1 // SPDX-License-Identifier: GPL-2.0 2 #include <stdio.h> 3 #include <stdlib.h> 4 #include <stdint.h> 5 #include <stdbool.h> 6 #include <sys/types.h> 7 #include <sys/stat.h> 8 #include <string.h> 9 #include <unistd.h> 10 #include <time.h> 11 #include <fcntl.h> 12 #include <errno.h> 13 #include <ctype.h> 14 #include <limits.h> 15 16 /* 17 * Original work by Jeff Garzik 18 * 19 * External file lists, symlink, pipe and fifo support by Thayne Harbaugh 20 * Hard link support by Luciano Rocha 21 */ 22 23 #define xstr(s) #s 24 #define str(s) xstr(s) 25 #define MIN(a, b) ((a) < (b) ? (a) : (b)) 26 27 static unsigned int offset; 28 static unsigned int ino = 721; 29 static time_t default_mtime; 30 static bool do_file_mtime; 31 static bool do_csum = false; 32 33 struct file_handler { 34 const char *type; 35 int (*handler)(const char *line); 36 }; 37 38 static void push_string(const char *name) 39 { 40 unsigned int name_len = strlen(name) + 1; 41 42 fputs(name, stdout); 43 putchar(0); 44 offset += name_len; 45 } 46 47 static void push_pad (void) 48 { 49 while (offset & 3) { 50 putchar(0); 51 offset++; 52 } 53 } 54 55 static void push_rest(const char *name) 56 { 57 unsigned int name_len = strlen(name) + 1; 58 unsigned int tmp_ofs; 59 60 fputs(name, stdout); 61 putchar(0); 62 offset += name_len; 63 64 tmp_ofs = name_len + 110; 65 while (tmp_ofs & 3) { 66 putchar(0); 67 offset++; 68 tmp_ofs++; 69 } 70 } 71 72 static void push_hdr(const char *s) 73 { 74 fputs(s, stdout); 75 offset += 110; 76 } 77 78 static void cpio_trailer(void) 79 { 80 char s[256]; 81 const char name[] = "TRAILER!!!"; 82 83 sprintf(s, "%s%08X%08X%08lX%08lX%08X%08lX" 84 "%08X%08X%08X%08X%08X%08X%08X", 85 do_csum ? "070702" : "070701", /* magic */ 86 0, /* ino */ 87 0, /* mode */ 88 (long) 0, /* uid */ 89 (long) 0, /* gid */ 90 1, /* nlink */ 91 (long) 0, /* mtime */ 92 0, /* filesize */ 93 0, /* major */ 94 0, /* minor */ 95 0, /* rmajor */ 96 0, /* rminor */ 97 (unsigned)strlen(name)+1, /* namesize */ 98 0); /* chksum */ 99 push_hdr(s); 100 push_rest(name); 101 102 while (offset % 512) { 103 putchar(0); 104 offset++; 105 } 106 } 107 108 static int cpio_mkslink(const char *name, const char *target, 109 unsigned int mode, uid_t uid, gid_t gid) 110 { 111 char s[256]; 112 113 if (name[0] == '/') 114 name++; 115 sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX" 116 "%08X%08X%08X%08X%08X%08X%08X", 117 do_csum ? "070702" : "070701", /* magic */ 118 ino++, /* ino */ 119 S_IFLNK | mode, /* mode */ 120 (long) uid, /* uid */ 121 (long) gid, /* gid */ 122 1, /* nlink */ 123 (long) default_mtime, /* mtime */ 124 (unsigned)strlen(target)+1, /* filesize */ 125 3, /* major */ 126 1, /* minor */ 127 0, /* rmajor */ 128 0, /* rminor */ 129 (unsigned)strlen(name) + 1,/* namesize */ 130 0); /* chksum */ 131 push_hdr(s); 132 push_string(name); 133 push_pad(); 134 push_string(target); 135 push_pad(); 136 return 0; 137 } 138 139 static int cpio_mkslink_line(const char *line) 140 { 141 char name[PATH_MAX + 1]; 142 char target[PATH_MAX + 1]; 143 unsigned int mode; 144 int uid; 145 int gid; 146 int rc = -1; 147 148 if (5 != sscanf(line, "%" str(PATH_MAX) "s %" str(PATH_MAX) "s %o %d %d", name, target, &mode, &uid, &gid)) { 149 fprintf(stderr, "Unrecognized dir format '%s'", line); 150 goto fail; 151 } 