X-Git-Url: https://git.librecmc.org/?p=oweals%2Ftinc.git;a=blobdiff_plain;f=src%2Fnet_setup.c;h=d7668885e7f76ca6965f9bfbf3b6ab80a47bb1df;hp=c4337ccc35021a702bc58b0dfedbd1f702d78cb0;hb=8bf4c160d69d980f818ca05ba482b2ffa8230632;hpb=e838289683c0039fac0ae6172d40b4177c17911b

diff --git a/src/net_setup.c b/src/net_setup.c
index c4337cc..d766888 100644
--- a/src/net_setup.c
+++ b/src/net_setup.c
@@ -1,7 +1,7 @@
 /*
     net_setup.c -- Setup.
     Copyright (C) 1998-2005 Ivo Timmermans,
-                  2000-2010 Guus Sliepen <guus@tinc-vpn.org>
+                  2000-2016 Guus Sliepen <guus@tinc-vpn.org>
                   2006      Scott Lamb <slamb@slamb.org>
                   2010      Brandon Black <blblack@gmail.com>
 
@@ -39,17 +39,31 @@
 #include "netutl.h"
 #include "process.h"
 #include "protocol.h"
+#include "proxy.h"
 #include "route.h"
 #include "subnet.h"
 #include "utils.h"
 #include "xalloc.h"
 
 char *myport;
+devops_t devops;
+
+#ifndef HAVE_RSA_SET0_KEY
+int RSA_set0_key(RSA *r, BIGNUM *n, BIGNUM *e, BIGNUM *d) {
+	BN_free(r->n); r->n = n;
+	BN_free(r->e); r->e = e;
+	BN_free(r->d); r->d = d;
+	return 1;
+}
+#endif
 
 bool read_rsa_public_key(connection_t *c) {
 	FILE *fp;
-	char *fname;
+	char *pubname;
+	char *hcfname;
 	char *key;
+	BIGNUM *n = NULL;
+	BIGNUM *e = NULL;
 
 	if(!c->rsa_key) {
 		c->rsa_key = RSA_new();
@@ -59,88 +73,97 @@ bool read_rsa_public_key(connection_t *c) {
 	/* First, check for simple PublicKey statement */
 
 	if(get_config_string(lookup_config(c->config_tree, "PublicKey"), &key)) {
-		BN_hex2bn(&c->rsa_key->n, key);
-		BN_hex2bn(&c->rsa_key->e, "FFFF");
+		if(BN_hex2bn(&n, key) != strlen(key)) {
+			free(key);
+			logger(LOG_ERR, "Invalid PublicKey for %s!", c->name);
+			return false;
+		}
 		free(key);
+		BN_hex2bn(&e, "FFFF");
+		if(!n || !e || RSA_set0_key(c->rsa_key, n, e, NULL) != 1) {
+			BN_free(e);
+			BN_free(n);
+			logger(LOG_ERR, "RSA_set0_key() failed with PublicKey for %s!", c->name);
+			return false;
+		}
 		return true;
 	}
 
 	/* Else, check for PublicKeyFile statement and read it */
 
-	if(get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &fname)) {
-		fp = fopen(fname, "r");
+	if(get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &pubname)) {
+		fp = fopen(pubname, "r");
 
 		if(!fp) {
-			logger(LOG_ERR, "Error reading RSA public key file `%s': %s",
-				   fname, strerror(errno));
-			free(fname);
+			logger(LOG_ERR, "Error reading RSA public key file `%s': %s", pubname, strerror(errno));
+			free(pubname);
 			return false;
 		}
 
-		free(fname);
 		c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
 		fclose(fp);
 
-		if(c->rsa_key)
+		if(c->rsa_key) {
+			free(pubname);
 			return true;		/* Woohoo. */
+		}
 
 		/* If it fails, try PEM_read_RSA_PUBKEY. */
-		fp = fopen(fname, "r");
+		fp = fopen(pubname, "r");
 
 		if(!fp) {
-			logger(LOG_ERR, "Error reading RSA public key file `%s': %s",
-				   fname, strerror(errno));
-			free(fname);
+			logger(LOG_ERR, "Error reading RSA public key file `%s': %s", pubname, strerror(errno));
+			free(pubname);
 			return false;
 		}
 
-		free(fname);
 		c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
 		fclose(fp);
 
 		if(c->rsa_key) {
 //				RSA_blinding_on(c->rsa_key, NULL);
+			free(pubname);
 			return true;
 		}
 
