Merge pull request #3204 from vyos/mergify/bp/sagitta/pr-2965

T5872: ipsec remote access VPN: support dhcp-interface. (backport #2965)

2 files changed, 64 insertions, 62 deletions

diff --git a/src/conf_mode/vpn_ipsec.py b/src/conf_mode/vpn_ipsec.py
index 46f041cce..0c2f232df 100755
--- a/src/conf_mode/vpn_ipsec.py
+++ b/src/conf_mode/vpn_ipsec.py
@@ -72,7 +72,7 @@ KEY_PATH    = f'{swanctl_dir}/private/'
 CA_PATH     = f'{swanctl_dir}/x509ca/'
 CRL_PATH    = f'{swanctl_dir}/x509crl/'
 
-DHCP_HOOK_IFLIST = '/tmp/ipsec_dhcp_waiting'
+DHCP_HOOK_IFLIST = '/tmp/ipsec_dhcp_interfaces'
 
 def get_config(config=None):
     if config:
@@ -91,6 +91,7 @@ def get_config(config=None):
                                  with_recursive_defaults=True,
                                  with_pki=True)
 
+    ipsec['dhcp_interfaces'] = set()
     ipsec['dhcp_no_address'] = {}
     ipsec['install_routes'] = 'no' if conf.exists(base + ["options", "disable-route-autoinstall"]) else default_install_routes
     ipsec['interface_change'] = leaf_node_changed(conf, base + ['interface'])
@@ -226,6 +227,32 @@ def verify(ipsec):
     if 'remote_access' in ipsec:
         if 'connection' in ipsec['remote_access']:
             for name, ra_conf in ipsec['remote_access']['connection'].items():
+                if 'local_address' not in ra_conf and 'dhcp_interface' not in ra_conf:
+                    raise ConfigError(f"Missing local-address or dhcp-interface on remote-access connection {name}")
+
+                if 'dhcp_interface' in ra_conf:
+                    dhcp_interface = ra_conf['dhcp_interface']
+
+                    verify_interface_exists(dhcp_interface)
+                    dhcp_base = directories['isc_dhclient_dir']
+
+                    if not os.path.exists(f'{dhcp_base}/dhclient_{dhcp_interface}.conf'):
+                        raise ConfigError(f"Invalid dhcp-interface on remote-access connection {name}")
+
+                    ipsec['dhcp_interfaces'].add(dhcp_interface)
+
+                    address = get_dhcp_address(dhcp_interface)
+                    count = 0
+                    while not address and count < dhcp_wait_attempts:
+                        address = get_dhcp_address(dhcp_interface)
+                        count += 1
+                        sleep(dhcp_wait_sleep)
+
+                    if not address:
+                        ipsec['dhcp_no_address'][f'ra_{name}'] = dhcp_interface
+                        print(f"Failed to get address from dhcp-interface on remote-access connection {name} -- skipped")
+                        continue
+
                 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")
@@ -383,6 +410,8 @@ def verify(ipsec):
                 if not os.path.exists(f'{dhcp_base}/dhclient_{dhcp_interface}.conf'):
                     raise ConfigError(f"Invalid dhcp-interface on site-to-site peer {peer}")
 
+                ipsec['dhcp_interfaces'].add(dhcp_interface)
+
                 address = get_dhcp_address(dhcp_interface)
                 count = 0
                 while not address and count < dhcp_wait_attempts:
@@ -391,7 +420,7 @@ def verify(ipsec):
                     sleep(dhcp_wait_sleep)
 
                 if not address:
-                    ipsec['dhcp_no_address'][peer] = dhcp_interface
+                    ipsec['dhcp_no_address'][f'peer_{peer}'] = dhcp_interface
                     print(f"Failed to get address from dhcp-interface on site-to-site peer {peer} -- skipped")
                     continue
 
@@ -492,9 +521,9 @@ def generate(ipsec):
         render(charon_conf, 'ipsec/charon.j2', {'install_routes': default_install_routes})
         return
 
-    if ipsec['dhcp_no_address']:
+    if ipsec['dhcp_interfaces']:
         with open(DHCP_HOOK_IFLIST, 'w') as f:
-            f.write(" ".join(ipsec['dhcp_no_address'].values()))
+            f.write(" ".join(ipsec['dhcp_interfaces']))
     elif os.path.exists(DHCP_HOOK_IFLIST):
         os.unlink(DHCP_HOOK_IFLIST)
 
