1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16#include "ext4_utils.h"
17#include "make_ext4fs.h"
18#include "ext4_extents.h"
19#include "allocate.h"
20#include "ext4fixup.h"
21
22#include <sparse/sparse.h>
23
24#include <sys/types.h>
25#include <sys/stat.h>
26#include <sys/types.h>
27#include <fcntl.h>
28#include <unistd.h>
29
30#ifndef USE_MINGW
31#include <sys/mman.h>
32#endif
33
34#if defined(__APPLE__) && defined(__MACH__)
35#define lseek64 lseek
36#define off64_t off_t
37#endif
38
39/* The inode block count for a file/directory is in units of 512 byte blocks,
40 * _NOT_ the filesystem block size!
41 */
42#define INODE_BLOCK_SIZE 512
43
44#define MAX_EXT4_BLOCK_SIZE 4096
45
46/* The two modes the recurse_dir() can be in */
47#define SANITY_CHECK_PASS 1
48#define MARK_INODE_NUMS   2
49#define UPDATE_INODE_NUMS 3
50
51/* Magic numbers to indicate what state the update process is in */
52#define MAGIC_STATE_MARKING_INUMS  0x7000151515565512ll
53#define MAGIC_STATE_UPDATING_INUMS 0x6121131211735123ll
54#define MAGIC_STATE_UPDATING_SB    0x15e1715151558477ll
55
56/* Internal state variables corresponding to the magic numbers */
57#define STATE_UNSET          0
58#define STATE_MARKING_INUMS  1
59#define STATE_UPDATING_INUMS 2
60#define STATE_UPDATING_SB    3
61
62/* Used for automated testing of this programs ability to stop and be restarted wthout error */
63static int bail_phase = 0;
64static int bail_loc = 0;
65static int bail_count = 0;
66static int count = 0;
67
68/* global flags */
69static int verbose = 0;
70static int no_write = 0;
71
72static int new_inodes_per_group = 0;
73
74static int no_write_fixup_state = 0;
75
76static int compute_new_inum(unsigned int old_inum)
77{
78    unsigned int group, offset;
79
80    group = (old_inum - 1) / info.inodes_per_group;
81    offset = (old_inum -1) % info.inodes_per_group;
82
83    return (group * new_inodes_per_group) + offset + 1;
84}
85
86/* Function to read the primary superblock */
87static void read_sb(int fd, struct ext4_super_block *sb)
88{
89    off64_t ret;
90
91    ret = lseek64(fd, 1024, SEEK_SET);
92    if (ret < 0)
93        critical_error_errno("failed to seek to superblock");
94
95    ret = read(fd, sb, sizeof(*sb));
96    if (ret < 0)
97        critical_error_errno("failed to read superblock");
98    if (ret != sizeof(*sb))
99        critical_error("failed to read all of superblock");
100}
101
102/* Function to write a primary or backup superblock at a given offset */
103static void write_sb(int fd, unsigned long long offset, struct ext4_super_block *sb)
104{
105    off64_t ret;
106
107    if (no_write) {
108        return;
109    }
110
111    ret = lseek64(fd, offset, SEEK_SET);
112    if (ret < 0)
113        critical_error_errno("failed to seek to superblock");
114
115    ret = write(fd, sb, sizeof(*sb));
116    if (ret < 0)
117        critical_error_errno("failed to write superblock");
118    if (ret != sizeof(*sb))
119        critical_error("failed to write all of superblock");
120}
121
122static int get_fs_fixup_state(int fd)
123{
124    unsigned long long magic;
125    int ret, len;
126
127    if (no_write) {
128        return no_write_fixup_state;
129    }
130
131    lseek64(fd, 0, SEEK_SET);
132    len = read(fd, &magic, sizeof(magic));
133    if (len != sizeof(magic)) {
134        critical_error("cannot read fixup_state\n");
135    }
136
137    switch (magic) {
138        case MAGIC_STATE_MARKING_INUMS:
139            ret = STATE_MARKING_INUMS;
140            break;
141        case MAGIC_STATE_UPDATING_INUMS:
142            ret = STATE_UPDATING_INUMS;
143            break;
144        case MAGIC_STATE_UPDATING_SB:
145            ret = STATE_UPDATING_SB;
146            break;
147        default:
148            ret = STATE_UNSET;
149    }
150    return ret;
151}
152
153static int set_fs_fixup_state(int fd, int state)
154{
155    unsigned long long magic;
156    struct ext4_super_block sb;
157    int len;
158
159    if (no_write) {
160        no_write_fixup_state = state;
161        return 0;
162    }
163
164    switch (state) {
165        case STATE_MARKING_INUMS:
166            magic = MAGIC_STATE_MARKING_INUMS;
167            break;
168        case STATE_UPDATING_INUMS:
169            magic = MAGIC_STATE_UPDATING_INUMS;
170            break;
171        case STATE_UPDATING_SB:
172            magic = MAGIC_STATE_UPDATING_SB;
173            break;
174        case STATE_UNSET:
175        default:
176            magic = 0ll;
177            break;
178    }
179
180    lseek64(fd, 0, SEEK_SET);
181    len = write(fd, &magic, sizeof(magic));
182    if (len != sizeof(magic)) {
183        critical_error("cannot write fixup_state\n");
184    }
185
186    read_sb(fd, &sb);
187    if (magic) {
188        /* If we are in the process of updating the filesystem, make it unmountable */
189        sb.s_desc_size |= 1;
190    } else {
191        /* we are done, so make the filesystem mountable again */
192        sb.s_desc_size &= ~1;
193    }
194    write_sb(fd, 1024, &sb);
195
196    return 0;
197}
198
199static int read_ext(int fd)
200{
201    off64_t ret;
202    struct ext4_super_block sb;
203
204    read_sb(fd, &sb);
205
206    ext4_parse_sb(&sb);
207
208    if (info.feat_incompat & EXT4_FEATURE_INCOMPAT_RECOVER) {
209        critical_error("Filesystem needs recovery first, mount and unmount to do that\n");
210    }
211
212    /* Clear the low bit which is set while this tool is in progress.
213     * If the tool crashes, it will still be set when we restart.
214     * The low bit is set to make the filesystem unmountable while
215     * it is being fixed up.  Also allow 0, which means the old ext2
216     * size is in use.
217     */
218    if (((sb.s_desc_size & ~1) != sizeof(struct ext2_group_desc)) &&
219        ((sb.s_desc_size & ~1) != 0))
220        critical_error("error: bg_desc_size != sizeof(struct ext2_group_desc)\n");
221
222    ret = lseek64(fd, info.len, SEEK_SET);
223    if (ret < 0)
224        critical_error_errno("failed to seek to end of input image");
225
226    ret = lseek64(fd, info.block_size * (aux_info.first_data_block + 1), SEEK_SET);
227    if (ret < 0)
228        critical_error_errno("failed to seek to block group descriptors");
229
230    ret = read(fd, aux_info.bg_desc, info.block_size * aux_info.bg_desc_blocks);
231    if (ret < 0)
232        critical_error_errno("failed to read block group descriptors");
233    if (ret != (int)info.block_size * (int)aux_info.bg_desc_blocks)
234        critical_error("failed to read all of block group descriptors");
235
236    if (verbose) {
237        printf("Found filesystem with parameters:\n");
238        printf("    Size: %llu\n", info.len);
239        printf("    Block size: %d\n", info.block_size);
240        printf("    Blocks per group: %d\n", info.blocks_per_group);
241        printf("    Inodes per group: %d\n", info.inodes_per_group);
242        printf("    Inode size: %d\n", info.inode_size);
243        printf("    Label: %s\n", info.label);
244        printf("    Blocks: %llu\n", aux_info.len_blocks);
245        printf("    Block groups: %d\n", aux_info.groups);
246        printf("    Reserved block group size: %d\n", info.bg_desc_reserve_blocks);
247        printf("    Used %d/%d inodes and %d/%d blocks\n",
248                aux_info.sb->s_inodes_count - aux_info.sb->s_free_inodes_count,
249                aux_info.sb->s_inodes_count,
250                aux_info.sb->s_blocks_count_lo - aux_info.sb->s_free_blocks_count_lo,
251                aux_info.sb->s_blocks_count_lo);
252    }
253
254    return 0;
255}
256
257static int read_inode(int fd, unsigned int inum, struct ext4_inode *inode)
258{
259    unsigned int bg_num, bg_offset;
260    off64_t inode_offset;
261    int len;
262
263    bg_num = (inum-1) / info.inodes_per_group;
264    bg_offset = (inum-1) % info.inodes_per_group;
265
266    inode_offset = ((unsigned long long)aux_info.bg_desc[bg_num].bg_inode_table * info.block_size) +
267                    (bg_offset * info.inode_size);
268
269    if (lseek64(fd, inode_offset, SEEK_SET) < 0) {
270        critical_error_errno("failed to seek to inode %d\n", inum);
271    }
272
273    len=read(fd, inode, sizeof(*inode));
