aboutsummaryrefslogtreecommitdiff
path: root/nbd/server.c
diff options
context:
space:
mode:
Diffstat (limited to 'nbd/server.c')
-rw-r--r--nbd/server.c122
1 files changed, 62 insertions, 60 deletions
diff --git a/nbd/server.c b/nbd/server.c
index 04da1c2f1e..78b08f5891 100644
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -229,6 +229,40 @@ nbd_negotiate_send_rep_err(NBDClient *client, uint32_t type,
return ret;
}
+/* Drop remainder of the current option, and send a reply with the
+ * given error type and message. Return -errno on read or write
+ * failure; or 0 if connection is still live. */
+static int GCC_FMT_ATTR(4, 5)
+nbd_opt_drop(NBDClient *client, uint32_t type, Error **errp,
+ const char *fmt, ...)
+{
+ int ret = nbd_drop(client->ioc, client->optlen, errp);
+ va_list va;
+
+ client->optlen = 0;
+ if (!ret) {
+ va_start(va, fmt);
+ ret = nbd_negotiate_send_rep_verr(client, type, errp, fmt, va);
+ va_end(va);
+ }
+ return ret;
+}
+
+/* Read size bytes from the unparsed payload of the current option.
+ * Return -errno on I/O error, 0 if option was completely handled by
+ * sending a reply about inconsistent lengths, or 1 on success. */
+static int nbd_opt_read(NBDClient *client, void *buffer, size_t size,
+ Error **errp)
+{
+ if (size > client->optlen) {
+ return nbd_opt_drop(client, NBD_REP_ERR_INVALID, errp,
+ "Inconsistent lengths in option %s",
+ nbd_opt_lookup(client->opt));
+ }
+ client->optlen -= size;
+ return qio_channel_read_all(client->ioc, buffer, size, errp) < 0 ? -EIO : 1;
+}
+
/* Send a single NBD_REP_SERVER reply to NBD_OPT_LIST, including payload.
* Return -errno on error, 0 on success. */
static int nbd_negotiate_send_rep_list(NBDClient *client, NBDExport *exp,
@@ -378,14 +412,11 @@ static int nbd_reject_length(NBDClient *client, bool fatal, Error **errp)
int ret;
assert(client->optlen);
- if (nbd_drop(client->ioc, client->optlen, errp) < 0) {
- return -EIO;
- }
- ret = nbd_negotiate_send_rep_err(client, NBD_REP_ERR_INVALID, errp,
- "option '%s' should have zero length",
- nbd_opt_lookup(client->opt));
+ ret = nbd_opt_drop(client, NBD_REP_ERR_INVALID, errp,
+ "option '%s' has unexpected length",
+ nbd_opt_lookup(client->opt));
if (fatal && !ret) {
- error_setg(errp, "option '%s' should have zero length",
+ error_setg(errp, "option '%s' has unexpected length",
nbd_opt_lookup(client->opt));
return -EINVAL;
}
@@ -408,7 +439,6 @@ static int nbd_negotiate_handle_info(NBDClient *client, uint16_t myflags,
bool blocksize = false;
uint32_t sizes[3];
char buf[sizeof(uint64_t) + sizeof(uint16_t)];
- const char *msg;
/* Client sends:
4 bytes: L, name length (can be 0)
@@ -416,48 +446,34 @@ static int nbd_negotiate_handle_info(NBDClient *client, uint16_t myflags,
2 bytes: N, number of requests (can be 0)
N * 2 bytes: N requests
*/
- if (client->optlen < sizeof(namelen) + sizeof(requests)) {
- msg = "overall request too short";
- goto invalid;
- }
- if (nbd_read(client->ioc, &namelen, sizeof(namelen), errp) < 0) {
- return -EIO;
+ rc = nbd_opt_read(client, &namelen, sizeof(namelen), errp);
+ if (rc <= 0) {
+ return rc;
}
be32_to_cpus(&namelen);
- client->optlen -= sizeof(namelen);
- if (namelen > client->optlen - sizeof(requests) ||
