| /* 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 by Pablo Neira Ayuso <pablo@eurodev.net> |
| * |
| * I've reworked this stuff to use attributes instead of conntrack |
| * structures. 5.44 am. I need more tea. --pablo 05/07/11. |
| * |
| * Initial connection tracking via netlink development funded and |
| * generally made possible by Network Robots, Inc. (www.networkrobots.com) |
| * |
| * Further development of this code funded by Astaro AG (http://www.astaro.com) |
| * |
| * This software may be used and distributed according to the terms |
| * of the GNU General Public License, incorporated herein by reference. |
| * |
| * Derived from ip_conntrack_netlink.c: Port by Pablo Neira Ayuso (05/11/14) |
| */ |
| |
| #include <linux/init.h> |
| #include <linux/module.h> |
| #include <linux/kernel.h> |
| #include <linux/types.h> |
| #include <linux/timer.h> |
| #include <linux/skbuff.h> |
| #include <linux/errno.h> |
| #include <linux/netlink.h> |
| #include <linux/spinlock.h> |
| #include <linux/notifier.h> |
| |
| #include <linux/netfilter.h> |
| #include <net/netfilter/nf_conntrack.h> |
| #include <net/netfilter/nf_conntrack_core.h> |
| #include <net/netfilter/nf_conntrack_helper.h> |
| #include <net/netfilter/nf_conntrack_l3proto.h> |
| #include <net/netfilter/nf_conntrack_protocol.h> |
| #include <linux/netfilter_ipv4/ip_nat_protocol.h> |
| |
| #include <linux/netfilter/nfnetlink.h> |
| #include <linux/netfilter/nfnetlink_conntrack.h> |
| |
| MODULE_LICENSE("GPL"); |
| |
| static char __initdata version[] = "0.93"; |
| |
| #if 0 |
| #define DEBUGP printk |
| #else |
| #define DEBUGP(format, args...) |
| #endif |
| |
| |
| static inline int |
| ctnetlink_dump_tuples_proto(struct sk_buff *skb, |
| const struct nf_conntrack_tuple *tuple) |
| { |
| struct nf_conntrack_protocol *proto; |
| int ret = 0; |
| |
| NFA_PUT(skb, CTA_PROTO_NUM, sizeof(u_int8_t), &tuple->dst.protonum); |
| |
| /* If no protocol helper is found, this function will return the |
| * generic protocol helper, so proto won't *ever* be NULL */ |
| proto = nf_ct_proto_find_get(tuple->src.l3num, tuple->dst.protonum); |
| if (likely(proto->tuple_to_nfattr)) |
| ret = proto->tuple_to_nfattr(skb, tuple); |
| |
| nf_ct_proto_put(proto); |
| |
| return ret; |
| |
| nfattr_failure: |
| return -1; |
| } |
| |
| static inline int |
| ctnetlink_dump_tuples(struct sk_buff *skb, |
| const struct nf_conntrack_tuple *tuple) |
| { |
| struct nfattr *nest_parms; |
| struct nf_conntrack_l3proto *l3proto; |
| int ret = 0; |
| |
| l3proto = nf_ct_l3proto_find_get(tuple->src.l3num); |
| |
| nest_parms = NFA_NEST(skb, CTA_TUPLE_IP); |
| if (likely(l3proto->tuple_to_nfattr)) |
| ret = l3proto->tuple_to_nfattr(skb, tuple); |
| NFA_NEST_END(skb, nest_parms); |
| |
| nf_ct_l3proto_put(l3proto); |
| |
| if (unlikely(ret < 0)) |
| return ret; |
| |
| nest_parms = NFA_NEST(skb, CTA_TUPLE_PROTO); |
| ret = ctnetlink_dump_tuples_proto(skb, tuple); |
| NFA_NEST_END(skb, nest_parms); |
| |
| return ret; |
| |
| nfattr_failure: |
| return -1; |
| } |
| |
| static inline int |
| ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct) |
| { |
| u_int32_t status = htonl((u_int32_t) ct->status); |
| NFA_PUT(skb, CTA_STATUS, sizeof(status), &status); |
| return 0; |
| |
| nfattr_failure: |
| return -1; |
| } |
| |
| static inline int |
| ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct) |
| { |
| long timeout_l = ct->timeout.expires - jiffies; |
| u_int32_t timeout; |
| |
| if (timeout_l < 0) |
| timeout = 0; |
| else |
| timeout = htonl(timeout_l / HZ); |
| |
| NFA_PUT(skb, CTA_TIMEOUT, sizeof(timeout), &timeout); |
| return 0; |
| |
| nfattr_failure: |
| return -1; |
| } |
| |
| static inline int |
| ctnetlink_dump_protoinfo(struct sk_buff *skb, const struct nf_conn *ct) |
| { |
| struct nf_conntrack_protocol *proto = nf_ct_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num, ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum); |
| struct nfattr *nest_proto; |
| int ret; |
| |
| if (!proto->to_nfattr) { |
| nf_ct_proto_put(proto); |
| return 0; |
| } |
| |
| nest_proto = NFA_NEST(skb, CTA_PROTOINFO); |
| |
| ret = proto->to_nfattr(skb, nest_proto, ct); |
| |
| nf_ct_proto_put(proto); |
| |
| NFA_NEST_END(skb, nest_proto); |
| |
| return ret; |
| |
| nfattr_failure: |
| return -1; |
| } |
| |
| static inline int |
| ctnetlink_dump_helpinfo(struct sk_buff *skb, const struct nf_conn *ct) |
| { |
| struct nfattr *nest_helper; |
| const struct nf_conn_help *help = nfct_help(ct); |
| |
| if (!help || !help->helper) |
| return 0; |
| |
| nest_helper = NFA_NEST(skb, CTA_HELP); |
| NFA_PUT(skb, CTA_HELP_NAME, strlen(help->helper->name), help->helper->name); |
| |
| if (help->helper->to_nfattr) |
| help->helper->to_nfattr(skb, ct); |
| |
| NFA_NEST_END(skb, nest_helper); |
| |
| return 0; |
| |
| nfattr_failure: |
| return -1; |
| } |
| |
| #ifdef CONFIG_NF_CT_ACCT |
| static inline 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 nfattr *nest_count = NFA_NEST(skb, type); |
| u_int32_t tmp; |
| |
| tmp = htonl(ct->counters[dir].packets); |
| NFA_PUT(skb, CTA_COUNTERS32_PACKETS, sizeof(u_int32_t), &tmp); |
| |
| tmp = htonl(ct->counters[dir].bytes); |
| NFA_PUT(skb, CTA_COUNTERS32_BYTES, sizeof(u_int32_t), &tmp); |
| |
| NFA_NEST_END(skb, nest_count); |
| |
| return 0; |
| |
| nfattr_failure: |
| return -1; |
| } |
| #else |
| #define ctnetlink_dump_counters(a, b, c) (0) |
| #endif |
| |
| #ifdef CONFIG_NF_CONNTRACK_MARK |
| static inline int |
| ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct) |
| { |
| u_int32_t mark = htonl(ct->mark); |
| |
| NFA_PUT(skb, CTA_MARK, sizeof(u_int32_t), &mark); |
| return 0; |
| |
| nfattr_failure: |
| return -1; |
| } |
| #else |
| #define ctnetlink_dump_mark(a, b) (0) |
| #endif |
| |
| static inline int |
| ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct) |
| { |
| u_int32_t id = htonl(ct->id); |
| NFA_PUT(skb, CTA_ID, sizeof(u_int32_t), &id); |
| return 0; |
| |
| nfattr_failure: |
| return -1; |
| } |
| |
| static inline int |
| ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct) |
| { |
| u_int32_t use = htonl(atomic_read(&ct->ct_general.use)); |
| |
| NFA_PUT(skb, CTA_USE, sizeof(u_int32_t), &use); |
| return 0; |
| |
| nfattr_failure: |
| return -1; |
| } |
| |
| #define tuple(ct, dir) (&(ct)->tuplehash[dir].tuple) |
| |
| static 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 nfattr *nest_parms; |
| unsigned char *b; |
| |
| b = skb->tail; |
| |
| event |= NFNL_SUBSYS_CTNETLINK << 8; |
| nlh = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg)); |
| nfmsg = NLMSG_DATA(nlh); |
| |
| nlh->nlmsg_flags = (nowait && pid) ? NLM_F_MULTI : 0; |
| nfmsg->nfgen_family = |
| ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num; |
| nfmsg->version = NFNETLINK_V0; |
| nfmsg->res_id = 0; |
| |
| nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG); |
| if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0) |
| goto nfattr_failure; |
| NFA_NEST_END(skb, nest_parms); |
| |
| nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY); |
| if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0) |
| goto nfattr_failure; |
| NFA_NEST_END(skb, nest_parms); |
| |
| if (ctnetlink_dump_status(skb, ct) < 0 || |
| ctnetlink_dump_timeout(skb, ct) < 0 || |
| ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 || |
| ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0 || |
| ctnetlink_dump_protoinfo(skb, ct) < 0 || |
| ctnetlink_dump_helpinfo(skb, ct) < 0 || |
| ctnetlink_dump_mark(skb, ct) < 0 || |
| ctnetlink_dump_id(skb, ct) < 0 || |
| ctnetlink_dump_use(skb, ct) < 0) |
| goto nfattr_failure; |
| |
| nlh->nlmsg_len = skb->tail - b; |
| return skb->len; |
| |
| nlmsg_failure: |
| nfattr_failure: |
| skb_trim(skb, b - skb->data); |
| return -1; |
| } |
| |
| #ifdef CONFIG_NF_CONNTRACK_EVENTS |
| static int ctnetlink_conntrack_event(struct notifier_block *this, |
| unsigned long events, void *ptr) |
| { |
| struct nlmsghdr *nlh; |
| struct nfgenmsg *nfmsg; |
| struct nfattr *nest_parms; |
| struct nf_conn *ct = (struct nf_conn *)ptr; |
| struct sk_buff *skb; |
| unsigned int type; |
| unsigned char *b; |
| unsigned int flags = 0, group; |
| |
| /* ignore our fake conntrack entry */ |
| if (ct == &nf_conntrack_untracked) |
| return NOTIFY_DONE; |
| |
| if (events & IPCT_DESTROY) { |
| type = IPCTNL_MSG_CT_DELETE; |
| group = NFNLGRP_CONNTRACK_DESTROY; |
| } else if (events & (IPCT_NEW | IPCT_RELATED)) { |
| type = IPCTNL_MSG_CT_NEW; |
| flags = NLM_F_CREATE|NLM_F_EXCL; |
| /* dump everything */ |
| events = ~0UL; |
| group = NFNLGRP_CONNTRACK_NEW; |
| } else if (events & (IPCT_STATUS | |
| IPCT_PROTOINFO | |
| IPCT_HELPER | |
| IPCT_HELPINFO | |
| IPCT_NATINFO)) { |
| type = IPCTNL_MSG_CT_NEW; |
| group = NFNLGRP_CONNTRACK_UPDATE; |
| } else |
| return NOTIFY_DONE; |
| |
| if (!nfnetlink_has_listeners(group)) |
| return NOTIFY_DONE; |
| |
| skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC); |
| if (!skb) |
| return NOTIFY_DONE; |
| |
| b = skb->tail; |
| |
| type |= NFNL_SUBSYS_CTNETLINK << 8; |
| nlh = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg)); |
| nfmsg = NLMSG_DATA(nlh); |
| |
| nlh->nlmsg_flags = flags; |
| nfmsg->nfgen_family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num; |
| nfmsg->version = NFNETLINK_V0; |
| nfmsg->res_id = 0; |
| |
| nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG); |
| if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0) |
| goto nfattr_failure; |
| NFA_NEST_END(skb, nest_parms); |
| |
| nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY); |
| if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0) |
| goto nfattr_failure; |
| NFA_NEST_END(skb, nest_parms); |
| |
| /* NAT stuff is now a status flag */ |
| if ((events & IPCT_STATUS || events & IPCT_NATINFO) |
| && ctnetlink_dump_status(skb, ct) < 0) |
| goto nfattr_failure; |
| if (events & IPCT_REFRESH |
| && ctnetlink_dump_timeout(skb, ct) < 0) |
| goto nfattr_failure; |
| if (events & IPCT_PROTOINFO |
| && ctnetlink_dump_protoinfo(skb, ct) < 0) |
| goto nfattr_failure; |
| if (events & IPCT_HELPINFO |
| && ctnetlink_dump_helpinfo(skb, ct) < 0) |
| goto nfattr_failure; |
| |
| if (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 || |
| ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0) |
| goto nfattr_failure; |
| |
| nlh->nlmsg_len = skb->tail - b; |
| nfnetlink_send(skb, 0, group, 0); |
| return NOTIFY_DONE; |
| |
| nlmsg_failure: |
| nfattr_failure: |
| kfree_skb(skb); |
| return NOTIFY_DONE; |
| } |
| #endif /* CONFIG_NF_CONNTRACK_EVENTS */ |
| |
| static int ctnetlink_done(struct netlink_callback *cb) |
| { |
| DEBUGP("entered %s\n", __FUNCTION__); |
| return 0; |
| } |
| |
| #define L3PROTO(ct) ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num |
| |
| static int |
| ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb) |
| { |
| struct nf_conn *ct = NULL; |
| struct nf_conntrack_tuple_hash *h; |
| struct list_head *i; |
| u_int32_t *id = (u_int32_t *) &cb->args[1]; |
| struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh); |
| u_int8_t l3proto = nfmsg->nfgen_family; |
| |
| DEBUGP("entered %s, last bucket=%lu id=%u\n", __FUNCTION__, |
| cb->args[0], *id); |
| |
| read_lock_bh(&nf_conntrack_lock); |
| for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++, *id = 0) { |
| list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) { |
| h = (struct nf_conntrack_tuple_hash *) i; |
| if (DIRECTION(h) != IP_CT_DIR_ORIGINAL) |
| continue; |
| ct = nf_ct_tuplehash_to_ctrack(h); |
| /* Dump entries of a given L3 protocol number. |
| * If it is not specified, ie. l3proto == 0, |
| * then dump everything. */ |
| if (l3proto && L3PROTO(ct) != l3proto) |
| continue; |
| if (ct->id <= *id) |
| continue; |
| if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid, |
| cb->nlh->nlmsg_seq, |
| IPCTNL_MSG_CT_NEW, |
| 1, ct) < 0) |
| goto out; |
| *id = ct->id; |
| } |
| } |
| out: |
| read_unlock_bh(&nf_conntrack_lock); |
| |
| DEBUGP("leaving, last bucket=%lu id=%u\n", cb->args[0], *id); |
| |
| return skb->len; |
| } |
| |
| #ifdef CONFIG_NF_CT_ACCT |
| static int |
| ctnetlink_dump_table_w(struct sk_buff *skb, struct netlink_callback *cb) |
| { |
| struct nf_conn *ct = NULL; |
| struct nf_conntrack_tuple_hash *h; |
| struct list_head *i; |
| u_int32_t *id = (u_int32_t *) &cb->args[1]; |
| struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh); |
| u_int8_t l3proto = nfmsg->nfgen_family; |
| |
| DEBUGP("entered %s, last bucket=%u id=%u\n", __FUNCTION__, |
| cb->args[0], *id); |
| |
| write_lock_bh(&nf_conntrack_lock); |
| for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++, *id = 0) { |
| list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) { |
| h = (struct nf_conntrack_tuple_hash *) i; |
| if (DIRECTION(h) != IP_CT_DIR_ORIGINAL) |
| continue; |
| ct = nf_ct_tuplehash_to_ctrack(h); |
| if (l3proto && L3PROTO(ct) != l3proto) |
| continue; |
| if (ct->id <= *id) |
| continue; |
| if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid, |
| cb->nlh->nlmsg_seq, |
| IPCTNL_MSG_CT_NEW, |
| 1, ct) < 0) |
| goto out; |
| *id = ct->id; |
| |
| memset(&ct->counters, 0, sizeof(ct->counters)); |
| } |
| } |
| out: |
| write_unlock_bh(&nf_conntrack_lock); |
| |
| DEBUGP("leaving, last bucket=%lu id=%u\n", cb->args[0], *id); |
| |
| return skb->len; |
| } |
| #endif |
| |
| static inline int |
| ctnetlink_parse_tuple_ip(struct nfattr *attr, struct nf_conntrack_tuple *tuple) |
| { |
| struct nfattr *tb[CTA_IP_MAX]; |
| struct nf_conntrack_l3proto *l3proto; |
| int ret = 0; |
| |
| DEBUGP("entered %s\n", __FUNCTION__); |
| |
| nfattr_parse_nested(tb, CTA_IP_MAX, attr); |
| |
| l3proto = nf_ct_l3proto_find_get(tuple->src.l3num); |
| |
| if (likely(l3proto->nfattr_to_tuple)) |
| ret = l3proto->nfattr_to_tuple(tb, tuple); |
| |
| nf_ct_l3proto_put(l3proto); |
| |
| DEBUGP("leaving\n"); |
| |
| return ret; |
| } |
| |
| static const size_t cta_min_proto[CTA_PROTO_MAX] = { |
| [CTA_PROTO_NUM-1] = sizeof(u_int8_t), |
| }; |
| |
| static inline int |
| ctnetlink_parse_tuple_proto(struct nfattr *attr, |
| struct nf_conntrack_tuple *tuple) |
| { |
| struct nfattr *tb[CTA_PROTO_MAX]; |
| struct nf_conntrack_protocol *proto; |
| int ret = 0; |
| |
| DEBUGP("entered %s\n", __FUNCTION__); |
| |
| nfattr_parse_nested(tb, CTA_PROTO_MAX, attr); |
| |
| if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto)) |
| return -EINVAL; |
| |
| if (!tb[CTA_PROTO_NUM-1]) |
| return -EINVAL; |
| tuple->dst.protonum = *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_NUM-1]); |
| |
| proto = nf_ct_proto_find_get(tuple->src.l3num, tuple->dst.protonum); |
| |
| if (likely(proto->nfattr_to_tuple)) |
| ret = proto->nfattr_to_tuple(tb, tuple); |
| |
| nf_ct_proto_put(proto); |
| |
| return ret; |
| } |
| |
| static inline int |
| ctnetlink_parse_tuple(struct nfattr *cda[], struct nf_conntrack_tuple *tuple, |
| enum ctattr_tuple type, u_int8_t l3num) |
| { |
| struct nfattr *tb[CTA_TUPLE_MAX]; |
| int err; |
| |
| DEBUGP("entered %s\n", __FUNCTION__); |
| |
| memset(tuple, 0, sizeof(*tuple)); |
| |
| nfattr_parse_nested(tb, CTA_TUPLE_MAX, cda[type-1]); |
| |
| if (!tb[CTA_TUPLE_IP-1]) |
| return -EINVAL; |
| |
| tuple->src.l3num = l3num; |
| |
| err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP-1], tuple); |
| if (err < 0) |
| return err; |
| |
| if (!tb[CTA_TUPLE_PROTO-1]) |
| return -EINVAL; |
| |
| err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO-1], tuple); |
| if (err < 0) |
| return err; |
| |
| /* orig and expect tuples get DIR_ORIGINAL */ |
| if (type == CTA_TUPLE_REPLY) |
| tuple->dst.dir = IP_CT_DIR_REPLY; |
| else |
| tuple->dst.dir = IP_CT_DIR_ORIGINAL; |
| |
| NF_CT_DUMP_TUPLE(tuple); |
| |
| DEBUGP("leaving\n"); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_IP_NF_NAT_NEEDED |
| static const size_t cta_min_protonat[CTA_PROTONAT_MAX] = { |
| [CTA_PROTONAT_PORT_MIN-1] = sizeof(u_int16_t), |
| [CTA_PROTONAT_PORT_MAX-1] = sizeof(u_int16_t), |
| }; |
| |
| static int ctnetlink_parse_nat_proto(struct nfattr *attr, |
| const struct nf_conn *ct, |
| struct ip_nat_range *range) |
| { |
| struct nfattr *tb[CTA_PROTONAT_MAX]; |
| struct ip_nat_protocol *npt; |
| |
| DEBUGP("entered %s\n", __FUNCTION__); |
| |
| nfattr_parse_nested(tb, CTA_PROTONAT_MAX, attr); |
| |
| if (nfattr_bad_size(tb, CTA_PROTONAT_MAX, cta_min_protonat)) |
| return -EINVAL; |
| |
| npt = ip_nat_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum); |
| |
| if (!npt->nfattr_to_range) { |
| ip_nat_proto_put(npt); |
| return 0; |
| } |
| |
| /* nfattr_to_range returns 1 if it parsed, 0 if not, neg. on error */ |
| if (npt->nfattr_to_range(tb, range) > 0) |
| range->flags |= IP_NAT_RANGE_PROTO_SPECIFIED; |
| |
| ip_nat_proto_put(npt); |
| |
| DEBUGP("leaving\n"); |
| return 0; |
| } |
| |
| static const size_t cta_min_nat[CTA_NAT_MAX] = { |
| [CTA_NAT_MINIP-1] = sizeof(u_int32_t), |
| [CTA_NAT_MAXIP-1] = sizeof(u_int32_t), |
| }; |
| |
| static inline int |
| ctnetlink_parse_nat(struct nfattr *cda[], |
| const struct nf_conn *ct, struct ip_nat_range *range) |
| { |
| struct nfattr *tb[CTA_NAT_MAX]; |
| int err; |
| |
| DEBUGP("entered %s\n", __FUNCTION__); |
| |
| memset(range, 0, sizeof(*range)); |
| |
| nfattr_parse_nested(tb, CTA_NAT_MAX, cda[CTA_NAT-1]); |
| |
| if (nfattr_bad_size(tb, CTA_NAT_MAX, cta_min_nat)) |
| return -EINVAL; |
| |
| if (tb[CTA_NAT_MINIP-1]) |
| range->min_ip = *(u_int32_t *)NFA_DATA(tb[CTA_NAT_MINIP-1]); |
| |
| if (!tb[CTA_NAT_MAXIP-1]) |
| range->max_ip = range->min_ip; |
| else |
| range->max_ip = *(u_int32_t *)NFA_DATA(tb[CTA_NAT_MAXIP-1]); |
| |
| if (range->min_ip) |
| range->flags |= IP_NAT_RANGE_MAP_IPS; |
| |
| if (!tb[CTA_NAT_PROTO-1]) |
| return 0; |
| |
| err = ctnetlink_parse_nat_proto(tb[CTA_NAT_PROTO-1], ct, range); |
| if (err < 0) |
| return err; |
| |
| DEBUGP("leaving\n"); |
| return 0; |
| } |
| #endif |
| |
| static inline int |
| ctnetlink_parse_help(struct nfattr *attr, char **helper_name) |
| { |
| struct nfattr *tb[CTA_HELP_MAX]; |
| |
| DEBUGP("entered %s\n", __FUNCTION__); |
| |
| nfattr_parse_nested(tb, CTA_HELP_MAX, attr); |
| |
| if (!tb[CTA_HELP_NAME-1]) |
| return -EINVAL; |
| |
| *helper_name = NFA_DATA(tb[CTA_HELP_NAME-1]); |
| |
| return 0; |
| } |
| |
| static const size_t cta_min[CTA_MAX] = { |
| [CTA_STATUS-1] = sizeof(u_int32_t), |
| [CTA_TIMEOUT-1] = sizeof(u_int32_t), |
| [CTA_MARK-1] = sizeof(u_int32_t), |
| [CTA_USE-1] = sizeof(u_int32_t), |
| [CTA_ID-1] = sizeof(u_int32_t) |
| }; |
| |
| static int |
| ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb, |
| struct nlmsghdr *nlh, struct nfattr *cda[], int *errp) |
| { |
| struct nf_conntrack_tuple_hash *h; |
| struct nf_conntrack_tuple tuple; |
| struct nf_conn *ct; |
| struct nfgenmsg *nfmsg = NLMSG_DATA(nlh); |
| u_int8_t u3 = nfmsg->nfgen_family; |
| int err = 0; |
| |
| DEBUGP("entered %s\n", __FUNCTION__); |
| |
| if (nfattr_bad_size(cda, CTA_MAX, cta_min)) |
| return -EINVAL; |
| |
| if (cda[CTA_TUPLE_ORIG-1]) |
| err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3); |
| else if (cda[CTA_TUPLE_REPLY-1]) |
| err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3); |
| else { |
| /* Flush the whole table */ |
| nf_conntrack_flush(); |
| return 0; |
| } |
| |
| if (err < 0) |
| return err; |
| |
| h = nf_conntrack_find_get(&tuple, NULL); |
| if (!h) { |
| DEBUGP("tuple not found in conntrack hash\n"); |
| return -ENOENT; |
| } |
| |
| ct = nf_ct_tuplehash_to_ctrack(h); |
| |
| if (cda[CTA_ID-1]) { |
| u_int32_t id = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_ID-1])); |
| if (ct->id != id) { |
| nf_ct_put(ct); |
| return -ENOENT; |
| } |
| } |
| if (del_timer(&ct->timeout)) |
| ct->timeout.function((unsigned long)ct); |
| |
| nf_ct_put(ct); |
| DEBUGP("leaving\n"); |
| |
| return 0; |
| } |
| |
| static int |
| ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb, |
| struct nlmsghdr *nlh, struct nfattr *cda[], int *errp) |
| { |
| struct nf_conntrack_tuple_hash *h; |
| struct nf_conntrack_tuple tuple; |
| struct nf_conn *ct; |
| struct sk_buff *skb2 = NULL; |
| struct nfgenmsg *nfmsg = NLMSG_DATA(nlh); |
| u_int8_t u3 = nfmsg->nfgen_family; |
| int err = 0; |
| |
| DEBUGP("entered %s\n", __FUNCTION__); |
| |
| if (nlh->nlmsg_flags & NLM_F_DUMP) { |
| u32 rlen; |
| |
| if (NFNL_MSG_TYPE(nlh->nlmsg_type) == |
| IPCTNL_MSG_CT_GET_CTRZERO) { |
| #ifdef CONFIG_NF_CT_ACCT |
| if ((*errp = netlink_dump_start(ctnl, skb, nlh, |
| ctnetlink_dump_table_w, |
| ctnetlink_done)) != 0) |
| return -EINVAL; |
| #else |
| return -ENOTSUPP; |
| #endif |
| } else { |
| if ((*errp = netlink_dump_start(ctnl, skb, nlh, |
| ctnetlink_dump_table, |
| ctnetlink_done)) != 0) |
| return -EINVAL; |
| } |
| |
| rlen = NLMSG_ALIGN(nlh->nlmsg_len); |
| if (rlen > skb->len) |
| rlen = skb->len; |
| skb_pull(skb, rlen); |
| return 0; |
| } |
| |
| if (nfattr_bad_size(cda, CTA_MAX, cta_min)) |
| return -EINVAL; |
| |
| if (cda[CTA_TUPLE_ORIG-1]) |
| err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3); |
| else if (cda[CTA_TUPLE_REPLY-1]) |
| err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3); |
| else |
| return -EINVAL; |
| |
| if (err < 0) |
| return err; |
| |
| h = nf_conntrack_find_get(&tuple, NULL); |
| if (!h) { |
