/*
Trivial Database 2: free list/block handling
Copyright (C) Rusty Russell 2010
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 3 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, see .
*/
#include "private.h"
#include
#include
/* We keep an ordered array of offsets. */
static bool append(tdb_off_t **arr, size_t *num, tdb_off_t off)
{
tdb_off_t *new = realloc(*arr, (*num + 1) * sizeof(tdb_off_t));
if (!new)
return false;
new[(*num)++] = off;
*arr = new;
return true;
}
static bool check_header(struct tdb_context *tdb)
{
uint64_t hash_test;
hash_test = TDB_HASH_MAGIC;
hash_test = tdb_hash(tdb, &hash_test, sizeof(hash_test));
if (tdb->header.hash_test != hash_test) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"check: hash test %llu should be %llu\n",
tdb->header.hash_test, hash_test);
return false;
}
if (strcmp(tdb->header.magic_food, TDB_MAGIC_FOOD) != 0) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"check: bad magic '%.*s'\n",
sizeof(tdb->header.magic_food),
tdb->header.magic_food);
return false;
}
if (tdb->header.v.hash_bits < INITIAL_HASH_BITS) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"check: bad hash bits %llu\n",
(long long)tdb->header.v.hash_bits);
return false;
}
if (tdb->header.v.zone_bits < INITIAL_ZONE_BITS) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"check: bad zone_bits %llu\n",
(long long)tdb->header.v.zone_bits);
return false;
}
if (tdb->header.v.free_buckets < INITIAL_FREE_BUCKETS) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"check: bad free_buckets %llu\n",
(long long)tdb->header.v.free_buckets);
return false;
}
if ((1ULL << tdb->header.v.zone_bits) * tdb->header.v.num_zones
< tdb->map_size) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"check: %llu zones size %llu don't cover %llu\n",
(long long)(1ULL << tdb->header.v.zone_bits),
(long long)tdb->header.v.num_zones,
(long long)tdb->map_size);
return false;
}
/* We check hash_off and free_off later. */
/* Don't check reserved: they *can* be used later. */
return true;
}
static int off_cmp(const tdb_off_t *a, const tdb_off_t *b)
{
/* Can overflow an int. */
return a > b ? 1
: a < b ? -1
: 0;
}
static bool check_hash_list(struct tdb_context *tdb,
tdb_off_t used[],
size_t num_used)
{
struct tdb_used_record rec;
tdb_len_t hashlen, i, num_nonzero;
tdb_off_t h;
size_t num_found;
hashlen = sizeof(tdb_off_t) << tdb->header.v.hash_bits;
if (tdb_read_convert(tdb, tdb->header.v.hash_off - sizeof(rec),
&rec, sizeof(rec)) == -1)
return false;
if (rec_data_length(&rec) != hashlen) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"tdb_check: Bad hash table length %llu vs %llu\n",
(long long)rec_data_length(&rec),
(long long)hashlen);
return false;
}
if (rec_key_length(&rec) != 0) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"tdb_check: Bad hash table key length %llu\n",
(long long)rec_key_length(&rec));
return false;
}
if (rec_hash(&rec) != 0) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"tdb_check: Bad hash table hash value %llu\n",
(long long)rec_hash(&rec));
return false;
}
num_found = 0;
num_nonzero = 0;
for (i = 0, h = tdb->header.v.hash_off;
i < (1ULL << tdb->header.v.hash_bits);
i++, h += sizeof(tdb_off_t)) {
tdb_off_t off, *p, pos;
struct tdb_used_record rec;
uint64_t hash;
off = tdb_read_off(tdb, h);
if (off == TDB_OFF_ERR)
return false;
if (!off) {
num_nonzero = 0;
continue;
}
/* FIXME: Check hash bits */
p = asearch(&off, used, num_used, off_cmp);
if (!p) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"tdb_check: Invalid offset %llu in hash\n",
(long long)off);
return false;
}
/* Mark it invalid. */
*p ^= 1;
num_found++;
if (tdb_read_convert(tdb, off, &rec, sizeof(rec)) == -1)
return false;
/* Check it is hashed correctly. */
hash = hash_record(tdb, off);
/* Top bits must match header. */
if (hash >> (64 - 11) != rec_hash(&rec)) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"tdb_check: Bad hash magic at offset %llu"
" (0x%llx vs 0x%llx)\n",
(long long)off,
(long long)hash, (long long)rec_hash(&rec));
return false;
}
/* It must be in the right place in hash array. */
pos = hash & ((1ULL << tdb->header.v.hash_bits)-1);
if (pos < i - num_nonzero || pos > i) {
/* Could be wrap from end of array? FIXME: check? */
if (i != num_nonzero) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"tdb_check: Bad hash position %llu at"
" offset %llu hash 0x%llx\n",
(long long)i,
(long long)off,
(long long)hash);
return false;
}
}
num_nonzero++;
}
if (num_found != num_used) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"tdb_check: Not all entries are in hash\n");
return false;
}
return true;
}
static bool check_free(struct tdb_context *tdb,
tdb_off_t off,
const struct tdb_free_record *frec,
tdb_off_t prev,
tdb_off_t zone, unsigned int bucket)
{
