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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 "block.h" |
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#include "block_int.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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#ifdef __linux__
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#include <linux/fs.h> |
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#endif
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#include "qemu_socket.h" |
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#include "qemu-queue.h" |
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//#define DEBUG_NBD
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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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#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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#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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#define NBD_SET_TIMEOUT _IO(0xab, 9) |
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#define NBD_SET_FLAGS _IO(0xab, 10) |
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#define NBD_OPT_EXPORT_NAME (1 << 0) |
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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) |
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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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if (qemu_in_coroutine()) {
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if (do_read) {
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return qemu_co_recv(fd, buffer, size);
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} else {
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return qemu_co_send(fd, buffer, size);
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} |
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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 = qemu_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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/* 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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/* 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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static void combine_addr(char *buf, size_t len, const char* address, |
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uint16_t port) |
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{ |
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/* If the address-part contains a colon, it's an IPv6 IP so needs [] */
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if (strstr(address, ":")) { |
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snprintf(buf, len, "[%s]:%u", address, port);
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} else {
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snprintf(buf, len, "%s:%u", address, port);
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} |
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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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char address_and_port[128]; |
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combine_addr(address_and_port, 128, address, port);
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return tcp_socket_outgoing_spec(address_and_port);
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} |
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int tcp_socket_outgoing_spec(const char *address_and_port) |
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{ |
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return inet_connect(address_and_port, SOCK_STREAM);
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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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char address_and_port[128]; |
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combine_addr(address_and_port, 128, address, port);
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return tcp_socket_incoming_spec(address_and_port);
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} |
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int tcp_socket_incoming_spec(const char *address_and_port) |
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{ |
