debugfs/set_fields.c

   1 /*
   2  * set_fields.c --- set a superblock value
   3  *
   4  * Copyright (C) 2000, 2001, 2002, 2003, 2004 by Theodore Ts'o.
   5  *
   6  * %Begin-Header%
   7  * This file may be redistributed under the terms of the GNU Public
   8  * License.
   9  * %End-Header%
  10  */
  11
  12 #define _XOPEN_SOURCE 600 /* for inclusion of strptime() and strtoull */
  13
  14 #ifdef HAVE_STRTOULL
  15 #define STRTOULL strtoull
  16 #else
  17 #define STRTOULL strtoul
  18 #endif
  19
  20 #include "config.h"
  21 #include <stdio.h>
  22 #include <unistd.h>
  23 #include <stdlib.h>
  24 #include <ctype.h>
  25 #include <string.h>
  26 #include <strings.h>
  27 #include <time.h>
  28 #include <sys/types.h>
  29 #include <sys/stat.h>
  30 #ifdef HAVE_ERRNO_H
  31 #include <errno.h>
  32 #endif
  33 #include <assert.h>
  34 #if HAVE_STRINGS_H
  35 #include <strings.h>
  36 #endif
  37 #include <fcntl.h>
  38 #include <utime.h>
  39
  40 #include "debugfs.h"
  41 #include "uuid/uuid.h"
  42 #include "e2p/e2p.h"
  43 #include "support/quotaio.h"
  44
  45 static struct ext2_super_block set_sb;
  46 static struct ext2_inode_large set_inode;
  47 static struct ext2_group_desc set_gd;
  48 static struct ext4_group_desc set_gd4;
  49 static struct mmp_struct set_mmp;
  50 static dgrp_t set_bg;
  51 static ext2_ino_t set_ino;
  52 static int array_idx;
  53
  54 #define FLAG_ARRAY      0x0001
  55 #define FLAG_ALIAS      0x0002  /* Data intersects with other field */
  56 #define FLAG_CSUM       0x0004
  57
  58 struct field_set_info {
  59         const char      *name;
  60         void    *ptr;
  61         void    *ptr2;
  62         unsigned int    size;
  63         errcode_t (*func)(struct field_set_info *info, char *field, char *arg);
  64         int flags;
  65         int max_idx;
  66 };
  67
  68 static errcode_t parse_uint(struct field_set_info *info, char *field, char *arg);
  69 static errcode_t parse_int(struct field_set_info *info, char *field, char *arg);
  70 static errcode_t parse_string(struct field_set_info *info, char *field, char *arg);
  71 static errcode_t parse_uuid(struct field_set_info *info, char *field, char *arg);
  72 static errcode_t parse_hashalg(struct field_set_info *info, char *field, char *arg);
  73 static errcode_t parse_encoding(struct field_set_info *info, char *field, char *arg);
  74 static errcode_t parse_time(struct field_set_info *info, char *field, char *arg);
  75 static errcode_t parse_bmap(struct field_set_info *info, char *field, char *arg);
  76 static errcode_t parse_gd_csum(struct field_set_info *info, char *field, char *arg);
  77 static errcode_t parse_inode_csum(struct field_set_info *info, char *field,
  78                                   char *arg);
  79 static errcode_t parse_mmp_clear(struct field_set_info *info, char *field,
  80                                  char *arg);
  81
  82 #if __GNUC_PREREQ (4, 6) || defined(__clang__)
  83 #pragma GCC diagnostic push
  84 #pragma GCC diagnostic ignored "-Wmissing-field-initializers"
  85 #endif
  86
  87 static struct field_set_info super_fields[] = {
  88         { "inodes_count", &set_sb.s_inodes_count, NULL, 4, parse_uint },
  89         { "blocks_count", &set_sb.s_blocks_count, &set_sb.s_blocks_count_hi,
  90                 4, parse_uint },
  91         { "r_blocks_count", &set_sb.s_r_blocks_count,
  92                 &set_sb.s_r_blocks_count_hi, 4, parse_uint },
  93         { "free_blocks_count", &set_sb.s_free_blocks_count,
  94                 &set_sb.s_free_blocks_hi, 4, parse_uint },
  95         { "free_inodes_count", &set_sb.s_free_inodes_count, NULL, 4, parse_uint },
  96         { "first_data_block", &set_sb.s_first_data_block, NULL, 4, parse_uint },
  97         { "log_block_size", &set_sb.s_log_block_size, NULL, 4, parse_uint },
  98         { "log_cluster_size", &set_sb.s_log_cluster_size, NULL, 4, parse_int },
  99         { "blocks_per_group", &set_sb.s_blocks_per_group, NULL, 4, parse_uint },
 100         { "clusters_per_group", &set_sb.s_clusters_per_group, NULL, 4, parse_uint },
 101         { "inodes_per_group", &set_sb.s_inodes_per_group, NULL, 4, parse_uint },
 102         { "mtime", &set_sb.s_mtime, NULL, 4, parse_time },
 103         { "wtime", &set_sb.s_wtime, NULL, 4, parse_time },
 104         { "mnt_count", &set_sb.s_mnt_count, NULL, 2, parse_uint },
 105         { "max_mnt_count", &set_sb.s_max_mnt_count, NULL, 2, parse_int },
 106         /* s_magic */
 107         { "state", &set_sb.s_state, NULL, 2, parse_uint },
 108         { "errors", &set_sb.s_errors, NULL, 2, parse_uint },
 109         { "minor_rev_level", &set_sb.s_minor_rev_level, NULL, 2, parse_uint },
 110         { "lastcheck", &set_sb.s_lastcheck, NULL, 4, parse_time },
 111         { "checkinterval", &set_sb.s_checkinterval, NULL, 4, parse_uint },
 112         { "creator_os", &set_sb.s_creator_os, NULL, 4, parse_uint },
 113         { "rev_level", &set_sb.s_rev_level, NULL, 4, parse_uint },
 114         { "def_resuid", &set_sb.s_def_resuid, NULL, 2, parse_uint },
 115         { "def_resgid", &set_sb.s_def_resgid, NULL, 2, parse_uint },
 116         { "first_ino", &set_sb.s_first_ino, NULL, 4, parse_uint },
