xref: /openbmc/linux/drivers/infiniband/core/addr.c (revision 95e9fd10)
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 IS_ENABLED(CONFIG_IPV6)
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 dst_fetch_ha(struct dst_entry *dst, struct rdma_dev_addr *dev_addr, void *daddr)
182 {
183 	struct neighbour *n;
184 	int ret;
185 
186 	n = dst_neigh_lookup(dst, daddr);
187 
188 	rcu_read_lock();
189 	if (!n || !(n->nud_state & NUD_VALID)) {
190 		if (n)
191 			neigh_event_send(n, NULL);
192 		ret = -ENODATA;
193 	} else {
194 		ret = rdma_copy_addr(dev_addr, dst->dev, n->ha);
195 	}
196 	rcu_read_unlock();
197 
198 	if (n)
199 		neigh_release(n);
200 
201 	return ret;
202 }
203 
204 static int addr4_resolve(struct sockaddr_in *src_in,
205 			 struct sockaddr_in *dst_in,
206 			 struct rdma_dev_addr *addr)
207 {
208 	__be32 src_ip = src_in->sin_addr.s_addr;
209 	__be32 dst_ip = dst_in->sin_addr.s_addr;
210 	struct rtable *rt;
211 	struct flowi4 fl4;
212 	int ret;
213 
214 	memset(&fl4, 0, sizeof(fl4));
215 	fl4.daddr = dst_ip;
216 	fl4.saddr = src_ip;
217 	fl4.flowi4_oif = addr->bound_dev_if;
218 	rt = ip_route_output_key(&init_net, &fl4);
219 	if (IS_ERR(rt)) {
220 		ret = PTR_ERR(rt);
221 		goto out;
222 	}
223 	src_in->sin_family = AF_INET;
224 	src_in->sin_addr.s_addr = fl4.saddr;
225 
226 	if (rt->dst.dev->flags & IFF_LOOPBACK) {
227 		ret = rdma_translate_ip((struct sockaddr *) dst_in, addr);
228 		if (!ret)
229 			memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
230 		goto put;
231 	}
232 
233 	/* If the device does ARP internally, return 'done' */
234 	if (rt->dst.dev->flags & IFF_NOARP) {
235 		ret = rdma_copy_addr(addr, rt->dst.dev, NULL);
236 		goto put;
237 	}
238 
239 	ret = dst_fetch_ha(&rt->dst, addr, &fl4.daddr);
240 put:
241 	ip_rt_put(rt);
242 out:
243 	return ret;
244 }
245 
246 #if IS_ENABLED(CONFIG_IPV6)
247 static int addr6_resolve(struct sockaddr_in6 *src_in,
248 			 struct sockaddr_in6 *dst_in,
249 			 struct rdma_dev_addr *addr)
250 {
251 	struct flowi6 fl6;
252 	struct dst_entry *dst;
253 	int ret;
254 
255 	memset(&fl6, 0, sizeof fl6);
256 	fl6.daddr = dst_in->sin6_addr;
257 	fl6.saddr = src_in->sin6_addr;
258 	fl6.flowi6_oif = addr->bound_dev_if;
259 
260 	dst = ip6_route_output(&init_net, NULL, &fl6);
261 	if ((ret = dst->error))
262 		goto put;
263 
264 	if (ipv6_addr_any(&fl6.saddr)) {
265 		ret = ipv6_dev_get_saddr(&init_net, ip6_dst_idev(dst)->dev,
266 					 &fl6.daddr, 0, &fl6.saddr);
267 		if (ret)
268 			goto put;
269 
270 		src_in->sin6_family = AF_INET6;
271 		src_in->sin6_addr = fl6.saddr;
272 	}
273 
274 	if (dst->dev->flags & IFF_LOOPBACK) {
275 		ret = rdma_translate_ip((struct sockaddr *) dst_in, addr);
276 		if (!ret)
277 			memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
278 		goto put;
279 	}
280 
281 	/* If the device does ARP internally, return 'done' */
282 	if (dst->dev->flags & IFF_NOARP) {
283 		ret = rdma_copy_addr(addr, dst->dev, NULL);
284 		goto put;
285 	}
286 
287 	ret = dst_fetch_ha(dst, addr, &fl6.daddr);
288 put:
289 	dst_release(dst);
290 	return ret;
291 }
292 #else
293 static int addr6_resolve(struct sockaddr_in6 *src_in,
294 			 struct sockaddr_in6 *dst_in,
295 			 struct rdma_dev_addr *addr)
296 {
297 	return -EADDRNOTAVAIL;
298 }
299 #endif
300 
301 static int addr_resolve(struct sockaddr *src_in,
302 			struct sockaddr *dst_in,
303 			struct rdma_dev_addr *addr)
304 {
305 	if (src_in->sa_family == AF_INET) {
306 		return addr4_resolve((struct sockaddr_in *) src_in,
307 			(struct sockaddr_in *) dst_in, addr);
308 	} else
309 		return addr6_resolve((struct sockaddr_in6 *) src_in,
310 			(struct sockaddr_in6 *) dst_in, addr);
311 }
312 
313 static void process_req(struct work_struct *work)
314 {
315 	struct addr_req *req, *temp_req;
316 	struct sockaddr *src_in, *dst_in;
