xref: /openbmc/linux/drivers/infiniband/core/addr.c (revision abfbd895)
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(struct sockaddr *addr, struct rdma_dev_addr *dev_addr,
125 		      u16 *vlan_id)
126 {
127 	struct net_device *dev;
128 	int ret = -EADDRNOTAVAIL;
129 
130 	if (dev_addr->bound_dev_if) {
131 		dev = dev_get_by_index(dev_addr->net, dev_addr->bound_dev_if);
132 		if (!dev)
133 			return -ENODEV;
134 		ret = rdma_copy_addr(dev_addr, dev, NULL);
135 		dev_put(dev);
136 		return ret;
137 	}
138 
139 	switch (addr->sa_family) {
140 	case AF_INET:
141 		dev = ip_dev_find(dev_addr->net,
142 			((struct sockaddr_in *) addr)->sin_addr.s_addr);
143 
144 		if (!dev)
145 			return ret;
146 
147 		ret = rdma_copy_addr(dev_addr, dev, NULL);
148 		if (vlan_id)
149 			*vlan_id = rdma_vlan_dev_vlan_id(dev);
150 		dev_put(dev);
151 		break;
152 #if IS_ENABLED(CONFIG_IPV6)
153 	case AF_INET6:
154 		rcu_read_lock();
155 		for_each_netdev_rcu(dev_addr->net, dev) {
156 			if (ipv6_chk_addr(dev_addr->net,
157 					  &((struct sockaddr_in6 *) addr)->sin6_addr,
158 					  dev, 1)) {
159 				ret = rdma_copy_addr(dev_addr, dev, NULL);
160 				if (vlan_id)
161 					*vlan_id = rdma_vlan_dev_vlan_id(dev);
162 				break;
163 			}
164 		}
165 		rcu_read_unlock();
166 		break;
167 #endif
168 	}
169 	return ret;
170 }
171 EXPORT_SYMBOL(rdma_translate_ip);
172 
173 static void set_timeout(unsigned long time)
174 {
175 	unsigned long delay;
176 
177 	delay = time - jiffies;
178 	if ((long)delay < 0)
179 		delay = 0;
180 
181 	mod_delayed_work(addr_wq, &work, delay);
182 }
183 
184 static void queue_req(struct addr_req *req)
185 {
186 	struct addr_req *temp_req;
187 
188 	mutex_lock(&lock);
189 	list_for_each_entry_reverse(temp_req, &req_list, list) {
190 		if (time_after_eq(req->timeout, temp_req->timeout))
191 			break;
192 	}
193 
194 	list_add(&req->list, &temp_req->list);
195 
196 	if (req_list.next == &req->list)
197 		set_timeout(req->timeout);
198 	mutex_unlock(&lock);
199 }
200 
201 static int dst_fetch_ha(struct dst_entry *dst, struct rdma_dev_addr *dev_addr, void *daddr)
202 {
203 	struct neighbour *n;
204 	int ret;
205 
206 	n = dst_neigh_lookup(dst, daddr);
207 
208 	rcu_read_lock();
209 	if (!n || !(n->nud_state & NUD_VALID)) {
210 		if (n)
211 			neigh_event_send(n, NULL);
212 		ret = -ENODATA;
213 	} else {
214 		ret = rdma_copy_addr(dev_addr, dst->dev, n->ha);
215 	}
216 	rcu_read_unlock();
217 
218 	if (n)
219 		neigh_release(n);
220 
221 	return ret;
222 }
223 
224 static int addr4_resolve(struct sockaddr_in *src_in,
225 			 struct sockaddr_in *dst_in,
226 			 struct rdma_dev_addr *addr)
227 {
228 	__be32 src_ip = src_in->sin_addr.s_addr;
229 	__be32 dst_ip = dst_in->sin_addr.s_addr;
230 	struct rtable *rt;
231 	struct flowi4 fl4;
232 	int ret;
233 
234 	memset(&fl4, 0, sizeof(fl4));
235 	fl4.daddr = dst_ip;
236 	fl4.saddr = src_ip;
237 	fl4.flowi4_oif = addr->bound_dev_if;
238 	rt = ip_route_output_key(addr->net, &fl4);
