Ejemplo n.º 1
0
static NTSTATUS smbXsrv_open_global_lookup(struct smbXsrv_open_table *table,
        uint32_t open_global_id,
        TALLOC_CTX *mem_ctx,
        struct smbXsrv_open_global0 **_global)
{
    TDB_DATA key;
    uint8_t key_buf[SMBXSRV_OPEN_GLOBAL_TDB_KEY_SIZE];
    struct db_record *global_rec = NULL;
    bool is_free = false;

    *_global = NULL;

    if (table->global.db_ctx == NULL) {
        return NT_STATUS_INTERNAL_ERROR;
    }

    key = smbXsrv_open_global_id_to_key(open_global_id, key_buf);

    global_rec = dbwrap_fetch_locked(table->global.db_ctx, mem_ctx, key);
    if (global_rec == NULL) {
        DEBUG(0, ("smbXsrv_open_global_lookup(0x%08x): "
                  "Failed to lock global key '%s'\n",
                  open_global_id,
                  hex_encode_talloc(talloc_tos(), key.dptr,
                                    key.dsize)));
        return NT_STATUS_INTERNAL_DB_ERROR;
    }

    smbXsrv_open_global_verify_record(global_rec,
                                      &is_free,
                                      NULL,
                                      mem_ctx,
                                      _global);
    if (is_free) {
        talloc_free(global_rec);
        return NT_STATUS_OBJECT_NAME_NOT_FOUND;
    }

    (*_global)->db_rec = talloc_move(*_global, &global_rec);

    talloc_set_destructor(*_global, smbXsrv_open_global_destructor);

    return NT_STATUS_OK;
}
Ejemplo n.º 2
0
static NTSTATUS smbXsrv_open_global_lookup(struct smbXsrv_open_table *table,
					   uint32_t open_global_id,
					   TALLOC_CTX *mem_ctx,
					   struct smbXsrv_open_global0 **_global)
{
	struct db_record *global_rec = NULL;
	bool is_free = false;

	*_global = NULL;

	if (table->global.db_ctx == NULL) {
		return NT_STATUS_INTERNAL_ERROR;
	}

	global_rec = smbXsrv_open_global_fetch_locked(table->global.db_ctx,
						      open_global_id,
						      mem_ctx);
	if (global_rec == NULL) {
		return NT_STATUS_INTERNAL_DB_ERROR;
	}

	smbXsrv_open_global_verify_record(global_rec,
					  &is_free,
					  NULL,
					  mem_ctx,
					  _global);
	if (is_free) {
		DEBUG(10, ("%s: is_free=true\n", __func__));
		talloc_free(global_rec);
		return NT_STATUS_OBJECT_NAME_NOT_FOUND;
	}

	(*_global)->db_rec = talloc_move(*_global, &global_rec);

	talloc_set_destructor(*_global, smbXsrv_open_global_destructor);

	return NT_STATUS_OK;
}
Ejemplo n.º 3
0
static NTSTATUS smbXsrv_open_local_allocate_id(struct db_context *db,
					       uint32_t lowest_id,
					       uint32_t highest_id,
					       TALLOC_CTX *mem_ctx,
					       struct db_record **_rec,
					       uint32_t *_id)
{
	struct smbXsrv_open_local_allocate_state state = {
		.lowest_id = lowest_id,
		.highest_id = highest_id,
		.last_id = 0,
		.useable_id = lowest_id,
		.status = NT_STATUS_INTERNAL_ERROR,
	};
	uint32_t i;
	uint32_t range;
	NTSTATUS status;
	int count = 0;

