commit 86d9d85dfc177b7a24051f64a5c35997de5c9ac9 Author: Andrea Shepard <andrea@torproject.org> Date: Thu Sep 27 13:42:47 2012 -0700 Implement circuitmux_clear_policy(), circuitmux_get_policy() and circuitmux_set_policy() in circuitmux.c --- src/or/circuitmux.c | 159 ++++++++++++++++++++++++++++++++++++++++++++++++++- 1 files changed, 158 insertions(+), 1 deletions(-) diff --git a/src/or/circuitmux.c b/src/or/circuitmux.c index 53d3a1b..4e33569 100644 --- a/src/or/circuitmux.c +++ b/src/or/circuitmux.c @@ -343,7 +343,13 @@ circuitmux_free(circuitmux_t *cmux) tor_assert(cmux->n_circuits == 0); tor_assert(cmux->n_active_circuits == 0); - /* Free policy-specific data if we have any */ + /* + * Free policy-specific data if we have any; we don't + * need to do circuitmux_set_policy(cmux, NULL) to cover + * the circuits because they would have been handled in + * circuitmux_detach_all_circuits() before this was + * called. + */ if (cmux->policy && cmux->policy->free_cmux_data) { if (cmux->policy_data) { cmux->policy->free_cmux_data(cmux, cmux->policy_data); @@ -360,6 +366,157 @@ circuitmux_free(circuitmux_t *cmux) } /* + * Circuitmux policy control functions + */ + +/** + * Remove any policy installed on cmux; all policy data will be freed and + * cmux behavior will revert to the built-in round-robin active_circuits + * mechanism. + */ + +void +circuitmux_clear_policy(circuitmux_t *cmux) +{ + tor_assert(cmux); + + /* Internally, this is just setting policy to NULL */ + if (cmux->policy) { + circuitmux_set_policy(cmux, NULL); + } +} + +/** + * Return the policy currently installed on a circuitmux_t + */ + +const circuitmux_policy_t * +circuitmux_get_policy(circuitmux_t *cmux) +{ + tor_assert(cmux); + + return cmux->policy; +} + +/** + * Set policy; allocate for new policy, detach all circuits from old policy + * if any, attach them to new policy, and free old policy data. + */ + +void +circuitmux_set_policy(circuitmux_t *cmux, + const circuitmux_policy_t *pol) +{ + const circuitmux_policy_t *old_pol = NULL, *new_pol = NULL; + circuitmux_policy_data_t *old_pol_data = NULL, *new_pol_data = NULL; + chanid_circid_muxinfo_t **i = NULL; + channel_t *chan = NULL; + uint64_t last_chan_id_searched = 0; + circuit_t *circ = NULL; + + tor_assert(cmux); + + /* Set up variables */ + old_pol = cmux->policy; + old_pol_data = cmux->policy_data; + new_pol = pol; + + /* Check if this is the trivial case */ + if (old_pol == new_pol) return; + + /* Allocate data for new policy, if any */ + if (new_pol && new_pol->alloc_cmux_data) { + /* + * If alloc_cmux_data is not null, then we expect to get some policy + * data. Assert that we also have free_cmux_data so we can free it + * when the time comes, and allocate it. + */ + tor_assert(new_pol->free_cmux_data); + new_pol_data = new_pol->alloc_cmux_data(cmux); + tor_assert(new_pol_data); + } + + /* Install new policy and new policy data on cmux */ + cmux->policy = new_pol; + cmux->policy_data = new_pol_data; + + /* Iterate over all circuits, attaching/detaching each one */ + i = HT_START(chanid_circid_muxinfo_map, cmux->chanid_circid_map); + while (i) { + /* Assert that this entry isn't NULL */ + tor_assert(*i); + + /* + * Get the channel; since normal case is all circuits on the mux share a + * channel, we cache last_chan_id_searched + */ + if (!chan || last_chan_id_searched != (*i)->chan_id) { + chan = channel_find_by_global_id((*i)->chan_id); + last_chan_id_searched = (*i)->chan_id; + } + tor_assert(chan); + + /* Get the circuit */ + circ = circuit_get_by_circid_channel((*i)->circ_id, chan); + tor_assert(circ); + + /* Need to tell old policy it becomes inactive (i.e., it is active) ? */ + if (old_pol && old_pol->notify_circ_inactive && + (*i)->muxinfo.cell_count > 0) { + old_pol->notify_circ_inactive(cmux, old_pol_data, circ, + (*i)->muxinfo.policy_data); + } + + /* Need to free old policy data? */ + if ((*i)->muxinfo.policy_data) { + /* Assert that we have the means to free it if we have policy data */ + tor_assert(old_pol); + tor_assert(old_pol->free_circ_data); + /* Free it */ + old_pol->free_circ_data(cmux, old_pol_data, circ, + (*i)->muxinfo.policy_data); + (*i)->muxinfo.policy_data = NULL; + } + + /* Need to allocate new policy data? */ + if (new_pol && new_pol->alloc_circ_data) { + /* + * If alloc_circ_data is not null, we expect to get some per-circuit + * policy data. Assert that we also have free_circ_data so we can + * free it when the time comes, and allocate it. + */ + tor_assert(new_pol->free_circ_data); + (*i)->muxinfo.policy_data = + new_pol->alloc_circ_data(cmux, new_pol_data, circ, + (*i)->muxinfo.direction, + (*i)->muxinfo.cell_count); + } + + /* Need to make active on new policy? */ + if (new_pol && new_pol->notify_circ_active && + (*i)->muxinfo.cell_count > 0) { + new_pol->notify_circ_active(cmux, new_pol_data, circ, + (*i)->muxinfo.policy_data); + } + + /* Advance to next circuit map entry */ + i = HT_NEXT(chanid_circid_muxinfo_map, cmux->chanid_circid_map, i); + } + + /* Free data for old policy, if any */ + if (old_pol_data) { + /* + * If we had old policy data, we should have an old policy and a free + * function for it. + */ + tor_assert(old_pol); + tor_assert(old_pol->free_cmux_data); + old_pol->free_cmux_data(cmux, old_pol_data); + old_pol_data = NULL; + } +} + +/* * Circuitmux/circuit attachment status inquiry functions */