Ensure that all I/O channels created for NBD are given names to distinguish their respective roles. Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
777 lines
22 KiB
C
777 lines
22 KiB
C
/*
|
|
* Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
|
|
*
|
|
* Network Block Device Client Side
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; under version 2 of the License.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include "qemu/osdep.h"
|
|
#include "qapi/error.h"
|
|
#include "nbd-internal.h"
|
|
|
|
static int nbd_errno_to_system_errno(int err)
|
|
{
|
|
switch (err) {
|
|
case NBD_SUCCESS:
|
|
return 0;
|
|
case NBD_EPERM:
|
|
return EPERM;
|
|
case NBD_EIO:
|
|
return EIO;
|
|
case NBD_ENOMEM:
|
|
return ENOMEM;
|
|
case NBD_ENOSPC:
|
|
return ENOSPC;
|
|
default:
|
|
TRACE("Squashing unexpected error %d to EINVAL", err);
|
|
/* fallthrough */
|
|
case NBD_EINVAL:
|
|
return EINVAL;
|
|
}
|
|
}
|
|
|
|
/* Definitions for opaque data types */
|
|
|
|
static QTAILQ_HEAD(, NBDExport) exports = QTAILQ_HEAD_INITIALIZER(exports);
|
|
|
|
/* That's all folks */
|
|
|
|
/* Basic flow for negotiation
|
|
|
|
Server Client
|
|
Negotiate
|
|
|
|
or
|
|
|
|
Server Client
|
|
Negotiate #1
|
|
Option
|
|
Negotiate #2
|
|
|
|
----
|
|
|
|
followed by
|
|
|
|
Server Client
|
|
Request
|
|
Response
|
|
Request
|
|
Response
|
|
...
|
|
...
|
|
Request (type == 2)
|
|
|
|
*/
|
|
|
|
|
|
/* If type represents success, return 1 without further action.
|
|
* If type represents an error reply, consume the rest of the packet on ioc.
|
|
* Then return 0 for unsupported (so the client can fall back to
|
|
* other approaches), or -1 with errp set for other errors.
|
|
*/
|
|
static int nbd_handle_reply_err(QIOChannel *ioc, uint32_t opt, uint32_t type,
|
|
Error **errp)
|
|
{
|
|
uint32_t len;
|
|
char *msg = NULL;
|
|
int result = -1;
|
|
|
|
if (!(type & (1 << 31))) {
|
|
return 1;
|
|
}
|
|
|
|
if (read_sync(ioc, &len, sizeof(len)) != sizeof(len)) {
|
|
error_setg(errp, "failed to read option length");
|
|
return -1;
|
|
}
|
|
len = be32_to_cpu(len);
|
|
if (len) {
|
|
if (len > NBD_MAX_BUFFER_SIZE) {
|
|
error_setg(errp, "server's error message is too long");
|
|
goto cleanup;
|
|
}
|
|
msg = g_malloc(len + 1);
|
|
if (read_sync(ioc, msg, len) != len) {
|
|
error_setg(errp, "failed to read option error message");
|
|
goto cleanup;
|
|
}
|
|
msg[len] = '\0';
|
|
}
|
|
|
|
switch (type) {
|
|
case NBD_REP_ERR_UNSUP:
|
|
TRACE("server doesn't understand request %" PRIx32
|
|
", attempting fallback", opt);
|
|
result = 0;
|
|
goto cleanup;
|
|
|
|
case NBD_REP_ERR_POLICY:
|
|
error_setg(errp, "Denied by server for option %" PRIx32, opt);
|
|
break;
|
|
|
|
case NBD_REP_ERR_INVALID:
|
|
error_setg(errp, "Invalid data length for option %" PRIx32, opt);
|
|
break;
|
|
|
|
case NBD_REP_ERR_TLS_REQD:
|
|
error_setg(errp, "TLS negotiation required before option %" PRIx32,
|
|
opt);
|
|
