1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/kernel.h>
3 #include <linux/skbuff.h>
4 #include <linux/export.h>
6 #include <linux/ipv6.h>
7 #include <linux/if_vlan.h>
9 #include <net/dst_metadata.h>
15 #include <linux/igmp.h>
16 #include <linux/icmp.h>
17 #include <linux/sctp.h>
18 #include <linux/dccp.h>
19 #include <linux/if_tunnel.h>
20 #include <linux/if_pppox.h>
21 #include <linux/ppp_defs.h>
22 #include <linux/stddef.h>
23 #include <linux/if_ether.h>
24 #include <linux/mpls.h>
25 #include <linux/tcp.h>
26 #include <net/flow_dissector.h>
27 #include <scsi/fc/fc_fcoe.h>
28 #include <uapi/linux/batadv_packet.h>
29 #include <linux/bpf.h>
30 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
31 #include <net/netfilter/nf_conntrack_core.h>
32 #include <net/netfilter/nf_conntrack_labels.h>
35 static DEFINE_MUTEX(flow_dissector_mutex);
37 static void dissector_set_key(struct flow_dissector *flow_dissector,
38 enum flow_dissector_key_id key_id)
40 flow_dissector->used_keys |= (1 << key_id);
43 void skb_flow_dissector_init(struct flow_dissector *flow_dissector,
44 const struct flow_dissector_key *key,
45 unsigned int key_count)
49 memset(flow_dissector, 0, sizeof(*flow_dissector));
51 for (i = 0; i < key_count; i++, key++) {
52 /* User should make sure that every key target offset is withing
53 * boundaries of unsigned short.
55 BUG_ON(key->offset > USHRT_MAX);
56 BUG_ON(dissector_uses_key(flow_dissector,
59 dissector_set_key(flow_dissector, key->key_id);
60 flow_dissector->offset[key->key_id] = key->offset;
63 /* Ensure that the dissector always includes control and basic key.
64 * That way we are able to avoid handling lack of these in fast path.
66 BUG_ON(!dissector_uses_key(flow_dissector,
67 FLOW_DISSECTOR_KEY_CONTROL));
68 BUG_ON(!dissector_uses_key(flow_dissector,
69 FLOW_DISSECTOR_KEY_BASIC));
71 EXPORT_SYMBOL(skb_flow_dissector_init);
73 int skb_flow_dissector_prog_query(const union bpf_attr *attr,
74 union bpf_attr __user *uattr)
76 __u32 __user *prog_ids = u64_to_user_ptr(attr->query.prog_ids);
77 u32 prog_id, prog_cnt = 0, flags = 0;
78 struct bpf_prog *attached;
81 if (attr->query.query_flags)
84 net = get_net_ns_by_fd(attr->query.target_fd);
89 attached = rcu_dereference(net->flow_dissector_prog);
92 prog_id = attached->aux->id;
98 if (copy_to_user(&uattr->query.attach_flags, &flags, sizeof(flags)))
100 if (copy_to_user(&uattr->query.prog_cnt, &prog_cnt, sizeof(prog_cnt)))
103 if (!attr->query.prog_cnt || !prog_ids || !prog_cnt)
106 if (copy_to_user(prog_ids, &prog_id, sizeof(u32)))
112 int skb_flow_dissector_bpf_prog_attach(const union bpf_attr *attr,
113 struct bpf_prog *prog)
115 struct bpf_prog *attached;
118 net = current->nsproxy->net_ns;
119 mutex_lock(&flow_dissector_mutex);
120 attached = rcu_dereference_protected(net->flow_dissector_prog,
121 lockdep_is_held(&flow_dissector_mutex));
123 /* Only one BPF program can be attached at a time */
124 mutex_unlock(&flow_dissector_mutex);
127 rcu_assign_pointer(net->flow_dissector_prog, prog);
128 mutex_unlock(&flow_dissector_mutex);
132 int skb_flow_dissector_bpf_prog_detach(const union bpf_attr *attr)
134 struct bpf_prog *attached;
137 net = current->nsproxy->net_ns;
138 mutex_lock(&flow_dissector_mutex);
139 attached = rcu_dereference_protected(net->flow_dissector_prog,
140 lockdep_is_held(&flow_dissector_mutex));
142 mutex_unlock(&flow_dissector_mutex);
145 RCU_INIT_POINTER(net->flow_dissector_prog, NULL);
146 bpf_prog_put(attached);
147 mutex_unlock(&flow_dissector_mutex);
151 * skb_flow_get_be16 - extract be16 entity
152 * @skb: sk_buff to extract from
153 * @poff: offset to extract at
154 * @data: raw buffer pointer to the packet
155 * @hlen: packet header length
157 * The function will try to retrieve a be32 entity at
160 static __be16 skb_flow_get_be16(const struct sk_buff *skb, int poff,
161 void *data, int hlen)
165 u = __skb_header_pointer(skb, poff, sizeof(_u), data, hlen, &_u);
173 * __skb_flow_get_ports - extract the upper layer ports and return them
174 * @skb: sk_buff to extract the ports from
175 * @thoff: transport header offset
176 * @ip_proto: protocol for which to get port offset
177 * @data: raw buffer pointer to the packet, if NULL use skb->data
178 * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
180 * The function will try to retrieve the ports at offset thoff + poff where poff
181 * is the protocol port offset returned from proto_ports_offset
183 __be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto,
184 void *data, int hlen)
186 int poff = proto_ports_offset(ip_proto);
190 hlen = skb_headlen(skb);
194 __be32 *ports, _ports;
196 ports = __skb_header_pointer(skb, thoff + poff,
197 sizeof(_ports), data, hlen, &_ports);
204 EXPORT_SYMBOL(__skb_flow_get_ports);
206 void skb_flow_dissect_meta(const struct sk_buff *skb,
207 struct flow_dissector *flow_dissector,
208 void *target_container)
210 struct flow_dissector_key_meta *meta;
212 if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_META))
215 meta = skb_flow_dissector_target(flow_dissector,
216 FLOW_DISSECTOR_KEY_META,
218 meta->ingress_ifindex = skb->skb_iif;
220 EXPORT_SYMBOL(skb_flow_dissect_meta);
223 skb_flow_dissect_set_enc_addr_type(enum flow_dissector_key_id type,
224 struct flow_dissector *flow_dissector,
225 void *target_container)
227 struct flow_dissector_key_control *ctrl;
229 if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_CONTROL))
232 ctrl = skb_flow_dissector_target(flow_dissector,
233 FLOW_DISSECTOR_KEY_ENC_CONTROL,
235 ctrl->addr_type = type;
239 skb_flow_dissect_ct(const struct sk_buff *skb,
240 struct flow_dissector *flow_dissector,
241 void *target_container,
245 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
246 struct flow_dissector_key_ct *key;
247 enum ip_conntrack_info ctinfo;
248 struct nf_conn_labels *cl;
251 if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_CT))
254 ct = nf_ct_get(skb, &ctinfo);
258 key = skb_flow_dissector_target(flow_dissector,
