1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (c) 2015 Nicira, Inc.
   4 */
   5
   6#include <linux/module.h>
   7#include <linux/openvswitch.h>
   8#include <linux/tcp.h>
   9#include <linux/udp.h>
  10#include <linux/sctp.h>
  11#include <linux/static_key.h>
 
  12#include <net/ip.h>
  13#include <net/genetlink.h>
  14#include <net/netfilter/nf_conntrack_core.h>
  15#include <net/netfilter/nf_conntrack_count.h>
  16#include <net/netfilter/nf_conntrack_helper.h>
  17#include <net/netfilter/nf_conntrack_labels.h>
  18#include <net/netfilter/nf_conntrack_seqadj.h>
  19#include <net/netfilter/nf_conntrack_timeout.h>
  20#include <net/netfilter/nf_conntrack_zones.h>
  21#include <net/netfilter/ipv6/nf_defrag_ipv6.h>
  22#include <net/ipv6_frag.h>
  23
  24#if IS_ENABLED(CONFIG_NF_NAT)
  25#include <net/netfilter/nf_nat.h>
  26#endif
  27
 
 
  28#include "datapath.h"
 
  29#include "conntrack.h"
  30#include "flow.h"
  31#include "flow_netlink.h"
  32
  33struct ovs_ct_len_tbl {
  34	int maxlen;
  35	int minlen;
  36};
  37
  38/* Metadata mark for masked write to conntrack mark */
  39struct md_mark {
  40	u32 value;
  41	u32 mask;
  42};
  43
  44/* Metadata label for masked write to conntrack label. */
  45struct md_labels {
  46	struct ovs_key_ct_labels value;
  47	struct ovs_key_ct_labels mask;
  48};
  49
  50enum ovs_ct_nat {
  51	OVS_CT_NAT = 1 << 0,     /* NAT for committed connections only. */
  52	OVS_CT_SRC_NAT = 1 << 1, /* Source NAT for NEW connections. */
  53	OVS_CT_DST_NAT = 1 << 2, /* Destination NAT for NEW connections. */
  54};
  55
  56/* Conntrack action context for execution. */
  57struct ovs_conntrack_info {
  58	struct nf_conntrack_helper *helper;
  59	struct nf_conntrack_zone zone;
  60	struct nf_conn *ct;
  61	u8 commit : 1;
  62	u8 nat : 3;                 /* enum ovs_ct_nat */
  63	u8 force : 1;
  64	u8 have_eventmask : 1;
  65	u16 family;
  66	u32 eventmask;              /* Mask of 1 << IPCT_*. */
  67	struct md_mark mark;
  68	struct md_labels labels;
  69	char timeout[CTNL_TIMEOUT_NAME_MAX];
  70	struct nf_ct_timeout *nf_ct_timeout;
  71#if IS_ENABLED(CONFIG_NF_NAT)
  72	struct nf_nat_range2 range;  /* Only present for SRC NAT and DST NAT. */
  73#endif
  74};
  75
  76#if	IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
  77#define OVS_CT_LIMIT_UNLIMITED	0
  78#define OVS_CT_LIMIT_DEFAULT OVS_CT_LIMIT_UNLIMITED
  79#define CT_LIMIT_HASH_BUCKETS 512
  80static DEFINE_STATIC_KEY_FALSE(ovs_ct_limit_enabled);
  81
  82struct ovs_ct_limit {
  83	/* Elements in ovs_ct_limit_info->limits hash table */
  84	struct hlist_node hlist_node;
  85	struct rcu_head rcu;
  86	u16 zone;
  87	u32 limit;
  88};
  89
  90struct ovs_ct_limit_info {
  91	u32 default_limit;
  92	struct hlist_head *limits;
  93	struct nf_conncount_data *data;
  94};
  95
  96static const struct nla_policy ct_limit_policy[OVS_CT_LIMIT_ATTR_MAX + 1] = {
  97	[OVS_CT_LIMIT_ATTR_ZONE_LIMIT] = { .type = NLA_NESTED, },
  98};
  99#endif
 100
 101static bool labels_nonzero(const struct ovs_key_ct_labels *labels);
 102
 103static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info);
 104
 105static u16 key_to_nfproto(const struct sw_flow_key *key)
 106{
 107	switch (ntohs(key->eth.type)) {
 108	case ETH_P_IP:
 109		return NFPROTO_IPV4;
 110	case ETH_P_IPV6:
 111		return NFPROTO_IPV6;
 112	default:
 113		return NFPROTO_UNSPEC;
 114	}
 115}
 116
 117/* Map SKB connection state into the values used by flow definition. */
 118static u8 ovs_ct_get_state(enum ip_conntrack_info ctinfo)
 119{
 120	u8 ct_state = OVS_CS_F_TRACKED;
 121
 122	switch (ctinfo) {
 123	case IP_CT_ESTABLISHED_REPLY:
 124	case IP_CT_RELATED_REPLY:
 125		ct_state |= OVS_CS_F_REPLY_DIR;
 126		break;
 127	default:
 128		break;
 129	}
 130
 131	switch (ctinfo) {
 132	case IP_CT_ESTABLISHED:
 133	case IP_CT_ESTABLISHED_REPLY:
 134		ct_state |= OVS_CS_F_ESTABLISHED;
 135		break;
 136	case IP_CT_RELATED:
 137	case IP_CT_RELATED_REPLY:
 138		ct_state |= OVS_CS_F_RELATED;
 139		break;
 140	case IP_CT_NEW:
 141		ct_state |= OVS_CS_F_NEW;
 142		break;
 143	default:
 144		break;
 145	}
 146
 147	return ct_state;
 148}
 149
 150static u32 ovs_ct_get_mark(const struct nf_conn *ct)
 151{
 152#if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
 153	return ct ? ct->mark : 0;
 154#else
 155	return 0;
 156#endif
 157}
 158
 159/* Guard against conntrack labels max size shrinking below 128 bits. */
 160#if NF_CT_LABELS_MAX_SIZE < 16
 161#error NF_CT_LABELS_MAX_SIZE must be at least 16 bytes
 162#endif
 163
 164static void ovs_ct_get_labels(const struct nf_conn *ct,
 165			      struct ovs_key_ct_labels *labels)
 166{
 167	struct nf_conn_labels *cl = ct ? nf_ct_labels_find(ct) : NULL;
 168
 
 
 
 
 
 169	if (cl)
 170		memcpy(labels, cl->bits, OVS_CT_LABELS_LEN);
 171	else
 172		memset(labels, 0, OVS_CT_LABELS_LEN);
 173}
 174
 175static void __ovs_ct_update_key_orig_tp(struct sw_flow_key *key,
 176					const struct nf_conntrack_tuple *orig,
 177					u8 icmp_proto)
 178{
 179	key->ct_orig_proto = orig->dst.protonum;
 180	if (orig->dst.protonum == icmp_proto) {
 181		key->ct.orig_tp.src = htons(orig->dst.u.icmp.type);
 182		key->ct.orig_tp.dst = htons(orig->dst.u.icmp.code);
 183	} else {
 184		key->ct.orig_tp.src = orig->src.u.all;
 185		key->ct.orig_tp.dst = orig->dst.u.all;
 186	}
 187}
 188
 189static void __ovs_ct_update_key(struct sw_flow_key *key, u8 state,
 190				const struct nf_conntrack_zone *zone,
 191				const struct nf_conn *ct)
 192{
 193	key->ct_state = state;
 194	key->ct_zone = zone->id;
 195	key->ct.mark = ovs_ct_get_mark(ct);
 196	ovs_ct_get_labels(ct, &key->ct.labels);
 197
 198	if (ct) {
 199		const struct nf_conntrack_tuple *orig;
 200
 201		/* Use the master if we have one. */
 202		if (ct->master)
 203			ct = ct->master;
 204		orig = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
 205
 206		/* IP version must match with the master connection. */
 207		if (key->eth.type == htons(ETH_P_IP) &&
 208		    nf_ct_l3num(ct) == NFPROTO_IPV4) {
 209			key->ipv4.ct_orig.src = orig->src.u3.ip;
 210			key->ipv4.ct_orig.dst = orig->dst.u3.ip;
 211			__ovs_ct_update_key_orig_tp(key, orig, IPPROTO_ICMP);
 212			return;
 213		} else if (key->eth.type == htons(ETH_P_IPV6) &&
 214			   !sw_flow_key_is_nd(key) &&
 215			   nf_ct_l3num(ct) == NFPROTO_IPV6) {
 216			key->ipv6.ct_orig.src = orig->src.u3.in6;
 217			key->ipv6.ct_orig.dst = orig->dst.u3.in6;
 218			__ovs_ct_update_key_orig_tp(key, orig, NEXTHDR_ICMP);
 219			return;
 220		}
 221	}
 222	/* Clear 'ct_orig_proto' to mark the non-existence of conntrack
 223	 * original direction key fields.
 224	 */
 225	key->ct_orig_proto = 0;
 226}
 227
 228/* Update 'key' based on skb->_nfct.  If 'post_ct' is true, then OVS has
 229 * previously sent the packet to conntrack via the ct action.  If
 230 * 'keep_nat_flags' is true, the existing NAT flags retained, else they are
 231 * initialized from the connection status.
 232 */
 233static void ovs_ct_update_key(const struct sk_buff *skb,
 234			      const struct ovs_conntrack_info *info,
 235			      struct sw_flow_key *key, bool post_ct,
 236			      bool keep_nat_flags)
 237{
 238	const struct nf_conntrack_zone *zone = &nf_ct_zone_dflt;
 239	enum ip_conntrack_info ctinfo;
 240	struct nf_conn *ct;
 241	u8 state = 0;
 242
 243	ct = nf_ct_get(skb, &ctinfo);
 244	if (ct) {
 245		state = ovs_ct_get_state(ctinfo);
 246		/* All unconfirmed entries are NEW connections. */
 247		if (!nf_ct_is_confirmed(ct))
 248			state |= OVS_CS_F_NEW;
 249		/* OVS persists the related flag for the duration of the
 250		 * connection.
 251		 */
 252		if (ct->master)
 253			state |= OVS_CS_F_RELATED;
 254		if (keep_nat_flags) {
 255			state |= key->ct_state & OVS_CS_F_NAT_MASK;
 256		} else {
 257			if (ct->status & IPS_SRC_NAT)
 258				state |= OVS_CS_F_SRC_NAT;
 259			if (ct->status & IPS_DST_NAT)
 260				state |= OVS_CS_F_DST_NAT;
 261		}
 262		zone = nf_ct_zone(ct);
 263	} else if (post_ct) {
 264		state = OVS_CS_F_TRACKED | OVS_CS_F_INVALID;
 265		if (info)
 266			zone = &info->zone;
 267	}
 268	__ovs_ct_update_key(key, state, zone, ct);
 269}
 270
 271/* This is called to initialize CT key fields possibly coming in from the local
 272 * stack.
 273 */
 274void ovs_ct_fill_key(const struct sk_buff *skb, struct sw_flow_key *key)
 
