1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/kernel.h>
3 #include <linux/skbuff.h>
4 #include <linux/export.h>
6 #include <linux/ipv6.h>
7 #include <linux/if_vlan.h>
9 #include <net/dst_metadata.h>
15 #include <linux/igmp.h>
16 #include <linux/icmp.h>
17 #include <linux/sctp.h>
18 #include <linux/dccp.h>
19 #include <linux/if_tunnel.h>
20 #include <linux/if_pppox.h>
21 #include <linux/ppp_defs.h>
22 #include <linux/stddef.h>
23 #include <linux/if_ether.h>
24 #include <linux/mpls.h>
25 #include <linux/tcp.h>
26 #include <linux/ptp_classify.h>
27 #include <net/flow_dissector.h>
28 #include <scsi/fc/fc_fcoe.h>
29 #include <uapi/linux/batadv_packet.h>
30 #include <linux/bpf.h>
31 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
32 #include <net/netfilter/nf_conntrack_core.h>
33 #include <net/netfilter/nf_conntrack_labels.h>
35 #include <linux/bpf-netns.h>
37 static void dissector_set_key(struct flow_dissector
*flow_dissector
,
38 enum flow_dissector_key_id key_id
)
40 flow_dissector
->used_keys
|= (1 << key_id
);
43 void skb_flow_dissector_init(struct flow_dissector
*flow_dissector
,
44 const struct flow_dissector_key
*key
,
45 unsigned int key_count
)
49 memset(flow_dissector
, 0, sizeof(*flow_dissector
));
51 for (i
= 0; i
< key_count
; i
++, key
++) {
52 /* User should make sure that every key target offset is within
53 * boundaries of unsigned short.
55 BUG_ON(key
->offset
> USHRT_MAX
);
56 BUG_ON(dissector_uses_key(flow_dissector
,
59 dissector_set_key(flow_dissector
, key
->key_id
);
60 flow_dissector
->offset
[key
->key_id
] = key
->offset
;
63 /* Ensure that the dissector always includes control and basic key.
64 * That way we are able to avoid handling lack of these in fast path.
66 BUG_ON(!dissector_uses_key(flow_dissector
,
67 FLOW_DISSECTOR_KEY_CONTROL
));
68 BUG_ON(!dissector_uses_key(flow_dissector
,
69 FLOW_DISSECTOR_KEY_BASIC
));
71 EXPORT_SYMBOL(skb_flow_dissector_init
);
73 #ifdef CONFIG_BPF_SYSCALL
74 int flow_dissector_bpf_prog_attach_check(struct net
*net
,
75 struct bpf_prog
*prog
)
77 enum netns_bpf_attach_type type
= NETNS_BPF_FLOW_DISSECTOR
;
79 if (net
== &init_net
) {
80 /* BPF flow dissector in the root namespace overrides
81 * any per-net-namespace one. When attaching to root,
82 * make sure we don't have any BPF program attached
83 * to the non-root namespaces.
90 if (rcu_access_pointer(ns
->bpf
.run_array
[type
]))
94 /* Make sure root flow dissector is not attached
95 * when attaching to the non-root namespace.
97 if (rcu_access_pointer(init_net
.bpf
.run_array
[type
]))
103 #endif /* CONFIG_BPF_SYSCALL */
106 * __skb_flow_get_ports - extract the upper layer ports and return them
107 * @skb: sk_buff to extract the ports from
108 * @thoff: transport header offset
109 * @ip_proto: protocol for which to get port offset
110 * @data: raw buffer pointer to the packet, if NULL use skb->data
111 * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
113 * The function will try to retrieve the ports at offset thoff + poff where poff
114 * is the protocol port offset returned from proto_ports_offset
116 __be32
__skb_flow_get_ports(const struct sk_buff
*skb
, int thoff
, u8 ip_proto
,
117 const void *data
, int hlen
)
119 int poff
= proto_ports_offset(ip_proto
);
123 hlen
= skb_headlen(skb
);
127 __be32
*ports
, _ports
;
129 ports
= __skb_header_pointer(skb
, thoff
+ poff
,
130 sizeof(_ports
), data
, hlen
, &_ports
);
137 EXPORT_SYMBOL(__skb_flow_get_ports
);
139 static bool icmp_has_id(u8 type
)
145 case ICMP_TIMESTAMPREPLY
:
146 case ICMPV6_ECHO_REQUEST
:
147 case ICMPV6_ECHO_REPLY
:
155 * skb_flow_get_icmp_tci - extract ICMP(6) Type, Code and Identifier fields
156 * @skb: sk_buff to extract from
157 * @key_icmp: struct flow_dissector_key_icmp to fill
158 * @data: raw buffer pointer to the packet
159 * @thoff: offset to extract at
160 * @hlen: packet header length
162 void skb_flow_get_icmp_tci(const struct sk_buff
*skb
,
163 struct flow_dissector_key_icmp
*key_icmp
,
164 const void *data
, int thoff
, int hlen
)
166 struct icmphdr
*ih
, _ih
;
168 ih
= __skb_header_pointer(skb
, thoff
, sizeof(_ih
), data
, hlen
, &_ih
);
172 key_icmp
->type
= ih
->type
;
173 key_icmp
->code
= ih
->code
;
175 /* As we use 0 to signal that the Id field is not present,
176 * avoid confusion with packets without such field
178 if (icmp_has_id(ih
->type
))
179 key_icmp
->id
= ih
->un
.echo
.id
? ntohs(ih
->un
.echo
.id
) : 1;
183 EXPORT_SYMBOL(skb_flow_get_icmp_tci
);
185 /* If FLOW_DISSECTOR_KEY_ICMP is set, dissect an ICMP packet
186 * using skb_flow_get_icmp_tci().
188 static void __skb_flow_dissect_icmp(const struct sk_buff
*skb
,
189 struct flow_dissector
*flow_dissector
,
190 void *target_container
, const void *data
,
193 struct flow_dissector_key_icmp
*key_icmp
;
195 if (!dissector_uses_key(flow_dissector
, FLOW_DISSECTOR_KEY_ICMP
))
198 key_icmp
= skb_flow_dissector_target(flow_dissector
,
199 FLOW_DISSECTOR_KEY_ICMP
,
202 skb_flow_get_icmp_tci(skb
, key_icmp
, data
, thoff
, hlen
);
205 void skb_flow_dissect_meta(const struct sk_buff
*skb
,
206 struct flow_dissector
*flow_dissector
,
207 void *target_container
)
209 struct flow_dissector_key_meta
*meta
;
211 if (!dissector_uses_key(flow_dissector
, FLOW_DISSECTOR_KEY_META
))
214 meta
= skb_flow_dissector_target(flow_dissector
,
215 FLOW_DISSECTOR_KEY_META
,
217 meta
->ingress_ifindex
= skb
->skb_iif
;
219 EXPORT_SYMBOL(skb_flow_dissect_meta
);
222 skb_flow_dissect_set_enc_addr_type(enum flow_dissector_key_id type
,
223 struct flow_dissector
*flow_dissector
,
224 void *target_container
)
226 struct flow_dissector_key_control
*ctrl
;
228 if (!dissector_uses_key(flow_dissector
, FLOW_DISSECTOR_KEY_ENC_CONTROL
))
231 ctrl
= skb_flow_dissector_target(flow_dissector
,
232 FLOW_DISSECTOR_KEY_ENC_CONTROL
,
234 ctrl
->addr_type
= type
;
238 skb_flow_dissect_ct(const struct sk_buff
*skb
,
239 struct flow_dissector
*flow_dissector
,
240 void *target_container
, u16
*ctinfo_map
,
241 size_t mapsize
, bool post_ct
)
243 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
244 struct flow_dissector_key_ct
*key
;
245 enum ip_conntrack_info ctinfo
;
246 struct nf_conn_labels
*cl
;
249 if (!dissector_uses_key(flow_dissector
, FLOW_DISSECTOR_KEY_CT
))
252 ct
= nf_ct_get(skb
, &ctinfo
);
256 key
= skb_flow_dissector_target(flow_dissector
,
257 FLOW_DISSECTOR_KEY_CT
,
261 key
->ct_state
= TCA_FLOWER_KEY_CT_FLAGS_TRACKED
|
262 TCA_FLOWER_KEY_CT_FLAGS_INVALID
;
266 if (ctinfo
< mapsize
)
267 key
->ct_state
= ctinfo_map
[ctinfo
];
268 #if IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)
269 key
->ct_zone
= ct
->zone
.id
;
271 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
272 key
->ct_mark
= ct
->mark
;
275 cl
