Header file for channel.c. More...

#include "core/or/or.h"
#include "core/or/circuitmux.h"
#include "lib/container/handles.h"
#include "lib/crypt_ops/crypto_ed25519.h"
#include "ext/ht.h"
#include "tor_queue.h"

Data Structures
struct	channel_t

struct	channel_listener_t

Macros
#define	tor_timer_t timeout

#define	circ_id_type_bitfield_t ENUM_BF(circ_id_type_t)

#define	CHANNEL_IS_CLOSED(chan)

#define	CHANNEL_IS_OPENING(chan)

#define	CHANNEL_IS_OPEN(chan)

#define	CHANNEL_IS_MAINT(chan)

#define	CHANNEL_IS_CLOSING(chan)

#define	CHANNEL_IS_ERROR(chan)

#define	CHANNEL_FINISHED(chan)

#define	CHANNEL_CONDEMNED(chan)

#define	CHANNEL_CAN_HANDLE_CELLS(chan)

#define	channel_handle_free(h) FREE_AND_NULL(channel_handle_t, channel_handle_free_, (h))

Typedefs
typedef void(*	channel_listener_fn_ptr) (channel_listener_t , channel_t )

typedef void(*	channel_cell_handler_fn_ptr) (channel_t , cell_t )

Enumerations
enum	channel_usage_info_t { CHANNEL_USED_NOT_USED_FOR_FULL_CIRCS = 0 , CHANNEL_USED_FOR_FULL_CIRCS , CHANNEL_USED_FOR_USER_TRAFFIC }

enum	circ_id_type_t { CIRC_ID_TYPE_LOWER =0 , CIRC_ID_TYPE_HIGHER =1 , CIRC_ID_TYPE_NEITHER =2 }

enum	channel_state_t { CHANNEL_STATE_CLOSED = 0 , CHANNEL_STATE_OPENING , CHANNEL_STATE_OPEN , CHANNEL_STATE_MAINT , CHANNEL_STATE_CLOSING , CHANNEL_STATE_ERROR , CHANNEL_STATE_LAST }

enum	channel_listener_state_t { CHANNEL_LISTENER_STATE_CLOSED = 0 , CHANNEL_LISTENER_STATE_LISTENING , CHANNEL_LISTENER_STATE_CLOSING , CHANNEL_LISTENER_STATE_ERROR , CHANNEL_LISTENER_STATE_LAST }

Functions
int	channel_state_is_valid (channel_state_t state)

int	channel_listener_state_is_valid (channel_listener_state_t state)

int	channel_state_can_transition (channel_state_t from, channel_state_t to)

int	channel_listener_state_can_transition (channel_listener_state_t from, channel_listener_state_t to)

const char *	channel_state_to_string (channel_state_t state)

const char *	channel_listener_state_to_string (channel_listener_state_t state)

void	channel_mark_for_close (channel_t *chan)

int	channel_write_packed_cell (channel_t chan, packed_cell_t cell)

void	channel_listener_mark_for_close (channel_listener_t *chan_l)

void	channel_mark_as_used_for_origin_circuit (channel_t *chan)

void	channel_listener_set_listener_fn (channel_listener_t *chan, channel_listener_fn_ptr listener)

channel_cell_handler_fn_ptr	channel_get_cell_handler (channel_t *chan)

void	channel_set_cell_handlers (channel_t *chan, channel_cell_handler_fn_ptr cell_handler)

void	channel_run_cleanup (void)

void	channel_listener_run_cleanup (void)

void	channel_free_all (void)

void	channel_dumpstats (int severity)

void	channel_listener_dumpstats (int severity)

int	channel_send_destroy (circid_t circ_id, channel_t *chan, int reason)

channel_t *	channel_connect (const tor_addr_t addr, uint16_t port, const char rsa_id_digest, const struct ed25519_public_key_t *ed_id)

channel_t *	channel_get_for_extend (const char rsa_id_digest, const struct ed25519_public_key_t ed_id, const tor_addr_t target_ipv4_addr, const tor_addr_t target_ipv6_addr, bool for_origin_circ, const char *msg_out, int launch_out)

