net/sched: prepare TC actions to properly validate the control action
[linux-2.6-block.git] / net / sched / act_skbedit.c
CommitLineData
ca9b0e27
AD
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
c057b190 14 * this program; if not, see <http://www.gnu.org/licenses/>.
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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>
e7e3728b
QF
26#include <net/ip.h>
27#include <net/ipv6.h>
28#include <net/dsfield.h>
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29
30#include <linux/tc_act/tc_skbedit.h>
31#include <net/tc_act/tc_skbedit.h>
32
c7d03a00 33static unsigned int skbedit_net_id;
a85a970a 34static struct tc_action_ops act_skbedit_ops;
ddf97ccd 35
45da1dac
JHS
36static int tcf_skbedit_act(struct sk_buff *skb, const struct tc_action *a,
37 struct tcf_result *res)
ca9b0e27 38{
a85a970a 39 struct tcf_skbedit *d = to_skbedit(a);
c749cdda
DC
40 struct tcf_skbedit_params *params;
41 int action;
ca9b0e27 42
9c4a4e48 43 tcf_lastuse_update(&d->tcf_tm);
6f3dfb0d 44 bstats_cpu_update(this_cpu_ptr(d->common.cpu_bstats), skb);
ca9b0e27 45
7fd4b288 46 params = rcu_dereference_bh(d->params);
c749cdda
DC
47 action = READ_ONCE(d->tcf_action);
48
49 if (params->flags & SKBEDIT_F_PRIORITY)
50 skb->priority = params->priority;
51 if (params->flags & SKBEDIT_F_INHERITDSFIELD) {
e7e3728b
QF
52 int wlen = skb_network_offset(skb);
53
54 switch (tc_skb_protocol(skb)) {
55 case htons(ETH_P_IP):
56 wlen += sizeof(struct iphdr);
57 if (!pskb_may_pull(skb, wlen))
58 goto err;
59 skb->priority = ipv4_get_dsfield(ip_hdr(skb)) >> 2;
60 break;
61
62 case htons(ETH_P_IPV6):
63 wlen += sizeof(struct ipv6hdr);
64 if (!pskb_may_pull(skb, wlen))
65 goto err;
66 skb->priority = ipv6_get_dsfield(ipv6_hdr(skb)) >> 2;
67 break;
68 }
69 }
c749cdda
DC
70 if (params->flags & SKBEDIT_F_QUEUE_MAPPING &&
71 skb->dev->real_num_tx_queues > params->queue_mapping)
72 skb_set_queue_mapping(skb, params->queue_mapping);
73 if (params->flags & SKBEDIT_F_MARK) {
74 skb->mark &= ~params->mask;
75 skb->mark |= params->mark & params->mask;
4fe77d82 76 }
c749cdda
DC
77 if (params->flags & SKBEDIT_F_PTYPE)
78 skb->pkt_type = params->ptype;
c749cdda 79 return action;
7fd4b288 80
e7e3728b 81err:
6f3dfb0d 82 qstats_drop_inc(this_cpu_ptr(d->common.cpu_qstats));
7fd4b288 83 return TC_ACT_SHOT;
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AD
84}
85
86static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
87 [TCA_SKBEDIT_PARMS] = { .len = sizeof(struct tc_skbedit) },
88 [TCA_SKBEDIT_PRIORITY] = { .len = sizeof(u32) },
89 [TCA_SKBEDIT_QUEUE_MAPPING] = { .len = sizeof(u16) },
1c55d62e 90 [TCA_SKBEDIT_MARK] = { .len = sizeof(u32) },
ff202ee1 91 [TCA_SKBEDIT_PTYPE] = { .len = sizeof(u16) },
4fe77d82 92 [TCA_SKBEDIT_MASK] = { .len = sizeof(u32) },
e7e3728b 93 [TCA_SKBEDIT_FLAGS] = { .len = sizeof(u64) },
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AD
94};
95
c1b52739 96static int tcf_skbedit_init(struct net *net, struct nlattr *nla,