= nf_ct_labels_find(ct
);
277 memcpy(key
->ct_labels
, cl
->bits
, sizeof(key
->ct_labels
));
278 #endif /* CONFIG_NF_CONNTRACK */
280 EXPORT_SYMBOL(skb_flow_dissect_ct
);
283 skb_flow_dissect_tunnel_info(const struct sk_buff
*skb
,
284 struct flow_dissector
*flow_dissector
,
285 void *target_container
)
287 struct ip_tunnel_info
*info
;
288 struct ip_tunnel_key
*key
;
290 /* A quick check to see if there might be something to do. */
291 if (!dissector_uses_key(flow_dissector
,
292 FLOW_DISSECTOR_KEY_ENC_KEYID
) &&
293 !dissector_uses_key(flow_dissector
,
294 FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS
) &&
295 !dissector_uses_key(flow_dissector
,
296 FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS
) &&
297 !dissector_uses_key(flow_dissector
,
298 FLOW_DISSECTOR_KEY_ENC_CONTROL
) &&
299 !dissector_uses_key(flow_dissector
,
300 FLOW_DISSECTOR_KEY_ENC_PORTS
) &&
301 !dissector_uses_key(flow_dissector
,
302 FLOW_DISSECTOR_KEY_ENC_IP
) &&
303 !dissector_uses_key(flow_dissector
,
304 FLOW_DISSECTOR_KEY_ENC_OPTS
))
307 info
= skb_tunnel_info(skb
);
313 switch (ip_tunnel_info_af(info
)) {
315 skb_flow_dissect_set_enc_addr_type(FLOW_DISSECTOR_KEY_IPV4_ADDRS
,
318 if (dissector_uses_key(flow_dissector
,
319 FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS
)) {
320 struct flow_dissector_key_ipv4_addrs
*ipv4
;
322 ipv4
= skb_flow_dissector_target(flow_dissector
,
323 FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS
,
325 ipv4
->src
= key
->u
.ipv4
.src
;
326 ipv4
->dst
= key
->u
.ipv4
.dst
;
330 skb_flow_dissect_set_enc_addr_type(FLOW_DISSECTOR_KEY_IPV6_ADDRS
,
333 if (dissector_uses_key(flow_dissector
,
334 FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS
)) {
335 struct flow_dissector_key_ipv6_addrs
*ipv6
;
337 ipv6
= skb_flow_dissector_target(flow_dissector
,
338 FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS
,
340 ipv6
->src
= key
->u
.ipv6
.src
;
341 ipv6
->dst
= key
->u
.ipv6
.dst
;
346 if (dissector_uses_key(flow_dissector
, FLOW_DISSECTOR_KEY_ENC_KEYID
)) {
347 struct flow_dissector_key_keyid
*keyid
;
349 keyid
= skb_flow_dissector_target(flow_dissector
,
350 FLOW_DISSECTOR_KEY_ENC_KEYID
,
352 keyid
->keyid
= tunnel_id_to_key32(key
->tun_id
);
355 if (dissector_uses_key(flow_dissector
, FLOW_DISSECTOR_KEY_ENC_PORTS
)) {
356 struct flow_dissector_key_ports
*tp
;
358 tp
= skb_flow_dissector_target(flow_dissector
,
359 FLOW_DISSECTOR_KEY_ENC_PORTS
,
361 tp
->src
= key
->tp_src
;
362 tp
->dst
= key
->tp_dst
;
365 if (dissector_uses_key(flow_dissector
, FLOW_DISSECTOR_KEY_ENC_IP
)) {
366 struct flow_dissector_key_ip
*ip
;
368 ip
= skb_flow_dissector_target(flow_dissector
,
369 FLOW_DISSECTOR_KEY_ENC_IP
,
375 if (dissector_uses_key(flow_dissector
, FLOW_DISSECTOR_KEY_ENC_OPTS
)) {
376 struct flow_dissector_key_enc_opts
*enc_opt
;
378 enc_opt
= skb_flow_dissector_target(flow_dissector
,
379 FLOW_DISSECTOR_KEY_ENC_OPTS
,
382 if (info
->options_len
) {
383 enc_opt
->len
= info
->options_len
;
384 ip_tunnel_info_opts_get(enc_opt
->data
, info
);
385 enc_opt
->dst_opt_type
= info
->key
.tun_flags
&
386 TUNNEL_OPTIONS_PRESENT
;
390 EXPORT_SYMBOL(skb_flow_dissect_tunnel_info
);
392 void skb_flow_dissect_hash(const struct sk_buff
*skb
,
393 struct flow_dissector
*flow_dissector
,
394 void *target_container
)
396 struct flow_dissector_key_hash
*key
;
398 if (!dissector_uses_key(flow_dissector
, FLOW_DISSECTOR_KEY_HASH
))
401 key
= skb_flow_dissector_target(flow_dissector
,
402 FLOW_DISSECTOR_KEY_HASH
,
405 key
->hash
= skb_get_hash_raw(skb
);
407 EXPORT_SYMBOL(skb_flow_dissect_hash
);
409 static enum flow_dissect_ret
410 __skb_flow_dissect_mpls(const struct sk_buff
*skb
,
411 struct flow_dissector
*flow_dissector
,
412 void *target_container
, const void *data
, int nhoff
,
413 int hlen
, int lse_index
, bool *entropy_label
)
415 struct mpls_label
*hdr
, _hdr
;
416 u32 entry
, label
, bos
;
418 if (!dissector_uses_key(flow_dissector
,
419 FLOW_DISSECTOR_KEY_MPLS_ENTROPY
) &&
420 !dissector_uses_key(flow_dissector
, FLOW_DISSECTOR_KEY_MPLS
))
421 return FLOW_DISSECT_RET_OUT_GOOD
;
423 if (lse_index
>= FLOW_DIS_MPLS_MAX
)
424 return FLOW_DISSECT_RET_OUT_GOOD
;
426 hdr
= __skb_header_pointer(skb
, nhoff
, sizeof(_hdr
), data
,
429 return FLOW_DISSECT_RET_OUT_BAD
;
431 entry
= ntohl(hdr
->entry
);
432 label
= (entry
& MPLS_LS_LABEL_MASK
) >> MPLS_LS_LABEL_SHIFT
;
433 bos
= (entry
& MPLS_LS_S_MASK
) >> MPLS_LS_S_SHIFT
;
435 if (dissector_uses_key(flow_dissector
, FLOW_DISSECTOR_KEY_MPLS
)) {
436 struct flow_dissector_key_mpls
*key_mpls
;
437 struct flow_dissector_mpls_lse
*lse
;
439 key_mpls
= skb_flow_dissector_target(flow_dissector
,
440 FLOW_DISSECTOR_KEY_MPLS
,
442 lse
= &key_mpls
->ls
[lse_index
];
444 lse
->mpls_ttl
= (entry
& MPLS_LS_TTL_MASK
) >> MPLS_LS_TTL_SHIFT
;
446 lse
->mpls_tc
= (entry
& MPLS_LS_TC_MASK
) >> MPLS_LS_TC_SHIFT
;
447 lse
->mpls_label
= label
;
448 dissector_set_mpls_lse(key_mpls
, lse_index
);
451 if (*entropy_label
&&
452 dissector_uses_key(flow_dissector
,
453 FLOW_DISSECTOR_KEY_MPLS_ENTROPY
)) {
454 struct flow_dissector_key_keyid
*key_keyid
;
456 key_keyid
= skb_flow_dissector_target(flow_dissector
,
457 FLOW_DISSECTOR_KEY_MPLS_ENTROPY
,
459 key_keyid
->keyid
= cpu_to_be32(label
);
462 *entropy_label
= label
== MPLS_LABEL_ENTROPY
;
464 return bos
? FLOW_DISSECT_RET_OUT_GOOD
: FLOW_DISSECT_RET_PROTO_AGAIN
;
467 static enum flow_dissect_ret
468 __skb_flow_dissect_arp(const struct sk_buff
*skb
,
469 struct flow_dissector
*flow_dissector
,
470 void *target_container
, const void *data
,
473 struct flow_dissector_key_arp
*key_arp
;
475 unsigned char ar_sha
[ETH_ALEN
];
476 unsigned char ar_sip
[4];
477 unsigned char ar_tha
[ETH_ALEN
];
478 unsigned char ar_tip
[4];
479 } *arp_eth
, _arp_eth
;
480 const struct arphdr
*arp
;
483 if (!dissector_uses_key(flow_dissector
, FLOW_DISSECTOR_KEY_ARP
))
484 return FLOW_DISSECT_RET_OUT_GOOD
;
486 arp
= __skb_header_pointer(skb
, nhoff
, sizeof(_arp
), data
,
489 return FLOW_DISSECT_RET_OUT_BAD
;
491 if (arp
->ar_hrd
!= htons(ARPHRD_ETHER
) ||
492 arp
->ar_pro
!= htons(ETH_P_IP
) ||
493 arp
->ar_hln
!= ETH_ALEN
||
495 (arp
->ar_op
!= htons(ARPOP_REPLY
) &&
496 arp
->ar_op
!= htons(ARPOP_REQUEST
)))
497 return FLOW_DISSECT_RET_OUT_BAD
;
499 arp_eth
= __skb_header_pointer(skb
, nhoff
+ sizeof(_arp
),
500 sizeof(_arp_eth
), data
,
503 return FLOW_DISSECT_RET_OUT_BAD
;
505 key_arp
= skb_flow_dissector_target(flow_dissector
,
506 FLOW_DISSECTOR_KEY_ARP
,
509 memcpy(&key_arp
->sip
, arp_eth
->ar_sip
, sizeof(key_arp
->sip
));
510 memcpy(&key_arp
->tip
, arp_eth
->ar_tip
, sizeof(key_arp
->tip
));
512 /* Only store the lower byte of the opcode;
513 * this covers ARPOP_REPLY and ARPOP_REQUEST.
