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a7e3212d LP |
1 | /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ |
2 | ||
3 | /*** | |
4 | This file is part of systemd. | |
5 | ||
6 | Copyright 2013 Lennart Poettering | |
7 | ||
8 | systemd is free software; you can redistribute it and/or modify it | |
9 | under the terms of the GNU Lesser General Public License as published by | |
10 | the Free Software Foundation; either version 2.1 of the License, or | |
11 | (at your option) any later version. | |
12 | ||
13 | systemd is distributed in the hope that it will be useful, but | |
14 | WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
16 | Lesser General Public License for more details. | |
17 | ||
18 | You should have received a copy of the GNU Lesser General Public License | |
19 | along with systemd; If not, see <http://www.gnu.org/licenses/>. | |
20 | ***/ | |
21 | ||
22 | #include <endian.h> | |
a7e3212d LP |
23 | #include <stdlib.h> |
24 | #include <unistd.h> | |
0a6f50c0 | 25 | #include <poll.h> |
a7e3212d | 26 | |
24882e06 | 27 | #include "sd-daemon.h" |
a7e3212d LP |
28 | #include "util.h" |
29 | #include "macro.h" | |
30 | #include "missing.h" | |
2181a7f5 | 31 | #include "utf8.h" |
6482f626 | 32 | #include "formats-util.h" |
24882e06 | 33 | #include "signal-util.h" |
a7e3212d LP |
34 | |
35 | #include "sd-bus.h" | |
36 | #include "bus-socket.h" | |
37 | #include "bus-internal.h" | |
38 | #include "bus-message.h" | |
39 | ||
aec6d91f LP |
40 | #define SNDBUF_SIZE (8*1024*1024) |
41 | ||
2181a7f5 | 42 | static void iovec_advance(struct iovec iov[], unsigned *idx, size_t size) { |
a7e3212d LP |
43 | |
44 | while (size > 0) { | |
45 | struct iovec *i = iov + *idx; | |
46 | ||
47 | if (i->iov_len > size) { | |
48 | i->iov_base = (uint8_t*) i->iov_base + size; | |
49 | i->iov_len -= size; | |
50 | return; | |
51 | } | |
52 | ||
53 | size -= i->iov_len; | |
54 | ||
55 | i->iov_base = NULL; | |
56 | i->iov_len = 0; | |
57 | ||
58 | (*idx) ++; | |
59 | } | |
60 | } | |
61 | ||
bc7fd8cd | 62 | static int append_iovec(sd_bus_message *m, const void *p, size_t sz) { |
2100fa10 LP |
63 | assert(m); |
64 | assert(p); | |
65 | assert(sz > 0); | |
66 | ||
67 | m->iovec[m->n_iovec].iov_base = (void*) p; | |
68 | m->iovec[m->n_iovec].iov_len = sz; | |
69 | m->n_iovec++; | |
bc7fd8cd LP |
70 | |
71 | return 0; | |
2100fa10 LP |
72 | } |
73 | ||
bc7fd8cd LP |
74 | static int bus_message_setup_iovec(sd_bus_message *m) { |
75 | struct bus_body_part *part; | |
13c299d3 | 76 | unsigned n, i; |
bc7fd8cd LP |
77 | int r; |
78 | ||
2100fa10 LP |
79 | assert(m); |
80 | assert(m->sealed); | |
81 | ||
82 | if (m->n_iovec > 0) | |
bc7fd8cd LP |
83 | return 0; |
84 | ||
85 | assert(!m->iovec); | |
2100fa10 | 86 | |
c91cb83c | 87 | n = 1 + m->n_body_parts; |
bc7fd8cd LP |
88 | if (n < ELEMENTSOF(m->iovec_fixed)) |
89 | m->iovec = m->iovec_fixed; | |
90 | else { | |
91 | m->iovec = new(struct iovec, n); | |
66b26c5c LP |
92 | if (!m->iovec) { |
93 | r = -ENOMEM; | |
94 | goto fail; | |
95 | } | |
bc7fd8cd | 96 | } |
2100fa10 | 97 | |
c91cb83c | 98 | r = append_iovec(m, m->header, BUS_MESSAGE_BODY_BEGIN(m)); |
bc7fd8cd | 99 | if (r < 0) |
66b26c5c | 100 | goto fail; |
2100fa10 | 101 | |
9b29bb68 | 102 | MESSAGE_FOREACH_PART(part, i, m) { |
66b26c5c LP |
103 | r = bus_body_part_map(part); |
104 | if (r < 0) | |
105 | goto fail; | |
106 | ||
bc7fd8cd LP |
107 | r = append_iovec(m, part->data, part->size); |
108 | if (r < 0) | |
66b26c5c | 109 | goto fail; |
bc7fd8cd LP |
110 | } |
111 | ||
112 | assert(n == m->n_iovec); | |
113 | ||
114 | return 0; | |
66b26c5c LP |
115 | |
116 | fail: | |
117 | m->poisoned = true; | |
118 | return r; | |
2100fa10 LP |
119 | } |
120 | ||
2181a7f5 LP |
121 | bool bus_socket_auth_needs_write(sd_bus *b) { |
122 | ||
123 | unsigned i; | |
124 | ||
125 | if (b->auth_index >= ELEMENTSOF(b->auth_iovec)) | |
126 | return false; | |
127 | ||
128 | for (i = b->auth_index; i < ELEMENTSOF(b->auth_iovec); i++) { | |
129 | struct iovec *j = b->auth_iovec + i; | |
130 | ||
131 | if (j->iov_len > 0) | |
132 | return true; | |
133 | } | |
134 | ||
135 | return false; | |
136 | } | |
137 | ||
