debugfs/xattrs.c

   1 /*
   2  * xattrs.c --- Modify extended attributes via debugfs.
   3  *
   4  * Copyright (C) 2014 Oracle.  This file may be redistributed
   5  * under the terms of the GNU Public License.
   6  */
   7
   8 #include "config.h"
   9 #include <stdio.h>
  10 #ifdef HAVE_GETOPT_H
  11 #include <getopt.h>
  12 #else
  13 extern int optind;
  14 extern char *optarg;
  15 #endif
  16 #include <ctype.h>
  17 #include "support/cstring.h"
  18
  19 #include "debugfs.h"
  20
  21 #define PRINT_XATTR_HEX         0x01
  22 #define PRINT_XATTR_RAW         0x02
  23 #define PRINT_XATTR_C           0x04
  24 #define PRINT_XATTR_STATFMT     0x08
  25 #define PRINT_XATTR_NOQUOTES    0x10
  26
  27 /* Dump extended attributes */
  28 static void print_xattr_hex(FILE *f, const char *str, int len)
  29 {
  30         int i;
  31
  32         for (i = 0; i < len; i++)
  33                 fprintf(f, "%02x ", (unsigned char)str[i]);
  34 }
  35
  36 /* Dump extended attributes */
  37 static void print_xattr_string(FILE *f, const char *str, int len, int flags)
  38 {
  39         int printable = 0;
  40         int i;
  41
  42         if (flags & PRINT_XATTR_RAW) {
  43                 fwrite(str, len, 1, f);
  44                 return;
  45         }
  46
  47         if ((flags & PRINT_XATTR_C) == 0) {
  48                 /* check: is string "printable enough?" */
  49                 for (i = 0; i < len; i++)
  50                         if (isprint(str[i]))
  51                                 printable++;
  52
  53                 if (printable <= len*7/8)
  54                         flags |= PRINT_XATTR_HEX;
  55         }
  56
  57         if (flags & PRINT_XATTR_HEX) {
  58                 print_xattr_hex(f, str, len);
  59         } else {
  60                 if ((flags & PRINT_XATTR_NOQUOTES) == 0)
  61                         fputc('\"', f);
  62                 print_c_string(f, str, len);
  63                 if ((flags & PRINT_XATTR_NOQUOTES) == 0)
  64                         fputc('\"', f);
  65         }
  66 }
  67
  68 static void print_xattr(FILE *f, char *name, char *value, size_t value_len,
  69                         int print_flags)
  70 {
  71         print_xattr_string(f, name, strlen(name), PRINT_XATTR_NOQUOTES);
  72         fprintf(f, " (%zu)", value_len);
  73         if ((print_flags & PRINT_XATTR_STATFMT) &&
  74             (strcmp(name, "system.data") == 0))
  75                 value_len = 0;
  76         if (value_len != 0 &&
  77             (!(print_flags & PRINT_XATTR_STATFMT) || (value_len < 40))) {
  78                 fprintf(f, " = ");
  79                 print_xattr_string(f, value, value_len, print_flags);
  80         }
  81         fputc('\n', f);
  82 }
  83
  84 static int dump_attr(char *name, char *value, size_t value_len, void *data)
  85 {
  86         FILE *out = data;
  87
  88         fprintf(out, "  ");
  89         print_xattr(out, name, value, value_len, PRINT_XATTR_STATFMT);
  90         return 0;
  91 }
  92
  93 void dump_inode_attributes(FILE *out, ext2_ino_t ino)
  94 {
  95         struct ext2_xattr_handle *h;
  96         size_t sz;
  97         errcode_t err;
  98
  99         err = ext2fs_xattrs_open(current_fs, ino, &h);
 100         if (err)
 101                 return;
 102
 103         err = ext2fs_xattrs_read(h);
 104         if (err)
 105                 goto out;
 106
 107         err = ext2fs_xattrs_count(h, &sz);
 108         if (err || sz == 0)
 109                 goto out;
 110
 111         fprintf(out, "Extended attributes:\n");
 112         err = ext2fs_xattrs_iterate(h, dump_attr, out);
 113         if (err)
 114                 goto out;
 115
 116 out:
 117         err = ext2fs_xattrs_close(&h);
 118 }
 119
 120 void do_list_xattr(int argc, char **argv)
 121 {
 122         ext2_ino_t ino;
 123
 124         if (argc != 2) {
 125                 printf("%s: Usage: %s <file>\n", argv[0],
