]> git.meshlink.io Git - meshlink/blobdiff - src/net_setup.c
Use ECDSA to sign ECDH key exchange for UDP session keys.
[meshlink] / src / net_setup.c
index 597c3cb754575ab16f5b69d82164eb0377bc210b..91f7609bfa8d64a7015ae79a725ce6b3ca290473 100644 (file)
@@ -3,6 +3,7 @@
     Copyright (C) 1998-2005 Ivo Timmermans,
                   2000-2010 Guus Sliepen <guus@tinc-vpn.org>
                   2006      Scott Lamb <slamb@slamb.org>
+                  2010      Brandon Black <blblack@gmail.com>
 
     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
@@ -28,6 +29,7 @@
 #include "control.h"
 #include "device.h"
 #include "digest.h"
+#include "ecdsa.h"
 #include "graph.h"
 #include "logger.h"
 #include "net.h"
 char *myport;
 static struct event device_ev;
 
+bool node_read_ecdsa_public_key(node_t *n) {
+       if(ecdsa_active(&n->ecdsa))
+               return true;
+
+       splay_tree_t *config_tree;
+       FILE *fp;
+       char *fname;
+       char *p;
+       bool result = false;
+
+       xasprintf(&fname, "%s/hosts/%s", confbase, n->name);
+
+       init_configuration(&config_tree);
+       if(!read_config_file(config_tree, fname))
+               goto exit;
+
+       /* First, check for simple ECDSAPublicKey statement */
+
+       if(get_config_string(lookup_config(config_tree, "ECDSAPublicKey"), &p)) {
+               result = ecdsa_set_base64_public_key(&n->ecdsa, p);
+               free(p);
+               goto exit;
+       }
+
+       /* Else, check for ECDSAPublicKeyFile statement and read it */
+
+       free(fname);
+
+       if(!get_config_string(lookup_config(config_tree, "ECDSAPublicKeyFile"), &fname))
+               xasprintf(&fname, "%s/hosts/%s", confbase, n->name);
+
+       fp = fopen(fname, "r");
+
+       if(!fp) {
+               logger(LOG_ERR, "Error reading ECDSA public key file `%s': %s", fname, strerror(errno));
+               goto exit;
+       }
+
+       result = ecdsa_read_pem_public_key(&n->ecdsa, fp);
+       fclose(fp);
+
+exit:
+       exit_configuration(&config_tree);
+       free(fname);
+       return result;
+}
+
+bool read_ecdsa_public_key(connection_t *c) {
+       FILE *fp;
+       char *fname;
+       char *p;
+       bool result;
+
+       /* First, check for simple ECDSAPublicKey statement */
+
+       if(get_config_string(lookup_config(c->config_tree, "ECDSAPublicKey"), &p)) {
+               result = ecdsa_set_base64_public_key(&c->ecdsa, p);
+               free(p);
+               return result;
+       }
+
+       /* Else, check for ECDSAPublicKeyFile statement and read it */
+
+       if(!get_config_string(lookup_config(c->config_tree, "ECDSAPublicKeyFile"), &fname))
+               xasprintf(&fname, "%s/hosts/%s", confbase, c->name);
+
+       fp = fopen(fname, "r");
+
+       if(!fp) {
+               logger(LOG_ERR, "Error reading ECDSA public key file `%s': %s",
+                          fname, strerror(errno));
+               free(fname);
+               return false;
+       }
+
+       result = ecdsa_read_pem_public_key(&c->ecdsa, fp);
+       fclose(fp);
+
+       if(!result) 
+               logger(LOG_ERR, "Reading ECDSA public key file `%s' failed: %s", fname, strerror(errno));
+       free(fname);
+       return result;
+}
+
 bool read_rsa_public_key(connection_t *c) {
        FILE *fp;
        char *fname;
@@ -80,7 +166,48 @@ bool read_rsa_public_key(connection_t *c) {
        return result;
 }
 