 117         { "inode_size", &set_sb.s_inode_size, NULL, 2, parse_uint },
 118         { "block_group_nr", &set_sb.s_block_group_nr, NULL, 2, parse_uint },
 119         { "feature_compat", &set_sb.s_feature_compat, NULL, 4, parse_uint },
 120         { "feature_incompat", &set_sb.s_feature_incompat, NULL, 4, parse_uint },
 121         { "feature_ro_compat", &set_sb.s_feature_ro_compat, NULL, 4, parse_uint },
 122         { "uuid", &set_sb.s_uuid, NULL, 16, parse_uuid },
 123         { "volume_name",  &set_sb.s_volume_name, NULL, 16, parse_string },
 124         { "last_mounted",  &set_sb.s_last_mounted, NULL, 64, parse_string },
 125         { "algorithm_usage_bitmap", &set_sb.s_algorithm_usage_bitmap, NULL,
 126                   4, parse_uint },
 127         { "prealloc_blocks", &set_sb.s_prealloc_blocks, NULL, 1, parse_uint },
 128         { "prealloc_dir_blocks", &set_sb.s_prealloc_dir_blocks, NULL, 1,
 129                   parse_uint },
 130         { "reserved_gdt_blocks", &set_sb.s_reserved_gdt_blocks, NULL, 2,
 131                   parse_uint },
 132         { "journal_uuid", &set_sb.s_journal_uuid, NULL, 16, parse_uuid },
 133         { "journal_inum", &set_sb.s_journal_inum, NULL, 4, parse_uint },
 134         { "journal_dev", &set_sb.s_journal_dev, NULL, 4, parse_uint },
 135         { "last_orphan", &set_sb.s_last_orphan, NULL, 4, parse_uint },
 136         { "hash_seed", &set_sb.s_hash_seed, NULL, 16, parse_uuid },
 137         { "def_hash_version", &set_sb.s_def_hash_version, NULL, 1, parse_hashalg },
 138         { "jnl_backup_type", &set_sb.s_jnl_backup_type, NULL, 1, parse_uint },
 139         { "desc_size", &set_sb.s_desc_size, NULL, 2, parse_uint },
 140         { "default_mount_opts", &set_sb.s_default_mount_opts, NULL, 4, parse_uint },
 141         { "first_meta_bg", &set_sb.s_first_meta_bg, NULL, 4, parse_uint },
 142         { "mkfs_time", &set_sb.s_mkfs_time, NULL, 4, parse_time },
 143         { "jnl_blocks", &set_sb.s_jnl_blocks[0], NULL, 4, parse_uint, FLAG_ARRAY,
 144           17 },
 145         { "min_extra_isize", &set_sb.s_min_extra_isize, NULL, 2, parse_uint },
 146         { "want_extra_isize", &set_sb.s_want_extra_isize, NULL, 2, parse_uint },
 147         { "flags", &set_sb.s_flags, NULL, 4, parse_uint },
 148         { "raid_stride", &set_sb.s_raid_stride, NULL, 2, parse_uint },
 149         { "mmp_interval", &set_sb.s_mmp_update_interval, NULL, 2, parse_uint },
 150         { "mmp_block", &set_sb.s_mmp_block, NULL, 8, parse_uint },
 151         { "raid_stripe_width", &set_sb.s_raid_stripe_width, NULL, 4, parse_uint },
 152         { "log_groups_per_flex", &set_sb.s_log_groups_per_flex, NULL, 1, parse_uint },
 153         { "kbytes_written", &set_sb.s_kbytes_written, NULL, 8, parse_uint },
 154         { "snapshot_inum", &set_sb.s_snapshot_inum, NULL, 4, parse_uint },
 155         { "snapshot_id", &set_sb.s_snapshot_id, NULL, 4, parse_uint },
 156         { "snapshot_r_blocks_count", &set_sb.s_snapshot_r_blocks_count,
 157           NULL, 8, parse_uint },
 158         { "snapshot_list", &set_sb.s_snapshot_list, NULL, 4, parse_uint },
 159         { "mount_opts",  &set_sb.s_mount_opts, NULL, 64, parse_string },
 160         { "usr_quota_inum", &set_sb.s_usr_quota_inum, NULL, 4, parse_uint },
 161         { "grp_quota_inum", &set_sb.s_grp_quota_inum, NULL, 4, parse_uint },
 162         { "prj_quota_inum", &set_sb.s_prj_quota_inum, NULL, 4, parse_uint },
 163         { "overhead_blocks", &set_sb.s_overhead_blocks, NULL, 4, parse_uint },
 164         { "backup_bgs", &set_sb.s_backup_bgs[0], NULL, 4, parse_uint,
 165           FLAG_ARRAY, 2 },
 166         { "checksum", &set_sb.s_checksum, NULL, 4, parse_uint },
 167         { "checksum_type", &set_sb.s_checksum_type, NULL, 1, parse_uint },
 168         { "encryption_level", &set_sb.s_encryption_level, NULL, 1, parse_uint },
 169         { "error_count", &set_sb.s_error_count, NULL, 4, parse_uint },
 170         { "first_error_time", &set_sb.s_first_error_time, NULL, 4, parse_time },
 171         { "first_error_ino", &set_sb.s_first_error_ino, NULL, 4, parse_uint },
 172         { "first_error_block", &set_sb.s_first_error_block, NULL, 8, parse_uint },
 173         { "first_error_func", &set_sb.s_first_error_func, NULL, 32, parse_string },
 174         { "first_error_line", &set_sb.s_first_error_line, NULL, 4, parse_uint },
 175         { "last_error_time", &set_sb.s_last_error_time, NULL, 4, parse_time },
 176         { "last_error_ino", &set_sb.s_last_error_ino, NULL, 4, parse_uint },
 177         { "last_error_block", &set_sb.s_last_error_block, NULL, 8, parse_uint },
 178         { "last_error_func", &set_sb.s_last_error_func, NULL, 32, parse_string },
 179         { "last_error_line", &set_sb.s_last_error_line, NULL, 4, parse_uint },
 180         { "encrypt_algos", &set_sb.s_encrypt_algos, NULL, 1, parse_uint,
 181           FLAG_ARRAY, 4 },
 182         { "encrypt_pw_salt", &set_sb.s_encrypt_pw_salt, NULL, 16, parse_uuid },
 183         { "lpf_ino", &set_sb.s_lpf_ino, NULL, 4, parse_uint },
 184         { "checksum_seed", &set_sb.s_checksum_seed, NULL, 4, parse_uint },