break;
|
|
|
|
default:
|
|
error_setg(errp, "Unknown error code when asking for option %" PRIx32,
|
|
opt);
|
|
break;
|
|
}
|
|
|
|
if (msg) {
|
|
error_append_hint(errp, "%s\n", msg);
|
|
}
|
|
|
|
cleanup:
|
|
g_free(msg);
|
|
return result;
|
|
}
|
|
|
|
static int nbd_receive_list(QIOChannel *ioc, char **name, Error **errp)
|
|
{
|
|
uint64_t magic;
|
|
uint32_t opt;
|
|
uint32_t type;
|
|
uint32_t len;
|
|
uint32_t namelen;
|
|
int error;
|
|
|
|
*name = NULL;
|
|
if (read_sync(ioc, &magic, sizeof(magic)) != sizeof(magic)) {
|
|
error_setg(errp, "failed to read list option magic");
|
|
return -1;
|
|
}
|
|
magic = be64_to_cpu(magic);
|
|
if (magic != NBD_REP_MAGIC) {
|
|
error_setg(errp, "Unexpected option list magic");
|
|
return -1;
|
|
}
|
|
if (read_sync(ioc, &opt, sizeof(opt)) != sizeof(opt)) {
|
|
error_setg(errp, "failed to read list option");
|
|
return -1;
|
|
}
|
|
opt = be32_to_cpu(opt);
|
|
if (opt != NBD_OPT_LIST) {
|
|
error_setg(errp, "Unexpected option type %" PRIx32 " expected %x",
|
|
opt, NBD_OPT_LIST);
|
|
return -1;
|
|
}
|
|
|
|
if (read_sync(ioc, &type, sizeof(type)) != sizeof(type)) {
|
|
error_setg(errp, "failed to read list option type");
|
|
return -1;
|
|
}
|
|
type = be32_to_cpu(type);
|
|
error = nbd_handle_reply_err(ioc, opt, type, errp);
|
|
if (error <= 0) {
|
|
return error;
|
|
}
|
|
|
|
if (read_sync(ioc, &len, sizeof(len)) != sizeof(len)) {
|
|
error_setg(errp, "failed to read option length");
|
|
return -1;
|
|
}
|
|
len = be32_to_cpu(len);
|
|
|
|
if (type == NBD_REP_ACK) {
|
|
if (len != 0) {
|
|
error_setg(errp, "length too long for option end");
|
|
return -1;
|
|
}
|
|
} else if (type == NBD_REP_SERVER) {
|
|
if (len < sizeof(namelen) || len > NBD_MAX_BUFFER_SIZE) {
|
|
error_setg(errp, "incorrect option length");
|
|
return -1;
|
|
}
|
|
if (read_sync(ioc, &namelen, sizeof(namelen)) != sizeof(namelen)) {
|
|
error_setg(errp, "failed to read option name length");
|
|
return -1;
|
|
}
|
|
namelen = be32_to_cpu(namelen);
|
|
len -= sizeof(namelen);
|
|
if (len < namelen) {
|
|
error_setg(errp, "incorrect option name length");
|
|
return -1;
|
|
}
|
|
if (namelen > NBD_MAX_NAME_SIZE) {
|
|
error_setg(errp, "export name length too long %" PRIu32, namelen);
|
|
return -1;
|
|
}
|
|
|
|
*name = g_new0(char, namelen + 1);
|
|
if (read_sync(ioc, *name, namelen) != namelen) {
|
|
error_setg(errp, "failed to read export name");
|
|
g_free(*name);
|
|
*name = NULL;
|
|
return -1;
|
|
}
|
|
(*name)[namelen] = '\0';
|
|
len -= namelen;
|
|
if (len) {
|
|
char *buf = g_malloc(len + 1);
|
|
if (read_sync(ioc, buf, len) != len) {
|
|
error_setg(errp, "failed to read export description");
|
|
g_free(*name);
|
|
g_free(buf);
|
|
*name = NULL;
|
|
return -1;
|
|
}
|
|
buf[len] = '\0';
|
|
TRACE("Ignoring export description: %s", buf);
|
|
g_free(buf);
|
|
}
|
|
} else {
|
|
error_setg(errp, "Unexpected reply type %" PRIx32 " expected %x",
|
|
