xref: /linux/drivers/infiniband/core/addr.c (revision feb7c1e38bccfd18cc06677cb648ed2340788fe8)
1 /*
2  * Copyright (c) 2005 Voltaire Inc.  All rights reserved.
3  * Copyright (c) 2002-2005, Network Appliance, Inc. All rights reserved.
4  * Copyright (c) 1999-2005, Mellanox Technologies, Inc. All rights reserved.
5  * Copyright (c) 2005 Intel Corporation.  All rights reserved.
6  *
7  * This software is available to you under a choice of one of two
8  * licenses.  You may choose to be licensed under the terms of the GNU
9  * General Public License (GPL) Version 2, available from the file
10  * COPYING in the main directory of this source tree, or the
11  * OpenIB.org BSD license below:
12  *
13  *     Redistribution and use in source and binary forms, with or
14  *     without modification, are permitted provided that the following
15  *     conditions are met:
16  *
17  *      - Redistributions of source code must retain the above
18  *        copyright notice, this list of conditions and the following
19  *        disclaimer.
20  *
21  *      - Redistributions in binary form must reproduce the above
22  *        copyright notice, this list of conditions and the following
23  *        disclaimer in the documentation and/or other materials
24  *        provided with the distribution.
25  *
26  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
27  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
28  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
29  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
30  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
31  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
32  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
33  * SOFTWARE.
34  */
35 
36 #include <linux/mutex.h>
37 #include <linux/inetdevice.h>
38 #include <linux/slab.h>
39 #include <linux/workqueue.h>
40 #include <linux/module.h>
41 #include <net/arp.h>
42 #include <net/neighbour.h>
43 #include <net/route.h>
44 #include <net/netevent.h>
45 #include <net/addrconf.h>
46 #include <net/ip6_route.h>
47 #include <rdma/ib_addr.h>
48 #include <rdma/ib.h>
49 
50 MODULE_AUTHOR("Sean Hefty");
51 MODULE_DESCRIPTION("IB Address Translation");
52 MODULE_LICENSE("Dual BSD/GPL");
53 
54 struct addr_req {
55 	struct list_head list;
56 	struct sockaddr_storage src_addr;
57 	struct sockaddr_storage dst_addr;
58 	struct rdma_dev_addr *addr;
59 	struct rdma_addr_client *client;
60 	void *context;
61 	void (*callback)(int status, struct sockaddr *src_addr,
62 			 struct rdma_dev_addr *addr, void *context);
63 	unsigned long timeout;
64 	int status;
65 };
66 
67 static void process_req(struct work_struct *work);
68 
69 static DEFINE_MUTEX(lock);
70 static LIST_HEAD(req_list);
71 static DECLARE_DELAYED_WORK(work, process_req);
72 static struct workqueue_struct *addr_wq;
73 
74 int rdma_addr_size(struct sockaddr *addr)
75 {
76 	switch (addr->sa_family) {
77 	case AF_INET:
78 		return sizeof(struct sockaddr_in);
79 	case AF_INET6:
80 		return sizeof(struct sockaddr_in6);
81 	case AF_IB:
82 		return sizeof(struct sockaddr_ib);
83 	default:
84 		return 0;
85 	}
86 }
87 EXPORT_SYMBOL(rdma_addr_size);
88 
89 static struct rdma_addr_client self;
90 
91 void rdma_addr_register_client(struct rdma_addr_client *client)
92 {
