xref: /linux/net/sched/act_skbedit.c (revision a3b072cd180c12e8fe0ece9487b9065808327640)
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 static struct tcf_hashinfo skbedit_hash_info;
32 
33 static int tcf_skbedit(struct sk_buff *skb, const struct tc_action *a,
34 		       struct tcf_result *res)
35 {
36 	struct tcf_skbedit *d = a->priv;
37 
38 	spin_lock(&d->tcf_lock);
39 	d->tcf_tm.lastuse = jiffies;
40 	bstats_update(&d->tcf_bstats, skb);
41 
42 	if (d->flags & SKBEDIT_F_PRIORITY)
43 		skb->priority = d->priority;
44 	if (d->flags & SKBEDIT_F_QUEUE_MAPPING &&
45 	    skb->dev->real_num_tx_queues > d->queue_mapping)
46 		skb_set_queue_mapping(skb, d->queue_mapping);
47 	if (d->flags & SKBEDIT_F_MARK)
48 		skb->mark = d->mark;
49 
50 	spin_unlock(&d->tcf_lock);
51 	return d->tcf_action;
52 }
53 
54 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
55 	[TCA_SKBEDIT_PARMS]		= { .len = sizeof(struct tc_skbedit) },
56 	[TCA_SKBEDIT_PRIORITY]		= { .len = sizeof(u32) },
57 	[TCA_SKBEDIT_QUEUE_MAPPING]	= { .len = sizeof(u16) },
58 	[TCA_SKBEDIT_MARK]		= { .len = sizeof(u32) },
59 };
60 
61 static int tcf_skbedit_init(struct net *net, struct nlattr *nla,
62 			    struct nlattr *est, struct tc_action *a,
63 			    int ovr, int bind)
64 {
65 	struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
66 	struct tc_skbedit *parm;
67 	struct tcf_skbedit *d;
68 	struct tcf_common *pc;
69 	u32 flags = 0, *priority = NULL, *mark = NULL;
70 	u16 *queue_mapping = NULL;
71 	int ret = 0, err;
72 
73 	if (nla == NULL)
74 		return -EINVAL;
75 
76 	err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy);
77 	if (err < 0)
78 		return err;
79 
80 	if (tb[TCA_SKBEDIT_PARMS] == NULL)
81 		return -EINVAL;
82 
83 	if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
84 		flags |= SKBEDIT_F_PRIORITY;
85 		priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
86 	}
87 
88 	if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
89 		flags |= SKBEDIT_F_QUEUE_MAPPING;
90 		queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
91 	}
92 
93 	if (tb[TCA_SKBEDIT_MARK] != NULL) {
94 		flags |= SKBEDIT_F_MARK;
95 		mark = nla_data(tb[TCA_SKBEDIT_MARK]);
96 	}
97 
98 	if (!flags)
99 		return -EINVAL;
100 
101 	parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
102 
103 	pc = tcf_hash_check(parm->index, a, bind);
104 	if (!pc) {
105 		pc = tcf_hash_create(parm->index, est, a, sizeof(*d), bind);
106 		if (IS_ERR(pc))
107 			return PTR_ERR(pc);
108 
109 		d = to_skbedit(pc);
110 		ret = ACT_P_CREATED;
111 	} else {
112 		d = to_skbedit(pc);
113 		if (bind)
114 			return 0;
115 		tcf_hash_release(pc, bind, a->ops->hinfo);
116 		if (!ovr)
117 			return -EEXIST;
118 	}
119 
120 	spin_lock_bh(&d->tcf_lock);
121 
122 	d->flags = flags;
123 	if (flags & SKBEDIT_F_PRIORITY)
124 		d->priority = *priority;
125 	if (flags & SKBEDIT_F_QUEUE_MAPPING)
126 		d->queue_mapping = *queue_mapping;
127 	if (flags & SKBEDIT_F_MARK)
128 		d->mark = *mark;
129 
130 	d->tcf_action = parm->action;
131 
132 	spin_unlock_bh(&d->tcf_lock);
133 
134 	if (ret == ACT_P_CREATED)
135 		tcf_hash_insert(pc, a->ops->hinfo);
136 	return ret;
137 }
138 
139 static int tcf_skbedit_cleanup(struct tc_action *a, int bind)
140 {
141 	struct tcf_skbedit *d = a->priv;
142 
143 	if (d)
144 		return tcf_hash_release(&d->common, bind, &skbedit_hash_info);
145 	return 0;
146 }
147 
148 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
149 			    int bind, int ref)
150 {
151 	unsigned char *b = skb_tail_pointer(skb);
152 	struct tcf_skbedit *d = a->priv;
153 	struct tc_skbedit opt = {
154 		.index   = d->tcf_index,
155 		.refcnt  = d->tcf_refcnt - ref,
156 		.bindcnt = d->tcf_bindcnt - bind,
157 		.action  = d->tcf_action,
158 	};
159 	struct tcf_t t;
160 
161 	if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
162 		goto nla_put_failure;
163 	if ((d->flags & SKBEDIT_F_PRIORITY) &&
164 	    nla_put(skb, TCA_SKBEDIT_PRIORITY, sizeof(d->priority),
165 		    &d->priority))
166 		goto nla_put_failure;
167 	if ((d->flags & SKBEDIT_F_QUEUE_MAPPING) &&
168 	    nla_put(skb, TCA_SKBEDIT_QUEUE_MAPPING,
169 		    sizeof(d->queue_mapping), &d->queue_mapping))
170 		goto nla_put_failure;
171 	if ((d->flags & SKBEDIT_F_MARK) &&
172 	    nla_put(skb, TCA_SKBEDIT_MARK, sizeof(d->mark),
173 		    &d->mark))
174 		goto nla_put_failure;
175 	t.install = jiffies_to_clock_t(jiffies - d->tcf_tm.install);
176 	t.lastuse = jiffies_to_clock_t(jiffies - d->tcf_tm.lastuse);
177 	t.expires = jiffies_to_clock_t(d->tcf_tm.expires);
178 	if (nla_put(skb, TCA_SKBEDIT_TM, sizeof(t), &t))
179 		goto nla_put_failure;
180 	return skb->len;
181 
182 nla_put_failure:
183 	nlmsg_trim(skb, b);
184 	return -1;
185 }
186 
187 static struct tc_action_ops act_skbedit_ops = {
188 	.kind		=	"skbedit",
189 	.hinfo		=	&skbedit_hash_info,
190 	.type		=	TCA_ACT_SKBEDIT,
191 	.owner		=	THIS_MODULE,
192 	.act		=	tcf_skbedit,
193 	.dump		=	tcf_skbedit_dump,
194 	.cleanup	=	tcf_skbedit_cleanup,
195 	.init		=	tcf_skbedit_init,
196 };
197 
198 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
199 MODULE_DESCRIPTION("SKB Editing");
200 MODULE_LICENSE("GPL");
201 
202 static int __init skbedit_init_module(void)
203 {
204 	int err = tcf_hashinfo_init(&skbedit_hash_info, SKBEDIT_TAB_MASK);
205 	if (err)
206 		return err;
207 	return tcf_register_action(&act_skbedit_ops);
208 }
209 
210 static void __exit skbedit_cleanup_module(void)
211 {
212 	tcf_hashinfo_destroy(&skbedit_hash_info);
213 	tcf_unregister_action(&act_skbedit_ops);
214 }
215 
216 module_init(skbedit_init_module);
217 module_exit(skbedit_cleanup_module);
218