root / nbd.c @ 3777b09f
History | View | Annotate | Download (18.9 kB)
1 |
/*
|
---|---|
2 |
* Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
|
3 |
*
|
4 |
* Network Block Device
|
5 |
*
|
6 |
* This program is free software; you can redistribute it and/or modify
|
7 |
* it under the terms of the GNU General Public License as published by
|
8 |
* the Free Software Foundation; under version 2 of the License.
|
9 |
*
|
10 |
* This program is distributed in the hope that it will be useful,
|
11 |
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
12 |
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
13 |
* GNU General Public License for more details.
|
14 |
*
|
15 |
* You should have received a copy of the GNU General Public License
|
16 |
* along with this program; if not, see <http://www.gnu.org/licenses/>.
|
17 |
*/
|
18 |
|
19 |
#include "nbd.h" |
20 |
#include "block.h" |
21 |
|
22 |
#include <errno.h> |
23 |
#include <string.h> |
24 |
#ifndef _WIN32
|
25 |
#include <sys/ioctl.h> |
26 |
#endif
|
27 |
#if defined(__sun__) || defined(__HAIKU__)
|
28 |
#include <sys/ioccom.h> |
29 |
#endif
|
30 |
#include <ctype.h> |
31 |
#include <inttypes.h> |
32 |
|
33 |
#ifdef __linux__
|
34 |
#include <linux/fs.h> |
35 |
#endif
|
36 |
|
37 |
#include "qemu_socket.h" |
38 |
|
39 |
//#define DEBUG_NBD
|
40 |
|
41 |
#ifdef DEBUG_NBD
|
42 |
#define TRACE(msg, ...) do { \ |
43 |
LOG(msg, ## __VA_ARGS__); \ |
44 |
} while(0) |
45 |
#else
|
46 |
#define TRACE(msg, ...) \
|
47 |
do { } while (0) |
48 |
#endif
|
49 |
|
50 |
#define LOG(msg, ...) do { \ |
51 |
fprintf(stderr, "%s:%s():L%d: " msg "\n", \ |
52 |
__FILE__, __FUNCTION__, __LINE__, ## __VA_ARGS__); \ |
53 |
} while(0) |
54 |
|
55 |
/* This is all part of the "official" NBD API */
|
56 |
|
57 |
#define NBD_REPLY_SIZE (4 + 4 + 8) |
58 |
#define NBD_REQUEST_MAGIC 0x25609513 |
59 |
#define NBD_REPLY_MAGIC 0x67446698 |
60 |
|
61 |
#define NBD_SET_SOCK _IO(0xab, 0) |
62 |
#define NBD_SET_BLKSIZE _IO(0xab, 1) |
63 |
#define NBD_SET_SIZE _IO(0xab, 2) |
64 |
#define NBD_DO_IT _IO(0xab, 3) |
65 |
#define NBD_CLEAR_SOCK _IO(0xab, 4) |
66 |
#define NBD_CLEAR_QUE _IO(0xab, 5) |
67 |
#define NBD_PRINT_DEBUG _IO(0xab, 6) |
68 |
#define NBD_SET_SIZE_BLOCKS _IO(0xab, 7) |
69 |
#define NBD_DISCONNECT _IO(0xab, 8) |
70 |
#define NBD_SET_TIMEOUT _IO(0xab, 9) |
71 |
#define NBD_SET_FLAGS _IO(0xab, 10) |
72 |
|
73 |
#define NBD_OPT_EXPORT_NAME (1 << 0) |
74 |
|
75 |
/* That's all folks */
|
76 |
|
77 |
#define read_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, true) |
78 |
#define write_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, false) |
79 |
|
80 |
