1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2003 Jake Burkholder. 5 * Copyright 1996-1998 John D. Polstra. 6 * All rights reserved. 7 * Copyright (c) 2023 Jessica Clarke <jrtc27@FreeBSD.org> 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31 #include <sys/endian.h> 32 33 #include <err.h> 34 #include <errno.h> 35 #include <gelf.h> 36 37 #include "kldelf.h" 38 39 /* 40 * Apply relocations to the values obtained from the file. `relbase' is the 41 * target relocation address of the section, and `dataoff/len' is the region 42 * that is to be relocated, and has been copied to *dest 43 */ 44 static int 45 ef_arm_reloc(struct elf_file *ef, const void *reldata, Elf_Type reltype, 46 GElf_Addr relbase, GElf_Addr dataoff, size_t len, void *dest) 47 { 48 char *where; 49 GElf_Addr addr, addend; 50 GElf_Size rtype, symidx; 51 const GElf_Rel *rel; 52 const GElf_Rela *rela; 53 54 switch (reltype) { 55 case ELF_T_REL: 56 rel = (const GElf_Rel *)reldata; 57 where = (char *)dest + (relbase + rel->r_offset - dataoff); 58 addend = 0; 59 rtype = GELF_R_TYPE(rel->r_info); 60 symidx = GELF_R_SYM(rel->r_info); 61 break; 62 case ELF_T_RELA: 63 rela = (const GElf_Rela *)reldata; 64 where = (char *)dest + (relbase + rela->r_offset - dataoff); 65 addend = rela->r_addend; 66 rtype = GELF_R_TYPE(rela->r_info); 67 symidx = GELF_R_SYM(rela->r_info); 68 break; 69 default: 70 return (EINVAL); 71 } 72 73 if (where < (char *)dest || where >= (char *)dest + len) 74 return (0); 75 76 if (reltype == ELF_T_REL) 77 addend = le32dec(where); 78 79 switch (rtype) { 80 case R_ARM_ABS32: /* S + A */ 81 addr = EF_SYMADDR(ef, symidx) + addend; 82 le32enc(where, addr); 83 break; 84 case R_ARM_RELATIVE: /* B + A */ 85 addr = relbase + addend; 86 le32enc(where, addr); 87 break; 88 default: 89 warnx("unhandled relocation type %d", (int)rtype); 90 } 91 return (0); 92 } 93 94 ELF_RELOC(ELFCLASS32, ELFDATA2LSB, EM_ARM, ef_arm_reloc); 95