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-rw-r--r--net/sched/act_ipt.c452
1 files changed, 452 insertions, 0 deletions
diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c
new file mode 100644
index 000000000..29974de68
--- /dev/null
+++ b/net/sched/act_ipt.c
@@ -0,0 +1,452 @@
+// 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 struct tc_action_ops act_ipt_ops;
+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 = 1 << 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] = NLA_POLICY_RANGE(NLA_U32, NF_INET_PRE_ROUTING,
+ NF_INET_NUMHOOKS),
+ [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,
+ struct tcf_proto *tp, u32 flags)
+{
+ struct tc_action_net *tn = net_generic(net, id);
+ bool bind = flags & TCA_ACT_FLAGS_BIND;
+ 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, flags);
+ if (ret) {
+ tcf_idr_cleanup(tn, index);
+ return ret;
+ }
+ ret = ACT_P_CREATED;
+ } else {
+ if (bind)/* dont override defaults */
+ return 0;
+
+ if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
+ tcf_idr_release(*a, bind);
+ return -EEXIST;
+ }
+ }
+
+ err = -EINVAL;
+ hook = nla_get_u32(tb[TCA_IPT_HOOK]);
+ switch (hook) {
+ case NF_INET_PRE_ROUTING:
+ break;
+ case NF_INET_POST_ROUTING:
+ break;
+ default:
+ goto err1;
+ }
+
+ if (tb[TCA_IPT_TABLE]) {
+ /* mangle only for now */
+ if (nla_strcmp(tb[TCA_IPT_TABLE], "mangle"))
+ goto err1;
+ }
+
+ tname = kstrdup("mangle", GFP_KERNEL);
+ if (unlikely(!tname))
+ goto err1;
+
+ 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);
+ 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,
+ struct tcf_proto *tp,
+ u32 flags, struct netlink_ext_ack *extack)
+{
+ return __tcf_ipt_init(net, act_ipt_ops.net_id, nla, est,
+ a, &act_ipt_ops, tp, flags);
+}
+
+static int tcf_xt_init(struct net *net, struct nlattr *nla,
+ struct nlattr *est, struct tc_action **a,
+ struct tcf_proto *tp,
+ u32 flags, struct netlink_ext_ack *extack)
+{
+ return __tcf_ipt_init(net, act_xt_ops.net_id, nla, est,
+ a, &act_xt_ops, tp, flags);
+}
+
+static bool tcf_ipt_act_check(struct sk_buff *skb)
+{
+ const struct iphdr *iph;
+ unsigned int nhoff, len;
+
+ if (!pskb_may_pull(skb, sizeof(struct iphdr)))
+ return false;
+
+ nhoff = skb_network_offset(skb);
+ iph = ip_hdr(skb);
+ if (iph->ihl < 5 || iph->version != 4)
+ return false;
+
+ len = skb_ip_totlen(skb);
+ if (skb->len < nhoff + len || len < (iph->ihl * 4u))
+ return false;
+
+ return pskb_may_pull(skb, iph->ihl * 4u);
+}
+
+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_protocol(skb, false) != htons(ETH_P_IP))
+ return TC_ACT_UNSPEC;
+
+ if (skb_unclone(skb, GFP_ATOMIC))
+ return TC_ACT_UNSPEC;
+
+ if (!tcf_ipt_act_check(skb))
+ return TC_ACT_UNSPEC;
+
+ if (state.hook == NF_INET_POST_ROUTING) {
+ if (!skb_dst(skb))
+ return TC_ACT_UNSPEC;
+
+ state.out = skb->dev;
+ }
+
+ 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 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,
+ .size = sizeof(struct tcf_ipt),
+};
+
+static __net_init int ipt_init_net(struct net *net)
+{
+ struct tc_action_net *tn = net_generic(net, act_ipt_ops.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, act_ipt_ops.net_id);
+}
+
+static struct pernet_operations ipt_net_ops = {
+ .init = ipt_init_net,
+ .exit_batch = ipt_exit_net,
+ .id = &act_ipt_ops.net_id,
+ .size = sizeof(struct tc_action_net),
+};
+
+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,
+ .size = sizeof(struct tcf_ipt),
+};
+
+static __net_init int xt_init_net(struct net *net)
+{
+ struct tc_action_net *tn = net_generic(net, act_xt_ops.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, act_xt_ops.net_id);
+}
+
+static struct pernet_operations xt_net_ops = {
+ .init = xt_init_net,
+ .exit_batch = xt_exit_net,
+ .id = &act_xt_ops.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);