Loading...
1/*
2 * net/sched/pedit.c Generic packet editor
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 *
9 * Authors: Jamal Hadi Salim (2002-4)
10 */
11
12#include <linux/types.h>
13#include <linux/kernel.h>
14#include <linux/string.h>
15#include <linux/errno.h>
16#include <linux/skbuff.h>
17#include <linux/rtnetlink.h>
18#include <linux/module.h>
19#include <linux/init.h>
20#include <linux/slab.h>
21#include <net/netlink.h>
22#include <net/pkt_sched.h>
23#include <linux/tc_act/tc_pedit.h>
24#include <net/tc_act/tc_pedit.h>
25
26#define PEDIT_TAB_MASK 15
27
28static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = {
29 [TCA_PEDIT_PARMS] = { .len = sizeof(struct tc_pedit) },
30};
31
32static int tcf_pedit_init(struct net *net, struct nlattr *nla,
33 struct nlattr *est, struct tc_action *a,
34 int ovr, int bind)
35{
36 struct nlattr *tb[TCA_PEDIT_MAX + 1];
37 struct tc_pedit *parm;
38 int ret = 0, err;
39 struct tcf_pedit *p;
40 struct tc_pedit_key *keys = NULL;
41 int ksize;
42
43 if (nla == NULL)
44 return -EINVAL;
45
46 err = nla_parse_nested(tb, TCA_PEDIT_MAX, nla, pedit_policy);
47 if (err < 0)
48 return err;
49
50 if (tb[TCA_PEDIT_PARMS] == NULL)
51 return -EINVAL;
52 parm = nla_data(tb[TCA_PEDIT_PARMS]);
53 ksize = parm->nkeys * sizeof(struct tc_pedit_key);
54 if (nla_len(tb[TCA_PEDIT_PARMS]) < sizeof(*parm) + ksize)
55 return -EINVAL;
56
57 if (!tcf_hash_check(parm->index, a, bind)) {
58 if (!parm->nkeys)
59 return -EINVAL;
60 ret = tcf_hash_create(parm->index, est, a, sizeof(*p), bind);
61 if (ret)
62 return ret;
63 p = to_pedit(a);
64 keys = kmalloc(ksize, GFP_KERNEL);
65 if (keys == NULL) {
66 tcf_hash_cleanup(a, est);
67 return -ENOMEM;
68 }
69 ret = ACT_P_CREATED;
70 } else {
71 p = to_pedit(a);
72 tcf_hash_release(a, bind);
73 if (bind)
74 return 0;
75 if (!ovr)
76 return -EEXIST;
77
78 if (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys) {
79 keys = kmalloc(ksize, GFP_KERNEL);
80 if (keys == NULL)
81 return -ENOMEM;
82 }
83 }
84
85 spin_lock_bh(&p->tcf_lock);
86 p->tcfp_flags = parm->flags;
87 p->tcf_action = parm->action;
88 if (keys) {
89 kfree(p->tcfp_keys);
90 p->tcfp_keys = keys;
91 p->tcfp_nkeys = parm->nkeys;
92 }
93 memcpy(p->tcfp_keys, parm->keys, ksize);
94 spin_unlock_bh(&p->tcf_lock);
95 if (ret == ACT_P_CREATED)
96 tcf_hash_insert(a);
97 return ret;
98}
99
100static void tcf_pedit_cleanup(struct tc_action *a, int bind)
101{
102 struct tcf_pedit *p = a->priv;
103 struct tc_pedit_key *keys = p->tcfp_keys;
104 kfree(keys);
105}
106
107static int tcf_pedit(struct sk_buff *skb, const struct tc_action *a,
108 struct tcf_result *res)
109{
110 struct tcf_pedit *p = a->priv;
111 int i, munged = 0;
112 unsigned int off;
113
114 if (skb_unclone(skb, GFP_ATOMIC))
115 return p->tcf_action;
116
117 off = skb_network_offset(skb);
118
119 spin_lock(&p->tcf_lock);
120
121 p->tcf_tm.lastuse = jiffies;
122
123 if (p->tcfp_nkeys > 0) {
124 struct tc_pedit_key *tkey = p->tcfp_keys;
125
126 for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
127 u32 *ptr, _data;
128 int offset = tkey->off;
129
130 if (tkey->offmask) {
131 char *d, _d;
132
