]>
Commit | Line | Data |
---|---|---|
1 | /* | |
2 | * Copyright (C) 2016-2018 Red Hat, Inc. | |
3 | * Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws> | |
4 | * | |
5 | * Network Block Device Server Side | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License as published by | |
9 | * the Free Software Foundation; under version 2 of the License. | |
10 | * | |
11 | * This program is distributed in the hope that it will be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | * GNU General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * along with this program; if not, see <http://www.gnu.org/licenses/>. | |
18 | */ | |
19 | ||
20 | #include "qemu/osdep.h" | |
21 | #include "qapi/error.h" | |
22 | #include "qemu/queue.h" | |
23 | #include "trace.h" | |
24 | #include "nbd-internal.h" | |
25 | #include "qemu/units.h" | |
26 | ||
27 | #define NBD_META_ID_BASE_ALLOCATION 0 | |
28 | #define NBD_META_ID_DIRTY_BITMAP 1 | |
29 | ||
30 | /* | |
31 | * NBD_MAX_BLOCK_STATUS_EXTENTS: 1 MiB of extents data. An empirical | |
32 | * constant. If an increase is needed, note that the NBD protocol | |
33 | * recommends no larger than 32 mb, so that the client won't consider | |
34 | * the reply as a denial of service attack. | |
35 | */ | |
36 | #define NBD_MAX_BLOCK_STATUS_EXTENTS (1 * MiB / 8) | |
37 | ||
38 | static int system_errno_to_nbd_errno(int err) | |
39 | { | |
40 | switch (err) { | |
41 | case 0: | |
42 | return NBD_SUCCESS; | |
43 | case EPERM: | |
44 | case EROFS: | |
45 | return NBD_EPERM; | |
46 | case EIO: | |
47 | return NBD_EIO; | |
48 | case ENOMEM: | |
49 | return NBD_ENOMEM; | |
50 | #ifdef EDQUOT | |
51 | case EDQUOT: | |
52 | #endif | |
53 | case EFBIG: | |
54 | case ENOSPC: | |
55 | return NBD_ENOSPC; | |
56 | case EOVERFLOW: | |
57 | return NBD_EOVERFLOW; | |
58 | case ENOTSUP: | |
59 | #if ENOTSUP != EOPNOTSUPP | |
60 | case EOPNOTSUPP: | |
61 | #endif | |
62 | return NBD_ENOTSUP; | |
63 | case ESHUTDOWN: | |
64 | return NBD_ESHUTDOWN; | |
65 | case EINVAL: | |
66 | default: | |
67 | return NBD_EINVAL; | |
68 | } | |
69 | } | |
70 | ||
71 | /* Definitions for opaque data types */ | |
72 | ||
73 | typedef struct NBDRequestData NBDRequestData; | |
74 | ||
75 | struct NBDRequestData { | |
76 | QSIMPLEQ_ENTRY(NBDRequestData) entry; | |
77 | NBDClient *client; | |
78 | uint8_t *data; | |
79 | bool complete; | |
80 | }; | |
81 | ||
82 | struct NBDExport { | |
83 | int refcount; | |
84 | void (*close)(NBDExport *exp); | |
85 | ||
86 | BlockBackend *blk; | |
87 | char *name; | |
88 | char *description; | |
89 | uint64_t dev_offset; | |
90 | uint64_t size; | |
91 | uint16_t nbdflags; | |
92 | QTAILQ_HEAD(, NBDClient) clients; | |
93 | QTAILQ_ENTRY(NBDExport) next; | |
94 | ||
95 | AioContext *ctx; | |
96 | ||
97 | BlockBackend *eject_notifier_blk; | |
98 | Notifier eject_notifier; | |
99 | ||
100 | BdrvDirtyBitmap *export_bitmap; | |
101 | char *export_bitmap_context; | |
102 | }; | |
103 | ||
104 | static QTAILQ_HEAD(, NBDExport) exports = QTAILQ_HEAD_INITIALIZER(exports); | |
105 | static QTAILQ_HEAD(, NBDExport) closed_exports = | |
106 | QTAILQ_HEAD_INITIALIZER(closed_exports); | |
107 | ||
108 | /* NBDExportMetaContexts represents a list of contexts to be exported, | |
109 | * as selected by NBD_OPT_SET_META_CONTEXT. Also used for | |
110 | * NBD_OPT_LIST_META_CONTEXT. */ | |
111 | typedef struct NBDExportMetaContexts { | |
112 | NBDExport *exp; | |
113 | bool valid; /* means that negotiation of the option finished without | |
114 | errors */ | |
115 | bool base_allocation; /* export base:allocation context (block status) */ | |
116 | bool bitmap; /* export qemu:dirty-bitmap:<export bitmap name> */ | |
117 | } NBDExportMetaContexts; | |
118 | ||
119 | struct NBDClient { | |
120 | int refcount; | |
121 | void (*close_fn)(NBDClient *client, bool negotiated); | |
122 | ||
123 | NBDExport *exp; | |
124 | QCryptoTLSCreds *tlscreds; | |
125 | char *tlsauthz; | |
126 | QIOChannelSocket *sioc; /* The underlying data channel */ | |
127 | QIOChannel *ioc; /* The current I/O channel which may differ (eg TLS) */ | |
128 | ||
129 | Coroutine *recv_coroutine; | |
130 | ||
131 | CoMutex send_lock; | |
132 | Coroutine *send_coroutine; | |
133 | ||
134 | QTAILQ_ENTRY(NBDClient) next; | |
135 | int nb_requests; | |
136 | bool closing; | |
137 | ||
138 | uint32_t check_align; /* If non-zero, check for aligned client requests */ | |
139 | ||
140 | bool structured_reply; | |
141 | NBDExportMetaContexts export_meta; | |
142 | ||
143 | uint32_t opt; /* Current option being negotiated */ | |
144 | uint32_t optlen; /* remaining length of data in ioc for the option being | |
145 | negotiated now */ | |
146 | }; | |
147 | ||
148 | static void nbd_client_receive_next_request(NBDClient *client); | |
149 | ||
150 | /* Basic flow for negotiation | |
151 | ||
152 | Server Client | |
153 | Negotiate | |
154 | ||
155 | or | |
156 | ||
157 | Server Client | |
158 | Negotiate #1 | |
159 | Option | |
160 | Negotiate #2 | |
161 | ||
162 | ---- | |
163 | ||
164 | followed by | |
165 | ||
166 | Server Client | |
167 | Request | |
168 | Response | |
169 | Request | |
170 | Response | |
171 | ... | |
172 | ... | |
173 | Request (type == 2) | |
174 | ||
175 | */ | |
176 | ||
177 | static inline void set_be_option_rep(NBDOptionReply *rep, uint32_t option, | |
178 | uint32_t type, uint32_t length) | |
179 | { | |
180 | stq_be_p(&rep->magic, NBD_REP_MAGIC); | |
181 | stl_be_p(&rep->option, option); | |
182 | stl_be_p(&rep->type, type); | |
183 | stl_be_p(&rep->length, length); | |
184 | } | |
185 | ||
186 | /* Send a reply header, including length, but no payload. | |
187 | * Return -errno on error, 0 on success. */ | |
188 | static int nbd_negotiate_send_rep_len(NBDClient *client, uint32_t type, | |
189 | uint32_t len, Error **errp) | |
190 | { | |
191 | NBDOptionReply rep; | |
192 | ||
193 | trace_nbd_negotiate_send_rep_len(client->opt, nbd_opt_lookup(client->opt), | |
194 | type, nbd_rep_lookup(type), len); | |
195 | ||
196 | assert(len < NBD_MAX_BUFFER_SIZE); | |
197 | ||
198 | set_be_option_rep(&rep, client->opt, type, len); | |
199 | return nbd_write(client->ioc, &rep, sizeof(rep), errp); | |
200 | } | |
201 | ||
202 | /* Send a reply header with default 0 length. | |
203 | * Return -errno on error, 0 on success. */ | |
204 | static int nbd_negotiate_send_rep(NBDClient *client, uint32_t type, | |
205 | Error **errp) | |
206 | { | |
207 | return nbd_negotiate_send_rep_len(client, type, 0, errp); | |
208 | } | |
209 | ||
210 | /* Send an error reply. | |
211 | * Return -errno on error, 0 on success. */ | |
212 | static int GCC_FMT_ATTR(4, 0) | |
213 | nbd_negotiate_send_rep_verr(NBDClient *client, uint32_t type, | |
214 | Error **errp, const char *fmt, va_list va) | |
215 | { | |
216 | ERRP_GUARD(); | |
217 | g_autofree char *msg = NULL; | |
218 | int ret; | |
219 | size_t len; | |
220 | ||
221 | msg = g_strdup_vprintf(fmt, va); | |
222 | len = strlen(msg); | |
223 | assert(len < NBD_MAX_STRING_SIZE); | |
224 | trace_nbd_negotiate_send_rep_err(msg); | |
225 | ret = nbd_negotiate_send_rep_len(client, type, len, errp); | |
226 | if (ret < 0) { | |
227 | return ret; | |
228 | } | |
229 | if (nbd_write(client->ioc, msg, len, errp) < 0) { | |
230 | error_prepend(errp, "write failed (error message): "); | |
231 | return -EIO; | |
232 | } | |
233 | ||
234 | return 0; | |
235 | } | |
236 | ||
237 | /* | |
238 | * Return a malloc'd copy of @name suitable for use in an error reply. | |
239 | */ | |
240 | static char * | |
241 | nbd_sanitize_name(const char *name) | |
242 | { | |
243 | if (strnlen(name, 80) < 80) { | |
244 | return g_strdup(name); | |
245 | } | |
246 | /* XXX Should we also try to sanitize any control characters? */ | |
247 | return g_strdup_printf("%.80s...", name); | |
248 | } | |
249 | ||
250 | /* Send an error reply. | |
251 | * Return -errno on error, 0 on success. */ | |
252 | static int GCC_FMT_ATTR(4, 5) | |
253 | nbd_negotiate_send_rep_err(NBDClient *client, uint32_t type, | |
254 | Error **errp, const char *fmt, ...) | |
255 | { | |
256 | va_list va; | |
257 | int ret; | |
258 | ||
259 | va_start(va, fmt); | |
260 | ret = nbd_negotiate_send_rep_verr(client, type, errp, fmt, va); | |
261 | va_end(va); | |
262 | return ret; | |
263 | } | |
264 | ||
265 | /* Drop remainder of the current option, and send a reply with the | |
266 | * given error type and message. Return -errno on read or write | |
267 | * failure; or 0 if connection is still live. */ | |
268 | static int GCC_FMT_ATTR(4, 0) | |
269 | nbd_opt_vdrop(NBDClient *client, uint32_t type, Error **errp, | |
270 | const char *fmt, va_list va) | |
271 | { | |
272 | int ret = nbd_drop(client->ioc, client->optlen, errp); | |
273 | ||
274 | client->optlen = 0; | |
275 | if (!ret) { | |
276 | ret = nbd_negotiate_send_rep_verr(client, type, errp, fmt, va); | |
277 | } | |
278 | return ret; | |
279 | } | |
280 | ||
281 | static int GCC_FMT_ATTR(4, 5) | |
282 | nbd_opt_drop(NBDClient *client, uint32_t type, Error **errp, | |
283 | const char *fmt, ...) | |
284 | { | |
285 | int ret; | |
286 | va_list va; | |
287 | ||
288 | va_start(va, fmt); | |
289 | ret = nbd_opt_vdrop(client, type, errp, fmt, va); | |
290 | va_end(va); | |
291 | ||
292 | return ret; | |
293 | } | |
294 | ||
295 | static int GCC_FMT_ATTR(3, 4) | |
296 | nbd_opt_invalid(NBDClient *client, Error **errp, const char *fmt, ...) | |
297 | { | |
298 | int ret; | |
299 | va_list va; | |
300 | ||
301 | va_start(va, fmt); | |
302 | ret = nbd_opt_vdrop(client, NBD_REP_ERR_INVALID, errp, fmt, va); | |
303 | va_end(va); | |
304 | ||
305 | return ret; | |
306 | } | |
307 | ||
308 | /* Read size bytes from the unparsed payload of the current option. | |
309 | * Return -errno on I/O error, 0 if option was completely handled by | |
310 | * sending a reply about inconsistent lengths, or 1 on success. */ | |
311 | static int nbd_opt_read(NBDClient *client, void *buffer, size_t size, | |
312 | Error **errp) | |
313 | { | |
314 | if (size > client->optlen) { | |
315 | return nbd_opt_invalid(client, errp, | |
316 | "Inconsistent lengths in option %s", | |
317 | nbd_opt_lookup(client->opt)); | |
318 | } | |
319 | client->optlen -= size; | |
320 | return qio_channel_read_all(client->ioc, buffer, size, errp) < 0 ? -EIO : 1; | |
321 | } | |
322 | ||
323 | /* Drop size bytes from the unparsed payload of the current option. | |
324 | * Return -errno on I/O error, 0 if option was completely handled by | |
325 | * sending a reply about inconsistent lengths, or 1 on success. */ | |
326 | static int nbd_opt_skip(NBDClient *client, size_t size, Error **errp) | |
327 | { | |
328 | if (size > client->optlen) { | |
329 | return nbd_opt_invalid(client, errp, | |
330 | "Inconsistent lengths in option %s", | |
331 | nbd_opt_lookup(client->opt)); | |
332 | } | |
333 | client->optlen -= size; | |
334 | return nbd_drop(client->ioc, size, errp) < 0 ? -EIO : 1; | |
335 | } | |
336 | ||
337 | /* nbd_opt_read_name | |
338 | * | |
339 | * Read a string with the format: | |
340 | * uint32_t len (<= NBD_MAX_STRING_SIZE) | |
341 | * len bytes string (not 0-terminated) | |
342 | * | |
343 | * On success, @name will be allocated. | |
344 | * If @length is non-null, it will be set to the actual string length. | |
345 | * | |
346 | * Return -errno on I/O error, 0 if option was completely handled by | |
