summaryrefslogtreecommitdiff
path: root/net/ethtool/netlink.h
blob: 49fee19bc6aa4340cab1989bf95c903cf51e4e52 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
/* SPDX-License-Identifier: GPL-2.0-only */

#ifndef _NET_ETHTOOL_NETLINK_H
#define _NET_ETHTOOL_NETLINK_H

#include <linux/ethtool_netlink.h>
#include <linux/netdevice.h>
#include <net/genetlink.h>
#include <net/sock.h>

struct ethnl_req_info;

int ethnl_parse_header_dev_get(struct ethnl_req_info *req_info,
			       const struct nlattr *nest, struct net *net,
			       struct netlink_ext_ack *extack,
			       bool require_dev);
int ethnl_fill_reply_header(struct sk_buff *skb, struct net_device *dev,
			    u16 attrtype);
struct sk_buff *ethnl_reply_init(size_t payload, struct net_device *dev, u8 cmd,
				 u16 hdr_attrtype, struct genl_info *info,
				 void **ehdrp);

/**
 * ethnl_strz_size() - calculate attribute length for fixed size string
 * @s: ETH_GSTRING_LEN sized string (may not be null terminated)
 *
 * Return: total length of an attribute with null terminated string from @s
 */
static inline int ethnl_strz_size(const char *s)
{
	return nla_total_size(strnlen(s, ETH_GSTRING_LEN) + 1);
}

/**
 * ethnl_put_strz() - put string attribute with fixed size string
 * @skb:     skb with the message
 * @attrype: attribute type
 * @s:       ETH_GSTRING_LEN sized string (may not be null terminated)
 *
 * Puts an attribute with null terminated string from @s into the message.
 *
 * Return: 0 on success, negative error code on failure
 */
static inline int ethnl_put_strz(struct sk_buff *skb, u16 attrtype,
				 const char *s)
{
	unsigned int len = strnlen(s, ETH_GSTRING_LEN);
	struct nlattr *attr;

	attr = nla_reserve(skb, attrtype, len + 1);
	if (!attr)
		return -EMSGSIZE;

	memcpy(nla_data(attr), s, len);
	((char *)nla_data(attr))[len] = '\0';
	return 0;
}

/**
 * ethnl_update_u32() - update u32 value from NLA_U32 attribute
 * @dst:  value to update
 * @attr: netlink attribute with new value or null
 * @mod:  pointer to bool for modification tracking
 *
 * Copy the u32 value from NLA_U32 netlink attribute @attr into variable
 * pointed to by @dst; do nothing if @attr is null. Bool pointed to by @mod
 * is set to true if this function changed the value of *dst, otherwise it
 * is left as is.
 */
static inline void ethnl_update_u32(u32 *dst, const struct nlattr *attr,
				    bool *mod)
{
	u32 val;

	if (!attr)
		return;
	val = nla_get_u32(attr);
	if (*dst == val)
		return;

	*dst = val;
	*mod = true;
}

/**
 * ethnl_update_u8() - update u8 value from NLA_U8 attribute
 * @dst:  value to update
 * @attr: netlink attribute with new value or null
 * @mod:  pointer to bool for modification tracking
 *
 * Copy the u8 value from NLA_U8 netlink attribute @attr into variable
 * pointed to by @dst; do nothing if @attr is null. Bool pointed to by @mod
 * is set to true if this function changed the value of *dst, otherwise it
 * is left as is.
 */
static inline void ethnl_update_u8(u8 *dst, const struct nlattr *attr,
				   bool *mod)
{
	u8 val;

	if (!attr)
		return;
	val = nla_get_u8(attr);
	if (*dst == val)
		return;

	*dst = val;
	*mod = true;
}

/**
 * ethnl_update_bool32() - update u32 used as bool from NLA_U8 attribute
 * @dst:  value to update
 * @attr: netlink attribute with new value or null
 * @mod:  pointer to bool for modification tracking
 *
 * Use the u8 value from NLA_U8 netlink attribute @attr to set u32 variable
 * pointed to by @dst to 0 (if zero) or 1 (if not); do nothing if @attr is
 * null. Bool pointed to by @mod is set to true if this function changed the
 * logical value of *dst, otherwise it is left as is.
 */
static inline void ethnl_update_bool32(u32 *dst, const struct nlattr *attr,
				       bool *mod)
{
	u8 val;

	if (!attr)
		return;
	val = !!nla_get_u8(attr);
	if (!!*dst == val)
		return;

