tools/relocate-rela.c

   1 // SPDX-License-Identifier: GPL-2.0+ OR BSD-2-Clause
   2 /*
   3  * Copyright 2013 Freescale Semiconductor, Inc.
   4  *
   5  * 64-bit and little-endian target only until we need to support a different
   6  * arch that needs this.
   7  */
   8
   9 #include <elf.h>
  10 #include <errno.h>
  11 #include <inttypes.h>
  12 #include <stdarg.h>
  13 #include <stdbool.h>
  14 #include <stdio.h>
  15 #include <stdlib.h>
  16 #include <string.h>
  17 #include "compiler.h"
  18
  19 #ifndef EM_AARCH64
  20 #define EM_AARCH64              183
  21 #endif
  22
  23 #ifndef R_AARCH64_RELATIVE
  24 #define R_AARCH64_RELATIVE      1027
  25 #endif
  26
  27 #ifndef EM_MICROBLAZE
  28 #define EM_MICROBLAZE           189
  29 #endif
  30
  31 #ifndef R_MICROBLAZE_NONE
  32 #define R_MICROBLAZE_NONE       0
  33 #endif
  34
  35 #ifndef R_MICROBLAZE_32
  36 #define R_MICROBLAZE_32         1
  37 #endif
  38
  39 #ifndef R_MICROBLAZE_REL
  40 #define R_MICROBLAZE_REL        16
  41 #endif
  42
  43 #ifndef R_MICROBLAZE_GLOB_DAT
  44 #define R_MICROBLAZE_GLOB_DAT   18
  45 #endif
  46
  47 static int ei_class;
  48
  49 static uint64_t rela_start, rela_end, text_base, dyn_start;
  50
  51 static const bool debug_en;
  52
  53 static void debug(const char *fmt, ...)
  54 {
  55         va_list args;
  56
  57         if (debug_en) {
  58                 va_start(args, fmt);
  59                 vprintf(fmt, args);
  60                 va_end(args);
  61         }
  62 }
  63
  64 static bool supported_rela(Elf64_Rela *rela)
  65 {
  66         uint64_t mask = 0xffffffffULL; /* would be different on 32-bit */
  67         uint32_t type = rela->r_info & mask;
  68
  69         switch (type) {
  70         case R_AARCH64_RELATIVE:
  71                 return true;
  72         default:
  73                 fprintf(stderr, "warning: unsupported relocation type %"
  74                                 PRIu32 " at %" PRIx64 "\n",
  75                         type, rela->r_offset);
  76
  77                 return false;
  78         }
  79 }
  80
  81 static int decode_elf64(FILE *felf, char **argv)
  82 {
  83         size_t size;
  84         Elf64_Ehdr header;
  85         uint64_t section_header_base, section_header_size;
  86         uint64_t sh_addr, sh_offset, sh_size;
  87         Elf64_Half sh_index, sh_num;
  88         Elf64_Shdr *sh_table; /* Elf symbol table */
  89         int ret, i, machine;
  90         char *sh_str;
  91
  92         debug("64bit version\n");
  93
  94         /* Make sure we are at start */
  95         rewind(felf);
  96
  97         size = fread(&header, 1, sizeof(header), felf);
  98         if (size != sizeof(header)) {
  99                 fclose(felf);
 100                 return 25;
 101         }
 102
 103         machine = le16_to_cpu(header.e_machine);
 104         debug("Machine\t%d\n", machine);
 105
 106         if (machine != EM_AARCH64) {
 107                 fprintf(stderr, "%s: Not supported machine type\n", argv[0]);
 108                 return 30;
 109         }
 110
 111         text_base = le64_to_cpu(header.e_entry);
 112         section_header_base = le64_to_cpu(header.e_shoff);
 113         section_header_size = le16_to_cpu(header.e_shentsize) *
 114                               le16_to_cpu(header.e_shnum);
 115
 116         sh_table = malloc(section_header_size);
 117         if (!sh_table) {
 118                 fprintf(stderr, "%s: Cannot allocate space for section header\n",
 119                         argv[0]);
 120                 fclose(felf);
 121                 return 26;
 122         }
 123
 124         ret = fseek(felf, section_header_base, SEEK_SET);
 125         if (ret) {
 126                 fprintf(stderr, "%s: Can't set pointer to section header: %x/%lx\n",
 127                         argv[0], ret, section_header_base);
 128                 free(sh_table);
 129                 fclose(felf);
 130                 return 26;
 131         }
 132
 133         size = fread(sh_table, 1, section_header_size, felf);
 134         if (size != section_header_size) {
 135                 fprintf(stderr, "%s: Can't read section header: %lx/%lx\n",
 136                         argv[0], size, section_header_size);
 137                 free(sh_table);
 138                 fclose(felf);
 139                 return 27;
 140         }
 141
 142         sh_index = le16_to_cpu(header.e_shstrndx);
 143         sh_size = le64_to_cpu(sh_table[sh_index].sh_size);
 144         debug("e_shstrndx %x, sh_size %lx\n", sh_index, sh_size);
 145
 146         sh_str = malloc(sh_size);
 147         if (!sh_str) {
 148                 fprintf(stderr, "malloc failed\n");
 149                 free(sh_table);
 150                 fclose(felf);
 151                 return 28;
 152         }
 153
 154         /*
 155          * Specifies the byte offset from the beginning of the file
 156          * to the first byte in the section.
