• aliguori's avatar
    Support ACLs for controlling VNC access ("Daniel P. Berrange") · 76655d6d
    aliguori authored
    This patch introduces a generic internal API for access control lists
    to be used by network servers in QEMU. It adds support for checking
    these ACL in the VNC server, in two places. The first ACL is for the
    SASL authentication mechanism, checking the SASL username. This ACL
    is called 'vnc.username'. The second is for the TLS authentication
    mechanism, when x509 client certificates are turned on, checking against
    the Distinguished Name of the client. This ACL is called 'vnc.x509dname'
    
    The internal API provides for an ACL with the following characteristics
    
     - A unique name, eg  vnc.username, and vnc.x509dname.
     - A default policy, allow or deny
     - An ordered series of match rules, with allow or deny policy
    
    If none of the match rules apply, then the default policy is
    used.
    
    There is a monitor API to manipulate the ACLs, which I'll describe via
    examples
    
      (qemu) acl show vnc.username
      policy: allow
      (qemu) acl policy vnc.username denya
      acl: policy set to 'deny'
      (qemu) acl allow vnc.username fred
      acl: added rule at position 1
      (qemu) acl allow vnc.username bob
      acl: added rule at position 2
      (qemu) acl allow vnc.username joe 1
      acl: added rule at position 1
      (qemu) acl show vnc.username
      policy: deny
      0: allow fred
      1: allow joe
      2: allow bob
    
    
      (qemu) acl show vnc.x509dname
      policy: allow
      (qemu) acl policy vnc.x509dname deny
      acl: policy set to 'deny'
      (qemu) acl allow vnc.x509dname C=GB,O=ACME,L=London,CN=*
      acl: added rule at position 1
      (qemu) acl allow vnc.x509dname C=GB,O=ACME,L=Boston,CN=bob
      acl: added rule at position 2
      (qemu) acl show vnc.x509dname
      policy: deny
      0: allow C=GB,O=ACME,L=London,CN=*
      1: allow C=GB,O=ACME,L=Boston,CN=bob
    
    By default the VNC server will not use any ACLs, allowing access to
    the server if the user successfully authenticates. To enable use of
    ACLs to restrict user access, the ',acl' flag should be given when
    starting QEMU. The initial ACL activated will be a 'deny all' policy
    and should be customized using monitor commands.
    
    eg enable SASL auth and ACLs
    
        qemu ....  -vnc localhost:1,sasl,acl
    
    The next patch will provide a way to load a pre-defined ACL when
    starting up
    
    
     Makefile        |    6 +
     b/acl.c         |  185 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
     b/acl.h         |   74 ++++++++++++++++++++++
     configure       |   18 +++++
     monitor.c       |   95 ++++++++++++++++++++++++++++
     qemu-doc.texi   |   49 ++++++++++++++
     vnc-auth-sasl.c |   16 +++-
     vnc-auth-sasl.h |    7 ++
     vnc-tls.c       |   19 +++++
     vnc-tls.h       |    3 
     vnc.c           |   21 ++++++
     vnc.h           |    3 
     12 files changed, 491 insertions(+), 5 deletions(-)
    Signed-off-by: default avatarDaniel P. Berrange <berrange@redhat.com>
    Signed-off-by: default avatarAnthony Liguori <aliguori@us.ibm.com>
    
    
    git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6726 c046a42c-6fe2-441c-8c8c-71466251a162
    76655d6d
vnc-auth-sasl.h 2.25 KB