remarkable-linux/net/netfilter/nf_conntrack_netlink.c
Pablo Neira Ayuso 80e60e67bc netfilter: ctnetlink: get and zero operations must be atomic
The get and zero operations have to be done in an atomic context,
otherwise counters added between them will be lost.

This problem was spotted by Changli Gao while discussing the
nfacct infrastructure.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2011-12-24 14:35:59 +01:00

2272 lines
54 KiB
C

/* Connection tracking via netlink socket. Allows for user space
* protocol helpers and general trouble making from userspace.
*
* (C) 2001 by Jay Schulist <jschlst@samba.org>
* (C) 2002-2006 by Harald Welte <laforge@gnumonks.org>
* (C) 2003 by Patrick Mchardy <kaber@trash.net>
* (C) 2005-2011 by Pablo Neira Ayuso <pablo@netfilter.org>
*
* Initial connection tracking via netlink development funded and
* generally made possible by Network Robots, Inc. (www.networkrobots.com)
*
* Further development of this code funded by Astaro AG (http://www.astaro.com)
*
* This software may be used and distributed according to the terms
* of the GNU General Public License, incorporated herein by reference.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/rculist.h>
#include <linux/rculist_nulls.h>
#include <linux/types.h>
#include <linux/timer.h>
#include <linux/security.h>
#include <linux/skbuff.h>
#include <linux/errno.h>
#include <linux/netlink.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/netfilter.h>
#include <net/netlink.h>
#include <net/sock.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_conntrack_core.h>
#include <net/netfilter/nf_conntrack_expect.h>
#include <net/netfilter/nf_conntrack_helper.h>
#include <net/netfilter/nf_conntrack_l3proto.h>
#include <net/netfilter/nf_conntrack_l4proto.h>
#include <net/netfilter/nf_conntrack_tuple.h>
#include <net/netfilter/nf_conntrack_acct.h>
#include <net/netfilter/nf_conntrack_zones.h>
#include <net/netfilter/nf_conntrack_timestamp.h>
#ifdef CONFIG_NF_NAT_NEEDED
#include <net/netfilter/nf_nat_core.h>
#include <net/netfilter/nf_nat_protocol.h>
#endif
#include <linux/netfilter/nfnetlink.h>
#include <linux/netfilter/nfnetlink_conntrack.h>
MODULE_LICENSE("GPL");
static char __initdata version[] = "0.93";
static inline int
ctnetlink_dump_tuples_proto(struct sk_buff *skb,
const struct nf_conntrack_tuple *tuple,
struct nf_conntrack_l4proto *l4proto)
{
int ret = 0;
struct nlattr *nest_parms;
nest_parms = nla_nest_start(skb, CTA_TUPLE_PROTO | NLA_F_NESTED);
if (!nest_parms)
goto nla_put_failure;
NLA_PUT_U8(skb, CTA_PROTO_NUM, tuple->dst.protonum);
if (likely(l4proto->tuple_to_nlattr))
ret = l4proto->tuple_to_nlattr(skb, tuple);
nla_nest_end(skb, nest_parms);
return ret;
nla_put_failure:
return -1;
}
static inline int
ctnetlink_dump_tuples_ip(struct sk_buff *skb,
const struct nf_conntrack_tuple *tuple,
struct nf_conntrack_l3proto *l3proto)
{
int ret = 0;
struct nlattr *nest_parms;
nest_parms = nla_nest_start(skb, CTA_TUPLE_IP | NLA_F_NESTED);
if (!nest_parms)
goto nla_put_failure;
if (likely(l3proto->tuple_to_nlattr))
ret = l3proto->tuple_to_nlattr(skb, tuple);
nla_nest_end(skb, nest_parms);
return ret;
nla_put_failure:
return -1;
}
static int
ctnetlink_dump_tuples(struct sk_buff *skb,
const struct nf_conntrack_tuple *tuple)
{
int ret;
struct nf_conntrack_l3proto *l3proto;
struct nf_conntrack_l4proto *l4proto;
l3proto = __nf_ct_l3proto_find(tuple->src.l3num);
ret = ctnetlink_dump_tuples_ip(skb, tuple, l3proto);
if (unlikely(ret < 0))
return ret;
l4proto = __nf_ct_l4proto_find(tuple->src.l3num, tuple->dst.protonum);
ret = ctnetlink_dump_tuples_proto(skb, tuple, l4proto);
return ret;
}
static inline int
ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct)
{
NLA_PUT_BE32(skb, CTA_STATUS, htonl(ct->status));
return 0;
nla_put_failure:
return -1;
}
static inline int
ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct)
{
long timeout = (ct->timeout.expires - jiffies) / HZ;
if (timeout < 0)
timeout = 0;
NLA_PUT_BE32(skb, CTA_TIMEOUT, htonl(timeout));
return 0;
nla_put_failure:
return -1;
}
static inline int
ctnetlink_dump_protoinfo(struct sk_buff *skb, struct nf_conn *ct)
{
struct nf_conntrack_l4proto *l4proto;
struct nlattr *nest_proto;
int ret;
l4proto = __nf_ct_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct));
if (!l4proto->to_nlattr)
return 0;
nest_proto = nla_nest_start(skb, CTA_PROTOINFO | NLA_F_NESTED);
if (!nest_proto)
goto nla_put_failure;
ret = l4proto->to_nlattr(skb, nest_proto, ct);
nla_nest_end(skb, nest_proto);
return ret;
nla_put_failure:
return -1;
}
static inline int
ctnetlink_dump_helpinfo(struct sk_buff *skb, const struct nf_conn *ct)
{
struct nlattr *nest_helper;
const struct nf_conn_help *help = nfct_help(ct);
struct nf_conntrack_helper *helper;
if (!help)
return 0;
helper = rcu_dereference(help->helper);
if (!helper)
goto out;
nest_helper = nla_nest_start(skb, CTA_HELP | NLA_F_NESTED);
if (!nest_helper)
goto nla_put_failure;
NLA_PUT_STRING(skb, CTA_HELP_NAME, helper->name);
if (helper->to_nlattr)
helper->to_nlattr(skb, ct);
nla_nest_end(skb, nest_helper);
out:
return 0;
nla_put_failure:
return -1;
}
static int
dump_counters(struct sk_buff *skb, u64 pkts, u64 bytes,
enum ip_conntrack_dir dir)
{
enum ctattr_type type = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
struct nlattr *nest_count;
nest_count = nla_nest_start(skb, type | NLA_F_NESTED);
if (!nest_count)
goto nla_put_failure;
NLA_PUT_BE64(skb, CTA_COUNTERS_PACKETS, cpu_to_be64(pkts));
NLA_PUT_BE64(skb, CTA_COUNTERS_BYTES, cpu_to_be64(bytes));
nla_nest_end(skb, nest_count);
return 0;
nla_put_failure:
return -1;
}
static int
ctnetlink_dump_counters(struct sk_buff *skb, const struct nf_conn *ct,
enum ip_conntrack_dir dir, int type)
{
struct nf_conn_counter *acct;
u64 pkts, bytes;
acct = nf_conn_acct_find(ct);
if (!acct)
return 0;
if (type == IPCTNL_MSG_CT_GET_CTRZERO) {
pkts = atomic64_xchg(&acct[dir].packets, 0);
bytes = atomic64_xchg(&acct[dir].bytes, 0);
} else {
pkts = atomic64_read(&acct[dir].packets);
bytes = atomic64_read(&acct[dir].bytes);
}
return dump_counters(skb, pkts, bytes, dir);
}
static int
ctnetlink_dump_timestamp(struct sk_buff *skb, const struct nf_conn *ct)
{
struct nlattr *nest_count;
const struct nf_conn_tstamp *tstamp;
tstamp = nf_conn_tstamp_find(ct);
