1632 строки
44 KiB
C
1632 строки
44 KiB
C
/*
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* Copyright (c) 2015 Nicira, Inc.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of version 2 of the GNU General Public
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* License as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*/
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#include <linux/module.h>
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#include <linux/openvswitch.h>
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#include <linux/tcp.h>
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#include <linux/udp.h>
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#include <linux/sctp.h>
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#include <net/ip.h>
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#include <net/netfilter/nf_conntrack_core.h>
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#include <net/netfilter/nf_conntrack_helper.h>
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#include <net/netfilter/nf_conntrack_labels.h>
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#include <net/netfilter/nf_conntrack_seqadj.h>
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#include <net/netfilter/nf_conntrack_zones.h>
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#include <net/netfilter/ipv6/nf_defrag_ipv6.h>
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#ifdef CONFIG_NF_NAT_NEEDED
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#include <linux/netfilter/nf_nat.h>
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#include <net/netfilter/nf_nat_core.h>
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#include <net/netfilter/nf_nat_l3proto.h>
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#endif
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#include "datapath.h"
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#include "conntrack.h"
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#include "flow.h"
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#include "flow_netlink.h"
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struct ovs_ct_len_tbl {
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int maxlen;
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int minlen;
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};
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/* Metadata mark for masked write to conntrack mark */
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struct md_mark {
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u32 value;
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u32 mask;
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};
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/* Metadata label for masked write to conntrack label. */
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struct md_labels {
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struct ovs_key_ct_labels value;
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struct ovs_key_ct_labels mask;
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};
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enum ovs_ct_nat {
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OVS_CT_NAT = 1 << 0, /* NAT for committed connections only. */
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OVS_CT_SRC_NAT = 1 << 1, /* Source NAT for NEW connections. */
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OVS_CT_DST_NAT = 1 << 2, /* Destination NAT for NEW connections. */
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};
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/* Conntrack action context for execution. */
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struct ovs_conntrack_info {
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struct nf_conntrack_helper *helper;
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struct nf_conntrack_zone zone;
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struct nf_conn *ct;
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u8 commit : 1;
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u8 nat : 3; /* enum ovs_ct_nat */
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u8 force : 1;
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u8 have_eventmask : 1;
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u16 family;
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u32 eventmask; /* Mask of 1 << IPCT_*. */
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struct md_mark mark;
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struct md_labels labels;
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#ifdef CONFIG_NF_NAT_NEEDED
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struct nf_nat_range range; /* Only present for SRC NAT and DST NAT. */
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#endif
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};
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static bool labels_nonzero(const struct ovs_key_ct_labels *labels);
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static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info);
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static u16 key_to_nfproto(const struct sw_flow_key *key)
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{
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switch (ntohs(key->eth.type)) {
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case ETH_P_IP:
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return NFPROTO_IPV4;
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case ETH_P_IPV6:
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return NFPROTO_IPV6;
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default:
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return NFPROTO_UNSPEC;
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}
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}
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/* Map SKB connection state into the values used by flow definition. */
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static u8 ovs_ct_get_state(enum ip_conntrack_info ctinfo)
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{
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u8 ct_state = OVS_CS_F_TRACKED;
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switch (ctinfo) {
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case IP_CT_ESTABLISHED_REPLY:
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case IP_CT_RELATED_REPLY:
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ct_state |= OVS_CS_F_REPLY_DIR;
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break;
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default:
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break;
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}
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switch (ctinfo) {
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case IP_CT_ESTABLISHED:
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case IP_CT_ESTABLISHED_REPLY:
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ct_state |= OVS_CS_F_ESTABLISHED;
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break;
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case IP_CT_RELATED:
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case IP_CT_RELATED_REPLY:
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ct_state |= OVS_CS_F_RELATED;
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break;
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case IP_CT_NEW:
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ct_state |= OVS_CS_F_NEW;
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break;
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default:
