1 /* Test program for elf_update function.
2 Copyright (C) 2000, 2001, 2002, 2005 Red Hat, Inc.
3 This file is part of elfutils.
4 Written by Ulrich Drepper <drepper@redhat.com>, 2000.
5
6 This file is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
10
11 elfutils is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
18
19 #ifdef HAVE_CONFIG_H
20 # include <config.h>
21 #endif
22
23 #include <errno.h>
24 #include <fcntl.h>
25 #include <libelf.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <unistd.h>
30
31 #include ELFUTILS_HEADER(ebl)
32
33
34 int
main(int argc,char * argv[])35 main (int argc, char *argv[] __attribute__ ((unused)))
36 {
37 const char fname[] = "xxx_update4";
38 int fd;
39 Elf *elf;
40 Elf32_Ehdr *ehdr;
41 Elf32_Phdr *phdr;
42 Elf_Scn *scn;
43 Elf32_Shdr *shdr;
44 Elf_Data *data;
45 struct Ebl_Strtab *shst;
46 struct Ebl_Strent *firstse;
47 struct Ebl_Strent *secondse;
48 struct Ebl_Strent *thirdse;
49 struct Ebl_Strent *fourthse;
50 struct Ebl_Strent *shstrtabse;
51 int i;
52
53 fd = open (fname, O_RDWR | O_CREAT | O_TRUNC, 0666);
54 if (fd == -1)
55 {
56 printf ("cannot open `%s': %s\n", fname, strerror (errno));
57 exit (1);
58 }
59
60 elf_version (EV_CURRENT);
61
62 elf_fill (0x42);
63
64 elf = elf_begin (fd, ELF_C_WRITE, NULL);
65 if (elf == NULL)
66 {
67 printf ("cannot create ELF descriptor: %s\n", elf_errmsg (-1));
68 exit (1);
69 }
70
71 /* Create an ELF header. */
72 ehdr = elf32_newehdr (elf);
73 if (ehdr == NULL)
74 {
75 printf ("cannot create ELF header: %s\n", elf_errmsg (-1));
76 exit (1);
77 }
78
79 /* Print the ELF header values. */
80 if (argc > 1)
81 {
82 for (i = 0; i < EI_NIDENT; ++i)
83 printf (" %02x", ehdr->e_ident[i]);
84 printf ("\
85 \ntype = %hu\nmachine = %hu\nversion = %u\nentry = %u\nphoff = %u\n"
86 "shoff = %u\nflags = %u\nehsize = %hu\nphentsize = %hu\n"
87 "phnum = %hu\nshentsize = %hu\nshnum = %hu\nshstrndx = %hu\n",
88 ehdr->e_type, ehdr->e_machine, ehdr->e_version, ehdr->e_entry,
89 ehdr->e_phoff, ehdr->e_shoff, ehdr->e_flags, ehdr->e_ehsize,
90 ehdr->e_phentsize, ehdr->e_phnum, ehdr->e_shentsize,
91 ehdr->e_shnum, ehdr->e_shstrndx);
92 }
93
94 ehdr->e_ident[0] = 42;
95 ehdr->e_ident[4] = 1;
96 ehdr->e_ident[5] = 1;
97 ehdr->e_ident[6] = 2;
98 ehdr->e_type = ET_EXEC;
99 ehdr->e_version = 1;
100 ehdr->e_ehsize = 1;
101 elf_flagehdr (elf, ELF_C_SET, ELF_F_DIRTY);
102
103 /* Create the program header. */
104 phdr = elf32_newphdr (elf, 1);
105 if (phdr == NULL)
106 {
107 printf ("cannot create program header: %s\n", elf_errmsg (-1));
108 exit (1);
109 }
110
111 phdr[0].p_type = PT_PHDR;
112 elf_flagphdr (elf, ELF_C_SET, ELF_F_DIRTY);
113
114 shst = ebl_strtabinit (true);
115
116 scn = elf_newscn (elf);
117 if (scn == NULL)
118 {
119 printf ("cannot create first section: %s\n", elf_errmsg (-1));
120 exit (1);
121 }
122 shdr = elf32_getshdr (scn);
123 if (shdr == NULL)
124 {
125 printf ("cannot get header for first section: %s\n", elf_errmsg (-1));
126 exit (1);
127 }
128
129 firstse = ebl_strtabadd (shst, ".first", 0);
