xref: /linux/net/ethtool/netlink.c (revision 987b741c52c7c6c68d46fbaeb95b8d1087f10b7f)
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_FEC_GET]		= &ethnl_fec_request_ops,
248 	[ETHTOOL_MSG_TSINFO_GET]	= &ethnl_tsinfo_request_ops,
249 	[ETHTOOL_MSG_MODULE_EEPROM_GET]	= &ethnl_module_eeprom_request_ops,
250 	[ETHTOOL_MSG_STATS_GET]		= &ethnl_stats_request_ops,
251 };
252 
253 static struct ethnl_dump_ctx *ethnl_dump_context(struct netlink_callback *cb)
254 {
255 	return (struct ethnl_dump_ctx *)cb->ctx;
256 }
257 
258 /**
259  * ethnl_default_parse() - Parse request message
260  * @req_info:    pointer to structure to put data into
261  * @tb:		 parsed attributes
262  * @net:         request netns
263  * @request_ops: struct request_ops for request type
264  * @extack:      netlink extack for error reporting
265  * @require_dev: fail if no device identified in header
266  *
267  * Parse universal request header and call request specific ->parse_request()
268  * callback (if defined) to parse the rest of the message.
269  *
270  * Return: 0 on success or negative error code
271  */
272 static int ethnl_default_parse(struct ethnl_req_info *req_info,
273 			       struct nlattr **tb, struct net *net,
274 			       const struct ethnl_request_ops *request_ops,
275 			       struct netlink_ext_ack *extack, bool require_dev)
276 {
277 	int ret;
278 
279 	ret = ethnl_parse_header_dev_get(req_info, tb[request_ops->hdr_attr],
280 					 net, extack, require_dev);
281 	if (ret < 0)
282 		return ret;
283 
284 	if (request_ops->parse_request) {
285 		ret = request_ops->parse_request(req_info, tb, extack);
286 		if (ret < 0)
287 			return ret;
288 	}
289 
290 	return 0;
291 }
292 
293 /**
294  * ethnl_init_reply_data() - Initialize reply data for GET request
295  * @reply_data: pointer to embedded struct ethnl_reply_data
296  * @ops:        instance of struct ethnl_request_ops describing the layout
297  * @dev:        network device to initialize the reply for
298  *
299  * Fills the reply data part with zeros and sets the dev member. Must be called
300  * before calling the ->fill_reply() callback (for each iteration when handling
301  * dump requests).
302  */
303 static void ethnl_init_reply_data(struct ethnl_reply_data *reply_data,
304 				  const struct ethnl_request_ops *ops,
305 				  struct net_device *dev)
306 {
307 	memset(reply_data, 0, ops->reply_data_size);
308 	reply_data->dev = dev;
309 }
310 
311 /* default ->doit() handler for GET type requests */
312 static int ethnl_default_doit(struct sk_buff *skb, struct genl_info *info)
313 {
314 	struct ethnl_reply_data *reply_data = NULL;
315 	struct ethnl_req_info *req_info = NULL;
316 	const u8 cmd = info->genlhdr->cmd;
317 	const struct ethnl_request_ops *ops;
318 	struct sk_buff *rskb;
319 	void *reply_payload;
320 	int reply_len;
321 	int ret;
322 
323 	ops = ethnl_default_requests[cmd];
324 	if (WARN_ONCE(!ops, "cmd %u has no ethnl_request_ops\n", cmd))
