779 lines
25 KiB
PHP
779 lines
25 KiB
PHP
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<?php
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namespace Defuse\Crypto;
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use Defuse\Crypto\Exception as Ex;
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final class File
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{
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/**
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* Encrypts the input file, saving the ciphertext to the output file.
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*
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* @param string $inputFilename
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* @param string $outputFilename
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* @param Key $key
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* @return void
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*
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* @throws Ex\EnvironmentIsBrokenException
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* @throws Ex\IOException
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*/
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public static function encryptFile($inputFilename, $outputFilename, Key $key)
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{
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self::encryptFileInternal(
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$inputFilename,
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$outputFilename,
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KeyOrPassword::createFromKey($key)
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);
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}
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/**
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* Encrypts a file with a password, using a slow key derivation function to
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* make password cracking more expensive.
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*
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* @param string $inputFilename
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* @param string $outputFilename
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* @param string $password
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* @return void
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*
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* @throws Ex\EnvironmentIsBrokenException
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* @throws Ex\IOException
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*/
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public static function encryptFileWithPassword($inputFilename, $outputFilename, $password)
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{
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self::encryptFileInternal(
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$inputFilename,
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$outputFilename,
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KeyOrPassword::createFromPassword($password)
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);
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}
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/**
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* Decrypts the input file, saving the plaintext to the output file.
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*
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* @param string $inputFilename
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* @param string $outputFilename
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* @param Key $key
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* @return void
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*
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* @throws Ex\EnvironmentIsBrokenException
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* @throws Ex\IOException
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* @throws Ex\WrongKeyOrModifiedCiphertextException
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*/
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public static function decryptFile($inputFilename, $outputFilename, Key $key)
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{
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self::decryptFileInternal(
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$inputFilename,
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$outputFilename,
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KeyOrPassword::createFromKey($key)
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);
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}
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/**
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* Decrypts a file with a password, using a slow key derivation function to
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* make password cracking more expensive.
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*
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* @param string $inputFilename
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* @param string $outputFilename
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* @param string $password
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* @return void
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*
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* @throws Ex\EnvironmentIsBrokenException
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* @throws Ex\IOException
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* @throws Ex\WrongKeyOrModifiedCiphertextException
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*/
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public static function decryptFileWithPassword($inputFilename, $outputFilename, $password)
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{
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self::decryptFileInternal(
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$inputFilename,
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$outputFilename,
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KeyOrPassword::createFromPassword($password)
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);
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}
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/**
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* Takes two resource handles and encrypts the contents of the first,
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* writing the ciphertext into the second.
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*
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* @param resource $inputHandle
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* @param resource $outputHandle
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* @param Key $key
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* @return void
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*
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* @throws Ex\EnvironmentIsBrokenException
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* @throws Ex\WrongKeyOrModifiedCiphertextException
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*/
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public static function encryptResource($inputHandle, $outputHandle, Key $key)
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{
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self::encryptResourceInternal(
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$inputHandle,
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$outputHandle,
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KeyOrPassword::createFromKey($key)
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);
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}
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/**
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* Encrypts the contents of one resource handle into another with a
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* password, using a slow key derivation function to make password cracking
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* more expensive.
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*
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* @param resource $inputHandle
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* @param resource $outputHandle
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* @param string $password
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* @return void
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*
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* @throws Ex\EnvironmentIsBrokenException
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* @throws Ex\IOException
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* @throws Ex\WrongKeyOrModifiedCiphertextException
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*/
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public static function encryptResourceWithPassword($inputHandle, $outputHandle, $password)
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{
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self::encryptResourceInternal(
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$inputHandle,
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$outputHandle,
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KeyOrPassword::createFromPassword($password)
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);
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}
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/**
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* Takes two resource handles and decrypts the contents of the first,
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* writing the plaintext into the second.
