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