support templated interface name and privkey path

1 files changed, 31 insertions, 22 deletions

diff --git a/wg-genconf.py b/wg-genconf.py
index adc81e9..3a8269b 100755
--- a/wg-genconf.py
+++ b/wg-genconf.py
@@ -8,8 +8,8 @@ import functools
 import io
 import ipaddress
 import os
-import pathlib
 import re
+import string
 import shutil
 import sys
 import tomllib
@@ -55,8 +55,9 @@ class Interface(collections.UserDict):
         'port',
         'fwmark',
 
-        'prefix',
         'file-prefix',
+        'name-format',
+        'privkey-path',
     ]
 
     def __init__(self, data, name, peer):
@@ -84,11 +85,15 @@ class Interface(collections.UserDict):
         return self.peer.network
 
     @functools.cached_property
-    def qualified_name(self):
-        name = f'{self.get('prefix', '')}{self.network.name}'
-        if self.name:
-            name += f'-{self.name}'
-        return name
+    def formatted_name(self):
+        return self.format_string(self.get('name-format', '$network$_if'))
+
+    def format_string(self, s):
+        return string.Template(s).substitute({
+            'network': self.network.name,
+            'peer': self.peer.name,
+            'if': self.name,
+            '_if' : f'-{self.name}' if self.name else ''})
 
 
 def deep_merge(d, src):
@@ -150,10 +155,10 @@ def expand_peerspecs(peer, peerspecs):
         for x in (
             auto_peerspecs(peer) if peerspec.get('auto') else [peerspec])]
 
-def gc_if_data(if_, privkeys):
+def gc_if_data(if_):
     if_data = {
-        'name': if_.qualified_name,
-        'privkey': privkeys.get(if_.network.name, 'FIXME'),
+        'name': if_.formatted_name,
+        'privkey': get_privkey(if_),
         'addrs': ipspecs_to_ips(
             if_.peer, if_.get('ips', ['{peer/-}']), interface=True),
         'port': if_.get('port'),
@@ -250,22 +255,22 @@ def buf_to_file(buf, path, mode=None):
         buf.seek(0)
         shutil.copyfileobj(buf, f)
 
-def create_if_files(if_, privkeys):
-    if_data = gc_if_data(if_, privkeys)
+def create_if_files(if_):
+    if_data = gc_if_data(if_)
     file_prefix = f'out/{if_.get('file-prefix', '')}'
 
     if if_.get('type') == 'systemd':
         buf_to_file(
             gc_if_systemd_netdev(if_data),
-            f'{file_prefix}{if_.qualified_name}.netdev',
+            f'{file_prefix}{if_.formatted_name}.netdev',
             mode=0o640)
         buf_to_file(
             gc_if_systemd_network(if_data),
-            f'{file_prefix}{if_.qualified_name}.network')
+            f'{file_prefix}{if_.formatted_name}.network')
     else:
         buf_to_file(
             gc_if_wgquick(if_data),
-            f'{file_prefix}{if_.qualified_name}.conf')
+            f'{file_prefix}{if_.formatted_name}.conf')
 
 def load_network_peer_interfaces(config, peer):
     ifs = peer.pop('if', {})
@@ -300,12 +305,17 @@ def load_networks(config):
         load_network_peers(config, net)
     return nets
 
-def load_privkeys():
-    privkeys = {}
-    for path in pathlib.Path.home().joinpath('.wg-genconf').glob('*.privkey'):
+@functools.cache
+def read_privkey(path):
+    try:
         with open(path, 'r') as f:
-            privkeys[path.stem] = f.read().rstrip()
-    return privkeys
+            return f.read().rstrip()
+    except OSError:
+        return 'FIXME'
+
+def get_privkey(if_):
+    return read_privkey(if_.format_string(os.path.expanduser(
+        if_.get('privkey-path', '~/.wg-genconf/${network}.privkey'))))
 
 def main():
     conf_file = sys.argv[1]
@@ -314,7 +324,6 @@ def main():
     with open(conf_file, 'rb') as f:
         config = tomllib.load(f)
     networks = load_networks(config)
-    privkeys = load_privkeys()
 
     if not config['peer'].get(peer_name):
         sys.exit(f"peer '{peer_name}' not configured")
@@ -326,6 +335,6 @@ def main():
             # config files, useful when an auto-peer interface is being
             # separately created
             if if_.get('file', True):
-                create_if_files(if_, privkeys)
+                create_if_files(if_)
 
 main()