1 #include <linux/kernel.h>
2 #include <linux/skbuff.h>
3 #include <linux/export.h>
5 #include <linux/ipv6.h>
6 #include <linux/if_vlan.h>
11 #include <linux/igmp.h>
12 #include <linux/icmp.h>
13 #include <linux/sctp.h>
14 #include <linux/dccp.h>
15 #include <linux/if_tunnel.h>
16 #include <linux/if_pppox.h>
17 #include <linux/ppp_defs.h>
18 #include <linux/stddef.h>
19 #include <linux/if_ether.h>
20 #include <linux/mpls.h>
21 #include <net/flow_dissector.h>
22 #include <scsi/fc/fc_fcoe.h>
24 static void dissector_set_key(struct flow_dissector *flow_dissector,
25 enum flow_dissector_key_id key_id)
27 flow_dissector->used_keys |= (1 << key_id);
30 void skb_flow_dissector_init(struct flow_dissector *flow_dissector,
31 const struct flow_dissector_key *key,
32 unsigned int key_count)
36 memset(flow_dissector, 0, sizeof(*flow_dissector));
38 for (i = 0; i < key_count; i++, key++) {
39 /* User should make sure that every key target offset is withing
40 * boundaries of unsigned short.
42 BUG_ON(key->offset > USHRT_MAX);
43 BUG_ON(dissector_uses_key(flow_dissector,
46 dissector_set_key(flow_dissector, key->key_id);
47 flow_dissector->offset[key->key_id] = key->offset;
50 /* Ensure that the dissector always includes control and basic key.
51 * That way we are able to avoid handling lack of these in fast path.
53 BUG_ON(!dissector_uses_key(flow_dissector,
54 FLOW_DISSECTOR_KEY_CONTROL));
55 BUG_ON(!dissector_uses_key(flow_dissector,
56 FLOW_DISSECTOR_KEY_BASIC));
58 EXPORT_SYMBOL(skb_flow_dissector_init);
61 * __skb_flow_get_ports - extract the upper layer ports and return them
62 * @skb: sk_buff to extract the ports from
63 * @thoff: transport header offset
64 * @ip_proto: protocol for which to get port offset
65 * @data: raw buffer pointer to the packet, if NULL use skb->data
66 * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
68 * The function will try to retrieve the ports at offset thoff + poff where poff
69 * is the protocol port offset returned from proto_ports_offset
71 __be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto,
74 int poff = proto_ports_offset(ip_proto);
78 hlen = skb_headlen(skb);
82 __be32 *ports, _ports;
84 ports = __skb_header_pointer(skb, thoff + poff,
85 sizeof(_ports), data, hlen, &_ports);
92 EXPORT_SYMBOL(__skb_flow_get_ports);
95 * __skb_flow_dissect - extract the flow_keys struct and return it
96 * @skb: sk_buff to extract the flow from, can be NULL if the rest are specified
97 * @flow_dissector: list of keys to dissect
98 * @target_container: target structure to put dissected values into
99 * @data: raw buffer pointer to the packet, if NULL use skb->data
100 * @proto: protocol for which to get the flow, if @data is NULL use skb->protocol
101 * @nhoff: network header offset, if @data is NULL use skb_network_offset(skb)
102 * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
104 * The function will try to retrieve individual keys into target specified
105 * by flow_dissector from either the skbuff or a raw buffer specified by the
108 * Caller must take care of zeroing target container memory.
110 bool __skb_flow_dissect(const struct sk_buff *skb,
111 struct flow_dissector *flow_dissector,
112 void *target_container,
113 void *data, __be16 proto, int nhoff, int hlen,
116 struct flow_dissector_key_control *key_control;
117 struct flow_dissector_key_basic *key_basic;
118 struct flow_dissector_key_addrs *key_addrs;
119 struct flow_dissector_key_ports *key_ports;
120 struct flow_dissector_key_tags *key_tags;
121 struct flow_dissector_key_vlan *key_vlan;
122 struct flow_dissector_key_keyid *key_keyid;
123 bool skip_vlan = false;
129 proto = skb_vlan_tag_present(skb) ?
