Adding upstream version 2:4.20.0+dfsg.upstream/2%4.20.0+dfsg

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 736 insertions, 0 deletions

diff --git a/lib/dbwrap/dbwrap.c b/lib/dbwrap/dbwrap.c
new file mode 100644
index 0000000..19f6c29
--- /dev/null
+++ b/lib/dbwrap/dbwrap.c
@@ -0,0 +1,736 @@
+/*
+   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;
+}
+
+struct dbwrap_merge_dbs_state {
+	struct db_context *to;
+	int flags;
+};
+
+/* Copy a single record to the db_context passed in private_data */
+static int dbwrap_merge_dbs_copy_record(struct db_record *rec,
+					    void *private_data)
+{
+	struct dbwrap_merge_dbs_state *state = private_data;
+
+	TDB_DATA data = dbwrap_record_get_value(rec);
+	TDB_DATA key = dbwrap_record_get_key(rec);
+	NTSTATUS status = dbwrap_store(state->to, key, data, state->flags);
+
+	return NT_STATUS_IS_OK(status) ? 0 : 1;
+}
+
+NTSTATUS
+dbwrap_merge_dbs(struct db_context *to, struct db_context *from, int flags)
+{
+	struct dbwrap_merge_dbs_state state = {.to = to, .flags = flags};
+
+	return dbwrap_traverse(from,
+			       dbwrap_merge_dbs_copy_record,
+			       &state,
+			       NULL);
+}
+
+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;
+}
+
+
+NTSTATUS dbwrap_merge_dbufs(TDB_DATA *buf, TALLOC_CTX *mem_ctx,
+			    const TDB_DATA *dbufs, int num_dbufs)
+{
+	ssize_t len = tdb_data_buf(dbufs, num_dbufs, NULL, 0);
+
+	if (len == -1) {
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	if (buf->dsize != len) {
+		uint8_t *tmp;
+
+		tmp = talloc_realloc(mem_ctx, buf->dptr, uint8_t, len);
+		if (tmp == NULL && len != 0) {
+			return NT_STATUS_NO_MEMORY;
+		}
+
+		buf->dptr = tmp;
+		buf->dsize = len;
+	}
+
+	tdb_data_buf(dbufs, num_dbufs, buf->dptr, buf->dsize);
+
+	return NT_STATUS_OK;
+}