Commit | Line | Data |
---|---|---|
fbff949e | 1 | #include <linux/kernel.h> |
0744dd00 | 2 | #include <linux/skbuff.h> |
c452ed70 | 3 | #include <linux/export.h> |
0744dd00 ED |
4 | #include <linux/ip.h> |
5 | #include <linux/ipv6.h> | |
6 | #include <linux/if_vlan.h> | |
7 | #include <net/ip.h> | |
ddbe5032 | 8 | #include <net/ipv6.h> |
f77668dc DB |
9 | #include <linux/igmp.h> |
10 | #include <linux/icmp.h> | |
11 | #include <linux/sctp.h> | |
12 | #include <linux/dccp.h> | |
0744dd00 ED |
13 | #include <linux/if_tunnel.h> |
14 | #include <linux/if_pppox.h> | |
15 | #include <linux/ppp_defs.h> | |
06635a35 | 16 | #include <linux/stddef.h> |
67a900cc | 17 | #include <linux/if_ether.h> |
1bd758eb | 18 | #include <net/flow_dissector.h> |
56193d1b | 19 | #include <scsi/fc/fc_fcoe.h> |
0744dd00 | 20 | |
fbff949e JP |
21 | static bool skb_flow_dissector_uses_key(struct flow_dissector *flow_dissector, |
22 | enum flow_dissector_key_id key_id) | |
23 | { | |
24 | return flow_dissector->used_keys & (1 << key_id); | |
25 | } | |
26 | ||
27 | static void skb_flow_dissector_set_key(struct flow_dissector *flow_dissector, | |
28 | enum flow_dissector_key_id key_id) | |
29 | { | |
30 | flow_dissector->used_keys |= (1 << key_id); | |
31 | } | |
32 | ||
33 | static void *skb_flow_dissector_target(struct flow_dissector *flow_dissector, | |
34 | enum flow_dissector_key_id key_id, | |
35 | void *target_container) | |
36 | { | |
37 | return ((char *) target_container) + flow_dissector->offset[key_id]; | |
38 | } | |
39 | ||
40 | void skb_flow_dissector_init(struct flow_dissector *flow_dissector, | |
41 | const struct flow_dissector_key *key, | |
42 | unsigned int key_count) | |
43 | { | |
44 | unsigned int i; | |
45 | ||
46 | memset(flow_dissector, 0, sizeof(*flow_dissector)); | |
47 | ||
48 | for (i = 0; i < key_count; i++, key++) { | |
49 | /* User should make sure that every key target offset is withing | |
50 | * boundaries of unsigned short. | |
51 | */ | |
52 | BUG_ON(key->offset > USHRT_MAX); | |
53 | BUG_ON(skb_flow_dissector_uses_key(flow_dissector, | |
54 | key->key_id)); | |
55 | ||
56 | skb_flow_dissector_set_key(flow_dissector, key->key_id); | |
57 | flow_dissector->offset[key->key_id] = key->offset; | |
58 | } | |
59 | ||
60 | /* Ensure that the dissector always includes basic key. That way | |
61 | * we are able to avoid handling lack of it in fast path. | |
62 | */ | |
63 | BUG_ON(!skb_flow_dissector_uses_key(flow_dissector, | |
64 | FLOW_DISSECTOR_KEY_BASIC)); | |
65 | } | |
66 | EXPORT_SYMBOL(skb_flow_dissector_init); | |
67 | ||
357afe9c | 68 | /** |
6451b3f5 WC |
69 | * __skb_flow_get_ports - extract the upper layer ports and return them |
70 | * @skb: sk_buff to extract the ports from | |
357afe9c NA |
71 | * @thoff: transport header offset |
72 | * @ip_proto: protocol for which to get port offset | |
6451b3f5 WC |
73 | * @data: raw buffer pointer to the packet, if NULL use skb->data |
74 | * @hlen: packet header length, if @data is NULL use skb_headlen(skb) | |
357afe9c NA |
75 | * |
76 | * The function will try to retrieve the ports at offset thoff + poff where poff | |