325 		return -EOPNOTSUPP;
326 	req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
327 	if (!req_info)
328 		return -ENOMEM;
329 	reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
330 	if (!reply_data) {
331 		kfree(req_info);
332 		return -ENOMEM;
333 	}
334 
335 	ret = ethnl_default_parse(req_info, info->attrs, genl_info_net(info),
336 				  ops, info->extack, !ops->allow_nodev_do);
337 	if (ret < 0)
338 		goto err_dev;
339 	ethnl_init_reply_data(reply_data, ops, req_info->dev);
340 
341 	rtnl_lock();
342 	ret = ops->prepare_data(req_info, reply_data, info);
343 	rtnl_unlock();
344 	if (ret < 0)
345 		goto err_cleanup;
346 	ret = ops->reply_size(req_info, reply_data);
347 	if (ret < 0)
348 		goto err_cleanup;
349 	reply_len = ret + ethnl_reply_header_size();
350 	ret = -ENOMEM;
351 	rskb = ethnl_reply_init(reply_len, req_info->dev, ops->reply_cmd,
352 				ops->hdr_attr, info, &reply_payload);
353 	if (!rskb)
354 		goto err_cleanup;
355 	ret = ops->fill_reply(rskb, req_info, reply_data);
356 	if (ret < 0)
357 		goto err_msg;
358 	if (ops->cleanup_data)
359 		ops->cleanup_data(reply_data);
360 
361 	genlmsg_end(rskb, reply_payload);
362 	if (req_info->dev)
363 		dev_put(req_info->dev);
364 	kfree(reply_data);
365 	kfree(req_info);
366 	return genlmsg_reply(rskb, info);
367 
368 err_msg:
369 	WARN_ONCE(ret == -EMSGSIZE, "calculated message payload length (%d) not sufficient\n", reply_len);
370 	nlmsg_free(rskb);
371 err_cleanup:
372 	if (ops->cleanup_data)
373 		ops->cleanup_data(reply_data);
374 err_dev:
375 	if (req_info->dev)
376 		dev_put(req_info->dev);
377 	kfree(reply_data);
378 	kfree(req_info);
379 	return ret;
380 }
381 
382 static int ethnl_default_dump_one(struct sk_buff *skb, struct net_device *dev,
383 				  const struct ethnl_dump_ctx *ctx,
384 				  struct netlink_callback *cb)
385 {
386 	void *ehdr;
387 	int ret;
388 
389 	ehdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
390 			   &ethtool_genl_family, NLM_F_MULTI,
391 			   ctx->ops->reply_cmd);
392 	if (!ehdr)
393 		return -EMSGSIZE;
394 
395 	ethnl_init_reply_data(ctx->reply_data, ctx->ops, dev);
396 	rtnl_lock();
397 	ret = ctx->ops->prepare_data(ctx->req_info, ctx->reply_data, NULL);
398 	rtnl_unlock();
399 	if (ret < 0)
400 		goto out;
401 	ret = ethnl_fill_reply_header(skb, dev, ctx->ops->hdr_attr);
402 	if (ret < 0)
403 		goto out;
404 	ret = ctx->ops->fill_reply(skb, ctx->req_info, ctx->reply_data);
405 
406 out:
407 	if (ctx->ops->cleanup_data)
408 		ctx->ops->cleanup_data(ctx->reply_data);
409 	ctx->reply_data->dev = NULL;
410 	if (ret < 0)
411 		genlmsg_cancel(skb, ehdr);
412 	else
413 		genlmsg_end(skb, ehdr);
414 	return ret;
415 }
416 
417 /* Default ->dumpit() handler for GET requests. Device iteration copied from
418  * rtnl_dump_ifinfo(); we have to be more careful about device hashtable
419  * persistence as we cannot guarantee to hold RTNL lock through the whole
420  * function as rtnetnlink does.
