xnu-792.22.5.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 2339353fe95cd6c625e9ae95434148026b5fe6c0..6f99d775d205f5e1eb1fad86c65703acc0adae51 100644 (file)
--- a/bsd/dev/random/randomdev.c
+++ b/bsd/dev/random/randomdev.c
@@ -1,31 +1,29 @@
 /*
 /*

- * Copyright (c) 2006 Apple Computer, 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.
- *
- * 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 
+ * 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

  * limitations under the License.
  * limitations under the License.

- *
- * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
+ * 
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@

  */
 
 #include <sys/param.h>
  */
 
 #include <sys/param.h>


@@ -93,6 +91,7 @@ typedef BlockWord Block[kBSize];
 void add_blocks(Block a, Block b, BlockWord carry);
 void fips_initialize(void);
 void random_block(Block b);
 void add_blocks(Block a, Block b, BlockWord carry);
 void fips_initialize(void);
 void random_block(Block b);

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

 
 /*
  * Get 120 bits from yarrow
 
 /*
  * Get 120 bits from yarrow


@@ -122,35 +121,128 @@ char zeros[(512 - kBSizeInBits) / 8];
 Block g_xkey;
 Block g_random_data;
 int g_bytes_used;
 Block g_xkey;
 Block g_random_data;
 int g_bytes_used;

+unsigned char g_SelfTestInitialized = 0;
+u_int32_t gLastBlockChecksum;
+
+static const u_int32_t g_crc_table[] =
+{
+       0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419, 0x706AF48F, 0xE963A535, 0x9E6495A3,
+       0x0EDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988, 0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91,
+       0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE, 0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7,
+       0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC, 0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5,
+       0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172, 0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B,
+       0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940, 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59,
+       0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F,
+       0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924, 0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D,
+       0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433,
+       0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01,
+       0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E, 0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457,
+       0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C, 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65,
+       0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2, 0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB,
+       0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0, 0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9,
+       0x5005713C, 0x270241AA, 0xBE0B1010, 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F,
+       0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17, 0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD,
+       0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A, 0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683,
+       0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8, 0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1,
+       0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, 0x806567CB, 0x196C3671, 0x6E6B06E7,
+       0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC, 0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5,
+       0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252, 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B,
+       0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79,
+       0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236, 0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F,
+       0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D,
+       0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A, 0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713,
+       0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38, 0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21,
+       0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777,
+       0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C, 0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45,
+       0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2, 0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB,
+       0xAED16A4A, 0xD9D65ADC, 0x40DF0B66, 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9,
+       0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF,
+       0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94, 0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D,
+};

 
 /*
  * Setup for fips compliance
  */
 
 
 /*
  * Setup for fips compliance
  */
 

+/*
+ * calculate a crc-32 checksum
+ */
+u_int32_t CalculateCRC(u_int8_t* buffer, size_t length)
+{
+       u_int32_t crc = 0;
+       
+       size_t i;
+       for (i = 0; i < length; ++i)
+       {
+               u_int32_t temp = (crc ^ ((u_int32_t) buffer[i])) & 0xFF;
+               crc = (crc >> 8) ^ g_crc_table[temp];
+       }
+       
+       return crc;
+}
+

 /*
  * get a random block of data per fips 186-2
  */
 void
 random_block(Block b)
 {
 /*
  * 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);
+       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);

 
 

-       // 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));
+               // 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));
+               
+               // calculate the CRC-32 of the block
+               u_int32_t new_crc = CalculateCRC(g_sha1_ctx.h.b8, sizeof (Block));
+               
+               // make sure we don't repeat
+               int cmp = new_crc == gLastBlockChecksum;
+               gLastBlockChecksum = new_crc;
+               if (!g_SelfTestInitialized)
+               {
+                       g_SelfTestInitialized = 1;
+                       return;
+               }
+               else if (!cmp)
+               {
+                       return;
+               }
+               
+               repeatCount += 1;
+               
+               // fix up the next value of g_xkey
+               add_blocks (g_xkey, b, 1);
+       } while (repeatCount < 2);

        
        

-       // fix up the next value of g_xkey
-       add_blocks (g_xkey, b, 1);
+       /*
+        * If we got here, three sucessive checksums of the random number
+        * generator have been the same.  Since the odds of this happening are
+        * 1 in 18,446,744,073,709,551,616, (1 in 18 quintillion) one of the following has
+        * most likely happened:
+        *
+        * 1: There is a significant bug in this code.
+        * 2: There has been a massive system failure.
+        * 3: The universe has ceased to exist.
+        *
+        * There is no good way to recover from any of these cases. We
+        * therefore panic.
+        */
+        
+        panic("FIPS random self-test failed.");

 }
 
 /*
 }
 
 /*


@@ -411,6 +503,8 @@ read_random(void* buffer, u_int numbytes)
     }
     
     mutex_lock(gYarrowMutex);
     }
     
     mutex_lock(gYarrowMutex);

+       
+       int bytes_read = 0;

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


@@ -422,9 +516,9 @@ read_random(void* buffer, u_int numbytes)
                        bytes_to_read = min(bytes_remaining, kBSizeInBytes);
                }
                
                        bytes_to_read = min(bytes_remaining, kBSizeInBytes);
                }
                

-               memmove (buffer, ((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;
                g_bytes_used += bytes_to_read;

-               
+               bytes_read += bytes_to_read;

                bytes_remaining -= bytes_to_read;
     }
 
                bytes_remaining -= bytes_to_read;
     }