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
40 static 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
46 void 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 }
74 EXPORT_SYMBOL(skb_flow_dissector_init);
75
76 #ifdef CONFIG_BPF_SYSCALL
77 int 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 }
140 EXPORT_SYMBOL(__skb_flow_get_ports);
141
142 static 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 */
165 void 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 }
186 EXPORT_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 */
191 static 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
208 static 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
230 static 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
252 static 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
276 void 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 }
299 EXPORT_SYMBOL(skb_flow_dissect_meta);
300
301 static void
302 skb_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
319 void
320 skb_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 }
363 EXPORT_SYMBOL(skb_flow_dissect_ct);
364
365 void
366 skb_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 }
495 EXPORT_SYMBOL(skb_flow_dissect_tunnel_info);
496
497 void 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 }
512 EXPORT_SYMBOL(skb_flow_dissect_hash);
513
514 static 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
572 static 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
628 static 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
652 static 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 */
793 static 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
825 static 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
850 static 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 enum flow_dissector_key_id dissector_ports = FLOW_DISSECTOR_KEY_MAX;
857 struct flow_dissector_key_ports *key_ports;
858
859 if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS))
860 dissector_ports = FLOW_DISSECTOR_KEY_PORTS;
861 else if (dissector_uses_key(flow_dissector,
862 FLOW_DISSECTOR_KEY_PORTS_RANGE))
863 dissector_ports = FLOW_DISSECTOR_KEY_PORTS_RANGE;
864
865 if (dissector_ports == FLOW_DISSECTOR_KEY_MAX)
866 return;
867
868 key_ports = skb_flow_dissector_target(flow_dissector,
869 dissector_ports,
870 target_container);
871 key_ports->ports = __skb_flow_get_ports(skb, nhoff, ip_proto,
872 data, hlen);
873 }
874
875 static void
876 __skb_flow_dissect_ipv4(const struct sk_buff *skb,
877 struct flow_dissector *flow_dissector,
878 void *target_container, const void *data,
879 const struct iphdr *iph)
880 {
881 struct flow_dissector_key_ip *key_ip;
882
883 if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
884 return;
885
886 key_ip = skb_flow_dissector_target(flow_dissector,
887 FLOW_DISSECTOR_KEY_IP,
888 target_container);
889 key_ip->tos = iph->tos;
890 key_ip->ttl = iph->ttl;
891 }
892
893 static void
894 __skb_flow_dissect_ipv6(const struct sk_buff *skb,
895 struct flow_dissector *flow_dissector,
896 void *target_container, const void *data,
897 const struct ipv6hdr *iph)
898 {
899 struct flow_dissector_key_ip *key_ip;
900
901 if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
902 return;
903
904 key_ip = skb_flow_dissector_target(flow_dissector,
905 FLOW_DISSECTOR_KEY_IP,
906 target_container);
907 key_ip->tos = ipv6_get_dsfield(iph);
908 key_ip->ttl = iph->hop_limit;
909 }
910
911 /* Maximum number of protocol headers that can be parsed in
912 * __skb_flow_dissect
913 */
914 #define MAX_FLOW_DISSECT_HDRS 15
915
916 static bool skb_flow_dissect_allowed(int *num_hdrs)
917 {
918 ++*num_hdrs;
919
920 return (*num_hdrs <= MAX_FLOW_DISSECT_HDRS);
921 }
922
923 static void __skb_flow_bpf_to_target(const struct bpf_flow_keys *flow_keys,
924 struct flow_dissector *flow_dissector,
925 void *target_container)
926 {
927 struct flow_dissector_key_ports *key_ports = NULL;
928 struct flow_dissector_key_control *key_control;
929 struct flow_dissector_key_basic *key_basic;
930 struct flow_dissector_key_addrs *key_addrs;
931 struct flow_dissector_key_tags *key_tags;
932
933 key_control = skb_flow_dissector_target(flow_dissector,
934 FLOW_DISSECTOR_KEY_CONTROL,
935 target_container);
936 key_control->thoff = flow_keys->thoff;
937 if (flow_keys->is_frag)
938 key_control->flags |= FLOW_DIS_IS_FRAGMENT;
939 if (flow_keys->is_first_frag)
940 key_control->flags |= FLOW_DIS_FIRST_FRAG;
941 if (flow_keys->is_encap)
942 key_control->flags |= FLOW_DIS_ENCAPSULATION;
943
944 key_basic = skb_flow_dissector_target(flow_dissector,
945 FLOW_DISSECTOR_KEY_BASIC,
946 target_container);
947 key_basic->n_proto = flow_keys->n_proto;
948 key_basic->ip_proto = flow_keys->ip_proto;
949
950 if (flow_keys->addr_proto == ETH_P_IP &&
951 dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
952 key_addrs = skb_flow_dissector_target(flow_dissector,
953 FLOW_DISSECTOR_KEY_IPV4_ADDRS,
954 target_container);
955 key_addrs->v4addrs.src = flow_keys->ipv4_src;
956 key_addrs->v4addrs.dst = flow_keys->ipv4_dst;
957 key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
958 } else if (flow_keys->addr_proto == ETH_P_IPV6 &&
959 dissector_uses_key(flow_dissector,
960 FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
