When the client shuts down its sending side, sockmap() shuts down the
server's in turn, and once the server has answered and closed, poll()
reports a hang-up on its socket. A socket sockmap() had nothing to ask
of at that moment, its buffer being full for a slow client, was still
polled, and a hang-up there ended both directions: whatever of the
answer was still unread in the kernel was dropped and the client got an
end of stream in the middle of it, megabytes short with large answers.
A hang-up on such a socket now only marks it: what is left is read
once the buffer has room, up to the end of the stream as usual. Errors
still end the connection. Since poll() reports a hang-up whatever is
asked, the socket is left out of poll() while nothing is asked of it.
The same holds for the client's side, for an upload cut short after the
server half-closes.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
tcppm and udppm forward a port each, so test both directions of each: a
request through the TCP mapper reaching its target, a datagram through the
UDP one coming back answered, and a mapper whose rules deny the client
answering nothing.
tlspr takes its destination from the name in the handshake, so point that
name at 127.0.0.1 with nsrecord and give the certificate the same name: the
name then both chooses where the request goes and is what the client checks.
dnspr answers from its cache, including the documented 0.0.0.0 record, which
is handed out as an address rather than withheld.
auto is asked to serve an HTTP proxy request, SOCKS4, SOCKS5 and a TLS
handshake on one port, and to make nothing of a request that is none of
them. Its protocols reach different places, so there are two origins.
The SOCKS UDP association was only checked for the port it binds. Send
datagrams through it as well, large and small, and check a second
association gets its own port - and that one bound inside an intport range
still relays.
A UDP service has no socket to connect to, so readiness is found by asking
until it answers rather than racing it.
