1/*
2 * Copyright (c) 2000-2004 Apple Computer, Inc. All Rights Reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. Please obtain a copy of the License at
10 * http://www.opensource.apple.com/apsl/ and read it before using this
11 * file.
12 *
13 * The Original Code and all software distributed under the License are
14 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
15 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
16 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
18 * Please see the License for the specific language governing rights and
19 * limitations under the License.
20 *
21 * @APPLE_LICENSE_HEADER_END@
22 */
23
24
25//
26// devrandom - RNG operations based on /dev/random
27//
28#ifndef _H_DEVRANDOM
29#define _H_DEVRANDOM
30
31#include <security_utilities/utilities.h>
32#include <security_utilities/unix++.h>
33#include <security_utilities/globalizer.h>
34
35
36namespace Security {
37
38
39//
40// This RNG uses /dev/random.
41// It is not repeatable. AddEntropy() contributes random entropy to a global pool (only).
42//
43class DevRandomGenerator {
44	struct Readonly : public UnixPlusPlus::FileDesc {
45		Readonly() { open("/dev/random", O_RDONLY); }
46	};
47
48	struct Writable : public UnixPlusPlus::FileDesc {
49		Writable() { open("/dev/random", O_RDWR); }
50	};
51
52public:
53    DevRandomGenerator(bool writable = false);
54
55    void random(void *data, size_t length);
56    void addEntropy(const void *data, size_t length);
57
58private:
59    static ModuleNexus<Readonly> mReader;
60	static ModuleNexus<Writable> mWriter;
61};
62
63
64}; 	// end namespace Security
65
66
67#endif //_H_DEVRANDOM
68