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/*
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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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#ifdef __sun__
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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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#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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|
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/* This is all part of the "official" NBD API */
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|
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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) |
57 |
#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) |
60 |
#define NBD_CLEAR_QUE _IO(0xab, 5) |
61 |
#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) |
66 |
|
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/* That's all folks */
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#define read_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, true) |
70 |
#define write_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, false) |
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|
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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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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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|
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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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/* unrecoverable error */
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if (len == -1) { |
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return 0; |
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} |
102 |
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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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} |
119 |
|
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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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} |
127 |
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memcpy(&in, ent->h_addr, sizeof(in));
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} |
130 |
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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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} |
138 |
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return s;
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error:
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closesocket(s); |
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return -1; |
143 |
} |
144 |
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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; |
155 |
} |
156 |
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if (inet_aton(address, &in) == 0) { |
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struct hostent *ent;
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ent = gethostbyname(address); |
161 |
if (ent == NULL) { |
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goto error;
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} |
164 |
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memcpy(&in, ent->h_addr, sizeof(in));
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} |
167 |
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addr.sin_family = AF_INET; |
169 |
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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} |
177 |
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if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) == -1) { |
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goto error;
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} |
181 |
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if (listen(s, 128) == -1) { |
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goto error;
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} |
185 |
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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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} |
202 |
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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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} |
210 |
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if (listen(s, 128) == -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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} |
220 |
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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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} |
230 |
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memset(&addr, 0, sizeof(addr)); |
232 |
addr.sun_family = AF_UNIX; |
233 |
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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} |
238 |
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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; |
249 |
} |
250 |
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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]; |
276 |
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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); |
289 |
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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; |
293 |
return -1; |
294 |
} |
295 |
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TRACE("Negotation succeeded.");
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return 0; |
299 |
} |
300 |
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int nbd_receive_negotiate(int csock, const char *name, uint32_t *flags, |
302 |
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; |
307 |
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TRACE("Receiving negotation.");
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309 |
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if (read_sync(csock, buf, 8) != 8) { |
311 |
LOG("read failed");
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errno = EINVAL; |
313 |
return -1; |
314 |
} |
315 |
|
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buf[8] = '\0'; |
317 |
if (strlen(buf) == 0) { |
318 |
LOG("server connection closed");
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errno = EINVAL; |
320 |
return -1; |
321 |
} |
322 |
|
323 |
TRACE("Magic is %c%c%c%c%c%c%c%c",
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324 |
qemu_isprint(buf[0]) ? buf[0] : '.', |
325 |
qemu_isprint(buf[1]) ? buf[1] : '.', |
326 |
qemu_isprint(buf[2]) ? buf[2] : '.', |
327 |
qemu_isprint(buf[3]) ? buf[3] : '.', |
328 |
qemu_isprint(buf[4]) ? buf[4] : '.', |
329 |
qemu_isprint(buf[5]) ? buf[5] : '.', |
330 |
qemu_isprint(buf[6]) ? buf[6] : '.', |
331 |
qemu_isprint(buf[7]) ? buf[7] : '.'); |
332 |
|
333 |
if (memcmp(buf, "NBDMAGIC", 8) != 0) { |
334 |
LOG("Invalid magic received");
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335 |
errno = EINVAL; |
336 |
return -1; |
337 |
} |
338 |
|
339 |
if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { |
340 |
LOG("read failed");
|
341 |
errno = EINVAL; |
342 |
return -1; |
343 |
} |
344 |
magic = be64_to_cpu(magic); |
345 |
TRACE("Magic is 0x%" PRIx64, magic);
|
346 |
|
347 |
if (name) {
|
348 |
uint32_t reserved = 0;
|
349 |
uint32_t opt; |
