<?php
if (class_exists('ParagonIE_Sodium_File', false)) {
return;
}
/**
* Class ParagonIE_Sodium_File
*/
class ParagonIE_Sodium_File extends ParagonIE_Sodium_Core_Util
{
/* PHP's default buffer size is 8192 for fread()/fwrite(). */
const BUFFER_SIZE = 8192;
/**
* Box a file (rather than a string). Uses less memory than
* ParagonIE_Sodium_Compat::crypto_box(), but produces
* the same result.
*
* @param string $inputFile Absolute path to a file on the filesystem
* @param string $outputFile Absolute path to a file on the filesystem
* @param string $nonce Number to be used only once
* @param string $keyPair ECDH secret key and ECDH public key concatenated
*
* @return bool
* @throws SodiumException
* @throws TypeError
*/
public static function box($inputFile, $outputFile, $nonce, $keyPair)
{
/* Type checks: */
if (!is_string($inputFile)) {
throw new TypeError('Argument 1 must be a string, ' . gettype($inputFile) . ' given.');
}
if (!is_string($outputFile)) {
throw new TypeError('Argument 2 must be a string, ' . gettype($outputFile) . ' given.');
}
if (!is_string($nonce)) {
throw new TypeError('Argument 3 must be a string, ' . gettype($nonce) . ' given.');
}
/* Input validation: */
if (!is_string($keyPair)) {
throw new TypeError('Argument 4 must be a string, ' . gettype($keyPair) . ' given.');
}
if (self::strlen($nonce) !== ParagonIE_Sodium_Compat::CRYPTO_BOX_NONCEBYTES) {
throw new TypeError('Argument 3 must be CRYPTO_BOX_NONCEBYTES bytes');
}
if (self::strlen($keyPair) !== ParagonIE_Sodium_Compat::CRYPTO_BOX_KEYPAIRBYTES) {
throw new TypeError('Argument 4 must be CRYPTO_BOX_KEYPAIRBYTES bytes');
}
/** @var int $size */
$size = filesize($inputFile);
if (!is_int($size)) {
throw new SodiumException('Could not obtain the file size');
}
/** @var resource $ifp */
$ifp = fopen($inputFile, 'rb');
if (!is_resource($ifp)) {
throw new SodiumException('Could not open input file for reading');
}
/** @var resource $ofp */
$ofp = fopen($outputFile, 'wb');
if (!is_resource($ofp)) {
fclose($ifp);
throw new SodiumException('Could not open output file for writing');
}
$res = self::box_encrypt($ifp, $ofp, $size, $nonce, $keyPair);
fclose($ifp);
fclose($ofp);
return $res;
}
/**
* Open a boxed file (rather than a string). Uses less memory than
* ParagonIE_Sodium_Compat::crypto_box_open(), but produces
* the same result.
*
* Warning: Does not protect against TOCTOU attacks. You should
* just load the file into memory and use crypto_box_open() if
* you are worried about those.
*
* @param string $inputFile
* @param string $outputFile
* @param string $nonce
* @param string $keypair
* @return bool
* @throws SodiumException
* @throws TypeError
*/
public static function box_open($inputFile, $outputFile, $nonce, $keypair)
{
/* Type checks: */
if (!is_string($inputFile)) {
throw new TypeError('Argument 1 must be a string, ' . gettype($inputFile) . ' given.');
}
if (!is_string($outputFile)) {
throw new TypeError('Argument 2 must be a string, ' . gettype($outputFile) . ' given.');
}
if (!is_string($nonce)) {
throw new TypeError('Argument 3 must be a string, ' . gettype($nonce) . ' given.');
}
if (!is_string($keypair)) {
throw new TypeError('Argument 4 must be a string, ' . gettype($keypair) . ' given.');
}
/* Input validation: */
if (self::strlen($nonce) !== ParagonIE_Sodium_Compat::CRYPTO_BOX_NONCEBYTES) {
throw new TypeError('Argument 4 must be CRYPTO_BOX_NONCEBYTES bytes');
}
if (self::strlen($keypair) !== ParagonIE_Sodium_Compat::CRYPTO_BOX_KEYPAIRBYTES) {
throw new TypeError('Argument 4 must be CRYPTO_BOX_KEYPAIRBYTES bytes');
}
/** @var int $size */
$size = filesize($inputFile);
if (!is_int($size)) {
throw new SodiumException('Could not obtain the file size');
}
/** @var resource $ifp */
$ifp = fopen($inputFile, 'rb');
if (!is_resource($ifp)) {
throw new SodiumException('Could not open input file for reading');
}
/** @var resource $ofp */
$ofp = fopen($outputFile, 'wb');
if (!is_resource($ofp)) {
fclose($ifp);
throw new SodiumException('Could not open output file for writing');
}
$res = self::box_decrypt($ifp, $ofp, $size, $nonce, $keypair);
fclose($ifp);
fclose($ofp);
try {
ParagonIE_Sodium_Compat::memzero($nonce);
ParagonIE_Sodium_Compat::memzero($ephKeypair);
} catch (SodiumException $ex) {
if (isset($ephKeypair)) {
unset($ephKeypair);
}
}
return $res;
}
/**
* Seal a file (rather than a string). Uses less memory than
* ParagonIE_Sodium_Compat::crypto_box_seal(), but produces
* the same result.