515 key_arp
->op
= ntohs(arp
->ar_op
) & 0xff;
517 ether_addr_copy(key_arp
->sha
, arp_eth
->ar_sha
);
518 ether_addr_copy(key_arp
->tha
, arp_eth
->ar_tha
);
520 return FLOW_DISSECT_RET_OUT_GOOD
;
523 static enum flow_dissect_ret
524 __skb_flow_dissect_gre(const struct sk_buff
*skb
,
525 struct flow_dissector_key_control
*key_control
,
526 struct flow_dissector
*flow_dissector
,
527 void *target_container
, const void *data
,
528 __be16
*p_proto
, int *p_nhoff
, int *p_hlen
,
531 struct flow_dissector_key_keyid
*key_keyid
;
532 struct gre_base_hdr
*hdr
, _hdr
;
536 hdr
= __skb_header_pointer(skb
, *p_nhoff
, sizeof(_hdr
),
537 data
, *p_hlen
, &_hdr
);
539 return FLOW_DISSECT_RET_OUT_BAD
;
541 /* Only look inside GRE without routing */
542 if (hdr
->flags
& GRE_ROUTING
)
543 return FLOW_DISSECT_RET_OUT_GOOD
;
545 /* Only look inside GRE for version 0 and 1 */
546 gre_ver
= ntohs(hdr
->flags
& GRE_VERSION
);
548 return FLOW_DISSECT_RET_OUT_GOOD
;
550 *p_proto
= hdr
->protocol
;
552 /* Version1 must be PPTP, and check the flags */
553 if (!(*p_proto
== GRE_PROTO_PPP
&& (hdr
->flags
& GRE_KEY
)))
554 return FLOW_DISSECT_RET_OUT_GOOD
;
557 offset
+= sizeof(struct gre_base_hdr
);
559 if (hdr
->flags
& GRE_CSUM
)
560 offset
+= sizeof_field(struct gre_full_hdr
, csum
) +
561 sizeof_field(struct gre_full_hdr
, reserved1
);
563 if (hdr
->flags
& GRE_KEY
) {
567 keyid
= __skb_header_pointer(skb
, *p_nhoff
+ offset
,
569 data
, *p_hlen
, &_keyid
);
571 return FLOW_DISSECT_RET_OUT_BAD
;
573 if (dissector_uses_key(flow_dissector
,
574 FLOW_DISSECTOR_KEY_GRE_KEYID
)) {
575 key_keyid
= skb_flow_dissector_target(flow_dissector
,
576 FLOW_DISSECTOR_KEY_GRE_KEYID
,
579 key_keyid
->keyid
= *keyid
;
581 key_keyid
->keyid
= *keyid
& GRE_PPTP_KEY_MASK
;
583 offset
+= sizeof_field(struct gre_full_hdr
, key
);
586 if (hdr
->flags
& GRE_SEQ
)
587 offset
+= sizeof_field(struct pptp_gre_header
, seq
);
590 if (*p_proto
== htons(ETH_P_TEB
)) {
591 const struct ethhdr
*eth
;
594 eth
= __skb_header_pointer(skb
, *p_nhoff
+ offset
,
596 data
, *p_hlen
, &_eth
);
598 return FLOW_DISSECT_RET_OUT_BAD
;
599 *p_proto
= eth
->h_proto
;
600 offset
+= sizeof(*eth
);
602 /* Cap headers that we access via pointers at the
603 * end of the Ethernet header as our maximum alignment
604 * at that point is only 2 bytes.
607 *p_hlen
= *p_nhoff
+ offset
;
609 } else { /* version 1, must be PPTP */
610 u8 _ppp_hdr
[PPP_HDRLEN
];
613 if (hdr
->flags
& GRE_ACK
)
614 offset
+= sizeof_field(struct pptp_gre_header
, ack
);
616 ppp_hdr
= __skb_header_pointer(skb
, *p_nhoff
+ offset
,
618 data
, *p_hlen
, _ppp_hdr
);
620 return FLOW_DISSECT_RET_OUT_BAD
;
622 switch (PPP_PROTOCOL(ppp_hdr
)) {
624 *p_proto
= htons(ETH_P_IP
);
627 *p_proto
= htons(ETH_P_IPV6
);
630 /* Could probably catch some more like MPLS */
634 offset
+= PPP_HDRLEN
;
638 key_control
->flags
|= FLOW_DIS_ENCAPSULATION
;
639 if (flags
& FLOW_DISSECTOR_F_STOP_AT_ENCAP
)
640 return FLOW_DISSECT_RET_OUT_GOOD
;
642 return FLOW_DISSECT_RET_PROTO_AGAIN
;
646 * __skb_flow_dissect_batadv() - dissect batman-adv header
647 * @skb: sk_buff to with the batman-adv header
648 * @key_control: flow dissectors control key
649 * @data: raw buffer pointer to the packet, if NULL use skb->data
650 * @p_proto: pointer used to update the protocol to process next
651 * @p_nhoff: pointer used to update inner network header offset
652 * @hlen: packet header length
653 * @flags: any combination of FLOW_DISSECTOR_F_*
655 * ETH_P_BATMAN packets are tried to be dissected. Only
656 * &struct batadv_unicast packets are actually processed because they contain an
657 * inner ethernet header and are usually followed by actual network header. This
658 * allows the flow dissector to continue processing the packet.
