tinc/src/net.c

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2000-03-26 00:33:07 +00:00
/*
net.c -- most of the network code
Copyright (C) 1998-2001 Ivo Timmermans <itimmermans@bigfoot.com>,
2000,2001 Guus Sliepen <guus@sliepen.warande.net>
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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
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
$Id: net.c,v 1.35.4.139 2001/10/27 15:19:13 guus Exp $
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*/
#include "config.h"
#include <errno.h>
#include <fcntl.h>
#include <netdb.h>
#include <netinet/in.h>
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#ifdef HAVE_LINUX
#include <netinet/ip.h>
#include <netinet/tcp.h>
#endif
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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/signal.h>
#include <sys/time.h>
#include <sys/types.h>
#include <syslog.h>
#include <unistd.h>
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#include <sys/ioctl.h>
/* SunOS really wants sys/socket.h BEFORE net/if.h,
and FreeBSD wants these lines below the rest. */
#include <arpa/inet.h>
#include <sys/socket.h>
#include <net/if.h>
#include <openssl/rand.h>
#include <openssl/evp.h>
#include <openssl/pem.h>
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#ifndef HAVE_RAND_PSEUDO_BYTES
#define RAND_pseudo_bytes RAND_bytes
#endif
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#include <utils.h>
#include <xalloc.h>
#include <avl_tree.h>
#include <list.h>
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#include "conf.h"
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#include "connection.h"
#include "meta.h"
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#include "net.h"
#include "netutl.h"
#include "process.h"
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#include "protocol.h"
#include "subnet.h"
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#include "process.h"
#include "route.h"
#include "device.h"
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#include "system.h"
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int maxtimeout = 900;
int seconds_till_retry = 5;
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int tcp_socket = -1;
int udp_socket = -1;
int keylifetime = 0;
int keyexpires = 0;
/* VPN packet I/O */
void receive_udppacket(node_t *n, vpn_packet_t *inpkt)
{
vpn_packet_t outpkt;
int outlen, outpad;
EVP_CIPHER_CTX ctx;
cp
/* Decrypt the packet */
EVP_DecryptInit(&ctx, myself->cipher, myself->key, myself->key + myself->cipher->key_len);
EVP_DecryptUpdate(&ctx, outpkt.salt, &outlen, inpkt->salt, inpkt->len);
EVP_DecryptFinal(&ctx, outpkt.salt + outlen, &outpad);
outlen += outpad;
outpkt.len = outlen - sizeof(outpkt.salt);
receive_packet(n, &outpkt);
cp
}
void receive_tcppacket(connection_t *c, char *buffer, int len)
{
vpn_packet_t outpkt;
cp
outpkt.len = len;
memcpy(outpkt.data, buffer, len);
receive_packet(c->node, &outpkt);
cp
}
void receive_packet(node_t *n, vpn_packet_t *packet)
{
cp
if(debug_lvl >= DEBUG_TRAFFIC)
syslog(LOG_DEBUG, _("Received packet of %d bytes from %s (%s)"), packet->len, n->name, n->hostname);
route_incoming(n, packet);
cp
}
void send_udppacket(node_t *n, vpn_packet_t *inpkt)
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{
vpn_packet_t outpkt;
int outlen, outpad;
EVP_CIPHER_CTX ctx;
struct sockaddr_in to;
socklen_t tolen = sizeof(to);
vpn_packet_t *copy;
cp
if(!n->status.validkey)
{
if(debug_lvl >= DEBUG_TRAFFIC)
syslog(LOG_INFO, _("No valid key known yet for %s (%s), queueing packet"),
n->name, n->hostname);
/* Since packet is on the stack of handle_tap_input(),
we have to make a copy of it first. */
copy = xmalloc(sizeof(vpn_packet_t));
memcpy(copy, inpkt, sizeof(vpn_packet_t));
list_insert_tail(n->queue, copy);
if(!n->status.waitingforkey)
send_req_key(n->nexthop->connection, myself, n);
return;
}
/* Encrypt the packet. */
RAND_pseudo_bytes(inpkt->salt, sizeof(inpkt->salt));
EVP_EncryptInit(&ctx, n->cipher, n->key, n->key + n->cipher->key_len);
EVP_EncryptUpdate(&ctx, outpkt.salt, &outlen, inpkt->salt, inpkt->len + sizeof(inpkt->salt));
EVP_EncryptFinal(&ctx, outpkt.salt + outlen, &outpad);
outlen += outpad;
to.sin_family = AF_INET;
to.sin_addr.s_addr = htonl(n->address);
to.sin_port = htons(n->port);
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if((sendto(udp_socket, (char *) outpkt.salt, outlen, 0, (const struct sockaddr *)&to, tolen)) < 0)
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{
syslog(LOG_ERR, _("Error sending packet to %s (%s): %m"),
n->name, n->hostname);
return;
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}
cp
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}
/*
send a packet to the given vpn ip.
