xref: /linux/net/ethtool/privflags.c (revision d195c39052d1da278a00a6744ce59c383b67b191)
1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 #include "netlink.h"
4 #include "common.h"
5 #include "bitset.h"
6 
7 struct privflags_req_info {
8 	struct ethnl_req_info		base;
9 };
10 
11 struct privflags_reply_data {
12 	struct ethnl_reply_data		base;
13 	const char			(*priv_flag_names)[ETH_GSTRING_LEN];
14 	unsigned int			n_priv_flags;
15 	u32				priv_flags;
16 };
17 
18 #define PRIVFLAGS_REPDATA(__reply_base) \
19 	container_of(__reply_base, struct privflags_reply_data, base)
20 
21 static const struct nla_policy
22 privflags_get_policy[ETHTOOL_A_PRIVFLAGS_MAX + 1] = {
23 	[ETHTOOL_A_PRIVFLAGS_UNSPEC]		= { .type = NLA_REJECT },
24 	[ETHTOOL_A_PRIVFLAGS_HEADER]		= { .type = NLA_NESTED },
25 	[ETHTOOL_A_PRIVFLAGS_FLAGS]		= { .type = NLA_REJECT },
26 };
27 
28 static int ethnl_get_priv_flags_info(struct net_device *dev,
29 				     unsigned int *count,
30 				     const char (**names)[ETH_GSTRING_LEN])
31 {
32 	const struct ethtool_ops *ops = dev->ethtool_ops;
33 	int nflags;
34 
35 	nflags = ops->get_sset_count(dev, ETH_SS_PRIV_FLAGS);
36 	if (nflags < 0)
37 		return nflags;
38 
39 	if (names) {
40 		*names = kcalloc(nflags, ETH_GSTRING_LEN, GFP_KERNEL);
41 		if (!*names)
42 			return -ENOMEM;
43 		ops->get_strings(dev, ETH_SS_PRIV_FLAGS, (u8 *)*names);
44 	}
45 
46 	/* We can pass more than 32 private flags to userspace via netlink but
47 	 * we cannot get more with ethtool_ops::get_priv_flags(). Note that we
48 	 * must not adjust nflags before allocating the space for flag names
49 	 * as the buffer must be large enough for all flags.
50 	 */
51 	if (WARN_ONCE(nflags > 32,
52 		      "device %s reports more than 32 private flags (%d)\n",
53 		      netdev_name(dev), nflags))
54 		nflags = 32;
55 	*count = nflags;
56 
57 	return 0;
58 }
59 
60 static int privflags_prepare_data(const struct ethnl_req_info *req_base,
61 				  struct ethnl_reply_data *reply_base,
62 				  struct genl_info *info)
63 {
64 	struct privflags_reply_data *data = PRIVFLAGS_REPDATA(reply_base);
65 	struct net_device *dev = reply_base->dev;
66 	const char (*names)[ETH_GSTRING_LEN];
67 	const struct ethtool_ops *ops;
68 	unsigned int nflags;
69 	int ret;
70 
71 	ops = dev->ethtool_ops;
72 	if (!ops->get_priv_flags || !ops->get_sset_count || !ops->get_strings)
73 		return -EOPNOTSUPP;
74 	ret = ethnl_ops_begin(dev);
75 	if (ret < 0)
76 		return ret;
77 
78 	ret = ethnl_get_priv_flags_info(dev, &nflags, &names);
79 	if (ret < 0)
80 		goto out_ops;
81 	data->priv_flags = ops->get_priv_flags(dev);
82 	data->priv_flag_names = names;
83 	data->n_priv_flags = nflags;
84 
85 out_ops:
86 	ethnl_ops_complete(dev);
87 	return ret;
88 }
89 
90 static int privflags_reply_size(const struct ethnl_req_info *req_base,
91 				const struct ethnl_reply_data *reply_base)
92 {
93 	const struct privflags_reply_data *data = PRIVFLAGS_REPDATA(reply_base);
94 	bool compact = req_base->flags & ETHTOOL_FLAG_COMPACT_BITSETS;
95 	const u32 all_flags = ~(u32)0 >> (32 - data->n_priv_flags);
96 
97 	return ethnl_bitset32_size(&data->priv_flags, &all_flags,
98 				   data->n_priv_flags,
99 				   data->priv_flag_names, compact);
100 }
101 
102 static int privflags_fill_reply(struct sk_buff *skb,
103 				const struct ethnl_req_info *req_base,
104 				const struct ethnl_reply_data *reply_base)
105 {
