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 #include "system.h"
31 
32 
33 int
main(int argc,char * argv[])34 main (int argc, char *argv[] __attribute__ ((unused)))
35 {
36   const char *fname = "xxx_update2";
37   int fd;
38   Elf *elf;
39   Elf32_Ehdr *ehdr;
40   Elf32_Phdr *phdr;
41   int i;
42 
43   fd = open (fname, O_RDWR | O_CREAT | O_TRUNC, DEFFILEMODE);
44   if (fd == -1)
45     {
46       printf ("cannot open `%s': %s\n", fname, strerror (errno));
47       exit (1);
48     }
49 
50   elf_version (EV_CURRENT);
51 
52   elf = elf_begin (fd, ELF_C_WRITE, NULL);
53   if (elf == NULL)
54     {
55       printf ("cannot create ELF descriptor: %s\n", elf_errmsg (-1));
56       exit (1);
57     }
58 
59   /* Create an ELF header.  */
60   ehdr = elf32_newehdr (elf);
61   if (ehdr == NULL)
62     {
63       printf ("cannot create ELF header: %s\n", elf_errmsg (-1));
64       exit (1);
65     }
66 
67   /* Print the ELF header values.  */
68   if (argc > 1)
69     {
70       for (i = 0; i < EI_NIDENT; ++i)
71 	printf (" %02x", ehdr->e_ident[i]);
72       printf ("\
73 \ntype = %hu\nmachine = %hu\nversion = %u\nentry = %u\nphoff = %u\n"
74 	      "shoff = %u\nflags = %u\nehsize = %hu\nphentsize = %hu\n"
75 	      "phnum = %hu\nshentsize = %hu\nshnum = %hu\nshstrndx = %hu\n",
76 	      ehdr->e_type, ehdr->e_machine, ehdr->e_version, ehdr->e_entry,
77 	      ehdr->e_phoff, ehdr->e_shoff, ehdr->e_flags, ehdr->e_ehsize,
78 	      ehdr->e_phentsize, ehdr->e_phnum, ehdr->e_shentsize,
79 	      ehdr->e_shnum, ehdr->e_shstrndx);
80     }
81 
82   ehdr->e_ident[0] = 42;
83   ehdr->e_ident[4] = 1;
84   ehdr->e_ident[5] = 1;
85   ehdr->e_ident[6] = 2;
86   ehdr->e_type = ET_EXEC;
87   ehdr->e_version = 1;
88   ehdr->e_ehsize = 1;
89   elf_flagehdr (elf, ELF_C_SET, ELF_F_DIRTY);
90 
91   /* Create the program header.  */
92   phdr = elf32_newphdr (elf, 1);
93   if (phdr == NULL)
94     {
95       printf ("cannot create program header: %s\n", elf_errmsg (-1));
96       exit (1);
97     }
98 
99   phdr[0].p_type = PT_PHDR;
100   elf_flagphdr (elf, ELF_C_SET, ELF_F_DIRTY);
101 
102   /* Let the library compute the internal structure information.  */
103   if (elf_update (elf, ELF_C_NULL) < 0)
104     {
105       printf ("failure in elf_update(NULL): %s\n", elf_errmsg (-1));
106       exit (1);
107     }
108 
109   ehdr = elf32_getehdr (elf);
110 
111   phdr[0].p_offset = ehdr->e_phoff;
112   phdr[0].p_offset = ehdr->e_phoff;
113   phdr[0].p_vaddr = ehdr->e_phoff;
114   phdr[0].p_paddr = ehdr->e_phoff;
115   phdr[0].p_flags = PF_R | PF_X;
116   phdr[0].p_filesz = ehdr->e_phnum * elf32_fsize (ELF_T_PHDR, 1, EV_CURRENT);
117   phdr[0].p_memsz = ehdr->e_phnum * elf32_fsize (ELF_T_PHDR, 1, EV_CURRENT);
118   phdr[0].p_align = sizeof (Elf32_Word);
119 
120   /* Write out the file.  */
121   if (elf_update (elf, ELF_C_WRITE) < 0)
122     {
123       printf ("failure in elf_update(WRITE): %s\n", elf_errmsg (-1));
124       exit (1);
125     }
126 
127   /* Print the ELF header values.  */
128   if (argc > 1)
129     {
130       for (i = 0; i < EI_NIDENT; ++i)
131 	printf (" %02x", ehdr->e_ident[i]);
132       printf ("\
133 \ntype = %hu\nmachine = %hu\nversion = %u\nentry = %u\nphoff = %u\n"
134 	      "shoff = %u\nflags = %u\nehsize = %hu\nphentsize = %hu\n"
135 	      "phnum = %hu\nshentsize = %hu\nshnum = %hu\nshstrndx = %hu\n",
136 	      ehdr->e_type, ehdr->e_machine, ehdr->e_version, ehdr->e_entry,
137 	      ehdr->e_phoff, ehdr->e_shoff, ehdr->e_flags, ehdr->e_ehsize,
138 	      ehdr->e_phentsize, ehdr->e_phnum, ehdr->e_shentsize,
139 	      ehdr->e_shnum, ehdr->e_shstrndx);
140     }
141 
142   if (elf_end (elf) != 0)
143     {
144       printf ("failure in elf_end: %s\n", elf_errmsg (-1));
145       exit (1);
146     }
147 
148   unlink (fname);
149 
150   return 0;
151 }
152