drm/amdgpu/vg20:Restruct uvd to support multiple uvds
[muen/linux.git] / net / core / flow_dissector.c
1 #include <linux/kernel.h>
2 #include <linux/skbuff.h>
3 #include <linux/export.h>
4 #include <linux/ip.h>
5 #include <linux/ipv6.h>
6 #include <linux/if_vlan.h>
7 #include <net/dsa.h>
8 #include <net/dst_metadata.h>
9 #include <net/ip.h>
10 #include <net/ipv6.h>
11 #include <net/gre.h>
12 #include <net/pptp.h>
13 #include <net/tipc.h>
14 #include <linux/igmp.h>
15 #include <linux/icmp.h>
16 #include <linux/sctp.h>
17 #include <linux/dccp.h>
18 #include <linux/if_tunnel.h>
19 #include <linux/if_pppox.h>
20 #include <linux/ppp_defs.h>
21 #include <linux/stddef.h>
22 #include <linux/if_ether.h>
23 #include <linux/mpls.h>
24 #include <linux/tcp.h>
25 #include <net/flow_dissector.h>
26 #include <scsi/fc/fc_fcoe.h>
27 #include <uapi/linux/batadv_packet.h>
28
29 static void dissector_set_key(struct flow_dissector *flow_dissector,
30                               enum flow_dissector_key_id key_id)
31 {
32         flow_dissector->used_keys |= (1 << key_id);
33 }
34
35 void skb_flow_dissector_init(struct flow_dissector *flow_dissector,
36                              const struct flow_dissector_key *key,
37                              unsigned int key_count)
38 {
39         unsigned int i;
40
41         memset(flow_dissector, 0, sizeof(*flow_dissector));
42
43         for (i = 0; i < key_count; i++, key++) {
44                 /* User should make sure that every key target offset is withing
45                  * boundaries of unsigned short.
46                  */
47                 BUG_ON(key->offset > USHRT_MAX);
48                 BUG_ON(dissector_uses_key(flow_dissector,
49                                           key->key_id));
50
51                 dissector_set_key(flow_dissector, key->key_id);
52                 flow_dissector->offset[key->key_id] = key->offset;
53         }
54
55         /* Ensure that the dissector always includes control and basic key.
56          * That way we are able to avoid handling lack of these in fast path.
57          */
58         BUG_ON(!dissector_uses_key(flow_dissector,
59                                    FLOW_DISSECTOR_KEY_CONTROL));
60         BUG_ON(!dissector_uses_key(flow_dissector,
61                                    FLOW_DISSECTOR_KEY_BASIC));
62 }
63 EXPORT_SYMBOL(skb_flow_dissector_init);
64
65 /**
66  * skb_flow_get_be16 - extract be16 entity
67  * @skb: sk_buff to extract from
68  * @poff: offset to extract at
69  * @data: raw buffer pointer to the packet
70  * @hlen: packet header length
71  *
72  * The function will try to retrieve a be32 entity at
73  * offset poff
74  */
75 static __be16 skb_flow_get_be16(const struct sk_buff *skb, int poff,
76                                 void *data, int hlen)
77 {
78         __be16 *u, _u;
79
80         u = __skb_header_pointer(skb, poff, sizeof(_u), data, hlen, &_u);
81         if (u)
82                 return *u;
83
84         return 0;
85 }
86
87 /**
88  * __skb_flow_get_ports - extract the upper layer ports and return them
89  * @skb: sk_buff to extract the ports from
90  * @thoff: transport header offset
91  * @ip_proto: protocol for which to get port offset
92  * @data: raw buffer pointer to the packet, if NULL use skb->data
93  * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
94  *
95  * The function will try to retrieve the ports at offset thoff + poff where poff
96  * is the protocol port offset returned from proto_ports_offset
97  */
98 __be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto,
99                             void *data, int hlen)
100 {
101         int poff = proto_ports_offset(ip_proto);
102
103         if (!data) {
104                 data = skb->data;
105                 hlen = skb_headlen(skb);
106         }
107
108         if (poff >= 0) {
109                 __be32 *ports, _ports;
110
111                 ports = __skb_header_pointer(skb, thoff + poff,
112                                              sizeof(_ports), data, hlen, &_ports);
113                 if (ports)
114                         return *ports;
115         }
116
117         return 0;
118 }
119 EXPORT_SYMBOL(__skb_flow_get_ports);
120
121 static void
122 skb_flow_dissect_set_enc_addr_type(enum flow_dissector_key_id type,
123                                    struct flow_dissector *flow_dissector,
124                                    void *target_container)
125 {
126         struct flow_dissector_key_control *ctrl;
127
128         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_CONTROL))
129                 return;
130
131         ctrl = skb_flow_dissector_target(flow_dissector,
132                                          FLOW_DISSECTOR_KEY_ENC_CONTROL,
133                                          target_container);
134         ctrl->addr_type = type;
135 }
136
137 void
138 skb_flow_dissect_tunnel_info(const struct sk_buff *skb,
139                              struct flow_dissector *flow_dissector,
140                              void *target_container)
141 {
142         struct ip_tunnel_info *info;
143         struct ip_tunnel_key *key;
144
145         /* A quick check to see if there might be something to do. */
146         if (!dissector_uses_key(flow_dissector,
147                                 FLOW_DISSECTOR_KEY_ENC_KEYID) &&
148             !dissector_uses_key(flow_dissector,
149                                 FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS) &&
150             !dissector_uses_key(flow_dissector,
151                                 FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS) &&
152             !dissector_uses_key(flow_dissector,
153                                 FLOW_DISSECTOR_KEY_ENC_CONTROL) &&
154             !dissector_uses_key(flow_dissector,
155                                 FLOW_DISSECTOR_KEY_ENC_PORTS))
156                 return;
157
158         info = skb_tunnel_info(skb);
159         if (!info)
160                 return;
161
162         key = &info->key;
163
164         switch (ip_tunnel_info_af(info)) {
165         case AF_INET:
166                 skb_flow_dissect_set_enc_addr_type(FLOW_DISSECTOR_KEY_IPV4_ADDRS,
167                                                    flow_dissector,
168                                                    target_container);
169                 if (dissector_uses_key(flow_dissector,
170                                        FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS)) {
171                         struct flow_dissector_key_ipv4_addrs *ipv4;
172
