xref: /openbmc/linux/net/sched/act_skbedit.c (revision 82e6fdd6)
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 static unsigned int skbedit_net_id;
31 static struct tc_action_ops act_skbedit_ops;
32 
33 static int tcf_skbedit(struct sk_buff *skb, const struct tc_action *a,
34 		       struct tcf_result *res)
35 {
36 	struct tcf_skbedit *d = to_skbedit(a);
37 
38 	spin_lock(&d->tcf_lock);
39 	tcf_lastuse_update(&d->tcf_tm);
40 	bstats_update(&d->tcf_bstats, skb);
41 
42 	if (d->flags & SKBEDIT_F_PRIORITY)
43 		skb->priority = d->priority;
44 	if (d->flags & SKBEDIT_F_QUEUE_MAPPING &&
45 	    skb->dev->real_num_tx_queues > d->queue_mapping)
46 		skb_set_queue_mapping(skb, d->queue_mapping);
47 	if (d->flags & SKBEDIT_F_MARK) {
48 		skb->mark &= ~d->mask;
49 		skb->mark |= d->mark & d->mask;
50 	}
51 	if (d->flags & SKBEDIT_F_PTYPE)
52 		skb->pkt_type = d->ptype;
53 
54 	spin_unlock(&d->tcf_lock);
55 	return d->tcf_action;
56 }
57 
58 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
59 	[TCA_SKBEDIT_PARMS]		= { .len = sizeof(struct tc_skbedit) },
60 	[TCA_SKBEDIT_PRIORITY]		= { .len = sizeof(u32) },
61 	[TCA_SKBEDIT_QUEUE_MAPPING]	= { .len = sizeof(u16) },
62 	[TCA_SKBEDIT_MARK]		= { .len = sizeof(u32) },
63 	[TCA_SKBEDIT_PTYPE]		= { .len = sizeof(u16) },
64 	[TCA_SKBEDIT_MASK]		= { .len = sizeof(u32) },
65 };
66 
67 static int tcf_skbedit_init(struct net *net, struct nlattr *nla,
68 			    struct nlattr *est, struct tc_action **a,
69 			    int ovr, int bind)
70 {
71 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
72 	struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
73 	struct tc_skbedit *parm;
74 	struct tcf_skbedit *d;
75 	u32 flags = 0, *priority = NULL, *mark = NULL, *mask = NULL;
76 	u16 *queue_mapping = NULL, *ptype = NULL;
77 	bool exists = false;
78 	int ret = 0, err;
79 
80 	if (nla == NULL)
81 		return -EINVAL;
82 
83 	err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy, NULL);
84 	if (err < 0)
85 		return err;
86 
87 	if (tb[TCA_SKBEDIT_PARMS] == NULL)
88 		return -EINVAL;
89 
90 	if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
91 		flags |= SKBEDIT_F_PRIORITY;
92 		priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
93 	}
94 
95 	if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
96 		flags |= SKBEDIT_F_QUEUE_MAPPING;
97 		queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
98 	}
99 
100 	if (tb[TCA_SKBEDIT_PTYPE] != NULL) {
101 		ptype = nla_data(tb[TCA_SKBEDIT_PTYPE]);
102 		if (!skb_pkt_type_ok(*ptype))
103 			return -EINVAL;
104 		flags |= SKBEDIT_F_PTYPE;
105 	}
106 
107 	if (tb[TCA_SKBEDIT_MARK] != NULL) {
108 		flags |= SKBEDIT_F_MARK;
109 		mark = nla_data(tb[TCA_SKBEDIT_MARK]);
110 	}
111 
112 	if (tb[TCA_SKBEDIT_MASK] != NULL) {
113 		flags |= SKBEDIT_F_MASK;
114 		mask = nla_data(tb[TCA_SKBEDIT_MASK]);
115 	}
116 
117 	parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
118 
119 	exists = tcf_idr_check(tn, parm->index, a, bind);
120 	if (exists && bind)
121 		return 0;
122 
123 	if (!flags) {
124 		tcf_idr_release(*a, bind);
125 		return -EINVAL;
126 	}
127 
128 	if (!exists) {
129 		ret = tcf_idr_create(tn, parm->index, est, a,
130 				     &act_skbedit_ops, bind, false);
131 		if (ret)
132 			return ret;
133 
134 		d = to_skbedit(*a);
135 		ret = ACT_P_CREATED;
136 	} else {
137 		d = to_skbedit(*a);
138 		tcf_idr_release(*a, bind);
139 		if (!ovr)
140 			return -EEXIST;
141 	}
142 
143 	spin_lock_bh(&d->tcf_lock);
144 
145 	d->flags = flags;
146 	if (flags & SKBEDIT_F_PRIORITY)
147 		d->priority = *priority;
148 	if (flags & SKBEDIT_F_QUEUE_MAPPING)
149 		d->queue_mapping = *queue_mapping;
150 	if (flags & SKBEDIT_F_MARK)
