xref: /openbmc/linux/drivers/infiniband/core/addr.c (revision 54cbac81)
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 	delay = time - jiffies;
156 	if ((long)delay <= 0)
157 		delay = 1;
158 
159 	mod_delayed_work(addr_wq, &work, delay);
160 }
161 
162 static void queue_req(struct addr_req *req)
163 {
164 	struct addr_req *temp_req;
165 
166 	mutex_lock(&lock);
167 	list_for_each_entry_reverse(temp_req, &req_list, list) {
168 		if (time_after_eq(req->timeout, temp_req->timeout))
169 			break;
170 	}
171 
172 	list_add(&req->list, &temp_req->list);
173 
174 	if (req_list.next == &req->list)
175 		set_timeout(req->timeout);
176 	mutex_unlock(&lock);
177 }
178 
179 static int dst_fetch_ha(struct dst_entry *dst, struct rdma_dev_addr *dev_addr, void *daddr)
180 {
181 	struct neighbour *n;
182 	int ret;
183 
184 	n = dst_neigh_lookup(dst, daddr);
185 
186 	rcu_read_lock();
187 	if (!n || !(n->nud_state & NUD_VALID)) {
188 		if (n)
189 			neigh_event_send(n, NULL);
190 		ret = -ENODATA;
191 	} else {
192 		ret = rdma_copy_addr(dev_addr, dst->dev, n->ha);
193 	}
194 	rcu_read_unlock();
195 
196 	if (n)
197 		neigh_release(n);
198 
199 	return ret;
200 }
201 
202 static int addr4_resolve(struct sockaddr_in *src_in,
203 			 struct sockaddr_in *dst_in,
204 			 struct rdma_dev_addr *addr)
205 {
206 	__be32 src_ip = src_in->sin_addr.s_addr;
207 	__be32 dst_ip = dst_in->sin_addr.s_addr;
208 	struct rtable *rt;
209 	struct flowi4 fl4;
210 	int ret;
211 
212 	memset(&fl4, 0, sizeof(fl4));
213 	fl4.daddr = dst_ip;
214 	fl4.saddr = src_ip;
215 	fl4.flowi4_oif = addr->bound_dev_if;
216 	rt = ip_route_output_key(&init_net, &fl4);
217 	if (IS_ERR(rt)) {
218 		ret = PTR_ERR(rt);
219 		goto out;
220 	}
221 	src_in->sin_family = AF_INET;
222 	src_in->sin_addr.s_addr = fl4.saddr;
223 
224 	if (rt->dst.dev->flags & IFF_LOOPBACK) {
225 		ret = rdma_translate_ip((struct sockaddr *) dst_in, addr);
226 		if (!ret)
227 			memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
228 		goto put;
229 	}
230 
231 	/* If the device does ARP internally, return 'done' */
232 	if (rt->dst.dev->flags & IFF_NOARP) {
233 		ret = rdma_copy_addr(addr, rt->dst.dev, NULL);
234 		goto put;
235 	}
236 
237 	ret = dst_fetch_ha(&rt->dst, addr, &fl4.daddr);
238 put:
239 	ip_rt_put(rt);
240 out:
241 	return ret;
242 }
243 
244 #if IS_ENABLED(CONFIG_IPV6)
245 static int addr6_resolve(struct sockaddr_in6 *src_in,
246 			 struct sockaddr_in6 *dst_in,
247 			 struct rdma_dev_addr *addr)
248 {
249 	struct flowi6 fl6;
250 	struct dst_entry *dst;
251 	int ret;
252 
253 	memset(&fl6, 0, sizeof fl6);
254 	fl6.daddr = dst_in->sin6_addr;
255 	fl6.saddr = src_in->sin6_addr;
256 	fl6.flowi6_oif = addr->bound_dev_if;
257 
258 	dst = ip6_route_output(&init_net, NULL, &fl6);
259 	if ((ret = dst->error))
260 		goto put;
261 
262 	if (ipv6_addr_any(&fl6.saddr)) {
263 		ret = ipv6_dev_get_saddr(&init_net, ip6_dst_idev(dst)->dev,
264 					 &fl6.daddr, 0, &fl6.saddr);
265 		if (ret)
266 			goto put;
267 
268 		src_in->sin6_family = AF_INET6;
269 		src_in->sin6_addr = fl6.saddr;
270 	}
271 
272 	if (dst->dev->flags & IFF_LOOPBACK) {
273 		ret = rdma_translate_ip((struct sockaddr *) dst_in, addr);
274 		if (!ret)
275 			memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
276 		goto put;
277 	}
278 
279 	/* If the device does ARP internally, return 'done' */
280 	if (dst->dev->flags & IFF_NOARP) {
281 		ret = rdma_copy_addr(addr, dst->dev, NULL);
282 		goto put;
283 	}
284 
285 	ret = dst_fetch_ha(dst, addr, &fl6.daddr);
286 put:
287 	dst_release(dst);
288 	return ret;
289 }
290 #else
291 static int addr6_resolve(struct sockaddr_in6 *src_in,
292 			 struct sockaddr_in6 *dst_in,
293 			 struct rdma_dev_addr *addr)
294 {
295 	return -EADDRNOTAVAIL;
296 }
297 #endif
298 
299 static int addr_resolve(struct sockaddr *src_in,
300 			struct sockaddr *dst_in,
301 			struct rdma_dev_addr *addr)
302 {
303 	if (src_in->sa_family == AF_INET) {
304 		return addr4_resolve((struct sockaddr_in *) src_in,
305 			(struct sockaddr_in *) dst_in, addr);
306 	} else