93 	atomic_set(&client->refcount, 1);
94 	init_completion(&client->comp);
95 }
96 EXPORT_SYMBOL(rdma_addr_register_client);
97 
98 static inline void put_client(struct rdma_addr_client *client)
99 {
100 	if (atomic_dec_and_test(&client->refcount))
101 		complete(&client->comp);
102 }
103 
104 void rdma_addr_unregister_client(struct rdma_addr_client *client)
105 {
106 	put_client(client);
107 	wait_for_completion(&client->comp);
108 }
109 EXPORT_SYMBOL(rdma_addr_unregister_client);
110 
111 int rdma_copy_addr(struct rdma_dev_addr *dev_addr, struct net_device *dev,
112 		     const unsigned char *dst_dev_addr)
113 {
114 	dev_addr->dev_type = dev->type;
115 	memcpy(dev_addr->src_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
116 	memcpy(dev_addr->broadcast, dev->broadcast, MAX_ADDR_LEN);
117 	if (dst_dev_addr)
118 		memcpy(dev_addr->dst_dev_addr, dst_dev_addr, MAX_ADDR_LEN);
119 	dev_addr->bound_dev_if = dev->ifindex;
120 	return 0;
121 }
122 EXPORT_SYMBOL(rdma_copy_addr);
123 
124 int rdma_translate_ip(const struct sockaddr *addr,
125 		      struct rdma_dev_addr *dev_addr,
126 		      u16 *vlan_id)
127 {
128 	struct net_device *dev;
129 	int ret = -EADDRNOTAVAIL;
130 
131 	if (dev_addr->bound_dev_if) {
132 		dev = dev_get_by_index(dev_addr->net, dev_addr->bound_dev_if);
133 		if (!dev)
134 			return -ENODEV;
135 		ret = rdma_copy_addr(dev_addr, dev, NULL);
136 		dev_put(dev);
137 		return ret;
138 	}
139 
140 	switch (addr->sa_family) {
141 	case AF_INET:
142 		dev = ip_dev_find(dev_addr->net,
143 			((const struct sockaddr_in *)addr)->sin_addr.s_addr);
144 
145 		if (!dev)
146 			return ret;
147 
148 		ret = rdma_copy_addr(dev_addr, dev, NULL);
149 		if (vlan_id)
150 			*vlan_id = rdma_vlan_dev_vlan_id(dev);
151 		dev_put(dev);
152 		break;
153 #if IS_ENABLED(CONFIG_IPV6)
154 	case AF_INET6:
155 		rcu_read_lock();
156 		for_each_netdev_rcu(dev_addr->net, dev) {
157 			if (ipv6_chk_addr(dev_addr->net,
158 					  &((const struct sockaddr_in6 *)addr)->sin6_addr,
159 					  dev, 1)) {
160 				ret = rdma_copy_addr(dev_addr, dev, NULL);
161 				if (vlan_id)
162 					*vlan_id = rdma_vlan_dev_vlan_id(dev);
163 				break;
164 			}
165 		}
166 		rcu_read_unlock();
167 		break;
168 #endif
169 	}
170 	return ret;
171 }
172 EXPORT_SYMBOL(rdma_translate_ip);
173 
174 static void set_timeout(unsigned long time)
175 {
176 	unsigned long delay;
177 
178 	delay = time - jiffies;
179 	if ((long)delay < 0)
180 		delay = 0;
181 
182 	mod_delayed_work(addr_wq, &work, delay);
183 }
184 
185 static void queue_req(struct addr_req *req)
186 {
187 	struct addr_req *temp_req;
188 
189 	mutex_lock(&lock);
190 	list_for_each_entry_reverse(temp_req, &req_list, list) {
191 		if (time_after_eq(req->timeout, temp_req->timeout))
192 			break;
193 	}
194 
195 	list_add(&req->list, &temp_req->list);
196 
197 	if (req_list.next == &req->list)
198 		set_timeout(req->timeout);
199 	mutex_unlock(&lock);
200 }
201 
202 static int dst_fetch_ha(struct dst_entry *dst, struct rdma_dev_addr *dev_addr,
203 			const void *daddr)
204 {
205 	struct neighbour *n;
206 	int ret;
207 
208 	n = dst_neigh_lookup(dst, daddr);
209 
210 	rcu_read_lock();
211 	if (!n || !(n->nud_state & NUD_VALID)) {
212 		if (n)
213 			neigh_event_send(n, NULL);
214 		ret = -ENODATA;
215 	} else {
