diff options
Diffstat (limited to 'net/sched/act_mirred.c')
| -rw-r--r-- | net/sched/act_mirred.c | 267 |
1 files changed, 267 insertions, 0 deletions
diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c new file mode 100644 index 000000000..3f63ceac8 --- /dev/null +++ b/net/sched/act_mirred.c @@ -0,0 +1,267 @@ +/* + * 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 void tcf_mirred_release(struct tc_action *a, int bind) +{ + struct tcf_mirred *m = to_mirred(a); + list_del(&m->tcfm_list); + if (m->tcfm_dev) + dev_put(m->tcfm_dev); +} + +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); + if (ret) + return ret; + ret = ACT_P_CREATED; + } else { + if (!ovr) { + tcf_hash_release(a, bind); + return -EEXIST; + } + } + m = to_mirred(a); + + spin_lock_bh(&m->tcf_lock); + 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(m->tcfm_dev); + dev_hold(dev); + m->tcfm_dev = dev; + m->tcfm_ok_push = ok_push; + } + spin_unlock_bh(&m->tcf_lock); + if (ret == ACT_P_CREATED) { + list_add(&m->tcfm_list, &mirred_list); + 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; + u32 at; + int retval, err = 1; + + spin_lock(&m->tcf_lock); + m->tcf_tm.lastuse = jiffies; + bstats_update(&m->tcf_bstats, skb); + + dev = m->tcfm_dev; + if (!dev) { + printk_once(KERN_NOTICE "tc mirred: target device is gone\n"); + goto out; + } + + if (!(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_act_clone(skb, GFP_ATOMIC, m->tcf_action); + if (skb2 == NULL) + goto out; + + if (!(at & AT_EGRESS)) { + if (m->tcfm_ok_push) + skb_push(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; + err = dev_queue_xmit(skb2); + +out: + if (err) { + m->tcf_qstats.overlimits++; + if (m->tcfm_eaction != TCA_EGRESS_MIRROR) + retval = TC_ACT_SHOT; + else + retval = m->tcf_action; + } else + retval = m->tcf_action; + spin_unlock(&m->tcf_lock); + + 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; + + if (event == NETDEV_UNREGISTER) + list_for_each_entry(m, &mirred_list, tcfm_list) { + spin_lock_bh(&m->tcf_lock); + if (m->tcfm_dev == dev) { + dev_put(dev); + m->tcfm_dev = NULL; + } + spin_unlock_bh(&m->tcf_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); |