a7e3212d | 138 | static int bus_socket_write_auth(sd_bus *b) { |
a7e3212d LP |
139 | ssize_t k; |
140 | ||
141 | assert(b); | |
142 | assert(b->state == BUS_AUTHENTICATING); | |
143 | ||
2181a7f5 | 144 | if (!bus_socket_auth_needs_write(b)) |
a7e3212d LP |
145 | return 0; |
146 | ||
15d5af81 LP |
147 | if (b->prefer_writev) |
148 | k = writev(b->output_fd, b->auth_iovec + b->auth_index, ELEMENTSOF(b->auth_iovec) - b->auth_index); | |
149 | else { | |
150 | struct msghdr mh; | |
151 | zero(mh); | |
152 | ||
153 | mh.msg_iov = b->auth_iovec + b->auth_index; | |
154 | mh.msg_iovlen = ELEMENTSOF(b->auth_iovec) - b->auth_index; | |
155 | ||
156 | k = sendmsg(b->output_fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL); | |
157 | if (k < 0 && errno == ENOTSOCK) { | |
158 | b->prefer_writev = true; | |
159 | k = writev(b->output_fd, b->auth_iovec + b->auth_index, ELEMENTSOF(b->auth_iovec) - b->auth_index); | |
160 | } | |
161 | } | |
a7e3212d | 162 | |
a7e3212d LP |
163 | if (k < 0) |
164 | return errno == EAGAIN ? 0 : -errno; | |
165 | ||
166 | iovec_advance(b->auth_iovec, &b->auth_index, (size_t) k); | |
a7e3212d LP |
167 | return 1; |
168 | } | |
169 | ||
2181a7f5 | 170 | static int bus_socket_auth_verify_client(sd_bus *b) { |
a7e3212d LP |
171 | char *e, *f, *start; |
172 | sd_id128_t peer; | |
173 | unsigned i; | |
174 | int r; | |
175 | ||
2181a7f5 LP |
176 | assert(b); |
177 | ||
a7e3212d LP |
178 | /* We expect two response lines: "OK" and possibly |
179 | * "AGREE_UNIX_FD" */ | |
180 | ||
6e6c21c8 | 181 | e = memmem_safe(b->rbuffer, b->rbuffer_size, "\r\n", 2); |
a7e3212d LP |
182 | if (!e) |
183 | return 0; | |
184 | ||
264ad849 | 185 | if (b->hello_flags & KDBUS_HELLO_ACCEPT_FD) { |
a7e3212d LP |
186 | f = memmem(e + 2, b->rbuffer_size - (e - (char*) b->rbuffer) - 2, "\r\n", 2); |
187 | if (!f) | |
188 | return 0; | |
189 | ||
190 | start = f + 2; | |
191 | } else { | |
192 | f = NULL; | |
193 | start = e + 2; | |
194 | } | |
195 | ||
196 | /* Nice! We got all the lines we need. First check the OK | |
197 | * line */ | |
198 | ||
199 | if (e - (char*) b->rbuffer != 3 + 32) | |
200 | return -EPERM; | |
201 | ||
202 | if (memcmp(b->rbuffer, "OK ", 3)) | |
203 | return -EPERM; | |
204 | ||
2181a7f5 LP |
205 | b->auth = b->anonymous_auth ? BUS_AUTH_ANONYMOUS : BUS_AUTH_EXTERNAL; |
206 | ||
a7e3212d LP |
207 | for (i = 0; i < 32; i += 2) { |
208 | int x, y; | |
209 | ||
210 | x = unhexchar(((char*) b->rbuffer)[3 + i]); | |
211 | y = unhexchar(((char*) b->rbuffer)[3 + i + 1]); | |
212 | ||
213 | if (x < 0 || y < 0) | |
214 | return -EINVAL; | |
215 | ||
216 | peer.bytes[i/2] = ((uint8_t) x << 4 | (uint8_t) y); | |
217 | } | |
218 | ||
98178d39 LP |
219 | if (!sd_id128_equal(b->server_id, SD_ID128_NULL) && |
220 | !sd_id128_equal(b->server_id, peer)) | |
a7e3212d LP |
221 | return -EPERM; |
222 | ||
98178d39 | 223 | b->server_id = peer; |
a7e3212d LP |
224 | |
225 | /* And possibly check the second line, too */ | |
226 | ||
227 | if (f) | |
228 | b->can_fds = | |
f8294e41 JT |
229 | (f - e == strlen("\r\nAGREE_UNIX_FD")) && |
230 | memcmp(e + 2, "AGREE_UNIX_FD", strlen("AGREE_UNIX_FD")) == 0; | |
a7e3212d LP |
231 | |
232 | b->rbuffer_size -= (start - (char*) b->rbuffer); | |
233 | memmove(b->rbuffer, start, b->rbuffer_size); | |
234 | ||
235 | r = bus_start_running(b); | |
236 | if (r < 0) | |
237 | return r; | |
238 | ||
239 | return 1; | |
240 | } | |
241 | ||
2181a7f5 LP |
242 | static bool line_equals(const char *s, size_t m, const char *line) { |
243 | size_t l; | |
244 | ||
245 | l = strlen(line); | |
246 | if (l != m) | |
247 | return false; | |
248 | ||
249 | return memcmp(s, line, l) == 0; | |
250 | } | |
251 | ||
252 | static bool line_begins(const char *s, size_t m, const char *word) { | |
253 | size_t l; | |
254 | ||
255 | l = strlen(word); | |
256 | if (m < l) | |
257 | return false; | |
258 | ||
259 | if (memcmp(s, word, l) != 0) | |
260 | return false; | |
261 | ||
262 | return m == l || (m > l && s[l] == ' '); | |
263 | } | |
264 | ||
265 | static int verify_anonymous_token(sd_bus *b, const char *p, size_t l) { | |
266 | _cleanup_free_ char *token = NULL; | |
30494563 TG |
267 | size_t len; |
268 | int r; | |
2181a7f5 LP |
269 | |
