usr/gen_init_cpio.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <sys/types.h>
   4 #include <sys/stat.h>
   5 #include <string.h>
   6 #include <unistd.h>
   7 #include <time.h>
   8 #include <fcntl.h>
   9 #include <errno.h>
  10 #include <ctype.h>
  11 #include <limits.h>
  12
  13 /*
  14  * Original work by Jeff Garzik
  15  *
  16  * External file lists, symlink, pipe and fifo support by Thayne Harbaugh
  17  */
  18
  19 #define xstr(s) #s
  20 #define str(s) xstr(s)
  21
  22 static unsigned int offset;
  23 static unsigned int ino = 721;
  24
  25 struct file_handler {
  26         const char *type;
  27         int (*handler)(const char *line);
  28 };
  29
  30 static void push_string(const char *name)
  31 {
  32         unsigned int name_len = strlen(name) + 1;
  33
  34         fputs(name, stdout);
  35         putchar(0);
  36         offset += name_len;
  37 }
  38
  39 static void push_pad (void)
  40 {
  41         while (offset & 3) {
  42                 putchar(0);
  43                 offset++;
  44         }
  45 }
  46
  47 static void push_rest(const char *name)
  48 {
  49         unsigned int name_len = strlen(name) + 1;
  50         unsigned int tmp_ofs;
  51
  52         fputs(name, stdout);
  53         putchar(0);
  54         offset += name_len;
  55
  56         tmp_ofs = name_len + 110;
  57         while (tmp_ofs & 3) {
  58                 putchar(0);
  59                 offset++;
  60                 tmp_ofs++;
  61         }
  62 }
  63
  64 static void push_hdr(const char *s)
  65 {
  66         fputs(s, stdout);
  67         offset += 110;
  68 }
  69
  70 static void cpio_trailer(void)
  71 {
  72         char s[256];
  73         const char name[] = "TRAILER!!!";
  74
  75         sprintf(s, "%s%08X%08X%08lX%08lX%08X%08lX"
  76                "%08X%08X%08X%08X%08X%08X%08X",
  77                 "070701",               /* magic */
  78                 0,                      /* ino */
  79                 0,                      /* mode */
  80                 (long) 0,               /* uid */
  81                 (long) 0,               /* gid */
  82                 1,                      /* nlink */
  83                 (long) 0,               /* mtime */
  84                 0,                      /* filesize */
  85                 0,                      /* major */
  86                 0,                      /* minor */
  87                 0,                      /* rmajor */
  88                 0,                      /* rminor */
  89                 (unsigned)strlen(name)+1, /* namesize */
  90                 0);                     /* chksum */
  91         push_hdr(s);
  92         push_rest(name);
  93
  94         while (offset % 512) {
  95                 putchar(0);
  96                 offset++;
  97         }
  98 }
  99
 100 static int cpio_mkslink(const char *name, const char *target,
 101                          unsigned int mode, uid_t uid, gid_t gid)
 102 {
 103         char s[256];
 104         time_t mtime = time(NULL);
 105
 106         sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX"
 107                "%08X%08X%08X%08X%08X%08X%08X",
 108                 "070701",               /* magic */
 109                 ino++,                  /* ino */
 110                 S_IFLNK | mode,         /* mode */
 111                 (long) uid,             /* uid */
 112                 (long) gid,             /* gid */
 113                 1,                      /* nlink */
 114                 (long) mtime,           /* mtime */
 115                 (unsigned)strlen(target)+1, /* filesize */
 116                 3,                      /* major */
 117                 1,                      /* minor */
 118                 0,                      /* rmajor */
 119                 0,                      /* rminor */
 120                 (unsigned)strlen(name) + 1,/* namesize */
 121                 0);                     /* chksum */
 122         push_hdr(s);
 123         push_string(name);
 124         push_pad();
 125         push_string(target);
 126         push_pad();
 127         return 0;
 128 }
 129
 130 static int cpio_mkslink_line(const char *line)
 131 {
 132         char name[PATH_MAX + 1];
 133         char target[PATH_MAX + 1];
 134         unsigned int mode;
 135         int uid;
 136         int gid;
 137         int rc = -1;
 138
 139         if (5 != sscanf(line, "%" str(PATH_MAX) "s %" str(PATH_MAX) "s %o %d %d", name, target, &mode, &uid, &gid)) {
 140                 fprintf(stderr, "Unrecognized dir format '%s'", line);
