xref: /linux/net/sched/act_skbedit.c (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
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, write to the Free Software Foundation, Inc., 59 Temple
15  * Place - Suite 330, Boston, MA 02111-1307 USA.
16  *
17  * Author: Alexander Duyck <alexander.h.duyck@intel.com>
18  */
19 
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/kernel.h>
23 #include <linux/skbuff.h>
24 #include <linux/rtnetlink.h>
25 #include <net/netlink.h>
26 #include <net/pkt_sched.h>
27 
28 #include <linux/tc_act/tc_skbedit.h>
29 #include <net/tc_act/tc_skbedit.h>
30 
31 #define SKBEDIT_TAB_MASK     15
32 static struct tcf_common *tcf_skbedit_ht[SKBEDIT_TAB_MASK + 1];
33 static u32 skbedit_idx_gen;
34 static DEFINE_RWLOCK(skbedit_lock);
35 
36 static struct tcf_hashinfo skbedit_hash_info = {
37 	.htab	=	tcf_skbedit_ht,
38 	.hmask	=	SKBEDIT_TAB_MASK,
39 	.lock	=	&skbedit_lock,
40 };
41 
42 static int tcf_skbedit(struct sk_buff *skb, const struct tc_action *a,
43 		       struct tcf_result *res)
44 {
45 	struct tcf_skbedit *d = a->priv;
46 
47 	spin_lock(&d->tcf_lock);
48 	d->tcf_tm.lastuse = jiffies;
49 	bstats_update(&d->tcf_bstats, skb);
50 
51 	if (d->flags & SKBEDIT_F_PRIORITY)
52 		skb->priority = d->priority;
53 	if (d->flags & SKBEDIT_F_QUEUE_MAPPING &&
54 	    skb->dev->real_num_tx_queues > d->queue_mapping)
55 		skb_set_queue_mapping(skb, d->queue_mapping);
56 	if (d->flags & SKBEDIT_F_MARK)
57 		skb->mark = d->mark;
58 
59 	spin_unlock(&d->tcf_lock);
60 	return d->tcf_action;
61 }
62 
63 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
64 	[TCA_SKBEDIT_PARMS]		= { .len = sizeof(struct tc_skbedit) },
65 	[TCA_SKBEDIT_PRIORITY]		= { .len = sizeof(u32) },
66 	[TCA_SKBEDIT_QUEUE_MAPPING]	= { .len = sizeof(u16) },
67 	[TCA_SKBEDIT_MARK]		= { .len = sizeof(u32) },
68 };
69 
70 static int tcf_skbedit_init(struct net *net, struct nlattr *nla,
71 			    struct nlattr *est, struct tc_action *a,
72 			    int ovr, int bind)
73 {
74 	struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
75 	struct tc_skbedit *parm;
76 	struct tcf_skbedit *d;
77 	struct tcf_common *pc;
78 	u32 flags = 0, *priority = NULL, *mark = NULL;
79 	u16 *queue_mapping = NULL;
80 	int ret = 0, err;
81 
82 	if (nla == NULL)
83 		return -EINVAL;
84 
85 	err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy);
86 	if (err < 0)
87 		return err;
88 
89 	if (tb[TCA_SKBEDIT_PARMS] == NULL)
90 		return -EINVAL;
91 
92 	if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
93 		flags |= SKBEDIT_F_PRIORITY;
94 		priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
95 	}
96 
97 	if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
98 		flags |= SKBEDIT_F_QUEUE_MAPPING;
99 		queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
100 	}
101 
102 	if (tb[TCA_SKBEDIT_MARK] != NULL) {
103 		flags |= SKBEDIT_F_MARK;
104 		mark = nla_data(tb[TCA_SKBEDIT_MARK]);
105 	}
106 
107 	if (!flags)
108 		return -EINVAL;
109 
110 	parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
111 
112 	pc = tcf_hash_check(parm->index, a, bind, &skbedit_hash_info);
113 	if (!pc) {
