Putty and dynamic port forwarding (SOCKS)

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My setup:

* Development snapshot of putty downloaded today
* A helpful host Out In The World running an sshd on port 443
* An HTTP proxying firewall that only allows HTTP connections out on
port 80, and HTTPS connections out on port 443
* Me, stuck behind said proxy

I've got normal port forwarding working fine for this situation (for
example, I'm forwarding a local port to my POP mail server using this
setup), so I'm aware of how that works.

However, I just noticed today that the latest version of putty has
dynamic port forwarding--i.e. functions as a SOCKS4 proxy, apparently.
Curious to try it out, I added a dynamic port forward to my session
configuration in addition to the local ports I'm already forwarding.
Following the documentation, I added port 1080 as a dynamic port.

However, when I tried to hook up, for example, Yahoo instant messenger
using localhost port 1080 as a SOCKS4 proxy server, the program cannot

Am I doing anything obviously wrong?  I'd like to set this up so that,
for example, I can tell my SOCKS4-proxy-aware mail reading software
(Mozilla) that the mail account is actually NOT located at
localhost:7025 (the static local port I'm currently forwarding), but is
at myhost.com:25, letting the SOCKS4 proxy (Putty, in this case) take
care of the connection details.

Thanks in advance,

Re: Putty and dynamic port forwarding (SOCKS)

Laird Nelson wrote:
Quoted text here. Click to load it

I should mention that I see nothing in the Putty event log to indicate
that Putty has even seen an attempt to connect through it.


Re: Putty and dynamic port forwarding (SOCKS)

Laird Nelson wrote:

Quoted text here. Click to load it

Hmm; it looks like the problem resides with Yahoo messenger: it tries to
validate my IP address, but the validation fails because? presumably?
I'm behind the firewall.  Here's an excerpt from the ypager.log:

   On 10/1 16:16:19| Validate IP fails, localhost

So it looks like Putty is indeed serving as a SOCKS proxy.

Anyone know how to defeat the IP validation failure?


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