1// SPDX-License-Identifier: GPL-2.0-only
   2#include <linux/kernel.h>
   3#include <linux/skbuff.h>
   4#include <linux/export.h>
   5#include <linux/ip.h>
   6#include <linux/ipv6.h>
   7#include <linux/if_vlan.h>
   8#include <linux/filter.h>
   9#include <net/dsa.h>
  10#include <net/dst_metadata.h>
  11#include <net/ip.h>
  12#include <net/ipv6.h>
  13#include <net/gre.h>
  14#include <net/pptp.h>
  15#include <net/tipc.h>
  16#include <linux/igmp.h>
  17#include <linux/icmp.h>
  18#include <linux/sctp.h>
  19#include <linux/dccp.h>
  20#include <linux/if_tunnel.h>
  21#include <linux/if_pppox.h>
  22#include <linux/ppp_defs.h>
  23#include <linux/stddef.h>
  24#include <linux/if_ether.h>
  25#include <linux/if_hsr.h>
  26#include <linux/mpls.h>
  27#include <linux/tcp.h>
  28#include <linux/ptp_classify.h>
  29#include <net/flow_dissector.h>
  30#include <net/pkt_cls.h>
  31#include <scsi/fc/fc_fcoe.h>
  32#include <uapi/linux/batadv_packet.h>
  33#include <linux/bpf.h>
  34#if IS_ENABLED(CONFIG_NF_CONNTRACK)
  35#include <net/netfilter/nf_conntrack_core.h>
  36#include <net/netfilter/nf_conntrack_labels.h>
  37#endif
  38#include <linux/bpf-netns.h>
  39
  40static void dissector_set_key(struct flow_dissector *flow_dissector,
  41			      enum flow_dissector_key_id key_id)
  42{
  43	flow_dissector->used_keys |= (1ULL << key_id);
  44}
  45
  46void skb_flow_dissector_init(struct flow_dissector *flow_dissector,
  47			     const struct flow_dissector_key *key,
  48			     unsigned int key_count)
  49{
  50	unsigned int i;
  51
  52	memset(flow_dissector, 0, sizeof(*flow_dissector));
  53
  54	for (i = 0; i < key_count; i++, key++) {
  55		/* User should make sure that every key target offset is within
  56		 * boundaries of unsigned short.
  57		 */
  58		BUG_ON(key->offset > USHRT_MAX);
  59		BUG_ON(dissector_uses_key(flow_dissector,
  60					  key->key_id));
  61
  62		dissector_set_key(flow_dissector, key->key_id);
  63		flow_dissector->offset[key->key_id] = key->offset;
  64	}
  65
  66	/* Ensure that the dissector always includes control and basic key.
  67	 * That way we are able to avoid handling lack of these in fast path.
  68	 */
  69	BUG_ON(!dissector_uses_key(flow_dissector,
  70				   FLOW_DISSECTOR_KEY_CONTROL));
  71	BUG_ON(!dissector_uses_key(flow_dissector,
  72				   FLOW_DISSECTOR_KEY_BASIC));
  73}
  74EXPORT_SYMBOL(skb_flow_dissector_init);
  75
  76#ifdef CONFIG_BPF_SYSCALL
  77int flow_dissector_bpf_prog_attach_check(struct net *net,
  78					 struct bpf_prog *prog)
  79{
  80	enum netns_bpf_attach_type type = NETNS_BPF_FLOW_DISSECTOR;
  81
  82	if (net == &init_net) {
  83		/* BPF flow dissector in the root namespace overrides
  84		 * any per-net-namespace one. When attaching to root,
  85		 * make sure we don't have any BPF program attached
  86		 * to the non-root namespaces.
  87		 */
  88		struct net *ns;
  89
  90		for_each_net(ns) {
  91			if (ns == &init_net)
  92				continue;
  93			if (rcu_access_pointer(ns->bpf.run_array[type]))
  94				return -EEXIST;
  95		}
  96	} else {
  97		/* Make sure root flow dissector is not attached
  98		 * when attaching to the non-root namespace.
  99		 */
 100		if (rcu_access_pointer(init_net.bpf.run_array[type]))
 101			return -EEXIST;
 102	}
 103
 104	return 0;
 105}
 106#endif /* CONFIG_BPF_SYSCALL */
 107
 108/**
 109 * __skb_flow_get_ports - extract the upper layer ports and return them
 110 * @skb: sk_buff to extract the ports from
 111 * @thoff: transport header offset
 112 * @ip_proto: protocol for which to get port offset
 113 * @data: raw buffer pointer to the packet, if NULL use skb->data
 114 * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
 115 *
 116 * The function will try to retrieve the ports at offset thoff + poff where poff
 117 * is the protocol port offset returned from proto_ports_offset
 118 */
 119__be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto,
 120			    const void *data, int hlen)
 121{
 122	int poff = proto_ports_offset(ip_proto);
 123
 124	if (!data) {
 125		data = skb->data;
 126		hlen = skb_headlen(skb);
 127	}
 128
 129	if (poff >= 0) {
 130		__be32 *ports, _ports;
 131
 132		ports = __skb_header_pointer(skb, thoff + poff,
 133					     sizeof(_ports), data, hlen, &_ports);
 134		if (ports)
 135			return *ports;
 136	}
 137
 138	return 0;
 139}
 140EXPORT_SYMBOL(__skb_flow_get_ports);
 141
 142static bool icmp_has_id(u8 type)
 143{
 144	switch (type) {
 145	case ICMP_ECHO:
 146	case ICMP_ECHOREPLY:
 147	case ICMP_TIMESTAMP:
 148	case ICMP_TIMESTAMPREPLY:
 149	case ICMPV6_ECHO_REQUEST:
 150	case ICMPV6_ECHO_REPLY:
 151		return true;
 152	}
 153
 154	return false;
 155}
 156
 157/**
 158 * skb_flow_get_icmp_tci - extract ICMP(6) Type, Code and Identifier fields
 159 * @skb: sk_buff to extract from
 160 * @key_icmp: struct flow_dissector_key_icmp to fill
 161 * @data: raw buffer pointer to the packet
 162 * @thoff: offset to extract at
 163 * @hlen: packet header length
 164 */
 165void skb_flow_get_icmp_tci(const struct sk_buff *skb,
 166			   struct flow_dissector_key_icmp *key_icmp,
 167			   const void *data, int thoff, int hlen)
 168{
 169	struct icmphdr *ih, _ih;
 170
 171	ih = __skb_header_pointer(skb, thoff, sizeof(_ih), data, hlen, &_ih);
 172	if (!ih)
 173		return;
 174
 175	key_icmp->type = ih->type;
 176	key_icmp->code = ih->code;
 177
 178	/* As we use 0 to signal that the Id field is not present,
 179	 * avoid confusion with packets without such field
 180	 */
 181	if (icmp_has_id(ih->type))
 182		key_icmp->id = ih->un.echo.id ? ntohs(ih->un.echo.id) : 1;
 183	else
 184		key_icmp->id = 0;
 185}
 186EXPORT_SYMBOL(skb_flow_get_icmp_tci);
 187
 188/* If FLOW_DISSECTOR_KEY_ICMP is set, dissect an ICMP packet
 189 * using skb_flow_get_icmp_tci().
 190 */
 191static void __skb_flow_dissect_icmp(const struct sk_buff *skb,
 192				    struct flow_dissector *flow_dissector,
 193				    void *target_container, const void *data,
 194				    int thoff, int hlen)
 195{
 196	struct flow_dissector_key_icmp *key_icmp;
 197
 198	if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ICMP))
 199		return;
 200
 201	key_icmp = skb_flow_dissector_target(flow_dissector,
 202					     FLOW_DISSECTOR_KEY_ICMP,
 203					     target_container);
 204
 205	skb_flow_get_icmp_tci(skb, key_icmp, data, thoff, hlen);
 206}
 207
 208static void __skb_flow_dissect_ah(const struct sk_buff *skb,
 209				  struct flow_dissector *flow_dissector,
 210				  void *target_container, const void *data,
 211				  int nhoff, int hlen)
 212{
 213	struct flow_dissector_key_ipsec *key_ah;
 214	struct ip_auth_hdr _hdr, *hdr;
 215
 216	if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IPSEC))
 217		return;
 218
 219	hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
 220	if (!hdr)
 221		return;
 222
 223	key_ah = skb_flow_dissector_target(flow_dissector,
 224					   FLOW_DISSECTOR_KEY_IPSEC,
 225					   target_container);
 226
 227	key_ah->spi = hdr->spi;
 228}
 229
 230static void __skb_flow_dissect_esp(const struct sk_buff *skb,
 231				   struct flow_dissector *flow_dissector,
 232				   void *target_container, const void *data,
 233				   int nhoff, int hlen)
 234{
 235	struct flow_dissector_key_ipsec *key_esp;
 236	struct ip_esp_hdr _hdr, *hdr;
 237
 238	if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IPSEC))
 239		return;
 240
 241	hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
 242	if (!hdr)
 243		return;
 244
 245	key_esp = skb_flow_dissector_target(flow_dissector,
 246					    FLOW_DISSECTOR_KEY_IPSEC,
 247					    target_container);
 248
 249	key_esp->spi = hdr->spi;
 250}
 251
 252static void __skb_flow_dissect_l2tpv3(const struct sk_buff *skb,
 253				      struct flow_dissector *flow_dissector,
 254				      void *target_container, const void *data,
 255				      int nhoff, int hlen)
 256{
 257	struct flow_dissector_key_l2tpv3 *key_l2tpv3;
 258	struct {
 259		__be32 session_id;
 260	} *hdr, _hdr;
 261
 262	if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_L2TPV3))
 263		return;
 264
 265	hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
 266	if (!hdr)
 267		return;
 268
 269	key_l2tpv3 = skb_flow_dissector_target(flow_dissector,
 270					       FLOW_DISSECTOR_KEY_L2TPV3,
 271					       target_container);
 272
 273	key_l2tpv3->session_id = hdr->session_id;
 274}
 275
 276void skb_flow_dissect_meta(const struct sk_buff *skb,
