/* * 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 <asm/uaccess.h> #include <asm/system.h> #include <asm/bitops.h> #include <linux/config.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/sched.h> #include <linux/string.h> #include <linux/mm.h> #include <linux/socket.h> #include <linux/sockios.h> #include <linux/in.h> #include <linux/errno.h> #include <linux/interrupt.h> #include <linux/netdevice.h> #include <linux/skbuff.h> #include <linux/rtnetlink.h> #include <linux/module.h> #include <linux/init.h> #include <linux/proc_fs.h> #include <net/sock.h> #include <net/pkt_sched.h> #include <linux/tc_act/tc_mirred.h> #include <net/tc_act/tc_mirred.h> #include <linux/etherdevice.h> #include <linux/if_arp.h> /* use generic hash table */ #define MY_TAB_SIZE 8 #define MY_TAB_MASK (MY_TAB_SIZE - 1) static u32 idx_gen; static struct tcf_mirred *tcf_mirred_ht[MY_TAB_SIZE]; static DEFINE_RWLOCK(mirred_lock); /* ovewrride the defaults */ #define tcf_st tcf_mirred #define tc_st tc_mirred #define tcf_t_lock mirred_lock #define tcf_ht tcf_mirred_ht #define CONFIG_NET_ACT_INIT 1 #include <net/pkt_act.h> static inline int tcf_mirred_release(struct tcf_mirred *p, int bind) { if (p) { if (bind) p->bindcnt--; p->refcnt--; if(!p->bindcnt && p->refcnt <= 0) { dev_put(p->dev); tcf_hash_destroy(p); return 1; } } return 0; } static int tcf_mirred_init(struct rtattr *rta, struct rtattr *est, struct tc_action *a, int ovr, int bind) { struct rtattr *tb[TCA_MIRRED_MAX]; struct tc_mirred *parm; struct tcf_mirred *p; struct net_device *dev = NULL; int ret = 0; int ok_push = 0; if (rta == NULL || rtattr_parse_nested(tb, TCA_MIRRED_MAX, rta) < 0) return -EINVAL; if (tb[TCA_MIRRED_PARMS-1] == NULL || RTA_PAYLOAD(tb[TCA_MIRRED_PARMS-1]) < sizeof(*parm)) return -EINVAL; parm = RTA_DATA(tb[TCA_MIRRED_PARMS-1]); if (parm->ifindex) { dev = __dev_get_by_index(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; } } p = tcf_hash_check(parm->index, a, ovr, bind); if (p == NULL) { if (!parm->ifindex) return -EINVAL; p = tcf_hash_create(parm->index, est, a, sizeof(*p), ovr, bind); if (p == NULL) return -ENOMEM; ret = ACT_P_CREATED; } else { if (!ovr) { tcf_mirred_release(p, bind); return -EEXIST; } } spin_lock_bh(&p->lock); p->action = parm->action; p->eaction = parm->eaction; if (parm->ifindex) { p->ifindex = parm->ifindex; if (ret != ACT_P_CREATED) dev_put(p->dev); p->dev = dev; dev_hold(dev); p->ok_push = ok_push; } spin_unlock_bh(&p->lock); if (ret == ACT_P_CREATED) tcf_hash_insert(p); DPRINTK("tcf_mirred_init index %d action %d eaction %d device %s " "ifindex %d\n", parm->index, parm->action, parm->eaction, dev->name, parm->ifindex); return ret; } static int tcf_mirred_cleanup(struct tc_action *a, int bind) { struct tcf_mirred *p = PRIV(a, mirred); if (p != NULL) return tcf_mirred_release(p, bind); return 0; } static int tcf_mirred(struct sk_buff *skb, struct tc_action *a, struct tcf_result *res) { struct tcf_mirred *p = PRIV(a, mirred); struct net_device *dev; struct sk_buff *skb2 = NULL; u32 at = G_TC_AT(skb->tc_verd); spin_lock(&p->lock); dev = p->dev; p->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); p->qstats.overlimits++; p->bstats.bytes += skb->len; p->bstats.packets++; spin_unlock(&p->lock); /* should we be asking for packet to be dropped? * may make sense for redirect case only */ return TC_ACT_SHOT; } skb2 = skb_clone(skb, GFP_ATOMIC); if (skb2 == NULL) goto bad_mirred; if (p->eaction != TCA_EGRESS_MIRROR && p->eaction != TCA_EGRESS_REDIR) { if (net_ratelimit()) printk("tcf_mirred unknown action %d\n", p->eaction); goto bad_mirred; } p->bstats.bytes += skb2->len; p->bstats.packets++; if (!(at & AT_EGRESS)) if (p->ok_push) skb_push(skb2, skb2->dev->hard_header_len); /* mirror is always swallowed */ if (p->eaction != TCA_EGRESS_MIRROR) skb2->tc_verd = SET_TC_FROM(skb2->tc_verd, at); skb2->dev = dev; skb2->input_dev = skb->dev; dev_queue_xmit(skb2); spin_unlock(&p->lock); return p->action; } static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref) { unsigned char *b = skb->tail; struct tc_mirred opt; struct tcf_mirred *p = PRIV(a, mirred); struct tcf_t t; opt.index = p->index; opt.action = p->action; opt.refcnt = p->refcnt - ref; opt.bindcnt = p->bindcnt - bind; opt.eaction = p->eaction; opt.ifindex = p->ifindex; DPRINTK("tcf_mirred_dump index %d action %d eaction %d ifindex %d\n", p->index, p->action, p->eaction, p->ifindex); RTA_PUT(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt); t.install = jiffies_to_clock_t(jiffies - p->tm.install); t.lastuse = jiffies_to_clock_t(jiffies - p->tm.lastuse); t.expires = jiffies_to_clock_t(p->tm.expires); RTA_PUT(skb, TCA_MIRRED_TM, sizeof(t), &t); return skb->len; rtattr_failure: skb_trim(skb, b - skb->data); return -1; } static struct tc_action_ops act_mirred_ops = { .kind = "mirred", .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);