Replace IPSec tunnels by app-level ephemeral TLS sessions.

For some reason giraff doesn't like IPSec.  App-level TLS sessions are
less efficient, but thanks to ansible it still scales well.

7 files changed, 88 insertions, 21 deletions

diff --git a/roles/common/files/etc/postfix/master.cf b/roles/common/files/etc/postfix/master.cf
index e845371..70f7f4e 100644
--- a/roles/common/files/etc/postfix/master.cf
+++ b/roles/common/files/etc/postfix/master.cf
@@ -8,49 +8,44 @@
 # service type  private unpriv  chroot  wakeup  maxproc command + args
 #               (yes)   (yes)   (yes)   (never) (100)
 # ==========================================================================
 smtp      inet  n       -       -       -       -       smtpd
 submission inet n       -       -       -       -       smtpd
 pickup    fifo  n       -       -       60      1       pickup
 cleanup   unix  n       -       -       -       0       cleanup
 qmgr      fifo  n       -       n       300     1       qmgr
 tlsmgr    unix  -       -       -       1000?   1       tlsmgr
 rewrite   unix  -       -       -       -       -       trivial-rewrite
 bounce    unix  -       -       -       -       0       bounce
 defer     unix  -       -       -       -       0       bounce
 trace     unix  -       -       -       -       0       bounce
 verify    unix  -       -       -       -       1       verify
 flush     unix  n       -       -       1000?   0       flush
 proxymap  unix  -       -       n       -       -       proxymap
 proxywrite unix -       -       n       -       1       proxymap
 smtp      unix  -       -       -       -       -       smtp
 smtpl     unix  -       -       -       -       -       smtp
   -o smtp_bind_address=127.0.0.1
-smtps     unix  -       -       -       -       -       smtp
-  -o smtp_bind_address=172.16.0.1
 relay     unix  -       -       -       -       -       smtp
 #       -o smtp_helo_timeout=5 -o smtp_connect_timeout=5
 showq     unix  n       -       -       -       -       showq
 error     unix  -       -       -       -       -       error
 retry     unix  -       -       -       -       -       error
 discard   unix  -       -       -       -       -       discard
 local     unix  -       n       n       -       -       local
 virtual   unix  -       n       n       -       -       virtual
 lmtp      unix  -       -       -       -       -       lmtp
 anvil     unix  -       -       -       -       1       anvil
 scache    unix  -       -       -       -       1       scache
 127.0.0.1:16132 inet n  -       -       -       -       smtpd
 2525      inet  n       -       -       -       -       smtpd
 2526      inet  n       -       -       -       -       smtpd
 2527      inet  n       -       -       -       -       smtpd
-  -o mynetworks=0.0.0.0/0
 127.0.0.1:2580 inet n   -       -       -       -       smtpd
-127.0.0.1:smtp inet n   -       -       -       -       smtpd
-  -o inet_interfaces=127.0.0.1
 reserved-alias unix  -  n       n       -       -       pipe
   flags=Rhu user=nobody argv=/usr/local/sbin/reserved-alias.pl ${sender} ${original_recipient} @fripost.org
 mlmmj     unix  -       n       n       -       -       pipe
   flags=Rhu user=mlmmj argv=/usr/bin/mlmmj-receive -L /var/spool/mlmmj/${domain}/${user}
 amavisfeed unix -       -       n       -       2       lmtp
   -o lmtp_destination_recipient_limit=1000
   -o lmtp_send_xforward_command=yes
   -o lmtp_data_done_timeout=1200s
diff --git a/roles/common/tasks/ipsec.yml b/roles/common/tasks/ipsec.yml
index 51d717f..36807d2 100644
--- a/roles/common/tasks/ipsec.yml
+++ b/roles/common/tasks/ipsec.yml
@@ -1,42 +1,46 @@
 - name: Install strongSwan
   apt: pkg=strongswan-ikev2
 
