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On Monday 18 February 2008, Etaoin Shrdlu wrote: |
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> On Monday 18 February 2008, Mick wrote: |
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> > Hi All, |
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> > |
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> > I think that I have confused myself with this. I am behind a |
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> > firewall/http proxy which seems to only allow outbound connections on |
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> > ports 80 & 443 for web browsing. This is not enough for me, as I |
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> > would like to use my mail client to send and receive mail from behind |
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> > the firewall. |
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> > |
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> > I tried connecting to ssh servers which listen on different ports, |
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> > besides tcp/22 and I was not successful. This is probably an |
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> > indication that the internet gateway machine only accepts connections |
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> > for packets that have a destination to ports 80 & 443. |
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> > |
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> > If the above is correct, am I right to assume that to be able to run a |
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> > tunnel through this internet gateway I should run something like: |
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> > |
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> > ssh -L 2222:localhost:443 me@remote_sshd.com |
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> |
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> This command still tries to contact the remote host on port 22, and is |
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> blocked by the firewall. |
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|
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Oops! Yes, the primary ssh connection will take place to port 22 on the |
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server, unless this is specified separately as you show below. |
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> IIUC to exit the local firewall you should have the remote sshd listening |
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> on port 443 or 80. |
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> |
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> ssh -p 443 me@remote_sshd.com |
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> |
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> Of course, the remote /etc/ssh/sshd_config must have "Port 443" (or 80). |
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> If this works and you are able to actually connect to the remote ssh, you |
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> can add local or remote port forwarding to this basic command. |
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> |
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> So, as an example for email, you can do something: |
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> |
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> ssh -p 443 -L 2222:smtpserver:25 me@remote_sshd.com |
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> |
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> and configure your mail client to send to localhost, port 2222. |
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> Another alternative (depending upon how many ports you need to forward) |
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> could be to use SOCKS. |
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With option -D on the server. Hmm, need to explain that the ssh server is NOT |
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the mail server (and last time I looked gmail did not accept ssh connections |
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to their mail servers!), but a router I run at home. The idea is that I will |
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set up corresponding forwarding rules on the router. Is that sound? |
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PS. Unless I missed it Kmail does not have settings for SOCKS. |
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Thank you for your help. :) |
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-- |
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Regards, |
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Mick |
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