421  */
422 static int ethnl_default_dumpit(struct sk_buff *skb,
423 				struct netlink_callback *cb)
424 {
425 	struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);
426 	struct net *net = sock_net(skb->sk);
427 	int s_idx = ctx->pos_idx;
428 	int h, idx = 0;
429 	int ret = 0;
430 
431 	rtnl_lock();
432 	for (h = ctx->pos_hash; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
433 		struct hlist_head *head;
434 		struct net_device *dev;
435 		unsigned int seq;
436 
437 		head = &net->dev_index_head[h];
438 
439 restart_chain:
440 		seq = net->dev_base_seq;
441 		cb->seq = seq;
442 		idx = 0;
443 		hlist_for_each_entry(dev, head, index_hlist) {
444 			if (idx < s_idx)
445 				goto cont;
446 			dev_hold(dev);
447 			rtnl_unlock();
448 
449 			ret = ethnl_default_dump_one(skb, dev, ctx, cb);
450 			dev_put(dev);
451 			if (ret < 0) {
452 				if (ret == -EOPNOTSUPP)
453 					goto lock_and_cont;
454 				if (likely(skb->len))
455 					ret = skb->len;
456 				goto out;
457 			}
458 lock_and_cont:
459 			rtnl_lock();
460 			if (net->dev_base_seq != seq) {
461 				s_idx = idx + 1;
462 				goto restart_chain;
463 			}
464 cont:
465 			idx++;
466 		}
467 
468 	}
469 	rtnl_unlock();
470 
471 out:
472 	ctx->pos_hash = h;
473 	ctx->pos_idx = idx;
474 	nl_dump_check_consistent(cb, nlmsg_hdr(skb));
475 
476 	return ret;
477 }
478 
479 /* generic ->start() handler for GET requests */
480 static int ethnl_default_start(struct netlink_callback *cb)
481 {
482 	const struct genl_dumpit_info *info = genl_dumpit_info(cb);
483 	struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);
484 	struct ethnl_reply_data *reply_data;
485 	const struct ethnl_request_ops *ops;
486 	struct ethnl_req_info *req_info;
487 	struct genlmsghdr *ghdr;
488 	int ret;
489 
490 	BUILD_BUG_ON(sizeof(*ctx) > sizeof(cb->ctx));
491 
492 	ghdr = nlmsg_data(cb->nlh);
493 	ops = ethnl_default_requests[ghdr->cmd];
494 	if (WARN_ONCE(!ops, "cmd %u has no ethnl_request_ops\n", ghdr->cmd))
495 		return -EOPNOTSUPP;
496 	req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
497 	if (!req_info)
498 		return -ENOMEM;
499 	reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
500 	if (!reply_data) {
501 		ret = -ENOMEM;
502 		goto free_req_info;
503 	}
504 
505 	ret = ethnl_default_parse(req_info, info->attrs, sock_net(cb->skb->sk),
506 				  ops, cb->extack, false);
507 	if (req_info->dev) {
508 		/* We ignore device specification in dump requests but as the
509 		 * same parser as for non-dump (doit) requests is used, it
510 		 * would take reference to the device if it finds one
511 		 */
512 		dev_put(req_info->dev);
513 		req_info->dev = NULL;
514 	}
515 	if (ret < 0)
516 		goto free_reply_data;
517 
518 	ctx->ops = ops;
519 	ctx->req_info = req_info;
520 	ctx->reply_data = reply_data;
521 	ctx->pos_hash = 0;
522 	ctx->pos_idx = 0;
523 
524 	return 0;
525 
526 free_reply_data:
527 	kfree(reply_data);
528 free_req_info:
529 	kfree(req_info);
