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