2 * Copyright (C) 2015 John Crispin <blogic@openwrt.org>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU Lesser General Public License version 2.1
6 * as published by the Free Software Foundation
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
27 #include <libubox/utils.h>
31 struct avl_tree libraries
;
32 static LIST_HEAD(library_paths
);
34 void alloc_library_path(const char *path
)
36 struct library_path
*p
;
39 p
= calloc_a(sizeof(*p
),
40 &_path
, strlen(path
) + 1);
44 p
->path
= strcpy(_path
, path
);
46 list_add_tail(&p
->list
, &library_paths
);
47 DEBUG("adding ld.so path %s\n", path
);
50 static void alloc_library(const char *path
, const char *name
)
55 l
= calloc_a(sizeof(*l
),
56 &_path
, strlen(path
) + 1,
57 &_name
, strlen(name
) + 1);
61 l
->avl
.key
= l
->name
= strcpy(_name
, name
);
62 l
->path
= strcpy(_path
, path
);
64 avl_insert(&libraries
, &l
->avl
);
65 DEBUG("adding library %s/%s\n", path
, name
);
68 static int elf_open(char **dir
, char *file
)
70 struct library_path
*p
;
76 list_for_each_entry(p
, &library_paths
, list
) {
78 snprintf(path
, sizeof(path
), "%s/%s", p
->path
, file
);
80 strncpy(path
, file
, sizeof(path
));
81 fd
= open(path
, O_RDONLY
);
89 fd
= open(file
, O_RDONLY
);
94 char* find_lib(char *file
)
97 static char path
[256];
100 l
= avl_find_element(&libraries
, file
, l
, avl
);
105 if (strstr(p
, "local"))
108 snprintf(path
, sizeof(path
), "%s/%s", p
, file
);
113 static int elf64_find_section(char *map
, unsigned int type
, unsigned int *offset
, unsigned int *size
, unsigned int *vaddr
)
119 e
= (Elf64_Ehdr
*) map
;
120 ph
= (Elf64_Phdr
*) (map
+ e
->e_phoff
);
122 for (i
= 0; i
< e
->e_phnum
; i
++) {
123 if (ph
[i
].p_type
== type
) {
124 *offset
= ph
[i
].p_offset
;
126 *size
= ph
[i
].p_filesz
;
128 *vaddr
= ph
[i
].p_vaddr
;
136 static int elf32_find_section(char *map
, unsigned int type
, unsigned int *offset
, unsigned int *size
, unsigned int *vaddr
)
142 e
= (Elf32_Ehdr
*) map
;
143 ph
= (Elf32_Phdr
*) (map
+ e
->e_phoff
);
145 for (i
= 0; i
< e
->e_phnum
; i
++) {
146 if (ph
[i
].p_type
== type
) {
147 *offset
= ph
[i
].p_offset
;
149 *size
= ph
[i
].p_filesz
;
151 *vaddr
= ph
[i
].p_vaddr
;
159 static int elf_find_section(char *map
, unsigned int type
, unsigned int *offset
, unsigned int *size
, unsigned int *vaddr
)
161 int clazz
= map
[EI_CLASS
];
163 if (clazz
== ELFCLASS32
)
164 return elf32_find_section(map
, type
, offset
, size
, vaddr
);
165 else if (clazz
== ELFCLASS64
)
166 return elf64_find_section(map
, type
, offset
, size
, vaddr
);
168 ERROR("unknown elf format %d\n", clazz
);
173 static int elf32_scan_dynamic(char *map
, int dyn_offset
, int dyn_size
, int load_offset
)
175 Elf32_Dyn
*dynamic
= (Elf32_Dyn
*) (map
+ dyn_offset
);
