Merge branch 'address-masking'
[linux-2.6-microblaze.git] / net / core / flow_dissector.c
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);