	*_rec = NULL;
	*_id = 0;

	if (lowest_id > highest_id) {
		return NT_STATUS_INSUFFICIENT_RESOURCES;
	}

	/*
	 * first we try randomly
	 */
	range = (highest_id - lowest_id) + 1;

	for (i = 0; i < (range / 2); i++) {
		uint32_t id;
		TDB_DATA val;
		struct db_record *rec = NULL;

		id = generate_random() % range;
		id += lowest_id;

		if (id < lowest_id) {
			id = lowest_id;
		}
		if (id > highest_id) {
			id = highest_id;
		}

		rec = smbXsrv_open_local_fetch_locked(db, id, mem_ctx);
		if (rec == NULL) {
			return NT_STATUS_INSUFFICIENT_RESOURCES;
		}

		val = dbwrap_record_get_value(rec);
		if (val.dsize != 0) {
			TALLOC_FREE(rec);
			continue;
		}

		*_rec = rec;
		*_id = id;
		return NT_STATUS_OK;
	}

	/*
	 * if the range is almost full,
	 * we traverse the whole table
	 * (this relies on sorted behavior of dbwrap_rbt)
	 */
	status = dbwrap_traverse_read(db, smbXsrv_open_local_allocate_traverse,
				      &state, &count);
	if (NT_STATUS_IS_OK(status)) {
		if (NT_STATUS_IS_OK(state.status)) {
			return NT_STATUS_INTERNAL_ERROR;
		}

		if (!NT_STATUS_EQUAL(state.status, NT_STATUS_INTERNAL_ERROR)) {
			return state.status;
		}

		if (state.useable_id <= state.highest_id) {
			state.status = NT_STATUS_OK;
		} else {
			return NT_STATUS_INSUFFICIENT_RESOURCES;
		}
	} else if (!NT_STATUS_EQUAL(status, NT_STATUS_INTERNAL_DB_CORRUPTION)) {
		/*
		 * Here we really expect NT_STATUS_INTERNAL_DB_CORRUPTION!
		 *
		 * If we get anything else it is an error, because it
		 * means we did not manage to find a free slot in
		 * the db.
		 */
		return NT_STATUS_INSUFFICIENT_RESOURCES;
	}

	if (NT_STATUS_IS_OK(state.status)) {
		uint32_t id;
		TDB_DATA val;
		struct db_record *rec = NULL;

		id = state.useable_id;

		rec = smbXsrv_open_local_fetch_locked(db, id, mem_ctx);
		if (rec == NULL) {
			return NT_STATUS_INSUFFICIENT_RESOURCES;
		}

		val = dbwrap_record_get_value(rec);
		if (val.dsize != 0) {
			TALLOC_FREE(rec);
			return NT_STATUS_INTERNAL_DB_CORRUPTION;
		}

		*_rec = rec;
		*_id = id;
		return NT_STATUS_OK;
	}

	return state.status;
}

struct smbXsrv_open_local_fetch_state {
	struct smbXsrv_open *op;
	NTSTATUS status;
};

static void smbXsrv_open_local_fetch_parser(TDB_DATA key, TDB_DATA data,
					    void *private_data)
{
	struct smbXsrv_open_local_fetch_state *state =
		(struct smbXsrv_open_local_fetch_state *)private_data;
	void *ptr;

	if (data.dsize != sizeof(ptr)) {
		state->status = NT_STATUS_INTERNAL_DB_ERROR;
		return;
	}

	memcpy(&ptr, data.dptr, data.dsize);
	state->op = talloc_get_type_abort(ptr, struct smbXsrv_open);
	state->status = NT_STATUS_OK;
}

static NTSTATUS smbXsrv_open_local_lookup(struct smbXsrv_open_table *table,
					  uint32_t open_local_id,
					  uint32_t open_global_id,
					  NTTIME now,
					  struct smbXsrv_open **_open)
{
	struct smbXsrv_open_local_fetch_state state = {
		.op = NULL,
		.status = NT_STATUS_INTERNAL_ERROR,
	};
	uint8_t key_buf[SMBXSRV_OPEN_LOCAL_TDB_KEY_SIZE];
	TDB_DATA key;
	NTSTATUS status;