@@ -511,13 +540,23 @@ def generate(ipsec):
 
     if 'remote_access' in ipsec and 'connection' in ipsec['remote_access']:
         for rw, rw_conf in ipsec['remote_access']['connection'].items():
+            if f'ra_{rw}' in ipsec['dhcp_no_address']:
+                continue
+
+            local_ip = ''
+            if 'local_address' in rw_conf:
+                local_ip = rw_conf['local_address']
+            elif 'dhcp_interface' in rw_conf:
+                local_ip = get_dhcp_address(rw_conf['dhcp_interface'])
+
+            ipsec['remote_access']['connection'][rw]['local_address'] = local_ip
 
             if 'authentication' in rw_conf and 'x509' in rw_conf['authentication']:
                 generate_pki_files_x509(ipsec['pki'], rw_conf['authentication']['x509'])
 
     if 'site_to_site' in ipsec and 'peer' in ipsec['site_to_site']:
         for peer, peer_conf in ipsec['site_to_site']['peer'].items():
-            if peer in ipsec['dhcp_no_address']:
+            if f'peer_{peer}' in ipsec['dhcp_no_address']:
                 continue
 
             if peer_conf['authentication']['mode'] == 'x509':
diff --git a/src/etc/dhcp/dhclient-exit-hooks.d/99-ipsec-dhclient-hook b/src/etc/dhcp/dhclient-exit-hooks.d/99-ipsec-dhclient-hook
index e6edc1ac3..ebb100e8b 100755
--- a/src/etc/dhcp/dhclient-exit-hooks.d/99-ipsec-dhclient-hook
+++ b/src/etc/dhcp/dhclient-exit-hooks.d/99-ipsec-dhclient-hook
@@ -14,69 +14,32 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-if [ "$reason" == "REBOOT" ] || [ "$reason" == "EXPIRE" ]; then
-    return 0
-fi
-
-DHCP_HOOK_IFLIST="/tmp/ipsec_dhcp_waiting"
+DHCP_HOOK_IFLIST="/tmp/ipsec_dhcp_interfaces"
 
-if [ -f $DHCP_HOOK_IFLIST ] && [ "$reason" == "BOUND" ]; then
-    if grep -qw $interface $DHCP_HOOK_IFLIST; then
-        sudo rm $DHCP_HOOK_IFLIST
-        sudo /usr/libexec/vyos/conf_mode/vpn_ipsec.py
-        return 0
-    fi
+if ! { [ -f $DHCP_HOOK_IFLIST ] && grep -qw $interface $DHCP_HOOK_IFLIST; }; then
+    exit 0
 fi
 
-if [ "$old_ip_address" == "$new_ip_address" ] && [ "$reason" == "BOUND" ]; then
-    return 0
+# Re-generate the config on the following events:
+# - BOUND: always re-generate
+# - RENEW: re-generate if the IP address changed
+# - REBIND: re-generate if the IP address changed
+if [ "$reason" == "RENEW" ] || [ "$reason" == "REBIND" ]; then
+    if [ "$old_ip_address" == "$new_ip_address" ]; then
+        exit 0
+    fi
+elif [ "$reason" != "BOUND" ]; then
+    exit 0
 fi
 
-python3 - <<PYEND
-import os
-import re
-
-from vyos.utils.process import call
-from vyos.utils.process import cmd
-from vyos.utils.file import read_file
-from vyos.utils.file import write_file
-
-SWANCTL_CONF="/etc/swanctl/swanctl.conf"
-
-def ipsec_down(ip_address):
-    # This prevents the need to restart ipsec and kill all active connections, only the stale connection is closed
-    status = cmd('sudo ipsec statusall')
-    connection_name = None
-    for line in status.split("\n"):
-        if line.find(ip_address) > 0:
-            regex_match = re.search(r'(peer_[^:\[]+)', line)
-            if regex_match:
-                connection_name = regex_match[1]
-                break
-    if connection_name:
-        call(f'sudo ipsec down {connection_name}')
+# Best effort wait for any active commit to finish
+sudo python3 - <<PYEND
+from vyos.utils.commit import wait_for_commit_lock
 
 if __name__ == '__main__':
-    interface = os.getenv('interface')
-    new_ip = os.getenv('new_ip_address')
-    old_ip = os.getenv('old_ip_address')
-
-    if os.path.exists(SWANCTL_CONF):
-        conf_lines = read_file(SWANCTL_CONF)
-        found = False
-        to_match = f'# dhcp:{interface}'
-
-        for i, line in enumerate(conf_lines):
-            if line.find(to_match) > 0:
-                conf_lines[i] = line.replace(old_ip, new_ip)
-                found = True
-
-        if found:
-            write_file(SWANCTL_CONF, conf_lines)
-            ipsec_down(old_ip)
-            call('sudo ipsec rereadall')
-            call('sudo ipsec reload')
-            call('sudo swanctl -q')
-
+    wait_for_commit_lock()
     exit(0)
 PYEND
+
+# Now re-generate the config
+sudo /usr/libexec/vyos/conf_mode/vpn_ipsec.py