int	channel_is_better (channel_t a, channel_t b)

channel_t *	channel_find_by_global_id (uint64_t global_identifier)

channel_t *	channel_find_by_remote_identity (const char rsa_id_digest, const struct ed25519_public_key_t ed_id)

channel_t *	channel_next_with_rsa_identity (channel_t *chan)

static int	channel_is_in_state (channel_t *chan, channel_state_t state)

const char *	channel_describe_transport (channel_t *chan)

void	channel_dump_statistics (channel_t *chan, int severity)

void	channel_dump_transport_statistics (channel_t *chan, int severity)

int	channel_get_addr_if_possible (const channel_t chan, tor_addr_t addr_out)

const char *	channel_describe_peer (channel_t *chan)

int	channel_has_queued_writes (channel_t *chan)

int	channel_is_bad_for_new_circs (channel_t *chan)

void	channel_mark_bad_for_new_circs (channel_t *chan)

int	channel_is_canonical (channel_t *chan)

int	channel_is_client (const channel_t *chan)

int	channel_is_local (channel_t *chan)

int	channel_is_incoming (channel_t *chan)

int	channel_is_outgoing (channel_t *chan)

void	channel_mark_client (channel_t *chan)

void	channel_clear_client (channel_t *chan)

int	channel_matches_extend_info (channel_t chan, extend_info_t extend_info)

int	channel_remote_identity_matches (const channel_t chan, const char rsa_id_digest, const ed25519_public_key_t *ed_id)

unsigned int	channel_num_circuits (channel_t *chan)

void	channel_set_circid_type (channel_t chan, crypto_pk_t identity_rcvd, int consider_identity)

void	channel_timestamp_client (channel_t *chan)

const char *	channel_listener_describe_transport (channel_listener_t *chan_l)

void	channel_listener_dump_statistics (channel_listener_t *chan_l, int severity)

void	channel_listener_dump_transport_statistics (channel_listener_t *chan_l, int severity)

void	channel_check_for_duplicates (void)

void	channel_update_bad_for_new_circs (const char *digest, int force)

int	channel_num_cells_writeable (channel_t *chan)

time_t	channel_when_created (channel_t *chan)

time_t	channel_when_last_client (channel_t *chan)

time_t	channel_when_last_xmit (channel_t *chan)

int	packed_cell_is_destroy (channel_t chan, const packed_cell_t packed_cell, circid_t *circid_out)

Detailed Description

Header file for channel.c.

Definition in file channel.h.

Macro Definition Documentation

◆ CHANNEL_CAN_HANDLE_CELLS

#define CHANNEL_CAN_HANDLE_CELLS ( chan )

Value:

                                        (CHANNEL_IS_OPENING(chan) || \
                                        CHANNEL_IS_OPEN(chan) || \
                                        CHANNEL_IS_MAINT(chan))

Definition at line 707 of file channel.h.

◆ CHANNEL_CONDEMNED

#define CHANNEL_CONDEMNED ( chan )

Value:

(CHANNEL_IS_CLOSING(chan) || \

CHANNEL_FINISHED(chan))

Definition at line 704 of file channel.h.

◆ CHANNEL_FINISHED

#define CHANNEL_FINISHED ( chan )

Value:

(CHANNEL_IS_CLOSED(chan) || \

CHANNEL_IS_ERROR(chan))

Definition at line 701 of file channel.h.

◆ CHANNEL_IS_CLOSED

#define CHANNEL_IS_CLOSED ( chan )

Value:

(channel_is_in_state((chan), \

CHANNEL_STATE_CLOSED))

CHANNEL_STATE_CLOSED

@ CHANNEL_STATE_CLOSED

Definition: channel.h:59

Definition at line 688 of file channel.h.

◆ CHANNEL_IS_CLOSING

#define CHANNEL_IS_CLOSING ( chan )

Value:

(channel_is_in_state((chan), \

CHANNEL_STATE_CLOSING))

CHANNEL_STATE_CLOSING

@ CHANNEL_STATE_CLOSING

Definition: channel.h:105

Definition at line 696 of file channel.h.

