/*
protocol.c -- handle the meta-protocol
- Copyright (C) 1999,2000 Ivo Timmermans <itimmermans@bigfoot.com>,
- 2000 Guus Sliepen <guus@sliepen.warande.net>
+ Copyright (C) 1999-2001 Ivo Timmermans <itimmermans@bigfoot.com>,
+ 2000,2001 Guus Sliepen <guus@sliepen.warande.net>
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
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- $Id: protocol.c,v 1.28.4.45 2000/10/24 15:46:17 guus Exp $
+ $Id: protocol.c,v 1.28.4.108 2001/10/08 15:37:14 guus Exp $
*/
#include "config.h"
#include <sys/socket.h>
#include <unistd.h>
#include <stdio.h>
+#include <stdarg.h>
+#include <errno.h>
#include <utils.h>
#include <xalloc.h>
+#include <avl_tree.h>
+#include <list.h>
#include <netinet/in.h>
#include <openssl/sha.h>
+#include <openssl/rand.h>
+#include <openssl/evp.h>
+
+#ifndef HAVE_RAND_PSEUDO_BYTES
+#define RAND_pseudo_bytes RAND_bytes
+#endif
#include "conf.h"
-#include "encr.h"
#include "net.h"
#include "netutl.h"
#include "protocol.h"
#include "meta.h"
+#include "connection.h"
#include "system.h"
+int mykeyused = 0;
+
int check_id(char *id)
{
int i;
for (i = 0; i < strlen(id); i++)
if(!isalnum(id[i]) && id[i] != '_')
return -1;
-
+
return 0;
}
-/* Generic request routines - takes care of logging and error detection as well */
+/* Generic request routines - takes care of logging and error
+ detection as well */
-int send_request(conn_list_t *cl, const char *format, ...)
+int send_request(connection_t *cl, const char *format, ...)
{
va_list args;
char buffer[MAXBUFSIZE];
int len, request;
cp
- /* Use vsnprintf instead of vasprintf: faster, no memory fragmentation, cleanup is automatic,
- and there is a limit on the input buffer anyway */
+ /* Use vsnprintf instead of vasprintf: faster, no memory
+ fragmentation, cleanup is automatic, and there is a limit on the
+ input buffer anyway */
va_start(args, format);
len = vsnprintf(buffer, MAXBUFSIZE, format, args);
return -1;
}
- len++;
-
if(debug_lvl >= DEBUG_PROTOCOL)
- syslog(LOG_DEBUG, _("Sending %s to %s (%s)"), request_name[request], cl->name, cl->hostname);
+ {
+ if(debug_lvl >= DEBUG_META)
+ syslog(LOG_DEBUG, _("Sending %s to %s (%s): %s"), request_name[request], cl->name, cl->hostname, buffer);
+ else
+ syslog(LOG_DEBUG, _("Sending %s to %s (%s)"), request_name[request], cl->name, cl->hostname);
+ }
+ buffer[len++] = '\n';
cp
return send_meta(cl, buffer, len);
}
-int receive_request(conn_list_t *cl)
+int receive_request(connection_t *cl)
{
int request;
-cp
+cp
if(sscanf(cl->buffer, "%d", &request) == 1)
{
- if((request < 0) || (request > 255) || (request_handlers[request] == NULL))
+ if((request < 0) || (request >= LAST) || (request_handlers[request] == NULL))
{
- syslog(LOG_ERR, _("Unknown request from %s (%s)"),
- cl->name, cl->hostname);
+ if(debug_lvl >= DEBUG_META)
+ syslog(LOG_DEBUG, _("Unknown request from %s (%s): %s"),
+ cl->name, cl->hostname, cl->buffer);
+ else
+ syslog(LOG_ERR, _("Unknown request from %s (%s)"),
+ cl->name, cl->hostname);
+
return -1;
}
else
{
if(debug_lvl >= DEBUG_PROTOCOL)
- syslog(LOG_DEBUG, _("Got %s from %s (%s)"),
- request_name[request], cl->name, cl->hostname);
+ {
+ if(debug_lvl >= DEBUG_META)
+ syslog(LOG_DEBUG, _("Got %s from %s (%s): %s"),
+ request_name[request], cl->name, cl->hostname, cl->buffer);
+ else
+ syslog(LOG_DEBUG, _("Got %s from %s (%s)"),
+ request_name[request], cl->name, cl->hostname);
+ }
}
+
+ if((cl->allow_request != ALL) && (cl->allow_request != request))
+ {
+ syslog(LOG_ERR, _("Unauthorized request from %s (%s)"), cl->name, cl->hostname);
+ return -1;
+ }
+
if(request_handlers[request](cl))
/* Something went wrong. Probably scriptkiddies. Terminate. */
{
cl->name, cl->hostname);
return -1;
}
+cp
+ return 0;
}
-/* Connection protocol:
-
- Client Server
- send_id(u)
- send_challenge(R)
- send_chal_reply(H)
- send_id(u)
- send_challenge(R)
- send_chal_reply(H)
- ---------------------------------------
- Any negotations about the meta protocol
- encryption go here(u).
- ---------------------------------------
- send_ack(u)
- send_ack(u)
- ---------------------------------------
- Other requests(E)...
-
- (u) Unencrypted,
- (R) RSA,
- (H) SHA1,
- (E) Encrypted with symmetric cipher.
-
- Part of the challenge is directly used to set the symmetric cipher key and the initial vector.
- Since a man-in-the-middle cannot decrypt the RSA challenges, this means that he cannot get or
- forge the key for the symmetric cipher.
