X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fprotocol_auth.c;h=385e54366dbd1bb4bad446446df0687503baf576;hp=fc0c3aae2bc7a2a9eed94d84461a41050e86ee10;hb=8794274a30d535d49636fec825a0afbf30d8010d;hpb=f75dcef72a81a337e847adf0bae54198894f65b9

diff --git a/src/protocol_auth.c b/src/protocol_auth.c
index fc0c3aae..385e5436 100644
--- a/src/protocol_auth.c
+++ b/src/protocol_auth.c
@@ -1,7 +1,7 @@
 /*
     protocol_auth.c -- handle the meta-protocol, authentication
-    Copyright (C) 1999-2002 Ivo Timmermans <ivo@o2w.nl>,
-                  2000-2002 Guus Sliepen <guus@sliepen.eu.org>
+    Copyright (C) 1999-2005 Ivo Timmermans,
+                  2000-2013 Guus Sliepen <guus@tinc-vpn.org>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -13,92 +13,164 @@
     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 program; if not, write to the Free Software
-    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-
-    $Id: protocol_auth.c,v 1.1.4.16 2002/09/09 21:24:45 guus Exp $
+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
 
-#include "config.h"
-
-#include <stdlib.h>
-#include <string.h>
-#include <syslog.h>
-#include <stdio.h>
-#include <stdarg.h>
-#include <errno.h>
-
-#include <utils.h>
-#include <xalloc.h>
-#include <avl_tree.h>
+#include "system.h"
 
 #include <openssl/sha.h>
 #include <openssl/rand.h>
+#include <openssl/err.h>
 #include <openssl/evp.h>
 
-#ifndef HAVE_RAND_PSEUDO_BYTES
-#define RAND_pseudo_bytes RAND_bytes
-#endif
-
+#include "avl_tree.h"
 #include "conf.h"
-#include "net.h"
-#include "netutl.h"
-#include "protocol.h"
-#include "meta.h"
 #include "connection.h"
-#include "node.h"
 #include "edge.h"
 #include "graph.h"
+#include "logger.h"
+#include "meta.h"
+#include "net.h"
+#include "netutl.h"
+#include "node.h"
+#include "protocol.h"
+#include "utils.h"
+#include "xalloc.h"
+
+static bool send_proxyrequest(connection_t *c) {
+	switch(proxytype) {
+		case PROXY_HTTP: {
+			char *host;
+			char *port;
+
+			sockaddr2str(&c->address, &host, &port);
+			send_request(c, "CONNECT %s:%s HTTP/1.1\r\n\r", host, port);
+			free(host);
+			free(port);
+			return true;
+		}
+		case PROXY_SOCKS4: {
+			if(c->address.sa.sa_family != AF_INET) {
+				logger(LOG_ERR, "Cannot connect to an IPv6 host through a SOCKS 4 proxy!");
+				return false;
+			}
+			char s4req[9 + (proxyuser ? strlen(proxyuser) : 0)];
+			s4req[0] = 4;
+			s4req[1] = 1;
+			memcpy(s4req + 2, &c->address.in.sin_port, 2);
+			memcpy(s4req + 4, &c->address.in.sin_addr, 4);
+			if(proxyuser)
+				strcpy(s4req + 8, proxyuser);
+			s4req[sizeof s4req - 1] = 0;
+			c->tcplen = 8;
+			return send_meta(c, s4req, sizeof s4req);
+		}
+		case PROXY_SOCKS5: {
+			int len = 3 + 6 + (c->address.sa.sa_family == AF_INET ? 4 : 16);
+			c->tcplen = 2;
+			if(proxypass)
+				len += 3 + strlen(proxyuser) + strlen(proxypass);
+			char s5req[len];
+			int i = 0;
+			s5req[i++] = 5;
+			s5req[i++] = 1;
+			if(proxypass) {
+				s5req[i++] = 2;
+				s5req[i++] = 1;
+				s5req[i++] = strlen(proxyuser);
+				strcpy(s5req + i, proxyuser);
+				i += strlen(proxyuser);
+				s5req[i++] = strlen(proxypass);
+				strcpy(s5req + i, proxypass);
+				i += strlen(proxypass);
+				c->tcplen += 2;
+			} else {
+				s5req[i++] = 0;
+			}
+			s5req[i++] = 5;
+			s5req[i++] = 1;
+			s5req[i++] = 0;
+			if(c->address.sa.sa_family == AF_INET) {
+				s5req[i++] = 1;
+				memcpy(s5req + i, &c->address.in.sin_addr, 4);
+				i += 4;
+				memcpy(s5req + i, &c->address.in.sin_port, 2);
+				i += 2;
+				c->tcplen += 10;
+			} else if(c->address.sa.sa_family == AF_INET6) {
+				s5req[i++] = 3;
+				memcpy(s5req + i, &c->address.in6.sin6_addr, 16);
+				i += 16;
+				memcpy(s5req + i, &c->address.in6.sin6_port, 2);
+				i += 2;
+				c->tcplen += 22;
+			} else {
+				logger(LOG_ERR, "Address family %hx not supported for SOCKS 5 proxies!", c->address.sa.sa_family);
+				return false;
+			}
+			if(i > len)
+				abort();
+			return send_meta(c, s5req, sizeof s5req);
+		}
+		case PROXY_SOCKS4A:
+			logger(LOG_ERR, "Proxy type not implemented yet");
+			return false;
+		case PROXY_EXEC:
+			return true;
+		default:
+			logger(LOG_ERR, "Unknown proxy type");
+			return false;
+	}
+}
 