347 | * sending a reply about inconsistent lengths, or 1 on success. | |
348 | */ | |
349 | static int nbd_opt_read_name(NBDClient *client, char **name, uint32_t *length, | |
350 | Error **errp) | |
351 | { | |
352 | int ret; | |
353 | uint32_t len; | |
354 | g_autofree char *local_name = NULL; | |
355 | ||
356 | *name = NULL; | |
357 | ret = nbd_opt_read(client, &len, sizeof(len), errp); | |
358 | if (ret <= 0) { | |
359 | return ret; | |
360 | } | |
361 | len = cpu_to_be32(len); | |
362 | ||
363 | if (len > NBD_MAX_STRING_SIZE) { | |
364 | return nbd_opt_invalid(client, errp, | |
365 | "Invalid name length: %" PRIu32, len); | |
366 | } | |
367 | ||
368 | local_name = g_malloc(len + 1); | |
369 | ret = nbd_opt_read(client, local_name, len, errp); | |
370 | if (ret <= 0) { | |
371 | return ret; | |
372 | } | |
373 | local_name[len] = '\0'; | |
374 | ||
375 | if (length) { | |
376 | *length = len; | |
377 | } | |
378 | *name = g_steal_pointer(&local_name); | |
379 | ||
380 | return 1; | |
381 | } | |
382 | ||
383 | /* Send a single NBD_REP_SERVER reply to NBD_OPT_LIST, including payload. | |
384 | * Return -errno on error, 0 on success. */ | |
385 | static int nbd_negotiate_send_rep_list(NBDClient *client, NBDExport *exp, | |
386 | Error **errp) | |
387 | { | |
388 | ERRP_GUARD(); | |
389 | size_t name_len, desc_len; | |
390 | uint32_t len; | |
391 | const char *name = exp->name ? exp->name : ""; | |
392 | const char *desc = exp->description ? exp->description : ""; | |
393 | QIOChannel *ioc = client->ioc; | |
394 | int ret; | |
395 | ||
396 | trace_nbd_negotiate_send_rep_list(name, desc); | |
397 | name_len = strlen(name); | |
398 | desc_len = strlen(desc); | |
399 | assert(name_len <= NBD_MAX_STRING_SIZE && desc_len <= NBD_MAX_STRING_SIZE); | |
400 | len = name_len + desc_len + sizeof(len); | |
401 | ret = nbd_negotiate_send_rep_len(client, NBD_REP_SERVER, len, errp); | |
402 | if (ret < 0) { | |
403 | return ret; | |
404 | } | |
405 | ||
406 | len = cpu_to_be32(name_len); | |
407 | if (nbd_write(ioc, &len, sizeof(len), errp) < 0) { | |
408 | error_prepend(errp, "write failed (name length): "); | |
409 | return -EINVAL; | |
410 | } | |
411 | ||
412 | if (nbd_write(ioc, name, name_len, errp) < 0) { | |
413 | error_prepend(errp, "write failed (name buffer): "); | |
414 | return -EINVAL; | |
415 | } | |
416 | ||
417 | if (nbd_write(ioc, desc, desc_len, errp) < 0) { | |
418 | error_prepend(errp, "write failed (description buffer): "); | |
419 | return -EINVAL; | |
420 | } | |
421 | ||
422 | return 0; | |
423 | } | |
424 | ||
425 | /* Process the NBD_OPT_LIST command, with a potential series of replies. | |
426 | * Return -errno on error, 0 on success. */ | |
427 | static int nbd_negotiate_handle_list(NBDClient *client, Error **errp) | |
428 | { | |
429 | NBDExport *exp; | |
430 | assert(client->opt == NBD_OPT_LIST); | |
431 | ||
432 | /* For each export, send a NBD_REP_SERVER reply. */ | |
433 | QTAILQ_FOREACH(exp, &exports, next) { | |
434 | if (nbd_negotiate_send_rep_list(client, exp, errp)) { | |
435 | return -EINVAL; | |
436 | } | |
437 | } | |
438 | /* Finish with a NBD_REP_ACK. */ | |
439 | return nbd_negotiate_send_rep(client, NBD_REP_ACK, errp); | |
440 | } | |
441 | ||
442 | static void nbd_check_meta_export(NBDClient *client) | |
443 | { | |
444 | client->export_meta.valid &= client->exp == client->export_meta.exp; | |
445 | } | |
446 | ||
447 | /* Send a reply to NBD_OPT_EXPORT_NAME. | |
448 | * Return -errno on error, 0 on success. */ | |
449 | static int nbd_negotiate_handle_export_name(NBDClient *client, bool no_zeroes, | |
450 | Error **errp) | |
451 | { | |
452 | ERRP_GUARD(); | |
453 | g_autofree char *name = NULL; | |
454 | char buf[NBD_REPLY_EXPORT_NAME_SIZE] = ""; | |
455 | size_t len; | |
456 | int ret; | |
457 | uint16_t myflags; | |
458 | ||
459 | /* Client sends: | |
460 | [20 .. xx] export name (length bytes) | |
461 | Server replies: | |
462 | [ 0 .. 7] size | |
463 | [ 8 .. 9] export flags | |
464 | [10 .. 133] reserved (0) [unless no_zeroes] | |
465 | */ | |
466 | trace_nbd_negotiate_handle_export_name(); | |
467 | if (client->optlen > NBD_MAX_STRING_SIZE) { | |
468 | error_setg(errp, "Bad length received"); | |
469 | return -EINVAL; | |
470 | } | |
471 | name = g_malloc(client->optlen + 1); | |
472 | if (nbd_read(client->ioc, name, client->optlen, "export name", errp) < 0) { | |
473 | return -EIO; | |
474 | } | |
475 | name[client->optlen] = '\0'; | |
476 | client->optlen = 0; | |
477 | ||
478 | trace_nbd_negotiate_handle_export_name_request(name); | |
479 | ||
480 | client->exp = nbd_export_find(name); | |
481 | if (!client->exp) { | |
482 | error_setg(errp, "export not found"); | |
483 | return -EINVAL; | |
484 | } | |
485 | ||
486 | myflags = client->exp->nbdflags; | |
487 | if (client->structured_reply) { | |
488 | myflags |= NBD_FLAG_SEND_DF; | |
489 | } | |
490 | trace_nbd_negotiate_new_style_size_flags(client->exp->size, myflags); | |
491 | stq_be_p(buf, client->exp->size); | |
492 | stw_be_p(buf + 8, myflags); | |
493 | len = no_zeroes ? 10 : sizeof(buf); | |
494 | ret = nbd_write(client->ioc, buf, len, errp); | |
495 | if (ret < 0) { | |
496 | error_prepend(errp, "write failed: "); | |
497 | return ret; | |
498 | } | |
499 | ||
500 | QTAILQ_INSERT_TAIL(&client->exp->clients, client, next); | |
501 | nbd_export_get(client->exp); | |
502 | nbd_check_meta_export(client); | |
503 | ||
504 | return 0; | |
505 | } | |
506 | ||
507 | /* Send a single NBD_REP_INFO, with a buffer @buf of @length bytes. | |
508 | * The buffer does NOT include the info type prefix. | |
509 | * Return -errno on error, 0 if ready to send more. */ | |
510 | static int nbd_negotiate_send_info(NBDClient *client, | |
511 | uint16_t info, uint32_t length, void *buf, | |
512 | Error **errp) | |
513 | { | |
514 | int rc; | |
515 | ||
516 | trace_nbd_negotiate_send_info(info, nbd_info_lookup(info), length); | |
517 | rc = nbd_negotiate_send_rep_len(client, NBD_REP_INFO, | |
518 | sizeof(info) + length, errp); | |
519 | if (rc < 0) { | |
520 | return rc; | |
521 | } | |
522 | info = cpu_to_be16(info); | |
523 | if (nbd_write(client->ioc, &info, sizeof(info), errp) < 0) { | |
524 | return -EIO; | |
525 | } | |
526 | if (nbd_write(client->ioc, buf, length, errp) < 0) { | |
527 | return -EIO; | |
528 | } | |
529 | return 0; | |
530 | } | |
531 | ||
532 | /* nbd_reject_length: Handle any unexpected payload. | |
533 | * @fatal requests that we quit talking to the client, even if we are able | |
534 | * to successfully send an error reply. | |
535 | * Return: | |
536 | * -errno transmission error occurred or @fatal was requested, errp is set | |
537 | * 0 error message successfully sent to client, errp is not set | |
538 | */ | |
539 | static int nbd_reject_length(NBDClient *client, bool fatal, Error **errp) | |
540 | { | |
541 | int ret; | |
542 | ||
543 | assert(client->optlen); | |
544 | ret = nbd_opt_invalid(client, errp, "option '%s' has unexpected length", | |
545 | nbd_opt_lookup(client->opt)); | |
546 | if (fatal && !ret) { | |
547 | error_setg(errp, "option '%s' has unexpected length", | |
548 | nbd_opt_lookup(client->opt)); | |
549 | return -EINVAL; | |
550 | } | |
551 | return ret; | |
552 | } | |
553 | ||
554 | /* Handle NBD_OPT_INFO and NBD_OPT_GO. | |
555 | * Return -errno on error, 0 if ready for next option, and 1 to move | |
556 | * into transmission phase. */ | |
557 | static int nbd_negotiate_handle_info(NBDClient *client, Error **errp) | |
558 | { | |
559 | int rc; | |
560 | g_autofree char *name = NULL; | |
561 | NBDExport *exp; | |
562 | uint16_t requests; | |
563 | uint16_t request; | |
564 | uint32_t namelen; | |
565 | bool sendname = false; | |
566 | bool blocksize = false; | |
567 | uint32_t sizes[3]; | |
568 | char buf[sizeof(uint64_t) + sizeof(uint16_t)]; | |
569 | uint32_t check_align = 0; | |
570 | uint16_t myflags; | |
571 | ||
572 | /* Client sends: | |
573 | 4 bytes: L, name length (can be 0) | |
574 | L bytes: export name | |
575 | 2 bytes: N, number of requests (can be 0) | |
576 | N * 2 bytes: N requests | |
577 | */ | |
578 | rc = nbd_opt_read_name(client, &name, &namelen, errp); | |
579 | if (rc <= 0) { | |
580 | return rc; | |
581 | } | |
582 | trace_nbd_negotiate_handle_export_name_request(name); | |
583 | ||
584 | rc = nbd_opt_read(client, &requests, sizeof(requests), errp); | |
585 | if (rc <= 0) { | |
586 | return rc; | |
587 | } | |
588 | requests = be16_to_cpu(requests); | |
589 | trace_nbd_negotiate_handle_info_requests(requests); | |
590 | while (requests--) { | |
591 | rc = nbd_opt_read(client, &request, sizeof(request), errp); | |
592 | if (rc <= 0) { | |
593 | return rc; | |
594 | } | |
595 | request = be16_to_cpu(request); | |
596 | trace_nbd_negotiate_handle_info_request(request, | |
597 | nbd_info_lookup(request)); | |
598 | /* We care about NBD_INFO_NAME and NBD_INFO_BLOCK_SIZE; | |
599 | * everything else is either a request we don't know or | |
600 | * something we send regardless of request */ | |
601 | switch (request) { | |
602 | case NBD_INFO_NAME: | |
603 | sendname = true; | |
604 | break; | |
605 | case NBD_INFO_BLOCK_SIZE: | |
606 | blocksize = true; | |
607 | break; | |
608 | } | |
609 | } | |
610 | if (client->optlen) { | |
611 | return nbd_reject_length(client, false, errp); | |
612 | } | |
613 | ||
614 | exp = nbd_export_find(name); | |
615 | if (!exp) { | |
616 | g_autofree char *sane_name = nbd_sanitize_name(name); | |
617 | ||
618 | return nbd_negotiate_send_rep_err(client, NBD_REP_ERR_UNKNOWN, | |
619 | errp, "export '%s' not present", | |
620 | sane_name); | |
621 | } | |
622 | ||
623 | /* Don't bother sending NBD_INFO_NAME unless client requested it */ | |
624 | if (sendname) { | |
625 | rc = nbd_negotiate_send_info(client, NBD_INFO_NAME, namelen, name, | |
626 | errp); | |
627 | if (rc < 0) { | |
628 | return rc; | |
629 | } | |
630 | } | |
631 | ||
632 | /* Send NBD_INFO_DESCRIPTION only if available, regardless of | |
633 | * client request */ | |
634 | if (exp->description) { | |
635 | size_t len = strlen(exp->description); | |
636 | ||
637 | assert(len <= NBD_MAX_STRING_SIZE); | |
638 | rc = nbd_negotiate_send_info(client, NBD_INFO_DESCRIPTION, | |
639 | len, exp->description, errp); | |
640 | if (rc < 0) { | |
641 | return rc; | |
642 | } | |
643 | } | |
644 | ||
645 | /* Send NBD_INFO_BLOCK_SIZE always, but tweak the minimum size | |
646 | * according to whether the client requested it, and according to | |
647 | * whether this is OPT_INFO or OPT_GO. */ | |
648 | /* minimum - 1 for back-compat, or actual if client will obey it. */ | |
649 | if (client->opt == NBD_OPT_INFO || blocksize) { | |
650 | check_align = sizes[0] = blk_get_request_alignment(exp->blk); | |
651 | } else { | |
652 | sizes[0] = 1; | |
653 | } | |
654 | assert(sizes[0] <= NBD_MAX_BUFFER_SIZE); | |
655 | /* preferred - Hard-code to 4096 for now. | |
656 | * TODO: is blk_bs(blk)->bl.opt_transfer appropriate? */ | |
657 | sizes[1] = MAX(4096, sizes[0]); | |
658 | /* maximum - At most 32M, but smaller as appropriate. */ | |
659 | sizes[2] = MIN(blk_get_max_transfer(exp->blk), NBD_MAX_BUFFER_SIZE); | |
660 | trace_nbd_negotiate_handle_info_block_size(sizes[0], sizes[1], sizes[2]); | |
661 | sizes[0] = cpu_to_be32(sizes[0]); | |
662 | sizes[1] = cpu_to_be32(sizes[1]); | |