-*/
+/* The authentication protocol is described in detail in doc/SECURITY2,
+ the rest will be described in doc/PROTOCOL. */
-int send_id(conn_list_t *cl)
+int send_id(connection_t *cl)
{
-cp
- cl->allow_request = CHALLENGE;
cp
return send_request(cl, "%d %s %d %lx %hd", ID, myself->name, myself->protocol_version, myself->options, myself->port);
}
-int id_h(conn_list_t *cl)
+int id_h(connection_t *cl)
{
- conn_list_t *old;
- config_t *cfg;
+ char name[MAX_STRING_SIZE];
cp
- if(sscanf(cl->buffer, "%*d %as %d %lx %hd", &cl->name, &cl->protocol_version, &cl->options, &cl->port) != 4)
+ if(sscanf(cl->buffer, "%*d "MAX_STRING" %d %lx %hd", name, &cl->protocol_version, &cl->options, &cl->port) != 4)
{
syslog(LOG_ERR, _("Got bad ID from %s"), cl->hostname);
return -1;
/* Check if identity is a valid name */
- if(check_id(cl->name))
+ if(check_id(name))
{
syslog(LOG_ERR, _("Peer %s uses invalid identity name"), cl->hostname);
return -1;
}
+
+ /* Copy string to cl */
+
+ if(cl->name)
+ free(cl->name);
+
+ cl->name = xstrdup(name);
/* Load information about peer */
-cp
+
if(read_host_config(cl))
{
syslog(LOG_ERR, _("Peer %s had unknown identity (%s)"), cl->hostname, cl->name);
return -1;
}
- /* First check if the host we connected to is already in our
- connection list. If so, we are probably making a loop, which
- is not desirable.
- */
+ /* Read in the public key, so that we can send a metakey */
+
+ if(read_rsa_public_key(cl))
+ return -1;
+
+ cl->allow_request = METAKEY;
cp
- if(cl->status.outgoing)
+ return send_metakey(cl);
+}
+
+int ack_h(connection_t *cl)
+{
+ config_t const *cfg;
+ connection_t *old, *p;
+ subnet_t *subnet;
+ avl_node_t *node, *node2;
+cp
+ /* Okay, before we active the connection, we check if there is another entry
+ in the connection list with the same name. If so, it presumably is an
+ old connection that has timed out but we don't know it yet.
+ */
+
+ if((old = lookup_id(cl->name)))
{
- if((old = lookup_id(cl->name)))
+ if(debug_lvl >= DEBUG_CONNECTIONS)
+ syslog(LOG_NOTICE, _("Removing old connection for %s at %s in favour of new connection at %s"),
+ old->name, old->hostname, cl->hostname);
+ if(old->status.outgoing)
{
- if(debug_lvl >= DEBUG_CONNECTIONS)
- syslog(LOG_NOTICE, _("Uplink %s (%s) is already in our connection list"), cl->name, cl->hostname);
- cl->status.outgoing = 0;
- old->status.outgoing = 1;
- terminate_connection(cl);
- return 0;
+ cl->status.outgoing = 1;
+ old->status.outgoing = 0;
}
+
+ terminate_connection(old, 0);
}
-cp
- if(!(cfg = get_config_val(cl->config, publickey)))
+
+ /* Also check if no other tinc daemon uses the same IP and port for UDP traffic */
+
+ old = avl_search(active_tree, cl);
+ if(old)
+ {
+ syslog(LOG_ERR, _("%s is listening on %s:%hd, which is already in use by %s!"),
+ cl->name, cl->hostname, cl->port, old->name);
+ return -1;
+ }
+
+ /* Activate this connection */
+
+ cl->allow_request = ALL;
+ cl->nexthop = cl;
+ cl->prevhop = myself;
+ cl->cipher_pkttype = EVP_bf_cbc();
+ cl->cipher_pktkeylength = cl->cipher_pkttype->key_len + cl->cipher_pkttype->iv_len;
+
+ active_add(cl);
+
+ if(debug_lvl >= DEBUG_CONNECTIONS)
+ syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), cl->name, cl->hostname);
+
+ if(cl->status.outgoing)
+ seconds_till_retry = 5; /* Reset retry timeout */
+cp
+ /* Check some options */
+
+ if((cfg = get_config_val(cl->config, config_indirectdata)))
{
- syslog(LOG_ERR, _("No public key known for %s (%s)"), cl->name, cl->hostname);
- return -1;
+ if(cfg->data.val == stupid_true)
+ cl->options |= OPTION_INDIRECT;
+ }
+
+ if((cfg = get_config_val(cl->config, config_tcponly)))
+ {
+ if(cfg->data.val == stupid_true)
+ cl->options |= OPTION_TCPONLY;
}
+
+ if((myself->options | cl->options) & OPTION_INDIRECT)
+ cl->via = myself;
else
+ cl->via = cl;
+
+ /* Send him our subnets */
+
+ for(node = myself->subnet_tree->head; node; node = node->next)
{
-cp
- cl->rsa_key = RSA_new();
- BN_hex2bn(&cl->rsa_key->n, cfg->data.ptr);
- BN_hex2bn(&cl->rsa_key->e, "FFFF");
+ subnet = (subnet_t *)node->data;
+ send_add_subnet(cl, subnet);
}
+ /* And send him all the hosts and their subnets we know... */
+
+ for(node = active_tree->head; node; node = node->next)
+ {
+ p = (connection_t *)node->data;
+
+ if(p != cl)
+ {
+ /* Notify others of this connection */
+
+ if(p->status.meta)
+ send_add_host(p, cl);
+
+ /* Notify new connection of everything we know */
+
+ send_add_host(cl, p);
+
+ for(node2 = p->subnet_tree->head; node2; node2 = node2->next)
+ {
+ subnet = (subnet_t *)node2->data;
+ send_add_subnet(cl, subnet);
+ }
+ }
+ }
cp
- return send_challenge(cl);
+ return 0;
}
-int send_challenge(conn_list_t *cl)
+int send_challenge(connection_t *cl)
{
char *buffer;
int len, x;
cp
+ /* CHECKME: what is most reasonable value for len? */
+
len = RSA_size(cl->rsa_key);
/* Allocate buffers for the challenge */
