xref: /openbmc/linux/net/ethtool/netlink.c (revision d9fd5a71)
1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 #include <net/sock.h>
4 #include <linux/ethtool_netlink.h>
5 #include "netlink.h"
6 
7 static struct genl_family ethtool_genl_family;
8 
9 static bool ethnl_ok __read_mostly;
10 static u32 ethnl_bcast_seq;
11 
12 #define ETHTOOL_FLAGS_BASIC (ETHTOOL_FLAG_COMPACT_BITSETS |	\
13 			     ETHTOOL_FLAG_OMIT_REPLY)
14 #define ETHTOOL_FLAGS_STATS (ETHTOOL_FLAGS_BASIC | ETHTOOL_FLAG_STATS)
15 
16 const struct nla_policy ethnl_header_policy[] = {
17 	[ETHTOOL_A_HEADER_DEV_INDEX]	= { .type = NLA_U32 },
18 	[ETHTOOL_A_HEADER_DEV_NAME]	= { .type = NLA_NUL_STRING,
19 					    .len = ALTIFNAMSIZ - 1 },
20 	[ETHTOOL_A_HEADER_FLAGS]	= NLA_POLICY_MASK(NLA_U32,
21 							  ETHTOOL_FLAGS_BASIC),
22 };
23 
24 const struct nla_policy ethnl_header_policy_stats[] = {
25 	[ETHTOOL_A_HEADER_DEV_INDEX]	= { .type = NLA_U32 },
26 	[ETHTOOL_A_HEADER_DEV_NAME]	= { .type = NLA_NUL_STRING,
27 					    .len = ALTIFNAMSIZ - 1 },
28 	[ETHTOOL_A_HEADER_FLAGS]	= NLA_POLICY_MASK(NLA_U32,
29 							  ETHTOOL_FLAGS_STATS),
30 };
31 
32 /**
33  * ethnl_parse_header_dev_get() - parse request header
34  * @req_info:    structure to put results into
35  * @header:      nest attribute with request header
36  * @net:         request netns
37  * @extack:      netlink extack for error reporting
38  * @require_dev: fail if no device identified in header
39  *
40  * Parse request header in nested attribute @nest and puts results into
41  * the structure pointed to by @req_info. Extack from @info is used for error
42  * reporting. If req_info->dev is not null on return, reference to it has
43  * been taken. If error is returned, *req_info is null initialized and no
44  * reference is held.
45  *
46  * Return: 0 on success or negative error code
47  */
48 int ethnl_parse_header_dev_get(struct ethnl_req_info *req_info,
49 			       const struct nlattr *header, struct net *net,
50 			       struct netlink_ext_ack *extack, bool require_dev)
51 {
52 	struct nlattr *tb[ARRAY_SIZE(ethnl_header_policy)];
53 	const struct nlattr *devname_attr;
54 	struct net_device *dev = NULL;
55 	u32 flags = 0;
56 	int ret;
57 
58 	if (!header) {
59 		NL_SET_ERR_MSG(extack, "request header missing");
60 		return -EINVAL;
61 	}
62 	/* No validation here, command policy should have a nested policy set
63 	 * for the header, therefore validation should have already been done.
64 	 */
65 	ret = nla_parse_nested(tb, ARRAY_SIZE(ethnl_header_policy) - 1, header,
66 			       NULL, extack);
67 	if (ret < 0)
68 		return ret;
69 	if (tb[ETHTOOL_A_HEADER_FLAGS])
70 		flags = nla_get_u32(tb[ETHTOOL_A_HEADER_FLAGS]);
71 
72 	devname_attr = tb[ETHTOOL_A_HEADER_DEV_NAME];
73 	if (tb[ETHTOOL_A_HEADER_DEV_INDEX]) {
74 		u32 ifindex = nla_get_u32(tb[ETHTOOL_A_HEADER_DEV_INDEX]);
75 
76 		dev = dev_get_by_index(net, ifindex);
77 		if (!dev) {
78 			NL_SET_ERR_MSG_ATTR(extack,
79 					    tb[ETHTOOL_A_HEADER_DEV_INDEX],
80 					    "no device matches ifindex");
81 			return -ENODEV;
82 		}
83 		/* if both ifindex and ifname are passed, they must match */
84 		if (devname_attr &&
85 		    strncmp(dev->name, nla_data(devname_attr), IFNAMSIZ)) {
86 			dev_put(dev);
87 			NL_SET_ERR_MSG_ATTR(extack, header,
88 					    "ifindex and name do not match");
89 			return -ENODEV;
90 		}
91 	} else if (devname_attr) {
92 		dev = dev_get_by_name(net, nla_data(devname_attr));
93 		if (!dev) {
94 			NL_SET_ERR_MSG_ATTR(extack, devname_attr,
95 					    "no device matches name");
96 			return -ENODEV;
97 		}
98 	} else if (require_dev) {
99 		NL_SET_ERR_MSG_ATTR(extack, header,
100 				    "neither ifindex nor name specified");
101 		return -EINVAL;
102 	}
103 
104 	if (dev && !netif_device_present(dev)) {
105 		dev_put(dev);
106 		NL_SET_ERR_MSG(extack, "device not present");
107 		return -ENODEV;
108 	}
109 
110 	req_info->dev = dev;
111 	req_info->flags = flags;
112 	return 0;
113 }
114 
115 /**
116  * ethnl_fill_reply_header() - Put common header into a reply message
117  * @skb:      skb with the message
118  * @dev:      network device to describe in header
119  * @attrtype: attribute type to use for the nest
120  *
121  * Create a nested attribute with attributes describing given network device.