274    if (len != sizeof(*inode)) {
275        critical_error_errno("failed to read inode %d\n", inum);
276    }
277
278    return 0;
279}
280
281static int read_block(int fd, unsigned long long block_num, void *block)
282{
283    off64_t off;
284    unsigned int len;
285
286    off = block_num * info.block_size;
287
288    if (lseek64(fd, off, SEEK_SET) , 0) {
289        critical_error_errno("failed to seek to block %lld\n", block_num);
290    }
291
292    len=read(fd, block, info.block_size);
293    if (len != info.block_size) {
294        critical_error_errno("failed to read block %lld\n", block_num);
295    }
296
297    return 0;
298}
299
300static int write_block(int fd, unsigned long long block_num, void *block)
301{
302    off64_t off;
303    unsigned int len;
304
305    if (no_write) {
306        return 0;
307    }
308
309    off = block_num * info.block_size;
310
311    if (lseek64(fd, off, SEEK_SET) < 0) {
312        critical_error_errno("failed to seek to block %lld\n", block_num);
313    }
314
315    len=write(fd, block, info.block_size);
316    if (len != info.block_size) {
317        critical_error_errno("failed to write block %lld\n", block_num);
318    }
319
320    return 0;
321}
322
323static int bitmap_get_bit(u8 *bitmap, u32 bit)
324{
325        if (bitmap[bit / 8] & (1 << (bit % 8)))
326                return 1;
327
328        return 0;
329}
330
331static void bitmap_clear_bit(u8 *bitmap, u32 bit)
332{
333        bitmap[bit / 8] &= ~(1 << (bit % 8));
334
335        return;
336}
337
338static void check_inode_bitmap(int fd, unsigned int bg_num)
339{
340    unsigned int inode_bitmap_block_num;
341    unsigned char block[MAX_EXT4_BLOCK_SIZE];
342    int i, bitmap_updated = 0;
343
344    /* Using the bg_num, aux_info.bg_desc[], info.inodes_per_group and
345     * new_inodes_per_group, retrieve the inode bitmap, and make sure
346     * the bits between the old and new size are clear
347     */
348    inode_bitmap_block_num = aux_info.bg_desc[bg_num].bg_inode_bitmap;
349
350    read_block(fd, inode_bitmap_block_num, block);
351
352    for (i = info.inodes_per_group; i < new_inodes_per_group; i++) {
353        if (bitmap_get_bit(block, i)) {
354            bitmap_clear_bit(block, i);
355            bitmap_updated = 1;
356        }
357    }
358
359    if (bitmap_updated) {
360        if (verbose) {
361            printf("Warning: updated inode bitmap for block group %d\n", bg_num);
362        }
363        write_block(fd, inode_bitmap_block_num, block);
364    }
365
366    return;
367}
368
369/* Update the superblock and bgdesc of the specified block group */
370static int update_superblocks_and_bg_desc(int fd, int state)
371{
372    off64_t ret;
373    struct ext4_super_block sb;
374    unsigned int num_block_groups, total_new_inodes;
375    unsigned int i;
376
377
378    read_sb(fd, &sb);
379
380    /* Compute how many more inodes are now available */
381    num_block_groups = DIV_ROUND_UP(aux_info.len_blocks, info.blocks_per_group);
382    total_new_inodes = num_block_groups * (new_inodes_per_group - sb.s_inodes_per_group);
383
384    if (verbose) {
385        printf("created %d additional inodes\n", total_new_inodes);
386    }
387
388    /* Update the free inodes count in each block group descriptor */
389    for (i = 0; i < num_block_groups; i++) {
390       if (state == STATE_UPDATING_SB) {
391           aux_info.bg_desc[i].bg_free_inodes_count += (new_inodes_per_group - sb.s_inodes_per_group);
392       }
393       check_inode_bitmap(fd, i);
394    }
395
396    /* First some sanity checks */
397    if ((sb.s_inodes_count + total_new_inodes) != (new_inodes_per_group * num_block_groups)) {
398        critical_error("Failed sanity check on new inode count\n");
399    }
400    if (new_inodes_per_group % (info.block_size/info.inode_size)) {
401        critical_error("Failed sanity check on new inode per group alignment\n");
402    }
403
404    /* Update the free inodes count in the superblock */
405    sb.s_inodes_count += total_new_inodes;
406    sb.s_free_inodes_count += total_new_inodes;
407    sb.s_inodes_per_group = new_inodes_per_group;