77 | * is the protocol port offset returned from proto_ports_offset | |
78 | */ | |
690e36e7 DM |
79 | __be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto, |
80 | void *data, int hlen) | |
357afe9c NA |
81 | { |
82 | int poff = proto_ports_offset(ip_proto); | |
83 | ||
690e36e7 DM |
84 | if (!data) { |
85 | data = skb->data; | |
86 | hlen = skb_headlen(skb); | |
87 | } | |
88 | ||
357afe9c NA |
89 | if (poff >= 0) { |
90 | __be32 *ports, _ports; | |
91 | ||
690e36e7 DM |
92 | ports = __skb_header_pointer(skb, thoff + poff, |
93 | sizeof(_ports), data, hlen, &_ports); | |
357afe9c NA |
94 | if (ports) |
95 | return *ports; | |
96 | } | |
97 | ||
98 | return 0; | |
99 | } | |
690e36e7 | 100 | EXPORT_SYMBOL(__skb_flow_get_ports); |
357afe9c | 101 | |
453a940e WC |
102 | /** |
103 | * __skb_flow_dissect - extract the flow_keys struct and return it | |
104 | * @skb: sk_buff to extract the flow from, can be NULL if the rest are specified | |
06635a35 JP |
105 | * @flow_dissector: list of keys to dissect |
106 | * @target_container: target structure to put dissected values into | |
453a940e WC |
107 | * @data: raw buffer pointer to the packet, if NULL use skb->data |
108 | * @proto: protocol for which to get the flow, if @data is NULL use skb->protocol | |
109 | * @nhoff: network header offset, if @data is NULL use skb_network_offset(skb) | |
110 | * @hlen: packet header length, if @data is NULL use skb_headlen(skb) | |
111 | * | |
06635a35 JP |
112 | * The function will try to retrieve individual keys into target specified |
113 | * by flow_dissector from either the skbuff or a raw buffer specified by the | |
114 | * rest parameters. | |
115 | * | |
116 | * Caller must take care of zeroing target container memory. | |
453a940e | 117 | */ |
06635a35 JP |
118 | bool __skb_flow_dissect(const struct sk_buff *skb, |
119 | struct flow_dissector *flow_dissector, | |
120 | void *target_container, | |
453a940e | 121 | void *data, __be16 proto, int nhoff, int hlen) |
0744dd00 | 122 | { |
06635a35 JP |
123 | struct flow_dissector_key_basic *key_basic; |
124 | struct flow_dissector_key_addrs *key_addrs; | |
125 | struct flow_dissector_key_ports *key_ports; | |
0744dd00 | 126 | u8 ip_proto; |
0744dd00 | 127 | |
690e36e7 DM |
128 | if (!data) { |
129 | data = skb->data; | |
453a940e WC |
130 | proto = skb->protocol; |
131 | nhoff = skb_network_offset(skb); | |
690e36e7 DM |
132 | hlen = skb_headlen(skb); |
133 | } | |
134 | ||
06635a35 JP |
135 | /* It is ensured by skb_flow_dissector_init() that basic key will |
136 | * be always present. | |
137 | */ | |
138 | key_basic = skb_flow_dissector_target(flow_dissector, | |
139 | FLOW_DISSECTOR_KEY_BASIC, | |
140 | target_container); | |
0744dd00 | 141 | |
67a900cc JP |
142 | if (skb_flow_dissector_uses_key(flow_dissector, |
143 | FLOW_DISSECTOR_KEY_ETH_ADDRS)) { | |
144 | struct ethhdr *eth = eth_hdr(skb); | |
145 | struct flow_dissector_key_eth_addrs *key_eth_addrs; | |
146 | ||
147 | key_eth_addrs = skb_flow_dissector_target(flow_dissector, | |
148 | FLOW_DISSECTOR_KEY_ETH_ADDRS, | |