114 		pc = tcf_hash_create(parm->index, est, a, sizeof(*d), bind,
115 				     &skbedit_idx_gen, &skbedit_hash_info);
116 		if (IS_ERR(pc))
117 			return PTR_ERR(pc);
118 
119 		d = to_skbedit(pc);
120 		ret = ACT_P_CREATED;
121 	} else {
122 		d = to_skbedit(pc);
123 		if (!ovr) {
124 			tcf_hash_release(pc, bind, &skbedit_hash_info);
125 			return -EEXIST;
126 		}
127 	}
128 
129 	spin_lock_bh(&d->tcf_lock);
130 
131 	d->flags = flags;
132 	if (flags & SKBEDIT_F_PRIORITY)
133 		d->priority = *priority;
134 	if (flags & SKBEDIT_F_QUEUE_MAPPING)
135 		d->queue_mapping = *queue_mapping;
136 	if (flags & SKBEDIT_F_MARK)
137 		d->mark = *mark;
138 
139 	d->tcf_action = parm->action;
140 
141 	spin_unlock_bh(&d->tcf_lock);
142 
143 	if (ret == ACT_P_CREATED)
144 		tcf_hash_insert(pc, &skbedit_hash_info);
145 	return ret;
146 }
147 
148 static int tcf_skbedit_cleanup(struct tc_action *a, int bind)
149 {
150 	struct tcf_skbedit *d = a->priv;
151 
152 	if (d)
153 		return tcf_hash_release(&d->common, bind, &skbedit_hash_info);
154 	return 0;
155 }
156 
157 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
158 			    int bind, int ref)
159 {
160 	unsigned char *b = skb_tail_pointer(skb);
161 	struct tcf_skbedit *d = a->priv;
162 	struct tc_skbedit opt = {
163 		.index   = d->tcf_index,
164 		.refcnt  = d->tcf_refcnt - ref,
165 		.bindcnt = d->tcf_bindcnt - bind,
166 		.action  = d->tcf_action,
167 	};
168 	struct tcf_t t;
169 
170 	if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
171 		goto nla_put_failure;
172 	if ((d->flags & SKBEDIT_F_PRIORITY) &&
173 	    nla_put(skb, TCA_SKBEDIT_PRIORITY, sizeof(d->priority),
174 		    &d->priority))
175 		goto nla_put_failure;
176 	if ((d->flags & SKBEDIT_F_QUEUE_MAPPING) &&
177 	    nla_put(skb, TCA_SKBEDIT_QUEUE_MAPPING,
178 		    sizeof(d->queue_mapping), &d->queue_mapping))
179 		goto nla_put_failure;
180 	if ((d->flags & SKBEDIT_F_MARK) &&
181 	    nla_put(skb, TCA_SKBEDIT_MARK, sizeof(d->mark),
182 		    &d->mark))
183 		goto nla_put_failure;
184 	t.install = jiffies_to_clock_t(jiffies - d->tcf_tm.install);
185 	t.lastuse = jiffies_to_clock_t(jiffies - d->tcf_tm.lastuse);
186 	t.expires = jiffies_to_clock_t(d->tcf_tm.expires);
187 	if (nla_put(skb, TCA_SKBEDIT_TM, sizeof(t), &t))
188 		goto nla_put_failure;
189 	return skb->len;
190 
191 nla_put_failure:
192 	nlmsg_trim(skb, b);
193 	return -1;
194 }
195 
196 static struct tc_action_ops act_skbedit_ops = {
197 	.kind		=	"skbedit",
198 	.hinfo		=	&skbedit_hash_info,
199 	.type		=	TCA_ACT_SKBEDIT,
200 	.capab		=	TCA_CAP_NONE,
201 	.owner		=	THIS_MODULE,
202 	.act		=	tcf_skbedit,
203 	.dump		=	tcf_skbedit_dump,
204 	.cleanup	=	tcf_skbedit_cleanup,
205 	.init		=	tcf_skbedit_init,
206 };
207 
208 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
209 MODULE_DESCRIPTION("SKB Editing");
210 MODULE_LICENSE("GPL");
211 
212 static int __init skbedit_init_module(void)
213 {
214 	return tcf_register_action(&act_skbedit_ops);
215 }
216 
217 static void __exit skbedit_cleanup_module(void)
218 {
219 	tcf_unregister_action(&act_skbedit_ops);
220 }
221 
222 module_init(skbedit_init_module);
223 module_exit(skbedit_cleanup_module);
224