*
* @param string $inputFile Absolute path to a file on the filesystem
* @param string $outputFile Absolute path to a file on the filesystem
* @param string $publicKey ECDH public key
*
* @return bool
* @throws SodiumException
* @throws TypeError
*/
public static function box_seal($inputFile, $outputFile, $publicKey)
{
/* Type checks: */
if (!is_string($inputFile)) {
throw new TypeError('Argument 1 must be a string, ' . gettype($inputFile) . ' given.');
}
if (!is_string($outputFile)) {
throw new TypeError('Argument 2 must be a string, ' . gettype($outputFile) . ' given.');
}
if (!is_string($publicKey)) {
throw new TypeError('Argument 3 must be a string, ' . gettype($publicKey) . ' given.');
}
/* Input validation: */
if (self::strlen($publicKey) !== ParagonIE_Sodium_Compat::CRYPTO_BOX_PUBLICKEYBYTES) {
throw new TypeError('Argument 3 must be CRYPTO_BOX_PUBLICKEYBYTES bytes');
}
/** @var int $size */
$size = filesize($inputFile);
if (!is_int($size)) {
throw new SodiumException('Could not obtain the file size');
}
/** @var resource $ifp */
$ifp = fopen($inputFile, 'rb');
if (!is_resource($ifp)) {
throw new SodiumException('Could not open input file for reading');
}
/** @var resource $ofp */
$ofp = fopen($outputFile, 'wb');
if (!is_resource($ofp)) {
fclose($ifp);
throw new SodiumException('Could not open output file for writing');
}
/** @var string $ephKeypair */
$ephKeypair = ParagonIE_Sodium_Compat::crypto_box_keypair();
/** @var string $msgKeypair */
$msgKeypair = ParagonIE_Sodium_Compat::crypto_box_keypair_from_secretkey_and_publickey(
ParagonIE_Sodium_Compat::crypto_box_secretkey($ephKeypair),
$publicKey
);
/** @var string $ephemeralPK */
$ephemeralPK = ParagonIE_Sodium_Compat::crypto_box_publickey($ephKeypair);
/** @var string $nonce */
$nonce = ParagonIE_Sodium_Compat::crypto_generichash(
$ephemeralPK . $publicKey,
'',
24
);
/** @var int $firstWrite */
$firstWrite = fwrite(
$ofp,
$ephemeralPK,
ParagonIE_Sodium_Compat::CRYPTO_BOX_PUBLICKEYBYTES
);
if (!is_int($firstWrite)) {
fclose($ifp);
fclose($ofp);
ParagonIE_Sodium_Compat::memzero($ephKeypair);
throw new SodiumException('Could not write to output file');
}
if ($firstWrite !== ParagonIE_Sodium_Compat::CRYPTO_BOX_PUBLICKEYBYTES) {
ParagonIE_Sodium_Compat::memzero($ephKeypair);
fclose($ifp);
fclose($ofp);
throw new SodiumException('Error writing public key to output file');
}
$res = self::box_encrypt($ifp, $ofp, $size, $nonce, $msgKeypair);
fclose($ifp);
fclose($ofp);
try {
ParagonIE_Sodium_Compat::memzero($nonce);
ParagonIE_Sodium_Compat::memzero($ephKeypair);
} catch (SodiumException $ex) {
/** @psalm-suppress PossiblyUndefinedVariable */
unset($ephKeypair);
}
return $res;
}
/**
* Open a sealed file (rather than a string). Uses less memory than
* ParagonIE_Sodium_Compat::crypto_box_seal_open(), but produces
* the same result.
*
* Warning: Does not protect against TOCTOU attacks. You should
* just load the file into memory and use crypto_box_seal_open() if
* you are worried about those.
*
* @param string $inputFile
* @param string $outputFile
* @param string $ecdhKeypair
* @return bool
* @throws SodiumException
* @throws TypeError
*/
public static function box_seal_open($inputFile, $outputFile, $ecdhKeypair)
{
/* Type checks: */
if (!is_string($inputFile)) {
throw new TypeError('Argument 1 must be a string, ' . gettype($inputFile) . ' given.');
}
if (!is_string($outputFile)) {
throw new TypeError('Argument 2 must be a string, ' . gettype($outputFile) . ' given.');
}
if (!is_string($ecdhKeypair)) {
throw new TypeError('Argument 3 must be a string, ' . gettype($ecdhKeypair) . ' given.');
}
/* Input validation: */
if (self::strlen($ecdhKeypair) !== ParagonIE_Sodium_Compat::CRYPTO_BOX_KEYPAIRBYTES) {
throw new TypeError('Argument 3 must be CRYPTO_BOX_KEYPAIRBYTES bytes');
}
$publicKey = ParagonIE_Sodium_Compat::crypto_box_publickey($ecdhKeypair);
/** @var int $size */
$size = filesize($inputFile);
if (!is_int($size)) {
throw new SodiumException('Could not obtain the file size');
}
/** @var resource $ifp */
$ifp = fopen($inputFile, 'rb');
if (!is_resource($ifp)) {
throw new SodiumException('Could not open input file for reading');
}
/** @var resource $ofp */
$ofp = fopen($outputFile, 'wb');
if (!is_resource($ofp)) {
fclose($ifp);
throw new SodiumException('Could not open output file for writing');
}
$ephemeralPK = fread($ifp, ParagonIE_Sodium_Compat::CRYPTO_BOX_PUBLICKEYBYTES);
if (!is_string($ephemeralPK)) {
throw new SodiumException('Could not read input file');
}
if (self::strlen($ephemeralPK) !== ParagonIE_Sodium_Compat::CRYPTO_BOX_PUBLICKEYBYTES) {
fclose($ifp);
fclose($ofp);
throw new SodiumException('Could not read public key from sealed file');
}
$nonce = ParagonIE_Sodium_Compat::crypto_generichash(
$ephemeralPK . $publicKey,
'',
24
);
$msgKeypair = ParagonIE_Sodium_Compat::crypto_box_keypair_from_secretkey_and_publickey(
ParagonIE_Sodium_Compat::crypto_box_secretkey($ecdhKeypair),
$ephemeralPK
);
$res = self::box_decrypt($ifp, $ofp, $size, $nonce, $msgKeypair);
fclose($ifp);
fclose($ofp);
try {
ParagonIE_Sodium_Compat::memzero($nonce);
ParagonIE_Sodium_Compat::memzero($ephKeypair);
} catch (SodiumException $ex) {
if (isset($ephKeypair)) {
unset($ephKeypair);
}
}
return $res;
}
/**
* Calculate the BLAKE2b hash of a file.
