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1 /*
2 * Distributed under the terms of the GNU GPL version 2.
3 * Copyright (c) 2007, 2008, 2009, 2010, 2011 Nicira Networks.
4 *
5 * Significant portions of this file may be copied from parts of the Linux
6 * kernel, by Linus Torvalds and others.
7 */
8
9 #include "flow.h"
10 #include "datapath.h"
11 #include <asm/uaccess.h>
12 #include <linux/netdevice.h>
13 #include <linux/etherdevice.h>
14 #include <linux/if_ether.h>
15 #include <linux/if_vlan.h>
16 #include <net/llc_pdu.h>
17 #include <linux/kernel.h>
18 #include <linux/jhash.h>
19 #include <linux/jiffies.h>
20 #include <linux/llc.h>
21 #include <linux/module.h>
22 #include <linux/in.h>
23 #include <linux/rcupdate.h>
24 #include <linux/if_arp.h>
25 #include <linux/if_ether.h>
26 #include <linux/ip.h>
27 #include <linux/ipv6.h>
28 #include <linux/tcp.h>
29 #include <linux/udp.h>
30 #include <linux/icmp.h>
31 #include <linux/icmpv6.h>
32 #include <net/inet_ecn.h>
33 #include <net/ip.h>
34 #include <net/ipv6.h>
35 #include <net/ndisc.h>
36
37 #include "vlan.h"
38
39 static struct kmem_cache *flow_cache;
40 static unsigned int hash_seed __read_mostly;
41
42 static int check_header(struct sk_buff *skb, int len)
43 {
44 if (unlikely(skb->len < len))
45 return -EINVAL;
46 if (unlikely(!pskb_may_pull(skb, len)))
47 return -ENOMEM;
48 return 0;
49 }
50
51 static inline bool arphdr_ok(struct sk_buff *skb)
52 {
53 return pskb_may_pull(skb, skb_network_offset(skb) +
54 sizeof(struct arp_eth_header));
55 }
56
57 static inline int check_iphdr(struct sk_buff *skb)
58 {
59 unsigned int nh_ofs = skb_network_offset(skb);
60 unsigned int ip_len;
61 int err;
62
63 err = check_header(skb, nh_ofs + sizeof(struct iphdr));
64 if (unlikely(err))
65 return err;
66
67 ip_len = ip_hdrlen(skb);
68 if (unlikely(ip_len < sizeof(struct iphdr) ||
69 skb->len < nh_ofs + ip_len))
70 return -EINVAL;
71
72 skb_set_transport_header(skb, nh_ofs + ip_len);
73 return 0;
74 }
75
76 static inline bool tcphdr_ok(struct sk_buff *skb)
77 {
78 int th_ofs = skb_transport_offset(skb);
79 int tcp_len;
80
81 if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
82 return false;
83
84 tcp_len = tcp_hdrlen(skb);
85 if (unlikely(tcp_len < sizeof(struct tcphdr) ||
86 skb->len < th_ofs + tcp_len))
87 return false;
88
89 return true;
90 }
91
92 static inline bool udphdr_ok(struct sk_buff *skb)
93 {
94 return pskb_may_pull(skb, skb_transport_offset(skb) +
95 sizeof(struct udphdr));
96 }
97
98 static inline bool icmphdr_ok(struct sk_buff *skb)
99 {
100 return pskb_may_pull(skb, skb_transport_offset(skb) +
101 sizeof(struct icmphdr));
102 }
103
104 u64 flow_used_time(unsigned long flow_jiffies)
105 {
106 struct timespec cur_ts;
107 u64 cur_ms, idle_ms;
108
109 ktime_get_ts(&cur_ts);
110 idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
111 cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
112 cur_ts.tv_nsec / NSEC_PER_MSEC;
113
114 return cur_ms - idle_ms;
115 }
116
117 #define SW_FLOW_KEY_OFFSET(field) \
118 offsetof(struct sw_flow_key, field) + \
119 FIELD_SIZEOF(struct sw_flow_key, field)
120
121 static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key,
122 int *key_lenp)
123 {
124 unsigned int nh_ofs = skb_network_offset(skb);
125 unsigned int nh_len;
126 int payload_ofs;
127 struct ipv6hdr *nh;
128 uint8_t nexthdr;
129 int err;
130
131 *key_lenp = SW_FLOW_KEY_OFFSET(ipv6.addr);
132
133 err = check_header(skb, nh_ofs + sizeof(*nh));
134 if (unlikely(err))
135 return err;
136
137 nh = ipv6_hdr(skb);
138 nexthdr = nh->nexthdr;
139 payload_ofs = (u8 *)(nh + 1) - skb->data;
140
141 key->ip.nw_proto = NEXTHDR_NONE;
142 key->ip.nw_tos = ipv6_get_dsfield(nh) & ~INET_ECN_MASK;
143 ipv6_addr_copy(&key->ipv6.addr.src, &nh->saddr);
144 ipv6_addr_copy(&key->ipv6.addr.dst, &nh->daddr);
145
146 payload_ofs = ipv6_skip_exthdr(skb, payload_ofs, &nexthdr);
147 if (unlikely(payload_ofs < 0))
148 return -EINVAL;
149
150 nh_len = payload_ofs - nh_ofs;
151 skb_set_transport_header(skb, nh_ofs + nh_len);
152 key->ip.nw_proto = nexthdr;
153 return nh_len;
154 }
155
156 static bool icmp6hdr_ok(struct sk_buff *skb)
157 {
158 return pskb_may_pull(skb, skb_transport_offset(skb) +
159 sizeof(struct icmp6hdr));
160 }
161
162 #define TCP_FLAGS_OFFSET 13
163 #define TCP_FLAG_MASK 0x3f
164
165 void flow_used(struct sw_flow *flow, struct sk_buff *skb)
166 {
167 u8 tcp_flags = 0;
168
169 if (flow->key.eth.type == htons(ETH_P_IP) &&
