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) 2004, 2010, Oracle and/or its affiliates. All rights reserved. 24 */ 25 26 #if defined(_KERNEL) 27 #include <sys/types.h> 28 #include "reloc.h" 29 #else 30 #define ELF_TARGET_AMD64 31 #if defined(DO_RELOC_LIBLD) 32 #undef DO_RELOC_LIBLD 33 #define DO_RELOC_LIBLD_X86 34 #endif 35 #include <stdio.h> 36 #include "sgs.h" 37 #include "machdep.h" 38 #include "libld.h" 39 #include "reloc.h" 40 #include "conv.h" 41 #include "msg.h" 42 #endif 43 44 /* 45 * We need to build this code differently when it is used for 46 * cross linking: 47 * - Data alignment requirements can differ from those 48 * of the running system, so we can't access data 49 * in units larger than a byte 50 * - We have to include code to do byte swapping when the 51 * target and linker host use different byte ordering, 52 * but such code is a waste when running natively. 53 */ 54 #if !defined(DO_RELOC_LIBLD) || defined(__i386) || defined(__amd64) 55 #define DORELOC_NATIVE 56 #endif 57 58 /* 59 * This table represents the current relocations that do_reloc() is able to 60 * process. The relocations below that are marked SPECIAL are relocations that 61 * take special processing and shouldn't actually ever be passed to do_reloc(). 62 */ 63 const Rel_entry reloc_table[R_AMD64_NUM] = { 64 /* R_AMD64_NONE */ {0, FLG_RE_NOTREL, 0, 0, 0}, 65 /* R_AMD64_64 */ {0, FLG_RE_NOTREL, 8, 0, 0}, 66 /* R_AMD64_PC32 */ {0, FLG_RE_PCREL, 4, 0, 0}, 67 /* R_AMD64_GOT32 */ {0, FLG_RE_NOTSUP, 0, 0, 0}, 68 /* R_AMD64_PLT32 */ {0, FLG_RE_PCREL | FLG_RE_PLTREL | 69 FLG_RE_VERIFY | FLG_RE_SIGN, 4, 0, 0}, 70 /* R_AMD64_COPY */ {0, FLG_RE_NOTSUP, 0, 0, 0}, /* SPECIAL */ 71 /* R_AMD64_GLOB_DAT */ {0, FLG_RE_NOTREL, 8, 0, 0}, 72 /* R_AMD64_JUMP_SLOT */ {0, FLG_RE_NOTSUP, 0, 0, 0}, /* SPECIAL */ 73 /* R_AMD64_RELATIVE */ {0, FLG_RE_NOTREL, 8, 0, 0}, 74 /* R_AMD64_GOTPCREL */ {0, FLG_RE_GOTPC | FLG_RE_GOTADD, 4, 0, 0}, 75 /* R_AMD64_32 */ {0, FLG_RE_NOTREL, 4, 0, 0}, 76 /* R_AMD64_32S */ {0, FLG_RE_NOTREL, 4, 0, 0}, 77 /* R_AMD64_16 */ {0, FLG_RE_NOTREL, 2, 0, 0}, 78 /* R_AMD64_PC16 */ {0, FLG_RE_PCREL, 2, 0, 0}, 79 /* R_AMD64_8 */ {0, FLG_RE_NOTREL, 1, 0, 0}, 80 /* R_AMD64_PC8 */ {0, FLG_RE_PCREL, 1, 0, 0}, 81 /* R_AMD64_DTPMOD64 */ {0, FLG_RE_NOTREL, 8, 0, 0}, 82 /* R_AMD64_DTPOFF64 */ {0, FLG_RE_NOTREL, 8, 0, 0}, 83 /* R_AMD64_TPOFF64 */ {0, FLG_RE_NOTREL, 8, 0, 0}, 84 /* R_AMD64_TLSGD */ {0, FLG_RE_GOTPC | FLG_RE_GOTADD | FLG_RE_TLSGD, 85 4, 0, 0}, 86 /* R_AMD64_TLSLD */ {0, FLG_RE_GOTPC | FLG_RE_GOTADD | FLG_RE_TLSLD, 87 4, 0, 0}, 88 /* R_AMD64_DTPOFF32 */ {0, FLG_RE_TLSLD, 4}, 89 /* R_AMD64_GOTTPOFF */ {0, FLG_RE_GOTPC | FLG_RE_GOTADD | FLG_RE_TLSIE, 90 4, 0, 0}, 91 /* R_AMD64_TPOFF32 */ {0, FLG_RE_TLSLE, 4, 0, 0}, 92 /* R_AMD64_PC64 */ {0, FLG_RE_PCREL, 8, 0, 0}, 93 /* R_AMD64_GOTOFF64 */ {0, FLG_RE_GOTREL, 8, 0, 0}, 94 /* R_AMD64_GOTPC32 */ {0, FLG_RE_PCREL | FLG_RE_GOTPC | FLG_RE_LOCLBND, 95 4, 0, 0}, 96 /* R_AMD64_GOT64 */ {0, FLG_RE_NOTSUP, 0, 0, 0}, 97 /* R_AMD64_GOTPCREL64 */ {FLG_RE_NOTSUP, 0, 0, 0}, 98 /* R_AMD64_GOTPC6 */ {0, FLG_RE_NOTSUP, 0, 0, 0}, 99 /* R_AMD64_GOTPLT64 */ {0, FLG_RE_NOTSUP, 0, 0, 0}, 100 /* R_AMD64_PLTOFF64 */ {0, FLG_RE_NOTSUP, 0, 0, 0}, 101 /* R_AMD64_SIZE32 */ {0, FLG_RE_SIZE, 4, 0, 0}, 102 /* R_AMD64_SIZE64 */ {0, FLG_RE_SIZE, 8, 0, 0} 103 }; 104 #if (R_AMD64_NUM != (R_AMD64_SIZE64 + 1)) 105 #error "R_AMD64_NUM has grown" 106 #endif 107 108 /* 109 * Write a single relocated value to its reference location. 