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char *ostr = NULL; |
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int olen = 0; |
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return inet_listen(address_and_port, ostr, olen, SOCK_STREAM, 0); |
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} |
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int unix_socket_incoming(const char *path) |
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{ |
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char *ostr = NULL; |
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int olen = 0; |
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return unix_listen(path, ostr, olen);
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} |
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int unix_socket_outgoing(const char *path) |
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{ |
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return unix_connect(path);
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} |
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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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static int nbd_send_negotiate(int csock, off_t size, uint32_t flags) |
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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 .. 27] flags
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[28 .. 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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cpu_to_be32w((uint32_t*)(buf + 24),
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flags | NBD_FLAG_HAS_FLAGS | NBD_FLAG_SEND_TRIM | |
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NBD_FLAG_SEND_FLUSH | NBD_FLAG_SEND_FUA); |
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memset(buf + 28, 0, 124); |
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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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} |
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TRACE("Negotiation succeeded.");
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return 0; |
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} |
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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 negotiation.");
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if (read_sync(csock, buf, 8) != 8) { |
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LOG("read failed");
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errno = EINVAL; |
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return -1; |
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} |
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buf[8] = '\0'; |
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if (strlen(buf) == 0) { |
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LOG("server connection closed");
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errno = EINVAL; |
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return -1; |
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} |
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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] : '.', |
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qemu_isprint(buf[1]) ? buf[1] : '.', |
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qemu_isprint(buf[2]) ? buf[2] : '.', |
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qemu_isprint(buf[3]) ? buf[3] : '.', |
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qemu_isprint(buf[4]) ? buf[4] : '.', |
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qemu_isprint(buf[5]) ? buf[5] : '.', |
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qemu_isprint(buf[6]) ? buf[6] : '.', |
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qemu_isprint(buf[7]) ? buf[7] : '.'); |
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if (memcmp(buf, "NBDMAGIC", 8) != 0) { |
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LOG("Invalid magic received");
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errno = EINVAL; |
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return -1; |
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} |
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if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { |
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LOG("read failed");