size_t nbd_wr_sync(int fd, void *buffer, size_t size, bool do_read) |
81 |
{ |
82 |
size_t offset = 0;
|
83 |
|
84 |
if (qemu_in_coroutine()) {
|
85 |
if (do_read) {
|
86 |
return qemu_co_recv(fd, buffer, size);
|
87 |
} else {
|
88 |
return qemu_co_send(fd, buffer, size);
|
89 |
} |
90 |
} |
91 |
|
92 |
while (offset < size) {
|
93 |
ssize_t len; |
94 |
|
95 |
if (do_read) {
|
96 |
len = qemu_recv(fd, buffer + offset, size - offset, 0);
|
97 |
} else {
|
98 |
len = send(fd, buffer + offset, size - offset, 0);
|
99 |
} |
100 |
|
101 |
if (len == -1) |
102 |
errno = socket_error(); |
103 |
|
104 |
/* recoverable error */
|
105 |
if (len == -1 && (errno == EAGAIN || errno == EINTR)) { |
106 |
continue;
|
107 |
} |
108 |
|
109 |
/* eof */
|
110 |
if (len == 0) { |
111 |
break;
|
112 |
} |
113 |
|
114 |
/* unrecoverable error */
|
115 |
if (len == -1) { |
116 |
return 0; |
117 |
} |
118 |
|
119 |
offset += len; |
120 |
} |
121 |
|
122 |
return offset;
|
123 |
} |
124 |
|
125 |
static void combine_addr(char *buf, size_t len, const char* address, |
126 |
uint16_t port) |
127 |
{ |
128 |
/* If the address-part contains a colon, it's an IPv6 IP so needs [] */
|
129 |
if (strstr(address, ":")) { |
130 |
snprintf(buf, len, "[%s]:%u", address, port);
|
131 |
} else {
|
132 |
snprintf(buf, len, "%s:%u", address, port);
|
133 |
} |
134 |
} |
135 |
|
136 |
int tcp_socket_outgoing(const char *address, uint16_t port) |
137 |
{ |
138 |
char address_and_port[128]; |
139 |
combine_addr(address_and_port, 128, address, port);
|
140 |
return tcp_socket_outgoing_spec(address_and_port);
|
141 |
} |
142 |
|
143 |
int tcp_socket_outgoing_spec(const char *address_and_port) |
144 |
{ |
145 |
return inet_connect(address_and_port, SOCK_STREAM);
|
146 |
} |
147 |
|
148 |
int tcp_socket_incoming(const char *address, uint16_t port) |
149 |
{ |
150 |
char address_and_port[128]; |
151 |
combine_addr(address_and_port, 128, address, port);
|
152 |
return tcp_socket_incoming_spec(address_and_port);
|
153 |
} |
154 |
|
155 |
int tcp_socket_incoming_spec(const char *address_and_port) |
156 |
{ |
157 |
char *ostr = NULL; |
158 |
int olen = 0; |
159 |
return inet_listen(address_and_port, ostr, olen, SOCK_STREAM, 0); |
160 |
} |
161 |
|
162 |
int unix_socket_incoming(const char *path) |
163 |
{ |
164 |
char *ostr = NULL; |
165 |
int olen = 0; |
166 |
|
167 |
return unix_listen(path, ostr, olen);
|
168 |
} |
169 |
|
170 |
int unix_socket_outgoing(const char *path) |
171 |
{ |
172 |
return unix_connect(path);
|
173 |
} |
174 |
|
175 |
/* Basic flow
|
176 |
|
177 |
Server Client
|
178 |
|
179 |
Negotiate
|
180 |
Request
|
181 |
Response
|
182 |
Request
|
183 |
Response
|
184 |
...
|
185 |
...