660 * Return: FLOW_DISSECT_RET_PROTO_AGAIN when &struct batadv_unicast was found,
661 * FLOW_DISSECT_RET_OUT_GOOD when dissector should stop after encapsulation,
662 * otherwise FLOW_DISSECT_RET_OUT_BAD
664 static enum flow_dissect_ret
665 __skb_flow_dissect_batadv(const struct sk_buff
*skb
,
666 struct flow_dissector_key_control
*key_control
,
667 const void *data
, __be16
*p_proto
, int *p_nhoff
,
668 int hlen
, unsigned int flags
)
671 struct batadv_unicast_packet batadv_unicast
;
675 hdr
= __skb_header_pointer(skb
, *p_nhoff
, sizeof(_hdr
), data
, hlen
,
678 return FLOW_DISSECT_RET_OUT_BAD
;
680 if (hdr
->batadv_unicast
.version
!= BATADV_COMPAT_VERSION
)
681 return FLOW_DISSECT_RET_OUT_BAD
;
683 if (hdr
->batadv_unicast
.packet_type
!= BATADV_UNICAST
)
684 return FLOW_DISSECT_RET_OUT_BAD
;
686 *p_proto
= hdr
->eth
.h_proto
;
687 *p_nhoff
+= sizeof(*hdr
);
689 key_control
->flags
|= FLOW_DIS_ENCAPSULATION
;
690 if (flags
& FLOW_DISSECTOR_F_STOP_AT_ENCAP
)
691 return FLOW_DISSECT_RET_OUT_GOOD
;
693 return FLOW_DISSECT_RET_PROTO_AGAIN
;
697 __skb_flow_dissect_tcp(const struct sk_buff
*skb
,
698 struct flow_dissector
*flow_dissector
,
699 void *target_container
, const void *data
,
702 struct flow_dissector_key_tcp
*key_tcp
;
703 struct tcphdr
*th
, _th
;
705 if (!dissector_uses_key(flow_dissector
, FLOW_DISSECTOR_KEY_TCP
))
708 th
= __skb_header_pointer(skb
, thoff
, sizeof(_th
), data
, hlen
, &_th
);
712 if (unlikely(__tcp_hdrlen(th
) < sizeof(_th
)))
715 key_tcp
= skb_flow_dissector_target(flow_dissector
,
716 FLOW_DISSECTOR_KEY_TCP
,
718 key_tcp
->flags
= (*(__be16
*) &tcp_flag_word(th
) & htons(0x0FFF));
722 __skb_flow_dissect_ports(const struct sk_buff
*skb
,
723 struct flow_dissector
*flow_dissector
,
724 void *target_container
, const void *data
,
725 int nhoff
, u8 ip_proto
, int hlen
)
727 enum flow_dissector_key_id dissector_ports
= FLOW_DISSECTOR_KEY_MAX
;
728 struct flow_dissector_key_ports
*key_ports
;
730 if (dissector_uses_key(flow_dissector
, FLOW_DISSECTOR_KEY_PORTS
))
731 dissector_ports
= FLOW_DISSECTOR_KEY_PORTS
;
732 else if (dissector_uses_key(flow_dissector
,
733 FLOW_DISSECTOR_KEY_PORTS_RANGE
))
734 dissector_ports
= FLOW_DISSECTOR_KEY_PORTS_RANGE
;
736 if (dissector_ports
== FLOW_DISSECTOR_KEY_MAX
)
739 key_ports
= skb_flow_dissector_target(flow_dissector
,
742 key_ports
->ports
= __skb_flow_get_ports(skb
, nhoff
, ip_proto
,
747 __skb_flow_dissect_ipv4(const struct sk_buff
*skb
,
748 struct flow_dissector
*flow_dissector
,
749 void *target_container
, const void *data
,
750 const struct iphdr
*iph
)
752 struct flow_dissector_key_ip
*key_ip
;
754 if (!dissector_uses_key(flow_dissector
, FLOW_DISSECTOR_KEY_IP
))
757 key_ip
= skb_flow_dissector_target(flow_dissector
,
758 FLOW_DISSECTOR_KEY_IP
,
760 key_ip
->tos
= iph
->tos
;
761 key_ip
->ttl
= iph
->ttl
;
765 __skb_flow_dissect_ipv6(const struct sk_buff
*skb
,
766 struct flow_dissector
*flow_dissector
,
767 void *target_container
, const void *data
,
768 const struct ipv6hdr
*iph
)
770 struct flow_dissector_key_ip
*key_ip
;
772 if (!dissector_uses_key(flow_dissector
, FLOW_DISSECTOR_KEY_IP
))
775 key_ip
= skb_flow_dissector_target(flow_dissector
,
776 FLOW_DISSECTOR_KEY_IP
,
778 key_ip
->tos
= ipv6_get_dsfield(iph
);
779 key_ip
->ttl
= iph
->hop_limit
;
782 /* Maximum number of protocol headers that can be parsed in
785 #define MAX_FLOW_DISSECT_HDRS 15
787 static bool skb_flow_dissect_allowed(int *num_hdrs
)
791 return (*num_hdrs
<= MAX_FLOW_DISSECT_HDRS
);
794 static void __skb_flow_bpf_to_target(const struct bpf_flow_keys
*flow_keys
,
795 struct flow_dissector
*flow_dissector
,
796 void *target_container
)
798 struct flow_dissector_key_ports
*key_ports
= NULL
;
799 struct flow_dissector_key_control
*key_control
;
800 struct flow_dissector_key_basic
*key_basic
;
801 struct flow_dissector_key_addrs
*key_addrs
;
802 struct flow_dissector_key_tags
*key_tags
;
804 key_control
= skb_flow_dissector_target(flow_dissector
,
805 FLOW_DISSECTOR_KEY_CONTROL
,
807 key_control
->thoff
= flow_keys
->thoff
;
808 if (flow_keys
->is_frag
)
809 key_control
->flags
|= FLOW_DIS_IS_FRAGMENT
;
810 if (flow_keys
->is_first_frag
)
811 key_control
->flags
|= FLOW_DIS_FIRST_FRAG
;
812 if (flow_keys
->is_encap
)
813 key_control
->flags
|= FLOW_DIS_ENCAPSULATION
;
815 key_basic
= skb_flow_dissector_target(flow_dissector
,
816 FLOW_DISSECTOR_KEY_BASIC
,
818 key_basic
->n_proto
= flow_keys
->n_proto
;
819 key_basic
->ip_proto
= flow_keys
->ip_proto
;
821 if (flow_keys
->addr_proto
== ETH_P_IP
&&
822 dissector_uses_key(flow_dissector
, FLOW_DISSECTOR_KEY_IPV4_ADDRS
)) {
823 key_addrs
= skb_flow_dissector_target(flow_dissector
,
824 FLOW_DISSECTOR_KEY_IPV4_ADDRS
,
826 key_addrs
->v4addrs
.src
= flow_keys
->ipv4_src
;
827 key_addrs
->v4addrs
.dst
= flow_keys
->ipv4_dst
;
828 key_control
->addr_type
= FLOW_DISSECTOR_KEY_IPV4_ADDRS
;
829 } else if (flow_keys
->addr_proto
== ETH_P_IPV6
&&
830 dissector_uses_key(flow_dissector
,
831 FLOW_DISSECTOR_KEY_IPV6_ADDRS
)) {
832 key_addrs
= skb_flow_dissector_target(flow_dissector
,
833 FLOW_DISSECTOR_KEY_IPV6_ADDRS
,
835 memcpy(&key_addrs
->v6addrs
.src
, &flow_keys
->ipv6_src
,
836 sizeof(key_addrs
->v6addrs
.src
));
837 memcpy(&key_addrs
->v6addrs
.dst
, &flow_keys
->ipv6_dst
,
838 sizeof(key_addrs
->v6addrs
.dst
));
839 key_control
->addr_type
= FLOW_DISSECTOR_KEY_IPV6_ADDRS
;
842 if (dissector_uses_key(flow_dissector
, FLOW_DISSECTOR_KEY_PORTS
))
843 key_ports
= skb_flow_dissector_target(flow_dissector
,
844 FLOW_DISSECTOR_KEY_PORTS
,
846 else if (dissector_uses_key(flow_dissector
,
847 FLOW_DISSECTOR_KEY_PORTS_RANGE
))
848 key_ports
= skb_flow_dissector_target(flow_dissector
,
849 FLOW_DISSECTOR_KEY_PORTS_RANGE
,
853 key_ports
->src
= flow_keys
->sport
;
854 key_ports
->dst
= flow_keys
->dport
;
857 if (dissector_uses_key(flow_dissector
,
858 FLOW_DISSECTOR_KEY_FLOW_LABEL
)) {
859 key_tags
= skb_flow_dissector_target(flow_dissector
,
860 FLOW_DISSECTOR_KEY_FLOW_LABEL
,
862 key_tags
->flow_label
= ntohl(flow_keys
->flow_label
);
866 bool bpf_flow_dissect(struct bpf_prog
*prog
, struct bpf_flow_dissector
*ctx
,
867 __be16 proto
, int nhoff
, int hlen
, unsigned int flags
)
869 struct bpf_flow_keys
*flow_keys
= ctx
->flow_keys
;
872 /* Pass parameters to the BPF program */
873 memset(flow_keys
, 0, sizeof(*flow_keys
));
874 flow_keys
->n_proto
= proto
;
875 flow_keys
->nhoff
= nhoff
;
876 flow_keys
->thoff
= flow_keys
->nhoff
;
878 BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_PARSE_1ST_FRAG
!=
879 (int)FLOW_DISSECTOR_F_PARSE_1ST_FRAG
);
880 BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL
!=
881 (int)FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL
);
882 BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_STOP_AT_ENCAP
!=
883 (int)FLOW_DISSECTOR_F_STOP_AT_ENCAP
);
884 flow_keys
->flags
= flags
;
886 result
= bpf_prog_run_pin_on_cpu(prog
, ctx
);
888 flow_keys
->nhoff
= clamp_t(u16
, flow_keys
->nhoff
, nhoff
, hlen
);
889 flow_keys
->thoff
= clamp_t(u16
, flow_keys
->thoff
,
890 flow_keys
->nhoff
, hlen
);
892 return result
== BPF_OK
;
896 * __skb_flow_dissect - extract the flow_keys struct and return it
897 * @net: associated network namespace, derived from @skb if NULL
898 * @skb: sk_buff to extract the flow from, can be NULL if the rest are specified
899 * @flow_dissector: list of keys to dissect
900 * @target_container: target structure to put dissected values into
901 * @data: raw buffer pointer to the packet, if NULL use skb->data
902 * @proto: protocol for which to get the flow, if @data is NULL use skb->protocol
903 * @nhoff: network header offset, if @data is NULL use skb_network_offset(skb)
904 * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
905 * @flags: flags that control the dissection process, e.g.
