root / nbd.c @ 0a4eb864
History | View | Annotate | Download (13.9 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 |
|
| 21 |
#include <errno.h> |
| 22 |
#include <string.h> |
| 23 |
#ifndef _WIN32
|
| 24 |
#include <sys/ioctl.h> |
| 25 |
#endif
|
| 26 |
#ifdef __sun__
|
| 27 |
#include <sys/ioccom.h> |
| 28 |
#endif
|
| 29 |
#include <ctype.h> |
| 30 |
#include <inttypes.h> |
| 31 |
|
| 32 |
#include "qemu_socket.h" |
| 33 |
|
| 34 |
//#define DEBUG_NBD
|
| 35 |
|
| 36 |
#ifdef DEBUG_NBD
|
| 37 |
#define TRACE(msg, ...) do { \ |
| 38 |
LOG(msg, ## __VA_ARGS__); \ |
| 39 |
} while(0) |
| 40 |
#else
|
| 41 |
#define TRACE(msg, ...) \
|
| 42 |
do { } while (0) |
| 43 |
#endif
|
| 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 |
|
| 50 |
/* This is all part of the "official" NBD API */
|
| 51 |
|
| 52 |
#define NBD_REQUEST_MAGIC 0x25609513 |
| 53 |
#define NBD_REPLY_MAGIC 0x67446698 |
| 54 |
|
| 55 |
#define NBD_SET_SOCK _IO(0xab, 0) |
| 56 |
#define NBD_SET_BLKSIZE _IO(0xab, 1) |
| 57 |
#define NBD_SET_SIZE _IO(0xab, 2) |
| 58 |
#define NBD_DO_IT _IO(0xab, 3) |
| 59 |
#define NBD_CLEAR_SOCK _IO(0xab, 4) |
| 60 |
#define NBD_CLEAR_QUE _IO(0xab, 5) |
| 61 |
#define NBD_PRINT_DEBUG _IO(0xab, 6) |
| 62 |
#define NBD_SET_SIZE_BLOCKS _IO(0xab, 7) |
| 63 |
#define NBD_DISCONNECT _IO(0xab, 8) |
| 64 |
|
| 65 |
/* That's all folks */
|
| 66 |
|
| 67 |
#define read_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, true) |
| 68 |
#define write_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, false) |
| 69 |
|
| 70 |
size_t nbd_wr_sync(int fd, void *buffer, size_t size, bool do_read) |
| 71 |
{
|
| 72 |
size_t offset = 0;
|
| 73 |
|
| 74 |
while (offset < size) {
|
| 75 |
ssize_t len; |
| 76 |
|
| 77 |
if (do_read) {
|
| 78 |
len = recv(fd, buffer + offset, size - offset, 0);
|
| 79 |
} else {
|
| 80 |
len = send(fd, buffer + offset, size - offset, 0);
|
| 81 |
} |
| 82 |
|
| 83 |
if (len == -1) |
| 84 |
errno = socket_error(); |
| 85 |
|
| 86 |
/* recoverable error */
|
| 87 |
if (len == -1 && (errno == EAGAIN || errno == EINTR)) { |
| 88 |
continue;
|
| 89 |
} |
| 90 |
|
| 91 |
/* eof */
|
| 92 |
if (len == 0) { |
| 93 |
break;
|
| 94 |
} |
| 95 |
|
| 96 |
/* unrecoverable error */
|
| 97 |
if (len == -1) { |
| 98 |
return 0; |
| 99 |
} |
| 100 |
|
| 101 |
offset += len; |
| 102 |
} |
| 103 |
|
| 104 |
return offset;
|
| 105 |
} |
| 106 |
|
| 107 |
int tcp_socket_outgoing(const char *address, uint16_t port) |
| 108 |
{
|
| 109 |
int s;
|
| 110 |
struct in_addr in;
|
| 111 |
struct sockaddr_in addr;
|
| 112 |
|
| 113 |