170 flow->key.ip.nw_proto == IPPROTO_TCP) {
171 u8 *tcp = (u8 *)tcp_hdr(skb);
172 tcp_flags = *(tcp + TCP_FLAGS_OFFSET) & TCP_FLAG_MASK;
173 }
174
175 spin_lock_bh(&flow->lock);
176 flow->used = jiffies;
177 flow->packet_count++;
178 flow->byte_count += skb->len;
179 flow->tcp_flags |= tcp_flags;
180 spin_unlock_bh(&flow->lock);
181 }
182
183 struct sw_flow_actions *flow_actions_alloc(const struct nlattr *actions)
184 {
185 int actions_len = nla_len(actions);
186 struct sw_flow_actions *sfa;
187
188 /* At least DP_MAX_PORTS actions are required to be able to flood a
189 * packet to every port. Factor of 2 allows for setting VLAN tags,
190 * etc. */
191 if (actions_len > 2 * DP_MAX_PORTS * nla_total_size(4))
192 return ERR_PTR(-EINVAL);
193
194 sfa = kmalloc(sizeof(*sfa) + actions_len, GFP_KERNEL);
195 if (!sfa)
196 return ERR_PTR(-ENOMEM);
197
198 sfa->actions_len = actions_len;
199 memcpy(sfa->actions, nla_data(actions), actions_len);
200 return sfa;
201 }
202
203 struct sw_flow *flow_alloc(void)
204 {
205 struct sw_flow *flow;
206
207 flow = kmem_cache_alloc(flow_cache, GFP_KERNEL);
208 if (!flow)
209 return ERR_PTR(-ENOMEM);
210
211 spin_lock_init(&flow->lock);
212 atomic_set(&flow->refcnt, 1);
213 flow->sf_acts = NULL;
214 flow->dead = false;
215
216 return flow;
217 }
218
219 void flow_free_tbl(struct tbl_node *node)
220 {
221 struct sw_flow *flow = flow_cast(node);
222
223 flow->dead = true;
224 flow_put(flow);
225 }
226
227 /* RCU callback used by flow_deferred_free. */
228 static void rcu_free_flow_callback(struct rcu_head *rcu)
229 {
230 struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu);
231
232 flow->dead = true;
233 flow_put(flow);
234 }
235
236 /* Schedules 'flow' to be freed after the next RCU grace period.
237 * The caller must hold rcu_read_lock for this to be sensible. */
238 void flow_deferred_free(struct sw_flow *flow)
239 {
240 call_rcu(&flow->rcu, rcu_free_flow_callback);
241 }
242
243 void flow_hold(struct sw_flow *flow)
244 {
245 atomic_inc(&flow->refcnt);
246 }
247
248 void flow_put(struct sw_flow *flow)
249 {
250 if (unlikely(!flow))
251 return;
252
253 if (atomic_dec_and_test(&flow->refcnt)) {
254 kfree((struct sf_flow_acts __force *)flow->sf_acts);
255 kmem_cache_free(flow_cache, flow);
256 }
257 }
258
259 /* RCU callback used by flow_deferred_free_acts. */
260 static void rcu_free_acts_callback(struct rcu_head *rcu)
261 {
262 struct sw_flow_actions *sf_acts = container_of(rcu,
263 struct sw_flow_actions, rcu);
264 kfree(sf_acts);
265 }
266
267 /* Schedules 'sf_acts' to be freed after the next RCU grace period.
268 * The caller must hold rcu_read_lock for this to be sensible. */
269 void flow_deferred_free_acts(struct sw_flow_actions *sf_acts)
270 {
271 call_rcu(&sf_acts->rcu, rcu_free_acts_callback);
272 }
273
274 static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
275 {
276 struct qtag_prefix {
277 __be16 eth_type; /* ETH_P_8021Q */
278 __be16 tci;
279 };
280 struct qtag_prefix *qp;
281
282 if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) +
283 sizeof(__be16))))
284 return -ENOMEM;
285
286 qp = (struct qtag_prefix *) skb->data;
287 key->eth.tci = qp->tci | htons(VLAN_TAG_PRESENT);
288 __skb_pull(skb, sizeof(struct qtag_prefix));
289
290 return 0;
291 }
292
293 static __be16 parse_ethertype(struct sk_buff *skb)
294 {
295 struct llc_snap_hdr {
296 u8 dsap; /* Always 0xAA */
297 u8 ssap; /* Always 0xAA */
298 u8 ctrl;
299 u8 oui[3];
300 __be16 ethertype;
301 };
302 struct llc_snap_hdr *llc;
303 __be16 proto;
304
305 proto = *(__be16 *) skb->data;
306 __skb_pull(skb, sizeof(__be16));
307
308 if (ntohs(proto) >= 1536)
309 return proto;
310
311 if (skb->len < sizeof(struct llc_snap_hdr))
312 return htons(ETH_P_802_2);
313
314 if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
315 return htons(0);
316
317 llc = (struct llc_snap_hdr *) skb->data;
318 if (llc->dsap != LLC_SAP_SNAP ||
319 llc->ssap != LLC_SAP_SNAP ||
320 (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
321 return htons(ETH_P_802_2);
322
323 __skb_pull(skb, sizeof(struct llc_snap_hdr));
324 return llc->ethertype;
325 }
326
327 static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
328 int *key_lenp, int nh_len)
329 {
330 struct icmp6hdr *icmp = icmp6_hdr(skb);
331 int error = 0;
332 int key_len;
333
334 /* The ICMPv6 type and code fields use the 16-bit transport port
335 * fields, so we need to store them in 16-bit network byte order.
