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 #pragma ident "%Z%%M% %I% %E% SMI" 27 28 #include <string.h> 29 #include "machdep.h" 30 #include "reloc.h" 31 #include "_librtld.h" 32 #include "_elf.h" 33 34 /* 35 * Undo relocations that have been applied to a memory image. Basically this 36 * involves copying the original files relocation offset into the new image 37 * being created. 38 */ 39 void 40 undo_reloc(void *vrel, uchar_t *oaddr, uchar_t *iaddr, Reloc *reloc) 41 { 42 Rel *rel = vrel; 43 /* LINTED */ 44 ulong_t *_oaddr = (ulong_t *)oaddr; 45 /* LINTED */ 46 ulong_t *_iaddr = (ulong_t *)iaddr; 47 48 switch (ELF_R_TYPE(rel->r_info, M_MACH)) { 49 case R_386_NONE: 50 break; 51 52 case R_386_COPY: 53 (void) memset((void *)oaddr, 0, (size_t)reloc->r_size); 54 break; 55 56 case R_386_JMP_SLOT: 57 if (_iaddr) 58 *_oaddr = *_iaddr + reloc->r_value; 59 else 60 *_oaddr = reloc->r_value; 61 break; 62 63 default: 64 if (_iaddr) 65 *_oaddr = *_iaddr; 66 else 67 *_oaddr = 0; 68 break; 69 } 70 } 71 72 /* 73 * Copy a relocation record and increment its value. The record must reflect 74 * the new address to which this image is fixed. Note that .got entries 75 * associated with .plt's must be fixed to the new base address. 76 */ 77 void 78 inc_reloc(void *vnrel, void *vorel, Reloc *reloc, uchar_t *oaddr, 79 uchar_t *iaddr) 80 { 81 Rel *nrel = vnrel; 82 Rel *orel = vorel; 83 /* LINTED */ 84 ulong_t *_oaddr = (ulong_t *)oaddr; 85 /* LINTED */ 86 ulong_t *_iaddr = (ulong_t *)iaddr; 87 88 if (ELF_R_TYPE(nrel->r_info, M_MACH) == R_386_JMP_SLOT) { 89 if (_iaddr) 90 *_oaddr = *_iaddr + reloc->r_value; 91 else 92 *_oaddr = reloc->r_value; 93 } 94 95 *nrel = *orel; 96 nrel->r_offset += reloc->r_value; 97 } 98 99 /* 100 * Clear a relocation record. The relocation has been applied to the image and 101 * thus the relocation must not occur again. 102 */ 103 void 104 clear_reloc(void *vrel) 105 { 106 Rel *rel = vrel; 107 108 rel->r_offset = 0; 109 rel->r_info = ELF_R_INFO(0, R_386_NONE); 110 } 111 112 /* 113 * Apply a relocation to an image being built from an input file. Use the 114 * runtime linkers routines to do the necessary magic. 115 */ 116 void 117 apply_reloc(void *vrel, Reloc *reloc, const char *name, uchar_t *oaddr, 118 Rt_map *lmp) 119 { 120 Rel *rel = vrel; 121 Xword type = ELF_R_TYPE(rel->r_info, M_MACH); 122 Word value = reloc->r_value; 123 124 if (type == R_386_JMP_SLOT) { 125 uintptr_t addr, vaddr; 126 127 if (FLAGS(lmp) & FLG_RT_FIXED) 128 vaddr = 0; 129 else 130 vaddr = ADDR(lmp); 131 addr = (uintptr_t)oaddr - rel->r_offset; 132 /* LINTED */ 133 elf_plt_write((uintptr_t)addr, vaddr, rel, 134 (uintptr_t)value, reloc->r_pltndx); 135 136 } else if (type == R_386_COPY) { 137 (void) memcpy((void *)oaddr, (void *)value, 138 (size_t)reloc->r_size); 139 } else { 140 (void) do_reloc_rtld(type, oaddr, &value, reloc->r_name, name, 141 LIST(lmp)); 142 } 143 } 144