961 key_addrs = skb_flow_dissector_target(flow_dissector,
962 FLOW_DISSECTOR_KEY_IPV6_ADDRS,
963 target_container);
964 memcpy(&key_addrs->v6addrs.src, &flow_keys->ipv6_src,
965 sizeof(key_addrs->v6addrs.src));
966 memcpy(&key_addrs->v6addrs.dst, &flow_keys->ipv6_dst,
967 sizeof(key_addrs->v6addrs.dst));
968 key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
969 }
970
971 if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS))
972 key_ports = skb_flow_dissector_target(flow_dissector,
973 FLOW_DISSECTOR_KEY_PORTS,
974 target_container);
975 else if (dissector_uses_key(flow_dissector,
976 FLOW_DISSECTOR_KEY_PORTS_RANGE))
977 key_ports = skb_flow_dissector_target(flow_dissector,
978 FLOW_DISSECTOR_KEY_PORTS_RANGE,
979 target_container);
980
981 if (key_ports) {
982 key_ports->src = flow_keys->sport;
983 key_ports->dst = flow_keys->dport;
984 }
985
986 if (dissector_uses_key(flow_dissector,
987 FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
988 key_tags = skb_flow_dissector_target(flow_dissector,
989 FLOW_DISSECTOR_KEY_FLOW_LABEL,
990 target_container);
991 key_tags->flow_label = ntohl(flow_keys->flow_label);
992 }
993 }
994
995 u32 bpf_flow_dissect(struct bpf_prog *prog, struct bpf_flow_dissector *ctx,
996 __be16 proto, int nhoff, int hlen, unsigned int flags)
997 {
998 struct bpf_flow_keys *flow_keys = ctx->flow_keys;
999 u32 result;
1000
1001 /* Pass parameters to the BPF program */
1002 memset(flow_keys, 0, sizeof(*flow_keys));
1003 flow_keys->n_proto = proto;
1004 flow_keys->nhoff = nhoff;
1005 flow_keys->thoff = flow_keys->nhoff;
1006
1007 BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_PARSE_1ST_FRAG !=
1008 (int)FLOW_DISSECTOR_F_PARSE_1ST_FRAG);
1009 BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL !=
1010 (int)FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
1011 BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_STOP_AT_ENCAP !=
1012 (int)FLOW_DISSECTOR_F_STOP_AT_ENCAP);
1013 flow_keys->flags = flags;
1014
1015 result = bpf_prog_run_pin_on_cpu(prog, ctx);
1016
1017 flow_keys->nhoff = clamp_t(u16, flow_keys->nhoff, nhoff, hlen);
1018 flow_keys->thoff = clamp_t(u16, flow_keys->thoff,
1019 flow_keys->nhoff, hlen);
1020
1021 return result;
1022 }
1023
1024 static bool is_pppoe_ses_hdr_valid(const struct pppoe_hdr *hdr)
1025 {
1026 return hdr->ver == 1 && hdr->type == 1 && hdr->code == 0;
1027 }
1028
1029 /**
1030 * __skb_flow_dissect - extract the flow_keys struct and return it
1031 * @net: associated network namespace, derived from @skb if NULL
1032 * @skb: sk_buff to extract the flow from, can be NULL if the rest are specified
1033 * @flow_dissector: list of keys to dissect
1034 * @target_container: target structure to put dissected values into
1035 * @data: raw buffer pointer to the packet, if NULL use skb->data
1036 * @proto: protocol for which to get the flow, if @data is NULL use skb->protocol
1037 * @nhoff: network header offset, if @data is NULL use skb_network_offset(skb)
1038 * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
1039 * @flags: flags that control the dissection process, e.g.
1040 * FLOW_DISSECTOR_F_STOP_AT_ENCAP.
1041 *
1042 * The function will try to retrieve individual keys into target specified
1043 * by flow_dissector from either the skbuff or a raw buffer specified by the
1044 * rest parameters.
1045 *
1046 * Caller must take care of zeroing target container memory.
1047 */
1048 bool __skb_flow_dissect(const struct net *net,
1049 const struct sk_buff *skb,
1050 struct flow_dissector *flow_dissector,
1051 void *target_container, const void *data,
1052 __be16 proto, int nhoff, int hlen, unsigned int flags)
1053 {
1054 struct flow_dissector_key_control *key_control;
1055 struct flow_dissector_key_basic *key_basic;
1056 struct flow_dissector_key_addrs *key_addrs;
1057 struct flow_dissector_key_tags *key_tags;
1058 struct flow_dissector_key_vlan *key_vlan;
1059 enum flow_dissect_ret fdret;
1060 enum flow_dissector_key_id dissector_vlan = FLOW_DISSECTOR_KEY_MAX;
1061 bool mpls_el = false;
1062 int mpls_lse = 0;
1063 int num_hdrs = 0;
1064 u8 ip_proto = 0;
1065 bool ret;
1066
1067 if (!data) {
1068 data = skb->data;
1069 proto = skb_vlan_tag_present(skb) ?
1070 skb->vlan_proto : skb->protocol;
1071 nhoff = skb_network_offset(skb);
1072 hlen = skb_headlen(skb);
1073 #if IS_ENABLED(CONFIG_NET_DSA)
1074 if (unlikely(skb->dev && netdev_uses_dsa(skb->dev) &&
1075 proto == htons(ETH_P_XDSA))) {
1076 struct metadata_dst *md_dst = skb_metadata_dst(skb);
1077 const struct dsa_device_ops *ops;
1078 int offset = 0;
1079
1080 ops = skb->dev->dsa_ptr->tag_ops;
1081 /* Only DSA header taggers break flow dissection */
1082 if (ops->needed_headroom &&
1083 (!md_dst || md_dst->type != METADATA_HW_PORT_MUX)) {
1084 if (ops->flow_dissect)
1085 ops->flow_dissect(skb, &proto, &offset);
1086 else
1087 dsa_tag_generic_flow_dissect(skb,
1088 &proto,
1089 &offset);
1090 hlen -= offset;
1091 nhoff += offset;
1092 }
1093 }
1094 #endif
1095 }
1096
1097 /* It is ensured by skb_flow_dissector_init() that control key will
1098 * be always present.
1099 */
1100 key_control = skb_flow_dissector_target(flow_dissector,
1101 FLOW_DISSECTOR_KEY_CONTROL,
1102 target_container);
1103
1104 /* It is ensured by skb_flow_dissector_init() that basic key will
1105 * be always present.