 141                 goto fail;
 142         }
 143         rc = cpio_mkslink(name, target, mode, uid, gid);
 144  fail:
 145         return rc;
 146 }
 147
 148 static int cpio_mkgeneric(const char *name, unsigned int mode,
 149                        uid_t uid, gid_t gid)
 150 {
 151         char s[256];
 152         time_t mtime = time(NULL);
 153
 154         sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX"
 155                "%08X%08X%08X%08X%08X%08X%08X",
 156                 "070701",               /* magic */
 157                 ino++,                  /* ino */
 158                 mode,                   /* mode */
 159                 (long) uid,             /* uid */
 160                 (long) gid,             /* gid */
 161                 2,                      /* nlink */
 162                 (long) mtime,           /* mtime */
 163                 0,                      /* filesize */
 164                 3,                      /* major */
 165                 1,                      /* minor */
 166                 0,                      /* rmajor */
 167                 0,                      /* rminor */
 168                 (unsigned)strlen(name) + 1,/* namesize */
 169                 0);                     /* chksum */
 170         push_hdr(s);
 171         push_rest(name);
 172         return 0;
 173 }
 174
 175 enum generic_types {
 176         GT_DIR,
 177         GT_PIPE,
 178         GT_SOCK
 179 };
 180
 181 struct generic_type {
 182         const char *type;
 183         mode_t mode;
 184 };
 185
 186 static struct generic_type generic_type_table[] = {
 187         [GT_DIR] = {
 188                 .type = "dir",
 189                 .mode = S_IFDIR
 190         },
 191         [GT_PIPE] = {
 192                 .type = "pipe",
 193                 .mode = S_IFIFO
 194         },
 195         [GT_SOCK] = {
 196                 .type = "sock",
 197                 .mode = S_IFSOCK
 198         }
 199 };
 200
 201 static int cpio_mkgeneric_line(const char *line, enum generic_types gt)
 202 {
 203         char name[PATH_MAX + 1];
 204         unsigned int mode;
 205         int uid;
 206         int gid;
 207         int rc = -1;
 208
 209         if (4 != sscanf(line, "%" str(PATH_MAX) "s %o %d %d", name, &mode, &uid, &gid)) {
 210                 fprintf(stderr, "Unrecognized %s format '%s'",
 211                         line, generic_type_table[gt].type);
 212                 goto fail;
 213         }
 214         mode |= generic_type_table[gt].mode;
 215         rc = cpio_mkgeneric(name, mode, uid, gid);
 216  fail:
 217         return rc;
 218 }
 219
 220 static int cpio_mkdir_line(const char *line)
 221 {
 222         return cpio_mkgeneric_line(line, GT_DIR);
 223 }
 224
 225 static int cpio_mkpipe_line(const char *line)
 226 {
 227         return cpio_mkgeneric_line(line, GT_PIPE);
 228 }
 229
 230 static int cpio_mksock_line(const char *line)
 231 {
 232         return cpio_mkgeneric_line(line, GT_SOCK);
 233 }
 234
 235 static int cpio_mknod(const char *name, unsigned int mode,
 236                        uid_t uid, gid_t gid, char dev_type,
 237                        unsigned int maj, unsigned int min)
 238 {
 239         char s[256];
 240         time_t mtime = time(NULL);
 241
 242         if (dev_type == 'b')
 243                 mode |= S_IFBLK;
 244         else
 245                 mode |= S_IFCHR;
 246
 247         sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX"
 248                "%08X%08X%08X%08X%08X%08X%08X",
 249                 "070701",               /* magic */
 250                 ino++,                  /* ino */
 251                 mode,                   /* mode */
 252                 (long) uid,             /* uid */
 253                 (long) gid,             /* gid */
 254                 1,                      /* nlink */
 255                 (long) mtime,           /* mtime */
 256                 0,                      /* filesize */
 257                 3,                      /* major */
 258                 1,                      /* minor */
 259                 maj,                    /* rmajor */
 260                 min,                    /* rminor */
 261                 (unsigned)strlen(name) + 1,/* namesize */
 262                 0);                     /* chksum */
 263         push_hdr(s);
 264         push_rest(name);
 265         return 0;
 266 }
 267
 268 static int cpio_mknod_line(const char *line)
 269 {
 270         char name[PATH_MAX + 1];
 271         unsigned int mode;
 272         int uid;
 273         int gid;