270 | if (!b->anonymous_auth) | |
271 | return 0; | |
272 | ||
273 | if (l <= 0) | |
274 | return 1; | |
275 | ||
276 | assert(p[0] == ' '); | |
277 | p++; l--; | |
278 | ||
279 | if (l % 2 != 0) | |
280 | return 0; | |
2181a7f5 | 281 | |
30494563 TG |
282 | r = unhexmem(p, l, (void **) &token, &len); |
283 | if (r < 0) | |
284 | return 0; | |
285 | ||
286 | if (memchr(token, 0, len)) | |
2181a7f5 LP |
287 | return 0; |
288 | ||
289 | return !!utf8_is_valid(token); | |
290 | } | |
291 | ||
292 | static int verify_external_token(sd_bus *b, const char *p, size_t l) { | |
293 | _cleanup_free_ char *token = NULL; | |
30494563 | 294 | size_t len; |
2181a7f5 LP |
295 | uid_t u; |
296 | int r; | |
297 | ||
298 | /* We don't do any real authentication here. Instead, we if | |
299 | * the owner of this bus wanted authentication he should have | |
300 | * checked SO_PEERCRED before even creating the bus object. */ | |
301 | ||
8411d2a2 | 302 | if (!b->anonymous_auth && !b->ucred_valid) |
2181a7f5 LP |
303 | return 0; |
304 | ||
305 | if (l <= 0) | |
306 | return 1; | |
307 | ||
308 | assert(p[0] == ' '); | |
309 | p++; l--; | |
310 | ||
311 | if (l % 2 != 0) | |
312 | return 0; | |
313 | ||
30494563 TG |
314 | r = unhexmem(p, l, (void**) &token, &len); |
315 | if (r < 0) | |
316 | return 0; | |
2181a7f5 | 317 | |
30494563 | 318 | if (memchr(token, 0, len)) |
2181a7f5 LP |
319 | return 0; |
320 | ||
321 | r = parse_uid(token, &u); | |
322 | if (r < 0) | |
323 | return 0; | |
324 | ||
8411d2a2 LP |
325 | /* We ignore the passed value if anonymous authentication is |
326 | * on anyway. */ | |
327 | if (!b->anonymous_auth && u != b->ucred.uid) | |
2181a7f5 LP |
328 | return 0; |
329 | ||
330 | return 1; | |
331 | } | |
332 | ||
333 | static int bus_socket_auth_write(sd_bus *b, const char *t) { | |
334 | char *p; | |
335 | size_t l; | |
336 | ||
337 | assert(b); | |
338 | assert(t); | |
339 | ||
340 | /* We only make use of the first iovec */ | |
341 | assert(b->auth_index == 0 || b->auth_index == 1); | |
342 | ||
343 | l = strlen(t); | |
344 | p = malloc(b->auth_iovec[0].iov_len + l); | |
345 | if (!p) | |
346 | return -ENOMEM; | |
347 | ||
348 | memcpy(p, b->auth_iovec[0].iov_base, b->auth_iovec[0].iov_len); | |
349 | memcpy(p + b->auth_iovec[0].iov_len, t, l); | |
350 | ||
351 | b->auth_iovec[0].iov_base = p; | |
352 | b->auth_iovec[0].iov_len += l; | |
353 | ||
354 | free(b->auth_buffer); | |
355 | b->auth_buffer = p; | |
356 | b->auth_index = 0; | |
357 | return 0; | |
358 | } | |
359 | ||
360 | static int bus_socket_auth_write_ok(sd_bus *b) { | |
361 | char t[3 + 32 + 2 + 1]; | |
362 | ||
363 | assert(b); | |
364 | ||
5ffa8c81 | 365 | xsprintf(t, "OK " SD_ID128_FORMAT_STR "\r\n", SD_ID128_FORMAT_VAL(b->server_id)); |
2181a7f5 LP |
366 | |
367 | return bus_socket_auth_write(b, t); | |
368 | } | |
369 | ||
370 | static int bus_socket_auth_verify_server(sd_bus *b) { | |
371 | char *e; | |
372 | const char *line; | |
373 | size_t l; | |
374 | bool processed = false; | |
375 | int r; | |
376 | ||
377 | assert(b); | |
378 | ||
2b4ac889 | 379 | if (b->rbuffer_size < 1) |
2181a7f5 LP |
380 | return 0; |
381 | ||
382 | /* First char must be a NUL byte */ | |
383 | if (*(char*) b->rbuffer != 0) | |
384 | return -EIO; | |
385 | ||
2b4ac889 LP |
386 | if (b->rbuffer_size < 3) |
387 | return 0; | |
388 | ||
2181a7f5 LP |
389 | /* Begin with the first line */ |
390 | if (b->auth_rbegin <= 0) | |
391 | b->auth_rbegin = 1; | |
392 | ||
393 | for (;;) { | |
394 | /* Check if line is complete */ | |
395 | line = (char*) b->rbuffer + b->auth_rbegin; | |
396 | e = memmem(line, b->rbuffer_size - b->auth_rbegin, "\r\n", 2); | |
397 | if (!e) | |
398 | return processed; | |
399 | ||
400 | l = e - line; | |
401 | ||
402 | if (line_begins(line, l, "AUTH ANONYMOUS")) { | |
403 | ||
404 | r = verify_anonymous_token(b, line + 14, l - 14); | |
405 | if (r < 0) | |
406 | return r; | |
407 | if (r == 0) | |
408 | r = bus_socket_auth_write(b, "REJECTED\r\n"); | |
409 | else { | |
410 | b->auth = BUS_AUTH_ANONYMOUS; | |
411 | r = bus_socket_auth_write_ok(b); | |
412 | } | |
413 | ||
414 | } else if (line_begins(line, l, "AUTH EXTERNAL")) { | |
415 | ||
