Add LoadDLLfuncEx statements for AllocateLocallyUniqueId@4,
DuplicateTokenEx@24, LsaNtStatusToWinError@4,
LsaDeregisterLogonProcess@4, LsaFreeReturnBuffer@4,
LsaLogonUser@56, LsaLookupAuthenticationPackage@12,
LsaRegisterLogonProcess@12,
* environ.cc: Add extern declaration for `subauth_id'.
(subauth_id_init): New function for setting `subauth_id'.
(struct parse_thing): Add entry for `subauth_id'.
* fork.cc (fork_parent): Call `RevertToSelf' and
`ImpersonateLoggedOnUser' instead of `seteuid'.
* security.cc: Define global variable `subauth_id'.
(extract_nt_dom_user): New function.
(cygwin_logon_user): Call `extract_nt_dom_user' now.
(str2lsa): New static function.
(str2buf2lsa): Ditto.
(str2buf2uni): Ditto.
(subauth): Ditto.
* security.h: Add prototype for `subauth'.
* spawn.cc (spawn_guts): Use cygheap->user.token only if impersonated.
Use `cygsid' type. Remove impersonation before allowing access to
workstation/desktop to everyone. Call `RevertToSelf' and
`ImpersonateLoggedOnUser' instead of `seteuid'.
* syscalls.cc (seteuid): Rearranged to allow using subauthentication
to retrieve user tokens when needed.