|
186 |
Request (type == 2)
|
187 |
*/
|
188 |
|
189 |
int nbd_negotiate(int csock, off_t size, uint32_t flags) |
190 |
{ |
191 |
char buf[8 + 8 + 8 + 128]; |
192 |
|
193 |
/* Negotiate
|
194 |
[ 0 .. 7] passwd ("NBDMAGIC")
|
195 |
[ 8 .. 15] magic (0x00420281861253)
|
196 |
[16 .. 23] size
|
197 |
[24 .. 27] flags
|
198 |
[28 .. 151] reserved (0)
|
199 |
*/
|
200 |
|
201 |
TRACE("Beginning negotiation.");
|
202 |
memcpy(buf, "NBDMAGIC", 8); |
203 |
cpu_to_be64w((uint64_t*)(buf + 8), 0x00420281861253LL); |
204 |
cpu_to_be64w((uint64_t*)(buf + 16), size);
|
205 |
cpu_to_be32w((uint32_t*)(buf + 24),
|
206 |
flags | NBD_FLAG_HAS_FLAGS | NBD_FLAG_SEND_TRIM | |
207 |
NBD_FLAG_SEND_FLUSH | NBD_FLAG_SEND_FUA); |
208 |
memset(buf + 28, 0, 124); |
209 |
|
210 |
if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
211 |
LOG("write failed");
|
212 |
errno = EINVAL; |
213 |
return -1; |
214 |
} |
215 |
|
216 |
TRACE("Negotiation succeeded.");
|
217 |
|
218 |
return 0; |
219 |
} |
220 |
|
221 |
int nbd_receive_negotiate(int csock, const char *name, uint32_t *flags, |
222 |
off_t *size, size_t *blocksize) |
223 |
{ |
224 |
char buf[256]; |
225 |
uint64_t magic, s; |
226 |
uint16_t tmp; |
227 |
|
228 |
TRACE("Receiving negotiation.");
|
229 |
|
230 |
if (read_sync(csock, buf, 8) != 8) { |
231 |
LOG("read failed");
|
232 |
errno = EINVAL; |
233 |
return -1; |
234 |
} |
235 |
|
236 |
buf[8] = '\0'; |
237 |
if (strlen(buf) == 0) { |
238 |
LOG("server connection closed");
|
239 |
errno = EINVAL; |
240 |
return -1; |
241 |
} |
242 |
|
243 |
TRACE("Magic is %c%c%c%c%c%c%c%c",
|
244 |
qemu_isprint(buf[0]) ? buf[0] : '.', |
245 |
qemu_isprint(buf[1]) ? buf[1] : '.', |
246 |
qemu_isprint(buf[2]) ? buf[2] : '.', |
247 |
qemu_isprint(buf[3]) ? buf[3] : '.', |
248 |
qemu_isprint(buf[4]) ? buf[4] : '.', |
249 |
qemu_isprint(buf[5]) ? buf[5] : '.', |
250 |
qemu_isprint(buf[6]) ? buf[6] : '.', |
251 |
qemu_isprint(buf[7]) ? buf[7] : '.'); |
252 |
|
253 |
if (memcmp(buf, "NBDMAGIC", 8) != 0) { |
254 |
LOG("Invalid magic received");
|
255 |
errno = EINVAL; |
256 |
return -1; |
257 |
} |
258 |
|
259 |
if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { |
260 |
LOG("read failed");
|
261 |
errno = EINVAL; |
262 |
return -1; |
263 |
} |
264 |
magic = be64_to_cpu(magic); |
265 |
TRACE("Magic is 0x%" PRIx64, magic);
|
266 |
|
267 |
if (name) {
|
268 |
uint32_t reserved = 0;
|
269 |
uint32_t opt; |
270 |
uint32_t namesize; |
271 |
|
272 |
TRACE("Checking magic (opts_magic)");
|
273 |
if (magic != 0x49484156454F5054LL) { |
274 |
LOG("Bad magic received");
|
275 |
errno = EINVAL; |
276 |
return -1; |
277 |
} |
278 |
if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { |
279 |
LOG("flags read failed");
|
280 |
errno = EINVAL; |
281 |
return -1; |
282 |
} |
283 |
*flags = be16_to_cpu(tmp) << 16;
|
284 |
/* reserved for future use */
|
285 |
if (write_sync(csock, &reserved, sizeof(reserved)) != |
286 |
sizeof(reserved)) {
|
287 |
LOG("write failed (reserved)");
|
288 |
errno = EINVAL; |
289 |
return -1; |
290 |
} |
291 |
/* write the export name */
|
292 |
magic = cpu_to_be64(magic); |
293 |
if (write_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { |
294 |
LOG("write failed (magic)");
|
295 |
errno = EINVAL; |
296 |
return -1; |
297 |
} |
298 |
opt = cpu_to_be32(NBD_OPT_EXPORT_NAME); |
299 |
if (write_sync(csock, &opt, sizeof(opt)) != sizeof(opt)) { |
300 |
LOG("write failed (opt)");
|
301 |
errno = EINVAL; |
302 |
return -1; |
303 |
} |
304 |
namesize = cpu_to_be32(strlen(name)); |