122  *
123  * Return: 0 on success, error value (-EMSGSIZE only) on error
124  */
125 int ethnl_fill_reply_header(struct sk_buff *skb, struct net_device *dev,
126 			    u16 attrtype)
127 {
128 	struct nlattr *nest;
129 
130 	if (!dev)
131 		return 0;
132 	nest = nla_nest_start(skb, attrtype);
133 	if (!nest)
134 		return -EMSGSIZE;
135 
136 	if (nla_put_u32(skb, ETHTOOL_A_HEADER_DEV_INDEX, (u32)dev->ifindex) ||
137 	    nla_put_string(skb, ETHTOOL_A_HEADER_DEV_NAME, dev->name))
138 		goto nla_put_failure;
139 	/* If more attributes are put into reply header, ethnl_header_size()
140 	 * must be updated to account for them.
141 	 */
142 
143 	nla_nest_end(skb, nest);
144 	return 0;
145 
146 nla_put_failure:
147 	nla_nest_cancel(skb, nest);
148 	return -EMSGSIZE;
149 }
150 
151 /**
152  * ethnl_reply_init() - Create skb for a reply and fill device identification
153  * @payload:      payload length (without netlink and genetlink header)
154  * @dev:          device the reply is about (may be null)
155  * @cmd:          ETHTOOL_MSG_* message type for reply
156  * @hdr_attrtype: attribute type for common header
157  * @info:         genetlink info of the received packet we respond to
158  * @ehdrp:        place to store payload pointer returned by genlmsg_new()
159  *
160  * Return: pointer to allocated skb on success, NULL on error
161  */
162 struct sk_buff *ethnl_reply_init(size_t payload, struct net_device *dev, u8 cmd,
163 				 u16 hdr_attrtype, struct genl_info *info,
164 				 void **ehdrp)
165 {
166 	struct sk_buff *skb;
167 
168 	skb = genlmsg_new(payload, GFP_KERNEL);
169 	if (!skb)
170 		goto err;
171 	*ehdrp = genlmsg_put_reply(skb, info, &ethtool_genl_family, 0, cmd);
172 	if (!*ehdrp)
173 		goto err_free;
174 
175 	if (dev) {
176 		int ret;
177 
178 		ret = ethnl_fill_reply_header(skb, dev, hdr_attrtype);
179 		if (ret < 0)
180 			goto err_free;
181 	}
182 	return skb;
183 
184 err_free:
185 	nlmsg_free(skb);
186 err:
187 	if (info)
188 		GENL_SET_ERR_MSG(info, "failed to setup reply message");
189 	return NULL;
190 }
191 
192 void *ethnl_dump_put(struct sk_buff *skb, struct netlink_callback *cb, u8 cmd)
193 {
194 	return genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
195 			   &ethtool_genl_family, 0, cmd);
196 }
197 
198 void *ethnl_bcastmsg_put(struct sk_buff *skb, u8 cmd)
199 {
200 	return genlmsg_put(skb, 0, ++ethnl_bcast_seq, &ethtool_genl_family, 0,
201 			   cmd);
202 }
203 
204 int ethnl_multicast(struct sk_buff *skb, struct net_device *dev)
205 {
206 	return genlmsg_multicast_netns(&ethtool_genl_family, dev_net(dev), skb,
207 				       0, ETHNL_MCGRP_MONITOR, GFP_KERNEL);
208 }
209 
210 /* GET request helpers */
211 
212 /**
213  * struct ethnl_dump_ctx - context structure for generic dumpit() callback
214  * @ops:        request ops of currently processed message type
215  * @req_info:   parsed request header of processed request
216  * @reply_data: data needed to compose the reply
217  * @pos_hash:   saved iteration position - hashbucket
218  * @pos_idx:    saved iteration position - index
219  *
220  * These parameters are kept in struct netlink_callback as context preserved
221  * between iterations. They are initialized by ethnl_default_start() and used
222  * in ethnl_default_dumpit() and ethnl_default_done().