-#include "system.h"
-
-int send_id(connection_t * c)
-{
-	cp();
+bool send_id(connection_t *c) {
+	if(proxytype && c->outgoing)
+		if(!send_proxyrequest(c))
+			return false;
 
 	return send_request(c, "%d %s %d", ID, myself->connection->name,
 						myself->connection->protocol_version);
 }
 
-int id_h(connection_t * c)
-{
+bool id_h(connection_t *c) {
 	char name[MAX_STRING_SIZE];
-	int bla;
-
-	cp();
 
 	if(sscanf(c->buffer, "%*d " MAX_STRING " %d", name, &c->protocol_version) != 2) {
-		syslog(LOG_ERR, _("Got bad %s from %s (%s)"), "ID", c->name,
+		logger(LOG_ERR, "Got bad %s from %s (%s)", "ID", c->name,
 			   c->hostname);
-		return -1;
+		return false;
 	}
 
 	/* Check if identity is a valid name */
 
-	if(check_id(name)) {
-		syslog(LOG_ERR, _("Got bad %s from %s (%s): %s"), "ID", c->name,
+	if(!check_id(name)) {
+		logger(LOG_ERR, "Got bad %s from %s (%s): %s", "ID", c->name,
 			   c->hostname, "invalid name");
-		return -1;
+		return false;
 	}
 
-	/* If we set c->name in advance, make sure we are connected to the right host */
+	/* If this is an outgoing connection, make sure we are connected to the right host */
 
-	if(c->name) {
+	if(c->outgoing) {
 		if(strcmp(c->name, name)) {
-			syslog(LOG_ERR, _("Peer %s is %s instead of %s"), c->hostname, name,
+			logger(LOG_ERR, "Peer %s is %s instead of %s", c->hostname, name,
 				   c->name);
-			return -1;
+			return false;
 		}
-	} else
+	} else {
+		if(c->name)
+			free(c->name);
 		c->name = xstrdup(name);
+	}
 
 	/* Check if version matches */
 
 	if(c->protocol_version != myself->connection->protocol_version) {
-		syslog(LOG_ERR, _("Peer %s (%s) uses incompatible version %d"),
+		logger(LOG_ERR, "Peer %s (%s) uses incompatible version %d",
 			   c->name, c->hostname, c->protocol_version);
-		return -1;
+		return false;
 	}
 
 	if(bypass_security) {
@@ -111,52 +183,39 @@ int id_h(connection_t * c)
 	if(!c->config_tree) {
 		init_configuration(&c->config_tree);
 