| DEBUGP("tuple not found in conntrack hash"); |
| return -ENOENT; |
| } |
| DEBUGP("tuple found\n"); |
| ct = nf_ct_tuplehash_to_ctrack(h); |
| |
| err = -ENOMEM; |
| skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); |
| if (!skb2) { |
| nf_ct_put(ct); |
| return -ENOMEM; |
| } |
| NETLINK_CB(skb2).dst_pid = NETLINK_CB(skb).pid; |
| |
| 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; |
| |
| DEBUGP("leaving\n"); |
| return 0; |
| |
| free: |
| kfree_skb(skb2); |
| out: |
| return err; |
| } |
| |
| static inline int |
| ctnetlink_change_status(struct nf_conn *ct, struct nfattr *cda[]) |
| { |
| unsigned long d; |
| unsigned status = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_STATUS-1])); |
| d = ct->status ^ status; |
| |
| if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING)) |
| /* unchangeable */ |
| return -EINVAL; |
| |
| if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY)) |
| /* SEEN_REPLY bit can only be set */ |
| return -EINVAL; |
| |
| |
| if (d & IPS_ASSURED && !(status & IPS_ASSURED)) |
| /* ASSURED bit can only be set */ |
| return -EINVAL; |
| |
| if (cda[CTA_NAT-1]) { |
| #ifndef CONFIG_IP_NF_NAT_NEEDED |
| return -EINVAL; |
| #else |
| unsigned int hooknum; |
| struct ip_nat_range range; |
| |
| if (ctnetlink_parse_nat(cda, ct, &range) < 0) |
| return -EINVAL; |
| |
| DEBUGP("NAT: %u.%u.%u.%u-%u.%u.%u.%u:%u-%u\n", |
| NIPQUAD(range.min_ip), NIPQUAD(range.max_ip), |
| htons(range.min.all), htons(range.max.all)); |
| |
| /* This is tricky but it works. ip_nat_setup_info needs the |
| * hook number as parameter, so let's do the correct |
| * conversion and run away */ |
| if (status & IPS_SRC_NAT_DONE) |
| hooknum = NF_IP_POST_ROUTING; /* IP_NAT_MANIP_SRC */ |
| else if (status & IPS_DST_NAT_DONE) |
| hooknum = NF_IP_PRE_ROUTING; /* IP_NAT_MANIP_DST */ |
| else |
| return -EINVAL; /* Missing NAT flags */ |
| |
| DEBUGP("NAT status: %lu\n", |
| status & (IPS_NAT_MASK | IPS_NAT_DONE_MASK)); |
| |
| if (ip_nat_initialized(ct, HOOK2MANIP(hooknum))) |
| return -EEXIST; |
| ip_nat_setup_info(ct, &range, hooknum); |
| |
| DEBUGP("NAT status after setup_info: %lu\n", |
| ct->status & (IPS_NAT_MASK | IPS_NAT_DONE_MASK)); |
| #endif |
| } |
| |
| /* Be careful here, modifying NAT bits can screw up things, |
| * so don't let users modify them directly if they don't pass |
| * ip_nat_range. */ |
| ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK); |
| return 0; |
| } |
| |
| |
| static inline int |
| ctnetlink_change_helper(struct nf_conn *ct, struct nfattr *cda[]) |
| { |
| struct nf_conntrack_helper *helper; |
| struct nf_conn_help *help = nfct_help(ct); |
| char *helpname; |
| int err; |
| |
| DEBUGP("entered %s\n", __FUNCTION__); |
| |
| if (!help) { |
| /* FIXME: we need to reallocate and rehash */ |
| return -EBUSY; |
| } |
| |
| /* don't change helper of sibling connections */ |
| if (ct->master) |
| return -EINVAL; |
| |
| err = ctnetlink_parse_help(cda[CTA_HELP-1], &helpname); |
| if (err < 0) |
| return err; |
| |
| helper = __nf_conntrack_helper_find_byname(helpname); |
| if (!helper) { |
| if (!strcmp(helpname, "")) |
| helper = NULL; |
| else |
| return -EINVAL; |
| } |
| |
| if (help->helper) { |
| if (!helper) { |
| /* we had a helper before ... */ |
| nf_ct_remove_expectations(ct); |
| help->helper = NULL; |
| } else { |
| /* need to zero data of old helper */ |
| memset(&help->help, 0, sizeof(help->help)); |
| } |
| } |
| |
| help->helper = helper; |
| |
| return 0; |
| } |
| |
| static inline int |
| ctnetlink_change_timeout(struct nf_conn *ct, struct nfattr *cda[]) |
| { |
| u_int32_t timeout = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_TIMEOUT-1])); |
| |
| if (!del_timer(&ct->timeout)) |
| return -ETIME; |
| |
| ct->timeout.expires = jiffies + timeout * HZ; |
| add_timer(&ct->timeout); |
| |
| return 0; |
| } |
| |
| static inline int |
| ctnetlink_change_protoinfo(struct nf_conn *ct, struct nfattr *cda[]) |
| { |
| struct nfattr *tb[CTA_PROTOINFO_MAX], *attr = cda[CTA_PROTOINFO-1]; |
| struct nf_conntrack_protocol *proto; |
| u_int16_t npt = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum; |
| u_int16_t l3num = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num; |
| int err = 0; |
| |
| nfattr_parse_nested(tb, CTA_PROTOINFO_MAX, attr); |
| |
| proto = nf_ct_proto_find_get(l3num, npt); |
| |
| if (proto->from_nfattr) |
| err = proto->from_nfattr(tb, ct); |
| nf_ct_proto_put(proto); |
| |
| return err; |
| } |
| |
| static int |
| ctnetlink_change_conntrack(struct nf_conn *ct, struct nfattr *cda[]) |
| { |
| int err; |
| |
| DEBUGP("entered %s\n", __FUNCTION__); |
| |
| if (cda[CTA_HELP-1]) { |
| err = ctnetlink_change_helper(ct, cda); |
| if (err < 0) |
| return err; |
| } |
| |
| if (cda[CTA_TIMEOUT-1]) { |
| err = ctnetlink_change_timeout(ct, cda); |
| if (err < 0) |
| return err; |
| } |
| |
| if (cda[CTA_STATUS-1]) { |
| err = ctnetlink_change_status(ct, cda); |
| if (err < 0) |
| return err; |
| } |
| |
| if (cda[CTA_PROTOINFO-1]) { |
| err = ctnetlink_change_protoinfo(ct, cda); |
| if (err < 0) |
| return err; |
| } |
| |
| #if defined(CONFIG_IP_NF_CONNTRACK_MARK) |
| if (cda[CTA_MARK-1]) |
| ct->mark = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_MARK-1])); |
| #endif |
| |
| DEBUGP("all done\n"); |
| return 0; |
| } |
| |
| static int |