216 		ret = rdma_copy_addr(dev_addr, dst->dev, n->ha);
217 	}
218 	rcu_read_unlock();
219 
220 	if (n)
221 		neigh_release(n);
222 
223 	return ret;
224 }
225 
226 static int addr4_resolve(struct sockaddr_in *src_in,
227 			 const struct sockaddr_in *dst_in,
228 			 struct rdma_dev_addr *addr,
229 			 struct rtable **prt)
230 {
231 	__be32 src_ip = src_in->sin_addr.s_addr;
232 	__be32 dst_ip = dst_in->sin_addr.s_addr;
233 	struct rtable *rt;
234 	struct flowi4 fl4;
235 	int ret;
236 
237 	memset(&fl4, 0, sizeof(fl4));
238 	fl4.daddr = dst_ip;
239 	fl4.saddr = src_ip;
240 	fl4.flowi4_oif = addr->bound_dev_if;
241 	rt = ip_route_output_key(addr->net, &fl4);
242 	if (IS_ERR(rt)) {
243 		ret = PTR_ERR(rt);
244 		goto out;
245 	}
246 	src_in->sin_family = AF_INET;
247 	src_in->sin_addr.s_addr = fl4.saddr;
248 
249 	/* If there's a gateway, we're definitely in RoCE v2 (as RoCE v1 isn't
250 	 * routable) and we could set the network type accordingly.
251 	 */
252 	if (rt->rt_uses_gateway)
253 		addr->network = RDMA_NETWORK_IPV4;
254 
255 	*prt = rt;
256 	return 0;
257 out:
258 	return ret;
259 }
260 
261 #if IS_ENABLED(CONFIG_IPV6)
262 static int addr6_resolve(struct sockaddr_in6 *src_in,
263 			 const struct sockaddr_in6 *dst_in,
264 			 struct rdma_dev_addr *addr,
265 			 struct dst_entry **pdst)
266 {
267 	struct flowi6 fl6;
268 	struct dst_entry *dst;
269 	struct rt6_info *rt;
270 	int ret;
271 
272 	memset(&fl6, 0, sizeof fl6);
273 	fl6.daddr = dst_in->sin6_addr;
274 	fl6.saddr = src_in->sin6_addr;
275 	fl6.flowi6_oif = addr->bound_dev_if;
276 
277 	dst = ip6_route_output(addr->net, NULL, &fl6);
278 	if ((ret = dst->error))
279 		goto put;
280 
281 	rt = (struct rt6_info *)dst;
282 	if (ipv6_addr_any(&fl6.saddr)) {
283 		ret = ipv6_dev_get_saddr(addr->net, ip6_dst_idev(dst)->dev,
284 					 &fl6.daddr, 0, &fl6.saddr);
285 		if (ret)
286 			goto put;
287 
288 		src_in->sin6_family = AF_INET6;
289 		src_in->sin6_addr = fl6.saddr;
290 	}
291 
292 	/* If there's a gateway, we're definitely in RoCE v2 (as RoCE v1 isn't
293 	 * routable) and we could set the network type accordingly.
294 	 */
295 	if (rt->rt6i_flags & RTF_GATEWAY)
296 		addr->network = RDMA_NETWORK_IPV6;
297 
298 	*pdst = dst;
299 	return 0;
300 put:
301 	dst_release(dst);
302 	return ret;
303 }
304 #else
305 static int addr6_resolve(struct sockaddr_in6 *src_in,
306 			 const struct sockaddr_in6 *dst_in,
307 			 struct rdma_dev_addr *addr,
308 			 struct dst_entry **pdst)
309 {
310 	return -EADDRNOTAVAIL;
311 }
312 #endif
313 
314 static int addr_resolve_neigh(struct dst_entry *dst,
315 			      const struct sockaddr *dst_in,
316 			      struct rdma_dev_addr *addr)
317 {
318 	if (dst->dev->flags & IFF_LOOPBACK) {
319 		int ret;
320 
321 		ret = rdma_translate_ip(dst_in, addr, NULL);
322 		if (!ret)
323 			memcpy(addr->dst_dev_addr, addr->src_dev_addr,
324 			       MAX_ADDR_LEN);
325 
326 		return ret;
327 	}
328 
329 	/* If the device doesn't do ARP internally */
330 	if (!(dst->dev->flags & IFF_NOARP)) {
331 		const struct sockaddr_in *dst_in4 =
332 			(const struct sockaddr_in *)dst_in;
333 		const struct sockaddr_in6 *dst_in6 =
334 			(const struct sockaddr_in6 *)dst_in;
335 
336 		return dst_fetch_ha(dst, addr,
337 				    dst_in->sa_family == AF_INET ?