663 | sizes[2] = cpu_to_be32(sizes[2]); | |
664 | rc = nbd_negotiate_send_info(client, NBD_INFO_BLOCK_SIZE, | |
665 | sizeof(sizes), sizes, errp); | |
666 | if (rc < 0) { | |
667 | return rc; | |
668 | } | |
669 | ||
670 | /* Send NBD_INFO_EXPORT always */ | |
671 | myflags = exp->nbdflags; | |
672 | if (client->structured_reply) { | |
673 | myflags |= NBD_FLAG_SEND_DF; | |
674 | } | |
675 | trace_nbd_negotiate_new_style_size_flags(exp->size, myflags); | |
676 | stq_be_p(buf, exp->size); | |
677 | stw_be_p(buf + 8, myflags); | |
678 | rc = nbd_negotiate_send_info(client, NBD_INFO_EXPORT, | |
679 | sizeof(buf), buf, errp); | |
680 | if (rc < 0) { | |
681 | return rc; | |
682 | } | |
683 | ||
684 | /* | |
685 | * If the client is just asking for NBD_OPT_INFO, but forgot to | |
686 | * request block sizes in a situation that would impact | |
687 | * performance, then return an error. But for NBD_OPT_GO, we | |
688 | * tolerate all clients, regardless of alignments. | |
689 | */ | |
690 | if (client->opt == NBD_OPT_INFO && !blocksize && | |
691 | blk_get_request_alignment(exp->blk) > 1) { | |
692 | return nbd_negotiate_send_rep_err(client, | |
693 | NBD_REP_ERR_BLOCK_SIZE_REQD, | |
694 | errp, | |
695 | "request NBD_INFO_BLOCK_SIZE to " | |
696 | "use this export"); | |
697 | } | |
698 | ||
699 | /* Final reply */ | |
700 | rc = nbd_negotiate_send_rep(client, NBD_REP_ACK, errp); | |
701 | if (rc < 0) { | |
702 | return rc; | |
703 | } | |
704 | ||
705 | if (client->opt == NBD_OPT_GO) { | |
706 | client->exp = exp; | |
707 | client->check_align = check_align; | |
708 | QTAILQ_INSERT_TAIL(&client->exp->clients, client, next); | |
709 | nbd_export_get(client->exp); | |
710 | nbd_check_meta_export(client); | |
711 | rc = 1; | |
712 | } | |
713 | return rc; | |
714 | } | |
715 | ||
716 | ||
717 | /* Handle NBD_OPT_STARTTLS. Return NULL to drop connection, or else the | |
718 | * new channel for all further (now-encrypted) communication. */ | |
719 | static QIOChannel *nbd_negotiate_handle_starttls(NBDClient *client, | |
720 | Error **errp) | |
721 | { | |
722 | QIOChannel *ioc; | |
723 | QIOChannelTLS *tioc; | |
724 | struct NBDTLSHandshakeData data = { 0 }; | |
725 | ||
726 | assert(client->opt == NBD_OPT_STARTTLS); | |
727 | ||
728 | trace_nbd_negotiate_handle_starttls(); | |
729 | ioc = client->ioc; | |
730 | ||
731 | if (nbd_negotiate_send_rep(client, NBD_REP_ACK, errp) < 0) { | |
732 | return NULL; | |
733 | } | |
734 | ||
735 | tioc = qio_channel_tls_new_server(ioc, | |
736 | client->tlscreds, | |
737 | client->tlsauthz, | |
738 | errp); | |
739 | if (!tioc) { | |
740 | return NULL; | |
741 | } | |
742 | ||
743 | qio_channel_set_name(QIO_CHANNEL(tioc), "nbd-server-tls"); | |
744 | trace_nbd_negotiate_handle_starttls_handshake(); | |
745 | data.loop = g_main_loop_new(g_main_context_default(), FALSE); | |
746 | qio_channel_tls_handshake(tioc, | |
747 | nbd_tls_handshake, | |
748 | &data, | |
749 | NULL, | |
750 | NULL); | |
751 | ||
752 | if (!data.complete) { | |
753 | g_main_loop_run(data.loop); | |
754 | } | |
755 | g_main_loop_unref(data.loop); | |
756 | if (data.error) { | |
757 | object_unref(OBJECT(tioc)); | |
758 | error_propagate(errp, data.error); | |
759 | return NULL; | |
760 | } | |
761 | ||
762 | return QIO_CHANNEL(tioc); | |
763 | } | |
764 | ||
765 | /* nbd_negotiate_send_meta_context | |
766 | * | |
767 | * Send one chunk of reply to NBD_OPT_{LIST,SET}_META_CONTEXT | |
768 | * | |
769 | * For NBD_OPT_LIST_META_CONTEXT @context_id is ignored, 0 is used instead. | |
770 | */ | |
771 | static int nbd_negotiate_send_meta_context(NBDClient *client, | |
772 | const char *context, | |
773 | uint32_t context_id, | |
774 | Error **errp) | |
775 | { | |
776 | NBDOptionReplyMetaContext opt; | |
777 | struct iovec iov[] = { | |
778 | {.iov_base = &opt, .iov_len = sizeof(opt)}, | |
779 | {.iov_base = (void *)context, .iov_len = strlen(context)} | |
780 | }; | |
781 | ||
782 | assert(iov[1].iov_len <= NBD_MAX_STRING_SIZE); | |
783 | if (client->opt == NBD_OPT_LIST_META_CONTEXT) { | |
784 | context_id = 0; | |
785 | } | |
786 | ||
787 | trace_nbd_negotiate_meta_query_reply(context, context_id); | |
788 | set_be_option_rep(&opt.h, client->opt, NBD_REP_META_CONTEXT, | |
789 | sizeof(opt) - sizeof(opt.h) + iov[1].iov_len); | |
790 | stl_be_p(&opt.context_id, context_id); | |
791 | ||
792 | return qio_channel_writev_all(client->ioc, iov, 2, errp) < 0 ? -EIO : 0; | |
793 | } | |
794 | ||
795 | /* Read strlen(@pattern) bytes, and set @match to true if they match @pattern. | |
796 | * @match is never set to false. | |
797 | * | |
798 | * Return -errno on I/O error, 0 if option was completely handled by | |
799 | * sending a reply about inconsistent lengths, or 1 on success. | |
800 | * | |
801 | * Note: return code = 1 doesn't mean that we've read exactly @pattern. | |
802 | * It only means that there are no errors. | |
803 | */ | |
804 | static int nbd_meta_pattern(NBDClient *client, const char *pattern, bool *match, | |
805 | Error **errp) | |
806 | { | |
807 | int ret; | |
808 | char *query; | |
809 | size_t len = strlen(pattern); | |
810 | ||
811 | assert(len); | |
812 | ||
813 | query = g_malloc(len); | |
814 | ret = nbd_opt_read(client, query, len, errp); | |
815 | if (ret <= 0) { | |
816 | g_free(query); | |
817 | return ret; | |
818 | } | |
819 | ||
820 | if (strncmp(query, pattern, len) == 0) { | |
821 | trace_nbd_negotiate_meta_query_parse(pattern); | |
822 | *match = true; | |
823 | } else { | |
824 | trace_nbd_negotiate_meta_query_skip("pattern not matched"); | |
825 | } | |
826 | g_free(query); | |
827 | ||
828 | return 1; | |
829 | } | |
830 | ||
831 | /* | |
832 | * Read @len bytes, and set @match to true if they match @pattern, or if @len | |
833 | * is 0 and the client is performing _LIST_. @match is never set to false. | |
834 | * | |
835 | * Return -errno on I/O error, 0 if option was completely handled by | |
836 | * sending a reply about inconsistent lengths, or 1 on success. | |
837 | * | |
838 | * Note: return code = 1 doesn't mean that we've read exactly @pattern. | |
839 | * It only means that there are no errors. | |
840 | */ | |
841 | static int nbd_meta_empty_or_pattern(NBDClient *client, const char *pattern, | |
842 | uint32_t len, bool *match, Error **errp) | |
843 | { | |
844 | if (len == 0) { | |
845 | if (client->opt == NBD_OPT_LIST_META_CONTEXT) { | |
846 | *match = true; | |
847 | } | |
848 | trace_nbd_negotiate_meta_query_parse("empty"); | |
849 | return 1; | |
850 | } | |
851 | ||
852 | if (len != strlen(pattern)) { | |
853 | trace_nbd_negotiate_meta_query_skip("different lengths"); | |
854 | return nbd_opt_skip(client, len, errp); | |
855 | } | |
856 | ||
857 | return nbd_meta_pattern(client, pattern, match, errp); | |
858 | } | |
859 | ||
860 | /* nbd_meta_base_query | |
861 | * | |
862 | * Handle queries to 'base' namespace. For now, only the base:allocation | |
863 | * context is available. 'len' is the amount of text remaining to be read from | |
864 | * the current name, after the 'base:' portion has been stripped. | |
865 | * | |
866 | * Return -errno on I/O error, 0 if option was completely handled by | |
867 | * sending a reply about inconsistent lengths, or 1 on success. | |
868 | */ | |
869 | static int nbd_meta_base_query(NBDClient *client, NBDExportMetaContexts *meta, | |
870 | uint32_t len, Error **errp) | |
871 | { | |
872 | return nbd_meta_empty_or_pattern(client, "allocation", len, | |
873 | &meta->base_allocation, errp); | |
874 | } | |
875 | ||
876 | /* nbd_meta_bitmap_query | |
877 | * | |
878 | * Handle query to 'qemu:' namespace. | |
879 | * @len is the amount of text remaining to be read from the current name, after | |
880 | * the 'qemu:' portion has been stripped. | |
881 | * | |
882 | * Return -errno on I/O error, 0 if option was completely handled by | |
883 | * sending a reply about inconsistent lengths, or 1 on success. */ | |
884 | static int nbd_meta_qemu_query(NBDClient *client, NBDExportMetaContexts *meta, | |
885 | uint32_t len, Error **errp) | |
886 | { | |
887 | bool dirty_bitmap = false; | |
888 | size_t dirty_bitmap_len = strlen("dirty-bitmap:"); | |
889 | int ret; | |
890 | ||
891 | if (!meta->exp->export_bitmap) { | |
892 | trace_nbd_negotiate_meta_query_skip("no dirty-bitmap exported"); | |
893 | return nbd_opt_skip(client, len, errp); | |
894 | } | |
895 | ||
896 | if (len == 0) { | |
897 | if (client->opt == NBD_OPT_LIST_META_CONTEXT) { | |
898 | meta->bitmap = true; | |
899 | } | |
900 | trace_nbd_negotiate_meta_query_parse("empty"); | |
901 | return 1; | |
902 | } | |
903 | ||
904 | if (len < dirty_bitmap_len) { | |
905 | trace_nbd_negotiate_meta_query_skip("not dirty-bitmap:"); | |
906 | return nbd_opt_skip(client, len, errp); | |
907 | } | |
908 | ||
909 | len -= dirty_bitmap_len; | |
910 | ret = nbd_meta_pattern(client, "dirty-bitmap:", &dirty_bitmap, errp); | |
911 | if (ret <= 0) { | |
912 | return ret; | |
913 | } | |
914 | if (!dirty_bitmap) { | |
915 | trace_nbd_negotiate_meta_query_skip("not dirty-bitmap:"); | |
916 | return nbd_opt_skip(client, len, errp); | |
917 | } | |
918 | ||
919 | trace_nbd_negotiate_meta_query_parse("dirty-bitmap:"); | |
920 | ||
921 | return nbd_meta_empty_or_pattern( | |
922 | client, meta->exp->export_bitmap_context + | |
923 | strlen("qemu:dirty_bitmap:"), len, &meta->bitmap, errp); | |
924 | } | |
925 | ||
926 | /* nbd_negotiate_meta_query | |
927 | * | |
928 | * Parse namespace name and call corresponding function to parse body of the | |
929 | * query. | |
930 | * | |
931 | * The only supported namespaces are 'base' and 'qemu'. | |
932 | * | |
933 | * The function aims not wasting time and memory to read long unknown namespace | |
934 | * names. | |
935 | * | |
936 | * Return -errno on I/O error, 0 if option was completely handled by | |
937 | * sending a reply about inconsistent lengths, or 1 on success. */ | |
938 | static int nbd_negotiate_meta_query(NBDClient *client, | |
939 | NBDExportMetaContexts *meta, Error **errp) | |
940 | { | |
941 | /* | |
942 | * Both 'qemu' and 'base' namespaces have length = 5 including a | |
943 | * colon. If another length namespace is later introduced, this | |
944 | * should certainly be refactored. | |
945 | */ | |
946 | int ret; | |
947 | size_t ns_len = 5; | |
948 | char ns[5]; | |
949 | uint32_t len; | |
950 | ||
951 | ret = nbd_opt_read(client, &len, sizeof(len), errp); | |
952 | if (ret <= 0) { | |
953 | return ret; | |
954 | } | |
955 | len = cpu_to_be32(len); | |
956 | ||
957 | if (len > NBD_MAX_STRING_SIZE) { | |
958 | trace_nbd_negotiate_meta_query_skip("length too long"); | |
959 | return nbd_opt_skip(client, len, errp); | |
960 | } | |
961 | if (len < ns_len) { | |
962 | trace_nbd_negotiate_meta_query_skip("length too short"); | |
963 | return nbd_opt_skip(client, len, errp); | |
964 | } | |
965 | ||
966 | len -= ns_len; | |
967 | ret = nbd_opt_read(client, ns, ns_len, errp); | |
968 | if (ret <= 0) { | |
969 | return ret; | |
970 | } | |
971 | ||
972 | if (!strncmp(ns, "base:", ns_len)) { | |
973 | trace_nbd_negotiate_meta_query_parse("base:"); | |
974 | return nbd_meta_base_query(client, meta, len, errp); | |
975 | } else if (!strncmp(ns, "qemu:", ns_len)) { | |
976 | trace_nbd_negotiate_meta_query_parse("qemu:"); | |
977 | return nbd_meta_qemu_query(client, meta, len, errp); | |