s = socket(PF_INET, SOCK_STREAM, 0);
|
| 114 |
if (s == -1) { |
| 115 |
return -1; |
| 116 |
} |
| 117 |
|
| 118 |
if (inet_aton(address, &in) == 0) { |
| 119 |
struct hostent *ent;
|
| 120 |
|
| 121 |
ent = gethostbyname(address); |
| 122 |
if (ent == NULL) { |
| 123 |
goto error;
|
| 124 |
} |
| 125 |
|
| 126 |
memcpy(&in, ent->h_addr, sizeof(in));
|
| 127 |
} |
| 128 |
|
| 129 |
addr.sin_family = AF_INET; |
| 130 |
addr.sin_port = htons(port); |
| 131 |
memcpy(&addr.sin_addr.s_addr, &in, sizeof(in));
|
| 132 |
|
| 133 |
if (connect(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) { |
| 134 |
goto error;
|
| 135 |
} |
| 136 |
|
| 137 |
return s;
|
| 138 |
error:
|
| 139 |
closesocket(s); |
| 140 |
return -1; |
| 141 |
} |
| 142 |
|
| 143 |
int tcp_socket_incoming(const char *address, uint16_t port) |
| 144 |
{
|
| 145 |
int s;
|
| 146 |
struct in_addr in;
|
| 147 |
struct sockaddr_in addr;
|
| 148 |
int opt;
|
| 149 |
|
| 150 |
s = socket(PF_INET, SOCK_STREAM, 0);
|
| 151 |
if (s == -1) { |
| 152 |
return -1; |
| 153 |
} |
| 154 |
|
| 155 |
if (inet_aton(address, &in) == 0) { |
| 156 |
struct hostent *ent;
|
| 157 |
|
| 158 |
ent = gethostbyname(address); |
| 159 |
if (ent == NULL) { |
| 160 |
goto error;
|
| 161 |
} |
| 162 |
|
| 163 |
memcpy(&in, ent->h_addr, sizeof(in));
|
| 164 |
} |
| 165 |
|
| 166 |
addr.sin_family = AF_INET; |
| 167 |
addr.sin_port = htons(port); |
| 168 |
memcpy(&addr.sin_addr.s_addr, &in, sizeof(in));
|
| 169 |
|
| 170 |
opt = 1;
|
| 171 |
if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR,
|
| 172 |
(const void *) &opt, sizeof(opt)) == -1) { |
| 173 |
goto error;
|
| 174 |
} |
| 175 |
|
| 176 |
if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) { |
| 177 |
goto error;
|
| 178 |
} |
| 179 |
|
| 180 |
if (listen(s, 128) == -1) { |
| 181 |
goto error;
|
| 182 |
} |
| 183 |
|
| 184 |
return s;
|
| 185 |
error:
|
| 186 |
closesocket(s); |
| 187 |
return -1; |
| 188 |
} |
| 189 |
|
| 190 |
#ifndef _WIN32
|
| 191 |
int unix_socket_incoming(const char *path) |
| 192 |
{
|
| 193 |
int s;
|
| 194 |
struct sockaddr_un addr;
|
| 195 |
|
| 196 |
s = socket(PF_UNIX, SOCK_STREAM, 0);
|
| 197 |
if (s == -1) { |
| 198 |
return -1; |
| 199 |
} |
| 200 |
|
| 201 |
memset(&addr, 0, sizeof(addr)); |
| 202 |
addr.sun_family = AF_UNIX; |
| 203 |
pstrcpy(addr.sun_path, sizeof(addr.sun_path), path);
|
| 204 |
|
| 205 |
if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) { |
| 206 |
goto error;
|
| 207 |
} |
| 208 |
|
| 209 |
if (listen(s, 128) == -1) { |
| 210 |
goto error;
|
| 211 |
} |
| 212 |
|
| 213 |
return s;
