Commit | Line | Data |
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0744dd00 | 1 | #include <linux/skbuff.h> |
c452ed70 | 2 | #include <linux/export.h> |
0744dd00 ED |
3 | #include <linux/ip.h> |
4 | #include <linux/ipv6.h> | |
5 | #include <linux/if_vlan.h> | |
6 | #include <net/ip.h> | |
ddbe5032 | 7 | #include <net/ipv6.h> |
f77668dc DB |
8 | #include <linux/igmp.h> |
9 | #include <linux/icmp.h> | |
10 | #include <linux/sctp.h> | |
11 | #include <linux/dccp.h> | |
0744dd00 ED |
12 | #include <linux/if_tunnel.h> |
13 | #include <linux/if_pppox.h> | |
14 | #include <linux/ppp_defs.h> | |
15 | #include <net/flow_keys.h> | |
16 | ||
4d77d2b5 ED |
17 | /* copy saddr & daddr, possibly using 64bit load/store |
18 | * Equivalent to : flow->src = iph->saddr; | |
19 | * flow->dst = iph->daddr; | |
20 | */ | |
21 | static void iph_to_flow_copy_addrs(struct flow_keys *flow, const struct iphdr *iph) | |
22 | { | |
23 | BUILD_BUG_ON(offsetof(typeof(*flow), dst) != | |
24 | offsetof(typeof(*flow), src) + sizeof(flow->src)); | |
25 | memcpy(&flow->src, &iph->saddr, sizeof(flow->src) + sizeof(flow->dst)); | |
26 | } | |
0744dd00 | 27 | |
357afe9c NA |
28 | /** |
29 | * skb_flow_get_ports - extract the upper layer ports and return them | |
30 | * @skb: buffer to extract the ports from | |
31 | * @thoff: transport header offset | |
32 | * @ip_proto: protocol for which to get port offset | |
33 | * | |
34 | * The function will try to retrieve the ports at offset thoff + poff where poff | |
35 | * is the protocol port offset returned from proto_ports_offset | |
36 | */ | |
37 | __be32 skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto) | |
38 | { | |
39 | int poff = proto_ports_offset(ip_proto); | |
40 | ||
41 | if (poff >= 0) { | |
42 | __be32 *ports, _ports; | |
43 | ||
44 | ports = skb_header_pointer(skb, thoff + poff, | |
45 | sizeof(_ports), &_ports); | |
46 | if (ports) | |
47 | return *ports; | |
48 | } | |
49 | ||
50 | return 0; | |
51 | } | |
52 | EXPORT_SYMBOL(skb_flow_get_ports); | |
53 | ||
0744dd00 ED |
54 | bool skb_flow_dissect(const struct sk_buff *skb, struct flow_keys *flow) |
55 | { | |
357afe9c | 56 | int nhoff = skb_network_offset(skb); |
0744dd00 ED |
57 | u8 ip_proto; |
58 | __be16 proto = skb->protocol; | |
59 | ||
60 | memset(flow, 0, sizeof(*flow)); | |
61 | ||
62 | again: | |
63 | switch (proto) { | |
64 | case __constant_htons(ETH_P_IP): { | |
65 | const struct iphdr *iph; | |
66 | struct iphdr _iph; | |
67 | ip: | |
68 | iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph); | |
6f092343 | 69 | if (!iph || iph->ihl < 5) |
0744dd00 ED |
70 | return false; |
71 | ||
72 | if (ip_is_fragment(iph)) | |
73 | ip_proto = 0; | |
74 | else | |
75 | ip_proto = iph->protocol; | |
4d77d2b5 | 76 | iph_to_flow_copy_addrs(flow, iph); |
0744dd00 ED |
77 | nhoff += iph->ihl * 4; |
78 | break; | |
79 | } | |
80 | case __constant_htons(ETH_P_IPV6): { | |
81 | const struct ipv6hdr *iph; | |
82 | struct ipv6hdr _iph; | |
83 | ipv6: | |
84 | iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph); | |
85 | if (!iph) | |
86 | return false; | |
87 | ||
88 | ip_proto = iph->nexthdr; | |
ddbe5032 ED |
89 | flow->src = (__force __be32)ipv6_addr_hash(&iph->saddr); |
90 | flow->dst = (__force __be32)ipv6_addr_hash(&iph->daddr); | |
0744dd00 ED |
91 | nhoff += sizeof(struct ipv6hdr); |
92 | break; | |
93 | } | |
e11aada3 | 94 | case __constant_htons(ETH_P_8021AD): |
