X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fprotocol.c;h=91c4ef3a8b634f5ce5d0d89aa6ac0ca46de0a5ac;hp=71b136769bb4819d4103cff7cecb4752aa812aa0;hb=4a7c2026aec6966f934b60d75bc472d28f8587d8;hpb=35932fe6c8cb481eb687f98424776ce429570c21

diff --git a/src/protocol.c b/src/protocol.c
index 71b13676..91c4ef3a 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 <ivo@o2w.nl>,
+                  2000,2001 Guus Sliepen <guus@sliepen.eu.org>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -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 1.28.4.47 2000/10/29 00:02:19 guus Exp $
+    $Id: protocol.c,v 1.28.4.131 2002/09/04 08:02:33 guus Exp $
 */
 
 #include "config.h"
@@ -27,28 +27,22 @@
 #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 <openssl/sha.h>
-#include <openssl/rand.h>
-
 #include "conf.h"
-#include "encr.h"
-#include "net.h"
-#include "netutl.h"
 #include "protocol.h"
 #include "meta.h"
-#include "connlist.h"
+#include "connection.h"
 
 #include "system.h"
 
+avl_tree_t *past_request_tree;
+
 int check_id(char *id)
 {
   int i;
@@ -56,1074 +50,205 @@ int check_id(char *id)
   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 *c, const char *format, ...)
 {
   va_list args;
   char buffer[MAXBUFSIZE];
   int len, request;
-
+  char *name = "everyone";
+  char *hostname = "broadcast";
 cp
-  /* Use vsnprintf instead of vasprintf: faster, no memory fragmentation, cleanup is automatic,
-     and there is a limit on the input buffer anyway */
+  if(c)
+    {
+      name = c->name;
+      hostname = c->hostname;
+    }
+
+  /* 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);
-  request = va_arg(args, int);
   va_end(args);
 
   if(len < 0 || len > MAXBUFSIZE-1)
     {
-      syslog(LOG_ERR, _("Output buffer overflow while sending %s to %s (%s)"), request_name[request], cl->name, cl->hostname);
+      syslog(LOG_ERR, _("Output buffer overflow while sending request to %s (%s)"), name, hostname);
       return -1;
     }
 
-  len++;
-
   if(debug_lvl >= DEBUG_PROTOCOL)
-    syslog(LOG_DEBUG, _("Sending %s to %s (%s)"), request_name[request], cl->name, cl->hostname);
+    {
+      sscanf(buffer, "%d", &request);
+      if(debug_lvl >= DEBUG_META)
+        syslog(LOG_DEBUG, _("Sending %s to %s (%s): %s"), request_name[request], name, hostname, buffer);
+      else
+        syslog(LOG_DEBUG, _("Sending %s to %s (%s)"), request_name[request], name, hostname);
+    }
 
+  buffer[len++] = '\n';
 cp
-  return send_meta(cl, buffer, len);
+  if(c)
+    return send_meta(c, buffer, len);
+  else
+    return broadcast_meta(NULL, buffer, len);
 }
 
-int receive_request(conn_list_t *cl)
+int receive_request(connection_t *c)
 {
   int request;
-cp  
-  if(sscanf(cl->buffer, "%d", &request) == 1)
+cp
+  if(sscanf(c->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"),
+	           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 >= 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], c->name, c->hostname, c->buffer);
+              else
+                syslog(LOG_DEBUG, _("Got %s from %s (%s)"),
+		       request_name[request], c->name, c->hostname);
+            }
 	}
 
-      if(request_handlers[request](cl))
+      if((c->allow_request != ALL) && (c->allow_request != request))
+        {
+          syslog(LOG_ERR, _("Unauthorized request from %s (%s)"), c->name, c->hostname);
+          return -1;
+        }
+
+      if(request_handlers[request](c))
 	/* Something went wrong. Probably scriptkiddies. Terminate. */
         {
           syslog(LOG_ERR, _("Error while processing %s from %s (%s)"),
-		 request_name[request], cl->name, cl->hostname);
+		 request_name[request], c->name, c->hostname);
           return -1;
         }
     }
   else
     {
       syslog(LOG_ERR, _("Bogus data received from %s (%s)"),
-	     cl->name, cl->hostname);
+	     c->name, c->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.
-*/
-
-int send_id(conn_list_t *cl)
+int past_request_compare(past_request_t *a, past_request_t *b)
 {
 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);
+  return strcmp(a->request, b->request);
 }
 
