2 * Copyright (c) 2006,2008,2011 Joseph Koshy
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
34 ELFTC_VCSID("$Id: elf_data.c 3009 2014-03-23 01:49:59Z jkoshy $");
37 elf_getdata(Elf_Scn *s, Elf_Data *ed)
41 int elfclass, elftype;
42 size_t count, fsz, msz;
43 struct _Libelf_Data *d;
44 uint64_t sh_align, sh_offset, sh_size;
45 int (*xlate)(unsigned char *_d, size_t _dsz, unsigned char *_s,
46 size_t _c, int _swap);
48 d = (struct _Libelf_Data *) ed;
50 if (s == NULL || (e = s->s_elf) == NULL ||
51 (d != NULL && s != d->d_scn)) {
52 LIBELF_SET_ERROR(ARGUMENT, 0);
56 assert(e->e_kind == ELF_K_ELF);
58 if (d == NULL && (d = STAILQ_FIRST(&s->s_data)) != NULL)
62 return (&STAILQ_NEXT(d, d_next)->d_data);
64 if (e->e_rawfile == NULL) {
66 * In the ELF_C_WRITE case, there is no source that
67 * can provide data for the section.
69 LIBELF_SET_ERROR(ARGUMENT, 0);
73 elfclass = e->e_class;
75 assert(elfclass == ELFCLASS32 || elfclass == ELFCLASS64);
77 if (elfclass == ELFCLASS32) {
78 sh_type = s->s_shdr.s_shdr32.sh_type;
79 sh_offset = (uint64_t) s->s_shdr.s_shdr32.sh_offset;
80 sh_size = (uint64_t) s->s_shdr.s_shdr32.sh_size;
81 sh_align = (uint64_t) s->s_shdr.s_shdr32.sh_addralign;
83 sh_type = s->s_shdr.s_shdr64.sh_type;
84 sh_offset = s->s_shdr.s_shdr64.sh_offset;
85 sh_size = s->s_shdr.s_shdr64.sh_size;
86 sh_align = s->s_shdr.s_shdr64.sh_addralign;
89 if (sh_type == SHT_NULL) {
90 LIBELF_SET_ERROR(SECTION, 0);
94 if ((elftype = _libelf_xlate_shtype(sh_type)) < ELF_T_FIRST ||
95 elftype > ELF_T_LAST || (sh_type != SHT_NOBITS &&
96 sh_offset + sh_size > (uint64_t) e->e_rawsize)) {
97 LIBELF_SET_ERROR(SECTION, 0);
101 if ((fsz = (elfclass == ELFCLASS32 ? elf32_fsize : elf64_fsize)
102 (elftype, (size_t) 1, e->e_version)) == 0) {
103 LIBELF_SET_ERROR(UNIMPL, 0);
108 LIBELF_SET_ERROR(SECTION, 0);
112 if (sh_size / fsz > SIZE_MAX) {
113 LIBELF_SET_ERROR(RANGE, 0);
117 count = (size_t) (sh_size / fsz);
119 msz = _libelf_msize(elftype, elfclass, e->e_version);
121 if (count > 0 && msz > SIZE_MAX / count) {
122 LIBELF_SET_ERROR(RANGE, 0);
127 assert(count <= SIZE_MAX);
128 assert(msz * count <= SIZE_MAX);
130 if ((d = _libelf_allocate_data(s)) == NULL)
133 d->d_data.d_buf = NULL;
135 d->d_data.d_align = sh_align;
136 d->d_data.d_size = msz * count;
137 d->d_data.d_type = elftype;
138 d->d_data.d_version = e->e_version;
140 if (sh_type == SHT_NOBITS || sh_size == 0) {
141 STAILQ_INSERT_TAIL(&s->s_data, d, d_next);
145 if ((d->d_data.d_buf = malloc(msz * count)) == NULL) {
146 (void) _libelf_release_data(d);
147 LIBELF_SET_ERROR(RESOURCE, 0);
151 d->d_flags |= LIBELF_F_DATA_MALLOCED;
153 xlate = _libelf_get_translator(elftype, ELF_TOMEMORY, elfclass);
154 if (!(*xlate)(d->d_data.d_buf, (size_t) d->d_data.d_size,
155 e->e_rawfile + sh_offset, count,
156 e->e_byteorder != LIBELF_PRIVATE(byteorder))) {
157 _libelf_release_data(d);
158 LIBELF_SET_ERROR(DATA, 0);
162 STAILQ_INSERT_TAIL(&s->s_data, d, d_next);
168 elf_newdata(Elf_Scn *s)
171 struct _Libelf_Data *d;
173 if (s == NULL || (e = s->s_elf) == NULL) {
174 LIBELF_SET_ERROR(ARGUMENT, 0);
178 assert(e->e_kind == ELF_K_ELF);
181 * elf_newdata() has to append a data descriptor, so
182 * bring in existing section data if not already present.
