(PHP ActiveX) Streaming Encryption

Encrypt and decrypt using a stream.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows Note: The php_com_dotnet.dll may need to be enabled inside of php.ini.

<?php

// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.Crypt2')
$crypt = new COM("Chilkat.Crypt2");

// Setup encryption using the chacha20 algorithm...
$crypt->CryptAlgorithm = 'chacha20';
$crypt->KeyLength = 256;
$crypt->EncodingMode = 'hex';
$ivHex = '000000000000000000000002';
$crypt->SetEncodedIV($ivHex,'hex');
$crypt->InitialCount = 42;
$keyHex = '1c9240a5eb55d38af333888604f6b5f0473917c1402b80099dca5cbc207075c0';
$crypt->SetEncodedKey($keyHex,'hex');

$plainText = 'The quick brown fox jumped over the lazy dog.\r\n';

// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.Stream')
$stream = new COM("Chilkat.Stream");

// We'll save the encrypted output in eStrings to demonstrate streaming decryption next.
// For versions of Chilkat < 10.0.0, use new COM('Chilkat_9_5_0.Chilkat.StringArray')
$eStrings = new COM("Chilkat.StringArray");

// Start a background task that will encrypt a stream.
// task is a Chilkat.Task
$task = $crypt->EncryptStreamAsync($stream);
$success = $task->Run();

// Write plainText to the stream, and read chacha20 encrypted text..

for ($i = 1; $i <= 10; $i++) {
    // Note: An encryption algorithm's block size will cause buffering,
    // and therefore not every loop iteration will produce output.
    $success = $stream->WriteString($plainText);
    if ($stream->DataAvailable == 1) {
        $cipherText = $stream->readBytesENC('hex');
        print $cipherText . "\n";
        $success = $eStrings->Append($cipherText);
    }

}

// Tell the background task that the stream has ended.
$success = $stream->WriteClose();

// Let's make sure the background task finished.
// It should already be the case that the task is finished.
while (($task->Finished != 1)) {
    $task->SleepMs(20);
}

// Get any remaining data available from the stream.
if ($stream->DataAvailable == 1) {
    $cipherText = $stream->readBytesENC('hex');
    print $cipherText . "\n";
    $success = $eStrings->Append($cipherText);
}

if ($task->TaskSuccess != 1) {
    print 'async encryption failed:' . "\n";
    print $task->ResultErrorText . "\n";
    $success = 0;
}

print '-- encrypt finished --' . "\n";

// Now decrypt to return the original.

// Reset the stream object so it can be used again.
$stream->Reset();

// Start a background task that will decrypt a stream.
// task is a Chilkat.Task
$task = $crypt->DecryptStreamAsync($stream);
$success = $task->Run();

$n = $eStrings->Count;
for ($i = 0; $i <= $n - 1; $i++) {
    $success = $stream->WriteBytesENC($eStrings->getString($i),'hex');
    if ($stream->DataAvailable == 1) {
        $plainText = $stream->readString();
        print $plainText . "\n";
    }

}

// Tell the background task that the stream has ended.
$success = $stream->WriteClose();

// Let's make sure the background task finished.
// It should already be the case that the task is finished.
while (($task->Finished != 1)) {
    $task->SleepMs(20);
}

// Get any remaining data available from the stream.
if ($stream->DataAvailable == 1) {
    $plainText = $stream->readString();
    print $plainText . "\n";
}

if ($task->TaskSuccess != 1) {
    print 'async decryption failed:' . "\n";
    print $task->ResultErrorText . "\n";
    $success = 0;
}

print '-- decrypt finished --' . "\n";

?>