-int id_h(conn_list_t *cl)
+void free_past_request(past_request_t *r)
 {
-  conn_list_t *old;
-  config_t *cfg;
-cp
-  if(sscanf(cl->buffer, "%*d %as %d %lx %hd", &cl->name, &cl->protocol_version, &cl->options, &cl->port) != 4)
-    {
-       syslog(LOG_ERR, _("Got bad ID from %s"), cl->hostname);
-       return -1;
-    }
-
-  /* Check if version matches */
-
-  if(cl->protocol_version != myself->protocol_version)
-    {
-      syslog(LOG_ERR, _("Peer %s (%s) uses incompatible version %d"),
-             cl->name, cl->hostname, cl->protocol_version);
-      return -1;
-    }
-
-  /* Check if identity is a valid name */
-
-  if(check_id(cl->name))
-    {
-      syslog(LOG_ERR, _("Peer %s uses invalid identity name"), cl->hostname);
-      return -1;
-    }
-
-  /* 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.
-   */
+  if(r->request)
+    free(r->request);
+  free(r);
 cp
-  if(cl->status.outgoing)
-    {
-      if((old = lookup_id(cl->name)))
-        {
-          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;
-        }
-    }
-cp    
-  if((cfg = get_config_val(cl->config, publickey)))
-    {
-      cl->rsa_key = RSA_new();
-      BN_hex2bn(&cl->rsa_key->n, cfg->data.ptr);
-      BN_hex2bn(&cl->rsa_key->e, "FFFF");
-    }
-  else
-    {
-      syslog(LOG_ERR, _("No public key known for %s (%s)"), cl->name, cl->hostname);
-      return -1;
-    }
-cp
-  return send_challenge(cl);
 }
 
-int send_challenge(conn_list_t *cl)
+void init_requests(void)
 {
-  char *buffer;
-  int len, x;
 cp
-  len = RSA_size(cl->rsa_key);
-
-  /* Allocate buffers for the challenge */
-
-  buffer = xmalloc(len*2+1);
-
-  if(cl->hischallenge)
-    free(cl->hischallenge);
-    
-  cl->hischallenge = xmalloc(len);
+  past_request_tree = avl_alloc_tree((avl_compare_t)past_request_compare, (avl_action_t)free_past_request);
 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 */
-
-  bin2hex(buffer, buffer, len);
-  buffer[len*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)
+void exit_requests(void)
 {
-  char *buffer;
-  int len;
 cp
-  if(sscanf(cl->buffer, "%*d %as", &buffer) != 1)
-    {
-       syslog(LOG_ERR, _("Got bad CHALLENGE from %s (%s)"), cl->name, cl->hostname);
-       return -1;
-    }
-
-  len = RSA_size(myself->rsa_key);
-
-  /* Check if the length of the challenge is all right */
-
-  if(strlen(buffer) != len*2)
-    {
-      syslog(LOG_ERR, _("Intruder: wrong challenge length from %s (%s)"), cl->name, cl->hostname);
-      free(buffer);
-      return -1;
-    }
-
-  /* Allocate buffers for the challenge */
-
-  if(!cl->mychallenge)
-    cl->mychallenge = xmalloc(len);
-
-  /* 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;
-    }
-
-  if(debug_lvl >= DEBUG_SCARY_THINGS)
-    {
-      bin2hex(cl->mychallenge, buffer, len);
-      buffer[len*2] = '\0';
-      syslog(LOG_DEBUG, _("Received random challenge (unencrypted): %s"), buffer);
-    }
-
-  free(buffer);
-    
-  /* Rest is done by send_chal_reply() */
-cp
-  return send_chal_reply(cl);
-}
-
-int send_chal_reply(conn_list_t *cl)
-{
-  char hash[SHA_DIGEST_LENGTH*2+1];
-cp
-  if(!cl->mychallenge)
-    {
-      syslog(LOG_ERR, _("Trying to send CHAL_REPLY to %s (%s) without a valid CHALLENGE"), cl->name, cl->hostname);
-      return -1;
-    }
-     
-  /* Calculate the hash from the challenge we received */
-
-  SHA1(cl->mychallenge, RSA_size(myself->rsa_key), hash);
-
-  /* Convert the hash to a hexadecimal formatted string */
-
-  bin2hex(hash,hash,SHA_DIGEST_LENGTH);
-  hash[SHA_DIGEST_LENGTH*2] = '\0';
-
-  /* Send the reply */
-
-  if(cl->status.outgoing)
-    cl->allow_request = ID;
-  else
-    cl->allow_request = ACK;
-
+  avl_delete_tree(past_request_tree);
 cp
-  return send_request(cl, "%d %s", CHAL_REPLY, hash);
 }
 