173                         ipv4 = skb_flow_dissector_target(flow_dissector,
174                                                          FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS,
175                                                          target_container);
176                         ipv4->src = key->u.ipv4.src;
177                         ipv4->dst = key->u.ipv4.dst;
178                 }
179                 break;
180         case AF_INET6:
181                 skb_flow_dissect_set_enc_addr_type(FLOW_DISSECTOR_KEY_IPV6_ADDRS,
182                                                    flow_dissector,
183                                                    target_container);
184                 if (dissector_uses_key(flow_dissector,
185                                        FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS)) {
186                         struct flow_dissector_key_ipv6_addrs *ipv6;
187
188                         ipv6 = skb_flow_dissector_target(flow_dissector,
189                                                          FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS,
190                                                          target_container);
191                         ipv6->src = key->u.ipv6.src;
192                         ipv6->dst = key->u.ipv6.dst;
193                 }
194                 break;
195         }
196
197         if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_KEYID)) {
198                 struct flow_dissector_key_keyid *keyid;
199
200                 keyid = skb_flow_dissector_target(flow_dissector,
201                                                   FLOW_DISSECTOR_KEY_ENC_KEYID,
202                                                   target_container);
203                 keyid->keyid = tunnel_id_to_key32(key->tun_id);
204         }
205
206         if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_PORTS)) {
207                 struct flow_dissector_key_ports *tp;
208
209                 tp = skb_flow_dissector_target(flow_dissector,
210                                                FLOW_DISSECTOR_KEY_ENC_PORTS,
211                                                target_container);
212                 tp->src = key->tp_src;
213                 tp->dst = key->tp_dst;
214         }
215 }
216 EXPORT_SYMBOL(skb_flow_dissect_tunnel_info);
217
218 static enum flow_dissect_ret
219 __skb_flow_dissect_mpls(const struct sk_buff *skb,
220                         struct flow_dissector *flow_dissector,
221                         void *target_container, void *data, int nhoff, int hlen)
222 {
223         struct flow_dissector_key_keyid *key_keyid;
224         struct mpls_label *hdr, _hdr[2];
225         u32 entry, label;
226
227         if (!dissector_uses_key(flow_dissector,
228                                 FLOW_DISSECTOR_KEY_MPLS_ENTROPY) &&
229             !dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS))
230                 return FLOW_DISSECT_RET_OUT_GOOD;
231
232         hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
233                                    hlen, &_hdr);
234         if (!hdr)
235                 return FLOW_DISSECT_RET_OUT_BAD;
236
237         entry = ntohl(hdr[0].entry);
238         label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
239
240         if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS)) {
241                 struct flow_dissector_key_mpls *key_mpls;
242
243                 key_mpls = skb_flow_dissector_target(flow_dissector,
244                                                      FLOW_DISSECTOR_KEY_MPLS,
245                                                      target_container);
246                 key_mpls->mpls_label = label;
247                 key_mpls->mpls_ttl = (entry & MPLS_LS_TTL_MASK)
248                                         >> MPLS_LS_TTL_SHIFT;
249                 key_mpls->mpls_tc = (entry & MPLS_LS_TC_MASK)
250                                         >> MPLS_LS_TC_SHIFT;
251                 key_mpls->mpls_bos = (entry & MPLS_LS_S_MASK)
252                                         >> MPLS_LS_S_SHIFT;
253         }
254
255         if (label == MPLS_LABEL_ENTROPY) {
256                 key_keyid = skb_flow_dissector_target(flow_dissector,
257                                                       FLOW_DISSECTOR_KEY_MPLS_ENTROPY,
258                                                       target_container);
259                 key_keyid->keyid = hdr[1].entry & htonl(MPLS_LS_LABEL_MASK);
260         }
261         return FLOW_DISSECT_RET_OUT_GOOD;
262 }
263
264 static enum flow_dissect_ret
265 __skb_flow_dissect_arp(const struct sk_buff *skb,
266                        struct flow_dissector *flow_dissector,
267                        void *target_container, void *data, int nhoff, int hlen)
268 {
269         struct flow_dissector_key_arp *key_arp;
270         struct {
271                 unsigned char ar_sha[ETH_ALEN];
272                 unsigned char ar_sip[4];
273                 unsigned char ar_tha[ETH_ALEN];
274                 unsigned char ar_tip[4];
275         } *arp_eth, _arp_eth;
276         const struct arphdr *arp;
277         struct arphdr _arp;
278
279         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ARP))
280                 return FLOW_DISSECT_RET_OUT_GOOD;
281
282         arp = __skb_header_pointer(skb, nhoff, sizeof(_arp), data,
283                                    hlen, &_arp);
284         if (!arp)
285                 return FLOW_DISSECT_RET_OUT_BAD;
286
287         if (arp->ar_hrd != htons(ARPHRD_ETHER) ||
288             arp->ar_pro != htons(ETH_P_IP) ||
289             arp->ar_hln != ETH_ALEN ||
290             arp->ar_pln != 4 ||
291             (arp->ar_op != htons(ARPOP_REPLY) &&
292              arp->ar_op != htons(ARPOP_REQUEST)))
293                 return FLOW_DISSECT_RET_OUT_BAD;
294
295         arp_eth = __skb_header_pointer(skb, nhoff + sizeof(_arp),
296                                        sizeof(_arp_eth), data,
297                                        hlen, &_arp_eth);
298         if (!arp_eth)
299                 return FLOW_DISSECT_RET_OUT_BAD;
300
301         key_arp = skb_flow_dissector_target(flow_dissector,
302                                             FLOW_DISSECTOR_KEY_ARP,
303                                             target_container);
304
305         memcpy(&key_arp->sip, arp_eth->ar_sip, sizeof(key_arp->sip));
306         memcpy(&key_arp->tip, arp_eth->ar_tip, sizeof(key_arp->tip));
307
308         /* Only store the lower byte of the opcode;
309          * this covers ARPOP_REPLY and ARPOP_REQUEST.
