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 <linux/notifier.h>
42#include <net/route.h>
43#include <net/netevent.h>
44#include <rdma/ib_addr.h>
45#include <netinet/if_ether.h>
46#include <netinet6/scope6_var.h>
47
48
49MODULE_AUTHOR("Sean Hefty");
50MODULE_DESCRIPTION("IB Address Translation");
51MODULE_LICENSE("Dual BSD/GPL");
52
53struct 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
66static void process_req(struct work_struct *work);
67
68static DEFINE_MUTEX(lock);
69static LIST_HEAD(req_list);
70static struct delayed_work work;
71static struct workqueue_struct *addr_wq;
72
73static struct rdma_addr_client self;
74void rdma_addr_register_client(struct rdma_addr_client *client)
75{
76	atomic_set(&client->refcount, 1);
77	init_completion(&client->comp);
78}
79EXPORT_SYMBOL(rdma_addr_register_client);
80
81static inline void put_client(struct rdma_addr_client *client)
82{
83	if (atomic_dec_and_test(&client->refcount))
84		complete(&client->comp);
85}
86
87void rdma_addr_unregister_client(struct rdma_addr_client *client)
88{
89	put_client(client);
90	wait_for_completion(&client->comp);
91}
92EXPORT_SYMBOL(rdma_addr_unregister_client);
93
94int rdma_copy_addr(struct rdma_dev_addr *dev_addr, struct ifnet *dev,
95		     const unsigned char *dst_dev_addr)
96{
97	if (dev->if_type == IFT_INFINIBAND)
98		dev_addr->dev_type = ARPHRD_INFINIBAND;
99	else if (dev->if_type == IFT_ETHER)
100		dev_addr->dev_type = ARPHRD_ETHER;
101	else
102		dev_addr->dev_type = 0;
103	memcpy(dev_addr->src_dev_addr, IF_LLADDR(dev), dev->if_addrlen);
104	memcpy(dev_addr->broadcast, __DECONST(char *, dev->if_broadcastaddr),
105	    dev->if_addrlen);
106	if (dst_dev_addr)
107		memcpy(dev_addr->dst_dev_addr, dst_dev_addr, dev->if_addrlen);
108	dev_addr->bound_dev_if = dev->if_index;
109	return 0;
110}
111EXPORT_SYMBOL(rdma_copy_addr);
112
113#define	SCOPE_ID_CACHE(_scope_id, _addr6) do {		\
114	(_addr6)->sin6_addr.s6_addr[3] = (_scope_id);	\
115	(_addr6)->sin6_scope_id = 0; } while (0)
116
117#define	SCOPE_ID_RESTORE(_scope_id, _addr6) do {	\
118	(_addr6)->sin6_scope_id = (_scope_id);		\
119	(_addr6)->sin6_addr.s6_addr[3] = 0; } while (0)
120
121int rdma_translate_ip(struct sockaddr *addr, struct rdma_dev_addr *dev_addr,
122		      u16 *vlan_id)
123{
124	struct net_device *dev;
125	int ret = -EADDRNOTAVAIL;
126
127	if (dev_addr->bound_dev_if) {
128		dev = dev_get_by_index(&init_net, dev_addr->bound_dev_if);
129		if (!dev)
130			return -ENODEV;
131		ret = rdma_copy_addr(dev_addr, dev, NULL);
132		dev_put(dev);
133		return ret;
134	}
135
136	switch (addr->sa_family) {
137	case AF_INET:
138		dev = ip_dev_find(&init_net,
139			((struct sockaddr_in *) addr)->sin_addr.s_addr);
140
141		if (!dev)
142			return ret;
143
144		ret = rdma_copy_addr(dev_addr, dev, NULL);
145		if (vlan_id)
146			*vlan_id = rdma_vlan_dev_vlan_id(dev);
147		dev_put(dev);
148		break;
149
150#if defined(INET6)
151	case AF_INET6:
152		{
153			struct sockaddr_in6 *sin6;
154			struct ifaddr *ifa;
155			in_port_t port;
156			uint32_t scope_id;
157
158			sin6 = (struct sockaddr_in6 *)addr;
159			port = sin6->sin6_port;
160			sin6->sin6_port = 0;
161			scope_id = sin6->sin6_scope_id;
162			if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr))
163				SCOPE_ID_CACHE(scope_id, sin6);
164			ifa = ifa_ifwithaddr(addr);
165			sin6->sin6_port = port;
166			if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr))
167				SCOPE_ID_RESTORE(scope_id, sin6);
168			if (ifa == NULL) {
169				ret = -ENODEV;
170				break;
171			}
172			ret = rdma_copy_addr(dev_addr, ifa->ifa_ifp, NULL);
173			if (vlan_id)
174				*vlan_id = rdma_vlan_dev_vlan_id(ifa->ifa_ifp);
175			ifa_free(ifa);
176			break;
177		}
178#endif
179	default:
180		break;
181	}
