xnu-1504.9.26.tar.gz

[apple/xnu.git] / bsd / dev / random / randomdev.c

diff --git a/bsd/dev/random/randomdev.c b/bsd/dev/random/randomdev.c
index 4a7741e2a78c551c47ebda5d9517d05b8feeed08..c081bd20904ca64b7dc49b091f1cb734eac98ad6 100644 (file)
--- a/bsd/dev/random/randomdev.c
+++ b/bsd/dev/random/randomdev.c
@@ -1,5 +1,5 @@
 /*
 /*

- * Copyright (c) 1999-2006 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 1999-2009 Apple, Inc. All rights reserved.

  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * 
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * 


@@ -26,6 +26,17 @@
  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 
  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 

+/*
+       WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING!
+       
+       THIS FILE IS NEEDED TO PASS FIPS ACCEPTANCE FOR THE RANDOM NUMBER GENERATOR.
+       IF YOU ALTER IT IN ANY WAY, WE WILL NEED TO GO THOUGH FIPS ACCEPTANCE AGAIN,
+       AN OPERATION THAT IS VERY EXPENSIVE AND TIME CONSUMING.  IN OTHER WORDS,
+       DON'T MESS WITH THIS FILE.
+
+       WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING!
+*/
+

 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/proc.h>
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/proc.h>


@@ -43,11 +54,14 @@
 
 #include <dev/random/randomdev.h>
 #include <dev/random/YarrowCoreLib/include/yarrow.h>
 
 #include <dev/random/randomdev.h>
 #include <dev/random/YarrowCoreLib/include/yarrow.h>

-#include <libkern/crypto/sha1.h>
+
+#include <libkern/OSByteOrder.h>

 
 #include <mach/mach_time.h>
 #include <machine/machine_routines.h>
 
 
 #include <mach/mach_time.h>
 #include <machine/machine_routines.h>
 

+#include "fips_sha1.h"
+

 #define RANDOM_MAJOR  -1 /* let the kernel pick the device number */
 
 d_ioctl_t       random_ioctl;
 #define RANDOM_MAJOR  -1 /* let the kernel pick the device number */
 
 d_ioctl_t       random_ioctl;


@@ -74,6 +88,18 @@ static struct cdevsw random_cdevsw =
        0                                       /* type */
 };
 
        0                                       /* type */
 };
 

+
+/*
+       WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING!
+
+       ANY CODE PROTECTED UNDER "#ifdef __arm__" IS SERIOUSLY SUPPOSED TO BE THERE!
+       IF YOU REMOVE ARM CODE, RANDOM WILL NOT MEAN ANYTHING FOR iPHONES ALL OVER.
+       PLEASE DON'T TOUCH __arm__ CODE IN THIS FILE!
+
+       WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING!
+*/
+
+

 /* Used to detect whether we've already been initialized */
 static int gRandomInstalled = 0;
 static PrngRef gPrngRef;
 /* Used to detect whether we've already been initialized */
 static int gRandomInstalled = 0;
 static PrngRef gPrngRef;


@@ -83,23 +109,19 @@ static lck_attr_t *gYarrowAttr;
 static lck_grp_attr_t *gYarrowGrpAttr;
 static lck_mtx_t *gYarrowMutex = 0;
 
 static lck_grp_attr_t *gYarrowGrpAttr;
 static lck_mtx_t *gYarrowMutex = 0;
 

-void CheckReseed(void);
-

 #define RESEED_TICKS 50 /* how long a reseed operation can take */
 
 
 #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 u_int8_t BlockWord;
+enum {kBSize = 20};

 typedef BlockWord Block[kBSize];
 typedef BlockWord Block[kBSize];

+enum {kBlockSize = sizeof(Block)};

 
 /* define prototypes to keep the compiler happy... */
 
 void add_blocks(Block a, Block b, BlockWord carry);
 void fips_initialize(void);
 
 /* 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);
+void random_block(Block b, int addOptional);

 u_int32_t CalculateCRC(u_int8_t* buffer, size_t length);
 
 /*
 u_int32_t CalculateCRC(u_int8_t* buffer, size_t length);
 
 /*


@@ -112,26 +134,26 @@ u_int32_t CalculateCRC(u_int8_t* buffer, size_t length);
 void
 add_blocks(Block a, Block b, BlockWord carry)
 {
 void
 add_blocks(Block a, Block b, BlockWord carry)
 {

-       int i = kBSize;
-       while (--i >= 0)
+       int i = kBlockSize - 1;
+       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;
+               u_int32_t c = (u_int32_t)carry +
+                                         (u_int32_t)a[i] +
+                                         (u_int32_t)b[i];
+               a[i] = c & 0xff;
+               carry = c >> 8;
+               i -= 1;

        }
 }
 
 
 
        }
 }
 
 
 