310          */
311         key_arp->op = ntohs(arp->ar_op) & 0xff;
312
313         ether_addr_copy(key_arp->sha, arp_eth->ar_sha);
314         ether_addr_copy(key_arp->tha, arp_eth->ar_tha);
315
316         return FLOW_DISSECT_RET_OUT_GOOD;
317 }
318
319 static enum flow_dissect_ret
320 __skb_flow_dissect_gre(const struct sk_buff *skb,
321                        struct flow_dissector_key_control *key_control,
322                        struct flow_dissector *flow_dissector,
323                        void *target_container, void *data,
324                        __be16 *p_proto, int *p_nhoff, int *p_hlen,
325                        unsigned int flags)
326 {
327         struct flow_dissector_key_keyid *key_keyid;
328         struct gre_base_hdr *hdr, _hdr;
329         int offset = 0;
330         u16 gre_ver;
331
332         hdr = __skb_header_pointer(skb, *p_nhoff, sizeof(_hdr),
333                                    data, *p_hlen, &_hdr);
334         if (!hdr)
335                 return FLOW_DISSECT_RET_OUT_BAD;
336
337         /* Only look inside GRE without routing */
338         if (hdr->flags & GRE_ROUTING)
339                 return FLOW_DISSECT_RET_OUT_GOOD;
340
341         /* Only look inside GRE for version 0 and 1 */
342         gre_ver = ntohs(hdr->flags & GRE_VERSION);
343         if (gre_ver > 1)
344                 return FLOW_DISSECT_RET_OUT_GOOD;
345
346         *p_proto = hdr->protocol;
347         if (gre_ver) {
348                 /* Version1 must be PPTP, and check the flags */
349                 if (!(*p_proto == GRE_PROTO_PPP && (hdr->flags & GRE_KEY)))
350                         return FLOW_DISSECT_RET_OUT_GOOD;
351         }
352
353         offset += sizeof(struct gre_base_hdr);
354
355         if (hdr->flags & GRE_CSUM)
356                 offset += sizeof(((struct gre_full_hdr *) 0)->csum) +
357                           sizeof(((struct gre_full_hdr *) 0)->reserved1);
358
359         if (hdr->flags & GRE_KEY) {
360                 const __be32 *keyid;
361                 __be32 _keyid;
362
363                 keyid = __skb_header_pointer(skb, *p_nhoff + offset,
364                                              sizeof(_keyid),
365                                              data, *p_hlen, &_keyid);
366                 if (!keyid)
367                         return FLOW_DISSECT_RET_OUT_BAD;
368
369                 if (dissector_uses_key(flow_dissector,
370                                        FLOW_DISSECTOR_KEY_GRE_KEYID)) {
371                         key_keyid = skb_flow_dissector_target(flow_dissector,
372                                                               FLOW_DISSECTOR_KEY_GRE_KEYID,
373                                                               target_container);
374                         if (gre_ver == 0)
375                                 key_keyid->keyid = *keyid;
376                         else
377                                 key_keyid->keyid = *keyid & GRE_PPTP_KEY_MASK;
378                 }
379                 offset += sizeof(((struct gre_full_hdr *) 0)->key);
380         }
381
382         if (hdr->flags & GRE_SEQ)
383                 offset += sizeof(((struct pptp_gre_header *) 0)->seq);
384
385         if (gre_ver == 0) {
386                 if (*p_proto == htons(ETH_P_TEB)) {
387                         const struct ethhdr *eth;
388                         struct ethhdr _eth;
389
390                         eth = __skb_header_pointer(skb, *p_nhoff + offset,
391                                                    sizeof(_eth),
392                                                    data, *p_hlen, &_eth);
393                         if (!eth)
394                                 return FLOW_DISSECT_RET_OUT_BAD;
395                         *p_proto = eth->h_proto;
396                         offset += sizeof(*eth);
397
398                         /* Cap headers that we access via pointers at the
399                          * end of the Ethernet header as our maximum alignment
400                          * at that point is only 2 bytes.
401                          */
402                         if (NET_IP_ALIGN)
403                                 *p_hlen = *p_nhoff + offset;
404                 }
405         } else { /* version 1, must be PPTP */
406                 u8 _ppp_hdr[PPP_HDRLEN];
407                 u8 *ppp_hdr;
408
409                 if (hdr->flags & GRE_ACK)
410                         offset += sizeof(((struct pptp_gre_header *) 0)->ack);
411
412                 ppp_hdr = __skb_header_pointer(skb, *p_nhoff + offset,
413                                                sizeof(_ppp_hdr),
414                                                data, *p_hlen, _ppp_hdr);
415                 if (!ppp_hdr)
416                         return FLOW_DISSECT_RET_OUT_BAD;
417
418                 switch (PPP_PROTOCOL(ppp_hdr)) {
419                 case PPP_IP:
420                         *p_proto = htons(ETH_P_IP);
421                         break;
422                 case PPP_IPV6:
423                         *p_proto = htons(ETH_P_IPV6);
424                         break;
425                 default:
426                         /* Could probably catch some more like MPLS */
427                         break;
428                 }
429
430                 offset += PPP_HDRLEN;
431         }
432
433         *p_nhoff += offset;
434         key_control->flags |= FLOW_DIS_ENCAPSULATION;
435         if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
436                 return FLOW_DISSECT_RET_OUT_GOOD;
437
438         return FLOW_DISSECT_RET_PROTO_AGAIN;
439 }
440
441 /**
442  * __skb_flow_dissect_batadv() - dissect batman-adv header
443  * @skb: sk_buff to with the batman-adv header
444  * @key_control: flow dissectors control key
445  * @data: raw buffer pointer to the packet, if NULL use skb->data
446  * @p_proto: pointer used to update the protocol to process next
447  * @p_nhoff: pointer used to update inner network header offset
448  * @hlen: packet header length
449  * @flags: any combination of FLOW_DISSECTOR_F_*
450  *
451  * ETH_P_BATMAN packets are tried to be dissected. Only
452  * &struct batadv_unicast packets are actually processed because they contain an
453  * inner ethernet header and are usually followed by actual network header. This
454  * allows the flow dissector to continue processing the packet.
455  *
456  * Return: FLOW_DISSECT_RET_PROTO_AGAIN when &struct batadv_unicast was found,
457  *  FLOW_DISSECT_RET_OUT_GOOD when dissector should stop after encapsulation,
458  *  otherwise FLOW_DISSECT_RET_OUT_BAD
459  */
460 static enum flow_dissect_ret
461 __skb_flow_dissect_batadv(const struct sk_buff *skb,
462                           struct flow_dissector_key_control *key_control,
463                           void *data, __be16 *p_proto, int *p_nhoff, int hlen,
464                           unsigned int flags)
465 {
466         struct {
467                 struct batadv_unicast_packet batadv_unicast;
468                 struct ethhdr eth;
469         } *hdr, _hdr;
470
471         hdr = __skb_header_pointer(skb, *p_nhoff, sizeof(_hdr), data, hlen,
472                                    &_hdr);
473         if (!hdr)
474                 return FLOW_DISSECT_RET_OUT_BAD;
475
476         if (hdr->batadv_unicast.version != BATADV_COMPAT_VERSION)
477                 return FLOW_DISSECT_RET_OUT_BAD;
478
479         if (hdr->batadv_unicast.packet_type != BATADV_UNICAST)
480                 return FLOW_DISSECT_RET_OUT_BAD;
481
482         *p_proto = hdr->eth.h_proto;
483         *p_nhoff += sizeof(*hdr);
484
485         key_control->flags |= FLOW_DIS_ENCAPSULATION;
486         if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
487                 return FLOW_DISSECT_RET_OUT_GOOD;
488
489         return FLOW_DISSECT_RET_PROTO_AGAIN;
490 }
491
492 static void
493 __skb_flow_dissect_tcp(const struct sk_buff *skb,
494                        struct flow_dissector *flow_dissector,
495                        void *target_container, void *data, int thoff, int hlen)
496 {
497         struct flow_dissector_key_tcp *key_tcp;