317 	struct list_head done_list;
318 
319 	INIT_LIST_HEAD(&done_list);
320 
321 	mutex_lock(&lock);
322 	list_for_each_entry_safe(req, temp_req, &req_list, list) {
323 		if (req->status == -ENODATA) {
324 			src_in = (struct sockaddr *) &req->src_addr;
325 			dst_in = (struct sockaddr *) &req->dst_addr;
326 			req->status = addr_resolve(src_in, dst_in, req->addr);
327 			if (req->status && time_after_eq(jiffies, req->timeout))
328 				req->status = -ETIMEDOUT;
329 			else if (req->status == -ENODATA)
330 				continue;
331 		}
332 		list_move_tail(&req->list, &done_list);
333 	}
334 
335 	if (!list_empty(&req_list)) {
336 		req = list_entry(req_list.next, struct addr_req, list);
337 		set_timeout(req->timeout);
338 	}
339 	mutex_unlock(&lock);
340 
341 	list_for_each_entry_safe(req, temp_req, &done_list, list) {
342 		list_del(&req->list);
343 		req->callback(req->status, (struct sockaddr *) &req->src_addr,
344 			req->addr, req->context);
345 		put_client(req->client);
346 		kfree(req);
347 	}
348 }
349 
350 int rdma_resolve_ip(struct rdma_addr_client *client,
351 		    struct sockaddr *src_addr, struct sockaddr *dst_addr,
352 		    struct rdma_dev_addr *addr, int timeout_ms,
353 		    void (*callback)(int status, struct sockaddr *src_addr,
354 				     struct rdma_dev_addr *addr, void *context),
355 		    void *context)
356 {
357 	struct sockaddr *src_in, *dst_in;
358 	struct addr_req *req;
359 	int ret = 0;
360 
361 	req = kzalloc(sizeof *req, GFP_KERNEL);
362 	if (!req)
363 		return -ENOMEM;
364 
365 	src_in = (struct sockaddr *) &req->src_addr;
366 	dst_in = (struct sockaddr *) &req->dst_addr;
367 
368 	if (src_addr) {
369 		if (src_addr->sa_family != dst_addr->sa_family) {
370 			ret = -EINVAL;
371 			goto err;
372 		}
373 
374 		memcpy(src_in, src_addr, ip_addr_size(src_addr));
375 	} else {
376 		src_in->sa_family = dst_addr->sa_family;
377 	}
378 
379 	memcpy(dst_in, dst_addr, ip_addr_size(dst_addr));
380 	req->addr = addr;
381 	req->callback = callback;
382 	req->context = context;
383 	req->client = client;
384 	atomic_inc(&client->refcount);
385 
386 	req->status = addr_resolve(src_in, dst_in, addr);
387 	switch (req->status) {
388 	case 0:
389 		req->timeout = jiffies;
390 		queue_req(req);
391 		break;
392 	case -ENODATA:
393 		req->timeout = msecs_to_jiffies(timeout_ms) + jiffies;
394 		queue_req(req);
395 		break;
396 	default:
397 		ret = req->status;
398 		atomic_dec(&client->refcount);
399 		goto err;
400 	}
401 	return ret;
402 err:
403 	kfree(req);
404 	return ret;
405 }
406 EXPORT_SYMBOL(rdma_resolve_ip);
407 
408 void rdma_addr_cancel(struct rdma_dev_addr *addr)
409 {
410 	struct addr_req *req, *temp_req;
411 
412 	mutex_lock(&lock);
413 	list_for_each_entry_safe(req, temp_req, &req_list, list) {
414 		if (req->addr == addr) {
415 			req->status = -ECANCELED;
416 			req->timeout = jiffies;
417 			list_move(&req->list, &req_list);
418 			set_timeout(req->timeout);
419 			break;
420 		}
421 	}
422 	mutex_unlock(&lock);
423 }
424 EXPORT_SYMBOL(rdma_addr_cancel);
425 
426 static int netevent_callback(struct notifier_block *self, unsigned long event,
427 	void *ctx)
428 {
429 	if (event == NETEVENT_NEIGH_UPDATE) {
430 		struct neighbour *neigh = ctx;
431 
432 		if (neigh->nud_state & NUD_VALID) {
433 			set_timeout(jiffies);
434 		}
435 	}
436 	return 0;
437 }
438 
439 static struct notifier_block nb = {
440 	.notifier_call = netevent_callback
441 };
442 
443 static int __init addr_init(void)
444 {
445 	addr_wq = create_singlethread_workqueue("ib_addr");
446 	if (!addr_wq)
447 		return -ENOMEM;
448 
449 	register_netevent_notifier(&nb);
450 	return 0;
451 }
452 
453 static void __exit addr_cleanup(void)
454 {
455 	unregister_netevent_notifier(&nb);
456 	destroy_workqueue(addr_wq);
457 }
458 
459 module_init(addr_init);
460 module_exit(addr_cleanup);
461