◆ CHANNEL_IS_ERROR

#define CHANNEL_IS_ERROR ( chan )

Value:

(channel_is_in_state((chan), \

CHANNEL_STATE_ERROR))

CHANNEL_STATE_ERROR

@ CHANNEL_STATE_ERROR

Definition: channel.h:117

Definition at line 698 of file channel.h.

◆ CHANNEL_IS_MAINT

#define CHANNEL_IS_MAINT ( chan )

Value:

(channel_is_in_state((chan), \

CHANNEL_STATE_MAINT))

CHANNEL_STATE_MAINT

@ CHANNEL_STATE_MAINT

Definition: channel.h:94

Definition at line 694 of file channel.h.

◆ CHANNEL_IS_OPEN

#define CHANNEL_IS_OPEN ( chan )

Value:

(channel_is_in_state((chan), \

CHANNEL_STATE_OPEN))

CHANNEL_STATE_OPEN

@ CHANNEL_STATE_OPEN

Definition: channel.h:82

Definition at line 692 of file channel.h.

◆ CHANNEL_IS_OPENING

#define CHANNEL_IS_OPENING ( chan )

Value:

(channel_is_in_state((chan), \

CHANNEL_STATE_OPENING))

CHANNEL_STATE_OPENING

@ CHANNEL_STATE_OPENING

Definition: channel.h:70

Definition at line 690 of file channel.h.

Enumeration Type Documentation

◆ channel_listener_state_t

enum channel_listener_state_t

Enumerator
CHANNEL_LISTENER_STATE_CLOSED	Closed state - channel listener is inactive Permitted transitions from: CHANNEL_LISTENER_STATE_CLOSING Permitted transitions to: CHANNEL_LISTENER_STATE_LISTENING
CHANNEL_LISTENER_STATE_LISTENING	Listening state - channel listener is listening for incoming connections Permitted transitions from: CHANNEL_LISTENER_STATE_CLOSED Permitted transitions to: CHANNEL_LISTENER_STATE_CLOSING CHANNEL_LISTENER_STATE_ERROR
CHANNEL_LISTENER_STATE_CLOSING	Closing state - channel listener is shutting down Permitted transitions from: CHANNEL_LISTENER_STATE_LISTENING Permitted transitions to: CHANNEL_LISTENER_STATE_CLOSED, CHANNEL_LISTENER_STATE_ERROR
CHANNEL_LISTENER_STATE_ERROR	Error state - channel listener has experienced a permanent error Permitted transitions from: CHANNEL_STATE_CLOSING CHANNEL_STATE_LISTENING Permitted transitions to: None
CHANNEL_LISTENER_STATE_LAST	Placeholder for maximum state value

Definition at line 126 of file channel.h.

◆ channel_state_t

enum channel_state_t

Enumerator
CHANNEL_STATE_CLOSED	Closed state - channel is inactive Permitted transitions from: CHANNEL_STATE_CLOSING Permitted transitions to: CHANNEL_STATE_OPENING
CHANNEL_STATE_OPENING	Opening state - channel is trying to connect Permitted transitions from: CHANNEL_STATE_CLOSED Permitted transitions to: CHANNEL_STATE_CLOSING CHANNEL_STATE_ERROR CHANNEL_STATE_OPEN
CHANNEL_STATE_OPEN	Open state - channel is active and ready for use Permitted transitions from: CHANNEL_STATE_MAINT CHANNEL_STATE_OPENING Permitted transitions to: CHANNEL_STATE_CLOSING CHANNEL_STATE_ERROR CHANNEL_STATE_MAINT
CHANNEL_STATE_MAINT	Maintenance state - channel is temporarily offline for subclass specific maintenance activities such as TLS renegotiation. Permitted transitions from: CHANNEL_STATE_OPEN Permitted transitions to: CHANNEL_STATE_CLOSING CHANNEL_STATE_ERROR CHANNEL_STATE_OPEN
CHANNEL_STATE_CLOSING	Closing state - channel is shutting down Permitted transitions from: CHANNEL_STATE_MAINT CHANNEL_STATE_OPEN Permitted transitions to: CHANNEL_STATE_CLOSED, CHANNEL_STATE_ERROR
CHANNEL_STATE_ERROR	Error state - channel has experienced a permanent error Permitted transitions from: CHANNEL_STATE_CLOSING CHANNEL_STATE_MAINT CHANNEL_STATE_OPENING CHANNEL_STATE_OPEN Permitted transitions to: None
CHANNEL_STATE_LAST	Placeholder for maximum state value

Definition at line 50 of file channel.h.

