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bsd/dev/random/randomdev.c xnu-1228 xnu-792.24.17
--- xnu/xnu-1228/bsd/dev/random/randomdev.c
+++ xnu/xnu-792.24.17/bsd/dev/random/randomdev.c
@@ -1,29 +1,23 @@
 /*
- * Copyright (c) 1999-2006 Apple Computer, Inc. All rights reserved.
+ * Copyright (c)1999-2004 Apple Computer, Inc. All rights reserved.
  *
- * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ * @APPLE_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.
+ * 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.
  * 
- * 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
+ * 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.
+ * FITNESS FOR A PARTICULAR PURPOSE 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>
@@ -36,17 +30,13 @@
 #include <string.h>
 #include <miscfs/devfs/devfs.h>
 #include <kern/lock.h>
-#include <kern/clock.h>
 #include <sys/time.h>
 #include <sys/malloc.h>
 #include <sys/uio_internal.h>
 
 #include <dev/random/randomdev.h>
 #include <dev/random/YarrowCoreLib/include/yarrow.h>
-#include <libkern/crypto/sha1.h>
-
-#include <mach/mach_time.h>
-#include <machine/machine_routines.h>
+#include <crypto/sha1.h>
 
 #define RANDOM_MAJOR  -1 /* let the kernel pick the device number */
 
@@ -78,12 +68,7 @@
 static int gRandomInstalled = 0;
 static PrngRef gPrngRef;
 static int gRandomError = 1;
-static lck_grp_t *gYarrowGrp;
-static lck_attr_t *gYarrowAttr;
-static lck_grp_attr_t *gYarrowGrpAttr;
-static lck_mtx_t *gYarrowMutex = 0;
-
-void CheckReseed(void);
+static mutex_t *gYarrowMutex = 0;
 
 #define RESEED_TICKS 50 /* how long a reseed operation can take */
 
@@ -99,7 +84,7 @@
 
 void add_blocks(Block a, Block b, BlockWord carry);
 void fips_initialize(void);
-void random_block(Block b);
+void random_block(Block b, int addOptional);
 u_int32_t CalculateCRC(u_int8_t* buffer, size_t length);
 
 /*
@@ -194,18 +179,21 @@
  * get a random block of data per fips 186-2
  */
 void
-random_block(Block b)
+random_block(Block b, int addOptional)
 {
 	int repeatCount = 0;
 	do
 	{
-		// 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);
-
+		if (addOptional)
+		{
+			// 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));
 		
@@ -261,6 +249,8 @@
 PreliminarySetup(void)
 {
     prng_error_status perr;
+    struct timeval tt;
+    char buffer [16];
 
     /* create a Yarrow object */
     perr = prngInitialize(&gPrngRef);
@@ -271,10 +261,6 @@
 
 	/* clear the error flag, reads and write should then work */
     gRandomError = 0;
-
-   {
-    struct timeval tt;
-    char buffer [16];
 
     /* get a little non-deterministic data as an initial seed. */
     microtime(&tt);
@@ -294,26 +280,24 @@
     }
     
     /* turn the data around */
-    perr = prngOutput(gPrngRef, (BYTE*) buffer, sizeof (buffer));
+    perr = prngOutput(gPrngRef, (BYTE*)buffer, sizeof (buffer));
     
     /* and scramble it some more */
     perr = prngForceReseed(gPrngRef, RESEED_TICKS);
-    }
     
     /* make a mutex to control access */
-    gYarrowGrpAttr = lck_grp_attr_alloc_init();
-    gYarrowGrp     = lck_grp_alloc_init("random", gYarrowGrpAttr);
-    gYarrowAttr    = lck_attr_alloc_init();
-    gYarrowMutex   = lck_mtx_alloc_init(gYarrowGrp, gYarrowAttr);
+    gYarrowMutex = mutex_alloc(0);
 	
 	fips_initialize ();
 }
+
+const Block kKnownAnswer = {0x92b404e5, 0x56588ced, 0x6c1acd4e, 0xbf053f68, 0x9f73a93};
 
 void
 fips_initialize(void)
 {
-	/* Read the initial value of g_xkey from yarrow */
-	prngOutput (gPrngRef, (BYTE*) &g_xkey, sizeof (g_xkey));
+	/* So that we can do the self test, set the seed to zero */
+	memset(&g_xkey, 0, sizeof(g_xkey));
 	
 	/* initialize our SHA1 generator */
 	SHA1Init (&g_sha1_ctx);
@@ -321,7 +305,20 @@
 	/* other initializations */
 	memset (zeros, 0, sizeof (zeros));
 	g_bytes_used = 0;
-	random_block(g_random_data);
+	random_block(g_random_data, FALSE);
+	
+	// check here to see if we got the initial data we were expecting
+	int i;
+	for (i = 0; i < kBSize; ++i)
+	{
+		if (kKnownAnswer[i] != g_random_data[i])
+		{
+			panic("FIPS random self test failed");
+		}
+	}
+
+	// now do the random block again to make sure that userland doesn't get predictable data
+	random_block(g_random_data, TRUE);
 }
 
