980 lines
23 KiB
C
980 lines
23 KiB
C
// SPDX-License-Identifier: GPL-2.0
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#include <linux/types.h>
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#include <linux/netfilter.h>
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#include <linux/module.h>
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#include <linux/slab.h>
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#include <linux/mutex.h>
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#include <linux/vmalloc.h>
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#include <linux/stddef.h>
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#include <linux/err.h>
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#include <linux/percpu.h>
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#include <linux/notifier.h>
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#include <linux/kernel.h>
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#include <linux/netdevice.h>
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#include <net/netfilter/nf_conntrack.h>
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#include <net/netfilter/nf_conntrack_l4proto.h>
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#include <net/netfilter/nf_conntrack_core.h>
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#include <net/netfilter/nf_log.h>
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#include <linux/ip.h>
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#include <linux/icmp.h>
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#include <linux/sysctl.h>
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#include <net/route.h>
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#include <net/ip.h>
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#include <linux/netfilter_ipv4.h>
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#include <linux/netfilter_ipv6.h>
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#include <linux/netfilter_ipv6/ip6_tables.h>
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#include <net/netfilter/nf_conntrack_helper.h>
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#include <net/netfilter/nf_conntrack_zones.h>
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#include <net/netfilter/nf_conntrack_seqadj.h>
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#include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
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#include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
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#include <net/netfilter/nf_nat_helper.h>
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#include <net/netfilter/ipv4/nf_defrag_ipv4.h>
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#include <net/netfilter/ipv6/nf_defrag_ipv6.h>
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#include <linux/ipv6.h>
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#include <linux/in6.h>
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#include <net/ipv6.h>
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#include <net/inet_frag.h>
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extern unsigned int nf_conntrack_net_id;
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static struct nf_conntrack_l4proto __rcu *nf_ct_protos[MAX_NF_CT_PROTO + 1] __read_mostly;
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static DEFINE_MUTEX(nf_ct_proto_mutex);
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#ifdef CONFIG_SYSCTL
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static int
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nf_ct_register_sysctl(struct net *net,
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struct ctl_table_header **header,
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const char *path,
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struct ctl_table *table)
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{
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if (*header == NULL) {
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*header = register_net_sysctl(net, path, table);
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if (*header == NULL)
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return -ENOMEM;
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}
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return 0;
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}
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static void
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nf_ct_unregister_sysctl(struct ctl_table_header **header,
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struct ctl_table **table,
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unsigned int users)
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{
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if (users > 0)
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return;
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unregister_net_sysctl_table(*header);
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kfree(*table);
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*header = NULL;
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*table = NULL;
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}
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__printf(5, 6)
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void nf_l4proto_log_invalid(const struct sk_buff *skb,
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struct net *net,
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u16 pf, u8 protonum,
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const char *fmt, ...)
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{
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struct va_format vaf;
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va_list args;
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if (net->ct.sysctl_log_invalid != protonum ||
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net->ct.sysctl_log_invalid != IPPROTO_RAW)
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return;
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va_start(args, fmt);
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vaf.fmt = fmt;
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vaf.va = &args;
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nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
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"nf_ct_proto_%d: %pV ", protonum, &vaf);
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va_end(args);
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}
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EXPORT_SYMBOL_GPL(nf_l4proto_log_invalid);
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__printf(3, 4)
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void nf_ct_l4proto_log_invalid(const struct sk_buff *skb,
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const struct nf_conn *ct,
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const char *fmt, ...)
