libelf_phdr.c revision 4484
111250Sradhika.jagtap@ARM.com/*-
211250Sradhika.jagtap@ARM.com * Copyright (c) 2006 Joseph Koshy
311250Sradhika.jagtap@ARM.com * All rights reserved.
411250Sradhika.jagtap@ARM.com *
511250Sradhika.jagtap@ARM.com * Redistribution and use in source and binary forms, with or without
611250Sradhika.jagtap@ARM.com * modification, are permitted provided that the following conditions
711250Sradhika.jagtap@ARM.com * are met:
811250Sradhika.jagtap@ARM.com * 1. Redistributions of source code must retain the above copyright
911250Sradhika.jagtap@ARM.com *    notice, this list of conditions and the following disclaimer.
1011250Sradhika.jagtap@ARM.com * 2. Redistributions in binary form must reproduce the above copyright
1111250Sradhika.jagtap@ARM.com *    notice, this list of conditions and the following disclaimer in the
1211250Sradhika.jagtap@ARM.com *    documentation and/or other materials provided with the distribution.
1311250Sradhika.jagtap@ARM.com *
1411250Sradhika.jagtap@ARM.com * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
1511250Sradhika.jagtap@ARM.com * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
1611250Sradhika.jagtap@ARM.com * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
1711250Sradhika.jagtap@ARM.com * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
1811250Sradhika.jagtap@ARM.com * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
1911250Sradhika.jagtap@ARM.com * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
2011250Sradhika.jagtap@ARM.com * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
2111250Sradhika.jagtap@ARM.com * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
2211250Sradhika.jagtap@ARM.com * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
2311250Sradhika.jagtap@ARM.com * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
2411250Sradhika.jagtap@ARM.com * SUCH DAMAGE.
2511250Sradhika.jagtap@ARM.com *
2611250Sradhika.jagtap@ARM.com * $FreeBSD: src/lib/libelf/libelf_phdr.c,v 1.2 2006/12/25 02:22:22 jkoshy Exp $
2711250Sradhika.jagtap@ARM.com */
2811250Sradhika.jagtap@ARM.com
2911250Sradhika.jagtap@ARM.com#include <assert.h>
3011250Sradhika.jagtap@ARM.com#include <stdlib.h>
3111250Sradhika.jagtap@ARM.com
3211250Sradhika.jagtap@ARM.com#include "gelf.h"
3311250Sradhika.jagtap@ARM.com#include "libelf.h"
3411250Sradhika.jagtap@ARM.com#include "_libelf.h"
3511250Sradhika.jagtap@ARM.com
3611250Sradhika.jagtap@ARM.comvoid *
3711250Sradhika.jagtap@ARM.com_libelf_getphdr(Elf *e, int ec)
3811250Sradhika.jagtap@ARM.com{
3911250Sradhika.jagtap@ARM.com        size_t phnum, phentsize;
4011250Sradhika.jagtap@ARM.com        size_t fsz, msz;
4111250Sradhika.jagtap@ARM.com        uint64_t phoff;
4211250Sradhika.jagtap@ARM.com        Elf32_Ehdr *eh32;
4311250Sradhika.jagtap@ARM.com        Elf64_Ehdr *eh64;
4411250Sradhika.jagtap@ARM.com        void *ehdr, *phdr;
4511250Sradhika.jagtap@ARM.com        void (*xlator)(char *_d, char *_s, size_t _c, int _swap);
4611250Sradhika.jagtap@ARM.com
4711250Sradhika.jagtap@ARM.com        assert(ec == ELFCLASS32 || ec == ELFCLASS64);
4811250Sradhika.jagtap@ARM.com
4911250Sradhika.jagtap@ARM.com        if (e == NULL) {
5011250Sradhika.jagtap@ARM.com                LIBELF_SET_ERROR(ARGUMENT, 0);
5111250Sradhika.jagtap@ARM.com                return (NULL);
5211250Sradhika.jagtap@ARM.com        }
5311250Sradhika.jagtap@ARM.com
5411250Sradhika.jagtap@ARM.com        if ((phdr = (ec == ELFCLASS32 ?