 185         { "encoding", &set_sb.s_encoding, NULL, 2, parse_encoding },
 186         { 0, 0, 0, 0 }
 187 };
 188
 189 static struct field_set_info inode_fields[] = {
 190         { "mode", &set_inode.i_mode, NULL, 2, parse_uint },
 191         { "uid", &set_inode.i_uid, &set_inode.osd2.linux2.l_i_uid_high,
 192                 2, parse_uint },
 193         { "size", &set_inode.i_size, &set_inode.i_size_high, 4, parse_uint },
 194         { "atime", &set_inode.i_atime, &set_inode.i_atime_extra,
 195                 4, parse_time },
 196         { "ctime", &set_inode.i_ctime, &set_inode.i_ctime_extra,
 197                 4, parse_time },
 198         { "mtime", &set_inode.i_mtime, &set_inode.i_mtime_extra,
 199                 4, parse_time },
 200         { "dtime", &set_inode.i_dtime, NULL,
 201                 4, parse_time },
 202         { "gid", &set_inode.i_gid, &set_inode.osd2.linux2.l_i_gid_high,
 203                 2, parse_uint },
 204         { "links_count", &set_inode.i_links_count, NULL, 2, parse_uint },
 205         /* Special case: i_blocks is 4 bytes, i_blocks_high is 2 bytes */
 206         { "blocks", &set_inode.i_blocks, &set_inode.osd2.linux2.l_i_blocks_hi,
 207                 6, parse_uint },
 208         { "flags", &set_inode.i_flags, NULL, 4, parse_uint },
 209         { "version", &set_inode.osd1.linux1.l_i_version,
 210                 &set_inode.i_version_hi, 4, parse_uint },
 211         { "translator", &set_inode.osd1.hurd1.h_i_translator, NULL,
 212                 4, parse_uint, FLAG_ALIAS },
 213         { "block", &set_inode.i_block[0], NULL, 4, parse_uint, FLAG_ARRAY,
 214           EXT2_NDIR_BLOCKS },
 215         { "block[IND]", &set_inode.i_block[EXT2_IND_BLOCK], NULL, 4, parse_uint },
 216         { "block[DIND]", &set_inode.i_block[EXT2_DIND_BLOCK], NULL, 4, parse_uint },
 217         { "block[TIND]", &set_inode.i_block[EXT2_TIND_BLOCK], NULL, 4, parse_uint },
 218         { "generation", &set_inode.i_generation, NULL, 4, parse_uint },
 219         /* Special case: i_file_acl_high is 2 bytes */
 220         { "file_acl", &set_inode.i_file_acl,
 221                 &set_inode.osd2.linux2.l_i_file_acl_high, 6, parse_uint },
 222         { "faddr", &set_inode.i_faddr, NULL, 4, parse_uint },
 223         { "frag", &set_inode.osd2.hurd2.h_i_frag, NULL, 1, parse_uint, FLAG_ALIAS },
 224         { "fsize", &set_inode.osd2.hurd2.h_i_fsize, NULL, 1, parse_uint },
 225         { "checksum", &set_inode.osd2.linux2.l_i_checksum_lo,
 226                 &set_inode.i_checksum_hi, 2, parse_inode_csum, FLAG_CSUM },
 227         { "author", &set_inode.osd2.hurd2.h_i_author, NULL,
 228                 4, parse_uint, FLAG_ALIAS },
 229         { "extra_isize", &set_inode.i_extra_isize, NULL,
 230                 2, parse_uint },
 231         { "ctime_extra", &set_inode.i_ctime_extra, NULL,
 232                 4, parse_uint, FLAG_ALIAS },
 233         { "mtime_extra", &set_inode.i_mtime_extra, NULL,
 234                 4, parse_uint, FLAG_ALIAS  },
 235         { "atime_extra", &set_inode.i_atime_extra, NULL,
 236                 4, parse_uint, FLAG_ALIAS },
 237         { "crtime", &set_inode.i_crtime, &set_inode.i_crtime_extra,
 238                 4, parse_time },
 239         { "crtime_extra", &set_inode.i_crtime_extra, NULL,
 240                 4, parse_uint, FLAG_ALIAS },
 241         { "projid", &set_inode.i_projid, NULL, 4, parse_uint },
 242         { "bmap", NULL, NULL, 4, parse_bmap, FLAG_ARRAY },
 243         { 0, 0, 0, 0 }
 244 };
 245
 246 static struct field_set_info ext2_bg_fields[] = {
 247         { "block_bitmap", &set_gd.bg_block_bitmap, NULL, 4, parse_uint },
 248         { "inode_bitmap", &set_gd.bg_inode_bitmap, NULL, 4, parse_uint },
 249         { "inode_table", &set_gd.bg_inode_table, NULL, 4, parse_uint },
 250         { "free_blocks_count", &set_gd.bg_free_blocks_count, NULL, 2, parse_uint },
 251         { "free_inodes_count", &set_gd.bg_free_inodes_count, NULL, 2, parse_uint },
 252         { "used_dirs_count", &set_gd.bg_used_dirs_count, NULL, 2, parse_uint },
 253         { "flags", &set_gd.bg_flags, NULL, 2, parse_uint },
 254         { "itable_unused", &set_gd.bg_itable_unused, NULL, 2, parse_uint },
 255         { "checksum", &set_gd.bg_checksum, NULL, 2, parse_gd_csum },
 256         { 0, 0, 0, 0 }
 257 };
 258
 259 static struct field_set_info ext4_bg_fields[] = {
 260         { "block_bitmap", &set_gd4.bg_block_bitmap,
 261                 &set_gd4.bg_block_bitmap_hi, 4, parse_uint },
 262         { "inode_bitmap", &set_gd4.bg_inode_bitmap,
 263                 &set_gd4.bg_inode_bitmap_hi, 4, parse_uint },
 264         { "inode_table", &set_gd4.bg_inode_table,
 265                 &set_gd4.bg_inode_table_hi, 4, parse_uint },
 266         { "free_blocks_count", &set_gd4.bg_free_blocks_count,
 267                 &set_gd4.bg_free_blocks_count_hi, 2, parse_uint },
 268         { "free_inodes_count", &set_gd4.bg_free_inodes_count,
 269                 &set_gd4.bg_free_inodes_count_hi, 2, parse_uint },
 270         { "used_dirs_count", &set_gd4.bg_used_dirs_count,
 271                 &set_gd4.bg_used_dirs_count_hi, 2, parse_uint },
 272         { "flags", &set_gd4.bg_flags, NULL, 2, parse_uint },
