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_mask = -1, 44 .sv_sigsize = 0, 45 .sv_sigtbl = NULL, 46 .sv_errsize = 0, 47 .sv_errtbl = NULL, 48 .sv_transtrap = NULL, 49 .sv_fixup = __elfN(dragonfly_fixup), 50 .sv_sendsig = sendsig, 51 .sv_sigcode = sigcode, 52 .sv_szsigcode = &szsigcode, 53 .sv_prepsyscall = NULL, 54 .sv_name = "DragonFly ELF64", 55 .sv_coredump = __elfN(coredump), 56 .sv_imgact_try = NULL, 57 .sv_minsigstksz = MINSIGSTKSZ, 58 }; 59 60 static Elf64_Brandinfo dragonfly_brand_info = { 61 .brand = ELFOSABI_NONE, 62 .machine = EM_X86_64, 63 .compat_3_brand = "DragonFly", 64 .emul_path = NULL, 65 .interp_path = "/libexec/ld-elf.so.2", 66 .sysvec = &elf64_dragonfly_sysvec, 67 .interp_newpath = NULL, 68 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE, 69 .brand_note = &elf64_dragonfly_brandnote, 70 }; 71 72 SYSINIT(elf64, SI_SUB_EXEC, SI_ORDER_FIRST, 73 (sysinit_cfunc_t) elf64_insert_brand_entry, 74 &dragonfly_brand_info); 75 76 static Elf64_Brandinfo freebsd_brand_info = { 77 .brand = ELFOSABI_FREEBSD, 78 .machine = EM_X86_64, 79 .compat_3_brand = "FreeBSD", 80 .emul_path = NULL, 81 .interp_path = "/usr/libexec/ld-elf.so.1", 82 .sysvec = &elf64_dragonfly_sysvec, 83 .interp_newpath = NULL, 84 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE, 85 .brand_note = &elf64_freebsd_brandnote, 86 }; 87 88 SYSINIT(elf64_fbsd, SI_SUB_EXEC, SI_ORDER_ANY, 89 (sysinit_cfunc_t) elf64_insert_brand_entry, 90 &freebsd_brand_info); 91 92 /* Process one elf relocation with addend. */ 93 static int 94 elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data, 95 int type, int local, elf_lookup_fn lookup) 96 { 97 Elf64_Addr *where, val; 98 Elf32_Addr *where32, val32; 99 Elf_Addr addr; 100 Elf_Addr addend; 101 Elf_Size rtype, symidx; 102 const Elf_Rel *rel; 103 const Elf_Rela *rela; 104 105 switch (type) { 106 case ELF_RELOC_REL: 107 rel = (const Elf_Rel *)data; 108 where = (Elf_Addr *) (relocbase + rel->r_offset); 109 rtype = ELF_R_TYPE(rel->r_info); 110 symidx = ELF_R_SYM(rel->r_info); 111 /* Addend is 32 bit on 32 bit relocs */ 112 switch (rtype) { 113 case R_X86_64_PC32: 114 case R_X86_64_32: 115 case R_X86_64_32S: 116 addend = *(Elf32_Addr *)where; 117 break; 118 default: 119 addend = *where; 120 break; 121 } 122 break; 123 case ELF_RELOC_RELA: 124 rela = (const Elf_Rela *)data; 125 where = (Elf_Addr *) (relocbase + rela->r_offset); 126 addend = rela->r_addend; 127 rtype = ELF_R_TYPE(rela->r_info); 128 symidx = ELF_R_SYM(rela->r_info); 129 break; 130 default: 131 panic("unknown reloc type %d", type); 132 } 133 134 switch (rtype) { 135 136 case R_X86_64_NONE: /* none */ 137 break; 138 139 case R_X86_64_64: /* S + A */ 140 if (lookup(lf, symidx, 1, &addr)) 141 return -1; 142 val = addr + addend; 143 if (*where != val) 144 *where = val; 145 break; 146 147 case R_X86_64_PC32: /* S + A - P */ 148 if (lookup(lf, symidx, 1, &addr)) 149 return -1; 150 where32 = (Elf32_Addr *)where; 151 val32 = (Elf32_Addr)(addr + addend - (Elf_Addr)where); 152 if (*where32 != val32) 153 *where32 = val32; 154 break; 155 156 case R_X86_64_32: /* S + A zero extend */ 157 case R_X86_64_32S: /* S + A sign extend */ 158 if (lookup(lf, symidx, 1, &addr)) 159 return -1; 160 val32 = (Elf32_Addr)(addr + addend); 161 where32 = (Elf32_Addr *)where; 162 if (*where32 != val32) 163 *where32 = val32; 164 break; 165 166 case R_X86_64_COPY: /* none */ 167 /* 168 * There shouldn't be copy relocations in kernel 169 * objects. 170 */ 171 kprintf("kldload: unexpected R_COPY relocation\n"); 172 return -1; 173 break; 174 175 case R_X86_64_GLOB_DAT: /* S */ 176 case R_X86_64_JMP_SLOT: /* XXX need addend + offset */ 177 if (lookup(lf, symidx, 1, &addr)) 178 return -1; 179 if (*where != addr) 180 *where = addr; 181 break; 182 183 case R_X86_64_RELATIVE: /* B + A */ 184 addr = relocbase + addend; 185 val = addr; 186 if (*where != val) 187 *where = val; 188 break; 189 190 default: 191 kprintf("kldload: unexpected relocation type %ld\n", 192 rtype); 193 return -1; 194 } 195 return(0); 196 } 197 198 int 199 elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type, 200 elf_lookup_fn lookup) 201 { 202 203 return (elf_reloc_internal(lf, relocbase, data, type, 0, lookup)); 204 } 205 206 int 207 elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data, 208 int type, elf_lookup_fn lookup) 209 { 210 211 return (elf_reloc_internal(lf, relocbase, data, type, 1, lookup)); 212 } 213