Fix Websocket extended length

CMakeLists.txt

@@ -1,7 +1,9 @@
 cmake_minimum_required(VERSION 3.13)
 set(PROJECT webkeyboard)
 set(PICO_SDK_PATH /home/kenji/programming/pico/c/pico-sdk)
+if (NOT DEFINED PICO_BOARD)
 	set(PICO_BOARD pico_w)
+endif()
 include (${PICO_SDK_PATH}/external/pico_sdk_import.cmake)
 project(${PROJECT} C CXX ASM)
 
@@ -33,10 +35,12 @@ target_sources(${PROJECT} PRIVATE
 	usb_descriptors.c
 	parse_keys.c
 	dhcpserver.c
+	websocket.c
 )
 
 pico_enable_stdio_usb(${PROJECT} 1)
-pico_enable_stdio_uart(${PROJECT} 1)
+
+set_target_properties(${PROJECT} PROPERTIES OUTPUT_NAME "${PROJECT}-${PICO_BOARD}")
 
 pico_add_extra_outputs(${PROJECT})
 
@@ -47,6 +51,8 @@ target_link_libraries(${PROJECT}
 	pico_lwip_http
 	pico_stdlib
 	pico_multicore
+	pico_mbedtls
+	tinyusb_board
 	tinyusb_device
 )
 

README.md

@@ -2,28 +2,31 @@
 
 ## About
 
-This project turns a Raspberry Pi Pico W into a web-based USB HID keyboard 
+This project turns a Raspberry Pi Pico W or Raspberry Pi Pico 2 W into a
-device. Users can access a webpage served over HTTP to enter keyboard input
+web-based USB HID keyboard  device. Users can access a webpage served over HTTP
-onto the host device of the Raspberry Pi Pico W. Input keys can be entered
+to enter keyboard input onto the host device of the Raspberry Pi Pico (2) W.
-through a keyboard on the client device or by pressing on the keys on the
+Input keys can be entered through a keyboard on the client device or by
-graphical interface served on the webpage.
+pressing on the keys on the graphical interface served on the webpage.
 
 ![Web interface for Web Keyboard](web-ui.jpg)
 
 ## Setup
 
-Download the webkeyboard.uf2 file from the latest
+[Installation and demo video](https://youtu.be/uORnxt5DLTw)
-[release](https://git.kkozai.com/kenji/webkeyboard/releases) and flash
-onto the Raspberry Pi Pico W by holding down the BOOTSEL button while plugging
-into your computer so that it appears as a USB drive, then transfer the
-firmware file onto the Pico W. After unmounting, connect the Raspberry Pi Pico
-W with a micro USB cable to the host computer or other device.
 
-On initial boot, the Raspberry Pi Pico W will enter Access Point mode with
+Download the appropriate firmware file for your board, either
+webkeyboard-pico_w.uf2 or webkeyboard-pico2_w.uf2, from the latest
+[release](https://git.kkozai.com/kenji/webkeyboard/releases) and flash
+onto the Raspberry Pi Pico (2) W by holding down the BOOTSEL button while
+plugging into your computer so that it appears as a USB drive, then transfer the
+firmware file onto the Pico (2) W. After unmounting, connect the Raspberry Pi
+Pico (2) W with a micro USB cable to the host computer or other device.
+
+On initial boot, the Raspberry Pi Pico (2) W will enter Access Point mode with
 SSID "picokb" and password "password". Connect to this network with another
 device and open a browser window to http://192.168.0.1.
 Go to the "Configure W-Fi" page and enter the SSID and password to the
-network that you would like the Raspberry Pi Pico W to connect. Optionally,
+network that you would like the Raspberry Pi Pico (2) W to connect. Optionally,
 also enter a hostname for the device and static IP information. Hit the "Save"
 button to save the network information to device flash.
 

html/index.html

@@ -48,12 +48,6 @@ div.blank {
 	opacity: 0;
 }
 
-div.info div {
-	font-size: 1.5em;
-	display: inline-block;
-	margin: 1em;
-}
-
 div#macros div {
 	width: 9em;
 	display: inline-block;
@@ -89,8 +83,8 @@ div.menu a:hover {
 
 <script>
 var keys = [];
-var fetchqueue = [];
+var mouse = [];
-var curLed = 0;
+var sendMouseInterval = null;
 const indicator_list = [
 	{id: "num", label: "NumLock"},
 	{id: "caps", label: "CapsLock"},
@@ -102,7 +96,7 @@ const macro_list = [
 	{id: "close", label: "ALT+F4", keys: ["AltLeft", "F4"]},
 	{id: "cycle", label: "ALT+Tab", keys: ["AltLeft", "Tab"]}
 ];
-const key_list = [
+const keyboard_list = [
 	[
 		{id: "Escape", label: "ESC", width: 2},
 		{id: "F1", label: "F1"},
@@ -223,15 +217,40 @@ const key_list = [
 		{id: "NumpadDecimal", label: "Del<br>."}
 	],
 ];
+const mouse_list = [
+	[
+		{id: "", label: ""},
+		{id: "MouseUp", label: "<br>&uArr;", repeat: 1},
+		{id: "", label: ""}
+	],
+	[
+		{id: "MouseLeft", label: "<br>&lArr;", repeat: 1},
+		{id: "", label: ""},
+		{id: "MouseRight", label: "<br>&rArr;", repeat: 1}
+	],
+	[
+		{id: "", label: ""},
+		{id: "MouseDown", label: "<br>&dArr;", repeat: 1},
+		{id: "", label: ""}
+	],
+	[
+		{id: "MouseClickLeftt", label: "Left Click", width: 1.5},
+		{id: "MouseClickRight", label: "Right Click", width: 1.5}
+	],
+];
 
-window.setInterval("refreshIndicators();",2000);
+
+window.onload = (event) => {
+	createMacros("macros");
+	createKeys("keyboard", keyboard_list);
+	createKeys("mouse", mouse_list);
+	createIndicators("indicators");
 
 	window.addEventListener("keydown", onKeyDown, true);
 	window.addEventListener("keyup", onKeyUp, true);
 
-window.onload = (event) => {
+	socket = new WebSocket("ws://" + window.location.hostname + ":8080/");
-	createMacros("macros");
+	socket.onmessage = function (event) { updateLEDs(event.data); };
-	createKeys("keyboard");
 }
 
 function onKeyDown(event) {
@@ -245,14 +264,22 @@ function onKeyDown(event) {
 	event.preventDefault();
 }
 
-function pressKey(code) {
+function pressKey(code, repeat=false) {
+	if (code.indexOf("Mouse") >= 0) {
+		if (mouse.includes(code)) { return; }
+		mouse.push(code);
+		sendKeys(mouse, true);
+	} else{
 		if (keys.includes(code)) { return; }
-
 		keys.push(code);
-
 		sendKeys(keys);
 	}
 
+	if ( sendMouseInterval == null && repeat) {
+		sendMouseInterval = setInterval( function() { sendKeys(mouse, true); }, 50 );
+	}
+}
+
 function onKeyUp(event) {
 	if (event.defaultPrevented) {
 		return; // Do nothing if the event was already processed
@@ -264,21 +291,27 @@ function onKeyUp(event) {
 	event.preventDefault();
 }
 
-function releaseKey(code) {
+function releaseKey(code, repeat=false) {
+	if (code.indexOf("Mouse") >= 0) {
+		if (mouse.includes(code)) {
+			mouse.splice(mouse.indexOf(code),1);
+		}
+		sendKeys(mouse, true);
+	} else{ 
 		if (keys.includes(code)) {
 			keys.splice(keys.indexOf(code),1);
 		}
-
 		sendKeys(keys);
 	}
 
+	if (sendMouseInterval != null && repeat) {
+		clearInterval(sendMouseInterval);
+		sendMouseInterval = null;
+	}
+}
 