type, NBD_REP_SERVER);
|
|
return -1;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
|
|
static int nbd_receive_query_exports(QIOChannel *ioc,
|
|
const char *wantname,
|
|
Error **errp)
|
|
{
|
|
uint64_t magic = cpu_to_be64(NBD_OPTS_MAGIC);
|
|
uint32_t opt = cpu_to_be32(NBD_OPT_LIST);
|
|
uint32_t length = 0;
|
|
bool foundExport = false;
|
|
|
|
TRACE("Querying export list");
|
|
if (write_sync(ioc, &magic, sizeof(magic)) != sizeof(magic)) {
|
|
error_setg(errp, "Failed to send list option magic");
|
|
return -1;
|
|
}
|
|
|
|
if (write_sync(ioc, &opt, sizeof(opt)) != sizeof(opt)) {
|
|
error_setg(errp, "Failed to send list option number");
|
|
return -1;
|
|
}
|
|
|
|
if (write_sync(ioc, &length, sizeof(length)) != sizeof(length)) {
|
|
error_setg(errp, "Failed to send list option length");
|
|
return -1;
|
|
}
|
|
|
|
TRACE("Reading available export names");
|
|
while (1) {
|
|
char *name = NULL;
|
|
int ret = nbd_receive_list(ioc, &name, errp);
|
|
|
|
if (ret < 0) {
|
|
g_free(name);
|
|
name = NULL;
|
|
return -1;
|
|
}
|
|
if (ret == 0) {
|
|
/* Server doesn't support export listing, so
|
|
* we will just assume an export with our
|
|
* wanted name exists */
|
|
foundExport = true;
|
|
break;
|
|
}
|
|
if (name == NULL) {
|
|
TRACE("End of export name list");
|
|
break;
|
|
}
|
|
if (g_str_equal(name, wantname)) {
|
|
foundExport = true;
|
|
TRACE("Found desired export name '%s'", name);
|
|
} else {
|
|
TRACE("Ignored export name '%s'", name);
|
|
}
|
|
g_free(name);
|
|
}
|
|
|
|
if (!foundExport) {
|
|
error_setg(errp, "No export with name '%s' available", wantname);
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static QIOChannel *nbd_receive_starttls(QIOChannel *ioc,
|
|
QCryptoTLSCreds *tlscreds,
|
|
const char *hostname, Error **errp)
|
|
{
|
|
uint64_t magic = cpu_to_be64(NBD_OPTS_MAGIC);
|
|
uint32_t opt = cpu_to_be32(NBD_OPT_STARTTLS);
|
|
uint32_t length = 0;
|
|
uint32_t type;
|
|
QIOChannelTLS *tioc;
|
|
struct NBDTLSHandshakeData data = { 0 };
|
|
|
|
TRACE("Requesting TLS from server");
|
|
if (write_sync(ioc, &magic, sizeof(magic)) != sizeof(magic)) {
|
|
error_setg(errp, "Failed to send option magic");
|
|
return NULL;
|
|
}
|
|
|
|
if (write_sync(ioc, &opt, sizeof(opt)) != sizeof(opt)) {
|
|
error_setg(errp, "Failed to send option number");
|
|
return NULL;
|
|
}
|
|
|
|
if (write_sync(ioc, &length, sizeof(length)) != sizeof(length)) {
|
|
error_setg(errp, "Failed to send option length");
|
|
return NULL;
|
|
}
|
|
|
|
TRACE("Getting TLS reply from server1");
|
|
if (read_sync(ioc, &magic, sizeof(magic)) != sizeof(magic)) {
|
|
error_setg(errp, "failed to read option magic");
|
|
return NULL;
|
|
}
|
|
magic = be64_to_cpu(magic);
|
|
if (magic != NBD_REP_MAGIC) {
|
|
error_setg(errp, "Unexpected option magic");
|
|
return NULL;
|
|
}
|
|
TRACE("Getting TLS reply from server2");
|
|
if (read_sync(ioc, &opt, sizeof(opt)) != sizeof(opt)) {
|
|
