/*
- * Copyright (C) 2016-2018 Red Hat, Inc.
+ * Copyright (C) 2016-2019 Red Hat, Inc.
*
* Network Block Device Client Side
#include "qemu/osdep.h"
#include "qapi/error.h"
+#include "qemu/queue.h"
#include "trace.h"
#include "nbd-internal.h"
#include "qemu/cutils.h"
return 0;
}
-/* If reply represents success, return 1 without further action.
- * If reply represents an error, consume the optional payload 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.
+/*
+ * If reply represents success, return 1 without further action. If
+ * reply represents an error, consume the optional payload of the
+ * packet on ioc. Then return 0 for unsupported (so the client can
+ * fall back to other approaches), where @strict determines if only
+ * ERR_UNSUP or all errors fit that category, or -1 with errp set for
+ * other errors.
*/
static int nbd_handle_reply_err(QIOChannel *ioc, NBDOptionReply *reply,
- Error **errp)
+ bool strict, Error **errp)
{
- char *msg = NULL;
- int result = -1;
+ g_autofree char *msg = NULL;
if (!(reply->type & (1 << 31))) {
return 1;
error_setg(errp, "server error %" PRIu32
" (%s) message is too long",
reply->type, nbd_rep_lookup(reply->type));
- goto cleanup;
+ goto err;
}
msg = g_malloc(reply->length + 1);
if (nbd_read(ioc, msg, reply->length, NULL, errp) < 0) {
error_prepend(errp, "Failed to read option error %" PRIu32
" (%s) message: ",
reply->type, nbd_rep_lookup(reply->type));
- goto cleanup;
+ goto err;
}
msg[reply->length] = '\0';
trace_nbd_server_error_msg(reply->type,
nbd_reply_type_lookup(reply->type), msg);
}
- switch (reply->type) {
- case NBD_REP_ERR_UNSUP:
- trace_nbd_reply_err_unsup(reply->option, nbd_opt_lookup(reply->option));
- result = 0;
- goto cleanup;
+ if (reply->type == NBD_REP_ERR_UNSUP || !strict) {
+ trace_nbd_reply_err_ignored(reply->option,
+ nbd_opt_lookup(reply->option),
+ reply->type, nbd_rep_lookup(reply->type));
+ return 0;
+ }
+ switch (reply->type) {
case NBD_REP_ERR_POLICY:
error_setg(errp, "Denied by server for option %" PRIu32 " (%s)",
reply->option, nbd_opt_lookup(reply->option));
case NBD_REP_ERR_TLS_REQD:
error_setg(errp, "TLS negotiation required before option %" PRIu32
" (%s)", reply->option, nbd_opt_lookup(reply->option));
+ error_append_hint(errp, "Did you forget a valid tls-creds?\n");
break;
case NBD_REP_ERR_UNKNOWN:
error_append_hint(errp, "server reported: %s\n", msg);
}
- cleanup:
- g_free(msg);
- if (result < 0) {
- nbd_send_opt_abort(ioc);
- }
- return result;
+ err:
+ nbd_send_opt_abort(ioc);
+ return -1;
}
/* nbd_receive_list:
static int nbd_receive_list(QIOChannel *ioc, char **name, char **description,
Error **errp)
{
- int ret = -1;
NBDOptionReply reply;
uint32_t len;
uint32_t namelen;
- char *local_name = NULL;
- char *local_desc = NULL;
+ g_autofree char *local_name = NULL;
+ g_autofree char *local_desc = NULL;
int error;
if (nbd_receive_option_reply(ioc, NBD_OPT_LIST, &reply, errp) < 0) {
return -1;
}
- error = nbd_handle_reply_err(ioc, &reply, errp);
+ error = nbd_handle_reply_err(ioc, &reply, true, errp);
if (error <= 0) {
return error;
}
return -1;
}
len -= sizeof(namelen);
- if (len < namelen) {
- error_setg(errp, "incorrect option name length");
+ if (len < namelen || namelen > NBD_MAX_STRING_SIZE) {
+ error_setg(errp, "incorrect name length in server's list response");
nbd_send_opt_abort(ioc);
return -1;
}
