xref: /openbmc/linux/net/ethtool/netlink.h (revision a5b2c10c)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 
3 #ifndef _NET_ETHTOOL_NETLINK_H
4 #define _NET_ETHTOOL_NETLINK_H
5 
6 #include <linux/ethtool_netlink.h>
7 #include <linux/netdevice.h>
8 #include <net/genetlink.h>
9 #include <net/sock.h>
10 
11 struct ethnl_req_info;
12 
13 int ethnl_parse_header_dev_get(struct ethnl_req_info *req_info,
14 			       const struct nlattr *nest, struct net *net,
15 			       struct netlink_ext_ack *extack,
16 			       bool require_dev);
17 int ethnl_fill_reply_header(struct sk_buff *skb, struct net_device *dev,
18 			    u16 attrtype);
19 struct sk_buff *ethnl_reply_init(size_t payload, struct net_device *dev, u8 cmd,
20 				 u16 hdr_attrtype, struct genl_info *info,
21 				 void **ehdrp);
22 void *ethnl_dump_put(struct sk_buff *skb, struct netlink_callback *cb, u8 cmd);
23 void *ethnl_bcastmsg_put(struct sk_buff *skb, u8 cmd);
24 int ethnl_multicast(struct sk_buff *skb, struct net_device *dev);
25 
26 /**
27  * ethnl_strz_size() - calculate attribute length for fixed size string
28  * @s: ETH_GSTRING_LEN sized string (may not be null terminated)
29  *
30  * Return: total length of an attribute with null terminated string from @s
31  */
32 static inline int ethnl_strz_size(const char *s)
33 {
34 	return nla_total_size(strnlen(s, ETH_GSTRING_LEN) + 1);
35 }
36 
37 /**
38  * ethnl_put_strz() - put string attribute with fixed size string
39  * @skb:     skb with the message
40  * @attrype: attribute type
41  * @s:       ETH_GSTRING_LEN sized string (may not be null terminated)
42  *
43  * Puts an attribute with null terminated string from @s into the message.
44  *
45  * Return: 0 on success, negative error code on failure
46  */
47 static inline int ethnl_put_strz(struct sk_buff *skb, u16 attrtype,
48 				 const char *s)
49 {
50 	unsigned int len = strnlen(s, ETH_GSTRING_LEN);
51 	struct nlattr *attr;
52 
53 	attr = nla_reserve(skb, attrtype, len + 1);
54 	if (!attr)
55 		return -EMSGSIZE;
56 
57 	memcpy(nla_data(attr), s, len);
58 	((char *)nla_data(attr))[len] = '\0';
59 	return 0;
60 }
61 
62 /**
63  * ethnl_update_u32() - update u32 value from NLA_U32 attribute
64  * @dst:  value to update
65  * @attr: netlink attribute with new value or null
66  * @mod:  pointer to bool for modification tracking
67  *
68  * Copy the u32 value from NLA_U32 netlink attribute @attr into variable
69  * pointed to by @dst; do nothing if @attr is null. Bool pointed to by @mod
70  * is set to true if this function changed the value of *dst, otherwise it
71  * is left as is.
72  */
73 static inline void ethnl_update_u32(u32 *dst, const struct nlattr *attr,
74 				    bool *mod)
75 {
76 	u32 val;
77 
78 	if (!attr)
79 		return;
80 	val = nla_get_u32(attr);
81 	if (*dst == val)
82 		return;
83 
84 	*dst = val;
85 	*mod = true;
86 }
87 
88 /**
89  * ethnl_update_u8() - update u8 value from NLA_U8 attribute
90  * @dst:  value to update
91  * @attr: netlink attribute with new value or null
92  * @mod:  pointer to bool for modification tracking
93  *
94  * Copy the u8 value from NLA_U8 netlink attribute @attr into variable
95  * pointed to by @dst; do nothing if @attr is null. Bool pointed to by @mod
96  * is set to true if this function changed the value of *dst, otherwise it
97  * is left as is.
