diff options
| author | Florian Westphal <fw@strlen.de> | 2012-09-17 00:23:09 +0000 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2012-09-24 14:29:01 +0200 |
| commit | 54eb3df3a7d01b6cd395bdc1098280f2f93fbec5 (patch) | |
| tree | 04a496fedd3b312e9f754e8636a75d6be2da2e52 | |
| parent | 3e0304a583d72c747caa8afac76b8d514aa293f5 (diff) | |
| download | lwn-54eb3df3a7d01b6cd395bdc1098280f2f93fbec5.tar.gz lwn-54eb3df3a7d01b6cd395bdc1098280f2f93fbec5.zip | |
netfilter: xt_time: add support to ignore day transition
Currently, if you want to do something like:
"match Monday, starting 23:00, for two hours"
You need two rules, one for Mon 23:00 to 0:00 and one for Tue 0:00-1:00.
The rule: --weekdays Mo --timestart 23:00 --timestop 01:00
looks correct, but it will first match on monday from midnight to 1 a.m.
and then again for another hour from 23:00 onwards.
This permits userspace to explicitly ignore the day transition and
match for a single, continuous time period instead.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| -rw-r--r-- | include/linux/netfilter/xt_time.h | 5 | ||||
| -rw-r--r-- | net/netfilter/xt_time.c | 24 |
2 files changed, 28 insertions, 1 deletions
diff --git a/include/linux/netfilter/xt_time.h b/include/linux/netfilter/xt_time.h index 7c37fac576c4..095886019396 100644 --- a/include/linux/netfilter/xt_time.h +++ b/include/linux/netfilter/xt_time.h @@ -17,6 +17,9 @@ enum { /* Match against local time (instead of UTC) */ XT_TIME_LOCAL_TZ = 1 << 0, + /* treat timestart > timestop (e.g. 23:00-01:00) as single period */ + XT_TIME_CONTIGUOUS = 1 << 1, + /* Shortcuts */ XT_TIME_ALL_MONTHDAYS = 0xFFFFFFFE, XT_TIME_ALL_WEEKDAYS = 0xFE, @@ -24,4 +27,6 @@ enum { XT_TIME_MAX_DAYTIME = 24 * 60 * 60 - 1, }; +#define XT_TIME_ALL_FLAGS (XT_TIME_LOCAL_TZ|XT_TIME_CONTIGUOUS) + #endif /* _XT_TIME_H */ diff --git a/net/netfilter/xt_time.c b/net/netfilter/xt_time.c index c48975ff8ea2..0ae55a36f492 100644 --- a/net/netfilter/xt_time.c +++ b/net/netfilter/xt_time.c @@ -42,6 +42,7 @@ static const u_int16_t days_since_leapyear[] = { */ enum { DSE_FIRST = 2039, + SECONDS_PER_DAY = 86400, }; static const u_int16_t days_since_epoch[] = { /* 2039 - 2030 */ @@ -78,7 +79,7 @@ static inline unsigned int localtime_1(struct xtm *r, time_t time) unsigned int v, w; /* Each day has 86400s, so finding the hour/minute is actually easy. */ - v = time % 86400; + v = time % SECONDS_PER_DAY; r->second = v % 60; w = v / 60; r->minute = w % 60; @@ -199,6 +200,18 @@ time_mt(const struct sk_buff *skb, struct xt_action_param *par) if (packet_time < info->daytime_start && packet_time > info->daytime_stop) return false; + + /** if user asked to ignore 'next day', then e.g. + * '1 PM Wed, August 1st' should be treated + * like 'Tue 1 PM July 31st'. + * + * This also causes + * 'Monday, "23:00 to 01:00", to match for 2 hours, starting + * Monday 23:00 to Tuesday 01:00. + */ + if ((info->flags & XT_TIME_CONTIGUOUS) && + packet_time <= info->daytime_stop) + stamp -= SECONDS_PER_DAY; } localtime_2(¤t_time, stamp); @@ -227,6 +240,15 @@ static int time_mt_check(const struct xt_mtchk_param *par) return -EDOM; } + if (info->flags & ~XT_TIME_ALL_FLAGS) { + pr_info("unknown flags 0x%x\n", info->flags & ~XT_TIME_ALL_FLAGS); + return -EINVAL; + } + + if ((info->flags & XT_TIME_CONTIGUOUS) && + info->daytime_start < info->daytime_stop) + return -EINVAL; + return 0; } |