1106 */
1107 key_basic = skb_flow_dissector_target(flow_dissector,
1108 FLOW_DISSECTOR_KEY_BASIC,
1109 target_container);
1110
1111 if (skb) {
1112 if (!net) {
1113 if (skb->dev)
1114 net = dev_net(skb->dev);
1115 else if (skb->sk)
1116 net = sock_net(skb->sk);
1117 }
1118 }
1119
1120 DEBUG_NET_WARN_ON_ONCE(!net);
1121 if (net) {
1122 enum netns_bpf_attach_type type = NETNS_BPF_FLOW_DISSECTOR;
1123 struct bpf_prog_array *run_array;
1124
1125 rcu_read_lock();
1126 run_array = rcu_dereference(init_net.bpf.run_array[type]);
1127 if (!run_array)
1128 run_array = rcu_dereference(net->bpf.run_array[type]);
1129
1130 if (run_array) {
1131 struct bpf_flow_keys flow_keys;
1132 struct bpf_flow_dissector ctx = {
1133 .flow_keys = &flow_keys,
1134 .data = data,
1135 .data_end = data + hlen,
1136 };
1137 __be16 n_proto = proto;
1138 struct bpf_prog *prog;
1139 u32 result;
1140
1141 if (skb) {
1142 ctx.skb = skb;
1143 /* we can't use 'proto' in the skb case
1144 * because it might be set to skb->vlan_proto
1145 * which has been pulled from the data
1146 */
1147 n_proto = skb->protocol;
1148 }
1149
1150 prog = READ_ONCE(run_array->items[0].prog);
1151 result = bpf_flow_dissect(prog, &ctx, n_proto, nhoff,
1152 hlen, flags);
1153 if (result == BPF_FLOW_DISSECTOR_CONTINUE)
1154 goto dissect_continue;
1155 __skb_flow_bpf_to_target(&flow_keys, flow_dissector,
1156 target_container);
1157 rcu_read_unlock();
1158 return result == BPF_OK;
1159 }
1160 dissect_continue:
1161 rcu_read_unlock();
1162 }
1163
1164 if (dissector_uses_key(flow_dissector,
1165 FLOW_DISSECTOR_KEY_ETH_ADDRS)) {
1166 struct ethhdr *eth = eth_hdr(skb);
1167 struct flow_dissector_key_eth_addrs *key_eth_addrs;
1168
1169 key_eth_addrs = skb_flow_dissector_target(flow_dissector,
1170 FLOW_DISSECTOR_KEY_ETH_ADDRS,
1171 target_container);
1172 memcpy(key_eth_addrs, eth, sizeof(*key_eth_addrs));
1173 }
1174
1175 if (dissector_uses_key(flow_dissector,
1176 FLOW_DISSECTOR_KEY_NUM_OF_VLANS)) {
1177 struct flow_dissector_key_num_of_vlans *key_num_of_vlans;
1178
1179 key_num_of_vlans = skb_flow_dissector_target(flow_dissector,
1180 FLOW_DISSECTOR_KEY_NUM_OF_VLANS,
1181 target_container);
1182 key_num_of_vlans->num_of_vlans = 0;
1183 }
1184
1185 proto_again:
1186 fdret = FLOW_DISSECT_RET_CONTINUE;
1187
1188 switch (proto) {
1189 case htons(ETH_P_IP): {
1190 const struct iphdr *iph;
1191 struct iphdr _iph;
1192
1193 iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
1194 if (!iph || iph->ihl < 5) {
1195 fdret = FLOW_DISSECT_RET_OUT_BAD;
1196 break;
1197 }
1198
1199 nhoff += iph->ihl * 4;
1200
1201 ip_proto = iph->protocol;
1202
1203 if (dissector_uses_key(flow_dissector,
1204 FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
1205 key_addrs = skb_flow_dissector_target(flow_dissector,
1206 FLOW_DISSECTOR_KEY_IPV4_ADDRS,
1207 target_container);
1208
1209 memcpy(&key_addrs->v4addrs.src, &iph->saddr,
1210 sizeof(key_addrs->v4addrs.src));
1211 memcpy(&key_addrs->v4addrs.dst, &iph->daddr,
1212 sizeof(key_addrs->v4addrs.dst));
1213 key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
1214 }
1215
1216 __skb_flow_dissect_ipv4(skb, flow_dissector,
1217 target_container, data, iph);
1218
1219 if (ip_is_fragment(iph)) {
1220 key_control->flags |= FLOW_DIS_IS_FRAGMENT;
1221
1222 if (iph->frag_off & htons(IP_OFFSET)) {
1223 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1224 break;
1225 } else {
1226 key_control->flags |= FLOW_DIS_FIRST_FRAG;
1227 if (!(flags &
1228 FLOW_DISSECTOR_F_PARSE_1ST_FRAG)) {
1229 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1230 break;
1231 }
1232 }
1233 }
1234
1235 break;
1236 }
1237 case htons(ETH_P_IPV6): {
1238 const struct ipv6hdr *iph;
1239 struct ipv6hdr _iph;
1240
1241 iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
1242 if (!iph) {
1243 fdret = FLOW_DISSECT_RET_OUT_BAD;
1244 break;
1245 }
1246
1247 ip_proto = iph->nexthdr;
1248 nhoff += sizeof(struct ipv6hdr);
1249
1250 if (dissector_uses_key(flow_dissector,
1251 FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
1252 key_addrs = skb_flow_dissector_target(flow_dissector,
1253 FLOW_DISSECTOR_KEY_IPV6_ADDRS,
1254 target_container);
1255
1256 memcpy(&key_addrs->v6addrs.src, &iph->saddr,
1257 sizeof(key_addrs->v6addrs.src));
1258 memcpy(&key_addrs->v6addrs.dst, &iph->daddr,
1259 sizeof(key_addrs->v6addrs.dst));
1260 key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
1261 }
1262
1263 if ((dissector_uses_key(flow_dissector,
1264 FLOW_DISSECTOR_KEY_FLOW_LABEL) ||
1265 (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL)) &&
1266 ip6_flowlabel(iph)) {
1267 __be32 flow_label = ip6_flowlabel(iph);
1268
1269 if (dissector_uses_key(flow_dissector,
1270 FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
