xref: /openbmc/linux/net/sched/act_skbedit.c (revision 239480ab)
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 unsigned int skbedit_net_id;
33 static struct tc_action_ops act_skbedit_ops;
34 
35 static int tcf_skbedit(struct sk_buff *skb, const struct tc_action *a,
36 		       struct tcf_result *res)
37 {
38 	struct tcf_skbedit *d = to_skbedit(a);
39 
40 	spin_lock(&d->tcf_lock);
41 	tcf_lastuse_update(&d->tcf_tm);
42 	bstats_update(&d->tcf_bstats, skb);
43 
44 	if (d->flags & SKBEDIT_F_PRIORITY)
45 		skb->priority = d->priority;
46 	if (d->flags & SKBEDIT_F_QUEUE_MAPPING &&
47 	    skb->dev->real_num_tx_queues > d->queue_mapping)
48 		skb_set_queue_mapping(skb, d->queue_mapping);
49 	if (d->flags & SKBEDIT_F_MARK) {
50 		skb->mark &= ~d->mask;
51 		skb->mark |= d->mark & d->mask;
52 	}
53 	if (d->flags & SKBEDIT_F_PTYPE)
54 		skb->pkt_type = d->ptype;
55 
56 	spin_unlock(&d->tcf_lock);
57 	return d->tcf_action;
58 }
59 
60 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
61 	[TCA_SKBEDIT_PARMS]		= { .len = sizeof(struct tc_skbedit) },
62 	[TCA_SKBEDIT_PRIORITY]		= { .len = sizeof(u32) },
63 	[TCA_SKBEDIT_QUEUE_MAPPING]	= { .len = sizeof(u16) },
64 	[TCA_SKBEDIT_MARK]		= { .len = sizeof(u32) },
65 	[TCA_SKBEDIT_PTYPE]		= { .len = sizeof(u16) },
66 	[TCA_SKBEDIT_MASK]		= { .len = sizeof(u32) },
67 };
68 
69 static int tcf_skbedit_init(struct net *net, struct nlattr *nla,
70 			    struct nlattr *est, struct tc_action **a,
71 			    int ovr, int bind)
72 {
73 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
74 	struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
75 	struct tc_skbedit *parm;
76 	struct tcf_skbedit *d;
77 	u32 flags = 0, *priority = NULL, *mark = NULL, *mask = NULL;
78 	u16 *queue_mapping = NULL, *ptype = NULL;
79 	bool exists = false;
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, NULL);
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_PTYPE] != NULL) {
103 		ptype = nla_data(tb[TCA_SKBEDIT_PTYPE]);
104 		if (!skb_pkt_type_ok(*ptype))
105 			return -EINVAL;
106 		flags |= SKBEDIT_F_PTYPE;
107 	}
108 
109 	if (tb[TCA_SKBEDIT_MARK] != NULL) {
110 		flags |= SKBEDIT_F_MARK;
111 		mark = nla_data(tb[TCA_SKBEDIT_MARK]);
112 	}
113 
114 	if (tb[TCA_SKBEDIT_MASK] != NULL) {
115 		flags |= SKBEDIT_F_MASK;
116 		mask = nla_data(tb[TCA_SKBEDIT_MASK]);
117 	}
118 
119 	parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
120 
121 	exists = tcf_hash_check(tn, parm->index, a, bind);
122 	if (exists && bind)
123 		return 0;
124 
125 	if (!flags) {
126 		tcf_hash_release(*a, bind);
127 		return -EINVAL;
128 	}
129 
130 	if (!exists) {
131 		ret = tcf_hash_create(tn, parm->index, est, a,
132 				      &act_skbedit_ops, bind, false);
133 		if (ret)
134 			return ret;
135 
136 		d = to_skbedit(*a);
137 		ret = ACT_P_CREATED;
138 	} else {
139 		d = to_skbedit(*a);
140 		tcf_hash_release(*a, bind);
141 		if (!ovr)
142 			return -EEXIST;
143 	}
144 
145 	spin_lock_bh(&d->tcf_lock);
146 
147 	d->flags = flags;
148 	if (flags & SKBEDIT_F_PRIORITY)
149 		d->priority = *priority;
150 	if (flags & SKBEDIT_F_QUEUE_MAPPING)
151 		d->queue_mapping = *queue_mapping;
152 	if (flags & SKBEDIT_F_MARK)
153 		d->mark = *mark;
154 	if (flags & SKBEDIT_F_PTYPE)
155 		d->ptype = *ptype;
156 	/* default behaviour is to use all the bits */
157 	d->mask = 0xffffffff;
158 	if (flags & SKBEDIT_F_MASK)
159 		d->mask = *mask;
160 
161 	d->tcf_action = parm->action;