-		bla = read_connection_config(c);
-
-		if(bla) {
-			syslog(LOG_ERR, _("Peer %s had unknown identity (%s)"), c->hostname,
+		if(!read_connection_config(c)) {
+			logger(LOG_ERR, "Peer %s had unknown identity (%s)", c->hostname,
 				   c->name);
-			return -1;
+			return false;
 		}
 	}
 
-	if(read_rsa_public_key(c)) {
-		return -1;
+	if(!read_rsa_public_key(c)) {
+		return false;
 	}
 
-	/* Check some options */
-
-	if((get_config_bool(lookup_config(c->config_tree, "IndirectData"), &bla) && bla) || myself->options & OPTION_INDIRECT)
-		c->options |= OPTION_INDIRECT;
-
-	if((get_config_bool(lookup_config(c->config_tree, "TCPOnly"), &bla) && bla) || myself->options & OPTION_TCPONLY)
-		c->options |= OPTION_TCPONLY | OPTION_INDIRECT;
-
 	c->allow_request = METAKEY;
 
 	return send_metakey(c);
 }
 
-int send_metakey(connection_t * c)
-{
-	char buffer[MAX_STRING_SIZE];
-	int len, x;
-
-	cp();
+bool send_metakey(connection_t *c) {
+	bool x;
 
-	len = RSA_size(c->rsa_key);
+	int len = RSA_size(c->rsa_key);
 
 	/* Allocate buffers for the meta key */
 
-	if(!c->outkey)
-		c->outkey = xmalloc(len);
+	char buffer[2 * len + 1];
+	
+	c->outkey = xrealloc(c->outkey, len);
 
 	if(!c->outctx)
-		c->outctx = xmalloc(sizeof(*c->outctx));
-	cp();
+		c->outctx = xmalloc_and_zero(sizeof(*c->outctx));
+
 	/* Copy random data to the buffer */
 
-	RAND_bytes(c->outkey, len);
+	RAND_bytes((unsigned char *)c->outkey, len);
 
 	/* The message we send must be smaller than the modulus of the RSA key.
 	   By definition, for a key of k bits, the following formula holds:
@@ -170,10 +229,10 @@ int send_metakey(connection_t * c)
 
 	c->outkey[0] &= 0x7F;
 
-	if(debug_lvl >= DEBUG_SCARY_THINGS) {
+	ifdebug(SCARY_THINGS) {
 		bin2hex(c->outkey, buffer, len);
 		buffer[len * 2] = '\0';
-		syslog(LOG_DEBUG, _("Generated random meta key (unencrypted): %s"),
+		logger(LOG_DEBUG, "Generated random meta key (unencrypted): %s",
 			   buffer);
 	}
 
@@ -184,10 +243,10 @@ int send_metakey(connection_t * c)
 	   with a length equal to that of the modulus of the RSA key.
 	 */
 
-	if(RSA_public_encrypt(len, c->outkey, buffer, c->rsa_key, RSA_NO_PADDING) != len) {
-		syslog(LOG_ERR, _("Error during encryption of meta key for %s (%s)"),
-			   c->name, c->hostname);
-		return -1;
+	if(RSA_public_encrypt(len, (unsigned char *)c->outkey, (unsigned char *)buffer, c->rsa_key, RSA_NO_PADDING) != len) {
+		logger(LOG_ERR, "Error during encryption of meta key for %s (%s): %s",
+			   c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
+		return false;
 	}
 
 	/* Convert the encrypted random data to a hexadecimal formatted string */
@@ -205,31 +264,30 @@ int send_metakey(connection_t * c)
 	/* Further outgoing requests are encrypted with the key we just generated */
 
 	if(c->outcipher) {
-		EVP_EncryptInit(c->outctx, c->outcipher,
-						c->outkey + len - c->outcipher->key_len,
-						c->outkey + len - c->outcipher->key_len -
-						c->outcipher->iv_len);
+		if(!EVP_EncryptInit(c->outctx, c->outcipher,
+					(unsigned char *)c->outkey + len - c->outcipher->key_len,
+					(unsigned char *)c->outkey + len - c->outcipher->key_len -
+					c->outcipher->iv_len)) {
+			logger(LOG_ERR, "Error during initialisation of cipher for %s (%s): %s",
+					c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
+			return false;
+		}
 