152 rc = cpio_mkslink(name, target, mode, uid, gid); 153 fail: 154 return rc; 155 } 156 157 static int cpio_mkgeneric(const char *name, unsigned int mode, 158 uid_t uid, gid_t gid) 159 { 160 char s[256]; 161 162 if (name[0] == '/') 163 name++; 164 sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX" 165 "%08X%08X%08X%08X%08X%08X%08X", 166 do_csum ? "070702" : "070701", /* magic */ 167 ino++, /* ino */ 168 mode, /* mode */ 169 (long) uid, /* uid */ 170 (long) gid, /* gid */ 171 2, /* nlink */ 172 (long) default_mtime, /* mtime */ 173 0, /* filesize */ 174 3, /* major */ 175 1, /* minor */ 176 0, /* rmajor */ 177 0, /* rminor */ 178 (unsigned)strlen(name) + 1,/* namesize */ 179 0); /* chksum */ 180 push_hdr(s); 181 push_rest(name); 182 return 0; 183 } 184 185 enum generic_types { 186 GT_DIR, 187 GT_PIPE, 188 GT_SOCK 189 }; 190 191 struct generic_type { 192 const char *type; 193 mode_t mode; 194 }; 195 196 static const struct generic_type generic_type_table[] = { 197 [GT_DIR] = { 198 .type = "dir", 199 .mode = S_IFDIR 200 }, 201 [GT_PIPE] = { 202 .type = "pipe", 203 .mode = S_IFIFO 204 }, 205 [GT_SOCK] = { 206 .type = "sock", 207 .mode = S_IFSOCK 208 } 209 }; 210 211 static int cpio_mkgeneric_line(const char *line, enum generic_types gt) 212 { 213 char name[PATH_MAX + 1]; 214 unsigned int mode; 215 int uid; 216 int gid; 217 int rc = -1; 218 219 if (4 != sscanf(line, "%" str(PATH_MAX) "s %o %d %d", name, &mode, &uid, &gid)) { 220 fprintf(stderr, "Unrecognized %s format '%s'", 221 line, generic_type_table[gt].type); 222 goto fail; 223 } 224 mode |= generic_type_table[gt].mode; 225 rc = cpio_mkgeneric(name, mode, uid, gid); 226 fail: 227 return rc; 228 } 229 230 static int cpio_mkdir_line(const char *line) 231 { 232 return cpio_mkgeneric_line(line, GT_DIR); 233 } 234 235 static int cpio_mkpipe_line(const char *line) 236 { 237 return cpio_mkgeneric_line(line, GT_PIPE); 238 } 239 240 static int cpio_mksock_line(const char *line) 241 { 242 return cpio_mkgeneric_line(line, GT_SOCK); 243 } 244 245 static int cpio_mknod(const char *name, unsigned int mode, 246 uid_t uid, gid_t gid, char dev_type, 247 unsigned int maj, unsigned int min) 248 { 249 char s[256]; 250 251 if (dev_type == 'b') 252 mode |= S_IFBLK; 253 else 254 mode |= S_IFCHR; 255 256 if (name[0] == '/') 257 name++; 258 sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX" 259 "%08X%08X%08X%08X%08X%08X%08X", 260 do_csum ? "070702" : "070701", /* magic */ 261 ino++, /* ino */ 262 mode, /* mode */ 263 (long) uid, /* uid */ 264 (long) gid, /* gid */ 265 1, /* nlink */ 266 (long) default_mtime, /* mtime */ 267 0, /* filesize */ 268 3, /* major */ 269 1, /* minor */ 270 maj, /* rmajor */ 271 min, /* rminor */ 272 (unsigned)strlen(name) + 1,/* namesize */ 273 0); /* chksum */ 274 push_hdr(s); 275 push_rest(name); 276 return 0; 277 } 278 279 static int cpio_mknod_line(const char *line) 280 { 281 char name[PATH_MAX + 1]; 282 unsigned int mode; 283 int uid; 284 int gid; 285 char dev_type; 286 unsigned int maj; 287 unsigned int min; 288 int rc = -1; 289 290 if (7 != sscanf(line, "%" str(PATH_MAX) "s %o %d %d %c %u %u", 291 name, &mode, &uid, &gid, &dev_type, &maj, &min)) { 292 fprintf(stderr, "Unrecognized nod format '%s'", line); 293 goto fail; 294 } 295 rc = cpio_mknod(name, mode, uid, gid, dev_type, maj, min); 