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-rw-r--r--net/sched/act_ipt.c317
1 files changed, 317 insertions, 0 deletions
diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c
new file mode 100644
index 00000000..60f8f616
--- /dev/null
+++ b/net/sched/act_ipt.c
@@ -0,0 +1,317 @@
+/*
+ * 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 <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 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 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 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 xt_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 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]);
+
+ 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 (IS_ERR(pc))
+ return PTR_ERR(pc);
+ 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;
+
+ 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(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, 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_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;
+ 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:
+ if (net_ratelimit())
+ pr_notice("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);
+
+ 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);