408
409    for (i = 0; i < aux_info.groups; i++) {
410        if (ext4_bg_has_super_block(i)) {
411            unsigned int sb_offset;
412
413            if (i == 0) {
414              /* The first superblock is offset by 1K to leave room for boot sectors */
415              sb_offset = 1024;
416            } else {
417              sb_offset = 0;
418            }
419
420            sb.s_block_group_nr = i;
421            /* Don't write out the backup superblocks with the bit set in the s_desc_size
422             * which prevents the filesystem from mounting.  The bit for the primary
423             * superblock will be cleared on the final call to set_fs_fixup_state() */
424            if (i != 0) {
425                sb.s_desc_size &= ~1;
426            }
427
428            write_sb(fd, (unsigned long long)i * info.blocks_per_group * info.block_size + sb_offset, &sb);
429
430            ret = lseek64(fd, ((unsigned long long)i * info.blocks_per_group * info.block_size) +
431                              (info.block_size * (aux_info.first_data_block + 1)), SEEK_SET);
432            if (ret < 0)
433                critical_error_errno("failed to seek to block group descriptors");
434
435            if (!no_write) {
436                ret = write(fd, aux_info.bg_desc, info.block_size * aux_info.bg_desc_blocks);
437                if (ret < 0)
438                    critical_error_errno("failed to write block group descriptors");
439                if (ret != (int)info.block_size * (int)aux_info.bg_desc_blocks)
440                    critical_error("failed to write all of block group descriptors");
441            }
442        }
443        if ((bail_phase == 4) && ((unsigned int)bail_count == i)) {
444            critical_error("bailing at phase 4\n");
445        }
446    }
447
448    return 0;
449}
450
451
452static int get_direct_blocks(struct ext4_inode *inode, unsigned long long *block_list,
453                                                       unsigned int *count)
454{
455    unsigned int i = 0;
456    unsigned int ret = 0;
457    unsigned int sectors_per_block;
458
459    sectors_per_block = info.block_size / INODE_BLOCK_SIZE;
460    while ((i < (inode->i_blocks_lo / sectors_per_block)) && (i < EXT4_NDIR_BLOCKS)) {
461        block_list[i] = inode->i_block[i];
462        i++;
463    }
464
465    *count += i;
466
467    if ((inode->i_blocks_lo / sectors_per_block) > EXT4_NDIR_BLOCKS) {
468        ret = 1;
469    }
470
471    return ret;
472}
473
474static int get_indirect_blocks(int fd, struct ext4_inode *inode,
475                               unsigned long long *block_list, unsigned int *count)
476{
477    unsigned int i;
478    unsigned int *indirect_block;
479    unsigned int sectors_per_block;
480
481    sectors_per_block = info.block_size / INODE_BLOCK_SIZE;
482
483    indirect_block = (unsigned int *)malloc(info.block_size);
484    if (indirect_block == 0) {
485        critical_error("failed to allocate memory for indirect_block\n");
486    }
487
488    read_block(fd, inode->i_block[EXT4_NDIR_BLOCKS], indirect_block);
489
490    for(i = 0; i < (inode->i_blocks_lo / sectors_per_block - EXT4_NDIR_BLOCKS); i++) {
491       block_list[EXT4_NDIR_BLOCKS+i] = indirect_block[i];
492    }
493
494    *count += i;
495
496    free(indirect_block);
497
498    return 0;
499}
500
501static int get_block_list_indirect(int fd, struct ext4_inode *inode, unsigned long long *block_list)
502{
503    unsigned int count=0;
504
505    if (get_direct_blocks(inode, block_list, &count)) {
506        get_indirect_blocks(fd, inode, block_list, &count);
507    }
508
509    return count;
510}
511
512static int get_extent_ents(struct ext4_extent_header *ext_hdr, unsigned long long *block_list)
513{
514    int i, j;
515    struct ext4_extent *extent;
516    off64_t fs_block_num;
517
518    if (ext_hdr->eh_depth != 0) {
519        critical_error("get_extent_ents called with eh_depth != 0\n");
520    }
521
522    /* The extent entries immediately follow the header, so add 1 to the pointer
523     * and cast it to an extent pointer.
