X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fprotocol.c;h=78ab00d79a36cdb25da34255f338bd29574cb56a;hp=0b76cc3d7321d768fe16f590f72644b38388f014;hb=5afc1e98f436c4a2ed5da4b64293275b09632c79;hpb=c04c84c98055c6b9e9e7890d3992648a3b715a1a

diff --git a/src/protocol.c b/src/protocol.c
index 0b76cc3d..78ab00d7 100644
--- a/src/protocol.c
+++ b/src/protocol.c
@@ -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 1.28.4.30 2000/09/14 11:54:51 guus Exp $
+    $Id: protocol.c,v 1.28.4.34 2000/09/22 15:06:28 guus Exp $
 */
 
 #include "config.h"
@@ -36,6 +36,8 @@
 
 #include <netinet/in.h>
 
+#include <openssl/sha.h>
+
 #include "conf.h"
 #include "encr.h"
 #include "net.h"
@@ -44,40 +46,61 @@
 
 #include "system.h"
 
+int check_id(char *id)
+{
+  int i;
+
+  for (i = 0; i < strlen(id); i++)
+    {
+      if(!isalpha(id[i]) && id[i] != '_')
+        {
+          return 0;
+        }
+    }
+
+  return 1;
+}
+
 /* 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;
+  char buffer[MAXBUFSIZE+1];
+  int len;
+
 cp
-  if(debug_lvl >= DEBUG_PROTOCOL)
-    syslog(LOG_DEBUG, _("Sending %s to %s (%s)"), requestname[request], cl->id, cl->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 = vasprintf(&buffer, format, args);
+  va_start(args, request);
+  len = vsnprintf(buffer, MAXBUFSIZE+1, format, args);
   va_end(args);
 
-  if(len < 0 || !buffer)
+  if(len < 0 || len > MAXBUFSIZE)
     {
-      syslog(LOG_ERR, _("Error during vasprintf(): %m"));
+      syslog(LOG_ERR, _("Output buffer overflow while sending %s to %s (%s)"), request_name[request], cl->name, cl->hostname);
       return -1;
     }
 
   if(debug_lvl >= DEBUG_META)
-    syslog(LOG_DEBUG, _("Sending meta data to %s (%s): %s"), cl->id, cl->hostname, buffer);
+    syslog(LOG_DEBUG, _("Sending %s to %s (%s): %s"), request_name[request],
+           cl->name, cl->hostname, buffer);
+  else if(debug_lvl >= DEBUG_PROTOCOL)
+    syslog(LOG_DEBUG, _("Sending %s to %s (%s)"), request_name[request], cl->name, cl->hostname);
 
-  if(cl->status.encrypted)
+
+  if(cl->status.encryptin)
     {
       /* FIXME: Do encryption */
     }
 
-  if((write(cl->meta_socket, buffer, buflen)) < 0)
+  if((write(cl->meta_socket, buffer, len)) < 0)
     {
       syslog(LOG_ERR, _("Sending meta data failed:  %m"));
       return -1;
     }
-cp  
+cp
 }
 
 /* Connection protocol:
@@ -85,68 +108,84 @@ cp
    Client               Server
    send_id(u)
                         send_challenge(R)
-   send_chal_reply(BH)                   
-                        send_id(B)
-   send_challenge(BR)
-                        send_chal_reply(BH)
-   send_ack(B)
-			send_ack(B)
+   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,
-   (B) Blowfish.
+   (E) Encrypted with symmetric cipher.
 
