From 56766b1fff76fe0c4770de848acfff9b524a8ac8 Mon Sep 17 00:00:00 2001 From: JP Abgrall Date: Thu, 26 Apr 2012 23:28:35 -0700 Subject: [PATCH] netfilter: xt_IDLETIMER: Add new netlink msg type Send notifications when the label becomes active after an idle period. Send netlink message notifications in addition to sysfs notifications. Using a uevent with subsystem=xt_idletimer INTERFACE=... STATE={active,inactive} This is backport from common android-3.0 commit: beb914e987cbbd368988d2b94a6661cb907c4d5a with uevent support instead of a new netlink message type. Change-Id: I31677ef00c94b5f82c8457e5bf9e5e584c23c523 Signed-off-by: Ashish Sharma Signed-off-by: JP Abgrall --- include/uapi/linux/netfilter/xt_IDLETIMER.h | 8 +++ net/netfilter/xt_IDLETIMER.c | 78 +++++++++++++++++++-- 2 files changed, 79 insertions(+), 7 deletions(-) diff --git a/include/uapi/linux/netfilter/xt_IDLETIMER.h b/include/uapi/linux/netfilter/xt_IDLETIMER.h index 208ae9387331..faaa28b3d061 100644 --- a/include/uapi/linux/netfilter/xt_IDLETIMER.h +++ b/include/uapi/linux/netfilter/xt_IDLETIMER.h @@ -4,6 +4,7 @@ * Header file for Xtables timer target module. * * Copyright (C) 2004, 2010 Nokia Corporation + * * Written by Timo Teras * * Converted to x_tables and forward-ported to 2.6.34 @@ -32,12 +33,19 @@ #include #define MAX_IDLETIMER_LABEL_SIZE 28 +#define NLMSG_MAX_SIZE 64 + +#define NL_EVENT_TYPE_INACTIVE 0 +#define NL_EVENT_TYPE_ACTIVE 1 struct idletimer_tg_info { __u32 timeout; char label[MAX_IDLETIMER_LABEL_SIZE]; + /* Use netlink messages for notification in addition to sysfs */ + __u8 send_nl_msg; + /* for kernel module internal use only */ struct idletimer_tg *timer __attribute__((aligned(8))); }; diff --git a/net/netfilter/xt_IDLETIMER.c b/net/netfilter/xt_IDLETIMER.c index 29d2c31f406c..fd1df37dbe30 100644 --- a/net/netfilter/xt_IDLETIMER.c +++ b/net/netfilter/xt_IDLETIMER.c @@ -5,6 +5,7 @@ * After timer expires a kevent will be sent. * * Copyright (C) 2004, 2010 Nokia Corporation + * * Written by Timo Teras * * Converted to x_tables and reworked for upstream inclusion @@ -38,8 +39,10 @@ #include #include #include +#include #include #include +#include struct idletimer_tg_attr { struct attribute attr; @@ -56,6 +59,8 @@ struct idletimer_tg { struct idletimer_tg_attr attr; unsigned int refcnt; + bool send_nl_msg; + bool active; }; static LIST_HEAD(idletimer_tg_list); @@ -63,6 +68,32 @@ static DEFINE_MUTEX(list_mutex); static struct kobject *idletimer_tg_kobj; +static void notify_netlink_uevent(const char *iface, struct idletimer_tg *timer) +{ + char iface_msg[NLMSG_MAX_SIZE]; + char state_msg[NLMSG_MAX_SIZE]; + char *envp[] = { iface_msg, state_msg, NULL }; + int res; + + res = snprintf(iface_msg, NLMSG_MAX_SIZE, "INTERFACE=%s", + iface); + if (NLMSG_MAX_SIZE <= res) { + pr_err("message too long (%d)", res); + return; + } + res = snprintf(state_msg, NLMSG_MAX_SIZE, "STATE=%s", + timer->active ? "active" : "inactive"); + if (NLMSG_MAX_SIZE <= res) { + pr_err("message too long (%d)", res); + return; + } + pr_debug("putting nlmsg: <%s> <%s>\n", iface_msg, state_msg); + kobject_uevent_env(idletimer_tg_kobj, KOBJ_CHANGE, envp); + return; + + +} + static struct idletimer_tg *__idletimer_tg_find_by_label(const char *label) { @@ -83,6 +114,7 @@ static ssize_t idletimer_tg_show(struct kobject *kobj, struct attribute *attr, { struct idletimer_tg *timer; unsigned long expires = 0; + unsigned long now = jiffies; mutex_lock(&list_mutex); @@ -92,11 +124,15 @@ static ssize_t idletimer_tg_show(struct kobject *kobj, struct attribute *attr, mutex_unlock(&list_mutex); - if (time_after(expires, jiffies)) + if (time_after(expires, now)) return sprintf(buf, "%u\n", - jiffies_to_msecs(expires - jiffies) / 