149 | target_container); | |
150 | memcpy(key_eth_addrs, ð->h_dest, sizeof(*key_eth_addrs)); | |
151 | } | |
152 | ||
0744dd00 ED |
153 | again: |
154 | switch (proto) { | |
2b8837ae | 155 | case htons(ETH_P_IP): { |
0744dd00 ED |
156 | const struct iphdr *iph; |
157 | struct iphdr _iph; | |
158 | ip: | |
690e36e7 | 159 | iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph); |
6f092343 | 160 | if (!iph || iph->ihl < 5) |
0744dd00 | 161 | return false; |
3797d3e8 | 162 | nhoff += iph->ihl * 4; |
0744dd00 | 163 | |
3797d3e8 | 164 | ip_proto = iph->protocol; |
0744dd00 ED |
165 | if (ip_is_fragment(iph)) |
166 | ip_proto = 0; | |
3797d3e8 | 167 | |
06635a35 JP |
168 | if (!skb_flow_dissector_uses_key(flow_dissector, |
169 | FLOW_DISSECTOR_KEY_IPV4_ADDRS)) | |
5af7fb6e | 170 | break; |
06635a35 JP |
171 | key_addrs = skb_flow_dissector_target(flow_dissector, |
172 | FLOW_DISSECTOR_KEY_IPV4_ADDRS, | |
173 | target_container); | |
174 | memcpy(key_addrs, &iph->saddr, sizeof(*key_addrs)); | |
0744dd00 ED |
175 | break; |
176 | } | |
2b8837ae | 177 | case htons(ETH_P_IPV6): { |
0744dd00 ED |
178 | const struct ipv6hdr *iph; |
179 | struct ipv6hdr _iph; | |
19469a87 TH |
180 | __be32 flow_label; |
181 | ||
0744dd00 | 182 | ipv6: |
690e36e7 | 183 | iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph); |
0744dd00 ED |
184 | if (!iph) |
185 | return false; | |
186 | ||
187 | ip_proto = iph->nexthdr; | |
0744dd00 | 188 | nhoff += sizeof(struct ipv6hdr); |
19469a87 | 189 | |
b924933c JP |
190 | if (skb_flow_dissector_uses_key(flow_dissector, |
191 | FLOW_DISSECTOR_KEY_IPV6_HASH_ADDRS)) { | |
192 | key_addrs = skb_flow_dissector_target(flow_dissector, | |
193 | FLOW_DISSECTOR_KEY_IPV6_HASH_ADDRS, | |
194 | target_container); | |
56193d1b | 195 | |
b924933c JP |
196 | key_addrs->src = (__force __be32)ipv6_addr_hash(&iph->saddr); |
197 | key_addrs->dst = (__force __be32)ipv6_addr_hash(&iph->daddr); | |
198 | goto flow_label; | |
199 | } | |
200 | if (skb_flow_dissector_uses_key(flow_dissector, | |
201 | FLOW_DISSECTOR_KEY_IPV6_ADDRS)) { | |
202 | struct flow_dissector_key_ipv6_addrs *key_ipv6_addrs; | |
203 | ||
204 | key_ipv6_addrs = skb_flow_dissector_target(flow_dissector, | |
205 | FLOW_DISSECTOR_KEY_IPV6_ADDRS, | |
206 | target_container); | |
5af7fb6e | 207 | |
b924933c JP |
208 | memcpy(key_ipv6_addrs, &iph->saddr, sizeof(*key_ipv6_addrs)); |
209 | goto flow_label; | |
210 | } | |
211 | break; | |
212 | flow_label: | |
19469a87 TH |
213 | flow_label = ip6_flowlabel(iph); |
214 | if (flow_label) { | |
215 | /* Awesome, IPv6 packet has a flow label so we can | |
216 | * use that to represent the ports without any | |
217 | * further dissection. | |
218 | */ | |
06635a35 JP |
219 | |
220 | key_basic->n_proto = proto; | |
221 | key_basic->ip_proto = ip_proto; | |
222 | key_basic->thoff = (u16)nhoff; | |
223 | ||
12c227ec JP |
224 | if (skb_flow_dissector_uses_key(flow_dissector, |
225 | FLOW_DISSECTOR_KEY_PORTS)) { | |
226 | key_ports = skb_flow_dissector_target(flow_dissector, | |
227 | FLOW_DISSECTOR_KEY_PORTS, | |
228 | target_container); | |
229 | key_ports->ports = flow_label; | |
230 | } | |
19469a87 TH |
231 | |
232 | return true; | |
233 | } | |
234 | ||
0744dd00 ED |
235 | break; |
236 | } | |
2b8837ae JP |
237 | case htons(ETH_P_8021AD): |
238 | case htons(ETH_P_8021Q): { | |
0744dd00 ED |
239 | const struct vlan_hdr *vlan; |
240 | struct vlan_hdr _vlan; | |
241 | ||
690e36e7 | 242 | vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan), data, hlen, &_vlan); |
0744dd00 ED |
243 | if (!vlan) |
244 | return false; | |
245 | ||
246 | proto = vlan->h_vlan_encapsulated_proto; | |
247 | nhoff += sizeof(*vlan); | |
248 | goto again; | |
249 | } | |
2b8837ae | 250 | case htons(ETH_P_PPP_SES): { |
0744dd00 ED |
251 | struct { |
252 | struct pppoe_hdr hdr; | |
253 | __be16 proto; | |
254 | } *hdr, _hdr; | |
690e36e7 | 255 | hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr); |
0744dd00 ED |
256 | if (!hdr) |
257 | return false; | |
258 | proto = hdr->proto; | |
259 | nhoff += PPPOE_SES_HLEN; | |
260 | switch (proto) { | |
2b8837ae | 261 | case htons(PPP_IP): |
0744dd00 | 262 | goto ip; |
2b8837ae | 263 | case htons(PPP_IPV6): |
0744dd00 ED |
264 | goto ipv6; |
265 | default: | |
266 | return false; | |
267 | } | |
268 | } | |
08bfc9cb EH |
269 | case htons(ETH_P_TIPC): { |
270 | struct { | |
271 | __be32 pre[3]; | |
272 | __be32 srcnode; | |
273 | } *hdr, _hdr; | |
274 | hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr); | |
275 | if (!hdr) | |
276 | return false; | |
06635a35 JP |
277 | key_basic->n_proto = proto; |
278 | key_basic->thoff = (u16)nhoff; | |
279 | ||
280 | if (skb_flow_dissector_uses_key(flow_dissector, | |
281 | FLOW_DISSECTOR_KEY_IPV6_HASH_ADDRS)) { | |
06635a35 JP |
282 | key_addrs = skb_flow_dissector_target(flow_dissector, |
283 | FLOW_DISSECTOR_KEY_IPV6_HASH_ADDRS, | |
284 | target_container); | |
285 | key_addrs->src = hdr->srcnode; | |
286 | key_addrs->dst = 0; | |
287 | } | |
08bfc9cb EH |
288 | return true; |
289 | } | |
56193d1b | 290 | case htons(ETH_P_FCOE): |
06635a35 | 291 | key_basic->thoff = (u16)(nhoff + FCOE_HEADER_LEN); |
56193d1b | 292 | /* fall through */ |
0744dd00 ED |
293 | default: |
294 | return false; | |
295 | } | |
296 | ||
297 | switch (ip_proto) { | |
298 | case IPPROTO_GRE: { | |
299 | struct gre_hdr { | |
300 | __be16 flags; | |
301 | __be16 proto; | |
302 | } *hdr, _hdr; | |
303 | ||
690e36e7 | 304 | hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr); |
0744dd00 ED |
305 | if (!hdr) |
306 | return false; | |
307 | /* | |
308 | * Only look inside GRE if version zero and no | |
309 | * routing | |
310 | */ | |
311 | if (!(hdr->flags & (GRE_VERSION|GRE_ROUTING))) { | |
312 | proto = hdr->proto; | |
313 | nhoff += 4; | |
314 | if (hdr->flags & GRE_CSUM) | |
315 | nhoff += 4; | |
316 | if (hdr->flags & GRE_KEY) | |
317 | nhoff += 4; | |
318 | if (hdr->flags & GRE_SEQ) | |
319 | nhoff += 4; | |
e1733de2 MD |
320 | if (proto == htons(ETH_P_TEB)) { |
321 | const struct ethhdr *eth; | |
322 | struct ethhdr _eth; | |
323 | ||
690e36e7 DM |
324 | eth = __skb_header_pointer(skb, nhoff, |
325 | sizeof(_eth), | |
326 | data, hlen, &_eth); | |
e1733de2 MD |
327 | if (!eth) |
328 | return false; | |
329 | proto = eth->h_proto; | |
330 | nhoff += sizeof(*eth); | |
331 | } | |
0744dd00 ED |
332 | goto again; |
333 | } | |
334 | break; | |
335 | } | |
336 | case IPPROTO_IPIP: | |
fca41895 TH |
337 | proto = htons(ETH_P_IP); |
338 | goto ip; | |
b438f940 TH |
339 | case IPPROTO_IPV6: |
340 | proto = htons(ETH_P_IPV6); | |
341 | goto ipv6; | |
0744dd00 ED |
342 | default: |
343 | break; | |
344 | } | |
345 | ||
06635a35 JP |
346 | /* It is ensured by skb_flow_dissector_init() that basic key will |
347 | * be always present. | |
348 | */ | |
349 | key_basic = skb_flow_dissector_target(flow_dissector, | |
350 | FLOW_DISSECTOR_KEY_BASIC, | |
351 | target_container); | |
352 | key_basic->n_proto = proto; | |
353 | key_basic->ip_proto = ip_proto; | |
354 | key_basic->thoff = (u16) nhoff; | |
355 | ||
356 | if (skb_flow_dissector_uses_key(flow_dissector, | |
357 | FLOW_DISSECTOR_KEY_PORTS)) { | |
358 | key_ports = skb_flow_dissector_target(flow_dissector, | |
359 | FLOW_DISSECTOR_KEY_PORTS, | |
360 | target_container); | |
361 | key_ports->ports = __skb_flow_get_ports(skb, nhoff, ip_proto, | |
362 | data, hlen); | |
363 | } | |
5af7fb6e | 364 | |
0744dd00 ED |
365 | return true; |
366 | } | |
690e36e7 | 367 | EXPORT_SYMBOL(__skb_flow_dissect); |
441d9d32 CW |
368 | |
369 | static u32 hashrnd __read_mostly; | |
66415cf8 HFS |
370 | static __always_inline void __flow_hash_secret_init(void) |
371 | { | |
372 | net_get_random_once(&hashrnd, sizeof(hashrnd)); | |
373 | } | |
374 | ||
50fb7992 | 375 | static __always_inline u32 __flow_hash_3words(u32 a, u32 b, u32 c, u32 keyval) |
66415cf8 | 376 | { |
50fb7992 | 377 | return jhash_3words(a, b, c, keyval); |
66415cf8 HFS |
378 | } |
379 | ||
50fb7992 | 380 | static inline u32 __flow_hash_from_keys(struct flow_keys *keys, u32 keyval) |
5ed20a68 TH |
381 | { |
382 | u32 hash; | |
383 | ||
384 | /* get a consistent hash (same value on both flow directions) */ | |
06635a35 JP |
385 | if (((__force u32)keys->addrs.dst < (__force u32)keys->addrs.src) || |
386 | (((__force u32)keys->addrs.dst == (__force u32)keys->addrs.src) && | |
59346afe | 387 | ((__force u16)keys->ports.dst < (__force u16)keys->ports.src))) { |
06635a35 | 388 | swap(keys->addrs.dst, keys->addrs.src); |
59346afe | 389 | swap(keys->ports.src, keys->ports.dst); |
5ed20a68 TH |
390 | } |
391 | ||
06635a35 JP |
392 | hash = __flow_hash_3words((__force u32)keys->addrs.dst, |
393 | (__force u32)keys->addrs.src, | |
394 | (__force u32)keys->ports.ports, | |
50fb7992 | 395 | keyval); |
5ed20a68 TH |
396 | if (!hash) |
397 | hash = 1; | |
398 | ||
399 | return hash; | |
400 | } | |
401 | ||
402 | u32 flow_hash_from_keys(struct flow_keys *keys) | |
403 | { | |
50fb7992 TH |
404 | __flow_hash_secret_init(); |
405 | return __flow_hash_from_keys(keys, hashrnd); | |
5ed20a68 TH |
406 | } |
407 | EXPORT_SYMBOL(flow_hash_from_keys); | |
408 | ||
50fb7992 TH |
409 | static inline u32 ___skb_get_hash(const struct sk_buff *skb, |
410 | struct flow_keys *keys, u32 keyval) | |
411 | { | |
