MatchFromFilterRule only read DstPorts[].IP into the destination
IPSet. Cap-grant-only filter rules (e.g. tailscale.com/cap/relay)
carry their destinations in CapGrant[].Dsts, so the derived matchers
had empty dest sets and BuildPeerMap / ReduceNodes never exposed the
cap target to its source nodes. Without a companion IP-level grant
the relay node stayed invisible, so clients never tried to use it
and connections sat on DERP.
Union CapGrant[].Dsts into the destination IPSet alongside DstPorts.
Restores peer-visibility for any cap-grant-only relationship; the
peer-relay flow is the most visible instance.
Fixes#3256
DestsIsTheInternet now reports the internet when either family's /0
is contained (0.0.0.0/0 or ::/0), matching what operators expect when
they write the /0 directly. Also documents MatchFromStrings fail-open.
Updates #3157
This is a massive commit that restructures the code into modules:
db/
All functions related to modifying the Database
types/
All type definitions and methods that can be exclusivly used on
these types without dependencies
policy/
All Policy related code, now without dependencies on the Database.
policy/matcher/
Dedicated code to match machines in a list of FilterRules
Signed-off-by: Kristoffer Dalby <kristoffer@tailscale.com>
