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Commit | Line | Data |
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75818250 | 1 | /* |
7a5ca864 FB |
2 | * Copyright (C) 2005 Anthony Liguori <[email protected]> |
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 | |
8167ee88 | 16 | * along with this program; if not, see <http://www.gnu.org/licenses/>. |
75818250 | 17 | */ |
7a5ca864 FB |
18 | |
19 | #include "nbd.h" | |
20 | ||
21 | #include <errno.h> | |
22 | #include <string.h> | |
03ff3ca3 | 23 | #ifndef _WIN32 |
7a5ca864 | 24 | #include <sys/ioctl.h> |
03ff3ca3 | 25 | #endif |
5dc2eec9 | 26 | #if defined(__sun__) || defined(__HAIKU__) |
7e00eb9b AL |
27 | #include <sys/ioccom.h> |
28 | #endif | |
7a5ca864 FB |
29 | #include <ctype.h> |
30 | #include <inttypes.h> | |
75818250 | 31 | |
03ff3ca3 AL |
32 | #include "qemu_socket.h" |
33 | ||
34 | //#define DEBUG_NBD | |
35 | ||
36 | #ifdef DEBUG_NBD | |
75818250 | 37 | #define TRACE(msg, ...) do { \ |
03ff3ca3 | 38 | LOG(msg, ## __VA_ARGS__); \ |
75818250 | 39 | } while(0) |
03ff3ca3 AL |
40 | #else |
41 | #define TRACE(msg, ...) \ | |
42 | do { } while (0) | |
43 | #endif | |
7a5ca864 FB |
44 | |
45 | #define LOG(msg, ...) do { \ | |
46 | fprintf(stderr, "%s:%s():L%d: " msg "\n", \ | |
47 | __FILE__, __FUNCTION__, __LINE__, ## __VA_ARGS__); \ | |
48 | } while(0) | |
49 | ||
7a5ca864 FB |
50 | /* This is all part of the "official" NBD API */ |
51 | ||
b2e3d87f | 52 | #define NBD_REPLY_SIZE (4 + 4 + 8) |
7a5ca864 FB |
53 | #define NBD_REQUEST_MAGIC 0x25609513 |
54 | #define NBD_REPLY_MAGIC 0x67446698 | |
55 | ||
56 | #define NBD_SET_SOCK _IO(0xab, 0) | |
57 | #define NBD_SET_BLKSIZE _IO(0xab, 1) | |
58 | #define NBD_SET_SIZE _IO(0xab, 2) | |
59 | #define NBD_DO_IT _IO(0xab, 3) | |
60 | #define NBD_CLEAR_SOCK _IO(0xab, 4) | |
61 | #define NBD_CLEAR_QUE _IO(0xab, 5) | |
b2e3d87f NT |
62 | #define NBD_PRINT_DEBUG _IO(0xab, 6) |
63 | #define NBD_SET_SIZE_BLOCKS _IO(0xab, 7) | |
7a5ca864 FB |
64 | #define NBD_DISCONNECT _IO(0xab, 8) |
65 | ||
b2e3d87f | 66 | #define NBD_OPT_EXPORT_NAME (1 << 0) |
1d45f8b5 | 67 | |
7a5ca864 FB |
68 | /* That's all folks */ |
69 | ||
75818250 TS |
70 | #define read_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, true) |
71 | #define write_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, false) | |
7a5ca864 | 72 | |
75818250 | 73 | size_t nbd_wr_sync(int fd, void *buffer, size_t size, bool do_read) |
7a5ca864 FB |
74 | { |
75 | size_t offset = 0; | |
76 | ||
77 | while (offset < size) { | |
78 | ssize_t len; | |
79 | ||
80 | if (do_read) { | |
03ff3ca3 | 81 | len = recv(fd, buffer + offset, size - offset, 0); |
7a5ca864 | 82 | } else { |
03ff3ca3 | 83 | len = send(fd, buffer + offset, size - offset, 0); |
7a5ca864 FB |
84 | } |
85 | ||
03ff3ca3 AL |
86 | if (len == -1) |
87 | errno = socket_error(); | |
88 | ||
7a5ca864 | 89 | /* recoverable error */ |
75818250 | 90 | if (len == -1 && (errno == EAGAIN || errno == EINTR)) { |
7a5ca864 FB |
91 | continue; |
