1 /*
2  * Copyright (c) 2014 Chelsio, Inc. All rights reserved.
3  * Copyright (c) 2014 Intel Corporation. All rights reserved.
4  *
5  * This software is available to you under a choice of one of two
6  * licenses.  You may choose to be licensed under the terms of the GNU
7  * General Public License (GPL) Version 2, available from the file
8  * COPYING in the main directory of this source tree, or the
9  * OpenIB.org BSD license below:
10  *
11  *     Redistribution and use in source and binary forms, with or
12  *     without modification, are permitted provided that the following
13  *     conditions are met:
14  *
15  *      - Redistributions of source code must retain the above
16  *	  copyright notice, this list of conditions and the following
17  *	  disclaimer.
18  *
19  *      - Redistributions in binary form must reproduce the above
20  *	  copyright notice, this list of conditions and the following
21  *	  disclaimer in the documentation and/or other materials
22  *	  provided with the distribution.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31  * SOFTWARE.
32  */
33 
34 #include "iwpm_util.h"
35 
36 #define IWPM_MAPINFO_HASH_SIZE	512
37 #define IWPM_MAPINFO_HASH_MASK	(IWPM_MAPINFO_HASH_SIZE - 1)
38 #define IWPM_REMINFO_HASH_SIZE	64
39 #define IWPM_REMINFO_HASH_MASK	(IWPM_REMINFO_HASH_SIZE - 1)
40 #define IWPM_MSG_SIZE		512
41 
42 static LIST_HEAD(iwpm_nlmsg_req_list);
43 static DEFINE_SPINLOCK(iwpm_nlmsg_req_lock);
44 
45 static struct hlist_head *iwpm_hash_bucket;
46 static DEFINE_SPINLOCK(iwpm_mapinfo_lock);
47 
48 static struct hlist_head *iwpm_reminfo_bucket;
49 static DEFINE_SPINLOCK(iwpm_reminfo_lock);
50 
51 static DEFINE_MUTEX(iwpm_admin_lock);
52 static struct iwpm_admin_data iwpm_admin;
53 
54 /**
55  * iwpm_init - Allocate resources for the iwarp port mapper
56  * @nl_client: The index of the netlink client
57  *
58  * Should be called when network interface goes up.
59  */
60 int iwpm_init(u8 nl_client)
61 {
62 	int ret = 0;
63 	mutex_lock(&iwpm_admin_lock);
64 	if (!refcount_read(&iwpm_admin.refcount)) {
65 		iwpm_hash_bucket = kcalloc(IWPM_MAPINFO_HASH_SIZE,
66 					   sizeof(struct hlist_head),
67 					   GFP_KERNEL);
68 		if (!iwpm_hash_bucket) {
69 			ret = -ENOMEM;
70 			goto init_exit;
71 		}
72 		iwpm_reminfo_bucket = kcalloc(IWPM_REMINFO_HASH_SIZE,
73 					      sizeof(struct hlist_head),
74 					      GFP_KERNEL);
75 		if (!iwpm_reminfo_bucket) {
76 			kfree(iwpm_hash_bucket);
77 			ret = -ENOMEM;
78 			goto init_exit;
79 		}
80 
81 		refcount_set(&iwpm_admin.refcount, 1);
82 	} else {
83 		refcount_inc(&iwpm_admin.refcount);
84 	}
85 
86 init_exit:
87 	mutex_unlock(&iwpm_admin_lock);
88 	if (!ret) {
89 		iwpm_set_valid(nl_client, 1);
90 		iwpm_set_registration(nl_client, IWPM_REG_UNDEF);
91 		pr_debug("%s: Mapinfo and reminfo tables are created\n",
92 				__func__);
93 	}
94 	return ret;
95 }
96 
97 static void free_hash_bucket(void);
98 static void free_reminfo_bucket(void);
99 
100 /**
101  * iwpm_exit - Deallocate resources for the iwarp port mapper
102  * @nl_client: The index of the netlink client
103  *
104  * Should be called when network interface goes down.
