1/*
2 * Copyright (c) 1999-2001,2005-2008,2010-2012,2014 Apple 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 * sslRand.c - Randomness
26 */
27
28/* THIS FILE CONTAINS KERNEL CODE */
29
30#include "sslRand.h"
31#include "sslDebug.h"
32#include <AssertMacros.h>
33
34#ifdef KERNEL
35
36void read_random(void* buffer, u_int numBytes);
37
38#else
39
40#include <TargetConditionals.h>
41
42#ifdef TARGET_OS_EMBEDDED
43#include <Security/SecRandom.h>
44#else
45static
46int sslRandMacOSX(void *data, size_t len)
47{
48    static int random_fd = -1;
49
50    if (random_fd == -1) {
51        random_fd = open("/dev/random", O_RDONLY);
52        if (random_fd == -1) {
53            sslErrorLog("sslRand: error opening /dev/random: %s\n",
54                        strerror(errno));
55            return -1;
56        }
57    }
58
59    ssize_t bytesRead = read(random_fd, data, len);
60    if (bytesRead != len) {
61        sslErrorLog("sslRand: error reading %lu bytes from /dev/random: %s\n",
62                    len, strerror(errno));
63        serr = -1;
64    }
65
66    return serr;
67}
68#endif /* TARGET_OS_EMBEDDED */
69
70#endif /* KERNEL */
71
72/*
73 * Common RNG function.
74 */
75int sslRand(SSLBuffer *buf)
76{
77	check(buf != NULL);
78	check(buf->data != NULL);
79
80	if(buf->length == 0) {
81		sslErrorLog("sslRand: zero buf->length\n");
82		return 0;
83	}
84
85#ifdef KERNEL
86    read_random(buf->data, (u_int)buf->length);
87    return 0;
88#else
89#ifdef TARGET_OS_EMBEDDED
90	return SecRandomCopyBytes(kSecRandomDefault, buf->length, buf->data);
91#else
92    return sslRandMacOSX(ctx, buf);
93#endif
94#endif
95}
96