| /* | 
 |  * net/sched/act_ipt.c		iptables target interface | 
 |  * | 
 |  *TODO: Add other tables. For now we only support the ipv4 table targets | 
 |  * | 
 |  *		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. | 
 |  * | 
 |  * Copyright:	Jamal Hadi Salim (2002-13) | 
 |  */ | 
 |  | 
 | #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/slab.h> | 
 | #include <net/netlink.h> | 
 | #include <net/pkt_sched.h> | 
 | #include <linux/tc_act/tc_ipt.h> | 
 | #include <net/tc_act/tc_ipt.h> | 
 |  | 
 | #include <linux/netfilter_ipv4/ip_tables.h> | 
 |  | 
 |  | 
 | #define IPT_TAB_MASK     15 | 
 |  | 
 | static unsigned int ipt_net_id; | 
 | static struct tc_action_ops act_ipt_ops; | 
 |  | 
 | static unsigned int xt_net_id; | 
 | static struct tc_action_ops act_xt_ops; | 
 |  | 
 | static int ipt_init_target(struct net *net, struct xt_entry_target *t, | 
 | 			   char *table, unsigned int hook) | 
 | { | 
 | 	struct xt_tgchk_param par; | 
 | 	struct xt_target *target; | 
 | 	struct ipt_entry e = {}; | 
 | 	int ret = 0; | 
 |  | 
 | 	target = xt_request_find_target(AF_INET, t->u.user.name, | 
 | 					t->u.user.revision); | 
 | 	if (IS_ERR(target)) | 
 | 		return PTR_ERR(target); | 
 |  | 
 | 	t->u.kernel.target = target; | 
 | 	memset(&par, 0, sizeof(par)); | 
 | 	par.net       = net; | 
 | 	par.table     = table; | 
 | 	par.entryinfo = &e; | 
 | 	par.target    = target; | 
 | 	par.targinfo  = t->data; | 
 | 	par.hook_mask = hook; | 
 | 	par.family    = NFPROTO_IPV4; | 
 |  | 
 | 	ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false); | 
 | 	if (ret < 0) { | 
 | 		module_put(t->u.kernel.target->me); | 
 | 		return ret; | 
 | 	} | 
 | 	return 0; | 
 | } | 
 |  | 
 | static void ipt_destroy_target(struct xt_entry_target *t) | 
 | { | 
 | 	struct xt_tgdtor_param par = { | 
 | 		.target   = t->u.kernel.target, | 
 | 		.targinfo = t->data, | 
 | 		.family   = NFPROTO_IPV4, | 
 | 	}; | 
 | 	if (par.target->destroy != NULL) | 
 | 		par.target->destroy(&par); | 
 | 	module_put(par.target->me); | 
 | } | 
 |  | 
 | static void tcf_ipt_release(struct tc_action *a, int bind) | 
 | { | 
 | 	struct tcf_ipt *ipt = to_ipt(a); | 
 | 	ipt_destroy_target(ipt->tcfi_t); | 
 | 	kfree(ipt->tcfi_tname); | 
 | 	kfree(ipt->tcfi_t); | 
 | } | 
 |  | 
 | static const struct nla_policy ipt_policy[TCA_IPT_MAX + 1] = { | 
 | 	[TCA_IPT_TABLE]	= { .type = NLA_STRING, .len = IFNAMSIZ }, | 
 | 	[TCA_IPT_HOOK]	= { .type = NLA_U32 }, | 
 | 	[TCA_IPT_INDEX]	= { .type = NLA_U32 }, | 
 | 	[TCA_IPT_TARG]	= { .len = sizeof(struct xt_entry_target) }, | 
 | }; | 
 |  | 
 | static int __tcf_ipt_init(struct net *net, unsigned int id, struct nlattr *nla, | 
 | 			  struct nlattr *est, struct tc_action **a, | 
 | 			  const struct tc_action_ops *ops, int ovr, int bind) | 
 | { | 
 | 	struct tc_action_net *tn = net_generic(net, id); | 
 | 	struct nlattr *tb[TCA_IPT_MAX + 1]; | 
 | 	struct tcf_ipt *ipt; | 
 | 	struct xt_entry_target *td, *t; | 
 | 	char *tname; | 
 | 	bool exists = false; | 
 | 	int ret = 0, err; | 
 | 	u32 hook = 0; | 
 | 	u32 index = 0; | 
 |  | 
 | 	if (nla == NULL) | 
 | 		return -EINVAL; | 
 |  | 