error_setg(errp, "failed to read option");
|
|
return NULL;
|
|
}
|
|
opt = be32_to_cpu(opt);
|
|
if (opt != NBD_OPT_STARTTLS) {
|
|
error_setg(errp, "Unexpected option type %" PRIx32 " expected %x",
|
|
opt, NBD_OPT_STARTTLS);
|
|
return NULL;
|
|
}
|
|
|
|
TRACE("Getting TLS reply from server");
|
|
if (read_sync(ioc, &type, sizeof(type)) != sizeof(type)) {
|
|
error_setg(errp, "failed to read option type");
|
|
return NULL;
|
|
}
|
|
type = be32_to_cpu(type);
|
|
if (type != NBD_REP_ACK) {
|
|
error_setg(errp, "Server rejected request to start TLS %" PRIx32,
|
|
type);
|
|
return NULL;
|
|
}
|
|
|
|
TRACE("Getting TLS reply from server");
|
|
if (read_sync(ioc, &length, sizeof(length)) != sizeof(length)) {
|
|
error_setg(errp, "failed to read option length");
|
|
return NULL;
|
|
}
|
|
length = be32_to_cpu(length);
|
|
if (length != 0) {
|
|
error_setg(errp, "Start TLS response was not zero %" PRIu32,
|
|
length);
|
|
return NULL;
|
|
}
|
|
|
|
TRACE("TLS request approved, setting up TLS");
|
|
tioc = qio_channel_tls_new_client(ioc, tlscreds, hostname, errp);
|
|
if (!tioc) {
|
|
return NULL;
|
|
}
|
|
qio_channel_set_name(QIO_CHANNEL(tioc), "nbd-client-tls");
|
|
data.loop = g_main_loop_new(g_main_context_default(), FALSE);
|
|
TRACE("Starting TLS handshake");
|
|
qio_channel_tls_handshake(tioc,
|
|
nbd_tls_handshake,
|
|
&data,
|
|
NULL);
|
|
|
|
if (!data.complete) {
|
|
g_main_loop_run(data.loop);
|
|
}
|
|
g_main_loop_unref(data.loop);
|
|
if (data.error) {
|
|
error_propagate(errp, data.error);
|
|
object_unref(OBJECT(tioc));
|
|
return NULL;
|
|
}
|
|
|
|
return QIO_CHANNEL(tioc);
|
|
}
|
|
|
|
|
|
int nbd_receive_negotiate(QIOChannel *ioc, const char *name, uint16_t *flags,
|
|
QCryptoTLSCreds *tlscreds, const char *hostname,
|
|
QIOChannel **outioc,
|
|
off_t *size, Error **errp)
|
|
{
|
|
char buf[256];
|
|
uint64_t magic, s;
|
|
int rc;
|
|
|
|
TRACE("Receiving negotiation tlscreds=%p hostname=%s.",
|
|
tlscreds, hostname ? hostname : "<null>");
|
|
|
|
rc = -EINVAL;
|
|
|
|
if (outioc) {
|
|
*outioc = NULL;
|
|
}
|
|
if (tlscreds && !outioc) {
|
|
error_setg(errp, "Output I/O channel required for TLS");
|
|
goto fail;
|
|
}
|
|
|
|
if (read_sync(ioc, buf, 8) != 8) {
|
|
error_setg(errp, "Failed to read data");
|
|
goto fail;
|
|
}
|
|
|
|
buf[8] = '\0';
|
|
if (strlen(buf) == 0) {
|
|
error_setg(errp, "Server connection closed unexpectedly");
|
|
goto fail;
|
|
}
|
|
|
|
TRACE("Magic is %c%c%c%c%c%c%c%c",
|
|
qemu_isprint(buf[0]) ? buf[0] : '.',
|
|
qemu_isprint(buf[1]) ? buf[1] : '.',
|
|
qemu_isprint(buf[2]) ? buf[2] : '.',
|
|
qemu_isprint(buf[3]) ? buf[3] : '.',
|
|
qemu_isprint(buf[4]) ? buf[4] : '.',
|
|
qemu_isprint(buf[5]) ? buf[5] : '.',
|
|
qemu_isprint(buf[6]) ? buf[6] : '.',
|
|
qemu_isprint(buf[7]) ? buf[7] : '.');
|
|
|
|
if (memcmp(buf, "NBDMAGIC", 8) != 0) {
|
|
error_setg(errp, "Invalid magic received");
|
|
goto fail;
|
|
}
|
|
|
|