259 FLOW_DISSECTOR_KEY_CT,
262 if (ctinfo < mapsize)
263 key->ct_state = ctinfo_map[ctinfo];
264 #if IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)
265 key->ct_zone = ct->zone.id;
267 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
268 key->ct_mark = ct->mark;
271 cl = nf_ct_labels_find(ct);
273 memcpy(key->ct_labels, cl->bits, sizeof(key->ct_labels));
274 #endif /* CONFIG_NF_CONNTRACK */
276 EXPORT_SYMBOL(skb_flow_dissect_ct);
279 skb_flow_dissect_tunnel_info(const struct sk_buff *skb,
280 struct flow_dissector *flow_dissector,
281 void *target_container)
283 struct ip_tunnel_info *info;
284 struct ip_tunnel_key *key;
286 /* A quick check to see if there might be something to do. */
287 if (!dissector_uses_key(flow_dissector,
288 FLOW_DISSECTOR_KEY_ENC_KEYID) &&
289 !dissector_uses_key(flow_dissector,
290 FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS) &&
291 !dissector_uses_key(flow_dissector,
292 FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS) &&
293 !dissector_uses_key(flow_dissector,
294 FLOW_DISSECTOR_KEY_ENC_CONTROL) &&
295 !dissector_uses_key(flow_dissector,
296 FLOW_DISSECTOR_KEY_ENC_PORTS) &&
297 !dissector_uses_key(flow_dissector,
298 FLOW_DISSECTOR_KEY_ENC_IP) &&
299 !dissector_uses_key(flow_dissector,
300 FLOW_DISSECTOR_KEY_ENC_OPTS))
303 info = skb_tunnel_info(skb);
309 switch (ip_tunnel_info_af(info)) {
311 skb_flow_dissect_set_enc_addr_type(FLOW_DISSECTOR_KEY_IPV4_ADDRS,
314 if (dissector_uses_key(flow_dissector,
315 FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS)) {
316 struct flow_dissector_key_ipv4_addrs *ipv4;
318 ipv4 = skb_flow_dissector_target(flow_dissector,
319 FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS,
321 ipv4->src = key->u.ipv4.src;
322 ipv4->dst = key->u.ipv4.dst;
326 skb_flow_dissect_set_enc_addr_type(FLOW_DISSECTOR_KEY_IPV6_ADDRS,
329 if (dissector_uses_key(flow_dissector,
330 FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS)) {
331 struct flow_dissector_key_ipv6_addrs *ipv6;
333 ipv6 = skb_flow_dissector_target(flow_dissector,
334 FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS,
336 ipv6->src = key->u.ipv6.src;
337 ipv6->dst = key->u.ipv6.dst;
342 if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_KEYID)) {
343 struct flow_dissector_key_keyid *keyid;
345 keyid = skb_flow_dissector_target(flow_dissector,
346 FLOW_DISSECTOR_KEY_ENC_KEYID,
348 keyid->keyid = tunnel_id_to_key32(key->tun_id);
351 if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_PORTS)) {
352 struct flow_dissector_key_ports *tp;
354 tp = skb_flow_dissector_target(flow_dissector,
355 FLOW_DISSECTOR_KEY_ENC_PORTS,
357 tp->src = key->tp_src;
358 tp->dst = key->tp_dst;
361 if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_IP)) {
362 struct flow_dissector_key_ip *ip;
364 ip = skb_flow_dissector_target(flow_dissector,
365 FLOW_DISSECTOR_KEY_ENC_IP,
371 if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_OPTS)) {
372 struct flow_dissector_key_enc_opts *enc_opt;
374 enc_opt = skb_flow_dissector_target(flow_dissector,
375 FLOW_DISSECTOR_KEY_ENC_OPTS,
378 if (info->options_len) {
379 enc_opt->len = info->options_len;
380 ip_tunnel_info_opts_get(enc_opt->data, info);
381 enc_opt->dst_opt_type = info->key.tun_flags &
382 TUNNEL_OPTIONS_PRESENT;
386 EXPORT_SYMBOL(skb_flow_dissect_tunnel_info);
388 static enum flow_dissect_ret
389 __skb_flow_dissect_mpls(const struct sk_buff *skb,
390 struct flow_dissector *flow_dissector,
391 void *target_container, void *data, int nhoff, int hlen)
393 struct flow_dissector_key_keyid *key_keyid;
394 struct mpls_label *hdr, _hdr[2];
397 if (!dissector_uses_key(flow_dissector,
398 FLOW_DISSECTOR_KEY_MPLS_ENTROPY) &&
399 !dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS))
400 return FLOW_DISSECT_RET_OUT_GOOD;
402 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
405 return FLOW_DISSECT_RET_OUT_BAD;
407 entry = ntohl(hdr[0].entry);
408 label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
410 if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS)) {
411 struct flow_dissector_key_mpls *key_mpls;
413 key_mpls = skb_flow_dissector_target(flow_dissector,
414 FLOW_DISSECTOR_KEY_MPLS,
416 key_mpls->mpls_label = label;
417 key_mpls->mpls_ttl = (entry & MPLS_LS_TTL_MASK)
418 >> MPLS_LS_TTL_SHIFT;
419 key_mpls->mpls_tc = (entry & MPLS_LS_TC_MASK)
421 key_mpls->mpls_bos = (entry & MPLS_LS_S_MASK)
425 if (label == MPLS_LABEL_ENTROPY) {
426 key_keyid = skb_flow_dissector_target(flow_dissector,
427 FLOW_DISSECTOR_KEY_MPLS_ENTROPY,
429 key_keyid->keyid = hdr[1].entry & htonl(MPLS_LS_LABEL_MASK);
431 return FLOW_DISSECT_RET_OUT_GOOD;
434 static enum flow_dissect_ret
435 __skb_flow_dissect_arp(const struct sk_buff *skb,
436 struct flow_dissector *flow_dissector,
437 void *target_container, void *data, int nhoff, int hlen)
439 struct flow_dissector_key_arp *key_arp;
441 unsigned char ar_sha[ETH_ALEN];
442 unsigned char ar_sip[4];
443 unsigned char ar_tha[ETH_ALEN];
444 unsigned char ar_tip[4];
445 } *arp_eth, _arp_eth;
446 const struct arphdr *arp;
449 if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ARP))
450 return FLOW_DISSECT_RET_OUT_GOOD;
452 arp = __skb_header_pointer(skb, nhoff, sizeof(_arp), data,
455 return FLOW_DISSECT_RET_OUT_BAD;
457 if (arp->ar_hrd != htons(ARPHRD_ETHER) ||
458 arp->ar_pro != htons(ETH_P_IP) ||
459 arp->ar_hln != ETH_ALEN ||
461 (arp->ar_op != htons(ARPOP_REPLY) &&
462 arp->ar_op != htons(ARPOP_REQUEST)))
463 return FLOW_DISSECT_RET_OUT_BAD;
465 arp_eth = __skb_header_pointer(skb, nhoff + sizeof(_arp),
466 sizeof(_arp_eth), data,
469 return FLOW_DISSECT_RET_OUT_BAD;
471 key_arp = skb_flow_dissector_target(flow_dissector,
472 FLOW_DISSECTOR_KEY_ARP,
475 memcpy(&key_arp->sip, arp_eth->ar_sip, sizeof(key_arp->sip));
476 memcpy(&key_arp->tip, arp_eth->ar_tip, sizeof(key_arp->tip));
478 /* Only store the lower byte of the opcode;
479 * this covers ARPOP_REPLY and ARPOP_REQUEST.
