582 | DBG("Failed to extract ELF function offset"); | |
583 | ret_value->_error = true; | |
584 | } | |
65eefd4c | 585 | ret_value->u.extract_elf_symbol_offset.offset = offset; |
241e0a5a FD |
586 | |
587 | return ret; | |
588 | } | |
589 | ||
0ef03255 FD |
590 | static |
591 | int _extract_sdt_probe_offsets(struct run_as_data *data, | |
592 | struct run_as_ret *ret_value) | |
593 | { | |
594 | int ret = 0; | |
595 | uint64_t *offsets = NULL; | |
596 | uint32_t num_offset; | |
597 | ||
598 | ret_value->_error = false; | |
599 | ||
600 | /* On success, this call allocates the offsets paramater. */ | |
93bed9fe JG |
601 | ret = lttng_elf_get_sdt_probe_offsets( |
602 | data->u.extract_sdt_probe_offsets.fd, | |
0ef03255 FD |
603 | data->u.extract_sdt_probe_offsets.provider_name, |
604 | data->u.extract_sdt_probe_offsets.probe_name, | |
605 | &offsets, &num_offset); | |
606 | ||
607 | if (ret) { | |
608 | DBG("Failed to extract SDT probe offsets"); | |
609 | ret_value->_error = true; | |
610 | goto end; | |
611 | } | |
612 | ||
b8e2fb80 | 613 | if (num_offset <= 0 || num_offset > LTTNG_KERNEL_ABI_MAX_UPROBE_NUM) { |
0ef03255 FD |
614 | DBG("Wrong number of probes."); |
615 | ret = -1; | |
616 | ret_value->_error = true; | |
617 | goto free_offset; | |
618 | } | |
619 | ||
620 | /* Copy the content of the offsets array to the ret struct. */ | |
621 | memcpy(ret_value->u.extract_sdt_probe_offsets.offsets, | |
622 | offsets, num_offset * sizeof(uint64_t)); | |
623 | ||
624 | ret_value->u.extract_sdt_probe_offsets.num_offset = num_offset; | |
625 | ||
626 | free_offset: | |
627 | free(offsets); | |
628 | end: | |
629 | return ret; | |
630 | } | |
b1b34226 MJ |
631 | #else |
632 | static | |
633 | int _extract_elf_symbol_offset(struct run_as_data *data, | |
634 | struct run_as_ret *ret_value) | |
635 | { | |
636 | ERR("Unimplemented runas command RUN_AS_EXTRACT_ELF_SYMBOL_OFFSET"); | |
637 | return -1; | |
638 | } | |
639 | ||
640 | static | |
641 | int _extract_sdt_probe_offsets(struct run_as_data *data, | |
642 | struct run_as_ret *ret_value) | |
643 | { | |
644 | ERR("Unimplemented runas command RUN_AS_EXTRACT_SDT_PROBE_OFFSETS"); | |
645 | return -1; | |
646 | } | |
647 | #endif | |
241e0a5a | 648 | |
c73f064a JR |
649 | static |
650 | int _generate_filter_bytecode(struct run_as_data *data, | |
651 | struct run_as_ret *ret_value) { | |
652 | int ret = 0; | |
653 | const char *filter_expression = NULL; | |
654 | struct filter_parser_ctx *ctx = NULL; | |
655 | ||
656 | ret_value->_error = false; | |
657 | ||
658 | filter_expression = data->u.generate_filter_bytecode.filter_expression; | |
659 | ||
660 | if (lttng_strnlen(filter_expression, LTTNG_FILTER_MAX_LEN - 1) == LTTNG_FILTER_MAX_LEN - 1) { | |
661 | ret_value->_error = true; | |
662 | ret = -1; | |
663 | goto end; | |
664 | } | |
665 | ||
666 | ret = filter_parser_ctx_create_from_filter_expression(filter_expression, &ctx); | |
667 | if (ret < 0) { | |
668 | ret_value->_error = true; | |
669 | ret = -1; | |
670 | goto end; | |
671 | } | |
672 | ||
673 | DBG("Size of bytecode generated: %u bytes.", | |
674 | bytecode_get_len(&ctx->bytecode->b)); | |
675 | ||
676 | /* Copy the lttng_bytecode_filter object to the return structure. */ | |
677 | memcpy(ret_value->u.generate_filter_bytecode.bytecode, | |
678 | &ctx->bytecode->b, | |
679 | sizeof(ctx->bytecode->b) + | |
680 | bytecode_get_len(&ctx->bytecode->b)); | |
681 | ||
682 | end: | |
683 | if (ctx) { | |
684 | filter_bytecode_free(ctx); | |
685 | filter_ir_free(ctx); | |
686 | filter_parser_ctx_free(ctx); | |
687 | } | |
688 | ||
689 | return ret; | |
690 | } | |
7567352f MD |
691 | static |
692 | run_as_fct run_as_enum_to_fct(enum run_as_cmd cmd) | |
693 | { | |
694 | switch (cmd) { | |
695 | case RUN_AS_MKDIR: | |
18710679 JG |
696 | case RUN_AS_MKDIRAT: |
697 | return _mkdirat; | |
698 | case RUN_AS_MKDIR_RECURSIVE: | |
699 | case RUN_AS_MKDIRAT_RECURSIVE: | |
700 | return _mkdirat_recursive; | |
7567352f | 701 | case RUN_AS_OPEN: |
2912cead | 702 | case RUN_AS_OPENAT: |
7567352f MD |
703 | return _open; |
704 | case RUN_AS_UNLINK: | |
2912cead | 705 | case RUN_AS_UNLINKAT: |
7567352f | 706 | return _unlink; |
93bed9fe JG |
707 | case RUN_AS_RMDIR: |
708 | case RUN_AS_RMDIRAT: | |
709 | return _rmdir; | |
7567352f | 710 | case RUN_AS_RMDIR_RECURSIVE: |
93bed9fe | 711 | case RUN_AS_RMDIRAT_RECURSIVE: |
7567352f | 712 | return _rmdir_recursive; |
93bed9fe JG |
713 | case RUN_AS_RENAME: |
714 | case RUN_AS_RENAMEAT: | |
715 | return _rename; | |
241e0a5a FD |
716 | case RUN_AS_EXTRACT_ELF_SYMBOL_OFFSET: |
717 | return _extract_elf_symbol_offset; | |
0ef03255 FD |
718 | case RUN_AS_EXTRACT_SDT_PROBE_OFFSETS: |
719 | return _extract_sdt_probe_offsets; | |
c73f064a JR |
720 | case RUN_AS_GENERATE_FILTER_BYTECODE: |
721 | return _generate_filter_bytecode; | |
7567352f | 722 | default: |
62a7b8ed | 723 | ERR("Unknown command %d", (int) cmd); |
7567352f MD |
724 | return NULL; |
725 | } | |
60b6c79c MD |
726 | } |
727 | ||
4628484a | 728 | static |
93bed9fe | 729 | int do_send_fds(int sock, const int *fds, unsigned int fd_count) |
4628484a | 730 | { |
7567352f | 731 | ssize_t len; |
93bed9fe JG |
732 | unsigned int i; |
733 | ||
734 | for (i = 0; i < fd_count; i++) { | |
735 | if (fds[i] < 0) { | |
a4c64187 | 736 | DBG("Attempt to send invalid file descriptor (fd = %i)", |
93bed9fe JG |
737 | fds[i]); |
738 | /* Return 0 as this is not a fatal error. */ | |
739 | return 0; | |
740 | } | |
4a76dfd3 | 741 | } |
4628484a | 742 | |
4a76dfd3 | 743 | len = lttcomm_send_fds_unix_sock(sock, fds, fd_count); |
93bed9fe | 744 | return len < 0 ? -1 : 0; |
4628484a MD |
745 | } |
746 | ||
747 | static | |
93bed9fe | 748 | int do_recv_fds(int sock, int *fds, unsigned int fd_count) |
4628484a | 749 | { |
93bed9fe JG |
750 | int ret = 0; |
751 | unsigned int i; | |
7567352f | 752 | ssize_t len; |
4628484a | 753 | |
93bed9fe JG |
754 | len = lttcomm_recv_fds_unix_sock(sock, fds, fd_count); |
755 | if (len == 0) { | |
756 | ret = -1; | |
757 | goto end; | |
da9ee832 | 758 | } else if (len < 0) { |
93bed9fe JG |
759 | PERROR("Failed to receive file descriptors from socket"); |
760 | ret = -1; | |
761 | goto end; | |
ca9eb994 JG |
762 | } |
763 | ||
93bed9fe JG |
764 | for (i = 0; i < fd_count; i++) { |
765 | if (fds[i] < 0) { | |
766 | ERR("Invalid file descriptor received from worker (fd = %i)", fds[i]); | |
767 | /* Return 0 as this is not a fatal error. */ | |