530 
531 	return ret;
532 }
533 
534 /* default ->done() handler for GET requests */
535 static int ethnl_default_done(struct netlink_callback *cb)
536 {
537 	struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);
538 
539 	kfree(ctx->reply_data);
540 	kfree(ctx->req_info);
541 
542 	return 0;
543 }
544 
545 static const struct ethnl_request_ops *
546 ethnl_default_notify_ops[ETHTOOL_MSG_KERNEL_MAX + 1] = {
547 	[ETHTOOL_MSG_LINKINFO_NTF]	= &ethnl_linkinfo_request_ops,
548 	[ETHTOOL_MSG_LINKMODES_NTF]	= &ethnl_linkmodes_request_ops,
549 	[ETHTOOL_MSG_DEBUG_NTF]		= &ethnl_debug_request_ops,
550 	[ETHTOOL_MSG_WOL_NTF]		= &ethnl_wol_request_ops,
551 	[ETHTOOL_MSG_FEATURES_NTF]	= &ethnl_features_request_ops,
552 	[ETHTOOL_MSG_PRIVFLAGS_NTF]	= &ethnl_privflags_request_ops,
553 	[ETHTOOL_MSG_RINGS_NTF]		= &ethnl_rings_request_ops,
554 	[ETHTOOL_MSG_CHANNELS_NTF]	= &ethnl_channels_request_ops,
555 	[ETHTOOL_MSG_COALESCE_NTF]	= &ethnl_coalesce_request_ops,
556 	[ETHTOOL_MSG_PAUSE_NTF]		= &ethnl_pause_request_ops,
557 	[ETHTOOL_MSG_EEE_NTF]		= &ethnl_eee_request_ops,
558 	[ETHTOOL_MSG_FEC_NTF]		= &ethnl_fec_request_ops,
559 };
560 
561 /* default notification handler */
562 static void ethnl_default_notify(struct net_device *dev, unsigned int cmd,
563 				 const void *data)
564 {
565 	struct ethnl_reply_data *reply_data;
566 	const struct ethnl_request_ops *ops;
567 	struct ethnl_req_info *req_info;
568 	struct sk_buff *skb;
569 	void *reply_payload;
570 	int reply_len;
571 	int ret;
572 
573 	if (WARN_ONCE(cmd > ETHTOOL_MSG_KERNEL_MAX ||
574 		      !ethnl_default_notify_ops[cmd],
575 		      "unexpected notification type %u\n", cmd))
576 		return;
577 	ops = ethnl_default_notify_ops[cmd];
578 	req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
579 	if (!req_info)
580 		return;
581 	reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
582 	if (!reply_data) {
583 		kfree(req_info);
584 		return;
585 	}
586 
587 	req_info->dev = dev;
588 	req_info->flags |= ETHTOOL_FLAG_COMPACT_BITSETS;
589 
590 	ethnl_init_reply_data(reply_data, ops, dev);
591 	ret = ops->prepare_data(req_info, reply_data, NULL);
592 	if (ret < 0)
593 		goto err_cleanup;
594 	ret = ops->reply_size(req_info, reply_data);
595 	if (ret < 0)
596 		goto err_cleanup;
597 	reply_len = ret + ethnl_reply_header_size();
598 	ret = -ENOMEM;
599 	skb = genlmsg_new(reply_len, GFP_KERNEL);
600 	if (!skb)
601 		goto err_cleanup;
602 	reply_payload = ethnl_bcastmsg_put(skb, cmd);
603 	if (!reply_payload)
604 		goto err_skb;
605 	ret = ethnl_fill_reply_header(skb, dev, ops->hdr_attr);
606 	if (ret < 0)
607 		goto err_msg;
608 	ret = ops->fill_reply(skb, req_info, reply_data);
609 	if (ret < 0)
610 		goto err_msg;
611 	if (ops->cleanup_data)
612 		ops->cleanup_data(reply_data);
613 
614 	genlmsg_end(skb, reply_payload);
615 	kfree(reply_data);
616 	kfree(req_info);
617 	ethnl_multicast(skb, dev);
618 	return;
619 
620 err_msg:
621 	WARN_ONCE(ret == -EMSGSIZE,
622 		  "calculated message payload length (%d) not sufficient\n",
623 		  reply_len);
624 err_skb:
625 	nlmsg_free(skb);
626 err_cleanup:
627 	if (ops->cleanup_data)
628 		ops->cleanup_data(reply_data);
629 	kfree(reply_data);
630 	kfree(req_info);
631 	return;
632 }
633 
634 /* notifications */
635 
636 typedef void (*ethnl_notify_handler_t)(struct net_device *dev, unsigned int cmd,
637 				       const void *data);
638 
639 static const ethnl_notify_handler_t ethnl_notify_handlers[] = {
640 	[ETHTOOL_MSG_LINKINFO_NTF]	= ethnl_default_notify,
641 	[ETHTOOL_MSG_LINKMODES_NTF]	= ethnl_default_notify,
642 	[ETHTOOL_MSG_DEBUG_NTF]		= ethnl_default_notify,
643 	[ETHTOOL_MSG_WOL_NTF]		= ethnl_default_notify,
644 	[ETHTOOL_MSG_FEATURES_NTF]	= ethnl_default_notify,
645 	[ETHTOOL_MSG_PRIVFLAGS_NTF]	= ethnl_default_notify,
646 	[ETHTOOL_MSG_RINGS_NTF]		= ethnl_default_notify,
647 	[ETHTOOL_MSG_CHANNELS_NTF]	= ethnl_default_notify,
648 	[ETHTOOL_MSG_COALESCE_NTF]	= ethnl_default_notify,
649 	[ETHTOOL_MSG_PAUSE_NTF]		= ethnl_default_notify,
650 	[ETHTOOL_MSG_EEE_NTF]		= ethnl_default_notify,
651 	[ETHTOOL_MSG_FEC_NTF]		= ethnl_default_notify,
652 };
653 
654 void ethtool_notify(struct net_device *dev, unsigned int cmd, const void *data)
655 {
656 	if (unlikely(!ethnl_ok))
657 		return;
658 	ASSERT_RTNL();
659 
660 	if (likely(cmd < ARRAY_SIZE(ethnl_notify_handlers) &&
661 		   ethnl_notify_handlers[cmd]))
662 		ethnl_notify_handlers[cmd](dev, cmd, data);
663 	else
664 		WARN_ONCE(1, "notification %u not implemented (dev=%s)\n",
665 			  cmd, netdev_name(dev));
666 }
667 EXPORT_SYMBOL(ethtool_notify);
668 
669 static void ethnl_notify_features(struct netdev_notifier_info *info)
670 {
671 	struct net_device *dev = netdev_notifier_info_to_dev(info);
672 
673 	ethtool_notify(dev, ETHTOOL_MSG_FEATURES_NTF, NULL);
674 }
675 
676 static int ethnl_netdev_event(struct notifier_block *this, unsigned long event,
677 			      void *ptr)
678 {
679 	switch (event) {
680 	case NETDEV_FEAT_CHANGE:
681 		ethnl_notify_features(ptr);
682 		break;
683 	}
684 
685 	return NOTIFY_DONE;
686 }
687 
688 static struct notifier_block ethnl_netdev_notifier = {
689 	.notifier_call = ethnl_netdev_event,
690 };
691 
692 /* genetlink setup */
693 
694 static const struct genl_ops ethtool_genl_ops[] = {
695 	{
696 		.cmd	= ETHTOOL_MSG_STRSET_GET,
697 		.doit	= ethnl_default_doit,
698 		.start	= ethnl_default_start,
699 		.dumpit	= ethnl_default_dumpit,
700 		.done	= ethnl_default_done,
701 		.policy = ethnl_strset_get_policy,
702 		.maxattr = ARRAY_SIZE(ethnl_strset_get_policy) - 1,
703 	},
704 	{
705 		.cmd	= ETHTOOL_MSG_LINKINFO_GET,
706 		.doit	= ethnl_default_doit,
707 		.start	= ethnl_default_start,
708 		.dumpit	= ethnl_default_dumpit,
709 		.done	= ethnl_default_done,
710 		.policy = ethnl_linkinfo_get_policy,
711 		.maxattr = ARRAY_SIZE(ethnl_linkinfo_get_policy) - 1,
712 	},
713 	{
714 		.cmd	= ETHTOOL_MSG_LINKINFO_SET,