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{
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struct va_format vaf;
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struct net *net;
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va_list args;
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net = nf_ct_net(ct);
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if (likely(net->ct.sysctl_log_invalid == 0))
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return;
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va_start(args, fmt);
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vaf.fmt = fmt;
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vaf.va = &args;
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nf_l4proto_log_invalid(skb, net, nf_ct_l3num(ct),
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nf_ct_protonum(ct), "%pV", &vaf);
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va_end(args);
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}
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EXPORT_SYMBOL_GPL(nf_ct_l4proto_log_invalid);
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#endif
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const struct nf_conntrack_l4proto *__nf_ct_l4proto_find(u8 l4proto)
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{
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if (unlikely(l4proto >= ARRAY_SIZE(nf_ct_protos)))
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return &nf_conntrack_l4proto_generic;
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return rcu_dereference(nf_ct_protos[l4proto]);
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}
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EXPORT_SYMBOL_GPL(__nf_ct_l4proto_find);
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const struct nf_conntrack_l4proto *nf_ct_l4proto_find_get(u8 l4num)
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{
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const struct nf_conntrack_l4proto *p;
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rcu_read_lock();
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p = __nf_ct_l4proto_find(l4num);
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if (!try_module_get(p->me))
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p = &nf_conntrack_l4proto_generic;
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rcu_read_unlock();
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return p;
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}
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EXPORT_SYMBOL_GPL(nf_ct_l4proto_find_get);
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void nf_ct_l4proto_put(const struct nf_conntrack_l4proto *p)
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{
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module_put(p->me);
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}
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EXPORT_SYMBOL_GPL(nf_ct_l4proto_put);
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static int kill_l4proto(struct nf_conn *i, void *data)
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{
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const struct nf_conntrack_l4proto *l4proto;
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l4proto = data;
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return nf_ct_protonum(i) == l4proto->l4proto;
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}
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static struct nf_proto_net *nf_ct_l4proto_net(struct net *net,
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const struct nf_conntrack_l4proto *l4proto)
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{
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if (l4proto->get_net_proto) {
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/* statically built-in protocols use static per-net */
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return l4proto->get_net_proto(net);
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} else if (l4proto->net_id) {
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/* ... and loadable protocols use dynamic per-net */
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return net_generic(net, *l4proto->net_id);
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}
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return NULL;
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}
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static
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int nf_ct_l4proto_register_sysctl(struct net *net,
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struct nf_proto_net *pn)
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{
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int err = 0;
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#ifdef CONFIG_SYSCTL
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if (pn->ctl_table != NULL) {
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err = nf_ct_register_sysctl(net,
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&pn->ctl_table_header,
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"net/netfilter",
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pn->ctl_table);
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if (err < 0) {
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if (!pn->users) {
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kfree(pn->ctl_table);
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pn->ctl_table = NULL;
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}
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}
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}
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#endif /* CONFIG_SYSCTL */
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return err;
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}
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static
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void nf_ct_l4proto_unregister_sysctl(struct nf_proto_net *pn)
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{
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#ifdef CONFIG_SYSCTL
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if (pn->ctl_table_header != NULL)
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nf_ct_unregister_sysctl(&pn->ctl_table_header,
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&pn->ctl_table,
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pn->users);
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#endif /* CONFIG_SYSCTL */
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}
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/* FIXME: Allow NULL functions and sub in pointers to generic for
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them. --RR */
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int nf_ct_l4proto_register_one(const struct nf_conntrack_l4proto *l4proto)
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{
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int ret = 0;
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if ((l4proto->to_nlattr && l4proto->nlattr_size == 0) ||
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(l4proto->tuple_to_nlattr && !l4proto->nlattr_tuple_size))
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return -EINVAL;
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mutex_lock(&nf_ct_proto_mutex);
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if (rcu_dereference_protected(
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nf_ct_protos[l4proto->l4proto],
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lockdep_is_held(&nf_ct_proto_mutex)
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) != &nf_conntrack_l4proto_generic) {
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ret = -EBUSY;
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goto out_unlock;
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}
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rcu_assign_pointer(nf_ct_protos[l4proto->l4proto], l4proto);
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out_unlock:
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mutex_unlock(&nf_ct_proto_mutex);
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return ret;
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}
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EXPORT_SYMBOL_GPL(nf_ct_l4proto_register_one);
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int nf_ct_l4proto_pernet_register_one(struct net *net,
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const struct nf_conntrack_l4proto *l4proto)
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{
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int ret = 0;
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struct nf_proto_net *pn = NULL;
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if (l4proto->init_net) {
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ret = l4proto->init_net(net);
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if (ret < 0)
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goto out;
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}
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pn = nf_ct_l4proto_net(net, l4proto);
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if (pn == NULL)
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goto out;
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ret = nf_ct_l4proto_register_sysctl(net, pn);
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if (ret < 0)
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goto out;
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pn->users++;
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out:
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return ret;
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}
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EXPORT_SYMBOL_GPL(nf_ct_l4proto_pernet_register_one);
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static void __nf_ct_l4proto_unregister_one(const struct nf_conntrack_l4proto *l4proto)
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{
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BUG_ON(l4proto->l4proto >= ARRAY_SIZE(nf_ct_protos));
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BUG_ON(rcu_dereference_protected(
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nf_ct_protos[l4proto->l4proto],
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lockdep_is_held(&nf_ct_proto_mutex)
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) != l4proto);
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rcu_assign_pointer(nf_ct_protos[l4proto->l4proto],
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&nf_conntrack_l4proto_generic);
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}
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void nf_ct_l4proto_unregister_one(const struct nf_conntrack_l4proto *l4proto)
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{
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mutex_lock(&nf_ct_proto_mutex);
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__nf_ct_l4proto_unregister_one(l4proto);
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mutex_unlock(&nf_ct_proto_mutex);