92 | } | |
93 | ||
94 | /* eof */ | |
95 | if (len == 0) { | |
96 | break; | |
97 | } | |
98 | ||
99 | /* unrecoverable error */ | |
100 | if (len == -1) { | |
101 | return 0; | |
102 | } | |
103 | ||
104 | offset += len; | |
105 | } | |
106 | ||
107 | return offset; | |
108 | } | |
109 | ||
c12504ce NT |
110 | static void combine_addr(char *buf, size_t len, const char* address, |
111 | uint16_t port) | |
7a5ca864 | 112 | { |
c12504ce NT |
113 | /* If the address-part contains a colon, it's an IPv6 IP so needs [] */ |
114 | if (strstr(address, ":")) { | |
115 | snprintf(buf, len, "[%s]:%u", address, port); | |
116 | } else { | |
117 | snprintf(buf, len, "%s:%u", address, port); | |
7a5ca864 | 118 | } |
7a5ca864 FB |
119 | } |
120 | ||
c12504ce | 121 | int tcp_socket_outgoing(const char *address, uint16_t port) |
7a5ca864 | 122 | { |
c12504ce NT |
123 | char address_and_port[128]; |
124 | combine_addr(address_and_port, 128, address, port); | |
125 | return tcp_socket_outgoing_spec(address_and_port); | |
7a5ca864 FB |
126 | } |
127 | ||
c12504ce | 128 | int tcp_socket_outgoing_spec(const char *address_and_port) |
cd831bd7 | 129 | { |
c12504ce | 130 | return inet_connect(address_and_port, SOCK_STREAM); |
cd831bd7 TS |
131 | } |
132 | ||
c12504ce | 133 | int tcp_socket_incoming(const char *address, uint16_t port) |
cd831bd7 | 134 | { |
c12504ce NT |
135 | char address_and_port[128]; |
136 | combine_addr(address_and_port, 128, address, port); | |
137 | return tcp_socket_incoming_spec(address_and_port); | |
138 | } | |
cd831bd7 | 139 | |
c12504ce NT |
140 | int tcp_socket_incoming_spec(const char *address_and_port) |
141 | { | |
142 | char *ostr = NULL; | |
143 | int olen = 0; | |
144 | return inet_listen(address_and_port, ostr, olen, SOCK_STREAM, 0); | |
03ff3ca3 | 145 | } |
c12504ce | 146 | |
03ff3ca3 AL |
147 | int unix_socket_incoming(const char *path) |
148 | { | |
c12504ce NT |
149 | char *ostr = NULL; |
150 | int olen = 0; | |
151 | ||
152 | return unix_listen(path, ostr, olen); | |
cd831bd7 TS |
153 | } |
154 | ||
03ff3ca3 AL |
155 | int unix_socket_outgoing(const char *path) |
156 | { | |
c12504ce | 157 | return unix_connect(path); |
03ff3ca3 | 158 | } |
cd831bd7 | 159 | |
7a5ca864 FB |
160 | /* Basic flow |
161 | ||
162 | Server Client | |
163 | ||
164 | Negotiate | |
165 | Request | |
166 | Response | |
167 | Request | |
168 | Response | |
169 | ... | |
170 | ... | |
171 | Request (type == 2) | |
172 | */ | |
173 | ||
27982661 | 174 | int nbd_negotiate(int csock, off_t size) |
7a5ca864 | 175 | { |
b2e3d87f NT |
176 | char buf[8 + 8 + 8 + 128]; |
177 | ||
178 | /* Negotiate | |
179 | [ 0 .. 7] passwd ("NBDMAGIC") | |
180 | [ 8 .. 15] magic (0x00420281861253) | |
181 | [16 .. 23] size | |
182 | [24 .. 151] reserved (0) | |
183 | */ | |
184 | ||
185 | TRACE("Beginning negotiation."); | |
186 | memcpy(buf, "NBDMAGIC", 8); | |
187 | cpu_to_be64w((uint64_t*)(buf + 8), 0x00420281861253LL); | |
188 | cpu_to_be64w((uint64_t*)(buf + 16), size); | |
189 | memset(buf + 24, 0, 128); | |