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*
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* @param resource $inputHandle
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* @param resource $outputHandle
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* @param Key $key
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* @return void
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*
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* @throws Ex\EnvironmentIsBrokenException
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* @throws Ex\IOException
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* @throws Ex\WrongKeyOrModifiedCiphertextException
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*/
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public static function decryptResource($inputHandle, $outputHandle, Key $key)
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{
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self::decryptResourceInternal(
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$inputHandle,
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$outputHandle,
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KeyOrPassword::createFromKey($key)
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);
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}
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/**
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* Decrypts the contents of one resource into another with a password, using
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* a slow key derivation function to make password cracking more expensive.
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*
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* @param resource $inputHandle
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* @param resource $outputHandle
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* @param string $password
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* @return void
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*
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* @throws Ex\EnvironmentIsBrokenException
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* @throws Ex\IOException
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* @throws Ex\WrongKeyOrModifiedCiphertextException
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*/
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public static function decryptResourceWithPassword($inputHandle, $outputHandle, $password)
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{
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self::decryptResourceInternal(
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$inputHandle,
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$outputHandle,
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KeyOrPassword::createFromPassword($password)
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);
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}
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/**
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* Encrypts a file with either a key or a password.
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*
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* @param string $inputFilename
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* @param string $outputFilename
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* @param KeyOrPassword $secret
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* @return void
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*
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* @throws Ex\CryptoException
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* @throws Ex\IOException
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*/
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private static function encryptFileInternal($inputFilename, $outputFilename, KeyOrPassword $secret)
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{
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if (file_exists($inputFilename) && file_exists($outputFilename) && realpath($inputFilename) === realpath($outputFilename)) {
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throw new Ex\IOException('Input and output filenames must be different.');
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}
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/* Open the input file. */
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$if = @\fopen($inputFilename, 'rb');
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if ($if === false) {
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throw new Ex\IOException(
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'Cannot open input file for encrypting: ' .
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self::getLastErrorMessage()
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);
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}
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if (\is_callable('\\stream_set_read_buffer')) {
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/* This call can fail, but the only consequence is performance. */
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\stream_set_read_buffer($if, 0);
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}
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/* Open the output file. */
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$of = @\fopen($outputFilename, 'wb');
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if ($of === false) {
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\fclose($if);
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throw new Ex\IOException(
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'Cannot open output file for encrypting: ' .
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self::getLastErrorMessage()
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);
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}
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if (\is_callable('\\stream_set_write_buffer')) {
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/* This call can fail, but the only consequence is performance. */
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\stream_set_write_buffer($of, 0);
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}
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/* Perform the encryption. */
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try {
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self::encryptResourceInternal($if, $of, $secret);
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} catch (Ex\CryptoException $ex) {
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\fclose($if);
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\fclose($of);
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throw $ex;
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}
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/* Close the input file. */
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if (\fclose($if) === false) {
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\fclose($of);
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throw new Ex\IOException(
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'Cannot close input file after encrypting'
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);
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}
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/* Close the output file. */
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if (\fclose($of) === false) {
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throw new Ex\IOException(
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'Cannot close output file after encrypting'
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);
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}
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}
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/**
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* Decrypts a file with either a key or a password.
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*
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* @param string $inputFilename
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* @param string $outputFilename
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* @param KeyOrPassword $secret
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* @return void
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*
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* @throws Ex\CryptoException
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* @throws Ex\IOException
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*/
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private static function decryptFileInternal($inputFilename, $outputFilename, KeyOrPassword $secret)
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{
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if (file_exists($inputFilename) && file_exists($outputFilename) && realpath($inputFilename) === realpath($outputFilename)) {
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throw new Ex\IOException('Input and output filenames must be different.');
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}
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/* Open the input file. */
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$if = @\fopen($inputFilename, 'rb');
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if ($if === false) {
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throw new Ex\IOException(
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'Cannot open input file for decrypting: ' .
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self::getLastErrorMessage()
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);
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}
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if (\is_callable('\\stream_set_read_buffer')) {
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/* This call can fail, but the only consequence is performance. */
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\stream_set_read_buffer($if, 0);
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}
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/* Open the output file. */
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$of = @\fopen($outputFilename, 'wb');
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if ($of === false) {
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\fclose($if);
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throw new Ex\IOException(
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'Cannot open output file for decrypting: ' .
