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--- xnu/xnu-12377.101.15/bsd/dev/random/randomdev.c
+++ xnu/xnu-792.13.8/bsd/dev/random/randomdev.c
@@ -1,31 +1,32 @@
/*
- * Copyright (c) 1999-2009 Apple, Inc. All rights reserved.
+ * Copyright (c)1999-2004 Apple Computer, Inc. All rights reserved.
*
- * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ * @APPLE_LICENSE_OSREFERENCE_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.
*
- * 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.
*
- * 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
+ * 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@
- */
-
+ * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
+ */
#include <sys/param.h>
#include <sys/systm.h>
@@ -36,61 +37,185 @@
#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>
+#include <crypto/sha1.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;
-static int
-random_stop(__unused struct tty *tp, __unused int rw)
-{
- return 0;
-}
-
-static int
-random_reset(__unused int uban)
-{
- return 0;
-}
-
-static int
-random_select(__unused dev_t dev, __unused int which, __unused void *wql,
- __unused struct proc *p)
-{
- return ENODEV;
-}
-
-static const struct cdevsw random_cdevsw =
-{
- .d_open = random_open,
- .d_close = random_close,
- .d_read = random_read,
- .d_write = random_write,
- .d_ioctl = random_ioctl,
- .d_stop = random_stop,
- .d_reset = random_reset,
- .d_select = random_select,
- .d_mmap = eno_mmap,
- .d_strategy = eno_strat,
- .d_reserved_1 = eno_getc,
- .d_reserved_2 = eno_putc,
+/*
+ * 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 */
};
+/* 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 */
+
+
+enum {kBSizeInBits = 160}; // MUST be a multiple of 32!!!
+enum {kBSizeInBytes = kBSizeInBits / 8};
+typedef u_int32_t BlockWord;
+enum {kWordSizeInBits = 32};
+enum {kBSize = 5};
+typedef BlockWord Block[kBSize];
+
+/* define prototypes to keep the compiler happy... */
+
+void add_blocks(Block a, Block b, BlockWord carry);
+void fips_initialize(void);
+void random_block(Block b);
+
+/*
+ * Get 120 bits from yarrow
+ */
+
+/*
+ * add block b to block a
+ */
+void
+add_blocks(Block a, Block b, BlockWord carry)
+{
+ int i = kBSize;
+ while (--i >= 0)
+ {
+ u_int64_t c = (u_int64_t)carry +
+ (u_int64_t)a[i] +
+ (u_int64_t)b[i];
+ a[i] = c & ((1LL << kWordSizeInBits) - 1);
+ carry = c >> kWordSizeInBits;
+ }
+}
+
+
+
+struct sha1_ctxt g_sha1_ctx;
+char zeros[(512 - kBSizeInBits) / 8];
+Block g_xkey;
+Block g_random_data;
+int g_bytes_used;
+
+/*
+ * Setup for fips compliance
+ */
+
+/*
+ * get a random block of data per fips 186-2
+ */
+void
+random_block(Block b)
+{
+ // do one iteration
+ Block xSeed;
+ prngOutput (gPrngRef, (BYTE*) &xSeed, sizeof (xSeed));
+
+ // add the seed to the previous value of g_xkey
+ add_blocks (g_xkey, xSeed, 0);
+
+ // compute "G"
+ SHA1Update (&g_sha1_ctx, (const u_int8_t *) &g_xkey, sizeof (g_xkey));
+
+ // add zeros to fill the internal SHA-1 buffer
+ SHA1Update (&g_sha1_ctx, (const u_int8_t *)zeros, sizeof (zeros));
+
+ // write the resulting block
+ memmove(b, g_sha1_ctx.h.b8, sizeof (Block));
+
+ // fix up the next value of g_xkey
+ add_blocks (g_xkey, b, 1);
+}
+
+/*
+ *Initialize ONLY the Yarrow generator.
+ */
+void
+PreliminarySetup(void)
+{
+ 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);
+
+ fips_initialize ();
+}
+
+void
+fips_initialize(void)
+{
+ /* Read the initial value of g_xkey from yarrow */
+ prngOutput (gPrngRef, (BYTE*) &g_xkey, sizeof (g_xkey));
+
+ /* initialize our SHA1 generator */
+ SHA1Init (&g_sha1_ctx);
+
+ /* other initializations */
+ memset (zeros, 0, sizeof (zeros));
+ g_bytes_used = 0;
+ random_block(g_random_data);
+}
/*
* Called to initialize our device,
@@ -101,25 +226,36 @@
{
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,
- UID_ROOT, GID_WHEEL, 0666, "random");
+ 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,
- UID_ROOT, GID_WHEEL, 0666, "urandom");
+ 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 )
+random_ioctl( __unused dev_t dev, u_long cmd, __unused caddr_t data,
+ __unused int flag, __unused struct proc *p )
{
switch (cmd) {
case FIONBIO:
@@ -129,44 +265,47 @@
return ENODEV;
}
- return 0;
+ 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 (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
*/
if (flags & FWRITE) {
- if (securelevel >= 2) {
- return EPERM;
- }
+ if (securelevel >= 2)
+ return (EPERM);
#ifndef __APPLE__
- if ((securelevel >= 1) && proc_suser(p)) {
- return EPERM;
- }
-#endif /* !__APPLE__ */
+ if ((securelevel >= 1) && proc_suser(p))
+ return (EPERM);
+#endif /* !__APPLE__ */
}
- return 0;
+ return (0);
}
/*
* close the device.