if (!tstamp)
return 0;
nest_count = nla_nest_start(skb, CTA_TIMESTAMP | NLA_F_NESTED);
if (!nest_count)
goto nla_put_failure;
NLA_PUT_BE64(skb, CTA_TIMESTAMP_START, cpu_to_be64(tstamp->start));
if (tstamp->stop != 0) {
NLA_PUT_BE64(skb, CTA_TIMESTAMP_STOP,
cpu_to_be64(tstamp->stop));
}
nla_nest_end(skb, nest_count);
return 0;
nla_put_failure:
return -1;
}
#ifdef CONFIG_NF_CONNTRACK_MARK
static inline int
ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct)
{
NLA_PUT_BE32(skb, CTA_MARK, htonl(ct->mark));
return 0;
nla_put_failure:
return -1;
}
#else
#define ctnetlink_dump_mark(a, b) (0)
#endif
#ifdef CONFIG_NF_CONNTRACK_SECMARK
static inline int
ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
{
struct nlattr *nest_secctx;
int len, ret;
char *secctx;
ret = security_secid_to_secctx(ct->secmark, &secctx, &len);
if (ret)
return 0;
ret = -1;
nest_secctx = nla_nest_start(skb, CTA_SECCTX | NLA_F_NESTED);
if (!nest_secctx)
goto nla_put_failure;
NLA_PUT_STRING(skb, CTA_SECCTX_NAME, secctx);
nla_nest_end(skb, nest_secctx);
ret = 0;
nla_put_failure:
security_release_secctx(secctx, len);
return ret;
}
#else
#define ctnetlink_dump_secctx(a, b) (0)
#endif
#define master_tuple(ct) &(ct->master->tuplehash[IP_CT_DIR_ORIGINAL].tuple)
static inline int
ctnetlink_dump_master(struct sk_buff *skb, const struct nf_conn *ct)
{
struct nlattr *nest_parms;
if (!(ct->status & IPS_EXPECTED))
return 0;
nest_parms = nla_nest_start(skb, CTA_TUPLE_MASTER | NLA_F_NESTED);
if (!nest_parms)
goto nla_put_failure;
if (ctnetlink_dump_tuples(skb, master_tuple(ct)) < 0)
goto nla_put_failure;
nla_nest_end(skb, nest_parms);
return 0;
nla_put_failure:
return -1;
}
#ifdef CONFIG_NF_NAT_NEEDED
static int
dump_nat_seq_adj(struct sk_buff *skb, const struct nf_nat_seq *natseq, int type)
{
struct nlattr *nest_parms;
nest_parms = nla_nest_start(skb, type | NLA_F_NESTED);
if (!nest_parms)
goto nla_put_failure;
NLA_PUT_BE32(skb, CTA_NAT_SEQ_CORRECTION_POS,
htonl(natseq->correction_pos));
NLA_PUT_BE32(skb, CTA_NAT_SEQ_OFFSET_BEFORE,
htonl(natseq->offset_before));
NLA_PUT_BE32(skb, CTA_NAT_SEQ_OFFSET_AFTER,
htonl(natseq->offset_after));
nla_nest_end(skb, nest_parms);
return 0;
nla_put_failure:
return -1;
}
static inline int
ctnetlink_dump_nat_seq_adj(struct sk_buff *skb, const struct nf_conn *ct)
{
struct nf_nat_seq *natseq;
struct nf_conn_nat *nat = nfct_nat(ct);
if (!(ct->status & IPS_SEQ_ADJUST) || !nat)
return 0;
natseq = &nat->seq[IP_CT_DIR_ORIGINAL];
if (dump_nat_seq_adj(skb, natseq, CTA_NAT_SEQ_ADJ_ORIG) == -1)
return -1;
natseq = &nat->seq[IP_CT_DIR_REPLY];
if (dump_nat_seq_adj(skb, natseq, CTA_NAT_SEQ_ADJ_REPLY) == -1)
return -1;
return 0;
}
#else
#define ctnetlink_dump_nat_seq_adj(a, b) (0)
#endif
static inline int
ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct)
{
NLA_PUT_BE32(skb, CTA_ID, htonl((unsigned long)ct));
return 0;
nla_put_failure:
return -1;
}
static inline int
ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct)
{
NLA_PUT_BE32(skb, CTA_USE, htonl(atomic_read(&ct->ct_general.use)));
return 0;
nla_put_failure:
return -1;
}
static int
ctnetlink_fill_info(struct sk_buff *skb, u32 pid, u32 seq, u32 type,
struct nf_conn *ct)
{
struct nlmsghdr *nlh;
struct nfgenmsg *nfmsg;
struct nlattr *nest_parms;
unsigned int flags = pid ? NLM_F_MULTI : 0, event;
event = (NFNL_SUBSYS_CTNETLINK << 8 | IPCTNL_MSG_CT_NEW);
nlh = nlmsg_put(skb, pid, seq, event, sizeof(*nfmsg), flags);
if (nlh == NULL)
goto nlmsg_failure;
nfmsg = nlmsg_data(nlh);
nfmsg->nfgen_family = nf_ct_l3num(ct);
nfmsg->version = NFNETLINK_V0;
nfmsg->res_id = 0;
nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG | NLA_F_NESTED);
if (!nest_parms)
goto nla_put_failure;
if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
goto nla_put_failure;
nla_nest_end(skb, nest_parms);
nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY | NLA_F_NESTED);
if (!nest_parms)
goto nla_put_failure;
if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_REPLY)) < 0)
goto nla_put_failure;
nla_nest_end(skb, nest_parms);
if (nf_ct_zone(ct))
NLA_PUT_BE16(skb, CTA_ZONE, htons(nf_ct_zone(ct)));
if (ctnetlink_dump_status(skb, ct) < 0 ||
ctnetlink_dump_timeout(skb, ct) < 0 ||
ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL, type) < 0 ||
ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY, type) < 0 ||
ctnetlink_dump_timestamp(skb, ct) < 0 ||
ctnetlink_dump_protoinfo(skb, ct) < 0 ||
ctnetlink_dump_helpinfo(skb, ct) < 0 ||
ctnetlink_dump_mark(skb, ct) < 0 ||
ctnetlink_dump_secctx(skb, ct) < 0 ||
ctnetlink_dump_id(skb, ct) < 0 ||
ctnetlink_dump_use(skb, ct) < 0 ||
ctnetlink_dump_master(skb, ct) < 0 ||
ctnetlink_dump_nat_seq_adj(skb, ct) < 0)
goto nla_put_failure;
nlmsg_end(skb, nlh);
return skb->len;
nlmsg_failure:
nla_put_failure:
nlmsg_cancel(skb, nlh);
return -1;
}
#ifdef CONFIG_NF_CONNTRACK_EVENTS
static inline size_t
ctnetlink_proto_size(const struct nf_conn *ct)
{
struct nf_conntrack_l3proto *l3proto;
struct nf_conntrack_l4proto *l4proto;
size_t len = 0;
rcu_read_lock();
l3proto = __nf_ct_l3proto_find(nf_ct_l3num(ct));
len += l3proto->nla_size;
l4proto = __nf_ct_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct));
len += l4proto->nla_size;
rcu_read_unlock();
return len;
}
static inline size_t
ctnetlink_counters_size(const struct nf_conn *ct)
{
if (!nf_ct_ext_exist(ct, NF_CT_EXT_ACCT))
return 0;
return 2 * nla_total_size(0) /* CTA_COUNTERS_ORIG|REPL */
+ 2 * nla_total_size(sizeof(uint64_t)) /* CTA_COUNTERS_PACKETS */
+ 2 * nla_total_size(sizeof(uint64_t)) /* CTA_COUNTERS_BYTES */
;
}
static inline int
ctnetlink_secctx_size(const struct nf_conn *ct)
{
#ifdef CONFIG_NF_CONNTRACK_SECMARK
int len, ret;
ret = security_secid_to_secctx(ct->secmark, NULL, &len);
if (ret)
return 0;
return nla_total_size(0) /* CTA_SECCTX */
+ nla_total_size(sizeof(char) * len); /* CTA_SECCTX_NAME */
#else
return 0;
#endif
}
static inline size_t
ctnetlink_timestamp_size(const struct nf_conn *ct)
{
#ifdef CONFIG_NF_CONNTRACK_TIMESTAMP
if (!nf_ct_ext_exist(ct, NF_CT_EXT_TSTAMP))
return 0;
return nla_total_size(0) + 2 * nla_total_size(sizeof(uint64_t));
#else
return 0;
#endif
}
static inline size_t
ctnetlink_nlmsg_size(const struct nf_conn *ct)
{
return NLMSG_ALIGN(sizeof(struct nfgenmsg))
+ 3 * nla_total_size(0) /* CTA_TUPLE_ORIG|REPL|MASTER */