223  */
224 struct ethnl_dump_ctx {
225 	const struct ethnl_request_ops	*ops;
226 	struct ethnl_req_info		*req_info;
227 	struct ethnl_reply_data		*reply_data;
228 	int				pos_hash;
229 	int				pos_idx;
230 };
231 
232 static const struct ethnl_request_ops *
233 ethnl_default_requests[__ETHTOOL_MSG_USER_CNT] = {
234 	[ETHTOOL_MSG_STRSET_GET]	= &ethnl_strset_request_ops,
235 	[ETHTOOL_MSG_LINKINFO_GET]	= &ethnl_linkinfo_request_ops,
236 	[ETHTOOL_MSG_LINKMODES_GET]	= &ethnl_linkmodes_request_ops,
237 	[ETHTOOL_MSG_LINKSTATE_GET]	= &ethnl_linkstate_request_ops,
238 	[ETHTOOL_MSG_DEBUG_GET]		= &ethnl_debug_request_ops,
239 	[ETHTOOL_MSG_WOL_GET]		= &ethnl_wol_request_ops,
240 	[ETHTOOL_MSG_FEATURES_GET]	= &ethnl_features_request_ops,
241 	[ETHTOOL_MSG_PRIVFLAGS_GET]	= &ethnl_privflags_request_ops,
242 	[ETHTOOL_MSG_RINGS_GET]		= &ethnl_rings_request_ops,
243 	[ETHTOOL_MSG_CHANNELS_GET]	= &ethnl_channels_request_ops,
244 	[ETHTOOL_MSG_COALESCE_GET]	= &ethnl_coalesce_request_ops,
245 	[ETHTOOL_MSG_PAUSE_GET]		= &ethnl_pause_request_ops,
246 	[ETHTOOL_MSG_EEE_GET]		= &ethnl_eee_request_ops,
247 	[ETHTOOL_MSG_TSINFO_GET]	= &ethnl_tsinfo_request_ops,
248 };
249 
250 static struct ethnl_dump_ctx *ethnl_dump_context(struct netlink_callback *cb)
251 {
252 	return (struct ethnl_dump_ctx *)cb->ctx;
253 }
254 
255 /**
256  * ethnl_default_parse() - Parse request message
257  * @req_info:    pointer to structure to put data into
258  * @tb:		 parsed attributes
259  * @net:         request netns
260  * @request_ops: struct request_ops for request type
261  * @extack:      netlink extack for error reporting
262  * @require_dev: fail if no device identified in header
263  *
264  * Parse universal request header and call request specific ->parse_request()
265  * callback (if defined) to parse the rest of the message.
266  *
267  * Return: 0 on success or negative error code
268  */
269 static int ethnl_default_parse(struct ethnl_req_info *req_info,
270 			       struct nlattr **tb, struct net *net,
271 			       const struct ethnl_request_ops *request_ops,
272 			       struct netlink_ext_ack *extack, bool require_dev)
273 {
274 	int ret;
275 
276 	ret = ethnl_parse_header_dev_get(req_info, tb[request_ops->hdr_attr],
277 					 net, extack, require_dev);
278 	if (ret < 0)
279 		return ret;
280 
281 	if (request_ops->parse_request) {
282 		ret = request_ops->parse_request(req_info, tb, extack);
283 		if (ret < 0)
284 			return ret;
285 	}
286 
287 	return 0;
288 }
289 
290 /**
291  * ethnl_init_reply_data() - Initialize reply data for GET request
292  * @reply_data: pointer to embedded struct ethnl_reply_data
293  * @ops:        instance of struct ethnl_request_ops describing the layout
294  * @dev:        network device to initialize the reply for
295  *
296  * Fills the reply data part with zeros and sets the dev member. Must be called
297  * before calling the ->fill_reply() callback (for each iteration when handling
298  * dump requests).
299  */
300 static void ethnl_init_reply_data(struct ethnl_reply_data *reply_data,
301 				  const struct ethnl_request_ops *ops,
302 				  struct net_device *dev)
303 {
304 	memset(reply_data, 0, ops->reply_data_size);
305 	reply_data->dev = dev;
306 }
307 
308 /* default ->doit() handler for GET type requests */
309 static int ethnl_default_doit(struct sk_buff *skb, struct genl_info *info)
310 {
311 	struct ethnl_reply_data *reply_data = NULL;
312 	struct ethnl_req_info *req_info = NULL;
313 	const u8 cmd = info->genlhdr->cmd;
314 	const struct ethnl_request_ops *ops;
315 	struct sk_buff *rskb;
316 	void *reply_payload;
317 	int reply_len;
318 	int ret;
319 
320 	ops = ethnl_default_requests[cmd];
321 	if (WARN_ONCE(!ops, "cmd %u has no ethnl_request_ops\n", cmd))
322 		return -EOPNOTSUPP;
323 	req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
324 	if (!req_info)