239 	if (IS_ERR(rt)) {
240 		ret = PTR_ERR(rt);
241 		goto out;
242 	}
243 	src_in->sin_family = AF_INET;
244 	src_in->sin_addr.s_addr = fl4.saddr;
245 
246 	if (rt->dst.dev->flags & IFF_LOOPBACK) {
247 		ret = rdma_translate_ip((struct sockaddr *)dst_in, addr, NULL);
248 		if (!ret)
249 			memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
250 		goto put;
251 	}
252 
253 	/* If the device does ARP internally, return 'done' */
254 	if (rt->dst.dev->flags & IFF_NOARP) {
255 		ret = rdma_copy_addr(addr, rt->dst.dev, NULL);
256 		goto put;
257 	}
258 
259 	ret = dst_fetch_ha(&rt->dst, addr, &fl4.daddr);
260 put:
261 	ip_rt_put(rt);
262 out:
263 	return ret;
264 }
265 
266 #if IS_ENABLED(CONFIG_IPV6)
267 static int addr6_resolve(struct sockaddr_in6 *src_in,
268 			 struct sockaddr_in6 *dst_in,
269 			 struct rdma_dev_addr *addr)
270 {
271 	struct flowi6 fl6;
272 	struct dst_entry *dst;
273 	int ret;
274 
275 	memset(&fl6, 0, sizeof fl6);
276 	fl6.daddr = dst_in->sin6_addr;
277 	fl6.saddr = src_in->sin6_addr;
278 	fl6.flowi6_oif = addr->bound_dev_if;
279 
280 	dst = ip6_route_output(addr->net, NULL, &fl6);
281 	if ((ret = dst->error))
282 		goto put;
283 
284 	if (ipv6_addr_any(&fl6.saddr)) {
285 		ret = ipv6_dev_get_saddr(addr->net, ip6_dst_idev(dst)->dev,
286 					 &fl6.daddr, 0, &fl6.saddr);
287 		if (ret)
288 			goto put;
289 
290 		src_in->sin6_family = AF_INET6;
291 		src_in->sin6_addr = fl6.saddr;
292 	}
293 
294 	if (dst->dev->flags & IFF_LOOPBACK) {
295 		ret = rdma_translate_ip((struct sockaddr *)dst_in, addr, NULL);
296 		if (!ret)
297 			memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
298 		goto put;
299 	}
300 
301 	/* If the device does ARP internally, return 'done' */
302 	if (dst->dev->flags & IFF_NOARP) {
303 		ret = rdma_copy_addr(addr, dst->dev, NULL);
304 		goto put;
305 	}
306 
307 	ret = dst_fetch_ha(dst, addr, &fl6.daddr);
308 put:
309 	dst_release(dst);
310 	return ret;
311 }
312 #else
313 static int addr6_resolve(struct sockaddr_in6 *src_in,
314 			 struct sockaddr_in6 *dst_in,
315 			 struct rdma_dev_addr *addr)
316 {
317 	return -EADDRNOTAVAIL;
318 }
319 #endif
320 
321 static int addr_resolve(struct sockaddr *src_in,
322 			struct sockaddr *dst_in,
323 			struct rdma_dev_addr *addr)
324 {
325 	if (src_in->sa_family == AF_INET) {
326 		return addr4_resolve((struct sockaddr_in *) src_in,
327 			(struct sockaddr_in *) dst_in, addr);
328 	} else
329 		return addr6_resolve((struct sockaddr_in6 *) src_in,
330 			(struct sockaddr_in6 *) dst_in, addr);
331 }
332 
333 static void process_req(struct work_struct *work)
334 {
335 	struct addr_req *req, *temp_req;
336 	struct sockaddr *src_in, *dst_in;
337 	struct list_head done_list;
338 
339 	INIT_LIST_HEAD(&done_list);
340 
341 	mutex_lock(&lock);
342 	list_for_each_entry_safe(req, temp_req, &req_list, list) {
343 		if (req->status == -ENODATA) {
344 			src_in = (struct sockaddr *) &req->src_addr;