-function sendKeys(curKeys) {
+function sendKeys(curKeys, is_mouse) {
-	const url="sendkeys.cgi?keys=".concat(curKeys);
+	// update highlighting of pressed keys
-	fetchqueue.push(url);
-	console.log(fetchqueue);
-	document.getElementById("downKeys")
-		.innerHTML = curKeys;
 	prev_keys = document.getElementsByClassName("pressed");
 	for (let key of curKeys) {
 		keyDiv = document.getElementById(key);
@@ -289,33 +322,25 @@ function sendKeys(curKeys) {
 			key.classList.remove("pressed");
 		}
 	}
-	if (fetchqueue.length == 1) {
+
-		runQueue();
+	// send updated key or mouse status
+	if (socket.readyState == WebSocket.OPEN) {
+		if (is_mouse == true) {
+			socket.send("M: " + curKeys);
+		} else {
+			socket.send("K: " + curKeys);
+		}
+	} else if (socket.readyState == WebSocket.CLOSED) {
+		socket = new WebSocket("ws://" + window.location.hostname + ":8080/");
+		socket.onmessage = function (event) { updateLEDs(event.data); };
+		setTimeout( function () { sendKeys(curKeys, is_mouse); }, 10);
+	} else {
+		setTimeout( function () { sendKeys(curKeys, is_mouse); }, 10);
 	}
 }
 
-async function runQueue() {
+function createKeys(div_id, key_list) {
-	const url = fetchqueue[0];
+	let keyboardDiv = document.getElementById(div_id);
-	await fetch(url);
-	fetchqueue.shift();
-	if (fetchqueue.length > 0) {
-		runQueue();
-	}
-}
-
-function updateIndicators() {
-	let indicatorFrame = document.getElementById("indicatorFrame");
-	let indicatorDiv = document.getElementById("indicators");
-	indicatorDiv.innerHTML = indicatorFrame.contentDocument.body.innerHTML;
-}
-
-function refreshIndicators() {
-	let indicatorFrame = document.getElementById("indicatorFrame");
-	indicatorFrame.contentWindow.location.reload(true);
-}
-
-function createKeys(keyboard_id) {
-	let keyboardDiv = document.getElementById(keyboard_id);
 	for (let row of key_list) {
 		let newRow = document.createElement("div");
 		keyboardDiv.appendChild(newRow);
@@ -325,6 +350,16 @@ function createKeys(keyboard_id) {
 				newDiv.id = key.id;
 				newDiv.innerHTML = key.label;
 				newDiv.className = "key";
+				if (key.repeat) {
+					newDiv.addEventListener("touchstart", function (event) {
+						event.preventDefault(); pressKey(key.id, true); });
+					newDiv.addEventListener("touchend", function (event) {
+						event.preventDefault(); releaseKey(key.id, true); });
+					newDiv.addEventListener("mousedown", function () {
+						pressKey(key.id, true); });
+					newDiv.addEventListener("mouseup", function () {
+						releaseKey(key.id, true); });
+				} else {
 					newDiv.addEventListener("touchstart", function (event) {
 						event.preventDefault(); pressKey(key.id); });
 					newDiv.addEventListener("touchend", function (event) {
@@ -333,6 +368,7 @@ function createKeys(keyboard_id) {
 						pressKey(key.id); });
 					newDiv.addEventListener("mouseup", function () {
 						releaseKey(key.id); });
+				}
 			} else {
 				newDiv.className = "key blank";
 			}
@@ -365,6 +401,29 @@ function createMacros(macro_id) {
 	}
 }
 
+function createIndicators(indicator_id) {
+	let indicatorDiv = document.getElementById(indicator_id);
+	for (let indicator of indicator_list) {
+		let newDiv = document.createElement("div");
+		newDiv.id = indicator.id;
+		newDiv.textContent = indicator.label;
+		newDiv.className = "off";
+		indicatorDiv.appendChild(newDiv);
+	}
+}
+
+function updateLEDs(cur_state) {
+	let on_leds = cur_state.split(",");
+	for (let indicator of indicator_list) {
+		let indicator_div = document.getElementById(indicator.id);
+		if (on_leds.includes(indicator.id)) {
+			indicator_div.className = "on";
+		} else {
+			indicator_div.className = "off";
+		}
+	}
+}
+
 </script>
 
 </head>
@@ -372,16 +431,15 @@ function createMacros(macro_id) {
 <body>
 <div class="container">
 	<div id="keyboard"></div>
+	<div>
 		<div id="indicators"></div>
+		<div>Mouse Controls:</div>
+		<div id="mouse"></div>
+	</div>
 </div>
 
 <div id="macros"></div>
 
-<div class="info">
-	<div>Currently pressed keys:</div>
-	<div id="downKeys"></div>
-</div>
-
 <div>
 	<div class="menu">
 		<a href="wifi.shtml">Configure Wi-Fi</a>
@@ -391,11 +449,6 @@ function createMacros(macro_id) {
 	</div>
 </div>
 
-<div id="status_frames">
-	<iframe id="indicatorFrame" src="indicators.shtml"
-		onload="updateIndicators();"></iframe>
-</div>
-
 </body>
 
 </html>

html/indicators.shtml

@@ -1,15 +0,0 @@
-<!DOCTYPE html>
-
-<html>
-
-<head>
-<title>Keyboard Indicators</title>
-</head>
-
-<body>
-<div id="num" class="<!--#num-->">NumLock</div>
-<div id="caps" class="<!--#caps-->">CapsLock</div>
-<div id="scroll" class="<!--#scroll-->">ScrollLock</div>
-</body>
-
-</html>

html/wifi.shtml

@@ -55,7 +55,7 @@ window.onload = () => {
 <div><h1>Web Keyboard Wi-Fi Settings</h1></div>
 
 <div class="container">
-<form method="get" action="wifi.cgi">
+<form method="post" action="wifi.cgi">
 	<div><h2>Wi-Fi Network</h2></div>
 
 	<div class="field">

lwipopts.h

@@ -115,6 +115,7 @@
 #define LWIP_HTTPD_CGI				1
 #define LWIP_HTTPD_SSI				1
 #define LWIP_HTTPD_SSI_INCLUDE_TAG	0
+#define LWIP_HTTPD_SUPPORT_POST		1
 #define HTTPD_FSDATA_FILE			"my_fsdata.c"
 
 

mbedtls_config.h

@@ -0,0 +1,75 @@
+#ifndef MBEDTLS_CONFIG_H
+#define MBEDTLS_CONFIG_H
+
+/* Workaround for some mbedtls source files using INT_MAX without including limits.h */
+#include <limits.h>
+
+#define MBEDTLS_NO_PLATFORM_ENTROPY
+#define MBEDTLS_ENTROPY_HARDWARE_ALT
+
+#define MBEDTLS_SSL_OUT_CONTENT_LEN    2048
+
+#define MBEDTLS_ALLOW_PRIVATE_ACCESS
+#define MBEDTLS_HAVE_TIME
+#define MBEDTLS_PLATFORM_MS_TIME_ALT
+
+#define MBEDTLS_CIPHER_MODE_CBC
+#define MBEDTLS_ECP_DP_SECP192R1_ENABLED
+#define MBEDTLS_ECP_DP_SECP224R1_ENABLED
+#define MBEDTLS_ECP_DP_SECP256R1_ENABLED
+#define MBEDTLS_ECP_DP_SECP384R1_ENABLED
+#define MBEDTLS_ECP_DP_SECP521R1_ENABLED
+#define MBEDTLS_ECP_DP_SECP192K1_ENABLED
+#define MBEDTLS_ECP_DP_SECP224K1_ENABLED
+#define MBEDTLS_ECP_DP_SECP256K1_ENABLED
+#define MBEDTLS_ECP_DP_BP256R1_ENABLED
+#define MBEDTLS_ECP_DP_BP384R1_ENABLED
+#define MBEDTLS_ECP_DP_BP512R1_ENABLED
+#define MBEDTLS_ECP_DP_CURVE25519_ENABLED
+#define MBEDTLS_KEY_EXCHANGE_RSA_ENABLED
+#define MBEDTLS_PKCS1_V15
+#define MBEDTLS_SHA256_SMALLER
+#define MBEDTLS_SSL_SERVER_NAME_INDICATION
+#define MBEDTLS_AES_C
+#define MBEDTLS_ASN1_PARSE_C
+#define MBEDTLS_BIGNUM_C
+#define MBEDTLS_CIPHER_C
+#define MBEDTLS_CTR_DRBG_C
+#define MBEDTLS_ENTROPY_C
+#define MBEDTLS_ERROR_C
+#define MBEDTLS_MD_C
+#define MBEDTLS_MD5_C
+#define MBEDTLS_OID_C
+#define MBEDTLS_PKCS5_C
+#define MBEDTLS_PK_C
+#define MBEDTLS_PK_PARSE_C
+#define MBEDTLS_PLATFORM_C
+#define MBEDTLS_RSA_C
+#define MBEDTLS_SHA1_C
+#define MBEDTLS_SHA224_C
+#define MBEDTLS_SHA256_C
+#define MBEDTLS_SHA512_C
+#define MBEDTLS_SSL_CLI_C
+#define MBEDTLS_SSL_SRV_C
+#define MBEDTLS_SSL_TLS_C
+#define MBEDTLS_X509_CRT_PARSE_C
+#define MBEDTLS_X509_USE_C
+#define MBEDTLS_AES_FEWER_TABLES
+
+/* TLS 1.2 */
+#define MBEDTLS_SSL_PROTO_TLS1_2
+#define MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED
+#define MBEDTLS_GCM_C
+#define MBEDTLS_ECDH_C
+#define MBEDTLS_ECP_C
+#define MBEDTLS_ECDSA_C
+#define MBEDTLS_ASN1_WRITE_C
+
+// The following is needed to parse a certificate
+#define MBEDTLS_PEM_PARSE_C
+#define MBEDTLS_BASE64_C
+
+// The following significantly speeds up mbedtls due to NIST optimizations.
+#define MBEDTLS_ECP_NIST_OPTIM
+
+#endif

parse_keys.c

@@ -7,6 +7,8 @@
 #include "parse_keys.h"
 #include "usb_descriptors.h"
 