325 		return -ENOMEM;
326 	reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
327 	if (!reply_data) {
328 		kfree(req_info);
329 		return -ENOMEM;
330 	}
331 
332 	ret = ethnl_default_parse(req_info, info->attrs, genl_info_net(info),
333 				  ops, info->extack, !ops->allow_nodev_do);
334 	if (ret < 0)
335 		goto err_dev;
336 	ethnl_init_reply_data(reply_data, ops, req_info->dev);
337 
338 	rtnl_lock();
339 	ret = ops->prepare_data(req_info, reply_data, info);
340 	rtnl_unlock();
341 	if (ret < 0)
342 		goto err_cleanup;
343 	ret = ops->reply_size(req_info, reply_data);
344 	if (ret < 0)
345 		goto err_cleanup;
346 	reply_len = ret + ethnl_reply_header_size();
347 	ret = -ENOMEM;
348 	rskb = ethnl_reply_init(reply_len, req_info->dev, ops->reply_cmd,
349 				ops->hdr_attr, info, &reply_payload);
350 	if (!rskb)
351 		goto err_cleanup;
352 	ret = ops->fill_reply(rskb, req_info, reply_data);
353 	if (ret < 0)
354 		goto err_msg;
355 	if (ops->cleanup_data)
356 		ops->cleanup_data(reply_data);
357 
358 	genlmsg_end(rskb, reply_payload);
359 	if (req_info->dev)
360 		dev_put(req_info->dev);
361 	kfree(reply_data);
362 	kfree(req_info);
363 	return genlmsg_reply(rskb, info);
364 
365 err_msg:
366 	WARN_ONCE(ret == -EMSGSIZE, "calculated message payload length (%d) not sufficient\n", reply_len);
367 	nlmsg_free(rskb);
368 err_cleanup:
369 	if (ops->cleanup_data)
370 		ops->cleanup_data(reply_data);
371 err_dev:
372 	if (req_info->dev)
373 		dev_put(req_info->dev);
374 	kfree(reply_data);
375 	kfree(req_info);
376 	return ret;
377 }
378 
379 static int ethnl_default_dump_one(struct sk_buff *skb, struct net_device *dev,
380 				  const struct ethnl_dump_ctx *ctx,
381 				  struct netlink_callback *cb)
382 {
383 	void *ehdr;
384 	int ret;
385 
386 	ehdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
387 			   &ethtool_genl_family, 0, ctx->ops->reply_cmd);
388 	if (!ehdr)
389 		return -EMSGSIZE;
390 
391 	ethnl_init_reply_data(ctx->reply_data, ctx->ops, dev);
392 	rtnl_lock();
393 	ret = ctx->ops->prepare_data(ctx->req_info, ctx->reply_data, NULL);
394 	rtnl_unlock();
395 	if (ret < 0)
396 		goto out;
397 	ret = ethnl_fill_reply_header(skb, dev, ctx->ops->hdr_attr);
398 	if (ret < 0)
399 		goto out;
400 	ret = ctx->ops->fill_reply(skb, ctx->req_info, ctx->reply_data);
401 
402 out:
403 	if (ctx->ops->cleanup_data)
404 		ctx->ops->cleanup_data(ctx->reply_data);
405 	ctx->reply_data->dev = NULL;
406 	if (ret < 0)
407 		genlmsg_cancel(skb, ehdr);
408 	else
409 		genlmsg_end(skb, ehdr);
410 	return ret;
411 }
412 
413 /* Default ->dumpit() handler for GET requests. Device iteration copied from
414  * rtnl_dump_ifinfo(); we have to be more careful about device hashtable
415  * persistence as we cannot guarantee to hold RTNL lock through the whole
416  * function as rtnetnlink does.
417  */
418 static int ethnl_default_dumpit(struct sk_buff *skb,
419 				struct netlink_callback *cb)
420 {
421 	struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);
422 	struct net *net = sock_net(skb->sk);
423 	int s_idx = ctx->pos_idx;
424 	int h, idx = 0;
425 	int ret = 0;
426 
427 	rtnl_lock();
428 	for (h = ctx->pos_hash; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
429 		struct hlist_head *head;
430 		struct net_device *dev;
431 		unsigned int seq;
432 
433 		head = &net->dev_index_head[h];
434 
435 restart_chain:
436 		seq = net->dev_base_seq;
437 		cb->seq = seq;
438 		idx = 0;
439 		hlist_for_each_entry(dev, head, index_hlist) {
440 			if (idx < s_idx)
441 				goto cont;
442 			dev_hold(dev);
443 			rtnl_unlock();
444 
445 			ret = ethnl_default_dump_one(skb, dev, ctx, cb);
446 			dev_put(dev);
447 			if (ret < 0) {
448 				if (ret == -EOPNOTSUPP)
449 					goto lock_and_cont;
450 				if (likely(skb->len))
451 					ret = skb->len;
452 				goto out;
453 			}
454 lock_and_cont:
455 			rtnl_lock();