 277			   struct flow_dissector *flow_dissector,
 278			   void *target_container)
 279{
 280	struct flow_dissector_key_meta *meta;
 281
 282	if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_META))
 283		return;
 284
 285	meta = skb_flow_dissector_target(flow_dissector,
 286					 FLOW_DISSECTOR_KEY_META,
 287					 target_container);
 288	meta->ingress_ifindex = skb->skb_iif;
 289#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
 290	if (tc_skb_ext_tc_enabled()) {
 291		struct tc_skb_ext *ext;
 292
 293		ext = skb_ext_find(skb, TC_SKB_EXT);
 294		if (ext)
 295			meta->l2_miss = ext->l2_miss;
 296	}
 297#endif
 298}
 299EXPORT_SYMBOL(skb_flow_dissect_meta);
 300
 301static void
 302skb_flow_dissect_set_enc_control(enum flow_dissector_key_id type,
 303				 u32 ctrl_flags,
 304				 struct flow_dissector *flow_dissector,
 305				 void *target_container)
 306{
 307	struct flow_dissector_key_control *ctrl;
 308
 309	if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_CONTROL))
 310		return;
 311
 312	ctrl = skb_flow_dissector_target(flow_dissector,
 313					 FLOW_DISSECTOR_KEY_ENC_CONTROL,
 314					 target_container);
 315	ctrl->addr_type = type;
 316	ctrl->flags = ctrl_flags;
 317}
 318
 319void
 320skb_flow_dissect_ct(const struct sk_buff *skb,
 321		    struct flow_dissector *flow_dissector,
 322		    void *target_container, u16 *ctinfo_map,
 323		    size_t mapsize, bool post_ct, u16 zone)
 324{
 325#if IS_ENABLED(CONFIG_NF_CONNTRACK)
 326	struct flow_dissector_key_ct *key;
 327	enum ip_conntrack_info ctinfo;
 328	struct nf_conn_labels *cl;
 329	struct nf_conn *ct;
 330
 331	if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_CT))
 332		return;
 333
 334	ct = nf_ct_get(skb, &ctinfo);
 335	if (!ct && !post_ct)
 336		return;
 337
 338	key = skb_flow_dissector_target(flow_dissector,
 339					FLOW_DISSECTOR_KEY_CT,
 340					target_container);
 341
 342	if (!ct) {
 343		key->ct_state = TCA_FLOWER_KEY_CT_FLAGS_TRACKED |
 344				TCA_FLOWER_KEY_CT_FLAGS_INVALID;
 345		key->ct_zone = zone;
 346		return;
 347	}
 348
 349	if (ctinfo < mapsize)
 350		key->ct_state = ctinfo_map[ctinfo];
 351#if IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)
 352	key->ct_zone = ct->zone.id;
 353#endif
 354#if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
 355	key->ct_mark = READ_ONCE(ct->mark);
 356#endif
 357
 358	cl = nf_ct_labels_find(ct);
 359	if (cl)
 360		memcpy(key->ct_labels, cl->bits, sizeof(key->ct_labels));
 361#endif /* CONFIG_NF_CONNTRACK */
 362}
 363EXPORT_SYMBOL(skb_flow_dissect_ct);
 364
 365void
 366skb_flow_dissect_tunnel_info(const struct sk_buff *skb,
 367			     struct flow_dissector *flow_dissector,
 368			     void *target_container)
 369{
 370	struct ip_tunnel_info *info;
 371	struct ip_tunnel_key *key;
 372	u32 ctrl_flags = 0;
 373
 374	/* A quick check to see if there might be something to do. */
 375	if (!dissector_uses_key(flow_dissector,
 376				FLOW_DISSECTOR_KEY_ENC_KEYID) &&
 377	    !dissector_uses_key(flow_dissector,
 378				FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS) &&
 379	    !dissector_uses_key(flow_dissector,
 380				FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS) &&
 381	    !dissector_uses_key(flow_dissector,
 382				FLOW_DISSECTOR_KEY_ENC_CONTROL) &&
 383	    !dissector_uses_key(flow_dissector,
 384				FLOW_DISSECTOR_KEY_ENC_PORTS) &&
 385	    !dissector_uses_key(flow_dissector,
 386				FLOW_DISSECTOR_KEY_ENC_IP) &&
 387	    !dissector_uses_key(flow_dissector,
 388				FLOW_DISSECTOR_KEY_ENC_OPTS))
 389		return;
 390
 391	info = skb_tunnel_info(skb);
 392	if (!info)
 393		return;
 394
 395	key = &info->key;
 396
 397	if (test_bit(IP_TUNNEL_CSUM_BIT, key->tun_flags))
 398		ctrl_flags |= FLOW_DIS_F_TUNNEL_CSUM;
 399	if (test_bit(IP_TUNNEL_DONT_FRAGMENT_BIT, key->tun_flags))
 400		ctrl_flags |= FLOW_DIS_F_TUNNEL_DONT_FRAGMENT;
 401	if (test_bit(IP_TUNNEL_OAM_BIT, key->tun_flags))
 402		ctrl_flags |= FLOW_DIS_F_TUNNEL_OAM;
 403	if (test_bit(IP_TUNNEL_CRIT_OPT_BIT, key->tun_flags))
 404		ctrl_flags |= FLOW_DIS_F_TUNNEL_CRIT_OPT;
 405
 406	switch (ip_tunnel_info_af(info)) {
 407	case AF_INET:
 408		skb_flow_dissect_set_enc_control(FLOW_DISSECTOR_KEY_IPV4_ADDRS,
 409						 ctrl_flags, flow_dissector,
 410						 target_container);
 411		if (dissector_uses_key(flow_dissector,
 412				       FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS)) {
 413			struct flow_dissector_key_ipv4_addrs *ipv4;
 414
 415			ipv4 = skb_flow_dissector_target(flow_dissector,
 416							 FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS,
 417							 target_container);
 418			ipv4->src = key->u.ipv4.src;
 419			ipv4->dst = key->u.ipv4.dst;
 420		}
 421		break;
 422	case AF_INET6:
 423		skb_flow_dissect_set_enc_control(FLOW_DISSECTOR_KEY_IPV6_ADDRS,
 424						 ctrl_flags, flow_dissector,
 425						 target_container);
 426		if (dissector_uses_key(flow_dissector,
 427				       FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS)) {
 428			struct flow_dissector_key_ipv6_addrs *ipv6;
 429
 430			ipv6 = skb_flow_dissector_target(flow_dissector,
 431							 FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS,
 432							 target_container);
 433			ipv6->src = key->u.ipv6.src;
 434			ipv6->dst = key->u.ipv6.dst;
 435		}
 436		break;
 437	default:
 438		skb_flow_dissect_set_enc_control(0, ctrl_flags, flow_dissector,
 439						 target_container);
 440		break;
 441	}
 442
 443	if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_KEYID)) {
 444		struct flow_dissector_key_keyid *keyid;
 445
 446		keyid = skb_flow_dissector_target(flow_dissector,
 447						  FLOW_DISSECTOR_KEY_ENC_KEYID,
 448						  target_container);
 449		keyid->keyid = tunnel_id_to_key32(key->tun_id);
 450	}
 451
 452	if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_PORTS)) {
 453		struct flow_dissector_key_ports *tp;
 454
 455		tp = skb_flow_dissector_target(flow_dissector,
 456					       FLOW_DISSECTOR_KEY_ENC_PORTS,
 457					       target_container);
 458		tp->src = key->tp_src;
 459		tp->dst = key->tp_dst;
 460	}
 461
 462	if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_IP)) {
 463		struct flow_dissector_key_ip *ip;
 464
 465		ip = skb_flow_dissector_target(flow_dissector,
 466					       FLOW_DISSECTOR_KEY_ENC_IP,
 467					       target_container);
 468		ip->tos = key->tos;
 469		ip->ttl = key->ttl;
 470	}
 471
 472	if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_OPTS)) {
 473		struct flow_dissector_key_enc_opts *enc_opt;
 474		IP_TUNNEL_DECLARE_FLAGS(flags) = { };
 475		u32 val;
 476
 477		enc_opt = skb_flow_dissector_target(flow_dissector,
 478						    FLOW_DISSECTOR_KEY_ENC_OPTS,
 479						    target_container);
 480
 481		if (!info->options_len)
 482			return;
 483
 484		enc_opt->len = info->options_len;
 485		ip_tunnel_info_opts_get(enc_opt->data, info);
 486
 487		ip_tunnel_set_options_present(flags);
 488		ip_tunnel_flags_and(flags, info->key.tun_flags, flags);
 489
 490		val = find_next_bit(flags, __IP_TUNNEL_FLAG_NUM,
 491				    IP_TUNNEL_GENEVE_OPT_BIT);
 492		enc_opt->dst_opt_type = val < __IP_TUNNEL_FLAG_NUM ? val : 0;
 493	}
 494}
 495EXPORT_SYMBOL(skb_flow_dissect_tunnel_info);
 496
 497void skb_flow_dissect_hash(const struct sk_buff *skb,
 498			   struct flow_dissector *flow_dissector,
 499			   void *target_container)
 500{
 501	struct flow_dissector_key_hash *key;
 502
 503	if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_HASH))
 504		return;
 505
 506	key = skb_flow_dissector_target(flow_dissector,
 507					FLOW_DISSECTOR_KEY_HASH,
 508					target_container);
 509
 510	key->hash = skb_get_hash_raw(skb);
 511}
 512EXPORT_SYMBOL(skb_flow_dissect_hash);
 513
 514static enum flow_dissect_ret
 515__skb_flow_dissect_mpls(const struct sk_buff *skb,
 516			struct flow_dissector *flow_dissector,
 517			void *target_container, const void *data, int nhoff,
 518			int hlen, int lse_index, bool *entropy_label)
 519{
 520	struct mpls_label *hdr, _hdr;
 521	u32 entry, label, bos;
 522
 523	if (!dissector_uses_key(flow_dissector,
 524				FLOW_DISSECTOR_KEY_MPLS_ENTROPY) &&
 525	    !dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS))
 526		return FLOW_DISSECT_RET_OUT_GOOD;
 527
 528	if (lse_index >= FLOW_DIS_MPLS_MAX)
 529		return FLOW_DISSECT_RET_OUT_GOOD;
 530
 531	hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
 532				   hlen, &_hdr);
 533	if (!hdr)
 534		return FLOW_DISSECT_RET_OUT_BAD;