*/
void send_packet(node_t *n, vpn_packet_t *packet)
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{
cp
if(debug_lvl >= DEBUG_TRAFFIC)
syslog(LOG_ERR, _("Sending packet of %d bytes to %s (%s)"),
packet->len, n->name, n->hostname);
if(n == myself)
{
if(debug_lvl >= DEBUG_TRAFFIC)
{
syslog(LOG_NOTICE, _("Packet is looping back to us!"));
}
return;
}
if(!n->status.active)
{
if(debug_lvl >= DEBUG_TRAFFIC)
syslog(LOG_INFO, _("%s (%s) is not active, dropping packet"),
n->name, n->hostname);
return;
}
/* FIXME
if(n->via == myself)
via = n->nexthop;
else
via = n->via;
if(via != n && debug_lvl >= DEBUG_TRAFFIC)
syslog(LOG_ERR, _("Sending packet to %s via %s (%s)"),
n->name, via->name, via->hostname);
if((myself->options | via->options) & OPTION_TCPONLY)
{
if(send_tcppacket(via->connection, packet))
terminate_connection(via->connection, 1);
}
else
send_udppacket(via, packet);
*/
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}
/* Broadcast a packet to all active direct connections */
void broadcast_packet(node_t *from, vpn_packet_t *packet)
{
avl_node_t *node;
connection_t *c;
cp
if(debug_lvl >= DEBUG_TRAFFIC)
syslog(LOG_INFO, _("Broadcasting packet of %d bytes from %s (%s)"),
packet->len, from->name, from->hostname);
for(node = connection_tree->head; node; node = node->next)
{
c = (connection_t *)node->data;
if(c->status.active && c != from->nexthop->connection)
send_packet(c->node, packet);
}
cp
}
void flush_queue(node_t *n)
{
list_node_t *node, *next;
cp
if(debug_lvl >= DEBUG_TRAFFIC)
syslog(LOG_INFO, _("Flushing queue for %s (%s)"), n->name, n->hostname);
for(node = n->queue->head; node; node = next)
{
next = node->next;
send_udppacket(n, (vpn_packet_t *)node->data);
list_delete_node(n->queue, node);
}
cp
}
/* Setup sockets */
int setup_listen_socket(int port)
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{
int nfd, flags;
struct sockaddr_in a;
int option;
char *interface;
char *address;
ip_mask_t *ipmask;
cp
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if((nfd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0)
{
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syslog(LOG_ERR, _("Creating metasocket failed: %m"));
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return -1;
}
flags = fcntl(nfd, F_GETFL);
if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0)
{
close(nfd);
syslog(LOG_ERR, _("System call `%s' failed: %m"),
"fcntl");
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return -1;
}
/* Optimize TCP settings */
option = 1;
setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &option, sizeof(option));
setsockopt(nfd, SOL_SOCKET, SO_KEEPALIVE, &option, sizeof(option));
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#ifdef HAVE_LINUX
setsockopt(nfd, SOL_TCP, TCP_NODELAY, &option, sizeof(option));
option = IPTOS_LOWDELAY;
setsockopt(nfd, SOL_IP, IP_TOS, &option, sizeof(option));
if(get_config_string(lookup_config(config_tree, "BindToInterface"), &interface))
if(setsockopt(nfd, SOL_SOCKET, SO_BINDTODEVICE, interface, strlen(interface)))
{
close(nfd);
syslog(LOG_ERR, _("Can't bind to interface %s: %m"), interface);
return -1;
}
#endif
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memset(&a, 0, sizeof(a));
a.sin_family = AF_INET;
a.sin_addr.s_addr = htonl(INADDR_ANY);
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a.sin_port = htons(port);
if(get_config_string(lookup_config(config_tree, "BindToAddress"), &address))
{
ipmask = strtoip(address);
if(ipmask)
{
a.sin_addr.s_addr = htonl(ipmask->address);
free(ipmask);
}
}
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if(bind(nfd, (struct sockaddr *)&a, sizeof(struct sockaddr)))
{
close(nfd);
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syslog(LOG_ERR, _("Can't bind to port %hd/tcp: %m"), port);
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return -1;
}
if(listen(nfd, 3))
{
close(nfd);
syslog(LOG_ERR, _("System call `%s' failed: %m"),
"listen");