768 | } | |
55cb0d6f | 769 | } |
93bed9fe | 770 | end: |
55cb0d6f | 771 | return ret; |
4628484a MD |
772 | } |
773 | ||
fe9f7760 | 774 | static |
93bed9fe JG |
775 | int send_fds_to_worker(const struct run_as_worker *worker, |
776 | const struct run_as_data *data) | |
fe9f7760 FD |
777 | { |
778 | int ret = 0; | |
93bed9fe | 779 | unsigned int i; |
fe9f7760 | 780 | |
93bed9fe JG |
781 | if (COMMAND_USE_CWD_FD(data) || COMMAND_IN_FD_COUNT(data) == 0) { |
782 | goto end; | |
fe9f7760 FD |
783 | } |
784 | ||
93bed9fe JG |
785 | for (i = 0; i < COMMAND_IN_FD_COUNT(data); i++) { |
786 | if (COMMAND_IN_FDS(data)[i] < 0) { | |
787 | ERR("Refusing to send invalid fd to worker (fd = %i)", | |
788 | COMMAND_IN_FDS(data)[i]); | |
789 | ret = -1; | |
790 | goto end; | |
791 | } | |
55cb0d6f | 792 | } |
ca9eb994 | 793 | |
55cb0d6f | 794 | ret = do_send_fds(worker->sockpair[0], COMMAND_IN_FDS(data), |
93bed9fe | 795 | COMMAND_IN_FD_COUNT(data)); |
fe9f7760 | 796 | if (ret < 0) { |
93bed9fe | 797 | PERROR("Failed to send file descriptor to run-as worker"); |
fe9f7760 | 798 | ret = -1; |
93bed9fe | 799 | goto end; |
fe9f7760 | 800 | } |
93bed9fe | 801 | end: |
fe9f7760 FD |
802 | return ret; |
803 | } | |
804 | ||
805 | static | |
93bed9fe JG |
806 | int send_fds_to_master(struct run_as_worker *worker, enum run_as_cmd cmd, |
807 | struct run_as_ret *run_as_ret) | |
fe9f7760 | 808 | { |
93bed9fe JG |
809 | int ret = 0; |
810 | unsigned int i; | |
fe9f7760 | 811 | |
93bed9fe JG |
812 | if (COMMAND_OUT_FD_COUNT(cmd) == 0) { |
813 | goto end; | |
fe9f7760 FD |
814 | } |
815 | ||
93bed9fe JG |
816 | ret = do_send_fds(worker->sockpair[1], COMMAND_OUT_FDS(cmd, run_as_ret), |
817 | COMMAND_OUT_FD_COUNT(cmd)); | |
fe9f7760 | 818 | if (ret < 0) { |
93bed9fe JG |
819 | PERROR("Failed to send file descriptor to master process"); |
820 | goto end; | |
fe9f7760 FD |
821 | } |
822 | ||
93bed9fe | 823 | for (i = 0; i < COMMAND_OUT_FD_COUNT(cmd); i++) { |
a4c64187 FD |
824 | int fd = COMMAND_OUT_FDS(cmd, run_as_ret)[i]; |
825 | if (fd >= 0) { | |
826 | int ret_close = close(fd); | |
827 | ||
828 | if (ret_close < 0) { | |
829 | PERROR("Failed to close result file descriptor (fd = %i)", | |
830 | fd); | |
831 | } | |
93bed9fe JG |
832 | } |
833 | } | |
834 | end: | |
fe9f7760 FD |
835 | return ret; |
836 | } | |
837 | ||
838 | static | |
93bed9fe JG |
839 | int recv_fds_from_worker(const struct run_as_worker *worker, enum run_as_cmd cmd, |
840 | struct run_as_ret *run_as_ret) | |
fe9f7760 FD |
841 | { |
842 | int ret = 0; | |
843 | ||
93bed9fe JG |
844 | if (COMMAND_OUT_FD_COUNT(cmd) == 0) { |
845 | goto end; | |
fe9f7760 FD |
846 | } |
847 | ||
93bed9fe JG |
848 | ret = do_recv_fds(worker->sockpair[0], COMMAND_OUT_FDS(cmd, run_as_ret), |
849 | COMMAND_OUT_FD_COUNT(cmd)); | |
fe9f7760 | 850 | if (ret < 0) { |
93bed9fe | 851 | PERROR("Failed to receive file descriptor from run-as worker"); |
fe9f7760 FD |
852 | ret = -1; |
853 | } | |
93bed9fe | 854 | end: |
fe9f7760 FD |
855 | return ret; |
856 | } | |
857 | ||
858 | static | |
93bed9fe | 859 | int recv_fds_from_master(struct run_as_worker *worker, struct run_as_data *data) |
fe9f7760 FD |
860 | { |
861 | int ret = 0; | |
862 | ||
93bed9fe JG |
863 | if (COMMAND_USE_CWD_FD(data)) { |
864 | unsigned int i; | |
865 | ||
866 | for (i = 0; i < COMMAND_IN_FD_COUNT(data); i++) { | |
867 | COMMAND_IN_FDS(data)[i] = AT_FDCWD; | |
868 | } | |
869 | goto end; | |
fe9f7760 FD |
870 | } |
871 | ||
c73f064a JR |
872 | if (COMMAND_IN_FD_COUNT(data) == 0) { |
873 | goto end; | |
874 | } | |
875 | ||
93bed9fe JG |
876 | ret = do_recv_fds(worker->sockpair[1], COMMAND_IN_FDS(data), |
877 | COMMAND_IN_FD_COUNT(data)); | |
fe9f7760 | 878 | if (ret < 0) { |
93bed9fe | 879 | PERROR("Failed to receive file descriptors from master process"); |
fe9f7760 FD |
880 | ret = -1; |
881 | } | |
93bed9fe | 882 | end: |
fe9f7760 FD |
883 | return ret; |
884 | } | |
885 | ||
886 | static | |
93bed9fe | 887 | int cleanup_received_fds(struct run_as_data *data) |
fe9f7760 | 888 | { |
93bed9fe | 889 | int ret = 0, i; |
fe9f7760 | 890 | |
93bed9fe JG |
891 | for (i = 0; i < COMMAND_IN_FD_COUNT(data); i++) { |
892 | if (COMMAND_IN_FDS(data)[i] == -1) { | |
893 | continue; | |
894 | } | |
895 | ret = close(COMMAND_IN_FDS(data)[i]); | |
896 | if (ret) { | |
897 | PERROR("Failed to close file descriptor received fd in run-as worker"); | |
898 | goto end; | |
899 | } | |
fe9f7760 | 900 | } |
93bed9fe | 901 | end: |
fe9f7760 FD |
902 | return ret; |
903 | } | |
0ef03255 | 904 | |
37ccf8ec FD |
905 | static int get_user_infos_from_uid( |
906 | uid_t uid, char **username, gid_t *primary_gid) | |
907 | { | |
908 | int ret; | |
909 | char *buf = NULL; | |
910 | size_t buf_size; | |
911 | struct passwd pwd; | |
912 | struct passwd *result = NULL; | |
913 | ||
914 | /* Fetch the max size for the temporary buffer. */ | |
915 | errno = 0; | |
916 | buf_size = sysconf(_SC_GETPW_R_SIZE_MAX); | |
917 | if (buf_size < 0) { | |
918 | if (errno != 0) { | |
919 | PERROR("Failed to query _SC_GETPW_R_SIZE_MAX"); | |
920 | goto error; | |
921 | } | |
922 | ||
923 | /* Limit is indeterminate. */ | |
924 | WARN("Failed to query _SC_GETPW_R_SIZE_MAX as it is " | |
925 | "indeterminate; falling back to default buffer size"); | |
926 | buf_size = GETPW_BUFFER_FALLBACK_SIZE; | |
927 | } | |
928 | ||
929 | buf = zmalloc(buf_size); | |
930 | if (buf == NULL) { | |
931 | PERROR("Failed to allocate buffer to get password file entries"); | |
932 | goto error; | |
933 | } | |
934 | ||
935 | ret = getpwuid_r(uid, &pwd, buf, buf_size, &result); | |
936 | if (ret < 0) { | |
937 | PERROR("Failed to get user information for user: uid = %d", | |
938 | (int) uid); | |
939 | goto error; | |
940 | } | |
941 | ||
942 | if (result == NULL) { | |
943 | ERR("Failed to find user information in password entries: uid = %d", | |
944 | (int) uid); | |
945 | ret = -1; | |
946 | goto error; | |
947 | } | |
948 | ||
949 | *username = strdup(result->pw_name); | |
950 | if (*username == NULL) { | |
951 | PERROR("Failed to copy user name"); | |
952 | goto error; | |
953 | } | |
954 | ||
955 | *primary_gid = result->pw_gid; | |
956 | ||
957 | end: | |
958 | free(buf); | |
959 | return ret; | |
960 | error: | |
961 | *username = NULL; | |
962 | *primary_gid = -1; | |
963 | ret = -1; | |
964 | goto end; | |
965 | } | |
966 | ||
967 | static int demote_creds( | |
968 | uid_t prev_uid, gid_t prev_gid, uid_t new_uid, gid_t new_gid) | |