498         struct tcphdr *th, _th;
499
500         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_TCP))
501                 return;
502
503         th = __skb_header_pointer(skb, thoff, sizeof(_th), data, hlen, &_th);
504         if (!th)
505                 return;
506
507         if (unlikely(__tcp_hdrlen(th) < sizeof(_th)))
508                 return;
509
510         key_tcp = skb_flow_dissector_target(flow_dissector,
511                                             FLOW_DISSECTOR_KEY_TCP,
512                                             target_container);
513         key_tcp->flags = (*(__be16 *) &tcp_flag_word(th) & htons(0x0FFF));
514 }
515
516 static void
517 __skb_flow_dissect_ipv4(const struct sk_buff *skb,
518                         struct flow_dissector *flow_dissector,
519                         void *target_container, void *data, const struct iphdr *iph)
520 {
521         struct flow_dissector_key_ip *key_ip;
522
523         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
524                 return;
525
526         key_ip = skb_flow_dissector_target(flow_dissector,
527                                            FLOW_DISSECTOR_KEY_IP,
528                                            target_container);
529         key_ip->tos = iph->tos;
530         key_ip->ttl = iph->ttl;
531 }
532
533 static void
534 __skb_flow_dissect_ipv6(const struct sk_buff *skb,
535                         struct flow_dissector *flow_dissector,
536                         void *target_container, void *data, const struct ipv6hdr *iph)
537 {
538         struct flow_dissector_key_ip *key_ip;
539
540         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
541                 return;
542
543         key_ip = skb_flow_dissector_target(flow_dissector,
544                                            FLOW_DISSECTOR_KEY_IP,
545                                            target_container);
546         key_ip->tos = ipv6_get_dsfield(iph);
547         key_ip->ttl = iph->hop_limit;
548 }
549
550 /* Maximum number of protocol headers that can be parsed in
551  * __skb_flow_dissect
552  */
553 #define MAX_FLOW_DISSECT_HDRS   15
554
555 static bool skb_flow_dissect_allowed(int *num_hdrs)
556 {
557         ++*num_hdrs;
558
559         return (*num_hdrs <= MAX_FLOW_DISSECT_HDRS);
560 }
561
562 /**
563  * __skb_flow_dissect - extract the flow_keys struct and return it
564  * @skb: sk_buff to extract the flow from, can be NULL if the rest are specified
565  * @flow_dissector: list of keys to dissect
566  * @target_container: target structure to put dissected values into
567  * @data: raw buffer pointer to the packet, if NULL use skb->data
568  * @proto: protocol for which to get the flow, if @data is NULL use skb->protocol
569  * @nhoff: network header offset, if @data is NULL use skb_network_offset(skb)
570  * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
571  *
572  * The function will try to retrieve individual keys into target specified
573  * by flow_dissector from either the skbuff or a raw buffer specified by the
574  * rest parameters.
575  *
576  * Caller must take care of zeroing target container memory.
577  */
578 bool __skb_flow_dissect(const struct sk_buff *skb,
579                         struct flow_dissector *flow_dissector,
580                         void *target_container,
581                         void *data, __be16 proto, int nhoff, int hlen,
582                         unsigned int flags)
583 {
584         struct flow_dissector_key_control *key_control;
585         struct flow_dissector_key_basic *key_basic;
586         struct flow_dissector_key_addrs *key_addrs;
587         struct flow_dissector_key_ports *key_ports;
588         struct flow_dissector_key_icmp *key_icmp;
589         struct flow_dissector_key_tags *key_tags;
590         struct flow_dissector_key_vlan *key_vlan;
591         enum flow_dissect_ret fdret;
592         bool skip_vlan = false;
593         int num_hdrs = 0;
594         u8 ip_proto = 0;
595         bool ret;
596
597         if (!data) {
598                 data = skb->data;
599                 proto = skb_vlan_tag_present(skb) ?
600                          skb->vlan_proto : skb->protocol;
601                 nhoff = skb_network_offset(skb);
602                 hlen = skb_headlen(skb);
603 #if IS_ENABLED(CONFIG_NET_DSA)
604                 if (unlikely(skb->dev && netdev_uses_dsa(skb->dev))) {
605                         const struct dsa_device_ops *ops;
606                         int offset;
607
608                         ops = skb->dev->dsa_ptr->tag_ops;
609                         if (ops->flow_dissect &&
610                             !ops->flow_dissect(skb, &proto, &offset)) {
611                                 hlen -= offset;
612                                 nhoff += offset;
613                         }
614                 }
615 #endif
616         }
617
618         /* It is ensured by skb_flow_dissector_init() that control key will
619          * be always present.
620          */
621         key_control = skb_flow_dissector_target(flow_dissector,
622                                                 FLOW_DISSECTOR_KEY_CONTROL,
623                                                 target_container);
624
625         /* It is ensured by skb_flow_dissector_init() that basic key will
626          * be always present.
627          */
628         key_basic = skb_flow_dissector_target(flow_dissector,
629                                               FLOW_DISSECTOR_KEY_BASIC,
630                                               target_container);
631
632         if (dissector_uses_key(flow_dissector,
633                                FLOW_DISSECTOR_KEY_ETH_ADDRS)) {
634                 struct ethhdr *eth = eth_hdr(skb);
635                 struct flow_dissector_key_eth_addrs *key_eth_addrs;
636
637                 key_eth_addrs = skb_flow_dissector_target(flow_dissector,
638                                                           FLOW_DISSECTOR_KEY_ETH_ADDRS,
639                                                           target_container);
640                 memcpy(key_eth_addrs, &eth->h_dest, sizeof(*key_eth_addrs));
641         }
642
643 proto_again:
644         fdret = FLOW_DISSECT_RET_CONTINUE;
645
646         switch (proto) {
647         case htons(ETH_P_IP): {
648                 const struct iphdr *iph;
649                 struct iphdr _iph;
650
651                 iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
652                 if (!iph || iph->ihl < 5) {
653                         fdret = FLOW_DISSECT_RET_OUT_BAD;
654                         break;
655                 }
656
657                 nhoff += iph->ihl * 4;
658
659                 ip_proto = iph->protocol;
660
661                 if (dissector_uses_key(flow_dissector,
662                                        FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
663                         key_addrs = skb_flow_dissector_target(flow_dissector,
664                                                               FLOW_DISSECTOR_KEY_IPV4_ADDRS,
665                                                               target_container);
666
667                         memcpy(&key_addrs->v4addrs, &iph->saddr,
668                                sizeof(key_addrs->v4addrs));
669                         key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
670                 }
671
672                 if (ip_is_fragment(iph)) {
673                         key_control->flags |= FLOW_DIS_IS_FRAGMENT;
674
675                         if (iph->frag_off & htons(IP_OFFSET)) {
676                                 fdret = FLOW_DISSECT_RET_OUT_GOOD;
677                                 break;
678                         } else {
679                                 key_control->flags |= FLOW_DIS_FIRST_FRAG;
680                                 if (!(flags &
681                                       FLOW_DISSECTOR_F_PARSE_1ST_FRAG)) {
682                                         fdret = FLOW_DISSECT_RET_OUT_GOOD;
683                                         break;
684                                 }