1271 key_tags = skb_flow_dissector_target(flow_dissector,
1272 FLOW_DISSECTOR_KEY_FLOW_LABEL,
1273 target_container);
1274 key_tags->flow_label = ntohl(flow_label);
1275 }
1276 if (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL) {
1277 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1278 break;
1279 }
1280 }
1281
1282 __skb_flow_dissect_ipv6(skb, flow_dissector,
1283 target_container, data, iph);
1284
1285 break;
1286 }
1287 case htons(ETH_P_8021AD):
1288 case htons(ETH_P_8021Q): {
1289 const struct vlan_hdr *vlan = NULL;
1290 struct vlan_hdr _vlan;
1291 __be16 saved_vlan_tpid = proto;
1292
1293 if (dissector_vlan == FLOW_DISSECTOR_KEY_MAX &&
1294 skb && skb_vlan_tag_present(skb)) {
1295 proto = skb->protocol;
1296 } else {
1297 vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan),
1298 data, hlen, &_vlan);
1299 if (!vlan) {
1300 fdret = FLOW_DISSECT_RET_OUT_BAD;
1301 break;
1302 }
1303
1304 proto = vlan->h_vlan_encapsulated_proto;
1305 nhoff += sizeof(*vlan);
1306 }
1307
1308 if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_NUM_OF_VLANS) &&
1309 !(key_control->flags & FLOW_DIS_ENCAPSULATION)) {
1310 struct flow_dissector_key_num_of_vlans *key_nvs;
1311
1312 key_nvs = skb_flow_dissector_target(flow_dissector,
1313 FLOW_DISSECTOR_KEY_NUM_OF_VLANS,
1314 target_container);
1315 key_nvs->num_of_vlans++;
1316 }
1317
1318 if (dissector_vlan == FLOW_DISSECTOR_KEY_MAX) {
1319 dissector_vlan = FLOW_DISSECTOR_KEY_VLAN;
1320 } else if (dissector_vlan == FLOW_DISSECTOR_KEY_VLAN) {
1321 dissector_vlan = FLOW_DISSECTOR_KEY_CVLAN;
1322 } else {
1323 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1324 break;
1325 }
1326
1327 if (dissector_uses_key(flow_dissector, dissector_vlan)) {
1328 key_vlan = skb_flow_dissector_target(flow_dissector,
1329 dissector_vlan,
1330 target_container);
1331
1332 if (!vlan) {
1333 key_vlan->vlan_id = skb_vlan_tag_get_id(skb);
1334 key_vlan->vlan_priority = skb_vlan_tag_get_prio(skb);
1335 } else {
1336 key_vlan->vlan_id = ntohs(vlan->h_vlan_TCI) &
1337 VLAN_VID_MASK;
1338 key_vlan->vlan_priority =
1339 (ntohs(vlan->h_vlan_TCI) &
1340 VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
1341 }
1342 key_vlan->vlan_tpid = saved_vlan_tpid;
1343 key_vlan->vlan_eth_type = proto;
1344 }
1345
1346 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1347 break;
1348 }
1349 case htons(ETH_P_PPP_SES): {
1350 struct {
1351 struct pppoe_hdr hdr;
1352 __be16 proto;
1353 } *hdr, _hdr;
1354 u16 ppp_proto;
1355
1356 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
1357 if (!hdr) {
1358 fdret = FLOW_DISSECT_RET_OUT_BAD;
1359 break;
1360 }
1361
1362 if (!is_pppoe_ses_hdr_valid(&hdr->hdr)) {
1363 fdret = FLOW_DISSECT_RET_OUT_BAD;
1364 break;
1365 }
1366
1367 /* least significant bit of the most significant octet
1368 * indicates if protocol field was compressed
1369 */
1370 ppp_proto = ntohs(hdr->proto);
1371 if (ppp_proto & 0x0100) {
1372 ppp_proto = ppp_proto >> 8;
1373 nhoff += PPPOE_SES_HLEN - 1;
1374 } else {
1375 nhoff += PPPOE_SES_HLEN;
1376 }
1377
1378 if (ppp_proto == PPP_IP) {
1379 proto = htons(ETH_P_IP);
1380 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1381 } else if (ppp_proto == PPP_IPV6) {
1382 proto = htons(ETH_P_IPV6);
1383 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1384 } else if (ppp_proto == PPP_MPLS_UC) {
1385 proto = htons(ETH_P_MPLS_UC);
1386 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1387 } else if (ppp_proto == PPP_MPLS_MC) {
1388 proto = htons(ETH_P_MPLS_MC);
1389 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1390 } else if (ppp_proto_is_valid(ppp_proto)) {
1391 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1392 } else {
1393 fdret = FLOW_DISSECT_RET_OUT_BAD;
1394 break;
1395 }
1396
1397 if (dissector_uses_key(flow_dissector,
1398 FLOW_DISSECTOR_KEY_PPPOE)) {
1399 struct flow_dissector_key_pppoe *key_pppoe;
1400
1401 key_pppoe = skb_flow_dissector_target(flow_dissector,
1402 FLOW_DISSECTOR_KEY_PPPOE,
1403 target_container);
1404 key_pppoe->session_id = hdr->hdr.sid;
1405 key_pppoe->ppp_proto = htons(ppp_proto);
1406 key_pppoe->type = htons(ETH_P_PPP_SES);
1407 }
1408 break;
1409 }
1410 case htons(ETH_P_TIPC): {
1411 struct tipc_basic_hdr *hdr, _hdr;
1412
1413 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr),
1414 data, hlen, &_hdr);
1415 if (!hdr) {
1416 fdret = FLOW_DISSECT_RET_OUT_BAD;
1417 break;
1418 }
1419
1420 if (dissector_uses_key(flow_dissector,
1421 FLOW_DISSECTOR_KEY_TIPC)) {
1422 key_addrs = skb_flow_dissector_target(flow_dissector,
1423 FLOW_DISSECTOR_KEY_TIPC,
1424 target_container);
1425 key_addrs->tipckey.key = tipc_hdr_rps_key(hdr);
1426 key_control->addr_type = FLOW_DISSECTOR_KEY_TIPC;
1427 }