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return -1;
}
cp
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return nfd;
}
int setup_vpn_in_socket(int port)
{
int nfd, flags;
struct sockaddr_in a;
const int one = 1;
cp
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if((nfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0)
{
close(nfd);
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syslog(LOG_ERR, _("Creating socket failed: %m"));
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return -1;
}
setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
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flags = fcntl(nfd, F_GETFL);
if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0)
{
close(nfd);
syslog(LOG_ERR, _("System call `%s' failed: %m"),
"fcntl");
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return -1;
}
memset(&a, 0, sizeof(a));
a.sin_family = AF_INET;
a.sin_port = htons(port);
a.sin_addr.s_addr = htonl(INADDR_ANY);
if(bind(nfd, (struct sockaddr *)&a, sizeof(struct sockaddr)))
{
close(nfd);
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syslog(LOG_ERR, _("Can't bind to port %hd/udp: %m"), port);
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return -1;
}
cp
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return nfd;
}
int setup_outgoing_socket(connection_t *c)
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{
int flags;
struct sockaddr_in a;
int option;
cp
if(debug_lvl >= DEBUG_CONNECTIONS)
syslog(LOG_INFO, _("Trying to connect to %s (%s)"), c->name, c->hostname);
c->socket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
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if(c->socket == -1)
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{
syslog(LOG_ERR, _("Creating socket for %s port %d failed: %m"),
c->hostname, c->port);
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return -1;
}
/* Bind first to get a fix on our source port???
a.sin_family = AF_INET;
a.sin_port = htons(0);
a.sin_addr.s_addr = htonl(INADDR_ANY);
if(bind(c->socket, (struct sockaddr *)&a, sizeof(struct sockaddr)))
{
close(c->socket);
syslog(LOG_ERR, _("System call `%s' failed: %m"), "bind");
return -1;
}
*/
/* Optimize TCP settings?
option = 1;
setsockopt(c->socket, SOL_SOCKET, SO_KEEPALIVE, &option, sizeof(option));
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#ifdef HAVE_LINUX
setsockopt(c->socket, SOL_TCP, TCP_NODELAY, &option, sizeof(option));
option = IPTOS_LOWDELAY;
setsockopt(c->socket, SOL_IP, IP_TOS, &option, sizeof(option));
#endif
*/
/* Connect */
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a.sin_family = AF_INET;
a.sin_port = htons(c->port);
a.sin_addr.s_addr = htonl(c->address);
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if(connect(c->socket, (struct sockaddr *)&a, sizeof(a)) == -1)
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{
close(c->socket);
syslog(LOG_ERR, _("%s port %hd: %m"), c->hostname, c->port);
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return -1;
}
flags = fcntl(c->socket, F_GETFL);
if(fcntl(c->socket, F_SETFL, flags | O_NONBLOCK) < 0)
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{
close(c->socket);
syslog(LOG_ERR, _("fcntl for %s port %d: %m"),
c->hostname, c->port);
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return -1;
}
if(debug_lvl >= DEBUG_CONNECTIONS)
syslog(LOG_INFO, _("Connected to %s port %hd"),
c->hostname, c->port);
cp
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return 0;
}
int setup_outgoing_connection(char *name)
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{
connection_t *c;
struct hostent *h;
cp
c = new_connection();
c->name = xstrdup(name);
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read_connection_config(c);
if(!get_config_string(lookup_config(c->config_tree, "Address"), &c->hostname))
{
syslog(LOG_ERR, _("No address specified for %s"), c->name);
free_connection(c);
return -1;
}
if(!get_config_port(lookup_config(c->config_tree, "Port"), &c->port))