305 |
if (write_sync(csock, &namesize, sizeof(namesize)) != |
306 |
sizeof(namesize)) {
|
307 |
LOG("write failed (namesize)");
|
308 |
errno = EINVAL; |
309 |
return -1; |
310 |
} |
311 |
if (write_sync(csock, (char*)name, strlen(name)) != strlen(name)) { |
312 |
LOG("write failed (name)");
|
313 |
errno = EINVAL; |
314 |
return -1; |
315 |
} |
316 |
} else {
|
317 |
TRACE("Checking magic (cli_magic)");
|
318 |
|
319 |
if (magic != 0x00420281861253LL) { |
320 |
LOG("Bad magic received");
|
321 |
errno = EINVAL; |
322 |
return -1; |
323 |
} |
324 |
} |
325 |
|
326 |
if (read_sync(csock, &s, sizeof(s)) != sizeof(s)) { |
327 |
LOG("read failed");
|
328 |
errno = EINVAL; |
329 |
return -1; |
330 |
} |
331 |
*size = be64_to_cpu(s); |
332 |
*blocksize = 1024;
|
333 |
TRACE("Size is %" PRIu64, *size);
|
334 |
|
335 |
if (!name) {
|
336 |
if (read_sync(csock, flags, sizeof(*flags)) != sizeof(*flags)) { |
337 |
LOG("read failed (flags)");
|
338 |
errno = EINVAL; |
339 |
return -1; |
340 |
} |
341 |
*flags = be32_to_cpup(flags); |
342 |
} else {
|
343 |
if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { |
344 |
LOG("read failed (tmp)");
|
345 |
errno = EINVAL; |
346 |
return -1; |
347 |
} |
348 |
*flags |= be32_to_cpu(tmp); |
349 |
} |
350 |
if (read_sync(csock, &buf, 124) != 124) { |
351 |
LOG("read failed (buf)");
|
352 |
errno = EINVAL; |
353 |
return -1; |
354 |
} |
355 |
return 0; |
356 |
} |
357 |
|
358 |
#ifdef __linux__
|
359 |
int nbd_init(int fd, int csock, uint32_t flags, off_t size, size_t blocksize) |
360 |
{ |
361 |
TRACE("Setting NBD socket");
|
362 |
|
363 |
if (ioctl(fd, NBD_SET_SOCK, csock) == -1) { |
364 |
int serrno = errno;
|
365 |
LOG("Failed to set NBD socket");
|
366 |
errno = serrno; |
367 |
return -1; |
368 |
} |
369 |
|
370 |
TRACE("Setting block size to %lu", (unsigned long)blocksize); |
371 |
|
372 |
if (ioctl(fd, NBD_SET_BLKSIZE, blocksize) == -1) { |
373 |
int serrno = errno;
|
374 |
LOG("Failed setting NBD block size");
|
375 |
errno = serrno; |
376 |
return -1; |
377 |
} |
378 |
|
379 |
TRACE("Setting size to %zd block(s)", (size_t)(size / blocksize));
|
380 |
|
381 |
if (ioctl(fd, NBD_SET_SIZE_BLOCKS, size / blocksize) == -1) { |
382 |
int serrno = errno;
|
383 |
LOG("Failed setting size (in blocks)");
|
384 |
errno = serrno; |
385 |
return -1; |
386 |
} |
387 |
|
388 |
if (flags & NBD_FLAG_READ_ONLY) {
|
389 |
int read_only = 1; |
390 |
TRACE("Setting readonly attribute");
|
391 |
|
392 |
if (ioctl(fd, BLKROSET, (unsigned long) &read_only) < 0) { |
393 |
int serrno = errno;
|
394 |
LOG("Failed setting read-only attribute");
|
395 |
errno = serrno; |
396 |
return -1; |
397 |
} |
398 |
} |
399 |
|
400 |
if (ioctl(fd, NBD_SET_FLAGS, flags) < 0 |
401 |
&& errno != ENOTTY) { |
402 |
int serrno = errno;
|
403 |
LOG("Failed setting flags");
|
404 |
errno = serrno; |
405 |
return -1; |
406 |
} |
407 |
|
408 |
TRACE("Negotiation ended");
|
409 |
|
410 |
return 0; |
411 |
} |
412 |
|
413 |
int nbd_disconnect(int fd) |
414 |
{ |
415 |
ioctl(fd, NBD_CLEAR_QUE); |
416 |
ioctl(fd, NBD_DISCONNECT); |
417 |
ioctl(fd, NBD_CLEAR_SOCK); |
418 |
return 0; |
419 |
} |
420 |
|
421 |
int nbd_client(int fd) |
422 |
{ |
423 |
int ret;
|
424 |
int serrno;
|
425 |
|
426 |
TRACE("Doing NBD loop");
|
427 |
|
428 |
ret = ioctl(fd, NBD_DO_IT); |
429 |
if (ret == -1 && errno == EPIPE) { |
430 |
/* NBD_DO_IT normally returns EPIPE when someone has disconnected
|
431 |
* the socket via NBD_DISCONNECT. We do not want to return 1 in
|
432 |
* that case.
