- 根目录:
- net
- netfilter
- nf_conntrack_netlink.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) 2005-2008 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
ctnetlink_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 nlattr *nest_count;
const struct nf_conn_counter *acct;
acct = nf_conn_acct_find(ct);
if (!acct)
return 0;
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(acct[dir].packets));
NLA_PUT_BE64(skb, CTA_COUNTERS_BYTES,
cpu_to_be64(acct[dir].bytes));
nla_nest_end(skb, nest_count);
return 0;
nla_put_failure:
return -1;
}
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,
int event, struct nf_conn *ct)
{
struct nlmsghdr *nlh;
struct nfgenmsg *nfmsg;
struct nlattr *nest_parms;
unsigned int flags = pid ? NLM_F_MULTI : 0;
event |= NFNL_SUBSYS_CTNETLINK << 8;
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) < 0 ||
ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 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) < 0 ||
ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 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,
IPCTNL_MSG_CT_NEW, ct) < 0) {
nf_conntrack_get(&ct->ct_general);
cb->args[1] = (unsigned long)ct;
goto out;
}
if (NFNL_MSG_TYPE(cb->nlh->nlmsg_type) ==
IPCTNL_MSG_CT_GET_CTRZERO) {
struct nf_conn_counter *acct;
acct = nf_conn_acct_find(ct);
if (acct)
memset(acct, 0, sizeof(struct nf_conn_counter[IP_CT_DIR_MAX]));
}
}
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,
IPCTNL_MSG_CT_NEW, 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,
IP_NAT_MANIP_DST,
cda[CTA_NAT_DST]);
if (ret < 0)
return ret;
}
if (cda[CTA_NAT_SRC]) {
ret = ctnetlink_parse_nat_setup(ct,
IP_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_assign_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_assign_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_assign_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_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) {
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 __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;
}
#ifdef CONFIG_NF_CONNTRACK_EVENTS
ret = nf_conntrack_register_notifier(&ctnl_notifier);
if (ret < 0) {
pr_err("ctnetlink_init: cannot register notifier.\n");
goto err_unreg_exp_subsys;
}
ret = nf_ct_expect_register_notifier(&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(&ctnl_notifier);
err_unreg_exp_subsys:
nfnetlink_subsys_unregister(&ctnl_exp_subsys);
#endif
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");
nf_ct_remove_userspace_expectations();
#ifdef CONFIG_NF_CONNTRACK_EVENTS
nf_ct_expect_unregister_notifier(&ctnl_notifier_exp);
nf_conntrack_unregister_notifier(&ctnl_notifier);
#endif
nfnetlink_subsys_unregister(&ctnl_exp_subsys);
nfnetlink_subsys_unregister(&ctnl_subsys);
}
module_init(ctnetlink_init);
module_exit(ctnetlink_exit);