524     */
525    extent = (struct ext4_extent *)(ext_hdr + 1);
526
527    for (i = 0; i < ext_hdr->eh_entries; i++) {
528         fs_block_num = ((off64_t)extent->ee_start_hi << 32) | extent->ee_start_lo;
529         for (j = 0; j < extent->ee_len; j++) {
530             block_list[extent->ee_block+j] = fs_block_num+j;
531         }
532         extent++;
533    }
534
535    return 0;
536}
537
538static int get_extent_idx(int fd, struct ext4_extent_header *ext_hdr, unsigned long long *block_list)
539{
540    int i;
541    struct ext4_extent_idx *extent_idx;
542    struct ext4_extent_header *tmp_ext_hdr;
543    off64_t fs_block_num;
544    unsigned char block[MAX_EXT4_BLOCK_SIZE];
545
546    /* Sanity check */
547    if (ext_hdr->eh_depth == 0) {
548        critical_error("get_extent_idx called with eh_depth == 0\n");
549    }
550
551    /* The extent entries immediately follow the header, so add 1 to the pointer
552     * and cast it to an extent pointer.
553     */
554    extent_idx = (struct ext4_extent_idx *)(ext_hdr + 1);
555
556    for (i = 0; i < ext_hdr->eh_entries; i++) {
557         fs_block_num = ((off64_t)extent_idx->ei_leaf_hi << 32) | extent_idx->ei_leaf_lo;
558         read_block(fd, fs_block_num, block);
559         tmp_ext_hdr = (struct ext4_extent_header *)block;
560
561         if (tmp_ext_hdr->eh_depth == 0) {
562             get_extent_ents(tmp_ext_hdr, block_list); /* leaf node, fill in block_list */
563         } else {
564             get_extent_idx(fd, tmp_ext_hdr, block_list); /* recurse down the tree */
565         }
566    }
567
568    return 0;
569}
570
571static int get_block_list_extents(int fd, struct ext4_inode *inode, unsigned long long *block_list)
572{
573    struct ext4_extent_header *extent_hdr;
574
575    extent_hdr = (struct ext4_extent_header *)inode->i_block;
576
577    if (extent_hdr->eh_magic != EXT4_EXT_MAGIC) {
578        critical_error("extent header has unexpected magic value 0x%4.4x\n",
579                       extent_hdr->eh_magic);
580    }
581
582    if (extent_hdr->eh_depth == 0) {
583         get_extent_ents((struct ext4_extent_header *)inode->i_block, block_list);
584         return 0;
585    }
586
587    get_extent_idx(fd, (struct ext4_extent_header *)inode->i_block, block_list);
588
589    return 0;
590}
591
592static int is_entry_dir(int fd, struct ext4_dir_entry_2 *dirp, int pass)
593{
594    struct ext4_inode inode;
595    int ret = 0;
596
597    if (dirp->file_type == EXT4_FT_DIR) {
598        ret = 1;
599    } else if (dirp->file_type == EXT4_FT_UNKNOWN) {
600        /* Somebody was too lazy to fill in the dir entry,
601         * so we have to go fetch it from the inode. Grrr.