-bool read_rsa_private_key() {
+static bool read_ecdsa_private_key(void) {
+       FILE *fp;
+       char *fname;
+       bool result;
+
+       /* Check for PrivateKeyFile statement and read it */
+
+       if(!get_config_string(lookup_config(config_tree, "ECDSAPrivateKeyFile"), &fname))
+               xasprintf(&fname, "%s/ecdsa_key.priv", confbase);
+
+       fp = fopen(fname, "r");
+
+       if(!fp) {
+               logger(LOG_ERR, "Error reading ECDSA private key file `%s': %s",
+                          fname, strerror(errno));
+               free(fname);
+               return false;
+       }
+
+#if !defined(HAVE_MINGW) && !defined(HAVE_CYGWIN)
+       struct stat s;
+
+       if(fstat(fileno(fp), &s)) {
+               logger(LOG_ERR, "Could not stat ECDSA private key file `%s': %s'", fname, strerror(errno));
+               free(fname);
+               return false;
+       }
+
+       if(s.st_mode & ~0100700)
+               logger(LOG_WARNING, "Warning: insecure file permissions for ECDSA private key file `%s'!", fname);
+#endif
+
+       result = ecdsa_read_pem_private_key(&myself->connection->ecdsa, fp);
+       fclose(fp);
+
+       if(!result) 
+               logger(LOG_ERR, "Reading ECDSA private key file `%s' failed: %s", fname, strerror(errno));
+       free(fname);
+       return result;
+}
+
+static bool read_rsa_private_key(void) {
        FILE *fp;
        char *fname;
        char *n, *d;
@@ -89,7 +216,7 @@ bool read_rsa_private_key() {
        /* First, check for simple PrivateKey statement */
 
        if(get_config_string(lookup_config(config_tree, "PrivateKey"), &d)) {
-               if(!get_config_string(lookup_config(myself->connection->config_tree, "PublicKey"), &n)) {
+               if(!get_config_string(lookup_config(config_tree, "PublicKey"), &n)) {
                        logger(LOG_ERR, "PrivateKey used but no PublicKey found!");
                        free(d);
                        return false;
@@ -142,11 +269,11 @@ static void keyexpire_handler(int fd, short events, void *data) {
        regenerate_key();
 }
 
-void regenerate_key() {
+void regenerate_key(void) {
        if(timeout_initialized(&keyexpire_event)) {
                ifdebug(STATUS) logger(LOG_INFO, "Expiring symmetric keys");
                event_del(&keyexpire_event);
-               send_key_changed(broadcast, myself);
+               send_key_changed();
        } else {
                timeout_set(&keyexpire_event, keyexpire_handler, NULL);
        }
@@ -157,14 +284,14 @@ void regenerate_key() {
 /*
   Read Subnets from all host config files
 */
-static void load_all_subnets(void) {
+void load_all_subnets(void) {
        DIR *dir;
        struct dirent *ent;
        char *dname;
        char *fname;
        splay_tree_t *config_tree;
        config_t *cfg;
-       subnet_t *s;
+       subnet_t *s, *s2;
        node_t *n;
        bool result;
 
@@ -181,9 +308,6 @@ static void load_all_subnets(void) {
                        continue;
 
                n = lookup_node(ent->d_name);
-               if(n)
-                       continue;
-
                #ifdef _DIRENT_HAVE_D_TYPE
                //if(ent->d_type != DT_REG)
                //      continue;
@@ -196,15 +320,21 @@ static void load_all_subnets(void) {
                if(!result)
                        continue;
 
-               n = new_node();
-               n->name = xstrdup(ent->d_name);
-               node_add(n);
+               if(!n) {
+                       n = new_node();
+                       n->name = xstrdup(ent->d_name);
+                       node_add(n);
+               }
 
                for(cfg = lookup_config(config_tree, "Subnet"); cfg; cfg = lookup_config_next(config_tree, cfg)) {
                        if(!get_config_subnet(cfg, &s))
                                continue;
 