336 */
337 key->ipv6.tp.src = htons(icmp->icmp6_type);
338 key->ipv6.tp.dst = htons(icmp->icmp6_code);
339 key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
340
341 if (icmp->icmp6_code == 0 &&
342 (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
343 icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
344 int icmp_len = skb->len - skb_transport_offset(skb);
345 struct nd_msg *nd;
346 int offset;
347
348 key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
349
350 /* In order to process neighbor discovery options, we need the
351 * entire packet.
352 */
353 if (unlikely(icmp_len < sizeof(*nd)))
354 goto out;
355 if (unlikely(skb_linearize(skb))) {
356 error = -ENOMEM;
357 goto out;
358 }
359
360 nd = (struct nd_msg *)skb_transport_header(skb);
361 ipv6_addr_copy(&key->ipv6.nd.target, &nd->target);
362 key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
363
364 icmp_len -= sizeof(*nd);
365 offset = 0;
366 while (icmp_len >= 8) {
367 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd->opt + offset);
368 int opt_len = nd_opt->nd_opt_len * 8;
369
370 if (unlikely(!opt_len || opt_len > icmp_len))
371 goto invalid;
372
373 /* Store the link layer address if the appropriate
374 * option is provided. It is considered an error if
375 * the same link layer option is specified twice.
376 */
377 if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
378 && opt_len == 8) {
379 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
380 goto invalid;
381 memcpy(key->ipv6.nd.sll,
382 &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
383 } else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
384 && opt_len == 8) {
385 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
386 goto invalid;
387 memcpy(key->ipv6.nd.tll,
388 &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
389 }
390
391 icmp_len -= opt_len;
392 offset += opt_len;
393 }
394 }
395
396 goto out;
397
398 invalid:
399 memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
400 memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
401 memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
402
403 out:
404 *key_lenp = key_len;
405 return error;
406 }
407
408 /**
409 * flow_extract - extracts a flow key from an Ethernet frame.
410 * @skb: sk_buff that contains the frame, with skb->data pointing to the
411 * Ethernet header
412 * @in_port: port number on which @skb was received.
413 * @key: output flow key
414 * @key_lenp: length of output flow key
415 * @is_frag: set to 1 if @skb contains an IPv4 fragment, or to 0 if @skb does
416 * not contain an IPv4 packet or if it is not a fragment.
417 *
418 * The caller must ensure that skb->len >= ETH_HLEN.
419 *
420 * Returns 0 if successful, otherwise a negative errno value.
421 *
422 * Initializes @skb header pointers as follows:
423 *
424 * - skb->mac_header: the Ethernet header.
425 *
426 * - skb->network_header: just past the Ethernet header, or just past the
427 * VLAN header, to the first byte of the Ethernet payload.
428 *
429 * - skb->transport_header: If key->dl_type is ETH_P_IP or ETH_P_IPV6
430 * on output, then just past the IP header, if one is present and
431 * of a correct length, otherwise the same as skb->network_header.
432 * For other key->dl_type values it is left untouched.
433 */
434 int flow_extract(struct sk_buff *skb, u16 in_port, struct sw_flow_key *key,
435 int *key_lenp, bool *is_frag)
436 {
437 int error = 0;
438 int key_len = SW_FLOW_KEY_OFFSET(eth);
439 struct ethhdr *eth;
440
441 memset(key, 0, sizeof(*key));
442 key->eth.tun_id = OVS_CB(skb)->tun_id;
443 key->eth.in_port = in_port;
444 *is_frag = false;
445
446 skb_reset_mac_header(skb);
447
448 /* Link layer. We are guaranteed to have at least the 14 byte Ethernet
449 * header in the linear data area.
450 */
451 eth = eth_hdr(skb);
452 memcpy(key->eth.src, eth->h_source, ETH_ALEN);
453 memcpy(key->eth.dst, eth->h_dest, ETH_ALEN);
454
455 __skb_pull(skb, 2 * ETH_ALEN);
456
457 if (vlan_tx_tag_present(skb))
458 key->eth.tci = htons(vlan_get_tci(skb));
459 else if (eth->h_proto == htons(ETH_P_8021Q))
460 if (unlikely(parse_vlan(skb, key)))
461 return -ENOMEM;
462
463 key->eth.type = parse_ethertype(skb);
464 if (unlikely(key->eth.type == htons(0)))
465 return -ENOMEM;
466
467 skb_reset_network_header(skb);
468 __skb_push(skb, skb->data - skb_mac_header(skb));
469
470 /* Network layer. */
471 if (key->eth.type == htons(ETH_P_IP)) {
472 struct iphdr *nh;
473
474 key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
475
476 error = check_iphdr(skb);
477 if (unlikely(error)) {
478 if (error == -EINVAL) {
479 skb->transport_header = skb->network_header;
480 error = 0;
481 }
482 goto out;
483 }
484
