Re: two questions about ssh tunneling

[Tyler MacDonald <tyler@macdonald.name>]

Tudod Ki <tudodki88@yahoo.com> wrote:
> if I:
> 
> ssh -fND localhost:6000 somebody@192.168.56.5 -p PORTNUMBER
> 
> from computer "A" to computer "B" [B = 192.168.56.5] then I can set the SOCKS proxy for e.g.: Firefox to use "localhost:6000" on computer "A". Ok. I can surf the web through "B".
> 
> But:

> - Can anyone sniff the traffic of "A"? [e.g.: computers on same subnet as
> - "A"] Like DNS requests?  - I think no, but I'm not sure :O

  I believe when you use SOCKS, your browser stops doing DNS resolution and
just hands the hostnames directly to the SOCKS server. So all they would be
able to sniff is your encrypted SSH session, which they (hopefully) can't
decrypt.

> - Can anyone sniff the traffic of computer "B"? e.g.: B computer is at a
> - server farm [others in the farm can see the traffic?] - I think yes, but
> - I'm not sure :O

  Yes, that's possible. However, in most colocated environments, you are on
a switch, not a hub -- so in that case, the attacker would have to be
sniffing directly from a router to see your traffic. If you want to know for
sure, ask your ISP.

	- Tyler