0744dd00 ED |
95 | case __constant_htons(ETH_P_8021Q): { |
96 | const struct vlan_hdr *vlan; | |
97 | struct vlan_hdr _vlan; | |
98 | ||
99 | vlan = skb_header_pointer(skb, nhoff, sizeof(_vlan), &_vlan); | |
100 | if (!vlan) | |
101 | return false; | |
102 | ||
103 | proto = vlan->h_vlan_encapsulated_proto; | |
104 | nhoff += sizeof(*vlan); | |
105 | goto again; | |
106 | } | |
107 | case __constant_htons(ETH_P_PPP_SES): { | |
108 | struct { | |
109 | struct pppoe_hdr hdr; | |
110 | __be16 proto; | |
111 | } *hdr, _hdr; | |
112 | hdr = skb_header_pointer(skb, nhoff, sizeof(_hdr), &_hdr); | |
113 | if (!hdr) | |
114 | return false; | |
115 | proto = hdr->proto; | |
116 | nhoff += PPPOE_SES_HLEN; | |
117 | switch (proto) { | |
118 | case __constant_htons(PPP_IP): | |
119 | goto ip; | |
120 | case __constant_htons(PPP_IPV6): | |
121 | goto ipv6; | |
122 | default: | |
123 | return false; | |
124 | } | |
125 | } | |
126 | default: | |
127 | return false; | |
128 | } | |
129 | ||
130 | switch (ip_proto) { | |
131 | case IPPROTO_GRE: { | |
132 | struct gre_hdr { | |
133 | __be16 flags; | |
134 | __be16 proto; | |
135 | } *hdr, _hdr; | |
136 | ||
137 | hdr = skb_header_pointer(skb, nhoff, sizeof(_hdr), &_hdr); | |
138 | if (!hdr) | |
139 | return false; | |
140 | /* | |
141 | * Only look inside GRE if version zero and no | |
142 | * routing | |
143 | */ | |
144 | if (!(hdr->flags & (GRE_VERSION|GRE_ROUTING))) { | |
145 | proto = hdr->proto; | |
146 | nhoff += 4; | |
147 | if (hdr->flags & GRE_CSUM) | |
148 | nhoff += 4; | |
149 | if (hdr->flags & GRE_KEY) | |
150 | nhoff += 4; | |
151 | if (hdr->flags & GRE_SEQ) | |
152 | nhoff += 4; | |
e1733de2 MD |
153 | if (proto == htons(ETH_P_TEB)) { |
154 | const struct ethhdr *eth; | |
155 | struct ethhdr _eth; | |
156 | ||
157 | eth = skb_header_pointer(skb, nhoff, | |
158 | sizeof(_eth), &_eth); | |
159 | if (!eth) | |
160 | return false; | |
161 | proto = eth->h_proto; | |
162 | nhoff += sizeof(*eth); | |
163 | } | |
0744dd00 ED |
164 | goto again; |
165 | } | |
166 | break; | |
167 | } | |
168 | case IPPROTO_IPIP: | |
fca41895 TH |
169 | proto = htons(ETH_P_IP); |
170 | goto ip; | |
b438f940 TH |
171 | case IPPROTO_IPV6: |
172 | proto = htons(ETH_P_IPV6); | |
173 | goto ipv6; | |
0744dd00 ED |
174 | default: |
175 | break; | |
176 | } | |
177 | ||
178 | flow->ip_proto = ip_proto; | |
357afe9c | 179 | flow->ports = skb_flow_get_ports(skb, nhoff, ip_proto); |
8ed78166 DB |
180 | flow->thoff = (u16) nhoff; |
181 | ||
0744dd00 ED |
182 | return true; |
183 | } | |
184 | EXPORT_SYMBOL(skb_flow_dissect); | |
441d9d32 CW |
185 | |
186 | static u32 hashrnd __read_mostly; | |
66415cf8 HFS |
187 | static __always_inline void __flow_hash_secret_init(void) |
188 | { | |
189 | net_get_random_once(&hashrnd, sizeof(hashrnd)); | |
190 | } | |
191 | ||
192 | static __always_inline u32 __flow_hash_3words(u32 a, u32 b, u32 c) | |
193 | { | |
194 | __flow_hash_secret_init(); | |
195 | return jhash_3words(a, b, c, hashrnd); | |
196 | } | |
197 | ||
198 | static __always_inline u32 __flow_hash_1word(u32 a) | |
199 | { | |
200 | __flow_hash_secret_init(); | |
201 | return jhash_1word(a, hashrnd); | |
202 | } | |
441d9d32 CW |
203 | |
204 | /* | |
205 | * __skb_get_rxhash: calculate a flow hash based on src/dst addresses | |
206 | * and src/dst port numbers. Sets rxhash in skb to non-zero hash value | |
