diff options
Diffstat (limited to 'net/openvswitch/conntrack.c')
| -rw-r--r-- | net/openvswitch/conntrack.c | 1999 |
1 files changed, 1999 insertions, 0 deletions
diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c new file mode 100644 index 0000000000..3019a4406c --- /dev/null +++ b/net/openvswitch/conntrack.c @@ -0,0 +1,1999 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2015 Nicira, Inc. + */ + +#include <linux/module.h> +#include <linux/openvswitch.h> +#include <linux/tcp.h> +#include <linux/udp.h> +#include <linux/sctp.h> +#include <linux/static_key.h> +#include <linux/string_helpers.h> +#include <net/ip.h> +#include <net/genetlink.h> +#include <net/netfilter/nf_conntrack_core.h> +#include <net/netfilter/nf_conntrack_count.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_timeout.h> +#include <net/netfilter/nf_conntrack_zones.h> +#include <net/netfilter/ipv6/nf_defrag_ipv6.h> +#include <net/ipv6_frag.h> + +#if IS_ENABLED(CONFIG_NF_NAT) +#include <net/netfilter/nf_nat.h> +#endif + +#include <net/netfilter/nf_conntrack_act_ct.h> + +#include "datapath.h" +#include "drop.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; + char timeout[CTNL_TIMEOUT_NAME_MAX]; + struct nf_ct_timeout *nf_ct_timeout; +#if IS_ENABLED(CONFIG_NF_NAT) + struct nf_nat_range2 range; /* Only present for SRC NAT and DST NAT. */ +#endif +}; + +#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) +#define OVS_CT_LIMIT_UNLIMITED 0 +#define OVS_CT_LIMIT_DEFAULT OVS_CT_LIMIT_UNLIMITED +#define CT_LIMIT_HASH_BUCKETS 512 +static DEFINE_STATIC_KEY_FALSE(ovs_ct_limit_enabled); + +struct ovs_ct_limit { + /* Elements in ovs_ct_limit_info->limits hash table */ + struct hlist_node hlist_node; + struct rcu_head rcu; + u16 zone; + u32 limit; +}; + +struct ovs_ct_limit_info { + u32 default_limit; + struct hlist_head *limits; + struct nf_conncount_data *data; +}; + +static const struct nla_policy ct_limit_policy[OVS_CT_LIMIT_ATTR_MAX + 1] = { + [OVS_CT_LIMIT_ATTR_ZONE_LIMIT] = { .type = NLA_NESTED, }, +}; +#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 ? READ_ONCE(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, + bool post_ct) +{ + ovs_ct_update_key(skb, NULL, key, post_ct, 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 | (READ_ONCE(ct->mark) & ~(mask)); + if (READ_ONCE(ct->mark) != new_mark) { + WRITE_ONCE(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; +} + +static int ovs_ct_handle_fragments(struct net *net, struct sw_flow_key *key, + u16 zone, int family, struct sk_buff *skb) +{ + struct ovs_skb_cb ovs_cb = *OVS_CB(skb); + int err; + + err = nf_ct_handle_fragments(net, skb, zone, family, &key->ip.proto, &ovs_cb.mru); + if (err) + return err; + + /* The key extracted from the fragment that completed this datagram + * likely didn't have an L4 header, so regenerate it. + */ + ovs_flow_key_update_l3l4(skb, key); + key->ip.frag = OVS_FRAG_TYPE_NONE; + *OVS_CB(skb) = ovs_cb; + + return 0; +} + +/* 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) +{ + struct nf_conntrack_tuple tuple; + struct nf_conntrack_tuple_hash *h; + struct nf_conn *ct; + + if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb), l3num, + net, &tuple)) { + 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)) { + 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; + } + if (info->nf_ct_timeout) { + struct nf_conn_timeout *timeout_ext; + + timeout_ext = nf_ct_timeout_find(ct); + if (!timeout_ext || info->nf_ct_timeout != + rcu_dereference(timeout_ext->timeout)) + 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_ct_put(ct); + nf_ct_set(skb, NULL, 0); + return false; + } + + return ct_executed; +} + +#if IS_ENABLED(CONFIG_NF_NAT) +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) +{ + int err, action = 0; + + if (!