An implementation of the Frame Streams data transport protocol for the Unbound DNSTAP message logging facility. More...

#include "config.h"
#include "dnstap/dtstream.h"
#include "dnstap/dnstap_fstrm.h"
#include "util/config_file.h"
#include "util/ub_event.h"
#include "util/net_help.h"
#include "services/outside_network.h"
#include "sldns/sbuffer.h"
#include <fcntl.h>

Data Structures
struct	stop_flush_info
	structure to keep track of information during stop flush More...

Macros
#define	DTIO_MESSAGES_PER_CALLBACK 100
	number of messages to process in one output callback

#define	DTIO_RECONNECT_TIMEOUT_MIN 10
	the msec to wait for reconnect (if not immediate, the first attempt)

#define	DTIO_RECONNECT_TIMEOUT_MAX 1000
	the msec to wait for reconnect max after backoff

#define	DTIO_RECONNECT_TIMEOUT_SLOW 1000
	the msec to wait for reconnect slow, to stop busy spinning on reconnect

#define	DTIO_MSG_FOR_WAKEUP 32
	number of messages before wakeup of thread

#define	DTIO_RECV_FRAME_MAX_LEN 1000
	maximum length of received frame

Enumerations
enum	{ DTIO_COMMAND_STOP = 0 , DTIO_COMMAND_WAKEUP = 1 }
	DTIO command channel commands. More...

Functions
static void	dtio_open_output (struct dt_io_thread *dtio)
	open the output channel More...

static int	dtio_add_output_event_write (struct dt_io_thread *dtio)
	add output event for read and write More...

static void	dtio_reconnect_enable (struct dt_io_thread *dtio)
	start reconnection attempts More...

static void	dtio_stop_flush_exit (struct stop_flush_info *info)
	stop from stop_flush event loop More...

static int	dtio_control_start_send (struct dt_io_thread *dtio)
	setup a start control message

struct dt_msg_queue *	dt_msg_queue_create (struct comm_base *base)
	Create new (empty) worker message queue. More...

static void	dt_msg_queue_clear (struct dt_msg_queue *mq)
	clear the message list, caller must hold the lock

void	dt_msg_queue_delete (struct dt_msg_queue *mq)
	Delete a worker message queue. More...

static void	dtio_wakeup (struct dt_io_thread *dtio)
	make the dtio wake up by sending a wakeup command

void	mq_wakeup_cb (void *arg)
	timer callback to wakeup dtio thread to process messages

static void	dt_msg_queue_start_timer (struct dt_msg_queue *mq, int wakeupnow)
	start timer to wakeup dtio because there is content in the queue

void	dt_msg_queue_submit (struct dt_msg_queue mq, void buf, size_t len)
	Submit a message to the queue. More...

struct dt_io_thread *	dt_io_thread_create (void)
	Create IO thread. More...

void	dt_io_thread_delete (struct dt_io_thread *dtio)
	Delete the IO thread structure. More...

int	dt_io_thread_apply_cfg (struct dt_io_thread dtio, struct config_file cfg)
	Apply config to the dtio thread. More...

int	dt_io_thread_register_queue (struct dt_io_thread dtio, struct dt_msg_queue mq)
	Register a msg queue to the io thread. More...

void	dt_io_thread_unregister_queue (struct dt_io_thread dtio, struct dt_msg_queue mq)
	Unregister queue from io thread. More...

static int	dt_msg_queue_pop (struct dt_msg_queue mq, void buf, size_t len)
	pick a message from the queue, the routine locks and unlocks, returns true if there is a message

static int	dtio_find_in_queue (struct dt_io_thread dtio, struct dt_msg_queue mq)
	find message in queue, false if no message, true if message to send

static int	dtio_find_msg (struct dt_io_thread *dtio)
	find a new message to write, search message queues, false if none

void	dtio_reconnect_timeout_cb (int ATTR_UNUSED(fd), short ATTR_UNUSED(bits), void *arg)
	callback for the dnstap reconnect, to start reconnecting to output

static void	dtio_reconnect_del (struct dt_io_thread *dtio)
	remove dtio reconnect timer

static void	dtio_reconnect_clear (struct dt_io_thread *dtio)
	clear the reconnect exponential backoff timer. More...