602         */
603        /* if UPDATE_INODE_NUMS pass and the inode high bit is not
604         * set return false so we don't recurse down the tree that is
605         * already updated.  Otherwise, fetch inode, and return answer.
606         */
607        if ((pass == UPDATE_INODE_NUMS) && !(dirp->inode & 0x80000000)) {
608            ret = 0;
609        } else {
610            read_inode(fd, (dirp->inode & 0x7fffffff), &inode);
611            if (S_ISDIR(inode.i_mode)) {
612                ret = 1;
613            }
614        }
615    }
616
617    return ret;
618}
619
620static int recurse_dir(int fd, struct ext4_inode *inode, char *dirbuf, int dirsize, int mode)
621{
622    unsigned long long *block_list;
623    unsigned int num_blocks;
624    struct ext4_dir_entry_2 *dirp, *prev_dirp = 0;
625    char name[256];
626    unsigned int i, leftover_space, is_dir;
627    struct ext4_inode tmp_inode;
628    int tmp_dirsize;
629    char *tmp_dirbuf;
630
631    switch (mode) {
632        case SANITY_CHECK_PASS:
633        case MARK_INODE_NUMS:
634        case UPDATE_INODE_NUMS:
635            break;
636        default:
637            critical_error("recurse_dir() called witn unknown mode!\n");
638    }
639
640    if (dirsize % info.block_size) {
641        critical_error("dirsize %d not a multiple of block_size %d.  This is unexpected!\n",
642                dirsize, info.block_size);
643    }
644
645    num_blocks = dirsize / info.block_size;
646
647    block_list = malloc((num_blocks + 1) * sizeof(*block_list));
648    if (block_list == 0) {
649        critical_error("failed to allocate memory for block_list\n");
650    }
651
652    if (inode->i_flags & EXT4_EXTENTS_FL) {
653        get_block_list_extents(fd, inode, block_list);
654    } else {
655        /* A directory that requires doubly or triply indirect blocks in huge indeed,
656         * and will almost certainly not exist, especially since make_ext4fs only creates
657         * directories with extents, and the kernel will too, but check to make sure the
658         * directory is not that big and give an error if so.  Our limit is 12 direct blocks,
659         * plus block_size/4 singly indirect blocks, which for a filesystem with 4K blocks
660         * is a directory 1036 blocks long, or 4,243,456 bytes long!  Assuming an average
661         * filename length of 20 (which I think is generous) thats 20 + 8 bytes overhead
662         * per entry, or 151,552 entries in the directory!
663         */
664        if (num_blocks > (info.block_size / 4 + EXT4_NDIR_BLOCKS)) {
665            critical_error("Non-extent based directory is too big!\n");
666        }
667        get_block_list_indirect(fd, inode, block_list);
668    }
669
670    /* Read in all the blocks for this directory */
671    for (i = 0; i < num_blocks; i++) {
672        read_block(fd, block_list[i], dirbuf + (i * info.block_size));
673    }
674
675    dirp = (struct ext4_dir_entry_2 *)dirbuf;
676    while (dirp < (struct ext4_dir_entry_2 *)(dirbuf + dirsize)) {
677        count++;
678        leftover_space = (char *)(dirbuf + dirsize) - (char *)dirp;
679        if (((mode == SANITY_CHECK_PASS) || (mode == UPDATE_INODE_NUMS)) &&
680            (leftover_space <= 8) && prev_dirp) {
681            /* This is a bug in an older version of make_ext4fs, where it
682             * didn't properly include the rest of the block in rec_len.
683             * Update rec_len on the previous entry to include the rest of
684             * the block and exit the loop.
685             */
686            if (verbose) {
687                printf("fixing up short rec_len for diretory entry for %s\n", name);
688            }
689            prev_dirp->rec_len += leftover_space;
690            break;
691        }
692
693        if (dirp->inode == 0) {
694            /* This is the last entry in the directory */
695            break;
696        }
697
698        strncpy(name, dirp->name, dirp->name_len);
699        name[dirp->name_len]='\0';
700
701        /* Only recurse on pass UPDATE_INODE_NUMS if the high bit is set.