-		logger(LOG_ERR, "Reading RSA public key file `%s' failed: %s",
-			   fname, strerror(errno));
+		logger(LOG_ERR, "Reading RSA public key file `%s' failed: %s", pubname, strerror(errno));
+		free(pubname);
 		return false;
 	}
 
 	/* Else, check if a harnessed public key is in the config file */
 
-	xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
-	fp = fopen(fname, "r");
+	xasprintf(&hcfname, "%s/hosts/%s", confbase, c->name);
+	fp = fopen(hcfname, "r");
 
 	if(!fp) {
-		logger(LOG_ERR, "Error reading RSA public key file `%s': %s", fname, strerror(errno));
-		free(fname);
-		return;
+		logger(LOG_ERR, "Error reading RSA public key file `%s': %s", hcfname, strerror(errno));
+		free(hcfname);
+		return false;
 	}
 
 	c->rsa_key = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
 	fclose(fp);
-	free(fname);
 
-	if(c->rsa_key)
+	if(c->rsa_key) {
+		free(hcfname);
 		return true;
+	}
 
 	/* Try again with PEM_read_RSA_PUBKEY. */
 
-	xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
-	fp = fopen(fname, "r");
+	fp = fopen(hcfname, "r");
 
 	if(!fp) {
-		logger(LOG_ERR, "Error reading RSA public key file `%s': %s", fname, strerror(errno));
-		free(fname);
-		return;
+		logger(LOG_ERR, "Error reading RSA public key file `%s': %s", hcfname, strerror(errno));
+		free(hcfname);
+		return false;
 	}
 
+	free(hcfname);
 	c->rsa_key = PEM_read_RSA_PUBKEY(fp, &c->rsa_key, NULL, NULL);
 //	RSA_blinding_on(c->rsa_key, NULL);
 	fclose(fp);
-	free(fname);
 
 	if(c->rsa_key)
 		return true;
@@ -153,20 +176,39 @@ bool read_rsa_public_key(connection_t *c) {
 static bool read_rsa_private_key(void) {
 	FILE *fp;
 	char *fname, *key, *pubkey;
-	struct stat s;
+	BIGNUM *n = NULL;
+	BIGNUM *e = NULL;
+	BIGNUM *d = NULL;
 
 	if(get_config_string(lookup_config(config_tree, "PrivateKey"), &key)) {
+		myself->connection->rsa_key = RSA_new();
+//		RSA_blinding_on(myself->connection->rsa_key, NULL);
+		if(BN_hex2bn(&d, key) != strlen(key)) {
+			logger(LOG_ERR, "Invalid PrivateKey for myself!");
+			free(key);
+			return false;
+		}
+		free(key);
 		if(!get_config_string(lookup_config(config_tree, "PublicKey"), &pubkey)) {
+			BN_free(d);
 			logger(LOG_ERR, "PrivateKey used but no PublicKey found!");
 			return false;
 		}
-		myself->connection->rsa_key = RSA_new();
-//		RSA_blinding_on(myself->connection->rsa_key, NULL);
-		BN_hex2bn(&myself->connection->rsa_key->d, key);
-		BN_hex2bn(&myself->connection->rsa_key->n, pubkey);
-		BN_hex2bn(&myself->connection->rsa_key->e, "FFFF");
-		free(key);
+		if(BN_hex2bn(&n, pubkey) != strlen(pubkey)) {
+			free(pubkey);
+			BN_free(d);
+			logger(LOG_ERR, "Invalid PublicKey for myself!");
+			return false;
+		}
 		free(pubkey);
+		BN_hex2bn(&e, "FFFF");
+		if(!n || !e || !d || RSA_set0_key(myself->connection->rsa_key, n, e, d) != 1) {
+			BN_free(d);
+			BN_free(e);
+			BN_free(n);
+			logger(LOG_ERR, "RSA_set0_key() failed with PrivateKey for myself!");
+			return false;
+		}
 		return true;
 	}
 
@@ -183,15 +225,14 @@ static bool read_rsa_private_key(void) {
 	}
 
 #if !defined(HAVE_MINGW) && !defined(HAVE_CYGWIN)
-	if(fstat(fileno(fp), &s)) {
-		logger(LOG_ERR, "Could not stat RSA private key file `%s': %s'",
-				fname, strerror(errno));
-		free(fname);
-		return false;
-	}
+	struct stat s;
 