-int chal_reply_h(conn_list_t *cl)
+int seen_request(char *request)
 {
-  char *hishash;
-  char myhash[SHA_DIGEST_LENGTH];
+  past_request_t p, *new;
 cp
-  if(sscanf(cl->buffer, "%*d %as", &hishash) != 1)
-    {
-       syslog(LOG_ERR, _("Got bad CHAL_REPLY from %s (%s)"), cl->name, cl->hostname);
-       free(hishash);
-       return -1;
-    }
-
-  /* Check if the length of the hash is all right */
-
-  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;
-    }
-
-  /* Convert the hash to binary format */
-
-  hex2bin(hishash, hishash, SHA_DIGEST_LENGTH);
+  p.request = request;
 
-  /* Calculate the hash from the challenge we sent */
-
-  SHA1(cl->hischallenge, RSA_size(cl->rsa_key), myhash);
-
-  /* Verify the incoming hash with the calculated hash */
-
-  if(memcmp(hishash, myhash, SHA_DIGEST_LENGTH))
+  if(avl_search(past_request_tree, &p))
     {
-      syslog(LOG_ERR, _("Intruder: wrong challenge reply from %s (%s)"), cl->name, cl->hostname);
       if(debug_lvl >= DEBUG_SCARY_THINGS)
-        {
-          bin2hex(myhash, hishash, SHA_DIGEST_LENGTH);
-          hishash[SHA_DIGEST_LENGTH*2] = '\0';
-          syslog(LOG_DEBUG, _("Expected challenge reply: %s"), hishash);
-        }
-      free(hishash);
-      return -1;
+        syslog(LOG_DEBUG, _("Already seen request"));
+      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.
-   */
-cp
-  if(cl->status.outgoing)
-      return send_ack(cl);
   else
-      return send_id(cl);
-}
-
-int send_ack(conn_list_t *cl)
-{
-cp
-  cl->allow_request = ACK;
-cp
-  return send_request(cl, "%d", ACK);
-}
-
-int ack_h(conn_list_t *cl)
-{
-  conn_list_t *old, *p;
-  subnet_t *s;
-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.
-   */
-
-  while((old = lookup_id(cl->name)))
-    {
-      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);
-
-      terminate_connection(old);
-    }
-
-  /* Activate this connection */
-
-  cl->allow_request = ALL;
-  cl->status.active = 1;
-  cl->nexthop = cl;
-
-  if(debug_lvl >= DEBUG_CONNECTIONS)
-    syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), cl->name, cl->hostname);
-
-cp
-  if(!cl->status.outgoing)
-    send_ack(cl);
-
-  /* Send him our subnets */
-  
-  for(s = myself->subnets; s; s = s->next)
-    send_add_subnet(cl, s);
-
-  /* And send him all the hosts and their subnets we know... */
-  
-  for(p = conn_list; p; p = p->next)
-    if(p != cl && p->status.active)
-      {
-        /* 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(s = p->subnets; s; s = s->next)
-          send_add_subnet(cl, s);
-      }
-cp
-  return 0;
-}
-
-/* Address and subnet information exchange */
-
-int send_add_subnet(conn_list_t *cl, subnet_t *subnet)
-{
-  int x;
-  char *netstr;
-cp
-  x = send_request(cl, "%d %s %s", ADD_SUBNET,
-                      subnet->owner->name, netstr = net2str(subnet));
-  free(netstr);
-cp
-  return x;
-}
-
-int add_subnet_h(conn_list_t *cl)
-{
-  char *subnetstr;
-  char *name;
-  conn_list_t *owner, *p;
-  subnet_t *subnet;
-cp
-  if(sscanf(cl->buffer, "%*d %as %as", &name, &subnetstr) != 2)
     {
-      syslog(LOG_ERR, _("Got bad ADD_SUBNET from %s (%s)"), cl->name, cl->hostname);
-      free(name); free(subnetstr);
-      return -1;
-    }
-
-  /* Check if owner name is a valid */
-
-  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;
-    }
-
-  /* Check if subnet string is valid */
-
-  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;
+      new = (past_request_t *)xmalloc(sizeof(*new));
+      new->request = xstrdup(request);
+      new->firstseen = now;
+      avl_insert(past_request_tree, new);
       return 0;
     }
-
-  /* Check if the owner of the new subnet is in the connection list */
-
-  if(!(owner = lookup_id(name)))
-    {
-      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(p = conn_list; p; p = p->next)
-    if(p->status.meta && p->status.active && p!= cl)
-      send_add_subnet(p, subnet);
-cp
-  return 0;
-}
-
-int send_del_subnet(conn_list_t *cl, subnet_t *subnet)
-{
-  int x;
-  char *netstr;
-cp
-  netstr = net2str(subnet);
-  x = send_request(cl, "%d %s %s", DEL_SUBNET, subnet->owner->name, netstr);
-  free(netstr);
-cp
-  return x;
-}
-
-int del_subnet_h(conn_list_t *cl)
-{
-  char *subnetstr;
-  char *name;
-  conn_list_t *owner, *p;
-  subnet_t *subnet;
-cp
-  if(sscanf(cl->buffer, "%*d %as %as", &name, &subnetstr) != 3)
-    {
-      syslog(LOG_ERR, _("Got bad DEL_SUBNET from %s (%s)"), cl->name, cl->hostname);
-      free(name); free(subnetstr);
-      return -1;
-    }
-
-  /* Check if owner name is a valid */
-
-  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;
-    }
-
-  /* Check if subnet string is valid */
-
-  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;
-    }
-
-  free(subnetstr);
-  
-  /* Check if somebody tries to add a subnet of ourself */
-
-  if(!strcmp(name, myself->name))
-    {
-      syslog(LOG_ERR, _("Warning: got DEL_SUBNET from %s (%s) for ourself, restarting"),
-             cl->name, cl->hostname);
-      free(name);
-      sighup = 1;
-      return 0;
-    }
-
-  /* Check if the owner of the new subnet is in the connection list */
-
-  if(!(owner = lookup_id(name)))
-    {
-      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(p = conn_list; p; p = p->next)
-    if(p->status.meta && 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)
-{
-cp
-  return send_request(cl, "%d %s %lx:%d %lx", ADD_HOST,
-                      other->name, other->address, other->port, other->options);
+cp  
 }
 
