File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
new file mode 100644
index 0000000..1090a52
--- /dev/null
+++ b/net/sched/act_mirred.c
@@ -0,0 +1,284 @@
+/*
+ * net/sched/act_mirred.c packet mirroring and redirect actions
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * Authors: Jamal Hadi Salim (2002-4)
+ *
+ * TODO: Add ingress support (and socket redirect support)
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/skbuff.h>
+#include <linux/rtnetlink.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/gfp.h>
+#include <net/net_namespace.h>
+#include <net/netlink.h>
+#include <net/pkt_sched.h>
+#include <linux/tc_act/tc_mirred.h>
+#include <net/tc_act/tc_mirred.h>
+
+#include <linux/if_arp.h>
+
+#define MIRRED_TAB_MASK 7
+static LIST_HEAD(mirred_list);
+static DEFINE_SPINLOCK(mirred_list_lock);
+
+static void tcf_mirred_release(struct tc_action *a, int bind)
+{
+ struct tcf_mirred *m = to_mirred(a);
+ struct net_device *dev;
+
+ /* We could be called either in a RCU callback or with RTNL lock held. */
+ spin_lock_bh(&mirred_list_lock);
+ list_del(&m->tcfm_list);
+ dev = rcu_dereference_protected(m->tcfm_dev, 1);
+ if (dev)
+ dev_put(dev);
+ spin_unlock_bh(&mirred_list_lock);
+}
+
+static const struct nla_policy mirred_policy[TCA_MIRRED_MAX + 1] = {
+ [TCA_MIRRED_PARMS] = { .len = sizeof(struct tc_mirred) },
+};
+
+static int tcf_mirred_init(struct net *net, struct nlattr *nla,
+ struct nlattr *est, struct tc_action *a, int ovr,
+ int bind)
+{
+ struct nlattr *tb[TCA_MIRRED_MAX + 1];
+ struct tc_mirred *parm;
+ struct tcf_mirred *m;
+ struct net_device *dev;
+ int ret, ok_push = 0;
+
+ if (nla == NULL)
+ return -EINVAL;
+ ret = nla_parse_nested(tb, TCA_MIRRED_MAX, nla, mirred_policy);
+ if (ret < 0)
+ return ret;
+ if (tb[TCA_MIRRED_PARMS] == NULL)
+ return -EINVAL;
+ parm = nla_data(tb[TCA_MIRRED_PARMS]);
+ switch (parm->eaction) {
+ case TCA_EGRESS_MIRROR:
+ case TCA_EGRESS_REDIR:
+ break;
+ default:
+ return -EINVAL;
+ }
+ if (parm->ifindex) {
+ dev = __dev_get_by_index(net, parm->ifindex);
+ if (dev == NULL)
+ return -ENODEV;
+ switch (dev->type) {
+ case ARPHRD_TUNNEL:
+ case ARPHRD_TUNNEL6:
+ case ARPHRD_SIT:
+ case ARPHRD_IPGRE:
+ case ARPHRD_VOID:
+ case ARPHRD_NONE:
+ ok_push = 0;
+ break;
+ default:
+ ok_push = 1;
+ break;
+ }
+ } else {
+ dev = NULL;
+ }
+
+ if (!tcf_hash_check(parm->index, a, bind)) {
+ if (dev == NULL)
+ return -EINVAL;
+ ret = tcf_hash_create(parm->index, est, a, sizeof(*m),
+ bind, true);
+ if (ret)
+ return ret;
+ ret = ACT_P_CREATED;
+ } else {
+ if (bind)
+ return 0;
+
+ tcf_hash_release(a, bind);
+ if (!ovr)
+ return -EEXIST;
+ }
+ m = to_mirred(a);
+
+ ASSERT_RTNL();
+ m->tcf_action = parm->action;
+ m->tcfm_eaction = parm->eaction;
+ if (dev != NULL) {
+ m->tcfm_ifindex = parm->ifindex;
+ if (ret != ACT_P_CREATED)
+ dev_put(rcu_dereference_protected(m->tcfm_dev, 1));
+ dev_hold(dev);
+ rcu_assign_pointer(m->tcfm_dev, dev);
+ m->tcfm_ok_push = ok_push;
+ }
+
+ if (ret == ACT_P_CREATED) {
+ spin_lock_bh(&mirred_list_lock);
+ list_add(&m->tcfm_list, &mirred_list);
+ spin_unlock_bh(&mirred_list_lock);
+ tcf_hash_insert(a);
+ }
+
+ return ret;
+}
+
+static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a,
+ struct tcf_result *res)
+{
+ struct tcf_mirred *m = a->priv;
+ struct net_device *dev;
+ struct sk_buff *skb2;
+ int retval, err;
+ u32 at;
+
+ tcf_lastuse_update(&m->tcf_tm);