207 | * on success, zero indicates no valid hash. Also, sets l4_rxhash in skb | |
208 | * if hash is a canonical 4-tuple hash over transport ports. | |
209 | */ | |
210 | void __skb_get_rxhash(struct sk_buff *skb) | |
211 | { | |
212 | struct flow_keys keys; | |
213 | u32 hash; | |
214 | ||
215 | if (!skb_flow_dissect(skb, &keys)) | |
216 | return; | |
217 | ||
218 | if (keys.ports) | |
219 | skb->l4_rxhash = 1; | |
220 | ||
221 | /* get a consistent hash (same value on both flow directions) */ | |
222 | if (((__force u32)keys.dst < (__force u32)keys.src) || | |
223 | (((__force u32)keys.dst == (__force u32)keys.src) && | |
224 | ((__force u16)keys.port16[1] < (__force u16)keys.port16[0]))) { | |
225 | swap(keys.dst, keys.src); | |
226 | swap(keys.port16[0], keys.port16[1]); | |
227 | } | |
228 | ||
66415cf8 HFS |
229 | hash = __flow_hash_3words((__force u32)keys.dst, |
230 | (__force u32)keys.src, | |
231 | (__force u32)keys.ports); | |
441d9d32 CW |
232 | if (!hash) |
233 | hash = 1; | |
234 | ||
235 | skb->rxhash = hash; | |
236 | } | |
237 | EXPORT_SYMBOL(__skb_get_rxhash); | |
238 | ||
239 | /* | |
240 | * Returns a Tx hash based on the given packet descriptor a Tx queues' number | |
241 | * to be used as a distribution range. | |
242 | */ | |
243 | u16 __skb_tx_hash(const struct net_device *dev, const struct sk_buff *skb, | |
244 | unsigned int num_tx_queues) | |
245 | { | |
246 | u32 hash; | |
247 | u16 qoffset = 0; | |
248 | u16 qcount = num_tx_queues; | |
249 | ||
250 | if (skb_rx_queue_recorded(skb)) { | |
251 | hash = skb_get_rx_queue(skb); | |
252 | while (unlikely(hash >= num_tx_queues)) | |
253 | hash -= num_tx_queues; | |
254 | return hash; | |
255 | } | |
256 | ||
257 | if (dev->num_tc) { | |
258 | u8 tc = netdev_get_prio_tc_map(dev, skb->priority); | |
259 | qoffset = dev->tc_to_txq[tc].offset; | |
260 | qcount = dev->tc_to_txq[tc].count; | |
261 | } | |
262 | ||
263 | if (skb->sk && skb->sk->sk_hash) | |
264 | hash = skb->sk->sk_hash; | |
265 | else | |
266 | hash = (__force u16) skb->protocol; | |
66415cf8 | 267 | hash = __flow_hash_1word(hash); |
441d9d32 CW |
268 | |
269 | return (u16) (((u64) hash * qcount) >> 32) + qoffset; | |
270 | } | |
271 | EXPORT_SYMBOL(__skb_tx_hash); | |
272 | ||
f77668dc DB |
273 | /* __skb_get_poff() returns the offset to the payload as far as it could |
274 | * be dissected. The main user is currently BPF, so that we can dynamically | |
275 | * truncate packets without needing to push actual payload to the user | |
276 | * space and can analyze headers only, instead. | |
277 | */ | |
278 | u32 __skb_get_poff(const struct sk_buff *skb) | |
279 | { | |
280 | struct flow_keys keys; | |
281 | u32 poff = 0; | |
282 | ||
283 | if (!skb_flow_dissect(skb, &keys)) | |
284 | return 0; | |
285 | ||
286 | poff += keys.thoff; | |
287 | switch (keys.ip_proto) { | |
288 | case IPPROTO_TCP: { | |
289 | const struct tcphdr *tcph; | |
290 | struct tcphdr _tcph; | |
291 | ||
292 | tcph = skb_header_pointer(skb, poff, sizeof(_tcph), &_tcph); | |
293 | if (!tcph) | |
294 | return poff; | |
295 | ||
296 | poff += max_t(u32, sizeof(struct tcphdr), tcph->doff * 4); | |
297 | break; | |
298 | } | |
299 | case IPPROTO_UDP: | |
300 | case IPPROTO_UDPLITE: | |
301 | poff += sizeof(struct udphdr); | |
302 | break; | |
303 | /* For the rest, we do not really care about header | |
304 | * extensions at this point for now. | |
305 | */ | |
306 | case IPPROTO_ICMP: | |
