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-rw-r--r--lib/dbwrap/dbwrap.c701
1 files changed, 701 insertions, 0 deletions
diff --git a/lib/dbwrap/dbwrap.c b/lib/dbwrap/dbwrap.c
new file mode 100644
index 0000000..7555efa
--- /dev/null
+++ b/lib/dbwrap/dbwrap.c
@@ -0,0 +1,701 @@
+/*
+ Unix SMB/CIFS implementation.
+ Database interface wrapper
+ Copyright (C) Jim McDonough <jmcd@us.ibm.com> 2006
+
+ Major code contributions from Aleksey Fedoseev (fedoseev@ru.ibm.com)
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "replace.h"
+#include "lib/util/debug.h"
+#include "lib/util/fault.h"
+#include "lib/util/talloc_stack.h"
+#include "dbwrap/dbwrap.h"
+#include "dbwrap/dbwrap_private.h"
+#include "lib/util/util_tdb.h"
+#include "lib/util/tevent_ntstatus.h"
+
+/*
+ * Fall back using fetch if no genuine exists operation is provided
+ */
+
+static int dbwrap_fallback_exists(struct db_context *db, TDB_DATA key)
+{
+ NTSTATUS status = dbwrap_parse_record(db, key, NULL, NULL);
+ return NT_STATUS_IS_OK(status) ? 1 : 0;
+}
+
+static int delete_record(struct db_record *rec, void *data)
+{
+ NTSTATUS status = dbwrap_record_delete(rec);
+ return NT_STATUS_IS_OK(status) ? 0 : -1;
+}
+
+/*
+ * Fallback wipe implementation using traverse and delete if no genuine
+ * wipe operation is provided
+ */
+static int dbwrap_fallback_wipe(struct db_context *db)
+{
+ NTSTATUS status = dbwrap_trans_traverse(db, delete_record, NULL);
+ return NT_STATUS_IS_OK(status) ? 0 : -1;
+}
+
+static int do_nothing(struct db_record *rec, void *unused)
+{
+ return 0;
+}
+
+/*
+ * Fallback check operation: just traverse.
+ */
+static int dbwrap_fallback_check(struct db_context *db)
+{
+ NTSTATUS status = dbwrap_traverse_read(db, do_nothing, NULL, NULL);
+ return NT_STATUS_IS_OK(status) ? 0 : -1;
+}
+
+/*
+ * Wrapper functions for the backend methods
+ */
+
+TDB_DATA dbwrap_record_get_key(const struct db_record *rec)
+{
+ return rec->key;
+}
+
+TDB_DATA dbwrap_record_get_value(const struct db_record *rec)
+{
+ SMB_ASSERT(rec->value_valid);
+ return rec->value;
+}
+
+NTSTATUS dbwrap_record_storev(struct db_record *rec,
+ const TDB_DATA *dbufs, int num_dbufs, int flags)
+{
+ NTSTATUS status;
+
+ /*
+ * Invalidate before rec->storev() is called, give
+ * rec->storev() the chance to re-validate rec->value.
+ */
+ rec->value_valid = false;
+
+ status = rec->storev(rec, dbufs, num_dbufs, flags);
+ if (!NT_STATUS_IS_OK(status)) {
+ return status;
+ }
+ return NT_STATUS_OK;
+}
+
+NTSTATUS dbwrap_record_store(struct db_record *rec, TDB_DATA data, int flags)
+{
+ return dbwrap_record_storev(rec, &data, 1, flags);
+}
+
+NTSTATUS dbwrap_record_delete(struct db_record *rec)
+{
+ NTSTATUS status;
+
+ status = rec->delete_rec(rec);
+ if (!NT_STATUS_IS_OK(status)) {
+ return status;
+ }
+
+ rec->value = tdb_null;
+
+ return NT_STATUS_OK;
+}
+
+const char *locked_dbs[DBWRAP_LOCK_ORDER_MAX];
+
+static void debug_lock_order(int level)
+{
+ int i;
+ DEBUG(level, ("lock order: "));
+ for (i=0; i<DBWRAP_LOCK_ORDER_MAX; i++) {
+ DEBUGADD(level,
+ (" %d:%s",
+ i + 1,
+ locked_dbs[i] ? locked_dbs[i] : "<none>"));
+ }
+ DEBUGADD(level, ("\n"));
+}
+
+void dbwrap_lock_order_lock(const char *db_name,
+ enum dbwrap_lock_order lock_order)
+{
+ int idx;
+