 157          */
 158         sh_offset = le64_to_cpu(sh_table[sh_index].sh_offset);
 159         sh_num = le16_to_cpu(header.e_shnum);
 160
 161         ret = fseek(felf, sh_offset, SEEK_SET);
 162         if (ret) {
 163                 fprintf(stderr, "Setting up sh_offset failed\n");
 164                 free(sh_str);
 165                 free(sh_table);
 166                 fclose(felf);
 167                 return 29;
 168         }
 169
 170         size = fread(sh_str, 1, sh_size, felf);
 171         if (size != sh_size) {
 172                 fprintf(stderr, "%s: Can't read section: %lx/%lx\n",
 173                         argv[0], size, sh_size);
 174                 free(sh_str);
 175                 free(sh_table);
 176                 fclose(felf);
 177                 return 30;
 178         }
 179
 180         for (i = 0; i < sh_num; i++) {
 181                 char *sh_name = sh_str + le32_to_cpu(sh_table[i].sh_name);
 182
 183                 debug("%s\n", sh_name);
 184
 185                 sh_addr = le64_to_cpu(sh_table[i].sh_addr);
 186                 sh_offset = le64_to_cpu(sh_table[i].sh_offset);
 187                 sh_size = le64_to_cpu(sh_table[i].sh_size);
 188
 189                 if (!strcmp(".rela.dyn", sh_name)) {
 190                         debug("Found section\t\".rela_dyn\"\n");
 191                         debug(" at addr\t0x%08x\n", sh_addr);
 192                         debug(" at offset\t0x%08x\n", sh_offset);
 193                         debug(" of size\t0x%08x\n", sh_size);
 194                         rela_start = sh_addr;
 195                         rela_end = rela_start + sh_size;
 196                         break;
 197                 }
 198         }
 199
 200         /* Clean up */
 201         free(sh_str);
 202         free(sh_table);
 203         fclose(felf);
 204
 205         debug("text_base\t0x%08lx\n", text_base);
 206         debug("rela_start\t0x%08lx\n", rela_start);
 207         debug("rela_end\t0x%08lx\n", rela_end);
 208
 209         if (!rela_start)
 210                 return 1;
 211
 212         return 0;
 213 }
 214
 215 static int decode_elf32(FILE *felf, char **argv)
 216 {
 217         size_t size;
 218         Elf32_Ehdr header;
 219         uint64_t section_header_base, section_header_size;
 220         uint32_t sh_addr, sh_offset, sh_size;
 221         Elf32_Half sh_index, sh_num;
 222         Elf32_Shdr *sh_table; /* Elf symbol table */
 223         int ret, i, machine;
 224         char *sh_str;
 225
 226         debug("32bit version\n");
 227
 228         /* Make sure we are at start */
 229         rewind(felf);
 230
 231         size = fread(&header, 1, sizeof(header), felf);
 232         if (size != sizeof(header)) {
 233                 fclose(felf);
 234                 return 25;
 235         }
 236
 237         machine = le16_to_cpu(header.e_machine);
 238         debug("Machine %d\n", machine);
 239
 240         if (machine != EM_MICROBLAZE) {
 241                 fprintf(stderr, "%s: Not supported machine type\n", argv[0]);
 242                 return 30;
 243         }
 244
 245         text_base = le32_to_cpu(header.e_entry);
 246         section_header_base = le32_to_cpu(header.e_shoff);
 247         section_header_size = le16_to_cpu(header.e_shentsize) *
 248                               le16_to_cpu(header.e_shnum);
 249
 250         sh_table = malloc(section_header_size);
 251         if (!sh_table) {
 252                 fprintf(stderr, "%s: Cannot allocate space for section header\n",
 253                         argv[0]);
 254                 fclose(felf);
 255                 return 26;
 256         }
 257
 258         ret = fseek(felf, section_header_base, SEEK_SET);
 259         if (ret) {
 260                 fprintf(stderr, "%s: Can't set pointer to section header: %x/%lx\n",
 261                         argv[0], ret, section_header_base);
 262                 free(sh_table);
 263                 fclose(felf);
 264                 return 26;
 265         }
 266
 267         size = fread(sh_table, 1, section_header_size, felf);
