Works from LAN, but not from WAN

[o-alquimista]

The client can connect to the server from inside the LAN where the server is, but from outside (WAN) it won't reach client_ready.

• I'm using the -a flag on both sides.
• I've checked that the password is correct on both sides.
• Tried to connect from a broadband from another house (TCP WAN), and from cellular (4G, TCP WAN); the output is the same in both cases.

Server

The server is an OpenWrt router (the default gateway at home) of architecture MIPS "ramips" little-endian. I'm using the precompiled binary from github releases (git version:e5ecd33ec4 build date:Feb 7 2023 08:24:29).

It has a static public ipv4 address, and it is connected to a broadband fiber-optics internet provider via PPPoE. MTU is set to 1492 on the wan interface.

The router is also a Wireguard server, to which I can successfully connect to when I'm away from home.

# udp2raw -s -l 0.0.0.0:40960 -r 127.0.0.1:55820 -k PASSWORD --raw-mode faketcp -a --log-level 5 --fix-gro

Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][INFO]argc=14 udp2raw -s -l 0.0.0.0:40960 -r 127.0.0.1:55820 -k PASSWORD --raw-mode faketcp -a --log-level 5 --fix-gro 
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][INFO]parsing address: 0.0.0.0:40960
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][INFO]its an ipv4 adress
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][INFO]ip_address is {0.0.0.0}, port is {40960}
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][INFO]parsing address: 127.0.0.1:55820
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][INFO]its an ipv4 adress
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][INFO]ip_address is {127.0.0.1}, port is {55820}
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][DEBUG]parsing key option
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][DEBUG]option_index: 6
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][DEBUG]option_index: 2
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][DEBUG]option_index: 37
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][INFO]--fix-gro enabled
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][INFO]important variables: log_level=5:DEBUG raw_mode=faketcp cipher_mode=aes128cbc auth_mode=md5 key=PASSWORD local_addr=0.0.0.0:40960 remote_addr=127.0.0.1:55820 socket_buf_size=1048576 
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][WARN]you can run udp2raw with non-root account for better security. check README.md in repo for more info.
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][INFO]remote_ip=[127.0.0.1], make sure this is a vaild IP address
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][INFO]const_id:3e5ad0fb
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: <30><ce><c1><3c><79><e9><bb><d4><49><5e><b0><2d><d8><50><58><f0>
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: <55><6f><ac><3d><fa><bb><5a><47><60><d7><82><ba><3c><1f><ac><77><33><86><c2><4d><ef><86><d5><ff><aa><6b><8c><fd><1a><72><c7><c7><53><9a><4b><44><95><76><3b><52><61><59><e5><d7><5f><9b><59><94><15><c4><80><40><3a><40><98><05><d9><46><98><d5><7f><a1><52><37>
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: <19><e1><b4><16><d9><ef><d8><e0><fc><90><b7><87><f2><39><11><e3><85><b6><9d><50><ce><85><f0><3c><37><3e><74><f1><0e><ca><44><18><94><b6><02><7d><dc><84><65><26><a7><52><3f><6c><69><07><f2><47><51><0d><20><38><f5><26><b0><61><8a><26><2f><e9><a4><63><2f><04>
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: <65><e5><f6><1b><c0><f6><a0><fc><66><67><36><46><b2><d7><7a><c0><9c><31><ed><3a><f9><e8><9c><4b><4e><ad><dc><38><84><74><68><11><8d><b1><1a><d9><d6><60><6f><ff><ff><13><5e><3d><b0><21><c6><be><8e><fb><cc><87><82><37><96><73><28><f6><46><d2><71><34><64><4e>
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: <64><90><7a><d5><38><5a><90><f8><0e><d7><2d><b2><91><37><d9><81><40><03><fb><37><1b><f1><32><5b><fc><3e><0a><7a><eb><1d><f2><51><db><fc><73><e1><3f><88><aa><65><14><cc><fd><5a><25><ba><2d><52><86><c4><df><81><e1><1b><76><09><72><50><da><19><f0><91><0f><f5>
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][INFO]run_command iptables -N udp2rawDwrW_3e5ad0fb_C0
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][INFO]run_command iptables -F udp2rawDwrW_3e5ad0fb_C0
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][INFO]run_command iptables -I udp2rawDwrW_3e5ad0fb_C0 -j DROP
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][INFO]run_command iptables -I INPUT -p tcp -m tcp --dport 40960 -j udp2rawDwrW_3e5ad0fb_C0
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][WARN]auto added iptables rules