*
* @param string $filePath Absolute path to a file on the filesystem
* @param string|null $key BLAKE2b key
* @param int $outputLength Length of hash output
*
* @return string BLAKE2b hash
* @throws SodiumException
* @throws TypeError
* @psalm-suppress FailedTypeResolution
*/
public static function generichash($filePath, $key = '', $outputLength = 32)
{
/* Type checks: */
if (!is_string($filePath)) {
throw new TypeError('Argument 1 must be a string, ' . gettype($filePath) . ' given.');
}
if (!is_string($key)) {
if (is_null($key)) {
$key = '';
} else {
throw new TypeError('Argument 2 must be a string, ' . gettype($key) . ' given.');
}
}
if (!is_int($outputLength)) {
if (!is_numeric($outputLength)) {
throw new TypeError('Argument 3 must be an integer, ' . gettype($outputLength) . ' given.');
}
$outputLength = (int) $outputLength;
}
/* Input validation: */
if (!empty($key)) {
if (self::strlen($key) < ParagonIE_Sodium_Compat::CRYPTO_GENERICHASH_KEYBYTES_MIN) {
throw new TypeError('Argument 2 must be at least CRYPTO_GENERICHASH_KEYBYTES_MIN bytes');
}
if (self::strlen($key) > ParagonIE_Sodium_Compat::CRYPTO_GENERICHASH_KEYBYTES_MAX) {
throw new TypeError('Argument 2 must be at most CRYPTO_GENERICHASH_KEYBYTES_MAX bytes');
}
}
if ($outputLength < ParagonIE_Sodium_Compat::CRYPTO_GENERICHASH_BYTES_MIN) {
throw new SodiumException('Argument 3 must be at least CRYPTO_GENERICHASH_BYTES_MIN');
}
if ($outputLength > ParagonIE_Sodium_Compat::CRYPTO_GENERICHASH_BYTES_MAX) {
throw new SodiumException('Argument 3 must be at least CRYPTO_GENERICHASH_BYTES_MAX');
}
/** @var int $size */
$size = filesize($filePath);
if (!is_int($size)) {
throw new SodiumException('Could not obtain the file size');
}
/** @var resource $fp */
$fp = fopen($filePath, 'rb');
if (!is_resource($fp)) {
throw new SodiumException('Could not open input file for reading');
}
$ctx = ParagonIE_Sodium_Compat::crypto_generichash_init($key, $outputLength);
while ($size > 0) {
$blockSize = $size > 64
? 64
: $size;
$read = fread($fp, $blockSize);
if (!is_string($read)) {
throw new SodiumException('Could not read input file');
}
ParagonIE_Sodium_Compat::crypto_generichash_update($ctx, $read);
$size -= $blockSize;
}
fclose($fp);
return ParagonIE_Sodium_Compat::crypto_generichash_final($ctx, $outputLength);
}
/**
* Encrypt a file (rather than a string). Uses less memory than
* ParagonIE_Sodium_Compat::crypto_secretbox(), but produces
* the same result.
*
* @param string $inputFile Absolute path to a file on the filesystem
* @param string $outputFile Absolute path to a file on the filesystem
* @param string $nonce Number to be used only once
* @param string $key Encryption key
*
* @return bool
* @throws SodiumException
* @throws TypeError
*/
public static function secretbox($inputFile, $outputFile, $nonce, $key)
{
/* Type checks: */
if (!is_string($inputFile)) {
throw new TypeError('Argument 1 must be a string, ' . gettype($inputFile) . ' given..');
}
if (!is_string($outputFile)) {
throw new TypeError('Argument 2 must be a string, ' . gettype($outputFile) . ' given.');
}
if (!is_string($nonce)) {
throw new TypeError('Argument 3 must be a string, ' . gettype($nonce) . ' given.');
}
/* Input validation: */
if (self::strlen($nonce) !== ParagonIE_Sodium_Compat::CRYPTO_SECRETBOX_NONCEBYTES) {
throw new TypeError('Argument 3 must be CRYPTO_SECRETBOX_NONCEBYTES bytes');
}
if (!is_string($key)) {
throw new TypeError('Argument 4 must be a string, ' . gettype($key) . ' given.');
}
if (self::strlen($key) !== ParagonIE_Sodium_Compat::CRYPTO_SECRETBOX_KEYBYTES) {
throw new TypeError('Argument 4 must be CRYPTO_SECRETBOX_KEYBYTES bytes');
}
/** @var int $size */
$size = filesize($inputFile);
if (!is_int($size)) {
throw new SodiumException('Could not obtain the file size');
}
/** @var resource $ifp */
$ifp = fopen($inputFile, 'rb');
if (!is_resource($ifp)) {
throw new SodiumException('Could not open input file for reading');
}
/** @var resource $ofp */
$ofp = fopen($outputFile, 'wb');
if (!is_resource($ofp)) {
fclose($ifp);
throw new SodiumException('Could not open output file for writing');
}
$res = self::secretbox_encrypt($ifp, $ofp, $size, $nonce, $key);
fclose($ifp);
fclose($ofp);
return $res;
}
/**
* Seal a file (rather than a string). Uses less memory than
* ParagonIE_Sodium_Compat::crypto_secretbox_open(), but produces
* the same result.
*
* Warning: Does not protect against TOCTOU attacks. You should
* just load the file into memory and use crypto_secretbox_open() if
* you are worried about those.
*
* @param string $inputFile
* @param string $outputFile
* @param string $nonce
* @param string $key
* @return bool
* @throws SodiumException
* @throws TypeError
*/
public static function secretbox_open($inputFile, $outputFile, $nonce, $key)
{
/* Type checks: */
if (!is_string($inputFile)) {
throw new TypeError('Argument 1 must be a string, ' . gettype($inputFile) . ' given.');
}
if (!is_string($outputFile)) {
throw new TypeError('Argument 2 must be a string, ' . gettype($outputFile) . ' given.');
}
if (!is_string($nonce)) {
throw new TypeError('Argument 3 must be a string, ' . gettype($nonce) . ' given.');
}
if (!is_string($key)) {
throw new TypeError('Argument 4 must be a string, ' . gettype($key) . ' given.');
}
/* Input validation: */
if (self::strlen($nonce) !== ParagonIE_Sodium_Compat::CRYPTO_SECRETBOX_NONCEBYTES) {
throw new TypeError('Argument 4 must be CRYPTO_SECRETBOX_NONCEBYTES bytes');
}
if (self::strlen($key) !== ParagonIE_Sodium_Compat::CRYPTO_SECRETBOX_KEYBYTES) {
throw new TypeError('Argument 4 must be CRYPTO_SECRETBOXBOX_KEYBYTES bytes');
}
/** @var int $size */
$size = filesize($inputFile);
if (!is_int($size)) {
throw new SodiumException('Could not obtain the file size');
}
/** @var resource $ifp */
$ifp = fopen($inputFile, 'rb');
if (!is_resource($ifp)) {
throw new SodiumException('Could not open input file for reading');
}
/** @var resource $ofp */
$ofp = fopen($outputFile, 'wb');
if (!is_resource($ofp)) {
fclose($ifp);
throw new SodiumException('Could not open output file for writing');
}
$res = self::secretbox_decrypt($ifp, $ofp, $size, $nonce, $key);
fclose($ifp);
fclose($ofp);
try {
ParagonIE_Sodium_Compat::memzero($key);
} catch (SodiumException $ex) {
/** @psalm-suppress PossiblyUndefinedVariable */
unset($key);
}
return $res;
}
/**
* Sign a file (rather than a string). Uses less memory than
* ParagonIE_Sodium_Compat::crypto_sign_detached(), but produces
* the same result.