702         * Otherwise, this inode entry has already been updated
703         * and we'll do the wrong thing.  Also don't recurse on . or ..,
704         * and certainly not on non-directories!
705         */
706        /* Hrm, looks like filesystems made by fastboot on stingray set the file_type
707         * flag, but the lost+found directory has the type set to Unknown, which
708         * seems to imply I need to read the inode and get it.
709         */
710        is_dir = is_entry_dir(fd, dirp, mode);
711        if ( is_dir && (strcmp(name, ".") && strcmp(name, "..")) &&
712            ((mode == SANITY_CHECK_PASS) || (mode == MARK_INODE_NUMS) ||
713              ((mode == UPDATE_INODE_NUMS) && (dirp->inode & 0x80000000))) ) {
714            /* A directory!  Recurse! */
715            read_inode(fd, dirp->inode & 0x7fffffff, &tmp_inode);
716
717            if (!S_ISDIR(tmp_inode.i_mode)) {
718                critical_error("inode %d for name %s does not point to a directory\n",
719                        dirp->inode & 0x7fffffff, name);
720            }
721            if (verbose) {
722                printf("inode %d %s use extents\n", dirp->inode & 0x7fffffff,
723                       (tmp_inode.i_flags & EXT4_EXTENTS_FL) ? "does" : "does not");
724            }
725
726            tmp_dirsize = tmp_inode.i_blocks_lo * INODE_BLOCK_SIZE;
727            if (verbose) {
728                printf("dir size = %d bytes\n", tmp_dirsize);
729            }
730
731            tmp_dirbuf = malloc(tmp_dirsize);
732            if (tmp_dirbuf == 0) {
733                critical_error("failed to allocate memory for tmp_dirbuf\n");
734            }
735
736            recurse_dir(fd, &tmp_inode, tmp_dirbuf, tmp_dirsize, mode);
737
738            free(tmp_dirbuf);
739        }
740
741        if (verbose) {
742            if (is_dir) {
743                printf("Directory %s\n", name);
744            } else {
745                printf("Non-directory %s\n", name);
746            }
747        }
748
749        /* Process entry based on current mode.  Either set high bit or change inode number */
750        if (mode == MARK_INODE_NUMS) {
751            dirp->inode |= 0x80000000;
752        } else if (mode == UPDATE_INODE_NUMS) {
753            if (dirp->inode & 0x80000000) {
754                dirp->inode = compute_new_inum(dirp->inode & 0x7fffffff);
755            }
756        }
757
758        if ((bail_phase == mode) && (bail_loc == 1) && (bail_count == count)) {
759            critical_error("Bailing at phase %d, loc 1 and count %d\n", mode, count);
760        }
761
762        /* Point dirp at the next entry */
763        prev_dirp = dirp;
764        dirp = (struct ext4_dir_entry_2*)((char *)dirp + dirp->rec_len);
765    }
766
767    /* Write out all the blocks for this directory */
768    for (i = 0; i < num_blocks; i++) {
769        write_block(fd, block_list[i], dirbuf + (i * info.block_size));
770        if ((bail_phase == mode) && (bail_loc == 2) && (bail_count <= count)) {
771            critical_error("Bailing at phase %d, loc 2 and count %d\n", mode, count);
772        }
773    }
774
775    free(block_list);
776
777    return 0;
778}
779
780int ext4fixup(char *fsdev)
781{
782    return ext4fixup_internal(fsdev, 0, 0, 0, 0, 0);
783}
784
785int ext4fixup_internal(char *fsdev, int v_flag, int n_flag,
786                       int stop_phase, int stop_loc, int stop_count)
787{
788    int fd;
789    struct ext4_inode root_inode;
790    unsigned int dirsize;
791    char *dirbuf;
792
793    if (setjmp(setjmp_env))
794        return EXIT_FAILURE; /* Handle a call to longjmp() */
795
796    verbose = v_flag;
797    no_write = n_flag;
798
799    bail_phase = stop_phase;
800    bail_loc = stop_loc;
801    bail_count = stop_count;
802
803    fd = open(fsdev, O_RDWR);
804
805    if (fd < 0)
806        critical_error_errno("failed to open filesystem image");
807
808    read_ext(fd);
809
810    if ((info.feat_incompat & EXT4_FEATURE_INCOMPAT_FILETYPE) == 0) {
811        critical_error("Expected filesystem to have filetype flag set\n");
812    }
813
814#if 0 // If we have to fix the directory rec_len issue, we can't use this check
815    /* Check to see if the inodes/group is copacetic */
816    if (info.inodes_per_blockgroup % (info.block_size/info.inode_size) == 0) {
817             /* This filesystem has either already been updated, or was
818              * made correctly.