969 | { | |
970 | int ret = 0; | |
971 | gid_t primary_gid; | |
972 | char *username = NULL; | |
973 | ||
974 | /* Change the group id. */ | |
975 | if (prev_gid != new_gid) { | |
976 | ret = setegid(new_gid); | |
977 | if (ret < 0) { | |
978 | PERROR("Failed to set effective group id: new_gid = %d", | |
979 | (int) new_gid); | |
980 | goto end; | |
981 | } | |
982 | } | |
983 | ||
984 | /* Change the user id. */ | |
985 | if (prev_uid != new_uid) { | |
986 | ret = get_user_infos_from_uid(new_uid, &username, &primary_gid); | |
987 | if (ret < 0) { | |
988 | goto end; | |
989 | } | |
990 | ||
991 | /* | |
992 | * Initialize the supplementary group access list. | |
993 | * | |
994 | * This is needed to handle cases where the supplementary groups | |
995 | * of the user the process is demoting-to would give it access | |
996 | * to a given file/folder, but not it's primary group. | |
997 | * | |
998 | * e.g | |
999 | * username: User1 | |
1000 | * Primary Group: User1 | |
1001 | * Secondary group: Disk, Network | |
1002 | * | |
1003 | * mkdir inside the following directory must work since User1 | |
1004 | * is part of the Network group. | |
1005 | * | |
1006 | * drwxrwx--- 2 root Network 4096 Jul 23 17:17 /tmp/my_folder/ | |
1007 | * | |
1008 | * | |
1009 | * The order of the following initgroups and seteuid calls is | |
1010 | * important here; | |
1011 | * Only a root process or one with CAP_SETGID capability can | |
1012 | * call the the initgroups() function. We must initialize the | |
1013 | * supplementary groups before we change the effective | |
1014 | * UID to a less-privileged user. | |
1015 | */ | |
1016 | ret = initgroups(username, primary_gid); | |
1017 | if (ret < 0) { | |
1018 | PERROR("Failed to init the supplementary group access list: " | |
1019 | "username = `%s`, primary gid = %d", username, | |
1020 | (int) primary_gid); | |
1021 | goto end; | |
1022 | } | |
1023 | ||
1024 | ret = seteuid(new_uid); | |
1025 | if (ret < 0) { | |
1026 | PERROR("Failed to set effective user id: new_uid = %d", | |
1027 | (int) new_uid); | |
1028 | goto end; | |
1029 | } | |
1030 | } | |
1031 | end: | |
1032 | free(username); | |
1033 | return ret; | |
1034 | } | |
1035 | ||
1036 | static int promote_creds( | |
1037 | uid_t prev_uid, gid_t prev_gid, uid_t new_uid, gid_t new_gid) | |
1038 | { | |
1039 | int ret = 0; | |
1040 | gid_t primary_gid; | |
1041 | char *username = NULL; | |
1042 | ||
1043 | /* Change the group id. */ | |
1044 | if (prev_gid != new_gid) { | |
1045 | ret = setegid(new_gid); | |
1046 | if (ret < 0) { | |
1047 | PERROR("Failed to set effective group id: new_gid = %d", | |
1048 | (int) new_gid); | |
1049 | goto end; | |
1050 | } | |
1051 | } | |
1052 | ||
1053 | /* Change the user id. */ | |
1054 | if (prev_uid != new_uid) { | |
1055 | ret = get_user_infos_from_uid(new_uid, &username, &primary_gid); | |
1056 | if (ret < 0) { | |
1057 | goto end; | |
1058 | } | |
1059 | ||
1060 | /* | |
1061 | * seteuid call must be done before the initgroups call because | |
1062 | * we need to be privileged (CAP_SETGID) to call initgroups(). | |
1063 | */ | |
1064 | ret = seteuid(new_uid); | |
1065 | if (ret < 0) { | |
1066 | PERROR("Failed to set effective user id: new_uid = %d", | |
1067 | (int) new_uid); | |
1068 | goto end; | |
1069 | } | |
1070 | ||
1071 | /* | |
1072 | * Initialize the supplementary group access list. | |
1073 | * | |
1074 | * There is a possibility the groups we set in the following | |
1075 | * initgroups() call are not exactly the same as the ones we | |
1076 | * had when we originally demoted. This can happen if the | |
1077 | * /etc/group file is modified after the runas process is | |
1078 | * forked. This is very unlikely. | |
1079 | */ | |
1080 | ret = initgroups(username, primary_gid); | |
1081 | if (ret < 0) { | |
1082 | PERROR("Failed to init the supplementary group access " | |
1083 | "list: username = `%s`, primary gid = %d", | |
1084 | username, (int) primary_gid) | |
1085 | goto end; | |
1086 | } | |
1087 | } | |
1088 | end: | |
1089 | free(username); | |
1090 | return ret; | |
1091 | } | |
1092 | ||
7567352f MD |
1093 | /* |
1094 | * Return < 0 on error, 0 if OK, 1 on hangup. | |
1095 | */ | |
c2b75c49 | 1096 | static |
7567352f | 1097 | int handle_one_cmd(struct run_as_worker *worker) |
c2b75c49 | 1098 | { |
37ccf8ec | 1099 | int ret = 0, promote_ret; |
55cb0d6f JG |
1100 | struct run_as_data data = {}; |
1101 | ssize_t readlen, writelen; | |
1102 | struct run_as_ret sendret = {}; | |
1103 | run_as_fct cmd; | |
37ccf8ec FD |
1104 | uid_t prev_ruid; |
1105 | gid_t prev_rgid; | |
7567352f | 1106 | |
fe9f7760 FD |
1107 | /* |
1108 | * Stage 1: Receive run_as_data struct from the master. | |
1109 | * The structure contains the command type and all the parameters needed for | |
1110 | * its execution | |
1111 | */ | |
7567352f MD |
1112 | readlen = lttcomm_recv_unix_sock(worker->sockpair[1], &data, |
1113 | sizeof(data)); | |
1114 | if (readlen == 0) { | |
1115 | /* hang up */ | |
1116 | ret = 1; | |
1117 | goto end; | |
1118 | } | |
1119 | if (readlen < sizeof(data)) { | |
1120 | PERROR("lttcomm_recv_unix_sock error"); | |
1121 | ret = -1; | |
1122 | goto end; | |
1123 | } | |
c2b75c49 | 1124 | |
7567352f MD |
1125 | cmd = run_as_enum_to_fct(data.cmd); |
1126 | if (!cmd) { | |
1127 | ret = -1; | |
1128 | goto end; | |
1129 | } | |
1130 | ||
fe9f7760 FD |
1131 | /* |
1132 | * Stage 2: Receive file descriptor from master. | |
1133 | * Some commands need a file descriptor as input so if it's needed we | |
1134 | * receive the fd using the Unix socket. | |
1135 | */ | |
93bed9fe | 1136 | ret = recv_fds_from_master(worker, &data); |
fe9f7760 FD |
1137 | if (ret < 0) { |
1138 | PERROR("recv_fd_from_master error"); | |
1139 | ret = -1; | |
1140 | goto end; | |
1141 | } | |
1142 | ||
37ccf8ec FD |
1143 | prev_ruid = getuid(); |
1144 | prev_rgid = getgid(); | |
1145 | ||
1146 | ret = demote_creds(prev_ruid, prev_rgid, data.uid, data.gid); | |
1147 | if (ret < 0) { | |
1148 | goto write_return; | |
c2b75c49 | 1149 | } |
fe9f7760 | 1150 | |
c2b75c49 MD |
1151 | /* |
1152 | * Also set umask to 0 for mkdir executable bit. | |
1153 | */ | |
1154 | umask(0); | |
fe9f7760 FD |
1155 | |
1156 | /* | |
1157 | * Stage 3: Execute the command | |
1158 | */ | |
1159 | ret = (*cmd)(&data, &sendret); | |
1160 | if (ret < 0) { | |
1161 | DBG("Execution of command returned an error"); | |
1162 | } | |