906 * FLOW_DISSECTOR_F_STOP_AT_ENCAP.
908 * The function will try to retrieve individual keys into target specified
909 * by flow_dissector from either the skbuff or a raw buffer specified by the
912 * Caller must take care of zeroing target container memory.
914 bool __skb_flow_dissect(const struct net
*net
,
915 const struct sk_buff
*skb
,
916 struct flow_dissector
*flow_dissector
,
917 void *target_container
, const void *data
,
918 __be16 proto
, int nhoff
, int hlen
, unsigned int flags
)
920 struct flow_dissector_key_control
*key_control
;
921 struct flow_dissector_key_basic
*key_basic
;
922 struct flow_dissector_key_addrs
*key_addrs
;
923 struct flow_dissector_key_tags
*key_tags
;
924 struct flow_dissector_key_vlan
*key_vlan
;
925 enum flow_dissect_ret fdret
;
926 enum flow_dissector_key_id dissector_vlan
= FLOW_DISSECTOR_KEY_MAX
;
927 bool mpls_el
= false;
935 proto
= skb_vlan_tag_present(skb
) ?
936 skb
->vlan_proto
: skb
->protocol
;
937 nhoff
= skb_network_offset(skb
);
938 hlen
= skb_headlen(skb
);
939 #if IS_ENABLED(CONFIG_NET_DSA)
940 if (unlikely(skb
->dev
&& netdev_uses_dsa(skb
->dev
) &&
941 proto
== htons(ETH_P_XDSA
))) {
942 const struct dsa_device_ops
*ops
;
945 ops
= skb
->dev
->dsa_ptr
->tag_ops
;
946 /* Only DSA header taggers break flow dissection */
947 if (ops
->needed_headroom
) {
948 if (ops
->flow_dissect
)
949 ops
->flow_dissect(skb
, &proto
, &offset
);
951 dsa_tag_generic_flow_dissect(skb
,
961 /* It is ensured by skb_flow_dissector_init() that control key will
964 key_control
= skb_flow_dissector_target(flow_dissector
,
965 FLOW_DISSECTOR_KEY_CONTROL
,
968 /* It is ensured by skb_flow_dissector_init() that basic key will
971 key_basic
= skb_flow_dissector_target(flow_dissector
,
972 FLOW_DISSECTOR_KEY_BASIC
,
978 net
= dev_net(skb
->dev
);
980 net
= sock_net(skb
->sk
);
986 enum netns_bpf_attach_type type
= NETNS_BPF_FLOW_DISSECTOR
;
987 struct bpf_prog_array
*run_array
;
990 run_array
= rcu_dereference(init_net
.bpf
.run_array
[type
]);
992 run_array
= rcu_dereference(net
->bpf
.run_array
[type
]);
995 struct bpf_flow_keys flow_keys
;
996 struct bpf_flow_dissector ctx
= {
997 .flow_keys
= &flow_keys
,
999 .data_end
= data
+ hlen
,
1001 __be16 n_proto
= proto
;
1002 struct bpf_prog
*prog
;
1006 /* we can't use 'proto' in the skb case
1007 * because it might be set to skb->vlan_proto
1008 * which has been pulled from the data
1010 n_proto
= skb
->protocol
;
1013 prog
= READ_ONCE(run_array
->items
[0].prog
);
1014 ret
= bpf_flow_dissect(prog
, &ctx
, n_proto
, nhoff
,
1016 __skb_flow_bpf_to_target(&flow_keys
, flow_dissector
,
1024 if (dissector_uses_key(flow_dissector
,
1025 FLOW_DISSECTOR_KEY_ETH_ADDRS
)) {
1026 struct ethhdr
*eth
= eth_hdr(skb
);
1027 struct flow_dissector_key_eth_addrs
*key_eth_addrs
;
1029 key_eth_addrs
= skb_flow_dissector_target(flow_dissector
,
1030 FLOW_DISSECTOR_KEY_ETH_ADDRS
,
1032 memcpy(key_eth_addrs
, ð
->h_dest
, sizeof(*key_eth_addrs
));
1036 fdret
= FLOW_DISSECT_RET_CONTINUE
;
1039 case htons(ETH_P_IP
): {
1040 const struct iphdr
*iph
;
1043 iph
= __skb_header_pointer(skb
, nhoff
, sizeof(_iph
), data
, hlen
, &_iph
);
1044 if (!iph
|| iph
->ihl
< 5) {
1045 fdret
= FLOW_DISSECT_RET_OUT_BAD
;
1049 nhoff
+= iph
->ihl
* 4;
1051 ip_proto
= iph
->protocol
;
1053 if (dissector_uses_key(flow_dissector
,
1054 FLOW_DISSECTOR_KEY_IPV4_ADDRS
)) {
1055 key_addrs
= skb_flow_dissector_target(flow_dissector
,
1056 FLOW_DISSECTOR_KEY_IPV4_ADDRS
,
1059 memcpy(&key_addrs
->v4addrs
.src
, &iph
->saddr
,
1060 sizeof(key_addrs
->v4addrs
.src
));
1061 memcpy(&key_addrs
->v4addrs
.dst
, &iph
->daddr
,
1062 sizeof(key_addrs
->v4addrs
.dst
));
1063 key_control
->addr_type
= FLOW_DISSECTOR_KEY_IPV4_ADDRS
;
1066 __skb_flow_dissect_ipv4(skb
, flow_dissector
,
1067 target_container
, data
, iph
);
1069 if (ip_is_fragment(iph
)) {
1070 key_control
->flags
|= FLOW_DIS_IS_FRAGMENT
;
1072 if (iph
->frag_off
& htons(IP_OFFSET
)) {
1073 fdret
= FLOW_DISSECT_RET_OUT_GOOD
;
1076 key_control
->flags
|= FLOW_DIS_FIRST_FRAG
;
1078 FLOW_DISSECTOR_F_PARSE_1ST_FRAG
)) {
1079 fdret
= FLOW_DISSECT_RET_OUT_GOOD
;
1087 case htons(ETH_P_IPV6
): {
1088 const struct ipv6hdr
*iph
;
1089 struct ipv6hdr _iph
;
1091 iph
= __skb_header_pointer(skb
, nhoff
, sizeof(_iph
), data
, hlen
, &_iph
);
1093 fdret
= FLOW_DISSECT_RET_OUT_BAD
;
1097 ip_proto
= iph
->nexthdr
;
1098 nhoff
+= sizeof(struct ipv6hdr
);
1100 if (dissector_uses_key(flow_dissector
,
1101 FLOW_DISSECTOR_KEY_IPV6_ADDRS
)) {
1102 key_addrs
= skb_flow_dissector_target(flow_dissector
,
1103 FLOW_DISSECTOR_KEY_IPV6_ADDRS
,
1106 memcpy(&key_addrs
->v6addrs
.src
, &iph
->saddr
,
1107 sizeof(key_addrs
->v6addrs
.src
));
1108 memcpy(&key_addrs
->v6addrs
.dst
, &iph
->daddr
,
1109 sizeof(key_addrs
->v6addrs
.dst
));
1110 key_control
->addr_type
= FLOW_DISSECTOR_KEY_IPV6_ADDRS
;
1113 if ((dissector_uses_key(flow_dissector
,
1114 FLOW_DISSECTOR_KEY_FLOW_LABEL
) ||
1115 (flags
& FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL
)) &&
1116 ip6_flowlabel(iph
)) {
1117 __be32 flow_label
= ip6_flowlabel(iph
);
1119 if (dissector_uses_key(flow_dissector
,
1120 FLOW_DISSECTOR_KEY_FLOW_LABEL
)) {
1121 key_tags
= skb_flow_dissector_target(flow_dissector
,
1122 FLOW_DISSECTOR_KEY_FLOW_LABEL
,
1124 key_tags
->flow_label
= ntohl(flow_label
);
1126 if (flags
& FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL
) {
1127 fdret
= FLOW_DISSECT_RET_OUT_GOOD
;
1132 __skb_flow_dissect_ipv6(skb
, flow_dissector
,
1133 target_container