| ctnetlink_create_conntrack(struct nfattr *cda[], |
| struct nf_conntrack_tuple *otuple, |
| struct nf_conntrack_tuple *rtuple) |
| { |
| struct nf_conn *ct; |
| int err = -EINVAL; |
| |
| DEBUGP("entered %s\n", __FUNCTION__); |
| |
| ct = nf_conntrack_alloc(otuple, rtuple); |
| if (ct == NULL || IS_ERR(ct)) |
| return -ENOMEM; |
| |
| if (!cda[CTA_TIMEOUT-1]) |
| goto err; |
| ct->timeout.expires = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_TIMEOUT-1])); |
| |
| ct->timeout.expires = jiffies + ct->timeout.expires * HZ; |
| ct->status |= IPS_CONFIRMED; |
| |
| err = ctnetlink_change_status(ct, cda); |
| if (err < 0) |
| goto err; |
| |
| if (cda[CTA_PROTOINFO-1]) { |
| err = ctnetlink_change_protoinfo(ct, cda); |
| if (err < 0) |
| return err; |
| } |
| |
| #if defined(CONFIG_IP_NF_CONNTRACK_MARK) |
| if (cda[CTA_MARK-1]) |
| ct->mark = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_MARK-1])); |
| #endif |
| |
| add_timer(&ct->timeout); |
| nf_conntrack_hash_insert(ct); |
| |
| DEBUGP("conntrack with id %u inserted\n", ct->id); |
| 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 nfattr *cda[], int *errp) |
| { |
| struct nf_conntrack_tuple otuple, rtuple; |
| struct nf_conntrack_tuple_hash *h = NULL; |
| struct nfgenmsg *nfmsg = NLMSG_DATA(nlh); |
| u_int8_t u3 = nfmsg->nfgen_family; |
| int err = 0; |
| |
| DEBUGP("entered %s\n", __FUNCTION__); |
| |
| if (nfattr_bad_size(cda, CTA_MAX, cta_min)) |
| return -EINVAL; |
| |
| if (cda[CTA_TUPLE_ORIG-1]) { |
| err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3); |
| if (err < 0) |
| return err; |
| } |
| |
| if (cda[CTA_TUPLE_REPLY-1]) { |
| err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3); |
| if (err < 0) |
| return err; |
| } |
| |
| write_lock_bh(&nf_conntrack_lock); |
| if (cda[CTA_TUPLE_ORIG-1]) |
| h = __nf_conntrack_find(&otuple, NULL); |
| else if (cda[CTA_TUPLE_REPLY-1]) |
| h = __nf_conntrack_find(&rtuple, NULL); |
| |
| if (h == NULL) { |
| write_unlock_bh(&nf_conntrack_lock); |
| DEBUGP("no such conntrack, create new\n"); |
| err = -ENOENT; |
| if (nlh->nlmsg_flags & NLM_F_CREATE) |
| err = ctnetlink_create_conntrack(cda, &otuple, &rtuple); |
| return err; |
| } |
| /* implicit 'else' */ |
| |
| /* we only allow nat config for new conntracks */ |
| if (cda[CTA_NAT-1]) { |
| err = -EINVAL; |
| goto out_unlock; |
| } |
| |
| /* We manipulate the conntrack inside the global conntrack table lock, |
| * so there's no need to increase the refcount */ |
| DEBUGP("conntrack found\n"); |
| err = -EEXIST; |
| if (!(nlh->nlmsg_flags & NLM_F_EXCL)) |
| err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h), cda); |
| |
| out_unlock: |
| write_unlock_bh(&nf_conntrack_lock); |
| return err; |
| } |
| |
| /*********************************************************************** |
| * EXPECT |
| ***********************************************************************/ |
| |
| static inline int |
| ctnetlink_exp_dump_tuple(struct sk_buff *skb, |
| const struct nf_conntrack_tuple *tuple, |
| enum ctattr_expect type) |
| { |
| struct nfattr *nest_parms = NFA_NEST(skb, type); |
| |
| if (ctnetlink_dump_tuples(skb, tuple) < 0) |
| goto nfattr_failure; |
| |
| NFA_NEST_END(skb, nest_parms); |
| |
| return 0; |
| |
| nfattr_failure: |
| return -1; |
| } |
| |
| static inline int |
| ctnetlink_exp_dump_expect(struct sk_buff *skb, |
| const struct nf_conntrack_expect *exp) |
| { |
| struct nf_conn *master = exp->master; |
| u_int32_t timeout = htonl((exp->timeout.expires - jiffies) / HZ); |
| u_int32_t id = htonl(exp->id); |
| |
| if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0) |
| goto nfattr_failure; |
| if (ctnetlink_exp_dump_tuple(skb, &exp->mask, CTA_EXPECT_MASK) < 0) |
| goto nfattr_failure; |
| if (ctnetlink_exp_dump_tuple(skb, |
| &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple, |
| CTA_EXPECT_MASTER) < 0) |
| goto nfattr_failure; |
| |
| NFA_PUT(skb, CTA_EXPECT_TIMEOUT, sizeof(timeout), &timeout); |
| NFA_PUT(skb, CTA_EXPECT_ID, sizeof(u_int32_t), &id); |
| |
| return 0; |
| |
| nfattr_failure: |
| return -1; |
| } |
| |
| static 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; |
| |
| b = skb->tail; |
| |
| event |= NFNL_SUBSYS_CTNETLINK_EXP << 8; |
| nlh = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg)); |
| nfmsg = NLMSG_DATA(nlh); |
| |
| nlh->nlmsg_flags = (nowait && pid) ? NLM_F_MULTI : 0; |
| nfmsg->nfgen_family = exp->tuple.src.l3num; |
| nfmsg->version = NFNETLINK_V0; |
| nfmsg->res_id = 0; |
| |
| if (ctnetlink_exp_dump_expect(skb, exp) < 0) |
| goto nfattr_failure; |
| |
| nlh->nlmsg_len = skb->tail - b; |
| return skb->len; |
| |
| nlmsg_failure: |
| nfattr_failure: |
| skb_trim(skb, b - skb->data); |
| return -1; |
| } |
| |
| #ifdef CONFIG_NF_CONNTRACK_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; |
| unsigned char *b; |
| int flags = 0; |
| |
| if (events & IPEXP_NEW) { |
| type = IPCTNL_MSG_EXP_NEW; |
| flags = NLM_F_CREATE|NLM_F_EXCL; |
| } else |
| return NOTIFY_DONE; |
| |
| skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC); |
| if (!skb) |
| return NOTIFY_DONE; |
| |
| b = skb->tail; |
| |
| type |= NFNL_SUBSYS_CTNETLINK_EXP << 8; |
| nlh = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg)); |
| nfmsg = NLMSG_DATA(nlh); |
| |
| nlh->nlmsg_flags = flags; |
| nfmsg->nfgen_family = exp->tuple.src.l3num; |
