On Sat, Aug 4, 2018 at 10:58 PM Nir Soffer <nsoffer@redhat.com> wrote:
On Sat, Aug 4, 2018 at 4:04 PM Richard W.M. Jones <rjones@redhat.com> wrote:
This is only lightly tested (against just qemu NBD client), and the
code might be structured a little better as the
_negotiate_handshake_newstyle_options function has now grown to be
huge.  Anyway works for me.

Works for my python nbd client:

$ rm -f /tmp/nbd.sock && src/nbdkit -f plugins/file/.libs/nbdkit-file-plugin.so file=test.raw -e export -U /tmp/nbd.sock

$ python -c "import logging; logging.basicConfig(level=logging.DEBUG); from ovirt_imageio_common import nbd; c = nbd.Client('/tmp/nbd.sock', 'export'); c.write(1024**2, 'it works'); print c.read(1024**2, 8)"
INFO:nbd:Connecting to '/tmp/nbd.sock' 'export'
DEBUG:nbd:Received server flags: 3
DEBUG:nbd:Sending client flags: 1:
DEBUG:nbd:Sending option: 'IHAVEOPT\x00\x00\x00\x07\x00\x00\x00\x0c' data: bytearray(b'\x00\x00\x00\x06export\x00\x00')
DEBUG:nbd:Received reply [magic=3e889045565a9 option=7 type=3 len=12]
DEBUG:nbd:Received export info [size=1073741824 flags=109]
DEBUG:nbd:Received reply [magic=3e889045565a9 option=7 type=1 len=0]
INFO:nbd:Ready for transmission
it works

But we have a bug - server configure to allow access to "export",
but allow access to the default empty "" export.

$ python -c "import logging; logging.basicConfig(level=logging.DEBUG); from ovirt_imageio_common import nbd; c = nbd.Client('/tmp/nbd.sock', '')"
INFO:nbd:Connecting to '/tmp/nbd.sock' ''
DEBUG:nbd:Received server flags: 3
DEBUG:nbd:Sending client flags: 1:
DEBUG:nbd:Sending option: 'IHAVEOPT\x00\x00\x00\x07\x00\x00\x00\x06' data: bytearray(b'\x00\x00\x00\x00\x00\x00')
DEBUG:nbd:Received reply [magic=3e889045565a9 option=7 type=3 len=12]
DEBUG:nbd:Received export info [size=6442450944 flags=109]
DEBUG:nbd:Received reply [magic=3e889045565a9 option=7 type=1 len=0]
INFO:nbd:Ready for transmission

Same with qemu-nbd:

$ qemu-nbd -k /tmp/nbd.sock -t -f raw test.raw --export-name export --cache=none --aio=native --discard=unmap --detect-zeroes=unmap

$ python -c "import logging; logging.basicConfig(level=logging.DEBUG); from ovirt_imageio_common import nbd; c = nbd.Client('/tmp/nbd.sock', '')"
INFO:nbd:Connecting to '/tmp/nbd.sock' ''
DEBUG:nbd:Received server flags: 3
DEBUG:nbd:Sending client flags: 1:
DEBUG:nbd:Sending option: 'IHAVEOPT\x00\x00\x00\x07\x00\x00\x00\x06' data: bytearray(b'\x00\x00\x00\x00\x00\x00')
DEBUG:nbd:Received reply [magic=3e889045565a9 option=7 type=80000006 len=21]
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "ovirt_imageio_common/nbd.py", line 126, in __init__
    self._newstyle_handshake(export_name)
  File "ovirt_imageio_common/nbd.py", line 181, in _newstyle_handshake
    self._receive_go_reply()
  File "ovirt_imageio_common/nbd.py", line 206, in _receive_go_reply
    .format(ERROR_REPLY[reply], message))
ovirt_imageio_common.nbd.Error: The requested export is not available [message=export '' not present])