 126                        argv[0]);
 127                 return;
 128         }
 129
 130         if (check_fs_open(argv[0]))
 131                 return;
 132
 133         ino = string_to_inode(argv[1]);
 134         if (!ino)
 135                 return;
 136
 137         dump_inode_attributes(stdout, ino);
 138 }
 139
 140 void do_get_xattr(int argc, char **argv)
 141 {
 142         ext2_ino_t ino;
 143         struct ext2_xattr_handle *h;
 144         FILE *fp = NULL;
 145         char *buf = NULL;
 146         size_t buflen;
 147         int i;
 148         int print_flags = 0;
 149         unsigned int handle_flags = 0;
 150         errcode_t err;
 151
 152         reset_getopt();
 153         while ((i = getopt(argc, argv, "Cf:rxV")) != -1) {
 154                 switch (i) {
 155                 case 'f':
 156                         if (fp)
 157                                 fclose(fp);
 158                         fp = fopen(optarg, "w");
 159                         if (fp == NULL) {
 160                                 perror(optarg);
 161                                 return;
 162                         }
 163                         break;
 164                 case 'r':
 165                         handle_flags |= XATTR_HANDLE_FLAG_RAW;
 166                         break;
 167                 case 'x':
 168                         print_flags |= PRINT_XATTR_HEX;
 169                         break;
 170                 case 'V':
 171                         print_flags |= PRINT_XATTR_RAW|
 172                                 PRINT_XATTR_NOQUOTES;
 173                         break;
 174                 case 'C':
 175                         print_flags |= PRINT_XATTR_C;
 176                         break;
 177                 default:
 178                         goto usage;
 179                 }
 180         }
 181
 182         if (optind != argc - 2) {
 183         usage:
 184                 printf("%s: Usage: %s [-f outfile]|[-xVC] [-r] <file> <attr>\n",
 185                                argv[0], argv[0]);
 186
 187                 goto out2;
 188         }
 189
 190         if (check_fs_open(argv[0]))
 191                 goto out2;
 192
 193         ino = string_to_inode(argv[optind]);
 194         if (!ino)
 195                 goto out2;
 196
 197         err = ext2fs_xattrs_open(current_fs, ino, &h);
 198         if (err)
 199                 goto out2;
 200
 201         err = ext2fs_xattrs_flags(h, &handle_flags, NULL);
 202         if (err)
 203                 goto out;
 204
 205         err = ext2fs_xattrs_read(h);
 206         if (err)
 207                 goto out;
 208
 209         err = ext2fs_xattr_get(h, argv[optind + 1], (void **)&buf, &buflen);
 210         if (err)
 211                 goto out;
 212
 213         if (fp) {
 214                 fwrite(buf, buflen, 1, fp);
 215         } else {
 216                 if (print_flags & PRINT_XATTR_RAW) {
 217                         if (print_flags & (PRINT_XATTR_HEX|PRINT_XATTR_C))
 218                                 print_flags &= ~PRINT_XATTR_RAW;
 219                         print_xattr_string(stdout, buf, buflen, print_flags);
 220                 } else {
 221                         print_xattr(stdout, argv[optind + 1],
 222                                     buf, buflen, print_flags);
 223                 }
 224                 printf("\n");
 225         }
 226
 227         ext2fs_free_mem(&buf);
 228 out:
 229         ext2fs_xattrs_close(&h);
 230         if (err)
 231                 com_err(argv[0], err, "while getting extended attribute");
 232 out2:
 233         if (fp)
 234                 fclose(fp);
 235 }
 236
 237 void do_set_xattr(int argc, char **argv)
 238 {
 239         ext2_ino_t ino;
 240         struct ext2_xattr_handle *h;
 241         FILE *fp = NULL;
 242         char *buf = NULL;
 243         size_t buflen;