1000); + jiffies_to_msecs(expires - now) / 1000); - return sprintf(buf, "0\n"); + if (timer->send_nl_msg) + return sprintf(buf, "0 %d\n", + jiffies_to_msecs(now - expires) / 1000); + else + return sprintf(buf, "0\n"); } static void idletimer_tg_work(struct work_struct *work) @@ -105,6 +141,9 @@ static void idletimer_tg_work(struct work_struct *work) work); sysfs_notify(idletimer_tg_kobj, NULL, timer->attr.attr.name); + + if (timer->send_nl_msg) + notify_netlink_uevent(timer->attr.attr.name, timer); } static void idletimer_tg_expired(unsigned long data) @@ -113,6 +152,7 @@ static void idletimer_tg_expired(unsigned long data) pr_debug("timer %s expired\n", timer->attr.attr.name); + timer->active = false; schedule_work(&timer->work); } @@ -146,6 +186,8 @@ static int idletimer_tg_create(struct idletimer_tg_info *info) setup_timer(&info->timer->timer, idletimer_tg_expired, (unsigned long) info->timer); info->timer->refcnt = 1; + info->timer->send_nl_msg = (info->send_nl_msg == 0) ? false : true; + info->timer->active = true; mod_timer(&info->timer->timer, msecs_to_jiffies(info->timeout * 1000) + jiffies); @@ -169,14 +211,24 @@ static unsigned int idletimer_tg_target(struct sk_buff *skb, const struct xt_action_param *par) { const struct idletimer_tg_info *info = par->targinfo; + unsigned long now = jiffies; pr_debug("resetting timer %s, timeout period %u\n", info->label, info->timeout); BUG_ON(!info->timer); + info->timer->active = true; + + if (time_before(info->timer->timer.expires, now)) { + schedule_work(&info->timer->work); + pr_debug("Starting timer %s (Expired, Jiffies): %lu, %lu\n", + info->label, info->timer->timer.expires, now); + } + + /* TODO: Avoid modifying timers on each packet */ mod_timer(&info->timer->timer, - msecs_to_jiffies(info->timeout * 1000) + jiffies); + msecs_to_jiffies(info->timeout * 1000) + now); return XT_CONTINUE; } @@ -185,8 +237,9 @@ static int idletimer_tg_checkentry(const struct xt_tgchk_param *par) { struct idletimer_tg_info *info = par->targinfo; int ret; + unsigned long now = jiffies; - pr_debug("checkentry targinfo%s\n", info->label); + pr_debug("checkentry targinfo %s\n", info->label); if (info->timeout == 0) { pr_debug("timeout value is zero\n"); @@ -205,8 +258,16 @@ static int idletimer_tg_checkentry(const struct xt_tgchk_param *par) info->timer = __idletimer_tg_find_by_label(info->label); if (info->timer) { info->timer->refcnt++; + info->timer->active = true; + + if (time_before(info->timer->timer.expires, now)) { + schedule_work(&info->timer->work); + pr_debug("Starting Checkentry timer (Expired, Jiffies): %lu, %lu\n", + info->timer->timer.expires, now); + } + mod_timer(&info->timer->timer, - msecs_to_jiffies(info->timeout * 1000) + jiffies); + msecs_to_jiffies(info->timeout * 1000) + now); pr_debug("increased refcnt of timer %s to %u\n", info->label, info->timer->refcnt); @@ -220,6 +281,7 @@ static int idletimer_tg_checkentry(const struct xt_tgchk_param *par) } mutex_unlock(&list_mutex); + return 0; } @@ -241,7 +303,7 @@ static void idletimer_tg_destroy(const struct xt_tgdtor_param *par) kfree(info->timer); } else { pr_debug("decreased refcnt of timer %s to %u\n", - info->label, info->timer->refcnt); + info->label, info->timer->refcnt); } mutex_unlock(&list_mutex); @@ -249,6 +311,7 @@ static void idletimer_tg_destroy(const struct xt_tgdtor_param *par) static struct xt_target idletimer_tg __read_mostly = { .name = "IDLETIMER", + .revision = 1, .family = NFPROTO_UNSPEC, .target = idletimer_tg_target, .targetsize = sizeof(struct idletimer_tg_info), @@ -314,3 +377,4 @@ MODULE_DESCRIPTION("Xtables: idle time monitor"); MODULE_LICENSE("GPL v2"); MODULE_ALIAS("ipt_IDLETIMER"); MODULE_ALIAS("ip6t_IDLETIMER"); +MODULE_ALIAS("arpt_IDLETIMER"); -- 2.20.1