static void	dtio_reconnect_slow (struct dt_io_thread *dtio, int msec)
	reconnect slowly, because we already know we have to wait for a bit

static void	dtio_cur_msg_free (struct dt_io_thread *dtio)
	delete the current message in the dtio, and reset counters

static void	dtio_read_frame_free (struct dt_frame_read_buf *rb)
	delete the buffer and counters used to read frame

static void	dtio_del_output_event (struct dt_io_thread *dtio)
	del the output file descriptor event for listening

static void	dtio_close_fd (struct dt_io_thread *dtio)
	close dtio socket and set it to -1

static void	dtio_close_output (struct dt_io_thread *dtio)
	close and stop the output file descriptor event

static int	dtio_check_nb_connect (struct dt_io_thread *dtio)
	check for pending nonblocking connect errors, returns 1 if it is okay. More...

static int	dtio_write_buf (struct dt_io_thread dtio, uint8_t buf, size_t len)
	write buffer to output. More...

static int	dtio_write_more_of_len (struct dt_io_thread *dtio)
	write more of the length, preceding the data frame. More...

static int	dtio_write_more_of_data (struct dt_io_thread *dtio)
	write more of the data frame. More...

static int	dtio_write_more (struct dt_io_thread *dtio)
	write more of the current message. More...

static ssize_t	receive_bytes (struct dt_io_thread dtio, void buf, size_t len)
	Receive bytes from dtio->fd, store in buffer. More...

static int	dtio_check_close (struct dt_io_thread *dtio)
	check if the output fd has been closed, it returns false if the stream is closed.

static int	dtio_read_accept_frame (struct dt_io_thread *dtio)
	Read accept frame. More...

static int	dtio_add_output_event_read (struct dt_io_thread *dtio)
	add the output file descriptor event for listening, read only

static void	dtio_sleep (struct dt_io_thread *dtio)
	put the dtio thread to sleep

void	dtio_output_cb (int ATTR_UNUSED(fd), short bits, void *arg)
	callback for the dnstap events, to write to the output

void	dtio_cmd_cb (int fd, short ATTR_UNUSED(bits), void *arg)
	callback for the dnstap commandpipe, to stop the dnstap IO

static void	dtio_setup_base (struct dt_io_thread dtio, time_t secs, struct timeval *now)
	setup the event base for the dnstap io thread

static void	dtio_setup_cmd (struct dt_io_thread *dtio)
	setup the cmd event for dnstap io

static void	dtio_setup_reconnect (struct dt_io_thread *dtio)
	setup the reconnect event for dnstap io

static int	dtio_control_stop_send (struct stop_flush_info *info)
	send the stop control, return true if completed the frame.

void	dtio_stop_timer_cb (int ATTR_UNUSED(fd), short ATTR_UNUSED(bits), void *arg)

void	dtio_stop_ev_cb (int ATTR_UNUSED(fd), short bits, void *arg)

static void	dtio_control_stop_flush (struct dt_io_thread *dtio)
	flush at end, last packet and stop control

static void	dtio_desetup (struct dt_io_thread *dtio)
	perform desetup and free stuff when the dnstap io thread exits

static int	dtio_control_ready_send (struct dt_io_thread *dtio)
	setup a ready control message

static int	dtio_open_output_local (struct dt_io_thread *dtio)
	open the output file descriptor for af_local

static int	dtio_open_output_tcp (struct dt_io_thread *dtio)
	open the output file descriptor for af_inet and af_inet6

static int	dtio_setup_ssl (struct dt_io_thread *dtio)
	setup the SSL structure for new connection

static void	dtio_setup_on_base (struct dt_io_thread *dtio)
	perform the setup of the writer thread on the established event_base

static void *	dnstap_io (void *arg)
	the IO thread function for the DNSTAP IO

int	dt_io_thread_start (struct dt_io_thread dtio, void event_base_nothr, int numworkers)
	Start the io thread. More...

void	dt_io_thread_stop (struct dt_io_thread *dtio)
	Stop the io thread. More...

Variables
enum { ... }	dtio_channel_command
	DTIO command channel commands.

Detailed Description

An implementation of the Frame Streams data transport protocol for the Unbound DNSTAP message logging facility.

Enumeration Type Documentation

◆ anonymous enum

anonymous enum

DTIO command channel commands.

Enumerator
DTIO_COMMAND_STOP	DTIO command channel stop.
DTIO_COMMAND_WAKEUP	DTIO command channel wakeup.

