| /* |
| * Copyright (c) 2015 Nicira, Inc. |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of version 2 of the GNU General Public |
| * License as published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, but |
| * WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * General Public License for more details. |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/openvswitch.h> |
| #include <linux/tcp.h> |
| #include <linux/udp.h> |
| #include <linux/sctp.h> |
| #include <net/ip.h> |
| #include <net/netfilter/nf_conntrack_core.h> |
| #include <net/netfilter/nf_conntrack_helper.h> |
| #include <net/netfilter/nf_conntrack_labels.h> |
| #include <net/netfilter/nf_conntrack_seqadj.h> |
| #include <net/netfilter/nf_conntrack_zones.h> |
| #include <net/netfilter/ipv6/nf_defrag_ipv6.h> |
| #include <net/ipv6_frag.h> |
| |
| #ifdef CONFIG_NF_NAT_NEEDED |
| #include <linux/netfilter/nf_nat.h> |
| #include <net/netfilter/nf_nat_core.h> |
| #include <net/netfilter/nf_nat_l3proto.h> |
| #endif |
| |
| #include "datapath.h" |
| #include "conntrack.h" |
| #include "flow.h" |
| #include "flow_netlink.h" |
| |
| struct ovs_ct_len_tbl { |
| int maxlen; |
| int minlen; |
| }; |
| |
| /* Metadata mark for masked write to conntrack mark */ |
| struct md_mark { |
| u32 value; |
| u32 mask; |
| }; |
| |
| /* Metadata label for masked write to conntrack label. */ |
| struct md_labels { |
| struct ovs_key_ct_labels value; |
| struct ovs_key_ct_labels mask; |
| }; |
| |
| enum ovs_ct_nat { |
| OVS_CT_NAT = 1 << 0, /* NAT for committed connections only. */ |
| OVS_CT_SRC_NAT = 1 << 1, /* Source NAT for NEW connections. */ |
| OVS_CT_DST_NAT = 1 << 2, /* Destination NAT for NEW connections. */ |
| }; |
| |
| /* Conntrack action context for execution. */ |
| struct ovs_conntrack_info { |
| struct nf_conntrack_helper *helper; |
| struct nf_conntrack_zone zone; |
| struct nf_conn *ct; |
| u8 commit : 1; |
| u8 nat : 3; /* enum ovs_ct_nat */ |
| u8 force : 1; |
| u8 have_eventmask : 1; |
| u16 family; |
| u32 eventmask; /* Mask of 1 << IPCT_*. */ |
| struct md_mark mark; |
| struct md_labels labels; |
| #ifdef CONFIG_NF_NAT_NEEDED |
| struct nf_nat_range range; /* Only present for SRC NAT and DST NAT. */ |
| #endif |
| }; |
| |
| static bool labels_nonzero(const struct ovs_key_ct_labels *labels); |
| |
| static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info); |
| |
| static u16 key_to_nfproto(const struct sw_flow_key *key) |
| { |
| switch (ntohs(key->eth.type)) { |
| case ETH_P_IP: |
| return NFPROTO_IPV4; |
| case ETH_P_IPV6: |
| return NFPROTO_IPV6; |
| default: |
| return NFPROTO_UNSPEC; |
| } |
| } |
| |
| /* Map SKB connection state into the values used by flow definition. */ |
| static u8 ovs_ct_get_state(enum ip_conntrack_info ctinfo) |
| { |
| u8 ct_state = OVS_CS_F_TRACKED; |
| |
| switch (ctinfo) { |
| case IP_CT_ESTABLISHED_REPLY: |
| case IP_CT_RELATED_REPLY: |
| ct_state |= OVS_CS_F_REPLY_DIR; |
| break; |
| default: |
| break; |
| } |
| |
| switch (ctinfo) { |
| case IP_CT_ESTABLISHED: |
| case IP_CT_ESTABLISHED_REPLY: |
| ct_state |= OVS_CS_F_ESTABLISHED; |
| break; |
| case IP_CT_RELATED: |
| case IP_CT_RELATED_REPLY: |
| ct_state |= OVS_CS_F_RELATED; |
| break; |
| case IP_CT_NEW: |
| ct_state |= OVS_CS_F_NEW; |
| break; |
| default: |
| break; |
| } |
| |
| return ct_state; |
| } |
| |
| static u32 ovs_ct_get_mark(const struct nf_conn *ct) |
| { |
| #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) |
| return ct ? ct->mark : 0; |
| #else |
| return 0; |
| #endif |
| } |
| |
| /* Guard against conntrack labels max size shrinking below 128 bits. */ |
| #if NF_CT_LABELS_MAX_SIZE < 16 |
| #error NF_CT_LABELS_MAX_SIZE must be at least 16 bytes |
| #endif |
| |
| static void ovs_ct_get_labels(const struct nf_conn *ct, |
| struct ovs_key_ct_labels *labels) |
| { |
| struct nf_conn_labels *cl = ct ? nf_ct_labels_find(ct) : NULL; |
| |
| if (cl) |
| memcpy(labels, cl->bits, OVS_CT_LABELS_LEN); |
| else |
| memset(labels, 0, OVS_CT_LABELS_LEN); |
| } |
| |
| static void __ovs_ct_update_key_orig_tp(struct sw_flow_key *key, |
| const struct nf_conntrack_tuple *orig, |
| u8 icmp_proto) |
| { |
| key->ct_orig_proto = orig->dst.protonum; |
| if (orig->dst.protonum == icmp_proto) { |
| key->ct.orig_tp.src = htons(orig->dst.u.icmp.type); |
| key->ct.orig_tp.dst = htons(orig->dst.u.icmp.code); |
| } else { |
| key->ct.orig_tp.src = orig->src.u.all; |
| key->ct.orig_tp.dst = orig->dst.u.all; |
| } |
| } |
| |
| static void __ovs_ct_update_key(struct sw_flow_key *key, u8 state, |
| const struct nf_conntrack_zone *zone, |
| const struct nf_conn *ct) |
| { |
| key->ct_state = state; |
| key->ct_zone = zone->id; |
| key->ct.mark = ovs_ct_get_mark(ct); |
| ovs_ct_get_labels(ct, &key->ct.labels); |
| |
| if (ct) { |
| const struct nf_conntrack_tuple *orig; |
| |
| /* Use the master if we have one. */ |
| if (ct->master) |
| ct = ct->master; |
| orig = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple; |
| |
| /* IP version must match with the master connection. */ |
| if (key->eth.type == htons(ETH_P_IP) && |
| nf_ct_l3num(ct) == NFPROTO_IPV4) { |
| key->ipv4.ct_orig.src = orig->src.u3.ip; |
| key->ipv4.ct_orig.dst = orig->dst.u3.ip; |
| __ovs_ct_update_key_orig_tp(key, orig, IPPROTO_ICMP); |
| return; |
| } else if (key->eth.type == htons(ETH_P_IPV6) && |
| !sw_flow_key_is_nd(key) && |
| nf_ct_l3num(ct) == NFPROTO_IPV6) { |
| key->ipv6.ct_orig.src = orig->src.u3.in6; |
| key->ipv6.ct_orig.dst = orig->dst.u3.in6; |
| __ovs_ct_update_key_orig_tp(key, orig, NEXTHDR_ICMP); |
| return; |
| } |
| } |
| /* Clear 'ct_orig_proto' to mark the non-existence of conntrack |
| * original direction key fields. |
| */ |
| key->ct_orig_proto = 0; |
| } |
| |
| /* Update 'key' based on skb->_nfct. If 'post_ct' is true, then OVS has |
| * previously sent the packet to conntrack via the ct action. If |
| * 'keep_nat_flags' is true, the existing NAT flags retained, else they are |
| * initialized from the connection status. |
| */ |
| static void ovs_ct_update_key(const struct sk_buff *skb, |
| const struct ovs_conntrack_info *info, |
| struct sw_flow_key *key, bool post_ct, |
| bool keep_nat_flags) |
| { |
| const struct nf_conntrack_zone *zone = &nf_ct_zone_dflt; |
| enum ip_conntrack_info ctinfo; |
| struct nf_conn *ct; |
| u8 state = 0; |
| |
| ct = nf_ct_get(skb, &ctinfo); |
| if (ct) { |
| state = ovs_ct_get_state(ctinfo); |
| /* All unconfirmed entries are NEW connections. */ |
| if (!nf_ct_is_confirmed(ct)) |
| state |= OVS_CS_F_NEW; |
| /* OVS persists the related flag for the duration of the |
| * connection. |
| */ |
| if (ct->master) |
| state |= OVS_CS_F_RELATED; |
| if (keep_nat_flags) { |
| state |= key->ct_state & OVS_CS_F_NAT_MASK; |
| } else { |
| if (ct->status & IPS_SRC_NAT) |
| state |= OVS_CS_F_SRC_NAT; |
| if (ct->status & IPS_DST_NAT) |
| state |= OVS_CS_F_DST_NAT; |
| } |
| zone = nf_ct_zone(ct); |
| } else if (post_ct) { |
| state = OVS_CS_F_TRACKED | OVS_CS_F_INVALID; |
| if (info) |
| zone = &info->zone; |
| } |
| __ovs_ct_update_key(key, state, zone, ct); |
| } |
| |
| /* This is called to initialize CT key fields possibly coming in from the local |
| * stack. |
| */ |
| void ovs_ct_fill_key(const struct sk_buff *skb, struct sw_flow_key *key) |
| { |
| ovs_ct_update_key(skb, NULL, key, false, false); |
| } |
| |
| int ovs_ct_put_key(const struct sw_flow_key *swkey, |
| const struct sw_flow_key *output, struct sk_buff *skb) |
| { |
| if (nla_put_u32(skb, OVS_KEY_ATTR_CT_STATE, output->ct_state)) |
| return -EMSGSIZE; |
| |
| if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && |
| nla_put_u16(skb, OVS_KEY_ATTR_CT_ZONE, output->ct_zone)) |
| return -EMSGSIZE; |
| |
| if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && |
| nla_put_u32(skb, OVS_KEY_ATTR_CT_MARK, output->ct.mark)) |
| return -EMSGSIZE; |
| |
| if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && |
| nla_put(skb, OVS_KEY_ATTR_CT_LABELS, sizeof(output->ct.labels), |
| &output->ct.labels)) |
| return -EMSGSIZE; |
| |
| if (swkey->ct_orig_proto) { |
| if (swkey->eth.type == htons(ETH_P_IP)) { |
| struct ovs_key_ct_tuple_ipv4 orig; |
| |
| memset(&orig, 0, sizeof(orig)); |
| orig.ipv4_src = output->ipv4.ct_orig.src; |
| orig.ipv4_dst = output->ipv4.ct_orig.dst; |
| orig.src_port = output->ct.orig_tp.src; |
| orig.dst_port = output->ct.orig_tp.dst; |
| orig.ipv4_proto = output->ct_orig_proto; |
| |
| if (nla_put(skb, OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4, |
| sizeof(orig), &orig)) |
| return -EMSGSIZE; |
| } else if (swkey->eth.type == htons(ETH_P_IPV6)) { |
| struct ovs_key_ct_tuple_ipv6 orig; |
| |
| memset(&orig, 0, sizeof(orig)); |
| memcpy(orig.ipv6_src, output->ipv6.ct_orig.src.s6_addr32, |
| sizeof(orig.ipv6_src)); |
| memcpy(orig.ipv6_dst, output->ipv6.ct_orig.dst.s6_addr32, |
| sizeof(orig.ipv6_dst)); |
| orig.src_port = output->ct.orig_tp.src; |
| orig.dst_port = output->ct.orig_tp.dst; |
| orig.ipv6_proto = output->ct_orig_proto; |
| |
| if (nla_put(skb, OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6, |
| sizeof(orig), &orig)) |
| return -EMSGSIZE; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int ovs_ct_set_mark(struct nf_conn *ct, struct sw_flow_key *key, |
| u32 ct_mark, u32 mask) |
| { |
| #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) |
| u32 new_mark; |
| |
| new_mark = ct_mark | (ct->mark & ~(mask)); |
| if (ct->mark != new_mark) { |
| ct->mark = new_mark; |
| if (nf_ct_is_confirmed(ct)) |
| nf_conntrack_event_cache(IPCT_MARK, ct); |
| key->ct.mark = new_mark; |
| } |
| |
| return 0; |
| #else |
| return -ENOTSUPP; |
| #endif |
| } |
| |
| static struct nf_conn_labels *ovs_ct_get_conn_labels(struct nf_conn *ct) |
| { |
| struct nf_conn_labels *cl; |
| |
| cl = nf_ct_labels_find(ct); |
| if (!cl) { |
| nf_ct_labels_ext_add(ct); |
| cl = nf_ct_labels_find(ct); |
| } |
| |
| return cl; |
| } |
| |
| /* Initialize labels for a new, yet to be committed conntrack entry. Note that |
| * since the new connection is not yet confirmed, and thus no-one else has |
| * access to it's labels, we simply write them over. |
| */ |
| static int ovs_ct_init_labels(struct nf_conn *ct, struct sw_flow_key *key, |
| const struct ovs_key_ct_labels *labels, |
| const struct ovs_key_ct_labels *mask) |
| { |
| struct nf_conn_labels *cl, *master_cl; |
| bool have_mask = labels_nonzero(mask); |
| |
| /* Inherit master's labels to the related connection? */ |
| master_cl = ct->master ? nf_ct_labels_find(ct->master) : NULL; |
| |
| if (!master_cl && !have_mask) |
| return 0; /* Nothing to do. */ |
| |
| cl = ovs_ct_get_conn_labels(ct); |
| if (!cl) |
| return -ENOSPC; |
| |
| /* Inherit the master's labels, if any. */ |
| if (master_cl) |
| *cl = *master_cl; |
| |
| if (have_mask) { |
| u32 *dst = (u32 *)cl->bits; |
| int i; |
| |
| for (i = 0; i < OVS_CT_LABELS_LEN_32; i++) |
| dst[i] = (dst[i] & ~mask->ct_labels_32[i]) | |
| (labels->ct_labels_32[i] |
| & mask->ct_labels_32[i]); |
| } |
| |
| /* Labels are included in the IPCTNL_MSG_CT_NEW event only if the |
| * IPCT_LABEL bit is set in the event cache. |
| */ |
| nf_conntrack_event_cache(IPCT_LABEL, ct); |
| |
| memcpy(&key->ct.labels, cl->bits, OVS_CT_LABELS_LEN); |
| |
| return 0; |
| } |
| |
| static int ovs_ct_set_labels(struct nf_conn *ct, struct sw_flow_key *key, |
| const struct ovs_key_ct_labels *labels, |
| const struct ovs_key_ct_labels *mask) |
| { |
| struct nf_conn_labels *cl; |
| int err; |
| |
| cl = ovs_ct_get_conn_labels(ct); |
| if (!cl) |
| return -ENOSPC; |
| |
| err = nf_connlabels_replace(ct, labels->ct_labels_32, |
| mask->ct_labels_32, |
| OVS_CT_LABELS_LEN_32); |
| if (err) |
| return err; |
| |
| memcpy(&key->ct.labels, cl->bits, OVS_CT_LABELS_LEN); |
| |
| return 0; |
| } |
| |
| /* 'skb' should already be pulled to nh_ofs. */ |
| static int ovs_ct_helper(struct sk_buff *skb, u16 proto) |
| { |
| const struct nf_conntrack_helper *helper; |
| const struct nf_conn_help *help; |
| enum ip_conntrack_info ctinfo; |
| unsigned int protoff; |
| struct nf_conn *ct; |
| int err; |
| |
| ct = nf_ct_get(skb, &ctinfo); |
| if (!ct || ctinfo == IP_CT_RELATED_REPLY) |
| return NF_ACCEPT; |
| |
| help = nfct_help(ct); |
| if (!help) |
| return NF_ACCEPT; |
| |
| helper = rcu_dereference(help->helper); |
| if (!helper) |
| return NF_ACCEPT; |
| |
| switch (proto) { |
| case NFPROTO_IPV4: |
| protoff = ip_hdrlen(skb); |
| break; |
| case NFPROTO_IPV6: { |
| u8 nexthdr = ipv6_hdr(skb)->nexthdr; |
| __be16 frag_off; |
| int ofs; |
| |
| ofs = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr, |
| &frag_off); |
| if (ofs < 0 || (frag_off & htons(~0x7)) != 0) { |
| pr_debug("proto header not found\n"); |
| return NF_ACCEPT; |
| } |
| protoff = ofs; |
| break; |
| } |
| default: |
| WARN_ONCE(1, "helper invoked on non-IP family!"); |
| return NF_DROP; |
| } |
| |
| err = helper->help(skb, protoff, ct, ctinfo); |
| if (err != NF_ACCEPT) |
| return err; |
| |
| /* Adjust seqs after helper. This is needed due to some helpers (e.g., |
| * FTP with NAT) adusting the TCP payload size when mangling IP |
| * addresses and/or port numbers in the text-based control connection. |
| */ |
| if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) && |
| !nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) |
| return NF_DROP; |
| return NF_ACCEPT; |
| } |
| |
| /* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero |
| * value if 'skb' is freed. |
| */ |
| static int handle_fragments(struct net *net, struct sw_flow_key *key, |
| u16 zone, struct sk_buff *skb) |
| { |
| struct ovs_skb_cb ovs_cb = *OVS_CB(skb); |
| int err; |
| |
| if (key->eth.type == htons(ETH_P_IP)) { |
| enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone; |
| |
| memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); |
| err = ip_defrag(net, skb, user); |
| if (err) |
| return err; |
| |
| ovs_cb.mru = IPCB(skb)->frag_max_size; |
| #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) |
| } else if (key->eth.type == htons(ETH_P_IPV6)) { |
| enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone; |
| |
| memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm)); |
| err = nf_ct_frag6_gather(net, skb, user); |
| if (err) { |
| if (err != -EINPROGRESS) |
| kfree_skb(skb); |
| return err; |
| } |
| |
| key->ip.proto = ipv6_hdr(skb)->nexthdr; |
| ovs_cb.mru = IP6CB(skb)->frag_max_size; |
| #endif |
| } else { |
| kfree_skb(skb); |
| return -EPFNOSUPPORT; |
| } |
| |
| key->ip.frag = OVS_FRAG_TYPE_NONE; |
| skb_clear_hash(skb); |
| skb->ignore_df = 1; |
| *OVS_CB(skb) = ovs_cb; |
| |
| return 0; |
| } |
| |
| static struct nf_conntrack_expect * |
| ovs_ct_expect_find(struct net *net, const struct nf_conntrack_zone *zone, |
| u16 proto, const struct sk_buff *skb) |
| { |
| struct nf_conntrack_tuple tuple; |
| struct nf_conntrack_expect *exp; |
| |
| if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb), proto, net, &tuple)) |
| return NULL; |
| |
| exp = __nf_ct_expect_find(net, zone, &tuple); |
| if (exp) { |
| struct nf_conntrack_tuple_hash *h; |
| |
| /* Delete existing conntrack entry, if it clashes with the |
| * expectation. This can happen since conntrack ALGs do not |
| * check for clashes between (new) expectations and existing |
| * conntrack entries. nf_conntrack_in() will check the |
| * expectations only if a conntrack entry can not be found, |
| * which can lead to OVS finding the expectation (here) in the |
| * init direction, but which will not be removed by the |
| * nf_conntrack_in() call, if a matching conntrack entry is |
| * found instead. In this case all init direction packets |
| * would be reported as new related packets, while reply |
| * direction packets would be reported as un-related |
| * established packets. |
| */ |
| h = nf_conntrack_find_get(net, zone, &tuple); |
| if (h) { |
| struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h); |
| |
| nf_ct_delete(ct, 0, 0); |
| nf_conntrack_put(&ct->ct_general); |
| } |
| } |
| |
| return exp; |
| } |
| |
| /* This replicates logic from nf_conntrack_core.c that is not exported. */ |
| static enum ip_conntrack_info |
| ovs_ct_get_info(const struct nf_conntrack_tuple_hash *h) |
| { |
| const struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h); |
| |
| if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY) |
| return IP_CT_ESTABLISHED_REPLY; |
| /* Once we've had two way comms, always ESTABLISHED. */ |
| if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) |
| return IP_CT_ESTABLISHED; |
| if (test_bit(IPS_EXPECTED_BIT, &ct->status)) |
| return IP_CT_RELATED; |
| return IP_CT_NEW; |
| } |
| |
| /* Find an existing connection which this packet belongs to without |
| * re-attributing statistics or modifying the connection state. This allows an |
| * skb->_nfct lost due to an upcall to be recovered during actions execution. |
| * |
| * Must be called with rcu_read_lock. |
| * |
| * On success, populates skb->_nfct and returns the connection. Returns NULL |
| * if there is no existing entry. |
| */ |
| static struct nf_conn * |
| ovs_ct_find_existing(struct net *net, const struct nf_conntrack_zone *zone, |
| u8 l3num, struct sk_buff *skb, bool natted) |
| { |
| const struct nf_conntrack_l3proto *l3proto; |
| const struct nf_conntrack_l4proto *l4proto; |
| struct nf_conntrack_tuple tuple; |
| struct nf_conntrack_tuple_hash *h; |
| struct nf_conn *ct; |
| unsigned int dataoff; |
| u8 protonum; |
| |
| l3proto = __nf_ct_l3proto_find(l3num); |
| if (l3proto->get_l4proto(skb, skb_network_offset(skb), &dataoff, |
| &protonum) <= 0) { |
| pr_debug("ovs_ct_find_existing: Can't get protonum\n"); |
| return NULL; |
| } |
| l4proto = __nf_ct_l4proto_find(l3num, protonum); |
| if (!nf_ct_get_tuple(skb, skb_network_offset(skb), dataoff, l3num, |
| protonum, net, &tuple, l3proto, l4proto)) { |
| pr_debug("ovs_ct_find_existing: Can't get tuple\n"); |
| return NULL; |
| } |
| |
| /* Must invert the tuple if skb has been transformed by NAT. */ |
| if (natted) { |
| struct nf_conntrack_tuple inverse; |
| |
| if (!nf_ct_invert_tuple(&inverse, &tuple, l3proto, l4proto)) { |
| pr_debug("ovs_ct_find_existing: Inversion failed!\n"); |
| return NULL; |
| } |
| tuple = inverse; |
| } |
| |
| /* look for tuple match */ |
| h = nf_conntrack_find_get(net, zone, &tuple); |
| if (!h) |
| return NULL; /* Not found. */ |
| |
| ct = nf_ct_tuplehash_to_ctrack(h); |
| |
| /* Inverted packet tuple matches the reverse direction conntrack tuple, |
| * select the other tuplehash to get the right 'ctinfo' bits for this |
| * packet. |
| */ |
| if (natted) |
