xref: /linux/net/sched/act_skbedit.c (revision 56d06fa29edd58c448766014afd833b7ff51247b)
1 /*
2  * Copyright (c) 2008, Intel Corporation.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms and conditions of the GNU General Public License,
6  * version 2, as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  *
13  * You should have received a copy of the GNU General Public License along with
14  * this program; if not, see <http://www.gnu.org/licenses/>.
15  *
16  * Author: Alexander Duyck <alexander.h.duyck@intel.com>
17  */
18 
19 #include <linux/module.h>
20 #include <linux/init.h>
21 #include <linux/kernel.h>
22 #include <linux/skbuff.h>
23 #include <linux/rtnetlink.h>
24 #include <net/netlink.h>
25 #include <net/pkt_sched.h>
26 
27 #include <linux/tc_act/tc_skbedit.h>
28 #include <net/tc_act/tc_skbedit.h>
29 
30 #define SKBEDIT_TAB_MASK     15
31 
32 static int skbedit_net_id;
33 
34 static int tcf_skbedit(struct sk_buff *skb, const struct tc_action *a,
35 		       struct tcf_result *res)
36 {
37 	struct tcf_skbedit *d = a->priv;
38 
39 	spin_lock(&d->tcf_lock);
40 	d->tcf_tm.lastuse = jiffies;
41 	bstats_update(&d->tcf_bstats, skb);
42 
43 	if (d->flags & SKBEDIT_F_PRIORITY)
44 		skb->priority = d->priority;
45 	if (d->flags & SKBEDIT_F_QUEUE_MAPPING &&
46 	    skb->dev->real_num_tx_queues > d->queue_mapping)
47 		skb_set_queue_mapping(skb, d->queue_mapping);
48 	if (d->flags & SKBEDIT_F_MARK)
49 		skb->mark = d->mark;
50 
51 	spin_unlock(&d->tcf_lock);
52 	return d->tcf_action;
53 }
54 
55 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
56 	[TCA_SKBEDIT_PARMS]		= { .len = sizeof(struct tc_skbedit) },
57 	[TCA_SKBEDIT_PRIORITY]		= { .len = sizeof(u32) },
58 	[TCA_SKBEDIT_QUEUE_MAPPING]	= { .len = sizeof(u16) },
59 	[TCA_SKBEDIT_MARK]		= { .len = sizeof(u32) },
60 };
61 
62 static int tcf_skbedit_init(struct net *net, struct nlattr *nla,
63 			    struct nlattr *est, struct tc_action *a,
64 			    int ovr, int bind)
65 {
66 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
67 	struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
68 	struct tc_skbedit *parm;
69 	struct tcf_skbedit *d;
70 	u32 flags = 0, *priority = NULL, *mark = NULL;
71 	u16 *queue_mapping = NULL;
72 	int ret = 0, err;
73 
74 	if (nla == NULL)
75 		return -EINVAL;
76 
77 	err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy);
78 	if (err < 0)
79 		return err;
80 
81 	if (tb[TCA_SKBEDIT_PARMS] == NULL)
82 		return -EINVAL;
83 
84 	if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
85 		flags |= SKBEDIT_F_PRIORITY;
86 		priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
87 	}
88 
89 	if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
90 		flags |= SKBEDIT_F_QUEUE_MAPPING;
91 		queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
92 	}
93 
94 	if (tb[TCA_SKBEDIT_MARK] != NULL) {
95 		flags |= SKBEDIT_F_MARK;
96 		mark = nla_data(tb[TCA_SKBEDIT_MARK]);
97 	}
98 
99 	if (!flags)
100 		return -EINVAL;
101 
102 	parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
103 
104 	if (!tcf_hash_check(tn, parm->index, a, bind)) {
105 		ret = tcf_hash_create(tn, parm->index, est, a,
106 				      sizeof(*d), bind, false);
107 		if (ret)
108 			return ret;
109 
110 		d = to_skbedit(a);
111 		ret = ACT_P_CREATED;
112 	} else {
113 		d = to_skbedit(a);
114 		if (bind)
115 			return 0;
116 		tcf_hash_release(a, bind);
117 		if (!ovr)
118 			return -EEXIST;
119 	}
120 
121 	spin_lock_bh(&d->tcf_lock);
122 
123 	d->flags = flags;
124 	if (flags & SKBEDIT_F_PRIORITY)