105  */
106 int iwpm_exit(u8 nl_client)
107 {
108 
109 	if (!iwpm_valid_client(nl_client))
110 		return -EINVAL;
111 	mutex_lock(&iwpm_admin_lock);
112 	if (!refcount_read(&iwpm_admin.refcount)) {
113 		mutex_unlock(&iwpm_admin_lock);
114 		pr_err("%s Incorrect usage - negative refcount\n", __func__);
115 		return -EINVAL;
116 	}
117 	if (refcount_dec_and_test(&iwpm_admin.refcount)) {
118 		free_hash_bucket();
119 		free_reminfo_bucket();
120 		pr_debug("%s: Resources are destroyed\n", __func__);
121 	}
122 	mutex_unlock(&iwpm_admin_lock);
123 	iwpm_set_valid(nl_client, 0);
124 	iwpm_set_registration(nl_client, IWPM_REG_UNDEF);
125 	return 0;
126 }
127 
128 static struct hlist_head *get_mapinfo_hash_bucket(struct sockaddr_storage *,
129 					       struct sockaddr_storage *);
130 
131 /**
132  * iwpm_create_mapinfo - Store local and mapped IPv4/IPv6 address
133  *                       info in a hash table
134  * @local_sockaddr: Local ip/tcp address
135  * @mapped_sockaddr: Mapped local ip/tcp address
136  * @nl_client: The index of the netlink client
137  * @map_flags: IWPM mapping flags
138  */
139 int iwpm_create_mapinfo(struct sockaddr_storage *local_sockaddr,
140 			struct sockaddr_storage *mapped_sockaddr,
141 			u8 nl_client, u32 map_flags)
142 {
143 	struct hlist_head *hash_bucket_head = NULL;
144 	struct iwpm_mapping_info *map_info;
145 	unsigned long flags;
146 	int ret = -EINVAL;
147 
148 	if (!iwpm_valid_client(nl_client))
149 		return ret;
150 	map_info = kzalloc(sizeof(struct iwpm_mapping_info), GFP_KERNEL);
151 	if (!map_info)
152 		return -ENOMEM;
153 
154 	memcpy(&map_info->local_sockaddr, local_sockaddr,
155 	       sizeof(struct sockaddr_storage));
156 	memcpy(&map_info->mapped_sockaddr, mapped_sockaddr,
157 	       sizeof(struct sockaddr_storage));
158 	map_info->nl_client = nl_client;
159 	map_info->map_flags = map_flags;
160 
161 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
162 	if (iwpm_hash_bucket) {
163 		hash_bucket_head = get_mapinfo_hash_bucket(
164 					&map_info->local_sockaddr,
165 					&map_info->mapped_sockaddr);
166 		if (hash_bucket_head) {
167 			hlist_add_head(&map_info->hlist_node, hash_bucket_head);
168 			ret = 0;
169 		}
170 	}
171 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
172 
173 	if (!hash_bucket_head)
174 		kfree(map_info);
175 	return ret;
176 }
177 
178 /**
179  * iwpm_remove_mapinfo - Remove local and mapped IPv4/IPv6 address
180  *                       info from the hash table
181  * @local_sockaddr: Local ip/tcp address
182  * @mapped_local_addr: Mapped local ip/tcp address
183  *
184  * Returns err code if mapping info is not found in the hash table,
185  * otherwise returns 0
186  */
187 int iwpm_remove_mapinfo(struct sockaddr_storage *local_sockaddr,
188 			struct sockaddr_storage *mapped_local_addr)
189 {
190 	struct hlist_node *tmp_hlist_node;
191 	struct hlist_head *hash_bucket_head;
192 	struct iwpm_mapping_info *map_info = NULL;
193 	unsigned long flags;
194 	int ret = -EINVAL;
195 
196 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
197 	if (iwpm_hash_bucket) {
198 		hash_bucket_head = get_mapinfo_hash_bucket(
199 					local_sockaddr,
200 					mapped_local_addr);
201 		if (!hash_bucket_head)
202 			goto remove_mapinfo_exit;
203 