if (frec->magic != TDB_FREE_MAGIC) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"tdb_check: offset %llu bad magic 0x%llx\n",
(long long)off, (long long)frec->magic);
return false;
}
if (tdb->methods->oob(tdb, off
+ frec->data_len-sizeof(struct tdb_used_record),
true))
return false;
if (zone_of(tdb, off) != zone) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"tdb_check: offset %llu in wrong zone %llu vs %llu\n",
(long long)off,
(long long)zone, (long long)zone_of(tdb, off));
return false;
}
if (size_to_bucket(tdb, frec->data_len) != bucket) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"tdb_check: offset %llu in wrong bucket %u vs %u\n",
(long long)off,
bucket, size_to_bucket(tdb, frec->data_len));
return false;
}
if (prev != frec->prev) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"tdb_check: offset %llu bad prev %llu vs %llu\n",
(long long)off,
(long long)prev, (long long)frec->prev);
return false;
}
return true;
}
static bool check_free_list(struct tdb_context *tdb,
tdb_off_t free[],
size_t num_free)
{
struct tdb_used_record rec;
tdb_len_t freelen, i, j;
tdb_off_t h;
size_t num_found;
freelen = sizeof(tdb_off_t) * tdb->header.v.num_zones
* (tdb->header.v.free_buckets + 1);
if (tdb_read_convert(tdb, tdb->header.v.free_off - sizeof(rec),
&rec, sizeof(rec)) == -1)
return false;
if (rec_data_length(&rec) != freelen) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"tdb_check: Bad free table length %llu vs %llu\n",
(long long)rec_data_length(&rec),
(long long)freelen);
return false;
}
if (rec_key_length(&rec) != 0) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"tdb_check: Bad free table key length %llu\n",
(long long)rec_key_length(&rec));
return false;
}
if (rec_hash(&rec) != 0) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"tdb_check: Bad free table hash value %llu\n",
(long long)rec_hash(&rec));
return false;
}
num_found = 0;
h = tdb->header.v.free_off;
for (i = 0; i < tdb->header.v.num_zones; i++) {
for (j = 0; j <= tdb->header.v.free_buckets;
j++, h += sizeof(tdb_off_t)) {
tdb_off_t off, prev = 0, *p;
struct tdb_free_record f;
for (off = tdb_read_off(tdb, h); off; off = f.next) {
if (off == TDB_OFF_ERR)
return false;
if (tdb_read_convert(tdb, off, &f, sizeof(f)))
return false;
if (!check_free(tdb, off, &f, prev, i, j))
return false;
/* FIXME: Check hash bits */
p = asearch(&off, free, num_free, off_cmp);
if (!p) {
tdb->log(tdb, TDB_DEBUG_ERROR,
tdb->log_priv,
"tdb_check: Invalid offset"
" %llu in free table\n",
(long long)off);
return false;
}
/* Mark it invalid. */
*p ^= 1;
num_found++;
prev = off;
}
}
}
if (num_found != num_free) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"tdb_check: Not all entries are in free table\n");
return false;
}
return true;
}
/* FIXME: call check() function. */
int tdb_check(struct tdb_context *tdb,
int (*check)(TDB_DATA key, TDB_DATA data, void *private_data),
void *private_data)
{
tdb_off_t *free = NULL, *used = NULL, off;
tdb_len_t len;
size_t num_free = 0, num_used = 0;
bool hash_found = false, free_found = false;
if (tdb_allrecord_lock(tdb, F_RDLCK, TDB_LOCK_WAIT, false) != 0)
return -1;
update_header(tdb);
if (!check_header(tdb))
goto fail;
/* First we do a linear scan, checking all records. */
for (off = sizeof(struct tdb_header);
off < tdb->map_size;
off += len) {
union {
struct tdb_used_record u;
struct tdb_free_record f;
} pad, *p;
p = tdb_get(tdb, off, &pad, sizeof(pad));
if (!p)
goto fail;
if (p->f.magic == TDB_FREE_MAGIC) {
/* This record is free! */
if (!append(&free, &num_free, off))
goto fail;
len = sizeof(p->u) + p->f.data_len;
if (tdb->methods->oob(tdb, off + len, false))
goto fail;
} else {
uint64_t klen, dlen, extra;
/* This record is used! */
if (rec_magic(&p->u) != TDB_MAGIC) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"tdb_check: Bad magic 0x%llx"
" at offset %llu\n",
(long long)rec_magic(&p->u),
(long long)off);
goto fail;
}
if (!append(&used, &num_used, off))
goto fail;
klen = rec_key_length(&p->u);
dlen = rec_data_length(&p->u);
extra = rec_extra_padding(&p->u);
len = sizeof(p->u) + klen + dlen + extra;
if (tdb->methods->oob(tdb, off + len, false))
goto fail;
if (off + sizeof(p->u) == tdb->header.v.hash_off) {
hash_found = true;
} else if (off + sizeof(p->u)
== tdb->header.v.free_off) {
free_found = true;
}
}
}
if (!hash_found) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"tdb_check: hash table not found at %llu\n",
(long long)tdb->header.v.hash_off);
goto fail;
}
if (!free_found) {
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"tdb_check: free table not found at %llu\n",
(long long)tdb->header.v.free_off);
goto fail;
}
/* FIXME: Check key uniqueness? */
if (!check_hash_list(tdb, used, num_used))
goto fail;
if (!check_free_list(tdb, free, num_free))
goto fail;
tdb_allrecord_unlock(tdb, F_RDLCK);
return true;
fail:
tdb_allrecord_unlock(tdb, F_RDLCK);
return false;
}