 
 275{
 276	ovs_ct_update_key(skb, NULL, key, false, false);
 277}
 278
 279#define IN6_ADDR_INITIALIZER(ADDR) \
 280	{ (ADDR).s6_addr32[0], (ADDR).s6_addr32[1], \
 281	  (ADDR).s6_addr32[2], (ADDR).s6_addr32[3] }
 282
 283int ovs_ct_put_key(const struct sw_flow_key *swkey,
 284		   const struct sw_flow_key *output, struct sk_buff *skb)
 285{
 286	if (nla_put_u32(skb, OVS_KEY_ATTR_CT_STATE, output->ct_state))
 287		return -EMSGSIZE;
 288
 289	if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
 290	    nla_put_u16(skb, OVS_KEY_ATTR_CT_ZONE, output->ct_zone))
 291		return -EMSGSIZE;
 292
 293	if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
 294	    nla_put_u32(skb, OVS_KEY_ATTR_CT_MARK, output->ct.mark))
 295		return -EMSGSIZE;
 296
 297	if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
 298	    nla_put(skb, OVS_KEY_ATTR_CT_LABELS, sizeof(output->ct.labels),
 299		    &output->ct.labels))
 300		return -EMSGSIZE;
 301
 302	if (swkey->ct_orig_proto) {
 303		if (swkey->eth.type == htons(ETH_P_IP)) {
 304			struct ovs_key_ct_tuple_ipv4 orig = {
 305				output->ipv4.ct_orig.src,
 306				output->ipv4.ct_orig.dst,
 307				output->ct.orig_tp.src,
 308				output->ct.orig_tp.dst,
 309				output->ct_orig_proto,
 310			};
 
 
 311			if (nla_put(skb, OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4,
 312				    sizeof(orig), &orig))
 313				return -EMSGSIZE;
 314		} else if (swkey->eth.type == htons(ETH_P_IPV6)) {
 315			struct ovs_key_ct_tuple_ipv6 orig = {
 316				IN6_ADDR_INITIALIZER(output->ipv6.ct_orig.src),
 317				IN6_ADDR_INITIALIZER(output->ipv6.ct_orig.dst),
 318				output->ct.orig_tp.src,
 319				output->ct.orig_tp.dst,
 320				output->ct_orig_proto,
 321			};
 
 
 
