Re: [Qemu-devel] [PATCH v2] qga: add guest-set-admin-password command

["Daniel P. Berrange" <berrange@redhat.com>]

On Tue, Feb 03, 2015 at 03:16:08PM -0700, Eric Blake wrote:
> On 01/12/2015 08:58 AM, Daniel P. Berrange wrote:
> > Add a new 'guest-set-admin-password' command for changing the
> > root/administrator password. This command is needed to allow
> > OpenStack to support its API for changing the admin password
> > on a running guest.
> > 
> > Accepts either the raw password string:
> > 
> > $ virsh -c qemu:///system  qemu-agent-command f21x86_64 \
> >    '{ "execute": "guest-set-admin-password", "arguments":
> >      { "crypted": false, "password": "12345678" } }'
> >   {"return":{}}
> > 
> > Or a pre-encrypted string (recommended)
> > 
> > $ virsh -c qemu:///system  qemu-agent-command f21x86_64 \
> >    '{ "execute": "guest-set-admin-password", "arguments":
> >      { "crypted": true, "password":
> >         "$6$T9O/j/aGPrE...snip....rQoRN4F0.GG0MPjNUNyml." } }'
> > 
> > NB windows support is desirable, but not implemented in this
> > patch.
> > 
> > Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
> > ---
> >  qga/commands-posix.c | 90 ++++++++++++++++++++++++++++++++++++++++++++++++++++
> >  qga/commands-win32.c |  6 ++++
> >  qga/qapi-schema.json | 19 +++++++++++
> >  3 files changed, 115 insertions(+)
> > 
> 
> > +++ b/qga/qapi-schema.json
> > @@ -738,3 +738,22 @@
> >  ##
> >  { 'command': 'guest-get-fsinfo',
> >    'returns': ['GuestFilesystemInfo'] }
> > +
> > +##
> > +# @guest-set-admin-password
> > +#
> > +# @crypted: true if password is already crypt()d, false if raw
> > +# @password: the new password entry
> > +#
> > +# If the @crypted flag is true, it is the callers responsibility
> 
> s/callers/caller's/
> 
> > +# to ensure the correct crypt() encryption scheme is used. This
> > +# command does not attempt to interpret or report on the encryption
> > +# scheme. Refer to the documentation of the guest operating system
> > +# in question to determine what is supported.
> > +#
> > +# Returns: Nothing on success.
> > +#
> > +# Since 2.3
> > +##
> > +{ 'command': 'guest-set-admin-password',
> > +  'data': { 'crypted': 'bool', 'password': 'str' } }
> > 
> 
> Normally, 'password':'str' means we are passing UTF8 JSON.  But what if
> the desired password is NOT valid UTF8, but still valid to the end user
> (for example, a user that intentionally wants a Latin1 encoded password
> that uses 8-bit characters)?  In other interfaces, we've allowed an enum
> that specifies whether a raw data string is 'utf8' or 'base64' encoded;
> should we have such a parameter here?

IMHO, QEMU itself needs to avoid interpreting the password at all and
just pass the raw bytes through to the operating system specific
command as-is. ie we should be 8-bit pure in what we accept. This
probably argues for unconditionally using base64 encoded data for
the parameter.


Regards,
Daniel
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