456 			if (net->dev_base_seq != seq) {
457 				s_idx = idx + 1;
458 				goto restart_chain;
459 			}
460 cont:
461 			idx++;
462 		}
463 
464 	}
465 	rtnl_unlock();
466 
467 out:
468 	ctx->pos_hash = h;
469 	ctx->pos_idx = idx;
470 	nl_dump_check_consistent(cb, nlmsg_hdr(skb));
471 
472 	return ret;
473 }
474 
475 /* generic ->start() handler for GET requests */
476 static int ethnl_default_start(struct netlink_callback *cb)
477 {
478 	const struct genl_dumpit_info *info = genl_dumpit_info(cb);
479 	struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);
480 	struct ethnl_reply_data *reply_data;
481 	const struct ethnl_request_ops *ops;
482 	struct ethnl_req_info *req_info;
483 	struct genlmsghdr *ghdr;
484 	int ret;
485 
486 	BUILD_BUG_ON(sizeof(*ctx) > sizeof(cb->ctx));
487 
488 	ghdr = nlmsg_data(cb->nlh);
489 	ops = ethnl_default_requests[ghdr->cmd];
490 	if (WARN_ONCE(!ops, "cmd %u has no ethnl_request_ops\n", ghdr->cmd))
491 		return -EOPNOTSUPP;
492 	req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
493 	if (!req_info)
494 		return -ENOMEM;
495 	reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
496 	if (!reply_data) {
497 		ret = -ENOMEM;
498 		goto free_req_info;
499 	}
500 
501 	ret = ethnl_default_parse(req_info, info->attrs, sock_net(cb->skb->sk),
502 				  ops, cb->extack, false);
503 	if (req_info->dev) {
504 		/* We ignore device specification in dump requests but as the
505 		 * same parser as for non-dump (doit) requests is used, it
506 		 * would take reference to the device if it finds one
507 		 */
508 		dev_put(req_info->dev);
509 		req_info->dev = NULL;
510 	}
511 	if (ret < 0)
512 		goto free_reply_data;
513 
514 	ctx->ops = ops;
515 	ctx->req_info = req_info;
516 	ctx->reply_data = reply_data;
517 	ctx->pos_hash = 0;
518 	ctx->pos_idx = 0;
519 
520 	return 0;
521 
522 free_reply_data:
523 	kfree(reply_data);
524 free_req_info:
525 	kfree(req_info);
526 
527 	return ret;
528 }
529 
530 /* default ->done() handler for GET requests */
531 static int ethnl_default_done(struct netlink_callback *cb)
532 {
533 	struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);
534 
535 	kfree(ctx->reply_data);
536 	kfree(ctx->req_info);
537 
538 	return 0;
539 }
540 
541 static const struct ethnl_request_ops *
542 ethnl_default_notify_ops[ETHTOOL_MSG_KERNEL_MAX + 1] = {
543 	[ETHTOOL_MSG_LINKINFO_NTF]	= &ethnl_linkinfo_request_ops,
544 	[ETHTOOL_MSG_LINKMODES_NTF]	= &ethnl_linkmodes_request_ops,
545 	[ETHTOOL_MSG_DEBUG_NTF]		= &ethnl_debug_request_ops,
546 	[ETHTOOL_MSG_WOL_NTF]		= &ethnl_wol_request_ops,
547 	[ETHTOOL_MSG_FEATURES_NTF]	= &ethnl_features_request_ops,
548 	[ETHTOOL_MSG_PRIVFLAGS_NTF]	= &ethnl_privflags_request_ops,
549 	[ETHTOOL_MSG_RINGS_NTF]		= &ethnl_rings_request_ops,
550 	[ETHTOOL_MSG_CHANNELS_NTF]	= &ethnl_channels_request_ops,
551 	[ETHTOOL_MSG_COALESCE_NTF]	= &ethnl_coalesce_request_ops,
552 	[ETHTOOL_MSG_PAUSE_NTF]		= &ethnl_pause_request_ops,
553 	[ETHTOOL_MSG_EEE_NTF]		= &ethnl_eee_request_ops,
554 };
555 
556 /* default notification handler */
557 static void ethnl_default_notify(struct net_device *dev, unsigned int cmd,
558 				 const void *data)
559 {
560 	struct ethnl_reply_data *reply_data;
561 	const struct ethnl_request_ops *ops;
562 	struct ethnl_req_info *req_info;
563 	struct sk_buff *skb;
564 	void *reply_payload;
565 	int reply_len;
566 	int ret;
567 
568 	if (WARN_ONCE(cmd > ETHTOOL_MSG_KERNEL_MAX ||
569 		      !ethnl_default_notify_ops[cmd],
570 		      "unexpected notification type %u\n", cmd))
571 		return;
572 	ops = ethnl_default_notify_ops[cmd];
573 	req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
574 	if (!req_info)
575 		return;
576 	reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
577 	if (!reply_data) {
578 		kfree(req_info);
579 		return;
580 	}
581 
582 	req_info->dev = dev;
