X-Git-Url: https://www.tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fnet_setup.c;h=7b4c741f0fe55ce1bd5daefcf39e2d990fa8867e;hb=refs%2Fheads%2F1.1;hp=6becfbb405ac29c400c92247bd281a7e41cc6c33;hpb=5cbef906209eb5005f821af8f55a6f5d7e7d060c;p=tinc

diff --git a/src/net_setup.c b/src/net_setup.c
index 6becfbb4..dd6c58f1 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,
-                  2000-2017 Guus Sliepen <guus@tinc-vpn.org>
+                  2000-2021 Guus Sliepen <guus@tinc-vpn.org>
                   2006      Scott Lamb <slamb@slamb.org>
                   2010      Brandon Black <blblack@gmail.com>
 
@@ -23,9 +23,12 @@
 #include "system.h"
 
 #include "cipher.h"
+#include "conf_net.h"
 #include "conf.h"
 #include "connection.h"
+#include "compression.h"
 #include "control.h"
+#include "crypto.h"
 #include "device.h"
 #include "digest.h"
 #include "ecdsa.h"
@@ -37,25 +40,27 @@
 #include "process.h"
 #include "protocol.h"
 #include "route.h"
-#include "rsa.h"
 #include "script.h"
 #include "subnet.h"
 #include "utils.h"
 #include "xalloc.h"
+#include "keys.h"
+#include "sandbox.h"
 
 #ifdef HAVE_MINIUPNPC
 #include "upnp.h"
 #endif
 
-char *myport;
+ports_t myport;
 static io_t device_io;
 devops_t devops;
 bool device_standby = false;
 
-char *proxyhost;
-char *proxyport;
-char *proxyuser;
-char *proxypass;
+char *proxyhost = NULL;
+char *proxyport = NULL;
+char *proxyuser = NULL;
+char *proxypass = NULL;
+
 proxytype_t proxytype;
 bool autoconnect;
 bool disablebuggypeers;
@@ -64,21 +69,24 @@ char *scriptinterpreter;
 char *scriptextension;
 
 bool node_read_ecdsa_public_key(node_t *n) {
-	if(ecdsa_active(n->ecdsa))
+	if(ecdsa_active(n->ecdsa)) {
 		return true;
+	}
 
-	splay_tree_t *config_tree;
 	FILE *fp;
 	char *pubname = NULL;
 	char *p;
 
-	init_configuration(&config_tree);
-	if(!read_host_config(config_tree, n->name))
+	splay_tree_t config;
+	init_configuration(&config);
+
+	if(!read_host_config(&config, n->name, true)) {
 		goto exit;
+	}
 
 	/* First, check for simple Ed25519PublicKey statement */
 
-	if(get_config_string(lookup_config(config_tree, "Ed25519PublicKey"), &p)) {
+	if(get_config_string(lookup_config(&config, "Ed25519PublicKey"), &p)) {
 		n->ecdsa = ecdsa_set_base64_public_key(p);
 		free(p);
 		goto exit;
@@ -86,147 +94,25 @@ bool node_read_ecdsa_public_key(node_t *n) {
 
 	/* Else, check for Ed25519PublicKeyFile statement and read it */
 
-	if(!get_config_string(lookup_config(config_tree, "Ed25519PublicKeyFile"), &pubname))
+	if(!get_config_string(lookup_config(&config, "Ed25519PublicKeyFile"), &pubname)) {
 		xasprintf(&pubname, "%s" SLASH "hosts" SLASH "%s", confbase, n->name);
+	}
 
 	fp = fopen(pubname, "r");
 
-	if(!fp)
+	if(!fp) {
 		goto exit;
+	}
 
 	n->ecdsa = ecdsa_read_pem_public_key(fp);
 	fclose(fp);
 
 exit:
-	exit_configuration(&config_tree);
+	splay_empty_tree(&config);
 	free(pubname);
 	return n->ecdsa;
 }
 
-bool read_ecdsa_public_key(connection_t *c) {
-	if(ecdsa_active(c->ecdsa))
-		return true;
-
-	FILE *fp;
-	char *fname;
-	char *p;
-
-	if(!c->config_tree) {
-		init_configuration(&c->config_tree);
-		if(!read_host_config(c->config_tree, c->name))
-			return false;
-	}
-
-	/* First, check for simple Ed25519PublicKey statement */
-
-	if(get_config_string(lookup_config(c->config_tree, "Ed25519PublicKey"), &p)) {
-		c->ecdsa = ecdsa_set_base64_public_key(p);
-		free(p);
-		return c->ecdsa;
-	}
-
-	/* Else, check for Ed25519PublicKeyFile statement and read it */
-
-	if(!get_config_string(lookup_config(c->config_tree, "Ed25519PublicKeyFile"), &fname))
-		xasprintf(&fname, "%s" SLASH "hosts" SLASH "%s", confbase, c->name);
-
-	fp = fopen(fname, "r");
-
-	if(!fp) {
-		logger(DEBUG_ALWAYS, LOG_ERR, "Error reading Ed25519 public key file `%s': %s",
-			   fname, strerror(errno));
-		free(fname);
-		return false;
-	}
-
-	c->ecdsa = ecdsa_read_pem_public_key(fp);
-
-	if(!c->ecdsa && errno != ENOENT)
-		logger(DEBUG_ALWAYS, LOG_ERR, "Parsing Ed25519 public key file `%s' failed.", fname);
-
-	fclose(fp);
-	free(fname);
-	return c->ecdsa;
-}
-
-#ifndef DISABLE_LEGACY
-bool read_rsa_public_key(connection_t *c) {
-	FILE *fp;
-	char *fname;
-	char *n;
-
-	/* First, check for simple PublicKey statement */
-
-	if(get_config_string(lookup_config(c->config_tree, "PublicKey"), &n)) {
-		c->rsa = rsa_set_hex_public_key(n, "FFFF");
-		free(n);
-		return c->rsa;
-	}
-
-	/* Else, check for PublicKeyFile statement and read it */
-
-	if(!get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &fname))
-		xasprintf(&fname, "%s" SLASH "hosts" SLASH "%s", confbase, c->name);
-
-	fp = fopen(fname, "r");
-
-	if(!fp) {
-		logger(DEBUG_ALWAYS, LOG_ERR, "Error reading RSA public key file `%s': %s", fname, strerror(errno));
-		free(fname);
-		return false;
-	}
-
-	c->rsa = rsa_read_pem_public_key(fp);
-	fclose(fp);
-
-	if(!c->rsa)
-		logger(DEBUG_ALWAYS, LOG_ERR, "Reading RSA public key file `%s' failed: %s", fname, strerror(errno));
-	free(fname);
-	return c->rsa;
-}
-#endif
-
-static bool read_ecdsa_private_key(void) {
-	FILE *fp;
-	char *fname;
-
-	/* Check for PrivateKeyFile statement and read it */
-
-	if(!get_config_string(lookup_config(config_tree, "Ed25519PrivateKeyFile"), &fname))
-		xasprintf(&fname, "%s" SLASH "ed25519_key.priv", confbase);
-
-	fp = fopen(fname, "r");
-
-	if(!fp) {
-		logger(DEBUG_ALWAYS, LOG_ERR, "Error reading Ed25519 private key file `%s': %s", fname, strerror(errno));
-		if(errno == ENOENT)
-			logger(DEBUG_ALWAYS, LOG_INFO, "Create an Ed25519 keypair with `tinc -n %s generate-ed25519-keys'.", netname ?: ".");
-		free(fname);
-		return false;
-	}
-
-#if !defined(HAVE_MINGW) && !defined(HAVE_CYGWIN)
-	struct stat s;
-
-	if(fstat(fileno(fp), &s)) {
-		logger(DEBUG_ALWAYS, LOG_ERR, "Could not stat Ed25519 private key file `%s': %s'", fname, strerror(errno));
-		free(fname);
-		return false;
-	}
-
-	if(s.st_mode & ~0100700)
-		logger(DEBUG_ALWAYS, LOG_WARNING, "Warning: insecure file permissions for Ed25519 private key file `%s'!", fname);
-#endif
-
-	myself->connection->ecdsa = ecdsa_read_pem_private_key(fp);
-	fclose(fp);
-
-	if(!myself->connection->ecdsa)
-		logger(DEBUG_ALWAYS, LOG_ERR, "Reading Ed25519 private key file `%s' failed", fname);
-	free(fname);
-	return myself->connection->ecdsa;
-}
-
 static bool read_invitation_key(void) {
 	FILE *fp;
 	char fname[PATH_MAX];
@@ -236,91 +122,40 @@ static bool read_invitation_key(void) {
 		invitation_key = NULL;
 	}
 