481 key_arp->op = ntohs(arp->ar_op) & 0xff;
483 ether_addr_copy(key_arp->sha, arp_eth->ar_sha);
484 ether_addr_copy(key_arp->tha, arp_eth->ar_tha);
486 return FLOW_DISSECT_RET_OUT_GOOD;
489 static enum flow_dissect_ret
490 __skb_flow_dissect_gre(const struct sk_buff *skb,
491 struct flow_dissector_key_control *key_control,
492 struct flow_dissector *flow_dissector,
493 void *target_container, void *data,
494 __be16 *p_proto, int *p_nhoff, int *p_hlen,
497 struct flow_dissector_key_keyid *key_keyid;
498 struct gre_base_hdr *hdr, _hdr;
502 hdr = __skb_header_pointer(skb, *p_nhoff, sizeof(_hdr),
503 data, *p_hlen, &_hdr);
505 return FLOW_DISSECT_RET_OUT_BAD;
507 /* Only look inside GRE without routing */
508 if (hdr->flags & GRE_ROUTING)
509 return FLOW_DISSECT_RET_OUT_GOOD;
511 /* Only look inside GRE for version 0 and 1 */
512 gre_ver = ntohs(hdr->flags & GRE_VERSION);
514 return FLOW_DISSECT_RET_OUT_GOOD;
516 *p_proto = hdr->protocol;
518 /* Version1 must be PPTP, and check the flags */
519 if (!(*p_proto == GRE_PROTO_PPP && (hdr->flags & GRE_KEY)))
520 return FLOW_DISSECT_RET_OUT_GOOD;
523 offset += sizeof(struct gre_base_hdr);
525 if (hdr->flags & GRE_CSUM)
526 offset += FIELD_SIZEOF(struct gre_full_hdr, csum) +
527 FIELD_SIZEOF(struct gre_full_hdr, reserved1);
529 if (hdr->flags & GRE_KEY) {
533 keyid = __skb_header_pointer(skb, *p_nhoff + offset,
535 data, *p_hlen, &_keyid);
537 return FLOW_DISSECT_RET_OUT_BAD;
539 if (dissector_uses_key(flow_dissector,
540 FLOW_DISSECTOR_KEY_GRE_KEYID)) {
541 key_keyid = skb_flow_dissector_target(flow_dissector,
542 FLOW_DISSECTOR_KEY_GRE_KEYID,
545 key_keyid->keyid = *keyid;
547 key_keyid->keyid = *keyid & GRE_PPTP_KEY_MASK;
549 offset += FIELD_SIZEOF(struct gre_full_hdr, key);
552 if (hdr->flags & GRE_SEQ)
553 offset += FIELD_SIZEOF(struct pptp_gre_header, seq);
556 if (*p_proto == htons(ETH_P_TEB)) {
557 const struct ethhdr *eth;
560 eth = __skb_header_pointer(skb, *p_nhoff + offset,
562 data, *p_hlen, &_eth);
564 return FLOW_DISSECT_RET_OUT_BAD;
565 *p_proto = eth->h_proto;
566 offset += sizeof(*eth);
568 /* Cap headers that we access via pointers at the
569 * end of the Ethernet header as our maximum alignment
570 * at that point is only 2 bytes.
573 *p_hlen = *p_nhoff + offset;
575 } else { /* version 1, must be PPTP */
576 u8 _ppp_hdr[PPP_HDRLEN];
579 if (hdr->flags & GRE_ACK)
580 offset += FIELD_SIZEOF(struct pptp_gre_header, ack);
582 ppp_hdr = __skb_header_pointer(skb, *p_nhoff + offset,
584 data, *p_hlen, _ppp_hdr);
586 return FLOW_DISSECT_RET_OUT_BAD;
588 switch (PPP_PROTOCOL(ppp_hdr)) {
590 *p_proto = htons(ETH_P_IP);
593 *p_proto = htons(ETH_P_IPV6);
596 /* Could probably catch some more like MPLS */
600 offset += PPP_HDRLEN;
604 key_control->flags |= FLOW_DIS_ENCAPSULATION;
605 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
606 return FLOW_DISSECT_RET_OUT_GOOD;
608 return FLOW_DISSECT_RET_PROTO_AGAIN;
612 * __skb_flow_dissect_batadv() - dissect batman-adv header
613 * @skb: sk_buff to with the batman-adv header
614 * @key_control: flow dissectors control key
615 * @data: raw buffer pointer to the packet, if NULL use skb->data
616 * @p_proto: pointer used to update the protocol to process next
617 * @p_nhoff: pointer used to update inner network header offset
618 * @hlen: packet header length
619 * @flags: any combination of FLOW_DISSECTOR_F_*
621 * ETH_P_BATMAN packets are tried to be dissected. Only
622 * &struct batadv_unicast packets are actually processed because they contain an
623 * inner ethernet header and are usually followed by actual network header. This
624 * allows the flow dissector to continue processing the packet.
