X-Git-Url: https://tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fprotocol.c;h=9b30a8a6366199dce506e6aead9ab40eced3251f;hp=b68b83a94f2f8df33104b5862420204cd1452bf6;hb=17bc5220c332fdd083fd47fc600010f85171adc7;hpb=6b9ec9ed1e818d5e50dda4418ffb4d02c898bcba

diff --git a/src/protocol.c b/src/protocol.c
index b68b83a9..9b30a8a6 100644
--- a/src/protocol.c
+++ b/src/protocol.c
@@ -1,7 +1,7 @@
 /*
-    protocol.c -- handle the meta-protocol
-    Copyright (C) 1999,2000 Ivo Timmermans <itimmermans@bigfoot.com>,
-                       2000 Guus Sliepen <guus@sliepen.warande.net>
+    protocol.c -- handle the meta-protocol, basic functions
+    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
@@ -17,7 +17,7 @@
     along with this program; if not, write to the Free Software
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 
-    $Id: protocol.c,v 1.28.4.26 2000/09/10 16:15:35 guus Exp $
+    $Id: protocol.c,v 1.28.4.123 2002/02/27 22:37:54 guus Exp $
 */
 
 #include "config.h"
@@ -27,1244 +27,144 @@
 #include <stdlib.h>
 #include <string.h>
 #include <syslog.h>
-#include <sys/socket.h>
-#include <unistd.h>
 #include <stdio.h>
+#include <stdarg.h>
+#include <errno.h>
 