-int add_host_h(conn_list_t *cl)
+void age_past_requests(void)
 {
-  conn_list_t *old, *new;
-  conn_list_t *p;
-cp
-  new = new_conn_list();
-
-  if(sscanf(cl->buffer, "%*d %as %lx:%d %lx", &new->name, &new->address, &new->port, &new->options) != 4)
+  avl_node_t *node, *next;
+  past_request_t *p;
+  int left = 0, deleted = 0;
+cp 
+  for(node = past_request_tree->head; node; node = next)
     {
-       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))
-    {
-      syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s): invalid identity name"), cl->name, cl->hostname);
-      free_conn_list(new);
-      return -1;
-    }
-
-  /* Check if somebody tries to add ourself */
-
-  if(!strcmp(new->name, myself->name))
-    {
-      syslog(LOG_ERR, _("Warning: got ADD_HOST from %s (%s) for ourself, restarting"), cl->name, cl->hostname);
-      sighup = 1;
-      free_conn_list(new);
-      return 0;
-    }
-    
-  /* 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((new->address == old->address) && (new->port == old->port))
-        {
-          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);
-          free_conn_list(new);
-          return 0;
-        }
+      next = node->next;
+      p = (past_request_t *)node->data;
+      if(p->firstseen + pingtimeout < now)
+        avl_delete_node(past_request_tree, node), deleted++;
       else
-        {
-          if(debug_lvl >= DEBUG_CONNECTIONS)
-            syslog(LOG_NOTICE, _("Removing old entry for %s (%s) in favour of new connection"),
-                   old->name, old->hostname);
-
-          terminate_connection(old);
-        }
+        left++;
     }
 