(info->nat & OVS_CT_NAT)) + return NF_ACCEPT; + if (info->nat & OVS_CT_SRC_NAT) + action |= BIT(NF_NAT_MANIP_SRC); + if (info->nat & OVS_CT_DST_NAT) + action |= BIT(NF_NAT_MANIP_DST); + + err = nf_ct_nat(skb, ct, ctinfo, &action, &info->range, info->commit); + + if (action & BIT(NF_NAT_MANIP_SRC)) + ovs_nat_update_key(key, skb, NF_NAT_MANIP_SRC); + if (action & BIT(NF_NAT_MANIP_DST)) + ovs_nat_update_key(key, skb, NF_NAT_MANIP_DST); + + return err; +} +#else /* !CONFIG_NF_NAT */ +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_hook_state state = { + .hook = NF_INET_PRE_ROUTING, + .pf = info->family, + .net = net, + }; + struct nf_conn *tmpl = info->ct; + int err; + + /* Associate skb with specified zone. */ + if (tmpl) { + ct = nf_ct_get(skb, &ctinfo); + nf_ct_put(ct); + nf_conntrack_get(&tmpl->ct_general); + nf_ct_set(skb, tmpl, IP_CT_NEW); + } + + err = nf_conntrack_in(skb, &state); + 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) { + bool add_helper = false; + + /* 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, + * or attach a helper in a later commit. Therefore, for + * connections which we will commit, we may 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; + add_helper = true; + + /* helper installed, add seqadj if NAT is required */ + if (info->nat && !nfct_seqadj(ct)) { + if (!nfct_seqadj_ext_add(ct)) + return -EINVAL; + } + } + + /* Call the helper only if: + * - nf_conntrack_in() was executed above ("!cached") or a + * helper was just attached ("add_helper") for a confirmed + * connection, or + * - When committing an unconfirmed connection. + */ + if ((nf_ct_is_confirmed(ct) ? !cached || add_helper : + info->commit) && + nf_ct_helper(skb, ct, ctinfo, info->family) != NF_ACCEPT) { + return -EINVAL; + } + + if (nf_ct_protonum(ct) == IPPROTO_TCP && + nf_ct_is_confirmed(ct) && nf_conntrack_tcp_established(ct)) { + /* Be liberal for tcp packets so that out-of-window + * packets are not marked invalid. + */ + nf_ct_set_tcp_be_liberal(ct); + } + + nf_conn_act_ct_ext_fill(skb, ct, ctinfo); + } + + 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_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; +} + +#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) +static struct hlist_head *ct_limit_hash_bucket( + const struct ovs_ct_limit_info *info, u16 zone) +{ + return &info->limits[zone & (CT_LIMIT_HASH_BUCKETS - 1)]; +} + +/* Call with ovs_mutex */ +static void ct_limit_set(const struct ovs_ct_limit_info *info, + struct ovs_ct_limit *new_ct_limit) +{ + struct ovs_ct_limit *ct_limit; + struct hlist_head *head; + + head = ct_limit_hash_bucket(info, new_ct_limit->zone); + hlist_for_each_entry_rcu(ct_limit, head, hlist_node) { + if (ct_limit->zone == new_ct_limit->zone) { + hlist_replace_rcu(&ct_limit->hlist_node, + &new_ct_limit->hlist_node); + kfree_rcu(ct_limit, rcu); + return; + } + } + + hlist_add_head_rcu(&new_ct_limit->hlist_node, head); +} + +/* Call with ovs_mutex */ +static void ct_limit_del(const struct ovs_ct_limit_info *info, u16 zone) +{ + struct ovs_ct_limit *ct_limit; + struct hlist_head *head; + struct hlist_node *n; + + head = ct_limit_hash_bucket(info, zone); + hlist_for_each_entry_safe(ct_limit, n, head, hlist_node) { + if (ct_limit->zone == zone) { + hlist_del_rcu(&ct_limit->hlist_node); + kfree_rcu(ct_limit, rcu); + return; + } + } +} + +/* Call with RCU read lock */ +static u32 ct_limit_get(const struct ovs_ct_limit_info *info, u16 zone) +{ + struct ovs_ct_limit *ct_limit; + struct hlist_head *head; + + head = ct_limit_hash_bucket(info, zone); + hlist_for_each_entry_rcu(ct_limit, head, hlist_node) { + if (ct_limit->zone == zone) + return ct_limit->limit; + } + + return info->default_limit; +} + +static int ovs_ct_check_limit(struct net *net, + const struct ovs_conntrack_info *info, + const struct nf_conntrack_tuple *tuple) +{ + struct ovs_net *ovs_net = net_generic(net, ovs_net_id); + const struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; + u32 per_zone_limit, connections; + u32 conncount_key; + + conncount_key = info->zone.id; + + per_zone_limit = ct_limit_get(ct_limit_info, info->zone.id); + if (per_zone_limit == OVS_CT_LIMIT_UNLIMITED) + return 0; + + connections = nf_conncount_count(net, ct_limit_info->data, + &conncount_key, tuple, &info->zone); + if (connections > per_zone_limit) + return -ENOMEM; + + return 0; +} +#endif + +/* 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; + +#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) + if (static_branch_unlikely(&ovs_ct_limit_enabled)) { + if (!nf_ct_is_confirmed(ct)) { + err = ovs_ct_check_limit(net, info, + &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); + if (err) { + net_warn_ratelimited("openvswitch: zone: %u " + "exceeds conntrack limit\n", + info->zone.id); + return err; + } + } + } +#endif + + /* 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; + + nf_conn_act_ct_ext_add(skb, ct, ctinfo); + } 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; +} + +/* 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 = nf_ct_skb_network_trim(skb, info->family); + if (err) { + kfree_skb(skb); + return err; + } + + if (key->ip.frag != OVS_FRAG_TYPE_NONE) { + err = ovs_ct_handle_fragments(net, key, info->zone.id, + info->family, 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_rcsum(skb, nh_ofs); + if (err) + ovs_kfree_skb_reason(skb, OVS_DROP_CONNTRACK); + return err; +} + +int ovs_ct_clear(struct sk_buff *skb, struct sw_flow_key *key) +{ + enum ip_conntrack_info ctinfo; + struct nf_conn *ct; + + ct = nf_ct_get(skb, &ctinfo); + + nf_ct_put(ct); + nf_ct_set(skb, NULL, IP_CT_UNTRACKED); + + if (key) + ovs_ct_fill_key(skb, key, false); + + return 0; +} + +#if IS_ENABLED(CONFIG_NF_NAT) +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." + ); + 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." + ); + 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 }, +#if IS_ENABLED(CONFIG_NF_NAT) + /* 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) }, + [OVS_CT_ATTR_TIMEOUT] = { .minlen = 1, + .maxlen = CTNL_TIMEOUT_NAME_MAX }, +}; + +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; + fallthrough; + 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 (!string_is_terminated(*helper, nla_len(a))) { + OVS_NLERR(log, "Invalid conntrack helper"); + return -EINVAL; + } + break; +#if IS_ENABLED(CONFIG_NF_NAT) + 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; +#ifdef CONFIG_NF_CONNTRACK_TIMEOUT + case OVS_CT_ATTR_TIMEOUT: + memcpy(info->timeout, nla_data(a), nla_len(a)); + if (!string_is_terminated(info->timeout, nla_len(a))) { + OVS_NLERR(log, "Invalid conntrack timeout"); + return -EINVAL; + } + break; +#endif + + 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; + } + + if (ct_info.timeout[0]) { + if (nf_ct_set_timeout(net, ct_info.ct, family, key->ip.proto, + ct_info.timeout)) + pr_info_ratelimited("Failed to associated timeout " + "policy `%s'\n", ct_info.timeout); + else + ct_info.nf_ct_timeout = rcu_dereference( + nf_ct_timeout_find(ct_info.ct)->timeout); + + } + + if (helper) { + err = nf_ct_add_helper(ct_info.ct, helper, ct_info.family, + key->ip.proto, ct_info.nat, &ct_info.helper); + if (err) { + OVS_NLERR(log, "Failed to add %s helper %d", helper, 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; + + if (ct_info.commit) + __set_bit(IPS_CONFIRMED_BIT, &ct_info.ct->status); + return 0; +err_free_ct: + __ovs_ct_free_action(&ct_info); + return err; +} + +#if IS_ENABLED(CONFIG_NF_NAT) +static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info, + struct sk_buff *skb) +{ + struct nlattr *start; + + start = nla_nest_start_noflag(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) && + 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_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_noflag(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; + if (ct_info->timeout[0]) { + if (nla_put_string(skb, OVS_CT_ATTR_TIMEOUT, ct_info->timeout)) + return -EMSGSIZE; + } + +#if IS_ENABLED(CONFIG_NF_NAT) + 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) { +#if IS_ENABLED(CONFIG_NF_NAT) + if (ct_info->nat) + nf_nat_helper_put(ct_info->helper); +#endif + nf_conntrack_helper_put(ct_info->helper); + } + if (ct_info->ct) { + if (ct_info->timeout[0]) + nf_ct_destroy_timeout(ct_info->ct); + nf_ct_tmpl_free(ct_info->ct); + } +} + +#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) +static int ovs_ct_limit_init(struct net *net, struct ovs_net *ovs_net) +{ + int i, err; + + ovs_net->ct_limit_info = kmalloc(sizeof(*ovs_net->ct_limit_info), + GFP_KERNEL); + if (!ovs_net->ct_limit_info) + return -ENOMEM; + + ovs_net->ct_limit_info->default_limit = OVS_CT_LIMIT_DEFAULT; + ovs_net->ct_limit_info->limits = + kmalloc_array(CT_LIMIT_HASH_BUCKETS, sizeof(struct hlist_head), + GFP_KERNEL); + if (!ovs_net->ct_limit_info->limits) { + kfree(ovs_net->ct_limit_info); + return -ENOMEM; + } + + for (i = 0; i < CT_LIMIT_HASH_BUCKETS; i++) + INIT_HLIST_HEAD(&ovs_net->ct_limit_info->limits[i]); + + ovs_net->ct_limit_info->data = + nf_conncount_init(net, NFPROTO_INET, sizeof(u32)); + + if (IS_ERR(ovs_net->ct_limit_info->data)) { + err = PTR_ERR(ovs_net->ct_limit_info->data); + kfree(ovs_net->ct_limit_info->limits); + kfree(ovs_net->ct_limit_info); + pr_err("openvswitch: failed to init nf_conncount %d\n", err); + return err; + } + return 0; +} + +static void ovs_ct_limit_exit(struct net *net, struct ovs_net *ovs_net) +{ + const struct ovs_ct_limit_info *info = ovs_net->ct_limit_info; + int i; + + nf_conncount_destroy(net, NFPROTO_INET, info->data); + for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) { + struct hlist_head *head = &info->limits[i]; + struct ovs_ct_limit *ct_limit; + + hlist_for_each_entry_rcu(ct_limit, head, hlist_node, + lockdep_ovsl_is_held()) + kfree_rcu(ct_limit, rcu); + } + kfree(info->limits); + kfree(info); +} + +static struct sk_buff * +ovs_ct_limit_cmd_reply_start(struct genl_info *info, u8 cmd, + struct ovs_header **ovs_reply_header) +{ + struct ovs_header *ovs_header = genl_info_userhdr(info); + struct sk_buff *skb; + + skb = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!skb) + return ERR_PTR(-ENOMEM); + + *ovs_reply_header = genlmsg_put(skb, info->snd_portid, + info->snd_seq, + &dp_ct_limit_genl_family, 0, cmd); + + if (!*ovs_reply_header) { + nlmsg_free(skb); + return ERR_PTR(-EMSGSIZE); + } + (*ovs_reply_header)->dp_ifindex = ovs_header->dp_ifindex; + + return skb; +} + +static bool check_zone_id(int zone_id, u16 *pzone) +{ + if (zone_id >= 0 && zone_id <= 65535) { + *pzone = (u16)zone_id; + return true; + } + return false; +} + +static int ovs_ct_limit_set_zone_limit(struct nlattr *nla_zone_limit, + struct ovs_ct_limit_info *info) +{ + struct ovs_zone_limit *zone_limit; + int rem; + u16 zone; + + rem = NLA_ALIGN(nla_len(nla_zone_limit)); + zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit); + + while (rem >= sizeof(*zone_limit)) { + if (unlikely(zone_limit->zone_id == + OVS_ZONE_LIMIT_DEFAULT_ZONE)) { + ovs_lock(); + info->default_limit = zone_limit->limit; + ovs_unlock(); + } else if (unlikely(!check_zone_id( + zone_limit->zone_id, &zone))) { + OVS_NLERR(true, "zone id is out of range"); + } else { + struct ovs_ct_limit *ct_limit; + + ct_limit = kmalloc(sizeof(*ct_limit), + GFP_KERNEL_ACCOUNT); + if (!ct_limit) + return -ENOMEM; + + ct_limit->zone = zone; + ct_limit->limit = zone_limit->limit; + + ovs_lock(); + ct_limit_set(info, ct_limit); + ovs_unlock(); + } + rem -= NLA_ALIGN(sizeof(*zone_limit)); + zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit + + NLA_ALIGN(sizeof(*zone_limit))); + } + + if (rem) + OVS_NLERR(true, "set zone limit has %d unknown bytes", rem); + + return 0; +} + +static int ovs_ct_limit_del_zone_limit(struct nlattr *nla_zone_limit, + struct ovs_ct_limit_info *info) +{ + struct ovs_zone_limit *zone_limit; + int