	*dst = val;
	*mod = true;
}

/**
 * ethnl_update_binary() - update binary data from NLA_BINARY atribute
 * @dst:  value to update
 * @len:  destination buffer length
 * @attr: netlink attribute with new value or null
 * @mod:  pointer to bool for modification tracking
 *
 * Use the u8 value from NLA_U8 netlink attribute @attr to rewrite data block
 * of length @len at @dst by attribute payload; do nothing if @attr is null.
 * Bool pointed to by @mod is set to true if this function changed the logical
 * value of *dst, otherwise it is left as is.
 */
static inline void ethnl_update_binary(void *dst, unsigned int len,
				       const struct nlattr *attr, bool *mod)
{
	if (!attr)
		return;
	if (nla_len(attr) < len)
		len = nla_len(attr);
	if (!memcmp(dst, nla_data(attr), len))
		return;

	memcpy(dst, nla_data(attr), len);
	*mod = true;
}

/**
 * ethnl_update_bitfield32() - update u32 value from NLA_BITFIELD32 attribute
 * @dst:  value to update
 * @attr: netlink attribute with new value or null
 * @mod:  pointer to bool for modification tracking
 *
 * Update bits in u32 value which are set in attribute's mask to values from
 * attribute's value. Do nothing if @attr is null or the value wouldn't change;
 * otherwise, set bool pointed to by @mod to true.
 */
static inline void ethnl_update_bitfield32(u32 *dst, const struct nlattr *attr,
					   bool *mod)
{
	struct nla_bitfield32 change;
	u32 newval;

	if (!attr)
		return;
	change = nla_get_bitfield32(attr);
	newval = (*dst & ~change.selector) | (change.value & change.selector);
	if (*dst == newval)
		return;

	*dst = newval;
	*mod = true;
}

/**
 * ethnl_reply_header_size() - total size of reply header
 *
 * This is an upper estimate so that we do not need to hold RTNL lock longer
 * than necessary (to prevent rename between size estimate and composing the
 * message). Accounts only for device ifindex and name as those are the only
 * attributes ethnl_fill_reply_header() puts into the reply header.
 */
static inline unsigned int ethnl_reply_header_size(void)
{
	return nla_total_size(nla_total_size(sizeof(u32)) +
			      nla_total_size(IFNAMSIZ));
}

/* GET request handling */

/* Unified processing of GET requests uses two data structures: request info
 * and reply data. Request info holds information parsed from client request
 * and its stays constant through all request processing. Reply data holds data
 * retrieved from ethtool_ops callbacks or other internal sources which is used
 * to compose the reply. When processing a dump request, request info is filled
 * only once (when the request message is parsed) but reply data is filled for
 * each reply message.
 *
 * Both structures consist of part common for all request types (struct
 * ethnl_req_info and struct ethnl_reply_data defined below) and optional
 * parts specific for each request type. Common part always starts at offset 0.
 */

/**
 * struct ethnl_req_info - base type of request information for GET requests
 * @dev:   network device the request is for (may be null)
 * @flags: request flags common for all request types
 *
 * This is a common base for request specific structures holding data from
 * parsed userspace request. These always embed struct ethnl_req_info at
 * zero offset.
 */
struct ethnl_req_info {
	struct net_device	*dev;
	u32			flags;
};

/**
 * struct ethnl_reply_data - base type of reply data for GET requests
 * @dev:       device for current reply message; in single shot requests it is
 *             equal to &ethnl_req_info.dev; in dumps it's different for each
 *             reply message
 *
 * This is a common base for request specific structures holding data for
 * kernel reply message. These always embed struct ethnl_reply_data at zero
 * offset.
 */
struct ethnl_reply_data {
	struct net_device		*dev;
};

static inline int ethnl_ops_begin(struct net_device *dev)
{
	if (dev && dev->ethtool_ops->begin)
		return dev->ethtool_ops->begin(dev);
	else
		return 0;
}

static inline void ethnl_ops_complete(struct net_device *dev)
{
	if (dev && dev->ethtool_ops->complete)
		dev->ethtool_ops->complete(dev);
}