-	if(s.st_mode & ~0100700)
-		logger(LOG_WARNING, "Warning: insecure file permissions for RSA private key file `%s'!", fname);
+	if(!fstat(fileno(fp), &s)) {
+		if(s.st_mode & ~0100700)
+			logger(LOG_WARNING, "Warning: insecure file permissions for RSA private key file `%s'!", fname);
+	} else {
+		logger(LOG_WARNING, "Could not stat RSA private key file `%s': %s'", fname, strerror(errno));
+	}
 #endif
 
 	myself->connection->rsa_key = PEM_read_RSAPrivateKey(fp, NULL, NULL, NULL);
@@ -220,7 +261,6 @@ void load_all_subnets(void) {
 	config_t *cfg;
 	subnet_t *s, *s2;
 	node_t *n;
-	bool result;
 
 	xasprintf(&dname, "%s/hosts", confbase);
 	dir = opendir(dname);
@@ -242,10 +282,9 @@ void load_all_subnets(void) {
 
 		xasprintf(&fname, "%s/hosts/%s", confbase, ent->d_name);
 		init_configuration(&config_tree);
-		result = read_config_file(config_tree, fname);
+		read_config_options(config_tree, ent->d_name);
+		read_config_file(config_tree, fname);
 		free(fname);
-		if(!result)
-			continue;
 
 		if(!n) {
 			n = new_node();
@@ -270,20 +309,64 @@ void load_all_subnets(void) {
 	closedir(dir);
 }
 
+char *get_name(void) {
+	char *name = NULL;
+
+	get_config_string(lookup_config(config_tree, "Name"), &name);
+
+	if(!name)
+		return NULL;
+
+	if(*name == '$') {
+		char *envname = getenv(name + 1);
+		char hostname[32] = "";
+		if(!envname) {
+			if(strcmp(name + 1, "HOST")) {
+				fprintf(stderr, "Invalid Name: environment variable %s does not exist\n", name + 1);
+				free(name);
+				return false;
+			}
+			if(gethostname(hostname, sizeof hostname) || !*hostname) {
+				fprintf(stderr, "Could not get hostname: %s\n", strerror(errno));
+				free(name);
+				return false;
+			}
+			hostname[31] = 0;
+			envname = hostname;
+		}
+		free(name);
+		name = xstrdup(envname);
+		for(char *c = name; *c; c++)
+			if(!isalnum(*c))
+				*c = '_';
+	}
+
+	if(!check_id(name)) {
+		logger(LOG_ERR, "Invalid name for myself!");
+		free(name);
+		return false;
+	}
+
+	return name;
+}
+
 /*
   Configure node_t myself and set up the local sockets (listen only)
 */
 static bool setup_myself(void) {
 	config_t *cfg;
 	subnet_t *subnet;
-	char *name, *hostname, *mode, *afname, *cipher, *digest;
+	char *name, *hostname, *mode, *afname, *cipher, *digest, *type;
 	char *fname = NULL;
 	char *address = NULL;
-	char *envp[5];
+	char *proxy = NULL;
+	char *space;
+	char *envp[5] = {NULL};
 	struct addrinfo *ai, *aip, hint = {0};
 	bool choice;
 	int i, err;
 	int replaywin_int;
+	bool port_specified = false;
 
 	myself = new_node();
 	myself->connection = new_connection();
@@ -294,16 +377,12 @@ static bool setup_myself(void) {
 	myself->connection->options = 0;
 	myself->connection->protocol_version = PROT_CURRENT;
 
-	if(!get_config_string(lookup_config(config_tree, "Name"), &name)) {	/* Not acceptable */
+	if(!(name = get_name())) {
 		logger(LOG_ERR, "Name for tinc daemon required!");
 		return false;
 	}
 
-	if(!check_id(name)) {
-		logger(LOG_ERR, "Invalid name for myself!");
-		free(name);
-		return false;
-	}
+	/* Read tinc.conf and our own host config file */
 
 	myself->name = name;
 	myself->connection->name = xstrdup(name);
@@ -317,6 +396,10 @@ static bool setup_myself(void) {
 
 	if(!get_config_string(lookup_config(config_tree, "Port"), &myport))
 		myport = xstrdup("655");
+	else
+		port_specified = true;
+
+	/* Ensure myport is numeric */
 
 	if(!atoi(myport)) {
 		struct addrinfo *ai = str2addrinfo("localhost", myport, SOCK_DGRAM);
@@ -328,6 +411,70 @@ static bool setup_myself(void) {
 		sockaddr2str(&sa, NULL, &myport);
 	}
 
