How To Get Set Up To Use CVS (To Check-Out And Check-In) From A Windows Platform

Setting up CVS to work on a Windows platform and to use SSH is not straightforward.  For this reason, we present a complete guide here.  Major sections are separated by horizontal lines.

Why SSH And SCP (Secure Protocols) Are Required For Accessing SourceForge

SourceForge has a page explaining this, which is very informative.  This page is recommended reading.  (If this page ever disappears, here is a .PDF snapshot of this page as of 06/2001.)

Warning:  There Are Different Distributions And Implementations Of SSH And SCP

There are several distributions of SSH and SCP clients.  They are not all compatible with CVS.  We do not know the reasons for this, but please be aware of this.  We do not understand the interface between CVS and SSH (i.e. how CVS uses SSH), or why individual distributions do or do not work.

Here are the distributions that we are aware of:

• SSH Secure Shell For Windows:  The company SSH makes a product called SSH Secure Shell For Windows.  Very generously, it is encouraged that you purchase the product, but for individual use for non-profit purposes, it can be downloaded for free (without technical support).  This product also includes a secure file transfer client, with a good graphical interface including the ability to cut and paste entire directories from Windows Explorer.  This product is full-featured and works wonderfully for transferring files to and from SourceForge (especially for uploading web pages).  Unfortunately, we have not found a way to use it with CVS.
• Putty:  Putty is a  free distribution of SSH and SCP.  Putty is very helpful for interactive use, but we have not found a way for it to be used with CVS.
• An Unknown Free Distribution:  The best distribution we've found is described at A Quick And Dirty Guide To Using SSH And CVS With SourceForge In A Win32 Environment (.PDF backup as of 06/01).  This distribution is found here.  There are two drawbacks found to this distribution:
  • It can't change AUTOEXEC.BAT on Windows NT and Windows 2000.  This means that the file must be changed manually or one must setup environment variables a different way.
  • The ssh-keygen program with this distribution does not work.  One might want to use ssh-keygen to generate a public/private keypair so that one can use CVS without needing to enter a password--this is described here (.PDF backup as of 06/01).

We discuss how to work around these limitations in a little bit more detail elsewhere in this document.

Obtaining And Setting Up The Recommended Distributions Of SSH And CVS For Use With SourceForge

This section describes the steps to set up SSH and CVS on a Windows platform for use with SourceForge.  We do not claim that this is the only way to do this.  We use only the command-line interface (products like WinCVS are not discussed).  Also, because hard drives are so large now, most users can place all CVS'd materials on their C: drive.  For this reason, only the C: drive is discussed.

• These instructions come primarily from A Quick And Dirty Guide To Using SSH And CVS With SourceForge In A Win32 Environment (.PDF backup as of 06/01).  This is recommended reading to start with.
• Obtain the command line version of CVS for Windows.  This can be obtained at the official CVS site (and you are searching for the command-line client for Windows).  If this site is down or you are not sure what to get or you want to be sure you are using what we are using, the .ZIP file is mirrored here.  (We use CVS 1.11, which seems to work perfectly.)
• Unzip the file and place CVS.EXE in the right place for your system.  This would generally be the place where other command-line utilities from Microsoft are stored (PING.EXE, TELNET.EXE, XCOPY.EXE, etc.).  A good strategy is to search for these common command-line utilities and put CVS.EXE in the same place.  On a Windows 2000 machine, the correct directory is:

C:\WINNT\SYSTEM32

but on other versions of Windows this directory containing common command-line utilities might be a different one.

• Obtain the recommended distribution of SSH here.  If this site is down, here is a mirror of the distribution.  Because of the potential difficulties in NT systems (the AUTOEXEC.BAT file can't be changed), it isn't recommended that you do the installation.  Instead, unzip the distribution, then unzip the .ZIP file contained in it, then copy the following files to the same directory that was identified as the right place for CVS.EXE, above:
  • SSH.EXE
  • SCP.EXE
  • SSH-KEYGEN.EXE
  • GMP.DLL
  • ZLIB.DLL
• Create a home directory for yourself:

mkdir c:\home

• Create an etc directory for yourself.

mkdir c:\etc

• In your \home directory, create a batch file which sets up environment variables for using SSH and CVS.  A good name for this batch file might be ENVSET.BAT or CVSSET.BAT.  This file might also be placed in the same directory as CVS.EXE.  We will assume (for this example), that this batch file is named ENVSET.BAT and resides in c:\home.  The batch file should look like this:

set CVSROOT=:ext:username@cvs.projectname.sourceforge.net:/cvsroot/projectname

set USERNAME=username

set HOMEDRIVE=c:

set HOME=\home 

set HOMEPATH=\home

set CVS_RSH=ssh

where username and projectname should be substituted as described above.

• Open a DOS shell.  Run the batch file which was created above.  Note that this batch file must be run after a DOS shell is opened but before SSH or CVS are used (i.e. every time you prepare to use CVS from a DOS box).  Another alternative is to place the same commands as are in this batch file in AUTOEXEC.BAT.  Leave this DOS box open.
• Open a connection to the Internet.  For example, log on to AOL or dial up some other way.
• Test your ssh connection to SourceForge.  To do this, in the DOS type:

ssh -l username projectname.sourceforge.net

where username is your SourceForge login ID and projectname is the name assigned to your project.  At this point you should be prompted for your password (the same password you use to log into SourceForge).  After you enter your password, you should then receive the traditional Linux login messages and prompt.  If you cannot log in, it is pointless to try to use CVS because that cannot work either.  This test must pass.  You must be able to login using this method before you can go further in these instructions.

If you were able to log in, use CTRL-D to logout, but leave the DOS box open.

• At this point in the instructions you will be able to use CVS successfully.  In the DOS box, change directories as appropriate and issue standard CVS commands.  You will be prompted for a password.  Remember that each time you open a DOS box you must use ENVSET.BAT to set the environment variables or CVS will not work.
• At this point in the instructions, CVS is functional.  The remaining instructions are to eliminate the burden of password entry.  Strictly speaking, this is not necessary, but it is a great convenience.
• Create an SSH keypair.  Unfortunately, the ssh-keygen program above does not seem to work correctly for Windows (can anybody get it to work?).  The best alternative is to log in to the SourceForge servers using SSH.EXE as described in the test above, then run ssh-keygen there.  When you do this, the public and private keys (identity.pub and identity) will then be placed in the .ssh folder of your home directory.  When you generate the keypair, choose no passphrase (just hit the RETURN key at any prompt for a passphrase or password).  (You do not want to generate a passphrase because this would need to be entered each time you use CVS, which is surely not what you desire.)
• Copy the two files identity and identity.pub from ~/.ssh on the SourceForge server to \home\.ssh on your Windows machine.  This was done using the SSH Secure Shell For Windows secure file transfer program.  We have not attempted doing this without using file transfer software, and are not sure how to do it, since the identity file is binary.  (We welcome suggestions here.)
• Delete the file identity from the SourceForge server.  One does not want the private key hanging around.  However, the public key identity.pub should stay there.
• Find the Account Preferences for your user ID in the set of SourceForge web pages, find the SSH/CVS keys near the bottom of the page, and paste the contents of identity.pub into the space in the web page.
• Within 24 hours, CVS should stop nagging you for passwords when you use it. 

This site is maintained by Dave Ashley (dtashley@aol.com).