-	snprintf(fname, sizeof fname, "%s" SLASH "invitations" SLASH "ed25519_key.priv", confbase);
+	snprintf(fname, sizeof(fname), "%s" SLASH "invitations" SLASH "ed25519_key.priv", confbase);
 
 	fp = fopen(fname, "r");
 
 	if(fp) {
 		invitation_key = ecdsa_read_pem_private_key(fp);
 		fclose(fp);
-		if(!invitation_key)
+
+		if(!invitation_key) {
 			logger(DEBUG_ALWAYS, LOG_ERR, "Reading Ed25519 private key file `%s' failed", fname);
+		}
 	}
 
 	return invitation_key;
 }
 
 #ifndef DISABLE_LEGACY
-static bool read_rsa_private_key(void) {
-	FILE *fp;
-	char *fname;
-	char *n, *d;
-
-	/* First, check for simple PrivateKey statement */
-
-	if(get_config_string(lookup_config(config_tree, "PrivateKey"), &d)) {
-		if(!get_config_string(lookup_config(config_tree, "PublicKey"), &n)) {
-			logger(DEBUG_ALWAYS, LOG_ERR, "PrivateKey used but no PublicKey found!");
-			free(d);
-			return false;
-		}
-		myself->connection->rsa = rsa_set_hex_private_key(n, "FFFF", d);
-		free(n);
-		free(d);
-		return myself->connection->rsa;
-	}
-
-	/* Else, check for PrivateKeyFile statement and read it */
-
-	if(!get_config_string(lookup_config(config_tree, "PrivateKeyFile"), &fname))
-		xasprintf(&fname, "%s" SLASH "rsa_key.priv", confbase);
-
-	fp = fopen(fname, "r");
-
-	if(!fp) {
-		logger(DEBUG_ALWAYS, LOG_ERR, "Error reading RSA private key file `%s': %s",
-			   fname, strerror(errno));
-		if(errno == ENOENT)
-			logger(DEBUG_ALWAYS, LOG_INFO, "Create an RSA keypair with `tinc -n %s generate-rsa-keys'.", netname ?: ".");
-		free(fname);
-		return false;
-	}
-
-#if !defined(HAVE_MINGW) && !defined(HAVE_CYGWIN)
-	struct stat s;
-
-	if(fstat(fileno(fp), &s)) {
-		logger(DEBUG_ALWAYS, LOG_ERR, "Could not stat RSA private key file `%s': %s'", fname, strerror(errno));
-		free(fname);
-		return false;
-	}
-
-	if(s.st_mode & ~0100700)
-		logger(DEBUG_ALWAYS, LOG_WARNING, "Warning: insecure file permissions for RSA private key file `%s'!", fname);
-#endif
-
-	myself->connection->rsa = rsa_read_pem_private_key(fp);
-	fclose(fp);
-
-	if(!myself->connection->rsa)
-		logger(DEBUG_ALWAYS, LOG_ERR, "Reading RSA private key file `%s' failed: %s", fname, strerror(errno));
-	free(fname);
-	return myself->connection->rsa;
-}
-#endif
-
 static timeout_t keyexpire_timeout;
 
 static void keyexpire_handler(void *data) {
 	regenerate_key();
-	timeout_set(data, &(struct timeval){keylifetime, rand() % 100000});
+	timeout_set(data, &(struct timeval) {
+		keylifetime, jitter()
+	});
 }
+#endif
 
 void regenerate_key(void) {
 	logger(DEBUG_STATUS, LOG_INFO, "Expiring symmetric keys");
 	send_key_changed();
-	for splay_each(node_t, n, node_tree)
+
+	for splay_each(node_t, n, &node_tree) {
 		n->status.validkey_in = false;
+	}
 }
 
 void load_all_nodes(void) {
@@ -328,36 +163,38 @@ void load_all_nodes(void) {
 	struct dirent *ent;
 	char dname[PATH_MAX];
 
-	snprintf(dname, sizeof dname, "%s" SLASH "hosts", confbase);
+	snprintf(dname, sizeof(dname), "%s" SLASH "hosts", confbase);
 	dir = opendir(dname);
+
 	if(!dir) {
 		logger(DEBUG_ALWAYS, LOG_ERR, "Could not open %s: %s", dname, strerror(errno));
 		return;
 	}
 
 	while((ent = readdir(dir))) {
-		if(!check_id(ent->d_name))
+		if(!check_id(ent->d_name)) {
 			continue;
+		}
 
 		node_t *n = lookup_node(ent->d_name);
 
-		splay_tree_t *config_tree;
-		init_configuration(&config_tree);
-		read_config_options(config_tree, ent->d_name);
-		read_host_config(config_tree, ent->d_name);
+		splay_tree_t config;
+		init_configuration(&config);
+		read_config_options(&config, ent->d_name);
+		read_host_config(&config, ent->d_name, true);
 
 		if(!n) {
-			n = new_node();
-			n->name = xstrdup(ent->d_name);
+			n = new_node(ent->d_name);
 			node_add(n);
 		}
 
 		if(strictsubnets) {
-			for(config_t *cfg = lookup_config(config_tree, "Subnet"); cfg; cfg = lookup_config_next(config_tree, cfg)) {
+			for(config_t *cfg = lookup_config(&config, "Subnet"); cfg; cfg = lookup_config_next(&config, cfg)) {
 				subnet_t *s, *s2;
 
-				if(!get_config_subnet(cfg, &s))
+				if(!get_config_subnet(cfg, &s)) {
 					continue;
+				}
 
 				if((s2 = lookup_subnet(n, s))) {
 					s2->expires = -1;
@@ -368,10 +205,11 @@ void load_all_nodes(void) {
 			}
 		}
 
-		if(lookup_config(config_tree, "Address"))
+		if(lookup_config(&config, "Address")) {
 			n->status.has_address = true;
+		}
 
-		exit_configuration(&config_tree);
+		splay_empty_tree(&config);
 	}
 
 	closedir(dir);
@@ -381,38 +219,53 @@ char *get_name(void) {
 	char *name = NULL;
 	char *returned_name;
 
-	get_config_string(lookup_config(config_tree, "Name"), &name);
+	get_config_string(lookup_config(&config_tree, "Name"), &name);
 
-	if(!name)
+	if(!name) {
 		return NULL;
+	}
 
 	returned_name = replace_name(name);
 	free(name);
 	return returned_name;
 }
 
-bool setup_myself_reloadable(void) {
-	char *proxy = NULL;
-	char *rmode = NULL;
-	char *fmode = NULL;
-	char *bmode = NULL;
-	char *afname = NULL;
-	char *space;
-	bool choice;
+static void read_interpreter(void) {
+	char *interpreter = NULL;
+	get_config_string(lookup_config(&config_tree, "ScriptsInterpreter"), &interpreter);
 