182	return ret;
183}
184EXPORT_SYMBOL(rdma_translate_ip);
185
186static void set_timeout(unsigned long time)
187{
188	unsigned long delay;
189
190	delay = time - jiffies;
191	if ((long)delay <= 0)
192		delay = 1;
193
194	mod_delayed_work(addr_wq, &work, delay);
195}
196
197static void queue_req(struct addr_req *req)
198{
199	struct addr_req *temp_req;
200
201	mutex_lock(&lock);
202	list_for_each_entry_reverse(temp_req, &req_list, list) {
203		if (time_after_eq(req->timeout, temp_req->timeout))
204			break;
205	}
206
207	list_add(&req->list, &temp_req->list);
208
209	if (req_list.next == &req->list)
210		set_timeout(req->timeout);
211	mutex_unlock(&lock);
212}
213
214static int addr_resolve(struct sockaddr *src_in,
215			struct sockaddr *dst_in,
216			struct rdma_dev_addr *addr)
217{
218	struct sockaddr_in *sin;
219	struct sockaddr_in6 *sin6;
220	struct ifaddr *ifa;
221	struct ifnet *ifp;
222	struct rtentry *rte;
223#if defined(INET) || defined(INET6)
224	in_port_t port;
225#endif
226#ifdef INET6
227	uint32_t scope_id;
228#endif
229	u_char edst[MAX_ADDR_LEN];
230	int multi;
231	int bcast;
232	int is_gw = 0;
233	int error = 0;
234	/*
235	 * Determine whether the address is unicast, multicast, or broadcast
236	 * and whether the source interface is valid.
237	 */
238	multi = 0;
239	bcast = 0;
240	sin = NULL;
241	sin6 = NULL;
242	ifp = NULL;
243	rte = NULL;
244	ifa = NULL;
245	ifp = NULL;
246	memset(edst, 0, sizeof(edst));
247#ifdef INET6
248	scope_id = -1U;
249#endif
250
251	switch (dst_in->sa_family) {
252#ifdef INET
253	case AF_INET:
254		sin = (struct sockaddr_in *)dst_in;
255		if (sin->sin_addr.s_addr == INADDR_BROADCAST)
256			bcast = 1;
257		if (IN_MULTICAST(ntohl(sin->sin_addr.s_addr)))
258			multi = 1;
259		sin = (struct sockaddr_in *)src_in;
260		if (sin->sin_addr.s_addr != INADDR_ANY) {
261			/*
262			 * Address comparison fails if the port is set
263			 * cache it here to be restored later.
264			 */
265			port = sin->sin_port;
266			sin->sin_port = 0;
267			memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
268
269			/*
270			 * If we have a source address to use look it
271			 * up first and verify that it is a local
272			 * interface:
273			 */
274			ifa = ifa_ifwithaddr(src_in);
275			sin->sin_port = port;
276			if (ifa == NULL) {
277				error = ENETUNREACH;
278				goto done;
279			}
280			ifp = ifa->ifa_ifp;
281			ifa_free(ifa);
282			if (bcast || multi)
283				goto mcast;
284		}
285		break;
286#endif
287#ifdef INET6
288	case AF_INET6:
289		sin6 = (struct sockaddr_in6 *)dst_in;
290		if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
291			multi = 1;
292		if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr)) {
293			/*
294			 * The IB address comparison fails if the
295			 * scope ID is set and not part of the addr:
296			 */
297			scope_id = sin6->sin6_scope_id;
298			if (scope_id < 256)
299				SCOPE_ID_CACHE(scope_id, sin6);
300		}
301		sin6 = (struct sockaddr_in6 *)src_in;
302		if (!IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
303			port = sin6->sin6_port;
304			sin6->sin6_port = 0;
305			if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr)) {
306				if (scope_id < 256)
307					SCOPE_ID_CACHE(scope_id, sin6);
308			}
309
310			/*
311			 * If we have a source address to use look it
312			 * up first and verify that it is a local
313			 * interface:
314			 */
315			ifa = ifa_ifwithaddr(src_in);
316			sin6->sin6_port = port;
317			if (ifa == NULL) {
318				error = ENETUNREACH;
319				goto done;
320			}
321			ifp = ifa->ifa_ifp;
322			ifa_free(ifa);
323			if (bcast || multi)
324				goto mcast;
325		}
326		break;
327#endif
328	default:
329		error = EINVAL;
330		goto done;
331	}
332	/*
333	 * Make sure the route exists and has a valid link.