 - name: Generate a private key and a X.509 certificate for IPSec
   command: genkeypair.sh x509
                          --pubkey=/etc/ipsec.d/certs/{{ inventory_hostname }}.pem
                          --privkey=/etc/ipsec.d/private/{{ inventory_hostname }}.key
                          --dns={{ inventory_hostname }}
                          -t ecdsa -b secp521r1 -h sha512
   register: r1
   changed_when: r1.rc == 0
   failed_when: r1.rc > 1
   notify:
     - Restart IPSec
+  tags:
+    - genkey
 
 - name: Fetch the public part of IPSec's host key
-  sudo: False
   # Ensure we don't fetch private data
+  sudo: False
   fetch: src=/etc/ipsec.d/certs/{{ inventory_hostname }}.pem
          dest=certs/ipsec/
          fail_on_missing=yes
          flat=yes
+  tags:
+    - genkey
 
 # Don't copy our pubkey due to a possible race condition.  Only the
 # remote machine has authority regarding its key.
 - name: Copy IPSec host pubkeys (except ours)
   copy: src=certs/ipsec/{{ item }}.pem
         dest=/etc/ipsec.d/certs/{{ item }}.pem
         owner=root group=root
         mode=0644
   with_items: groups.all | difference([inventory_hostname])
   register: r2
   notify:
     - Restart IPSec
 
 - name: Configure IPSec's secrets
   template: src=etc/ipsec.secrets.j2
             dest=/etc/ipsec.secrets
             owner=root group=root
             mode=0600
   register: r3
   notify:
diff --git a/roles/common/tasks/mail.yml b/roles/common/tasks/mail.yml
index 8572784..74919c8 100644
--- a/roles/common/tasks/mail.yml
+++ b/roles/common/tasks/mail.yml
@@ -27,34 +27,89 @@
   notify:
     - Restart Postfix
 
 - name: Configure Postfix (1)
   copy: src=etc/postfix/master.cf
         dest=/etc/postfix/master.cf
         owner=root group=root
         mode=0644
   notify:
     - Reload Postfix
 
 - name: Configure Postfix (2)
   template: src=etc/postfix/main.cf.j2
             dest=/etc/postfix/main.cf
             owner=root group=root
             mode=0644
   register: r3
   notify:
     - Restart Postfix
 
-- name: Update the static local Postfix database
+- name: Create directory /etc/postfix/ssl
+  file: path=/etc/postfix/ssl
+        state=directory
+        owner=root group=root
+        mode=0755
+  tags:
+    - genkey
+
+- name: Generate a private key and a X.509 certificate for Postfix
+  command: genkeypair.sh x509
+                         --pubkey=/etc/postfix/ssl/{{ ansible_fqdn }}.pem
+                         --privkey=/etc/postfix/ssl/{{ ansible_fqdn }}.key
+                         --dns={{ ansible_fqdn }}
+                         -t ecdsa -b secp384r1 -h sha512
+  register: r4
+  changed_when: r4.rc == 0
+  failed_when: r4.rc > 1
+  tags:
+    - genkey
+
+- name: Fetch Postfix's X.509 certificate
+  # Ensure we don't fetch private data
+  sudo: False
+  fetch: src=/etc/postfix/ssl/{{ ansible_fqdn }}.pem
+         dest=certs/postfix/
+         fail_on_missing=yes
+         flat=yes
+  tags:
+    - genkey
+
+- name: Compile the static local Postfix database
   postmap: cmd=postalias src=/etc/aliases db=cdb
            owner=root group=root
            mode=0644
 
