/* 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) 2005-2006 by Pablo Neira Ayuso <pablo@eurodev.net> * * I‘ve reworked this stuff to use attributes instead of conntrack * structures. 5.44 am. I need more tea. --pablo 05/07/11. * * 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. * * Derived from ip_conntrack_netlink.c: Port by Pablo Neira Ayuso (05/11/14) */#include <linux/init.h>#include <linux/module.h>#include <linux/kernel.h>#include <linux/types.h>#include <linux/timer.h>#include <linux/skbuff.h>#include <linux/errno.h>#include <linux/netlink.h>#include <linux/spinlock.h>#include <linux/interrupt.h>#include <linux/notifier.h>#include <linux/netfilter.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>#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 intctnetlink_dump_tuples_proto(struct sk_buff *skb,			    const struct nf_conntrack_tuple *tuple,			    struct nf_conntrack_l4proto *l4proto){	int ret = 0;	struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_PROTO);	NFA_PUT(skb, CTA_PROTO_NUM, sizeof(u_int8_t), &tuple->dst.protonum);	if (likely(l4proto->tuple_to_nfattr))		ret = l4proto->tuple_to_nfattr(skb, tuple);	NFA_NEST_END(skb, nest_parms);	return ret;nfattr_failure:	return -1;}static inline intctnetlink_dump_tuples_ip(struct sk_buff *skb,			 const struct nf_conntrack_tuple *tuple,			 struct nf_conntrack_l3proto *l3proto){	int ret = 0;	struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_IP);	if (likely(l3proto->tuple_to_nfattr))		ret = l3proto->tuple_to_nfattr(skb, tuple);	NFA_NEST_END(skb, nest_parms);	return ret;nfattr_failure:	return -1;}static inline intctnetlink_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_get(tuple->src.l3num);	ret = ctnetlink_dump_tuples_ip(skb, tuple, l3proto);	nf_ct_l3proto_put(l3proto);	if (unlikely(ret < 0))		return ret;	l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);	ret = ctnetlink_dump_tuples_proto(skb, tuple, l4proto);	nf_ct_l4proto_put(l4proto);	return ret;}static inline intctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct){	__be32 status = htonl((u_int32_t) ct->status);	NFA_PUT(skb, CTA_STATUS, sizeof(status), &status);	return 0;nfattr_failure:	return -1;}static inline intctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct){	long timeout_l = ct->timeout.expires - jiffies;	__be32 timeout;	if (timeout_l < 0)		timeout = 0;	else		timeout = htonl(timeout_l / HZ);	NFA_PUT(skb, CTA_TIMEOUT, sizeof(timeout), &timeout);	return 0;nfattr_failure:	return -1;}static inline intctnetlink_dump_protoinfo(struct sk_buff *skb, const struct nf_conn *ct){	struct nf_conntrack_l4proto *l4proto = nf_ct_l4proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num, ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);	struct nfattr *nest_proto;	int ret;	if (!l4proto->to_nfattr) {		nf_ct_l4proto_put(l4proto);		return 0;	}	nest_proto = NFA_NEST(skb, CTA_PROTOINFO);	ret = l4proto->to_nfattr(skb, nest_proto, ct);	nf_ct_l4proto_put(l4proto);	NFA_NEST_END(skb, nest_proto);	return ret;nfattr_failure:	nf_ct_l4proto_put(l4proto);	return -1;}static inline intctnetlink_dump_helpinfo(struct sk_buff *skb, const struct nf_conn *ct){	struct nfattr *nest_helper;	const struct nf_conn_help *help = nfct_help(ct);	if (!help || !help->helper)		return 0;	nest_helper = NFA_NEST(skb, CTA_HELP);	NFA_PUT(skb, CTA_HELP_NAME, strlen(help->helper->name), help->helper->name);	if (help->helper->to_nfattr)		help->helper->to_nfattr(skb, ct);	NFA_NEST_END(skb, nest_helper);	return 0;nfattr_failure:	return -1;}#ifdef CONFIG_NF_CT_ACCTstatic inline intctnetlink_dump_counters(struct sk_buff *skb, const struct nf_conn *ct,			enum ip_conntrack_dir dir){	enum ctattr_type type = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;	struct nfattr *nest_count = NFA_NEST(skb, type);	__be32 tmp;	tmp = htonl(ct->counters[dir].packets);	NFA_PUT(skb, CTA_COUNTERS32_PACKETS, sizeof(u_int32_t), &tmp);	tmp = htonl(ct->counters[dir].bytes);	NFA_PUT(skb, CTA_COUNTERS32_BYTES, sizeof(u_int32_t), &tmp);	NFA_NEST_END(skb, nest_count);	return 0;nfattr_failure:	return -1;}#else#define ctnetlink_dump_counters(a, b, c) (0)#endif#ifdef CONFIG_NF_CONNTRACK_MARKstatic inline intctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct){	__be32 mark = htonl(ct->mark);	