162 
163 	spin_unlock_bh(&d->tcf_lock);
164 
165 	if (ret == ACT_P_CREATED)
166 		tcf_hash_insert(tn, *a);
167 	return ret;
168 }
169 
170 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
171 			    int bind, int ref)
172 {
173 	unsigned char *b = skb_tail_pointer(skb);
174 	struct tcf_skbedit *d = to_skbedit(a);
175 	struct tc_skbedit opt = {
176 		.index   = d->tcf_index,
177 		.refcnt  = d->tcf_refcnt - ref,
178 		.bindcnt = d->tcf_bindcnt - bind,
179 		.action  = d->tcf_action,
180 	};
181 	struct tcf_t t;
182 
183 	if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
184 		goto nla_put_failure;
185 	if ((d->flags & SKBEDIT_F_PRIORITY) &&
186 	    nla_put_u32(skb, TCA_SKBEDIT_PRIORITY, d->priority))
187 		goto nla_put_failure;
188 	if ((d->flags & SKBEDIT_F_QUEUE_MAPPING) &&
189 	    nla_put_u16(skb, TCA_SKBEDIT_QUEUE_MAPPING, d->queue_mapping))
190 		goto nla_put_failure;
191 	if ((d->flags & SKBEDIT_F_MARK) &&
192 	    nla_put_u32(skb, TCA_SKBEDIT_MARK, d->mark))
193 		goto nla_put_failure;
194 	if ((d->flags & SKBEDIT_F_PTYPE) &&
195 	    nla_put_u16(skb, TCA_SKBEDIT_PTYPE, d->ptype))
196 		goto nla_put_failure;
197 	if ((d->flags & SKBEDIT_F_MASK) &&
198 	    nla_put_u32(skb, TCA_SKBEDIT_MASK, d->mask))
199 		goto nla_put_failure;
200 
201 	tcf_tm_dump(&t, &d->tcf_tm);
202 	if (nla_put_64bit(skb, TCA_SKBEDIT_TM, sizeof(t), &t, TCA_SKBEDIT_PAD))
203 		goto nla_put_failure;
204 	return skb->len;
205 
206 nla_put_failure:
207 	nlmsg_trim(skb, b);
208 	return -1;
209 }
210 
211 static int tcf_skbedit_walker(struct net *net, struct sk_buff *skb,
212 			      struct netlink_callback *cb, int type,
213 			      const struct tc_action_ops *ops)
214 {
215 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
216 
217 	return tcf_generic_walker(tn, skb, cb, type, ops);
218 }
219 
220 static int tcf_skbedit_search(struct net *net, struct tc_action **a, u32 index)
221 {
222 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
223 
224 	return tcf_hash_search(tn, a, index);
225 }
226 
227 static struct tc_action_ops act_skbedit_ops = {
228 	.kind		=	"skbedit",
229 	.type		=	TCA_ACT_SKBEDIT,
230 	.owner		=	THIS_MODULE,
231 	.act		=	tcf_skbedit,
232 	.dump		=	tcf_skbedit_dump,
233 	.init		=	tcf_skbedit_init,
234 	.walk		=	tcf_skbedit_walker,
235 	.lookup		=	tcf_skbedit_search,
236 	.size		=	sizeof(struct tcf_skbedit),
237 };
238 
239 static __net_init int skbedit_init_net(struct net *net)
240 {
241 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
242 
243 	return tc_action_net_init(tn, &act_skbedit_ops, SKBEDIT_TAB_MASK);
244 }
245 
246 static void __net_exit skbedit_exit_net(struct net *net)
247 {
248 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
249 
250 	tc_action_net_exit(tn);
251 }
252 
253 static struct pernet_operations skbedit_net_ops = {
254 	.init = skbedit_init_net,
255 	.exit = skbedit_exit_net,
256 	.id   = &skbedit_net_id,
257 	.size = sizeof(struct tc_action_net),
258 };
259 
260 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
261 MODULE_DESCRIPTION("SKB Editing");
262 MODULE_LICENSE("GPL");
263 
264 static int __init skbedit_init_module(void)
265 {
266 	return tcf_register_action(&act_skbedit_ops, &skbedit_net_ops);
267 }
268 
269 static void __exit skbedit_cleanup_module(void)
270 {
271 	tcf_unregister_action(&act_skbedit_ops, &skbedit_net_ops);
272 }
273 
274 module_init(skbedit_init_module);
275 module_exit(skbedit_cleanup_module);
276