 # We're using CDB
 - name: Delete /etc/aliases.db
   file: path=/etc/aliases.db state=absent
 
+- name: Build the Postfix TLS policy map
+  sudo: False
+  # smtp_tls_fingerprint_digest MUST be sha256!
+  local_action: shell openssl x509 -in certs/postfix/{{ item }}.pem -noout -fingerprint -sha256 | cut -d= -f2
+  with_items: groups.out | sort
+  register: tls_policy
+  changed_when: False
+  when: "'out' not in group_names"
+
+- name: Copy the Postfix TLS policy map
+  template: src=etc/postfix/tls_policy.j2
+            dest=/etc/postfix/tls_policy
+            owner=root group=root
+            mode=0644
+  when: "'out' not in group_names"
+
+- name: Compile the Postfix TLS policy map
+  postmap: cmd=postmap src=/etc/postfix/tls_policy db=cdb
+           owner=root group=root
+           mode=0644
+  when: "'out' not in group_names"
+  register: r5
+  notify:
+    - Restart Postfix
+
 - name: Start Postfix
   service: name=postfix state=started
-  when: not (r1.changed or r2.changed or r3.changed)
+  when: not (r1.changed or r2.changed or r3.changed or r5.changed)
 
 - meta: flush_handlers
diff --git a/roles/common/tasks/main.yml b/roles/common/tasks/main.yml
index 0048443..464abd0 100644
--- a/roles/common/tasks/main.yml
+++ b/roles/common/tasks/main.yml
@@ -1,38 +1,37 @@
 ---
 - include: sysctl.yml   tags=sysctl
 - include: hosts.yml
 - include: apt.yml      tags=apt
 - include: firewall.yml tags=firewall,iptables
 - include: samhain.yml  tags=samhain
 - include: rkhunter.yml tags=rkhunter
 - include: clamav.yml   tags=clamav
 - include: fail2ban.yml tags=fail2ban
 - include: smart.yml    tags=smartmontools,smart
 - include: haveged.yml  tags=haveged,entropy
 - name: Copy genkeypair.sh
   copy: src=usr/local/bin/genkeypair.sh
         dest=/usr/local/bin/genkeypair.sh
         owner=root group=root
         mode=0755
   tags:
-    - genkeypair
-- include: ipsec.yml    tags=strongswan,ipsec
+    - genkey
 - include: logging.yml  tags=logging
 - include: ntp.yml      tags=ntp
 - include: mail.yml     tags=mail,postfix
 
 - name: Install common packages
   apt: pkg={{ item }}
   with_items:
     - ca-certificates
     - daemontools
     - etckeeper
     - ethtool
     - git
     - harden-clients
     - harden-servers
     - htop
     - molly-guard
     - rsync
     - screen
     - telnet-ssl
diff --git a/roles/common/templates/etc/iptables/services.j2 b/roles/common/templates/etc/iptables/services.j2
index 923aa35..3e31f04 100644
--- a/roles/common/templates/etc/iptables/services.j2
+++ b/roles/common/templates/etc/iptables/services.j2
@@ -1,34 +1,39 @@
 # {{ ansible_managed }}
 # Do NOT edit this file directly!
 #
 # direction              protocol     destination port            source port
 # (in|out|inout)[46]?    (tcp|udp|..) (port|port:port|port,port)  (port|port:port|port,port)
 
-inout   udp     500      500                            # ISAKMP
-#inout   udp     4500    4500    # IPSec NAT Traversal
-
 out     tcp     80,443                                  # HTTP/HTTPS
 out     udp     53                                      # DNS
 out     udp     67                                      # DHCP
 
 {% if 'NTP-master' in group_names %}
 out     udp     123      123                            # NTP
 {% endif %}
 
 in      tcp     {{ ansible_ssh_port|default('22') }}    # SSH
 {% if 'MX' in group_names %}
 in      tcp     25                                      # SMTP
 {% endif %}
 {% if 'out' in group_names %}
-#out     tcp     25                                     # SMTP
+in      tcp     {{ postfix_instance.out.port }}
+out     tcp     25                                      # SMTP
+{% else %}
+out     tcp     {{ postfix_instance.out.port }}
 {% endif %}
 {% if 'IMAP' in group_names %}
 in      tcp     993                                     # IMAPS
 in      tcp     4190                                    # ManageSieve
 {% endif %}
+{% if 'MDA' in group_names %}
+in      tcp     {{ postfix_instance.mda.port }}
+{% endif %}
 {% if 'MSA' in group_names %}
 in      tcp     587                                     # SMTP-AUTH
 {% endif %}
 {% if 'webmail' in group_names %}
 in     tcp      80,443                                  # HTTP/HTTPS
+out    tcp      993                                     # IMAP # TODO imapc
+out    tcp      4190
 {% endif %}
diff --git a/roles/common/templates/etc/postfix/main.cf.j2 b/roles/common/templates/etc/postfix/main.cf.j2
index 70d4b98..1abce71 100644
--- a/roles/common/templates/etc/postfix/main.cf.j2
+++ b/roles/common/templates/etc/postfix/main.cf.j2
@@ -1,65 +1,68 @@
 ########################################################################
 # Nullmailer configuration
 #
 # {{ ansible_managed }}
 # Do NOT edit this file directly!
 