978 | } | |
979 | ||
980 | trace_nbd_negotiate_meta_query_skip("unknown namespace"); | |
981 | return nbd_opt_skip(client, len, errp); | |
982 | } | |
983 | ||
984 | /* nbd_negotiate_meta_queries | |
985 | * Handle NBD_OPT_LIST_META_CONTEXT and NBD_OPT_SET_META_CONTEXT | |
986 | * | |
987 | * Return -errno on I/O error, or 0 if option was completely handled. */ | |
988 | static int nbd_negotiate_meta_queries(NBDClient *client, | |
989 | NBDExportMetaContexts *meta, Error **errp) | |
990 | { | |
991 | int ret; | |
992 | g_autofree char *export_name = NULL; | |
993 | NBDExportMetaContexts local_meta; | |
994 | uint32_t nb_queries; | |
995 | int i; | |
996 | ||
997 | if (!client->structured_reply) { | |
998 | return nbd_opt_invalid(client, errp, | |
999 | "request option '%s' when structured reply " | |
1000 | "is not negotiated", | |
1001 | nbd_opt_lookup(client->opt)); | |
1002 | } | |
1003 | ||
1004 | if (client->opt == NBD_OPT_LIST_META_CONTEXT) { | |
1005 | /* Only change the caller's meta on SET. */ | |
1006 | meta = &local_meta; | |
1007 | } | |
1008 | ||
1009 | memset(meta, 0, sizeof(*meta)); | |
1010 | ||
1011 | ret = nbd_opt_read_name(client, &export_name, NULL, errp); | |
1012 | if (ret <= 0) { | |
1013 | return ret; | |
1014 | } | |
1015 | ||
1016 | meta->exp = nbd_export_find(export_name); | |
1017 | if (meta->exp == NULL) { | |
1018 | g_autofree char *sane_name = nbd_sanitize_name(export_name); | |
1019 | ||
1020 | return nbd_opt_drop(client, NBD_REP_ERR_UNKNOWN, errp, | |
1021 | "export '%s' not present", sane_name); | |
1022 | } | |
1023 | ||
1024 | ret = nbd_opt_read(client, &nb_queries, sizeof(nb_queries), errp); | |
1025 | if (ret <= 0) { | |
1026 | return ret; | |
1027 | } | |
1028 | nb_queries = cpu_to_be32(nb_queries); | |
1029 | trace_nbd_negotiate_meta_context(nbd_opt_lookup(client->opt), | |
1030 | export_name, nb_queries); | |
1031 | ||
1032 | if (client->opt == NBD_OPT_LIST_META_CONTEXT && !nb_queries) { | |
1033 | /* enable all known contexts */ | |
1034 | meta->base_allocation = true; | |
1035 | meta->bitmap = !!meta->exp->export_bitmap; | |
1036 | } else { | |
1037 | for (i = 0; i < nb_queries; ++i) { | |
1038 | ret = nbd_negotiate_meta_query(client, meta, errp); | |
1039 | if (ret <= 0) { | |
1040 | return ret; | |
1041 | } | |
1042 | } | |
1043 | } | |
1044 | ||
1045 | if (meta->base_allocation) { | |
1046 | ret = nbd_negotiate_send_meta_context(client, "base:allocation", | |
1047 | NBD_META_ID_BASE_ALLOCATION, | |
1048 | errp); | |
1049 | if (ret < 0) { | |
1050 | return ret; | |
1051 | } | |
1052 | } | |
1053 | ||
1054 | if (meta->bitmap) { | |
1055 | ret = nbd_negotiate_send_meta_context(client, | |
1056 | meta->exp->export_bitmap_context, | |
1057 | NBD_META_ID_DIRTY_BITMAP, | |
1058 | errp); | |
1059 | if (ret < 0) { | |
1060 | return ret; | |
1061 | } | |
1062 | } | |
1063 | ||
1064 | ret = nbd_negotiate_send_rep(client, NBD_REP_ACK, errp); | |
1065 | if (ret == 0) { | |
1066 | meta->valid = true; | |
1067 | } | |
1068 | ||
1069 | return ret; | |
1070 | } | |
1071 | ||
1072 | /* nbd_negotiate_options | |
1073 | * Process all NBD_OPT_* client option commands, during fixed newstyle | |
1074 | * negotiation. | |
1075 | * Return: | |
1076 | * -errno on error, errp is set | |
1077 | * 0 on successful negotiation, errp is not set | |
1078 | * 1 if client sent NBD_OPT_ABORT, i.e. on valid disconnect, | |
1079 | * errp is not set | |
1080 | */ | |
1081 | static int nbd_negotiate_options(NBDClient *client, Error **errp) | |
1082 | { | |
1083 | uint32_t flags; | |
1084 | bool fixedNewstyle = false; | |
1085 | bool no_zeroes = false; | |
1086 | ||
1087 | /* Client sends: | |
1088 | [ 0 .. 3] client flags | |
1089 | ||
1090 | Then we loop until NBD_OPT_EXPORT_NAME or NBD_OPT_GO: | |
1091 | [ 0 .. 7] NBD_OPTS_MAGIC | |
1092 | [ 8 .. 11] NBD option | |
1093 | [12 .. 15] Data length | |
1094 | ... Rest of request | |
1095 | ||
1096 | [ 0 .. 7] NBD_OPTS_MAGIC | |
1097 | [ 8 .. 11] Second NBD option | |
1098 | [12 .. 15] Data length | |
1099 | ... Rest of request | |
1100 | */ | |
1101 | ||
1102 | if (nbd_read32(client->ioc, &flags, "flags", errp) < 0) { | |
1103 | return -EIO; | |
1104 | } | |
1105 | trace_nbd_negotiate_options_flags(flags); | |
1106 | if (flags & NBD_FLAG_C_FIXED_NEWSTYLE) { | |
1107 | fixedNewstyle = true; | |
1108 | flags &= ~NBD_FLAG_C_FIXED_NEWSTYLE; | |
1109 | } | |
1110 | if (flags & NBD_FLAG_C_NO_ZEROES) { | |
1111 | no_zeroes = true; | |
1112 | flags &= ~NBD_FLAG_C_NO_ZEROES; | |
1113 | } | |
1114 | if (flags != 0) { | |
1115 | error_setg(errp, "Unknown client flags 0x%" PRIx32 " received", flags); | |
1116 | return -EINVAL; | |
1117 | } | |
1118 | ||
1119 | while (1) { | |
1120 | int ret; | |
1121 | uint32_t option, length; | |
1122 | uint64_t magic; | |
1123 | ||
1124 | if (nbd_read64(client->ioc, &magic, "opts magic", errp) < 0) { | |
1125 | return -EINVAL; | |
1126 | } | |
1127 | trace_nbd_negotiate_options_check_magic(magic); | |
1128 | if (magic != NBD_OPTS_MAGIC) { | |
1129 | error_setg(errp, "Bad magic received"); | |
1130 | return -EINVAL; | |
1131 | } | |
1132 | ||
1133 | if (nbd_read32(client->ioc, &option, "option", errp) < 0) { | |
1134 | return -EINVAL; | |
1135 | } | |
1136 | client->opt = option; | |
1137 | ||
1138 | if (nbd_read32(client->ioc, &length, "option length", errp) < 0) { | |
1139 | return -EINVAL; | |
1140 | } | |
1141 | assert(!client->optlen); | |
1142 | client->optlen = length; | |
1143 | ||
1144 | if (length > NBD_MAX_BUFFER_SIZE) { | |
1145 | error_setg(errp, "len (%" PRIu32" ) is larger than max len (%u)", | |
1146 | length, NBD_MAX_BUFFER_SIZE); | |
1147 | return -EINVAL; | |
1148 | } | |
1149 | ||
1150 | trace_nbd_negotiate_options_check_option(option, | |
1151 | nbd_opt_lookup(option)); | |
1152 | if (client->tlscreds && | |
1153 | client->ioc == (QIOChannel *)client->sioc) { | |
1154 | QIOChannel *tioc; | |
1155 | if (!fixedNewstyle) { | |
1156 | error_setg(errp, "Unsupported option 0x%" PRIx32, option); | |
1157 | return -EINVAL; | |
1158 | } | |
1159 | switch (option) { | |
1160 | case NBD_OPT_STARTTLS: | |
1161 | if (length) { | |
1162 | /* Unconditionally drop the connection if the client | |
1163 | * can't start a TLS negotiation correctly */ | |
1164 | return nbd_reject_length(client, true, errp); | |
1165 | } | |
1166 | tioc = nbd_negotiate_handle_starttls(client, errp); | |
1167 | if (!tioc) { | |
1168 | return -EIO; | |
1169 | } | |
1170 | ret = 0; | |
1171 | object_unref(OBJECT(client->ioc)); | |
1172 | client->ioc = QIO_CHANNEL(tioc); | |
1173 | break; | |
1174 | ||
1175 | case NBD_OPT_EXPORT_NAME: | |
1176 | /* No way to return an error to client, so drop connection */ | |
1177 | error_setg(errp, "Option 0x%x not permitted before TLS", | |
1178 | option); | |
1179 | return -EINVAL; | |
1180 | ||
1181 | default: | |
1182 | /* Let the client keep trying, unless they asked to | |
1183 | * quit. Always try to give an error back to the | |
1184 | * client; but when replying to OPT_ABORT, be aware | |
1185 | * that the client may hang up before receiving the | |
1186 | * error, in which case we are fine ignoring the | |
1187 | * resulting EPIPE. */ | |
1188 | ret = nbd_opt_drop(client, NBD_REP_ERR_TLS_REQD, | |
1189 | option == NBD_OPT_ABORT ? NULL : errp, | |
1190 | "Option 0x%" PRIx32 | |
1191 | " not permitted before TLS", option); | |
1192 | if (option == NBD_OPT_ABORT) { | |
1193 | return 1; | |
1194 | } | |
1195 | break; | |
1196 | } | |
1197 | } else if (fixedNewstyle) { | |
1198 | switch (option) { | |
1199 | case NBD_OPT_LIST: | |
1200 | if (length) { | |
1201 | ret = nbd_reject_length(client, false, errp); | |
1202 | } else { | |
1203 | ret = nbd_negotiate_handle_list(client, errp); | |
1204 | } | |
1205 | break; | |
1206 | ||
1207 | case NBD_OPT_ABORT: | |
1208 | /* NBD spec says we must try to reply before | |
1209 | * disconnecting, but that we must also tolerate | |
1210 | * guests that don't wait for our reply. */ | |
1211 | nbd_negotiate_send_rep(client, NBD_REP_ACK, NULL); | |
1212 | return 1; | |
1213 | ||
1214 | case NBD_OPT_EXPORT_NAME: | |
1215 | return nbd_negotiate_handle_export_name(client, no_zeroes, | |
1216 | errp); | |
1217 | ||
1218 | case NBD_OPT_INFO: | |
1219 | case NBD_OPT_GO: | |
1220 | ret = nbd_negotiate_handle_info(client, errp); | |
1221 | if (ret == 1) { | |
1222 | assert(option == NBD_OPT_GO); | |
1223 | return 0; | |
1224 | } | |
1225 | break; | |
1226 | ||
1227 | case NBD_OPT_STARTTLS: | |
1228 | if (length) { | |
1229 | ret = nbd_reject_length(client, false, errp); | |
1230 | } else if (client->tlscreds) { | |
1231 | ret = nbd_negotiate_send_rep_err(client, | |
1232 | NBD_REP_ERR_INVALID, errp, | |
1233 | "TLS already enabled"); | |
1234 | } else { | |
1235 | ret = nbd_negotiate_send_rep_err(client, | |
1236 | NBD_REP_ERR_POLICY, errp, | |
1237 | "TLS not configured"); | |
1238 | } | |
1239 | break; | |
1240 | ||
1241 | case NBD_OPT_STRUCTURED_REPLY: | |
1242 | if (length) { | |
1243 | ret = nbd_reject_length(client, false, errp); | |
1244 | } else if (client->structured_reply) { | |
1245 | ret = nbd_negotiate_send_rep_err( | |
1246 | client, NBD_REP_ERR_INVALID, errp, | |
1247 | "structured reply already negotiated"); | |
1248 | } else { | |
1249 | ret = nbd_negotiate_send_rep(client, NBD_REP_ACK, errp); | |
1250 | client->structured_reply = true; | |
1251 | } | |
1252 | break; | |
1253 | ||
1254 | case NBD_OPT_LIST_META_CONTEXT: | |
1255 | case NBD_OPT_SET_META_CONTEXT: | |
1256 | ret = nbd_negotiate_meta_queries(client, &client->export_meta, | |
1257 | errp); | |
1258 | break; | |
1259 | ||
1260 | default: | |
1261 | ret = nbd_opt_drop(client, NBD_REP_ERR_UNSUP, errp, | |
1262 | "Unsupported option %" PRIu32 " (%s)", | |
1263 | option, nbd_opt_lookup(option)); | |
1264 | break; | |
1265 | } | |
1266 | } else { | |
1267 | /* | |
1268 | * If broken new-style we should drop the connection | |
1269 | * for anything except NBD_OPT_EXPORT_NAME | |
1270 | */ | |
1271 | switch (option) { | |
1272 | case NBD_OPT_EXPORT_NAME: | |
1273 | return nbd_negotiate_handle_export_name(client, no_zeroes, | |
1274 | errp); | |
1275 | ||
1276 | default: | |
1277 | error_setg(errp, "Unsupported option %" PRIu32 " (%s)", | |
1278 | option, nbd_opt_lookup(option)); | |
1279 | return -EINVAL; | |
1280 | } | |
1281 | } | |
1282 | if (ret < 0) { | |
1283 | return ret; | |
1284 | } | |
1285 | } | |
1286 | } | |
1287 | ||
1288 | /* nbd_negotiate | |
1289 | * Return: | |
1290 | * -errno on error, errp is set | |
1291 | * 0 on successful negotiation, errp is not set | |
1292 | * 1 if client sent NBD_OPT_ABORT, i.e. on valid disconnect, | |
1293 | * errp is not set | |
1294 | */ | |
1295 | static coroutine_fn int nbd_negotiate(NBDClient *client, Error **errp) | |
1296 | { | |
1297 | ERRP_GUARD(); | |
1298 | char buf[NBD_OLDSTYLE_NEGOTIATE_SIZE] = ""; | |
1299 | int ret; | |
1300 | ||
1301 | /* Old style negotiation header, no room for options | |
1302 | [ 0 .. 7] passwd ("NBDMAGIC") | |
1303 | [ 8 .. 15] magic (NBD_CLIENT_MAGIC) | |
1304 | [16 .. 23] size | |
1305 | [24 .. 27] export flags (zero-extended) | |
1306 | [28 .. 151] reserved (0) | |
1307 | ||
1308 | New style negotiation header, client can send options | |
1309 | [ 0 .. 7] passwd ("NBDMAGIC") | |
1310 | [ 8 .. 15] magic (NBD_OPTS_MAGIC) | |