, data
, iph
);
1137 case htons(ETH_P_8021AD
):
1138 case htons(ETH_P_8021Q
): {
1139 const struct vlan_hdr
*vlan
= NULL
;
1140 struct vlan_hdr _vlan
;
1141 __be16 saved_vlan_tpid
= proto
;
1143 if (dissector_vlan
== FLOW_DISSECTOR_KEY_MAX
&&
1144 skb
&& skb_vlan_tag_present(skb
)) {
1145 proto
= skb
->protocol
;
1147 vlan
= __skb_header_pointer(skb
, nhoff
, sizeof(_vlan
),
1148 data
, hlen
, &_vlan
);
1150 fdret
= FLOW_DISSECT_RET_OUT_BAD
;
1154 proto
= vlan
->h_vlan_encapsulated_proto
;
1155 nhoff
+= sizeof(*vlan
);
1158 if (dissector_vlan
== FLOW_DISSECTOR_KEY_MAX
) {
1159 dissector_vlan
= FLOW_DISSECTOR_KEY_VLAN
;
1160 } else if (dissector_vlan
== FLOW_DISSECTOR_KEY_VLAN
) {
1161 dissector_vlan
= FLOW_DISSECTOR_KEY_CVLAN
;
1163 fdret
= FLOW_DISSECT_RET_PROTO_AGAIN
;
1167 if (dissector_uses_key(flow_dissector
, dissector_vlan
)) {
1168 key_vlan
= skb_flow_dissector_target(flow_dissector
,
1173 key_vlan
->vlan_id
= skb_vlan_tag_get_id(skb
);
1174 key_vlan
->vlan_priority
= skb_vlan_tag_get_prio(skb
);
1176 key_vlan
->vlan_id
= ntohs(vlan
->h_vlan_TCI
) &
1178 key_vlan
->vlan_priority
=
1179 (ntohs(vlan
->h_vlan_TCI
) &
1180 VLAN_PRIO_MASK
) >> VLAN_PRIO_SHIFT
;
1182 key_vlan
->vlan_tpid
= saved_vlan_tpid
;
1185 fdret
= FLOW_DISSECT_RET_PROTO_AGAIN
;
1188 case htons(ETH_P_PPP_SES
): {
1190 struct pppoe_hdr hdr
;
1193 hdr
= __skb_header_pointer(skb
, nhoff
, sizeof(_hdr
), data
, hlen
, &_hdr
);
1195 fdret
= FLOW_DISSECT_RET_OUT_BAD
;
1200 nhoff
+= PPPOE_SES_HLEN
;
1203 proto
= htons(ETH_P_IP
);
1204 fdret
= FLOW_DISSECT_RET_PROTO_AGAIN
;
1206 case htons(PPP_IPV6
):
1207 proto
= htons(ETH_P_IPV6
);
1208 fdret
= FLOW_DISSECT_RET_PROTO_AGAIN
;
1211 fdret
= FLOW_DISSECT_RET_OUT_BAD
;
1216 case htons(ETH_P_TIPC
): {
1217 struct tipc_basic_hdr
*hdr
, _hdr
;
1219 hdr
= __skb_header_pointer(skb
, nhoff
, sizeof(_hdr
),
1222 fdret
= FLOW_DISSECT_RET_OUT_BAD
;
1226 if (dissector_uses_key(flow_dissector
,
1227 FLOW_DISSECTOR_KEY_TIPC
)) {
1228 key_addrs
= skb_flow_dissector_target(flow_dissector
,
1229 FLOW_DISSECTOR_KEY_TIPC
,
1231 key_addrs
->tipckey
.key
= tipc_hdr_rps_key(hdr
);
1232 key_control
->addr_type
= FLOW_DISSECTOR_KEY_TIPC
;
1234 fdret
= FLOW_DISSECT_RET_OUT_GOOD
;
1238 case htons(ETH_P_MPLS_UC
):
1239 case htons(ETH_P_MPLS_MC
):
1240 fdret
= __skb_flow_dissect_mpls(skb
, flow_dissector
,
1241 target_container
, data
,
1242 nhoff
, hlen
, mpls_lse
,
1244 nhoff
+= sizeof(struct mpls_label
);
1247 case htons(ETH_P_FCOE
):
1248 if ((hlen
- nhoff
) < FCOE_HEADER_LEN
) {
1249 fdret
= FLOW_DISSECT_RET_OUT_BAD
;
1253 nhoff
+= FCOE_HEADER_LEN
;
1254 fdret
= FLOW_DISSECT_RET_OUT_GOOD
;
1257 case htons(ETH_P_ARP
):
1258 case htons(ETH_P_RARP
):
1259 fdret
= __skb_flow_dissect_arp(skb
, flow_dissector
,
1260 target_container
, data
,
1264 case htons(ETH_P_BATMAN
):
1265 fdret
= __skb_flow_dissect_batadv(skb
, key_control
, data
,
1266 &proto
, &nhoff
, hlen
, flags
);
1269 case htons(ETH_P_1588
): {
1270 struct ptp_header
*hdr
, _hdr
;
1272 hdr
= __skb_header_pointer(skb
, nhoff
, sizeof(_hdr
), data
,
1275 fdret
= FLOW_DISSECT_RET_OUT_BAD
;
1279 nhoff
+= ntohs(hdr
->message_length
);
1280 fdret
= FLOW_DISSECT_RET_OUT_GOOD
;
1285 fdret
= FLOW_DISSECT_RET_OUT_BAD
;
1289 /* Process result of proto processing */
1291 case FLOW_DISSECT_RET_OUT_GOOD
:
1293 case FLOW_DISSECT_RET_PROTO_AGAIN
:
1294 if (skb_flow_dissect_allowed(&num_hdrs
))
1297 case FLOW_DISSECT_RET_CONTINUE
:
1298 case FLOW_DISSECT_RET_IPPROTO_AGAIN
:
1300 case FLOW_DISSECT_RET_OUT_BAD
:
1306 fdret
= FLOW_DISSECT_RET_CONTINUE
;
1310 fdret
= __skb_flow_dissect_gre(skb
, key_control
, flow_dissector
,
1311 target_container
, data
,
1312 &proto
, &nhoff
, &hlen
, flags
);
1316 case NEXTHDR_ROUTING
:
1317 case NEXTHDR_DEST
: {
1318 u8 _opthdr
[2], *opthdr
;
1320 if (proto
!= htons(ETH_P_IPV6
))
1323 opthdr
= __skb_header_pointer(skb
, nhoff
, sizeof(_opthdr
),
1324 data
, hlen
, &_opthdr
);
1326 fdret
= FLOW_DISSECT_RET_OUT_BAD
;
1330 ip_proto
= opthdr
[0];
1331 nhoff
+= (opthdr
[1] + 1) << 3;
1333 fdret
= FLOW_DISSECT_RET_IPPROTO_AGAIN
;
1336 case NEXTHDR_FRAGMENT
: {
1337 struct frag_hdr _fh
, *fh
;
1339 if (proto
!= htons(ETH_P_IPV6
))
1342 fh
= __skb_header_pointer(skb
, nhoff
, sizeof(_fh
),
1346 fdret
= FLOW_DISSECT_RET_OUT_BAD
;
1350 key_control
->flags
|= FLOW_DIS_IS_FRAGMENT
;
1352 nhoff
+= sizeof(_fh
);
1353 ip_proto
= fh
->nexthdr
;
1355 if (!(fh
->frag_off
& htons(IP6_OFFSET
))) {
1356 key_control
->flags
|= FLOW_DIS_FIRST_FRAG
;
1357 if (flags
& FLOW_DISSECTOR_F_PARSE_1ST_FRAG
) {
1358 fdret
= FLOW_DISSECT_RET_IPPROTO_AGAIN
;
1363 fdret
= FLOW_DISSECT_RET_OUT_GOOD
;
1367 proto
= htons(ETH_P_IP
);
1369 key_control
->flags
|= FLOW_DIS_ENCAPSULATION
;
1370 if (flags
& FLOW_DISSECTOR_F_STOP_AT_ENCAP
) {
1371 fdret
= FLOW_DISSECT_RET_OUT_GOOD
;
1375 fdret
= FLOW_DISSECT_RET_PROTO_AGAIN
;
1379 proto
= htons(ETH_P_IPV6
);
1381 key_control
->flags
|= FLOW_DIS_ENCAPSULATION
;
1382 if (flags
& FLOW_DISSECTOR_F_STOP_AT_ENCAP
) {
1383 fdret
= FLOW_DISSECT_RET_OUT_GOOD
;
1387 fdret
= FLOW_DISSECT_RET_PROTO_AGAIN
;
1392 proto
= htons(ETH_P_MPLS_UC
);
1393 fdret
= FLOW_DISSECT_RET_PROTO_AGAIN
;
1397 __skb_flow_dissect_tcp(skb
, flow_dissector
, target_container
,
1402 case IPPROTO_ICMPV6
:
1403 __skb_flow_dissect_icmp(skb
, flow_dissector
, target_container
,
1411 if (!(key_control
->flags
& FLOW_DIS_IS_FRAGMENT
))
1412 __skb_flow_dissect_ports(skb
, flow_dissector
, target_container
,
1413 data
, nhoff
, ip_proto
, hlen
);
