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 (c) 1995, 2010, Oracle and/or its affiliates. All rights reserved. 24 */ 25 26 /* 27 * Copyright 2019 Joyent, Inc. 28 */ 29 30 /* 31 * While this is no longer relevant to the kernel, we keep it in its 32 * traditional location to match the other variants, used from the ld 33 * code. 34 */ 35 36 #define ELF_TARGET_386 37 #if defined(DO_RELOC_LIBLD) 38 #undef DO_RELOC_LIBLD 39 #define DO_RELOC_LIBLD_X86 40 #endif 41 #include <stdio.h> 42 #include "sgs.h" 43 #include "machdep.h" 44 #include "libld.h" 45 #include "reloc.h" 46 #include "conv.h" 47 #include "msg.h" 48 49 /* 50 * We need to build this code differently when it is used for 51 * cross linking: 52 * - Data alignment requirements can differ from those 53 * of the running system, so we can't access data 54 * in units larger than a byte 55 * - We have to include code to do byte swapping when the 56 * target and linker host use different byte ordering, 57 * but such code is a waste when running natively. 58 */ 59 #if !defined(DO_RELOC_LIBLD) || defined(__x86) 60 #define DORELOC_NATIVE 61 #endif 62 63 /* 64 * This table represents the current relocations that do_reloc() is able to 65 * process. The relocations below that are marked SPECIAL are relocations that 66 * take special processing and shouldn't actually ever be passed to do_reloc(). 67 */ 68 const Rel_entry reloc_table[R_386_NUM] = { 69 [R_386_NONE] = {0, FLG_RE_NOTREL, 0, 0, 0}, 70 [R_386_32] = {0, FLG_RE_NOTREL, 4, 0, 0}, 71 [R_386_PC32] = {0, FLG_RE_PCREL, 4, 0, 0}, 72 [R_386_GOT32] = {0, FLG_RE_GOTADD, 4, 0, 0}, 73 [R_386_PLT32] = {0, FLG_RE_PLTREL | FLG_RE_PCREL, 4, 0, 0}, 74 [R_386_COPY] = {0, FLG_RE_NOTREL, 0, 0, 0}, /* SPECIAL */ 75 [R_386_GLOB_DAT] = {0, FLG_RE_NOTREL, 4, 0, 0}, 76 [R_386_JMP_SLOT] = {0, FLG_RE_NOTREL, 4, 0, 0}, /* SPECIAL */ 77 [R_386_RELATIVE] = {0, FLG_RE_NOTREL, 4, 0, 0}, 78 [R_386_GOTOFF] = {0, FLG_RE_GOTREL, 4, 0, 0}, 79 [R_386_GOTPC] = {0, FLG_RE_PCREL | FLG_RE_GOTPC | 80 FLG_RE_LOCLBND, 4, 0, 0}, 81 [R_386_32PLT] = {0, FLG_RE_PLTREL, 4, 0, 0}, 82 [R_386_TLS_GD_PLT] = {0, FLG_RE_PLTREL | FLG_RE_PCREL | 83 FLG_RE_TLSGD, 4, 0, 0}, 84 [R_386_TLS_LDM_PLT] = {0, FLG_RE_PLTREL | FLG_RE_PCREL | 85 FLG_RE_TLSLD, 4, 0, 0}, 86 [R_386_TLS_TPOFF] = {0, FLG_RE_NOTREL, 4, 0, 0}, 87 [R_386_TLS_IE] = {0, FLG_RE_GOTADD | FLG_RE_TLSIE, 4, 0, 0}, 88 [R_386_TLS_GOTIE] = {0, FLG_RE_GOTADD | FLG_RE_TLSIE, 4, 0, 0}, 89 [R_386_TLS_LE] = {0, FLG_RE_TLSLE, 4, 0, 0}, 90 [R_386_TLS_GD] = {0, FLG_RE_GOTADD | FLG_RE_TLSGD, 4, 0, 0}, 91 [R_386_TLS_LDM] = {0, FLG_RE_GOTADD | FLG_RE_TLSLD, 4, 0, 0}, 92 [R_386_16] = {0, FLG_RE_NOTREL, 2, 0, 0}, 93 [R_386_PC16] = {0, FLG_RE_PCREL, 2, 0, 0}, 94 [R_386_8] = {0, FLG_RE_NOTREL, 1, 0, 0}, 95 [R_386_PC8] = {0, FLG_RE_PCREL, 1, 0, 0}, 96 [R_386_TLS_GD_32] = {0, FLG_RE_NOTSUP, 0, 0, 0}, 97 [R_386_TLS_GD_PUSH] = {0, FLG_RE_NOTSUP, 0, 0, 0}, 98 [R_386_TLS_GD_CALL] = {0, FLG_RE_NOTSUP, 0, 0, 0}, 99 [R_386_TLS_GD_POP] = {0, FLG_RE_NOTSUP, 0, 0, 0}, 100 [R_386_TLS_LDM_32] = {0, FLG_RE_NOTSUP, 0, 0, 0}, 101 [R_386_TLS_LDM_PUSH] = {0, FLG_RE_NOTSUP, 0, 