 #include <utils.h>
-#include <xalloc.h>
 
-#include <netinet/in.h>
-
-#include "conf.h"
-#include "encr.h"
-#include "net.h"
-#include "netutl.h"
-#include "protocol.h"
-
-#include "system.h"
-
-/* Generic outgoing request routine - takes care of logging and error detection as well */
-
-int send_request(conn_list_t *cl, const char *format, int request, /*args*/ ...)
-{
-  va_list args;
-  char *buffer = NULL;
-cp
-  if(debug_lvl >= DEBUG_PROTOCOL)
-    syslog(LOG_DEBUG, _("Sending %s to %s (%s)"), requestname[request], cl->id, cl->hostname);
-
-  va_start(args, format);
-  len = vasprintf(&buffer, format, args);
-  va_end(args);
-
-  if(len < 0 || !buffer)
-    {
-      syslog(LOG_ERR, _("Error during vasprintf(): %m"));
-      return -1;
-    }
-
-  if(debug_lvl >= DEBUG_META)
-    syslog(LOG_DEBUG, _("Sending meta data to %s (%s): %s"), cl->id, cl->hostname, buffer);
-
-  if(cl->status.encryptout)
-    {
-      /* FIXME: Do encryption */
-    }
-
-  if((write(cl->meta_socket, buffer, buflen)) < 0)
-    {
-      syslog(LOG_ERR, _("Sending meta data failed:  %m"));
-      return -1;
-    }
-cp  
-}
-
-/* Connection protocol:
-
-   Client               Server
-   send_id(*)
-                        send_challenge
-   send_chal_reply(*)                   
-                        send_id
-   send_challenge
-                        send_chal_reply
-   send_ack
-			send_ack
-
-   (*) Unencrypted.
-*/      
-
-int send_id(conn_list_t *cl)
-{
-cp
-  return send_request(cl, "%d %s %d-%d %s", ID, myself->id, myself->min_version, myself->max_version, opt2str(myself->options));
-}
-
-int id_h(conn_list_t *cl)
-{
-  conn_list_t *old;
-  char *options;
-cp
-  if(sscanf(cl->buffer, "%*d %as %d-%d %as", &cl->id, &cl->min_version, &cl->max_version, &options) != 4)
-    {
-       syslog(LOG_ERR, _("Got bad ID from %s"), cl->hostname);
-       return -1;
-    }
-    
-  /* Check if version ranges overlap */
-  
-  if((cl->min_version > myself->max_version) || (cl->max_version < myself_min_version) || (cl->min_version > cl->max_version))
-    {
-      syslog(LOG_ERR, _("Peer %s uses incompatible version (%d-%d)"), cl->hostname, cl->min_version, cl->max_version);
-      return -1;
-    }
-
-  /* Check if option string is valid */
-  
-  if(str2opt(options) == -1)
-    {
-      syslog(LOG_ERR, _("Peer %s uses invalid option string"), cl->hostname);
-      return -1;
-    }
-    
-  /* Check if identity is a valid name */
-  
-  if(!check_id(cl->id))
-    {
-      syslog(LOG_ERR, _("Peer %s uses invalid identity name"), cl->hostname);
-      return -1;
-    }
-    
-  /* Load information about peer */
-  
-  if(!read_id(cl))
-    {
-      syslog(LOG_ERR, _("Peer %s had unknown identity (%s)"), cl->hostname, cl->id);
-      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.
-   */
-
-  if(cl->status.outgoing)
-    {
-      if((old=lookup_id(cl->id)))
-        {
-          if(debug_lvl > DEBUG_CONNECTIONS)
-            syslog(LOG_NOTICE, _("Uplink %s (%s) is already in our connection list"), cl->id, cl->hostname);
-          cl->status.outgoing = 0;
-          old->status.outgoing = 1;
-          terminate_connection(cl);
-          return 0;
-        }
-    }
-
-  /* Since we know the identity now, we can encrypt the meta channel */
-  
-  cl->status.encryptout = 1;
-
-  /* Send a challenge to verify the identity */
-
-  cl->allow_request = CHAL_REPLY;
-cp
-  return send_challenge(cl);
-}
-
-int send_challenge(conn_list_t *cl)
-{
-  char *buffer;
-  int keylength;
-  int x;
-cp
-  if(cl->chal_hash)
-    free(cl->chal_hash);
-  
-  /* Allocate buffers for the challenge and the hash */
-  
-  cl->chal_hash = xmalloc(SHA_DIGEST_LEN);
-  keylength = BN_num_bytes(cl->metakey.n);
-  buffer = xmalloc(keylength*2);
-
-  /* Copy random data and the public key to the buffer */
-  
-  RAND_bytes(buffer, keylength);
-  BN_bn2bin(cl->metakey.n, buffer+keylength);
-
-  /* Calculate the hash from that */
-
-  SHA1(buffer, keylength*2, cl->chal_hash);
-
-  /* Convert the random data to a hexadecimal formatted string */
-
-  bin2hex(buffer,buffer,keylength);
-  buffer[keylength*2] = '\0';
-
-  /* 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)
-{
-  char *challenge;
-cp
-  if(sscanf(cl->buffer, "%*d %as", &cl->id, &challenge) != 1)
-    {
-       syslog(LOG_ERR, _("Got bad CHALLENGE from %s (%s)"), cl->id, cl->hostname);
-       return -1;
-    }
-
-  /* Rest is done by send_chal_reply() */
-  
-  x = send_chal_reply(cl, challenge);
-  free(challenge);
-cp
-  return x;
-}
-
-int send_chal_reply(conn_list_t *cl, char *challenge)
-{
-  char *buffer;
-  int keylength;
-  char *hash;
-  int x;
-cp
-  keylength = BN_num_bytes(myself->meyakey.n);
-
-  /* Check if the length of the challenge is all right */
-
-  if(strlen(challenge) != keylength*2)
-    {
-      syslog(LOG_ERROR, _("Intruder: wrong challenge length from %s (%s)"), cl->id, cl->hostname);
-      return -1;
-    }
-
-  /* Allocate buffers for the challenge and the hash */
-  
-  buffer = xmalloc(keylength*2);
-  hash = xmalloc(SHA_DIGEST_LEN*2+1);
-
-  /* Copy the incoming random data and our public key to the buffer */
-
-  hex2bin(challenge, buffer, keylength); 
-  BN_bn2bin(myself->metakey.n, buffer+keylength);
-
-  /* Calculate the hash from that */
-  
-  SHA1(buffer, keylength*2, hash);
-  free(buffer);
-
-  /* Convert the hash to a hexadecimal formatted string */
-
-  bin2hex(hash,hash,SHA_DIGEST_LEN);
-  hash[SHA_DIGEST_LEN*2] = '\0';
-
-  /* Send the reply */
-
-  if(cl->status.outgoing)
-    cl->allow_resuest = ID;
-  else
-    cl->allow_request = ACK;
-
-  x = send_request(cl, "%d %s", CHAL_REPLY, hash);
-  free(hash);
-cp
-  return x;
-} 
-
-int chal_reply_h(conn_list_t *cl)
-{
