Fix buffer overflow in meshlink_hint_address().

[meshlink] / src / meshlink.c

diff --git a/src/meshlink.c b/src/meshlink.c
index 601f49da910e61eebe941ef7646bb479d60fb1cd..6e2ca709b28679163d550d6890459904ed41d4a4 100644 (file)
--- a/src/meshlink.c
+++ b/src/meshlink.c
@@ -48,7 +48,6 @@ typedef struct {
 #endif
 
 static pthread_mutex_t global_mutex;
-static bool discovery_started;
 
 __thread meshlink_errno_t meshlink_errno;
 
@@ -874,17 +873,7 @@ bool meshlink_start(meshlink_handle_t *mesh) {
 
        mesh->threadstarted=true;
 
-       // Start discovery
-       // Since only one Avahi instance can run in one program at the moment, make sure we only start one, ignore it otherwise.
-
-       bool discovery_on = false;
-       pthread_mutex_lock(&global_mutex);
-       if(!discovery_started)
-               discovery_on = discovery_started = true;
-       pthread_mutex_unlock(&global_mutex);
-
-       if(discovery_on)
-               discovery_start(mesh);
+       discovery_start(mesh);
 
        return true;
 }
@@ -899,14 +888,7 @@ void meshlink_stop(meshlink_handle_t *mesh) {
        }
 
        // Stop discovery
-
-       bool discovery_on = mesh->discovery_threadstarted;
        discovery_stop(mesh);
-       if(discovery_on) {
-               pthread_mutex_lock(&global_mutex);
-               discovery_started = false;
-               pthread_mutex_unlock(&global_mutex);
-       }
 
        // Shut down a listening socket to signal the main thread to shut down
 
@@ -1695,39 +1677,21 @@ void meshlink_whitelist(meshlink_handle_t *mesh, meshlink_node_t *node) {
 /* Hint that a hostname may be found at an address
  * See header file for detailed comment.
  */
-extern void meshlink_hint_address(meshlink_handle_t *mesh, meshlink_node_t *node, struct sockaddr *addr) {
+extern void meshlink_hint_address(meshlink_handle_t *mesh, meshlink_node_t *node, const struct sockaddr *addr) {
        if(!mesh || !node || !addr)
                return;
        
-       char *addr_str = malloc(MAX_ADDRESS_LENGTH*sizeof(char));
-       memset(addr_str, 0, MAX_ADDRESS_LENGTH*sizeof(char));
-
-       char *port_str = malloc(MAX_PORT_LENGTH*sizeof(char));
-       memset(port_str, 0, MAX_PORT_LENGTH*sizeof(char));
-       
-       // extra byte for a space, and one to make sure string is null-terminated
-       int full_addr_len = MAX_ADDRESS_LENGTH + MAX_PORT_LENGTH + 2;
+       char *host = NULL, *port = NULL, *str = NULL;
+       sockaddr2str((const sockaddr_t *)addr, &host, &port);
 
-       char *full_addr_str = malloc(full_addr_len*sizeof(char));
-       memset(full_addr_str, 0, full_addr_len*sizeof(char));
-       
-       // get address and port number
-       if(!get_ip_str(addr, addr_str, MAX_ADDRESS_LENGTH))
-               goto fail;
-       if(!get_port_str(addr, port_str, MAX_ADDRESS_LENGTH))
-               goto fail;
-
-       // append_config_file expects an address, a space, and then a port number
-       strcat(full_addr_str, addr_str);
-       strcat(full_addr_str, " ");
-       strcat(full_addr_str, port_str);
-       
-       append_config_file(mesh, node->name, "Address", full_addr_str);
+       if(host && port) {
+               xasprintf(&str, "%s %s", host, port);
+               append_config_file(mesh, node->name, "Address", str);
+       }
 
-fail:
-       free(addr_str);
-       free(port_str);
-       free(full_addr_str);
+       free(str);
+       free(host);
+       free(port);
 
        // @TODO do we want to fire off a connection attempt right away?
 }