296 fail: 297 return rc; 298 } 299 300 static int cpio_mkfile_csum(int fd, unsigned long size, uint32_t *csum) 301 { 302 while (size) { 303 unsigned char filebuf[65536]; 304 ssize_t this_read; 305 size_t i, this_size = MIN(size, sizeof(filebuf)); 306 307 this_read = read(fd, filebuf, this_size); 308 if (this_read <= 0 || this_read > this_size) 309 return -1; 310 311 for (i = 0; i < this_read; i++) 312 *csum += filebuf[i]; 313 314 size -= this_read; 315 } 316 /* seek back to the start for data segment I/O */ 317 if (lseek(fd, 0, SEEK_SET) < 0) 318 return -1; 319 320 return 0; 321 } 322 323 static int cpio_mkfile(const char *name, const char *location, 324 unsigned int mode, uid_t uid, gid_t gid, 325 unsigned int nlinks) 326 { 327 char s[256]; 328 struct stat buf; 329 unsigned long size; 330 int file; 331 int retval; 332 int rc = -1; 333 time_t mtime; 334 int namesize; 335 unsigned int i; 336 uint32_t csum = 0; 337 338 mode |= S_IFREG; 339 340 file = open (location, O_RDONLY); 341 if (file < 0) { 342 fprintf (stderr, "File %s could not be opened for reading\n", location); 343 goto error; 344 } 345 346 retval = fstat(file, &buf); 347 if (retval) { 348 fprintf(stderr, "File %s could not be stat()'ed\n", location); 349 goto error; 350 } 351 352 if (do_file_mtime) { 353 mtime = default_mtime; 354 } else { 355 mtime = buf.st_mtime; 356 if (mtime > 0xffffffff) { 357 fprintf(stderr, "%s: Timestamp exceeds maximum cpio timestamp, clipping.\n", 358 location); 359 mtime = 0xffffffff; 360 } 361 362 if (mtime < 0) { 363 fprintf(stderr, "%s: Timestamp negative, clipping.\n", 364 location); 365 mtime = 0; 366 } 367 } 368 369 if (buf.st_size > 0xffffffff) { 370 fprintf(stderr, "%s: Size exceeds maximum cpio file size\n", 371 location); 372 goto error; 373 } 374 375 if (do_csum && cpio_mkfile_csum(file, buf.st_size, &csum) < 0) { 376 fprintf(stderr, "Failed to checksum file %s\n", location); 377 goto error; 378 } 379 380 size = 0; 381 for (i = 1; i <= nlinks; i++) { 382 /* data goes on last link */ 383 if (i == nlinks) 384 size = buf.st_size; 385 386 if (name[0] == '/') 387 name++; 388 namesize = strlen(name) + 1; 389 sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX" 390 "%08lX%08X%08X%08X%08X%08X%08X", 391 do_csum ? "070702" : "070701", /* magic */ 392 ino, /* ino */ 393 mode, /* mode */ 394 (long) uid, /* uid */ 395 (long) gid, /* gid */ 396 nlinks, /* nlink */ 397 (long) mtime, /* mtime */ 398 size, /* filesize */ 399 3, /* major */ 400 1, /* minor */ 401 0, /* rmajor */ 402 0, /* rminor */ 403 namesize, /* namesize */ 404 size ? csum : 0); /* chksum */ 405 push_hdr(s); 406 push_string(name); 407 push_pad(); 408 409 while (size) { 410 unsigned char filebuf[65536]; 411 ssize_t this_read; 412 size_t this_size = MIN(size, sizeof(filebuf)); 413 414 this_read = read(file, filebuf, this_size); 415 if (this_read <= 0 || this_read > this_size) { 416 fprintf(stderr, "Can not read %s file\n", location); 417 goto error; 418 } 419 420 if (fwrite(filebuf, this_read, 1, stdout) != 1) { 421 fprintf(stderr, "writing filebuf failed\n"); 422 goto error; 423 } 424 offset += this_read; 425 size -= this_read; 426 } 427 push_pad(); 428 429 name += namesize; 430 } 431 ino++; 432 rc = 0; 433 434 error: 435 if (file >= 0) 436 close(file); 437 