 | 	err = nla_parse_nested(tb, TCA_IPT_MAX, nla, ipt_policy, NULL); | 
 | 	if (err < 0) | 
 | 		return err; | 
 |  | 
 | 	if (tb[TCA_IPT_INDEX] != NULL) | 
 | 		index = nla_get_u32(tb[TCA_IPT_INDEX]); | 
 |  | 
 | 	exists = tcf_hash_check(tn, index, a, bind); | 
 | 	if (exists && bind) | 
 | 		return 0; | 
 |  | 
 | 	if (tb[TCA_IPT_HOOK] == NULL || tb[TCA_IPT_TARG] == NULL) { | 
 | 		if (exists) | 
 | 			tcf_hash_release(*a, bind); | 
 | 		return -EINVAL; | 
 | 	} | 
 |  | 
 | 	td = (struct xt_entry_target *)nla_data(tb[TCA_IPT_TARG]); | 
 | 	if (nla_len(tb[TCA_IPT_TARG]) < td->u.target_size) { | 
 | 		if (exists) | 
 | 			tcf_hash_release(*a, bind); | 
 | 		return -EINVAL; | 
 | 	} | 
 |  | 
 | 	if (!exists) { | 
 | 		ret = tcf_hash_create(tn, index, est, a, ops, bind, | 
 | 				      false); | 
 | 		if (ret) | 
 | 			return ret; | 
 | 		ret = ACT_P_CREATED; | 
 | 	} else { | 
 | 		if (bind)/* dont override defaults */ | 
 | 			return 0; | 
 | 		tcf_hash_release(*a, bind); | 
 |  | 
 | 		if (!ovr) | 
 | 			return -EEXIST; | 
 | 	} | 
 | 	hook = nla_get_u32(tb[TCA_IPT_HOOK]); | 
 |  | 
 | 	err = -ENOMEM; | 
 | 	tname = kmalloc(IFNAMSIZ, GFP_KERNEL); | 
 | 	if (unlikely(!tname)) | 
 | 		goto err1; | 
 | 	if (tb[TCA_IPT_TABLE] == NULL || | 
 | 	    nla_strlcpy(tname, tb[TCA_IPT_TABLE], IFNAMSIZ) >= IFNAMSIZ) | 
 | 		strcpy(tname, "mangle"); | 
 |  | 
 | 	t = kmemdup(td, td->u.target_size, GFP_KERNEL); | 
 | 	if (unlikely(!t)) | 
 | 		goto err2; | 
 |  | 
 | 	err = ipt_init_target(net, t, tname, hook); | 
 | 	if (err < 0) | 
 | 		goto err3; | 
 |  | 
 | 	ipt = to_ipt(*a); | 
 |  | 
 | 	spin_lock_bh(&ipt->tcf_lock); | 
 | 	if (ret != ACT_P_CREATED) { | 
 | 		ipt_destroy_target(ipt->tcfi_t); | 
 | 		kfree(ipt->tcfi_tname); | 
 | 		kfree(ipt->tcfi_t); | 
 | 	} | 
 | 	ipt->tcfi_tname = tname; | 
 | 	ipt->tcfi_t     = t; | 
 | 	ipt->tcfi_hook  = hook; | 
 | 	spin_unlock_bh(&ipt->tcf_lock); | 
 | 	if (ret == ACT_P_CREATED) | 
 | 		tcf_hash_insert(tn, *a); | 
 | 	return ret; | 
 |  | 
 | err3: | 
 | 	kfree(t); | 
 | err2: | 
 | 	kfree(tname); | 
 | err1: | 
 | 	if (ret == ACT_P_CREATED) | 
 | 		tcf_hash_cleanup(*a, est); | 
 | 	return err; | 
 | } | 
 |  | 
 | static int tcf_ipt_init(struct net *net, struct nlattr *nla, | 
 | 			struct nlattr *est, struct tc_action **a, int ovr, | 
 | 			int bind) | 
 | { | 
 | 	return __tcf_ipt_init(net, ipt_net_id, nla, est, a, &act_ipt_ops, ovr, | 
 | 			      bind); | 
 | } | 
 |  | 
 | static int tcf_xt_init(struct net *net, struct nlattr *nla, | 
 | 		       struct nlattr *est, struct tc_action **a, int ovr, | 
 | 		       int bind) | 
 | { | 
 | 	return __tcf_ipt_init(net, xt_net_id, nla, est, a, &act_xt_ops, ovr, | 
 | 			      bind); | 
 | } | 
 |  | 
 | static int tcf_ipt(struct sk_buff *skb, const struct tc_action *a, | 
 | 		   struct tcf_result *res) | 
 | { | 
 | 	int ret = 0, result = 0; | 
 | 	struct tcf_ipt *ipt = to_ipt(a); | 
 | 	struct xt_action_param par; | 
 | 	struct nf_hook_state state = { | 
 | 		.net	= dev_net(skb->dev), | 
 | 		.in	= skb->dev, | 
 | 		.hook	= ipt->tcfi_hook, | 
 | 		.pf	= NFPROTO_IPV4, | 
 | 	}; | 
 |  | 
 | 	if (skb_unclone(skb, GFP_ATOMIC)) | 