6d73c4ef MD |
1163 | |
1164 | write_return: | |
93bed9fe | 1165 | ret = cleanup_received_fds(&data); |
fe9f7760 FD |
1166 | if (ret < 0) { |
1167 | ERR("Error cleaning up FD"); | |
37ccf8ec | 1168 | goto promote_back; |
fe9f7760 FD |
1169 | } |
1170 | ||
1171 | /* | |
1172 | * Stage 4: Send run_as_ret structure to the master. | |
1173 | * This structure contain the return value of the command and the errno. | |
1174 | */ | |
7567352f MD |
1175 | writelen = lttcomm_send_unix_sock(worker->sockpair[1], &sendret, |
1176 | sizeof(sendret)); | |
6cd525e8 | 1177 | if (writelen < sizeof(sendret)) { |
7567352f MD |
1178 | PERROR("lttcomm_send_unix_sock error"); |
1179 | ret = -1; | |
37ccf8ec | 1180 | goto promote_back; |
7567352f | 1181 | } |
fe9f7760 FD |
1182 | |
1183 | /* | |
93bed9fe | 1184 | * Stage 5: Send resulting file descriptors to the master. |
fe9f7760 | 1185 | */ |
93bed9fe | 1186 | ret = send_fds_to_master(worker, data.cmd, &sendret); |
fe9f7760 FD |
1187 | if (ret < 0) { |
1188 | DBG("Sending FD to master returned an error"); | |
7567352f | 1189 | } |
fe9f7760 | 1190 | |
7567352f | 1191 | ret = 0; |
37ccf8ec FD |
1192 | |
1193 | promote_back: | |
1194 | /* Return to previous uid/gid. */ | |
1195 | promote_ret = promote_creds(data.uid, data.gid, prev_ruid, prev_rgid); | |
1196 | if (promote_ret < 0) { | |
1197 | ERR("Failed to promote back to the initial credentials"); | |
1198 | } | |
1199 | ||
7567352f MD |
1200 | end: |
1201 | return ret; | |
1202 | } | |
1203 | ||
1204 | static | |
1205 | int run_as_worker(struct run_as_worker *worker) | |
1206 | { | |
1207 | int ret; | |
1208 | ssize_t writelen; | |
1209 | struct run_as_ret sendret; | |
1210 | size_t proc_orig_len; | |
1211 | ||
1212 | /* | |
1213 | * Initialize worker. Set a different process cmdline. | |
1214 | */ | |
1215 | proc_orig_len = strlen(worker->procname); | |
1216 | memset(worker->procname, 0, proc_orig_len); | |
1217 | strncpy(worker->procname, DEFAULT_RUN_AS_WORKER_NAME, proc_orig_len); | |
1218 | ||
cb8d0d24 | 1219 | ret = lttng_thread_setname(DEFAULT_RUN_AS_WORKER_NAME); |
e1055edb | 1220 | if (ret && ret != -ENOSYS) { |
b8090274 | 1221 | /* Don't fail as this is not essential. */ |
cb8d0d24 | 1222 | DBG("Failed to set pthread name attribute"); |
6cd525e8 | 1223 | } |
7567352f | 1224 | |
fe9f7760 FD |
1225 | memset(&sendret, 0, sizeof(sendret)); |
1226 | ||
7567352f MD |
1227 | writelen = lttcomm_send_unix_sock(worker->sockpair[1], &sendret, |
1228 | sizeof(sendret)); | |
1229 | if (writelen < sizeof(sendret)) { | |
1230 | PERROR("lttcomm_send_unix_sock error"); | |
1231 | ret = EXIT_FAILURE; | |
1232 | goto end; | |
1233 | } | |
1234 | ||
1235 | for (;;) { | |
1236 | ret = handle_one_cmd(worker); | |
1237 | if (ret < 0) { | |
1238 | ret = EXIT_FAILURE; | |
1239 | goto end; | |
1240 | } else if (ret > 0) { | |
1241 | break; | |
1242 | } else { | |
1243 | continue; /* Next command. */ | |
1244 | } | |
1245 | } | |
1246 | ret = EXIT_SUCCESS; | |
1247 | end: | |
1248 | return ret; | |
c2b75c49 MD |
1249 | } |
1250 | ||
60b6c79c | 1251 | static |
7567352f MD |
1252 | int run_as_cmd(struct run_as_worker *worker, |
1253 | enum run_as_cmd cmd, | |
1254 | struct run_as_data *data, | |
fe9f7760 | 1255 | struct run_as_ret *ret_value, |
7567352f | 1256 | uid_t uid, gid_t gid) |
60b6c79c | 1257 | { |
fe9f7760 | 1258 | int ret = 0; |
7567352f | 1259 | ssize_t readlen, writelen; |
60b6c79c MD |
1260 | |
1261 | /* | |
1262 | * If we are non-root, we can only deal with our own uid. | |
1263 | */ | |
1264 | if (geteuid() != 0) { | |
1265 | if (uid != geteuid()) { | |
fe9f7760 FD |
1266 | ret = -1; |
1267 | ret_value->_errno = EPERM; | |
60b6c79c | 1268 | ERR("Client (%d)/Server (%d) UID mismatch (and sessiond is not root)", |
08797918 | 1269 | (int) uid, (int) geteuid()); |
df5b86c8 | 1270 | goto end; |
60b6c79c | 1271 | } |
60b6c79c MD |
1272 | } |
1273 | ||
7567352f MD |
1274 | data->cmd = cmd; |
1275 | data->uid = uid; | |
1276 | data->gid = gid; | |
1277 | ||
fe9f7760 FD |
1278 | /* |
1279 | * Stage 1: Send the run_as_data struct to the worker process | |
1280 | */ | |
7567352f MD |
1281 | writelen = lttcomm_send_unix_sock(worker->sockpair[0], data, |
1282 | sizeof(*data)); | |
1283 | if (writelen < sizeof(*data)) { | |
1284 | PERROR("Error writing message to run_as"); | |
fe9f7760 FD |
1285 | ret = -1; |
1286 | ret_value->_errno = EIO; | |
60b6c79c | 1287 | goto end; |
c2b75c49 | 1288 | } |
7567352f | 1289 | |
fe9f7760 FD |
1290 | /* |
1291 | * Stage 2: Send file descriptor to the worker process if needed | |
1292 | */ | |
93bed9fe | 1293 | ret = send_fds_to_worker(worker, data); |
fe9f7760 FD |
1294 | if (ret) { |
1295 | PERROR("do_send_fd error"); | |
1296 | ret = -1; | |
1297 | ret_value->_errno = EIO; | |
1298 | goto end; | |
1299 | } | |
1300 | ||
1301 | /* | |
1302 | * Stage 3: Wait for the execution of the command | |
1303 | */ | |
1304 | ||
1305 | /* | |
1306 | * Stage 4: Receive the run_as_ret struct containing the return value and | |
1307 | * errno | |
1308 | */ | |
1309 | readlen = lttcomm_recv_unix_sock(worker->sockpair[0], ret_value, | |
1310 | sizeof(*ret_value)); | |
da9ee832 JG |
1311 | if (!readlen) { |
1312 | ERR("Run-as worker has hung-up during run_as_cmd"); | |
fe9f7760 FD |
1313 | ret = -1; |
1314 | ret_value->_errno = EIO; | |
da9ee832 | 1315 | goto end; |
fe9f7760 | 1316 | } else if (readlen < sizeof(*ret_value)) { |
7567352f | 1317 | PERROR("Error reading response from run_as"); |
fe9f7760 FD |
1318 | ret = -1; |
1319 | ret_value->_errno = errno; | |
033b58a7 | 1320 | goto end; |
6cd525e8 | 1321 | } |
fe9f7760 | 1322 | |
ca9eb994 JG |
1323 | if (ret_value->_error) { |
1324 | /* Skip stage 5 on error as there will be no fd to receive. */ | |
1325 | goto end; | |
1326 | } | |
1327 | ||
fe9f7760 FD |
1328 | /* |
1329 | * Stage 5: Receive file descriptor if needed | |
1330 | */ | |
93bed9fe | 1331 | ret = recv_fds_from_worker(worker, cmd, ret_value); |
fe9f7760 FD |
1332 | if (ret < 0) { |
1333 | ERR("Error receiving fd"); | |
1334 | ret = -1; | |
1335 | ret_value->_errno = EIO; | |
4c462e79 | 1336 | } |
7567352f | 1337 | |
60b6c79c | 1338 | end: |
fe9f7760 | 1339 | return ret; |
60b6c79c MD |
1340 | } |
1341 | ||
2d85a600 | 1342 | /* |
7567352f | 1343 | * This is for debugging ONLY and should not be considered secure. |
2d85a600 MD |
1344 | */ |
1345 | static | |
fe9f7760 FD |
1346 | int run_as_noworker(enum run_as_cmd cmd, |