cl->hischallenge = xmalloc(len);
cp
- /* Seed the PRNG with urandom (can't afford to block) */
-
- RAND_load_file("/dev/urandom", 1024);
-
/* Copy random data to the buffer */
RAND_bytes(cl->hischallenge, len);
- cl->hischallenge[0] &= 0x7F; /* Somehow if the first byte is more than 0xD0 or something like that, decryption fails... */
-
- if(debug_lvl >= DEBUG_SCARY_THINGS)
- {
- bin2hex(cl->hischallenge, buffer, len);
- buffer[len*2] = '\0';
- syslog(LOG_DEBUG, _("Generated random challenge (unencrypted): %s"), buffer);
- }
-
- /* Encrypt the random data */
-
- if(RSA_public_encrypt(len, cl->hischallenge, buffer, cl->rsa_key, RSA_NO_PADDING) != len) /* NO_PADDING because the message size equals the RSA key size and it is totally random */
- {
- syslog(LOG_ERR, _("Error during encryption of challenge for %s (%s)"), cl->name, cl->hostname);
- free(buffer);
- return -1;
- }
cp
- /* Convert the encrypted random data to a hexadecimal formatted string */
+ /* Convert to hex */
- bin2hex(buffer, buffer, len);
+ bin2hex(cl->hischallenge, buffer, len);
buffer[len*2] = '\0';
+cp
/* Send the challenge */
- cl->allow_request = CHAL_REPLY;
x = send_request(cl, "%d %s", CHALLENGE, buffer);
free(buffer);
cp
return x;
}
-int challenge_h(conn_list_t *cl)
+int challenge_h(connection_t *cl)
{
- char *buffer;
+ char buffer[MAX_STRING_SIZE];
int len;
cp
- if(sscanf(cl->buffer, "%*d %as", &buffer) != 1)
+ if(sscanf(cl->buffer, "%*d "MAX_STRING, buffer) != 1)
{
syslog(LOG_ERR, _("Got bad CHALLENGE from %s (%s)"), cl->name, cl->hostname);
return -1;
if(strlen(buffer) != len*2)
{
syslog(LOG_ERR, _("Intruder: wrong challenge length from %s (%s)"), cl->name, cl->hostname);
- free(buffer);
return -1;
}
/* Convert the challenge from hexadecimal back to binary */
- hex2bin(buffer,buffer,len);
-
- /* Decrypt the challenge */
-
- if(RSA_private_decrypt(len, buffer, cl->mychallenge, myself->rsa_key, RSA_NO_PADDING) != len) /* See challenge() */
- {
- syslog(LOG_ERR, _("Error during encryption of challenge for %s (%s)"), cl->name, cl->hostname);
- free(buffer);
- return -1;
- }
+ hex2bin(buffer,cl->mychallenge,len);
- if(debug_lvl >= DEBUG_SCARY_THINGS)
- {
- bin2hex(cl->mychallenge, buffer, len);
- buffer[len*2] = '\0';
- syslog(LOG_DEBUG, _("Received random challenge (unencrypted): %s"), buffer);
- }
+ cl->allow_request = CHAL_REPLY;
- free(buffer);
-
/* Rest is done by send_chal_reply() */
cp
return send_chal_reply(cl);
}
-int send_chal_reply(conn_list_t *cl)
+int send_chal_reply(connection_t *cl)
{
char hash[SHA_DIGEST_LENGTH*2+1];
cp
/* Send the reply */
- if(cl->status.outgoing)
- cl->allow_request = ID;
- else
- cl->allow_request = ACK;
-
cp
return send_request(cl, "%d %s", CHAL_REPLY, hash);
}
-int chal_reply_h(conn_list_t *cl)
+int chal_reply_h(connection_t *cl)
{
- char *hishash;
+ char hishash[MAX_STRING_SIZE];
char myhash[SHA_DIGEST_LENGTH];
cp
- if(sscanf(cl->buffer, "%*d %as", &hishash) != 1)
+ if(sscanf(cl->buffer, "%*d "MAX_STRING, hishash) != 1)
{
syslog(LOG_ERR, _("Got bad CHAL_REPLY from %s (%s)"), cl->name, cl->hostname);
- free(hishash);
return -1;
}
if(strlen(hishash) != SHA_DIGEST_LENGTH*2)
{
syslog(LOG_ERR, _("Intruder: wrong challenge reply length from %s (%s)"), cl->name, cl->hostname);
- free(hishash);
return -1;
}
hishash[SHA_DIGEST_LENGTH*2] = '\0';
syslog(LOG_DEBUG, _("Expected challenge reply: %s"), hishash);
}
- free(hishash);
return -1;
}
-
- free(hishash);
-
/* Identity has now been positively verified.
- If we are accepting this new connection, then send our identity,
- if we are making this connecting, acknowledge.
+ ack_h() handles the rest from now on.
*/
cp
- if(cl->status.outgoing)
- return send_ack(cl);
- else
- return send_id(cl);
+ return ack_h(cl);
}
-int send_ack(conn_list_t *cl)
+int send_metakey(connection_t *cl)
{
+ char *buffer;
+ int len, x;
+cp
+ len = RSA_size(cl->rsa_key);
+
+ /* Allocate buffers for the meta key */
+
+ buffer = xmalloc(len*2+1);
+
+ if(!cl->cipher_outkey)
+ cl->cipher_outkey = xmalloc(len);
+
+ if(!cl->cipher_outctx)
+ cl->cipher_outctx = xmalloc(sizeof(*cl->cipher_outctx));
cp
- cl->allow_request = ACK;
+ /* Copy random data to the buffer */
+
+ RAND_bytes(cl->cipher_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:
+
+ 2^(k-1) <= modulus < 2^(k)
+
+ Where ^ means "to the power of", not "xor".
+ This means that to be sure, we must choose our message < 2^(k-1).
+ This can be done by setting the most significant bit to zero.
+ */
+
+ cl->cipher_outkey[0] &= 0x7F;
+
+ if(debug_lvl >= DEBUG_SCARY_THINGS)
+ {
+ bin2hex(cl->cipher_outkey, buffer, len);
+ buffer[len*2] = '\0';
+ syslog(LOG_DEBUG, _("Generated random meta key (unencrypted): %s"), buffer);
+ }
+
+ /* Encrypt the random data
+
+ We do not use one of the PKCS padding schemes here.
+ This is allowed, because we encrypt a totally random string
+ with a length equal to that of the modulus of the RSA key.
