ParagonIE_Sodium_Core_AEGIS_State256::enc( string $xi ): string

163    public function enc($xi)164    {165        if (ParagonIE_Sodium_Core_Util::strlen($xi) !== 16) {166            throw new SodiumException('Input must be an AES block in size');167        }168        // z = S1 ^ S4 ^ S5 ^ (S2 & S3)169        $z = $this->state[1]170            ^ $this->state[4]171            ^ $this->state[5]172            ^ ParagonIE_Sodium_Core_Util::andStrings($this->state[2], $this->state[3]);173        $this->update($xi);174        return $xi ^ $z;175    }