This first bit of code aims to add a "map" to the packet functionality
that is able to translate to and from "method strings" to "command ids".
IDs are sent across the wire, and they're now integers. This removes the
need for the strings to be present in things like native meterp, and
hence makes things a little less obvious on the wire, and way less
obvious on disk/in the payload.
Given that we need this functionality in other Meterpreters to support
the removal of strings, some code has been added that can generate
source files for Python, C# and C. This code might move, but for now
it's at least in a spot where it's used the most.
This gives us the ability to force TLV encryption if for some reason
it's not already in place, and it means we can renegotiate a new key on
the fly if we want to.
Since OpenSSL is no longer packages with meterpreter, and transport
secrecy is handled at L7, the SSL cons name doesn't apply anymore.
Rename METERPRETER_TRANSPORT_SSL to METERPRETER_TRANSPORT_TCP for
consistency with wire-level implementation.
This changes the encryption flags on the meterpreter session so that
it's 32 bits (and hence changes the packet header). This also supports
the idea that sessions may use encryption that isn't AES256, so the
flags field will ultimately indicate that. A type flag has been added so
that MSF knows the type that should be done on the wire.
At some point soon we'll add something that makes sure that the packet
encryption type always matches the encryption type expected in MSF, this
will hopefully avoid the risk of having packets injected into the stream
by external entities.
The Session GUID will identify active sessions, and is the beginning of
work that will allow for tracking of sessions that have come back alive
after failing or switching transports.
h00die