diff options
Diffstat (limited to 'framework/src/suricata/src/defrag-timeout.c')
| -rw-r--r-- | framework/src/suricata/src/defrag-timeout.c | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/framework/src/suricata/src/defrag-timeout.c b/framework/src/suricata/src/defrag-timeout.c new file mode 100644 index 00000000..663ee3b5 --- /dev/null +++ b/framework/src/suricata/src/defrag-timeout.c @@ -0,0 +1,153 @@ +/* Copyright (C) 2007-2012 Open Information Security Foundation + * + * You can copy, redistribute or modify this Program under the terms of + * the GNU General Public License version 2 as published by the Free + * Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * version 2 along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + */ + +/** + * \file + * + * \author Victor Julien <victor@inliniac.net> + */ + +#include "suricata-common.h" +#include "defrag.h" +#include "defrag-hash.h" + +uint32_t DefragTrackerGetSpareCount(void) +{ + return DefragTrackerSpareQueueGetSize(); +} + +uint32_t DefragTrackerGetActiveCount(void) +{ + return SC_ATOMIC_GET(defragtracker_counter); +} + +/** \internal + * \brief See if we can really discard this tracker. Check use_cnt reference. + * + * \param dt tracker + * \param ts timestamp + * + * \retval 0 not timed out just yet + * \retval 1 fully timed out, lets kill it + */ +static int DefragTrackerTimedOut(DefragTracker *dt, struct timeval *ts) +{ + /** never prune a trackers that is used by a packet + * we are currently processing in one of the threads */ + if (SC_ATOMIC_GET(dt->use_cnt) > 0) { + return 0; + } + + /* retain if remove is not set and not timed out */ + if (!dt->remove && timercmp(&dt->timeout, ts, >)) + return 0; + + return 1; +} + +/** + * \internal + * + * \brief check all trackers in a hash row for timing out + * + * \param hb tracker hash row *LOCKED* + * \param dt last tracker in the hash row + * \param ts timestamp + * + * \retval cnt timed out tracker + */ +static uint32_t DefragTrackerHashRowTimeout(DefragTrackerHashRow *hb, DefragTracker *dt, struct timeval *ts) +{ + uint32_t cnt = 0; + + do { + if (SCMutexTrylock(&dt->lock) != 0) { + dt = dt->hprev; + continue; + } + + DefragTracker *next_dt = dt->hprev; + + /* check if the tracker is fully timed out and + * ready to be discarded. */ + if (DefragTrackerTimedOut(dt, ts) == 1) { + /* remove from the hash */ + if (dt->hprev != NULL) + dt->hprev->hnext = dt->hnext; + if (dt->hnext != NULL) + dt->hnext->hprev = dt->hprev; + if (hb->head == dt) + hb->head = dt->hnext; + if (hb->tail == dt) + hb->tail = dt->hprev; + + dt->hnext = NULL; + dt->hprev = NULL; + + DefragTrackerClearMemory(dt); + + /* no one is referring to this tracker, use_cnt 0, removed from hash + * so we can unlock it and move it back to the spare queue. */ + SCMutexUnlock(&dt->lock); + + /* move to spare list */ + DefragTrackerMoveToSpare(dt); + + cnt++; + } else { + SCMutexUnlock(&dt->lock); + } + + dt = next_dt; + } while (dt != NULL); + + return cnt; +} + +/** + * \brief time out tracker from the hash + * + * \param ts timestamp + * + * \retval cnt number of timed out tracker + */ +uint32_t DefragTimeoutHash(struct timeval *ts) +{ + uint32_t idx = 0; + uint32_t cnt = 0; + + for (idx = 0; idx < defrag_config.hash_size; idx++) { + DefragTrackerHashRow *hb = &defragtracker_hash[idx]; + + if (DRLOCK_TRYLOCK(hb) != 0) + continue; + + /* defrag hash bucket is now locked */ + + if (hb->tail == NULL) { + DRLOCK_UNLOCK(hb); + continue; + } + + /* we have a tracker, or more than one */ + cnt += DefragTrackerHashRowTimeout(hb, hb->tail, ts); + DRLOCK_UNLOCK(hb); + } + + return cnt; +} + |