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errno = EINVAL; |
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return -1; |
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} |
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magic = be64_to_cpu(magic); |
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TRACE("Magic is 0x%" PRIx64, magic);
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if (name) {
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uint32_t reserved = 0;
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uint32_t opt; |
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uint32_t namesize; |
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TRACE("Checking magic (opts_magic)");
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if (magic != 0x49484156454F5054LL) { |
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LOG("Bad magic received");
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errno = EINVAL; |
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return -1; |
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} |
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if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { |
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LOG("flags read failed");
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errno = EINVAL; |
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return -1; |
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} |
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*flags = be16_to_cpu(tmp) << 16;
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/* reserved for future use */
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if (write_sync(csock, &reserved, sizeof(reserved)) != |
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sizeof(reserved)) {
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LOG("write failed (reserved)");
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errno = EINVAL; |
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return -1; |
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} |
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/* write the export name */
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magic = cpu_to_be64(magic); |
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if (write_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { |
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LOG("write failed (magic)");
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errno = EINVAL; |
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return -1; |
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} |
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opt = cpu_to_be32(NBD_OPT_EXPORT_NAME); |
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if (write_sync(csock, &opt, sizeof(opt)) != sizeof(opt)) { |
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LOG("write failed (opt)");
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errno = EINVAL; |
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return -1; |
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} |
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namesize = cpu_to_be32(strlen(name)); |
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if (write_sync(csock, &namesize, sizeof(namesize)) != |
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sizeof(namesize)) {
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LOG("write failed (namesize)");
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errno = EINVAL; |
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return -1; |
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} |
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if (write_sync(csock, (char*)name, strlen(name)) != strlen(name)) { |
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LOG("write failed (name)");
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errno = EINVAL; |
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return -1; |
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} |
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} else {
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TRACE("Checking magic (cli_magic)");
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if (magic != 0x00420281861253LL) { |
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LOG("Bad magic received");
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errno = EINVAL; |