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self::getLastErrorMessage()
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);
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}
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if (\is_callable('\\stream_set_write_buffer')) {
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/* This call can fail, but the only consequence is performance. */
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\stream_set_write_buffer($of, 0);
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}
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/* Perform the decryption. */
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try {
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self::decryptResourceInternal($if, $of, $secret);
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} catch (Ex\CryptoException $ex) {
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\fclose($if);
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\fclose($of);
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throw $ex;
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}
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/* Close the input file. */
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if (\fclose($if) === false) {
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\fclose($of);
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throw new Ex\IOException(
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'Cannot close input file after decrypting'
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);
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}
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/* Close the output file. */
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if (\fclose($of) === false) {
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throw new Ex\IOException(
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'Cannot close output file after decrypting'
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);
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}
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}
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/**
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* Encrypts a resource with either a key or a password.
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*
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* @param resource $inputHandle
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* @param resource $outputHandle
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* @param KeyOrPassword $secret
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* @return void
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*
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* @throws Ex\EnvironmentIsBrokenException
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* @throws Ex\IOException
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* @psalm-suppress PossiblyInvalidArgument
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* Fixes erroneous errors caused by PHP 7.2 switching the return value
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* of hash_init from a resource to a HashContext.
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*/
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private static function encryptResourceInternal($inputHandle, $outputHandle, KeyOrPassword $secret)
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{
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if (! \is_resource($inputHandle)) {
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throw new Ex\IOException(
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'Input handle must be a resource!'
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);
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}
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if (! \is_resource($outputHandle)) {
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throw new Ex\IOException(
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'Output handle must be a resource!'
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);
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}
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$inputStat = \fstat($inputHandle);
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$inputSize = $inputStat['size'];
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$file_salt = Core::secureRandom(Core::SALT_BYTE_SIZE);
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$keys = $secret->deriveKeys($file_salt);
