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Posted to dev@guacamole.apache.org by Amarjeet Singh <am...@gmail.com> on 2018/03/01 03:07:09 UTC
Re: Clipboard Redirection in FreeRDP
I have already added clipboard_enable falg in rdp_settings.h and
rdp_settings.c and parse the value of this flag.
On the basis of this flag I have loaded the cliprdr plugin and
clipboard_handler.
I have to pass this flag to FreeRDP rdp_settings structure as there is a
varaible RedirectClipboard as per FreeRDP Manual for latest by version.
I have also handled the events of cliprdr on the basis of this flag.
Only thing left is to push the settings to FreeRDP.
On Mar 1, 2018 1:57 AM, "Mike Jumper" <mi...@guac-dev.org> wrote:
On Wed, Feb 28, 2018 at 1:01 AM, Amarjeet Singh <am...@gmail.com>
wrote:
> Hi Team,
>
> I am working on enabling and disabling clipboard.
>
> I went through *FreeRDP Manual* from which I found the following
variable
> in rdpSettings structure which is as follows:-
>
As far as disabling clipboard access within Guacamole is concerned, simply
requesting FreeRDP to not use clipboard would be the RDP version of
genetically engineering your dinosaurs to be female. You should instead
absolutely guarantee that clipboard will not function by controlling things
at the Guacamole protocol level, ignoring received clipboard data from the
client (by not providing a handler for that data), and not forwarding
clipboard data to the client even if received from the RDP server.
Recall that, for clipboard data to be received/sent by the client, a
"clipboard" instruction is used to establish the stream of data:
http://guacamole.apache.org/doc/gug/protocol-reference.
html#clipboard-instruction
To ensure this does not actually have an effect, you would want to make
handling of that instruction conditional depending on some enable/disable
flag, and disable sending of clipboard data to connected clients while that
flag is sent. Conditional handling of instructions is already used for
implementing the "read-only" parameter, and is really what would be
required here:
https://github.com/apache/guacamole-server/blob/
bc5b01d4d8ab0c3c89a08007316d33012261f6b3/src/protocols/rdp/user.c#L97-L114
Besides being reliable, this has the added bonus that the fact that
clipboard streams cannot be established is automatically exposed to the
client through "ack" instructions, and implementations can choose to handle
this by adjusting the interface accordingly, warning the user that
clipboard has been disabled, etc.
- Mike
Re: Clipboard Redirection in FreeRDP
Posted by Mike Jumper <mi...@guac-dev.org>.
On Feb 28, 2018 19:13, "Amarjeet Singh" <am...@gmail.com> wrote:
Though it's working but I have to handle and send the ack that clipboard is
disabled if request comes from client to server.
This will happen automatically if clipboard_handler is left as NULL.
- Mike
Re: Clipboard Redirection in FreeRDP
Posted by Amarjeet Singh <am...@gmail.com>.
I will contribute asap.
I have to setup the environment and need to learn how ( Pull request and
all that stuff ) it works as I haven't done in the past.
Facing issues in the upstream-branch ( when I use git fetch upstream and
merge code in my master branch and try to build the war file it fails. ) I
haven't done any changes in the master branch. I was trying to follow the
process of GIT PULL.
I will look into it and and try to fix it asap.
Regards,
Amarjeet Singh
On Thu, Mar 15, 2018 at 12:59 PM, Mike Jumper <mi...@guac-dev.org>
wrote:
> Amarjeet, is this something you're looking to contribute?
>
> - Mike
>
>
> On Wed, Feb 28, 2018 at 7:38 PM, Amarjeet Singh <am...@gmail.com>
> wrote:
>
> > Thanks Mike. I will try again to find the flag in source of FreeRDP (
> > different versions ).
> >
> >
> > On Mar 1, 2018 9:03 AM, "Mike Jumper" <mi...@guac-dev.org> wrote:
> >
> > > You will need to go through the FreeRDP source to determine what that
> > flag
> > > does, and then look through the source of other versions to see what
> has
> > > the same effect, assuming that flag is not simply a place for the
> > xfreerdp
> > > to store a command-line parameter.
> > >
> > > - Mike
> > >
> > > On Feb 28, 2018 19:22, "Amarjeet Singh" <am...@gmail.com> wrote:
> > >
> > > Likewise Guacamole used device_redirection for LEGACY_SETTINGS else
> > > DeviceRedirection, I have to implement it for clipboard while pushing
> > > settings to FreeRDP rdp_settings structure.