-   Part of the challenge is directly used to set the blowfish key and the initial vector.
-   (Twee vliegen in één klap!)
-*/      
+   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 x;
+  char *optstr;
 cp
-  return send_request(cl, "%d %s %d %s", ID, myself->id, myself->version, opt2str(myself->options));
+  x = send_request(cl, "%d %s %d %s", ID, myself->name, myself->protocol_version, optstr=opt2str(myself->options));
+  free(optstr);
+cp
+  return x;
 }
 
 int id_h(conn_list_t *cl)
 {
   conn_list_t *old;
-  char *options;
+  char *optstr;
 cp
-  if(sscanf(cl->buffer, "%*d %as %d %as", &cl->id, &cl->version, &options) != 3)
+  if(sscanf(cl->buffer, "%*d %as %d %as", &cl->name, &cl->protocol_version, &optstr) != 3)
     {
        syslog(LOG_ERR, _("Got bad ID from %s"), cl->hostname);
        return -1;
     }
-    
+
   /* Check if version matches */
-  
-  if(cl->version != myself->version)
+
+  if(cl->protocol_version != myself->protocol_version)
     {
-      syslog(LOG_ERR, _("Peer %s uses incompatible version %d"), cl->hostname, cl->min_version, cl->max_version);
+      syslog(LOG_ERR, _("Peer %s (%s) uses incompatible version %d"),
+             cl->name, cl->hostname, cl->protocol_version);
       return -1;
     }
 
   /* Check if option string is valid */
-  
-  if((cl->options = str2opt(options)) == -1)
+
+  if((cl->options = str2opt(optstr)) == -1)
     {
       syslog(LOG_ERR, _("Peer %s uses invalid option string"), cl->hostname);
+      free(optstr);
       return -1;
     }
-    
+
+  free(optstr);
+
   /* Check if identity is a valid name */
-  
-  if(!check_id(cl->id))
+
+  if(!check_id(cl->name))
     {
       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);
+      syslog(LOG_ERR, _("Peer %s had unknown identity (%s)"), cl->hostname, cl->name);
       return -1;
     }
 
@@ -158,10 +197,10 @@ cp
 
   if(cl->status.outgoing)
     {
-      if((old=lookup_id(cl->id)))
+      if((old = lookup_id(cl->name)))
         {
           if(debug_lvl > DEBUG_CONNECTIONS)
-            syslog(LOG_NOTICE, _("Uplink %s (%s) is already in our connection list"), cl->id, cl->hostname);
+            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);
@@ -178,165 +217,135 @@ cp
 
 int send_challenge(conn_list_t *cl)
 {
-  char *buffer;
-  int keylength;
-  int x;
+  char buffer[CHAL_LENGTH*2+1];
 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->rsakey.n);
-  buffer = xmalloc(keylength*2);
+  /* Allocate buffers for the challenge */
 
-  /* Copy random data and the public key to the buffer */
-  
-  RAND_bytes(buffer, keylength);
-  BN_bn2bin(cl->rsakey.n, buffer+keylength);
+  if(!cl->hischallenge)
+    cl->hischallenge = xmalloc(CHAL_LENGTH);
 
-  /* If we don't have a blowfish key set yet, use the random data from the challenge to do so. */
-  
-  if(!cl->status.encrypted)
-    {
-      set_metakey(cl, buffer, keylength);
-    }
-
-  /* Calculate the hash from that */
+  /* Copy random data to the buffer */
 
-  SHA1(buffer, keylength*2, cl->chal_hash);
+  RAND_bytes(cl->hischallenge, CHAL_LENGTH);
 
   /* Convert the random data to a hexadecimal formatted string */
 
-  bin2hex(buffer,buffer,keylength);
+  bin2hex(cl->hischallenge,buffer,CHAL_LENGTH);
   buffer[keylength*2] = '\0';
 
   /* Send the challenge */
-  
+
   cl->allow_request = CHAL_REPLY;
-  x = send_request(cl, "%d %s", CHALLENGE, buffer);
-  free(buffer);
-  cl->status.encrypted = 1;
 cp
-  return x;
+  return send_request(cl, "%d %s", CHALLENGE, buffer);
 }
 
 int challenge_h(conn_list_t *cl)
 {
-  char *challenge;
+  char *buffer;
 cp
-  if(sscanf(cl->buffer, "%*d %as", &cl->id, &challenge) != 1)
+  if(sscanf(cl->buffer, "%*d %as", &buffer) != 1)
     {
-       syslog(LOG_ERR, _("Got bad CHALLENGE from %s (%s)"), cl->id, cl->hostname);
+       syslog(LOG_ERR, _("Got bad CHALLENGE from %s (%s)"), cl->name, 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->rsakey.n);
-
   /* Check if the length of the challenge is all right */
 
