1 /*-
2  * Copyright (c) 2006,2008 Joseph Koshy
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <gelf.h>
28 #include <libelf.h>
29 #include <limits.h>
30 #include <stdint.h>
31 
32 #include "_libelf.h"
33 
34 ELFTC_VCSID("$Id: gelf_phdr.c 3177 2015-03-30 18:19:41Z emaste $");
35 
36 Elf32_Phdr *
37 elf32_getphdr(Elf *e)
38 {
39 	return (_libelf_getphdr(e, ELFCLASS32));
40 }
41 
42 Elf64_Phdr *
43 elf64_getphdr(Elf *e)
44 {
45 	return (_libelf_getphdr(e, ELFCLASS64));
46 }
47 
48 GElf_Phdr *
49 gelf_getphdr(Elf *e, int index, GElf_Phdr *d)
50 {
51 	int ec;
52 	Elf32_Ehdr *eh32;
53 	Elf64_Ehdr *eh64;
54 	Elf32_Phdr *ep32;
55 	Elf64_Phdr *ep64;
56 
57 	if (d == NULL || e == NULL ||
58 	    ((ec = e->e_class) != ELFCLASS32 && ec != ELFCLASS64) ||
59 	    (e->e_kind != ELF_K_ELF) || index < 0) {
60 		LIBELF_SET_ERROR(ARGUMENT, 0);
61 		return (NULL);
62 	}
63 
64 	if (ec == ELFCLASS32) {
65 		if ((eh32 = _libelf_ehdr(e, ELFCLASS32, 0)) == NULL ||
66 		    ((ep32 = _libelf_getphdr(e, ELFCLASS32)) == NULL))
67 			return (NULL);
68 
69 		if (index >= eh32->e_phnum) {
70 			LIBELF_SET_ERROR(ARGUMENT, 0);
71 			return (NULL);
72 		}
73 
74 		ep32 += index;
75 
76 		d->p_type   = ep32->p_type;
77 		d->p_offset = ep32->p_offset;
78 		d->p_vaddr  = (Elf64_Addr) ep32->p_vaddr;
79 		d->p_paddr  = (Elf64_Addr) ep32->p_paddr;
80 		d->p_filesz = (Elf64_Xword) ep32->p_filesz;
81 		d->p_memsz  = (Elf64_Xword) ep32->p_memsz;
82 		d->p_flags  = ep32->p_flags;
83 		d->p_align  = (Elf64_Xword) ep32->p_align;
84 
85 	} else {
86 		if ((eh64 = _libelf_ehdr(e, ELFCLASS64, 0)) == NULL ||
87 		    (ep64 = _libelf_getphdr(e, ELFCLASS64)) == NULL)
88 			return (NULL);
89 
90 		if (index >= eh64->e_phnum) {
91 			LIBELF_SET_ERROR(ARGUMENT, 0);
92 			return (NULL);
93 		}
94 
95 		ep64 += index;
96 
97 		*d = *ep64;
98 	}
99 
100 	return (d);
101 }
102 
103 Elf32_Phdr *
104 elf32_newphdr(Elf *e, size_t count)
105 {
106 	return (_libelf_newphdr(e, ELFCLASS32, count));
107 }
108 
109 Elf64_Phdr *
110 elf64_newphdr(Elf *e, size_t count)
111 {
112 	return (_libelf_newphdr(e, ELFCLASS64, count));
113 }
114 
115 void *
116 gelf_newphdr(Elf *e, size_t count)
117 {
118 	if (e == NULL) {
119 		LIBELF_SET_ERROR(ARGUMENT, 0);
120 		return (NULL);
121 	}
122 	return (_libelf_newphdr(e, e->e_class, count));
123 }
124 
125 int
126 gelf_update_phdr(Elf *e, int ndx, GElf_Phdr *s)
127 {
128 	int ec, phnum;
129 	void *ehdr;
130 	Elf32_Phdr *ph32;
131 	Elf64_Phdr *ph64;
132 
133 	if (s == NULL || e == NULL || e->e_kind != ELF_K_ELF ||
134 	    ((ec = e->e_class) != ELFCLASS32 && ec != ELFCLASS64)) {
135 		LIBELF_SET_ERROR(ARGUMENT, 0);
136 		return (0);
137 	}
138 
139 	if (e->e_cmd == ELF_C_READ) {
140 		LIBELF_SET_ERROR(MODE, 0);
141 		return (0);
142 	}
143 
144 	if ((ehdr = _libelf_ehdr(e, ec, 0)) == NULL)
145 		return (0);
146 
147 	if (ec == ELFCLASS32)
148 		phnum = ((Elf32_Ehdr *) ehdr)->e_phnum;
149 	else
150 		phnum = ((Elf64_Ehdr *) ehdr)->e_phnum;
151 
152 	if (ndx < 0 || ndx > phnum) {
153 		LIBELF_SET_ERROR(ARGUMENT, 0);
154 		return (0);
155 	}
156 
157 	(void) elf_flagphdr(e, ELF_C_SET, ELF_F_DIRTY);
158 
159 	if (ec == ELFCLASS64) {
160 		ph64 = e->e_u.e_elf.e_phdr.e_phdr64 + ndx;
161 		*ph64 = *s;
162 		return (1);
163 	}
164 
165 	ph32 = e->e_u.e_elf.e_phdr.e_phdr32 + ndx;
166 
167 	ph32->p_type     =  s->p_type;
168 	ph32->p_flags    =  s->p_flags;
169 	LIBELF_COPY_U32(ph32, s, p_offset);
170 	LIBELF_COPY_U32(ph32, s, p_vaddr);
171 	LIBELF_COPY_U32(ph32, s, p_paddr);
172 	LIBELF_COPY_U32(ph32, s, p_filesz);
173 	LIBELF_COPY_U32(ph32, s, p_memsz);
174 	LIBELF_COPY_U32(ph32, s, p_align);
175 
176 	return (1);
177 }
178