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return -1; |
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} |
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} |
327 |
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if (read_sync(csock, &s, sizeof(s)) != sizeof(s)) { |
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LOG("read failed");
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errno = EINVAL; |
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return -1; |
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} |
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*size = be64_to_cpu(s); |
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*blocksize = 1024;
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TRACE("Size is %" PRIu64, *size);
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if (!name) {
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if (read_sync(csock, flags, sizeof(*flags)) != sizeof(*flags)) { |
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LOG("read failed (flags)");
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errno = EINVAL; |
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return -1; |
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} |
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*flags = be32_to_cpup(flags); |
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} else {
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if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { |
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LOG("read failed (tmp)");
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errno = EINVAL; |
348 |
return -1; |
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} |
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*flags |= be32_to_cpu(tmp); |
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} |
352 |
if (read_sync(csock, &buf, 124) != 124) { |
353 |
LOG("read failed (buf)");
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errno = EINVAL; |
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return -1; |
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} |
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return 0; |
358 |
} |
359 |
|
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#ifdef __linux__
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int nbd_init(int fd, int csock, uint32_t flags, off_t size, size_t blocksize) |
362 |
{ |
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TRACE("Setting NBD socket");
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364 |
|
365 |
if (ioctl(fd, NBD_SET_SOCK, csock) == -1) { |
366 |
int serrno = errno;
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367 |
LOG("Failed to set NBD socket");
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368 |
errno = serrno; |
369 |
return -1; |
370 |
} |
371 |
|
372 |
TRACE("Setting block size to %lu", (unsigned long)blocksize); |
373 |
|
374 |
if (ioctl(fd, NBD_SET_BLKSIZE, blocksize) == -1) { |
375 |
int serrno = errno;
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376 |
LOG("Failed setting NBD block size");
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377 |
errno = serrno; |
378 |
return -1; |
379 |
} |
380 |
|
381 |
TRACE("Setting size to %zd block(s)", (size_t)(size / blocksize));
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382 |
|
383 |
if (ioctl(fd, NBD_SET_SIZE_BLOCKS, size / blocksize) == -1) { |
384 |
int serrno = errno;
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385 |
LOG("Failed setting size (in blocks)");
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386 |
errno = serrno; |
387 |
return -1; |
388 |
} |
389 |
|
390 |
if (flags & NBD_FLAG_READ_ONLY) {
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391 |
int read_only = 1; |
392 |
TRACE("Setting readonly attribute");
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393 |
|
394 |
if (ioctl(fd, BLKROSET, (unsigned long) &read_only) < 0) { |
395 |
int serrno = errno;
|
396 |
LOG("Failed setting read-only attribute");
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397 |
errno = serrno; |
398 |
return -1; |
399 |
} |
400 |
} |
401 |
|
402 |
if (ioctl(fd, NBD_SET_FLAGS, flags) < 0 |
403 |
&& errno != ENOTTY) { |
404 |
int serrno = errno;
|
405 |
LOG("Failed setting flags");
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406 |
errno = serrno; |
407 |
return -1; |
408 |
} |
409 |
|
410 |
TRACE("Negotiation ended");