 268         if (size != section_header_size) {
 269                 fprintf(stderr, "%s: Can't read section header: %lx/%lx\n",
 270                         argv[0], size, section_header_size);
 271                 free(sh_table);
 272                 fclose(felf);
 273                 return 27;
 274         }
 275
 276         sh_index = le16_to_cpu(header.e_shstrndx);
 277         sh_size = le32_to_cpu(sh_table[sh_index].sh_size);
 278         debug("e_shstrndx %x, sh_size %lx\n", sh_index, sh_size);
 279
 280         sh_str = malloc(sh_size);
 281         if (!sh_str) {
 282                 fprintf(stderr, "malloc failed\n");
 283                 free(sh_table);
 284                 fclose(felf);
 285                 return 28;
 286         }
 287
 288         /*
 289          * Specifies the byte offset from the beginning of the file
 290          * to the first byte in the section.
 291          */
 292         sh_offset = le32_to_cpu(sh_table[sh_index].sh_offset);
 293         sh_num = le16_to_cpu(header.e_shnum);
 294
 295         ret = fseek(felf, sh_offset, SEEK_SET);
 296         if (ret) {
 297                 fprintf(stderr, "Setting up sh_offset failed\n");
 298                 free(sh_str);
 299                 free(sh_table);
 300                 fclose(felf);
 301                 return 29;
 302         }
 303
 304         size = fread(sh_str, 1, sh_size, felf);
 305         if (size != sh_size) {
 306                 fprintf(stderr, "%s: Can't read section: %lx/%x\n",
 307                         argv[0], size, sh_size);
 308                 free(sh_str);
 309                 free(sh_table);
 310                 fclose(felf);
 311                 return 30;
 312         }
 313
 314         for (i = 0; i < sh_num; i++) {
 315                 char *sh_name = sh_str + le32_to_cpu(sh_table[i].sh_name);
 316
 317                 debug("%s\n", sh_name);
 318
 319                 sh_addr = le64_to_cpu(sh_table[i].sh_addr);
 320                 sh_offset = le64_to_cpu(sh_table[i].sh_offset);
 321                 sh_size = le64_to_cpu(sh_table[i].sh_size);
 322
 323                 if (!strcmp(".rela.dyn", sh_name)) {
 324                         debug("Found section\t\".rela_dyn\"\n");
 325                         debug(" at addr\t0x%08x\n", sh_addr);
 326                         debug(" at offset\t0x%08x\n", sh_offset);
 327                         debug(" of size\t0x%08x\n", sh_size);
 328                         rela_start = sh_addr;
 329                         rela_end = rela_start + sh_size;
 330                 }
 331                 if (!strcmp(".dynsym", sh_name)) {
 332                         debug("Found section\t\".dynsym\"\n");
 333                         debug(" at addr\t0x%08x\n", sh_addr);
 334                         debug(" at offset\t0x%08x\n", sh_offset);
 335                         debug(" of size\t0x%08x\n", sh_size);
 336                         dyn_start = sh_addr;
 337                 }
 338         }
 339
 340         /* Clean up */
 341         free(sh_str);
 342         free(sh_table);
 343         fclose(felf);
 344
 345         debug("text_base\t0x%08lx\n", text_base);
 346         debug("rela_start\t0x%08lx\n", rela_start);
 347         debug("rela_end\t0x%08lx\n", rela_end);
 348         debug("dyn_start\t0x%08lx\n", dyn_start);
 349
 350         if (!rela_start)
 351                 return 1;
 352
 353         return 0;
 354 }
 355
 356 static int decode_elf(char **argv)
 357 {
 358         FILE *felf;
 359         size_t size;
 360         unsigned char e_ident[EI_NIDENT];
 361
 362         felf = fopen(argv[2], "r+b");
 363         if (!felf) {
 364                 fprintf(stderr, "%s: Cannot open %s: %s\n",
 365                         argv[0], argv[5], strerror(errno));
 366                 return 2;
 367         }
 368
 369         size = fread(e_ident, 1, EI_NIDENT, felf);
 370         if (size != EI_NIDENT) {
 371                 fclose(felf);
 372                 return 25;
 373         }
 374
 375         /* Check if this is really ELF file */
