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) 1988 AT&T 24 * All Rights Reserved 25 * 26 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 27 * Use is subject to license terms. 28 */ 29 #pragma ident "%Z%%M% %I% %E% SMI" 30 31 /* 32 * ld -- link/editor main program 33 */ 34 #include <sys/types.h> 35 #include <sys/mman.h> 36 #include <string.h> 37 #include <stdio.h> 38 #include <locale.h> 39 #include <stdarg.h> 40 #include <debug.h> 41 #include "msg.h" 42 #include "_libld.h" 43 44 /* 45 * A default library search path is used if one was not supplied on the command 46 * line. Note: these strings can not use MSG_ORIG() since they are modified as 47 * part of the path processing. 48 */ 49 #if defined(_ELF64) 50 static char def_Plibpath[] = "/lib/64:/usr/lib/64"; 51 #else 52 static char def_Plibpath[] = "/usr/ccs/lib:/lib:/usr/lib"; 53 #endif 54 55 /* 56 * A default elf header provides for simplifying diagnostic processing. 57 */ 58 static Ehdr def_ehdr = { { ELFMAG0, ELFMAG1, ELFMAG2, ELFMAG3, 59 M_CLASS, M_DATA }, 0, M_MACH, EV_CURRENT }; 60 61 /* 62 * The main program 63 */ 64 int 65 ld_main(int argc, char **argv) 66 { 67 char *sgs_support; /* SGS_SUPPORT environment string */ 68 Half etype; 69 int suplib = 0; 70 Ofl_desc *ofl; 71 72 /* 73 * Initialize signal handlers, and output file variables. Establish a 74 * default output ELF header to satisfy diagnostic requirements. 75 */ 76 if ((ofl = libld_calloc(1, sizeof (Ofl_desc))) == 0) 77 return (1); 78 79 ofl->ofl_dehdr = &def_ehdr; 80 81 ld_init(ofl); 82 83 /* 84 * Build up linker version string 85 */ 86 if ((ofl->ofl_sgsid = (char *)libld_calloc(MSG_SGS_ID_SIZE + 87 strlen(link_ver_string) + 1, 1)) == NULL) 88 return (1); 89 (void) strcpy(ofl->ofl_sgsid, MSG_ORIG(MSG_SGS_ID)); 90 (void) strcat(ofl->ofl_sgsid, link_ver_string); 91 92 /* 93 * Argument pass one. Get all the input flags (skip any files) and 94 * check for consistency. After this point any map file processing 95 * would have been completed and the entrance criteria and segment 96 * descriptor lists will be complete. 97 */ 98 if (ld_process_flags(ofl, argc, argv) == S_ERROR) 99 return (1); 100 if (ofl->ofl_flags & FLG_OF_FATAL) { 101 eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_ARG_FLAGS)); 102 return (1); 103 } 104 105 /* 106 * At this point a call such as ld -V is considered complete. 107 */ 108 if (ofl->ofl_flags1 & FLG_OF1_DONE) 109 return (0); 110 111 /* 112 * Determine whether any support libraries been loaded (either through 113 * the SGS_SUPPORT environment variable and/or through the -S option). 114 * By default the support library libldstab.so.1 is loaded provided the 115 * user hasn't specified their own -S libraries. 116 */ 117 #if defined(_LP64) 118 if ((sgs_support = getenv(MSG_ORIG(MSG_SGS_SUPPORT_64))) == NULL) 119 #else 120 if ((sgs_support = getenv(MSG_ORIG(MSG_SGS_SUPPORT_32))) == NULL) 121 #endif 122 sgs_support = getenv(MSG_ORIG(MSG_SGS_SUPPORT)); 123 124 if (sgs_support && (*sgs_support != '\0')) { 125 const char *sep = MSG_ORIG(MSG_STR_COLON); 126 char *lib; 127 char *lasts; 128 129 DBG_CALL(Dbg_support_req(ofl->ofl_lml, sgs_support, 130 DBG_SUP_ENVIRON)); 131 if ((lib = strtok_r(sgs_support, sep, &lasts)) != NULL) { 132 do { 133 if (strcmp(lib, 134 MSG_ORIG(MSG_FIL_LIBSTAB)) == 0) { 135 if (suplib++) 136 continue; 137 } 138 if (ld_sup_loadso(ofl, lib) == S_ERROR) 139 return (ld_exit(ofl)); 140 141 } while ((lib = strtok_r(NULL, sep, &lasts)) != NULL); 142 } 143 DBG_CALL(Dbg_util_nl(ofl->ofl_lml, DBG_NL_STD)); 144 } 145 if (lib_support.head) { 146 Listnode *lnp; 147 char *lib; 148 149 for (LIST_TRAVERSE(&lib_support, lnp, lib)) { 150 DBG_CALL(Dbg_support_req(ofl->ofl_lml, lib, 151 DBG_SUP_CMDLINE)); 152 if (ld_sup_loadso(ofl, lib) == S_ERROR) 153 return (ld_exit(ofl)); 154 } 155 DBG_CALL(Dbg_util_nl(ofl->ofl_lml, DBG_NL_STD)); 156 } else { 157 if (suplib == 0) { 158 DBG_CALL(Dbg_support_req(ofl->ofl_lml, 159 MSG_ORIG(MSG_FIL_LIBSTAB), DBG_SUP_DEFAULT)); 160 if (ld_sup_loadso(ofl, MSG_ORIG(MSG_FIL_LIBSTAB)) == 161 S_ERROR) 162 return (ld_exit(ofl)); 163 } 164 DBG_CALL(Dbg_util_nl(ofl->ofl_lml, DBG_NL_STD)); 165 } 166 167 DBG_CALL(Dbg_ent_print(ofl->ofl_lml, ofl->ofl_dehdr->e_machine, 168 &ofl->ofl_ents, (ofl->ofl_flags & FLG_OF_DYNAMIC))); 169 DBG_CALL(Dbg_seg_list(ofl->ofl_lml, ofl->ofl_dehdr->e_machine, 170 &ofl->ofl_segs)); 171 172 /* 173 * The objscnt and soscnt variables were used to estimate the expected 174 * input files, and size the symbol hash buckets accordingly. Reset 175 * these values now, so as to gain an accurate count from pass two, for 176 * later statistics diagnostics. 177 */ 178 ofl->ofl_objscnt = ofl->ofl_soscnt = 0; 179 180 /* 181 * Determine whether we can create the file before going any further. 182 */ 183 if (ld_open_outfile(ofl) == S_ERROR) 184 return (ld_exit(ofl)); 185 186 /* 187 * If the user didn't supply a library path supply a default. And, if 188 * no run-path has been specified (-R), see if the environment variable 189 * is in use (historic). Also assign a default starting address. 190 * Don't use MSG_ORIG() for these strings, they're written to later. 191 */ 192 if (Plibpath == NULL) 193 Plibpath = def_Plibpath; 194 195 if (ofl->ofl_rpath == NULL) { 196 char *rpath; 197 if (((rpath = getenv(MSG_ORIG(MSG_LD_RUN_PATH))) != NULL) && 198 (strcmp((const char *)rpath, MSG_ORIG(MSG_STR_EMPTY)))) 199 ofl->ofl_rpath = rpath; 200 } 201 if (ofl->ofl_flags & FLG_OF_EXEC) 202 ofl->ofl_segorigin = M_SEGM_ORIGIN; 203 204 /* 205 * Argument pass two. Input all libraries and objects. 206 */ 207 if (ld_lib_setup(ofl) == S_ERROR) 208 return (ld_exit(ofl)); 209 210 /* 211 * Call ld_start() with the etype of our output file and the 212 * output file name. 213 */ 214 if (ofl->ofl_flags & FLG_OF_SHAROBJ) 215 etype = ET_DYN; 216 else if (ofl->ofl_flags & FLG_OF_RELOBJ) 217 etype = ET_REL; 218 else 219 etype = ET_EXEC; 220 221 ld_sup_start(ofl, etype, argv[0]); 222 223 /* 224 * Process all input files. 225 */ 226 if (ld_process_files(ofl, argc, argv) == S_ERROR) 227 return (ld_exit(ofl)); 228 if (ofl->ofl_flags & FLG_OF_FATAL) { 229 eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_ARG_FILES), 230 ofl->ofl_name); 231 return (ld_exit(ofl)); 232 } 233 234 ld_sup_input_done(ofl); 235 236 /* 237 * If there were any partially initialized symbol, 238 * do preparation works. 239 */ 240 if (ofl->ofl_ismove.head != 0) { 241 if (ld_sunwmove_preprocess(ofl) == S_ERROR) 242 return (ld_exit(ofl)); 243 } 244 245 /* 246 * Before validating all symbols count the number of relocation entries. 247 * If copy relocations exist, COMMON symbols must be generated which are 248 * assigned to the executables .bss. During sym_validate() the actual 249 * size and alignment of the .bss is calculated. Doing things in this 250 * order reduces the number of symbol table traversals required (however 251 * it does take a little longer for the user to be told of any undefined 252 * symbol errors). 253 */ 254 if (ld_reloc_init(ofl) == S_ERROR) 255 return (ld_exit(ofl)); 256 257 /* 258 * Now that all symbol processing is complete see if any undefined 259 * references still remain. If we observed undefined symbols the 260 * FLG_OF_FATAL bit will be set: If creating a static executable, or a 261 * dynamic executable or shared object with the -zdefs flag set, this 262 * condition is fatal. If creating a shared object with the -Bsymbolic 263 * flag set, this condition is simply a warning. 