decodeCappedValues is documented to count JSON values, but it also
counted object keys and closing brackets, so a node's GUID-keyed online
and IP trees reached the cap at roughly half the stated number of
values, and the master then refused the whole report rather than the
excess.
Keys and closing brackets no longer count; every value, nested ones
included, still does.
pushClientTraffics decoded the pushed list whole, and each "{}" became a
full traffic row, so a body under the size cap could cost the panel
close to a gigabyte. The list is now decoded entry by entry and refused
past 262144 entries. The capped decoder the node runtime already used
moves to json_util so both share it.
Node responses are untrusted input on the master, and a few shapes still
cost it without bound under the 64 MiB body cap:
- a success=false message became an error (logged, stored as lastError)
in full; it is now cut to the 8 KiB the non-200 diagnostic already uses;
- each "{}" of a reported list decodes into a whole struct, so lists are
now decoded entry by entry with per-endpoint caps (1024 descendants,
65536 inbounds and host groups, 1M client-IP rows), and the GUID-keyed
trees and maps are capped at 1M values;
- a TLS handshake the node never answers kept a socket and goroutines
alive forever, since the transport keeps dialing for its pool after the
request gives up; node transports now give up after 10 s.