TLS13-C9: assert the vendored root blob instead of trusting it - #1288
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The blob is the guest's only source of trust. C8 shipped it generated but unasserted — a truncation or a stray byte would have produced a silently empty store on the guest, and an empty store fails closed in a way that looks exactly like a chain-validation bug. The test walks the framing: every byte is consumed by a length-prefixed DER certificate, each anchor parses as a CA with the expected subject CN, each loads into the same TrustStore type the client validates against, the version string round-trips, and the byte count is exact (no trailing slack). Also generated by emit_vendored_roots.py, so the test regenerates with the blob rather than drifting from it. Evidence: zig build test -> 198/198 steps, 3585/3585 tests (was 3572) zig build -> FETCHS.BIN still converts
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Follow-up to #1286 (C8). The vendored root blob is the guest's only source of trust, and C8 shipped it generated but unasserted.
A truncation or a stray byte would produce a silently empty store on the guest — which fails closed in a way indistinguishable from a chain-validation bug. That is exactly the class of failure that costs a day to find, so it is now a test instead.
The test walks the framing: every byte consumed by a length-prefixed DER certificate, each anchor parses as a CA with the expected subject CN, each loads into the same
TrustStoretype the client validates against, the version string round-trips, and the byte count is exact.Emitted by
emit_vendored_roots.py, so the test regenerates with the blob rather than drifting from it.