1/*
2 * Copyright (c) 2006 Kungliga Tekniska Högskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * 3. Neither the name of the Institute nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#include <config.h>
35
36#include <stdio.h>
37#include <stdlib.h>
38#include <rand.h>
39#include <heim_threads.h>
40
41#include <roken.h>
42
43#include "randi.h"
44
45#ifdef __APPLE_TARGET_EMBEDDED__
46
47/*
48 * Unix /dev/random
49 */
50
51int
52_hc_unix_device_fd(int flags, const char **fn)
53{
54    static const char *rnd_devices[] = {
55	"/dev/urandom",
56	"/dev/random",
57	"/dev/srandom",
58	"/dev/arandom",
59	NULL
60    };
61    const char **p;
62
63    for(p = rnd_devices; *p; p++) {
64	int fd = open(*p, flags | O_NDELAY);
65	if(fd >= 0) {
66	    if (fn)
67		*fn = *p;
68	    rk_cloexec(fd);
69	    return fd;
70	}
71    }
72    return -1;
73}
74
75static void
76unix_seed(const void *indata, int size)
77{
78    int fd;
79
80    if (size <= 0)
81	return;
82
83    fd = _hc_unix_device_fd(O_WRONLY, NULL);
84    if (fd < 0)
85	return;
86
87    write(fd, indata, size);
88    close(fd);
89
90}
91
92
93static int
94unix_bytes(unsigned char *outdata, int size)
95{
96    ssize_t count;
97    int fd;
98
99    if (size < 0)
100	return 0;
101    else if (size == 0)
102	return 1;
103
104    fd = _hc_unix_device_fd(O_RDONLY, NULL);
105    if (fd < 0)
106	return 0;
107
108    while (size > 0) {
109	count = read(fd, outdata, size);
110	if (count < 0 && errno == EINTR)
111	    continue;
112	else if (count <= 0) {
113	    close(fd);
114	    return 0;
115	}
116	outdata += count;
117	size -= count;
118    }
119    close(fd);
120
121    return 1;
122}
123
124static void
125unix_cleanup(void)
126{
127}
128
129static void
130unix_add(const void *indata, int size, double entropi)
131{
132    unix_seed(indata, size);
133}
134
135static int
136unix_pseudorand(unsigned char *outdata, int size)
137{
138    return unix_bytes(outdata, size);
139}
140
141static int
142unix_status(void)
143{
144    int fd;
145
146    fd = _hc_unix_device_fd(O_RDONLY, NULL);
147    if (fd < 0)
148	return 0;
149    close(fd);
150
151    return 1;
152}
153
154const RAND_METHOD hc_rand_unix_method = {
155    unix_seed,
156    unix_bytes,
157    unix_cleanup,
158    unix_add,
159    unix_pseudorand,
160    unix_status
161};
162
163const RAND_METHOD *
164RAND_unix_method(void)
165{
166    return &hc_rand_unix_method;
167}
168
169#endif
170