 | 		return TC_ACT_UNSPEC; | 
 |  | 
 | 	spin_lock(&ipt->tcf_lock); | 
 |  | 
 | 	tcf_lastuse_update(&ipt->tcf_tm); | 
 | 	bstats_update(&ipt->tcf_bstats, skb); | 
 |  | 
 | 	/* yes, we have to worry about both in and out dev | 
 | 	 * worry later - danger - this API seems to have changed | 
 | 	 * from earlier kernels | 
 | 	 */ | 
 | 	par.state    = &state; | 
 | 	par.target   = ipt->tcfi_t->u.kernel.target; | 
 | 	par.targinfo = ipt->tcfi_t->data; | 
 | 	ret = par.target->target(skb, &par); | 
 |  | 
 | 	switch (ret) { | 
 | 	case NF_ACCEPT: | 
 | 		result = TC_ACT_OK; | 
 | 		break; | 
 | 	case NF_DROP: | 
 | 		result = TC_ACT_SHOT; | 
 | 		ipt->tcf_qstats.drops++; | 
 | 		break; | 
 | 	case XT_CONTINUE: | 
 | 		result = TC_ACT_PIPE; | 
 | 		break; | 
 | 	default: | 
 | 		net_notice_ratelimited("tc filter: Bogus netfilter code %d assume ACCEPT\n", | 
 | 				       ret); | 
 | 		result = TC_ACT_OK; | 
 | 		break; | 
 | 	} | 
 | 	spin_unlock(&ipt->tcf_lock); | 
 | 	return result; | 
 |  | 
 | } | 
 |  | 
 | static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, | 
 | 			int ref) | 
 | { | 
 | 	unsigned char *b = skb_tail_pointer(skb); | 
 | 	struct tcf_ipt *ipt = to_ipt(a); | 
 | 	struct xt_entry_target *t; | 
 | 	struct tcf_t tm; | 
 | 	struct tc_cnt c; | 
 |  | 
 | 	/* for simple targets kernel size == user size | 
 | 	 * user name = target name | 
 | 	 * for foolproof you need to not assume this | 
 | 	 */ | 
 |  | 
 | 	t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC); | 
 | 	if (unlikely(!t)) | 
 | 		goto nla_put_failure; | 
 |  | 
 | 	c.bindcnt = ipt->tcf_bindcnt - bind; | 
 | 	c.refcnt = ipt->tcf_refcnt - ref; | 
 | 	strcpy(t->u.user.name, ipt->tcfi_t->u.kernel.target->name); | 
 |  | 
 | 	if (nla_put(skb, TCA_IPT_TARG, ipt->tcfi_t->u.user.target_size, t) || | 
 | 	    nla_put_u32(skb, TCA_IPT_INDEX, ipt->tcf_index) || | 
 | 	    nla_put_u32(skb, TCA_IPT_HOOK, ipt->tcfi_hook) || | 
 | 	    nla_put(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c) || | 
 | 	    nla_put_string(skb, TCA_IPT_TABLE, ipt->tcfi_tname)) | 
 | 		goto nla_put_failure; | 
 |  | 
 | 	tcf_tm_dump(&tm, &ipt->tcf_tm); | 
 | 	if (nla_put_64bit(skb, TCA_IPT_TM, sizeof(tm), &tm, TCA_IPT_PAD)) | 
 | 		goto nla_put_failure; | 
 |  | 
 | 	kfree(t); | 
 | 	return skb->len; | 
 |  | 
 | nla_put_failure: | 
 | 	nlmsg_trim(skb, b); | 
 | 	kfree(t); | 
 | 	return -1; | 
 | } | 
 |  | 
 | static int tcf_ipt_walker(struct net *net, struct sk_buff *skb, | 
 | 			  struct netlink_callback *cb, int type, | 
 | 			  const struct tc_action_ops *ops) | 
 | { | 
 | 	struct tc_action_net *tn = net_generic(net, ipt_net_id); | 
 |  | 
 | 	return tcf_generic_walker(tn, skb, cb, type, ops); | 
 | } | 
 |  | 
 | static int tcf_ipt_search(struct net *net, struct tc_action **a, u32 index) | 
 | { | 
 | 	struct tc_action_net *tn = net_generic(net, ipt_net_id); | 
 |  | 
 | 	return tcf_hash_search(tn, a, index); | 
 | } | 
 |  | 
 | static struct tc_action_ops act_ipt_ops = { | 
 | 	.kind		=	"ipt", | 
 | 	.type		=	TCA_ACT_IPT, | 
 | 	.owner		=	THIS_MODULE, | 
 | 	.act		=	tcf_ipt, | 
 | 	.dump		=	tcf_ipt_dump, | 