return rc; 438 } 439 440 static char *cpio_replace_env(char *new_location) 441 { 442 char expanded[PATH_MAX + 1]; 443 char *start, *end, *var; 444 445 while ((start = strstr(new_location, "${")) && 446 (end = strchr(start + 2, '}'))) { 447 *start = *end = 0; 448 var = getenv(start + 2); 449 snprintf(expanded, sizeof expanded, "%s%s%s", 450 new_location, var ? var : "", end + 1); 451 strcpy(new_location, expanded); 452 } 453 454 return new_location; 455 } 456 457 static int cpio_mkfile_line(const char *line) 458 { 459 char name[PATH_MAX + 1]; 460 char *dname = NULL; /* malloc'ed buffer for hard links */ 461 char location[PATH_MAX + 1]; 462 unsigned int mode; 463 int uid; 464 int gid; 465 int nlinks = 1; 466 int end = 0, dname_len = 0; 467 int rc = -1; 468 469 if (5 > sscanf(line, "%" str(PATH_MAX) "s %" str(PATH_MAX) 470 "s %o %d %d %n", 471 name, location, &mode, &uid, &gid, &end)) { 472 fprintf(stderr, "Unrecognized file format '%s'", line); 473 goto fail; 474 } 475 if (end && isgraph(line[end])) { 476 int len; 477 int nend; 478 479 dname = malloc(strlen(line)); 480 if (!dname) { 481 fprintf (stderr, "out of memory (%d)\n", dname_len); 482 goto fail; 483 } 484 485 dname_len = strlen(name) + 1; 486 memcpy(dname, name, dname_len); 487 488 do { 489 nend = 0; 490 if (sscanf(line + end, "%" str(PATH_MAX) "s %n", 491 name, &nend) < 1) 492 break; 493 len = strlen(name) + 1; 494 memcpy(dname + dname_len, name, len); 495 dname_len += len; 496 nlinks++; 497 end += nend; 498 } while (isgraph(line[end])); 499 } else { 500 dname = name; 501 } 502 rc = cpio_mkfile(dname, cpio_replace_env(location), 503 mode, uid, gid, nlinks); 504 fail: 505 if (dname_len) free(dname); 506 return rc; 507 } 508 509 static void usage(const char *prog) 510 { 511 fprintf(stderr, "Usage:\n" 512 "\t%s [-t <timestamp>] [-c] <cpio_list>\n" 513 "\n" 514 "<cpio_list> is a file containing newline separated entries that\n" 515 "describe the files to be included in the initramfs archive:\n" 516 "\n" 517 "# a comment\n" 518 "file <name> <location> <mode> <uid> <gid> [<hard links>]\n" 519 "dir <name> <mode> <uid> <gid>\n" 520 "nod <name> <mode> <uid> <gid> <dev_type> <maj> <min>\n" 521 "slink <name> <target> <mode> <uid> <gid>\n" 522 "pipe <name> <mode> <uid> <gid>\n" 523 "sock <name> <mode> <uid> <gid>\n" 524 "\n" 525 "<name> name of the file/dir/nod/etc in the archive\n" 526 "<location> location of the file in the current filesystem\n" 527 " expands shell variables quoted with ${}\n" 528 "<target> link target\n" 529 "<mode> mode/permissions of the file\n" 530 "<uid> user id (0=root)\n" 531 "<gid> group id (0=root)\n" 532 "<dev_type> device type (b=block, c=character)\n" 533 "<maj> major number of nod\n" 534 "<min> minor number of nod\n" 535 "<hard links> space separated list of other links to file\n" 536 "\n" 537 "example:\n" 538 "# A simple initramfs\n" 539 "dir /dev 0755 0 0\n" 540 "nod /dev/console 0600 0 0 c 5 1\n" 541 "dir /root 0700 0 0\n" 542 "dir /sbin 0755 0 0\n" 543 "file /sbin/kinit /usr/src/klibc/kinit/kinit 0755 0 0\n" 544 "\n" 545 "<timestamp> is time in seconds since Epoch that will be used\n" 546 "as mtime for symlinks, directories, regular and special files.\n" 547 "The default is to use the current time for all files, but\n" 548 "preserve modification time for regular files.