334	 */
335	rte = rtalloc1(dst_in, 1, 0);
336	if (rte == NULL || rte->rt_ifp == NULL || !RT_LINK_IS_UP(rte->rt_ifp)) {
337		if (rte)
338			RTFREE_LOCKED(rte);
339		error = EHOSTUNREACH;
340		goto done;
341	}
342	if (rte->rt_flags & RTF_GATEWAY)
343		is_gw = 1;
344	/*
345	 * If it's not multicast or broadcast and the route doesn't match the
346	 * requested interface return unreachable.  Otherwise fetch the
347	 * correct interface pointer and unlock the route.
348	 */
349	if (multi || bcast) {
350		if (ifp == NULL) {
351			ifp = rte->rt_ifp;
352			/* rt_ifa holds the route answer source address */
353			ifa = rte->rt_ifa;
354		}
355		RTFREE_LOCKED(rte);
356	} else if (ifp && ifp != rte->rt_ifp) {
357		RTFREE_LOCKED(rte);
358		error = ENETUNREACH;
359		goto done;
360	} else {
361		if (ifp == NULL) {
362			ifp = rte->rt_ifp;
363			ifa = rte->rt_ifa;
364		}
365		RT_UNLOCK(rte);
366	}
367#if defined(INET) || defined(INET6)
368mcast:
369#endif
370	if (bcast) {
371		memcpy(edst, ifp->if_broadcastaddr, ifp->if_addrlen);
372		goto done;
373	} else if (multi) {
374		struct sockaddr *llsa;
375		struct sockaddr_dl sdl;
376
377		sdl.sdl_len = sizeof(sdl);
378		llsa = (struct sockaddr *)&sdl;
379
380		if (ifp->if_resolvemulti == NULL) {
381			error = EOPNOTSUPP;
382			goto done;
383		}
384		error = ifp->if_resolvemulti(ifp, &llsa, dst_in);
385		if (error == 0) {
386			memcpy(edst, LLADDR((struct sockaddr_dl *)llsa),
387			    ifp->if_addrlen);
388		}
389		goto done;
390	}
391	/*
392	 * Resolve the link local address.
393	 */
394	switch (dst_in->sa_family) {
395#ifdef INET
396	case AF_INET:
397		error = arpresolve(ifp, is_gw, NULL,
398		    is_gw ? rte->rt_gateway : dst_in, edst, NULL, NULL);
399		break;
400#endif
401#ifdef INET6
402	case AF_INET6:
403		error = nd6_resolve(ifp, is_gw, NULL,
404		    is_gw ? rte->rt_gateway : dst_in, edst, NULL, NULL);
405		break;
406#endif
407	default:
408		KASSERT(0, ("rdma_addr_resolve: Unreachable"));
409		error = EINVAL;
410		break;
411	}
412	RTFREE(rte);
413done:
414	if (error == 0)
415		error = -rdma_copy_addr(addr, ifp, edst);
416	if (error == 0)
417		memcpy(src_in, ifa->ifa_addr, ip_addr_size(ifa->ifa_addr));
418#ifdef INET6
419	if (scope_id < 256) {
420		sin6 = (struct sockaddr_in6 *)src_in;
421		if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr))
422			SCOPE_ID_RESTORE(scope_id, sin6);
423		sin6 = (struct sockaddr_in6 *)dst_in;
424		SCOPE_ID_RESTORE(scope_id, sin6);
425	}
426#endif
427	if (error == EWOULDBLOCK)
428		error = ENODATA;
429	return -error;
430}
431
432static void process_req(struct work_struct *work)
433{
434	struct addr_req *req, *temp_req;
435	struct sockaddr *src_in, *dst_in;
436	struct list_head done_list;
437
438	INIT_LIST_HEAD(&done_list);
439
440	mutex_lock(&lock);
441	list_for_each_entry_safe(req, temp_req, &req_list, list) {
442		if (req->status == -ENODATA) {
443			src_in = (struct sockaddr *) &req->src_addr;
444			dst_in = (struct sockaddr *) &req->dst_addr;
445			req->status = addr_resolve(src_in, dst_in, req->addr);