+ 3 * nla_total_size(0) /* CTA_TUPLE_IP */
+ 3 * nla_total_size(0) /* CTA_TUPLE_PROTO */
+ 3 * nla_total_size(sizeof(u_int8_t)) /* CTA_PROTO_NUM */
+ nla_total_size(sizeof(u_int32_t)) /* CTA_ID */
+ nla_total_size(sizeof(u_int32_t)) /* CTA_STATUS */
+ ctnetlink_counters_size(ct)
+ ctnetlink_timestamp_size(ct)
+ nla_total_size(sizeof(u_int32_t)) /* CTA_TIMEOUT */
+ nla_total_size(0) /* CTA_PROTOINFO */
+ nla_total_size(0) /* CTA_HELP */
+ nla_total_size(NF_CT_HELPER_NAME_LEN) /* CTA_HELP_NAME */
+ ctnetlink_secctx_size(ct)
#ifdef CONFIG_NF_NAT_NEEDED
+ 2 * nla_total_size(0) /* CTA_NAT_SEQ_ADJ_ORIG|REPL */
+ 6 * nla_total_size(sizeof(u_int32_t)) /* CTA_NAT_SEQ_OFFSET */
#endif
#ifdef CONFIG_NF_CONNTRACK_MARK
+ nla_total_size(sizeof(u_int32_t)) /* CTA_MARK */
#endif
+ ctnetlink_proto_size(ct)
;
}
static int
ctnetlink_conntrack_event(unsigned int events, struct nf_ct_event *item)
{
struct net *net;
struct nlmsghdr *nlh;
struct nfgenmsg *nfmsg;
struct nlattr *nest_parms;
struct nf_conn *ct = item->ct;
struct sk_buff *skb;
unsigned int type;
unsigned int flags = 0, group;
int err;
/* ignore our fake conntrack entry */
if (nf_ct_is_untracked(ct))
return 0;
if (events & (1 << IPCT_DESTROY)) {
type = IPCTNL_MSG_CT_DELETE;
group = NFNLGRP_CONNTRACK_DESTROY;
} else if (events & ((1 << IPCT_NEW) | (1 << IPCT_RELATED))) {
type = IPCTNL_MSG_CT_NEW;
flags = NLM_F_CREATE|NLM_F_EXCL;
group = NFNLGRP_CONNTRACK_NEW;
} else if (events) {
type = IPCTNL_MSG_CT_NEW;
group = NFNLGRP_CONNTRACK_UPDATE;
} else
return 0;
net = nf_ct_net(ct);
if (!item->report && !nfnetlink_has_listeners(net, group))
return 0;
skb = nlmsg_new(ctnetlink_nlmsg_size(ct), GFP_ATOMIC);
if (skb == NULL)
goto errout;
type |= NFNL_SUBSYS_CTNETLINK << 8;
nlh = nlmsg_put(skb, item->pid, 0, type, sizeof(*nfmsg), flags);
if (nlh == NULL)
goto nlmsg_failure;
nfmsg = nlmsg_data(nlh);
nfmsg->nfgen_family = nf_ct_l3num(ct);
nfmsg->version = NFNETLINK_V0;
nfmsg->res_id = 0;
rcu_read_lock();
nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG | NLA_F_NESTED);
if (!nest_parms)
goto nla_put_failure;
if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
goto nla_put_failure;
nla_nest_end(skb, nest_parms);
nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY | NLA_F_NESTED);
if (!nest_parms)
goto nla_put_failure;
if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_REPLY)) < 0)
goto nla_put_failure;
nla_nest_end(skb, nest_parms);
if (nf_ct_zone(ct))
NLA_PUT_BE16(skb, CTA_ZONE, htons(nf_ct_zone(ct)));
if (ctnetlink_dump_id(skb, ct) < 0)
goto nla_put_failure;
if (ctnetlink_dump_status(skb, ct) < 0)
goto nla_put_failure;
if (events & (1 << IPCT_DESTROY)) {
if (ctnetlink_dump_counters(skb, ct,
IP_CT_DIR_ORIGINAL, type) < 0 ||
ctnetlink_dump_counters(skb, ct,
IP_CT_DIR_REPLY, type) < 0 ||
ctnetlink_dump_timestamp(skb, ct) < 0)
goto nla_put_failure;
} else {
if (ctnetlink_dump_timeout(skb, ct) < 0)
goto nla_put_failure;
if (events & (1 << IPCT_PROTOINFO)
&& ctnetlink_dump_protoinfo(skb, ct) < 0)
goto nla_put_failure;
if ((events & (1 << IPCT_HELPER) || nfct_help(ct))
&& ctnetlink_dump_helpinfo(skb, ct) < 0)
goto nla_put_failure;
#ifdef CONFIG_NF_CONNTRACK_SECMARK
if ((events & (1 << IPCT_SECMARK) || ct->secmark)
&& ctnetlink_dump_secctx(skb, ct) < 0)
goto nla_put_failure;
#endif
if (events & (1 << IPCT_RELATED) &&
ctnetlink_dump_master(skb, ct) < 0)
goto nla_put_failure;
if (events & (1 << IPCT_NATSEQADJ) &&
ctnetlink_dump_nat_seq_adj(skb, ct) < 0)
goto nla_put_failure;
}
#ifdef CONFIG_NF_CONNTRACK_MARK
if ((events & (1 << IPCT_MARK) || ct->mark)
&& ctnetlink_dump_mark(skb, ct) < 0)
goto nla_put_failure;
#endif
rcu_read_unlock();
nlmsg_end(skb, nlh);
err = nfnetlink_send(skb, net, item->pid, group, item->report,
GFP_ATOMIC);
if (err == -ENOBUFS || err == -EAGAIN)
return -ENOBUFS;
return 0;
nla_put_failure:
rcu_read_unlock();
nlmsg_cancel(skb, nlh);
nlmsg_failure:
kfree_skb(skb);
errout:
if (nfnetlink_set_err(net, 0, group, -ENOBUFS) > 0)
return -ENOBUFS;
return 0;
}
#endif /* CONFIG_NF_CONNTRACK_EVENTS */
static int ctnetlink_done(struct netlink_callback *cb)
{
if (cb->args[1])
nf_ct_put((struct nf_conn *)cb->args[1]);
return 0;
}
static int
ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
{
struct net *net = sock_net(skb->sk);
struct nf_conn *ct, *last;
struct nf_conntrack_tuple_hash *h;
struct hlist_nulls_node *n;
struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
u_int8_t l3proto = nfmsg->nfgen_family;
spin_lock_bh(&nf_conntrack_lock);
last = (struct nf_conn *)cb->args[1];
for (; cb->args[0] < net->ct.htable_size; cb->args[0]++) {
restart:
hlist_nulls_for_each_entry(h, n, &net->ct.hash[cb->args[0]],
hnnode) {
if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL)
continue;
ct = nf_ct_tuplehash_to_ctrack(h);
/* Dump entries of a given L3 protocol number.
* If it is not specified, ie. l3proto == 0,
* then dump everything. */
if (l3proto && nf_ct_l3num(ct) != l3proto)
continue;
if (cb->args[1]) {
if (ct != last)
continue;
cb->args[1] = 0;
}
if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
cb->nlh->nlmsg_seq,
NFNL_MSG_TYPE(
cb->nlh->nlmsg_type),
ct) < 0) {
nf_conntrack_get(&ct->ct_general);
cb->args[1] = (unsigned long)ct;
goto out;
}
}
if (cb->args[1]) {
cb->args[1] = 0;
goto restart;
}
}
out:
spin_unlock_bh(&nf_conntrack_lock);
if (last)
nf_ct_put(last);
return skb->len;
}
static inline int
ctnetlink_parse_tuple_ip(struct nlattr *attr, struct nf_conntrack_tuple *tuple)
{
struct nlattr *tb[CTA_IP_MAX+1];
struct nf_conntrack_l3proto *l3proto;
int ret = 0;
nla_parse_nested(tb, CTA_IP_MAX, attr, NULL);
rcu_read_lock();
l3proto = __nf_ct_l3proto_find(tuple->src.l3num);
if (likely(l3proto->nlattr_to_tuple)) {
ret = nla_validate_nested(attr, CTA_IP_MAX,
l3proto->nla_policy);
if (ret == 0)
ret = l3proto->nlattr_to_tuple(tb, tuple);
}
rcu_read_unlock();
return ret;
}
static const struct nla_policy proto_nla_policy[CTA_PROTO_MAX+1] = {
[CTA_PROTO_NUM] = { .type = NLA_U8 },
};
static inline int
ctnetlink_parse_tuple_proto(struct nlattr *attr,
struct nf_conntrack_tuple *tuple)
{
struct nlattr *tb[CTA_PROTO_MAX+1];
struct nf_conntrack_l4proto *l4proto;
int ret = 0;
ret = nla_parse_nested(tb, CTA_PROTO_MAX, attr, proto_nla_policy);
if (ret < 0)
return ret;
if (!tb[CTA_PROTO_NUM])
return -EINVAL;