204 		hlist_for_each_entry_safe(map_info, tmp_hlist_node,
205 					hash_bucket_head, hlist_node) {
206 
207 			if (!iwpm_compare_sockaddr(&map_info->mapped_sockaddr,
208 						mapped_local_addr)) {
209 
210 				hlist_del_init(&map_info->hlist_node);
211 				kfree(map_info);
212 				ret = 0;
213 				break;
214 			}
215 		}
216 	}
217 remove_mapinfo_exit:
218 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
219 	return ret;
220 }
221 
222 static void free_hash_bucket(void)
223 {
224 	struct hlist_node *tmp_hlist_node;
225 	struct iwpm_mapping_info *map_info;
226 	unsigned long flags;
227 	int i;
228 
229 	/* remove all the mapinfo data from the list */
230 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
231 	for (i = 0; i < IWPM_MAPINFO_HASH_SIZE; i++) {
232 		hlist_for_each_entry_safe(map_info, tmp_hlist_node,
233 			&iwpm_hash_bucket[i], hlist_node) {
234 
235 				hlist_del_init(&map_info->hlist_node);
236 				kfree(map_info);
237 			}
238 	}
239 	/* free the hash list */
240 	kfree(iwpm_hash_bucket);
241 	iwpm_hash_bucket = NULL;
242 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
243 }
244 
245 static void free_reminfo_bucket(void)
246 {
247 	struct hlist_node *tmp_hlist_node;
248 	struct iwpm_remote_info *rem_info;
249 	unsigned long flags;
250 	int i;
251 
252 	/* remove all the remote info from the list */
253 	spin_lock_irqsave(&iwpm_reminfo_lock, flags);
254 	for (i = 0; i < IWPM_REMINFO_HASH_SIZE; i++) {
255 		hlist_for_each_entry_safe(rem_info, tmp_hlist_node,
256 			&iwpm_reminfo_bucket[i], hlist_node) {
257 
258 				hlist_del_init(&rem_info->hlist_node);
259 				kfree(rem_info);
260 			}
261 	}
262 	/* free the hash list */
263 	kfree(iwpm_reminfo_bucket);
264 	iwpm_reminfo_bucket = NULL;
265 	spin_unlock_irqrestore(&iwpm_reminfo_lock, flags);
266 }
267 
268 static struct hlist_head *get_reminfo_hash_bucket(struct sockaddr_storage *,
269 						struct sockaddr_storage *);
270 
271 void iwpm_add_remote_info(struct iwpm_remote_info *rem_info)
272 {
273 	struct hlist_head *hash_bucket_head;
274 	unsigned long flags;
275 
276 	spin_lock_irqsave(&iwpm_reminfo_lock, flags);
277 	if (iwpm_reminfo_bucket) {
278 		hash_bucket_head = get_reminfo_hash_bucket(
279 					&rem_info->mapped_loc_sockaddr,
280 					&rem_info->mapped_rem_sockaddr);
281 		if (hash_bucket_head)
282 			hlist_add_head(&rem_info->hlist_node, hash_bucket_head);
283 	}
284 	spin_unlock_irqrestore(&iwpm_reminfo_lock, flags);
285 }
286 
287 /**
288  * iwpm_get_remote_info - Get the remote connecting peer address info
289  *
290  * @mapped_loc_addr: Mapped local address of the listening peer
291  * @mapped_rem_addr: Mapped remote address of the connecting peer
292  * @remote_addr: To store the remote address of the connecting peer
293  * @nl_client: The index of the netlink client
294  *
295  * The remote address info is retrieved and provided to the client in
296  * the remote_addr. After that it is removed from the hash table
297  */
298 int iwpm_get_remote_info(struct sockaddr_storage *mapped_loc_addr,
299 			 struct sockaddr_storage *mapped_rem_addr,
300 			 struct sockaddr_storage *remote_addr,
301 			 u8 nl_client)
302 {
303 	struct hlist_node *tmp_hlist_node;
304 	struct hlist_head *hash_bucket_head;
305 	struct iwpm_remote_info *rem_info = NULL;
