Adds a data-driven test that loads testdata/nodeattrs_results/*.hujson
and diffs the captured SaaS-rendered netmaps against headscale's
compileNodeAttrs output. Each capture is one scenario the SaaS
control plane has rendered against the same policy headscale is asked
to compile -- the test enforces shape parity per node.
tailnet_state_caps.go enumerates the caps SaaS emits where headscale
has no equivalent concept yet (user-role admin/owner, tailnet lock,
services host, app connectors, internal magicsock and SSH tuning,
tailnet-state metadata) plus the always-on baseline (admin, ssh,
file-sharing) and the taildrive pair. stripUnmodelledTailnetStateCaps
filters both sides of cmp.Diff so the comparison focuses on the
policy-driven caps. PeerCapMap encodes which caps the Tailscale
client reads from the peer view (suggest-exit-node when exit routes
are approved, etc.) for use by the mapper.
testcapture switches to typed tailcfg/netmap/filtertype/apitype
values so schema drift between the capture tool and headscale
becomes a compile error rather than a silent test failure. Existing
compat suites (acl, grants, routes, ssh, issue_3212) move to the
typed shape.
The 53 SelfNode netmap captures and the 7 anonymizer-corrupted
suggest-charmander -> suggest-exit-node restorations in
routes_results / issue_3212 ride along.
compileFilterRules skipped autogroup:internet destinations to keep them
out of the wire-format PacketFilter, but those same compiled rules are
the source of pm.matchers — and Node.CanAccess relies on a matcher whose
DestsIsTheInternet covers the public internet to surface exit-node peers
to ACL sources. With the skip in place no such matcher existed, exit
nodes silently dropped out of the source's peer list, and the docs'
exit-node walkthrough stopped working: `tailscale exit-node list`
returned "no exit nodes found" and `tailscale set --exit-node=<ip>`
returned "no node found in netmap with IP".
Drop the compile-time skip so autogroup:internet flows through normal
matcher derivation, and teach ReduceFilterRules to keep the resulting
client packet-filter rule on exit-route advertisers — Tailscale SaaS
sends those rules to exit nodes so the kernel filter accepts traffic
forwarded by autogroup:internet sources.
Verified against a live tailnet on 2026-04-28 via tscap; the b17/b18
captures land under testdata/issue_3212/ as a regression guard. The
captures are isolated from testdata/routes_results/ because the broader
TestRoutesCompat machinery assumes a CIDR-prefix wire format that
differs from the IPSet-range form SaaS emits for autogroup:internet —
aligning that wire format is tracked separately.
Fixes#3212