485 nh = ip_hdr(skb);
486 key->ipv4.addr.src = nh->saddr;
487 key->ipv4.addr.dst = nh->daddr;
488 key->ip.nw_tos = nh->tos & ~INET_ECN_MASK;
489 key->ip.nw_proto = nh->protocol;
490
491 /* Transport layer. */
492 if (!(nh->frag_off & htons(IP_MF | IP_OFFSET)) &&
493 !(skb_shinfo(skb)->gso_type & SKB_GSO_UDP)) {
494 if (key->ip.nw_proto == IPPROTO_TCP) {
495 key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
496 if (tcphdr_ok(skb)) {
497 struct tcphdr *tcp = tcp_hdr(skb);
498 key->ipv4.tp.src = tcp->source;
499 key->ipv4.tp.dst = tcp->dest;
500 }
501 } else if (key->ip.nw_proto == IPPROTO_UDP) {
502 key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
503 if (udphdr_ok(skb)) {
504 struct udphdr *udp = udp_hdr(skb);
505 key->ipv4.tp.src = udp->source;
506 key->ipv4.tp.dst = udp->dest;
507 }
508 } else if (key->ip.nw_proto == IPPROTO_ICMP) {
509 key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
510 if (icmphdr_ok(skb)) {
511 struct icmphdr *icmp = icmp_hdr(skb);
512 /* The ICMP type and code fields use the 16-bit
513 * transport port fields, so we need to store them
514 * in 16-bit network byte order. */
515 key->ipv4.tp.src = htons(icmp->type);
516 key->ipv4.tp.dst = htons(icmp->code);
517 }
518 }
519 } else
520 *is_frag = true;
521
522 } else if (key->eth.type == htons(ETH_P_ARP) && arphdr_ok(skb)) {
523 struct arp_eth_header *arp;
524
525 arp = (struct arp_eth_header *)skb_network_header(skb);
526
527 if (arp->ar_hrd == htons(ARPHRD_ETHER)
528 && arp->ar_pro == htons(ETH_P_IP)
529 && arp->ar_hln == ETH_ALEN
530 && arp->ar_pln == 4) {
531
532 /* We only match on the lower 8 bits of the opcode. */
533 if (ntohs(arp->ar_op) <= 0xff)
534 key->ip.nw_proto = ntohs(arp->ar_op);
535
536 if (key->ip.nw_proto == ARPOP_REQUEST
537 || key->ip.nw_proto == ARPOP_REPLY) {
538 memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
539 memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
540 memcpy(key->ipv4.arp.sha, arp->ar_sha, ETH_ALEN);
541 memcpy(key->ipv4.arp.tha, arp->ar_tha, ETH_ALEN);
542 key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
543 }
544 }
545 } else if (key->eth.type == htons(ETH_P_IPV6)) {
546 int nh_len; /* IPv6 Header + Extensions */
547
548 nh_len = parse_ipv6hdr(skb, key, &key_len);
549 if (unlikely(nh_len < 0)) {
550 if (nh_len == -EINVAL)
551 skb->transport_header = skb->network_header;
552 else
553 error = nh_len;
554 goto out;
555 }
556
557 /* Transport layer. */
558 if (key->ip.nw_proto == NEXTHDR_TCP) {
559 key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
560 if (tcphdr_ok(skb)) {
561 struct tcphdr *tcp = tcp_hdr(skb);
562 key->ipv6.tp.src = tcp->source;
563 key->ipv6.tp.dst = tcp->dest;
564 }
565 } else if (key->ip.nw_proto == NEXTHDR_UDP) {
566 key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
567 if (udphdr_ok(skb)) {
568 struct udphdr *udp = udp_hdr(skb);
569 key->ipv6.tp.src = udp->source;
570 key->ipv6.tp.dst = udp->dest;
571 }
572 } else if (key->ip.nw_proto == NEXTHDR_ICMP) {
573 key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
574 if (icmp6hdr_ok(skb)) {
575 error = parse_icmpv6(skb, key, &key_len, nh_len);
576 if (error < 0)
577 goto out;
578 }
579 }
580 }
581
582 out:
583 *key_lenp = key_len;
584 return error;
585 }
586
587 u32 flow_hash(const struct sw_flow_key *key, int key_len)
588 {
589 return jhash2((u32*)key, DIV_ROUND_UP(key_len, sizeof(u32)), hash_seed);
590 }
591
592 int flow_cmp(const struct tbl_node *node, void *key2_, int len)
593 {
594 const struct sw_flow_key *key1 = &flow_cast(node)->key;
595 const struct sw_flow_key *key2 = key2_;
596
597 return !memcmp(key1, key2, len);
598 }
599
600 /* The size of the argument for each %ODP_KEY_ATTR_* Netlink attribute. */
601 static const u32 key_lens[ODP_KEY_ATTR_MAX + 1] = {
602 [ODP_KEY_ATTR_TUN_ID] = 8,
603 [ODP_KEY_ATTR_IN_PORT] = 4,
604 [ODP_KEY_ATTR_ETHERNET] = sizeof(struct odp_key_ethernet),
605 [ODP_KEY_ATTR_8021Q] = sizeof(struct odp_key_8021q),
606 [ODP_KEY_ATTR_ETHERTYPE] = 2,
607 [ODP_KEY_ATTR_IPV4] = sizeof(struct odp_key_ipv4),
608 [ODP_KEY_ATTR_IPV6] = sizeof(struct odp_key_ipv6),
609 [ODP_KEY_ATTR_TCP] = sizeof(struct odp_key_tcp),
610 [ODP_KEY_ATTR_UDP] = sizeof(struct odp_key_udp),
611 [ODP_KEY_ATTR_ICMP] = sizeof(struct odp_key_icmp),
612 [ODP_KEY_ATTR_ICMPV6] = sizeof(struct odp_key_icmpv6),
613 [ODP_KEY_ATTR_ARP] = sizeof(struct odp_key_arp),
614 [ODP_KEY_ATTR_ND] = sizeof(struct odp_key_nd),
615 };
616
617 /**
618 * flow_from_nlattrs - parses Netlink attributes into a flow key.
619 * @swkey: receives the extracted flow key.
620 * @key_lenp: number of bytes used in @swkey.
621 * @attr: Netlink attribute holding nested %ODP_KEY_ATTR_* Netlink attribute
622 * sequence.