98  */
99 static inline void ethnl_update_u8(u8 *dst, const struct nlattr *attr,
100 				   bool *mod)
101 {
102 	u8 val;
103 
104 	if (!attr)
105 		return;
106 	val = nla_get_u8(attr);
107 	if (*dst == val)
108 		return;
109 
110 	*dst = val;
111 	*mod = true;
112 }
113 
114 /**
115  * ethnl_update_bool32() - update u32 used as bool from NLA_U8 attribute
116  * @dst:  value to update
117  * @attr: netlink attribute with new value or null
118  * @mod:  pointer to bool for modification tracking
119  *
120  * Use the u8 value from NLA_U8 netlink attribute @attr to set u32 variable
121  * pointed to by @dst to 0 (if zero) or 1 (if not); do nothing if @attr is
122  * null. Bool pointed to by @mod is set to true if this function changed the
123  * logical value of *dst, otherwise it is left as is.
124  */
125 static inline void ethnl_update_bool32(u32 *dst, const struct nlattr *attr,
126 				       bool *mod)
127 {
128 	u8 val;
129 
130 	if (!attr)
131 		return;
132 	val = !!nla_get_u8(attr);
133 	if (!!*dst == val)
134 		return;
135 
136 	*dst = val;
137 	*mod = true;
138 }
139 
140 /**
141  * ethnl_update_binary() - update binary data from NLA_BINARY atribute
142  * @dst:  value to update
143  * @len:  destination buffer length
144  * @attr: netlink attribute with new value or null
145  * @mod:  pointer to bool for modification tracking
146  *
147  * Use the u8 value from NLA_U8 netlink attribute @attr to rewrite data block
148  * of length @len at @dst by attribute payload; do nothing if @attr is null.
149  * Bool pointed to by @mod is set to true if this function changed the logical
150  * value of *dst, otherwise it is left as is.
151  */
152 static inline void ethnl_update_binary(void *dst, unsigned int len,
153 				       const struct nlattr *attr, bool *mod)
154 {
155 	if (!attr)
156 		return;
157 	if (nla_len(attr) < len)
158 		len = nla_len(attr);
159 	if (!memcmp(dst, nla_data(attr), len))
160 		return;
161 
162 	memcpy(dst, nla_data(attr), len);
163 	*mod = true;
164 }
165 
166 /**
167  * ethnl_update_bitfield32() - update u32 value from NLA_BITFIELD32 attribute
168  * @dst:  value to update
169  * @attr: netlink attribute with new value or null
170  * @mod:  pointer to bool for modification tracking
171  *
172  * Update bits in u32 value which are set in attribute's mask to values from
173  * attribute's value. Do nothing if @attr is null or the value wouldn't change;
174  * otherwise, set bool pointed to by @mod to true.
175  */
176 static inline void ethnl_update_bitfield32(u32 *dst, const struct nlattr *attr,
177 					   bool *mod)
178 {
179 	struct nla_bitfield32 change;
180 	u32 newval;
181 
182 	if (!attr)
183 		return;
184 	change = nla_get_bitfield32(attr);
185 	newval = (*dst & ~change.selector) | (change.value & change.selector);
186 	if (*dst == newval)
187 		return;
188 
189 	*dst = newval;
190 	*mod = true;
191 }
192 
193 /**
194  * ethnl_reply_header_size() - total size of reply header
195  *
196  * This is an upper estimate so that we do not need to hold RTNL lock longer
197  * than necessary (to prevent rename between size estimate and composing the
198  * message). Accounts only for device ifindex and name as those are the only
199  * attributes ethnl_fill_reply_header() puts into the reply header.
200  */
201 static inline unsigned int ethnl_reply_header_size(void)
202 {
203 	return nla_total_size(nla_total_size(sizeof(u32)) +
204 			      nla_total_size(IFNAMSIZ));
205 }
206 
207 /* GET request handling */
208 
209 /* Unified processing of GET requests uses two data structures: request info
210  * and reply data. Request info holds information parsed from client request
211  * and its stays constant through all request processing. Reply data holds data
212  * retrieved from ethtool_ops callbacks or other internal sources which is used
213  * to compose the reply. When processing a dump request, request info is filled
214  * only once (when the request message is parsed) but reply data is filled for
215  * each reply message.