-                       subnet_add(n, s);
+                       if((s2 = lookup_subnet(n, s))) {
+                               s2->expires = -1;
+                       } else {
+                               subnet_add(n, s);
+                       }
                }
 
                exit_configuration(&config_tree);
@@ -216,25 +346,27 @@ static void load_all_subnets(void) {
 /*
   Configure node_t myself and set up the local sockets (listen only)
 */
-bool setup_myself(void) {
+static bool setup_myself(void) {
        config_t *cfg;
        subnet_t *subnet;
        char *name, *hostname, *mode, *afname, *cipher, *digest;
+       char *fname = NULL;
        char *address = NULL;
        char *envp[5];
        struct addrinfo *ai, *aip, hint = {0};
        bool choice;
        int i, err;
+       int replaywin_int;
 
        myself = new_node();
        myself->connection = new_connection();
-       init_configuration(&myself->connection->config_tree);
 
        myself->hostname = xstrdup("MYSELF");
        myself->connection->hostname = xstrdup("MYSELF");
 
        myself->connection->options = 0;
-       myself->connection->protocol_version = PROT_CURRENT;
+       myself->connection->protocol_major = PROT_MAJOR;
+       myself->connection->protocol_minor = PROT_MINOR;
 
        if(!get_config_string(lookup_config(config_tree, "Name"), &name)) {     /* Not acceptable */
                logger(LOG_ERR, "Name for tinc daemon required!");
@@ -249,22 +381,35 @@ bool setup_myself(void) {
 
        myself->name = name;
        myself->connection->name = xstrdup(name);
+       xasprintf(&fname, "%s/hosts/%s", confbase, name);
+       read_config_options(config_tree, name);
+       read_config_file(config_tree, fname);
+       free(fname);
 
-       if(!read_connection_config(myself->connection)) {
-               logger(LOG_ERR, "Cannot open host configuration file for myself!");
+       get_config_bool(lookup_config(config_tree, "ExperimentalProtocol"), &experimental);
+
+       if(experimental && !read_ecdsa_private_key())
                return false;
-       }
 
        if(!read_rsa_private_key())
                return false;
 
-       if(!get_config_string(lookup_config(config_tree, "Port"), &myport)
-                       && !get_config_string(lookup_config(myself->connection->config_tree, "Port"), &myport))
+       if(!get_config_string(lookup_config(config_tree, "Port"), &myport))
                myport = xstrdup("655");
 
+       if(!atoi(myport)) {
+               struct addrinfo *ai = str2addrinfo("localhost", myport, SOCK_DGRAM);
+               sockaddr_t sa;
+               if(!ai || !ai->ai_addr)
+                       return false;
+               free(myport);
+               memcpy(&sa, ai->ai_addr, ai->ai_addrlen);
+               sockaddr2str(&sa, NULL, &myport);
+       }
+
        /* Read in all the subnets specified in the host configuration file */
 
-       cfg = lookup_config(myself->connection->config_tree, "Subnet");
+       cfg = lookup_config(config_tree, "Subnet");
 
        while(cfg) {
                if(!get_config_subnet(cfg, &subnet))
@@ -272,7 +417,7 @@ bool setup_myself(void) {
 
                subnet_add(myself, subnet);
 
-               cfg = lookup_config_next(myself->connection->config_tree, cfg);
+               cfg = lookup_config_next(config_tree, cfg);
        }
 
        /* Check some options */
@@ -283,12 +428,6 @@ bool setup_myself(void) {
        if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice) && choice)
                myself->options |= OPTION_TCPONLY;
 
-       if(get_config_bool(lookup_config(myself->connection->config_tree, "IndirectData"), &choice) && choice)
-               myself->options |= OPTION_INDIRECT;
-
-       if(get_config_bool(lookup_config(myself->connection->config_tree, "TCPOnly"), &choice) && choice)
-               myself->options |= OPTION_TCPONLY;
-
        if(myself->options & OPTION_TCPONLY)
                myself->options |= OPTION_INDIRECT;
 
@@ -326,14 +465,12 @@ bool setup_myself(void) {
        }
 
        choice = true;
-       get_config_bool(lookup_config(myself->connection->config_tree, "PMTUDiscovery"), &choice);
        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);
-       get_config_bool(lookup_config(myself->connection->config_tree, "ClampMSS"), &choice);
        if(choice)
                myself->options |= OPTION_CLAMP_MSS;
 