130 skb->vlan_proto : skb->protocol;
131 nhoff = skb_network_offset(skb);
132 hlen = skb_headlen(skb);
135 /* It is ensured by skb_flow_dissector_init() that control key will
138 key_control = skb_flow_dissector_target(flow_dissector,
139 FLOW_DISSECTOR_KEY_CONTROL,
142 /* It is ensured by skb_flow_dissector_init() that basic key will
145 key_basic = skb_flow_dissector_target(flow_dissector,
146 FLOW_DISSECTOR_KEY_BASIC,
149 if (dissector_uses_key(flow_dissector,
150 FLOW_DISSECTOR_KEY_ETH_ADDRS)) {
151 struct ethhdr *eth = eth_hdr(skb);
152 struct flow_dissector_key_eth_addrs *key_eth_addrs;
154 key_eth_addrs = skb_flow_dissector_target(flow_dissector,
155 FLOW_DISSECTOR_KEY_ETH_ADDRS,
157 memcpy(key_eth_addrs, ð->h_dest, sizeof(*key_eth_addrs));
162 case htons(ETH_P_IP): {
163 const struct iphdr *iph;
166 iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
167 if (!iph || iph->ihl < 5)
169 nhoff += iph->ihl * 4;
171 ip_proto = iph->protocol;
173 if (dissector_uses_key(flow_dissector,
174 FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
175 key_addrs = skb_flow_dissector_target(flow_dissector,
176 FLOW_DISSECTOR_KEY_IPV4_ADDRS,
179 memcpy(&key_addrs->v4addrs.src, &iph->saddr,
180 sizeof(key_addrs->v4addrs.src));
181 memcpy(&key_addrs->v4addrs.dst, &iph->daddr,
182 sizeof(key_addrs->v4addrs.dst));
183 key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
186 if (ip_is_fragment(iph)) {
187 key_control->flags |= FLOW_DIS_IS_FRAGMENT;
189 if (iph->frag_off & htons(IP_OFFSET)) {
192 key_control->flags |= FLOW_DIS_FIRST_FRAG;
193 if (!(flags & FLOW_DISSECTOR_F_PARSE_1ST_FRAG))
198 if (flags & FLOW_DISSECTOR_F_STOP_AT_L3)
203 case htons(ETH_P_IPV6): {
204 const struct ipv6hdr *iph;
208 iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
212 ip_proto = iph->nexthdr;
213 nhoff += sizeof(struct ipv6hdr);
215 if (dissector_uses_key(flow_dissector,
216 FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
217 key_addrs = skb_flow_dissector_target(flow_dissector,
218 FLOW_DISSECTOR_KEY_IPV6_ADDRS,
221 memcpy(&key_addrs->v6addrs.src, &iph->saddr,
222 sizeof(key_addrs->v6addrs.src));
223 memcpy(&key_addrs->v6addrs.dst, &iph->daddr,
224 sizeof(key_addrs->v6addrs.dst));
225 key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
228 if ((dissector_uses_key(flow_dissector,
229 FLOW_DISSECTOR_KEY_FLOW_LABEL) ||
230 (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL)) &&
231 ip6_flowlabel(iph)) {
232 __be32 flow_label = ip6_flowlabel(iph);
234 if (dissector_uses_key(flow_dissector,
235 FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
236 key_tags = skb_flow_dissector_target(flow_dissector,
237 FLOW_DISSECTOR_KEY_FLOW_LABEL,
239 key_tags->flow_label = ntohl(flow_label);
241 if (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL)
245 if (flags & FLOW_DISSECTOR_F_STOP_AT_L3)
250 case htons(ETH_P_8021AD):
251 case htons(ETH_P_8021Q): {
252 const struct vlan_hdr *vlan;
253 struct vlan_hdr _vlan;
254 bool vlan_tag_present = skb && skb_vlan_tag_present(skb);
256 if (vlan_tag_present)
257 proto = skb->protocol;
259 if (!vlan_tag_present || eth_type_vlan(skb->protocol)) {
260 vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan),
