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