 535
 536	entry = ntohl(hdr->entry);
 537	label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
 538	bos = (entry & MPLS_LS_S_MASK) >> MPLS_LS_S_SHIFT;
 539
 540	if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS)) {
 541		struct flow_dissector_key_mpls *key_mpls;
 542		struct flow_dissector_mpls_lse *lse;
 543
 544		key_mpls = skb_flow_dissector_target(flow_dissector,
 545						     FLOW_DISSECTOR_KEY_MPLS,
 546						     target_container);
 547		lse = &key_mpls->ls[lse_index];
 548
 549		lse->mpls_ttl = (entry & MPLS_LS_TTL_MASK) >> MPLS_LS_TTL_SHIFT;
 550		lse->mpls_bos = bos;
 551		lse->mpls_tc = (entry & MPLS_LS_TC_MASK) >> MPLS_LS_TC_SHIFT;
 552		lse->mpls_label = label;
 553		dissector_set_mpls_lse(key_mpls, lse_index);
 554	}
 555
 556	if (*entropy_label &&
 557	    dissector_uses_key(flow_dissector,
 558			       FLOW_DISSECTOR_KEY_MPLS_ENTROPY)) {
 559		struct flow_dissector_key_keyid *key_keyid;
 560
 561		key_keyid = skb_flow_dissector_target(flow_dissector,
 562						      FLOW_DISSECTOR_KEY_MPLS_ENTROPY,
 563						      target_container);
 564		key_keyid->keyid = cpu_to_be32(label);
 565	}
 566
 567	*entropy_label = label == MPLS_LABEL_ENTROPY;
 568
 569	return bos ? FLOW_DISSECT_RET_OUT_GOOD : FLOW_DISSECT_RET_PROTO_AGAIN;
 570}
 571
 572static enum flow_dissect_ret
 573__skb_flow_dissect_arp(const struct sk_buff *skb,
 574		       struct flow_dissector *flow_dissector,
 575		       void *target_container, const void *data,
 576		       int nhoff, int hlen)
 577{
 578	struct flow_dissector_key_arp *key_arp;
 579	struct {
 580		unsigned char ar_sha[ETH_ALEN];
 581		unsigned char ar_sip[4];
 582		unsigned char ar_tha[ETH_ALEN];
 583		unsigned char ar_tip[4];
 584	} *arp_eth, _arp_eth;
 585	const struct arphdr *arp;
 586	struct arphdr _arp;
 587
 588	if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ARP))
 589		return FLOW_DISSECT_RET_OUT_GOOD;
 590
 591	arp = __skb_header_pointer(skb, nhoff, sizeof(_arp), data,
 592				   hlen, &_arp);
 593	if (!arp)
 594		return FLOW_DISSECT_RET_OUT_BAD;
 595
 596	if (arp->ar_hrd != htons(ARPHRD_ETHER) ||
 597	    arp->ar_pro != htons(ETH_P_IP) ||
 598	    arp->ar_hln != ETH_ALEN ||
 599	    arp->ar_pln != 4 ||
 600	    (arp->ar_op != htons(ARPOP_REPLY) &&
 601	     arp->ar_op != htons(ARPOP_REQUEST)))
 602		return FLOW_DISSECT_RET_OUT_BAD;
 603
 604	arp_eth = __skb_header_pointer(skb, nhoff + sizeof(_arp),
 605				       sizeof(_arp_eth), data,
 606				       hlen, &_arp_eth);
 607	if (!arp_eth)
 608		return FLOW_DISSECT_RET_OUT_BAD;
 609
 610	key_arp = skb_flow_dissector_target(flow_dissector,
 611					    FLOW_DISSECTOR_KEY_ARP,
 612					    target_container);
 613
 614	memcpy(&key_arp->sip, arp_eth->ar_sip, sizeof(key_arp->sip));
 615	memcpy(&key_arp->tip, arp_eth->ar_tip, sizeof(key_arp->tip));
 616
 617	/* Only store the lower byte of the opcode;
 618	 * this covers ARPOP_REPLY and ARPOP_REQUEST.
 619	 */
 620	key_arp->op = ntohs(arp->ar_op) & 0xff;
 621
 622	ether_addr_copy(key_arp->sha, arp_eth->ar_sha);
 623	ether_addr_copy(key_arp->tha, arp_eth->ar_tha);
 624
 625	return FLOW_DISSECT_RET_OUT_GOOD;
 626}
 627
 628static enum flow_dissect_ret
 629__skb_flow_dissect_cfm(const struct sk_buff *skb,
 630		       struct flow_dissector *flow_dissector,
 631		       void *target_container, const void *data,
 632		       int nhoff, int hlen)
 633{
 634	struct flow_dissector_key_cfm *key, *hdr, _hdr;
 635
 636	if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_CFM))
 637		return FLOW_DISSECT_RET_OUT_GOOD;
 638
 639	hdr = __skb_header_pointer(skb, nhoff, sizeof(*key), data, hlen, &_hdr);
 640	if (!hdr)
 641		return FLOW_DISSECT_RET_OUT_BAD;
 642
 643	key = skb_flow_dissector_target(flow_dissector, FLOW_DISSECTOR_KEY_CFM,
 644					target_container);
 645
 646	key->mdl_ver = hdr->mdl_ver;
 647	key->opcode = hdr->opcode;
 648
 649	return FLOW_DISSECT_RET_OUT_GOOD;
 650}
 651
 652static enum flow_dissect_ret
 653__skb_flow_dissect_gre(const struct sk_buff *skb,
 654		       struct flow_dissector_key_control *key_control,
 655		       struct flow_dissector *flow_dissector,
 656		       void *target_container, const void *data,
 657		       __be16 *p_proto, int *p_nhoff, int *p_hlen,
 658		       unsigned int flags)
 659{
 660	struct flow_dissector_key_keyid *key_keyid;
 661	struct gre_base_hdr *hdr, _hdr;
 662	int offset = 0;
 663	u16 gre_ver;
 664
 665	hdr = __skb_header_pointer(skb, *p_nhoff, sizeof(_hdr),
 666				   data, *p_hlen, &_hdr);
 667	if (!hdr)
 668		return FLOW_DISSECT_RET_OUT_BAD;
 669
 670	/* Only look inside GRE without routing */
 671	if (hdr->flags & GRE_ROUTING)
 672		return FLOW_DISSECT_RET_OUT_GOOD;
 673
 674	/* Only look inside GRE for version 0 and 1 */
 675	gre_ver = ntohs(hdr->flags & GRE_VERSION);
 676	if (gre_ver > 1)
 677		return FLOW_DISSECT_RET_OUT_GOOD;
 678
 679	*p_proto = hdr->protocol;
 680	if (gre_ver) {
 681		/* Version1 must be PPTP, and check the flags */
 682		if (!(*p_proto == GRE_PROTO_PPP && (hdr->flags & GRE_KEY)))
 683			return FLOW_DISSECT_RET_OUT_GOOD;
 684	}
 685
 686	offset += sizeof(struct gre_base_hdr);
 687
 688	if (hdr->flags & GRE_CSUM)
 689		offset += sizeof_field(struct gre_full_hdr, csum) +
 690			  sizeof_field(struct gre_full_hdr, reserved1);
 691
 692	if (hdr->flags & GRE_KEY) {
 693		const __be32 *keyid;
 694		__be32 _keyid;
 695
 696		keyid = __skb_header_pointer(skb, *p_nhoff + offset,
 697					     sizeof(_keyid),
 698					     data, *p_hlen, &_keyid);
 699		if (!keyid)
 700			return FLOW_DISSECT_RET_OUT_BAD;
 701
 702		if (dissector_uses_key(flow_dissector,
 703				       FLOW_DISSECTOR_KEY_GRE_KEYID)) {
 704			key_keyid = skb_flow_dissector_target(flow_dissector,
 705							      FLOW_DISSECTOR_KEY_GRE_KEYID,
 706							      target_container);
 707			if (gre_ver == 0)
 708				key_keyid->keyid = *keyid;
 709			else
 710				key_keyid->keyid = *keyid & GRE_PPTP_KEY_MASK;
 711		}
 712		offset += sizeof_field(struct gre_full_hdr, key);
 713	}
 714
 715	if (hdr->flags & GRE_SEQ)
 716		offset += sizeof_field(struct pptp_gre_header, seq);
 717
 718	if (gre_ver == 0) {
 719		if (*p_proto == htons(ETH_P_TEB)) {
 720			const struct ethhdr *eth;
 721			struct ethhdr _eth;
 722
 723			eth = __skb_header_pointer(skb, *p_nhoff + offset,
 724						   sizeof(_eth),
 725						   data, *p_hlen, &_eth);
 726			if (!eth)
 727				return FLOW_DISSECT_RET_OUT_BAD;
 728			*p_proto = eth->h_proto;
 729			offset += sizeof(*eth);
 730
 731			/* Cap headers that we access via pointers at the
 732			 * end of the Ethernet header as our maximum alignment
 733			 * at that point is only 2 bytes.
 734			 */
 735			if (NET_IP_ALIGN)
 736				*p_hlen = *p_nhoff + offset;
 737		}
 738	} else { /* version 1, must be PPTP */
 739		u8 _ppp_hdr[PPP_HDRLEN];
 740		u8 *ppp_hdr;
 741
 742		if (hdr->flags & GRE_ACK)
 743			offset += sizeof_field(struct pptp_gre_header, ack);
 744
 745		ppp_hdr = __skb_header_pointer(skb, *p_nhoff + offset,
 746					       sizeof(_ppp_hdr),
 747					       data, *p_hlen, _ppp_hdr);
 748		if (!ppp_hdr)
 749			return FLOW_DISSECT_RET_OUT_BAD;
 750
 751		switch (PPP_PROTOCOL(ppp_hdr)) {
 752		case PPP_IP:
 753			*p_proto = htons(ETH_P_IP);
 754			break;
 755		case PPP_IPV6:
 756			*p_proto = htons(ETH_P_IPV6);
 757			break;
 758		default:
 759			/* Could probably catch some more like MPLS */
 760			break;
 761		}
 762
 763		offset += PPP_HDRLEN;
 764	}
 765
 766	*p_nhoff += offset;
 767	key_control->flags |= FLOW_DIS_ENCAPSULATION;
 768	if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
 769		return FLOW_DISSECT_RET_OUT_GOOD;
 770
 771	return FLOW_DISSECT_RET_PROTO_AGAIN;
 772}
 773
 774/**
 775 * __skb_flow_dissect_batadv() - dissect batman-adv header
 776 * @skb: sk_buff to with the batman-adv header
 777 * @key_control: flow dissectors control key
 778 * @data: raw buffer pointer to the packet, if NULL use skb->data
 779 * @p_proto: pointer used to update the protocol to process next
 780 * @p_nhoff: pointer used to update inner network header offset
 781 * @hlen: packet header length
 782 * @flags: any combination of FLOW_DISSECTOR_F_*
 783 *
 784 * ETH_P_BATMAN packets are tried to be dissected. Only
 785 * &struct batadv_unicast packets are actually processed because they contain an
 786 * inner ethernet header and are usually followed by actual network header. This
 787 * allows the flow dissector to continue processing the packet.