+static unsigned char boot_buf[8];
+
 // take a list of Javascript keys representing pressed keys and turn into
 // a 8 byte USB boot keyboard report format
 void parse_key_list(char * keys) {
@@ -28,9 +30,9 @@ void parse_key_list(char * keys) {
 		}
 
 		// if a scan code was not returned, it might be a modifier
+		if (code == 0x00) {
 			// search for the correct modifier bit and add it to byte 0 of the
 			// USB boot keyboard report
-		if (code == 0x00) {
 			code = parse_mod(token);
 			if (code) {
 				boot_report[0] = boot_report[0] | code;
@@ -40,7 +42,7 @@ void parse_key_list(char * keys) {
 	}
 
 	// print resulting HID boot keyboard report to CDC for debugging
-	printf("HID report: ");
+	printf("Keyboard report: ");
 	for(int i=0; i<8; i++){
 		printf("%02X ",boot_report[i]);
 	}
@@ -49,6 +51,38 @@ void parse_key_list(char * keys) {
 	tud_hid_report(REPORT_ID_KEYBOARD, boot_report, 8);
 }
 
+void parse_mouse_list (char * keys) {
+	static unsigned char mouse_report[5];
+	memset(mouse_report, 0x00, 5);
+
+	// Javascript sends the list as comma delimited, so split into individual
+	// keys by splitting at commas
+	char * token = strtok(keys, ",");
+	while (token != NULL) {
+		if ( strncmp(&token[0],"MouseLeft", 9) == 0 ){
+			mouse_report[1] = -1*MOUSE_SPEED;
+		} else if ( strncmp(&token[0], "MouseRight", 10) == 0 ) {
+			mouse_report[1] = 1*MOUSE_SPEED;
+		} else if ( strncmp(&token[0], "MouseUp", 7) == 0 ) {
+			mouse_report[2] = -1*MOUSE_SPEED;
+		} else if ( strncmp(&token[0], "MouseDown", 9) == 0 ) {
+			mouse_report[2] = 1*MOUSE_SPEED;
+		} else if ( strncmp(&token[0], "MouseClickLeft", 14) == 0 ) {
+			mouse_report[0] = mouse_report[0] | 1;
+		} else if ( strncmp(&token[0], "MouseClickRight", 15) == 0) {
+			mouse_report[0] = mouse_report[0] | 2;
+		}
+		token = strtok(NULL, ",");
+	}
+
+	// print resulting HID boot mouse report to CDC for debugging
+	printf("Mouse report: ");
+	for(int i=0; i<5; i++){
+		printf("%02X ",mouse_report[i]);
+	}
+	printf("\n");
+	tud_hid_report(REPORT_ID_MOUSE, mouse_report, 5);
+}
 
 // take a single Javascript key code and convert it to USB HID scancode
 // if it is a regular key, i.e. not a modifier key
@@ -75,4 +109,3 @@ uint8_t parse_mod(char * key) {
 	}
 	return 0x00;
 }
-

parse_keys.h

@@ -1,15 +1,16 @@
 #ifndef PARSE_KEYS_H_
 #define PRASE_KEYS_H_
 
-static unsigned char boot_buf[8];
+#define MOUSE_SPEED 10
+
 
 void parse_key_list(char * keys);
+void parse_mouse_list(char * keys);
 uint8_t parse_key_single(char * key);
 uint8_t parse_mod(char * key);
 
 typedef struct { char * key; uint8_t val; } keycode_dict;
 
-
 // modifier key bit codes
 #define KEY_MOD_LCTRL  0x01
 #define KEY_MOD_LSHIFT 0x02

server.c

@@ -10,9 +10,11 @@
 #include "hardware/sync.h"
 #include "pico/multicore.h"
 
-#include "server.h"
 #include "parse_keys.h"
 #include "dhcpserver.h"
+#include "websocket.h"
+
+#include "server.h"
 
 uint8_t led_code = 0;
 static uint8_t ip[4];
@@ -25,12 +27,10 @@ static bool clientmode = false;
 static bool config_loaded = false;
 static bool bad_config = false;
 static bool reboot = false;
+static void *current_connection;
 
 // list of SSI variable names for lwIP SSI handler
 const char * __not_in_flash("httpd") ssi_tags[] = {
-	"num",
-	"caps",
-	"scroll",
 	"ssid",
 	"pass",
 	"host",
@@ -49,10 +49,23 @@ const char * __not_in_flash("httpd") ssi_tags[] = {
 	"dhcp"
 };
 
+const char * ip_parts[] = {
+	"ip0=",
+	"ip1=",
+	"ip2=",
+	"ip3=",
+	"mask0=",
+	"mask1=",
+	"mask2=",
+	"mask3=",
+	"gw0=",
+	"gw1=",
+	"gw2=",
+	"gw3="
+};
+#define NPARTS ( sizeof( ip_parts )/ sizeof(ip_parts[0]) )
 
 static const tCGI cgi_handlers[] = {
-	{ "/sendkeys.cgi", sendkeys_cgi },
-	{ "/wifi.cgi", save_wifi },
 	{ "/reboot.cgi", reboot_cgi },
 };
 
@@ -119,7 +132,7 @@ void run_http_server() {
 
 	// start the HTTP web server for keyboard input and config page
 	httpd_init();
-	http_set_cgi_handlers(cgi_handlers, 3);
+	http_set_cgi_handlers(cgi_handlers, 1);
 	for (size_t i = 0; i < LWIP_ARRAYSIZE(ssi_tags); i++) {
 	LWIP_ASSERT("tag too long for LWIP_HTTPD_MAX_TAG_NAME_LEN",
 		strlen(ssi_tags[i]) <= LWIP_HTTPD_MAX_TAG_NAME_LEN);
@@ -127,6 +140,12 @@ void run_http_server() {
 	http_set_ssi_handler(ssi_handler, ssi_tags, LWIP_ARRAYSIZE(ssi_tags));
 	printf("HTTP server initialized\n");
 
+	// start the websocket server
+	ws_server_init();
+	ws_set_open_handler(ws_open_handler);
+	ws_set_receive_handler(ws_receive_handler);
+	printf("Websocket server initialized\n");
+
 	// start a watchdog timer with 8 seconds so it can reboot if it disconnects
 	watchdog_enable(8000,1);
 
