diff options
| -rw-r--r-- | sys/netinet/tcp_syncache.c | 26 |
1 files changed, 18 insertions, 8 deletions
diff --git a/sys/netinet/tcp_syncache.c b/sys/netinet/tcp_syncache.c index 68b5ac8..a824316 100644 --- a/sys/netinet/tcp_syncache.c +++ b/sys/netinet/tcp_syncache.c @@ -42,6 +42,7 @@ __FBSDID("$FreeBSD$"); #include <sys/systm.h> #include <sys/kernel.h> #include <sys/sysctl.h> +#include <sys/limits.h> #include <sys/lock.h> #include <sys/mutex.h> #include <sys/malloc.h> @@ -111,7 +112,7 @@ SYSCTL_INT(_net_inet_tcp, OID_AUTO, syncookies_only, CTLFLAG_RW, struct syncache { TAILQ_ENTRY(syncache) sc_hash; struct in_conninfo sc_inc; /* addresses */ - u_long sc_rxttime; /* retransmit time */ + int sc_rxttime; /* retransmit time */ u_int16_t sc_rxmits; /* retransmit counter */ u_int32_t sc_tsreflect; /* timestamp to reflect */ @@ -183,7 +184,7 @@ static struct syncache /* * Transmit the SYN,ACK fewer times than TCP_MAXRXTSHIFT specifies. - * 3 retransmits corresponds to a timeout of (1 + 2 + 4 + 8 == 15) seconds, + * 3 retransmits corresponds to a timeout of 3 * (1 + 2 + 4 + 8) == 45 seconds, * the odds are that the user has given up attempting to connect by then. */ #define SYNCACHE_MAXREXMTS 3 @@ -344,6 +345,8 @@ syncache_insert(struct syncache *sc, struct syncache_head *sch) sch->sch_length++; /* Reinitialize the bucket row's timer. */ + if (sch->sch_length == 1) + sch->sch_nextc = ticks + INT_MAX; syncache_timeout(sc, sch, 1); SCH_UNLOCK(sch); @@ -382,11 +385,12 @@ syncache_timeout(struct syncache *sc, struct syncache_head *sch, int docallout) sc->sc_rxttime = ticks + TCPTV_RTOBASE * (tcp_backoff[sc->sc_rxmits]); sc->sc_rxmits++; - if (sch->sch_nextc > sc->sc_rxttime) + if (TSTMP_LT(sc->sc_rxttime, sch->sch_nextc)) { sch->sch_nextc = sc->sc_rxttime; - if (!TAILQ_EMPTY(&sch->sch_bucket) && docallout) - callout_reset(&sch->sch_timer, sch->sch_nextc - ticks, - syncache_timer, (void *)sch); + if (docallout) + callout_reset(&sch->sch_timer, sch->sch_nextc - ticks, + syncache_timer, (void *)sch); + } } /* @@ -405,6 +409,12 @@ syncache_timer(void *xsch) /* NB: syncache_head has already been locked by the callout. */ SCH_LOCK_ASSERT(sch); + /* + * In the following cycle we may remove some entries and/or + * advance some timeouts, so re-initialize the bucket timer. + */ + sch->sch_nextc = tick + INT_MAX; + TAILQ_FOREACH_SAFE(sc, &sch->sch_bucket, sc_hash, nsc) { /* * We do not check if the listen socket still exists @@ -414,8 +424,8 @@ syncache_timer(void *xsch) * then the RST will be sent by the time the remote * host does the SYN/ACK->ACK. */ - if (sc->sc_rxttime > tick) { - if (sc->sc_rxttime < sch->sch_nextc) + if (TSTMP_GT(sc->sc_rxttime, tick)) { + if (TSTMP_LT(sc->sc_rxttime, sch->sch_nextc)) sch->sch_nextc = sc->sc_rxttime; continue; } |