-		c->status.encryptout = 1;
+		c->status.encryptout = true;
 	}
 
 	return x;
 }
 
-int metakey_h(connection_t * c)
-{
+bool metakey_h(connection_t *c) {
 	char buffer[MAX_STRING_SIZE];
 	int cipher, digest, maclength, compression;
 	int len;
 
-	cp();
-
-	if(sscanf
-	   (c->buffer, "%*d %d %d %d %d " MAX_STRING, &cipher, &digest, &maclength,
-		&compression, buffer) != 5) {
-		syslog(LOG_ERR, _("Got bad %s from %s (%s)"), "METAKEY", c->name,
+	if(sscanf(c->buffer, "%*d %d %d %d %d " MAX_STRING, &cipher, &digest, &maclength, &compression, buffer) != 5) {
+		logger(LOG_ERR, "Got bad %s from %s (%s)", "METAKEY", c->name,
 			   c->hostname);
-		return -1;
+		return false;
 	}
 
 	len = RSA_size(myself->connection->rsa_key);
@@ -237,36 +295,36 @@ int metakey_h(connection_t * c)
 	/* Check if the length of the meta key is all right */
 
 	if(strlen(buffer) != len * 2) {
-		syslog(LOG_ERR, _("Possible intruder %s (%s): %s"), c->name,
-			   c->hostname, "wrong keylength");
-		return -1;
+		logger(LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, "wrong keylength");
+		return false;
 	}
 
 	/* Allocate buffers for the meta key */
 
-	if(!c->inkey)
-		c->inkey = xmalloc(len);
+	c->inkey = xrealloc(c->inkey, len);
 
 	if(!c->inctx)
-		c->inctx = xmalloc(sizeof(*c->inctx));
+		c->inctx = xmalloc_and_zero(sizeof(*c->inctx));
 
 	/* Convert the challenge from hexadecimal back to binary */
 
-	hex2bin(buffer, buffer, len);
+	if(!hex2bin(buffer, buffer, len)) {
+		logger(LOG_ERR, "Got bad %s from %s(%s): %s", "METAKEY", c->name, c->hostname, "invalid key");
+		return false;
+	}
 
 	/* Decrypt the meta key */
 
-	if(RSA_private_decrypt(len, buffer, c->inkey, myself->connection->rsa_key, RSA_NO_PADDING) != len) {	/* See challenge() */
-		syslog(LOG_ERR, _("Error during encryption of meta key for %s (%s)"),
-			   c->name, c->hostname);
-		return -1;
+	if(RSA_private_decrypt(len, (unsigned char *)buffer, (unsigned char *)c->inkey, myself->connection->rsa_key, RSA_NO_PADDING) != len) {	/* See challenge() */
+		logger(LOG_ERR, "Error during decryption of meta key for %s (%s): %s",
+			   c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
+		return false;
 	}
 
-	if(debug_lvl >= DEBUG_SCARY_THINGS) {
+	ifdebug(SCARY_THINGS) {
 		bin2hex(c->inkey, buffer, len);
 		buffer[len * 2] = '\0';
-		syslog(LOG_DEBUG, _("Received random meta key (unencrypted): %s"),
-			   buffer);
+		logger(LOG_DEBUG, "Received random meta key (unencrypted): %s", buffer);
 	}
 
 	/* All incoming requests will now be encrypted. */
@@ -275,19 +333,22 @@ int metakey_h(connection_t * c)
 
 	if(cipher) {
 		c->incipher = EVP_get_cipherbynid(cipher);
-
+		
 		if(!c->incipher) {
-			syslog(LOG_ERR, _("%s (%s) uses unknown cipher!"), c->name,
-				   c->hostname);
-			return -1;
+			logger(LOG_ERR, "%s (%s) uses unknown cipher!", c->name, c->hostname);
+			return false;
 		}
 