264 proto = vlan->h_vlan_encapsulated_proto;
265 nhoff += sizeof(*vlan);
271 if (dissector_uses_key(flow_dissector,
272 FLOW_DISSECTOR_KEY_VLAN)) {
273 key_vlan = skb_flow_dissector_target(flow_dissector,
274 FLOW_DISSECTOR_KEY_VLAN,
277 if (vlan_tag_present) {
278 key_vlan->vlan_id = skb_vlan_tag_get_id(skb);
279 key_vlan->vlan_priority =
280 (skb_vlan_tag_get_prio(skb) >> VLAN_PRIO_SHIFT);
282 key_vlan->vlan_id = ntohs(vlan->h_vlan_TCI) &
284 key_vlan->vlan_priority =
285 (ntohs(vlan->h_vlan_TCI) &
286 VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
292 case htons(ETH_P_PPP_SES): {
294 struct pppoe_hdr hdr;
297 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
301 nhoff += PPPOE_SES_HLEN;
305 case htons(PPP_IPV6):
311 case htons(ETH_P_TIPC): {
316 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
320 if (dissector_uses_key(flow_dissector,
321 FLOW_DISSECTOR_KEY_TIPC_ADDRS)) {
322 key_addrs = skb_flow_dissector_target(flow_dissector,
323 FLOW_DISSECTOR_KEY_TIPC_ADDRS,
325 key_addrs->tipcaddrs.srcnode = hdr->srcnode;
326 key_control->addr_type = FLOW_DISSECTOR_KEY_TIPC_ADDRS;
331 case htons(ETH_P_MPLS_UC):
332 case htons(ETH_P_MPLS_MC): {
333 struct mpls_label *hdr, _hdr[2];
335 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
340 if ((ntohl(hdr[0].entry) & MPLS_LS_LABEL_MASK) >>
341 MPLS_LS_LABEL_SHIFT == MPLS_LABEL_ENTROPY) {
342 if (dissector_uses_key(flow_dissector,
343 FLOW_DISSECTOR_KEY_MPLS_ENTROPY)) {
344 key_keyid = skb_flow_dissector_target(flow_dissector,
345 FLOW_DISSECTOR_KEY_MPLS_ENTROPY,
347 key_keyid->keyid = hdr[1].entry &
348 htonl(MPLS_LS_LABEL_MASK);
357 case htons(ETH_P_FCOE):
358 if ((hlen - nhoff) < FCOE_HEADER_LEN)
361 nhoff += FCOE_HEADER_LEN;
370 struct gre_base_hdr *hdr, _hdr;
374 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
378 /* Only look inside GRE without routing */
379 if (hdr->flags & GRE_ROUTING)
382 /* Only look inside GRE for version 0 and 1 */
383 gre_ver = ntohs(hdr->flags & GRE_VERSION);
387 proto = hdr->protocol;
389 /* Version1 must be PPTP, and check the flags */
390 if (!(proto == GRE_PROTO_PPP && (hdr->flags & GRE_KEY)))
394 offset += sizeof(struct gre_base_hdr);
396 if (hdr->flags & GRE_CSUM)
397 offset += sizeof(((struct gre_full_hdr *)0)->csum) +
398 sizeof(((struct gre_full_hdr *)0)->reserved1);
400 if (hdr->flags & GRE_KEY) {
404 keyid = __skb_header_pointer(skb, nhoff + offset, sizeof(_keyid),
405 data, hlen, &_keyid);
409 if (dissector_uses_key(flow_dissector,
410 FLOW_DISSECTOR_KEY_GRE_KEYID)) {
411 key_keyid = skb_flow_dissector_target(flow_dissector,
412 FLOW_DISSECTOR_KEY_GRE_KEYID,
415 key_keyid->keyid = *keyid;
417 key_keyid->keyid = *keyid & GRE_PPTP_KEY_MASK;
419 offset += sizeof(((struct gre_full_hdr *)0)->key);
422 if (hdr->flags & GRE_SEQ)
423 offset += sizeof(((struct pptp_gre_header *)0)->seq);
426 if (proto == htons(ETH_P_TEB)) {
427 const struct ethhdr *eth;
430 eth = __skb_header_pointer(skb, nhoff + offset,
435 proto = eth->h_proto;
436 offset += sizeof(*eth);
438 /* Cap headers that we access via pointers at the
439 * end of the Ethernet header as our maximum alignment
440 * at that point is only 2 bytes.
