Merge pull request #43 from Sweil/regex-rights-management

New rights management method: regex

config

@@ -96,13 +96,19 @@ http_password_parameter =
 
 [rights]
 # Rights management method
-# Value: None | owner_only | owner_write | from_file
+# Value: None | owner_only | owner_write | from_file | regex
 type = None
 
 # File for rights management from_file
 file = ~/.config/radicale/rights
 
 
+# File for rights management regex
+regex_file =~/.config/radicale/regex
+# use this as alternative method
+regex_secondary = owner_only
+
+
 [storage]
 # Storage backend
 # Value: filesystem | database

radicale/config.py

@@ -74,7 +74,9 @@ INITIAL_CONFIG = {
         "http_password_parameter": ""},
     "rights": {
         "type": "None",
-        "file": ""},
+        "file": "",
+        "regex_file": "",
+        "regex_secondary": "owner_only"},
     "storage": {
         "type": "filesystem",
         "filesystem_folder": os.path.expanduser(

radicale/rights/regex.py

@@ -0,0 +1,160 @@
+# -*- coding: utf-8 -*-
+#
+# This file is part of Radicale Server - Calendar Server
+# Copyright © 2012-2013 Guillaume Ayoub
+#
+# This library is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Radicale.  If not, see <http://www.gnu.org/licenses/>.
+
+"""
+Regex-based rights.
+
+You can define an secondary rights management method. If not, it will use
+"owner_only", which implies the owners have all rights on their collections.
+Secondary rights management method is specified in the config (section
+"right", key "regex_secondary").
+
+Regexes are read from a file whose name is specified in the config (section
+"right", key "regex_file").
+
+Test string for regex is "user|collection" per default, because "|" is
+not allowed in an URL. You may set this string per rule, using Python's
+ConfigParser interpolation: %(user)s and %(collection)s
+In fact you may also set user/collection to a fixed value per rule. But you 
+should consider using a secondary rights management method (e.g. "from_file").
+
+
+Section names are only used for naming the rule.
+Leading or Ending "/"s are trimmed from collection names.
+
+Example:
+
+# This means all users starting with "admin" may read any collection
+[admin]
+regex: ^admin.*\|.+?$
+permission: r
+
+# This means all users may read and write any collection starting with public.
+# We do so by just not testing against the user string.
+[public]
+glue: %(collection)s
+regex: ^public(/.+)?$
+permission: rw
+
+# A little more complex:
+# Give read access to users from a domain for all collections of all the users:
+[domain-wide-access]
+regex:  ^.+@(.+)\|.+@\1(/.+)?$
+permission: r
+
+
+"""
+
+import os.path
+import re
+
+from radicale import config, log, rights
+# Manage Python2/3 different modules
+# pylint: disable=F0401
+try:
+    from configparser import (
+        ConfigParser as ConfigParser, NoSectionError, NoOptionError)
+except ImportError:
+    from ConfigParser import (
+        ConfigParser as ConfigParser, NoSectionError, NoOptionError)
+# pylint: enable=F0401
+
+
+FILENAME = (
+    os.path.expanduser(config.get("rights", "regex_file")) or
+    log.LOGGER.error("No file name configured for rights type 'regex'"))
+    
+    
+def _read_regex(user, collection):
+    """Load regex from file."""
+    regex = ConfigParser({'user': user, 'collection': collection})
+    if not regex.read(FILENAME):
+        log.LOGGER.error(
+            "File '%s' not found for rights management type 'regex'" % FILENAME)
+    return regex
+    
+def _read_from_sections(user, collection, perm):
+    """Get regex sections."""    
+    regex = _read_regex(user, collection)
+    try:  
+        for section in regex.sections():
+            if _matches_section(user, collection, section):
+                if perm in regex.get(section, "permission"):
+                    return True
+    except (NoSectionError, NoOptionError):
+        return False
+    return False
+    
+def _matches_section(user, collection, section):
+    """Regex section against user and collection"""
+    log.LOGGER.debug("Reading regex from file %s" % FILENAME)
+    regex = _read_regex(user, collection)
+    log.LOGGER.debug("Match against section '%s'" % section)
+
+    try:
+        test = regex.get(section, 'glue')
+    except (NoOptionError):
+        test = user+'|'+collection;
+    
+    try: 
+        match = re.match(regex.get(section, 'regex'), test)
+        if match:
+            return True;
+        log.LOGGER.debug("Test-String '%s' does not match against '%s' from section '%s'" % \
+            (test, regex.get(section, 'regex'), section))
+    except (NoSectionError, NoOptionError):
+        return False
+    return False
+    
+    
+
+def _get_secondary():
+    """Get secondary rights management method"""
+    try:  
+        secondary = config.get("rights", "regex_secondary")
+        if not secondary or secondary == None:
+            secondary = 'owner_only'
+        
+        root_module = __import__(
+            "rights.%s" % secondary, globals=globals(), level=2)
+        module = getattr(root_module, secondary)
+        return module
+    except (ImportError, NoSectionError, NoOptionError):
+        return None
+    
+
+def read_authorized(user, collection):
+    """Check if the user is allowed to read the collection."""
+    if user is None:
+        return False
+    elif _get_secondary() != None and _get_secondary().read_authorized(user, collection):
+        return True
+    else:
+        return _read_from_sections(
+            user, collection.url.rstrip("/") or "/", "r")
+
+
+def write_authorized(user, collection):
+    """Check if the user is allowed to write the collection."""
+    if user is None:
+        return False
+    elif _get_secondary() != None and _get_secondary().write_authorized(user, collection):
+        return True
+    else:
+        return _read_from_sections(
+            user, collection.url.rstrip("/") or "/", "w")