| h = &ct->tuplehash[!h->tuple.dst.dir]; |
| |
| nf_ct_set(skb, ct, ovs_ct_get_info(h)); |
| return ct; |
| } |
| |
| static |
| struct nf_conn *ovs_ct_executed(struct net *net, |
| const struct sw_flow_key *key, |
| const struct ovs_conntrack_info *info, |
| struct sk_buff *skb, |
| bool *ct_executed) |
| { |
| struct nf_conn *ct = NULL; |
| |
| /* If no ct, check if we have evidence that an existing conntrack entry |
| * might be found for this skb. This happens when we lose a skb->_nfct |
| * due to an upcall, or if the direction is being forced. If the |
| * connection was not confirmed, it is not cached and needs to be run |
| * through conntrack again. |
| */ |
| *ct_executed = (key->ct_state & OVS_CS_F_TRACKED) && |
| !(key->ct_state & OVS_CS_F_INVALID) && |
| (key->ct_zone == info->zone.id); |
| |
| if (*ct_executed || (!key->ct_state && info->force)) { |
| ct = ovs_ct_find_existing(net, &info->zone, info->family, skb, |
| !!(key->ct_state & |
| OVS_CS_F_NAT_MASK)); |
| } |
| |
| return ct; |
| } |
| |
| /* Determine whether skb->_nfct is equal to the result of conntrack lookup. */ |
| static bool skb_nfct_cached(struct net *net, |
| const struct sw_flow_key *key, |
| const struct ovs_conntrack_info *info, |
| struct sk_buff *skb) |
| { |
| enum ip_conntrack_info ctinfo; |
| struct nf_conn *ct; |
| bool ct_executed = true; |
| |
| ct = nf_ct_get(skb, &ctinfo); |
| if (!ct) |
| ct = ovs_ct_executed(net, key, info, skb, &ct_executed); |
| |
| if (ct) |
| nf_ct_get(skb, &ctinfo); |
| else |
| return false; |
| |
| if (!net_eq(net, read_pnet(&ct->ct_net))) |
| return false; |
| if (!nf_ct_zone_equal_any(info->ct, nf_ct_zone(ct))) |
| return false; |
| if (info->helper) { |
| struct nf_conn_help *help; |
| |
| help = nf_ct_ext_find(ct, NF_CT_EXT_HELPER); |
| if (help && rcu_access_pointer(help->helper) != info->helper) |
| return false; |
| } |
| /* Force conntrack entry direction to the current packet? */ |
| if (info->force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) { |
| /* Delete the conntrack entry if confirmed, else just release |
| * the reference. |
| */ |
| if (nf_ct_is_confirmed(ct)) |
| nf_ct_delete(ct, 0, 0); |
| |
| nf_conntrack_put(&ct->ct_general); |
| nf_ct_set(skb, NULL, 0); |
| return false; |
| } |
| |
| return ct_executed; |
| } |
| |
| #ifdef CONFIG_NF_NAT_NEEDED |
| /* Modelled after nf_nat_ipv[46]_fn(). |
| * range is only used for new, uninitialized NAT state. |
| * Returns either NF_ACCEPT or NF_DROP. |
| */ |
| static int ovs_ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct, |
| enum ip_conntrack_info ctinfo, |
| const struct nf_nat_range *range, |
| enum nf_nat_manip_type maniptype) |
| { |
| int hooknum, nh_off, err = NF_ACCEPT; |
| |
| nh_off = skb_network_offset(skb); |
| skb_pull_rcsum(skb, nh_off); |
| |
| /* See HOOK2MANIP(). */ |
| if (maniptype == NF_NAT_MANIP_SRC) |
| hooknum = NF_INET_LOCAL_IN; /* Source NAT */ |
| else |
| hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */ |
| |
| switch (ctinfo) { |
| case IP_CT_RELATED: |
| case IP_CT_RELATED_REPLY: |
| if (IS_ENABLED(CONFIG_NF_NAT_IPV4) && |
| skb->protocol == htons(ETH_P_IP) && |
| ip_hdr(skb)->protocol == IPPROTO_ICMP) { |
| if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo, |
| hooknum)) |
| err = NF_DROP; |
| goto push; |
| } else if (IS_ENABLED(CONFIG_NF_NAT_IPV6) && |
| skb->protocol == htons(ETH_P_IPV6)) { |
| __be16 frag_off; |
| u8 nexthdr = ipv6_hdr(skb)->nexthdr; |
| int hdrlen = ipv6_skip_exthdr(skb, |
| sizeof(struct ipv6hdr), |
| &nexthdr, &frag_off); |
| |
| if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) { |
| if (!nf_nat_icmpv6_reply_translation(skb, ct, |
| ctinfo, |
| hooknum, |
| hdrlen)) |
| err = NF_DROP; |
| goto push; |
| } |
| } |
| /* Non-ICMP, fall thru to initialize if needed. */ |
| case IP_CT_NEW: |
| /* Seen it before? This can happen for loopback, retrans, |
| * or local packets. |
| */ |
| if (!nf_nat_initialized(ct, maniptype)) { |
| /* Initialize according to the NAT action. */ |
| err = (range && range->flags & NF_NAT_RANGE_MAP_IPS) |
| /* Action is set up to establish a new |
| * mapping. |
| */ |
| ? nf_nat_setup_info(ct, range, maniptype) |
| : nf_nat_alloc_null_binding(ct, hooknum); |
| if (err != NF_ACCEPT) |
| goto push; |
| } |
| break; |
| |
| case IP_CT_ESTABLISHED: |
| case IP_CT_ESTABLISHED_REPLY: |
| break; |
| |
| default: |
| err = NF_DROP; |
| goto push; |
| } |
| |
| err = nf_nat_packet(ct, ctinfo, hooknum, skb); |
| push: |
| skb_push(skb, nh_off); |
| skb_postpush_rcsum(skb, skb->data, nh_off); |
| |
| return err; |
| } |
| |
| static void ovs_nat_update_key(struct sw_flow_key *key, |
| const struct sk_buff *skb, |
| enum nf_nat_manip_type maniptype) |
| { |
| if (maniptype == NF_NAT_MANIP_SRC) { |
| __be16 src; |
| |
| key->ct_state |= OVS_CS_F_SRC_NAT; |
| if (key->eth.type == htons(ETH_P_IP)) |
| key->ipv4.addr.src = ip_hdr(skb)->saddr; |
| else if (key->eth.type == htons(ETH_P_IPV6)) |
| memcpy(&key->ipv6.addr.src, &ipv6_hdr(skb)->saddr, |
| sizeof(key->ipv6.addr.src)); |
| else |
| return; |
| |
| if (key->ip.proto == IPPROTO_UDP) |
| src = udp_hdr(skb)->source; |
| else if (key->ip.proto == IPPROTO_TCP) |
| src = tcp_hdr(skb)->source; |
| else if (key->ip.proto == IPPROTO_SCTP) |
| src = sctp_hdr(skb)->source; |
| else |
| return; |
| |
| key->tp.src = src; |
| } else { |
| __be16 dst; |
| |
| key->ct_state |= OVS_CS_F_DST_NAT; |
| if (key->eth.type == htons(ETH_P_IP)) |
| key->ipv4.addr.dst = ip_hdr(skb)->daddr; |
| else if (key->eth.type == htons(ETH_P_IPV6)) |
| memcpy(&key->ipv6.addr.dst, &ipv6_hdr(skb)->daddr, |
| sizeof(key->ipv6.addr.dst)); |
| else |
| return; |
| |
| if (key->ip.proto == IPPROTO_UDP) |
| dst = udp_hdr(skb)->dest; |
| else if (key->ip.proto == IPPROTO_TCP) |
| dst = tcp_hdr(skb)->dest; |
| else if (key->ip.proto == IPPROTO_SCTP) |
| dst = sctp_hdr(skb)->dest; |
| else |
| return; |
| |
| key->tp.dst = dst; |
| } |
| } |
| |
| /* Returns NF_DROP if the packet should be dropped, NF_ACCEPT otherwise. */ |
| static int ovs_ct_nat(struct net *net, struct sw_flow_key *key, |
| const struct ovs_conntrack_info *info, |
| struct sk_buff *skb, struct nf_conn *ct, |
| enum ip_conntrack_info ctinfo) |