NFA_PUT(skb, CTA_MARK, sizeof(u_int32_t), &mark);	return 0;nfattr_failure:	return -1;}#else#define ctnetlink_dump_mark(a, b) (0)#endifstatic inline intctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct){	__be32 id = htonl(ct->id);	NFA_PUT(skb, CTA_ID, sizeof(u_int32_t), &id);	return 0;nfattr_failure:	return -1;}static inline intctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct){	__be32 use = htonl(atomic_read(&ct->ct_general.use));	NFA_PUT(skb, CTA_USE, sizeof(u_int32_t), &use);	return 0;nfattr_failure:	return -1;}#define tuple(ct, dir) (&(ct)->tuplehash[dir].tuple)static intctnetlink_fill_info(struct sk_buff *skb, u32 pid, u32 seq,		    int event, int nowait,		    const struct nf_conn *ct){	struct nlmsghdr *nlh;	struct nfgenmsg *nfmsg;	struct nfattr *nest_parms;	unsigned char *b;	b = skb->tail;	event |= NFNL_SUBSYS_CTNETLINK << 8;	nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));	nfmsg  = NLMSG_DATA(nlh);	nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;	nfmsg->nfgen_family =		ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;	nfmsg->version      = NFNETLINK_V0;	nfmsg->res_id	    = 0;	nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);	if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)		goto nfattr_failure;	NFA_NEST_END(skb, nest_parms);	nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);	if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)		goto nfattr_failure;	NFA_NEST_END(skb, nest_parms);	if (ctnetlink_dump_status(skb, ct) < 0 ||	    ctnetlink_dump_timeout(skb, ct) < 0 ||	    ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||	    ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0 ||	    ctnetlink_dump_protoinfo(skb, ct) < 0 ||	    ctnetlink_dump_helpinfo(skb, ct) < 0 ||	    ctnetlink_dump_mark(skb, ct) < 0 ||	    ctnetlink_dump_id(skb, ct) < 0 ||	    ctnetlink_dump_use(skb, ct) < 0)		goto nfattr_failure;	nlh->nlmsg_len = skb->tail - b;	return skb->len;nlmsg_failure:nfattr_failure:	skb_trim(skb, b - skb->data);	return -1;}#ifdef CONFIG_NF_CONNTRACK_EVENTSstatic int ctnetlink_conntrack_event(struct notifier_block *this,				     unsigned long events, void *ptr){	struct nlmsghdr *nlh;	struct nfgenmsg *nfmsg;	struct nfattr *nest_parms;	struct nf_conn *ct = (struct nf_conn *)ptr;	struct sk_buff *skb;	unsigned int type;	unsigned char *b;	unsigned int flags = 0, group;	/* ignore our fake conntrack entry */	if (ct == &nf_conntrack_untracked)		return NOTIFY_DONE;	if (events & IPCT_DESTROY) {		type = IPCTNL_MSG_CT_DELETE;		group = NFNLGRP_CONNTRACK_DESTROY;	} else  if (events & (IPCT_NEW | IPCT_RELATED)) {		type = IPCTNL_MSG_CT_NEW;		flags = NLM_F_CREATE|NLM_F_EXCL;		group = NFNLGRP_CONNTRACK_NEW;	} else  if (events & (IPCT_STATUS | IPCT_PROTOINFO)) {		type = IPCTNL_MSG_CT_NEW;		group = NFNLGRP_CONNTRACK_UPDATE;	} else		return NOTIFY_DONE;	if (!nfnetlink_has_listeners(group))		return NOTIFY_DONE;	skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);	if (!skb)		return NOTIFY_DONE;	b = skb->tail;	type |= NFNL_SUBSYS_CTNETLINK << 8;	nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));	nfmsg = NLMSG_DATA(nlh);	nlh->nlmsg_flags    = flags;	nfmsg->nfgen_family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;	nfmsg->version	= NFNETLINK_V0;	nfmsg->res_id	= 0;	nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);	if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)		goto nfattr_failure;	NFA_NEST_END(skb, nest_parms);	nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);	if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)		goto nfattr_failure;	NFA_NEST_END(skb, nest_parms);	if (events & IPCT_DESTROY) {		if (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||		    ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0)			goto nfattr_failure;	} else {		if (ctnetlink_dump_status(skb, ct) < 0)			goto nfattr_failure;		if (ctnetlink_dump_timeout(skb, ct) < 0)			goto nfattr_failure;		if (events & IPCT_PROTOINFO		    && ctnetlink_dump_protoinfo(skb, ct) < 0)			goto nfattr_failure;		if ((events & IPCT_HELPER || nfct_help(ct))		    && ctnetlink_dump_helpinfo(skb, ct) < 0)			goto nfattr_failure;#ifdef CONFIG_NF_CONNTRACK_MARK		if ((events & IPCT_MARK || ct->mark)		    && ctnetlink_dump_mark(skb, ct) < 0)			goto nfattr_failure;#endif		if (events & IPCT_COUNTER_FILLING &&		    (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||		     ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0))			goto nfattr_failure;	}	nlh->nlmsg_len = skb->tail - b;	nfnetlink_send(skb, 0, group, 0);	return NOTIFY_DONE;nlmsg_failure:nfattr_failure:	kfree_skb(skb);	return NOTIFY_DONE;}#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;}#define L3PROTO(ct) ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3numstatic intctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb){	struct nf_conn *ct, *last;	struct nf_conntrack_tuple_hash *h;	struct list_head *i;	struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);	u_int8_t l3proto = nfmsg->nfgen_family;	read_lock_bh(&nf_conntrack_lock);	last = (struct nf_conn *)cb->args[1];	for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++) {restart:		list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {			h = (struct nf_conntrack_tuple_hash *) i;			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 && L3PROTO(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,						IPCTNL_MSG_CT_NEW,						1, ct) < 0) {				nf_conntrack_get(&ct->ct_general);				cb->args[1] = (unsigned long)ct;				goto out;			}#ifdef CONFIG_NF_CT_ACCT			if (NFNL_MSG_TYPE(cb->nlh->nlmsg_type) ==						IPCTNL_MSG_CT_GET_CTRZERO)				memset(&ct->counters, 0, sizeof(ct->counters));#endif		}		if (cb->args[1]) {			cb->args[1] = 0;			goto restart;		}	}out:	read_unlock_bh(&nf_conntrack_lock);	if (last)		nf_ct_put(last);	return skb->len;}static inline intctnetlink_parse_tuple_ip(struct nfattr *attr, struct nf_conntrack_tuple *tuple){	struct nfattr *tb[CTA_IP_MAX];	struct nf_conntrack_l3proto *l3proto;	int ret = 0;	nfattr_parse_nested(tb, CTA_IP_MAX, attr);	l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);	if (likely(l3proto->nfattr_to_tuple))		ret = l3proto->nfattr_to_tuple(tb, tuple);	nf_ct_l3proto_put(l3proto);	return ret;}static const size_t cta_min_proto[CTA_PROTO_MAX] = {	[CTA_PROTO_NUM-1]	= sizeof(u_int8_t),};static inline intctnetlink_parse_tuple_proto(struct nfattr *attr,			    struct nf_conntrack_tuple *tuple){	struct nfattr *tb[CTA_PROTO_MAX];	struct nf_conntrack_l4proto *l4proto;	int ret = 0;	nfattr_parse_nested(tb, CTA_PROTO_MAX, attr);	if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto))		return -EINVAL;	if (!tb[CTA_PROTO_NUM-1])		return -EINVAL;	tuple->dst.protonum = *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_NUM-1]);	l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);	if (likely(l4proto->nfattr_to_tuple))		ret = l4proto->nfattr_to_tuple(tb, tuple);	nf_ct_l4proto_put(l4proto);	return ret;}static inline intctnetlink_parse_tuple(struct nfattr *cda[], struct nf_conntrack_tuple *tuple,		      enum ctattr_tuple type, u_int8_t l3num){	struct nfattr *tb[CTA_TUPLE_MAX];	int err;	memset(tuple, 0, sizeof(*tuple));	nfattr_parse_nested(tb, CTA_TUPLE_MAX, cda[type-1]);	if (!tb[CTA_TUPLE_IP-1])		return -EINVAL;	tuple->src.l3num = l3num;	err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP-1], tuple);	if (err < 0)		return err;	if (!tb[CTA_TUPLE_PROTO-1])		return -EINVAL;	err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO-1], 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;}#ifdef CONFIG_NF_NAT_NEEDEDstatic const size_t cta_min_protonat[CTA_PROTONAT_MAX] = {	[CTA_PROTONAT_PORT_MIN-1]       = sizeof(u_int16_t),	[CTA_PROTONAT_PORT_MAX-1]       = sizeof(u_int16_t),};static int nfnetlink_parse_nat_proto(struct nfattr *attr,				     const struct nf_conn *ct,				     struct nf_nat_range *range){	struct nfattr *tb[CTA_PROTONAT_MAX];	struct nf_nat_protocol *npt;	nfattr_parse_nested(tb, CTA_PROTONAT_MAX, attr);	if (nfattr_bad_size(tb, CTA_PROTONAT_MAX, cta_min_protonat))		return -EINVAL;	npt = nf_nat_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);	if (!npt->nfattr_to_range) {		nf_nat_proto_put(npt);		return 0;	}	/* nfattr_to_range returns 1 if it parsed, 0 if not, neg. on error */	if (npt->nfattr_to_range(tb, range) > 0)		range->flags |= IP_NAT_RANGE_PROTO_SPECIFIED;	nf_nat_proto_put(npt);	return 0;}static const size_t cta_min_nat[CTA_NAT_MAX] = {	[CTA_NAT_MINIP-1]       = sizeof(u_int32_t),	[CTA_NAT_MAXIP-1]       = sizeof(u_int32_t),};static inline intnfnetlink_parse_nat(struct nfattr *nat,		    const struct