@@ -169,104 +188,6 @@ void run_http_server() {
 	}
 }
 
-// lwIP cgi handler for GET requests to sendkeys.cgi
-const char * sendkeys_cgi (int iIndex, int iNumParams, char *pcParam[], char *pcValue[]) {
-	for (int i=0; i < iNumParams; i++) {
-		// search GET parameters for keys and forward for processing to USB
-		if (strcmp(pcParam[i], "keys") == 0 ) {
-			parse_key_list(pcValue[i]);
-		}
-	}
-
-	lastActive= get_absolute_time();
-
-	// send return page
-	return "/success.html";
-}
-
-// lwIP cgi handler for form submission of network config to wifi.cgi
-const char * save_wifi (int iIndex, int iNumParams, char *pcParam[], char *pcValue[]) {
-	// clear all values in manual network settings
-	memset(ip, 0, sizeof(ip));
-	memset(mask, 0, sizeof(mask));
-	memset(gw, 0, sizeof(gw));
-
-	bad_config = false;
-	wifi.manual = true;
-
-	// read parameter values
-	for (int i=0; i < iNumParams; i++) {
-		if (strcmp(pcParam[i], "ssid") == 0){
-			if (pcValue[i][0] == "\0") {
-				bad_config = true;
-			} else {
-				urldecode(pcValue[i], wifi.ssid);
-			}
-		} else if (strcmp(pcParam[i], "pass") == 0) {
-			urldecode(pcValue[i], wifi.pass);
-		} else if (strcmp(pcParam[i], "host") == 0) {
-			urldecode(pcValue[i], wifi.host);
-		} else if (strcmp(pcParam[i], "dhcp") == 0) {
-			wifi.manual = false;
-		} else if (strncmp(pcParam[i], "ip", 2) ==0 ) {
-			uint8_t part = atoi(&(pcParam[i][2]));
-			int val = atoi(pcValue[i]);
-			if (pcValue[i][0] == "\0" || val > 255 || val < 0 || part > 4) {
-				bad_config = true;
-			} else {
-				ip[part] = (uint8_t) val;
-			}
-		} else if (strncmp(pcParam[i], "gw", 2) ==0 ) {
-			uint8_t part = atoi(&(pcParam[i][2]));
-			int val = atoi(pcValue[i]);
-			if (pcValue[i][0] == "\0" || val > 255 || val < 0 || part > 4) {
-				bad_config = true;
-			} else {
-				gw[part] = (uint8_t) val;
-			}
-		} else if (strncmp(pcParam[i], "mask", 4) ==0 ) {
-			uint8_t part = atoi(&(pcParam[i][4]));
-			int val = atoi(pcValue[i]);
-			if (pcValue[i][0] == "\0" || val > 255 || val < 0 || part > 4) {
-				bad_config = true;
-			} else {
-				mask[part] = (uint8_t) val;
-			}
-		}
-	}
-
-	if (bad_config) {
-		// config is invalid, so don't save and return to config page
-		return "/wifi.shtml";
-	} else {
-		// config is valid, prepare for saving to flash
-		IP4_ADDR(&(wifi.ip), ip[0], ip[1], ip[2], ip[3]);
-		if(!wifi.ip.addr) {
-			wifi.ip.addr = IPADDR_NONE;
-		}
-		IP4_ADDR(&(wifi.mask), mask[0], mask[1], mask[2], mask[3]);
-		if(!wifi.mask.addr) {
-			wifi.mask.addr = IPADDR_NONE;
-		}
-		IP4_ADDR(&(wifi.gw), gw[0], gw[1], gw[2], gw[3]);
-		if(!wifi.gw.addr) {
-			wifi.gw.addr = IPADDR_NONE;
-		}
-		wifi.header = STARTFILE;
-		wifi.footer = ENDFILE;
-		config_loaded = true;
-
-		watchdog_update();
-
-		// save configuratitons to flash
-		net_config_write(&wifi);
-
-		printf("wifi settings saved\n");
-
-		return "/success.html";
-	}
-}
-
 // lwIP cgi handler for reboots initiated from the web
 const char * reboot_cgi(int iIndex, int iNumParams, char *pcParam[], char *pcValue[]) {
 	// turn on reboot flag to prevent watchdog from updating
@@ -275,7 +196,7 @@ const char * reboot_cgi(int iIndex, int iNumParams, char *pcParam[], char *pcVal
 	return "/success.html";
 }
 
-
+// write configuration data to flash memory
 void net_config_write(net_config *config) {
 	// core 0 must have its TinyUSB interrupts disabled to allow flash writes
 	multicore_lockout_start_blocking();
@@ -310,79 +231,58 @@ bool net_config_load(net_config *config) {
 uint16_t __time_critical_func(ssi_handler)(int iIndex, char *pcInsert, int iInsertLen) {
 	size_t printed;
 	switch (iIndex) {
-		case 0: //num - numlock status
+		case 0: //ssid - network config SSID
-			if (led_code & 1) {
-				printed = snprintf(pcInsert, iInsertLen, "on");
-			} else {
-				printed = snprintf(pcInsert, iInsertLen, "off");
-			}
-			break;
-		case 1: //caps - capslock status
-			if (led_code & 2) {
-				printed = snprintf(pcInsert, iInsertLen, "on");
-			} else {
-				printed = snprintf(pcInsert, iInsertLen, "off");
-			}
-			break;
-		case 2: //scroll - scrollock status
-			if (led_code & 4) {
-				printed = snprintf(pcInsert, iInsertLen, "on");
-			} else {
-				printed = snprintf(pcInsert, iInsertLen, "off");
-			}
-			break;
-		case 3: //ssid - network config SSID
 			if (config_loaded && wifi.ssid) {
 				printed = snprintf(pcInsert, iInsertLen, "value=\"%s\"", wifi.ssid);
 			} else {
 				printed = 0;
 			}
 			break;
-		case 4: //pass - network config password
+		case 1: //pass - network config password
 			if (config_loaded && wifi.pass) {
 				printed = snprintf(pcInsert, iInsertLen, "value=\"%s\"", wifi.pass);
 			} else {
 				printed = 0;
 			}
 			break;
-		case 5: //host - network config hostname
+		case 2: //host - network config hostname
 			if (config_loaded && wifi.host) {
 				printed = snprintf(pcInsert, iInsertLen, "value=\"%s\"", wifi.host);
 			} else {
 				printed = 0;
 			}
 			break;
-		case 6:
+		case 3:
+		case 4:
+		case 5:
+		case 6: //ip0-3 - network config manual IP address parts
+			if (config_loaded && wifi.ip.addr) {
+				printed = snprintf(pcInsert, iInsertLen, "value=\"%d\"", ip4_addr_get_byte(&(wifi.ip), iIndex-3));
+			} else {
+				printed = 0;
+			}
+			break;
 		case 7:
 		case 8:
-		case 9: //ip0-3 - network config manual IP address parts
+		case 9:
-			if (config_loaded && wifi.ip.addr) {
+		case 10: //mask0-3 - network config manual netmask parts
-				printed = snprintf(pcInsert, iInsertLen, "value=\"%d\"", ip4_addr_get_byte(&(wifi.ip), iIndex-6));
+			if (config_loaded && wifi.mask.addr) {
+				printed = snprintf(pcInsert, iInsertLen, "value=\"%d\"", ip4_addr_get_byte(&(wifi.mask), iIndex-7));
 			} else {
 				printed = 0;
 			}
 			break;
-		case 10:
 		case 11:
 		case 12:
-		case 13: //mask0-3 - network config manual netmask parts
+		case 13:
-			if (config_loaded && wifi.mask.addr) {
+		case 14: //gw0-3 - network config manual gateway parts
-				printed = snprintf(pcInsert, iInsertLen, "value=\"%d\"", ip4_addr_get_byte(&(wifi.mask), iIndex-10));
-			} else {
-				printed = 0;
-			}
-			break;
-		case 14:
-		case 15:
-		case 16:
-		case 17: //gw0-3 - network config manual gateway parts
 			if (config_loaded && wifi.gw.addr) {
-				printed = snprintf(pcInsert, iInsertLen, "value=\"%d\"", ip4_addr_get_byte(&(wifi.gw), iIndex-14));
+				printed = snprintf(pcInsert, iInsertLen, "value=\"%d\"", ip4_addr_get_byte(&(wifi.gw), iIndex-11));
 			} else {
 				printed = 0;
 			}
 			break;
-		case 18: // dhcp - network config DHCP client enabled/disabled
+		case 15: // dhcp - network config DHCP client enabled/disabled
 			if ((!config_loaded) || !(wifi.manual) ){
 				printed = snprintf(pcInsert, iInsertLen, "checked");
 			} else {
@@ -397,12 +297,190 @@ uint16_t __time_critical_func(ssi_handler)(int iIndex, char *pcInsert, int iInse
 	return (uint16_t)printed;
 }
 