133 d = skb_header_pointer(skb, off + tkey->at, 1,
134 &_d);
135 if (!d)
136 goto bad;
137 offset += (*d & tkey->offmask) >> tkey->shift;
138 }
139
140 if (offset % 4) {
141 pr_info("tc filter pedit"
142 " offset must be on 32 bit boundaries\n");
143 goto bad;
144 }
145 if (offset > 0 && offset > skb->len) {
146 pr_info("tc filter pedit"
147 " offset %d can't exceed pkt length %d\n",
148 offset, skb->len);
149 goto bad;
150 }
151
152 ptr = skb_header_pointer(skb, off + offset, 4, &_data);
153 if (!ptr)
154 goto bad;
155 /* just do it, baby */
156 *ptr = ((*ptr & tkey->mask) ^ tkey->val);
157 if (ptr == &_data)
158 skb_store_bits(skb, off + offset, ptr, 4);
159 munged++;
160 }
161
162 if (munged)
163 skb->tc_verd = SET_TC_MUNGED(skb->tc_verd);
164 goto done;
165 } else
166 WARN(1, "pedit BUG: index %d\n", p->tcf_index);
167
168bad:
169 p->tcf_qstats.overlimits++;
170done:
171 bstats_update(&p->tcf_bstats, skb);
172 spin_unlock(&p->tcf_lock);
173 return p->tcf_action;
174}
175
176static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,
177 int bind, int ref)
178{
179 unsigned char *b = skb_tail_pointer(skb);
180 struct tcf_pedit *p = a->priv;
181 struct tc_pedit *opt;
182 struct tcf_t t;
183 int s;
184
185 s = sizeof(*opt) + p->tcfp_nkeys * sizeof(struct tc_pedit_key);
186
187 /* netlink spinlocks held above us - must use ATOMIC */
188 opt = kzalloc(s, GFP_ATOMIC);
189 if (unlikely(!opt))
190 return -ENOBUFS;
191
192 memcpy(opt->keys, p->tcfp_keys,
193 p->tcfp_nkeys * sizeof(struct tc_pedit_key));
194 opt->index = p->tcf_index;
195 opt->nkeys = p->tcfp_nkeys;
196 opt->flags = p->tcfp_flags;
197 opt->action = p->tcf_action;
198 opt->refcnt = p->tcf_refcnt - ref;
199 opt->bindcnt = p->tcf_bindcnt - bind;
200
201 if (nla_put(skb, TCA_PEDIT_PARMS, s, opt))
202 goto nla_put_failure;
203 t.install = jiffies_to_clock_t(jiffies - p->tcf_tm.install);
204 t.lastuse = jiffies_to_clock_t(jiffies - p->tcf_tm.lastuse);
205 t.expires = jiffies_to_clock_t(p->tcf_tm.expires);
206 if (nla_put(skb, TCA_PEDIT_TM, sizeof(t), &t))
207 goto nla_put_failure;
208 kfree(opt);
209 return skb->len;
210
211nla_put_failure:
212 nlmsg_trim(skb, b);
213 kfree(opt);
214 return -1;
215}
216
217static struct tc_action_ops act_pedit_ops = {
218 .kind = "pedit",
219 .type = TCA_ACT_PEDIT,
220 .owner = THIS_MODULE,
221 .act = tcf_pedit,
222 .dump = tcf_pedit_dump,
223 .cleanup = tcf_pedit_cleanup,
224 .init = tcf_pedit_init,
225};
226
227MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
228MODULE_DESCRIPTION("Generic Packet Editor actions");
229MODULE_LICENSE("GPL");
230
231static int __init pedit_init_module(void)
232{
233 return tcf_register_action(&act_pedit_ops, PEDIT_TAB_MASK);
234}
235
236static void __exit pedit_cleanup_module(void)
237{
238 tcf_unregister_action(&act_pedit_ops);
239}
240
241module_init(pedit_init_module);
242module_exit(pedit_cleanup_module);
243
1/*
2 * net/sched/pedit.c Generic packet editor
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 *
9 * Authors: Jamal Hadi Salim (2002-4)
10 */
11
12#include <linux/types.h>
13#include <linux/kernel.h>
14#include <linux/string.h>
15#include <linux/errno.h>
16#include <linux/skbuff.h>