306 	unsigned long flags;
307 	int ret = -EINVAL;
308 
309 	if (!iwpm_valid_client(nl_client)) {
310 		pr_info("%s: Invalid client = %u\n", __func__, nl_client);
311 		return ret;
312 	}
313 	spin_lock_irqsave(&iwpm_reminfo_lock, flags);
314 	if (iwpm_reminfo_bucket) {
315 		hash_bucket_head = get_reminfo_hash_bucket(
316 					mapped_loc_addr,
317 					mapped_rem_addr);
318 		if (!hash_bucket_head)
319 			goto get_remote_info_exit;
320 		hlist_for_each_entry_safe(rem_info, tmp_hlist_node,
321 					hash_bucket_head, hlist_node) {
322 
323 			if (!iwpm_compare_sockaddr(&rem_info->mapped_loc_sockaddr,
324 				mapped_loc_addr) &&
325 				!iwpm_compare_sockaddr(&rem_info->mapped_rem_sockaddr,
326 				mapped_rem_addr)) {
327 
328 				memcpy(remote_addr, &rem_info->remote_sockaddr,
329 					sizeof(struct sockaddr_storage));
330 				iwpm_print_sockaddr(remote_addr,
331 						"get_remote_info: Remote sockaddr:");
332 
333 				hlist_del_init(&rem_info->hlist_node);
334 				kfree(rem_info);
335 				ret = 0;
336 				break;
337 			}
338 		}
339 	}
340 get_remote_info_exit:
341 	spin_unlock_irqrestore(&iwpm_reminfo_lock, flags);
342 	return ret;
343 }
344 
345 struct iwpm_nlmsg_request *iwpm_get_nlmsg_request(__u32 nlmsg_seq,
346 					u8 nl_client, gfp_t gfp)
347 {
348 	struct iwpm_nlmsg_request *nlmsg_request = NULL;
349 	unsigned long flags;
350 
351 	nlmsg_request = kzalloc(sizeof(struct iwpm_nlmsg_request), gfp);
352 	if (!nlmsg_request)
353 		return NULL;
354 
355 	spin_lock_irqsave(&iwpm_nlmsg_req_lock, flags);
356 	list_add_tail(&nlmsg_request->inprocess_list, &iwpm_nlmsg_req_list);
357 	spin_unlock_irqrestore(&iwpm_nlmsg_req_lock, flags);
358 
359 	kref_init(&nlmsg_request->kref);
360 	kref_get(&nlmsg_request->kref);
361 	nlmsg_request->nlmsg_seq = nlmsg_seq;
362 	nlmsg_request->nl_client = nl_client;
363 	nlmsg_request->request_done = 0;
364 	nlmsg_request->err_code = 0;
365 	sema_init(&nlmsg_request->sem, 1);
366 	down(&nlmsg_request->sem);
367 	return nlmsg_request;
368 }
369 
370 void iwpm_free_nlmsg_request(struct kref *kref)
371 {
372 	struct iwpm_nlmsg_request *nlmsg_request;
373 	unsigned long flags;
374 
375 	nlmsg_request = container_of(kref, struct iwpm_nlmsg_request, kref);
376 
377 	spin_lock_irqsave(&iwpm_nlmsg_req_lock, flags);
378 	list_del_init(&nlmsg_request->inprocess_list);
379 	spin_unlock_irqrestore(&iwpm_nlmsg_req_lock, flags);
380 
381 	if (!nlmsg_request->request_done)
382 		pr_debug("%s Freeing incomplete nlmsg request (seq = %u).\n",
383 			__func__, nlmsg_request->nlmsg_seq);
384 	kfree(nlmsg_request);
385 }
386 
387 struct iwpm_nlmsg_request *iwpm_find_nlmsg_request(__u32 echo_seq)
388 {
389 	struct iwpm_nlmsg_request *nlmsg_request;
390 	struct iwpm_nlmsg_request *found_request = NULL;
391 	unsigned long flags;
392 
393 	spin_lock_irqsave(&iwpm_nlmsg_req_lock, flags);
394 	list_for_each_entry(nlmsg_request, &iwpm_nlmsg_req_list,
395 			    inprocess_list) {
396 		if (nlmsg_request->nlmsg_seq == echo_seq) {
397 			found_request = nlmsg_request;
398 			kref_get(&nlmsg_request->kref);
399 			break;
400 		}
401 	}
402 	spin_unlock_irqrestore(&iwpm_nlmsg_req_lock, flags);
403 	return found_request;
404 }
405 
406 int iwpm_wait_complete_req(struct iwpm_nlmsg_request *nlmsg_request)