1347 | struct run_as_data *data, struct run_as_ret *ret_value, | |
1348 | uid_t uid, gid_t gid) | |
2d85a600 | 1349 | { |
df5b86c8 | 1350 | int ret, saved_errno; |
5b73926f | 1351 | mode_t old_mask; |
7567352f | 1352 | run_as_fct fct; |
5b73926f | 1353 | |
7567352f MD |
1354 | fct = run_as_enum_to_fct(cmd); |
1355 | if (!fct) { | |
1356 | errno = -ENOSYS; | |
1357 | ret = -1; | |
1358 | goto end; | |
1359 | } | |
5b73926f | 1360 | old_mask = umask(0); |
fe9f7760 FD |
1361 | ret = fct(data, ret_value); |
1362 | saved_errno = ret_value->_errno; | |
5b73926f | 1363 | umask(old_mask); |
df5b86c8 | 1364 | errno = saved_errno; |
7567352f | 1365 | end: |
5b73926f | 1366 | return ret; |
2d85a600 MD |
1367 | } |
1368 | ||
8fec83ea JG |
1369 | static |
1370 | int reset_sighandler(void) | |
1371 | { | |
1372 | int sig; | |
1373 | ||
1374 | DBG("Resetting run_as worker signal handlers to default"); | |
1375 | for (sig = 1; sig <= 31; sig++) { | |
1376 | (void) signal(sig, SIG_DFL); | |
1377 | } | |
1378 | return 0; | |
1379 | } | |
1380 | ||
1381 | static | |
1382 | void worker_sighandler(int sig) | |
1383 | { | |
1384 | const char *signame; | |
1385 | ||
1386 | /* | |
1387 | * The worker will inherit its parent's signals since they are part of | |
1388 | * the same process group. However, in the case of SIGINT and SIGTERM, | |
1389 | * we want to give the worker a chance to teardown gracefully when its | |
1390 | * parent closes the command socket. | |
1391 | */ | |
1392 | switch (sig) { | |
1393 | case SIGINT: | |
1394 | signame = "SIGINT"; | |
1395 | break; | |
1396 | case SIGTERM: | |
1397 | signame = "SIGTERM"; | |
1398 | break; | |
1399 | default: | |
1400 | signame = NULL; | |
1401 | } | |
1402 | ||
1403 | if (signame) { | |
1404 | DBG("run_as worker received signal %s", signame); | |
1405 | } else { | |
1406 | DBG("run_as_worker received signal %d", sig); | |
1407 | } | |
1408 | } | |
1409 | ||
1410 | static | |
1411 | int set_worker_sighandlers(void) | |
1412 | { | |
1413 | int ret = 0; | |
1414 | sigset_t sigset; | |
1415 | struct sigaction sa; | |
1416 | ||
1417 | if ((ret = sigemptyset(&sigset)) < 0) { | |
1418 | PERROR("sigemptyset"); | |
1419 | goto end; | |
1420 | } | |
1421 | ||
1422 | sa.sa_handler = worker_sighandler; | |
1423 | sa.sa_mask = sigset; | |
1424 | sa.sa_flags = 0; | |
1425 | if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) { | |
1426 | PERROR("sigaction SIGINT"); | |
1427 | goto end; | |
1428 | } | |
1429 | ||
1430 | if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) { | |
1431 | PERROR("sigaction SIGTERM"); | |
1432 | goto end; | |
1433 | } | |
1434 | ||
1435 | DBG("run_as signal handler set for SIGTERM and SIGINT"); | |
1436 | end: | |
1437 | return ret; | |
1438 | } | |
1439 | ||
1440 | static | |
929f71ec JG |
1441 | int run_as_create_worker_no_lock(const char *procname, |
1442 | post_fork_cleanup_cb clean_up_func, | |
1443 | void *clean_up_user_data) | |
8fec83ea JG |
1444 | { |
1445 | pid_t pid; | |
1446 | int i, ret = 0; | |
1447 | ssize_t readlen; | |
1448 | struct run_as_ret recvret; | |
1449 | struct run_as_worker *worker; | |
1450 | ||
1451 | assert(!global_worker); | |
1452 | if (!use_clone()) { | |
1453 | /* | |
1454 | * Don't initialize a worker, all run_as tasks will be performed | |
1455 | * in the current process. | |
1456 | */ | |
1457 | ret = 0; | |
1458 | goto end; | |
1459 | } | |
1460 | worker = zmalloc(sizeof(*worker)); | |
1461 | if (!worker) { | |
1462 | ret = -ENOMEM; | |
1463 | goto end; | |
1464 | } | |
1465 | worker->procname = strdup(procname); | |
1466 | if (!worker->procname) { | |
1467 | ret = -ENOMEM; | |
8c96eded | 1468 | goto error_procname_alloc; |
8fec83ea JG |
1469 | } |
1470 | /* Create unix socket. */ | |
1471 | if (lttcomm_create_anon_unix_socketpair(worker->sockpair) < 0) { | |
1472 | ret = -1; | |
1473 | goto error_sock; | |
1474 | } | |
1475 | ||
1476 | /* Fork worker. */ | |
1477 | pid = fork(); | |
1478 | if (pid < 0) { | |
1479 | PERROR("fork"); | |
1480 | ret = -1; | |
1481 | goto error_fork; | |
1482 | } else if (pid == 0) { | |
1483 | /* Child */ | |
1484 | ||
1485 | reset_sighandler(); | |
1486 | ||
1487 | set_worker_sighandlers(); | |
c989e0d4 FD |
1488 | |
1489 | logger_set_thread_name("Run-as worker", true); | |
1490 | ||
929f71ec JG |
1491 | if (clean_up_func) { |
1492 | if (clean_up_func(clean_up_user_data) < 0) { | |
1493 | ERR("Run-as post-fork clean-up failed, exiting."); | |
1494 | exit(EXIT_FAILURE); | |
1495 | } | |
1496 | } | |
8fec83ea JG |
1497 | |
1498 | /* Just close, no shutdown. */ | |
1499 | if (close(worker->sockpair[0])) { | |
1500 | PERROR("close"); | |
1501 | exit(EXIT_FAILURE); | |
1502 | } | |
1503 | ||
1504 | /* | |
1505 | * Close all FDs aside from STDIN, STDOUT, STDERR and sockpair[1] | |
1506 | * Sockpair[1] is used as a control channel with the master | |
1507 | */ | |
1508 | for (i = 3; i < sysconf(_SC_OPEN_MAX); i++) { | |
1509 | if (i != worker->sockpair[1]) { | |
1510 | (void) close(i); | |
1511 | } | |
1512 | } | |
1513 | ||
1514 | worker->sockpair[0] = -1; | |
1515 | ret = run_as_worker(worker); | |
1516 | if (lttcomm_close_unix_sock(worker->sockpair[1])) { | |
1517 | PERROR("close"); | |
1518 | ret = -1; | |
1519 | } | |
1520 | worker->sockpair[1] = -1; | |
55cb0d6f | 1521 | free(worker->procname); |
340cf672 | 1522 | free(worker); |
8fec83ea JG |
1523 | LOG(ret ? PRINT_ERR : PRINT_DBG, "run_as worker exiting (ret = %d)", ret); |
1524 | exit(ret ? EXIT_FAILURE : EXIT_SUCCESS); | |
1525 | } else { | |
1526 | /* Parent */ | |
1527 | ||
1528 | /* Just close, no shutdown. */ | |
1529 | if (close(worker->sockpair[1])) { | |
1530 | PERROR("close"); | |
1531 | ret = -1; | |
1532 | goto error_fork; | |
1533 | } | |
1534 | worker->sockpair[1] = -1; | |
1535 | worker->pid = pid; | |
1536 | /* Wait for worker to become ready. */ | |
1537 | readlen = lttcomm_recv_unix_sock(worker->sockpair[0], | |
1538 | &recvret, sizeof(recvret)); | |
1539 | if (readlen < sizeof(recvret)) { | |
1540 | ERR("readlen: %zd", readlen); | |
1541 | PERROR("Error reading response from run_as at creation"); | |
1542 | ret = -1; | |
1543 | goto error_fork; | |
1544 | } | |
1545 | global_worker = worker; | |
1546 | } | |
1547 | end: | |
1548 | return ret; | |
1549 | ||
1550 | /* Error handling. */ | |
1551 | error_fork: | |
1552 | for (i = 0; i < 2; i++) { | |
1553 | if (worker->sockpair[i] < 0) { | |
1554 | continue; | |
1555 | } | |