tuple->dst.protonum = nla_get_u8(tb[CTA_PROTO_NUM]);
rcu_read_lock();
l4proto = __nf_ct_l4proto_find(tuple->src.l3num, tuple->dst.protonum);
if (likely(l4proto->nlattr_to_tuple)) {
ret = nla_validate_nested(attr, CTA_PROTO_MAX,
l4proto->nla_policy);
if (ret == 0)
ret = l4proto->nlattr_to_tuple(tb, tuple);
}
rcu_read_unlock();
return ret;
}
static const struct nla_policy tuple_nla_policy[CTA_TUPLE_MAX+1] = {
[CTA_TUPLE_IP] = { .type = NLA_NESTED },
[CTA_TUPLE_PROTO] = { .type = NLA_NESTED },
};
static int
ctnetlink_parse_tuple(const struct nlattr * const cda[],
struct nf_conntrack_tuple *tuple,
enum ctattr_type type, u_int8_t l3num)
{
struct nlattr *tb[CTA_TUPLE_MAX+1];
int err;
memset(tuple, 0, sizeof(*tuple));
nla_parse_nested(tb, CTA_TUPLE_MAX, cda[type], tuple_nla_policy);
if (!tb[CTA_TUPLE_IP])
return -EINVAL;
tuple->src.l3num = l3num;
err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP], tuple);
if (err < 0)
return err;
if (!tb[CTA_TUPLE_PROTO])
return -EINVAL;
err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO], tuple);
if (err < 0)
return err;
/* orig and expect tuples get DIR_ORIGINAL */
if (type == CTA_TUPLE_REPLY)
tuple->dst.dir = IP_CT_DIR_REPLY;
else
tuple->dst.dir = IP_CT_DIR_ORIGINAL;
return 0;
}
static int
ctnetlink_parse_zone(const struct nlattr *attr, u16 *zone)
{
if (attr)
#ifdef CONFIG_NF_CONNTRACK_ZONES
*zone = ntohs(nla_get_be16(attr));
#else
return -EOPNOTSUPP;
#endif
else
*zone = 0;
return 0;
}
static const struct nla_policy help_nla_policy[CTA_HELP_MAX+1] = {
[CTA_HELP_NAME] = { .type = NLA_NUL_STRING },
};
static inline int
ctnetlink_parse_help(const struct nlattr *attr, char **helper_name)
{
struct nlattr *tb[CTA_HELP_MAX+1];
nla_parse_nested(tb, CTA_HELP_MAX, attr, help_nla_policy);
if (!tb[CTA_HELP_NAME])
return -EINVAL;
*helper_name = nla_data(tb[CTA_HELP_NAME]);
return 0;
}
static const struct nla_policy ct_nla_policy[CTA_MAX+1] = {
[CTA_TUPLE_ORIG] = { .type = NLA_NESTED },
[CTA_TUPLE_REPLY] = { .type = NLA_NESTED },
[CTA_STATUS] = { .type = NLA_U32 },
[CTA_PROTOINFO] = { .type = NLA_NESTED },
[CTA_HELP] = { .type = NLA_NESTED },
[CTA_NAT_SRC] = { .type = NLA_NESTED },
[CTA_TIMEOUT] = { .type = NLA_U32 },
[CTA_MARK] = { .type = NLA_U32 },
[CTA_ID] = { .type = NLA_U32 },
[CTA_NAT_DST] = { .type = NLA_NESTED },
[CTA_TUPLE_MASTER] = { .type = NLA_NESTED },
[CTA_ZONE] = { .type = NLA_U16 },
};
static int
ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const cda[])
{
struct net *net = sock_net(ctnl);
struct nf_conntrack_tuple_hash *h;
struct nf_conntrack_tuple tuple;
struct nf_conn *ct;
struct nfgenmsg *nfmsg = nlmsg_data(nlh);
u_int8_t u3 = nfmsg->nfgen_family;
u16 zone;
int err;
err = ctnetlink_parse_zone(cda[CTA_ZONE], &zone);
if (err < 0)
return err;
if (cda[CTA_TUPLE_ORIG])
err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
else if (cda[CTA_TUPLE_REPLY])
err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
else {
/* Flush the whole table */
nf_conntrack_flush_report(net,
NETLINK_CB(skb).pid,
nlmsg_report(nlh));
return 0;
}
if (err < 0)
return err;
h = nf_conntrack_find_get(net, zone, &tuple);
if (!h)
return -ENOENT;
ct = nf_ct_tuplehash_to_ctrack(h);
if (cda[CTA_ID]) {
u_int32_t id = ntohl(nla_get_be32(cda[CTA_ID]));
if (id != (u32)(unsigned long)ct) {
nf_ct_put(ct);
return -ENOENT;
}
}
if (nf_conntrack_event_report(IPCT_DESTROY, ct,
NETLINK_CB(skb).pid,
nlmsg_report(nlh)) < 0) {
nf_ct_delete_from_lists(ct);
/* we failed to report the event, try later */
nf_ct_insert_dying_list(ct);
nf_ct_put(ct);
return 0;
}
/* death_by_timeout would report the event again */
set_bit(IPS_DYING_BIT, &ct->status);
nf_ct_kill(ct);
nf_ct_put(ct);
return 0;
}
static int
ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const cda[])
{
struct net *net = sock_net(ctnl);
struct nf_conntrack_tuple_hash *h;
struct nf_conntrack_tuple tuple;
struct nf_conn *ct;
struct sk_buff *skb2 = NULL;
struct nfgenmsg *nfmsg = nlmsg_data(nlh);
u_int8_t u3 = nfmsg->nfgen_family;
u16 zone;
int err;
if (nlh->nlmsg_flags & NLM_F_DUMP)
return netlink_dump_start(ctnl, skb, nlh, ctnetlink_dump_table,
ctnetlink_done, 0);
err = ctnetlink_parse_zone(cda[CTA_ZONE], &zone);
if (err < 0)
return err;
if (cda[CTA_TUPLE_ORIG])
err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
else if (cda[CTA_TUPLE_REPLY])
err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
else
return -EINVAL;
if (err < 0)
return err;
h = nf_conntrack_find_get(net, zone, &tuple);
if (!h)
return -ENOENT;
ct = nf_ct_tuplehash_to_ctrack(h);
err = -ENOMEM;
skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
if (skb2 == NULL) {
nf_ct_put(ct);
return -ENOMEM;
}
rcu_read_lock();
err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,
NFNL_MSG_TYPE(nlh->nlmsg_type), ct);
rcu_read_unlock();
nf_ct_put(ct);
if (err <= 0)
goto free;
err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
if (err < 0)
goto out;
return 0;
free:
kfree_skb(skb2);
out:
/* this avoids a loop in nfnetlink. */
return err == -EAGAIN ? -ENOBUFS : err;
}
#ifdef CONFIG_NF_NAT_NEEDED
static int
ctnetlink_parse_nat_setup(struct nf_conn *ct,
enum nf_nat_manip_type manip,
const struct nlattr *attr)
{
typeof(nfnetlink_parse_nat_setup_hook) parse_nat_setup;
parse_nat_setup = rcu_dereference(nfnetlink_parse_nat_setup_hook);
if (!parse_nat_setup) {
#ifdef CONFIG_MODULES
rcu_read_unlock();
spin_unlock_bh(&nf_conntrack_lock);
nfnl_unlock();
if (request_module("nf-nat-ipv4") < 0) {
nfnl_lock();
spin_lock_bh(&nf_conntrack_lock);
rcu_read_lock();
return -EOPNOTSUPP;
}
nfnl_lock();
spin_lock_bh(&nf_conntrack_lock);
rcu_read_lock();
if (nfnetlink_parse_nat_setup_hook)
return -EAGAIN;
#endif
return -EOPNOTSUPP;
}
return parse_nat_setup(ct, manip, attr);
}
#endif
static int
ctnetlink_change_status(struct nf_conn *ct, const struct nlattr * const cda[])
{
unsigned long d;
unsigned int status = ntohl(nla_get_be32(cda[CTA_STATUS]));
d = ct->status ^ status;
if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
/* unchangeable */
return -EBUSY;
if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
/* SEEN_REPLY bit can only be set */
return -EBUSY;
if (d & IPS_ASSURED && !(status & IPS_ASSURED))
/* ASSURED bit can only be set */
return -EBUSY;
/* Be careful here, modifying NAT bits can screw up things,