715 		.flags	= GENL_UNS_ADMIN_PERM,
716 		.doit	= ethnl_set_linkinfo,
717 		.policy = ethnl_linkinfo_set_policy,
718 		.maxattr = ARRAY_SIZE(ethnl_linkinfo_set_policy) - 1,
719 	},
720 	{
721 		.cmd	= ETHTOOL_MSG_LINKMODES_GET,
722 		.doit	= ethnl_default_doit,
723 		.start	= ethnl_default_start,
724 		.dumpit	= ethnl_default_dumpit,
725 		.done	= ethnl_default_done,
726 		.policy = ethnl_linkmodes_get_policy,
727 		.maxattr = ARRAY_SIZE(ethnl_linkmodes_get_policy) - 1,
728 	},
729 	{
730 		.cmd	= ETHTOOL_MSG_LINKMODES_SET,
731 		.flags	= GENL_UNS_ADMIN_PERM,
732 		.doit	= ethnl_set_linkmodes,
733 		.policy = ethnl_linkmodes_set_policy,
734 		.maxattr = ARRAY_SIZE(ethnl_linkmodes_set_policy) - 1,
735 	},
736 	{
737 		.cmd	= ETHTOOL_MSG_LINKSTATE_GET,
738 		.doit	= ethnl_default_doit,
739 		.start	= ethnl_default_start,
740 		.dumpit	= ethnl_default_dumpit,
741 		.done	= ethnl_default_done,
742 		.policy = ethnl_linkstate_get_policy,
743 		.maxattr = ARRAY_SIZE(ethnl_linkstate_get_policy) - 1,
744 	},
745 	{
746 		.cmd	= ETHTOOL_MSG_DEBUG_GET,
747 		.doit	= ethnl_default_doit,
748 		.start	= ethnl_default_start,
749 		.dumpit	= ethnl_default_dumpit,
750 		.done	= ethnl_default_done,
751 		.policy = ethnl_debug_get_policy,
752 		.maxattr = ARRAY_SIZE(ethnl_debug_get_policy) - 1,
753 	},
754 	{
755 		.cmd	= ETHTOOL_MSG_DEBUG_SET,
756 		.flags	= GENL_UNS_ADMIN_PERM,
757 		.doit	= ethnl_set_debug,
758 		.policy = ethnl_debug_set_policy,
759 		.maxattr = ARRAY_SIZE(ethnl_debug_set_policy) - 1,
760 	},
761 	{
762 		.cmd	= ETHTOOL_MSG_WOL_GET,
763 		.flags	= GENL_UNS_ADMIN_PERM,
764 		.doit	= ethnl_default_doit,
765 		.start	= ethnl_default_start,
766 		.dumpit	= ethnl_default_dumpit,
767 		.done	= ethnl_default_done,
768 		.policy = ethnl_wol_get_policy,
769 		.maxattr = ARRAY_SIZE(ethnl_wol_get_policy) - 1,
770 	},
771 	{
772 		.cmd	= ETHTOOL_MSG_WOL_SET,
773 		.flags	= GENL_UNS_ADMIN_PERM,
774 		.doit	= ethnl_set_wol,
775 		.policy = ethnl_wol_set_policy,
776 		.maxattr = ARRAY_SIZE(ethnl_wol_set_policy) - 1,
777 	},
778 	{
779 		.cmd	= ETHTOOL_MSG_FEATURES_GET,
780 		.doit	= ethnl_default_doit,
781 		.start	= ethnl_default_start,
782 		.dumpit	= ethnl_default_dumpit,
783 		.done	= ethnl_default_done,
784 		.policy = ethnl_features_get_policy,
785 		.maxattr = ARRAY_SIZE(ethnl_features_get_policy) - 1,
786 	},
787 	{
788 		.cmd	= ETHTOOL_MSG_FEATURES_SET,
789 		.flags	= GENL_UNS_ADMIN_PERM,
790 		.doit	= ethnl_set_features,
791 		.policy = ethnl_features_set_policy,
792 		.maxattr = ARRAY_SIZE(ethnl_features_set_policy) - 1,
793 	},
794 	{
795 		.cmd	= ETHTOOL_MSG_PRIVFLAGS_GET,
796 		.doit	= ethnl_default_doit,
797 		.start	= ethnl_default_start,
798 		.dumpit	= ethnl_default_dumpit,
799 		.done	= ethnl_default_done,
800 		.policy = ethnl_privflags_get_policy,
801 		.maxattr = ARRAY_SIZE(ethnl_privflags_get_policy) - 1,
802 	},
803 	{
804 		.cmd	= ETHTOOL_MSG_PRIVFLAGS_SET,
805 		.flags	= GENL_UNS_ADMIN_PERM,