 788 *
 789 * Return: FLOW_DISSECT_RET_PROTO_AGAIN when &struct batadv_unicast was found,
 790 *  FLOW_DISSECT_RET_OUT_GOOD when dissector should stop after encapsulation,
 791 *  otherwise FLOW_DISSECT_RET_OUT_BAD
 792 */
 793static enum flow_dissect_ret
 794__skb_flow_dissect_batadv(const struct sk_buff *skb,
 795			  struct flow_dissector_key_control *key_control,
 796			  const void *data, __be16 *p_proto, int *p_nhoff,
 797			  int hlen, unsigned int flags)
 798{
 799	struct {
 800		struct batadv_unicast_packet batadv_unicast;
 801		struct ethhdr eth;
 802	} *hdr, _hdr;
 803
 804	hdr = __skb_header_pointer(skb, *p_nhoff, sizeof(_hdr), data, hlen,
 805				   &_hdr);
 806	if (!hdr)
 807		return FLOW_DISSECT_RET_OUT_BAD;
 808
 809	if (hdr->batadv_unicast.version != BATADV_COMPAT_VERSION)
 810		return FLOW_DISSECT_RET_OUT_BAD;
 811
 812	if (hdr->batadv_unicast.packet_type != BATADV_UNICAST)
 813		return FLOW_DISSECT_RET_OUT_BAD;
 814
 815	*p_proto = hdr->eth.h_proto;
 816	*p_nhoff += sizeof(*hdr);
 817
 818	key_control->flags |= FLOW_DIS_ENCAPSULATION;
 819	if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
 820		return FLOW_DISSECT_RET_OUT_GOOD;
 821
 822	return FLOW_DISSECT_RET_PROTO_AGAIN;
 823}
 824
 825static void
 826__skb_flow_dissect_tcp(const struct sk_buff *skb,
 827		       struct flow_dissector *flow_dissector,
 828		       void *target_container, const void *data,
 829		       int thoff, int hlen)
 830{
 831	struct flow_dissector_key_tcp *key_tcp;
 832	struct tcphdr *th, _th;
 833
 834	if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_TCP))
 835		return;
 836
 837	th = __skb_header_pointer(skb, thoff, sizeof(_th), data, hlen, &_th);
 838	if (!th)
 839		return;
 840
 841	if (unlikely(__tcp_hdrlen(th) < sizeof(_th)))
 842		return;
 843
 844	key_tcp = skb_flow_dissector_target(flow_dissector,
 845					    FLOW_DISSECTOR_KEY_TCP,
 846					    target_container);
 847	key_tcp->flags = (*(__be16 *) &tcp_flag_word(th) & htons(0x0FFF));
 848}
 849
 850static void
 851__skb_flow_dissect_ports(const struct sk_buff *skb,
 852			 struct flow_dissector *flow_dissector,
 853			 void *target_container, const void *data,
 854			 int nhoff, u8 ip_proto, int hlen)
 855{
 856	struct flow_dissector_key_ports_range *key_ports_range = NULL;
 857	struct flow_dissector_key_ports *key_ports = NULL;
 858	__be32 ports;
 859
 860	if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS))
 861		key_ports = skb_flow_dissector_target(flow_dissector,
 862						      FLOW_DISSECTOR_KEY_PORTS,
 863						      target_container);
 864
 865	if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS_RANGE))
 866		key_ports_range = skb_flow_dissector_target(flow_dissector,
 867							    FLOW_DISSECTOR_KEY_PORTS_RANGE,
 868							    target_container);
 869
 870	if (!key_ports && !key_ports_range)
 871		return;
 872
 873	ports = __skb_flow_get_ports(skb, nhoff, ip_proto, data, hlen);
 874
 875	if (key_ports)
 876		key_ports->ports = ports;
 877
 878	if (key_ports_range)
 879		key_ports_range->tp.ports = ports;
 880}
 881
 882static void
 883__skb_flow_dissect_ipv4(const struct sk_buff *skb,
 884			struct flow_dissector *flow_dissector,
 885			void *target_container, const void *data,
 886			const struct iphdr *iph)
 887{
 888	struct flow_dissector_key_ip *key_ip;
 889
 890	if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
 891		return;
 892
 893	key_ip = skb_flow_dissector_target(flow_dissector,
 894					   FLOW_DISSECTOR_KEY_IP,
 895					   target_container);
 896	key_ip->tos = iph->tos;
 897	key_ip->ttl = iph->ttl;
 898}
 899
 900static void
 901__skb_flow_dissect_ipv6(const struct sk_buff *skb,
 902			struct flow_dissector *flow_dissector,
 903			void *target_container, const void *data,
 904			const struct ipv6hdr *iph)
 905{
 906	struct flow_dissector_key_ip *key_ip;
 907
 908	if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
 909		return;
 910
 911	key_ip = skb_flow_dissector_target(flow_dissector,
 912					   FLOW_DISSECTOR_KEY_IP,
 913					   target_container);
 914	key_ip->tos = ipv6_get_dsfield(iph);
 915	key_ip->ttl = iph->hop_limit;
 916}
 917
 918/* Maximum number of protocol headers that can be parsed in
 919 * __skb_flow_dissect
 920 */
 921#define MAX_FLOW_DISSECT_HDRS	15
 922
 923static bool skb_flow_dissect_allowed(int *num_hdrs)
 924{
 925	++*num_hdrs;
 926
 927	return (*num_hdrs <= MAX_FLOW_DISSECT_HDRS);
 928}
 929
 930static void __skb_flow_bpf_to_target(const struct bpf_flow_keys *flow_keys,
 931				     struct flow_dissector *flow_dissector,
 932				     void *target_container)
 933{
 934	struct flow_dissector_key_ports_range *key_ports_range = NULL;
 935	struct flow_dissector_key_ports *key_ports = NULL;
 936	struct flow_dissector_key_control *key_control;
 937	struct flow_dissector_key_basic *key_basic;
 938	struct flow_dissector_key_addrs *key_addrs;
 939	struct flow_dissector_key_tags *key_tags;
 940
 941	key_control = skb_flow_dissector_target(flow_dissector,
 942						FLOW_DISSECTOR_KEY_CONTROL,
 943						target_container);
 944	key_control->thoff = flow_keys->thoff;
 945	if (flow_keys->is_frag)
 946		key_control->flags |= FLOW_DIS_IS_FRAGMENT;
 947	if (flow_keys->is_first_frag)
 948		key_control->flags |= FLOW_DIS_FIRST_FRAG;
 949	if (flow_keys->is_encap)
 950		key_control->flags |= FLOW_DIS_ENCAPSULATION;
 951
 952	key_basic = skb_flow_dissector_target(flow_dissector,
 953					      FLOW_DISSECTOR_KEY_BASIC,
 954					      target_container);
 955	key_basic->n_proto = flow_keys->n_proto;
 956	key_basic->ip_proto = flow_keys->ip_proto;
 957
 958	if (flow_keys->addr_proto == ETH_P_IP &&
 959	    dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
 960		key_addrs = skb_flow_dissector_target(flow_dissector,
 961						      FLOW_DISSECTOR_KEY_IPV4_ADDRS,
 962						      target_container);
 963		key_addrs->v4addrs.src = flow_keys->ipv4_src;
 964		key_addrs->v4addrs.dst = flow_keys->ipv4_dst;
 965		key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
 966	} else if (flow_keys->addr_proto == ETH_P_IPV6 &&
 967		   dissector_uses_key(flow_dissector,
 968				      FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
 969		key_addrs = skb_flow_dissector_target(flow_dissector,
 970						      FLOW_DISSECTOR_KEY_IPV6_ADDRS,
 971						      target_container);
 972		memcpy(&key_addrs->v6addrs.src, &flow_keys->ipv6_src,
 973		       sizeof(key_addrs->v6addrs.src));
 974		memcpy(&key_addrs->v6addrs.dst, &flow_keys->ipv6_dst,
 975		       sizeof(key_addrs->v6addrs.dst));
 976		key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
 977	}
 978
 979	if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS)) {
 980		key_ports = skb_flow_dissector_target(flow_dissector,
 981						      FLOW_DISSECTOR_KEY_PORTS,
 982						      target_container);
 
 
 
 
 
 
 
 983		key_ports->src = flow_keys->sport;
 984		key_ports->dst = flow_keys->dport;
 985	}
 986	if (dissector_uses_key(flow_dissector,
 987			       FLOW_DISSECTOR_KEY_PORTS_RANGE)) {
 988		key_ports_range = skb_flow_dissector_target(flow_dissector,
 989							    FLOW_DISSECTOR_KEY_PORTS_RANGE,
 990							    target_container);
 991		key_ports_range->tp.src = flow_keys->sport;
 992		key_ports_range->tp.dst = flow_keys->dport;
 993	}
 994
 995	if (dissector_uses_key(flow_dissector,
 996			       FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
 997		key_tags = skb_flow_dissector_target(flow_dissector,
 998						     FLOW_DISSECTOR_KEY_FLOW_LABEL,
 999						     target_container);
1000		key_tags->flow_label = ntohl(flow_keys->flow_label);
1001	}
1002}
1003
1004u32 bpf_flow_dissect(struct bpf_prog *prog, struct bpf_flow_dissector *ctx,
1005		     __be16 proto, int nhoff, int hlen, unsigned int flags)
1006{
1007	struct bpf_flow_keys *flow_keys = ctx->flow_keys;
1008	u32 result;
1009
1010	/* Pass parameters to the BPF program */
1011	memset(flow_keys, 0, sizeof(*flow_keys));
1012	flow_keys->n_proto = proto;
1013	flow_keys->nhoff = nhoff;
1014	flow_keys->thoff = flow_keys->nhoff;
1015
1016	BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_PARSE_1ST_FRAG !=
1017		     (int)FLOW_DISSECTOR_F_PARSE_1ST_FRAG);
1018	BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL !=
1019		     (int)FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
1020	BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_STOP_AT_ENCAP !=
1021		     (int)FLOW_DISSECTOR_F_STOP_AT_ENCAP);
1022	flow_keys->flags = flags;
1023
1024	result = bpf_prog_run_pin_on_cpu(prog, ctx);
1025
1026	flow_keys->nhoff = clamp_t(u16, flow_keys->nhoff, nhoff, hlen);
1027	flow_keys->thoff = clamp_t(u16, flow_keys->thoff,
1028				   flow_keys->nhoff, hlen);
1029
1030	return result;
1031}
1032
1033static bool is_pppoe_ses_hdr_valid(const struct pppoe_hdr *hdr)
1034{
1035	return hdr->ver == 1 && hdr->type == 1 && hdr->code == 0;
1036}
1037
1038/**
1039 * __skb_flow_dissect - extract the flow_keys struct and return it
1040 * @net: associated network namespace, derived from @skb if NULL
1041 * @skb: sk_buff to extract the flow from, can be NULL if the rest are specified
1042 * @flow_dissector: list of keys to dissect
1043 * @target_container: target structure to put dissected values into
1044 * @data: raw buffer pointer to the packet, if NULL use skb->data
1045 * @proto: protocol for which to get the flow, if @data is NULL use skb->protocol
1046 * @nhoff: network header offset, if @data is NULL use skb_network_offset(skb)
1047 * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
1048 * @flags: flags that control the dissection process, e.g.