 
 322			if (nla_put(skb, OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6,
 323				    sizeof(orig), &orig))
 324				return -EMSGSIZE;
 325		}
 326	}
 327
 328	return 0;
 329}
 330
 331static int ovs_ct_set_mark(struct nf_conn *ct, struct sw_flow_key *key,
 332			   u32 ct_mark, u32 mask)
 333{
 334#if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
 335	u32 new_mark;
 336
 337	new_mark = ct_mark | (ct->mark & ~(mask));
 338	if (ct->mark != new_mark) {
 339		ct->mark = new_mark;
 340		if (nf_ct_is_confirmed(ct))
 341			nf_conntrack_event_cache(IPCT_MARK, ct);
 342		key->ct.mark = new_mark;
 343	}
 344
 345	return 0;
 346#else
 347	return -ENOTSUPP;
 348#endif
 349}
 350
 351static struct nf_conn_labels *ovs_ct_get_conn_labels(struct nf_conn *ct)
 352{
 353	struct nf_conn_labels *cl;
 354
 355	cl = nf_ct_labels_find(ct);
 356	if (!cl) {
 357		nf_ct_labels_ext_add(ct);
 358		cl = nf_ct_labels_find(ct);
 359	}
 360
 361	return cl;
 362}
 363
 364/* Initialize labels for a new, yet to be committed conntrack entry.  Note that
 365 * since the new connection is not yet confirmed, and thus no-one else has
 366 * access to it's labels, we simply write them over.
 367 */
 368static int ovs_ct_init_labels(struct nf_conn *ct, struct sw_flow_key *key,
 369			      const struct ovs_key_ct_labels *labels,
 370			      const struct ovs_key_ct_labels *mask)
 371{
 372	struct nf_conn_labels *cl, *master_cl;
 373	bool have_mask = labels_nonzero(mask);
 374
 375	/* Inherit master's labels to the related connection? */
 376	master_cl = ct->master ? nf_ct_labels_find(ct->master) : NULL;
 377
 378	if (!master_cl && !have_mask)
 379		return 0;   /* Nothing to do. */
 380
 381	cl = ovs_ct_get_conn_labels(ct);
 382	if (!cl)
 383		return -ENOSPC;
 384
 385	/* Inherit the master's labels, if any. */
 386	if (master_cl)
 387		*cl = *master_cl;
 388
 389	if (have_mask) {
 390		u32 *dst = (u32 *)cl->bits;
 391		int i;
 392
 393		for (i = 0; i < OVS_CT_LABELS_LEN_32; i++)
 394			dst[i] = (dst[i] & ~mask->ct_labels_32[i]) |
 395				(labels->ct_labels_32[i]
 396				 & mask->ct_labels_32[i]);
 397	}
 398
 399	/* Labels are included in the IPCTNL_MSG_CT_NEW event only if the
 400	 * IPCT_LABEL bit is set in the event cache.
 401	 */
 402	nf_conntrack_event_cache(IPCT_LABEL, ct);
 403
 404	memcpy(&key->ct.labels, cl->bits, OVS_CT_LABELS_LEN);
 405
 406	return 0;
 407}
 408
 409static int ovs_ct_set_labels(struct nf_conn *ct, struct sw_flow_key *key,
 410			     const struct ovs_key_ct_labels *labels,
 411			     const struct ovs_key_ct_labels *mask)
 412{
 413	struct nf_conn_labels *cl;
 414	int err;
 415
 416	cl = ovs_ct_get_conn_labels(ct);
 417	if (!cl)
 418		return -ENOSPC;
 419
 420	err = nf_connlabels_replace(ct, labels->ct_labels_32,
 421				    mask->ct_labels_32,
 422				    OVS_CT_LABELS_LEN_32);
 423	if (err)
 424		return err;
 425
 426	memcpy(&key->ct.labels, cl->bits, OVS_CT_LABELS_LEN);
 427
 428	return 0;
 429}
 430
 431/* 'skb' should already be pulled to nh_ofs. */
 432static int ovs_ct_helper(struct sk_buff *skb, u16 proto)
 433{
 434	const struct nf_conntrack_helper *helper;
 435	const struct nf_conn_help *help;
 436	enum ip_conntrack_info ctinfo;
 437	unsigned int protoff;
 438	struct nf_conn *ct;
 439	int err;
 440
 441	ct = nf_ct_get(skb, &ctinfo);
 442	if (!ct || ctinfo == IP_CT_RELATED_REPLY)
 443		return NF_ACCEPT;
 444
 445	help = nfct_help(ct);
 446	if (!help)
 447		return NF_ACCEPT;
 448
 449	helper = rcu_dereference(help->helper);
 450	if (!helper)
 451		return NF_ACCEPT;
 452
 453	switch (proto) {
 454	case NFPROTO_IPV4:
 455		protoff = ip_hdrlen(skb);
 456		break;
 457	case NFPROTO_IPV6: {
 458		u8 nexthdr = ipv6_hdr(skb)->nexthdr;
 459		__be16 frag_off;
 460		int ofs;
 461
 462		ofs = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr,
 463				       &frag_off);
 464		if (ofs < 0 || (frag_off & htons(~0x7)) != 0) {
 465			pr_debug("proto header not found\n");
 466			return NF_ACCEPT;
 467		}
 468		protoff = ofs;
 469		break;
 470	}
 471	default:
 472		WARN_ONCE(1, "helper invoked on non-IP family!");
 473		return NF_DROP;
 474	}
 475
 476	err = helper->help(skb, protoff, ct, ctinfo);
 477	if (err != NF_ACCEPT)
 478		return err;
 479
 480	/* Adjust seqs after helper.  This is needed due to some helpers (e.g.,
 481	 * FTP with NAT) adusting the TCP payload size when mangling IP
 482	 * addresses and/or port numbers in the text-based control connection.
 483	 */
 484	if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
 485	    !nf_ct_seq_adjust(skb, ct, ctinfo, protoff))
 486		return NF_DROP;
 487	return NF_ACCEPT;
 488}
 489
 490/* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero
 491 * value if 'skb' is freed.
 492 */
 493static int handle_fragments(struct net *net, struct sw_flow_key *key,
 494			    u16 zone, struct sk_buff *skb)
 495{
 496	struct ovs_skb_cb ovs_cb = *OVS_CB(skb);
 497	int err;
 498
 499	if (key->eth.type == htons(ETH_P_IP)) {
 500		enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone;
 501
 502		memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
 503		err = ip_defrag(net, skb, user);
 504		if (err)
 505			return err;
 506
 507		ovs_cb.mru = IPCB(skb)->frag_max_size;
 508#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
 509	} else if (key->eth.type == htons(ETH_P_IPV6)) {
 510		enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone;
 511
 512		memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
 513		err = nf_ct_frag6_gather(net, skb, user);
 514		if (err) {
 515			if (err != -EINPROGRESS)
 516				kfree_skb(skb);
 517			return err;
 518		}
 519
 520		key->ip.proto = ipv6_hdr(skb)->nexthdr;
 521		ovs_cb.mru = IP6CB(skb)->frag_max_size;
 522#endif
 523	} else {
 524		kfree_skb(skb);
 525		return -EPFNOSUPPORT;
 526	}
 527
 528	/* The key extracted from the fragment that completed this datagram
 529	 * likely didn't have an L4 header, so regenerate it.
 530	 */
 531	ovs_flow_key_update_l3l4(skb, key);
 532
 533	key->ip.frag = OVS_FRAG_TYPE_NONE;
 534	skb_clear_hash(skb);
 535	skb->ignore_df = 1;
 536	*OVS_CB(skb) = ovs_cb;
 537
 538	return 0;
 539}
 540
 541static struct nf_conntrack_expect *
 542ovs_ct_expect_find(struct net *net, const struct nf_conntrack_zone *zone,
 543		   u16 proto, const struct sk_buff *skb)
 544{
 545	struct nf_conntrack_tuple tuple;
 546	struct nf_conntrack_expect *exp;
 547
 548	if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb), proto, net, &tuple))
 549		return NULL;
 550
 551	exp = __nf_ct_expect_find(net, zone, &tuple);
 552	if (exp) {
 553		struct nf_conntrack_tuple_hash *h;
 554
 555		/* Delete existing conntrack entry, if it clashes with the
 556		 * expectation.  This can happen since conntrack ALGs do not
 557		 * check for clashes between (new) expectations and existing
 558		 * conntrack entries.  nf_conntrack_in() will check the
 559		 * expectations only if a conntrack entry can not be found,
 560		 * which can lead to OVS finding the expectation (here) in the
 561		 * init direction, but which will not be removed by the
 562		 * nf_conntrack_in() call, if a matching conntrack entry is
 563		 * found instead.  In this case all init direction packets
 564		 * would be reported as new related packets, while reply
 565		 * direction packets would be reported as un-related
 566		 * established packets.
 567		 */
 568		h = nf_conntrack_find_get(net, zone, &tuple);
 569		if (h) {
 570			struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h);
 571
 572			nf_ct_delete(ct, 0, 0);
 573			nf_conntrack_put(&ct->ct_general);
 574		}
 575	}
 576
 577	return exp;
 578}
 579
 580/* This replicates logic from nf_conntrack_core.c that is not exported. */
 581static enum ip_conntrack_info
 582ovs_ct_get_info(const struct nf_conntrack_tuple_hash *h)
 583{
 584	const struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h);
 585
 586	if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY)
 587		return IP_CT_ESTABLISHED_REPLY;
 588	/* Once we've had two way comms, always ESTABLISHED. */
 589	if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status))
 590		return IP_CT_ESTABLISHED;
 591	if (test_bit(IPS_EXPECTED_BIT, &ct->status))
 592		return IP_CT_RELATED;
 593	return IP_CT_NEW;
 594}
 595
 596/* Find an existing connection which this packet belongs to without
 597 * re-attributing statistics or modifying the connection state.  This allows an
 598 * skb->_nfct lost due to an upcall to be recovered during actions execution.
 599 *
 600 * Must be called with rcu_read_lock.
 601 *
 602 * On success, populates skb->_nfct and returns the connection.  Returns NULL
 603 * if there is no existing entry.
 604 */
 605static struct nf_conn *
 606ovs_ct_find_existing(struct net *net, const struct nf_conntrack_zone *zone,
 607		     u8 l3num, struct sk_buff *skb, bool natted)
 608{
 609	struct nf_conntrack_tuple tuple;
 610	struct nf_conntrack_tuple_hash *h;
 611	struct nf_conn *ct;
 612
 613	if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb), l3num,
 614			       net, &tuple)) {
 615		pr_debug("ovs_ct_find_existing: Can't get tuple\n");
 616		return NULL;
 617	}
 618
 619	/* Must invert the tuple if skb has been transformed by NAT. */
 620	if (natted) {
 621		struct nf_conntrack_tuple inverse;
 622
 623		if (!nf_ct_invert_tuple(&inverse, &tuple)) {
 624			pr_debug("ovs_ct_find_existing: Inversion failed!\n");
 625			return NULL;
 626		}
 627		tuple = inverse;
 628	}
 629
 630	/* look for tuple match */
 631	h = nf_conntrack_find_get(net, zone, &tuple);
 632	if (!h)
 633		return NULL;   /* Not found. */
 634
 635	ct = nf_ct_tuplehash_to_ctrack(h);
 636
 637	/* Inverted packet tuple matches the reverse direction conntrack tuple,
 638	 * select the other tuplehash to get the right 'ctinfo' bits for this
 639	 * packet.
 640	 */
 641	if (natted)
 642		h = &ct->tuplehash[!h->tuple.dst.dir];
 643
 644	nf_ct_set(skb, ct, ovs_ct_get_info(h));
 645	return ct;
 646}
 647
 648static
 649struct nf_conn *ovs_ct_executed(struct net *net,
 650				const struct sw_flow_key *key,
 651				const struct ovs_conntrack_info *info,
 652				struct sk_buff *skb,
 653				bool *ct_executed)
 654{
 655	struct nf_conn *ct = NULL;
 656
 657	/* If no ct, check if we have evidence that an existing conntrack entry
 658	 * might be found for this skb.  This happens when we lose a skb->_nfct
 659	 * due to an upcall, or if the direction is being forced.  If the
 660	 * connection was not confirmed, it is not cached and needs to be run
 661	 * through conntrack again.
 662	 */
 663	*ct_executed = (key->ct_state & OVS_CS_F_TRACKED) &&
 664		       !(key->ct_state & OVS_CS_F_INVALID) &&
 665		       (key->ct_zone == info->zone.id);
 666
 667	if (*ct_executed || (!key->ct_state && info->force)) {
 668		ct = ovs_ct_find_existing(net, &info->zone, info->family, skb,
 669					  !!(key->ct_state &
 670					  OVS_CS_F_NAT_MASK));
 671	}
 672
 673	return ct;
 674}
 675
 676/* Determine whether skb->_nfct is equal to the result of conntrack lookup. */
 677static bool skb_nfct_cached(struct net *net,
 678			    const struct sw_flow_key *key,
 679			    const struct ovs_conntrack_info *info,
 680			    struct sk_buff *skb)
 681{
 682	enum ip_conntrack_info ctinfo;
 683	struct nf_conn *ct;
 684	bool ct_executed = true;
 685
 686	ct = nf_ct_get(skb, &ctinfo);
 687	if (!ct)
 688		ct = ovs_ct_executed(net, key, info, skb, &ct_executed);
 689
 690	if (ct)
 691		nf_ct_get(skb, &ctinfo);
 692	else
 693		return false;
 694
 695	if (!net_eq(net, read_pnet(&ct->ct_net)))
 696		return false;
 697	if (!nf_ct_zone_equal_any(info->ct, nf_ct_zone(ct)))
 698		return false;
 699	if (info->helper) {
 700		struct nf_conn_help *help;
 701
 702		help = nf_ct_ext_find(ct, NF_CT_EXT_HELPER);
 703		if (help && rcu_access_pointer(help->helper) != info->helper)
 704			return false;
 705	}
 706	if (info->nf_ct_timeout) {
 707		struct nf_conn_timeout *timeout_ext;
 708
 709		timeout_ext = nf_ct_timeout_find(ct);
 710		if (!timeout_ext || info->nf_ct_timeout !=
 711		    rcu_dereference(timeout_ext->timeout))
 712			return false;
 713	}
 714	/* Force conntrack entry direction to the current packet? */
 715	if (info->force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) {
 716		/* Delete the conntrack entry if confirmed, else just release
 717		 * the reference.
 718		 */
 719		if (nf_ct_is_confirmed(ct))
 720			nf_ct_delete(ct, 0, 0);
 721
 722		nf_conntrack_put(&ct->ct_general);
 723		nf_ct_set(skb, NULL, 0);
 724		return false;
 725	}
 726
 727	return ct_executed;
 728}
 729
 730#if IS_ENABLED(CONFIG_NF_NAT)
 731/* Modelled after nf_nat_ipv[46]_fn().
 732 * range is only used for new, uninitialized NAT state.
 733 * Returns either NF_ACCEPT or NF_DROP.
 734 */
 735static int ovs_ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct,
 736			      enum ip_conntrack_info ctinfo,
 737			      const struct nf_nat_range2 *range,
 738			      enum nf_nat_manip_type maniptype)
 739{
 740	int hooknum, nh_off, err = NF_ACCEPT;
 741
 742	nh_off = skb_network_offset(skb);
 743	skb_pull_rcsum(skb, nh_off);
 744
 745	/* See HOOK2MANIP(). */
 746	if (maniptype == NF_NAT_MANIP_SRC)
 747		hooknum = NF_INET_LOCAL_IN; /* Source NAT */
 748	else
 749		hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */
 750
 751	switch (ctinfo) {
 752	case IP_CT_RELATED:
 753	case IP_CT_RELATED_REPLY:
 754		if (IS_ENABLED(CONFIG_NF_NAT) &&
 755		    skb->protocol == htons(ETH_P_IP) &&
 756		    ip_hdr(skb)->protocol == IPPROTO_ICMP) {
 757			if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo,
 758							   hooknum))
 759				err = NF_DROP;
 760			goto push;
 761		} else if (IS_ENABLED(CONFIG_IPV6) &&
 762			   skb->protocol == htons(ETH_P_IPV6)) {
 763			__be16 frag_off;
 764			u8 nexthdr = ipv6_hdr(skb)->nexthdr;
 765			int hdrlen = ipv6_skip_exthdr(skb,
 766						      sizeof(struct ipv6hdr),
 767						      &nexthdr, &frag_off);
 768
 769			if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) {
 770				if (!nf_nat_icmpv6_reply_translation(skb, ct,
 771								     ctinfo,
 772								     hooknum,
 773								     hdrlen))
 774					err = NF_DROP;
 775				goto push;
 776			}
 777		}
 778		/* Non-ICMP, fall thru to initialize if needed. */
 779		/* fall through */
 780	case IP_CT_NEW:
 781		/* Seen it before?  This can happen for loopback, retrans,
 782		 * or local packets.
 783		 */
 784		if (!nf_nat_initialized(ct, maniptype)) {
 785			/* Initialize according to the NAT action. */
 786			err = (range && range->flags & NF_NAT_RANGE_MAP_IPS)
 787				/* Action is set up to establish a new
 788				 * mapping.
 789				 */
 790				? nf_nat_setup_info(ct, range, maniptype)
 791				: nf_nat_alloc_null_binding(ct, hooknum);
 792			if (err != NF_ACCEPT)
 793				goto push;
 794		}
 795		break;
 796
 797	case IP_CT_ESTABLISHED:
 798	case IP_CT_ESTABLISHED_REPLY:
 799		break;
 800
 801	default:
 802		err = NF_DROP;
 803		goto push;
 804	}
 805
 806	err = nf_nat_packet(ct, ctinfo, hooknum, skb);
 807push:
 808	skb_push(skb, nh_off);
 809	skb_postpush_rcsum(skb, skb->data, nh_off);
 810
 811	return err;
 812}
 813
 814static void ovs_nat_update_key(struct sw_flow_key *key,
 815			       const struct sk_buff *skb,
 816			       enum nf_nat_manip_type maniptype)
 817{
 818	if (maniptype == NF_NAT_MANIP_SRC) {
 819		__be16 src;
 820
 821		key->ct_state |= OVS_CS_F_SRC_NAT;
 822		if (key->eth.type == htons(ETH_P_IP))
 823			key->ipv4.addr.src = ip_hdr(skb)->saddr;
 824		else if (key->eth.type == htons(ETH_P_IPV6))
 825			memcpy(&key->ipv6.addr.src, &ipv6_hdr(skb)->saddr,
 826			       sizeof(key->ipv6.addr.src));
 827		else
 828			return;
 829
 830		if (key->ip.proto == IPPROTO_UDP)
 831			src = udp_hdr(skb)->source;
 832		else if (key->ip.proto == IPPROTO_TCP)
 833			src = tcp_hdr(skb)->source;
 834		else if (key->ip.proto == IPPROTO_SCTP)
 835			src = sctp_hdr(skb)->source;
 836		else
 837			return;
 838
 839		key->tp.src = src;
 840	} else {
 841		__be16 dst;
 842
 843		key->ct_state |= OVS_CS_F_DST_NAT;
 844		if (key->eth.type == htons(ETH_P_IP))
 845			key->ipv4.addr.dst = ip_hdr(skb)->daddr;
 846		else if (key->eth.type == htons(ETH_P_IPV6))
 847			memcpy(&key->ipv6.addr.dst, &ipv6_hdr(skb)->daddr,
 848			       sizeof(key->ipv6.addr.dst));
 849		else
 850			return;
 851
 852		if (key->ip.proto == IPPROTO_UDP)
 853			dst = udp_hdr(skb)->dest;
 854		else if (key->ip.proto == IPPROTO_TCP)
 855			dst = tcp_hdr(skb)->dest;
 856		else if (key->ip.proto == IPPROTO_SCTP)
 857			dst = sctp_hdr(skb)->dest;
 858		else
 859			return;
 860
 861		key->tp.dst = dst;
 862	}
 863}
 864
 865/* Returns NF_DROP if the packet should be dropped, NF_ACCEPT otherwise. */
 866static int ovs_ct_nat(struct net *net, struct sw_flow_key *key,
 867		      const struct ovs_conntrack_info *info,
 868		      struct sk_buff *skb, struct nf_conn *ct,
 869		      enum ip_conntrack_info ctinfo)
 870{
 871	enum nf_nat_manip_type maniptype;
 872	int err;
 873
 874	/* Add NAT extension if not confirmed yet. */
 875	if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct))
 876		return NF_ACCEPT;   /* Can't NAT. */
 877
 878	/* Determine NAT type.
 879	 * Check if the NAT type can be deduced from the tracked connection.
 880	 * Make sure new expected connections (IP_CT_RELATED) are NATted only
 881	 * when committing.
 882	 */
 883	if (info->nat & OVS_CT_NAT && ctinfo != IP_CT_NEW &&
 884	    ct->status & IPS_NAT_MASK &&
 885	    (ctinfo != IP_CT_RELATED || info->commit)) {
 886		/* NAT an established or related connection like before. */
 887		if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY)
 888			/* This is the REPLY direction for a connection
 889			 * for which NAT was applied in the forward
 890			 * direction.  Do the reverse NAT.
 891			 */
 892			maniptype = ct->status & IPS_SRC_NAT
 893				? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC;
 894		else
 895			maniptype = ct->status & IPS_SRC_NAT
 896				? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST;
 897	} else if (info->nat & OVS_CT_SRC_NAT) {
 898		maniptype = NF_NAT_MANIP_SRC;
 899	} else if (info->nat & OVS_CT_DST_NAT) {
 900		maniptype = NF_NAT_MANIP_DST;
 901	} else {
 902		return NF_ACCEPT; /* Connection is not NATed. */
 903	}
 904	err = ovs_ct_nat_execute(skb, ct, ctinfo, &info->range, maniptype);
 905
 906	/* Mark NAT done if successful and update the flow key. */
 907	if (err == NF_ACCEPT)
 908		ovs_nat_update_key(key, skb, maniptype);
 
