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, &iph->saddr,
180 sizeof(key_addrs->v4addrs));
181 key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
184 if (ip_is_fragment(iph)) {
185 key_control->flags |= FLOW_DIS_IS_FRAGMENT;
187 if (iph->frag_off & htons(IP_OFFSET)) {
190 key_control->flags |= FLOW_DIS_FIRST_FRAG;
191 if (!(flags & FLOW_DISSECTOR_F_PARSE_1ST_FRAG))
196 if (flags & FLOW_DISSECTOR_F_STOP_AT_L3)
201 case htons(ETH_P_IPV6): {
202 const struct ipv6hdr *iph;
206 iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
210 ip_proto = iph->nexthdr;
211 nhoff += sizeof(struct ipv6hdr);
213 if (dissector_uses_key(flow_dissector,
214 FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
215 key_addrs = skb_flow_dissector_target(flow_dissector,
216 FLOW_DISSECTOR_KEY_IPV6_ADDRS,
219 memcpy(&key_addrs->v6addrs, &iph->saddr,
220 sizeof(key_addrs->v6addrs));
221 key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
224 if ((dissector_uses_key(flow_dissector,
225 FLOW_DISSECTOR_KEY_FLOW_LABEL) ||
226 (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL)) &&
227 ip6_flowlabel(iph)) {
228 __be32 flow_label = ip6_flowlabel(iph);
230 if (dissector_uses_key(flow_dissector,
231 FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
232 key_tags = skb_flow_dissector_target(flow_dissector,
233 FLOW_DISSECTOR_KEY_FLOW_LABEL,
235 key_tags->flow_label = ntohl(flow_label);
237 if (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL)
241 if (flags & FLOW_DISSECTOR_F_STOP_AT_L3)
246 case htons(ETH_P_8021AD):
247 case htons(ETH_P_8021Q): {
248 const struct vlan_hdr *vlan;
249 struct vlan_hdr _vlan;
250 bool vlan_tag_present = skb && skb_vlan_tag_present(skb);
252 if (vlan_tag_present)
253 proto = skb->protocol;
255 if (!vlan_tag_present || eth_type_vlan(skb->protocol)) {
256 vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan),
260 proto = vlan->h_vlan_encapsulated_proto;
261 nhoff += sizeof(*vlan);
267 if (dissector_uses_key(flow_dissector,
268 FLOW_DISSECTOR_KEY_VLAN)) {
269 key_vlan = skb_flow_dissector_target(flow_dissector,
270 FLOW_DISSECTOR_KEY_VLAN,
273 if (vlan_tag_present) {
274 key_vlan->vlan_id = skb_vlan_tag_get_id(skb);
275 key_vlan->vlan_priority =
276 (skb_vlan_tag_get_prio(skb) >> VLAN_PRIO_SHIFT);
278 key_vlan->vlan_id = ntohs(vlan->h_vlan_TCI) &
280 key_vlan->vlan_priority =
281 (ntohs(vlan->h_vlan_TCI) &
282 VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
288 case htons(ETH_P_PPP_SES): {
290 struct pppoe_hdr hdr;
293 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
297 nhoff += PPPOE_SES_HLEN;
301 case htons(PPP_IPV6):
307 case htons(ETH_P_TIPC): {
312 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
316 if (dissector_uses_key(flow_dissector,
317 FLOW_DISSECTOR_KEY_TIPC_ADDRS)) {
318 key_addrs = skb_flow_dissector_target(flow_dissector,
319 FLOW_DISSECTOR_KEY_TIPC_ADDRS,
321 key_addrs->tipcaddrs.srcnode = hdr->srcnode;
322 key_control->addr_type = FLOW_DISSECTOR_KEY_TIPC_ADDRS;
327 case htons(ETH_P_MPLS_UC):
328 case htons(ETH_P_MPLS_MC): {
329 struct mpls_label *hdr, _hdr[2];
331 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
336 if ((ntohl(hdr[0].entry) & MPLS_LS_LABEL_MASK) >>
337 MPLS_LS_LABEL_SHIFT == MPLS_LABEL_ENTROPY) {
