ext/libelf/gelf_phdr.c

   1 /*-
   2  * Copyright (c) 2006 Joseph Koshy
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  */
  26
  27 #include <limits.h>
  28
  29 #include "gelf.h"
  30 #include "libelf.h"
  31
  32 #include "_libelf.h"
  33
  34 Elf32_Phdr *
  35 elf32_getphdr(Elf *e)
  36 {
  37         return (_libelf_getphdr(e, ELFCLASS32));
  38 }
  39
  40 Elf64_Phdr *
  41 elf64_getphdr(Elf *e)
  42 {
  43         return (_libelf_getphdr(e, ELFCLASS64));
  44 }
  45
  46 GElf_Phdr *
  47 gelf_getphdr(Elf *e, int index, GElf_Phdr *d)
  48 {
  49         int ec;
  50         Elf32_Ehdr *eh32;
  51         Elf64_Ehdr *eh64;
  52         Elf32_Phdr *ep32;
  53         Elf64_Phdr *ep64;
  54
  55         if (d == NULL || e == NULL ||
  56             ((ec = e->e_class) != ELFCLASS32 && ec != ELFCLASS64) ||
  57             (e->e_kind != ELF_K_ELF) || index < 0) {
  58                 LIBELF_SET_ERROR(ARGUMENT, 0);
  59                 return (NULL);
  60         }
  61
  62         if (ec == ELFCLASS32) {
  63                 if ((eh32 = _libelf_ehdr(e, ELFCLASS32, 0)) == NULL ||
  64                     ((ep32 = _libelf_getphdr(e, ELFCLASS32)) == NULL))
  65                         return (NULL);
  66
  67                 if (index >= eh32->e_phnum) {
  68                         LIBELF_SET_ERROR(ARGUMENT, 0);
  69                         return (NULL);
  70                 }
  71
  72                 ep32 += index;
  73
  74                 d->p_type   = ep32->p_type;
  75                 d->p_offset = ep32->p_offset;
  76                 d->p_vaddr  = (Elf64_Addr) ep32->p_vaddr;
  77                 d->p_paddr  = (Elf64_Addr) ep32->p_paddr;
  78                 d->p_filesz = (Elf64_Xword) ep32->p_filesz;
  79                 d->p_memsz  = (Elf64_Xword) ep32->p_memsz;
  80                 d->p_flags  = ep32->p_flags;
  81                 d->p_align  = (Elf64_Xword) ep32->p_align;
  82
  83         } else {
  84                 if ((eh64 = _libelf_ehdr(e, ELFCLASS64, 0)) == NULL ||
  85                     (ep64 = _libelf_getphdr(e, ELFCLASS64)) == NULL)
  86                         return (NULL);
  87
  88                 if (index >= eh64->e_phnum) {
  89                         LIBELF_SET_ERROR(ARGUMENT, 0);
  90                         return (NULL);
  91                 }
  92
  93                 ep64 += index;
  94
  95                 *d = *ep64;
  96         }
  97
  98         return (d);
  99 }
 100
 101 Elf32_Phdr *
 102 elf32_newphdr(Elf *e, size_t count)
 103 {
 104         return (_libelf_newphdr(e, ELFCLASS32, count));
 105 }
 106
 107 Elf64_Phdr *
 108 elf64_newphdr(Elf *e, size_t count)
 109 {
 110         return (_libelf_newphdr(e, ELFCLASS64, count));
 111 }
 112
 113 void *
 114 gelf_newphdr(Elf *e, size_t count)
 115 {
 116         if (e == NULL) {
 117                 LIBELF_SET_ERROR(ARGUMENT, 0);
 118                 return (NULL);
 119         }
 120         return (_libelf_newphdr(e, e->e_class, count));
 121 }
 122
 123 int
 124 gelf_update_phdr(Elf *e, int ndx, GElf_Phdr *s)
 125 {
 126         int ec, phnum;
 127         void *ehdr;
 128         Elf32_Phdr *ph32;
 129         Elf64_Phdr *ph64;
 130
 131         if (s == NULL || e == NULL || e->e_kind != ELF_K_ELF ||
 132             ((ec = e->e_class) != ELFCLASS32 && ec != ELFCLASS64)) {
 133                 LIBELF_SET_ERROR(ARGUMENT, 0);
 134                 return (0);
 135         }
 136
 137         if (e->e_cmd == ELF_C_READ) {
 138                 LIBELF_SET_ERROR(MODE, 0);
 139                 return (0);
 140         }
 141
 142         if ((ehdr = _libelf_ehdr(e, ec, 0)) == NULL)
 143                 return (0);
 144
 145         if (ec == ELFCLASS32)
 146                 phnum = ((Elf32_Ehdr *) ehdr)->e_phnum;
 147         else
 148                 phnum = ((Elf64_Ehdr *) ehdr)->e_phnum;
 149
 150         if (ndx < 0 || ndx > phnum) {
 151                 LIBELF_SET_ERROR(ARGUMENT, 0);
 152                 return (0);
 153         }
 154
 155         if (ec == ELFCLASS64) {
 156                 ph64 = e->e_u.e_elf.e_phdr.e_phdr64 + ndx;
 157                 *ph64 = *s;
 158                 return (1);
 159         }
 160
 161         ph32 = e->e_u.e_elf.e_phdr.e_phdr32 + ndx;
 162
 163         ph32->p_type     =  s->p_type;
 164         ph32->p_flags    =  s->p_flags;
 165         LIBELF_COPY_U32(ph32, s, p_offset);
 166         LIBELF_COPY_U32(ph32, s, p_vaddr);
 167         LIBELF_COPY_U32(ph32, s, p_paddr);
 168         LIBELF_COPY_U32(ph32, s, p_filesz);
 169         LIBELF_COPY_U32(ph32, s, p_memsz);
 170         LIBELF_COPY_U32(ph32, s, p_align);
 171
 172         (void) elf_flagphdr(e, ELF_C_SET, ELF_F_DIRTY);
 173
 174         return (1);
 175 }