685                         }
686                 }
687
688                 __skb_flow_dissect_ipv4(skb, flow_dissector,
689                                         target_container, data, iph);
690
691                 if (flags & FLOW_DISSECTOR_F_STOP_AT_L3) {
692                         fdret = FLOW_DISSECT_RET_OUT_GOOD;
693                         break;
694                 }
695
696                 break;
697         }
698         case htons(ETH_P_IPV6): {
699                 const struct ipv6hdr *iph;
700                 struct ipv6hdr _iph;
701
702                 iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
703                 if (!iph) {
704                         fdret = FLOW_DISSECT_RET_OUT_BAD;
705                         break;
706                 }
707
708                 ip_proto = iph->nexthdr;
709                 nhoff += sizeof(struct ipv6hdr);
710
711                 if (dissector_uses_key(flow_dissector,
712                                        FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
713                         key_addrs = skb_flow_dissector_target(flow_dissector,
714                                                               FLOW_DISSECTOR_KEY_IPV6_ADDRS,
715                                                               target_container);
716
717                         memcpy(&key_addrs->v6addrs, &iph->saddr,
718                                sizeof(key_addrs->v6addrs));
719                         key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
720                 }
721
722                 if ((dissector_uses_key(flow_dissector,
723                                         FLOW_DISSECTOR_KEY_FLOW_LABEL) ||
724                      (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL)) &&
725                     ip6_flowlabel(iph)) {
726                         __be32 flow_label = ip6_flowlabel(iph);
727
728                         if (dissector_uses_key(flow_dissector,
729                                                FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
730                                 key_tags = skb_flow_dissector_target(flow_dissector,
731                                                                      FLOW_DISSECTOR_KEY_FLOW_LABEL,
732                                                                      target_container);
733                                 key_tags->flow_label = ntohl(flow_label);
734                         }
735                         if (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL) {
736                                 fdret = FLOW_DISSECT_RET_OUT_GOOD;
737                                 break;
738                         }
739                 }
740
741                 __skb_flow_dissect_ipv6(skb, flow_dissector,
742                                         target_container, data, iph);
743
744                 if (flags & FLOW_DISSECTOR_F_STOP_AT_L3)
745                         fdret = FLOW_DISSECT_RET_OUT_GOOD;
746
747                 break;
748         }
749         case htons(ETH_P_8021AD):
750         case htons(ETH_P_8021Q): {
751                 const struct vlan_hdr *vlan;
752                 struct vlan_hdr _vlan;
753                 bool vlan_tag_present = skb && skb_vlan_tag_present(skb);
754
755                 if (vlan_tag_present)
756                         proto = skb->protocol;
757
758                 if (!vlan_tag_present || eth_type_vlan(skb->protocol)) {
759                         vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan),
760                                                     data, hlen, &_vlan);
761                         if (!vlan) {
762                                 fdret = FLOW_DISSECT_RET_OUT_BAD;
763                                 break;
764                         }
765
766                         proto = vlan->h_vlan_encapsulated_proto;
767                         nhoff += sizeof(*vlan);
768                         if (skip_vlan) {
769                                 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
770                                 break;
771                         }
772                 }
773
774                 skip_vlan = true;
775                 if (dissector_uses_key(flow_dissector,
776                                        FLOW_DISSECTOR_KEY_VLAN)) {
777                         key_vlan = skb_flow_dissector_target(flow_dissector,
778                                                              FLOW_DISSECTOR_KEY_VLAN,
779                                                              target_container);
780
781                         if (vlan_tag_present) {
782                                 key_vlan->vlan_id = skb_vlan_tag_get_id(skb);
783                                 key_vlan->vlan_priority =
784                                         (skb_vlan_tag_get_prio(skb) >> VLAN_PRIO_SHIFT);
785                         } else {
786                                 key_vlan->vlan_id = ntohs(vlan->h_vlan_TCI) &
787                                         VLAN_VID_MASK;
788                                 key_vlan->vlan_priority =
789                                         (ntohs(vlan->h_vlan_TCI) &
790                                          VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
791                         }
792                 }
793
794                 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
795                 break;
796         }
797         case htons(ETH_P_PPP_SES): {
798                 struct {
799                         struct pppoe_hdr hdr;
800                         __be16 proto;
801                 } *hdr, _hdr;
802                 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
803                 if (!hdr) {
804                         fdret = FLOW_DISSECT_RET_OUT_BAD;
805                         break;
806                 }
807
808                 proto = hdr->proto;
809                 nhoff += PPPOE_SES_HLEN;
810                 switch (proto) {
811                 case htons(PPP_IP):
812                         proto = htons(ETH_P_IP);
813                         fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
814                         break;
815                 case htons(PPP_IPV6):
816                         proto = htons(ETH_P_IPV6);
817                         fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
818                         break;
819                 default:
820                         fdret = FLOW_DISSECT_RET_OUT_BAD;
821                         break;
822                 }
823                 break;
824         }
825         case htons(ETH_P_TIPC): {
826                 struct tipc_basic_hdr *hdr, _hdr;
827
828                 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr),
829                                            data, hlen, &_hdr);
830                 if (!hdr) {
831                         fdret = FLOW_DISSECT_RET_OUT_BAD;
832                         break;
833                 }
834
835                 if (dissector_uses_key(flow_dissector,
836                                        FLOW_DISSECTOR_KEY_TIPC)) {
837                         key_addrs = skb_flow_dissector_target(flow_dissector,
838                                                               FLOW_DISSECTOR_KEY_TIPC,
839                                                               target_container);
840                         key_addrs->tipckey.key = tipc_hdr_rps_key(hdr);
841                         key_control->addr_type = FLOW_DISSECTOR_KEY_TIPC;
842                 }
843                 fdret = FLOW_DISSECT_RET_OUT_GOOD;
844                 break;
845         }
846
847         case htons(ETH_P_MPLS_UC):
848         case htons(ETH_P_MPLS_MC):
849                 fdret = __skb_flow_dissect_mpls(skb, flow_dissector,
850                                                 target_container, data,
851                                                 nhoff, hlen);
852                 break;
853         case htons(ETH_P_FCOE):
854                 if ((hlen - nhoff) < FCOE_HEADER_LEN) {
855                         fdret = FLOW_DISSECT_RET_OUT_BAD;
