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 2008 Sun Microsystems, Inc. All rights reserved. 27 * Use is subject to license terms. 28 */ 29 30 /* 31 * This file contains the functions responsible for opening the output file 32 * image, associating the appropriate input elf structures with the new image, 33 * and obtaining new elf structures to define the new image. 34 */ 35 #include <stdio.h> 36 #include <sys/stat.h> 37 #include <fcntl.h> 38 #include <link.h> 39 #include <errno.h> 40 #include <string.h> 41 #include <limits.h> 42 #include <debug.h> 43 #include <unistd.h> 44 #include "msg.h" 45 #include "_libld.h" 46 47 /* 48 * Determine a least common multiplier. Input sections contain an alignment 49 * requirement, which elf_update() uses to insure that the section is aligned 50 * correctly off of the base of the elf image. We must also insure that the 51 * sections mapping is congruent with this alignment requirement. For each 52 * input section associated with a loadable segment determine whether the 53 * segments alignment must be adjusted to compensate for a sections alignment 54 * requirements. 55 */ 56 Xword 57 ld_lcm(Xword a, Xword b) 58 { 59 Xword _r, _a, _b; 60 61 if ((_a = a) == 0) 62 return (b); 63 if ((_b = b) == 0) 64 return (a); 65 66 if (_a > _b) 67 _a = b, _b = a; 68 while ((_r = _b % _a) != 0) 69 _b = _a, _a = _r; 70 return ((a / _a) * b); 71 } 72 73 /* 74 * Open the output file and insure the correct access modes. 75 */ 76 uintptr_t 77 ld_open_outfile(Ofl_desc * ofl) 78 { 79 mode_t mode; 80 struct stat status; 81 82 /* 83 * Determine the required file mode from the type of output file we 84 * are creating. 85 */ 86 mode = (ofl->ofl_flags & (FLG_OF_EXEC | FLG_OF_SHAROBJ)) 87 ? 0777 : 0666; 88 89 /* Determine if the output file already exists */ 90 if (stat(ofl->ofl_name, &status) == 0) { 91 if ((status.st_mode & S_IFMT) != S_IFREG) { 92 /* 93 * It is not a regular file, so don't delete it 94 * or allow it to be deleted. This allows root 95 * users to specify /dev/null output file for 96 * verification links. 97 */ 98 ofl->ofl_flags1 |= FLG_OF1_NONREG; 99 } else { 100 /* 101 * It's a regular file, so unlink it. In standard 102 * Unix fashion, the old file will continue to 103 * exist until its link count drops to 0 and no 104 * process has the file open. In the meantime, we 105 * create a new file (inode) under the same name, 106 * available for new use. 107 * 108 * The advantage of this policy is that creating 109 * a new executable or sharable library does not 110 * corrupt existing processes using the old file. 111 * A possible disadvantage is that if the existing 112 * file has a (link_count > 1), the other names will 113 * continue to reference the old inode, thus 114 * breaking the link. 115 * 116 * A subtlety here is that POSIX says we are not 117 * supposed to replace a non-writable file, which 118 * is something that unlink() is happy to do. The 119 * only 100% reliable test against this is to open 120 * the file for non-destructive write access. If the 121 * open succeeds, we are clear to unlink it, and if 122 * not, then the error generated is the error we 123 * need to report. 