1556 | if (lttcomm_close_unix_sock(worker->sockpair[i])) { | |
1557 | PERROR("close"); | |
1558 | } | |
1559 | worker->sockpair[i] = -1; | |
1560 | } | |
1561 | error_sock: | |
8c96eded FD |
1562 | free(worker->procname); |
1563 | error_procname_alloc: | |
8fec83ea JG |
1564 | free(worker); |
1565 | return ret; | |
1566 | } | |
1567 | ||
a01c682b JR |
1568 | static |
1569 | void run_as_destroy_worker_no_lock(void) | |
1570 | { | |
1571 | struct run_as_worker *worker = global_worker; | |
1572 | ||
1573 | DBG("Destroying run_as worker"); | |
1574 | if (!worker) { | |
1575 | return; | |
1576 | } | |
1577 | /* Close unix socket */ | |
1578 | DBG("Closing run_as worker socket"); | |
1579 | if (lttcomm_close_unix_sock(worker->sockpair[0])) { | |
1580 | PERROR("close"); | |
1581 | } | |
1582 | worker->sockpair[0] = -1; | |
1583 | /* Wait for worker. */ | |
1584 | for (;;) { | |
1585 | int status; | |
1586 | pid_t wait_ret; | |
1587 | ||
1588 | wait_ret = waitpid(worker->pid, &status, 0); | |
1589 | if (wait_ret < 0) { | |
1590 | if (errno == EINTR) { | |
1591 | continue; | |
1592 | } | |
1593 | PERROR("waitpid"); | |
1594 | break; | |
1595 | } | |
1596 | ||
1597 | if (WIFEXITED(status)) { | |
1598 | LOG(WEXITSTATUS(status) == 0 ? PRINT_DBG : PRINT_ERR, | |
1599 | DEFAULT_RUN_AS_WORKER_NAME " terminated with status code %d", | |
55cb0d6f | 1600 | WEXITSTATUS(status)); |
a01c682b JR |
1601 | break; |
1602 | } else if (WIFSIGNALED(status)) { | |
1603 | ERR(DEFAULT_RUN_AS_WORKER_NAME " was killed by signal %d", | |
1604 | WTERMSIG(status)); | |
1605 | break; | |
1606 | } | |
1607 | } | |
1608 | free(worker->procname); | |
1609 | free(worker); | |
1610 | global_worker = NULL; | |
1611 | } | |
1612 | ||
2d85a600 | 1613 | static |
fe9f7760 | 1614 | int run_as_restart_worker(struct run_as_worker *worker) |
2d85a600 | 1615 | { |
fe9f7760 FD |
1616 | int ret = 0; |
1617 | char *procname = NULL; | |
1618 | ||
1619 | procname = worker->procname; | |
1620 | ||
1621 | /* Close socket to run_as worker process and clean up the zombie process */ | |
a01c682b | 1622 | run_as_destroy_worker_no_lock(); |
fe9f7760 FD |
1623 | |
1624 | /* Create a new run_as worker process*/ | |
929f71ec | 1625 | ret = run_as_create_worker_no_lock(procname, NULL, NULL); |
fe9f7760 FD |
1626 | if (ret < 0 ) { |
1627 | ERR("Restarting the worker process failed"); | |
1628 | ret = -1; | |
1629 | goto err; | |
1630 | } | |
1631 | err: | |
1632 | return ret; | |
1633 | } | |
1634 | ||
1635 | static | |
1636 | int run_as(enum run_as_cmd cmd, struct run_as_data *data, | |
1637 | struct run_as_ret *ret_value, uid_t uid, gid_t gid) | |
1638 | { | |
1639 | int ret, saved_errno; | |
7567352f | 1640 | |
8fec83ea | 1641 | pthread_mutex_lock(&worker_lock); |
749b7a0c | 1642 | if (use_clone()) { |
7567352f | 1643 | DBG("Using run_as worker"); |
8fec83ea | 1644 | |
749b7a0c | 1645 | assert(global_worker); |
749b7a0c | 1646 | |
fe9f7760 FD |
1647 | ret = run_as_cmd(global_worker, cmd, data, ret_value, uid, gid); |
1648 | saved_errno = ret_value->_errno; | |
1649 | ||
fe9f7760 FD |
1650 | /* |
1651 | * If the worker thread crashed the errno is set to EIO. we log | |
1652 | * the error and start a new worker process. | |
1653 | */ | |
1654 | if (ret == -1 && saved_errno == EIO) { | |
1655 | DBG("Socket closed unexpectedly... " | |
1656 | "Restarting the worker process"); | |
1657 | ret = run_as_restart_worker(global_worker); | |
fe9f7760 FD |
1658 | if (ret == -1) { |
1659 | ERR("Failed to restart worker process."); | |
1660 | goto err; | |
1661 | } | |
1662 | } | |
2d85a600 | 1663 | } else { |
7567352f | 1664 | DBG("Using run_as without worker"); |
fe9f7760 | 1665 | ret = run_as_noworker(cmd, data, ret_value, uid, gid); |
2d85a600 | 1666 | } |
fe9f7760 | 1667 | err: |
8fec83ea | 1668 | pthread_mutex_unlock(&worker_lock); |
7567352f | 1669 | return ret; |
2d85a600 MD |
1670 | } |
1671 | ||
90e535ef | 1672 | LTTNG_HIDDEN |
e11d277b | 1673 | int run_as_mkdir_recursive(const char *path, mode_t mode, uid_t uid, gid_t gid) |
60b6c79c | 1674 | { |
18710679 JG |
1675 | return run_as_mkdirat_recursive(AT_FDCWD, path, mode, uid, gid); |
1676 | } | |
1677 | ||
1678 | LTTNG_HIDDEN | |
1679 | int run_as_mkdirat_recursive(int dirfd, const char *path, mode_t mode, | |
1680 | uid_t uid, gid_t gid) | |
1681 | { | |
1682 | int ret; | |
93bed9fe JG |
1683 | struct run_as_data data = {}; |
1684 | struct run_as_ret run_as_ret = {}; | |
60b6c79c | 1685 | |
18710679 JG |
1686 | DBG3("mkdirat() recursive fd = %d%s, path = %s, mode = %d, uid = %d, gid = %d", |
1687 | dirfd, dirfd == AT_FDCWD ? " (AT_FDCWD)" : "", | |
08797918 | 1688 | path, (int) mode, (int) uid, (int) gid); |
93bed9fe JG |
1689 | ret = lttng_strncpy(data.u.mkdir.path, path, |
1690 | sizeof(data.u.mkdir.path)); | |
18710679 JG |
1691 | if (ret) { |
1692 | ERR("Failed to copy path argument of mkdirat recursive command"); | |
1693 | goto error; | |
1694 | } | |
93bed9fe JG |
1695 | data.u.mkdir.path[sizeof(data.u.mkdir.path) - 1] = '\0'; |
1696 | data.u.mkdir.mode = mode; | |
1697 | data.u.mkdir.dirfd = dirfd; | |
18710679 JG |
1698 | run_as(dirfd == AT_FDCWD ? RUN_AS_MKDIR_RECURSIVE : RUN_AS_MKDIRAT_RECURSIVE, |
1699 | &data, &run_as_ret, uid, gid); | |
1700 | errno = run_as_ret._errno; | |
93bed9fe | 1701 | ret = run_as_ret.u.ret; |
18710679 JG |
1702 | error: |
1703 | return ret; | |
60b6c79c MD |
1704 | } |
1705 | ||
90e535ef | 1706 | LTTNG_HIDDEN |
e11d277b | 1707 | int run_as_mkdir(const char *path, mode_t mode, uid_t uid, gid_t gid) |
60b6c79c | 1708 | { |
18710679 JG |
1709 | return run_as_mkdirat(AT_FDCWD, path, mode, uid, gid); |
1710 | } | |
1711 | ||
1712 | LTTNG_HIDDEN | |
1713 | int run_as_mkdirat(int dirfd, const char *path, mode_t mode, | |
1714 | uid_t uid, gid_t gid) | |
1715 | { | |
1716 | int ret; | |
93bed9fe JG |
1717 | struct run_as_data data = {}; |
1718 | struct run_as_ret run_as_ret = {}; | |
fe9f7760 | 1719 | |
18710679 JG |
1720 | DBG3("mkdirat() recursive fd = %d%s, path = %s, mode = %d, uid = %d, gid = %d", |
1721 | dirfd, dirfd == AT_FDCWD ? " (AT_FDCWD)" : "", | |
08797918 | 1722 | path, (int) mode, (int) uid, (int) gid); |
93bed9fe JG |
1723 | ret = lttng_strncpy(data.u.mkdir.path, path, |
1724 | sizeof(data.u.mkdir.path)); | |
18710679 JG |
1725 | if (ret) { |
1726 | ERR("Failed to copy path argument of mkdirat command"); | |
1727 | goto error; | |
1728 | } | |
93bed9fe JG |
1729 | data.u.mkdir.path[sizeof(data.u.mkdir.path) - 1] = '\0'; |
