Powershell::Script includes a random generator (@rig) which can
produce non repeating randomized identifiers to be used as var
names within the PSH code.
Unwrap script handling in powershell env stager to instantate a
method-local Powershell::Script object and access its :rig to
generate identifiers.
Initial check logic would compress any script, even those which
would not need it since an uncompressed script fitting the buffer
would likely fit compressed (unless its uncompressable and the
decoder stub overflows). Ensure that compression occurs only when
a compressed script would fit while the uncompressed one does not.
Replace variable names with generated strings to increase entropy.
Add compression test for stager to determine if a compressed PSH
script will fit into the allowed space. If so, compress and exec
without staging.
Add variable name cleanup to stager mechanism - Remove-Variable
with -ErrorAction SilentlyContinue is called on each stager var
name after the stager executes.
TODO: Update method documentation
Conflicts:
lib/msf/core/post/windows/powershell.rb
Rename upload_script_via_psh to stage_psh_env within post PSH lib.
Perform the same rename within load_script post module.
Sync critical functionality from Rex and Msf namespaces dealing
with encoding and processing of powershell script for exploit
or post namespaces.
Import Post module. Primarily adds a psh_exec method which will be
replaced in the next PR with @benpturner's work integrated into
the Post module namespace.
Provide a sample metasploit windows post module to show the
execution pipeline - entire subs process can be removed and the
module reduced to a psh_exec(datastore['SCRIPT']).
This commit is designed to provide sync between the SVIT fork and
upstream. Pending commits to be based on this work will provide
access to .NET compiler in the Post namespace to be used for
dynamic persistent payload creation on target and the import of
@benpturner's work.
Spencer McIntyre