|
| 214 |
error:
|
| 215 |
closesocket(s); |
| 216 |
return -1; |
| 217 |
} |
| 218 |
|
| 219 |
int unix_socket_outgoing(const char *path) |
| 220 |
{
|
| 221 |
int s;
|
| 222 |
struct sockaddr_un addr;
|
| 223 |
|
| 224 |
s = socket(PF_UNIX, SOCK_STREAM, 0);
|
| 225 |
if (s == -1) { |
| 226 |
return -1; |
| 227 |
} |
| 228 |
|
| 229 |
memset(&addr, 0, sizeof(addr)); |
| 230 |
addr.sun_family = AF_UNIX; |
| 231 |
pstrcpy(addr.sun_path, sizeof(addr.sun_path), path);
|
| 232 |
|
| 233 |
if (connect(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) { |
| 234 |
goto error;
|
| 235 |
} |
| 236 |
|
| 237 |
return s;
|
| 238 |
error:
|
| 239 |
closesocket(s); |
| 240 |
return -1; |
| 241 |
} |
| 242 |
#else
|
| 243 |
int unix_socket_incoming(const char *path) |
| 244 |
{
|
| 245 |
errno = ENOTSUP; |
| 246 |
return -1; |
| 247 |
} |
| 248 |
|
| 249 |
int unix_socket_outgoing(const char *path) |
| 250 |
{
|
| 251 |
errno = ENOTSUP; |
| 252 |
return -1; |
| 253 |
} |
| 254 |
#endif
|
| 255 |
|
| 256 |
|
| 257 |
/* Basic flow
|
| 258 |
|
| 259 |
Server Client
|
| 260 |
|
| 261 |
Negotiate
|
| 262 |
Request
|
| 263 |
Response
|
| 264 |
Request
|
| 265 |
Response
|
| 266 |
...
|
| 267 |
...
|
| 268 |
Request (type == 2)
|
| 269 |
*/
|
| 270 |
|
| 271 |
int nbd_negotiate(int csock, off_t size) |
| 272 |
{
|
| 273 |
char buf[8 + 8 + 8 + 128]; |
| 274 |
|
| 275 |
/* Negotiate
|
| 276 |
[ 0 .. 7] passwd ("NBDMAGIC")
|
| 277 |
[ 8 .. 15] magic (0x00420281861253)
|
| 278 |
[16 .. 23] size
|
| 279 |
[24 .. 151] reserved (0)
|
| 280 |
*/
|
| 281 |
|
| 282 |
TRACE("Beginning negotiation.");
|
| 283 |
memcpy(buf, "NBDMAGIC", 8); |
| 284 |
cpu_to_be64w((uint64_t*)(buf + 8), 0x00420281861253LL); |
| 285 |
cpu_to_be64w((uint64_t*)(buf + 16), size);
|
| 286 |
memset(buf + 24, 0, 128); |
| 287 |
|
| 288 |
if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
| 289 |
LOG("write failed");
|
| 290 |
errno = EINVAL; |
| 291 |
return -1; |
| 292 |
} |
| 293 |
|
| 294 |
TRACE("Negotation succeeded.");
|
| 295 |
|
| 296 |
return 0; |
| 297 |
} |
| 298 |
|
| 299 |
int nbd_receive_negotiate(int csock, off_t *size, size_t *blocksize) |
| 300 |
{
|
| 301 |
char buf[8 + 8 + 8 + 128]; |
| 302 |
uint64_t magic; |
| 303 |
|
| 304 |
TRACE("Receiving negotation.");
|
| 305 |
|
| 306 |
if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
| 307 |
LOG("read failed");
|
| 308 |
errno = EINVAL; |
| 309 |
return -1; |
| 310 |
} |
| 311 |
|
| 312 |
magic = be64_to_cpup((uint64_t*)(buf + 8));
|
| 313 |
*size = be64_to_cpup((uint64_t*)(buf + 16));
|
| 314 |
*blocksize = 1024;