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$ekey = $keys->getEncryptionKey();
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$akey = $keys->getAuthenticationKey();
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$ivsize = Core::BLOCK_BYTE_SIZE;
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$iv = Core::secureRandom($ivsize);
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/* Initialize a streaming HMAC state. */
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/** @var mixed $hmac */
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$hmac = \hash_init(Core::HASH_FUNCTION_NAME, HASH_HMAC, $akey);
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Core::ensureTrue(
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\is_resource($hmac) || \is_object($hmac),
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'Cannot initialize a hash context'
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);
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/* Write the header, salt, and IV. */
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self::writeBytes(
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$outputHandle,
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Core::CURRENT_VERSION . $file_salt . $iv,
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Core::HEADER_VERSION_SIZE + Core::SALT_BYTE_SIZE + $ivsize
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);
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/* Add the header, salt, and IV to the HMAC. */
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\hash_update($hmac, Core::CURRENT_VERSION);
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\hash_update($hmac, $file_salt);
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\hash_update($hmac, $iv);
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/* $thisIv will be incremented after each call to the encryption. */
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$thisIv = $iv;
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/* How many blocks do we encrypt at a time? We increment by this value. */
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/**
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* @psalm-suppress RedundantCast
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*/
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$inc = (int) (Core::BUFFER_BYTE_SIZE / Core::BLOCK_BYTE_SIZE);
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/* Loop until we reach the end of the input file. */
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$at_file_end = false;
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while (! (\feof($inputHandle) || $at_file_end)) {
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/* Find out if we can read a full buffer, or only a partial one. */
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/** @var int */
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$pos = \ftell($inputHandle);
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if (!\is_int($pos)) {
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throw new Ex\IOException(
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'Could not get current position in input file during encryption'
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);
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}
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if ($pos + Core::BUFFER_BYTE_SIZE >= $inputSize) {
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/* We're at the end of the file, so we need to break out of the loop. */
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|
|
$at_file_end = true;
|
||
|
|
$read = self::readBytes(
|
||
|
|
$inputHandle,
|
||
|
|
$inputSize - $pos
|
||
|
|
);
|
||
|
|
} else {
|
||
|
|
$read = self::readBytes(
|
||
|
|
$inputHandle,
|
||
|
|
Core::BUFFER_BYTE_SIZE
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Encrypt this buffer. */
|
||
|
|
/** @var string */
|
||
|
|
$encrypted = \openssl_encrypt(
|
||
|
|
$read,
|
||
|
|
Core::CIPHER_METHOD,
|
||
|
|
$ekey,
|
||
|
|
OPENSSL_RAW_DATA,
|
||
|
|
$thisIv
|
||
|
|
);
|
||
|
|
|
||
|
|
Core::ensureTrue(\is_string($encrypted), 'OpenSSL encryption error');
|
||
|
|
|
||
|
|
/* Write this buffer's ciphertext. */
|
||
|
|
self::writeBytes($outputHandle, $encrypted, Core::ourStrlen($encrypted));
|
||
|
|
/* Add this buffer's ciphertext to the HMAC. */
|
||
|
|
\hash_update($hmac, $encrypted);
|
||
|
|
|
||
|
|
/* Increment the counter by the number of blocks in a buffer. */
|
||
|
|
$thisIv = Core::incrementCounter($thisIv, $inc);
|
||
|
|
/* WARNING: Usually, unless the file is a multiple of the buffer
|
||
|
|
