Add stateless=true metadata option to UDP listener/handler for raw
datagram forwarding without per-client session tracking, similar to
NGINX Stream Module behavior.
- udp.NewListener: add Stateless field to ListenConfig; branch in
NewListener/Accept to skip connPool/listenLoop when stateless
- datagramConn: lightweight net.Conn+PacketConn wrapping a single
UDP datagram — no channels, mutexes, or pool logic
- forward handler: add handleRawDatagram for single request-response
cycle; extract dialTarget to share hop selection/dial/proxyproto
preamble with handleRawForwarding
Usage: gost -L "udp://:10000/127.0.0.1:2000?stateless=true"
The readTimeout field (default 15s) was being applied via xnet.Pipe to both
directions of a bidirectional proxy connection. During asymmetric transfers
(e.g. HTTP file download), the direction reading from the tunnel sees no
data after the initial request is forwarded, causing SetReadDeadline to fire
after 15s and abort the entire transfer.
Fix: add a separate idleTimeout field (default 0=disabled) to the metadata
structs in both forward/local and forward/remote handlers, and switch
xnet.Pipe to use idleTimeout instead of readTimeout. The readTimeout field
now only applies to the initial protocol sniffing/handshake phase.
Also document readTimeout vs idleTimeout semantics across all 24 locations
in the x/ module where these timeouts appear:
- readTimeout: handshake sniffing deadline (handlers), upstream response
header timeout (http.Transport), or transport-level read deadline
- idleTimeout: idle read deadline per Pipe direction (0=disabled)
- ReadTimeout on Sniffer/SnifferBuilder: upstream response header/TLS
handshake read timeout during sniffing
Extract Handle into handleRawForwarding, handleSniffedProtocol, SnifferBuilder,
newRecorderObject, and checkRateLimit across forward.go, sniffing.go, and
util.go. Replace redundant x509.ParseCertificate with tlsCert.Leaf (already
populated by tls.LoadX509KeyPair since Go 1.23).
ginuerzh