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synchronize_net();
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/* Remove all contrack entries for this protocol */
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nf_ct_iterate_destroy(kill_l4proto, (void *)l4proto);
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}
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EXPORT_SYMBOL_GPL(nf_ct_l4proto_unregister_one);
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void nf_ct_l4proto_pernet_unregister_one(struct net *net,
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const struct nf_conntrack_l4proto *l4proto)
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{
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struct nf_proto_net *pn = nf_ct_l4proto_net(net, l4proto);
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if (pn == NULL)
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return;
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pn->users--;
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nf_ct_l4proto_unregister_sysctl(pn);
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}
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EXPORT_SYMBOL_GPL(nf_ct_l4proto_pernet_unregister_one);
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static void
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nf_ct_l4proto_unregister(const struct nf_conntrack_l4proto * const l4proto[],
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unsigned int num_proto)
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{
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int i;
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mutex_lock(&nf_ct_proto_mutex);
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for (i = 0; i < num_proto; i++)
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__nf_ct_l4proto_unregister_one(l4proto[i]);
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mutex_unlock(&nf_ct_proto_mutex);
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synchronize_net();
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for (i = 0; i < num_proto; i++)
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nf_ct_iterate_destroy(kill_l4proto, (void *)l4proto[i]);
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}
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static int
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nf_ct_l4proto_register(const struct nf_conntrack_l4proto * const l4proto[],
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unsigned int num_proto)
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{
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int ret = -EINVAL;
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unsigned int i;
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for (i = 0; i < num_proto; i++) {
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ret = nf_ct_l4proto_register_one(l4proto[i]);
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if (ret < 0)
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break;
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}
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if (i != num_proto) {
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pr_err("nf_conntrack: can't register l4 %d proto.\n",
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l4proto[i]->l4proto);
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nf_ct_l4proto_unregister(l4proto, i);
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}
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return ret;
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}
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int nf_ct_l4proto_pernet_register(struct net *net,
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const struct nf_conntrack_l4proto *const l4proto[],
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unsigned int num_proto)
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{
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int ret = -EINVAL;
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unsigned int i;
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for (i = 0; i < num_proto; i++) {
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ret = nf_ct_l4proto_pernet_register_one(net, l4proto[i]);
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if (ret < 0)
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break;
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}
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if (i != num_proto) {
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pr_err("nf_conntrack %d: pernet registration failed\n",
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l4proto[i]->l4proto);
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nf_ct_l4proto_pernet_unregister(net, l4proto, i);
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}
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return ret;
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}
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EXPORT_SYMBOL_GPL(nf_ct_l4proto_pernet_register);
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void nf_ct_l4proto_pernet_unregister(struct net *net,
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const struct nf_conntrack_l4proto *const l4proto[],
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unsigned int num_proto)
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{
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while (num_proto-- != 0)
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nf_ct_l4proto_pernet_unregister_one(net, l4proto[num_proto]);
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}
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EXPORT_SYMBOL_GPL(nf_ct_l4proto_pernet_unregister);
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static unsigned int ipv4_helper(void *priv,
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struct sk_buff *skb,
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const struct nf_hook_state *state)
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{
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struct nf_conn *ct;
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enum ip_conntrack_info ctinfo;
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const struct nf_conn_help *help;
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const struct nf_conntrack_helper *helper;
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/* This is where we call the helper: as the packet goes out. */
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ct = nf_ct_get(skb, &ctinfo);
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if (!ct || ctinfo == IP_CT_RELATED_REPLY)
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return NF_ACCEPT;
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help = nfct_help(ct);
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if (!help)
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return NF_ACCEPT;
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/* rcu_read_lock()ed by nf_hook_thresh */
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helper = rcu_dereference(help->helper);
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if (!helper)
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return NF_ACCEPT;
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return helper->help(skb, skb_network_offset(skb) + ip_hdrlen(skb),
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ct, ctinfo);
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}
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static unsigned int ipv4_confirm(void *priv,
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struct sk_buff *skb,
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const struct nf_hook_state *state)
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{
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struct nf_conn *ct;
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enum ip_conntrack_info ctinfo;
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ct = nf_ct_get(skb, &ctinfo);
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if (!ct || ctinfo == IP_CT_RELATED_REPLY)
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goto out;
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/* adjust seqs for loopback traffic only in outgoing direction */
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if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
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!nf_is_loopback_packet(skb)) {
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if (!nf_ct_seq_adjust(skb, ct, ctinfo, ip_hdrlen(skb))) {
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NF_CT_STAT_INC_ATOMIC(nf_ct_net(ct), drop);
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return NF_DROP;
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}
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}
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out:
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/* We've seen it coming out the other side: confirm it */
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return nf_conntrack_confirm(skb);
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}
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static unsigned int ipv4_conntrack_in(void *priv,
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struct sk_buff *skb,
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const struct nf_hook_state *state)
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{
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return nf_conntrack_in(skb, state);
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}
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static unsigned int ipv4_conntrack_local(void *priv,
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struct sk_buff *skb,
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const struct nf_hook_state *state)
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{
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if (ip_is_fragment(ip_hdr(skb))) { /* IP_NODEFRAG setsockopt set */
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enum ip_conntrack_info ctinfo;
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struct nf_conn *tmpl;
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tmpl = nf_ct_get(skb, &ctinfo);
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if (tmpl && nf_ct_is_template(tmpl)) {
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/* when skipping ct, clear templates to avoid fooling
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* later targets/matches
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*/
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skb->_nfct = 0;
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nf_ct_put(tmpl);
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}
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return NF_ACCEPT;
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}
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return nf_conntrack_in(skb, state);
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}
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/* Connection tracking may drop packets, but never alters them, so
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* make it the first hook.
