1 /* Test program for elf_update function.
2    Copyright (C) 2000, 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 
32 int
33 main (int argc, char *argv[] __attribute__ ((unused)))
34 {
35   const char *fname = "xxx_update2";
36   int fd;
37   Elf *elf;
38   Elf32_Ehdr *ehdr;
39   Elf32_Phdr *phdr;
40   int i;
41 
42   fd = open (fname, O_RDWR | O_CREAT | O_TRUNC, 0666);
43   if (fd == -1)
44     {
45       printf ("cannot open `%s': %s\n", fname, strerror (errno));
46       exit (1);
47     }
48 
49   elf_version (EV_CURRENT);
50 
51   elf = elf_begin (fd, ELF_C_WRITE, NULL);
52   if (elf == NULL)
53     {
54       printf ("cannot create ELF descriptor: %s\n", elf_errmsg (-1));
55       exit (1);
56     }
57 
58   /* Create an ELF header.  */
59   ehdr = elf32_newehdr (elf);
60   if (ehdr == NULL)
61     {
62       printf ("cannot create ELF header: %s\n", elf_errmsg (-1));
63       exit (1);
64     }
65 
66   /* Print the ELF header values.  */
67   if (argc > 1)
68     {
69       for (i = 0; i < EI_NIDENT; ++i)
70 	printf (" %02x", ehdr->e_ident[i]);
71       printf ("\
72 \ntype = %hu\nmachine = %hu\nversion = %u\nentry = %u\nphoff = %u\n"
73 	      "shoff = %u\nflags = %u\nehsize = %hu\nphentsize = %hu\n"
74 	      "phnum = %hu\nshentsize = %hu\nshnum = %hu\nshstrndx = %hu\n",
75 	      ehdr->e_type, ehdr->e_machine, ehdr->e_version, ehdr->e_entry,
76 	      ehdr->e_phoff, ehdr->e_shoff, ehdr->e_flags, ehdr->e_ehsize,
77 	      ehdr->e_phentsize, ehdr->e_phnum, ehdr->e_shentsize,
78 	      ehdr->e_shnum, ehdr->e_shstrndx);
79     }
80 
81   ehdr->e_ident[0] = 42;
82   ehdr->e_ident[4] = 1;
83   ehdr->e_ident[5] = 1;
84   ehdr->e_ident[6] = 2;
85   ehdr->e_type = ET_EXEC;
86   ehdr->e_version = 1;
87   ehdr->e_ehsize = 1;
88   elf_flagehdr (elf, ELF_C_SET, ELF_F_DIRTY);
89 
90   /* Create the program header.  */
91   phdr = elf32_newphdr (elf, 1);
92   if (phdr == NULL)
93     {
94       printf ("cannot create program header: %s\n", elf_errmsg (-1));
95       exit (1);
96     }
97 
98   phdr[0].p_type = PT_PHDR;
99   elf_flagphdr (elf, ELF_C_SET, ELF_F_DIRTY);
100 
101   /* Let the library compute the internal structure information.  */
102   if (elf_update (elf, ELF_C_NULL) < 0)
103     {
104       printf ("failure in elf_update(NULL): %s\n", elf_errmsg (-1));
105       exit (1);
106     }
107 
108   ehdr = elf32_getehdr (elf);
109 
110   phdr[0].p_offset = ehdr->e_phoff;
111   phdr[0].p_offset = ehdr->e_phoff;
112   phdr[0].p_vaddr = ehdr->e_phoff;
113   phdr[0].p_paddr = ehdr->e_phoff;
114   phdr[0].p_flags = PF_R | PF_X;
115   phdr[0].p_filesz = ehdr->e_phnum * elf32_fsize (ELF_T_PHDR, 1, EV_CURRENT);
116   phdr[0].p_memsz = ehdr->e_phnum * elf32_fsize (ELF_T_PHDR, 1, EV_CURRENT);
117   phdr[0].p_align = sizeof (Elf32_Word);
118 
119   /* Write out the file.  */
120   if (elf_update (elf, ELF_C_WRITE) < 0)
121     {
122       printf ("failure in elf_update(WRITE): %s\n", elf_errmsg (-1));
123       exit (1);
124     }
125 
126   /* Print the ELF header values.  */
127   if (argc > 1)
128     {
129       for (i = 0; i < EI_NIDENT; ++i)
130 	printf (" %02x", ehdr->e_ident[i]);
131       printf ("\
132 \ntype = %hu\nmachine = %hu\nversion = %u\nentry = %u\nphoff = %u\n"
133 	      "shoff = %u\nflags = %u\nehsize = %hu\nphentsize = %hu\n"
134 	      "phnum = %hu\nshentsize = %hu\nshnum = %hu\nshstrndx = %hu\n",
135 	      ehdr->e_type, ehdr->e_machine, ehdr->e_version, ehdr->e_entry,
136 	      ehdr->e_phoff, ehdr->e_shoff, ehdr->e_flags, ehdr->e_ehsize,
137 	      ehdr->e_phentsize, ehdr->e_phnum, ehdr->e_shentsize,
138 	      ehdr->e_shnum, ehdr->e_shstrndx);
139     }
140 
141   if (elf_end (elf) != 0)
142     {
143       printf ("failure in elf_end: %s\n", elf_errmsg (-1));
144       exit (1);
145     }
146 
147   unlink (fname);
148 
149   return 0;
150 }
151