> > > I do know RedirectClipboard but not sure of LEGACY_SETTINGS of
> > rdp_settings
> > > structure.
> > > @ Mike I tried to find that in different versions of FreRDP but didn't
> > find
> > > anything. RedirectCipboard is in the version of 1.0.2.
> > >
> > > On Mar 1, 2018 8:43 AM, "Amarjeet Singh" <am...@gmail.com> wrote:
> > >
> > > > Though it's working but I have to handle and send the ack that
> > clipboard
> > > > is disabled if request comes from client to server.
> > > >
> > > > On Mar 1, 2018 8:37 AM, "Amarjeet Singh" <am...@gmail.com>
> wrote:
> > > >
> > > >> I have already added clipboard_enable falg in rdp_settings.h and
> > > >> rdp_settings.c and parse the value of this flag.
> > > >> On the basis of this flag I have loaded the cliprdr plugin and
> > > >> clipboard_handler.
> > > >> I have to pass this flag to FreeRDP rdp_settings structure as there
> > is a
> > > >> varaible RedirectClipboard as per FreeRDP Manual for latest by
> > version.
> > > >> I have also handled the events of cliprdr on the basis of this flag.
> > > >>
> > > >> Only thing left is to push the settings to FreeRDP.
> > > >>
> > > >> On Mar 1, 2018 1:57 AM, "Mike Jumper" <mi...@guac-dev.org>
> > wrote:
> > > >>
> > > >> On Wed, Feb 28, 2018 at 1:01 AM, Amarjeet Singh <
> amarjeetxc@gmail.com
> > >
> > > >> wrote:
> > > >>
> > > >> > Hi Team,
> > > >> >
> > > >> > I am working on enabling and disabling clipboard.
> > > >> >
> > > >> > I went through *FreeRDP Manual* from which I found the following
> > > >> variable
> > > >> > in rdpSettings structure which is as follows:-
> > > >> >
> > > >>
> > > >> As far as disabling clipboard access within Guacamole is concerned,
> > > simply
> > > >> requesting FreeRDP to not use clipboard would be the RDP version of
> > > >> genetically engineering your dinosaurs to be female. You should
> > instead
> > > >> absolutely guarantee that clipboard will not function by controlling
> > > >> things
> > > >> at the Guacamole protocol level, ignoring received clipboard data
> from
> > > the
> > > >> client (by not providing a handler for that data), and not
> forwarding
> > > >> clipboard data to the client even if received from the RDP server.
> > > >>
> > > >> Recall that, for clipboard data to be received/sent by the client, a
> > > >> "clipboard" instruction is used to establish the stream of data:
> > > >>
> > > >> http://guacamole.apache.org/doc/gug/protocol-reference.html#
> > > >> clipboard-instruction
> > > >>
> > > >> To ensure this does not actually have an effect, you would want to
> > make
> > > >> handling of that instruction conditional depending on some
> > > enable/disable
> > > >> flag, and disable sending of clipboard data to connected clients
> while
> > > >> that
> > > >> flag is sent. Conditional handling of instructions is already used
> for
> > > >> implementing the "read-only" parameter, and is really what would be
> > > >> required here:
> > > >>
> > > >> https://github.com/apache/guacamole-server/blob/bc5b01d4d8ab
> > > >> 0c3c89a08007316d33012261f6b3/src/protocols/rdp/user.c#L97-L114
> > > >>
> > > >> Besides being reliable, this has the added bonus that the fact that
> > > >> clipboard streams cannot be established is automatically exposed to
> > the
> > > >> client through "ack" instructions, and implementations can choose to
> > > >> handle
> > > >> this by adjusting the interface accordingly, warning the user that
> > > >> clipboard has been disabled, etc.
> > > >>
> > > >> - Mike
> > > >>
> > > >>
> > > >>
> > >
> >
>
Re: Clipboard Redirection in FreeRDP
Posted by Mike Jumper <mi...@guac-dev.org>.
Amarjeet, is this something you're looking to contribute?
- Mike
On Wed, Feb 28, 2018 at 7:38 PM, Amarjeet Singh <am...@gmail.com>
wrote:
> Thanks Mike. I will try again to find the flag in source of FreeRDP (
> different versions ).
>
>
> On Mar 1, 2018 9:03 AM, "Mike Jumper" <mi...@guac-dev.org> wrote:
>
> > You will need to go through the FreeRDP source to determine what that
> flag
> > does, and then look through the source of other versions to see what has
> > the same effect, assuming that flag is not simply a place for the
> xfreerdp
> > to store a command-line parameter.
