Udp

common/network/iceip.cxx

@@ -0,0 +1,185 @@
+/* Copyright (C) Kasm
+ *
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This software is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this software; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
+ * USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <arpa/inet.h>
+#include <errno.h>
+#include <limits.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#include <poll.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <time.h>
+#include <unistd.h>
+
+#include <network/iceip.h>
+#include <rfb/LogWriter.h>
+#include <rfb/ServerCore.h>
+
+static rfb::LogWriter vlog("ICE");
+
+// Default port 3478
+static const char * const servers[] = {
+	"stun.l.google.com:19302",
+	"stun1.l.google.com:19302",
+	"stun2.l.google.com:19302",
+	"stun3.l.google.com:19302",
+	"stun4.l.google.com:19302",
+	"stun.voipbuster.com",
+	"stun.voipstunt.com",
+};
+
+static bool tryserver(const char * const srv, const int sock) {
+
+	unsigned port = 3478;
+	char addr[PATH_MAX];
+	char buf[PATH_MAX];
+
+	const char *colon = strchr(srv, ':');
+	if (colon) {
+		memcpy(addr, srv, colon - srv);
+		addr[colon - srv] = '\0';
+
+		colon++;
+		port = atoi(colon);
+	} else {
+		strcpy(addr, srv);
+	}
+
+	vlog.debug("Trying '%s', port %u", addr, port);
+
+	struct hostent *ent = gethostbyname2(addr, AF_INET);
+	if (!ent)
+		return false;
+
+	struct sockaddr_in dst;
+	dst.sin_family = AF_INET;
+	dst.sin_port = htons(port);
+	memcpy(&dst.sin_addr, ent->h_addr, 4);
+	//vlog.info("Got %s, addr %s", ent->h_name, inet_ntoa(in));
+
+	// Build up a binding request packet
+	buf[0] = 0;
+	buf[1] = 1; // type
+	buf[2] = buf[3] = 0; // length
+
+	uint32_t tid[4]; // transaction id, 128 bits
+	tid[0] = rand();
+	tid[1] = rand();
+	tid[2] = rand();
+	tid[3] = rand();
+
+	memcpy(&buf[4], &tid[0], 4);
+	memcpy(&buf[8], &tid[1], 4);
+	memcpy(&buf[12], &tid[2], 4);
+	memcpy(&buf[16], &tid[3], 4);
+
+	if (sendto(sock, buf, 20, 0, (const struct sockaddr *) &dst,
+		sizeof(struct sockaddr_in)) != 20)
+		return false;
+
+	// Wait up to 10s for a reply, standard says that's the wait
+	struct pollfd pfd;
+	pfd.fd = sock;
+	pfd.events = POLLIN;
+	if (poll(&pfd, 1, 10 * 1000) <= 0)
+		return false;
+
+	struct sockaddr_in from;
+	socklen_t socklen = sizeof(struct sockaddr_in);
+	int len = recvfrom(sock, buf, PATH_MAX, 0, (struct sockaddr *) &from,
+				&socklen);
+	if (len < 20)
+		return false;
+	if (memcmp(&from.sin_addr, &dst.sin_addr, sizeof(struct in_addr)))
+		return false;
+
+	int i;
+/*	vlog.info("Got %u bytes", len);
+	for (i = 0; i < len; i++)
+		vlog.info("0x%02x,", buf[i]);*/
+
+	if (buf[0] != 1 || buf[1] != 1)
+		return false; // type not binding response
+
+	// Parse attrs
+	for (i = 20; i < len;) {
+		uint16_t type, attrlen;
+		memcpy(&type, &buf[i], 2);
+		i += 2;
+		memcpy(&attrlen, &buf[i], 2);
+		i += 2;
+
+		type = ntohs(type);
+		attrlen = ntohs(attrlen);
+		if (type != 1) {
+			// Not mapped-address
+			i += attrlen;
+			continue;
+		}
+
+		// Yay, we got a response
+		i += 4;
+		struct in_addr in;
+		memcpy(&in.s_addr, &buf[i], 4);
+
+		rfb::Server::publicIP.setParam(inet_ntoa(in));
+
+		vlog.info("My public IP is %s", (const char *) rfb::Server::publicIP);
+
+		return true;
+	}
+
+	return false;
+}
+
+void getPublicIP() {
+	if (rfb::Server::publicIP[0]) {
+		vlog.info("Using public IP %s from args",
+				(const char *) rfb::Server::publicIP);
+		return;
+	}
+
+	srand(time(NULL));
+
+	vlog.info("Querying public IP...");
+
+	const int sock = socket(AF_INET, SOCK_DGRAM, 0);
+	if (sock < 0)
+		abort();
+
+	unsigned i;
+	for (i = 0; i < sizeof(servers) / sizeof(servers[0]); i++) {
+		if (tryserver(servers[i], sock))
+			break;
+		vlog.info("STUN server %u didn't work, trying next...", i);
+	}
+
+	close(sock);
+
+	if (!rfb::Server::publicIP[0]) {
+		vlog.error("Failed to get public IP, please specify it with -publicIP");
+		exit(1);
+	}
+}