diff options
Diffstat (limited to 'net/sched/act_mirred.c')
| -rw-r--r-- | net/sched/act_mirred.c | 259 |
1 files changed, 259 insertions, 0 deletions
diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c new file mode 100644 index 0000000..70341c0 --- /dev/null +++ b/net/sched/act_mirred.c @@ -0,0 +1,259 @@ +/* + * net/sched/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 <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 struct tcf_common *tcf_mirred_ht[MIRRED_TAB_MASK + 1]; +static u32 mirred_idx_gen; +static DEFINE_RWLOCK(mirred_lock); + +static struct tcf_hashinfo mirred_hash_info = { + .htab = tcf_mirred_ht, + .hmask = MIRRED_TAB_MASK, + .lock = &mirred_lock, +}; + +static inline int tcf_mirred_release(struct tcf_mirred *m, int bind) +{ + if (m) { + if (bind) + m->tcf_bindcnt--; + m->tcf_refcnt--; + if(!m->tcf_bindcnt && m->tcf_refcnt <= 0) { + dev_put(m->tcfm_dev); + tcf_hash_destroy(&m->common, &mirred_hash_info); + return 1; + } + } + return 0; +} + +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 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 tcf_common *pc; + struct net_device *dev = NULL; + int ret = 0, err; + int ok_push = 0; + + if (nla == NULL) + return -EINVAL; + + err = nla_parse_nested(tb, TCA_MIRRED_MAX, nla, mirred_policy); + if (err < 0) + return err; + + if (tb[TCA_MIRRED_PARMS] == NULL) + return -EINVAL; + parm = nla_data(tb[TCA_MIRRED_PARMS]); + + if (parm->ifindex) { + dev = __dev_get_by_index(&init_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; + } + } + + pc = tcf_hash_check(parm->index, a, bind, &mirred_hash_info); + if (!pc) { + if (!parm->ifindex) + return -EINVAL; + pc = tcf_hash_create(parm->index, est, a, sizeof(*m), bind, + &mirred_idx_gen, &mirred_hash_info); + if (unlikely(!pc)) + return -ENOMEM; + ret = ACT_P_CREATED; + } else { + if (!ovr) { + tcf_mirred_release(to_mirred(pc), bind); + return -EEXIST; + } + } + m = to_mirred(pc); + + spin_lock_bh(&m->tcf_lock); + m->tcf_action = parm->action; + m->tcfm_eaction = parm->eaction; + if (parm->ifindex) { + m->tcfm_ifindex = parm->ifindex; + if (ret != ACT_P_CREATED) + dev_put(m->tcfm_dev); + m->tcfm_dev = dev; + dev_hold(dev); + m->tcfm_ok_push = ok_push; + } + spin_unlock_bh(&m->tcf_lock); + if (ret == ACT_P_CREATED) + tcf_hash_insert(pc, &mirred_hash_info); + + return ret; +} + +static int tcf_mirred_cleanup(struct tc_action *a, int bind) +{ + struct tcf_mirred *m = a->priv; + + if (m) + return tcf_mirred_release(m, bind); + return 0; +} + +static int tcf_mirred(struct sk_buff *skb, struct tc_action *a, + struct tcf_result *res) +{ + struct tcf_mirred *m = a->priv; + struct net_device *dev; + struct sk_buff *skb2 = NULL; + u32 at = G_TC_AT(skb->tc_verd); + + spin_lock(&m->tcf_lock); + + dev = m->tcfm_dev; + m->tcf_tm.lastuse = jiffies; + + if (!(dev->flags&IFF_UP) ) { + if (net_ratelimit()) + printk("mirred to Houston: device %s is gone!\n", + dev->name); +bad_mirred: + if (skb2 != NULL) + kfree_skb(skb2); + m->tcf_qstats.overlimits++; + m->tcf_bstats.bytes += qdisc_pkt_len(skb); + m->tcf_bstats.packets++; + spin_unlock(&m->tcf_lock); + /* should we be asking for packet to be dropped? + * may make sense for redirect case only + */ + return TC_ACT_SHOT; + } + + skb2 = skb_act_clone(skb, GFP_ATOMIC); + if (skb2 == NULL) + goto bad_mirred; + if (m->tcfm_eaction != TCA_EGRESS_MIRROR && + m->tcfm_eaction != TCA_EGRESS_REDIR) { + if (net_ratelimit()) + printk("tcf_mirred unknown action %d\n", + m->tcfm_eaction); + goto bad_mirred; + } + + m->tcf_bstats.bytes += qdisc_pkt_len(skb2); + m->tcf_bstats.packets++; + if (!(at & AT_EGRESS)) + if (m->tcfm_ok_push) + skb_push(skb2, skb2->dev->hard_header_len); + + /* mirror is always swallowed */ + if (m->tcfm_eaction != TCA_EGRESS_MIRROR) + skb2->tc_verd = SET_TC_FROM(skb2->tc_verd, at); + + skb2->dev = dev; + skb2->iif = skb->dev->ifindex; + dev_queue_xmit(skb2); + spin_unlock(&m->tcf_lock); + return m->tcf_action; +} + +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; + struct tcf_t t; + + opt.index = m->tcf_index; + opt.action = m->tcf_action; + opt.refcnt = m->tcf_refcnt - ref; + opt.bindcnt = m->tcf_bindcnt - bind; + opt.eaction = m->tcfm_eaction; + opt.ifindex = m->tcfm_ifindex; + NLA_PUT(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt); + 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); + NLA_PUT(skb, TCA_MIRRED_TM, sizeof(t), &t); + return skb->len; + +nla_put_failure: + nlmsg_trim(skb, b); + return -1; +} + +static struct tc_action_ops act_mirred_ops = { + .kind = "mirred", + .hinfo = &mirred_hash_info, + .type = TCA_ACT_MIRRED, + .capab = TCA_CAP_NONE, + .owner = THIS_MODULE, + .act = tcf_mirred, + .dump = tcf_mirred_dump, + .cleanup = tcf_mirred_cleanup, + .lookup = tcf_hash_search, + .init = tcf_mirred_init, + .walk = tcf_generic_walker +}; + +MODULE_AUTHOR("Jamal Hadi Salim(2002)"); +MODULE_DESCRIPTION("Device Mirror/redirect actions"); +MODULE_LICENSE("GPL"); + +static int __init mirred_init_module(void) +{ + printk("Mirror/redirect action on\n"); + return tcf_register_action(&act_mirred_ops); +} + +static void __exit mirred_cleanup_module(void) +{ + tcf_unregister_action(&act_mirred_ops); +} + +module_init(mirred_init_module); +module_exit(mirred_cleanup_module); |