124 */ 125 if ((ofl->ofl_fd = open(ofl->ofl_name, O_RDWR, 126 mode)) < 0) { 127 int err = errno; 128 129 if (err != ENOENT) { 130 eprintf(ofl->ofl_lml, ERR_FATAL, 131 MSG_INTL(MSG_SYS_OPEN), 132 ofl->ofl_name, strerror(err)); 133 return (S_ERROR); 134 } 135 } else { 136 (void) close(ofl->ofl_fd); 137 } 138 139 if ((unlink(ofl->ofl_name) == -1) && 140 (errno != ENOENT)) { 141 int err = errno; 142 143 eprintf(ofl->ofl_lml, ERR_FATAL, 144 MSG_INTL(MSG_SYS_UNLINK), 145 ofl->ofl_name, strerror(err)); 146 return (S_ERROR); 147 } 148 } 149 } 150 151 /* 152 * Open (or create) the output file name (ofl_fd acts as a global 153 * flag to ldexit() signifying whether the output file should be 154 * removed or not on error). 155 */ 156 if ((ofl->ofl_fd = open(ofl->ofl_name, O_RDWR | O_CREAT | O_TRUNC, 157 mode)) < 0) { 158 int err = errno; 159 160 eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_SYS_OPEN), 161 ofl->ofl_name, strerror(err)); 162 return (S_ERROR); 163 } 164 165 return (1); 166 } 167 168 169 /* 170 * If we are creating a memory model we need to update the present memory image. 171 * First we need to call elf_update(ELF_C_NULL) which will calculate the offsets 172 * of each section and its associated data buffers. From this information we 173 * can then determine what padding is required. 174 * Two actions are necessary to convert the present disc image into a memory 175 * image: 176 * 177 * o Loadable segments must be padded so that the next segments virtual 178 * address and file offset are the same. 179 * 180 * o NOBITS sections must be converted into allocated, null filled sections. 181 */ 182 static uintptr_t 183 pad_outfile(Ofl_desc *ofl) 184 { 185 Listnode *lnp; 186 off_t offset; 187 Elf_Scn *oscn = 0; 188 Sg_desc *sgp; 189 Ehdr *ehdr; 190 191 /* 192 * Update all the elf structures. This will assign offsets to the 193 * section headers and data buffers as they relate to the new image. 194 */ 195 if (elf_update(ofl->ofl_welf, ELF_C_NULL) == -1) { 196 eprintf(ofl->ofl_lml, ERR_ELF, MSG_INTL(MSG_ELF_UPDATE), 197 ofl->ofl_name); 198 return (S_ERROR); 199 } 200 if ((ehdr = elf_getehdr(ofl->ofl_welf)) == NULL) { 201 eprintf(ofl->ofl_lml, ERR_ELF, MSG_INTL(MSG_ELF_GETEHDR), 202 ofl->ofl_name); 203 return (S_ERROR); 204 } 205 206 /* 207 * Initialize the offset by skipping the Elf header and program 208 * headers. 209 */ 210 offset = ehdr->e_phoff + (ehdr->e_phnum * ehdr->e_phentsize); 211 212 /* 213 * Traverse the segment list looking for loadable segments. 214 */ 215 for (LIST_TRAVERSE(&ofl->ofl_segs, lnp, sgp)) { 216 Phdr *phdr = &(sgp->sg_phdr); 217 Os_desc *osp; 218 Aliste idx; 219 220 /* 221 * If we've already processed a loadable segment, the `scn' 222 * variable will be initialized to the last section that was 223 * part of that segment. Add sufficient padding to this section 224 * to cause the next segments virtual address and file offset to 225 * be the same. 226 */ 227 if (oscn && (phdr->p_type == PT_LOAD)) { 228 Elf_Data * data; 229 size_t size; 230 231 size = (size_t)(S_ROUND(offset, phdr->p_align) - 232 offset); 233 234 