pg_strong_random-v2.patch

diff --git a/src/port/pg_strong_random.c b/src/port/pg_strong_random.c
new file mode 100644
index bc7a8aa..a2ab8c1
--- a/src/port/pg_strong_random.c
+++ b/src/port/pg_strong_random.c
@@ -103,6 +103,37 @@ pg_strong_random(void *buf, size_t len)
 	 * When built with OpenSSL, use OpenSSL's RAND_bytes function.
 	 */
 #if defined(USE_OPENSSL_RANDOM)
+	/*
+	 * Check that OpenSSL's CSPRNG has been sufficiently seeded, and if not
+	 * add more seed data using RAND_poll().  With some older versions of
+	 * OpenSSL, it may be necessary to call RAND_poll() a number of times.
+	 */
+#define NUM_RAND_POLL_RETRIES 8
+
+	if (RAND_status() == 0)
+	{
+		int			i;
+
+		for (i = 0; i < NUM_RAND_POLL_RETRIES; i++)
+		{
+			if (RAND_poll() == 0)
+			{
+				/*
+				 * RAND_poll() failed to generate any seed data, which means
+				 * that RAND_bytes() will probably fail.  For now, just fall
+				 * through and let that happen.  XXX: maybe we could seed it
+				 * some other way.
+				 */
+				break;
+			}
+
+			if (RAND_status() == 1)
+			{
+				/* The CSPRNG is now sufficiently seeded */
+				break;
+			}
+		}
+	}
 	if (RAND_bytes(buf, len) == 1)
 		return true;
 	return false;