protocol_client_loopback_test

This is used to confirm that SSL client connections can coexist with
a vhost doing serving.

To set it up,

/*
 * This is a bit fiddly...
 *
 * 0) If you want the wss:// test to work, make sure the vhost is marked with
 *    enable-client-ssl if using lwsws, or call lws_init_vhost_client_ssl() on
 *    the vhost if you're doing it by hand.
 *
 * 1) enable the protocol on a vhost
 *
 *      "ws-protocols": [{
 *     "client-loopback-test": {
 *      "status": "ok"
 *     },  ...
 *
 *     the vhost should listen on 80 (ws://) or 443 (wss://)
 *
 * 2) mount the http part of the test one level down on the same vhost, eg
 *   {
 *      "mountpoint": "/c",
 *      "origin": "callback://client-loopback-test"
 *   }
 *
 * 3) Use a browser to visit the mountpoint with a URI attached for looping
 *    back, eg, if testing on localhost
 *
 *    http://localhost/c/ws://localhost
 *    https://localhost/c/wss://localhost
 *
 * 4) The HTTP part of this test protocol will try to do the requested
 *    ws client connection, to the same test protocol on the same
 *    server.
 */

Results should look like this

lwsws[29938]: client connection to localhost:443 with ssl: 1 started
lwsws[29938]: server part: LWS_CALLBACK_ESTABLISHED
lwsws[29938]: checking client ext permessage-deflate
lwsws[29938]: instantiating client ext permessage-deflate
lwsws[29938]: Client connection established
lwsws[29938]: Client connection received 7 from server 'Made it'

Signed-off-by: Andy Green <andy@warmcat.com>

CMakeLists.txt

@@ -1231,6 +1231,12 @@ if (LWS_WITH_SERVER_STATUS)
 		create_plugin(protocol_lws_server_status
 			      "plugins/protocol_lws_server_status.c")
 endif()
+
+if (NOT LWS_WITHOUT_CLIENT)
+		create_plugin(protocol_client_loopback_test
+                              "plugins/protocol_client_loopback_test.c")
+endif(NOT LWS_WITHOUT_CLIENT)
+
 	endif(LWS_WITH_PLUGINS AND LWS_WITH_SHARED)
 