407 {
408 	int ret;
409 
410 	ret = down_timeout(&nlmsg_request->sem, IWPM_NL_TIMEOUT);
411 	if (ret) {
412 		ret = -EINVAL;
413 		pr_info("%s: Timeout %d sec for netlink request (seq = %u)\n",
414 			__func__, (IWPM_NL_TIMEOUT/HZ), nlmsg_request->nlmsg_seq);
415 	} else {
416 		ret = nlmsg_request->err_code;
417 	}
418 	kref_put(&nlmsg_request->kref, iwpm_free_nlmsg_request);
419 	return ret;
420 }
421 
422 int iwpm_get_nlmsg_seq(void)
423 {
424 	return atomic_inc_return(&iwpm_admin.nlmsg_seq);
425 }
426 
427 int iwpm_valid_client(u8 nl_client)
428 {
429 	return iwpm_admin.client_list[nl_client];
430 }
431 
432 void iwpm_set_valid(u8 nl_client, int valid)
433 {
434 	iwpm_admin.client_list[nl_client] = valid;
435 }
436 
437 /* valid client */
438 u32 iwpm_get_registration(u8 nl_client)
439 {
440 	return iwpm_admin.reg_list[nl_client];
441 }
442 
443 /* valid client */
444 void iwpm_set_registration(u8 nl_client, u32 reg)
445 {
446 	iwpm_admin.reg_list[nl_client] = reg;
447 }
448 
449 /* valid client */
450 u32 iwpm_check_registration(u8 nl_client, u32 reg)
451 {
452 	return (iwpm_get_registration(nl_client) & reg);
453 }
454 
455 int iwpm_compare_sockaddr(struct sockaddr_storage *a_sockaddr,
456 				struct sockaddr_storage *b_sockaddr)
457 {
458 	if (a_sockaddr->ss_family != b_sockaddr->ss_family)
459 		return 1;
460 	if (a_sockaddr->ss_family == AF_INET) {
461 		struct sockaddr_in *a4_sockaddr =
462 			(struct sockaddr_in *)a_sockaddr;
463 		struct sockaddr_in *b4_sockaddr =
464 			(struct sockaddr_in *)b_sockaddr;
465 		if (!memcmp(&a4_sockaddr->sin_addr,
466 			&b4_sockaddr->sin_addr, sizeof(struct in_addr))
467 			&& a4_sockaddr->sin_port == b4_sockaddr->sin_port)
468 				return 0;
469 
470 	} else if (a_sockaddr->ss_family == AF_INET6) {
471 		struct sockaddr_in6 *a6_sockaddr =
472 			(struct sockaddr_in6 *)a_sockaddr;
473 		struct sockaddr_in6 *b6_sockaddr =
474 			(struct sockaddr_in6 *)b_sockaddr;
475 		if (!memcmp(&a6_sockaddr->sin6_addr,
476 			&b6_sockaddr->sin6_addr, sizeof(struct in6_addr))
477 			&& a6_sockaddr->sin6_port == b6_sockaddr->sin6_port)
478 				return 0;
479 
480 	} else {
481 		pr_err("%s: Invalid sockaddr family\n", __func__);
482 	}
483 	return 1;
484 }
485 
486 struct sk_buff *iwpm_create_nlmsg(u32 nl_op, struct nlmsghdr **nlh,
487 						int nl_client)
488 {
489 	struct sk_buff *skb = NULL;
490 
491 	skb = dev_alloc_skb(IWPM_MSG_SIZE);
492 	if (!skb)
493 		goto create_nlmsg_exit;
494 
495 	if (!(ibnl_put_msg(skb, nlh, 0, 0, nl_client, nl_op,
496 			   NLM_F_REQUEST))) {
497 		pr_warn("%s: Unable to put the nlmsg header\n", __func__);
498 		dev_kfree_skb(skb);
499 		skb = NULL;
500 	}
501 create_nlmsg_exit:
502 	return skb;
503 }
504 
505 int iwpm_parse_nlmsg(struct netlink_callback *cb, int policy_max,
506 				   const struct nla_policy *nlmsg_policy,
507 				   struct nlattr *nltb[], const char *msg_type)
508 {
509 	int nlh_len = 0;
510 	int ret;
511 	const char *err_str = "";
512 
513 	ret = nlmsg_validate_deprecated(cb->nlh, nlh_len, policy_max - 1,
514 					nlmsg_policy, NULL);
515 	if (ret) {
516 		err_str = "Invalid attribute";
517 		goto parse_nlmsg_error;
518 	}
519 	ret = nlmsg_parse_deprecated(cb->nlh, nlh_len, nltb, policy_max - 1,
520 				     nlmsg_policy, NULL);
