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/*
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* Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
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*
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* Network Block Device
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; under version 2 of the License.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, see <http://www.gnu.org/licenses/>.
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*/
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#include "nbd.h" |
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#include <errno.h> |
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#include <string.h> |
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#ifndef _WIN32
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#include <sys/ioctl.h> |
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#endif
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#if defined(__sun__) || defined(__HAIKU__)
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#include <sys/ioccom.h> |
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#endif
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#include <ctype.h> |
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#include <inttypes.h> |
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|
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#include "qemu_socket.h" |
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|
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//#define DEBUG_NBD
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|
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#ifdef DEBUG_NBD
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#define TRACE(msg, ...) do { \ |
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LOG(msg, ## __VA_ARGS__); \ |
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} while(0) |
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#else
|
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#define TRACE(msg, ...) \
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do { } while (0) |
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#endif
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|
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#define LOG(msg, ...) do { \ |
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fprintf(stderr, "%s:%s():L%d: " msg "\n", \ |
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__FILE__, __FUNCTION__, __LINE__, ## __VA_ARGS__); \ |
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} while(0) |
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/* This is all part of the "official" NBD API */
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|
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#define NBD_REPLY_SIZE (4 + 4 + 8) |
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#define NBD_REQUEST_MAGIC 0x25609513 |
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#define NBD_REPLY_MAGIC 0x67446698 |
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|
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#define NBD_SET_SOCK _IO(0xab, 0) |
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#define NBD_SET_BLKSIZE _IO(0xab, 1) |
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#define NBD_SET_SIZE _IO(0xab, 2) |
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#define NBD_DO_IT _IO(0xab, 3) |
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#define NBD_CLEAR_SOCK _IO(0xab, 4) |
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#define NBD_CLEAR_QUE _IO(0xab, 5) |
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#define NBD_PRINT_DEBUG _IO(0xab, 6) |
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#define NBD_SET_SIZE_BLOCKS _IO(0xab, 7) |
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#define NBD_DISCONNECT _IO(0xab, 8) |
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|
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#define NBD_OPT_EXPORT_NAME (1 << 0) |
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|
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/* That's all folks */
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|
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#define read_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, true) |
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#define write_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, false) |
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size_t nbd_wr_sync(int fd, void *buffer, size_t size, bool do_read) |
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{ |
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size_t offset = 0;
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|
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while (offset < size) {
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ssize_t len; |
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if (do_read) {
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len = recv(fd, buffer + offset, size - offset, 0);
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} else {
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len = send(fd, buffer + offset, size - offset, 0);
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} |