*
* @param string $filePath Absolute path to a file on the filesystem
* @param string $secretKey Secret signing key
*
* @return string Ed25519 signature
* @throws SodiumException
* @throws TypeError
*/
public static function sign($filePath, $secretKey)
{
/* Type checks: */
if (!is_string($filePath)) {
throw new TypeError('Argument 1 must be a string, ' . gettype($filePath) . ' given.');
}
if (!is_string($secretKey)) {
throw new TypeError('Argument 2 must be a string, ' . gettype($secretKey) . ' given.');
}
/* Input validation: */
if (self::strlen($secretKey) !== ParagonIE_Sodium_Compat::CRYPTO_SIGN_SECRETKEYBYTES) {
throw new TypeError('Argument 2 must be CRYPTO_SIGN_SECRETKEYBYTES bytes');
}
if (PHP_INT_SIZE === 4) {
return self::sign_core32($filePath, $secretKey);
}
/** @var int $size */
$size = filesize($filePath);
if (!is_int($size)) {
throw new SodiumException('Could not obtain the file size');
}
/** @var resource $fp */
$fp = fopen($filePath, 'rb');
if (!is_resource($fp)) {
throw new SodiumException('Could not open input file for reading');
}
/** @var string $az */
$az = hash('sha512', self::substr($secretKey, 0, 32), true);
$az[0] = self::intToChr(self::chrToInt($az[0]) & 248);
$az[31] = self::intToChr((self::chrToInt($az[31]) & 63) | 64);
$hs = hash_init('sha512');
self::hash_update($hs, self::substr($az, 32, 32));
/** @var resource $hs */
$hs = self::updateHashWithFile($hs, $fp, $size);
/** @var string $nonceHash */
$nonceHash = hash_final($hs, true);
/** @var string $pk */
$pk = self::substr($secretKey, 32, 32);
/** @var string $nonce */
$nonce = ParagonIE_Sodium_Core_Ed25519::sc_reduce($nonceHash) . self::substr($nonceHash, 32);
/** @var string $sig */
$sig = ParagonIE_Sodium_Core_Ed25519::ge_p3_tobytes(
ParagonIE_Sodium_Core_Ed25519::ge_scalarmult_base($nonce)
);
$hs = hash_init('sha512');
self::hash_update($hs, self::substr($sig, 0, 32));
self::hash_update($hs, self::substr($pk, 0, 32));
/** @var resource $hs */
$hs = self::updateHashWithFile($hs, $fp, $size);
/** @var string $hramHash */
$hramHash = hash_final($hs, true);
/** @var string $hram */
$hram = ParagonIE_Sodium_Core_Ed25519::sc_reduce($hramHash);
/** @var string $sigAfter */
$sigAfter = ParagonIE_Sodium_Core_Ed25519::sc_muladd($hram, $az, $nonce);
/** @var string $sig */
$sig = self::substr($sig, 0, 32) . self::substr($sigAfter, 0, 32);
try {
ParagonIE_Sodium_Compat::memzero($az);
} catch (SodiumException $ex) {
$az = null;
}
fclose($fp);
return $sig;
}
/**
* Verify a file (rather than a string). Uses less memory than
* ParagonIE_Sodium_Compat::crypto_sign_verify_detached(), but
* produces the same result.
*
* @param string $sig Ed25519 signature
* @param string $filePath Absolute path to a file on the filesystem
* @param string $publicKey Signing public key
*
* @return bool
* @throws SodiumException
* @throws TypeError
* @throws Exception
*/
public static function verify($sig, $filePath, $publicKey)
{
/* Type checks: */
if (!is_string($sig)) {
throw new TypeError('Argument 1 must be a string, ' . gettype($sig) . ' given.');
}
if (!is_string($filePath)) {
throw new TypeError('Argument 2 must be a string, ' . gettype($filePath) . ' given.');
}
if (!is_string($publicKey)) {
throw new TypeError('Argument 3 must be a string, ' . gettype($publicKey) . ' given.');
}
/* Input validation: */
if (self::strlen($sig) !== ParagonIE_Sodium_Compat::CRYPTO_SIGN_BYTES) {
throw new TypeError('Argument 1 must be CRYPTO_SIGN_BYTES bytes');
}
if (self::strlen($publicKey) !== ParagonIE_Sodium_Compat::CRYPTO_SIGN_PUBLICKEYBYTES) {
throw new TypeError('Argument 3 must be CRYPTO_SIGN_PUBLICKEYBYTES bytes');
}
if (self::strlen($sig) < 64) {
throw new SodiumException('Signature is too short');
}
if (PHP_INT_SIZE === 4) {
return self::verify_core32($sig, $filePath, $publicKey);
}
/* Security checks */
if (
(ParagonIE_Sodium_Core_Ed25519::chrToInt($sig[63]) & 240)
&&
ParagonIE_Sodium_Core_Ed25519::check_S_lt_L(self::substr($sig, 32, 32))
) {
throw new SodiumException('S < L - Invalid signature');
}
if (ParagonIE_Sodium_Core_Ed25519::small_order($sig)) {
throw new SodiumException('Signature is on too small of an order');
}
if ((self::chrToInt($sig[63]) & 224) !== 0) {
throw new SodiumException('Invalid signature');
}
$d = 0;
for ($i = 0; $i < 32; ++$i) {
$d |= self::chrToInt($publicKey[$i]);
}
if ($d === 0) {
throw new SodiumException('All zero public key');
}
/** @var int $size */
$size = filesize($filePath);
if (!is_int($size)) {
throw new SodiumException('Could not obtain the file size');
}
/** @var resource $fp */
$fp = fopen($filePath, 'rb');
if (!is_resource($fp)) {
throw new SodiumException('Could not open input file for reading');
}
/** @var bool The original value of ParagonIE_Sodium_Compat::$fastMult */
$orig = ParagonIE_Sodium_Compat::$fastMult;
// Set ParagonIE_Sodium_Compat::$fastMult to true to speed up verification.