190 | ||
191 | if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { | |
192 | LOG("write failed"); | |
193 | errno = EINVAL; | |
194 | return -1; | |
195 | } | |
196 | ||
197 | TRACE("Negotation succeeded."); | |
198 | ||
199 | return 0; | |
7a5ca864 FB |
200 | } |
201 | ||
1d45f8b5 LV |
202 | int nbd_receive_negotiate(int csock, const char *name, uint32_t *flags, |
203 | off_t *size, size_t *blocksize) | |
7a5ca864 | 204 | { |
b2e3d87f NT |
205 | char buf[256]; |
206 | uint64_t magic, s; | |
207 | uint16_t tmp; | |
208 | ||
209 | TRACE("Receiving negotation."); | |
210 | ||
211 | if (read_sync(csock, buf, 8) != 8) { | |
212 | LOG("read failed"); | |
213 | errno = EINVAL; | |
214 | return -1; | |
215 | } | |
216 | ||
217 | buf[8] = '\0'; | |
218 | if (strlen(buf) == 0) { | |
219 | LOG("server connection closed"); | |
220 | errno = EINVAL; | |
221 | return -1; | |
222 | } | |
223 | ||
224 | TRACE("Magic is %c%c%c%c%c%c%c%c", | |
225 | qemu_isprint(buf[0]) ? buf[0] : '.', | |
226 | qemu_isprint(buf[1]) ? buf[1] : '.', | |
227 | qemu_isprint(buf[2]) ? buf[2] : '.', | |
228 | qemu_isprint(buf[3]) ? buf[3] : '.', | |
229 | qemu_isprint(buf[4]) ? buf[4] : '.', | |
230 | qemu_isprint(buf[5]) ? buf[5] : '.', | |
231 | qemu_isprint(buf[6]) ? buf[6] : '.', | |
232 | qemu_isprint(buf[7]) ? buf[7] : '.'); | |
233 | ||
234 | if (memcmp(buf, "NBDMAGIC", 8) != 0) { | |
235 | LOG("Invalid magic received"); | |
236 | errno = EINVAL; | |
237 | return -1; | |
238 | } | |
239 | ||
240 | if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { | |
241 | LOG("read failed"); | |
242 | errno = EINVAL; | |
243 | return -1; | |
244 | } | |
245 | magic = be64_to_cpu(magic); | |
246 | TRACE("Magic is 0x%" PRIx64, magic); | |
247 | ||
248 | if (name) { | |
249 | uint32_t reserved = 0; | |
250 | uint32_t opt; | |
251 | uint32_t namesize; | |
252 | ||
253 | TRACE("Checking magic (opts_magic)"); | |
254 | if (magic != 0x49484156454F5054LL) { | |
255 | LOG("Bad magic received"); | |
256 | errno = EINVAL; | |
257 | return -1; | |
258 | } | |
259 | if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { | |
260 | LOG("flags read failed"); | |
261 | errno = EINVAL; | |
262 | return -1; | |
263 | } | |
264 | *flags = be16_to_cpu(tmp) << 16; | |
265 | /* reserved for future use */ | |
266 | if (write_sync(csock, &reserved, sizeof(reserved)) != | |
267 | sizeof(reserved)) { | |
268 | LOG("write failed (reserved)"); | |
269 | errno = EINVAL; | |
270 | return -1; | |
271 | } | |
272 | /* write the export name */ | |
273 | magic = cpu_to_be64(magic); | |
274 | if (write_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { | |
275 | LOG("write failed (magic)"); | |
276 | errno = EINVAL; | |
277 | return -1; | |
278 | } | |
279 | opt = cpu_to_be32(NBD_OPT_EXPORT_NAME); | |
280 | if (write_sync(csock, &opt, sizeof(opt)) != sizeof(opt)) { | |
281 | LOG("write failed (opt)"); | |
282 | errno = EINVAL; | |
283 | return -1; | |
284 | } | |
285 | namesize = cpu_to_be32(strlen(name)); | |