583 	req_info->flags |= ETHTOOL_FLAG_COMPACT_BITSETS;
584 
585 	ethnl_init_reply_data(reply_data, ops, dev);
586 	ret = ops->prepare_data(req_info, reply_data, NULL);
587 	if (ret < 0)
588 		goto err_cleanup;
589 	ret = ops->reply_size(req_info, reply_data);
590 	if (ret < 0)
591 		goto err_cleanup;
592 	reply_len = ret + ethnl_reply_header_size();
593 	ret = -ENOMEM;
594 	skb = genlmsg_new(reply_len, GFP_KERNEL);
595 	if (!skb)
596 		goto err_cleanup;
597 	reply_payload = ethnl_bcastmsg_put(skb, cmd);
598 	if (!reply_payload)
599 		goto err_skb;
600 	ret = ethnl_fill_reply_header(skb, dev, ops->hdr_attr);
601 	if (ret < 0)
602 		goto err_msg;
603 	ret = ops->fill_reply(skb, req_info, reply_data);
604 	if (ret < 0)
605 		goto err_msg;
606 	if (ops->cleanup_data)
607 		ops->cleanup_data(reply_data);
608 
609 	genlmsg_end(skb, reply_payload);
610 	kfree(reply_data);
611 	kfree(req_info);
612 	ethnl_multicast(skb, dev);
613 	return;
614 
615 err_msg:
616 	WARN_ONCE(ret == -EMSGSIZE,
617 		  "calculated message payload length (%d) not sufficient\n",
618 		  reply_len);
619 err_skb:
620 	nlmsg_free(skb);
621 err_cleanup:
622 	if (ops->cleanup_data)
623 		ops->cleanup_data(reply_data);
624 	kfree(reply_data);
625 	kfree(req_info);
626 	return;
627 }
628 
629 /* notifications */
630 
631 typedef void (*ethnl_notify_handler_t)(struct net_device *dev, unsigned int cmd,
632 				       const void *data);
633 
634 static const ethnl_notify_handler_t ethnl_notify_handlers[] = {
635 	[ETHTOOL_MSG_LINKINFO_NTF]	= ethnl_default_notify,
636 	[ETHTOOL_MSG_LINKMODES_NTF]	= ethnl_default_notify,
637 	[ETHTOOL_MSG_DEBUG_NTF]		= ethnl_default_notify,
638 	[ETHTOOL_MSG_WOL_NTF]		= ethnl_default_notify,
639 	[ETHTOOL_MSG_FEATURES_NTF]	= ethnl_default_notify,
640 	[ETHTOOL_MSG_PRIVFLAGS_NTF]	= ethnl_default_notify,
641 	[ETHTOOL_MSG_RINGS_NTF]		= ethnl_default_notify,
642 	[ETHTOOL_MSG_CHANNELS_NTF]	= ethnl_default_notify,
643 	[ETHTOOL_MSG_COALESCE_NTF]	= ethnl_default_notify,
644 	[ETHTOOL_MSG_PAUSE_NTF]		= ethnl_default_notify,
645 	[ETHTOOL_MSG_EEE_NTF]		= ethnl_default_notify,
646 };
647 
648 void ethtool_notify(struct net_device *dev, unsigned int cmd, const void *data)
649 {
650 	if (unlikely(!ethnl_ok))
651 		return;
652 	ASSERT_RTNL();
653 
654 	if (likely(cmd < ARRAY_SIZE(ethnl_notify_handlers) &&
655 		   ethnl_notify_handlers[cmd]))
656 		ethnl_notify_handlers[cmd](dev, cmd, data);
657 	else
658 		WARN_ONCE(1, "notification %u not implemented (dev=%s)\n",
659 			  cmd, netdev_name(dev));
660 }
661 EXPORT_SYMBOL(ethtool_notify);
662 
663 static void ethnl_notify_features(struct netdev_notifier_info *info)
664 {
665 	struct net_device *dev = netdev_notifier_info_to_dev(info);
666 
667 	ethtool_notify(dev, ETHTOOL_MSG_FEATURES_NTF, NULL);
668 }
669 
670 static int ethnl_netdev_event(struct notifier_block *this, unsigned long event,
671 			      void *ptr)
672 {
673 	switch (event) {
674 	case NETDEV_FEAT_CHANGE:
675 		ethnl_notify_features(ptr);
676 		break;
677 	}
678 
679 	return NOTIFY_DONE;
680 }
681 
682 static struct notifier_block ethnl_netdev_notifier = {
683 	.notifier_call = ethnl_netdev_event,
684 };
685 
686 /* genetlink setup */
687 
688 static const struct genl_ops ethtool_genl_ops[] = {
689 	{
690 		.cmd	= ETHTOOL_MSG_STRSET_GET,
691 		.doit	= ethnl_default_doit,
692 		.start	= ethnl_default_start,
693 		.dumpit	= ethnl_default_dumpit,
694 		.done	= ethnl_default_done,
695 		.policy = ethnl_strset_get_policy,
696 		.maxattr = ARRAY_SIZE(ethnl_strset_get_policy) - 1,
697 	},
698 	{
699 		.cmd	= ETHTOOL_MSG_LINKINFO_GET,
700 		.doit	= ethnl_default_doit,
701 		.start	= ethnl_default_start,
702 		.dumpit	= ethnl_default_dumpit,
703 		.done	= ethnl_default_done,
704 		.policy = ethnl_linkinfo_get_policy,
705 		.maxattr = ARRAY_SIZE(ethnl_linkinfo_get_policy) - 1,
706 	},
707 	{
708 		.cmd	= ETHTOOL_MSG_LINKINFO_SET,