{
syslog(LOG_ERR, _("No port specified for %s"), c->name);
free_connection(c);
return -1;
}
if(!(h = gethostbyname(c->hostname)))
{
syslog(LOG_ERR, _("Error looking up `%s': %m"), c->hostname);
free_connection(c);
return -1;
}
c->address = ntohl(*((ipv4_t*)(h->h_addr_list[0])));
c->hostname = hostlookup(htonl(c->address));
if(setup_outgoing_socket(c) < 0)
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{
syslog(LOG_ERR, _("Could not set up a meta connection to %s (%s)"),
c->name, c->hostname);
free_connection(c);
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return -1;
}
c->status.outgoing = 1;
c->last_ping_time = time(NULL);
connection_add(c);
send_id(c);
cp
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return 0;
}
int read_rsa_public_key(connection_t *c)
{
FILE *fp;
char *fname;
char *key;
void *result;
cp
if(!c->rsa_key)
c->rsa_key = RSA_new();
/* 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");
return 0;
}
/* Else, check for PublicKeyFile statement and read it */
if(get_config_string(lookup_config(c->config_tree, "PublicKeyFile"), &fname))
{
if(is_safe_path(fname))
{
if((fp = fopen(fname, "r")) == NULL)
{
syslog(LOG_ERR, _("Error reading RSA public key file `%s': %m"),
fname);
return -1;
}
result = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
fclose(fp);
if(!result)
{
syslog(LOG_ERR, _("Reading RSA public key file `%s' failed: %m"),
fname);
return -1;
}
return 0;
}
else
return -1;
}
/* Else, check if a harnessed public key is in the config file */
result = NULL;
asprintf(&fname, "%s/hosts/%s", confbase, c->name);
if((fp = fopen(fname, "r")))
{
result = PEM_read_RSAPublicKey(fp, &c->rsa_key, NULL, NULL);
fclose(fp);
free(fname);
}
free(fname);
if(result)
return 0;
else
{
syslog(LOG_ERR, _("No public key for %s specified!"), c->name);
return -1;
}
}
int read_rsa_private_key(void)
{
FILE *fp;
void *result;
char *fname, *key;
cp
if(!myself->connection->rsa_key)
myself->connection->rsa_key = RSA_new();
if(get_config_string(lookup_config(config_tree, "PrivateKey"), &key))
{
BN_hex2bn(&myself->connection->rsa_key->d, key);
BN_hex2bn(&myself->connection->rsa_key->e, "FFFF");
}
else if(get_config_string(lookup_config(config_tree, "PrivateKeyFile"), &fname))
{
if((fp = fopen(fname, "r")) == NULL)
{
syslog(LOG_ERR, _("Error reading RSA private key file `%s': %m"),
fname);
return -1;
}
result = PEM_read_RSAPrivateKey(fp, &myself->connection->rsa_key, NULL, NULL);
fclose(fp);
if(!result)
{
syslog(LOG_ERR, _("Reading RSA private key file `%s' failed: %m"),
fname);
return -1;
}
}
else
{
syslog(LOG_ERR, _("No private key for tinc daemon specified!"));
return -1;
}
cp
return 0;
}
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/*
Configure node_t myself and set up the local sockets (listen only)
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*/
int setup_myself(void)
{
config_t *cfg;
subnet_t *subnet;
char *name, *mode;
int choice;
cp
myself = new_node();
myself->connection = new_connection();
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asprintf(&myself->hostname, _("MYSELF"));
asprintf(&myself->connection->hostname, _("MYSELF"));
myself->connection->options = 0;
myself->connection->protocol_version = PROT_CURRENT;
if(!get_config_string(lookup_config(config_tree, "Name"), &name)) /* Not acceptable */
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{
syslog(LOG_ERR, _("Name for tinc daemon required!"));
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return -1;
}
if(check_id(name))
{
syslog(LOG_ERR, _("Invalid name for myself!"));
free(name);
return -1;
}
myself->name = name;
myself->connection->name = xstrdup(name);
cp
if(read_rsa_private_key())
return -1;
if(read_connection_config(myself->connection))
{
syslog(LOG_ERR, _("Cannot open host configuration file for myself!"));
return -1;
}
if(read_rsa_public_key(myself->connection))
return -1;
cp
/*
if(RSA_check_key(rsa_key) != 1)
{
syslog(LOG_ERR, _("Invalid public/private keypair!"));
return -1;
}