◆ channel_usage_info_t

enum channel_usage_info_t

This enum is used by channelpadding to decide when to pad channels. Don't add values to it without updating the checks in channelpadding_decide_to_pad_channel().

Definition at line 32 of file channel.h.

◆ circ_id_type_t

enum circ_id_type_t

Possible rules for generating circuit IDs on an OR connection.

Enumerator
CIRC_ID_TYPE_LOWER	Pick from 0..1<<15-1.
CIRC_ID_TYPE_HIGHER	Pick from 1<<15..1<<16-1.
CIRC_ID_TYPE_NEITHER	The other side of a connection is an OP: never create circuits to it, and let it use any circuit ID it wants.

Definition at line 39 of file channel.h.

Function Documentation

◆ channel_check_for_duplicates()

void channel_check_for_duplicates ( void )

Relays run this once an hour to look over our list of channels to other relays. It prints out some statistics if there are multiple connections to many relays.

This function is similar to connection_or_set_bad_connections(), and probably could be adapted to replace it, if it was modified to actually take action on any of these connections.

Definition at line 748 of file channel.c.

◆ channel_clear_client()

void channel_clear_client ( channel_t * chan )

Clear the client flag.

Mark a channel as being not from a client.

Definition at line 2919 of file channel.c.

◆ channel_describe_peer()

const char* channel_describe_peer ( channel_t * chan )

Return text description of the remote endpoint canonical address.

This function returns a human-readable string for logging; nothing should parse it or rely on a particular format.

Subsequent calls to this function may invalidate its return value.

Definition at line 2815 of file channel.c.

◆ channel_describe_transport()

const char* channel_describe_transport ( channel_t * chan )

Describe the transport subclass for a channel.

Invoke a method to get a string description of the lower-layer transport for this channel.

Definition at line 2508 of file channel.c.

Referenced by channel_dump_statistics().

◆ channel_dump_statistics()

void channel_dump_statistics	(	channel_t *	chan,
		int	severity
	)

Dump channel statistics.

Dump statistics for one channel to the log.

Definition at line 2537 of file channel.c.

◆ channel_dump_transport_statistics()

void channel_dump_transport_statistics	(	channel_t *	chan,
		int	severity
	)

Invoke transport-specific stats dump for channel.

If there is a lower-layer statistics dump method, invoke it.

Definition at line 2785 of file channel.c.

◆ channel_dumpstats()

void channel_dumpstats ( int severity )

Dump channel statistics to the log.

This is called from dumpstats() in main.c and spams the log with statistics on channels.

Definition at line 2071 of file channel.c.

◆ channel_find_by_global_id()

channel_t* channel_find_by_global_id ( uint64_t global_identifier )

Channel lookups

Find channel by global ID.

This function searches for a channel by the global_identifier assigned at initialization time. This identifier is unique for the lifetime of the Tor process.

Definition at line 650 of file channel.c.

Referenced by circuitmux_set_policy().

◆ channel_free_all()

void channel_free_all ( void )

Close all channels and free everything.

This gets called from tor_free_all() in main.c to clean up on exit. It will close all registered channels and free associated storage, then free the all_channels, active_channels, listening_channels and finished_channels lists and also channel_identity_map.

Definition at line 2246 of file channel.c.

◆ channel_get_addr_if_possible()

int channel_get_addr_if_possible	(	const channel_t *	chan,
		tor_addr_t *	addr_out
	)

Get the remote address for this channel, if possible.

Write the remote address out to a tor_addr_t if the underlying transport supports this operation, and return 1. Return 0 if the underlying transport doesn't let us do this.