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*/
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static const struct nf_hook_ops ipv4_conntrack_ops[] = {
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{
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.hook = ipv4_conntrack_in,
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.pf = NFPROTO_IPV4,
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.hooknum = NF_INET_PRE_ROUTING,
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.priority = NF_IP_PRI_CONNTRACK,
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},
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{
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.hook = ipv4_conntrack_local,
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.pf = NFPROTO_IPV4,
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.hooknum = NF_INET_LOCAL_OUT,
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.priority = NF_IP_PRI_CONNTRACK,
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},
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{
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.hook = ipv4_helper,
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.pf = NFPROTO_IPV4,
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.hooknum = NF_INET_POST_ROUTING,
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.priority = NF_IP_PRI_CONNTRACK_HELPER,
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},
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{
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.hook = ipv4_confirm,
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.pf = NFPROTO_IPV4,
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.hooknum = NF_INET_POST_ROUTING,
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.priority = NF_IP_PRI_CONNTRACK_CONFIRM,
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},
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{
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.hook = ipv4_helper,
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.pf = NFPROTO_IPV4,
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.hooknum = NF_INET_LOCAL_IN,
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.priority = NF_IP_PRI_CONNTRACK_HELPER,
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},
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{
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.hook = ipv4_confirm,
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.pf = NFPROTO_IPV4,
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.hooknum = NF_INET_LOCAL_IN,
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.priority = NF_IP_PRI_CONNTRACK_CONFIRM,
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},
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};
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/* Fast function for those who don't want to parse /proc (and I don't
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* blame them).
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* Reversing the socket's dst/src point of view gives us the reply
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* mapping.
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*/
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static int
