1 /* Test program for elf_update function.
2 Copyright (C) 2000, 2001, 2002 Red Hat, Inc.
3 Written by Ulrich Drepper <drepper@redhat.com>, 2000.
4
5 This program is Open Source software; you can redistribute it and/or
6 modify it under the terms of the Open Software License version 1.0 as
7 published by the Open Source Initiative.
8
9 You should have received a copy of the Open Software License along
10 with this program; if not, you may obtain a copy of the Open Software
11 License version 1.0 from http://www.opensource.org/licenses/osl.php or
12 by writing the Open Source Initiative c/o Lawrence Rosen, Esq.,
13 3001 King Ranch Road, Ukiah, CA 95482. */
14
15 #ifdef HAVE_CONFIG_H
16 # include <config.h>
17 #endif
18
19 #include <errno.h>
20 #include <fcntl.h>
21 #include <libelf.h>
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include <string.h>
25 #include <unistd.h>
26
27 #include <libebl.h>
28
29
30 int
main(int argc,char * argv[])31 main (int argc, char *argv[])
32 {
33 const char fname[] = "xxx";
34 int fd;
35 Elf *elf;
36 Elf32_Ehdr *ehdr;
37 Elf32_Phdr *phdr;
38 Elf_Scn *scn;
39 Elf32_Shdr *shdr;
40 Elf_Data *data;
41 struct Ebl_Strtab *shst;
42 struct Ebl_Strent *firstse;
43 struct Ebl_Strent *secondse;
44 struct Ebl_Strent *thirdse;
45 struct Ebl_Strent *fourthse;
46 struct Ebl_Strent *shstrtabse;
47 int i;
48
49 fd = open (fname, O_RDWR | O_CREAT | O_TRUNC, 0666);
50 if (fd == -1)
51 {
52 printf ("cannot open `%s': %s\n", fname, strerror (errno));
53 exit (1);
54 }
55
56 elf_version (EV_CURRENT);
57
58 elf_fill (0x42);
59
60 elf = elf_begin (fd, ELF_C_WRITE, NULL);
61 if (elf == NULL)
62 {
63 printf ("cannot create ELF descriptor: %s\n", elf_errmsg (-1));
64 exit (1);
65 }
66
67 /* Create an ELF header. */
68 ehdr = elf32_newehdr (elf);
69 if (ehdr == NULL)
70 {
71 printf ("cannot create ELF header: %s\n", elf_errmsg (-1));
72 exit (1);
73 }
74
75 /* Print the ELF header values. */
76 if (argc > 1)
77 {
78 for (i = 0; i < EI_NIDENT; ++i)
79 printf (" %02x", ehdr->e_ident[i]);
80 printf ("\
81 \ntype = %hu\nmachine = %hu\nversion = %u\nentry = %u\nphoff = %u\n"
82 "shoff = %u\nflags = %u\nehsize = %hu\nphentsize = %hu\n"
83 "phnum = %hu\nshentsize = %hu\nshnum = %hu\nshstrndx = %hu\n",
84 ehdr->e_type, ehdr->e_machine, ehdr->e_version, ehdr->e_entry,
85 ehdr->e_phoff, ehdr->e_shoff, ehdr->e_flags, ehdr->e_ehsize,
86 ehdr->e_phentsize, ehdr->e_phnum, ehdr->e_shentsize,
87 ehdr->e_shnum, ehdr->e_shstrndx);
88 }
89
90 ehdr->e_ident[0] = 42;
91 ehdr->e_ident[4] = 1;
92 ehdr->e_ident[5] = 1;
93 ehdr->e_ident[6] = 2;
94 ehdr->e_type = ET_EXEC;
95 ehdr->e_version = 1;
96 ehdr->e_ehsize = 1;
97 elf_flagehdr (elf, ELF_C_SET, ELF_F_DIRTY);
98
99 /* Create the program header. */
100 phdr = elf32_newphdr (elf, 1);
101 if (phdr == NULL)
102 {
103 printf ("cannot create program header: %s\n", elf_errmsg (-1));
104 exit (1);
105 }
106
107 phdr[0].p_type = PT_PHDR;
108 elf_flagphdr (elf, ELF_C_SET, ELF_F_DIRTY);
109
110 shst = ebl_strtabinit (true);
111
112 scn = elf_newscn (elf);
113 if (scn == NULL)
114 {
115 printf ("cannot create first section: %s\n", elf_errmsg (-1));
