Append client IP to subscribe log entries when available.

Add shared helpers to read the remote address from CGI environment
variables and append it to membership add/delete/change syslog lines
when present, without duplicating addresses already in the whence field.

Author: jaredmauch

Mailman/MailList.py

@@ -1185,8 +1185,9 @@ def ApprovedAddMember(self, userdesc, ack=None, admin_notif=None, text='',
         if isinstance(name, bytes):
             name = name.decode(Utils.GetCharSet(lang))
 
+        log_whence = Utils.append_remote_for_log(whence or '')
         syslog('subscribe', '%s: new%s %s, %s', self.internal_name(),
-               kind, formataddr((name, email)), whence)
+               kind, formataddr((name, email)), log_whence)
         if ack:
             lang = self.preferred_language
             otrans = i18n.get_translation()
@@ -1255,6 +1256,7 @@ def ApprovedDeleteMember(self, name, whence=None,
             whence = "; %s" % whence
         else:
             whence = ""
+        whence = Utils.append_remote_for_log(whence)
         syslog('subscribe', '%s: deleted %s%s',
                self.internal_name(), name, whence)
 
@@ -1396,8 +1398,11 @@ def ApprovedChangeMemberAddress(self, oldaddr, newaddr, globally):
 
     def log_and_notify_admin(self, oldaddr, newaddr):
         """Log member address change and notify admin if requested."""
-        syslog('subscribe', '%s: changed member address from %s to %s',
-               self.internal_name(), oldaddr, newaddr)
+        log_suffix = Utils.append_remote_for_log('')
+        if log_suffix:
+            log_suffix = ' %s' % log_suffix
+        syslog('subscribe', '%s: changed member address from %s to %s%s',
+               self.internal_name(), oldaddr, newaddr, log_suffix)
         if self.admin_notify_mchanges:
             lang = self.preferred_language
             otrans = i18n.get_translation()

Mailman/Utils.py

@@ -497,6 +497,26 @@ def ValidateEmail(s):
 # line in the mailman error log. (TK: advisory by Moritz Naumann)
 CRNLpat = re.compile(r'[^\x21-\x7e]')
 
+def get_remote_addr():
+    """Return the client IP from CGI environment, or None if unavailable."""
+    return (os.environ.get('HTTP_FORWARDED_FOR') or
+            os.environ.get('HTTP_X_FORWARDED_FOR') or
+            os.environ.get('REMOTE_ADDR'))
+
+
+def append_remote_for_log(whence=''):
+    """Append client IP to a subscribe-log whence string when available."""
+    remote = get_remote_addr()
+    if not remote:
+        return whence or ''
+    whence = whence or ''
+    if remote in whence:
+        return whence
+    if whence:
+        return '%s %s' % (whence, remote)
+    return remote
+
+
 def GetPathPieces(envar='PATH_INFO'):
     path = os.environ.get(envar)
     if path: