diff options
Diffstat (limited to 'net/netfilter/nf_conntrack_netlink.c')
| -rw-r--r-- | net/netfilter/nf_conntrack_netlink.c | 1838 |
1 files changed, 1838 insertions, 0 deletions
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c new file mode 100644 index 0000000..8e9a303 --- /dev/null +++ b/net/netfilter/nf_conntrack_netlink.c @@ -0,0 +1,1838 @@ +/* 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/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/netlink.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> +#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_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 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, const struct nf_conn *ct) +{ + struct nf_conntrack_l4proto *l4proto; + struct nlattr *nest_proto; + int ret; + + l4proto = nf_ct_l4proto_find_get(nf_ct_l3num(ct), nf_ct_protonum(ct)); + if (!l4proto->to_nlattr) { + nf_ct_l4proto_put(l4proto); + 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); + + nf_ct_l4proto_put(l4proto); + + nla_nest_end(skb, nest_proto); + + return ret; + +nla_put_failure: + nf_ct_l4proto_put(l4proto); + 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; + + rcu_read_lock(); + 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: + rcu_read_unlock(); + return 0; + +nla_put_failure: + rcu_read_unlock(); + 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; +} + +#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_secmark(struct sk_buff *skb, const struct nf_conn *ct) +{ + NLA_PUT_BE32(skb, CTA_SECMARK, htonl(ct->secmark)); + return 0; + +nla_put_failure: + return -1; +} +#else +#define ctnetlink_dump_secmark(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; +} + +#define tuple(ct, dir) (&(ct)->tuplehash[dir].tuple) + +static int +ctnetlink_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 nlattr *nest_parms; + unsigned char *b = skb_tail_pointer(skb); + + 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 = 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, 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, tuple(ct, IP_CT_DIR_REPLY)) < 0) + goto nla_put_failure; + nla_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_secmark(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; + + nlh->nlmsg_len = skb_tail_pointer(skb) - b; + return skb->len; + +nlmsg_failure: +nla_put_failure: + nlmsg_trim(skb, b); + return -1; +} + +#ifdef CONFIG_NF_CONNTRACK_EVENTS +static int ctnetlink_conntrack_event(struct notifier_block *this, + unsigned long events, void *ptr) +{ + struct nlmsghdr *nlh; + struct nfgenmsg *nfmsg; + struct nlattr *nest_parms; + struct nf_conn *ct = (struct nf_conn *)ptr; + struct sk_buff *skb; + unsigned int type; + sk_buff_data_t 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 = 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, 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, tuple(ct, IP_CT_DIR_REPLY)) < 0) + goto nla_put_failure; + nla_nest_end(skb, nest_parms); + + if (ctnetlink_dump_id(skb, ct) < 0) + goto nla_put_failure; + + if (ctnetlink_dump_status(skb, ct) < 0) + goto nla_put_failure; + + 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 nla_put_failure; + } else { + if (ctnetlink_dump_timeout(skb, ct) < 0) + goto nla_put_failure; + + if (events & IPCT_PROTOINFO + && ctnetlink_dump_protoinfo(skb, ct) < 0) + goto nla_put_failure; + + if ((events & IPCT_HELPER || nfct_help(ct)) + && ctnetlink_dump_helpinfo(skb, ct) < 0) + goto nla_put_failure; + +#ifdef CONFIG_NF_CONNTRACK_SECMARK + if ((events & IPCT_SECMARK || ct->secmark) + && ctnetlink_dump_secmark(skb, ct) < 0) + goto nla_put_failure; +#endif + + if (events & IPCT_RELATED && + ctnetlink_dump_master(skb, ct) < 0) + goto nla_put_failure; + + if (events & IPCT_NATSEQADJ && + ctnetlink_dump_nat_seq_adj(skb, ct) < 0) + goto nla_put_failure; + } + +#ifdef CONFIG_NF_CONNTRACK_MARK + if ((events & IPCT_MARK || ct->mark) + && ctnetlink_dump_mark(skb, ct) < 0) + goto nla_put_failure; +#endif + + nlh->nlmsg_len = skb->tail - b; + nfnetlink_send(skb, 0, group, 0); + return NOTIFY_DONE; + +nlmsg_failure: +nla_put_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; +} + +static