nf_conn *ct, struct nf_nat_range *range){	struct nfattr *tb[CTA_NAT_MAX];	int err;	memset(range, 0, sizeof(*range));	nfattr_parse_nested(tb, CTA_NAT_MAX, nat);	if (nfattr_bad_size(tb, CTA_NAT_MAX, cta_min_nat))		return -EINVAL;	if (tb[CTA_NAT_MINIP-1])		range->min_ip = *(__be32 *)NFA_DATA(tb[CTA_NAT_MINIP-1]);	if (!tb[CTA_NAT_MAXIP-1])		range->max_ip = range->min_ip;	else		range->max_ip = *(__be32 *)NFA_DATA(tb[CTA_NAT_MAXIP-1]);	if (range->min_ip)		range->flags |= IP_NAT_RANGE_MAP_IPS;	if (!tb[CTA_NAT_PROTO-1])		return 0;	err = nfnetlink_parse_nat_proto(tb[CTA_NAT_PROTO-1], ct, range);	if (err < 0)		return err;	return 0;}#endifstatic inline intctnetlink_parse_help(struct nfattr *attr, char **helper_name){	struct nfattr *tb[CTA_HELP_MAX];	nfattr_parse_nested(tb, CTA_HELP_MAX, attr);	if (!tb[CTA_HELP_NAME-1])		return -EINVAL;	*helper_name = NFA_DATA(tb[CTA_HELP_NAME-1]);	return 0;}static const size_t cta_min[CTA_MAX] = {	[CTA_STATUS-1] 		= sizeof(u_int32_t),	[CTA_TIMEOUT-1] 	= sizeof(u_int32_t),	[CTA_MARK-1]		= sizeof(u_int32_t),	[CTA_USE-1]		= sizeof(u_int32_t),	[CTA_ID-1]		= sizeof(u_int32_t)};static intctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,			struct nlmsghdr *nlh, struct nfattr *cda[], int *errp){	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;	int err = 0;	if (nfattr_bad_size(cda, CTA_MAX, cta_min))		return -EINVAL;	if (cda[CTA_TUPLE_ORIG-1])		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);	else if (cda[CTA_TUPLE_REPLY-1])		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);	else {		/* Flush the whole table */		nf_conntrack_flush();		return 0;	}	if (err < 0)		return err;	h = nf_conntrack_find_get(&tuple, NULL);	if (!h)		return -ENOENT;	ct = nf_ct_tuplehash_to_ctrack(h);	if (cda[CTA_ID-1]) {		u_int32_t id = ntohl(*(__be32 *)NFA_DATA(cda[CTA_ID-1]));		if (ct->id != id) {			nf_ct_put(ct);			return -ENOENT;		}	}	if (del_timer(&ct->timeout))		ct->timeout.function((unsigned long)ct);	nf_ct_put(ct);	return 0;}static intctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,			struct nlmsghdr *nlh, struct nfattr *cda[], int *errp){	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;	int err = 0;	if (nlh->nlmsg_flags & NLM_F_DUMP) {		u32 rlen;#ifndef CONFIG_NF_CT_ACCT		if (NFNL_MSG_TYPE(nlh->nlmsg_type) == IPCTNL_MSG_CT_GET_CTRZERO)			return -ENOTSUPP;#endif		if ((*errp = netlink_dump_start(ctnl, skb, nlh,						ctnetlink_dump_table,						ctnetlink_done)) != 0)			return -EINVAL;		rlen = NLMSG_ALIGN(nlh->nlmsg_len);		if (rlen > skb->len)			rlen = skb->len;		skb_pull(skb, rlen);		return 0;	}	if (nfattr_bad_size(cda, CTA_MAX, cta_min))		return -EINVAL;	if (cda[CTA_TUPLE_ORIG-1])		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);	else if (cda[CTA_TUPLE_REPLY-1])		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);	else		return -EINVAL;	if (err < 0)		return err;	h = nf_conntrack_find_get(&tuple, NULL);	if (!h)		return -ENOENT;	ct = nf_ct_tuplehash_to_ctrack(h);	err = -ENOMEM;	skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);	if (!skb2) {		nf_ct_put(ct);		return -ENOMEM;	}	err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,				  IPCTNL_MSG_CT_NEW, 1, ct);	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:	return err;}static inline intctnetlink_change_status(struct nf_conn *ct, struct nfattr *cda[]){	unsigned long d;	unsigned int status = ntohl(*(__be32 *)NFA_DATA(cda[CTA_STATUS-1]));	d = ct->status ^ status;	if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))		/* unchangeable */		return -EINVAL;	if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))		/* SEEN_REPLY bit can only be set */		return -EINVAL;	if (d & IPS_ASSURED && !