Function Documentation

◆ dtio_open_output()

static void dtio_open_output ( struct dt_io_thread * dtio )

static

open the output channel

open the output file descriptor

References dt_io_thread::check_nb_connect, dtio_close_fd(), dtio_control_ready_send(), dtio_control_start_send(), dtio_open_output_local(), dtio_open_output_tcp(), dtio_output_cb(), dtio_reconnect_enable(), dtio_setup_ssl(), dt_io_thread::event, dt_io_thread::event_base, dt_io_thread::fd, dt_io_thread::is_bidirectional, log_err(), dt_io_thread::ssl, UB_EV_PERSIST, UB_EV_READ, UB_EV_WRITE, ub_event_free(), ub_event_new(), dt_io_thread::upstream_is_tcp, dt_io_thread::upstream_is_tls, and dt_io_thread::upstream_is_unix.

Referenced by dtio_setup_on_base().

◆ dtio_add_output_event_write()

static int dtio_add_output_event_write ( struct dt_io_thread * dtio )

static

add output event for read and write

add the output file descriptor event for listening, read and write

References dtio_close_output(), dt_io_thread::event, dt_io_thread::event_added, dt_io_thread::event_added_is_write, log_err(), UB_EV_WRITE, ub_event_add(), ub_event_add_bits(), and ub_event_del().

Referenced by dtio_setup_on_base().

◆ dtio_reconnect_enable()

static void dtio_reconnect_enable ( struct dt_io_thread * dtio )

static

start reconnection attempts

attempt to reconnect to the output, after a timeout

References dtio_reconnect_timeout_cb(), DTIO_RECONNECT_TIMEOUT_MAX, DTIO_RECONNECT_TIMEOUT_MIN, dt_io_thread::event_base, log_err(), dt_io_thread::reconnect_is_added, dt_io_thread::reconnect_timeout, dt_io_thread::reconnect_timer, ub_timer_add(), VERB_ALGO, verbose(), and dt_io_thread::want_to_exit.

Referenced by dtio_close_output(), dtio_open_output(), and dtio_reconnect_slow().

◆ dtio_stop_flush_exit()

static void dtio_stop_flush_exit ( struct stop_flush_info * info )

static

stop from stop_flush event loop

exit the stop flush base

References stop_flush_info::base, log_err(), ub_event_base_loopexit(), and stop_flush_info::want_to_exit_flush.

Referenced by dtio_control_stop_send().

◆ dt_msg_queue_create()

struct dt_msg_queue* dt_msg_queue_create ( struct comm_base * base )

Create new (empty) worker message queue.

Limit set to default on max.

Parameters

base	event base for wakeup timer.

Returns: NULL on malloc failure or a new queue (not locked).

References comm_timer_create(), dt_msg_queue::lock, dt_msg_queue::maxsize, mq_wakeup_cb(), and dt_msg_queue::wakeup_timer.

◆ dt_msg_queue_delete()

void dt_msg_queue_delete ( struct dt_msg_queue * mq )

Delete a worker message queue.

It has to be unlinked from access, so it can be deleted without lock worries. The queue is emptied (deleted).

Parameters

mq	message queue.

References comm_timer_delete(), dt_msg_queue_clear(), dt_msg_queue::lock, and dt_msg_queue::wakeup_timer.

◆ dt_msg_queue_submit()

void dt_msg_queue_submit	(	struct dt_msg_queue *	mq,
		void *	buf,
		size_t	len
	)

Submit a message to the queue.

The queue is locked by the routine, the message is inserted, and then the queue is unlocked so the message can be picked up by the writer thread.

Parameters

mq	message queue.
buf	buffer with message (dnstap contents). The buffer must have been malloced by caller. It is linked in the queue, and is free()d after use. If the routine fails the buffer is freed as well (and nothing happens, the item could not be logged).
len	length of buffer.

References dt_msg_entry::buf, dt_msg_queue::cursize, dt_msg_queue_start_timer(), DTIO_MSG_FOR_WAKEUP, dt_msg_queue::first, dt_msg_entry::len, dt_msg_queue::lock, log_err(), dt_msg_queue::maxsize, dt_msg_queue::msgcount, dt_msg_entry::next, and entry::next.

◆ dt_io_thread_create()

struct dt_io_thread* dt_io_thread_create ( void )

Create IO thread.

Returns: new io thread object. not yet started. or NULL malloc failure.

References dt_io_thread::wakeup_timer_enabled, and dt_io_thread::wakeup_timer_lock.

◆ dt_io_thread_delete()

void dt_io_thread_delete ( struct dt_io_thread * dtio )

Delete the IO thread structure.

Parameters

dtio	the io thread that is deleted. It must not be running.