local_name = g_malloc(namelen + 1);
if (nbd_read(ioc, local_name, namelen, "export name", errp) < 0) {
nbd_send_opt_abort(ioc);
- goto out;
+ return -1;
}
local_name[namelen] = '\0';
len -= namelen;
if (len) {
+ if (len > NBD_MAX_STRING_SIZE) {
+ error_setg(errp, "incorrect description length in server's "
+ "list response");
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
local_desc = g_malloc(len + 1);
if (nbd_read(ioc, local_desc, len, "export description", errp) < 0) {
nbd_send_opt_abort(ioc);
- goto out;
+ return -1;
}
local_desc[len] = '\0';
}
trace_nbd_receive_list(local_name, local_desc ?: "");
- *name = local_name;
- local_name = NULL;
+ *name = g_steal_pointer(&local_name);
if (description) {
- *description = local_desc;
- local_desc = NULL;
+ *description = g_steal_pointer(&local_desc);
}
- ret = 1;
-
- out:
- g_free(local_name);
- g_free(local_desc);
- return ret;
+ return 1;
}
if (nbd_receive_option_reply(ioc, opt, &reply, errp) < 0) {
return -1;
}
- error = nbd_handle_reply_err(ioc, &reply, errp);
+ error = nbd_handle_reply_err(ioc, &reply, true, errp);
if (error <= 0) {
return error;
}
nbd_send_opt_abort(ioc);
return -1;
}
+ if (info->min_block &&
+ !QEMU_IS_ALIGNED(info->size, info->min_block)) {
+ error_setg(errp, "export size %" PRIu64 " is not multiple of "
+ "minimum block size %" PRIu32, info->size,
+ info->min_block);
+ nbd_send_opt_abort(ioc);
+ return -1;
+ }
trace_nbd_receive_negotiate_size_flags(info->size, info->flags);
break;
break;
default:
+ /*
+ * Not worth the bother to check if NBD_INFO_NAME or
+ * NBD_INFO_DESCRIPTION exceed NBD_MAX_STRING_SIZE.
+ */
trace_nbd_opt_info_unknown(type, nbd_info_lookup(type));
if (nbd_drop(ioc, len, errp) < 0) {
error_prepend(errp, "Failed to read info payload: ");
}
}
-/* nbd_request_simple_option: Send an option request, and parse the reply
+/*
+ * nbd_request_simple_option: Send an option request, and parse the reply.
+ * @strict controls whether ERR_UNSUP or all errors produce 0 status.
* return 1 for successful negotiation,
* 0 if operation is unsupported,
* -1 with errp set for any other error
*/
-static int nbd_request_simple_option(QIOChannel *ioc, int opt, Error **errp)
+static int nbd_request_simple_option(QIOChannel *ioc, int opt, bool strict,
+ Error **errp)
{
NBDOptionReply reply;
int error;
if (nbd_receive_option_reply(ioc, opt, &reply, errp) < 0) {
return -1;
}
- error = nbd_handle_reply_err(ioc, &reply, errp);
+ error = nbd_handle_reply_err(ioc, &reply, strict, errp);
if (error <= 0) {
return error;
}
QIOChannelTLS *tioc;
struct NBDTLSHandshakeData data = { 0 };
- ret = nbd_request_simple_option(ioc, NBD_OPT_STARTTLS, errp);
+ ret = nbd_request_simple_option(ioc, NBD_OPT_STARTTLS, true, errp);
if (ret <= 0) {
if (ret == 0) {
error_setg(errp, "Server don't support STARTTLS option");
char *p;
data_len = sizeof(export_len) + export_len + sizeof(queries);
+ assert(export_len <= NBD_MAX_STRING_SIZE);
if (query) {
query_len = strlen(query);
data_len += sizeof(query_len) + query_len;
+ assert(query_len <= NBD_MAX_STRING_SIZE);
} else {
assert(opt == NBD_OPT_LIST_META_CONTEXT);
}
return -1;
}
- ret = nbd_handle_reply_err(ioc, &reply, errp);
+ ret = nbd_handle_reply_err(ioc, &reply, false, errp);
if (ret <= 0) {
return ret;
}
* 2: server is newstyle, but lacks structured replies
* 3: server is newstyle and set up for structured replies
*/