1415 /* Process result of IP proto processing */
1417 case FLOW_DISSECT_RET_PROTO_AGAIN
:
1418 if (skb_flow_dissect_allowed(&num_hdrs
))
1421 case FLOW_DISSECT_RET_IPPROTO_AGAIN
:
1422 if (skb_flow_dissect_allowed(&num_hdrs
))
1423 goto ip_proto_again
;
1425 case FLOW_DISSECT_RET_OUT_GOOD
:
1426 case FLOW_DISSECT_RET_CONTINUE
:
1428 case FLOW_DISSECT_RET_OUT_BAD
:
1437 key_control
->thoff
= min_t(u16
, nhoff
, skb
? skb
->len
: hlen
);
1438 key_basic
->n_proto
= proto
;
1439 key_basic
->ip_proto
= ip_proto
;
1447 EXPORT_SYMBOL(__skb_flow_dissect
);
1449 static siphash_key_t hashrnd __read_mostly
;
1450 static __always_inline
void __flow_hash_secret_init(void)
1452 net_get_random_once(&hashrnd
, sizeof(hashrnd
));
1455 static const void *flow_keys_hash_start(const struct flow_keys
*flow
)
1457 BUILD_BUG_ON(FLOW_KEYS_HASH_OFFSET
% SIPHASH_ALIGNMENT
);
1458 return &flow
->FLOW_KEYS_HASH_START_FIELD
;
1461 static inline size_t flow_keys_hash_length(const struct flow_keys
*flow
)
1463 size_t diff
= FLOW_KEYS_HASH_OFFSET
+ sizeof(flow
->addrs
);
1465 BUILD_BUG_ON((sizeof(*flow
) - FLOW_KEYS_HASH_OFFSET
) % sizeof(u32
));
1467 switch (flow
->control
.addr_type
) {
1468 case FLOW_DISSECTOR_KEY_IPV4_ADDRS
:
1469 diff
-= sizeof(flow
->addrs
.v4addrs
);
1471 case FLOW_DISSECTOR_KEY_IPV6_ADDRS
:
1472 diff
-= sizeof(flow
->addrs
.v6addrs
);
1474 case FLOW_DISSECTOR_KEY_TIPC
:
1475 diff
-= sizeof(flow
->addrs
.tipckey
);
1478 return sizeof(*flow
) - diff
;
1481 __be32
flow_get_u32_src(const struct flow_keys
*flow
)
1483 switch (flow
->control
.addr_type
) {
1484 case FLOW_DISSECTOR_KEY_IPV4_ADDRS
:
1485 return flow
->addrs
.v4addrs
.src
;
1486 case FLOW_DISSECTOR_KEY_IPV6_ADDRS
:
1487 return (__force __be32
)ipv6_addr_hash(
1488 &flow
->addrs
.v6addrs
.src
);
1489 case FLOW_DISSECTOR_KEY_TIPC
:
1490 return flow
->addrs
.tipckey
.key
;
1495 EXPORT_SYMBOL(flow_get_u32_src
);
1497 __be32
flow_get_u32_dst(const struct flow_keys
*flow
)
1499 switch (flow
->control
.addr_type
) {
1500 case FLOW_DISSECTOR_KEY_IPV4_ADDRS
:
1501 return flow
->addrs
.v4addrs
.dst
;
1502 case FLOW_DISSECTOR_KEY_IPV6_ADDRS
:
1503 return (__force __be32
)ipv6_addr_hash(
1504 &flow
->addrs
.v6addrs
.dst
);
1509 EXPORT_SYMBOL(flow_get_u32_dst
);
1511 /* Sort the source and destination IP and the ports,
1512 * to have consistent hash within the two directions
1514 static inline void __flow_hash_consistentify(struct flow_keys
*keys
)
1518 switch (keys
->control
.addr_type
) {
1519 case FLOW_DISSECTOR_KEY_IPV4_ADDRS
:
1520 addr_diff
= (__force u32
)keys
->addrs
.v4addrs
.dst
-
1521 (__force u32
)keys
->addrs
.v4addrs
.src
;
1523 swap(keys
->addrs
.v4addrs
.src
, keys
->addrs
.v4addrs
.dst
);
1525 if ((__force u16
)keys
->ports
.dst
<
1526 (__force u16
)keys
->ports
.src
) {
1527 swap(keys
->ports
.src
, keys
->ports
.dst
);
1530 case FLOW_DISSECTOR_KEY_IPV6_ADDRS
:
1531 addr_diff
= memcmp(&keys
->addrs
.v6addrs
.dst
,
1532 &keys
->addrs
.v6addrs
.src
,
1533 sizeof(keys
->addrs
.v6addrs
.dst
));
1534 if (addr_diff
< 0) {
1535 for (i
= 0; i
< 4; i
++)
1536 swap(keys
->addrs
.v6addrs
.src
.s6_addr32
[i
],
1537 keys
->addrs
.v6addrs
.dst
.s6_addr32
[i
]);
1539 if ((__force u16
)keys
->ports
.dst
<
1540 (__force u16
)keys
->ports
.src
) {
1541 swap(keys
->ports
.src
, keys
->ports
.dst
);
1547 static inline u32
__flow_hash_from_keys(struct flow_keys
*keys
,
1548 const siphash_key_t
*keyval
)
1552 __flow_hash_consistentify(keys
);
1554 hash
= siphash(flow_keys_hash_start(keys
),
1555 flow_keys_hash_length(keys
), keyval
);
1562 u32
flow_hash_from_keys(struct flow_keys
*keys
)
1564 __flow_hash_secret_init();
1565 return __flow_hash_from_keys(keys
, &hashrnd
);
1567 EXPORT_SYMBOL(flow_hash_from_keys
);
1569 static inline u32
___skb_get_hash(const struct sk_buff
*skb
,
1570 struct flow_keys
*keys
,
1571 const siphash_key_t
*keyval
)
1573 skb_flow_dissect_flow_keys(skb
, keys
,
1574 FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL
);
1576 return __flow_hash_from_keys(keys
, keyval
);
1579 struct _flow_keys_digest_data
{
1588 void make_flow_keys_digest(struct flow_keys_digest
*digest
,
1589 const struct flow_keys
*flow
)
1591 struct _flow_keys_digest_data
*data
=
1592 (struct _flow_keys_digest_data
*)digest
;
1594 BUILD_BUG_ON(sizeof(*data
) > sizeof(*digest
));
1596 memset(digest
, 0, sizeof(*digest
));
1598 data
->n_proto
= flow
->basic
.n_proto
;
1599 data
->ip_proto
= flow
->basic
.ip_proto
;
1600 data
->ports
= flow
->ports
.ports
;
1601 data
->src
= flow
->addrs
.v4addrs
.src
;
1602 data
->dst
= flow
->addrs
.v4addrs
.dst
;
1604 EXPORT_SYMBOL(make_flow_keys_digest
);
1606 static struct flow_dissector flow_keys_dissector_symmetric __read_mostly
;
1608 u32
__skb_get_hash_symmetric(const struct sk_buff
*skb
)
1610 struct flow_keys keys
;
1612 __flow_hash_secret_init();
1614 memset(&keys
, 0, sizeof(keys
));
1615 __skb_flow_dissect(NULL
, skb
, &flow_keys_dissector_symmetric
,
1616 &keys
, NULL
, 0, 0, 0,
1617 FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL
);
1619 return __flow_hash_from_keys(&keys
, &hashrnd
);
1621 EXPORT_SYMBOL_GPL(__skb_get_hash_symmetric
);
1624 * __skb_get_hash: calculate a flow hash
1625 * @skb: sk_buff to calculate flow hash from
1627 * This function calculates a flow hash based on src/dst addresses
1628 * and src/dst port numbers. Sets hash in skb to non-zero hash value
1629 * on success, zero indicates no valid hash. Also, sets l4_hash in skb
1630 * if hash is a canonical 4-tuple hash over transport ports.