17#include <linux/rtnetlink.h>
18#include <linux/module.h>
19#include <linux/init.h>
20#include <linux/slab.h>
21#include <net/netlink.h>
22#include <net/pkt_sched.h>
23#include <linux/tc_act/tc_pedit.h>
24#include <net/tc_act/tc_pedit.h>
25
26#define PEDIT_TAB_MASK 15
27static struct tcf_common *tcf_pedit_ht[PEDIT_TAB_MASK + 1];
28static u32 pedit_idx_gen;
29static DEFINE_RWLOCK(pedit_lock);
30
31static struct tcf_hashinfo pedit_hash_info = {
32 .htab = tcf_pedit_ht,
33 .hmask = PEDIT_TAB_MASK,
34 .lock = &pedit_lock,
35};
36
37static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = {
38 [TCA_PEDIT_PARMS] = { .len = sizeof(struct tc_pedit) },
39};
40
41static int tcf_pedit_init(struct nlattr *nla, struct nlattr *est,
42 struct tc_action *a, int ovr, int bind)
43{
44 struct nlattr *tb[TCA_PEDIT_MAX + 1];
45 struct tc_pedit *parm;
46 int ret = 0, err;
47 struct tcf_pedit *p;
48 struct tcf_common *pc;
49 struct tc_pedit_key *keys = NULL;
50 int ksize;
51
52 if (nla == NULL)
53 return -EINVAL;
54
55 err = nla_parse_nested(tb, TCA_PEDIT_MAX, nla, pedit_policy);
56 if (err < 0)
57 return err;
58
59 if (tb[TCA_PEDIT_PARMS] == NULL)
60 return -EINVAL;
61 parm = nla_data(tb[TCA_PEDIT_PARMS]);
62 ksize = parm->nkeys * sizeof(struct tc_pedit_key);
63 if (nla_len(tb[TCA_PEDIT_PARMS]) < sizeof(*parm) + ksize)
64 return -EINVAL;
65
66 pc = tcf_hash_check(parm->index, a, bind, &pedit_hash_info);
67 if (!pc) {
68 if (!parm->nkeys)
69 return -EINVAL;
70 pc = tcf_hash_create(parm->index, est, a, sizeof(*p), bind,
71 &pedit_idx_gen, &pedit_hash_info);
72 if (IS_ERR(pc))
73 return PTR_ERR(pc);
74 p = to_pedit(pc);
75 keys = kmalloc(ksize, GFP_KERNEL);
76 if (keys == NULL) {
77 kfree(pc);
78 return -ENOMEM;
79 }
80 ret = ACT_P_CREATED;
81 } else {
82 p = to_pedit(pc);
83 if (!ovr) {
84 tcf_hash_release(pc, bind, &pedit_hash_info);
85 return -EEXIST;
86 }
87 if (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys) {
88 keys = kmalloc(ksize, GFP_KERNEL);
89 if (keys == NULL)
90 return -ENOMEM;
91 }
92 }
93
94 spin_lock_bh(&p->tcf_lock);
95 p->tcfp_flags = parm->flags;
96 p->tcf_action = parm->action;
97 if (keys) {
98 kfree(p->tcfp_keys);
99 p->tcfp_keys = keys;
100 p->tcfp_nkeys = parm->nkeys;
101 }
102 memcpy(p->tcfp_keys, parm->keys, ksize);
103 spin_unlock_bh(&p->tcf_lock);
104 if (ret == ACT_P_CREATED)
105 tcf_hash_insert(pc, &pedit_hash_info);
106 return ret;
107}
108
109static int tcf_pedit_cleanup(struct tc_action *a, int bind)
110{
111 struct tcf_pedit *p = a->priv;
112
113 if (p) {
114 struct tc_pedit_key *keys = p->tcfp_keys;
115 if (tcf_hash_release(&p->common, bind, &pedit_hash_info)) {
116 kfree(keys);
117 return 1;
118 }
119 }
120 return 0;
121}
122
123static int tcf_pedit(struct sk_buff *skb, const struct tc_action *a,
124 struct tcf_result *res)
125{
126 struct tcf_pedit *p = a->priv;
127 int i, munged = 0;
128 unsigned int off;
129
130 if (skb_cloned(skb) &&
131 pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
132 return p->tcf_action;
133
134 off = skb_network_offset(skb);
135
136 spin_lock(&p->tcf_lock);
137
138 p->tcf_tm.lastuse = jiffies;
139
140 if (p->tcfp_nkeys > 0) {