1428 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1429 break;
1430 }
1431
1432 case htons(ETH_P_MPLS_UC):
1433 case htons(ETH_P_MPLS_MC):
1434 fdret = __skb_flow_dissect_mpls(skb, flow_dissector,
1435 target_container, data,
1436 nhoff, hlen, mpls_lse,
1437 &mpls_el);
1438 nhoff += sizeof(struct mpls_label);
1439 mpls_lse++;
1440 break;
1441 case htons(ETH_P_FCOE):
1442 if ((hlen - nhoff) < FCOE_HEADER_LEN) {
1443 fdret = FLOW_DISSECT_RET_OUT_BAD;
1444 break;
1445 }
1446
1447 nhoff += FCOE_HEADER_LEN;
1448 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1449 break;
1450
1451 case htons(ETH_P_ARP):
1452 case htons(ETH_P_RARP):
1453 fdret = __skb_flow_dissect_arp(skb, flow_dissector,
1454 target_container, data,
1455 nhoff, hlen);
1456 break;
1457
1458 case htons(ETH_P_BATMAN):
1459 fdret = __skb_flow_dissect_batadv(skb, key_control, data,
1460 &proto, &nhoff, hlen, flags);
1461 break;
1462
1463 case htons(ETH_P_1588): {
1464 struct ptp_header *hdr, _hdr;
1465
1466 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
1467 hlen, &_hdr);
1468 if (!hdr) {
1469 fdret = FLOW_DISSECT_RET_OUT_BAD;
1470 break;
1471 }
1472
1473 nhoff += sizeof(struct ptp_header);
1474 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1475 break;
1476 }
1477
1478 case htons(ETH_P_PRP):
1479 case htons(ETH_P_HSR): {
1480 struct hsr_tag *hdr, _hdr;
1481
1482 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen,
1483 &_hdr);
1484 if (!hdr) {
1485 fdret = FLOW_DISSECT_RET_OUT_BAD;
1486 break;
1487 }
1488
1489 proto = hdr->encap_proto;
1490 nhoff += HSR_HLEN;
1491 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1492 break;
1493 }
1494
1495 case htons(ETH_P_CFM):
1496 fdret = __skb_flow_dissect_cfm(skb, flow_dissector,
1497 target_container, data,
1498 nhoff, hlen);
1499 break;
1500
1501 default:
1502 fdret = FLOW_DISSECT_RET_OUT_BAD;
1503 break;
1504 }
1505
1506 /* Process result of proto processing */
1507 switch (fdret) {
1508 case FLOW_DISSECT_RET_OUT_GOOD:
1509 goto out_good;
1510 case FLOW_DISSECT_RET_PROTO_AGAIN:
1511 if (skb_flow_dissect_allowed(&num_hdrs))
1512 goto proto_again;
1513 goto out_good;
1514 case FLOW_DISSECT_RET_CONTINUE:
1515 case FLOW_DISSECT_RET_IPPROTO_AGAIN:
1516 break;
1517 case FLOW_DISSECT_RET_OUT_BAD:
1518 default:
1519 goto out_bad;
1520 }
1521
1522 ip_proto_again:
1523 fdret = FLOW_DISSECT_RET_CONTINUE;
1524
1525 switch (ip_proto) {
1526 case IPPROTO_GRE:
1527 if (flags & FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP) {
1528 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1529 break;
1530 }
1531
1532 fdret = __skb_flow_dissect_gre(skb, key_control, flow_dissector,
1533 target_container, data,
1534 &proto, &nhoff, &hlen, flags);
1535 break;
1536
1537 case NEXTHDR_HOP:
1538 case NEXTHDR_ROUTING:
1539 case NEXTHDR_DEST: {
1540 u8 _opthdr[2], *opthdr;
1541
1542 if (proto != htons(ETH_P_IPV6))
1543 break;
1544
1545 opthdr = __skb_header_pointer(skb, nhoff, sizeof(_opthdr),
1546 data, hlen, &_opthdr);
1547 if (!opthdr) {
1548 fdret = FLOW_DISSECT_RET_OUT_BAD;
1549 break;
1550 }
1551
1552 ip_proto = opthdr[0];
1553 nhoff += (opthdr[1] + 1) << 3;
1554
1555 fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
1556 break;
1557 }
1558 case NEXTHDR_FRAGMENT: {
1559 struct frag_hdr _fh, *fh;
1560
1561 if (proto != htons(ETH_P_IPV6))
1562 break;
1563
1564 fh = __skb_header_pointer(skb, nhoff, sizeof(_fh),
1565 data, hlen, &_fh);
1566
1567 if (!fh) {
1568 fdret = FLOW_DISSECT_RET_OUT_BAD;
1569 break;
1570 }
1571
1572 key_control->flags |= FLOW_DIS_IS_FRAGMENT;
1573
1574 nhoff += sizeof(_fh);
1575 ip_proto = fh->nexthdr;
1576
1577 if (!(fh->frag_off & htons(IP6_OFFSET))) {
1578 key_control->flags |= FLOW_DIS_FIRST_FRAG;
1579 if (flags & FLOW_DISSECTOR_F_PARSE_1ST_FRAG) {
1580 fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
1581 break;
1582 }
1583 }
1584
1585 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1586 break;
1587 }
1588 case IPPROTO_IPIP:
1589 if (flags & FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP) {
1590 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1591 break;
1592 }
1593
1594 proto = htons(ETH_P_IP);
1595
1596 key_control->flags |= FLOW_DIS_ENCAPSULATION;
1597 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
1598 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1599 break;
1600 }
1601
1602 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1603 break;
1604
1605 case IPPROTO_IPV6:
1606 if (flags & FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP) {
1607 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1608 break;
1609 }
1610
1611 proto = htons(ETH_P_IPV6);
1612
1613 key_control->flags |= FLOW_DIS_ENCAPSULATION;
1614 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
