xref: /linux/drivers/infiniband/core/addr.c (revision 44b111b519160e33fdc41eadb39af86a24707edf)
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 
49 MODULE_AUTHOR("Sean Hefty");
50 MODULE_DESCRIPTION("IB Address Translation");
51 MODULE_LICENSE("Dual BSD/GPL");
52 
53 struct addr_req {
54 	struct list_head list;
55 	struct sockaddr_storage src_addr;
56 	struct sockaddr_storage dst_addr;
57 	struct rdma_dev_addr *addr;
58 	struct rdma_addr_client *client;
59 	void *context;
60 	void (*callback)(int status, struct sockaddr *src_addr,
61 			 struct rdma_dev_addr *addr, void *context);
62 	unsigned long timeout;
63 	int status;
64 };
65 
66 static void process_req(struct work_struct *work);
67 
68 static DEFINE_MUTEX(lock);
69 static LIST_HEAD(req_list);
70 static DECLARE_DELAYED_WORK(work, process_req);
71 static struct workqueue_struct *addr_wq;
72 
73 void rdma_addr_register_client(struct rdma_addr_client *client)
74 {
75 	atomic_set(&client->refcount, 1);
76 	init_completion(&client->comp);
77 }
78 EXPORT_SYMBOL(rdma_addr_register_client);
79 
80 static inline void put_client(struct rdma_addr_client *client)
81 {
82 	if (atomic_dec_and_test(&client->refcount))
83 		complete(&client->comp);
84 }
85 
86 void rdma_addr_unregister_client(struct rdma_addr_client *client)
87 {
88 	put_client(client);
89 	wait_for_completion(&client->comp);
90 }
91 EXPORT_SYMBOL(rdma_addr_unregister_client);
92 
93 int rdma_copy_addr(struct rdma_dev_addr *dev_addr, struct net_device *dev,
94 		     const unsigned char *dst_dev_addr)
95 {
96 	dev_addr->dev_type = dev->type;
97 	memcpy(dev_addr->src_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
98 	memcpy(dev_addr->broadcast, dev->broadcast, MAX_ADDR_LEN);
99 	if (dst_dev_addr)
100 		memcpy(dev_addr->dst_dev_addr, dst_dev_addr, MAX_ADDR_LEN);
101 	dev_addr->bound_dev_if = dev->ifindex;
102 	return 0;
103 }
104 EXPORT_SYMBOL(rdma_copy_addr);
105 
106 int rdma_translate_ip(struct sockaddr *addr, struct rdma_dev_addr *dev_addr)
107 {
108 	struct net_device *dev;
109 	int ret = -EADDRNOTAVAIL;
110 
111 	if (dev_addr->bound_dev_if) {
112 		dev = dev_get_by_index(&init_net, dev_addr->bound_dev_if);
113 		if (!dev)
114 			return -ENODEV;
115 		ret = rdma_copy_addr(dev_addr, dev, NULL);
116 		dev_put(dev);
117 		return ret;
118 	}
119 
120 	switch (addr->sa_family) {
121 	case AF_INET:
122 		dev = ip_dev_find(&init_net,
123 			((struct sockaddr_in *) addr)->sin_addr.s_addr);
124 
125 		if (!dev)
126 			return ret;
127 
128 		ret = rdma_copy_addr(dev_addr, dev, NULL);
129 		dev_put(dev);
130 		break;
131 
132 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
133 	case AF_INET6:
134 		rcu_read_lock();
135 		for_each_netdev_rcu(&init_net, dev) {
136 			if (ipv6_chk_addr(&init_net,
137 					  &((struct sockaddr_in6 *) addr)->sin6_addr,
138 					  dev, 1)) {
139 				ret = rdma_copy_addr(dev_addr, dev, NULL);
140 				break;
141 			}
142 		}
143 		rcu_read_unlock();
144 		break;
145 #endif
146 	}
147 	return ret;
148 }
149 EXPORT_SYMBOL(rdma_translate_ip);
150 
151 static void set_timeout(unsigned long time)
152 {
153 	unsigned long delay;
154 
155 	cancel_delayed_work(&work);
156 
157 	delay = time - jiffies;
158 	if ((long)delay <= 0)
159 		delay = 1;
160 
161 	queue_delayed_work(addr_wq, &work, delay);
162 }
163 
164 static void queue_req(struct addr_req *req)
165 {
166 	struct addr_req *temp_req;
167 
168 	mutex_lock(&lock);
169 	list_for_each_entry_reverse(temp_req, &req_list, list) {
170 		if (time_after_eq(req->timeout, temp_req->timeout))
171 			break;
172 	}
173 
174 	list_add(&req->list, &temp_req->list);
175 
176 	if (req_list.next == &req->list)
177 		set_timeout(req->timeout);
178 	mutex_unlock(&lock);
179 }
180 
181 static int addr4_resolve(struct sockaddr_in *src_in,
182 			 struct sockaddr_in *dst_in,