416 | r = verify_external_token(b, line + 13, l - 13); | |
417 | if (r < 0) | |
418 | return r; | |
419 | if (r == 0) | |
420 | r = bus_socket_auth_write(b, "REJECTED\r\n"); | |
421 | else { | |
422 | b->auth = BUS_AUTH_EXTERNAL; | |
423 | r = bus_socket_auth_write_ok(b); | |
424 | } | |
425 | ||
426 | } else if (line_begins(line, l, "AUTH")) | |
427 | r = bus_socket_auth_write(b, "REJECTED EXTERNAL ANONYMOUS\r\n"); | |
428 | else if (line_equals(line, l, "CANCEL") || | |
429 | line_begins(line, l, "ERROR")) { | |
430 | ||
431 | b->auth = _BUS_AUTH_INVALID; | |
432 | r = bus_socket_auth_write(b, "REJECTED\r\n"); | |
433 | ||
434 | } else if (line_equals(line, l, "BEGIN")) { | |
435 | ||
436 | if (b->auth == _BUS_AUTH_INVALID) | |
437 | r = bus_socket_auth_write(b, "ERROR\r\n"); | |
438 | else { | |
439 | /* We can't leave from the auth phase | |
440 | * before we haven't written | |
441 | * everything queued, so let's check | |
442 | * that */ | |
443 | ||
444 | if (bus_socket_auth_needs_write(b)) | |
445 | return 1; | |
446 | ||
447 | b->rbuffer_size -= (e + 2 - (char*) b->rbuffer); | |
448 | memmove(b->rbuffer, e + 2, b->rbuffer_size); | |
449 | return bus_start_running(b); | |
450 | } | |
451 | ||
452 | } else if (line_begins(line, l, "DATA")) { | |
453 | ||
454 | if (b->auth == _BUS_AUTH_INVALID) | |
455 | r = bus_socket_auth_write(b, "ERROR\r\n"); | |
456 | else { | |
457 | if (b->auth == BUS_AUTH_ANONYMOUS) | |
458 | r = verify_anonymous_token(b, line + 4, l - 4); | |
459 | else | |
460 | r = verify_external_token(b, line + 4, l - 4); | |
461 | ||
462 | if (r < 0) | |
463 | return r; | |
464 | if (r == 0) { | |
465 | b->auth = _BUS_AUTH_INVALID; | |
466 | r = bus_socket_auth_write(b, "REJECTED\r\n"); | |
467 | } else | |
468 | r = bus_socket_auth_write_ok(b); | |
469 | } | |
470 | } else if (line_equals(line, l, "NEGOTIATE_UNIX_FD")) { | |
264ad849 | 471 | if (b->auth == _BUS_AUTH_INVALID || !(b->hello_flags & KDBUS_HELLO_ACCEPT_FD)) |
2181a7f5 LP |
472 | r = bus_socket_auth_write(b, "ERROR\r\n"); |
473 | else { | |
474 | b->can_fds = true; | |
475 | r = bus_socket_auth_write(b, "AGREE_UNIX_FD\r\n"); | |
476 | } | |
477 | } else | |
478 | r = bus_socket_auth_write(b, "ERROR\r\n"); | |
479 | ||
480 | if (r < 0) | |
481 | return r; | |
482 | ||
483 | b->auth_rbegin = e + 2 - (char*) b->rbuffer; | |
484 | ||
485 | processed = true; | |
486 | } | |
487 | } | |
488 | ||
489 | static int bus_socket_auth_verify(sd_bus *b) { | |
490 | assert(b); | |
491 | ||
492 | if (b->is_server) | |
493 | return bus_socket_auth_verify_server(b); | |
494 | else | |
495 | return bus_socket_auth_verify_client(b); | |
496 | } | |
497 | ||
a7e3212d LP |
498 | static int bus_socket_read_auth(sd_bus *b) { |
499 | struct msghdr mh; | |
7f4e6a1c | 500 | struct iovec iov = {}; |
a7e3212d LP |
501 | size_t n; |
502 | ssize_t k; | |
503 | int r; | |
504 | void *p; | |
2181a7f5 LP |
505 | union { |
506 | struct cmsghdr cmsghdr; | |
d868f2a3 | 507 | uint8_t buf[CMSG_SPACE(sizeof(int) * BUS_FDS_MAX)]; |
2181a7f5 | 508 | } control; |
15d5af81 | 509 | bool handle_cmsg = false; |
a7e3212d LP |
510 | |
511 | assert(b); | |
2181a7f5 | 512 | assert(b->state == BUS_AUTHENTICATING); |
a7e3212d LP |
513 | |
514 | r = bus_socket_auth_verify(b); | |
515 | if (r != 0) | |
516 | return r; | |
517 | ||
9607d947 | 518 | n = MAX(256u, b->rbuffer_size * 2); |
a7e3212d LP |
519 | |
520 | if (n > BUS_AUTH_SIZE_MAX) | |
521 | n = BUS_AUTH_SIZE_MAX; | |
522 | ||
523 | if (b->rbuffer_size >= n) | |
524 | return -ENOBUFS; | |
525 | ||
526 | p = realloc(b->rbuffer, n); | |
527 | if (!p) | |
528 | return -ENOMEM; | |
529 | ||
530 | b->rbuffer = p; | |
531 | ||
a7e3212d LP |
532 | iov.iov_base = (uint8_t*) b->rbuffer + b->rbuffer_size; |
533 | iov.iov_len = n - b->rbuffer_size; | |
534 | ||
15d5af81 LP |
535 | if (b->prefer_readv) |
536 | k = readv(b->input_fd, &iov, 1); | |
537 | else { | |
538 | zero(mh); | |
539 | mh.msg_iov = &iov; | |
540 | mh.msg_iovlen = 1; | |
541 | mh.msg_control = &control; | |
542 | mh.msg_controllen = sizeof(control); | |
543 | ||
544 | k = recvmsg(b->input_fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC); | |
545 | if (k < 0 && errno == ENOTSOCK) { | |
