/*
* ws protocol handler plugin for testing raw file and raw socket
*
* Copyright (C) 2010-2017 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.
*
* This plugin test both raw file descriptors and raw socket descriptors. It
* can test both or just one depending on how you configure it. libwebsockets-
* test-server-v2.0 is set up to test both.
*
* RAW File Descriptor Testing
* ===========================
*
* Enable on a vhost like this
*
* "protocol-lws-raw-test": {
* "status": "ok",
* "fifo-path": "/tmp/lws-test-raw"
* },
*
* Then you can feed it data through the FIFO like this
*
* $ sudo sh -c "echo hello > /tmp/lws-test-raw"
*
* This plugin simply prints the data. But it does it through the lws event
* loop / service poll.
*
*
* RAW Socket Descriptor Testing
* =============================
*
* 1) You must give the vhost the option flag LWS_SERVER_OPTION_FALLBACK_TO_RAW
*
* 2) Enable on a vhost like this
*
* "protocol-lws-raw-test": {
* "status": "ok",
* "raw": "1"
* },
*
* The "raw" pvo marks this protocol as being used for RAW connections.
*
* 3) Run libwebsockets-test-server-v2.0 and connect to it by telnet, eg
*
* telnet 127.0.0.1 7681
*
* type something that isn't a valid HTTP method and enter, before the
* connection times out. The connection will switch to RAW mode using this
* protocol, and pass the unused rx as a raw RX callback.
*
* The test protocol echos back what was typed on telnet to telnet.
*/
#if !defined (LWS_PLUGIN_STATIC)
#define LWS_DLL
#define LWS_INTERNAL
#include "../lib/libwebsockets.h"
#endif
#include <string.h>
struct per_vhost_data__raw_test {
struct lws_context *context;
struct lws_vhost *vhost;
const struct lws_protocols *protocol;
char fifo_path[100];
int fifo;
char zero_length_read;
};
struct per_session_data__raw_test {
int number;
unsigned char buf[128];
int len;
};
static int
callback_raw_test(struct lws *wsi, enum lws_callback_reasons reason,
void *user, void *in, size_t len)
{
struct per_session_data__raw_test *pss =
(struct per_session_data__raw_test *)user;
struct per_vhost_data__raw_test *vhd =
(struct per_vhost_data__raw_test *)
lws_protocol_vh_priv_get(lws_get_vhost(wsi),
lws_get_protocol(wsi));
lws_sock_file_fd_type u;
(void)pss;
switch (reason) {
case LWS_CALLBACK_PROTOCOL_INIT:
vhd = lws_protocol_vh_priv_zalloc(lws_get_vhost(wsi),
lws_get_protocol(wsi),
sizeof(struct per_vhost_data__raw_test));
vhd->context = lws_get_context(wsi);
vhd->protocol = lws_get_protocol(wsi);
vhd->vhost = lws_get_vhost(wsi);
{
const struct lws_protocol_vhost_options *pvo =
(const struct lws_protocol_vhost_options *)in;
while (pvo) {
if (!strcmp(pvo->name, "fifo-path"))
lws_strncpy(vhd->fifo_path, pvo->value,
sizeof(vhd->fifo_path));
pvo = pvo->next;
}
if (vhd->fifo_path[0] == '\0') {
lwsl_err("%s: Missing pvo \"fifo-path\", raw file fd testing disabled\n", __func__);
break;
}
}
unlink(vhd->fifo_path);
if (mkfifo(vhd->fifo_path, 0666)) {
lwsl_err("mkfifo failed\n");
return 1;
}
vhd->fifo = open(vhd->fifo_path, O_NONBLOCK | O_RDONLY);
if (vhd->fifo == -1) {
lwsl_err("opening fifo failed\n");
unlink(vhd->fifo_path);
return 1;
}
lwsl_notice("FIFO %s created\n", vhd->fifo_path);
u.filefd = vhd->fifo;
if (!lws_adopt_descriptor_vhost(vhd->vhost,
LWS_ADOPT_RAW_FILE_DESC, u,
"protocol-lws-raw-test",
NULL)) {
lwsl_err("Failed to adopt fifo descriptor\n");
close(vhd->fifo);
unlink(vhd->fifo_path);
return 1;
}
break;
case LWS_CALLBACK_PROTOCOL_DESTROY:
if (!vhd)
break;
if (vhd->fifo >= 0) {
close(vhd->fifo);
unlink(vhd->fifo_path);
}
break;
/*
* Callbacks related to Raw file descriptor testing
*/
case LWS_CALLBACK_RAW_ADOPT_FILE:
lwsl_notice("LWS_CALLBACK_RAW_ADOPT_FILE\n");
break;
case LWS_CALLBACK_RAW_RX_FILE:
lwsl_notice("LWS_CALLBACK_RAW_RX_FILE\n");
{
char buf[256];
int n;
n = read(vhd->fifo, buf, sizeof(buf) - 1);
if (n < 0) {
lwsl_err("FIFO read failed\n");
return 1;
}
/*
* When nobody opened the other side of the FIFO, the FIFO fd acts well and
* only signals POLLIN when somebody opened and wrote to it.