+// lwIP handler for POST requests
+err_t httpd_post_begin(void *connection, const char *uri,
+	const char * http_request, u16_t http_request_len, int content_len,
+	char *response_uri,u16_t response_uri_len, u8_t *post_auto_wnd) {
+	if (memcmp(uri, "/wifi.cgi", 9) == 0 && current_connection != connection) {
+		// initiate post request to wifi.cgi
+		current_connection = connection;
+		// default page is wifi config page 
+		snprintf(response_uri, response_uri_len, "/wifi.shtml");
+		*post_auto_wnd = 1;
+		return ERR_OK;
+	}
+	return ERR_VAL;
+}
+
+// lwIP handler for receiving POST data
+err_t httpd_post_receive_data(void *connection, struct pbuf *p) {
+	if (current_connection == connection) {
+		// clear all values in manual network settings
+		memset(ip, 0, sizeof(ip));
+		memset(mask, 0, sizeof(mask));
+		memset(gw, 0, sizeof(gw));
+
+		bad_config = false;
+		wifi.manual = true;
+		char buf[MAX_POST_PARAM_LEN];
+		char * value;
+
+		// read parameter values
+		value = find_post_param(p, "ssid=", buf, sizeof(buf));
+		if (value) {
+			urldecode(value, wifi.ssid);
+		} else {
+			bad_config = true;
+		}
+		value = find_post_param(p, "pass=", buf, sizeof(buf));
+		if (value) {
+			urldecode(value, wifi.pass);
+		} else {
+			wifi.pass[0]=0;
+		}
+		value = find_post_param(p, "host=", buf, sizeof(buf));
+		if (value) {
+			urldecode(value, wifi.host);
+		} else {
+			wifi.host[0]=0;
+		}
+		value = find_post_param(p, "dhcp=", buf, sizeof(buf));
+		if (value) {
+			wifi.manual = false;
+		} else {
+			for (int i=0; i< NPARTS; i++) {
+				value = find_post_param(p, ip_parts[i], buf, sizeof(buf));
+				if (value) {
+					int ip_part = atoi(value);
+					if (ip_part > 255 || ip_part < 0) {
+						bad_config = true;
+					} else {
+						if (strncmp(ip_parts[i], "ip", 2) == 0) {
+							uint8_t part = atoi(&ip_parts[i][2]);
+							ip[part] = (uint8_t) ip_part;
+						} else if (strncmp(ip_parts[i], "gw", 2) == 0) {
+							uint8_t part = atoi(&ip_parts[i][2]);
+							gw[part] = (uint8_t) ip_part;
+						} else if (strncmp(ip_parts[i], "mask", 4) == 0) {
+							uint8_t part = atoi(&ip_parts[i][4]);
+							mask[part] = (uint8_t) ip_part;
+						}
+					}
+				} else {
+					bad_config = true;
+				}
+			}
+		}
+
+		if (!bad_config) {
+			// config is valid, prepare for saving to flash
+			IP4_ADDR(&(wifi.ip), ip[0], ip[1], ip[2], ip[3]);
+			if(!wifi.ip.addr) {
+				wifi.ip.addr = IPADDR_NONE;
+			}
+			IP4_ADDR(&(wifi.mask), mask[0], mask[1], mask[2], mask[3]);
+			if(!wifi.mask.addr) {
+				wifi.mask.addr = IPADDR_NONE;
+			}
+			IP4_ADDR(&(wifi.gw), gw[0], gw[1], gw[2], gw[3]);
+			if(!wifi.gw.addr) {
+				wifi.gw.addr = IPADDR_NONE;
+			}
+			wifi.header = STARTFILE;
+			wifi.footer = ENDFILE;
+			config_loaded = true;
+
+			watchdog_update();
+
+			// save configurations to flash
+			net_config_write(&wifi);
+			printf("wifi settings saved\n");
+	
+			pbuf_free(p);
+			return ERR_OK;
+		}
+	}
+
+	pbuf_free(p);
+	current_connection = NULL;
+	return ERR_VAL;
+}
+
+// lwIP handler for end of POST request
+void httpd_post_finished(void *connection, char *response_uri, u16_t response_uri_len) {
+	// return to Wi-Fi config page unless save was successful
+	snprintf(response_uri, response_uri_len, "/wifi.shtml");
+	if (current_connection == connection) {
+		snprintf(response_uri, response_uri_len, "/success.html");
+	}
+	current_connection = NULL;
+}
+
+// return a value for a parameter from POST
+char *find_post_param(struct pbuf *p, const char *param, char *buf, size_t len) {
+	size_t param_len = strlen(param);
+	uint16_t param_pos = pbuf_memfind(p, param, param_len, 0);
+	if (param_pos != 0xFFFF) {
+		uint16_t value_pos = param_pos + param_len;
+		uint16_t value_len = 0;
+		uint16_t tmp;
+		
+		tmp = pbuf_memfind(p, "&", 1, value_pos);
+		if (tmp != 0xFFFF) {
+			value_len = tmp - value_pos;
+		} else {
+			value_len = p->tot_len - value_pos;
+		}
+		if (value_len > 0 && value_len < len) {
+			char *value = (char *) pbuf_get_contiguous(p, buf, len, value_len, value_pos);
+			if (value) {
+				value[value_len]=0;
+				return value;
+			}
+		}
+	}
+	return NULL;
+}
+
+const void ws_open_handler(struct ws_state * wss) {
+	send_indicators();
+}
+
+// handler for data received on websocket connection
+const void ws_receive_handler(uint8_t *data, uint16_t len) {
+	if (strncmp(data, "K: ", 3)==0) {
+		parse_key_list(&data[3]);
+	} else if (strncmp(data, "M: ", 3) == 0) {
+		parse_mouse_list(&data[3]);
+	}
+	
+	lastActive= get_absolute_time();
+}
+
 // save keyboard's LED indicator status to memory
 void set_indicator(uint8_t const* buffer) {
 	led_code = *buffer;
+
+	send_indicators();
 }
 
-// turn URL-formatted string from GET request and turn into regular string
+// read individual bits for indicator LED status and send over websocket to client
+void send_indicators(void){
+	char buf[16]="";
+	if (led_code & 1) {
+		strcat(buf, "num,");
+	}
+	if (led_code & 2) {
+		strcat(buf, "caps,");
+	}
+	if (led_code & 4) {
+		strcat(buf, "scroll");
+	}
+
+	ws_send_all(buf, strlen(buf));
+}
+
+// take URL-formatted string from GET request and turn into regular string
 void urldecode(char *urlstring, char *decoded) {
 	uint8_t conv;
 	while(*urlstring) {

server.h

@@ -2,11 +2,13 @@
 #define SERVER_H_
 
 #include "lwip/ip4_addr.h"
+#include "lwip/pbuf.h"
 
 #define STARTFILE	0x7fc6
 #define ENDFILE		0x0464
 #define DEFAULTHOST	"picokb"
 #define DEFAULTPASS	"password"
+#define MAX_POST_PARAM_LEN	63+1
 
 typedef struct  {
 	uint16_t header;
@@ -21,14 +23,16 @@ typedef struct  {
 } net_config;
 
 void run_http_server();
-const char * sendkeys_cgi(int iIndex, int iNumParams, char *pcParam[], char *pcValue[]);
-const char * save_wifi(int iIndex, int iNumParams, char *pcParam[], char *pcValue[]);
 const char * reboot_cgi(int iIndex, int iNumParams, char *pcParam[], char *pcValue[]);
 uint16_t __time_critical_func(ssi_handler)(int iIndex, char *pcInsert, int iInsertLen);
 void set_indicator(uint8_t const* buffer);
+void send_indicators(void);
 void urldecode(char *urlstring, char *dest);
 bool net_config_load(net_config *wifi);
 void net_config_write(net_config *wifi);
+char *find_post_param(struct pbuf *p, const char *param, char *buf, size_t len);
+const void ws_receive_handler(uint8_t *data, uint16_t len);
+const void ws_open_handler(struct ws_state * wss);
 
 #define FLASH_TARGET_OFFSET ((PICO_FLASH_SIZE_BYTES) - FLASH_SECTOR_SIZE)
 

usb_descriptors.c

@@ -25,20 +25,10 @@
  */
 
 #include "tusb.h"
+#include "bsp/board_api.h"
+
 #include "usb_descriptors.h"
 
-/* A combination of interfaces must have a unique product id, since PC will save device driver after the first plug.
- * Same VID/PID with different interface e.g MSC (first), then CDC (later) will possibly cause system error on PC.
- *
- * Auto ProductID layout's Bitmap:
- *   [MSB]         HID | MSC | CDC          [LSB]
- */
-#define _PID_MAP(itf, n)  ( (CFG_TUD_##itf) << (n) )
-#define USB_PID           (0x4000 | _PID_MAP(CDC, 0) | _PID_MAP(MSC, 1) | _PID_MAP(HID, 2) | \
-                           _PID_MAP(MIDI, 3) | _PID_MAP(VENDOR, 4) )
-
-#define USB_VID   0xCafe
-#define USB_BCD   0x0200
 