-  /* Hook it up into the conn_list */
-
-  conn_list_add(new);
-
-  /* Tell the rest about the new host */
-
-  for(p = conn_list; p; p = p->next)
-    if(p->status.meta && p->status.active && p!=cl)
-      send_add_host(p, new);
-
-  /* Fill in rest of conn_list structure */
-
-  new->nexthop = cl;
-  new->status.active = 1;
-
+  if(debug_lvl >= DEBUG_SCARY_THINGS && left + deleted)
+    syslog(LOG_DEBUG, _("Aging past requests: deleted %d, left %d\n"), deleted, left);
 cp
-  return 0;
-}
-
-int send_del_host(conn_list_t *cl, conn_list_t *other)
-{
-cp
-  return send_request(cl, "%d %s %lx:%d %lx", DEL_HOST,
-                      other->name, other->address, other->port, other->options);
-}
-
-int del_host_h(conn_list_t *cl)
-{
-  char *name;
-  ip_t address;
-  port_t port;
-  long int options;
-  conn_list_t *old, *p;
-cp
-  if(sscanf(cl->buffer, "%*d %as %lx:%d %lx", &name, &address, &port, &options) != 4)
-    {
-      syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s)"),
-             cl->name, cl->hostname);
-      return -1;
-    }
-
-  /* Check if identity is a valid name */
-
-  if(check_id(name))
-    {
-      syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s): invalid identity name"), cl->name, cl->hostname);
-      free(name);
-      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);
-      sighup = 1;
-      return 0;
-    }
-
-  /* Check if the new 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);
-      return -1;
-    }
-  
-  /* Check if the rest matches */
-  
-  if(address!=old->address || port!=old->port || options!=old->options || cl!=old->nexthop)
-    {
-      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.active = 0;
-  terminate_connection(old);
-
-  /* Tell the rest about the new host */
-
-  for(p = conn_list; p; p = p->next)
-    if(p->status.meta && 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)
-{
-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->name, cl->hostname);
-       return -1;
-    }
-
-  if(debug_lvl >= DEBUG_STATUS)
-    {
-      syslog(LOG_NOTICE, _("Status message from %s (%s): %s: %s"),
-             cl->name, cl->hostname, status_text[statusno], statusstring);
-    }
-
-cp
-  free(statusstring);
-  return 0;
-}
-
-int send_error(conn_list_t *cl, int errno, char *errstring)
-{
-cp
-  if(!errstring)
-    errstring = strerror(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->name, cl->hostname);
-       return -1;
-    }
-
-  if(debug_lvl >= DEBUG_ERROR)
-    {
-      syslog(LOG_NOTICE, _("Error message from %s (%s): %s: %s"),
-             cl->name, cl->hostname, strerror(errno), errorstring);
-    }
-
-  free(errorstring);
-  terminate_connection(cl);
-cp
-  return 0;
-}
-
-int send_termreq(conn_list_t *cl)
-{
-cp
-  return send_request(cl, "%d", TERMREQ);
-}
-
-int termreq_h(conn_list_t *cl)
-{
-cp
-  terminate_connection(cl);
-cp
-  return 0;
-}
-
-/* Keepalive routines - FIXME: needs a closer look */
-
-int send_ping(conn_list_t *cl)
-{
-  cl->status.pinged = 1;
-cp
-  return send_request(cl, "%d", PING);
-}
-
-int ping_h(conn_list_t *cl)
-{
-cp
-  return send_pong(cl);
-}