+ */
+
+ if(RSA_public_encrypt(len, cl->cipher_outkey, buffer, cl->rsa_key, RSA_NO_PADDING) != len)
+ {
+ syslog(LOG_ERR, _("Error during encryption of meta key for %s (%s)"), cl->name, cl->hostname);
+ free(buffer);
+ return -1;
+ }
cp
- return send_request(cl, "%d", ACK);
+ /* Convert the encrypted random data to a hexadecimal formatted string */
+
+ bin2hex(buffer, buffer, len);
+ buffer[len*2] = '\0';
+
+ /* Send the meta key */
+
+ x = send_request(cl, "%d %s", METAKEY, buffer);
+ free(buffer);
+
+ /* Further outgoing requests are encrypted with the key we just generated */
+
+ EVP_EncryptInit(cl->cipher_outctx, EVP_bf_cfb(),
+ cl->cipher_outkey + len - EVP_bf_cfb()->key_len,
+ cl->cipher_outkey + len - EVP_bf_cfb()->key_len - EVP_bf_cfb()->iv_len);
+
+ cl->status.encryptout = 1;
+cp
+ return x;
}
-int ack_h(conn_list_t *cl)
+int metakey_h(connection_t *cl)
{
- conn_list_t *old;
+ char buffer[MAX_STRING_SIZE];
+ int len;
cp
- /* Okay, before we active the connection, we check if there is another entry
- in the connection list with the same name. If so, it presumably is an
- old connection that has timed out but we don't know it yet.
- */
+ if(sscanf(cl->buffer, "%*d "MAX_STRING, buffer) != 1)
+ {
+ syslog(LOG_ERR, _("Got bad METAKEY from %s (%s)"), cl->name, cl->hostname);
+ return -1;
+ }
- while((old = lookup_id(cl->name)))
+ len = RSA_size(myself->rsa_key);
+
+ /* Check if the length of the meta key is all right */
+
+ if(strlen(buffer) != len*2)
{
- if(debug_lvl >= DEBUG_CONNECTIONS)
- syslog(LOG_NOTICE, _("Removing old entry for %s at %s in favour of new connection from %s"),
- cl->name, old->hostname, cl->hostname);
- old->status.active = 0;
- terminate_connection(old);
+ syslog(LOG_ERR, _("Intruder: wrong meta key length from %s (%s)"), cl->name, cl->hostname);
+ return -1;
}
- /* Activate this connection */
+ /* Allocate buffers for the meta key */
- cl->allow_request = ALL;
- cl->status.active = 1;
+ if(!cl->cipher_inkey)
+ cl->cipher_inkey = xmalloc(len);
- if(debug_lvl >= DEBUG_CONNECTIONS)
- syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), cl->name, cl->hostname);
+ if(!cl->cipher_inctx)
+ cl->cipher_inctx = xmalloc(sizeof(*cl->cipher_inctx));
- /* Exchange information about other tinc daemons */
+ /* Convert the challenge from hexadecimal back to binary */
-/* FIXME: reprogram this.
- notify_others(cl, NULL, send_add_host);
- notify_one(cl);
-*/
+ hex2bin(buffer,buffer,len);
+
+ /* Decrypt the meta key */
+
+ if(RSA_private_decrypt(len, buffer, cl->cipher_inkey, myself->rsa_key, RSA_NO_PADDING) != len) /* See challenge() */
+ {
+ syslog(LOG_ERR, _("Error during encryption of meta key for %s (%s)"), cl->name, cl->hostname);
+ return -1;
+ }
+ if(debug_lvl >= DEBUG_SCARY_THINGS)
+ {
+ bin2hex(cl->cipher_inkey, buffer, len);
+ buffer[len*2] = '\0';
+ syslog(LOG_DEBUG, _("Received random meta key (unencrypted): %s"), buffer);
+ }
+
+ /* All incoming requests will now be encrypted. */
+
+ EVP_DecryptInit(cl->cipher_inctx, EVP_bf_cfb(),
+ cl->cipher_inkey + len - EVP_bf_cfb()->key_len,
+ cl->cipher_inkey + len - EVP_bf_cfb()->key_len - EVP_bf_cfb()->iv_len);
+
+ cl->status.decryptin = 1;
+
+ cl->allow_request = CHALLENGE;
cp
- if(cl->status.outgoing)
- return 0;
- else
- return send_ack(cl);
+ return send_challenge(cl);
}
/* Address and subnet information exchange */
-int send_add_subnet(conn_list_t *cl, conn_list_t *other, subnet_t *subnet)
+int send_add_subnet(connection_t *cl, subnet_t *subnet)
{
int x;
char *netstr;
+ char *owner;
cp
+ owner = subnet->owner->name;
+
x = send_request(cl, "%d %s %s", ADD_SUBNET,
- other->name, netstr = net2str(subnet));
+ owner, netstr = net2str(subnet));
free(netstr);
cp
return x;
}
-int add_subnet_h(conn_list_t *cl)
+int add_subnet_h(connection_t *cl)
{
- char *subnetstr;
- char *name;
- conn_list_t *owner;
- subnet_t *subnet, *old;
+ char subnetstr[MAX_STRING_SIZE];
+ char name[MAX_STRING_SIZE];
+ connection_t *owner, *p;
+ subnet_t *subnet;
+ avl_node_t *node;
cp
- if(sscanf(cl->buffer, "%*d %as %as", &name, &subnetstr) != 3)
+ if(sscanf(cl->buffer, "%*d "MAX_STRING" "MAX_STRING, name, subnetstr) != 2)
{
syslog(LOG_ERR, _("Got bad ADD_SUBNET from %s (%s)"), cl->name, cl->hostname);
- free(name); free(subnetstr);
return -1;
}
if(check_id(name))
{
syslog(LOG_ERR, _("Got bad ADD_SUBNET from %s (%s): invalid identity name"), cl->name, cl->hostname);
- free(name); free(subnetstr);
return -1;
}
if(!(subnet = str2net(subnetstr)))
{
syslog(LOG_ERR, _("Got bad ADD_SUBNET from %s (%s): invalid subnet string"), cl->name, cl->hostname);
- free(name); free(subnetstr);
return -1;
}
- free(subnetstr);
-
/* Check if somebody tries to add a subnet of ourself */
if(!strcmp(name, myself->name))
{
syslog(LOG_ERR, _("Warning: got ADD_SUBNET from %s (%s) for ourself, restarting"),
cl->name, cl->hostname);
- free(name);
sighup = 1;
return 0;
}
{
syslog(LOG_ERR, _("Got ADD_SUBNET for %s from %s (%s) which is not in our connection list"),
name, cl->name, cl->hostname);
- free(name);
return -1;
}
/* If everything is correct, add the subnet to the list of the owner */
subnet_add(owner, subnet);
+
+ /* Tell the rest */
+
+ for(node = connection_tree->head; node; node = node->next)
+ {
+ p = (connection_t *)node->data;
+ if(p->status.active && p!= cl)
+ send_add_subnet(p, subnet);
+ }
cp
return 0;
}
-int send_del_subnet(conn_list_t *cl, conn_list_t *other, subnet_t *subnet)
+int send_del_subnet(connection_t *cl, subnet_t *subnet)
{
+ int x;
+ char *netstr;
+ char *owner;
+cp
+ owner = subnet->owner->name;
+
+ x = send_request(cl, "%d %s %s", DEL_SUBNET, owner, netstr = net2str(subnet));
+ free(netstr);
cp
- return send_request(cl, "%d %s %s", DEL_SUBNET, other->name, net2str(subnet));
+ return x;
}
-int del_subnet_h(conn_list_t *cl)
