ParagonIE_Sodium_File::box_seal( string $inputFile, string $outputFile, string $publicKey ): bool

177    public static function box_seal(178        $inputFile,179        $outputFile,180        #[\SensitiveParameter]181        $publicKey182    ) {183        /* Type checks: */184        if (!is_string($inputFile)) {185            throw new TypeError('Argument 1 must be a string, ' . gettype($inputFile) . ' given.');186        }187        if (!is_string($outputFile)) {188            throw new TypeError('Argument 2 must be a string, ' . gettype($outputFile) . ' given.');189        }190        if (!is_string($publicKey)) {191            throw new TypeError('Argument 3 must be a string, ' . gettype($publicKey) . ' given.');192        }193 194        /* Input validation: */195        if (self::strlen($publicKey) !== ParagonIE_Sodium_Compat::CRYPTO_BOX_PUBLICKEYBYTES) {196            throw new TypeError('Argument 3 must be CRYPTO_BOX_PUBLICKEYBYTES bytes');197        }198 199        if (!file_exists($inputFile)) {200            throw new SodiumException('Input file does not exist');201        }202        /** @var int $size */203        $size = filesize($inputFile);204        if (!is_int($size)) {205            throw new SodiumException('Could not obtain the file size');206        }207 208        /** @var resource $ifp */209        $ifp = fopen($inputFile, 'rb');210        if (!is_resource($ifp)) {211            throw new SodiumException('Could not open input file for reading');212        }213 214        /** @var resource $ofp */215        $ofp = @fopen($outputFile, 'wb');216        if (!is_resource($ofp)) {217            fclose($ifp);218            throw new SodiumException('Could not open output file for writing');219        }220 221        /** @var string $ephKeypair */222        $ephKeypair = ParagonIE_Sodium_Compat::crypto_box_keypair();223 224        /** @var string $msgKeypair */225        $msgKeypair = ParagonIE_Sodium_Compat::crypto_box_keypair_from_secretkey_and_publickey(226            ParagonIE_Sodium_Compat::crypto_box_secretkey($ephKeypair),227            $publicKey228        );229 230        /** @var string $ephemeralPK */231        $ephemeralPK = ParagonIE_Sodium_Compat::crypto_box_publickey($ephKeypair);232 233        /** @var string $nonce */234        $nonce = ParagonIE_Sodium_Compat::crypto_generichash(235            $ephemeralPK . $publicKey,236            '',237            24238        );239 240        /** @var int $firstWrite */241        $firstWrite = fwrite(242            $ofp,243            $ephemeralPK,244            ParagonIE_Sodium_Compat::CRYPTO_BOX_PUBLICKEYBYTES245        );246        if (!is_int($firstWrite)) {247            fclose($ifp);248            fclose($ofp);249            ParagonIE_Sodium_Compat::memzero($ephKeypair);250            throw new SodiumException('Could not write to output file');251        }252        if ($firstWrite !== ParagonIE_Sodium_Compat::CRYPTO_BOX_PUBLICKEYBYTES) {253            ParagonIE_Sodium_Compat::memzero($ephKeypair);254            fclose($ifp);255            fclose($ofp);256            throw new SodiumException('Error writing public key to output file');