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getorigdst(struct sock *sk, int optval, void __user *user, int *len)
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{
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const struct inet_sock *inet = inet_sk(sk);
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const struct nf_conntrack_tuple_hash *h;
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struct nf_conntrack_tuple tuple;
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memset(&tuple, 0, sizeof(tuple));
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|
|
|
lock_sock(sk);
|
|
tuple.src.u3.ip = inet->inet_rcv_saddr;
|
|
tuple.src.u.tcp.port = inet->inet_sport;
|
|
tuple.dst.u3.ip = inet->inet_daddr;
|
|
tuple.dst.u.tcp.port = inet->inet_dport;
|
|
tuple.src.l3num = PF_INET;
|
|
tuple.dst.protonum = sk->sk_protocol;
|
|
release_sock(sk);
|
|
|
|
/* We only do TCP and SCTP at the moment: is there a better way? */
|
|
if (tuple.dst.protonum != IPPROTO_TCP &&
|
|
tuple.dst.protonum != IPPROTO_SCTP) {
|
|
pr_debug("SO_ORIGINAL_DST: Not a TCP/SCTP socket\n");
|
|
return -ENOPROTOOPT;
|
|
}
|
|
|
|
if ((unsigned int)*len < sizeof(struct sockaddr_in)) {
|
|
pr_debug("SO_ORIGINAL_DST: len %d not %zu\n",
|
|
*len, sizeof(struct sockaddr_in));
|
|
return -EINVAL;
|
|
}
|
|
|
|
h = nf_conntrack_find_get(sock_net(sk), &nf_ct_zone_dflt, &tuple);
|
|
if (h) {
|
|
struct sockaddr_in sin;
|
|
struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h);
|
|
|
|
sin.sin_family = AF_INET;
|
|
sin.sin_port = ct->tuplehash[IP_CT_DIR_ORIGINAL]
|
|
.tuple.dst.u.tcp.port;
|
|
sin.sin_addr.s_addr = ct->tuplehash[IP_CT_DIR_ORIGINAL]
|
|
.tuple.dst.u3.ip;
|
|
memset(sin.sin_zero, 0, sizeof(sin.sin_zero));
|
|
|
|
pr_debug("SO_ORIGINAL_DST: %pI4 %u\n",
|
|
&sin.sin_addr.s_addr, ntohs(sin.sin_port));
|
|
nf_ct_put(ct);
|
|
if (copy_to_user(user, &sin, sizeof(sin)) != 0)
|
|
return -EFAULT;
|
|
else
|
|
return 0;
|
|
}
|
|
pr_debug("SO_ORIGINAL_DST: Can't find %pI4/%u-%pI4/%u.\n",
|
|
&tuple.src.u3.ip, ntohs(tuple.src.u.tcp.port),
|
|
&tuple.dst.u3.ip, ntohs(tuple.dst.u.tcp.port));
|
|
return -ENOENT;
|
|
}
|
|
|
|
static struct nf_sockopt_ops so_getorigdst = {
|
|
.pf = PF_INET,
|
|
.get_optmin = SO_ORIGINAL_DST,
|
|
.get_optmax = SO_ORIGINAL_DST + 1,
|
|
.get = getorigdst,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
static int
|
|
ipv6_getorigdst(struct sock *sk, int optval, void __user *user, int *len)
|
|
{
|
|
struct nf_conntrack_tuple tuple = { .src.l3num = NFPROTO_IPV6 };
|
|
const struct ipv6_pinfo *inet6 = inet6_sk(sk);
|
|
const struct inet_sock *inet = inet_sk(sk);
|
|
const struct nf_conntrack_tuple_hash *h;
|
|
struct sockaddr_in6 sin6;
|
|
struct nf_conn *ct;
|
|
__be32 flow_label;
|
|
int bound_dev_if;
|
|
|
|
lock_sock(sk);
|
|
tuple.src.u3.in6 = sk->sk_v6_rcv_saddr;
|
|
tuple.src.u.tcp.port = inet->inet_sport;
|
|
tuple.dst.u3.in6 = sk->sk_v6_daddr;
|
|
tuple.dst.u.tcp.port = inet->inet_dport;
|
|
tuple.dst.protonum = sk->sk_protocol;
|
|
bound_dev_if = sk->sk_bound_dev_if;
|
|
flow_label = inet6->flow_label;
|
|
release_sock(sk);
|
|
|
|
if (tuple.dst.protonum != IPPROTO_TCP &&
|
|
tuple.dst.protonum != IPPROTO_SCTP)
|
|
return -ENOPROTOOPT;
|
|
|
|
if (*len < 0 || (unsigned int)*len < sizeof(sin6))
|
|
return -EINVAL;
|
|
|
|
h = nf_conntrack_find_get(sock_net(sk), &nf_ct_zone_dflt, &tuple);
|
|
if (!h) {
|
|