* so don't let users modify them directly if they don't pass
* nf_nat_range. */
ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK);
return 0;
}
static int
ctnetlink_change_nat(struct nf_conn *ct, const struct nlattr * const cda[])
{
#ifdef CONFIG_NF_NAT_NEEDED
int ret;
if (cda[CTA_NAT_DST]) {
ret = ctnetlink_parse_nat_setup(ct,
NF_NAT_MANIP_DST,
cda[CTA_NAT_DST]);
if (ret < 0)
return ret;
}
if (cda[CTA_NAT_SRC]) {
ret = ctnetlink_parse_nat_setup(ct,
NF_NAT_MANIP_SRC,
cda[CTA_NAT_SRC]);
if (ret < 0)
return ret;
}
return 0;
#else
return -EOPNOTSUPP;
#endif
}
static inline int
ctnetlink_change_helper(struct nf_conn *ct, const struct nlattr * const cda[])
{
struct nf_conntrack_helper *helper;
struct nf_conn_help *help = nfct_help(ct);
char *helpname = NULL;
int err;
/* don't change helper of sibling connections */
if (ct->master)
return -EBUSY;
err = ctnetlink_parse_help(cda[CTA_HELP], &helpname);
if (err < 0)
return err;
if (!strcmp(helpname, "")) {
if (help && help->helper) {
/* we had a helper before ... */
nf_ct_remove_expectations(ct);
RCU_INIT_POINTER(help->helper, NULL);
}
return 0;
}
helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct),
nf_ct_protonum(ct));
if (helper == NULL) {
#ifdef CONFIG_MODULES
spin_unlock_bh(&nf_conntrack_lock);
if (request_module("nfct-helper-%s", helpname) < 0) {
spin_lock_bh(&nf_conntrack_lock);
return -EOPNOTSUPP;
}
spin_lock_bh(&nf_conntrack_lock);
helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct),
nf_ct_protonum(ct));
if (helper)
return -EAGAIN;
#endif
return -EOPNOTSUPP;
}
if (help) {
if (help->helper == helper)
return 0;
if (help->helper)
return -EBUSY;
/* need to zero data of old helper */
memset(&help->help, 0, sizeof(help->help));
} else {
/* we cannot set a helper for an existing conntrack */
return -EOPNOTSUPP;
}
RCU_INIT_POINTER(help->helper, helper);
return 0;
}
static inline int
ctnetlink_change_timeout(struct nf_conn *ct, const struct nlattr * const cda[])
{
u_int32_t timeout = ntohl(nla_get_be32(cda[CTA_TIMEOUT]));
if (!del_timer(&ct->timeout))
return -ETIME;
ct->timeout.expires = jiffies + timeout * HZ;
add_timer(&ct->timeout);
return 0;
}
static const struct nla_policy protoinfo_policy[CTA_PROTOINFO_MAX+1] = {
[CTA_PROTOINFO_TCP] = { .type = NLA_NESTED },
[CTA_PROTOINFO_DCCP] = { .type = NLA_NESTED },
[CTA_PROTOINFO_SCTP] = { .type = NLA_NESTED },
};
static inline int
ctnetlink_change_protoinfo(struct nf_conn *ct, const struct nlattr * const cda[])
{
const struct nlattr *attr = cda[CTA_PROTOINFO];
struct nlattr *tb[CTA_PROTOINFO_MAX+1];
struct nf_conntrack_l4proto *l4proto;
int err = 0;
nla_parse_nested(tb, CTA_PROTOINFO_MAX, attr, protoinfo_policy);
rcu_read_lock();
l4proto = __nf_ct_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct));
if (l4proto->from_nlattr)
err = l4proto->from_nlattr(tb, ct);
rcu_read_unlock();
return err;
}
#ifdef CONFIG_NF_NAT_NEEDED
static const struct nla_policy nat_seq_policy[CTA_NAT_SEQ_MAX+1] = {
[CTA_NAT_SEQ_CORRECTION_POS] = { .type = NLA_U32 },
[CTA_NAT_SEQ_OFFSET_BEFORE] = { .type = NLA_U32 },
[CTA_NAT_SEQ_OFFSET_AFTER] = { .type = NLA_U32 },
};
static inline int
change_nat_seq_adj(struct nf_nat_seq *natseq, const struct nlattr * const attr)
{
struct nlattr *cda[CTA_NAT_SEQ_MAX+1];
nla_parse_nested(cda, CTA_NAT_SEQ_MAX, attr, nat_seq_policy);
if (!cda[CTA_NAT_SEQ_CORRECTION_POS])
return -EINVAL;
natseq->correction_pos =
ntohl(nla_get_be32(cda[CTA_NAT_SEQ_CORRECTION_POS]));
if (!cda[CTA_NAT_SEQ_OFFSET_BEFORE])
return -EINVAL;
natseq->offset_before =
ntohl(nla_get_be32(cda[CTA_NAT_SEQ_OFFSET_BEFORE]));
if (!cda[CTA_NAT_SEQ_OFFSET_AFTER])
return -EINVAL;
natseq->offset_after =
ntohl(nla_get_be32(cda[CTA_NAT_SEQ_OFFSET_AFTER]));
return 0;
}
static int
ctnetlink_change_nat_seq_adj(struct nf_conn *ct,
const struct nlattr * const cda[])
{
int ret = 0;
struct nf_conn_nat *nat = nfct_nat(ct);
if (!nat)
return 0;
if (cda[CTA_NAT_SEQ_ADJ_ORIG]) {
ret = change_nat_seq_adj(&nat->seq[IP_CT_DIR_ORIGINAL],
cda[CTA_NAT_SEQ_ADJ_ORIG]);
if (ret < 0)
return ret;
ct->status |= IPS_SEQ_ADJUST;
}
if (cda[CTA_NAT_SEQ_ADJ_REPLY]) {
ret = change_nat_seq_adj(&nat->seq[IP_CT_DIR_REPLY],
cda[CTA_NAT_SEQ_ADJ_REPLY]);
if (ret < 0)
return ret;
ct->status |= IPS_SEQ_ADJUST;
}
return 0;
}
#endif
static int
ctnetlink_change_conntrack(struct nf_conn *ct,
const struct nlattr * const cda[])
{
int err;
/* only allow NAT changes and master assignation for new conntracks */
if (cda[CTA_NAT_SRC] || cda[CTA_NAT_DST] || cda[CTA_TUPLE_MASTER])
return -EOPNOTSUPP;
if (cda[CTA_HELP]) {
err = ctnetlink_change_helper(ct, cda);
if (err < 0)
return err;
}
if (cda[CTA_TIMEOUT]) {
err = ctnetlink_change_timeout(ct, cda);
if (err < 0)
return err;
}
if (cda[CTA_STATUS]) {
err = ctnetlink_change_status(ct, cda);
if (err < 0)
return err;
}
if (cda[CTA_PROTOINFO]) {
err = ctnetlink_change_protoinfo(ct, cda);
if (err < 0)
return err;
}
#if defined(CONFIG_NF_CONNTRACK_MARK)
if (cda[CTA_MARK])
ct->mark = ntohl(nla_get_be32(cda[CTA_MARK]));
#endif
#ifdef CONFIG_NF_NAT_NEEDED
if (cda[CTA_NAT_SEQ_ADJ_ORIG] || cda[CTA_NAT_SEQ_ADJ_REPLY]) {
err = ctnetlink_change_nat_seq_adj(ct, cda);
if (err < 0)
return err;
}
#endif
return 0;
}
static struct nf_conn *
ctnetlink_create_conntrack(struct net *net, u16 zone,
const struct nlattr * const cda[],
struct nf_conntrack_tuple *otuple,
struct nf_conntrack_tuple *rtuple,
u8 u3)
{
struct nf_conn *ct;
int err = -EINVAL;
struct nf_conntrack_helper *helper;
struct nf_conn_tstamp *tstamp;
ct = nf_conntrack_alloc(net, zone, otuple, rtuple, GFP_ATOMIC);
if (IS_ERR(ct))
return ERR_PTR(-ENOMEM);
if (!cda[CTA_TIMEOUT])
goto err1;
ct->timeout.expires = ntohl(nla_get_be32(cda[CTA_TIMEOUT]));
ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
rcu_read_lock();
if (cda[CTA_HELP]) {
char *helpname = NULL;
err = ctnetlink_parse_help(cda[CTA_HELP], &helpname);
if (err < 0)
goto err2;
helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct),
nf_ct_protonum(ct));
if (helper == NULL) {
rcu_read_unlock();
#ifdef CONFIG_MODULES
if (request_module("nfct-helper-%s", helpname) < 0) {
err = -EOPNOTSUPP;
goto err1;
}
rcu_read_lock();
helper = __nf_conntrack_helper_find(helpname,
nf_ct_l3num(ct),
nf_ct_protonum(ct));
if (helper) {
err = -EAGAIN;
goto err2;
}
rcu_read_unlock();
#endif
err = -EOPNOTSUPP;
