by Alistair Bayley
There seem to be three separate pieces of software at work (there are probably more, but these are the major players I can identify).
- TortoiseCVS (the view over our code)
- CVS client (in our case CVSNT)
- SSH client (in our case TortoisePlink, but I've used PuTTY's plink.exe below)
Note: as of version 1.6.7, TortoisePlink supports HTTP proxy just like plink. I wrote these instructions when I could only use plink, but I believe everything I've said about plink is true for TortoisePlink.
Firewalls and proxy serversI have to work from behind a firewall. I only have access to the internet (web browsing) via a proxy server. It took a while to figure out how to get SSH working.
The problem: ssh uses port 22. This is typically blocked by firewalls (fair enough). You can tell ssh to use another port with the -P option. SourceForge provides ssh servers on ports 80 and 443 on cvs-ssh.sf.net, specifically for users with these firewall restrictions. Many organisations open these ports for internet access (port 80 is the typical port used for HTTP i.e. standard web browser requests; port 443 is the default port for HTTPS - secure HTTP).
Fine, you say; use port 80. However, I do not have direct access to the internet at all (i.e. to me all ports appear blocked). I must use a proxy server to access the internet, and so I need an SSH client that supports HTTP Proxy tunnelling. Fortunately both PuTTY and TortoisePlink now both do this.
We must create a PuTTY session that uses HTTP proxy, and save it with a name. Plink uses the saved session details to connect to SourceForge via the proxy.
The steps below are summarised as:
- Create PuTTY saved session and activate account
- Create and post SSH keys
- Start and test Pageant
- Test that plink uses Pageant
- Invoke plink from TortoiseCVS
Step 1After getting a sf.net account, you are meant to say:
ssh -l username cvs.sf.netto activate your account (using the same password as with your web-browser). That is, you log in via SSH just once to activate your account. SourceForge allows you to log in, and then spits you out immediately.
You'll need to install PuTTY; I got it from here. I just unzipped and copied the files into the TortoiseCVS folder (because I'm lazy). Puttygen.exe is the only clash/update.
Session: Host name: cvs-ssh.sf.net Port: 80 Saved sessions: cvs-ssh Close window on exit: Never Connection: Auto-login username: <your sf.net username> Connection / Proxy: Proxy type: HTTP Proxy hostname: <proxy address/name> Port: <proxy port>
Click Save (to save the session with name "cvs-ssh"). Test by clicking Open. It should log on to SourceForge (so type your password) and then close immediately.
Step 2Run puttygen.exe and create public and private keys. Save them on a local drive (safer), with a passphrase. Copy the public key to your clipboard, from the field in puttygen labelled "Public key for pasting into OpenSSH authorized keys file:". Don't copy the key from the public key file; it's in the wrong format for SourceForge. Use the Account Maintenance page to post the public key to SourceForge:
Step 3Run Pageant; it doesn't appear to do anything, but a new icon will appear in the system tray (taskbar). Right-click and Add Key (to add the private key you just created); you'll have to enter the passphrase.
Right click on the Pageant icon again and Saved Sessions -> <your session>. It should connect with your SSH key i.e. no password.
Step 4Invoke plink from the NT (*not* Cygwin) command line:
plink.exe -lDue to some obscure bug, plink won't use Pageant keys if invoked from a Cygwin shell.
Step 5Configure Tortoise to use plink.exe. The command line parameters are empty. The CVSROOT will be something like:
Further hints and tips
Module pathWhat module path to specify isn't obvious. Trial and error reveals that the module name is the bit after the project name from:
http://project.cvs.sourceforge.net/viewcvs.py/<project>/<module-name>So this URL:
http://haskell-libs.cvs.sourceforge.net/viewcvs.py/haskell-libs/libs/takusen/would relate to:
CVSROOT=:ext:(Note that there's no leading slash on the module name.) This might seem obvious now but it wasn't at first.