 273         { "exclude_bitmap", &set_gd4.bg_exclude_bitmap_lo,
 274                 &set_gd4.bg_exclude_bitmap_hi, 4, parse_uint },
 275         { "block_bitmap_csum", &set_gd4.bg_block_bitmap_csum_lo,
 276                 &set_gd4.bg_block_bitmap_csum_hi, 2, parse_uint },
 277         { "inode_bitmap_csum", &set_gd4.bg_inode_bitmap_csum_lo,
 278                 &set_gd4.bg_inode_bitmap_csum_hi, 2, parse_uint },
 279         { "itable_unused", &set_gd4.bg_itable_unused,
 280                 &set_gd4.bg_itable_unused_hi, 2, parse_uint },
 281         { "checksum", &set_gd4.bg_checksum, NULL, 2, parse_gd_csum },
 282         { 0, 0, 0, 0 }
 283 };
 284
 285 static struct field_set_info mmp_fields[] = {
 286         { "clear", &set_mmp.mmp_magic, NULL, sizeof(set_mmp),
 287                 parse_mmp_clear, FLAG_ALIAS },
 288         { "magic", &set_mmp.mmp_magic, NULL, 4, parse_uint },
 289         { "seq", &set_mmp.mmp_seq, NULL, 4, parse_uint },
 290         { "time", &set_mmp.mmp_time, NULL, 8, parse_uint },
 291         { "nodename", &set_mmp.mmp_nodename, NULL, sizeof(set_mmp.mmp_nodename),
 292                 parse_string },
 293         { "bdevname", &set_mmp.mmp_bdevname, NULL, sizeof(set_mmp.mmp_bdevname),
 294                 parse_string },
 295         { "check_interval", &set_mmp.mmp_check_interval, NULL, 2, parse_uint },
 296         { "checksum", &set_mmp.mmp_checksum, NULL, 4, parse_uint },
 297         { 0, 0, 0, 0 }
 298 };
 299 #if __GNUC_PREREQ (4, 6)
 300 #pragma GCC diagnostic pop
 301 #endif
 302
 303 #ifdef UNITTEST
 304
 305
 306 static void do_verify_field_set_info(struct field_set_info *fields,
 307                 const void *data, size_t size)
 308 {
 309         struct field_set_info *ss, *ss2;
 310         const char *begin = (char *)data;
 311         const char *end = begin + size;
 312
 313         for (ss = fields ; ss->name ; ss++) {
 314                 const char *ptr;
 315
 316                 /* Check pointers */
 317                 ptr = ss->ptr;
 318                 assert(!ptr || (ptr >= begin && ptr < end));
 319                 ptr = ss->ptr2;
 320                 assert(!ptr || (ptr >= begin && ptr < end));
 321
 322                 /* Check function */
 323                 assert(ss->func);
 324
 325                 for (ss2 = fields ; ss2 != ss ; ss2++) {
 326                         /* Check duplicate names */
 327                         assert(strcmp(ss->name, ss2->name));
 328
 329                         if (ss->flags & FLAG_ALIAS || ss2->flags & FLAG_ALIAS)
 330                                 continue;
 331                         /* Check false aliases, might be copy-n-paste error */
 332                         assert(!ss->ptr || (ss->ptr != ss2->ptr &&
 333                                             ss->ptr != ss2->ptr2));
 334                         assert(!ss->ptr2 || (ss->ptr2 != ss2->ptr &&
 335                                              ss->ptr2 != ss2->ptr2));
 336                 }
 337         }
 338 }
 339
 340 int main(int argc, char **argv)
 341 {
 342         do_verify_field_set_info(super_fields, &set_sb, sizeof(set_sb));
 343         do_verify_field_set_info(inode_fields, &set_inode, sizeof(set_inode));
 344         do_verify_field_set_info(ext2_bg_fields, &set_gd, sizeof(set_gd));
 345         do_verify_field_set_info(ext4_bg_fields, &set_gd4, sizeof(set_gd4));
 346         do_verify_field_set_info(mmp_fields, &set_mmp, sizeof(set_mmp));
 347         return 0;
 348 }
 349
 350 ext2_filsys current_fs;
 351 ext2_ino_t root, cwd;
 352
 353 #endif /* UNITTEST */
 354
 355 static int check_suffix(const char *field)
 356 {
 357         int len = strlen(field);
 358
 359         if (len <= 3)
 360                 return 0;
 361         field += len-3;
 362         if (!strcmp(field, "_lo"))
 363                 return 1;
 364         if (!strcmp(field, "_hi"))
 365                 return 2;
 366         return 0;
 367 }
 368
 369 static struct field_set_info *find_field(struct field_set_info *fields,
 370                                          char *field)
 371 {
 372         struct field_set_info *ss;
 373         const char      *prefix;
 374         char            *arg, *delim, *idx, *tmp;
 375         int             suffix, prefix_len;
 376
 377         if (fields == super_fields)
 378                 prefix = "s_";
 379         else if (fields == inode_fields)
 380                 prefix = "i_";
 381         else
 382                 prefix = "bg_";
 383         prefix_len = strlen(prefix);
 384         if (strncmp(field, prefix, prefix_len) == 0)
 385                 field += prefix_len;
 386
 387         arg = malloc(strlen(field)+1);
 388         if (!arg)
 389                 return NULL;
 390         strcpy(arg, field);
 391
 392         idx = strchr(arg, '[');
 393         if (idx) {
 394                 *idx++ = 0;
 395                 delim = idx + strlen(idx) - 1;
 396                 if (!*idx || *delim != ']')
 397                         idx = 0;
 398                 else
 399                         *delim = 0;
 400         }
 401         /*
 402          * Can we parse the number?
