Complete WS connection establishment

author: cbdev <cb@cbcdn.com> 2019-05-18 13:12:46 +0200
committer: cbdev <cb@cbcdn.com> 2019-05-18 13:12:46 +0200
commit: ff94e4518d417d88f2fabdfca7025e68ce21849b (patch)
tree: 22232e7187cf5e7e9b03be84691a2b4f12de0645
parent: d28b5eb2960e80d80e967a3f01ce70e1fa457808 (diff)
download: websocksy-ff94e4518d417d88f2fabdfca7025e68ce21849b.tar.gz
websocksy-ff94e4518d417d88f2fabdfca7025e68ce21849b.tar.bz2
websocksy-ff94e4518d417d88f2fabdfca7025e68ce21849b.zip
6 files changed, 176 insertions, 96 deletions
diff --git a/index.html b/index.html
index 233ee69..8a9ae9c 100644
--- a/index.html
+++ b/index.html
@@ -1,8 +1,16 @@
 <html>
 	<head>
 		<script type="text/javascript">
+			var webSocket = null;
+
+			function openSocket(){
+				webSocket = new WebSocket("ws://localhost:8001/foo/bar");
+				webSocket.onclose = openSocket;
+			}
+
 			function init(){
-				var webSocket = new WebSocket("ws://localhost:8001/foo/bar");
+				openSocket();
+				setInterval(function(){webSocket.send("foo");}, 1000);
 			}
 		</script>
 	</head>
diff --git a/makefile b/makefile
index 90716a0..2d23909 100644
--- a/makefile
+++ b/makefile
@@ -1,9 +1,10 @@
 CFLAGS=-g -Wall -Wpedantic
+LDLIBS=-lnettle
 
 all: websocksy
 
 websocksy: websocksy.c websocksy.h ws_proto.c
-	$(CC) $(CFLAGS) $< -o $@
+	$(CC) $(CFLAGS) $(LDLIBS) $< -o $@
 
 clean:
 	rm websocksy
diff --git a/network.c b/network.c
new file mode 100644
index 0000000..9719b27
--- /dev/null
+++ b/network.c
@@ -0,0 +1,99 @@
+int network_socket(char* host, char* port, int socktype, int listener){
+	int fd = -1, status, yes = 1, flags;
+	struct addrinfo hints = {
+		.ai_family = AF_UNSPEC,
+		.ai_socktype = socktype,
+		.ai_flags = (listener ? AI_PASSIVE : 0)
+	};
+	struct addrinfo *info, *addr_it;
+
+	status = getaddrinfo(host, port, &hints, &info);
+	if(status){
+		fprintf(stderr, "Failed to parse address %s port %s: %s\n", host, port, gai_strerror(status));
+		return -1;
+	}
+
+	//traverse the result list
+	for(addr_it = info; addr_it; addr_it = addr_it->ai_next){
+		fd = socket(addr_it->ai_family, addr_it->ai_socktype, addr_it->ai_protocol);
+		if(fd < 0){
+			continue;
+		}
+
+		//set required socket options
+		yes = 1;
+		if(setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (void*)&yes, sizeof(yes)) < 0){
+			fprintf(stderr, "Failed to enable SO_REUSEADDR on socket: %s\n", strerror(errno));
+		}
+
+		yes = 0;
+		if(setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, (void*)&yes, sizeof(yes)) < 0){
+			fprintf(stderr, "Failed to unset IPV6_V6ONLY on socket: %s\n", strerror(errno));
+		}
+
+		//TODO loop, bcast for udp
+
+		if(listener){
+			status = bind(fd, addr_it->ai_addr, addr_it->ai_addrlen);
+			if(status < 0){
+				close(fd);
+				continue;
+			}
+		}
+		else{
+			status = connect(fd, addr_it->ai_addr, addr_it->ai_addrlen);
+			if(status < 0){
+				close(fd);
+				continue;
+			}
+		}
+
+		break;
+	}
+	freeaddrinfo(info);
+
+	if(!addr_it){
+		fprintf(stderr, "Failed to create socket for %s port %s\n", host, port);
+		return -1;
+	}
+
+	//set nonblocking
+	flags = fcntl(fd, F_GETFL, 0);
+	if(fcntl(fd, F_SETFL, flags | O_NONBLOCK) < 0){
+		fprintf(stderr, "Failed to set socket nonblocking: %s\n", strerror(errno));
+		close(fd);
+		return -1;
+	}
+
+	if(!listener){
+		return fd;
+	}
+
+	if(socktype == SOCK_STREAM){
+		status = listen(fd, SOMAXCONN);
+		if(status < 0){
+			fprintf(stderr, "Failed to listen on socket: %s\n", strerror(errno));
+			close(fd);
+			return -1;
+		}
+	}
+
+	return fd;
+}
+
+int network_send(int fd, uint8_t* data, size_t length){
+	ssize_t total = 0, sent;
+	while(total < length){
+		sent = send(fd, data + total, length - total, 0);
+		if(sent < 0){
+			fprintf(stderr, "Failed to send: %s\n", strerror(errno));
+			return 1;
+		}
+		total += sent;
+	}
+	return 0;
+}
+
+int network_send_str(int fd, char* data){
+	return network_send(fd, (uint8_t*) data, strlen(data));
+}
+\ No newline at end of file
diff --git a/websocksy.c b/websocksy.c
index f193ae6..ca7193b 100644
--- a/websocksy.c
+++ b/websocksy.c
@@ -10,6 +10,7 @@
 #include <fcntl.h>
 