+ DBG_INFO("check lock order %d for %s\n",
+ (int)lock_order,
+ db_name);
+
+ if (!DBWRAP_LOCK_ORDER_VALID(lock_order)) {
+ DBG_ERR("Invalid lock order %d of %s\n",
+ lock_order,
+ db_name);
+ smb_panic("lock order violation");
+ }
+
+ for (idx=lock_order-1; idx<DBWRAP_LOCK_ORDER_MAX; idx++) {
+ if (locked_dbs[idx] != NULL) {
+ DBG_ERR("Lock order violation: Trying %s at %d while "
+ "%s at %d is locked\n",
+ db_name,
+ (int)lock_order,
+ locked_dbs[idx],
+ idx + 1);
+ debug_lock_order(0);
+ smb_panic("lock order violation");
+ }
+ }
+
+ locked_dbs[lock_order-1] = db_name;
+
+ debug_lock_order(10);
+}
+
+void dbwrap_lock_order_unlock(const char *db_name,
+ enum dbwrap_lock_order lock_order)
+{
+ DBG_INFO("release lock order %d for %s\n",
+ (int)lock_order,
+ db_name);
+
+ if (!DBWRAP_LOCK_ORDER_VALID(lock_order)) {
+ DBG_ERR("Invalid lock order %d of %s\n",
+ lock_order,
+ db_name);
+ smb_panic("lock order violation");
+ }
+
+ if (locked_dbs[lock_order-1] == NULL) {
+ DBG_ERR("db %s at order %d unlocked\n",
+ db_name,
+ (int)lock_order);
+ smb_panic("lock order violation");
+ }
+
+ if (locked_dbs[lock_order-1] != db_name) {
+ DBG_ERR("locked db at lock order %d is %s, expected %s\n",
+ (int)lock_order,
+ locked_dbs[lock_order-1],
+ db_name);
+ smb_panic("lock order violation");
+ }
+
+ locked_dbs[lock_order-1] = NULL;
+}
+
+struct dbwrap_lock_order_state {
+ struct db_context *db;
+};
+
+static int dbwrap_lock_order_state_destructor(
+ struct dbwrap_lock_order_state *s)
+{
+ struct db_context *db = s->db;
+ dbwrap_lock_order_unlock(db->name, db->lock_order);
+ return 0;
+}
+
+static struct dbwrap_lock_order_state *dbwrap_check_lock_order(
+ struct db_context *db, TALLOC_CTX *mem_ctx)
+{
+ struct dbwrap_lock_order_state *state;
+
+ state = talloc(mem_ctx, struct dbwrap_lock_order_state);
+ if (state == NULL) {
+ DBG_WARNING("talloc failed\n");
+ return NULL;
+ }
+ state->db = db;
+
+ dbwrap_lock_order_lock(db->name, db->lock_order);
+ talloc_set_destructor(state, dbwrap_lock_order_state_destructor);
+
+ return state;
+}
+
+static struct db_record *dbwrap_fetch_locked_internal(
+ struct db_context *db, TALLOC_CTX *mem_ctx, TDB_DATA key,
+ struct db_record *(*db_fn)(struct db_context *db, TALLOC_CTX *mem_ctx,
+ TDB_DATA key))
+{
+ struct db_record *rec;
+ struct dbwrap_lock_order_state *lock_order = NULL;
+
+ if (db->lock_order != DBWRAP_LOCK_ORDER_NONE) {
+ lock_order = dbwrap_check_lock_order(db, mem_ctx);
+ if (lock_order == NULL) {
+ return NULL;
+ }
+ }
+ rec = db_fn(db, mem_ctx, key);
+ if (rec == NULL) {
+ TALLOC_FREE(lock_order);
+ return NULL;
+ }
+ (void)talloc_steal(rec, lock_order);
+ rec->db = db;
+ return rec;
+}
+
+struct db_record *dbwrap_fetch_locked(struct db_context *db,
+ TALLOC_CTX *mem_ctx,
+ TDB_DATA key)
+{
+ return dbwrap_fetch_locked_internal(db, mem_ctx, key,
+ db->fetch_locked);
+}
+
+struct db_context *dbwrap_record_get_db(struct db_record *rec)
+{
+ return rec->db;
+}
+
+struct dbwrap_fetch_state {
+ TALLOC_CTX *mem_ctx;
+ TDB_DATA data;
+};
+
+static void dbwrap_fetch_parser(TDB_DATA key, TDB_DATA data,
+ void *private_data)
+{
+ struct dbwrap_fetch_state *state =
+ (struct dbwrap_fetch_state *)private_data;
+
+ state->data.dsize = data.dsize;