521 	if (ret) {
522 		err_str = "Unable to parse the nlmsg";
523 		goto parse_nlmsg_error;
524 	}
525 	ret = iwpm_validate_nlmsg_attr(nltb, policy_max);
526 	if (ret) {
527 		err_str = "Invalid NULL attribute";
528 		goto parse_nlmsg_error;
529 	}
530 	return 0;
531 parse_nlmsg_error:
532 	pr_warn("%s: %s (msg type %s ret = %d)\n",
533 			__func__, err_str, msg_type, ret);
534 	return ret;
535 }
536 
537 void iwpm_print_sockaddr(struct sockaddr_storage *sockaddr, char *msg)
538 {
539 	struct sockaddr_in6 *sockaddr_v6;
540 	struct sockaddr_in *sockaddr_v4;
541 
542 	switch (sockaddr->ss_family) {
543 	case AF_INET:
544 		sockaddr_v4 = (struct sockaddr_in *)sockaddr;
545 		pr_debug("%s IPV4 %pI4: %u(0x%04X)\n",
546 			msg, &sockaddr_v4->sin_addr,
547 			ntohs(sockaddr_v4->sin_port),
548 			ntohs(sockaddr_v4->sin_port));
549 		break;
550 	case AF_INET6:
551 		sockaddr_v6 = (struct sockaddr_in6 *)sockaddr;
552 		pr_debug("%s IPV6 %pI6: %u(0x%04X)\n",
553 			msg, &sockaddr_v6->sin6_addr,
554 			ntohs(sockaddr_v6->sin6_port),
555 			ntohs(sockaddr_v6->sin6_port));
556 		break;
557 	default:
558 		break;
559 	}
560 }
561 
562 static u32 iwpm_ipv6_jhash(struct sockaddr_in6 *ipv6_sockaddr)
563 {
564 	u32 ipv6_hash = jhash(&ipv6_sockaddr->sin6_addr, sizeof(struct in6_addr), 0);
565 	u32 hash = jhash_2words(ipv6_hash, (__force u32) ipv6_sockaddr->sin6_port, 0);
566 	return hash;
567 }
568 
569 static u32 iwpm_ipv4_jhash(struct sockaddr_in *ipv4_sockaddr)
570 {
571 	u32 ipv4_hash = jhash(&ipv4_sockaddr->sin_addr, sizeof(struct in_addr), 0);
572 	u32 hash = jhash_2words(ipv4_hash, (__force u32) ipv4_sockaddr->sin_port, 0);
573 	return hash;
574 }
575 
576 static int get_hash_bucket(struct sockaddr_storage *a_sockaddr,
577 				struct sockaddr_storage *b_sockaddr, u32 *hash)
578 {
579 	u32 a_hash, b_hash;
580 
581 	if (a_sockaddr->ss_family == AF_INET) {
582 		a_hash = iwpm_ipv4_jhash((struct sockaddr_in *) a_sockaddr);
583 		b_hash = iwpm_ipv4_jhash((struct sockaddr_in *) b_sockaddr);
584 
585 	} else if (a_sockaddr->ss_family == AF_INET6) {
586 		a_hash = iwpm_ipv6_jhash((struct sockaddr_in6 *) a_sockaddr);
587 		b_hash = iwpm_ipv6_jhash((struct sockaddr_in6 *) b_sockaddr);
588 	} else {
589 		pr_err("%s: Invalid sockaddr family\n", __func__);
590 		return -EINVAL;
591 	}
592 
593 	if (a_hash == b_hash) /* if port mapper isn't available */
594 		*hash = a_hash;
595 	else
596 		*hash = jhash_2words(a_hash, b_hash, 0);
597 	return 0;
598 }
599 
600 static struct hlist_head *get_mapinfo_hash_bucket(struct sockaddr_storage
601 				*local_sockaddr, struct sockaddr_storage
602 				*mapped_sockaddr)
603 {
604 	u32 hash;
605 	int ret;
606 
607 	ret = get_hash_bucket(local_sockaddr, mapped_sockaddr, &hash);
608 	if (ret)
609 		return NULL;
610 	return &iwpm_hash_bucket[hash & IWPM_MAPINFO_HASH_MASK];
611 }
612 
613 static struct hlist_head *get_reminfo_hash_bucket(struct sockaddr_storage
614 				*mapped_loc_sockaddr, struct sockaddr_storage
615 				*mapped_rem_sockaddr)
616 {
617 	u32 hash;
618 	int ret;
619 
620 	ret = get_hash_bucket(mapped_loc_sockaddr, mapped_rem_sockaddr, &hash);
621 	if (ret)
622 		return NULL;
623 	return &iwpm_reminfo_bucket[hash & IWPM_REMINFO_HASH_MASK];
624 }
625 
626 static int send_mapinfo_num(u32 mapping_num, u8 nl_client, int iwpm_pid)