1311 | [16 .. 17] server flags (0) | |
1312 | ....options sent, ending in NBD_OPT_EXPORT_NAME or NBD_OPT_GO.... | |
1313 | */ | |
1314 | ||
1315 | qio_channel_set_blocking(client->ioc, false, NULL); | |
1316 | ||
1317 | trace_nbd_negotiate_begin(); | |
1318 | memcpy(buf, "NBDMAGIC", 8); | |
1319 | ||
1320 | stq_be_p(buf + 8, NBD_OPTS_MAGIC); | |
1321 | stw_be_p(buf + 16, NBD_FLAG_FIXED_NEWSTYLE | NBD_FLAG_NO_ZEROES); | |
1322 | ||
1323 | if (nbd_write(client->ioc, buf, 18, errp) < 0) { | |
1324 | error_prepend(errp, "write failed: "); | |
1325 | return -EINVAL; | |
1326 | } | |
1327 | ret = nbd_negotiate_options(client, errp); | |
1328 | if (ret != 0) { | |
1329 | if (ret < 0) { | |
1330 | error_prepend(errp, "option negotiation failed: "); | |
1331 | } | |
1332 | return ret; | |
1333 | } | |
1334 | ||
1335 | /* Attach the channel to the same AioContext as the export */ | |
1336 | if (client->exp && client->exp->ctx) { | |
1337 | qio_channel_attach_aio_context(client->ioc, client->exp->ctx); | |
1338 | } | |
1339 | ||
1340 | assert(!client->optlen); | |
1341 | trace_nbd_negotiate_success(); | |
1342 | ||
1343 | return 0; | |
1344 | } | |
1345 | ||
1346 | static int nbd_receive_request(QIOChannel *ioc, NBDRequest *request, | |
1347 | Error **errp) | |
1348 | { | |
1349 | uint8_t buf[NBD_REQUEST_SIZE]; | |
1350 | uint32_t magic; | |
1351 | int ret; | |
1352 | ||
1353 | ret = nbd_read(ioc, buf, sizeof(buf), "request", errp); | |
1354 | if (ret < 0) { | |
1355 | return ret; | |
1356 | } | |
1357 | ||
1358 | /* Request | |
1359 | [ 0 .. 3] magic (NBD_REQUEST_MAGIC) | |
1360 | [ 4 .. 5] flags (NBD_CMD_FLAG_FUA, ...) | |
1361 | [ 6 .. 7] type (NBD_CMD_READ, ...) | |
1362 | [ 8 .. 15] handle | |
1363 | [16 .. 23] from | |
1364 | [24 .. 27] len | |
1365 | */ | |
1366 | ||
1367 | magic = ldl_be_p(buf); | |
1368 | request->flags = lduw_be_p(buf + 4); | |
1369 | request->type = lduw_be_p(buf + 6); | |
1370 | request->handle = ldq_be_p(buf + 8); | |
1371 | request->from = ldq_be_p(buf + 16); | |
1372 | request->len = ldl_be_p(buf + 24); | |
1373 | ||
1374 | trace_nbd_receive_request(magic, request->flags, request->type, | |
1375 | request->from, request->len); | |
1376 | ||
1377 | if (magic != NBD_REQUEST_MAGIC) { | |
1378 | error_setg(errp, "invalid magic (got 0x%" PRIx32 ")", magic); | |
1379 | return -EINVAL; | |
1380 | } | |
1381 | return 0; | |
1382 | } | |
1383 | ||
1384 | #define MAX_NBD_REQUESTS 16 | |
1385 | ||
1386 | void nbd_client_get(NBDClient *client) | |
1387 | { | |
1388 | client->refcount++; | |
1389 | } | |
1390 | ||
1391 | void nbd_client_put(NBDClient *client) | |
1392 | { | |
1393 | if (--client->refcount == 0) { | |
1394 | /* The last reference should be dropped by client->close, | |
1395 | * which is called by client_close. | |
1396 | */ | |
1397 | assert(client->closing); | |
1398 | ||
1399 | qio_channel_detach_aio_context(client->ioc); | |
1400 | object_unref(OBJECT(client->sioc)); | |
1401 | object_unref(OBJECT(client->ioc)); | |
1402 | if (client->tlscreds) { | |
1403 | object_unref(OBJECT(client->tlscreds)); | |
1404 | } | |
1405 | g_free(client->tlsauthz); | |
1406 | if (client->exp) { | |
1407 | QTAILQ_REMOVE(&client->exp->clients, client, next); | |
1408 | nbd_export_put(client->exp); | |
1409 | } | |
1410 | g_free(client); | |
1411 | } | |
1412 | } | |
1413 | ||
1414 | static void client_close(NBDClient *client, bool negotiated) | |
1415 | { | |
1416 | if (client->closing) { | |
1417 | return; | |
1418 | } | |
1419 | ||
1420 | client->closing = true; | |
1421 | ||
1422 | /* Force requests to finish. They will drop their own references, | |
1423 | * then we'll close the socket and free the NBDClient. | |
1424 | */ | |
1425 | qio_channel_shutdown(client->ioc, QIO_CHANNEL_SHUTDOWN_BOTH, | |
1426 | NULL); | |
1427 | ||
1428 | /* Also tell the client, so that they release their reference. */ | |
1429 | if (client->close_fn) { | |
1430 | client->close_fn(client, negotiated); | |
1431 | } | |
1432 | } | |
1433 | ||
1434 | static NBDRequestData *nbd_request_get(NBDClient *client) | |
1435 | { | |
1436 | NBDRequestData *req; | |
1437 | ||
1438 | assert(client->nb_requests <= MAX_NBD_REQUESTS - 1); | |
1439 | client->nb_requests++; | |
1440 | ||
1441 | req = g_new0(NBDRequestData, 1); | |
1442 | nbd_client_get(client); | |
1443 | req->client = client; | |
1444 | return req; | |
1445 | } | |
1446 | ||
1447 | static void nbd_request_put(NBDRequestData *req) | |
1448 | { | |
1449 | NBDClient *client = req->client; | |
1450 | ||
1451 | if (req->data) { | |
1452 | qemu_vfree(req->data); | |
1453 | } | |
1454 | g_free(req); | |
1455 | ||
1456 | client->nb_requests--; | |
1457 | nbd_client_receive_next_request(client); | |
1458 | ||
1459 | nbd_client_put(client); | |
1460 | } | |
1461 | ||
1462 | static void blk_aio_attached(AioContext *ctx, void *opaque) | |
1463 | { | |
1464 | NBDExport *exp = opaque; | |
1465 | NBDClient *client; | |
1466 | ||
1467 | trace_nbd_blk_aio_attached(exp->name, ctx); | |
1468 | ||
1469 | exp->ctx = ctx; | |
1470 | ||
1471 | QTAILQ_FOREACH(client, &exp->clients, next) { | |
1472 | qio_channel_attach_aio_context(client->ioc, ctx); | |
1473 | if (client->recv_coroutine) { | |
1474 | aio_co_schedule(ctx, client->recv_coroutine); | |
1475 | } | |
1476 | if (client->send_coroutine) { | |
1477 | aio_co_schedule(ctx, client->send_coroutine); | |
1478 | } | |
1479 | } | |
1480 | } | |
1481 | ||
1482 | static void blk_aio_detach(void *opaque) | |
1483 | { | |
1484 | NBDExport *exp = opaque; | |
1485 | NBDClient *client; | |
1486 | ||
1487 | trace_nbd_blk_aio_detach(exp->name, exp->ctx); | |
1488 | ||
1489 | QTAILQ_FOREACH(client, &exp->clients, next) { | |
1490 | qio_channel_detach_aio_context(client->ioc); | |
1491 | } | |
1492 | ||
1493 | exp->ctx = NULL; | |
1494 | } | |
1495 | ||
1496 | static void nbd_eject_notifier(Notifier *n, void *data) | |
1497 | { | |
1498 | NBDExport *exp = container_of(n, NBDExport, eject_notifier); | |
1499 | AioContext *aio_context; | |
1500 | ||
1501 | aio_context = exp->ctx; | |
1502 | aio_context_acquire(aio_context); | |
1503 | nbd_export_close(exp); | |
1504 | aio_context_release(aio_context); | |
1505 | } | |
1506 | ||
1507 | NBDExport *nbd_export_new(BlockDriverState *bs, uint64_t dev_offset, | |
1508 | uint64_t size, const char *name, const char *desc, | |
1509 | const char *bitmap, bool readonly, bool shared, | |
1510 | void (*close)(NBDExport *), bool writethrough, | |
1511 | BlockBackend *on_eject_blk, Error **errp) | |
1512 | { | |
1513 | AioContext *ctx; | |
1514 | BlockBackend *blk; | |
1515 | NBDExport *exp = g_new0(NBDExport, 1); | |
1516 | uint64_t perm; | |
1517 | int ret; | |
1518 | ||
1519 | /* | |
1520 | * NBD exports are used for non-shared storage migration. Make sure | |
1521 | * that BDRV_O_INACTIVE is cleared and the image is ready for write | |
1522 | * access since the export could be available before migration handover. | |
1523 | * ctx was acquired in the caller. | |
1524 | */ | |
1525 | assert(name && strlen(name) <= NBD_MAX_STRING_SIZE); | |
1526 | ctx = bdrv_get_aio_context(bs); | |
1527 | bdrv_invalidate_cache(bs, NULL); | |
1528 | ||
1529 | /* Don't allow resize while the NBD server is running, otherwise we don't | |
1530 | * care what happens with the node. */ | |
1531 | perm = BLK_PERM_CONSISTENT_READ; | |
1532 | if (!readonly) { | |
1533 | perm |= BLK_PERM_WRITE; | |
1534 | } | |
1535 | blk = blk_new(ctx, perm, | |
1536 | BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED | | |
1537 | BLK_PERM_WRITE | BLK_PERM_GRAPH_MOD); | |
1538 | ret = blk_insert_bs(blk, bs, errp); | |
1539 | if (ret < 0) { | |
1540 | goto fail; | |
1541 | } | |
1542 | blk_set_enable_write_cache(blk, !writethrough); | |
1543 | blk_set_allow_aio_context_change(blk, true); | |
1544 | ||
1545 | exp->refcount = 1; | |
1546 | QTAILQ_INIT(&exp->clients); | |
1547 | exp->blk = blk; | |
1548 | assert(dev_offset <= INT64_MAX); | |
1549 | exp->dev_offset = dev_offset; | |
1550 | exp->name = g_strdup(name); | |
1551 | assert(!desc || strlen(desc) <= NBD_MAX_STRING_SIZE); | |
1552 | exp->description = g_strdup(desc); | |
1553 | exp->nbdflags = (NBD_FLAG_HAS_FLAGS | NBD_FLAG_SEND_FLUSH | | |
1554 | NBD_FLAG_SEND_FUA | NBD_FLAG_SEND_CACHE); | |
1555 | if (readonly) { | |
1556 | exp->nbdflags |= NBD_FLAG_READ_ONLY; | |
1557 | if (shared) { | |
1558 | exp->nbdflags |= NBD_FLAG_CAN_MULTI_CONN; | |
1559 | } | |
1560 | } else { | |
1561 | exp->nbdflags |= (NBD_FLAG_SEND_TRIM | NBD_FLAG_SEND_WRITE_ZEROES | | |
1562 | NBD_FLAG_SEND_FAST_ZERO); | |
1563 | } | |
1564 | assert(size <= INT64_MAX - dev_offset); | |
1565 | exp->size = QEMU_ALIGN_DOWN(size, BDRV_SECTOR_SIZE); | |
1566 | ||
1567 | if (bitmap) { | |
1568 | BdrvDirtyBitmap *bm = NULL; | |
1569 | ||
1570 | while (bs) { | |
1571 | bm = bdrv_find_dirty_bitmap(bs, bitmap); | |
1572 | if (bm != NULL) { | |
1573 | break; | |
1574 | } | |
1575 | ||
1576 | bs = bdrv_filter_or_cow_bs(bs); | |
1577 | } | |
1578 | ||
1579 | if (bm == NULL) { | |
1580 | error_setg(errp, "Bitmap '%s' is not found", bitmap); | |
1581 | goto fail; | |
1582 | } | |
1583 | ||
1584 | if (bdrv_dirty_bitmap_check(bm, BDRV_BITMAP_ALLOW_RO, errp)) { | |
1585 | goto fail; | |
1586 | } | |
1587 | ||
1588 | if (readonly && bdrv_is_writable(bs) && | |
1589 | bdrv_dirty_bitmap_enabled(bm)) { | |
1590 | error_setg(errp, | |
1591 | "Enabled bitmap '%s' incompatible with readonly export", | |
1592 | bitmap); | |
1593 | goto fail; | |
1594 | } | |
1595 | ||
1596 | bdrv_dirty_bitmap_set_busy(bm, true); | |
1597 | exp->export_bitmap = bm; | |
1598 | assert(strlen(bitmap) <= BDRV_BITMAP_MAX_NAME_SIZE); | |
1599 | exp->export_bitmap_context = g_strdup_printf("qemu:dirty-bitmap:%s", | |
1600 | bitmap); | |
1601 | assert(strlen(exp->export_bitmap_context) < NBD_MAX_STRING_SIZE); | |
1602 | } | |
1603 | ||
1604 | exp->close = close; | |
1605 | exp->ctx = ctx; | |
1606 | blk_add_aio_context_notifier(blk, blk_aio_attached, blk_aio_detach, exp); | |
1607 | ||
1608 | if (on_eject_blk) { | |
1609 | blk_ref(on_eject_blk); | |
1610 | exp->eject_notifier_blk = on_eject_blk; | |
1611 | exp->eject_notifier.notify = nbd_eject_notifier; | |
1612 | blk_add_remove_bs_notifier(on_eject_blk, &exp->eject_notifier); | |
1613 | } | |
1614 | QTAILQ_INSERT_TAIL(&exports, exp, next); | |
1615 | nbd_export_get(exp); | |
1616 | return exp; | |
1617 | ||
1618 | fail: | |
1619 | blk_unref(blk); | |
1620 | g_free(exp->name); | |
1621 | g_free(exp->description); | |
1622 | g_free(exp); | |
1623 | return NULL; | |
1624 | } | |
1625 | ||
1626 | NBDExport *nbd_export_find(const char *name) | |
1627 | { | |
1628 | NBDExport *exp; | |
1629 | QTAILQ_FOREACH(exp, &exports, next) { | |
1630 | if (strcmp(name, exp->name) == 0) { | |
1631 | return exp; | |
1632 | } | |
1633 | } | |
1634 | ||
1635 | return NULL; | |
1636 | } | |
1637 | ||
1638 | AioContext * | |
1639 | nbd_export_aio_context(NBDExport *exp) | |
1640 | { | |
1641 | return exp->ctx; | |
1642 | } | |
1643 | ||
1644 | void nbd_export_close(NBDExport *exp) | |
1645 | { | |
1646 | NBDClient *client, *next; | |
1647 | ||
1648 | nbd_export_get(exp); | |
1649 | /* | |
1650 | * TODO: Should we expand QMP NbdServerRemoveNode enum to allow a | |
1651 | * close mode that stops advertising the export to new clients but | |