*
* But if the other side of the FIFO closed it, we will see an endless
* POLLIN and 0 available to read.
*
* The only way to handle it is to reopen the FIFO our side and wait for a
* new peer. This is a quirk of FIFOs not of LWS.
*/
if (n == 0) { /* peer closed - do reopen in close processing */
vhd->zero_length_read = 1;
return 1;
}
buf[n] = '\0';
lwsl_info("read %d\n", n);
puts(buf);
}
break;
case LWS_CALLBACK_RAW_CLOSE_FILE:
lwsl_notice("LWS_CALLBACK_RAW_CLOSE_FILE\n");
if (vhd->zero_length_read) {
vhd->zero_length_read = 0;
close(vhd->fifo);
/* the wsi that adopted the fifo file is closing... reopen the fifo and readopt */
vhd->fifo = open(vhd->fifo_path, O_NONBLOCK | O_RDONLY);
if (vhd->fifo == -1) {
lwsl_err("opening fifo failed\n");
return 1;
}
lwsl_notice("FIFO %s reopened\n", vhd->fifo_path);
u.filefd = vhd->fifo;
if (!lws_adopt_descriptor_vhost(vhd->vhost, 0, u, "protocol-lws-raw-test", NULL)) {
lwsl_err("Failed to adopt fifo descriptor\n");
close(vhd->fifo);
return 1;
}
}
break;
case LWS_CALLBACK_RAW_WRITEABLE_FILE:
lwsl_notice("LWS_CALLBACK_RAW_WRITEABLE_FILE\n");
break;
/*
* Callbacks related to Raw socket descriptor testing
*/
case LWS_CALLBACK_RAW_ADOPT:
lwsl_notice("LWS_CALLBACK_RAW_ADOPT\n");
break;
case LWS_CALLBACK_RAW_RX:
lwsl_notice("LWS_CALLBACK_RAW_RX %ld\n", (long)len);
if (len > sizeof(pss->buf))
len = sizeof(pss->buf);
memcpy(pss->buf, in, len);
pss->len = len;
lws_callback_on_writable(wsi);
break;
case LWS_CALLBACK_RAW_CLOSE:
lwsl_notice("LWS_CALLBACK_RAW_CLOSE\n");
break;
case LWS_CALLBACK_RAW_WRITEABLE:
lwsl_notice("LWS_CALLBACK_RAW_WRITEABLE\n");
lws_write(wsi, pss->buf, pss->len, LWS_WRITE_HTTP);
break;
default:
break;
}
return 0;
}
#define LWS_PLUGIN_PROTOCOL_RAW_TEST \
{ \
"protocol-lws-raw-test", \
callback_raw_test, \
sizeof(struct per_session_data__raw_test), \
1024, /* rx buf size must be >= permessage-deflate rx size */ \
}
#if !defined (LWS_PLUGIN_STATIC)
static const struct lws_protocols protocols[] = {
LWS_PLUGIN_PROTOCOL_RAW_TEST
};
LWS_EXTERN LWS_VISIBLE int
init_protocol_lws_raw_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_EXTERN LWS_VISIBLE int
destroy_protocol_lws_raw_test(struct lws_context *context)
{
return 0;
}
#endif