-  if(strlen(challenge) != keylength*2)
+  if(strlen(buffer) != CHAL_LENGTH*2)
     {
-      syslog(LOG_ERROR, _("Intruder: wrong challenge length from %s (%s)"), cl->id, cl->hostname);
+      syslog(LOG_ERR, _("Intruder: wrong challenge length from %s (%s)"), cl->name, cl->hostname);
+      free(buffer);
       return -1;
     }
 
-  /* Allocate buffers for the challenge and the hash */
-  
-  buffer = xmalloc(keylength*2);
-  hash = xmalloc(SHA_DIGEST_LEN*2+1);
+  /* Allocate buffers for the challenge */
 
-  /* Copy the incoming random data and our public key to the buffer */
+  if(!cl->mychallenge)
+    cl->mychallenge = xmalloc(CHAL_LENGTH);
 
-  hex2bin(challenge, buffer, keylength); 
-  BN_bn2bin(myself->rsakey.n, buffer+keylength);
+  /* Convert the challenge from hexadecimal back to binary */
 
-  /* Calculate the hash from that */
-  
-  SHA1(buffer, keylength*2, hash);
+  hex2bin(buffer,cl->mychallenge,CHAL_LENGTH);
+  free(buffer);
+    
+  /* Rest is done by send_chal_reply() */
+cp
+  return send_chal_reply(cl);
+}
 
-  /* If we don't have a blowfish key set yet, use the random data from the challenge to do so. */
-  
-  if(!cl->status.encrypted)
+int send_chal_reply(conn_list_t *cl)
+{
+  char hash[SHA_DIGEST_LENGTH*2+1];
+cp
+  if(!cl->mychallenge)
     {
-      set_metakey(cl, buffer, keylength);
-      cl->status.encrypted = 1;
+      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 */
 
-  free(buffer);
+  SHA1(cl->mychallenge, CHAL_LENGTH, hash);
 
   /* Convert the hash to a hexadecimal formatted string */
 
-  bin2hex(hash,hash,SHA_DIGEST_LEN);
-  hash[SHA_DIGEST_LEN*2] = '\0';
+  bin2hex(hash,hash,SHA_DIGEST_LENGTH);
+  hash[SHA_DIGEST_LENGTH*2] = '\0';
 
   /* Send the reply */
 
   if(cl->status.outgoing)
-    cl->allow_resuest = ID;
+    cl->allow_request = ID;
   else
     cl->allow_request = ACK;
 
-  x = send_request(cl, "%d %s", CHAL_REPLY, hash);
-  free(hash);
 cp
-  return x;
-} 
+  return send_request(cl, "%d %s", CHAL_REPLY, hash);
+}
 
 int chal_reply_h(conn_list_t *cl)
 {
-  char *hash;
+  char *hishash;
+  char myhash[SHA_DIGEST_LENGTH];
 cp
-  if(sscanf(cl->buffer, "%*d %as", &cl->id, &hash) != 2)
+  if(sscanf(cl->buffer, "%*d %as", &hishash) != 2)
     {
-       syslog(LOG_ERR, _("Got bad CHAL_REPLY from %s (%s)"), cl->id, cl->hostname);
+       syslog(LOG_ERR, _("Got bad CHAL_REPLY from %s (%s)"), cl->name, cl->hostname);
        return -1;
     }
 