626 * Return: FLOW_DISSECT_RET_PROTO_AGAIN when &struct batadv_unicast was found,
627 * FLOW_DISSECT_RET_OUT_GOOD when dissector should stop after encapsulation,
628 * otherwise FLOW_DISSECT_RET_OUT_BAD
630 static enum flow_dissect_ret
631 __skb_flow_dissect_batadv(const struct sk_buff *skb,
632 struct flow_dissector_key_control *key_control,
633 void *data, __be16 *p_proto, int *p_nhoff, int hlen,
637 struct batadv_unicast_packet batadv_unicast;
641 hdr = __skb_header_pointer(skb, *p_nhoff, sizeof(_hdr), data, hlen,
644 return FLOW_DISSECT_RET_OUT_BAD;
646 if (hdr->batadv_unicast.version != BATADV_COMPAT_VERSION)
647 return FLOW_DISSECT_RET_OUT_BAD;
649 if (hdr->batadv_unicast.packet_type != BATADV_UNICAST)
650 return FLOW_DISSECT_RET_OUT_BAD;
652 *p_proto = hdr->eth.h_proto;
653 *p_nhoff += sizeof(*hdr);
655 key_control->flags |= FLOW_DIS_ENCAPSULATION;
656 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
657 return FLOW_DISSECT_RET_OUT_GOOD;
659 return FLOW_DISSECT_RET_PROTO_AGAIN;
663 __skb_flow_dissect_tcp(const struct sk_buff *skb,
664 struct flow_dissector *flow_dissector,
665 void *target_container, void *data, int thoff, int hlen)
667 struct flow_dissector_key_tcp *key_tcp;
668 struct tcphdr *th, _th;
670 if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_TCP))
673 th = __skb_header_pointer(skb, thoff, sizeof(_th), data, hlen, &_th);
677 if (unlikely(__tcp_hdrlen(th) < sizeof(_th)))
680 key_tcp = skb_flow_dissector_target(flow_dissector,
681 FLOW_DISSECTOR_KEY_TCP,
683 key_tcp->flags = (*(__be16 *) &tcp_flag_word(th) & htons(0x0FFF));
687 __skb_flow_dissect_ipv4(const struct sk_buff *skb,
688 struct flow_dissector *flow_dissector,
689 void *target_container, void *data, const struct iphdr *iph)
691 struct flow_dissector_key_ip *key_ip;
693 if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
696 key_ip = skb_flow_dissector_target(flow_dissector,
697 FLOW_DISSECTOR_KEY_IP,
699 key_ip->tos = iph->tos;
700 key_ip->ttl = iph->ttl;
704 __skb_flow_dissect_ipv6(const struct sk_buff *skb,
705 struct flow_dissector *flow_dissector,
706 void *target_container, void *data, const struct ipv6hdr *iph)
708 struct flow_dissector_key_ip *key_ip;
710 if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
713 key_ip = skb_flow_dissector_target(flow_dissector,
714 FLOW_DISSECTOR_KEY_IP,
716 key_ip->tos = ipv6_get_dsfield(iph);
717 key_ip->ttl = iph->hop_limit;
720 /* Maximum number of protocol headers that can be parsed in
723 #define MAX_FLOW_DISSECT_HDRS 15
725 static bool skb_flow_dissect_allowed(int *num_hdrs)
729 return (*num_hdrs <= MAX_FLOW_DISSECT_HDRS);
732 static void __skb_flow_bpf_to_target(const struct bpf_flow_keys *flow_keys,
733 struct flow_dissector *flow_dissector,
734 void *target_container)
736 struct flow_dissector_key_control *key_control;
737 struct flow_dissector_key_basic *key_basic;
738 struct flow_dissector_key_addrs *key_addrs;
739 struct flow_dissector_key_ports *key_ports;
740 struct flow_dissector_key_tags *key_tags;
742 key_control = skb_flow_dissector_target(flow_dissector,
743 FLOW_DISSECTOR_KEY_CONTROL,
745 key_control->thoff = flow_keys->thoff;
746 if (flow_keys->is_frag)
747 key_control->flags |= FLOW_DIS_IS_FRAGMENT;
748 if (flow_keys->is_first_frag)
749 key_control->flags |= FLOW_DIS_FIRST_FRAG;
750 if (flow_keys->is_encap)
751 key_control->flags |= FLOW_DIS_ENCAPSULATION;
753 key_basic = skb_flow_dissector_target(flow_dissector,
754 FLOW_DISSECTOR_KEY_BASIC,
756 key_basic->n_proto = flow_keys->n_proto;
757 key_basic->ip_proto = flow_keys->ip_proto;
759 if (flow_keys->addr_proto == ETH_P_IP &&
760 dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
761 key_addrs = skb_flow_dissector_target(flow_dissector,
762 FLOW_DISSECTOR_KEY_IPV4_ADDRS,
764 key_addrs->v4addrs.src = flow_keys->ipv4_src;
765 key_addrs->v4addrs.dst = flow_keys->ipv4_dst;
766 key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
767 } else if (flow_keys->addr_proto == ETH_P_IPV6 &&
768 dissector_uses_key(flow_dissector,
769 FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
770 key_addrs = skb_flow_dissector_target(flow_dissector,
771 FLOW_DISSECTOR_KEY_IPV6_ADDRS,
773 memcpy(&key_addrs->v6addrs, &flow_keys->ipv6_src,
774 sizeof(key_addrs->v6addrs));
775 key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
778 if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS)) {
779 key_ports = skb_flow_dissector_target(flow_dissector,
780 FLOW_DISSECTOR_KEY_PORTS,
782 key_ports->src = flow_keys->sport;
783 key_ports->dst = flow_keys->dport;
786 if (dissector_uses_key(flow_dissector,
787 FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
788 key_tags = skb_flow_dissector_target(flow_dissector,
789 FLOW_DISSECTOR_KEY_FLOW_LABEL,
791 key_tags->flow_label = ntohl(flow_keys->flow_label);
795 bool bpf_flow_dissect(struct bpf_prog *prog, struct bpf_flow_dissector *ctx,
796 __be16 proto, int nhoff, int hlen, unsigned int flags)
798 struct bpf_flow_keys *flow_keys = ctx->flow_keys;
801 /* Pass parameters to the BPF program */
802 memset(flow_keys, 0, sizeof(*flow_keys));
803 flow_keys->n_proto = proto;
804 flow_keys->nhoff = nhoff;
805 flow_keys->thoff = flow_keys->nhoff;
807 BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_PARSE_1ST_FRAG !=
808 (int)FLOW_DISSECTOR_F_PARSE_1ST_FRAG);
809 BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL !=
810 (int)FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
811 BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_STOP_AT_ENCAP !=
812 (int)FLOW_DISSECTOR_F_STOP_AT_ENCAP);
813 flow_keys->flags = flags;
816 result = BPF_PROG_RUN(prog, ctx);
819 flow_keys->nhoff = clamp_t(u16, flow_keys->nhoff, nhoff, hlen);
820 flow_keys->thoff = clamp_t(u16, flow_keys->thoff,
821 flow_keys->nhoff, hlen);
823 return result == BPF_OK;
827 * __skb_flow_dissect - extract the flow_keys struct and return it
828 * @net: associated network namespace, derived from @skb if NULL
829 * @skb: sk_buff to extract the flow from, can be NULL if the rest are specified
830 * @flow_dissector: list of keys to dissect
831 * @target_container: target structure to put dissected values into
832 * @data: raw buffer pointer to the packet, if NULL use skb->data
833 * @proto: protocol for which to get the flow, if @data is NULL use skb->protocol
834 * @nhoff: network header offset, if @data is NULL use skb_network_offset(skb)
835 * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
836 * @flags: flags that control the dissection process, e.g.