a85a970a 97 struct nlattr *est, struct tc_action **a,
789871bb 98 int ovr, int bind, bool rtnl_held,
85d0966f 99 struct tcf_proto *tp,
789871bb 100 struct netlink_ext_ack *extack)
ca9b0e27 101{
ddf97ccd 102 struct tc_action_net *tn = net_generic(net, skbedit_net_id);
6d7a8df6 103 struct tcf_skbedit_params *params_new;
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AD
104 struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
105 struct tc_skbedit *parm;
106 struct tcf_skbedit *d;
4fe77d82 107 u32 flags = 0, *priority = NULL, *mark = NULL, *mask = NULL;
ff202ee1 108 u16 *queue_mapping = NULL, *ptype = NULL;
b2313077
WC
109 bool exists = false;
110 int ret = 0, err;
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AD
111
112 if (nla == NULL)
113 return -EINVAL;
114
fceb6435 115 err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy, NULL);
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116 if (err < 0)
117 return err;
118
119 if (tb[TCA_SKBEDIT_PARMS] == NULL)
120 return -EINVAL;
121
122 if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
123 flags |= SKBEDIT_F_PRIORITY;
124 priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
125 }
126
127 if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
128 flags |= SKBEDIT_F_QUEUE_MAPPING;
129 queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
130 }
1c55d62e 131
ff202ee1
JHS
132 if (tb[TCA_SKBEDIT_PTYPE] != NULL) {
133 ptype = nla_data(tb[TCA_SKBEDIT_PTYPE]);
134 if (!skb_pkt_type_ok(*ptype))
135 return -EINVAL;
136 flags |= SKBEDIT_F_PTYPE;
137 }
138
1c55d62e 139 if (tb[TCA_SKBEDIT_MARK] != NULL) {
140 flags |= SKBEDIT_F_MARK;
141 mark = nla_data(tb[TCA_SKBEDIT_MARK]);
142 }
143
4fe77d82
AQ
144 if (tb[TCA_SKBEDIT_MASK] != NULL) {
145 flags |= SKBEDIT_F_MASK;
146 mask = nla_data(tb[TCA_SKBEDIT_MASK]);
147 }
148
e7e3728b
QF
149 if (tb[TCA_SKBEDIT_FLAGS] != NULL) {
150 u64 *pure_flags = nla_data(tb[TCA_SKBEDIT_FLAGS]);
151
152 if (*pure_flags & SKBEDIT_F_INHERITDSFIELD)
153 flags |= SKBEDIT_F_INHERITDSFIELD;
154 }
155
ca9b0e27
AD
156 parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
157
0190c1d4
VB
158 err = tcf_idr_check_alloc(tn, &parm->index, a, bind);
159 if (err < 0)
160 return err;
161 exists = err;
5e1567ae
JHS
162 if (exists && bind)
163 return 0;
164
165 if (!flags) {
af5d0184
RM
166 if (exists)
167 tcf_idr_release(*a, bind);
0190c1d4
VB
168 else
169 tcf_idr_cleanup(tn, parm->index);
5e1567ae
JHS
170 return -EINVAL;
171 }
172
173 if (!exists) {
65a206c0 174 ret = tcf_idr_create(tn, parm->index, est, a,
6f3dfb0d 175 &act_skbedit_ops, bind, true);
0190c1d4
VB
176 if (ret) {
177 tcf_idr_cleanup(tn, parm->index);
86062033 178 return ret;
0190c1d4 179 }
ca9b0e27 180
a85a970a 181 d = to_skbedit(*a);
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AD
182 ret = ACT_P_CREATED;
183 } else {
a85a970a 184 d = to_skbedit(*a);
4e8ddd7f
VB
185 if (!ovr) {
186 tcf_idr_release(*a, bind);
ca9b0e27 187 return -EEXIST;
4e8ddd7f 188 }