-		EVP_DecryptInit(c->inctx, c->incipher,
-						c->inkey + len - c->incipher->key_len,
-						c->inkey + len - c->incipher->key_len -
-						c->incipher->iv_len);
+		if(!EVP_DecryptInit(c->inctx, c->incipher,
+					(unsigned char *)c->inkey + len - c->incipher->key_len,
+					(unsigned char *)c->inkey + len - c->incipher->key_len -
+					c->incipher->iv_len)) {
+			logger(LOG_ERR, "Error during initialisation of cipher from %s (%s): %s",
+					c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
+			return false;
+		}
 
-		c->status.decryptin = 1;
+		c->status.decryptin = true;
 	} else {
 		c->incipher = NULL;
 	}
@@ -298,15 +359,13 @@ int metakey_h(connection_t * c)
 		c->indigest = EVP_get_digestbynid(digest);
 
 		if(!c->indigest) {
-			syslog(LOG_ERR, _("Node %s (%s) uses unknown digest!"), c->name,
-				   c->hostname);
-			return -1;
+			logger(LOG_ERR, "Node %s (%s) uses unknown digest!", c->name, c->hostname);
+			return false;
 		}
 
 		if(c->inmaclength > c->indigest->md_size || c->inmaclength < 0) {
-			syslog(LOG_ERR, _("%s (%s) uses bogus MAC length!"), c->name,
-				   c->hostname);
-			return -1;
+			logger(LOG_ERR, "%s (%s) uses bogus MAC length!", c->name, c->hostname);
+			return false;
 		}
 	} else {
 		c->indigest = NULL;
@@ -319,25 +378,20 @@ int metakey_h(connection_t * c)
 	return send_challenge(c);
 }
 
-int send_challenge(connection_t * c)
-{
-	char buffer[MAX_STRING_SIZE];
-	int len, x;
-
-	cp();
-
+bool send_challenge(connection_t *c) {
 	/* CHECKME: what is most reasonable value for len? */
 
-	len = RSA_size(c->rsa_key);
+	int len = RSA_size(c->rsa_key);
 
 	/* Allocate buffers for the challenge */
 
-	if(!c->hischallenge)
-		c->hischallenge = xmalloc(len);
+	char buffer[2 * len + 1];
+
+	c->hischallenge = xrealloc(c->hischallenge, len);
 
 	/* Copy random data to the buffer */
 
-	RAND_bytes(c->hischallenge, len);
+	RAND_bytes((unsigned char *)c->hischallenge, len);
 
 	/* Convert to hex */
 
@@ -346,22 +400,17 @@ int send_challenge(connection_t * c)
 
 	/* Send the challenge */
 
-	x = send_request(c, "%d %s", CHALLENGE, buffer);
-
-	return x;
+	return send_request(c, "%d %s", CHALLENGE, buffer);
 }
 
-int challenge_h(connection_t * c)
-{
+bool challenge_h(connection_t *c) {
 	char buffer[MAX_STRING_SIZE];
 	int len;
 
-	cp();
-
 	if(sscanf(c->buffer, "%*d " MAX_STRING, buffer) != 1) {
-		syslog(LOG_ERR, _("Got bad %s from %s (%s)"), "CHALLENGE", c->name,
+		logger(LOG_ERR, "Got bad %s from %s (%s)", "CHALLENGE", c->name,
 			   c->hostname);
-		return -1;
+		return false;
 	}
 
 	len = RSA_size(myself->connection->rsa_key);
@@ -369,19 +418,21 @@ int challenge_h(connection_t * c)
 	/* Check if the length of the challenge is all right */
 
 	if(strlen(buffer) != len * 2) {
-		syslog(LOG_ERR, _("Possible intruder %s (%s): %s"), c->name,
+		logger(LOG_ERR, "Possible intruder %s (%s): %s", c->name,
 			   c->hostname, "wrong challenge length");
-		return -1;
+		return false;
 	}
 
 	/* Allocate buffers for the challenge */
 
-	if(!c->mychallenge)
-		c->mychallenge = xmalloc(len);
+	c->mychallenge = xrealloc(c->mychallenge, len);
 