 //--------------------------------------------------------------------+
 // Device Descriptors
@@ -80,16 +70,10 @@ uint8_t const * tud_descriptor_device_cb(void)
 // Configuration Descriptor
 //--------------------------------------------------------------------+
 
-#define EPNUM_CDC_NOTIF	0x81
-#define EPNUM_CDC_OUT	0x02
-#define EPNUM_CDC_IN	0x82
-#define EPNUM_HID		0x83
-
-#define CONFIG_TOTAL_LEN    (TUD_CONFIG_DESC_LEN + TUD_CDC_DESC_LEN + TUD_HID_DESC_LEN)
-
 uint8_t const desc_hid_report[] =
 {
-  TUD_HID_REPORT_DESC_KEYBOARD( HID_REPORT_ID(REPORT_ID_KEYBOARD))
+	TUD_HID_REPORT_DESC_KEYBOARD( HID_REPORT_ID(REPORT_ID_KEYBOARD)),
+	TUD_HID_REPORT_DESC_MOUSE( HID_REPORT_ID(REPORT_ID_MOUSE))
 };
 
 
@@ -102,7 +86,7 @@ uint8_t const desc_fs_configuration[] =
 
 	// Interface number, string index, protocol, report descriptor len, EP In address, size & polling interval
 	TUD_CDC_DESCRIPTOR(ITF_NUM_CDC, 4, EPNUM_CDC_NOTIF, 8, EPNUM_CDC_OUT, EPNUM_CDC_IN, 64),
-	TUD_HID_DESCRIPTOR(ITF_NUM_HID, 5, HID_ITF_PROTOCOL_NONE, sizeof(desc_hid_report), EPNUM_HID, CFG_TUD_HID_EP_BUFSIZE, 5),
+	TUD_HID_DESCRIPTOR(ITF_NUM_HID, 5, HID_ITF_PROTOCOL_NONE, sizeof(desc_hid_report), EPNUM_HID, CFG_TUD_HID_EP_BUFSIZE, 8),
 };
 
 // Invoked when received GET CONFIGURATION DESCRIPTOR
@@ -125,12 +109,12 @@ char const* string_desc_arr [] =
 	(const char[]) { 0x09, 0x04 },	// 0: is supported language is English (0x0409)
 	"Raspberry Pi",					// 1: Manufacturer
 	"Pico Web Keyboard",			// 2: Product
-  "1234567890123456789",         // 3: Serials, should use chip ID
+	NULL,					        // 3: Serials, should use chip ID
-  "Pico Web Keyboard CDC",       // 4: CDC Interface
+	"Pico Web Keyboard CDC",		// 4: CDC
-  "TinyUSB Keyboard",            // 5: HID Keyboard Interface
+	"Pico Web Keyboard HID",		// 5: HID
 };
 
-static uint16_t _desc_str[32];
+static uint16_t _desc_str[32+1];
 
 // Invoked when received GET STRING DESCRIPTOR request
 // Application return pointer to descriptor, whose contents must exist long enough for transfer to complete
@@ -140,28 +124,31 @@ uint16_t const* tud_descriptor_string_cb(uint8_t index, uint16_t langid)
 
 	uint8_t chr_count;
 
-  if ( index == 0)
+	switch (index) {
-  {
+		case 0: // langid
 			memcpy(&_desc_str[1], string_desc_arr[0], 2);
 			chr_count = 1;
-  }else
+			break;
-  {
+		case 3: // serial
+			chr_count = board_usb_get_serial(_desc_str+1, 32);	
+			break;
+		default:
 			// Note: the 0xEE index string is a Microsoft OS 1.0 Descriptors.
 			// https://docs.microsoft.com/en-us/windows-hardware/drivers/usbcon/microsoft-defined-usb-descriptors
 
 			if ( !(index < sizeof(string_desc_arr)/sizeof(string_desc_arr[0])) ) return NULL;
 
-    const char* str = string_desc_arr[index];
+			char* str = string_desc_arr[index];
 
 			// Cap at max char
 			chr_count = (uint8_t) strlen(str);
 			if ( chr_count > 31 ) chr_count = 31;
 
 			// Convert ASCII string into UTF-16
-    for(uint8_t i=0; i<chr_count; i++)
+			for(uint8_t i=0; i<chr_count; i++) {
-    {
 				_desc_str[1+i] = str[i];
 			}
+			break;
 	}
 
 	// first byte is length (including header), second byte is string type
@@ -170,7 +157,6 @@ uint16_t const* tud_descriptor_string_cb(uint8_t index, uint16_t langid)
 	return _desc_str;
 }
 
-
 //--------------------------------------------------------------------+
 // Device HID
 //--------------------------------------------------------------------+

usb_descriptors.h

@@ -29,6 +29,7 @@ enum
 {
 	REPORT_ID_KEYBOARD = 1,
 	REPORT_ID_CONSUMER_CONTROL,
+	REPORT_ID_MOUSE,
 	REPORT_ID_COUNT
 };
 
@@ -40,5 +41,15 @@ enum
 	ITF_NUM_TOTAL
 };
 
+#define USB_PID		0x0EBD
+#define USB_VID		0xCEC0
+#define USB_BCD		0x0200
+
+#define EPNUM_CDC_NOTIF	0x81
+#define EPNUM_CDC_OUT	0x02
+#define EPNUM_CDC_IN	0x82
+#define EPNUM_HID		0x83
+
+#define CONFIG_TOTAL_LEN    (TUD_CONFIG_DESC_LEN + TUD_CDC_DESC_LEN + TUD_HID_DESC_LEN)
 