 /*
@@ -339,10 +336,8 @@
 	/* install us in the file system */
 	gRandomInstalled = 1;
 
-#ifndef ARM_BOARD_CONFIG_S5L8900XFPGA_1136JFS
 	/* setup yarrow and the mutex */
 	PreliminarySetup();
-#endif
 
 	ret = cdevsw_add(RANDOM_MAJOR, &random_cdevsw);
 	if (ret < 0) {
@@ -433,7 +428,7 @@
     }
     
     /* get control of the Yarrow instance, Yarrow is NOT thread safe */
-    lck_mtx_lock(gYarrowMutex);
+    mutex_lock(gYarrowMutex);
     
     /* Security server is sending us entropy */
 
@@ -446,7 +441,7 @@
             goto /*ugh*/ error_exit;
         
         /* put it in Yarrow */
-        if (prngInput(gPrngRef, (BYTE*) rdBuffer,
+        if (prngInput(gPrngRef, (BYTE*)rdBuffer,
 			bytesToInput, SYSTEM_SOURCE,
         	bytesToInput * 8) != 0) {
             retCode = EIO;
@@ -463,15 +458,14 @@
     /* retCode should be 0 at this point */
     
 error_exit: /* do this to make sure the mutex unlocks. */
-    lck_mtx_unlock(gYarrowMutex);
+    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 random_read(__unused dev_t dev, struct uio *uio, __unused int ioflag)
 {
     int retCode = 0;
 	
@@ -479,9 +473,8 @@
         return (ENOTSUP);
 
    /* lock down the mutex */
-    lck_mtx_lock(gYarrowMutex);
-
-    CheckReseed();
+    mutex_lock(gYarrowMutex);
+
 	int bytes_remaining = uio_resid(uio);
     while (bytes_remaining > 0 && retCode == 0) {
         /* get the user's data */
@@ -490,14 +483,14 @@
 		int bytes_available = kBSizeInBytes - g_bytes_used;
         if (bytes_available == 0)
 		{
-			random_block(g_random_data);
+			random_block(g_random_data, TRUE);
 			g_bytes_used = 0;
 			bytes_available = kBSizeInBytes;
 		}
 		
 		bytes_to_read = min (bytes_remaining, bytes_available);
 		
-        retCode = uiomove(((caddr_t)g_random_data)+ g_bytes_used, bytes_to_read, uio);
+        retCode = uiomove(((u_int8_t*)g_random_data)+ g_bytes_used, bytes_to_read, uio);
         g_bytes_used += bytes_to_read;
 
         if (retCode != 0)
@@ -509,7 +502,7 @@
     retCode = 0;
     
 error_exit:
-    lck_mtx_unlock(gYarrowMutex);
+    mutex_unlock(gYarrowMutex);
     return retCode;
 }
 
@@ -518,14 +511,11 @@
 read_random(void* buffer, u_int numbytes)
 {
     if (gYarrowMutex == 0) { /* are we initialized? */
-#ifndef ARM_BOARD_CONFIG_S5L8900XFPGA_1136JFS
         PreliminarySetup ();
-#endif
-    }
-    
-    lck_mtx_lock(gYarrowMutex);
-    CheckReseed();
-
+    }
+    
+    mutex_lock(gYarrowMutex);
+	
 	int bytes_read = 0;
 
 	int bytes_remaining = numbytes;
@@ -533,18 +523,18 @@
         int bytes_to_read = min(bytes_remaining, kBSizeInBytes - g_bytes_used);
         if (bytes_to_read == 0)
 		{
-			random_block(g_random_data);
+			random_block(g_random_data, TRUE);
 			g_bytes_used = 0;
 			bytes_to_read = min(bytes_remaining, kBSizeInBytes);
 		}
 		
-		memmove ((u_int8_t*) buffer + bytes_read, ((u_int8_t*)g_random_data)+ g_bytes_used, bytes_to_read);
+		memmove (buffer, ((u_int8_t*)g_random_data)+ bytes_read, bytes_to_read);
 		g_bytes_used += bytes_to_read;
 		bytes_read += bytes_to_read;
 		bytes_remaining -= bytes_to_read;
     }
 
-    lck_mtx_unlock(gYarrowMutex);
+    mutex_unlock(gYarrowMutex);
 }
 
 /*
@@ -558,7 +548,3 @@
 	return (buf);
 }
 
-void
-CheckReseed(void)
-{
-}