0, 0}, 102 [R_386_TLS_LDM_CALL] = {0, FLG_RE_NOTSUP, 0, 0, 0}, 103 [R_386_TLS_LDM_POP] = {0, FLG_RE_NOTSUP, 0, 0, 0}, 104 [R_386_TLS_LDO_32] = {0, FLG_RE_TLSLD, 4, 0, 0}, 105 [R_386_TLS_IE_32] = {0, FLG_RE_NOTSUP, 0, 0, 0}, 106 [R_386_TLS_LE_32] = {0, FLG_RE_NOTSUP, 0, 0, 0}, 107 [R_386_TLS_DTPMOD32] = {0, FLG_RE_NOTREL, 4, 0, 0}, 108 [R_386_TLS_DTPOFF32] = {0, FLG_RE_NOTREL, 4, 0, 0}, 109 [R_386_TLS_TPOFF32] = {0, FLG_RE_NOTSUP, 0, 0, 0}, 110 [R_386_SIZE32] = {0, FLG_RE_SIZE | FLG_RE_VERIFY, 4, 0, 0}, 111 [R_386_TLS_GOTDESC] = {0, FLG_RE_NOTSUP, 0, 0, 0}, 112 [R_386_TLS_DESC_CALL] = {0, FLG_RE_NOTSUP, 0, 0, 0}, 113 [R_386_TLS_DESC] = {0, FLG_RE_NOTSUP, 0, 0, 0}, 114 [R_386_IRELATIVE] = {0, FLG_RE_NOTSUP, 0, 0, 0}, 115 [R_386_GOT32X] = {0, FLG_RE_GOTADD, 4, 0, 0}, 116 }; 117 #if (R_386_NUM != (R_386_GOT32X + 1)) 118 #error "R_386_NUM has grown" 119 #endif 120 121 /* 122 * Write a single relocated value to its reference location. 123 * We assume we wish to add the relocation amount, value, to the 124 * value of the address already present at the offset. 125 * 126 * NAME VALUE FIELD CALCULATION 127 * 128 * R_386_NONE 0 none none 129 * R_386_32 1 word32 S + A 130 * R_386_PC32 2 word32 S + A - P 131 * R_386_GOT32 3 word32 G + A - GOT / G + A 132 * R_386_PLT32 4 word32 L + A - P 133 * R_386_COPY 5 none none 134 * R_386_GLOB_DAT 6 word32 S 135 * R_386_JMP_SLOT 7 word32 S 136 * R_386_RELATIVE 8 word32 B + A 137 * R_386_GOTOFF 9 word32 S + A - GOT 138 * R_386_GOTPC 10 word32 GOT + A - P 139 * R_386_32PLT 11 word32 L + A 140 * R_386_TLS_GD_PLT 12 word32 @tlsgdplt 141 * R_386_TLS_LDM_PLT 13 word32 @tlsldmplt 142 * R_386_TLS_TPOFF 14 word32 @ntpoff(S) 143 * R_386_TLS_IE 15 word32 @indntpoff(S) 144 * R_386_TLS_GOTIE 16 word32 @gotntpoff(S) 145 * R_386_TLS_LE 17 word32 @ntpoff(S) 146 * R_386_TLS_GD 18 word32 @tlsgd(S) 147 * R_386_TLS_LDM 19 word32 @tlsldm(S) 148 * R_386_16 20 word16 S + A 149 * R_386_PC16 21 word16 S + A - P 150 * R_386_8 22 word8 S + A 151 * R_386_PC8 23 word8 S + A - P 152 * R_386_TLS_GD_32 24 word32 153 * R_386_TLS_GD_PUSH 25 word32 154 * R_386_TLS_GD_CALL 26 word32 155 * R_386_TLS_GD_POP 27 word32 156 * R_386_TLS_LDM_32 28 word32 157 * R_386_TLS_LDM_PUSH 29 word32 158 * R_386_TLS_LDM_CALL 30 word32 159 * R_386_TLS_LDM_POP 31 word32 160 * R_386_TLS_LDO_32 32 word32 @dtpoff(S) 161 * R_386_TLS_IE_32 33 word32 @gotpoff(S) 162 * R_386_TLS_LE_32 34 word32 @tpoff(S) 163 * R_386_TLS_DTPMOD32 35 word32 @dtpmod(S) 164 * R_386_TLS_DTPOFF32 36 word32 @dtpoff(S) 165 * R_386_TLS_TPOFF32 37 word32 166 * R_386_SIZE32 38 word32 Z + A 167 * R_386_TLS_GOTDESC 39 word32 168 * R_386_TLS_DESC_CALL 40 none none 169 * R_386_TLS_DESC 41 word32 170 * R_386_IRELATIVE 42 word32 indirect (B + A) 171 * R_386_GOT32X 43 word32 G + A - GOT / G + A 172 * 173 * Relocations are from Table 3.6: Relocation Types from the 386 psABI. 