mail-index-fsck.c revision d67f6ca7e313e9192268f6bf9952594524655dcd
/* Copyright (c) 2004-2008 Dovecot authors, see the included COPYING file */
#include "lib.h"
#include "ioloop.h"
#include "array.h"
#include "mail-index-private.h"
#include "mail-transaction-log-private.h"
static void mail_index_fsck_error(struct mail_index *index,
const char *fmt, ...) ATTR_FORMAT(2, 3);
static void mail_index_fsck_error(struct mail_index *index,
const char *fmt, ...)
{
va_list va;
va_start(va, fmt);
mail_index_set_error(index, "Fixed index file %s: %s",
index->filepath, t_strdup_vprintf(fmt, va));
va_end(va);
}
#define CHECK(field, oper) \
if (hdr->field oper map->hdr.field) { \
mail_index_fsck_error(index, #field" %u -> %u", \
map->hdr.field, hdr->field); \
}
static void
mail_index_fsck_log_pos(struct mail_index *index, struct mail_index_map *map,
struct mail_index_header *hdr)
{
uint32_t file_seq;
uoff_t file_offset;
mail_transaction_log_get_head(index->log, &file_seq, &file_offset);
if (hdr->log_file_seq < file_seq) {
hdr->log_file_head_offset = hdr->log_file_tail_offset =
sizeof(struct mail_transaction_log_header);
} else {
if (hdr->log_file_head_offset > file_offset)
hdr->log_file_head_offset = file_offset;
if (hdr->log_file_tail_offset > hdr->log_file_head_offset)
hdr->log_file_tail_offset = hdr->log_file_head_offset;
}
hdr->log_file_seq = file_seq;
CHECK(log_file_seq, !=);
if (hdr->log_file_seq == map->hdr.log_file_seq) {
/* don't bother complaining about these if file changed too */
CHECK(log_file_head_offset, !=);
CHECK(log_file_tail_offset, !=);
}
}
static void
mail_index_fsck_header(struct mail_index *index, struct mail_index_map *map,
struct mail_index_header *hdr)
{
/* mail_index_map_check_header() has already checked that the index
isn't completely broken. */
if (hdr->uid_validity == 0 && hdr->next_uid != 1)
hdr->uid_validity = ioloop_time;
if (index->log->head != NULL)
mail_index_fsck_log_pos(index, map, hdr);
}
static bool
array_has_name(const ARRAY_TYPE(const_string) *names, const char *name)
{
const char *const *str;
unsigned int i, count;
str = array_get(names, &count);
for (i = 0; i < count; i++) {
if (strcmp(str[i], name) == 0)
return TRUE;
}
return FALSE;
}
static unsigned int
mail_index_fsck_find_keyword_count(struct mail_index_map *map,
const struct mail_index_ext_header *ext_hdr)
{
const struct mail_index_record *rec;
const uint8_t *kw;
unsigned int r, i, j, cur, max = 0, kw_pos, kw_size;
kw_pos = ext_hdr->record_offset;
kw_size = ext_hdr->record_size;
rec = map->rec_map->records;
for (r = 0; r < map->rec_map->records_count; r++) {
kw = CONST_PTR_OFFSET(rec, kw_pos);
for (i = cur = 0; i < kw_size; i++) {
if (kw[i] != 0) {
for (j = 0; j < 8; j++) {
if ((kw[i] & (1 << j)) != 0)
cur = i * 8 + j + 1;
}
}
}
if (cur > max) {
max = cur;
if (max == kw_size*8)
return max;
}
rec = CONST_PTR_OFFSET(rec, map->hdr.record_size);
}
return max;
}
static bool
keyword_name_is_valid(const char *buffer, unsigned int pos, unsigned int size)
{
for (; pos < size; pos++) {
if (buffer[pos] == '\0')
return TRUE;
if (((unsigned char)buffer[pos] & 0x7f) < 32) {
/* control characters aren't valid */
return FALSE;
}
}
return FALSE;
}
static void
mail_index_fsck_keywords(struct mail_index *index, struct mail_index_map *map,
struct mail_index_header *hdr,
const struct mail_index_ext_header *ext_hdr,
unsigned int ext_offset, unsigned int *offset_p)
{
const struct mail_index_keyword_header *kw_hdr;
struct mail_index_keyword_header *new_kw_hdr;
const struct mail_index_keyword_header_rec *kw_rec;
struct mail_index_keyword_header_rec new_kw_rec;
const char *name, *name_buffer, **name_array;
unsigned int i, j, name_pos, name_size, rec_pos, hdr_offset, diff;
unsigned int changed_count, keywords_count, name_base_pos;
ARRAY_TYPE(const_string) names;
buffer_t *dest;
bool changed = FALSE;
hdr_offset = ext_offset +
mail_index_map_ext_hdr_offset(sizeof("keywords")-1);
kw_hdr = CONST_PTR_OFFSET(map->hdr_base, hdr_offset);
keywords_count = kw_hdr->keywords_count;
kw_rec = (const void *)(kw_hdr + 1);
name_buffer = (const char *)(kw_rec + keywords_count);