443 hlen = (nhoff + offset);
445 } else { /* version 1, must be PPTP */
446 u8 _ppp_hdr[PPP_HDRLEN];
449 if (hdr->flags & GRE_ACK)
450 offset += sizeof(((struct pptp_gre_header *)0)->ack);
452 ppp_hdr = __skb_header_pointer(skb, nhoff + offset,
454 data, hlen, _ppp_hdr);
458 switch (PPP_PROTOCOL(ppp_hdr)) {
460 proto = htons(ETH_P_IP);
463 proto = htons(ETH_P_IPV6);
466 /* Could probably catch some more like MPLS */
470 offset += PPP_HDRLEN;
474 key_control->flags |= FLOW_DIS_ENCAPSULATION;
475 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
481 case NEXTHDR_ROUTING:
483 u8 _opthdr[2], *opthdr;
485 if (proto != htons(ETH_P_IPV6))
488 opthdr = __skb_header_pointer(skb, nhoff, sizeof(_opthdr),
489 data, hlen, &_opthdr);
493 ip_proto = opthdr[0];
494 nhoff += (opthdr[1] + 1) << 3;
498 case NEXTHDR_FRAGMENT: {
499 struct frag_hdr _fh, *fh;
501 if (proto != htons(ETH_P_IPV6))
504 fh = __skb_header_pointer(skb, nhoff, sizeof(_fh),
510 key_control->flags |= FLOW_DIS_IS_FRAGMENT;
512 nhoff += sizeof(_fh);
513 ip_proto = fh->nexthdr;
515 if (!(fh->frag_off & htons(IP6_OFFSET))) {
516 key_control->flags |= FLOW_DIS_FIRST_FRAG;
517 if (flags & FLOW_DISSECTOR_F_PARSE_1ST_FRAG)
523 proto = htons(ETH_P_IP);
525 key_control->flags |= FLOW_DIS_ENCAPSULATION;
526 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
531 proto = htons(ETH_P_IPV6);
533 key_control->flags |= FLOW_DIS_ENCAPSULATION;
534 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
539 proto = htons(ETH_P_MPLS_UC);
545 if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS) &&
546 !(key_control->flags & FLOW_DIS_IS_FRAGMENT)) {
547 key_ports = skb_flow_dissector_target(flow_dissector,
548 FLOW_DISSECTOR_KEY_PORTS,
550 key_ports->ports = __skb_flow_get_ports(skb, nhoff, ip_proto,
558 key_control->thoff = min_t(u16, nhoff, skb ? skb->len : hlen);
559 key_basic->n_proto = proto;
560 key_basic->ip_proto = ip_proto;
568 EXPORT_SYMBOL(__skb_flow_dissect);
570 static siphash_key_t hashrnd __read_mostly;
571 static __always_inline void __flow_hash_secret_init(void)
573 net_get_random_once(&hashrnd, sizeof(hashrnd));
576 static const void *flow_keys_hash_start(const struct flow_keys *flow)
578 BUILD_BUG_ON(FLOW_KEYS_HASH_OFFSET % SIPHASH_ALIGNMENT);
579 return &flow->FLOW_KEYS_HASH_START_FIELD;
582 static inline size_t flow_keys_hash_length(const struct flow_keys *flow)
584 size_t len = offsetof(typeof(*flow), addrs) - FLOW_KEYS_HASH_OFFSET;
586 switch (flow->control.addr_type) {
587 case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
588 len += sizeof(flow->addrs.v4addrs);
590 case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
591 len += sizeof(flow->addrs.v6addrs);
593 case FLOW_DISSECTOR_KEY_TIPC_ADDRS:
594 len += sizeof(flow->addrs.tipcaddrs);
600 __be32 flow_get_u32_src(const struct flow_keys *flow)
602 switch (flow->control.addr_type) {
603 case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
604 return flow->addrs.v4addrs.src;
605 case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
606 return (__force __be32)ipv6_addr_hash(
607 &flow->addrs.v6addrs.src);
608 case FLOW_DISSECTOR_KEY_TIPC_ADDRS:
609 return flow->addrs.tipcaddrs.srcnode;
614 EXPORT_SYMBOL(flow_get_u32_src);
616 __be32 flow_get_u32_dst(const struct flow_keys *flow)