623 *
624 * This state machine accepts the following forms, with [] for optional
625 * elements and | for alternatives:
626 *
627 * [tun_id] in_port ethernet [8021q] [ethertype \
628 * [IPv4 [TCP|UDP|ICMP] | IPv6 [TCP|UDP|ICMPv6 [ND]] | ARP]]
629 */
630 int flow_from_nlattrs(struct sw_flow_key *swkey, int *key_lenp,
631 const struct nlattr *attr)
632 {
633 int error = 0;
634 const struct nlattr *nla;
635 u16 prev_type;
636 int rem;
637 int key_len;
638
639 memset(swkey, 0, sizeof(*swkey));
640 swkey->eth.type = htons(ETH_P_802_2);
641 key_len = SW_FLOW_KEY_OFFSET(eth);
642
643 prev_type = ODP_KEY_ATTR_UNSPEC;
644 nla_for_each_nested(nla, attr, rem) {
645 const struct odp_key_ethernet *eth_key;
646 const struct odp_key_8021q *q_key;
647 const struct odp_key_ipv4 *ipv4_key;
648 const struct odp_key_ipv6 *ipv6_key;
649 const struct odp_key_tcp *tcp_key;
650 const struct odp_key_udp *udp_key;
651 const struct odp_key_icmp *icmp_key;
652 const struct odp_key_icmpv6 *icmpv6_key;
653 const struct odp_key_arp *arp_key;
654 const struct odp_key_nd *nd_key;
655
656 int type = nla_type(nla);
657
658 if (type > ODP_KEY_ATTR_MAX || nla_len(nla) != key_lens[type])
659 goto invalid;
660
661 #define TRANSITION(PREV_TYPE, TYPE) (((PREV_TYPE) << 16) | (TYPE))
662 switch (TRANSITION(prev_type, type)) {
663 case TRANSITION(ODP_KEY_ATTR_UNSPEC, ODP_KEY_ATTR_TUN_ID):
664 swkey->eth.tun_id = nla_get_be64(nla);
665 break;
666
667 case TRANSITION(ODP_KEY_ATTR_UNSPEC, ODP_KEY_ATTR_IN_PORT):
668 case TRANSITION(ODP_KEY_ATTR_TUN_ID, ODP_KEY_ATTR_IN_PORT):
669 if (nla_get_u32(nla) >= DP_MAX_PORTS)
670 goto invalid;
671 swkey->eth.in_port = nla_get_u32(nla);
672 break;
673
674 case TRANSITION(ODP_KEY_ATTR_IN_PORT, ODP_KEY_ATTR_ETHERNET):
675 eth_key = nla_data(nla);
676 memcpy(swkey->eth.src, eth_key->eth_src, ETH_ALEN);
677 memcpy(swkey->eth.dst, eth_key->eth_dst, ETH_ALEN);
678 break;
679
680 case TRANSITION(ODP_KEY_ATTR_ETHERNET, ODP_KEY_ATTR_8021Q):
681 q_key = nla_data(nla);
682 /* Only standard 0x8100 VLANs currently supported. */
683 if (q_key->q_tpid != htons(ETH_P_8021Q))
684 goto invalid;
685 if (q_key->q_tci & htons(VLAN_TAG_PRESENT))
686 goto invalid;
687 swkey->eth.tci = q_key->q_tci | htons(VLAN_TAG_PRESENT);
688 break;
689
690 case TRANSITION(ODP_KEY_ATTR_8021Q, ODP_KEY_ATTR_ETHERTYPE):
691 case TRANSITION(ODP_KEY_ATTR_ETHERNET, ODP_KEY_ATTR_ETHERTYPE):
692 swkey->eth.type = nla_get_be16(nla);
693 if (ntohs(swkey->eth.type) < 1536)
694 goto invalid;
695 break;
696
697 case TRANSITION(ODP_KEY_ATTR_ETHERTYPE, ODP_KEY_ATTR_IPV4):
698 key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
699 if (swkey->eth.type != htons(ETH_P_IP))
700 goto invalid;
701 ipv4_key = nla_data(nla);
702 swkey->ip.nw_proto = ipv4_key->ipv4_proto;
703 swkey->ip.nw_tos = ipv4_key->ipv4_tos;
704 swkey->ipv4.addr.src = ipv4_key->ipv4_src;
705 swkey->ipv4.addr.dst = ipv4_key->ipv4_dst;
706 if (swkey->ip.nw_tos & INET_ECN_MASK)
707 goto invalid;
708 break;
709
710 case TRANSITION(ODP_KEY_ATTR_ETHERTYPE, ODP_KEY_ATTR_IPV6):
711 key_len = SW_FLOW_KEY_OFFSET(ipv6.addr);
712 if (swkey->eth.type != htons(ETH_P_IPV6))
713 goto invalid;
714 ipv6_key = nla_data(nla);
715 swkey->ip.nw_proto = ipv6_key->ipv6_proto;
716 swkey->ip.nw_tos = ipv6_key->ipv6_tos;
717 memcpy(&swkey->ipv6.addr.src, ipv6_key->ipv6_src,
718 sizeof(swkey->ipv6.addr.src));
719 memcpy(&swkey->ipv6.addr.dst, ipv6_key->ipv6_dst,
720 sizeof(swkey->ipv6.addr.dst));
721 if (swkey->ip.nw_tos & INET_ECN_MASK)
722 goto invalid;
723 break;
724
725 case TRANSITION(ODP_KEY_ATTR_IPV4, ODP_KEY_ATTR_TCP):
726 key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
727 if (swkey->ip.nw_proto != IPPROTO_TCP)
728 goto invalid;
729 tcp_key = nla_data(nla);
730 swkey->ipv4.tp.src = tcp_key->tcp_src;
731 swkey->ipv4.tp.dst = tcp_key->tcp_dst;
732 break;
733
734 case TRANSITION(ODP_KEY_ATTR_IPV6, ODP_KEY_ATTR_TCP):
735 key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
736 if (swkey->ip.nw_proto != IPPROTO_TCP)
737 goto invalid;