 403          */
 404         if (idx) {
 405                 array_idx = strtol(idx, &tmp, 0);
 406                 if (*tmp) {
 407                         *(--idx) = '[';
 408                         *delim = ']';
 409                         idx = 0;
 410                 }
 411         }
 412
 413         /*
 414          * If there is a valid _hi or a _lo suffix, strip it off
 415          */
 416         suffix = check_suffix(arg);
 417         if (suffix > 0)
 418                 arg[strlen(arg)-3] = 0;
 419
 420         for (ss = fields ; ss->name ; ss++) {
 421                 if (suffix && ss->ptr2 == 0)
 422                         continue;
 423                 if (ss->flags & FLAG_ARRAY) {
 424                         if (!idx || (strcmp(ss->name, arg) != 0))
 425                                 continue;
 426                         if (ss->max_idx > 0 && array_idx >= ss->max_idx)
 427                                 continue;
 428                 } else {
 429                         if (strcmp(ss->name, arg) != 0)
 430                                 continue;
 431                 }
 432                 free(arg);
 433                 return ss;
 434         }
 435         free(arg);
 436         return NULL;
 437 }
 438
 439 /*
 440  * Note: info->size == 6 is special; this means a base size 4 bytes,
 441  * and secondary (high) size of 2 bytes.  This is needed for the
 442  * special case of i_blocks_high and i_file_acl_high.
 443  */
 444 static errcode_t parse_uint(struct field_set_info *info, char *field,
 445                             char *arg)
 446 {
 447         unsigned long long n, num, mask, limit;
 448         int suffix = check_suffix(field);
 449         char *tmp;
 450         void *field1 = info->ptr, *field2 = info->ptr2;
 451         int size = (info->size == 6) ? 4 : info->size;
 452         union {
 453                 __u64   *ptr64;
 454                 __u32   *ptr32;
 455                 __u16   *ptr16;
 456                 __u8    *ptr8;
 457         } u;
 458
 459         if (suffix == 1)
 460                 field2 = 0;
 461         if (suffix == 2) {
 462                 field1 = field2;
 463                 field2 = 0;
 464         }
 465
 466         u.ptr8 = (__u8 *) field1;
 467         if (info->flags & FLAG_ARRAY)
 468                 u.ptr8 += array_idx * info->size;
 469
 470         errno = 0;
 471         num = STRTOULL(arg, &tmp, 0);
 472         if (*tmp || errno) {
 473                 fprintf(stderr, "Couldn't parse '%s' for field %s.\n",
 474                         arg, info->name);
 475                 return EINVAL;
 476         }
 477         mask = ~0ULL >> ((8 - size) * 8);
 478         limit = ~0ULL >> ((8 - info->size) * 8);
 479         if (field2 && info->size != 6)
 480                 limit = ~0ULL >> ((8 - info->size*2) * 8);
 481
 482         if (num > limit) {
 483                 fprintf(stderr, "Value '%s' exceeds field %s maximum %llu.\n",
 484                         arg, info->name, limit);
 485                 return EINVAL;
 486         }
 487         n = num & mask;
 488         switch (size) {
 489         case 8:
 490                 /* Should never get here */
 491                 fprintf(stderr, "64-bit field %s has a second 64-bit field\n"
 492                         "defined; BUG?!?\n", info->name);
 493                 *u.ptr64 = 0;
 494                 break;
 495         case 4:
 496                 *u.ptr32 = n;
 497                 break;
 498         case 2:
 499                 *u.ptr16 = n;
 500                 break;
 501         case 1:
 502                 *u.ptr8 = n;
 503                 break;
 504         }
 505         if (!field2)
 506                 return 0;
 507         n = (size == 8) ? 0 : (num >> (size*8));
 508         u.ptr8 = (__u8 *) field2;
 509         if (info->size == 6)
 510                 size = 2;
 511         switch (size) {
 512         case 8:
 513                 *u.ptr64 = n;
 514                 break;
 515         case 4:
 516                 *u.ptr32 = n;
 517                 break;
 518         case 2:
 519                 *u.ptr16 = n;
 520                 break;
 521         case 1:
 522                 *u.ptr8 = n;
 523                 break;
 524         }
 525         return 0;
 526 }
 527
 528 static errcode_t parse_int(struct field_set_info *info,
 529                            char *field EXT2FS_ATTR((unused)), char *arg)
 530 {
 531         long    num;
 532         char *tmp;
 533         __s32   *ptr32;
 534         __s16   *ptr16;
 535         __s8    *ptr8;
 536
 537         num = strtol(arg, &tmp, 0);
 538         if (*tmp) {
 539                 fprintf(stderr, "Couldn't parse '%s' for field %s.\n",
 540                         arg, info->name);
 541                 return EINVAL;
 542         }
 543         switch (info->size) {
 544         case 4:
 545                 ptr32 = (__s32 *) info->ptr;
 546                 *ptr32 = num;
 547                 break;
 548         case 2:
 549                 ptr16 = (__s16 *) info->ptr;
 550                 *ptr16 = num;
 551                 break;
 552         case 1:
 553                 ptr8 = (__s8 *) info->ptr;
 554                 *ptr8 = num;
 555                 break;
 556         }
 557         return 0;
 558 }
 559
 560 static errcode_t parse_string(struct field_set_info *info,
 561                               char *field EXT2FS_ATTR((unused)), char *arg)
 562 {
 563         char    *cp = (char *) info->ptr;
 564
 565         if (strlen(arg) >= info->size) {
 566                 fprintf(stderr, "Error maximum size for %s is %d.\n",
 567                         info->name, info->size);
 568                 return EINVAL;
 569         }
 570         strcpy(cp, arg);
 571         return 0;
 572 }
 573
 574 static errcode_t parse_time(struct field_set_info *info,