 376         if (e_ident[0] != 0x7f &&
 377             e_ident[1] != 'E' &&
 378             e_ident[2] != 'L' &&
 379             e_ident[3] != 'F') {
 380                 fclose(felf);
 381                 return 1;
 382         }
 383
 384         ei_class = e_ident[4];
 385         debug("EI_CLASS(1=32bit, 2=64bit) %d\n", ei_class);
 386
 387         if (ei_class == 2)
 388                 return decode_elf64(felf, argv);
 389
 390         return decode_elf32(felf, argv);
 391 }
 392
 393 static int rela_elf64(char **argv, FILE *f)
 394 {
 395         int i, num;
 396
 397         if ((rela_end - rela_start) % sizeof(Elf64_Rela)) {
 398                 fprintf(stderr, "%s: rela size isn't a multiple of Elf64_Rela\n", argv[0]);
 399                 return 3;
 400         }
 401
 402         num = (rela_end - rela_start) / sizeof(Elf64_Rela);
 403
 404         for (i = 0; i < num; i++) {
 405                 Elf64_Rela rela, swrela;
 406                 uint64_t pos = rela_start + sizeof(Elf64_Rela) * i;
 407                 uint64_t addr;
 408
 409                 if (fseek(f, pos, SEEK_SET) < 0) {
 410                         fprintf(stderr, "%s: %s: seek to %" PRIx64
 411                                         " failed: %s\n",
 412                                 argv[0], argv[1], pos, strerror(errno));
 413                 }
 414
 415                 if (fread(&rela, sizeof(rela), 1, f) != 1) {
 416                         fprintf(stderr, "%s: %s: read rela failed at %"
 417                                         PRIx64 "\n",
 418                                 argv[0], argv[1], pos);
 419                         return 4;
 420                 }
 421
 422                 swrela.r_offset = le64_to_cpu(rela.r_offset);
 423                 swrela.r_info = le64_to_cpu(rela.r_info);
 424                 swrela.r_addend = le64_to_cpu(rela.r_addend);
 425
 426                 if (!supported_rela(&swrela))
 427                         continue;
 428
 429                 debug("Rela %" PRIx64 " %" PRIu64 " %" PRIx64 "\n",
 430                       swrela.r_offset, swrela.r_info, swrela.r_addend);
 431
 432                 if (swrela.r_offset < text_base) {
 433                         fprintf(stderr, "%s: %s: bad rela at %" PRIx64 "\n",
 434                                 argv[0], argv[1], pos);
 435                         return 4;
 436                 }
 437
 438                 addr = swrela.r_offset - text_base;
 439
 440                 if (fseek(f, addr, SEEK_SET) < 0) {
 441                         fprintf(stderr, "%s: %s: seek to %"
 442                                         PRIx64 " failed: %s\n",
 443                                 argv[0], argv[1], addr, strerror(errno));
 444                 }
 445
 446                 if (fwrite(&rela.r_addend, sizeof(rela.r_addend), 1, f) != 1) {
 447                         fprintf(stderr, "%s: %s: write failed at %" PRIx64 "\n",
 448                                 argv[0], argv[1], addr);
 449                         return 4;
 450                 }
 451         }
 452
 453         return 0;
 454 }
 455
 456 static bool supported_rela32(Elf32_Rela *rela, uint32_t *type)
 457 {
 458         uint32_t mask = 0xffULL; /* would be different on 32-bit */
 459         *type = rela->r_info & mask;
 460
 461         debug("Type:\t");
 462
 463         switch (*type) {
 464         case R_MICROBLAZE_32:
 465                 debug("R_MICROBLAZE_32\n");
 466                 return true;
 467         case R_MICROBLAZE_GLOB_DAT:
 468                 debug("R_MICROBLAZE_GLOB_DAT\n");
 469                 return true;
 470         case R_MICROBLAZE_NONE:
 471                 debug("R_MICROBLAZE_NONE - ignoring - do nothing\n");
 472                 return false;
 473         case R_MICROBLAZE_REL:
 474                 debug("R_MICROBLAZE_REL\n");
 475                 return true;
 476         default:
 477                 fprintf(stderr, "warning: unsupported relocation type %"
 478                         PRIu32 " at %" PRIx32 "\n", *type, rela->r_offset);
 479
 480                 return false;