856                         break;
857                 }
858
859                 nhoff += FCOE_HEADER_LEN;
860                 fdret = FLOW_DISSECT_RET_OUT_GOOD;
861                 break;
862
863         case htons(ETH_P_ARP):
864         case htons(ETH_P_RARP):
865                 fdret = __skb_flow_dissect_arp(skb, flow_dissector,
866                                                target_container, data,
867                                                nhoff, hlen);
868                 break;
869
870         case htons(ETH_P_BATMAN):
871                 fdret = __skb_flow_dissect_batadv(skb, key_control, data,
872                                                   &proto, &nhoff, hlen, flags);
873                 break;
874
875         default:
876                 fdret = FLOW_DISSECT_RET_OUT_BAD;
877                 break;
878         }
879
880         /* Process result of proto processing */
881         switch (fdret) {
882         case FLOW_DISSECT_RET_OUT_GOOD:
883                 goto out_good;
884         case FLOW_DISSECT_RET_PROTO_AGAIN:
885                 if (skb_flow_dissect_allowed(&num_hdrs))
886                         goto proto_again;
887                 goto out_good;
888         case FLOW_DISSECT_RET_CONTINUE:
889         case FLOW_DISSECT_RET_IPPROTO_AGAIN:
890                 break;
891         case FLOW_DISSECT_RET_OUT_BAD:
892         default:
893                 goto out_bad;
894         }
895
896 ip_proto_again:
897         fdret = FLOW_DISSECT_RET_CONTINUE;
898
899         switch (ip_proto) {
900         case IPPROTO_GRE:
901                 fdret = __skb_flow_dissect_gre(skb, key_control, flow_dissector,
902                                                target_container, data,
903                                                &proto, &nhoff, &hlen, flags);
904                 break;
905
906         case NEXTHDR_HOP:
907         case NEXTHDR_ROUTING:
908         case NEXTHDR_DEST: {
909                 u8 _opthdr[2], *opthdr;
910
911                 if (proto != htons(ETH_P_IPV6))
912                         break;
913
914                 opthdr = __skb_header_pointer(skb, nhoff, sizeof(_opthdr),
915                                               data, hlen, &_opthdr);
916                 if (!opthdr) {
917                         fdret = FLOW_DISSECT_RET_OUT_BAD;
918                         break;
919                 }
920
921                 ip_proto = opthdr[0];
922                 nhoff += (opthdr[1] + 1) << 3;
923
924                 fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
925                 break;
926         }
927         case NEXTHDR_FRAGMENT: {
928                 struct frag_hdr _fh, *fh;
929
930                 if (proto != htons(ETH_P_IPV6))
931                         break;
932
933                 fh = __skb_header_pointer(skb, nhoff, sizeof(_fh),
934                                           data, hlen, &_fh);
935
936                 if (!fh) {
937                         fdret = FLOW_DISSECT_RET_OUT_BAD;
938                         break;
939                 }
940
941                 key_control->flags |= FLOW_DIS_IS_FRAGMENT;
942
943                 nhoff += sizeof(_fh);
944                 ip_proto = fh->nexthdr;
945
946                 if (!(fh->frag_off & htons(IP6_OFFSET))) {
947                         key_control->flags |= FLOW_DIS_FIRST_FRAG;
948                         if (flags & FLOW_DISSECTOR_F_PARSE_1ST_FRAG) {
949                                 fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
950                                 break;
951                         }
952                 }
953
954                 fdret = FLOW_DISSECT_RET_OUT_GOOD;
955                 break;
956         }
957         case IPPROTO_IPIP:
958                 proto = htons(ETH_P_IP);
959
960                 key_control->flags |= FLOW_DIS_ENCAPSULATION;
961                 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
962                         fdret = FLOW_DISSECT_RET_OUT_GOOD;
963                         break;
964                 }
965
966                 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
967                 break;
968
969         case IPPROTO_IPV6:
970                 proto = htons(ETH_P_IPV6);
971
972                 key_control->flags |= FLOW_DIS_ENCAPSULATION;
973                 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
974                         fdret = FLOW_DISSECT_RET_OUT_GOOD;
975                         break;
976                 }
977
978                 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
979                 break;
980
981
982         case IPPROTO_MPLS:
983                 proto = htons(ETH_P_MPLS_UC);
984                 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
985                 break;
986
987         case IPPROTO_TCP:
988                 __skb_flow_dissect_tcp(skb, flow_dissector, target_container,
989                                        data, nhoff, hlen);
990                 break;
991
992         default:
993                 break;
994         }
995
996         if (dissector_uses_key(flow_dissector,
997                                FLOW_DISSECTOR_KEY_PORTS)) {
998                 key_ports = skb_flow_dissector_target(flow_dissector,
999                                                       FLOW_DISSECTOR_KEY_PORTS,
1000                                                       target_container);
1001                 key_ports->ports = __skb_flow_get_ports(skb, nhoff, ip_proto,
1002                                                         data, hlen);
1003         }
1004
1005         if (dissector_uses_key(flow_dissector,
1006                                FLOW_DISSECTOR_KEY_ICMP)) {
1007                 key_icmp = skb_flow_dissector_target(flow_dissector,
1008                                                      FLOW_DISSECTOR_KEY_ICMP,
1009                                                      target_container);
1010                 key_icmp->icmp = skb_flow_get_be16(skb, nhoff, data, hlen);
1011         }
1012
1013         /* Process result of IP proto processing */
1014         switch (fdret) {
1015         case FLOW_DISSECT_RET_PROTO_AGAIN:
1016                 if (skb_flow_dissect_allowed(&num_hdrs))
1017                         goto proto_again;
1018                 break;
1019         case FLOW_DISSECT_RET_IPPROTO_AGAIN:
1020                 if (skb_flow_dissect_allowed(&num_hdrs))
1021                         goto ip_proto_again;
1022                 break;
1023         case FLOW_DISSECT_RET_OUT_GOOD:
1024         case FLOW_DISSECT_RET_CONTINUE:
1025                 break;
1026         case FLOW_DISSECT_RET_OUT_BAD:
1027         default:
1028                 goto out_bad;
1029         }
1030
1031 out_good:
1032         ret = true;
1033
1034 out:
1035         key_control->thoff = min_t(u16, nhoff, skb ? skb->len : hlen);
1036         key_basic->n_proto = proto;
1037         key_basic->ip_proto = ip_proto;
1038
1039         return ret;
1040
1041 out_bad:
1042         ret = false;
1043         goto out;
1044 }
1045 EXPORT_SYMBOL(__skb_flow_dissect);
1046
1047 static u32 hashrnd __read_mostly;
1048 static __always_inline void __flow_hash_secret_init(void)
1049 {
1050         net_get_random_once(&hashrnd, sizeof(hashrnd));
1051 }
1052
1053 static __always_inline u32 __flow_hash_words(const u32 *words, u32 length,
1054                                              u32 keyval)
1055 {
1056         return jhash2(words, length, keyval);
1057 }
1058
1059 static inline const u32 *flow_keys_hash_start(const struct flow_keys *flow)
1060 {
1061         const void *p = flow;
1062
1063         BUILD_BUG_ON(FLOW_KEYS_HASH_OFFSET % sizeof(u32));
1064         return (const u32 *)(p + FLOW_KEYS_HASH_OFFSET);
1065 }
1066
1067 static inline size_t flow_keys_hash_length(const struct flow_keys *flow)
1068 {
1069         size_t diff = FLOW_KEYS_HASH_OFFSET + sizeof(flow->addrs);
1070         BUILD_BUG_ON((sizeof(*flow) - FLOW_KEYS_HASH_OFFSET) % sizeof(u32));
1071         BUILD_BUG_ON(offsetof(typeof(*flow), addrs) !=
1072                      sizeof(*flow) - sizeof(flow->addrs));