 	/* Convert the challenge from hexadecimal back to binary */
 
-	hex2bin(buffer, c->mychallenge, len);
+	if(!hex2bin(buffer, c->mychallenge, len)) {
+		logger(LOG_ERR, "Got bad %s from %s(%s): %s", "CHALLENGE", c->name, c->hostname, "invalid challenge");
+		return false;
+	}
 
 	c->allow_request = CHAL_REPLY;
 
@@ -390,19 +441,19 @@ int challenge_h(connection_t * c)
 	return send_chal_reply(c);
 }
 
-int send_chal_reply(connection_t * c)
-{
+bool send_chal_reply(connection_t *c) {
 	char hash[EVP_MAX_MD_SIZE * 2 + 1];
 	EVP_MD_CTX ctx;
 
-	cp();
-
 	/* Calculate the hash from the challenge we received */
 
-	EVP_DigestInit(&ctx, c->indigest);
-	EVP_DigestUpdate(&ctx, c->mychallenge,
-					 RSA_size(myself->connection->rsa_key));
-	EVP_DigestFinal(&ctx, hash, NULL);
+	if(!EVP_DigestInit(&ctx, c->indigest)
+			|| !EVP_DigestUpdate(&ctx, c->mychallenge, RSA_size(myself->connection->rsa_key))
+			|| !EVP_DigestFinal(&ctx, (unsigned char *)hash, NULL)) {
+		logger(LOG_ERR, "Error during calculation of response for %s (%s): %s",
+			c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
+		return false;
+	}
 
 	/* Convert the hash to a hexadecimal formatted string */
 
@@ -414,51 +465,55 @@ int send_chal_reply(connection_t * c)
 	return send_request(c, "%d %s", CHAL_REPLY, hash);
 }
 
-int chal_reply_h(connection_t * c)
-{
+bool chal_reply_h(connection_t *c) {
 	char hishash[MAX_STRING_SIZE];
 	char myhash[EVP_MAX_MD_SIZE];
 	EVP_MD_CTX ctx;
 
-	cp();
-
 	if(sscanf(c->buffer, "%*d " MAX_STRING, hishash) != 1) {
-		syslog(LOG_ERR, _("Got bad %s from %s (%s)"), "CHAL_REPLY", c->name,
+		logger(LOG_ERR, "Got bad %s from %s (%s)", "CHAL_REPLY", c->name,
 			   c->hostname);
-		return -1;
+		return false;
 	}
 
 	/* Check if the length of the hash is all right */
 
 	if(strlen(hishash) != c->outdigest->md_size * 2) {
-		syslog(LOG_ERR, _("Possible intruder %s (%s): %s"), c->name,
-			   c->hostname, _("wrong challenge reply length"));
-		return -1;
+		logger(LOG_ERR, "Possible intruder %s (%s): %s", c->name,
+			   c->hostname, "wrong challenge reply length");
+		return false;
 	}
 
 	/* Convert the hash to binary format */
 
-	hex2bin(hishash, hishash, c->outdigest->md_size);
+	if(!hex2bin(hishash, hishash, c->outdigest->md_size)) {
+		logger(LOG_ERR, "Got bad %s from %s(%s): %s", "CHAL_REPLY", c->name, c->hostname, "invalid hash");
+		return false;
+	}
 
 	/* Calculate the hash from the challenge we sent */
 
-	EVP_DigestInit(&ctx, c->outdigest);
-	EVP_DigestUpdate(&ctx, c->hischallenge, RSA_size(c->rsa_key));
-	EVP_DigestFinal(&ctx, myhash, NULL);
+	if(!EVP_DigestInit(&ctx, c->outdigest)
+			|| !EVP_DigestUpdate(&ctx, c->hischallenge, RSA_size(c->rsa_key))
+			|| !EVP_DigestFinal(&ctx, (unsigned char *)myhash, NULL)) {
+		logger(LOG_ERR, "Error during calculation of response from %s (%s): %s",
+			c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
+		return false;
+	}
 
