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 2009 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #include <string.h> 28 #include "machdep.h" 29 #include "reloc.h" 30 #include "_librtld.h" 31 #include "_elf.h" 32 33 /* 34 * Undo relocations that have been applied to a memory image. Basically this 35 * involves copying the original files relocation offset into the new image 36 * being created. 37 */ 38 /* ARGSUSED3 */ 39 void 40 undo_reloc(void *vrel, uchar_t *oaddr, uchar_t *iaddr, Reloc *reloc) 41 { 42 Rela *rel = vrel; 43 Xword rtype = ELF_R_TYPE(rel->r_info, M_MACH); 44 45 switch (rtype) { 46 case R_AMD64_NONE: 47 break; 48 case R_AMD64_COPY: 49 (void) memset((void *)oaddr, 0, (size_t)reloc->r_size); 50 break; 51 case R_AMD64_JUMP_SLOT: 52 { 53 /* LINTED */ 54 ulong_t *_oaddr = (ulong_t *)oaddr; 55 /* LINTED */ 56 ulong_t *_iaddr = (ulong_t *)iaddr; 57 58 if (_iaddr) 59 *_oaddr = *_iaddr + reloc->r_value; 60 else 61 *_oaddr = reloc->r_value; 62 } 63 break; 64 default: 65 { 66 size_t re_fsize = reloc_table[rtype].re_fsize; 67 68 if (iaddr) 69 (void) memcpy(oaddr, iaddr, re_fsize); 70 else 71 (void) memset(oaddr, 0, re_fsize); 72 } 73 } 74 } 75 76 /* 77 * Copy a relocation record and increment its value. The record must reflect 78 * the new address to which this image is fixed. Note that .got entries 79 * associated with .plt's must be fixed to the new base address. 80 */ 81 /* ARGSUSED3 */ 82 void 83 inc_reloc(void *vnrel, void *vorel, Reloc *reloc, uchar_t *oaddr, 84 uchar_t *iaddr) 85 { 86 Rela *nrel = vnrel; 87 Rela *orel = vorel; 88 89 if (ELF_R_TYPE(nrel->r_info, M_MACH) == R_AMD64_JUMP_SLOT) { 90 /* LINTED */ 91 ulong_t *_oaddr = (ulong_t *)oaddr; 92 /* LINTED */ 93 ulong_t *_iaddr = (ulong_t *)iaddr; 94 95 if (_iaddr) 96 *_oaddr = *_iaddr + reloc->r_value; 97 else 98 *_oaddr = reloc->r_value; 99 } 100 101 *nrel = *orel; 102 nrel->r_offset += reloc->r_value; 103 } 104 105 /* 106 * Clear a relocation record. The relocation has been applied to the image and 107 * thus the relocation must not occur again. 108 */ 109 void 110 clear_reloc(void *vrel) 111 { 112 Rela *rel = vrel; 113 114 rel->r_offset = 0; 115 rel->r_info = ELF_R_INFO(0, R_AMD64_NONE); 116 rel->r_addend = 0; 117 } 118 119 /* 120 * Apply a relocation to an image being built from an input file. Use the 121 * runtime linkers routines to do the necessary magic. 122 */ 123 void 124 apply_reloc(void *vrel, Reloc *reloc, const char *name, uchar_t *oaddr, 125 Rt_map *lmp) 126 { 127 Rela *rel = vrel; 128 Xword type = ELF_R_TYPE(rel->r_info, M_MACH); 129 Xword value = reloc->r_value + rel->r_addend; 130 131 if (type == R_AMD64_JUMP_SLOT) { 132 uintptr_t addr, vaddr; 133 134 if (FLAGS(lmp) & FLG_RT_FIXED) 135 vaddr = 0; 136 else 137 vaddr = ADDR(lmp); 138 139 addr = (uintptr_t)oaddr - rel->r_offset; 140 /* LINTED */ 141 (void) elf_plt_write((uintptr_t)addr, vaddr, rel, 142 (uintptr_t)value, reloc->r_pltndx); 143 144 } else if (type == R_AMD64_COPY) { 145 (void) memcpy((void *)oaddr, (void *)value, 146 (size_t)reloc->r_size); 147 } else { 148 (void) do_reloc_rtld(type, oaddr, &value, reloc->r_name, name, 149 LIST(lmp)); 150 } 151 } 152