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(__aarch64__) || defined(__amd64__) || defined(__i386__)) && \ 56 __ELF_WORD_SIZE == 64 57 Elf64_Addr *where, val; 58 Elf_Addr addend, addr; 59 Elf_Size rtype, symidx; 60 const Elf_Rel *rel; 61 const Elf_Rela *rela; 62 63 switch (reltype) { 64 case ELF_RELOC_REL: 65 rel = (const Elf_Rel *)reldata; 66 where = (Elf_Addr *)((char *)data + relbase + rel->r_offset - 67 dataaddr); 68 addend = 0; 69 rtype = ELF_R_TYPE(rel->r_info); 70 symidx = ELF_R_SYM(rel->r_info); 71 addend = 0; 72 break; 73 case ELF_RELOC_RELA: 74 rela = (const Elf_Rela *)reldata; 75 where = (Elf_Addr *)((char *)data + relbase + rela->r_offset - 76 dataaddr); 77 addend = rela->r_addend; 78 rtype = ELF_R_TYPE(rela->r_info); 79 symidx = ELF_R_SYM(rela->r_info); 80 break; 81 default: 82 return (EINVAL); 83 } 84 85 if ((char *)where < (char *)data || (char *)where >= (char *)data + len) 86 return (0); 87 88 if (reltype == ELF_RELOC_REL) 89 addend = *where; 90 91 #if defined(__aarch64__) 92 #define RELOC_RELATIVE R_AARCH64_RELATIVE 93 #define RELOC_IRELATIVE R_AARCH64_IRELATIVE 94 #elif defined(__amd64__) || defined(__i386__) 95 /* XXX, definitions not available on i386. */ 96 #define R_X86_64_64 1 97 #define R_X86_64_RELATIVE 8 98 #define R_X86_64_IRELATIVE 37 99 100 #define RELOC_RELATIVE R_X86_64_RELATIVE 101 #define RELOC_IRELATIVE R_X86_64_IRELATIVE 102 #endif 103 104 switch (rtype) { 105 case RELOC_RELATIVE: 106 addr = (Elf_Addr)addend + relbase; 107 val = addr; 108 memcpy(where, &val, sizeof(val)); 109 break; 110 case RELOC_IRELATIVE: 111 /* leave it to kernel */ 112 break; 113 #if defined(__amd64__) || defined(__i386__) 114 case R_X86_64_64: /* S + A */ 115 addr = symaddr(ef, symidx); 116 if (addr == 0) 117 return (ESRCH); 118 val = addr + addend; 119 *where = val; 120 break; 121 #endif 122 default: 123 printf("\nunhandled relocation type %u\n", (u_int)rtype); 124 return (EFTYPE); 125 } 126 127 return (0); 128 #elif defined(__i386__) && __ELF_WORD_SIZE == 32 129 Elf_Addr addend, addr, *where, val; 130 Elf_Size rtype, symidx; 131 const Elf_Rel *rel; 132 const Elf_Rela *rela; 133 134 switch (reltype) { 135 case ELF_RELOC_REL: 136 rel = (const Elf_Rel *)reldata; 137 where = (Elf_Addr *)((char *)data + relbase + rel->r_offset - 138 dataaddr); 139 addend = 0; 140 rtype = ELF_R_TYPE(rel->r_info); 141 symidx = ELF_R_SYM(rel->r_info); 142 addend = 0; 143 break; 144 case ELF_RELOC_RELA: 145 rela = (const Elf_Rela *)reldata; 146 where = (Elf_Addr *)((char *)data + relbase + rela->r_offset - 147 dataaddr); 148 addend = rela->r_addend; 149 rtype = ELF_R_TYPE(rela->r_info); 150 symidx = ELF_R_SYM(rela->r_info); 151 break; 152 default: 153 return (EINVAL); 154 } 155 156 if ((char *)where < (char *)data || (char *)where >= (char *)data + len) 157 return (0); 158 159 if (reltype == ELF_RELOC_REL) 160 addend = *where; 161 162 /* XXX, definitions not available on amd64. */ 163 #define R_386_32 1 /* Add symbol value. */ 164 #define R_386_GLOB_DAT 6 /* Set GOT entry to data address. */ 165 #define R_386_RELATIVE 8 /* Add load address of shared object. */ 166 #define R_386_IRELATIVE 42 167 168 switch (rtype) { 169 case R_386_RELATIVE: 170 addr = addend + relbase; 171 *where = addr; 172 break; 173 case R_386_32: /* S + A */ 174 addr = symaddr(ef, symidx); 175 if (addr == 0) 176 return (ESRCH); 177 val = addr + addend; 178 *where = val; 179 break; 180 case R_386_IRELATIVE: 181 /* leave it to kernel */ 182 break; 183 default: 184 printf("\nunhandled relocation type %u\n", (u_int)rtype); 185 return (EFTYPE); 186 } 187 188 return (0); 189 #elif defined(__powerpc__) || defined(__riscv) 190 Elf_Size w; 191 const Elf_Rela *rela; 192 193 switch (reltype) { 194 case ELF_RELOC_RELA: 195 rela = reldata; 196 if (relbase + rela->r_offset >= dataaddr && 197 relbase + rela->r_offset < dataaddr + len) { 198 switch (ELF_R_TYPE(rela->r_info)) { 199 #if defined(__powerpc__) 200 case R_PPC_RELATIVE: 201 #elif defined(__riscv) 202 case R_RISCV_RELATIVE: 203 #endif 204 w = relbase + rela->r_addend; 205 bcopy(&w, (u_char *)data + (relbase + 206 rela->r_offset - dataaddr), sizeof(w)); 207 break; 208 default: 209 printf("\nunhandled relocation type %u\n", 210 (u_int)ELF_R_TYPE(rela->r_info)); 211 return (EFTYPE); 212 } 213 } 214 break; 215 } 216 217 return (0); 218 #else 219 return (EOPNOTSUPP); 220 #endif 221 } 222