-	free(scriptinterpreter);
-	scriptinterpreter = NULL;
-	get_config_string(lookup_config(config_tree, "ScriptsInterpreter"), &scriptinterpreter);
+	if(!interpreter || (sandbox_can(START_PROCESSES, AFTER_SANDBOX) && sandbox_can(USE_NEW_PATHS, AFTER_SANDBOX))) {
+		free(scriptinterpreter);
+		scriptinterpreter = interpreter;
+		return;
+	}
+
+	if(!string_eq(interpreter, scriptinterpreter)) {
+		logger(DEBUG_ALWAYS, LOG_NOTICE, "Not changing ScriptsInterpreter because of sandbox.");
+	}
 
+	free(interpreter);
+}
+
+bool setup_myself_reloadable(void) {
+	read_interpreter();
 
 	free(scriptextension);
-	if(!get_config_string(lookup_config(config_tree, "ScriptsExtension"), &scriptextension))
+
+	if(!get_config_string(lookup_config(&config_tree, "ScriptsExtension"), &scriptextension)) {
 		scriptextension = xstrdup("");
+	}
+
+	char *proxy = NULL;
+
+	get_config_string(lookup_config(&config_tree, "Proxy"), &proxy);
 
-	get_config_string(lookup_config(config_tree, "Proxy"), &proxy);
 	if(proxy) {
-		if((space = strchr(proxy, ' ')))
+		char *space;
+
+		if((space = strchr(proxy, ' '))) {
 			*space++ = 0;
+		}
 
 		if(!strcasecmp(proxy, "none")) {
 			proxytype = PROXY_NONE;
@@ -425,224 +278,380 @@ bool setup_myself_reloadable(void) {
 		} else if(!strcasecmp(proxy, "http")) {
 			proxytype = PROXY_HTTP;
 		} else if(!strcasecmp(proxy, "exec")) {
-			proxytype = PROXY_EXEC;
+			if(sandbox_can(START_PROCESSES, AFTER_SANDBOX)) {
+				proxytype = PROXY_EXEC;
+			} else {
+				logger(DEBUG_ALWAYS, LOG_ERR, "Cannot use exec proxies with current sandbox level.");
+				return false;
+			}
 		} else {
 			logger(DEBUG_ALWAYS, LOG_ERR, "Unknown proxy type %s!", proxy);
+			free_string(proxy);
 			return false;
 		}
 
+		free(proxyhost);
+		proxyhost = NULL;
+
+		free(proxyport);
+		proxyport = NULL;
+
+		free_string(proxyuser);
+		proxyuser = NULL;
+
+		free_string(proxypass);
+		proxypass = NULL;
+
 		switch(proxytype) {
-			case PROXY_NONE:
-			default:
-				break;
+		case PROXY_NONE:
+		default:
+			break;
+
+		case PROXY_EXEC:
+			if(!space || !*space) {
+				logger(DEBUG_ALWAYS, LOG_ERR, "Argument expected for proxy type exec!");
+				free_string(proxy);
+				return false;
+			}
 
-			case PROXY_EXEC:
-				if(!space || !*space) {
-					logger(DEBUG_ALWAYS, LOG_ERR, "Argument expected for proxy type exec!");
-					return false;
-				}
-				proxyhost =  xstrdup(space);
-				break;
+			if(!sandbox_can(USE_NEW_PATHS, AFTER_SANDBOX)) {
+				logger(DEBUG_ALWAYS, LOG_NOTICE, "Changed exec proxy may fail to work because of sandbox.");
+			}
 
-			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(DEBUG_ALWAYS, LOG_ERR, "Host and port argument expected for proxy!");
-					return false;
-				}
-				proxyhost = xstrdup(proxyhost);
-				proxyport = xstrdup(proxyport);
-				if(proxyuser && *proxyuser)
-					proxyuser = xstrdup(proxyuser);
-				if(proxypass && *proxypass)
-					proxypass = xstrdup(proxypass);
-				break;
+			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(!proxyhost || !*proxyhost || !proxyport || !*proxyport) {
+				logger(DEBUG_ALWAYS, LOG_ERR, "Host and port argument expected for proxy!");
+				proxyport = NULL;
+				proxyhost = NULL;
+				free_string(proxy);
+				return false;
+			}
+
+			if(space && (space = strchr(space, ' '))) {
+				*space++ = 0, proxyuser = space;
+			}
+
+			if(space && (space = strchr(space, ' '))) {
+				*space++ = 0, proxypass = space;
+			}
+
+			proxyhost = xstrdup(proxyhost);
+			proxyport = xstrdup(proxyport);
+
+			if(proxyuser && *proxyuser) {
+				proxyuser = xstrdup(proxyuser);
+			}
+
+			if(proxypass && *proxypass) {
+				proxypass = xstrdup(proxypass);
+			}
+
+			break;
 		}
 
-		free(proxy);
+		free_string(proxy);
 	}
 
-	if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice) && choice)
+	bool choice;
+
+	if(get_config_bool(lookup_config(&config_tree, "IndirectData"), &choice) && choice) {
 		myself->options |= OPTION_INDIRECT;
+	}
 
-	if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice) && choice)
+	if(get_config_bool(lookup_config(&config_tree, "TCPOnly"), &choice) && choice) {
 		myself->options |= OPTION_TCPONLY;
+	}
 
-	if(myself->options & OPTION_TCPONLY)
+	if(myself->options & OPTION_TCPONLY) {
 		myself->options |= OPTION_INDIRECT;
+	}
+
+	get_config_bool(lookup_config(&config_tree, "UDPDiscovery"), &udp_discovery);
+	get_config_int(lookup_config(&config_tree, "UDPDiscoveryKeepaliveInterval"), &udp_discovery_keepalive_interval);
+	get_config_int(lookup_config(&config_tree, "UDPDiscoveryInterval"), &udp_discovery_interval);
+	get_config_int(lookup_config(&config_tree, "UDPDiscoveryTimeout"), &udp_discovery_timeout);
 
-	get_config_bool(lookup_config(config_tree, "UDPDiscovery"), &udp_discovery);
-	get_config_int(lookup_config(config_tree, "UDPDiscoveryKeepaliveInterval"), &udp_discovery_keepalive_interval);
-	get_config_int(lookup_config(config_tree, "UDPDiscoveryInterval"), &udp_discovery_interval);
-	get_config_int(lookup_config(config_tree, "UDPDiscoveryTimeout"), &udp_discovery_timeout);
+	get_config_int(lookup_config(&config_tree, "MTUInfoInterval"), &mtu_info_interval);
+	get_config_int(lookup_config(&config_tree, "UDPInfoInterval"), &udp_info_interval);
 
-	get_config_int(lookup_config(config_tree, "MTUInfoInterval"), &mtu_info_interval);
-	get_config_int(lookup_config(config_tree, "UDPInfoInterval"), &udp_info_interval);
+	get_config_bool(lookup_config(&config_tree, "DirectOnly"), &directonly);
+	get_config_bool(lookup_config(&config_tree, "LocalDiscovery"), &localdiscovery);
 
-	get_config_bool(lookup_config(config_tree, "DirectOnly"), &directonly);
-	get_config_bool(lookup_config(config_tree, "LocalDiscovery"), &localdiscovery);
+	char *rmode = NULL;
 