350 |
uint32_t namesize; |
351 |
|
352 |
TRACE("Checking magic (opts_magic)");
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353 |
if (magic != 0x49484156454F5054LL) { |
354 |
LOG("Bad magic received");
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355 |
errno = EINVAL; |
356 |
return -1; |
357 |
} |
358 |
if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { |
359 |
LOG("flags read failed");
|
360 |
errno = EINVAL; |
361 |
return -1; |
362 |
} |
363 |
*flags = be16_to_cpu(tmp) << 16;
|
364 |
/* reserved for future use */
|
365 |
if (write_sync(csock, &reserved, sizeof(reserved)) != |
366 |
sizeof(reserved)) {
|
367 |
LOG("write failed (reserved)");
|
368 |
errno = EINVAL; |
369 |
return -1; |
370 |
} |
371 |
/* write the export name */
|
372 |
magic = cpu_to_be64(magic); |
373 |
if (write_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { |
374 |
LOG("write failed (magic)");
|
375 |
errno = EINVAL; |
376 |
return -1; |
377 |
} |
378 |
opt = cpu_to_be32(NBD_OPT_EXPORT_NAME); |
379 |
if (write_sync(csock, &opt, sizeof(opt)) != sizeof(opt)) { |
380 |
LOG("write failed (opt)");
|
381 |
errno = EINVAL; |
382 |
return -1; |
383 |
} |
384 |
namesize = cpu_to_be32(strlen(name)); |
385 |
if (write_sync(csock, &namesize, sizeof(namesize)) != |
386 |
sizeof(namesize)) {
|
387 |
LOG("write failed (namesize)");
|
388 |
errno = EINVAL; |
389 |
return -1; |
390 |
} |
391 |
if (write_sync(csock, (char*)name, strlen(name)) != strlen(name)) { |
392 |
LOG("write failed (name)");
|
393 |
errno = EINVAL; |
394 |
return -1; |
395 |
} |
396 |
} else {
|
397 |
TRACE("Checking magic (cli_magic)");
|
398 |
|
399 |
if (magic != 0x00420281861253LL) { |
400 |
LOG("Bad magic received");
|
401 |
errno = EINVAL; |
402 |
return -1; |
403 |
} |
404 |
} |
405 |
|
406 |
if (read_sync(csock, &s, sizeof(s)) != sizeof(s)) { |
407 |
LOG("read failed");
|
408 |
errno = EINVAL; |
409 |
return -1; |
410 |
} |
411 |
*size = be64_to_cpu(s); |
412 |
*blocksize = 1024;
|
413 |
TRACE("Size is %" PRIu64, *size);
|
414 |
|
415 |
if (!name) {
|
416 |
if (read_sync(csock, flags, sizeof(*flags)) != sizeof(*flags)) { |
417 |
LOG("read failed (flags)");
|
418 |
errno = EINVAL; |
419 |
return -1; |
420 |
} |
421 |
*flags = be32_to_cpup(flags); |
422 |
} else {
|
423 |
if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { |
424 |
LOG("read failed (tmp)");
|
425 |
errno = EINVAL; |
426 |
return -1; |
427 |
} |
428 |
*flags |= be32_to_cpu(tmp); |
429 |
} |
430 |
if (read_sync(csock, &buf, 124) != 124) { |
431 |
LOG("read failed (buf)");
|
432 |
errno = EINVAL; |
433 |
return -1; |
434 |
} |
435 |
return 0; |
436 |
} |
437 |
|
438 |
#ifndef _WIN32
|
439 |
int nbd_init(int fd, int csock, off_t size, size_t blocksize) |
440 |
{ |
441 |
TRACE("Setting block size to %lu", (unsigned long)blocksize); |
442 |
|
443 |
if (ioctl(fd, NBD_SET_BLKSIZE, blocksize) == -1) { |
444 |
int serrno = errno;
|
445 |
LOG("Failed setting NBD block size");
|
446 |
errno = serrno; |
447 |
return -1; |
448 |
} |
449 |
|
450 |
TRACE("Setting size to %zd block(s)", (size_t)(size / blocksize));
|
451 |
|
452 |
if (ioctl(fd, NBD_SET_SIZE_BLOCKS, size / blocksize) == -1) { |
453 |
int serrno = errno;
|
454 |
LOG("Failed setting size (in blocks)");
|
455 |
errno = serrno; |
456 |
return -1; |
457 |
} |
458 |
|
459 |
TRACE("Clearing NBD socket");
|
460 |
|
461 |
if (ioctl(fd, NBD_CLEAR_SOCK) == -1) { |
462 |
int serrno = errno;
|
463 |
LOG("Failed clearing NBD socket");
|
464 |
errno = serrno; |
465 |
return -1; |
466 |
} |
467 |
|
468 |
TRACE("Setting NBD socket");
|
469 |
|
470 |
if (ioctl(fd, NBD_SET_SOCK, csock) == -1) { |
471 |
int serrno = errno;
|
472 |
LOG("Failed to set NBD socket");
|
473 |
errno = serrno; |
474 |
return -1; |
475 |
} |
476 |
|
477 |
TRACE("Negotiation ended");
|
478 |
|
479 |