819              */
820             if (verbose) {
821                 printf("%s: filesystem correct, no work to do\n", me);
822             }
823             exit(0);
824    }
825#endif
826
827    /* Compute what the new value of inodes_per_blockgroup will be when we're done */
828    new_inodes_per_group=ALIGN(info.inodes_per_group,(info.block_size/info.inode_size));
829
830    read_inode(fd, EXT4_ROOT_INO, &root_inode);
831
832    if (!S_ISDIR(root_inode.i_mode)) {
833        critical_error("root inode %d does not point to a directory\n", EXT4_ROOT_INO);
834    }
835    if (verbose) {
836        printf("inode %d %s use extents\n", EXT4_ROOT_INO,
837               (root_inode.i_flags & EXT4_EXTENTS_FL) ? "does" : "does not");
838    }
839
840    dirsize = root_inode.i_blocks_lo * INODE_BLOCK_SIZE;
841    if (verbose) {
842        printf("root dir size = %d bytes\n", dirsize);
843    }
844
845    dirbuf = malloc(dirsize);
846    if (dirbuf == 0) {
847        critical_error("failed to allocate memory for dirbuf\n");
848    }
849
850    /* Perform a sanity check pass first, try to catch any errors that will occur
851     * before we actually change anything, so we don't leave a filesystem in a
852     * corrupted, unrecoverable state.  Set no_write, make it quiet, and do a recurse
853     * pass and a update_superblock pass.  Set flags back to requested state when done.
854     * Only perform sanity check if the state is unset.  If the state is _NOT_ unset,
855     * then the tool has already been run and interrupted, and it presumably ran and
856     * passed sanity checked before it got interrupted.  It is _NOT_ safe to run sanity
857     * check if state is unset because it assumes inodes are to be computed using the
858     * old inodes/group, but some inode numbers may be updated to the new number.
859     */
860    if (get_fs_fixup_state(fd) == STATE_UNSET) {
861        verbose = 0;
862        no_write = 1;
863        recurse_dir(fd, &root_inode, dirbuf, dirsize, SANITY_CHECK_PASS);
864        update_superblocks_and_bg_desc(fd, STATE_UNSET);
865        verbose = v_flag;
866        no_write = n_flag;
867
868        set_fs_fixup_state(fd, STATE_MARKING_INUMS);
869    }
870
871    if (get_fs_fixup_state(fd) == STATE_MARKING_INUMS) {
872        count = 0; /* Reset debugging counter */
873        if (!recurse_dir(fd, &root_inode, dirbuf, dirsize, MARK_INODE_NUMS)) {
874            set_fs_fixup_state(fd, STATE_UPDATING_INUMS);
875        }
876    }
877
878    if (get_fs_fixup_state(fd) == STATE_UPDATING_INUMS) {
879        count = 0; /* Reset debugging counter */
880        if (!recurse_dir(fd, &root_inode, dirbuf, dirsize, UPDATE_INODE_NUMS)) {
881            set_fs_fixup_state(fd, STATE_UPDATING_SB);
882        }
883    }
884
885    if (get_fs_fixup_state(fd) == STATE_UPDATING_SB) {
886        /* set the new inodes/blockgroup number,
887         * and sets the state back to 0.
888         */
889        if (!update_superblocks_and_bg_desc(fd, STATE_UPDATING_SB)) {
890            set_fs_fixup_state(fd, STATE_UNSET);
891        }
892    }
893
894    close(fd);
895
896    return 0;
897}
898