1652 | * still permits existing clients to run to completion? Because of | |
1653 | * that possibility, nbd_export_close() can be called more than | |
1654 | * once on an export. | |
1655 | */ | |
1656 | QTAILQ_FOREACH_SAFE(client, &exp->clients, next, next) { | |
1657 | client_close(client, true); | |
1658 | } | |
1659 | if (exp->name) { | |
1660 | nbd_export_put(exp); | |
1661 | g_free(exp->name); | |
1662 | exp->name = NULL; | |
1663 | QTAILQ_REMOVE(&exports, exp, next); | |
1664 | QTAILQ_INSERT_TAIL(&closed_exports, exp, next); | |
1665 | } | |
1666 | g_free(exp->description); | |
1667 | exp->description = NULL; | |
1668 | nbd_export_put(exp); | |
1669 | } | |
1670 | ||
1671 | void nbd_export_remove(NBDExport *exp, NbdServerRemoveMode mode, Error **errp) | |
1672 | { | |
1673 | ERRP_GUARD(); | |
1674 | if (mode == NBD_SERVER_REMOVE_MODE_HARD || QTAILQ_EMPTY(&exp->clients)) { | |
1675 | nbd_export_close(exp); | |
1676 | return; | |
1677 | } | |
1678 | ||
1679 | assert(mode == NBD_SERVER_REMOVE_MODE_SAFE); | |
1680 | ||
1681 | error_setg(errp, "export '%s' still in use", exp->name); | |
1682 | error_append_hint(errp, "Use mode='hard' to force client disconnect\n"); | |
1683 | } | |
1684 | ||
1685 | void nbd_export_get(NBDExport *exp) | |
1686 | { | |
1687 | assert(exp->refcount > 0); | |
1688 | exp->refcount++; | |
1689 | } | |
1690 | ||
1691 | void nbd_export_put(NBDExport *exp) | |
1692 | { | |
1693 | assert(exp->refcount > 0); | |
1694 | if (exp->refcount == 1) { | |
1695 | nbd_export_close(exp); | |
1696 | } | |
1697 | ||
1698 | /* nbd_export_close() may theoretically reduce refcount to 0. It may happen | |
1699 | * if someone calls nbd_export_put() on named export not through | |
1700 | * nbd_export_set_name() when refcount is 1. So, let's assert that | |
1701 | * it is > 0. | |
1702 | */ | |
1703 | assert(exp->refcount > 0); | |
1704 | if (--exp->refcount == 0) { | |
1705 | assert(exp->name == NULL); | |
1706 | assert(exp->description == NULL); | |
1707 | ||
1708 | if (exp->close) { | |
1709 | exp->close(exp); | |
1710 | } | |
1711 | ||
1712 | if (exp->blk) { | |
1713 | if (exp->eject_notifier_blk) { | |
1714 | notifier_remove(&exp->eject_notifier); | |
1715 | blk_unref(exp->eject_notifier_blk); | |
1716 | } | |
1717 | blk_remove_aio_context_notifier(exp->blk, blk_aio_attached, | |
1718 | blk_aio_detach, exp); | |
1719 | blk_unref(exp->blk); | |
1720 | exp->blk = NULL; | |
1721 | } | |
1722 | ||
1723 | if (exp->export_bitmap) { | |
1724 | bdrv_dirty_bitmap_set_busy(exp->export_bitmap, false); | |
1725 | g_free(exp->export_bitmap_context); | |
1726 | } | |
1727 | ||
1728 | QTAILQ_REMOVE(&closed_exports, exp, next); | |
1729 | g_free(exp); | |
1730 | aio_wait_kick(); | |
1731 | } | |
1732 | } | |
1733 | ||
1734 | void nbd_export_close_all(void) | |
1735 | { | |
1736 | NBDExport *exp, *next; | |
1737 | AioContext *aio_context; | |
1738 | ||
1739 | QTAILQ_FOREACH_SAFE(exp, &exports, next, next) { | |
1740 | aio_context = exp->ctx; | |
1741 | aio_context_acquire(aio_context); | |
1742 | nbd_export_close(exp); | |
1743 | aio_context_release(aio_context); | |
1744 | } | |
1745 | ||
1746 | AIO_WAIT_WHILE(NULL, !(QTAILQ_EMPTY(&exports) && | |
1747 | QTAILQ_EMPTY(&closed_exports))); | |
1748 | } | |
1749 | ||
1750 | static int coroutine_fn nbd_co_send_iov(NBDClient *client, struct iovec *iov, | |
1751 | unsigned niov, Error **errp) | |
1752 | { | |
1753 | int ret; | |
1754 | ||
1755 | g_assert(qemu_in_coroutine()); | |
1756 | qemu_co_mutex_lock(&client->send_lock); | |
1757 | client->send_coroutine = qemu_coroutine_self(); | |
1758 | ||
1759 | ret = qio_channel_writev_all(client->ioc, iov, niov, errp) < 0 ? -EIO : 0; | |
1760 | ||
1761 | client->send_coroutine = NULL; | |
1762 | qemu_co_mutex_unlock(&client->send_lock); | |
1763 | ||
1764 | return ret; | |
1765 | } | |
1766 | ||
1767 | static inline void set_be_simple_reply(NBDSimpleReply *reply, uint64_t error, | |
1768 | uint64_t handle) | |
1769 | { | |
1770 | stl_be_p(&reply->magic, NBD_SIMPLE_REPLY_MAGIC); | |
1771 | stl_be_p(&reply->error, error); | |
1772 | stq_be_p(&reply->handle, handle); | |
1773 | } | |
1774 | ||
1775 | static int nbd_co_send_simple_reply(NBDClient *client, | |
1776 | uint64_t handle, | |
1777 | uint32_t error, | |
1778 | void *data, | |
1779 | size_t len, | |
1780 | Error **errp) | |
1781 | { | |
1782 | NBDSimpleReply reply; | |
1783 | int nbd_err = system_errno_to_nbd_errno(error); | |
1784 | struct iovec iov[] = { | |
1785 | {.iov_base = &reply, .iov_len = sizeof(reply)}, | |
1786 | {.iov_base = data, .iov_len = len} | |
1787 | }; | |
1788 | ||
1789 | trace_nbd_co_send_simple_reply(handle, nbd_err, nbd_err_lookup(nbd_err), | |
1790 | len); | |
1791 | set_be_simple_reply(&reply, nbd_err, handle); | |
1792 | ||
1793 | return nbd_co_send_iov(client, iov, len ? 2 : 1, errp); | |
1794 | } | |
1795 | ||
1796 | static inline void set_be_chunk(NBDStructuredReplyChunk *chunk, uint16_t flags, | |
1797 | uint16_t type, uint64_t handle, uint32_t length) | |
1798 | { | |
1799 | stl_be_p(&chunk->magic, NBD_STRUCTURED_REPLY_MAGIC); | |
1800 | stw_be_p(&chunk->flags, flags); | |
1801 | stw_be_p(&chunk->type, type); | |
1802 | stq_be_p(&chunk->handle, handle); | |
1803 | stl_be_p(&chunk->length, length); | |
1804 | } | |
1805 | ||
1806 | static int coroutine_fn nbd_co_send_structured_done(NBDClient *client, | |
1807 | uint64_t handle, | |
1808 | Error **errp) | |
1809 | { | |
1810 | NBDStructuredReplyChunk chunk; | |
1811 | struct iovec iov[] = { | |
1812 | {.iov_base = &chunk, .iov_len = sizeof(chunk)}, | |
1813 | }; | |
1814 | ||
1815 | trace_nbd_co_send_structured_done(handle); | |
1816 | set_be_chunk(&chunk, NBD_REPLY_FLAG_DONE, NBD_REPLY_TYPE_NONE, handle, 0); | |
1817 | ||
1818 | return nbd_co_send_iov(client, iov, 1, errp); | |
1819 | } | |
1820 | ||
1821 | static int coroutine_fn nbd_co_send_structured_read(NBDClient *client, | |
1822 | uint64_t handle, | |
1823 | uint64_t offset, | |
1824 | void *data, | |
1825 | size_t size, | |
1826 | bool final, | |
1827 | Error **errp) | |
1828 | { | |
1829 | NBDStructuredReadData chunk; | |
1830 | struct iovec iov[] = { | |
1831 | {.iov_base = &chunk, .iov_len = sizeof(chunk)}, | |
1832 | {.iov_base = data, .iov_len = size} | |
1833 | }; | |
1834 | ||
1835 | assert(size); | |
1836 | trace_nbd_co_send_structured_read(handle, offset, data, size); | |
1837 | set_be_chunk(&chunk.h, final ? NBD_REPLY_FLAG_DONE : 0, | |
1838 | NBD_REPLY_TYPE_OFFSET_DATA, handle, | |
1839 | sizeof(chunk) - sizeof(chunk.h) + size); | |
1840 | stq_be_p(&chunk.offset, offset); | |
1841 | ||
1842 | return nbd_co_send_iov(client, iov, 2, errp); | |
1843 | } | |
1844 | ||
1845 | static int coroutine_fn nbd_co_send_structured_error(NBDClient *client, | |
1846 | uint64_t handle, | |
1847 | uint32_t error, | |
1848 | const char *msg, | |
1849 | Error **errp) | |
1850 | { | |
1851 | NBDStructuredError chunk; | |
1852 | int nbd_err = system_errno_to_nbd_errno(error); | |
1853 | struct iovec iov[] = { | |
1854 | {.iov_base = &chunk, .iov_len = sizeof(chunk)}, | |
1855 | {.iov_base = (char *)msg, .iov_len = msg ? strlen(msg) : 0}, | |
1856 | }; | |
1857 | ||
1858 | assert(nbd_err); | |
1859 | trace_nbd_co_send_structured_error(handle, nbd_err, | |
1860 | nbd_err_lookup(nbd_err), msg ? msg : ""); | |
1861 | set_be_chunk(&chunk.h, NBD_REPLY_FLAG_DONE, NBD_REPLY_TYPE_ERROR, handle, | |
1862 | sizeof(chunk) - sizeof(chunk.h) + iov[1].iov_len); | |
1863 | stl_be_p(&chunk.error, nbd_err); | |
1864 | stw_be_p(&chunk.message_length, iov[1].iov_len); | |
1865 | ||
1866 | return nbd_co_send_iov(client, iov, 1 + !!iov[1].iov_len, errp); | |
1867 | } | |
1868 | ||
1869 | /* Do a sparse read and send the structured reply to the client. | |
1870 | * Returns -errno if sending fails. bdrv_block_status_above() failure is | |
1871 | * reported to the client, at which point this function succeeds. | |
1872 | */ | |
1873 | static int coroutine_fn nbd_co_send_sparse_read(NBDClient *client, | |
1874 | uint64_t handle, | |
1875 | uint64_t offset, | |
1876 | uint8_t *data, | |
1877 | size_t size, | |
1878 | Error **errp) | |
1879 | { | |
1880 | int ret = 0; | |
1881 | NBDExport *exp = client->exp; | |
1882 | size_t progress = 0; | |
1883 | ||
1884 | while (progress < size) { | |
1885 | int64_t pnum; | |
1886 | int status = bdrv_block_status_above(blk_bs(exp->blk), NULL, | |
1887 | offset + progress, | |
1888 | size - progress, &pnum, NULL, | |
1889 | NULL); | |
1890 | bool final; | |
1891 | ||
1892 | if (status < 0) { | |
1893 | char *msg = g_strdup_printf("unable to check for holes: %s", | |
1894 | strerror(-status)); | |
1895 | ||
1896 | ret = nbd_co_send_structured_error(client, handle, -status, msg, | |
1897 | errp); | |
1898 | g_free(msg); | |
1899 | return ret; | |
1900 | } | |
1901 | assert(pnum && pnum <= size - progress); | |
1902 | final = progress + pnum == size; | |
1903 | if (status & BDRV_BLOCK_ZERO) { | |
1904 | NBDStructuredReadHole chunk; | |
1905 | struct iovec iov[] = { | |
1906 | {.iov_base = &chunk, .iov_len = sizeof(chunk)}, | |
1907 | }; | |
1908 | ||
1909 | trace_nbd_co_send_structured_read_hole(handle, offset + progress, | |
1910 | pnum); | |
1911 | set_be_chunk(&chunk.h, final ? NBD_REPLY_FLAG_DONE : 0, | |
1912 | NBD_REPLY_TYPE_OFFSET_HOLE, | |
1913 | handle, sizeof(chunk) - sizeof(chunk.h)); | |
1914 | stq_be_p(&chunk.offset, offset + progress); | |
1915 | stl_be_p(&chunk.length, pnum); | |
1916 | ret = nbd_co_send_iov(client, iov, 1, errp); | |
1917 | } else { | |
1918 | ret = blk_pread(exp->blk, offset + progress + exp->dev_offset, | |
1919 | data + progress, pnum); | |
1920 | if (ret < 0) { | |
1921 | error_setg_errno(errp, -ret, "reading from file failed"); | |
1922 | break; | |
1923 | } | |
1924 | ret = nbd_co_send_structured_read(client, handle, offset + progress, | |
1925 | data + progress, pnum, final, | |
1926 | errp); | |
1927 | } | |
1928 | ||
1929 | if (ret < 0) { | |
1930 | break; | |
1931 | } | |
1932 | progress += pnum; | |
1933 | } | |
1934 | return ret; | |
1935 | } | |
1936 | ||
1937 | typedef struct NBDExtentArray { | |
1938 | NBDExtent *extents; | |
1939 | unsigned int nb_alloc; | |
1940 | unsigned int count; | |
1941 | uint64_t total_length; | |
1942 | bool can_add; | |
1943 | bool converted_to_be; | |
1944 | } NBDExtentArray; | |
1945 | ||
1946 | static NBDExtentArray *nbd_extent_array_new(unsigned int nb_alloc) | |
1947 | { | |
1948 | NBDExtentArray *ea = g_new0(NBDExtentArray, 1); | |
1949 | ||
1950 | ea->nb_alloc = nb_alloc; | |
1951 | ea->extents = g_new(NBDExtent, nb_alloc); | |
1952 | ea->can_add = true; | |
1953 | ||
1954 | return ea; | |
1955 | } | |
1956 | ||
1957 | static void nbd_extent_array_free(NBDExtentArray *ea) | |
1958 | { | |
1959 | g_free(ea->extents); | |
1960 | g_free(ea); | |
1961 | } | |
1962 | G_DEFINE_AUTOPTR_CLEANUP_FUNC(NBDExtentArray, nbd_extent_array_free); | |
1963 | ||
1964 | /* Further modifications of the array after conversion are abandoned */ | |
1965 | static void nbd_extent_array_convert_to_be(NBDExtentArray *ea) | |
1966 | { | |
1967 | int i; | |
1968 | ||
1969 | assert(!ea->converted_to_be); | |
1970 | ea->can_add = false; | |
1971 | ea->converted_to_be = true; | |
1972 | ||
1973 | for (i = 0; i < ea->count; i++) { | |
1974 | ea->extents[i].flags = cpu_to_be32(ea->extents[i].flags); | |
