cdsa/cdsa_utilities/devrandom.cpp

   1 /*
   2  * Copyright (c) 2000-2001 Apple Computer, Inc. All Rights Reserved.
   3  *
   4  * The contents of this file constitute Original Code as defined in and are
   5  * subject to the Apple Public Source License Version 1.2 (the 'License').
   6  * You may not use this file except in compliance with the License. Please obtain
   7  * a copy of the License at http://www.apple.com/publicsource and read it before
   8  * using this file.
   9  *
  10  * This Original Code and all software distributed under the License are
  11  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS
  12  * OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, INCLUDING WITHOUT
  13  * LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
  14  * PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. Please see the License for the
  15  * specific language governing rights and limitations under the License.
  16  */
  17
  18
  19 //
  20 // devrandom - RNG operations based on /dev/random
  21 //
  22 #include <Security/devrandom.h>
  23
  24
  25 namespace Security {
  26
  27
  28 //
  29 // DevRandomGenerator objects immediately open their file descriptors
  30 //
  31 DevRandomGenerator::DevRandomGenerator(bool writable)
  32 {
  33     mDevRandom.open("/dev/random", writable ? O_RDWR : O_RDONLY);
  34 }
  35
  36
  37 //
  38 // Standard generate (directly from /dev/random)
  39 //
  40 void DevRandomGenerator::random(void *data, size_t length)
  41 {
  42     mDevRandom.read(data, length);
  43 }
  44
  45
  46 //
  47 // If you opened for writing, you add entropy to the global pool here
  48 //
  49 void DevRandomGenerator::addEntropy(const void *data, size_t length)
  50 {
  51     mDevRandom.write(data, length);
  52 }
  53
  54
  55 }       // end namespace Security