> >
> > - Mike
> >
> > On Feb 28, 2018 19:22, "Amarjeet Singh" <am...@gmail.com> wrote:
> >
> > Likewise Guacamole used device_redirection for LEGACY_SETTINGS else
> > DeviceRedirection, I have to implement it for clipboard while pushing
> > settings to FreeRDP rdp_settings structure.
> > I do know RedirectClipboard but not sure of LEGACY_SETTINGS of
> rdp_settings
> > structure.
> > @ Mike I tried to find that in different versions of FreRDP but didn't
> find
> > anything. RedirectCipboard is in the version of 1.0.2.
> >
> > On Mar 1, 2018 8:43 AM, "Amarjeet Singh" <am...@gmail.com> wrote:
> >
> > > Though it's working but I have to handle and send the ack that
> clipboard
> > > is disabled if request comes from client to server.
> > >
> > > On Mar 1, 2018 8:37 AM, "Amarjeet Singh" <am...@gmail.com> wrote:
> > >
> > >> I have already added clipboard_enable falg in rdp_settings.h and
> > >> rdp_settings.c and parse the value of this flag.
> > >> On the basis of this flag I have loaded the cliprdr plugin and
> > >> clipboard_handler.
> > >> I have to pass this flag to FreeRDP rdp_settings structure as there
> is a
> > >> varaible RedirectClipboard as per FreeRDP Manual for latest by
> version.
> > >> I have also handled the events of cliprdr on the basis of this flag.
> > >>
> > >> Only thing left is to push the settings to FreeRDP.
> > >>
> > >> On Mar 1, 2018 1:57 AM, "Mike Jumper" <mi...@guac-dev.org>
> wrote:
> > >>
> > >> On Wed, Feb 28, 2018 at 1:01 AM, Amarjeet Singh <amarjeetxc@gmail.com
> >
> > >> wrote:
> > >>
> > >> > Hi Team,
> > >> >
> > >> > I am working on enabling and disabling clipboard.
> > >> >
> > >> > I went through *FreeRDP Manual* from which I found the following
> > >> variable
> > >> > in rdpSettings structure which is as follows:-
> > >> >
> > >>
> > >> As far as disabling clipboard access within Guacamole is concerned,
> > simply
> > >> requesting FreeRDP to not use clipboard would be the RDP version of
> > >> genetically engineering your dinosaurs to be female. You should
> instead
> > >> absolutely guarantee that clipboard will not function by controlling
> > >> things
> > >> at the Guacamole protocol level, ignoring received clipboard data from
> > the
> > >> client (by not providing a handler for that data), and not forwarding
> > >> clipboard data to the client even if received from the RDP server.
> > >>
> > >> Recall that, for clipboard data to be received/sent by the client, a
> > >> "clipboard" instruction is used to establish the stream of data:
> > >>
> > >> http://guacamole.apache.org/doc/gug/protocol-reference.html#
> > >> clipboard-instruction
> > >>
> > >> To ensure this does not actually have an effect, you would want to
> make
> > >> handling of that instruction conditional depending on some
> > enable/disable
> > >> flag, and disable sending of clipboard data to connected clients while
> > >> that
> > >> flag is sent. Conditional handling of instructions is already used for
> > >> implementing the "read-only" parameter, and is really what would be
> > >> required here:
> > >>
> > >> https://github.com/apache/guacamole-server/blob/bc5b01d4d8ab
> > >> 0c3c89a08007316d33012261f6b3/src/protocols/rdp/user.c#L97-L114
> > >>
> > >> Besides being reliable, this has the added bonus that the fact that
> > >> clipboard streams cannot be established is automatically exposed to
> the
> > >> client through "ack" instructions, and implementations can choose to
> > >> handle
> > >> this by adjusting the interface accordingly, warning the user that
> > >> clipboard has been disabled, etc.
> > >>
> > >> - Mike
> > >>
> > >>
> > >>
> >
>
Re: Clipboard Redirection in FreeRDP
Posted by Amarjeet Singh <am...@gmail.com>.
Thanks Mike. I will try again to find the flag in source of FreeRDP (
different versions ).
On Mar 1, 2018 9:03 AM, "Mike Jumper" <mi...@guac-dev.org> wrote:
> You will need to go through the FreeRDP source to determine what that flag
> does, and then look through the source of other versions to see what has
> the same effect, assuming that flag is not simply a place for the xfreerdp
> to store a command-line parameter.
