SES 1.8.0 adds flexibility to Lockdown
Agoric has released ses version
1.8.0 with more
implementation-specific options to Hardened JavaScript’s lockdown() function
to improve ecosystem compatibility.
Regenerator Runtime Compatibility
Old versions of some npm packages used
regenerator to anticipate
JavaScript’s async functions before language support was ubiquitous.
These rely on
regenerator-runtime to
approximate the language feature.
However, in the few cases where a dependency on versions 0.10.5 to 0.13.7 of
regenerator-runtime persist, applications are incompatible with ses due to
misalignment of the global objects the runtime introduces and the environment
that Hardened JavaScript expects from the base language.
With SES 1.8.0, lockdown accepts a new option
legacyRegeneratorRuntimeTaming: 'unsafe-ignore' that repairs the intrinsics
shared by all compartments so that lockdown will allow them.
This remediation is not strictly safe because it converts
Iterator.prototype[Symbol.iterator] to a getter and setter, such that all
assignments to it are ignored.
This could cause code to procede on false assumption that it successfully
overwrote the Iterator.prototype[Symbol.iterator] instead of throwing an
error.
Error Trapping: Report
Starting with SES 1.8.0, the 'report' mode for the errorTrapping option to
lockdown will write errors to standard error with the new
"SES_UNCAUGHT_EXCEPTION: " prefix.
The 'report' mode is sometimes implied by 'platform', 'exit', or 'abort'.
This is intended to give valuable context to users of the system, especially
when an uncaught exception is not an Error object, and therefore its origin
may be hard to find in source code.
This is not likely to affect most systems built with SES, as stderr is
generally reserved for user-only messages.
If your SES system sends its stderr to a program which parses it, you may need
to adapt that program to be tolerant of the SES_UNCAUGHT_EXCEPTION: prefix.
Even for such programs, it is unlikely they are that sensitive to stderr
formatting.