- (client->optlen - namelen) % 2)
- {
- msg = "name length is incorrect";
- goto invalid;
- }
if (namelen >= sizeof(name)) {
- msg = "name too long for qemu";
- goto invalid;
+ return nbd_opt_drop(client, NBD_REP_ERR_INVALID, errp,
+ "name too long for qemu");
}
- if (nbd_read(client->ioc, name, namelen, errp) < 0) {
- return -EIO;
+ rc = nbd_opt_read(client, name, namelen, errp);
+ if (rc <= 0) {
+ return rc;
}
name[namelen] = '\0';
- client->optlen -= namelen;
trace_nbd_negotiate_handle_export_name_request(name);
- if (nbd_read(client->ioc, &requests, sizeof(requests), errp) < 0) {
- return -EIO;
+ rc = nbd_opt_read(client, &requests, sizeof(requests), errp);
+ if (rc <= 0) {
+ return rc;
}
be16_to_cpus(&requests);
- client->optlen -= sizeof(requests);
trace_nbd_negotiate_handle_info_requests(requests);
- if (requests != client->optlen / sizeof(request)) {
- msg = "incorrect number of requests for overall length";
- goto invalid;
- }
while (requests--) {
- if (nbd_read(client->ioc, &request, sizeof(request), errp) < 0) {
- return -EIO;
+ rc = nbd_opt_read(client, &request, sizeof(request), errp);
+ if (rc <= 0) {
+ return rc;
}
be16_to_cpus(&request);
- client->optlen -= sizeof(request);
trace_nbd_negotiate_handle_info_request(request,
nbd_info_lookup(request));
/* We care about NBD_INFO_NAME and NBD_INFO_BLOCK_SIZE;
@@ -472,7 +488,9 @@ static int nbd_negotiate_handle_info(NBDClient *client, uint16_t myflags,
break;
}
}
- assert(client->optlen == 0);
+ if (client->optlen) {
+ return nbd_reject_length(client, false, errp);
+ }
exp = nbd_export_find(name);
if (!exp) {
@@ -560,13 +578,6 @@ static int nbd_negotiate_handle_info(NBDClient *client, uint16_t myflags,
rc = 1;
}
return rc;
-
- invalid:
- if (nbd_drop(client->ioc, client->optlen, errp) < 0) {
- return -EIO;
- }
- return nbd_negotiate_send_rep_err(client, NBD_REP_ERR_INVALID,
- errp, "%s", msg);
}
@@ -696,6 +707,7 @@ static int nbd_negotiate_options(NBDClient *client, uint16_t myflags,
return -EINVAL;
}
length = be32_to_cpu(length);
+ assert(!client->optlen);
client->optlen = length;
if (length > NBD_MAX_BUFFER_SIZE) {
@@ -736,14 +748,9 @@ static int nbd_negotiate_options(NBDClient *client, uint16_t myflags,
return -EINVAL;
default:
- if (nbd_drop(client->ioc, length, errp) < 0) {
- return -EIO;
- }
- ret = nbd_negotiate_send_rep_err(client,
- NBD_REP_ERR_TLS_REQD, errp,
- "Option 0x%" PRIx32
- "not permitted before TLS",
- option);
+ ret = nbd_opt_drop(client, NBD_REP_ERR_TLS_REQD, errp,
+ "Option 0x%" PRIx32
+ "not permitted before TLS", option);
/* Let the client keep trying, unless they asked to
* quit. In this mode, we've already sent an error, so
* we can't ack the abort. */
@@ -812,14 +819,9 @@ static int nbd_negotiate_options(NBDClient *client, uint16_t myflags,
break;
default:
- if (nbd_drop(client->ioc, length, errp) < 0) {
- return -EIO;
- }
- ret = nbd_negotiate_send_rep_err(client,
- NBD_REP_ERR_UNSUP, errp,
- "Unsupported option 0x%"
- PRIx32 " (%s)", option,
- nbd_opt_lookup(option));
+ ret = nbd_opt_drop(client, NBD_REP_ERR_UNSUP, errp,
+ "Unsupported option 0x%" PRIx32 " (%s)",
+ option, nbd_opt_lookup(option));
break;
}
} else {
generated by cgit v1.2.3 (git 2.26.2) at 2024-11-27 18:42:56 +0000