286 | if (write_sync(csock, &namesize, sizeof(namesize)) != | |
287 | sizeof(namesize)) { | |
288 | LOG("write failed (namesize)"); | |
289 | errno = EINVAL; | |
290 | return -1; | |
291 | } | |
292 | if (write_sync(csock, (char*)name, strlen(name)) != strlen(name)) { | |
293 | LOG("write failed (name)"); | |
294 | errno = EINVAL; | |
295 | return -1; | |
296 | } | |
297 | } else { | |
298 | TRACE("Checking magic (cli_magic)"); | |
299 | ||
300 | if (magic != 0x00420281861253LL) { | |
301 | LOG("Bad magic received"); | |
302 | errno = EINVAL; | |
303 | return -1; | |
304 | } | |
305 | } | |
306 | ||
307 | if (read_sync(csock, &s, sizeof(s)) != sizeof(s)) { | |
308 | LOG("read failed"); | |
309 | errno = EINVAL; | |
310 | return -1; | |
311 | } | |
312 | *size = be64_to_cpu(s); | |
313 | *blocksize = 1024; | |
314 | TRACE("Size is %" PRIu64, *size); | |
315 | ||
316 | if (!name) { | |
317 | if (read_sync(csock, flags, sizeof(*flags)) != sizeof(*flags)) { | |
318 | LOG("read failed (flags)"); | |
319 | errno = EINVAL; | |
320 | return -1; | |
321 | } | |
322 | *flags = be32_to_cpup(flags); | |
323 | } else { | |
324 | if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { | |
325 | LOG("read failed (tmp)"); | |
326 | errno = EINVAL; | |
327 | return -1; | |
328 | } | |
329 | *flags |= be32_to_cpu(tmp); | |
330 | } | |
331 | if (read_sync(csock, &buf, 124) != 124) { | |
332 | LOG("read failed (buf)"); | |
333 | errno = EINVAL; | |
334 | return -1; | |
335 | } | |
cd831bd7 TS |
336 | return 0; |
337 | } | |
7a5ca864 | 338 | |
03ff3ca3 | 339 | #ifndef _WIN32 |
cd831bd7 TS |
340 | int nbd_init(int fd, int csock, off_t size, size_t blocksize) |
341 | { | |
b2e3d87f | 342 | TRACE("Setting block size to %lu", (unsigned long)blocksize); |
7a5ca864 | 343 | |
b2e3d87f NT |
344 | if (ioctl(fd, NBD_SET_BLKSIZE, blocksize) == -1) { |
345 | int serrno = errno; | |
346 | LOG("Failed setting NBD block size"); | |
347 | errno = serrno; | |
348 | return -1; | |
349 | } | |
7a5ca864 | 350 | |
0bfcd599 | 351 | TRACE("Setting size to %zd block(s)", (size_t)(size / blocksize)); |
7a5ca864 | 352 | |
b2e3d87f NT |
353 | if (ioctl(fd, NBD_SET_SIZE_BLOCKS, size / blocksize) == -1) { |
354 | int serrno = errno; | |
355 | LOG("Failed setting size (in blocks)"); | |
356 | errno = serrno; | |
357 | return -1; | |
358 | } | |
7a5ca864 | 359 | |
b2e3d87f | 360 | TRACE("Clearing NBD socket"); |
7a5ca864 | 361 | |
b2e3d87f NT |
362 | if (ioctl(fd, NBD_CLEAR_SOCK) == -1) { |
363 | int serrno = errno; | |
364 | LOG("Failed clearing NBD socket"); | |
365 | errno = serrno; | |
366 | return -1; | |
367 | } | |
7a5ca864 | 368 | |
b2e3d87f | 369 | TRACE("Setting NBD socket"); |
7a5ca864 | 370 | |
b2e3d87f NT |
371 | if (ioctl(fd, NBD_SET_SOCK, csock) == -1) { |
372 | int serrno = errno; | |
373 | LOG("Failed to set NBD socket"); | |
374 | errno = serrno; | |
375 | return -1; | |
376 | } | |
7a5ca864 | 377 | |
b2e3d87f | 378 | TRACE("Negotiation ended"); |
7a5ca864 | 379 | |
b2e3d87f | 380 | return 0; |
7a5ca864 FB |