 	/* Verify the incoming hash with the calculated hash */
 
 	if(memcmp(hishash, myhash, c->outdigest->md_size)) {
-		syslog(LOG_ERR, _("Possible intruder %s (%s): %s"), c->name,
-			   c->hostname, _("wrong challenge reply"));
+		logger(LOG_ERR, "Possible intruder %s (%s): %s", c->name,
+			   c->hostname, "wrong challenge reply");
 
-		if(debug_lvl >= DEBUG_SCARY_THINGS) {
+		ifdebug(SCARY_THINGS) {
 			bin2hex(myhash, hishash, SHA_DIGEST_LENGTH);
 			hishash[SHA_DIGEST_LENGTH * 2] = '\0';
-			syslog(LOG_DEBUG, _("Expected challenge reply: %s"), hishash);
+			logger(LOG_DEBUG, "Expected challenge reply: %s", hishash);
 		}
 
-		return -1;
+		return false;
 	}
 
 	/* Identity has now been positively verified.
@@ -470,30 +525,40 @@ int chal_reply_h(connection_t * c)
 	return send_ack(c);
 }
 
-int send_ack(connection_t * c)
-{
+bool send_ack(connection_t *c) {
 	/* ACK message contains rest of the information the other end needs
 	   to create node_t and edge_t structures. */
 
-	int x;
 	struct timeval now;
-
-	cp();
+	bool choice;
 
 	/* Estimate weight */
 
 	gettimeofday(&now, NULL);
-	c->estimated_weight =
-		(now.tv_sec - c->start.tv_sec) * 1000 + (now.tv_usec -
-												 c->start.tv_usec) / 1000;
-	x = send_request(c, "%d %s %d %lx", ACK, myport, c->estimated_weight,
-					 c->options);
+	c->estimated_weight = (now.tv_sec - c->start.tv_sec) * 1000 + (now.tv_usec - c->start.tv_usec) / 1000;
 
-	return x;
+	/* Check some options */
+
+	if((get_config_bool(lookup_config(c->config_tree, "IndirectData"), &choice) && choice) || myself->options & OPTION_INDIRECT)
+		c->options |= OPTION_INDIRECT;
+
+	if((get_config_bool(lookup_config(c->config_tree, "TCPOnly"), &choice) && choice) || myself->options & OPTION_TCPONLY)
+		c->options |= OPTION_TCPONLY | OPTION_INDIRECT;
+
+	if(myself->options & OPTION_PMTU_DISCOVERY)
+		c->options |= OPTION_PMTU_DISCOVERY;
+
+	choice = myself->options & OPTION_CLAMP_MSS;
+	get_config_bool(lookup_config(c->config_tree, "ClampMSS"), &choice);
+	if(choice)
+		c->options |= OPTION_CLAMP_MSS;
+
+	get_config_int(lookup_config(c->config_tree, "Weight"), &c->estimated_weight);
+
+	return send_request(c, "%d %s %d %x", ACK, myport, c->estimated_weight, c->options);
 }
 
-void send_everything(connection_t * c)
-{
+static void send_everything(connection_t *c) {
 	avl_node_t *node, *node2;
 	node_t *n;
 	subnet_t *s;
@@ -501,36 +566,42 @@ void send_everything(connection_t * c)
 
 	/* Send all known subnets and edges */
 
+	if(tunnelserver) {
+		for(node = myself->subnet_tree->head; node; node = node->next) {
+			s = node->data;
+			send_add_subnet(c, s);
+		}
+
+		return;
+	}
+
 	for(node = node_tree->head; node; node = node->next) {
-		n = (node_t *) node->data;
+		n = node->data;
 
 		for(node2 = n->subnet_tree->head; node2; node2 = node2->next) {
-			s = (subnet_t *) node2->data;
+			s = node2->data;
 			send_add_subnet(c, s);
 		}
 
 		for(node2 = n->edge_tree->head; node2; node2 = node2->next) {
-			e = (edge_t *) node2->data;
+			e = node2->data;
 			send_add_edge(c, e);
 		}
 	}
 }
 
