1. File Transfer and Use of Clear Text Passwords Update NERSC Users Group Meeting Stephen Lau NERSC June 21, 2015

2. NUG Meeting June 21, 2015 Clear Text Passwords Clear Text Passwords pose significant security risk –Major source of security compromises NERSC policy to eliminate clear text passwords NERSC does not allow clear text shell sessions –Current primary exposure for NERSC is in file transfer

3. NUG Meeting June 21, 2015 Clear Text Password Goals and Challenges Goals –Eliminate all clear text password access to NERSC –Continue to allow outbound ftp to non-NERSC sites Challenges –Unlike telnet/ssh, no universal cross-platform solution –Many solutions still in development phase

4. NUG Meeting June 21, 2015 File Transfer Options Use scp or sftp http://hpcf.nersc.gov/help/access/ssh.html scp –Works with SSHv1 and SSHv2 –Data stream encrypted (performance hit) sftp –Works with SSHv2 –Data stream encrypted (performance hit) –Similar interface to ftp

5. NUG Meeting June 21, 2015 File Transfer Options If performance becomes an issue try ftp with ssh tunneling http://hpcf.nersc.gov/help/access/ssh.html ftp with ssh tunneling –Works with SSHv1 and SSHv2 –Data stream unencrypted (no performance hit) –Caveats Requires set up Potential port collision failures

6. NUG Meeting June 21, 2015 Availability sftp, ssh, scp available on: –Seaborg –Crays –Newton - Symbolic Mathematics and Statistics Server –Escher – Visualization Server –PDSF

7. NUG Meeting June 21, 2015 File Transfer to HPSS sftp, ssh, scp not available to HPSS Possible future solution of gsi_ftp –Not production ready Allow use of current clients without transmitting easily sniffed passwords –http://hpcf.nersc.gov/storage/hpss/ftp_nopass.htmlhttp://hpcf.nersc.gov/storage/hpss/ftp_nopass.html

8. NUG Meeting June 21, 2015 Key Points to Remember Protect your private keys –Don’t put them on publicly accessible systems Put a passphrase on your keys –Ssh-keygen allows you to generate a key with no passphrase –DO NOT do this Don’t telnet from home to work and then SSH into NERSC –Defeats the use of SSH

9. NUG Meeting June 21, 2015 NERSC PKI Infrastructure DOE Science Grid Certificate Authority –ESNet –Establishes identity Site Registration Authorities / Managers –Site authorization Current state –ESnet has working CA –NERSC has a prototype RA

10. NUG Meeting June 21, 2015 NERSC PKI Infrastructure Key points –ESNet verifies certificates –NERSC provides authorization Still need to go through NERSC authorization process Certificate interoperability with NIM Even if certificate issued by another organization