381 | } |
382 | ||
383 | int nbd_disconnect(int fd) | |
384 | { | |
b2e3d87f NT |
385 | ioctl(fd, NBD_CLEAR_QUE); |
386 | ioctl(fd, NBD_DISCONNECT); | |
387 | ioctl(fd, NBD_CLEAR_SOCK); | |
388 | return 0; | |
7a5ca864 FB |
389 | } |
390 | ||
0a4eb864 | 391 | int nbd_client(int fd) |
7a5ca864 | 392 | { |
b2e3d87f NT |
393 | int ret; |
394 | int serrno; | |
7a5ca864 | 395 | |
b2e3d87f | 396 | TRACE("Doing NBD loop"); |
7a5ca864 | 397 | |
b2e3d87f NT |
398 | ret = ioctl(fd, NBD_DO_IT); |
399 | serrno = errno; | |
7a5ca864 | 400 | |
b2e3d87f | 401 | TRACE("NBD loop returned %d: %s", ret, strerror(serrno)); |
7a5ca864 | 402 | |
b2e3d87f NT |
403 | TRACE("Clearing NBD queue"); |
404 | ioctl(fd, NBD_CLEAR_QUE); | |
7a5ca864 | 405 | |
b2e3d87f NT |
406 | TRACE("Clearing NBD socket"); |
407 | ioctl(fd, NBD_CLEAR_SOCK); | |
7a5ca864 | 408 | |
b2e3d87f NT |
409 | errno = serrno; |
410 | return ret; | |
7a5ca864 | 411 | } |
03ff3ca3 AL |
412 | #else |
413 | int nbd_init(int fd, int csock, off_t size, size_t blocksize) | |
414 | { | |
415 | errno = ENOTSUP; | |
416 | return -1; | |
417 | } | |
418 | ||
419 | int nbd_disconnect(int fd) | |
420 | { | |
421 | errno = ENOTSUP; | |
422 | return -1; | |
423 | } | |
424 | ||
0a4eb864 | 425 | int nbd_client(int fd) |
03ff3ca3 AL |
426 | { |
427 | errno = ENOTSUP; | |
428 | return -1; | |
429 | } | |
430 | #endif | |
7a5ca864 | 431 | |
75818250 | 432 | int nbd_send_request(int csock, struct nbd_request *request) |
7a5ca864 | 433 | { |
b2e3d87f NT |
434 | uint8_t buf[4 + 4 + 8 + 8 + 4]; |
435 | ||
436 | cpu_to_be32w((uint32_t*)buf, NBD_REQUEST_MAGIC); | |
437 | cpu_to_be32w((uint32_t*)(buf + 4), request->type); | |
438 | cpu_to_be64w((uint64_t*)(buf + 8), request->handle); | |
439 | cpu_to_be64w((uint64_t*)(buf + 16), request->from); | |
440 | cpu_to_be32w((uint32_t*)(buf + 24), request->len); | |
75818250 | 441 | |
b2e3d87f NT |
442 | TRACE("Sending request to client: " |
443 | "{ .from = %" PRIu64", .len = %u, .handle = %" PRIu64", .type=%i}", | |
444 | request->from, request->len, request->handle, request->type); | |
445 | ||
446 | if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { | |
447 | LOG("writing to socket failed"); | |
448 | errno = EINVAL; | |
449 | return -1; | |
450 | } | |
451 | return 0; | |
452 | } | |
75818250 TS |
453 | |
454 | static int nbd_receive_request(int csock, struct nbd_request *request) | |
455 | { | |
b2e3d87f NT |
456 | uint8_t buf[4 + 4 + 8 + 8 + 4]; |
457 | uint32_t magic; | |
458 | ||
459 | if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { | |
460 | LOG("read failed"); | |
461 | errno = EINVAL; | |
462 | return -1; | |
463 | } | |
464 | ||
465 | /* Request | |
466 | [ 0 .. 3] magic (NBD_REQUEST_MAGIC) | |
467 | [ 4 .. 7] type (0 == READ, 1 == WRITE) | |
468 | [ 8 .. 15] handle | |
469 | [16 .. 23] from | |
470 | [24 .. 27] len | |
471 | */ | |
472 | ||
473 | magic = be32_to_cpup((uint32_t*)buf); | |
474 | request->type = be32_to_cpup((uint32_t*)(buf + 4)); | |