 244         unsigned int handle_flags = 0;
 245         int i;
 246         errcode_t err;
 247
 248         reset_getopt();
 249         while ((i = getopt(argc, argv, "f:r")) != -1) {
 250                 switch (i) {
 251                 case 'f':
 252                         if (fp)
 253                                 fclose(fp);
 254                         fp = fopen(optarg, "r");
 255                         if (fp == NULL) {
 256                                 perror(optarg);
 257                                 return;
 258                         }
 259                         break;
 260                 case 'r':
 261                         handle_flags |= XATTR_HANDLE_FLAG_RAW;
 262                         break;
 263                 default:
 264                         goto print_usage;
 265                 }
 266         }
 267
 268         if (!(fp && optind == argc - 2) && !(!fp && optind == argc - 3)) {
 269         print_usage:
 270                 printf("Usage:\t%s [-r] <file> <attr> <value>\n", argv[0]);
 271                 printf("\t%s -f <value_file> [-r] <file> <attr>\n", argv[0]);
 272                 goto out2;
 273         }
 274
 275         if (check_fs_open(argv[0]))
 276                 goto out2;
 277         if (check_fs_read_write(argv[0]))
 278                 goto out2;
 279         if (check_fs_bitmaps(argv[0]))
 280                 goto out2;
 281
 282         ino = string_to_inode(argv[optind]);
 283         if (!ino)
 284                 goto out2;
 285
 286         err = ext2fs_xattrs_open(current_fs, ino, &h);
 287         if (err)
 288                 goto out2;
 289
 290         err = ext2fs_xattrs_flags(h, &handle_flags, NULL);
 291         if (err)
 292                 goto out;
 293
 294         err = ext2fs_xattrs_read(h);
 295         if (err)
 296                 goto out;
 297
 298         if (fp) {
 299                 err = ext2fs_get_mem(current_fs->blocksize, &buf);
 300                 if (err)
 301                         goto out;
 302                 buflen = fread(buf, 1, current_fs->blocksize, fp);
 303         } else {
 304                 buf = argv[optind + 2];
 305                 buflen = parse_c_string(buf);
 306         }
 307
 308         err = ext2fs_xattr_set(h, argv[optind + 1], buf, buflen);
 309 out:
 310         ext2fs_xattrs_close(&h);
 311         if (err)
 312                 com_err(argv[0], err, "while setting extended attribute");
 313 out2:
 314         if (fp) {
 315                 fclose(fp);
 316                 ext2fs_free_mem(&buf);
 317         }
 318 }
 319
 320 void do_rm_xattr(int argc, char **argv)
 321 {
 322         ext2_ino_t ino;
 323         struct ext2_xattr_handle *h;
 324         int i;
 325         errcode_t err;
 326
 327         if (argc < 3) {
 328                 printf("%s: Usage: %s <file> <attrs>...\n", argv[0], argv[0]);
 329                 return;
 330         }
 331
 332         if (check_fs_open(argv[0]))
 333                 return;
 334         if (check_fs_read_write(argv[0]))
 335                 return;
 336         if (check_fs_bitmaps(argv[0]))
 337                 return;
 338
 339         ino = string_to_inode(argv[1]);
 340         if (!ino)
 341                 return;
 342
 343         err = ext2fs_xattrs_open(current_fs, ino, &h);
 344         if (err)
 345                 return;
 346
 347         err = ext2fs_xattrs_read(h);
 348         if (err)
 349                 goto out;
 350
 351         for (i = 2; i < argc; i++) {
 352                 err = ext2fs_xattr_remove(h, argv[i]);
 353                 if (err)
 354                         goto out;
 355         }
 356 out:
 357         ext2fs_xattrs_close(&h);
 358         if (err)
 359                 com_err(argv[0], err, "while removing extended attribute");
 360 }
 361
 362 /*
 363  * Return non-zero if the string has a minimal number of non-printable
 364  * characters.