   /* Check if the length of the hash is all right */
-  
-  if(strlen(hash) != SHA_DIGEST_LEN*2)
+
+  if(strlen(hishash) != SHA_DIGEST_LENGTH*2)
     {
-      syslog(LOG_ERROR, _("Intruder: wrong challenge reply length from %s (%s)"), cl->id, cl->hostname);
+      syslog(LOG_ERR, _("Intruder: wrong challenge reply length from %s (%s)"), cl->name, cl->hostname);
       return -1;
     }
-    
+
   /* Convert the hash to binary format */
-  
-  hex2bin(hash, hash, SHA_DIGEST_LEN);
-  
+
+  hex2bin(hishash, hishash, SHA_DIGEST_LENGTH);
+
+  /* Calculate the hash from the challenge we sent */
+
+  SHA1(cl->hischallenge, CHAL_LENGTH, myhash);
+
   /* Verify the incoming hash with the calculated hash */
-  
-  if{!memcmp(hash, cl->chal_hash, SHA_DIGEST_LEN)}
+
+  if(!memcmp(hishash, myhash, SHA_DIGEST_LENGTH))
     {
-      syslog(LOG_ERROR, _("Intruder: wrong challenge reply from %s (%s)"), cl->id, cl->hostname);
+      syslog(LOG_ERR, _("Intruder: wrong challenge reply from %s (%s)"), cl->name, cl->hostname);
+      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.
    */
-   
-  free(hash);
-  free(cl->chal_hash);
-
 cp
   if(cl->status.outgoing)
     {
@@ -358,18 +367,18 @@ cp
 
 int ack_h(conn_list_t *cl)
 {
-  conn_list_t old;
+  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
+     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->id))) 
+  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->id, old->hostname, cl->hostname);
+        cl->name, old->hostname, cl->hostname);
       old->status.active = 0;
       terminate_connection(old);
     }
@@ -380,7 +389,7 @@ cp
   cl->status.active = 1;
 
   if(debug_lvl > DEBUG_CONNECTIONS)
-    syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), cl->id, cl->hostname);
+    syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), cl->name, cl->hostname);
 
   /* Exchange information about other tinc daemons */
 
@@ -400,88 +409,242 @@ cp
 
 int send_add_subnet(conn_list_t *cl, conn_list_t *other, subnet_t *subnet)
 {
+  int x;
+  char *netstr;
+cp
+  x = send_request(cl, "%d %s %s", ADD_SUBNET,
+                      other->name, netstr = net2str(subnet));
+  free(netstr);
 cp
-  return send_request(cl, "%d %s %d %s", ADD_SUBNET, other->id, subnet->type, net2str(subnet));
+  return x;
 }
 
 int add_subnet_h(conn_list_t *cl)
 {
+  char *subnetstr;
+  char *name;
+  conn_list_t *owner;
+  subnet_t *subnet, *old;
+cp
+  if(sscanf(cl->buffer, "%*d %as %as", &name, &subnetstr) != 3)
+    {
+      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)) == -1)
+    {
+      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;
+    }
+
+  /* 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 */
+cp
+  return subnet_add(owner, subnet);
 }
 
 int send_del_subnet(conn_list_t *cl, conn_list_t *other, subnet_t *subnet)
 {
 cp
-  return send_request(cl, "%d %s %d %s", DEL_SUBNET, other->id, subnet->type, net2str(subnet));
+  return send_request(cl, "%d %s %s", DEL_SUBNET, other->name, net2str(subnet));
 }
 
 int del_subnet_h(conn_list_t *cl)
 {
+  char *subnetstr;
+  char *name;
+  conn_list_t *owner;
+  subnet_t *subnet, *old;
+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)) == -1)
+    {
+      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, add the subnet to the list of the owner */
+cp
+  return subnet_del(owner, subnet);
 }
 