-  char *hash;
-cp
-  if(sscanf(cl->buffer, "%*d %as", &cl->id, &hash) != 2)
-    {
-       syslog(LOG_ERR, _("Got bad CHAL_REPLY from %s (%s)"), cl->id, cl->hostname);
-       return -1;
-    }
-
-  /* Check if the length of the hash is all right */
-  
-  if(strlen(hash) != SHA_DIGEST_LEN*2)
-    {
-      syslog(LOG_ERROR, _("Intruder: wrong challenge reply length from %s (%s)"), cl->id, cl->hostname);
-      return -1;
-    }
-    
-  /* Convert the hash to binary format */
-  
-  hex2bin(hash, hash, SHA_DIGEST_LEN);
-  
-  /* Verify the incoming hash with the calculated hash */
-  
-  if{!memcmp(hash, cl->chal_hash, SHA_DIGEST_LEN)}
-    {
-      syslog(LOG_ERROR, _("Intruder: wrong challenge reply from %s (%s)"), cl->id, cl->hostname);
-      return -1;
-    }
-
-  /* Identity has now been positively verified.
-     If we are accepting this new connection, then send our identity,
-     if we are making this connecting, acknowledge.
-   */
-   
-  free(hash);
-  free(cl->chal_hash);
-
-cp
-  if(cl->status.outgoing)
-    {
-      cl->allow_request = ACK;
-      return send_ack(cl);
-    }
-  else
-    {
-      cl->allow_request = CHALLENGE;
-      return send_id(cl);
-    }
-}
-
-int send_ack(conn_list_t *cl)
-{
-cp
-  return send_request(cl, "%d", ACK);
-}
-
-int ack_h(conn_list_t *cl)
-{
-  conn_list_t old;
-cp
-  /* Okay, before we active the connection, we check if there is another entry
-     in the connection list with the same vpn_ip. If so, it presumably is an
-     old connection that has timed out but we don't know it yet.
-   */
-
-  while((old = lookup_id(cl->id))) 
-    {
-      if(debug_lvl > DEBUG_CONNECTIONS)
-        syslog(LOG_NOTICE, _("Removing old entry for %s at %s in favour of new connection from %s"),
-        cl->id, old->hostname, cl->hostname);
-      old->status.active = 0;
-      terminate_connection(old);
-    }
-
-  /* Activate this connection */
-
-  cl->allow_request = ALL;
-  cl->status.active = 1;
-
-  if(debug_lvl > DEBUG_CONNECTIONS)
-    syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), cl->id, cl->hostname);
-
-  /* Exchange information about other tinc daemons */
-
-  notify_others(cl, NULL, send_add_host);
-  notify_one(cl);
-
-  upstreamindex = 0;
-
-cp
-  if(cl->status.outgoing)
-    return 0;
-  else
-    return send_ack(cl);
-}
-
-/* Address and subnet information exchange */
-
-int send_add_subnet(conn_list_t *cl, conn_list_t *other, subnet_t *subnet)
-{
-cp
-  return send_meta(cl, "%d %s %d %s", ADD_SUBNET, other->id, subnet->type, net2str(subnet));
-}
-
-int add_subnet_h(conn_list_t *cl)
-{
-}
-
-int send_del_subnet(conn_list_t *cl, conn_list_t *other, subnet_t *subnet)
-{
-cp
-  return send_meta(cl, "%d %s %d %s", DEL_SUBNET, other->id, subnet->type, net2str(subnet));
-}
-
-int del_subnet_h(conn_list_t *cl)
-{
-}
-
-/* New and closed connections notification */
-
-int send_add_host(conn_list_t *cl, conn_list_t *other)
-{
-cp
-  return send_meta(cl, "%d %lx:%d", ADD_HOST, other->id, other->address, other->port);
-}
-
-int add_host_h(conn_list_t *cl)
-{
-}
-
-int send_del_host(conn_list_t *cl, conn_list_t *other)
-{
-cp
-  return send_meta(cl, "%d %lx:%d", DEL_HOST, other->id, other->address, other->port);
-}
-
-int del_host_h(conn_list_t *cl)
-{
-}
-
-/* Status and error notification routines */
-
-int send_status(conn_list_t *cl, int statusno, char *statusstring)
-{
-cp
-  if(!statusstring)
-    statusstring = status_text[statusno];
-cp
-  return send_request(cl, "%d %d %s", STATUS, statusno, statusstring);
-}
-
-int status_h(conn_list_t *cl)
-{
-  int statusno;
-  char *statusstring;
-cp
-  if(sscanf(cl->buffer, "%*d %d %as", &statusno, &statusstring) != 2)
-    {
-       syslog(LOG_ERR, _("Got bad STATUS from %s (%s)"), cl->id, cl->hostname);
-       return -1;
-    }
-
-  if(debug_lvl > DEBUG_STATUS)
-    {
-      syslog(LOG_NOTICE, _("Status message from %s (%s): %s: %s"), cl->id, cl->hostname, status_text[statusno], statusstring);
-    }
-
-cp
-  free(statusstring);
-  return 0;
-}
-
-int send_error(conn_list_t *cl, int errno, char *errstring)
-{
-cp
-  if(!errorstring)
-    errorstring = error_text[errno];
-  return send_request(cl, "%d %d %s", ERROR, errno, errstring);
-}
-
-int error_h(conn_list_t *cl)
-{
-  int errno;
-  char *errorstring;
-cp
-  if(sscanf(cl->buffer, "%*d %d %as", &errno, &errorstring) != 2)
-    {
-       syslog(LOG_ERR, _("Got bad error from %s (%s)"), cl->id, cl->hostname);
-       return -1;
-    }
-
-  if(debug_lvl > DEBUG_error)
-    {
-      syslog(LOG_NOTICE, _("Error message from %s (%s): %s: %s"), cl->id, cl->hostname, error_text[errno], errorstring);
-    }
-
-cp
-  free(errorstring);
-  return 0;
-}
-
-int send_termreq(conn_list_t *cl)
-{
-}
-
-int termreq_h(conn_list_t *cl)
-{
-}
-
-/* Keepalive routines */
-
-int send_ping(conn_list_t *cl)
-{
-cp
-  return send_meta(cl, "%d", PING);
-}
-
-int ping_h(conn_list_t *cl)
-{
-}
-
-int send_pong(conn_list_t *cl)
-{
-cp
-  return send_meta(cl, "%d", PONG);
-}
-
-int pong_h(conn_list_t *cl)
-{
-}
-
-/* Key exchange */
-
-int send_req_key(conn_list_t *cl, conn_list_t *source)
-{
-cp
-  return send_meta(cl, "%d %s", REQ_KEY, source->id);
-}
-
-int req_key_h(conn_list_t *cl)
-{
-}
-
-int send_key(conn_list_t *cl)
-{
-}
-
-int key_h(conn_list_t *cl)
-{
-}
-
-
-
-
-/* Old routines */
-
-
-int send_termreq(conn_list_t *cl)
-{
-cp
-  if(debug_lvl > 1)
-    syslog(LOG_DEBUG, _("Sending TERMREQ to %s (%s)"),
-	   cl->vpn_hostname, cl->real_hostname);
-
-  buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx\n", TERMREQ, myself->vpn_ip);
-
-  if(write(cl->meta_socket, buffer, buflen) < 0)
-    {
-      if(debug_lvl > 1)
-	syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__);
-      return -1;