-int ack_h(connection_t * c)
-{
+bool ack_h(connection_t *c) {
 	char hisport[MAX_STRING_SIZE];
-	char *hisaddress, *dummy;
-	int weight;
-	long int options;
+	char *hisaddress;
+	int weight, mtu;
+	uint32_t options;
 	node_t *n;
+	bool choice;
 
-	cp();
-
-	if(sscanf
-	   (c->buffer, "%*d " MAX_STRING " %d %lx", hisport, &weight, &options) != 3) {
-		syslog(LOG_ERR, _("Got bad %s from %s (%s)"), "ACK", c->name,
+	if(sscanf(c->buffer, "%*d " MAX_STRING " %d %x", hisport, &weight, &options) != 3) {
+		logger(LOG_ERR, "Got bad %s from %s (%s)", "ACK", c->name,
 			   c->hostname);
-		return -1;
+		return false;
 	}
 
 	/* Check if we already have a node_t for him */
@@ -544,24 +615,41 @@ int ack_h(connection_t * c)
 	} else {
 		if(n->connection) {
 			/* Oh dear, we already have a connection to this node. */
-			if(debug_lvl >= DEBUG_CONNECTIONS)
-				syslog(LOG_DEBUG, _("Established a second connection with %s (%s), closing old connection"),
+			ifdebug(CONNECTIONS) logger(LOG_DEBUG, "Established a second connection with %s (%s), closing old connection",
 					   n->name, n->hostname);
-			terminate_connection(n->connection, 0);
+			terminate_connection(n->connection, false);
+			/* Run graph algorithm to purge key and make sure up/down scripts are rerun with new IP addresses and stuff */
+			graph();
 		}
 	}
 
 	n->connection = c;
 	c->node = n;
+	if(!(c->options & options & OPTION_PMTU_DISCOVERY)) {
+		c->options &= ~OPTION_PMTU_DISCOVERY;
+		options &= ~OPTION_PMTU_DISCOVERY;
+	}
 	c->options |= options;
 
+	if(get_config_int(lookup_config(c->config_tree, "PMTU"), &mtu) && mtu < n->mtu)
+		n->mtu = mtu;
+
+	if(get_config_int(lookup_config(config_tree, "PMTU"), &mtu) && mtu < n->mtu)
+		n->mtu = mtu;
+
+	if(get_config_bool(lookup_config(c->config_tree, "ClampMSS"), &choice)) {
+		if(choice)
+			c->options |= OPTION_CLAMP_MSS;
+		else
+			c->options &= ~OPTION_CLAMP_MSS;
+	}
+
 	/* Activate this connection */
 
 	c->allow_request = ALL;
-	c->status.active = 1;
+	c->status.active = true;
 
-	if(debug_lvl >= DEBUG_CONNECTIONS)
-		syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), c->name,
+	ifdebug(CONNECTIONS) logger(LOG_NOTICE, "Connection with %s (%s) activated", c->name,
 			   c->hostname);
 
 	/* Send him everything we know */
@@ -571,13 +659,11 @@ int ack_h(connection_t * c)
 	/* Create an edge_t for this connection */
 
 	c->edge = new_edge();
-	cp();
 	c->edge->from = myself;
 	c->edge->to = n;
-	sockaddr2str(&c->address, &hisaddress, &dummy);
+	sockaddr2str(&c->address, &hisaddress, NULL);
 	c->edge->address = str2sockaddr(hisaddress, hisport);
 	free(hisaddress);
-	free(dummy);
 	c->edge->weight = (weight + c->estimated_weight) / 2;
 	c->edge->connection = c;
 	c->edge->options = c->options;
@@ -586,11 +672,14 @@ int ack_h(connection_t * c)
 
 	/* Notify everyone of the new edge */
 
-	send_add_edge(broadcast, c->edge);
+	if(tunnelserver)
+		send_add_edge(c, c->edge);
+	else
+		send_add_edge(everyone, c->edge);
 
 	/* Run MST and SSSP algorithms */
 
 	graph();
 
-	return 0;
+	return true;
 }