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 #include ELFUTILS_HEADER(ebl) 32 33 34 int 35 main (int argc, char *argv[] __attribute__ ((unused))) 36 { 37 const char *fname = "xxx_update3"; 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 *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 SHSTRTAB 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 SHSTRTAB section: %s\n", elf_errmsg (-1)); 122 exit (1); 123 } 124 125 shstrtabse = ebl_strtabadd (shst, ".shstrtab", 0); 126 127 shdr->sh_type = SHT_STRTAB; 128 shdr->sh_flags = 0; 129 shdr->sh_addr = 0; 130 shdr->sh_link = SHN_UNDEF; 131 shdr->sh_info = SHN_UNDEF; 132 shdr->sh_addralign = 1; 133 shdr->sh_entsize = 0; 134 135 /* We have to store the section index in the ELF header. */ 136 ehdr->e_shstrndx = elf_ndxscn (scn); 137 138 data = elf_newdata (scn); 139 if (data == NULL) 140 { 141 printf ("cannot create data SHSTRTAB section: %s\n", elf_errmsg (-1)); 142 exit (1); 143 } 144 145 /* No more sections, finalize the section header string table. */ 146 ebl_strtabfinalize (shst, data); 147 148 shdr->sh_name = ebl_strtaboffset (shstrtabse); 149 150 /* Let the library compute the internal structure information. */ 151 if (elf_update (elf, ELF_C_NULL) < 0) 152 { 153 printf ("failure in elf_update(NULL): %s\n", elf_errmsg (-1)); 154 exit (1); 155 } 156 157 ehdr = elf32_getehdr (elf); 158 159 phdr[0].p_offset = ehdr->e_phoff; 160 phdr[0].p_offset = ehdr->e_phoff; 161 phdr[0].p_vaddr = ehdr->e_phoff; 162 phdr[0].p_paddr = ehdr->e_phoff; 163 phdr[0].p_flags = PF_R | PF_X; 164 phdr[0].p_filesz = ehdr->e_phnum * elf32_fsize (ELF_T_PHDR, 1, EV_CURRENT); 165 phdr[0].p_memsz = ehdr->e_phnum * elf32_fsize (ELF_T_PHDR, 1, EV_CURRENT); 166 phdr[0].p_align = sizeof (Elf32_Word); 167 168 /* Write out the file. */ 169 if (elf_update (elf, ELF_C_WRITE) < 0) 170 { 171 printf ("failure in elf_update(WRITE): %s\n", elf_errmsg (-1)); 172 exit (1); 173 } 174 175 /* We don't need the string table anymore. */ 176 ebl_strtabfree (shst); 177 178 /* And the data allocated in the .shstrtab section. */ 179 free (data->d_buf); 180 181 /* Print the ELF header values. */ 182 if (argc > 1) 183 { 184 for (i = 0; i < EI_NIDENT; ++i) 185 printf (" %02x", ehdr->e_ident[i]); 186 printf ("\ 187 \ntype = %hu\nmachine = %hu\nversion = %u\nentry = %u\nphoff = %u\n" 188 "shoff = %u\nflags = %u\nehsize = %hu\nphentsize = %hu\n" 189 "phnum = %hu\nshentsize = %hu\nshnum = %hu\nshstrndx = %hu\n", 190 ehdr->e_type, ehdr->e_machine, ehdr->e_version, ehdr->e_entry, 191 ehdr->e_phoff, ehdr->e_shoff, ehdr->e_flags, ehdr->e_ehsize, 192 ehdr->e_phentsize, ehdr->e_phnum, ehdr->e_shentsize, 193 ehdr->e_shnum, ehdr->e_shstrndx); 194 } 195 196 if (elf_end (elf) != 0) 197 { 198 printf ("failure in elf_end: %s\n", elf_errmsg (-1)); 199 exit (1); 200 } 201 202 unlink (fname); 203 204 return 0; 205 } 206