-struct sha1_ctxt g_sha1_ctx;
-char zeros[(512 - kBSizeInBits) / 8];
-Block g_xkey;
-Block g_random_data;
-int g_bytes_used;
-unsigned char g_SelfTestInitialized = 0;
-u_int32_t gLastBlockChecksum;
+static char zeros[(512 - kBSize * 8) / 8];
+static Block g_xkey;
+static Block g_random_data;
+static int g_bytes_used;
+static unsigned char g_SelfTestInitialized = 0;
+static u_int32_t gLastBlockChecksum;

 
 static const u_int32_t g_crc_table[] =
 {
 
 static const u_int32_t g_crc_table[] =
 {


@@ -194,29 +216,52 @@ u_int32_t CalculateCRC(u_int8_t* buffer, size_t length)
  * get a random block of data per fips 186-2
  */
 void
  * get a random block of data per fips 186-2
  */
 void

-random_block(Block b)
+random_block(Block b, int addOptional)

 {
 {

+       SHA1_CTX sha1_ctx;
+       

        int repeatCount = 0;
        do
        {
                // do one iteration
        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)
+               {
+                       // create an xSeed to add.
+                       Block xSeed;
+                       prngOutput (gPrngRef, (BYTE*) &xSeed, sizeof (xSeed));
+                       
+                       // add the seed to the previous value of g_xkey
+                       add_blocks (g_xkey, xSeed, 0);
+               }
+               
+               // initialize the value of H
+               FIPS_SHA1Init(&sha1_ctx);
+               
+               // to stay compatible with the FIPS specification, we need to flip the bytes in
+               // g_xkey to little endian byte order.  In our case, this makes exactly no difference
+               // (random is random), but we need to do it anyway to keep FIPS happy
+               

                // compute "G"
                // compute "G"

-               SHA1Update (&g_sha1_ctx, (const u_int8_t *) &g_xkey, sizeof (g_xkey));
+               FIPS_SHA1Update(&sha1_ctx, g_xkey, kBlockSize);

                
                // add zeros to fill the internal SHA-1 buffer
                
                // add zeros to fill the internal SHA-1 buffer

-               SHA1Update (&g_sha1_ctx, (const u_int8_t *)zeros, sizeof (zeros));
+               FIPS_SHA1Update (&sha1_ctx, (const u_int8_t *)zeros, sizeof (zeros));
+               
+               // we have to do a byte order correction here because the sha1 math is being done internally
+               // as u_int32_t, not a stream of bytes.  Since we maintain our data as a byte stream, we need
+               // to convert

                
                

-               // write the resulting block
-               memmove(b, g_sha1_ctx.h.b8, sizeof (Block));
+               u_int32_t* finger = (u_int32_t*) b;
+               
+               unsigned j;
+               for (j = 0; j < kBlockSize / sizeof (u_int32_t); ++j)
+               {
+                       *finger++ = OSSwapHostToBigInt32(sha1_ctx.h.b32[j]);
+               }               

                
                // calculate the CRC-32 of the block
                
                // calculate the CRC-32 of the block

-               u_int32_t new_crc = CalculateCRC(g_sha1_ctx.h.b8, sizeof (Block));
+               u_int32_t new_crc = CalculateCRC(sha1_ctx.h.b8, sizeof (Block));

                
                // make sure we don't repeat
                int cmp = new_crc == gLastBlockChecksum;
                
                // make sure we don't repeat
                int cmp = new_crc == gLastBlockChecksum;


@@ -272,7 +317,6 @@ PreliminarySetup(void)
        /* clear the error flag, reads and write should then work */
     gRandomError = 0;
 
        /* clear the error flag, reads and write should then work */
     gRandomError = 0;
 

-   {

     struct timeval tt;
     char buffer [16];
 
     struct timeval tt;
     char buffer [16];
 


@@ -298,7 +342,6 @@ PreliminarySetup(void)
     
     /* and scramble it some more */
     perr = prngForceReseed(gPrngRef, RESEED_TICKS);
     
     /* and scramble it some more */
     perr = prngForceReseed(gPrngRef, RESEED_TICKS);

-    }

     
     /* make a mutex to control access */
     gYarrowGrpAttr = lck_grp_attr_alloc_init();
     
     /* make a mutex to control access */
     gYarrowGrpAttr = lck_grp_attr_alloc_init();


@@ -309,19 +352,27 @@ PreliminarySetup(void)
        fips_initialize ();
 }
 
        fips_initialize ();
 }
 

+const Block kKnownAnswer = {0x92, 0xb4, 0x04, 0xe5, 0x56, 0x58, 0x8c, 0xed, 0x6c, 0x1a, 0xcd, 0x4e, 0xbf, 0x05, 0x3f, 0x68, 0x09, 0xf7, 0x3a, 0x93};
+

 void
 fips_initialize(void)
 {
 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);
+       /* So that we can do the self test, set the seed to zero */
+       memset(&g_xkey, 0, sizeof(g_xkey));