| nfmsg->version = NFNETLINK_V0; |
| nfmsg->res_id = 0; |
| |
| if (ctnetlink_exp_dump_expect(skb, exp) < 0) |
| goto nfattr_failure; |
| |
| nlh->nlmsg_len = skb->tail - b; |
| nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0); |
| return NOTIFY_DONE; |
| |
| nlmsg_failure: |
| nfattr_failure: |
| kfree_skb(skb); |
| return NOTIFY_DONE; |
| } |
| #endif |
| |
| static int |
| ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb) |
| { |
| struct nf_conntrack_expect *exp = NULL; |
| struct list_head *i; |
| u_int32_t *id = (u_int32_t *) &cb->args[0]; |
| struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh); |
| u_int8_t l3proto = nfmsg->nfgen_family; |
| |
| DEBUGP("entered %s, last id=%llu\n", __FUNCTION__, *id); |
| |
| read_lock_bh(&nf_conntrack_lock); |
| list_for_each_prev(i, &nf_conntrack_expect_list) { |
| exp = (struct nf_conntrack_expect *) i; |
| if (l3proto && exp->tuple.src.l3num != l3proto) |
| continue; |
| if (exp->id <= *id) |
| continue; |
| if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid, |
| cb->nlh->nlmsg_seq, |
| IPCTNL_MSG_EXP_NEW, |
| 1, exp) < 0) |
| goto out; |
| *id = exp->id; |
| } |
| out: |
| read_unlock_bh(&nf_conntrack_lock); |
| |
| DEBUGP("leaving, last id=%llu\n", *id); |
| |
| return skb->len; |
| } |
| |
| static const size_t cta_min_exp[CTA_EXPECT_MAX] = { |
| [CTA_EXPECT_TIMEOUT-1] = sizeof(u_int32_t), |
| [CTA_EXPECT_ID-1] = sizeof(u_int32_t) |
| }; |
| |
| static int |
| ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb, |
| struct nlmsghdr *nlh, struct nfattr *cda[], int *errp) |
| { |
| struct nf_conntrack_tuple tuple; |
| struct nf_conntrack_expect *exp; |
| struct sk_buff *skb2; |
| struct nfgenmsg *nfmsg = NLMSG_DATA(nlh); |
| u_int8_t u3 = nfmsg->nfgen_family; |
| int err = 0; |
| |
| DEBUGP("entered %s\n", __FUNCTION__); |
| |
| if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp)) |
| return -EINVAL; |
| |
| if (nlh->nlmsg_flags & NLM_F_DUMP) { |
| u32 rlen; |
| |
| if ((*errp = netlink_dump_start(ctnl, skb, nlh, |
| ctnetlink_exp_dump_table, |
| ctnetlink_done)) != 0) |
| return -EINVAL; |
| rlen = NLMSG_ALIGN(nlh->nlmsg_len); |
| if (rlen > skb->len) |
| rlen = skb->len; |
| skb_pull(skb, rlen); |
| return 0; |
| } |
| |
| if (cda[CTA_EXPECT_MASTER-1]) |
| err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3); |
| else |
| return -EINVAL; |
| |
| if (err < 0) |
| return err; |
| |
| exp = nf_conntrack_expect_find(&tuple); |
| if (!exp) |
| return -ENOENT; |
| |
| if (cda[CTA_EXPECT_ID-1]) { |
| u_int32_t id = *(u_int32_t *)NFA_DATA(cda[CTA_EXPECT_ID-1]); |
| if (exp->id != ntohl(id)) { |
| nf_conntrack_expect_put(exp); |
| return -ENOENT; |
| } |
| } |
| |
| err = -ENOMEM; |
| skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); |
| if (!skb2) |
| goto out; |
| NETLINK_CB(skb2).dst_pid = NETLINK_CB(skb).pid; |
| |
| err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid, |
| nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW, |
| 1, exp); |
| if (err <= 0) |
| goto free; |
| |
| nf_conntrack_expect_put(exp); |
| |
| return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT); |
| |
| free: |
| kfree_skb(skb2); |
| out: |
| nf_conntrack_expect_put(exp); |
| return err; |
| } |
| |
| static int |
| ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb, |
| struct nlmsghdr *nlh, struct nfattr *cda[], int *errp) |
| { |
| struct nf_conntrack_expect *exp, *tmp; |
| struct nf_conntrack_tuple tuple; |
| struct nf_conntrack_helper *h; |
| struct nfgenmsg *nfmsg = NLMSG_DATA(nlh); |
| u_int8_t u3 = nfmsg->nfgen_family; |
| int err; |
| |
| if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp)) |
| return -EINVAL; |
| |
| if (cda[CTA_EXPECT_TUPLE-1]) { |
| /* delete a single expect by tuple */ |
| err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3); |
| if (err < 0) |
| return err; |
| |
| /* bump usage count to 2 */ |
| exp = nf_conntrack_expect_find(&tuple); |
| if (!exp) |
| return -ENOENT; |
| |
| if (cda[CTA_EXPECT_ID-1]) { |
| u_int32_t id = |
| *(u_int32_t *)NFA_DATA(cda[CTA_EXPECT_ID-1]); |
| if (exp->id != ntohl(id)) { |
| nf_conntrack_expect_put(exp); |
| return -ENOENT; |
| } |
| } |
| |
| /* after list removal, usage count == 1 */ |
| nf_conntrack_unexpect_related(exp); |
| /* have to put what we 'get' above. |
| * after this line usage count == 0 */ |
| nf_conntrack_expect_put(exp); |
| } else if (cda[CTA_EXPECT_HELP_NAME-1]) { |
| char *name = NFA_DATA(cda[CTA_EXPECT_HELP_NAME-1]); |
| |
| /* delete all expectations for this helper */ |
| write_lock_bh(&nf_conntrack_lock); |
| h = __nf_conntrack_helper_find_byname(name); |
| if (!h) { |
| write_unlock_bh(&nf_conntrack_lock); |
| return -EINVAL; |
| } |
| list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list, |
| list) { |
| struct nf_conn_help *m_help = nfct_help(exp->master); |
| if (m_help->helper == h |
| && del_timer(&exp->timeout)) { |
| nf_ct_unlink_expect(exp); |
| nf_conntrack_expect_put(exp); |
| } |
| } |
| write_unlock_bh(&nf_conntrack_lock); |
| } else { |
| /* This basically means we have to flush everything*/ |
| write_lock_bh(&nf_conntrack_lock); |
| list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list, |
| list) { |
| if (del_timer(&exp->timeout)) { |
| nf_ct_unlink_expect(exp); |
| nf_conntrack_expect_put(exp); |