1975 | ea->extents[i].length = cpu_to_be32(ea->extents[i].length); | |
1976 | } | |
1977 | } | |
1978 | ||
1979 | /* | |
1980 | * Add extent to NBDExtentArray. If extent can't be added (no available space), | |
1981 | * return -1. | |
1982 | * For safety, when returning -1 for the first time, .can_add is set to false, | |
1983 | * further call to nbd_extent_array_add() will crash. | |
1984 | * (to avoid the situation, when after failing to add an extent (returned -1), | |
1985 | * user miss this failure and add another extent, which is successfully added | |
1986 | * (array is full, but new extent may be squashed into the last one), then we | |
1987 | * have invalid array with skipped extent) | |
1988 | */ | |
1989 | static int nbd_extent_array_add(NBDExtentArray *ea, | |
1990 | uint32_t length, uint32_t flags) | |
1991 | { | |
1992 | assert(ea->can_add); | |
1993 | ||
1994 | if (!length) { | |
1995 | return 0; | |
1996 | } | |
1997 | ||
1998 | /* Extend previous extent if flags are the same */ | |
1999 | if (ea->count > 0 && flags == ea->extents[ea->count - 1].flags) { | |
2000 | uint64_t sum = (uint64_t)length + ea->extents[ea->count - 1].length; | |
2001 | ||
2002 | if (sum <= UINT32_MAX) { | |
2003 | ea->extents[ea->count - 1].length = sum; | |
2004 | ea->total_length += length; | |
2005 | return 0; | |
2006 | } | |
2007 | } | |
2008 | ||
2009 | if (ea->count >= ea->nb_alloc) { | |
2010 | ea->can_add = false; | |
2011 | return -1; | |
2012 | } | |
2013 | ||
2014 | ea->total_length += length; | |
2015 | ea->extents[ea->count] = (NBDExtent) {.length = length, .flags = flags}; | |
2016 | ea->count++; | |
2017 | ||
2018 | return 0; | |
2019 | } | |
2020 | ||
2021 | static int blockstatus_to_extents(BlockDriverState *bs, uint64_t offset, | |
2022 | uint64_t bytes, NBDExtentArray *ea) | |
2023 | { | |
2024 | while (bytes) { | |
2025 | uint32_t flags; | |
2026 | int64_t num; | |
2027 | int ret = bdrv_block_status_above(bs, NULL, offset, bytes, &num, | |
2028 | NULL, NULL); | |
2029 | ||
2030 | if (ret < 0) { | |
2031 | return ret; | |
2032 | } | |
2033 | ||
2034 | flags = (ret & BDRV_BLOCK_ALLOCATED ? 0 : NBD_STATE_HOLE) | | |
2035 | (ret & BDRV_BLOCK_ZERO ? NBD_STATE_ZERO : 0); | |
2036 | ||
2037 | if (nbd_extent_array_add(ea, num, flags) < 0) { | |
2038 | return 0; | |
2039 | } | |
2040 | ||
2041 | offset += num; | |
2042 | bytes -= num; | |
2043 | } | |
2044 | ||
2045 | return 0; | |
2046 | } | |
2047 | ||
2048 | /* | |
2049 | * nbd_co_send_extents | |
2050 | * | |
2051 | * @ea is converted to BE by the function | |
2052 | * @last controls whether NBD_REPLY_FLAG_DONE is sent. | |
2053 | */ | |
2054 | static int nbd_co_send_extents(NBDClient *client, uint64_t handle, | |
2055 | NBDExtentArray *ea, | |
2056 | bool last, uint32_t context_id, Error **errp) | |
2057 | { | |
2058 | NBDStructuredMeta chunk; | |
2059 | struct iovec iov[] = { | |
2060 | {.iov_base = &chunk, .iov_len = sizeof(chunk)}, | |
2061 | {.iov_base = ea->extents, .iov_len = ea->count * sizeof(ea->extents[0])} | |
2062 | }; | |
2063 | ||
2064 | nbd_extent_array_convert_to_be(ea); | |
2065 | ||
2066 | trace_nbd_co_send_extents(handle, ea->count, context_id, ea->total_length, | |
2067 | last); | |
2068 | set_be_chunk(&chunk.h, last ? NBD_REPLY_FLAG_DONE : 0, | |
2069 | NBD_REPLY_TYPE_BLOCK_STATUS, | |
2070 | handle, sizeof(chunk) - sizeof(chunk.h) + iov[1].iov_len); | |
2071 | stl_be_p(&chunk.context_id, context_id); | |
2072 | ||
2073 | return nbd_co_send_iov(client, iov, 2, errp); | |
2074 | } | |
2075 | ||
2076 | /* Get block status from the exported device and send it to the client */ | |
2077 | static int nbd_co_send_block_status(NBDClient *client, uint64_t handle, | |
2078 | BlockDriverState *bs, uint64_t offset, | |
2079 | uint32_t length, bool dont_fragment, | |
2080 | bool last, uint32_t context_id, | |
2081 | Error **errp) | |
2082 | { | |
2083 | int ret; | |
2084 | unsigned int nb_extents = dont_fragment ? 1 : NBD_MAX_BLOCK_STATUS_EXTENTS; | |
2085 | g_autoptr(NBDExtentArray) ea = nbd_extent_array_new(nb_extents); | |
2086 | ||
2087 | ret = blockstatus_to_extents(bs, offset, length, ea); | |
2088 | if (ret < 0) { | |
2089 | return nbd_co_send_structured_error( | |
2090 | client, handle, -ret, "can't get block status", errp); | |
2091 | } | |
2092 | ||
2093 | return nbd_co_send_extents(client, handle, ea, last, context_id, errp); | |
2094 | } | |
2095 | ||
2096 | /* Populate @ea from a dirty bitmap. */ | |
2097 | static void bitmap_to_extents(BdrvDirtyBitmap *bitmap, | |
2098 | uint64_t offset, uint64_t length, | |
2099 | NBDExtentArray *es) | |
2100 | { | |
2101 | int64_t start, dirty_start, dirty_count; | |
2102 | int64_t end = offset + length; | |
2103 | bool full = false; | |
2104 | ||
2105 | bdrv_dirty_bitmap_lock(bitmap); | |
2106 | ||
2107 | for (start = offset; | |
2108 | bdrv_dirty_bitmap_next_dirty_area(bitmap, start, end, INT32_MAX, | |
2109 | &dirty_start, &dirty_count); | |
2110 | start = dirty_start + dirty_count) | |
2111 | { | |
2112 | if ((nbd_extent_array_add(es, dirty_start - start, 0) < 0) || | |
2113 | (nbd_extent_array_add(es, dirty_count, NBD_STATE_DIRTY) < 0)) | |
2114 | { | |
2115 | full = true; | |
2116 | break; | |
2117 | } | |
2118 | } | |
2119 | ||
2120 | if (!full) { | |
2121 | /* last non dirty extent */ | |
2122 | nbd_extent_array_add(es, end - start, 0); | |
2123 | } | |
2124 | ||
2125 | bdrv_dirty_bitmap_unlock(bitmap); | |
2126 | } | |
2127 | ||
2128 | static int nbd_co_send_bitmap(NBDClient *client, uint64_t handle, | |
2129 | BdrvDirtyBitmap *bitmap, uint64_t offset, | |
2130 | uint32_t length, bool dont_fragment, bool last, | |
2131 | uint32_t context_id, Error **errp) | |
2132 | { | |
2133 | unsigned int nb_extents = dont_fragment ? 1 : NBD_MAX_BLOCK_STATUS_EXTENTS; | |
2134 | g_autoptr(NBDExtentArray) ea = nbd_extent_array_new(nb_extents); | |
2135 | ||
2136 | bitmap_to_extents(bitmap, offset, length, ea); | |
2137 | ||
2138 | return nbd_co_send_extents(client, handle, ea, last, context_id, errp); | |
2139 | } | |
2140 | ||
2141 | /* nbd_co_receive_request | |
2142 | * Collect a client request. Return 0 if request looks valid, -EIO to drop | |
2143 | * connection right away, and any other negative value to report an error to | |
2144 | * the client (although the caller may still need to disconnect after reporting | |
2145 | * the error). | |
2146 | */ | |
2147 | static int nbd_co_receive_request(NBDRequestData *req, NBDRequest *request, | |
2148 | Error **errp) | |
2149 | { | |
2150 | NBDClient *client = req->client; | |
2151 | int valid_flags; | |
2152 | ||
2153 | g_assert(qemu_in_coroutine()); | |
2154 | assert(client->recv_coroutine == qemu_coroutine_self()); | |
2155 | if (nbd_receive_request(client->ioc, request, errp) < 0) { | |
2156 | return -EIO; | |
2157 | } | |
2158 | ||
2159 | trace_nbd_co_receive_request_decode_type(request->handle, request->type, | |
2160 | nbd_cmd_lookup(request->type)); | |
2161 | ||
2162 | if (request->type != NBD_CMD_WRITE) { | |
2163 | /* No payload, we are ready to read the next request. */ | |
2164 | req->complete = true; | |
2165 | } | |
2166 | ||
2167 | if (request->type == NBD_CMD_DISC) { | |
2168 | /* Special case: we're going to disconnect without a reply, | |
2169 | * whether or not flags, from, or len are bogus */ | |
2170 | return -EIO; | |
2171 | } | |
2172 | ||
2173 | if (request->type == NBD_CMD_READ || request->type == NBD_CMD_WRITE || | |
2174 | request->type == NBD_CMD_CACHE) | |
2175 | { | |
2176 | if (request->len > NBD_MAX_BUFFER_SIZE) { | |
2177 | error_setg(errp, "len (%" PRIu32" ) is larger than max len (%u)", | |
2178 | request->len, NBD_MAX_BUFFER_SIZE); | |
2179 | return -EINVAL; | |
2180 | } | |
2181 | ||
2182 | if (request->type != NBD_CMD_CACHE) { | |
2183 | req->data = blk_try_blockalign(client->exp->blk, request->len); | |
2184 | if (req->data == NULL) { | |
2185 | error_setg(errp, "No memory"); | |
2186 | return -ENOMEM; | |
2187 | } | |
2188 | } | |
2189 | } | |
2190 | ||
2191 | if (request->type == NBD_CMD_WRITE) { | |
2192 | if (nbd_read(client->ioc, req->data, request->len, "CMD_WRITE data", | |
2193 | errp) < 0) | |
2194 | { | |
2195 | return -EIO; | |
2196 | } | |
2197 | req->complete = true; | |
2198 | ||
2199 | trace_nbd_co_receive_request_payload_received(request->handle, | |
2200 | request->len); | |
2201 | } | |
2202 | ||
2203 | /* Sanity checks. */ | |
2204 | if (client->exp->nbdflags & NBD_FLAG_READ_ONLY && | |
2205 | (request->type == NBD_CMD_WRITE || | |
2206 | request->type == NBD_CMD_WRITE_ZEROES || | |
2207 | request->type == NBD_CMD_TRIM)) { | |
2208 | error_setg(errp, "Export is read-only"); | |
2209 | return -EROFS; | |
2210 | } | |
2211 | if (request->from > client->exp->size || | |
2212 | request->len > client->exp->size - request->from) { | |
2213 | error_setg(errp, "operation past EOF; From: %" PRIu64 ", Len: %" PRIu32 | |
2214 | ", Size: %" PRIu64, request->from, request->len, | |
2215 | client->exp->size); | |
2216 | return (request->type == NBD_CMD_WRITE || | |
2217 | request->type == NBD_CMD_WRITE_ZEROES) ? -ENOSPC : -EINVAL; | |
2218 | } | |
2219 | if (client->check_align && !QEMU_IS_ALIGNED(request->from | request->len, | |
2220 | client->check_align)) { | |
2221 | /* | |
2222 | * The block layer gracefully handles unaligned requests, but | |
2223 | * it's still worth tracing client non-compliance | |
2224 | */ | |
2225 | trace_nbd_co_receive_align_compliance(nbd_cmd_lookup(request->type), | |
2226 | request->from, | |
2227 | request->len, | |
2228 | client->check_align); | |
2229 | } | |
2230 | valid_flags = NBD_CMD_FLAG_FUA; | |
2231 | if (request->type == NBD_CMD_READ && client->structured_reply) { | |
2232 | valid_flags |= NBD_CMD_FLAG_DF; | |
2233 | } else if (request->type == NBD_CMD_WRITE_ZEROES) { | |
2234 | valid_flags |= NBD_CMD_FLAG_NO_HOLE | NBD_CMD_FLAG_FAST_ZERO; | |
2235 | } else if (request->type == NBD_CMD_BLOCK_STATUS) { | |
2236 | valid_flags |= NBD_CMD_FLAG_REQ_ONE; | |
2237 | } | |
2238 | if (request->flags & ~valid_flags) { | |
2239 | error_setg(errp, "unsupported flags for command %s (got 0x%x)", | |
2240 | nbd_cmd_lookup(request->type), request->flags); | |
2241 | return -EINVAL; | |
2242 | } | |
2243 | ||
2244 | return 0; | |
2245 | } | |
2246 | ||
2247 | /* Send simple reply without a payload, or a structured error | |
2248 | * @error_msg is ignored if @ret >= 0 | |
2249 | * Returns 0 if connection is still live, -errno on failure to talk to client | |
2250 | */ | |
2251 | static coroutine_fn int nbd_send_generic_reply(NBDClient *client, | |
2252 | uint64_t handle, | |
2253 | int ret, | |
2254 | const char *error_msg, | |
2255 | Error **errp) | |
2256 | { | |
2257 | if (client->structured_reply && ret < 0) { | |
2258 | return nbd_co_send_structured_error(client, handle, -ret, error_msg, | |
2259 | errp); | |
2260 | } else { | |
2261 | return nbd_co_send_simple_reply(client, handle, ret < 0 ? -ret : 0, | |
2262 | NULL, 0, errp); | |
2263 | } | |
2264 | } | |
2265 | ||
2266 | /* Handle NBD_CMD_READ request. | |
2267 | * Return -errno if sending fails. Other errors are reported directly to the | |
2268 | * client as an error reply. */ | |
2269 | static coroutine_fn int nbd_do_cmd_read(NBDClient *client, NBDRequest *request, | |
2270 | uint8_t *data, Error **errp) | |
2271 | { | |
2272 | int ret; | |
2273 | NBDExport *exp = client->exp; | |