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|
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if (len == -1) |
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errno = socket_error(); |
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|
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/* recoverable error */
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if (len == -1 && (errno == EAGAIN || errno == EINTR)) { |
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continue;
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} |
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/* eof */
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if (len == 0) { |
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break;
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} |
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|
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/* unrecoverable error */
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if (len == -1) { |
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return 0; |
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} |
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offset += len; |
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} |
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return offset;
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} |
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int tcp_socket_outgoing(const char *address, uint16_t port) |
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{ |
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int s;
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struct in_addr in;
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struct sockaddr_in addr;
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s = socket(PF_INET, SOCK_STREAM, 0);
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if (s == -1) { |
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return -1; |
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} |
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if (inet_aton(address, &in) == 0) { |
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struct hostent *ent;
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ent = gethostbyname(address); |
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if (ent == NULL) { |
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goto error;
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} |
128 |
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memcpy(&in, ent->h_addr, sizeof(in));
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} |
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addr.sin_family = AF_INET; |
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addr.sin_port = htons(port); |
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memcpy(&addr.sin_addr.s_addr, &in, sizeof(in));
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if (connect(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) { |
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goto error;
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} |
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return s;
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error:
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closesocket(s); |
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return -1; |
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} |
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int tcp_socket_incoming(const char *address, uint16_t port) |
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{ |
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int s;
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struct in_addr in;
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struct sockaddr_in addr;
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int opt;
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s = socket(PF_INET, SOCK_STREAM, 0);
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if (s == -1) { |
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return -1; |
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} |
157 |
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if (inet_aton(address, &in) == 0) { |
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struct hostent *ent;
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ent = gethostbyname(address); |
162 |
if (ent == NULL) { |
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goto error;
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} |
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memcpy(&in, ent->h_addr, sizeof(in));
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} |
168 |
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addr.sin_family = AF_INET; |
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addr.sin_port = htons(port); |
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memcpy(&addr.sin_addr.s_addr, &in, sizeof(in));
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opt = 1;
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if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR,
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(const void *) &opt, sizeof(opt)) == -1) { |
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goto error;