 481         }
 482 }
 483
 484 static int rela_elf32(char **argv, FILE *f)
 485 {
 486         int i, num, index;
 487         uint32_t value, type;
 488
 489         if ((rela_end - rela_start) % sizeof(Elf32_Rela)) {
 490                 fprintf(stderr, "%s: rela size isn't a multiple of Elf32_Rela\n", argv[0]);
 491                 return 3;
 492         }
 493
 494         num = (rela_end - rela_start) / sizeof(Elf32_Rela);
 495
 496         debug("Number of entries: %u\n", num);
 497
 498         for (i = 0; i < num; i++) {
 499                 Elf32_Rela rela, swrela;
 500                 Elf32_Sym symbols;
 501                 uint32_t pos = rela_start + sizeof(Elf32_Rela) * i;
 502                 uint32_t addr, pos_dyn;
 503
 504                 debug("\nPossition:\t%d/0x%x\n", i, pos);
 505
 506                 if (fseek(f, pos, SEEK_SET) < 0) {
 507                         fprintf(stderr, "%s: %s: seek to %" PRIx32
 508                                         " failed: %s\n",
 509                                 argv[0], argv[1], pos, strerror(errno));
 510                 }
 511
 512                 if (fread(&rela, sizeof(rela), 1, f) != 1) {
 513                         fprintf(stderr, "%s: %s: read rela failed at %"
 514                                         PRIx32 "\n",
 515                                 argv[0], argv[1], pos);
 516                         return 4;
 517                 }
 518
 519                 debug("Rela:\toffset:\t%" PRIx32 " r_info:\t%"
 520                       PRIu32 " r_addend:\t%" PRIx32 "\n",
 521                       rela.r_offset, rela.r_info, rela.r_addend);
 522
 523                 swrela.r_offset = le32_to_cpu(rela.r_offset);
 524                 swrela.r_info = le32_to_cpu(rela.r_info);
 525                 swrela.r_addend = le32_to_cpu(rela.r_addend);
 526
 527                 debug("SWRela:\toffset:\t%" PRIx32 " r_info:\t%"
 528                       PRIu32 " r_addend:\t%" PRIx32 "\n",
 529                       swrela.r_offset, swrela.r_info, swrela.r_addend);
 530
 531                 if (!supported_rela32(&swrela, &type))
 532                         continue;
 533
 534                 if (swrela.r_offset < text_base) {
 535                         fprintf(stderr, "%s: %s: bad rela at %" PRIx32 "\n",
 536                                 argv[0], argv[1], pos);
 537                         return 4;
 538                 }
 539
 540                 addr = swrela.r_offset - text_base;
 541
 542                 debug("Addr:\t0x%" PRIx32 "\n", addr);
 543
 544                 switch (type) {
 545                 case R_MICROBLAZE_REL:
 546                         if (fseek(f, addr, SEEK_SET) < 0) {
 547                                 fprintf(stderr, "%s: %s: seek to %"
 548                                         PRIx32 " failed: %s\n",
 549                                         argv[0], argv[1], addr, strerror(errno));
 550                                 return 5;
 551                         }
 552
 553                         debug("Write addend\n");
 554
 555                         if (fwrite(&rela.r_addend, sizeof(rela.r_addend), 1, f) != 1) {
 556                                 fprintf(stderr, "%s: %s: write failed at %" PRIx32 "\n",
 557                                         argv[0], argv[1], addr);
 558                                 return 4;
 559                         }
 560                         break;
 561                 case R_MICROBLAZE_32:
 562                 case R_MICROBLAZE_GLOB_DAT:
 563                         /* global symbols read it and add reloc offset */
 564                         index = swrela.r_info >> 8;
 565                         pos_dyn = dyn_start + sizeof(Elf32_Sym) * index;
 566
 567                         debug("Index:\t%d\n", index);
 568                         debug("Pos_dyn:\t0x%x\n", pos_dyn);
 569
 570                         if (fseek(f, pos_dyn, SEEK_SET) < 0) {
 571                                 fprintf(stderr, "%s: %s: seek to %"
 572                                         PRIx32 " failed: %s\n",
