ipsec: T1210: T1251: Add more features to remote-access connections

- Adds client/server authentication methods.
- Adds basic verification to remote-access.
- Adds DHCP pool and options to remote-access.
- Cleanup unused PKI files.

5 files changed, 176 insertions, 9 deletions

diff --git a/data/templates/ipsec/charon/dhcp.conf.tmpl b/data/templates/ipsec/charon/dhcp.conf.tmpl
new file mode 100644
index 000000000..2879550a8
--- /dev/null
+++ b/data/templates/ipsec/charon/dhcp.conf.tmpl
@@ -0,0 +1,23 @@
+dhcp {
+    load = yes
+
+{% if options is defined and options.remote_access is defined and options.remote_access.dhcp_pool is defined %}
+{%   if options.remote_access.dhcp_pool.interface is defined %}
+    interface = {{ options.remote_access.dhcp_pool.interface }}
+{%   endif %}
+{%   if options.remote_access.dhcp_pool.server is defined %}
+    server = {{ options.remote_access.dhcp_pool.server }}
+{%   endif %}
+{% endif %}
+
+    # Always use the configured server address.
+    # force_server_address = no
+
+    # Derive user-defined MAC address from hash of IKE identity and send client
+    # identity DHCP option.
+    # identity_lease = no
+
+    # Use the DHCP server port (67) as source port when a unicast server address
+    # is configured.
+    # use_server_port = no
+}
diff --git a/data/templates/ipsec/swanctl.conf.tmpl b/data/templates/ipsec/swanctl.conf.tmpl
index 0eda8479a..00251d44d 100644
--- a/data/templates/ipsec/swanctl.conf.tmpl
+++ b/data/templates/ipsec/swanctl.conf.tmpl
@@ -23,7 +23,7 @@ connections {
 