1049 *         FLOW_DISSECTOR_F_STOP_AT_ENCAP.
1050 *
1051 * The function will try to retrieve individual keys into target specified
1052 * by flow_dissector from either the skbuff or a raw buffer specified by the
1053 * rest parameters.
1054 *
1055 * Caller must take care of zeroing target container memory.
1056 */
1057bool __skb_flow_dissect(const struct net *net,
1058			const struct sk_buff *skb,
1059			struct flow_dissector *flow_dissector,
1060			void *target_container, const void *data,
1061			__be16 proto, int nhoff, int hlen, unsigned int flags)
1062{
1063	struct flow_dissector_key_control *key_control;
1064	struct flow_dissector_key_basic *key_basic;
1065	struct flow_dissector_key_addrs *key_addrs;
1066	struct flow_dissector_key_tags *key_tags;
1067	struct flow_dissector_key_vlan *key_vlan;
1068	enum flow_dissect_ret fdret;
1069	enum flow_dissector_key_id dissector_vlan = FLOW_DISSECTOR_KEY_MAX;
1070	bool mpls_el = false;
1071	int mpls_lse = 0;
1072	int num_hdrs = 0;
1073	u8 ip_proto = 0;
1074	bool ret;
1075
1076	if (!data) {
1077		data = skb->data;
1078		proto = skb_vlan_tag_present(skb) ?
1079			 skb->vlan_proto : skb->protocol;
1080		nhoff = skb_network_offset(skb);
1081		hlen = skb_headlen(skb);
1082#if IS_ENABLED(CONFIG_NET_DSA)
1083		if (unlikely(skb->dev && netdev_uses_dsa(skb->dev) &&
1084			     proto == htons(ETH_P_XDSA))) {
1085			struct metadata_dst *md_dst = skb_metadata_dst(skb);
1086			const struct dsa_device_ops *ops;
1087			int offset = 0;
1088
1089			ops = skb->dev->dsa_ptr->tag_ops;
1090			/* Only DSA header taggers break flow dissection */
1091			if (ops->needed_headroom &&
1092			    (!md_dst || md_dst->type != METADATA_HW_PORT_MUX)) {
1093				if (ops->flow_dissect)
1094					ops->flow_dissect(skb, &proto, &offset);
1095				else
1096					dsa_tag_generic_flow_dissect(skb,
1097								     &proto,
1098								     &offset);
1099				hlen -= offset;
1100				nhoff += offset;
1101			}
1102		}
1103#endif
1104	}
1105
1106	/* It is ensured by skb_flow_dissector_init() that control key will
1107	 * be always present.
1108	 */
1109	key_control = skb_flow_dissector_target(flow_dissector,
1110						FLOW_DISSECTOR_KEY_CONTROL,
1111						target_container);
1112
1113	/* It is ensured by skb_flow_dissector_init() that basic key will
1114	 * be always present.
1115	 */
1116	key_basic = skb_flow_dissector_target(flow_dissector,
1117					      FLOW_DISSECTOR_KEY_BASIC,
1118					      target_container);
1119
1120	rcu_read_lock();
1121
1122	if (skb) {
1123		if (!net) {
1124			if (skb->dev)
1125				net = dev_net_rcu(skb->dev);
1126			else if (skb->sk)
1127				net = sock_net(skb->sk);
1128		}
1129	}
1130
1131	DEBUG_NET_WARN_ON_ONCE(!net);
1132	if (net) {
1133		enum netns_bpf_attach_type type = NETNS_BPF_FLOW_DISSECTOR;
1134		struct bpf_prog_array *run_array;
1135
 
1136		run_array = rcu_dereference(init_net.bpf.run_array[type]);
1137		if (!run_array)
1138			run_array = rcu_dereference(net->bpf.run_array[type]);
1139
1140		if (run_array) {
1141			struct bpf_flow_keys flow_keys;
1142			struct bpf_flow_dissector ctx = {
1143				.flow_keys = &flow_keys,
1144				.data = data,
1145				.data_end = data + hlen,
1146			};
1147			__be16 n_proto = proto;
1148			struct bpf_prog *prog;
1149			u32 result;
1150
1151			if (skb) {
1152				ctx.skb = skb;
1153				/* we can't use 'proto' in the skb case
1154				 * because it might be set to skb->vlan_proto
1155				 * which has been pulled from the data
1156				 */
1157				n_proto = skb->protocol;
1158			}
1159
1160			prog = READ_ONCE(run_array->items[0].prog);
1161			result = bpf_flow_dissect(prog, &ctx, n_proto, nhoff,
1162						  hlen, flags);
1163			if (result != BPF_FLOW_DISSECTOR_CONTINUE) {
1164				__skb_flow_bpf_to_target(&flow_keys, flow_dissector,
1165							 target_container);
1166				rcu_read_unlock();
1167				return result == BPF_OK;
1168			}
1169		}
 
 
1170	}
1171
1172	rcu_read_unlock();
1173
1174	if (dissector_uses_key(flow_dissector,
1175			       FLOW_DISSECTOR_KEY_ETH_ADDRS)) {
1176		struct ethhdr *eth = eth_hdr(skb);
1177		struct flow_dissector_key_eth_addrs *key_eth_addrs;
1178
1179		key_eth_addrs = skb_flow_dissector_target(flow_dissector,
1180							  FLOW_DISSECTOR_KEY_ETH_ADDRS,
1181							  target_container);
1182		memcpy(key_eth_addrs, eth, sizeof(*key_eth_addrs));
1183	}
1184
1185	if (dissector_uses_key(flow_dissector,
1186			       FLOW_DISSECTOR_KEY_NUM_OF_VLANS)) {
1187		struct flow_dissector_key_num_of_vlans *key_num_of_vlans;
1188
1189		key_num_of_vlans = skb_flow_dissector_target(flow_dissector,
1190							     FLOW_DISSECTOR_KEY_NUM_OF_VLANS,
1191							     target_container);
1192		key_num_of_vlans->num_of_vlans = 0;
1193	}
1194
1195proto_again:
1196	fdret = FLOW_DISSECT_RET_CONTINUE;
1197
1198	switch (proto) {
1199	case htons(ETH_P_IP): {
1200		const struct iphdr *iph;
1201		struct iphdr _iph;
1202
1203		iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
1204		if (!iph || iph->ihl < 5) {
1205			fdret = FLOW_DISSECT_RET_OUT_BAD;
1206			break;
1207		}
1208
1209		nhoff += iph->ihl * 4;
1210
1211		ip_proto = iph->protocol;
1212
1213		if (dissector_uses_key(flow_dissector,
1214				       FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
1215			key_addrs = skb_flow_dissector_target(flow_dissector,
1216							      FLOW_DISSECTOR_KEY_IPV4_ADDRS,
1217							      target_container);
1218
1219			memcpy(&key_addrs->v4addrs.src, &iph->saddr,
1220			       sizeof(key_addrs->v4addrs.src));
1221			memcpy(&key_addrs->v4addrs.dst, &iph->daddr,
1222			       sizeof(key_addrs->v4addrs.dst));
1223			key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
1224		}
1225
1226		__skb_flow_dissect_ipv4(skb, flow_dissector,
1227					target_container, data, iph);
1228
1229		if (ip_is_fragment(iph)) {
1230			key_control->flags |= FLOW_DIS_IS_FRAGMENT;
1231
1232			if (iph->frag_off & htons(IP_OFFSET)) {
1233				fdret = FLOW_DISSECT_RET_OUT_GOOD;
1234				break;
1235			} else {
1236				key_control->flags |= FLOW_DIS_FIRST_FRAG;
1237				if (!(flags &
1238				      FLOW_DISSECTOR_F_PARSE_1ST_FRAG)) {
1239					fdret = FLOW_DISSECT_RET_OUT_GOOD;
1240					break;
1241				}
1242			}
1243		}
1244
1245		break;
1246	}
1247	case htons(ETH_P_IPV6): {
1248		const struct ipv6hdr *iph;
1249		struct ipv6hdr _iph;
1250
1251		iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
1252		if (!iph) {
1253			fdret = FLOW_DISSECT_RET_OUT_BAD;
1254			break;
1255		}
1256
1257		ip_proto = iph->nexthdr;
1258		nhoff += sizeof(struct ipv6hdr);
1259
1260		if (dissector_uses_key(flow_dissector,
1261				       FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
1262			key_addrs = skb_flow_dissector_target(flow_dissector,
1263							      FLOW_DISSECTOR_KEY_IPV6_ADDRS,
1264							      target_container);
1265
1266			memcpy(&key_addrs->v6addrs.src, &iph->saddr,
1267			       sizeof(key_addrs->v6addrs.src));
1268			memcpy(&key_addrs->v6addrs.dst, &iph->daddr,
1269			       sizeof(key_addrs->v6addrs.dst));
1270			key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
1271		}
1272
1273		if ((dissector_uses_key(flow_dissector,
1274					FLOW_DISSECTOR_KEY_FLOW_LABEL) ||
1275		     (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL)) &&
1276		    ip6_flowlabel(iph)) {
1277			__be32 flow_label = ip6_flowlabel(iph);
1278
1279			if (dissector_uses_key(flow_dissector,
1280					       FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
1281				key_tags = skb_flow_dissector_target(flow_dissector,
1282								     FLOW_DISSECTOR_KEY_FLOW_LABEL,
1283								     target_container);
1284				key_tags->flow_label = ntohl(flow_label);
1285			}
1286			if (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL) {
1287				fdret = FLOW_DISSECT_RET_OUT_GOOD;
1288				break;
1289			}
1290		}
1291
1292		__skb_flow_dissect_ipv6(skb, flow_dissector,
1293					target_container, data, iph);
1294
1295		break;
1296	}
1297	case htons(ETH_P_8021AD):
1298	case htons(ETH_P_8021Q): {
1299		const struct vlan_hdr *vlan = NULL;
1300		struct vlan_hdr _vlan;
1301		__be16 saved_vlan_tpid = proto;
1302
1303		if (dissector_vlan == FLOW_DISSECTOR_KEY_MAX &&
1304		    skb && skb_vlan_tag_present(skb)) {
1305			proto = skb->protocol;
1306		} else {
1307			vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan),
1308						    data, hlen, &_vlan);
1309			if (!vlan) {
1310				fdret = FLOW_DISSECT_RET_OUT_BAD;
1311				break;
1312			}
1313
1314			proto = vlan->h_vlan_encapsulated_proto;