216  *
217  * Both structures consist of part common for all request types (struct
218  * ethnl_req_info and struct ethnl_reply_data defined below) and optional
219  * parts specific for each request type. Common part always starts at offset 0.
220  */
221 
222 /**
223  * struct ethnl_req_info - base type of request information for GET requests
224  * @dev:   network device the request is for (may be null)
225  * @flags: request flags common for all request types
226  *
227  * This is a common base for request specific structures holding data from
228  * parsed userspace request. These always embed struct ethnl_req_info at
229  * zero offset.
230  */
231 struct ethnl_req_info {
232 	struct net_device	*dev;
233 	u32			flags;
234 };
235 
236 /**
237  * struct ethnl_reply_data - base type of reply data for GET requests
238  * @dev:       device for current reply message; in single shot requests it is
239  *             equal to &ethnl_req_info.dev; in dumps it's different for each
240  *             reply message
241  *
242  * This is a common base for request specific structures holding data for
243  * kernel reply message. These always embed struct ethnl_reply_data at zero
244  * offset.
245  */
246 struct ethnl_reply_data {
247 	struct net_device		*dev;
248 };
249 
250 static inline int ethnl_ops_begin(struct net_device *dev)
251 {
252 	if (dev && dev->ethtool_ops->begin)
253 		return dev->ethtool_ops->begin(dev);
254 	else
255 		return 0;
256 }
257 
258 static inline void ethnl_ops_complete(struct net_device *dev)
259 {
260 	if (dev && dev->ethtool_ops->complete)
261 		dev->ethtool_ops->complete(dev);
262 }
263 
264 /**
265  * struct ethnl_request_ops - unified handling of GET requests
266  * @request_cmd:      command id for request (GET)
267  * @reply_cmd:        command id for reply (GET_REPLY)
268  * @hdr_attr:         attribute type for request header
269  * @max_attr:         maximum (top level) attribute type
270  * @req_info_size:    size of request info
271  * @reply_data_size:  size of reply data
272  * @request_policy:   netlink policy for message contents
273  * @allow_nodev_do:   allow non-dump request with no device identification
274  * @parse_request:
275  *	Parse request except common header (struct ethnl_req_info). Common
276  *	header is already filled on entry, the rest up to @repdata_offset
277  *	is zero initialized. This callback should only modify type specific
278  *	request info by parsed attributes from request message.
279  * @prepare_data:
280  *	Retrieve and prepare data needed to compose a reply message. Calls to
281  *	ethtool_ops handlers are limited to this callback. Common reply data
282  *	(struct ethnl_reply_data) is filled on entry, type specific part after
283  *	it is zero initialized. This callback should only modify the type
284  *	specific part of reply data. Device identification from struct
285  *	ethnl_reply_data is to be used as for dump requests, it iterates
286  *	through network devices while dev member of struct ethnl_req_info
287  *	points to the device from client request.
288  * @reply_size:
289  *	Estimate reply message size. Returned value must be sufficient for
290  *	message payload without common reply header. The callback may returned
291  *	estimate higher than actual message size if exact calculation would
292  *	not be worth the saved memory space.
293  * @fill_reply:
294  *	Fill reply message payload (except for common header) from reply data.
295  *	The callback must not generate more payload than previously called
296  *	->reply_size() estimated.
297  * @cleanup_data:
298  *	Optional cleanup called when reply data is no longer needed. Can be
299  *	used e.g. to free any additional data structures outside the main
300  *	structure which were allocated by ->prepare_data(). When processing
301  *	dump requests, ->cleanup() is called for each message.