06635a35 | 412 | if (!skb_flow_dissect_flow_keys(skb, keys)) |
50fb7992 TH |
413 | return 0; |
414 | ||
415 | return __flow_hash_from_keys(keys, keyval); | |
416 | } | |
417 | ||
2f59e1eb TH |
418 | struct _flow_keys_digest_data { |
419 | __be16 n_proto; | |
420 | u8 ip_proto; | |
421 | u8 padding; | |
422 | __be32 ports; | |
423 | __be32 src; | |
424 | __be32 dst; | |
425 | }; | |
426 | ||
427 | void make_flow_keys_digest(struct flow_keys_digest *digest, | |
428 | const struct flow_keys *flow) | |
429 | { | |
430 | struct _flow_keys_digest_data *data = | |
431 | (struct _flow_keys_digest_data *)digest; | |
432 | ||
433 | BUILD_BUG_ON(sizeof(*data) > sizeof(*digest)); | |
434 | ||
435 | memset(digest, 0, sizeof(*digest)); | |
436 | ||
06635a35 JP |
437 | data->n_proto = flow->basic.n_proto; |
438 | data->ip_proto = flow->basic.ip_proto; | |
439 | data->ports = flow->ports.ports; | |
440 | data->src = flow->addrs.src; | |
441 | data->dst = flow->addrs.dst; | |
2f59e1eb TH |
442 | } |
443 | EXPORT_SYMBOL(make_flow_keys_digest); | |
444 | ||
d4fd3275 JP |
445 | /** |
446 | * __skb_get_hash: calculate a flow hash | |
447 | * @skb: sk_buff to calculate flow hash from | |
448 | * | |
449 | * This function calculates a flow hash based on src/dst addresses | |
61b905da TH |
450 | * and src/dst port numbers. Sets hash in skb to non-zero hash value |
451 | * on success, zero indicates no valid hash. Also, sets l4_hash in skb | |
441d9d32 CW |
452 | * if hash is a canonical 4-tuple hash over transport ports. |
453 | */ | |
3958afa1 | 454 | void __skb_get_hash(struct sk_buff *skb) |
441d9d32 CW |
455 | { |
456 | struct flow_keys keys; | |
50fb7992 | 457 | u32 hash; |
441d9d32 | 458 | |
50fb7992 TH |
459 | __flow_hash_secret_init(); |
460 | ||
461 | hash = ___skb_get_hash(skb, &keys, hashrnd); | |
462 | if (!hash) | |
441d9d32 | 463 | return; |
06635a35 | 464 | if (keys.ports.ports) |
61b905da | 465 | skb->l4_hash = 1; |
a3b18ddb | 466 | skb->sw_hash = 1; |
50fb7992 | 467 | skb->hash = hash; |
441d9d32 | 468 | } |
3958afa1 | 469 | EXPORT_SYMBOL(__skb_get_hash); |
441d9d32 | 470 | |
50fb7992 TH |
471 | __u32 skb_get_hash_perturb(const struct sk_buff *skb, u32 perturb) |
472 | { | |
473 | struct flow_keys keys; | |
474 | ||
475 | return ___skb_get_hash(skb, &keys, perturb); | |
476 | } | |
477 | EXPORT_SYMBOL(skb_get_hash_perturb); | |
478 | ||
56193d1b AD |
479 | u32 __skb_get_poff(const struct sk_buff *skb, void *data, |
480 | const struct flow_keys *keys, int hlen) | |
f77668dc | 481 | { |
06635a35 | 482 | u32 poff = keys->basic.thoff; |
f77668dc | 483 | |
06635a35 | 484 | switch (keys->basic.ip_proto) { |
f77668dc | 485 | case IPPROTO_TCP: { |
5af7fb6e AD |
486 | /* access doff as u8 to avoid unaligned access */ |
487 | const u8 *doff; | |
488 | u8 _doff; | |
f77668dc | 489 | |
5af7fb6e AD |
490 | doff = __skb_header_pointer(skb, poff + 12, sizeof(_doff), |
491 | data, hlen, &_doff); | |
492 | if (!doff) | |
f77668dc DB |
493 | return poff; |
494 | ||
5af7fb6e | 495 | poff += max_t(u32, sizeof(struct tcphdr), (*doff & 0xF0) >> 2); |
f77668dc DB |
496 | break; |