2274 | ||
2275 | assert(request->type == NBD_CMD_READ); | |
2276 | ||
2277 | /* XXX: NBD Protocol only documents use of FUA with WRITE */ | |
2278 | if (request->flags & NBD_CMD_FLAG_FUA) { | |
2279 | ret = blk_co_flush(exp->blk); | |
2280 | if (ret < 0) { | |
2281 | return nbd_send_generic_reply(client, request->handle, ret, | |
2282 | "flush failed", errp); | |
2283 | } | |
2284 | } | |
2285 | ||
2286 | if (client->structured_reply && !(request->flags & NBD_CMD_FLAG_DF) && | |
2287 | request->len) | |
2288 | { | |
2289 | return nbd_co_send_sparse_read(client, request->handle, request->from, | |
2290 | data, request->len, errp); | |
2291 | } | |
2292 | ||
2293 | ret = blk_pread(exp->blk, request->from + exp->dev_offset, data, | |
2294 | request->len); | |
2295 | if (ret < 0) { | |
2296 | return nbd_send_generic_reply(client, request->handle, ret, | |
2297 | "reading from file failed", errp); | |
2298 | } | |
2299 | ||
2300 | if (client->structured_reply) { | |
2301 | if (request->len) { | |
2302 | return nbd_co_send_structured_read(client, request->handle, | |
2303 | request->from, data, | |
2304 | request->len, true, errp); | |
2305 | } else { | |
2306 | return nbd_co_send_structured_done(client, request->handle, errp); | |
2307 | } | |
2308 | } else { | |
2309 | return nbd_co_send_simple_reply(client, request->handle, 0, | |
2310 | data, request->len, errp); | |
2311 | } | |
2312 | } | |
2313 | ||
2314 | /* | |
2315 | * nbd_do_cmd_cache | |
2316 | * | |
2317 | * Handle NBD_CMD_CACHE request. | |
2318 | * Return -errno if sending fails. Other errors are reported directly to the | |
2319 | * client as an error reply. | |
2320 | */ | |
2321 | static coroutine_fn int nbd_do_cmd_cache(NBDClient *client, NBDRequest *request, | |
2322 | Error **errp) | |
2323 | { | |
2324 | int ret; | |
2325 | NBDExport *exp = client->exp; | |
2326 | ||
2327 | assert(request->type == NBD_CMD_CACHE); | |
2328 | ||
2329 | ret = blk_co_preadv(exp->blk, request->from + exp->dev_offset, request->len, | |
2330 | NULL, BDRV_REQ_COPY_ON_READ | BDRV_REQ_PREFETCH); | |
2331 | ||
2332 | return nbd_send_generic_reply(client, request->handle, ret, | |
2333 | "caching data failed", errp); | |
2334 | } | |
2335 | ||
2336 | /* Handle NBD request. | |
2337 | * Return -errno if sending fails. Other errors are reported directly to the | |
2338 | * client as an error reply. */ | |
2339 | static coroutine_fn int nbd_handle_request(NBDClient *client, | |
2340 | NBDRequest *request, | |
2341 | uint8_t *data, Error **errp) | |
2342 | { | |
2343 | int ret; | |
2344 | int flags; | |
2345 | NBDExport *exp = client->exp; | |
2346 | char *msg; | |
2347 | ||
2348 | switch (request->type) { | |
2349 | case NBD_CMD_CACHE: | |
2350 | return nbd_do_cmd_cache(client, request, errp); | |
2351 | ||
2352 | case NBD_CMD_READ: | |
2353 | return nbd_do_cmd_read(client, request, data, errp); | |
2354 | ||
2355 | case NBD_CMD_WRITE: | |
2356 | flags = 0; | |
2357 | if (request->flags & NBD_CMD_FLAG_FUA) { | |
2358 | flags |= BDRV_REQ_FUA; | |
2359 | } | |
2360 | ret = blk_pwrite(exp->blk, request->from + exp->dev_offset, | |
2361 | data, request->len, flags); | |
2362 | return nbd_send_generic_reply(client, request->handle, ret, | |
2363 | "writing to file failed", errp); | |
2364 | ||
2365 | case NBD_CMD_WRITE_ZEROES: | |
2366 | flags = 0; | |
2367 | if (request->flags & NBD_CMD_FLAG_FUA) { | |
2368 | flags |= BDRV_REQ_FUA; | |
2369 | } | |
2370 | if (!(request->flags & NBD_CMD_FLAG_NO_HOLE)) { | |
2371 | flags |= BDRV_REQ_MAY_UNMAP; | |
2372 | } | |
2373 | if (request->flags & NBD_CMD_FLAG_FAST_ZERO) { | |
2374 | flags |= BDRV_REQ_NO_FALLBACK; | |
2375 | } | |
2376 | ret = 0; | |
2377 | /* FIXME simplify this when blk_pwrite_zeroes switches to 64-bit */ | |
2378 | while (ret >= 0 && request->len) { | |
2379 | int align = client->check_align ?: 1; | |
2380 | int len = MIN(request->len, QEMU_ALIGN_DOWN(BDRV_REQUEST_MAX_BYTES, | |
2381 | align)); | |
2382 | ret = blk_pwrite_zeroes(exp->blk, request->from + exp->dev_offset, | |
2383 | len, flags); | |
2384 | request->len -= len; | |
2385 | request->from += len; | |
2386 | } | |
2387 | return nbd_send_generic_reply(client, request->handle, ret, | |
2388 | "writing to file failed", errp); | |
2389 | ||
2390 | case NBD_CMD_DISC: | |
2391 | /* unreachable, thanks to special case in nbd_co_receive_request() */ | |
2392 | abort(); | |
2393 | ||
2394 | case NBD_CMD_FLUSH: | |
2395 | ret = blk_co_flush(exp->blk); | |
2396 | return nbd_send_generic_reply(client, request->handle, ret, | |
2397 | "flush failed", errp); | |
2398 | ||
2399 | case NBD_CMD_TRIM: | |
2400 | ret = 0; | |
2401 | /* FIXME simplify this when blk_co_pdiscard switches to 64-bit */ | |
2402 | while (ret >= 0 && request->len) { | |
2403 | int align = client->check_align ?: 1; | |
2404 | int len = MIN(request->len, QEMU_ALIGN_DOWN(BDRV_REQUEST_MAX_BYTES, | |
2405 | align)); | |
2406 | ret = blk_co_pdiscard(exp->blk, request->from + exp->dev_offset, | |
2407 | len); | |
2408 | request->len -= len; | |
2409 | request->from += len; | |
2410 | } | |
2411 | if (ret >= 0 && request->flags & NBD_CMD_FLAG_FUA) { | |
2412 | ret = blk_co_flush(exp->blk); | |
2413 | } | |
2414 | return nbd_send_generic_reply(client, request->handle, ret, | |
2415 | "discard failed", errp); | |
2416 | ||
2417 | case NBD_CMD_BLOCK_STATUS: | |
2418 | if (!request->len) { | |
2419 | return nbd_send_generic_reply(client, request->handle, -EINVAL, | |
2420 | "need non-zero length", errp); | |
2421 | } | |
2422 | if (client->export_meta.valid && | |
2423 | (client->export_meta.base_allocation || | |
2424 | client->export_meta.bitmap)) | |
2425 | { | |
2426 | bool dont_fragment = request->flags & NBD_CMD_FLAG_REQ_ONE; | |
2427 | ||
2428 | if (client->export_meta.base_allocation) { | |
2429 | ret = nbd_co_send_block_status(client, request->handle, | |
2430 | blk_bs(exp->blk), request->from, | |
2431 | request->len, dont_fragment, | |
2432 | !client->export_meta.bitmap, | |
2433 | NBD_META_ID_BASE_ALLOCATION, | |
2434 | errp); | |
2435 | if (ret < 0) { | |
2436 | return ret; | |
2437 | } | |
2438 | } | |
2439 | ||
2440 | if (client->export_meta.bitmap) { | |
2441 | ret = nbd_co_send_bitmap(client, request->handle, | |
2442 | client->exp->export_bitmap, | |
2443 | request->from, request->len, | |
2444 | dont_fragment, | |
2445 | true, NBD_META_ID_DIRTY_BITMAP, errp); | |
2446 | if (ret < 0) { | |
2447 | return ret; | |
2448 | } | |
2449 | } | |
2450 | ||
2451 | return 0; | |
2452 | } else { | |
2453 | return nbd_send_generic_reply(client, request->handle, -EINVAL, | |
2454 | "CMD_BLOCK_STATUS not negotiated", | |
2455 | errp); | |
2456 | } | |
2457 | ||
2458 | default: | |
2459 | msg = g_strdup_printf("invalid request type (%" PRIu32 ") received", | |
2460 | request->type); | |
2461 | ret = nbd_send_generic_reply(client, request->handle, -EINVAL, msg, | |
2462 | errp); | |
2463 | g_free(msg); | |
2464 | return ret; | |
2465 | } | |
2466 | } | |
2467 | ||
2468 | /* Owns a reference to the NBDClient passed as opaque. */ | |
2469 | static coroutine_fn void nbd_trip(void *opaque) | |
2470 | { | |
2471 | NBDClient *client = opaque; | |
2472 | NBDRequestData *req; | |
2473 | NBDRequest request = { 0 }; /* GCC thinks it can be used uninitialized */ | |
2474 | int ret; | |
2475 | Error *local_err = NULL; | |
2476 | ||
2477 | trace_nbd_trip(); | |
2478 | if (client->closing) { | |
2479 | nbd_client_put(client); | |
2480 | return; | |
2481 | } | |
2482 | ||
2483 | req = nbd_request_get(client); | |
2484 | ret = nbd_co_receive_request(req, &request, &local_err); | |
2485 | client->recv_coroutine = NULL; | |
2486 | ||
2487 | if (client->closing) { | |
2488 | /* | |
2489 | * The client may be closed when we are blocked in | |
2490 | * nbd_co_receive_request() | |
2491 | */ | |
2492 | goto done; | |
2493 | } | |
2494 | ||
2495 | nbd_client_receive_next_request(client); | |
2496 | if (ret == -EIO) { | |
2497 | goto disconnect; | |
2498 | } | |
2499 | ||
2500 | if (ret < 0) { | |
2501 | /* It wans't -EIO, so, according to nbd_co_receive_request() | |
2502 | * semantics, we should return the error to the client. */ | |
2503 | Error *export_err = local_err; | |
2504 | ||
2505 | local_err = NULL; | |
2506 | ret = nbd_send_generic_reply(client, request.handle, -EINVAL, | |
2507 | error_get_pretty(export_err), &local_err); | |
2508 | error_free(export_err); | |
2509 | } else { | |
2510 | ret = nbd_handle_request(client, &request, req->data, &local_err); | |
2511 | } | |
2512 | if (ret < 0) { | |
2513 | error_prepend(&local_err, "Failed to send reply: "); | |
2514 | goto disconnect; | |
2515 | } | |
2516 | ||
2517 | /* We must disconnect after NBD_CMD_WRITE if we did not | |
2518 | * read the payload. | |
2519 | */ | |
2520 | if (!req->complete) { | |
2521 | error_setg(&local_err, "Request handling failed in intermediate state"); | |
2522 | goto disconnect; | |
2523 | } | |
2524 | ||
2525 | done: | |
2526 | nbd_request_put(req); | |
2527 | nbd_client_put(client); | |
2528 | return; | |
2529 | ||
2530 | disconnect: | |
2531 | if (local_err) { | |
2532 | error_reportf_err(local_err, "Disconnect client, due to: "); | |
2533 | } | |
2534 | nbd_request_put(req); | |
2535 | client_close(client, true); | |
2536 | nbd_client_put(client); | |
2537 | } | |
2538 | ||
2539 | static void nbd_client_receive_next_request(NBDClient *client) | |
2540 | { | |
2541 | if (!client->recv_coroutine && client->nb_requests < MAX_NBD_REQUESTS) { | |
2542 | nbd_client_get(client); | |
2543 | client->recv_coroutine = qemu_coroutine_create(nbd_trip, client); | |
2544 | aio_co_schedule(client->exp->ctx, client->recv_coroutine); | |
2545 | } | |
2546 | } | |
2547 | ||
2548 | static coroutine_fn void nbd_co_client_start(void *opaque) | |
2549 | { | |
2550 | NBDClient *client = opaque; | |
2551 | Error *local_err = NULL; | |
2552 | ||
2553 | qemu_co_mutex_init(&client->send_lock); | |
2554 | ||
2555 | if (nbd_negotiate(client, &local_err)) { | |
2556 | if (local_err) { | |
2557 | error_report_err(local_err); | |
2558 | } | |
2559 | client_close(client, false); | |
2560 | return; | |
2561 | } | |
2562 | ||
2563 | nbd_client_receive_next_request(client); | |
2564 | } | |
2565 | ||
2566 | /* | |
2567 | * Create a new client listener using the given channel @sioc. | |
2568 | * Begin servicing it in a coroutine. When the connection closes, call | |
2569 | * @close_fn with an indication of whether the client completed negotiation. | |
2570 | */ | |
2571 | void nbd_client_new(QIOChannelSocket *sioc, | |
2572 | QCryptoTLSCreds *tlscreds, | |
2573 | const char *tlsauthz, | |
2574 | void (*close_fn)(NBDClient *, bool)) | |
2575 | { | |
2576 | NBDClient *client; | |
2577 | Coroutine *co; | |
2578 | ||
2579 | client = g_new0(NBDClient, 1); | |
2580 | client->refcount = 1; | |
2581 | client->tlscreds = tlscreds; | |
2582 | if (tlscreds) { | |
2583 | object_ref(OBJECT(client->tlscreds)); | |
2584 | } | |
2585 | client->tlsauthz = g_strdup(tlsauthz); | |
2586 | client->sioc = sioc; | |
2587 | object_ref(OBJECT(client->sioc)); | |
2588 | client->ioc = QIO_CHANNEL(sioc); | |
2589 | object_ref(OBJECT(client->ioc)); | |
2590 | client->close_fn = close_fn; | |
2591 | ||
2592 | co = qemu_coroutine_create(nbd_co_client_start, client); | |
2593 | qemu_coroutine_enter(co); | |
2594 | } |