+ state->data.dptr = (uint8_t *)talloc_memdup(state->mem_ctx, data.dptr,
+ data.dsize);
+}
+
+NTSTATUS dbwrap_fetch(struct db_context *db, TALLOC_CTX *mem_ctx,
+ TDB_DATA key, TDB_DATA *value)
+{
+ struct dbwrap_fetch_state state;
+ NTSTATUS status;
+
+ if (value == NULL) {
+ return NT_STATUS_INVALID_PARAMETER;
+ }
+
+ state.mem_ctx = mem_ctx;
+
+ status = dbwrap_parse_record(db, key, dbwrap_fetch_parser, &state);
+ if (!NT_STATUS_IS_OK(status)) {
+ return status;
+ }
+ if ((state.data.dsize != 0) && (state.data.dptr == NULL)) {
+ return NT_STATUS_NO_MEMORY;
+ }
+ *value = state.data;
+ return NT_STATUS_OK;
+}
+
+bool dbwrap_exists(struct db_context *db, TDB_DATA key)
+{
+ int result;
+ if (db->exists != NULL) {
+ result = db->exists(db, key);
+ } else {
+ result = dbwrap_fallback_exists(db,key);
+ }
+ return (result == 1);
+}
+
+struct dbwrap_store_state {
+ TDB_DATA data;
+ int flags;
+ NTSTATUS status;
+};
+
+static void dbwrap_store_fn(
+ struct db_record *rec,
+ TDB_DATA value,
+ void *private_data)
+{
+ struct dbwrap_store_state *state = private_data;
+ state->status = dbwrap_record_store(rec, state->data, state->flags);
+}
+
+NTSTATUS dbwrap_store(struct db_context *db, TDB_DATA key,
+ TDB_DATA data, int flags)
+{
+ struct dbwrap_store_state state = { .data = data, .flags = flags };
+ NTSTATUS status;
+
+ status = dbwrap_do_locked(db, key, dbwrap_store_fn, &state);
+ if (!NT_STATUS_IS_OK(status)) {
+ return status;
+ }
+
+ return state.status;
+}
+
+struct dbwrap_delete_state {
+ NTSTATUS status;
+};
+
+static void dbwrap_delete_fn(
+ struct db_record *rec,
+ TDB_DATA value,
+ void *private_data)
+{
+ struct dbwrap_delete_state *state = private_data;
+ state->status = dbwrap_record_delete(rec);
+}
+
+NTSTATUS dbwrap_delete(struct db_context *db, TDB_DATA key)
+{
+ struct dbwrap_delete_state state = { .status = NT_STATUS_NOT_FOUND };
+ NTSTATUS status;
+
+ status = dbwrap_do_locked(db, key, dbwrap_delete_fn, &state);
+ if (!NT_STATUS_IS_OK(status)) {
+ return status;
+ }
+
+ return state.status;
+}
+
+NTSTATUS dbwrap_traverse(struct db_context *db,
+ int (*f)(struct db_record*, void*),
+ void *private_data,
+ int *count)
+{
+ int ret = db->traverse(db, f, private_data);
+
+ if (ret < 0) {
+ return NT_STATUS_INTERNAL_DB_CORRUPTION;
+ }
+
+ if (count != NULL) {
+ *count = ret;
+ }
+
+ return NT_STATUS_OK;
+}
+
+NTSTATUS dbwrap_traverse_read(struct db_context *db,
+ int (*f)(struct db_record*, void*),
+ void *private_data,
+ int *count)
+{
+ int ret = db->traverse_read(db, f, private_data);
+
+ if (ret < 0) {
+ return NT_STATUS_INTERNAL_DB_CORRUPTION;
+ }
+
+ if (count != NULL) {
+ *count = ret;
+ }
+
+ return NT_STATUS_OK;
+}
+
+static void dbwrap_null_parser(TDB_DATA key, TDB_DATA val, void* data)
+{
+ return;
+}
+
+NTSTATUS dbwrap_parse_record(struct db_context *db, TDB_DATA key,
+ void (*parser)(TDB_DATA key, TDB_DATA data,
+ void *private_data),
+ void *private_data)
+{
+ if (parser == NULL) {
+ parser = dbwrap_null_parser;
+ }
+ return db->parse_record(db, key, parser, private_data);
+}
+
+struct dbwrap_parse_record_state {
+ struct db_context *db;
+ TDB_DATA key;
+ uint8_t _keybuf[64];
+};
+
+static void dbwrap_parse_record_done(struct tevent_req *subreq);
+
+struct tevent_req *dbwrap_parse_record_send(
