From: Max Reitz <mre...@redhat.com>
The client flags are sent exactly once overall, not once per option.
Signed-off-by: Max Reitz <mre...@redhat.com>
Message-Id: <1424887718-10800-19-git-send-email-mre...@redhat.com>
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
nbd.c | 49 +++++++++++++++++++++++++++++--------------------
1 file changed, 29 insertions(+), 20 deletions(-)
diff --git a/nbd.c b/nbd.c
index 3d550f7..fb8a4d4 100644
--- a/nbd.c
+++ b/nbd.c
@@ -350,30 +350,39 @@ fail:
static int nbd_receive_options(NBDClient *client)
{
+ int csock = client->sock;
+ uint32_t flags;
+
+ /* Client sends:
+ [ 0 .. 3] client flags
+
+ [ 0 .. 7] NBD_OPTS_MAGIC
+ [ 8 .. 11] NBD option
+ [12 .. 15] Data length
+ ... Rest of request
+
+ [ 0 .. 7] NBD_OPTS_MAGIC
+ [ 8 .. 11] Second NBD option
+ [12 .. 15] Data length
+ ... Rest of request
+ */
+
+ if (read_sync(csock, &flags, sizeof(flags)) != sizeof(flags)) {
+ LOG("read failed");
+ return -EIO;
+ }
+ TRACE("Checking client flags");
+ be32_to_cpus(&flags);
+ if (flags != 0 && flags != NBD_FLAG_C_FIXED_NEWSTYLE) {
+ LOG("Bad client flags received");
+ return -EIO;
+ }
+
while (1) {
- int csock = client->sock, ret;
+ int ret;
uint32_t tmp, length;
uint64_t magic;
- /* Client sends:
- [ 0 .. 3] client flags
- [ 4 .. 11] NBD_OPTS_MAGIC
- [12 .. 15] NBD option
- [16 .. 19] length
- ... Rest of request
- */
-
- if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) {
- LOG("read failed");
- return -EINVAL;
- }
- TRACE("Checking client flags");
- tmp = be32_to_cpu(tmp);
- if (tmp != 0 && tmp != NBD_FLAG_C_FIXED_NEWSTYLE) {
- LOG("Bad client flags received");
- return -EINVAL;
- }
-
if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) {
LOG("read failed");
return -EINVAL;
--
2.3.0