>
> - Mike
>
> On Feb 28, 2018 19:22, "Amarjeet Singh" <am...@gmail.com> wrote:
>
> Likewise Guacamole used device_redirection for LEGACY_SETTINGS else
> DeviceRedirection, I have to implement it for clipboard while pushing
> settings to FreeRDP rdp_settings structure.
> I do know RedirectClipboard but not sure of LEGACY_SETTINGS of rdp_settings
> structure.
> @ Mike I tried to find that in different versions of FreRDP but didn't find
> anything. RedirectCipboard is in the version of 1.0.2.
>
> On Mar 1, 2018 8:43 AM, "Amarjeet Singh" <am...@gmail.com> wrote:
>
> > Though it's working but I have to handle and send the ack that clipboard
> > is disabled if request comes from client to server.
> >
> > On Mar 1, 2018 8:37 AM, "Amarjeet Singh" <am...@gmail.com> wrote:
> >
> >> I have already added clipboard_enable falg in rdp_settings.h and
> >> rdp_settings.c and parse the value of this flag.
> >> On the basis of this flag I have loaded the cliprdr plugin and
> >> clipboard_handler.
> >> I have to pass this flag to FreeRDP rdp_settings structure as there is a
> >> varaible RedirectClipboard as per FreeRDP Manual for latest by version.
> >> I have also handled the events of cliprdr on the basis of this flag.
> >>
> >> Only thing left is to push the settings to FreeRDP.
> >>
> >> On Mar 1, 2018 1:57 AM, "Mike Jumper" <mi...@guac-dev.org> wrote:
> >>
> >> On Wed, Feb 28, 2018 at 1:01 AM, Amarjeet Singh <am...@gmail.com>
> >> wrote:
> >>
> >> > Hi Team,
> >> >
> >> > I am working on enabling and disabling clipboard.
> >> >
> >> > I went through *FreeRDP Manual* from which I found the following
> >> variable
> >> > in rdpSettings structure which is as follows:-
> >> >
> >>
> >> As far as disabling clipboard access within Guacamole is concerned,
> simply
> >> requesting FreeRDP to not use clipboard would be the RDP version of
> >> genetically engineering your dinosaurs to be female. You should instead
> >> absolutely guarantee that clipboard will not function by controlling
> >> things
> >> at the Guacamole protocol level, ignoring received clipboard data from
> the
> >> client (by not providing a handler for that data), and not forwarding
> >> clipboard data to the client even if received from the RDP server.
> >>
> >> Recall that, for clipboard data to be received/sent by the client, a
> >> "clipboard" instruction is used to establish the stream of data:
> >>
> >> http://guacamole.apache.org/doc/gug/protocol-reference.html#
> >> clipboard-instruction
> >>
> >> To ensure this does not actually have an effect, you would want to make
> >> handling of that instruction conditional depending on some
> enable/disable
> >> flag, and disable sending of clipboard data to connected clients while
> >> that
> >> flag is sent. Conditional handling of instructions is already used for
> >> implementing the "read-only" parameter, and is really what would be
> >> required here:
> >>
> >> https://github.com/apache/guacamole-server/blob/bc5b01d4d8ab
> >> 0c3c89a08007316d33012261f6b3/src/protocols/rdp/user.c#L97-L114
> >>
> >> Besides being reliable, this has the added bonus that the fact that
> >> clipboard streams cannot be established is automatically exposed to the
> >> client through "ack" instructions, and implementations can choose to
> >> handle
> >> this by adjusting the interface accordingly, warning the user that
> >> clipboard has been disabled, etc.
> >>
> >> - Mike
> >>
> >>
> >>
>
Re: Clipboard Redirection in FreeRDP
Posted by Mike Jumper <mi...@guac-dev.org>.
You will need to go through the FreeRDP source to determine what that flag
does, and then look through the source of other versions to see what has
the same effect, assuming that flag is not simply a place for the xfreerdp
to store a command-line parameter.
- Mike
On Feb 28, 2018 19:22, "Amarjeet Singh" <am...@gmail.com> wrote:
Likewise Guacamole used device_redirection for LEGACY_SETTINGS else
DeviceRedirection, I have to implement it for clipboard while pushing
settings to FreeRDP rdp_settings structure.
I do know RedirectClipboard but not sure of LEGACY_SETTINGS of rdp_settings
structure.
@ Mike I tried to find that in different versions of FreRDP but didn't find
anything. RedirectCipboard is in the version of 1.0.2.