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} |
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if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) { |
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goto error;
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} |
182 |
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if (listen(s, 128) == -1) { |
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goto error;
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} |
186 |
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return s;
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error:
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closesocket(s); |
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return -1; |
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} |
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#ifndef _WIN32
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int unix_socket_incoming(const char *path) |
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{ |
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int s;
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struct sockaddr_un addr;
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s = socket(PF_UNIX, SOCK_STREAM, 0);
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if (s == -1) { |
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return -1; |
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} |
203 |
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memset(&addr, 0, sizeof(addr)); |
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addr.sun_family = AF_UNIX; |
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pstrcpy(addr.sun_path, sizeof(addr.sun_path), path);
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if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) { |
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goto error;
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} |
211 |
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if (listen(s, 128) == -1) { |
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goto error;
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} |
215 |
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return s;
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error:
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closesocket(s); |
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return -1; |
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} |
221 |
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int unix_socket_outgoing(const char *path) |
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{ |
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int s;
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struct sockaddr_un addr;
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s = socket(PF_UNIX, SOCK_STREAM, 0);
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if (s == -1) { |
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return -1; |
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} |
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memset(&addr, 0, sizeof(addr)); |
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addr.sun_family = AF_UNIX; |
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pstrcpy(addr.sun_path, sizeof(addr.sun_path), path);
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if (connect(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) { |
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goto error;
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} |
239 |
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return s;
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error:
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closesocket(s); |
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return -1; |
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} |
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#else
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int unix_socket_incoming(const char *path) |
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{ |
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errno = ENOTSUP; |
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return -1; |
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} |
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int unix_socket_outgoing(const char *path) |
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{ |
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errno = ENOTSUP; |
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return -1; |
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} |
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#endif
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/* Basic flow
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Server Client
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Negotiate
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Request
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Response
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Request
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Response
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...
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...
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Request (type == 2)