-	if(get_config_string(lookup_config(config_tree, "Mode"), &rmode)) {
-		if(!strcasecmp(rmode, "router"))
+	if(get_config_string(lookup_config(&config_tree, "Mode"), &rmode)) {
+		if(!strcasecmp(rmode, "router")) {
 			routing_mode = RMODE_ROUTER;
-		else if(!strcasecmp(rmode, "switch"))
+		} else if(!strcasecmp(rmode, "switch")) {
 			routing_mode = RMODE_SWITCH;
-		else if(!strcasecmp(rmode, "hub"))
+		} else if(!strcasecmp(rmode, "hub")) {
 			routing_mode = RMODE_HUB;
-		else {
+		} else {
 			logger(DEBUG_ALWAYS, LOG_ERR, "Invalid routing mode!");
+			free(rmode);
 			return false;
 		}
+
 		free(rmode);
 	}
 
-	if(get_config_string(lookup_config(config_tree, "Forwarding"), &fmode)) {
-		if(!strcasecmp(fmode, "off"))
+	char *fmode = NULL;
+
+	if(get_config_string(lookup_config(&config_tree, "Forwarding"), &fmode)) {
+		if(!strcasecmp(fmode, "off")) {
 			forwarding_mode = FMODE_OFF;
-		else if(!strcasecmp(fmode, "internal"))
+		} else if(!strcasecmp(fmode, "internal")) {
 			forwarding_mode = FMODE_INTERNAL;
-		else if(!strcasecmp(fmode, "kernel"))
+		} else if(!strcasecmp(fmode, "kernel")) {
 			forwarding_mode = FMODE_KERNEL;
-		else {
+		} else {
 			logger(DEBUG_ALWAYS, LOG_ERR, "Invalid forwarding mode!");
+			free(fmode);
 			return false;
 		}
+
 		free(fmode);
 	}
 
-	choice = true;
-	get_config_bool(lookup_config(config_tree, "PMTUDiscovery"), &choice);
-	if(choice)
+	choice = !(myself->options & OPTION_TCPONLY);
+	get_config_bool(lookup_config(&config_tree, "PMTUDiscovery"), &choice);
+
+	if(choice) {
 		myself->options |= OPTION_PMTU_DISCOVERY;
+	}
 
 	choice = true;
-	get_config_bool(lookup_config(config_tree, "ClampMSS"), &choice);
-	if(choice)
+	get_config_bool(lookup_config(&config_tree, "ClampMSS"), &choice);
+
+	if(choice) {
 		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"), &bmode)) {
-		if(!strcasecmp(bmode, "no"))
+	get_config_bool(lookup_config(&config_tree, "PriorityInheritance"), &priorityinheritance);
+	get_config_bool(lookup_config(&config_tree, "DecrementTTL"), &decrement_ttl);
+
+	char *bmode = NULL;
+
+	if(get_config_string(lookup_config(&config_tree, "Broadcast"), &bmode)) {
+		if(!strcasecmp(bmode, "no")) {
 			broadcast_mode = BMODE_NONE;
-		else if(!strcasecmp(bmode, "yes") || !strcasecmp(bmode, "mst"))
+		} else if(!strcasecmp(bmode, "yes") || !strcasecmp(bmode, "mst")) {
 			broadcast_mode = BMODE_MST;
-		else if(!strcasecmp(bmode, "direct"))
+		} else if(!strcasecmp(bmode, "direct")) {
 			broadcast_mode = BMODE_DIRECT;
-		else {
+		} else {
 			logger(DEBUG_ALWAYS, LOG_ERR, "Invalid broadcast mode!");
+			free(bmode);
 			return false;
 		}
+
 		free(bmode);
 	}
 
-	const char* const DEFAULT_BROADCAST_SUBNETS[] = { "ff:ff:ff:ff:ff:ff", "255.255.255.255", "224.0.0.0/4", "ff00::/8" };
-	for (size_t i = 0; i < sizeof(DEFAULT_BROADCAST_SUBNETS) / sizeof(*DEFAULT_BROADCAST_SUBNETS); i++) {
+	/* Delete all broadcast subnets before re-adding them */
+
+	for splay_each(subnet_t, s, &subnet_tree) {
+		if(!s->owner) {
+			splay_delete_node(&subnet_tree, node);
+		}
+	}
+
+	const char *const DEFAULT_BROADCAST_SUBNETS[] = { "ff:ff:ff:ff:ff:ff", "255.255.255.255", "224.0.0.0/4", "ff00::/8" };
+
+	for(size_t i = 0; i < sizeof(DEFAULT_BROADCAST_SUBNETS) / sizeof(*DEFAULT_BROADCAST_SUBNETS); i++) {
 		subnet_t *s = new_subnet();
-		if (!str2net(s, DEFAULT_BROADCAST_SUBNETS[i]))
+
+		if(!str2net(s, DEFAULT_BROADCAST_SUBNETS[i])) {
 			abort();
+		}
+
 		subnet_add(NULL, s);
 	}
-	for (config_t* cfg = lookup_config(config_tree, "BroadcastSubnet"); cfg; cfg = lookup_config_next(config_tree, cfg)) {
+
+	for(config_t *cfg = lookup_config(&config_tree, "BroadcastSubnet"); cfg; cfg = lookup_config_next(&config_tree, cfg)) {
 		subnet_t *s;
-		if (!get_config_subnet(cfg, &s))
+
+		if(!get_config_subnet(cfg, &s)) {
 			continue;
+		}
+
 		subnet_add(NULL, s);
 	}
 
-#if !defined(IPPROTO_IP) || !defined(IP_TOS)
-	if(priorityinheritance)
+#if !defined(IP_TOS)
+
+	if(priorityinheritance) {
 		logger(DEBUG_ALWAYS, LOG_WARNING, "%s not supported on this platform for IPv4 connections", "PriorityInheritance");
+	}
+
 #endif
 
-#if !defined(IPPROTO_IPV6) || !defined(IPV6_TCLASS)
-	if(priorityinheritance)
+#if !defined(IPV6_TCLASS)
+
+	if(priorityinheritance) {
 		logger(DEBUG_ALWAYS, LOG_WARNING, "%s not supported on this platform for IPv6 connections", "PriorityInheritance");
+	}
+
 #endif
 
-	if(!get_config_int(lookup_config(config_tree, "MACExpire"), &macexpire))
+	if(!get_config_int(lookup_config(&config_tree, "MACExpire"), &macexpire)) {
 		macexpire = 600;
+	}
 
-	if(get_config_int(lookup_config(config_tree, "MaxTimeout"), &maxtimeout)) {
+	if(get_config_int(lookup_config(&config_tree, "MaxTimeout"), &maxtimeout)) {
 		if(maxtimeout <= 0) {
 			logger(DEBUG_ALWAYS, LOG_ERR, "Bogus maximum timeout!");
 			return false;
 		}
-	} else
+	} else {
 		maxtimeout = 900;
+	}
+
+	char *afname = NULL;
 
-	if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname)) {
-		if(!strcasecmp(afname, "IPv4"))
+	if(get_config_string(lookup_config(&config_tree, "AddressFamily"), &afname)) {
+		if(!strcasecmp(afname, "IPv4")) {
 			addressfamily = AF_INET;
-		else if(!strcasecmp(afname, "IPv6"))
+		} else if(!strcasecmp(afname, "IPv6")) {
 			addressfamily = AF_INET6;
-		else if(!strcasecmp(afname, "any"))
+		} else if(!strcasecmp(afname, "any")) {
 			addressfamily = AF_UNSPEC;
-		else {
+		} else {
 			logger(DEBUG_ALWAYS, LOG_ERR, "Invalid address family!");
+			free(afname);
 			return false;
 		}
+
 		free(afname);
 	}
 
-	get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
+	get_config_bool(lookup_config(&config_tree, "Hostnames"), &hostnames);
 
-	if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
+	if(!get_config_int(lookup_config(&config_tree, "KeyExpire"), &keylifetime)) {
 		keylifetime = 3600;
+	}
 