+int del_subnet_h(connection_t *cl)
{
- char *subnetstr;
- char *name;
- conn_list_t *owner;
- subnet_t *subnet, *old;
+ char subnetstr[MAX_STRING_SIZE];
+ char name[MAX_STRING_SIZE];
+ connection_t *owner, *p;
+ subnet_t *subnet;
+ avl_node_t *node;
cp
- if(sscanf(cl->buffer, "%*d %as %as", &name, &subnetstr) != 3)
+ if(sscanf(cl->buffer, "%*d "MAX_STRING" "MAX_STRING, name, subnetstr) != 3)
{
syslog(LOG_ERR, _("Got bad DEL_SUBNET from %s (%s)"), cl->name, cl->hostname);
- free(name); free(subnetstr);
return -1;
}
if(check_id(name))
{
syslog(LOG_ERR, _("Got bad DEL_SUBNET from %s (%s): invalid identity name"), cl->name, cl->hostname);
- free(name); free(subnetstr);
return -1;
}
if(!(subnet = str2net(subnetstr)))
{
syslog(LOG_ERR, _("Got bad DEL_SUBNET from %s (%s): invalid subnet string"), cl->name, cl->hostname);
- free(name); free(subnetstr);
return -1;
}
{
syslog(LOG_ERR, _("Warning: got DEL_SUBNET from %s (%s) for ourself, restarting"),
cl->name, cl->hostname);
- free(name);
sighup = 1;
return 0;
}
{
syslog(LOG_ERR, _("Got DEL_SUBNET for %s from %s (%s) which is not in our connection list"),
name, cl->name, cl->hostname);
- free(name);
return -1;
}
/* If everything is correct, delete the subnet from the list of the owner */
subnet_del(subnet);
+
+ /* Tell the rest */
+
+ for(node = connection_tree->head; node; node = node->next)
+ {
+ p = (connection_t *)node->data;
+ if(p->status.active && p!= cl)
+ send_del_subnet(p, subnet);
+ }
cp
return 0;
}
/* New and closed connections notification */
-int send_add_host(conn_list_t *cl, conn_list_t *other)
+int send_add_host(connection_t *cl, connection_t *other)
{
cp
- return send_request(cl, "%d %s %s %lx:%d %lx", ADD_HOST,
- myself->name, other->name, other->address, other->port, other->options);
+ return send_request(cl, "%d %s %lx:%d %lx %s", ADD_HOST,
+ other->name, other->address, other->port, other->options, other->prevhop->name);
}
-int add_host_h(conn_list_t *cl)
+int add_host_h(connection_t *cl)
{
- char *sender;
- conn_list_t *old, *new, *hisuplink;
+ connection_t *old, *new, *p;
+ char name[MAX_STRING_SIZE], prevhop[MAX_STRING_SIZE];
+ avl_node_t *node;
cp
- new = new_conn_list();
+ new = new_connection();
- if(sscanf(cl->buffer, "%*d %as %as %lx:%d %lx", &sender, &new->name, &new->address, &new->port, &new->options) != 5)
+ if(sscanf(cl->buffer, "%*d "MAX_STRING" %lx:%hd %lx "MAX_STRING, name, &new->address, &new->port, &new->options, prevhop) != 5)
{
syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s)"), cl->name, cl->hostname);
return -1;
/* Check if identity is a valid name */
- if(check_id(new->name) || check_id(sender))
+ if(check_id(name))
{
syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s): invalid identity name"), cl->name, cl->hostname);
- free(sender);
+ free_connection(new);
return -1;
}
- /* Check if somebody tries to add ourself */
-
- if(!strcmp(new->name, myself->name))
+ if(check_id(prevhop))
{
- syslog(LOG_ERR, _("Warning: got ADD_HOST from %s (%s) for ourself, restarting"), cl->name, cl->hostname);
- sighup = 1;
- free(sender);
- return 0;
+ syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s): invalid prevhop name"), cl->name, cl->hostname);
+ free_connection(new);
+ return -1;
}
- /* We got an ADD_HOST from ourself!? */
+ /* Check if somebody tries to add ourself */
- if(!strcmp(sender, myself->name))
+ if(!strcmp(name, myself->name))
{
- syslog(LOG_ERR, _("Warning: got ADD_HOST from %s (%s) from ourself, restarting"), cl->name, cl->hostname);
- sighup = 1;
- free(sender);
- return 0;
+ syslog(LOG_ERR, _("Got ADD_HOST from %s (%s) for ourself!"), cl->name, cl->hostname);
+ free_connection(new);
+ return -1;
}
+
+ /* Fill in more of the new connection structure */
- /* Lookup his uplink */
+ new->hostname = hostlookup(htonl(new->address));
- if(!(new->hisuplink = lookup_id(sender)))
+ new->prevhop = lookup_id(prevhop);
+
+ if(!new->prevhop)
{
- syslog(LOG_ERR, _("Got ADD_HOST from %s (%s) with origin %s which is not in our connection list"),
- sender, cl->name, cl->hostname);
- free(sender);
+ syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s): unknown prevhop"), cl->name, cl->hostname);
+ free_connection(new);
return -1;
}
-
- free(sender);
-
- /* Fill in more of the new conn_list structure */
-
- new->hostname = hostlookup(htonl(new->address));
/* Check if the new host already exists in the connnection list */
- if((old = lookup_id(new->name)))
+ if((old = lookup_id(name)))
{
- if((new->address == old->address) && (new->port == old->port))
+ if((new->address == old->address) && (new->port == old->port) && (cl->nexthop == old->nexthop))
{
if(debug_lvl >= DEBUG_CONNECTIONS)
syslog(LOG_NOTICE, _("Got duplicate ADD_HOST for %s (%s) from %s (%s)"),
- old->name, old->hostname, new->name, new->hostname);
+ old->name, old->hostname, cl->name, cl->hostname);
+ free_connection(new);
return 0;
}
else
{
if(debug_lvl >= DEBUG_CONNECTIONS)
- syslog(LOG_NOTICE, _("Removing old entry for %s (%s)"),
- old->name, old->hostname);
- old->status.active = 0;
- terminate_connection(old);
+ syslog(LOG_NOTICE, _("Removing old entry for %s (%s) from %s in favour of new connection from %s"),
+ old->name, old->hostname, old->nexthop->name, cl->nexthop->name);
+
+ terminate_connection(old, 0);
}
}
- /* Fill in rest of conn_list structure */
+ /* Hook it up into the active tree */
- new->myuplink = cl;
- new->status.active = 1;
+ new->name = xstrdup(name);
+ active_add(new);
- /* Hook it up into the conn_list */
+ /* Tell the rest about the new host */
- conn_list_add(conn_list, new);
+ for(node = connection_tree->head; node; node = node->next)
+ {
+ p = (connection_t *)node->data;
+ if(p->status.active && p!=cl)
+ send_add_host(p, new);
+ }
- /* Tell the rest about the new host */
-/* FIXME: reprogram this.