| { |
| enum nf_nat_manip_type maniptype; |
| int err; |
| |
| /* Add NAT extension if not confirmed yet. */ |
| if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct)) |
| return NF_ACCEPT; /* Can't NAT. */ |
| |
| /* Determine NAT type. |
| * Check if the NAT type can be deduced from the tracked connection. |
| * Make sure new expected connections (IP_CT_RELATED) are NATted only |
| * when committing. |
| */ |
| if (info->nat & OVS_CT_NAT && ctinfo != IP_CT_NEW && |
| ct->status & IPS_NAT_MASK && |
| (ctinfo != IP_CT_RELATED || info->commit)) { |
| /* NAT an established or related connection like before. */ |
| if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY) |
| /* This is the REPLY direction for a connection |
| * for which NAT was applied in the forward |
| * direction. Do the reverse NAT. |
| */ |
| maniptype = ct->status & IPS_SRC_NAT |
| ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC; |
| else |
| maniptype = ct->status & IPS_SRC_NAT |
| ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST; |
| } else if (info->nat & OVS_CT_SRC_NAT) { |
| maniptype = NF_NAT_MANIP_SRC; |
| } else if (info->nat & OVS_CT_DST_NAT) { |
| maniptype = NF_NAT_MANIP_DST; |
| } else { |
| return NF_ACCEPT; /* Connection is not NATed. */ |
| } |
| err = ovs_ct_nat_execute(skb, ct, ctinfo, &info->range, maniptype); |
| |
| if (err == NF_ACCEPT && ct->status & IPS_DST_NAT) { |
| if (ct->status & IPS_SRC_NAT) { |
| if (maniptype == NF_NAT_MANIP_SRC) |
| maniptype = NF_NAT_MANIP_DST; |
| else |
| maniptype = NF_NAT_MANIP_SRC; |
| |
| err = ovs_ct_nat_execute(skb, ct, ctinfo, &info->range, |
| maniptype); |
| } else if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) { |
| err = ovs_ct_nat_execute(skb, ct, ctinfo, NULL, |
| NF_NAT_MANIP_SRC); |
| } |
| } |
| |
| /* Mark NAT done if successful and update the flow key. */ |
| if (err == NF_ACCEPT) |
| ovs_nat_update_key(key, skb, maniptype); |
| |
| return err; |
| } |
| #else /* !CONFIG_NF_NAT_NEEDED */ |
| static int ovs_ct_nat(struct net *net, struct sw_flow_key *key, |
| const struct ovs_conntrack_info *info, |
| struct sk_buff *skb, struct nf_conn *ct, |
| enum ip_conntrack_info ctinfo) |
| { |
| return NF_ACCEPT; |
| } |
| #endif |
| |
| /* Pass 'skb' through conntrack in 'net', using zone configured in 'info', if |
| * not done already. Update key with new CT state after passing the packet |
| * through conntrack. |
| * Note that if the packet is deemed invalid by conntrack, skb->_nfct will be |
| * set to NULL and 0 will be returned. |
| */ |
| static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key, |
| const struct ovs_conntrack_info *info, |
| struct sk_buff *skb) |
| { |
| /* If we are recirculating packets to match on conntrack fields and |
| * committing with a separate conntrack action, then we don't need to |
| * actually run the packet through conntrack twice unless it's for a |
| * different zone. |
| */ |
| bool cached = skb_nfct_cached(net, key, info, skb); |
| enum ip_conntrack_info ctinfo; |
| struct nf_conn *ct; |
| |
| if (!cached) { |
| struct nf_conn *tmpl = info->ct; |
| int err; |
| |
| /* Associate skb with specified zone. */ |
| if (tmpl) { |
| if (skb_nfct(skb)) |
| nf_conntrack_put(skb_nfct(skb)); |
| nf_conntrack_get(&tmpl->ct_general); |
| nf_ct_set(skb, tmpl, IP_CT_NEW); |
| } |
| |
| err = nf_conntrack_in(net, info->family, |
| NF_INET_PRE_ROUTING, skb); |
| if (err != NF_ACCEPT) |
| return -ENOENT; |
| |
| /* Clear CT state NAT flags to mark that we have not yet done |
| * NAT after the nf_conntrack_in() call. We can actually clear |
| * the whole state, as it will be re-initialized below. |
| */ |
| key->ct_state = 0; |
| |
| /* Update the key, but keep the NAT flags. */ |
| ovs_ct_update_key(skb, info, key, true, true); |
| } |
| |
| ct = nf_ct_get(skb, &ctinfo); |
| if (ct) { |
| /* Packets starting a new connection must be NATted before the |
| * helper, so that the helper knows about the NAT. We enforce |
| * this by delaying both NAT and helper calls for unconfirmed |
| * connections until the committing CT action. For later |
| * packets NAT and Helper may be called in either order. |
| * |
| * NAT will be done only if the CT action has NAT, and only |
| * once per packet (per zone), as guarded by the NAT bits in |
| * the key->ct_state. |
| */ |
| if (info->nat && !(key->ct_state & OVS_CS_F_NAT_MASK) && |
| (nf_ct_is_confirmed(ct) || info->commit) && |
| ovs_ct_nat(net, key, info, skb, ct, ctinfo) != NF_ACCEPT) { |
| return -EINVAL; |
| } |
| |
| /* Userspace may decide to perform a ct lookup without a helper |
| * specified followed by a (recirculate and) commit with one. |
| * Therefore, for unconfirmed connections which we will commit, |
| * we need to attach the helper here. |
| */ |
| if (!nf_ct_is_confirmed(ct) && info->commit && |
| info->helper && !nfct_help(ct)) { |
| int err = __nf_ct_try_assign_helper(ct, info->ct, |
| GFP_ATOMIC); |
| if (err) |
| return err; |
| } |
| |
| /* Call the helper only if: |
| * - nf_conntrack_in() was executed above ("!cached") for a |
| * confirmed connection, or |
| * - When committing an unconfirmed connection. |
| */ |
| if ((nf_ct_is_confirmed(ct) ? !cached : info->commit) && |
| ovs_ct_helper(skb, info->family) != NF_ACCEPT) { |
| return -EINVAL; |
| } |
| } |
| |
| return 0; |
| } |
| |
| /* Lookup connection and read fields into key. */ |
| static int ovs_ct_lookup(struct net *net, struct sw_flow_key *key, |
| const struct ovs_conntrack_info *info, |
| struct sk_buff *skb) |
| { |
| struct nf_conntrack_expect *exp; |
| |
| /* If we pass an expected packet through nf_conntrack_in() the |
| * expectation is typically removed, but the packet could still be |
| * lost in upcall processing. To prevent this from happening we |
| * perform an explicit expectation lookup. Expected connections are |
| * always new, and will be passed through conntrack only when they are |
| * committed, as it is OK to remove the expectation at that time. |
| */ |
| exp = ovs_ct_expect_find(net, &info->zone, info->family, skb); |
| if (exp) { |
| u8 state; |
| |
| /* NOTE: New connections are NATted and Helped only when |
| * committed, so we are not calling into NAT here. |
