xref: /openbsd/lib/libc/crypt/arc4random.h (revision e5dd7070)
1 /*	$OpenBSD: arc4random.h,v 1.4 2015/01/15 06:57:18 deraadt Exp $	*/
2 
3 /*
4  * Copyright (c) 1996, David Mazieres <dm@uun.org>
5  * Copyright (c) 2008, Damien Miller <djm@openbsd.org>
6  * Copyright (c) 2013, Markus Friedl <markus@openbsd.org>
7  * Copyright (c) 2014, Theo de Raadt <deraadt@openbsd.org>
8  *
9  * Permission to use, copy, modify, and distribute this software for any
10  * purpose with or without fee is hereby granted, provided that the above
11  * copyright notice and this permission notice appear in all copies.
12  *
13  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
14  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
15  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
16  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
17  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
18  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
19  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
20  */
21 
22 /*
23  * Stub functions for portability.
24  */
25 #include <sys/mman.h>
26 
27 #include <signal.h>
28 
29 #include "thread_private.h"
30 
31 static inline void
32 _getentropy_fail(void)
33 {
34 	raise(SIGKILL);
35 }
36 
37 static inline int
38 _rs_allocate(struct _rs **rsp, struct _rsx **rsxp)
39 {
40 	struct {
41 		struct _rs rs;
42 		struct _rsx rsx;
43 	} *p;
44 
45 	if ((p = mmap(NULL, sizeof(*p), PROT_READ|PROT_WRITE,
46 	    MAP_ANON|MAP_PRIVATE, -1, 0)) == MAP_FAILED)
47 		return (-1);
48 	if (minherit(p, sizeof(*p), MAP_INHERIT_ZERO) == -1) {
49 		munmap(p, sizeof(*p));
50 		return (-1);
51 	}
52 
53 	*rsp = &p->rs;
54 	*rsxp = &p->rsx;
55 	return (0);
56 }
57 
58 static inline void
59 _rs_forkdetect(void)
60 {
61 }
62