1 /*- 2 * Copyright (c) 2003 Jake Burkholder. 3 * Copyright 1996-1998 John D. Polstra. 4 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org> 5 * Copyright (c) 1998 Peter Wemm <peter@freebsd.org> 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include <sys/types.h> 34 #include <machine/elf.h> 35 36 #include <stand.h> 37 38 #define FREEBSD_ELF 39 #include <sys/link_elf.h> 40 41 #include "bootstrap.h" 42 43 #define COPYOUT(s,d,l) archsw.arch_copyout((vm_offset_t)(s), d, l) 44 45 /* 46 * Apply a single intra-module relocation to the data. `relbase' is the 47 * target relocation base for the section (i.e. it corresponds to where 48 * r_offset == 0). `dataaddr' is the relocated address corresponding to 49 * the start of the data, and `len' is the number of bytes. 50 */ 51 int 52 __elfN(reloc)(struct elf_file *ef, symaddr_fn *symaddr, const void *reldata, 53 int reltype, Elf_Addr relbase, Elf_Addr dataaddr, void *data, size_t len) 54 { 55 #if (defined(__i386__) || defined(__amd64__)) && __ELF_WORD_SIZE == 64 56 Elf64_Addr *where, val; 57 Elf_Addr addend, addr; 58 Elf_Size rtype, symidx; 59 const Elf_Rel *rel; 60 const Elf_Rela *rela; 61 62 switch (reltype) { 63 case ELF_RELOC_REL: 64 rel = (const Elf_Rel *)reldata; 65 where = (Elf_Addr *)((char *)data + relbase + rel->r_offset - 66 dataaddr); 67 addend = 0; 68 rtype = ELF_R_TYPE(rel->r_info); 69 symidx = ELF_R_SYM(rel->r_info); 70 addend = 0; 71 break; 72 case ELF_RELOC_RELA: 73 rela = (const Elf_Rela *)reldata; 74 where = (Elf_Addr *)((char *)data + relbase + rela->r_offset - 75 dataaddr); 76 addend = rela->r_addend; 77 rtype = ELF_R_TYPE(rela->r_info); 78 symidx = ELF_R_SYM(rela->r_info); 79 break; 80 default: 81 return (EINVAL); 82 } 83 84 if ((char *)where < (char *)data || (char *)where >= (char *)data + len) 85 return (0); 86 87 if (reltype == ELF_RELOC_REL) 88 addend = *where; 89 90 /* XXX, definitions not available on i386. */ 91 #define R_X86_64_64 1 92 #define R_X86_64_RELATIVE 8 93 #define R_X86_64_IRELATIVE 37 94 95 switch (rtype) { 96 case R_X86_64_64: /* S + A */ 97 addr = symaddr(ef, symidx); 98 if (addr == 0) 99 return (ESRCH); 100 val = addr + addend; 101 *where = val; 102 break; 103 case R_X86_64_RELATIVE: 104 addr = (Elf_Addr)addend + relbase; 105 val = addr; 106 *where = val; 107 break; 108 case R_X86_64_IRELATIVE: 109 /* leave it to kernel */ 110 break; 111 default: 112 printf("\nunhandled relocation type %u\n", (u_int)rtype); 113 return (EFTYPE); 114 } 115 116 return (0); 117 #elif defined(__i386__) && __ELF_WORD_SIZE == 32 118 Elf_Addr addend, addr, *where, val; 119 Elf_Size rtype, symidx; 120 const Elf_Rel *rel; 121 const Elf_Rela *rela; 122 123 switch (reltype) { 124 case ELF_RELOC_REL: 125 rel = (const Elf_Rel *)reldata; 126 where = (Elf_Addr *)((char *)data + relbase + rel->r_offset - 127 dataaddr); 128 addend = 0; 129 rtype = ELF_R_TYPE(rel->r_info); 130 symidx = ELF_R_SYM(rel->r_info); 131 addend = 0; 132 break; 133 case ELF_RELOC_RELA: 134 rela = (const Elf_Rela *)reldata; 135 where = (Elf_Addr *)((char *)data + relbase + rela->r_offset - 136 dataaddr); 137 addend = rela->r_addend; 138 rtype = ELF_R_TYPE(rela->r_info); 139 symidx = ELF_R_SYM(rela->r_info); 140 break; 141 default: 142 return (EINVAL); 143 } 144 145 if ((char *)where < (char *)data || (char *)where >= (char *)data + len) 146 return (0); 147 148 if (reltype == ELF_RELOC_REL) 149 addend = *where; 150 151 /* XXX, definitions not available on amd64. */ 152 #define R_386_32 1 /* Add symbol value. */ 153 #define R_386_GLOB_DAT 6 /* Set GOT entry to data address. */ 154 #define R_386_RELATIVE 8 /* Add load address of shared object. */ 155 #define R_386_IRELATIVE 42 156 157 switch (rtype) { 158 case R_386_RELATIVE: 159 addr = addend + relbase; 160 *where = addr; 161 break; 162 case R_386_32: /* S + A */ 163 addr = symaddr(ef, symidx); 164 if (addr == 0) 165 return (ESRCH); 166 val = addr + addend; 167 *where = val; 168 break; 169 case R_386_IRELATIVE: 170 /* leave it to kernel */ 171 break; 172 default: 173 printf("\nunhandled relocation type %u\n", (u_int)rtype); 174 return (EFTYPE); 175 } 176 177 return (0); 178 #elif defined(__aarch64__) || defined(__arm__) || defined(__powerpc__) || \ 179 defined(__riscv) 180 Elf_Size w; 181 const Elf_Rela *rela; 182 183 switch (reltype) { 184 case ELF_RELOC_RELA: 185 rela = reldata; 186 if (relbase + rela->r_offset >= dataaddr && 187 relbase + rela->r_offset < dataaddr + len) { 188 switch (ELF_R_TYPE(rela->r_info)) { 189 #if defined(__aarch64__) 190 case R_AARCH64_RELATIVE: 191 #elif defined(__arm__) 192 case R_ARM_RELATIVE: 193 #elif defined(__powerpc__) 194 case R_PPC_RELATIVE: 195 #elif defined(__riscv) 196 case R_RISCV_RELATIVE: 197 #endif 198 w = relbase + rela->r_addend; 199 bcopy(&w, (u_char *)data + (relbase + 200 rela->r_offset - dataaddr), sizeof(w)); 201 break; 202 default: 203 printf("\nunhandled relocation type %u\n", 204 (u_int)ELF_R_TYPE(rela->r_info)); 205 return (EFTYPE); 206 } 207 } 208 break; 209 } 210 211 return (0); 212 #else 213 return (EOPNOTSUPP); 214 #endif 215 } 216