618 switch (flow->control.addr_type) {
619 case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
620 return flow->addrs.v4addrs.dst;
621 case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
622 return (__force __be32)ipv6_addr_hash(
623 &flow->addrs.v6addrs.dst);
628 EXPORT_SYMBOL(flow_get_u32_dst);
630 static inline void __flow_hash_consistentify(struct flow_keys *keys)
634 switch (keys->control.addr_type) {
635 case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
636 addr_diff = (__force u32)keys->addrs.v4addrs.dst -
637 (__force u32)keys->addrs.v4addrs.src;
638 if ((addr_diff < 0) ||
640 ((__force u16)keys->ports.dst <
641 (__force u16)keys->ports.src))) {
642 swap(keys->addrs.v4addrs.src, keys->addrs.v4addrs.dst);
643 swap(keys->ports.src, keys->ports.dst);
646 case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
647 addr_diff = memcmp(&keys->addrs.v6addrs.dst,
648 &keys->addrs.v6addrs.src,
649 sizeof(keys->addrs.v6addrs.dst));
650 if ((addr_diff < 0) ||
652 ((__force u16)keys->ports.dst <
653 (__force u16)keys->ports.src))) {
654 for (i = 0; i < 4; i++)
655 swap(keys->addrs.v6addrs.src.s6_addr32[i],
656 keys->addrs.v6addrs.dst.s6_addr32[i]);
657 swap(keys->ports.src, keys->ports.dst);
663 static inline u32 __flow_hash_from_keys(struct flow_keys *keys,
664 const siphash_key_t *keyval)
668 __flow_hash_consistentify(keys);
670 hash = siphash(flow_keys_hash_start(keys),
671 flow_keys_hash_length(keys), keyval);
678 u32 flow_hash_from_keys(struct flow_keys *keys)
680 __flow_hash_secret_init();
681 return __flow_hash_from_keys(keys, &hashrnd);
683 EXPORT_SYMBOL(flow_hash_from_keys);
685 static inline u32 ___skb_get_hash(const struct sk_buff *skb,
686 struct flow_keys *keys,
687 const siphash_key_t *keyval)
689 skb_flow_dissect_flow_keys(skb, keys,
690 FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
692 return __flow_hash_from_keys(keys, keyval);
695 struct _flow_keys_digest_data {
704 void make_flow_keys_digest(struct flow_keys_digest *digest,
705 const struct flow_keys *flow)
707 struct _flow_keys_digest_data *data =
708 (struct _flow_keys_digest_data *)digest;
710 BUILD_BUG_ON(sizeof(*data) > sizeof(*digest));
712 memset(digest, 0, sizeof(*digest));
714 data->n_proto = flow->basic.n_proto;
715 data->ip_proto = flow->basic.ip_proto;
716 data->ports = flow->ports.ports;
717 data->src = flow->addrs.v4addrs.src;
718 data->dst = flow->addrs.v4addrs.dst;
720 EXPORT_SYMBOL(make_flow_keys_digest);
722 static struct flow_dissector flow_keys_dissector_symmetric __read_mostly;
724 u32 __skb_get_hash_symmetric(struct sk_buff *skb)
726 struct flow_keys keys;
728 __flow_hash_secret_init();
730 memset(&keys, 0, sizeof(keys));
731 __skb_flow_dissect(skb, &flow_keys_dissector_symmetric, &keys,
733 FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
735 return __flow_hash_from_keys(&keys, &hashrnd);
737 EXPORT_SYMBOL_GPL(__skb_get_hash_symmetric);
740 * __skb_get_hash: calculate a flow hash
741 * @skb: sk_buff to calculate flow hash from
743 * This function calculates a flow hash based on src/dst addresses
744 * and src/dst port numbers. Sets hash in skb to non-zero hash value
745 * on success, zero indicates no valid hash. Also, sets l4_hash in skb
746 * if hash is a canonical 4-tuple hash over transport ports.