goto err1;
} else {
struct nf_conn_help *help;
help = nf_ct_helper_ext_add(ct, GFP_ATOMIC);
if (help == NULL) {
err = -ENOMEM;
goto err2;
}
/* not in hash table yet so not strictly necessary */
RCU_INIT_POINTER(help->helper, helper);
}
} else {
/* try an implicit helper assignation */
err = __nf_ct_try_assign_helper(ct, NULL, GFP_ATOMIC);
if (err < 0)
goto err2;
}
if (cda[CTA_NAT_SRC] || cda[CTA_NAT_DST]) {
err = ctnetlink_change_nat(ct, cda);
if (err < 0)
goto err2;
}
nf_ct_acct_ext_add(ct, GFP_ATOMIC);
nf_ct_tstamp_ext_add(ct, GFP_ATOMIC);
nf_ct_ecache_ext_add(ct, 0, 0, GFP_ATOMIC);
/* we must add conntrack extensions before confirmation. */
ct->status |= IPS_CONFIRMED;
if (cda[CTA_STATUS]) {
err = ctnetlink_change_status(ct, cda);
if (err < 0)
goto err2;
}
#ifdef CONFIG_NF_NAT_NEEDED
if (cda[CTA_NAT_SEQ_ADJ_ORIG] || cda[CTA_NAT_SEQ_ADJ_REPLY]) {
err = ctnetlink_change_nat_seq_adj(ct, cda);
if (err < 0)
goto err2;
}
#endif
memset(&ct->proto, 0, sizeof(ct->proto));
if (cda[CTA_PROTOINFO]) {
err = ctnetlink_change_protoinfo(ct, cda);
if (err < 0)
goto err2;
}
#if defined(CONFIG_NF_CONNTRACK_MARK)
if (cda[CTA_MARK])
ct->mark = ntohl(nla_get_be32(cda[CTA_MARK]));
#endif
/* setup master conntrack: this is a confirmed expectation */
if (cda[CTA_TUPLE_MASTER]) {
struct nf_conntrack_tuple master;
struct nf_conntrack_tuple_hash *master_h;
struct nf_conn *master_ct;
err = ctnetlink_parse_tuple(cda, &master, CTA_TUPLE_MASTER, u3);
if (err < 0)
goto err2;
master_h = nf_conntrack_find_get(net, zone, &master);
if (master_h == NULL) {
err = -ENOENT;
goto err2;
}
master_ct = nf_ct_tuplehash_to_ctrack(master_h);
__set_bit(IPS_EXPECTED_BIT, &ct->status);
ct->master = master_ct;
}
tstamp = nf_conn_tstamp_find(ct);
if (tstamp)
tstamp->start = ktime_to_ns(ktime_get_real());
add_timer(&ct->timeout);
nf_conntrack_hash_insert(ct);
rcu_read_unlock();
return ct;
err2:
rcu_read_unlock();
err1:
nf_conntrack_free(ct);
return ERR_PTR(err);
}
static int
ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const cda[])
{
struct net *net = sock_net(ctnl);
struct nf_conntrack_tuple otuple, rtuple;
struct nf_conntrack_tuple_hash *h = NULL;
struct nfgenmsg *nfmsg = nlmsg_data(nlh);
u_int8_t u3 = nfmsg->nfgen_family;
u16 zone;
int err;
err = ctnetlink_parse_zone(cda[CTA_ZONE], &zone);
if (err < 0)
return err;
if (cda[CTA_TUPLE_ORIG]) {
err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3);
if (err < 0)
return err;
}
if (cda[CTA_TUPLE_REPLY]) {
err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3);
if (err < 0)
return err;
}
spin_lock_bh(&nf_conntrack_lock);
if (cda[CTA_TUPLE_ORIG])
h = __nf_conntrack_find(net, zone, &otuple);
else if (cda[CTA_TUPLE_REPLY])
h = __nf_conntrack_find(net, zone, &rtuple);
if (h == NULL) {
err = -ENOENT;
if (nlh->nlmsg_flags & NLM_F_CREATE) {
struct nf_conn *ct;
enum ip_conntrack_events events;
ct = ctnetlink_create_conntrack(net, zone, cda, &otuple,
&rtuple, u3);
if (IS_ERR(ct)) {
err = PTR_ERR(ct);
goto out_unlock;
}
err = 0;
nf_conntrack_get(&ct->ct_general);
spin_unlock_bh(&nf_conntrack_lock);
if (test_bit(IPS_EXPECTED_BIT, &ct->status))
events = IPCT_RELATED;
else
events = IPCT_NEW;
nf_conntrack_eventmask_report((1 << IPCT_REPLY) |
(1 << IPCT_ASSURED) |
(1 << IPCT_HELPER) |
(1 << IPCT_PROTOINFO) |
(1 << IPCT_NATSEQADJ) |
(1 << IPCT_MARK) | events,
ct, NETLINK_CB(skb).pid,
nlmsg_report(nlh));
nf_ct_put(ct);
} else
spin_unlock_bh(&nf_conntrack_lock);
return err;
}
/* implicit 'else' */
/* We manipulate the conntrack inside the global conntrack table lock,
* so there's no need to increase the refcount */
err = -EEXIST;
if (!(nlh->nlmsg_flags & NLM_F_EXCL)) {
struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h);
err = ctnetlink_change_conntrack(ct, cda);
if (err == 0) {
nf_conntrack_get(&ct->ct_general);
spin_unlock_bh(&nf_conntrack_lock);
nf_conntrack_eventmask_report((1 << IPCT_REPLY) |
(1 << IPCT_ASSURED) |
(1 << IPCT_HELPER) |
(1 << IPCT_PROTOINFO) |
(1 << IPCT_NATSEQADJ) |
(1 << IPCT_MARK),
ct, NETLINK_CB(skb).pid,
nlmsg_report(nlh));
nf_ct_put(ct);
} else
spin_unlock_bh(&nf_conntrack_lock);
return err;
}
out_unlock:
spin_unlock_bh(&nf_conntrack_lock);
return err;
}
/***********************************************************************
* EXPECT
***********************************************************************/
static inline int
ctnetlink_exp_dump_tuple(struct sk_buff *skb,
const struct nf_conntrack_tuple *tuple,
enum ctattr_expect type)
{
struct nlattr *nest_parms;
nest_parms = nla_nest_start(skb, type | NLA_F_NESTED);
if (!nest_parms)
goto nla_put_failure;
if (ctnetlink_dump_tuples(skb, tuple) < 0)
goto nla_put_failure;
nla_nest_end(skb, nest_parms);
return 0;
nla_put_failure:
return -1;
}
static inline int
ctnetlink_exp_dump_mask(struct sk_buff *skb,
const struct nf_conntrack_tuple *tuple,
const struct nf_conntrack_tuple_mask *mask)
{
int ret;
struct nf_conntrack_l3proto *l3proto;
struct nf_conntrack_l4proto *l4proto;
struct nf_conntrack_tuple m;
struct nlattr *nest_parms;
memset(&m, 0xFF, sizeof(m));
memcpy(&m.src.u3, &mask->src.u3, sizeof(m.src.u3));
m.src.u.all = mask->src.u.all;
m.dst.protonum = tuple->dst.protonum;
nest_parms = nla_nest_start(skb, CTA_EXPECT_MASK | NLA_F_NESTED);
if (!nest_parms)
goto nla_put_failure;
l3proto = __nf_ct_l3proto_find(tuple->src.l3num);
ret = ctnetlink_dump_tuples_ip(skb, &m, l3proto);
if (unlikely(ret < 0))
goto nla_put_failure;
l4proto = __nf_ct_l4proto_find(tuple->src.l3num, tuple->dst.protonum);
ret = ctnetlink_dump_tuples_proto(skb, &m, l4proto);
if (unlikely(ret < 0))
goto nla_put_failure;
nla_nest_end(skb, nest_parms);
return 0;
nla_put_failure:
return -1;
}
static int
ctnetlink_exp_dump_expect(struct sk_buff *skb,
const struct nf_conntrack_expect *exp)
{
struct nf_conn *master = exp->master;
long timeout = (exp->timeout.expires - jiffies) / HZ;
struct nf_conn_help *help;
if (timeout < 0)
timeout = 0;
if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
goto nla_put_failure;
if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
goto nla_put_failure;
if (ctnetlink_exp_dump_tuple(skb,
&master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
CTA_EXPECT_MASTER) < 0)
goto nla_put_failure;
NLA_PUT_BE32(skb, CTA_EXPECT_TIMEOUT, htonl(timeout));
NLA_PUT_BE32(skb, CTA_EXPECT_ID, htonl((unsigned long)exp));