|
433 |
*/
|
434 |
ret = 0;
|
435 |
} |
436 |
serrno = errno; |
437 |
|
438 |
TRACE("NBD loop returned %d: %s", ret, strerror(serrno));
|
439 |
|
440 |
TRACE("Clearing NBD queue");
|
441 |
ioctl(fd, NBD_CLEAR_QUE); |
442 |
|
443 |
TRACE("Clearing NBD socket");
|
444 |
ioctl(fd, NBD_CLEAR_SOCK); |
445 |
|
446 |
errno = serrno; |
447 |
return ret;
|
448 |
} |
449 |
#else
|
450 |
int nbd_init(int fd, int csock, uint32_t flags, off_t size, size_t blocksize) |
451 |
{ |
452 |
errno = ENOTSUP; |
453 |
return -1; |
454 |
} |
455 |
|
456 |
int nbd_disconnect(int fd) |
457 |
{ |
458 |
errno = ENOTSUP; |
459 |
return -1; |
460 |
} |
461 |
|
462 |
int nbd_client(int fd) |
463 |
{ |
464 |
errno = ENOTSUP; |
465 |
return -1; |
466 |
} |
467 |
#endif
|
468 |
|
469 |
int nbd_send_request(int csock, struct nbd_request *request) |
470 |
{ |
471 |
uint8_t buf[4 + 4 + 8 + 8 + 4]; |
472 |
|
473 |
cpu_to_be32w((uint32_t*)buf, NBD_REQUEST_MAGIC); |
474 |
cpu_to_be32w((uint32_t*)(buf + 4), request->type);
|
475 |
cpu_to_be64w((uint64_t*)(buf + 8), request->handle);
|
476 |
cpu_to_be64w((uint64_t*)(buf + 16), request->from);
|
477 |
cpu_to_be32w((uint32_t*)(buf + 24), request->len);
|
478 |
|
479 |
TRACE("Sending request to client: "
|
480 |
"{ .from = %" PRIu64", .len = %u, .handle = %" PRIu64", .type=%i}", |
481 |
request->from, request->len, request->handle, request->type); |
482 |
|
483 |
if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
484 |
LOG("writing to socket failed");
|
485 |
errno = EINVAL; |
486 |
return -1; |
487 |
} |
488 |
return 0; |
489 |
} |
490 |
|
491 |
static int nbd_receive_request(int csock, struct nbd_request *request) |
492 |
{ |
493 |
uint8_t buf[4 + 4 + 8 + 8 + 4]; |
494 |
uint32_t magic; |
495 |
|
496 |
if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
497 |
LOG("read failed");
|
498 |
errno = EINVAL; |
499 |
return -1; |
500 |
} |
501 |
|
502 |
/* Request
|
503 |
[ 0 .. 3] magic (NBD_REQUEST_MAGIC)
|
504 |
[ 4 .. 7] type (0 == READ, 1 == WRITE)
|
505 |
[ 8 .. 15] handle
|
506 |
[16 .. 23] from
|
507 |
[24 .. 27] len
|
508 |
*/
|
509 |
|
510 |
magic = be32_to_cpup((uint32_t*)buf); |
511 |
request->type = be32_to_cpup((uint32_t*)(buf + 4));
|
512 |
request->handle = be64_to_cpup((uint64_t*)(buf + 8));
|
513 |
request->from = be64_to_cpup((uint64_t*)(buf + 16));
|
514 |
request->len = be32_to_cpup((uint32_t*)(buf + 24));
|
515 |
|
516 |
TRACE("Got request: "
|
517 |
"{ magic = 0x%x, .type = %d, from = %" PRIu64" , len = %u }", |
518 |
magic, request->type, request->from, request->len); |
519 |
|
520 |
if (magic != NBD_REQUEST_MAGIC) {
|
521 |
LOG("invalid magic (got 0x%x)", magic);
|
522 |
errno = EINVAL; |
523 |
return -1; |
524 |
} |
525 |
return 0; |
526 |
} |
527 |
|
528 |
int nbd_receive_reply(int csock, struct nbd_reply *reply) |
529 |
{ |
530 |
uint8_t buf[NBD_REPLY_SIZE]; |
531 |
uint32_t magic; |
