onion_queue.c File Reference

Functions to queue create cells for processing. More...

#include "core/or/or.h"
#include "feature/relay/onion_queue.h"
#include "app/config/config.h"
#include "core/mainloop/cpuworker.h"
#include "core/or/circuitlist.h"
#include "core/or/onion.h"
#include "feature/nodelist/networkstatus.h"
#include "feature/stats/rephist.h"
#include "core/or/or_circuit_st.h"

Go to the source code of this file.

Data Structures
struct	onion_queue_t

Macros
#define	ONIONQUEUE_WAIT_CUTOFF   5
#define	WARN_TOO_MANY_CIRC_CREATIONS_INTERVAL   (60)
#define	DEFAULT_NUM_NTORS_PER_TAP   10
#define	MIN_NUM_NTORS_PER_TAP   1
#define	MAX_NUM_NTORS_PER_TAP   100000

Typedefs
typedef struct onion_queue_head_t	onion_queue_head_t

Functions
	TOR_TAILQ_HEAD (onion_queue_head_t, onion_queue_t)
static int	num_ntors_per_tap (void)
static void	onion_queue_entry_remove (onion_queue_t *victim)
static int	have_room_for_onionskin (uint16_t type)
int	onion_pending_add (or_circuit_t *circ, create_cell_t *onionskin)
static uint16_t	decide_next_handshake_type (void)
or_circuit_t *	onion_next_task (create_cell_t **onionskin_out)
int	onion_num_pending (uint16_t handshake_type)
void	onion_pending_remove (or_circuit_t *circ)
void	clear_pending_onions (void)

Variables
static onion_queue_head_t	ol_list [MAX_ONION_HANDSHAKE_TYPE+1]
static int	ol_entries [MAX_ONION_HANDSHAKE_TYPE+1]

Detailed Description

Functions to queue create cells for processing.

Relays invoke these functions when they receive a CREATE or EXTEND cell in command.c or relay.c, in order to queue the pending request. They also invoke them from cpuworker.c, which handles dispatching onionskin requests to different worker threads.

This module also handles:

• Queueing incoming onionskins on the relay side before passing them to worker threads.
• Expiring onionskins on the relay side if they have waited for too long.

Definition in file onion_queue.c.

Macro Definition Documentation

ONIONQUEUE_WAIT_CUTOFF

#define ONIONQUEUE_WAIT_CUTOFF   5

5 seconds on the onion queue til we just send back a destroy

Definition at line 51 of file onion_queue.c.

Function Documentation

clear_pending_onions()

void clear_pending_onions

(

void

)

Remove all circuits from the pending list. Called from tor_free_all.

Definition at line 359 of file onion_queue.c.

decide_next_handshake_type()

static uint16_t decide_next_handshake_type ( void  )

static

Choose which onion queue we'll pull from next. If one is empty choose the other; if they both have elements, load balance across them but favoring NTOR.

Definition at line 235 of file onion_queue.c.

Referenced by onion_next_task().

have_room_for_onionskin()

static int have_room_for_onionskin ( uint16_t  type )

static

Return true iff we have room to queue another onionskin of type type.

Definition at line 80 of file onion_queue.c.

num_ntors_per_tap()

static int num_ntors_per_tap ( void  )

static

Return a fairness parameter, to prefer processing NTOR style handshakes but still slowly drain the TAP queue so we don't starve it entirely.

Definition at line 217 of file onion_queue.c.

onion_next_task()

or_circuit_t* onion_next_task

(

create_cell_t **

onionskin_out

)

Remove the highest priority item from ol_list[] and return it, or return NULL if the lists are empty.

Definition at line 275 of file onion_queue.c.

onion_num_pending()

int onion_num_pending

(

uint16_t

handshake_type

)

Return the number of handshake_type-style create requests pending.

Definition at line 307 of file onion_queue.c.

onion_pending_add()

int onion_pending_add	(	or_circuit_t *	circ,
		create_cell_t *	onionskin
	)

Add circ to the end of ol_list and return 0, except if ol_list is too long, in which case do nothing and return -1.

Definition at line 143 of file onion_queue.c.

onion_pending_remove()

void onion_pending_remove

(

or_circuit_t *

circ

)

Go through ol_list, find the onion_queue_t element which points to circ, remove and free that element. Leave circ itself alone.

Definition at line 316 of file onion_queue.c.

Referenced by circuit_about_to_free().

onion_queue_entry_remove()

static void onion_queue_entry_remove ( onion_queue_t *  victim )

static

Remove a queue entry victim from the queue, unlinking it from its circuit and freeing it and any structures it owns.

Definition at line 333 of file onion_queue.c.

Referenced by onion_pending_remove().

Variable Documentation

ol_entries

int ol_entries[MAX_ONION_HANDSHAKE_TYPE+1]

static

Number of entries of each type currently in each element of ol_list[].

Definition at line 65 of file onion_queue.c.

Referenced by decide_next_handshake_type(), and onion_num_pending().

ol_list

onion_queue_head_t ol_list[MAX_ONION_HANDSHAKE_TYPE+1]

static

Initial value:

=
{ TOR_TAILQ_HEAD_INITIALIZER(ol_list[0]), 
  TOR_TAILQ_HEAD_INITIALIZER(ol_list[1]), 
  TOR_TAILQ_HEAD_INITIALIZER(ol_list[2]), 
}

Array of queues of circuits waiting for CPU workers. An element is NULL if that queue is empty.

Definition at line 58 of file onion_queue.c.

Referenced by onion_next_task().