|
| 315 |
|
| 316 |
TRACE("Magic is %c%c%c%c%c%c%c%c",
|
| 317 |
qemu_isprint(buf[0]) ? buf[0] : '.', |
| 318 |
qemu_isprint(buf[1]) ? buf[1] : '.', |
| 319 |
qemu_isprint(buf[2]) ? buf[2] : '.', |
| 320 |
qemu_isprint(buf[3]) ? buf[3] : '.', |
| 321 |
qemu_isprint(buf[4]) ? buf[4] : '.', |
| 322 |
qemu_isprint(buf[5]) ? buf[5] : '.', |
| 323 |
qemu_isprint(buf[6]) ? buf[6] : '.', |
| 324 |
qemu_isprint(buf[7]) ? buf[7] : '.'); |
| 325 |
TRACE("Magic is 0x%" PRIx64, magic);
|
| 326 |
TRACE("Size is %" PRIu64, *size);
|
| 327 |
|
| 328 |
if (memcmp(buf, "NBDMAGIC", 8) != 0) { |
| 329 |
LOG("Invalid magic received");
|
| 330 |
errno = EINVAL; |
| 331 |
return -1; |
| 332 |
} |
| 333 |
|
| 334 |
TRACE("Checking magic");
|
| 335 |
|
| 336 |
if (magic != 0x00420281861253LL) { |
| 337 |
LOG("Bad magic received");
|
| 338 |
errno = EINVAL; |
| 339 |
return -1; |
| 340 |
} |
| 341 |
return 0; |
| 342 |
} |
| 343 |
|
| 344 |
#ifndef _WIN32
|
| 345 |
int nbd_init(int fd, int csock, off_t size, size_t blocksize) |
| 346 |
{
|
| 347 |
TRACE("Setting block size to %lu", (unsigned long)blocksize); |
| 348 |
|
| 349 |
if (ioctl(fd, NBD_SET_BLKSIZE, blocksize) == -1) { |
| 350 |
int serrno = errno;
|
| 351 |
LOG("Failed setting NBD block size");
|
| 352 |
errno = serrno; |
| 353 |
return -1; |
| 354 |
} |
| 355 |
|
| 356 |
TRACE("Setting size to %zd block(s)", (size_t)(size / blocksize));
|
| 357 |
|
| 358 |
if (ioctl(fd, NBD_SET_SIZE_BLOCKS, size / blocksize) == -1) { |
| 359 |
int serrno = errno;
|
| 360 |
LOG("Failed setting size (in blocks)");
|
| 361 |
errno = serrno; |
| 362 |
return -1; |
| 363 |
} |
| 364 |
|
| 365 |
TRACE("Clearing NBD socket");
|
| 366 |
|
| 367 |
if (ioctl(fd, NBD_CLEAR_SOCK) == -1) { |
| 368 |
int serrno = errno;
|
| 369 |
LOG("Failed clearing NBD socket");
|
| 370 |
errno = serrno; |
| 371 |
return -1; |
| 372 |
} |
| 373 |
|
| 374 |
TRACE("Setting NBD socket");
|
| 375 |
|
| 376 |
if (ioctl(fd, NBD_SET_SOCK, csock) == -1) { |
| 377 |
int serrno = errno;
|
| 378 |
LOG("Failed to set NBD socket");
|
| 379 |
errno = serrno; |
| 380 |
return -1; |
| 381 |
} |
| 382 |
|
| 383 |
TRACE("Negotiation ended");
|
| 384 |
|
| 385 |
return 0; |
| 386 |
} |
| 387 |
|
| 388 |
int nbd_disconnect(int fd) |
| 389 |
{
|
| 390 |
ioctl(fd, NBD_CLEAR_QUE); |
| 391 |
ioctl(fd, NBD_DISCONNECT); |
| 392 |
ioctl(fd, NBD_CLEAR_SOCK); |
| 393 |
return 0; |
| 394 |
} |
| 395 |
|
| 396 |
int nbd_client(int fd) |
| 397 |
{
|
| 398 |
int ret;
|
| 399 |
int serrno;
|
| 400 |
|
| 401 |
TRACE("Doing NBD loop");
|
| 402 |
|
| 403 |
ret = ioctl(fd, NBD_DO_IT); |