 	#

plugins/protocol_client_loopback_test.c

@@ -0,0 +1,194 @@
+/*
+ * ws protocol handler plugin for "client_loopback_test"
+ *
+ * Copyright (C) 2010-2016 Andy Green <andy@warmcat.com>
+ *
+ * This file is made available under the Creative Commons CC0 1.0
+ * Universal Public Domain Dedication.
+ *
+ * The person who associated a work with this deed has dedicated
+ * the work to the public domain by waiving all of his or her rights
+ * to the work worldwide under copyright law, including all related
+ * and neighboring rights, to the extent allowed by law. You can copy,
+ * modify, distribute and perform the work, even for commercial purposes,
+ * all without asking permission.
+ *
+ * These test plugins are intended to be adapted for use in your code, which
+ * may be proprietary.  So unlike the library itself, they are licensed
+ * Public Domain.
+ */
+#include "../lib/libwebsockets.h"
+#include <string.h>
+
+struct per_session_data__client_loopback_test {
+	struct lws *wsi;
+};
+
+/*
+ * This is a bit fiddly...
+ *
+ * 0) If you want the wss:// test to work, make sure the vhost is marked with
+ *    enable-client-ssl if using lwsws, or call lws_init_vhost_client_ssl() on
+ *    the vhost if you're doing it by hand.
+ *
+ * 1) enable the protocol on a vhost
+ *
+ *      "ws-protocols": [{
+ *     "client-loopback-test": {
+ *      "status": "ok"
+ *     },  ...
+ *
+ *     the vhost should listen on 80 (ws://) or 443 (wss://)
+ *
+ * 2) mount the http part of the test one level down on the same vhost, eg
+ *   {
+ *      "mountpoint": "/c",
+ *      "origin": "callback://client-loopback-test"
+ *   }
+ *
+ * 3) Use a browser to visit the mountpoint with a URI attached for looping
+ *    back, eg, if testing on localhost
+ *
+ *    http://localhost/c/ws://localhost
+ *    https://localhost/c/wss://localhost
+ *
+ * 4) The HTTP part of this test protocol will try to do the requested
+ *    ws client connection, to the same test protocol on the same
+ *    server.
+ */
+
+static int
+callback_client_loopback_test(struct lws *wsi, enum lws_callback_reasons reason,
+			void *user, void *in, size_t len)
+{
+	struct lws_client_connect_info i;
+	struct per_session_data__client_loopback_test *pss =
+			(struct per_session_data__client_loopback_test *)user;
+	const char *p = (const char *)in;
+	char buf[100];
+	int n;
+
+	switch (reason) {
+
+	/* HTTP part */
+
+	case LWS_CALLBACK_HTTP:
+		if (len < 10)
+			return -1;
+
+		p++;
+		while (*p && *p != '/')
+			p++;
+		if (!*p) {
+			lws_return_http_status(wsi, 400, "Arg needs to be in format ws://xxx or wss://xxx");
+			return -1;
+		}
+		p++;
+
+		memset(&i, 0, sizeof(i));
+		i.context = lws_get_context(wsi);
+
+		// stacked /// get resolved to /
+
+		if (strncmp(p, "ws:/", 4) == 0) {
+			i.ssl_connection = 0;
+			i.port = 80;
+			p += 4;
+		} else
+			if (strncmp(p, "wss:/", 5) == 0) {
+				i.port = 443;
+				i.ssl_connection = 1;
+				p += 5;
+			} else {
+				sprintf(buf, "Arg %s is not in format ws://xxx or wss://xxx\n", p);
+				lws_return_http_status(wsi, 400, buf);
+				return -1;
+			}
+
+		i.address = p;
+		i.path = "";
+		i.host = p;
+		i.origin = p;
+		i.ietf_version_or_minus_one = -1;
+		i.protocol = "client-loopback-test";
+
+		pss->wsi = lws_client_connect_via_info(&i);
+		if (!pss->wsi)
+			lws_return_http_status(wsi, 401, "client-loopback-test: connect failed\n");
+		else {
+			lwsl_notice("client connection to %s:%d with ssl: %d started\n",
+				    i.address, i.port, i.ssl_connection);
+			lws_return_http_status(wsi, 200, "OK");
+		}
+
+		/* either way, close the triggering http link */
+
+		return -1;
+
+	case LWS_CALLBACK_CLOSED_HTTP:
+		lwsl_notice("Http part closed\n");
+		break;
+
+	/* server part */
+
+	case LWS_CALLBACK_ESTABLISHED:
+		lwsl_notice("server part: LWS_CALLBACK_ESTABLISHED\n");
+		strcpy(buf + LWS_PRE, "Made it");
+		n = lws_write(wsi, (unsigned char *)buf + LWS_PRE,
+			      7, LWS_WRITE_TEXT);
+		if (n < 7)
+			return -1;
+		break;
+
+	/* client part */
+
+	case LWS_CALLBACK_CLIENT_ESTABLISHED:
+		lwsl_notice("Client connection established\n");
+		break;
+
+	case LWS_CALLBACK_CLIENT_RECEIVE:
+		strncpy(buf, in, sizeof(buf) - 1);
+		lwsl_notice("Client connection received %d from server '%s'\n", len, buf);
+
+		/* OK we are done with the client connection */
+		return -1;
+
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static const struct lws_protocols protocols[] = {
+	{
+		"client-loopback-test",
+		callback_client_loopback_test,
+		sizeof(struct per_session_data__client_loopback_test),
+		1024, /* rx buf size must be >= permessage-deflate rx size */
+	},
+};
+
+LWS_VISIBLE int
+init_protocol_client_loopback_test(struct lws_context *context,
+				   struct lws_plugin_capability *c)
+{
+	if (c->api_magic != LWS_PLUGIN_API_MAGIC) {
+		lwsl_err("Plugin API %d, library API %d", LWS_PLUGIN_API_MAGIC,
+			 c->api_magic);
+		return 1;
+	}
+
+	c->protocols = protocols;
+	c->count_protocols = ARRAY_SIZE(protocols);
+	c->extensions = NULL;
+	c->count_extensions = 0;
+
+	return 0;
+}
+
+LWS_VISIBLE int
+destroy_protocol_client_loopback_test(struct lws_context *context)
+{
+	return 0;
+}