 575                             char *field, char *arg)
 576 {
 577         __s64           t;
 578         __u32           t_low, t_high;
 579         __u32           *ptr_low, *ptr_high;
 580
 581         if (check_suffix(field))
 582                 return parse_uint(info, field, arg);
 583
 584         ptr_low  = (__u32 *) info->ptr;
 585         ptr_high = (__u32 *) info->ptr2;
 586
 587         t = string_to_time(arg);
 588
 589         if (t == -1) {
 590                 fprintf(stderr, "Couldn't parse '%s' for field %s.\n",
 591                         arg, info->name);
 592                 return EINVAL;
 593         }
 594         t_low = (__u32) t;
 595         t_high = ((t - (__s32)t) >> 32) & EXT4_EPOCH_MASK;
 596         *ptr_low = t_low;
 597         if (ptr_high)
 598                 *ptr_high = (*ptr_high & ~EXT4_EPOCH_MASK) | t_high;
 599         return 0;
 600 }
 601
 602 static errcode_t parse_uuid(struct field_set_info *info,
 603                             char *field EXT2FS_ATTR((unused)), char *arg)
 604 {
 605         unsigned char * p = (unsigned char *) info->ptr;
 606
 607         if ((strcasecmp(arg, "null") == 0) ||
 608             (strcasecmp(arg, "clear") == 0)) {
 609                 uuid_clear(p);
 610         } else if (strcasecmp(arg, "time") == 0) {
 611                 uuid_generate_time(p);
 612         } else if (strcasecmp(arg, "random") == 0) {
 613                 uuid_generate(p);
 614         } else if (uuid_parse(arg, p)) {
 615                 fprintf(stderr, "Invalid UUID format: %s\n", arg);
 616                 return EINVAL;
 617         }
 618         return 0;
 619 }
 620
 621 static errcode_t parse_hashalg(struct field_set_info *info,
 622                                char *field EXT2FS_ATTR((unused)), char *arg)
 623 {
 624         int     hashv;
 625         unsigned char   *p = (unsigned char *) info->ptr;
 626
 627         hashv = e2p_string2hash(arg);
 628         if (hashv < 0) {
 629                 fprintf(stderr, "Invalid hash algorithm: %s\n", arg);
 630                 return EINVAL;
 631         }
 632         *p = hashv;
 633         return 0;
 634 }
 635
 636 static errcode_t parse_encoding(struct field_set_info *info,
 637                                 char *field EXT2FS_ATTR((unused)), char *arg)
 638 {
 639         int     encoding;
 640         unsigned char   *p = (unsigned char *) info->ptr;
 641
 642         encoding = e2p_str2encoding(arg);
 643         if (encoding < 0)
 644                 return parse_uint(info, field, arg);
 645         *p = encoding;
 646         return 0;
 647 }
 648
 649 static errcode_t parse_bmap(struct field_set_info *info,
 650                             char *field EXT2FS_ATTR((unused)), char *arg)
 651 {
 652         blk64_t         blk;
 653         errcode_t       retval;
 654         char            *tmp;
 655
 656         blk = strtoull(arg, &tmp, 0);
 657         if (*tmp) {
 658                 fprintf(stderr, "Couldn't parse '%s' for field %s.\n",
 659                         arg, info->name);
 660                 return EINVAL;
 661         }
 662
 663         retval = ext2fs_bmap2(current_fs, set_ino,
 664                               (struct ext2_inode *) &set_inode,
 665                               NULL, BMAP_ALLOC | BMAP_SET, array_idx, NULL,
 666                               &blk);
 667         if (retval) {
 668                 com_err("set_inode", retval, "while setting block map");
 669         }
 670         return retval;
 671 }
 672
 673 static errcode_t parse_gd_csum(struct field_set_info *info, char *field,
 674                                char *arg)
 675 {
 676         __u16 *checksum = info->ptr;
 677
 678         if (strcmp(arg, "calc") == 0) {
 679                 *checksum = ext2fs_group_desc_csum(current_fs, set_bg);
 680                 printf("Checksum set to 0x%04x\n", *checksum);
 681                 return 0;
 682         }
 683         return parse_uint(info, field, arg);
 684 }
 685
 686 static errcode_t parse_inode_csum(struct field_set_info *info, char *field,
 687                                   char *arg)
 688 {
 689         errcode_t       retval = 0;
 690         __u32           crc;
 691         int             is_large_inode = 0;
 692
 693         if (strcmp(arg, "calc") == 0) {
 694                 size_t sz = EXT2_INODE_SIZE(current_fs->super);
 695                 struct ext2_inode_large *tmp_inode = NULL;
 696
 697                 retval = ext2fs_get_mem(sz, &tmp_inode);
 698                 if (retval)
 699                         goto out;
 700
 701                 retval = ext2fs_read_inode_full(current_fs, set_ino,
 702                                      (struct ext2_inode *) tmp_inode,
 703                                      sz);
 704                 if (retval)
 705                         goto out;
 706
 707 #ifdef WORDS_BIGENDIAN
 708                 ext2fs_swap_inode_full(current_fs, tmp_inode,
 709                                        tmp_inode, 1, sz);
 710 #endif
 711
 712                 if (sz > EXT2_GOOD_OLD_INODE_SIZE)
 713                         is_large_inode = 1;
 714
 715                 retval = ext2fs_inode_csum_set(current_fs, set_ino,
 716                                                tmp_inode);
 717                 if (retval)
 718                         goto out;
 719 #ifdef WORDS_BIGENDIAN
 720                 crc = set_inode.i_checksum_lo =
 721                         ext2fs_swab16(tmp_inode->i_checksum_lo);
 722
 723 #else
 724                 crc = set_inode.i_checksum_lo = tmp_inode->i_checksum_lo;
 725 #endif
 726                 if (is_large_inode &&
 727                     set_inode.i_extra_isize >=
 728                                 (offsetof(struct ext2_inode_large,
 729                                           i_checksum_hi) -
 730                                  EXT2_GOOD_OLD_INODE_SIZE)) {