* size, $thisIv will contain an incorrect value here on the last
|
||
|
|
* iteration of this loop. */
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Get the HMAC and append it to the ciphertext. */
|
||
|
|
$final_mac = \hash_final($hmac, true);
|
||
|
|
self::writeBytes($outputHandle, $final_mac, Core::MAC_BYTE_SIZE);
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Decrypts a file-backed resource with either a key or a password.
|
||
|
|
*
|
||
|
|
* @param resource $inputHandle
|
||
|
|
* @param resource $outputHandle
|
||
|
|
* @param KeyOrPassword $secret
|
||
|
|
* @return void
|
||
|
|
*
|
||
|
|
* @throws Ex\EnvironmentIsBrokenException
|
||
|
|
* @throws Ex\IOException
|
||
|
|
* @throws Ex\WrongKeyOrModifiedCiphertextException
|
||
|
|
* @psalm-suppress PossiblyInvalidArgument
|
||
|
|
* Fixes erroneous errors caused by PHP 7.2 switching the return value
|
||
|
|
* of hash_init from a resource to a HashContext.
|
||
|
|
*/
|
||
|
|
public static function decryptResourceInternal($inputHandle, $outputHandle, KeyOrPassword $secret)
|
||
|
|
{
|
||
|
|
if (! \is_resource($inputHandle)) {
|
||
|
|
throw new Ex\IOException(
|
||
|
|
'Input handle must be a resource!'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
if (! \is_resource($outputHandle)) {
|
||
|
|
throw new Ex\IOException(
|
||
|
|
'Output handle must be a resource!'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Make sure the file is big enough for all the reads we need to do. */
|
||
|
|
$stat = \fstat($inputHandle);
|
||
|
|
if ($stat['size'] < Core::MINIMUM_CIPHERTEXT_SIZE) {
|
||
|
|
throw new Ex\WrongKeyOrModifiedCiphertextException(
|
||
|
|
'Input file is too small to have been created by this library.'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Check the version header. */
|
||
|
|
$header = self::readBytes($inputHandle, Core::HEADER_VERSION_SIZE);
|
||
|
|
if ($header !== Core::CURRENT_VERSION) {
|
||
|
|
throw new Ex\WrongKeyOrModifiedCiphertextException(
|
||
|
|
'Bad version header.'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Get the salt. */
|
||
|
|
$file_salt = self::readBytes($inputHandle, Core::SALT_BYTE_SIZE);
|
||
|
|
|
||
|
|
/* Get the IV. */
|
||
|
|
$ivsize = Core::BLOCK_BYTE_SIZE;
|
||
|
|
$iv = self::readBytes($inputHandle, $ivsize);
|
||
|
|
|
||
|
|
/* Derive the authentication and encryption keys. */
|
||
|
|
$keys = $secret->deriveKeys($file_salt);
|
||
|
|
$ekey = $keys->getEncryptionKey();
|
||
|
|
$akey = $keys->getAuthenticationKey();
|
||
|
|
|
||
|
|
/* We'll store the MAC of each buffer-sized chunk as we verify the
|
||
|
|
* actual MAC, so that we can check them again when decrypting. */
|
||
|
|
$macs = [];
|
||
|
|
|
||
|
|
/* $thisIv will be incremented after each call to the decryption. */
|
||
|
|
$thisIv = $iv;
|
||
|
|
|
||
|
|
/* How many blocks do we encrypt at a time? We increment by this value. */
|
||
|
|
/**
|
||
|
|
* @psalm-suppress RedundantCast
|
||
|
|
*/
|
||
|
|
$inc = (int) (Core::BUFFER_BYTE_SIZE / Core::BLOCK_BYTE_SIZE);
|
||
|
|
|
||
|
|
/* Get the HMAC. */
|
||
|
|
if (\fseek($inputHandle, (-1 * Core::MAC_BYTE_SIZE), SEEK_END) === -1) {
|
||
|
|
throw new Ex\IOException(
|
||
|
|
'Cannot seek to beginning of MAC within input file'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Get the position of the last byte in the actual ciphertext. */
|
||
|
|
/** @var int $cipher_end */
|
||
|
|
$cipher_end = \ftell($inputHandle);
|
||
|
|
if (!\is_int($cipher_end)) {
|
||
|
|
throw new Ex\IOException(
|
||
|
|
'Cannot read input file'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
/* We have the position of the first byte of the HMAC. Go back by one. */
|
||
|
|
--$cipher_end;
|
||
|
|
|
||
|
|
/* Read the HMAC. */
|
||
|
|
/** @var string $stored_mac */
|
||
|
|
$stored_mac = self::readBytes($inputHandle, Core::MAC_BYTE_SIZE);
|
||
|
|
|
||
|
|
/* Initialize a streaming HMAC state. */
|
||
|
|
/** @var mixed $hmac */
|
||
|
|
$hmac = \hash_init(Core::HASH_FUNCTION_NAME, HASH_HMAC, $akey);
|
||
|
|
Core::ensureTrue(\is_resource($hmac) || \is_object($hmac), 'Cannot initialize a hash context');
|
||
|
|
|
||
|
|
/* Reset file pointer to the beginning of the file after the header */
|
||
|
|
if (\fseek($inputHandle, Core::HEADER_VERSION_SIZE, SEEK_SET) === -1) {
|
||
|
|
throw new Ex\IOException(
|
||
|
|
'Cannot read seek within input file'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Seek to the start of the actual ciphertext. */
|
||
|
|
if (\fseek($inputHandle, Core::SALT_BYTE_SIZE + $ivsize, SEEK_CUR) === -1) {
|
||
|
|
throw new Ex\IOException(
|
||
|
|
'Cannot seek input file to beginning of ciphertext'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* PASS #1: Calculating the HMAC. */