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*/
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int nbd_negotiate(int csock, off_t size) |
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{ |
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char buf[8 + 8 + 8 + 128]; |
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/* Negotiate
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[ 0 .. 7] passwd ("NBDMAGIC")
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[ 8 .. 15] magic (0x00420281861253)
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[16 .. 23] size
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[24 .. 151] reserved (0)
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*/
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TRACE("Beginning negotiation.");
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memcpy(buf, "NBDMAGIC", 8); |
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cpu_to_be64w((uint64_t*)(buf + 8), 0x00420281861253LL); |
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cpu_to_be64w((uint64_t*)(buf + 16), size);
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memset(buf + 24, 0, 128); |
290 |
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if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
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LOG("write failed");
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errno = EINVAL; |
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return -1; |
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} |
296 |
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TRACE("Negotation succeeded.");
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return 0; |
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} |
301 |
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int nbd_receive_negotiate(int csock, const char *name, uint32_t *flags, |
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off_t *size, size_t *blocksize) |
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{ |
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char buf[256]; |
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uint64_t magic, s; |
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uint16_t tmp; |
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TRACE("Receiving negotation.");
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if (read_sync(csock, buf, 8) != 8) { |
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LOG("read failed");
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errno = EINVAL; |
314 |
return -1; |
315 |
} |
316 |
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buf[8] = '\0'; |
318 |
if (strlen(buf) == 0) { |
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LOG("server connection closed");
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errno = EINVAL; |
321 |
return -1; |
322 |
} |
323 |
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TRACE("Magic is %c%c%c%c%c%c%c%c",
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qemu_isprint(buf[0]) ? buf[0] : '.', |
326 |
qemu_isprint(buf[1]) ? buf[1] : '.', |
327 |
qemu_isprint(buf[2]) ? buf[2] : '.', |
328 |
qemu_isprint(buf[3]) ? buf[3] : '.', |
329 |
qemu_isprint(buf[4]) ? buf[4] : '.', |
330 |
qemu_isprint(buf[5]) ? buf[5] : '.', |
331 |
qemu_isprint(buf[6]) ? buf[6] : '.', |
332 |
qemu_isprint(buf[7]) ? buf[7] : '.'); |
333 |
|
334 |
if (memcmp(buf, "NBDMAGIC", 8) != 0) { |
335 |
LOG("Invalid magic received");
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336 |
errno = EINVAL; |
337 |
return -1; |
338 |
} |
339 |
|
340 |
if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { |
341 |
LOG("read failed");
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342 |
errno = EINVAL; |
343 |
return -1; |
344 |
} |
345 |
magic = be64_to_cpu(magic); |
346 |
TRACE("Magic is 0x%" PRIx64, magic);
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347 |
|
348 |
if (name) {
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349 |
uint32_t reserved = 0;
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350 |
uint32_t opt; |
351 |
uint32_t namesize; |
352 |
|
353 |
TRACE("Checking magic (opts_magic)");
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354 |
if (magic != 0x49484156454F5054LL) { |
355 |
LOG("Bad magic received");
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356 |
errno = EINVAL; |
357 |
return -1; |
358 |
} |
359 |
if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { |
360 |
LOG("flags read failed");
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361 |
errno = EINVAL; |
362 |
return -1; |
363 |
} |
364 |
*flags = be16_to_cpu(tmp) << 16;
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365 |
/* reserved for future use */
|
366 |
if (write_sync(csock, &reserved, sizeof(reserved)) != |
367 |
sizeof(reserved)) {
|
368 |
LOG("write failed (reserved)");
|
369 |
errno = EINVAL; |
370 |
return -1; |
371 |
} |
372 |
/* write the export name */
|
373 |
magic = cpu_to_be64(magic); |
374 |
if (write_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { |
375 |
LOG("write failed (magic)");
|
376 |
errno = EINVAL; |
377 |
return -1; |
378 |
} |
379 |
opt = cpu_to_be32(NBD_OPT_EXPORT_NAME); |
380 |
if (write_sync(csock, &opt, sizeof(opt)) != sizeof(opt)) { |
381 |
LOG("write failed (opt)");
|
382 |
errno = EINVAL; |