837 * FLOW_DISSECTOR_F_STOP_AT_ENCAP.
839 * The function will try to retrieve individual keys into target specified
840 * by flow_dissector from either the skbuff or a raw buffer specified by the
843 * Caller must take care of zeroing target container memory.
845 bool __skb_flow_dissect(const struct net *net,
846 const struct sk_buff *skb,
847 struct flow_dissector *flow_dissector,
848 void *target_container,
849 void *data, __be16 proto, int nhoff, int hlen,
852 struct flow_dissector_key_control *key_control;
853 struct flow_dissector_key_basic *key_basic;
854 struct flow_dissector_key_addrs *key_addrs;
855 struct flow_dissector_key_ports *key_ports;
856 struct flow_dissector_key_icmp *key_icmp;
857 struct flow_dissector_key_tags *key_tags;
858 struct flow_dissector_key_vlan *key_vlan;
859 struct bpf_prog *attached = NULL;
860 enum flow_dissect_ret fdret;
861 enum flow_dissector_key_id dissector_vlan = FLOW_DISSECTOR_KEY_MAX;
868 proto = skb_vlan_tag_present(skb) ?
869 skb->vlan_proto : skb->protocol;
870 nhoff = skb_network_offset(skb);
871 hlen = skb_headlen(skb);
872 #if IS_ENABLED(CONFIG_NET_DSA)
873 if (unlikely(skb->dev && netdev_uses_dsa(skb->dev))) {
874 const struct dsa_device_ops *ops;
877 ops = skb->dev->dsa_ptr->tag_ops;
878 if (ops->flow_dissect &&
879 !ops->flow_dissect(skb, &proto, &offset)) {
887 /* It is ensured by skb_flow_dissector_init() that control key will
890 key_control = skb_flow_dissector_target(flow_dissector,
891 FLOW_DISSECTOR_KEY_CONTROL,
894 /* It is ensured by skb_flow_dissector_init() that basic key will
897 key_basic = skb_flow_dissector_target(flow_dissector,
898 FLOW_DISSECTOR_KEY_BASIC,
904 net = dev_net(skb->dev);
906 net = sock_net(skb->sk);
913 attached = rcu_dereference(net->flow_dissector_prog);
916 struct bpf_flow_keys flow_keys;
917 struct bpf_flow_dissector ctx = {
918 .flow_keys = &flow_keys,
920 .data_end = data + hlen,
922 __be16 n_proto = proto;
926 /* we can't use 'proto' in the skb case
927 * because it might be set to skb->vlan_proto
928 * which has been pulled from the data
930 n_proto = skb->protocol;
933 ret = bpf_flow_dissect(attached, &ctx, n_proto, nhoff,
935 __skb_flow_bpf_to_target(&flow_keys, flow_dissector,
943 if (dissector_uses_key(flow_dissector,
944 FLOW_DISSECTOR_KEY_ETH_ADDRS)) {
945 struct ethhdr *eth = eth_hdr(skb);
946 struct flow_dissector_key_eth_addrs *key_eth_addrs;
948 key_eth_addrs = skb_flow_dissector_target(flow_dissector,
949 FLOW_DISSECTOR_KEY_ETH_ADDRS,
951 memcpy(key_eth_addrs, ð->h_dest, sizeof(*key_eth_addrs));
955 fdret = FLOW_DISSECT_RET_CONTINUE;
958 case htons(ETH_P_IP): {
959 const struct iphdr *iph;
962 iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
963 if (!iph || iph->ihl < 5) {
964 fdret = FLOW_DISSECT_RET_OUT_BAD;
968 nhoff += iph->ihl * 4;
970 ip_proto = iph->protocol;
972 if (dissector_uses_key(flow_dissector,
973 FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
974 key_addrs = skb_flow_dissector_target(flow_dissector,
975 FLOW_DISSECTOR_KEY_IPV4_ADDRS,
978 memcpy(&key_addrs->v4addrs, &iph->saddr,
979 sizeof(key_addrs->v4addrs));
980 key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
983 if (ip_is_fragment(iph)) {
984 key_control->flags |= FLOW_DIS_IS_FRAGMENT;
986 if (iph->frag_off & htons(IP_OFFSET)) {
987 fdret = FLOW_DISSECT_RET_OUT_GOOD;
990 key_control->flags |= FLOW_DIS_FIRST_FRAG;
992 FLOW_DISSECTOR_F_PARSE_1ST_FRAG)) {
993 fdret = FLOW_DISSECT_RET_OUT_GOOD;
999 __skb_flow_dissect_ipv4(skb, flow_dissector,
1000 target_container, data, iph);
1004 case htons(ETH_P_IPV6): {
1005 const struct ipv6hdr *iph;
1006 struct ipv6hdr _iph;
1008 iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
1010 fdret = FLOW_DISSECT_RET_OUT_BAD;
1014 ip_proto = iph->nexthdr;
1015 nhoff += sizeof(struct ipv6hdr);
1017 if (dissector_uses_key(flow_dissector,
1018 FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
1019 key_addrs = skb_flow_dissector_target(flow_dissector,
1020 FLOW_DISSECTOR_KEY_IPV6_ADDRS,
1023 memcpy(&key_addrs->v6addrs, &iph->saddr,
1024 sizeof(key_addrs->v6addrs));
1025 key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
1028 if ((dissector_uses_key(flow_dissector,
1029 FLOW_DISSECTOR_KEY_FLOW_LABEL) ||
1030 (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL)) &&
1031 ip6_flowlabel(iph)) {
1032 __be32 flow_label = ip6_flowlabel(iph);
1034 if (dissector_uses_key(flow_dissector,
1035 FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
1036 key_tags = skb_flow_dissector_target(flow_dissector,
1037 FLOW_DISSECTOR_KEY_FLOW_LABEL,
1039 key_tags->flow_label = ntohl(flow_label);
1041 if (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL) {
1042 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1047 __skb_flow_dissect_ipv6(skb, flow_dissector,
1048 target_container, data, iph);
1052 case htons(ETH_P_8021AD):
1053 case htons(ETH_P_8021Q): {
1054 const struct vlan_hdr *vlan = NULL;
1055 struct vlan_hdr _vlan;
1056 __be16 saved_vlan_tpid = proto;
1058 if (dissector_vlan == FLOW_DISSECTOR_KEY_MAX &&
1059 skb && skb_vlan_tag_present(skb)) {
1060 proto = skb->protocol;
1062 vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan),
1063 data, hlen, &_vlan);
1065 fdret = FLOW_DISSECT_RET_OUT_BAD;
1069 proto = vlan->h_vlan_encapsulated_proto;