*/
if(!get_config_port(lookup_config(myself->connection->config_tree, "Port"), &myself->port))
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myself->port = 655;
myself->connection->port = myself->port;
/* Read in all the subnets specified in the host configuration file */
cfg = lookup_config(myself->connection->config_tree, "Subnet");
while(cfg)
{
if(!get_config_subnet(cfg, &subnet))
return -1;
subnet_add(myself, subnet);
cfg = lookup_config_next(myself->connection->config_tree, cfg);
}
cp
/* Check some options */
if(get_config_bool(lookup_config(config_tree, "IndirectData"), &choice))
if(choice)
myself->options |= OPTION_INDIRECT;
if(get_config_bool(lookup_config(config_tree, "TCPOnly"), &choice))
if(choice)
myself->options |= OPTION_TCPONLY;
if(get_config_bool(lookup_config(myself->connection->config_tree, "IndirectData"), &choice))
if(choice)
myself->options |= OPTION_INDIRECT;
if(get_config_bool(lookup_config(myself->connection->config_tree, "TCPOnly"), &choice))
if(choice)
myself->options |= OPTION_TCPONLY;
if(myself->options & OPTION_TCPONLY)
myself->options |= OPTION_INDIRECT;
if(get_config_string(lookup_config(config_tree, "Mode"), &mode))
{
if(!strcasecmp(mode, "router"))
routing_mode = RMODE_ROUTER;
else if (!strcasecmp(mode, "switch"))
routing_mode = RMODE_SWITCH;
else if (!strcasecmp(mode, "hub"))
routing_mode = RMODE_HUB;
else
{
syslog(LOG_ERR, _("Invalid routing mode!"));
return -1;
}
}
else
routing_mode = RMODE_ROUTER;
cp
/* Open sockets */
if((tcp_socket = setup_listen_socket(myself->port)) < 0)
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{
syslog(LOG_ERR, _("Unable to set up a listening TCP socket!"));
return -1;
}
if((udp_socket = setup_vpn_in_socket(myself->port)) < 0)
{
syslog(LOG_ERR, _("Unable to set up a listening UDP socket!"));
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return -1;
}
cp
/* Generate packet encryption key */
myself->cipher = EVP_bf_cbc();
myself->keylength = myself->cipher->key_len + myself->cipher->iv_len;
myself->key = (char *)xmalloc(myself->keylength);
RAND_pseudo_bytes(myself->key, myself->keylength);
if(!get_config_int(lookup_config(config_tree, "KeyExpire"), &keylifetime))
keylifetime = 3600;
keyexpires = time(NULL) + keylifetime;
cp
/* Done */
myself->nexthop = myself;
myself->via = myself;
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myself->status.active = 1;
node_add(myself);
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syslog(LOG_NOTICE, _("Ready: listening on port %hd"), myself->port);
cp
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return 0;
}
/*
setup all initial network connections
*/
int setup_network_connections(void)
{
cp
init_connections();
init_subnets();
init_nodes();
if(get_config_int(lookup_config(config_tree, "PingTimeout"), &timeout))
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{
if(timeout < 1)
{
timeout = 86400;
}
}
else
timeout = 60;
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if(setup_device() < 0)
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return -1;
/* Run tinc-up script to further initialize the tap interface */
execute_script("tinc-up");
if(setup_myself() < 0)
return -1;
signal(SIGALRM, try_outgoing_connections);
alarm(5);
cp
return 0;
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}
/*
close all open network connections
*/
void close_network_connections(void)
{
avl_node_t *node, *next;
connection_t *c;
cp
for(node = connection_tree->head; node; node = next)
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{
next = node->next;
c = (connection_t *)node->data;
c->status.outgoing = 0;
terminate_connection(c, 0);
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}
// terminate_connection(myself, 0);
// destroy_trees();
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execute_script("tinc-down");
close_device();
cp
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return;
}
/*
handle an incoming tcp connect call and open
a connection to it.