+ TALLOC_CTX *mem_ctx,
+ struct tevent_context *ev,
+ struct db_context *db,
+ TDB_DATA key,
+ void (*parser)(TDB_DATA key, TDB_DATA data, void *private_data),
+ void *private_data,
+ enum dbwrap_req_state *req_state)
+{
+ struct tevent_req *req = NULL;
+ struct tevent_req *subreq = NULL;
+ struct dbwrap_parse_record_state *state = NULL;
+ NTSTATUS status;
+
+ req = tevent_req_create(mem_ctx, &state, struct dbwrap_parse_record_state);
+ if (req == NULL) {
+ *req_state = DBWRAP_REQ_ERROR;
+ return NULL;
+ }
+
+ *state = (struct dbwrap_parse_record_state) {
+ .db = db,
+ };
+
+ if (parser == NULL) {
+ parser = dbwrap_null_parser;
+ }
+
+ *req_state = DBWRAP_REQ_INIT;
+
+ if (db->parse_record_send == NULL) {
+ /*
+ * Backend doesn't implement async version, call sync one
+ */
+ status = db->parse_record(db, key, parser, private_data);
+ if (tevent_req_nterror(req, status)) {
+ *req_state = DBWRAP_REQ_DONE;
+ return tevent_req_post(req, ev);
+ }
+
+ *req_state = DBWRAP_REQ_DONE;
+ tevent_req_done(req);
+ return tevent_req_post(req, ev);
+ }
+
+ /*
+ * Copy the key into our state ensuring the key data buffer is always
+ * available to all the dbwrap backends over the entire lifetime of the
+ * async request. Otherwise the caller might have free'd the key buffer.
+ */
+ if (key.dsize > sizeof(state->_keybuf)) {
+ state->key.dptr = talloc_memdup(state, key.dptr, key.dsize);
+ if (tevent_req_nomem(state->key.dptr, req)) {
+ return tevent_req_post(req, ev);
+ }
+ } else {
+ memcpy(state->_keybuf, key.dptr, key.dsize);
+ state->key.dptr = state->_keybuf;
+ }
+ state->key.dsize = key.dsize;
+
+ subreq = db->parse_record_send(state,
+ ev,
+ db,
+ state->key,
+ parser,
+ private_data,
+ req_state);
+ if (tevent_req_nomem(subreq, req)) {
+ *req_state = DBWRAP_REQ_ERROR;
+ return tevent_req_post(req, ev);
+ }
+
+ tevent_req_set_callback(subreq,
+ dbwrap_parse_record_done,
+ req);
+ return req;
+}
+
+static void dbwrap_parse_record_done(struct tevent_req *subreq)
+{
+ struct tevent_req *req = tevent_req_callback_data(
+ subreq, struct tevent_req);
+ struct dbwrap_parse_record_state *state = tevent_req_data(
+ req, struct dbwrap_parse_record_state);
+ NTSTATUS status;
+
+ status = state->db->parse_record_recv(subreq);
+ TALLOC_FREE(subreq);
+ if (!NT_STATUS_IS_OK(status)) {
+ tevent_req_nterror(req, status);
+ return;
+ }
+
+ tevent_req_done(req);
+}
+
+NTSTATUS dbwrap_parse_record_recv(struct tevent_req *req)
+{
+ return tevent_req_simple_recv_ntstatus(req);
+}
+
+NTSTATUS dbwrap_do_locked(struct db_context *db, TDB_DATA key,
+ void (*fn)(struct db_record *rec,
+ TDB_DATA value,
+ void *private_data),
+ void *private_data)
+{
+ struct db_record *rec;
+
+ if (db->do_locked != NULL) {
+ NTSTATUS status;
+
+ if (db->lock_order != DBWRAP_LOCK_ORDER_NONE) {
+ dbwrap_lock_order_lock(db->name, db->lock_order);
+ }
+
+ status = db->do_locked(db, key, fn, private_data);
+
+ if (db->lock_order != DBWRAP_LOCK_ORDER_NONE) {
+ dbwrap_lock_order_unlock(db->name, db->lock_order);
+ }
+
+ return status;
+ }
+
+ rec = dbwrap_fetch_locked(db, db, key);
+ if (rec == NULL) {
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ /*
+ * Invalidate rec->value, nobody shall assume it's set from
+ * within dbwrap_do_locked().