+	if(get_config_string(lookup_config(config_tree, "Proxy"), &proxy)) {
+		if((space = strchr(proxy, ' ')))
+			*space++ = 0;
+
+		if(!strcasecmp(proxy, "none")) {
+			proxytype = PROXY_NONE;
+		} else if(!strcasecmp(proxy, "socks4")) {
+			proxytype = PROXY_SOCKS4;
+		} else if(!strcasecmp(proxy, "socks4a")) {
+			proxytype = PROXY_SOCKS4A;
+		} else if(!strcasecmp(proxy, "socks5")) {
+			proxytype = PROXY_SOCKS5;
+		} else if(!strcasecmp(proxy, "http")) {
+			proxytype = PROXY_HTTP;
+		} else if(!strcasecmp(proxy, "exec")) {
+			proxytype = PROXY_EXEC;
+		} else {
+			logger(LOG_ERR, "Unknown proxy type %s!", proxy);
+			free(proxy);
+			return false;
+		}
+
+		switch(proxytype) {
+			case PROXY_NONE:
+			default:
+				break;
+
+			case PROXY_EXEC:
+				if(!space || !*space) {
+					logger(LOG_ERR, "Argument expected for proxy type exec!");
+					free(proxy);
+					return false;
+				}
+				proxyhost =  xstrdup(space);
+				break;
+
+			case PROXY_SOCKS4:
+			case PROXY_SOCKS4A:
+			case PROXY_SOCKS5:
+			case PROXY_HTTP:
+				proxyhost = space;
+				if(space && (space = strchr(space, ' ')))
+					*space++ = 0, proxyport = space;
+				if(space && (space = strchr(space, ' ')))
+					*space++ = 0, proxyuser = space;
+				if(space && (space = strchr(space, ' ')))
+					*space++ = 0, proxypass = space;
+				if(!proxyhost || !*proxyhost || !proxyport || !*proxyport) {
+					logger(LOG_ERR, "Host and port argument expected for proxy!");
+					free(proxy);
+					return false;
+				}
+				proxyhost = xstrdup(proxyhost);
+				proxyport = xstrdup(proxyport);
+				if(proxyuser && *proxyuser)
+					proxyuser = xstrdup(proxyuser);
+				if(proxypass && *proxypass)
+					proxypass = xstrdup(proxypass);
+				break;
+		}
+
+		free(proxy);
+	}
+
 	/* Read in all the subnets specified in the host configuration file */
 
 	cfg = lookup_config(config_tree, "Subnet");
@@ -355,6 +502,7 @@ static bool setup_myself(void) {
 	get_config_bool(lookup_config(config_tree, "DirectOnly"), &directonly);
 	get_config_bool(lookup_config(config_tree, "StrictSubnets"), &strictsubnets);
 	get_config_bool(lookup_config(config_tree, "TunnelServer"), &tunnelserver);
+	get_config_bool(lookup_config(config_tree, "LocalDiscovery"), &localdiscovery);
 	strictsubnets |= tunnelserver;
 
 	if(get_config_string(lookup_config(config_tree, "Mode"), &mode)) {
@@ -366,6 +514,7 @@ static bool setup_myself(void) {
 			routing_mode = RMODE_HUB;
 		else {
 			logger(LOG_ERR, "Invalid routing mode!");
+			free(mode);
 			return false;
 		}
 		free(mode);
@@ -380,6 +529,7 @@ static bool setup_myself(void) {
 			forwarding_mode = FMODE_KERNEL;
 		else {
 			logger(LOG_ERR, "Invalid forwarding mode!");
+			free(mode);
 			return false;
 		}
 		free(mode);
@@ -396,10 +546,30 @@ static bool setup_myself(void) {
 		myself->options |= OPTION_CLAMP_MSS;
 
 	get_config_bool(lookup_config(config_tree, "PriorityInheritance"), &priorityinheritance);
+	get_config_bool(lookup_config(config_tree, "DecrementTTL"), &decrement_ttl);
+	if(get_config_string(lookup_config(config_tree, "Broadcast"), &mode)) {
+		if(!strcasecmp(mode, "no"))
+			broadcast_mode = BMODE_NONE;
+		else if(!strcasecmp(mode, "yes") || !strcasecmp(mode, "mst"))
+			broadcast_mode = BMODE_MST;
+		else if(!strcasecmp(mode, "direct"))
+			broadcast_mode = BMODE_DIRECT;
+		else {
+			logger(LOG_ERR, "Invalid broadcast mode!");
+			free(mode);
+			return false;
+		}
+		free(mode);
+	}
 
