Split connection list into two lists:

 - one list to handle all incoming/outgoing TCP connections
 - another list to handle all UDP connections

This will prevent race conditions.

diff --git a/src/connection.c b/src/connection.c
index 8164cb4bba029aad06c9b32ba97f38cfc53a427e..c09ca94aec1d678597005e477220194de68c477a 100644 (file)
--- a/src/connection.c
+++ b/src/connection.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: connection.c,v 1.1.2.12 2001/06/29 13:09:55 guus Exp $
+    $Id: connection.c,v 1.1.2.13 2001/07/15 18:07:31 guus Exp $
 */
 
 #include "config.h"
@@ -42,6 +42,7 @@
 /* Root of the connection list */
 
 avl_tree_t *connection_tree;
+avl_tree_t *active_tree;
 avl_tree_t *id_tree;
 
 /* Pointer to connection describing myself */
@@ -51,6 +52,11 @@ connection_t *myself = NULL;
 /* Initialization and callbacks */
 
 int connection_compare(connection_t *a, connection_t *b)
+{
+  return a->meta_socket - b->meta_socket;
+}
+
+int active_compare(connection_t *a, connection_t *b)
 {
   ipv4_t result;
 
@@ -69,6 +75,7 @@ int id_compare(connection_t *a, connection_t *b)
 void init_connections(void)
 {
   connection_tree = avl_alloc_tree((avl_compare_t)connection_compare, (avl_action_t)free_connection);
+  active_tree = avl_alloc_tree((avl_compare_t)active_compare, NULL);
   id_tree = avl_alloc_tree((avl_compare_t)id_compare, NULL);
 }
 
@@ -130,6 +137,7 @@ void destroy_connection_tree(void)
 {
 cp
   avl_delete_tree(id_tree);
+  avl_delete_tree(active_tree);
   avl_delete_tree(connection_tree);
 cp
 }
@@ -143,6 +151,13 @@ cp
 cp
 }
 
+void active_add(connection_t *cl)
+{
+cp
+  avl_insert(active_tree, cl);
+cp
+}
+
 void id_add(connection_t *cl)
 {
 cp
@@ -154,20 +169,21 @@ void connection_del(connection_t *cl)
 {
 cp
   avl_delete(id_tree, cl);
+  avl_delete(active_tree, cl);
   avl_delete(connection_tree, cl);
 cp
 }
 
 /* Lookup functions */
 
-connection_t *lookup_connection(ipv4_t address, short unsigned int port)
+connection_t *lookup_active(ipv4_t address, short unsigned int port)
 {
   connection_t cl;
 cp
   cl.address = address;
   cl.port = port;
 
-  return avl_search(connection_tree, &cl);
+  return avl_search(active_tree, &cl);
 }
 
 connection_t *lookup_id(char *name)

diff --git a/src/connection.h b/src/connection.h
index f46d35b808128d1a583707670568cd6fba5418ca..4532eb49024c249496afd89057c85d4ad4cb2549 100644 (file)
--- a/src/connection.h
+++ b/src/connection.h
@@ -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: connection.h,v 1.1.2.9 2001/05/25 11:54:28 guus Exp $
+    $Id: connection.h,v 1.1.2.10 2001/07/15 18:07:31 guus Exp $
 */
 
 #ifndef __TINC_CONNECTION_H__
@@ -65,6 +65,7 @@ typedef struct status_bits_t {
 typedef struct connection_t {
   char *name;                      /* name of this connection */
   ipv4_t address;                  /* his real (internet) ip */
+  short unsigned int meta_port;    /* port number of meta connection */
   char *hostname;                  /* the hostname of its real ip */
   int protocol_version;            /* used protocol */
   short unsigned int port;         /* port number for UDP traffic */
@@ -103,16 +104,18 @@ typedef struct connection_t {
 } connection_t;
 
 extern avl_tree_t *connection_tree;
+extern avl_tree_t *active_tree;
 extern connection_t *myself;
 
 extern void init_connections(void);
 extern connection_t *new_connection(void);
 extern void free_connection(connection_t *);
 extern void id_add(connection_t *);
+extern void active_add(connection_t *);
 extern void connection_add(connection_t *);
 extern void connection_del(connection_t *);
 extern connection_t *lookup_id(char *);
-extern connection_t *lookup_connection(ipv4_t, short unsigned int);
+extern connection_t *lookup_active(ipv4_t, short unsigned int);
 extern void dump_connection_list(void);
 extern int read_host_config(connection_t *);
 extern void destroy_connection_tree(void);

diff --git a/src/net.c b/src/net.c
index 4c5956e8b9fc324a302c59d7fe850cf400f1d2f2..8a0b7a2bc05f5e2b2d64f738676a0e8631df379b 100644 (file)
--- a/src/net.c
+++ b/src/net.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: net.c,v 1.35.4.119 2001/07/15 14:21:12 guus Exp $
+    $Id: net.c,v 1.35.4.120 2001/07/15 18:07:31 guus Exp $
 */
 
