Various SSH configuration improvements

modules/ssh/templates/sshd_config.erb

 # Package generated configuration file
 # See the sshd_config(5) manpage for details
 
 # What ports, IPs and protocols we listen for
 Port 22
 # Use these options to restrict which interfaces/protocols sshd will bind to
 #ListenAddress ::
 #ListenAddress 0.0.0.0
 Protocol 2
 # HostKeys for protocol version 2
 HostKey /etc/ssh/ssh_host_rsa_key
 HostKey /etc/ssh/ssh_host_dsa_key
 HostKey /etc/ssh/ssh_host_ecdsa_key
 #Privilege Separation is turned on for security
 UsePrivilegeSeparation yes
 
 # Lifetime and size of ephemeral version 1 server key
 KeyRegenerationInterval 3600
 ServerKeyBits 768
 
 # Logging
 SyslogFacility AUTH
 LogLevel INFO
 
 # Authentication:
 LoginGraceTime 120
-PermitRootLogin yes
+PermitRootLogin no
 StrictModes yes
 
 RSAAuthentication yes
 PubkeyAuthentication yes
 #AuthorizedKeysFile     %h/.ssh/authorized_keys
 
 # Don't read the user's ~/.rhosts and ~/.shosts files
 IgnoreRhosts yes
 # For this to work you will also need host keys in /etc/ssh_known_hosts
 RhostsRSAAuthentication no
 # similar for protocol version 2
 HostbasedAuthentication no
 # Uncomment if you don't trust ~/.ssh/known_hosts for RhostsRSAAuthentication
 #IgnoreUserKnownHosts yes
 
 # To enable empty passwords, change to yes (NOT RECOMMENDED)
 PermitEmptyPasswords no
 
 # Change to yes to enable challenge-response passwords (beware issues with
 # some PAM modules and threads)
 ChallengeResponseAuthentication no
 
 # Change to no to disable tunnelled clear text passwords
-#PasswordAuthentication yes
+PasswordAuthentication no
 
 # Kerberos options
 #KerberosAuthentication no
 #KerberosGetAFSToken no
 #KerberosOrLocalPasswd yes
 #KerberosTicketCleanup yes
 
 # GSSAPI options
 #GSSAPIAuthentication no
 #GSSAPICleanupCredentials yes
 
-X11Forwarding yes
+AllowAgentForwarding no
+AllowTcpForwarding no
+X11Forwarding no
 X11DisplayOffset 10
 PrintMotd no
 PrintLastLog yes
 TCPKeepAlive yes
+PermitUserEnvironment yes
 #UseLogin no
 
 #MaxStartups 10:30:60
 #Banner /etc/issue.net
 
 # Allow client to pass locale environment variables
 AcceptEnv LANG LC_*
 
 Subsystem sftp /usr/lib/openssh/sftp-server
 
 # Set this to 'yes' to enable PAM authentication, account processing,
 # and session processing. If this is enabled, PAM authentication will
 # be allowed through the ChallengeResponseAuthentication and
 # PasswordAuthentication.  Depending on your PAM configuration,
 # PAM authentication via ChallengeResponseAuthentication may bypass
 # the setting of "PermitRootLogin without-password".
 # If you just want the PAM account and session checks to run without
 # PAM authentication, then enable this but set PasswordAuthentication
 # and ChallengeResponseAuthentication to 'no'.
 UsePAM yes
 
 <%= custom_configuration %>