*/
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connection_t *create_new_connection(int sfd)
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{
connection_t *c;
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struct sockaddr_in ci;
int len = sizeof(ci);
cp
c = new_connection();
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if(getpeername(sfd, (struct sockaddr *) &ci, (socklen_t *) &len) < 0)
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{
syslog(LOG_ERR, _("System call `%s' failed: %m"),
"getpeername");
close(sfd);
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return NULL;
}
c->address = ntohl(ci.sin_addr.s_addr);
c->hostname = hostlookup(ci.sin_addr.s_addr);
c->port = htons(ci.sin_port); /* This one will be overwritten later */
c->socket = sfd;
c->last_ping_time = time(NULL);
if(debug_lvl >= DEBUG_CONNECTIONS)
syslog(LOG_NOTICE, _("Connection from %s port %d"),
c->hostname, htons(ci.sin_port));
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c->allow_request = ID;
cp
return c;
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}
/*
put all file descriptors in an fd_set array
*/
void build_fdset(fd_set *fs)
{
avl_node_t *node;
connection_t *c;
cp
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FD_ZERO(fs);
for(node = connection_tree->head; node; node = node->next)
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{
c = (connection_t *)node->data;
FD_SET(c->socket, fs);
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}
FD_SET(tcp_socket, fs);
FD_SET(udp_socket, fs);
FD_SET(device_fd, fs);
cp
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}
/*
receive incoming data from the listening
udp socket and write it to the ethertap
device after being decrypted
*/
void handle_incoming_vpn_data(void)
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{
vpn_packet_t pkt;
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int x, l = sizeof(x);
struct sockaddr_in from;
socklen_t fromlen = sizeof(from);
node_t *n;
cp
if(getsockopt(udp_socket, SOL_SOCKET, SO_ERROR, &x, &l) < 0)
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{
syslog(LOG_ERR, _("This is a bug: %s:%d: %d:%m"),
__FILE__, __LINE__, udp_socket);
return;
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}
if(x)
{
syslog(LOG_ERR, _("Incoming data socket error: %s"), strerror(x));
return;
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}
if((pkt.len = recvfrom(udp_socket, (char *) pkt.salt, MTU, 0, (struct sockaddr *)&from, &fromlen)) <= 0)
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{
syslog(LOG_ERR, _("Receiving packet failed: %m"));
return;
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}
n = lookup_node_udp(ntohl(from.sin_addr.s_addr), ntohs(from.sin_port));
if(!n)
{
syslog(LOG_WARNING, _("Received UDP packets on port %hd from unknown source %x:%hd"), myself->port, ntohl(from.sin_addr.s_addr), ntohs(from.sin_port));
return;
}
/*
if(n->connection)
n->connection->last_ping_time = time(NULL);
*/
receive_udppacket(n, &pkt);
cp
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}
/*
Terminate a connection:
- Close the sockets
- Remove associated hosts and subnets
- Deactivate the host
- Since it might still be referenced, put it on the prune list.
- If report == 1, then send DEL_HOST messages to the other tinc daemons.
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*/
void terminate_connection(connection_t *c, int report)
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{
/* Needs a serious rewrite. */
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}
/*
Check if the other end is active.
If we have sent packets, but didn't receive any,
then possibly the other end is dead. We send a
PING request over the meta connection. If the other
end does not reply in time, we consider them dead
and close the connection.
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*/
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void check_dead_connections(void)
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{
time_t now;
avl_node_t *node, *next;
connection_t *c;
cp
now = time(NULL);
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for(node = connection_tree->head; node; node = next)
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{
next = node->next;
c = (connection_t *)node->data;
if(c->last_ping_time + timeout < now)
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{
if(c->status.active)
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{
if(c->status.pinged)
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{
if(debug_lvl >= DEBUG_PROTOCOL)
syslog(LOG_INFO, _("%s (%s) didn't respond to PING"),
c->name, c->hostname);
c->status.timeout = 1;
terminate_connection(c, 1);
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}
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else
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{
send_ping(c);
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}
}
else
{
if(debug_lvl >= DEBUG_CONNECTIONS)
syslog(LOG_WARNING, _("Timeout from %s (%s) during authentication"),
c->name, c->hostname);
terminate_connection(c, 0);
}
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}
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}
cp
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}
/*
accept a new tcp connect and create a
new connection
*/
int handle_new_meta_connection()
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{
connection_t *new;
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struct sockaddr client;
int fd, len = sizeof(client);
cp
if((fd = accept(tcp_socket, &client, &len)) < 0)
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{
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syslog(LOG_ERR, _("Accepting a new connection failed: %m"));
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return -1;
}
if(!(new = create_new_connection(fd)))
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{
shutdown(fd, 2);
close(fd);
syslog(LOG_NOTICE, _("Closed attempted connection"));
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return 0;
}
connection_add(new);
send_id(new);
cp
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return 0;
}
void randomized_alarm(int seconds)
{
unsigned char r;
RAND_pseudo_bytes(&r, 1);
alarm((seconds * (int)r) / 128 + 1);
}
/* This function is severely fucked up.