- notify_others(new, cl, send_add_host);
-*/
+ /* Fill in rest of connection structure */
+
+ new->nexthop = cl;
+ new->cipher_pkttype = EVP_bf_cbc();
+ new->cipher_pktkeylength = cl->cipher_pkttype->key_len + cl->cipher_pkttype->iv_len;
+
+ if(new->options & OPTION_INDIRECT || new->prevhop->via != new->prevhop)
+ new->via = new->prevhop->via;
+ else
+ new->via = new;
cp
return 0;
}
-int send_del_host(conn_list_t *cl, conn_list_t *other)
+int send_del_host(connection_t *cl, connection_t *other)
{
cp
- return send_request(cl, "%d %s %s %lx:%d %lx", DEL_HOST,
- myself->name, other->name, other->address, other->port, other->options);
+ return send_request(cl, "%d %s %lx:%d %lx %s", DEL_HOST,
+ other->name, other->address, other->port, other->options, other->prevhop->name);
}
-int del_host_h(conn_list_t *cl)
+int del_host_h(connection_t *cl)
{
- char *name;
- char *sender;
- ip_t address;
+ char name[MAX_STRING_SIZE], prevhop[MAX_STRING_SIZE];
+ ipv4_t address;
port_t port;
- int options;
- conn_list_t *old, *hisuplink;
-
+ long int options;
+ connection_t *old, *p;
+ avl_node_t *node;
cp
- if(sscanf(cl->buffer, "%*d %as %as %lx:%d %lx", &sender, &name, &address, &port, &options) != 5)
+ if(sscanf(cl->buffer, "%*d "MAX_STRING" %lx:%hd %lx "MAX_STRING, name, &address, &port, &options, prevhop) != 5)
{
syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s)"),
cl->name, cl->hostname);
/* Check if identity is a valid name */
- if(check_id(name) || check_id(sender))
+ if(check_id(name))
{
syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s): invalid identity name"), cl->name, cl->hostname);
- free(name); free(sender);
return -1;
}
- /* Check if somebody tries to delete ourself */
-
- if(!strcmp(name, myself->name))
- {
- syslog(LOG_ERR, _("Warning: got DEL_HOST from %s (%s) for ourself, restarting"),
- cl->name, cl->hostname);
- free(name); free(sender);
- sighup = 1;
- return 0;
- }
-
- /* We got an ADD_HOST from ourself!? */
-
- if(!strcmp(sender, myself->name))
+ if(check_id(prevhop))
{
- syslog(LOG_ERR, _("Warning: got DEL_HOST from %s (%s) from ourself, restarting"), cl->name, cl->hostname);
- sighup = 1;
- free(name); free(sender);
- return 0;
+ syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s): invalid prevhop name"), cl->name, cl->hostname);
+ return -1;
}
- /* Lookup his uplink */
+ /* Check if somebody tries to delete ourself */
- if(!(hisuplink = lookup_id(sender)))
+ if(!strcmp(name, myself->name))
{
- syslog(LOG_ERR, _("Got DEL_HOST from %s (%s) with origin %s which is not in our connection list"),
- cl->name, cl->hostname, sender);
- free(name); free(sender);
+ syslog(LOG_ERR, _("Got DEL_HOST from %s (%s) for ourself!"),
+ cl->name, cl->hostname);
return -1;
}
-
- free(sender);
- /* Check if the new host already exists in the connnection list */
+ /* Check if the deleted host already exists in the connnection list */
if(!(old = lookup_id(name)))
{
syslog(LOG_ERR, _("Got DEL_HOST from %s (%s) for %s which is not in our connection list"),
- name, cl->name, cl->hostname);
- free(name);
+ cl->name, cl->hostname, name);
return -1;
}
/* Check if the rest matches */
- if(address!=old->address || port!=old->port || options!=old->options || hisuplink!=old->hisuplink || cl!=old->myuplink)
+ if(address!=old->address || port!=old->port || options!=old->options || cl!=old->nexthop || strcmp(prevhop, old->prevhop->name))
{
syslog(LOG_WARNING, _("Got DEL_HOST from %s (%s) for %s which doesn't match"), cl->name, cl->hostname, old->name);
return 0;
/* Ok, since EVERYTHING seems to check out all right, delete it */
- old->status.termreq = 1;
- old->status.active = 0;
+ terminate_connection(old, 0);
+
+ /* Tell the rest about the deleted host */
- terminate_connection(old);
+ for(node = connection_tree->head; node; node = node->next)
+ {
+ p = (connection_t *)node->data;
+ if(p->status.active && p!=cl)
+ send_del_host(p, old);
+ }
cp
return 0;
}
/* Status and error notification routines */
-int send_status(conn_list_t *cl, int statusno, char *statusstring)
+int send_status(connection_t *cl, int statusno, char *statusstring)
{
cp
if(!statusstring)
return send_request(cl, "%d %d %s", STATUS, statusno, statusstring);
}
-int status_h(conn_list_t *cl)
+int status_h(connection_t *cl)
{
int statusno;
- char *statusstring;
+ char statusstring[MAX_STRING_SIZE];
cp
- if(sscanf(cl->buffer, "%*d %d %as", &statusno, &statusstring) != 2)
+ if(sscanf(cl->buffer, "%*d %d "MAX_STRING, &statusno, statusstring) != 2)
{
syslog(LOG_ERR, _("Got bad STATUS from %s (%s)"),