183 			 struct rdma_dev_addr *addr)
184 {
185 	__be32 src_ip = src_in->sin_addr.s_addr;
186 	__be32 dst_ip = dst_in->sin_addr.s_addr;
187 	struct rtable *rt;
188 	struct neighbour *neigh;
189 	struct flowi4 fl4;
190 	int ret;
191 
192 	memset(&fl4, 0, sizeof(fl4));
193 	fl4.daddr = dst_ip;
194 	fl4.saddr = src_ip;
195 	fl4.flowi4_oif = addr->bound_dev_if;
196 	rt = ip_route_output_key(&init_net, &fl4);
197 	if (IS_ERR(rt)) {
198 		ret = PTR_ERR(rt);
199 		goto out;
200 	}
201 	src_in->sin_family = AF_INET;
202 	src_in->sin_addr.s_addr = fl4.saddr;
203 
204 	if (rt->dst.dev->flags & IFF_LOOPBACK) {
205 		ret = rdma_translate_ip((struct sockaddr *) dst_in, addr);
206 		if (!ret)
207 			memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
208 		goto put;
209 	}
210 
211 	/* If the device does ARP internally, return 'done' */
212 	if (rt->dst.dev->flags & IFF_NOARP) {
213 		ret = rdma_copy_addr(addr, rt->dst.dev, NULL);
214 		goto put;
215 	}
216 
217 	neigh = neigh_lookup(&arp_tbl, &rt->rt_gateway, rt->dst.dev);
218 	if (!neigh || !(neigh->nud_state & NUD_VALID)) {
219 		rcu_read_lock();
220 		neigh_event_send(dst_get_neighbour(&rt->dst), NULL);
221 		rcu_read_unlock();
222 		ret = -ENODATA;
223 		if (neigh)
224 			goto release;
225 		goto put;
226 	}
227 
228 	ret = rdma_copy_addr(addr, neigh->dev, neigh->ha);
229 release:
230 	neigh_release(neigh);
231 put:
232 	ip_rt_put(rt);
233 out:
234 	return ret;
235 }
236 
237 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
238 static int addr6_resolve(struct sockaddr_in6 *src_in,
239 			 struct sockaddr_in6 *dst_in,
240 			 struct rdma_dev_addr *addr)
241 {
242 	struct flowi6 fl6;
243 	struct neighbour *neigh;
244 	struct dst_entry *dst;
245 	int ret;
246 
247 	memset(&fl6, 0, sizeof fl6);
248 	ipv6_addr_copy(&fl6.daddr, &dst_in->sin6_addr);
249 	ipv6_addr_copy(&fl6.saddr, &src_in->sin6_addr);
250 	fl6.flowi6_oif = addr->bound_dev_if;
251 
252 	dst = ip6_route_output(&init_net, NULL, &fl6);
253 	if ((ret = dst->error))
254 		goto put;
255 
256 	if (ipv6_addr_any(&fl6.saddr)) {
257 		ret = ipv6_dev_get_saddr(&init_net, ip6_dst_idev(dst)->dev,
258 					 &fl6.daddr, 0, &fl6.saddr);
259 		if (ret)
260 			goto put;
261 
262 		src_in->sin6_family = AF_INET6;
263 		ipv6_addr_copy(&src_in->sin6_addr, &fl6.saddr);
264 	}
265 
266 	if (dst->dev->flags & IFF_LOOPBACK) {
267 		ret = rdma_translate_ip((struct sockaddr *) dst_in, addr);
268 		if (!ret)
269 			memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
270 		goto put;
271 	}
272 
273 	/* If the device does ARP internally, return 'done' */
274 	if (dst->dev->flags & IFF_NOARP) {
275 		ret = rdma_copy_addr(addr, dst->dev, NULL);
276 		goto put;
277 	}
278 
279 	rcu_read_lock();
280 	neigh = dst_get_neighbour(dst);
281 	if (!neigh || !(neigh->nud_state & NUD_VALID)) {
282 		if (neigh)
283 			neigh_event_send(neigh, NULL);
284 		ret = -ENODATA;
285 	} else {
286 		ret = rdma_copy_addr(addr, dst->dev, neigh->ha);
287 	}
288 	rcu_read_unlock();
289 put:
290 	dst_release(dst);
291 	return ret;
292 }
293 #else
294 static int addr6_resolve(struct sockaddr_in6 *src_in,
295 			 struct sockaddr_in6 *dst_in,
296 			 struct rdma_dev_addr *addr)
297 {
298 	return -EADDRNOTAVAIL;
299 }
300 #endif
301 
302 static int addr_resolve(struct sockaddr *src_in,
303 			struct sockaddr *dst_in,
304 			struct rdma_dev_addr *addr)
305 {
306 	if (src_in->sa_family == AF_INET) {
307 		return addr4_resolve((struct sockaddr_in *) src_in,
308 			(struct sockaddr_in *) dst_in, addr);
309 	} else
310 		return addr6_resolve((struct sockaddr_in6 *) src_in,
311 			(struct sockaddr_in6 *) dst_in, addr);
312 }
313 
314 static void process_req(struct work_struct *work)
315 {
316 	struct addr_req *req, *temp_req;
317 	struct sockaddr *src_in, *dst_in;
318 	struct list_head done_list;
