plugins/mod_mimicking.lua

   1 -- Prosody IM
   2 -- Copyright (C) 2012 Florian Zeitz
   3 -- Copyright (C) 2019 Kim Alvefur
   4 --
   5 -- This project is MIT/X11 licensed. Please see the
   6 -- COPYING file in the source package for more information.
   7 --
   8
   9 local encodings = require "util.encodings";
  10 assert(encodings.confusable, "This module requires that Prosody be built with ICU");
  11 local skeleton = encodings.confusable.skeleton;
  12
  13 local usage = require "util.prosodyctl".show_usage;
  14 local usermanager = require "core.usermanager";
  15 local storagemanager = require "core.storagemanager";
  16
  17 local skeletons
  18 function module.load()
  19         if module.host ~= "*" then
  20                 skeletons = module:open_store("skeletons");
  21         end
  22 end
  23
  24 module:hook("user-registered", function(user)
  25         local skel = skeleton(user.username);
  26         local ok, err = skeletons:set(skel, { username = user.username });
  27         if not ok then
  28                 module:log("error", "Unable to store mimicry data (%q => %q): %s", user.username, skel, err);
  29         end
  30 end);
  31
  32 module:hook("user-deleted", function(user)
  33         local skel = skeleton(user.username);
  34         local ok, err = skeletons:set(skel, nil);
  35         if not ok and err then
  36                 module:log("error", "Unable to clear mimicry data (%q): %s", skel, err);
  37         end
  38 end);
  39
  40 module:hook("user-registering", function(user)
  41         local existing, err = skeletons:get(skeleton(user.username));
  42         if existing then
  43                 module:log("debug", "Attempt to register username '%s' which could be confused with '%s'", user.username, existing.username);
  44                 user.allowed = false;
  45         elseif err then
  46                 module:log("error", "Unable to check if new username '%s' can be confused with any existing user: %s", err);
  47         end
  48 end);
  49
  50 function module.command(arg)
  51         if (arg[1] ~= "bootstrap" or not arg[2]) then
  52                 usage("mod_mimicking bootstrap <host>", "Initialize username mimicry database");
  53                 return;
  54         end
  55
  56         local host = arg[2];
  57
  58         local host_session = prosody.hosts[host];
  59         if not host_session then
  60                 return "No such host";
  61         end
  62
  63         storagemanager.initialize_host(host);
  64         usermanager.initialize_host(host);
  65
  66         skeletons = storagemanager.open(host, "skeletons");
  67
  68         local count = 0;
  69         for user in usermanager.users(host) do
  70                 local skel = skeleton(user);
  71                 local existing, err = skeletons:get(skel);
  72                 if existing and existing.username ~= user then
  73                         module:log("warn", "Existing usernames '%s' and '%s' are confusable", existing.username, user);
  74                 elseif err then
  75                         module:log("error", "Error checking for existing mimicry data (%q = %q): %s", user, skel, err);
  76                 end
  77                 local ok, err = skeletons:set(skel, { username = user });
  78                 if ok then
  79                         count = count + 1;
  80                 elseif err then
  81                         module:log("error", "Unable to store mimicry data (%q => %q): %s", user, skel, err);
  82                 end
  83         end
  84         module:log("info", "%d usernames indexed", count);
  85 end