| } |
| } |
| write_unlock_bh(&nf_conntrack_lock); |
| } |
| |
| return 0; |
| } |
| static int |
| ctnetlink_change_expect(struct nf_conntrack_expect *x, struct nfattr *cda[]) |
| { |
| return -EOPNOTSUPP; |
| } |
| |
| static int |
| ctnetlink_create_expect(struct nfattr *cda[], u_int8_t u3) |
| { |
| struct nf_conntrack_tuple tuple, mask, master_tuple; |
| struct nf_conntrack_tuple_hash *h = NULL; |
| struct nf_conntrack_expect *exp; |
| struct nf_conn *ct; |
| struct nf_conn_help *help; |
| int err = 0; |
| |
| DEBUGP("entered %s\n", __FUNCTION__); |
| |
| /* caller guarantees that those three CTA_EXPECT_* exist */ |
| err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3); |
| if (err < 0) |
| return err; |
| err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3); |
| if (err < 0) |
| return err; |
| err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3); |
| if (err < 0) |
| return err; |
| |
| /* Look for master conntrack of this expectation */ |
| h = nf_conntrack_find_get(&master_tuple, NULL); |
| if (!h) |
| return -ENOENT; |
| ct = nf_ct_tuplehash_to_ctrack(h); |
| help = nfct_help(ct); |
| |
| if (!help || !help->helper) { |
| /* such conntrack hasn't got any helper, abort */ |
| err = -EINVAL; |
| goto out; |
| } |
| |
| exp = nf_conntrack_expect_alloc(ct); |
| if (!exp) { |
| err = -ENOMEM; |
| goto out; |
| } |
| |
| exp->expectfn = NULL; |
| exp->flags = 0; |
| exp->master = ct; |
| memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple)); |
| memcpy(&exp->mask, &mask, sizeof(struct nf_conntrack_tuple)); |
| |
| err = nf_conntrack_expect_related(exp); |
| nf_conntrack_expect_put(exp); |
| |
| out: |
| nf_ct_put(nf_ct_tuplehash_to_ctrack(h)); |
| return err; |
| } |
| |
| static int |
| ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb, |
| struct nlmsghdr *nlh, struct nfattr *cda[], int *errp) |
| { |
| struct nf_conntrack_tuple tuple; |
| struct nf_conntrack_expect *exp; |
| struct nfgenmsg *nfmsg = NLMSG_DATA(nlh); |
| u_int8_t u3 = nfmsg->nfgen_family; |
| int err = 0; |
| |
| DEBUGP("entered %s\n", __FUNCTION__); |
| |
| if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp)) |
| return -EINVAL; |
| |
| if (!cda[CTA_EXPECT_TUPLE-1] |
| || !cda[CTA_EXPECT_MASK-1] |
| || !cda[CTA_EXPECT_MASTER-1]) |
| return -EINVAL; |
| |
| err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3); |
| if (err < 0) |
| return err; |
| |
| write_lock_bh(&nf_conntrack_lock); |
| exp = __nf_conntrack_expect_find(&tuple); |
| |
| if (!exp) { |
| write_unlock_bh(&nf_conntrack_lock); |
| err = -ENOENT; |
| if (nlh->nlmsg_flags & NLM_F_CREATE) |
| err = ctnetlink_create_expect(cda, u3); |
| return err; |
| } |
| |
| err = -EEXIST; |
| if (!(nlh->nlmsg_flags & NLM_F_EXCL)) |
| err = ctnetlink_change_expect(exp, cda); |
| write_unlock_bh(&nf_conntrack_lock); |
| |
| DEBUGP("leaving\n"); |
| |
| 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 struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = { |
| [IPCTNL_MSG_CT_NEW] = { .call = ctnetlink_new_conntrack, |
| .attr_count = CTA_MAX, }, |
| [IPCTNL_MSG_CT_GET] = { .call = ctnetlink_get_conntrack, |
| .attr_count = CTA_MAX, }, |
| [IPCTNL_MSG_CT_DELETE] = { .call = ctnetlink_del_conntrack, |
| .attr_count = CTA_MAX, }, |
| [IPCTNL_MSG_CT_GET_CTRZERO] = { .call = ctnetlink_get_conntrack, |
| .attr_count = CTA_MAX, }, |
| }; |
| |
| static struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = { |
| [IPCTNL_MSG_EXP_GET] = { .call = ctnetlink_get_expect, |
| .attr_count = CTA_EXPECT_MAX, }, |
| [IPCTNL_MSG_EXP_NEW] = { .call = ctnetlink_new_expect, |
| .attr_count = CTA_EXPECT_MAX, }, |
| [IPCTNL_MSG_EXP_DELETE] = { .call = ctnetlink_del_expect, |
| .attr_count = CTA_EXPECT_MAX, }, |
| }; |
| |
| static struct nfnetlink_subsystem ctnl_subsys = { |
| .name = "conntrack", |
| .subsys_id = NFNL_SUBSYS_CTNETLINK, |
| .cb_count = IPCTNL_MSG_MAX, |
| .cb = ctnl_cb, |
| }; |
| |
| static struct nfnetlink_subsystem ctnl_exp_subsys = { |
| .name = "conntrack_expect", |
| .subsys_id = NFNL_SUBSYS_CTNETLINK_EXP, |
| .cb_count = IPCTNL_MSG_EXP_MAX, |
| .cb = ctnl_exp_cb, |
| }; |
| |
| MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK); |
| MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP); |
| |
| static int __init ctnetlink_init(void) |
| { |
| int ret; |
| |
| printk("ctnetlink v%s: registering with nfnetlink.\n", version); |
| ret = nfnetlink_subsys_register(&ctnl_subsys); |
| if (ret < 0) { |
| printk("ctnetlink_init: cannot register with nfnetlink.\n"); |
| goto err_out; |
| } |
| |
| ret = nfnetlink_subsys_register(&ctnl_exp_subsys); |
| if (ret < 0) { |
| printk("ctnetlink_init: cannot register exp with nfnetlink.\n"); |
| goto err_unreg_subsys; |
| } |
| |
| #ifdef CONFIG_NF_CONNTRACK_EVENTS |
| ret = nf_conntrack_register_notifier(&ctnl_notifier); |
| if (ret < 0) { |
| printk("ctnetlink_init: cannot register notifier.\n"); |
| goto err_unreg_exp_subsys; |
| } |
| |
| ret = nf_conntrack_expect_register_notifier(&ctnl_notifier_exp); |
| if (ret < 0) { |
| printk("ctnetlink_init: cannot expect register notifier.\n"); |
| goto err_unreg_notifier; |
| } |
| #endif |
| |
| return 0; |
| |
| #ifdef CONFIG_NF_CONNTRACK_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_conntrack_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); |