NLA_PUT_BE32(skb, CTA_EXPECT_FLAGS, htonl(exp->flags));
help = nfct_help(master);
if (help) {
struct nf_conntrack_helper *helper;
helper = rcu_dereference(help->helper);
if (helper)
NLA_PUT_STRING(skb, CTA_EXPECT_HELP_NAME, helper->name);
}
return 0;
nla_put_failure:
return -1;
}
static int
ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
int event, const struct nf_conntrack_expect *exp)
{
struct nlmsghdr *nlh;
struct nfgenmsg *nfmsg;
unsigned int flags = pid ? NLM_F_MULTI : 0;
event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
nlh = nlmsg_put(skb, pid, seq, event, sizeof(*nfmsg), flags);
if (nlh == NULL)
goto nlmsg_failure;
nfmsg = nlmsg_data(nlh);
nfmsg->nfgen_family = exp->tuple.src.l3num;
nfmsg->version = NFNETLINK_V0;
nfmsg->res_id = 0;
if (ctnetlink_exp_dump_expect(skb, exp) < 0)
goto nla_put_failure;
nlmsg_end(skb, nlh);
return skb->len;
nlmsg_failure:
nla_put_failure:
nlmsg_cancel(skb, nlh);
return -1;
}
#ifdef CONFIG_NF_CONNTRACK_EVENTS
static int
ctnetlink_expect_event(unsigned int events, struct nf_exp_event *item)
{
struct nf_conntrack_expect *exp = item->exp;
struct net *net = nf_ct_exp_net(exp);
struct nlmsghdr *nlh;
struct nfgenmsg *nfmsg;
struct sk_buff *skb;
unsigned int type, group;
int flags = 0;
if (events & (1 << IPEXP_DESTROY)) {
type = IPCTNL_MSG_EXP_DELETE;
group = NFNLGRP_CONNTRACK_EXP_DESTROY;
} else if (events & (1 << IPEXP_NEW)) {
type = IPCTNL_MSG_EXP_NEW;
flags = NLM_F_CREATE|NLM_F_EXCL;
group = NFNLGRP_CONNTRACK_EXP_NEW;
} else
return 0;
if (!item->report && !nfnetlink_has_listeners(net, group))
return 0;
skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
if (skb == NULL)
goto errout;
type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
nlh = nlmsg_put(skb, item->pid, 0, type, sizeof(*nfmsg), flags);
if (nlh == NULL)
goto nlmsg_failure;
nfmsg = nlmsg_data(nlh);
nfmsg->nfgen_family = exp->tuple.src.l3num;
nfmsg->version = NFNETLINK_V0;
nfmsg->res_id = 0;
rcu_read_lock();
if (ctnetlink_exp_dump_expect(skb, exp) < 0)
goto nla_put_failure;
rcu_read_unlock();
nlmsg_end(skb, nlh);
nfnetlink_send(skb, net, item->pid, group, item->report, GFP_ATOMIC);
return 0;
nla_put_failure:
rcu_read_unlock();
nlmsg_cancel(skb, nlh);
nlmsg_failure:
kfree_skb(skb);
errout:
nfnetlink_set_err(net, 0, 0, -ENOBUFS);
return 0;
}
#endif
static int ctnetlink_exp_done(struct netlink_callback *cb)
{
if (cb->args[1])
nf_ct_expect_put((struct nf_conntrack_expect *)cb->args[1]);
return 0;
}
static int
ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
{
struct net *net = sock_net(skb->sk);
struct nf_conntrack_expect *exp, *last;
struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
struct hlist_node *n;
u_int8_t l3proto = nfmsg->nfgen_family;
rcu_read_lock();
last = (struct nf_conntrack_expect *)cb->args[1];
for (; cb->args[0] < nf_ct_expect_hsize; cb->args[0]++) {
restart:
hlist_for_each_entry(exp, n, &net->ct.expect_hash[cb->args[0]],
hnode) {
if (l3proto && exp->tuple.src.l3num != l3proto)
continue;
if (cb->args[1]) {
if (exp != last)
continue;
cb->args[1] = 0;
}
if (ctnetlink_exp_fill_info(skb,
NETLINK_CB(cb->skb).pid,
cb->nlh->nlmsg_seq,
IPCTNL_MSG_EXP_NEW,
exp) < 0) {
if (!atomic_inc_not_zero(&exp->use))
continue;
cb->args[1] = (unsigned long)exp;
goto out;
}
}
if (cb->args[1]) {
cb->args[1] = 0;
goto restart;
}
}
out:
rcu_read_unlock();
if (last)
nf_ct_expect_put(last);
return skb->len;
}
static const struct nla_policy exp_nla_policy[CTA_EXPECT_MAX+1] = {
[CTA_EXPECT_MASTER] = { .type = NLA_NESTED },
[CTA_EXPECT_TUPLE] = { .type = NLA_NESTED },
[CTA_EXPECT_MASK] = { .type = NLA_NESTED },
[CTA_EXPECT_TIMEOUT] = { .type = NLA_U32 },
[CTA_EXPECT_ID] = { .type = NLA_U32 },
[CTA_EXPECT_HELP_NAME] = { .type = NLA_NUL_STRING },
[CTA_EXPECT_ZONE] = { .type = NLA_U16 },
[CTA_EXPECT_FLAGS] = { .type = NLA_U32 },
};
static int
ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const cda[])
{
struct net *net = sock_net(ctnl);
struct nf_conntrack_tuple tuple;
struct nf_conntrack_expect *exp;
struct sk_buff *skb2;
struct nfgenmsg *nfmsg = nlmsg_data(nlh);
u_int8_t u3 = nfmsg->nfgen_family;
u16 zone;
int err;
if (nlh->nlmsg_flags & NLM_F_DUMP) {
return netlink_dump_start(ctnl, skb, nlh,
ctnetlink_exp_dump_table,
ctnetlink_exp_done, 0);
}
err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
if (err < 0)
return err;
if (cda[CTA_EXPECT_TUPLE])
err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
else if (cda[CTA_EXPECT_MASTER])
err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);
else
return -EINVAL;
if (err < 0)
return err;
exp = nf_ct_expect_find_get(net, zone, &tuple);
if (!exp)
return -ENOENT;
if (cda[CTA_EXPECT_ID]) {
__be32 id = nla_get_be32(cda[CTA_EXPECT_ID]);
if (ntohl(id) != (u32)(unsigned long)exp) {
nf_ct_expect_put(exp);
return -ENOENT;
}
}
err = -ENOMEM;
skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
if (skb2 == NULL)
goto out;
rcu_read_lock();
err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW, exp);
rcu_read_unlock();
if (err <= 0)
goto free;
nf_ct_expect_put(exp);
return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
free:
kfree_skb(skb2);
out:
nf_ct_expect_put(exp);
return err;
}
static int
ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const cda[])
{
struct net *net = sock_net(ctnl);
struct nf_conntrack_expect *exp;
struct nf_conntrack_tuple tuple;
struct nfgenmsg *nfmsg = nlmsg_data(nlh);
struct hlist_node *n, *next;
u_int8_t u3 = nfmsg->nfgen_family;
unsigned int i;
u16 zone;
int err;
if (cda[CTA_EXPECT_TUPLE]) {
/* delete a single expect by tuple */
err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
if (err < 0)
return err;
err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
if (err < 0)
return err;
/* bump usage count to 2 */
exp = nf_ct_expect_find_get(net, zone, &tuple);
if (!exp)
return -ENOENT;
if (cda[CTA_EXPECT_ID]) {
__be32 id = nla_get_be32(cda[CTA_EXPECT_ID]);
if (ntohl(id) != (u32)(unsigned long)exp) {
nf_ct_expect_put(exp);
return -ENOENT;
}
}
/* after list removal, usage count == 1 */
spin_lock_bh(&nf_conntrack_lock);
if (del_timer(&exp->timeout)) {
nf_ct_unlink_expect_report(exp, NETLINK_CB(skb).pid,
nlmsg_report(nlh));
nf_ct_expect_put(exp);
}
spin_unlock_bh(&nf_conntrack_lock);
/* have to put what we 'get' above.