On Mar 1, 2018 8:43 AM, "Amarjeet Singh" <am...@gmail.com> wrote:
> Though it's working but I have to handle and send the ack that clipboard
> is disabled if request comes from client to server.
>
> On Mar 1, 2018 8:37 AM, "Amarjeet Singh" <am...@gmail.com> wrote:
>
>> I have already added clipboard_enable falg in rdp_settings.h and
>> rdp_settings.c and parse the value of this flag.
>> On the basis of this flag I have loaded the cliprdr plugin and
>> clipboard_handler.
>> I have to pass this flag to FreeRDP rdp_settings structure as there is a
>> varaible RedirectClipboard as per FreeRDP Manual for latest by version.
>> I have also handled the events of cliprdr on the basis of this flag.
>>
>> Only thing left is to push the settings to FreeRDP.
>>
>> On Mar 1, 2018 1:57 AM, "Mike Jumper" <mi...@guac-dev.org> wrote:
>>
>> On Wed, Feb 28, 2018 at 1:01 AM, Amarjeet Singh <am...@gmail.com>
>> wrote:
>>
>> > Hi Team,
>> >
>> > I am working on enabling and disabling clipboard.
>> >
>> > I went through *FreeRDP Manual* from which I found the following
>> variable
>> > in rdpSettings structure which is as follows:-
>> >
>>
>> As far as disabling clipboard access within Guacamole is concerned,
simply
>> requesting FreeRDP to not use clipboard would be the RDP version of
>> genetically engineering your dinosaurs to be female. You should instead
>> absolutely guarantee that clipboard will not function by controlling
>> things
>> at the Guacamole protocol level, ignoring received clipboard data from
the
>> client (by not providing a handler for that data), and not forwarding
>> clipboard data to the client even if received from the RDP server.
>>
>> Recall that, for clipboard data to be received/sent by the client, a
>> "clipboard" instruction is used to establish the stream of data:
>>
>> http://guacamole.apache.org/doc/gug/protocol-reference.html#
>> clipboard-instruction
>>
>> To ensure this does not actually have an effect, you would want to make
>> handling of that instruction conditional depending on some enable/disable
>> flag, and disable sending of clipboard data to connected clients while
>> that
>> flag is sent. Conditional handling of instructions is already used for
>> implementing the "read-only" parameter, and is really what would be
>> required here:
>>
>> https://github.com/apache/guacamole-server/blob/bc5b01d4d8ab
>> 0c3c89a08007316d33012261f6b3/src/protocols/rdp/user.c#L97-L114
>>
>> Besides being reliable, this has the added bonus that the fact that
>> clipboard streams cannot be established is automatically exposed to the
>> client through "ack" instructions, and implementations can choose to
>> handle
>> this by adjusting the interface accordingly, warning the user that
>> clipboard has been disabled, etc.
>>
>> - Mike
>>
>>
>>
Re: Clipboard Redirection in FreeRDP
Posted by Amarjeet Singh <am...@gmail.com>.
Likewise Guacamole used device_redirection for LEGACY_SETTINGS else
DeviceRedirection, I have to implement it for clipboard while pushing
settings to FreeRDP rdp_settings structure.
I do know RedirectClipboard but not sure of LEGACY_SETTINGS of rdp_settings
structure.
@ Mike I tried to find that in different versions of FreRDP but didn't find
anything. RedirectCipboard is in the version of 1.0.2.
On Mar 1, 2018 8:43 AM, "Amarjeet Singh" <am...@gmail.com> wrote:
> Though it's working but I have to handle and send the ack that clipboard
> is disabled if request comes from client to server.
>
> On Mar 1, 2018 8:37 AM, "Amarjeet Singh" <am...@gmail.com> wrote:
>
>> I have already added clipboard_enable falg in rdp_settings.h and
>> rdp_settings.c and parse the value of this flag.
>> On the basis of this flag I have loaded the cliprdr plugin and
>> clipboard_handler.
>> I have to pass this flag to FreeRDP rdp_settings structure as there is a
>> varaible RedirectClipboard as per FreeRDP Manual for latest by version.
>> I have also handled the events of cliprdr on the basis of this flag.
>>
>> Only thing left is to push the settings to FreeRDP.
>>
>> On Mar 1, 2018 1:57 AM, "Mike Jumper" <mi...@guac-dev.org> wrote:
>>
>> On Wed, Feb 28, 2018 at 1:01 AM, Amarjeet Singh <am...@gmail.com>
>> wrote:
>>
>> > Hi Team,
>> >
>> > I am working on enabling and disabling clipboard.