| 404 |
serrno = errno; |
| 405 |
|
| 406 |
TRACE("NBD loop returned %d: %s", ret, strerror(serrno));
|
| 407 |
|
| 408 |
TRACE("Clearing NBD queue");
|
| 409 |
ioctl(fd, NBD_CLEAR_QUE); |
| 410 |
|
| 411 |
TRACE("Clearing NBD socket");
|
| 412 |
ioctl(fd, NBD_CLEAR_SOCK); |
| 413 |
|
| 414 |
errno = serrno; |
| 415 |
return ret;
|
| 416 |
} |
| 417 |
#else
|
| 418 |
int nbd_init(int fd, int csock, off_t size, size_t blocksize) |
| 419 |
{
|
| 420 |
errno = ENOTSUP; |
| 421 |
return -1; |
| 422 |
} |
| 423 |
|
| 424 |
int nbd_disconnect(int fd) |
| 425 |
{
|
| 426 |
errno = ENOTSUP; |
| 427 |
return -1; |
| 428 |
} |
| 429 |
|
| 430 |
int nbd_client(int fd) |
| 431 |
{
|
| 432 |
errno = ENOTSUP; |
| 433 |
return -1; |
| 434 |
} |
| 435 |
#endif
|
| 436 |
|
| 437 |
int nbd_send_request(int csock, struct nbd_request *request) |
| 438 |
{
|
| 439 |
uint8_t buf[4 + 4 + 8 + 8 + 4]; |
| 440 |
|
| 441 |
cpu_to_be32w((uint32_t*)buf, NBD_REQUEST_MAGIC); |
| 442 |
cpu_to_be32w((uint32_t*)(buf + 4), request->type);
|
| 443 |
cpu_to_be64w((uint64_t*)(buf + 8), request->handle);
|
| 444 |
cpu_to_be64w((uint64_t*)(buf + 16), request->from);
|
| 445 |
cpu_to_be32w((uint32_t*)(buf + 24), request->len);
|
| 446 |
|
| 447 |
TRACE("Sending request to client");
|
| 448 |
|
| 449 |
if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
| 450 |
LOG("writing to socket failed");
|
| 451 |
errno = EINVAL; |
| 452 |
return -1; |
| 453 |
} |
| 454 |
return 0; |
| 455 |
} |
| 456 |
|
| 457 |
|
| 458 |
static int nbd_receive_request(int csock, struct nbd_request *request) |
| 459 |
{
|
| 460 |
uint8_t buf[4 + 4 + 8 + 8 + 4]; |
| 461 |
uint32_t magic; |
| 462 |
|
| 463 |
if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
| 464 |
LOG("read failed");
|
| 465 |
errno = EINVAL; |
| 466 |
return -1; |
| 467 |
} |
| 468 |
|
| 469 |
/* Request
|
| 470 |
[ 0 .. 3] magic (NBD_REQUEST_MAGIC)
|
| 471 |
[ 4 .. 7] type (0 == READ, 1 == WRITE)
|
| 472 |
[ 8 .. 15] handle
|
| 473 |
[16 .. 23] from
|
| 474 |
[24 .. 27] len
|
| 475 |
*/
|
| 476 |
|
| 477 |
magic = be32_to_cpup((uint32_t*)buf); |
| 478 |
request->type = be32_to_cpup((uint32_t*)(buf + 4));
|
| 479 |
request->handle = be64_to_cpup((uint64_t*)(buf + 8));
|
| 480 |
request->from = be64_to_cpup((uint64_t*)(buf + 16));
|
| 481 |
request->len = be32_to_cpup((uint32_t*)(buf + 24));
|
| 482 |
|
| 483 |
TRACE("Got request: "
|
| 484 |
"{ magic = 0x%x, .type = %d, from = %" PRIu64" , len = %u }", |
| 485 |
magic, request->type, request->from, request->len); |
| 486 |
|
| 487 |
if (magic != NBD_REQUEST_MAGIC) {
|
