1260684Skaiw/*- 2260684Skaiw * Copyright (c) 2006,2008 Joseph Koshy 3260684Skaiw * All rights reserved. 4260684Skaiw * 5260684Skaiw * Redistribution and use in source and binary forms, with or without 6260684Skaiw * modification, are permitted provided that the following conditions 7260684Skaiw * are met: 8260684Skaiw * 1. Redistributions of source code must retain the above copyright 9260684Skaiw * notice, this list of conditions and the following disclaimer. 10260684Skaiw * 2. Redistributions in binary form must reproduce the above copyright 11260684Skaiw * notice, this list of conditions and the following disclaimer in the 12260684Skaiw * documentation and/or other materials provided with the distribution. 13260684Skaiw * 14260684Skaiw * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15260684Skaiw * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16260684Skaiw * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17260684Skaiw * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18260684Skaiw * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19260684Skaiw * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20260684Skaiw * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21260684Skaiw * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22260684Skaiw * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23260684Skaiw * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24260684Skaiw * SUCH DAMAGE. 25260684Skaiw */ 26260684Skaiw 27260684Skaiw#include <ar.h> 28260684Skaiw#include <libelf.h> 29260684Skaiw 30260684Skaiw#include "_libelf.h" 31260684Skaiw 32367466SdimELFTC_VCSID("$Id: elf_rand.c 3716 2019-03-18 22:01:01Z jkoshy $"); 33260684Skaiw 34260684Skaiwoff_t 35260684Skaiwelf_rand(Elf *ar, off_t offset) 36260684Skaiw{ 37260684Skaiw struct ar_hdr *arh; 38367466Sdim off_t offset_of_member; 39260684Skaiw 40260684Skaiw if (ar == NULL || ar->e_kind != ELF_K_AR || 41260684Skaiw (offset & 1) || offset < SARMAG || 42367466Sdim offset >= ar->e_rawsize) { 43260684Skaiw LIBELF_SET_ERROR(ARGUMENT, 0); 44260684Skaiw return 0; 45260684Skaiw } 46260684Skaiw 47367466Sdim offset_of_member = offset + (off_t) sizeof(struct ar_hdr); 48367466Sdim 49367466Sdim if (offset_of_member <= 0 || /* Numeric overflow. */ 50367466Sdim offset_of_member >= ar->e_rawsize) { 51367466Sdim LIBELF_SET_ERROR(ARGUMENT, 0); 52367466Sdim return 0; 53367466Sdim } 54367466Sdim 55260684Skaiw arh = (struct ar_hdr *) (ar->e_rawfile + offset); 56260684Skaiw 57260684Skaiw /* a too simple sanity check */ 58260684Skaiw if (arh->ar_fmag[0] != '`' || arh->ar_fmag[1] != '\n') { 59260684Skaiw LIBELF_SET_ERROR(ARCHIVE, 0); 60260684Skaiw return 0; 61260684Skaiw } 62260684Skaiw 63260684Skaiw ar->e_u.e_ar.e_next = offset; 64260684Skaiw 65260684Skaiw return (offset); 66260684Skaiw} 67