Is it HMAC?
https://github.com/phalcon/cphalcon/blob/master/phalcon/http/cookie.zep#L301
https://docs.phalcon.io/en/3.4/crypt
Althrough there is commit which does have hmac implementation:
https://github.com/phalcon/cphalcon/commit/7ff31aa155e159e885241650d7e9796eecc93369#diff-70ac11989967ef7c9d25b4b435f0d1f3R201
But this is not present in the master?! Ping @sergeyklay for this..