141 struct tc_pedit_key *tkey = p->tcfp_keys;
142
143 for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
144 u32 *ptr, _data;
145 int offset = tkey->off;
146
147 if (tkey->offmask) {
148 char *d, _d;
149
150 d = skb_header_pointer(skb, off + tkey->at, 1,
151 &_d);
152 if (!d)
153 goto bad;
154 offset += (*d & tkey->offmask) >> tkey->shift;
155 }
156
157 if (offset % 4) {
158 pr_info("tc filter pedit"
159 " offset must be on 32 bit boundaries\n");
160 goto bad;
161 }
162 if (offset > 0 && offset > skb->len) {
163 pr_info("tc filter pedit"
164 " offset %d can't exceed pkt length %d\n",
165 offset, skb->len);
166 goto bad;
167 }
168
169 ptr = skb_header_pointer(skb, off + offset, 4, &_data);
170 if (!ptr)
171 goto bad;
172 /* just do it, baby */
173 *ptr = ((*ptr & tkey->mask) ^ tkey->val);
174 if (ptr == &_data)
175 skb_store_bits(skb, off + offset, ptr, 4);
176 munged++;
177 }
178
179 if (munged)
180 skb->tc_verd = SET_TC_MUNGED(skb->tc_verd);
181 goto done;
182 } else
183 WARN(1, "pedit BUG: index %d\n", p->tcf_index);
184
185bad:
186 p->tcf_qstats.overlimits++;
187done:
188 bstats_update(&p->tcf_bstats, skb);
189 spin_unlock(&p->tcf_lock);
190 return p->tcf_action;
191}
192
193static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,
194 int bind, int ref)
195{
196 unsigned char *b = skb_tail_pointer(skb);
197 struct tcf_pedit *p = a->priv;
198 struct tc_pedit *opt;
199 struct tcf_t t;
200 int s;
201
202 s = sizeof(*opt) + p->tcfp_nkeys * sizeof(struct tc_pedit_key);
203
204 /* netlink spinlocks held above us - must use ATOMIC */
205 opt = kzalloc(s, GFP_ATOMIC);
206 if (unlikely(!opt))
207 return -ENOBUFS;
208
209 memcpy(opt->keys, p->tcfp_keys,
210 p->tcfp_nkeys * sizeof(struct tc_pedit_key));
211 opt->index = p->tcf_index;
212 opt->nkeys = p->tcfp_nkeys;
213 opt->flags = p->tcfp_flags;
214 opt->action = p->tcf_action;
215 opt->refcnt = p->tcf_refcnt - ref;
216 opt->bindcnt = p->tcf_bindcnt - bind;
217
218 NLA_PUT(skb, TCA_PEDIT_PARMS, s, opt);
219 t.install = jiffies_to_clock_t(jiffies - p->tcf_tm.install);
220 t.lastuse = jiffies_to_clock_t(jiffies - p->tcf_tm.lastuse);
221 t.expires = jiffies_to_clock_t(p->tcf_tm.expires);
222 NLA_PUT(skb, TCA_PEDIT_TM, sizeof(t), &t);
223 kfree(opt);
224 return skb->len;
225
226nla_put_failure:
227 nlmsg_trim(skb, b);
228 kfree(opt);
229 return -1;
230}
231
232static struct tc_action_ops act_pedit_ops = {
233 .kind = "pedit",
234 .hinfo = &pedit_hash_info,
235 .type = TCA_ACT_PEDIT,
236 .capab = TCA_CAP_NONE,
237 .owner = THIS_MODULE,
238 .act = tcf_pedit,
239 .dump = tcf_pedit_dump,
240 .cleanup = tcf_pedit_cleanup,
241 .lookup = tcf_hash_search,
242 .init = tcf_pedit_init,
243 .walk = tcf_generic_walker
244};
245
246MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
247MODULE_DESCRIPTION("Generic Packet Editor actions");
248MODULE_LICENSE("GPL");
249
250static int __init pedit_init_module(void)
251{
252 return tcf_register_action(&act_pedit_ops);
253}
254
255static void __exit pedit_cleanup_module(void)
256{
257 tcf_unregister_action(&act_pedit_ops);
258}
259
260module_init(pedit_init_module);
261module_exit(pedit_cleanup_module);
262