5511250Sradhika.jagtap@ARM.com                 (void *) e->e_u.e_elf.e_phdr.e_phdr32 :
5611250Sradhika.jagtap@ARM.com                 (void *) e->e_u.e_elf.e_phdr.e_phdr64)) != NULL)
5711250Sradhika.jagtap@ARM.com                return (phdr);
5811250Sradhika.jagtap@ARM.com
5911250Sradhika.jagtap@ARM.com        /*
6011250Sradhika.jagtap@ARM.com         * Check the PHDR related fields in the EHDR for sanity.
6111250Sradhika.jagtap@ARM.com         */
6211250Sradhika.jagtap@ARM.com
6311250Sradhika.jagtap@ARM.com        if ((ehdr = _libelf_ehdr(e, ec, 0)) == NULL)
6411250Sradhika.jagtap@ARM.com                return (NULL);
6511250Sradhika.jagtap@ARM.com
6611250Sradhika.jagtap@ARM.com        phnum = e->e_u.e_elf.e_nphdr;
6711250Sradhika.jagtap@ARM.com
6811250Sradhika.jagtap@ARM.com        if (ec == ELFCLASS32) {
6911250Sradhika.jagtap@ARM.com                eh32      = (Elf32_Ehdr *) ehdr;
7011250Sradhika.jagtap@ARM.com                phentsize = eh32->e_phentsize;
7111250Sradhika.jagtap@ARM.com                phoff     = (uint64_t) eh32->e_phoff;
7211250Sradhika.jagtap@ARM.com        } else {
7311250Sradhika.jagtap@ARM.com                eh64      = (Elf64_Ehdr *) ehdr;
7411250Sradhika.jagtap@ARM.com                phentsize = eh64->e_phentsize;
7511250Sradhika.jagtap@ARM.com                phoff     = (uint64_t) eh64->e_phoff;
7611250Sradhika.jagtap@ARM.com        }
7711250Sradhika.jagtap@ARM.com
7811250Sradhika.jagtap@ARM.com        fsz = gelf_fsize(e, ELF_T_PHDR, phnum, e->e_version);
7911250Sradhika.jagtap@ARM.com
8011250Sradhika.jagtap@ARM.com        assert(fsz > 0);
8111250Sradhika.jagtap@ARM.com
8211250Sradhika.jagtap@ARM.com        if ((uint64_t) e->e_rawsize < (phoff + fsz)) {
8311250Sradhika.jagtap@ARM.com                LIBELF_SET_ERROR(HEADER, 0);
8411250Sradhika.jagtap@ARM.com                return (NULL);
8511250Sradhika.jagtap@ARM.com        }
8611250Sradhika.jagtap@ARM.com
8711250Sradhika.jagtap@ARM.com        msz = _libelf_msize(ELF_T_PHDR, ec, EV_CURRENT);
8811250Sradhika.jagtap@ARM.com
8911250Sradhika.jagtap@ARM.com        assert(msz > 0);
9011250Sradhika.jagtap@ARM.com
9111250Sradhika.jagtap@ARM.com        if ((phdr = calloc(phnum, msz)) == NULL) {
9211250Sradhika.jagtap@ARM.com                LIBELF_SET_ERROR(RESOURCE, 0);
9311250Sradhika.jagtap@ARM.com                return (NULL);
9411250Sradhika.jagtap@ARM.com        }
9511250Sradhika.jagtap@ARM.com
9611250Sradhika.jagtap@ARM.com        if (ec == ELFCLASS32)
9711250Sradhika.jagtap@ARM.com                e->e_u.e_elf.e_phdr.e_phdr32 = phdr;
9811250Sradhika.jagtap@ARM.com        else
9911250Sradhika.jagtap@ARM.com                e->e_u.e_elf.e_phdr.e_phdr64 = phdr;
10011250Sradhika.jagtap@ARM.com
10111250Sradhika.jagtap@ARM.com
10211250Sradhika.jagtap@ARM.com        xlator = _libelf_get_translator(ELF_T_PHDR, ELF_TOMEMORY, ec);
10311250Sradhika.jagtap@ARM.com        (*xlator)(phdr, e->e_rawfile + phoff, phnum,
10411250Sradhika.jagtap@ARM.com            e->e_byteorder != LIBELF_PRIVATE(byteorder));