ca9b0e27
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189 }
190
c749cdda
DC
191 params_new = kzalloc(sizeof(*params_new), GFP_KERNEL);
192 if (unlikely(!params_new)) {
6191da98 193 tcf_idr_release(*a, bind);
c749cdda
DC
194 return -ENOMEM;
195 }
196
197 params_new->flags = flags;
ca9b0e27 198 if (flags & SKBEDIT_F_PRIORITY)
c749cdda 199 params_new->priority = *priority;
ca9b0e27 200 if (flags & SKBEDIT_F_QUEUE_MAPPING)
c749cdda 201 params_new->queue_mapping = *queue_mapping;
1c55d62e 202 if (flags & SKBEDIT_F_MARK)
c749cdda 203 params_new->mark = *mark;
ff202ee1 204 if (flags & SKBEDIT_F_PTYPE)
c749cdda 205 params_new->ptype = *ptype;
4fe77d82 206 /* default behaviour is to use all the bits */
c749cdda 207 params_new->mask = 0xffffffff;
4fe77d82 208 if (flags & SKBEDIT_F_MASK)
c749cdda 209 params_new->mask = *mask;
1c55d62e 210
6d7a8df6 211 spin_lock_bh(&d->tcf_lock);
ca9b0e27 212 d->tcf_action = parm->action;
6d7a8df6
VB
213 rcu_swap_protected(d->params, params_new,
214 lockdep_is_held(&d->tcf_lock));
215 spin_unlock_bh(&d->tcf_lock);
216 if (params_new)
217 kfree_rcu(params_new, rcu);
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AD
218
219 if (ret == ACT_P_CREATED)
65a206c0 220 tcf_idr_insert(tn, *a);
ca9b0e27
AD
221 return ret;
222}
223
cc7ec456
ED
224static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
225 int bind, int ref)
ca9b0e27
AD
226{
227 unsigned char *b = skb_tail_pointer(skb);
a85a970a 228 struct tcf_skbedit *d = to_skbedit(a);
c749cdda 229 struct tcf_skbedit_params *params;
1c40be12
ED
230 struct tc_skbedit opt = {
231 .index = d->tcf_index,
036bb443
VB
232 .refcnt = refcount_read(&d->tcf_refcnt) - ref,
233 .bindcnt = atomic_read(&d->tcf_bindcnt) - bind,
1c40be12 234 };
e7e3728b 235 u64 pure_flags = 0;
c749cdda
DC
236 struct tcf_t t;
237
6d7a8df6
VB
238 spin_lock_bh(&d->tcf_lock);
239 params = rcu_dereference_protected(d->params,
240 lockdep_is_held(&d->tcf_lock));
241 opt.action = d->tcf_action;
ca9b0e27 242
1b34ec43
DM
243 if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
244 goto nla_put_failure;
c749cdda
DC
245 if ((params->flags & SKBEDIT_F_PRIORITY) &&
246 nla_put_u32(skb, TCA_SKBEDIT_PRIORITY, params->priority))
1b34ec43 247 goto nla_put_failure;
c749cdda
DC
248 if ((params->flags & SKBEDIT_F_QUEUE_MAPPING) &&
249 nla_put_u16(skb, TCA_SKBEDIT_QUEUE_MAPPING, params->queue_mapping))
1b34ec43 250 goto nla_put_failure;
c749cdda
DC
251 if ((params->flags & SKBEDIT_F_MARK) &&
252 nla_put_u32(skb, TCA_SKBEDIT_MARK, params->mark))
1b34ec43 253 goto nla_put_failure;
c749cdda
DC
254 if ((params->flags & SKBEDIT_F_PTYPE) &&
255 nla_put_u16(skb, TCA_SKBEDIT_PTYPE, params->ptype))
ff202ee1 256 goto nla_put_failure;
c749cdda
DC
257 if ((params->flags & SKBEDIT_F_MASK) &&
258 nla_put_u32(skb, TCA_SKBEDIT_MASK, params->mask))
4fe77d82 259 goto nla_put_failure;
c749cdda 260 if (params->flags & SKBEDIT_F_INHERITDSFIELD)
e7e3728b
QF
261 pure_flags |= SKBEDIT_F_INHERITDSFIELD;
262 if (pure_flags != 0 &&