338 				    (const void *)&dst_in4->sin_addr.s_addr :
339 				    (const void *)&dst_in6->sin6_addr);
340 	}
341 
342 	return rdma_copy_addr(addr, dst->dev, NULL);
343 }
344 
345 static int addr_resolve(struct sockaddr *src_in,
346 			const struct sockaddr *dst_in,
347 			struct rdma_dev_addr *addr,
348 			bool resolve_neigh)
349 {
350 	struct net_device *ndev;
351 	struct dst_entry *dst;
352 	int ret;
353 
354 	if (src_in->sa_family == AF_INET) {
355 		struct rtable *rt = NULL;
356 		const struct sockaddr_in *dst_in4 =
357 			(const struct sockaddr_in *)dst_in;
358 
359 		ret = addr4_resolve((struct sockaddr_in *)src_in,
360 				    dst_in4, addr, &rt);
361 		if (ret)
362 			return ret;
363 
364 		if (resolve_neigh)
365 			ret = addr_resolve_neigh(&rt->dst, dst_in, addr);
366 
367 		ndev = rt->dst.dev;
368 		dev_hold(ndev);
369 
370 		ip_rt_put(rt);
371 	} else {
372 		const struct sockaddr_in6 *dst_in6 =
373 			(const struct sockaddr_in6 *)dst_in;
374 
375 		ret = addr6_resolve((struct sockaddr_in6 *)src_in,
376 				    dst_in6, addr,
377 				    &dst);
378 		if (ret)
379 			return ret;
380 
381 		if (resolve_neigh)
382 			ret = addr_resolve_neigh(dst, dst_in, addr);
383 
384 		ndev = dst->dev;
385 		dev_hold(ndev);
386 
387 		dst_release(dst);
388 	}
389 
390 	addr->bound_dev_if = ndev->ifindex;
391 	addr->net = dev_net(ndev);
392 	dev_put(ndev);
393 
394 	return ret;
395 }
396 
397 static void process_req(struct work_struct *work)
398 {
399 	struct addr_req *req, *temp_req;
400 	struct sockaddr *src_in, *dst_in;
401 	struct list_head done_list;
402 
403 	INIT_LIST_HEAD(&done_list);
404 
405 	mutex_lock(&lock);
406 	list_for_each_entry_safe(req, temp_req, &req_list, list) {
407 		if (req->status == -ENODATA) {
408 			src_in = (struct sockaddr *) &req->src_addr;
409 			dst_in = (struct sockaddr *) &req->dst_addr;
410 			req->status = addr_resolve(src_in, dst_in, req->addr,
411 						   true);
412 			if (req->status && time_after_eq(jiffies, req->timeout))
413 				req->status = -ETIMEDOUT;
414 			else if (req->status == -ENODATA)
415 				continue;
416 		}
417 		list_move_tail(&req->list, &done_list);
418 	}
419 
420 	if (!list_empty(&req_list)) {
421 		req = list_entry(req_list.next, struct addr_req, list);
422 		set_timeout(req->timeout);
423 	}
424 	mutex_unlock(&lock);
425 
426 	list_for_each_entry_safe(req, temp_req, &done_list, list) {
427 		list_del(&req->list);
428 		req->callback(req->status, (struct sockaddr *) &req->src_addr,
429 			req->addr, req->context);
430 		put_client(req->client);
431 		kfree(req);
432 	}
433 }
434 
435 int rdma_resolve_ip(struct rdma_addr_client *client,
436 		    struct sockaddr *src_addr, struct sockaddr *dst_addr,
437 		    struct rdma_dev_addr *addr, int timeout_ms,
438 		    void (*callback)(int status, struct sockaddr *src_addr,