 365  */
 366 static int is_mostly_printable(const char *cp, int len)
 367 {
 368         int     np = 0;
 369
 370         if (len < 0)
 371                 len = strlen(cp);
 372
 373         while (len--) {
 374                 if (!isprint(*cp++)) {
 375                         np++;
 376                         if (np > 3)
 377                                 return 0;
 378                 }
 379         }
 380         return 1;
 381 }
 382
 383 static void safe_print(FILE *f, const char *cp, int len)
 384 {
 385         unsigned char   ch;
 386
 387         if (len < 0)
 388                 len = strlen(cp);
 389
 390         while (len--) {
 391                 ch = *cp++;
 392                 if (ch > 128) {
 393                         fputs("M-", f);
 394                         ch -= 128;
 395                 }
 396                 if ((ch < 32) || (ch == 0x7f)) {
 397                         fputc('^', f);
 398                         ch ^= 0x40; /* ^@, ^A, ^B; ^? for DEL */
 399                 }
 400                 fputc(ch, f);
 401         }
 402 }
 403
 404 static void dump_xattr_raw_entries(FILE *f, unsigned char *buf,
 405                                    unsigned int start, unsigned int len,
 406                                    unsigned value_start)
 407 {
 408         struct ext2_ext_attr_entry ent;
 409         char *name;
 410         unsigned int off = start;
 411         unsigned int vstart;
 412
 413         while (off < len) {
 414                 if ((*(__u16 *) (buf + off)) == 0) {
 415                         fprintf(f, "last entry found at offset %u (%04o)\n",
 416                                 off, off);
 417                         break;
 418                 }
 419                 if ((off + sizeof(struct ext2_ext_attr_entry)) >= len) {
 420                 overrun:
 421                         fprintf(f, "xattr buffer overrun at %u (len = %u)\n",
 422                                 off, len);
 423                         break;
 424                 }
 425 #if WORDS_BIGENDIAN
 426                 ext2fs_swap_ext_attr_entry(&ent,
 427                         (struct ext2_ext_attr_entry *) (buf + off));
 428 #else
 429                 ent = *((struct ext2_ext_attr_entry *) (buf + off));
 430 #endif
 431                 fprintf(f, "offset = %d (%04o), name_len = %u, "
 432                         "name_index = %u\n",
 433                         off, off, ent.e_name_len, ent.e_name_index);
 434                 vstart = value_start + ent.e_value_offs;
 435                 fprintf(f, "value_offset = %d (%04o), value_inum = %u, "
 436                         "value_size = %u\n", ent.e_value_offs,
 437                         vstart, ent.e_value_inum, ent.e_value_size);
 438                 off += sizeof(struct ext2_ext_attr_entry);
 439                 fprintf(f, "name = ");
 440                 if ((off + ent.e_name_len) >= len)
 441                         fprintf(f, "<runs off end>");
 442                 else
 443                         safe_print(f, (char *)(buf + off), ent.e_name_len);
 444                 fputc('\n', f);
 445                 if (ent.e_value_size == 0)
 446                         goto skip_value;
 447                 fprintf(f, "value = ");
 448                 if (ent.e_value_inum)
 449                         fprintf(f, "<ino %u>", ent.e_value_inum);
 450                 else if (ent.e_value_offs >= len ||
 451                          (vstart + ent.e_value_size) > len)
 452                         fprintf(f, "<runs off end>");
 453                 if (is_mostly_printable((char *)(buf + vstart),
 454                                         ent.e_value_size))
 455                         safe_print(f, (char *)(buf + vstart),
 456                                    ent.e_value_size);
 457                 else {
 458                         fprintf(f, "<hexdump>\n");
 459                         do_byte_hexdump(f, (char *)(buf + vstart),
 460                                         ent.e_value_size);
 461                 }
 462                 fputc('\n', f);
 463         skip_value:
 464                 fputc('\n', f);
 465                 off += (ent.e_name_len + 3) & ~3;
 466         }
 467 }
 468
 469 void raw_inode_xattr_dump(FILE *f, unsigned char *buf, unsigned int len)
 470 {
 471         __u32 magic = ext2fs_le32_to_cpu(*((__le32 *) buf));
 472
 473         fprintf(f, "magic = %08x, length = %u, value_start =4 \n\n",
 474                 magic, len);
 475         if (magic == EXT2_EXT_ATTR_MAGIC)
 476                 dump_xattr_raw_entries(f, buf, 4, len, 4);
 477 }
 478
 479 void block_xattr_dump(FILE *f, unsigned char *buf, unsigned int len)
 480 {
 481         struct ext2_ext_attr_header header;
 482
 483 #ifdef WORDS_BIGENDIAN
 484         ext2fs_swap_ext_attr_header(&header,
 485                                     (struct ext2_ext_attr_header *) buf);
 486 #else
 487         header = *((struct ext2_ext_attr_header *) buf);
 488 #endif
 489         fprintf(f, "magic = %08x, length = %u\n", header.h_magic, len);
 490         if (header.h_magic != EXT2_EXT_ATTR_MAGIC)
 491                 return;
 492         fprintf(f, "refcount = %u, blocks = %u\n", header.h_refcount,
 493                 header.h_blocks);
 494         fprintf(f, "hash = %08x, checksum = %08x\n", header.h_hash,
 495                 header.h_checksum);
 496         fprintf(f, "reserved: %08x %08x %08x\n\n", header.h_reserved[0],
 497                 header.h_reserved[1], header.h_reserved[2]);
 498
 499         dump_xattr_raw_entries(f, buf,
 500                                sizeof(struct ext2_ext_attr_header), len, 0);
 501 }