int +ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb) +{ + struct nf_conn *ct, *last; + struct nf_conntrack_tuple_hash *h; + struct hlist_node *n; + struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh); + u_int8_t l3proto = nfmsg->nfgen_family; + + rcu_read_lock(); + last = (struct nf_conn *)cb->args[1]; + for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++) { +restart: + hlist_for_each_entry_rcu(h, n, &init_net.ct.hash[cb->args[0]], + hnode) { + 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, + 1, ct) < 0) { + if (!atomic_inc_not_zero(&ct->ct_general.use)) + continue; + 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: + rcu_read_unlock(); + 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); + + l3proto = nf_ct_l3proto_find_get(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); + } + + nf_ct_l3proto_put(l3proto); + + 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]); + + l4proto = nf_ct_l4proto_find_get(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); + } + + nf_ct_l4proto_put(l4proto); + + return ret; +} + +static int +ctnetlink_parse_tuple(struct nlattr *cda[], struct nf_conntrack_tuple *tuple, + enum ctattr_tuple 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], NULL); + + 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 inline int +ctnetlink_parse_help(struct nlattr *attr, char **helper_name) +{ + struct nlattr *tb[CTA_HELP_MAX+1]; + + nla_parse_nested(tb, CTA_HELP_MAX, attr, NULL); + + 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_STATUS] = { .type = NLA_U32 }, + [CTA_TIMEOUT] = { .type = NLA_U32 }, + [CTA_MARK] = { .type = NLA_U32 }, + [CTA_USE] = { .type = NLA_U32 }, + [CTA_ID] = { .type = NLA_U32 }, +}; + +static int +ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb, + struct nlmsghdr *nlh, struct nlattr *cda[]) +{ + 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 (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(&init_net); + return 0; + } + + if (err < 0) + return err; + + h = nf_conntrack_find_get(&init_net, &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; + } + } + + nf_ct_kill(ct); + nf_ct_put(ct); + + return 0; +} + +static int +ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb, + struct nlmsghdr *nlh, struct nlattr *cda[]) +{ + 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) + return netlink_dump_start(ctnl, skb, nlh, ctnetlink_dump_table, + ctnetlink_done); + + 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(&init_net, &tuple); + 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; +} + +#ifdef CONFIG_NF_NAT_NEEDED +static int +ctnetlink_parse_nat_setup(struct nf_conn *ct, + enum nf_nat_manip_type manip, + 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, struct nlattr *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, struct nlattr *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, struct nlattr *cda[]) +{ + struct nf_conntrack_helper *helper; + struct nf_conn_help *help = nfct_help(ct); + char *helpname; + 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_byname(helpname); + if (helper == NULL) + 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 { + help = nf_ct_helper_ext_add(ct, GFP_ATOMIC); + if (help == NULL) + return -ENOMEM; + } + + rcu_assign_pointer(help->helper, helper); + + return 0; +} + +static inline int +ctnetlink_change_timeout(struct nf_conn *ct, struct nlattr *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 inline int +ctnetlink_change_protoinfo(struct nf_conn *ct, struct nlattr *cda[]) +{ + struct nlattr *tb[CTA_PROTOINFO_MAX+1], *attr = cda[CTA_PROTOINFO]; + struct nf_conntrack_l4proto *l4proto; + int err = 0; + + nla_parse_nested(tb, CTA_PROTOINFO_MAX, attr, NULL); + + l4proto = nf_ct_l4proto_find_get(nf_ct_l3num(ct), nf_ct_protonum(ct)); + if (l4proto->from_nlattr) + err = l4proto->from_nlattr(tb, ct); + nf_ct_l4proto_put(l4proto); + + return err; +} + +#ifdef CONFIG_NF_NAT_NEEDED +static inline int +change_nat_seq_adj(struct nf_nat_seq *natseq, struct nlattr *attr) +{ + struct nlattr *cda[CTA_NAT_SEQ_MAX+1]; + + nla_parse_nested(cda, CTA_NAT_SEQ_MAX, attr, NULL); + + 