184 if (e->e_rawfile && s->s_size > 0 && STAILQ_EMPTY(&s->s_data))
185 if (elf_getdata(s, NULL) == NULL)
188 if ((d = _libelf_allocate_data(s)) == NULL)
191 STAILQ_INSERT_TAIL(&s->s_data, d, d_next);
193 d->d_data.d_align = 1;
194 d->d_data.d_buf = NULL;
195 d->d_data.d_off = (uint64_t) ~0;
196 d->d_data.d_size = 0;
197 d->d_data.d_type = ELF_T_BYTE;
198 d->d_data.d_version = LIBELF_PRIVATE(version);
200 (void) elf_flagscn(s, ELF_C_SET, ELF_F_DIRTY);
206 * Retrieve a data descriptor for raw (untranslated) data for section
211 elf_rawdata(Elf_Scn *s, Elf_Data *ed)
216 struct _Libelf_Data *d;
217 uint64_t sh_align, sh_offset, sh_size;
219 if (s == NULL || (e = s->s_elf) == NULL || e->e_rawfile == NULL) {
220 LIBELF_SET_ERROR(ARGUMENT, 0);
224 assert(e->e_kind == ELF_K_ELF);
226 d = (struct _Libelf_Data *) ed;
228 if (d == NULL && (d = STAILQ_FIRST(&s->s_rawdata)) != NULL)
232 return (&STAILQ_NEXT(d, d_next)->d_data);
234 elf_class = e->e_class;
236 assert(elf_class == ELFCLASS32 || elf_class == ELFCLASS64);
238 if (elf_class == ELFCLASS32) {
239 sh_type = s->s_shdr.s_shdr32.sh_type;
240 sh_offset = (uint64_t) s->s_shdr.s_shdr32.sh_offset;
241 sh_size = (uint64_t) s->s_shdr.s_shdr32.sh_size;
242 sh_align = (uint64_t) s->s_shdr.s_shdr32.sh_addralign;
244 sh_type = s->s_shdr.s_shdr64.sh_type;
245 sh_offset = s->s_shdr.s_shdr64.sh_offset;
246 sh_size = s->s_shdr.s_shdr64.sh_size;
247 sh_align = s->s_shdr.s_shdr64.sh_addralign;
250 if (sh_type == SHT_NULL) {
251 LIBELF_SET_ERROR(SECTION, 0);
255 if ((d = _libelf_allocate_data(s)) == NULL)
258 d->d_data.d_buf = (sh_type == SHT_NOBITS || sh_size == 0) ? NULL :
259 e->e_rawfile + sh_offset;
261 d->d_data.d_align = sh_align;
262 d->d_data.d_size = sh_size;
263 d->d_data.d_type = ELF_T_BYTE;
264 d->d_data.d_version = e->e_version;
266 STAILQ_INSERT_TAIL(&s->s_rawdata, d, d_next);