 /* New and closed connections notification */
 
 int send_add_host(conn_list_t *cl, conn_list_t *other)
 {
+  char *optstr;
+  int x;
+cp
+  x = send_request(cl, "%d %s %s %lx:%d %s", ADD_HOST,
+                      myself->name, other->name, other->real_ip, other->port, optstr = opt2str(other->options));
+  free(optstr);
 cp
-  return send_request(cl, "%d %s %lx:%d %s", ADD_HOST, other->id, other->address, other->port, opt2str(other->options));
+  return x;
 }
 
 int add_host_h(conn_list_t *cl)
 {
-  char *options;
-  conn_list_t *old, *new;
+  char *optstr;
+  char *sender;
+  conn_list_t *old, *new, *hisuplink;
 cp
   new = new_conn_list();
 
-  if(sscanf(cl->buffer, "%*d %as %lx:%d %as", &new->id, &new->address, &new->port, &options) != 4)
+  if(sscanf(cl->buffer, "%*d %as %as %lx:%d %as", &sender, &new->name, &new->address, &new->port, &optstr) != 5)
     {
-       syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s)"), cl->id, cl->hostname);
+       syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s)"), cl->name, cl->hostname);
        return -1;
-    }  
+    }
 
   /* Check if option string is valid */
-  
-  if((new->options = str2opt(options) == -1)
+
+  if((new->options = str2opt(optstr)) == -1)
     {
-      syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s): invalid option string"), cl->hostname);
+      syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s): invalid option string"), cl->name, cl->hostname);
+      free(optstr); free(sender);
       return -1;
     }
 
+  free(optstr);
+
   /* Check if identity is a valid name */
-  
-  if(!check_id(new->id))
+
+  if(!check_id(new->name) || !check_id(sender))
     {
-      syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s): invalid identity name"), cl->id, cl->hostname);
+      syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s): invalid identity name"), cl->name, cl->hostname);
+      free(sender);
       return -1;
     }
-    
+
   /* Check if somebody tries to add ourself */
-  
-  if(!strcmp(new->id, myself->id))
+
+  if(!strcmp(new->name, myself->name))
     {
-      syslog(LOG_ERR, _("Warning: got ADD_HOST from %s (%s) for ourself, restarting"), cl->id, cl->hostname);
+      syslog(LOG_ERR, _("Warning: got ADD_HOST from %s (%s) for ourself, restarting"), cl->name, cl->hostname);
       sighup = 1;
+      free(sender);
       return 0;
     }
 
+  /* We got an ADD_HOST from ourself!? */
+
+  if(!strcmp(sender, 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;
+    }
+
+  /* Lookup his uplink */
+
+  if(!(new->hisuplink = lookup_id(sender))
+    {
+      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);
+      return -1;
+    }
+    
+  free(sender);
+
   /* Fill in more of the new conn_list structure */
 
-  new->hostname = hostlookup(htonl(new->address));
-  
+  new->hostname = hostlookup(htonl(new->real_ip));
+
   /* Check if the new host already exists in the connnection list */
 
-  if((old = lookup_id(id))
+  if((old = lookup_id(new->name)))
     {
-      if((new->address == old->address) && (new->port == old->port))
+      if((new->real_ip == old->real_ip) && (new->port == old->port))
         {
           if(debug_lvl > DEBUG_CONNECTIONS)
-            syslog(LOG_NOTICE, _("Got duplicate ADD_HOST for %s (%s) from %s (%s)"), old->id, old->hostname, new->id, new->hostname);
-	  return 0;
+            syslog(LOG_NOTICE, _("Got duplicate ADD_HOST for %s (%s) from %s (%s)"),
+                   old->name, old->hostname, new->name, new->hostname);
+          return 0;
         }
       else
         {
           if(debug_lvl > DEBUG_CONNECTIONS)
-            syslog(LOG_NOTICE, _("Removing old entry for %s (%s)"), old->id, old->hostname);
+            syslog(LOG_NOTICE, _("Removing old entry for %s (%s)"),
+                   old->name, old->hostname);
           old->status.active = 0;
           terminate_connection(old);
         }
@@ -489,70 +652,128 @@ cp
 