10511250Sradhika.jagtap@ARM.com
10611250Sradhika.jagtap@ARM.com        return (phdr);
10711250Sradhika.jagtap@ARM.com}
10811250Sradhika.jagtap@ARM.com
10911250Sradhika.jagtap@ARM.comvoid *
11011250Sradhika.jagtap@ARM.com_libelf_newphdr(Elf *e, int ec, size_t count)
11111250Sradhika.jagtap@ARM.com{
11211250Sradhika.jagtap@ARM.com        void *ehdr, *newphdr, *oldphdr;
11311250Sradhika.jagtap@ARM.com        size_t msz;
11411250Sradhika.jagtap@ARM.com
11511250Sradhika.jagtap@ARM.com        if (e == NULL) {
11611250Sradhika.jagtap@ARM.com                LIBELF_SET_ERROR(ARGUMENT, 0);
11711250Sradhika.jagtap@ARM.com                return (NULL);
11811250Sradhika.jagtap@ARM.com        }
11911250Sradhika.jagtap@ARM.com
12011250Sradhika.jagtap@ARM.com        if ((ehdr = _libelf_ehdr(e, ec, 0)) == NULL) {
12111250Sradhika.jagtap@ARM.com                LIBELF_SET_ERROR(SEQUENCE, 0);
12211250Sradhika.jagtap@ARM.com                return (NULL);
12311250Sradhika.jagtap@ARM.com        }
12411250Sradhika.jagtap@ARM.com
12511250Sradhika.jagtap@ARM.com        assert(e->e_class == ec);
12611250Sradhika.jagtap@ARM.com        assert(ec == ELFCLASS32 || ec == ELFCLASS64);
12711250Sradhika.jagtap@ARM.com        assert(e->e_version == EV_CURRENT);
12811250Sradhika.jagtap@ARM.com
12911250Sradhika.jagtap@ARM.com        msz = _libelf_msize(ELF_T_PHDR, ec, e->e_version);
13011250Sradhika.jagtap@ARM.com
13111250Sradhika.jagtap@ARM.com        assert(msz > 0);
13211250Sradhika.jagtap@ARM.com
13311250Sradhika.jagtap@ARM.com        newphdr = NULL;
13411250Sradhika.jagtap@ARM.com        if (count > 0 && (newphdr = calloc(count, msz)) == NULL) {
13511250Sradhika.jagtap@ARM.com                LIBELF_SET_ERROR(RESOURCE, 0);
13611250Sradhika.jagtap@ARM.com                return (NULL);
13711250Sradhika.jagtap@ARM.com        }
13811250Sradhika.jagtap@ARM.com
13911250Sradhika.jagtap@ARM.com        if (ec == ELFCLASS32) {
14011250Sradhika.jagtap@ARM.com                if ((oldphdr = (void *) e->e_u.e_elf.e_phdr.e_phdr32) != NULL)
14111250Sradhika.jagtap@ARM.com                        free(oldphdr);
14211250Sradhika.jagtap@ARM.com                e->e_u.e_elf.e_phdr.e_phdr32 = (Elf32_Phdr *) newphdr;
14311250Sradhika.jagtap@ARM.com        } else {
14411250Sradhika.jagtap@ARM.com                if ((oldphdr = (void *) e->e_u.e_elf.e_phdr.e_phdr64) != NULL)
14511250Sradhika.jagtap@ARM.com                        free(oldphdr);
14611250Sradhika.jagtap@ARM.com                e->e_u.e_elf.e_phdr.e_phdr64 = (Elf64_Phdr *) newphdr;
14711250Sradhika.jagtap@ARM.com        }
14811250Sradhika.jagtap@ARM.com
14911250Sradhika.jagtap@ARM.com        e->e_u.e_elf.e_nphdr = count;
15011250Sradhika.jagtap@ARM.com
15111250Sradhika.jagtap@ARM.com        elf_flagphdr(e, ELF_C_SET, ELF_F_DIRTY);
15211250Sradhika.jagtap@ARM.com
15311250Sradhika.jagtap@ARM.com        return (newphdr);
15411250Sradhika.jagtap@ARM.com}
15511250Sradhika.jagtap@ARM.com