116 exit (1);
117 }
118 shdr = elf32_getshdr (scn);
119 if (shdr == NULL)
120 {
121 printf ("cannot get header for first section: %s\n", elf_errmsg (-1));
122 exit (1);
123 }
124
125 firstse = ebl_strtabadd (shst, ".first", 0);
126
127 shdr->sh_type = SHT_PROGBITS;
128 shdr->sh_flags = SHF_ALLOC | SHF_EXECINSTR;
129 shdr->sh_addr = 0;
130 shdr->sh_link = 0;
131 shdr->sh_info = 0;
132 shdr->sh_entsize = 1;
133
134 data = elf_newdata (scn);
135 if (data == NULL)
136 {
137 printf ("cannot create data first section: %s\n", elf_errmsg (-1));
138 exit (1);
139 }
140
141 data->d_buf = "hello";
142 data->d_type = ELF_T_BYTE;
143 data->d_version = EV_CURRENT;
144 data->d_size = 5;
145 data->d_align = 16;
146
147
148 scn = elf_newscn (elf);
149 if (scn == NULL)
150 {
151 printf ("cannot create second section: %s\n", elf_errmsg (-1));
152 exit (1);
153 }
154 shdr = elf32_getshdr (scn);
155 if (shdr == NULL)
156 {
157 printf ("cannot get header for second section: %s\n", elf_errmsg (-1));
158 exit (1);
159 }
160
161 secondse = ebl_strtabadd (shst, ".second", 0);
162
163 shdr->sh_type = SHT_PROGBITS;
164 shdr->sh_flags = SHF_ALLOC | SHF_WRITE;
165 shdr->sh_addr = 0;
166 shdr->sh_link = 0;
167 shdr->sh_info = 0;
168 shdr->sh_entsize = 1;
169
170 data = elf_newdata (scn);
171 if (data == NULL)
172 {
173 printf ("cannot create data second section: %s\n", elf_errmsg (-1));
174 exit (1);
175 }
176
177 data->d_buf = "world";
178 data->d_type = ELF_T_BYTE;
179 data->d_version = EV_CURRENT;
180 data->d_size = 5;
181 data->d_align = 16;
182
183
184 scn = elf_newscn (elf);
185 if (scn == NULL)
186 {
187 printf ("cannot create third section: %s\n", elf_errmsg (-1));
188 exit (1);
189 }
190 shdr = elf32_getshdr (scn);
191 if (shdr == NULL)
192 {
193 printf ("cannot get header for third section: %s\n", elf_errmsg (-1));
194 exit (1);
195 }
196
197 thirdse = ebl_strtabadd (shst, ".third", 0);
198
199 shdr->sh_type = SHT_PROGBITS;
200 shdr->sh_flags = SHF_ALLOC | SHF_EXECINSTR;
201 shdr->sh_addr = 0;
202 shdr->sh_link = 0;
203 shdr->sh_info = 0;
204 shdr->sh_entsize = 1;
205
206 data = elf_newdata (scn);
207 if (data == NULL)
208 {
209 printf ("cannot create data third section: %s\n", elf_errmsg (-1));
210 exit (1);
211 }
212
213 data->d_buf = "!!!!!";
214 data->d_type = ELF_T_BYTE;
215 data->d_version = EV_CURRENT;
216 data->d_size = 5;
217 data->d_align = 16;
218
219
220 scn = elf_newscn (elf);
221 if (scn == NULL)
222 {
223 printf ("cannot create fourth section: %s\n", elf_errmsg (-1));
224 exit (1);
225 }
226 shdr = elf32_getshdr (scn);
227 if (shdr == NULL)
228 {
229 printf ("cannot get header for fourth section: %s\n", elf_errmsg (-1));
230 exit (1);
231 }
232
233 fourthse = ebl_strtabadd (shst, ".fourth", 0);
234
235 shdr->sh_type = SHT_NOBITS;
236 shdr->sh_flags = SHF_ALLOC | SHF_EXECINSTR;
237 shdr->sh_addr = 0;
238 shdr->sh_link = 0;
239 shdr->sh_info = 0;
240 shdr->sh_entsize = 1;
241 shdr->sh_size = 100;
242
243 data = elf_newdata (scn);
244 if (data == NULL)
245 {
246 printf ("cannot create data fourth section: %s\n", elf_errmsg (-1));
247 exit (1);
248 }
249
250 data->d_buf = NULL;