return 0; |
480 |
} |
481 |
|
482 |
int nbd_disconnect(int fd) |
483 |
{ |
484 |
ioctl(fd, NBD_CLEAR_QUE); |
485 |
ioctl(fd, NBD_DISCONNECT); |
486 |
ioctl(fd, NBD_CLEAR_SOCK); |
487 |
return 0; |
488 |
} |
489 |
|
490 |
int nbd_client(int fd, int csock) |
491 |
{ |
492 |
int ret;
|
493 |
int serrno;
|
494 |
|
495 |
TRACE("Doing NBD loop");
|
496 |
|
497 |
ret = ioctl(fd, NBD_DO_IT); |
498 |
serrno = errno; |
499 |
|
500 |
TRACE("NBD loop returned %d: %s", ret, strerror(serrno));
|
501 |
|
502 |
TRACE("Clearing NBD queue");
|
503 |
ioctl(fd, NBD_CLEAR_QUE); |
504 |
|
505 |
TRACE("Clearing NBD socket");
|
506 |
ioctl(fd, NBD_CLEAR_SOCK); |
507 |
|
508 |
errno = serrno; |
509 |
return ret;
|
510 |
} |
511 |
#else
|
512 |
int nbd_init(int fd, int csock, off_t size, size_t blocksize) |
513 |
{ |
514 |
errno = ENOTSUP; |
515 |
return -1; |
516 |
} |
517 |
|
518 |
int nbd_disconnect(int fd) |
519 |
{ |
520 |
errno = ENOTSUP; |
521 |
return -1; |
522 |
} |
523 |
|
524 |
int nbd_client(int fd, int csock) |
525 |
{ |
526 |
errno = ENOTSUP; |
527 |
return -1; |
528 |
} |
529 |
#endif
|
530 |
|
531 |
int nbd_send_request(int csock, struct nbd_request *request) |
532 |
{ |
533 |
uint8_t buf[4 + 4 + 8 + 8 + 4]; |
534 |
|
535 |
cpu_to_be32w((uint32_t*)buf, NBD_REQUEST_MAGIC); |
536 |
cpu_to_be32w((uint32_t*)(buf + 4), request->type);
|
537 |
cpu_to_be64w((uint64_t*)(buf + 8), request->handle);
|
538 |
cpu_to_be64w((uint64_t*)(buf + 16), request->from);
|
539 |
cpu_to_be32w((uint32_t*)(buf + 24), request->len);
|
540 |
|
541 |
TRACE("Sending request to client");
|
542 |
|
543 |
if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
544 |
LOG("writing to socket failed");
|
545 |
errno = EINVAL; |
546 |
return -1; |
547 |
} |
548 |
return 0; |
549 |
} |
550 |
|
551 |
|
552 |
static int nbd_receive_request(int csock, struct nbd_request *request) |
553 |
{ |
554 |
uint8_t buf[4 + 4 + 8 + 8 + 4]; |
555 |
uint32_t magic; |
556 |
|
557 |
if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
558 |
LOG("read failed");
|
559 |
errno = EINVAL; |
560 |
return -1; |
561 |
} |
562 |
|
563 |
/* Request
|
564 |
[ 0 .. 3] magic (NBD_REQUEST_MAGIC)
|
565 |
[ 4 .. 7] type (0 == READ, 1 == WRITE)
|
566 |
[ 8 .. 15] handle
|
567 |
[16 .. 23] from
|
568 |
[24 .. 27] len
|
569 |
*/
|
570 |
|
571 |
magic = be32_to_cpup((uint32_t*)buf); |
572 |
request->type = be32_to_cpup((uint32_t*)(buf + 4));
|
573 |
request->handle = be64_to_cpup((uint64_t*)(buf + 8));
|
574 |
request->from = be64_to_cpup((uint64_t*)(buf + 16));
|
575 |
request->len = be32_to_cpup((uint32_t*)(buf + 24));
|
576 |
|
577 |
TRACE("Got request: "
|
578 |
"{ magic = 0x%x, .type = %d, from = %" PRIu64" , len = %u }", |
579 |
magic, request->type, request->from, request->len); |
580 |
|
581 |
if (magic != NBD_REQUEST_MAGIC) {
|
582 |
LOG("invalid magic (got 0x%x)", magic);
|
583 |
errno = EINVAL; |
584 |
return -1; |
585 |
} |
586 |
return 0; |
587 |
} |
588 |
|
589 |
int nbd_receive_reply(int csock, struct nbd_reply *reply) |
590 |
{ |
591 |
uint8_t buf[4 + 4 + 8]; |
592 |
uint32_t magic; |
593 |
|
594 |
memset(buf, 0xAA, sizeof(buf)); |
595 |
|
596 |
if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
597 |
LOG("read failed");
|
598 |
errno = EINVAL; |
599 |
return -1; |
600 |
} |
601 |
|
602 |
/* Reply
|
603 |
[ 0 .. 3] magic (NBD_REPLY_MAGIC)
|
604 |
[ 4 .. 7] error (0 == no error)
|
605 |
[ 7 .. 15] handle
|
606 |
*/
|
607 |
|
608 |
magic = be32_to_cpup((uint32_t*)buf); |
609 |
reply->error = be32_to_cpup((uint32_t*)(buf + 4));
|
610 |
reply->handle = be64_to_cpup((uint64_t*)(buf + 8));
|
611 |
|
612 |
TRACE("Got reply: "
|
613 |
"{ magic = 0x%x, .error = %d, handle = %" PRIu64" }", |
614 |
magic, reply->error, reply->handle); |
615 |
|
616 |
if (magic != NBD_REPLY_MAGIC) {
|
617 |
LOG("invalid magic (got 0x%x)", magic);
