From 9c26ba9b1f453a0c86b26e9ab5e8efedcb4470d8 Mon Sep 17 00:00:00 2001 From: Paul Blakey Date: Thu, 12 Mar 2020 12:23:06 +0200 Subject: net/sched: act_ct: Instantiate flow table entry actions NF flow table API associate 5-tuple rule with an action list by calling the flow table type action() CB to fill the rule's actions. In action CB of act_ct, populate the ct offload entry actions with a new ct_metadata action. Initialize the ct_metadata with the ct mark, label and zone information. If ct nat was performed, then also append the relevant packet mangle actions (e.g. ipv4/ipv6/tcp/udp header rewrites). Drivers that offload the ft entries may match on the 5-tuple and perform the action list. Signed-off-by: Paul Blakey Reviewed-by: Jiri Pirko Reviewed-by: Edward Cree Signed-off-by: David S. Miller --- net/sched/act_ct.c | 207 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 207 insertions(+) (limited to 'net/sched') diff --git a/net/sched/act_ct.c b/net/sched/act_ct.c index 3d9e678d7d53..9c522bc51f68 100644 --- a/net/sched/act_ct.c +++ b/net/sched/act_ct.c @@ -55,7 +55,214 @@ static const struct rhashtable_params zones_params = { .automatic_shrinking = true, }; +static struct flow_action_entry * +tcf_ct_flow_table_flow_action_get_next(struct flow_action *flow_action) +{ + int i = flow_action->num_entries++; + + return &flow_action->entries[i]; +} + +static void tcf_ct_add_mangle_action(struct flow_action *action, + enum flow_action_mangle_base htype, + u32 offset, + u32 mask, + u32 val) +{ + struct flow_action_entry *entry; + + entry = tcf_ct_flow_table_flow_action_get_next(action); + entry->id = FLOW_ACTION_MANGLE; + entry->mangle.htype = htype; + entry->mangle.mask = ~mask; + entry->mangle.offset = offset; + entry->mangle.val = val; +} + +/* The following nat helper functions check if the inverted reverse tuple + * (target) is different then the current dir tuple - meaning nat for ports + * and/or ip is needed, and add the relevant mangle actions. + */ +static void +tcf_ct_flow_table_add_action_nat_ipv4(const struct nf_conntrack_tuple *tuple, + struct nf_conntrack_tuple target, + struct flow_action *action) +{ + if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3))) + tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4, + offsetof(struct iphdr, saddr), + 0xFFFFFFFF, + be32_to_cpu(target.src.u3.ip)); + if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3))) + tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4, + offsetof(struct iphdr, daddr), + 0xFFFFFFFF, + be32_to_cpu(target.dst.u3.ip)); +} + +static void +tcf_ct_add_ipv6_addr_mangle_action(struct flow_action *action, + union nf_inet_addr *addr, + u32 offset) +{ + int i; + + for (i = 0; i < sizeof(struct in6_addr) / sizeof(u32); i++) + tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP6, + i * sizeof(u32) + offset, + 0xFFFFFFFF, be32_to_cpu(addr->ip6[i])); +} + +static void +tcf_ct_flow_table_add_action_nat_ipv6(const struct nf_conntrack_tuple *tuple, + struct nf_conntrack_tuple target, + struct flow_action *action) +{ + if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3))) + tcf_ct_add_ipv6_addr_mangle_action(action, &target.src.u3, + offsetof(struct ipv6hdr, + saddr)); + if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3))) + tcf_ct_add_ipv6_addr_mangle_action(action, &target.dst.u3, + offsetof(struct ipv6hdr, + daddr)); +} + +static void +tcf_ct_flow_table_add_action_nat_tcp(const struct nf_conntrack_tuple *tuple, + struct nf_conntrack_tuple target, + struct flow_action *action) +{ + __be16 target_src = target.src.u.tcp.port; + __be16 target_dst = target.dst.u.tcp.port; + + if (target_src != tuple->src.u.tcp.port) + tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP, + offsetof(struct tcphdr, source), + 0xFFFF, be16_to_cpu(target_src)); + if (target_dst != tuple->dst.u.tcp.port) + tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP, + offsetof(struct tcphdr, dest), + 0xFFFF, be16_to_cpu(target_dst)); +} + +static void +tcf_ct_flow_table_add_action_nat_udp(const struct nf_conntrack_tuple *tuple, + struct nf_conntrack_tuple target, + struct flow_action *action) +{ + __be16 target_src = target.src.u.udp.port; + __be16 target_dst = target.dst.u.udp.port; + + if (target_src != tuple->src.u.udp.port) + tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP, + offsetof(struct udphdr, source), + 0xFFFF, be16_to_cpu(target_src)); + if (target_dst != tuple->dst.u.udp.port) + tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP, + offsetof(struct udphdr, dest), + 0xFFFF, be16_to_cpu(target_dst)); +} + +static void tcf_ct_flow_table_add_action_meta(struct nf_conn *ct, + enum ip_conntrack_dir dir, + struct flow_action *action) +{ + struct nf_conn_labels *ct_labels; + struct flow_action_entry *entry; + u32 *act_ct_labels; + + entry = tcf_ct_flow_table_flow_action_get_next(action); + entry->id = FLOW_ACTION_CT_METADATA; +#if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) + entry->ct_metadata.mark = ct->mark; +#endif + + act_ct_labels = entry->ct_metadata.labels; + ct_labels = nf_ct_labels_find(ct); + if (ct_labels) + memcpy(act_ct_labels, ct_labels->bits, NF_CT_LABELS_MAX_SIZE); + else + memset(act_ct_labels, 0, NF_CT_LABELS_MAX_SIZE); +} + +static int tcf_ct_flow_table_add_action_nat(struct net *net, + struct nf_conn *ct, + enum ip_conntrack_dir dir, + struct flow_action *action) +{ + const struct nf_conntrack_tuple *tuple = &ct->tuplehash[dir].tuple; + struct nf_conntrack_tuple target; + + nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple); + + switch (tuple->src.l3num) { + case NFPROTO_IPV4: + tcf_ct_flow_table_add_action_nat_ipv4(tuple, target, + action); + break; + case NFPROTO_IPV6: + tcf_ct_flow_table_add_action_nat_ipv6(tuple, target, + action); + break; + default: + return -EOPNOTSUPP; + } + + switch (nf_ct_protonum(ct)) { + case IPPROTO_TCP: + tcf_ct_flow_table_add_action_nat_tcp(tuple, target, action); + break; + case IPPROTO_UDP: + tcf_ct_flow_table_add_action_nat_udp(tuple, target, action); + break; + default: + return -EOPNOTSUPP; + } + + return 0; +} + +static int tcf_ct_flow_table_fill_actions(struct net *net, + const struct flow_offload *flow, + enum flow_offload_tuple_dir tdir, + struct nf_flow_rule *flow_rule) +{ + struct flow_action *action = &flow_rule->rule->action; + int num_entries = action->num_entries; + struct nf_conn *ct = flow->ct; + enum ip_conntrack_dir dir; + int i, err; + + switch (tdir) { + case FLOW_OFFLOAD_DIR_ORIGINAL: + dir = IP_CT_DIR_ORIGINAL; + break; + case FLOW_OFFLOAD_DIR_REPLY: + dir = IP_CT_DIR_REPLY; + break; + default: + return -EOPNOTSUPP; + } + + err = tcf_ct_flow_table_add_action_nat(net, ct, dir, action); + if (err) + goto err_nat; + + tcf_ct_flow_table_add_action_meta(ct, dir, action); + return 0; + +err_nat: + /* Clear filled actions */ + for (i = num_entries; i < action->num_entries; i++) + memset(&action->entries[i], 0, sizeof(action->entries[i])); + action->num_entries = num_entries; + + return err; +} + static struct nf_flowtable_type flowtable_ct = { + .action = tcf_ct_flow_table_fill_actions, .owner = THIS_MODULE, }; -- cgit v1.2.3