ParagonIE_Sodium_Compat::$fastMult = true;
/** @var ParagonIE_Sodium_Core_Curve25519_Ge_P3 $A */
$A = ParagonIE_Sodium_Core_Ed25519::ge_frombytes_negate_vartime($publicKey);
$hs = hash_init('sha512');
self::hash_update($hs, self::substr($sig, 0, 32));
self::hash_update($hs, self::substr($publicKey, 0, 32));
/** @var resource $hs */
$hs = self::updateHashWithFile($hs, $fp, $size);
/** @var string $hDigest */
$hDigest = hash_final($hs, true);
/** @var string $h */
$h = ParagonIE_Sodium_Core_Ed25519::sc_reduce($hDigest) . self::substr($hDigest, 32);
/** @var ParagonIE_Sodium_Core_Curve25519_Ge_P2 $R */
$R = ParagonIE_Sodium_Core_Ed25519::ge_double_scalarmult_vartime(
$h,
$A,
self::substr($sig, 32)
);
/** @var string $rcheck */
$rcheck = ParagonIE_Sodium_Core_Ed25519::ge_tobytes($R);
// Close the file handle
fclose($fp);
// Reset ParagonIE_Sodium_Compat::$fastMult to what it was before.
ParagonIE_Sodium_Compat::$fastMult = $orig;
return self::verify_32($rcheck, self::substr($sig, 0, 32));
}
/**
* @param resource $ifp
* @param resource $ofp
* @param int $mlen
* @param string $nonce
* @param string $boxKeypair
* @return bool
* @throws SodiumException
* @throws TypeError
*/
protected static function box_encrypt($ifp, $ofp, $mlen, $nonce, $boxKeypair)
{
if (PHP_INT_SIZE === 4) {
return self::secretbox_encrypt(
$ifp,
$ofp,
$mlen,
$nonce,
ParagonIE_Sodium_Crypto32::box_beforenm(
ParagonIE_Sodium_Crypto32::box_secretkey($boxKeypair),
ParagonIE_Sodium_Crypto32::box_publickey($boxKeypair)
)
);
}
return self::secretbox_encrypt(
$ifp,
$ofp,
$mlen,
$nonce,
ParagonIE_Sodium_Crypto::box_beforenm(
ParagonIE_Sodium_Crypto::box_secretkey($boxKeypair),
ParagonIE_Sodium_Crypto::box_publickey($boxKeypair)
)
);
}
/**
* @param resource $ifp
* @param resource $ofp
* @param int $mlen
* @param string $nonce
* @param string $boxKeypair
* @return bool
* @throws SodiumException
* @throws TypeError
*/
protected static function box_decrypt($ifp, $ofp, $mlen, $nonce, $boxKeypair)
{
if (PHP_INT_SIZE === 4) {
return self::secretbox_decrypt(
$ifp,
$ofp,
$mlen,
$nonce,
ParagonIE_Sodium_Crypto32::box_beforenm(
ParagonIE_Sodium_Crypto32::box_secretkey($boxKeypair),
ParagonIE_Sodium_Crypto32::box_publickey($boxKeypair)
)
);
}
return self::secretbox_decrypt(
$ifp,
$ofp,
$mlen,
$nonce,
ParagonIE_Sodium_Crypto::box_beforenm(
ParagonIE_Sodium_Crypto::box_secretkey($boxKeypair),
ParagonIE_Sodium_Crypto::box_publickey($boxKeypair)
)
);
}
/**
* Encrypt a file
*
* @param resource $ifp
* @param resource $ofp
* @param int $mlen
* @param string $nonce
* @param string $key
* @return bool
* @throws SodiumException
* @throws TypeError
*/
protected static function secretbox_encrypt($ifp, $ofp, $mlen, $nonce, $key)
{
if (PHP_INT_SIZE === 4) {
return self::secretbox_encrypt_core32($ifp, $ofp, $mlen, $nonce, $key);
}
$plaintext = fread($ifp, 32);
if (!is_string($plaintext)) {
throw new SodiumException('Could not read input file');
}
$first32 = self::ftell($ifp);
/** @var string $subkey */
$subkey = ParagonIE_Sodium_Core_HSalsa20::hsalsa20($nonce, $key);
/** @var string $realNonce */
$realNonce = ParagonIE_Sodium_Core_Util::substr($nonce, 16, 8);
/** @var string $block0 */
$block0 = str_repeat("\x00", 32);
/** @var int $mlen - Length of the plaintext message */
$mlen0 = $mlen;
if ($mlen0 > 64 - ParagonIE_Sodium_Crypto::secretbox_xsalsa20poly1305_ZEROBYTES) {
$mlen0 = 64 - ParagonIE_Sodium_Crypto::secretbox_xsalsa20poly1305_ZEROBYTES;
}
$block0 .= ParagonIE_Sodium_Core_Util::substr($plaintext, 0, $mlen0);
/** @var string $block0 */
$block0 = ParagonIE_Sodium_Core_Salsa20::salsa20_xor(
$block0,
$realNonce,
$subkey
);
$state = new ParagonIE_Sodium_Core_Poly1305_State(
ParagonIE_Sodium_Core_Util::substr(
$block0,
0,
ParagonIE_Sodium_Crypto::onetimeauth_poly1305_KEYBYTES
)
);
// Pre-write 16 blank bytes for the Poly1305 tag
$start = self::ftell($ofp);
fwrite($ofp, str_repeat("\x00", 16));
/** @var string $c */
$cBlock = ParagonIE_Sodium_Core_Util::substr(
$block0,
ParagonIE_Sodium_Crypto::secretbox_xsalsa20poly1305_ZEROBYTES
);
$state->update($cBlock);
fwrite($ofp, $cBlock);
$mlen -= 32;
/** @var int $iter */
$iter = 1;
/** @var int $incr */
$incr = self::BUFFER_SIZE >> 6;
/*
* Set the cursor to the end of the first half-block. All future bytes will
* generated from salsa20_xor_ic, starting from 1 (second block).