307 		return addr6_resolve((struct sockaddr_in6 *) src_in,
308 			(struct sockaddr_in6 *) dst_in, addr);
309 }
310 
311 static void process_req(struct work_struct *work)
312 {
313 	struct addr_req *req, *temp_req;
314 	struct sockaddr *src_in, *dst_in;
315 	struct list_head done_list;
316 
317 	INIT_LIST_HEAD(&done_list);
318 
319 	mutex_lock(&lock);
320 	list_for_each_entry_safe(req, temp_req, &req_list, list) {
321 		if (req->status == -ENODATA) {
322 			src_in = (struct sockaddr *) &req->src_addr;
323 			dst_in = (struct sockaddr *) &req->dst_addr;
324 			req->status = addr_resolve(src_in, dst_in, req->addr);
325 			if (req->status && time_after_eq(jiffies, req->timeout))
326 				req->status = -ETIMEDOUT;
327 			else if (req->status == -ENODATA)
328 				continue;
329 		}
330 		list_move_tail(&req->list, &done_list);
331 	}
332 
333 	if (!list_empty(&req_list)) {
334 		req = list_entry(req_list.next, struct addr_req, list);
335 		set_timeout(req->timeout);
336 	}
337 	mutex_unlock(&lock);
338 
339 	list_for_each_entry_safe(req, temp_req, &done_list, list) {
340 		list_del(&req->list);
341 		req->callback(req->status, (struct sockaddr *) &req->src_addr,
342 			req->addr, req->context);
343 		put_client(req->client);
344 		kfree(req);
345 	}
346 }
347 
348 int rdma_resolve_ip(struct rdma_addr_client *client,
349 		    struct sockaddr *src_addr, struct sockaddr *dst_addr,
350 		    struct rdma_dev_addr *addr, int timeout_ms,
351 		    void (*callback)(int status, struct sockaddr *src_addr,
352 				     struct rdma_dev_addr *addr, void *context),
353 		    void *context)
354 {
355 	struct sockaddr *src_in, *dst_in;
356 	struct addr_req *req;
357 	int ret = 0;
358 
359 	req = kzalloc(sizeof *req, GFP_KERNEL);
360 	if (!req)
361 		return -ENOMEM;
362 
363 	src_in = (struct sockaddr *) &req->src_addr;
364 	dst_in = (struct sockaddr *) &req->dst_addr;
365 
366 	if (src_addr) {
367 		if (src_addr->sa_family != dst_addr->sa_family) {
368 			ret = -EINVAL;
369 			goto err;
370 		}
371 
372 		memcpy(src_in, src_addr, ip_addr_size(src_addr));
373 	} else {
374 		src_in->sa_family = dst_addr->sa_family;
375 	}
376 
377 	memcpy(dst_in, dst_addr, ip_addr_size(dst_addr));
378 	req->addr = addr;
379 	req->callback = callback;
380 	req->context = context;
381 	req->client = client;
382 	atomic_inc(&client->refcount);
383 
384 	req->status = addr_resolve(src_in, dst_in, addr);
385 	switch (req->status) {
386 	case 0:
387 		req->timeout = jiffies;
388 		queue_req(req);
389 		break;
390 	case -ENODATA:
391 		req->timeout = msecs_to_jiffies(timeout_ms) + jiffies;
392 		queue_req(req);
393 		break;
394 	default:
395 		ret = req->status;
396 		atomic_dec(&client->refcount);
397 		goto err;
398 	}
399 	return ret;
400 err:
401 	kfree(req);
402 	return ret;
403 }
404 EXPORT_SYMBOL(rdma_resolve_ip);
405 
406 void rdma_addr_cancel(struct rdma_dev_addr *addr)
407 {
408 	struct addr_req *req, *temp_req;
409 
410 	mutex_lock(&lock);
411 	list_for_each_entry_safe(req, temp_req, &req_list, list) {
412 		if (req->addr == addr) {
413 			req->status = -ECANCELED;
414 			req->timeout = jiffies;
415 			list_move(&req->list, &req_list);
416 			set_timeout(req->timeout);
417 			break;
418 		}
419 	}
420 	mutex_unlock(&lock);
421 }
422 EXPORT_SYMBOL(rdma_addr_cancel);
423 
424 static int netevent_callback(struct notifier_block *self, unsigned long event,
425 	void *ctx)
426 {
427 	if (event == NETEVENT_NEIGH_UPDATE) {
428 		struct neighbour *neigh = ctx;
429 
430 		if (neigh->nud_state & NUD_VALID) {
431 			set_timeout(jiffies);
432 		}
433 	}
434 	return 0;
435 }
436 
437 static struct notifier_block nb = {
438 	.notifier_call = netevent_callback
439 };
440 
441 static int __init addr_init(void)
442 {
443 	addr_wq = create_singlethread_workqueue("ib_addr");
444 	if (!addr_wq)
445 		return -ENOMEM;
446 
447 	register_netevent_notifier(&nb);
448 	return 0;
449 }
450 
451 static void __exit addr_cleanup(void)
452 {
453 	unregister_netevent_notifier(&nb);
454 	destroy_workqueue(addr_wq);
455 }
456 
457 module_init(addr_init);
458 module_exit(addr_cleanup);
459