 #include "websocksy.h"
+#include "network.c"
 #include "ws_proto.c"
 
 /* TODO
@@ -36,89 +37,6 @@ int args_parse(int argc, char** argv){
 	return 0;
 }
 
-int network_socket(char* host, char* port, int socktype, int listener){
-	int fd = -1, status, yes = 1, flags;
-	struct addrinfo hints = {
-		.ai_family = AF_UNSPEC,
-		.ai_socktype = socktype,
-		.ai_flags = (listener ? AI_PASSIVE : 0)
-	};
-	struct addrinfo *info, *addr_it;
-
-	status = getaddrinfo(host, port, &hints, &info);
-	if(status){
-		fprintf(stderr, "Failed to parse address %s port %s: %s\n", host, port, gai_strerror(status));
-		return -1;
-	}
-
-	//traverse the result list
-	for(addr_it = info; addr_it; addr_it = addr_it->ai_next){
-		fd = socket(addr_it->ai_family, addr_it->ai_socktype, addr_it->ai_protocol);
-		if(fd < 0){
-			continue;
-		}
-
-		//set required socket options
-		yes = 1;
-		if(setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (void*)&yes, sizeof(yes)) < 0){
-			fprintf(stderr, "Failed to enable SO_REUSEADDR on socket: %s\n", strerror(errno));
-		}
-
-		yes = 0;
-		if(setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, (void*)&yes, sizeof(yes)) < 0){
-			fprintf(stderr, "Failed to unset IPV6_V6ONLY on socket: %s\n", strerror(errno));
-		}
-
-		//TODO loop, bcast for udp
-
-		if(listener){
-			status = bind(fd, addr_it->ai_addr, addr_it->ai_addrlen);
-			if(status < 0){
-				close(fd);
-				continue;
-			}
-		}
-		else{
-			status = connect(fd, addr_it->ai_addr, addr_it->ai_addrlen);
-			if(status < 0){
-				close(fd);
-				continue;
-			}
-		}
-
-		break;
-	}
-	freeaddrinfo(info);
-
-	if(!addr_it){
-		fprintf(stderr, "Failed to create socket for %s port %s\n", host, port);
-		return -1;
-	}
-
-	//set nonblocking
-	flags = fcntl(fd, F_GETFL, 0);
-	if(fcntl(fd, F_SETFL, flags | O_NONBLOCK) < 0){
-		fprintf(stderr, "Failed to set socket nonblocking: %s\n", strerror(errno));
-		close(fd);
-		return -1;
-	}
-
-	if(!listener){
-		return fd;
-	}
-
-	if(socktype == SOCK_STREAM){
-		status = listen(fd, SOMAXCONN);
-		if(status < 0){
-			fprintf(stderr, "Failed to listen on socket: %s\n", strerror(errno));
-			close(fd);
-			return -1;
-		}
-	}
-
-	return fd;
-}
-
 int ws_peer_data(websocket* ws){
 	//TODO
 	return -1;
@@ -139,6 +57,8 @@ int main(int argc, char** argv){
 		exit(usage(argv[0]));
 	}
 