302  *
303  * Description of variable parts of GET request handling when using the
304  * unified infrastructure. When used, a pointer to an instance of this
305  * structure is to be added to &ethnl_default_requests array and generic
306  * handlers ethnl_default_doit(), ethnl_default_dumpit(),
307  * ethnl_default_start() and ethnl_default_done() used in @ethtool_genl_ops;
308  * ethnl_default_notify() can be used in @ethnl_notify_handlers to send
309  * notifications of the corresponding type.
310  */
311 struct ethnl_request_ops {
312 	u8			request_cmd;
313 	u8			reply_cmd;
314 	u16			hdr_attr;
315 	unsigned int		max_attr;
316 	unsigned int		req_info_size;
317 	unsigned int		reply_data_size;
318 	const struct nla_policy *request_policy;
319 	bool			allow_nodev_do;
320 
321 	int (*parse_request)(struct ethnl_req_info *req_info,
322 			     struct nlattr **tb,
323 			     struct netlink_ext_ack *extack);
324 	int (*prepare_data)(const struct ethnl_req_info *req_info,
325 			    struct ethnl_reply_data *reply_data,
326 			    struct genl_info *info);
327 	int (*reply_size)(const struct ethnl_req_info *req_info,
328 			  const struct ethnl_reply_data *reply_data);
329 	int (*fill_reply)(struct sk_buff *skb,
330 			  const struct ethnl_req_info *req_info,
331 			  const struct ethnl_reply_data *reply_data);
332 	void (*cleanup_data)(struct ethnl_reply_data *reply_data);
333 };
334 
335 /* request handlers */
336 
337 extern const struct ethnl_request_ops ethnl_strset_request_ops;
338 extern const struct ethnl_request_ops ethnl_linkinfo_request_ops;
339 extern const struct ethnl_request_ops ethnl_linkmodes_request_ops;
340 extern const struct ethnl_request_ops ethnl_linkstate_request_ops;
341 extern const struct ethnl_request_ops ethnl_debug_request_ops;
342 extern const struct ethnl_request_ops ethnl_wol_request_ops;
343 extern const struct ethnl_request_ops ethnl_features_request_ops;
344 extern const struct ethnl_request_ops ethnl_privflags_request_ops;
345 extern const struct ethnl_request_ops ethnl_rings_request_ops;
346 extern const struct ethnl_request_ops ethnl_channels_request_ops;
347 extern const struct ethnl_request_ops ethnl_coalesce_request_ops;
348 extern const struct ethnl_request_ops ethnl_pause_request_ops;
349 extern const struct ethnl_request_ops ethnl_eee_request_ops;
350 extern const struct ethnl_request_ops ethnl_tsinfo_request_ops;
351 
352 int ethnl_set_linkinfo(struct sk_buff *skb, struct genl_info *info);
353 int ethnl_set_linkmodes(struct sk_buff *skb, struct genl_info *info);
354 int ethnl_set_debug(struct sk_buff *skb, struct genl_info *info);
355 int ethnl_set_wol(struct sk_buff *skb, struct genl_info *info);
356 int ethnl_set_features(struct sk_buff *skb, struct genl_info *info);
357 int ethnl_set_privflags(struct sk_buff *skb, struct genl_info *info);
358 int ethnl_set_rings(struct sk_buff *skb, struct genl_info *info);
359 int ethnl_set_channels(struct sk_buff *skb, struct genl_info *info);
360 int ethnl_set_coalesce(struct sk_buff *skb, struct genl_info *info);
361 int ethnl_set_pause(struct sk_buff *skb, struct genl_info *info);
362 int ethnl_set_eee(struct sk_buff *skb, struct genl_info *info);
363 int ethnl_act_cable_test(struct sk_buff *skb, struct genl_info *info);
364 int ethnl_act_cable_test_tdr(struct sk_buff *skb, struct genl_info *info);
365 int ethnl_tunnel_info_doit(struct sk_buff *skb, struct genl_info *info);
366 int ethnl_tunnel_info_start(struct netlink_callback *cb);
367 int ethnl_tunnel_info_dumpit(struct sk_buff *skb, struct netlink_callback *cb);
368 
369 #endif /* _NET_ETHTOOL_NETLINK_H */
370