1 /*- 2 * Copyright 1996-1998 John D. Polstra. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 * 25 * $FreeBSD: src/sys/i386/i386/elf_machdep.c,v 1.8 1999/12/21 11:14:02 eivind Exp $ 26 */ 27 28 #include <sys/param.h> 29 #include <sys/kernel.h> 30 #include <sys/systm.h> 31 #include <sys/linker.h> 32 #include <sys/sysent.h> 33 #include <sys/imgact_elf.h> 34 #include <sys/syscall.h> 35 #include <sys/signalvar.h> 36 #include <sys/vnode.h> 37 #include <machine/elf.h> 38 #include <machine/md_var.h> 39 40 static struct sysentvec elf64_dragonfly_sysvec = { 41 .sv_size = SYS_MAXSYSCALL, 42 .sv_table = sysent, 43 .sv_sigsize = 0, 44 .sv_sigtbl = NULL, 45 .sv_errsize = 0, 46 .sv_errtbl = NULL, 47 .sv_transtrap = NULL, 48 .sv_fixup = __elfN(dragonfly_fixup), 49 .sv_sendsig = sendsig, 50 .sv_sigcode = sigcode, 51 .sv_szsigcode = &szsigcode, 52 .sv_name = "DragonFly ELF64", 53 .sv_coredump = __elfN(coredump), 54 .sv_imgact_try = NULL, 55 .sv_minsigstksz = MINSIGSTKSZ, 56 }; 57 58 static Elf64_Brandinfo dragonfly_brand_info = { 59 .brand = ELFOSABI_NONE, 60 .machine = EM_X86_64, 61 .compat_3_brand = "DragonFly", 62 .emul_path = NULL, 63 .interp_path = "/libexec/ld-elf.so.2", 64 .sysvec = &elf64_dragonfly_sysvec, 65 .interp_newpath = NULL, 66 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE, 67 .brand_note = &elf64_dragonfly_brandnote, 68 }; 69 70 SYSINIT(elf64, SI_SUB_EXEC, SI_ORDER_FIRST, 71 (sysinit_cfunc_t) elf64_insert_brand_entry, 72 &dragonfly_brand_info); 73 74 static Elf64_Brandinfo freebsd_brand_info = { 75 .brand = ELFOSABI_FREEBSD, 76 .machine = EM_X86_64, 77 .compat_3_brand = "FreeBSD", 78 .emul_path = NULL, 79 .interp_path = "/usr/libexec/ld-elf.so.1", 80 .sysvec = &elf64_dragonfly_sysvec, 81 .interp_newpath = NULL, 82 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE, 83 .brand_note = &elf64_freebsd_brandnote, 84 }; 85 86 SYSINIT(elf64_fbsd, SI_SUB_EXEC, SI_ORDER_ANY, 87 (sysinit_cfunc_t) elf64_insert_brand_entry, 88 &freebsd_brand_info); 89 90 /* Process one elf relocation with addend. */ 91 static int 92 elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data, 93 int type, int local, elf_lookup_fn lookup) 94 { 95 Elf64_Addr *where, val; 96 Elf32_Addr *where32, val32; 97 Elf_Addr addr; 98 Elf_Addr addend; 99 Elf_Size rtype, symidx; 100 const Elf_Rel *rel; 101 const Elf_Rela *rela; 102 103 switch (type) { 104 case ELF_RELOC_REL: 105 rel = (const Elf_Rel *)data; 106 where = (Elf_Addr *) (relocbase + rel->r_offset); 107 rtype = ELF_R_TYPE(rel->r_info); 108 symidx = ELF_R_SYM(rel->r_info); 109 /* Addend is 32 bit on 32 bit relocs */ 110 switch (rtype) { 111 case R_X86_64_PC32: 112 case R_X86_64_32: 113 case R_X86_64_32S: 114 addend = *(Elf32_Addr *)where; 115 break; 116 default: 117 addend = *where; 118 break; 119 } 120 break; 121 case ELF_RELOC_RELA: 122 rela = (const Elf_Rela *)data; 123 where = (Elf_Addr *) (relocbase + rela->r_offset); 124 addend = rela->r_addend; 125 rtype = ELF_R_TYPE(rela->r_info); 126 symidx = ELF_R_SYM(rela->r_info); 127 break; 128 default: 129 panic("unknown reloc type %d", type); 130 } 131 132 switch (rtype) { 133 134 case R_X86_64_NONE: /* none */ 135 break; 136 137 case R_X86_64_64: /* S + A */ 138 if (lookup(lf, symidx, 1, &addr)) 139 return -1; 140 val = addr + addend; 141 if (*where != val) 142 *where = val; 143 break; 144 145 case R_X86_64_PC32: /* S + A - P */ 146 if (lookup(lf, symidx, 1, &addr)) 147 return -1; 148 where32 = (Elf32_Addr *)where; 149 val32 = (Elf32_Addr)(addr + addend - (Elf_Addr)where); 150 if (*where32 != val32) 151 *where32 = val32; 152 break; 153 154 case R_X86_64_32: /* S + A zero extend */ 155 case R_X86_64_32S: /* S + A sign extend */ 156 if (lookup(lf, symidx, 1, &addr)) 157 return -1; 158 val32 = (Elf32_Addr)(addr + addend); 159 where32 = (Elf32_Addr *)where; 160 if (*where32 != val32) 161 *where32 = val32; 162 break; 163 164 case R_X86_64_COPY: /* none */ 165 /* 166 * There shouldn't be copy relocations in kernel 167 * objects. 168 */ 169 kprintf("kldload: unexpected R_COPY relocation\n"); 170 return -1; 171 break; 172 173 case R_X86_64_GLOB_DAT: /* S */ 174 case R_X86_64_JMP_SLOT: /* XXX need addend + offset */ 175 if (lookup(lf, symidx, 1, &addr)) 176 return -1; 177 if (*where != addr) 178 *where = addr; 179 break; 180 181 case R_X86_64_RELATIVE: /* B + A */ 182 addr = relocbase + addend; 183 val = addr; 184 if (*where != val) 185 *where = val; 186 break; 187 188 default: 189 kprintf("kldload: unexpected relocation type %ld\n", 190 rtype); 191 return -1; 192 } 193 return(0); 194 } 195 196 int 197 elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type, 198 elf_lookup_fn lookup) 199 { 200 201 return (elf_reloc_internal(lf, relocbase, data, type, 0, lookup)); 202 } 203 204 int 205 elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data, 206 int type, elf_lookup_fn lookup) 207 { 208 209 return (elf_reloc_internal(lf, relocbase, data, type, 1, lookup)); 210 } 211