xref: /linux/net/sched/act_skbedit.c (revision 2d87650a3bf1b80f7d0d150ee1af3f8a89e5b7aa)
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 u32 skbedit_idx_gen;
32 static struct tcf_hashinfo skbedit_hash_info;
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 nlattr *tb[TCA_SKBEDIT_MAX + 1];
67 	struct tc_skbedit *parm;
68 	struct tcf_skbedit *d;
69 	struct tcf_common *pc;
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 	pc = tcf_hash_check(parm->index, a, bind, &skbedit_hash_info);
105 	if (!pc) {
106 		pc = tcf_hash_create(parm->index, est, a, sizeof(*d), bind,
107 				     &skbedit_idx_gen, &skbedit_hash_info);
108 		if (IS_ERR(pc))
109 			return PTR_ERR(pc);
110 
111 		d = to_skbedit(pc);
112 		ret = ACT_P_CREATED;
113 	} else {
114 		d = to_skbedit(pc);
115 		if (!ovr) {
116 			tcf_hash_release(pc, bind, &skbedit_hash_info);
117 			return -EEXIST;
118 		}
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(pc, &skbedit_hash_info);
137 	return ret;
138 }
139 
140 static int tcf_skbedit_cleanup(struct tc_action *a, int bind)
141 {
142 	struct tcf_skbedit *d = a->priv;
143 
144 	if (d)
145 		return tcf_hash_release(&d->common, bind, &skbedit_hash_info);
146 	return 0;
147 }
148 
149 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
150 			    int bind, int ref)
151 {
152 	unsigned char *b = skb_tail_pointer(skb);
153 	struct tcf_skbedit *d = a->priv;
154 	struct tc_skbedit opt = {
155 		.index   = d->tcf_index,
156 		.refcnt  = d->tcf_refcnt - ref,
157 		.bindcnt = d->tcf_bindcnt - bind,
158 		.action  = d->tcf_action,
159 	};
160 	struct tcf_t t;
161 
162 	if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
163 		goto nla_put_failure;
164 	if ((d->flags & SKBEDIT_F_PRIORITY) &&
165 	    nla_put(skb, TCA_SKBEDIT_PRIORITY, sizeof(d->priority),
166 		    &d->priority))
167 		goto nla_put_failure;
168 	if ((d->flags & SKBEDIT_F_QUEUE_MAPPING) &&
169 	    nla_put(skb, TCA_SKBEDIT_QUEUE_MAPPING,
170 		    sizeof(d->queue_mapping), &d->queue_mapping))
171 		goto nla_put_failure;
172 	if ((d->flags & SKBEDIT_F_MARK) &&
173 	    nla_put(skb, TCA_SKBEDIT_MARK, sizeof(d->mark),
174 		    &d->mark))
175 		goto nla_put_failure;
176 	t.install = jiffies_to_clock_t(jiffies - d->tcf_tm.install);
177 	t.lastuse = jiffies_to_clock_t(jiffies - d->tcf_tm.lastuse);
178 	t.expires = jiffies_to_clock_t(d->tcf_tm.expires);
179 	if (nla_put(skb, TCA_SKBEDIT_TM, sizeof(t), &t))
180 		goto nla_put_failure;
181 	return skb->len;
182 
183 nla_put_failure:
184 	nlmsg_trim(skb, b);
185 	return -1;
186 }
187 
188 static struct tc_action_ops act_skbedit_ops = {
189 	.kind		=	"skbedit",
190 	.hinfo		=	&skbedit_hash_info,
191 	.type		=	TCA_ACT_SKBEDIT,
192 	.capab		=	TCA_CAP_NONE,
193 	.owner		=	THIS_MODULE,
194 	.act		=	tcf_skbedit,
195 	.dump		=	tcf_skbedit_dump,
196 	.cleanup	=	tcf_skbedit_cleanup,
197 	.init		=	tcf_skbedit_init,
198 };
199 
200 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
201 MODULE_DESCRIPTION("SKB Editing");
202 MODULE_LICENSE("GPL");
203 
204 static int __init skbedit_init_module(void)
205 {
206 	int err = tcf_hashinfo_init(&skbedit_hash_info, SKBEDIT_TAB_MASK);
207 	if (err)
208 		return err;
209 	return tcf_register_action(&act_skbedit_ops);
210 }
211 
212 static void __exit skbedit_cleanup_module(void)
213 {
214 	tcf_hashinfo_destroy(&skbedit_hash_info);
215 	tcf_unregister_action(&act_skbedit_ops);
216 }
217 
218 module_init(skbedit_init_module);
219 module_exit(skbedit_cleanup_module);
220