1 files changed, 101 insertions, 0 deletions
diff --git a/sys/contrib/openzfs/lib/libspl/random.c b/sys/contrib/openzfs/lib/libspl/random.c
new file mode 100644
index 000000000000..c6f0ee7ae0f7
--- /dev/null
+++ b/sys/contrib/openzfs/lib/libspl/random.c
@@ -0,0 +1,101 @@
+// SPDX-License-Identifier: CDDL-1.0
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or https://opensource.org/licenses/CDDL-1.0.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+/*
+ * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2018 by Delphix. All rights reserved.
+ * Copyright (c) 2016 Actifio, Inc. All rights reserved.
+ * Copyright (c) 2025, Klara, Inc.
+ */
+
+#include <stdint.h>
+#include <fcntl.h>
+#include <assert.h>
+#include <sys/random.h>
+#include "libspl_impl.h"
+
+#define	RANDOM_PATH	"/dev/random"
+#define	URANDOM_PATH	"/dev/urandom"
+
+static int random_fd = -1, urandom_fd = -1;
+
+static boolean_t force_pseudo = B_FALSE;
+
+void
+random_init(void)
+{
+	/* Handle multiple calls. */
+	if (random_fd != -1) {
+		ASSERT3U(urandom_fd, !=, -1);
+		return;
+	}
+
+	VERIFY((random_fd = open(RANDOM_PATH, O_RDONLY | O_CLOEXEC)) != -1);
+	VERIFY((urandom_fd = open(URANDOM_PATH, O_RDONLY | O_CLOEXEC)) != -1);
+}
+
+void
+random_fini(void)
+{
+	close(random_fd);
+	close(urandom_fd);
+
+	random_fd = -1;
+	urandom_fd = -1;
+}
+
+void
+random_force_pseudo(boolean_t onoff)
+{
+	force_pseudo = onoff;
+}
+
+static int
+random_get_bytes_common(uint8_t *ptr, size_t len, int fd)
+{
+	size_t resid = len;
+	ssize_t bytes;
+
+	ASSERT(fd != -1);
+
+	while (resid != 0) {
+		bytes = read(fd, ptr, resid);
+		ASSERT3S(bytes, >=, 0);
+		ptr += bytes;
+		resid -= bytes;
+	}
+
+	return (0);
+}
+
+int
+random_get_bytes(uint8_t *ptr, size_t len)
+{
+	if (force_pseudo)
+		return (random_get_pseudo_bytes(ptr, len));
+	return (random_get_bytes_common(ptr, len, random_fd));
+}
+
+int
+random_get_pseudo_bytes(uint8_t *ptr, size_t len)
+{
+	return (random_get_bytes_common(ptr, len, urandom_fd));
+}