 | 	.cleanup	=	tcf_ipt_release, | 
 | 	.init		=	tcf_ipt_init, | 
 | 	.walk		=	tcf_ipt_walker, | 
 | 	.lookup		=	tcf_ipt_search, | 
 | 	.size		=	sizeof(struct tcf_ipt), | 
 | }; | 
 |  | 
 | static __net_init int ipt_init_net(struct net *net) | 
 | { | 
 | 	struct tc_action_net *tn = net_generic(net, ipt_net_id); | 
 |  | 
 | 	return tc_action_net_init(tn, &act_ipt_ops, IPT_TAB_MASK); | 
 | } | 
 |  | 
 | static void __net_exit ipt_exit_net(struct net *net) | 
 | { | 
 | 	struct tc_action_net *tn = net_generic(net, ipt_net_id); | 
 |  | 
 | 	tc_action_net_exit(tn); | 
 | } | 
 |  | 
 | static struct pernet_operations ipt_net_ops = { | 
 | 	.init = ipt_init_net, | 
 | 	.exit = ipt_exit_net, | 
 | 	.id   = &ipt_net_id, | 
 | 	.size = sizeof(struct tc_action_net), | 
 | }; | 
 |  | 
 | static int tcf_xt_walker(struct net *net, struct sk_buff *skb, | 
 | 			 struct netlink_callback *cb, int type, | 
 | 			 const struct tc_action_ops *ops) | 
 | { | 
 | 	struct tc_action_net *tn = net_generic(net, xt_net_id); | 
 |  | 
 | 	return tcf_generic_walker(tn, skb, cb, type, ops); | 
 | } | 
 |  | 
 | static int tcf_xt_search(struct net *net, struct tc_action **a, u32 index) | 
 | { | 
 | 	struct tc_action_net *tn = net_generic(net, xt_net_id); | 
 |  | 
 | 	return tcf_hash_search(tn, a, index); | 
 | } | 
 |  | 
 | static struct tc_action_ops act_xt_ops = { | 
 | 	.kind		=	"xt", | 
 | 	.type		=	TCA_ACT_XT, | 
 | 	.owner		=	THIS_MODULE, | 
 | 	.act		=	tcf_ipt, | 
 | 	.dump		=	tcf_ipt_dump, | 
 | 	.cleanup	=	tcf_ipt_release, | 
 | 	.init		=	tcf_xt_init, | 
 | 	.walk		=	tcf_xt_walker, | 
 | 	.lookup		=	tcf_xt_search, | 
 | 	.size		=	sizeof(struct tcf_ipt), | 
 | }; | 
 |  | 
 | static __net_init int xt_init_net(struct net *net) | 
 | { | 
 | 	struct tc_action_net *tn = net_generic(net, xt_net_id); | 
 |  | 
 | 	return tc_action_net_init(tn, &act_xt_ops, IPT_TAB_MASK); | 
 | } | 
 |  | 
 | static void __net_exit xt_exit_net(struct net *net) | 
 | { | 
 | 	struct tc_action_net *tn = net_generic(net, xt_net_id); | 
 |  | 
 | 	tc_action_net_exit(tn); | 
 | } | 
 |  | 
 | static struct pernet_operations xt_net_ops = { | 
 | 	.init = xt_init_net, | 
 | 	.exit = xt_exit_net, | 
 | 	.id   = &xt_net_id, | 
 | 	.size = sizeof(struct tc_action_net), | 
 | }; | 
 |  | 
 | MODULE_AUTHOR("Jamal Hadi Salim(2002-13)"); | 
 | MODULE_DESCRIPTION("Iptables target actions"); | 
 | MODULE_LICENSE("GPL"); | 
 | MODULE_ALIAS("act_xt"); | 
 |  | 
 | static int __init ipt_init_module(void) | 
 | { | 
 | 	int ret1, ret2; | 
 |  | 
 | 	ret1 = tcf_register_action(&act_xt_ops, &xt_net_ops); | 
 | 	if (ret1 < 0) | 
 | 		pr_err("Failed to load xt action\n"); | 
 |  | 
 | 	ret2 = tcf_register_action(&act_ipt_ops, &ipt_net_ops); | 
 | 	if (ret2 < 0) | 
 | 		pr_err("Failed to load ipt action\n"); | 
 |  | 
 | 	if (ret1 < 0 && ret2 < 0) { | 
 | 		return ret1; | 
 | 	} else | 
 | 		return 0; | 
 | } | 
 |  | 
 | static void __exit ipt_cleanup_module(void) | 
 | { | 
 | 	tcf_unregister_action(&act_ipt_ops, &ipt_net_ops); | 
 | 	tcf_unregister_action(&act_xt_ops, &xt_net_ops); | 
 | } | 
 |  | 
 | module_init(ipt_init_module); | 
 | module_exit(ipt_cleanup_module); |