name_pos = (size_t)(name_buffer - (const char *)kw_hdr);
if (name_pos > ext_hdr->hdr_size) {
/* the header is completely broken */
keywords_count =
mail_index_fsck_find_keyword_count(map, ext_hdr);
mail_index_fsck_error(index, "Assuming keywords_count = %u",
keywords_count);
kw_rec = NULL;
name_size = 0;
changed = TRUE;
} else {
name_size = ext_hdr->hdr_size - name_pos;
}
/* create keyword name array. invalid keywords are added as
empty strings */
t_array_init(&names, keywords_count);
for (i = 0; i < keywords_count; i++) {
if (name_size == 0 ||
!keyword_name_is_valid(name_buffer, kw_rec[i].name_offset,
name_size))
name = "";
else
name = name_buffer + kw_rec[i].name_offset;
if (*name != '\0' && array_has_name(&names, name)) {
/* duplicate */
name = "";
}
array_append(&names, &name, 1);
}
/* give new names to invalid keywords */
changed_count = 0;
name_array = array_idx_modifiable(&names, 0);
for (i = j = 0; i < keywords_count; i++) {
while (name_array[i][0] == '\0') {
name = t_strdup_printf("unknown-%d", j++);
if (!array_has_name(&names, name)) {
name_array[i] = name;
changed = TRUE;
changed_count++;
}
}
}
if (!changed) {
/* nothing was broken */
return;
}
mail_index_fsck_error(index, "Renamed %u keywords to unknown-*",
changed_count);
dest = buffer_create_dynamic(default_pool,
I_MAX(ext_hdr->hdr_size, 128));
new_kw_hdr = buffer_append_space_unsafe(dest, sizeof(*new_kw_hdr));
new_kw_hdr->keywords_count = keywords_count;
/* add keyword records so we can start appending names directly */
rec_pos = dest->used;
memset(&new_kw_rec, 0, sizeof(new_kw_rec));
buffer_append_space_unsafe(dest, keywords_count * sizeof(*kw_rec));
/* write the actual records and names */
name_base_pos = dest->used;
for (i = 0; i < keywords_count; i++) {
new_kw_rec.name_offset = dest->used - name_base_pos;
buffer_write(dest, rec_pos, &new_kw_rec, sizeof(new_kw_rec));
rec_pos += sizeof(*kw_rec);
buffer_append(dest, name_array[i], strlen(name_array[i]) + 1);
}
/* keep the header size at least the same size as before */
if (dest->used < ext_hdr->hdr_size)
buffer_append_zero(dest, ext_hdr->hdr_size - dest->used);
if (dest->used > ext_hdr->hdr_size) {
/* need to resize the header */
struct mail_index_ext_header new_ext_hdr;
diff = dest->used - ext_hdr->hdr_size;
buffer_copy(map->hdr_copy_buf, hdr_offset + diff,
map->hdr_copy_buf, hdr_offset, (size_t)-1);
map->hdr_base = map->hdr_copy_buf->data;
hdr->header_size += diff;
*offset_p += diff;
new_ext_hdr = *ext_hdr;
new_ext_hdr.hdr_size += diff;
buffer_write(map->hdr_copy_buf, ext_offset,
&new_ext_hdr, sizeof(new_ext_hdr));
}
i_assert(hdr_offset + dest->used <= map->hdr_copy_buf->used);
buffer_write(map->hdr_copy_buf, hdr_offset, dest->data, dest->used);
/* keywords changed unexpectedly, so all views are broken now */
index->inconsistency_id++;
buffer_free(&dest);
}
static void
mail_index_fsck_extensions(struct mail_index *index, struct mail_index_map *map,
struct mail_index_header *hdr)
{
const struct mail_index_ext_header *ext_hdr;
ARRAY_TYPE(const_string) names;
const char *name, *error;
unsigned int offset, ext_offset, i;
t_array_init(&names, 64);
offset = MAIL_INDEX_HEADER_SIZE_ALIGN(hdr->base_header_size);
for (i = 0; offset < hdr->header_size; i++) {
ext_offset = offset;
if (mail_index_map_ext_get_next(map, &offset,
&ext_hdr, &name) < 0) {
/* the extension continued outside header, drop it */
mail_index_fsck_error(index,
"Dropped extension #%d (%s) "
"with invalid header size",
i, name);
hdr->header_size = ext_offset;
break;
}
if (mail_index_map_ext_hdr_check(hdr, ext_hdr, name,
&error) < 0) {
mail_index_fsck_error(index,
"Dropped broken extension #%d (%s)", i, name);
} else if (array_has_name(&names, name)) {
mail_index_fsck_error(index,
"Dropped duplicate extension %s", name);
} else {
/* name may change if header buffer is changed */
name = t_strdup(name);
if (strcmp(name, "keywords") == 0) {
mail_index_fsck_keywords(index, map, hdr,
ext_hdr, ext_offset,
&offset);
}
array_append(&names, &name, 1);
continue;
}
/* drop the field */
hdr->header_size -= offset - ext_offset;