1615 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1616 break;
1617 }
1618
1619 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1620 break;
1621
1622
1623 case IPPROTO_MPLS:
1624 proto = htons(ETH_P_MPLS_UC);
1625 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1626 break;
1627
1628 case IPPROTO_TCP:
1629 __skb_flow_dissect_tcp(skb, flow_dissector, target_container,
1630 data, nhoff, hlen);
1631 break;
1632
1633 case IPPROTO_ICMP:
1634 case IPPROTO_ICMPV6:
1635 __skb_flow_dissect_icmp(skb, flow_dissector, target_container,
1636 data, nhoff, hlen);
1637 break;
1638 case IPPROTO_L2TP:
1639 __skb_flow_dissect_l2tpv3(skb, flow_dissector, target_container,
1640 data, nhoff, hlen);
1641 break;
1642 case IPPROTO_ESP:
1643 __skb_flow_dissect_esp(skb, flow_dissector, target_container,
1644 data, nhoff, hlen);
1645 break;
1646 case IPPROTO_AH:
1647 __skb_flow_dissect_ah(skb, flow_dissector, target_container,
1648 data, nhoff, hlen);
1649 break;
1650 default:
1651 break;
1652 }
1653
1654 if (!(key_control->flags & FLOW_DIS_IS_FRAGMENT))
1655 __skb_flow_dissect_ports(skb, flow_dissector, target_container,
1656 data, nhoff, ip_proto, hlen);
1657
1658 /* Process result of IP proto processing */
1659 switch (fdret) {
1660 case FLOW_DISSECT_RET_PROTO_AGAIN:
1661 if (skb_flow_dissect_allowed(&num_hdrs))
1662 goto proto_again;
1663 break;
1664 case FLOW_DISSECT_RET_IPPROTO_AGAIN:
1665 if (skb_flow_dissect_allowed(&num_hdrs))
1666 goto ip_proto_again;
1667 break;
1668 case FLOW_DISSECT_RET_OUT_GOOD:
1669 case FLOW_DISSECT_RET_CONTINUE:
1670 break;
1671 case FLOW_DISSECT_RET_OUT_BAD:
1672 default:
1673 goto out_bad;
1674 }
1675
1676 out_good:
1677 ret = true;
1678
1679 out:
1680 key_control->thoff = min_t(u16, nhoff, skb ? skb->len : hlen);
1681 key_basic->n_proto = proto;
1682 key_basic->ip_proto = ip_proto;
1683
1684 return ret;
1685
1686 out_bad:
1687 ret = false;
1688 goto out;
1689 }
1690 EXPORT_SYMBOL(__skb_flow_dissect);
1691
1692 static siphash_aligned_key_t hashrnd;
1693 static __always_inline void __flow_hash_secret_init(void)
1694 {
1695 net_get_random_once(&hashrnd, sizeof(hashrnd));
1696 }
1697
1698 static const void *flow_keys_hash_start(const struct flow_keys *flow)
1699 {
1700 BUILD_BUG_ON(FLOW_KEYS_HASH_OFFSET % SIPHASH_ALIGNMENT);
1701 return &flow->FLOW_KEYS_HASH_START_FIELD;
1702 }
1703
1704 static inline size_t flow_keys_hash_length(const struct flow_keys *flow)
1705 {
1706 size_t diff = FLOW_KEYS_HASH_OFFSET + sizeof(flow->addrs);
1707
1708 BUILD_BUG_ON((sizeof(*flow) - FLOW_KEYS_HASH_OFFSET) % sizeof(u32));
1709
1710 switch (flow->control.addr_type) {
1711 case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1712 diff -= sizeof(flow->addrs.v4addrs);
1713 break;
1714 case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1715 diff -= sizeof(flow->addrs.v6addrs);
1716 break;
1717 case FLOW_DISSECTOR_KEY_TIPC:
1718 diff -= sizeof(flow->addrs.tipckey);
1719 break;
1720 }
1721 return sizeof(*flow) - diff;
1722 }
1723
1724 __be32 flow_get_u32_src(const struct flow_keys *flow)
1725 {
1726 switch (flow->control.addr_type) {
1727 case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1728 return flow->addrs.v4addrs.src;
1729 case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1730 return (__force __be32)ipv6_addr_hash(
1731 &flow->addrs.v6addrs.src);
1732 case FLOW_DISSECTOR_KEY_TIPC:
1733 return flow->addrs.tipckey.key;
1734 default:
1735 return 0;
1736 }
1737 }
1738 EXPORT_SYMBOL(flow_get_u32_src);
1739
1740 __be32 flow_get_u32_dst(const struct flow_keys *flow)
1741 {
1742 switch (flow->control.addr_type) {
1743 case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1744 return flow->addrs.v4addrs.dst;
1745 case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1746 return (__force __be32)ipv6_addr_hash(
1747 &flow->addrs.v6addrs.dst);
1748 default:
1749 return 0;
1750 }
1751 }
1752 EXPORT_SYMBOL(flow_get_u32_dst);
1753
1754 /* Sort the source and destination IP and the ports,
1755 * to have consistent hash within the two directions
1756 */
1757 static inline void __flow_hash_consistentify(struct flow_keys *keys)
1758 {
1759 int addr_diff, i;
1760
1761 switch (keys->control.addr_type) {
1762 case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1763 if ((__force u32)keys->addrs.v4addrs.dst <
1764 (__force u32)keys->addrs.v4addrs.src)
1765 swap(keys->addrs.v4addrs.src, keys->addrs.v4addrs.dst);
1766
1767 if ((__force u16)keys->ports.dst <
1768 (__force u16)keys->ports.src) {
1769 swap(keys->ports.src, keys->ports.dst);
1770 }
1771 break;
1772 case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1773 addr_diff = memcmp(&keys->addrs.v6addrs.dst,
1774 &keys->addrs.v6addrs.src,
1775 sizeof(keys->addrs.v6addrs.dst));
1776 if (addr_diff < 0) {
