From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- net/sched/act_ipt.c | 311 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 311 insertions(+) create mode 100644 net/sched/act_ipt.c (limited to 'net/sched/act_ipt.c') diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c new file mode 100644 index 000000000..cbc8dd7dd --- /dev/null +++ b/net/sched/act_ipt.c @@ -0,0 +1,311 @@ +/* + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + + +#define IPT_TAB_MASK 15 + +static int ipt_init_target(struct xt_entry_target *t, char *table, unsigned int hook) +{ + struct xt_tgchk_param par; + struct xt_target *target; + 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; + par.table = table; + par.entryinfo = NULL; + 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, + }; + 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, 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 xt_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 xt_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]); + + if (!tcf_hash_check(index, a, bind) ) { + ret = tcf_hash_create(index, est, a, sizeof(*ipt), bind); + 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; + } + ipt = to_ipt(a); + + 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(t, tname, hook); + if (err < 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(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(struct sk_buff *skb, const struct tc_action *a, + struct tcf_result *res) +{ + int ret = 0, result = 0; + struct tcf_ipt *ipt = a->priv; + struct xt_action_param par; + + if (skb_unclone(skb, GFP_ATOMIC)) + return TC_ACT_UNSPEC; + + spin_lock(&ipt->tcf_lock); + + ipt->tcf_tm.lastuse = jiffies; + 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.in = skb->dev; + par.out = NULL; + par.hooknum = ipt->tcfi_hook; + 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_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 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; + 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); + if (nla_put(skb, TCA_IPT_TM, sizeof (tm), &tm)) + goto nla_put_failure; + 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", + .type = TCA_ACT_IPT, + .owner = THIS_MODULE, + .act = tcf_ipt, + .dump = tcf_ipt_dump, + .cleanup = tcf_ipt_release, + .init = tcf_ipt_init, +}; + +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_ipt_init, +}; + +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, IPT_TAB_MASK); + if (ret1 < 0) + printk("Failed to load xt action\n"); + ret2 = tcf_register_action(&act_ipt_ops, IPT_TAB_MASK); + if (ret2 < 0) + printk("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_xt_ops); + tcf_unregister_action(&act_ipt_ops); +} + +module_init(ipt_init_module); +module_exit(ipt_cleanup_module); -- cgit v1.2.3-54-g00ecf