References dt_io_thread::client_cert_file, dt_io_thread::client_key_file, dt_io_thread::io_list, dt_io_thread::ip_str, dt_io_list_item::next, dt_io_thread::socket_path, dt_io_thread::ssl_ctx, dt_io_thread::tls_server_name, and dt_io_thread::wakeup_timer_lock.

◆ dt_io_thread_apply_cfg()

int dt_io_thread_apply_cfg	(	struct dt_io_thread *	dtio,
		struct config_file *	cfg
	)

Apply config to the dtio thread.

Parameters

dtio	io thread, not yet started.
cfg	config file struct.

Returns: false on malloc failure.

References check_auth_name_for_ssl(), config_file::chrootdir, dt_io_thread::client_cert_file, dt_io_thread::client_key_file, connect_sslctx_create(), config_file::dnstap, config_file::dnstap_bidirectional, config_file::dnstap_ip, config_file::dnstap_socket_path, config_file::dnstap_tls, config_file::dnstap_tls_cert_bundle, config_file::dnstap_tls_client_cert_file, config_file::dnstap_tls_client_key_file, config_file::dnstap_tls_server_name, dt_io_thread::ip_str, dt_io_thread::is_bidirectional, log_err(), log_warn(), dt_io_thread::socket_path, dt_io_thread::ssl_ctx, config_file::tls_cert_bundle, dt_io_thread::tls_server_name, dt_io_thread::tls_use_sni, config_file::tls_use_sni, config_file::tls_win_cert, dt_io_thread::upstream_is_tcp, dt_io_thread::upstream_is_tls, dt_io_thread::upstream_is_unix, and dt_io_thread::use_client_certs.

◆ dt_io_thread_register_queue()

int dt_io_thread_register_queue	(	struct dt_io_thread *	dtio,
		struct dt_msg_queue *	mq
	)

Register a msg queue to the io thread.

It will be polled to see if there are messages and those then get removed and sent, when the thread is running.

Parameters

dtio	the io thread.
mq	message queue to register.

Returns: false on failure (malloc failure).

References dt_msg_queue::dtio, dt_io_thread::io_list, dt_io_thread::io_list_iter, dt_msg_queue::lock, dt_io_list_item::next, and dt_io_list_item::queue.

◆ dt_io_thread_unregister_queue()

void dt_io_thread_unregister_queue	(	struct dt_io_thread *	dtio,
		struct dt_msg_queue *	mq
	)

Unregister queue from io thread.

Parameters

dtio	the io thread.
mq	message queue.

References dt_msg_queue::dtio, dt_io_thread::io_list, dt_io_thread::io_list_iter, dt_msg_queue::lock, dt_io_list_item::next, and dt_io_list_item::queue.

◆ dtio_reconnect_clear()

static void dtio_reconnect_clear ( struct dt_io_thread * dtio )

static

clear the reconnect exponential backoff timer.

We have successfully connected so we can try again with short timeouts.

References dtio_reconnect_del(), and dt_io_thread::reconnect_timeout.

Referenced by dtio_check_nb_connect(), and dtio_setup_reconnect().

◆ dtio_check_nb_connect()

static int dtio_check_nb_connect ( struct dt_io_thread * dtio )

static

check for pending nonblocking connect errors, returns 1 if it is okay.

-1 on error (close it), 0 to try later

References dt_io_thread::check_nb_connect, dtio_reconnect_clear(), error(), dt_io_thread::event, dt_io_thread::fd, dt_io_thread::ip_str, log_err(), sock_strerror(), dt_io_thread::socket_path, dt_io_thread::stop_flush_event, UB_EV_WRITE, ub_winsock_tcp_wouldblock(), VERB_DETAIL, and verbose().

◆ dtio_write_buf()

static int dtio_write_buf	(	struct dt_io_thread *	dtio,
		uint8_t *	buf,
		size_t	len
	)

static

write buffer to output.

returns number of bytes written, 0 if nothing happened, try again later, or -1 if the channel is to be closed.

References dt_io_thread::event, dt_io_thread::fd, log_err(), sock_strerror(), dt_io_thread::ssl, dt_io_thread::stop_flush_event, UB_EV_WRITE, and ub_winsock_tcp_wouldblock().

Referenced by dtio_control_stop_send(), dtio_write_more_of_data(), and dtio_write_more_of_len().

◆ dtio_write_more_of_len()

static int dtio_write_more_of_len ( struct dt_io_thread * dtio )

static

write more of the length, preceding the data frame.

return true if message is done, false if incomplete.

