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 getAuthenticationDatabaseSHA1 = require "util.sasl.scram".getAuthenticationDatabaseSHA1;
  13 local usermanager = require "core.usermanager";
  14 local generate_uuid = require "util.uuid".generate;
  15 local new_sasl = require "util.sasl".new;
  16
  17 local log = module._log;
  18 local host = module.host;
  19
  20 local accounts = module:open_store("accounts");
  21
  22 local to_hex;
  23 do
  24         local function replace_byte_with_hex(byte)
  25                 return ("%02x"):format(byte:byte());
  26         end
  27         function to_hex(binary_string)
  28                 return binary_string:gsub(".", replace_byte_with_hex);
  29         end
  30 end
  31
  32 local from_hex;
  33 do
  34         local function replace_hex_with_byte(hex)
  35                 return string.char(tonumber(hex, 16));
  36         end
  37         function from_hex(hex_string)
  38                 return hex_string:gsub("..", replace_hex_with_byte);
  39         end
  40 end
  41
  42
  43 -- Default; can be set per-user
  44 local default_iteration_count = 4096;
  45
  46 -- define auth provider
  47 local provider = {};
  48
  49 function provider.test_password(username, password)
  50         log("debug", "test password for user '%s'", username);
  51         local credentials = accounts:get(username) or {};
  52
  53         if credentials.password ~= nil and string.len(credentials.password) ~= 0 then
  54                 if credentials.password ~= password then
  55                         return nil, "Auth failed. Provided password is incorrect.";
  56                 end
  57
  58                 if provider.set_password(username, credentials.password) == nil then
  59                         return nil, "Auth failed. Could not set hashed password from plaintext.";
  60                 else
  61                         return true;
  62                 end
  63         end
  64
  65         if credentials.iteration_count == nil or credentials.salt == nil or string.len(credentials.salt) == 0 then
  66                 return nil, "Auth failed. Stored salt and iteration count information is not complete.";
  67         end
  68
  69         local valid, stored_key, server_key = getAuthenticationDatabaseSHA1(password, credentials.salt, credentials.iteration_count);
  70
  71         local stored_key_hex = to_hex(stored_key);
  72         local server_key_hex = to_hex(server_key);
  73
  74         if valid and stored_key_hex == credentials.stored_key and server_key_hex == credentials.server_key then
  75                 return true;
  76         else
  77                 return nil, "Auth failed. Invalid username, password, or password hash information.";
  78         end
  79 end
  80
  81 function provider.set_password(username, password)
  82         log("debug", "set_password for username '%s'", username);
  83         local account = accounts:get(username);
  84         if account then
  85                 account.salt = generate_uuid();
  86                 account.iteration_count = max(account.iteration_count or 0, default_iteration_count);
  87                 local valid, stored_key, server_key = getAuthenticationDatabaseSHA1(password, account.salt, account.iteration_count);
  88                 local stored_key_hex = to_hex(stored_key);
  89                 local server_key_hex = to_hex(server_key);
  90
  91                 account.stored_key = stored_key_hex
  92                 account.server_key = server_key_hex
  93
  94                 account.password = nil;
  95                 return accounts:set(username, account);
  96         end
  97         return nil, "Account not available.";
  98 end
  99
 100 function provider.user_exists(username)
 101         local account = accounts:get(username);
 102         if not account then
 103                 log("debug", "account not found for username '%s'", username);
 104                 return nil, "Auth failed. Invalid username";
 105         end
 106         return true;
 107 end
 108
 109 function provider.users()
 110         return accounts:users();
 111 end
 112
 113 function provider.create_user(username, password)
 114         if password == nil then
 115                 return accounts:set(username, {});
 116         end
 117         local salt = generate_uuid();
 118         local valid, stored_key, server_key = getAuthenticationDatabaseSHA1(password, salt, default_iteration_count);
 119         local stored_key_hex = to_hex(stored_key);
 120         local server_key_hex = to_hex(server_key);
 121         return accounts:set(username, {stored_key = stored_key_hex, server_key = server_key_hex, salt = salt, iteration_count = default_iteration_count});
 122 end
 123
 124 function provider.delete_user(username)
 125         return accounts:set(username, nil);
 126 end
 127
 128 function provider.get_sasl_handler()
 129         local testpass_authentication_profile = {
 130                 plain_test = function(sasl, username, password, realm)
 131                         return usermanager.test_password(username, realm, password), true;
 132                 end,
 133                 scram_sha_1 = function(sasl, username, realm)
 134                         local credentials = accounts:get(username);
 135                         if not credentials then return; end
 136                         if credentials.password then
 137                                 usermanager.set_password(username, credentials.password, host);
 138                                 credentials = accounts:get(username);
 139                                 if not credentials then return; end
 140                         end
 141
 142                         local stored_key, server_key, iteration_count, salt = credentials.stored_key, credentials.server_key, credentials.iteration_count, credentials.salt;
 143                         stored_key = stored_key and from_hex(stored_key);
 144                         server_key = server_key and from_hex(server_key);
 145                         return stored_key, server_key, iteration_count, salt, true;
 146                 end
 147         };
 148         return new_sasl(host, testpass_authentication_profile);
 149 end
 150
 151 module:provides("auth", provider);
 152