\n" 549 "-c: calculate and store 32-bit checksums for file data.\n", 550 prog); 551 } 552 553 static const struct file_handler file_handler_table[] = { 554 { 555 .type = "file", 556 .handler = cpio_mkfile_line, 557 }, { 558 .type = "nod", 559 .handler = cpio_mknod_line, 560 }, { 561 .type = "dir", 562 .handler = cpio_mkdir_line, 563 }, { 564 .type = "slink", 565 .handler = cpio_mkslink_line, 566 }, { 567 .type = "pipe", 568 .handler = cpio_mkpipe_line, 569 }, { 570 .type = "sock", 571 .handler = cpio_mksock_line, 572 }, { 573 .type = NULL, 574 .handler = NULL, 575 } 576 }; 577 578 #define LINE_SIZE (2 * PATH_MAX + 50) 579 580 int main (int argc, char *argv[]) 581 { 582 FILE *cpio_list; 583 char line[LINE_SIZE]; 584 char *args, *type; 585 int ec = 0; 586 int line_nr = 0; 587 const char *filename; 588 589 default_mtime = time(NULL); 590 while (1) { 591 int opt = getopt(argc, argv, "t:ch"); 592 char *invalid; 593 594 if (opt == -1) 595 break; 596 switch (opt) { 597 case 't': 598 default_mtime = strtol(optarg, &invalid, 10); 599 if (!*optarg || *invalid) { 600 fprintf(stderr, "Invalid timestamp: %s\n", 601 optarg); 602 usage(argv[0]); 603 exit(1); 604 } 605 do_file_mtime = true; 606 break; 607 case 'c': 608 do_csum = true; 609 break; 610 case 'h': 611 case '?': 612 usage(argv[0]); 613 exit(opt == 'h' ? 0 : 1); 614 } 615 } 616 617 /* 618 * Timestamps after 2106-02-07 06:28:15 UTC have an ascii hex time_t 619 * representation that exceeds 8 chars and breaks the cpio header 620 * specification. Negative timestamps similarly exceed 8 chars. 621 */ 622 if (default_mtime > 0xffffffff || default_mtime < 0) { 623 fprintf(stderr, "ERROR: Timestamp out of range for cpio format\n"); 624 exit(1); 625 } 626 627 if (argc - optind != 1) { 628 usage(argv[0]); 629 exit(1); 630 } 631 filename = argv[optind]; 632 if (!strcmp(filename, "-")) 633 cpio_list = stdin; 634 else if (!(cpio_list = fopen(filename, "r"))) { 635 fprintf(stderr, "ERROR: unable to open '%s': %s\n\n", 636 filename, strerror(errno)); 637 usage(argv[0]); 638 exit(1); 639 } 640 641 while (fgets(line, LINE_SIZE, cpio_list)) { 642 int type_idx; 643 size_t slen = strlen(line); 644 645 line_nr++; 646 647 if ('#' == *line) { 648 /* comment - skip to next line */ 649 continue; 650 } 651 652 if (! (type = strtok(line, " \t"))) { 653 fprintf(stderr, 654 "ERROR: incorrect format, could not locate file type line %d: '%s'\n", 655 line_nr, line); 656 ec = -1; 657 break; 658 } 659 660 if ('\n' == *type) { 661 /* a blank line */ 662 continue; 663 } 664 665 if (slen == strlen(type)) { 666 /* must be an empty line */ 667 continue; 668 } 669 670 if (! (args = strtok(NULL, "\n"))) { 671 fprintf(stderr, 672 "ERROR: incorrect format, newline required line %d: '%s'\n", 673 line_nr, line); 674 ec = -1; 675 } 676 677 for (type_idx = 0; file_handler_table[type_idx].type; type_idx++) { 678 int rc; 679 if (! strcmp(line, file_handler_table[type_idx].type)) { 680 if ((rc = file_handler_table[type_idx].handler(args))) { 681 ec = rc; 682 fprintf(stderr, " line %d\n", line_nr); 683 } 684 break; 685 } 686 } 687 688 if (NULL == file_handler_table[type_idx].type) { 689 fprintf(stderr, "unknown file type line %d: '%s'\n", 690 line_nr, line); 691 } 692 } 693 if (ec == 0) 694 cpio_trailer(); 695 696 exit(ec); 697 } 698