1315			nhoff += sizeof(*vlan);
1316		}
1317
1318		if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_NUM_OF_VLANS) &&
1319		    !(key_control->flags & FLOW_DIS_ENCAPSULATION)) {
1320			struct flow_dissector_key_num_of_vlans *key_nvs;
1321
1322			key_nvs = skb_flow_dissector_target(flow_dissector,
1323							    FLOW_DISSECTOR_KEY_NUM_OF_VLANS,
1324							    target_container);
1325			key_nvs->num_of_vlans++;
1326		}
1327
1328		if (dissector_vlan == FLOW_DISSECTOR_KEY_MAX) {
1329			dissector_vlan = FLOW_DISSECTOR_KEY_VLAN;
1330		} else if (dissector_vlan == FLOW_DISSECTOR_KEY_VLAN) {
1331			dissector_vlan = FLOW_DISSECTOR_KEY_CVLAN;
1332		} else {
1333			fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1334			break;
1335		}
1336
1337		if (dissector_uses_key(flow_dissector, dissector_vlan)) {
1338			key_vlan = skb_flow_dissector_target(flow_dissector,
1339							     dissector_vlan,
1340							     target_container);
1341
1342			if (!vlan) {
1343				key_vlan->vlan_id = skb_vlan_tag_get_id(skb);
1344				key_vlan->vlan_priority = skb_vlan_tag_get_prio(skb);
1345			} else {
1346				key_vlan->vlan_id = ntohs(vlan->h_vlan_TCI) &
1347					VLAN_VID_MASK;
1348				key_vlan->vlan_priority =
1349					(ntohs(vlan->h_vlan_TCI) &
1350					 VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
1351			}
1352			key_vlan->vlan_tpid = saved_vlan_tpid;
1353			key_vlan->vlan_eth_type = proto;
1354		}
1355
1356		fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1357		break;
1358	}
1359	case htons(ETH_P_PPP_SES): {
1360		struct {
1361			struct pppoe_hdr hdr;
1362			__be16 proto;
1363		} *hdr, _hdr;
1364		u16 ppp_proto;
1365
1366		hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
1367		if (!hdr) {
1368			fdret = FLOW_DISSECT_RET_OUT_BAD;
1369			break;
1370		}
1371
1372		if (!is_pppoe_ses_hdr_valid(&hdr->hdr)) {
1373			fdret = FLOW_DISSECT_RET_OUT_BAD;
1374			break;
1375		}
1376
1377		/* least significant bit of the most significant octet
1378		 * indicates if protocol field was compressed
1379		 */
1380		ppp_proto = ntohs(hdr->proto);
1381		if (ppp_proto & 0x0100) {
1382			ppp_proto = ppp_proto >> 8;
1383			nhoff += PPPOE_SES_HLEN - 1;
1384		} else {
1385			nhoff += PPPOE_SES_HLEN;
1386		}
1387
1388		if (ppp_proto == PPP_IP) {
1389			proto = htons(ETH_P_IP);
1390			fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1391		} else if (ppp_proto == PPP_IPV6) {
1392			proto = htons(ETH_P_IPV6);
1393			fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1394		} else if (ppp_proto == PPP_MPLS_UC) {
1395			proto = htons(ETH_P_MPLS_UC);
1396			fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1397		} else if (ppp_proto == PPP_MPLS_MC) {
1398			proto = htons(ETH_P_MPLS_MC);
1399			fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1400		} else if (ppp_proto_is_valid(ppp_proto)) {
1401			fdret = FLOW_DISSECT_RET_OUT_GOOD;
1402		} else {
1403			fdret = FLOW_DISSECT_RET_OUT_BAD;
1404			break;
1405		}
1406
1407		if (dissector_uses_key(flow_dissector,
1408				       FLOW_DISSECTOR_KEY_PPPOE)) {
1409			struct flow_dissector_key_pppoe *key_pppoe;
1410
1411			key_pppoe = skb_flow_dissector_target(flow_dissector,
1412							      FLOW_DISSECTOR_KEY_PPPOE,
1413							      target_container);
1414			key_pppoe->session_id = hdr->hdr.sid;
1415			key_pppoe->ppp_proto = htons(ppp_proto);
1416			key_pppoe->type = htons(ETH_P_PPP_SES);
1417		}
1418		break;
1419	}
1420	case htons(ETH_P_TIPC): {
1421		struct tipc_basic_hdr *hdr, _hdr;
1422
1423		hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr),
1424					   data, hlen, &_hdr);
1425		if (!hdr) {
1426			fdret = FLOW_DISSECT_RET_OUT_BAD;
1427			break;
1428		}
1429
1430		if (dissector_uses_key(flow_dissector,
1431				       FLOW_DISSECTOR_KEY_TIPC)) {
1432			key_addrs = skb_flow_dissector_target(flow_dissector,
1433							      FLOW_DISSECTOR_KEY_TIPC,
1434							      target_container);
1435			key_addrs->tipckey.key = tipc_hdr_rps_key(hdr);
1436			key_control->addr_type = FLOW_DISSECTOR_KEY_TIPC;
1437		}
1438		fdret = FLOW_DISSECT_RET_OUT_GOOD;
1439		break;
1440	}
1441
1442	case htons(ETH_P_MPLS_UC):
1443	case htons(ETH_P_MPLS_MC):
1444		fdret = __skb_flow_dissect_mpls(skb, flow_dissector,
1445						target_container, data,
1446						nhoff, hlen, mpls_lse,
1447						&mpls_el);
1448		nhoff += sizeof(struct mpls_label);
1449		mpls_lse++;
1450		break;
1451	case htons(ETH_P_FCOE):
1452		if ((hlen - nhoff) < FCOE_HEADER_LEN) {
1453			fdret = FLOW_DISSECT_RET_OUT_BAD;
1454			break;
1455		}
1456
1457		nhoff += FCOE_HEADER_LEN;
1458		fdret = FLOW_DISSECT_RET_OUT_GOOD;
1459		break;
1460
1461	case htons(ETH_P_ARP):
1462	case htons(ETH_P_RARP):
1463		fdret = __skb_flow_dissect_arp(skb, flow_dissector,
1464					       target_container, data,
1465					       nhoff, hlen);
1466		break;
1467
1468	case htons(ETH_P_BATMAN):
1469		fdret = __skb_flow_dissect_batadv(skb, key_control, data,
1470						  &proto, &nhoff, hlen, flags);
1471		break;
1472
1473	case htons(ETH_P_1588): {
1474		struct ptp_header *hdr, _hdr;
1475
1476		hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
1477					   hlen, &_hdr);
1478		if (!hdr) {
1479			fdret = FLOW_DISSECT_RET_OUT_BAD;
1480			break;
1481		}
1482
1483		nhoff += sizeof(struct ptp_header);
1484		fdret = FLOW_DISSECT_RET_OUT_GOOD;
1485		break;
1486	}
1487
1488	case htons(ETH_P_PRP):
1489	case htons(ETH_P_HSR): {
1490		struct hsr_tag *hdr, _hdr;
1491
1492		hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen,
1493					   &_hdr);
1494		if (!hdr) {
1495			fdret = FLOW_DISSECT_RET_OUT_BAD;
1496			break;
1497		}
1498
1499		proto = hdr->encap_proto;
1500		nhoff += HSR_HLEN;
1501		fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1502		break;
1503	}
1504
1505	case htons(ETH_P_CFM):
1506		fdret = __skb_flow_dissect_cfm(skb, flow_dissector,
1507					       target_container, data,
1508					       nhoff, hlen);
1509		break;
1510
1511	default:
1512		fdret = FLOW_DISSECT_RET_OUT_BAD;
1513		break;
1514	}
1515
1516	/* Process result of proto processing */
1517	switch (fdret) {
1518	case FLOW_DISSECT_RET_OUT_GOOD:
1519		goto out_good;
1520	case FLOW_DISSECT_RET_PROTO_AGAIN:
1521		if (skb_flow_dissect_allowed(&num_hdrs))
1522			goto proto_again;
1523		goto out_good;
1524	case FLOW_DISSECT_RET_CONTINUE:
1525	case FLOW_DISSECT_RET_IPPROTO_AGAIN:
1526		break;
1527	case FLOW_DISSECT_RET_OUT_BAD:
1528	default:
1529		goto out_bad;
1530	}
1531
1532ip_proto_again:
1533	fdret = FLOW_DISSECT_RET_CONTINUE;
1534
1535	switch (ip_proto) {
1536	case IPPROTO_GRE:
1537		if (flags & FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP) {
1538			fdret = FLOW_DISSECT_RET_OUT_GOOD;
1539			break;
1540		}
1541
1542		fdret = __skb_flow_dissect_gre(skb, key_control, flow_dissector,
1543					       target_container, data,
1544					       &proto, &nhoff, &hlen, flags);
1545		break;
1546
1547	case NEXTHDR_HOP:
1548	case NEXTHDR_ROUTING:
1549	case NEXTHDR_DEST: {
1550		u8 _opthdr[2], *opthdr;
1551
1552		if (proto != htons(ETH_P_IPV6))
1553			break;
1554
1555		opthdr = __skb_header_pointer(skb, nhoff, sizeof(_opthdr),
1556					      data, hlen, &_opthdr);
1557		if (!opthdr) {
1558			fdret = FLOW_DISSECT_RET_OUT_BAD;
1559			break;
1560		}
1561
1562		ip_proto = opthdr[0];
1563		nhoff += (opthdr[1] + 1) << 3;
1564
1565		fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
1566		break;
1567	}
1568	case NEXTHDR_FRAGMENT: {
1569		struct frag_hdr _fh, *fh;
1570
1571		if (proto != htons(ETH_P_IPV6))
1572			break;
1573
1574		fh = __skb_header_pointer(skb, nhoff, sizeof(_fh),
1575					  data, hlen, &_fh);
1576
1577		if (!fh) {
1578			fdret = FLOW_DISSECT_RET_OUT_BAD;
1579			break;
1580		}
1581
1582		key_control->flags |= FLOW_DIS_IS_FRAGMENT;
1583
1584		nhoff += sizeof(_fh);
1585		ip_proto = fh->nexthdr;
1586
1587		if (!(fh->frag_off & htons(IP6_OFFSET))) {
1588			key_control->flags |= FLOW_DIS_FIRST_FRAG;
1589			if (flags & FLOW_DISSECTOR_F_PARSE_1ST_FRAG) {
1590				fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
1591				break;
1592			}
1593		}
1594
1595		fdret = FLOW_DISSECT_RET_OUT_GOOD;
1596		break;
1597	}
1598	case IPPROTO_IPIP:
1599		if (flags & FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP) {
1600			fdret = FLOW_DISSECT_RET_OUT_GOOD;
1601			break;
1602		}
1603
1604		proto = htons(ETH_P_IP);
1605
1606		key_control->flags |= FLOW_DIS_ENCAPSULATION;
1607		if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