if (read_sync(ioc, &magic, sizeof(magic)) != sizeof(magic)) {
|
|
error_setg(errp, "Failed to read magic");
|
|
goto fail;
|
|
}
|
|
magic = be64_to_cpu(magic);
|
|
TRACE("Magic is 0x%" PRIx64, magic);
|
|
|
|
if (magic == NBD_OPTS_MAGIC) {
|
|
uint32_t clientflags = 0;
|
|
uint32_t opt;
|
|
uint32_t namesize;
|
|
uint16_t globalflags;
|
|
bool fixedNewStyle = false;
|
|
|
|
if (read_sync(ioc, &globalflags, sizeof(globalflags)) !=
|
|
sizeof(globalflags)) {
|
|
error_setg(errp, "Failed to read server flags");
|
|
goto fail;
|
|
}
|
|
globalflags = be16_to_cpu(globalflags);
|
|
TRACE("Global flags are %" PRIx32, globalflags);
|
|
if (globalflags & NBD_FLAG_FIXED_NEWSTYLE) {
|
|
fixedNewStyle = true;
|
|
TRACE("Server supports fixed new style");
|
|
clientflags |= NBD_FLAG_C_FIXED_NEWSTYLE;
|
|
}
|
|
/* client requested flags */
|
|
clientflags = cpu_to_be32(clientflags);
|
|
if (write_sync(ioc, &clientflags, sizeof(clientflags)) !=
|
|
sizeof(clientflags)) {
|
|
error_setg(errp, "Failed to send clientflags field");
|
|
goto fail;
|
|
}
|
|
if (tlscreds) {
|
|
if (fixedNewStyle) {
|
|
*outioc = nbd_receive_starttls(ioc, tlscreds, hostname, errp);
|
|
if (!*outioc) {
|
|
goto fail;
|
|
}
|
|
ioc = *outioc;
|
|
} else {
|
|
error_setg(errp, "Server does not support STARTTLS");
|
|
goto fail;
|
|
}
|
|
}
|
|
if (!name) {
|
|
TRACE("Using default NBD export name \"\"");
|
|
name = "";
|
|
}
|
|
if (fixedNewStyle) {
|
|
/* Check our desired export is present in the
|
|
* server export list. Since NBD_OPT_EXPORT_NAME
|
|
* cannot return an error message, running this
|
|
* query gives us good error reporting if the
|
|
* server required TLS
|
|
*/
|
|
if (nbd_receive_query_exports(ioc, name, errp) < 0) {
|
|
goto fail;
|
|
}
|
|
}
|
|
/* write the export name */
|
|
magic = cpu_to_be64(magic);
|
|
if (write_sync(ioc, &magic, sizeof(magic)) != sizeof(magic)) {
|
|
error_setg(errp, "Failed to send export name magic");
|
|
goto fail;
|
|
}
|
|
opt = cpu_to_be32(NBD_OPT_EXPORT_NAME);
|
|
if (write_sync(ioc, &opt, sizeof(opt)) != sizeof(opt)) {
|
|
error_setg(errp, "Failed to send export name option number");
|
|
goto fail;
|
|
}
|
|
namesize = cpu_to_be32(strlen(name));
|
|
if (write_sync(ioc, &namesize, sizeof(namesize)) !=
|
|
sizeof(namesize)) {
|
|
error_setg(errp, "Failed to send export name length");
|
|
goto fail;
|
|
}
|
|
if (write_sync(ioc, (char *)name, strlen(name)) != strlen(name)) {
|
|
error_setg(errp, "Failed to send export name");
|
|
goto fail;
|
|
}
|
|
|
|
if (read_sync(ioc, &s, sizeof(s)) != sizeof(s)) {
|
|
error_setg(errp, "Failed to read export length");
|
|
goto fail;
|
|
}
|
|
*size = be64_to_cpu(s);
|
|
|
|
if (read_sync(ioc, flags, sizeof(*flags)) != sizeof(*flags)) {
|
|
error_setg(errp, "Failed to read export flags");
|
|
goto fail;
|
|
}
|
|
be16_to_cpus(flags);
|
|
} else if (magic == NBD_CLIENT_MAGIC) {
|
|
uint32_t oldflags;
|
|
|
|
if (name) {
|
|