 pools {
 {%  if remote_access is defined %}
-{%    for ra, ra_conf in remote_access.items() if remote_access is defined %}
+{%    for ra, ra_conf in remote_access.items() if ra_conf.pool.dhcp_enable is not defined %}
     ra-{{ ra }} {
         addrs = {{ ra_conf.pool.prefix }}
         dns = {{ ra_conf.pool.name_server | join(",") }}
@@ -82,7 +82,17 @@ secrets {
 {%  endif %}
 {%  if remote_access is defined %}
 {%    for ra, ra_conf in remote_access.items() if remote_access is defined %}
-{%      if ra_conf.authentication is defined and ra_conf.authentication.local_users is defined and ra_conf.authentication.local_users.username is defined %}
+{%      if ra_conf.authentication.server_mode == 'pre-shared-secret' %}
+    ike_{{ ra }} {
+{%        if ra_conf.authentication.id is defined %}
+        id = "{{ ra_conf.authentication.id }}"
+{%        elif ra_conf.local_address is defined %}
+        id = "{{ ra_conf.local_address }}"
+{%        endif %}
+        secret = "{{ ra_conf.authentication.pre_shared_secret }}"
+    }
+{%      endif %}
+{%      if ra_conf.authentication.client_mode == 'eap-mschapv2' and ra_conf.authentication.local_users is defined and ra_conf.authentication.local_users.username is defined %}
 {%        for user, user_conf in ra_conf.authentication.local_users.username.items() if user_conf.disable is not defined %}
     eap-{{ ra }}-{{ user }} {
         secret = "{{ user_conf.password }}"
diff --git a/data/templates/ipsec/swanctl/remote_access.tmpl b/data/templates/ipsec/swanctl/remote_access.tmpl
index a3a1cf0b2..95f2108fb 100644
--- a/data/templates/ipsec/swanctl/remote_access.tmpl
+++ b/data/templates/ipsec/swanctl/remote_access.tmpl
@@ -10,19 +10,27 @@
         send_certreq = no
         rekey_time = {{ ike.lifetime }}s
         keyingtries = 0
+{%   if rw_conf.pool.dhcp_enable is defined %}
+        pools = dhcp
+{%   else %}
         pools = ra-{{ name }}
+{%   endif %}
         local {
-            auth = pubkey
-{%   if rw_conf.authentication is defined and rw_conf.authentication.id is defined and rw_conf.authentication.use_x509_id is not defined %}
+{%   if rw_conf.authentication.id is defined and rw_conf.authentication.use_x509_id is not defined %}
             id = "{{ rw_conf.authentication.id }}"
 {%   endif %}
-{%   if rw_conf.authentication is defined and rw_conf.authentication.x509 is defined and rw_conf.authentication.x509.certificate is defined %}
+{%   if rw_conf.authentication.server_mode == 'x509' %}
+            auth = pubkey
             certs = {{ rw_conf.authentication.x509.certificate }}.pem
+{%   elif rw_conf.authentication.server_mode == 'pre-shared-secret' %}
+            auth = psk
 {%   endif %}
         }
         remote {
-            auth = eap-mschapv2
+            auth = {{ rw_conf.authentication.client_mode }}
+{%   if rw_conf.authentication.client_mode.startswith("eap") %}
             eap_id = %any
+{%   endif %}
         }
         children {
             ikev2-vpn  {
diff --git a/interface-definitions/vpn_ipsec.xml.in b/interface-definitions/vpn_ipsec.xml.in
index f6b18d1d5..4425ab02a 100644
--- a/interface-definitions/vpn_ipsec.xml.in
+++ b/interface-definitions/vpn_ipsec.xml.in
@@ -648,6 +648,37 @@
                   <valueless/>
                 </properties>
               </leafNode>
+              <node name="remote-access">
+                <properties>
+                  <help>remote-access global options</help>
+                </properties>
+                <children>
+                  <node name="dhcp-pool">
+                    <properties>
+                      <help>DHCP pool options for remote-access</help>
+                    </properties>
+                    <children>
+                      <leafNode name="interface">
+                        <properties>
+                          <help>Interface with DHCP server to use</help>
+                          <completionHelp>
+                            <script>${vyos_completion_dir}/list_interfaces.py</script>
+                          </completionHelp>
+                        </properties>
+                      </leafNode>
+                      <leafNode name="server">
+                        <properties>
+                          <help>DHCP server address</help>
+                          <valueHelp>
+                            <format>ipv4</format>
+                            <description>IPv4 address of the DHCP server</description>
+                          </valueHelp>
+                        </properties>
+                      </leafNode>
+                    </children>
+                  </node>
+                </children>
+              </node>
             </children>
           </node>
           <tagNode name="profile">
@@ -720,6 +751,26 @@
                 <children>
                   #include <include/ipsec/authentication-id.xml.i>
                   #include <include/ipsec/authentication-x509.xml.i>
+                  <leafNode name="client-mode">
+                    <properties>
+                      <help>Client authentication mode</help>
+                      <completionHelp>
+                        <list>eap-tls eap-mschapv2</list>
+                      </completionHelp>
+                      <valueHelp>
+                        <format>eap-tls</format>
+                        <description>EAP-TLS</description>
+                      </valueHelp>
+                      <valueHelp>
+                        <format>eap-mschapv2</format>
+                        <description>EAP-MSCHAPv2</description>
+                      </valueHelp>
+                      <constraint>
+                        <regex>^(eap-tls|eap-mschapv2)$</regex>
+                      </constraint>
+                    </properties>
+                    <defaultValue>eap-mschapv2</defaultValue>
+                  </leafNode>
                   <node name="local-users">
                     <properties>
                       <help>Local user authentication for PPPoE server</help>
@@ -740,6 +791,31 @@
                       </tagNode>
                     </children>
                   </node>
+                  <leafNode name="server-mode">
+                    <properties>
+                      <help>Server authentication mode</help>
+                      <completionHelp>
+                        <list>pre-shared-secret x509</list>
+                      </completionHelp>
+                      <valueHelp>
+                        <format>pre-shared-secret</format>
+                        <description>pre-shared-secret_description</description>
+                      </valueHelp>
+                      <valueHelp>
+                        <format>x509</format>
+                        <description>x509_description</description>
+                      </valueHelp>
+                      <constraint>
+                        <regex>^(pre-shared-secret|x509)$</regex>
+                      </constraint>
+                    </properties>
+                    <defaultValue>x509</defaultValue>
+                  </leafNode>
+                  <leafNode name="pre-shared-secret">
+                    <properties>
+                      <help>Pre-shared-secret used for server authentication</help>
+                    </properties>
+                  </leafNode>
                 </children>
               </node>
               #include <include/generic-description.xml.i>
@@ -753,6 +829,12 @@
                   <help>IP address pool for remote-access users</help>
                 </properties>
                 <children>
+                  <leafNode name="dhcp-enable">
+                    <properties>
+                      <help>Enable DHCP pool for clients on this connection</help>
+                      <valueless/>
+                    </properties>
+                  </leafNode>
                   <leafNode name="exclude">
                     <properties>
                       <help>Local IPv4 or IPv6 pool prefix exclusions</help>
diff --git a/src/conf_mode/vpn_ipsec.py b/src/conf_mode/vpn_ipsec.py
index 76ee64a20..cf23a89c6 100755
--- a/src/conf_mode/vpn_ipsec.py
+++ b/src/conf_mode/vpn_ipsec.py
@@ -46,6 +46,7 @@ dhcp_wait_sleep = 1
 swanctl_dir    = '/etc/swanctl'
 ipsec_conf     = '/etc/ipsec.conf'
 ipsec_secrets  = '/etc/ipsec.secrets'
+charon_dhcp_conf = '/etc/strongswan.d/charon/dhcp.conf'
 interface_conf = '/etc/strongswan.d/interfaces_use.conf'
 swanctl_conf   = f'{swanctl_dir}/swanctl.conf'
 