/**
 * struct ethnl_request_ops - unified handling of GET requests
 * @request_cmd:      command id for request (GET)
 * @reply_cmd:        command id for reply (GET_REPLY)
 * @hdr_attr:         attribute type for request header
 * @max_attr:         maximum (top level) attribute type
 * @req_info_size:    size of request info
 * @reply_data_size:  size of reply data
 * @request_policy:   netlink policy for message contents
 * @allow_nodev_do:   allow non-dump request with no device identification
 * @parse_request:
 *	Parse request except common header (struct ethnl_req_info). Common
 *	header is already filled on entry, the rest up to @repdata_offset
 *	is zero initialized. This callback should only modify type specific
 *	request info by parsed attributes from request message.
 * @prepare_data:
 *	Retrieve and prepare data needed to compose a reply message. Calls to
 *	ethtool_ops handlers are limited to this callback. Common reply data
 *	(struct ethnl_reply_data) is filled on entry, type specific part after
 *	it is zero initialized. This callback should only modify the type
 *	specific part of reply data. Device identification from struct
 *	ethnl_reply_data is to be used as for dump requests, it iterates
 *	through network devices while dev member of struct ethnl_req_info
 *	points to the device from client request.
 * @reply_size:
 *	Estimate reply message size. Returned value must be sufficient for
 *	message payload without common reply header. The callback may returned
 *	estimate higher than actual message size if exact calculation would
 *	not be worth the saved memory space.
 * @fill_reply:
 *	Fill reply message payload (except for common header) from reply data.
 *	The callback must not generate more payload than previously called
 *	->reply_size() estimated.
 * @cleanup_data:
 *	Optional cleanup called when reply data is no longer needed. Can be
 *	used e.g. to free any additional data structures outside the main
 *	structure which were allocated by ->prepare_data(). When processing
 *	dump requests, ->cleanup() is called for each message.
 *
 * Description of variable parts of GET request handling when using the
 * unified infrastructure. When used, a pointer to an instance of this
 * structure is to be added to &ethnl_default_requests array and generic
 * handlers ethnl_default_doit(), ethnl_default_dumpit(),
 * ethnl_default_start() and ethnl_default_done() used in @ethtool_genl_ops;
 * ethnl_default_notify() can be used in @ethnl_notify_handlers to send
 * notifications of the corresponding type.
 */
struct ethnl_request_ops {
	u8			request_cmd;
	u8			reply_cmd;
	u16			hdr_attr;
	unsigned int		max_attr;
	unsigned int		req_info_size;
	unsigned int		reply_data_size;
	const struct nla_policy *request_policy;
	bool			allow_nodev_do;

	int (*parse_request)(struct ethnl_req_info *req_info,
			     struct nlattr **tb,
			     struct netlink_ext_ack *extack);
	int (*prepare_data)(const struct ethnl_req_info *req_info,
			    struct ethnl_reply_data *reply_data,
			    struct genl_info *info);
	int (*reply_size)(const struct ethnl_req_info *req_info,
			  const struct ethnl_reply_data *reply_data);
	int (*fill_reply)(struct sk_buff *skb,
			  const struct ethnl_req_info *req_info,
			  const struct ethnl_reply_data *reply_data);
	void (*cleanup_data)(struct ethnl_reply_data *reply_data);
};

/* request handlers */

extern const struct ethnl_request_ops ethnl_strset_request_ops;
extern const struct ethnl_request_ops ethnl_linkinfo_request_ops;
extern const struct ethnl_request_ops ethnl_linkmodes_request_ops;
extern const struct ethnl_request_ops ethnl_linkstate_request_ops;
extern const struct ethnl_request_ops ethnl_debug_request_ops;
extern const struct ethnl_request_ops ethnl_wol_request_ops;
extern const struct ethnl_request_ops ethnl_features_request_ops;
extern const struct ethnl_request_ops ethnl_privflags_request_ops;
extern const struct ethnl_request_ops ethnl_rings_request_ops;
extern const struct ethnl_request_ops ethnl_channels_request_ops;
extern const struct ethnl_request_ops ethnl_coalesce_request_ops;
extern const struct ethnl_request_ops ethnl_pause_request_ops;

int ethnl_set_linkinfo(struct sk_buff *skb, struct genl_info *info);
int ethnl_set_linkmodes(struct sk_buff *skb, struct genl_info *info);
int ethnl_set_debug(struct sk_buff *skb, struct genl_info *info);
int ethnl_set_wol(struct sk_buff *skb, struct genl_info *info);
int ethnl_set_features(struct sk_buff *skb, struct genl_info *info);
int ethnl_set_privflags(struct sk_buff *skb, struct genl_info *info);
int ethnl_set_rings(struct sk_buff *skb, struct genl_info *info);
int ethnl_set_channels(struct sk_buff *skb, struct genl_info *info);
int ethnl_set_coalesce(struct sk_buff *skb, struct genl_info *info);
int ethnl_set_pause(struct sk_buff *skb, struct genl_info *info);

#endif /* _NET_ETHTOOL_NETLINK_H */