headscale/hscontrol/policy
Kristoffer Dalby 5d502bfb88 types/node, mapper: strip own IPv4 from emission when node has disable-ipv4 cap
When a node carries the disable-ipv4 nodeAttr documented at
https://tailscale.com/docs/reference/troubleshooting/network-configuration/cgnat-conflicts,
SaaS stops sending the node's CGNAT IPv4 prefix in MapResponse. The
allocator keeps assigning IPv4 server-side; only the wire-shape
delivery is filtered. Subnet routes the node advertises -- including
IPv4 prefixes -- survive in AllowedIPs and PrimaryRoutes.

TailNode now drops Is4 prefixes from Addresses and from the node's
own /32 slot in AllowedIPs when selfPolicyCaps carries
disable-ipv4. Mapper.buildTailPeers passes each peer's policy
CapMap so the filter applies in viewer netmaps too; the CapMap
merge that follows is overwritten by PeerCapMap so only the address
filter survives on the peer path.

Two captures land in testdata/nodeattrs_results to anchor the
behaviour:

  - nodeattrs-attr-c15-disable-ipv4         (on tag:client)
  - nodeattrs-attr-c16-disable-ipv4-router  (on tag:router, which
    advertises 10.33.0.0/16, confirming subnet routes survive)
2026-05-13 14:22:30 +02:00
..
matcher policy/matcher: include CapGrant.Dsts in match destinations 2026-05-11 14:55:06 +01:00
policyutil policy: surface exit nodes via autogroup:internet (#3212) 2026-04-29 11:24:33 +01:00
v2 types/node, mapper: strip own IPv4 from emission when node has disable-ipv4 cap 2026-05-13 14:22:30 +02:00
pm.go policy/v2: parse, validate, and compile nodeAttrs 2026-05-13 14:22:30 +02:00
policy.go all: upgrade to Go 1.26rc2 and modernize codebase 2026-02-08 12:35:23 +01:00
policy_autoapprove_test.go policy/v2: refactor alias resolution to use ResolvedAddresses 2026-04-01 14:10:42 +01:00
policy_route_approval_test.go all: apply golangci-lint 2.9.0 fixes 2026-02-19 08:21:23 +01:00
policy_test.go policy: surface exit nodes via autogroup:internet (#3212) 2026-04-29 11:24:33 +01:00
route_approval_test.go all: upgrade to Go 1.26rc2 and modernize codebase 2026-02-08 12:35:23 +01:00