xref: /linux/net/sched/act_skbedit.c (revision 9e9f60108423f18a99c9cc93ef7f23490ecc709b)
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 tcf_skbedit(struct sk_buff *skb, const struct tc_action *a,
33 		       struct tcf_result *res)
34 {
35 	struct tcf_skbedit *d = a->priv;
36 
37 	spin_lock(&d->tcf_lock);
38 	d->tcf_tm.lastuse = jiffies;
39 	bstats_update(&d->tcf_bstats, skb);
40 
41 	if (d->flags & SKBEDIT_F_PRIORITY)
42 		skb->priority = d->priority;
43 	if (d->flags & SKBEDIT_F_QUEUE_MAPPING &&
44 	    skb->dev->real_num_tx_queues > d->queue_mapping)
45 		skb_set_queue_mapping(skb, d->queue_mapping);
46 	if (d->flags & SKBEDIT_F_MARK)
47 		skb->mark = d->mark;
48 
49 	spin_unlock(&d->tcf_lock);
50 	return d->tcf_action;
51 }
52 
53 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
54 	[TCA_SKBEDIT_PARMS]		= { .len = sizeof(struct tc_skbedit) },
55 	[TCA_SKBEDIT_PRIORITY]		= { .len = sizeof(u32) },
56 	[TCA_SKBEDIT_QUEUE_MAPPING]	= { .len = sizeof(u16) },
57 	[TCA_SKBEDIT_MARK]		= { .len = sizeof(u32) },
58 };
59 
60 static int tcf_skbedit_init(struct net *net, struct nlattr *nla,
61 			    struct nlattr *est, struct tc_action *a,
62 			    int ovr, int bind)
63 {
64 	struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
65 	struct tc_skbedit *parm;
66 	struct tcf_skbedit *d;
67 	u32 flags = 0, *priority = NULL, *mark = NULL;
68 	u16 *queue_mapping = NULL;
69 	int ret = 0, err;
70 
71 	if (nla == NULL)
72 		return -EINVAL;
73 
74 	err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy);
75 	if (err < 0)
76 		return err;
77 
78 	if (tb[TCA_SKBEDIT_PARMS] == NULL)
79 		return -EINVAL;
80 
81 	if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
82 		flags |= SKBEDIT_F_PRIORITY;
83 		priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
84 	}
85 
86 	if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
87 		flags |= SKBEDIT_F_QUEUE_MAPPING;
88 		queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
89 	}
90 
91 	if (tb[TCA_SKBEDIT_MARK] != NULL) {
92 		flags |= SKBEDIT_F_MARK;
93 		mark = nla_data(tb[TCA_SKBEDIT_MARK]);
94 	}
95 
96 	if (!flags)
97 		return -EINVAL;
98 
99 	parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
100 
101 	if (!tcf_hash_check(parm->index, a, bind)) {
102 		ret = tcf_hash_create(parm->index, est, a, sizeof(*d), bind);
103 		if (ret)
104 			return ret;
105 
106 		d = to_skbedit(a);
107 		ret = ACT_P_CREATED;
108 	} else {
109 		d = to_skbedit(a);
110 		if (bind)
111 			return 0;
112 		tcf_hash_release(a, bind);
113 		if (!ovr)
114 			return -EEXIST;
115 	}
116 
117 	spin_lock_bh(&d->tcf_lock);
118 
119 	d->flags = flags;
120 	if (flags & SKBEDIT_F_PRIORITY)
121 		d->priority = *priority;
122 	if (flags & SKBEDIT_F_QUEUE_MAPPING)
123 		d->queue_mapping = *queue_mapping;
124 	if (flags & SKBEDIT_F_MARK)
125 		d->mark = *mark;
126 
127 	d->tcf_action = parm->action;
128 
129 	spin_unlock_bh(&d->tcf_lock);
130 
131 	if (ret == ACT_P_CREATED)
132 		tcf_hash_insert(a);
133 	return ret;
134 }
135 
136 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
137 			    int bind, int ref)
138 {
139 	unsigned char *b = skb_tail_pointer(skb);
140 	struct tcf_skbedit *d = a->priv;
141 	struct tc_skbedit opt = {
142 		.index   = d->tcf_index,
143 		.refcnt  = d->tcf_refcnt - ref,
144 		.bindcnt = d->tcf_bindcnt - bind,
145 		.action  = d->tcf_action,
146 	};
147 	struct tcf_t t;
148 
149 	if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
150 		goto nla_put_failure;
151 	if ((d->flags & SKBEDIT_F_PRIORITY) &&
152 	    nla_put(skb, TCA_SKBEDIT_PRIORITY, sizeof(d->priority),
153 		    &d->priority))
154 		goto nla_put_failure;
155 	if ((d->flags & SKBEDIT_F_QUEUE_MAPPING) &&
156 	    nla_put(skb, TCA_SKBEDIT_QUEUE_MAPPING,
157 		    sizeof(d->queue_mapping), &d->queue_mapping))
158 		goto nla_put_failure;
159 	if ((d->flags & SKBEDIT_F_MARK) &&
160 	    nla_put(skb, TCA_SKBEDIT_MARK, sizeof(d->mark),
161 		    &d->mark))
162 		goto nla_put_failure;
163 	t.install = jiffies_to_clock_t(jiffies - d->tcf_tm.install);
164 	t.lastuse = jiffies_to_clock_t(jiffies - d->tcf_tm.lastuse);
165 	t.expires = jiffies_to_clock_t(d->tcf_tm.expires);
166 	if (nla_put(skb, TCA_SKBEDIT_TM, sizeof(t), &t))
167 		goto nla_put_failure;
168 	return skb->len;
169 
170 nla_put_failure:
171 	nlmsg_trim(skb, b);
172 	return -1;
173 }
174 
175 static struct tc_action_ops act_skbedit_ops = {
176 	.kind		=	"skbedit",
177 	.type		=	TCA_ACT_SKBEDIT,
178 	.owner		=	THIS_MODULE,
179 	.act		=	tcf_skbedit,
180 	.dump		=	tcf_skbedit_dump,
181 	.init		=	tcf_skbedit_init,
182 };
183 
184 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
185 MODULE_DESCRIPTION("SKB Editing");
186 MODULE_LICENSE("GPL");
187 
188 static int __init skbedit_init_module(void)
189 {
190 	return tcf_register_action(&act_skbedit_ops, SKBEDIT_TAB_MASK);
191 }
192 
193 static void __exit skbedit_cleanup_module(void)
194 {
195 	tcf_unregister_action(&act_skbedit_ops);
196 }
197 
198 module_init(skbedit_init_module);
199 module_exit(skbedit_cleanup_module);
200