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bsd/dev/random/randomdev.c xnu-12377.101.15 xnu-344.34
--- xnu/xnu-12377.101.15/bsd/dev/random/randomdev.c
+++ xnu/xnu-344.34/bsd/dev/random/randomdev.c
@@ -1,31 +1,24 @@
 /*
- * Copyright (c) 1999-2009 Apple, Inc. All rights reserved.
+ * Copyright (c) 1999, 2000-2002 Apple Computer, 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
+ * @APPLE_LICENSE_HEADER_START@
+ * 
+ * The contents of this file constitute Original Code as defined in and
+ * are subject to the Apple Public Source License Version 1.1 (the
+ * "License").  You may not use this file except in compliance with the
+ * License.  Please obtain a copy of the License at
+ * http://www.apple.com/publicsource and read it before using this file.
+ * 
+ * This 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@
- */
-
+ * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
+ * License for the specific language governing rights and limitations
+ * under the License.
+ * 
+ * @APPLE_LICENSE_HEADER_END@
+ */
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -34,139 +27,164 @@
 #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;
-
-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 */
+	eno_ioctl,			/* ioctl */
+	nulldev,			/* stop */
+	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 */
+
+/*
+ *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,
-	    UID_ROOT, GID_WHEEL, 0666, "random");
+	devfs_make_node(makedev (ret, 0), DEVFS_CHAR,
+		UID_ROOT, GID_WHEEL, 0644, "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");
-}
-
-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;
+	devfs_make_node(makedev (ret, 1), DEVFS_CHAR,
+		UID_ROOT, GID_WHEEL, 0644, "urandom", 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)
-{
+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
 	 */
 	if (flags & FWRITE) {
-		if (securelevel >= 2) {
-			return EPERM;
-		}
-#ifndef __APPLE__
-		if ((securelevel >= 1) && proc_suser(p)) {
-			return EPERM;
-		}
-#endif  /* !__APPLE__ */
+		if (securelevel >= 2)
+			return (EPERM);
+		if ((securelevel >= 1) && suser(p->p_ucred, &p->p_acflag))
+			return (EPERM);
 	}
 
-	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;
+random_close(dev_t dev, int flags, int mode, struct proc *p)
+{
+	return (0);
 }
 
 
@@ -175,85 +193,111 @@
  * 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;
-		}
-		retCode = write_random(rdBuffer, (u_int)bytesToInput);
-		if (retCode != 0) {
-			break;
-		}
-	}
-
-	return retCode;
+random_write (dev_t dev, struct uio *uio, 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->uio_resid > 0 && retCode == 0) {
+        /* get the user's data */
+        int bytesToInput = min(uio->uio_resid, sizeof (rdBuffer));
+        retCode = uiomove(rdBuffer, bytesToInput, uio);
+        if (retCode != 0)
+            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(__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
-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);
-}
+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)
+            goto error_exit;
+    }
+    
+    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);
+    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);
+}
+