We want to redesign it so the following rules apply:
- Try all ConnectTo's in a row:
- if a connect() fails, try next one immediately,
- if it works, wait 5 seconds or so.
- If none of them were succesful, increase delay and retry.
- If all were succesful, don't try anymore.
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*/
RETSIGTYPE
try_outgoing_connections(int a)
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{
static config_t *cfg = NULL;
static int retry = 0;
char *name;
cp
if(!cfg)
cfg = lookup_config(config_tree, "ConnectTo");
if(!cfg)
return;
while(cfg)
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{
get_config_string(cfg, &name);
cfg = lookup_config_next(config_tree, cfg); /* Next time skip to next ConnectTo line */
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if(!setup_outgoing_connection(name)) /* function returns 0 when there are no problems */
retry = 1;
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}
get_config_int(lookup_config(config_tree, "MaxTimeout"), &maxtimeout);
if(retry)
{
seconds_till_retry += 5;
if(seconds_till_retry > maxtimeout) /* Don't wait more than MAXTIMEOUT seconds. */
seconds_till_retry = maxtimeout;
syslog(LOG_ERR, _("Failed to setup all outgoing connections, will retry in %d seconds"),
seconds_till_retry);
/* Randomize timeout to avoid global synchronisation effects */
randomized_alarm(seconds_till_retry);
}
else
{
seconds_till_retry = 5;
}
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cp
}
/*
check all connections to see if anything
happened on their sockets
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*/
void check_network_activity(fd_set *f)
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{
connection_t *c;
avl_node_t *node;
cp
if(FD_ISSET(udp_socket, f))
handle_incoming_vpn_data();
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for(node = connection_tree->head; node; node = node->next)
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{
c = (connection_t *)node->data;
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if(c->status.remove)
return;
if(FD_ISSET(c->socket, f))
if(receive_meta(c) < 0)
{
terminate_connection(c, c->status.active);
return;
}
}
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if(FD_ISSET(tcp_socket, f))
handle_new_meta_connection();
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cp
}
/*
this is where it all happens...
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*/
void main_loop(void)
{
fd_set fset;
struct timeval tv;
int r;
time_t last_ping_check;
int t;
2001-10-27 13:13:35 +00:00
vpn_packet_t packet;
cp
last_ping_check = time(NULL);
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for(;;)
{
tv.tv_sec = timeout;
tv.tv_usec = 0;
build_fdset(&fset);
if((r = select(FD_SETSIZE, &fset, NULL, NULL, &tv)) < 0)
{
if(errno != EINTR) /* because of alarm */
{
syslog(LOG_ERR, _("Error while waiting for input: %m"));
return;
}
}
if(sighup)
{
syslog(LOG_INFO, _("Rereading configuration file and restarting in 5 seconds"));
sighup = 0;
close_network_connections();
exit_configuration(&config_tree);
if(read_server_config())
{
syslog(LOG_ERR, _("Unable to reread configuration file, exiting"));
2001-03-01 21:32:04 +00:00
exit(1);
}
sleep(5);
if(setup_network_connections())
return;
continue;
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}
t = time(NULL);
/* Let's check if everybody is still alive */
if(last_ping_check + timeout < t)
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{
check_dead_connections();
last_ping_check = time(NULL);
/* Should we regenerate our key? */
if(keyexpires < t)
{
if(debug_lvl >= DEBUG_STATUS)
syslog(LOG_INFO, _("Regenerating symmetric key"));
RAND_pseudo_bytes(myself->key, myself->keylength);
send_key_changed(myself->connection, myself);
keyexpires = time(NULL) + keylifetime;
}
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}
if(r > 0)
{
check_network_activity(&fset);
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/* local tap data */
if(FD_ISSET(device_fd, &fset))
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{
if(read_packet(&packet))
route_outgoing(&packet);
else
return;
}
}
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}
cp
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}