1/*
2 * Copyright (c) 2013 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_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. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28
29#ifndef	_PRNG_RANDOM_H_
30#define	_PRNG_RANDOM_H_
31
32__BEGIN_DECLS
33
34#ifdef XNU_KERNEL_PRIVATE
35
36#define	ENTROPY_BUFFER_BYTE_SIZE	64
37
38#define	ENTROPY_BUFFER_SIZE		ENTROPY_BUFFER_BYTE_SIZE/sizeof(uint32_t)
39
40typedef struct entropy_data {
41	uint32_t	*index_ptr;
42	uint32_t	buffer[ENTROPY_BUFFER_SIZE];
43} entropy_data_t;
44
45extern entropy_data_t EntropyData;
46
47/* Trace codes for DBG_SEC_KERNEL: */
48#define ENTROPY_READ(n)	SECURITYDBG_CODE(DBG_SEC_KERNEL, n) /* n: 0 .. 3 */
49
50/*
51 * Early_random implementation params: */
52#define	EARLY_RANDOM_SEED_SIZE		(16)
53#define	EARLY_RANDOM_STATE_STATIC_SIZE	(256)
54
55#if defined (__x86_64__)
56#define current_prng_context()	(current_cpu_datap()->cpu_prng)
57#define master_prng_context()	(cpu_datap(master_cpu)->cpu_prng)
58#else
59#error architecture unknown
60#endif
61
62#include <corecrypto/ccdrbg.h>
63#include <corecrypto/ccsha1.h>
64
65typedef struct	ccdrbg_info ccdrbg_info_t;
66typedef void  (*ccdrbg_factory_t)(ccdrbg_info_t *info, const void *custom);
67
68extern void	ccdrbg_factory_yarrow(ccdrbg_info_t *info, const void *custom);
69
70void		prng_factory_register(ccdrbg_factory_t factory);
71void		prng_cpu_init(int cpu);
72
73void		entropy_buffer_read(char *buffer, unsigned int *count);
74void		entropy_boot_trace(void);
75
76/*
77 * Wrapper for requesting a CCDRBG operation.
78 * This macro makes the DRBG call with pre-emption disabled to ensure that
79 * any attempt to block will cause a panic. And the operation is timed and
80 * cannot exceed 10msec (for development kernels).
81 * But skip this while we retain Yarrow.
82 */
83#define YARROW 1
84#if YARROW
85#define PRNG_CCDRBG(op)					\
86MACRO_BEGIN						\
87	op;						\
88MACRO_END
89#else
90#define PRNG_CCDRBG(op)					\
91MACRO_BEGIN						\
92	uint64_t	start;				\
93	uint64_t	stop;				\
94	disable_preemption();				\
95	start = mach_absolute_time();			\
96	op;						\
97	stop = mach_absolute_time();			\
98	enable_preemption();				\
99	assert(stop - start < 10*NSEC_PER_MSEC ||	\
100	       machine_timeout_suspended());		\
101	(void) start;					\
102	(void) stop;					\
103MACRO_END
104#endif
105
106#endif /* XNU_KERNEL_PRIVATE */
107
108/* /dev/random's PRNG is reseeded after generating this many bytes: */
109#define	RESEED_BYTES (17597)
110
111__END_DECLS
112
113#endif /* _PRNG_RANDOM_H_ */
114