738 tcp_key = nla_data(nla);
739 swkey->ipv6.tp.src = tcp_key->tcp_src;
740 swkey->ipv6.tp.dst = tcp_key->tcp_dst;
741 break;
742
743 case TRANSITION(ODP_KEY_ATTR_IPV4, ODP_KEY_ATTR_UDP):
744 key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
745 if (swkey->ip.nw_proto != IPPROTO_UDP)
746 goto invalid;
747 udp_key = nla_data(nla);
748 swkey->ipv4.tp.src = udp_key->udp_src;
749 swkey->ipv4.tp.dst = udp_key->udp_dst;
750 break;
751
752 case TRANSITION(ODP_KEY_ATTR_IPV6, ODP_KEY_ATTR_UDP):
753 key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
754 if (swkey->ip.nw_proto != IPPROTO_UDP)
755 goto invalid;
756 udp_key = nla_data(nla);
757 swkey->ipv6.tp.src = udp_key->udp_src;
758 swkey->ipv6.tp.dst = udp_key->udp_dst;
759 break;
760
761 case TRANSITION(ODP_KEY_ATTR_IPV4, ODP_KEY_ATTR_ICMP):
762 key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
763 if (swkey->ip.nw_proto != IPPROTO_ICMP)
764 goto invalid;
765 icmp_key = nla_data(nla);
766 swkey->ipv4.tp.src = htons(icmp_key->icmp_type);
767 swkey->ipv4.tp.dst = htons(icmp_key->icmp_code);
768 break;
769
770 case TRANSITION(ODP_KEY_ATTR_IPV6, ODP_KEY_ATTR_ICMPV6):
771 key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
772 if (swkey->ip.nw_proto != IPPROTO_ICMPV6)
773 goto invalid;
774 icmpv6_key = nla_data(nla);
775 swkey->ipv6.tp.src = htons(icmpv6_key->icmpv6_type);
776 swkey->ipv6.tp.dst = htons(icmpv6_key->icmpv6_code);
777 break;
778
779 case TRANSITION(ODP_KEY_ATTR_ETHERTYPE, ODP_KEY_ATTR_ARP):
780 key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
781 if (swkey->eth.type != htons(ETH_P_ARP))
782 goto invalid;
783 arp_key = nla_data(nla);
784 swkey->ipv4.addr.src = arp_key->arp_sip;
785 swkey->ipv4.addr.dst = arp_key->arp_tip;
786 if (arp_key->arp_op & htons(0xff00))
787 goto invalid;
788 swkey->ip.nw_proto = ntohs(arp_key->arp_op);
789 memcpy(swkey->ipv4.arp.sha, arp_key->arp_sha, ETH_ALEN);
790 memcpy(swkey->ipv4.arp.tha, arp_key->arp_tha, ETH_ALEN);
791 break;
792
793 case TRANSITION(ODP_KEY_ATTR_ICMPV6, ODP_KEY_ATTR_ND):
794 key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
795 if (swkey->ipv6.tp.src != htons(NDISC_NEIGHBOUR_SOLICITATION)
796 && swkey->ipv6.tp.src != htons(NDISC_NEIGHBOUR_ADVERTISEMENT))
797 goto invalid;
798 nd_key = nla_data(nla);
799 memcpy(&swkey->ipv6.nd.target, nd_key->nd_target,
800 sizeof(swkey->ipv6.nd.target));
801 memcpy(swkey->ipv6.nd.sll, nd_key->nd_sll, ETH_ALEN);
802 memcpy(swkey->ipv6.nd.tll, nd_key->nd_tll, ETH_ALEN);
803 break;
804
805 default:
806 goto invalid;
807 }
808
809 prev_type = type;
810 }
811 if (rem)
812 goto invalid;
813
814 switch (prev_type) {
815 case ODP_KEY_ATTR_UNSPEC:
816 goto invalid;
817
818 case ODP_KEY_ATTR_TUN_ID:
819 case ODP_KEY_ATTR_IN_PORT:
820 goto invalid;
821
822 case ODP_KEY_ATTR_ETHERNET:
823 case ODP_KEY_ATTR_8021Q:
824 goto ok;
825
826 case ODP_KEY_ATTR_ETHERTYPE:
827 if (swkey->eth.type == htons(ETH_P_IP) ||
828 swkey->eth.type == htons(ETH_P_ARP))
829 goto invalid;
830 goto ok;
831
832 case ODP_KEY_ATTR_IPV4:
833 if (swkey->ip.nw_proto == IPPROTO_TCP ||
834 swkey->ip.nw_proto == IPPROTO_UDP ||
835 swkey->ip.nw_proto == IPPROTO_ICMP)
836 goto invalid;
837 goto ok;
838
839 case ODP_KEY_ATTR_IPV6:
840 if (swkey->ip.nw_proto == IPPROTO_TCP ||
841 swkey->ip.nw_proto == IPPROTO_UDP ||
842 swkey->ip.nw_proto == IPPROTO_ICMPV6)
843 goto invalid;
844 goto ok;
845
846 case ODP_KEY_ATTR_ICMPV6:
847 if (swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_SOLICITATION) ||
848 swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_ADVERTISEMENT))
849 goto invalid;
850 goto ok;
851
852 case ODP_KEY_ATTR_TCP:
853 case ODP_KEY_ATTR_UDP:
854 case ODP_KEY_ATTR_ICMP:
855 case ODP_KEY_ATTR_ARP:
856 case ODP_KEY_ATTR_ND:
857 goto ok;
858
859 default:
860 WARN_ON_ONCE(1);
861 }
862
863 invalid:
864 error = -EINVAL;
865
866 ok:
867 WARN_ON_ONCE(!key_len && !error);
868 *key_lenp = key_len;
869 return error;
870 }
871
872 /**
873 * flow_metadata_from_nlattrs - parses Netlink attributes into a flow key.