(status & IPS_ASSURED))		/* ASSURED bit can only be set */		return -EINVAL;	if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {#ifndef CONFIG_NF_NAT_NEEDED		return -EINVAL;#else		struct nf_nat_range range;		if (cda[CTA_NAT_DST-1]) {			if (nfnetlink_parse_nat(cda[CTA_NAT_DST-1], ct,						&range) < 0)				return -EINVAL;			if (nf_nat_initialized(ct,					       HOOK2MANIP(NF_IP_PRE_ROUTING)))				return -EEXIST;			nf_nat_setup_info(ct, &range, NF_IP_PRE_ROUTING);		}		if (cda[CTA_NAT_SRC-1]) {			if (nfnetlink_parse_nat(cda[CTA_NAT_SRC-1], ct,						&range) < 0)				return -EINVAL;			if (nf_nat_initialized(ct,					       HOOK2MANIP(NF_IP_POST_ROUTING)))				return -EEXIST;			nf_nat_setup_info(ct, &range, NF_IP_POST_ROUTING);		}#endif	}	/* 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 inline intctnetlink_change_helper(struct nf_conn *ct, struct nfattr *cda[]){	struct nf_conntrack_helper *helper;	struct nf_conn_help *help = nfct_help(ct);	char *helpname;	int err;	if (!help) {		/* FIXME: we need to reallocate and rehash */		return -EBUSY;	}	/* don‘t change helper of sibling connections */	if (ct->master)		return -EINVAL;	err = ctnetlink_parse_help(cda[CTA_HELP-1], &helpname);	if (err < 0)		return err;	helper = __nf_conntrack_helper_find_byname(helpname);	if (!helper) {		if (!strcmp(helpname, ""))			helper = NULL;		else			return -EINVAL;	}	if (help->helper) {		if (!helper) {			/* we had a helper before ... */			nf_ct_remove_expectations(ct);			help->helper = NULL;		} else {			/* need to zero data of old helper */			memset(&help->help, 0, sizeof(help->help));		}	}	help->helper = helper;	return 0;}static inline intctnetlink_change_timeout(struct nf_conn *ct, struct nfattr *cda[]){	u_int32_t timeout = ntohl(*(__be32 *)NFA_DATA(cda[CTA_TIMEOUT-1]));	if (!del_timer(&ct->timeout))		return -ETIME;	ct->timeout.expires = jiffies + timeout * HZ;	add_timer(&ct->timeout);	return 0;}static inline intctnetlink_change_protoinfo(struct nf_conn *ct, struct nfattr *cda[]){	struct nfattr *tb[CTA_PROTOINFO_MAX], *attr = cda[CTA_PROTOINFO-1];	struct nf_conntrack_l4proto *l4proto;	u_int16_t npt = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;	u_int16_t l3num = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;	int err = 0;	nfattr_parse_nested(tb, CTA_PROTOINFO_MAX, attr);	l4proto = nf_ct_l4proto_find_get(l3num, npt);	if (l4proto->from_nfattr)		err = l4proto->from_nfattr(tb, ct);	nf_ct_l4proto_put(l4proto);	return err;}static intctnetlink_change_conntrack(struct nf_conn *ct, struct nfattr *cda[]){	int err;	if (cda[CTA_HELP-1]) {		err = ctnetlink_change_helper(ct, cda);		if (err < 0)			return err;	}	if (cda[CTA_TIMEOUT-1]) {		err = ctnetlink_change_timeout(ct, cda);		if (err < 0)			return err;	}	if (cda[CTA_STATUS-1]) {		err = ctnetlink_change_status(ct, cda);		if (err < 0)			return err;	}	if (cda[CTA_PROTOINFO-1]) {		err = ctnetlink_change_protoinfo(ct, cda);		if (err < 0)			return err;	}#if defined(CONFIG_NF_CONNTRACK_MARK)	if (cda[CTA_MARK-1])		ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1]));#endif	return 0;}static intctnetlink_create_conntrack(struct nfattr *cda[],			   struct nf_conntrack_tuple *otuple,			   struct nf_conntrack_tuple *rtuple){	struct nf_conn *ct;	int err = -EINVAL;	struct nf_conn_help *help;	ct = nf_conntrack_alloc(otuple, rtuple);	if (ct == NULL || IS_ERR(ct))		return -ENOMEM;	if (!cda[CTA_TIMEOUT-1])		goto err;	ct->timeout.expires = ntohl(*(__be32 *)NFA_DATA(cda[CTA_TIMEOUT-1]));	ct->timeout.expires = jiffies + ct->timeout.expires * HZ;	ct->status |= IPS_CONFIRMED;	if (cda[CTA_STATUS-1]) {		err = ctnetlink_change_status(ct, cda);		if (err < 0)			goto err;	}	if (cda[CTA_PROTOINFO-1]) {		err = ctnetlink_change_protoinfo(ct, cda);		if (err < 0)			goto err;	}#if defined(CONFIG_NF_CONNTRACK_MARK)	if (cda[CTA_MARK-1])		ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1]));#endif	help = nfct_help(ct);	if (help)		help->helper = nf_ct_helper_find_get(rtuple);	add_timer(&ct->timeout);	nf_conntrack_hash_insert(ct);	if (help && help->helper)		nf_ct_helper_put(help->helper);	return 0;err:	nf_conntrack_free(ct);	return err;}static intctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,			struct nlmsghdr *nlh, struct nfattr *cda[], int *errp){	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;	int err = 0;	if (nfattr_bad_size(cda, CTA_MAX, cta_min))		return -EINVAL;	if (cda[CTA_TUPLE_ORIG-1]) {		err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3);		if (err < 0)			return err;	}	if (cda[CTA_TUPLE_REPLY-1]) {		err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3);		if (err < 0)			return err;	}	write_lock_bh(&nf_conntrack_lock);	if (cda[CTA_TUPLE_ORIG-1])		h = __nf_conntrack_find(&otuple, NULL);	else if (cda[CTA_TUPLE_REPLY-1])		h = __nf_conntrack_find(&rtuple, NULL);	if (h == NULL) {		write_unlock_bh(&nf_conntrack_lock);		err = -ENOENT;		if (nlh->nlmsg_flags & NLM_F_CREATE)			err = ctnetlink_create_conntrack(cda, &otuple, &rtuple);		return err;	}	/* implicit ‘else‘ */	/* we only allow nat config for new conntracks */	if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {		err = -EINVAL;		goto out_unlock;	}	/* 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))		err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h), cda);out_unlock:	write_unlock_bh(&nf_conntrack_lock);	return err;}/*********************************************************************** * EXPECT ***********************************************************************/static inline intctnetlink_exp_dump_tuple(struct sk_buff *skb,			 const struct nf_conntrack_tuple *tuple,			 enum ctattr_expect type){	struct nfattr *nest_parms = NFA_NEST(skb, type);	if (ctnetlink_dump_tuples(skb, tuple) < 0)		goto nfattr_failure;	NFA_NEST_END(skb, nest_parms);	return 0;nfattr_failure:	return -1;}static inline intctnetlink_exp_dump_mask(struct sk_buff *skb,			const struct nf_conntrack_tuple *tuple,			const struct nf_conntrack_tuple *mask){	int ret;	struct nf_conntrack_l3proto *l3proto;	struct nf_conntrack_l4proto *l4proto;	struct nfattr *nest_parms = NFA_NEST(skb, CTA_EXPECT_MASK);	l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);	ret = ctnetlink_dump_tuples_ip(skb, mask, l3proto);	nf_ct_l3proto_put(l3proto);	if (unlikely(ret < 0))		goto nfattr_failure;	l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);	ret = ctnetlink_dump_tuples_proto(skb, mask, l4proto);	nf_ct_l4proto_put(l4proto);	if (unlikely(ret < 0))		goto nfattr_failure;	NFA_NEST_END(skb, nest_parms);	return 0;nfattr_failure:	return -1;}static inline intctnetlink_exp_dump_expect(struct sk_buff *skb,			  const struct nf_conntrack_expect *exp){	struct nf_conn *master = exp->master;	__be32 timeout = htonl((exp->timeout.expires - jiffies) / HZ);	__be32 id = htonl(exp->id);	if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)		goto nfattr_failure;	if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)		goto nfattr_failure;	if (ctnetlink_exp_dump_tuple(skb,				 &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,				 CTA_EXPECT_MASTER) < 0)		goto nfattr_failure;	NFA_PUT(skb, CTA_EXPECT_TIMEOUT, sizeof(timeout), &timeout);	NFA_PUT(skb, CTA_EXPECT_ID, sizeof(u_int32_t), &id);	return 0;nfattr_failure:	return -1;}static intctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,		    int event,		    int nowait,		    const struct nf_conntrack_expect *exp){	struct nlmsghdr *nlh;	struct nfgenmsg *nfmsg;	unsigned char *b;	b = skb->tail;	event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;	nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));	nfmsg  = NLMSG_DATA(nlh);	nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;	nfmsg->nfgen_family = exp->tuple.src.l3num;	nfmsg->version	    = NFNETLINK_V0;	nfmsg->res_id	    = 0;	if (ctnetlink_exp_dump_expect(skb, exp) < 0)		goto nfattr_failure;	nlh->nlmsg_len = skb->tail - b;	return skb->len;nlmsg_failure:nfattr_failure:	skb_trim(skb, b - skb->data);	return -1;}#ifdef CONFIG_NF_CONNTRACK_EVENTSstatic int ctnetlink_expect_event(struct notifier_block *this,				  unsigned long events, void *ptr){	struct nlmsghdr *nlh;	struct nfgenmsg *nfmsg;	struct nf_conntrack_expect *exp = (struct nf_conntrack_expect *)ptr;	struct sk_buff *skb;	unsigned int type;	unsigned char *b;	int flags = 0;	if (events & IPEXP_NEW) {		type = IPCTNL_MSG_EXP_NEW;		flags = NLM_F_CREATE|NLM_F_EXCL;	} else		return NOTIFY_DONE;	if (!nfnetlink_has_listeners(NFNLGRP_CONNTRACK_EXP_NEW))		return NOTIFY_DONE;	skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);	if (!skb)		return NOTIFY_DONE;	b = skb->tail;	type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;	nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));	nfmsg = NLMSG_DATA(nlh);	nlh->nlmsg_flags    = flags;	nfmsg->nfgen_family = exp->tuple.src.l3num;	nfmsg->version	    = NFNETLINK_V0;	nfmsg->res_id	    = 0;	if (ctnetlink_exp_dump_expect(skb, exp) < 0)		goto nfattr_failure;	nlh->nlmsg_len = skb->tail - b;	nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);	return NOTIFY_DONE;nlmsg_failure:nfattr_failure:	kfree_skb(skb);	return NOTIFY_DONE;}#endifstatic intctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb){	struct nf_conntrack_expect *exp = NULL;	struct list_head *i;	u_int32_t *id = (u_int32_t *) &cb->args[0];	struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);	u_int8_t l3proto = nfmsg->nfgen_family;	read_lock_bh(&nf_conntrack_lock);	list_for_each_prev(i, &nf_conntrack_expect_list) {		exp = (struct nf_conntrack_expect *) i;		if (l3proto && exp->tuple.src.l3num != l3proto)			continue;		if (exp->id <= *id)			continue;		if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,					    cb->nlh->nlmsg_seq,					    IPCTNL_MSG_EXP_NEW,					    1, exp) < 0)			goto out;		*id = exp->id;	}out:	read_unlock_bh(&nf_conntrack_lock);	return skb->len;}static const size_t cta_min_exp[CTA_EXPECT_MAX] = {	[CTA_EXPECT_TIMEOUT-1]          = sizeof(u_int32_t),	[CTA_EXPECT_ID-1]               = sizeof(u_int32_t)};static intctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,		     struct nlmsghdr *nlh, struct nfattr *cda[], int *errp){	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;	int err = 0;	if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))		return -EINVAL;	if (nlh->nlmsg_flags & NLM_F_DUMP) {		u32 rlen;		if ((*errp = netlink_dump_start(ctnl, skb, nlh,						ctnetlink_exp_dump_table,						ctnetlink_done)) != 0)			return -EINVAL;		rlen = NLMSG_ALIGN(nlh->nlmsg_len);		if (rlen > skb->len)			rlen = skb->len;		skb_pull(skb, rlen);		return 0;	}	if (cda[CTA_EXPECT_MASTER-1])		err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);	else		return -EINVAL;	if (err < 0)		return err;	exp = nf_conntrack_expect_find_get(&tuple);	if (!exp)		return -ENOENT;	if (cda[CTA_EXPECT_ID-1]) {		__be32 id = *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);		if (exp->id != ntohl(id)) {			nf_conntrack_expect_put(exp);			return -ENOENT;		}	}	err = -ENOMEM;	skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);	if (!skb2)		goto out;	err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,				      nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,				      1, exp);	if (err <= 0)		goto free;	nf_conntrack_expect_put(exp);	return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);free:	kfree_skb(skb2);out:	nf_conntrack_expect_put(exp);	return err;}static intctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,		     struct nlmsghdr *nlh, struct nfattr *cda[], int *errp){	struct nf_conntrack_expect *exp, *tmp;	struct nf_conntrack_tuple tuple;	struct nf_conntrack_helper *h;	struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);	u_int8_t u3 = nfmsg->nfgen_family;	int err;	if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))		return -EINVAL;	if (cda[CTA_EXPECT_TUPLE-1]) {		/* delete a single expect by tuple */		err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);		if (err < 0)			return err;		/* bump usage count to 2 */		exp = nf_conntrack_expect_find_get(&tuple);		if (!exp)			return -ENOENT;		if (cda[CTA_EXPECT_ID-1]) {			__be32 id = *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);			if (exp->id != ntohl(id)) {				nf_conntrack_expect_put(exp);				return -ENOENT;			}		}		/* after list removal, usage count == 1 */		nf_conntrack_unexpect_related(exp);		/* have to put what we ‘get‘ above.		 * after this line usage count == 0 */		nf_conntrack_expect_put(exp);	} else if (cda[CTA_EXPECT_HELP_NAME-1]) {		char *name = NFA_DATA(cda[CTA_EXPECT_HELP_NAME-1]);		/* delete all expectations for this helper */		write_lock_bh(&nf_conntrack_lock);		h = __nf_conntrack_helper_find_byname(name);		if (!h) {			write_unlock_bh(&nf_conntrack_lock);			return -EINVAL;		}		list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,					 list) {			struct nf_conn_help *m_help = nfct_help(exp->master);			if (m_help->helper == h			    && del_timer(&exp->timeout)) {				nf_ct_unlink_expect(exp);				nf_conntrack_expect_put(exp);			}		}		write_unlock_bh(&nf_conntrack_lock);	} else {		/* This basically means we have to flush everything*/		write_lock_bh(&nf_conntrack_lock);		list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,					 list) {			if (del_timer(&exp->timeout)) {				nf_ct_unlink_expect(exp);				nf_conntrack_expect_put(exp);			}		}		write_unlock_bh(&nf_conntrack_lock);	}	return 0;}static intctnetlink_change_expect(struct nf_conntrack_expect *x, struct nfattr *cda[]){	return -EOPNOTSUPP;}static intctnetlink_create_expect(struct nfattr *cda[], u_int8_t u3){	