error_setg(errp, "Server does not support export names");
|
|
goto fail;
|
|
}
|
|
if (tlscreds) {
|
|
error_setg(errp, "Server does not support STARTTLS");
|
|
goto fail;
|
|
}
|
|
|
|
if (read_sync(ioc, &s, sizeof(s)) != sizeof(s)) {
|
|
error_setg(errp, "Failed to read export length");
|
|
goto fail;
|
|
}
|
|
*size = be64_to_cpu(s);
|
|
TRACE("Size is %" PRIu64, *size);
|
|
|
|
if (read_sync(ioc, &oldflags, sizeof(oldflags)) != sizeof(oldflags)) {
|
|
error_setg(errp, "Failed to read export flags");
|
|
goto fail;
|
|
}
|
|
be32_to_cpus(&oldflags);
|
|
if (oldflags & ~0xffff) {
|
|
error_setg(errp, "Unexpected export flags %0x" PRIx32, oldflags);
|
|
goto fail;
|
|
}
|
|
*flags = oldflags;
|
|
} else {
|
|
error_setg(errp, "Bad magic received");
|
|
goto fail;
|
|
}
|
|
|
|
TRACE("Size is %" PRIu64 ", export flags %" PRIx16, *size, *flags);
|
|
if (read_sync(ioc, &buf, 124) != 124) {
|
|
error_setg(errp, "Failed to read reserved block");
|
|
goto fail;
|
|
}
|
|
rc = 0;
|
|
|
|
fail:
|
|
return rc;
|
|
}
|
|
|
|
#ifdef __linux__
|
|
int nbd_init(int fd, QIOChannelSocket *sioc, uint16_t flags, off_t size)
|
|
{
|
|
unsigned long sectors = size / BDRV_SECTOR_SIZE;
|
|
if (size / BDRV_SECTOR_SIZE != sectors) {
|
|
LOG("Export size %lld too large for 32-bit kernel", (long long) size);
|
|
return -E2BIG;
|
|
}
|
|
|
|
TRACE("Setting NBD socket");
|
|
|
|
if (ioctl(fd, NBD_SET_SOCK, (unsigned long) sioc->fd) < 0) {
|
|
int serrno = errno;
|
|
LOG("Failed to set NBD socket");
|
|
return -serrno;
|
|
}
|
|
|
|
TRACE("Setting block size to %lu", (unsigned long)BDRV_SECTOR_SIZE);
|
|
|
|
if (ioctl(fd, NBD_SET_BLKSIZE, (unsigned long)BDRV_SECTOR_SIZE) < 0) {
|
|
int serrno = errno;
|
|
LOG("Failed setting NBD block size");
|
|
return -serrno;
|
|
}
|
|
|
|
TRACE("Setting size to %lu block(s)", sectors);
|
|
if (size % BDRV_SECTOR_SIZE) {
|
|
TRACE("Ignoring trailing %d bytes of export",
|
|
(int) (size % BDRV_SECTOR_SIZE));
|
|
}
|
|
|
|
if (ioctl(fd, NBD_SET_SIZE_BLOCKS, sectors) < 0) {
|
|
int serrno = errno;
|
|
LOG("Failed setting size (in blocks)");
|
|
return -serrno;
|
|
}
|
|
|
|
if (ioctl(fd, NBD_SET_FLAGS, (unsigned long) flags) < 0) {
|
|
if (errno == ENOTTY) {
|
|
int read_only = (flags & NBD_FLAG_READ_ONLY) != 0;
|
|
TRACE("Setting readonly attribute");
|
|
|
|
if (ioctl(fd, BLKROSET, (unsigned long) &read_only) < 0) {
|
|
int serrno = errno;
|
|
LOG("Failed setting read-only attribute");
|
|
return -serrno;
|
|
}
|
|
} else {
|
|
int serrno = errno;
|
|
LOG("Failed setting flags");
|
|
return -serrno;
|
|
}
|
|
}
|
|
|
|
TRACE("Negotiation ended");
|
|
|
|
return 0;
|
|
}
|
|
|
|
int nbd_client(int fd)
|
|
{
|
|
int ret;
|
|
int serrno;
|
|
|
|
TRACE("Doing NBD loop");
|
|
|
|
ret = ioctl(fd, NBD_DO_IT);
|
|
if (ret < 0 && errno == EPIPE) {
|
|
/* NBD_DO_IT normally returns EPIPE when someone has disconnected
|
|
* the socket via NBD_DISCONNECT. We do not want to return 1 in
|
|
* that case.