>> >
>> > I went through *FreeRDP Manual* from which I found the following
>> variable
>> > in rdpSettings structure which is as follows:-
>> >
>>
>> As far as disabling clipboard access within Guacamole is concerned, simply
>> requesting FreeRDP to not use clipboard would be the RDP version of
>> genetically engineering your dinosaurs to be female. You should instead
>> absolutely guarantee that clipboard will not function by controlling
>> things
>> at the Guacamole protocol level, ignoring received clipboard data from the
>> client (by not providing a handler for that data), and not forwarding
>> clipboard data to the client even if received from the RDP server.
>>
>> Recall that, for clipboard data to be received/sent by the client, a
>> "clipboard" instruction is used to establish the stream of data:
>>
>> http://guacamole.apache.org/doc/gug/protocol-reference.html#
>> clipboard-instruction
>>
>> To ensure this does not actually have an effect, you would want to make
>> handling of that instruction conditional depending on some enable/disable
>> flag, and disable sending of clipboard data to connected clients while
>> that
>> flag is sent. Conditional handling of instructions is already used for
>> implementing the "read-only" parameter, and is really what would be
>> required here:
>>
>> https://github.com/apache/guacamole-server/blob/bc5b01d4d8ab
>> 0c3c89a08007316d33012261f6b3/src/protocols/rdp/user.c#L97-L114
>>
>> Besides being reliable, this has the added bonus that the fact that
>> clipboard streams cannot be established is automatically exposed to the
>> client through "ack" instructions, and implementations can choose to
>> handle
>> this by adjusting the interface accordingly, warning the user that
>> clipboard has been disabled, etc.
>>
>> - Mike
>>
>>
>>
Re: Clipboard Redirection in FreeRDP
Posted by Amarjeet Singh <am...@gmail.com>.
Though it's working but I have to handle and send the ack that clipboard is
disabled if request comes from client to server.
On Mar 1, 2018 8:37 AM, "Amarjeet Singh" <am...@gmail.com> wrote:
> I have already added clipboard_enable falg in rdp_settings.h and
> rdp_settings.c and parse the value of this flag.
> On the basis of this flag I have loaded the cliprdr plugin and
> clipboard_handler.
> I have to pass this flag to FreeRDP rdp_settings structure as there is a
> varaible RedirectClipboard as per FreeRDP Manual for latest by version.
> I have also handled the events of cliprdr on the basis of this flag.
>
> Only thing left is to push the settings to FreeRDP.
>
> On Mar 1, 2018 1:57 AM, "Mike Jumper" <mi...@guac-dev.org> wrote:
>
> On Wed, Feb 28, 2018 at 1:01 AM, Amarjeet Singh <am...@gmail.com>
> wrote:
>
> > Hi Team,
> >
> > I am working on enabling and disabling clipboard.
> >
> > I went through *FreeRDP Manual* from which I found the following
> variable
> > in rdpSettings structure which is as follows:-
> >
>
> As far as disabling clipboard access within Guacamole is concerned, simply
> requesting FreeRDP to not use clipboard would be the RDP version of
> genetically engineering your dinosaurs to be female. You should instead
> absolutely guarantee that clipboard will not function by controlling things
> at the Guacamole protocol level, ignoring received clipboard data from the
> client (by not providing a handler for that data), and not forwarding
> clipboard data to the client even if received from the RDP server.
>
> Recall that, for clipboard data to be received/sent by the client, a
> "clipboard" instruction is used to establish the stream of data:
>
> http://guacamole.apache.org/doc/gug/protocol-reference.html#
> clipboard-instruction
>
> To ensure this does not actually have an effect, you would want to make
> handling of that instruction conditional depending on some enable/disable
> flag, and disable sending of clipboard data to connected clients while that
> flag is sent. Conditional handling of instructions is already used for
> implementing the "read-only" parameter, and is really what would be
> required here:
>
> https://github.com/apache/guacamole-server/blob/bc5b01d4d8ab
> 0c3c89a08007316d33012261f6b3/src/protocols/rdp/user.c#L97-L114
>
> Besides being reliable, this has the added bonus that the fact that
> clipboard streams cannot be established is automatically exposed to the
> client through "ack" instructions, and implementations can choose to handle
> this by adjusting the interface accordingly, warning the user that
> clipboard has been disabled, etc.
>
> - Mike
>
>
>