xref: /netbsd-src/usr.sbin/mdsetimage/exec_elf32.c (revision 3b01aba77a7a698587faaae455bbfe740923c1f5)
1 /* $NetBSD: exec_elf32.c,v 1.8 2000/06/14 17:26:15 cgd Exp $ */
2 
3 /*
4  * Copyright (c) 1996 Christopher G. Demetriou
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *          This product includes software developed for the
18  *          NetBSD Project.  See http://www.netbsd.org/ for
19  *          information about NetBSD.
20  * 4. The name of the author may not be used to endorse or promote products
21  *    derived from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  *
34  * <<Id: LICENSE,v 1.2 2000/06/14 15:57:33 cgd Exp>>
35  */
36 
37 #include <sys/cdefs.h>
38 #ifndef lint
39 __RCSID("$NetBSD: exec_elf32.c,v 1.8 2000/06/14 17:26:15 cgd Exp $");
40 #endif /* not lint */
41 
42 #ifndef ELFSIZE
43 #define	ELFSIZE		32
44 #endif
45 
46 #include <sys/types.h>
47 #include <stdio.h>
48 #include <string.h>
49 #include "extern.h"
50 
51 #if defined(NLIST_ELF32) || defined(NLIST_ELF64)
52 #include <sys/exec_elf.h>
53 #endif
54 
55 #if (defined(NLIST_ELF32) && (ELFSIZE == 32)) || \
56     (defined(NLIST_ELF64) && (ELFSIZE == 64))
57 
58 #define	check(off, size)	((off < 0) || (off + size > mappedsize))
59 #define	BAD			do { rv = -1; goto out; } while (0)
60 
61 int
62 ELFNAMEEND(check)(mappedfile, mappedsize)
63 	const char *mappedfile;
64 	size_t mappedsize;
65 {
66 	Elf_Ehdr *ehdrp;
67 	int rv;
68 
69 	rv = 0;
70 
71 	if (check(0, sizeof *ehdrp))
72 		BAD;
73 	ehdrp = (Elf_Ehdr *)&mappedfile[0];
74 
75 	if (memcmp(ehdrp->e_ident, ELFMAG, SELFMAG) != 0 ||
76 	    ehdrp->e_ident[EI_CLASS] != ELFCLASS)
77 		BAD;
78 
79 	switch (ehdrp->e_machine) {
80 	ELFDEFNNAME(MACHDEP_ID_CASES)
81 
82 	default:
83 		BAD;
84 	}
85 
86 out:
87 	return (rv);
88 }
89 
90 int
91 ELFNAMEEND(findoff)(mappedfile, mappedsize, vmaddr, fileoffp)
92 	const char *mappedfile;
93 	size_t mappedsize, *fileoffp;
94 	u_long vmaddr;
95 {
96 	Elf_Ehdr *ehdrp;
97 	Elf_Shdr *shdrp;
98 	Elf_Off shdr_off;
99 	Elf_Word shdr_size;
100 #if (ELFSIZE == 32)
101 	Elf32_Half nshdr, i;
102 #elif (ELFSIZE == 64)
103 	Elf64_Half nshdr, i;
104 #endif
105 	int rv;
106 
107 	rv = 0;
108 
109 	ehdrp = (Elf_Ehdr *)&mappedfile[0];
110 	nshdr = ehdrp->e_shnum;
111 	shdr_off = ehdrp->e_shoff;
112 	shdr_size = ehdrp->e_shentsize * nshdr;
113 
114 	if (check(shdr_off, shdr_size) ||
115 	    (sizeof *shdrp != ehdrp->e_shentsize))
116 		BAD;
117 	shdrp = (Elf_Shdr *)&mappedfile[shdr_off];
118 
119 	for (i = 0; i < nshdr; i++) {
120 		if (shdrp[i].sh_addr <= vmaddr &&
121 		    vmaddr < (shdrp[i].sh_addr + shdrp[i].sh_size)) {
122 			*fileoffp = vmaddr -
123 			    shdrp[i].sh_addr + shdrp[i].sh_offset;
124 			break;
125 		}
126 	}
127 	if (i == nshdr)
128 		BAD;
129 
130 out:
131 	return (rv);
132 }
133 
134 #endif /* include this size of ELF */
135