|
||
|
|
|
||
|
|
\hash_update($hmac, $header);
|
||
|
|
\hash_update($hmac, $file_salt);
|
||
|
|
\hash_update($hmac, $iv);
|
||
|
|
/** @var mixed $hmac2 */
|
||
|
|
$hmac2 = \hash_copy($hmac);
|
||
|
|
|
||
|
|
$break = false;
|
||
|
|
while (! $break) {
|
||
|
|
/** @var int $pos */
|
||
|
|
$pos = \ftell($inputHandle);
|
||
|
|
if (!\is_int($pos)) {
|
||
|
|
throw new Ex\IOException(
|
||
|
|
'Could not get current position in input file during decryption'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Read the next buffer-sized chunk (or less). */
|
||
|
|
if ($pos + Core::BUFFER_BYTE_SIZE >= $cipher_end) {
|
||
|
|
$break = true;
|
||
|
|
$read = self::readBytes(
|
||
|
|
$inputHandle,
|
||
|
|
$cipher_end - $pos + 1
|
||
|
|
);
|
||
|
|
} else {
|
||
|
|
$read = self::readBytes(
|
||
|
|
$inputHandle,
|
||
|
|
Core::BUFFER_BYTE_SIZE
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Update the HMAC. */
|
||
|
|
\hash_update($hmac, $read);
|
||
|
|
|
||
|
|
/* Remember this buffer-sized chunk's HMAC. */
|
||
|
|
/** @var mixed $chunk_mac */
|
||
|
|
$chunk_mac = \hash_copy($hmac);
|
||
|
|
Core::ensureTrue(\is_resource($chunk_mac) || \is_object($chunk_mac), 'Cannot duplicate a hash context');
|
||
|
|
$macs []= \hash_final($chunk_mac);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Get the final HMAC, which should match the stored one. */
|
||
|
|
/** @var string $final_mac */
|
||
|
|
$final_mac = \hash_final($hmac, true);
|
||
|
|
|
||
|
|
/* Verify the HMAC. */
|
||
|
|
if (! Core::hashEquals($final_mac, $stored_mac)) {
|
||
|
|
throw new Ex\WrongKeyOrModifiedCiphertextException(
|
||
|
|
'Integrity check failed.'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* PASS #2: Decrypt and write output. */
|
||
|
|
|
||
|
|
/* Rewind to the start of the actual ciphertext. */
|
||
|
|
if (\fseek($inputHandle, Core::SALT_BYTE_SIZE + $ivsize + Core::HEADER_VERSION_SIZE, SEEK_SET) === -1) {
|
||
|
|
throw new Ex\IOException(
|
||
|
|
'Could not move the input file pointer during decryption'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
$at_file_end = false;
|
||
|
|
while (! $at_file_end) {
|
||
|
|
/** @var int $pos */
|
||
|
|
$pos = \ftell($inputHandle);
|
||
|
|
if (!\is_int($pos)) {
|
||
|
|
throw new Ex\IOException(
|
||
|
|
'Could not get current position in input file during decryption'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Read the next buffer-sized chunk (or less). */
|
||
|
|
if ($pos + Core::BUFFER_BYTE_SIZE >= $cipher_end) {
|
||
|
|
$at_file_end = true;
|
||
|
|
$read = self::readBytes(
|
||
|
|
$inputHandle,
|
||
|
|
$cipher_end - $pos + 1
|
||
|
|
);
|
||
|
|
} else {
|
||
|
|
$read = self::readBytes(
|
||
|
|
$inputHandle,
|
||
|
|
Core::BUFFER_BYTE_SIZE
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Recalculate the MAC (so far) and compare it with the one we
|
||
|
|
* remembered from pass #1 to ensure attackers didn't change the
|
||
|
|
* ciphertext after MAC verification. */
|
||
|
|
\hash_update($hmac2, $read);
|
||
|
|
/** @var mixed $calc_mac */
|
||
|
|
$calc_mac = \hash_copy($hmac2);
|
||
|
|
Core::ensureTrue(\is_resource($calc_mac) || \is_object($calc_mac), 'Cannot duplicate a hash context');
|
||
|
|
$calc = \hash_final($calc_mac);
|
||
|
|
|
||
|
|
if (empty($macs)) {
|
||
|
|
throw new Ex\WrongKeyOrModifiedCiphertextException(
|
||
|
|
'File was modified after MAC verification'
|
||
|
|
);
|
||
|
|
} elseif (! Core::hashEquals(\array_shift($macs), $calc)) {
|
||
|
|
throw new Ex\WrongKeyOrModifiedCiphertextException(
|
||
|
|
'File was modified after MAC verification'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Decrypt this buffer-sized chunk. */
|
||
|
|
/** @var string $decrypted */
|
||
|
|
$decrypted = \openssl_decrypt(
|
||
|
|
$read,
|
||
|
|
Core::CIPHER_METHOD,
|
||
|
|
$ekey,
|
||
|
|
OPENSSL_RAW_DATA,
|
||
|
|
$thisIv
|
||
|
|
);
|
||
|
|
Core::ensureTrue(\is_string($decrypted), 'OpenSSL decryption error');
|
||
|
|
|
||
|
|
/* Write the plaintext to the output file. */
|
||
|
|
self::writeBytes(
|
||
|
|
$outputHandle,
|
||
|
|
$decrypted,
|
||
|
|
Core::ourStrlen($decrypted)
|
||
|
|
);
|
||
|
|
|
||
|
|
/* Increment the IV by the amount of blocks in a buffer. */
|
||
|
|
/** @var string $thisIv */
|
||
|
|
$thisIv = Core::incrementCounter($thisIv, $inc);
|
||
|
|
/* WARNING: Usually, unless the file is a multiple of the buffer
|
||
|
|
* size, $thisIv will contain an incorrect value here on the last
|
||
|
|
* iteration of this loop. */
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Read from a stream; prevent partial reads.