874 * @in_port: receives the extracted input port.
875 * @tun_id: receives the extracted tunnel ID.
876 * @key: Netlink attribute holding nested %ODP_KEY_ATTR_* Netlink attribute
877 * sequence.
878 *
879 * This parses a series of Netlink attributes that form a flow key, which must
880 * take the same form accepted by flow_from_nlattrs(), but only enough of it to
881 * get the metadata, that is, the parts of the flow key that cannot be
882 * extracted from the packet itself.
883 */
884 int flow_metadata_from_nlattrs(u16 *in_port, __be64 *tun_id,
885 const struct nlattr *attr)
886 {
887 const struct nlattr *nla;
888 u16 prev_type;
889 int rem;
890
891 *tun_id = 0;
892
893 prev_type = ODP_KEY_ATTR_UNSPEC;
894 nla_for_each_nested(nla, attr, rem) {
895 int type = nla_type(nla);
896
897 if (type > ODP_KEY_ATTR_MAX || nla_len(nla) != key_lens[type])
898 return -EINVAL;
899
900 switch (TRANSITION(prev_type, type)) {
901 case TRANSITION(ODP_KEY_ATTR_UNSPEC, ODP_KEY_ATTR_TUN_ID):
902 *tun_id = nla_get_be64(nla);
903 break;
904
905 case TRANSITION(ODP_KEY_ATTR_UNSPEC, ODP_KEY_ATTR_IN_PORT):
906 case TRANSITION(ODP_KEY_ATTR_TUN_ID, ODP_KEY_ATTR_IN_PORT):
907 if (nla_get_u32(nla) >= DP_MAX_PORTS)
908 return -EINVAL;
909 *in_port = nla_get_u32(nla);
910 break;
911
912 default:
913 goto done;
914 }
915
916 prev_type = type;
917 }
918 if (rem)
919 return -EINVAL;
920
921 done:
922 if (prev_type == ODP_KEY_ATTR_UNSPEC ||
923 prev_type == ODP_KEY_ATTR_TUN_ID)
924 return -EINVAL;
925 return 0;
926 }
927
928 int flow_to_nlattrs(const struct sw_flow_key *swkey, struct sk_buff *skb)
929 {
930 struct odp_key_ethernet *eth_key;
931 struct nlattr *nla;
932
933 /* This is an imperfect sanity-check that FLOW_BUFSIZE doesn't need
934 * to be updated, but will at least raise awareness when new ODP key
935 * types are added. */
936 BUILD_BUG_ON(__ODP_KEY_ATTR_MAX != 14);
937
938 if (swkey->eth.tun_id != cpu_to_be64(0))
939 NLA_PUT_BE64(skb, ODP_KEY_ATTR_TUN_ID, swkey->eth.tun_id);
940
941 NLA_PUT_U32(skb, ODP_KEY_ATTR_IN_PORT, swkey->eth.in_port);
942
943 nla = nla_reserve(skb, ODP_KEY_ATTR_ETHERNET, sizeof(*eth_key));
944 if (!nla)
945 goto nla_put_failure;
946 eth_key = nla_data(nla);
947 memcpy(eth_key->eth_src, swkey->eth.src, ETH_ALEN);
948 memcpy(eth_key->eth_dst, swkey->eth.dst, ETH_ALEN);
949
950 if (swkey->eth.tci != htons(0)) {
951 struct odp_key_8021q q_key;
952
953 q_key.q_tpid = htons(ETH_P_8021Q);
954 q_key.q_tci = swkey->eth.tci & ~htons(VLAN_TAG_PRESENT);
955 NLA_PUT(skb, ODP_KEY_ATTR_8021Q, sizeof(q_key), &q_key);
956 }
957
958 if (swkey->eth.type == htons(ETH_P_802_2))
959 return 0;
960
961 NLA_PUT_BE16(skb, ODP_KEY_ATTR_ETHERTYPE, swkey->eth.type);
962
963 if (swkey->eth.type == htons(ETH_P_IP)) {
964 struct odp_key_ipv4 *ipv4_key;
965
966 nla = nla_reserve(skb, ODP_KEY_ATTR_IPV4, sizeof(*ipv4_key));
967 if (!nla)
968 goto nla_put_failure;
969 ipv4_key = nla_data(nla);
970 memset(ipv4_key, 0, sizeof(struct odp_key_ipv4));
971 ipv4_key->ipv4_src = swkey->ipv4.addr.src;
972 ipv4_key->ipv4_dst = swkey->ipv4.addr.dst;
973 ipv4_key->ipv4_proto = swkey->ip.nw_proto;
974 ipv4_key->ipv4_tos = swkey->ip.nw_tos;
975 } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
976 struct odp_key_ipv6 *ipv6_key;
977
978 nla = nla_reserve(skb, ODP_KEY_ATTR_IPV6, sizeof(*ipv6_key));
979 if (!nla)
980 goto nla_put_failure;
981 ipv6_key = nla_data(nla);
982 memset(ipv6_key, 0, sizeof(struct odp_key_ipv6));
983 memcpy(ipv6_key->ipv6_src, &swkey->ipv6.addr.src,
984 sizeof(ipv6_key->ipv6_src));
985 memcpy(ipv6_key->ipv6_dst, &swkey->ipv6.addr.dst,
986 sizeof(ipv6_key->ipv6_dst));
987 ipv6_key->ipv6_proto = swkey->ip.nw_proto;