546 | b->prefer_readv = true; | |
547 | k = readv(b->input_fd, &iov, 1); | |
548 | } else | |
549 | handle_cmsg = true; | |
550 | } | |
a7e3212d LP |
551 | if (k < 0) |
552 | return errno == EAGAIN ? 0 : -errno; | |
553 | if (k == 0) | |
554 | return -ECONNRESET; | |
555 | ||
556 | b->rbuffer_size += k; | |
557 | ||
2a1288ff LP |
558 | if (handle_cmsg) { |
559 | struct cmsghdr *cmsg; | |
560 | ||
561 | CMSG_FOREACH(cmsg, &mh) | |
15d5af81 LP |
562 | if (cmsg->cmsg_level == SOL_SOCKET && |
563 | cmsg->cmsg_type == SCM_RIGHTS) { | |
564 | int j; | |
565 | ||
566 | /* Whut? We received fds during the auth | |
567 | * protocol? Somebody is playing games with | |
568 | * us. Close them all, and fail */ | |
569 | j = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int); | |
570 | close_many((int*) CMSG_DATA(cmsg), j); | |
571 | return -EIO; | |
d868f2a3 ZJS |
572 | } else |
573 | log_debug("Got unexpected auxiliary data with level=%d and type=%d", | |
574 | cmsg->cmsg_level, cmsg->cmsg_type); | |
2a1288ff | 575 | } |
2181a7f5 | 576 | |
a7e3212d LP |
577 | r = bus_socket_auth_verify(b); |
578 | if (r != 0) | |
579 | return r; | |
580 | ||
581 | return 1; | |
582 | } | |
583 | ||
8f04d2eb | 584 | void bus_socket_setup(sd_bus *b) { |
a7e3212d LP |
585 | assert(b); |
586 | ||
aec6d91f LP |
587 | /* Increase the buffers to 8 MB */ |
588 | fd_inc_rcvbuf(b->input_fd, SNDBUF_SIZE); | |
589 | fd_inc_sndbuf(b->output_fd, SNDBUF_SIZE); | |
a7e3212d | 590 | |
e1d337d4 LP |
591 | b->is_kernel = false; |
592 | b->message_version = 1; | |
0f437184 | 593 | b->message_endian = 0; |
8f04d2eb | 594 | } |
e1d337d4 | 595 | |
8f04d2eb | 596 | static void bus_get_peercred(sd_bus *b) { |
c4e6556c ZJS |
597 | int r; |
598 | ||
8f04d2eb LP |
599 | assert(b); |
600 | ||
601 | /* Get the peer for socketpair() sockets */ | |
eff05270 | 602 | b->ucred_valid = getpeercred(b->input_fd, &b->ucred) >= 0; |
c4e6556c ZJS |
603 | |
604 | /* Get the SELinux context of the peer */ | |
605 | r = getpeersec(b->input_fd, &b->label); | |
606 | if (r < 0 && r != -EOPNOTSUPP) | |
607 | log_debug_errno(r, "Failed to determine peer security context: %m"); | |
a7e3212d LP |
608 | } |
609 | ||
2181a7f5 | 610 | static int bus_socket_start_auth_client(sd_bus *b) { |
a7e3212d | 611 | size_t l; |
2181a7f5 | 612 | const char *auth_suffix, *auth_prefix; |
a7e3212d LP |
613 | |
614 | assert(b); | |
615 | ||
2181a7f5 LP |
616 | if (b->anonymous_auth) { |
617 | auth_prefix = "\0AUTH ANONYMOUS "; | |
a7e3212d | 618 | |
2181a7f5 LP |
619 | /* For ANONYMOUS auth we send some arbitrary "trace" string */ |
620 | l = 9; | |
621 | b->auth_buffer = hexmem("anonymous", l); | |
622 | } else { | |
5ffa8c81 | 623 | char text[DECIMAL_STR_MAX(uid_t) + 1]; |
a7e3212d | 624 | |
2181a7f5 | 625 | auth_prefix = "\0AUTH EXTERNAL "; |
a7e3212d | 626 | |
5ffa8c81 | 627 | xsprintf(text, UID_FMT, geteuid()); |
a7e3212d | 628 | |
2181a7f5 LP |
629 | l = strlen(text); |
630 | b->auth_buffer = hexmem(text, l); | |
631 | } | |
632 | ||
633 | if (!b->auth_buffer) | |
a7e3212d LP |
634 | return -ENOMEM; |
635 | ||
264ad849 | 636 | if (b->hello_flags & KDBUS_HELLO_ACCEPT_FD) |
2181a7f5 LP |
637 | auth_suffix = "\r\nNEGOTIATE_UNIX_FD\r\nBEGIN\r\n"; |
638 | else | |
639 | auth_suffix = "\r\nBEGIN\r\n"; | |
a7e3212d LP |
640 | |
641 | b->auth_iovec[0].iov_base = (void*) auth_prefix; | |
2181a7f5 LP |
642 | b->auth_iovec[0].iov_len = 1 + strlen(auth_prefix + 1); |
643 | b->auth_iovec[1].iov_base = (void*) b->auth_buffer; | |
a7e3212d LP |
644 | b->auth_iovec[1].iov_len = l * 2; |
645 | b->auth_iovec[2].iov_base = (void*) auth_suffix; | |
646 | b->auth_iovec[2].iov_len = strlen(auth_suffix); | |
a7e3212d LP |
647 | |
648 | return bus_socket_write_auth(b); | |
649 | } | |
650 | ||
a7893c6b | 651 | int bus_socket_start_auth(sd_bus *b) { |
2181a7f5 LP |
652 | assert(b); |
653 | ||
8f04d2eb LP |
654 | bus_get_peercred(b); |
655 | ||
2181a7f5 LP |
656 | b->state = BUS_AUTHENTICATING; |
657 | b->auth_timeout = now(CLOCK_MONOTONIC) + BUS_DEFAULT_TIMEOUT; | |
658 | ||
9ab32f9d | 659 | if (sd_is_socket(b->input_fd, AF_UNIX, 0, 0) <= 0) |
264ad849 | 660 | b->hello_flags &= ~KDBUS_HELLO_ACCEPT_FD; |
2181a7f5 | 661 | |
9ab32f9d LP |