475 | request->handle = be64_to_cpup((uint64_t*)(buf + 8)); | |
476 | request->from = be64_to_cpup((uint64_t*)(buf + 16)); | |
477 | request->len = be32_to_cpup((uint32_t*)(buf + 24)); | |
478 | ||
479 | TRACE("Got request: " | |
480 | "{ magic = 0x%x, .type = %d, from = %" PRIu64" , len = %u }", | |
481 | magic, request->type, request->from, request->len); | |
482 | ||
483 | if (magic != NBD_REQUEST_MAGIC) { | |
484 | LOG("invalid magic (got 0x%x)", magic); | |
485 | errno = EINVAL; | |
486 | return -1; | |
487 | } | |
488 | return 0; | |
75818250 TS |
489 | } |
490 | ||
491 | int nbd_receive_reply(int csock, struct nbd_reply *reply) | |
492 | { | |
b2e3d87f NT |
493 | uint8_t buf[NBD_REPLY_SIZE]; |
494 | uint32_t magic; | |
495 | ||
496 | memset(buf, 0xAA, sizeof(buf)); | |
497 | ||
498 | if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { | |
499 | LOG("read failed"); | |
500 | errno = EINVAL; | |
501 | return -1; | |
502 | } | |
503 | ||
504 | /* Reply | |
505 | [ 0 .. 3] magic (NBD_REPLY_MAGIC) | |
506 | [ 4 .. 7] error (0 == no error) | |
507 | [ 7 .. 15] handle | |
508 | */ | |
509 | ||
510 | magic = be32_to_cpup((uint32_t*)buf); | |
511 | reply->error = be32_to_cpup((uint32_t*)(buf + 4)); | |
512 | reply->handle = be64_to_cpup((uint64_t*)(buf + 8)); | |
513 | ||
514 | TRACE("Got reply: " | |
515 | "{ magic = 0x%x, .error = %d, handle = %" PRIu64" }", | |
516 | magic, reply->error, reply->handle); | |
517 | ||
518 | if (magic != NBD_REPLY_MAGIC) { | |
519 | LOG("invalid magic (got 0x%x)", magic); | |
520 | errno = EINVAL; | |
521 | return -1; | |
522 | } | |
523 | return 0; | |
75818250 TS |
524 | } |
525 | ||
526 | static int nbd_send_reply(int csock, struct nbd_reply *reply) | |
527 | { | |
b2e3d87f NT |
528 | uint8_t buf[4 + 4 + 8]; |
529 | ||
530 | /* Reply | |
531 | [ 0 .. 3] magic (NBD_REPLY_MAGIC) | |
532 | [ 4 .. 7] error (0 == no error) | |
533 | [ 7 .. 15] handle | |
534 | */ | |
535 | cpu_to_be32w((uint32_t*)buf, NBD_REPLY_MAGIC); | |
536 | cpu_to_be32w((uint32_t*)(buf + 4), reply->error); | |
537 | cpu_to_be64w((uint64_t*)(buf + 8), reply->handle); | |
538 | ||
539 | TRACE("Sending response to client"); | |
540 | ||
541 | if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { | |
542 | LOG("writing to socket failed"); | |
543 | errno = EINVAL; | |
544 | return -1; | |
545 | } | |
546 | return 0; | |
75818250 | 547 | } |
7a5ca864 | 548 | |
75818250 TS |
549 | int nbd_trip(BlockDriverState *bs, int csock, off_t size, uint64_t dev_offset, |
550 | off_t *offset, bool readonly, uint8_t *data, int data_size) | |
551 | { | |
b2e3d87f NT |
552 | struct nbd_request request; |
553 | struct nbd_reply reply; | |
554 | ||
555 | TRACE("Reading request."); | |
556 | ||
557 | if (nbd_receive_request(csock, &request) == -1) | |
558 | return -1; | |
559 | ||
560 | if (request.len + NBD_REPLY_SIZE > data_size) { | |
561 | LOG("len (%u) is larger than max len (%u)", | |
562 | request.len + NBD_REPLY_SIZE, data_size); | |
563 | errno = EINVAL; | |
564 | return -1; | |
565 | } | |