-	config_t *cfg = lookup_config(config_tree, "AutoConnect");
-	if(cfg) {
-		if(!get_config_bool(cfg, &autoconnect)) {
-			// Some backwards compatibility with when this option was an int
-			int val = 0;
-			get_config_int(cfg, &val);
-			autoconnect = val;
-		}
+	if(!get_config_bool(lookup_config(&config_tree, "AutoConnect"), &autoconnect)) {
+		autoconnect = true;
 	}
 
-	get_config_bool(lookup_config(config_tree, "DisableBuggyPeers"), &disablebuggypeers);
+	get_config_bool(lookup_config(&config_tree, "DisableBuggyPeers"), &disablebuggypeers);
+
+	if(!get_config_int(lookup_config(&config_tree, "InvitationExpire"), &invitation_lifetime)) {
+		invitation_lifetime = 604800;        // 1 week
+	}
 
 	read_invitation_key();
 
 	return true;
 }
 
+// Get the port that `from_fd` is listening on, and assign it to
+// `sa` if `sa` has a dynamically allocated (zero) port.
+static bool assign_static_port(sockaddr_t *sa, int from_fd) {
+	// We cannot get a port from a bad FD. Bail out.
+	if(from_fd <= 0) {
+		return false;
+	}
+
+	int port = get_bound_port(from_fd);
+
+	if(!port) {
+		return false;
+	}
+
+	// If the port is non-zero, don't reassign it as it's already static.
+	switch(sa->sa.sa_family) {
+	case AF_INET:
+		if(!sa->in.sin_port) {
+			sa->in.sin_port = htons(port);
+		}
+
+		return true;
+
+	case AF_INET6:
+		if(!sa->in6.sin6_port) {
+			sa->in6.sin6_port = htons(port);
+		}
+
+		return true;
+
+	default:
+		logger(DEBUG_ALWAYS, LOG_ERR, "Unknown address family 0x%x", sa->sa.sa_family);
+		return false;
+	}
+}
+
+typedef int (*bind_fn_t)(const sockaddr_t *);
+
+static int bind_reusing_port(const sockaddr_t *sa, int from_fd, bind_fn_t setup) {
+	sockaddr_t reuse_sa;
+	memcpy(&reuse_sa, sa, SALEN(sa->sa));
+
+	int fd = -1;
+
+	// Check if the address we've been passed here is using port 0.
+	// If it is, try to get an actual port from an already bound socket, and reuse it here.
+	if(assign_static_port(&reuse_sa, from_fd)) {
+		fd = setup(&reuse_sa);
+	}
+
+	// If we're binding to a hardcoded non-zero port, or no socket is listening yet,
+	// or binding failed, try the original address.
+	if(fd < 0) {
+		fd = setup(sa);
+	}
+
+	return fd;
+}
+
 /*
   Add listening sockets.
 */
 static bool add_listen_address(char *address, bool bindto) {
-	char *port = myport;
+	char *port = myport.tcp;
 
 	if(address) {
 		char *space = strchr(address, ' ');
+
 		if(space) {
 			*space++ = 0;
 			port = space;
 		}
 
-		if(!strcmp(address, "*"))
+		if(!strcmp(address, "*")) {
 			*address = 0;
+		}
 	}
 
 	struct addrinfo *ai, hint = {0};
+
 	hint.ai_family = addressfamily;
+
 	hint.ai_socktype = SOCK_STREAM;
+
 	hint.ai_protocol = IPPROTO_TCP;
+
 	hint.ai_flags = AI_PASSIVE;
 
 #if HAVE_DECL_RES_INIT
 	res_init();
+
 #endif
 	int err = getaddrinfo(address && *address ? address : NULL, port, &hint, &ai);
+
 	free(address);
 
 	if(err || !ai) {
@@ -660,37 +669,56 @@ static bool add_listen_address(char *address, bool bindto) {
 				break;
 			}
 
-		if(found)
+		if(found) {
 			continue;
+		}
 
 		if(listen_sockets >= MAXSOCKETS) {
+			listen_sockets = MAXSOCKETS;
 			logger(DEBUG_ALWAYS, LOG_ERR, "Too many listening sockets");
+			freeaddrinfo(ai);
 			return false;
 		}
 
-		int tcp_fd = setup_listen_socket((sockaddr_t *) aip->ai_addr);
+		const sockaddr_t *sa = (sockaddr_t *) aip->ai_addr;
+		int from_fd = listen_socket[0].tcp.fd;
+
+		// If we're binding to a dynamically allocated (zero) port, try to get the actual
+		// port of the first TCP socket, and use it for this one. If that succeeds, our
+		// tincd instance will use the same port for all addresses it listens on.
+		int tcp_fd = bind_reusing_port(sa, from_fd, setup_listen_socket);
 
-		if(tcp_fd < 0)
+		if(tcp_fd < 0) {
 			continue;
+		}
+
+		// If we just successfully bound the first socket, use it for the UDP procedure below.
+		// Otherwise, keep using the socket we've obtained from listen_socket[0].
+		if(!from_fd) {
+			from_fd = tcp_fd;
+		}
 
-		int udp_fd = setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
+		int udp_fd = bind_reusing_port(sa, from_fd, setup_vpn_in_socket);
 
 		if(udp_fd < 0) {
-			close(tcp_fd);
+			closesocket(tcp_fd);
 			continue;
 		}
 
-		io_add(&listen_socket[listen_sockets].tcp, handle_new_meta_connection, &listen_socket[listen_sockets], tcp_fd, IO_READ);
-		io_add(&listen_socket[listen_sockets].udp, handle_incoming_vpn_data, &listen_socket[listen_sockets], udp_fd, IO_READ);
+		listen_socket_t *sock = &listen_socket[listen_sockets];
+		io_add(&sock->tcp, handle_new_meta_connection, sock, tcp_fd, IO_READ);
+		io_add(&sock->udp, handle_incoming_vpn_data, sock, udp_fd, IO_READ);
 
 		if(debug_level >= DEBUG_CONNECTIONS) {
-			char *hostname = sockaddr2hostname((sockaddr_t *) aip->ai_addr);
-			logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Listening on %s", hostname);
+			int tcp_port = get_bound_port(tcp_fd);
+			char *hostname = NULL;
+			sockaddr2str(sa, &hostname, NULL);
+			logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Listening on %s port %d", hostname, tcp_port);
 			free(hostname);
 		}
 
-		listen_socket[listen_sockets].bindto = bindto;
-		memcpy(&listen_socket[listen_sockets].sa, aip->ai_addr, aip->ai_addrlen);
+		sock->bindto = bindto;
+		memcpy(&sock->sa, aip->ai_addr, aip->ai_addrlen);
 		listen_sockets++;
 	}
 
@@ -699,8 +727,9 @@ static bool add_listen_address(char *address, bool bindto) {
 }
 
 void device_enable(void) {
-	if (devops.enable)
+	if(devops.enable) {
 		devops.enable();
+	}
 
 	/* Run tinc-up script to further initialize the tap interface */
 
@@ -716,15 +745,16 @@ void device_disable(void) {
 	execute_script("tinc-down", &env);
 	environment_exit(&env);
 
-	if (devops.disable)
+	if(devops.disable) {
 		devops.disable();
+	}
 }
 
 /*
   Configure node_t myself and set up the local sockets (listen only)
 */
 static bool setup_myself(void) {
-	char *name, *hostname, *cipher, *digest, *type;
+	char *name, *type;
 	char *address = NULL;
 	bool port_specified = false;
 
