xref: /netbsd-src/external/bsd/elftoolchain/dist/libelf/gelf_phdr.c (revision 5ac3bc719ce6e70593039505b491894133237d12)
1 /*	$NetBSD: gelf_phdr.c,v 1.5 2024/03/03 17:37:34 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 2006,2008 Joseph Koshy
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  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 
31 #include <gelf.h>
32 #include <libelf.h>
33 #include <limits.h>
34 #include <stdint.h>
35 
36 #include "_libelf.h"
37 
38 __RCSID("$NetBSD: gelf_phdr.c,v 1.5 2024/03/03 17:37:34 christos Exp $");
39 ELFTC_VCSID("Id: gelf_phdr.c 3977 2022-05-01 06:45:34Z jkoshy");
40 
41 Elf32_Phdr *
elf32_getphdr(Elf * e)42 elf32_getphdr(Elf *e)
43 {
44 	return (_libelf_getphdr(e, ELFCLASS32));
45 }
46 
47 Elf64_Phdr *
elf64_getphdr(Elf * e)48 elf64_getphdr(Elf *e)
49 {
50 	return (_libelf_getphdr(e, ELFCLASS64));
51 }
52 
53 GElf_Phdr *
gelf_getphdr(Elf * e,int index,GElf_Phdr * d)54 gelf_getphdr(Elf *e, int index, GElf_Phdr *d)
55 {
56 	int ec;
57 	Elf32_Ehdr *eh32;
58 	Elf64_Ehdr *eh64;
59 	Elf32_Phdr *ep32;
60 	Elf64_Phdr *ep64;
61 	size_t phnum;
62 
63 	if (d == NULL || e == NULL ||
64 	    ((ec = e->e_class) != ELFCLASS32 && ec != ELFCLASS64) ||
65 	    (e->e_kind != ELF_K_ELF) || index < 0 ||
66 	    elf_getphdrnum(e, &phnum) < 0) {
67 		LIBELF_SET_ERROR(ARGUMENT, 0);
68 		return (NULL);
69 	}
70 
71 	if ((size_t)index >= phnum) {
72 		LIBELF_SET_ERROR(ARGUMENT, 0);
73 		return (NULL);
74 	}
75 
76 	if (ec == ELFCLASS32) {
77 		if ((eh32 = _libelf_ehdr(e, ELFCLASS32, 0)) == NULL ||
78 		    ((ep32 = _libelf_getphdr(e, ELFCLASS32)) == NULL))
79 			return (NULL);
80 
81 		ep32 += index;
82 
83 		d->p_type   = ep32->p_type;
84 		d->p_offset = ep32->p_offset;
85 		d->p_vaddr  = (Elf64_Addr) ep32->p_vaddr;
86 		d->p_paddr  = (Elf64_Addr) ep32->p_paddr;
87 		d->p_filesz = (Elf64_Xword) ep32->p_filesz;
88 		d->p_memsz  = (Elf64_Xword) ep32->p_memsz;
89 		d->p_flags  = ep32->p_flags;
90 		d->p_align  = (Elf64_Xword) ep32->p_align;
91 
92 	} else {
93 		if ((eh64 = _libelf_ehdr(e, ELFCLASS64, 0)) == NULL ||
94 		    (ep64 = _libelf_getphdr(e, ELFCLASS64)) == NULL)
95 			return (NULL);
96 
97 		ep64 += index;
98 
99 		*d = *ep64;
100 	}
101 
102 	return (d);
103 }
104 
105 Elf32_Phdr *
elf32_newphdr(Elf * e,size_t count)106 elf32_newphdr(Elf *e, size_t count)
107 {
108 	return (_libelf_newphdr(e, ELFCLASS32, count));
109 }
110 
111 Elf64_Phdr *
elf64_newphdr(Elf * e,size_t count)112 elf64_newphdr(Elf *e, size_t count)
113 {
114 	return (_libelf_newphdr(e, ELFCLASS64, count));
115 }
116 
117 void *
gelf_newphdr(Elf * e,size_t count)118 gelf_newphdr(Elf *e, size_t count)
119 {
120 	if (e == NULL) {
121 		LIBELF_SET_ERROR(ARGUMENT, 0);
122 		return (NULL);
123 	}
124 	return (_libelf_newphdr(e, e->e_class, count));
125 }
126 
127 int
gelf_update_phdr(Elf * e,int ndx,GElf_Phdr * s)128 gelf_update_phdr(Elf *e, int ndx, GElf_Phdr *s)
129 {
130 	int ec;
131 	size_t phnum;
132 	void *ehdr;
133 	Elf32_Phdr *ph32;
134 	Elf64_Phdr *ph64;
135 
136 	if (s == NULL || e == NULL || e->e_kind != ELF_K_ELF ||
137 	    ((ec = e->e_class) != ELFCLASS32 && ec != ELFCLASS64) ||
138 	    elf_getphdrnum(e, &phnum) < 0) {
139 		LIBELF_SET_ERROR(ARGUMENT, 0);
140 		return (0);
141 	}
142 
143 	if (e->e_cmd == ELF_C_READ) {
144 		LIBELF_SET_ERROR(MODE, 0);
145 		return (0);
146 	}
147 
148 	if ((ehdr = _libelf_ehdr(e, ec, 0)) == NULL)
149 		return (0);
150 
151 	if (ndx < 0 || (size_t)ndx > phnum) {
152 		LIBELF_SET_ERROR(ARGUMENT, 0);
153 		return (0);
154 	}
155 
156 	(void) elf_flagphdr(e, ELF_C_SET, ELF_F_DIRTY);
157 
158 	if (ec == ELFCLASS64) {
159 		ph64 = e->e_u.e_elf.e_phdr.e_phdr64 + ndx;
160 		*ph64 = *s;
161 		return (1);
162 	}
163 
164 	ph32 = e->e_u.e_elf.e_phdr.e_phdr32 + ndx;
165 
166 	ph32->p_type     =  s->p_type;
167 	ph32->p_flags    =  s->p_flags;
168 	LIBELF_COPY_U32(ph32, s, p_offset);
169 	LIBELF_COPY_U32(ph32, s, p_vaddr);
170 	LIBELF_COPY_U32(ph32, s, p_paddr);
171 	LIBELF_COPY_U32(ph32, s, p_filesz);
172 	LIBELF_COPY_U32(ph32, s, p_memsz);
173 	LIBELF_COPY_U32(ph32, s, p_align);
174 
175 	return (1);
176 }
177