-    }
-cp
-  return 0;
-}
-
-int send_timeout(conn_list_t *cl)
-{
-cp
-  if(debug_lvl > 1)
-    syslog(LOG_DEBUG, _("Sending TIMEOUT to %s (%s)"),
-	   cl->vpn_hostname, cl->real_hostname);
-
-  buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx\n", PINGTIMEOUT, myself->vpn_ip);
-
-  if((write(cl->meta_socket, buffer, buflen)) < 0)
-    {
-      syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__);
-      return -1;
-    }
-cp
-  return 0;
-}
-
-int send_del_host(conn_list_t *cl, conn_list_t *new_host)
-{
-cp
-  if(debug_lvl > 1)
-    syslog(LOG_DEBUG, _("Sending DEL_HOST for %s (%s) to %s (%s)"),
-	   new_host->vpn_hostname, new_host->real_hostname, cl->vpn_hostname, cl->real_hostname);
-
-  buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx\n", DEL_HOST, new_host->vpn_ip);
-
-  if((write(cl->meta_socket, buffer, buflen)) < 0)
-    {
-      syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__);
-      return -1;
-    }
-cp
-  return 0;
-}
-
-int send_tcppacket(conn_list_t *cl, void *data, int len)
-{
-cp
-  if(debug_lvl > 3)
-    syslog(LOG_DEBUG, _("Sending PACKET to %s (%s)"),
-	   cl->vpn_hostname, cl->real_hostname);
-
-  buflen = snprintf(buffer, MAXBUFSIZE, "%d %d\n", PACKET, len);
-
-  if((write(cl->meta_socket, buffer, buflen)) < 0)
-    {
-      syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__);
-      return -1;
-    }
-    
-  if((write(cl->meta_socket, data, len)) < 0)
-    {
-      syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__);
-      return -1;
-    }
-cp
-  return 0;
-}
-
-int send_ping(conn_list_t *cl)
-{
-cp
-  if(debug_lvl > 1)
-    syslog(LOG_DEBUG, _("Sending PING to %s (%s)"),
-	   cl->vpn_hostname, cl->real_hostname);
-
-  buflen = snprintf(buffer, MAXBUFSIZE, "%d\n", PING);
-
-  if((write(cl->meta_socket, buffer, buflen)) < 0)
-    {
-      syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__);
-      return -1;
-    }
-cp
-  return 0;
-}
-
-int send_pong(conn_list_t *cl)
-{
-cp
-  if(debug_lvl > 1)
-    syslog(LOG_DEBUG, _("Sending PONG to %s (%s)"),
-	   cl->vpn_hostname, cl->real_hostname);
-
-  buflen = snprintf(buffer, MAXBUFSIZE, "%d\n", PONG);
-
-  if((write(cl->meta_socket, buffer, buflen)) < 0)
-    {
-      syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__);
-      return -1;
-    }
-cp
-  return 0;
-}
-
-int send_add_host(conn_list_t *cl, conn_list_t *new_host)
-{
-  ip_t real_ip;
-  int flags;
-  char *hostname;
-cp
-  real_ip = new_host->real_ip;
-  hostname = new_host->real_hostname;
-  flags = new_host->flags;
-  
-  /* If we need to propagate information about a new host that wants us to export
-   * it's indirectdata flag, we set the INDIRECTDATA flag and unset the EXPORT...
-   * flag, and set it's real_ip to our vpn_ip, so that net.c send_packet() will
-   * work correctly.
-   */
-     
-  if(flags & EXPORTINDIRECTDATA)
-    {
-      flags &= ~EXPORTINDIRECTDATA;
-      flags |= INDIRECTDATA;
-      real_ip = myself->vpn_ip;
-      hostname = myself->real_hostname;
-    }
-
-  if(debug_lvl > 1)
-    syslog(LOG_DEBUG, _("Sending ADD_HOST for %s (%s) to %s (%s)"),
-	   new_host->vpn_hostname, hostname, cl->vpn_hostname, cl->real_hostname);
-
-  buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx %lx/%lx:%x %d\n", ADD_HOST, real_ip, new_host->vpn_ip, new_host->vpn_mask, new_host->port, flags);
-
-  if((write(cl->meta_socket, buffer, buflen)) < 0)
-    {
-      syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__);
-      return -1;
-    }
-cp
-  return 0;
-}
-
-int send_key_changed(conn_list_t *cl, conn_list_t *src)
-{
-cp
-  if(debug_lvl > 1)
-    syslog(LOG_DEBUG, _("Sending KEY_CHANGED origin %s to %s (%s)"),
-	   src->vpn_hostname, cl->vpn_hostname, cl->real_hostname);
-
-  buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx\n", KEY_CHANGED, src->vpn_ip);
-
-  if((write(cl->meta_socket, buffer, buflen)) < 0)
-    {
-      syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__);
-      return -1;
-    }
-cp
-  return 0;
-}
-
-void send_key_changed_all(void)
-{
-  conn_list_t *p;
-cp
-  for(p = conn_list; p != NULL; p = p->next)
-    if(p->status.meta && p->status.active)
-      send_key_changed(p, myself);
-cp
-}
-
-
-int send_key_request(ip_t to)
-{
-  conn_list_t *fw;
-cp
-  fw = lookup_conn(to);
-  if(!fw)
-    {
-      syslog(LOG_ERR, _("Attempting to send REQ_KEY to %d.%d.%d.%d, which does not exist?"),
-	     IP_ADDR_V(to));
-      return -1;
-    }
-
-  if(debug_lvl > 1)
-    syslog(LOG_DEBUG, _("Sending REQ_KEY to %s (%s)"),
-	   fw->nexthop->vpn_hostname, fw->nexthop->real_hostname);
-
-  buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx %lx\n", REQ_KEY, to, myself->vpn_ip);
-
-  if((write(fw->nexthop->meta_socket, buffer, buflen)) < 0)
-    {
-      syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__);
-      return -1;
-    }
-  fw->status.waitingforkey = 1;
-cp
-  return 0;
-}
-
-int send_key_answer(conn_list_t *cl, ip_t to)
-{
-  conn_list_t *fw;
-cp
-
-  fw = lookup_conn(to);
-  
-  if(!fw)
-    {
-      syslog(LOG_ERR, _("Attempting to send ANS_KEY to %d.%d.%d.%d, which does not exist?"),
-	     IP_ADDR_V(to));
-      return -1;
-    }
-
- if(debug_lvl > 1)
-    syslog(LOG_DEBUG, _("Sending ANS_KEY to %s (%s)"),
-	   fw->nexthop->vpn_hostname, fw->nexthop->real_hostname);
-
-  buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx %lx %d %s\n", ANS_KEY, to, myself->vpn_ip, my_key_expiry, my_public_key_base36);
-
-  if((write(fw->nexthop->meta_socket, buffer, buflen)) < 0)
-    {
-      syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__);
-      return -1;
-    }
-cp
-  return 0;
-}
+#include "conf.h"
+#include "protocol.h"
+#include "meta.h"
+#include "connection.h"
 