   /* Fill in rest of conn_list structure */
 
-  new->nexthop = cl;
+  new->myuplink = cl;
   new->status.active = 1;
-  
+
   /* Hook it up into the conn_list */
 
   conn_list_add(conn_list, new);
 
   /* Tell the rest about the new host */
-  
+
   notify_others(new, cl, send_add_host);
-  
+
 cp
   return 0;
 }
 
 int send_del_host(conn_list_t *cl, conn_list_t *other)
 {
+  char *optstr;
+  int x;
 cp
-  return send_request(cl, "%d %s %lx:%d", DEL_HOST, other->id, other->address, other->port);
+  x = send_request(cl, "%d %s %s %lx:%d %s", DEL_HOST,
+                      myself->name, other->name, other->real_ip, other->port, optstr = opt2str(other->options));
+  free(optstr);
+cp
+  return x;
 }
 
 int del_host_h(conn_list_t *cl)
 {
-  char *id;
+  char *name;
+  char *sender;
+  char *opstr;
   ip_t address;
   port_t port;
-  conn_list_t *old;
+  int options;
+  conn_list_t *old, *hisuplink;
+
 cp
-  if(sscanf(cl->buffer, "%*d %as %lx:%d", &id, &address, &port) != 3)
+  if(sscanf(cl->buffer, "%*d %as %as %lx:%d %as", &sender, &name, &address, &port, &optstr) != 5)
     {
-       syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s)"), cl->id, cl->hostname);
-       return -1;
-    }  
+      syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s)"),
+             cl->name, cl->hostname);
+      return -1;
+    }
+
+  /* Check if option string is valid */
+
+  if((options = str2opt(optstr)) == -1)
+    {
+      syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s): invalid option string"), cl->name, cl->hostname);
+      free(optstr); free(sender); free(name);
+      return -1;
+    }
+
+  free(optstr);
+      
+  /* Check if identity is a valid name */
+
+  if(!check_id(name) || !check_id(sender))
+    {
+      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(id, myself->id))
+
+  if(!strcmp(name, myself->name))
     {
-      syslog(LOG_ERR, _("Warning: got DEL_HOST from %s (%s) for ourself, restarting"), cl->id, cl->hostname);
+      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;
     }
 
-  /* Check if the new host already exists in the connnection list */
+  /* We got an ADD_HOST from ourself!? */
 
-  if((old = lookup_id(id))
+  if(!strcmp(sender, myself->name))
     {
-      if((address == old->address) && (port == old->port))
-        {
-          notify_others(old, cl, send_del_host);
+      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;
+    }
 
-          fw->status.termreq = 1;
-          fw->status.active = 0;
+  /* Lookup his uplink */
 
-          terminate_connection(fw);
-cp
-          return 0;
-        }
+  if(!(hisuplink = lookup_id(sender))
+    {
+      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);
+      return -1;
     }
+    
+  free(sender);
 
-  if(debug_lvl > DEBUG_CONNECTIONS)
+  /* Check if the new host already exists in the connnection list */
+
+  if(!(old = lookup_id(name)))
     {
-      syslog(LOG_NOTICE, _("Got DEL_HOST for %s from %s (%s) which is not in our connection list"), id, cl->id, cl->hostname);
+      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 || hisuplink!=old->hisuplink || cl!=old->myuplink)
+    {
+      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);
 cp
   return 0;
 }
@@ -575,13 +796,15 @@ int status_h(conn_list_t *cl)
 cp
   if(sscanf(cl->buffer, "%*d %d %as", &statusno, &statusstring) != 2)
     {
-       syslog(LOG_ERR, _("Got bad STATUS from %s (%s)"), cl->id, cl->hostname);
+       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->id, cl->hostname, status_text[statusno], statusstring);
+      syslog(LOG_NOTICE, _("Status message from %s (%s): %s: %s"),
+             cl->name, cl->hostname, status_text[statusno], statusstring);
     }
 
 cp
@@ -592,8 +815,8 @@ cp
 int send_error(conn_list_t *cl, int errno, char *errstring)
 {
 cp
-  if(!errorstring)
-    errorstring = error_text[errno];
+  if(!errstring)
+    errstring = strerror(errno);
   return send_request(cl, "%d %d %s", ERROR, errno, errstring);
 }
 
