pufferffish
Garbage data when using SOCKS 5 proxy to IPv6
While I'm not 100% sure the issue comes from wireproxy, it is to be noted that with another SOCKS 5 proxy (ssh -D) I'm not observing this issue.
When connecting to an IPv6 TCP target via the SOCKS 5 proxy of wireproxy, some garbage data are inserted at the beggining of the connection, breaking the application protocol. See the following example with SSH
Environment
Client: SSH over WireProxy 1.0.9 over macOS 14.4.1 Wireguard endpoint: mikrotik router (RouterOS 7.14.3) Server: SSH (OpenSSH_9.2, OpenSSL 3.0.11 19 Sep 2023) on Debian 12
It is to be noted I do not have any issue with "official" wireguard clients (either on iOS or macOS)
Direct connection from a client on the same LAN than the server
- IPv4
$ nc 172.29.47.10 22
SSH-2.0-OpenSSH_9.2p1 Debian-2
- IPv6
$ nc fd00:172:29:47::10 22
SSH-2.0-OpenSSH_9.2p1 Debian-2
Using WireProxy with TCPClientTunnel
- IPv4
# WireProxy Configuration file
WGConfig = /path/to/wireguard.conf
[TCPClientTunnel]
BindAddress = 127.0.0.1:25345
Target = 172.29.47.10:22
$ nc 127.0.0.1 25345
SSH-2.0-OpenSSH_9.2p1 Debian-2
- IPv6
# WireProxy Configuration file
WGConfig = /path/to/wireguard.conf
[TCPClientTunnel]
BindAddress = 127.0.0.1:25345
Target = [fd00:172:29:47::10]:22
$ nc 127.0.0.1 25345
SSH-2.0-OpenSSH_9.2p1 Debian-2
Using WireProxy with Socks5
# WireProxy Configuration file
WGConfig = /path/to/wireguard.conf
[Socks5]
BindAddress = 127.0.0.1:25345
- IPv4
nc -X 5 -x 127.0.0.1:25345 172.29.47.10 22
SSH-2.0-OpenSSH_9.2p1 Debian-2
- IPv6
nc -X 5 -x 127.0.0.1:25345 fd00:172:29:47::10 22
I�SSH-2.0-OpenSSH_9.2p1 Debian-2
Note the garbage data before the SSH banner
The same can be observed with an HTTP server
- IPv4 (it waits for me to enter a request)
$ nc -X 5 -x 127.0.0.1:25344 172.29.47.26 80
GET /
HTTP/1.1 400 Bad Request
Content-Type: text/plain; charset=utf-8
Connection: close
400 Bad Request
- IPv6 (it immediately prints some garbage)
$ nc -X 5 -x 127.0.0.1:25344 fd00:172:29:47::26 80
I��
I notice this too.. IPv6 fails:
$ curl -v -x socks5://user:pass@[::1]:1234 https://ipv6.jamieweb.net/
curl: (97) Can't complete SOCKS5 connection to ipv6.jamieweb.net. (4)
IPv4 works fine
$ curl -x socks5://user:pass@[::1]:8922 https://ipv4.jamieweb.net/
<html>
<head><title>IPv4 Test Page</title></head>
[..]
</html>
Edit: Nvm, probably my problem is caused by the VPN Provider (Proton VPN) not supporting IPV6 by default. It also happens when using wireproxy as HTTP Proxy.
