xref: /openbmc/linux/net/sched/act_skbedit.c (revision bc5aa3a0)
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 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->mark;
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 };
65 
66 static int tcf_skbedit_init(struct net *net, struct nlattr *nla,
67 			    struct nlattr *est, struct tc_action **a,
68 			    int ovr, int bind)
69 {
70 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
71 	struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
72 	struct tc_skbedit *parm;
73 	struct tcf_skbedit *d;
74 	u32 flags = 0, *priority = NULL, *mark = NULL;
75 	u16 *queue_mapping = NULL, *ptype = NULL;
76 	bool exists = false;
77 	int ret = 0, err;
78 
79 	if (nla == NULL)
80 		return -EINVAL;
81 
82 	err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy);
83 	if (err < 0)
84 		return err;
85 
86 	if (tb[TCA_SKBEDIT_PARMS] == NULL)
87 		return -EINVAL;
88 
89 	if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
90 		flags |= SKBEDIT_F_PRIORITY;
91 		priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
92 	}
93 
94 	if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
95 		flags |= SKBEDIT_F_QUEUE_MAPPING;
96 		queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
97 	}
98 
99 	if (tb[TCA_SKBEDIT_PTYPE] != NULL) {
100 		ptype = nla_data(tb[TCA_SKBEDIT_PTYPE]);
101 		if (!skb_pkt_type_ok(*ptype))
102 			return -EINVAL;
103 		flags |= SKBEDIT_F_PTYPE;
104 	}
105 
106 	if (tb[TCA_SKBEDIT_MARK] != NULL) {
107 		flags |= SKBEDIT_F_MARK;
108 		mark = nla_data(tb[TCA_SKBEDIT_MARK]);
109 	}
110 
111 	parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
112 
113 	exists = tcf_hash_check(tn, parm->index, a, bind);
114 	if (exists && bind)
115 		return 0;
116 
117 	if (!flags) {
118 		tcf_hash_release(*a, bind);
119 		return -EINVAL;
120 	}
121 
122 	if (!exists) {
123 		ret = tcf_hash_create(tn, parm->index, est, a,
124 				      &act_skbedit_ops, bind, false);
125 		if (ret)
126 			return ret;
127 
128 		d = to_skbedit(*a);
129 		ret = ACT_P_CREATED;
130 	} else {
131 		d = to_skbedit(*a);
132 		tcf_hash_release(*a, bind);
133 		if (!ovr)
134 			return -EEXIST;
135 	}
136 
137 	spin_lock_bh(&d->tcf_lock);
138 
139 	d->flags = flags;
140 	if (flags & SKBEDIT_F_PRIORITY)
141 		d->priority = *priority;
142 	if (flags & SKBEDIT_F_QUEUE_MAPPING)
143 		d->queue_mapping = *queue_mapping;
144 	if (flags & SKBEDIT_F_MARK)
145 		d->mark = *mark;
146 	if (flags & SKBEDIT_F_PTYPE)
147 		d->ptype = *ptype;
148 
149 	d->tcf_action = parm->action;
150 
151 	spin_unlock_bh(&d->tcf_lock);
152 
153 	if (ret == ACT_P_CREATED)
154 		tcf_hash_insert(tn, *a);
155 	return ret;
156 }
157 
158 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
159 			    int bind, int ref)
160 {
161 	unsigned char *b = skb_tail_pointer(skb);
162 	struct tcf_skbedit *d = to_skbedit(a);
163 	struct tc_skbedit opt = {
164 		.index   = d->tcf_index,
165 		.refcnt  = d->tcf_refcnt - ref,
166 		.bindcnt = d->tcf_bindcnt - bind,
167 		.action  = d->tcf_action,
168 	};
169 	struct tcf_t t;
170 
171 	if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
172 		goto nla_put_failure;
173 	if ((d->flags & SKBEDIT_F_PRIORITY) &&
174 	    nla_put_u32(skb, TCA_SKBEDIT_PRIORITY, d->priority))
175 		goto nla_put_failure;
176 	if ((d->flags & SKBEDIT_F_QUEUE_MAPPING) &&
177 	    nla_put_u16(skb, TCA_SKBEDIT_QUEUE_MAPPING, d->queue_mapping))
178 		goto nla_put_failure;
179 	if ((d->flags & SKBEDIT_F_MARK) &&
180 	    nla_put_u32(skb, TCA_SKBEDIT_MARK, d->mark))
181 		goto nla_put_failure;
182 	if ((d->flags & SKBEDIT_F_PTYPE) &&
183 	    nla_put_u16(skb, TCA_SKBEDIT_PTYPE, d->ptype))
184 		goto nla_put_failure;
185 
186 	tcf_tm_dump(&t, &d->tcf_tm);
187 	if (nla_put_64bit(skb, TCA_SKBEDIT_TM, sizeof(t), &t, TCA_SKBEDIT_PAD))
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 int tcf_skbedit_walker(struct net *net, struct sk_buff *skb,
197 			      struct netlink_callback *cb, int type,
198 			      const struct tc_action_ops *ops)
199 {
200 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
201 
202 	return tcf_generic_walker(tn, skb, cb, type, ops);
203 }
204 
205 static int tcf_skbedit_search(struct net *net, struct tc_action **a, u32 index)
206 {
207 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
208 
209 	return tcf_hash_search(tn, a, index);
210 }
211 
212 static struct tc_action_ops act_skbedit_ops = {
213 	.kind		=	"skbedit",
214 	.type		=	TCA_ACT_SKBEDIT,
215 	.owner		=	THIS_MODULE,
216 	.act		=	tcf_skbedit,
217 	.dump		=	tcf_skbedit_dump,
218 	.init		=	tcf_skbedit_init,
219 	.walk		=	tcf_skbedit_walker,
220 	.lookup		=	tcf_skbedit_search,
221 	.size		=	sizeof(struct tcf_skbedit),
222 };
223 
224 static __net_init int skbedit_init_net(struct net *net)
225 {
226 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
227 
228 	return tc_action_net_init(tn, &act_skbedit_ops, SKBEDIT_TAB_MASK);
229 }
230 
231 static void __net_exit skbedit_exit_net(struct net *net)
232 {
233 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
234 
235 	tc_action_net_exit(tn);
236 }
237 
238 static struct pernet_operations skbedit_net_ops = {
239 	.init = skbedit_init_net,
240 	.exit = skbedit_exit_net,
241 	.id   = &skbedit_net_id,
242 	.size = sizeof(struct tc_action_net),
243 };
244 
245 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
246 MODULE_DESCRIPTION("SKB Editing");
247 MODULE_LICENSE("GPL");
248 
249 static int __init skbedit_init_module(void)
250 {
251 	return tcf_register_action(&act_skbedit_ops, &skbedit_net_ops);
252 }
253 
254 static void __exit skbedit_cleanup_module(void)
255 {
256 	tcf_unregister_action(&act_skbedit_ops, &skbedit_net_ops);
257 }
258 
259 module_init(skbedit_init_module);
260 module_exit(skbedit_cleanup_module);
261