@@ -604,13 +827,15 @@ int error_h(conn_list_t *cl)
 cp
   if(sscanf(cl->buffer, "%*d %d %as", &errno, &errorstring) != 2)
     {
-       syslog(LOG_ERR, _("Got bad error from %s (%s)"), cl->id, cl->hostname);
+       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->id, cl->hostname, error_text[errno], errorstring);
+      syslog(LOG_NOTICE, _("Error message from %s (%s): %s: %s"),
+             cl->name, cl->hostname, strerror(errno), errorstring);
     }
 
   free(errorstring);
@@ -673,7 +898,8 @@ 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->id);
+        send_request(p, "%d %s", KEY_CHANGED,
+                     from->name);
     }
 cp
   return 0;
@@ -686,31 +912,34 @@ int key_changed_h(conn_list_t *cl)
 cp
   if(sscanf(cl->buffer, "%*d %as", &from_id) != 1)
     {
-       syslog(LOG_ERR, _("Got bad KEY_CHANGED from %s (%s)"), cl->id, cl->hostname);
-       return -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->id, cl->hostname, 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->id, to->id);
+  return send_request(to->nexthop, "%d %s %s", REQ_KEY,
+                      from->name, to->name);
 }
 
 int req_key_h(conn_list_t *cl)
@@ -720,28 +949,31 @@ int req_key_h(conn_list_t *cl)
 cp
   if(sscanf(cl->buffer, "%*d %as %as", &from_id, &to_id) != 2)
     {
-       syslog(LOG_ERR, _("Got bad REQ_KEY from %s (%s)"), cl->id, cl->hostname);
+       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->id, cl->hostname, 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(id, myself->strcmp))
+  if(!strcmp(to_id, myself->name))
     {
-      send_ans_key(myself, from, myself->datakey);
+      send_ans_key(myself, from, myself->datakey->key);
     }
   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->id, cl->hostname, 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;
         }
@@ -756,7 +988,8 @@ cp
 int send_ans_key(conn_list_t *from, conn_list_t *to, char *datakey)
 {
 cp
-  return send_request(to->nexthop, "%d %s %s %s", ANS_KEY, from->id, to->id, datakey);
+  return send_request(to->nexthop, "%d %s %s %s", ANS_KEY,
+                      from->name, to->name, datakey);
 }
 
 int ans_key_h(conn_list_t *cl)
@@ -767,28 +1000,31 @@ int ans_key_h(conn_list_t *cl)
 cp
   if(sscanf(cl->buffer, "%*d %as %as %as", &from_id, &to_id, &datakey) != 3)
     {
-       syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s)"), cl->id, cl->hostname);
+       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->id, cl->hostname, 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(datakey);
       return -1;
     }
 
   /* Check if this key request is for us */
 
-  if(!strcmp(id, myself->strcmp))
+  if(!strcmp(to_id, myself->name))
     {
       /* It is for us, convert it to binary and set the key with it. */
-      
+
       keylength = strlen(datakey);
-      
+
       if((keylength%2) || (keylength <= 0))
         {
-          syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s) origin %s: invalid key"), cl->id, cl->hostname, from->id);
+          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(datakey);
           return -1;
         }
@@ -800,7 +1036,8 @@ cp
     {
       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->id, cl->hostname, 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(datakey);
           return -1;
         }
@@ -821,7 +1058,7 @@ cp
 */
 
 int notify_others(conn_list_t *new, conn_list_t *source,
-		  int (*function)(conn_list_t*, conn_list_t*))
+                  int (*function)(conn_list_t*, conn_list_t*))
 {
   conn_list_t *p;
 cp