338 if (dissector_uses_key(flow_dissector,
339 FLOW_DISSECTOR_KEY_MPLS_ENTROPY)) {
340 key_keyid = skb_flow_dissector_target(flow_dissector,
341 FLOW_DISSECTOR_KEY_MPLS_ENTROPY,
343 key_keyid->keyid = hdr[1].entry &
344 htonl(MPLS_LS_LABEL_MASK);
353 case htons(ETH_P_FCOE):
354 if ((hlen - nhoff) < FCOE_HEADER_LEN)
357 nhoff += FCOE_HEADER_LEN;
366 struct gre_base_hdr *hdr, _hdr;
370 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
374 /* Only look inside GRE without routing */
375 if (hdr->flags & GRE_ROUTING)
378 /* Only look inside GRE for version 0 and 1 */
379 gre_ver = ntohs(hdr->flags & GRE_VERSION);
383 proto = hdr->protocol;
385 /* Version1 must be PPTP, and check the flags */
386 if (!(proto == GRE_PROTO_PPP && (hdr->flags & GRE_KEY)))
390 offset += sizeof(struct gre_base_hdr);
392 if (hdr->flags & GRE_CSUM)
393 offset += sizeof(((struct gre_full_hdr *)0)->csum) +
394 sizeof(((struct gre_full_hdr *)0)->reserved1);
396 if (hdr->flags & GRE_KEY) {
400 keyid = __skb_header_pointer(skb, nhoff + offset, sizeof(_keyid),
401 data, hlen, &_keyid);
405 if (dissector_uses_key(flow_dissector,
406 FLOW_DISSECTOR_KEY_GRE_KEYID)) {
407 key_keyid = skb_flow_dissector_target(flow_dissector,
408 FLOW_DISSECTOR_KEY_GRE_KEYID,
411 key_keyid->keyid = *keyid;
413 key_keyid->keyid = *keyid & GRE_PPTP_KEY_MASK;
415 offset += sizeof(((struct gre_full_hdr *)0)->key);
418 if (hdr->flags & GRE_SEQ)
419 offset += sizeof(((struct pptp_gre_header *)0)->seq);
422 if (proto == htons(ETH_P_TEB)) {
423 const struct ethhdr *eth;
426 eth = __skb_header_pointer(skb, nhoff + offset,
431 proto = eth->h_proto;
432 offset += sizeof(*eth);
434 /* Cap headers that we access via pointers at the
435 * end of the Ethernet header as our maximum alignment
436 * at that point is only 2 bytes.
439 hlen = (nhoff + offset);
441 } else { /* version 1, must be PPTP */
442 u8 _ppp_hdr[PPP_HDRLEN];
445 if (hdr->flags & GRE_ACK)
446 offset += sizeof(((struct pptp_gre_header *)0)->ack);
448 ppp_hdr = skb_header_pointer(skb, nhoff + offset,
449 sizeof(_ppp_hdr), _ppp_hdr);
453 switch (PPP_PROTOCOL(ppp_hdr)) {
455 proto = htons(ETH_P_IP);
458 proto = htons(ETH_P_IPV6);
461 /* Could probably catch some more like MPLS */
465 offset += PPP_HDRLEN;
469 key_control->flags |= FLOW_DIS_ENCAPSULATION;
470 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
476 case NEXTHDR_ROUTING:
478 u8 _opthdr[2], *opthdr;
480 if (proto != htons(ETH_P_IPV6))
483 opthdr = __skb_header_pointer(skb, nhoff, sizeof(_opthdr),
484 data, hlen, &_opthdr);
488 ip_proto = opthdr[0];
489 nhoff += (opthdr[1] + 1) << 3;
493 case NEXTHDR_FRAGMENT: {
494 struct frag_hdr _fh, *fh;
496 if (proto != htons(ETH_P_IPV6))
499 fh = __skb_header_pointer(skb, nhoff, sizeof(_fh),
505 key_control->flags |= FLOW_DIS_IS_FRAGMENT;
507 nhoff += sizeof(_fh);
508 ip_proto = fh->nexthdr;
510 if (!(fh->frag_off & htons(IP6_OFFSET))) {
511 key_control->flags |= FLOW_DIS_FIRST_FRAG;
512 if (flags & FLOW_DISSECTOR_F_PARSE_1ST_FRAG)
518 proto = htons(ETH_P_IP);
520 key_control->flags |= FLOW_DIS_ENCAPSULATION;
521 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
526 proto = htons(ETH_P_IPV6);
528 key_control->flags |= FLOW_DIS_ENCAPSULATION;
529 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