 smtpd_banner     = $myhostname ESMTP $mail_name (Debian/GNU)
 biff             = no
 readme_directory = no
 mail_owner       = postfix
 
 myorigin            = /etc/mailname
 myhostname          = {{ ansible_fqdn }}
 mydomain            = {{ ansible_domain }}
 append_dot_mydomain = no
 
 # This server is for internal use only
 mynetworks_style = host
 inet_interfaces  = loopback-only
-inet_protocols   = ipv4
 
 # No local delivery
 mydestination        =
 local_transport      = error:5.1.1 Mailbox unavailable
 alias_maps           =
 local_recipient_maps =
 
 # All aliases are virtual
 default_database_type = cdb
 virtual_alias_maps    = cdb:/etc/aliases
 alias_database        = $virtual_alias_maps
 
-# Forward everything to our internal mailhub
+# Forward everything to our internal outgoing proxy
 {% if 'out' in group_names %}
 relayhost     = [127.0.0.1]:{{ postfix_instance.out.port }}
 {% else %}
 relayhost     = [outgoing.fripost.org]:{{ postfix_instance.out.port }}
 {% endif %}
 relay_domains =
 
-# Tunnel everything through IPSec
-smtp_tls_security_level  = none
 {% if 'out' in group_names %}
-smtp_bind_address        = 127.0.0.1
+smtp_tls_security_level         = none
+smtp_bind_address               = 127.0.0.1
 {% else %}
-smtp_bind_address        = 172.16.0.1
+smtp_tls_security_level         = encrypt
+smtp_tls_cert_file              = $config_directory/ssl/{{ ansible_fqdn }}.pem
+smtp_tls_key_file               = $config_directory/ssl/{{ ansible_fqdn }}.key
+smtp_tls_session_cache_database = btree:$data_directory/smtp_tls_session_cache
+smtp_tls_policy_maps            = cdb:$config_directory/tls_policy
+smtp_tls_fingerprint_digest     = sha256
 {% endif %}
-smtpd_tls_security_level = none
+smtpd_tls_security_level        = none
 
 # Turn off all TCP/IP listener ports except that dedicated to
 # samhain(8), which sadly cannot use pickup through the sendmail binary.
 master_service_disable = !127.0.0.1:16132.inet inet
 
 {% set multi_instance = False %}
 {%- for g in postfix_instance.keys() | sort -%}
   {%- if g in group_names -%}
     {%- if not multi_instance -%}
       {%- set multi_instance = True -%}
 ## Other postfix instances
 multi_instance_wrapper     = $command_directory/postmulti -p --
 multi_instance_enable      = yes
 multi_instance_directories =
     {%- endif %} /etc/postfix-{{ postfix_instance[g].name }}
   {%- endif %}
 {% endfor %}
diff --git a/roles/common/templates/etc/postfix/tls_policy.j2 b/roles/common/templates/etc/postfix/tls_policy.j2
new file mode 100644
index 0000000..b4fc453
--- /dev/null
+++ b/roles/common/templates/etc/postfix/tls_policy.j2
@@ -0,0 +1,6 @@
+# {{ ansible_managed }}
+
+[outgoing.fripost.org]:{{ postfix_instance.out.port }} fingerprint ciphers=high protocols=TLSv1.2
+{% for x in tls_policy.results %}
+   match={{ x.stdout }}
+{% endfor %}