@@ -150,13 +151,13 @@ def verify_pki(pki, x509_conf):
     ca_cert_name = x509_conf['ca_certificate']
     cert_name = x509_conf['certificate']
 
-    if not dict_search_args(ipsec['pki'], 'ca', ca_cert_name, 'certificate'):
+    if not dict_search_args(pki, 'ca', ca_cert_name, 'certificate'):
         raise ConfigError(f'Missing CA certificate on specified PKI CA certificate "{ca_cert_name}"')
 
-    if not dict_search_args(ipsec['pki'], 'certificate', cert_name, 'certificate'):
+    if not dict_search_args(pki, 'certificate', cert_name, 'certificate'):
         raise ConfigError(f'Missing certificate on specified PKI certificate "{cert_name}"')
 
-    if not dict_search_args(ipsec['pki'], 'certificate', cert_name, 'private', 'key'):
+    if not dict_search_args(pki, 'certificate', cert_name, 'private', 'key'):
         raise ConfigError(f'Missing private key on specified PKI certificate "{cert_name}"')
 
     return True
@@ -190,6 +191,37 @@ def verify(ipsec):
             if 'authentication' not in profile_conf:
                 raise ConfigError(f"Missing authentication on {profile} profile")
 
+    if 'remote_access' in ipsec:
+        for name, ra_conf in ipsec['remote_access'].items():
+            if 'esp_group' in ra_conf:
+                if 'esp_group' not in ipsec or ra_conf['esp_group'] not in ipsec['esp_group']:
+                    raise ConfigError(f"Invalid esp-group on {name} remote-access config")
+            else:
+                raise ConfigError(f"Missing esp-group on {name} remote-access config")
+
+            if 'ike_group' in ra_conf:
+                if 'ike_group' not in ipsec or ra_conf['ike_group'] not in ipsec['ike_group']:
+                    raise ConfigError(f"Invalid ike-group on {name} remote-access config")
+            else:
+                raise ConfigError(f"Missing ike-group on {name} remote-access config")
+
+            if 'authentication' not in ra_conf:
+                raise ConfigError(f"Missing authentication on {name} remote-access config")
+
+            if ra_conf['authentication']['server_mode'] == 'x509':
+                if 'x509' not in ra_conf['authentication']:
+                    raise ConfigError(f"Missing x509 settings on {name} remote-access config")
+
+                x509 = ra_conf['authentication']['x509']
+
+                if 'ca_certificate' not in x509 or 'certificate' not in x509:
+                    raise ConfigError(f"Missing x509 certificates on {name} remote-access config")
+
+                verify_pki(ipsec['pki'], x509)
+            elif ra_conf['authentication']['server_mode'] == 'pre-shared-secret':
+                if 'pre_shared_secret' not in ra_conf['authentication']:
+                    raise ConfigError(f"Missing pre-shared-key on {name} remote-access config")
+
     if 'site_to_site' in ipsec and 'peer' in ipsec['site_to_site']:
         for peer, peer_conf in ipsec['site_to_site']['peer'].items():
             has_default_esp = False
@@ -282,6 +314,15 @@ def verify(ipsec):
                         if ('local' in tunnel_conf and 'prefix' in tunnel_conf['local']) or ('remote' in tunnel_conf and 'prefix' in tunnel_conf['remote']):
                             raise ConfigError(f"Local/remote prefix cannot be used with ESP transport mode on tunnel {tunnel} for site-to-site peer {peer}")
 
+def cleanup_pki_files():
+    for path in [CERT_PATH, CA_PATH, CRL_PATH, KEY_PATH]:
+        if not os.path.exists(path):
+            continue
+        for file in os.listdir(path):
+            file_path = os.path.join(path, file)
+            if os.path.isfile(file_path):
+                os.unlink(file_path)
+
 def generate_pki_files(pki, x509_conf):
     ca_cert_name = x509_conf['ca_certificate']
     ca_cert_data = dict_search_args(pki, 'ca', ca_cert_name, 'certificate')
@@ -308,6 +349,8 @@ def generate_pki_files(pki, x509_conf):
         f.write(wrap_private_key(key_data, protected))
 
 def generate(ipsec):
+    cleanup_pki_files()
+
     if not ipsec:
         for config_file in [ipsec_conf, ipsec_secrets, interface_conf, swanctl_conf]:
             if os.path.isfile(config_file):
@@ -371,6 +414,7 @@ def generate(ipsec):
 
     render(ipsec_conf, 'ipsec/ipsec.conf.tmpl', data)
     render(ipsec_secrets, 'ipsec/ipsec.secrets.tmpl', data)
+    render(charon_dhcp_conf, 'ipsec/charon/dhcp.conf.tmpl', data)
     render(interface_conf, 'ipsec/interfaces_use.conf.tmpl', data)
     render(swanctl_conf, 'ipsec/swanctl.conf.tmpl', data)