@@ -734,16 +764,18 @@ static bool setup_myself(void) {
 	}
 
 	myname = xstrdup(name);
-	myself = new_node();
+	myself = new_node(name);
 	myself->connection = new_connection();
-	myself->name = name;
-	myself->connection->name = xstrdup(name);
-	read_host_config(config_tree, name);
+	myself->connection->name = name;
+	read_host_config(&config_tree, name, true);
 
-	if(!get_config_string(lookup_config(config_tree, "Port"), &myport))
-		myport = xstrdup("655");
-	else
+	if(!get_config_string(lookup_config(&config_tree, "Port"), &myport.tcp)) {
+		myport.tcp = xstrdup("655");
+	} else {
 		port_specified = true;
+	}
+
+	myport.udp = xstrdup(myport.tcp);
 
 	myself->connection->options = 0;
 	myself->connection->protocol_major = PROT_MAJOR;
@@ -752,22 +784,38 @@ static bool setup_myself(void) {
 	myself->options |= PROT_MINOR << 24;
 
 #ifdef DISABLE_LEGACY
-	experimental = read_ecdsa_private_key();
+	myself->connection->ecdsa = read_ecdsa_private_key(&config_tree, NULL);
+	experimental = myself->connection->ecdsa != NULL;
+
 	if(!experimental) {
 		logger(DEBUG_ALWAYS, LOG_ERR, "No private key available, cannot start tinc!");
 		return false;
 	}
+
 #else
-	if(!get_config_bool(lookup_config(config_tree, "ExperimentalProtocol"), &experimental)) {
-		experimental = read_ecdsa_private_key();
-		if(!experimental)
+
+	if(!get_config_bool(lookup_config(&config_tree, "ExperimentalProtocol"), &experimental)) {
+		myself->connection->ecdsa = read_ecdsa_private_key(&config_tree, NULL);
+		experimental = myself->connection->ecdsa != NULL;
+
+		if(!experimental) {
 			logger(DEBUG_ALWAYS, LOG_WARNING, "Support for SPTPS disabled.");
+		}
 	} else {
-		if(experimental && !read_ecdsa_private_key())
-			return false;
+		if(experimental) {
+			myself->connection->ecdsa = read_ecdsa_private_key(&config_tree, NULL);
+
+			if(!myself->connection->ecdsa) {
+				return false;
+			}
+		}
 	}
 
-	if(!read_rsa_private_key()) {
+	rsa_t *rsa = read_rsa_private_key(&config_tree, NULL);
+
+	if(rsa) {
+		myself->connection->legacy = new_legacy_ctx(rsa);
+	} else {
 		if(experimental) {
 			logger(DEBUG_ALWAYS, LOG_WARNING, "Support for legacy protocol disabled.");
 		} else {
@@ -775,67 +823,89 @@ static bool setup_myself(void) {
 			return false;
 		}
 	}
+
 #endif
 
 	/* Ensure myport is numeric */
+	if(!is_decimal(myport.tcp)) {
+		uint16_t port = service_to_port(myport.tcp);
 
-	if(!atoi(myport)) {
-		struct addrinfo *ai = str2addrinfo("localhost", myport, SOCK_DGRAM);
-		sockaddr_t sa;
-		if(!ai || !ai->ai_addr)
+		if(!port) {
 			return false;
-		free(myport);
-		memcpy(&sa, ai->ai_addr, ai->ai_addrlen);
-		sockaddr2str(&sa, NULL, &myport);
+		}
+
+		free(myport.tcp);
+		myport.tcp = int_to_str(port);
+
+		free(myport.udp);
+		myport.udp = xstrdup(myport.tcp);
 	}
 
 	/* Read in all the subnets specified in the host configuration file */
 
-	for(config_t *cfg = lookup_config(config_tree, "Subnet"); cfg; cfg = lookup_config_next(config_tree, cfg)) {
+	for(config_t *cfg = lookup_config(&config_tree, "Subnet"); cfg; cfg = lookup_config_next(&config_tree, cfg)) {
 		subnet_t *subnet;
 
-		if(!get_config_subnet(cfg, &subnet))
+		if(!get_config_subnet(cfg, &subnet)) {
 			return false;
+		}
 
 		subnet_add(myself, subnet);
 	}
 
 	/* Check some options */
 
-	if(!setup_myself_reloadable())
+	if(!setup_myself_reloadable()) {
 		return false;
+	}
 
-	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, "StrictSubnets"), &strictsubnets);
+	get_config_bool(lookup_config(&config_tree, "TunnelServer"), &tunnelserver);
 	strictsubnets |= tunnelserver;
 
-	if(get_config_int(lookup_config(config_tree, "MaxConnectionBurst"), &max_connection_burst)) {
+	if(get_config_int(lookup_config(&config_tree, "MaxConnectionBurst"), &max_connection_burst)) {
 		if(max_connection_burst <= 0) {
 			logger(DEBUG_ALWAYS, LOG_ERR, "MaxConnectionBurst cannot be negative!");
 			return false;
 		}
 	}
 
-	if(get_config_int(lookup_config(config_tree, "UDPRcvBuf"), &udp_rcvbuf)) {
+	if(get_config_int(lookup_config(&config_tree, "UDPRcvBuf"), &udp_rcvbuf)) {
 		if(udp_rcvbuf < 0) {
 			logger(DEBUG_ALWAYS, LOG_ERR, "UDPRcvBuf cannot be negative!");
 			return false;
 		}
+
+		udp_rcvbuf_warnings = true;
 	}
 
-	if(get_config_int(lookup_config(config_tree, "UDPSndBuf"), &udp_sndbuf)) {
+	if(get_config_int(lookup_config(&config_tree, "UDPSndBuf"), &udp_sndbuf)) {
 		if(udp_sndbuf < 0) {
 			logger(DEBUG_ALWAYS, LOG_ERR, "UDPSndBuf cannot be negative!");
 			return false;
 		}
+
+		udp_sndbuf_warnings = true;
+	}
+
+	get_config_int(lookup_config(&config_tree, "FWMark"), &fwmark);
+#ifndef SO_MARK
+
+	if(fwmark) {
+		logger(DEBUG_ALWAYS, LOG_ERR, "FWMark not supported on this platform!");
+		return false;
 	}
 
+#endif
+
 	int replaywin_int;
-	if(get_config_int(lookup_config(config_tree, "ReplayWindow"), &replaywin_int)) {
+
+	if(get_config_int(lookup_config(&config_tree, "ReplayWindow"), &replaywin_int)) {
 		if(replaywin_int < 0) {
 			logger(DEBUG_ALWAYS, LOG_ERR, "ReplayWindow cannot be negative!");
 			return false;
 		}
+
 		replaywin = (unsigned)replaywin_int;
 		sptps_replaywin = replaywin;
 	}
@@ -843,54 +913,119 @@ static bool setup_myself(void) {
 #ifndef DISABLE_LEGACY
 	/* Generate packet encryption key */
 
-	if(!get_config_string(lookup_config(config_tree, "Cipher"), &cipher))
+	char *cipher;
+
+	if(!get_config_string(lookup_config(&config_tree, "Cipher"), &cipher)) {
 		cipher = xstrdup("aes-256-cbc");
+	}
 
 	if(!strcasecmp(cipher, "none")) {
 		myself->incipher = NULL;
-	} else if(!(myself->incipher = cipher_open_by_name(cipher))) {
-		logger(DEBUG_ALWAYS, LOG_ERR, "Unrecognized cipher type!");
-		return false;
+	} else {
+		myself->incipher = cipher_alloc();
+
+		if(!cipher_open_by_name(myself->incipher, cipher)) {
+			logger(DEBUG_ALWAYS, LOG_ERR, "Unrecognized cipher type!");
+			cipher_free(myself->incipher);
+			myself->incipher = NULL;
+			free(cipher);
+			return false;
+		}
 	}
 
 	free(cipher);
 