cl->name, cl->hostname);
}
cp
- free(statusstring);
return 0;
}
-int send_error(conn_list_t *cl, int errno, char *errstring)
+int send_error(connection_t *cl, int err, char *errstring)
{
cp
if(!errstring)
- errstring = strerror(errno);
- return send_request(cl, "%d %d %s", ERROR, errno, errstring);
+ errstring = strerror(err);
+ return send_request(cl, "%d %d %s", ERROR, err, errstring);
}
-int error_h(conn_list_t *cl)
+int error_h(connection_t *cl)
{
- int errno;
- char *errorstring;
+ int err;
+ char errorstring[MAX_STRING_SIZE];
cp
- if(sscanf(cl->buffer, "%*d %d %as", &errno, &errorstring) != 2)
+ if(sscanf(cl->buffer, "%*d %d "MAX_STRING, &err, errorstring) != 2)
{
syslog(LOG_ERR, _("Got bad ERROR from %s (%s)"),
cl->name, cl->hostname);
if(debug_lvl >= DEBUG_ERROR)
{
syslog(LOG_NOTICE, _("Error message from %s (%s): %s: %s"),
- cl->name, cl->hostname, strerror(errno), errorstring);
+ cl->name, cl->hostname, strerror(err), errorstring);
}
- free(errorstring);
- cl->status.termreq = 1;
- terminate_connection(cl);
+ terminate_connection(cl, cl->status.meta);
cp
return 0;
}
-int send_termreq(conn_list_t *cl)
+int send_termreq(connection_t *cl)
{
cp
return send_request(cl, "%d", TERMREQ);
}
-int termreq_h(conn_list_t *cl)
+int termreq_h(connection_t *cl)
{
cp
- cl->status.termreq = 1;
- terminate_connection(cl);
+ terminate_connection(cl, cl->status.meta);
cp
return 0;
}
-/* Keepalive routines - FIXME: needs a closer look */
-
-int send_ping(conn_list_t *cl)
+int send_ping(connection_t *cl)
{
+ char salt[SALTLEN*2+1];
+cp
cl->status.pinged = 1;
+ cl->last_ping_time = time(NULL);
+ RAND_pseudo_bytes(salt, SALTLEN);
+ bin2hex(salt, salt, SALTLEN);
+ salt[SALTLEN*2] = '\0';
cp
- return send_request(cl, "%d", PING);
+ return send_request(cl, "%d %s", PING, salt);
}
-int ping_h(conn_list_t *cl)
+int ping_h(connection_t *cl)
{
cp
return send_pong(cl);
}
-int send_pong(conn_list_t *cl)
+int send_pong(connection_t *cl)
{
+ char salt[SALTLEN*2+1];
+cp
+ RAND_pseudo_bytes(salt, SALTLEN);
+ bin2hex(salt, salt, SALTLEN);
+ salt[SALTLEN*2] = '\0';
cp
- return send_request(cl, "%d", PONG);
+ return send_request(cl, "%d %s", PONG, salt);
}
-int pong_h(conn_list_t *cl)
+int pong_h(connection_t *cl)
{
cp
- cl->status.got_pong = 1;
+ cl->status.pinged = 0;
cp
return 0;
}
/* Key exchange */
-int send_key_changed(conn_list_t *from, conn_list_t *cl)
+int send_key_changed(connection_t *from, connection_t *cl)
{
- conn_list_t *p;
+ connection_t *p;
+ avl_node_t *node;
cp
- for(p = conn_list; p != NULL; p = p->next)
+ /* Only send this message if some other daemon requested our key previously.
+ This reduces unnecessary key_changed broadcasts.
+ */
+
+ if(from==myself && !mykeyused)
+ return 0;
+
+ for(node = connection_tree->head; node; node = node->next)
{
- if(p!=cl && p->status.meta && p->status.active)
- send_request(p, "%d %s", KEY_CHANGED,
- from->name);
+ p = (connection_t *)node->data;
+ if(p != cl && p->status.active)
+ send_request(p, "%d %s", KEY_CHANGED, from->name);
}
cp
return 0;
}
-int key_changed_h(conn_list_t *cl)
+int key_changed_h(connection_t *cl)
{
- char *from_id;
- conn_list_t *from;
+ char from_id[MAX_STRING_SIZE];
+ connection_t *from;
cp
- if(sscanf(cl->buffer, "%*d %as", &from_id) != 1)
+ if(sscanf(cl->buffer, "%*d "MAX_STRING, from_id) != 1)
{
syslog(LOG_ERR, _("Got bad KEY_CHANGED from %s (%s)"),
cl->name, cl->hostname);
{
syslog(LOG_ERR, _("Got KEY_CHANGED from %s (%s) origin %s which does not exist in our connection list"),
cl->name, cl->hostname, from_id);
- free(from_id);
return -1;
}
- free(from_id);
-
from->status.validkey = 0;
from->status.waitingforkey = 0;
return 0;
}
-int send_req_key(conn_list_t *from, conn_list_t *to)
+int send_req_key(connection_t *from, connection_t *to)
{
cp
return send_request(to->nexthop, "%d %s %s", REQ_KEY,
from->name, to->name);
}
-int req_key_h(conn_list_t *cl)
+int req_key_h(connection_t *cl)
{
- char *from_id, *to_id;
- conn_list_t *from, *to;
+ char from_id[MAX_STRING_SIZE];
+ char to_id[MAX_STRING_SIZE];
+ connection_t *from, *to;
+ char pktkey[129];
cp
- if(sscanf(cl->buffer, "%*d %as %as", &from_id, &to_id) != 2)
+ if(sscanf(cl->buffer, "%*d "MAX_STRING" "MAX_STRING, from_id, to_id) != 2)
{
syslog(LOG_ERR, _("Got bad REQ_KEY from %s (%s)"),
cl->name, cl->hostname);
{
syslog(LOG_ERR, _("Got REQ_KEY from %s (%s) origin %s which does not exist in our connection list"),
cl->name, cl->hostname, from_id);
- free(from_id); free(to_id);
return -1;
}
/* Check if this key request is for us */
- if(!strcmp(to_id, myself->name))