251 data->d_type = ELF_T_BYTE;
252 data->d_version = EV_CURRENT;
253 data->d_size = 100;
254 data->d_align = 16;
255
256
257 scn = elf_newscn (elf);
258 if (scn == NULL)
259 {
260 printf ("cannot create SHSTRTAB section: %s\n", elf_errmsg (-1));
261 exit (1);
262 }
263 shdr = elf32_getshdr (scn);
264 if (shdr == NULL)
265 {
266 printf ("cannot get header for SHSTRTAB section: %s\n", elf_errmsg (-1));
267 exit (1);
268 }
269
270 shstrtabse = ebl_strtabadd (shst, ".shstrtab", 0);
271
272 shdr->sh_type = SHT_STRTAB;
273 shdr->sh_flags = 0;
274 shdr->sh_addr = 0;
275 shdr->sh_link = SHN_UNDEF;
276 shdr->sh_info = SHN_UNDEF;
277 shdr->sh_entsize = 1;
278
279 /* We have to store the section index in the ELF header. */
280 ehdr->e_shstrndx = elf_ndxscn (scn);
281
282 data = elf_newdata (scn);
283 if (data == NULL)
284 {
285 printf ("cannot create data SHSTRTAB section: %s\n", elf_errmsg (-1));
286 exit (1);
287 }
288
289 /* No more sections, finalize the section header string table. */
290 ebl_strtabfinalize (shst, data);
291
292 elf32_getshdr (elf_getscn (elf, 1))->sh_name = ebl_strtaboffset (firstse);
293 elf32_getshdr (elf_getscn (elf, 2))->sh_name = ebl_strtaboffset (secondse);
294 elf32_getshdr (elf_getscn (elf, 3))->sh_name = ebl_strtaboffset (thirdse);
295 elf32_getshdr (elf_getscn (elf, 4))->sh_name = ebl_strtaboffset (fourthse);
296 shdr->sh_name = ebl_strtaboffset (shstrtabse);
297
298 /* Let the library compute the internal structure information. */
299 if (elf_update (elf, ELF_C_NULL) < 0)
300 {
301 printf ("failure in elf_update(NULL): %s\n", elf_errmsg (-1));
302 exit (1);
303 }
304
305 ehdr = elf32_getehdr (elf);
306
307 phdr[0].p_offset = ehdr->e_phoff;
308 phdr[0].p_offset = ehdr->e_phoff;
309 phdr[0].p_vaddr = ehdr->e_phoff;
310 phdr[0].p_paddr = ehdr->e_phoff;
311 phdr[0].p_flags = PF_R | PF_X;
312 phdr[0].p_filesz = ehdr->e_phnum * elf32_fsize (ELF_T_PHDR, 1, EV_CURRENT);
313 phdr[0].p_memsz = ehdr->e_phnum * elf32_fsize (ELF_T_PHDR, 1, EV_CURRENT);
314 phdr[0].p_align = sizeof (Elf32_Word);
315
316 /* Write out the file. */
317 if (elf_update (elf, ELF_C_WRITE) < 0)
318 {
319 printf ("failure in elf_update(WRITE): %s\n", elf_errmsg (-1));
320 exit (1);
321 }
322
323 /* We don't need the string table anymore. */
324 ebl_strtabfree (shst);
325
326 /* And the data allocated in the .shstrtab section. */
327 free (data->d_buf);
328
329 /* Print the ELF header values. */
330 if (argc > 1)
331 {
332 for (i = 0; i < EI_NIDENT; ++i)
333 printf (" %02x", ehdr->e_ident[i]);
334 printf ("\
335 \ntype = %hu\nmachine = %hu\nversion = %u\nentry = %u\nphoff = %u\n"
336 "shoff = %u\nflags = %u\nehsize = %hu\nphentsize = %hu\n"
337 "phnum = %hu\nshentsize = %hu\nshnum = %hu\nshstrndx = %hu\n",
338 ehdr->e_type, ehdr->e_machine, ehdr->e_version, ehdr->e_entry,
339 ehdr->e_phoff, ehdr->e_shoff, ehdr->e_flags, ehdr->e_ehsize,
340 ehdr->e_phentsize, ehdr->e_phnum, ehdr->e_shentsize,
341 ehdr->e_shnum, ehdr->e_shstrndx);
342 }
343
344 if (elf_end (elf) != 0)
345 {
346 printf ("failure in elf_end: %s\n", elf_errmsg (-1));
347 exit (1);
348 }
349
350 unlink (fname);
351
352 return 0;
353 }
354