 909
 910	return err;
 911}
 912#else /* !CONFIG_NF_NAT */
 913static int ovs_ct_nat(struct net *net, struct sw_flow_key *key,
 914		      const struct ovs_conntrack_info *info,
 915		      struct sk_buff *skb, struct nf_conn *ct,
 916		      enum ip_conntrack_info ctinfo)
 917{
 918	return NF_ACCEPT;
 919}
 920#endif
 921
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 922/* Pass 'skb' through conntrack in 'net', using zone configured in 'info', if
 923 * not done already.  Update key with new CT state after passing the packet
 924 * through conntrack.
 925 * Note that if the packet is deemed invalid by conntrack, skb->_nfct will be
 926 * set to NULL and 0 will be returned.
 927 */
 928static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
 929			   const struct ovs_conntrack_info *info,
 930			   struct sk_buff *skb)
 931{
 932	/* If we are recirculating packets to match on conntrack fields and
 933	 * committing with a separate conntrack action,  then we don't need to
 934	 * actually run the packet through conntrack twice unless it's for a
 935	 * different zone.
 936	 */
 937	bool cached = skb_nfct_cached(net, key, info, skb);
 938	enum ip_conntrack_info ctinfo;
 939	struct nf_conn *ct;
 940
 941	if (!cached) {
 942		struct nf_hook_state state = {
 943			.hook = NF_INET_PRE_ROUTING,
 944			.pf = info->family,
 945			.net = net,
 946		};
 947		struct nf_conn *tmpl = info->ct;
 948		int err;
 949
 950		/* Associate skb with specified zone. */
 951		if (tmpl) {
 952			if (skb_nfct(skb))
 953				nf_conntrack_put(skb_nfct(skb));
 954			nf_conntrack_get(&tmpl->ct_general);
 955			nf_ct_set(skb, tmpl, IP_CT_NEW);
 956		}
 957
 958		err = nf_conntrack_in(skb, &state);
 959		if (err != NF_ACCEPT)
 960			return -ENOENT;
 961
 962		/* Clear CT state NAT flags to mark that we have not yet done
 963		 * NAT after the nf_conntrack_in() call.  We can actually clear
 964		 * the whole state, as it will be re-initialized below.
 965		 */
 966		key->ct_state = 0;
 967
 968		/* Update the key, but keep the NAT flags. */
 969		ovs_ct_update_key(skb, info, key, true, true);
 970	}
 971
 972	ct = nf_ct_get(skb, &ctinfo);
 973	if (ct) {
 
 
 974		/* Packets starting a new connection must be NATted before the
 975		 * helper, so that the helper knows about the NAT.  We enforce
 976		 * this by delaying both NAT and helper calls for unconfirmed
 977		 * connections until the committing CT action.  For later
 978		 * packets NAT and Helper may be called in either order.
 979		 *
 980		 * NAT will be done only if the CT action has NAT, and only
 981		 * once per packet (per zone), as guarded by the NAT bits in
 982		 * the key->ct_state.
 983		 */
 984		if (info->nat && !(key->ct_state & OVS_CS_F_NAT_MASK) &&
 985		    (nf_ct_is_confirmed(ct) || info->commit) &&
 986		    ovs_ct_nat(net, key, info, skb, ct, ctinfo) != NF_ACCEPT) {
 987			return -EINVAL;
 
 
 
 988		}
 989
 990		/* Userspace may decide to perform a ct lookup without a helper
 991		 * specified followed by a (recirculate and) commit with one.
 992		 * Therefore, for unconfirmed connections which we will commit,
 993		 * we need to attach the helper here.
 
 994		 */
 995		if (!nf_ct_is_confirmed(ct) && info->commit &&
 996		    info->helper && !nfct_help(ct)) {
 997			int err = __nf_ct_try_assign_helper(ct, info->ct,
 998							    GFP_ATOMIC);
 999			if (err)
1000				return err;
 
1001
1002			/* helper installed, add seqadj if NAT is required */
1003			if (info->nat && !nfct_seqadj(ct)) {
1004				if (!nfct_seqadj_ext_add(ct))
1005					return -EINVAL;
1006			}
1007		}
1008
1009		/* Call the helper only if:
1010		 * - nf_conntrack_in() was executed above ("!cached") for a
1011		 *   confirmed connection, or
 
1012		 * - When committing an unconfirmed connection.
1013		 */
1014		if ((nf_ct_is_confirmed(ct) ? !cached : info->commit) &&
1015		    ovs_ct_helper(skb, info->family) != NF_ACCEPT) {
1016			return -EINVAL;
 
 
 
 
1017		}
 
 
 
 
 
 
 
 
 
 
1018	}
1019
1020	return 0;
1021}
1022
1023/* Lookup connection and read fields into key. */
1024static int ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
1025			 const struct ovs_conntrack_info *info,
1026			 struct sk_buff *skb)
1027{
1028	struct nf_conntrack_expect *exp;
1029
1030	/* If we pass an expected packet through nf_conntrack_in() the
1031	 * expectation is typically removed, but the packet could still be
1032	 * lost in upcall processing.  To prevent this from happening we
1033	 * perform an explicit expectation lookup.  Expected connections are
1034	 * always new, and will be passed through conntrack only when they are
1035	 * committed, as it is OK to remove the expectation at that time.
1036	 */
1037	exp = ovs_ct_expect_find(net, &info->zone, info->family, skb);
1038	if (exp) {
1039		u8 state;
1040
1041		/* NOTE: New connections are NATted and Helped only when
1042		 * committed, so we are not calling into NAT here.
1043		 */
1044		state = OVS_CS_F_TRACKED | OVS_CS_F_NEW | OVS_CS_F_RELATED;
1045		__ovs_ct_update_key(key, state, &info->zone, exp->master);
1046	} else {
1047		struct nf_conn *ct;
1048		int err;
1049
1050		err = __ovs_ct_lookup(net, key, info, skb);
1051		if (err)
1052			return err;
1053
1054		ct = (struct nf_conn *)skb_nfct(skb);
1055		if (ct)
1056			nf_ct_deliver_cached_events(ct);
1057	}
1058
1059	return 0;
1060}
1061
1062static bool labels_nonzero(const struct ovs_key_ct_labels *labels)
1063{
1064	size_t i;
1065
1066	for (i = 0; i < OVS_CT_LABELS_LEN_32; i++)
1067		if (labels->ct_labels_32[i])
1068			return true;
1069
1070	return false;
1071}
1072
1073#if	IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
1074static struct hlist_head *ct_limit_hash_bucket(
1075	const struct ovs_ct_limit_info *info, u16 zone)
1076{
1077	return &info->limits[zone & (CT_LIMIT_HASH_BUCKETS - 1)];
1078}
1079
1080/* Call with ovs_mutex */
1081static void ct_limit_set(const struct ovs_ct_limit_info *info,
1082			 struct ovs_ct_limit *new_ct_limit)
1083{
1084	struct ovs_ct_limit *ct_limit;
1085	struct hlist_head *head;
1086
1087	head = ct_limit_hash_bucket(info, new_ct_limit->zone);
1088	hlist_for_each_entry_rcu(ct_limit, head, hlist_node) {
1089		if (ct_limit->zone == new_ct_limit->zone) {
1090			hlist_replace_rcu(&ct_limit->hlist_node,
1091					  &new_ct_limit->hlist_node);
1092			kfree_rcu(ct_limit, rcu);
1093			return;
1094		}
1095	}
1096
1097	hlist_add_head_rcu(&new_ct_limit->hlist_node, head);
1098}
1099
1100/* Call with ovs_mutex */
1101static void ct_limit_del(const struct ovs_ct_limit_info *info, u16 zone)
1102{
1103	struct ovs_ct_limit *ct_limit;
1104	struct hlist_head *head;
1105	struct hlist_node *n;
1106
1107	head = ct_limit_hash_bucket(info, zone);
1108	hlist_for_each_entry_safe(ct_limit, n, head, hlist_node) {
1109		if (ct_limit->zone == zone) {
1110			hlist_del_rcu(&ct_limit->hlist_node);
1111			kfree_rcu(ct_limit, rcu);
1112			return;
1113		}
1114	}
1115}
1116
1117/* Call with RCU read lock */
1118static u32 ct_limit_get(const struct ovs_ct_limit_info *info, u16 zone)
1119{
1120	struct ovs_ct_limit *ct_limit;
1121	struct hlist_head *head;
1122
1123	head = ct_limit_hash_bucket(info, zone);
1124	hlist_for_each_entry_rcu(ct_limit, head, hlist_node) {
1125		if (ct_limit->zone == zone)
1126			return ct_limit->limit;
1127	}
1128
1129	return info->default_limit;
1130}
1131
1132static int ovs_ct_check_limit(struct net *net,
1133			      const struct ovs_conntrack_info *info,
1134			      const struct nf_conntrack_tuple *tuple)
1135{
1136	struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
1137	const struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
1138	u32 per_zone_limit, connections;
1139	u32 conncount_key;
1140
1141	conncount_key = info->zone.id;
1142
1143	per_zone_limit = ct_limit_get(ct_limit_info, info->zone.id);
1144	if (per_zone_limit == OVS_CT_LIMIT_UNLIMITED)
1145		return 0;
1146
1147	connections = nf_conncount_count(net, ct_limit_info->data,
1148					 &conncount_key, tuple, &info->zone);
1149	if (connections > per_zone_limit)
1150		return -ENOMEM;
1151
1152	return 0;
1153}
1154#endif
1155
1156/* Lookup connection and confirm if unconfirmed. */
1157static int ovs_ct_commit(struct net *net, struct sw_flow_key *key,
1158			 const struct ovs_conntrack_info *info,
1159			 struct sk_buff *skb)
1160{
1161	enum ip_conntrack_info ctinfo;
1162	struct nf_conn *ct;
1163	int err;
1164
1165	err = __ovs_ct_lookup(net, key, info, skb);
1166	if (err)
1167		return err;
1168
1169	/* The connection could be invalid, in which case this is a no-op.*/
1170	ct = nf_ct_get(skb, &ctinfo);
1171	if (!ct)
1172		return 0;
1173
1174#if	IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
1175	if (static_branch_unlikely(&ovs_ct_limit_enabled)) {
1176		if (!nf_ct_is_confirmed(ct)) {
1177			err = ovs_ct_check_limit(net, info,
1178				&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
1179			if (err) {
1180				net_warn_ratelimited("openvswitch: zone: %u "
1181					"exceeds conntrack limit\n",
1182					info->zone.id);
1183				return err;
1184			}
1185		}
1186	}
1187#endif
1188
1189	/* Set the conntrack event mask if given.  NEW and DELETE events have
1190	 * their own groups, but the NFNLGRP_CONNTRACK_UPDATE group listener
1191	 * typically would receive many kinds of updates.  Setting the event
1192	 * mask allows those events to be filtered.  The set event mask will
1193	 * remain in effect for the lifetime of the connection unless changed
1194	 * by a further CT action with both the commit flag and the eventmask
1195	 * option. */
1196	if (info->have_eventmask) {
1197		struct nf_conntrack_ecache *cache = nf_ct_ecache_find(ct);
1198
1199		if (cache)
1200			cache->ctmask = info->eventmask;
1201	}
1202
1203	/* Apply changes before confirming the connection so that the initial
1204	 * conntrack NEW netlink event carries the values given in the CT
1205	 * action.
1206	 */
1207	if (info->mark.mask) {
1208		err = ovs_ct_set_mark(ct, key, info->mark.value,
1209				      info->mark.mask);
1210		if (err)
1211			return err;
1212	}
1213	if (!nf_ct_is_confirmed(ct)) {
1214		err = ovs_ct_init_labels(ct, key, &info->labels.value,
1215					 &info->labels.mask);
1216		if (err)
1217			return err;
 
