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
32static struct tcf_common *tcf_skbedit_ht[SKBEDIT_TAB_MASK + 1];
33static u32 skbedit_idx_gen;
34static DEFINE_RWLOCK(skbedit_lock);
35
36static struct tcf_hashinfo skbedit_hash_info = {
37	.htab	=	tcf_skbedit_ht,
38	.hmask	=	SKBEDIT_TAB_MASK,
39	.lock	=	&skbedit_lock,
40};
41
42static int tcf_skbedit(struct sk_buff *skb, 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	d->tcf_bstats.bytes += qdisc_pkt_len(skb);
50	d->tcf_bstats.packets++;
51
52	if (d->flags & SKBEDIT_F_PRIORITY)
53		skb->priority = d->priority;
54	if (d->flags & SKBEDIT_F_QUEUE_MAPPING &&
55	    skb->dev->real_num_tx_queues > d->queue_mapping)
56		skb_set_queue_mapping(skb, d->queue_mapping);
57	if (d->flags & SKBEDIT_F_MARK)
58		skb->mark = d->mark;
59
60	spin_unlock(&d->tcf_lock);
61	return d->tcf_action;
62}
63
64static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
65	[TCA_SKBEDIT_PARMS]		= { .len = sizeof(struct tc_skbedit) },
66	[TCA_SKBEDIT_PRIORITY]		= { .len = sizeof(u32) },
67	[TCA_SKBEDIT_QUEUE_MAPPING]	= { .len = sizeof(u16) },
68	[TCA_SKBEDIT_MARK]		= { .len = sizeof(u32) },
69};
70
71static int tcf_skbedit_init(struct nlattr *nla, struct nlattr *est,
72			 struct tc_action *a, 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
148static inline 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
157static inline 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	NLA_PUT(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt);
171	if (d->flags & SKBEDIT_F_PRIORITY)
172		NLA_PUT(skb, TCA_SKBEDIT_PRIORITY, sizeof(d->priority),
173			&d->priority);
174	if (d->flags & SKBEDIT_F_QUEUE_MAPPING)
175		NLA_PUT(skb, TCA_SKBEDIT_QUEUE_MAPPING,
176			sizeof(d->queue_mapping), &d->queue_mapping);
177	if (d->flags & SKBEDIT_F_MARK)
178		NLA_PUT(skb, TCA_SKBEDIT_MARK, sizeof(d->mark),
179			&d->mark);
180	t.install = jiffies_to_clock_t(jiffies - d->tcf_tm.install);
181	t.lastuse = jiffies_to_clock_t(jiffies - d->tcf_tm.lastuse);
182	t.expires = jiffies_to_clock_t(d->tcf_tm.expires);
183	NLA_PUT(skb, TCA_SKBEDIT_TM, sizeof(t), &t);
184	return skb->len;
185
186nla_put_failure:
187	nlmsg_trim(skb, b);
188	return -1;
189}
190
191static struct tc_action_ops act_skbedit_ops = {
192	.kind		=	"skbedit",
193	.hinfo		=	&skbedit_hash_info,
194	.type		=	TCA_ACT_SKBEDIT,
195	.capab		=	TCA_CAP_NONE,
196	.owner		=	THIS_MODULE,
197	.act		=	tcf_skbedit,
198	.dump		=	tcf_skbedit_dump,
199	.cleanup	=	tcf_skbedit_cleanup,
200	.init		=	tcf_skbedit_init,
201	.walk		=	tcf_generic_walker,
202};
203
204MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
205MODULE_DESCRIPTION("SKB Editing");
206MODULE_LICENSE("GPL");
207
208static int __init skbedit_init_module(void)
209{
210	return tcf_register_action(&act_skbedit_ops);
211}
212
213static void __exit skbedit_cleanup_module(void)
214{
215	tcf_unregister_action(&act_skbedit_ops);
216}
217
218module_init(skbedit_init_module);
219module_exit(skbedit_cleanup_module);
220