345 			dst_in = (struct sockaddr *) &req->dst_addr;
346 			req->status = addr_resolve(src_in, dst_in, req->addr);
347 			if (req->status && time_after_eq(jiffies, req->timeout))
348 				req->status = -ETIMEDOUT;
349 			else if (req->status == -ENODATA)
350 				continue;
351 		}
352 		list_move_tail(&req->list, &done_list);
353 	}
354 
355 	if (!list_empty(&req_list)) {
356 		req = list_entry(req_list.next, struct addr_req, list);
357 		set_timeout(req->timeout);
358 	}
359 	mutex_unlock(&lock);
360 
361 	list_for_each_entry_safe(req, temp_req, &done_list, list) {
362 		list_del(&req->list);
363 		req->callback(req->status, (struct sockaddr *) &req->src_addr,
364 			req->addr, req->context);
365 		put_client(req->client);
366 		kfree(req);
367 	}
368 }
369 
370 int rdma_resolve_ip(struct rdma_addr_client *client,
371 		    struct sockaddr *src_addr, struct sockaddr *dst_addr,
372 		    struct rdma_dev_addr *addr, int timeout_ms,
373 		    void (*callback)(int status, struct sockaddr *src_addr,
374 				     struct rdma_dev_addr *addr, void *context),
375 		    void *context)
376 {
377 	struct sockaddr *src_in, *dst_in;
378 	struct addr_req *req;
379 	int ret = 0;
380 
381 	req = kzalloc(sizeof *req, GFP_KERNEL);
382 	if (!req)
383 		return -ENOMEM;
384 
385 	src_in = (struct sockaddr *) &req->src_addr;
386 	dst_in = (struct sockaddr *) &req->dst_addr;
387 
388 	if (src_addr) {
389 		if (src_addr->sa_family != dst_addr->sa_family) {
390 			ret = -EINVAL;
391 			goto err;
392 		}
393 
394 		memcpy(src_in, src_addr, rdma_addr_size(src_addr));
395 	} else {
396 		src_in->sa_family = dst_addr->sa_family;
397 	}
398 
399 	memcpy(dst_in, dst_addr, rdma_addr_size(dst_addr));
400 	req->addr = addr;
401 	req->callback = callback;
402 	req->context = context;
403 	req->client = client;
404 	atomic_inc(&client->refcount);
405 
406 	req->status = addr_resolve(src_in, dst_in, addr);
407 	switch (req->status) {
408 	case 0:
409 		req->timeout = jiffies;
410 		queue_req(req);
411 		break;
412 	case -ENODATA:
413 		req->timeout = msecs_to_jiffies(timeout_ms) + jiffies;
414 		queue_req(req);
415 		break;
416 	default:
417 		ret = req->status;
418 		atomic_dec(&client->refcount);
419 		goto err;
420 	}
421 	return ret;
422 err:
423 	kfree(req);
424 	return ret;
425 }
426 EXPORT_SYMBOL(rdma_resolve_ip);
427 
428 void rdma_addr_cancel(struct rdma_dev_addr *addr)
429 {
430 	struct addr_req *req, *temp_req;
431 
432 	mutex_lock(&lock);
433 	list_for_each_entry_safe(req, temp_req, &req_list, list) {
434 		if (req->addr == addr) {
435 			req->status = -ECANCELED;
436 			req->timeout = jiffies;
437 			list_move(&req->list, &req_list);
438 			set_timeout(req->timeout);
439 			break;
440 		}
441 	}
442 	mutex_unlock(&lock);
443 }
444 EXPORT_SYMBOL(rdma_addr_cancel);
445 
446 struct resolve_cb_context {
447 	struct rdma_dev_addr *addr;
448 	struct completion comp;
449 };
450 
451 static void resolve_cb(int status, struct sockaddr *src_addr,
452 	     struct rdma_dev_addr *addr, void *context)
