Will all SIDs fit into |SECURITY_MAX_SID_SIZE| bytes ? / was: Re: Switching groups with newgrp - how to get the new group with |GetTokenInformation()| ?

Roland Mainz roland.mainz@nrubsig.org
Sat Feb 24 14:38:05 GMT 2024


On Thu, Feb 22, 2024 at 8:11 PM Corinna Vinschen via Cygwin
<cygwin@cygwin.com> wrote:
> On Feb 22 18:38, Roland Mainz via Cygwin wrote:
> > If I switch the current user's group with /usr/bin/newgrp, how can a
> > (native) Win32 process use
> > |GetTokenInformation(GetCurrentThreadToken(), ...)| to find out which
> > group is the new "current group" (e.g. which |TokenInformationClass|
> > should I use) ?
>
>   PSID sidbuf = (PSID) alloca (SECURITY_MAX_SID_SIZE);
[snip]

Win32/NT API question: All known SIDs will fit into
|SECURITY_MAX_SID_SIZE| bytes, right ? I'm asking because right now
the ms-nfs41-client code assumes that all SIDs use a variable amount
of memory, and we always have to ask the Win32/NT API about the number
of bytes to allocate. If |SECURITY_MAX_SID_SIZE| is the global maximum
limit for all Windows versions, then we could simplify the code a
lot...

----

Bye,
Roland
-- 
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