178 while ((void *) dynamic
< (void *) (map
+ dyn_offset
+ dyn_size
)) {
179 Elf32_Dyn
*curr
= dynamic
;
182 if (curr
->d_tag
!= DT_STRTAB
)
185 strtab
= map
+ (curr
->d_un
.d_val
- load_offset
);
192 dynamic
= (Elf32_Dyn
*) (map
+ dyn_offset
);
193 while ((void *) dynamic
< (void *) (map
+ dyn_offset
+ dyn_size
)) {
194 Elf32_Dyn
*curr
= dynamic
;
197 if (curr
->d_tag
!= DT_NEEDED
)
200 if (elf_load_deps(&strtab
[curr
->d_un
.d_val
]))
207 static int elf64_scan_dynamic(char *map
, int dyn_offset
, int dyn_size
, int load_offset
)
209 Elf64_Dyn
*dynamic
= (Elf64_Dyn
*) (map
+ dyn_offset
);
212 while ((void *) dynamic
< (void *) (map
+ dyn_offset
+ dyn_size
)) {
213 Elf64_Dyn
*curr
= dynamic
;
216 if (curr
->d_tag
!= DT_STRTAB
)
219 strtab
= map
+ (curr
->d_un
.d_val
- load_offset
);
226 dynamic
= (Elf64_Dyn
*) (map
+ dyn_offset
);
227 while ((void *) dynamic
< (void *) (map
+ dyn_offset
+ dyn_size
)) {
228 Elf64_Dyn
*curr
= dynamic
;
231 if (curr
->d_tag
!= DT_NEEDED
)
234 if (elf_load_deps(&strtab
[curr
->d_un
.d_val
]))
241 int elf_load_deps(char *library
)
243 unsigned int dyn_offset
, dyn_size
;
244 unsigned int load_offset
, load_vaddr
;
246 char *map
= NULL
, *dir
= NULL
;
247 int clazz
, fd
, ret
= -1;
249 if (avl_find(&libraries
, library
))
252 fd
= elf_open(&dir
, library
);
255 ERROR("failed to open %s\n", library
);
259 if (fstat(fd
, &s
) == -1) {
260 ERROR("failed to stat %s\n", library
);
265 map
= mmap(NULL
, s
.st_size
, PROT_READ
, MAP_PRIVATE
, fd
, 0);
266 if (map
== MAP_FAILED
) {
267 ERROR("failed to mmap %s\n", library
);
272 if (elf_find_section(map
, PT_LOAD
, &load_offset
, NULL
, &load_vaddr
)) {
273 ERROR("failed to load the .load section from %s\n", library
);
278 if (elf_find_section(map
, PT_DYNAMIC
, &dyn_offset
, &dyn_size
, NULL
)) {
279 ERROR("failed to load the .dynamic section from %s\n", library
);
285 alloc_library(dir
, library
);
287 char *elf
= strdup(library
);
289 alloc_library(dirname(elf
), basename(library
));
292 clazz
= map
[EI_CLASS
];
294 if (clazz
== ELFCLASS32
)
295 ret
= elf32_scan_dynamic(map
, dyn_offset
, dyn_size
, load_vaddr
- load_offset
);
296 else if (clazz
== ELFCLASS64
)
297 ret
= elf64_scan_dynamic(map
, dyn_offset
, dyn_size
, load_vaddr
- load_offset
);
301 munmap(map
, s
.st_size
);
307 void load_ldso_conf(const char *conf
)
309 FILE* fp
= fopen(conf
, "r");
313 DEBUG("failed to open %s\n", conf
);
320 if (!fgets(line
, 256, fp
))
327 if (line
[len
- 1] == '\n')
328 line
[len
- 1] = '\0';
329 if (!strncmp(line
, "include ", 8)) {
330 char *sep
= strstr(line
, " ");
338 if (glob(sep
, GLOB_NOESCAPE
| GLOB_MARK
, NULL
, &gl
)) {
339 ERROR("glob failed on %s\n", sep
);
342 for (i
= 0; i
< gl
.gl_pathc
; i
++)
343 load_ldso_conf(gl
.gl_pathv
[i
]);
350 alloc_library_path(line
);