Decouple yarrow from random(4) device.

* Make Yarrow an optional kernel component -- enabled by "YARROW_RNG" option.
  The files sha2.c, hash.c, randomdev_soft.c and yarrow.c comprise yarrow.

* random(4) device doesn't really depend on rijndael-*.  Yarrow, however, does.

* Add random_adaptors.[ch] which is basically a store of random_adaptor's.
  random_adaptor is basically an adapter that plugs in to random(4).
  random_adaptor can only be plugged in to random(4) very early in bootup.
  Unplugging random_adaptor from random(4) is not supported, and is probably a
  bad idea anyway, due to potential loss of entropy pools.
  We currently have 3 random_adaptors:
  + yarrow
  + rdrand (ivy.c)
  + nehemeiah

* Remove platform dependent logic from probe.c, and move it into
  corresponding registration routines of each random_adaptor provider.
  probe.c doesn't do anything other than picking a specific random_adaptor
  from a list of registered ones.

* If the kernel doesn't have any random_adaptor adapters present then the
  creation of /dev/random is postponed until next random_adaptor is kldload'ed.

* Fix randomdev_soft.c to refer to its own random_adaptor, instead of a
  system wide one.

Submitted by: arthurmesh@gmail.com, obrien
Obtained from: Juniper Networks
Reviewed by: obrien

