Implement circuitmux_attach_circuit() in circuitmux.c

This commit is contained in:
Andrea Shepard 2012-09-26 00:56:26 -07:00
parent e4a11b890e
commit 3c41d7f414
2 changed files with 236 additions and 6 deletions

View File

@ -7,6 +7,7 @@
**/
#include "or.h"
#include "channel.h"
#include "circuitmux.h"
/*
@ -70,6 +71,9 @@ struct circuitmux_s {
/* Keep count of attached, active circuits */
unsigned int n_circuits, n_active_circuits;
/* Total number of queued cells on all circuits */
unsigned int n_cells;
/*
* Map from (channel ID, circuit ID) pairs to circuit_muxinfo_t
*/
@ -102,11 +106,14 @@ struct circuitmux_s {
/*
* This struct holds whatever we want to store per attached circuit on a
* circuitmux_t; right now, just the count of queued cells.
* circuitmux_t; right now, just the count of queued cells and the direction.
*/
struct circuit_muxinfo_s {
/* Count of cells on this circuit at last update */
unsigned int cell_count;
/* Direction of flow */
cell_direction_t direction;
};
/*
@ -168,6 +175,10 @@ HT_GENERATE(chanid_circid_muxinfo_map, chanid_circid_muxinfo_t, node,
chanid_circid_entry_hash, chanid_circid_entries_eq, 0.6,
malloc, realloc, free);
/*
* Circuitmux alloc/free functions
*/
/**
* Allocate a new circuitmux_t
*/
@ -207,3 +218,226 @@ circuitmux_free(circuitmux_t *cmux)
tor_free(cmux);
}
/*
* Circuitmux/circuit attachment status inquiry functions
*/
/**
* Query the direction of an attached circuit
*/
cell_direction_t
circuitmux_attached_circuit_direction(circuitmux_t *cmux, circuit_t *circ)
{
chanid_circid_muxinfo_t *hashent = NULL;
/* Try to find a map entry */
hashent = circuitmux_find_map_entry(cmux, circ);
/*
* This function should only be called on attached circuits; assert that
* we had a map entry.
*/
tor_assert(hashent);
/* Return the direction from the map entry */
return hashent->muxinfo.direction;
}
/**
* Find an entry in the cmux's map for this circuit or return NULL if there
* is none.
*/
static chanid_circid_muxinfo_t *
circuitmux_find_map_entry(circuitmux_t *cmux, circuit_t *circ)
{
chanid_circid_muxinfo_t search, *hashent = NULL;
/* Sanity-check parameters */
tor_assert(cmux);
tor_assert(cmux->chanid_circid_map);
tor_assert(circ);
tor_assert(circ->n_chan);
/* Okay, let's see if it's attached for n_chan/n_circ_id */
search.chan_id = circ->n_chan->global_identifier;
search.circ_id = circ->n_circ_id;
/* Query */
hashent = HT_FIND(chanid_circid_muxinfo_map, cmux->chanid_circid_map,
&search);
/* Found something? */
if (hashent) {
/*
* Assert that the direction makes sense for a hashent we found by
* n_chan/n_circ_id before we return it.
*/
tor_assert(hashent->muxinfo.direction == CELL_DIRECTION_OUT);
} else {
/* Not there, have we got a p_chan/p_circ_id to try? */
if (circ->magic == OR_CIRCUIT_MAGIC) {
search.circ_id = TO_OR_CIRCUIT(circ)->p_circ_id;
/* Check for p_chan */
if (TO_OR_CIRCUIT(circ)->p_chan) {
search.chan_id = TO_OR_CIRCUIT(circ)->p_chan->global_identifier;
/* Okay, search for that */
hashent = HT_FIND(chanid_circid_muxinfo_map, cmux->chanid_circid_map,
&search);
/* Find anything? */
if (hashent) {
/* Assert that the direction makes sense before we return it */
tor_assert(hashent->muxinfo.direction == CELL_DIRECTION_IN);
}
}
}
}
/* Okay, hashent is it if it was there */
return hashent;
}
/**
* Query whether a circuit is attached to a circuitmux
*/
int
circuitmux_is_circuit_attached(circuitmux_t *cmux, circuit_t *circ)
{
chanid_circid_muxinfo_t *hashent = NULL;
/* Look if it's in the circuit map */
hashent = circuitmux_find_map_entry(cmux, circ);
return (hashent != NULL);
}
/*
* Functions for circuit code to call to update circuit status
*/
/**