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, struct nlattr *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, struct nlattr *cda[]) +{ + int err; + + 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 int +ctnetlink_create_conntrack(struct nlattr *cda[], + struct nf_conntrack_tuple *otuple, + struct nf_conntrack_tuple *rtuple, + struct nf_conn *master_ct) +{ + struct nf_conn *ct; + int err = -EINVAL; + struct nf_conn_help *help; + struct nf_conntrack_helper *helper; + + ct = nf_conntrack_alloc(&init_net, otuple, rtuple, GFP_ATOMIC); + if (ct == NULL || IS_ERR(ct)) + return -ENOMEM; + + if (!cda[CTA_TIMEOUT]) + goto err; + ct->timeout.expires = ntohl(nla_get_be32(cda[CTA_TIMEOUT])); + + ct->timeout.expires = jiffies + ct->timeout.expires * HZ; + ct->status |= IPS_CONFIRMED; + + rcu_read_lock(); + helper = __nf_ct_helper_find(rtuple); + if (helper) { + help = nf_ct_helper_ext_add(ct, GFP_ATOMIC); + if (help == NULL) { + rcu_read_unlock(); + err = -ENOMEM; + goto err; + } + /* not in hash table yet so not strictly necessary */ + rcu_assign_pointer(help->helper, helper); + } + + if (cda[CTA_STATUS]) { + err = ctnetlink_change_status(ct, cda); + if (err < 0) { + rcu_read_unlock(); + goto err; + } + } + + if (cda[CTA_NAT_SRC] || cda[CTA_NAT_DST]) { + err = ctnetlink_change_nat(ct, cda); + if (err < 0) { + rcu_read_unlock(); + goto err; + } + } + + if (cda[CTA_PROTOINFO]) { + err = ctnetlink_change_protoinfo(ct, cda); + if (err < 0) { + rcu_read_unlock(); + goto err; + } + } + + nf_ct_acct_ext_add(ct, GFP_ATOMIC); + +#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 (master_ct) { + __set_bit(IPS_EXPECTED_BIT, &ct->status); + ct->master = master_ct; + } + + add_timer(&ct->timeout); + nf_conntrack_hash_insert(ct); + rcu_read_unlock(); + + return 0; + +err: + nf_conntrack_free(ct); + return err; +} + +static int +ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb, + struct nlmsghdr *nlh, struct nlattr *cda[]) +{ + 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 (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(&init_net, &otuple); + else if (cda[CTA_TUPLE_REPLY]) + h = __nf_conntrack_find(&init_net, &rtuple); + + if (h == NULL) { + struct nf_conntrack_tuple master; + struct nf_conntrack_tuple_hash *master_h = NULL; + struct nf_conn *master_ct = NULL; + + if (cda[CTA_TUPLE_MASTER]) { + err = ctnetlink_parse_tuple(cda, + &master, + CTA_TUPLE_MASTER, + u3); + if (err < 0) + goto out_unlock; + + master_h = __nf_conntrack_find(&init_net, &master); + if (master_h == NULL) { + err = -ENOENT; + goto out_unlock; + } + master_ct = nf_ct_tuplehash_to_ctrack(master_h); + atomic_inc(&master_ct->ct_general.use); + } + + err = -ENOENT; + if (nlh->nlmsg_flags & NLM_F_CREATE) + err = ctnetlink_create_conntrack(cda, + &otuple, + &rtuple, + master_ct); + spin_unlock_bh(&nf_conntrack_lock); + + if (err < 0 && master_ct) + nf_ct_put(master_ct); + + 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)) { + /* we only allow nat config for new conntracks */ + if (cda[CTA_NAT_SRC] || cda[CTA_NAT_DST]) { + err = -EOPNOTSUPP; + goto out_unlock; + } + /* can't link an existing conntrack to a master */ + if (cda[CTA_TUPLE_MASTER]) { + err = -EOPNOTSUPP; + goto out_unlock; + } + err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h), + cda); + } + +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)); + m.src.u.all = mask->src.u.all; + memcpy(&m.src.u3, &mask->src.u3, sizeof(m.src.u3)); + + nest_parms = nla_nest_start(skb, CTA_EXPECT_MASK | NLA_F_NESTED); + if (!nest_parms) + goto nla_put_failure; + + l3proto = nf_ct_l3proto_find_get(tuple->src.l3num); + ret = ctnetlink_dump_tuples_ip(skb, &m, l3proto); + nf_ct_l3proto_put(l3proto); + + if (unlikely(ret < 0)) + goto nla_put_failure; + + l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum); + ret = ctnetlink_dump_tuples_proto(skb, &m, l4proto); + nf_ct_l4proto_put(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; + + 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)); + + return 0; + +nla_put_failure: + return -1; +} + +static int +ctnetlink_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 = skb_tail_pointer(skb); + + 