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 * $FreeBSD$ 27 */ 28 29#include <sys/cdefs.h> 30__FBSDID("$FreeBSD$"); 31 32#include <assert.h> 33#include <gelf.h> 34#include <libelf.h> 35#include <stdlib.h> 36 37#include "_libelf.h" 38 39void * 40_libelf_getphdr(Elf *e, int ec) 41{ 42 size_t phnum, phentsize; 43 size_t fsz, msz; 44 uint64_t phoff; 45 Elf32_Ehdr *eh32; 46 Elf64_Ehdr *eh64; 47 void *ehdr, *phdr; 48 int (*xlator)(char *_d, size_t _dsz, char *_s, size_t _c, int _swap); 49 50 assert(ec == ELFCLASS32 || ec == ELFCLASS64); 51 52 if (e == NULL) { 53 LIBELF_SET_ERROR(ARGUMENT, 0); 54 return (NULL); 55 } 56 57 if ((phdr = (ec == ELFCLASS32 ? 58 (void *) e->e_u.e_elf.e_phdr.e_phdr32 : 59 (void *) e->e_u.e_elf.e_phdr.e_phdr64)) != NULL) 60 return (phdr); 61 62 /* 63 * Check the PHDR related fields in the EHDR for sanity. 64 */ 65 66 if ((ehdr = _libelf_ehdr(e, ec, 0)) == NULL) 67 return (NULL); 68 69 phnum = e->e_u.e_elf.e_nphdr; 70 71 if (ec == ELFCLASS32) { 72 eh32 = (Elf32_Ehdr *) ehdr; 73 phentsize = eh32->e_phentsize; 74 phoff = (uint64_t) eh32->e_phoff; 75 } else { 76 eh64 = (Elf64_Ehdr *) ehdr; 77 phentsize = eh64->e_phentsize; 78 phoff = (uint64_t) eh64->e_phoff; 79 } 80 81 fsz = gelf_fsize(e, ELF_T_PHDR, phnum, e->e_version); 82 83 assert(fsz > 0); 84 85 if ((uint64_t) e->e_rawsize < (phoff + fsz)) { 86 LIBELF_SET_ERROR(HEADER, 0); 87 return (NULL); 88 } 89 90 msz = _libelf_msize(ELF_T_PHDR, ec, EV_CURRENT); 91 92 assert(msz > 0); 93 94 if ((phdr = calloc(phnum, msz)) == NULL) { 95 LIBELF_SET_ERROR(RESOURCE, 0); 96 return (NULL); 97 } 98 99 if (ec == ELFCLASS32) 100 e->e_u.e_elf.e_phdr.e_phdr32 = phdr; 101 else 102 e->e_u.e_elf.e_phdr.e_phdr64 = phdr; 103 104 105 xlator = _libelf_get_translator(ELF_T_PHDR, ELF_TOMEMORY, ec); 106 (*xlator)(phdr, phnum * msz, e->e_rawfile + phoff, phnum, 107 e->e_byteorder != LIBELF_PRIVATE(byteorder)); 108 109 return (phdr); 110} 111 112void * 113_libelf_newphdr(Elf *e, int ec, size_t count) 114{ 115 void *ehdr, *newphdr, *oldphdr; 116 size_t msz; 117 118 if (e == NULL) { 119 LIBELF_SET_ERROR(ARGUMENT, 0); 120 return (NULL); 121 } 122 123 if ((ehdr = _libelf_ehdr(e, ec, 0)) == NULL) { 124 LIBELF_SET_ERROR(SEQUENCE, 0); 125 return (NULL); 126 } 127 128 assert(e->e_class == ec); 129 assert(ec == ELFCLASS32 || ec == ELFCLASS64); 130 assert(e->e_version == EV_CURRENT); 131 132 msz = _libelf_msize(ELF_T_PHDR, ec, e->e_version); 133 134 assert(msz > 0); 135 136 newphdr = NULL; 137 if (count > 0 && (newphdr = calloc(count, msz)) == NULL) { 138 LIBELF_SET_ERROR(RESOURCE, 0); 139 return (NULL); 140 } 141 142 if (ec == ELFCLASS32) { 143 if ((oldphdr = (void *) e->e_u.e_elf.e_phdr.e_phdr32) != NULL) 144 free(oldphdr); 145 e->e_u.e_elf.e_phdr.e_phdr32 = (Elf32_Phdr *) newphdr; 146 } else { 147 if ((oldphdr = (void *) e->e_u.e_elf.e_phdr.e_phdr64) != NULL) 148 free(oldphdr); 149 e->e_u.e_elf.e_phdr.e_phdr64 = (Elf64_Phdr *) newphdr; 150 } 151 152 e->e_u.e_elf.e_nphdr = count; 153 154 elf_flagphdr(e, ELF_C_SET, ELF_F_DIRTY); 155 156 return (newphdr); 157} 158