319 
320 	INIT_LIST_HEAD(&done_list);
321 
322 	mutex_lock(&lock);
323 	list_for_each_entry_safe(req, temp_req, &req_list, list) {
324 		if (req->status == -ENODATA) {
325 			src_in = (struct sockaddr *) &req->src_addr;
326 			dst_in = (struct sockaddr *) &req->dst_addr;
327 			req->status = addr_resolve(src_in, dst_in, req->addr);
328 			if (req->status && time_after_eq(jiffies, req->timeout))
329 				req->status = -ETIMEDOUT;
330 			else if (req->status == -ENODATA)
331 				continue;
332 		}
333 		list_move_tail(&req->list, &done_list);
334 	}
335 
336 	if (!list_empty(&req_list)) {
337 		req = list_entry(req_list.next, struct addr_req, list);
338 		set_timeout(req->timeout);
339 	}
340 	mutex_unlock(&lock);
341 
342 	list_for_each_entry_safe(req, temp_req, &done_list, list) {
343 		list_del(&req->list);
344 		req->callback(req->status, (struct sockaddr *) &req->src_addr,
345 			req->addr, req->context);
346 		put_client(req->client);
347 		kfree(req);
348 	}
349 }
350 
351 int rdma_resolve_ip(struct rdma_addr_client *client,
352 		    struct sockaddr *src_addr, struct sockaddr *dst_addr,
353 		    struct rdma_dev_addr *addr, int timeout_ms,
354 		    void (*callback)(int status, struct sockaddr *src_addr,
355 				     struct rdma_dev_addr *addr, void *context),
356 		    void *context)
357 {
358 	struct sockaddr *src_in, *dst_in;
359 	struct addr_req *req;
360 	int ret = 0;
361 
362 	req = kzalloc(sizeof *req, GFP_KERNEL);
363 	if (!req)
364 		return -ENOMEM;
365 
366 	src_in = (struct sockaddr *) &req->src_addr;
367 	dst_in = (struct sockaddr *) &req->dst_addr;
368 
369 	if (src_addr) {
370 		if (src_addr->sa_family != dst_addr->sa_family) {
371 			ret = -EINVAL;
372 			goto err;
373 		}
374 
375 		memcpy(src_in, src_addr, ip_addr_size(src_addr));
376 	} else {
377 		src_in->sa_family = dst_addr->sa_family;
378 	}
379 
380 	memcpy(dst_in, dst_addr, ip_addr_size(dst_addr));
381 	req->addr = addr;
382 	req->callback = callback;
383 	req->context = context;
384 	req->client = client;
385 	atomic_inc(&client->refcount);
386 
387 	req->status = addr_resolve(src_in, dst_in, addr);
388 	switch (req->status) {
389 	case 0:
390 		req->timeout = jiffies;
391 		queue_req(req);
392 		break;
393 	case -ENODATA:
394 		req->timeout = msecs_to_jiffies(timeout_ms) + jiffies;
395 		queue_req(req);
396 		break;
397 	default:
398 		ret = req->status;
399 		atomic_dec(&client->refcount);
400 		goto err;
401 	}
402 	return ret;
403 err:
404 	kfree(req);
405 	return ret;
406 }
407 EXPORT_SYMBOL(rdma_resolve_ip);
408 
409 void rdma_addr_cancel(struct rdma_dev_addr *addr)
410 {
411 	struct addr_req *req, *temp_req;
412 
413 	mutex_lock(&lock);
414 	list_for_each_entry_safe(req, temp_req, &req_list, list) {
415 		if (req->addr == addr) {
416 			req->status = -ECANCELED;
417 			req->timeout = jiffies;
418 			list_move(&req->list, &req_list);
419 			set_timeout(req->timeout);
420 			break;
421 		}
422 	}
423 	mutex_unlock(&lock);
424 }
425 EXPORT_SYMBOL(rdma_addr_cancel);
426 
427 static int netevent_callback(struct notifier_block *self, unsigned long event,
428 	void *ctx)
429 {
430 	if (event == NETEVENT_NEIGH_UPDATE) {
431 		struct neighbour *neigh = ctx;
432 
433 		if (neigh->nud_state & NUD_VALID) {
434 			set_timeout(jiffies);
435 		}
436 	}
437 	return 0;
438 }
439 
440 static struct notifier_block nb = {
441 	.notifier_call = netevent_callback
442 };
443 
444 static int __init addr_init(void)
445 {
446 	addr_wq = create_singlethread_workqueue("ib_addr");
447 	if (!addr_wq)
448 		return -ENOMEM;
449 
450 	register_netevent_notifier(&nb);
451 	return 0;
452 }
453 
454 static void __exit addr_cleanup(void)
455 {
456 	unregister_netevent_notifier(&nb);
457 	destroy_workqueue(addr_wq);
458 }
459 
460 module_init(addr_init);
461 module_exit(addr_cleanup);
462