|
||
|
|
*
|
||
|
|
* @param resource $stream
|
||
|
|
* @param int $num_bytes
|
||
|
|
* @return string
|
||
|
|
*
|
||
|
|
* @throws Ex\IOException
|
||
|
|
* @throws Ex\EnvironmentIsBrokenException
|
||
|
|
*/
|
||
|
|
public static function readBytes($stream, $num_bytes)
|
||
|
|
{
|
||
|
|
Core::ensureTrue($num_bytes >= 0, 'Tried to read less than 0 bytes');
|
||
|
|
|
||
|
|
if ($num_bytes === 0) {
|
||
|
|
return '';
|
||
|
|
}
|
||
|
|
|
||
|
|
$buf = '';
|
||
|
|
$remaining = $num_bytes;
|
||
|
|
while ($remaining > 0 && ! \feof($stream)) {
|
||
|
|
/** @var string $read */
|
||
|
|
$read = \fread($stream, $remaining);
|
||
|
|
if (!\is_string($read)) {
|
||
|
|
throw new Ex\IOException(
|
||
|
|
'Could not read from the file'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
$buf .= $read;
|
||
|
|
$remaining -= Core::ourStrlen($read);
|
||
|
|
}
|
||
|
|
if (Core::ourStrlen($buf) !== $num_bytes) {
|
||
|
|
throw new Ex\IOException(
|
||
|
|
'Tried to read past the end of the file'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
return $buf;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Write to a stream; prevents partial writes.
|
||
|
|
*
|
||
|
|
* @param resource $stream
|
||
|
|
* @param string $buf
|
||
|
|
* @param int $num_bytes
|
||
|
|
* @return int
|
||
|
|
*
|
||
|
|
* @throws Ex\IOException
|
||
|
|
*/
|
||
|
|
public static function writeBytes($stream, $buf, $num_bytes = null)
|
||
|
|
{
|
||
|
|
$bufSize = Core::ourStrlen($buf);
|
||
|
|
if ($num_bytes === null) {
|
||
|
|
$num_bytes = $bufSize;
|
||
|
|
}
|
||
|
|
if ($num_bytes > $bufSize) {
|
||
|
|
throw new Ex\IOException(
|
||
|
|
'Trying to write more bytes than the buffer contains.'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
if ($num_bytes < 0) {
|
||
|
|
throw new Ex\IOException(
|
||
|
|
'Tried to write less than 0 bytes'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
$remaining = $num_bytes;
|
||
|
|
while ($remaining > 0) {
|
||
|
|
/** @var int $written */
|
||
|
|
$written = \fwrite($stream, $buf, $remaining);
|
||
|
|
if (!\is_int($written)) {
|
||
|
|
throw new Ex\IOException(
|
||
|
|
'Could not write to the file'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
$buf = (string) Core::ourSubstr($buf, $written, null);
|
||
|
|
$remaining -= $written;
|
||
|
|
}
|
||
|
|
return $num_bytes;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Returns the last PHP error's or warning's message string.
|
||
|
|
*
|
||
|
|
* @return string
|
||
|
|
*/
|
||
|
|
private static function getLastErrorMessage()
|
||
|
|
{
|
||
|
|
$error = error_get_last();
|
||
|
|
if ($error === null) {
|
||
|
|
return '[no PHP error]';
|
||
|
|
} else {
|
||
|
|
return $error['message'];
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|