pr_debug("IP6T_SO_ORIGINAL_DST: Can't find %pI6c/%u-%pI6c/%u.\n",
|
|
&tuple.src.u3.ip6, ntohs(tuple.src.u.tcp.port),
|
|
&tuple.dst.u3.ip6, ntohs(tuple.dst.u.tcp.port));
|
|
return -ENOENT;
|
|
}
|
|
|
|
ct = nf_ct_tuplehash_to_ctrack(h);
|
|
|
|
sin6.sin6_family = AF_INET6;
|
|
sin6.sin6_port = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u.tcp.port;
|
|
sin6.sin6_flowinfo = flow_label & IPV6_FLOWINFO_MASK;
|
|
memcpy(&sin6.sin6_addr,
|
|
&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u3.in6,
|
|
sizeof(sin6.sin6_addr));
|
|
|
|
nf_ct_put(ct);
|
|
sin6.sin6_scope_id = ipv6_iface_scope_id(&sin6.sin6_addr, bound_dev_if);
|
|
return copy_to_user(user, &sin6, sizeof(sin6)) ? -EFAULT : 0;
|
|
}
|
|
|
|
static struct nf_sockopt_ops so_getorigdst6 = {
|
|
.pf = NFPROTO_IPV6,
|
|
.get_optmin = IP6T_SO_ORIGINAL_DST,
|
|
.get_optmax = IP6T_SO_ORIGINAL_DST + 1,
|
|
.get = ipv6_getorigdst,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
static unsigned int ipv6_confirm(void *priv,
|
|
struct sk_buff *skb,
|
|
const struct nf_hook_state *state)
|
|
{
|
|
struct nf_conn *ct;
|
|
enum ip_conntrack_info ctinfo;
|
|
unsigned char pnum = ipv6_hdr(skb)->nexthdr;
|
|
int protoff;
|
|
__be16 frag_off;
|
|
|
|
ct = nf_ct_get(skb, &ctinfo);
|
|
if (!ct || ctinfo == IP_CT_RELATED_REPLY)
|
|
goto out;
|
|
|
|
protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &pnum,
|
|
&frag_off);
|
|
if (protoff < 0 || (frag_off & htons(~0x7)) != 0) {
|
|
pr_debug("proto header not found\n");
|
|
goto out;
|
|
}
|
|
|
|
/* adjust seqs for loopback traffic only in outgoing direction */
|
|
if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
|
|
!nf_is_loopback_packet(skb)) {
|
|
if (!nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) {
|
|
NF_CT_STAT_INC_ATOMIC(nf_ct_net(ct), drop);
|
|
return NF_DROP;
|
|
}
|
|
}
|
|
out:
|
|
/* We've seen it coming out the other side: confirm it */
|
|
return nf_conntrack_confirm(skb);
|
|
}
|
|
|
|
static unsigned int ipv6_conntrack_in(void *priv,
|
|
struct sk_buff *skb,
|
|
const struct nf_hook_state *state)
|
|
{
|
|
return nf_conntrack_in(skb, state);
|
|
}
|
|
|
|
static unsigned int ipv6_conntrack_local(void *priv,
|
|
struct sk_buff *skb,
|
|
const struct nf_hook_state *state)
|
|
{
|
|
return nf_conntrack_in(skb, state);
|
|
}
|
|
|
|
static unsigned int ipv6_helper(void *priv,
|
|
struct sk_buff *skb,
|
|
const struct nf_hook_state *state)
|
|
{
|
|
struct nf_conn *ct;
|
|
const struct nf_conn_help *help;
|
|
const struct nf_conntrack_helper *helper;
|
|
enum ip_conntrack_info ctinfo;
|
|
__be16 frag_off;
|
|
int protoff;
|
|
u8 nexthdr;
|
|
|
|
/* This is where we call the helper: as the packet goes out. */
|
|
ct = nf_ct_get(skb, &ctinfo);
|
|
if (!ct || ctinfo == IP_CT_RELATED_REPLY)
|
|
return NF_ACCEPT;
|
|
|
|
help = nfct_help(ct);
|
|
if (!help)
|
|
return NF_ACCEPT;
|
|
/* rcu_read_lock()ed by nf_hook_thresh */
|
|
helper = rcu_dereference(help->helper);
|
|
if (!helper)
|
|
return NF_ACCEPT;
|
|
|
|
nexthdr = ipv6_hdr(skb)->nexthdr;
|
|
protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr,
|
|
&frag_off);
|
|
if (protoff < 0 || (frag_off & htons(~0x7)) != 0) {
|
|
pr_debug("proto header not found\n");
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
return helper->help(skb, protoff, ct, ctinfo);
|
|
}
|
|
|
|
static const struct nf_hook_ops ipv6_conntrack_ops[] = {
|
|
{
|
|