 731 #ifdef WORDS_BIGENDIAN
 732                         set_inode.i_checksum_lo =
 733                                 ext2fs_swab16(tmp_inode->i_checksum_lo);
 734 #else
 735                         set_inode.i_checksum_hi = tmp_inode->i_checksum_hi;
 736 #endif
 737                         crc |= ((__u32)set_inode.i_checksum_hi) << 16;
 738                 }
 739                 printf("Checksum set to 0x%08x\n", crc);
 740         out:
 741                 ext2fs_free_mem(&tmp_inode);
 742                 return retval;
 743         }
 744         return parse_uint(info, field, arg);
 745 }
 746
 747 static void print_possible_fields(struct field_set_info *fields)
 748 {
 749         struct field_set_info *ss;
 750         const char      *type, *cmd;
 751         FILE *f;
 752         char name[40], idx[40];
 753
 754         if (fields == super_fields) {
 755                 type = "Superblock";
 756                 cmd = "set_super_value";
 757         } else if (fields == inode_fields) {
 758                 type = "Inode";
 759                 cmd = "set_inode";
 760         } else if (fields == mmp_fields) {
 761                 type = "MMP";
 762                 cmd = "set_mmp_value";
 763         } else {
 764                 type = "Block group descriptor";
 765                 cmd = "set_block_group";
 766         }
 767         f = open_pager();
 768
 769         fprintf(f, "%s fields supported by the %s command:\n", type, cmd);
 770
 771         for (ss = fields ; ss->name ; ss++) {
 772                 type = "unknown";
 773                 if (ss->func == parse_string)
 774                         type = "string";
 775                 else if (ss->func == parse_int)
 776                         type = "integer";
 777                 else if (ss->func == parse_uint)
 778                         type = "unsigned integer";
 779                 else if (ss->func == parse_uuid)
 780                         type = "UUID";
 781                 else if (ss->func == parse_hashalg)
 782                         type = "hash algorithm";
 783                 else if (ss->func == parse_time)
 784                         type = "date/time";
 785                 else if (ss->func == parse_bmap)
 786                         type = "set physical->logical block map";
 787                 else if (ss->func == parse_gd_csum)
 788                         type = "unsigned integer OR \"calc\"";
 789                 strcpy(name, ss->name);
 790                 if (ss->flags & FLAG_ARRAY) {
 791                         if (ss->max_idx > 0)
 792                                 sprintf(idx, "[%d]", ss->max_idx);
 793                         else
 794                                 strcpy(idx, "[]");
 795                         strcat(name, idx);
 796                 }
 797                 if (ss->ptr2)
 798                         strcat(name, "[_hi|_lo]");
 799                 fprintf(f, "\t%-25s\t%s\n", name, type);
 800         }
 801         close_pager(f);
 802 }
 803
 804
 805 void do_set_super(int argc, char *argv[], int sci_idx EXT2FS_ATTR((unused)),
 806                   void *infop EXT2FS_ATTR((unused)))
 807 {
 808         const char *usage = "<field> <value>\n"
 809                 "\t\"set_super_value -l\" will list the names of "
 810                 "superblock fields\n\twhich can be set.";
 811         static struct field_set_info *ss;
 812
 813         if ((argc == 2) && !strcmp(argv[1], "-l")) {
 814                 print_possible_fields(super_fields);
 815                 return;
 816         }
 817
 818         if (common_args_process(argc, argv, 3, 3, "set_super_value",
 819                                 usage, CHECK_FS_RW))
 820                 return;
 821
 822         if ((ss = find_field(super_fields, argv[1])) == 0) {
 823                 com_err(argv[0], 0, "invalid field specifier: %s", argv[1]);
 824                 return;
 825         }
 826         set_sb = *current_fs->super;
 827         if (ss->func(ss, argv[1], argv[2]) == 0) {
 828                 *current_fs->super = set_sb;
 829                 ext2fs_mark_super_dirty(current_fs);
 830         }
 831 }
 832
 833 void do_set_inode(int argc, char *argv[], int sci_idx EXT2FS_ATTR((unused)),
 834                   void *infop EXT2FS_ATTR((unused)))
 835 {
 836         const char *usage = "<inode> <field> <value>\n"
 837                 "\t\"set_inode_field -l\" will list the names of "
 838                 "the fields in an ext2 inode\n\twhich can be set.";
 839         static struct field_set_info *ss;
 840
 841         if ((argc == 2) && !strcmp(argv[1], "-l")) {
 842                 print_possible_fields(inode_fields);
 843                 return;
 844         }
 845
 846         if (common_args_process(argc, argv, 4, 4, "set_inode",
 847                                 usage, CHECK_FS_RW))
 848                 return;
 849
 850         if ((ss = find_field(inode_fields, argv[2])) == 0) {
 851                 com_err(argv[0], 0, "invalid field specifier: %s", argv[2]);
 852                 return;
 853         }
 854
 855         set_ino = string_to_inode(argv[1]);
 856         if (!set_ino)
 857                 return;
 858
 859         if (debugfs_read_inode2(set_ino,
 860                                 (struct ext2_inode *) &set_inode, argv[1],
 861                                 sizeof(set_inode),
 862                                 (ss->flags & FLAG_CSUM) ?
 863                                 READ_INODE_NOCSUM : 0))
 864                 return;
 865
 866         if (ss->func(ss, argv[2], argv[3]) == 0) {
 867                 debugfs_write_inode2(set_ino,
 868                                      (struct ext2_inode *) &set_inode,
 869                                      argv[1], sizeof(set_inode),
 870                                      (ss->flags & FLAG_CSUM) ?