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break;
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}
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return ct_state;
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}
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static u32 ovs_ct_get_mark(const struct nf_conn *ct)
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{
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#if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
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return ct ? ct->mark : 0;
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#else
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return 0;
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#endif
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}
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/* Guard against conntrack labels max size shrinking below 128 bits. */
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#if NF_CT_LABELS_MAX_SIZE < 16
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#error NF_CT_LABELS_MAX_SIZE must be at least 16 bytes
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#endif
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static void ovs_ct_get_labels(const struct nf_conn *ct,
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struct ovs_key_ct_labels *labels)
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{
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struct nf_conn_labels *cl = ct ? nf_ct_labels_find(ct) : NULL;
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if (cl)
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memcpy(labels, cl->bits, OVS_CT_LABELS_LEN);
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else
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memset(labels, 0, OVS_CT_LABELS_LEN);
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}
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static void __ovs_ct_update_key_orig_tp(struct sw_flow_key *key,
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const struct nf_conntrack_tuple *orig,
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u8 icmp_proto)
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{
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key->ct_orig_proto = orig->dst.protonum;
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if (orig->dst.protonum == icmp_proto) {
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key->ct.orig_tp.src = htons(orig->dst.u.icmp.type);
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key->ct.orig_tp.dst = htons(orig->dst.u.icmp.code);
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} else {
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key->ct.orig_tp.src = orig->src.u.all;
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key->ct.orig_tp.dst = orig->dst.u.all;
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}
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}
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static void __ovs_ct_update_key(struct sw_flow_key *key, u8 state,
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const struct nf_conntrack_zone *zone,
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const struct nf_conn *ct)
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{
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key->ct_state = state;
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key->ct_zone = zone->id;
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key->ct.mark = ovs_ct_get_mark(ct);
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ovs_ct_get_labels(ct, &key->ct.labels);
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if (ct) {
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const struct nf_conntrack_tuple *orig;
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/* Use the master if we have one. */
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if (ct->master)
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ct = ct->master;
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orig = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
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/* IP version must match with the master connection. */
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if (key->eth.type == htons(ETH_P_IP) &&
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nf_ct_l3num(ct) == NFPROTO_IPV4) {
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key->ipv4.ct_orig.src = orig->src.u3.ip;
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key->ipv4.ct_orig.dst = orig->dst.u3.ip;
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__ovs_ct_update_key_orig_tp(key, orig, IPPROTO_ICMP);
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return;
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} else if (key->eth.type == htons(ETH_P_IPV6) &&
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!sw_flow_key_is_nd(key) &&
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nf_ct_l3num(ct) == NFPROTO_IPV6) {
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key->ipv6.ct_orig.src = orig->src.u3.in6;
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key->ipv6.ct_orig.dst = orig->dst.u3.in6;
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__ovs_ct_update_key_orig_tp(key, orig, NEXTHDR_ICMP);
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return;
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}
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}
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/* Clear 'ct_orig_proto' to mark the non-existence of conntrack
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* original direction key fields.
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*/
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key->ct_orig_proto = 0;
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}
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/* Update 'key' based on skb->_nfct. If 'post_ct' is true, then OVS has
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* previously sent the packet to conntrack via the ct action. If
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* 'keep_nat_flags' is true, the existing NAT flags retained, else they are
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* initialized from the connection status.
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*/
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static void ovs_ct_update_key(const struct sk_buff *skb,
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const struct ovs_conntrack_info *info,
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struct sw_flow_key *key, bool post_ct,
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bool keep_nat_flags)
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{
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const struct nf_conntrack_zone *zone = &nf_ct_zone_dflt;
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enum ip_conntrack_info ctinfo;
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struct nf_conn *ct;
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u8 state = 0;
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ct = nf_ct_get(skb, &ctinfo);
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if (ct) {
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state = ovs_ct_get_state(ctinfo);
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/* All unconfirmed entries are NEW connections. */
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if (!nf_ct_is_confirmed(ct))
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state |= OVS_CS_F_NEW;
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/* OVS persists the related flag for the duration of the
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* connection.