.hook = ipv6_conntrack_in,
|
|
.pf = NFPROTO_IPV6,
|
|
.hooknum = NF_INET_PRE_ROUTING,
|
|
.priority = NF_IP6_PRI_CONNTRACK,
|
|
},
|
|
{
|
|
.hook = ipv6_conntrack_local,
|
|
.pf = NFPROTO_IPV6,
|
|
.hooknum = NF_INET_LOCAL_OUT,
|
|
.priority = NF_IP6_PRI_CONNTRACK,
|
|
},
|
|
{
|
|
.hook = ipv6_helper,
|
|
.pf = NFPROTO_IPV6,
|
|
.hooknum = NF_INET_POST_ROUTING,
|
|
.priority = NF_IP6_PRI_CONNTRACK_HELPER,
|
|
},
|
|
{
|
|
.hook = ipv6_confirm,
|
|
.pf = NFPROTO_IPV6,
|
|
.hooknum = NF_INET_POST_ROUTING,
|
|
.priority = NF_IP6_PRI_LAST,
|
|
},
|
|
{
|
|
.hook = ipv6_helper,
|
|
.pf = NFPROTO_IPV6,
|
|
.hooknum = NF_INET_LOCAL_IN,
|
|
.priority = NF_IP6_PRI_CONNTRACK_HELPER,
|
|
},
|
|
{
|
|
.hook = ipv6_confirm,
|
|
.pf = NFPROTO_IPV6,
|
|
.hooknum = NF_INET_LOCAL_IN,
|
|
.priority = NF_IP6_PRI_LAST - 1,
|
|
},
|
|
};
|
|
#endif
|
|
|
|
static int nf_ct_tcp_fixup(struct nf_conn *ct, void *_nfproto)
|
|
{
|
|
u8 nfproto = (unsigned long)_nfproto;
|
|
|
|
if (nf_ct_l3num(ct) != nfproto)
|
|
return 0;
|
|
|
|
if (nf_ct_protonum(ct) == IPPROTO_TCP &&
|
|
ct->proto.tcp.state == TCP_CONNTRACK_ESTABLISHED) {
|
|
ct->proto.tcp.seen[0].td_maxwin = 0;
|
|
ct->proto.tcp.seen[1].td_maxwin = 0;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int nf_ct_netns_do_get(struct net *net, u8 nfproto)
|
|
{
|
|
struct nf_conntrack_net *cnet = net_generic(net, nf_conntrack_net_id);
|
|
bool fixup_needed = false;
|
|
int err = 0;
|
|
|
|
mutex_lock(&nf_ct_proto_mutex);
|
|
|
|
switch (nfproto) {
|
|
case NFPROTO_IPV4:
|
|
cnet->users4++;
|
|
if (cnet->users4 > 1)
|
|
goto out_unlock;
|
|
err = nf_defrag_ipv4_enable(net);
|
|
if (err) {
|
|
cnet->users4 = 0;
|
|
goto out_unlock;
|
|
}
|
|
|
|
err = nf_register_net_hooks(net, ipv4_conntrack_ops,
|
|
ARRAY_SIZE(ipv4_conntrack_ops));
|
|
if (err)
|
|
cnet->users4 = 0;
|
|
else
|
|
fixup_needed = true;
|
|
break;
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
case NFPROTO_IPV6:
|
|
cnet->users6++;
|
|
if (cnet->users6 > 1)
|
|
goto out_unlock;
|
|
err = nf_defrag_ipv6_enable(net);
|
|
if (err < 0) {
|
|
cnet->users6 = 0;
|
|
goto out_unlock;
|
|
}
|
|
|
|
err = nf_register_net_hooks(net, ipv6_conntrack_ops,
|
|
ARRAY_SIZE(ipv6_conntrack_ops));
|
|
if (err)
|
|
cnet->users6 = 0;
|
|
else
|
|
fixup_needed = true;
|
|
break;
|
|
#endif
|
|
default:
|
|
err = -EPROTO;
|
|
break;
|
|
}
|
|
out_unlock:
|
|
mutex_unlock(&nf_ct_proto_mutex);
|
|
|
|
if (fixup_needed)
|
|
nf_ct_iterate_cleanup_net(net, nf_ct_tcp_fixup,
|
|
(void *)(unsigned long)nfproto, 0, 0);
|
|
|
|
return err;
|
|
}
|
|
|
|
static void nf_ct_netns_do_put(struct net *net, u8 nfproto)
|
|
{
|
|
struct nf_conntrack_net *cnet = net_generic(net, nf_conntrack_net_id);
|
|
|
|
mutex_lock(&nf_ct_proto_mutex);
|
|
switch (nfproto) {
|
|
case NFPROTO_IPV4:
|
|
if (cnet->users4 && (--cnet->users4 == 0))
|
|
nf_unregister_net_hooks(net, ipv4_conntrack_ops,
|
|
ARRAY_SIZE(ipv4_conntrack_ops));
|
|
break;
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
case NFPROTO_IPV6:
|
|
if (cnet->users6 && (--cnet->users6 == 0))
|
|
nf_unregister_net_hooks(net, ipv6_conntrack_ops,
|
|
ARRAY_SIZE(ipv6_conntrack_ops));
|
|
break;
|
|
#endif
|
|
}
|
|
|
|
mutex_unlock(&nf_ct_proto_mutex);
|
|
}
|
|
|
|
int nf_ct_netns_get(struct net *net, u8 nfproto)
|
|
{
|
|
int err;
|
|
|
|
if (nfproto == NFPROTO_INET) {
|
|
err = nf_ct_netns_do_get(net, NFPROTO_IPV4);
