1 -- Prosody IM

     2 -- Copyright (C) 2008-2017 Matthew Wild

     3 -- Copyright (C) 2008-2017 Waqas Hussain

     4 -- Copyright (C) 2008-2017 Kim Alvefur

     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 s_gsub = string.gsub;

    11 local random_bytes = require "util.random".bytes;

    12 local base64_encode = require "util.encodings".base64.encode;

    13 

    14 local b64url = { ["+"] = "-", ["/"] = "_", ["="] = "" };

    15 local function b64url_random(len)

    16 	return (s_gsub(base64_encode(random_bytes(len)), "[+/=]", b64url));

    17 end

    18 

    19 return {

    20 	short =  function () return b64url_random(6); end;

    21 	medium = function () return b64url_random(12); end;

    22 	long =   function () return b64url_random(24); end;

    23 	custom = function (size)

    24 		return function () return b64url_random(size); end;

    25 	end;

    26 }