5 files changed, 246 insertions, 0 deletions

diff --git a/sys/dev/random/random_adaptors.c b/sys/dev/random/random_adaptors.c
new file mode 100644
index 0000000..b10efb3
--- /dev/null
+++ b/sys/dev/random/random_adaptors.c
@@ -0,0 +1,141 @@
+/*-
+ * Copyright (c) 2013 Arthur Mesh <arthurmesh@gmail.com>
+ * 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.
+ *
+ * $FreeBSD$
+ */
+
+#include <sys/param.h>
+#include <sys/kernel.h>
+#include <sys/systm.h>
+#include <sys/lock.h>
+#include <sys/selinfo.h>
+#include <sys/sysctl.h>
+#include <sys/sx.h>
+#include <sys/malloc.h>
+#include <sys/queue.h>
+#include <sys/libkern.h>
+
+#include <dev/random/random_adaptors.h>
+#include <dev/random/randomdev.h>
+
+LIST_HEAD(adaptors_head, random_adaptors);
+static struct adaptors_head adaptors = LIST_HEAD_INITIALIZER(adaptors);
+static struct sx adaptors_lock; /* need a sleepable lock */
+
+/* List for the dynamic sysctls */
+static struct sysctl_ctx_list random_clist;
+
+MALLOC_DEFINE(M_RANDOM_ADAPTORS, "random_adaptors", "Random adaptors buffers");
+
+int
+random_adaptor_register(const char *name, struct random_adaptor *rsp)
+{
+	struct random_adaptors *rpp;
+
+	KASSERT(name != NULL && rsp != NULL, ("invalid input to %s", __func__));
+
+	rpp = malloc(sizeof(struct random_adaptors), M_RANDOM_ADAPTORS, M_WAITOK);
+	rpp->name = name;
+	rpp->rsp = rsp;
+
+	sx_xlock(&adaptors_lock);
+	LIST_INSERT_HEAD(&adaptors, rpp, entries);
+	sx_xunlock(&adaptors_lock);
+
+	return (0);
+}
+
+struct random_adaptor *
+random_adaptor_get(const char *name)
+{
+	struct random_adaptors	*rpp;
+	struct random_adaptor	*rsp;
+
+	rsp = NULL;
+
+	sx_slock(&adaptors_lock);
+
+	LIST_FOREACH(rpp, &adaptors, entries)
+		if (strcmp(rpp->name, name) == 0)
+			rsp = rpp->rsp;
+
+	sx_sunlock(&adaptors_lock);
+
+	return (rsp);
+}
+
+static void
+random_adaptors_deinit(void *unused)
+{
+
+	sx_destroy(&adaptors_lock);
+	sysctl_ctx_free(&random_clist);
+}
+
+#define	NO_ADAPTORS	"<no loaded adaptors>"
+static int
+random_sysctl_adaptors_handler(SYSCTL_HANDLER_ARGS)
+{
+	struct random_adaptors	*rpp;
+	int error;
+
+	error = 0;
+
+	sx_slock(&adaptors_lock);
+
+	if (LIST_EMPTY(&adaptors))
+		error = SYSCTL_OUT(req, NO_ADAPTORS, strlen(NO_ADAPTORS));
+
+	LIST_FOREACH(rpp, &adaptors, entries) {
+		error = SYSCTL_OUT(req, " ", 1);
+		if (!error)
+			error = SYSCTL_OUT(req, rpp->name, strlen(rpp->name));
+		if (error)
+			break;
+	}
+
+	sx_sunlock(&adaptors_lock);
+
+	return (error);
+}
+
+static void
+random_adaptors_init(void *unused)
+{
+
+	SYSCTL_PROC(_kern_random, OID_AUTO, adaptors,
+	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
+	    NULL, 0, random_sysctl_adaptors_handler, "",
+	    "Random Number Generator adaptors");
+
+	sx_init(&adaptors_lock, "random_adaptors");
+}
+
+SYSCTL_NODE(_kern, OID_AUTO, random, CTLFLAG_RW, 0, "Random Number Generator");
+
+SYSINIT(random_adaptors, SI_SUB_DRIVERS, SI_ORDER_FIRST, random_adaptors_init,
+    NULL);
+SYSUNINIT(random_adaptors, SI_SUB_DRIVERS, SI_ORDER_FIRST,
+    random_adaptors_deinit, NULL);
diff --git a/sys/dev/random/random_adaptors.h b/sys/dev/random/random_adaptors.h
new file mode 100644
index 0000000..6c106df
--- /dev/null
+++ b/sys/dev/random/random_adaptors.h
@@ -0,0 +1,66 @@
+/*-
+ * Copyright (c) 2013 Arthur Mesh <arthurmesh@gmail.com>
+ * 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.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef __RANDOM_ADAPTORS_H__
+#define __RANDOM_ADAPTORS_H__
+
+#include <sys/eventhandler.h>
+
+struct random_adaptors {
+	LIST_ENTRY(random_adaptors) entries;	/* list of providesr */
+	const char		*name;		/* name of random adaptor */
+	struct random_adaptor	*rsp;
+};
+
+struct random_adaptor *random_adaptor_get(const char *);
+int random_adaptor_register(const char *, struct random_adaptor *);
+
+/*
+ * random_adaptor's should be registered prior to
+ * random module (SI_SUB_DRIVERS/SI_ORDER_MIDDLE)
+ */
+#define RANDOM_ADAPTOR_MODULE(name, modevent, ver)		\
+    static moduledata_t name##_mod = {				\
+	#name,							\
+	modevent,						\
+	0							\
+    };								\
+    DECLARE_MODULE(name, name##_mod, SI_SUB_DRIVERS,		\
+		   SI_ORDER_SECOND);				\
+    MODULE_VERSION(name, ver);					\
+    MODULE_DEPEND(name, random, 1, 1, 1);
+
+typedef void (*random_adaptor_attach_hook)(void *, struct random_adaptor *);
+EVENTHANDLER_DECLARE(random_adaptor_attach, random_adaptor_attach_hook);
+
+/* kern.random sysctls */
+#ifdef SYSCTL_DECL	/* from sysctl.h */
+SYSCTL_DECL(_kern_random);
+#endif /* SYSCTL_DECL */
+
+#endif /* __RANDOM_ADAPTORS_H__ */
diff --git a/sys/modules/padlock_rng/Makefile b/sys/modules/padlock_rng/Makefile
new file mode 100644
index 0000000..5c96c20
--- /dev/null
+++ b/sys/modules/padlock_rng/Makefile
@@ -0,0 +1,10 @@
+# $FreeBSD$
+
+.PATH: ${.CURDIR}/../../dev/random
+
+KMOD=	padlock_rng
+
+SRCS+=	\
+	nehemiah.c
+
+.include <bsd.kmod.mk>
diff --git a/sys/modules/rdrand_rng/Makefile b/sys/modules/rdrand_rng/Makefile
new file mode 100644
index 0000000..2cfd3fd
--- /dev/null
+++ b/sys/modules/rdrand_rng/Makefile
@@ -0,0 +1,10 @@
+# $FreeBSD$
+
+.PATH: ${.CURDIR}/../../dev/random
+
+KMOD=	rdrand_rng
+
+SRCS+=	\
+	ivy.c
+
+.include <bsd.kmod.mk>
diff --git a/sys/modules/yarrow_rng/Makefile b/sys/modules/yarrow_rng/Makefile
new file mode 100644
index 0000000..0974cba
--- /dev/null
+++ b/sys/modules/yarrow_rng/Makefile
@@ -0,0 +1,19 @@
+# $FreeBSD$
+
+.PATH: ${.CURDIR}/../../dev/random
+.PATH: ${.CURDIR}/../../crypto/rijndael
+
+KMOD=	yarrow_rng
+
+SRCS+=	\
+	hash.c \
+	randomdev_soft.c \
+	rijndael-alg-fst.c \
+	rijndael-api-fst.c \
+	yarrow.c
+
+SRCS+=	bus_if.h device_if.h
+
+CFLAGS+= -I${.CURDIR}/../..
+
+.include <bsd.kmod.mk>