534 proto = htons(ETH_P_MPLS_UC);
540 if (dissector_uses_key(flow_dissector,
541 FLOW_DISSECTOR_KEY_PORTS)) {
542 key_ports = skb_flow_dissector_target(flow_dissector,
543 FLOW_DISSECTOR_KEY_PORTS,
545 key_ports->ports = __skb_flow_get_ports(skb, nhoff, ip_proto,
553 key_basic->n_proto = proto;
554 key_basic->ip_proto = ip_proto;
555 key_control->thoff = (u16)nhoff;
559 EXPORT_SYMBOL(__skb_flow_dissect);
561 static u32 hashrnd __read_mostly;
562 static __always_inline void __flow_hash_secret_init(void)
564 net_get_random_once(&hashrnd, sizeof(hashrnd));
567 static __always_inline u32 __flow_hash_words(const u32 *words, u32 length,
570 return jhash2(words, length, keyval);
573 static inline const u32 *flow_keys_hash_start(const struct flow_keys *flow)
575 const void *p = flow;
577 BUILD_BUG_ON(FLOW_KEYS_HASH_OFFSET % sizeof(u32));
578 return (const u32 *)(p + FLOW_KEYS_HASH_OFFSET);
581 static inline size_t flow_keys_hash_length(const struct flow_keys *flow)
583 size_t diff = FLOW_KEYS_HASH_OFFSET + sizeof(flow->addrs);
584 BUILD_BUG_ON((sizeof(*flow) - FLOW_KEYS_HASH_OFFSET) % sizeof(u32));
585 BUILD_BUG_ON(offsetof(typeof(*flow), addrs) !=
586 sizeof(*flow) - sizeof(flow->addrs));
588 switch (flow->control.addr_type) {
589 case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
590 diff -= sizeof(flow->addrs.v4addrs);
592 case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
593 diff -= sizeof(flow->addrs.v6addrs);
595 case FLOW_DISSECTOR_KEY_TIPC_ADDRS:
596 diff -= sizeof(flow->addrs.tipcaddrs);
599 return (sizeof(*flow) - diff) / sizeof(u32);
602 __be32 flow_get_u32_src(const struct flow_keys *flow)
604 switch (flow->control.addr_type) {
605 case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
606 return flow->addrs.v4addrs.src;
607 case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
608 return (__force __be32)ipv6_addr_hash(
609 &flow->addrs.v6addrs.src);
610 case FLOW_DISSECTOR_KEY_TIPC_ADDRS:
611 return flow->addrs.tipcaddrs.srcnode;
616 EXPORT_SYMBOL(flow_get_u32_src);
618 __be32 flow_get_u32_dst(const struct flow_keys *flow)
620 switch (flow->control.addr_type) {
621 case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
622 return flow->addrs.v4addrs.dst;
623 case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
624 return (__force __be32)ipv6_addr_hash(
625 &flow->addrs.v6addrs.dst);
630 EXPORT_SYMBOL(flow_get_u32_dst);
632 static inline void __flow_hash_consistentify(struct flow_keys *keys)
636 switch (keys->control.addr_type) {
637 case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
638 addr_diff = (__force u32)keys->addrs.v4addrs.dst -
639 (__force u32)keys->addrs.v4addrs.src;
640 if ((addr_diff < 0) ||
642 ((__force u16)keys->ports.dst <
643 (__force u16)keys->ports.src))) {
644 swap(keys->addrs.v4addrs.src, keys->addrs.v4addrs.dst);
645 swap(keys->ports.src, keys->ports.dst);
648 case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
649 addr_diff = memcmp(&keys->addrs.v6addrs.dst,
650 &keys->addrs.v6addrs.src,
651 sizeof(keys->addrs.v6addrs.dst));
652 if ((addr_diff < 0) ||
654 ((__force u16)keys->ports.dst <
655 (__force u16)keys->ports.src))) {
656 for (i = 0; i < 4; i++)
657 swap(keys->addrs.v6addrs.src.s6_addr32[i],
658 keys->addrs.v6addrs.dst.s6_addr32[i]);
