1 /*-
2 * Copyright (c) 2006 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 /*
28 * Internal APIs
29 */
30
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33
34 #include <sys/errno.h>
35
36 #include <assert.h>
37 #include <libelf.h>
38 #include <stdlib.h>
39 #include <string.h>
40
41 #include "_libelf.h"
42
43 Elf *
_libelf_allocate_elf(void)44 _libelf_allocate_elf(void)
45 {
46 Elf *e;
47
48 if ((e = malloc(sizeof(*e))) == NULL) {
49 LIBELF_SET_ERROR(RESOURCE, errno);
50 return NULL;
51 }
52
53 e->e_activations = 1;
54 e->e_arhdr = NULL;
55 e->e_byteorder = ELFDATANONE;
56 e->e_class = ELFCLASSNONE;
57 e->e_cmd = ELF_C_NULL;
58 e->e_fd = -1;
59 e->e_flags = 0;
60 e->e_kind = ELF_K_NONE;
61 e->e_parent = NULL;
62 e->e_rawfile = NULL;
63 e->e_rawsize = 0;
64 e->e_version = LIBELF_PRIVATE(version);
65
66 (void) memset(&e->e_u, 0, sizeof(e->e_u));
67
68 return (e);
69 }
70
71 void
_libelf_init_elf(Elf * e,Elf_Kind kind)72 _libelf_init_elf(Elf *e, Elf_Kind kind)
73 {
74 assert(e != NULL);
75 assert(e->e_kind == ELF_K_NONE);
76
77 e->e_kind = kind;
78
79 switch (kind) {
80 case ELF_K_ELF:
81 STAILQ_INIT(&e->e_u.e_elf.e_scn);
82 break;
83 default:
84 break;
85 }
86 }
87
88 #define FREE(P) do { \
89 if (P) \
90 free(P); \
91 } while (0)
92
93
94 Elf *
_libelf_release_elf(Elf * e)95 _libelf_release_elf(Elf *e)
96 {
97 switch (e->e_kind) {
98 case ELF_K_AR:
99 FREE(e->e_u.e_ar.e_symtab);
100 break;
101
102 case ELF_K_ELF:
103 switch (e->e_class) {
104 case ELFCLASS32:
105 FREE(e->e_u.e_elf.e_ehdr.e_ehdr32);
106 FREE(e->e_u.e_elf.e_phdr.e_phdr32);
107 break;
108 case ELFCLASS64:
109 FREE(e->e_u.e_elf.e_ehdr.e_ehdr64);
110 FREE(e->e_u.e_elf.e_phdr.e_phdr64);
111 break;
112 }
113
114 assert(STAILQ_EMPTY(&e->e_u.e_elf.e_scn));
115
116 if (e->e_arhdr) {
117 FREE(e->e_arhdr->ar_name);
118 FREE(e->e_arhdr->ar_rawname);
119 free(e->e_arhdr);
120 }
121
122 break;
123
124 default:
125 break;
126 }
127
128 free(e);
129
130 return (NULL);
131 }
132
133 Elf_Data *
_libelf_allocate_data(Elf_Scn * s)134 _libelf_allocate_data(Elf_Scn *s)
135 {
136 Elf_Data *d;
137
138 if ((d = calloc((size_t) 1, sizeof(Elf_Data))) == NULL) {
139 LIBELF_SET_ERROR(RESOURCE, 0);
140 return (NULL);
141 }
142
143 d->d_scn = s;
144
145 return (d);
146 }
147
148 Elf_Data *
_libelf_release_data(Elf_Data * d)149 _libelf_release_data(Elf_Data *d)
150 {
151
152 if (d->d_flags & LIBELF_F_MALLOCED)
153 free(d->d_buf);
154
155 free(d);
156
157 return (NULL);
158 }
159
160 Elf_Scn *
_libelf_allocate_scn(Elf * e,size_t ndx)161 _libelf_allocate_scn(Elf *e, size_t ndx)
162 {
163 Elf_Scn *s;
164
165 if ((s = calloc((size_t) 1, sizeof(Elf_Scn))) == NULL) {
166 LIBELF_SET_ERROR(RESOURCE, errno);
167 return (NULL);
168 }
169
170 s->s_elf = e;
171 s->s_ndx = ndx;
172
173 STAILQ_INIT(&s->s_data);
174 STAILQ_INIT(&s->s_rawdata);
175
176 STAILQ_INSERT_TAIL(&e->e_u.e_elf.e_scn, s, s_next);
177
178 return (s);
179 }
180
181 Elf_Scn *
_libelf_release_scn(Elf_Scn * s)182 _libelf_release_scn(Elf_Scn *s)
183 {
184 Elf *e;
185 Elf_Data *d, *td;
186
187 assert(s != NULL);
188
189 STAILQ_FOREACH_SAFE(d, &s->s_data, d_next, td) {
190 STAILQ_REMOVE(&s->s_data, d, _Elf_Data, d_next);
191 d = _libelf_release_data(d);
192 }
193
194 STAILQ_FOREACH_SAFE(d, &s->s_rawdata, d_next, td) {
195 assert((d->d_flags & LIBELF_F_MALLOCED) == 0);
196 STAILQ_REMOVE(&s->s_rawdata, d, _Elf_Data, d_next);
197 d = _libelf_release_data(d);
198 }
199
200 e = s->s_elf;
201
202 assert(e != NULL);
203
204 STAILQ_REMOVE(&e->e_u.e_elf.e_scn, s, _Elf_Scn, s_next);
205
206 free(s);
207
208 return (NULL);
209 }
210