-/*
-  notify all my direct connections of a new host
-  that was added to the vpn, with the exception
-  of the source of the announcement.
-*/
-int notify_others(conn_list_t *new, conn_list_t *source,
-		  int (*function)(conn_list_t*, conn_list_t*))
-{
-  conn_list_t *p;
-cp
-  for(p = conn_list; p != NULL; p = p->next)
-    if(p != new && p != source && p->status.meta && p->status.active)
-      function(p, new);
-cp
-  return 0;
-}
+#include "system.h"
 
-/*
-  notify one connection of everything
-  i have connected
-*/
-int notify_one(conn_list_t *new)
+int check_id(char *id)
 {
-  conn_list_t *p;
-cp
-  for(p = conn_list; p != NULL; p = p->next)
-    if(p != new && p->status.active)
-      send_add_host(new, p);
-cp
-  return 0;
-}
-
-/*
-  The incoming request handlers
-*/
-
+  int i;
 
-int termreq_h(conn_list_t *cl)
-{
-cp
-  if(!cl->status.active)
-    {
-      syslog(LOG_ERR, _("Got unauthorized TERMREQ from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
+  for (i = 0; i < strlen(id); i++)
+    if(!isalnum(id[i]) && id[i] != '_')
       return -1;
-    }
-    
-  if(debug_lvl > 1)
-   syslog(LOG_DEBUG, _("Got TERMREQ from %s (%s)"),
-             cl->vpn_hostname, cl->real_hostname);
   
-  cl->status.termreq = 1;
-
-  terminate_connection(cl);
-cp
-  return 0;
-}
-
-int timeout_h(conn_list_t *cl)
-{
-cp
-  if(!cl->status.active)
-    {
-      syslog(LOG_ERR, _("Got unauthorized TIMEOUT from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
-      return -1;
-    }
-
-  if(debug_lvl > 1)
-    syslog(LOG_DEBUG, _("Got TIMEOUT from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
-
-  cl->status.termreq = 1;
-  terminate_connection(cl);
-cp
   return 0;
 }
 