-static int nbd_start_negotiate(QIOChannel *ioc, QCryptoTLSCreds *tlscreds,
+static int nbd_start_negotiate(AioContext *aio_context, QIOChannel *ioc,
+ QCryptoTLSCreds *tlscreds,
const char *hostname, QIOChannel **outioc,
bool structured_reply, bool *zeroes,
Error **errp)
return -EINVAL;
}
ioc = *outioc;
+ if (aio_context) {
+ qio_channel_set_blocking(ioc, false, NULL);
+ qio_channel_attach_aio_context(ioc, aio_context);
+ }
} else {
error_setg(errp, "Server does not support STARTTLS");
return -EINVAL;
if (structured_reply) {
result = nbd_request_simple_option(ioc,
NBD_OPT_STRUCTURED_REPLY,
- errp);
+ false, errp);
if (result < 0) {
return -EINVAL;
}
* Returns: negative errno: failure talking to server
* 0: server is connected
*/
-int nbd_receive_negotiate(QIOChannel *ioc, QCryptoTLSCreds *tlscreds,
+int nbd_receive_negotiate(AioContext *aio_context, QIOChannel *ioc,
+ QCryptoTLSCreds *tlscreds,
const char *hostname, QIOChannel **outioc,
NBDExportInfo *info, Error **errp)
{
bool zeroes;
bool base_allocation = info->base_allocation;
- assert(info->name);
+ assert(info->name && strlen(info->name) <= NBD_MAX_STRING_SIZE);
trace_nbd_receive_negotiate_name(info->name);
- result = nbd_start_negotiate(ioc, tlscreds, hostname, outioc,
+ result = nbd_start_negotiate(aio_context, ioc, tlscreds, hostname, outioc,
info->structured_reply, &zeroes, errp);
info->structured_reply = false;
QIOChannel *sioc = NULL;
*info = NULL;
- result = nbd_start_negotiate(ioc, tlscreds, hostname, &sioc, true, NULL,
- errp);
+ result = nbd_start_negotiate(NULL, ioc, tlscreds, hostname, &sioc, true,
+ NULL, errp);
if (tlscreds && sioc) {
ioc = sioc;
}
* negative errno on failure (errp is set)
*/
static inline int coroutine_fn
-nbd_read_eof(QIOChannel *ioc, void *buffer, size_t size, Error **errp)
+nbd_read_eof(BlockDriverState *bs, QIOChannel *ioc, void *buffer, size_t size,
+ Error **errp)
{
- int ret;
+ bool partial = false;
assert(size);
- ret = qio_channel_read_all_eof(ioc, buffer, size, errp);
- if (ret < 0) {
- ret = -EIO;
+ while (size > 0) {
+ struct iovec iov = { .iov_base = buffer, .iov_len = size };
+ ssize_t len;
+
+ len = qio_channel_readv(ioc, &iov, 1, errp);
+ if (len == QIO_CHANNEL_ERR_BLOCK) {
+ bdrv_dec_in_flight(bs);
+ qio_channel_yield(ioc, G_IO_IN);
+ bdrv_inc_in_flight(bs);
+ continue;
+ } else if (len < 0) {
+ return -EIO;
+ } else if (len == 0) {
+ if (partial) {
+ error_setg(errp,
+ "Unexpected end-of-file before all bytes were read");
+ return -EIO;
+ } else {
+ return 0;
+ }
+ }
+
+ partial = true;
+ size -= len;
+ buffer = (uint8_t*) buffer + len;
}
- return ret;
+ return 1;
}
/* nbd_receive_reply
+ *
+ * Decreases bs->in_flight while waiting for a new reply. This yield is where
+ * we wait indefinitely and the coroutine must be able to be safely reentered
+ * for nbd_client_attach_aio_context().
+ *
* Returns 1 on success
* 0 on eof, when no data was read (errp is not set)
* negative errno on failure (errp is set)
*/
-int coroutine_fn nbd_receive_reply(QIOChannel *ioc, NBDReply *reply,
- Error **errp)
+int coroutine_fn nbd_receive_reply(BlockDriverState *bs, QIOChannel *ioc,
+ NBDReply *reply, Error **errp)
{
int ret;
const char *type;
- ret = nbd_read_eof(ioc, &reply->magic, sizeof(reply->magic), errp);
+ ret = nbd_read_eof(bs, ioc, &reply->magic, sizeof(reply->magic), errp);
if (ret <= 0) {
return ret;
}