1730 | data.u.mkdir.mode = mode; | |
1731 | data.u.mkdir.dirfd = dirfd; | |
18710679 JG |
1732 | run_as(dirfd == AT_FDCWD ? RUN_AS_MKDIR : RUN_AS_MKDIRAT, |
1733 | &data, &run_as_ret, uid, gid); | |
1734 | errno = run_as_ret._errno; | |
93bed9fe | 1735 | ret = run_as_ret.u.ret; |
18710679 JG |
1736 | error: |
1737 | return ret; | |
60b6c79c MD |
1738 | } |
1739 | ||
90e535ef | 1740 | LTTNG_HIDDEN |
2912cead | 1741 | int run_as_open(const char *path, int flags, mode_t mode, uid_t uid, |
55cb0d6f | 1742 | gid_t gid) |
2912cead JG |
1743 | { |
1744 | return run_as_openat(AT_FDCWD, path, flags, mode, uid, gid); | |
1745 | } | |
1746 | ||
1747 | LTTNG_HIDDEN | |
1748 | int run_as_openat(int dirfd, const char *path, int flags, mode_t mode, | |
1749 | uid_t uid, gid_t gid) | |
60b6c79c | 1750 | { |
93bed9fe | 1751 | int ret; |
55cb0d6f JG |
1752 | struct run_as_data data = {}; |
1753 | struct run_as_ret run_as_ret = {}; | |
fe9f7760 | 1754 | |
2912cead JG |
1755 | DBG3("openat() fd = %d%s, path = %s, flags = %X, mode = %d, uid %d, gid %d", |
1756 | dirfd, dirfd == AT_FDCWD ? " (AT_FDCWD)" : "", | |
08797918 | 1757 | path, flags, (int) mode, (int) uid, (int) gid); |
93bed9fe JG |
1758 | ret = lttng_strncpy(data.u.open.path, path, sizeof(data.u.open.path)); |
1759 | if (ret) { | |
1760 | ERR("Failed to copy path argument of open command"); | |
1761 | goto error; | |
1762 | } | |
7567352f MD |
1763 | data.u.open.flags = flags; |
1764 | data.u.open.mode = mode; | |
93bed9fe | 1765 | data.u.open.dirfd = dirfd; |
2912cead | 1766 | run_as(dirfd == AT_FDCWD ? RUN_AS_OPEN : RUN_AS_OPENAT, |
93bed9fe JG |
1767 | &data, &run_as_ret, uid, gid); |
1768 | errno = run_as_ret._errno; | |
1769 | ret = run_as_ret.u.ret < 0 ? run_as_ret.u.ret : | |
1770 | run_as_ret.u.open.fd; | |
1771 | error: | |
1772 | return ret; | |
60b6c79c | 1773 | } |
4628484a MD |
1774 | |
1775 | LTTNG_HIDDEN | |
1776 | int run_as_unlink(const char *path, uid_t uid, gid_t gid) | |
2912cead JG |
1777 | { |
1778 | return run_as_unlinkat(AT_FDCWD, path, uid, gid); | |
1779 | } | |
1780 | ||
1781 | LTTNG_HIDDEN | |
1782 | int run_as_unlinkat(int dirfd, const char *path, uid_t uid, gid_t gid) | |
4628484a | 1783 | { |
93bed9fe JG |
1784 | int ret; |
1785 | struct run_as_data data = {}; | |
1786 | struct run_as_ret run_as_ret = {}; | |
fe9f7760 | 1787 | |
2912cead JG |
1788 | DBG3("unlinkat() fd = %d%s, path = %s, uid = %d, gid = %d", |
1789 | dirfd, dirfd == AT_FDCWD ? " (AT_FDCWD)" : "", | |
08797918 | 1790 | path, (int) uid, (int) gid); |
93bed9fe JG |
1791 | ret = lttng_strncpy(data.u.unlink.path, path, |
1792 | sizeof(data.u.unlink.path)); | |
1793 | if (ret) { | |
1794 | goto error; | |
1795 | } | |
1796 | data.u.unlink.dirfd = dirfd; | |
1797 | run_as(dirfd == AT_FDCWD ? RUN_AS_UNLINK : RUN_AS_UNLINKAT, &data, | |
1798 | &run_as_ret, uid, gid); | |
1799 | errno = run_as_ret._errno; | |
1800 | ret = run_as_ret.u.ret; | |
1801 | error: | |
1802 | return ret; | |
1803 | } | |
1804 | ||
1805 | LTTNG_HIDDEN | |
1806 | int run_as_rmdir(const char *path, uid_t uid, gid_t gid) | |
1807 | { | |
1808 | return run_as_rmdirat(AT_FDCWD, path, uid, gid); | |
1809 | } | |
1810 | ||
1811 | LTTNG_HIDDEN | |
1812 | int run_as_rmdirat(int dirfd, const char *path, uid_t uid, gid_t gid) | |
1813 | { | |
1814 | int ret; | |
1815 | struct run_as_data data = {}; | |
1816 | struct run_as_ret run_as_ret = {}; | |
1817 | ||
1818 | DBG3("rmdirat() fd = %d%s, path = %s, uid = %d, gid = %d", | |
1819 | dirfd, dirfd == AT_FDCWD ? " (AT_FDCWD)" : "", | |
1820 | path, (int) uid, (int) gid); | |
1821 | ret = lttng_strncpy(data.u.rmdir.path, path, | |
1822 | sizeof(data.u.rmdir.path)); | |
1823 | if (ret) { | |
1824 | goto error; | |
1825 | } | |
1826 | data.u.rmdir.dirfd = dirfd; | |
1827 | run_as(dirfd == AT_FDCWD ? RUN_AS_RMDIR : RUN_AS_RMDIRAT, &data, | |
1828 | &run_as_ret, uid, gid); | |
1829 | errno = run_as_ret._errno; | |
1830 | ret = run_as_ret.u.ret; | |
1831 | error: | |
1832 | return ret; | |
4628484a MD |
1833 | } |
1834 | ||
1835 | LTTNG_HIDDEN | |
f75c5439 | 1836 | int run_as_rmdir_recursive(const char *path, uid_t uid, gid_t gid, int flags) |
4628484a | 1837 | { |
f75c5439 | 1838 | return run_as_rmdirat_recursive(AT_FDCWD, path, uid, gid, flags); |
93bed9fe | 1839 | } |
fe9f7760 | 1840 | |
93bed9fe | 1841 | LTTNG_HIDDEN |
f75c5439 | 1842 | int run_as_rmdirat_recursive(int dirfd, const char *path, uid_t uid, gid_t gid, int flags) |
93bed9fe JG |
1843 | { |
1844 | int ret; | |
1845 | struct run_as_data data = {}; | |
1846 | struct run_as_ret run_as_ret = {}; | |
4628484a | 1847 | |
93bed9fe JG |
1848 | DBG3("rmdirat() recursive fd = %d%s, path = %s, uid = %d, gid = %d", |
1849 | dirfd, dirfd == AT_FDCWD ? " (AT_FDCWD)" : "", | |
08797918 | 1850 | path, (int) uid, (int) gid); |
93bed9fe JG |
1851 | ret = lttng_strncpy(data.u.rmdir.path, path, |
1852 | sizeof(data.u.rmdir.path)); | |
1853 | if (ret) { | |
1854 | goto error; | |
1855 | } | |
1856 | data.u.rmdir.dirfd = dirfd; | |
f75c5439 | 1857 | data.u.rmdir.flags = flags; |
93bed9fe JG |
1858 | run_as(dirfd == AT_FDCWD ? RUN_AS_RMDIR_RECURSIVE : RUN_AS_RMDIRAT_RECURSIVE, |
1859 | &data, &run_as_ret, uid, gid); | |
1860 | errno = run_as_ret._errno; | |
1861 | ret = run_as_ret.u.ret; | |
1862 | error: | |
1863 | return ret; | |
1864 | } | |
1865 | ||
1866 | LTTNG_HIDDEN | |
1867 | int run_as_rename(const char *old, const char *new, uid_t uid, gid_t gid) | |
1868 | { | |
1869 | return run_as_renameat(AT_FDCWD, old, AT_FDCWD, new, uid, gid); | |
1870 | } | |
1871 | ||
1872 | LTTNG_HIDDEN | |
1873 | int run_as_renameat(int old_dirfd, const char *old_name, | |
1874 | int new_dirfd, const char *new_name, uid_t uid, gid_t gid) | |
1875 | { | |
1876 | int ret; | |
1877 | struct run_as_data data = {}; | |
1878 | struct run_as_ret run_as_ret = {}; | |
1879 | ||
1880 | DBG3("renameat() old_dirfd = %d%s, old_name = %s, new_dirfd = %d%s, new_name = %s, uid = %d, gid = %d", | |
1881 | old_dirfd, old_dirfd == AT_FDCWD ? " (AT_FDCWD)" : "", | |
1882 | old_name, | |
1883 | new_dirfd, new_dirfd == AT_FDCWD ? " (AT_FDCWD)" : "", | |
1884 | new_name, (int) uid, (int) gid); | |
1885 | ret = lttng_strncpy(data.u.rename.old_path, old_name, | |
1886 | sizeof(data.u.rename.old_path)); | |
1887 | if (ret) { | |
1888 | goto error; | |
1889 | } | |
1890 | ret = lttng_strncpy(data.u.rename.new_path, new_name, | |
1891 | sizeof(data.u.rename.new_path)); | |
1892 | if (ret) { | |
1893 | goto error; | |