if ((data = elf_newdata(oscn)) == NULL) { 235 eprintf(ofl->ofl_lml, ERR_ELF, 236 MSG_INTL(MSG_ELF_NEWDATA), ofl->ofl_name); 237 return (S_ERROR); 238 } 239 if ((data->d_buf = libld_calloc(size, 1)) == 0) 240 return (S_ERROR); 241 242 data->d_type = ELF_T_BYTE; 243 data->d_size = size; 244 data->d_align = 1; 245 data->d_version = ofl->ofl_dehdr->e_version; 246 } 247 248 /* 249 * Traverse the output sections for this segment calculating the 250 * offset of each section. Retain the final section descriptor 251 * as this will be where any padding buffer will be added. 252 */ 253 for (APLIST_TRAVERSE(sgp->sg_osdescs, idx, osp)) { 254 Shdr *shdr = osp->os_shdr; 255 256 offset = (off_t)S_ROUND(offset, shdr->sh_addralign); 257 offset += shdr->sh_size; 258 259 /* 260 * If this is a NOBITS output section convert all of 261 * its associated input sections into real, null filled, 262 * data buffers, and change the section to PROGBITS. 263 */ 264 if (shdr->sh_type == SHT_NOBITS) 265 shdr->sh_type = SHT_PROGBITS; 266 } 267 268 /* 269 * If this is a loadable segment retain the last output section 270 * descriptor. This acts both as a flag that a loadable 271 * segment has been seen, and as the segment to which a padding 272 * buffer will be added. 273 */ 274 if (phdr->p_type == PT_LOAD) 275 oscn = osp->os_scn; 276 } 277 return (1); 278 } 279 280 /* 281 * Create an output section. The first instance of an input section triggers 282 * the creation of a new output section. 283 */ 284 static uintptr_t 285 create_outsec(Ofl_desc *ofl, Sg_desc *sgp, Os_desc *osp, Word ptype, int shidx, 286 Boolean fixalign) 287 { 288 Elf_Scn *scn; 289 Shdr *shdr; 290 291 /* 292 * Get a section descriptor for the section. 293 */ 294 if ((scn = elf_newscn(ofl->ofl_welf)) == NULL) { 295 eprintf(ofl->ofl_lml, ERR_ELF, MSG_INTL(MSG_ELF_NEWSCN), 296 ofl->ofl_name); 297 return (S_ERROR); 298 } 299 osp->os_scn = scn; 300 301 /* 302 * Get a new section header table entry and copy the pertinent 303 * information from the in-core descriptor. 304 */ 305 if ((shdr = elf_getshdr(scn)) == NULL) { 306 eprintf(ofl->ofl_lml, ERR_ELF, MSG_INTL(MSG_ELF_GETSHDR), 307 ofl->ofl_name); 308 return (S_ERROR); 309 } 310 *shdr = *(osp->os_shdr); 311 osp->os_shdr = shdr; 312 313 /* 314 * If this is the first section within a loadable segment, and the 315 * alignment needs to be updated, record this section. 316 */ 317 if ((fixalign == TRUE) && (ptype == PT_LOAD) && (shidx == 1)) 318 sgp->sg_fscn = scn; 319 320 /* 321 * If not building a relocatable object, remove any of the 322 * following flags, as they have been acted upon and are not 323 * meaningful in the output: 324 * SHF_ORDERED, SHF_LINK_ORDER, SHF_GROUP 325 * For relocatable objects, we allow them to propagate to 326 * the output object to be handled by the next linker that 327 * sees them. 328 */ 329 if ((ofl->ofl_flags & FLG_OF_RELOBJ) == 0) 330 osp->os_shdr->sh_flags &= ~(ALL_SHF_ORDER|SHF_GROUP); 331 332 /* 333 * If this is a TLS section, save it so that the PT_TLS program header 334 * information can be established after the output image has been 335 * initially created. At this point, all TLS input sections are ordered 336 * as they will appear in the output image. 