151 		d->mark = *mark;
152 	if (flags & SKBEDIT_F_PTYPE)
153 		d->ptype = *ptype;
154 	/* default behaviour is to use all the bits */
155 	d->mask = 0xffffffff;
156 	if (flags & SKBEDIT_F_MASK)
157 		d->mask = *mask;
158 
159 	d->tcf_action = parm->action;
160 
161 	spin_unlock_bh(&d->tcf_lock);
162 
163 	if (ret == ACT_P_CREATED)
164 		tcf_idr_insert(tn, *a);
165 	return ret;
166 }
167 
168 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
169 			    int bind, int ref)
170 {
171 	unsigned char *b = skb_tail_pointer(skb);
172 	struct tcf_skbedit *d = to_skbedit(a);
173 	struct tc_skbedit opt = {
174 		.index   = d->tcf_index,
175 		.refcnt  = d->tcf_refcnt - ref,
176 		.bindcnt = d->tcf_bindcnt - bind,
177 		.action  = d->tcf_action,
178 	};
179 	struct tcf_t t;
180 
181 	if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
182 		goto nla_put_failure;
183 	if ((d->flags & SKBEDIT_F_PRIORITY) &&
184 	    nla_put_u32(skb, TCA_SKBEDIT_PRIORITY, d->priority))
185 		goto nla_put_failure;
186 	if ((d->flags & SKBEDIT_F_QUEUE_MAPPING) &&
187 	    nla_put_u16(skb, TCA_SKBEDIT_QUEUE_MAPPING, d->queue_mapping))
188 		goto nla_put_failure;
189 	if ((d->flags & SKBEDIT_F_MARK) &&
190 	    nla_put_u32(skb, TCA_SKBEDIT_MARK, d->mark))
191 		goto nla_put_failure;
192 	if ((d->flags & SKBEDIT_F_PTYPE) &&
193 	    nla_put_u16(skb, TCA_SKBEDIT_PTYPE, d->ptype))
194 		goto nla_put_failure;
195 	if ((d->flags & SKBEDIT_F_MASK) &&
196 	    nla_put_u32(skb, TCA_SKBEDIT_MASK, d->mask))
197 		goto nla_put_failure;
198 
199 	tcf_tm_dump(&t, &d->tcf_tm);
200 	if (nla_put_64bit(skb, TCA_SKBEDIT_TM, sizeof(t), &t, TCA_SKBEDIT_PAD))
201 		goto nla_put_failure;
202 	return skb->len;
203 
204 nla_put_failure:
205 	nlmsg_trim(skb, b);
206 	return -1;
207 }
208 
209 static int tcf_skbedit_walker(struct net *net, struct sk_buff *skb,
210 			      struct netlink_callback *cb, int type,
211 			      const struct tc_action_ops *ops)
212 {
213 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
214 
215 	return tcf_generic_walker(tn, skb, cb, type, ops);
216 }
217 
218 static int tcf_skbedit_search(struct net *net, struct tc_action **a, u32 index)
219 {
220 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
221 
222 	return tcf_idr_search(tn, a, index);
223 }
224 
225 static struct tc_action_ops act_skbedit_ops = {
226 	.kind		=	"skbedit",
227 	.type		=	TCA_ACT_SKBEDIT,
228 	.owner		=	THIS_MODULE,
229 	.act		=	tcf_skbedit,
230 	.dump		=	tcf_skbedit_dump,
231 	.init		=	tcf_skbedit_init,
232 	.walk		=	tcf_skbedit_walker,
233 	.lookup		=	tcf_skbedit_search,
234 	.size		=	sizeof(struct tcf_skbedit),
235 };
236 
237 static __net_init int skbedit_init_net(struct net *net)
238 {
239 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
240 
241 	return tc_action_net_init(tn, &act_skbedit_ops);
242 }
243 
244 static void __net_exit skbedit_exit_net(struct list_head *net_list)
245 {
246 	tc_action_net_exit(net_list, skbedit_net_id);
247 }
248 
249 static struct pernet_operations skbedit_net_ops = {
250 	.init = skbedit_init_net,
251 	.exit_batch = skbedit_exit_net,
252 	.id   = &skbedit_net_id,
253 	.size = sizeof(struct tc_action_net),
254 };
255 
256 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
257 MODULE_DESCRIPTION("SKB Editing");
258 MODULE_LICENSE("GPL");
259 
260 static int __init skbedit_init_module(void)
261 {
262 	return tcf_register_action(&act_skbedit_ops, &skbedit_net_ops);
263 }
264 
265 static void __exit skbedit_cleanup_module(void)
266 {
267 	tcf_unregister_action(&act_skbedit_ops, &skbedit_net_ops);
268 }
269 
270 module_init(skbedit_init_module);
271 module_exit(skbedit_cleanup_module);
272