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