Integrate XS native Compartment support

[kriskowal]

What is the Problem Being Solved?

Support for XS native Compartments is currently in development in Endo endojs/endo#400. When that feature becomes available, we will need to make changes in Agoric SDK (targeting a particular upgrade.)

Description of the Design

We will need to adjust the SwingSet xsnap worker bootstrap to take advantage of the XS-specific variants of ses, @endo/static-module-record, and @endo/import-bundle to take advantage of this new feature, by using @endo/compartment-mapper/bundle.js to generate the bootstrap script and threading the appropriate “build tag” (xs) to cause it to select the correct alternate implementations.

Security Considerations

We will be more dependent on the correctness of XS. There will be some differences in expressivity of contracts that run under XS native compartments. There will be no censorship or evasive transforms. Typeof for references that are not in scope but overshadowing properties of the true global may change. Contracts will draw less from the meter.

Scaling Considerations

The chain will likely benefit from a performance boost from executing native modules instead of using our emulation layer. There may be a slight reduction in the size of the bootstrap bundle since it doesn’t need to entrain the lockdown and harden shims (but does entrain assert and compartment shims).

Test Plan

To be planned.

Upgrade Considerations

The new process will support both the SES shim Compartment and XS native Compartment

[mhofman]

AFAIK this will require an upgrade of XS, which is currently blocked on a plan to upgrade XS (see #6361), as well as a way to validate that such a newer version of XS is acceptable for our need (see #6929).

I am actually wondering here if we might be able to somehow validate a replay of old contract bundles running on a new version of XS with updated supervisor and lockdown bundles using the new XS based Compartment.

[aj-agoric]

Hello, as a part of xs planning the question arose is this ticket a portion or duplicate of #2480. @kriskowal thanks

[kriskowal]

The design proposed by this issue would satisfy the requirements of #2480. Please keep this issue.