 #if !defined(SOL_IP) || !defined(IP_TOS)
 	if(priorityinheritance)
-		logger(LOG_WARNING, "%s not supported on this platform", "PriorityInheritance");
+		logger(LOG_WARNING, "%s not supported on this platform for IPv4 connection", "PriorityInheritance");
+#endif
+
+#if !defined(IPPROTO_IPV6) || !defined(IPV6_TCLASS)
+	if(priorityinheritance)
+		logger(LOG_WARNING, "%s not supported on this platform for IPv6 connection", "PriorityInheritance");
 #endif
 
 	if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
@@ -413,6 +583,18 @@ static bool setup_myself(void) {
 	} else
 		maxtimeout = 900;
 
+	if(get_config_int(lookup_config(config_tree, "MinTimeout"), &mintimeout)) {
+			if(mintimeout < 0) {
+				logger(LOG_ERR, "Bogus minimum timeout!");
+				return false;
+			}
+			if(mintimeout > maxtimeout) {
+				logger(LOG_WARNING, "Minimum timeout (%d s) cannot be larger than maximum timeout (%d s). Correcting !", mintimeout, maxtimeout );
+				mintimeout=maxtimeout;
+			}
+		} else
+			mintimeout = 0;
+
 	if(get_config_int(lookup_config(config_tree, "UDPRcvBuf"), &udp_rcvbuf)) {
 		if(udp_rcvbuf <= 0) {
 			logger(LOG_ERR, "UDPRcvBuf cannot be negative!");
@@ -444,6 +626,7 @@ static bool setup_myself(void) {
 			addressfamily = AF_UNSPEC;
 		else {
 			logger(LOG_ERR, "Invalid address family!");
+			free(afname);
 			return false;
 		}
 		free(afname);
@@ -453,8 +636,7 @@ static bool setup_myself(void) {
 
 	/* Generate packet encryption key */
 
-	if(get_config_string
-	   (lookup_config(config_tree, "Cipher"), &cipher)) {
+	if(get_config_string(lookup_config(config_tree, "Cipher"), &cipher)) {
 		if(!strcasecmp(cipher, "none")) {
 			myself->incipher = NULL;
 		} else {
@@ -462,18 +644,31 @@ static bool setup_myself(void) {
 
 			if(!myself->incipher) {
 				logger(LOG_ERR, "Unrecognized cipher type!");
+				free(cipher);
 				return false;
 			}
 		}
+		free(cipher);
 	} else
-		myself->incipher = EVP_bf_cbc();
+		myself->incipher = EVP_aes_256_cbc();
 
 	if(myself->incipher)
-		myself->inkeylength = myself->incipher->key_len + myself->incipher->iv_len;
+		myself->inkeylength = EVP_CIPHER_key_length(myself->incipher) + EVP_CIPHER_iv_length(myself->incipher);
 	else
 		myself->inkeylength = 1;
 
-	myself->connection->outcipher = EVP_bf_ofb();
+	/* We need to use a stream mode for the meta protocol. Use AES for this,
+	   but try to match the key size with the one from the cipher selected
+	   by Cipher.
+	*/
+
+	int keylen = EVP_CIPHER_key_length(myself->incipher);
+	if(keylen <= 16)
+		myself->connection->outcipher = EVP_aes_128_cfb();
+	else if(keylen <= 24)
+		myself->connection->outcipher = EVP_aes_192_cfb();
+	else
+		myself->connection->outcipher = EVP_aes_256_cfb();
 
 	if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
 		keylifetime = 3600;
@@ -490,17 +685,20 @@ static bool setup_myself(void) {
 
 			if(!myself->indigest) {
 				logger(LOG_ERR, "Unrecognized digest type!");
+				free(digest);
 				return false;
 			}
 		}
+
+		free(digest);
 	} else
-		myself->indigest = EVP_sha1();
+		myself->indigest = EVP_sha256();
 