 871                                      WRITE_INODE_NOCSUM : 0);
 872         }
 873 }
 874
 875 void do_set_block_group_descriptor(int argc, char *argv[],
 876                                    int sci_idx EXT2FS_ATTR((unused)),
 877                                    void *infop EXT2FS_ATTR((unused)))
 878 {
 879         const char *usage = "<bg number> <field> <value>\n"
 880                 "\t\"set_block_group -l\" will list the names of "
 881                 "the fields in a block group descriptor\n\twhich can be set.";
 882         struct field_set_info   *table;
 883         struct field_set_info   *ss;
 884         char                    *end;
 885         void                    *edit, *target;
 886         int                     size;
 887
 888         /*
 889          * Determine whether we are editing an ext2 or ext4 block group
 890          * descriptor.  Descriptors larger than ext4_group_desc cannot
 891          * have their fields edited yet, because they do not have any
 892          * names assigned.  When that happens, this function needs to
 893          * be updated for the new descriptor struct and fields.
 894          */
 895         if (current_fs &&
 896             EXT2_DESC_SIZE(current_fs->super) >= EXT2_MIN_DESC_SIZE_64BIT) {
 897                 table = ext4_bg_fields;
 898                 edit = &set_gd4;
 899                 size = sizeof(set_gd4);
 900         } else {
 901                 table = ext2_bg_fields;
 902                 edit = &set_gd;
 903                 size = sizeof(set_gd);
 904         }
 905
 906         if ((argc == 2) && !strcmp(argv[1], "-l")) {
 907                 print_possible_fields(table);
 908                 return;
 909         }
 910
 911         if (common_args_process(argc, argv, 4, 4, "set_block_group",
 912                                 usage, CHECK_FS_RW))
 913                 return;
 914
 915         set_bg = strtoul(argv[1], &end, 0);
 916         if (*end) {
 917                 com_err(argv[0], 0, "invalid block group number: %s", argv[1]);
 918                 return;
 919         }
 920
 921         if (set_bg >= current_fs->group_desc_count) {
 922                 com_err(argv[0], 0, "block group number too big: %d", set_bg);
 923                 return;
 924         }
 925
 926         if ((ss = find_field(table, argv[2])) == 0) {
 927                 com_err(argv[0], 0, "invalid field specifier: %s", argv[2]);
 928                 return;
 929         }
 930
 931         target = ext2fs_group_desc(current_fs, current_fs->group_desc, set_bg);
 932         memcpy(edit, target, size);
 933         if (ss->func(ss, argv[2], argv[3]) == 0) {
 934                 memcpy(target, edit, size);
 935                 ext2fs_mark_super_dirty(current_fs);
 936         }
 937 }
 938
 939 static errcode_t parse_mmp_clear(struct field_set_info *info,
 940                                  char *field EXT2FS_ATTR((unused)),
 941                                  char *arg EXT2FS_ATTR((unused)))
 942 {
 943         errcode_t retval;
 944
 945         retval = ext2fs_mmp_clear(current_fs);
 946         if (retval != 0)
 947                 com_err("set_mmp_value", retval, "while clearing MMP block\n");
 948         else
 949                 memcpy(info->ptr, current_fs->mmp_buf, info->size);
 950
 951         return 1; /* we don't need the MMP block written again */
 952 }
 953
 954 #ifdef CONFIG_MMP
 955 void do_set_mmp_value(int argc, char *argv[], int sci_idx EXT2FS_ATTR((unused)),
 956                       void *infop EXT2FS_ATTR((unused)))
 957 {
 958         const char *usage = "<field> <value>\n"
 959                 "\t\"set_mmp_value -l\" will list the names of "
 960                 "MMP fields\n\twhich can be set.";
 961         static struct field_set_info *smmp;
 962         struct mmp_struct *mmp_s;
 963         errcode_t retval;
 964
 965         if (argc == 2 && strcmp(argv[1], "-l") == 0) {
 966                 print_possible_fields(mmp_fields);
 967                 return;
 968         }
 969
 970         if (check_fs_open(argv[0]))
 971                 return;
 972
 973         if (current_fs->super->s_mmp_block == 0) {
 974                 com_err(argv[0], 0, "no MMP block allocated\n");
 975                 return;
 976         }
 977
 978         if (common_args_process(argc, argv, 2, 3, "set_mmp_value",
 979                                 usage, CHECK_FS_RW))
 980                 return;
 981
 982         mmp_s = current_fs->mmp_buf;
 983         if (mmp_s == NULL) {
 984                 retval = ext2fs_get_mem(current_fs->blocksize, &mmp_s);
 985                 if (retval) {
 986                         com_err(argv[0], retval, "allocating MMP buffer\n");
 987                         return;
 988                 }
 989                 retval = ext2fs_mmp_read(current_fs,
 990                                          current_fs->super->s_mmp_block, mmp_s);
 991                 if (retval) {
 992                         com_err(argv[0], retval, "reading MMP block %llu.\n",
 993                                 (long long)current_fs->super->s_mmp_block);
 994                         ext2fs_free_mem(&mmp_s);
 995                         return;
 996                 }
 997                 current_fs->mmp_buf = mmp_s;
 998         }
 999
1000         smmp = find_field(mmp_fields, argv[1]);
1001         if (smmp == 0) {
1002                 com_err(argv[0], 0, "invalid field specifier: %s", argv[1]);
1003                 return;
1004         }
1005
1006         set_mmp = *mmp_s;
1007         if (smmp->func(smmp, argv[1], argv[2]) == 0) {
1008                 ext2fs_mmp_write(current_fs, current_fs->super->s_mmp_block,
1009                                  &set_mmp);
1010                 *mmp_s = set_mmp;
1011         }
1012 }
1013 #else
1014 void do_set_mmp_value(int argc EXT2FS_ATTR((unused)),
1015                       char *argv[] EXT2FS_ATTR((unused)),
1016                       int sci_idx EXT2FS_ATTR((unused)),
1017                       void *infop EXT2FS_ATTR((unused)))
1018 {
1019         fprintf(stdout, "MMP is unsupported, please recompile with "
1020                         "--enable-mmp\n");
1021 }
1022 #endif
1023