1073
1074         switch (flow->control.addr_type) {
1075         case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1076                 diff -= sizeof(flow->addrs.v4addrs);
1077                 break;
1078         case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1079                 diff -= sizeof(flow->addrs.v6addrs);
1080                 break;
1081         case FLOW_DISSECTOR_KEY_TIPC:
1082                 diff -= sizeof(flow->addrs.tipckey);
1083                 break;
1084         }
1085         return (sizeof(*flow) - diff) / sizeof(u32);
1086 }
1087
1088 __be32 flow_get_u32_src(const struct flow_keys *flow)
1089 {
1090         switch (flow->control.addr_type) {
1091         case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1092                 return flow->addrs.v4addrs.src;
1093         case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1094                 return (__force __be32)ipv6_addr_hash(
1095                         &flow->addrs.v6addrs.src);
1096         case FLOW_DISSECTOR_KEY_TIPC:
1097                 return flow->addrs.tipckey.key;
1098         default:
1099                 return 0;
1100         }
1101 }
1102 EXPORT_SYMBOL(flow_get_u32_src);
1103
1104 __be32 flow_get_u32_dst(const struct flow_keys *flow)
1105 {
1106         switch (flow->control.addr_type) {
1107         case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1108                 return flow->addrs.v4addrs.dst;
1109         case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1110                 return (__force __be32)ipv6_addr_hash(
1111                         &flow->addrs.v6addrs.dst);
1112         default:
1113                 return 0;
1114         }
1115 }
1116 EXPORT_SYMBOL(flow_get_u32_dst);
1117
1118 static inline void __flow_hash_consistentify(struct flow_keys *keys)
1119 {
1120         int addr_diff, i;
1121
1122         switch (keys->control.addr_type) {
1123         case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1124                 addr_diff = (__force u32)keys->addrs.v4addrs.dst -
1125                             (__force u32)keys->addrs.v4addrs.src;
1126                 if ((addr_diff < 0) ||
1127                     (addr_diff == 0 &&
1128                      ((__force u16)keys->ports.dst <
1129                       (__force u16)keys->ports.src))) {
1130                         swap(keys->addrs.v4addrs.src, keys->addrs.v4addrs.dst);
1131                         swap(keys->ports.src, keys->ports.dst);
1132                 }
1133                 break;
1134         case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1135                 addr_diff = memcmp(&keys->addrs.v6addrs.dst,
1136                                    &keys->addrs.v6addrs.src,
1137                                    sizeof(keys->addrs.v6addrs.dst));
1138                 if ((addr_diff < 0) ||
1139                     (addr_diff == 0 &&
1140                      ((__force u16)keys->ports.dst <
1141                       (__force u16)keys->ports.src))) {
1142                         for (i = 0; i < 4; i++)
1143                                 swap(keys->addrs.v6addrs.src.s6_addr32[i],
1144                                      keys->addrs.v6addrs.dst.s6_addr32[i]);
1145                         swap(keys->ports.src, keys->ports.dst);
1146                 }
1147                 break;
1148         }
1149 }
1150
1151 static inline u32 __flow_hash_from_keys(struct flow_keys *keys, u32 keyval)
1152 {
1153         u32 hash;
1154
1155         __flow_hash_consistentify(keys);
1156
1157         hash = __flow_hash_words(flow_keys_hash_start(keys),
1158                                  flow_keys_hash_length(keys), keyval);
1159         if (!hash)
1160                 hash = 1;
1161
1162         return hash;
1163 }
1164
1165 u32 flow_hash_from_keys(struct flow_keys *keys)
1166 {
1167         __flow_hash_secret_init();
1168         return __flow_hash_from_keys(keys, hashrnd);
1169 }
1170 EXPORT_SYMBOL(flow_hash_from_keys);
1171
1172 static inline u32 ___skb_get_hash(const struct sk_buff *skb,
1173                                   struct flow_keys *keys, u32 keyval)
1174 {
1175         skb_flow_dissect_flow_keys(skb, keys,
1176                                    FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
1177
1178         return __flow_hash_from_keys(keys, keyval);
1179 }
1180
1181 struct _flow_keys_digest_data {
1182         __be16  n_proto;
1183         u8      ip_proto;
1184         u8      padding;
1185         __be32  ports;
1186         __be32  src;
1187         __be32  dst;
1188 };
1189
1190 void make_flow_keys_digest(struct flow_keys_digest *digest,
1191                            const struct flow_keys *flow)
1192 {
1193         struct _flow_keys_digest_data *data =
1194             (struct _flow_keys_digest_data *)digest;
1195
1196         BUILD_BUG_ON(sizeof(*data) > sizeof(*digest));
1197
1198         memset(digest, 0, sizeof(*digest));
1199
1200         data->n_proto = flow->basic.n_proto;
1201         data->ip_proto = flow->basic.ip_proto;
1202         data->ports = flow->ports.ports;
1203         data->src = flow->addrs.v4addrs.src;
1204         data->dst = flow->addrs.v4addrs.dst;
1205 }
1206 EXPORT_SYMBOL(make_flow_keys_digest);
1207
1208 static struct flow_dissector flow_keys_dissector_symmetric __read_mostly;
1209
1210 u32 __skb_get_hash_symmetric(const struct sk_buff *skb)
1211 {
1212         struct flow_keys keys;
1213
1214         __flow_hash_secret_init();
1215
1216         memset(&keys, 0, sizeof(keys));
1217         __skb_flow_dissect(skb, &flow_keys_dissector_symmetric, &keys,
1218                            NULL, 0, 0, 0,
1219                            FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
1220
1221         return __flow_hash_from_keys(&keys, hashrnd);
1222 }
1223 EXPORT_SYMBOL_GPL(__skb_get_hash_symmetric);
1224
1225 /**
1226  * __skb_get_hash: calculate a flow hash
1227  * @skb: sk_buff to calculate flow hash from
1228  *
1229  * This function calculates a flow hash based on src/dst addresses
1230  * and src/dst port numbers.  Sets hash in skb to non-zero hash value
1231  * on success, zero indicates no valid hash.  Also, sets l4_hash in skb
1232  * if hash is a canonical 4-tuple hash over transport ports.
1233  */
1234 void __skb_get_hash(struct sk_buff *skb)
1235 {
1236         struct flow_keys keys;
1237         u32 hash;
1238
1239         __flow_hash_secret_init();
1240
1241         hash = ___skb_get_hash(skb, &keys, hashrnd);
1242
1243         __skb_set_sw_hash(skb, hash, flow_keys_have_l4(&keys));
1244 }
1245 EXPORT_SYMBOL(__skb_get_hash);
1246
1247 __u32 skb_get_hash_perturb(const struct sk_buff *skb, u32 perturb)
1248 {
1249         struct flow_keys keys;
1250
1251         return ___skb_get_hash(skb, &keys, perturb);
1252 }
1253 EXPORT_SYMBOL(skb_get_hash_perturb);
1254
1255 u32 __skb_get_poff(const struct sk_buff *skb, void *data,
1256                    const struct flow_keys *keys, int hlen)
1257 {
1258         u32 poff = keys->control.thoff;
1259
1260         /* skip L4 headers for fragments after the first */
1261         if ((keys->control.flags & FLOW_DIS_IS_FRAGMENT) &&
1262             !(keys->control.flags & FLOW_DIS_FIRST_FRAG))
1263                 return poff;
1264
1265         switch (keys->basic.ip_proto) {
1266         case IPPROTO_TCP: {
1267                 /* access doff as u8 to avoid unaligned access */
1268                 const u8 *doff;
1269                 u8 _doff;
1270
1271                 doff = __skb_header_pointer(skb, poff + 12, sizeof(_doff),
1272                                             data, hlen, &_doff);
1273                 if (!doff)
1274                         return poff;
1275
1276                 poff += max_t(u32, sizeof(struct tcphdr), (*doff & 0xF0) >> 2);
1277                 break;
1278         }
1279         case IPPROTO_UDP:
1280         case IPPROTO_UDPLITE:
1281                 poff += sizeof(struct udphdr);
1282                 break;
1283         /* For the rest, we do not really care about header
1284          * extensions at this point for now.