1608			fdret = FLOW_DISSECT_RET_OUT_GOOD;
1609			break;
1610		}
1611
1612		fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1613		break;
1614
1615	case IPPROTO_IPV6:
1616		if (flags & FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP) {
1617			fdret = FLOW_DISSECT_RET_OUT_GOOD;
1618			break;
1619		}
1620
1621		proto = htons(ETH_P_IPV6);
1622
1623		key_control->flags |= FLOW_DIS_ENCAPSULATION;
1624		if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
1625			fdret = FLOW_DISSECT_RET_OUT_GOOD;
1626			break;
1627		}
1628
1629		fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1630		break;
1631
1632
1633	case IPPROTO_MPLS:
1634		proto = htons(ETH_P_MPLS_UC);
1635		fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1636		break;
1637
1638	case IPPROTO_TCP:
1639		__skb_flow_dissect_tcp(skb, flow_dissector, target_container,
1640				       data, nhoff, hlen);
1641		break;
1642
1643	case IPPROTO_ICMP:
1644	case IPPROTO_ICMPV6:
1645		__skb_flow_dissect_icmp(skb, flow_dissector, target_container,
1646					data, nhoff, hlen);
1647		break;
1648	case IPPROTO_L2TP:
1649		__skb_flow_dissect_l2tpv3(skb, flow_dissector, target_container,
1650					  data, nhoff, hlen);
1651		break;
1652	case IPPROTO_ESP:
1653		__skb_flow_dissect_esp(skb, flow_dissector, target_container,
1654				       data, nhoff, hlen);
1655		break;
1656	case IPPROTO_AH:
1657		__skb_flow_dissect_ah(skb, flow_dissector, target_container,
1658				      data, nhoff, hlen);
1659		break;
1660	default:
1661		break;
1662	}
1663
1664	if (!(key_control->flags & FLOW_DIS_IS_FRAGMENT))
1665		__skb_flow_dissect_ports(skb, flow_dissector, target_container,
1666					 data, nhoff, ip_proto, hlen);
1667
1668	/* Process result of IP proto processing */
1669	switch (fdret) {
1670	case FLOW_DISSECT_RET_PROTO_AGAIN:
1671		if (skb_flow_dissect_allowed(&num_hdrs))
1672			goto proto_again;
1673		break;
1674	case FLOW_DISSECT_RET_IPPROTO_AGAIN:
1675		if (skb_flow_dissect_allowed(&num_hdrs))
1676			goto ip_proto_again;
1677		break;
1678	case FLOW_DISSECT_RET_OUT_GOOD:
1679	case FLOW_DISSECT_RET_CONTINUE:
1680		break;
1681	case FLOW_DISSECT_RET_OUT_BAD:
1682	default:
1683		goto out_bad;
1684	}
1685
1686out_good:
1687	ret = true;
1688
1689out:
1690	key_control->thoff = min_t(u16, nhoff, skb ? skb->len : hlen);
1691	key_basic->n_proto = proto;
1692	key_basic->ip_proto = ip_proto;
1693
1694	return ret;
1695
1696out_bad:
1697	ret = false;
1698	goto out;
1699}
1700EXPORT_SYMBOL(__skb_flow_dissect);
1701
1702static siphash_aligned_key_t hashrnd;
1703static __always_inline void __flow_hash_secret_init(void)
1704{
1705	net_get_random_once(&hashrnd, sizeof(hashrnd));
1706}
1707
1708static const void *flow_keys_hash_start(const struct flow_keys *flow)
1709{
1710	BUILD_BUG_ON(FLOW_KEYS_HASH_OFFSET % SIPHASH_ALIGNMENT);
1711	return &flow->FLOW_KEYS_HASH_START_FIELD;
1712}
1713
1714static inline size_t flow_keys_hash_length(const struct flow_keys *flow)
1715{
1716	size_t diff = FLOW_KEYS_HASH_OFFSET + sizeof(flow->addrs);
1717
1718	BUILD_BUG_ON((sizeof(*flow) - FLOW_KEYS_HASH_OFFSET) % sizeof(u32));
1719
1720	switch (flow->control.addr_type) {
1721	case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1722		diff -= sizeof(flow->addrs.v4addrs);
1723		break;
1724	case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1725		diff -= sizeof(flow->addrs.v6addrs);
1726		break;
1727	case FLOW_DISSECTOR_KEY_TIPC:
1728		diff -= sizeof(flow->addrs.tipckey);
1729		break;
1730	}
1731	return sizeof(*flow) - diff;
1732}
1733
1734__be32 flow_get_u32_src(const struct flow_keys *flow)
1735{
1736	switch (flow->control.addr_type) {
1737	case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1738		return flow->addrs.v4addrs.src;
1739	case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1740		return (__force __be32)ipv6_addr_hash(
1741			&flow->addrs.v6addrs.src);
1742	case FLOW_DISSECTOR_KEY_TIPC:
1743		return flow->addrs.tipckey.key;
1744	default:
1745		return 0;
1746	}
1747}
1748EXPORT_SYMBOL(flow_get_u32_src);
1749
1750__be32 flow_get_u32_dst(const struct flow_keys *flow)
1751{
1752	switch (flow->control.addr_type) {
1753	case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1754		return flow->addrs.v4addrs.dst;
1755	case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1756		return (__force __be32)ipv6_addr_hash(
1757			&flow->addrs.v6addrs.dst);
1758	default:
1759		return 0;
1760	}
1761}
1762EXPORT_SYMBOL(flow_get_u32_dst);
1763
1764/* Sort the source and destination IP and the ports,
1765 * to have consistent hash within the two directions
1766 */
1767static inline void __flow_hash_consistentify(struct flow_keys *keys)
1768{
1769	int addr_diff, i;
1770
1771	switch (keys->control.addr_type) {
1772	case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1773		if ((__force u32)keys->addrs.v4addrs.dst <
1774		    (__force u32)keys->addrs.v4addrs.src)
1775			swap(keys->addrs.v4addrs.src, keys->addrs.v4addrs.dst);
1776
1777		if ((__force u16)keys->ports.dst <
1778		    (__force u16)keys->ports.src) {
1779			swap(keys->ports.src, keys->ports.dst);
1780		}
1781		break;
1782	case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1783		addr_diff = memcmp(&keys->addrs.v6addrs.dst,
1784				   &keys->addrs.v6addrs.src,
1785				   sizeof(keys->addrs.v6addrs.dst));
1786		if (addr_diff < 0) {
1787			for (i = 0; i < 4; i++)
1788				swap(keys->addrs.v6addrs.src.s6_addr32[i],
1789				     keys->addrs.v6addrs.dst.s6_addr32[i]);
1790		}
1791		if ((__force u16)keys->ports.dst <
1792		    (__force u16)keys->ports.src) {
1793			swap(keys->ports.src, keys->ports.dst);
1794		}
1795		break;
1796	}
1797}
1798
1799static inline u32 __flow_hash_from_keys(struct flow_keys *keys,
1800					const siphash_key_t *keyval)
1801{
1802	u32 hash;
1803
1804	__flow_hash_consistentify(keys);
1805
1806	hash = siphash(flow_keys_hash_start(keys),
1807		       flow_keys_hash_length(keys), keyval);
1808	if (!hash)
1809		hash = 1;
1810
1811	return hash;
1812}
1813
1814u32 flow_hash_from_keys(struct flow_keys *keys)
1815{
1816	__flow_hash_secret_init();
1817	return __flow_hash_from_keys(keys, &hashrnd);
1818}
1819EXPORT_SYMBOL(flow_hash_from_keys);
1820
1821u32 flow_hash_from_keys_seed(struct flow_keys *keys,
1822			     const siphash_key_t *keyval)
1823{
1824	return __flow_hash_from_keys(keys, keyval);
1825}
1826EXPORT_SYMBOL(flow_hash_from_keys_seed);
1827
1828static inline u32 ___skb_get_hash(const struct sk_buff *skb,
1829				  struct flow_keys *keys,
1830				  const siphash_key_t *keyval)
1831{
1832	skb_flow_dissect_flow_keys(skb, keys,
1833				   FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
1834
1835	return __flow_hash_from_keys(keys, keyval);
1836}
1837
1838struct _flow_keys_digest_data {
1839	__be16	n_proto;
1840	u8	ip_proto;
1841	u8	padding;
1842	__be32	ports;
1843	__be32	src;
1844	__be32	dst;
1845};
1846
1847void make_flow_keys_digest(struct flow_keys_digest *digest,
1848			   const struct flow_keys *flow)
1849{
1850	struct _flow_keys_digest_data *data =
1851	    (struct _flow_keys_digest_data *)digest;
1852
1853	BUILD_BUG_ON(sizeof(*data) > sizeof(*digest));
1854
1855	memset(digest, 0, sizeof(*digest));
1856
1857	data->n_proto = flow->basic.n_proto;
1858	data->ip_proto = flow->basic.ip_proto;
1859	data->ports = flow->ports.ports;
1860	data->src = flow->addrs.v4addrs.src;
1861	data->dst = flow->addrs.v4addrs.dst;
1862}
1863EXPORT_SYMBOL(make_flow_keys_digest);
1864
1865static struct flow_dissector flow_keys_dissector_symmetric __read_mostly;
1866
1867u32 __skb_get_hash_symmetric_net(const struct net *net, const struct sk_buff *skb)
1868{
1869	struct flow_keys keys;
1870
1871	__flow_hash_secret_init();
1872
1873	memset(&keys, 0, sizeof(keys));
1874	__skb_flow_dissect(net, skb, &flow_keys_dissector_symmetric,
1875			   &keys, NULL, 0, 0, 0, 0);
 
1876
1877	return __flow_hash_from_keys(&keys, &hashrnd);
1878}
1879EXPORT_SYMBOL_GPL(__skb_get_hash_symmetric_net);
1880
1881/**
1882 * __skb_get_hash_net: calculate a flow hash
1883 * @net: associated network namespace, derived from @skb if NULL
1884 * @skb: sk_buff to calculate flow hash from
1885 *
1886 * This function calculates a flow hash based on src/dst addresses
1887 * and src/dst port numbers.  Sets hash in skb to non-zero hash value
1888 * on success, zero indicates no valid hash.  Also, sets l4_hash in skb
1889 * if hash is a canonical 4-tuple hash over transport ports.