* after this line usage count == 0 */
nf_ct_expect_put(exp);
} else if (cda[CTA_EXPECT_HELP_NAME]) {
char *name = nla_data(cda[CTA_EXPECT_HELP_NAME]);
struct nf_conn_help *m_help;
/* delete all expectations for this helper */
spin_lock_bh(&nf_conntrack_lock);
for (i = 0; i < nf_ct_expect_hsize; i++) {
hlist_for_each_entry_safe(exp, n, next,
&net->ct.expect_hash[i],
hnode) {
m_help = nfct_help(exp->master);
if (!strcmp(m_help->helper->name, name) &&
del_timer(&exp->timeout)) {
nf_ct_unlink_expect_report(exp,
NETLINK_CB(skb).pid,
nlmsg_report(nlh));
nf_ct_expect_put(exp);
}
}
}
spin_unlock_bh(&nf_conntrack_lock);
} else {
/* This basically means we have to flush everything*/
spin_lock_bh(&nf_conntrack_lock);
for (i = 0; i < nf_ct_expect_hsize; i++) {
hlist_for_each_entry_safe(exp, n, next,
&net->ct.expect_hash[i],
hnode) {
if (del_timer(&exp->timeout)) {
nf_ct_unlink_expect_report(exp,
NETLINK_CB(skb).pid,
nlmsg_report(nlh));
nf_ct_expect_put(exp);
}
}
}
spin_unlock_bh(&nf_conntrack_lock);
}
return 0;
}
static int
ctnetlink_change_expect(struct nf_conntrack_expect *x,
const struct nlattr * const cda[])
{
return -EOPNOTSUPP;
}
static int
ctnetlink_create_expect(struct net *net, u16 zone,
const struct nlattr * const cda[],
u_int8_t u3,
u32 pid, int report)
{
struct nf_conntrack_tuple tuple, mask, master_tuple;
struct nf_conntrack_tuple_hash *h = NULL;
struct nf_conntrack_expect *exp;
struct nf_conn *ct;
struct nf_conn_help *help;
int err = 0;
/* caller guarantees that those three CTA_EXPECT_* exist */
err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
if (err < 0)
return err;
err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3);
if (err < 0)
return err;
err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3);
if (err < 0)
return err;
/* Look for master conntrack of this expectation */
h = nf_conntrack_find_get(net, zone, &master_tuple);
if (!h)
return -ENOENT;
ct = nf_ct_tuplehash_to_ctrack(h);
exp = nf_ct_expect_alloc(ct);
if (!exp) {
err = -ENOMEM;
goto out;
}
help = nfct_help(ct);
if (!help) {
err = -EOPNOTSUPP;
goto out;
}
if (test_bit(IPS_USERSPACE_HELPER_BIT, &ct->status)) {
if (!cda[CTA_EXPECT_TIMEOUT]) {
err = -EINVAL;
goto out;
}
exp->timeout.expires =
jiffies + ntohl(nla_get_be32(cda[CTA_EXPECT_TIMEOUT])) * HZ;
exp->flags = NF_CT_EXPECT_USERSPACE;
if (cda[CTA_EXPECT_FLAGS]) {
exp->flags |=
ntohl(nla_get_be32(cda[CTA_EXPECT_FLAGS]));
}
} else {
if (cda[CTA_EXPECT_FLAGS]) {
exp->flags = ntohl(nla_get_be32(cda[CTA_EXPECT_FLAGS]));
exp->flags &= ~NF_CT_EXPECT_USERSPACE;
} else
exp->flags = 0;
}
exp->class = 0;
exp->expectfn = NULL;
exp->master = ct;
exp->helper = NULL;
memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));
memcpy(&exp->mask.src.u3, &mask.src.u3, sizeof(exp->mask.src.u3));
exp->mask.src.u.all = mask.src.u.all;
err = nf_ct_expect_related_report(exp, pid, report);
nf_ct_expect_put(exp);
out:
nf_ct_put(nf_ct_tuplehash_to_ctrack(h));
return err;
}
static int
ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
const struct nlmsghdr *nlh,
const struct nlattr * const cda[])
{
struct net *net = sock_net(ctnl);
struct nf_conntrack_tuple tuple;
struct nf_conntrack_expect *exp;
struct nfgenmsg *nfmsg = nlmsg_data(nlh);
u_int8_t u3 = nfmsg->nfgen_family;
u16 zone;
int err;
if (!cda[CTA_EXPECT_TUPLE]
|| !cda[CTA_EXPECT_MASK]
|| !cda[CTA_EXPECT_MASTER])
return -EINVAL;
err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
if (err < 0)
return err;
err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
if (err < 0)
return err;
spin_lock_bh(&nf_conntrack_lock);
exp = __nf_ct_expect_find(net, zone, &tuple);
if (!exp) {
spin_unlock_bh(&nf_conntrack_lock);
err = -ENOENT;
if (nlh->nlmsg_flags & NLM_F_CREATE) {
err = ctnetlink_create_expect(net, zone, cda,
u3,
NETLINK_CB(skb).pid,
nlmsg_report(nlh));
}
return err;
}
err = -EEXIST;
if (!(nlh->nlmsg_flags & NLM_F_EXCL))
err = ctnetlink_change_expect(exp, cda);
spin_unlock_bh(&nf_conntrack_lock);
return err;
}
#ifdef CONFIG_NF_CONNTRACK_EVENTS
static struct nf_ct_event_notifier ctnl_notifier = {
.fcn = ctnetlink_conntrack_event,
};
static struct nf_exp_event_notifier ctnl_notifier_exp = {
.fcn = ctnetlink_expect_event,
};
#endif
static const struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
[IPCTNL_MSG_CT_NEW] = { .call = ctnetlink_new_conntrack,
.attr_count = CTA_MAX,
.policy = ct_nla_policy },
[IPCTNL_MSG_CT_GET] = { .call = ctnetlink_get_conntrack,
.attr_count = CTA_MAX,
.policy = ct_nla_policy },
[IPCTNL_MSG_CT_DELETE] = { .call = ctnetlink_del_conntrack,
.attr_count = CTA_MAX,
.policy = ct_nla_policy },
[IPCTNL_MSG_CT_GET_CTRZERO] = { .call = ctnetlink_get_conntrack,
.attr_count = CTA_MAX,
.policy = ct_nla_policy },
};
static const struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
[IPCTNL_MSG_EXP_GET] = { .call = ctnetlink_get_expect,
.attr_count = CTA_EXPECT_MAX,
.policy = exp_nla_policy },
[IPCTNL_MSG_EXP_NEW] = { .call = ctnetlink_new_expect,
.attr_count = CTA_EXPECT_MAX,
.policy = exp_nla_policy },
[IPCTNL_MSG_EXP_DELETE] = { .call = ctnetlink_del_expect,
.attr_count = CTA_EXPECT_MAX,
.policy = exp_nla_policy },
};
static const struct nfnetlink_subsystem ctnl_subsys = {
.name = "conntrack",
.subsys_id = NFNL_SUBSYS_CTNETLINK,
.cb_count = IPCTNL_MSG_MAX,
.cb = ctnl_cb,
};
static const struct nfnetlink_subsystem ctnl_exp_subsys = {
.name = "conntrack_expect",
.subsys_id = NFNL_SUBSYS_CTNETLINK_EXP,
.cb_count = IPCTNL_MSG_EXP_MAX,
.cb = ctnl_exp_cb,
};
MODULE_ALIAS("ip_conntrack_netlink");
MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
static int __net_init ctnetlink_net_init(struct net *net)
{
#ifdef CONFIG_NF_CONNTRACK_EVENTS
int ret;
ret = nf_conntrack_register_notifier(net, &ctnl_notifier);
if (ret < 0) {
pr_err("ctnetlink_init: cannot register notifier.\n");
goto err_out;
}
ret = nf_ct_expect_register_notifier(net, &ctnl_notifier_exp);
if (ret < 0) {
pr_err("ctnetlink_init: cannot expect register notifier.\n");
goto err_unreg_notifier;
}
#endif
return 0;
#ifdef CONFIG_NF_CONNTRACK_EVENTS
err_unreg_notifier:
nf_conntrack_unregister_notifier(net, &ctnl_notifier);
err_out:
return ret;
#endif
}
static void ctnetlink_net_exit(struct net *net)
{
#ifdef CONFIG_NF_CONNTRACK_EVENTS
nf_ct_expect_unregister_notifier(net, &ctnl_notifier_exp);
nf_conntrack_unregister_notifier(net, &ctnl_notifier);
#endif
}
static void __net_exit ctnetlink_net_exit_batch(struct list_head *net_exit_list)
{
struct net *net;
list_for_each_entry(net, net_exit_list, exit_list)
ctnetlink_net_exit(net);
}
static struct pernet_operations ctnetlink_net_ops = {
.init = ctnetlink_net_init,
.exit_batch = ctnetlink_net_exit_batch,
};
static int __init ctnetlink_init(void)
{
int ret;
pr_info("ctnetlink v%s: registering with nfnetlink.\n", version);
ret = nfnetlink_subsys_register(&ctnl_subsys);
if (ret < 0) {
pr_err("ctnetlink_init: cannot register with nfnetlink.\n");
goto err_out;
}
ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
if (ret < 0) {
pr_err("ctnetlink_init: cannot register exp with nfnetlink.\n");
goto err_unreg_subsys;
}
if (register_pernet_subsys(&ctnetlink_net_ops)) {
pr_err("ctnetlink_init: cannot register pernet operations\n");
goto err_unreg_exp_subsys;
}
return 0;
err_unreg_exp_subsys:
nfnetlink_subsys_unregister(&ctnl_exp_subsys);
err_unreg_subsys:
nfnetlink_subsys_unregister(&ctnl_subsys);
err_out:
return ret;
}
static void __exit ctnetlink_exit(void)
{
pr_info("ctnetlink: unregistering from nfnetlink.\n");
unregister_pernet_subsys(&ctnetlink_net_ops);
nfnetlink_subsys_unregister(&ctnl_exp_subsys);
nfnetlink_subsys_unregister(&ctnl_subsys);
}
module_init(ctnetlink_init);
module_exit(ctnetlink_exit);