+ if(!strcmp(to_id, myself->name)) /* Yes, send our own key back */
{
- send_ans_key(myself, from, myself->cipher_pktkey);
+ bin2hex(myself->cipher_pktkey, pktkey, myself->cipher_pktkeylength);
+ pktkey[myself->cipher_pktkeylength*2] = '\0';
+ send_ans_key(myself, from, pktkey);
+ mykeyused = 1;
}
else
{
{
syslog(LOG_ERR, _("Got REQ_KEY from %s (%s) destination %s which does not exist in our connection list"),
cl->name, cl->hostname, to_id);
- free(from_id); free(to_id);
return -1;
}
- send_req_key(from, to);
+
+ if(to->status.validkey) /* Proxy keys */
+ {
+ bin2hex(to->cipher_pktkey, pktkey, to->cipher_pktkeylength);
+ pktkey[to->cipher_pktkeylength*2] = '\0';
+ send_ans_key(to, from, pktkey);
+ }
+ else
+ send_req_key(from, to);
}
- free(from_id); free(to_id);
cp
return 0;
}
-int send_ans_key(conn_list_t *from, conn_list_t *to, char *pktkey)
+int send_ans_key(connection_t *from, connection_t *to, char *pktkey)
{
cp
return send_request(to->nexthop, "%d %s %s %s", ANS_KEY,
from->name, to->name, pktkey);
}
-int ans_key_h(conn_list_t *cl)
+int ans_key_h(connection_t *cl)
{
- char *from_id, *to_id, *pktkey;
+ char from_id[MAX_STRING_SIZE];
+ char to_id[MAX_STRING_SIZE];
+ char pktkey[MAX_STRING_SIZE];
int keylength;
- conn_list_t *from, *to;
+ connection_t *from, *to;
cp
- if(sscanf(cl->buffer, "%*d %as %as %as", &from_id, &to_id, &pktkey) != 3)
+ if(sscanf(cl->buffer, "%*d "MAX_STRING" "MAX_STRING" "MAX_STRING, from_id, to_id, pktkey) != 3)
{
syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s)"),
cl->name, cl->hostname);
{
syslog(LOG_ERR, _("Got ANS_KEY from %s (%s) origin %s which does not exist in our connection list"),
cl->name, cl->hostname, from_id);
- free(from_id); free(to_id); free(pktkey);
return -1;
}
- /* Check if this key request is for us */
+ /* Check correctness of packet key */
+
+ keylength = strlen(pktkey);
- if(!strcmp(to_id, myself->name))
+ if(keylength != from->cipher_pktkeylength*2)
{
- /* It is for us, convert it to binary and set the key with it. */
+ syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s) origin %s: invalid key length"),
+ cl->name, cl->hostname, from->name);
+ return -1;
+ }
- keylength = strlen(pktkey);
+ /* Forward it if necessary */
- if((keylength%2) || (keylength <= 0))
- {
- syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s) origin %s: invalid key"),
- cl->name, cl->hostname, from->name);
- free(from_id); free(to_id); free(pktkey);
- return -1;
- }
- keylength /= 2;
- hex2bin(pktkey, pktkey, keylength);
- BF_set_key(cl->cipher_pktkey, keylength, pktkey);
- }
- else
+ if(strcmp(to_id, myself->name))
{
if(!(to = lookup_id(to_id)))
{
syslog(LOG_ERR, _("Got ANS_KEY from %s (%s) destination %s which does not exist in our connection list"),
cl->name, cl->hostname, to_id);
- free(from_id); free(to_id); free(pktkey);
return -1;
}
send_ans_key(from, to, pktkey);
}
- free(from_id); free(to_id); free(pktkey);
+ /* Update our copy of the origin's packet key */
+
+ if(from->cipher_pktkey)
+ free(from->cipher_pktkey);
+
+ from->cipher_pktkey = xstrdup(pktkey);
+ keylength /= 2;
+ hex2bin(from->cipher_pktkey, from->cipher_pktkey, keylength);
+ from->cipher_pktkey[keylength] = '\0';
+
+ from->status.validkey = 1;
+ from->status.waitingforkey = 0;
+
+ flush_queue(from);
+cp
+ return 0;
+}
+
+int send_tcppacket(connection_t *cl, vpn_packet_t *packet)
+{
+ int x;
+cp
+ /* Evil hack. */
+
+ x = send_request(cl->nexthop, "%d %hd", PACKET, packet->len);
+
+ if(x)
+ return x;
+cp
+ return send_meta(cl, packet->data, packet->len);
+}
+
+int tcppacket_h(connection_t *cl)
+{
+ short int len;
+cp
+ if(sscanf(cl->buffer, "%*d %hd", &len) != 1)
+ {
+ syslog(LOG_ERR, _("Got bad PACKET from %s (%s)"), cl->name, cl->hostname);
+ return -1;
+ }
+
+ /* Set reqlen to len, this will tell receive_meta() that a tcppacket is coming. */
+
+ cl->tcplen = len;
cp
return 0;
}
/* Jumptable for the request handlers */
-int (*request_handlers[])(conn_list_t*) = {
- id_h, challenge_h, chal_reply_h, ack_h,
+int (*request_handlers[])(connection_t*) = {
+ id_h, metakey_h, challenge_h, chal_reply_h,
status_h, error_h, termreq_h,
ping_h, pong_h,
add_host_h, del_host_h,
add_subnet_h, del_subnet_h,
key_changed_h, req_key_h, ans_key_h,
+ tcppacket_h,
};
/* Request names */
char (*request_name[]) = {
- "ID", "CHALLENGE", "CHAL_REPLY", "ACK",
+ "ID", "METAKEY", "CHALLENGE", "CHAL_REPLY",
"STATUS", "ERROR", "TERMREQ",
"PING", "PONG",
"ADD_HOST", "DEL_HOST",
"ADD_SUBNET", "DEL_SUBNET",
"KEY_CHANGED", "REQ_KEY", "ANS_KEY",
+ "PACKET",
};
/* Status strings */