exec_elf32.c revision 1.13 1 /* $NetBSD: exec_elf32.c,v 1.13 2016/09/21 16:25:41 christos 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. The name of the author may not be used to endorse or promote products
16 * derived from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 *
29 * <<Id: LICENSE_GC,v 1.1 2001/10/01 23:24:05 cgd Exp>>
30 */
31
32 #include <sys/cdefs.h>
33 #ifndef lint
34 __RCSID("$NetBSD: exec_elf32.c,v 1.13 2016/09/21 16:25:41 christos Exp $");
35 #endif /* not lint */
36
37 #ifndef ELFSIZE
38 #define ELFSIZE 32
39 #endif
40
41 #include <sys/types.h>
42 #include <stdio.h>
43 #include <string.h>
44 #include "extern.h"
45
46 #if defined(NLIST_ELF32) || defined(NLIST_ELF64)
47 #include <sys/exec_elf.h>
48 #endif
49
50 #if (defined(NLIST_ELF32) && (ELFSIZE == 32)) || \
51 (defined(NLIST_ELF64) && (ELFSIZE == 64))
52
53 #define check(off, size) ((off < 0) || (off + size > mappedsize))
54 #define BAD do { rv = -1; goto out; } while (0)
55
56 int
57 ELFNAMEEND(check)(const char *mappedfile, size_t mappedsize)
58 {
59 const Elf_Ehdr *ehdrp;
60 int rv;
61
62 rv = 0;
63
64 if (check(0, sizeof *ehdrp))
65 BAD;
66 ehdrp = (const Elf_Ehdr *)&mappedfile[0];
67
68 if (memcmp(ehdrp->e_ident, ELFMAG, SELFMAG) != 0 ||
69 ehdrp->e_ident[EI_CLASS] != ELFCLASS)
70 BAD;
71
72 switch (ehdrp->e_machine) {
73 ELFDEFNNAME(MACHDEP_ID_CASES)
74
75 default:
76 BAD;
77 }
78
79 out:
80 return (rv);
81 }
82
83 int
84 ELFNAMEEND(findoff)(const char *mappedfile, size_t mappedsize, u_long vmaddr,
85 size_t *fileoffp, u_long text_addr)
86 {
87 const Elf_Ehdr *ehdrp;
88 const Elf_Phdr *phdrp;
89 Elf_Off phdr_off;
90 Elf_Word phdr_size;
91 #if (ELFSIZE == 32)
92 Elf32_Half nphdr, i;
93 #elif (ELFSIZE == 64)
94 Elf64_Word nphdr, i;
95 #endif
96 int rv;
97
98 rv = 0;
99
100 ehdrp = (const Elf_Ehdr *)&mappedfile[0];
101 nphdr = ehdrp->e_phnum;
102 phdr_off = ehdrp->e_phoff;
103 phdr_size = sizeof(Elf_Phdr) * nphdr;
104
105 if (check(0, phdr_off + phdr_size))
106 BAD;
107 phdrp = (const Elf_Phdr *)&mappedfile[phdr_off];
108
109 #define IS_TEXT(p) (p.p_flags & PF_X)
110 #define IS_DATA(p) (p.p_flags & PF_W)
111
112 for (i = 0; i < nphdr; i++) {
113 if ((IS_TEXT(phdrp[i]) || IS_DATA(phdrp[i])) &&
114 phdrp[i].p_vaddr <= vmaddr &&
115 vmaddr < phdrp[i].p_vaddr + phdrp[i].p_filesz) {
116 *fileoffp = vmaddr -
117 phdrp[i].p_vaddr + phdrp[i].p_offset;
118 break;
119 }
120 }
121 if (i == nphdr)
122 BAD;
123
124 out:
125 return (rv);
126 }
127
128 #endif /* include this size of ELF */
129