453 {
454 	memcpy(((struct resolve_cb_context *)context)->addr, addr, sizeof(struct
455 				rdma_dev_addr));
456 	complete(&((struct resolve_cb_context *)context)->comp);
457 }
458 
459 int rdma_addr_find_dmac_by_grh(const union ib_gid *sgid, const union ib_gid *dgid,
460 			       u8 *dmac, u16 *vlan_id, int if_index)
461 {
462 	int ret = 0;
463 	struct rdma_dev_addr dev_addr;
464 	struct resolve_cb_context ctx;
465 	struct net_device *dev;
466 
467 	union {
468 		struct sockaddr     _sockaddr;
469 		struct sockaddr_in  _sockaddr_in;
470 		struct sockaddr_in6 _sockaddr_in6;
471 	} sgid_addr, dgid_addr;
472 
473 
474 	rdma_gid2ip(&sgid_addr._sockaddr, sgid);
475 	rdma_gid2ip(&dgid_addr._sockaddr, dgid);
476 
477 	memset(&dev_addr, 0, sizeof(dev_addr));
478 	dev_addr.bound_dev_if = if_index;
479 	dev_addr.net = &init_net;
480 
481 	ctx.addr = &dev_addr;
482 	init_completion(&ctx.comp);
483 	ret = rdma_resolve_ip(&self, &sgid_addr._sockaddr, &dgid_addr._sockaddr,
484 			&dev_addr, 1000, resolve_cb, &ctx);
485 	if (ret)
486 		return ret;
487 
488 	wait_for_completion(&ctx.comp);
489 
490 	memcpy(dmac, dev_addr.dst_dev_addr, ETH_ALEN);
491 	dev = dev_get_by_index(&init_net, dev_addr.bound_dev_if);
492 	if (!dev)
493 		return -ENODEV;
494 	if (vlan_id)
495 		*vlan_id = rdma_vlan_dev_vlan_id(dev);
496 	dev_put(dev);
497 	return ret;
498 }
499 EXPORT_SYMBOL(rdma_addr_find_dmac_by_grh);
500 
501 int rdma_addr_find_smac_by_sgid(union ib_gid *sgid, u8 *smac, u16 *vlan_id)
502 {
503 	int ret = 0;
504 	struct rdma_dev_addr dev_addr;
505 	union {
506 		struct sockaddr     _sockaddr;
507 		struct sockaddr_in  _sockaddr_in;
508 		struct sockaddr_in6 _sockaddr_in6;
509 	} gid_addr;
510 
511 	rdma_gid2ip(&gid_addr._sockaddr, sgid);
512 
513 	memset(&dev_addr, 0, sizeof(dev_addr));
514 	dev_addr.net = &init_net;
515 	ret = rdma_translate_ip(&gid_addr._sockaddr, &dev_addr, vlan_id);
516 	if (ret)
517 		return ret;
518 
519 	memcpy(smac, dev_addr.src_dev_addr, ETH_ALEN);
520 	return ret;
521 }
522 EXPORT_SYMBOL(rdma_addr_find_smac_by_sgid);
523 
524 static int netevent_callback(struct notifier_block *self, unsigned long event,
525 	void *ctx)
526 {
527 	if (event == NETEVENT_NEIGH_UPDATE) {
528 		struct neighbour *neigh = ctx;
529 
530 		if (neigh->nud_state & NUD_VALID) {
531 			set_timeout(jiffies);
532 		}
533 	}
534 	return 0;
535 }
536 
537 static struct notifier_block nb = {
538 	.notifier_call = netevent_callback
539 };
540 
541 static int __init addr_init(void)
542 {
543 	addr_wq = create_singlethread_workqueue("ib_addr");
544 	if (!addr_wq)
545 		return -ENOMEM;
546 
547 	register_netevent_notifier(&nb);
548 	rdma_addr_register_client(&self);
549 	return 0;
550 }
551 
552 static void __exit addr_cleanup(void)
553 {
554 	rdma_addr_unregister_client(&self);
555 	unregister_netevent_notifier(&nb);
556 	destroy_workqueue(addr_wq);
557 }
558 
559 module_init(addr_init);
560 module_exit(addr_cleanup);
561