SSH Hardening, gnah.

common.yml

@@ -63,6 +63,27 @@
                 }
             }
 
+    # From https://infosec.mozilla.org/guidelines/openssh
+    - name: SSHd hardening
+      blockinfile:
+        marker: "# {mark} ANSIBLE MANAGED BLOCK (KexAlgorithms, Ciphers, MACs)"
+        path: /etc/ssh/sshd_config
+        state: present
+        create: true
+        block: |
+          KexAlgorithms curve25519-sha256@libssh.org,ecdh-sha2-nistp521,ecdh-sha2-nistp384,ecdh-sha2-nistp256,diffie-hellman-group-exchange-sha256
+          Ciphers chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com,aes256-ctr,aes192-ctr,aes128-ctr
+          MACs hmac-sha2-512-etm@openssh.com,hmac-sha2-256-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-512,hmac-sha2-256,umac-128@openssh.com
+
+          HostKey /etc/ssh/ssh_host_ed25519_key
+          HostKey /etc/ssh/ssh_host_rsa_key
+          HostKey /etc/ssh/ssh_host_ecdsa_key
+
+          AuthenticationMethods publickey
+          LogLevel VERBOSE
+      notify: restart sshd
+      tags: ssh
+
     - name: Setup letsencrypt
       include_role: name=julienpalard.nginx_letsencrypt
       tags: always
@@ -77,3 +98,6 @@
   handlers:
     - name: reload fail2ban
       service: name=fail2ban state=reloaded
+
+    - name: reload sshd
+      service: name=sshd state=restarted