1632 void __skb_get_hash(struct sk_buff
*skb
)
1634 struct flow_keys keys
;
1637 __flow_hash_secret_init();
1639 hash
= ___skb_get_hash(skb
, &keys
, &hashrnd
);
1641 __skb_set_sw_hash(skb
, hash
, flow_keys_have_l4(&keys
));
1643 EXPORT_SYMBOL(__skb_get_hash
);
1645 __u32
skb_get_hash_perturb(const struct sk_buff
*skb
,
1646 const siphash_key_t
*perturb
)
1648 struct flow_keys keys
;
1650 return ___skb_get_hash(skb
, &keys
, perturb
);
1652 EXPORT_SYMBOL(skb_get_hash_perturb
);
1654 u32
__skb_get_poff(const struct sk_buff
*skb
, const void *data
,
1655 const struct flow_keys_basic
*keys
, int hlen
)
1657 u32 poff
= keys
->control
.thoff
;
1659 /* skip L4 headers for fragments after the first */
1660 if ((keys
->control
.flags
& FLOW_DIS_IS_FRAGMENT
) &&
1661 !(keys
->control
.flags
& FLOW_DIS_FIRST_FRAG
))
1664 switch (keys
->basic
.ip_proto
) {
1666 /* access doff as u8 to avoid unaligned access */
1670 doff
= __skb_header_pointer(skb
, poff
+ 12, sizeof(_doff
),
1671 data
, hlen
, &_doff
);
1675 poff
+= max_t(u32
, sizeof(struct tcphdr
), (*doff
& 0xF0) >> 2);
1679 case IPPROTO_UDPLITE
:
1680 poff
+= sizeof(struct udphdr
);
1682 /* For the rest, we do not really care about header
1683 * extensions at this point for now.
1686 poff
+= sizeof(struct icmphdr
);
1688 case IPPROTO_ICMPV6
:
1689 poff
+= sizeof(struct icmp6hdr
);
1692 poff
+= sizeof(struct igmphdr
);
1695 poff
+= sizeof(struct dccp_hdr
);
1698 poff
+= sizeof(struct sctphdr
);
1706 * skb_get_poff - get the offset to the payload
1707 * @skb: sk_buff to get the payload offset from
1709 * The function will get the offset to the payload as far as it could
1710 * be dissected. The main user is currently BPF, so that we can dynamically
1711 * truncate packets without needing to push actual payload to the user
1712 * space and can analyze headers only, instead.
1714 u32
skb_get_poff(const struct sk_buff
*skb
)
1716 struct flow_keys_basic keys
;
1718 if (!skb_flow_dissect_flow_keys_basic(NULL
, skb
, &keys
,
1722 return __skb_get_poff(skb
, skb
->data
, &keys
, skb_headlen(skb
));
1725 __u32
__get_hash_from_flowi6(const struct flowi6
*fl6
, struct flow_keys
*keys
)
1727 memset(keys
, 0, sizeof(*keys
));
1729 memcpy(&keys
->addrs
.v6addrs
.src
, &fl6
->saddr
,
1730 sizeof(keys
->addrs
.v6addrs
.src
));
1731 memcpy(&keys
->addrs
.v6addrs
.dst
, &fl6
->daddr
,
1732 sizeof(keys
->addrs
.v6addrs
.dst
));
1733 keys
->control
.addr_type
= FLOW_DISSECTOR_KEY_IPV6_ADDRS
;
1734 keys
->ports
.src
= fl6
->fl6_sport
;
1735 keys
->ports
.dst
= fl6
->fl6_dport
;
1736 keys
->keyid
.keyid
= fl6
->fl6_gre_key
;
1737 keys
->tags
.flow_label
= (__force u32
)flowi6_get_flowlabel(fl6
);
1738 keys
->basic
.ip_proto
= fl6
->flowi6_proto
;
1740 return flow_hash_from_keys(keys
);
1742 EXPORT_SYMBOL(__get_hash_from_flowi6
);
1744 static const struct flow_dissector_key flow_keys_dissector_keys
[] = {
1746 .key_id
= FLOW_DISSECTOR_KEY_CONTROL
,
1747 .offset
= offsetof(struct flow_keys
, control
),
1750 .key_id
= FLOW_DISSECTOR_KEY_BASIC
,
1751 .offset
= offsetof(struct flow_keys
, basic
),
1754 .key_id
= FLOW_DISSECTOR_KEY_IPV4_ADDRS
,
1755 .offset
= offsetof(struct flow_keys
, addrs
.v4addrs
),
1758 .key_id
= FLOW_DISSECTOR_KEY_IPV6_ADDRS
,
1759 .offset
= offsetof(struct flow_keys
, addrs
.v6addrs
),
1762 .key_id
= FLOW_DISSECTOR_KEY_TIPC
,
1763 .offset
= offsetof(struct flow_keys
, addrs
.tipckey
),
1766 .key_id
= FLOW_DISSECTOR_KEY_PORTS
,
1767 .offset
= offsetof(struct flow_keys
, ports
),
1770 .key_id
= FLOW_DISSECTOR_KEY_VLAN
,
1771 .offset
= offsetof(struct flow_keys
, vlan
),
1774 .key_id
= FLOW_DISSECTOR_KEY_FLOW_LABEL
,
1775 .offset
= offsetof(struct flow_keys
, tags
),
1778 .key_id
= FLOW_DISSECTOR_KEY_GRE_KEYID
,
1779 .offset
= offsetof(struct flow_keys
, keyid
),
1783 static const struct flow_dissector_key flow_keys_dissector_symmetric_keys
[] = {
1785 .key_id
= FLOW_DISSECTOR_KEY_CONTROL
,
1786 .offset
= offsetof(struct flow_keys
, control
),
1789 .key_id
= FLOW_DISSECTOR_KEY_BASIC
,
1790 .offset
= offsetof(struct flow_keys
, basic
),
1793 .key_id
= FLOW_DISSECTOR_KEY_IPV4_ADDRS
,
1794 .offset
= offsetof(struct flow_keys
, addrs
.v4addrs
),
1797 .key_id
= FLOW_DISSECTOR_KEY_IPV6_ADDRS
,
1798 .offset
= offsetof(struct flow_keys
, addrs
.v6addrs
),
1801 .key_id
= FLOW_DISSECTOR_KEY_PORTS
,
1802 .offset
= offsetof(struct flow_keys
, ports
),
1806 static const struct flow_dissector_key flow_keys_basic_dissector_keys
[] = {
1808 .key_id
= FLOW_DISSECTOR_KEY_CONTROL
,
1809 .offset
= offsetof(struct flow_keys
, control
),
1812 .key_id
= FLOW_DISSECTOR_KEY_BASIC
,
1813 .offset
= offsetof(struct flow_keys
, basic
),
1817 struct flow_dissector flow_keys_dissector __read_mostly
;
1818 EXPORT_SYMBOL(flow_keys_dissector
);
1820 struct flow_dissector flow_keys_basic_dissector __read_mostly
;
1821 EXPORT_SYMBOL(flow_keys_basic_dissector
);
1823 static int __init
init_default_flow_dissectors(void)
1825 skb_flow_dissector_init(&flow_keys_dissector
,
1826 flow_keys_dissector_keys
,
1827 ARRAY_SIZE(flow_keys_dissector_keys
));
1828 skb_flow_dissector_init(&flow_keys_dissector_symmetric
,
1829 flow_keys_dissector_symmetric_keys
,
1830 ARRAY_SIZE(flow_keys_dissector_symmetric_keys
));
1831 skb_flow_dissector_init(&flow_keys_basic_dissector
,
1832 flow_keys_basic_dissector_keys
,
1833 ARRAY_SIZE(flow_keys_basic_dissector_keys
));
1836 core_initcall(init_default_flow_dissectors
);