1890 */
1891void __skb_get_hash_net(const struct net *net, struct sk_buff *skb)
1892{
1893	struct flow_keys keys;
1894	u32 hash;
1895
1896	memset(&keys, 0, sizeof(keys));
1897
1898	__skb_flow_dissect(net, skb, &flow_keys_dissector,
1899			   &keys, NULL, 0, 0, 0,
1900			   FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
1901
1902	__flow_hash_secret_init();
1903
1904	hash = __flow_hash_from_keys(&keys, &hashrnd);
1905
1906	__skb_set_sw_hash(skb, hash, flow_keys_have_l4(&keys));
1907}
1908EXPORT_SYMBOL(__skb_get_hash_net);
1909
1910__u32 skb_get_hash_perturb(const struct sk_buff *skb,
1911			   const siphash_key_t *perturb)
1912{
1913	struct flow_keys keys;
1914
1915	return ___skb_get_hash(skb, &keys, perturb);
1916}
1917EXPORT_SYMBOL(skb_get_hash_perturb);
1918
1919u32 __skb_get_poff(const struct sk_buff *skb, const void *data,
1920		   const struct flow_keys_basic *keys, int hlen)
1921{
1922	u32 poff = keys->control.thoff;
1923
1924	/* skip L4 headers for fragments after the first */
1925	if ((keys->control.flags & FLOW_DIS_IS_FRAGMENT) &&
1926	    !(keys->control.flags & FLOW_DIS_FIRST_FRAG))
1927		return poff;
1928
1929	switch (keys->basic.ip_proto) {
1930	case IPPROTO_TCP: {
1931		/* access doff as u8 to avoid unaligned access */
1932		const u8 *doff;
1933		u8 _doff;
1934
1935		doff = __skb_header_pointer(skb, poff + 12, sizeof(_doff),
1936					    data, hlen, &_doff);
1937		if (!doff)
1938			return poff;
1939
1940		poff += max_t(u32, sizeof(struct tcphdr), (*doff & 0xF0) >> 2);
1941		break;
1942	}
1943	case IPPROTO_UDP:
1944	case IPPROTO_UDPLITE:
1945		poff += sizeof(struct udphdr);
1946		break;
1947	/* For the rest, we do not really care about header
1948	 * extensions at this point for now.
1949	 */
1950	case IPPROTO_ICMP:
1951		poff += sizeof(struct icmphdr);
1952		break;
1953	case IPPROTO_ICMPV6:
1954		poff += sizeof(struct icmp6hdr);
1955		break;
1956	case IPPROTO_IGMP:
1957		poff += sizeof(struct igmphdr);
1958		break;
1959	case IPPROTO_DCCP:
1960		poff += sizeof(struct dccp_hdr);
1961		break;
1962	case IPPROTO_SCTP:
1963		poff += sizeof(struct sctphdr);
1964		break;
1965	}
1966
1967	return poff;
1968}
1969
1970/**
1971 * skb_get_poff - get the offset to the payload
1972 * @skb: sk_buff to get the payload offset from
1973 *
1974 * The function will get the offset to the payload as far as it could
1975 * be dissected.  The main user is currently BPF, so that we can dynamically
1976 * truncate packets without needing to push actual payload to the user
1977 * space and can analyze headers only, instead.
1978 */
1979u32 skb_get_poff(const struct sk_buff *skb)
1980{
1981	struct flow_keys_basic keys;
1982
1983	if (!skb_flow_dissect_flow_keys_basic(NULL, skb, &keys,
1984					      NULL, 0, 0, 0, 0))
1985		return 0;
1986
1987	return __skb_get_poff(skb, skb->data, &keys, skb_headlen(skb));
1988}
1989
1990__u32 __get_hash_from_flowi6(const struct flowi6 *fl6, struct flow_keys *keys)
1991{
1992	memset(keys, 0, sizeof(*keys));
1993
1994	memcpy(&keys->addrs.v6addrs.src, &fl6->saddr,
1995	    sizeof(keys->addrs.v6addrs.src));
1996	memcpy(&keys->addrs.v6addrs.dst, &fl6->daddr,
1997	    sizeof(keys->addrs.v6addrs.dst));
1998	keys->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
1999	keys->ports.src = fl6->fl6_sport;
2000	keys->ports.dst = fl6->fl6_dport;
2001	keys->keyid.keyid = fl6->fl6_gre_key;
2002	keys->tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);
2003	keys->basic.ip_proto = fl6->flowi6_proto;
2004
2005	return flow_hash_from_keys(keys);
2006}
2007EXPORT_SYMBOL(__get_hash_from_flowi6);
2008
2009static const struct flow_dissector_key flow_keys_dissector_keys[] = {
2010	{
2011		.key_id = FLOW_DISSECTOR_KEY_CONTROL,
2012		.offset = offsetof(struct flow_keys, control),
2013	},
2014	{
2015		.key_id = FLOW_DISSECTOR_KEY_BASIC,
2016		.offset = offsetof(struct flow_keys, basic),
2017	},
2018	{
2019		.key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
2020		.offset = offsetof(struct flow_keys, addrs.v4addrs),
2021	},
2022	{
2023		.key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
2024		.offset = offsetof(struct flow_keys, addrs.v6addrs),
2025	},
2026	{
2027		.key_id = FLOW_DISSECTOR_KEY_TIPC,
2028		.offset = offsetof(struct flow_keys, addrs.tipckey),
2029	},
2030	{
2031		.key_id = FLOW_DISSECTOR_KEY_PORTS,
2032		.offset = offsetof(struct flow_keys, ports),
2033	},
2034	{
2035		.key_id = FLOW_DISSECTOR_KEY_VLAN,
2036		.offset = offsetof(struct flow_keys, vlan),
2037	},
2038	{
2039		.key_id = FLOW_DISSECTOR_KEY_FLOW_LABEL,
2040		.offset = offsetof(struct flow_keys, tags),
2041	},
2042	{
2043		.key_id = FLOW_DISSECTOR_KEY_GRE_KEYID,
2044		.offset = offsetof(struct flow_keys, keyid),
2045	},
2046};
2047
2048static const struct flow_dissector_key flow_keys_dissector_symmetric_keys[] = {
2049	{
2050		.key_id = FLOW_DISSECTOR_KEY_CONTROL,
2051		.offset = offsetof(struct flow_keys, control),
2052	},
2053	{
2054		.key_id = FLOW_DISSECTOR_KEY_BASIC,
2055		.offset = offsetof(struct flow_keys, basic),
2056	},
2057	{
2058		.key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
2059		.offset = offsetof(struct flow_keys, addrs.v4addrs),
2060	},
2061	{
2062		.key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
2063		.offset = offsetof(struct flow_keys, addrs.v6addrs),
2064	},
2065	{
2066		.key_id = FLOW_DISSECTOR_KEY_PORTS,
2067		.offset = offsetof(struct flow_keys, ports),
2068	},
2069};
2070
2071static const struct flow_dissector_key flow_keys_basic_dissector_keys[] = {
2072	{
2073		.key_id = FLOW_DISSECTOR_KEY_CONTROL,
2074		.offset = offsetof(struct flow_keys, control),
2075	},
2076	{
2077		.key_id = FLOW_DISSECTOR_KEY_BASIC,
2078		.offset = offsetof(struct flow_keys, basic),
2079	},
2080};
2081
2082struct flow_dissector flow_keys_dissector __read_mostly;
2083EXPORT_SYMBOL(flow_keys_dissector);
2084
2085struct flow_dissector flow_keys_basic_dissector __read_mostly;
2086EXPORT_SYMBOL(flow_keys_basic_dissector);
2087
2088static int __init init_default_flow_dissectors(void)
2089{
2090	skb_flow_dissector_init(&flow_keys_dissector,
2091				flow_keys_dissector_keys,
2092				ARRAY_SIZE(flow_keys_dissector_keys));
2093	skb_flow_dissector_init(&flow_keys_dissector_symmetric,
2094				flow_keys_dissector_symmetric_keys,
2095				ARRAY_SIZE(flow_keys_dissector_symmetric_keys));
2096	skb_flow_dissector_init(&flow_keys_basic_dissector,
2097				flow_keys_basic_dissector_keys,
2098				ARRAY_SIZE(flow_keys_basic_dissector_keys));
2099	return 0;
2100}
2101core_initcall(init_default_flow_dissectors);