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(&master_tuple, NULL);	if (!h)		return -ENOENT;	ct = nf_ct_tuplehash_to_ctrack(h);	help = nfct_help(ct);	if (!help || !help->helper) {		/* such conntrack hasn‘t got any helper, abort */		err = -EINVAL;		goto out;	}	exp = nf_conntrack_expect_alloc(ct);	if (!exp) {		err = -ENOMEM;		goto out;	}	exp->expectfn = NULL;	exp->flags = 0;	exp->master = ct;	exp->helper = NULL;	memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));	memcpy(&exp->mask, &mask, sizeof(struct nf_conntrack_tuple));	err = nf_conntrack_expect_related(exp);	nf_conntrack_expect_put(exp);out:	nf_ct_put(nf_ct_tuplehash_to_ctrack(h));	return err;}static intctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,		     struct nlmsghdr *nlh, struct nfattr *cda[], int *errp){	struct nf_conntrack_tuple tuple;	struct nf_conntrack_expect *exp;	struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);	u_int8_t u3 = nfmsg->nfgen_family;	int err = 0;	if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))		return -EINVAL;	if (!cda[CTA_EXPECT_TUPLE-1]	    || !cda[CTA_EXPECT_MASK-1]	    || !cda[CTA_EXPECT_MASTER-1])		return -EINVAL;	err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);	if (err < 0)		return err;	write_lock_bh(&nf_conntrack_lock);	exp = __nf_conntrack_expect_find(&tuple);	if (!exp) {		write_unlock_bh(&nf_conntrack_lock);		err = -ENOENT;		if (nlh->nlmsg_flags & NLM_F_CREATE)			err = ctnetlink_create_expect(cda, u3);		return err;	}	err = -EEXIST;	if (!(nlh->nlmsg_flags & NLM_F_EXCL))		err = ctnetlink_change_expect(exp, cda);	write_unlock_bh(&nf_conntrack_lock);	return err;}#ifdef CONFIG_NF_CONNTRACK_EVENTSstatic struct notifier_block ctnl_notifier = {	.notifier_call	= ctnetlink_conntrack_event,};static struct notifier_block ctnl_notifier_exp = {	.notifier_call	= ctnetlink_expect_event,};#endifstatic struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {	[IPCTNL_MSG_CT_NEW]		= { .call = ctnetlink_new_conntrack,					    .attr_count = CTA_MAX, },	[IPCTNL_MSG_CT_GET] 		= { .call = ctnetlink_get_conntrack,					    .attr_count = CTA_MAX, },	[IPCTNL_MSG_CT_DELETE]  	= { .call = ctnetlink_del_conntrack,					    .attr_count = CTA_MAX, },	[IPCTNL_MSG_CT_GET_CTRZERO] 	= { .call = ctnetlink_get_conntrack,					    .attr_count = CTA_MAX, },};static struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {	[IPCTNL_MSG_EXP_GET]		= { .call = ctnetlink_get_expect,					    .attr_count = CTA_EXPECT_MAX, },	[IPCTNL_MSG_EXP_NEW]		= { .call = ctnetlink_new_expect,					    .attr_count = CTA_EXPECT_MAX, },	[IPCTNL_MSG_EXP_DELETE]		= { .call = ctnetlink_del_expect,					    .attr_count = CTA_EXPECT_MAX, },};static struct nfnetlink_subsystem ctnl_subsys = {	.name				= "conntrack",	.subsys_id			= NFNL_SUBSYS_CTNETLINK,	.cb_count			= IPCTNL_MSG_MAX,	.cb				= ctnl_cb,};static 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 __init ctnetlink_init(void){	int ret;	printk("ctnetlink v%s: registering with nfnetlink.\n", version);	ret = nfnetlink_subsys_register(&ctnl_subsys);	if (ret < 0) {		printk("ctnetlink_init: cannot register with nfnetlink.\n");		goto err_out;	}	ret = nfnetlink_subsys_register(&ctnl_exp_subsys);	if (ret < 0) {		printk("ctnetlink_init: cannot register exp with nfnetlink.\n");		goto err_unreg_subsys;	}#ifdef CONFIG_NF_CONNTRACK_EVENTS	ret = nf_conntrack_register_notifier(&ctnl_notifier);	if (ret < 0) {		printk("ctnetlink_init: cannot register notifier.\n");		goto err_unreg_exp_subsys;	}	ret = nf_conntrack_expect_register_notifier(&ctnl_notifier_exp);	if (ret < 0) {		printk("ctnetlink_init: cannot expect register notifier.\n");		goto err_unreg_notifier;	}#endif	return 0;#ifdef CONFIG_NF_CONNTRACK_EVENTSerr_unreg_notifier:	nf_conntrack_unregister_notifier(&ctnl_notifier);err_unreg_exp_subsys:	nfnetlink_subsys_unregister(&ctnl_exp_subsys);#endiferr_unreg_subsys:	nfnetlink_subsys_unregister(&ctnl_subsys);err_out:	return ret;}static void __exit ctnetlink_exit(void){	printk("ctnetlink: unregistering from nfnetlink.\n");#ifdef CONFIG_NF_CONNTRACK_EVENTS	nf_conntrack_expect_unregister_notifier(&ctnl_notifier_exp);	nf_conntrack_unregister_notifier(&ctnl_notifier);#endif	nfnetlink_subsys_unregister(&ctnl_exp_subsys);	nfnetlink_subsys_unregister(&ctnl_subsys);	return;}module_init(ctnetlink_init);module_exit(ctnetlink_exit);