383 |
return -1; |
384 |
} |
385 |
namesize = cpu_to_be32(strlen(name)); |
386 |
if (write_sync(csock, &namesize, sizeof(namesize)) != |
387 |
sizeof(namesize)) {
|
388 |
LOG("write failed (namesize)");
|
389 |
errno = EINVAL; |
390 |
return -1; |
391 |
} |
392 |
if (write_sync(csock, (char*)name, strlen(name)) != strlen(name)) { |
393 |
LOG("write failed (name)");
|
394 |
errno = EINVAL; |
395 |
return -1; |
396 |
} |
397 |
} else {
|
398 |
TRACE("Checking magic (cli_magic)");
|
399 |
|
400 |
if (magic != 0x00420281861253LL) { |
401 |
LOG("Bad magic received");
|
402 |
errno = EINVAL; |
403 |
return -1; |
404 |
} |
405 |
} |
406 |
|
407 |
if (read_sync(csock, &s, sizeof(s)) != sizeof(s)) { |
408 |
LOG("read failed");
|
409 |
errno = EINVAL; |
410 |
return -1; |
411 |
} |
412 |
*size = be64_to_cpu(s); |
413 |
*blocksize = 1024;
|
414 |
TRACE("Size is %" PRIu64, *size);
|
415 |
|
416 |
if (!name) {
|
417 |
if (read_sync(csock, flags, sizeof(*flags)) != sizeof(*flags)) { |
418 |
LOG("read failed (flags)");
|
419 |
errno = EINVAL; |
420 |
return -1; |
421 |
} |
422 |
*flags = be32_to_cpup(flags); |
423 |
} else {
|
424 |
if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { |
425 |
LOG("read failed (tmp)");
|
426 |
errno = EINVAL; |
427 |
return -1; |
428 |
} |
429 |
*flags |= be32_to_cpu(tmp); |
430 |
} |
431 |
if (read_sync(csock, &buf, 124) != 124) { |
432 |
LOG("read failed (buf)");
|
433 |
errno = EINVAL; |
434 |
return -1; |
435 |
} |
436 |
return 0; |
437 |
} |
438 |
|
439 |
#ifndef _WIN32
|
440 |
int nbd_init(int fd, int csock, off_t size, size_t blocksize) |
441 |
{ |
442 |
TRACE("Setting block size to %lu", (unsigned long)blocksize); |
443 |
|
444 |
if (ioctl(fd, NBD_SET_BLKSIZE, blocksize) == -1) { |
445 |
int serrno = errno;
|
446 |
LOG("Failed setting NBD block size");
|
447 |
errno = serrno; |
448 |
return -1; |
449 |
} |
450 |
|
451 |
TRACE("Setting size to %zd block(s)", (size_t)(size / blocksize));
|
452 |
|
453 |
if (ioctl(fd, NBD_SET_SIZE_BLOCKS, size / blocksize) == -1) { |
454 |
int serrno = errno;
|
455 |
LOG("Failed setting size (in blocks)");
|
456 |
errno = serrno; |
457 |
return -1; |
458 |
} |
459 |
|
460 |
TRACE("Clearing NBD socket");
|
461 |
|
462 |
if (ioctl(fd, NBD_CLEAR_SOCK) == -1) { |
463 |
int serrno = errno;
|
464 |
LOG("Failed clearing NBD socket");
|
465 |
errno = serrno; |
466 |
return -1; |
467 |
} |
468 |
|
469 |
TRACE("Setting NBD socket");
|
470 |
|
471 |
if (ioctl(fd, NBD_SET_SOCK, csock) == -1) { |
472 |
int serrno = errno;
|
473 |
LOG("Failed to set NBD socket");
|
474 |
errno = serrno; |
475 |
return -1; |
476 |
} |
477 |
|
478 |
TRACE("Negotiation ended");
|
479 |
|
480 |
return 0; |
481 |
} |
482 |
|
483 |
int nbd_disconnect(int fd) |
484 |
{ |
485 |
ioctl(fd, NBD_CLEAR_QUE); |
486 |
ioctl(fd, NBD_DISCONNECT); |
487 |
ioctl(fd, NBD_CLEAR_SOCK); |
488 |
return 0; |
489 |
} |
490 |
|
491 |
int nbd_client(int fd) |
492 |
{ |
493 |
int ret;
|
494 |
int serrno;
|
495 |
|
496 |
TRACE("Doing NBD loop");
|
497 |
|
498 |
ret = ioctl(fd, NBD_DO_IT); |
499 |
serrno = errno; |
500 |
|
501 |
TRACE("NBD loop returned %d: %s", ret, strerror(serrno));
|
502 |
|
503 |
TRACE("Clearing NBD queue");
|
504 |
ioctl(fd, NBD_CLEAR_QUE); |
505 |
|
506 |
TRACE("Clearing NBD socket");
|
507 |
ioctl(fd, NBD_CLEAR_SOCK); |
508 |
|
509 |
errno = serrno; |
510 |
return ret;
|
511 |
} |
512 |
#else
|
513 |
int nbd_init(int fd, int csock, off_t size, size_t blocksize) |
514 |
{ |
515 |
errno = ENOTSUP; |
516 |
return -1; |
517 |
} |
518 |
|
519 |
int nbd_disconnect(int fd) |
520 |
{ |
521 |
errno = ENOTSUP; |
522 |
return -1; |
523 |
} |
524 |
|
525 |
int nbd_client(int fd) |
526 |
{ |
527 |
errno = ENOTSUP; |
528 |
return -1; |
529 |
} |
530 |
#endif
|
531 |
|
532 |
int nbd_send_request(int csock, struct nbd_request *request) |
533 |
{ |
534 |
uint8_t buf[4 + 4 + 8 + 8 + 4]; |
535 |
|
536 |
cpu_to_be32w((uint32_t*)buf, NBD_REQUEST_MAGIC); |
537 |
cpu_to_be32w((uint32_t*)(buf + 4), request->type);
|
538 |
cpu_to_be64w((uint64_t*)(buf + 8), request->handle);
|
539 |
cpu_to_be64w((uint64_t*)(buf + 16), request->from);
|
540 |
cpu_to_be32w((uint32_t*)(buf + 24), request->len);
|
541 |
|
542 |
TRACE("Sending request to client: "
|
543 |
"{ .from = %" PRIu64", .len = %u, .handle = %" PRIu64", .type=%i}", |
544 |
request->from, request->len, request->handle, request->type); |
545 |
|
546 |
if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
547 |
LOG("writing to socket failed");
|
548 |
errno = EINVAL; |
549 |
return -1; |
550 |
} |
551 |
return 0; |
552 |
} |
553 |
|
554 |
static int nbd_receive_request(int csock, struct nbd_request *request) |
555 |
{ |
556 |
uint8_t buf[4 + 4 + 8 + 8 + 4]; |
557 |
uint32_t magic; |
558 |
|
559 |
if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
560 |
LOG("read failed");
|
561 |
errno = EINVAL; |
562 |
return -1; |
563 |
} |
564 |
|
565 |
/* Request
|
566 |
[ 0 .. 3] magic (NBD_REQUEST_MAGIC)
|
567 |
[ 4 .. 7] type (0 == READ, 1 == WRITE)
|
568 |
[ 8 .. 15] handle
|
569 |
[16 .. 23] from
|
570 |
[24 .. 27] len
|
571 |
*/
|
572 |
|
573 |
magic = be32_to_cpup((uint32_t*)buf); |
574 |
request->type = be32_to_cpup((uint32_t*)(buf + 4));
|
575 |
request->handle = be64_to_cpup((uint64_t*)(buf + 8));
|
576 |
request->from = be64_to_cpup((uint64_t*)(buf + 16));
|
577 |
request->len = be32_to_cpup((uint32_t*)(buf + 24));
|
578 |
|
579 |