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][DEBUG]error remove fiter
Wed Jun 19 17:48:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:48:09][INFO]now listening at 0.0.0.0:40960
Wed Jun 19 17:51:03 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:03][INFO][CLIENT_IPV4:17529]received syn,sent syn ack back
Wed Jun 19 17:51:04 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:04][INFO][CLIENT_IPV4:17529]received syn,sent syn ack back
Wed Jun 19 17:51:06 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:06][INFO][CLIENT_IPV4:17529]received syn,sent syn ack back
Wed Jun 19 17:51:07 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:07][INFO][CLIENT_IPV4:17529]received syn,sent syn ack back
Wed Jun 19 17:51:08 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:08][INFO][CLIENT_IPV4:17529]received syn,sent syn ack back
Wed Jun 19 17:51:09 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:09][INFO][CLIENT_IPV4:17346]received syn,sent syn ack back
Wed Jun 19 17:51:10 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:10][INFO][CLIENT_IPV4:17346]received syn,sent syn ack back
Wed Jun 19 17:51:11 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:11][INFO][CLIENT_IPV4:17346]received syn,sent syn ack back
Wed Jun 19 17:51:12 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:12][INFO][CLIENT_IPV4:17346]received syn,sent syn ack back
Wed Jun 19 17:51:14 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:14][INFO][CLIENT_IPV4:17346]received syn,sent syn ack back
Wed Jun 19 17:51:14 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:14][INFO][CLIENT_IPV4:17888]received syn,sent syn ack back
Wed Jun 19 17:51:16 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:16][INFO][CLIENT_IPV4:17888]received syn,sent syn ack back
Wed Jun 19 17:51:17 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:17][INFO][CLIENT_IPV4:17888]received syn,sent syn ack back
Wed Jun 19 17:51:18 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:18][INFO][CLIENT_IPV4:17888]received syn,sent syn ack back
Wed Jun 19 17:51:19 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:19][INFO][CLIENT_IPV4:17888]received syn,sent syn ack back
Wed Jun 19 17:51:20 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:20][INFO][CLIENT_IPV4:17205]received syn,sent syn ack back
Wed Jun 19 17:51:21 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:21][INFO][CLIENT_IPV4:17205]received syn,sent syn ack back
Wed Jun 19 17:51:22 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:22][INFO][CLIENT_IPV4:17205]received syn,sent syn ack back
Wed Jun 19 17:51:24 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:24][INFO][CLIENT_IPV4:17205]received syn,sent syn ack back
Wed Jun 19 17:51:25 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:25][INFO][CLIENT_IPV4:17205]received syn,sent syn ack back
Wed Jun 19 17:51:26 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:26][INFO][CLIENT_IPV4:18068]received syn,sent syn ack back
Wed Jun 19 17:51:27 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:27][INFO][CLIENT_IPV4:18068]received syn,sent syn ack back
Wed Jun 19 17:51:28 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:28][INFO][CLIENT_IPV4:18068]received syn,sent syn ack back
Wed Jun 19 17:51:29 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:29][INFO][CLIENT_IPV4:18068]received syn,sent syn ack back
Wed Jun 19 17:51:30 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:30][INFO][CLIENT_IPV4:18068]received syn,sent syn ack back
Wed Jun 19 17:51:31 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:31][INFO][CLIENT_IPV4:17174]received syn,sent syn ack back
Wed Jun 19 17:51:32 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:32][INFO][CLIENT_IPV4:17174]received syn,sent syn ack back
Wed Jun 19 17:51:34 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:34][INFO][CLIENT_IPV4:17174]received syn,sent syn ack back
Wed Jun 19 17:51:35 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:35][INFO][CLIENT_IPV4:17174]received syn,sent syn ack back
Wed Jun 19 17:51:36 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:36][INFO][CLIENT_IPV4:17174]received syn,sent syn ack back
Wed Jun 19 17:51:37 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:37][INFO][CLIENT_IPV4:17430]received syn,sent syn ack back
Wed Jun 19 17:51:38 2024 daemon.info udp2raw[11450]: [2024-06-19 17:51:38][INFO][CLIENT_IPV4:17430]received syn,sent syn ack back

Client

The client is an amd64 laptop running Fedora Workstation 40. It is connected to a different ISP (broadband, fiber-optics too) at a different location.