Always returns the "real" address of the peer – the one we're connected to on the internet.

Definition at line 2835 of file channel.c.

Referenced by channel_do_open_actions(), and channel_dump_statistics().

◆ channel_get_cell_handler()

channel_cell_handler_fn_ptr channel_get_cell_handler ( channel_t * chan )

Return the fixed-length cell handler for a channel.

This function gets the handler for incoming fixed-length cells installed on a channel.

Definition at line 1085 of file channel.c.

◆ channel_has_queued_writes()

int channel_has_queued_writes ( channel_t * chan )

Return true iff the channel has any cells on the connection outbuf waiting to be sent onto the network.

Definition at line 2849 of file channel.c.

◆ channel_is_bad_for_new_circs()

int channel_is_bad_for_new_circs ( channel_t * chan )

Check the is_bad_for_new_circs flag.

This function returns the is_bad_for_new_circs flag of the specified channel.

Definition at line 2865 of file channel.c.

Referenced by channel_is_better(), and connection_or_is_bad_for_new_circs().

◆ channel_is_better()

int channel_is_better	(	channel_t *	a,
		channel_t *	b
	)

Decide which of two channels to prefer for extending a circuit.

This function is called while extending a circuit and returns true iff a is 'better' than b. The most important criterion here is that a canonical channel is always better than a non-canonical one, but the number of circuits and the age are used as tie-breakers.

This is based on the former connection_or_is_better() of connection_or.c

Definition at line 2337 of file channel.c.

◆ channel_is_canonical()

int channel_is_canonical ( channel_t * chan )

Get the canonical flag for a channel.

This returns the is_canonical for a channel; this flag is determined by the lower layer and can't be set in a transport-independent way.

Definition at line 2933 of file channel.c.

Referenced by channel_is_better().

◆ channel_is_client()

int channel_is_client ( const channel_t * chan )

Get the client flag.

This returns the client flag of a channel, which will be set if command_process_create_cell() in command.c thinks this is a connection from a client.

Definition at line 2893 of file channel.c.

Referenced by channel_do_open_actions(), and circuit_expire_old_circuits_serverside().

◆ channel_is_incoming()

int channel_is_incoming ( channel_t * chan )

Test incoming flag.

This function gets the incoming flag; this is set when a listener spawns a channel. If this returns true the channel was remotely initiated.

Definition at line 2948 of file channel.c.

◆ channel_is_local()

int channel_is_local ( channel_t * chan )

Test local flag.

This function gets the local flag; the lower layer should set this when setting up the channel if is_local_addr() is true for all of the destinations it will communicate with on behalf of this channel. It's used to decide whether to declare the network reachable when seeing incoming traffic on the channel.

Definition at line 2979 of file channel.c.

◆ channel_is_outgoing()

int channel_is_outgoing ( channel_t * chan )

Test outgoing flag.

This function gets the outgoing flag; this is the inverse of the incoming bit set when a listener spawns a channel. If this returns true the channel was locally initiated.

Definition at line 3025 of file channel.c.

Referenced by channel_do_open_actions(), and channel_set_circid_type().

◆ channel_listener_describe_transport()

const char* channel_listener_describe_transport ( channel_listener_t * chan_l )

Describe the transport subclass for a channel listener.

Invoke a method to get a string description of the lower-layer transport for this channel listener.

Definition at line 2523 of file channel.c.

Referenced by channel_listener_dump_statistics().

◆ channel_listener_dump_statistics()

void channel_listener_dump_statistics	(	channel_listener_t *	chan_l,
		int	severity
	)

Dump channel listener statistics.

Dump statistics for one channel listener to the log.

Definition at line 2719 of file channel.c.

◆ channel_listener_dump_transport_statistics()

void channel_listener_dump_transport_statistics	(	channel_listener_t *	chan_l,
		int	severity
	)

Invoke transport-specific stats dump for channel listener.

If there is a lower-layer statistics dump method, invoke it.

Definition at line 2798 of file channel.c.

Referenced by channel_listener_dump_statistics().

