* Restore the silently dropped embedded TUN routing rules
tun_singbox_rules declares "network": "udp" as a bare string, but
Rule4Sbox.network is a List<string>. System.Text.Json therefore throws on
the very first rule, and JsonUtils.Deserialize swallows it and returns
default. GenRouting only checks for null before AddRange, so the whole
embedded rule set is dropped without a trace.
Both rules it carries have thus never reached a generated config: the
NetBIOS/mDNS reject and the multicast reject. The mismatch predates the
sing-box 1.12 migration - the template has used the string form since the
rules file was introduced.
- declare network as an array so the template matches Rule4Sbox
* Drop traffic addressed to the TUN's own addresses
With auto_route the TUN steals the default route, so a packet whose
destination is the TUN interface's own address is handed to sing-box instead
of being looped back by the kernel. Routing then matches ip_is_private and
sends it to `direct`, whose interface is auto-detected as the TUN again, so
the packet is written straight back into the TUN and re-enters routing. The
loop never terminates and pins a CPU core.
Seen in the wild on macOS: a WebRTC client offered the TUN's own
fc00::172:18:0:1 ULA as an ICE candidate and the resulting STUN
connectivity checks sustained ~8k packets/s out of the interface at 800%
CPU, 21 GB written to the TUN over five hours - against 3 GB read, the
asymmetry that gives the loop away.
Nothing legitimate is addressed to those addresses, so reject them before
any outbound rule can match. Use method "drop" rather than the default
ICMP unreachable, whose destination would be the looping address itself.
- reject the TUN inbound's own addresses, taken from the generated inbound
so the two cannot drift apart
CoreManager.RunProcess decided sudo elevation from the live mutable
_config.TunModeItem.EnableTun while the launched config was generated
from the immutable CoreConfigContext snapshot. If the TUN state changed
while a reload was in flight, a core whose config contains a TUN
inbound could launch without elevation and die within the 100ms health
check ("Failed to run core"), with no stderr shown.
The elevation decision now follows context.IsTunEnabled /
preContext.IsTunEnabled, so the generated config and the launch mode
always agree. With legacy TUN protect, the sing-box pre-core hosting
TUN is elevated and the main core no longer runs as root needlessly.
sing-box requires realm.server_url as a full URL (https://host:port).
Bare host:port caused "missing host in realm server_url" on import.
Also forward stun_servers and clear ResolveRealm success message.
Fixes#9635