264 */ 265 if (ld_sym_validate(ofl) == S_ERROR) 266 return (ld_exit(ofl)); 267 268 if (ofl->ofl_flags1 & FLG_OF1_OVRFLW) { 269 eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_ARG_FILES), 270 ofl->ofl_name); 271 return (ld_exit(ofl)); 272 } else if (ofl->ofl_flags & FLG_OF_FATAL) { 273 eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_ARG_SYM_FATAL), 274 ofl->ofl_name); 275 return (ld_exit(ofl)); 276 } else if (ofl->ofl_flags & FLG_OF_WARN) 277 eprintf(ofl->ofl_lml, ERR_WARNING, MSG_INTL(MSG_ARG_SYM_WARN)); 278 279 /* 280 * Generate any necessary sections. 281 */ 282 if (ld_make_sections(ofl) == S_ERROR) 283 return (ld_exit(ofl)); 284 285 /* 286 * Now that all sections have been added to the output file, check to 287 * see if any section ordering was specified and if so give a warning 288 * if any ordering directives were not matched. 289 * Also, if SHF_ORDERED sections exist, set up sort key values. 290 */ 291 ld_sec_validate(ofl); 292 293 /* 294 * Having collected all the input data create the initial output file 295 * image, assign virtual addresses to the image, and generate a load 296 * map if the user requested one. 297 */ 298 if (ld_create_outfile(ofl) == S_ERROR) 299 return (ld_exit(ofl)); 300 301 if (ld_update_outfile(ofl) == S_ERROR) 302 return (ld_exit(ofl)); 303 if (ofl->ofl_flags & FLG_OF_GENMAP) 304 ld_map_out(ofl); 305 306 /* 307 * Build relocation sections and perform any relocation updates. 308 */ 309 if (ld_reloc_process(ofl) == S_ERROR) 310 return (ld_exit(ofl)); 311 312 #if defined(__x86) && defined(_ELF64) 313 /* 314 * Fill in contents for Unwind Header 315 */ 316 if (populate_amd64_unwindhdr(ofl) == S_ERROR) 317 return (ld_exit(ofl)); 318 #endif 319 /* 320 * Finally create the files elf checksum. 321 */ 322 if (ofl->ofl_checksum) 323 *ofl->ofl_checksum = (Xword)elf_checksum(ofl->ofl_elf); 324 325 /* 326 * We're done, so make sure the updates are flushed to the output file. 327 */ 328 if ((ofl->ofl_size = elf_update(ofl->ofl_welf, ELF_C_WRITE)) == 0) { 329 eprintf(ofl->ofl_lml, ERR_ELF, MSG_INTL(MSG_ELF_UPDATE), 330 ofl->ofl_name); 331 return (ld_exit(ofl)); 332 } 333 334 ld_sup_atexit(ofl, 0); 335 336 DBG_CALL(Dbg_statistics_ld(ofl)); 337 338 /* 339 * For performance reasons we don't actually free up the memory we've 340 * allocated, it will be freed when we exit. 341 * 342 * But the below line can be uncommented if/when we want to measure how 343 * our memory consumption and freeing are doing. We should be able to 344 * free all the memory that has been allocated as part of the link-edit 345 * process. 346 * 347 * ofl_cleanup(ofl); 348 */ 349 return (0); 350 } 351 352 /* 353 * Cleanup an Ifl_desc. 354 */ 355 static void 356 ifl_list_cleanup(List *ifl_list) 357 { 358 Listnode *lnp; 359 Ifl_desc *ifl; 360 361 for (LIST_TRAVERSE(ifl_list, lnp, ifl)) 362 if (ifl->ifl_elf) 363 (void) elf_end(ifl->ifl_elf); 364 ifl_list->head = 0; 365 ifl_list->tail = 0; 366 } 367 368 /* 369 * Cleanup all memory that has been dynamically allocated during libld 370 * processing and elf_end() all Elf descriptors that are still open. 371 */ 372 void 373 ld_ofl_cleanup(Ofl_desc *ofl) 374 { 375 Ld_heap *chp, *php; 376 Ar_desc *adp; 377 Listnode *lnp; 378 379 ifl_list_cleanup(&ofl->ofl_objs); 380 ifl_list_cleanup(&ofl->ofl_sos); 381 382 for (LIST_TRAVERSE(&ofl->ofl_ars, lnp, adp)) { 383 Ar_aux *aup; 384 Elf_Arsym *arsym; 385 386 for (arsym = adp->ad_start, aup = adp->ad_aux; 387 arsym->as_name; ++arsym, ++aup) { 388 if ((aup->au_mem) && (aup->au_mem != FLG_ARMEM_PROC)) { 389 (void) elf_end(aup->au_mem->am_elf); 390 391 /* 392 * Null out all entries to this member so 393 * that we don't attempt to elf_end() it again. 394 */ 395 ld_ar_member(adp, arsym, aup, 0); 396 } 397 } 398 (void) elf_end(adp->ad_elf); 399 } 400 401 (void) elf_end(ofl->ofl_elf); 402 (void) elf_end(ofl->ofl_welf); 403 404 for (chp = ld_heap, php = 0; chp; php = chp, chp = chp->lh_next) { 405 if (php) 406 (void) munmap((void *)php, 407 (size_t)php->lh_end - (size_t)php); 408 } 409 if (php) 410 (void) munmap((void *)php, (size_t)php->lh_end - (size_t)php); 411 412 ld_heap = 0; 413 } 414