kernel-interface: Reallocate previously used reqids

This is mainly an issue on FreeBSD where the current kernel still only
allows the daemon to use reqids < IPSEC_MANUAL_REQID_MAX (0x3fff = 16383).

Fixes #2315.

diff --git a/src/libcharon/kernel/kernel_interface.c b/src/libcharon/kernel/kernel_interface.c
index e216c972cfbfd79ae88d30a174431bc917b7a85c..ced026dfc3a121eb60292e2cf6f41f4de9088b14 100644 (file)
--- a/src/libcharon/kernel/kernel_interface.c
+++ b/src/libcharon/kernel/kernel_interface.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2008-2016 Tobias Brunner
+ * Copyright (C) 2008-2019 Tobias Brunner
  * HSR Hochschule fuer Technik Rapperswil
  *
  * Copyright (C) 2010 Martin Willi
@@ -126,6 +126,11 @@ struct private_kernel_interface_t {
         */
        hashtable_t *reqids_by_ts;
 
+       /**
+        * Previously used reqids that have been released
+        */
+       array_t *released_reqids;
+
        /**
         * mutex for algorithm mappings
         */
@@ -382,7 +387,10 @@ METHOD(kernel_interface_t, alloc_reqid, status_t,
                {
                        /* none found, create a new entry, allocating a reqid */
                        entry = tmpl;
-                       entry->reqid = ++counter;
+                       if (!array_remove(this->released_reqids, ARRAY_HEAD, &entry->reqid))
+                       {
+                               entry->reqid = ++counter;
+                       }
                        this->reqids_by_ts->put(this->reqids_by_ts, entry, entry);
                        this->reqids->put(this->reqids, entry, entry);
                }
@@ -412,6 +420,8 @@ METHOD(kernel_interface_t, release_reqid, status_t,
        {
                if (--entry->refs == 0)
                {
+                       array_insert_create_value(&this->released_reqids, sizeof(uint32_t),
+                                                                         ARRAY_TAIL, &entry->reqid);
                        entry = this->reqids_by_ts->remove(this->reqids_by_ts, entry);
                        if (entry)
                        {
@@ -996,6 +1006,7 @@ METHOD(kernel_interface_t, destroy, void,
        DESTROY_FUNCTION_IF(this->ifaces_filter, (void*)free);
        this->reqids->destroy(this->reqids);
        this->reqids_by_ts->destroy(this->reqids_by_ts);
+       array_destroy(this->released_reqids);
        this->listeners->destroy(this->listeners);
        this->mutex->destroy(this->mutex);
        free(this);