709 		.flags	= GENL_UNS_ADMIN_PERM,
710 		.doit	= ethnl_set_linkinfo,
711 		.policy = ethnl_linkinfo_set_policy,
712 		.maxattr = ARRAY_SIZE(ethnl_linkinfo_set_policy) - 1,
713 	},
714 	{
715 		.cmd	= ETHTOOL_MSG_LINKMODES_GET,
716 		.doit	= ethnl_default_doit,
717 		.start	= ethnl_default_start,
718 		.dumpit	= ethnl_default_dumpit,
719 		.done	= ethnl_default_done,
720 		.policy = ethnl_linkmodes_get_policy,
721 		.maxattr = ARRAY_SIZE(ethnl_linkmodes_get_policy) - 1,
722 	},
723 	{
724 		.cmd	= ETHTOOL_MSG_LINKMODES_SET,
725 		.flags	= GENL_UNS_ADMIN_PERM,
726 		.doit	= ethnl_set_linkmodes,
727 		.policy = ethnl_linkmodes_set_policy,
728 		.maxattr = ARRAY_SIZE(ethnl_linkmodes_set_policy) - 1,
729 	},
730 	{
731 		.cmd	= ETHTOOL_MSG_LINKSTATE_GET,
732 		.doit	= ethnl_default_doit,
733 		.start	= ethnl_default_start,
734 		.dumpit	= ethnl_default_dumpit,
735 		.done	= ethnl_default_done,
736 		.policy = ethnl_linkstate_get_policy,
737 		.maxattr = ARRAY_SIZE(ethnl_linkstate_get_policy) - 1,
738 	},
739 	{
740 		.cmd	= ETHTOOL_MSG_DEBUG_GET,
741 		.doit	= ethnl_default_doit,
742 		.start	= ethnl_default_start,
743 		.dumpit	= ethnl_default_dumpit,
744 		.done	= ethnl_default_done,
745 		.policy = ethnl_debug_get_policy,
746 		.maxattr = ARRAY_SIZE(ethnl_debug_get_policy) - 1,
747 	},
748 	{
749 		.cmd	= ETHTOOL_MSG_DEBUG_SET,
750 		.flags	= GENL_UNS_ADMIN_PERM,
751 		.doit	= ethnl_set_debug,
752 		.policy = ethnl_debug_set_policy,
753 		.maxattr = ARRAY_SIZE(ethnl_debug_set_policy) - 1,
754 	},
755 	{
756 		.cmd	= ETHTOOL_MSG_WOL_GET,
757 		.flags	= GENL_UNS_ADMIN_PERM,
758 		.doit	= ethnl_default_doit,
759 		.start	= ethnl_default_start,
760 		.dumpit	= ethnl_default_dumpit,
761 		.done	= ethnl_default_done,
762 		.policy = ethnl_wol_get_policy,
763 		.maxattr = ARRAY_SIZE(ethnl_wol_get_policy) - 1,
764 	},
765 	{
766 		.cmd	= ETHTOOL_MSG_WOL_SET,
767 		.flags	= GENL_UNS_ADMIN_PERM,
768 		.doit	= ethnl_set_wol,
769 		.policy = ethnl_wol_set_policy,
770 		.maxattr = ARRAY_SIZE(ethnl_wol_set_policy) - 1,
771 	},
772 	{
773 		.cmd	= ETHTOOL_MSG_FEATURES_GET,
774 		.doit	= ethnl_default_doit,
775 		.start	= ethnl_default_start,
776 		.dumpit	= ethnl_default_dumpit,
777 		.done	= ethnl_default_done,
778 		.policy = ethnl_features_get_policy,
779 		.maxattr = ARRAY_SIZE(ethnl_features_get_policy) - 1,
780 	},
781 	{
782 		.cmd	= ETHTOOL_MSG_FEATURES_SET,
783 		.flags	= GENL_UNS_ADMIN_PERM,
784 		.doit	= ethnl_set_features,
785 		.policy = ethnl_features_set_policy,
786 		.maxattr = ARRAY_SIZE(ethnl_features_set_policy) - 1,
787 	},
788 	{
789 		.cmd	= ETHTOOL_MSG_PRIVFLAGS_GET,
790 		.doit	= ethnl_default_doit,
791 		.start	= ethnl_default_start,
792 		.dumpit	= ethnl_default_dumpit,
793 		.done	= ethnl_default_done,
794 		.policy = ethnl_privflags_get_policy,
795 		.maxattr = ARRAY_SIZE(ethnl_privflags_get_policy) - 1,
796 	},
797 	{
798 		.cmd	= ETHTOOL_MSG_PRIVFLAGS_SET,
799 		.flags	= GENL_UNS_ADMIN_PERM,
800 		.doit	= ethnl_set_privflags,
801 		.policy = ethnl_privflags_set_policy,
802 		.maxattr = ARRAY_SIZE(ethnl_privflags_set_policy) - 1,
803 	},
804 	{
805 		.cmd	= ETHTOOL_MSG_RINGS_GET,
806 		.doit	= ethnl_default_doit,
807 		.start	= ethnl_default_start,
808 		.dumpit	= ethnl_default_dumpit,
809 		.done	= ethnl_default_done,
810 		.policy = ethnl_rings_get_policy,
811 		.maxattr = ARRAY_SIZE(ethnl_rings_get_policy) - 1,
812 	},
813 	{
814 		.cmd	= ETHTOOL_MSG_RINGS_SET,
815 		.flags	= GENL_UNS_ADMIN_PERM,
816 		.doit	= ethnl_set_rings,
817 		.policy = ethnl_rings_set_policy,
818 		.maxattr = ARRAY_SIZE(ethnl_rings_set_policy) - 1,
819 	},
820 	{
821 		.cmd	= ETHTOOL_MSG_CHANNELS_GET,
822 		.doit	= ethnl_default_doit,
823 		.start	= ethnl_default_start,
824 		.dumpit	= ethnl_default_dumpit,
825 		.done	= ethnl_default_done,
826 		.policy = ethnl_channels_get_policy,