*/
fseek($ifp, $first32, SEEK_SET);
while ($mlen > 0) {
$blockSize = $mlen > self::BUFFER_SIZE
? self::BUFFER_SIZE
: $mlen;
$plaintext = fread($ifp, $blockSize);
if (!is_string($plaintext)) {
throw new SodiumException('Could not read input file');
}
$cBlock = ParagonIE_Sodium_Core_Salsa20::salsa20_xor_ic(
$plaintext,
$realNonce,
$iter,
$subkey
);
fwrite($ofp, $cBlock, $blockSize);
$state->update($cBlock);
$mlen -= $blockSize;
$iter += $incr;
}
try {
ParagonIE_Sodium_Compat::memzero($block0);
ParagonIE_Sodium_Compat::memzero($subkey);
} catch (SodiumException $ex) {
$block0 = null;
$subkey = null;
}
$end = self::ftell($ofp);
/*
* Write the Poly1305 authentication tag that provides integrity
* over the ciphertext (encrypt-then-MAC)
*/
fseek($ofp, $start, SEEK_SET);
fwrite($ofp, $state->finish(), ParagonIE_Sodium_Compat::CRYPTO_SECRETBOX_MACBYTES);
fseek($ofp, $end, SEEK_SET);
unset($state);
return true;
}
/**
* Decrypt a file
*
* @param resource $ifp
* @param resource $ofp
* @param int $mlen
* @param string $nonce
* @param string $key
* @return bool
* @throws SodiumException
* @throws TypeError
*/
protected static function secretbox_decrypt($ifp, $ofp, $mlen, $nonce, $key)
{
if (PHP_INT_SIZE === 4) {
return self::secretbox_decrypt_core32($ifp, $ofp, $mlen, $nonce, $key);
}
$tag = fread($ifp, 16);
if (!is_string($tag)) {
throw new SodiumException('Could not read input file');
}
/** @var string $subkey */
$subkey = ParagonIE_Sodium_Core_HSalsa20::hsalsa20($nonce, $key);
/** @var string $realNonce */
$realNonce = ParagonIE_Sodium_Core_Util::substr($nonce, 16, 8);
/** @var string $block0 */
$block0 = ParagonIE_Sodium_Core_Salsa20::salsa20(
64,
ParagonIE_Sodium_Core_Util::substr($nonce, 16, 8),
$subkey
);
/* Verify the Poly1305 MAC -before- attempting to decrypt! */
$state = new ParagonIE_Sodium_Core_Poly1305_State(self::substr($block0, 0, 32));
if (!self::onetimeauth_verify($state, $ifp, $tag, $mlen)) {
throw new SodiumException('Invalid MAC');
}
/*
* Set the cursor to the end of the first half-block. All future bytes will
* generated from salsa20_xor_ic, starting from 1 (second block).
*/
$first32 = fread($ifp, 32);
if (!is_string($first32)) {
throw new SodiumException('Could not read input file');
}
$first32len = self::strlen($first32);
fwrite(
$ofp,
self::xorStrings(
self::substr($block0, 32, $first32len),
self::substr($first32, 0, $first32len)
)
);
$mlen -= 32;
/** @var int $iter */
$iter = 1;
/** @var int $incr */
$incr = self::BUFFER_SIZE >> 6;
/* Decrypts ciphertext, writes to output file. */
while ($mlen > 0) {
$blockSize = $mlen > self::BUFFER_SIZE
? self::BUFFER_SIZE
: $mlen;
$ciphertext = fread($ifp, $blockSize);
if (!is_string($ciphertext)) {
throw new SodiumException('Could not read input file');
}
$pBlock = ParagonIE_Sodium_Core_Salsa20::salsa20_xor_ic(
$ciphertext,
$realNonce,
$iter,
$subkey
);
fwrite($ofp, $pBlock, $blockSize);
$mlen -= $blockSize;
$iter += $incr;
}
return true;
}
/**
* @param ParagonIE_Sodium_Core_Poly1305_State $state
* @param resource $ifp
* @param string $tag
* @param int $mlen
* @return bool
* @throws SodiumException
* @throws TypeError
*/
protected static function onetimeauth_verify(
ParagonIE_Sodium_Core_Poly1305_State $state,
$ifp,
$tag = '',
$mlen = 0
) {
/** @var int $pos */
$pos = self::ftell($ifp);
/** @var int $iter */
$iter = 1;
/** @var int $incr */
$incr = self::BUFFER_SIZE >> 6;
while ($mlen > 0) {
$blockSize = $mlen > self::BUFFER_SIZE
? self::BUFFER_SIZE
: $mlen;
$ciphertext = fread($ifp, $blockSize);
if (!is_string($ciphertext)) {
throw new SodiumException('Could not read input file');
}
$state->update($ciphertext);
$mlen -= $blockSize;
$iter += $incr;
}
$res = ParagonIE_Sodium_Core_Util::verify_16($tag, $state->finish());
fseek($ifp, $pos, SEEK_SET);
return $res;
}
/**
* Update a hash context with the contents of a file, without
* loading the entire file into memory.
*
* @param resource|HashContext $hash
* @param resource $fp
* @param int $size
* @return resource|object Resource on PHP < 7.2, HashContext object on PHP >= 7.2
* @throws SodiumException
* @throws TypeError
* @psalm-suppress PossiblyInvalidArgument
* PHP 7.2 changes from a resource to an object,
* which causes Psalm to complain about an error.
* @psalm-suppress TypeCoercion
* Ditto.