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 nla_put_failure; + + nlh->nlmsg_len = skb_tail_pointer(skb) - b; + return skb->len; + +nlmsg_failure: +nla_put_failure: + nlmsg_trim(skb, b); + return -1; +} + +#ifdef CONFIG_NF_CONNTRACK_EVENTS +static 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; + sk_buff_data_t 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 nla_put_failure; + + nlh->nlmsg_len = skb->tail - b; + nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0); + return NOTIFY_DONE; + +nlmsg_failure: +nla_put_failure: + kfree_skb(skb); + return NOTIFY_DONE; +} +#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 = &init_net; + 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, + 1, 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_TIMEOUT] = { .type = NLA_U32 }, + [CTA_EXPECT_ID] = { .type = NLA_U32 }, +}; + +static int +ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb, + struct nlmsghdr *nlh, struct nlattr *cda[]) +{ + 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 (nlh->nlmsg_flags & NLM_F_DUMP) { + return netlink_dump_start(ctnl, skb, nlh, + ctnetlink_exp_dump_table, + ctnetlink_exp_done); + } + + 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(&init_net, &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 = 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_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, + struct nlmsghdr *nlh, struct nlattr *cda[]) +{ + struct nf_conntrack_expect *exp; + struct nf_conntrack_tuple tuple; + struct nf_conntrack_helper *h; + struct nfgenmsg *nfmsg = NLMSG_DATA(nlh); + struct hlist_node *n, *next; + u_int8_t u3 = nfmsg->nfgen_family; + unsigned int i; + int err; + + if (cda[CTA_EXPECT_TUPLE]) { + /* 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_ct_expect_find_get(&init_net, &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 */ + nf_ct_unexpect_related(exp); + /* 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); + h = __nf_conntrack_helper_find_byname(name); + if (!h) { + spin_unlock_bh(&nf_conntrack_lock); + return -EOPNOTSUPP; + } + for (i = 0; i < nf_ct_expect_hsize; i++) { + hlist_for_each_entry_safe(exp, n, next, + &init_net.ct.expect_hash[i], + hnode) { + m_help = nfct_help(exp->master); + if (m_help->helper == h + && del_timer(&exp->timeout)) { + nf_ct_unlink_expect(exp); + 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, + &init_net.ct.expect_hash[i], + hnode) { + if (del_timer(&exp->timeout)) { + nf_ct_unlink_expect(exp); + nf_ct_expect_put(exp); + } + } + } + spin_unlock_bh(&nf_conntrack_lock); + } + + return 0; +} +static int +ctnetlink_change_expect(struct nf_conntrack_expect *x, struct nlattr *cda[]) +{ + return -EOPNOTSUPP; +} + +static int +ctnetlink_create_expect(struct nlattr *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(&init_net, &master_tuple); + 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_ct_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.src.u3, &mask.src.u3, sizeof(exp->mask.src.u3)); + exp->mask.src.u.all = mask.src.u.all; + + err = nf_ct_expect_related(exp); + 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, + struct nlmsghdr *nlh, struct nlattr *cda[]) +{ + 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 (!cda[CTA_EXPECT_TUPLE] + || !cda[CTA_EXPECT_MASK] + || !cda[CTA_EXPECT_MASTER]) + return -EINVAL; + + 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(&init_net, &tuple); + + if (!exp) { + spin_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); + spin_unlock_bh(&nf_conntrack_lock); + + return err; +} + +#ifdef CONFIG_NF_CONNTRACK_EVENTS +static struct notifier_block ctnl_notifier = { + .notifier_call = ctnetlink_conntrack_event, +}; + +static struct notifier_block ctnl_notifier_exp = { + .notifier_call = 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; + + 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_ct_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_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) +{ + printk("ctnetlink: unregistering from nfnetlink.\n"); + +#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); + return; +} + +module_init(ctnetlink_init); +module_exit(ctnetlink_exit); |