627 {
628 	struct sk_buff *skb = NULL;
629 	struct nlmsghdr *nlh;
630 	u32 msg_seq;
631 	const char *err_str = "";
632 	int ret = -EINVAL;
633 
634 	skb = iwpm_create_nlmsg(RDMA_NL_IWPM_MAPINFO_NUM, &nlh, nl_client);
635 	if (!skb) {
636 		err_str = "Unable to create a nlmsg";
637 		goto mapinfo_num_error;
638 	}
639 	nlh->nlmsg_seq = iwpm_get_nlmsg_seq();
640 	msg_seq = 0;
641 	err_str = "Unable to put attribute of mapinfo number nlmsg";
642 	ret = ibnl_put_attr(skb, nlh, sizeof(u32), &msg_seq, IWPM_NLA_MAPINFO_SEQ);
643 	if (ret)
644 		goto mapinfo_num_error;
645 	ret = ibnl_put_attr(skb, nlh, sizeof(u32),
646 				&mapping_num, IWPM_NLA_MAPINFO_SEND_NUM);
647 	if (ret)
648 		goto mapinfo_num_error;
649 
650 	nlmsg_end(skb, nlh);
651 
652 	ret = rdma_nl_unicast(&init_net, skb, iwpm_pid);
653 	if (ret) {
654 		skb = NULL;
655 		err_str = "Unable to send a nlmsg";
656 		goto mapinfo_num_error;
657 	}
658 	pr_debug("%s: Sent mapping number = %u\n", __func__, mapping_num);
659 	return 0;
660 mapinfo_num_error:
661 	pr_info("%s: %s\n", __func__, err_str);
662 	dev_kfree_skb(skb);
663 	return ret;
664 }
665 
666 static int send_nlmsg_done(struct sk_buff *skb, u8 nl_client, int iwpm_pid)
667 {
668 	struct nlmsghdr *nlh = NULL;
669 	int ret = 0;
670 
671 	if (!skb)
672 		return ret;
673 	if (!(ibnl_put_msg(skb, &nlh, 0, 0, nl_client,
674 			   RDMA_NL_IWPM_MAPINFO, NLM_F_MULTI))) {
675 		pr_warn("%s Unable to put NLMSG_DONE\n", __func__);
676 		dev_kfree_skb(skb);
677 		return -ENOMEM;
678 	}
679 	nlh->nlmsg_type = NLMSG_DONE;
680 	ret = rdma_nl_unicast(&init_net, skb, iwpm_pid);
681 	if (ret)
682 		pr_warn("%s Unable to send a nlmsg\n", __func__);
683 	return ret;
684 }
685 
686 int iwpm_send_mapinfo(u8 nl_client, int iwpm_pid)
687 {
688 	struct iwpm_mapping_info *map_info;
689 	struct sk_buff *skb = NULL;
690 	struct nlmsghdr *nlh;
691 	int skb_num = 0, mapping_num = 0;
692 	int i = 0, nlmsg_bytes = 0;
693 	unsigned long flags;
694 	const char *err_str = "";
695 	int ret;
696 
697 	skb = dev_alloc_skb(NLMSG_GOODSIZE);
698 	if (!skb) {
699 		ret = -ENOMEM;
700 		err_str = "Unable to allocate skb";
701 		goto send_mapping_info_exit;
702 	}
703 	skb_num++;
704 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
705 	ret = -EINVAL;
706 	for (i = 0; i < IWPM_MAPINFO_HASH_SIZE; i++) {
707 		hlist_for_each_entry(map_info, &iwpm_hash_bucket[i],
708 				     hlist_node) {
709 			if (map_info->nl_client != nl_client)
710 				continue;
711 			nlh = NULL;
712 			if (!(ibnl_put_msg(skb, &nlh, 0, 0, nl_client,
713 					RDMA_NL_IWPM_MAPINFO, NLM_F_MULTI))) {
714 				ret = -ENOMEM;
715 				err_str = "Unable to put the nlmsg header";
716 				goto send_mapping_info_unlock;
717 			}
718 			err_str = "Unable to put attribute of the nlmsg";
719 			ret = ibnl_put_attr(skb, nlh,
720 					sizeof(struct sockaddr_storage),
721 					&map_info->local_sockaddr,
722 					IWPM_NLA_MAPINFO_LOCAL_ADDR);
723 			if (ret)
724 				goto send_mapping_info_unlock;
725 
726 			ret = ibnl_put_attr(skb, nlh,
727 					sizeof(struct sockaddr_storage),
728 					&map_info->mapped_sockaddr,
729 					IWPM_NLA_MAPINFO_MAPPED_ADDR);
730 			if (ret)
731 				goto send_mapping_info_unlock;
732 
733 			if (iwpm_ulib_version > IWPM_UABI_VERSION_MIN) {