+	signal(SIGINT, signal_handler);
+
 	//core loop
 	while(!shutdown_requested){
 		FD_ZERO(&read_fds);
diff --git a/websocksy.h b/websocksy.h
index 794b4ed..275b9ab 100644
--- a/websocksy.h
+++ b/websocksy.h
@@ -1,12 +1,14 @@
 #include <stdint.h>
 #include <stdlib.h>
+#include <nettle/sha1.h>
+#include <nettle/base64.h>
 
 #define WS_MAX_LINE 16384
 
 typedef enum {
 	ws_new = 0,
 	ws_http,
-	ws_rfc6455
+	ws_open
 } ws_state;
 
 struct {
diff --git a/ws_proto.c b/ws_proto.c
index b9f92e9..7da6698 100644
--- a/ws_proto.c
+++ b/ws_proto.c
@@ -1,5 +1,7 @@
 #include <ctype.h>
 
+#define RFC6455_MAGIC_KEY "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"
+
 static size_t socks = 0;
 static websocket* sock = NULL;
 
@@ -96,15 +98,52 @@ int ws_handle_new(websocket* ws){
 
 int ws_upgrade_http(websocket* ws){
 	if(ws->websocket_version == 13
+			&& ws->socket_key
 			&& ws->want_upgrade){
+		if(network_send_str(ws->fd, "HTTP/1.1 101 Upgrading\r\n")
+				|| network_send_str(ws->fd, "Upgrade: websocket\r\n")
+				|| network_send_str(ws->fd, "Connection: Upgrade\r\n")){
+			//TODO might want to disconnect here
+			return 1;
+		}
 
-		return 0;
+		//calculate the websocket key which for some reason is defined as
+		//base64(sha1(concat(trim(client-key), "258EAFA5-E914-47DA-95CA-C5AB0DC85B11")))
+		//which requires not one but 2 unnecessarily complex operations
+		size_t encode_offset = 0;
+		struct sha1_ctx ws_accept_ctx;
+		struct base64_encode_ctx ws_accept_encode;
+		uint8_t ws_accept_digest[SHA1_DIGEST_SIZE];
+		char ws_accept_key[BASE64_ENCODE_LENGTH(SHA1_DIGEST_SIZE) + 3] = "";
+		sha1_init(&ws_accept_ctx);
+		sha1_update(&ws_accept_ctx, strlen(ws->socket_key), (uint8_t*) ws->socket_key);
+		sha1_update(&ws_accept_ctx, strlen(RFC6455_MAGIC_KEY), (uint8_t*) RFC6455_MAGIC_KEY);
+		sha1_digest(&ws_accept_ctx, sizeof(ws_accept_digest), (uint8_t*) &ws_accept_digest);
+		base64_encode_init(&ws_accept_encode);
+		encode_offset = base64_encode_update(&ws_accept_encode, (uint8_t*) ws_accept_key, SHA1_DIGEST_SIZE, ws_accept_digest);
+		encode_offset += base64_encode_final(&ws_accept_encode, (uint8_t*) ws_accept_key + encode_offset);
+		memcpy(ws_accept_key + encode_offset, "\r\n\0", 3);
+
+		//send websocket accept key
+		if(network_send_str(ws->fd, "Sec-WebSocket-Accept: ")
+					|| network_send_str(ws->fd, ws_accept_key)){
+			return 1;
+		}
+
+		//TODO Sec-Websocket-Protocol
+		//TODO find/connect peer
+
+		ws->state = ws_open;
+		return network_send_str(ws->fd, "\r\n") ? 1 : 0;
 	}
+	//TODO RFC 4.2.2.4: An unsupported version must be answered with HTTP 426
 	return 1;
 }
 