References dt_io_thread::cur_msg_len, dt_io_thread::cur_msg_len_done, dtio_close_output(), dtio_del_output_event(), dtio_write_buf(), and dt_io_thread::ssl.

Referenced by dtio_write_more().

◆ dtio_write_more_of_data()

static int dtio_write_more_of_data ( struct dt_io_thread * dtio )

static

write more of the data frame.

return true if message is done, false if incomplete.

References dt_io_thread::cur_msg, dt_io_thread::cur_msg_done, dt_io_thread::cur_msg_len, dtio_close_output(), dtio_del_output_event(), and dtio_write_buf().

Referenced by dtio_write_more().

◆ dtio_write_more()

static int dtio_write_more ( struct dt_io_thread * dtio )

static

write more of the current message.

false if incomplete, true if the message is done

References dt_io_thread::cur_msg_done, dt_io_thread::cur_msg_len, dt_io_thread::cur_msg_len_done, dtio_write_more_of_data(), and dtio_write_more_of_len().

◆ receive_bytes()

static ssize_t receive_bytes	(	struct dt_io_thread *	dtio,
		void *	buf,
		size_t	len
	)

static

Receive bytes from dtio->fd, store in buffer.

Returns 0: closed, -1: continue, >0: number of bytes read into buffer

References DTIO_RECONNECT_TIMEOUT_MIN, dt_io_thread::event, dt_io_thread::fd, dt_io_thread::ip_str, log_err(), MSG_DONTWAIT, dt_io_thread::reconnect_timeout, dt_io_thread::socket_path, dt_io_thread::stop_flush_event, UB_EV_READ, ub_winsock_tcp_wouldblock(), VERB_DETAIL, verbose(), and verbosity.

Referenced by dtio_check_close(), and dtio_read_accept_frame().

◆ dtio_read_accept_frame()

static int dtio_read_accept_frame ( struct dt_io_thread * dtio )

static

Read accept frame.

Returns -1: continue reading, 0: closed, 1: valid accept received.

References dt_frame_read_buf::buf, dt_frame_read_buf::buf_cap, dt_frame_read_buf::buf_count, dt_frame_read_buf::control_frame, DTIO_RECV_FRAME_MAX_LEN, dt_frame_read_buf::frame_len, dt_frame_read_buf::frame_len_done, log_err(), dt_io_thread::read_frame, receive_bytes(), dt_io_thread::ssl, VERB_OPS, and verbose().

◆ dt_io_thread_start()

int dt_io_thread_start	(	struct dt_io_thread *	dtio,
		void *	event_base_nothr,
		int	numworkers
	)

Start the io thread.

Parameters

dtio	the io thread.
event_base_nothr	the event base to attach the events to, in case we are running without threads. With threads, this is ignored and a thread is started to process the dnstap log messages.
numworkers	number of worker threads. The dnstap io thread is that number +1 as the threadnumber (in logs).

Returns: false on failure.

References dt_io_thread::commandpipe, dnstap_io(), dtio_setup_on_base(), dt_io_thread::event_base, log_err(), dt_io_thread::started, dt_io_thread::threadnum, and dt_io_thread::tid.

◆ dt_io_thread_stop()

void dt_io_thread_stop ( struct dt_io_thread * dtio )

Stop the io thread.

Parameters

dtio	the io thread.

References dt_io_thread::commandpipe, DTIO_COMMAND_STOP, dtio_desetup(), log_err(), sock_strerror(), dt_io_thread::started, dt_io_thread::tid, VERB_ALGO, verbose(), and dt_io_thread::want_to_exit.

Referenced by worker_delete().

Data Structures

Macros

Enumerations

Functions

Variables

Detailed Description

Enumeration Type Documentation

◆ anonymous enum

Function Documentation

◆ dtio_open_output()

◆ dtio_add_output_event_write()

◆ dtio_reconnect_enable()

◆ dtio_stop_flush_exit()

◆ dt_msg_queue_create()

◆ dt_msg_queue_delete()

◆ dt_msg_queue_submit()

◆ dt_io_thread_create()

◆ dt_io_thread_delete()

◆ dt_io_thread_apply_cfg()

◆ dt_io_thread_register_queue()

◆ dt_io_thread_unregister_queue()

◆ dtio_reconnect_clear()

◆ dtio_check_nb_connect()

◆ dtio_write_buf()

◆ dtio_write_more_of_len()

◆ dtio_write_more_of_data()

◆ dtio_write_more()

◆ receive_bytes()

◆ dtio_read_accept_frame()

◆ dt_io_thread_start()

◆ dt_io_thread_stop()