659 swap(keys->ports.src, keys->ports.dst);
665 static inline u32 __flow_hash_from_keys(struct flow_keys *keys, u32 keyval)
669 __flow_hash_consistentify(keys);
671 hash = __flow_hash_words(flow_keys_hash_start(keys),
672 flow_keys_hash_length(keys), keyval);
679 u32 flow_hash_from_keys(struct flow_keys *keys)
681 __flow_hash_secret_init();
682 return __flow_hash_from_keys(keys, hashrnd);
684 EXPORT_SYMBOL(flow_hash_from_keys);
686 static inline u32 ___skb_get_hash(const struct sk_buff *skb,
687 struct flow_keys *keys, u32 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, u32 perturb)
763 struct flow_keys keys;
765 return ___skb_get_hash(skb, &keys, perturb);
767 EXPORT_SYMBOL(skb_get_hash_perturb);
769 __u32 __skb_get_hash_flowi6(struct sk_buff *skb, const struct flowi6 *fl6)
771 struct flow_keys keys;
773 memset(&keys, 0, sizeof(keys));
775 memcpy(&keys.addrs.v6addrs.src, &fl6->saddr,
776 sizeof(keys.addrs.v6addrs.src));
777 memcpy(&keys.addrs.v6addrs.dst, &fl6->daddr,
778 sizeof(keys.addrs.v6addrs.dst));
779 keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
780 keys.ports.src = fl6->fl6_sport;
781 keys.ports.dst = fl6->fl6_dport;
782 keys.keyid.keyid = fl6->fl6_gre_key;
783 keys.tags.flow_label = (__force u32)fl6->flowlabel;
784 keys.basic.ip_proto = fl6->flowi6_proto;
786 __skb_set_sw_hash(skb, flow_hash_from_keys(&keys),
787 flow_keys_have_l4(&keys));
791 EXPORT_SYMBOL(__skb_get_hash_flowi6);
793 __u32 __skb_get_hash_flowi4(struct sk_buff *skb, const struct flowi4 *fl4)
795 struct flow_keys keys;
797 memset(&keys, 0, sizeof(keys));
799 keys.addrs.v4addrs.src = fl4->saddr;
800 keys.addrs.v4addrs.dst = fl4->daddr;
801 keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
802 keys.ports.src = fl4->fl4_sport;
803 keys.ports.dst = fl4->fl4_dport;
804 keys.keyid.keyid = fl4->fl4_gre_key;
805 keys.basic.ip_proto = fl4->flowi4_proto;
807 __skb_set_sw_hash(skb, flow_hash_from_keys(&keys),
808 flow_keys_have_l4(&keys));
812 EXPORT_SYMBOL(__skb_get_hash_flowi4);
814 u32 __skb_get_poff(const struct sk_buff *skb, void *data,
815 const struct flow_keys *keys, int hlen)
817 u32 poff = keys->control.thoff;
819 /* skip L4 headers for fragments after the first */
820 if ((keys->control.flags & FLOW_DIS_IS_FRAGMENT) &&
821 !(keys->control.flags & FLOW_DIS_FIRST_FRAG))
824 switch (keys->basic.ip_proto) {
826 /* access doff as u8 to avoid unaligned access */
830 doff = __skb_header_pointer(skb, poff + 12, sizeof(_doff),
835 poff += max_t(u32, sizeof(struct tcphdr), (*doff & 0xF0) >> 2);
839 case IPPROTO_UDPLITE:
840 poff += sizeof(struct udphdr);
842 /* For the rest, we do not really care about header
843 * extensions at this point for now.
846 poff += sizeof(struct icmphdr);
849 poff += sizeof(struct icmp6hdr);
852 poff += sizeof(struct igmphdr);
855 poff += sizeof(struct dccp_hdr);
858 poff += sizeof(struct sctphdr);
866 * skb_get_poff - get the offset to the payload
867 * @skb: sk_buff to get the payload offset from
869 * The function will get the offset to the payload as far as it could
870 * be dissected. The main user is currently BPF, so that we can dynamically
871 * truncate packets without needing to push actual payload to the user
872 * space and can analyze headers only, instead.