566 | ||
567 | if ((request.from + request.len) < request.from) { | |
568 | LOG("integer overflow detected! " | |
569 | "you're probably being attacked"); | |
570 | errno = EINVAL; | |
571 | return -1; | |
572 | } | |
573 | ||
574 | if ((request.from + request.len) > size) { | |
575 | LOG("From: %" PRIu64 ", Len: %u, Size: %" PRIu64 | |
576 | ", Offset: %" PRIu64 "\n", | |
b9e82a59 | 577 | request.from, request.len, (uint64_t)size, dev_offset); |
b2e3d87f NT |
578 | LOG("requested operation past EOF--bad client?"); |
579 | errno = EINVAL; | |
580 | return -1; | |
581 | } | |
582 | ||
583 | TRACE("Decoding type"); | |
584 | ||
585 | reply.handle = request.handle; | |
586 | reply.error = 0; | |
587 | ||
588 | switch (request.type) { | |
589 | case NBD_CMD_READ: | |
590 | TRACE("Request type is READ"); | |
591 | ||
592 | if (bdrv_read(bs, (request.from + dev_offset) / 512, | |
593 | data + NBD_REPLY_SIZE, | |
594 | request.len / 512) == -1) { | |
595 | LOG("reading from file failed"); | |
596 | errno = EINVAL; | |
597 | return -1; | |
598 | } | |
599 | *offset += request.len; | |
600 | ||
601 | TRACE("Read %u byte(s)", request.len); | |
602 | ||
603 | /* Reply | |
604 | [ 0 .. 3] magic (NBD_REPLY_MAGIC) | |
605 | [ 4 .. 7] error (0 == no error) | |
606 | [ 7 .. 15] handle | |
607 | */ | |
608 | ||
609 | cpu_to_be32w((uint32_t*)data, NBD_REPLY_MAGIC); | |
610 | cpu_to_be32w((uint32_t*)(data + 4), reply.error); | |
611 | cpu_to_be64w((uint64_t*)(data + 8), reply.handle); | |
612 | ||
613 | TRACE("Sending data to client"); | |
614 | ||
615 | if (write_sync(csock, data, | |
616 | request.len + NBD_REPLY_SIZE) != | |
617 | request.len + NBD_REPLY_SIZE) { | |
618 | LOG("writing to socket failed"); | |
619 | errno = EINVAL; | |
620 | return -1; | |
621 | } | |
622 | break; | |
623 | case NBD_CMD_WRITE: | |
624 | TRACE("Request type is WRITE"); | |
625 | ||
626 | TRACE("Reading %u byte(s)", request.len); | |
627 | ||
628 | if (read_sync(csock, data, request.len) != request.len) { | |
629 | LOG("reading from socket failed"); | |
630 | errno = EINVAL; | |
631 | return -1; | |
632 | } | |
633 | ||
634 | if (readonly) { | |
635 | TRACE("Server is read-only, return error"); | |
636 | reply.error = 1; | |
637 | } else { | |
638 | TRACE("Writing to device"); | |
639 | ||
640 | if (bdrv_write(bs, (request.from + dev_offset) / 512, | |
641 | data, request.len / 512) == -1) { | |
642 | LOG("writing to file failed"); | |
643 | errno = EINVAL; | |
644 | return -1; | |
645 | } | |
646 | ||
647 | *offset += request.len; | |
648 | } | |
649 | ||
650 | if (nbd_send_reply(csock, &reply) == -1) | |
651 | return -1; | |
652 | break; | |
653 | case NBD_CMD_DISC: | |
654 | TRACE("Request type is DISCONNECT"); | |
655 | errno = 0; | |
656 | return 1; | |
657 | default: | |
658 | LOG("invalid request type (%u) received", request.type); | |
659 | errno = EINVAL; | |
660 | return -1; | |
661 | } | |
662 | ||
663 | TRACE("Request/Reply complete"); | |
664 | ||
665 | return 0; | |
7a5ca864 | 666 | } |