-int del_host_h(conn_list_t *cl)
-{
-  ip_t vpn_ip;
-  conn_list_t *fw;
-cp
-  if(!cl->status.active)
-    {
-      syslog(LOG_ERR, _("Got unauthorized DEL_HOST from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
-      return -1;
-    }
-
-  if(sscanf(cl->buffer, "%*d %lx", &vpn_ip) != 1)
-    {
-       syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
-       return -1;
-    }  
-
-  if(!(fw = lookup_conn(vpn_ip)))
-    {
-      syslog(LOG_ERR, _("Got DEL_HOST for %d.%d.%d.%d from %s (%s) which does not exist?"),
-	     IP_ADDR_V(vpn_ip), cl->vpn_hostname, cl->real_hostname);
-      return 0;
-    }
-
-  /* Connections lists are really messed up if this happens */
-  if(vpn_ip == myself->vpn_ip)
-    {
-      syslog(LOG_ERR, _("Warning: got DEL_HOST from %s (%s) for ourself, restarting"),
-               cl->vpn_hostname, cl->real_hostname);
-      sighup = 1;
-      return 0;
-    }
-
-  if(debug_lvl > 1)
-    syslog(LOG_DEBUG, _("Got DEL_HOST for %s (%s) from %s (%s)"),
-           fw->vpn_hostname, fw->real_hostname, cl->vpn_hostname, cl->real_hostname);
-
-  notify_others(fw, cl, send_del_host);
-
-  fw->status.termreq = 1;
-  fw->status.active = 0;
-
-  terminate_connection(fw);
-cp
-  return 0;
-}
+/* Generic request routines - takes care of logging and error
+   detection as well */
 
-int tcppacket_h(conn_list_t *cl)
+int send_request(connection_t *c, const char *format, ...)
 {
-  int len;
-cp
-  if(!cl->status.active)
-    {
-      syslog(LOG_ERR, _("Got unauthorized PACKET from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
-      return -1;
-    }
-
-  if(sscanf(cl->buffer, "%*d %d", &len) != 1)
-    {
-       syslog(LOG_ERR, _("Got bad PACKET from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
-       return -1;
-    }  
-
-  if(len > MTU)
-    {
-       syslog(LOG_ERR, _("Got too big PACKET from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
-       return -1;
-    }  
-
-  if(debug_lvl > 3)
-    syslog(LOG_DEBUG, _("Got PACKET length %d from %s (%s)"), len,
-              cl->vpn_hostname, cl->real_hostname);
+  va_list args;
+  char buffer[MAXBUFSIZE];
+  int len, request;
 
-  cl->tcppacket=len;
 cp
-  return 0;
-}
+  /* 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);
+  va_end(args);
 
-int ping_h(conn_list_t *cl)
-{
-cp
-  if(!cl->status.active)
+  if(len < 0 || len > MAXBUFSIZE-1)
     {
-      syslog(LOG_ERR, _("Got unauthorized PING from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
+      syslog(LOG_ERR, _("Output buffer overflow while sending request to %s (%s)"), request_name[request], c->name, c->hostname);
       return -1;
     }
 
-  if(debug_lvl > 1)
-    syslog(LOG_DEBUG, _("Got PING from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
-
-  cl->status.pinged = 0;
-  cl->status.got_pong = 1;
-
-  send_pong(cl);
-cp
-  return 0;
-}
-
-int pong_h(conn_list_t *cl)
-{
-cp
-  if(!cl->status.active)
+  if(debug_lvl >= DEBUG_PROTOCOL)
     {
-      syslog(LOG_ERR, _("Got unauthorized PONG from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
-      return -1;
+      sscanf(buffer, "%d", &request);
+      if(debug_lvl >= DEBUG_META)
+        syslog(LOG_DEBUG, _("Sending %s to %s (%s): %s"), request_name[request], c->name, c->hostname, buffer);
+      else
+        syslog(LOG_DEBUG, _("Sending %s to %s (%s)"), request_name[request], c->name, c->hostname);
     }
 
-  if(debug_lvl > 1)
-    syslog(LOG_DEBUG, _("Got PONG from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
-
-  cl->status.got_pong = 1;
+  buffer[len++] = '\n';
 cp
-  return 0;
+  return send_meta(c, buffer, len);
 }
 
