Add DEV_RANDOM pseudo-option and use it to "include out" random(4)

if desired.

Retire randomdev_none.c and introduce random_infra.c for resident
infrastructure. Completely stub out random(4) calls in the "without
DEV_RANDOM" case.

Add RANDOM_LOADABLE option to allow loadable Yarrow/Fortuna/LocallyWritten
algorithm.  Add a skeleton "other" algorithm framework for folks
to add their own processing code. NIST, anyone?

Retire the RANDOM_DUMMY option.

Build modules for Yarrow, Fortuna and "other".

Use atomics for the live entropy rate-tracking.

Convert ints to bools for the 'seeded' logic.

Move _write() function from the algorithm-specific areas to randomdev.c

Get rid of reseed() function - it is unused.

Tidy up the opt_*.h includes.

Update documentation for random(4) modules.

Fix test program (reviewers, please leave this).

Differential Revision:    https://reviews.freebsd.org/D3354
Reviewed by:              wblock,delphij,jmg,bjk
Approved by:              so (/dev/random blanket)

1 files changed, 62 insertions, 0 deletions

diff --git a/sys/dev/random/other_algorithm.h b/sys/dev/random/other_algorithm.h
new file mode 100644
index 0000000..8ca2bb8
--- /dev/null
+++ b/sys/dev/random/other_algorithm.h
@@ -0,0 +1,62 @@
+/*-
+ * Copyright (c) 2015 Mark R V Murray
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer
+ *    in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+/*-
+ * This is a skeleton for folks who wish to build a loadable module
+ * containing an alternative entropy-processing algorithm for random(4).
+ *
+ * The functions below should be completed with the appropriate code,
+ * and the nearby yarrow.c and fortuna.c may be consulted for examples
+ * of working code.
+ *
+ * The author is willing to provide reasonable help to those wishing to
+ * write such a module for themselves. Please use the markm@ FreeBSD
+ * email address, and ensure that you are developing this on a suitably
+ * supported branch (This is currently 11-CURRENT, and will be no
+ * older than 11-STABLE in the future).
+ */
+
+#ifndef SYS_DEV_RANDOM_OTHER_H_INCLUDED
+#define	SYS_DEV_RANDOM_OTHER_H_INCLUDED
+
+#ifdef _KERNEL
+typedef struct mtx mtx_t;
+#define	RANDOM_RESEED_INIT_LOCK(x)		mtx_init(&other_mtx, "reseed mutex", NULL, MTX_DEF)
+#define	RANDOM_RESEED_DEINIT_LOCK(x)		mtx_destroy(&other_mtx)
+#define	RANDOM_RESEED_LOCK(x)			mtx_lock(&other_mtx)
+#define	RANDOM_RESEED_UNLOCK(x)			mtx_unlock(&other_mtx)
+#define	RANDOM_RESEED_ASSERT_LOCK_OWNED(x)	mtx_assert(&other_mtx, MA_OWNED)
+#else
+#define	RANDOM_RESEED_INIT_LOCK(x)		mtx_init(&other_mtx, mtx_plain)
+#define	RANDOM_RESEED_DEINIT_LOCK(x)		mtx_destroy(&other_mtx)
+#define	RANDOM_RESEED_LOCK(x)			mtx_lock(&other_mtx)
+#define	RANDOM_RESEED_UNLOCK(x)			mtx_unlock(&other_mtx)
+#define	RANDOM_RESEED_ASSERT_LOCK_OWNED(x)
+#endif
+
+#endif /* SYS_DEV_RANDOM_OTHER_H_INCLUDED */