rem; + u16 zone; + + rem = NLA_ALIGN(nla_len(nla_zone_limit)); + zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit); + + while (rem >= sizeof(*zone_limit)) { + if (unlikely(zone_limit->zone_id == + OVS_ZONE_LIMIT_DEFAULT_ZONE)) { + ovs_lock(); + info->default_limit = OVS_CT_LIMIT_DEFAULT; + ovs_unlock(); + } else if (unlikely(!check_zone_id( + zone_limit->zone_id, &zone))) { + OVS_NLERR(true, "zone id is out of range"); + } else { + ovs_lock(); + ct_limit_del(info, zone); + ovs_unlock(); + } + rem -= NLA_ALIGN(sizeof(*zone_limit)); + zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit + + NLA_ALIGN(sizeof(*zone_limit))); + } + + if (rem) + OVS_NLERR(true, "del zone limit has %d unknown bytes", rem); + + return 0; +} + +static int ovs_ct_limit_get_default_limit(struct ovs_ct_limit_info *info, + struct sk_buff *reply) +{ + struct ovs_zone_limit zone_limit = { + .zone_id = OVS_ZONE_LIMIT_DEFAULT_ZONE, + .limit = info->default_limit, + }; + + return nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit); +} + +static int __ovs_ct_limit_get_zone_limit(struct net *net, + struct nf_conncount_data *data, + u16 zone_id, u32 limit, + struct sk_buff *reply) +{ + struct nf_conntrack_zone ct_zone; + struct ovs_zone_limit zone_limit; + u32 conncount_key = zone_id; + + zone_limit.zone_id = zone_id; + zone_limit.limit = limit; + nf_ct_zone_init(&ct_zone, zone_id, NF_CT_DEFAULT_ZONE_DIR, 0); + + zone_limit.count = nf_conncount_count(net, data, &conncount_key, NULL, + &ct_zone); + return nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit); +} + +static int ovs_ct_limit_get_zone_limit(struct net *net, + struct nlattr *nla_zone_limit, + struct ovs_ct_limit_info *info, + struct sk_buff *reply) +{ + struct ovs_zone_limit *zone_limit; + int rem, err; + u32 limit; + u16 zone; + + rem = NLA_ALIGN(nla_len(nla_zone_limit)); + zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit); + + while (rem >= sizeof(*zone_limit)) { + if (unlikely(zone_limit->zone_id == + OVS_ZONE_LIMIT_DEFAULT_ZONE)) { + err = ovs_ct_limit_get_default_limit(info, reply); + if (err) + return err; + } else if (unlikely(!check_zone_id(zone_limit->zone_id, + &zone))) { + OVS_NLERR(true, "zone id is out of range"); + } else { + rcu_read_lock(); + limit = ct_limit_get(info, zone); + rcu_read_unlock(); + + err = __ovs_ct_limit_get_zone_limit( + net, info->data, zone, limit, reply); + if (err) + return err; + } + rem -= NLA_ALIGN(sizeof(*zone_limit)); + zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit + + NLA_ALIGN(sizeof(*zone_limit))); + } + + if (rem) + OVS_NLERR(true, "get zone limit has %d unknown bytes", rem); + + return 0; +} + +static int ovs_ct_limit_get_all_zone_limit(struct net *net, + struct ovs_ct_limit_info *info, + struct sk_buff *reply) +{ + struct ovs_ct_limit *ct_limit; + struct hlist_head *head; + int i, err = 0; + + err = ovs_ct_limit_get_default_limit(info, reply); + if (err) + return err; + + rcu_read_lock(); + for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) { + head = &info->limits[i]; + hlist_for_each_entry_rcu(ct_limit, head, hlist_node) { + err = __ovs_ct_limit_get_zone_limit(net, info->data, + ct_limit->zone, ct_limit->limit, reply); + if (err) + goto exit_err; + } + } + +exit_err: + rcu_read_unlock(); + return err; +} + +static int ovs_ct_limit_cmd_set(struct sk_buff *skb, struct genl_info *info) +{ + struct nlattr **a = info->attrs; + struct sk_buff *reply; + struct ovs_header *ovs_reply_header; + struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id); + struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; + int err; + + reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_SET, + &ovs_reply_header); + if (IS_ERR(reply)) + return PTR_ERR(reply); + + if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) { + err = -EINVAL; + goto exit_err; + } + + err = ovs_ct_limit_set_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], + ct_limit_info); + if (err) + goto exit_err; + + static_branch_enable(&ovs_ct_limit_enabled); + + genlmsg_end(reply, ovs_reply_header); + return genlmsg_reply(reply, info); + +exit_err: + nlmsg_free(reply); + return err; +} + +static int ovs_ct_limit_cmd_del(struct sk_buff *skb, struct genl_info *info) +{ + struct nlattr **a = info->attrs; + struct sk_buff *reply; + struct ovs_header *ovs_reply_header; + struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id); + struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; + int err; + + reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_DEL, + &ovs_reply_header); + if (IS_ERR(reply)) + return PTR_ERR(reply); + + if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) { + err = -EINVAL; + goto exit_err; + } + + err = ovs_ct_limit_del_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], + ct_limit_info); + if (err) + goto exit_err; + + genlmsg_end(reply, ovs_reply_header); + return genlmsg_reply(reply, info); + +exit_err: + nlmsg_free(reply); + return err; +} + +static int ovs_ct_limit_cmd_get(struct sk_buff *skb, struct genl_info *info) +{ + struct nlattr **a = info->attrs; + struct nlattr *nla_reply; + struct sk_buff *reply; + struct ovs_header *ovs_reply_header; + struct net *net = sock_net(skb->sk); + struct ovs_net *ovs_net = net_generic(net, ovs_net_id); + struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; + int err; + + reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_GET, + &ovs_reply_header); + if (IS_ERR(reply)) + return PTR_ERR(reply); + + nla_reply = nla_nest_start_noflag(reply, OVS_CT_LIMIT_ATTR_ZONE_LIMIT); + if (!nla_reply) { + err = -EMSGSIZE; + goto exit_err; + } + + if (a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) { + err = ovs_ct_limit_get_zone_limit( + net, a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], ct_limit_info, + reply); + if (err) + goto exit_err; + } else { + err = ovs_ct_limit_get_all_zone_limit(net, ct_limit_info, + reply); + if (err) + goto exit_err; + } + + nla_nest_end(reply, nla_reply); + genlmsg_end(reply, ovs_reply_header); + return genlmsg_reply(reply, info); + +exit_err: + nlmsg_free(reply); + return err; +} + +static const struct genl_small_ops ct_limit_genl_ops[] = { + { .cmd = OVS_CT_LIMIT_CMD_SET, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, + .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN + * privilege. + */ + .doit = ovs_ct_limit_cmd_set, + }, + { .cmd = OVS_CT_LIMIT_CMD_DEL, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, + .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN + * privilege. + */ + .doit = ovs_ct_limit_cmd_del, + }, + { .cmd = OVS_CT_LIMIT_CMD_GET, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, + .flags = 0, /* OK for unprivileged users. */ + .doit = ovs_ct_limit_cmd_get, + }, +}; + +static const struct genl_multicast_group ovs_ct_limit_multicast_group = { + .name = OVS_CT_LIMIT_MCGROUP, +}; + +struct genl_family dp_ct_limit_genl_family __ro_after_init = { + .hdrsize = sizeof(struct ovs_header), + .name = OVS_CT_LIMIT_FAMILY, + .version = OVS_CT_LIMIT_VERSION, + .maxattr = OVS_CT_LIMIT_ATTR_MAX, + .policy = ct_limit_policy, + .netnsok = true, + .parallel_ops = true, + .small_ops = ct_limit_genl_ops, + .n_small_ops = ARRAY_SIZE(ct_limit_genl_ops), + .resv_start_op = OVS_CT_LIMIT_CMD_GET + 1, + .mcgrps = &ovs_ct_limit_multicast_group, + .n_mcgrps = 1, + .module = THIS_MODULE, +}; +#endif + +int 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; + } + +#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) + return ovs_ct_limit_init(net, ovs_net); +#else + return 0; +#endif +} + +void ovs_ct_exit(struct net *net) +{ + struct ovs_net *ovs_net = net_generic(net, ovs_net_id); + +#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) + ovs_ct_limit_exit(net, ovs_net); +#endif + + if (ovs_net->xt_label) + nf_connlabels_put(net); +} |