-int add_host_h(conn_list_t *cl)
+int receive_request(connection_t *c)
 {
-  ip_t real_ip;
-  ip_t vpn_ip;
-  ip_t vpn_mask;
-  unsigned short port;
-  int flags;
-  conn_list_t *ncn, *old;
+  int request;
 cp
-  if(!cl->status.active)
+  if(sscanf(c->buffer, "%d", &request) == 1)
     {
-      syslog(LOG_ERR, _("Got unauthorized ADD_HOST from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
-      return -1;
-    }
-    
-  if(sscanf(cl->buffer, "%*d %lx %lx/%lx:%hx %d", &real_ip, &vpn_ip, &vpn_mask, &port, &flags) != 5)
-    {
-       syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
-       return -1;
-    }  
-
-  if((old = lookup_conn(vpn_ip)))
-    {
-      if((real_ip==old->real_ip) && (vpn_mask==old->vpn_mask) && (port==old->port))
+      if((request < 0) || (request >= LAST) || (request_handlers[request] == NULL))
         {
-          if(debug_lvl>1)
-            syslog(LOG_NOTICE, _("Got duplicate ADD_HOST for %s (%s) from %s (%s)"),
-                   old->vpn_hostname, old->real_hostname, cl->vpn_hostname, cl->real_hostname);
-          goto skip_add_host;  /* One goto a day keeps the deeply nested if constructions away. */
+          if(debug_lvl >= DEBUG_META)
+            syslog(LOG_DEBUG, _("Unknown request from %s (%s): %s"),
+	           c->name, c->hostname, c->buffer);
+          else
+            syslog(LOG_ERR, _("Unknown request from %s (%s)"),
+                   c->name, c->hostname);
+                   
+          return -1;
         }
       else
         {
-          if(debug_lvl>1)
-            syslog(LOG_NOTICE, _("Removing old entry for %s (%s)"),
-                   old->vpn_hostname, old->real_hostname);
-          old->status.active = 0;
-          terminate_connection(old);
+          if(debug_lvl >= DEBUG_PROTOCOL)
+            {
+              if(debug_lvl >= DEBUG_META)
+                syslog(LOG_DEBUG, _("Got %s from %s (%s): %s"),
+	               request_name[request], c->name, c->hostname, c->buffer);
+              else
+                syslog(LOG_DEBUG, _("Got %s from %s (%s)"),
+		       request_name[request], c->name, c->hostname);
+            }
+	}
+
+      if((c->allow_request != ALL) && (c->allow_request != request))
+        {
+          syslog(LOG_ERR, _("Unauthorized request from %s (%s)"), c->name, c->hostname);
+          return -1;
         }
-    }
-  
-  /* Connections lists are really messed up if this happens */
-  if(vpn_ip == myself->vpn_ip)
-    {
-      syslog(LOG_ERR, _("Warning: got ADD_HOST from %s (%s) for ourself, restarting"),
-               cl->vpn_hostname, cl->real_hostname);
-      sighup = 1;
-      return 0;
-    }
-    
-  ncn = new_conn_list();
-  ncn->real_ip = real_ip;
-  ncn->real_hostname = hostlookup(htonl(real_ip));
-  ncn->vpn_ip = vpn_ip;
-  ncn->vpn_mask = vpn_mask;
-  ncn->vpn_hostname = hostlookup(htonl(vpn_ip));
-  ncn->port = port;
-  ncn->flags = flags;
-  ncn->nexthop = cl;
-  ncn->next = conn_list;
-  conn_list = ncn;
-  ncn->status.active = 1;
-
-  if(debug_lvl > 1)
-    syslog(LOG_DEBUG, _("Got ADD_HOST for %s (%s) from %s (%s)"),
-           ncn->vpn_hostname, ncn->real_hostname, cl->vpn_hostname, cl->real_hostname);
-
-  notify_others(ncn, cl, send_add_host);
-
-skip_add_host:
-cp
-  return 0;
-}
-
-int req_key_h(conn_list_t *cl)
-{
-  ip_t to;
-  ip_t from;
-  conn_list_t *fw;
-cp
-  if(!cl->status.active)
-    {
-      syslog(LOG_ERR, _("Got unauthorized REQ_KEY from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
-      return -1;
-    }
-
-  if(sscanf(cl->buffer, "%*d %lx %lx", &to, &from) != 2)
-    {
-       syslog(LOG_ERR, _("Got bad REQ_KEY from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
-       return -1;
-    }  
-
-  if(debug_lvl > 1)
-    syslog(LOG_DEBUG, _("Got REQ_KEY origin %d.%d.%d.%d destination %d.%d.%d.%d from %s (%s)"),
-           IP_ADDR_V(from), IP_ADDR_V(to), cl->vpn_hostname, cl->real_hostname);
-
-  if((to & myself->vpn_mask) == (myself->vpn_ip & myself->vpn_mask))
-    {  /* hey! they want something from ME! :) */
-      send_key_answer(cl, from);
-      return 0;
-    }
-
-  fw = lookup_conn(to);
-  
-  if(!fw)
-    {
-      syslog(LOG_ERR, _("Attempting to forward REQ_KEY to %d.%d.%d.%d, which does not exist?"),
-	     IP_ADDR_V(to));
-      return -1;
-    }
-
-  if(debug_lvl > 1)
-    syslog(LOG_DEBUG, _("Forwarding REQ_KEY to %s (%s)"),
-	   fw->nexthop->vpn_hostname, fw->nexthop->real_hostname);
-  
-  cl->buffer[cl->reqlen-1] = '\n';
-  
-  if(write(fw->nexthop->meta_socket, cl->buffer, cl->reqlen) < 0)
-    {
-      syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__);
-      return -1;
-    }
-cp
-  return 0;
-}
-
-void set_keys(conn_list_t *cl, int expiry, char *key)
-{
-  char *ek;
-cp
-  if(!cl->public_key)
-    {
-      cl->public_key = xmalloc(sizeof(*cl->key));
-      cl->public_key->key = NULL;
-    }
-    
-  if(cl->public_key->key)
-    free(cl->public_key->key);
-  cl->public_key->length = strlen(key);
-  cl->public_key->expiry = expiry;
-  cl->public_key->key = xmalloc(cl->public_key->length + 1);
-  strcpy(cl->public_key->key, key);
-
-  ek = make_shared_key(key);
-  
-  if(!cl->key)
-    {
-      cl->key = xmalloc(sizeof(*cl->key));
-      cl->key->key = NULL;
-    }
-
-  if(cl->key->key)
-    free(cl->key->key);
-
-  cl->key->length = strlen(ek);
-  cl->key->expiry = expiry;
-  cl->key->key = xmalloc(cl->key->length + 1);
-  strcpy(cl->key->key, ek);
-cp
-}
-
-int ans_key_h(conn_list_t *cl)
-{
-  ip_t to;
-  ip_t from;
-  int expiry;
-  char *key;
-  conn_list_t *fw, *gk;
-cp
-  if(!cl->status.active)
-    {
-      syslog(LOG_ERR, _("Got unauthorized ANS_KEY from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
-      return -1;
-    }
-
-  if(sscanf(cl->buffer, "%*d %lx %lx %d %as", &to, &from, &expiry, &key) != 4)
-    {
-       syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
-       return -1;
-    }  
 