@@ -355,6 +492,28 @@ bool setup_myself(void) {
        } else
                maxtimeout = 900;
 
+       if(get_config_int(lookup_config(config_tree, "UDPRcvBuf"), &udp_rcvbuf)) {
+               if(udp_rcvbuf <= 0) {
+                       logger(LOG_ERR, "UDPRcvBuf cannot be negative!");
+                       return false;
+               }
+       }
+
+       if(get_config_int(lookup_config(config_tree, "UDPSndBuf"), &udp_sndbuf)) {
+               if(udp_sndbuf <= 0) {
+                       logger(LOG_ERR, "UDPSndBuf cannot be negative!");
+                       return false;
+               }
+       }
+
+       if(get_config_int(lookup_config(config_tree, "ReplayWindow"), &replaywin_int)) {
+               if(replaywin_int < 0) {
+                       logger(LOG_ERR, "ReplayWindow cannot be negative!");
+                       return false;
+               }
+               replaywin = (unsigned)replaywin_int;
+       }
+
        if(get_config_string(lookup_config(config_tree, "AddressFamily"), &afname)) {
                if(!strcasecmp(afname, "IPv4"))
                        addressfamily = AF_INET;
@@ -373,7 +532,7 @@ bool setup_myself(void) {
 
        /* Generate packet encryption key */
 
-       if(!get_config_string(lookup_config(myself->connection->config_tree, "Cipher"), &cipher))
+       if(!get_config_string(lookup_config(config_tree, "Cipher"), &cipher))
                cipher = xstrdup("blowfish");
 
        if(!cipher_open_by_name(&myself->incipher, cipher)) {
@@ -388,11 +547,11 @@ bool setup_myself(void) {
 
        /* Check if we want to use message authentication codes... */
 
-       if(!get_config_string(lookup_config(myself->connection->config_tree, "Digest"), &digest))
+       if(!get_config_string(lookup_config(config_tree, "Digest"), &digest))
                digest = xstrdup("sha1");
 
        int maclength = 4;
-       get_config_int(lookup_config(myself->connection->config_tree, "MACLength"), &maclength);
+       get_config_int(lookup_config(config_tree, "MACLength"), &maclength);
 
        if(maclength < 0) {
                logger(LOG_ERR, "Bogus MAC length!");
@@ -406,7 +565,7 @@ bool setup_myself(void) {
 
        /* Compression */
 
-       if(get_config_int(lookup_config(myself->connection->config_tree, "Compression"), &myself->incompression)) {
+       if(get_config_int(lookup_config(config_tree, "Compression"), &myself->incompression)) {
                if(myself->incompression < 0 || myself->incompression > 11) {
                        logger(LOG_ERR, "Bogus compression level!");
                        return false;
@@ -452,7 +611,7 @@ bool setup_myself(void) {
 
        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 */
@@ -498,7 +657,7 @@ bool setup_myself(void) {
                                  EV_READ|EV_PERSIST,
                                  handle_new_meta_connection, NULL);
                if(event_add(&listen_socket[listen_sockets].ev_tcp, NULL) < 0) {
-                       logger(LOG_EMERG, "event_add failed: %s", strerror(errno));
+                       logger(LOG_ERR, "event_add failed: %s", strerror(errno));
                        abort();
                }
 
@@ -507,7 +666,7 @@ bool setup_myself(void) {
                                  EV_READ|EV_PERSIST,
                                  handle_incoming_vpn_data, NULL);
                if(event_add(&listen_socket[listen_sockets].ev_udp, NULL) < 0) {
-                       logger(LOG_EMERG, "event_add failed: %s", strerror(errno));
+                       logger(LOG_ERR, "event_add failed: %s", strerror(errno));
                        abort();
                }
 
@@ -581,7 +740,7 @@ void close_network_connections(void) {
        for(node = connection_tree->head; node; node = next) {
                next = node->next;
                c = node->data;
-               c->outgoing = false;
+               c->outgoing = NULL;
                terminate_connection(c, false);
        }