748 void __skb_get_hash(struct sk_buff *skb)
750 struct flow_keys keys;
753 __flow_hash_secret_init();
755 hash = ___skb_get_hash(skb, &keys, &hashrnd);
757 __skb_set_sw_hash(skb, hash, flow_keys_have_l4(&keys));
759 EXPORT_SYMBOL(__skb_get_hash);
761 __u32 skb_get_hash_perturb(const struct sk_buff *skb,
762 const siphash_key_t *perturb)
764 struct flow_keys keys;
766 return ___skb_get_hash(skb, &keys, perturb);
768 EXPORT_SYMBOL(skb_get_hash_perturb);
770 __u32 __skb_get_hash_flowi6(struct sk_buff *skb, const struct flowi6 *fl6)
772 struct flow_keys keys;
774 memset(&keys, 0, sizeof(keys));
776 memcpy(&keys.addrs.v6addrs.src, &fl6->saddr,
777 sizeof(keys.addrs.v6addrs.src));
778 memcpy(&keys.addrs.v6addrs.dst, &fl6->daddr,
779 sizeof(keys.addrs.v6addrs.dst));
780 keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
781 keys.ports.src = fl6->fl6_sport;
782 keys.ports.dst = fl6->fl6_dport;
783 keys.keyid.keyid = fl6->fl6_gre_key;
784 keys.tags.flow_label = (__force u32)fl6->flowlabel;
785 keys.basic.ip_proto = fl6->flowi6_proto;
787 __skb_set_sw_hash(skb, flow_hash_from_keys(&keys),
788 flow_keys_have_l4(&keys));
792 EXPORT_SYMBOL(__skb_get_hash_flowi6);
794 __u32 __skb_get_hash_flowi4(struct sk_buff *skb, const struct flowi4 *fl4)
796 struct flow_keys keys;
798 memset(&keys, 0, sizeof(keys));
800 keys.addrs.v4addrs.src = fl4->saddr;
801 keys.addrs.v4addrs.dst = fl4->daddr;
802 keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
803 keys.ports.src = fl4->fl4_sport;
804 keys.ports.dst = fl4->fl4_dport;
805 keys.keyid.keyid = fl4->fl4_gre_key;
806 keys.basic.ip_proto = fl4->flowi4_proto;
808 __skb_set_sw_hash(skb, flow_hash_from_keys(&keys),
809 flow_keys_have_l4(&keys));
813 EXPORT_SYMBOL(__skb_get_hash_flowi4);
815 u32 __skb_get_poff(const struct sk_buff *skb, void *data,
816 const struct flow_keys *keys, int hlen)
818 u32 poff = keys->control.thoff;
820 /* skip L4 headers for fragments after the first */
821 if ((keys->control.flags & FLOW_DIS_IS_FRAGMENT) &&
822 !(keys->control.flags & FLOW_DIS_FIRST_FRAG))
825 switch (keys->basic.ip_proto) {
827 /* access doff as u8 to avoid unaligned access */
831 doff = __skb_header_pointer(skb, poff + 12, sizeof(_doff),
836 poff += max_t(u32, sizeof(struct tcphdr), (*doff & 0xF0) >> 2);
840 case IPPROTO_UDPLITE:
841 poff += sizeof(struct udphdr);
843 /* For the rest, we do not really care about header
844 * extensions at this point for now.
847 poff += sizeof(struct icmphdr);
850 poff += sizeof(struct icmp6hdr);
853 poff += sizeof(struct igmphdr);
856 poff += sizeof(struct dccp_hdr);
859 poff += sizeof(struct sctphdr);
867 * skb_get_poff - get the offset to the payload
868 * @skb: sk_buff to get the payload offset from
870 * The function will get the offset to the payload as far as it could
871 * be dissected. The main user is currently BPF, so that we can dynamically
872 * truncate packets without needing to push actual payload to the user
873 * space and can analyze headers only, instead.