| */ |
| state = OVS_CS_F_TRACKED | OVS_CS_F_NEW | OVS_CS_F_RELATED; |
| __ovs_ct_update_key(key, state, &info->zone, exp->master); |
| } else { |
| struct nf_conn *ct; |
| int err; |
| |
| err = __ovs_ct_lookup(net, key, info, skb); |
| if (err) |
| return err; |
| |
| ct = (struct nf_conn *)skb_nfct(skb); |
| if (ct) |
| nf_ct_deliver_cached_events(ct); |
| } |
| |
| return 0; |
| } |
| |
| static bool labels_nonzero(const struct ovs_key_ct_labels *labels) |
| { |
| size_t i; |
| |
| for (i = 0; i < OVS_CT_LABELS_LEN_32; i++) |
| if (labels->ct_labels_32[i]) |
| return true; |
| |
| return false; |
| } |
| |
| /* Lookup connection and confirm if unconfirmed. */ |
| static int ovs_ct_commit(struct net *net, struct sw_flow_key *key, |
| const struct ovs_conntrack_info *info, |
| struct sk_buff *skb) |
| { |
| enum ip_conntrack_info ctinfo; |
| struct nf_conn *ct; |
| int err; |
| |
| err = __ovs_ct_lookup(net, key, info, skb); |
| if (err) |
| return err; |
| |
| /* The connection could be invalid, in which case this is a no-op.*/ |
| ct = nf_ct_get(skb, &ctinfo); |
| if (!ct) |
| return 0; |
| |
| /* Set the conntrack event mask if given. NEW and DELETE events have |
| * their own groups, but the NFNLGRP_CONNTRACK_UPDATE group listener |
| * typically would receive many kinds of updates. Setting the event |
| * mask allows those events to be filtered. The set event mask will |
| * remain in effect for the lifetime of the connection unless changed |
| * by a further CT action with both the commit flag and the eventmask |
| * option. */ |
| if (info->have_eventmask) { |
| struct nf_conntrack_ecache *cache = nf_ct_ecache_find(ct); |
| |
| if (cache) |
| cache->ctmask = info->eventmask; |
| } |
| |
| /* Apply changes before confirming the connection so that the initial |
| * conntrack NEW netlink event carries the values given in the CT |
| * action. |
| */ |
| if (info->mark.mask) { |
| err = ovs_ct_set_mark(ct, key, info->mark.value, |
| info->mark.mask); |
| if (err) |
| return err; |
| } |
| if (!nf_ct_is_confirmed(ct)) { |
| err = ovs_ct_init_labels(ct, key, &info->labels.value, |
| &info->labels.mask); |
| if (err) |
| return err; |
| } else if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && |
| labels_nonzero(&info->labels.mask)) { |
| err = ovs_ct_set_labels(ct, key, &info->labels.value, |
| &info->labels.mask); |
| if (err) |
| return err; |
| } |
| /* This will take care of sending queued events even if the connection |
| * is already confirmed. |
| */ |
| if (nf_conntrack_confirm(skb) != NF_ACCEPT) |
| return -EINVAL; |
| |
| return 0; |
| } |
| |
| /* Trim the skb to the length specified by the IP/IPv6 header, |
| * removing any trailing lower-layer padding. This prepares the skb |
| * for higher-layer processing that assumes skb->len excludes padding |
| * (such as nf_ip_checksum). The caller needs to pull the skb to the |
| * network header, and ensure ip_hdr/ipv6_hdr points to valid data. |
| */ |
| static int ovs_skb_network_trim(struct sk_buff *skb) |
| { |
| unsigned int len; |
| int err; |
| |
| switch (skb->protocol) { |
| case htons(ETH_P_IP): |
| len = ntohs(ip_hdr(skb)->tot_len); |
| break; |
| case htons(ETH_P_IPV6): |
| len = sizeof(struct ipv6hdr) |
| + ntohs(ipv6_hdr(skb)->payload_len); |
| break; |
| default: |
| len = skb->len; |
| } |
| |
| err = pskb_trim_rcsum(skb, len); |
| if (err) |
| kfree_skb(skb); |
| |
| return err; |
| } |
| |
| /* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero |
| * value if 'skb' is freed. |
| */ |
| int ovs_ct_execute(struct net *net, struct sk_buff *skb, |
| struct sw_flow_key *key, |
| const struct ovs_conntrack_info *info) |
| { |
| int nh_ofs; |
| int err; |
| |
| /* The conntrack module expects to be working at L3. */ |
| nh_ofs = skb_network_offset(skb); |
| skb_pull_rcsum(skb, nh_ofs); |
| |
| err = ovs_skb_network_trim(skb); |
| if (err) |
| return err; |
| |
| if (key->ip.frag != OVS_FRAG_TYPE_NONE) { |
| err = handle_fragments(net, key, info->zone.id, skb); |
| if (err) |
| return err; |
| } |
| |
| if (info->commit) |
| err = ovs_ct_commit(net, key, info, skb); |
| else |
| err = ovs_ct_lookup(net, key, info, skb); |
| |
| skb_push(skb, nh_ofs); |
| skb_postpush_rcsum(skb, skb->data, nh_ofs); |
| if (err) |
| kfree_skb(skb); |
| return err; |
| } |
| |
| static int ovs_ct_add_helper(struct ovs_conntrack_info *info, const char *name, |
| const struct sw_flow_key *key, bool log) |
| { |
| struct nf_conntrack_helper *helper; |
| struct nf_conn_help *help; |
| |
| helper = nf_conntrack_helper_try_module_get(name, info->family, |
| key->ip.proto); |
| if (!helper) { |
| OVS_NLERR(log, "Unknown helper \"%s\"", name); |
| return -EINVAL; |
| } |
| |
| help = nf_ct_helper_ext_add(info->ct, helper, GFP_KERNEL); |
| if (!help) { |
| nf_conntrack_helper_put(helper); |
| return -ENOMEM; |
| } |
| |
| rcu_assign_pointer(help->helper, helper); |
| info->helper = helper; |
| return 0; |
| } |
| |
| #ifdef CONFIG_NF_NAT_NEEDED |
| static int parse_nat(const struct nlattr *attr, |
| struct ovs_conntrack_info *info, bool log) |
| { |
| struct nlattr *a; |
| int rem; |
| bool have_ip_max = false; |
| bool have_proto_max = false; |
| bool ip_vers = (info->family == NFPROTO_IPV6); |
| |
| nla_for_each_nested(a, attr, rem) { |
| static const int ovs_nat_attr_lens[OVS_NAT_ATTR_MAX + 1][2] = { |
| [OVS_NAT_ATTR_SRC] = {0, 0}, |
| [OVS_NAT_ATTR_DST] = {0, 0}, |
| [OVS_NAT_ATTR_IP_MIN] = {sizeof(struct in_addr), |
| sizeof(struct in6_addr)}, |
| [OVS_NAT_ATTR_IP_MAX] = {sizeof(struct in_addr), |
| sizeof(struct in6_addr)}, |
| [OVS_NAT_ATTR_PROTO_MIN] = {sizeof(u16), sizeof(u16)}, |
| [OVS_NAT_ATTR_PROTO_MAX] = {sizeof(u16), sizeof(u16)}, |
| [OVS_NAT_ATTR_PERSISTENT] = {0, 0}, |
| [OVS_NAT_ATTR_PROTO_HASH] = {0, 0}, |
| [OVS_NAT_ATTR_PROTO_RANDOM] = {0, 0}, |
| }; |
| int type = nla_type(a); |
| |
| if (type > OVS_NAT_ATTR_MAX) { |
| OVS_NLERR(log, "Unknown NAT attribute (type=%d, max=%d)", |
| type, OVS_NAT_ATTR_MAX); |
| return -EINVAL; |
| } |
| |
| if (nla_len(a) != ovs_nat_attr_lens[type][ip_vers]) { |
| OVS_NLERR(log, "NAT attribute type %d has unexpected length (%d != %d)", |
| type, nla_len(a), |
