plugins/mod_auth_internal_hashed.lua

   1 -- Prosody IM
   2 -- Copyright (C) 2008-2010 Matthew Wild
   3 -- Copyright (C) 2008-2010 Waqas Hussain
   4 -- Copyright (C) 2010 Jeff Mitchell
   5 --
   6 -- This project is MIT/X11 licensed. Please see the
   7 -- COPYING file in the source package for more information.
   8 --
   9
  10 local max = math.max;
  11
  12 local scram_hashers = require "util.sasl.scram".hashers;
  13 local usermanager = require "core.usermanager";
  14 local generate_uuid = require "util.uuid".generate;
  15 local new_sasl = require "util.sasl".new;
  16 local hex = require"util.hex";
  17 local to_hex, from_hex = hex.to, hex.from;
  18
  19 local log = module._log;
  20 local host = module.host;
  21
  22 local accounts = module:open_store("accounts");
  23
  24 local hash_name = module:get_option_string("password_hash", "SHA-1");
  25 local get_auth_db = assert(scram_hashers[hash_name], "SCRAM-"..hash_name.." not supported by SASL library");
  26 local scram_name = "scram_"..hash_name:gsub("%-","_"):lower();
  27
  28 -- Default; can be set per-user
  29 local default_iteration_count = 4096;
  30
  31 -- define auth provider
  32 local provider = {};
  33
  34 function provider.test_password(username, password)
  35         log("debug", "test password for user '%s'", username);
  36         local credentials = accounts:get(username) or {};
  37
  38         if credentials.password ~= nil and string.len(credentials.password) ~= 0 then
  39                 if credentials.password ~= password then
  40                         return nil, "Auth failed. Provided password is incorrect.";
  41                 end
  42
  43                 if provider.set_password(username, credentials.password) == nil then
  44                         return nil, "Auth failed. Could not set hashed password from plaintext.";
  45                 else
  46                         return true;
  47                 end
  48         end
  49
  50         if credentials.iteration_count == nil or credentials.salt == nil or string.len(credentials.salt) == 0 then
  51                 return nil, "Auth failed. Stored salt and iteration count information is not complete.";
  52         end
  53
  54         local valid, stored_key, server_key = get_auth_db(password, credentials.salt, credentials.iteration_count);
  55
  56         local stored_key_hex = to_hex(stored_key);
  57         local server_key_hex = to_hex(server_key);
  58
  59         if valid and stored_key_hex == credentials.stored_key and server_key_hex == credentials.server_key then
  60                 return true;
  61         else
  62                 return nil, "Auth failed. Invalid username, password, or password hash information.";
  63         end
  64 end
  65
  66 function provider.set_password(username, password)
  67         log("debug", "set_password for username '%s'", username);
  68         local account = accounts:get(username);
  69         if account then
  70                 account.salt = generate_uuid();
  71                 account.iteration_count = max(account.iteration_count or 0, default_iteration_count);
  72                 local valid, stored_key, server_key = get_auth_db(password, account.salt, account.iteration_count);
  73                 local stored_key_hex = to_hex(stored_key);
  74                 local server_key_hex = to_hex(server_key);
  75
  76                 account.stored_key = stored_key_hex
  77                 account.server_key = server_key_hex
  78
  79                 account.password = nil;
  80                 return accounts:set(username, account);
  81         end
  82         return nil, "Account not available.";
  83 end
  84
  85 function provider.user_exists(username)
  86         local account = accounts:get(username);
  87         if not account then
  88                 log("debug", "account not found for username '%s'", username);
  89                 return nil, "Auth failed. Invalid username";
  90         end
  91         return true;
  92 end
  93
  94 function provider.users()
  95         return accounts:users();
  96 end
  97
  98 function provider.create_user(username, password)
  99         if password == nil then
 100                 return accounts:set(username, {});
 101         end
 102         local salt = generate_uuid();
 103         local valid, stored_key, server_key = get_auth_db(password, salt, default_iteration_count);
 104         local stored_key_hex = to_hex(stored_key);
 105         local server_key_hex = to_hex(server_key);
 106         return accounts:set(username, {
 107                 stored_key = stored_key_hex, server_key = server_key_hex,
 108                 salt = salt, iteration_count = default_iteration_count
 109         });
 110 end
 111
 112 function provider.delete_user(username)
 113         return accounts:set(username, nil);
 114 end
 115
 116 function provider.get_sasl_handler()
 117         local testpass_authentication_profile = {
 118                 plain_test = function(_, username, password, realm)
 119                         return usermanager.test_password(username, realm, password), true;
 120                 end,
 121                 [scram_name] = function(_, username)
 122                         local credentials = accounts:get(username);
 123                         if not credentials then return; end
 124                         if credentials.password then
 125                                 if provider.set_password(username, credentials.password) == nil then
 126                                         return nil, "Auth failed. Could not set hashed password from plaintext.";
 127                                 end
 128                                 credentials = accounts:get(username);
 129                                 if not credentials then return; end
 130                         end
 131
 132                         local stored_key, server_key = credentials.stored_key, credentials.server_key;
 133                         local iteration_count, salt = credentials.iteration_count, credentials.salt;
 134                         stored_key = stored_key and from_hex(stored_key);
 135                         server_key = server_key and from_hex(server_key);
 136                         return stored_key, server_key, iteration_count, salt, true;
 137                 end
 138         };
 139         return new_sasl(host, testpass_authentication_profile);
 140 end
 141
 142 module:provides("auth", provider);
 143