307 | poff += sizeof(struct icmphdr); | |
308 | break; | |
309 | case IPPROTO_ICMPV6: | |
310 | poff += sizeof(struct icmp6hdr); | |
311 | break; | |
312 | case IPPROTO_IGMP: | |
313 | poff += sizeof(struct igmphdr); | |
314 | break; | |
315 | case IPPROTO_DCCP: | |
316 | poff += sizeof(struct dccp_hdr); | |
317 | break; | |
318 | case IPPROTO_SCTP: | |
319 | poff += sizeof(struct sctphdr); | |
320 | break; | |
321 | } | |
322 | ||
323 | return poff; | |
324 | } | |
325 | ||
441d9d32 CW |
326 | static inline u16 dev_cap_txqueue(struct net_device *dev, u16 queue_index) |
327 | { | |
328 | if (unlikely(queue_index >= dev->real_num_tx_queues)) { | |
329 | net_warn_ratelimited("%s selects TX queue %d, but real number of TX queues is %d\n", | |
330 | dev->name, queue_index, | |
331 | dev->real_num_tx_queues); | |
332 | return 0; | |
333 | } | |
334 | return queue_index; | |
335 | } | |
336 | ||
337 | static inline int get_xps_queue(struct net_device *dev, struct sk_buff *skb) | |
338 | { | |
339 | #ifdef CONFIG_XPS | |
340 | struct xps_dev_maps *dev_maps; | |
341 | struct xps_map *map; | |
342 | int queue_index = -1; | |
343 | ||
344 | rcu_read_lock(); | |
345 | dev_maps = rcu_dereference(dev->xps_maps); | |
346 | if (dev_maps) { | |
347 | map = rcu_dereference( | |
348 | dev_maps->cpu_map[raw_smp_processor_id()]); | |
349 | if (map) { | |
350 | if (map->len == 1) | |
351 | queue_index = map->queues[0]; | |
352 | else { | |
353 | u32 hash; | |
354 | if (skb->sk && skb->sk->sk_hash) | |
355 | hash = skb->sk->sk_hash; | |
356 | else | |
357 | hash = (__force u16) skb->protocol ^ | |
358 | skb->rxhash; | |
66415cf8 | 359 | hash = __flow_hash_1word(hash); |
441d9d32 CW |
360 | queue_index = map->queues[ |
361 | ((u64)hash * map->len) >> 32]; | |
362 | } | |
363 | if (unlikely(queue_index >= dev->real_num_tx_queues)) | |
364 | queue_index = -1; | |
365 | } | |
366 | } | |
367 | rcu_read_unlock(); | |
368 | ||
369 | return queue_index; | |
370 | #else | |
371 | return -1; | |
372 | #endif | |
373 | } | |
374 | ||
375 | u16 __netdev_pick_tx(struct net_device *dev, struct sk_buff *skb) | |
376 | { | |
377 | struct sock *sk = skb->sk; | |
378 | int queue_index = sk_tx_queue_get(sk); | |
379 | ||
380 | if (queue_index < 0 || skb->ooo_okay || | |
381 | queue_index >= dev->real_num_tx_queues) { | |
382 | int new_index = get_xps_queue(dev, skb); | |
383 | if (new_index < 0) | |
384 | new_index = skb_tx_hash(dev, skb); | |
385 | ||
702821f4 ED |
386 | if (queue_index != new_index && sk && |
387 | rcu_access_pointer(sk->sk_dst_cache)) | |
50d1784e | 388 | sk_tx_queue_set(sk, new_index); |
441d9d32 CW |
389 | |
390 | queue_index = new_index; | |
391 | } | |
392 | ||
393 | return queue_index; | |
394 | } | |
395 | EXPORT_SYMBOL(__netdev_pick_tx); | |
396 | ||
397 | struct netdev_queue *netdev_pick_tx(struct net_device *dev, | |
398 | struct sk_buff *skb) | |
399 | { | |
400 | int queue_index = 0; | |
401 | ||
402 | if (dev->real_num_tx_queues != 1) { | |
403 | const struct net_device_ops *ops = dev->netdev_ops; | |
404 | if (ops->ndo_select_queue) | |
405 | queue_index = ops->ndo_select_queue(dev, skb); | |
406 | else | |
407 | queue_index = __netdev_pick_tx(dev, skb); | |
408 | queue_index = dev_cap_txqueue(dev, queue_index); | |
409 | } | |
410 | ||
411 | skb_set_queue_mapping(skb, queue_index); | |
412 | return netdev_get_tx_queue(dev, queue_index); | |
413 | } |