110 * We assume we wish to add the relocation amount, value, to the 111 * value of the address already present at the offset. 112 * 113 * NAME VALUE FIELD CALCULATION 114 * 115 * R_AMD64_NONE 0 none none 116 * R_AMD64_64 1 word64 S + A 117 * R_AMD64_PC32 2 word64 S + A 118 * R_AMD64_GOT32 3 word32 G + A 119 * R_AMD64_PLT32 4 word32 L + A - P 120 * R_AMD64_COPY 5 none none 121 * R_AMD64_GLOB_DAT 6 word64 S 122 * R_AMD64_JUMP_SLOT 7 word64 S 123 * R_AMD64_RELATIVE 8 word64 B + A 124 * R_AMD64_GOTPCREL 9 word32 G + GOT + A - P 125 * R_AMD64_32 10 word32 S + A 126 * R_AMD64_32S 11 word32 S + A 127 * R_AMD64_16 12 word16 S + A 128 * R_AMD64_PC16 13 word16 S + A - P 129 * R_AMD64_8 14 word8 S + A 130 * R_AMD64_PC8 15 word8 S + A - P 131 * R_AMD64_DTPMOD64 16 word64 132 * R_AMD64_DTPOFF64 17 word64 133 * R_AMD64_TPOFF64 18 word64 134 * R_AMD64_TLSGD 19 word32 135 * R_AMD64_TLSLD 20 word32 136 * R_AMD64_DTPOFF32 21 word32 137 * R_AMD64_GOTTPOFF 22 word32 138 * R_AMD64_TPOFF32 23 word32 139 * R_AMD64_PC64 24 word32 S + A - P 140 * R_AMD64_GOTOFF64 25 word32 S + A - GOT 141 * R_AMD64_GOTPC32 26 word32 GOT + A - P 142 * R_AMD64_GOT64 27 reserved for future expansion 143 * R_AMD64_GOTPCREL64 28 reserved for future expansion 144 * R_AMD64_GOTPC64 29 reserved for future expansion 145 * R_AMD64_GOTPLT64 30 reserved for future expansion 146 * R_AMD64_PLTOFF64 31 reserved for future expansion 147 * R_AMD64_SIZE32 32 word32 Z + A 148 * R_AMD64_SIZE64 33 word64 Z + A 149 * 150 * Relocation calculations: 151 * A Represents the addend used to compute the value of the 152 * relocatable field. 153 * 154 * B Represents the base address at which a shared objects has 155 * been loaded into memory during executaion. Generally, a 156 * shared objects is built with a 0 base virtual address, 157 * but the execution address will be different. 158 * 159 * G Represents the offset into the global offset table 160 * at which the relocation entry's symbol will reside 161 * during execution. 162 * 163 * GOT Rrepresents the address of the global offset table. 164 * 165 * L Represents the place (section offset or address) of 166 * the Procedure Linkage Table entry for a symbol. 167 * 168 * P Represents the place (section offset or address) of the 169 * storage unit being relocated (computed using r_offset). 170 * 171 * S Represents the value of the symbol whose index resides 172 * in the relocation entry. 173 * 174 * Z the size of the symbol whose index resides in the relocation 175 * entry 176 */ 177 178 179 /* 180 * Bits that must be cleared or identical for a value to act as if extended in 181 * the given way. 182 */ 183 #define ZEROEXBITS 0xffffffff00000000ULL 184 #define SIGNEXBITS 0xffffffff80000000ULL 185 186 #if defined(_KERNEL) 187 #define lml 0 /* Needed by arglist of REL_ERR_* macros */ 188 int 189 do_reloc_krtld(uchar_t rtype, uchar_t *off, Xword *value, const char *sym, 190 const char *file) 191 #elif defined(DO_RELOC_LIBLD) 192 /*ARGSUSED5*/ 193 int 194 do_reloc_ld(Rel_desc *rdesc, uchar_t *off, Xword *value, 195 rel_desc_sname_func_t rel_desc_sname_func, 196 const char *file, int bswap, void *lml) 197 #else 198 int 199 do_reloc_rtld(uchar_t rtype, uchar_t *off, Xword *value, const char *sym, 200 const char *file, void *lml) 201 #endif 202 { 203 #ifdef DO_RELOC_LIBLD 204 #define sym (* rel_desc_sname_func)(rdesc) 205 uchar_t rtype = rdesc->rel_rtype; 206 #endif 207 const Rel_entry *rep; 208 209 rep = &reloc_table[rtype]; 210 211 switch (rep->re_fsize) { 212 case 1: 213 /* LINTED */ 214 *((uchar_t *)off) = (uchar_t)(*value); 215 break; 216 217 case 2: 218 #if defined(DORELOC_NATIVE) 219 /* LINTED */ 220 *((Half *)off) = (Half)(*value); 221 #else 222 { 223 Half v = (Half)(*value); 224 uchar_t *v_bytes = (uchar_t *)&v; 225 226 if (bswap) { 227 UL_ASSIGN_BSWAP_HALF(off, v_bytes); 228 } else { 229 UL_ASSIGN_HALF(off, v_bytes); 230 } 231 } 232 #endif 233 break; 234 235 case 4: 236 /* 237 * The amd64 psABI requires that we perform the following 238 * verifications: 239 * 240 * The R_AMD64_32 and R_AMD64_32S relocations truncate the 241 * computed value to 32bits. Verify that the generated value 242 * for the R_AMD64_32/32S relocation zero-extends (sign 243 * extends) to the original 64-bit value. 244 * 245 * Also, the following relocations are all 32 bit PC relative 246 * references. Validate that the value being written will fit 247 * in the field provided. 248 * 249 * R_AMD64_PC32, R_AMD64_GOTPC32, R_AMD64_GOTPCREL 250 */ 251 if (rtype == R_AMD64_32) { 252 /* 253 * Verify that this value will act as a zero-extended 254 * unsigned 32 bit value. That is, that the upper 255 * 32 bits are zero. 256 */ 257 if ((*value & ZEROEXBITS) != 0) { 258 /* 259 * To keep chkmsg() happy: 260 * MSG_INTL(MSG_REL_NOFIT) 261 */ 262 REL_ERR_NOFIT(lml, file, sym, rtype, *value); 263 return (0); 264 } 265 } else if ((rtype == R_AMD64_32S) || (rtype == R_AMD64_PC32) || 266 (rtype == R_AMD64_GOTPCREL) || (rtype == R_AMD64_GOTPC32)) { 267 /* 268 * Verify that this value will act as a sign-extended 269 * signed 32 bit value, that is that the upper 33 bits 270 * are either all zero or all one. 271 */ 272 if (((*value & SIGNEXBITS) != SIGNEXBITS) && 273 ((*value & SIGNEXBITS) != 0)) { 274 /* 275 * To keep chkmsg() happy: 276 * MSG_INTL(MSG_REL_NOFIT) 277 */ 278 REL_ERR_NOFIT(lml, file, sym, rtype, *value); 279 return (0); 280 } 281 } 282 283 #if defined(DORELOC_NATIVE) 284 /* LINTED */ 285 *((Word *)off) += *value; 286 #else 287 { 288 Word v; 289 uchar_t *v_bytes = (uchar_t *)&v; 290 291 if (bswap) { 292 UL_ASSIGN_BSWAP_WORD(v_bytes, off); 293 v += *value; 294 UL_ASSIGN_BSWAP_WORD(off, v_bytes); 295 } else { 296 UL_ASSIGN_WORD(v_bytes, off); 297 v += *value; 298 UL_ASSIGN_WORD(off, v_bytes); 299 } 300 } 301 #endif 302 break; 303 304 case 8: 305 #if defined(DORELOC_NATIVE) 306 /* LINTED */ 307 *((Xword *)off) += *value; 308 #else 309 { 310 Xword v; 311 uchar_t *v_bytes = (uchar_t *)&v; 312 313 if (bswap) { 314 UL_ASSIGN_BSWAP_XWORD(v_bytes, off); 315 v += *value; 316 UL_ASSIGN_BSWAP_XWORD(off, v_bytes); 317 } else { 318 UL_ASSIGN_XWORD(v_bytes, off); 319 v += *value; 320 UL_ASSIGN_XWORD(off, v_bytes); 321 } 322 } 323 #endif 324 break; 325 default: 326 /* 327 * To keep chkmsg() happy: MSG_INTL(MSG_REL_UNSUPSZ) 328 */ 329 REL_ERR_UNSUPSZ(lml, file, sym, rtype, rep->re_fsize); 330 return (0); 331 } 332 return (1); 333 334 #ifdef DO_RELOC_LIBLD 335 #undef sym 336 #endif 337 } 338