diff options
Diffstat (limited to 'net/netfilter/xt_IDLETIMER.c')
-rw-r--r-- | net/netfilter/xt_IDLETIMER.c | 247 |
1 files changed, 236 insertions, 11 deletions
diff --git a/net/netfilter/xt_IDLETIMER.c b/net/netfilter/xt_IDLETIMER.c index f407ebc13481..ddf77f7fbe24 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 <ext-timo.teras@nokia.com> * * Converted to x_tables and reworked for upstream inclusion @@ -38,8 +39,16 @@ #include <linux/netfilter/xt_IDLETIMER.h> #include <linux/kdev_t.h> #include <linux/kobject.h> +#include <linux/skbuff.h> #include <linux/workqueue.h> #include <linux/sysfs.h> +#include <linux/rtc.h> +#include <linux/time.h> +#include <linux/math64.h> +#include <linux/suspend.h> +#include <linux/notifier.h> +#include <net/net_namespace.h> +#include <net/sock.h> struct idletimer_tg_attr { struct attribute attr; @@ -55,14 +64,110 @@ struct idletimer_tg { struct kobject *kobj; struct idletimer_tg_attr attr; + struct timespec delayed_timer_trigger; + struct timespec last_modified_timer; + struct timespec last_suspend_time; + struct notifier_block pm_nb; + + int timeout; unsigned int refcnt; + bool work_pending; + bool send_nl_msg; + bool active; + uid_t uid; }; static LIST_HEAD(idletimer_tg_list); static DEFINE_MUTEX(list_mutex); +static DEFINE_SPINLOCK(timestamp_lock); static struct kobject *idletimer_tg_kobj; +static bool check_for_delayed_trigger(struct idletimer_tg *timer, + struct timespec *ts) +{ + bool state; + struct timespec temp; + spin_lock_bh(×tamp_lock); + timer->work_pending = false; + if ((ts->tv_sec - timer->last_modified_timer.tv_sec) > timer->timeout || + timer->delayed_timer_trigger.tv_sec != 0) { + state = false; + temp.tv_sec = timer->timeout; + temp.tv_nsec = 0; + if (timer->delayed_timer_trigger.tv_sec != 0) { + temp = timespec_add(timer->delayed_timer_trigger, temp); + ts->tv_sec = temp.tv_sec; + ts->tv_nsec = temp.tv_nsec; + timer->delayed_timer_trigger.tv_sec = 0; + timer->work_pending = true; + schedule_work(&timer->work); + } else { + temp = timespec_add(timer->last_modified_timer, temp); + ts->tv_sec = temp.tv_sec; + ts->tv_nsec = temp.tv_nsec; + } + } else { + state = timer->active; + } + spin_unlock_bh(×tamp_lock); + return state; +} + +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 timestamp_msg[NLMSG_MAX_SIZE]; + char uid_msg[NLMSG_MAX_SIZE]; + char *envp[] = { iface_msg, state_msg, timestamp_msg, uid_msg, NULL }; + int res; + struct timespec ts; + uint64_t time_ns; + bool state; + + res = snprintf(iface_msg, NLMSG_MAX_SIZE, "INTERFACE=%s", + iface); + if (NLMSG_MAX_SIZE <= res) { + pr_err("message too long (%d)", res); + return; + } + + get_monotonic_boottime(&ts); + state = check_for_delayed_trigger(timer, &ts); + res = snprintf(state_msg, NLMSG_MAX_SIZE, "STATE=%s", + state ? "active" : "inactive"); + + if (NLMSG_MAX_SIZE <= res) { + pr_err("message too long (%d)", res); + return; + } + + if (state) { + res = snprintf(uid_msg, NLMSG_MAX_SIZE, "UID=%u", timer->uid); + if (NLMSG_MAX_SIZE <= res) + pr_err("message too long (%d)", res); + } else { + res = snprintf(uid_msg, NLMSG_MAX_SIZE, "UID="); + if (NLMSG_MAX_SIZE <= res) + pr_err("message too long (%d)", res); + } + + time_ns = timespec_to_ns(&ts); + res = snprintf(timestamp_msg, NLMSG_MAX_SIZE, "TIME_NS=%llu", time_ns); + if (NLMSG_MAX_SIZE <= res) { + timestamp_msg[0] = '\0'; + pr_err("message too long (%d)", res); + } + + pr_debug("putting nlmsg: <%s> <%s> <%s> <%s>\n", iface_msg, state_msg, + timestamp_msg, uid_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 +188,7 @@ 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 +198,15 @@ 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 +215,9 @@ 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) @@ -112,8 +225,55 @@ static void idletimer_tg_expired(unsigned long data) struct idletimer_tg *timer = (struct idletimer_tg *) data; pr_debug("timer %s expired\n", timer->attr.attr.name); - + spin_lock_bh(×tamp_lock); + timer->active = false; + timer->work_pending = true; schedule_work(&timer->work); + spin_unlock_bh(×tamp_lock); +} + +static int idletimer_resume(struct notifier_block *notifier, + unsigned long pm_event, void *unused) +{ + struct timespec ts; + unsigned long time_diff, now = jiffies; + struct idletimer_tg *timer = container_of(notifier, + struct idletimer_tg, pm_nb); + if (!timer) + return NOTIFY_DONE; + switch (pm_event) { + case PM_SUSPEND_PREPARE: + get_monotonic_boottime(&timer->last_suspend_time); + break; + case PM_POST_SUSPEND: + spin_lock_bh(×tamp_lock); + if (!timer->active) { + spin_unlock_bh(×tamp_lock); + break; + } + /* since jiffies are not updated when suspended now represents + * the time it would have suspended */ + if (time_after(timer->timer.expires, now)) { + get_monotonic_boottime(&ts); + ts = timespec_sub(ts, timer->last_suspend_time); + time_diff = timespec_to_jiffies(&ts); + if (timer->timer.expires > (time_diff + now)) { + mod_timer_pending(&timer->timer, + (timer->timer.expires - time_diff)); + } else { + del_timer(&timer->timer); + timer->timer.expires = 0; + timer->active = false; + timer->work_pending = true; + schedule_work(&timer->work); + } + } + spin_unlock_bh(×tamp_lock); + break; + default: + break; + } + return NOTIFY_DONE; } static int idletimer_tg_create(struct idletimer_tg_info *info) @@ -145,6 +305,21 @@ 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; + info->timer->timeout = info->timeout; + + info->timer->delayed_timer_trigger.tv_sec = 0; + info->timer->delayed_timer_trigger.tv_nsec = 0; + info->timer->work_pending = false; + info->timer->uid = 0; + get_monotonic_boottime(&info->timer->last_modified_timer); + + info->timer->pm_nb.notifier_call = idletimer_resume; + ret = register_pm_notifier(&info->timer->pm_nb); + if (ret) + printk(KERN_WARNING "[%s] Failed to register pm notifier %d\n", + __func__, ret); mod_timer(&info->timer->timer, msecs_to_jiffies(info->timeout * 1000) + jiffies); @@ -161,6 +336,46 @@ out: return ret; } +static void reset_timer(const struct idletimer_tg_info *info, + struct sk_buff *skb) +{ + unsigned long now = jiffies; + struct idletimer_tg *timer = info->timer; + bool timer_prev; + + spin_lock_bh(×tamp_lock); + timer_prev = timer->active; + timer->active = true; + /* timer_prev is used to guard overflow problem in time_before*/ + if (!timer_prev || time_before(timer->timer.expires, now)) { + pr_debug("Starting Checkentry timer (Expired, Jiffies): %lu, %lu\n", + timer->timer.expires, now); + + /* Stores the uid resposible for waking up the radio */ + if (skb && (skb->sk)) { + struct sock *sk = skb->sk; + read_lock_bh(&sk->sk_callback_lock); + if ((sk->sk_socket) && (sk->sk_socket->file) && + (sk->sk_socket->file->f_cred)) + timer->uid = sk->sk_socket->file->f_cred->uid; + read_unlock_bh(&sk->sk_callback_lock); + } + + /* checks if there is a pending inactive notification*/ + if (timer->work_pending) + timer->delayed_timer_trigger = timer->last_modified_timer; + else { + timer->work_pending = true; + schedule_work(&timer->work); + } + } + + get_monotonic_boottime(&timer->last_modified_timer); + mod_timer(&timer->timer, + msecs_to_jiffies(info->timeout * 1000) + now); + spin_unlock_bh(×tamp_lock); +} + /* * The actual xt_tables plugin. */ @@ -168,15 +383,23 @@ 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); - mod_timer(&info->timer->timer, - msecs_to_jiffies(info->timeout * 1000) + jiffies); + 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 */ + reset_timer(info, skb); return XT_CONTINUE; } @@ -185,7 +408,7 @@ static int idletimer_tg_checkentry(const struct xt_tgchk_param *par) struct idletimer_tg_info *info = par->targinfo; int ret; - 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"); @@ -204,9 +427,7 @@ 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++; - mod_timer(&info->timer->timer, - msecs_to_jiffies(info->timeout * 1000) + jiffies); - + reset_timer(info, NULL); pr_debug("increased refcnt of timer %s to %u\n", info->label, info->timer->refcnt); } else { @@ -219,6 +440,7 @@ static int idletimer_tg_checkentry(const struct xt_tgchk_param *par) } mutex_unlock(&list_mutex); + return 0; } @@ -236,11 +458,12 @@ static void idletimer_tg_destroy(const struct xt_tgdtor_param *par) list_del(&info->timer->entry); del_timer_sync(&info->timer->timer); sysfs_remove_file(idletimer_tg_kobj, &info->timer->attr.attr); + unregister_pm_notifier(&info->timer->pm_nb); kfree(info->timer->attr.attr.name); 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); @@ -248,6 +471,7 @@ 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), @@ -313,3 +537,4 @@ MODULE_DESCRIPTION("Xtables: idle time monitor"); MODULE_LICENSE("GPL v2"); MODULE_ALIAS("ipt_IDLETIMER"); MODULE_ALIAS("ip6t_IDLETIMER"); +MODULE_ALIAS("arpt_IDLETIMER"); |