| 488 |
LOG("invalid magic (got 0x%x)", magic);
|
| 489 |
errno = EINVAL; |
| 490 |
return -1; |
| 491 |
} |
| 492 |
return 0; |
| 493 |
} |
| 494 |
|
| 495 |
int nbd_receive_reply(int csock, struct nbd_reply *reply) |
| 496 |
{
|
| 497 |
uint8_t buf[4 + 4 + 8]; |
| 498 |
uint32_t magic; |
| 499 |
|
| 500 |
memset(buf, 0xAA, sizeof(buf)); |
| 501 |
|
| 502 |
if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
| 503 |
LOG("read failed");
|
| 504 |
errno = EINVAL; |
| 505 |
return -1; |
| 506 |
} |
| 507 |
|
| 508 |
/* Reply
|
| 509 |
[ 0 .. 3] magic (NBD_REPLY_MAGIC)
|
| 510 |
[ 4 .. 7] error (0 == no error)
|
| 511 |
[ 7 .. 15] handle
|
| 512 |
*/
|
| 513 |
|
| 514 |
magic = be32_to_cpup((uint32_t*)buf); |
| 515 |
reply->error = be32_to_cpup((uint32_t*)(buf + 4));
|
| 516 |
reply->handle = be64_to_cpup((uint64_t*)(buf + 8));
|
| 517 |
|
| 518 |
TRACE("Got reply: "
|
| 519 |
"{ magic = 0x%x, .error = %d, handle = %" PRIu64" }", |
| 520 |
magic, reply->error, reply->handle); |
| 521 |
|
| 522 |
if (magic != NBD_REPLY_MAGIC) {
|
| 523 |
LOG("invalid magic (got 0x%x)", magic);
|
| 524 |
errno = EINVAL; |
| 525 |
return -1; |
| 526 |
} |
| 527 |
return 0; |
| 528 |
} |
| 529 |
|
| 530 |
static int nbd_send_reply(int csock, struct nbd_reply *reply) |
| 531 |
{
|
| 532 |
uint8_t buf[4 + 4 + 8]; |
| 533 |
|
| 534 |
/* Reply
|
| 535 |
[ 0 .. 3] magic (NBD_REPLY_MAGIC)
|
| 536 |
[ 4 .. 7] error (0 == no error)
|
| 537 |
[ 7 .. 15] handle
|
| 538 |
*/
|
| 539 |
cpu_to_be32w((uint32_t*)buf, NBD_REPLY_MAGIC); |
| 540 |
cpu_to_be32w((uint32_t*)(buf + 4), reply->error);
|
| 541 |
cpu_to_be64w((uint64_t*)(buf + 8), reply->handle);
|
| 542 |
|
| 543 |
TRACE("Sending response to client");
|
| 544 |
|
| 545 |
if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
| 546 |
LOG("writing to socket failed");
|
| 547 |
errno = EINVAL; |
| 548 |
return -1; |
| 549 |
} |
| 550 |
return 0; |
| 551 |
} |
| 552 |
|
| 553 |
int nbd_trip(BlockDriverState *bs, int csock, off_t size, uint64_t dev_offset, |
| 554 |
off_t *offset, bool readonly, uint8_t *data, int data_size) |
| 555 |
{
|
| 556 |
struct nbd_request request;
|
| 557 |
struct nbd_reply reply;
|
| 558 |
|
| 559 |
TRACE("Reading request.");
|
| 560 |
|
| 561 |
if (nbd_receive_request(csock, &request) == -1) |
| 562 |
return -1; |
| 563 |
|
| 564 |
if (request.len > data_size) {
|
| 565 |
LOG("len (%u) is larger than max len (%u)",
|
| 566 |
request.len, data_size); |
| 567 |
errno = EINVAL; |
| 568 |
return -1; |
| 569 |
} |
| 570 |
|
| 571 |
if ((request.from + request.len) < request.from) {
|
| 572 |