* Attach a circuit to a circuitmux, for the specified direction.
*/
void
circuitmux_attach_circuit(circuitmux_t *cmux, circuit_t *circ,
cell_direction_t direction)
{
channel_t *chan = NULL;
uint64_t channel_id;
circid_t circ_id;
chanid_circid_muxinfo_t search, *hashent = NULL;
unsigned int cell_count;
tor_assert(cmux);
tor_assert(circ);
tor_assert(direction == CELL_DIRECTION_IN ||
direction == CELL_DIRECTION_OUT);
/*
* Figure out which channel we're using, and get the circuit's current
* cell count and circuit ID.
*/
if (direction == CELL_DIRECTION_OUT) {
/* It's n_chan */
chan = circ->n_chan;
cell_count = circ->n_chan_cells.n;
circ_id = circ->n_circ_id;
} else {
/* We want p_chan */
chan = TO_OR_CIRCUIT(circ)->p_chan;
cell_count = TO_OR_CIRCUIT(circ)->p_chan_cells.n;
circ_id = TO_OR_CIRCUIT(circ)->p_circ_id;
}
/* Assert that we did get a channel */
tor_assert(chan);
/* Assert that the circuit ID is sensible */
tor_assert(circ_id != 0);
/* Get the channel ID */
channel_id = chan->global_identifier;
/* See if we already have this one */
search.chan_id = channel_id;
search.circ_id = circ_id;
hashent = HT_FIND(chanid_circid_muxinfo_map, cmux->chanid_circid_map,
&search);
if (hashent) {
/*
* This circuit was already attached to this cmux; make sure the
* directions match and update the cell count and active circuit count.
*/
log_info(LD_CIRC,
"Circuit %u on channel " U64_FORMAT " was already attached to "
"cmux %p (trying to attach to %p)",
circ_id, U64_PRINTF_ARG(channel_id),
circ->mux, cmux);
/*
* The mux pointer on the circuit should match this cmux, and the
* direction in result should match; otherwise assert.
*/
tor_assert(circ->mux == cmux);
tor_assert(hashent->muxinfo.direction == direction);
/*
* Looks okay; just update the cell count and active circuits if we must
*/
if (hashent->muxinfo.cell_count > 0 && cell_count == 0) {
--(cmux->n_active_circuits);
} else if (hashent->muxinfo.cell_count == 0 && cell_count > 0) {
++(cmux->n_active_circuits);
}
cmux->n_cells -= hashent->muxinfo.cell_count;
cmux->n_cells += cell_count;
hashent->muxinfo.cell_count = cell_count;
/* TODO update active_circuits / active_circuit_pqueue */
} else {
/*
* New circuit; add an entry and update the circuit/active circuit
* counts.
*/
log_debug(LD_CIRC,
"Attaching circuit %u on channel " U64_FORMAT " to cmux %p",
circ_id, U64_PRINTF_ARG(channel_id), cmux);
/* Assert that the circuit doesn't already have a mux */
tor_assert(circ->mux == NULL);
/* Insert it in the map */
hashent = tor_malloc_zero(sizeof(*hashent));
hashent->chan_id = channel_id;
hashent->circ_id = circ_id;
hashent->muxinfo.cell_count = cell_count;
hashent->muxinfo.direction = direction;
HT_INSERT(chanid_circid_muxinfo_map, cmux->chanid_circid_map,
hashent);
/* Set the circuit's mux */
circ->mux = cmux;
/* Make sure the next/prev pointers are NULL */
if (direction == CELL_DIRECTION_OUT) {
circ->next_active_on_n_chan = NULL;
circ->prev_active_on_n_chan = NULL;
} else {
TO_OR_CIRCUIT(circ)->next_active_on_p_chan = NULL;
TO_OR_CIRCUIT(circ)->prev_active_on_p_chan = NULL;
}
/* Update counters */
++(cmux->n_circuits);
if (cell_count > 0) {
++(cmux->n_active_circuits);
circuitmux_make_circuit_active(cmux, circ, direction);
}
cmux->n_cells += cell_count;
/* TODO update active_circuits / active_circuit_pqueue */
}
}

View File

@ -2641,11 +2641,7 @@ typedef struct circuit_t {
* The circuit_id used in the next (forward) hop of this circuit;
* this is unique to n_chan, but this ordered pair is globally
* unique:
<<<<<<< HEAD
*
=======
*
>>>>>>> f1e8169... Use circuitmux_t in channels and when relaying cells
* (n_chan->global_identifier, n_circ_id)
*/
circid_t n_circ_id;