1285          */
1286         case IPPROTO_ICMP:
1287                 poff += sizeof(struct icmphdr);
1288                 break;
1289         case IPPROTO_ICMPV6:
1290                 poff += sizeof(struct icmp6hdr);
1291                 break;
1292         case IPPROTO_IGMP:
1293                 poff += sizeof(struct igmphdr);
1294                 break;
1295         case IPPROTO_DCCP:
1296                 poff += sizeof(struct dccp_hdr);
1297                 break;
1298         case IPPROTO_SCTP:
1299                 poff += sizeof(struct sctphdr);
1300                 break;
1301         }
1302
1303         return poff;
1304 }
1305
1306 /**
1307  * skb_get_poff - get the offset to the payload
1308  * @skb: sk_buff to get the payload offset from
1309  *
1310  * The function will get the offset to the payload as far as it could
1311  * be dissected.  The main user is currently BPF, so that we can dynamically
1312  * truncate packets without needing to push actual payload to the user
1313  * space and can analyze headers only, instead.
1314  */
1315 u32 skb_get_poff(const struct sk_buff *skb)
1316 {
1317         struct flow_keys keys;
1318
1319         if (!skb_flow_dissect_flow_keys(skb, &keys, 0))
1320                 return 0;
1321
1322         return __skb_get_poff(skb, skb->data, &keys, skb_headlen(skb));
1323 }
1324
1325 __u32 __get_hash_from_flowi6(const struct flowi6 *fl6, struct flow_keys *keys)
1326 {
1327         memset(keys, 0, sizeof(*keys));
1328
1329         memcpy(&keys->addrs.v6addrs.src, &fl6->saddr,
1330             sizeof(keys->addrs.v6addrs.src));
1331         memcpy(&keys->addrs.v6addrs.dst, &fl6->daddr,
1332             sizeof(keys->addrs.v6addrs.dst));
1333         keys->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
1334         keys->ports.src = fl6->fl6_sport;
1335         keys->ports.dst = fl6->fl6_dport;
1336         keys->keyid.keyid = fl6->fl6_gre_key;
1337         keys->tags.flow_label = (__force u32)fl6->flowlabel;
1338         keys->basic.ip_proto = fl6->flowi6_proto;
1339
1340         return flow_hash_from_keys(keys);
1341 }
1342 EXPORT_SYMBOL(__get_hash_from_flowi6);
1343
1344 static const struct flow_dissector_key flow_keys_dissector_keys[] = {
1345         {
1346                 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
1347                 .offset = offsetof(struct flow_keys, control),
1348         },
1349         {
1350                 .key_id = FLOW_DISSECTOR_KEY_BASIC,
1351                 .offset = offsetof(struct flow_keys, basic),
1352         },
1353         {
1354                 .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
1355                 .offset = offsetof(struct flow_keys, addrs.v4addrs),
1356         },
1357         {
1358                 .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
1359                 .offset = offsetof(struct flow_keys, addrs.v6addrs),
1360         },
1361         {
1362                 .key_id = FLOW_DISSECTOR_KEY_TIPC,
1363                 .offset = offsetof(struct flow_keys, addrs.tipckey),
1364         },
1365         {
1366                 .key_id = FLOW_DISSECTOR_KEY_PORTS,
1367                 .offset = offsetof(struct flow_keys, ports),
1368         },
1369         {
1370                 .key_id = FLOW_DISSECTOR_KEY_VLAN,
1371                 .offset = offsetof(struct flow_keys, vlan),
1372         },
1373         {
1374                 .key_id = FLOW_DISSECTOR_KEY_FLOW_LABEL,
1375                 .offset = offsetof(struct flow_keys, tags),
1376         },
1377         {
1378                 .key_id = FLOW_DISSECTOR_KEY_GRE_KEYID,
1379                 .offset = offsetof(struct flow_keys, keyid),
1380         },
1381 };
1382
1383 static const struct flow_dissector_key flow_keys_dissector_symmetric_keys[] = {
1384         {
1385                 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
1386                 .offset = offsetof(struct flow_keys, control),
1387         },
1388         {
1389                 .key_id = FLOW_DISSECTOR_KEY_BASIC,
1390                 .offset = offsetof(struct flow_keys, basic),
1391         },
1392         {
1393                 .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
1394                 .offset = offsetof(struct flow_keys, addrs.v4addrs),
1395         },
1396         {
1397                 .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
1398                 .offset = offsetof(struct flow_keys, addrs.v6addrs),
1399         },
1400         {
1401                 .key_id = FLOW_DISSECTOR_KEY_PORTS,
1402                 .offset = offsetof(struct flow_keys, ports),
1403         },
1404 };
1405
1406 static const struct flow_dissector_key flow_keys_buf_dissector_keys[] = {
1407         {
1408                 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
1409                 .offset = offsetof(struct flow_keys, control),
1410         },
1411         {
1412                 .key_id = FLOW_DISSECTOR_KEY_BASIC,
1413                 .offset = offsetof(struct flow_keys, basic),
1414         },
1415 };
1416
1417 struct flow_dissector flow_keys_dissector __read_mostly;
1418 EXPORT_SYMBOL(flow_keys_dissector);
1419
1420 struct flow_dissector flow_keys_buf_dissector __read_mostly;
1421
1422 static int __init init_default_flow_dissectors(void)
1423 {
1424         skb_flow_dissector_init(&flow_keys_dissector,
1425                                 flow_keys_dissector_keys,
1426                                 ARRAY_SIZE(flow_keys_dissector_keys));
1427         skb_flow_dissector_init(&flow_keys_dissector_symmetric,
1428                                 flow_keys_dissector_symmetric_keys,
1429                                 ARRAY_SIZE(flow_keys_dissector_symmetric_keys));
1430         skb_flow_dissector_init(&flow_keys_buf_dissector,
1431                                 flow_keys_buf_dissector_keys,
1432                                 ARRAY_SIZE(flow_keys_buf_dissector_keys));
1433         return 0;
1434 }
1435
1436 core_initcall(init_default_flow_dissectors);