662 | if (b->output_fd != b->input_fd) |
663 | if (sd_is_socket(b->output_fd, AF_UNIX, 0, 0) <= 0) | |
264ad849 | 664 | b->hello_flags &= ~KDBUS_HELLO_ACCEPT_FD; |
e82c9509 | 665 | |
2181a7f5 LP |
666 | if (b->is_server) |
667 | return bus_socket_read_auth(b); | |
668 | else | |
669 | return bus_socket_start_auth_client(b); | |
670 | } | |
671 | ||
a7e3212d LP |
672 | int bus_socket_connect(sd_bus *b) { |
673 | int r; | |
674 | ||
675 | assert(b); | |
e82c9509 LP |
676 | assert(b->input_fd < 0); |
677 | assert(b->output_fd < 0); | |
a7e3212d LP |
678 | assert(b->sockaddr.sa.sa_family != AF_UNSPEC); |
679 | ||
e82c9509 LP |
680 | b->input_fd = socket(b->sockaddr.sa.sa_family, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0); |
681 | if (b->input_fd < 0) | |
a7e3212d LP |
682 | return -errno; |
683 | ||
e82c9509 LP |
684 | b->output_fd = b->input_fd; |
685 | ||
8f04d2eb | 686 | bus_socket_setup(b); |
a7e3212d | 687 | |
e82c9509 | 688 | r = connect(b->input_fd, &b->sockaddr.sa, b->sockaddr_size); |
a7e3212d LP |
689 | if (r < 0) { |
690 | if (errno == EINPROGRESS) | |
691 | return 1; | |
692 | ||
693 | return -errno; | |
694 | } | |
695 | ||
696 | return bus_socket_start_auth(b); | |
697 | } | |
698 | ||
699 | int bus_socket_exec(sd_bus *b) { | |
e82c9509 | 700 | int s[2], r; |
a7e3212d LP |
701 | pid_t pid; |
702 | ||
703 | assert(b); | |
e82c9509 LP |
704 | assert(b->input_fd < 0); |
705 | assert(b->output_fd < 0); | |
a7e3212d LP |
706 | assert(b->exec_path); |
707 | ||
e82c9509 LP |
708 | r = socketpair(AF_UNIX, SOCK_STREAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0, s); |
709 | if (r < 0) | |
a7e3212d LP |
710 | return -errno; |
711 | ||
712 | pid = fork(); | |
713 | if (pid < 0) { | |
3d94f76c | 714 | safe_close_pair(s); |
a7e3212d LP |
715 | return -errno; |
716 | } | |
717 | if (pid == 0) { | |
718 | /* Child */ | |
719 | ||
ce30c8dc LP |
720 | (void) reset_all_signal_handlers(); |
721 | (void) reset_signal_mask(); | |
e82c9509 LP |
722 | |
723 | close_all_fds(s+1, 1); | |
a7e3212d LP |
724 | |
725 | assert_se(dup3(s[1], STDIN_FILENO, 0) == STDIN_FILENO); | |
726 | assert_se(dup3(s[1], STDOUT_FILENO, 0) == STDOUT_FILENO); | |
727 | ||
728 | if (s[1] != STDIN_FILENO && s[1] != STDOUT_FILENO) | |
03e334a1 | 729 | safe_close(s[1]); |
a7e3212d LP |
730 | |
731 | fd_cloexec(STDIN_FILENO, false); | |
732 | fd_cloexec(STDOUT_FILENO, false); | |
733 | fd_nonblock(STDIN_FILENO, false); | |
734 | fd_nonblock(STDOUT_FILENO, false); | |
735 | ||
736 | if (b->exec_argv) | |
737 | execvp(b->exec_path, b->exec_argv); | |
738 | else { | |
739 | const char *argv[] = { b->exec_path, NULL }; | |
740 | execvp(b->exec_path, (char**) argv); | |
741 | } | |
742 | ||
743 | _exit(EXIT_FAILURE); | |
744 | } | |
745 | ||
03e334a1 | 746 | safe_close(s[1]); |
e82c9509 | 747 | b->output_fd = b->input_fd = s[0]; |
a7e3212d | 748 | |
8f04d2eb | 749 | bus_socket_setup(b); |
e1d337d4 | 750 | |
a7e3212d LP |
751 | return bus_socket_start_auth(b); |
752 | } | |
753 | ||
754 | int bus_socket_take_fd(sd_bus *b) { | |
a7e3212d LP |
755 | assert(b); |
756 | ||
8f04d2eb | 757 | bus_socket_setup(b); |
a7e3212d LP |
758 | |
759 | return bus_socket_start_auth(b); | |
760 | } | |
761 | ||
762 | int bus_socket_write_message(sd_bus *bus, sd_bus_message *m, size_t *idx) { | |
a7e3212d LP |
763 | struct iovec *iov; |
764 | ssize_t k; | |
765 | size_t n; | |
766 | unsigned j; | |
bc7fd8cd | 767 | int r; |
a7e3212d LP |
768 | |
769 | assert(bus); | |
770 | assert(m); | |
771 | assert(idx); | |
772 | assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO); | |
773 | ||
6629161f | 774 | if (*idx >= BUS_MESSAGE_SIZE(m)) |
a7e3212d | 775 | return 0; |
a7e3212d | 776 | |
bc7fd8cd LP |
777 | r = bus_message_setup_iovec(m); |
778 | if (r < 0) | |
779 | return r; | |
2100fa10 | 780 | |
a7e3212d LP |
781 | n = m->n_iovec * sizeof(struct iovec); |
782 | iov = alloca(n); | |
783 | memcpy(iov, m->iovec, n); | |
784 | ||
785 | j = 0; | |
786 | iovec_advance(iov, &j, *idx); | |
787 | ||
15d5af81 LP |
788 | if (bus->prefer_writev) |
789 | k = writev(bus->output_fd, iov, m->n_iovec); | |
790 | else { | |
7f4e6a1c ZJS |
791 | struct msghdr mh = { |
792 | .msg_iov = iov, | |