497 | } | |
498 | case IPPROTO_UDP: | |
499 | case IPPROTO_UDPLITE: | |
500 | poff += sizeof(struct udphdr); | |
501 | break; | |
502 | /* For the rest, we do not really care about header | |
503 | * extensions at this point for now. | |
504 | */ | |
505 | case IPPROTO_ICMP: | |
506 | poff += sizeof(struct icmphdr); | |
507 | break; | |
508 | case IPPROTO_ICMPV6: | |
509 | poff += sizeof(struct icmp6hdr); | |
510 | break; | |
511 | case IPPROTO_IGMP: | |
512 | poff += sizeof(struct igmphdr); | |
513 | break; | |
514 | case IPPROTO_DCCP: | |
515 | poff += sizeof(struct dccp_hdr); | |
516 | break; | |
517 | case IPPROTO_SCTP: | |
518 | poff += sizeof(struct sctphdr); | |
519 | break; | |
520 | } | |
521 | ||
522 | return poff; | |
523 | } | |
524 | ||
0db89b8b JP |
525 | /** |
526 | * skb_get_poff - get the offset to the payload | |
527 | * @skb: sk_buff to get the payload offset from | |
528 | * | |
529 | * The function will get the offset to the payload as far as it could | |
530 | * be dissected. The main user is currently BPF, so that we can dynamically | |
56193d1b AD |
531 | * truncate packets without needing to push actual payload to the user |
532 | * space and can analyze headers only, instead. | |
533 | */ | |
534 | u32 skb_get_poff(const struct sk_buff *skb) | |
535 | { | |
536 | struct flow_keys keys; | |
537 | ||
06635a35 | 538 | if (!skb_flow_dissect_flow_keys(skb, &keys)) |
56193d1b AD |
539 | return 0; |
540 | ||
541 | return __skb_get_poff(skb, skb->data, &keys, skb_headlen(skb)); | |
542 | } | |
06635a35 JP |
543 | |
544 | static const struct flow_dissector_key flow_keys_dissector_keys[] = { | |
545 | { | |
546 | .key_id = FLOW_DISSECTOR_KEY_BASIC, | |
547 | .offset = offsetof(struct flow_keys, basic), | |
548 | }, | |
549 | { | |
550 | .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS, | |
551 | .offset = offsetof(struct flow_keys, addrs), | |
552 | }, | |
553 | { | |
554 | .key_id = FLOW_DISSECTOR_KEY_IPV6_HASH_ADDRS, | |
555 | .offset = offsetof(struct flow_keys, addrs), | |
556 | }, | |
557 | { | |
558 | .key_id = FLOW_DISSECTOR_KEY_PORTS, | |
559 | .offset = offsetof(struct flow_keys, ports), | |
560 | }, | |
561 | }; | |
562 | ||
563 | static const struct flow_dissector_key flow_keys_buf_dissector_keys[] = { | |
564 | { | |
565 | .key_id = FLOW_DISSECTOR_KEY_BASIC, | |
566 | .offset = offsetof(struct flow_keys, basic), | |
567 | }, | |
568 | }; | |
569 | ||
570 | struct flow_dissector flow_keys_dissector __read_mostly; | |
571 | EXPORT_SYMBOL(flow_keys_dissector); | |
572 | ||
573 | struct flow_dissector flow_keys_buf_dissector __read_mostly; | |
574 | ||
575 | static int __init init_default_flow_dissectors(void) | |
576 | { | |
577 | skb_flow_dissector_init(&flow_keys_dissector, | |
578 | flow_keys_dissector_keys, | |
579 | ARRAY_SIZE(flow_keys_dissector_keys)); | |
580 | skb_flow_dissector_init(&flow_keys_buf_dissector, | |
581 | flow_keys_buf_dissector_keys, | |
582 | ARRAY_SIZE(flow_keys_buf_dissector_keys)); | |
583 | return 0; | |
584 | } | |
585 | ||
586 | late_initcall_sync(init_default_flow_dissectors); |