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--- xnu/xnu-4903.231.4/bsd/dev/random/randomdev.c
+++ xnu/xnu-517/bsd/dev/random/randomdev.c
@@ -1,20 +1,17 @@
/*
- * Copyright (c) 1999-2009 Apple, Inc. All rights reserved.
+ * Copyright (c) 1999, 2000-2003 Apple Computer, Inc. All rights reserved.
*
- * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
- *
+ * @APPLE_LICENSE_HEADER_START@
+ *
+ * Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
+ *
* 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.
- *
+ * compliance with the License. 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,
@@ -22,10 +19,9 @@
* 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@
- */
-
+ *
+ * @APPLE_LICENSE_HEADER_END@
+ */
#include <sys/param.h>
#include <sys/systm.h>
@@ -34,25 +30,15 @@
#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 <kern/lock.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>
+#include <dev/random/YarrowCoreLib/include/yarrow.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;
@@ -66,9 +52,9 @@
random_close, /* close */
random_read, /* read */
random_write, /* write */
- random_ioctl, /* ioctl */
- (stop_fcn_t *)nulldev, /* stop */
- (reset_fcn_t *)nulldev, /* reset */
+ random_ioctl, /* ioctl */
+ nulldev, /* stop */
+ nulldev, /* reset */
NULL, /* tty's */
eno_select, /* select */
eno_mmap, /* mmap */
@@ -78,36 +64,103 @@
0 /* type */
};
+/* Used to detect whether we've already been initialized */
+static int gRandomInstalled = 0;
+static PrngRef gPrngRef;
+static int gRandomError = 1;
+static mutex_t *gYarrowMutex = 0;
+
+#define RESEED_TICKS 50 /* how long a reseed operation can take */
+
+/*
+ *Initialize ONLY the Yarrow generator.
+ */
+void PreliminarySetup ()
+{
+ prng_error_status perr;
+ struct timeval tt;
+ char buffer [16];
+
+ /* create a Yarrow object */
+ perr = prngInitialize(&gPrngRef);
+ if (perr != 0) {
+ printf ("Couldn't initialize Yarrow, /dev/random will not work.\n");
+ return;
+ }
+
+ /* clear the error flag, reads and write should then work */
+ gRandomError = 0;
+
+ /* get a little non-deterministic data as an initial seed. */
+ microtime(&tt);
+
+ /*
+ * So how much of the system clock is entropic?
+ * It's hard to say, but assume that at least the
+ * least significant byte of a 64 bit structure
+ * is entropic. It's probably more, how can you figure
+ * the exact time the user turned the computer on, for example.
+ */
+ perr = prngInput(gPrngRef, (BYTE*) &tt, sizeof (tt), SYSTEM_SOURCE, 8);
+ if (perr != 0) {
+ /* an error, complain */
+ printf ("Couldn't seed Yarrow.\n");
+ return;
+ }
+
+ /* turn the data around */
+ perr = prngOutput(gPrngRef, (BYTE*) buffer, sizeof (buffer));
+
+ /* and scramble it some more */
+ perr = prngForceReseed(gPrngRef, RESEED_TICKS);
+
+ /* make a mutex to control access */
+ gYarrowMutex = mutex_alloc(0);
+}
/*
* Called to initialize our device,
* and to register ourselves with devfs
*/
void
-random_init(void)
+random_init()
{
int ret;
+
+ if (gRandomInstalled)
+ return;
+
+ /* install us in the file system */
+ gRandomInstalled = 1;
+
+ /* setup yarrow and the mutex */
+ PreliminarySetup();
ret = cdevsw_add(RANDOM_MAJOR, &random_cdevsw);
if (ret < 0) {
- panic("random_init: failed to allocate a major number!");
+ printf("random_init: failed to allocate a major number!\n");
+ gRandomInstalled = 0;
+ return;
}
- devfs_make_node(makedev (ret, RANDOM_MINOR), DEVFS_CHAR,
+ devfs_make_node(makedev (ret, 0), DEVFS_CHAR,
UID_ROOT, GID_WHEEL, 0666, "random", 0);
/*
- * also make urandom
+ * also make urandom
* (which is exactly the same thing in our context)
*/
- devfs_make_node(makedev (ret, URANDOM_MINOR), DEVFS_CHAR,
+ devfs_make_node(makedev (ret, 1), 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 )
+}
+
+int
+random_ioctl(dev, cmd, data, flag, p)
+ dev_t dev;
+ u_long cmd;
+ caddr_t data;
+ int flag;
+ struct proc *p;
{
switch (cmd) {
case FIONBIO:
@@ -124,10 +177,15 @@
* 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)
-{
+
+int
+random_open(dev_t dev, int flags, int devtype, struct proc *p)
+{
+ if (gRandomError != 0) {
+ /* forget it, yarrow didn't come up */
+ return (ENOTSUP);
+ }
+
/*
* if we are being opened for write,
* make sure that we have privledges do so
@@ -136,7 +194,7 @@
if (securelevel >= 2)
return (EPERM);
#ifndef __APPLE__
- if ((securelevel >= 1) && proc_suser(p))
+ if ((securelevel >= 1) && suser(p->p_ucred, &p->p_acflag))
return (EPERM);
#endif /* !__APPLE__ */
}
@@ -148,9 +206,9 @@
/*
* close the device.