874 u32 skb_get_poff(const struct sk_buff *skb)
876 struct flow_keys keys;
878 if (!skb_flow_dissect_flow_keys(skb, &keys, 0))
881 return __skb_get_poff(skb, skb->data, &keys, skb_headlen(skb));
884 __u32 __get_hash_from_flowi6(const struct flowi6 *fl6, struct flow_keys *keys)
886 memset(keys, 0, sizeof(*keys));
888 memcpy(&keys->addrs.v6addrs.src, &fl6->saddr,
889 sizeof(keys->addrs.v6addrs.src));
890 memcpy(&keys->addrs.v6addrs.dst, &fl6->daddr,
891 sizeof(keys->addrs.v6addrs.dst));
892 keys->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
893 keys->ports.src = fl6->fl6_sport;
894 keys->ports.dst = fl6->fl6_dport;
895 keys->keyid.keyid = fl6->fl6_gre_key;
896 keys->tags.flow_label = (__force u32)fl6->flowlabel;
897 keys->basic.ip_proto = fl6->flowi6_proto;
899 return flow_hash_from_keys(keys);
901 EXPORT_SYMBOL(__get_hash_from_flowi6);
903 __u32 __get_hash_from_flowi4(const struct flowi4 *fl4, struct flow_keys *keys)
905 memset(keys, 0, sizeof(*keys));
907 keys->addrs.v4addrs.src = fl4->saddr;
908 keys->addrs.v4addrs.dst = fl4->daddr;
909 keys->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
910 keys->ports.src = fl4->fl4_sport;
911 keys->ports.dst = fl4->fl4_dport;
912 keys->keyid.keyid = fl4->fl4_gre_key;
913 keys->basic.ip_proto = fl4->flowi4_proto;
915 return flow_hash_from_keys(keys);
917 EXPORT_SYMBOL(__get_hash_from_flowi4);
919 static const struct flow_dissector_key flow_keys_dissector_keys[] = {
921 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
922 .offset = offsetof(struct flow_keys, control),
925 .key_id = FLOW_DISSECTOR_KEY_BASIC,
926 .offset = offsetof(struct flow_keys, basic),
929 .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
930 .offset = offsetof(struct flow_keys, addrs.v4addrs),
933 .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
934 .offset = offsetof(struct flow_keys, addrs.v6addrs),
937 .key_id = FLOW_DISSECTOR_KEY_TIPC_ADDRS,
938 .offset = offsetof(struct flow_keys, addrs.tipcaddrs),
941 .key_id = FLOW_DISSECTOR_KEY_PORTS,
942 .offset = offsetof(struct flow_keys, ports),
945 .key_id = FLOW_DISSECTOR_KEY_VLAN,
946 .offset = offsetof(struct flow_keys, vlan),
949 .key_id = FLOW_DISSECTOR_KEY_FLOW_LABEL,
950 .offset = offsetof(struct flow_keys, tags),
953 .key_id = FLOW_DISSECTOR_KEY_GRE_KEYID,
954 .offset = offsetof(struct flow_keys, keyid),
958 static const struct flow_dissector_key flow_keys_dissector_symmetric_keys[] = {
960 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
961 .offset = offsetof(struct flow_keys, control),
964 .key_id = FLOW_DISSECTOR_KEY_BASIC,
965 .offset = offsetof(struct flow_keys, basic),
968 .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
969 .offset = offsetof(struct flow_keys, addrs.v4addrs),
972 .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
973 .offset = offsetof(struct flow_keys, addrs.v6addrs),
976 .key_id = FLOW_DISSECTOR_KEY_PORTS,
977 .offset = offsetof(struct flow_keys, ports),
981 static const struct flow_dissector_key flow_keys_buf_dissector_keys[] = {
983 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
984 .offset = offsetof(struct flow_keys, control),
987 .key_id = FLOW_DISSECTOR_KEY_BASIC,
988 .offset = offsetof(struct flow_keys, basic),
992 struct flow_dissector flow_keys_dissector __read_mostly;
993 EXPORT_SYMBOL(flow_keys_dissector);
995 struct flow_dissector flow_keys_buf_dissector __read_mostly;
997 static int __init init_default_flow_dissectors(void)
999 skb_flow_dissector_init(&flow_keys_dissector,
1000 flow_keys_dissector_keys,
1001 ARRAY_SIZE(flow_keys_dissector_keys));
1002 skb_flow_dissector_init(&flow_keys_dissector_symmetric,
1003 flow_keys_dissector_symmetric_keys,
1004 ARRAY_SIZE(flow_keys_dissector_symmetric_keys));
1005 skb_flow_dissector_init(&flow_keys_buf_dissector,
1006 flow_keys_buf_dissector_keys,
1007 ARRAY_SIZE(flow_keys_buf_dissector_keys));
1011 late_initcall_sync(init_default_flow_dissectors);