337 */ 338 if ((ofl->ofl_flags & FLG_OF_TLSPHDR) && 339 (osp->os_shdr->sh_flags & SHF_TLS) && 340 (list_appendc(&ofl->ofl_ostlsseg, osp) == 0)) 341 return (S_ERROR); 342 343 return (0); 344 } 345 346 /* 347 * Recalculate the number of output sections and update ofl->ofl_shdrcnt. 348 * 349 * As new sections are placed, ofl->ofl_shdrcnt is incremented to 350 * track the count. If -z ignore is not in effect, then this is 351 * sufficient. If -z ignore is in effect however, the sections that 352 * are removed are not reflected in the value of ofl->ofl_shdrcnt. 353 * Determining whether ofl->ofl_shdrcnt should get decremented in 354 * that situation takes some work to determine, and if multiple 355 * sections are discarded (which is typical), then it would be 356 * necessary to do that work each time. Instead, we use this 357 * routine to recompute the number of output sections once at the end. 358 */ 359 void 360 ld_recalc_shdrcnt(Ofl_desc *ofl) 361 { 362 Sg_desc *sgp; 363 Listnode *lnp1, *lnp2; 364 Word cnt = 0; 365 Is_desc *isp; 366 Os_desc *osp; 367 Aliste idx; 368 369 370 /* 371 * This code must be kept in sync with the similar code 372 * found in ld_create_outfile(). 373 * 374 * We look at the input sections for every output section, 375 * looking for at least one input section that won't 376 * be eliminated. 377 */ 378 for (LIST_TRAVERSE(&ofl->ofl_segs, lnp1, sgp)) { 379 Word ptype = sgp->sg_phdr.p_type; 380 381 for (APLIST_TRAVERSE(sgp->sg_osdescs, idx, osp)) { 382 383 for (LIST_TRAVERSE(&(osp->os_isdescs), lnp2, isp)) { 384 Ifl_desc *ifl = isp->is_file; 385 386 /* Input section is tagged for discard? */ 387 if (isp->is_flags & FLG_IS_DISCARD) 388 continue; 389 390 /* 391 * If the file is discarded, it will take 392 * the section with it. 393 */ 394 if (ifl && 395 (((ifl->ifl_flags & FLG_IF_FILEREF) == 0) || 396 ((ptype == PT_LOAD) && 397 ((isp->is_flags & FLG_IS_SECTREF) == 0) && 398 (isp->is_shdr->sh_size > 0))) && 399 (ifl->ifl_flags & FLG_IF_IGNORE)) 400 continue; 401 402 /* 403 * We have found a kept input section. 404 * so the output section will be created. 405 */ 406 cnt++; 407 break; 408 } 409 } 410 } 411 ofl->ofl_shdrcnt = cnt; 412 } 413 414 /* 415 * Create the elf structures that allow the input data to be associated with the 416 * new image: 417 * 418 * o define the new elf image using elf_begin(), 419 * 420 * o obtain an elf header for the image, 421 * 422 * o traverse the input segments and create a program header array 423 * to define the required segments, 424 * 425 * o traverse the output sections for each segment assigning a new 426 * section descriptor and section header for each, 427 * 428 * o traverse the input sections associated with each output section 429 * and assign a new data descriptor to each (each output section 430 * becomes a linked list of input data buffers). 