# udp2raw_amd64 -c -l 0.0.0.0:55820 -r SERVER_IPV4:40960 -k PASSWORD --raw-mode faketcp -a --log-level 5 --fix-gro

[2024-06-19 17:51:03][INFO]argc=14 udp2raw_amd64 -c -l 0.0.0.0:55820 -r SERVER_IPV4:40960 -k PASSWORD --raw-mode faketcp -a --log-level 5 --fix-gro 
[2024-06-19 17:51:03][INFO]parsing address: 0.0.0.0:55820
[2024-06-19 17:51:03][INFO]its an ipv4 adress
[2024-06-19 17:51:03][INFO]ip_address is {0.0.0.0}, port is {55820}
[2024-06-19 17:51:03][INFO]parsing address: SERVER_IPV4:40960
[2024-06-19 17:51:03][INFO]its an ipv4 adress
[2024-06-19 17:51:03][INFO]ip_address is {SERVER_IPV4}, port is {40960}
[2024-06-19 17:51:03][DEBUG]parsing key option
[2024-06-19 17:51:03][DEBUG]option_index: 6
[2024-06-19 17:51:03][DEBUG]option_index: 2
[2024-06-19 17:51:03][DEBUG]option_index: 37
[2024-06-19 17:51:03][INFO]--fix-gro enabled
[2024-06-19 17:51:03][INFO]important variables: log_level=5:DEBUG raw_mode=faketcp cipher_mode=aes128cbc auth_mode=md5 key=PASSWORD local_addr=0.0.0.0:55820 remote_addr=SERVER_IPV4:40960 socket_buf_size=1048576 
[2024-06-19 17:51:03][WARN]you can run udp2raw with non-root account for better security. check README.md in repo for more info.
[2024-06-19 17:51:03][INFO]remote_ip=[SERVER_IPV4], make sure this is a vaild IP address
[2024-06-19 17:51:03][INFO]const_id:fc3e877e
<30><ce><c1><3c><79><e9><bb><d4><49><5e><b0><2d><d8><50><58><f0>
<19><e1><b4><16><d9><ef><d8><e0><fc><90><b7><87><f2><39><11><e3><85><b6><9d><50><ce><85><f0><3c><37><3e><74><f1><0e><ca><44><18><94><b6><02><7d><dc><84><65><26><a7><52><3f><6c><69><07><f2><47><51><0d><20><38><f5><26><b0><61><8a><26><2f><e9><a4><63><2f><04>
<55><6f><ac><3d><fa><bb><5a><47><60><d7><82><ba><3c><1f><ac><77><33><86><c2><4d><ef><86><d5><ff><aa><6b><8c><fd><1a><72><c7><c7><53><9a><4b><44><95><76><3b><52><61><59><e5><d7><5f><9b><59><94><15><c4><80><40><3a><40><98><05><d9><46><98><d5><7f><a1><52><37>
<64><90><7a><d5><38><5a><90><f8><0e><d7><2d><b2><91><37><d9><81><40><03><fb><37><1b><f1><32><5b><fc><3e><0a><7a><eb><1d><f2><51><db><fc><73><e1><3f><88><aa><65><14><cc><fd><5a><25><ba><2d><52><86><c4><df><81><e1><1b><76><09><72><50><da><19><f0><91><0f><f5>
<65><e5><f6><1b><c0><f6><a0><fc><66><67><36><46><b2><d7><7a><c0><9c><31><ed><3a><f9><e8><9c><4b><4e><ad><dc><38><84><74><68><11><8d><b1><1a><d9><d6><60><6f><ff><ff><13><5e><3d><b0><21><c6><be><8e><fb><cc><87><82><37><96><73><28><f6><46><d2><71><34><64><4e>
[2024-06-19 17:51:03][INFO]run_command iptables -N udp2rawDwrW_fc3e877e_C0
[2024-06-19 17:51:03][INFO]run_command iptables -F udp2rawDwrW_fc3e877e_C0
[2024-06-19 17:51:03][INFO]run_command iptables -I udp2rawDwrW_fc3e877e_C0 -j DROP
[2024-06-19 17:51:03][INFO]run_command iptables -I INPUT -s SERVER_IPV4 -p tcp -m tcp --sport 40960 -j udp2rawDwrW_fc3e877e_C0
[2024-06-19 17:51:03][WARN]auto added iptables rules
[2024-06-19 17:51:03][DEBUG]send_raw : from 0.0.0.0 0  to SERVER_IPV4 40960
[2024-06-19 17:51:03][DEBUG]created new udp_fd 9
[2024-06-19 17:51:03][INFO]source_addr is now 192.168.1.7
[2024-06-19 17:51:03][INFO]using port 43709
[2024-06-19 17:51:03][DEBUG]error remove fiter
[2024-06-19 17:51:03][INFO]state changed from client_idle to client_tcp_handshake
[2024-06-19 17:51:03][INFO](re)sent tcp syn