| ovs_nat_attr_lens[type][ip_vers]); |
| return -EINVAL; |
| } |
| |
| switch (type) { |
| case OVS_NAT_ATTR_SRC: |
| case OVS_NAT_ATTR_DST: |
| if (info->nat) { |
| OVS_NLERR(log, "Only one type of NAT may be specified"); |
| return -ERANGE; |
| } |
| info->nat |= OVS_CT_NAT; |
| info->nat |= ((type == OVS_NAT_ATTR_SRC) |
| ? OVS_CT_SRC_NAT : OVS_CT_DST_NAT); |
| break; |
| |
| case OVS_NAT_ATTR_IP_MIN: |
| nla_memcpy(&info->range.min_addr, a, |
| sizeof(info->range.min_addr)); |
| info->range.flags |= NF_NAT_RANGE_MAP_IPS; |
| break; |
| |
| case OVS_NAT_ATTR_IP_MAX: |
| have_ip_max = true; |
| nla_memcpy(&info->range.max_addr, a, |
| sizeof(info->range.max_addr)); |
| info->range.flags |= NF_NAT_RANGE_MAP_IPS; |
| break; |
| |
| case OVS_NAT_ATTR_PROTO_MIN: |
| info->range.min_proto.all = htons(nla_get_u16(a)); |
| info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED; |
| break; |
| |
| case OVS_NAT_ATTR_PROTO_MAX: |
| have_proto_max = true; |
| info->range.max_proto.all = htons(nla_get_u16(a)); |
| info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED; |
| break; |
| |
| case OVS_NAT_ATTR_PERSISTENT: |
| info->range.flags |= NF_NAT_RANGE_PERSISTENT; |
| break; |
| |
| case OVS_NAT_ATTR_PROTO_HASH: |
| info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM; |
| break; |
| |
| case OVS_NAT_ATTR_PROTO_RANDOM: |
| info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM_FULLY; |
| break; |
| |
| default: |
| OVS_NLERR(log, "Unknown nat attribute (%d)", type); |
| return -EINVAL; |
| } |
| } |
| |
| if (rem > 0) { |
| OVS_NLERR(log, "NAT attribute has %d unknown bytes", rem); |
| return -EINVAL; |
| } |
| if (!info->nat) { |
| /* Do not allow flags if no type is given. */ |
| if (info->range.flags) { |
| OVS_NLERR(log, |
| "NAT flags may be given only when NAT range (SRC or DST) is also specified.\n" |
| ); |
| return -EINVAL; |
| } |
| info->nat = OVS_CT_NAT; /* NAT existing connections. */ |
| } else if (!info->commit) { |
| OVS_NLERR(log, |
| "NAT attributes may be specified only when CT COMMIT flag is also specified.\n" |
| ); |
| return -EINVAL; |
| } |
| /* Allow missing IP_MAX. */ |
| if (info->range.flags & NF_NAT_RANGE_MAP_IPS && !have_ip_max) { |
| memcpy(&info->range.max_addr, &info->range.min_addr, |
| sizeof(info->range.max_addr)); |
| } |
| /* Allow missing PROTO_MAX. */ |
| if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED && |
| !have_proto_max) { |
| info->range.max_proto.all = info->range.min_proto.all; |
| } |
| return 0; |
| } |
| #endif |
| |
| static const struct ovs_ct_len_tbl ovs_ct_attr_lens[OVS_CT_ATTR_MAX + 1] = { |
| [OVS_CT_ATTR_COMMIT] = { .minlen = 0, .maxlen = 0 }, |
| [OVS_CT_ATTR_FORCE_COMMIT] = { .minlen = 0, .maxlen = 0 }, |
| [OVS_CT_ATTR_ZONE] = { .minlen = sizeof(u16), |
| .maxlen = sizeof(u16) }, |
| [OVS_CT_ATTR_MARK] = { .minlen = sizeof(struct md_mark), |
| .maxlen = sizeof(struct md_mark) }, |
| [OVS_CT_ATTR_LABELS] = { .minlen = sizeof(struct md_labels), |
| .maxlen = sizeof(struct md_labels) }, |
| [OVS_CT_ATTR_HELPER] = { .minlen = 1, |
| .maxlen = NF_CT_HELPER_NAME_LEN }, |
| #ifdef CONFIG_NF_NAT_NEEDED |
| /* NAT length is checked when parsing the nested attributes. */ |
| [OVS_CT_ATTR_NAT] = { .minlen = 0, .maxlen = INT_MAX }, |
| #endif |
| [OVS_CT_ATTR_EVENTMASK] = { .minlen = sizeof(u32), |
| .maxlen = sizeof(u32) }, |
| }; |
| |
| static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info, |
| const char **helper, bool log) |
| { |
| struct nlattr *a; |
| int rem; |
| |
| nla_for_each_nested(a, attr, rem) { |
| int type = nla_type(a); |
| int maxlen; |
| int minlen; |
| |
| if (type > OVS_CT_ATTR_MAX) { |
| OVS_NLERR(log, |
| "Unknown conntrack attr (type=%d, max=%d)", |
| type, OVS_CT_ATTR_MAX); |
| return -EINVAL; |
| } |
| |
| maxlen = ovs_ct_attr_lens[type].maxlen; |
| minlen = ovs_ct_attr_lens[type].minlen; |
| if (nla_len(a) < minlen || nla_len(a) > maxlen) { |
| OVS_NLERR(log, |
| "Conntrack attr type has unexpected length (type=%d, length=%d, expected=%d)", |
| type, nla_len(a), maxlen); |
| return -EINVAL; |
| } |
| |
| switch (type) { |
| case OVS_CT_ATTR_FORCE_COMMIT: |
| info->force = true; |
| /* fall through. */ |
| case OVS_CT_ATTR_COMMIT: |
| info->commit = true; |
| break; |
| #ifdef CONFIG_NF_CONNTRACK_ZONES |
| case OVS_CT_ATTR_ZONE: |
| info->zone.id = nla_get_u16(a); |
| break; |
| #endif |
| #ifdef CONFIG_NF_CONNTRACK_MARK |
| case OVS_CT_ATTR_MARK: { |
| struct md_mark *mark = nla_data(a); |
| |
| if (!mark->mask) { |
| OVS_NLERR(log, "ct_mark mask cannot be 0"); |
| return -EINVAL; |
| } |
| info->mark = *mark; |
| break; |
| } |
| #endif |
| #ifdef CONFIG_NF_CONNTRACK_LABELS |
| case OVS_CT_ATTR_LABELS: { |
| struct md_labels *labels = nla_data(a); |
| |
| if (!labels_nonzero(&labels->mask)) { |
| OVS_NLERR(log, "ct_labels mask cannot be 0"); |
| return -EINVAL; |
| } |
| info->labels = *labels; |
| break; |
| } |
| #endif |
| case OVS_CT_ATTR_HELPER: |
| *helper = nla_data(a); |
| if (!memchr(*helper, '\0', nla_len(a))) { |
| OVS_NLERR(log, "Invalid conntrack helper"); |
| return -EINVAL; |
| } |
| break; |
| #ifdef CONFIG_NF_NAT_NEEDED |
| case OVS_CT_ATTR_NAT: { |
| int err = parse_nat(a, info, log); |
| |
| if (err) |
| return err; |
| break; |
| } |
| #endif |
| case OVS_CT_ATTR_EVENTMASK: |
| info->have_eventmask = true; |
| info->eventmask = nla_get_u32(a); |
| break; |
| |
| default: |
| OVS_NLERR(log, "Unknown conntrack attr (%d)", |
| type); |
| return -EINVAL; |
| } |
| } |
| |
| #ifdef CONFIG_NF_CONNTRACK_MARK |
| if (!info->commit && info->mark.mask) { |
| OVS_NLERR(log, |
| "Setting conntrack mark requires 'commit' flag."); |
| return -EINVAL; |
| } |
| #endif |
| #ifdef CONFIG_NF_CONNTRACK_LABELS |
| if (!info->commit && labels_nonzero(&info->labels.mask)) { |
| OVS_NLERR(log, |
| "Setting conntrack labels requires 'commit' flag."); |
| return -EINVAL; |
| } |
| #endif |
| if (rem > 0) { |
| OVS_NLERR(log, "Conntrack attr has %d unknown bytes", rem); |
| return -EINVAL; |
| } |
| |
| return 0; |
| } |
| |
| bool ovs_ct_verify(struct net *net, enum ovs_key_attr attr) |
| { |
| if (attr == OVS_KEY_ATTR_CT_STATE) |
| return true; |
| if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && |
| attr == OVS_KEY_ATTR_CT_ZONE) |
| return true; |
| if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && |
| attr == OVS_KEY_ATTR_CT_MARK) |
| return true; |
| if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && |
| attr == OVS_KEY_ATTR_CT_LABELS) { |
| struct ovs_net *ovs_net = net_generic(net, ovs_net_id); |
| |
| return ovs_net->xt_label; |
| } |
| |
| return false; |
| } |
| |
| int ovs_ct_copy_action(struct net *net, const struct nlattr *attr, |
| const struct sw_flow_key *key, |
| struct sw_flow_actions **sfa, bool log) |
| { |
| struct ovs_conntrack_info ct_info; |
| const char *helper = NULL; |
| u16 family; |
| int err; |
| |
| family = key_to_nfproto(key); |
| if (family == NFPROTO_UNSPEC) { |
| OVS_NLERR(log, "ct family unspecified"); |
| return -EINVAL; |
| } |
| |
| memset(&ct_info, 0, sizeof(ct_info)); |
| ct_info.family = family; |
| |
| nf_ct_zone_init(&ct_info.zone, NF_CT_DEFAULT_ZONE_ID, |
| NF_CT_DEFAULT_ZONE_DIR, 0); |
| |
| err = parse_ct(attr, &ct_info, &helper, log); |
| if (err) |
| return err; |
| |
| /* Set up template for tracking connections in specific zones. */ |
| ct_info.ct = nf_ct_tmpl_alloc(net, &ct_info.zone, GFP_KERNEL); |
| if (!ct_info.ct) { |
| OVS_NLERR(log, "Failed to allocate conntrack template"); |
| return -ENOMEM; |
| } |
| |
| __set_bit(IPS_CONFIRMED_BIT, &ct_info.ct->status); |
| nf_conntrack_get(&ct_info.ct->ct_general); |
| |
| if (helper) { |
| err = ovs_ct_add_helper(&ct_info, helper, key, log); |
| if (err) |
| goto err_free_ct; |
| } |
| |
| err = ovs_nla_add_action(sfa, OVS_ACTION_ATTR_CT, &ct_info, |
| sizeof(ct_info), log); |
| if (err) |
| goto err_free_ct; |
| |
| return 0; |
| err_free_ct: |
| __ovs_ct_free_action(&ct_info); |
| return err; |
| } |
| |
| #ifdef CONFIG_NF_NAT_NEEDED |
| static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info, |
| struct sk_buff *skb) |
| { |
| struct nlattr *start; |
| |
| start = nla_nest_start(skb, OVS_CT_ATTR_NAT); |
| if (!start) |
| return false; |
| |
| if (info->nat & OVS_CT_SRC_NAT) { |
| if (nla_put_flag(skb, OVS_NAT_ATTR_SRC)) |
| return false; |
| } else if (info->nat & OVS_CT_DST_NAT) { |
| if (nla_put_flag(skb, OVS_NAT_ATTR_DST)) |
| return false; |
| } else { |
| goto out; |
| } |
| |
| if (info->range.flags & NF_NAT_RANGE_MAP_IPS) { |
| if (IS_ENABLED(CONFIG_NF_NAT_IPV4) && |
| info->family == NFPROTO_IPV4) { |
| if (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MIN, |
| info->range.min_addr.ip) || |
| (info->range.max_addr.ip |
| != info->range.min_addr.ip && |
| (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MAX, |
| info->range.max_addr.ip)))) |
| return false; |
| } else if (IS_ENABLED(CONFIG_NF_NAT_IPV6) && |
| info->family == NFPROTO_IPV6) { |
| if (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MIN, |
| &info->range.min_addr.in6) || |
| (memcmp(&info->range.max_addr.in6, |
| &info->range.min_addr.in6, |
| sizeof(info->range.max_addr.in6)) && |
| (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MAX, |
| &info->range.max_addr.in6)))) |
| return false; |
| } else { |
| return false; |
| } |
| } |
| if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED && |
| (nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MIN, |
| ntohs(info->range.min_proto.all)) || |
| (info->range.max_proto.all != info->range.min_proto.all && |
| nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MAX, |
| ntohs(info->range.max_proto.all))))) |
| return false; |
| |
| if (info->range.flags & NF_NAT_RANGE_PERSISTENT && |
| nla_put_flag(skb, OVS_NAT_ATTR_PERSISTENT)) |
| return false; |
| if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM && |
| nla_put_flag(skb, OVS_NAT_ATTR_PROTO_HASH)) |
| return false; |
| if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM_FULLY && |
| nla_put_flag(skb, OVS_NAT_ATTR_PROTO_RANDOM)) |
| return false; |
| out: |
| nla_nest_end(skb, start); |
| |
| return true; |
| } |
| #endif |
| |
| int ovs_ct_action_to_attr(const struct ovs_conntrack_info *ct_info, |
| struct sk_buff *skb) |
| { |
| struct nlattr *start; |
| |
| start = nla_nest_start(skb, OVS_ACTION_ATTR_CT); |
| if (!start) |
| return -EMSGSIZE; |
| |
| if (ct_info->commit && nla_put_flag(skb, ct_info->force |
| ? OVS_CT_ATTR_FORCE_COMMIT |
| : OVS_CT_ATTR_COMMIT)) |
| return -EMSGSIZE; |
| if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && |
| nla_put_u16(skb, OVS_CT_ATTR_ZONE, ct_info->zone.id)) |
| return -EMSGSIZE; |
| if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && ct_info->mark.mask && |
| nla_put(skb, OVS_CT_ATTR_MARK, sizeof(ct_info->mark), |
| &ct_info->mark)) |
| return -EMSGSIZE; |
| if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && |
| labels_nonzero(&ct_info->labels.mask) && |
| nla_put(skb, OVS_CT_ATTR_LABELS, sizeof(ct_info->labels), |
| &ct_info->labels)) |
| return -EMSGSIZE; |
| if (ct_info->helper) { |
| if (nla_put_string(skb, OVS_CT_ATTR_HELPER, |
| ct_info->helper->name)) |
| return -EMSGSIZE; |
| } |
| if (ct_info->have_eventmask && |
| nla_put_u32(skb, OVS_CT_ATTR_EVENTMASK, ct_info->eventmask)) |
| return -EMSGSIZE; |
| |
| #ifdef CONFIG_NF_NAT_NEEDED |
| if (ct_info->nat && !ovs_ct_nat_to_attr(ct_info, skb)) |
| return -EMSGSIZE; |
| #endif |
| nla_nest_end(skb, start); |
| |
| return 0; |
| } |
| |
| void ovs_ct_free_action(const struct nlattr *a) |
| { |
| struct ovs_conntrack_info *ct_info = nla_data(a); |
| |
| __ovs_ct_free_action(ct_info); |
| } |
| |
| static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info) |
| { |
| if (ct_info->helper) |
| nf_conntrack_helper_put(ct_info->helper); |
| if (ct_info->ct) |
| nf_ct_tmpl_free(ct_info->ct); |
| } |
| |
| void ovs_ct_init(struct net *net) |
| { |
| unsigned int n_bits = sizeof(struct ovs_key_ct_labels) * BITS_PER_BYTE; |
| struct ovs_net *ovs_net = net_generic(net, ovs_net_id); |
| |
| if (nf_connlabels_get(net, n_bits - 1)) { |
| ovs_net->xt_label = false; |
| OVS_NLERR(true, "Failed to set connlabel length"); |
| } else { |
| ovs_net->xt_label = true; |
| } |
| } |
| |
| void ovs_ct_exit(struct net *net) |
| { |
| struct ovs_net *ovs_net = net_generic(net, ovs_net_id); |
| |
| if (ovs_net->xt_label) |
| nf_connlabels_put(net); |
| } |