446			if (req->status && time_after_eq(jiffies, req->timeout))
447				req->status = -ETIMEDOUT;
448			else if (req->status == -ENODATA)
449				continue;
450		}
451		list_move_tail(&req->list, &done_list);
452	}
453
454	if (!list_empty(&req_list)) {
455		req = list_entry(req_list.next, struct addr_req, list);
456		set_timeout(req->timeout);
457	}
458	mutex_unlock(&lock);
459
460	list_for_each_entry_safe(req, temp_req, &done_list, list) {
461		list_del(&req->list);
462		req->callback(req->status, (struct sockaddr *) &req->src_addr,
463			req->addr, req->context);
464		put_client(req->client);
465		kfree(req);
466	}
467}
468
469int rdma_resolve_ip(struct rdma_addr_client *client,
470		    struct sockaddr *src_addr, struct sockaddr *dst_addr,
471		    struct rdma_dev_addr *addr, int timeout_ms,
472		    void (*callback)(int status, struct sockaddr *src_addr,
473				     struct rdma_dev_addr *addr, void *context),
474		    void *context)
475{
476	struct sockaddr *src_in, *dst_in;
477	struct addr_req *req;
478	int ret = 0;
479
480	req = kzalloc(sizeof *req, GFP_KERNEL);
481	if (!req)
482		return -ENOMEM;
483
484	src_in = (struct sockaddr *) &req->src_addr;
485	dst_in = (struct sockaddr *) &req->dst_addr;
486
487	if (src_addr) {
488		if (src_addr->sa_family != dst_addr->sa_family) {
489			ret = -EINVAL;
490			goto err;
491		}
492
493		memcpy(src_in, src_addr, ip_addr_size(src_addr));
494	} else {
495		src_in->sa_family = dst_addr->sa_family;
496	}
497
498	memcpy(dst_in, dst_addr, ip_addr_size(dst_addr));
499	req->addr = addr;
500	req->callback = callback;
501	req->context = context;
502	req->client = client;
503	atomic_inc(&client->refcount);
504
505	req->status = addr_resolve(src_in, dst_in, addr);
506	switch (req->status) {
507	case 0:
508		req->timeout = jiffies;
509		queue_req(req);
510		break;
511	case -ENODATA:
512		req->timeout = msecs_to_jiffies(timeout_ms) + jiffies;
513		queue_req(req);
514		break;
515	default:
516		ret = req->status;
517		atomic_dec(&client->refcount);
518		goto err;
519	}
520	return ret;
521err:
522	kfree(req);
523	return ret;
524}
525EXPORT_SYMBOL(rdma_resolve_ip);
526
527void rdma_addr_cancel(struct rdma_dev_addr *addr)
528{
529	struct addr_req *req, *temp_req;
530
531	mutex_lock(&lock);
532	list_for_each_entry_safe(req, temp_req, &req_list, list) {
533		if (req->addr == addr) {
534			req->status = -ECANCELED;
535			req->timeout = jiffies;
536			list_move(&req->list, &req_list);
537			set_timeout(req->timeout);
538			break;
539		}
540	}
541	mutex_unlock(&lock);
542}
543EXPORT_SYMBOL(rdma_addr_cancel);
544
545struct resolve_cb_context {
546	struct rdma_dev_addr *addr;
547	struct completion comp;
548};
549
550static void resolve_cb(int status, struct sockaddr *src_addr,
551	     struct rdma_dev_addr *addr, void *context)
552{
553	memcpy(((struct resolve_cb_context *)context)->addr, addr, sizeof(struct
554				rdma_dev_addr));
555	complete(&((struct resolve_cb_context *)context)->comp);
556}
557