734 				ret = ibnl_put_attr(skb, nlh, sizeof(u32),
735 						&map_info->map_flags,
736 						IWPM_NLA_MAPINFO_FLAGS);
737 				if (ret)
738 					goto send_mapping_info_unlock;
739 			}
740 
741 			nlmsg_end(skb, nlh);
742 
743 			iwpm_print_sockaddr(&map_info->local_sockaddr,
744 				"send_mapping_info: Local sockaddr:");
745 			iwpm_print_sockaddr(&map_info->mapped_sockaddr,
746 				"send_mapping_info: Mapped local sockaddr:");
747 			mapping_num++;
748 			nlmsg_bytes += nlh->nlmsg_len;
749 
750 			/* check if all mappings can fit in one skb */
751 			if (NLMSG_GOODSIZE - nlmsg_bytes < nlh->nlmsg_len * 2) {
752 				/* and leave room for NLMSG_DONE */
753 				nlmsg_bytes = 0;
754 				skb_num++;
755 				spin_unlock_irqrestore(&iwpm_mapinfo_lock,
756 						       flags);
757 				/* send the skb */
758 				ret = send_nlmsg_done(skb, nl_client, iwpm_pid);
759 				skb = NULL;
760 				if (ret) {
761 					err_str = "Unable to send map info";
762 					goto send_mapping_info_exit;
763 				}
764 				if (skb_num == IWPM_MAPINFO_SKB_COUNT) {
765 					ret = -ENOMEM;
766 					err_str = "Insufficient skbs for map info";
767 					goto send_mapping_info_exit;
768 				}
769 				skb = dev_alloc_skb(NLMSG_GOODSIZE);
770 				if (!skb) {
771 					ret = -ENOMEM;
772 					err_str = "Unable to allocate skb";
773 					goto send_mapping_info_exit;
774 				}
775 				spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
776 			}
777 		}
778 	}
779 send_mapping_info_unlock:
780 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
781 send_mapping_info_exit:
782 	if (ret) {
783 		pr_warn("%s: %s (ret = %d)\n", __func__, err_str, ret);
784 		dev_kfree_skb(skb);
785 		return ret;
786 	}
787 	send_nlmsg_done(skb, nl_client, iwpm_pid);
788 	return send_mapinfo_num(mapping_num, nl_client, iwpm_pid);
789 }
790 
791 int iwpm_mapinfo_available(void)
792 {
793 	unsigned long flags;
794 	int full_bucket = 0, i = 0;
795 
796 	spin_lock_irqsave(&iwpm_mapinfo_lock, flags);
797 	if (iwpm_hash_bucket) {
798 		for (i = 0; i < IWPM_MAPINFO_HASH_SIZE; i++) {
799 			if (!hlist_empty(&iwpm_hash_bucket[i])) {
800 				full_bucket = 1;
801 				break;
802 			}
803 		}
804 	}
805 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
806 	return full_bucket;
807 }
808 
809 int iwpm_send_hello(u8 nl_client, int iwpm_pid, u16 abi_version)
810 {
811 	struct sk_buff *skb = NULL;
812 	struct nlmsghdr *nlh;
813 	const char *err_str = "";
814 	int ret = -EINVAL;
815 
816 	skb = iwpm_create_nlmsg(RDMA_NL_IWPM_HELLO, &nlh, nl_client);
817 	if (!skb) {
818 		err_str = "Unable to create a nlmsg";
819 		goto hello_num_error;
820 	}
821 	nlh->nlmsg_seq = iwpm_get_nlmsg_seq();
822 	err_str = "Unable to put attribute of abi_version into nlmsg";
823 	ret = ibnl_put_attr(skb, nlh, sizeof(u16), &abi_version,
824 			    IWPM_NLA_HELLO_ABI_VERSION);
825 	if (ret)
826 		goto hello_num_error;
827 	nlmsg_end(skb, nlh);
828 
829 	ret = rdma_nl_unicast(&init_net, skb, iwpm_pid);
830 	if (ret) {
831 		skb = NULL;
832 		err_str = "Unable to send a nlmsg";
833 		goto hello_num_error;
834 	}
835 	pr_debug("%s: Sent hello abi_version = %u\n", __func__, abi_version);
836 	return 0;
837 hello_num_error:
838 	pr_info("%s: %s\n", __func__, err_str);
839 	dev_kfree_skb(skb);
840 	return ret;
841 }
842