How to make Tun2socks work on Debian?

[Tutez64]

Hello, I'm having trouble getting Tun2socks to work on my fresh Debian 11.3 VM.

Here is my original ip route

I started by trying this:

ip tuntap add mode tun dev tun0
ip addr add 198.18.0.1/15 dev tun0
ip link set dev tun0 up

ip route del default
ip route add default via 198.18.0.1 dev tun0 metric 1
ip route add default via 10.0.2.2 dev enp0s3 metric 10

tun2socks -device tun0 -proxy socks5://host:port -interface enp0s3

and then Tun2socks seemed to work but I wasn't able to access websites, Firefox was loading for a long time and then giving me an error:



I can ping websites.

I tried adding this:

iptables -t nat -A PREROUTING -p udp --dport 53 -j DNAT --to 8.8.8.8:53;
iptables -t nat -A POSTROUTING -p udp -d 8.8.8.8 --dport 53 -o eth3 -j MASQUERADE;
sysctl net.ipv4.conf.all.rp_filter=0
sysctl net.ipv4.conf.enp0s3.rp_filter=0

but I saw no change

Then I rebooted and tried this:

ip tuntap add mode tun dev tun0
ip addr add 198.18.0.1/15 dev tun0
ip link set dev tun0 up
 
ip route replace default dev tun0
 
tun2socks -device tun0 -proxy socks5://host:port -interface enp0s3

Other than that the result is the same, I can ping websites and Firefox give the same error.

I tried adding this again:

iptables -t nat -A PREROUTING -p udp --dport 53 -j DNAT --to 8.8.8.8:53;
iptables -t nat -A POSTROUTING -p udp -d 8.8.8.8 --dport 53 -o eth3 -j MASQUERADE;
sysctl net.ipv4.conf.all.rp_filter=0
sysctl net.ipv4.conf.enp0s3.rp_filter=0

but I saw no change again

I tried others things like changing my DNS and changing things here and there but none of them worked.

I'm not good at networking so I don't know what am I wrong, I've been trying to find a working proxifier for months (tried Redsocks, Redsocks 2, Tsocks, Proxychains and probably other I forgot) but I either can't make them to work or my IP leaks. Your program seems to be the best option since other are old and often not maintened since years, but I just can't find how to make it works.

[xjasonlyu]

Hi, your first trying seems good to me.

Can you put your route table here after running those commands?

ip tuntap add mode tun dev tun0
ip addr add 198.18.0.1/15 dev tun0
ip link set dev tun0 up

ip route del default
ip route add default via 198.18.0.1 dev tun0 metric 1
ip route add default via 10.0.2.2 dev enp0s3 metric 10

tun2socks -device tun0 -proxy socks5://host:port -interface enp0s3

it’s weird it shows no route error.

[Tutez64]

Oops sorry I put the wrong image, I corrected the message, check again.

[xjasonlyu]

Normally, iptables is not needed in this case. Your route table seems fine to me and the log confirms that.

In my opinion, it might be a DNS issue which caused by your socks5 server behind the VM NAT.

Some socks5 server implementation doesn't work properly in those NAT-involved case (for UDP).

Would you mind telling me what the socks5 server you are using?

[Tutez64]

I'm using this provider: (edited), I can ask them for info if needed.