|
411 |
|
412 |
return 0; |
413 |
} |
414 |
|
415 |
int nbd_disconnect(int fd) |
416 |
{ |
417 |
ioctl(fd, NBD_CLEAR_QUE); |
418 |
ioctl(fd, NBD_DISCONNECT); |
419 |
ioctl(fd, NBD_CLEAR_SOCK); |
420 |
return 0; |
421 |
} |
422 |
|
423 |
int nbd_client(int fd) |
424 |
{ |
425 |
int ret;
|
426 |
int serrno;
|
427 |
|
428 |
TRACE("Doing NBD loop");
|
429 |
|
430 |
ret = ioctl(fd, NBD_DO_IT); |
431 |
if (ret == -1 && errno == EPIPE) { |
432 |
/* NBD_DO_IT normally returns EPIPE when someone has disconnected
|
433 |
* the socket via NBD_DISCONNECT. We do not want to return 1 in
|
434 |
* that case.
|
435 |
*/
|
436 |
ret = 0;
|
437 |
} |
438 |
serrno = errno; |
439 |
|
440 |
TRACE("NBD loop returned %d: %s", ret, strerror(serrno));
|
441 |
|
442 |
TRACE("Clearing NBD queue");
|
443 |
ioctl(fd, NBD_CLEAR_QUE); |
444 |
|
445 |
TRACE("Clearing NBD socket");
|
446 |
ioctl(fd, NBD_CLEAR_SOCK); |
447 |
|
448 |
errno = serrno; |
449 |
return ret;
|
450 |
} |
451 |
#else
|
452 |
int nbd_init(int fd, int csock, uint32_t flags, off_t size, size_t blocksize) |
453 |
{ |
454 |
errno = ENOTSUP; |
455 |
return -1; |
456 |
} |
457 |
|
458 |
int nbd_disconnect(int fd) |
459 |
{ |
460 |
errno = ENOTSUP; |
461 |
return -1; |
462 |
} |
463 |
|
464 |
int nbd_client(int fd) |
465 |
{ |
466 |
errno = ENOTSUP; |
467 |
return -1; |
468 |
} |
469 |
#endif
|
470 |
|
471 |
int nbd_send_request(int csock, struct nbd_request *request) |
472 |
{ |
473 |
uint8_t buf[4 + 4 + 8 + 8 + 4]; |
474 |
|
475 |
cpu_to_be32w((uint32_t*)buf, NBD_REQUEST_MAGIC); |
476 |
cpu_to_be32w((uint32_t*)(buf + 4), request->type);
|
477 |
cpu_to_be64w((uint64_t*)(buf + 8), request->handle);
|
478 |
cpu_to_be64w((uint64_t*)(buf + 16), request->from);
|
479 |
cpu_to_be32w((uint32_t*)(buf + 24), request->len);
|
480 |
|
481 |
TRACE("Sending request to client: "
|
482 |
"{ .from = %" PRIu64", .len = %u, .handle = %" PRIu64", .type=%i}", |
483 |
request->from, request->len, request->handle, request->type); |
484 |
|
485 |
if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
486 |
LOG("writing to socket failed");
|
487 |
errno = EINVAL; |
488 |
return -1; |
489 |
} |
490 |
return 0; |
491 |
} |
492 |
|
493 |
static int nbd_receive_request(int csock, struct nbd_request *request) |
494 |
{ |
495 |
uint8_t buf[4 + 4 + 8 + 8 + 4]; |
496 |
uint32_t magic; |
497 |
|
498 |
if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
499 |
LOG("read failed");
|
500 |
errno = EINVAL; |
501 |
return -1; |
502 |
} |
503 |
|
504 |
/* Request
|
505 |
[ 0 .. 3] magic (NBD_REQUEST_MAGIC)
|
506 |
[ 4 .. 7] type (0 == READ, 1 == WRITE)
|
507 |
[ 8 .. 15] handle
|
508 |
[16 .. 23] from
|
509 |
[24 .. 27] len
|
510 |
*/
|
511 |
|
512 |
magic = be32_to_cpup((uint32_t*)buf); |
513 |
request->type = be32_to_cpup((uint32_t*)(buf + 4));
|
514 |
request->handle = be64_to_cpup((uint64_t*)(buf + 8));
|
515 |
request->from = be64_to_cpup((uint64_t*)(buf + 16));
|
516 |
request->len = be32_to_cpup((uint32_t*)(buf + 24));
|
517 |
|
518 |
TRACE("Got request: "
|
519 |
"{ magic = 0x%x, .type = %d, from = %" PRIu64" , len = %u }", |
520 |
magic, request->type, request->from, request->len); |
521 |
|
522 |
if (magic != NBD_REQUEST_MAGIC) {
|
523 |
LOG("invalid magic (got 0x%x)", magic);
|
524 |
errno = EINVAL; |
525 |
return -1; |
526 |
} |
527 |
return 0; |
528 |
} |
529 |
|
530 |
int nbd_receive_reply(int csock, struct nbd_reply *reply) |
531 |
{ |
532 |
uint8_t buf[NBD_REPLY_SIZE]; |
533 |
uint32_t magic; |
534 |
|
535 |
memset(buf, 0xAA, sizeof(buf)); |
536 |
|
537 |
if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
538 |
LOG("read failed");
|
539 |
errno = EINVAL; |
540 |
return -1; |
541 |
} |
542 |
|
543 |
/* Reply
|
544 |
[ 0 .. 3] magic (NBD_REPLY_MAGIC)
|
545 |
[ 4 .. 7] error (0 == no error)
|
546 |
[ 7 .. 15] handle
|
547 |
*/
|
548 |
|
549 |
magic = be32_to_cpup((uint32_t*)buf); |
550 |
reply->error = be32_to_cpup((uint32_t*)(buf + 4));
|
551 |
reply->handle = be64_to_cpup((uint64_t*)(buf + 8));
|
552 |
|
553 |
TRACE("Got reply: "
|
554 |
"{ magic = 0x%x, .error = %d, handle = %" PRIu64" }", |
555 |
magic, reply->error, reply->handle); |
556 |
|
557 |
if (magic != NBD_REPLY_MAGIC) {
|
558 |
LOG("invalid magic (got 0x%x)", magic);
|
559 |
errno = EINVAL; |
560 |
return -1; |
561 |
} |
562 |
return 0; |
563 |
} |
564 |
|
565 |
static int nbd_send_reply(int csock, struct nbd_reply *reply) |
566 |
{ |
567 |
uint8_t buf[4 + 4 + 8]; |
568 |
|
569 |
/* Reply
|
570 |
