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