 
1218	} else if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1219		   labels_nonzero(&info->labels.mask)) {
1220		err = ovs_ct_set_labels(ct, key, &info->labels.value,
1221					&info->labels.mask);
1222		if (err)
1223			return err;
1224	}
1225	/* This will take care of sending queued events even if the connection
1226	 * is already confirmed.
1227	 */
1228	if (nf_conntrack_confirm(skb) != NF_ACCEPT)
1229		return -EINVAL;
1230
1231	return 0;
1232}
1233
1234/* Trim the skb to the length specified by the IP/IPv6 header,
1235 * removing any trailing lower-layer padding. This prepares the skb
1236 * for higher-layer processing that assumes skb->len excludes padding
1237 * (such as nf_ip_checksum). The caller needs to pull the skb to the
1238 * network header, and ensure ip_hdr/ipv6_hdr points to valid data.
1239 */
1240static int ovs_skb_network_trim(struct sk_buff *skb)
1241{
1242	unsigned int len;
1243	int err;
1244
1245	switch (skb->protocol) {
1246	case htons(ETH_P_IP):
1247		len = ntohs(ip_hdr(skb)->tot_len);
1248		break;
1249	case htons(ETH_P_IPV6):
1250		len = sizeof(struct ipv6hdr)
1251			+ ntohs(ipv6_hdr(skb)->payload_len);
1252		break;
1253	default:
1254		len = skb->len;
1255	}
1256
1257	err = pskb_trim_rcsum(skb, len);
1258	if (err)
1259		kfree_skb(skb);
1260
1261	return err;
1262}
1263
1264/* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero
1265 * value if 'skb' is freed.
1266 */
1267int ovs_ct_execute(struct net *net, struct sk_buff *skb,
1268		   struct sw_flow_key *key,
1269		   const struct ovs_conntrack_info *info)
1270{
1271	int nh_ofs;
1272	int err;
1273
1274	/* The conntrack module expects to be working at L3. */
1275	nh_ofs = skb_network_offset(skb);
1276	skb_pull_rcsum(skb, nh_ofs);
1277
1278	err = ovs_skb_network_trim(skb);
1279	if (err)
 
1280		return err;
 
1281
1282	if (key->ip.frag != OVS_FRAG_TYPE_NONE) {
1283		err = handle_fragments(net, key, info->zone.id, skb);
 
1284		if (err)
1285			return err;
1286	}
1287
1288	if (info->commit)
1289		err = ovs_ct_commit(net, key, info, skb);
1290	else
1291		err = ovs_ct_lookup(net, key, info, skb);
1292
1293	skb_push(skb, nh_ofs);
1294	skb_postpush_rcsum(skb, skb->data, nh_ofs);
 
 
 
