From 319e0cb48eb00565a11c85b901f54141f8160334 Mon Sep 17 00:00:00 2001 From: Guus Sliepen Date: Sun, 15 Jul 2001 18:07:31 +0000 Subject: [PATCH] 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. --- src/connection.c | 22 +++++++++++-- src/connection.h | 7 +++-- src/net.c | 4 +-- src/protocol.c | 80 +++++++++++++++++++++++------------------------- 4 files changed, 64 insertions(+), 49 deletions(-) diff --git a/src/connection.c b/src/connection.c index 8164cb4..c09ca94 100644 --- 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 f46d35b..4532eb4 100644 --- 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 4c5956e..8a0b7a2 100644 --- 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 ef60180..8d9a551 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 1.28.4.98 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); -- 2.25.1