806 		.doit	= ethnl_set_privflags,
807 		.policy = ethnl_privflags_set_policy,
808 		.maxattr = ARRAY_SIZE(ethnl_privflags_set_policy) - 1,
809 	},
810 	{
811 		.cmd	= ETHTOOL_MSG_RINGS_GET,
812 		.doit	= ethnl_default_doit,
813 		.start	= ethnl_default_start,
814 		.dumpit	= ethnl_default_dumpit,
815 		.done	= ethnl_default_done,
816 		.policy = ethnl_rings_get_policy,
817 		.maxattr = ARRAY_SIZE(ethnl_rings_get_policy) - 1,
818 	},
819 	{
820 		.cmd	= ETHTOOL_MSG_RINGS_SET,
821 		.flags	= GENL_UNS_ADMIN_PERM,
822 		.doit	= ethnl_set_rings,
823 		.policy = ethnl_rings_set_policy,
824 		.maxattr = ARRAY_SIZE(ethnl_rings_set_policy) - 1,
825 	},
826 	{
827 		.cmd	= ETHTOOL_MSG_CHANNELS_GET,
828 		.doit	= ethnl_default_doit,
829 		.start	= ethnl_default_start,
830 		.dumpit	= ethnl_default_dumpit,
831 		.done	= ethnl_default_done,
832 		.policy = ethnl_channels_get_policy,
833 		.maxattr = ARRAY_SIZE(ethnl_channels_get_policy) - 1,
834 	},
835 	{
836 		.cmd	= ETHTOOL_MSG_CHANNELS_SET,
837 		.flags	= GENL_UNS_ADMIN_PERM,
838 		.doit	= ethnl_set_channels,
839 		.policy = ethnl_channels_set_policy,
840 		.maxattr = ARRAY_SIZE(ethnl_channels_set_policy) - 1,
841 	},
842 	{
843 		.cmd	= ETHTOOL_MSG_COALESCE_GET,
844 		.doit	= ethnl_default_doit,
845 		.start	= ethnl_default_start,
846 		.dumpit	= ethnl_default_dumpit,
847 		.done	= ethnl_default_done,
848 		.policy = ethnl_coalesce_get_policy,
849 		.maxattr = ARRAY_SIZE(ethnl_coalesce_get_policy) - 1,
850 	},
851 	{
852 		.cmd	= ETHTOOL_MSG_COALESCE_SET,
853 		.flags	= GENL_UNS_ADMIN_PERM,
854 		.doit	= ethnl_set_coalesce,
855 		.policy = ethnl_coalesce_set_policy,
856 		.maxattr = ARRAY_SIZE(ethnl_coalesce_set_policy) - 1,
857 	},
858 	{
859 		.cmd	= ETHTOOL_MSG_PAUSE_GET,
860 		.doit	= ethnl_default_doit,
861 		.start	= ethnl_default_start,
862 		.dumpit	= ethnl_default_dumpit,
863 		.done	= ethnl_default_done,
864 		.policy = ethnl_pause_get_policy,
865 		.maxattr = ARRAY_SIZE(ethnl_pause_get_policy) - 1,
866 	},
867 	{
868 		.cmd	= ETHTOOL_MSG_PAUSE_SET,
869 		.flags	= GENL_UNS_ADMIN_PERM,
870 		.doit	= ethnl_set_pause,
871 		.policy = ethnl_pause_set_policy,
872 		.maxattr = ARRAY_SIZE(ethnl_pause_set_policy) - 1,
873 	},
874 	{
875 		.cmd	= ETHTOOL_MSG_EEE_GET,
876 		.doit	= ethnl_default_doit,
877 		.start	= ethnl_default_start,
878 		.dumpit	= ethnl_default_dumpit,
879 		.done	= ethnl_default_done,
880 		.policy = ethnl_eee_get_policy,
881 		.maxattr = ARRAY_SIZE(ethnl_eee_get_policy) - 1,
882 	},
883 	{
884 		.cmd	= ETHTOOL_MSG_EEE_SET,
885 		.flags	= GENL_UNS_ADMIN_PERM,
886 		.doit	= ethnl_set_eee,
887 		.policy = ethnl_eee_set_policy,
888 		.maxattr = ARRAY_SIZE(ethnl_eee_set_policy) - 1,
889 	},
890 	{
891 		.cmd	= ETHTOOL_MSG_TSINFO_GET,
892 		.doit	= ethnl_default_doit,
893 		.start	= ethnl_default_start,
894 		.dumpit	= ethnl_default_dumpit,
895 		.done	= ethnl_default_done,
896 		.policy = ethnl_tsinfo_get_policy,