988 ipv6_key->ipv6_tos = swkey->ip.nw_tos;
989 } else if (swkey->eth.type == htons(ETH_P_ARP)) {
990 struct odp_key_arp *arp_key;
991
992 nla = nla_reserve(skb, ODP_KEY_ATTR_ARP, sizeof(*arp_key));
993 if (!nla)
994 goto nla_put_failure;
995 arp_key = nla_data(nla);
996 memset(arp_key, 0, sizeof(struct odp_key_arp));
997 arp_key->arp_sip = swkey->ipv4.addr.src;
998 arp_key->arp_tip = swkey->ipv4.addr.dst;
999 arp_key->arp_op = htons(swkey->ip.nw_proto);
1000 memcpy(arp_key->arp_sha, swkey->ipv4.arp.sha, ETH_ALEN);
1001 memcpy(arp_key->arp_tha, swkey->ipv4.arp.tha, ETH_ALEN);
1002 }
1003
1004 if (swkey->eth.type == htons(ETH_P_IP) ||
1005 swkey->eth.type == htons(ETH_P_IPV6)) {
1006
1007 if (swkey->ip.nw_proto == IPPROTO_TCP) {
1008 struct odp_key_tcp *tcp_key;
1009
1010 nla = nla_reserve(skb, ODP_KEY_ATTR_TCP, sizeof(*tcp_key));
1011 if (!nla)
1012 goto nla_put_failure;
1013 tcp_key = nla_data(nla);
1014 if (swkey->eth.type == htons(ETH_P_IP)) {
1015 tcp_key->tcp_src = swkey->ipv4.tp.src;
1016 tcp_key->tcp_dst = swkey->ipv4.tp.dst;
1017 } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1018 tcp_key->tcp_src = swkey->ipv6.tp.src;
1019 tcp_key->tcp_dst = swkey->ipv6.tp.dst;
1020 }
1021 } else if (swkey->ip.nw_proto == IPPROTO_UDP) {
1022 struct odp_key_udp *udp_key;
1023
1024 nla = nla_reserve(skb, ODP_KEY_ATTR_UDP, sizeof(*udp_key));
1025 if (!nla)
1026 goto nla_put_failure;
1027 udp_key = nla_data(nla);
1028 if (swkey->eth.type == htons(ETH_P_IP)) {
1029 udp_key->udp_src = swkey->ipv4.tp.src;
1030 udp_key->udp_dst = swkey->ipv4.tp.dst;
1031 } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1032 udp_key->udp_src = swkey->ipv6.tp.src;
1033 udp_key->udp_dst = swkey->ipv6.tp.dst;
1034 }
1035 } else if (swkey->eth.type == htons(ETH_P_IP) &&
1036 swkey->ip.nw_proto == IPPROTO_ICMP) {
1037 struct odp_key_icmp *icmp_key;
1038
1039 nla = nla_reserve(skb, ODP_KEY_ATTR_ICMP, sizeof(*icmp_key));
1040 if (!nla)
1041 goto nla_put_failure;
1042 icmp_key = nla_data(nla);
1043 icmp_key->icmp_type = ntohs(swkey->ipv4.tp.src);
1044 icmp_key->icmp_code = ntohs(swkey->ipv4.tp.dst);
1045 } else if (swkey->eth.type == htons(ETH_P_IPV6) &&
1046 swkey->ip.nw_proto == IPPROTO_ICMPV6) {
1047 struct odp_key_icmpv6 *icmpv6_key;
1048
1049 nla = nla_reserve(skb, ODP_KEY_ATTR_ICMPV6,
1050 sizeof(*icmpv6_key));
1051 if (!nla)
1052 goto nla_put_failure;
1053 icmpv6_key = nla_data(nla);
1054 icmpv6_key->icmpv6_type = ntohs(swkey->ipv6.tp.src);
1055 icmpv6_key->icmpv6_code = ntohs(swkey->ipv6.tp.dst);
1056
1057 if (icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_SOLICITATION ||
1058 icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_ADVERTISEMENT) {
1059 struct odp_key_nd *nd_key;
1060
1061 nla = nla_reserve(skb, ODP_KEY_ATTR_ND, sizeof(*nd_key));
1062 if (!nla)
1063 goto nla_put_failure;
1064 nd_key = nla_data(nla);
1065 memcpy(nd_key->nd_target, &swkey->ipv6.nd.target,
1066 sizeof(nd_key->nd_target));
1067 memcpy(nd_key->nd_sll, swkey->ipv6.nd.sll, ETH_ALEN);
1068 memcpy(nd_key->nd_tll, swkey->ipv6.nd.tll, ETH_ALEN);
1069 }
1070 }
1071 }
1072
1073 return 0;
1074
1075 nla_put_failure:
1076 return -EMSGSIZE;
1077 }
1078
1079 /* Initializes the flow module.
1080 * Returns zero if successful or a negative error code. */
1081 int flow_init(void)
1082 {
1083 flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow), 0,
1084 0, NULL);
1085 if (flow_cache == NULL)
1086 return -ENOMEM;
1087
1088 get_random_bytes(&hash_seed, sizeof(hash_seed));
1089
1090 return 0;
1091 }
1092
1093 /* Uninitializes the flow module. */
1094 void flow_exit(void)
1095 {
1096 kmem_cache_destroy(flow_cache);
1097 }
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