Restrict outbound clipboard

[jaroslaw-osmanski]

This patch adds configuration option to xrdp-chansrv that turns copying from the session to clipboard.

[metalefty]

Awesome! Good work!

[metalefty]

Existing codes use environment variable to pass config parameter. For example, CHANSRV_LOG_PATH.
Of course environment variable is not the best way but consider using environment variable or let's discuss.

[jaroslaw-osmanski]

Should env be the only way of setting restriction on the clipboard or additional method? In my opinion config is less surprising. @metalefty

[metalefty]

One unacceptable point is chansrv is opening and reading sesman's config file sesman.ini. Please don't do that. Then you'll see how clipboard restriction flag should be passed sesman to chansrv.

[metalefty]

Adding RestrictOutboundClipboard parameter to sesman.ini is OK. It's not surprising at all. The parameter must be fetched by sesman because it is sesman.ini.

[jaroslaw-osmanski]

OK. Sesman gathers info from sesman.ini and then passes information about restriction to chansrv, right?

[jaroslaw-osmanski]

chnsrv is already reading sesman.ini here: https://github.com/neutrinolabs/xrdp/blob/devel/sesman/chansrv/chansrv.c#L1639
So it is config.c that shouldn't be used?

[metalefty]

Indeed. That should be fixed but not at this time. I'll change it later.

I'm thinking of this. Similar thing is done as CHANSRV_LOG_LEVEL to set chansrv log level. The difference is setting environment variable directly or via config parameter.

sesman

1. sesman read if RestrictOutboundClipboard is on/off
2. sesman sets env var something like RESTRICT_OUTBOUND_CLIPBOARD to something like 1, yes, true
3. start chansrv with that env var

chansrv

3. read the env var at startup
4. if set to 1, restrict outbound clipboard

[jaroslaw-osmanski]

@metalefty Can I do something more to improve the code?

[metalefty]

@jaroslaw-osmanski Give me some time to test.

[metalefty]

I commented on some style & format issues but logic looks OK. After some test, I'll merge. I'd appreciate if you fix style & format before I merge.

[jaroslaw-osmanski]

@metalefty Fixed style and format

[metalefty]

I'm testing this today and will be merged shortly. Sorry for the delay and thank you very much for your work!

[metalefty]

Tested. Clipboard text/image/file LGTM.

[black1220]

Can I only pass text copy&paste and limit file transfer ?