TRACE("Got request: "
|
580 |
"{ magic = 0x%x, .type = %d, from = %" PRIu64" , len = %u }", |
581 |
magic, request->type, request->from, request->len); |
582 |
|
583 |
if (magic != NBD_REQUEST_MAGIC) {
|
584 |
LOG("invalid magic (got 0x%x)", magic);
|
585 |
errno = EINVAL; |
586 |
return -1; |
587 |
} |
588 |
return 0; |
589 |
} |
590 |
|
591 |
int nbd_receive_reply(int csock, struct nbd_reply *reply) |
592 |
{ |
593 |
uint8_t buf[NBD_REPLY_SIZE]; |
594 |
uint32_t magic; |
595 |
|
596 |
memset(buf, 0xAA, sizeof(buf)); |
597 |
|
598 |
if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
599 |
LOG("read failed");
|
600 |
errno = EINVAL; |
601 |
return -1; |
602 |
} |
603 |
|
604 |
/* Reply
|
605 |
[ 0 .. 3] magic (NBD_REPLY_MAGIC)
|
606 |
[ 4 .. 7] error (0 == no error)
|
607 |
[ 7 .. 15] handle
|
608 |
*/
|
609 |
|
610 |
magic = be32_to_cpup((uint32_t*)buf); |
611 |
reply->error = be32_to_cpup((uint32_t*)(buf + 4));
|
612 |
reply->handle = be64_to_cpup((uint64_t*)(buf + 8));
|
613 |
|
614 |
TRACE("Got reply: "
|
615 |
"{ magic = 0x%x, .error = %d, handle = %" PRIu64" }", |
616 |
magic, reply->error, reply->handle); |
617 |
|
618 |
if (magic != NBD_REPLY_MAGIC) {
|
619 |
LOG("invalid magic (got 0x%x)", magic);
|
620 |
errno = EINVAL; |
621 |
return -1; |
622 |
} |
623 |
return 0; |
624 |
} |
625 |
|
626 |
static int nbd_send_reply(int csock, struct nbd_reply *reply) |
627 |
{ |
628 |
uint8_t buf[4 + 4 + 8]; |
629 |
|
630 |
/* Reply
|
631 |
[ 0 .. 3] magic (NBD_REPLY_MAGIC)
|
632 |
[ 4 .. 7] error (0 == no error)
|
633 |
[ 7 .. 15] handle
|
634 |
*/
|
635 |
cpu_to_be32w((uint32_t*)buf, NBD_REPLY_MAGIC); |
636 |
cpu_to_be32w((uint32_t*)(buf + 4), reply->error);
|
637 |
cpu_to_be64w((uint64_t*)(buf + 8), reply->handle);
|
638 |
|
639 |
TRACE("Sending response to client");
|
640 |
|
641 |
if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
642 |
LOG("writing to socket failed");
|
643 |
errno = EINVAL; |
644 |
return -1; |
645 |
} |
646 |
return 0; |
647 |
} |
648 |
|
649 |
int nbd_trip(BlockDriverState *bs, int csock, off_t size, uint64_t dev_offset, |
650 |
off_t *offset, bool readonly, uint8_t *data, int data_size) |
651 |
{ |
652 |
struct nbd_request request;
|
653 |
struct nbd_reply reply;
|
654 |
|
655 |
TRACE("Reading request.");
|
656 |
|
657 |
if (nbd_receive_request(csock, &request) == -1) |
658 |
return -1; |
659 |
|
660 |
if (request.len + NBD_REPLY_SIZE > data_size) {
|
661 |
LOG("len (%u) is larger than max len (%u)",
|
662 |
request.len + NBD_REPLY_SIZE, data_size); |
663 |
errno = EINVAL; |
664 |
return -1; |
665 |
} |
666 |
|
667 |
if ((request.from + request.len) < request.from) {
|
668 |
LOG("integer overflow detected! "
|
669 |
"you're probably being attacked");
|
670 |
errno = EINVAL; |
671 |
return -1; |
672 |
} |
673 |
|
674 |
if ((request.from + request.len) > size) {
|
675 |
LOG("From: %" PRIu64 ", Len: %u, Size: %" PRIu64 |
676 |
", Offset: %" PRIu64 "\n", |
677 |
request.from, request.len, (uint64_t)size, dev_offset); |
678 |
LOG("requested operation past EOF--bad client?");
|
679 |
errno = EINVAL; |
680 |
return -1; |
681 |
} |
682 |
|
683 |
TRACE("Decoding type");
|
684 |
|
685 |
reply.handle = request.handle; |
686 |
reply.error = 0;
|
687 |
|
688 |
switch (request.type) {
|
689 |
case NBD_CMD_READ:
|
690 |
TRACE("Request type is READ");
|
691 |
|
692 |
if (bdrv_read(bs, (request.from + dev_offset) / 512, |
693 |
data + NBD_REPLY_SIZE, |
694 |
request.len / 512) == -1) { |
695 |
LOG("reading from file failed");
|
696 |
errno = EINVAL; |
697 |
return -1; |
698 |
} |
699 |
*offset += request.len; |
700 |
|
701 |
TRACE("Read %u byte(s)", request.len);
|
702 |
|
703 |
/* Reply
|
704 |
[ 0 .. 3] magic (NBD_REPLY_MAGIC)
|
705 |
[ 4 .. 7] error (0 == no error)
|
706 |
[ 7 .. 15] handle
|
707 |
*/
|
708 |
|
709 |
cpu_to_be32w((uint32_t*)data, NBD_REPLY_MAGIC); |
710 |
cpu_to_be32w((uint32_t*)(data + 4), reply.error);
|
711 |
cpu_to_be64w((uint64_t*)(data + 8), reply.handle);
|
712 |
|
713 |
TRACE("Sending data to client");
|
714 |
|
715 |
if (write_sync(csock, data,
|
716 |
request.len + NBD_REPLY_SIZE) != |
717 |
request.len + NBD_REPLY_SIZE) { |
718 |
LOG("writing to socket failed");
|
719 |
errno = EINVAL; |
720 |
return -1; |
721 |
} |
722 |
break;
|
723 |
case NBD_CMD_WRITE:
|
724 |
TRACE("Request type is WRITE");
|
725 |
|
726 |
TRACE("Reading %u byte(s)", request.len);
|
727 |
|
728 |
if (read_sync(csock, data, request.len) != request.len) {
|
729 |
LOG("reading from socket failed");
|
730 |
errno = EINVAL; |
731 |
return -1; |
732 |
} |
733 |
|
734 |
if (readonly) {
|
735 |
TRACE("Server is read-only, return error");
|
736 |
reply.error = 1;
|
737 |
} else {
|
738 |
TRACE("Writing to device");
|
739 |
|
740 |
if (bdrv_write(bs, (request.from + dev_offset) / 512, |
741 |
data, request.len / 512) == -1) { |
742 |
LOG("writing to file failed");
|
743 |
errno = EINVAL; |
744 |
return -1; |
745 |
} |
746 |
|
747 |
*offset += request.len; |
748 |
} |
749 |
|
750 |
if (nbd_send_reply(csock, &reply) == -1) |
751 |
return -1; |
752 |
break;
|
753 |
case NBD_CMD_DISC:
|
754 |
TRACE("Request type is DISCONNECT");
|
755 |
errno = 0;
|
756 |
return 1; |
757 |
default:
|
758 |
LOG("invalid request type (%u) received", request.type);
|
759 |
errno = EINVAL; |
760 |
return -1; |
761 |
} |
762 |
|
763 |
TRACE("Request/Reply complete");
|
764 |
|
765 |
return 0; |
766 |
} |