431 */ 432 uintptr_t 433 ld_create_outfile(Ofl_desc *ofl) 434 { 435 Listnode *lnp1; 436 Sg_desc *sgp; 437 Os_desc *osp; 438 Is_desc *isp; 439 Elf_Data *tlsdata = 0; 440 Aliste idx; 441 ofl_flag_t flags = ofl->ofl_flags; 442 ofl_flag_t flags1 = ofl->ofl_flags1; 443 size_t ndx = 0, fndx = 0; 444 Elf_Cmd cmd; 445 Boolean fixalign = FALSE; 446 int fd, nseg = 0, shidx = 0, dataidx = 0, ptloadidx = 0; 447 448 /* 449 * If DF_1_NOHDR was set in map_parse() or FLG_OF1_VADDR was set, 450 * we need to do alignment adjustment. 451 */ 452 if ((flags1 & FLG_OF1_VADDR) || 453 (ofl->ofl_dtflags_1 & DF_1_NOHDR)) { 454 fixalign = TRUE; 455 } 456 457 if (flags1 & FLG_OF1_MEMORY) { 458 cmd = ELF_C_IMAGE; 459 fd = 0; 460 } else { 461 fd = ofl->ofl_fd; 462 cmd = ELF_C_WRITE; 463 } 464 465 /* 466 * If there are any ordered sections, handle them here. 467 */ 468 if ((ofl->ofl_ordered.head != NULL) && 469 (ld_sort_ordered(ofl) == S_ERROR)) 470 return (S_ERROR); 471 472 /* 473 * Tell the access library about our new temporary file. 474 */ 475 if ((ofl->ofl_welf = elf_begin(fd, cmd, 0)) == NULL) { 476 eprintf(ofl->ofl_lml, ERR_ELF, MSG_INTL(MSG_ELF_BEGIN), 477 ofl->ofl_name); 478 return (S_ERROR); 479 } 480 481 /* 482 * Obtain a new Elf header. 483 */ 484 if ((ofl->ofl_nehdr = elf_newehdr(ofl->ofl_welf)) == NULL) { 485 eprintf(ofl->ofl_lml, ERR_ELF, MSG_INTL(MSG_ELF_NEWEHDR), 486 ofl->ofl_name); 487 return (S_ERROR); 488 } 489 ofl->ofl_nehdr->e_machine = ofl->ofl_dehdr->e_machine; 490 491 DBG_CALL(Dbg_util_nl(ofl->ofl_lml, DBG_NL_STD)); 492 for (LIST_TRAVERSE(&ofl->ofl_segs, lnp1, sgp)) { 493 int frst = 0; 494 Phdr *phdr = &(sgp->sg_phdr); 495 Word ptype = phdr->p_type; 496 497 /* 498 * Count the number of segments that will go in the program 499 * header table. If a segment is empty, ignore it. 500 */ 501 if (!(flags & FLG_OF_RELOBJ)) { 502 if (ptype == PT_PHDR) { 503 /* 504 * If we are generating an interp section (and 505 * thus an associated PT_INTERP program header 506 * entry) also generate a PT_PHDR program header 507 * entry. This allows the kernel to generate 508 * the appropriate aux vector entries to pass to 509 * the interpreter (refer to exec/elf/elf.c). 510 * Note that if an image was generated with an 511 * interp section, but no associated PT_PHDR 512 * program header entry, the kernel will simply 513 * pass the interpreter an open file descriptor 514 * when the image is executed). 515 */ 516 if (ofl->ofl_osinterp) 517 nseg++; 518 } else if (ptype == PT_INTERP) { 519 if (ofl->ofl_osinterp) 520 nseg++; 521 } else if (ptype == PT_DYNAMIC) { 522 if (flags & FLG_OF_DYNAMIC) 523 nseg++; 524 } else if (ptype == PT_TLS) { 525 if (flags & FLG_OF_TLSPHDR) 526 nseg++; 527 #if defined(_ELF64) 528 } else if ((ld_targ.t_m.m_mach == EM_AMD64) && 529 (ptype == PT_SUNW_UNWIND)) { 530 if (ofl->ofl_unwindhdr) 531 nseg++; 532 #endif 533 } else if (ptype == PT_SUNWDTRACE) { 534 if (ofl->ofl_dtracesym) 535 nseg++; 536 } else if (ptype == PT_SUNWCAP) { 537 if (ofl->ofl_oscap) 538 nseg++; 539 } else if (sgp->sg_flags & FLG_SG_EMPTY) { 540 nseg++; 541 } else if (sgp->sg_osdescs != NULL) { 542 if ((sgp->sg_flags & FLG_SG_PHREQ) == 0) { 543 /* 544 * If this is a segment for which 545 * we are not making a program header, 546 * don't increment nseg 547 */ 548 ptype = (sgp->sg_phdr).p_type = PT_NULL; 549 } else if (ptype != PT_NULL) 550 nseg++; 551 } 552 } 553 554 /* 555 * If the first loadable segment has the ?N flag, 556 * then ?N will be on. 557 */ 558 if ((ptype == PT_LOAD) && (ptloadidx == 0)) { 559 ptloadidx++; 560 if (sgp->sg_flags & FLG_SG_NOHDR) { 561 fixalign = TRUE; 562 ofl->ofl_dtflags_1 |= DF_1_NOHDR; 563 } 564 } 565 566 shidx = 0; 567 for (APLIST_TRAVERSE(sgp->sg_osdescs, idx, osp)) { 568 Listnode *lnp2; 569 570 dataidx = 0; 571 for (LIST_TRAVERSE(&(osp->os_isdescs), lnp2, isp)) { 572 Elf_Data * data; 573 Ifl_desc * ifl = isp->is_file; 574 575 /* 576 * An input section in the list that has 577 * been previously marked to be discarded 578 * should be completely ignored. 579 */ 580 if (isp->is_flags & FLG_IS_DISCARD) 581 continue; 582 583 /* 584 * At this point we know whether a section has 585 * been referenced. If it hasn't, and the whole 586 * file hasn't been referenced (which would have 587 * been caught in ignore_section_processing()), 588 * give a diagnostic (-D unused,detail) or 589 * discard the section if -zignore is in effect. 590 */ 591 if (ifl && 592 (((ifl->ifl_flags & FLG_IF_FILEREF) == 0) || 593 ((ptype == PT_LOAD) && 594 ((isp->is_flags & FLG_IS_SECTREF) == 0) && 595 (isp->is_shdr->sh_size > 0)))) { 596 Lm_list *lml = ofl->ofl_lml; 597 598 if (ifl->ifl_flags & FLG_IF_IGNORE) { 599 isp->is_flags |= FLG_IS_DISCARD; 600 DBG_CALL(Dbg_unused_sec(lml, 601 isp)); 602 continue; 603 } else { 604 DBG_CALL(Dbg_unused_sec(lml, 605 isp)); 606 } 607 } 608 609 /* 610 * If this section provides no data, and isn't 611 * referenced, then it can be discarded as well. 612 * Note, if this is the first input section 613 * associated to an output section, let it 614 * through, there may be a legitimate reason why 615 * the user wants a null section. Discarding 616 * additional sections is intended to remove the 617 * empty clutter the compilers have a habit of 618 * creating. Don't provide an unused diagnostic 619 * as these sections aren't typically the users 620 * creation. 621 */ 622 if (ifl && dataidx && 623 ((isp->is_flags & FLG_IS_SECTREF) == 0) && 624 (isp->is_shdr->sh_size == 0)) { 625 isp->is_flags |= FLG_IS_DISCARD; 626 continue; 627 } 628 629 /* 630 * The first input section triggers the creation 631 * of the associated output section. 632 */ 633 if (osp->os_scn == NULL) { 634 shidx++; 635 636 if (create_outsec(ofl, sgp, osp, ptype, 637 shidx, fixalign) == S_ERROR) 638 return (S_ERROR); 639 } 640 641 dataidx++; 642 643 /* 644 * Create a new output data buffer for each 645 * input data buffer, thus linking the new 646 * buffers to the new elf output structures. 647 * Simply make the new data buffers point to 648 * the old data. 649 */ 650 if ((data = elf_newdata(osp->os_scn)) == NULL) { 651 eprintf(ofl->ofl_lml, ERR_ELF, 652 MSG_INTL(MSG_ELF_NEWDATA), 653 ofl->ofl_name); 654 return (S_ERROR); 655 } 656 *data = *(isp->is_indata); 657 isp->is_indata = data; 658 659 if ((fixalign == TRUE) && (ptype == PT_LOAD) && 660 (shidx == 1) && (dataidx == 1)) 661 data->d_align = sgp->sg_addralign; 662 663 /* 664 * Save the first TLS data buffer, as this is 665 * the start of the TLS segment. Realign this 666 * buffer based on the alignment requirements 667 * of all the TLS input sections. 