 int ws_handle_http(websocket* ws){
 	char* header, *value;
+	ssize_t p;
+
 	if(!ws->read_buffer[0]){
 		return ws_upgrade_http(ws);
 	}
@@ -130,6 +169,10 @@ int ws_handle_http(websocket* ws){
 		ws->websocket_version = strtoul(value, NULL, 10);
 	}
 	else if(!strcmp(header, "Sec-WebSocket-Key")){
+		//right-trim the key
+		for(p = strlen(value) - 1; p >= 0 && isspace(value[p]); p--){
+			value[p] = 0;
+		}
 		ws->socket_key = strdup(value);
 	}
 	else if(!strcmp(header, "Upgrade") && !strcmp(value, "websocket")){
@@ -139,8 +182,15 @@ int ws_handle_http(websocket* ws){
 	return 0;
 }
 
+int ws_frame(websocket* ws){
+	//TODO check for complete WS frame
+	//read/handle/forward data
+	fprintf(stderr, "Incoming websocket data\n");
+	return 0;
+}
+
 int ws_data(websocket* ws){
-	ssize_t bytes_read, u, bytes_left = sizeof(ws->read_buffer) - ws->read_buffer_offset;
+	ssize_t bytes_read, n, bytes_left = sizeof(ws->read_buffer) - ws->read_buffer_offset;
 	int rv = 0;
 
 	bytes_read = recv(ws->fd, ws->read_buffer + ws->read_buffer_offset, bytes_left - 1, 0);
@@ -162,10 +212,10 @@ int ws_data(websocket* ws){
 		case ws_new:
 		case ws_http:
 			//scan for newline, handle line
-			for(u = 0; u < bytes_read - 1; u++){
-				if(!strncmp((char*) ws->read_buffer + ws->read_buffer_offset + u, "\r\n", 2)){
+			for(n = 0; n < bytes_read - 1; n++){
+				if(!strncmp((char*) ws->read_buffer + ws->read_buffer_offset + n, "\r\n", 2)){
 					//terminate line
-					ws->read_buffer[ws->read_buffer_offset + u] = 0;
+					ws->read_buffer[ws->read_buffer_offset + n] = 0;
 
 					if(ws->state == ws_new){
 						rv |= ws_handle_new(ws);
@@ -176,17 +226,17 @@ int ws_data(websocket* ws){
 					//TODO handle rv
 
 					//remove from buffer
-					bytes_read -= (u + 2);
-					memmove(ws->read_buffer, ws->read_buffer + ws->read_buffer_offset + u + 2, bytes_read);
+					bytes_read -= (n + 2);
+					memmove(ws->read_buffer, ws->read_buffer + ws->read_buffer_offset + n + 2, bytes_read);
 					ws->read_buffer_offset = 0;
 
 					//restart from the beginning
-					u = -1;
+					n = -1;
 				}
 			}
 			break;
-		//case ws_rfc6455:
-			//TODO parse websocket encap, forward to peer
+		case ws_open:
+			rv |= ws_frame(ws);
 	}
 
 	//update read buffer offset
author	cbdev <cb@cbcdn.com>	2019-05-18 13:12:46 +0200
committer	cbdev <cb@cbcdn.com>	2019-05-18 13:12:46 +0200
commit	ff94e4518d417d88f2fabdfca7025e68ce21849b (patch)
tree	22232e7187cf5e7e9b03be84691a2b4f12de0645
parent	d28b5eb2960e80d80e967a3f01ce70e1fa457808 (diff)
download	websocksy-ff94e4518d417d88f2fabdfca7025e68ce21849b.tar.gz websocksy-ff94e4518d417d88f2fabdfca7025e68ce21849b.tar.bz2 websocksy-ff94e4518d417d88f2fabdfca7025e68ce21849b.zip