793 | .msg_iovlen = m->n_iovec, | |
794 | }; | |
15d5af81 LP |
795 | |
796 | if (m->n_fds > 0) { | |
797 | struct cmsghdr *control; | |
15d5af81 | 798 | |
7f4e6a1c ZJS |
799 | mh.msg_control = control = alloca(CMSG_SPACE(sizeof(int) * m->n_fds)); |
800 | mh.msg_controllen = control->cmsg_len = CMSG_LEN(sizeof(int) * m->n_fds); | |
15d5af81 LP |
801 | control->cmsg_level = SOL_SOCKET; |
802 | control->cmsg_type = SCM_RIGHTS; | |
15d5af81 LP |
803 | memcpy(CMSG_DATA(control), m->fds, sizeof(int) * m->n_fds); |
804 | } | |
805 | ||
15d5af81 LP |
806 | k = sendmsg(bus->output_fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL); |
807 | if (k < 0 && errno == ENOTSOCK) { | |
808 | bus->prefer_writev = true; | |
809 | k = writev(bus->output_fd, iov, m->n_iovec); | |
810 | } | |
811 | } | |
a7e3212d | 812 | |
a7e3212d LP |
813 | if (k < 0) |
814 | return errno == EAGAIN ? 0 : -errno; | |
815 | ||
816 | *idx += (size_t) k; | |
817 | return 1; | |
818 | } | |
819 | ||
820 | static int bus_socket_read_message_need(sd_bus *bus, size_t *need) { | |
821 | uint32_t a, b; | |
822 | uint8_t e; | |
823 | uint64_t sum; | |
824 | ||
825 | assert(bus); | |
826 | assert(need); | |
827 | assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO); | |
828 | ||
829 | if (bus->rbuffer_size < sizeof(struct bus_header)) { | |
830 | *need = sizeof(struct bus_header) + 8; | |
831 | ||
832 | /* Minimum message size: | |
833 | * | |
834 | * Header + | |
835 | * | |
836 | * Method Call: +2 string headers | |
837 | * Signal: +3 string headers | |
838 | * Method Error: +1 string headers | |
839 | * +1 uint32 headers | |
840 | * Method Reply: +1 uint32 headers | |
841 | * | |
842 | * A string header is at least 9 bytes | |
843 | * A uint32 header is at least 8 bytes | |
844 | * | |
845 | * Hence the minimum message size of a valid message | |
846 | * is header + 8 bytes */ | |
847 | ||
848 | return 0; | |
849 | } | |
850 | ||
851 | a = ((const uint32_t*) bus->rbuffer)[1]; | |
852 | b = ((const uint32_t*) bus->rbuffer)[3]; | |
853 | ||
854 | e = ((const uint8_t*) bus->rbuffer)[0]; | |
0461f8cd | 855 | if (e == BUS_LITTLE_ENDIAN) { |
a7e3212d LP |
856 | a = le32toh(a); |
857 | b = le32toh(b); | |
0461f8cd | 858 | } else if (e == BUS_BIG_ENDIAN) { |
a7e3212d LP |
859 | a = be32toh(a); |
860 | b = be32toh(b); | |
861 | } else | |
862 | return -EBADMSG; | |
863 | ||
864 | sum = (uint64_t) sizeof(struct bus_header) + (uint64_t) ALIGN_TO(b, 8) + (uint64_t) a; | |
865 | if (sum >= BUS_MESSAGE_SIZE_MAX) | |
866 | return -ENOBUFS; | |
867 | ||
868 | *need = (size_t) sum; | |
869 | return 0; | |
870 | } | |
871 | ||
7d22c717 | 872 | static int bus_socket_make_message(sd_bus *bus, size_t size) { |
a7e3212d LP |
873 | sd_bus_message *t; |
874 | void *b; | |
875 | int r; | |
876 | ||
877 | assert(bus); | |
a7e3212d LP |
878 | assert(bus->rbuffer_size >= size); |
879 | assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO); | |
880 | ||
7adc46fc LP |
881 | r = bus_rqueue_make_room(bus); |
882 | if (r < 0) | |
883 | return r; | |
884 | ||
a7e3212d LP |
885 | if (bus->rbuffer_size > size) { |
886 | b = memdup((const uint8_t*) bus->rbuffer + size, | |
887 | bus->rbuffer_size - size); | |
888 | if (!b) | |
889 | return -ENOMEM; | |
890 | } else | |
891 | b = NULL; | |
892 | ||
df2d202e LP |
893 | r = bus_message_from_malloc(bus, |
894 | bus->rbuffer, size, | |
a7e3212d | 895 | bus->fds, bus->n_fds, |
038f9863 | 896 | NULL, |
a7e3212d LP |
897 | &t); |
898 | if (r < 0) { | |
899 | free(b); | |
900 | return r; | |
901 | } | |
902 | ||
903 | bus->rbuffer = b; | |
904 | bus->rbuffer_size -= size; | |
905 | ||
906 | bus->fds = NULL; | |
907 | bus->n_fds = 0; | |
908 | ||
7adc46fc | 909 | bus->rqueue[bus->rqueue_size++] = t; |
7d22c717 | 910 | |
a7e3212d LP |
911 | return 1; |
912 | } | |
913 | ||
7d22c717 | 914 | int bus_socket_read_message(sd_bus *bus) { |
a7e3212d | 915 | struct msghdr mh; |
7f4e6a1c | 916 | struct iovec iov = {}; |
a7e3212d LP |
917 | ssize_t k; |
918 | size_t need; | |
919 | int r; | |
920 | void *b; | |
921 | union { | |
922 | struct cmsghdr cmsghdr; | |
d868f2a3 | 923 | uint8_t buf[CMSG_SPACE(sizeof(int) * BUS_FDS_MAX)]; |
a7e3212d | 924 | } control; |