LOG("integer overflow detected! "
|
| 573 |
"you're probably being attacked");
|
| 574 |
errno = EINVAL; |
| 575 |
return -1; |
| 576 |
} |
| 577 |
|
| 578 |
if ((request.from + request.len) > size) {
|
| 579 |
LOG("From: %" PRIu64 ", Len: %u, Size: %" PRIu64 |
| 580 |
", Offset: %" PRIu64 "\n", |
| 581 |
request.from, request.len, (uint64_t)size, dev_offset); |
| 582 |
LOG("requested operation past EOF--bad client?");
|
| 583 |
errno = EINVAL; |
| 584 |
return -1; |
| 585 |
} |
| 586 |
|
| 587 |
TRACE("Decoding type");
|
| 588 |
|
| 589 |
reply.handle = request.handle; |
| 590 |
reply.error = 0;
|
| 591 |
|
| 592 |
switch (request.type) {
|
| 593 |
case NBD_CMD_READ:
|
| 594 |
TRACE("Request type is READ");
|
| 595 |
|
| 596 |
if (bdrv_read(bs, (request.from + dev_offset) / 512, data, |
| 597 |
request.len / 512) == -1) { |
| 598 |
LOG("reading from file failed");
|
| 599 |
errno = EINVAL; |
| 600 |
return -1; |
| 601 |
} |
| 602 |
*offset += request.len; |
| 603 |
|
| 604 |
TRACE("Read %u byte(s)", request.len);
|
| 605 |
|
| 606 |
if (nbd_send_reply(csock, &reply) == -1) |
| 607 |
return -1; |
| 608 |
|
| 609 |
TRACE("Sending data to client");
|
| 610 |
|
| 611 |
if (write_sync(csock, data, request.len) != request.len) {
|
| 612 |
LOG("writing to socket failed");
|
| 613 |
errno = EINVAL; |
| 614 |
return -1; |
| 615 |
} |
| 616 |
break;
|
| 617 |
case NBD_CMD_WRITE:
|
| 618 |
TRACE("Request type is WRITE");
|
| 619 |
|
| 620 |
TRACE("Reading %u byte(s)", request.len);
|
| 621 |
|
| 622 |
if (read_sync(csock, data, request.len) != request.len) {
|
| 623 |
LOG("reading from socket failed");
|
| 624 |
errno = EINVAL; |
| 625 |
return -1; |
| 626 |
} |
| 627 |
|
| 628 |
if (readonly) {
|
| 629 |
TRACE("Server is read-only, return error");
|
| 630 |
reply.error = 1;
|
| 631 |
} else {
|
| 632 |
TRACE("Writing to device");
|
| 633 |
|
| 634 |
if (bdrv_write(bs, (request.from + dev_offset) / 512, |
| 635 |
data, request.len / 512) == -1) { |
| 636 |
LOG("writing to file failed");
|
| 637 |
errno = EINVAL; |
| 638 |
return -1; |
| 639 |
} |
| 640 |
|
| 641 |
*offset += request.len; |
| 642 |
} |
| 643 |
|
| 644 |
if (nbd_send_reply(csock, &reply) == -1) |
| 645 |
return -1; |
| 646 |
break;
|
| 647 |
case NBD_CMD_DISC:
|
| 648 |
TRACE("Request type is DISCONNECT");
|
| 649 |
errno = 0;
|
| 650 |
return 1; |
| 651 |
default:
|
| 652 |
LOG("invalid request type (%u) received", request.type);
|
| 653 |
errno = EINVAL; |
| 654 |
return -1; |
| 655 |
} |
| 656 |
|
| 657 |
TRACE("Request/Reply complete");
|
| 658 |
|
| 659 |
return 0; |
| 660 |
} |