pki: T5886: add support for ACME protocol (LetsEncrypt)

The "idea" of this PR is to add new CLI nodes under the pki subsystem to
activate ACME for any given certificate.

vyos@vyos# set pki certificate NAME acme
Possible completions:
+  domain-name          Domain Name
   email                Email address to associate with certificate
   listen-address       Local IPv4 addresses to listen on
   rsa-key-size         Size of the RSA key (default: 2048)
   url                  Remote URL (default:
                        https://acme-v02.api.letsencrypt.org/directory)

Users choose if the CLI based custom certificates are used
  set pki certificate EXAMPLE acme certificate <base64>
or if it should be generated via ACME.

The ACME server URL defaults to LetsEncrypt but can be changed to their staging
API for testing to not get blacklisted.
  set pki certificate EXAMPLE acme url https://acme-staging-v02.api.letsencrypt.org/directory

Certificate retrieval has a certbot --dry-run stage in verify() to see if it
can be generated.

After successful generation, the certificate is stored in under
/config/auth/letsencrypt. Once a certificate is referenced in the CLI (e.g. set
interfaces ethernet eth0 eapol certificate EXAMPLE) we call
vyos.config.get_config_dict() which will (if with_pki=True is set) blend in the
base64 encoded certificate into the JSON data structure normally used when
using a certificate set by the CLI.

Using this "design" does not need any change to any other code referencing the
PKI system, as the base64 encoded certificate is already there.

certbot renewal will call the PKI python script to trigger dependency updates.

(cherry picked from commit b8db1a9d7baf91b70c1b735e58710f1e2bc9fc7a)

# Conflicts:
#	debian/control

1 files changed, 10 insertions, 2 deletions

diff --git a/src/op_mode/pki.py b/src/op_mode/pki.py
index 6c854afb5..ad2c1ada0 100755
--- a/src/op_mode/pki.py
+++ b/src/op_mode/pki.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 #
-# Copyright (C) 2021-2023 VyOS maintainers and contributors
+# Copyright (C) 2021-2024 VyOS maintainers and contributors
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License version 2 or later as
@@ -25,6 +25,7 @@ from cryptography import x509
 from cryptography.x509.oid import ExtendedKeyUsageOID
 
 from vyos.config import Config
+from vyos.config import config_dict_mangle_acme
 from vyos.pki import encode_certificate, encode_public_key, encode_private_key, encode_dh_parameters
 from vyos.pki import get_certificate_fingerprint
 from vyos.pki import create_certificate, create_certificate_request, create_certificate_revocation_list
@@ -79,9 +80,14 @@ def get_config_certificate(name=None):
         if not conf.exists(base + ['private', 'key']) or not conf.exists(base + ['certificate']):
             return False
 
-    return conf.get_config_dict(base, key_mangling=('-', '_'),
+    pki = conf.get_config_dict(base, key_mangling=('-', '_'),
                                 get_first_key=True,
                                 no_tag_node_value_mangle=True)
+    if pki:
+        for certificate in pki:
+            pki[certificate] = config_dict_mangle_acme(certificate, pki[certificate])
+
+    return pki
 
 def get_certificate_ca(cert, ca_certs):
     # Find CA certificate for given certificate
@@ -1073,7 +1079,9 @@ if __name__ == '__main__':
                 show_crl(None if args.crl == 'all' else args.crl, args.pem)
             else:
                 show_certificate_authority()
+                print('\n')
                 show_certificate()
+                print('\n')
                 show_crl()
     except KeyboardInterrupt:
         print("Aborted")