1295	if (err)
1296		kfree_skb(skb);
1297	return err;
1298}
1299
1300int ovs_ct_clear(struct sk_buff *skb, struct sw_flow_key *key)
1301{
1302	if (skb_nfct(skb)) {
1303		nf_conntrack_put(skb_nfct(skb));
1304		nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
1305		ovs_ct_fill_key(skb, key);
1306	}
1307
1308	return 0;
1309}
1310
1311static int ovs_ct_add_helper(struct ovs_conntrack_info *info, const char *name,
1312			     const struct sw_flow_key *key, bool log)
1313{
1314	struct nf_conntrack_helper *helper;
1315	struct nf_conn_help *help;
1316	int ret = 0;
1317
1318	helper = nf_conntrack_helper_try_module_get(name, info->family,
1319						    key->ip.proto);
1320	if (!helper) {
1321		OVS_NLERR(log, "Unknown helper \"%s\"", name);
1322		return -EINVAL;
1323	}
1324
1325	help = nf_ct_helper_ext_add(info->ct, GFP_KERNEL);
1326	if (!help) {
1327		nf_conntrack_helper_put(helper);
1328		return -ENOMEM;
1329	}
1330
1331#if IS_ENABLED(CONFIG_NF_NAT)
1332	if (info->nat) {
1333		ret = nf_nat_helper_try_module_get(name, info->family,
1334						   key->ip.proto);
1335		if (ret) {
1336			nf_conntrack_helper_put(helper);
1337			OVS_NLERR(log, "Failed to load \"%s\" NAT helper, error: %d",
1338				  name, ret);
1339			return ret;
1340		}
1341	}
1342#endif
1343	rcu_assign_pointer(help->helper, helper);
1344	info->helper = helper;
1345	return ret;
1346}
1347
1348#if IS_ENABLED(CONFIG_NF_NAT)
1349static int parse_nat(const struct nlattr *attr,
1350		     struct ovs_conntrack_info *info, bool log)
1351{
1352	struct nlattr *a;
1353	int rem;
1354	bool have_ip_max = false;
1355	bool have_proto_max = false;
1356	bool ip_vers = (info->family == NFPROTO_IPV6);
1357
1358	nla_for_each_nested(a, attr, rem) {
1359		static const int ovs_nat_attr_lens[OVS_NAT_ATTR_MAX + 1][2] = {
1360			[OVS_NAT_ATTR_SRC] = {0, 0},
1361			[OVS_NAT_ATTR_DST] = {0, 0},
1362			[OVS_NAT_ATTR_IP_MIN] = {sizeof(struct in_addr),
1363						 sizeof(struct in6_addr)},
1364			[OVS_NAT_ATTR_IP_MAX] = {sizeof(struct in_addr),
1365						 sizeof(struct in6_addr)},
1366			[OVS_NAT_ATTR_PROTO_MIN] = {sizeof(u16), sizeof(u16)},
1367			[OVS_NAT_ATTR_PROTO_MAX] = {sizeof(u16), sizeof(u16)},
1368			[OVS_NAT_ATTR_PERSISTENT] = {0, 0},
1369			[OVS_NAT_ATTR_PROTO_HASH] = {0, 0},
1370			[OVS_NAT_ATTR_PROTO_RANDOM] = {0, 0},
1371		};
1372		int type = nla_type(a);
1373
1374		if (type > OVS_NAT_ATTR_MAX) {
1375			OVS_NLERR(log, "Unknown NAT attribute (type=%d, max=%d)",
1376				  type, OVS_NAT_ATTR_MAX);
1377			return -EINVAL;
1378		}
1379
1380		if (nla_len(a) != ovs_nat_attr_lens[type][ip_vers]) {
1381			OVS_NLERR(log, "NAT attribute type %d has unexpected length (%d != %d)",
1382				  type, nla_len(a),
1383				  ovs_nat_attr_lens[type][ip_vers]);
1384			return -EINVAL;
1385		}
1386
1387		switch (type) {
1388		case OVS_NAT_ATTR_SRC:
1389		case OVS_NAT_ATTR_DST:
1390			if (info->nat) {
1391				OVS_NLERR(log, "Only one type of NAT may be specified");
1392				return -ERANGE;
1393			}
1394			info->nat |= OVS_CT_NAT;
1395			info->nat |= ((type == OVS_NAT_ATTR_SRC)
1396					? OVS_CT_SRC_NAT : OVS_CT_DST_NAT);
1397			break;
1398
1399		case OVS_NAT_ATTR_IP_MIN:
1400			nla_memcpy(&info->range.min_addr, a,
1401				   sizeof(info->range.min_addr));
1402			info->range.flags |= NF_NAT_RANGE_MAP_IPS;
1403			break;
1404
1405		case OVS_NAT_ATTR_IP_MAX:
1406			have_ip_max = true;
1407			nla_memcpy(&info->range.max_addr, a,
1408				   sizeof(info->range.max_addr));
1409			info->range.flags |= NF_NAT_RANGE_MAP_IPS;
1410			break;
1411
1412		case OVS_NAT_ATTR_PROTO_MIN:
1413			info->range.min_proto.all = htons(nla_get_u16(a));
1414			info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1415			break;
1416
1417		case OVS_NAT_ATTR_PROTO_MAX:
1418			have_proto_max = true;
1419			info->range.max_proto.all = htons(nla_get_u16(a));
1420			info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1421			break;
1422
1423		case OVS_NAT_ATTR_PERSISTENT:
1424			info->range.flags |= NF_NAT_RANGE_PERSISTENT;
1425			break;
1426
1427		case OVS_NAT_ATTR_PROTO_HASH:
1428			info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM;
1429			break;
1430
1431		case OVS_NAT_ATTR_PROTO_RANDOM:
1432			info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM_FULLY;
1433			break;
1434
1435		default:
1436			OVS_NLERR(log, "Unknown nat attribute (%d)", type);
1437			return -EINVAL;
1438		}
1439	}
1440
1441	if (rem > 0) {
1442		OVS_NLERR(log, "NAT attribute has %d unknown bytes", rem);
1443		return -EINVAL;
1444	}
1445	if (!info->nat) {
1446		/* Do not allow flags if no type is given. */
1447		if (info->range.flags) {
1448			OVS_NLERR(log,
1449				  "NAT flags may be given only when NAT range (SRC or DST) is also specified."
1450				  );
1451			return -EINVAL;
1452		}
1453		info->nat = OVS_CT_NAT;   /* NAT existing connections. */
1454	} else if (!info->commit) {
1455		OVS_NLERR(log,
1456			  "NAT attributes may be specified only when CT COMMIT flag is also specified."
1457			  );
1458		return -EINVAL;
1459	}
1460	/* Allow missing IP_MAX. */
1461	if (info->range.flags & NF_NAT_RANGE_MAP_IPS && !have_ip_max) {
1462		memcpy(&info->range.max_addr, &info->range.min_addr,
1463		       sizeof(info->range.max_addr));
1464	}
1465	/* Allow missing PROTO_MAX. */
1466	if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED &&
1467	    !have_proto_max) {
1468		info->range.max_proto.all = info->range.min_proto.all;
1469	}
1470	return 0;
1471}
1472#endif
1473
1474static const struct ovs_ct_len_tbl ovs_ct_attr_lens[OVS_CT_ATTR_MAX + 1] = {
1475	[OVS_CT_ATTR_COMMIT]	= { .minlen = 0, .maxlen = 0 },
1476	[OVS_CT_ATTR_FORCE_COMMIT]	= { .minlen = 0, .maxlen = 0 },
1477	[OVS_CT_ATTR_ZONE]	= { .minlen = sizeof(u16),
1478				    .maxlen = sizeof(u16) },
1479	[OVS_CT_ATTR_MARK]	= { .minlen = sizeof(struct md_mark),
1480				    .maxlen = sizeof(struct md_mark) },
1481	[OVS_CT_ATTR_LABELS]	= { .minlen = sizeof(struct md_labels),
1482				    .maxlen = sizeof(struct md_labels) },
1483	[OVS_CT_ATTR_HELPER]	= { .minlen = 1,
1484				    .maxlen = NF_CT_HELPER_NAME_LEN },
1485#if IS_ENABLED(CONFIG_NF_NAT)
1486	/* NAT length is checked when parsing the nested attributes. */
1487	[OVS_CT_ATTR_NAT]	= { .minlen = 0, .maxlen = INT_MAX },
1488#endif
1489	[OVS_CT_ATTR_EVENTMASK]	= { .minlen = sizeof(u32),
1490				    .maxlen = sizeof(u32) },
1491	[OVS_CT_ATTR_TIMEOUT] = { .minlen = 1,
1492				  .maxlen = CTNL_TIMEOUT_NAME_MAX },
1493};
1494
1495static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info,
1496		    const char **helper, bool log)
1497{
1498	struct nlattr *a;
1499	int rem;
1500
1501	nla_for_each_nested(a, attr, rem) {
1502		int type = nla_type(a);
1503		int maxlen;
1504		int minlen;
1505
1506		if (type > OVS_CT_ATTR_MAX) {
1507			OVS_NLERR(log,
1508				  "Unknown conntrack attr (type=%d, max=%d)",
1509				  type, OVS_CT_ATTR_MAX);
1510			return -EINVAL;
1511		}
1512
1513		maxlen = ovs_ct_attr_lens[type].maxlen;
1514		minlen = ovs_ct_attr_lens[type].minlen;
1515		if (nla_len(a) < minlen || nla_len(a) > maxlen) {
1516			OVS_NLERR(log,
1517				  "Conntrack attr type has unexpected length (type=%d, length=%d, expected=%d)",
1518				  type, nla_len(a), maxlen);
1519			return -EINVAL;
1520		}
1521
1522		switch (type) {
1523		case OVS_CT_ATTR_FORCE_COMMIT:
1524			info->force = true;
1525			/* fall through. */
1526		case OVS_CT_ATTR_COMMIT:
1527			info->commit = true;
1528			break;
1529#ifdef CONFIG_NF_CONNTRACK_ZONES
1530		case OVS_CT_ATTR_ZONE:
1531			info->zone.id = nla_get_u16(a);
1532			break;
1533#endif
1534#ifdef CONFIG_NF_CONNTRACK_MARK
1535		case OVS_CT_ATTR_MARK: {
1536			struct md_mark *mark = nla_data(a);
1537
1538			if (!mark->mask) {
1539				OVS_NLERR(log, "ct_mark mask cannot be 0");
1540				return -EINVAL;
1541			}
1542			info->mark = *mark;
1543			break;
1544		}
1545#endif
1546#ifdef CONFIG_NF_CONNTRACK_LABELS
1547		case OVS_CT_ATTR_LABELS: {
1548			struct md_labels *labels = nla_data(a);
1549
1550			if (!labels_nonzero(&labels->mask)) {
1551				OVS_NLERR(log, "ct_labels mask cannot be 0");
1552				return -EINVAL;
1553			}
1554			info->labels = *labels;
1555			break;
1556		}
1557#endif
1558		case OVS_CT_ATTR_HELPER:
1559			*helper = nla_data(a);
1560			if (!memchr(*helper, '\0', nla_len(a))) {
1561				OVS_NLERR(log, "Invalid conntrack helper");
1562				return -EINVAL;
1563			}
1564			break;
1565#if IS_ENABLED(CONFIG_NF_NAT)
1566		case OVS_CT_ATTR_NAT: {
1567			int err = parse_nat(a, info, log);
1568
1569			if (err)
1570				return err;
1571			break;
1572		}
1573#endif
1574		case OVS_CT_ATTR_EVENTMASK:
1575			info->have_eventmask = true;
1576			info->eventmask = nla_get_u32(a);
1577			break;
1578#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
1579		case OVS_CT_ATTR_TIMEOUT:
1580			memcpy(info->timeout, nla_data(a), nla_len(a));
1581			if (!memchr(info->timeout, '\0', nla_len(a))) {
1582				OVS_NLERR(log, "Invalid conntrack timeout");
1583				return -EINVAL;
1584			}
1585			break;
1586#endif
1587
1588		default:
1589			OVS_NLERR(log, "Unknown conntrack attr (%d)",
1590				  type);
1591			return -EINVAL;
1592		}
1593	}
1594
1595#ifdef CONFIG_NF_CONNTRACK_MARK
1596	if (!info->commit && info->mark.mask) {
1597		OVS_NLERR(log,
1598			  "Setting conntrack mark requires 'commit' flag.");
1599		return -EINVAL;
1600	}
1601#endif
1602#ifdef CONFIG_NF_CONNTRACK_LABELS
1603	if (!info->commit && labels_nonzero(&info->labels.mask)) {
1604		OVS_NLERR(log,
1605			  "Setting conntrack labels requires 'commit' flag.");
1606		return -EINVAL;
1607	}
1608#endif
1609	if (rem > 0) {
1610		OVS_NLERR(log, "Conntrack attr has %d unknown bytes", rem);
1611		return -EINVAL;
1612	}
1613
1614	return 0;
1615}
1616
1617bool ovs_ct_verify(struct net *net, enum ovs_key_attr attr)
1618{
1619	if (attr == OVS_KEY_ATTR_CT_STATE)
1620		return true;
1621	if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1622	    attr == OVS_KEY_ATTR_CT_ZONE)
1623		return true;
1624	if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
1625	    attr == OVS_KEY_ATTR_CT_MARK)
1626		return true;
1627	if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1628	    attr == OVS_KEY_ATTR_CT_LABELS) {
1629		struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
1630
1631		return ovs_net->xt_label;
1632	}
1633
1634	return false;
1635}
1636
1637int ovs_ct_copy_action(struct net *net, const struct nlattr *attr,
1638		       const struct sw_flow_key *key,
1639		       struct sw_flow_actions **sfa,  bool log)
1640{
 
1641	struct ovs_conntrack_info ct_info;
1642	const char *helper = NULL;
1643	u16 family;
1644	int err;
1645
1646	family = key_to_nfproto(key);
1647	if (family == NFPROTO_UNSPEC) {
1648		OVS_NLERR(log, "ct family unspecified");
1649		return -EINVAL;
1650	}
1651
1652	memset(&ct_info, 0, sizeof(ct_info));
1653	ct_info.family = family;
1654
1655	nf_ct_zone_init(&ct_info.zone, NF_CT_DEFAULT_ZONE_ID,
1656			NF_CT_DEFAULT_ZONE_DIR, 0);
1657
1658	err = parse_ct(attr, &ct_info, &helper, log);
1659	if (err)
1660		return err;
1661
1662	/* Set up template for tracking connections in specific zones. */
1663	ct_info.ct = nf_ct_tmpl_alloc(net, &ct_info.zone, GFP_KERNEL);
1664	if (!ct_info.ct) {
1665		OVS_NLERR(log, "Failed to allocate conntrack template");
1666		return -ENOMEM;
1667	}
1668
 
 
 
 
 
 
1669	if (ct_info.timeout[0]) {
1670		if (nf_ct_set_timeout(net, ct_info.ct, family, key->ip.proto,
1671				      ct_info.timeout))
1672			pr_info_ratelimited("Failed to associated timeout "
1673					    "policy `%s'\n", ct_info.timeout);
 
1674		else
1675			ct_info.nf_ct_timeout = rcu_dereference(
1676				nf_ct_timeout_find(ct_info.ct)->timeout);
1677
1678	}
1679
1680	if (helper) {
1681		err = ovs_ct_add_helper(&ct_info, helper, key, log);
1682		if (err)
 
 
1683			goto err_free_ct;
 