        
        /* other initializations */
        memset (zeros, 0, sizeof (zeros));
        g_bytes_used = 0;
        
        /* 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
+       if (memcmp(kKnownAnswer, g_random_data, kBlockSize) != 0)
+       {
+               panic("FIPS random self test failed");
+       }
+       
+       // now do the random block again to make sure that userland doesn't get predicatable data
+       random_block(g_random_data, TRUE);

 }
 
 /*
 }
 
 /*


@@ -339,10 +390,8 @@ random_init(void)
        /* install us in the file system */
        gRandomInstalled = 1;
 
        /* install us in the file system */
        gRandomInstalled = 1;
 

-#ifndef ARM_BOARD_CONFIG_S5L8900XFPGA_1136JFS

        /* setup yarrow and the mutex */
        PreliminarySetup();
        /* setup yarrow and the mutex */
        PreliminarySetup();

-#endif

 
        ret = cdevsw_add(RANDOM_MAJOR, &random_cdevsw);
        if (ret < 0) {
 
        ret = cdevsw_add(RANDOM_MAJOR, &random_cdevsw);
        if (ret < 0) {


@@ -439,7 +488,6 @@ random_write (__unused dev_t dev, struct uio *uio, __unused int ioflag)
 
     while (uio_resid(uio) > 0 && retCode == 0) {
         /* get the user's data */
 
     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)
         int bytesToInput = min(uio_resid(uio), sizeof (rdBuffer));
         retCode = uiomove(rdBuffer, bytesToInput, uio);
         if (retCode != 0)


@@ -481,18 +529,18 @@ random_read(__unused dev_t dev, struct uio *uio, __unused int ioflag)
    /* lock down the mutex */
     lck_mtx_lock(gYarrowMutex);
 
    /* lock down the mutex */
     lck_mtx_lock(gYarrowMutex);
 

-    CheckReseed();
+

        int bytes_remaining = uio_resid(uio);
     while (bytes_remaining > 0 && retCode == 0) {
         /* get the user's data */
                int bytes_to_read = 0;
                
        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;
+               int bytes_available = kBlockSize - g_bytes_used;

         if (bytes_available == 0)
                {
         if (bytes_available == 0)
                {

-                       random_block(g_random_data);
+                       random_block(g_random_data, TRUE);

                        g_bytes_used = 0;
                        g_bytes_used = 0;

-                       bytes_available = kBSizeInBytes;
+                       bytes_available = kBlockSize;

                }
                
                bytes_to_read = min (bytes_remaining, bytes_available);
                }
                
                bytes_to_read = min (bytes_remaining, bytes_available);


@@ -518,24 +566,20 @@ void
 read_random(void* buffer, u_int numbytes)
 {
     if (gYarrowMutex == 0) { /* are we initialized? */
 read_random(void* buffer, u_int numbytes)
 {
     if (gYarrowMutex == 0) { /* are we initialized? */

-#ifndef ARM_BOARD_CONFIG_S5L8900XFPGA_1136JFS

         PreliminarySetup ();
         PreliminarySetup ();

-#endif

     }
     
     lck_mtx_lock(gYarrowMutex);
     }
     
     lck_mtx_lock(gYarrowMutex);

-    CheckReseed();
-

        int bytes_read = 0;
 
        int bytes_remaining = numbytes;
     while (bytes_remaining > 0) {
        int bytes_read = 0;
 
        int bytes_remaining = numbytes;
     while (bytes_remaining > 0) {

-        int bytes_to_read = min(bytes_remaining, kBSizeInBytes - g_bytes_used);
+        int bytes_to_read = min(bytes_remaining, kBlockSize - g_bytes_used);

         if (bytes_to_read == 0)
                {
         if (bytes_to_read == 0)
                {

-                       random_block(g_random_data);
+                       random_block(g_random_data, TRUE);

                        g_bytes_used = 0;
                        g_bytes_used = 0;

-                       bytes_to_read = min(bytes_remaining, kBSizeInBytes);
+                       bytes_to_read = min(bytes_remaining, kBlockSize);

                }
                
                memmove ((u_int8_t*) buffer + bytes_read, ((u_int8_t*)g_random_data)+ g_bytes_used, bytes_to_read);
                }
                
                memmove ((u_int8_t*) buffer + bytes_read, ((u_int8_t*)g_random_data)+ g_bytes_used, bytes_to_read);


@@ -548,17 +592,13 @@ read_random(void* buffer, u_int numbytes)
 }
 
 /*
 }
 
 /*

- * Return an unsigned long pseudo-random number.
+ * Return an u_int32_t pseudo-random number.

  */
  */

-u_long
+u_int32_t

 RandomULong(void)
 {
 RandomULong(void)
 {

-       u_long buf;
+       u_int32_t buf;

        read_random(&buf, sizeof (buf));
        return (buf);
 }
 
        read_random(&buf, sizeof (buf));
        return (buf);
 }
 

-void
-CheckReseed(void)
-{
-}