-	myself->connection->outdigest = EVP_sha1();
+	myself->connection->outdigest = EVP_sha256();
 
 	if(get_config_int(lookup_config(config_tree, "MACLength"), &myself->inmaclength)) {
 		if(myself->indigest) {
-			if(myself->inmaclength > myself->indigest->md_size) {
+			if(myself->inmaclength > EVP_MD_size(myself->indigest)) {
 				logger(LOG_ERR, "MAC length exceeds size of digest!");
 				return false;
 			} else if(myself->inmaclength < 0) {
@@ -539,7 +737,27 @@ static bool setup_myself(void) {
 
 	/* Open device */
 
-	if(!setup_device())
+	devops = os_devops;
+
+	if(get_config_string(lookup_config(config_tree, "DeviceType"), &type)) {
+		if(!strcasecmp(type, "dummy"))
+			devops = dummy_devops;
+		else if(!strcasecmp(type, "raw_socket"))
+			devops = raw_socket_devops;
+		else if(!strcasecmp(type, "multicast"))
+			devops = multicast_devops;
+#ifdef ENABLE_UML
+		else if(!strcasecmp(type, "uml"))
+			devops = uml_devops;
+#endif
+#ifdef ENABLE_VDE
+		else if(!strcasecmp(type, "vde"))
+			devops = vde_devops;
+#endif
+		free(type);
+	}
+
+	if(!devops.setup())
 		return false;
 
 	/* Run tinc-up script to further initialize the tap interface */
@@ -547,11 +765,16 @@ static bool setup_myself(void) {
 	xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 	xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 	xasprintf(&envp[3], "NAME=%s", myself->name);
-	envp[4] = NULL;
 
+#ifdef HAVE_MINGW
+	Sleep(1000);
+#endif
+#ifdef HAVE_CYGWIN
+	sleep(1);
+#endif
 	execute_script("tinc-up", envp);
 
-	for(i = 0; i < 5; i++)
+	for(i = 0; i < 4; i++)
 		free(envp[i]);
 
 	/* Run subnet-up scripts for our own subnets */
@@ -560,55 +783,138 @@ static bool setup_myself(void) {
 
 	/* Open sockets */
 
-	get_config_string(lookup_config(config_tree, "BindToAddress"), &address);
-
-	hint.ai_family = addressfamily;
-	hint.ai_socktype = SOCK_STREAM;
-	hint.ai_protocol = IPPROTO_TCP;
-	hint.ai_flags = AI_PASSIVE;
+	if(!do_detach && getenv("LISTEN_FDS")) {
+		sockaddr_t sa;
+		socklen_t salen;
 
-	err = getaddrinfo(address, myport, &hint, &ai);
+		listen_sockets = atoi(getenv("LISTEN_FDS"));
+#ifdef HAVE_UNSETENV
+		unsetenv("LISTEN_FDS");
+#endif
 
-	if(err || !ai) {
-		logger(LOG_ERR, "System call `%s' failed: %s", "getaddrinfo",
-			   gai_strerror(err));
-		return false;
-	}
+		if(listen_sockets > MAXSOCKETS) {
+			logger(LOG_ERR, "Too many listening sockets");
+			return false;
+		}
 
-	listen_sockets = 0;
+		for(i = 0; i < listen_sockets; i++) {
+			salen = sizeof sa;
+			if(getsockname(i + 3, &sa.sa, &salen) < 0) {
+				logger(LOG_ERR, "Could not get address of listen fd %d: %s", i + 3, sockstrerror(errno));
+				return false;
+			}
 
-	for(aip = ai; aip; aip = aip->ai_next) {
-		listen_socket[listen_sockets].tcp =
-			setup_listen_socket((sockaddr_t *) aip->ai_addr);
+			listen_socket[i].tcp = i + 3;
 
-		if(listen_socket[listen_sockets].tcp < 0)
-			continue;
+#ifdef FD_CLOEXEC
+		        fcntl(i + 3, F_SETFD, FD_CLOEXEC);
+#endif
 
-		listen_socket[listen_sockets].udp =
-			setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
+			listen_socket[i].udp = setup_vpn_in_socket(&sa);
+			if(listen_socket[i].udp < 0)
+				return false;
 
-		if(listen_socket[listen_sockets].udp < 0)
-			continue;
+			ifdebug(CONNECTIONS) {
+				hostname = sockaddr2hostname(&sa);
+				logger(LOG_NOTICE, "Listening on %s", hostname);
+				free(hostname);
+			}
 
