random: keep global list of initialized contexts

This allows to properly deinitialize all random generator
contexts on library deinitialization.

Signed-off-by: Nikos Mavrogiannopoulos <nmav@redhat.com>

diff --git a/lib/random.c b/lib/random.c
index 73fb143d7f1f0c7b16d36caad010635f0bddb2ba..2fe82adc7d7bb4cf55fdbf415d301a9a50df2f4b 100644 (file)
--- a/lib/random.c
+++ b/lib/random.c
@@ -37,13 +37,41 @@
 # error Unsupported platform
 #endif
 
-static _Thread_local void *gnutls_rnd_ctx;
 
+/* Per thread context of random generator, and a flag to indicate initialization */
+static _Thread_local void *gnutls_rnd_ctx;
 static _Thread_local unsigned rnd_initialized = 0;
 
+struct rnd_ctx_list_st {
+       void *ctx;
+       struct rnd_ctx_list_st *next;
+};
+
+/* A global list of all allocated contexts - to be
+ * used during deinitialization. */
+GNUTLS_STATIC_MUTEX(gnutls_rnd_ctx_list_mutex);
+static struct rnd_ctx_list_st *head = NULL;
+
+static int append(void *ctx)
+{
+       struct rnd_ctx_list_st *e = gnutls_malloc(sizeof(*e));
+
+       if (e == NULL)
+               return gnutls_assert_val(GNUTLS_E_MEMORY_ERROR);
+
+       e->ctx = ctx;
+       e->next = head;
+
+       head = e;
+
+       return 0;
+}
+
 inline static int _gnutls_rnd_init(void)
 {
        if (unlikely(!rnd_initialized)) {
+               int ret;
+
                if (_gnutls_rnd_ops.init == NULL) {
                        rnd_initialized = 1;
                        return 0;
@@ -53,6 +81,16 @@ inline static int _gnutls_rnd_init(void)
                        gnutls_assert();
                        return GNUTLS_E_RANDOM_FAILED;
                }
+
+               GNUTLS_STATIC_MUTEX_LOCK(gnutls_rnd_ctx_list_mutex);
+               ret = append(gnutls_rnd_ctx);
+               GNUTLS_STATIC_MUTEX_UNLOCK(gnutls_rnd_ctx_list_mutex);
+               if (ret < 0) {
+                       gnutls_assert();
+                       _gnutls_rnd_ops.deinit(gnutls_rnd_ctx);
+                       return ret;
+               }
+
                rnd_initialized = 1;
        }
        return 0;
@@ -84,11 +122,19 @@ int _gnutls_rnd_preinit(void)
 
 void _gnutls_rnd_deinit(void)
 {
-       if (rnd_initialized && _gnutls_rnd_ops.deinit != NULL) {
-               _gnutls_rnd_ops.deinit(gnutls_rnd_ctx);
+       if (_gnutls_rnd_ops.deinit != NULL) {
+               struct rnd_ctx_list_st *e = head, *next;
+
+               while(e != NULL) {
+                       next = e->next;
+                       _gnutls_rnd_ops.deinit(e->ctx);
+                       gnutls_free(e);
+                       e = next;
+               }
+               head = NULL;
        }
-       rnd_initialized = 0;
 
+       rnd_initialized = 0;
        _rnd_system_entropy_deinit();
 
        return;