| /* |
| * net/sched/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 (2002-4) |
| */ |
| |
| #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/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 struct tcf_common *tcf_ipt_ht[IPT_TAB_MASK + 1]; |
| static u32 ipt_idx_gen; |
| static DEFINE_RWLOCK(ipt_lock); |
| |
| static struct tcf_hashinfo ipt_hash_info = { |
| .htab = tcf_ipt_ht, |
| .hmask = IPT_TAB_MASK, |
| .lock = &ipt_lock, |
| }; |
| |
| static int ipt_init_target(struct ipt_entry_target *t, char *table, unsigned int hook) |
| { |
| struct xt_target *target; |
| int ret = 0; |
| |
| target = xt_request_find_target(AF_INET, t->u.user.name, |
| t->u.user.revision); |
| if (!target) |
| return -ENOENT; |
| |
| t->u.kernel.target = target; |
| |
| ret = xt_check_target(target, AF_INET, t->u.target_size - sizeof(*t), |
| table, hook, 0, 0, NULL, t->data); |
| if (ret < 0) { |
| module_put(t->u.kernel.target->me); |
| return ret; |
| } |
| return 0; |
| } |
| |
| static void ipt_destroy_target(struct ipt_entry_target *t) |
| { |
| if (t->u.kernel.target->destroy) |
| t->u.kernel.target->destroy(t->u.kernel.target, t->data); |
| module_put(t->u.kernel.target->me); |
| } |
| |
| static int tcf_ipt_release(struct tcf_ipt *ipt, int bind) |
| { |
| int ret = 0; |
| if (ipt) { |
| if (bind) |
| ipt->tcf_bindcnt--; |
| ipt->tcf_refcnt--; |
| if (ipt->tcf_bindcnt <= 0 && ipt->tcf_refcnt <= 0) { |
| ipt_destroy_target(ipt->tcfi_t); |
| kfree(ipt->tcfi_tname); |
| kfree(ipt->tcfi_t); |
| tcf_hash_destroy(&ipt->common, &ipt_hash_info); |
| ret = ACT_P_DELETED; |
| } |
| } |
| return ret; |
| } |
| |
| 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 ipt_entry_target) }, |
| }; |
| |
| static int tcf_ipt_init(struct nlattr *nla, struct nlattr *est, |
| struct tc_action *a, int ovr, int bind) |
| { |
| struct nlattr *tb[TCA_IPT_MAX + 1]; |
| struct tcf_ipt *ipt; |
| struct tcf_common *pc; |
| struct ipt_entry_target *td, *t; |
| char *tname; |
| 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); |
| if (err < 0) |
| return err; |
| |
| if (tb[TCA_IPT_HOOK] == NULL) |
| return -EINVAL; |
| if (tb[TCA_IPT_TARG] == NULL) |
| return -EINVAL; |
| |
| td = (struct ipt_entry_target *)nla_data(tb[TCA_IPT_TARG]); |
| if (nla_len(tb[TCA_IPT_TARG]) < td->u.target_size) |
| return -EINVAL; |
| |
| if (tb[TCA_IPT_INDEX] != NULL) |
| index = nla_get_u32(tb[TCA_IPT_INDEX]); |
| |
| pc = tcf_hash_check(index, a, bind, &ipt_hash_info); |
| if (!pc) { |
| pc = tcf_hash_create(index, est, a, sizeof(*ipt), bind, |
| &ipt_idx_gen, &ipt_hash_info); |
| if (unlikely(!pc)) |
| return -ENOMEM; |
| ret = ACT_P_CREATED; |
| } else { |
| if (!ovr) { |
| tcf_ipt_release(to_ipt(pc), bind); |
| return -EEXIST; |
| } |
| } |
| ipt = to_ipt(pc); |
| |
| 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; |
| |
| if ((err = ipt_init_target(t, tname, hook)) < 0) |
| goto err3; |
| |
| 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(pc, &ipt_hash_info); |
| return ret; |
| |
| err3: |
| kfree(t); |
| err2: |
| kfree(tname); |
| err1: |
| kfree(pc); |
| return err; |
| } |
| |
| static int tcf_ipt_cleanup(struct tc_action *a, int bind) |
| { |
| struct tcf_ipt *ipt = a->priv; |
| return tcf_ipt_release(ipt, bind); |
| } |
| |
| static int tcf_ipt(struct sk_buff *skb, struct tc_action *a, |
| struct tcf_result *res) |
| { |
| int ret = 0, result = 0; |
| struct tcf_ipt *ipt = a->priv; |
| |
| if (skb_cloned(skb)) { |
| if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) |
| return TC_ACT_UNSPEC; |
| } |
| |
| spin_lock(&ipt->tcf_lock); |
| |
| ipt->tcf_tm.lastuse = jiffies; |
| ipt->tcf_bstats.bytes += qdisc_pkt_len(skb); |
| ipt->tcf_bstats.packets++; |
| |
| /* yes, we have to worry about both in and out dev |
| worry later - danger - this API seems to have changed |
| from earlier kernels */ |
| ret = ipt->tcfi_t->u.kernel.target->target(skb, skb->dev, NULL, |
| ipt->tcfi_hook, |
| ipt->tcfi_t->u.kernel.target, |
| ipt->tcfi_t->data); |
| switch (ret) { |
| case NF_ACCEPT: |
| result = TC_ACT_OK; |
| break; |
| case NF_DROP: |
| result = TC_ACT_SHOT; |
| ipt->tcf_qstats.drops++; |
| break; |
| case IPT_CONTINUE: |
| result = TC_ACT_PIPE; |
| break; |
| default: |
| if (net_ratelimit()) |
| printk("Bogus netfilter code %d assume ACCEPT\n", ret); |
| result = TC_POLICE_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 = a->priv; |
| struct ipt_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); |
| |
| 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); |
| tm.install = jiffies_to_clock_t(jiffies - ipt->tcf_tm.install); |
| tm.lastuse = jiffies_to_clock_t(jiffies - ipt->tcf_tm.lastuse); |
| tm.expires = jiffies_to_clock_t(ipt->tcf_tm.expires); |
| NLA_PUT(skb, TCA_IPT_TM, sizeof (tm), &tm); |
| kfree(t); |
| return skb->len; |
| |
| nla_put_failure: |
| nlmsg_trim(skb, b); |
| kfree(t); |
| return -1; |
| } |
| |
| static struct tc_action_ops act_ipt_ops = { |
| .kind = "ipt", |
| .hinfo = &ipt_hash_info, |
| .type = TCA_ACT_IPT, |
| .capab = TCA_CAP_NONE, |
| .owner = THIS_MODULE, |
| .act = tcf_ipt, |
| .dump = tcf_ipt_dump, |
| .cleanup = tcf_ipt_cleanup, |
| .lookup = tcf_hash_search, |
| .init = tcf_ipt_init, |
| .walk = tcf_generic_walker |
| }; |
| |
| MODULE_AUTHOR("Jamal Hadi Salim(2002-4)"); |
| MODULE_DESCRIPTION("Iptables target actions"); |
| MODULE_LICENSE("GPL"); |
| |
| static int __init ipt_init_module(void) |
| { |
| return tcf_register_action(&act_ipt_ops); |
| } |
| |
| static void __exit ipt_cleanup_module(void) |
| { |
| tcf_unregister_action(&act_ipt_ops); |
| } |
| |
| module_init(ipt_init_module); |
| module_exit(ipt_cleanup_module); |