*/
-
+
int
random_close(__unused dev_t dev, __unused int flags, __unused int mode, __unused struct proc *p)
{
- return 0;
+ return (0);
}
@@ -175,85 +314,131 @@
* 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 ((size_t)uio_resid(uio) > 0 && retCode == 0) {
- /* get the user's data */
- size_t bytesToInput = MIN((size_t)uio_resid(uio), sizeof(rdBuffer));
- retCode = uiomove(rdBuffer, (int)bytesToInput, uio);
- if (retCode != 0) {
- break;
+random_write (__unused dev_t dev, struct uio *uio, __unused int ioflag)
+{
+ int retCode = 0;
+ char rdBuffer[256];
+
+ 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) {
+ /* get the user's data */
+ // LP64todo - fix this! uio_resid may be 64-bit value
+ int bytesToInput = min(uio_resid(uio), sizeof (rdBuffer));
+ retCode = uiomove(rdBuffer, bytesToInput, uio);
+ if (retCode != 0)
+ goto /*ugh*/ error_exit;
+
+ /* put it in Yarrow */
+ if (prngInput(gPrngRef, (BYTE*)rdBuffer,
+ bytesToInput, SYSTEM_SOURCE,
+ bytesToInput * 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(__unused dev_t dev, struct uio *uio, __unused int ioflag)
+{
+ int retCode = 0;
+
+ if (gRandomError != 0)
+ return (ENOTSUP);
+
+ /* lock down the mutex */
+ mutex_lock(gYarrowMutex);
+
+ int bytes_remaining = uio_resid(uio);
+ while (bytes_remaining > 0 && retCode == 0) {
+ /* get the user's data */
+ int bytes_to_read = 0;
+
+ int bytes_available = kBSizeInBytes - g_bytes_used;
+ if (bytes_available == 0)
+ {
+ random_block(g_random_data);
+ g_bytes_used = 0;
+ bytes_available = kBSizeInBytes;
}
- retCode = write_random(rdBuffer, (u_int)bytesToInput);
- if (retCode != 0) {
- break;
+
+ bytes_to_read = min (bytes_remaining, bytes_available);
+
+ retCode = uiomove(((u_int8_t*)g_random_data)+ g_bytes_used, bytes_to_read, uio);
+ g_bytes_used += bytes_to_read;
+
+ if (retCode != 0)
+ goto error_exit;
+
+ bytes_remaining = uio_resid(uio);
+ }
+
+ retCode = 0;
+
+error_exit:
+ mutex_unlock(gYarrowMutex);
+ return retCode;
+}
+
+/* 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);
+
+ int bytes_remaining = numbytes;
+ while (bytes_remaining > 0) {
+ int bytes_to_read = min(bytes_remaining, kBSizeInBytes - g_bytes_used);
+ if (bytes_to_read == 0)
+ {
+ random_block(g_random_data);
+ g_bytes_used = 0;
+ bytes_to_read = min(bytes_remaining, kBSizeInBytes);
}
- }
-
- 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];
-
- size_t bytes_remaining = (size_t)uio_resid(uio);
- while (bytes_remaining > 0 && retCode == 0) {
- size_t bytesToRead = MIN(bytes_remaining, sizeof(buffer));
- read_random(buffer, (u_int)bytesToRead);
-
- retCode = uiomove(buffer, (int)bytesToRead, uio);
- if (retCode != 0) {
- break;
- }
-
- bytes_remaining = (size_t)uio_resid(uio);
- }
-
- return retCode;
-}
-
-/*
- * Return an u_int32_t pseudo-random number.
- */
-u_int32_t
+
+ memmove (buffer, ((u_int8_t*)g_random_data)+ g_bytes_used, bytes_to_read);
+ g_bytes_used += bytes_to_read;
+
+ bytes_remaining -= bytes_to_read;
+ }
+
+ mutex_unlock(gYarrowMutex);
+}
+
+/*
+ * Return an unsigned long pseudo-random number.
+ */
+u_long
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;
- user_size_t user_size;
- char buffer[256];
-
- user_addr = (user_addr_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, (u_int)user_size);
- return copyout(buffer, user_addr, user_size);
-}
+ u_long buf;
+ read_random(&buf, sizeof (buf));
+ return (buf);
+}
+