-	timeout_add(&keyexpire_timeout, keyexpire_handler, &keyexpire_timeout, &(struct timeval){keylifetime, rand() % 100000});
+	timeout_add(&keyexpire_timeout, keyexpire_handler, &keyexpire_timeout, &(struct timeval) {
+		keylifetime, jitter()
+	});
 
 	/* Check if we want to use message authentication codes... */
 
 	int maclength = 4;
-	get_config_int(lookup_config(config_tree, "MACLength"), &maclength);
+	get_config_int(lookup_config(&config_tree, "MACLength"), &maclength);
 
 	if(maclength < 0) {
 		logger(DEBUG_ALWAYS, LOG_ERR, "Bogus MAC length!");
 		return false;
 	}
 
-	if(!get_config_string(lookup_config(config_tree, "Digest"), &digest))
+	char *digest;
+
+	if(!get_config_string(lookup_config(&config_tree, "Digest"), &digest)) {
 		digest = xstrdup("sha256");
+	}
 
 	if(!strcasecmp(digest, "none")) {
 		myself->indigest = NULL;
-	} else if(!(myself->indigest = digest_open_by_name(digest, maclength))) {
-		logger(DEBUG_ALWAYS, LOG_ERR, "Unrecognized digest type!");
-		return false;
+	} else {
+		myself->indigest = digest_alloc();
+
+		if(!digest_open_by_name(myself->indigest, digest, maclength)) {
+			logger(DEBUG_ALWAYS, LOG_ERR, "Unrecognized digest type!");
+			digest_free(myself->indigest);
+			myself->indigest = NULL;
+			free(digest);
+			return false;
+		}
 	}
 
 	free(digest);
 #endif
 
 	/* Compression */
+	int incompression = 0;
+
+	if(get_config_int(lookup_config(&config_tree, "Compression"), &incompression)) {
+		myself->incompression = incompression;
 
-	if(get_config_int(lookup_config(config_tree, "Compression"), &myself->incompression)) {
-		if(myself->incompression < 0 || myself->incompression > 11) {
+		switch(myself->incompression) {
+		case COMPRESS_LZ4:
+#ifdef HAVE_LZ4
+			break;
+#else
 			logger(DEBUG_ALWAYS, LOG_ERR, "Bogus compression level!");
+			logger(DEBUG_ALWAYS, LOG_ERR, "LZ4 compression is unavailable on this node.");
 			return false;
-		}
-	} else
-		myself->incompression = 0;
+#endif
 
-	myself->connection->outcompression = 0;
+		case COMPRESS_LZO_HI:
+		case COMPRESS_LZO_LO:
+#ifdef HAVE_LZO
+			break;
+#else
+			logger(DEBUG_ALWAYS, LOG_ERR, "Bogus compression level!");
+			logger(DEBUG_ALWAYS, LOG_ERR, "LZO compression is unavailable on this node.");
+			return false;
+#endif
+
+		case COMPRESS_ZLIB_9:
+		case COMPRESS_ZLIB_8:
+		case COMPRESS_ZLIB_7:
+		case COMPRESS_ZLIB_6:
+		case COMPRESS_ZLIB_5:
+		case COMPRESS_ZLIB_4:
+		case COMPRESS_ZLIB_3:
+		case COMPRESS_ZLIB_2:
+		case COMPRESS_ZLIB_1:
+#ifdef HAVE_ZLIB
+			break;
+#else
+			logger(DEBUG_ALWAYS, LOG_ERR, "Bogus compression level!");
+			logger(DEBUG_ALWAYS, LOG_ERR, "ZLIB compression is unavailable on this node.");
+			return false;
+#endif
+
+		case COMPRESS_NONE:
+			break;
+
+		default:
+			logger(DEBUG_ALWAYS, LOG_ERR, "Bogus compression level!");
+			logger(DEBUG_ALWAYS, LOG_ERR, "Compression level %i is unrecognized by this node.", myself->incompression);
+			return false;
+		}
+	} else {
+		myself->incompression = COMPRESS_NONE;
+	}
 
 	/* Done */
 
@@ -909,70 +1044,89 @@ static bool setup_myself(void) {
 
 	devops = os_devops;
 
-	if(get_config_string(lookup_config(config_tree, "DeviceType"), &type)) {
-		if(!strcasecmp(type, "dummy"))
+	if(get_config_string(lookup_config(&config_tree, "DeviceType"), &type)) {
+		if(!strcasecmp(type, DEVICE_DUMMY)) {
 			devops = dummy_devops;
-		else if(!strcasecmp(type, "raw_socket"))
+		} else if(!strcasecmp(type, "raw_socket")) {
 			devops = raw_socket_devops;
-		else if(!strcasecmp(type, "multicast"))
+		} else if(!strcasecmp(type, "multicast")) {
 			devops = multicast_devops;
-		else if(!strcasecmp(type, "fd"))
+		}
+
+#ifdef HAVE_SYS_UN_H
+		else if(!strcasecmp(type, "fd")) {
 			devops = fd_devops;
+		}
+
+#endif
 #ifdef ENABLE_UML
-		else if(!strcasecmp(type, "uml"))
+		else if(!strcasecmp(type, "uml")) {
 			devops = uml_devops;
+		}
+
 #endif
 #ifdef ENABLE_VDE
-		else if(!strcasecmp(type, "vde"))
+		else if(!strcasecmp(type, "vde")) {
 			devops = vde_devops;
+		}
+
 #endif
 		free(type);
 	}
 
-	get_config_bool(lookup_config(config_tree, "DeviceStandby"), &device_standby);
+	get_config_bool(lookup_config(&config_tree, "DeviceStandby"), &device_standby);
 
-	if(!devops.setup())
+	if(!devops.setup()) {
 		return false;
+	}
 
-	if(device_fd >= 0)
+	if(device_fd >= 0) {
 		io_add(&device_io, handle_device_data, NULL, device_fd, IO_READ);
+	}
 
 	/* Open sockets */
 
-	if(!do_detach && getenv("LISTEN_FDS")) {
+	const char *listen_fds = getenv("LISTEN_FDS");
+
+	if(!do_detach && listen_fds) {
 		sockaddr_t sa;
 		socklen_t salen;
 
-		listen_sockets = atoi(getenv("LISTEN_FDS"));
+		listen_sockets = atoi(listen_fds);
 #ifdef HAVE_UNSETENV
 		unsetenv("LISTEN_FDS");
 #endif
 
 		if(listen_sockets > MAXSOCKETS) {
+			listen_sockets = MAXSOCKETS;
 			logger(DEBUG_ALWAYS, LOG_ERR, "Too many listening sockets");
 			return false;
 		}
 
 		for(int i = 0; i < listen_sockets; i++) {
-			salen = sizeof sa;
-			if(getsockname(i + 3, &sa.sa, &salen) < 0) {
-				logger(DEBUG_ALWAYS, LOG_ERR, "Could not get address of listen fd %d: %s", i + 3, sockstrerror(sockerrno));
+			const int tcp_fd = i + 3;
+			salen = sizeof(sa);
+
+			if(getsockname(tcp_fd, &sa.sa, &salen) < 0) {
+				logger(DEBUG_ALWAYS, LOG_ERR, "Could not get address of listen fd %d: %s", tcp_fd, sockstrerror(sockerrno));
 				return false;
 			}
 
 #ifdef FD_CLOEXEC
-			fcntl(i + 3, F_SETFD, FD_CLOEXEC);
+			fcntl(tcp_fd, F_SETFD, FD_CLOEXEC);
 #endif
 
 			int udp_fd = setup_vpn_in_socket(&sa);
-			if(udp_fd < 0)
+
+			if(udp_fd < 0) {
 				return false;
+			}
 
