[Qemu-devel] [PATCH v2 00/15] Implement TLS support to QEMU NBD server & client

[Daniel P. Berrange]

This is an update of the series previously posted:

  v1: https://lists.gnu.org/archive/html/qemu-devel/2015-11/msg06126.html

This series of patches implements support for TLS in the QEMU NBD
server and client code.

It is implementing the NBD_OPT_STARTTLS option that was previously
discussed here:

  https://www.redhat.com/archives/libvir-list/2014-October/msg00506.html

And is also described in the NBD spec here:

  https://github.com/yoe/nbd/blob/master/doc/proto.md

To ensure that clients always get a suitable error message from the
NBD server when it is configured with TLS, a client speaking the
new style protocol will always send NBD_OPT_LIST as the first thing
it does, so that we can see the NBD_REP_ERR_TLS_REQD response.

Usage of TLS is described in the commit messages for each patch,
but for sake of people who don't want to explore the series, here's
the summary

Starting QEMU system emulator with a disk backed by an TLS encrypted
NBD export

  $ qemu-system-x86_64 \
       -object 
tls-creds-x509,id=tls0,endpoint=client,dir=/home/berrange/security/qemutls \
       -drive driver=nbd,host=localhost,port=9000,tls-creds=tls0

Starting a standalone NBD server providing a TLS encrypted NBD export

  $ qemu-nbd \
       --object 
tls-creds-x509,id=tls0,endpoint=server,dir=/home/berrange/security/qemutls
       --tls-creds tls0 \
       --exportname default

NB, exportname is mandatory, since TLS requires the fixed-new style
NBD protocol negotiation.

Starting a QEMU system emulator built-in NBD server

  $ qemu-system-x86_64 \
       -qmp unix:/tmp/qmp,server \
       -hda /home/berrange/Fedora-Server-netinst-x86_64-23.iso \
       -object 
tls-creds-x509,id=tls0,dir=/home/berrange/security/qemutls,endpoint=server

  $ qmp-shell /tmp/qmp
    (qmp) nbd-server-start addr={"host":"localhost","port":"9000"} 
tls-creds=tls0
    (qmp) nbd-server-add device=ide0-hd0

The first 2 patches may be familiar as they are also posted
as part of a block device series:

  https://lists.gnu.org/archive/html/qemu-devel/2015-12/msg04354.html

The next 4 patches are the conversion to the I/O channels
framework.

The next 5 patches are general tweaks to QEMU's impl of the
NBD protocol for better compliance and/or future proofing.

The next patch provides the NBD protocol TLS implementation.

The final 3 patches allow TLS to be enabled in the QEMU NBD
client and servers.

Changed in v2:

 - Fix error codes used during NBD TLS option negotiate
 - Update patch with helpers for UserCreatable object types

Daniel P. Berrange (15):
  qom: add helpers for UserCreatable object types
  qemu-nbd: add support for --object command line arg
  nbd: convert block client to use I/O channels for connection setup
  nbd: convert qemu-nbd server to use I/O channels for connection setup
  nbd: convert blockdev NBD server to use I/O channels for connection
    setup
  nbd: convert to using I/O channels for actual socket I/O
  nbd: invert client logic for negotiating protocol version
  nbd: make server compliant with fixed newstyle spec
  nbd: make client request fixed new style if advertized
  nbd: allow setting of an export name for qemu-nbd server
  nbd: pick first exported volume if no export name is requested
  nbd: implement TLS support in the protocol negotiation
  nbd: enable use of TLS with NBD block driver
  nbd: enable use of TLS with qemu-nbd server
  nbd: enable use of TLS with nbd-server-start command

 Makefile                        |   6 +-
 block/nbd-client.c              |  74 ++--
 block/nbd-client.h              |  10 +-
 block/nbd.c                     | 105 ++++-
 blockdev-nbd.c                  | 132 +++++-
 hmp.c                           |  54 +--
 include/block/nbd.h             |  27 +-
 include/monitor/monitor.h       |   3 -
 include/qom/object_interfaces.h |  48 +++
 nbd.c                           | 895 ++++++++++++++++++++++++++++++++--------
 qapi/block.json                 |   4 +-
 qemu-nbd.c                      | 210 ++++++++--
 qemu-nbd.texi                   |  13 +
 qmp-commands.hx                 |   2 +-
 qmp.c                           |  76 +---
 qom/object_interfaces.c         | 139 +++++++
 tests/Makefile                  |   2 +-
 vl.c                            |  48 +--
 18 files changed, 1395 insertions(+), 453 deletions(-)

-- 
2.5.0