558int rdma_addr_find_dmac_by_grh(union ib_gid *sgid, union ib_gid *dgid, u8 *dmac,
559			       u16 *vlan_id, u32 scope_id)
560{
561	int ret = 0;
562	struct rdma_dev_addr dev_addr;
563	struct resolve_cb_context ctx;
564	struct net_device *dev;
565
566	union {
567		struct sockaddr     _sockaddr;
568		struct sockaddr_in  _sockaddr_in;
569		struct sockaddr_in6 _sockaddr_in6;
570	} sgid_addr, dgid_addr;
571
572
573	ret = rdma_gid2ip(&sgid_addr._sockaddr, sgid, scope_id);
574	if (ret)
575		return ret;
576
577	ret = rdma_gid2ip(&dgid_addr._sockaddr, dgid, scope_id);
578	if (ret)
579		return ret;
580
581	memset(&dev_addr, 0, sizeof(dev_addr));
582
583	ctx.addr = &dev_addr;
584	init_completion(&ctx.comp);
585	ret = rdma_resolve_ip(&self, &sgid_addr._sockaddr, &dgid_addr._sockaddr,
586			&dev_addr, 1000, resolve_cb, &ctx);
587	if (ret)
588		return ret;
589
590	wait_for_completion(&ctx.comp);
591
592	memcpy(dmac, dev_addr.dst_dev_addr, ETH_ALEN);
593	dev = dev_get_by_index(&init_net, dev_addr.bound_dev_if);
594	if (!dev)
595		return -ENODEV;
596	if (vlan_id)
597		*vlan_id = rdma_vlan_dev_vlan_id(dev);
598	dev_put(dev);
599	return ret;
600}
601EXPORT_SYMBOL(rdma_addr_find_dmac_by_grh);
602
603u32 rdma_get_ipv6_scope_id(struct ib_device *ib, u8 port_num)
604{
605#ifdef INET6
606	struct ifnet *ifp;
607	if (ib->get_netdev == NULL)
608		return (-1U);
609	ifp = ib->get_netdev(ib, port_num);
610	if (ifp == NULL)
611		return (-1U);
612	return (in6_getscopezone(ifp, IPV6_ADDR_SCOPE_LINKLOCAL));
613#else
614	return (-1U);
615#endif
616}
617
618int rdma_addr_find_smac_by_sgid(union ib_gid *sgid, u8 *smac, u16 *vlan_id,
619    u32 scope_id)
620{
621	int ret = 0;
622	struct rdma_dev_addr dev_addr;
623	union {
624		struct sockaddr     _sockaddr;
625		struct sockaddr_in  _sockaddr_in;
626		struct sockaddr_in6 _sockaddr_in6;
627	} gid_addr;
628
629	ret = rdma_gid2ip(&gid_addr._sockaddr, sgid, scope_id);
630	if (ret)
631		return ret;
632	memset(&dev_addr, 0, sizeof(dev_addr));
633	ret = rdma_translate_ip(&gid_addr._sockaddr, &dev_addr, vlan_id);
634	if (ret)
635		return ret;
636
637	memcpy(smac, dev_addr.src_dev_addr, ETH_ALEN);
638	return ret;
639}
640EXPORT_SYMBOL(rdma_addr_find_smac_by_sgid);
641
642static int netevent_callback(struct notifier_block *self, unsigned long event,
643	void *ctx)
644{
645	if (event == NETEVENT_NEIGH_UPDATE) {
646			set_timeout(jiffies);
647		}
648	return 0;
649}
650
651static struct notifier_block nb = {
652	.notifier_call = netevent_callback
653};
654
655static int __init addr_init(void)
656{
657	INIT_DELAYED_WORK(&work, process_req);
658	addr_wq = create_singlethread_workqueue("ib_addr");
659	if (!addr_wq)
660		return -ENOMEM;
661
662	register_netevent_notifier(&nb);
663	rdma_addr_register_client(&self);
664	return 0;
665}
666
667static void __exit addr_cleanup(void)
668{
669	rdma_addr_unregister_client(&self);
670	unregister_netevent_notifier(&nb);
671	destroy_workqueue(addr_wq);
672}
673
674module_init(addr_init);
675module_exit(addr_cleanup);
676