897 		.maxattr = ARRAY_SIZE(ethnl_tsinfo_get_policy) - 1,
898 	},
899 	{
900 		.cmd	= ETHTOOL_MSG_CABLE_TEST_ACT,
901 		.flags	= GENL_UNS_ADMIN_PERM,
902 		.doit	= ethnl_act_cable_test,
903 		.policy = ethnl_cable_test_act_policy,
904 		.maxattr = ARRAY_SIZE(ethnl_cable_test_act_policy) - 1,
905 	},
906 	{
907 		.cmd	= ETHTOOL_MSG_CABLE_TEST_TDR_ACT,
908 		.flags	= GENL_UNS_ADMIN_PERM,
909 		.doit	= ethnl_act_cable_test_tdr,
910 		.policy = ethnl_cable_test_tdr_act_policy,
911 		.maxattr = ARRAY_SIZE(ethnl_cable_test_tdr_act_policy) - 1,
912 	},
913 	{
914 		.cmd	= ETHTOOL_MSG_TUNNEL_INFO_GET,
915 		.doit	= ethnl_tunnel_info_doit,
916 		.start	= ethnl_tunnel_info_start,
917 		.dumpit	= ethnl_tunnel_info_dumpit,
918 		.policy = ethnl_tunnel_info_get_policy,
919 		.maxattr = ARRAY_SIZE(ethnl_tunnel_info_get_policy) - 1,
920 	},
921 	{
922 		.cmd	= ETHTOOL_MSG_FEC_GET,
923 		.doit	= ethnl_default_doit,
924 		.start	= ethnl_default_start,
925 		.dumpit	= ethnl_default_dumpit,
926 		.done	= ethnl_default_done,
927 		.policy = ethnl_fec_get_policy,
928 		.maxattr = ARRAY_SIZE(ethnl_fec_get_policy) - 1,
929 	},
930 	{
931 		.cmd	= ETHTOOL_MSG_FEC_SET,
932 		.flags	= GENL_UNS_ADMIN_PERM,
933 		.doit	= ethnl_set_fec,
934 		.policy = ethnl_fec_set_policy,
935 		.maxattr = ARRAY_SIZE(ethnl_fec_set_policy) - 1,
936 	},
937 	{
938 		.cmd	= ETHTOOL_MSG_MODULE_EEPROM_GET,
939 		.flags  = GENL_UNS_ADMIN_PERM,
940 		.doit	= ethnl_default_doit,
941 		.start	= ethnl_default_start,
942 		.dumpit	= ethnl_default_dumpit,
943 		.done	= ethnl_default_done,
944 		.policy = ethnl_module_eeprom_get_policy,
945 		.maxattr = ARRAY_SIZE(ethnl_module_eeprom_get_policy) - 1,
946 	},
947 	{
948 		.cmd	= ETHTOOL_MSG_STATS_GET,
949 		.doit	= ethnl_default_doit,
950 		.start	= ethnl_default_start,
951 		.dumpit	= ethnl_default_dumpit,
952 		.done	= ethnl_default_done,
953 		.policy = ethnl_stats_get_policy,
954 		.maxattr = ARRAY_SIZE(ethnl_stats_get_policy) - 1,
955 	},
956 };
957 
958 static const struct genl_multicast_group ethtool_nl_mcgrps[] = {
959 	[ETHNL_MCGRP_MONITOR] = { .name = ETHTOOL_MCGRP_MONITOR_NAME },
960 };
961 
962 static struct genl_family ethtool_genl_family __ro_after_init = {
963 	.name		= ETHTOOL_GENL_NAME,
964 	.version	= ETHTOOL_GENL_VERSION,
965 	.netnsok	= true,
966 	.parallel_ops	= true,
967 	.ops		= ethtool_genl_ops,
968 	.n_ops		= ARRAY_SIZE(ethtool_genl_ops),
969 	.mcgrps		= ethtool_nl_mcgrps,
970 	.n_mcgrps	= ARRAY_SIZE(ethtool_nl_mcgrps),
971 };
972 
973 /* module setup */
974 
975 static int __init ethnl_init(void)
976 {
977 	int ret;
978 
979 	ret = genl_register_family(&ethtool_genl_family);
980 	if (WARN(ret < 0, "ethtool: genetlink family registration failed"))
981 		return ret;
982 	ethnl_ok = true;
983 
984 	ret = register_netdevice_notifier(&ethnl_netdev_notifier);
985 	WARN(ret < 0, "ethtool: net device notifier registration failed");
986 	return ret;
987 }
988 
989 subsys_initcall(ethnl_init);
990