 274         char dev_type;
 275         unsigned int maj;
 276         unsigned int min;
 277         int rc = -1;
 278
 279         if (7 != sscanf(line, "%" str(PATH_MAX) "s %o %d %d %c %u %u",
 280                          name, &mode, &uid, &gid, &dev_type, &maj, &min)) {
 281                 fprintf(stderr, "Unrecognized nod format '%s'", line);
 282                 goto fail;
 283         }
 284         rc = cpio_mknod(name, mode, uid, gid, dev_type, maj, min);
 285  fail:
 286         return rc;
 287 }
 288
 289 /* Not marked static to keep the compiler quiet, as no one uses this yet... */
 290 static int cpio_mkfile(const char *name, const char *location,
 291                         unsigned int mode, uid_t uid, gid_t gid)
 292 {
 293         char s[256];
 294         char *filebuf = NULL;
 295         struct stat buf;
 296         int file = -1;
 297         int retval;
 298         int rc = -1;
 299
 300         mode |= S_IFREG;
 301
 302         retval = stat (location, &buf);
 303         if (retval) {
 304                 fprintf (stderr, "File %s could not be located\n", location);
 305                 goto error;
 306         }
 307
 308         file = open (location, O_RDONLY);
 309         if (file < 0) {
 310                 fprintf (stderr, "File %s could not be opened for reading\n", location);
 311                 goto error;
 312         }
 313
 314         filebuf = malloc(buf.st_size);
 315         if (!filebuf) {
 316                 fprintf (stderr, "out of memory\n");
 317                 goto error;
 318         }
 319
 320         retval = read (file, filebuf, buf.st_size);
 321         if (retval < 0) {
 322                 fprintf (stderr, "Can not read %s file\n", location);
 323                 goto error;
 324         }
 325
 326         sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX"
 327                "%08X%08X%08X%08X%08X%08X%08X",
 328                 "070701",               /* magic */
 329                 ino++,                  /* ino */
 330                 mode,                   /* mode */
 331                 (long) uid,             /* uid */
 332                 (long) gid,             /* gid */
 333                 1,                      /* nlink */
 334                 (long) buf.st_mtime,    /* mtime */
 335                 (int) buf.st_size,      /* filesize */
 336                 3,                      /* major */
 337                 1,                      /* minor */
 338                 0,                      /* rmajor */
 339                 0,                      /* rminor */
 340                 (unsigned)strlen(name) + 1,/* namesize */
 341                 0);                     /* chksum */
 342         push_hdr(s);
 343         push_string(name);
 344         push_pad();
 345
 346         fwrite(filebuf, buf.st_size, 1, stdout);
 347         offset += buf.st_size;
 348         push_pad();
 349         rc = 0;
 350
 351 error:
 352         if (filebuf) free(filebuf);
 353         if (file >= 0) close(file);
 354         return rc;
 355 }
 356
 357 static int cpio_mkfile_line(const char *line)
 358 {
 359         char name[PATH_MAX + 1];
 360         char location[PATH_MAX + 1];
 361         unsigned int mode;
 362         int uid;
 363         int gid;
 364         int rc = -1;
 365
 366         if (5 != sscanf(line, "%" str(PATH_MAX) "s %" str(PATH_MAX) "s %o %d %d", name, location, &mode, &uid, &gid)) {
 367                 fprintf(stderr, "Unrecognized file format '%s'", line);
 368                 goto fail;
 369         }
 370         rc = cpio_mkfile(name, location, mode, uid, gid);
 371  fail:
 372         return rc;
 373 }
 374
 375 void usage(const char *prog)
 376 {
 377         fprintf(stderr, "Usage:\n"
 378                 "\t%s <cpio_list>\n"
 379                 "\n"
 380                 "<cpio_list> is a file containing newline separated entries that\n"
 381                 "describe the files to be included in the initramfs archive:\n"
 382                 "\n"
 383                 "# a comment\n"
 384                 "file <name> <location> <mode> <uid> <gid>\n"
 385                 "dir <name> <mode> <uid> <gid>\n"
 386                 "nod <name> <mode> <uid> <gid> <dev_type> <maj> <min>\n"
 387                 "slink <name> <target> <mode> <uid> <gid>\n"
 388                 "pipe <name> <mode> <uid> <gid>\n"
 389                 "sock <name> <mode> <uid> <gid>\n"
 390                 "\n"
 391                 "<name>      name of the file/dir/nod/etc in the archive\n"
 392                 "<location>  location of the file in the current filesystem\n"