130
131 shdr->sh_type = SHT_PROGBITS;
132 shdr->sh_flags = SHF_ALLOC | SHF_EXECINSTR;
133 shdr->sh_addr = 0;
134 shdr->sh_link = 0;
135 shdr->sh_info = 0;
136 shdr->sh_entsize = 1;
137
138 data = elf_newdata (scn);
139 if (data == NULL)
140 {
141 printf ("cannot create data first section: %s\n", elf_errmsg (-1));
142 exit (1);
143 }
144
145 data->d_buf = "hello";
146 data->d_type = ELF_T_BYTE;
147 data->d_version = EV_CURRENT;
148 data->d_size = 5;
149 data->d_align = 16;
150
151
152 scn = elf_newscn (elf);
153 if (scn == NULL)
154 {
155 printf ("cannot create second section: %s\n", elf_errmsg (-1));
156 exit (1);
157 }
158 shdr = elf32_getshdr (scn);
159 if (shdr == NULL)
160 {
161 printf ("cannot get header for second section: %s\n", elf_errmsg (-1));
162 exit (1);
163 }
164
165 secondse = ebl_strtabadd (shst, ".second", 0);
166
167 shdr->sh_type = SHT_PROGBITS;
168 shdr->sh_flags = SHF_ALLOC | SHF_WRITE;
169 shdr->sh_addr = 0;
170 shdr->sh_link = 0;
171 shdr->sh_info = 0;
172 shdr->sh_entsize = 1;
173
174 data = elf_newdata (scn);
175 if (data == NULL)
176 {
177 printf ("cannot create data second section: %s\n", elf_errmsg (-1));
178 exit (1);
179 }
180
181 data->d_buf = "world";
182 data->d_type = ELF_T_BYTE;
183 data->d_version = EV_CURRENT;
184 data->d_size = 5;
185 data->d_align = 16;
186
187
188 scn = elf_newscn (elf);
189 if (scn == NULL)
190 {
191 printf ("cannot create third section: %s\n", elf_errmsg (-1));
192 exit (1);
193 }
194 shdr = elf32_getshdr (scn);
195 if (shdr == NULL)
196 {
197 printf ("cannot get header for third section: %s\n", elf_errmsg (-1));
198 exit (1);
199 }
200
201 thirdse = ebl_strtabadd (shst, ".third", 0);
202
203 shdr->sh_type = SHT_PROGBITS;
204 shdr->sh_flags = SHF_ALLOC | SHF_EXECINSTR;
205 shdr->sh_addr = 0;
206 shdr->sh_link = 0;
207 shdr->sh_info = 0;
208 shdr->sh_entsize = 1;
209
210 data = elf_newdata (scn);
211 if (data == NULL)
212 {
213 printf ("cannot create data third section: %s\n", elf_errmsg (-1));
214 exit (1);
215 }
216
217 data->d_buf = "!!!!!";
218 data->d_type = ELF_T_BYTE;
219 data->d_version = EV_CURRENT;
220 data->d_size = 5;
221 data->d_align = 16;
222
223
224 scn = elf_newscn (elf);
225 if (scn == NULL)
226 {
227 printf ("cannot create fourth section: %s\n", elf_errmsg (-1));
228 exit (1);
229 }
230 shdr = elf32_getshdr (scn);
231 if (shdr == NULL)
232 {
233 printf ("cannot get header for fourth section: %s\n", elf_errmsg (-1));
234 exit (1);
235 }
236
237 fourthse = ebl_strtabadd (shst, ".fourth", 0);
238
239 shdr->sh_type = SHT_NOBITS;
240 shdr->sh_flags = SHF_ALLOC | SHF_EXECINSTR;
241 shdr->sh_addr = 0;
242 shdr->sh_link = 0;
243 shdr->sh_info = 0;
244 shdr->sh_entsize = 1;
245 shdr->sh_size = 100;
246
247 data = elf_newdata (scn);
248 if (data == NULL)
249 {
250 printf ("cannot create data fourth section: %s\n", elf_errmsg (-1));
251 exit (1);
252 }
253
254 data->d_buf = NULL;
255 data->d_type = ELF_T_BYTE;
256 data->d_version = EV_CURRENT;
257 data->d_size = 100;
258 data->d_align = 16;
259