125 		d->priority = *priority;
126 	if (flags & SKBEDIT_F_QUEUE_MAPPING)
127 		d->queue_mapping = *queue_mapping;
128 	if (flags & SKBEDIT_F_MARK)
129 		d->mark = *mark;
130 
131 	d->tcf_action = parm->action;
132 
133 	spin_unlock_bh(&d->tcf_lock);
134 
135 	if (ret == ACT_P_CREATED)
136 		tcf_hash_insert(tn, a);
137 	return ret;
138 }
139 
140 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
141 			    int bind, int ref)
142 {
143 	unsigned char *b = skb_tail_pointer(skb);
144 	struct tcf_skbedit *d = a->priv;
145 	struct tc_skbedit opt = {
146 		.index   = d->tcf_index,
147 		.refcnt  = d->tcf_refcnt - ref,
148 		.bindcnt = d->tcf_bindcnt - bind,
149 		.action  = d->tcf_action,
150 	};
151 	struct tcf_t t;
152 
153 	if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
154 		goto nla_put_failure;
155 	if ((d->flags & SKBEDIT_F_PRIORITY) &&
156 	    nla_put(skb, TCA_SKBEDIT_PRIORITY, sizeof(d->priority),
157 		    &d->priority))
158 		goto nla_put_failure;
159 	if ((d->flags & SKBEDIT_F_QUEUE_MAPPING) &&
160 	    nla_put(skb, TCA_SKBEDIT_QUEUE_MAPPING,
161 		    sizeof(d->queue_mapping), &d->queue_mapping))
162 		goto nla_put_failure;
163 	if ((d->flags & SKBEDIT_F_MARK) &&
164 	    nla_put(skb, TCA_SKBEDIT_MARK, sizeof(d->mark),
165 		    &d->mark))
166 		goto nla_put_failure;
167 	t.install = jiffies_to_clock_t(jiffies - d->tcf_tm.install);
168 	t.lastuse = jiffies_to_clock_t(jiffies - d->tcf_tm.lastuse);
169 	t.expires = jiffies_to_clock_t(d->tcf_tm.expires);
170 	if (nla_put(skb, TCA_SKBEDIT_TM, sizeof(t), &t))
171 		goto nla_put_failure;
172 	return skb->len;
173 
174 nla_put_failure:
175 	nlmsg_trim(skb, b);
176 	return -1;
177 }
178 
179 static int tcf_skbedit_walker(struct net *net, struct sk_buff *skb,
180 			      struct netlink_callback *cb, int type,
181 			      struct tc_action *a)
182 {
183 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
184 
185 	return tcf_generic_walker(tn, skb, cb, type, a);
186 }
187 
188 static int tcf_skbedit_search(struct net *net, struct tc_action *a, u32 index)
189 {
190 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
191 
192 	return tcf_hash_search(tn, a, index);
193 }
194 
195 static struct tc_action_ops act_skbedit_ops = {
196 	.kind		=	"skbedit",
197 	.type		=	TCA_ACT_SKBEDIT,
198 	.owner		=	THIS_MODULE,
199 	.act		=	tcf_skbedit,
200 	.dump		=	tcf_skbedit_dump,
201 	.init		=	tcf_skbedit_init,
202 	.walk		=	tcf_skbedit_walker,
203 	.lookup		=	tcf_skbedit_search,
204 };
205 
206 static __net_init int skbedit_init_net(struct net *net)
207 {
208 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
209 
210 	return tc_action_net_init(tn, &act_skbedit_ops, SKBEDIT_TAB_MASK);
211 }
212 
213 static void __net_exit skbedit_exit_net(struct net *net)
214 {
215 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
216 
217 	tc_action_net_exit(tn);
218 }
219 
220 static struct pernet_operations skbedit_net_ops = {
221 	.init = skbedit_init_net,
222 	.exit = skbedit_exit_net,
223 	.id   = &skbedit_net_id,
224 	.size = sizeof(struct tc_action_net),
225 };
226 
227 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
228 MODULE_DESCRIPTION("SKB Editing");
229 MODULE_LICENSE("GPL");
230 
231 static int __init skbedit_init_module(void)
232 {
233 	return tcf_register_action(&act_skbedit_ops, &skbedit_net_ops);
234 }
235 
236 static void __exit skbedit_cleanup_module(void)
237 {
238 	tcf_unregister_action(&act_skbedit_ops, &skbedit_net_ops);
239 }
240 
241 module_init(skbedit_init_module);
242 module_exit(skbedit_cleanup_module);
243