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>

1 files changed, 50 insertions, 4 deletions

diff --git a/lib/random.c b/lib/random.c
index 73fb143d7f..2fe82adc7d 100644
--- 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;