827 		.maxattr = ARRAY_SIZE(ethnl_channels_get_policy) - 1,
828 	},
829 	{
830 		.cmd	= ETHTOOL_MSG_CHANNELS_SET,
831 		.flags	= GENL_UNS_ADMIN_PERM,
832 		.doit	= ethnl_set_channels,
833 		.policy = ethnl_channels_set_policy,
834 		.maxattr = ARRAY_SIZE(ethnl_channels_set_policy) - 1,
835 	},
836 	{
837 		.cmd	= ETHTOOL_MSG_COALESCE_GET,
838 		.doit	= ethnl_default_doit,
839 		.start	= ethnl_default_start,
840 		.dumpit	= ethnl_default_dumpit,
841 		.done	= ethnl_default_done,
842 		.policy = ethnl_coalesce_get_policy,
843 		.maxattr = ARRAY_SIZE(ethnl_coalesce_get_policy) - 1,
844 	},
845 	{
846 		.cmd	= ETHTOOL_MSG_COALESCE_SET,
847 		.flags	= GENL_UNS_ADMIN_PERM,
848 		.doit	= ethnl_set_coalesce,
849 		.policy = ethnl_coalesce_set_policy,
850 		.maxattr = ARRAY_SIZE(ethnl_coalesce_set_policy) - 1,
851 	},
852 	{
853 		.cmd	= ETHTOOL_MSG_PAUSE_GET,
854 		.doit	= ethnl_default_doit,
855 		.start	= ethnl_default_start,
856 		.dumpit	= ethnl_default_dumpit,
857 		.done	= ethnl_default_done,
858 		.policy = ethnl_pause_get_policy,
859 		.maxattr = ARRAY_SIZE(ethnl_pause_get_policy) - 1,
860 	},
861 	{
862 		.cmd	= ETHTOOL_MSG_PAUSE_SET,
863 		.flags	= GENL_UNS_ADMIN_PERM,
864 		.doit	= ethnl_set_pause,
865 		.policy = ethnl_pause_set_policy,
866 		.maxattr = ARRAY_SIZE(ethnl_pause_set_policy) - 1,
867 	},
868 	{
869 		.cmd	= ETHTOOL_MSG_EEE_GET,
870 		.doit	= ethnl_default_doit,
871 		.start	= ethnl_default_start,
872 		.dumpit	= ethnl_default_dumpit,
873 		.done	= ethnl_default_done,
874 		.policy = ethnl_eee_get_policy,
875 		.maxattr = ARRAY_SIZE(ethnl_eee_get_policy) - 1,
876 	},
877 	{
878 		.cmd	= ETHTOOL_MSG_EEE_SET,
879 		.flags	= GENL_UNS_ADMIN_PERM,
880 		.doit	= ethnl_set_eee,
881 		.policy = ethnl_eee_set_policy,
882 		.maxattr = ARRAY_SIZE(ethnl_eee_set_policy) - 1,
883 	},
884 	{
885 		.cmd	= ETHTOOL_MSG_TSINFO_GET,
886 		.doit	= ethnl_default_doit,
887 		.start	= ethnl_default_start,
888 		.dumpit	= ethnl_default_dumpit,
889 		.done	= ethnl_default_done,
890 		.policy = ethnl_tsinfo_get_policy,
891 		.maxattr = ARRAY_SIZE(ethnl_tsinfo_get_policy) - 1,
892 	},
893 	{
894 		.cmd	= ETHTOOL_MSG_CABLE_TEST_ACT,
895 		.flags	= GENL_UNS_ADMIN_PERM,
896 		.doit	= ethnl_act_cable_test,
897 		.policy = ethnl_cable_test_act_policy,
898 		.maxattr = ARRAY_SIZE(ethnl_cable_test_act_policy) - 1,
899 	},
900 	{
901 		.cmd	= ETHTOOL_MSG_CABLE_TEST_TDR_ACT,
902 		.flags	= GENL_UNS_ADMIN_PERM,
903 		.doit	= ethnl_act_cable_test_tdr,
904 		.policy = ethnl_cable_test_tdr_act_policy,
905 		.maxattr = ARRAY_SIZE(ethnl_cable_test_tdr_act_policy) - 1,
906 	},
907 	{
908 		.cmd	= ETHTOOL_MSG_TUNNEL_INFO_GET,
909 		.doit	= ethnl_tunnel_info_doit,
910 		.start	= ethnl_tunnel_info_start,
911 		.dumpit	= ethnl_tunnel_info_dumpit,
912 		.policy = ethnl_tunnel_info_get_policy,
913 		.maxattr = ARRAY_SIZE(ethnl_tunnel_info_get_policy) - 1,
914 	},
915 };
916 
917 static const struct genl_multicast_group ethtool_nl_mcgrps[] = {
918 	[ETHNL_MCGRP_MONITOR] = { .name = ETHTOOL_MCGRP_MONITOR_NAME },
919 };
920 
921 static struct genl_family ethtool_genl_family __ro_after_init = {
922 	.name		= ETHTOOL_GENL_NAME,
923 	.version	= ETHTOOL_GENL_VERSION,
924 	.netnsok	= true,
925 	.parallel_ops	= true,
926 	.ops		= ethtool_genl_ops,
927 	.n_ops		= ARRAY_SIZE(ethtool_genl_ops),
928 	.mcgrps		= ethtool_nl_mcgrps,
929 	.n_mcgrps	= ARRAY_SIZE(ethtool_nl_mcgrps),
930 };
931 
932 /* module setup */
933 
934 static int __init ethnl_init(void)
935 {
936 	int ret;
937 
938 	ret = genl_register_family(&ethtool_genl_family);
939 	if (WARN(ret < 0, "ethtool: genetlink family registration failed"))
940 		return ret;
941 	ethnl_ok = true;
942 
943 	ret = register_netdevice_notifier(&ethnl_netdev_notifier);
944 	WARN(ret < 0, "ethtool: net device notifier registration failed");
945 	return ret;
946 }
947 
948 subsys_initcall(ethnl_init);
949