Line data Source code
1 : /*
2 : * Copyright (c) 1995, 1996, 1997, 1999, 2007 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 :
40 : #include <roken.h>
41 :
42 : #include "randi.h"
43 :
44 : #ifndef WIN32 /* don't bother with this on windows */
45 :
46 : static volatile int counter;
47 : static volatile unsigned char *gdata; /* Global data */
48 : static volatile int igdata; /* Index into global data */
49 : static int gsize;
50 :
51 : static
52 : RETSIGTYPE
53 0 : sigALRM(int sig)
54 : {
55 0 : if (igdata < gsize)
56 0 : gdata[igdata++] ^= counter & 0xff;
57 :
58 : #ifndef HAVE_SIGACTION
59 : signal(SIGALRM, sigALRM); /* Reinstall SysV signal handler */
60 : #endif
61 0 : SIGRETURN(0);
62 : }
63 :
64 : #ifndef HAVE_SETITIMER
65 : static void
66 : pacemaker(struct timeval *tv)
67 : {
68 : fd_set fds;
69 : pid_t pid;
70 : pid = getppid();
71 : while(1){
72 : FD_ZERO(&fds);
73 : FD_SET(0, &fds);
74 : select(1, &fds, NULL, NULL, tv);
75 : kill(pid, SIGALRM);
76 : }
77 : }
78 : #endif
79 :
80 : #ifdef HAVE_SIGACTION
81 : /* XXX ugly hack, should perhaps use function from roken */
82 : static RETSIGTYPE
83 0 : (*fake_signal(int sig, RETSIGTYPE (*f)(int)))(int)
84 : {
85 : struct sigaction sa, osa;
86 0 : sa.sa_handler = f;
87 0 : sa.sa_flags = 0;
88 0 : sigemptyset(&sa.sa_mask);
89 0 : sigaction(sig, &sa, &osa);
90 0 : return osa.sa_handler;
91 : }
92 : #define signal(S, F) fake_signal((S), (F))
93 : #endif
94 :
95 : #endif /* WIN32*/
96 :
97 : /*
98 : *
99 : */
100 :
101 : static void
102 0 : timer_seed(const void *indata, int size)
103 : {
104 0 : }
105 :
106 : static int
107 0 : timer_bytes(unsigned char *outdata, int size)
108 : {
109 : #ifdef WIN32
110 : return 0;
111 : #else /* WIN32 */
112 : struct itimerval tv, otv;
113 : RETSIGTYPE (*osa)(int);
114 : int i, j;
115 : #ifndef HAVE_SETITIMER
116 : RETSIGTYPE (*ochld)(int);
117 : pid_t pid;
118 : #endif
119 :
120 0 : gdata = outdata;
121 0 : gsize = size;
122 0 : igdata = 0;
123 :
124 0 : osa = signal(SIGALRM, sigALRM);
125 :
126 : /* Start timer */
127 0 : tv.it_value.tv_sec = 0;
128 0 : tv.it_value.tv_usec = 10 * 1000; /* 10 ms */
129 0 : tv.it_interval = tv.it_value;
130 : #ifdef HAVE_SETITIMER
131 0 : setitimer(ITIMER_REAL, &tv, &otv);
132 : #else
133 : ochld = signal(SIGCHLD, SIG_IGN);
134 : pid = fork();
135 : if(pid == -1){
136 : signal(SIGCHLD, ochld != SIG_ERR ? ochld : SIG_DFL);
137 : des_not_rand_data(data, size);
138 : return;
139 : }
140 : if(pid == 0)
141 : pacemaker(&tv.it_interval);
142 : #endif
143 :
144 0 : for(i = 0; i < 4; i++) {
145 0 : for (igdata = 0; igdata < size;) /* igdata++ in sigALRM */
146 0 : counter++;
147 0 : for (j = 0; j < size; j++) /* Only use 2 bits each lap */
148 0 : gdata[j] = (gdata[j]>>2) | (gdata[j]<<6);
149 : }
150 : #ifdef HAVE_SETITIMER
151 0 : setitimer(ITIMER_REAL, &otv, 0);
152 : #else
153 : kill(pid, SIGKILL);
154 : while(waitpid(pid, NULL, 0) != pid);
155 : signal(SIGCHLD, ochld != SIG_ERR ? ochld : SIG_DFL);
156 : #endif
157 0 : signal(SIGALRM, osa != SIG_ERR ? osa : SIG_DFL);
158 :
159 0 : return 1;
160 : #endif
161 : }
162 :
163 : static void
164 0 : timer_cleanup(void)
165 : {
166 0 : }
167 :
168 : static void
169 0 : timer_add(const void *indata, int size, double entropi)
170 : {
171 0 : }
172 :
173 : static int
174 0 : timer_pseudorand(unsigned char *outdata, int size)
175 : {
176 0 : return timer_bytes(outdata, size);
177 : }
178 :
179 : static int
180 0 : timer_status(void)
181 : {
182 : #ifdef WIN32
183 : return 0;
184 : #else
185 0 : return 1;
186 : #endif
187 : }
188 :
189 : const RAND_METHOD hc_rand_timer_method = {
190 : timer_seed,
191 : timer_bytes,
192 : timer_cleanup,
193 : timer_add,
194 : timer_pseudorand,
195 : timer_status
196 : };
197 :
198 : const RAND_METHOD *
199 0 : RAND_timer_method(void)
200 : {
201 0 : return &hc_rand_timer_method;
202 : }
|