1070 nhoff += sizeof(*vlan);
1073 if (dissector_vlan == FLOW_DISSECTOR_KEY_MAX) {
1074 dissector_vlan = FLOW_DISSECTOR_KEY_VLAN;
1075 } else if (dissector_vlan == FLOW_DISSECTOR_KEY_VLAN) {
1076 dissector_vlan = FLOW_DISSECTOR_KEY_CVLAN;
1078 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1082 if (dissector_uses_key(flow_dissector, dissector_vlan)) {
1083 key_vlan = skb_flow_dissector_target(flow_dissector,
1088 key_vlan->vlan_id = skb_vlan_tag_get_id(skb);
1089 key_vlan->vlan_priority = skb_vlan_tag_get_prio(skb);
1091 key_vlan->vlan_id = ntohs(vlan->h_vlan_TCI) &
1093 key_vlan->vlan_priority =
1094 (ntohs(vlan->h_vlan_TCI) &
1095 VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
1097 key_vlan->vlan_tpid = saved_vlan_tpid;
1100 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1103 case htons(ETH_P_PPP_SES): {
1105 struct pppoe_hdr hdr;
1108 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
1110 fdret = FLOW_DISSECT_RET_OUT_BAD;
1115 nhoff += PPPOE_SES_HLEN;
1118 proto = htons(ETH_P_IP);
1119 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1121 case htons(PPP_IPV6):
1122 proto = htons(ETH_P_IPV6);
1123 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1126 fdret = FLOW_DISSECT_RET_OUT_BAD;
1131 case htons(ETH_P_TIPC): {
1132 struct tipc_basic_hdr *hdr, _hdr;
1134 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr),
1137 fdret = FLOW_DISSECT_RET_OUT_BAD;
1141 if (dissector_uses_key(flow_dissector,
1142 FLOW_DISSECTOR_KEY_TIPC)) {
1143 key_addrs = skb_flow_dissector_target(flow_dissector,
1144 FLOW_DISSECTOR_KEY_TIPC,
1146 key_addrs->tipckey.key = tipc_hdr_rps_key(hdr);
1147 key_control->addr_type = FLOW_DISSECTOR_KEY_TIPC;
1149 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1153 case htons(ETH_P_MPLS_UC):
1154 case htons(ETH_P_MPLS_MC):
1155 fdret = __skb_flow_dissect_mpls(skb, flow_dissector,
1156 target_container, data,
1159 case htons(ETH_P_FCOE):
1160 if ((hlen - nhoff) < FCOE_HEADER_LEN) {
1161 fdret = FLOW_DISSECT_RET_OUT_BAD;
1165 nhoff += FCOE_HEADER_LEN;
1166 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1169 case htons(ETH_P_ARP):
1170 case htons(ETH_P_RARP):
1171 fdret = __skb_flow_dissect_arp(skb, flow_dissector,
1172 target_container, data,
1176 case htons(ETH_P_BATMAN):
1177 fdret = __skb_flow_dissect_batadv(skb, key_control, data,
1178 &proto, &nhoff, hlen, flags);
1182 fdret = FLOW_DISSECT_RET_OUT_BAD;
1186 /* Process result of proto processing */
1188 case FLOW_DISSECT_RET_OUT_GOOD:
1190 case FLOW_DISSECT_RET_PROTO_AGAIN:
1191 if (skb_flow_dissect_allowed(&num_hdrs))
1194 case FLOW_DISSECT_RET_CONTINUE:
1195 case FLOW_DISSECT_RET_IPPROTO_AGAIN:
1197 case FLOW_DISSECT_RET_OUT_BAD:
1203 fdret = FLOW_DISSECT_RET_CONTINUE;
1207 fdret = __skb_flow_dissect_gre(skb, key_control, flow_dissector,
1208 target_container, data,
1209 &proto, &nhoff, &hlen, flags);
1213 case NEXTHDR_ROUTING:
1214 case NEXTHDR_DEST: {
1215 u8 _opthdr[2], *opthdr;
1217 if (proto != htons(ETH_P_IPV6))
1220 opthdr = __skb_header_pointer(skb, nhoff, sizeof(_opthdr),
1221 data, hlen, &_opthdr);
1223 fdret = FLOW_DISSECT_RET_OUT_BAD;
1227 ip_proto = opthdr[0];
1228 nhoff += (opthdr[1] + 1) << 3;
1230 fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
1233 case NEXTHDR_FRAGMENT: {
1234 struct frag_hdr _fh, *fh;
1236 if (proto != htons(ETH_P_IPV6))
1239 fh = __skb_header_pointer(skb, nhoff, sizeof(_fh),
1243 fdret = FLOW_DISSECT_RET_OUT_BAD;
1247 key_control->flags |= FLOW_DIS_IS_FRAGMENT;
1249 nhoff += sizeof(_fh);
1250 ip_proto = fh->nexthdr;
1252 if (!(fh->frag_off & htons(IP6_OFFSET))) {
1253 key_control->flags |= FLOW_DIS_FIRST_FRAG;
1254 if (flags & FLOW_DISSECTOR_F_PARSE_1ST_FRAG) {
1255 fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
1260 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1264 proto = htons(ETH_P_IP);
1266 key_control->flags |= FLOW_DIS_ENCAPSULATION;
1267 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
1268 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1272 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1276 proto = htons(ETH_P_IPV6);
1278 key_control->flags |= FLOW_DIS_ENCAPSULATION;
1279 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
1280 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1284 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1289 proto = htons(ETH_P_MPLS_UC);
1290 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1294 __skb_flow_dissect_tcp(skb, flow_dissector, target_container,
1302 if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS) &&
1303 !(key_control->flags & FLOW_DIS_IS_FRAGMENT)) {
1304 key_ports = skb_flow_dissector_target(flow_dissector,
1305 FLOW_DISSECTOR_KEY_PORTS,
1307 key_ports->ports = __skb_flow_get_ports(skb, nhoff, ip_proto,
1311 if (dissector_uses_key(flow_dissector,
1312 FLOW_DISSECTOR_KEY_ICMP)) {
1313 key_icmp = skb_flow_dissector_target(flow_dissector,
1314 FLOW_DISSECTOR_KEY_ICMP,
1316 key_icmp->icmp = skb_flow_get_be16(skb, nhoff, data, hlen);
1319 /* Process result of IP proto processing */
1321 case FLOW_DISSECT_RET_PROTO_AGAIN:
1322 if (skb_flow_dissect_allowed(&num_hdrs))
1325 case FLOW_DISSECT_RET_IPPROTO_AGAIN:
1326 if (skb_flow_dissect_allowed(&num_hdrs))
1327 goto ip_proto_again;
1329 case FLOW_DISSECT_RET_OUT_GOOD:
1330 case FLOW_DISSECT_RET_CONTINUE:
1332 case FLOW_DISSECT_RET_OUT_BAD:
1341 key_control->thoff = min_t(u16, nhoff, skb ? skb->len : hlen);
1342 key_basic->n_proto = proto;
1343 key_basic->ip_proto = ip_proto;
1351 EXPORT_SYMBOL(__skb_flow_dissect);
1353 static u32 hashrnd __read_mostly;
1354 static __always_inline void __flow_hash_secret_init(void)
1356 net_get_random_once(&hashrnd, sizeof(hashrnd));
1359 static __always_inline u32 __flow_hash_words(const u32 *words, u32 length,
1362 return jhash2(words, length, keyval);
1365 static inline const u32 *flow_keys_hash_start(const struct flow_keys *flow)
1367 const void *p = flow;
1369 BUILD_BUG_ON(FLOW_KEYS_HASH_OFFSET % sizeof(u32));
1370 return (const u32 *)(p + FLOW_KEYS_HASH_OFFSET);
1373 static inline size_t flow_keys_hash_length(const struct flow_keys *flow)
1375 size_t diff = FLOW_KEYS_HASH_OFFSET + sizeof(flow->addrs);
1376 BUILD_BUG_ON((sizeof(*flow) - FLOW_KEYS_HASH_OFFSET) % sizeof(u32));
1377 BUILD_BUG_ON(offsetof(typeof(*flow), addrs) !=
1378 sizeof(*flow) - sizeof(flow->addrs));
1380 switch (flow->control.addr_type) {
1381 case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1382 diff -= sizeof(flow->addrs.v4addrs);
1384 case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1385 diff -= sizeof(flow->addrs.v6addrs);
1387 case FLOW_DISSECTOR_KEY_TIPC:
1388 diff -= sizeof(flow->addrs.tipckey);
1391 return (sizeof(*flow) - diff) / sizeof(u32);
1394 __be32 flow_get_u32_src(const struct flow_keys *flow)
1396 switch (flow->control.addr_type) {
1397 case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1398 return flow->addrs.v4addrs.src;
1399 case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1400 return (__force __be32)ipv6_addr_hash(
1401 &flow->addrs.v6addrs.src);
1402 case FLOW_DISSECTOR_KEY_TIPC:
1403 return flow->addrs.tipckey.key;
1408 EXPORT_SYMBOL(flow_get_u32_src);
1410 __be32 flow_get_u32_dst(const struct flow_keys *flow)
1412 switch (flow->control.addr_type) {
1413 case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1414 return flow->addrs.v4addrs.dst;
1415 case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1416 return (__force __be32)ipv6_addr_hash(
1417 &flow->addrs.v6addrs.dst);
1422 EXPORT_SYMBOL(flow_get_u32_dst);
1424 static inline void __flow_hash_consistentify(struct flow_keys *keys)
1428 switch (keys->control.addr_type) {
1429 case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1430 addr_diff = (__force u32)keys->addrs.v4addrs.dst -
1431 (__force u32)keys->addrs.v4addrs.src;
1432 if ((addr_diff < 0) ||
1434 ((__force u16)keys->ports.dst <
1435 (__force u16)keys->ports.src))) {
1436 swap(keys->addrs.v4addrs.src, keys->addrs.v4addrs.dst);
1437 swap(keys->ports.src, keys->ports.dst);
1440 case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1441 addr_diff = memcmp(&keys->addrs.v6addrs.dst,
1442 &keys->addrs.v6addrs.src,
1443 sizeof(keys->addrs.v6addrs.dst));
1444 if ((addr_diff < 0) ||
1446 ((__force u16)keys->ports.dst <
1447 (__force u16)keys->ports.src))) {
1448 for (i = 0; i < 4; i++)
1449 swap(keys->addrs.v6addrs.src.s6_addr32[i],
1450 keys->addrs.v6addrs.dst.s6_addr32[i]);
1451 swap(keys->ports.src, keys->ports.dst);
1457 static inline u32 __flow_hash_from_keys(struct flow_keys *keys, u32 keyval)
1461 __flow_hash_consistentify(keys);
1463 hash = __flow_hash_words(flow_keys_hash_start(keys),
1464 flow_keys_hash_length(keys), keyval);
1471 u32 flow_hash_from_keys(struct flow_keys *keys)
1473 __flow_hash_secret_init();
1474 return __flow_hash_from_keys(keys, hashrnd);
1476 EXPORT_SYMBOL(flow_hash_from_keys);
1478 static inline u32 ___skb_get_hash(const struct sk_buff *skb,
1479 struct flow_keys *keys, u32 keyval)
1481 skb_flow_dissect_flow_keys(skb, keys,
1482 FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
1484 return __flow_hash_from_keys(keys, keyval);
1487 struct _flow_keys_digest_data {
1496 void make_flow_keys_digest(struct flow_keys_digest *digest,
1497 const struct flow_keys *flow)
1499 struct _flow_keys_digest_data *data =
1500 (struct _flow_keys_digest_data *)digest;
1502 BUILD_BUG_ON(sizeof(*data) > sizeof(*digest));
1504 memset(digest, 0, sizeof(*digest));
1506 data->n_proto = flow->basic.n_proto;
1507 data->ip_proto = flow->basic.ip_proto;
1508 data->ports = flow->ports.ports;
1509 data->src = flow->addrs.v4addrs.src;
1510 data->dst = flow->addrs.v4addrs.dst;
1512 EXPORT_SYMBOL(make_flow_keys_digest);
1514 static struct flow_dissector flow_keys_dissector_symmetric __read_mostly;
1516 u32 __skb_get_hash_symmetric(const struct sk_buff *skb)
1518 struct flow_keys keys;
1520 __flow_hash_secret_init();
1522 memset(&keys, 0, sizeof(keys));
1523 __skb_flow_dissect(NULL, skb, &flow_keys_dissector_symmetric,
1524 &keys, NULL, 0, 0, 0,
1525 FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
1527 return __flow_hash_from_keys(&keys, hashrnd);
1529 EXPORT_SYMBOL_GPL(__skb_get_hash_symmetric);
1532 * __skb_get_hash: calculate a flow hash
1533 * @skb: sk_buff to calculate flow hash from
1535 * This function calculates a flow hash based on src/dst addresses
1536 * and src/dst port numbers. Sets hash in skb to non-zero hash value
1537 * on success, zero indicates no valid hash. Also, sets l4_hash in skb
1538 * if hash is a canonical 4-tuple hash over transport ports.