174 * (with reference also to the thread-local storage ABIs) 175 * 176 * Relocation calculations: 177 * 178 * CALCULATION uses the following notation: 179 * A the addend used 180 * B the base address of the shared object in memory 181 * G the offset into the global offset table 182 * GOT the address of teh global offset table 183 * L the procedure linkage entry 184 * P the place of the storage unit being relocated 185 * S the value of the symbol 186 * Z the size of the symbol whose index resides in the relocation 187 * entry 188 * 189 * @dtlndx(x): Allocate two contiguous entries in the GOT table to hold 190 * a Tls_index structure (for passing to __tls_get_addr()). The 191 * instructions referencing this entry will be bound to the first 192 * of the two GOT entries. 193 * 194 * @tmndx(x): Allocate two contiguous entries in the GOT table to hold 195 * a Tls_index structure (for passing to __tls_get_addr()). The 196 * ti_offset field of the Tls_index will be set to 0 (zero) and the 197 * ti_module will be filled in at run-time. The call to 198 * __tls_get_addr() will return the starting offset of the dynamic 199 * TLS block. 200 * 201 * @dtpoff(x): calculate the tlsoffset relative to the TLS block. 202 * 203 * @tpoff(x): calculate the tlsoffset relative to the TLS block. 204 * 205 * @dtpmod(x): calculate the module id of the object containing symbol x. 206 * 207 * The calculations in the CALCULATION column are assumed to have 208 * been performed before calling this function except for the addition of 209 * the addresses in the instructions. 210 */ 211 /* BEGIN CSTYLED */ 212 #if defined(DO_RELOC_LIBLD) 213 /*ARGSUSED5*/ 214 int 215 do_reloc_ld(Rel_desc *rdesc, uchar_t *off, Xword *value, 216 rel_desc_sname_func_t rel_desc_sname_func, 217 const char *file, int bswap, void *lml) 218 #else 219 int 220 do_reloc_rtld(uchar_t rtype, uchar_t *off, Xword *value, const char *sym, 221 const char *file, void *lml) 222 #endif 223 { 224 /* END CSTYLED */ 225 #ifdef DO_RELOC_LIBLD 226 #define sym (* rel_desc_sname_func)(rdesc) 227 uchar_t rtype = rdesc->rel_rtype; 228 #endif 229 const Rel_entry *rep; 230 231 rep = &reloc_table[rtype]; 232 233 switch (rep->re_fsize) { 234 case 1: 235 /* LINTED */ 236 *((uchar_t *)off) += (uchar_t)(*value); 237 break; 238 239 case 2: 240 #if defined(DORELOC_NATIVE) 241 /* LINTED */ 242 *((Half *)off) += (Half)(*value); 243 #else 244 { 245 Half v; 246 uchar_t *v_bytes = (uchar_t *)&v; 247 248 if (bswap) { 249 UL_ASSIGN_BSWAP_HALF(v_bytes, off); 250 v += *value; 251 UL_ASSIGN_BSWAP_HALF(off, v_bytes); 252 } else { 253 UL_ASSIGN_HALF(v_bytes, off); 254 v += *value; 255 UL_ASSIGN_HALF(off, v_bytes); 256 } 257 } 258 #endif 259 break; 260 261 case 4: 262 #if defined(DORELOC_NATIVE) 263 /* LINTED */ 264 *((Xword *)off) += *value; 265 #else 266 { 267 Word v; 268 uchar_t *v_bytes = (uchar_t *)&v; 269 270 if (bswap) { 271 UL_ASSIGN_BSWAP_WORD(v_bytes, off); 272 v += *value; 273 UL_ASSIGN_BSWAP_WORD(off, v_bytes); 274 } else { 275 UL_ASSIGN_WORD(v_bytes, off); 276 v += *value; 277 UL_ASSIGN_WORD(off, v_bytes); 278 } 279 } 280 #endif 281 break; 282 default: 283 /* 284 * To keep chkmsg() happy: MSG_INTL(MSG_REL_UNSUPSZ) 285 */ 286 REL_ERR_UNSUPSZ(lml, file, sym, rtype, rep->re_fsize); 287 return (0); 288 } 289 return (1); 290 291 #ifdef DO_RELOC_LIBLD 292 #undef sym 293 #endif 294 } 295