-
-int send_pong(conn_list_t *cl)
-{
-cp
-  return send_request(cl, "%d", PONG);
-}
-
-int pong_h(conn_list_t *cl)
-{
-cp
-  cl->status.got_pong = 1;
-cp
-  return 0;
-}
-
-/* Key exchange */
-
-int send_key_changed(conn_list_t *from, conn_list_t *cl)
-{
-  conn_list_t *p;
-cp
-  for(p = conn_list; p != NULL; p = p->next)
-    {
-      if(p!=cl && p->status.meta && p->status.active)
-        send_request(p, "%d %s", KEY_CHANGED,
-                     from->name);
-    }
-cp
-  return 0;
-}
-
-int key_changed_h(conn_list_t *cl)
-{
-  char *from_id;
-  conn_list_t *from;
-cp
-  if(sscanf(cl->buffer, "%*d %as", &from_id) != 1)
-    {
-      syslog(LOG_ERR, _("Got bad KEY_CHANGED from %s (%s)"),
-             cl->name, cl->hostname);
-      return -1;
-    }
-
-  if(!(from = lookup_id(from_id)))
-    {
-      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;
-
-  send_key_changed(from, cl);
-cp
-  return 0;
-}
-
-int send_req_key(conn_list_t *from, conn_list_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)
-{
-  char *from_id, *to_id;
-  conn_list_t *from, *to;
-cp
-  if(sscanf(cl->buffer, "%*d %as %as", &from_id, &to_id) != 2)
-    {
-       syslog(LOG_ERR, _("Got bad REQ_KEY from %s (%s)"),
-              cl->name, cl->hostname);
-       return -1;
-    }
-
-  if(!(from = lookup_id(from_id)))
-    {
-      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))
-    {
-      send_ans_key(myself, from, myself->cipher_pktkey);
-    }
-  else
-    {
-      if(!(to = lookup_id(to_id)))
-        {
-          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);
-    }
-
-  free(from_id); free(to_id);
-cp
-  return 0;
-}
-
-int send_ans_key(conn_list_t *from, conn_list_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)
-{
-  char *from_id, *to_id, *pktkey;
-  int keylength;
-  conn_list_t *from, *to;
-cp
-  if(sscanf(cl->buffer, "%*d %as %as %as", &from_id, &to_id, &pktkey) != 3)
-    {
-       syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s)"),
-              cl->name, cl->hostname);
-       return -1;
-    }
-
-  if(!(from = lookup_id(from_id)))
-    {
-      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 */
-
-  if(!strcmp(to_id, myself->name))
-    {
-      /* It is for us, convert it to binary and set the key with it. */
-
-      keylength = strlen(pktkey);
-
-/* Don't do this... yet
-      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);
-*/
-
-      cl->status.validkey = 1;
-      cl->status.waitingforkey = 0;
-    }
-  else
-    {
-      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);
-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, ack_h,
   status_h, error_h, termreq_h,
   ping_h, pong_h,
-  add_host_h, del_host_h,
   add_subnet_h, del_subnet_h,
+  add_node_h, del_node_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",
   "PING", "PONG",
-  "ADD_HOST", "DEL_HOST",
   "ADD_SUBNET", "DEL_SUBNET",
+  "ADD_NODE", "DEL_NODE",
   "KEY_CHANGED", "REQ_KEY", "ANS_KEY",
-};
-
-/* Status strings */
-
-char (*status_text[]) = {
-  "Warning",
-};
-
-/* Error strings */
-
-char (*error_text[]) = {
-  "Error",
+  "PACKET",
 };