+ */
+ rec->value_valid = false;
+
+ fn(rec, rec->value, private_data);
+
+ TALLOC_FREE(rec);
+
+ return NT_STATUS_OK;
+}
+
+int dbwrap_wipe(struct db_context *db)
+{
+ if (db->wipe == NULL) {
+ return dbwrap_fallback_wipe(db);
+ }
+ return db->wipe(db);
+}
+
+int dbwrap_check(struct db_context *db)
+{
+ if (db->check == NULL) {
+ return dbwrap_fallback_check(db);
+ }
+ return db->check(db);
+}
+
+int dbwrap_get_seqnum(struct db_context *db)
+{
+ return db->get_seqnum(db);
+}
+
+int dbwrap_transaction_start(struct db_context *db)
+{
+ if (!db->persistent) {
+ /*
+ * dbwrap_ctdb has two different data models for persistent
+ * and non-persistent databases. Transactions are supported
+ * only for the persistent databases. This check is here to
+ * prevent breakages of the cluster case, autobuild at this
+ * point only tests non-clustered Samba. Before removing this
+ * check, please make sure that this facility has also been
+ * added to dbwrap_ctdb.
+ *
+ * Thanks, vl
+ */
+ DEBUG(1, ("transactions not supported on non-persistent "
+ "database %s\n", db->name));
+ return -1;
+ }
+ return db->transaction_start(db);
+}
+
+NTSTATUS dbwrap_transaction_start_nonblock(struct db_context *db)
+{
+ if (db->transaction_start_nonblock) {
+ return db->transaction_start_nonblock(db);
+ } else {
+ return dbwrap_transaction_start(db) == 0 ? NT_STATUS_OK
+ : NT_STATUS_UNSUCCESSFUL;
+ }
+}
+
+int dbwrap_transaction_commit(struct db_context *db)
+{
+ return db->transaction_commit(db);
+}
+
+int dbwrap_transaction_cancel(struct db_context *db)
+{
+ return db->transaction_cancel(db);
+}
+
+size_t dbwrap_db_id(struct db_context *db, uint8_t *id, size_t idlen)
+{
+ return db->id(db, id, idlen);
+}
+
+bool dbwrap_is_persistent(struct db_context *db)
+{
+ return db->persistent;
+}
+
+const char *dbwrap_name(struct db_context *db)
+{
+ return db->name;
+}
+
+static ssize_t tdb_data_buf(const TDB_DATA *dbufs, int num_dbufs,
+ uint8_t *buf, size_t buflen)
+{
+ size_t needed = 0;
+ uint8_t *p = buf;
+ int i;
+
+ for (i=0; i<num_dbufs; i++) {
+ size_t thislen = dbufs[i].dsize;
+
+ needed += thislen;
+ if (needed < thislen) {
+ /* wrap */
+ return -1;
+ }
+
+ if (p != NULL && (thislen != 0) && (needed <= buflen)) {
+ memcpy(p, dbufs[i].dptr, thislen);
+ p += thislen;
+ }
+ }
+
+ return needed;
+}
+
+
+TDB_DATA dbwrap_merge_dbufs(TALLOC_CTX *mem_ctx,
+ const TDB_DATA *dbufs, int num_dbufs)
+{
+ ssize_t len = tdb_data_buf(dbufs, num_dbufs, NULL, 0);
+ uint8_t *buf;
+
+ if (len == -1) {
+ return (TDB_DATA) {0};
+ }
+
+ buf = talloc_array(mem_ctx, uint8_t, len);
+ if (buf == NULL) {
+ return (TDB_DATA) {0};
+ }
+
+ tdb_data_buf(dbufs, num_dbufs, buf, len);
+
+ return (TDB_DATA) { .dptr = buf, .dsize = len };
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-24 12:53:24 +0000