-  if(debug_lvl > 1)
-    syslog(LOG_DEBUG, _("Got ANS_KEY origin %d.%d.%d.%d destination %d.%d.%d.%d from %s (%s)"),
-            IP_ADDR_V(from), IP_ADDR_V(to), cl->vpn_hostname, cl->real_hostname);
-
-  if(to == myself->vpn_ip)
-    {  /* hey! that key's for ME! :) */
-      gk = lookup_conn(from);
-
-      if(!gk)
+      if(request_handlers[request](c))
+	/* Something went wrong. Probably scriptkiddies. Terminate. */
         {
-          syslog(LOG_ERR, _("Receiving ANS_KEY origin %d.%d.%d.%d from %s (%s), which does not exist?"),
-	         IP_ADDR_V(from), cl->vpn_hostname, cl->real_hostname);
+          syslog(LOG_ERR, _("Error while processing %s from %s (%s)"),
+		 request_name[request], c->name, c->hostname);
           return -1;
         }
-
-      set_keys(gk, expiry, key);
-      gk->status.validkey = 1;
-      gk->status.waitingforkey = 0;
-      flush_queues(gk);
-      return 0;
-    }
-
-  fw = lookup_conn(to);
-  
-  if(!fw)
-    {
-      syslog(LOG_ERR, _("Attempting to forward ANS_KEY to %d.%d.%d.%d, which does not exist?"),
-	     IP_ADDR_V(to));
-      return -1;
-    }
-
-  if(debug_lvl > 1)
-    syslog(LOG_DEBUG, _("Forwarding ANS_KEY to %s (%s)"),
-	   fw->nexthop->vpn_hostname, fw->nexthop->real_hostname);
-
-  cl->buffer[cl->reqlen-1] = '\n';
-
-  if((write(fw->nexthop->meta_socket, cl->buffer, cl->reqlen)) < 0)
-    {
-      syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__);
-      return -1;
-    }
-cp
-  return 0;
-}
-
-int key_changed_h(conn_list_t *cl)
-{
-  ip_t from;
-  conn_list_t *ik;
-cp
-  if(!cl->status.active)
-    {
-      syslog(LOG_ERR, _("Got unauthorized KEY_CHANGED from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
-      return -1;
     }
-
-  if(sscanf(cl->buffer, "%*d %lx", &from) != 1)
-    {
-       syslog(LOG_ERR, _("Got bad KEY_CHANGED from %s (%s)"),
-              cl->vpn_hostname, cl->real_hostname);
-       return -1;
-    }  
-
-  ik = lookup_conn(from);
-
-  if(!ik)
+  else
     {
-      syslog(LOG_ERR, _("Got KEY_CHANGED origin %d.%d.%d.%d from %s (%s), which does not exist?"),
-	     IP_ADDR_V(from), cl->vpn_hostname, cl->real_hostname);
+      syslog(LOG_ERR, _("Bogus data received from %s (%s)"),
+	     c->name, c->hostname);
       return -1;
     }
-
-  if(debug_lvl > 1)
-    syslog(LOG_DEBUG, _("Got KEY_CHANGED origin %s from %s (%s)"),
-            ik->vpn_hostname, cl->vpn_hostname, cl->real_hostname);
-
-  ik->status.validkey = 0;
-  ik->status.waitingforkey = 0;
-
-  notify_others(ik, cl, send_key_changed);
 cp
   return 0;
 }
 
-/* "Complete overhaul". */
+/* 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, ack_h,
   status_h, error_h, termreq_h,
-  add_host_h, del_host_h,
   ping_h, pong_h,
+//  add_node_h, del_node_h,
+  add_subnet_h, del_subnet_h,
+  add_edge_h, del_edge_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", "ACK",
   "STATUS", "ERROR", "TERMREQ",
-  "ADD_HOST", "DEL_HOST",
   "PING", "PONG",
+//  "ADD_NODE", "DEL_NODE",
+  "ADD_SUBNET", "DEL_SUBNET",
+  "ADD_EDGE", "DEL_EDGE",
+  "KEY_CHANGED", "REQ_KEY", "ANS_KEY",
+  "PACKET",
 };