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bsd/dev/random/randomdev.c xnu-4570.41.2 xnu-792.2.4
--- xnu/xnu-4570.41.2/bsd/dev/random/randomdev.c
+++ xnu/xnu-792.2.4/bsd/dev/random/randomdev.c
@@ -1,31 +1,24 @@
 /*
- * Copyright (c) 1999-2009 Apple, Inc. All rights reserved.
+ * Copyright (c) 1999-2004 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>
@@ -34,25 +27,16 @@
 #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;
 
@@ -78,35 +62,99 @@
 	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( 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);
+}
 
 /*
  * Called to initialize our device,
  * and to register ourselves with devfs
  */
 void
-random_init(void)
+random_init( void )
 {
 	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,
+}
+
+int
+random_ioctl(	__unused dev_t dev, u_long cmd, __unused caddr_t data, 
 				__unused int flag, __unused struct proc *p  )
 {
 	switch (cmd) {
@@ -124,10 +172,15 @@
  * 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)
 {
+	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
@@ -148,7 +201,7 @@
 /*
  * close the device.
  */
-
+ 
 int
 random_close(__unused dev_t dev, __unused int flags, __unused int mode, __unused struct proc *p)
 {
@@ -161,82 +214,113 @@
  * prng.
  */
 int
-random_write (dev_t dev, struct uio *uio, __unused int ioflag)
+random_write (__unused dev_t dev, struct uio *uio, __unused 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) {
         /* get the user's data */
-        int bytesToInput = MIN(uio_resid(uio),
-			       (user_ssize_t) sizeof(rdBuffer));
+        // 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)
-	    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(__unused dev_t dev, struct uio *uio, __unused int ioflag)
+{
+    int retCode = 0;
+    char wrBuffer[512];
+
+    if (gRandomError != 0)
+        return (ENOTSUP);
+
+   /* lock down the mutex */
+    mutex_lock(gYarrowMutex);
+
+    while (uio_resid(uio) > 0 && retCode == 0) {
+        /* get the user's data */
+        // LP64todo - fix this!  uio_resid may be 64-bit value
+        int bytesToRead = min(uio_resid(uio), 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( void )
+{
+	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);
-}