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 <assert.h>
28 #include <libelf.h>
29
30 #include "_libelf.h"
31
32 ELFTC_VCSID("$Id: libelf_extended.c 3712 2019-03-16 22:23:34Z jkoshy $");
33
34 /*
35 * Retrieve section #0, allocating a new section if needed.
36 */
37 static Elf_Scn *
_libelf_getscn0(Elf * e)38 _libelf_getscn0(Elf *e)
39 {
40 Elf_Scn *s;
41
42 if ((s = RB_MIN(scntree, &e->e_u.e_elf.e_scn)) != NULL)
43 return (s);
44
45 return (_libelf_allocate_scn(e, (size_t) SHN_UNDEF));
46 }
47
48 int
_libelf_setshnum(Elf * e,void * eh,int ec,size_t shnum)49 _libelf_setshnum(Elf *e, void *eh, int ec, size_t shnum)
50 {
51 Elf_Scn *scn;
52
53 if (shnum >= SHN_LORESERVE) {
54 if ((scn = _libelf_getscn0(e)) == NULL)
55 return (0);
56
57 assert(scn->s_ndx == SHN_UNDEF);
58
59 if (ec == ELFCLASS32)
60 scn->s_shdr.s_shdr32.sh_size = (Elf32_Word) shnum;
61 else
62 scn->s_shdr.s_shdr64.sh_size = shnum;
63
64 (void) elf_flagshdr(scn, ELF_C_SET, ELF_F_DIRTY);
65
66 shnum = 0;
67 }
68
69 if (ec == ELFCLASS32)
70 ((Elf32_Ehdr *) eh)->e_shnum = shnum & 0xFFFFU;
71 else
72 ((Elf64_Ehdr *) eh)->e_shnum = shnum & 0xFFFFU;
73
74
75 return (1);
76 }
77
78 int
_libelf_setshstrndx(Elf * e,void * eh,int ec,size_t shstrndx)79 _libelf_setshstrndx(Elf *e, void *eh, int ec, size_t shstrndx)
80 {
81 Elf_Scn *scn;
82
83 if (shstrndx >= SHN_LORESERVE) {
84 if ((scn = _libelf_getscn0(e)) == NULL)
85 return (0);
86
87 assert(scn->s_ndx == SHN_UNDEF);
88
89 if (ec == ELFCLASS32)
90 scn->s_shdr.s_shdr32.sh_link = (Elf32_Word) shstrndx;
91 else
92 scn->s_shdr.s_shdr64.sh_link = (Elf64_Word) shstrndx;
93
94 (void) elf_flagshdr(scn, ELF_C_SET, ELF_F_DIRTY);
95
96 shstrndx = SHN_XINDEX;
97 }
98
99 if (ec == ELFCLASS32)
100 ((Elf32_Ehdr *) eh)->e_shstrndx = shstrndx & 0xFFFFU;
101 else
102 ((Elf64_Ehdr *) eh)->e_shstrndx = shstrndx & 0xFFFFU;
103
104 return (1);
105 }
106
107 int
_libelf_setphnum(Elf * e,void * eh,int ec,size_t phnum)108 _libelf_setphnum(Elf *e, void *eh, int ec, size_t phnum)
109 {
110 Elf_Scn *scn;
111
112 if (phnum >= PN_XNUM) {
113 if ((scn = _libelf_getscn0(e)) == NULL)
114 return (0);
115
116 assert(scn->s_ndx == SHN_UNDEF);
117
118 if (ec == ELFCLASS32)
119 scn->s_shdr.s_shdr32.sh_info = (Elf32_Word) phnum;
120 else
121 scn->s_shdr.s_shdr64.sh_info = (Elf64_Word) phnum;
122
123 (void) elf_flagshdr(scn, ELF_C_SET, ELF_F_DIRTY);
124
125 phnum = PN_XNUM;
126 }
127
128 if (ec == ELFCLASS32)
129 ((Elf32_Ehdr *) eh)->e_phnum = phnum & 0xFFFFU;
130 else
131 ((Elf64_Ehdr *) eh)->e_phnum = phnum & 0xFFFFU;
132
133 return (1);
134 }
135