1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 #include <string.h> 30 #include "machdep.h" 31 #include "reloc.h" 32 #include "_librtld.h" 33 #include "_elf.h" 34 35 /* 36 * Undo relocations that have been applied to a memory image. Basically this 37 * involves copying the original files relocation offset into the new image 38 * being created. 39 */ 40 /* ARGSUSED3 */ 41 void 42 undo_reloc(void *vrel, uchar_t *oaddr, uchar_t *iaddr, Reloc *reloc) 43 { 44 Rela *rel = vrel; 45 Xword rtype = ELF_R_TYPE(rel->r_info, M_MACH); 46 47 switch (rtype) { 48 case R_AMD64_NONE: 49 break; 50 case R_AMD64_COPY: 51 (void) memset((void *)oaddr, 0, (size_t)reloc->r_size); 52 break; 53 case R_AMD64_JUMP_SLOT: 54 { 55 /* LINTED */ 56 ulong_t *_oaddr = (ulong_t *)oaddr; 57 /* LINTED */ 58 ulong_t *_iaddr = (ulong_t *)iaddr; 59 60 if (_iaddr) 61 *_oaddr = *_iaddr + reloc->r_value; 62 else 63 *_oaddr = reloc->r_value; 64 } 65 break; 66 default: 67 { 68 size_t re_fsize = reloc_table[rtype].re_fsize; 69 70 if (iaddr) 71 (void) memcpy(oaddr, iaddr, re_fsize); 72 else 73 (void) memset(oaddr, 0, re_fsize); 74 } 75 } 76 } 77 78 /* 79 * Copy a relocation record and increment its value. The record must reflect 80 * the new address to which this image is fixed. Note that .got entries 81 * associated with .plt's must be fixed to the new base address. 82 */ 83 /* ARGSUSED3 */ 84 void 85 inc_reloc(void *vnrel, void *vorel, Reloc *reloc, uchar_t *oaddr, 86 uchar_t *iaddr) 87 { 88 Rela *nrel = vnrel; 89 Rela *orel = vorel; 90 91 if (ELF_R_TYPE(nrel->r_info, M_MACH) == R_AMD64_JUMP_SLOT) { 92 /* LINTED */ 93 ulong_t *_oaddr = (ulong_t *)oaddr; 94 /* LINTED */ 95 ulong_t *_iaddr = (ulong_t *)iaddr; 96 97 if (_iaddr) 98 *_oaddr = *_iaddr + reloc->r_value; 99 else 100 *_oaddr = reloc->r_value; 101 } 102 103 *nrel = *orel; 104 nrel->r_offset += reloc->r_value; 105 } 106 107 /* 108 * Clear a relocation record. The relocation has been applied to the image and 109 * thus the relocation must not occur again. 110 */ 111 void 112 clear_reloc(void *vrel) 113 { 114 Rela *rel = vrel; 115 116 rel->r_offset = 0; 117 rel->r_info = ELF_R_INFO(0, R_AMD64_NONE); 118 rel->r_addend = 0; 119 } 120 121 /* 122 * Apply a relocation to an image being built from an input file. Use the 123 * runtime linkers routines to do the necessary magic. 124 */ 125 void 126 apply_reloc(void *vrel, Reloc *reloc, const char *name, uchar_t *oaddr, 127 Rt_map *lmp) 128 { 129 Rela *rel = vrel; 130 Xword type = ELF_R_TYPE(rel->r_info, M_MACH); 131 Xword value = reloc->r_value + rel->r_addend; 132 133 if (type == R_AMD64_JUMP_SLOT) { 134 uintptr_t addr, vaddr; 135 136 if (FLAGS(lmp) & FLG_RT_FIXED) 137 vaddr = 0; 138 else 139 vaddr = ADDR(lmp); 140 141 addr = (uintptr_t)oaddr - rel->r_offset; 142 /* LINTED */ 143 elf_plt_write((uintptr_t)addr, vaddr, rel, 144 (uintptr_t)value, reloc->r_pltndx); 145 146 } else if (type == R_AMD64_COPY) { 147 (void) memcpy((void *)oaddr, (void *)value, 148 (size_t)reloc->r_size); 149 } else { 150 (void) do_reloc_rtld(type, oaddr, &value, reloc->r_name, name, 151 LIST(lmp)); 152 } 153 } 154