feature: the router has a two-level CA with an optional offline root, issuing CAs for P2S, site-to-site and general use, templates, published certificates and CRLs and an ACME server, site-to-site connections authenticate with certificates, and setup installs Caddy from Ubuntu or Caddy's repository.

debian-package/src/usr/lib/vpn-router/setup

@@ -22,6 +22,7 @@ import os
 import pathlib
 import re
 import secrets
+import shutil
 import socket
 import subprocess
 import sys
@@ -33,8 +34,9 @@ import ldap
 
 import vpnrouter
 import vpnrouter_ldap
+import vpnrouter_pki
 import vpnrouter_users
-from vpnrouter import fail
+from vpnrouter import fail, warn
 
 BEFORE_RULES = pathlib.Path('/etc/ufw/before.rules')
 UFW_DEFAULTS = pathlib.Path('/etc/default/ufw')
@@ -72,6 +74,15 @@ CADDYFILE   = pathlib.Path('/etc/caddy/vpn-router.Caddyfile')
 CADDY_UNIT  = 'caddy.service'
 CADDY_GROUP = 'caddy'
 
+#: The unit that installs Caddy from https.caddy_source with vpn-router-caddy, outside setup.
+CADDY_INSTALL_UNIT = 'vpn-router-caddy.service'
+
+#: The certificates and keys of the issuing CAs behind Caddy's ACME server, <name>/cert.pem and key.pem.
+CADDY_PKI_DIR = pathlib.Path('/etc/caddy/vpn-router-pki')
+
+#: The timer of vpn-router-ca maintain, which keeps the CRLs fresh.
+PKI_TIMER = 'vpn-router-pki.timer'
+
 FILTER_ANCHOR = '# End required lines'
 
 #: Configuration options left out wherever the configuration is shown.
@@ -266,16 +277,21 @@ def filter_block(ctx):
             '# METRICS RULES END',
         ]
 
-    # Let's Encrypt reaches the HTTP challenge on the external interface; the HTTPS ports are open on both.
+    # Let's Encrypt reaches the HTTP challenge on the external interface, and the CA files published on port 80 are
+    # read on both; the HTTPS ports are open on both.
     if vpnrouter.https_ready(ctx) and interfaces:
-        ports = [port for wanted, port in ((ctx['web_enabled'], ctx['https_web_port']),
+        publish = ctx['pki_publish']
+        ports = [port for wanted, port in ((ctx['web_enabled'] or 'https' in publish or ctx['pki_acme'],
+                                            ctx['https_web_port']),
                                            (MANAGER.exists(), ctx['https_manager_port']),
-                                           (vpnrouter.metrics_ready(ctx), ctx['metrics_https_port'])) if wanted]
+                                           (vpnrouter.metrics_ready(ctx), ctx['metrics_https_port']),
+                                           ('http-80' in publish, vpnrouter.ACME_HTTP_PORT),
+                                           ('https-default' in publish, vpnrouter.HTTPS_DEFAULT_PORT)) if wanted]
         lines += [
             '',
             '# HTTPS RULES START',
             *([f'-A ufw-before-input -i {ctx["wan_iface"]} -p tcp --dport {vpnrouter.ACME_HTTP_PORT} -j ACCEPT']
-              if ctx['wan_iface'] else []),
+              if ctx['wan_iface'] and 'http-80' not in publish else []),
             *(f'-A ufw-before-input -i {name} -p tcp --dport {port} -j ACCEPT' for name in interfaces for port in ports),
             '# HTTPS RULES END',
         ]
@@ -528,13 +544,20 @@ def manage_openvpn(ctx, changed):
         run(['systemctl', 'restart', unit], check=False)
 
 
-def manage_caddy(ctx):
+def manage_caddy(cfg, ctx):
     """Run Caddy, the HTTPS proxy of the web service, the Router Manager and the metrics service, while HTTPS is ready, and stop it when not.
 