106 	const struct privflags_reply_data *data = PRIVFLAGS_REPDATA(reply_base);
107 	bool compact = req_base->flags & ETHTOOL_FLAG_COMPACT_BITSETS;
108 	const u32 all_flags = ~(u32)0 >> (32 - data->n_priv_flags);
109 
110 	return ethnl_put_bitset32(skb, ETHTOOL_A_PRIVFLAGS_FLAGS,
111 				  &data->priv_flags, &all_flags,
112 				  data->n_priv_flags, data->priv_flag_names,
113 				  compact);
114 }
115 
116 static void privflags_cleanup_data(struct ethnl_reply_data *reply_data)
117 {
118 	struct privflags_reply_data *data = PRIVFLAGS_REPDATA(reply_data);
119 
120 	kfree(data->priv_flag_names);
121 }
122 
123 const struct ethnl_request_ops ethnl_privflags_request_ops = {
124 	.request_cmd		= ETHTOOL_MSG_PRIVFLAGS_GET,
125 	.reply_cmd		= ETHTOOL_MSG_PRIVFLAGS_GET_REPLY,
126 	.hdr_attr		= ETHTOOL_A_PRIVFLAGS_HEADER,
127 	.max_attr		= ETHTOOL_A_PRIVFLAGS_MAX,
128 	.req_info_size		= sizeof(struct privflags_req_info),
129 	.reply_data_size	= sizeof(struct privflags_reply_data),
130 	.request_policy		= privflags_get_policy,
131 
132 	.prepare_data		= privflags_prepare_data,
133 	.reply_size		= privflags_reply_size,
134 	.fill_reply		= privflags_fill_reply,
135 	.cleanup_data		= privflags_cleanup_data,
136 };
137 
138 /* PRIVFLAGS_SET */
139 
140 static const struct nla_policy
141 privflags_set_policy[ETHTOOL_A_PRIVFLAGS_MAX + 1] = {
142 	[ETHTOOL_A_PRIVFLAGS_UNSPEC]		= { .type = NLA_REJECT },
143 	[ETHTOOL_A_PRIVFLAGS_HEADER]		= { .type = NLA_NESTED },
144 	[ETHTOOL_A_PRIVFLAGS_FLAGS]		= { .type = NLA_NESTED },
145 };
146 
147 int ethnl_set_privflags(struct sk_buff *skb, struct genl_info *info)
148 {
149 	struct nlattr *tb[ETHTOOL_A_PRIVFLAGS_MAX + 1];
150 	const char (*names)[ETH_GSTRING_LEN] = NULL;
151 	struct ethnl_req_info req_info = {};
152 	const struct ethtool_ops *ops;
153 	struct net_device *dev;
154 	unsigned int nflags;
155 	bool mod = false;
156 	bool compact;
157 	u32 flags;
158 	int ret;
159 
160 	ret = nlmsg_parse(info->nlhdr, GENL_HDRLEN, tb,
161 			  ETHTOOL_A_PRIVFLAGS_MAX, privflags_set_policy,
162 			  info->extack);
163 	if (ret < 0)
164 		return ret;
165 	if (!tb[ETHTOOL_A_PRIVFLAGS_FLAGS])
166 		return -EINVAL;
167 	ret = ethnl_bitset_is_compact(tb[ETHTOOL_A_PRIVFLAGS_FLAGS], &compact);
168 	if (ret < 0)
169 		return ret;
170 	ret = ethnl_parse_header_dev_get(&req_info,
171 					 tb[ETHTOOL_A_PRIVFLAGS_HEADER],
172 					 genl_info_net(info), info->extack,
173 					 true);
174 	if (ret < 0)
175 		return ret;
176 	dev = req_info.dev;
177 	ops = dev->ethtool_ops;
178 	ret = -EOPNOTSUPP;
179 	if (!ops->get_priv_flags || !ops->set_priv_flags ||
180 	    !ops->get_sset_count || !ops->get_strings)
181 		goto out_dev;
182 
183 	rtnl_lock();
184 	ret = ethnl_ops_begin(dev);
185 	if (ret < 0)
186 		goto out_rtnl;
187 	ret = ethnl_get_priv_flags_info(dev, &nflags, compact ? NULL : &names);
188 	if (ret < 0)
189 		goto out_ops;
190 	flags = ops->get_priv_flags(dev);
191 
192 	ret = ethnl_update_bitset32(&flags, nflags,
193 				    tb[ETHTOOL_A_PRIVFLAGS_FLAGS], names,
194 				    info->extack, &mod);
195 	if (ret < 0 || !mod)
196 		goto out_free;
197 	ret = ops->set_priv_flags(dev, flags);
198 	if (ret < 0)
199 		goto out_free;
200 	ethtool_notify(dev, ETHTOOL_MSG_PRIVFLAGS_NTF, NULL);
201 
202 out_free:
203 	kfree(names);
204 out_ops:
205 	ethnl_ops_complete(dev);
206 out_rtnl:
207 	rtnl_unlock();
208 out_dev:
209 	dev_put(dev);
210 	return ret;
211 }
212