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