1684	}
1685
1686	err = ovs_nla_add_action(sfa, OVS_ACTION_ATTR_CT, &ct_info,
1687				 sizeof(ct_info), log);
1688	if (err)
1689		goto err_free_ct;
1690
1691	__set_bit(IPS_CONFIRMED_BIT, &ct_info.ct->status);
1692	nf_conntrack_get(&ct_info.ct->ct_general);
1693	return 0;
1694err_free_ct:
1695	__ovs_ct_free_action(&ct_info);
1696	return err;
1697}
1698
1699#if IS_ENABLED(CONFIG_NF_NAT)
1700static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info,
1701			       struct sk_buff *skb)
1702{
1703	struct nlattr *start;
1704
1705	start = nla_nest_start_noflag(skb, OVS_CT_ATTR_NAT);
1706	if (!start)
1707		return false;
1708
1709	if (info->nat & OVS_CT_SRC_NAT) {
1710		if (nla_put_flag(skb, OVS_NAT_ATTR_SRC))
1711			return false;
1712	} else if (info->nat & OVS_CT_DST_NAT) {
1713		if (nla_put_flag(skb, OVS_NAT_ATTR_DST))
1714			return false;
1715	} else {
1716		goto out;
1717	}
1718
1719	if (info->range.flags & NF_NAT_RANGE_MAP_IPS) {
1720		if (IS_ENABLED(CONFIG_NF_NAT) &&
1721		    info->family == NFPROTO_IPV4) {
1722			if (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MIN,
1723					    info->range.min_addr.ip) ||
1724			    (info->range.max_addr.ip
1725			     != info->range.min_addr.ip &&
1726			     (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MAX,
1727					      info->range.max_addr.ip))))
1728				return false;
1729		} else if (IS_ENABLED(CONFIG_IPV6) &&
1730			   info->family == NFPROTO_IPV6) {
1731			if (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MIN,
1732					     &info->range.min_addr.in6) ||
1733			    (memcmp(&info->range.max_addr.in6,
1734				    &info->range.min_addr.in6,
1735				    sizeof(info->range.max_addr.in6)) &&
1736			     (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MAX,
1737					       &info->range.max_addr.in6))))
1738				return false;
1739		} else {
1740			return false;
1741		}
1742	}
1743	if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED &&
1744	    (nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MIN,
1745			 ntohs(info->range.min_proto.all)) ||
1746	     (info->range.max_proto.all != info->range.min_proto.all &&
1747	      nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MAX,
1748			  ntohs(info->range.max_proto.all)))))
1749		return false;
1750
1751	if (info->range.flags & NF_NAT_RANGE_PERSISTENT &&
1752	    nla_put_flag(skb, OVS_NAT_ATTR_PERSISTENT))
1753		return false;
1754	if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM &&
1755	    nla_put_flag(skb, OVS_NAT_ATTR_PROTO_HASH))
1756		return false;
1757	if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM_FULLY &&
1758	    nla_put_flag(skb, OVS_NAT_ATTR_PROTO_RANDOM))
1759		return false;
1760out:
1761	nla_nest_end(skb, start);
1762
1763	return true;
1764}
1765#endif
1766
1767int ovs_ct_action_to_attr(const struct ovs_conntrack_info *ct_info,
1768			  struct sk_buff *skb)
1769{
1770	struct nlattr *start;
1771
1772	start = nla_nest_start_noflag(skb, OVS_ACTION_ATTR_CT);
1773	if (!start)
1774		return -EMSGSIZE;
1775
1776	if (ct_info->commit && nla_put_flag(skb, ct_info->force
1777					    ? OVS_CT_ATTR_FORCE_COMMIT
1778					    : OVS_CT_ATTR_COMMIT))
1779		return -EMSGSIZE;
1780	if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1781	    nla_put_u16(skb, OVS_CT_ATTR_ZONE, ct_info->zone.id))
1782		return -EMSGSIZE;
1783	if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && ct_info->mark.mask &&
1784	    nla_put(skb, OVS_CT_ATTR_MARK, sizeof(ct_info->mark),
1785		    &ct_info->mark))
1786		return -EMSGSIZE;
1787	if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1788	    labels_nonzero(&ct_info->labels.mask) &&
1789	    nla_put(skb, OVS_CT_ATTR_LABELS, sizeof(ct_info->labels),
1790		    &ct_info->labels))
1791		return -EMSGSIZE;
1792	if (ct_info->helper) {
1793		if (nla_put_string(skb, OVS_CT_ATTR_HELPER,
1794				   ct_info->helper->name))
1795			return -EMSGSIZE;
1796	}
1797	if (ct_info->have_eventmask &&
1798	    nla_put_u32(skb, OVS_CT_ATTR_EVENTMASK, ct_info->eventmask))
1799		return -EMSGSIZE;
1800	if (ct_info->timeout[0]) {
1801		if (nla_put_string(skb, OVS_CT_ATTR_TIMEOUT, ct_info->timeout))
1802			return -EMSGSIZE;
1803	}
1804
1805#if IS_ENABLED(CONFIG_NF_NAT)
1806	if (ct_info->nat && !ovs_ct_nat_to_attr(ct_info, skb))
1807		return -EMSGSIZE;
1808#endif
1809	nla_nest_end(skb, start);
1810
1811	return 0;
1812}
1813
1814void ovs_ct_free_action(const struct nlattr *a)
1815{
1816	struct ovs_conntrack_info *ct_info = nla_data(a);
1817
1818	__ovs_ct_free_action(ct_info);
1819}
1820
1821static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info)
1822{
1823	if (ct_info->helper) {
1824#if IS_ENABLED(CONFIG_NF_NAT)
1825		if (ct_info->nat)
1826			nf_nat_helper_put(ct_info->helper);
1827#endif
1828		nf_conntrack_helper_put(ct_info->helper);
1829	}
1830	if (ct_info->ct) {
1831		if (ct_info->timeout[0])
1832			nf_ct_destroy_timeout(ct_info->ct);
 
1833		nf_ct_tmpl_free(ct_info->ct);
1834	}
1835}
1836
1837#if	IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
1838static int ovs_ct_limit_init(struct net *net, struct ovs_net *ovs_net)
1839{
1840	int i, err;
1841
1842	ovs_net->ct_limit_info = kmalloc(sizeof(*ovs_net->ct_limit_info),
1843					 GFP_KERNEL);
1844	if (!ovs_net->ct_limit_info)
1845		return -ENOMEM;
1846
1847	ovs_net->ct_limit_info->default_limit = OVS_CT_LIMIT_DEFAULT;
1848	ovs_net->ct_limit_info->limits =
1849		kmalloc_array(CT_LIMIT_HASH_BUCKETS, sizeof(struct hlist_head),
1850			      GFP_KERNEL);
1851	if (!ovs_net->ct_limit_info->limits) {
1852		kfree(ovs_net->ct_limit_info);
1853		return -ENOMEM;
1854	}
1855
1856	for (i = 0; i < CT_LIMIT_HASH_BUCKETS; i++)
1857		INIT_HLIST_HEAD(&ovs_net->ct_limit_info->limits[i]);
1858
1859	ovs_net->ct_limit_info->data =
1860		nf_conncount_init(net, NFPROTO_INET, sizeof(u32));
1861
1862	if (IS_ERR(ovs_net->ct_limit_info->data)) {
1863		err = PTR_ERR(ovs_net->ct_limit_info->data);
1864		kfree(ovs_net->ct_limit_info->limits);
1865		kfree(ovs_net->ct_limit_info);
1866		pr_err("openvswitch: failed to init nf_conncount %d\n", err);
1867		return err;
1868	}
1869	return 0;
1870}
1871
1872static void ovs_ct_limit_exit(struct net *net, struct ovs_net *ovs_net)
1873{
1874	const struct ovs_ct_limit_info *info = ovs_net->ct_limit_info;
1875	int i;
1876
1877	nf_conncount_destroy(net, NFPROTO_INET, info->data);
1878	for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) {
1879		struct hlist_head *head = &info->limits[i];
1880		struct ovs_ct_limit *ct_limit;
 
1881
1882		hlist_for_each_entry_rcu(ct_limit, head, hlist_node)
1883			kfree_rcu(ct_limit, rcu);
1884	}
1885	kfree(ovs_net->ct_limit_info->limits);
1886	kfree(ovs_net->ct_limit_info);
1887}
1888
1889static struct sk_buff *
1890ovs_ct_limit_cmd_reply_start(struct genl_info *info, u8 cmd,
1891			     struct ovs_header **ovs_reply_header)
1892{
1893	struct ovs_header *ovs_header = info->userhdr;
1894	struct sk_buff *skb;
1895
1896	skb = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1897	if (!skb)
1898		return ERR_PTR(-ENOMEM);
1899
1900	*ovs_reply_header = genlmsg_put(skb, info->snd_portid,
1901					info->snd_seq,
1902					&dp_ct_limit_genl_family, 0, cmd);
1903
1904	if (!*ovs_reply_header) {
1905		nlmsg_free(skb);
1906		return ERR_PTR(-EMSGSIZE);
1907	}
1908	(*ovs_reply_header)->dp_ifindex = ovs_header->dp_ifindex;
1909
1910	return skb;
1911}
1912
1913static bool check_zone_id(int zone_id, u16 *pzone)
1914{
1915	if (zone_id >= 0 && zone_id <= 65535) {
1916		*pzone = (u16)zone_id;
1917		return true;
1918	}
1919	return false;
1920}
1921
1922static int ovs_ct_limit_set_zone_limit(struct nlattr *nla_zone_limit,
1923				       struct ovs_ct_limit_info *info)
1924{
1925	struct ovs_zone_limit *zone_limit;
1926	int rem;
1927	u16 zone;
1928
1929	rem = NLA_ALIGN(nla_len(nla_zone_limit));
1930	zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit);
1931
1932	while (rem >= sizeof(*zone_limit)) {
1933		if (unlikely(zone_limit->zone_id ==
1934				OVS_ZONE_LIMIT_DEFAULT_ZONE)) {
1935			ovs_lock();
1936			info->default_limit = zone_limit->limit;
1937			ovs_unlock();
1938		} else if (unlikely(!check_zone_id(
1939				zone_limit->zone_id, &zone))) {
1940			OVS_NLERR(true, "zone id is out of range");
1941		} else {
1942			struct ovs_ct_limit *ct_limit;
1943
1944			ct_limit = kmalloc(sizeof(*ct_limit), GFP_KERNEL);
 