+
+ bstats_cpu_update(this_cpu_ptr(m->common.cpu_bstats), skb);
+
+ rcu_read_lock();
+ retval = READ_ONCE(m->tcf_action);
+ dev = rcu_dereference(m->tcfm_dev);
+ if (unlikely(!dev)) {
+ pr_notice_once("tc mirred: target device is gone\n");
+ goto out;
+ }
+
+ if (unlikely(!(dev->flags & IFF_UP))) {
+ net_notice_ratelimited("tc mirred to Houston: device %s is down\n",
+ dev->name);
+ goto out;
+ }
+
+ at = G_TC_AT(skb->tc_verd);
+ skb2 = skb_clone(skb, GFP_ATOMIC);
+ if (!skb2)
+ goto out;
+
+ if (!(at & AT_EGRESS)) {
+ if (m->tcfm_ok_push)
+ skb_push_rcsum(skb2, skb->mac_len);
+ }
+
+ /* mirror is always swallowed */
+ if (m->tcfm_eaction != TCA_EGRESS_MIRROR)
+ skb2->tc_verd = SET_TC_FROM(skb2->tc_verd, at);
+
+ skb2->skb_iif = skb->dev->ifindex;
+ skb2->dev = dev;
+ skb_sender_cpu_clear(skb2);
+ err = dev_queue_xmit(skb2);
+
+ if (err) {
+out:
+ qstats_overlimit_inc(this_cpu_ptr(m->common.cpu_qstats));
+ if (m->tcfm_eaction != TCA_EGRESS_MIRROR)
+ retval = TC_ACT_SHOT;
+ }
+ rcu_read_unlock();
+
+ return retval;
+}
+
+static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
+{
+ unsigned char *b = skb_tail_pointer(skb);
+ struct tcf_mirred *m = a->priv;
+ struct tc_mirred opt = {
+ .index = m->tcf_index,
+ .action = m->tcf_action,
+ .refcnt = m->tcf_refcnt - ref,
+ .bindcnt = m->tcf_bindcnt - bind,
+ .eaction = m->tcfm_eaction,
+ .ifindex = m->tcfm_ifindex,
+ };
+ struct tcf_t t;
+
+ if (nla_put(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt))
+ goto nla_put_failure;
+ t.install = jiffies_to_clock_t(jiffies - m->tcf_tm.install);
+ t.lastuse = jiffies_to_clock_t(jiffies - m->tcf_tm.lastuse);
+ t.expires = jiffies_to_clock_t(m->tcf_tm.expires);
+ if (nla_put(skb, TCA_MIRRED_TM, sizeof(t), &t))
+ goto nla_put_failure;
+ return skb->len;
+
+nla_put_failure:
+ nlmsg_trim(skb, b);
+ return -1;
+}
+
+static int mirred_device_event(struct notifier_block *unused,
+ unsigned long event, void *ptr)
+{
+ struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+ struct tcf_mirred *m;
+
+ ASSERT_RTNL();
+ if (event == NETDEV_UNREGISTER) {
+ spin_lock_bh(&mirred_list_lock);
+ list_for_each_entry(m, &mirred_list, tcfm_list) {
+ if (rcu_access_pointer(m->tcfm_dev) == dev) {
+ dev_put(dev);
+ /* Note : no rcu grace period necessary, as
+ * net_device are already rcu protected.
+ */
+ RCU_INIT_POINTER(m->tcfm_dev, NULL);
+ }
+ }
+ spin_unlock_bh(&mirred_list_lock);
+ }
+
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block mirred_device_notifier = {
+ .notifier_call = mirred_device_event,
+};
+
+static struct tc_action_ops act_mirred_ops = {
+ .kind = "mirred",
+ .type = TCA_ACT_MIRRED,
+ .owner = THIS_MODULE,
+ .act = tcf_mirred,
+ .dump = tcf_mirred_dump,
+ .cleanup = tcf_mirred_release,
+ .init = tcf_mirred_init,
+};
+
+MODULE_AUTHOR("Jamal Hadi Salim(2002)");
+MODULE_DESCRIPTION("Device Mirror/redirect actions");
+MODULE_LICENSE("GPL");
+
+static int __init mirred_init_module(void)
+{
+ int err = register_netdevice_notifier(&mirred_device_notifier);
+ if (err)
+ return err;
+
+ pr_info("Mirror/redirect action on\n");
+ return tcf_register_action(&act_mirred_ops, MIRRED_TAB_MASK);
+}
+
+static void __exit mirred_cleanup_module(void)
+{
+ tcf_unregister_action(&act_mirred_ops);
+ unregister_netdevice_notifier(&mirred_device_notifier);
+}
+
+module_init(mirred_init_module);
+module_exit(mirred_cleanup_module);