|
618 |
errno = EINVAL; |
619 |
return -1; |
620 |
} |
621 |
return 0; |
622 |
} |
623 |
|
624 |
static int nbd_send_reply(int csock, struct nbd_reply *reply) |
625 |
{ |
626 |
uint8_t buf[4 + 4 + 8]; |
627 |
|
628 |
/* Reply
|
629 |
[ 0 .. 3] magic (NBD_REPLY_MAGIC)
|
630 |
[ 4 .. 7] error (0 == no error)
|
631 |
[ 7 .. 15] handle
|
632 |
*/
|
633 |
cpu_to_be32w((uint32_t*)buf, NBD_REPLY_MAGIC); |
634 |
cpu_to_be32w((uint32_t*)(buf + 4), reply->error);
|
635 |
cpu_to_be64w((uint64_t*)(buf + 8), reply->handle);
|
636 |
|
637 |
TRACE("Sending response to client");
|
638 |
|
639 |
if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
640 |
LOG("writing to socket failed");
|
641 |
errno = EINVAL; |
642 |
return -1; |
643 |
} |
644 |
return 0; |
645 |
} |
646 |
|
647 |
int nbd_trip(BlockDriverState *bs, int csock, off_t size, uint64_t dev_offset, |
648 |
off_t *offset, bool readonly, uint8_t *data, int data_size) |
649 |
{ |
650 |
struct nbd_request request;
|
651 |
struct nbd_reply reply;
|
652 |
|
653 |
TRACE("Reading request.");
|
654 |
|
655 |
if (nbd_receive_request(csock, &request) == -1) |
656 |
return -1; |
657 |
|
658 |
if (request.len > data_size) {
|
659 |
LOG("len (%u) is larger than max len (%u)",
|
660 |
request.len, data_size); |
661 |
errno = EINVAL; |
662 |
return -1; |
663 |
} |
664 |
|
665 |
if ((request.from + request.len) < request.from) {
|
666 |
LOG("integer overflow detected! "
|
667 |
"you're probably being attacked");
|
668 |
errno = EINVAL; |
669 |
return -1; |
670 |
} |
671 |
|
672 |
if ((request.from + request.len) > size) {
|
673 |
LOG("From: %" PRIu64 ", Len: %u, Size: %" PRIu64 |
674 |
", Offset: %" PRIu64 "\n", |
675 |
request.from, request.len, (uint64_t)size, dev_offset); |
676 |
LOG("requested operation past EOF--bad client?");
|
677 |
errno = EINVAL; |
678 |
return -1; |
679 |
} |
680 |
|
681 |
TRACE("Decoding type");
|
682 |
|
683 |
reply.handle = request.handle; |
684 |
reply.error = 0;
|
685 |
|
686 |
switch (request.type) {
|
687 |
case NBD_CMD_READ:
|
688 |
TRACE("Request type is READ");
|
689 |
|
690 |
if (bdrv_read(bs, (request.from + dev_offset) / 512, data, |
691 |
request.len / 512) == -1) { |
692 |
LOG("reading from file failed");
|
693 |
errno = EINVAL; |
694 |
return -1; |
695 |
} |
696 |
*offset += request.len; |
697 |
|
698 |
TRACE("Read %u byte(s)", request.len);
|
699 |
|
700 |
if (nbd_send_reply(csock, &reply) == -1) |
701 |
return -1; |
702 |
|
703 |
TRACE("Sending data to client");
|
704 |
|
705 |
if (write_sync(csock, data, request.len) != request.len) {
|
706 |
LOG("writing to socket failed");
|
707 |
errno = EINVAL; |
708 |
return -1; |
709 |
} |
710 |
break;
|
711 |
case NBD_CMD_WRITE:
|
712 |
TRACE("Request type is WRITE");
|
713 |
|
714 |
TRACE("Reading %u byte(s)", request.len);
|
715 |
|
716 |
if (read_sync(csock, data, request.len) != request.len) {
|
717 |
LOG("reading from socket failed");
|
718 |
errno = EINVAL; |
719 |
return -1; |
720 |
} |
721 |
|
722 |
if (readonly) {
|
723 |
TRACE("Server is read-only, return error");
|
724 |
reply.error = 1;
|
725 |
} else {
|
726 |
TRACE("Writing to device");
|
727 |
|
728 |
if (bdrv_write(bs, (request.from + dev_offset) / 512, |
729 |
data, request.len / 512) == -1) { |
730 |
LOG("writing to file failed");
|
731 |
errno = EINVAL; |
732 |
return -1; |
733 |
} |
734 |
|
735 |
*offset += request.len; |
736 |
} |
737 |
|
738 |
if (nbd_send_reply(csock, &reply) == -1) |
739 |
return -1; |
740 |
break;
|
741 |
case NBD_CMD_DISC:
|
742 |
TRACE("Request type is DISCONNECT");
|
743 |
errno = 0;
|
744 |
return 1; |
745 |
default:
|
746 |
LOG("invalid request type (%u) received", request.type);
|
747 |
errno = EINVAL; |
748 |
return -1; |
749 |
} |
750 |
|
751 |
TRACE("Request/Reply complete");
|
752 |
|
753 |
return 0; |
754 |
} |