	*_open = NULL;

	if (open_local_id == 0) {
		return NT_STATUS_FILE_CLOSED;
	}

	if (table == NULL) {
		/* this might happen before the end of negprot */
		return NT_STATUS_FILE_CLOSED;
	}

	if (table->local.db_ctx == NULL) {
		return NT_STATUS_INTERNAL_ERROR;
	}

	key = smbXsrv_open_local_id_to_key(open_local_id, key_buf);

	status = dbwrap_parse_record(table->local.db_ctx, key,
				     smbXsrv_open_local_fetch_parser,
				     &state);
	if (NT_STATUS_EQUAL(status, NT_STATUS_NOT_FOUND)) {
		return NT_STATUS_FILE_CLOSED;
	}
	if (!NT_STATUS_IS_OK(status)) {
		return status;
	}
	if (!NT_STATUS_IS_OK(state.status)) {
		return state.status;
	}

	if (NT_STATUS_EQUAL(state.op->status, NT_STATUS_FILE_CLOSED)) {
		return NT_STATUS_FILE_CLOSED;
	}

	if (open_global_id == 0) {
		/* make the global check a no-op for SMB1 */
		open_global_id = state.op->global->open_global_id;
	}

	if (state.op->global->open_global_id != open_global_id) {
		return NT_STATUS_FILE_CLOSED;
	}

	if (now != 0) {
		state.op->idle_time = now;
	}

	*_open = state.op;
	return state.op->status;
}

static int smbXsrv_open_global_destructor(struct smbXsrv_open_global0 *global)
{
	return 0;
}

static void smbXsrv_open_global_verify_record(struct db_record *db_rec,
					bool *is_free,
					bool *was_free,
					TALLOC_CTX *mem_ctx,
					struct smbXsrv_open_global0 **_g);

static NTSTATUS smbXsrv_open_global_allocate(struct db_context *db,
					TALLOC_CTX *mem_ctx,
					struct smbXsrv_open_global0 **_global)
{
	uint32_t i;
	struct smbXsrv_open_global0 *global = NULL;
	uint32_t last_free = 0;
	const uint32_t min_tries = 3;

	*_global = NULL;

	global = talloc_zero(mem_ctx, struct smbXsrv_open_global0);
	if (global == NULL) {
		return NT_STATUS_NO_MEMORY;
	}
	talloc_set_destructor(global, smbXsrv_open_global_destructor);

	/*
	 * Here we just randomly try the whole 32-bit space
	 *
	 * We use just 32-bit, because we want to reuse the
	 * ID for SRVSVC.
	 */
	for (i = 0; i < UINT32_MAX; i++) {
		bool is_free = false;
		bool was_free = false;
		uint32_t id;

		if (i >= min_tries && last_free != 0) {
			id = last_free;
		} else {
			id = generate_random();
		}
		if (id == 0) {
			id++;
		}
		if (id == UINT32_MAX) {
			id--;
		}

		global->db_rec = smbXsrv_open_global_fetch_locked(db, id, mem_ctx);
		if (global->db_rec == NULL) {
			talloc_free(global);
			return NT_STATUS_INSUFFICIENT_RESOURCES;
		}

		smbXsrv_open_global_verify_record(global->db_rec,
						  &is_free,
						  &was_free,
						  NULL, NULL);

		if (!is_free) {
			TALLOC_FREE(global->db_rec);
			continue;
		}

		if (!was_free && i < min_tries) {
			/*
			 * The session_id is free now,
			 * but was not free before.
			 *
			 * This happens if a smbd crashed
			 * and did not cleanup the record.
			 *
			 * If this is one of our first tries,
			 * then we try to find a real free one.
			 */
			if (last_free == 0) {
				last_free = id;
			}
			TALLOC_FREE(global->db_rec);
			continue;
		}

		global->open_global_id = id;

		*_global = global;
		return NT_STATUS_OK;
	}

	/* should not be reached */
	talloc_free(global);
	return NT_STATUS_INTERNAL_ERROR;
}