[ 0 .. 3] magic (NBD_REPLY_MAGIC)
|
571 |
[ 4 .. 7] error (0 == no error)
|
572 |
[ 7 .. 15] handle
|
573 |
*/
|
574 |
cpu_to_be32w((uint32_t*)buf, NBD_REPLY_MAGIC); |
575 |
cpu_to_be32w((uint32_t*)(buf + 4), reply->error);
|
576 |
cpu_to_be64w((uint64_t*)(buf + 8), reply->handle);
|
577 |
|
578 |
TRACE("Sending response to client");
|
579 |
|
580 |
if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
581 |
LOG("writing to socket failed");
|
582 |
errno = EINVAL; |
583 |
return -1; |
584 |
} |
585 |
return 0; |
586 |
} |
587 |
|
588 |
typedef struct NBDRequest NBDRequest; |
589 |
|
590 |
struct NBDRequest {
|
591 |
QSIMPLEQ_ENTRY(NBDRequest) entry; |
592 |
uint8_t *data; |
593 |
}; |
594 |
|
595 |
struct NBDExport {
|
596 |
BlockDriverState *bs; |
597 |
off_t dev_offset; |
598 |
off_t size; |
599 |
uint32_t nbdflags; |
600 |
QSIMPLEQ_HEAD(, NBDRequest) requests; |
601 |
}; |
602 |
|
603 |
struct NBDClient {
|
604 |
int refcount;
|
605 |
void (*close)(NBDClient *client);
|
606 |
|
607 |
NBDExport *exp; |
608 |
int sock;
|
609 |
}; |
610 |
|
611 |
static void nbd_client_get(NBDClient *client) |
612 |
{ |
613 |
client->refcount++; |
614 |
} |
615 |
|
616 |
static void nbd_client_put(NBDClient *client) |
617 |
{ |
618 |
if (--client->refcount == 0) { |
619 |
g_free(client); |
620 |
} |
621 |
} |
622 |
|
623 |
static void nbd_client_close(NBDClient *client) |
624 |
{ |
625 |
qemu_set_fd_handler2(client->sock, NULL, NULL, NULL, NULL); |
626 |
close(client->sock); |
627 |
client->sock = -1;
|
628 |
if (client->close) {
|
629 |
client->close(client); |
630 |
} |
631 |
nbd_client_put(client); |
632 |
} |
633 |
|
634 |
static NBDRequest *nbd_request_get(NBDExport *exp)
|
635 |
{ |
636 |
NBDRequest *req; |
637 |
if (QSIMPLEQ_EMPTY(&exp->requests)) {
|
638 |
req = g_malloc0(sizeof(NBDRequest));
|
639 |
req->data = qemu_blockalign(exp->bs, NBD_BUFFER_SIZE); |
640 |
} else {
|
641 |
req = QSIMPLEQ_FIRST(&exp->requests); |
642 |
QSIMPLEQ_REMOVE_HEAD(&exp->requests, entry); |
643 |
} |
644 |
return req;
|
645 |
} |
646 |
|
647 |
static void nbd_request_put(NBDExport *exp, NBDRequest *req) |
648 |
{ |
649 |
QSIMPLEQ_INSERT_HEAD(&exp->requests, req, entry); |
650 |
} |
651 |
|
652 |
NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset, |
653 |
off_t size, uint32_t nbdflags) |
654 |
{ |
655 |
NBDExport *exp = g_malloc0(sizeof(NBDExport));
|
656 |
QSIMPLEQ_INIT(&exp->requests); |
657 |
exp->bs = bs; |
658 |
exp->dev_offset = dev_offset; |
659 |
exp->nbdflags = nbdflags; |
660 |
exp->size = size == -1 ? exp->bs->total_sectors * 512 : size; |
661 |
return exp;
|
662 |
} |
663 |
|
664 |
void nbd_export_close(NBDExport *exp)
|
665 |
{ |
666 |
while (!QSIMPLEQ_EMPTY(&exp->requests)) {
|
667 |
NBDRequest *first = QSIMPLEQ_FIRST(&exp->requests); |
668 |
QSIMPLEQ_REMOVE_HEAD(&exp->requests, entry); |
669 |
qemu_vfree(first->data); |
670 |
g_free(first); |
671 |
} |
672 |
|
673 |
bdrv_close(exp->bs); |
674 |
g_free(exp); |
675 |
} |
676 |
|
677 |
static int nbd_do_send_reply(int csock, struct nbd_reply *reply, |
678 |
uint8_t *data, int len)
|
679 |
{ |
680 |
int rc, ret;
|
681 |
|
682 |
if (!len) {
|
683 |
rc = nbd_send_reply(csock, reply); |
684 |
if (rc == -1) { |
685 |
rc = -errno; |
686 |
} |
687 |
} else {
|
688 |
socket_set_cork(csock, 1);
|
689 |
rc = nbd_send_reply(csock, reply); |
690 |
if (rc != -1) { |
691 |
ret = write_sync(csock, data, len); |
692 |
if (ret != len) {
|
693 |
errno = EIO; |
694 |
rc = -1;
|
695 |
} |
696 |
} |
697 |
if (rc == -1) { |
698 |
rc = -errno; |
699 |
} |
700 |
socket_set_cork(csock, 0);
|
701 |
} |
702 |
return rc;
|
703 |
} |
704 |
|
705 |
static int nbd_do_receive_request(int csock, struct nbd_request *request, |
706 |
uint8_t *data) |
707 |
{ |
708 |
int rc;
|
709 |
|
710 |
if (nbd_receive_request(csock, request) == -1) { |
711 |
rc = -EIO; |
712 |
goto out;
|
713 |
} |
714 |
|
715 |
if (request->len > NBD_BUFFER_SIZE) {
|
716 |
LOG("len (%u) is larger than max len (%u)",
|
717 |
request->len, NBD_BUFFER_SIZE); |
718 |
rc = -EINVAL; |
719 |
goto out;
|
720 |
} |
721 |
|
722 |
if ((request->from + request->len) < request->from) {
|
723 |
LOG("integer overflow detected! "
|
724 |
"you're probably being attacked");
|
725 |
rc = -EINVAL; |
726 |
goto out;
|
727 |
} |
728 |
|
729 |
TRACE("Decoding type");
|
730 |
|
731 |
if ((request->type & NBD_CMD_MASK_COMMAND) == NBD_CMD_WRITE) {
|
732 |
TRACE("Reading %u byte(s)", request->len);
|
733 |
|
734 |
if (read_sync(csock, data, request->len) != request->len) {