|
|
if (err < 0)
|
|
goto err1;
|
|
err = nf_ct_netns_do_get(net, NFPROTO_IPV6);
|
|
if (err < 0)
|
|
goto err2;
|
|
} else {
|
|
err = nf_ct_netns_do_get(net, nfproto);
|
|
if (err < 0)
|
|
goto err1;
|
|
}
|
|
return 0;
|
|
|
|
err2:
|
|
nf_ct_netns_put(net, NFPROTO_IPV4);
|
|
err1:
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_netns_get);
|
|
|
|
void nf_ct_netns_put(struct net *net, uint8_t nfproto)
|
|
{
|
|
if (nfproto == NFPROTO_INET) {
|
|
nf_ct_netns_do_put(net, NFPROTO_IPV4);
|
|
nf_ct_netns_do_put(net, NFPROTO_IPV6);
|
|
} else {
|
|
nf_ct_netns_do_put(net, nfproto);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(nf_ct_netns_put);
|
|
|
|
static const struct nf_conntrack_l4proto * const builtin_l4proto[] = {
|
|
&nf_conntrack_l4proto_tcp,
|
|
&nf_conntrack_l4proto_udp,
|
|
&nf_conntrack_l4proto_icmp,
|
|
#ifdef CONFIG_NF_CT_PROTO_DCCP
|
|
&nf_conntrack_l4proto_dccp,
|
|
#endif
|
|
#ifdef CONFIG_NF_CT_PROTO_SCTP
|
|
&nf_conntrack_l4proto_sctp,
|
|
#endif
|
|
#ifdef CONFIG_NF_CT_PROTO_UDPLITE
|
|
&nf_conntrack_l4proto_udplite,
|
|
#endif
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
&nf_conntrack_l4proto_icmpv6,
|
|
#endif /* CONFIG_IPV6 */
|
|
};
|
|
|
|
int nf_conntrack_proto_init(void)
|
|
{
|
|
int ret = 0, i;
|
|
|
|
ret = nf_register_sockopt(&so_getorigdst);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
ret = nf_register_sockopt(&so_getorigdst6);
|
|
if (ret < 0)
|
|
goto cleanup_sockopt;
|
|
#endif
|
|
|
|
for (i = 0; i < ARRAY_SIZE(nf_ct_protos); i++)
|
|
RCU_INIT_POINTER(nf_ct_protos[i],
|
|
&nf_conntrack_l4proto_generic);
|
|
|
|
ret = nf_ct_l4proto_register(builtin_l4proto,
|
|
ARRAY_SIZE(builtin_l4proto));
|
|
if (ret < 0)
|
|
goto cleanup_sockopt2;
|
|
|
|
return ret;
|
|
cleanup_sockopt2:
|
|
nf_unregister_sockopt(&so_getorigdst);
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
cleanup_sockopt:
|
|
nf_unregister_sockopt(&so_getorigdst6);
|
|
#endif
|
|
return ret;
|
|
}
|
|
|
|
void nf_conntrack_proto_fini(void)
|
|
{
|
|
nf_unregister_sockopt(&so_getorigdst);
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
nf_unregister_sockopt(&so_getorigdst6);
|
|
#endif
|
|
}
|
|
|
|
int nf_conntrack_proto_pernet_init(struct net *net)
|
|
{
|
|
int err;
|
|
struct nf_proto_net *pn = nf_ct_l4proto_net(net,
|
|
&nf_conntrack_l4proto_generic);
|
|
|
|
err = nf_conntrack_l4proto_generic.init_net(net);
|
|
if (err < 0)
|
|
return err;
|
|
err = nf_ct_l4proto_register_sysctl(net,
|
|
pn);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
err = nf_ct_l4proto_pernet_register(net, builtin_l4proto,
|
|
ARRAY_SIZE(builtin_l4proto));
|
|
if (err < 0) {
|
|
nf_ct_l4proto_unregister_sysctl(pn);
|
|
return err;
|
|
}
|
|
|
|
pn->users++;
|
|
return 0;
|
|
}
|
|
|
|
void nf_conntrack_proto_pernet_fini(struct net *net)
|
|
{
|
|
struct nf_proto_net *pn = nf_ct_l4proto_net(net,
|
|
&nf_conntrack_l4proto_generic);
|
|
|
|
nf_ct_l4proto_pernet_unregister(net, builtin_l4proto,
|
|
ARRAY_SIZE(builtin_l4proto));
|
|
pn->users--;
|
|
nf_ct_l4proto_unregister_sysctl(pn);
|
|
}
|
|
|
|
|
|
module_param_call(hashsize, nf_conntrack_set_hashsize, param_get_uint,
|
|
&nf_conntrack_htable_size, 0600);
|
|
|
|
MODULE_ALIAS("ip_conntrack");
|
|
MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET));
|
|
MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6));
|
|
MODULE_LICENSE("GPL");
|