532 |
|
533 |
memset(buf, 0xAA, sizeof(buf)); |
534 |
|
535 |
if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
536 |
LOG("read failed");
|
537 |
errno = EINVAL; |
538 |
return -1; |
539 |
} |
540 |
|
541 |
/* Reply
|
542 |
[ 0 .. 3] magic (NBD_REPLY_MAGIC)
|
543 |
[ 4 .. 7] error (0 == no error)
|
544 |
[ 7 .. 15] handle
|
545 |
*/
|
546 |
|
547 |
magic = be32_to_cpup((uint32_t*)buf); |
548 |
reply->error = be32_to_cpup((uint32_t*)(buf + 4));
|
549 |
reply->handle = be64_to_cpup((uint64_t*)(buf + 8));
|
550 |
|
551 |
TRACE("Got reply: "
|
552 |
"{ magic = 0x%x, .error = %d, handle = %" PRIu64" }", |
553 |
magic, reply->error, reply->handle); |
554 |
|
555 |
if (magic != NBD_REPLY_MAGIC) {
|
556 |
LOG("invalid magic (got 0x%x)", magic);
|
557 |
errno = EINVAL; |
558 |
return -1; |
559 |
} |
560 |
return 0; |
561 |
} |
562 |
|
563 |
static int nbd_send_reply(int csock, struct nbd_reply *reply) |
564 |
{ |
565 |
uint8_t buf[4 + 4 + 8]; |
566 |
|
567 |
/* Reply
|
568 |
[ 0 .. 3] magic (NBD_REPLY_MAGIC)
|
569 |
[ 4 .. 7] error (0 == no error)
|
570 |
[ 7 .. 15] handle
|
571 |
*/
|
572 |
cpu_to_be32w((uint32_t*)buf, NBD_REPLY_MAGIC); |
573 |
cpu_to_be32w((uint32_t*)(buf + 4), reply->error);
|
574 |
cpu_to_be64w((uint64_t*)(buf + 8), reply->handle);
|
575 |
|
576 |
TRACE("Sending response to client");
|
577 |
|
578 |
if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
579 |
LOG("writing to socket failed");
|
580 |
errno = EINVAL; |
581 |
return -1; |
582 |
} |
583 |
return 0; |
584 |
} |
585 |
|
586 |
int nbd_trip(BlockDriverState *bs, int csock, off_t size, |
587 |
uint64_t dev_offset, uint32_t nbdflags, |
588 |
uint8_t *data) |
589 |
{ |
590 |
struct nbd_request request;
|
591 |
struct nbd_reply reply;
|
592 |
int ret;
|
593 |
|
594 |
TRACE("Reading request.");
|
595 |
|
596 |
if (nbd_receive_request(csock, &request) == -1) |
597 |
return -1; |
598 |
|
599 |
if (request.len + NBD_REPLY_SIZE > NBD_BUFFER_SIZE) {
|
600 |
LOG("len (%u) is larger than max len (%u)",
|
601 |
request.len + NBD_REPLY_SIZE, NBD_BUFFER_SIZE); |
602 |
errno = EINVAL; |
603 |
return -1; |
604 |
} |
605 |
|
606 |
if ((request.from + request.len) < request.from) {
|
607 |
LOG("integer overflow detected! "
|
608 |
"you're probably being attacked");
|
609 |
errno = EINVAL; |
610 |
return -1; |
611 |
} |
612 |
|
613 |
if ((request.from + request.len) > size) {
|
614 |
LOG("From: %" PRIu64 ", Len: %u, Size: %" PRIu64 |
615 |
", Offset: %" PRIu64 "\n", |
616 |
request.from, request.len, (uint64_t)size, dev_offset); |
617 |
LOG("requested operation past EOF--bad client?");
|
618 |
errno = EINVAL; |
619 |
return -1; |
620 |
} |
621 |
|
622 |
TRACE("Decoding type");
|
623 |
|
624 |
reply.handle = request.handle; |
625 |
reply.error = 0;
|
626 |
|
627 |
switch (request.type & NBD_CMD_MASK_COMMAND) {
|
628 |
case NBD_CMD_READ:
|
629 |
TRACE("Request type is READ");