 #include "config.h"
@@ -1113,7 +1113,7 @@ cp
       return;
     }
 
-  cl = lookup_connection(ntohl(from.sin_addr.s_addr), ntohs(from.sin_port));
+  cl = lookup_active(ntohl(from.sin_addr.s_addr), ntohs(from.sin_port));
 
   if(!cl)
     {

diff --git a/src/protocol.c b/src/protocol.c
index ef6018020cd066f77d31801fefb459771b9aef09..8d9a551c939daa3901075cd6162ca90477c65397 100644 (file)
--- 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 1.28.4.98 2001/07/04 08:41:36 guus Exp $
+    $Id: protocol.c,v 1.28.4.99 2001/07/15 18:07:31 guus Exp $
 */
 
 #include "config.h"
@@ -174,11 +174,9 @@ cp
 int id_h(connection_t *cl)
 {
   connection_t *old;
-  unsigned short int port;
   char name[MAX_STRING_SIZE];
-  avl_node_t *node;
 cp
-  if(sscanf(cl->buffer, "%*d "MAX_STRING" %d %lx %hd", name, &cl->protocol_version, &cl->options, &port) != 4)
+  if(sscanf(cl->buffer, "%*d "MAX_STRING" %d %lx %hd", name, &cl->protocol_version, &cl->options, &cl->port) != 4)
     {
        syslog(LOG_ERR, _("Got bad ID from %s"), cl->hostname);
        return -1;
@@ -208,6 +206,17 @@ cp
     
   cl->name = xstrdup(name);
 
+  /* Make sure we don't make an outgoing connection to a host that is already in our connection list */
+
+  if(cl->status.outgoing)
+    if((old = lookup_id(cl->name)))
+      {
+        if(debug_lvl >= DEBUG_CONNECTIONS)
+          syslog(LOG_NOTICE, _("We are already connected to %s."), cl->name);
+        old->status.outgoing = 1;
+        return -1;
+      }
+    
   /* Load information about peer */
 
   if(read_host_config(cl))
@@ -216,40 +225,6 @@ cp
       return -1;
     }
 
-  /* First check if the host is already in our
-     connection list. If so, we are probably making a loop, which
-     is not desirable.
-   */
-
-  if((old = lookup_id(cl->name)))
-    {
-      if(debug_lvl >= DEBUG_CONNECTIONS)
-        syslog(LOG_NOTICE, _("%s (%s) is already in our connection list"), cl->name, cl->hostname);
-      if(cl->status.outgoing)
-        {
-          cl->status.outgoing = 0;
-          old->status.outgoing = 1;
-        }
-      terminate_connection(cl);
-      return 0;
-    }
-    
-  /* Now we can add the name to the id tree */
-  
-  id_add(cl);
-
-  /* And uhr... cl->port just changed so we have to unlink it from the connection tree and re-insert... */
-  
-  node = avl_unlink(connection_tree, cl);
-  cl->port = port;
-  if(!avl_insert_node(connection_tree, node))
-    {
-      old = avl_search_node(connection_tree, node)->data;
-      syslog(LOG_ERR, _("%s is listening on %s:%hd, which is already in use by %s!"),
-             cl->name, cl->hostname, cl->port, old->name);
-      return -1;
-    }
-    
   /* Read in the public key, so that we can send a metakey */
 
   if(read_rsa_public_key(cl))
@@ -272,15 +247,34 @@ cp
      old connection that has timed out but we don't know it yet.
    */
 
-  while((old = lookup_id(cl->name)))
+  if((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);
-
+        syslog(LOG_NOTICE, _("Removing old connection for %s at %s in favour of new connection from %s"),
+               cl->name, old->hostname, cl->hostname);
+      if(old->status.outgoing)
+        {
+          cl->status.outgoing = 1;
+          old->status.outgoing = 0;
+        }
       terminate_connection(old);
+      return 0;
     }
+    
+  /* Now we can add the name to the id tree */
+  
+  id_add(cl);
 
+  /* Also check if no other tinc daemon uses the same IP and port for UDP traffic */
+  
+  old = avl_search(active_tree, cl);
+  if(old)
+  {
+    syslog(LOG_ERR, _("%s is listening on %s:%hd, which is already in use by %s!"),
+           cl->name, cl->hostname, cl->port, old->name);
+    return -1;
+  }
+    
   /* Activate this connection */
 
   cl->allow_request = ALL;
@@ -289,6 +283,8 @@ cp
   cl->cipher_pkttype = EVP_bf_cbc();
   cl->cipher_pktkeylength = cl->cipher_pkttype->key_len + cl->cipher_pkttype->iv_len;
 
+  active_add(cl);
+
   if(debug_lvl >= DEBUG_CONNECTIONS)
     syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), cl->name, cl->hostname);