 #endif /* USB_DESCRIPTORS_H_ */

websocket.c

@@ -0,0 +1,471 @@
+#include <string.h>
+
+#include "lwip/altcp.h"
+#include "lwip/debug.h"
+#include "mbedtls/base64.h"
+#include "mbedtls/sha1.h"
+
+#include "websocket.h"
+
+static const char WS_GUID[] = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
+static const char WS_RESPONSE[] = "HTTP/1.1 101 Switching Protocols\r\n" \
+	"Upgrade: websocket\r\n" \
+	"Connection: Upgrade\r\n" \
+	"Sec-WebSocket-Accept: ";
+
+static uint8_t buf[WS_BUFFER_SIZE];
+static uint16_t buf_len=0;
+
+static tWSHandler ws_receive_cb = NULL;
+static tWSOpenHandler ws_open_cb = NULL;
+
+static struct ws_state * ws_connections;
+static uint8_t ws_num_conns = 0;
+
+static struct ws_state* ws_state_alloc(void);
+static void ws_state_init(struct ws_state *wss);
+static void ws_state_free(struct ws_state *wss);
+static void ws_server_init_pcb( struct altcp_pcb *pcb, uint16_t port);
+static err_t ws_accept(void *arg, struct altcp_pcb *pcb, err_t err);
+static err_t ws_recv(void *arg, struct altcp_pcb *pcb, struct pbuf *p, err_t err);
+static err_t ws_sent(void *arg, struct altcp_pcb *pcb, uint16_t len);
+static void ws_err (void *arg, err_t err);
+static err_t ws_close_conn(struct altcp_pcb *pcb, struct ws_state *wss);
+static err_t ws_close_or_abort_conn(struct altcp_pcb *pcb, struct ws_state *wss, uint8_t abort_conn);
+static err_t ws_poll(void *arg, struct altcp_pcb *pcb);
+static err_t ws_handshake(struct altcp_pcb *pcb, struct ws_state *wss, struct pbuf *p);
+static err_t ws_read(struct altcp_pcb *pcb, struct ws_state *wss, struct pbuf *p);
+static err_t ws_send(struct ws_state *wss, uint8_t *data, uint16_t len);
+
+// allocate memory for ws_state instance
+static struct ws_state * ws_state_alloc(void) {
+	struct ws_state *ret =  WS_ALLOC_WS_STATE();
+	
+	if ( ret != NULL) {
+		ws_state_init(ret);
+		if (ws_connections == NULL) {
+			ws_connections = ret;
+		} else {
+			struct ws_state *last;
+			for (last=ws_connections; last->next != NULL; last=last->next);
+			LWIP_ASSERT("last != NULL", last != NULL);
+			last->next = ret;
+		}
+	}
+
+	return ret;
+}
+
+// initiate ws_state instance
+static void ws_state_init(struct ws_state *wss) {
+	memset(wss, 0, sizeof(struct ws_state));
+	wss->active = false;
+}
+
+// free memory from ws_state instance
+static void ws_state_free(struct ws_state *wss) {
+	if (wss != NULL) {
+		if (ws_connections == wss) {
+			ws_connections = wss->next;
+		} else {
+			struct ws_state * last;
+			for (last = ws_connections; last->next != NULL; last = last->next) {
+				if (last->next == wss) {
+					last->next = wss->next;
+					break;
+				}
+			}
+		}
+		mem_free(wss);
+	}
+}
+
+// initiate websocket server on specified pcb
+static void ws_server_init_pcb( struct altcp_pcb *pcb, uint16_t port) {
+	err_t err;
+
+	if (pcb) {
+		altcp_setprio(pcb, TCP_PRIO_MIN);
+		err = altcp_bind(pcb, IP_ANY_TYPE, port);
+		LWIP_UNUSED_ARG(err);
+		LWIP_ASSERT("ws_server_init: tcp_bind failed", err == ERR_OK);
+		pcb = altcp_listen(pcb);
+		LWIP_ASSERT("ws_server_init: tcp_listen failed", pcb != NULL);
+		altcp_accept(pcb, ws_accept);
+	}
+}
+
+// initiate a websocket server
+void ws_server_init(void) {
+	struct altcp_pcb *pcb = altcp_tcp_new_ip_type(IPADDR_TYPE_ANY);
+	LWIP_ASSERT("ws_server_init: tcp_new failed", pcb != NULL);
+	ws_server_init_pcb(pcb, WS_PORT);
+}
+
+// set ws_receive_handler
+void ws_set_receive_handler( tWSHandler ws_handler)
+{
+	ws_receive_cb = ws_handler;
+}
+
+// set ws_open_handler
+void ws_set_open_handler( tWSOpenHandler ws_handler)
+{
+	ws_open_cb = ws_handler;
+}
+
+// callback for accepted websocket connection
+static err_t ws_accept(void *arg, struct altcp_pcb *pcb, err_t err) {
+	struct ws_state *wss;
+	LWIP_UNUSED_ARG(err);
+	LWIP_UNUSED_ARG(arg);
+	LWIP_DEBUGF(WS_DEBUG, ("ws_accept %p / %p\n", (void *)pcb, arg));
+
+	if ((err != ERR_OK) || (pcb == NULL)) {
+		return ERR_VAL;
+	}
+
+	// create new ws_state object
+	wss = ws_state_alloc();
+	if (wss == NULL) {
+		LWIP_DEBUGF(WS_DEBUG, ("ws_accept: Out of memory, RST\n"));
+		return ERR_MEM;
+	}
+	wss->pcb = pcb;
+
+	// make ws_state object the argument of callbacks
+	altcp_arg(pcb, wss);
+	
+	// register callbacks for tcp events
+	altcp_recv(pcb, ws_recv);
+	altcp_sent(pcb, ws_sent);
+	altcp_poll(pcb, ws_poll, WS_POLL_INTERVAL);
+	altcp_err(pcb, ws_err);
+
+	return ERR_OK;
+}
+
+// call when data is received
+static err_t ws_recv(void *arg, struct altcp_pcb *pcb, struct pbuf *p, err_t err) {
+	struct ws_state *wss = (struct ws_state *) arg;
+	
+	if ((err != ERR_OK) || (p == NULL) || (wss == NULL)) {
+		// error  or closed by client
+		if (p != NULL) {
+			// inform TCP that we have taken the data
+			altcp_recved(pcb, p->tot_len);
+			pbuf_free(p);
+		}
+		if (wss == NULL) {
+			// should not occur
+			LWIP_DEBUGF(WS_DEBUG, ("Error, ws_recv: wss is NULL, close\n"));
+		}
+		ws_close_conn(pcb, wss);
+		return ERR_OK;
+	}
+
+	if (wss->active) {
+		// process websocket message
+		err = ws_read(pcb, wss, p);
+	} else {
+		// init websocket connection
+		LWIP_DEBUGF(WS_DEBUG, ("ws_recv: websocket inactive, checking for handshake\n"));
+		
+		err = ws_handshake(pcb, wss, p);
+	}
+
+	// inform TCP that we have taken the data.
+	altcp_recved(pcb, p->tot_len);
+	pbuf_free(p);
+
+	if (err == ERR_CLSD) {
+		ws_close_conn(pcb, wss);
+	}
+
+	return ERR_OK;
+}
+
+// called when data has been sent over the websocket
+static err_t ws_sent(void *arg, struct altcp_pcb *pcb, uint16_t len) {
+	(void) pcb;
+
+	struct ws_state *wss = (struct ws_state *)arg;
+
+	LWIP_DEBUGF(WS_DEBUG | LWIP_DBG_TRACE, ("ws_sent %p\n", (void*) pcb));
+
+	LWIP_UNUSED_ARG(len);
+
+	if (wss == NULL) {
+		return ERR_OK;
+	}
+
+	wss->retries = 0;
+
+	return ERR_OK;
+}
+
+// called when there is a websocket error
+static void ws_err (void *arg, err_t err) {
+	struct ws_state *wss = (struct ws_state *) arg;
+	LWIP_UNUSED_ARG(err);
+
+	LWIP_DEBUGF(WS_DEBUG, ("ws_err: %s", lwip_strerr(err)));
+
+	if (wss != NULL) {
+		ws_state_free(wss);
+	}
+}
+
+// initiate close of connection
+static err_t ws_close_conn(struct altcp_pcb *pcb, struct ws_state *wss) {
+	return ws_close_or_abort_conn(pcb, wss, 0);
+}
+
+// call when closing connection or connection was aborted
+static err_t ws_close_or_abort_conn(struct altcp_pcb *pcb, struct ws_state *wss,
+	uint8_t abort_conn) {
+
+	err_t err;
+	LWIP_DEBUGF(WS_DEBUG, ("Closing connection %p\n", (void *)pcb));
+
+	// clear callbacks
+	altcp_arg(pcb, NULL);
+	altcp_recv(pcb, NULL);
+	altcp_sent(pcb, NULL);
+	altcp_poll(pcb, NULL, 0);
+	altcp_err(pcb, NULL);
+
+	// remove and free memory from ws_state object
+	if (wss != NULL) {
+		ws_state_free(wss);
+	}
+
+	if (abort_conn) {
+		altcp_abort(pcb);
+		return ERR_OK;
+	}
+	err = altcp_close(pcb);
+	if (err != ERR_OK) {
+		LWIP_DEBUGF(WS_DEBUG, ("Error %d closing %p\n", err, (void *)pcb));
+		// error closing, try again later in poll
+		altcp_poll(pcb, ws_poll, WS_POLL_INTERVAL);
+	}
+	return err;
+}
+
+// callback for polling process
+static err_t ws_poll(void *arg, struct altcp_pcb *pcb) {
+	struct ws_state *wss = (struct ws_state *) arg;
+	if (wss == NULL) {
+		err_t closed;
+		LWIP_DEBUGF(WS_DEBUG, ("ws_poll: arg is NULL, close\n"));
+		closed = ws_close_conn(pcb, NULL);
+		LWIP_UNUSED_ARG(closed);
+		if (closed == ERR_MEM) {
+			altcp_abort(pcb);
+			return ERR_ABRT;
+		}
+		return ERR_OK;
+	} else {
+		wss->retries++;
+		if (wss->retries == WS_MAX_RETRIES) {
+			LWIP_DEBUGF(WS_DEBUG, ("ws_poll: too may retries, close\n"));
+			ws_close_conn(pcb, wss);
+			return ERR_OK;
+		}
+	}
+
+	return ERR_OK;
+}
+
+// check for and complete handshake with client
+static err_t ws_handshake(struct altcp_pcb *pcb, struct ws_state *wss, struct pbuf *p){
+	uint8_t *data = (uint8_t *) p->payload;
+	uint16_t len = p->len;
+
+	// check if client is initiating a websocket connecttion
+	if (strstr(data, "Upgrade: websocket")) {
+		LWIP_DEBUGF(WS_DEBUG, ("ws_handshake: received websocket upgrade request\n"));
+
+		// search for websocket security key
+		char *key_start = strstr(data, "Sec-WebSocket-Key: ");
+
+		if (key_start) {
+			key_start += 19;
+			const char *key_end = strstr(key_start, "\r\n");
+			if (key_end) {
+				char key[64];
+				uint16_t key_len = key_end-key_start;
+				if ( (key_len>0) && (key_len + sizeof(WS_GUID) < sizeof(key)) ) {
+					// create response key by concatenating with websocket GUID,
+					// taking SHA1 hash, then encoding in base 64
+					strncpy(key, key_start, key_len);
+					strlcpy(&key[key_len], WS_GUID, sizeof(key)-key_len);
+
+					key_len += sizeof(WS_GUID)-1;
+					unsigned char key_sha1[20];
+					unsigned char key_base64[29];
+					size_t encoded_len;
+					mbedtls_sha1( (unsigned char *) key, key_len, key_sha1);
+					mbedtls_base64_encode( key_base64, 29, &encoded_len, key_sha1, 20);
+
+					// create response packet with encoded response key
+					unsigned char response[sizeof(WS_RESPONSE) + sizeof(key_base64)+3];
+					size_t count = sprintf(response, "%s%s\r\n\r\n", WS_RESPONSE, key_base64);
+
+					// send completed data packet
+					LWIP_DEBUGF(WS_DEBUG, ("ws_handshake: sending response\n"));
+					if(altcp_write(pcb, response, count, TCP_WRITE_FLAG_COPY) == ERR_OK) {
+						wss->active = true;
+					}
+
+					if (ws_open_cb != NULL) {
+						ws_open_cb(wss);
+					}
+
+					return ERR_OK;
+				}
+			}
+
+			LWIP_DEBUGF(WS_DEBUG, ("ws_handshake: key overflow\n"));
+			return ERR_MEM;
+		} else {
+			LWIP_DEBUGF(WS_DEBUG, ("ws_handshake: key not received\n"));
+			return ERR_ARG;
+		}
+	}
+
+	LWIP_DEBUGF(WS_DEBUG, ("ws_handshake: not a websocket request\n"));
+	return ERR_ARG;
+}
+
+// handle reading of websocket data and pass to ws_receive_cb
+static err_t ws_read(struct altcp_pcb *pcb, struct ws_state *wss, struct pbuf *p) {
+	(void) pcb;
+	uint8_t *data = (uint8_t *) p->payload;
+	uint16_t len = p->len;
+
+	if (data != NULL && len > 1) {
+		// successful read, reset timeout
+		wss->retries = 0;
+
+		uint8_t fin = data[0] & 0x80;
+		uint8_t opcode = data[0] & 0x0F;
+		uint8_t masked = data[1] & 0x80;
+		uint16_t msg_len = data[1] & 0x7F;
+		uint8_t *msg;
+		uint8_t *mask;
+
+		switch (msg_len) {
+			case 126: // next two bytes are length
+				msg_len = ( (uint16_t)data[2] << 8) | data[3];
+				if (len >= 8) {
+					msg = &data[8];
+					mask = &data[4];
+				}
+				break;
+			case 127: // next four bytes are length
+				// lwIP's pbuf only handles 16-bit lengths, so error
+				LWIP_DEBUGF(WS_DEBUG, ("ws_read: received 64-bit length %u\n", msg_len));
+				return ERR_MEM;
+			default:
+				if (len >= 6) {
+					msg = &data[6];
+					mask = &data[2];
+				}
+				break;
+		}
+		switch (opcode) {
+			case OP_CONT:
+				LWIP_DEBUGF(WS_DEBUG, ("ws_read: received continuation frame\n"));
+			case OP_TEXT:
+				LWIP_DEBUGF(WS_DEBUG, ("ws_read: received text data\n"));
+			case OP_BINARY:
+				LWIP_DEBUGF(WS_DEBUG, ("ws_read: decoding data, len=%u\n", msg_len));
+				if (msg && ws_receive_cb != NULL) {
+					// unmask the data if mask bit is received
+					if (masked) {
+						for (int i=0; i<msg_len; i++) {
+							msg[i] ^= mask[i % 4];
+						}
+					} else {
+						// messages from client must be masked - disconnect
+						LWIP_DEBUGF(WS_DEBUG, ("ws_read: received unmasked message"));
+						return ERR_CLSD;
+					}
+					msg[msg_len]=0;
+
+					if (opcode != OP_CONT) { // not a continuation frame, reset buffer
+						buf_len=0;
+						memset(buf, 0x00, sizeof(buf));
+					}
+
+					if (buf_len + msg_len > WS_BUFFER_SIZE) {
+						LWIP_DEBUGF(WS_DEBUG, ("ws_read: message exceeds buffer size %u+%u\n", buf_len, msg_len));
+						return ERR_MEM;
+					}
+
+					memcpy(&buf[buf_len], msg, msg_len);
+					buf_len += msg_len;
+					
+					if (fin) { // last packet in message, process completed message
+						ws_receive_cb(buf, buf_len);
+					}
+				}
+				break;
+			case OP_CLOSE:
+				LWIP_DEBUGF(WS_DEBUG, ("ws_read: close request"));
+				return ERR_CLSD;
+			case OP_PING:
+				// control frames cannot exceed 125 bytes in length
+				if (msg && msg_len <= 125) {
+					// send back a pong
+					uint8_t pong[2+msg_len];
+					pong[0]=0x8A;
+					pong[1]=msg_len;
+					memcpy(&pong[2], msg, msg_len);
+
+					return ws_send(wss, pong, msg_len+2);
+				}
+				return ERR_ARG;
+			case OP_PONG: // no response required for pong
+				return ERR_OK;
+			default:
+				LWIP_DEBUGF(WS_DEBUG, ("ws_read: invalid opcode %02X\n", opcode));
+				return ERR_ARG;
+		}
+
+		return ERR_OK;
+	}
+	LWIP_DEBUGF(WS_DEBUG, ("ws_read: received empty payload\n"));
+	return ERR_VAL;
+}
+
+static err_t ws_send(struct ws_state *wss, uint8_t *data, uint16_t len) {
+	uint8_t buf[128];
+	buf[0] = 0x81;
+	buf[1] = len & 0x7F;
+	memcpy(&buf[2], data, len);
+	
+	err_t err;
+	err = altcp_write(wss->pcb, buf, len+2, TCP_WRITE_FLAG_COPY);
+	if (err == ERR_OK) {
+		altcp_output(wss->pcb);
+	}
+
+	return err;
+}
+
+void ws_send_all(uint8_t *data, uint16_t len) {
+	// send message to all connections
+	if (ws_connections != NULL) {
+		struct ws_state *wss;
+		err_t err;
+		for (wss=ws_connections; wss != NULL; wss=wss->next) {
+			err = ws_send(wss, data, len);
+			if (err != ERR_OK ) {
+				LWIP_DEBUGF(WS_DEBUG, ("ws_send_all: error sending to %p\n", wss));
+			}
+		}
+	}
+}