-		ifdebug(CONNECTIONS) {
-			hostname = sockaddr2hostname((sockaddr_t *) aip->ai_addr);
-			logger(LOG_NOTICE, "Listening on %s", hostname);
-			free(hostname);
+			memcpy(&listen_socket[i].sa, &sa, salen);
 		}
+	} else {
+		listen_sockets = 0;
+		cfg = lookup_config(config_tree, "BindToAddress");
+
+		do {
+			get_config_string(cfg, &address);
+			if(cfg)
+				cfg = lookup_config_next(config_tree, cfg);
+
+			char *port = myport;
+
+			if(address) {
+				char *space = strchr(address, ' ');
+				if(space) {
+					*space++ = 0;
+					port = space;
+				}
+
+				if(!strcmp(address, "*"))
+					*address = 0;
+			}
 
-		memcpy(&listen_socket[listen_sockets].sa, aip->ai_addr, aip->ai_addrlen);
-		listen_sockets++;
-	}
+			hint.ai_family = addressfamily;
+			hint.ai_socktype = SOCK_STREAM;
+			hint.ai_protocol = IPPROTO_TCP;
+			hint.ai_flags = AI_PASSIVE;
 
-	freeaddrinfo(ai);
+#if HAVE_DECL_RES_INIT
+			// ensure glibc reloads /etc/resolv.conf.
+			res_init();
+#endif
+			err = getaddrinfo(address && *address ? address : NULL, port, &hint, &ai);
+			free(address);
+
+			if(err || !ai) {
+				logger(LOG_ERR, "System call `%s' failed: %s", "getaddrinfo",
+					   gai_strerror(err));
+				return false;
+			}
 
-	if(listen_sockets)
-		logger(LOG_NOTICE, "Ready");
-	else {
+			for(aip = ai; aip; aip = aip->ai_next) {
+				if(listen_sockets >= MAXSOCKETS) {
+					logger(LOG_ERR, "Too many listening sockets");
+					return false;
+				}
+
+				listen_socket[listen_sockets].tcp =
+					setup_listen_socket((sockaddr_t *) aip->ai_addr);
+
+				if(listen_socket[listen_sockets].tcp < 0)
+					continue;
+
+				listen_socket[listen_sockets].udp =
+					setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
+
+				if(listen_socket[listen_sockets].udp < 0)
+					continue;
+
+				ifdebug(CONNECTIONS) {
+					hostname = sockaddr2hostname((sockaddr_t *) aip->ai_addr);
+					logger(LOG_NOTICE, "Listening on %s", hostname);
+					free(hostname);
+				}
+
+				memcpy(&listen_socket[listen_sockets].sa, aip->ai_addr, aip->ai_addrlen);
+				listen_sockets++;
+			}
+
+			freeaddrinfo(ai);
+		} while(cfg);
+	}
+
+	if(!listen_sockets) {
 		logger(LOG_ERR, "Unable to create any listening socket!");
 		return false;
 	}
 
+	/* If no Port option was specified, set myport to the port used by the first listening socket. */
+
+	if(!port_specified) {
+		sockaddr_t sa;
+		socklen_t salen = sizeof sa;
+		if(!getsockname(listen_socket[0].udp, &sa.sa, &salen)) {
+			free(myport);
+			sockaddr2str(&sa, NULL, &myport);
+			if(!myport)
+				myport = xstrdup("655");
+		}
+	}
+
+	/* Done. */
+
+	logger(LOG_NOTICE, "Ready");
 	return true;
 }
 
@@ -652,7 +958,7 @@ bool setup_network(void) {
 void close_network_connections(void) {
 	avl_node_t *node, *next;
 	connection_t *c;
-	char *envp[5];
+	char *envp[5] = {NULL};
 	int i;
 
 	for(node = connection_tree->head; node; node = next) {
@@ -686,7 +992,6 @@ void close_network_connections(void) {
 	xasprintf(&envp[1], "DEVICE=%s", device ? : "");
 	xasprintf(&envp[2], "INTERFACE=%s", iface ? : "");
 	xasprintf(&envp[3], "NAME=%s", myself->name);
-	envp[4] = NULL;
 
 	exit_requests();
 	exit_edges();
@@ -702,7 +1007,7 @@ void close_network_connections(void) {
 	for(i = 0; i < 4; i++)
 		free(envp[i]);
 
-	close_device();
+	devops.close();
 
 	return;
 }