--- /dev/null
+++ xnu/xnu-3789.21.4/bsd/dev/random/randomdev.c
@@ -0,0 +1,242 @@
+/*
+ * Copyright (c) 1999-2009 Apple, Inc. All rights reserved.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
+ */
+
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/proc.h>
+#include <sys/errno.h>
+#include <sys/ioctl.h>
+#include <sys/conf.h>
+#include <sys/fcntl.h>
+#include <string.h>
+#include <miscfs/devfs/devfs.h>
+#include <kern/locks.h>
+#include <kern/clock.h>
+#include <sys/time.h>
+#include <sys/malloc.h>
+#include <sys/sysproto.h>
+#include <sys/uio_internal.h>
+
+#include <dev/random/randomdev.h>
+
+#include <libkern/OSByteOrder.h>
+#include <libkern/OSAtomic.h>
+
+#include <mach/mach_time.h>
+
+#define RANDOM_MAJOR  -1 /* let the kernel pick the device number */
+#define RANDOM_MINOR   0
+#define URANDOM_MINOR  1
+
+d_ioctl_t       random_ioctl;
+
+/*
+ * A struct describing which functions will get invoked for certain
+ * actions.
+ */
+static struct cdevsw random_cdevsw =
+{
+	random_open,		/* open */
+	random_close,		/* close */
+	random_read,		/* read */
+	random_write,		/* write */
+	random_ioctl,		/* ioctl */
+	(stop_fcn_t *)nulldev, /* stop */
+	(reset_fcn_t *)nulldev, /* reset */
+	NULL,				/* tty's */
+	eno_select,			/* select */
+	eno_mmap,			/* mmap */
+	eno_strat,			/* strategy */
+	eno_getc,			/* getc */
+	eno_putc,			/* putc */
+	0					/* type */
+};
+
+
+/*
+ * Called to initialize our device,
+ * and to register ourselves with devfs
+ */
+void
+random_init(void)
+{
+	int ret;
+
+	ret = cdevsw_add(RANDOM_MAJOR, &random_cdevsw);
+	if (ret < 0) {
+		panic("random_init: failed to allocate a major number!");
+	}
+
+	devfs_make_node(makedev (ret, RANDOM_MINOR), DEVFS_CHAR,
+		UID_ROOT, GID_WHEEL, 0666, "random", 0);
+
+	/*
+	 * also make urandom
+	 * (which is exactly the same thing in our context)
+	 */
+	devfs_make_node(makedev (ret, URANDOM_MINOR), DEVFS_CHAR,
+		UID_ROOT, GID_WHEEL, 0666, "urandom", 0);
+
+}
+
+int
+random_ioctl(	__unused dev_t dev, u_long cmd, __unused caddr_t data,
+				__unused int flag, __unused struct proc *p  )
+{
+	switch (cmd) {
+	case FIONBIO:
+	case FIOASYNC:
+		break;
+	default:
+		return ENODEV;
+	}
+
+	return (0);
+}
+
+/*
+ * Open the device.  Make sure init happened, and make sure the caller is
+ * authorized.
+ */
+
+int
+random_open(__unused dev_t dev, int flags, __unused int devtype, __unused struct proc *p)
+{
+	/*
+	 * if we are being opened for write,
+	 * make sure that we have privledges do so
+	 */
+	if (flags & FWRITE) {
+		if (securelevel >= 2)
+			return (EPERM);
+#ifndef __APPLE__
+		if ((securelevel >= 1) && proc_suser(p))
+			return (EPERM);
+#endif	/* !__APPLE__ */
+	}
+
+	return (0);
+}
+
+
+/*
+ * close the device.
+ */
+
+int
+random_close(__unused dev_t dev, __unused int flags, __unused int mode, __unused struct proc *p)
+{
+	return (0);
+}
+
+
+/*
+ * Get entropic data from the Security Server, and use it to reseed the
+ * prng.
+ */
+int
+random_write (dev_t dev, struct uio *uio, __unused int ioflag)
+{
+    int retCode = 0;
+    char rdBuffer[256];
+
+    if (minor(dev) != RANDOM_MINOR)
+	return EPERM;
+
+    /* Security server is sending us entropy */
+
+    while (uio_resid(uio) > 0 && retCode == 0) {
+        /* get the user's data */
+        int bytesToInput = MIN(uio_resid(uio),
+			       (user_ssize_t) sizeof(rdBuffer));
+        retCode = uiomove(rdBuffer, bytesToInput, uio);
+        if (retCode != 0)
+	    break;
+	retCode = write_random(rdBuffer, bytesToInput);
+        if (retCode != 0)
+	    break;
+    }
+
+    return retCode;
+}
+
+/*
+ * return data to the caller.  Results unpredictable.
+ */
+int
+random_read(__unused dev_t dev, struct uio *uio, __unused int ioflag)
+{
+	int retCode = 0;
+	char buffer[512];
+
+	user_ssize_t bytes_remaining = uio_resid(uio);
+	while (bytes_remaining > 0 && retCode == 0) {
+		int bytesToRead = MIN(bytes_remaining,
+				      (user_ssize_t) sizeof(buffer));
+		read_random(buffer, bytesToRead);
+
+		retCode = uiomove(buffer, bytesToRead, uio);
+		if (retCode != 0)
+			break;
+
+		bytes_remaining = uio_resid(uio);
+	}
+
+	return retCode;
+}
+
+/*
+ * Return an u_int32_t pseudo-random number.
+ */
+u_int32_t
+RandomULong(void)
+{
+	u_int32_t buf;
+	read_random(&buf, sizeof (buf));
+	return (buf);
+}
+
+
+int
+getentropy(__unused struct proc * p, struct getentropy_args *gap, __unused int * ret) {
+	user_addr_t user_addr;
+	uint32_t user_size;
+	char buffer[256];
+
+	user_addr = (vm_map_offset_t)gap->buffer;
+	user_size = gap->size;
+	/* Can't request more than 256 random bytes
+	 * at once. Complying with openbsd getentropy()
+	 */
+	if (user_size > sizeof(buffer)) {
+		return EINVAL;
+	}
+	read_random(buffer, user_size);
+	return copyout(buffer, user_addr, user_size);
+}