xref: /openbsd-src/sys/kern/exec_conf.c (revision 91f110e064cd7c194e59e019b83bb7496c1c84d4)
1 /*	$OpenBSD: exec_conf.c,v 1.31 2013/10/17 10:38:28 deraadt Exp $	*/
2 /*	$NetBSD: exec_conf.c,v 1.16 1995/12/09 05:34:47 cgd Exp $	*/
3 
4 /*
5  * Copyright (c) 1993, 1994 Christopher G. Demetriou
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
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  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *      This product includes software developed by Christopher G. Demetriou.
19  * 4. The name of the author may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <sys/param.h>
35 #include <sys/exec.h>
36 #include <sys/exec_script.h>
37 
38 #if defined(_KERN_DO_ELF) || defined(_KERN_DO_ELF64)
39 #include <sys/exec_elf.h>
40 #endif
41 
42 #ifdef COMPAT_LINUX
43 #include <compat/linux/linux_exec.h>
44 #endif
45 
46 extern struct emul emul_native, emul_elf32, emul_elf64, emul_linux_elf;
47 
48 struct execsw execsw[] = {
49 	{ EXEC_SCRIPT_HDRSZ, exec_script_makecmds, &emul_native, },	/* shell scripts */
50 #ifdef _KERN_DO_ELF
51 	{ sizeof(Elf32_Ehdr), exec_elf32_makecmds, &emul_native },	/* elf binaries */
52 #endif
53 #ifdef _KERN_DO_ELF64
54 	{ sizeof(Elf64_Ehdr), exec_elf64_makecmds, &emul_native },	/* elf binaries */
55 #endif /* ELF64 */
56 #ifdef COMPAT_LINUX
57 	{ sizeof(Elf32_Ehdr), exec_linux_elf32_makecmds, &emul_linux_elf },
58 #endif
59 #ifdef LKM
60 	{ 0, NULL, NULL },				/* entries for LKMs */
61 	{ 0, NULL, NULL },
62 	{ 0, NULL, NULL },
63 	{ 0, NULL, NULL },
64 	{ 0, NULL, NULL },
65 #endif
66 };
67 int nexecs = (sizeof execsw / sizeof(*execsw));
68 int exec_maxhdrsz;
69 
70 void	init_exec(void);
71 
72 void
73 init_exec(void)
74 {
75 	int i;
76 
77 	/*
78 	 * figure out the maximum size of an exec header.
79 	 * XXX should be able to keep LKM code from modifying exec switch
80 	 * when we're still using it, but...
81 	 */
82 	for (i = 0; i < nexecs; i++)
83 		if (execsw[i].es_check != NULL &&
84 		    execsw[i].es_hdrsz > exec_maxhdrsz)
85 			exec_maxhdrsz = execsw[i].es_hdrsz;
86 }
87