 573                                         argv[0], argv[1], pos_dyn, strerror(errno));
 574                                 return 5;
 575                         }
 576
 577                         if (fread(&symbols, sizeof(symbols), 1, f) != 1) {
 578                                 fprintf(stderr, "%s: %s: read symbols failed at %"
 579                                                 PRIx32 "\n",
 580                                         argv[0], argv[1], pos_dyn);
 581                                 return 4;
 582                         }
 583
 584                         debug("Symbol description:\n");
 585                         debug(" st_name:\t0x%x\n", symbols.st_name);
 586                         debug(" st_value:\t0x%x\n", symbols.st_value);
 587                         debug(" st_size:\t0x%x\n", symbols.st_size);
 588
 589                         value = swrela.r_addend + symbols.st_value;
 590
 591                         debug("Value:\t0x%x\n", value);
 592
 593                         if (fseek(f, addr, SEEK_SET) < 0) {
 594                                 fprintf(stderr, "%s: %s: seek to %"
 595                                         PRIx32 " failed: %s\n",
 596                                         argv[0], argv[1], addr, strerror(errno));
 597                                 return 5;
 598                         }
 599
 600                         if (fwrite(&value, sizeof(rela.r_addend), 1, f) != 1) {
 601                                 fprintf(stderr, "%s: %s: write failed at %" PRIx32 "\n",
 602                                         argv[0], argv[1], addr);
 603                                 return 4;
 604                         }
 605
 606                         break;
 607                 case R_MICROBLAZE_NONE:
 608                         debug("R_MICROBLAZE_NONE - skip\n");
 609                         break;
 610                 default:
 611                         fprintf(stderr, "warning: unsupported relocation type %"
 612                                 PRIu32 " at %" PRIx32 "\n",
 613                                 type, rela.r_offset);
 614                 }
 615         }
 616
 617         return 0;
 618 }
 619
 620 int main(int argc, char **argv)
 621 {
 622         FILE *f;
 623         int ret;
 624         uint64_t file_size;
 625
 626         if (argc != 3) {
 627                 fprintf(stderr, "Statically apply ELF rela relocations\n");
 628                 fprintf(stderr, "Usage: %s <bin file> <u-boot ELF>\n",
 629                         argv[0]);
 630                 return 1;
 631         }
 632
 633         ret = decode_elf(argv);
 634         if (ret) {
 635                 fprintf(stderr, "ELF decoding failed\n");
 636                 return ret;
 637         }
 638
 639         if (rela_start > rela_end || rela_start < text_base) {
 640                 fprintf(stderr, "%s: bad rela bounds\n", argv[0]);
 641                 return 3;
 642         }
 643
 644         rela_start -= text_base;
 645         rela_end -= text_base;
 646         dyn_start -= text_base;
 647
 648         f = fopen(argv[1], "r+b");
 649         if (!f) {
 650                 fprintf(stderr, "%s: Cannot open %s: %s\n",
 651                         argv[0], argv[1], strerror(errno));
 652                 return 2;
 653         }
 654
 655         fseek(f, 0, SEEK_END);
 656         file_size = ftell(f);
 657         rewind(f);
 658
 659         if (rela_end > file_size) {
 660                 // Most likely compiler inserted some section that didn't get
 661                 // objcopy-ed into the final binary
 662                 rela_end = file_size;
 663         }
 664
 665         if (ei_class == 2)
 666                 ret = rela_elf64(argv, f);
 667         else
 668                 ret = rela_elf32(argv, f);
 669
 670         if (fclose(f) < 0) {
 671                 fprintf(stderr, "%s: %s: close failed: %s\n",
 672                         argv[0], argv[1], strerror(errno));
 673                 return 4;
 674         }
 675
 676         return ret;
 677 }