Secure Shell and FIPS-140

Oracle Solaris provides a FIPS-140 option for the server side and the client side. FIPS mode, where Secure Shell uses the FIPS-140 mode of OpenSSL, is not the default. You can invoke FIPS mode on the command line, as in ssh -o "UseFIPS140 yes" remote-host. As an alternative, you can set a keyword in the configuration files.

Briefly, the implementation consists of the following:

• The following FIPS-approved ciphers are available on the server and client side: aes128-cbc, aes192-cbc, and aes256-cbc.

  3des-cbc is available by default on the client side, but it is not in the server side cipher list because of potential security risks.

• The following FIPS-approved Message Authentication Codes (MAC) are available:

  • hmac-sha1, hmac-sha1-96

  • hmac-sha2-256, hmac-sha2-256-96

  • hmac-sha2-512, hmac-sha2-512-96

• Four server-client configurations are supported:

  • No FIPS mode on either client or server side

  • FIPS mode on both the client and server side

  • FIPS mode on the server side, but no FIPS on client side

  • No FIPS mode on the server side, but FIPS mode on the client side

• The ssh-keygen command has an option to generate the user's private key in the PKCS #8 format that Secure Shell clients in FIPS mode require. For more information, see the ssh-keygen(1) man page.

For more information about FIPS operations in Secure Shell, see the sshd(1M), sshd_config(4), ssh(1), and ssh_config(4) man pages.

When you use a Sun Crypto Accelerator 6000 card for Secure Shell operations, Secure Shell runs with FIPS-140 support at Level 3. Level 3 hardware is certified to resist physical tampering, use identity-based authentication, and isolate the interfaces that handle critical security parameters from the hardware's other interfaces.