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*/
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if (ct->master)
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state |= OVS_CS_F_RELATED;
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if (keep_nat_flags) {
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state |= key->ct_state & OVS_CS_F_NAT_MASK;
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} else {
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if (ct->status & IPS_SRC_NAT)
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state |= OVS_CS_F_SRC_NAT;
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if (ct->status & IPS_DST_NAT)
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state |= OVS_CS_F_DST_NAT;
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}
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zone = nf_ct_zone(ct);
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} else if (post_ct) {
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state = OVS_CS_F_TRACKED | OVS_CS_F_INVALID;
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if (info)
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zone = &info->zone;
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}
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__ovs_ct_update_key(key, state, zone, ct);
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}
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/* This is called to initialize CT key fields possibly coming in from the local
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* stack.
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*/
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void ovs_ct_fill_key(const struct sk_buff *skb, struct sw_flow_key *key)
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{
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ovs_ct_update_key(skb, NULL, key, false, false);
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}
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#define IN6_ADDR_INITIALIZER(ADDR) \
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{ (ADDR).s6_addr32[0], (ADDR).s6_addr32[1], \
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(ADDR).s6_addr32[2], (ADDR).s6_addr32[3] }
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int ovs_ct_put_key(const struct sw_flow_key *swkey,
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const struct sw_flow_key *output, struct sk_buff *skb)
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{
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if (nla_put_u32(skb, OVS_KEY_ATTR_CT_STATE, output->ct_state))
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return -EMSGSIZE;
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if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
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nla_put_u16(skb, OVS_KEY_ATTR_CT_ZONE, output->ct_zone))
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return -EMSGSIZE;
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if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
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nla_put_u32(skb, OVS_KEY_ATTR_CT_MARK, output->ct.mark))
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return -EMSGSIZE;
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if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
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nla_put(skb, OVS_KEY_ATTR_CT_LABELS, sizeof(output->ct.labels),
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&output->ct.labels))
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return -EMSGSIZE;
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if (swkey->ct_orig_proto) {
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if (swkey->eth.type == htons(ETH_P_IP)) {
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struct ovs_key_ct_tuple_ipv4 orig = {
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output->ipv4.ct_orig.src,
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output->ipv4.ct_orig.dst,
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output->ct.orig_tp.src,
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output->ct.orig_tp.dst,
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output->ct_orig_proto,
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};
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if (nla_put(skb, OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4,
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sizeof(orig), &orig))
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return -EMSGSIZE;
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} else if (swkey->eth.type == htons(ETH_P_IPV6)) {
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struct ovs_key_ct_tuple_ipv6 orig = {
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IN6_ADDR_INITIALIZER(output->ipv6.ct_orig.src),
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IN6_ADDR_INITIALIZER(output->ipv6.ct_orig.dst),
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output->ct.orig_tp.src,
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output->ct.orig_tp.dst,
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output->ct_orig_proto,
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};
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if (nla_put(skb, OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6,
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sizeof(orig), &orig))
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return -EMSGSIZE;
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}
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}
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return 0;
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}
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static int ovs_ct_set_mark(struct nf_conn *ct, struct sw_flow_key *key,
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u32 ct_mark, u32 mask)
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{
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#if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
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u32 new_mark;
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new_mark = ct_mark | (ct->mark & ~(mask));
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if (ct->mark != new_mark) {
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ct->mark = new_mark;
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if (nf_ct_is_confirmed(ct))
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nf_conntrack_event_cache(IPCT_MARK, ct);
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key->ct.mark = new_mark;
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}
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return 0;
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#else
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return -ENOTSUPP;
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#endif
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}
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static struct nf_conn_labels *ovs_ct_get_conn_labels(struct nf_conn *ct)
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{
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struct nf_conn_labels *cl;
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cl = nf_ct_labels_find(ct);
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if (!cl) {
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nf_ct_labels_ext_add(ct);
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cl = nf_ct_labels_find(ct);
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}
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return cl;
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}
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/* Initialize labels for a new, yet to be committed conntrack entry. Note that
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* since the new connection is not yet confirmed, and thus no-one else has
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* access to it's labels, we simply write them over.
