/net/sched/act_ipt.c
http://github.com/mirrors/linux · C · 448 lines · 362 code · 70 blank · 16 comment · 44 complexity · d0ffb2f4f99b58127362e87d22c3a959 MD5 · raw file
- // SPDX-License-Identifier: GPL-2.0-or-later
- /*
- * net/sched/act_ipt.c iptables target interface
- *
- *TODO: Add other tables. For now we only support the ipv4 table targets
- *
- * 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>
- 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 net *net)
- {
- struct xt_tgdtor_param par = {
- .target = t->u.kernel.target,
- .targinfo = t->data,
- .family = NFPROTO_IPV4,
- .net = net,
- };
- if (par.target->destroy != NULL)
- par.target->destroy(&par);
- module_put(par.target->me);
- }
- static void tcf_ipt_release(struct tc_action *a)
- {
- struct tcf_ipt *ipt = to_ipt(a);
- if (ipt->tcfi_t) {
- ipt_destroy_target(ipt->tcfi_t, a->idrinfo->net);
- kfree(ipt->tcfi_t);
- }
- kfree(ipt->tcfi_tname);
- }
- 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 tcf_proto *tp, u32 flags)
- {
- 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_deprecated(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]);
- err = tcf_idr_check_alloc(tn, &index, a, bind);
- if (err < 0)
- return err;
- exists = err;
- if (exists && bind)
- return 0;
- if (tb[TCA_IPT_HOOK] == NULL || tb[TCA_IPT_TARG] == NULL) {
- if (exists)
- tcf_idr_release(*a, bind);
- else
- tcf_idr_cleanup(tn, index);
- 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_idr_release(*a, bind);
- else
- tcf_idr_cleanup(tn, index);
- return -EINVAL;
- }
- if (!exists) {
- ret = tcf_idr_create(tn, index, est, a, ops, bind,
- false, 0);
- if (ret) {
- tcf_idr_cleanup(tn, index);
- return ret;
- }
- ret = ACT_P_CREATED;
- } else {
- if (bind)/* dont override defaults */
- return 0;
- if (!ovr) {
- tcf_idr_release(*a, bind);
- 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, net);
- 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_idr_insert(tn, *a);
- return ret;
- err3:
- kfree(t);
- err2:
- kfree(tname);
- err1:
- tcf_idr_release(*a, bind);
- return err;
- }
- static int tcf_ipt_init(struct net *net, struct nlattr *nla,
- struct nlattr *est, struct tc_action **a, int ovr,
- int bind, bool rtnl_held, struct tcf_proto *tp,
- u32 flags, struct netlink_ext_ack *extack)
- {
- return __tcf_ipt_init(net, ipt_net_id, nla, est, a, &act_ipt_ops, ovr,
- bind, tp, flags);
- }
- static int tcf_xt_init(struct net *net, struct nlattr *nla,
- struct nlattr *est, struct tc_action **a, int ovr,
- int bind, bool unlocked, struct tcf_proto *tp,
- u32 flags, struct netlink_ext_ack *extack)
- {
- return __tcf_ipt_init(net, xt_net_id, nla, est, a, &act_xt_ops, ovr,
- bind, tp, flags);
- }
- static int tcf_ipt_act(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
- */
- spin_lock_bh(&ipt->tcf_lock);
- t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC);
- if (unlikely(!t))
- goto nla_put_failure;
- c.bindcnt = atomic_read(&ipt->tcf_bindcnt) - bind;
- c.refcnt = refcount_read(&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;
- spin_unlock_bh(&ipt->tcf_lock);
- kfree(t);
- return skb->len;
- nla_put_failure:
- spin_unlock_bh(&ipt->tcf_lock);
- 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 netlink_ext_ack *extack)
- {
- struct tc_action_net *tn = net_generic(net, ipt_net_id);
- return tcf_generic_walker(tn, skb, cb, type, ops, extack);
- }
- 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_idr_search(tn, a, index);
- }
- static struct tc_action_ops act_ipt_ops = {
- .kind = "ipt",
- .id = TCA_ID_IPT,
- .owner = THIS_MODULE,
- .act = tcf_ipt_act,
- .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(net, tn, &act_ipt_ops);
- }
- static void __net_exit ipt_exit_net(struct list_head *net_list)
- {
- tc_action_net_exit(net_list, ipt_net_id);
- }
- static struct pernet_operations ipt_net_ops = {
- .init = ipt_init_net,
- .exit_batch = 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 netlink_ext_ack *extack)
- {
- struct tc_action_net *tn = net_generic(net, xt_net_id);
- return tcf_generic_walker(tn, skb, cb, type, ops, extack);
- }
- 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_idr_search(tn, a, index);
- }
- static struct tc_action_ops act_xt_ops = {
- .kind = "xt",
- .id = TCA_ID_XT,
- .owner = THIS_MODULE,
- .act = tcf_ipt_act,
- .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(net, tn, &act_xt_ops);
- }
- static void __net_exit xt_exit_net(struct list_head *net_list)
- {
- tc_action_net_exit(net_list, xt_net_id);
- }
- static struct pernet_operations xt_net_ops = {
- .init = xt_init_net,
- .exit_batch = 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);