|
|
*/
|
|
ret = 0;
|
|
}
|
|
serrno = errno;
|
|
|
|
TRACE("NBD loop returned %d: %s", ret, strerror(serrno));
|
|
|
|
TRACE("Clearing NBD queue");
|
|
ioctl(fd, NBD_CLEAR_QUE);
|
|
|
|
TRACE("Clearing NBD socket");
|
|
ioctl(fd, NBD_CLEAR_SOCK);
|
|
|
|
errno = serrno;
|
|
return ret;
|
|
}
|
|
|
|
int nbd_disconnect(int fd)
|
|
{
|
|
ioctl(fd, NBD_CLEAR_QUE);
|
|
ioctl(fd, NBD_DISCONNECT);
|
|
ioctl(fd, NBD_CLEAR_SOCK);
|
|
return 0;
|
|
}
|
|
|
|
#else
|
|
int nbd_init(int fd, QIOChannelSocket *ioc, uint16_t flags, off_t size)
|
|
{
|
|
return -ENOTSUP;
|
|
}
|
|
|
|
int nbd_client(int fd)
|
|
{
|
|
return -ENOTSUP;
|
|
}
|
|
int nbd_disconnect(int fd)
|
|
{
|
|
return -ENOTSUP;
|
|
}
|
|
#endif
|
|
|
|
ssize_t nbd_send_request(QIOChannel *ioc, struct nbd_request *request)
|
|
{
|
|
uint8_t buf[NBD_REQUEST_SIZE];
|
|
ssize_t ret;
|
|
|
|
TRACE("Sending request to server: "
|
|
"{ .from = %" PRIu64", .len = %" PRIu32 ", .handle = %" PRIu64
|
|
", .type=%" PRIu32 " }",
|
|
request->from, request->len, request->handle, request->type);
|
|
|
|
stl_be_p(buf, NBD_REQUEST_MAGIC);
|
|
stl_be_p(buf + 4, request->type);
|
|
stq_be_p(buf + 8, request->handle);
|
|
stq_be_p(buf + 16, request->from);
|
|
stl_be_p(buf + 24, request->len);
|
|
|
|
ret = write_sync(ioc, buf, sizeof(buf));
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
|
|
if (ret != sizeof(buf)) {
|
|
LOG("writing to socket failed");
|
|
return -EINVAL;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
ssize_t nbd_receive_reply(QIOChannel *ioc, struct nbd_reply *reply)
|
|
{
|
|
uint8_t buf[NBD_REPLY_SIZE];
|
|
uint32_t magic;
|
|
ssize_t ret;
|
|
|
|
ret = read_sync(ioc, buf, sizeof(buf));
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
|
|
if (ret != sizeof(buf)) {
|
|
LOG("read failed");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Reply
|
|
[ 0 .. 3] magic (NBD_REPLY_MAGIC)
|
|
[ 4 .. 7] error (0 == no error)
|
|
[ 7 .. 15] handle
|
|
*/
|
|
|
|
magic = ldl_be_p(buf);
|
|
reply->error = ldl_be_p(buf + 4);
|
|
reply->handle = ldq_be_p(buf + 8);
|
|
|
|
reply->error = nbd_errno_to_system_errno(reply->error);
|
|
|
|
TRACE("Got reply: { magic = 0x%" PRIx32 ", .error = % " PRId32
|
|
", handle = %" PRIu64" }",
|
|
magic, reply->error, reply->handle);
|
|
|
|
if (magic != NBD_REPLY_MAGIC) {
|
|
LOG("invalid magic (got 0x%" PRIx32 ")", magic);
|
|
return -EINVAL;
|
|
}
|
|
return 0;
|
|
}
|
|
|