439 				     struct rdma_dev_addr *addr, void *context),
440 		    void *context)
441 {
442 	struct sockaddr *src_in, *dst_in;
443 	struct addr_req *req;
444 	int ret = 0;
445 
446 	req = kzalloc(sizeof *req, GFP_KERNEL);
447 	if (!req)
448 		return -ENOMEM;
449 
450 	src_in = (struct sockaddr *) &req->src_addr;
451 	dst_in = (struct sockaddr *) &req->dst_addr;
452 
453 	if (src_addr) {
454 		if (src_addr->sa_family != dst_addr->sa_family) {
455 			ret = -EINVAL;
456 			goto err;
457 		}
458 
459 		memcpy(src_in, src_addr, rdma_addr_size(src_addr));
460 	} else {
461 		src_in->sa_family = dst_addr->sa_family;
462 	}
463 
464 	memcpy(dst_in, dst_addr, rdma_addr_size(dst_addr));
465 	req->addr = addr;
466 	req->callback = callback;
467 	req->context = context;
468 	req->client = client;
469 	atomic_inc(&client->refcount);
470 
471 	req->status = addr_resolve(src_in, dst_in, addr, true);
472 	switch (req->status) {
473 	case 0:
474 		req->timeout = jiffies;
475 		queue_req(req);
476 		break;
477 	case -ENODATA:
478 		req->timeout = msecs_to_jiffies(timeout_ms) + jiffies;
479 		queue_req(req);
480 		break;
481 	default:
482 		ret = req->status;
483 		atomic_dec(&client->refcount);
484 		goto err;
485 	}
486 	return ret;
487 err:
488 	kfree(req);
489 	return ret;
490 }
491 EXPORT_SYMBOL(rdma_resolve_ip);
492 
493 int rdma_resolve_ip_route(struct sockaddr *src_addr,
494 			  const struct sockaddr *dst_addr,
495 			  struct rdma_dev_addr *addr)
496 {
497 	struct sockaddr_storage ssrc_addr = {};
498 	struct sockaddr *src_in = (struct sockaddr *)&ssrc_addr;
499 
500 	if (src_addr->sa_family != dst_addr->sa_family)
501 		return -EINVAL;
502 
503 	if (src_addr)
504 		memcpy(src_in, src_addr, rdma_addr_size(src_addr));
505 	else
506 		src_in->sa_family = dst_addr->sa_family;
507 
508 	return addr_resolve(src_in, dst_addr, addr, false);
509 }
510 EXPORT_SYMBOL(rdma_resolve_ip_route);
511 
512 void rdma_addr_cancel(struct rdma_dev_addr *addr)
513 {
514 	struct addr_req *req, *temp_req;
515 
516 	mutex_lock(&lock);
517 	list_for_each_entry_safe(req, temp_req, &req_list, list) {
518 		if (req->addr == addr) {
519 			req->status = -ECANCELED;
520 			req->timeout = jiffies;
521 			list_move(&req->list, &req_list);
522 			set_timeout(req->timeout);
523 			break;
524 		}
525 	}
526 	mutex_unlock(&lock);
527 }
528 EXPORT_SYMBOL(rdma_addr_cancel);
529 
530 struct resolve_cb_context {
531 	struct rdma_dev_addr *addr;
532 	struct completion comp;
533 };
534 
535 static void resolve_cb(int status, struct sockaddr *src_addr,
536 	     struct rdma_dev_addr *addr, void *context)
537 {
538 	memcpy(((struct resolve_cb_context *)context)->addr, addr, sizeof(struct
539 				rdma_dev_addr));
540 	complete(&((struct resolve_cb_context *)context)->comp);
541 }
542 