 393                 "<target>    link target\n"
 394                 "<mode>      mode/permissions of the file\n"
 395                 "<uid>       user id (0=root)\n"
 396                 "<gid>       group id (0=root)\n"
 397                 "<dev_type>  device type (b=block, c=character)\n"
 398                 "<maj>       major number of nod\n"
 399                 "<min>       minor number of nod\n"
 400                 "\n"
 401                 "example:\n"
 402                 "# A simple initramfs\n"
 403                 "dir /dev 0755 0 0\n"
 404                 "nod /dev/console 0600 0 0 c 5 1\n"
 405                 "dir /root 0700 0 0\n"
 406                 "dir /sbin 0755 0 0\n"
 407                 "file /sbin/kinit /usr/src/klibc/kinit/kinit 0755 0 0\n",
 408                 prog);
 409 }
 410
 411 struct file_handler file_handler_table[] = {
 412         {
 413                 .type    = "file",
 414                 .handler = cpio_mkfile_line,
 415         }, {
 416                 .type    = "nod",
 417                 .handler = cpio_mknod_line,
 418         }, {
 419                 .type    = "dir",
 420                 .handler = cpio_mkdir_line,
 421         }, {
 422                 .type    = "slink",
 423                 .handler = cpio_mkslink_line,
 424         }, {
 425                 .type    = "pipe",
 426                 .handler = cpio_mkpipe_line,
 427         }, {
 428                 .type    = "sock",
 429                 .handler = cpio_mksock_line,
 430         }, {
 431                 .type    = NULL,
 432                 .handler = NULL,
 433         }
 434 };
 435
 436 #define LINE_SIZE (2 * PATH_MAX + 50)
 437
 438 int main (int argc, char *argv[])
 439 {
 440         FILE *cpio_list;
 441         char line[LINE_SIZE];
 442         char *args, *type;
 443         int ec = 0;
 444         int line_nr = 0;
 445
 446         if (2 != argc) {
 447                 usage(argv[0]);
 448                 exit(1);
 449         }
 450
 451         if (! (cpio_list = fopen(argv[1], "r"))) {
 452                 fprintf(stderr, "ERROR: unable to open '%s': %s\n\n",
 453                         argv[1], strerror(errno));
 454                 usage(argv[0]);
 455                 exit(1);
 456         }
 457
 458         while (fgets(line, LINE_SIZE, cpio_list)) {
 459                 int type_idx;
 460                 size_t slen = strlen(line);
 461
 462                 line_nr++;
 463
 464                 if ('#' == *line) {
 465                         /* comment - skip to next line */
 466                         continue;
 467                 }
 468
 469                 if (! (type = strtok(line, " \t"))) {
 470                         fprintf(stderr,
 471                                 "ERROR: incorrect format, could not locate file type line %d: '%s'\n",
 472                                 line_nr, line);
 473                         ec = -1;
 474                         break;
 475                 }
 476
 477                 if ('\n' == *type) {
 478                         /* a blank line */
 479                         continue;
 480                 }
 481
 482                 if (slen == strlen(type)) {
 483                         /* must be an empty line */
 484                         continue;
 485                 }
 486
 487                 if (! (args = strtok(NULL, "\n"))) {
 488                         fprintf(stderr,
 489                                 "ERROR: incorrect format, newline required line %d: '%s'\n",
 490                                 line_nr, line);
 491                         ec = -1;
 492                 }
 493
 494                 for (type_idx = 0; file_handler_table[type_idx].type; type_idx++) {
 495                         int rc;
 496                         if (! strcmp(line, file_handler_table[type_idx].type)) {
 497                                 if ((rc = file_handler_table[type_idx].handler(args))) {
 498                                         ec = rc;
 499                                         fprintf(stderr, " line %d\n", line_nr);
 500                                 }
 501                                 break;
 502                         }
 503                 }
 504
 505                 if (NULL == file_handler_table[type_idx].type) {
 506                         fprintf(stderr, "unknown file type line %d: '%s'\n",
 507                                 line_nr, line);
 508                 }
 509         }
 510         if (ec == 0)
 511                 cpio_trailer();
 512
 513         exit(ec);
 514 }