buffer_copy(map->hdr_copy_buf, ext_offset,
map->hdr_copy_buf, offset, (size_t)-1);
buffer_set_used_size(map->hdr_copy_buf, hdr->header_size);
map->hdr_base = map->hdr_copy_buf->data;
offset = ext_offset;
}
}
static void
mail_index_fsck_records(struct mail_index *index, struct mail_index_map *map,
struct mail_index_header *hdr)
{
struct mail_index_record *rec, *next_rec;
uint32_t i, last_uid;
bool logged_unordered_uids = FALSE, logged_zero_uids = FALSE;
bool records_dropped = FALSE;
hdr->messages_count = 0;
hdr->seen_messages_count = 0;
hdr->deleted_messages_count = 0;
hdr->first_unseen_uid_lowwater = 0;
hdr->first_deleted_uid_lowwater = 0;
rec = map->rec_map->records; last_uid = 0;
for (i = 0; i < map->rec_map->records_count; ) {
next_rec = PTR_OFFSET(rec, hdr->record_size);
if (rec->uid <= last_uid) {
/* log an error once, and skip this record */
if (rec->uid == 0) {
if (!logged_zero_uids) {
mail_index_fsck_error(index,
"Record UIDs have zeroes");
logged_zero_uids = TRUE;
}
} else {
if (!logged_unordered_uids) {
mail_index_fsck_error(index,
"Record UIDs unordered");
logged_unordered_uids = TRUE;
}
}
/* not the fastest way when we're skipping lots of
records, but this should happen rarely so don't
bother optimizing. */
memmove(rec, next_rec, hdr->record_size *
(map->rec_map->records_count - i - 1));
map->rec_map->records_count--;
records_dropped = TRUE;
continue;
}
hdr->messages_count++;
if ((rec->flags & MAIL_SEEN) != 0)
hdr->seen_messages_count++;
if ((rec->flags & MAIL_DELETED) != 0)
hdr->deleted_messages_count++;
if ((rec->flags & MAIL_SEEN) == 0 &&
hdr->first_unseen_uid_lowwater == 0)
hdr->first_unseen_uid_lowwater = rec->uid;
if ((rec->flags & MAIL_DELETED) != 0 &&
hdr->first_deleted_uid_lowwater == 0)
hdr->first_deleted_uid_lowwater = rec->uid;
last_uid = rec->uid;
rec = next_rec;
i++;
}
if (records_dropped) {
/* all existing views are broken now */
index->inconsistency_id++;
}
if (hdr->next_uid <= last_uid) {
mail_index_fsck_error(index, "next_uid %u -> %u",
hdr->next_uid, last_uid+1);
hdr->next_uid = last_uid+1;
}
if (hdr->first_unseen_uid_lowwater == 0)
hdr->first_unseen_uid_lowwater = hdr->next_uid;
if (hdr->first_deleted_uid_lowwater == 0)
hdr->first_deleted_uid_lowwater = hdr->next_uid;
if (hdr->first_recent_uid > hdr->next_uid)
hdr->first_recent_uid = hdr->next_uid;
if (hdr->first_recent_uid == 0)
hdr->first_recent_uid = 1;
CHECK(uid_validity, !=);
CHECK(messages_count, !=);
CHECK(seen_messages_count, !=);
CHECK(deleted_messages_count, !=);
CHECK(first_unseen_uid_lowwater, <);
CHECK(first_deleted_uid_lowwater, <);
CHECK(first_recent_uid, !=);
}
static void
mail_index_fsck_map(struct mail_index *index, struct mail_index_map *map)
{
struct mail_index_header hdr;
if (index->log->head != NULL) {
/* Remember the log head position. If we go back in the index's
head offset, ignore errors in the log up to this offset. */
mail_transaction_log_get_head(index->log,
&index->fsck_log_head_file_seq,
&index->fsck_log_head_file_offset);
}
hdr = map->hdr;
mail_index_fsck_header(index, map, &hdr);
mail_index_fsck_extensions(index, map, &hdr);
mail_index_fsck_records(index, map, &hdr);
map->hdr = hdr;
}
int mail_index_fsck(struct mail_index *index)
{
bool orig_locked = index->log_locked;
struct mail_index_map *map;
uint32_t file_seq;
uoff_t file_offset;
i_warning("fscking index file %s", index->filepath);
if (index->log->head == NULL) {
/* we're trying to open the index files, but there wasn't
any .log file. this should be rare, so just fsck it without
locking. */
orig_locked = TRUE;
}
if (!orig_locked) {
if (mail_transaction_log_sync_lock(index->log, &file_seq,
&file_offset) < 0)
return -1;
}
map = mail_index_map_clone(index->map);
mail_index_unmap(&index->map);
index->map = map;
T_BEGIN {
mail_index_fsck_map(index, map);
} T_END;
map->write_base_header = TRUE;
map->write_atomic = TRUE;
mail_index_write(index, FALSE);
if (!orig_locked)
mail_transaction_log_sync_unlock(index->log);
return 0;
}
void mail_index_fsck_locked(struct mail_index *index)
{
int ret;
i_assert(index->log_locked);
ret = mail_index_fsck(index);
i_assert(ret == 0);
}