543 int rdma_addr_find_dmac_by_grh(const union ib_gid *sgid, const union ib_gid *dgid,
544 			       u8 *dmac, u16 *vlan_id, int *if_index)
545 {
546 	int ret = 0;
547 	struct rdma_dev_addr dev_addr;
548 	struct resolve_cb_context ctx;
549 	struct net_device *dev;
550 
551 	union {
552 		struct sockaddr     _sockaddr;
553 		struct sockaddr_in  _sockaddr_in;
554 		struct sockaddr_in6 _sockaddr_in6;
555 	} sgid_addr, dgid_addr;
556 
557 
558 	rdma_gid2ip(&sgid_addr._sockaddr, sgid);
559 	rdma_gid2ip(&dgid_addr._sockaddr, dgid);
560 
561 	memset(&dev_addr, 0, sizeof(dev_addr));
562 	if (if_index)
563 		dev_addr.bound_dev_if = *if_index;
564 	dev_addr.net = &init_net;
565 
566 	ctx.addr = &dev_addr;
567 	init_completion(&ctx.comp);
568 	ret = rdma_resolve_ip(&self, &sgid_addr._sockaddr, &dgid_addr._sockaddr,
569 			&dev_addr, 1000, resolve_cb, &ctx);
570 	if (ret)
571 		return ret;
572 
573 	wait_for_completion(&ctx.comp);
574 
575 	memcpy(dmac, dev_addr.dst_dev_addr, ETH_ALEN);
576 	dev = dev_get_by_index(&init_net, dev_addr.bound_dev_if);
577 	if (!dev)
578 		return -ENODEV;
579 	if (if_index)
580 		*if_index = dev_addr.bound_dev_if;
581 	if (vlan_id)
582 		*vlan_id = rdma_vlan_dev_vlan_id(dev);
583 	dev_put(dev);
584 	return ret;
585 }
586 EXPORT_SYMBOL(rdma_addr_find_dmac_by_grh);
587 
588 int rdma_addr_find_smac_by_sgid(union ib_gid *sgid, u8 *smac, u16 *vlan_id)
589 {
590 	int ret = 0;
591 	struct rdma_dev_addr dev_addr;
592 	union {
593 		struct sockaddr     _sockaddr;
594 		struct sockaddr_in  _sockaddr_in;
595 		struct sockaddr_in6 _sockaddr_in6;
596 	} gid_addr;
597 
598 	rdma_gid2ip(&gid_addr._sockaddr, sgid);
599 
600 	memset(&dev_addr, 0, sizeof(dev_addr));
601 	dev_addr.net = &init_net;
602 	ret = rdma_translate_ip(&gid_addr._sockaddr, &dev_addr, vlan_id);
603 	if (ret)
604 		return ret;
605 
606 	memcpy(smac, dev_addr.src_dev_addr, ETH_ALEN);
607 	return ret;
608 }
609 EXPORT_SYMBOL(rdma_addr_find_smac_by_sgid);
610 
611 static int netevent_callback(struct notifier_block *self, unsigned long event,
612 	void *ctx)
613 {
614 	if (event == NETEVENT_NEIGH_UPDATE) {
615 		struct neighbour *neigh = ctx;
616 
617 		if (neigh->nud_state & NUD_VALID) {
618 			set_timeout(jiffies);
619 		}
620 	}
621 	return 0;
622 }
623 
624 static struct notifier_block nb = {
625 	.notifier_call = netevent_callback
626 };
627 
628 static int __init addr_init(void)
629 {
630 	addr_wq = create_singlethread_workqueue("ib_addr");
631 	if (!addr_wq)
632 		return -ENOMEM;
633 
634 	register_netevent_notifier(&nb);
635 	rdma_addr_register_client(&self);
636 	return 0;
637 }
638 
639 static void __exit addr_cleanup(void)
640 {
641 	rdma_addr_unregister_client(&self);
642 	unregister_netevent_notifier(&nb);
643 	destroy_workqueue(addr_wq);
644 }
645 
646 module_init(addr_init);
647 module_exit(addr_cleanup);
648