     CADDYFILE serves the web service on https.web_port, while the manager is installed the
     manager on https.manager_port, and while metrics are enabled the metrics service on
     metrics.https_port, all for wan.local_fqdn with a certificate from Let's Encrypt, and all
-    calling the service on its loopback address.
+    calling the service on its loopback address. It also serves the CA files of
+    vpnrouter_pki.PUBLISH_DIR at /pki/ on the endpoints of pki.publish that are Caddy's, and an
+    ACME server at /acme/<name>/ on https.web_port for each issuing CA with acme and a
+    certificate, whose certificate and key are copied to CADDY_PKI_DIR.
+
+    Caddy is installed by CADDY_INSTALL_UNIT, outside setup, when it is missing or when
+    https.caddy_source is upstream and Caddy's repository is not configured; the unit restarts
+    setup, whose next run serves with it.
     """
     if not vpnrouter.https_ready(ctx):
         vpnrouter.remove(CADDYFILE)
@@ -542,16 +565,42 @@ def manage_caddy(ctx):
             run(['systemctl', 'disable', '--now', CADDY_UNIT], check=False)
         return
 
+    source = cfg['https']['caddy_source']
+    if shutil.which('caddy') is None or (source == 'upstream' and not vpnrouter.CADDY_APT_SOURCE.is_file()):
+        run(['systemctl', 'start', '--no-block', CADDY_INSTALL_UNIT], check=False)
+        warn(f'Caddy is installed from the {source} source by {CADDY_INSTALL_UNIT}, which runs setup again')
+        return
+    if source == 'ubuntu' and vpnrouter.CADDY_APT_SOURCE.is_file():
+        warn("https.caddy_source ubuntu is ignored: Caddy's repository is configured, and Caddy stays upstream's")
+
     try:
         group = grp.getgrnam(CADDY_GROUP).gr_gid
     except KeyError:
         fail(f'the group {CADDY_GROUP} does not exist; is the caddy package installed?')
-    caddy_ctx = dict(ctx, manager_port=manager_port() if MANAGER.exists() else 0)
+    acme = [name for name in ctx['pki_acme'] if vpnrouter_pki.ready(name)]
+    copied = False
+    for folder in (CADDY_PKI_DIR.iterdir() if CADDY_PKI_DIR.is_dir() else []):
+        if folder.name not in acme:
+            shutil.rmtree(folder)
+    for name in acme:
+        folder = CADDY_PKI_DIR / name
+        for path in (CADDY_PKI_DIR, folder):
+            path.mkdir(mode=0o750, exist_ok=True)
+            os.chown(path, 0, group)
+        for file in ('cert.pem', 'key.pem'):
+            copied |= vpnrouter.install_file(vpnrouter_pki.CA_DIR / name / file, folder / file, 0o640)
+            os.chown(folder / file, 0, group)
+    authorities = vpnrouter.issuing_cas(cfg)
+    caddy_ctx = dict(ctx, manager_port=manager_port() if MANAGER.exists() else 0,
+                     pki_publish_dir=str(vpnrouter_pki.PUBLISH_DIR),
+                     acme_cas=[{'id': name, 'name': authorities[name]['name'].strip(),
+                                'cert': str(CADDY_PKI_DIR / name / 'cert.pem'),
+                                'key': str(CADDY_PKI_DIR / name / 'key.pem')} for name in acme])
     changed = vpnrouter.render(vpnrouter._jinja_env(), caddy_ctx, 'Caddyfile.j2', CADDYFILE, 0o640)
     os.chown(CADDYFILE, 0, group)
     if not unit_is_active(CADDY_UNIT):
         run(['systemctl', 'enable', '--now', CADDY_UNIT], check=False)
-    elif changed:
+    elif changed or copied:
         run(['systemctl', 'reload', CADDY_UNIT], check=False)
 
 
@@ -744,7 +793,9 @@ def main():
     progress('running', 'OpenVPN')
     manage_openvpn(ctx, changed)
     progress('running', 'HTTPS proxy')
-    manage_caddy(ctx)
+    manage_caddy(cfg, ctx)
+    progress('running', 'PKI timer')
+    run(['systemctl', 'enable', '--now', PKI_TIMER], check=False)
 
     if 'resolved' in changed:
         progress('running', 'resolver')