|
630 |
|
631 |
ret = bdrv_read(bs, (request.from + dev_offset) / 512,
|
632 |
data + NBD_REPLY_SIZE, |
633 |
request.len / 512);
|
634 |
if (ret < 0) { |
635 |
LOG("reading from file failed");
|
636 |
reply.error = -ret; |
637 |
request.len = 0;
|
638 |
} |
639 |
|
640 |
TRACE("Read %u byte(s)", request.len);
|
641 |
|
642 |
/* Reply
|
643 |
[ 0 .. 3] magic (NBD_REPLY_MAGIC)
|
644 |
[ 4 .. 7] error (0 == no error)
|
645 |
[ 7 .. 15] handle
|
646 |
*/
|
647 |
|
648 |
cpu_to_be32w((uint32_t*)data, NBD_REPLY_MAGIC); |
649 |
cpu_to_be32w((uint32_t*)(data + 4), reply.error);
|
650 |
cpu_to_be64w((uint64_t*)(data + 8), reply.handle);
|
651 |
|
652 |
TRACE("Sending data to client");
|
653 |
|
654 |
if (write_sync(csock, data,
|
655 |
request.len + NBD_REPLY_SIZE) != |
656 |
request.len + NBD_REPLY_SIZE) { |
657 |
LOG("writing to socket failed");
|
658 |
errno = EINVAL; |
659 |
return -1; |
660 |
} |
661 |
break;
|
662 |
case NBD_CMD_WRITE:
|
663 |
TRACE("Request type is WRITE");
|
664 |
|
665 |
TRACE("Reading %u byte(s)", request.len);
|
666 |
|
667 |
if (read_sync(csock, data, request.len) != request.len) {
|
668 |
LOG("reading from socket failed");
|
669 |
errno = EINVAL; |
670 |
return -1; |
671 |
} |
672 |
|
673 |
if (nbdflags & NBD_FLAG_READ_ONLY) {
|
674 |
TRACE("Server is read-only, return error");
|
675 |
reply.error = 1;
|
676 |
} else {
|
677 |
TRACE("Writing to device");
|
678 |
|
679 |
ret = bdrv_write(bs, (request.from + dev_offset) / 512,
|
680 |
data, request.len / 512);
|
681 |
if (ret < 0) { |
682 |
LOG("writing to file failed");
|
683 |
reply.error = -ret; |
684 |
request.len = 0;
|
685 |
} |
686 |
|
687 |
if (request.type & NBD_CMD_FLAG_FUA) {
|
688 |
ret = bdrv_flush(bs); |
689 |
if (ret < 0) { |
690 |
LOG("flush failed");
|
691 |
reply.error = -ret; |
692 |
} |
693 |
} |
694 |
} |
695 |
|
696 |
if (nbd_send_reply(csock, &reply) == -1) |
697 |
return -1; |
698 |
break;
|
699 |
case NBD_CMD_DISC:
|
700 |
TRACE("Request type is DISCONNECT");
|
701 |
errno = 0;
|
702 |
return 1; |
703 |
case NBD_CMD_FLUSH:
|
704 |
TRACE("Request type is FLUSH");
|
705 |
|
706 |
ret = bdrv_flush(bs); |
707 |
if (ret < 0) { |
708 |
LOG("flush failed");
|
709 |
reply.error = -ret; |
710 |
} |
711 |
|
712 |
if (nbd_send_reply(csock, &reply) == -1) |
713 |
return -1; |
714 |
break;
|
715 |
case NBD_CMD_TRIM:
|
716 |
TRACE("Request type is TRIM");
|
717 |
ret = bdrv_discard(bs, (request.from + dev_offset) / 512,
|
718 |
request.len / 512);
|
719 |
if (ret < 0) { |
720 |
LOG("discard failed");
|
721 |
reply.error = -ret; |
722 |
} |
723 |
if (nbd_send_reply(csock, &reply) == -1) |
724 |
return -1; |
725 |
break;
|
726 |
default:
|
727 |
LOG("invalid request type (%u) received", request.type);
|
728 |
errno = EINVAL; |
729 |
return -1; |
730 |
} |
731 |
|
732 |
TRACE("Request/Reply complete");
|
733 |
|
734 |
return 0; |
735 |
} |