263 nla_put(skb, TCA_SKBEDIT_FLAGS, sizeof(pure_flags), &pure_flags))
264 goto nla_put_failure;
48d8ee16
JHS
265
266 tcf_tm_dump(&t, &d->tcf_tm);
9854518e 267 if (nla_put_64bit(skb, TCA_SKBEDIT_TM, sizeof(t), &t, TCA_SKBEDIT_PAD))
1b34ec43 268 goto nla_put_failure;
6d7a8df6
VB
269 spin_unlock_bh(&d->tcf_lock);
270
ca9b0e27
AD
271 return skb->len;
272
273nla_put_failure:
6d7a8df6 274 spin_unlock_bh(&d->tcf_lock);
ca9b0e27
AD
275 nlmsg_trim(skb, b);
276 return -1;
277}
278
c749cdda
DC
279static void tcf_skbedit_cleanup(struct tc_action *a)
280{
281 struct tcf_skbedit *d = to_skbedit(a);
282 struct tcf_skbedit_params *params;
283
284 params = rcu_dereference_protected(d->params, 1);
285 if (params)
286 kfree_rcu(params, rcu);
287}
288
ddf97ccd
WC
289static int tcf_skbedit_walker(struct net *net, struct sk_buff *skb,
290 struct netlink_callback *cb, int type,
41780105
AA
291 const struct tc_action_ops *ops,
292 struct netlink_ext_ack *extack)
ddf97ccd
WC
293{
294 struct tc_action_net *tn = net_generic(net, skbedit_net_id);
295
b3620145 296 return tcf_generic_walker(tn, skb, cb, type, ops, extack);
ddf97ccd
WC
297}
298
f061b48c 299static int tcf_skbedit_search(struct net *net, struct tc_action **a, u32 index)
ddf97ccd
WC
300{
301 struct tc_action_net *tn = net_generic(net, skbedit_net_id);
302
65a206c0 303 return tcf_idr_search(tn, a, index);
ddf97ccd
WC
304}
305
ca9b0e27
AD
306static struct tc_action_ops act_skbedit_ops = {
307 .kind = "skbedit",
eddd2cf1 308 .id = TCA_ID_SKBEDIT,
ca9b0e27 309 .owner = THIS_MODULE,
45da1dac 310 .act = tcf_skbedit_act,
ca9b0e27 311 .dump = tcf_skbedit_dump,
ca9b0e27 312 .init = tcf_skbedit_init,
c749cdda 313 .cleanup = tcf_skbedit_cleanup,
ddf97ccd
WC
314 .walk = tcf_skbedit_walker,
315 .lookup = tcf_skbedit_search,
a85a970a 316 .size = sizeof(struct tcf_skbedit),
ddf97ccd
WC
317};
318
319static __net_init int skbedit_init_net(struct net *net)
320{
321 struct tc_action_net *tn = net_generic(net, skbedit_net_id);
322
c7e460ce 323 return tc_action_net_init(tn, &act_skbedit_ops);
ddf97ccd
WC
324}
325
039af9c6 326static void __net_exit skbedit_exit_net(struct list_head *net_list)
ddf97ccd 327{
039af9c6 328 tc_action_net_exit(net_list, skbedit_net_id);
ddf97ccd
WC
329}
330
331static struct pernet_operations skbedit_net_ops = {
332 .init = skbedit_init_net,
039af9c6 333 .exit_batch = skbedit_exit_net,
ddf97ccd
WC
334 .id = &skbedit_net_id,
335 .size = sizeof(struct tc_action_net),
ca9b0e27
AD
336};
337
338MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
339MODULE_DESCRIPTION("SKB Editing");
340MODULE_LICENSE("GPL");
341
342static int __init skbedit_init_module(void)
343{
ddf97ccd 344 return tcf_register_action(&act_skbedit_ops, &skbedit_net_ops);
ca9b0e27
AD
345}
346
347static void __exit skbedit_cleanup_module(void)
348{
ddf97ccd 349 tcf_unregister_action(&act_skbedit_ops, &skbedit_net_ops);
ca9b0e27
AD
350}
351
352module_init(skbedit_init_module);
353module_exit(skbedit_cleanup_module);