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*/
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static int ovs_ct_init_labels(struct nf_conn *ct, struct sw_flow_key *key,
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const struct ovs_key_ct_labels *labels,
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const struct ovs_key_ct_labels *mask)
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{
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struct nf_conn_labels *cl, *master_cl;
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bool have_mask = labels_nonzero(mask);
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/* Inherit master's labels to the related connection? */
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master_cl = ct->master ? nf_ct_labels_find(ct->master) : NULL;
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if (!master_cl && !have_mask)
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return 0; /* Nothing to do. */
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cl = ovs_ct_get_conn_labels(ct);
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if (!cl)
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return -ENOSPC;
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/* Inherit the master's labels, if any. */
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if (master_cl)
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*cl = *master_cl;
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if (have_mask) {
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u32 *dst = (u32 *)cl->bits;
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int i;
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for (i = 0; i < OVS_CT_LABELS_LEN_32; i++)
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dst[i] = (dst[i] & ~mask->ct_labels_32[i]) |
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(labels->ct_labels_32[i]
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& mask->ct_labels_32[i]);
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}
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/* Labels are included in the IPCTNL_MSG_CT_NEW event only if the
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* IPCT_LABEL bit is set in the event cache.
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*/
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nf_conntrack_event_cache(IPCT_LABEL, ct);
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memcpy(&key->ct.labels, cl->bits, OVS_CT_LABELS_LEN);
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return 0;
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}
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static int ovs_ct_set_labels(struct nf_conn *ct, struct sw_flow_key *key,
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const struct ovs_key_ct_labels *labels,
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const struct ovs_key_ct_labels *mask)
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{
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struct nf_conn_labels *cl;
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int err;
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cl = ovs_ct_get_conn_labels(ct);
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if (!cl)
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return -ENOSPC;
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err = nf_connlabels_replace(ct, labels->ct_labels_32,
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mask->ct_labels_32,
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OVS_CT_LABELS_LEN_32);
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if (err)
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return err;
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memcpy(&key->ct.labels, cl->bits, OVS_CT_LABELS_LEN);
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return 0;
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}
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/* 'skb' should already be pulled to nh_ofs. */
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static int ovs_ct_helper(struct sk_buff *skb, u16 proto)
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{
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const struct nf_conntrack_helper *helper;
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const struct nf_conn_help *help;
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enum ip_conntrack_info ctinfo;
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unsigned int protoff;
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struct nf_conn *ct;
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int err;
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ct = nf_ct_get(skb, &ctinfo);
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if (!ct || ctinfo == IP_CT_RELATED_REPLY)
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return NF_ACCEPT;
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help = nfct_help(ct);
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if (!help)
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return NF_ACCEPT;
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helper = rcu_dereference(help->helper);
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if (!helper)
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return NF_ACCEPT;
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switch (proto) {
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case NFPROTO_IPV4:
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protoff = ip_hdrlen(skb);
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break;
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case NFPROTO_IPV6: {
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u8 nexthdr = ipv6_hdr(skb)->nexthdr;
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__be16 frag_off;
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int ofs;
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ofs = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr,
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&frag_off);
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if (ofs < 0 || (frag_off & htons(~0x7)) != 0) {
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pr_debug("proto header not found\n");
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return NF_ACCEPT;
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}
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protoff = ofs;
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break;
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}
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default:
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WARN_ONCE(1, "helper invoked on non-IP family!");
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return NF_DROP;
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}
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err = helper->help(skb, protoff, ct, ctinfo);
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if (err != NF_ACCEPT)
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return err;
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/* Adjust seqs after helper. This is needed due to some helpers (e.g.,
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* FTP with NAT) adusting the TCP payload size when mangling IP
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* addresses and/or port numbers in the text-based control connection.
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*/
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if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
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!nf_ct_seq_adjust(skb, ct, ctinfo, protoff))
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return NF_DROP;
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return NF_ACCEPT;
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}
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/* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero
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* value if 'skb' is freed.
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*/
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static int handle_fragments(struct net *net, struct sw_flow_key *key,
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u16 zone, struct sk_buff *skb)
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{
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struct ovs_skb_cb ovs_cb = *OVS_CB(skb);
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int err;
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if (key->eth.type == htons(ETH_P_IP)) {
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enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone;
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memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
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err = ip_defrag(net, skb, user);
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if (err)
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return err;
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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);
|
|
|
|
/* 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 (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);
|
|
|
|
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);
|
|
}
|