Mercurial > prosody-modules
view mod_auth_token/token_auth_utils.lib.lua @ 5616:59d5fc50f602
mod_http_oauth2: Implement refresh token rotation
Makes refresh tokens one-time-use, handing out a new refresh token with
each access token. Thus if a refresh token is stolen and used by an
attacker, the next time the legitimate client tries to use the previous
refresh token, it will not work and the attack will be noticed. If the
attacker does not use the refresh token, it becomes invalid after the
legitimate client uses it.
This behavior is recommended by draft-ietf-oauth-security-topics
author | Kim Alvefur <zash@zash.se> |
---|---|
date | Sun, 23 Jul 2023 02:56:08 +0200 |
parents | 0fb12a4b6106 |
children |
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local base64 = require "util.encodings".base64; local hmac = require "openssl.hmac"; local luatz = require "luatz"; local otp = require "otp"; local DIGEST_TYPE = "SHA256"; local OTP_DEVIATION = 1; local OTP_DIGITS = 8; local OTP_INTERVAL = 30; local nonce_cache = {}; local function check_nonce(jid, otp_value, nonce) -- We cache all nonces used per OTP, to ensure that a token cannot be used -- more than once. -- -- We assume that the OTP is valid in the current time window. This is the -- case because we only call check_nonce *after* the OTP has been verified. -- -- We only store one OTP per JID, so if a new OTP comes in, we wipe the -- previous OTP and its cached nonces. if nonce_cache[jid] == nil or nonce_cache[jid][otp_value] == nil then nonce_cache[jid] = {} nonce_cache[jid][otp_value] = {} nonce_cache[jid][otp_value][nonce] = true return true; end if nonce_cache[jid][otp_value][nonce] == true then return false; else nonce_cache[jid][otp_value][nonce] = true; return true; end end local function verify_token(username, password, otp_seed, token_secret, log) local totp = otp.new_totp_from_key(otp_seed, OTP_DIGITS, OTP_INTERVAL) local token = string.match(password, "(%d+) ") local otp_value = token:sub(1,8) local nonce = token:sub(9) local signature = base64.decode(string.match(password, " (.+)")) local jid = username.."@"..module.host if totp:verify(otp_value, OTP_DEVIATION, luatz.time()) then log("debug", "The TOTP was verified"); local hmac_ctx = hmac.new(token_secret, DIGEST_TYPE) if signature == hmac_ctx:final(otp_value..nonce..jid) then log("debug", "The key was verified"); if check_nonce(jid, otp_value, nonce) then log("debug", "The nonce was verified"); return true; end end end log("debug", "Verification failed"); return false; end return { OTP_DEVIATION = OTP_DIGITS, OTP_DIGITS = OTP_DIGITS, OTP_INTERVAL = OTP_INTERVAL, DIGEST_TYPE = DIGEST_TYPE, verify_token = verify_token; }