*/
-
-int
-random_close(__unused dev_t dev, __unused int flags, __unused int mode, __unused struct proc *p)
+
+int
+random_close(dev_t dev, int flags, int mode, struct proc *p)
{
return (0);
}
@@ -161,82 +219,111 @@
* prng.
*/
int
-random_write (dev_t dev, struct uio *uio, __unused int ioflag)
+random_write (dev_t dev, struct uio *uio, int ioflag)
{
int retCode = 0;
char rdBuffer[256];
- if (minor(dev) != RANDOM_MINOR)
- return EPERM;
-
+ if (gRandomError != 0) {
+ return (ENOTSUP);
+ }
+
+ /* get control of the Yarrow instance, Yarrow is NOT thread safe */
+ mutex_lock(gYarrowMutex);
+
/* Security server is sending us entropy */
- while (uio_resid(uio) > 0 && retCode == 0) {
+ while (uio->uio_resid > 0 && retCode == 0) {
/* get the user's data */
- int bytesToInput = MIN(uio_resid(uio),
- (user_ssize_t) sizeof(rdBuffer));
+ int bytesToInput = min(uio->uio_resid, sizeof (rdBuffer));
retCode = uiomove(rdBuffer, bytesToInput, uio);
if (retCode != 0)
- break;
- retCode = write_random(rdBuffer, bytesToInput);
+ goto /*ugh*/ error_exit;
+
+ /* put it in Yarrow */
+ if (prngInput(gPrngRef, (BYTE*) rdBuffer,
+ sizeof (rdBuffer), SYSTEM_SOURCE,
+ sizeof (rdBuffer) * 8) != 0) {
+ retCode = EIO;
+ goto error_exit;
+ }
+ }
+
+ /* force a reseed */
+ if (prngForceReseed(gPrngRef, RESEED_TICKS) != 0) {
+ retCode = EIO;
+ goto error_exit;
+ }
+
+ /* retCode should be 0 at this point */
+
+error_exit: /* do this to make sure the mutex unlocks. */
+ mutex_unlock(gYarrowMutex);
+ return (retCode);
+}
+
+/*
+ * return data to the caller. Results unpredictable.
+ */
+int
+random_read(dev_t dev, struct uio *uio, int ioflag)
+{
+ int retCode = 0;
+ char wrBuffer[512];
+
+ if (gRandomError != 0)
+ return (ENOTSUP);
+
+ /* lock down the mutex */
+ mutex_lock(gYarrowMutex);
+
+ while (uio->uio_resid > 0 && retCode == 0) {
+ /* get the user's data */
+ int bytesToRead = min(uio->uio_resid, sizeof (wrBuffer));
+
+ /* get the data from Yarrow */
+ if (prngOutput(gPrngRef, (BYTE *) wrBuffer, sizeof (wrBuffer)) != 0) {
+ printf ("Couldn't read data from Yarrow.\n");
+
+ /* something's really weird */
+ retCode = EIO;
+ goto error_exit;
+ }
+
+ retCode = uiomove(wrBuffer, bytesToRead, uio);
+
if (retCode != 0)
- break;
- }
-
+ goto error_exit;
+ }
+
+ retCode = 0;
+
+error_exit:
+ mutex_unlock(gYarrowMutex);
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;
+/* export good random numbers to the rest of the kernel */
+void
+read_random(void* buffer, u_int numbytes)
+{
+ if (gYarrowMutex == 0) { /* are we initialized? */
+ PreliminarySetup ();
+ }
+
+ mutex_lock(gYarrowMutex);
+ prngOutput(gPrngRef, (BYTE *) buffer, numbytes);
+ mutex_unlock(gYarrowMutex);
+}
+
+/*
+ * Return an unsigned long pseudo-random number.
+ */
+u_long
+RandomULong()
+{
+ u_long 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);
-}