668 */ 669 if ((flags & FLG_OF_TLSPHDR) && 670 (isp->is_shdr->sh_flags & SHF_TLS)) { 671 if (tlsdata == 0) 672 tlsdata = data; 673 tlsdata->d_align = 674 ld_lcm(tlsdata->d_align, 675 isp->is_shdr->sh_addralign); 676 } 677 678 #if defined(_ELF64) && defined(_ILP32) 679 /* 680 * 4106312, the 32-bit ELF64 version of ld 681 * needs to be able to create large .bss 682 * sections. The d_size member of Elf_Data 683 * only allows 32-bits in _ILP32, so we build 684 * multiple data-items that each fit into 32- 685 * bits. libelf (4106398) can summ these up 686 * into a 64-bit quantity. This only works 687 * for NOBITS sections which don't have any 688 * real data to maintain and don't require 689 * large file support. 690 */ 691 if (isp->is_shdr->sh_type == SHT_NOBITS) { 692 Xword sz = isp->is_shdr->sh_size; 693 694 while (sz >> 32) { 695 data->d_size = SIZE_MAX; 696 sz -= (Xword)SIZE_MAX; 697 698 data = elf_newdata(osp->os_scn); 699 if (data == NULL) 700 return (S_ERROR); 701 } 702 data->d_size = (size_t)sz; 703 } 704 #endif 705 706 /* 707 * If this segment requires rounding realign the 708 * first data buffer associated with the first 709 * section. 710 */ 711 if ((frst++ == 0) && 712 (sgp->sg_flags & FLG_SG_ROUND)) { 713 Xword align; 714 715 if (data->d_align) 716 align = (Xword) 717 S_ROUND(data->d_align, 718 sgp->sg_round); 719 else 720 align = sgp->sg_round; 721 722 data->d_align = (size_t)align; 723 } 724 } 725 726 /* 727 * Clear the szoutrels counter so that it can be used 728 * again in the building of relocs. See machrel.c. 729 */ 730 osp->os_szoutrels = 0; 731 } 732 } 733 734 /* 735 * Build an empty PHDR. 736 */ 737 if (nseg) { 738 if ((ofl->ofl_phdr = elf_newphdr(ofl->ofl_welf, 739 nseg)) == NULL) { 740 eprintf(ofl->ofl_lml, ERR_ELF, 741 MSG_INTL(MSG_ELF_NEWPHDR), ofl->ofl_name); 742 return (S_ERROR); 743 } 744 } 745 746 /* 747 * If we need to generate a memory model, pad the image. 748 */ 749 if (flags1 & FLG_OF1_MEMORY) { 750 if (pad_outfile(ofl) == S_ERROR) 751 return (S_ERROR); 752 } 753 754 /* 755 * After all the basic input file processing, all data pointers are 756 * referencing two types of memory: 757 * 758 * o allocated memory, ie. elf structures, internal link 759 * editor structures, and any new sections that have been 760 * created. 761 * 762 * o original input file mmap'ed memory, ie. the actual data 763 * sections of the input file images. 764 * 765 * Up until now, the only memory modifications have been carried out on 766 * the allocated memory. Before carrying out any relocations, write the 767 * new output file image and reassign any necessary data pointers to the 768 * output files memory image. This insures that any relocation 769 * modifications are made to the output file image and not to the input 770 * file image, thus preventing the creation of dirty pages and reducing 771 * the overall swap space requirement. 772 * 773 * Write out the elf structure so as to create the new file image. 