◆ channel_listener_dumpstats()

void channel_listener_dumpstats ( int severity )

Dump channel listener statistics to the log.

This is called from dumpstats() in main.c and spams the log with statistics on channel listeners.

Definition at line 2102 of file channel.c.

◆ channel_listener_mark_for_close()

void channel_listener_mark_for_close ( channel_listener_t * chan_l )

Mark a channel listener for closure.

This function tries to close a channel_listener_t; it will go into the CLOSING state, and eventually the lower layer should put it into the CLOSED or ERROR state. Then, channel_run_cleanup() will eventually free it.

Definition at line 1176 of file channel.c.

◆ channel_listener_run_cleanup()

void channel_listener_run_cleanup ( void )

Clean up channel listeners.

This gets called periodically from run_scheduled_events() in main.c; it cleans up after closed channel listeners.

Definition at line 2159 of file channel.c.

Referenced by postloop_cleanup_cb().

◆ channel_listener_set_listener_fn()

void channel_listener_set_listener_fn	(	channel_listener_t *	chan_l,
		channel_listener_fn_ptr	listener
	)

Set the listener for a channel listener.

This function sets the handler for new incoming channels on a channel listener.

Definition at line 1062 of file channel.c.

Referenced by command_setup_listener().

◆ channel_listener_state_can_transition()

int channel_listener_state_can_transition	(	channel_listener_state_t	from,
		channel_listener_state_t	to
	)

Indicate whether a channel listener state transition is valid.

This function takes two channel listener states and indicates whether a transition between them is permitted (see the state definitions and transition table in or.h at the channel_listener_state_t typedef).

Definition at line 283 of file channel.c.

Referenced by channel_listener_change_state().

◆ channel_listener_state_is_valid()

int channel_listener_state_is_valid ( channel_listener_state_t state )

Indicate whether a given channel listener state is valid.

Definition at line 210 of file channel.c.

Referenced by channel_listener_change_state().

◆ channel_listener_state_to_string()

const char* channel_listener_state_to_string ( channel_listener_state_t state )

Return a human-readable description for a channel listener state.

Definition at line 350 of file channel.c.

Referenced by channel_listener_dump_statistics().

◆ channel_mark_as_used_for_origin_circuit()

void channel_mark_as_used_for_origin_circuit ( channel_t * chan )

Set the potentially_used_for_bootstrapping flag on the or_connection_t corresponding to the provided channel.

This flag indicates that if the connection fails, it might be interesting to the bootstrapping subsystem. (The bootstrapping system only cares about channels that we have tried to use for our own circuits. Other channels may have been launched in response to EXTEND cells from somebody else, and if they fail, it won't necessarily indicate a bootstrapping problem.)

Definition at line 374 of file channeltls.c.

◆ channel_mark_bad_for_new_circs()

void channel_mark_bad_for_new_circs ( channel_t * chan )

Mark a channel as bad for new circuits.

Set the is_bad_for_new_circs_flag on chan.

Definition at line 2878 of file channel.c.

◆ channel_mark_client()

void channel_mark_client ( channel_t * chan )

Set the client flag.

Mark a channel as being from a client.

Definition at line 2906 of file channel.c.

◆ channel_mark_for_close()

void channel_mark_for_close ( channel_t * chan )

Mark a channel for closure.

This function tries to close a channel_t; it will go into the CLOSING state, and eventually the lower layer should put it into the CLOSED or ERROR state. Then, channel_run_cleanup() will eventually free it.

Definition at line 1137 of file channel.c.

Referenced by channel_flush_from_first_active_circuit(), and channel_tls_listener_close_method().

◆ channel_matches_extend_info()

int channel_matches_extend_info	(	channel_t *	chan,
		extend_info_t *	extend_info
	)

Check if a channel matches an extend_info_t.

This function calls the lower layer and asks if this channel matches a given extend_info_t.

NOTE that this function only checks for an address/port match, and should be used only when no identity is available.

Definition at line 3270 of file channel.c.

Referenced by circuit_get_all_pending_on_channel().