875 u32 skb_get_poff(const struct sk_buff *skb)
877 struct flow_keys keys;
879 if (!skb_flow_dissect_flow_keys(skb, &keys, 0))
882 return __skb_get_poff(skb, skb->data, &keys, skb_headlen(skb));
885 __u32 __get_hash_from_flowi6(const struct flowi6 *fl6, struct flow_keys *keys)
887 memset(keys, 0, sizeof(*keys));
889 memcpy(&keys->addrs.v6addrs.src, &fl6->saddr,
890 sizeof(keys->addrs.v6addrs.src));
891 memcpy(&keys->addrs.v6addrs.dst, &fl6->daddr,
892 sizeof(keys->addrs.v6addrs.dst));
893 keys->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
894 keys->ports.src = fl6->fl6_sport;
895 keys->ports.dst = fl6->fl6_dport;
896 keys->keyid.keyid = fl6->fl6_gre_key;
897 keys->tags.flow_label = (__force u32)fl6->flowlabel;
898 keys->basic.ip_proto = fl6->flowi6_proto;
900 return flow_hash_from_keys(keys);
902 EXPORT_SYMBOL(__get_hash_from_flowi6);
904 __u32 __get_hash_from_flowi4(const struct flowi4 *fl4, struct flow_keys *keys)
906 memset(keys, 0, sizeof(*keys));
908 keys->addrs.v4addrs.src = fl4->saddr;
909 keys->addrs.v4addrs.dst = fl4->daddr;
910 keys->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
911 keys->ports.src = fl4->fl4_sport;
912 keys->ports.dst = fl4->fl4_dport;
913 keys->keyid.keyid = fl4->fl4_gre_key;
914 keys->basic.ip_proto = fl4->flowi4_proto;
916 return flow_hash_from_keys(keys);
918 EXPORT_SYMBOL(__get_hash_from_flowi4);
920 static const struct flow_dissector_key flow_keys_dissector_keys[] = {
922 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
923 .offset = offsetof(struct flow_keys, control),
926 .key_id = FLOW_DISSECTOR_KEY_BASIC,
927 .offset = offsetof(struct flow_keys, basic),
930 .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
931 .offset = offsetof(struct flow_keys, addrs.v4addrs),
934 .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
935 .offset = offsetof(struct flow_keys, addrs.v6addrs),
938 .key_id = FLOW_DISSECTOR_KEY_TIPC_ADDRS,
939 .offset = offsetof(struct flow_keys, addrs.tipcaddrs),
942 .key_id = FLOW_DISSECTOR_KEY_PORTS,
943 .offset = offsetof(struct flow_keys, ports),
946 .key_id = FLOW_DISSECTOR_KEY_VLAN,
947 .offset = offsetof(struct flow_keys, vlan),
950 .key_id = FLOW_DISSECTOR_KEY_FLOW_LABEL,
951 .offset = offsetof(struct flow_keys, tags),
954 .key_id = FLOW_DISSECTOR_KEY_GRE_KEYID,
955 .offset = offsetof(struct flow_keys, keyid),
959 static const struct flow_dissector_key flow_keys_dissector_symmetric_keys[] = {
961 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
962 .offset = offsetof(struct flow_keys, control),
965 .key_id = FLOW_DISSECTOR_KEY_BASIC,
966 .offset = offsetof(struct flow_keys, basic),
969 .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
970 .offset = offsetof(struct flow_keys, addrs.v4addrs),
973 .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
974 .offset = offsetof(struct flow_keys, addrs.v6addrs),
977 .key_id = FLOW_DISSECTOR_KEY_PORTS,
978 .offset = offsetof(struct flow_keys, ports),
982 static const struct flow_dissector_key flow_keys_buf_dissector_keys[] = {
984 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
985 .offset = offsetof(struct flow_keys, control),
988 .key_id = FLOW_DISSECTOR_KEY_BASIC,
989 .offset = offsetof(struct flow_keys, basic),
993 struct flow_dissector flow_keys_dissector __read_mostly;
994 EXPORT_SYMBOL(flow_keys_dissector);
996 struct flow_dissector flow_keys_buf_dissector __read_mostly;
998 static int __init init_default_flow_dissectors(void)
1000 skb_flow_dissector_init(&flow_keys_dissector,
1001 flow_keys_dissector_keys,
1002 ARRAY_SIZE(flow_keys_dissector_keys));
1003 skb_flow_dissector_init(&flow_keys_dissector_symmetric,
1004 flow_keys_dissector_symmetric_keys,
1005 ARRAY_SIZE(flow_keys_dissector_symmetric_keys));
1006 skb_flow_dissector_init(&flow_keys_buf_dissector,
1007 flow_keys_buf_dissector_keys,
1008 ARRAY_SIZE(flow_keys_buf_dissector_keys));
1012 core_initcall(init_default_flow_dissectors);