(PHP 5 >= 5.1.0, PHP 7, PHP 8)
stream_socket_enable_crypto — Turns encryption on/off on an already connected socket
$stream,$enable,$crypto_method = null,$session_stream = nullEnable or disable encryption on the stream.
Once the crypto settings are established, cryptography can be turned
on and off dynamically by passing true or false in the
enable parameter.
streamThe stream resource.
enableEnable/disable cryptography on the stream.
crypto_methodSetup encryption on the stream. Valid methods are
STREAM_CRYPTO_METHOD_SSLv2_CLIENTSTREAM_CRYPTO_METHOD_SSLv3_CLIENTSTREAM_CRYPTO_METHOD_SSLv23_CLIENTSTREAM_CRYPTO_METHOD_ANY_CLIENTSTREAM_CRYPTO_METHOD_TLS_CLIENTSTREAM_CRYPTO_METHOD_TLSv1_0_CLIENTSTREAM_CRYPTO_METHOD_TLSv1_1_CLIENTSTREAM_CRYPTO_METHOD_TLSv1_2_CLIENTSTREAM_CRYPTO_METHOD_TLSv1_3_CLIENT (as of PHP 7.4.0)STREAM_CRYPTO_METHOD_SSLv2_SERVERSTREAM_CRYPTO_METHOD_SSLv3_SERVERSTREAM_CRYPTO_METHOD_SSLv23_SERVERSTREAM_CRYPTO_METHOD_ANY_SERVERSTREAM_CRYPTO_METHOD_TLS_SERVERSTREAM_CRYPTO_METHOD_TLSv1_0_SERVERSTREAM_CRYPTO_METHOD_TLSv1_1_SERVERSTREAM_CRYPTO_METHOD_TLSv1_2_SERVERSTREAM_CRYPTO_METHOD_TLSv1_3_SERVER (as of PHP 7.4.0)
If omitted, the crypto_method context option on
the stream's SSL context will be used instead.
session_stream
Seed the stream with settings from session_stream.
Returns true on success, false if negotiation has failed or
0 if there isn't enough data and you should try again
(only for non-blocking sockets).
| Version | Description |
|---|---|
| 8.0.0 |
session_stream is now nullable.
|
Example #1 stream_socket_enable_crypto() example
<?php
$fp = stream_socket_client("tcp://myproto.example.com:31337", $errno, $errstr, 30);
if (!$fp) {
die("Unable to connect: $errstr ($errno)");
}
/* Turn on encryption for login phase */
stream_socket_enable_crypto($fp, true, STREAM_CRYPTO_METHOD_SSLv23_CLIENT);
fwrite($fp, "USER god\r\n");
fwrite($fp, "PASS secret\r\n");
/* Turn off encryption for the rest */
stream_socket_enable_crypto($fp, false);
while ($motd = fgets($fp)) {
echo $motd;
}
fclose($fp);
?>The above example will output something similar to:
If you need to change a stream from unencrypted to crypted after unencrypted traffic has been processed, you use the stream-socket-recvfrom function to read instead of fread when reading the unencrypted traffic. Using fread will cause some of the buffer of the initial CLIENT HELLO message to be read into it's buffers causing the SSL handshake to fail in some situations.As already mentioned above:
stream_socket_enable_crypto is likely to fail/return zero if the socket is in non-blocking mode.
You may either wait some seconds until all neccessary data has arrived or switch temporary to blocking mode:
<?PHP
stream_set_blocking ($fd, true);
stream_socket_enable_crypto ($fd, true, STREAM_CRYPTO_METHOD_TLS_CLIENT);
stream_set_blocking ($fd, false);
?>
This works very fine for me ;-)Information to the difference of `crypto_method`
There is `STREAM_CRYPTO_METHOD_*_CLIENT` and `STREAM_CRYPTO_METHOD_*_SERVER`
`STREAM_CRYPTO_METHOD_*_CLIENT` is used for clients, like:
```php
<?php
$client = stream_socket_client("tcp://example.com:443", $errno, $errstr);
stream_socket_enable_crypto($client, true, STREAM_CRYPTO_METHOD_TLS_CLIENT);
//...
?>
```
This code makes a TLS Handshake and the `stream_socket_enable_crypto` sends a `Client HELLO`
`STREAM_CRYPTO_METHOD_*_SERVER` is used for servers, like:
<?php
$server = stream_socket_server("tcp://example.com:443", $errno, $errstr, STREAM_SERVER_BIND | STREAM_SERVER_LISTEN);
stream_context_set_option($server, ["ssl" => [
"local_cert" => __DIR__."/https.crt",
"local_pk" => __DIR__."/https.key",
]]);
//...
$client = stream_socket_accept($server);
stream_socket_enable_crypto($client, true, STREAM_CRYPTO_METHOD_TLS_SERVER);
//...
?>
This code makes a TLS Handshake and the `stream_socket_enable_crypto` sends a `Server HELLO` after the client send a `Client HELLO`.
so use `STREAM_CRYPTO_METHOD_*_CLIENT` for requesting data and `STREAM_CRYPTO_METHOD_*_SERVER` for serving data, after accepting a client.