774 */ 775 if ((ofl->ofl_size = (size_t)elf_update(ofl->ofl_welf, 776 ELF_C_WRIMAGE)) == (size_t)-1) { 777 eprintf(ofl->ofl_lml, ERR_ELF, MSG_INTL(MSG_ELF_UPDATE), 778 ofl->ofl_name); 779 return (S_ERROR); 780 } 781 782 /* 783 * Initialize the true `ofl' information with the memory images address 784 * and size. This will be used to write() out the image once any 785 * relocation processing has been completed. We also use this image 786 * information to setup a new Elf descriptor, which is used to obtain 787 * all the necessary elf pointers within the new output image. 788 */ 789 if ((ofl->ofl_elf = elf_begin(0, ELF_C_IMAGE, 790 ofl->ofl_welf)) == NULL) { 791 eprintf(ofl->ofl_lml, ERR_ELF, MSG_INTL(MSG_ELF_BEGIN), 792 ofl->ofl_name); 793 return (S_ERROR); 794 } 795 if ((ofl->ofl_nehdr = elf_getehdr(ofl->ofl_elf)) == NULL) { 796 eprintf(ofl->ofl_lml, ERR_ELF, MSG_INTL(MSG_ELF_GETEHDR), 797 ofl->ofl_name); 798 return (S_ERROR); 799 } 800 if (!(flags & FLG_OF_RELOBJ)) 801 if ((ofl->ofl_phdr = elf_getphdr(ofl->ofl_elf)) == NULL) { 802 eprintf(ofl->ofl_lml, ERR_ELF, 803 MSG_INTL(MSG_ELF_GETPHDR), ofl->ofl_name); 804 return (S_ERROR); 805 } 806 807 /* 808 * Reinitialize the section descriptors, section headers and obtain new 809 * output data buffer pointers (these will be used to perform any 810 * relocations). 811 */ 812 for (LIST_TRAVERSE(&ofl->ofl_segs, lnp1, sgp)) { 813 Phdr *_phdr = &(sgp->sg_phdr); 814 Os_desc *osp; 815 Aliste idx; 816 Boolean recorded = FALSE; 817 818 for (APLIST_TRAVERSE(sgp->sg_osdescs, idx, osp)) { 819 /* 820 * Make sure that an output section was originally 821 * created. Input sections that had been marked as 822 * discarded may have made an output section 823 * unnecessary. Remove this alist entry so that 824 * future output section descriptor processing doesn't 825 * have to compensate for this empty section. 826 */ 827 if (osp->os_scn == NULL) { 828 aplist_delete(sgp->sg_osdescs, &idx); 829 continue; 830 } 831 832 if ((osp->os_scn = elf_getscn(ofl->ofl_elf, ++ndx)) == 833 NULL) { 834 eprintf(ofl->ofl_lml, ERR_ELF, 835 MSG_INTL(MSG_ELF_GETSCN), ofl->ofl_name, 836 ndx); 837 return (S_ERROR); 838 } 839 if ((osp->os_shdr = elf_getshdr(osp->os_scn)) == 840 NULL) { 841 eprintf(ofl->ofl_lml, ERR_ELF, 842 MSG_INTL(MSG_ELF_GETSHDR), ofl->ofl_name); 843 return (S_ERROR); 844 } 845 if ((fixalign == TRUE) && (sgp->sg_fscn != 0) && 846 (recorded == FALSE)) { 847 Elf_Scn *scn; 848 849 scn = sgp->sg_fscn; 850 if ((fndx = elf_ndxscn(scn)) == SHN_UNDEF) { 851 eprintf(ofl->ofl_lml, ERR_ELF, 852 MSG_INTL(MSG_ELF_NDXSCN), 853 ofl->ofl_name); 854 return (S_ERROR); 855 } 856 if (ndx == fndx) { 857 sgp->sg_fscn = osp->os_scn; 858 recorded = TRUE; 859 } 860 } 861 862 if ((osp->os_outdata = 863 elf_getdata(osp->os_scn, NULL)) == NULL) { 864 eprintf(ofl->ofl_lml, ERR_ELF, 865 MSG_INTL(MSG_ELF_GETDATA), ofl->ofl_name); 866 return (S_ERROR); 867 } 868 869 /* 870 * If this section is part of a loadable segment insure 871 * that the segments alignment is appropriate. 872 */ 873 if (_phdr->p_type == PT_LOAD) { 874 _phdr->p_align = ld_lcm(_phdr->p_align, 875 osp->os_shdr->sh_addralign); 876 } 877 } 878 } 879 return (1); 880 } 881