ParagonIE_Sodium_Core_AEGIS_State128L::decPartial( string $cn ): string

138    public function decPartial($cn)139    {140        $len = ParagonIE_Sodium_Core_Util::strlen($cn);141 142        // z0 = S6 ^ S1 ^ (S2 & S3)143        $z0 = $this->state[6]144            ^ $this->state[1]145            ^ ParagonIE_Sodium_Core_Util::andStrings($this->state[2], $this->state[3]);146        // z1 = S2 ^ S5 ^ (S6 & S7)147        $z1 = $this->state[2]148            ^ $this->state[5]149            ^ ParagonIE_Sodium_Core_Util::andStrings($this->state[6], $this->state[7]);150 151        // t0, t1 = Split(ZeroPad(cn, 256), 128)152        $cn = str_pad($cn, 32, "\0", STR_PAD_RIGHT);153        $t0 = ParagonIE_Sodium_Core_Util::substr($cn, 0, 16);154        $t1 = ParagonIE_Sodium_Core_Util::substr($cn, 16, 16);155        // out0 = t0 ^ z0156        // out1 = t1 ^ z1157        $out0 = $t0 ^ $z0;158        $out1 = $t1 ^ $z1;159 160        // xn = Truncate(out0 || out1, |cn|)161        $xn = ParagonIE_Sodium_Core_Util::substr($out0 . $out1, 0, $len);162 163        // v0, v1 = Split(ZeroPad(xn, 256), 128)164        $padded = str_pad($xn, 32, "\0", STR_PAD_RIGHT);165        $v0 = ParagonIE_Sodium_Core_Util::substr($padded, 0, 16);166        $v1 = ParagonIE_Sodium_Core_Util::substr($padded, 16, 16);167        // Update(v0, v1)168        $this->update($v0, $v1);169 170        // return xn171        return $xn;172    }