-			io_add(&listen_socket[i].tcp, (io_cb_t)handle_new_meta_connection, &listen_socket[i], i + 3, IO_READ);
+			io_add(&listen_socket[i].tcp, (io_cb_t)handle_new_meta_connection, &listen_socket[i], tcp_fd, IO_READ);
 			io_add(&listen_socket[i].udp, (io_cb_t)handle_incoming_vpn_data, &listen_socket[i], udp_fd, IO_READ);
 
 			if(debug_level >= DEBUG_CONNECTIONS) {
-				hostname = sockaddr2hostname(&sa);
+				char *hostname = sockaddr2hostname(&sa);
 				logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Listening on %s", hostname);
 				free(hostname);
 			}
@@ -983,23 +1137,28 @@ static bool setup_myself(void) {
 		listen_sockets = 0;
 		int cfgs = 0;
 
-		for(config_t *cfg = lookup_config(config_tree, "BindToAddress"); cfg; cfg = lookup_config_next(config_tree, cfg)) {
+		for(config_t *cfg = lookup_config(&config_tree, "BindToAddress"); cfg; cfg = lookup_config_next(&config_tree, cfg)) {
 			cfgs++;
 			get_config_string(cfg, &address);
-			if(!add_listen_address(address, true))
+
+			if(!add_listen_address(address, true)) {
 				return false;
+			}
 		}
 
-		for(config_t *cfg = lookup_config(config_tree, "ListenAddress"); cfg; cfg = lookup_config_next(config_tree, cfg)) {
+		for(config_t *cfg = lookup_config(&config_tree, "ListenAddress"); cfg; cfg = lookup_config_next(&config_tree, cfg)) {
 			cfgs++;
 			get_config_string(cfg, &address);
-			if(!add_listen_address(address, false))
+
+			if(!add_listen_address(address, false)) {
 				return false;
+			}
 		}
 
 		if(!cfgs)
-			if(!add_listen_address(address, NULL))
+			if(!add_listen_address(address, NULL)) {
 				return false;
+			}
 	}
 
 	if(!listen_sockets) {
@@ -1009,32 +1168,37 @@ static bool setup_myself(void) {
 
 	/* If no Port option was specified, set myport to the port used by the first listening socket. */
 
-	if(!port_specified || atoi(myport) == 0) {
-		sockaddr_t sa;
-		socklen_t salen = sizeof sa;
-		if(!getsockname(listen_socket[0].udp.fd, &sa.sa, &salen)) {
-			free(myport);
-			sockaddr2str(&sa, NULL, &myport);
-			if(!myport)
-				myport = xstrdup("655");
-		}
+	if(!port_specified || atoi(myport.tcp) == 0) {
+		listen_socket_t *sock = &listen_socket[0];
+
+		uint16_t tcp = get_bound_port(sock->tcp.fd);
+		free(myport.tcp);
+		myport.tcp = int_to_str(tcp);
+
+		uint16_t udp = get_bound_port(sock->udp.fd);
+		free(myport.udp);
+		myport.udp = int_to_str(udp);
 	}
 
-	xasprintf(&myself->hostname, "MYSELF port %s", myport);
+	xasprintf(&myself->hostname, "MYSELF port %s", myport.tcp);
 	myself->connection->hostname = xstrdup(myself->hostname);
 
 	char *upnp = NULL;
-	get_config_string(lookup_config(config_tree, "UPnP"), &upnp);
+	get_config_string(lookup_config(&config_tree, "UPnP"), &upnp);
 	bool upnp_tcp = false;
 	bool upnp_udp = false;
-	if (upnp) {
-		if (!strcasecmp(upnp, "yes"))
+
+	if(upnp) {
+		if(!strcasecmp(upnp, "yes")) {
 			upnp_tcp = upnp_udp = true;
-		else if (!strcasecmp(upnp, "udponly"))
+		} else if(!strcasecmp(upnp, "udponly")) {
 			upnp_udp = true;
+		}
+
 		free(upnp);
 	}
-	if (upnp_tcp || upnp_udp) {
+
+	if(upnp_tcp || upnp_udp) {
 #ifdef HAVE_MINIUPNPC
 		upnp_init(upnp_tcp, upnp_udp);
 #else
@@ -1055,33 +1219,38 @@ static bool setup_myself(void) {
 bool setup_network(void) {
 	init_connections();
 	init_subnets();
-	init_nodes();
-	init_edges();
-	init_requests();
 
-	if(get_config_int(lookup_config(config_tree, "PingInterval"), &pinginterval)) {
+	if(get_config_int(lookup_config(&config_tree, "PingInterval"), &pinginterval)) {
 		if(pinginterval < 1) {
 			pinginterval = 86400;
 		}
-	} else
+	} else {
 		pinginterval = 60;
+	}
 
-	if(!get_config_int(lookup_config(config_tree, "PingTimeout"), &pingtimeout))
+	if(!get_config_int(lookup_config(&config_tree, "PingTimeout"), &pingtimeout)) {
 		pingtimeout = 5;
-	if(pingtimeout < 1 || pingtimeout > pinginterval)
+	}
+
+	if(pingtimeout < 1 || pingtimeout > pinginterval) {
 		pingtimeout = pinginterval;
+	}
 
-	if(!get_config_int(lookup_config(config_tree, "MaxOutputBufferSize"), &maxoutbufsize))
+	if(!get_config_int(lookup_config(&config_tree, "MaxOutputBufferSize"), &maxoutbufsize)) {
 		maxoutbufsize = 10 * MTU;
+	}
 
-	if(!setup_myself())
+	if(!setup_myself()) {
 		return false;
+	}
 
-	if(!init_control())
+	if(!init_control()) {
 		return false;
+	}
 
-	if (!device_standby)
+	if(!device_standby) {
 		device_enable();
+	}
 
 	/* Run subnet-up scripts for our own subnets */
 
@@ -1094,29 +1263,31 @@ bool setup_network(void) {
   close all open network connections
 */
 void close_network_connections(void) {
-	for(list_node_t *node = connection_list->head, *next; node; node = next) {
+	for(list_node_t *node = connection_list.head, *next; node; node = next) {
 		next = node->next;
 		connection_t *c = node->data;
+
 		/* Keep control connections open until the end, so they know when we really terminated */
-		if(c->status.control)
+		if(c->status.control) {
 			c->socket = -1;
+		}
+
 		c->outgoing = NULL;
 		terminate_connection(c, false);
 	}
 
-	if(outgoing_list)
-		list_delete_list(outgoing_list);
+	list_empty_list(&outgoing_list);
 
 	if(myself && myself->connection) {
 		subnet_update(myself, NULL, false);
-		connection_del(myself->connection);
+		free_connection(myself->connection);
 	}
 
 	for(int i = 0; i < listen_sockets; i++) {
 		io_del(&listen_socket[i].tcp);
 		io_del(&listen_socket[i].udp);
-		close(listen_socket[i].tcp.fd);
-		close(listen_socket[i].udp.fd);
+		closesocket(listen_socket[i].tcp.fd);
+		closesocket(listen_socket[i].udp.fd);
 	}
 
 	exit_requests();
@@ -1125,15 +1296,20 @@ void close_network_connections(void) {
 	exit_nodes();
 	exit_connections();
 
-	if (!device_standby)
+	if(!device_standby) {
 		device_disable();
+	}
 
-	free(myport);
+	free(myport.tcp);
+	free(myport.udp);
 
-	if (device_fd >= 0)
+	if(device_fd >= 0) {
 		io_del(&device_io);
-	if (devops.close)
+	}
+
+	if(devops.close) {
 		devops.close();
+	}
 
 	exit_control();