stun

commit 1f6a67becbfda9dd710fbff590dbc295979f0c7f
parent 2418a494cd09bbe4d42553c1cc941c1a0004913a
Author: sin <sin@2f30.org>
Date:   Mon, 21 Mar 2016 10:14:38 +0000

cleanup

Diffstat:
M
README
 | 
2
--
M
stun.c
 | 
126
+++++++++++++++++++++++++++++++++++++++++--------------------------------------

2 files changed, 65 insertions(+), 63 deletions(-)
diff --git a/README b/README
@@ -14,13 +14,11 @@ Usage
 
 On the server:
 
-	ifconfig tun0 create
 	ifconfig tun0 10.0.0.1 10.0.0.2
 	STUNPW="password" stun -s /dev/tun0
 
 On the client:
 
-	ifconfig tun0 create
 	ifconfig tun0 10.0.0.2 10.0.0.1
 	STUNPW="password" stun -h ip-of-server /dev/tun0
 
diff --git a/stun.c b/stun.c
@@ -29,8 +29,8 @@
 #define MTU		1440
 
 EVP_CIPHER_CTX enc, dec;
+struct sockaddr_in local, remote;
 char *argv0;
-char *tundev;
 char *host;
 int port = 12080;
 int debug;
@@ -233,13 +233,13 @@ loop(int netfd, int tunfd)
 {
 	unsigned char buf[MTU + AES_BLOCK_SIZE + HDRLEN];
 	struct pollfd pfd[2];
-	int n, ret;
+	int ret, n;
 
 	pfd[0].fd = netfd;
 	pfd[0].events = POLLIN;
 	pfd[1].fd = tunfd;
 	pfd[1].events = POLLIN;
-	while (1) {
+	for (;;) {
 		ret = poll(pfd, 2, -1);
 		if (ret < 0)
 			err(1, "poll");
@@ -249,13 +249,64 @@ loop(int netfd, int tunfd)
 		if (pfd[1].revents & (POLLIN | POLLHUP))
 			if ((n = readtun(tunfd, buf, MTU)) <= 0 ||
 			    (n = writenet(netfd, buf, n)) <= 0)
-				return -1;
+				return 1;
 		if (pfd[0].revents & (POLLIN | POLLHUP))
 			if ((n = readnet(netfd, buf, MTU)) <= 0 ||
 			    (n = writetun(tunfd, buf, n)) <= 0)
-				return -1;
+				return 1;
+	}
+	return 0;
+}
+
+int
+serversetup(int tunfd)
+{
+	int ret, netfd, listenfd;
+
+	listenfd = socket(AF_INET, SOCK_STREAM, 0);
+	if (listenfd < 0)
+		err(1, "socket");
+	setsockopt(listenfd, SOL_SOCKET, SO_REUSEADDR, (int []){1}, sizeof(int));
+	memset(&local, 0, sizeof(local));
+	local.sin_family = AF_INET;
+	local.sin_addr.s_addr = htonl(INADDR_ANY);
+	local.sin_port = htons(port);
+	ret = bind(listenfd, (struct sockaddr *)&local, sizeof(local));
+	if (ret < 0)
+		err(1, "bind");
+	ret = listen(listenfd, 5);
+	if (ret < 0)
+		err(1, "listen");
+	for (;;) {
+		netfd = accept(listenfd, (struct sockaddr *)&remote,
+		               (socklen_t []){sizeof(remote)});
+		if (ret < 0)
+			err(1, "accept");
+		if (debug)
+			printf("client connected\n");
+		setsockopt(netfd, IPPROTO_TCP, TCP_NODELAY, (int []){1}, sizeof(int));
+		loop(netfd, tunfd);
+		close(netfd);
 	}
-	return 0; /* unreachable */
+}
+
+int
+clientsetup(int tunfd)
+{
+	int ret, netfd;
+
+	netfd = socket(AF_INET, SOCK_STREAM, 0);
+	if (netfd < 0)
+		err(1, "socket");
+	memset(&remote, 0, sizeof(remote));
+	remote.sin_family = AF_INET;
+	remote.sin_addr.s_addr = inet_addr(host);
+	remote.sin_port = htons(port);
+	ret = connect(netfd, (struct sockaddr *)&remote, sizeof(remote));
+	if (ret < 0)
+		err(1, "connect");
+	setsockopt(netfd, IPPROTO_TCP, TCP_NODELAY, (int []){1}, sizeof(int));
+	return loop(netfd, tunfd);
 }
 
 void
@@ -268,10 +319,9 @@ usage(void)
 int
 main(int argc, char *argv[])
 {
-	struct sockaddr_in local, remote;
 	char *pw;
 	const char *errstr;
-	int ret, tunfd, netfd = -1, listenfd;
+	int ret, tunfd;
 
 	ARGBEGIN {
 	case 'd':
@@ -292,64 +342,18 @@ main(int argc, char *argv[])
 		usage();
 	} ARGEND
 
-	if (argc != 1) usage();
-	tundev = argv[0];
-
-	tunfd = opentun(tundev);
-
+	if (argc != 1 || (!sflag && !host))
+		usage();
+	tunfd = opentun(argv[0]);
 	pw = getenv("STUNPW");
 	if (!pw)
 		errx(1, "STUNPW is not set");
 	if (aesinit((unsigned char *)pw, strlen(pw), &enc, &dec) < 0)
 		errx(1, "couldn't initialize AES cipher");
 	explicit_bzero(pw, strlen(pw));
-
-	if (sflag) {
-		/* server */
-		listenfd = socket(AF_INET, SOCK_STREAM, 0);
-		if (listenfd < 0)
-			err(1, "socket");
-		setsockopt(listenfd, SOL_SOCKET, SO_REUSEADDR, (int []){1}, sizeof(int));
-		memset(&local, 0, sizeof(local));
-		local.sin_family = AF_INET;
-		local.sin_addr.s_addr = htonl(INADDR_ANY);
-		local.sin_port = htons(port);
-		ret = bind(listenfd, (struct sockaddr *)&local, sizeof(local));
-		if (ret < 0)
-			err(1, "bind");
-		ret = listen(listenfd, 5);
-		if (ret < 0)
-			err(1, "listen");
-	} else {
-		/* client */
-		if (!host)
-			usage();
-		netfd = socket(AF_INET, SOCK_STREAM, 0);
-		if (netfd < 0)
-			err(1, "socket");
-		memset(&remote, 0, sizeof(remote));
-		remote.sin_family = AF_INET;
-		remote.sin_addr.s_addr = inet_addr(host);
-		remote.sin_port = htons(port);
-		ret = connect(netfd, (struct sockaddr *)&remote, sizeof(remote));
-		if (ret < 0)
-			err(1, "connect");
-	}
-
-again:
-	if (sflag) {
-		if (netfd != -1)
-			close(netfd);
-		netfd = accept(listenfd, (struct sockaddr *)&remote,
-		               (socklen_t []){sizeof(remote)});
-		if (ret < 0)
-			err(1, "accept");
-		if (debug)
-			printf("client connected\n");
-	}
-	setsockopt(netfd, IPPROTO_TCP, TCP_NODELAY, (int []){1}, sizeof(int));
-	if (loop(netfd, tunfd) < 0 && sflag)
-		goto again;
+	if (sflag)
+		return serversetup(tunfd);
+	ret = clientsetup(tunfd);
 	warnx("connection dropped");
-	exit(1);
+	return ret;
 }