*/
public static function updateHashWithFile($hash, $fp, $size = 0)
{
/* Type checks: */
if (PHP_VERSION_ID < 70200) {
if (!is_resource($hash)) {
throw new TypeError('Argument 1 must be a resource, ' . gettype($hash) . ' given.');
}
} else {
if (!is_object($hash)) {
throw new TypeError('Argument 1 must be an object (PHP 7.2+), ' . gettype($hash) . ' given.');
}
}
if (!is_resource($fp)) {
throw new TypeError('Argument 2 must be a resource, ' . gettype($fp) . ' given.');
}
if (!is_int($size)) {
throw new TypeError('Argument 3 must be an integer, ' . gettype($size) . ' given.');
}
/** @var int $originalPosition */
$originalPosition = self::ftell($fp);
// Move file pointer to beginning of file
fseek($fp, 0, SEEK_SET);
for ($i = 0; $i < $size; $i += self::BUFFER_SIZE) {
/** @var string|bool $message */
$message = fread(
$fp,
($size - $i) > self::BUFFER_SIZE
? $size - $i
: self::BUFFER_SIZE
);
if (!is_string($message)) {
throw new SodiumException('Unexpected error reading from file.');
}
/** @var string $message */
/** @psalm-suppress InvalidArgument */
self::hash_update($hash, $message);
}
// Reset file pointer's position
fseek($fp, $originalPosition, SEEK_SET);
return $hash;
}
/**
* Sign a file (rather than a string). Uses less memory than
* ParagonIE_Sodium_Compat::crypto_sign_detached(), but produces
* the same result. (32-bit)
*
* @param string $filePath Absolute path to a file on the filesystem
* @param string $secretKey Secret signing key
*
* @return string Ed25519 signature
* @throws SodiumException
* @throws TypeError
*/
private static function sign_core32($filePath, $secretKey)
{
$size = filesize($filePath);
if (!is_int($size)) {
throw new SodiumException('Could not obtain the file size');
}
$fp = fopen($filePath, 'rb');
if (!is_resource($fp)) {
throw new SodiumException('Could not open input file for reading');
}
/** @var string $az */
$az = hash('sha512', self::substr($secretKey, 0, 32), true);
$az[0] = self::intToChr(self::chrToInt($az[0]) & 248);
$az[31] = self::intToChr((self::chrToInt($az[31]) & 63) | 64);
$hs = hash_init('sha512');
self::hash_update($hs, self::substr($az, 32, 32));
/** @var resource $hs */
$hs = self::updateHashWithFile($hs, $fp, $size);
$nonceHash = hash_final($hs, true);
$pk = self::substr($secretKey, 32, 32);
$nonce = ParagonIE_Sodium_Core32_Ed25519::sc_reduce($nonceHash) . self::substr($nonceHash, 32);
$sig = ParagonIE_Sodium_Core32_Ed25519::ge_p3_tobytes(
ParagonIE_Sodium_Core32_Ed25519::ge_scalarmult_base($nonce)
);
$hs = hash_init('sha512');
self::hash_update($hs, self::substr($sig, 0, 32));
self::hash_update($hs, self::substr($pk, 0, 32));
/** @var resource $hs */
$hs = self::updateHashWithFile($hs, $fp, $size);
$hramHash = hash_final($hs, true);
$hram = ParagonIE_Sodium_Core32_Ed25519::sc_reduce($hramHash);
$sigAfter = ParagonIE_Sodium_Core32_Ed25519::sc_muladd($hram, $az, $nonce);
/** @var string $sig */
$sig = self::substr($sig, 0, 32) . self::substr($sigAfter, 0, 32);
try {
ParagonIE_Sodium_Compat::memzero($az);
} catch (SodiumException $ex) {
$az = null;
}
fclose($fp);
return $sig;
}
/**
*
* Verify a file (rather than a string). Uses less memory than
* ParagonIE_Sodium_Compat::crypto_sign_verify_detached(), but
* produces the same result. (32-bit)
*
* @param string $sig Ed25519 signature
* @param string $filePath Absolute path to a file on the filesystem
* @param string $publicKey Signing public key
*
* @return bool
* @throws SodiumException
* @throws Exception
*/
public static function verify_core32($sig, $filePath, $publicKey)
{
/* Security checks */
if (ParagonIE_Sodium_Core32_Ed25519::check_S_lt_L(self::substr($sig, 32, 32))) {
throw new SodiumException('S < L - Invalid signature');
}
if (ParagonIE_Sodium_Core32_Ed25519::small_order($sig)) {
throw new SodiumException('Signature is on too small of an order');
}
if ((self::chrToInt($sig[63]) & 224) !== 0) {
throw new SodiumException('Invalid signature');
}
$d = 0;
for ($i = 0; $i < 32; ++$i) {
$d |= self::chrToInt($publicKey[$i]);
}
if ($d === 0) {
throw new SodiumException('All zero public key');
}
/** @var int|bool $size */
$size = filesize($filePath);
if (!is_int($size)) {
throw new SodiumException('Could not obtain the file size');
}
/** @var int $size */
/** @var resource|bool $fp */
$fp = fopen($filePath, 'rb');
if (!is_resource($fp)) {
throw new SodiumException('Could not open input file for reading');
}
/** @var resource $fp */
/** @var bool The original value of ParagonIE_Sodium_Compat::$fastMult */
$orig = ParagonIE_Sodium_Compat::$fastMult;
// Set ParagonIE_Sodium_Compat::$fastMult to true to speed up verification.
ParagonIE_Sodium_Compat::$fastMult = true;
/** @var ParagonIE_Sodium_Core32_Curve25519_Ge_P3 $A */
$A = ParagonIE_Sodium_Core32_Ed25519::ge_frombytes_negate_vartime($publicKey);
$hs = hash_init('sha512');
self::hash_update($hs, self::substr($sig, 0, 32));
self::hash_update($hs, self::substr($publicKey, 0, 32));
/** @var resource $hs */
$hs = self::updateHashWithFile($hs, $fp, $size);
/** @var string $hDigest */
$hDigest = hash_final($hs, true);
/** @var string $h */
$h = ParagonIE_Sodium_Core32_Ed25519::sc_reduce($hDigest) . self::substr($hDigest, 32);
/** @var ParagonIE_Sodium_Core32_Curve25519_Ge_P2 $R */
$R = ParagonIE_Sodium_Core32_Ed25519::ge_double_scalarmult_vartime(
$h,
$A,
self::substr($sig, 32)
);
/** @var string $rcheck */
$rcheck = ParagonIE_Sodium_Core32_Ed25519::ge_tobytes($R);
// Close the file handle
fclose($fp);
// Reset ParagonIE_Sodium_Compat::$fastMult to what it was before.