4d3a5b10 | 925 | bool handle_cmsg = false; |
a7e3212d LP |
926 | |
927 | assert(bus); | |
a7e3212d LP |
928 | assert(bus->state == BUS_RUNNING || bus->state == BUS_HELLO); |
929 | ||
930 | r = bus_socket_read_message_need(bus, &need); | |
931 | if (r < 0) | |
932 | return r; | |
933 | ||
934 | if (bus->rbuffer_size >= need) | |
7d22c717 | 935 | return bus_socket_make_message(bus, need); |
a7e3212d LP |
936 | |
937 | b = realloc(bus->rbuffer, need); | |
938 | if (!b) | |
939 | return -ENOMEM; | |
940 | ||
941 | bus->rbuffer = b; | |
942 | ||
a7e3212d LP |
943 | iov.iov_base = (uint8_t*) bus->rbuffer + bus->rbuffer_size; |
944 | iov.iov_len = need - bus->rbuffer_size; | |
945 | ||
15d5af81 LP |
946 | if (bus->prefer_readv) |
947 | k = readv(bus->input_fd, &iov, 1); | |
948 | else { | |
949 | zero(mh); | |
950 | mh.msg_iov = &iov; | |
951 | mh.msg_iovlen = 1; | |
952 | mh.msg_control = &control; | |
953 | mh.msg_controllen = sizeof(control); | |
954 | ||
955 | k = recvmsg(bus->input_fd, &mh, MSG_DONTWAIT|MSG_NOSIGNAL|MSG_CMSG_CLOEXEC); | |
956 | if (k < 0 && errno == ENOTSOCK) { | |
957 | bus->prefer_readv = true; | |
958 | k = readv(bus->input_fd, &iov, 1); | |
959 | } else | |
960 | handle_cmsg = true; | |
961 | } | |
a7e3212d LP |
962 | if (k < 0) |
963 | return errno == EAGAIN ? 0 : -errno; | |
964 | if (k == 0) | |
965 | return -ECONNRESET; | |
966 | ||
967 | bus->rbuffer_size += k; | |
968 | ||
2a1288ff LP |
969 | if (handle_cmsg) { |
970 | struct cmsghdr *cmsg; | |
971 | ||
972 | CMSG_FOREACH(cmsg, &mh) | |
15d5af81 LP |
973 | if (cmsg->cmsg_level == SOL_SOCKET && |
974 | cmsg->cmsg_type == SCM_RIGHTS) { | |
975 | int n, *f; | |
976 | ||
977 | n = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int); | |
978 | ||
979 | if (!bus->can_fds) { | |
980 | /* Whut? We received fds but this | |
981 | * isn't actually enabled? Close them, | |
982 | * and fail */ | |
983 | ||
984 | close_many((int*) CMSG_DATA(cmsg), n); | |
985 | return -EIO; | |
986 | } | |
987 | ||
988 | f = realloc(bus->fds, sizeof(int) + (bus->n_fds + n)); | |
989 | if (!f) { | |
990 | close_many((int*) CMSG_DATA(cmsg), n); | |
991 | return -ENOMEM; | |
992 | } | |
993 | ||
994 | memcpy(f + bus->n_fds, CMSG_DATA(cmsg), n * sizeof(int)); | |
995 | bus->fds = f; | |
996 | bus->n_fds += n; | |
d868f2a3 ZJS |
997 | } else |
998 | log_debug("Got unexpected auxiliary data with level=%d and type=%d", | |
999 | cmsg->cmsg_level, cmsg->cmsg_type); | |
2a1288ff | 1000 | } |
a7e3212d LP |
1001 | |
1002 | r = bus_socket_read_message_need(bus, &need); | |
1003 | if (r < 0) | |
1004 | return r; | |
1005 | ||
1006 | if (bus->rbuffer_size >= need) | |
7d22c717 | 1007 | return bus_socket_make_message(bus, need); |
a7e3212d LP |
1008 | |
1009 | return 1; | |
1010 | } | |
1011 | ||
1012 | int bus_socket_process_opening(sd_bus *b) { | |
1013 | int error = 0; | |
1014 | socklen_t slen = sizeof(error); | |
b92bea5d ZJS |
1015 | struct pollfd p = { |
1016 | .fd = b->output_fd, | |
1017 | .events = POLLOUT, | |
1018 | }; | |
a7e3212d LP |
1019 | int r; |
1020 | ||
a7e3212d LP |
1021 | assert(b->state == BUS_OPENING); |
1022 | ||
a7e3212d LP |
1023 | r = poll(&p, 1, 0); |
1024 | if (r < 0) | |
1025 | return -errno; | |
1026 | ||
1027 | if (!(p.revents & (POLLOUT|POLLERR|POLLHUP))) | |
1028 | return 0; | |
1029 | ||
e82c9509 | 1030 | r = getsockopt(b->output_fd, SOL_SOCKET, SO_ERROR, &error, &slen); |
a7e3212d LP |
1031 | if (r < 0) |
1032 | b->last_connect_error = errno; | |
1033 | else if (error != 0) | |
1034 | b->last_connect_error = error; | |
1035 | else if (p.revents & (POLLERR|POLLHUP)) | |
1036 | b->last_connect_error = ECONNREFUSED; | |
1037 | else | |
1038 | return bus_socket_start_auth(b); | |
1039 | ||
1040 | return bus_next_address(b); | |
1041 | } | |
1042 | ||
1043 | int bus_socket_process_authenticating(sd_bus *b) { | |
1044 | int r; | |
1045 | ||
1046 | assert(b); | |
1047 | assert(b->state == BUS_AUTHENTICATING); | |
1048 | ||
1049 | if (now(CLOCK_MONOTONIC) >= b->auth_timeout) | |
1050 | return -ETIMEDOUT; | |
1051 | ||
1052 | r = bus_socket_write_auth(b); | |
1053 | if (r != 0) | |
1054 | return r; | |
1055 | ||
1056 | return bus_socket_read_auth(b); | |
1057 | } |