1894 | } | |
1895 | ||
1896 | data.u.rename.dirfds[0] = old_dirfd; | |
1897 | data.u.rename.dirfds[1] = new_dirfd; | |
1898 | run_as(old_dirfd == AT_FDCWD && new_dirfd == AT_FDCWD ? | |
1899 | RUN_AS_RENAME : RUN_AS_RENAMEAT, | |
1900 | &data, &run_as_ret, uid, gid); | |
1901 | errno = run_as_ret._errno; | |
1902 | ret = run_as_ret.u.ret; | |
1903 | error: | |
1904 | return ret; | |
7567352f MD |
1905 | } |
1906 | ||
241e0a5a FD |
1907 | LTTNG_HIDDEN |
1908 | int run_as_extract_elf_symbol_offset(int fd, const char* function, | |
1909 | uid_t uid, gid_t gid, uint64_t *offset) | |
1910 | { | |
93bed9fe JG |
1911 | int ret; |
1912 | struct run_as_data data = {}; | |
55cb0d6f | 1913 | struct run_as_ret run_as_ret = {}; |
f726677b | 1914 | |
241e0a5a | 1915 | DBG3("extract_elf_symbol_offset() on fd=%d and function=%s " |
93bed9fe JG |
1916 | "with for uid %d and gid %d", fd, function, |
1917 | (int) uid, (int) gid); | |
241e0a5a | 1918 | |
93bed9fe | 1919 | data.u.extract_elf_symbol_offset.fd = fd; |
241e0a5a FD |
1920 | |
1921 | strncpy(data.u.extract_elf_symbol_offset.function, function, LTTNG_SYMBOL_NAME_LEN - 1); | |
241e0a5a | 1922 | data.u.extract_elf_symbol_offset.function[LTTNG_SYMBOL_NAME_LEN - 1] = '\0'; |
93bed9fe JG |
1923 | ret = lttng_strncpy(data.u.extract_elf_symbol_offset.function, |
1924 | function, | |
1925 | sizeof(data.u.extract_elf_symbol_offset.function)); | |
1926 | if (ret) { | |
1927 | goto error; | |
1928 | } | |
241e0a5a | 1929 | |
93bed9fe JG |
1930 | run_as(RUN_AS_EXTRACT_ELF_SYMBOL_OFFSET, &data, &run_as_ret, uid, gid); |
1931 | errno = run_as_ret._errno; | |
1932 | if (run_as_ret._error) { | |
1933 | ret = -1; | |
1934 | goto error; | |
241e0a5a FD |
1935 | } |
1936 | ||
93bed9fe JG |
1937 | *offset = run_as_ret.u.extract_elf_symbol_offset.offset; |
1938 | error: | |
1939 | return ret; | |
241e0a5a FD |
1940 | } |
1941 | ||
0ef03255 FD |
1942 | LTTNG_HIDDEN |
1943 | int run_as_extract_sdt_probe_offsets(int fd, const char* provider_name, | |
1944 | const char* probe_name, uid_t uid, gid_t gid, | |
1945 | uint64_t **offsets, uint32_t *num_offset) | |
1946 | { | |
93bed9fe JG |
1947 | int ret; |
1948 | struct run_as_data data = {}; | |
1949 | struct run_as_ret run_as_ret = {}; | |
f726677b | 1950 | |
0ef03255 | 1951 | DBG3("extract_sdt_probe_offsets() on fd=%d, probe_name=%s and " |
93bed9fe JG |
1952 | "provider_name=%s with for uid %d and gid %d", fd, |
1953 | probe_name, provider_name, (int) uid, (int) gid); | |
0ef03255 | 1954 | |
93bed9fe | 1955 | data.u.extract_sdt_probe_offsets.fd = fd; |
0ef03255 | 1956 | |
93bed9fe JG |
1957 | ret = lttng_strncpy(data.u.extract_sdt_probe_offsets.probe_name, probe_name, |
1958 | sizeof(data.u.extract_sdt_probe_offsets.probe_name)); | |
1959 | if (ret) { | |
1960 | goto error; | |
1961 | } | |
1962 | ret = lttng_strncpy(data.u.extract_sdt_probe_offsets.provider_name, | |
1963 | provider_name, | |
1964 | sizeof(data.u.extract_sdt_probe_offsets.provider_name)); | |
1965 | if (ret) { | |
1966 | goto error; | |
0ef03255 FD |
1967 | } |
1968 | ||
93bed9fe JG |
1969 | run_as(RUN_AS_EXTRACT_SDT_PROBE_OFFSETS, &data, &run_as_ret, uid, gid); |
1970 | errno = run_as_ret._errno; | |
1971 | if (run_as_ret._error) { | |
1972 | ret = -1; | |
1973 | goto error; | |
1974 | } | |
0ef03255 | 1975 | |
93bed9fe | 1976 | *num_offset = run_as_ret.u.extract_sdt_probe_offsets.num_offset; |
0ef03255 FD |
1977 | *offsets = zmalloc(*num_offset * sizeof(uint64_t)); |
1978 | if (!*offsets) { | |
93bed9fe JG |
1979 | ret = -ENOMEM; |
1980 | goto error; | |
0ef03255 FD |
1981 | } |
1982 | ||
93bed9fe JG |
1983 | memcpy(*offsets, run_as_ret.u.extract_sdt_probe_offsets.offsets, |
1984 | *num_offset * sizeof(uint64_t)); | |
1985 | error: | |
1986 | return ret; | |
0ef03255 FD |
1987 | } |
1988 | ||
c73f064a JR |
1989 | LTTNG_HIDDEN |
1990 | int run_as_generate_filter_bytecode(const char *filter_expression, | |
58daac01 | 1991 | const struct lttng_credentials *creds, |
2b00d462 | 1992 | struct lttng_bytecode **bytecode) |
c73f064a JR |
1993 | { |
1994 | int ret; | |
1995 | struct run_as_data data = {}; | |
1996 | struct run_as_ret run_as_ret = {}; | |
2b00d462 SM |
1997 | const struct lttng_bytecode *view_bytecode = NULL; |
1998 | struct lttng_bytecode *local_bytecode = NULL; | |
58daac01 JR |
1999 | const uid_t uid = lttng_credentials_get_uid(creds); |
2000 | const gid_t gid = lttng_credentials_get_gid(creds); | |
c73f064a JR |
2001 | |
2002 | DBG3("generate_filter_bytecode() from expression=\"%s\" for uid %d and gid %d", | |
2003 | filter_expression, (int) uid, (int) gid); | |
2004 | ||
2005 | ret = lttng_strncpy(data.u.generate_filter_bytecode.filter_expression, filter_expression, | |
2006 | sizeof(data.u.generate_filter_bytecode.filter_expression)); | |
2007 | if (ret) { | |
2008 | goto error; | |
2009 | } | |
2010 | ||
2011 | run_as(RUN_AS_GENERATE_FILTER_BYTECODE, &data, &run_as_ret, uid, gid); | |
2012 | errno = run_as_ret._errno; | |
2013 | if (run_as_ret._error) { | |
2014 | ret = -1; | |
2015 | goto error; | |
2016 | } | |
2017 | ||
2b00d462 | 2018 | view_bytecode = (const struct lttng_bytecode *) run_as_ret.u.generate_filter_bytecode.bytecode; |
c73f064a JR |
2019 | |
2020 | local_bytecode = zmalloc(sizeof(*local_bytecode) + view_bytecode->len); | |
2021 | if (!local_bytecode) { | |
2022 | ret = -ENOMEM; | |
2023 | goto error; | |
2024 | } | |
2025 | ||
2026 | memcpy(local_bytecode, run_as_ret.u.generate_filter_bytecode.bytecode, | |
2027 | sizeof(*local_bytecode) + view_bytecode->len); | |
2028 | *bytecode = local_bytecode; | |
2029 | error: | |
2030 | return ret; | |
2031 | } | |
2032 | ||
7567352f | 2033 | LTTNG_HIDDEN |
929f71ec JG |
2034 | int run_as_create_worker(const char *procname, |
2035 | post_fork_cleanup_cb clean_up_func, | |
2036 | void *clean_up_user_data) | |
7567352f | 2037 | { |
8fec83ea | 2038 | int ret; |
7567352f | 2039 | |
749b7a0c | 2040 | pthread_mutex_lock(&worker_lock); |
929f71ec JG |
2041 | ret = run_as_create_worker_no_lock(procname, clean_up_func, |
2042 | clean_up_user_data); | |
749b7a0c | 2043 | pthread_mutex_unlock(&worker_lock); |
7567352f MD |
2044 | return ret; |
2045 | } | |
2046 | ||
2047 | LTTNG_HIDDEN | |
2048 | void run_as_destroy_worker(void) | |
2049 | { | |
749b7a0c | 2050 | pthread_mutex_lock(&worker_lock); |
a01c682b | 2051 | run_as_destroy_worker_no_lock(); |
749b7a0c | 2052 | pthread_mutex_unlock(&worker_lock); |
4628484a | 2053 | } |