websocket.h

@@ -0,0 +1,36 @@
+#ifndef WEBSOCKET_H_
+#define WEBSOCKET_H_
+
+#define WS_PORT				8080
+#define WS_TIMEOUT			10
+#define WS_DEBUG			LWIP_DBG_ON
+#define WS_MAX_RETRIES		10
+#define WS_POLL_INTERVAL	60 // WS_POLL_INTERVAL/2 seconds
+#define WS_MAX_CONN			4
+#define WS_BUFFER_SIZE		1024
+
+#define OP_CONT		0x00
+#define OP_TEXT		0x01
+#define OP_BINARY	0x02
+#define OP_CLOSE	0x08
+#define OP_PING		0x09
+#define OP_PONG		0x0A
+
+struct ws_state {
+	bool active;
+	uint8_t retries;
+	struct altcp_pcb *pcb;
+	struct ws_state *next;
+};
+
+#define WS_ALLOC_WS_STATE() (struct ws_state *)mem_malloc(sizeof(struct ws_state))
+
+typedef void (* tWSHandler ) (uint8_t *data, uint16_t len);
+typedef void (* tWSOpenHandler ) (struct ws_state * wss);
+
+void ws_server_init(void);
+void ws_send_all(uint8_t *data, uint16_t len);
+void ws_set_receive_handler( tWSHandler ws_handler);
+void ws_set_open_handler( tWSOpenHandler ws_handler);
+
+#endif