1777 for (i = 0; i < 4; i++)
1778 swap(keys->addrs.v6addrs.src.s6_addr32[i],
1779 keys->addrs.v6addrs.dst.s6_addr32[i]);
1780 }
1781 if ((__force u16)keys->ports.dst <
1782 (__force u16)keys->ports.src) {
1783 swap(keys->ports.src, keys->ports.dst);
1784 }
1785 break;
1786 }
1787 }
1788
1789 static inline u32 __flow_hash_from_keys(struct flow_keys *keys,
1790 const siphash_key_t *keyval)
1791 {
1792 u32 hash;
1793
1794 __flow_hash_consistentify(keys);
1795
1796 hash = siphash(flow_keys_hash_start(keys),
1797 flow_keys_hash_length(keys), keyval);
1798 if (!hash)
1799 hash = 1;
1800
1801 return hash;
1802 }
1803
1804 u32 flow_hash_from_keys(struct flow_keys *keys)
1805 {
1806 __flow_hash_secret_init();
1807 return __flow_hash_from_keys(keys, &hashrnd);
1808 }
1809 EXPORT_SYMBOL(flow_hash_from_keys);
1810
1811 u32 flow_hash_from_keys_seed(struct flow_keys *keys,
1812 const siphash_key_t *keyval)
1813 {
1814 return __flow_hash_from_keys(keys, keyval);
1815 }
1816 EXPORT_SYMBOL(flow_hash_from_keys_seed);
1817
1818 static inline u32 ___skb_get_hash(const struct sk_buff *skb,
1819 struct flow_keys *keys,
1820 const siphash_key_t *keyval)
1821 {
1822 skb_flow_dissect_flow_keys(skb, keys,
1823 FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
1824
1825 return __flow_hash_from_keys(keys, keyval);
1826 }
1827
1828 struct _flow_keys_digest_data {
1829 __be16 n_proto;
1830 u8 ip_proto;
1831 u8 padding;
1832 __be32 ports;
1833 __be32 src;
1834 __be32 dst;
1835 };
1836
1837 void make_flow_keys_digest(struct flow_keys_digest *digest,
1838 const struct flow_keys *flow)
1839 {
1840 struct _flow_keys_digest_data *data =
1841 (struct _flow_keys_digest_data *)digest;
1842
1843 BUILD_BUG_ON(sizeof(*data) > sizeof(*digest));
1844
1845 memset(digest, 0, sizeof(*digest));
1846
1847 data->n_proto = flow->basic.n_proto;
1848 data->ip_proto = flow->basic.ip_proto;
1849 data->ports = flow->ports.ports;
1850 data->src = flow->addrs.v4addrs.src;
1851 data->dst = flow->addrs.v4addrs.dst;
1852 }
1853 EXPORT_SYMBOL(make_flow_keys_digest);
1854
1855 static struct flow_dissector flow_keys_dissector_symmetric __read_mostly;
1856
1857 u32 __skb_get_hash_symmetric_net(const struct net *net, const struct sk_buff *skb)
1858 {
1859 struct flow_keys keys;
1860
1861 __flow_hash_secret_init();
1862
1863 memset(&keys, 0, sizeof(keys));
1864 __skb_flow_dissect(net, skb, &flow_keys_dissector_symmetric,
1865 &keys, NULL, 0, 0, 0, 0);
1866
1867 return __flow_hash_from_keys(&keys, &hashrnd);
1868 }
1869 EXPORT_SYMBOL_GPL(__skb_get_hash_symmetric_net);
1870
1871 /**
1872 * __skb_get_hash_net: calculate a flow hash
1873 * @net: associated network namespace, derived from @skb if NULL
1874 * @skb: sk_buff to calculate flow hash from
1875 *
1876 * This function calculates a flow hash based on src/dst addresses
1877 * and src/dst port numbers. Sets hash in skb to non-zero hash value
1878 * on success, zero indicates no valid hash. Also, sets l4_hash in skb
1879 * if hash is a canonical 4-tuple hash over transport ports.
1880 */
1881 void __skb_get_hash_net(const struct net *net, struct sk_buff *skb)
1882 {
1883 struct flow_keys keys;
1884 u32 hash;
1885
1886 memset(&keys, 0, sizeof(keys));
1887
1888 __skb_flow_dissect(net, skb, &flow_keys_dissector,
1889 &keys, NULL, 0, 0, 0,
1890 FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
1891
1892 __flow_hash_secret_init();
1893
1894 hash = __flow_hash_from_keys(&keys, &hashrnd);
1895
1896 __skb_set_sw_hash(skb, hash, flow_keys_have_l4(&keys));
1897 }
1898 EXPORT_SYMBOL(__skb_get_hash_net);
1899
1900 __u32 skb_get_hash_perturb(const struct sk_buff *skb,
1901 const siphash_key_t *perturb)
1902 {
1903 struct flow_keys keys;
1904
1905 return ___skb_get_hash(skb, &keys, perturb);
1906 }
1907 EXPORT_SYMBOL(skb_get_hash_perturb);
1908
1909 u32 __skb_get_poff(const struct sk_buff *skb, const void *data,
1910 const struct flow_keys_basic *keys, int hlen)
1911 {
1912 u32 poff = keys->control.thoff;
1913
1914 /* skip L4 headers for fragments after the first */
1915 if ((keys->control.flags & FLOW_DIS_IS_FRAGMENT) &&
1916 !(keys->control.flags & FLOW_DIS_FIRST_FRAG))
1917 return poff;
1918
1919 switch (keys->basic.ip_proto) {
1920 case IPPROTO_TCP: {
1921 /* access doff as u8 to avoid unaligned access */
1922 const u8 *doff;
1923 u8 _doff;
1924
1925 doff = __skb_header_pointer(skb, poff + 12, sizeof(_doff),
1926 data, hlen, &_doff);
1927 if (!doff)
1928 return poff;
1929
1930 poff += max_t(u32, sizeof(struct tcphdr), (*doff & 0xF0) >> 2);
1931 break;
1932 }
1933 case IPPROTO_UDP:
1934 case IPPROTO_UDPLITE:
1935 poff += sizeof(struct udphdr);
1936 break;
1937 /* For the rest, we do not really care about header
1938 * extensions at this point for now.