◆ channel_next_with_rsa_identity()

channel_t* channel_next_with_rsa_identity ( channel_t * chan )

For things returned by channel_find_by_remote_digest(), walk the list. The RSA key will match for all returned elements; the Ed25519 key might not.

Get next channel with digest.

This function takes a channel and finds the next channel in the list with the same digest.

Definition at line 731 of file channel.c.

Referenced by channel_get_for_extend().

◆ channel_num_cells_writeable()

int channel_num_cells_writeable ( channel_t * chan )

Estimate the number of writeable cells.

Ask the lower layer for an estimate of how many cells it can accept.

Definition at line 3056 of file channel.c.

◆ channel_num_circuits()

unsigned int channel_num_circuits ( channel_t * chan )

Return the total number of circuits used by a channel.

Parameters

chan	Channel to query

Returns: Number of circuits using this as n_chan or p_chan

Definition at line 3316 of file channel.c.

Referenced by channel_is_better(), and connection_or_get_num_circuits().

◆ channel_remote_identity_matches()

int channel_remote_identity_matches	(	const channel_t *	chan,
		const char *	rsa_id_digest,
		const ed25519_public_key_t *	ed_id
	)

Return true iff chan matches rsa_id_digest and ed_id. as its identity keys. If either is NULL, do not check for a match.

Definition at line 667 of file channel.c.

◆ channel_run_cleanup()

void channel_run_cleanup ( void )

Clean up channels.

This gets called periodically from run_scheduled_events() in main.c; it cleans up after closed channels.

Definition at line 2133 of file channel.c.

Referenced by postloop_cleanup_cb().

◆ channel_send_destroy()

int channel_send_destroy	(	circid_t	circ_id,
		channel_t *	chan,
		int	reason
	)

Send destroy cell on a channel.

Write a destroy cell with circ ID circ_id and reason reason onto channel chan. Don't perform range-checking on reason: we may want to propagate reasons from other cells.

Definition at line 2031 of file channel.c.

◆ channel_set_cell_handlers()

void channel_set_cell_handlers	(	channel_t *	chan,
		channel_cell_handler_fn_ptr	cell_handler
	)

Set both cell handlers for a channel.

This function sets both the fixed-length and variable length cell handlers for a channel.

Definition at line 1102 of file channel.c.

Referenced by command_setup_channel().

◆ channel_set_circid_type()

void channel_set_circid_type	(	channel_t *	chan,
		crypto_pk_t *	identity_rcvd,
		int	consider_identity
	)

Set up circuit ID generation.

This is called when setting up a channel and replaces the old connection_or_set_circid_type().

Definition at line 3333 of file channel.c.

◆ channel_state_can_transition()

int channel_state_can_transition	(	channel_state_t	from,
		channel_state_t	to
	)

Indicate whether a channel state transition is valid.

This function takes two channel states and indicates whether a transition between them is permitted (see the state definitions and transition table in or.h at the channel_state_t typedef).

Definition at line 237 of file channel.c.

Referenced by channel_change_state_().

◆ channel_state_is_valid()

int channel_state_is_valid ( channel_state_t state )

Indicate whether a given channel state is valid.

Definition at line 185 of file channel.c.

Referenced by channel_change_state_().

◆ channel_state_to_string()

const char* channel_state_to_string ( channel_state_t state )

Return a human-readable description for a channel state.

Definition at line 315 of file channel.c.

Referenced by channel_dump_statistics().

◆ channel_timestamp_client()

void channel_timestamp_client ( channel_t * chan )

Update client timestamp.

This function is called by relay.c to timestamp a channel that appears to be used as a client.

Definition at line 3173 of file channel.c.

◆ channel_update_bad_for_new_circs()

void channel_update_bad_for_new_circs	(	const char *	digest,
		int	force
	)

Go through all the channels (or if digest is non-NULL, just the OR connections with that digest), and set the is_bad_for_new_circs flag based on the rules in connection_or_group_set_badness() (or just always set it if force is true).

Definition at line 3438 of file channel.c.

Referenced by second_elapsed_callback().

◆ channel_when_created()

time_t channel_when_created ( channel_t * chan )

Query created timestamp for a channel.