|
735 |
LOG("reading from socket failed");
|
736 |
rc = -EIO; |
737 |
goto out;
|
738 |
} |
739 |
} |
740 |
rc = 0;
|
741 |
|
742 |
out:
|
743 |
return rc;
|
744 |
} |
745 |
|
746 |
static int nbd_trip(NBDClient *client) |
747 |
{ |
748 |
NBDExport *exp = client->exp; |
749 |
NBDRequest *req = nbd_request_get(exp); |
750 |
int csock = client->sock;
|
751 |
struct nbd_request request;
|
752 |
struct nbd_reply reply;
|
753 |
int rc = -1; |
754 |
int ret;
|
755 |
|
756 |
TRACE("Reading request.");
|
757 |
|
758 |
ret = nbd_do_receive_request(csock, &request, req->data); |
759 |
if (ret == -EIO) {
|
760 |
goto out;
|
761 |
} |
762 |
|
763 |
reply.handle = request.handle; |
764 |
reply.error = 0;
|
765 |
|
766 |
if (ret < 0) { |
767 |
reply.error = -ret; |
768 |
goto error_reply;
|
769 |
} |
770 |
|
771 |
if ((request.from + request.len) > exp->size) {
|
772 |
LOG("From: %" PRIu64 ", Len: %u, Size: %" PRIu64 |
773 |
", Offset: %" PRIu64 "\n", |
774 |
request.from, request.len, |
775 |
(uint64_t)exp->size, exp->dev_offset); |
776 |
LOG("requested operation past EOF--bad client?");
|
777 |
goto invalid_request;
|
778 |
} |
779 |
|
780 |
switch (request.type & NBD_CMD_MASK_COMMAND) {
|
781 |
case NBD_CMD_READ:
|
782 |
TRACE("Request type is READ");
|
783 |
|
784 |
ret = bdrv_read(exp->bs, (request.from + exp->dev_offset) / 512,
|
785 |
req->data, request.len / 512);
|
786 |
if (ret < 0) { |
787 |
LOG("reading from file failed");
|
788 |
reply.error = -ret; |
789 |
goto error_reply;
|
790 |
} |
791 |
|
792 |
TRACE("Read %u byte(s)", request.len);
|
793 |
if (nbd_do_send_reply(csock, &reply, req->data, request.len) < 0) |
794 |
goto out;
|
795 |
break;
|
796 |
case NBD_CMD_WRITE:
|
797 |
TRACE("Request type is WRITE");
|
798 |
|
799 |
if (exp->nbdflags & NBD_FLAG_READ_ONLY) {
|
800 |
TRACE("Server is read-only, return error");
|
801 |
reply.error = EROFS; |
802 |
goto error_reply;
|
803 |
} |
804 |
|
805 |
TRACE("Writing to device");
|
806 |
|
807 |
ret = bdrv_write(exp->bs, (request.from + exp->dev_offset) / 512,
|
808 |
req->data, request.len / 512);
|
809 |
if (ret < 0) { |
810 |
LOG("writing to file failed");
|
811 |
reply.error = -ret; |
812 |
goto error_reply;
|
813 |
} |
814 |
|
815 |
if (request.type & NBD_CMD_FLAG_FUA) {
|
816 |
ret = bdrv_flush(exp->bs); |
817 |
if (ret < 0) { |
818 |
LOG("flush failed");
|
819 |
reply.error = -ret; |
820 |
goto error_reply;
|
821 |
} |
822 |
} |
823 |
|
824 |
if (nbd_do_send_reply(csock, &reply, NULL, 0) < 0) |
825 |
goto out;
|
826 |
break;
|
827 |
case NBD_CMD_DISC:
|
828 |
TRACE("Request type is DISCONNECT");
|
829 |
errno = 0;
|
830 |
return 1; |
831 |
case NBD_CMD_FLUSH:
|
832 |
TRACE("Request type is FLUSH");
|
833 |
|
834 |
ret = bdrv_flush(exp->bs); |
835 |
if (ret < 0) { |
836 |
LOG("flush failed");
|
837 |
reply.error = -ret; |
838 |
} |
839 |
|
840 |
if (nbd_do_send_reply(csock, &reply, NULL, 0) < 0) |
841 |
goto out;
|
842 |
break;
|
843 |
case NBD_CMD_TRIM:
|
844 |
TRACE("Request type is TRIM");
|
845 |
ret = bdrv_discard(exp->bs, (request.from + exp->dev_offset) / 512,
|
846 |
request.len / 512);
|
847 |
if (ret < 0) { |
848 |
LOG("discard failed");
|
849 |
reply.error = -ret; |
850 |
} |
851 |
if (nbd_do_send_reply(csock, &reply, NULL, 0) < 0) |
852 |
goto out;
|
853 |
break;
|
854 |
default:
|
855 |
LOG("invalid request type (%u) received", request.type);
|
856 |
invalid_request:
|
857 |
reply.error = -EINVAL; |
858 |
error_reply:
|
859 |
if (nbd_do_send_reply(csock, &reply, NULL, 0) == -1) |
860 |
goto out;
|
861 |
break;
|
862 |
} |
863 |
|
864 |
TRACE("Request/Reply complete");
|
865 |
|
866 |
rc = 0;
|
867 |
out:
|
868 |
nbd_request_put(exp, req); |
869 |
return rc;
|
870 |
} |
871 |
|
872 |
static void nbd_read(void *opaque) |
873 |
{ |
874 |
NBDClient *client = opaque; |
875 |
|
876 |
nbd_client_get(client); |
877 |
if (nbd_trip(client) != 0) { |
878 |
nbd_client_close(client); |
879 |
} |
880 |
|
881 |
nbd_client_put(client); |
882 |
} |
883 |
|
884 |
NBDClient *nbd_client_new(NBDExport *exp, int csock,
|
885 |
void (*close)(NBDClient *))
|
886 |
{ |
887 |
NBDClient *client; |
888 |
if (nbd_send_negotiate(csock, exp->size, exp->nbdflags) == -1) { |
889 |
return NULL; |
890 |
} |
891 |
client = g_malloc0(sizeof(NBDClient));
|
892 |
client->refcount = 1;
|
893 |
client->exp = exp; |
894 |
client->sock = csock; |
895 |
client->close = close; |
896 |
qemu_set_fd_handler2(csock, NULL, nbd_read, NULL, client); |
897 |
return client;
|
898 |
} |