[2024-06-19 17:51:04][INFO](re)sent tcp syn
[2024-06-19 17:51:06][INFO](re)sent tcp syn
[2024-06-19 17:51:07][INFO](re)sent tcp syn
[2024-06-19 17:51:08][INFO](re)sent tcp syn
[2024-06-19 17:51:08][INFO]state back to client_idle from client_tcp_handshake
[2024-06-19 17:51:09][DEBUG]created new udp_fd 10
[2024-06-19 17:51:09][INFO]source_addr is now 192.168.1.7
[2024-06-19 17:51:09][INFO]using port 14806
[2024-06-19 17:51:09][INFO]state changed from client_idle to client_tcp_handshake
[2024-06-19 17:51:09][INFO](re)sent tcp syn
[2024-06-19 17:51:10][INFO](re)sent tcp syn
[2024-06-19 17:51:11][INFO](re)sent tcp syn
[2024-06-19 17:51:12][INFO](re)sent tcp syn
[2024-06-19 17:51:14][INFO](re)sent tcp syn
[2024-06-19 17:51:14][INFO]state back to client_idle from client_tcp_handshake
[2024-06-19 17:51:14][DEBUG]created new udp_fd 10
[2024-06-19 17:51:14][INFO]source_addr is now 192.168.1.7
[2024-06-19 17:51:14][INFO]using port 46288
[2024-06-19 17:51:14][INFO]state changed from client_idle to client_tcp_handshake
[2024-06-19 17:51:14][INFO](re)sent tcp syn
[2024-06-19 17:51:16][INFO](re)sent tcp syn
[2024-06-19 17:51:17][INFO](re)sent tcp syn
[2024-06-19 17:51:18][INFO](re)sent tcp syn
[2024-06-19 17:51:19][INFO](re)sent tcp syn
[2024-06-19 17:51:20][INFO]state back to client_idle from client_tcp_handshake
[2024-06-19 17:51:20][DEBUG]created new udp_fd 10
[2024-06-19 17:51:20][INFO]source_addr is now 192.168.1.7
[2024-06-19 17:51:20][INFO]using port 47535
[2024-06-19 17:51:20][INFO]state changed from client_idle to client_tcp_handshake
[2024-06-19 17:51:20][INFO](re)sent tcp syn
[2024-06-19 17:51:21][INFO](re)sent tcp syn
[2024-06-19 17:51:22][INFO](re)sent tcp syn
[2024-06-19 17:51:24][INFO](re)sent tcp syn
[2024-06-19 17:51:25][INFO](re)sent tcp syn
[2024-06-19 17:51:25][INFO]state back to client_idle from client_tcp_handshake
[2024-06-19 17:51:26][DEBUG]created new udp_fd 10
[2024-06-19 17:51:26][INFO]source_addr is now 192.168.1.7
[2024-06-19 17:51:26][INFO]using port 34288
[2024-06-19 17:51:26][INFO]state changed from client_idle to client_tcp_handshake
[2024-06-19 17:51:26][INFO](re)sent tcp syn
[2024-06-19 17:51:27][INFO](re)sent tcp syn
[2024-06-19 17:51:28][INFO](re)sent tcp syn
[2024-06-19 17:51:29][INFO](re)sent tcp syn
[2024-06-19 17:51:30][INFO](re)sent tcp syn
[2024-06-19 17:51:31][INFO]state back to client_idle from client_tcp_handshake
[2024-06-19 17:51:31][DEBUG]created new udp_fd 10
[2024-06-19 17:51:31][INFO]source_addr is now 192.168.1.7
[2024-06-19 17:51:31][INFO]using port 21084
[2024-06-19 17:51:31][INFO]state changed from client_idle to client_tcp_handshake
[2024-06-19 17:51:31][INFO](re)sent tcp syn
[2024-06-19 17:51:32][INFO](re)sent tcp syn
[2024-06-19 17:51:34][INFO](re)sent tcp syn
[2024-06-19 17:51:35][INFO](re)sent tcp syn
[2024-06-19 17:51:36][INFO](re)sent tcp syn
[2024-06-19 17:51:36][INFO]state back to client_idle from client_tcp_handshake
[2024-06-19 17:51:37][DEBUG]created new udp_fd 10
[2024-06-19 17:51:37][INFO]source_addr is now 192.168.1.7
[2024-06-19 17:51:37][INFO]using port 17330
[2024-06-19 17:51:37][INFO]state changed from client_idle to client_tcp_handshake
[2024-06-19 17:51:37][INFO](re)sent tcp syn
[2024-06-19 17:51:38][INFO](re)sent tcp syn