260
261 scn = elf_newscn (elf);
262 if (scn == NULL)
263 {
264 printf ("cannot create SHSTRTAB section: %s\n", elf_errmsg (-1));
265 exit (1);
266 }
267 shdr = elf32_getshdr (scn);
268 if (shdr == NULL)
269 {
270 printf ("cannot get header for SHSTRTAB section: %s\n", elf_errmsg (-1));
271 exit (1);
272 }
273
274 shstrtabse = ebl_strtabadd (shst, ".shstrtab", 0);
275
276 shdr->sh_type = SHT_STRTAB;
277 shdr->sh_flags = 0;
278 shdr->sh_addr = 0;
279 shdr->sh_link = SHN_UNDEF;
280 shdr->sh_info = SHN_UNDEF;
281 shdr->sh_entsize = 1;
282
283 /* We have to store the section index in the ELF header. */
284 ehdr->e_shstrndx = elf_ndxscn (scn);
285
286 data = elf_newdata (scn);
287 if (data == NULL)
288 {
289 printf ("cannot create data SHSTRTAB section: %s\n", elf_errmsg (-1));
290 exit (1);
291 }
292
293 /* No more sections, finalize the section header string table. */
294 ebl_strtabfinalize (shst, data);
295
296 elf32_getshdr (elf_getscn (elf, 1))->sh_name = ebl_strtaboffset (firstse);
297 elf32_getshdr (elf_getscn (elf, 2))->sh_name = ebl_strtaboffset (secondse);
298 elf32_getshdr (elf_getscn (elf, 3))->sh_name = ebl_strtaboffset (thirdse);
299 elf32_getshdr (elf_getscn (elf, 4))->sh_name = ebl_strtaboffset (fourthse);
300 shdr->sh_name = ebl_strtaboffset (shstrtabse);
301
302 /* Let the library compute the internal structure information. */
303 if (elf_update (elf, ELF_C_NULL) < 0)
304 {
305 printf ("failure in elf_update(NULL): %s\n", elf_errmsg (-1));
306 exit (1);
307 }
308
309 ehdr = elf32_getehdr (elf);
310
311 phdr[0].p_offset = ehdr->e_phoff;
312 phdr[0].p_offset = ehdr->e_phoff;
313 phdr[0].p_vaddr = ehdr->e_phoff;
314 phdr[0].p_paddr = ehdr->e_phoff;
315 phdr[0].p_flags = PF_R | PF_X;
316 phdr[0].p_filesz = ehdr->e_phnum * elf32_fsize (ELF_T_PHDR, 1, EV_CURRENT);
317 phdr[0].p_memsz = ehdr->e_phnum * elf32_fsize (ELF_T_PHDR, 1, EV_CURRENT);
318 phdr[0].p_align = sizeof (Elf32_Word);
319
320 /* Write out the file. */
321 if (elf_update (elf, ELF_C_WRITE) < 0)
322 {
323 printf ("failure in elf_update(WRITE): %s\n", elf_errmsg (-1));
324 exit (1);
325 }
326
327 /* We don't need the string table anymore. */
328 ebl_strtabfree (shst);
329
330 /* And the data allocated in the .shstrtab section. */
331 free (data->d_buf);
332
333 /* Print the ELF header values. */
334 if (argc > 1)
335 {
336 for (i = 0; i < EI_NIDENT; ++i)
337 printf (" %02x", ehdr->e_ident[i]);
338 printf ("\
339 \ntype = %hu\nmachine = %hu\nversion = %u\nentry = %u\nphoff = %u\n"
340 "shoff = %u\nflags = %u\nehsize = %hu\nphentsize = %hu\n"
341 "phnum = %hu\nshentsize = %hu\nshnum = %hu\nshstrndx = %hu\n",
342 ehdr->e_type, ehdr->e_machine, ehdr->e_version, ehdr->e_entry,
343 ehdr->e_phoff, ehdr->e_shoff, ehdr->e_flags, ehdr->e_ehsize,
344 ehdr->e_phentsize, ehdr->e_phnum, ehdr->e_shentsize,
345 ehdr->e_shnum, ehdr->e_shstrndx);
346 }
347
348 if (elf_end (elf) != 0)
349 {
350 printf ("failure in elf_end: %s\n", elf_errmsg (-1));
351 exit (1);
352 }
353
354 unlink (fname);
355
356 return 0;
357 }
358