1939 */
1940 case IPPROTO_ICMP:
1941 poff += sizeof(struct icmphdr);
1942 break;
1943 case IPPROTO_ICMPV6:
1944 poff += sizeof(struct icmp6hdr);
1945 break;
1946 case IPPROTO_IGMP:
1947 poff += sizeof(struct igmphdr);
1948 break;
1949 case IPPROTO_DCCP:
1950 poff += sizeof(struct dccp_hdr);
1951 break;
1952 case IPPROTO_SCTP:
1953 poff += sizeof(struct sctphdr);
1954 break;
1955 }
1956
1957 return poff;
1958 }
1959
1960 /**
1961 * skb_get_poff - get the offset to the payload
1962 * @skb: sk_buff to get the payload offset from
1963 *
1964 * The function will get the offset to the payload as far as it could
1965 * be dissected. The main user is currently BPF, so that we can dynamically
1966 * truncate packets without needing to push actual payload to the user
1967 * space and can analyze headers only, instead.
1968 */
1969 u32 skb_get_poff(const struct sk_buff *skb)
1970 {
1971 struct flow_keys_basic keys;
1972
1973 if (!skb_flow_dissect_flow_keys_basic(NULL, skb, &keys,
1974 NULL, 0, 0, 0, 0))
1975 return 0;
1976
1977 return __skb_get_poff(skb, skb->data, &keys, skb_headlen(skb));
1978 }
1979
1980 __u32 __get_hash_from_flowi6(const struct flowi6 *fl6, struct flow_keys *keys)
1981 {
1982 memset(keys, 0, sizeof(*keys));
1983
1984 memcpy(&keys->addrs.v6addrs.src, &fl6->saddr,
1985 sizeof(keys->addrs.v6addrs.src));
1986 memcpy(&keys->addrs.v6addrs.dst, &fl6->daddr,
1987 sizeof(keys->addrs.v6addrs.dst));
1988 keys->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
1989 keys->ports.src = fl6->fl6_sport;
1990 keys->ports.dst = fl6->fl6_dport;
1991 keys->keyid.keyid = fl6->fl6_gre_key;
1992 keys->tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);
1993 keys->basic.ip_proto = fl6->flowi6_proto;
1994
1995 return flow_hash_from_keys(keys);
1996 }
1997 EXPORT_SYMBOL(__get_hash_from_flowi6);
1998
1999 static const struct flow_dissector_key flow_keys_dissector_keys[] = {
2000 {
2001 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
2002 .offset = offsetof(struct flow_keys, control),
2003 },
2004 {
2005 .key_id = FLOW_DISSECTOR_KEY_BASIC,
2006 .offset = offsetof(struct flow_keys, basic),
2007 },
2008 {
2009 .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
2010 .offset = offsetof(struct flow_keys, addrs.v4addrs),
2011 },
2012 {
2013 .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
2014 .offset = offsetof(struct flow_keys, addrs.v6addrs),
2015 },
2016 {
2017 .key_id = FLOW_DISSECTOR_KEY_TIPC,
2018 .offset = offsetof(struct flow_keys, addrs.tipckey),
2019 },
2020 {
2021 .key_id = FLOW_DISSECTOR_KEY_PORTS,
2022 .offset = offsetof(struct flow_keys, ports),
2023 },
2024 {
2025 .key_id = FLOW_DISSECTOR_KEY_VLAN,
2026 .offset = offsetof(struct flow_keys, vlan),
2027 },
2028 {
2029 .key_id = FLOW_DISSECTOR_KEY_FLOW_LABEL,
2030 .offset = offsetof(struct flow_keys, tags),
2031 },
2032 {
2033 .key_id = FLOW_DISSECTOR_KEY_GRE_KEYID,
2034 .offset = offsetof(struct flow_keys, keyid),
2035 },
2036 };
2037
2038 static const struct flow_dissector_key flow_keys_dissector_symmetric_keys[] = {
2039 {
2040 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
2041 .offset = offsetof(struct flow_keys, control),
2042 },
2043 {
2044 .key_id = FLOW_DISSECTOR_KEY_BASIC,
2045 .offset = offsetof(struct flow_keys, basic),
2046 },
2047 {
2048 .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
2049 .offset = offsetof(struct flow_keys, addrs.v4addrs),
2050 },
2051 {
2052 .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
2053 .offset = offsetof(struct flow_keys, addrs.v6addrs),
2054 },
2055 {
2056 .key_id = FLOW_DISSECTOR_KEY_PORTS,
2057 .offset = offsetof(struct flow_keys, ports),
2058 },
2059 };
2060
2061 static const struct flow_dissector_key flow_keys_basic_dissector_keys[] = {
2062 {
2063 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
2064 .offset = offsetof(struct flow_keys, control),
2065 },
2066 {
2067 .key_id = FLOW_DISSECTOR_KEY_BASIC,
2068 .offset = offsetof(struct flow_keys, basic),
2069 },
2070 };
2071
2072 struct flow_dissector flow_keys_dissector __read_mostly;
2073 EXPORT_SYMBOL(flow_keys_dissector);
2074
2075 struct flow_dissector flow_keys_basic_dissector __read_mostly;
2076 EXPORT_SYMBOL(flow_keys_basic_dissector);
2077
2078 static int __init init_default_flow_dissectors(void)
2079 {
2080 skb_flow_dissector_init(&flow_keys_dissector,
2081 flow_keys_dissector_keys,
2082 ARRAY_SIZE(flow_keys_dissector_keys));
2083 skb_flow_dissector_init(&flow_keys_dissector_symmetric,
2084 flow_keys_dissector_symmetric_keys,
2085 ARRAY_SIZE(flow_keys_dissector_symmetric_keys));
2086 skb_flow_dissector_init(&flow_keys_basic_dissector,
2087 flow_keys_basic_dissector_keys,
2088 ARRAY_SIZE(flow_keys_basic_dissector_keys));
2089 return 0;
2090 }
2091 core_initcall(init_default_flow_dissectors);
2092
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