ParagonIE_Sodium_Compat::$fastMult = $orig;
return self::verify_32($rcheck, self::substr($sig, 0, 32));
}
/**
* Encrypt a file (32-bit)
*
* @param resource $ifp
* @param resource $ofp
* @param int $mlen
* @param string $nonce
* @param string $key
* @return bool
* @throws SodiumException
* @throws TypeError
*/
protected static function secretbox_encrypt_core32($ifp, $ofp, $mlen, $nonce, $key)
{
$plaintext = fread($ifp, 32);
if (!is_string($plaintext)) {
throw new SodiumException('Could not read input file');
}
$first32 = self::ftell($ifp);
/** @var string $subkey */
$subkey = ParagonIE_Sodium_Core32_HSalsa20::hsalsa20($nonce, $key);
/** @var string $realNonce */
$realNonce = ParagonIE_Sodium_Core32_Util::substr($nonce, 16, 8);
/** @var string $block0 */
$block0 = str_repeat("\x00", 32);
/** @var int $mlen - Length of the plaintext message */
$mlen0 = $mlen;
if ($mlen0 > 64 - ParagonIE_Sodium_Crypto::secretbox_xsalsa20poly1305_ZEROBYTES) {
$mlen0 = 64 - ParagonIE_Sodium_Crypto::secretbox_xsalsa20poly1305_ZEROBYTES;
}
$block0 .= ParagonIE_Sodium_Core32_Util::substr($plaintext, 0, $mlen0);
/** @var string $block0 */
$block0 = ParagonIE_Sodium_Core32_Salsa20::salsa20_xor(
$block0,
$realNonce,
$subkey
);
$state = new ParagonIE_Sodium_Core32_Poly1305_State(
ParagonIE_Sodium_Core32_Util::substr(
$block0,
0,
ParagonIE_Sodium_Crypto::onetimeauth_poly1305_KEYBYTES
)
);
// Pre-write 16 blank bytes for the Poly1305 tag
$start = self::ftell($ofp);
fwrite($ofp, str_repeat("\x00", 16));
/** @var string $c */
$cBlock = ParagonIE_Sodium_Core32_Util::substr(
$block0,
ParagonIE_Sodium_Crypto::secretbox_xsalsa20poly1305_ZEROBYTES
);
$state->update($cBlock);
fwrite($ofp, $cBlock);
$mlen -= 32;
/** @var int $iter */
$iter = 1;
/** @var int $incr */
$incr = self::BUFFER_SIZE >> 6;
/*
* Set the cursor to the end of the first half-block. All future bytes will
* generated from salsa20_xor_ic, starting from 1 (second block).
*/
fseek($ifp, $first32, SEEK_SET);
while ($mlen > 0) {
$blockSize = $mlen > self::BUFFER_SIZE
? self::BUFFER_SIZE
: $mlen;
$plaintext = fread($ifp, $blockSize);
if (!is_string($plaintext)) {
throw new SodiumException('Could not read input file');
}
$cBlock = ParagonIE_Sodium_Core32_Salsa20::salsa20_xor_ic(
$plaintext,
$realNonce,
$iter,
$subkey
);
fwrite($ofp, $cBlock, $blockSize);
$state->update($cBlock);
$mlen -= $blockSize;
$iter += $incr;
}
try {
ParagonIE_Sodium_Compat::memzero($block0);
ParagonIE_Sodium_Compat::memzero($subkey);
} catch (SodiumException $ex) {
$block0 = null;
$subkey = null;
}
$end = self::ftell($ofp);
/*
* Write the Poly1305 authentication tag that provides integrity
* over the ciphertext (encrypt-then-MAC)
*/
fseek($ofp, $start, SEEK_SET);
fwrite($ofp, $state->finish(), ParagonIE_Sodium_Compat::CRYPTO_SECRETBOX_MACBYTES);
fseek($ofp, $end, SEEK_SET);
unset($state);
return true;
}
/**
* Decrypt a file (32-bit)
*
* @param resource $ifp
* @param resource $ofp
* @param int $mlen
* @param string $nonce
* @param string $key
* @return bool
* @throws SodiumException
* @throws TypeError
*/
protected static function secretbox_decrypt_core32($ifp, $ofp, $mlen, $nonce, $key)
{
$tag = fread($ifp, 16);
if (!is_string($tag)) {
throw new SodiumException('Could not read input file');
}
/** @var string $subkey */
$subkey = ParagonIE_Sodium_Core32_HSalsa20::hsalsa20($nonce, $key);
/** @var string $realNonce */
$realNonce = ParagonIE_Sodium_Core32_Util::substr($nonce, 16, 8);
/** @var string $block0 */
$block0 = ParagonIE_Sodium_Core32_Salsa20::salsa20(
64,
ParagonIE_Sodium_Core32_Util::substr($nonce, 16, 8),
$subkey
);
/* Verify the Poly1305 MAC -before- attempting to decrypt! */
$state = new ParagonIE_Sodium_Core32_Poly1305_State(self::substr($block0, 0, 32));
if (!self::onetimeauth_verify_core32($state, $ifp, $tag, $mlen)) {
throw new SodiumException('Invalid MAC');
}
/*
* Set the cursor to the end of the first half-block. All future bytes will
* generated from salsa20_xor_ic, starting from 1 (second block).
*/
$first32 = fread($ifp, 32);
if (!is_string($first32)) {
throw new SodiumException('Could not read input file');
}
$first32len = self::strlen($first32);
fwrite(
$ofp,
self::xorStrings(
self::substr($block0, 32, $first32len),
self::substr($first32, 0, $first32len)
)
);
$mlen -= 32;
/** @var int $iter */
$iter = 1;
/** @var int $incr */
$incr = self::BUFFER_SIZE >> 6;
/* Decrypts ciphertext, writes to output file. */
while ($mlen > 0) {
$blockSize = $mlen > self::BUFFER_SIZE
? self::BUFFER_SIZE
: $mlen;
$ciphertext = fread($ifp, $blockSize);
if (!is_string($ciphertext)) {
throw new SodiumException('Could not read input file');
}
$pBlock = ParagonIE_Sodium_Core32_Salsa20::salsa20_xor_ic(
$ciphertext,
$realNonce,
$iter,
$subkey
);
fwrite($ofp, $pBlock, $blockSize);
$mlen -= $blockSize;
$iter += $incr;
}
return true;
}
/**
* One-time message authentication for 32-bit systems
*
* @param ParagonIE_Sodium_Core32_Poly1305_State $state
* @param resource $ifp
* @param string $tag
* @param int $mlen
* @return bool
* @throws SodiumException
* @throws TypeError
*/
protected static function onetimeauth_verify_core32(
ParagonIE_Sodium_Core32_Poly1305_State $state,
$ifp,
$tag = '',
$mlen = 0
) {
/** @var int $pos */
$pos = self::ftell($ifp);
while ($mlen > 0) {
$blockSize = $mlen > self::BUFFER_SIZE
? self::BUFFER_SIZE
: $mlen;
$ciphertext = fread($ifp, $blockSize);
if (!is_string($ciphertext)) {
throw new SodiumException('Could not read input file');
}
$state->update($ciphertext);
$mlen -= $blockSize;
}
$res = ParagonIE_Sodium_Core32_Util::verify_16($tag, $state->finish());
fseek($ifp, $pos, SEEK_SET);
return $res;
}
/**
* @param resource $resource
* @return int
* @throws SodiumException
*/
private static function ftell($resource)
{
$return = ftell($resource);
if (!is_int($return)) {
throw new SodiumException('ftell() returned false');
}
return (int) $return;
}
}