1540 void __skb_get_hash(struct sk_buff *skb)
1542 struct flow_keys keys;
1545 __flow_hash_secret_init();
1547 hash = ___skb_get_hash(skb, &keys, hashrnd);
1549 __skb_set_sw_hash(skb, hash, flow_keys_have_l4(&keys));
1551 EXPORT_SYMBOL(__skb_get_hash);
1553 __u32 skb_get_hash_perturb(const struct sk_buff *skb, u32 perturb)
1555 struct flow_keys keys;
1557 return ___skb_get_hash(skb, &keys, perturb);
1559 EXPORT_SYMBOL(skb_get_hash_perturb);
1561 u32 __skb_get_poff(const struct sk_buff *skb, void *data,
1562 const struct flow_keys_basic *keys, int hlen)
1564 u32 poff = keys->control.thoff;
1566 /* skip L4 headers for fragments after the first */
1567 if ((keys->control.flags & FLOW_DIS_IS_FRAGMENT) &&
1568 !(keys->control.flags & FLOW_DIS_FIRST_FRAG))
1571 switch (keys->basic.ip_proto) {
1573 /* access doff as u8 to avoid unaligned access */
1577 doff = __skb_header_pointer(skb, poff + 12, sizeof(_doff),
1578 data, hlen, &_doff);
1582 poff += max_t(u32, sizeof(struct tcphdr), (*doff & 0xF0) >> 2);
1586 case IPPROTO_UDPLITE:
1587 poff += sizeof(struct udphdr);
1589 /* For the rest, we do not really care about header
1590 * extensions at this point for now.
1593 poff += sizeof(struct icmphdr);
1595 case IPPROTO_ICMPV6:
1596 poff += sizeof(struct icmp6hdr);
1599 poff += sizeof(struct igmphdr);
1602 poff += sizeof(struct dccp_hdr);
1605 poff += sizeof(struct sctphdr);
1613 * skb_get_poff - get the offset to the payload
1614 * @skb: sk_buff to get the payload offset from
1616 * The function will get the offset to the payload as far as it could
1617 * be dissected. The main user is currently BPF, so that we can dynamically
1618 * truncate packets without needing to push actual payload to the user
1619 * space and can analyze headers only, instead.
1621 u32 skb_get_poff(const struct sk_buff *skb)
1623 struct flow_keys_basic keys;
1625 if (!skb_flow_dissect_flow_keys_basic(NULL, skb, &keys,
1629 return __skb_get_poff(skb, skb->data, &keys, skb_headlen(skb));
1632 __u32 __get_hash_from_flowi6(const struct flowi6 *fl6, struct flow_keys *keys)
1634 memset(keys, 0, sizeof(*keys));
1636 memcpy(&keys->addrs.v6addrs.src, &fl6->saddr,
1637 sizeof(keys->addrs.v6addrs.src));
1638 memcpy(&keys->addrs.v6addrs.dst, &fl6->daddr,
1639 sizeof(keys->addrs.v6addrs.dst));
1640 keys->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
1641 keys->ports.src = fl6->fl6_sport;
1642 keys->ports.dst = fl6->fl6_dport;
1643 keys->keyid.keyid = fl6->fl6_gre_key;
1644 keys->tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);
1645 keys->basic.ip_proto = fl6->flowi6_proto;
1647 return flow_hash_from_keys(keys);
1649 EXPORT_SYMBOL(__get_hash_from_flowi6);
1651 static const struct flow_dissector_key flow_keys_dissector_keys[] = {
1653 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
1654 .offset = offsetof(struct flow_keys, control),
1657 .key_id = FLOW_DISSECTOR_KEY_BASIC,
1658 .offset = offsetof(struct flow_keys, basic),
1661 .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
1662 .offset = offsetof(struct flow_keys, addrs.v4addrs),
1665 .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
1666 .offset = offsetof(struct flow_keys, addrs.v6addrs),
1669 .key_id = FLOW_DISSECTOR_KEY_TIPC,
1670 .offset = offsetof(struct flow_keys, addrs.tipckey),
1673 .key_id = FLOW_DISSECTOR_KEY_PORTS,
1674 .offset = offsetof(struct flow_keys, ports),
1677 .key_id = FLOW_DISSECTOR_KEY_VLAN,
1678 .offset = offsetof(struct flow_keys, vlan),
1681 .key_id = FLOW_DISSECTOR_KEY_FLOW_LABEL,
1682 .offset = offsetof(struct flow_keys, tags),
1685 .key_id = FLOW_DISSECTOR_KEY_GRE_KEYID,
1686 .offset = offsetof(struct flow_keys, keyid),
1690 static const struct flow_dissector_key flow_keys_dissector_symmetric_keys[] = {
1692 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
1693 .offset = offsetof(struct flow_keys, control),
1696 .key_id = FLOW_DISSECTOR_KEY_BASIC,
1697 .offset = offsetof(struct flow_keys, basic),
1700 .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
1701 .offset = offsetof(struct flow_keys, addrs.v4addrs),
1704 .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
1705 .offset = offsetof(struct flow_keys, addrs.v6addrs),
1708 .key_id = FLOW_DISSECTOR_KEY_PORTS,
1709 .offset = offsetof(struct flow_keys, ports),
1713 static const struct flow_dissector_key flow_keys_basic_dissector_keys[] = {
1715 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
1716 .offset = offsetof(struct flow_keys, control),
1719 .key_id = FLOW_DISSECTOR_KEY_BASIC,
1720 .offset = offsetof(struct flow_keys, basic),
1724 struct flow_dissector flow_keys_dissector __read_mostly;
1725 EXPORT_SYMBOL(flow_keys_dissector);
1727 struct flow_dissector flow_keys_basic_dissector __read_mostly;
1728 EXPORT_SYMBOL(flow_keys_basic_dissector);
1730 static int __init init_default_flow_dissectors(void)
1732 skb_flow_dissector_init(&flow_keys_dissector,
1733 flow_keys_dissector_keys,
1734 ARRAY_SIZE(flow_keys_dissector_keys));
1735 skb_flow_dissector_init(&flow_keys_dissector_symmetric,
1736 flow_keys_dissector_symmetric_keys,
1737 ARRAY_SIZE(flow_keys_dissector_symmetric_keys));
1738 skb_flow_dissector_init(&flow_keys_basic_dissector,
1739 flow_keys_basic_dissector_keys,
1740 ARRAY_SIZE(flow_keys_basic_dissector_keys));
1744 core_initcall(init_default_flow_dissectors);