1945			if (!ct_limit)
1946				return -ENOMEM;
1947
1948			ct_limit->zone = zone;
1949			ct_limit->limit = zone_limit->limit;
1950
1951			ovs_lock();
1952			ct_limit_set(info, ct_limit);
1953			ovs_unlock();
1954		}
1955		rem -= NLA_ALIGN(sizeof(*zone_limit));
1956		zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit +
1957				NLA_ALIGN(sizeof(*zone_limit)));
1958	}
1959
1960	if (rem)
1961		OVS_NLERR(true, "set zone limit has %d unknown bytes", rem);
1962
1963	return 0;
1964}
1965
1966static int ovs_ct_limit_del_zone_limit(struct nlattr *nla_zone_limit,
1967				       struct ovs_ct_limit_info *info)
1968{
1969	struct ovs_zone_limit *zone_limit;
1970	int rem;
1971	u16 zone;
1972
1973	rem = NLA_ALIGN(nla_len(nla_zone_limit));
1974	zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit);
1975
1976	while (rem >= sizeof(*zone_limit)) {
1977		if (unlikely(zone_limit->zone_id ==
1978				OVS_ZONE_LIMIT_DEFAULT_ZONE)) {
1979			ovs_lock();
1980			info->default_limit = OVS_CT_LIMIT_DEFAULT;
1981			ovs_unlock();
1982		} else if (unlikely(!check_zone_id(
1983				zone_limit->zone_id, &zone))) {
1984			OVS_NLERR(true, "zone id is out of range");
1985		} else {
1986			ovs_lock();
1987			ct_limit_del(info, zone);
1988			ovs_unlock();
1989		}
1990		rem -= NLA_ALIGN(sizeof(*zone_limit));
1991		zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit +
1992				NLA_ALIGN(sizeof(*zone_limit)));
1993	}
1994
1995	if (rem)
1996		OVS_NLERR(true, "del zone limit has %d unknown bytes", rem);
1997
1998	return 0;
1999}
2000
2001static int ovs_ct_limit_get_default_limit(struct ovs_ct_limit_info *info,
2002					  struct sk_buff *reply)
2003{
2004	struct ovs_zone_limit zone_limit;
2005	int err;
2006
2007	zone_limit.zone_id = OVS_ZONE_LIMIT_DEFAULT_ZONE;
2008	zone_limit.limit = info->default_limit;
2009	err = nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit);
2010	if (err)
2011		return err;
2012
2013	return 0;
2014}
2015
2016static int __ovs_ct_limit_get_zone_limit(struct net *net,
2017					 struct nf_conncount_data *data,
2018					 u16 zone_id, u32 limit,
2019					 struct sk_buff *reply)
2020{
2021	struct nf_conntrack_zone ct_zone;
2022	struct ovs_zone_limit zone_limit;
2023	u32 conncount_key = zone_id;
2024
2025	zone_limit.zone_id = zone_id;
2026	zone_limit.limit = limit;
2027	nf_ct_zone_init(&ct_zone, zone_id, NF_CT_DEFAULT_ZONE_DIR, 0);
2028
2029	zone_limit.count = nf_conncount_count(net, data, &conncount_key, NULL,
2030					      &ct_zone);
2031	return nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit);
2032}
2033
2034static int ovs_ct_limit_get_zone_limit(struct net *net,
2035				       struct nlattr *nla_zone_limit,
2036				       struct ovs_ct_limit_info *info,
2037				       struct sk_buff *reply)
2038{
2039	struct ovs_zone_limit *zone_limit;
2040	int rem, err;
2041	u32 limit;
2042	u16 zone;
2043
2044	rem = NLA_ALIGN(nla_len(nla_zone_limit));
2045	zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit);
2046
2047	while (rem >= sizeof(*zone_limit)) {
2048		if (unlikely(zone_limit->zone_id ==
2049				OVS_ZONE_LIMIT_DEFAULT_ZONE)) {
2050			err = ovs_ct_limit_get_default_limit(info, reply);
2051			if (err)
2052				return err;
2053		} else if (unlikely(!check_zone_id(zone_limit->zone_id,
2054							&zone))) {
2055			OVS_NLERR(true, "zone id is out of range");
2056		} else {
2057			rcu_read_lock();
2058			limit = ct_limit_get(info, zone);
2059			rcu_read_unlock();
2060
2061			err = __ovs_ct_limit_get_zone_limit(
2062				net, info->data, zone, limit, reply);
2063			if (err)
2064				return err;
2065		}
2066		rem -= NLA_ALIGN(sizeof(*zone_limit));
2067		zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit +
2068				NLA_ALIGN(sizeof(*zone_limit)));
2069	}
2070
2071	if (rem)
2072		OVS_NLERR(true, "get zone limit has %d unknown bytes", rem);
2073
2074	return 0;
2075}
2076
2077static int ovs_ct_limit_get_all_zone_limit(struct net *net,
2078					   struct ovs_ct_limit_info *info,
2079					   struct sk_buff *reply)
2080{
2081	struct ovs_ct_limit *ct_limit;
2082	struct hlist_head *head;
2083	int i, err = 0;
2084
2085	err = ovs_ct_limit_get_default_limit(info, reply);
2086	if (err)
2087		return err;
2088
2089	rcu_read_lock();
2090	for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) {
2091		head = &info->limits[i];
2092		hlist_for_each_entry_rcu(ct_limit, head, hlist_node) {
2093			err = __ovs_ct_limit_get_zone_limit(net, info->data,
2094				ct_limit->zone, ct_limit->limit, reply);
2095			if (err)
2096				goto exit_err;
2097		}
2098	}
2099
2100exit_err:
2101	rcu_read_unlock();
2102	return err;
2103}
2104
2105static int ovs_ct_limit_cmd_set(struct sk_buff *skb, struct genl_info *info)
2106{
2107	struct nlattr **a = info->attrs;
2108	struct sk_buff *reply;
2109	struct ovs_header *ovs_reply_header;
2110	struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id);
2111	struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
2112	int err;
2113
2114	reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_SET,
2115					     &ovs_reply_header);
2116	if (IS_ERR(reply))
2117		return PTR_ERR(reply);
2118
2119	if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) {
2120		err = -EINVAL;
2121		goto exit_err;
2122	}
2123
2124	err = ovs_ct_limit_set_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT],
2125					  ct_limit_info);
2126	if (err)
2127		goto exit_err;
2128
2129	static_branch_enable(&ovs_ct_limit_enabled);
2130
2131	genlmsg_end(reply, ovs_reply_header);
2132	return genlmsg_reply(reply, info);
2133
2134exit_err:
2135	nlmsg_free(reply);
2136	return err;
2137}
2138
2139static int ovs_ct_limit_cmd_del(struct sk_buff *skb, struct genl_info *info)
2140{
2141	struct nlattr **a = info->attrs;
2142	struct sk_buff *reply;
2143	struct ovs_header *ovs_reply_header;
2144	struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id);
2145	struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
2146	int err;
2147
2148	reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_DEL,
2149					     &ovs_reply_header);
2150	if (IS_ERR(reply))
2151		return PTR_ERR(reply);
2152
2153	if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) {
2154		err = -EINVAL;
2155		goto exit_err;
2156	}
2157
2158	err = ovs_ct_limit_del_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT],
2159					  ct_limit_info);
2160	if (err)
2161		goto exit_err;
2162
2163	genlmsg_end(reply, ovs_reply_header);
2164	return genlmsg_reply(reply, info);
2165
2166exit_err:
2167	nlmsg_free(reply);
2168	return err;
2169}
2170
2171static int ovs_ct_limit_cmd_get(struct sk_buff *skb, struct genl_info *info)
2172{
2173	struct nlattr **a = info->attrs;
2174	struct nlattr *nla_reply;
2175	struct sk_buff *reply;
2176	struct ovs_header *ovs_reply_header;
2177	struct net *net = sock_net(skb->sk);
2178	struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2179	struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
2180	int err;
2181
2182	reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_GET,
2183					     &ovs_reply_header);
2184	if (IS_ERR(reply))
2185		return PTR_ERR(reply);
2186
2187	nla_reply = nla_nest_start_noflag(reply, OVS_CT_LIMIT_ATTR_ZONE_LIMIT);
2188	if (!nla_reply) {
2189		err = -EMSGSIZE;
2190		goto exit_err;
2191	}
2192
2193	if (a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) {
2194		err = ovs_ct_limit_get_zone_limit(
2195			net, a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], ct_limit_info,
2196			reply);
2197		if (err)
2198			goto exit_err;
2199	} else {
2200		err = ovs_ct_limit_get_all_zone_limit(net, ct_limit_info,
2201						      reply);
2202		if (err)
2203			goto exit_err;
2204	}
2205
2206	nla_nest_end(reply, nla_reply);
2207	genlmsg_end(reply, ovs_reply_header);
2208	return genlmsg_reply(reply, info);
2209
2210exit_err:
2211	nlmsg_free(reply);
2212	return err;
2213}
2214
2215static struct genl_ops ct_limit_genl_ops[] = {
2216	{ .cmd = OVS_CT_LIMIT_CMD_SET,
2217		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2218		.flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN
2219					   * privilege. */
 
2220		.doit = ovs_ct_limit_cmd_set,
2221	},
2222	{ .cmd = OVS_CT_LIMIT_CMD_DEL,
2223		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2224		.flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN
2225					   * privilege. */
 
2226		.doit = ovs_ct_limit_cmd_del,
2227	},
2228	{ .cmd = OVS_CT_LIMIT_CMD_GET,
2229		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2230		.flags = 0,		  /* OK for unprivileged users. */
2231		.doit = ovs_ct_limit_cmd_get,
2232	},
2233};
2234
2235static const struct genl_multicast_group ovs_ct_limit_multicast_group = {
2236	.name = OVS_CT_LIMIT_MCGROUP,
2237};
2238
2239struct genl_family dp_ct_limit_genl_family __ro_after_init = {
2240	.hdrsize = sizeof(struct ovs_header),
2241	.name = OVS_CT_LIMIT_FAMILY,
2242	.version = OVS_CT_LIMIT_VERSION,
2243	.maxattr = OVS_CT_LIMIT_ATTR_MAX,
2244	.policy = ct_limit_policy,
2245	.netnsok = true,
2246	.parallel_ops = true,
2247	.ops = ct_limit_genl_ops,
2248	.n_ops = ARRAY_SIZE(ct_limit_genl_ops),
 
2249	.mcgrps = &ovs_ct_limit_multicast_group,
2250	.n_mcgrps = 1,
2251	.module = THIS_MODULE,
2252};
2253#endif
2254
2255int ovs_ct_init(struct net *net)
2256{
2257	unsigned int n_bits = sizeof(struct ovs_key_ct_labels) * BITS_PER_BYTE;
2258	struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2259
2260	if (nf_connlabels_get(net, n_bits - 1)) {
2261		ovs_net->xt_label = false;
2262		OVS_NLERR(true, "Failed to set connlabel length");
2263	} else {
2264		ovs_net->xt_label = true;
2265	}
2266
2267#if	IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
2268	return ovs_ct_limit_init(net, ovs_net);
2269#else
2270	return 0;
2271#endif
2272}
2273
2274void ovs_ct_exit(struct net *net)
2275{
 
2276	struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2277
2278#if	IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
2279	ovs_ct_limit_exit(net, ovs_net);
2280#endif
2281
2282	if (ovs_net->xt_label)
2283		nf_connlabels_put(net);
2284}