I tried a transproxy and confirmed that there is no problem with the UDP support of my trojan-go node.
❯ gg -vv curl ip.sb
TRAC[0000] Version: 0.2.3
TRAC[0000] OS/Arch: linux/amd64
TRAC[0000] Using config file: /home/user1/.ggconfig.toml
TRAC[0000] Config:
no_udp=false
test_node_before_use=true
subscription.link=
subscription.select=first
subscription.cache_last_node=true
node=socks5://localhost:7891
cache.subscription.last_node=
INFO[0000] Your proxy server does not support UDP, so we will not redirect UDP traffic.
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 4
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] network: unknown: family: 1, type: 526337
TRAC[0000] new socket (): pid: 9521, fd 3
TRAC[0000] syscall.SYS_CONNECT, syscall.SYS_SENDTO: pid: 9521, fd: 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] network: unknown: family: 1, type: 526337
TRAC[0000] new socket (): pid: 9521, fd 3
TRAC[0000] syscall.SYS_CONNECT, syscall.SYS_SENDTO: pid: 9521, fd: 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] new socket (udp): pid: 9521, fd 3
TRAC[0000] close: pid: 9521, fd 3
TRAC[0000] network: unknown: family: 1, type: 526337
TRAC[0000] new socket (): pid: 9522, fd 7
TRAC[0000] syscall.SYS_CONNECT, syscall.SYS_SENDTO: pid: 9522, fd: 7
TRAC[0000] close: pid: 9522, fd 7
TRAC[0000] network: unknown: family: 1, type: 526337
TRAC[0000] new socket (): pid: 9522, fd 7
TRAC[0000] syscall.SYS_CONNECT, syscall.SYS_SENDTO: pid: 9522, fd: 7
TRAC[0000] close: pid: 9522, fd 7
TRAC[0000] close: pid: 9522, fd 7
TRAC[0000] close: pid: 9522, fd 7
TRAC[0000] close: pid: 9522, fd 7
TRAC[0000] close: pid: 9522, fd 7
TRAC[0000] close: pid: 9522, fd 7
TRAC[0000] close: pid: 9522, fd 7
TRAC[0000] close: pid: 9522, fd 7
TRAC[0000] close: pid: 9522, fd 7
TRAC[0000] close: pid: 9522, fd 7
TRAC[0000] network: unknown: family: 1, type: 526337
TRAC[0000] new socket (): pid: 9522, fd 7
TRAC[0000] syscall.SYS_CONNECT, syscall.SYS_SENDTO: pid: 9522, fd: 7
TRAC[0000] close: pid: 9522, fd 7
TRAC[0000] close: pid: 9522, fd 7
TRAC[0000] close: pid: 9522, fd 7
TRAC[0000] close: pid: 9522, fd 7
TRAC[0000] new socket (udp): pid: 9522, fd 7
TRAC[0000] syscall.SYS_CONNECT, syscall.SYS_SENDTO: pid: 9522, fd: 7
TRAC[0000] syscall.SYS_CONNECT
TRAC[0000] handleINet4 (udp): origin: 1.0.0.1:53, after: 127.0.0.1:22545
TRAC[0000] received udp: 127.0.0.1:40836, tgt: 1.0.0.1:53
TRAC[0000] hijackDNS: lookup: ip.sb. to 198.18.0.1
TRAC[0000] received udp: 127.0.0.1:40836, tgt: 1.0.0.1:53
TRAC[0000] hijackDNS: lookup: ip.sb. to 198.18.0.1
TRAC[0005] syscall.SYS_CONNECT, syscall.SYS_SENDTO: pid: 9522, fd: 7
TRAC[0005] syscall.SYS_SENDTO
TRAC[0005] received udp: 127.0.0.1:40836, tgt: 1.0.0.1:53
TRAC[0005] hijackDNS: lookup: ip.sb. to 198.18.0.1
TRAC[0010] syscall.SYS_CONNECT, syscall.SYS_SENDTO: pid: 9522, fd: 7
TRAC[0010] syscall.SYS_SENDTO
TRAC[0010] received udp: 127.0.0.1:40836, tgt: 1.0.0.1:53
TRAC[0010] hijackDNS: lookup: ip.sb. to 198.18.0.1
TRAC[0015] close: pid: 9522, fd 7
TRAC[0015] syscall.SYS_CONNECT, syscall.SYS_SENDTO: pid: 9522, fd: 6
TRAC[0015] socketInfo of socket cannot found: pid: 9522, fd: 6
TRAC[0015] child 9522 exited
TRAC[0015] close: pid: 9521, fd 6
TRAC[0015] close: pid: 9521, fd 5
curl: (6) Could not resolve host: ip.sb
TRAC[0015] close: pid: 9521, fd 3
TRAC[0015] close: pid: 9521, fd 4
TRAC[0015] child 9521 exited