Definition at line 3231 of file channel.c.

Referenced by channel_is_better().

◆ channel_when_last_client()

time_t channel_when_last_client ( channel_t * chan )

Query client timestamp.

Definition at line 3242 of file channel.c.

Referenced by connection_or_client_used().

◆ channel_when_last_xmit()

time_t channel_when_last_xmit ( channel_t * chan )

Query xmit timestamp.

Definition at line 3253 of file channel.c.

Referenced by circuit_expire_old_circuits_serverside().

◆ channel_write_packed_cell()

int channel_write_packed_cell	(	channel_t *	chan,
		packed_cell_t *	cell
	)

Write a packed cell to a channel.

Write a packed cell to a channel using the write_cell() method. This is called by the transport-independent code to deliver a packed cell to a channel for transmission.

Return 0 on success else a negative value. In both cases, the caller should not access the cell anymore, it is freed both on success and error.

Definition at line 1484 of file channel.c.

Referenced by channel_flush_from_first_active_circuit().

◆ packed_cell_is_destroy()

int packed_cell_is_destroy	(	channel_t *	chan,
		const packed_cell_t *	packed_cell,
		circid_t *	circid_out
	)

If packed_cell on chan is a destroy cell, then set *circid_out to its circuit ID, and return true. Otherwise, return false.

Definition at line 2005 of file channel.c.

Data Structures

Macros

Typedefs

Enumerations

Functions

Detailed Description

Macro Definition Documentation

◆ CHANNEL_CAN_HANDLE_CELLS

◆ CHANNEL_CONDEMNED

◆ CHANNEL_FINISHED

◆ CHANNEL_IS_CLOSED

◆ CHANNEL_IS_CLOSING

◆ CHANNEL_IS_ERROR

◆ CHANNEL_IS_MAINT

◆ CHANNEL_IS_OPEN

◆ CHANNEL_IS_OPENING

Enumeration Type Documentation

◆ channel_listener_state_t

◆ channel_state_t

◆ channel_usage_info_t

◆ circ_id_type_t

Function Documentation

◆ channel_check_for_duplicates()

◆ channel_clear_client()

◆ channel_describe_peer()

◆ channel_describe_transport()

◆ channel_dump_statistics()

◆ channel_dump_transport_statistics()

◆ channel_dumpstats()

◆ channel_find_by_global_id()

◆ channel_free_all()

◆ channel_get_addr_if_possible()

◆ channel_get_cell_handler()

◆ channel_has_queued_writes()

◆ channel_is_bad_for_new_circs()

◆ channel_is_better()

◆ channel_is_canonical()

◆ channel_is_client()

◆ channel_is_incoming()

◆ channel_is_local()

◆ channel_is_outgoing()

◆ channel_listener_describe_transport()

◆ channel_listener_dump_statistics()

◆ channel_listener_dump_transport_statistics()

◆ channel_listener_dumpstats()

◆ channel_listener_mark_for_close()

◆ channel_listener_run_cleanup()

◆ channel_listener_set_listener_fn()

◆ channel_listener_state_can_transition()

◆ channel_listener_state_is_valid()

◆ channel_listener_state_to_string()

◆ channel_mark_as_used_for_origin_circuit()

◆ channel_mark_bad_for_new_circs()

◆ channel_mark_client()

◆ channel_mark_for_close()

◆ channel_matches_extend_info()

◆ channel_next_with_rsa_identity()

◆ channel_num_cells_writeable()

◆ channel_num_circuits()

◆ channel_remote_identity_matches()

◆ channel_run_cleanup()

◆ channel_send_destroy()

◆ channel_set_cell_handlers()

◆ channel_set_circid_type()

◆ channel_state_can_transition()

◆ channel_state_is_valid()

◆ channel_state_to_string()

◆ channel_timestamp_client()

◆ channel_update_bad_for_new_circs()

◆ channel_when_created()

◆ channel_when_last_client()

◆ channel_when_last_xmit()

◆ channel_write_packed_cell()

◆ packed_cell_is_destroy()