This flag to tdb_open/tdb_open_ex effects creation of a new database:
1) Uses the Jenkins lookup3 hash instead of the old gdbm hash if none is
specified,
2) Places a non-zero field in header->rwlocks, so older versions of TDB will
refuse to open it.
This means that the caller (ie Samba) can set this flag to safely
change the hash function. Versions of TDB from this one on will either
use the correct hash or refuse to open (if a different hash is specified).
Older TDB versions will see the nonzero rwlocks field and refuse to open
it under any conditions.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
(cherry picked (modified) from commit
2dcf76c9247ff02a1779000dbbecdc418473ca41)
Signed-off-by: Stefan Metzmacher <metze@samba.org>
tdb_header_hash(tdb, &newdb->magic1_hash, &newdb->magic2_hash);
tdb_header_hash(tdb, &newdb->magic1_hash, &newdb->magic2_hash);
+ /* Make sure older tdbs (which don't check the magic hash fields)
+ * will refuse to open this TDB. */
+ if (tdb->flags & TDB_INCOMPATIBLE_HASH)
+ newdb->rwlocks = TDB_HASH_RWLOCK_MAGIC;
+
if (tdb->flags & TDB_INTERNAL) {
tdb->map_size = size;
tdb->map_ptr = (char *)newdb;
if (tdb->flags & TDB_INTERNAL) {
tdb->map_size = size;
tdb->map_ptr = (char *)newdb;
return false;
/* Otherwise, try the other inbuilt hash. */
return false;
/* Otherwise, try the other inbuilt hash. */
- tdb->hash_fn = tdb_jenkins_hash;
+ if (tdb->hash_fn == tdb_old_hash)
+ tdb->hash_fn = tdb_jenkins_hash;
+ else
+ tdb->hash_fn = tdb_old_hash;
return check_header_hash(tdb, false, m1, m2);
}
return check_header_hash(tdb, false, m1, m2);
}
tdb->hash_fn = hash_fn;
hash_alg = "the user defined";
} else {
tdb->hash_fn = hash_fn;
hash_alg = "the user defined";
} else {
- tdb->hash_fn = tdb_old_hash;
+ /* This controls what we use when creating a tdb. */
+ if (tdb->flags & TDB_INCOMPATIBLE_HASH) {
+ tdb->hash_fn = tdb_jenkins_hash;
+ } else {
+ tdb->hash_fn = tdb_old_hash;
+ }
hash_alg = "either default";
}
hash_alg = "either default";
}
if (fstat(tdb->fd, &st) == -1)
goto fail;
if (fstat(tdb->fd, &st) == -1)
goto fail;
- if (tdb->header.rwlocks != 0) {
+ if (tdb->header.rwlocks != 0 &&
+ tdb->header.rwlocks != TDB_HASH_RWLOCK_MAGIC) {
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: spinlocks no longer supported\n"));
goto fail;
}
if ((tdb->header.magic1_hash == 0) && (tdb->header.magic2_hash == 0)) {
/* older TDB without magic hash references */
TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: spinlocks no longer supported\n"));
goto fail;
}
if ((tdb->header.magic1_hash == 0) && (tdb->header.magic2_hash == 0)) {
/* older TDB without magic hash references */
+ tdb->hash_fn = tdb_old_hash;
} else if (!check_header_hash(tdb, !hash_fn, &magic1, &magic2)) {
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_open_ex: "
"%s was not created with %s hash function we are using\n"
} else if (!check_header_hash(tdb, !hash_fn, &magic1, &magic2)) {
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_open_ex: "
"%s was not created with %s hash function we are using\n"
#define TDB_FREE_MAGIC (~TDB_MAGIC)
#define TDB_DEAD_MAGIC (0xFEE1DEAD)
#define TDB_RECOVERY_MAGIC (0xf53bc0e7U)
#define TDB_FREE_MAGIC (~TDB_MAGIC)
#define TDB_DEAD_MAGIC (0xFEE1DEAD)
#define TDB_RECOVERY_MAGIC (0xf53bc0e7U)
+#define TDB_RECOVERY_INVALID_MAGIC (0x0)
+#define TDB_HASH_RWLOCK_MAGIC (0xbad1a51U)
#define TDB_ALIGNMENT 4
#define DEFAULT_HASH_SIZE 131
#define FREELIST_TOP (sizeof(struct tdb_header))
#define TDB_ALIGNMENT 4
#define DEFAULT_HASH_SIZE 131
#define FREELIST_TOP (sizeof(struct tdb_header))
#define TDB_NOSYNC 64 /* don't use synchronous transactions */
#define TDB_SEQNUM 128 /* maintain a sequence number */
#define TDB_VOLATILE 256 /* Activate the per-hashchain freelist, default 5 */
#define TDB_NOSYNC 64 /* don't use synchronous transactions */
#define TDB_SEQNUM 128 /* maintain a sequence number */
#define TDB_VOLATILE 256 /* Activate the per-hashchain freelist, default 5 */
+#if 0 /* not backported yet */
+#define TDB_ALLOW_NESTING 512 /* Allow transactions to nest */
+#define TDB_DISALLOW_NESTING 1024 /* Disallow transactions to nest */
+#endif
+#define TDB_INCOMPATIBLE_HASH 2048 /* Better hashing: can't be opened by tdb < 1.2.6. */
#define TDB_ERRCODE(code, ret) ((tdb->ecode = (code)), ret)
#define TDB_ERRCODE(code, ret) ((tdb->ecode = (code)), ret)