Commit | Line | Data |
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1da177e4 LT |
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 | ||
1da177e4 LT |
12 | #include <linux/types.h> |
13 | #include <linux/kernel.h> | |
1da177e4 | 14 | #include <linux/string.h> |
1da177e4 | 15 | #include <linux/errno.h> |
1da177e4 LT |
16 | #include <linux/skbuff.h> |
17 | #include <linux/rtnetlink.h> | |
18 | #include <linux/module.h> | |
19 | #include <linux/init.h> | |
5a0e3ad6 | 20 | #include <linux/slab.h> |
dc5fc579 | 21 | #include <net/netlink.h> |
1da177e4 LT |
22 | #include <net/pkt_sched.h> |
23 | #include <linux/tc_act/tc_pedit.h> | |
24 | #include <net/tc_act/tc_pedit.h> | |
25 | ||
e9ce1cd3 DM |
26 | #define PEDIT_TAB_MASK 15 |
27 | static struct tcf_common *tcf_pedit_ht[PEDIT_TAB_MASK + 1]; | |
28 | static u32 pedit_idx_gen; | |
1da177e4 LT |
29 | static DEFINE_RWLOCK(pedit_lock); |
30 | ||
e9ce1cd3 DM |
31 | static struct tcf_hashinfo pedit_hash_info = { |
32 | .htab = tcf_pedit_ht, | |
33 | .hmask = PEDIT_TAB_MASK, | |
34 | .lock = &pedit_lock, | |
35 | }; | |
1da177e4 | 36 | |
53b2bf3f | 37 | static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = { |
53f7e35f | 38 | [TCA_PEDIT_PARMS] = { .len = sizeof(struct tc_pedit) }, |
53b2bf3f PM |
39 | }; |
40 | ||
7ba699c6 | 41 | static int tcf_pedit_init(struct nlattr *nla, struct nlattr *est, |
e9ce1cd3 | 42 | struct tc_action *a, int ovr, int bind) |
1da177e4 | 43 | { |
7ba699c6 | 44 | struct nlattr *tb[TCA_PEDIT_MAX + 1]; |
1da177e4 | 45 | struct tc_pedit *parm; |
cee63723 | 46 | int ret = 0, err; |
1da177e4 | 47 | struct tcf_pedit *p; |
e9ce1cd3 | 48 | struct tcf_common *pc; |
1da177e4 LT |
49 | struct tc_pedit_key *keys = NULL; |
50 | int ksize; | |
51 | ||
cee63723 | 52 | if (nla == NULL) |
1da177e4 LT |
53 | return -EINVAL; |
54 | ||
53b2bf3f | 55 | err = nla_parse_nested(tb, TCA_PEDIT_MAX, nla, pedit_policy); |
cee63723 PM |
56 | if (err < 0) |
57 | return err; | |
58 | ||
53b2bf3f | 59 | if (tb[TCA_PEDIT_PARMS] == NULL) |
1da177e4 | 60 | return -EINVAL; |
7ba699c6 | 61 | parm = nla_data(tb[TCA_PEDIT_PARMS]); |
1da177e4 | 62 | ksize = parm->nkeys * sizeof(struct tc_pedit_key); |
7ba699c6 | 63 | if (nla_len(tb[TCA_PEDIT_PARMS]) < sizeof(*parm) + ksize) |
1da177e4 LT |
64 | return -EINVAL; |
65 | ||
e9ce1cd3 DM |
66 | pc = tcf_hash_check(parm->index, a, bind, &pedit_hash_info); |
67 | if (!pc) { | |
1da177e4 LT |
68 | if (!parm->nkeys) |
69 | return -EINVAL; | |
e9ce1cd3 DM |
70 | pc = tcf_hash_create(parm->index, est, a, sizeof(*p), bind, |
71 | &pedit_idx_gen, &pedit_hash_info); | |
0e991ec6 SH |
72 | if (IS_ERR(pc)) |
73 | return PTR_ERR(pc); | |
e9ce1cd3 | 74 | p = to_pedit(pc); |
1da177e4 LT |
75 | keys = kmalloc(ksize, GFP_KERNEL); |
76 | if (keys == NULL) { | |
e9ce1cd3 | 77 | kfree(pc); |
1da177e4 LT |
78 | return -ENOMEM; |
79 | } | |
80 | ret = ACT_P_CREATED; | |
81 | } else { | |
e9ce1cd3 | 82 | p = to_pedit(pc); |
1da177e4 | 83 | if (!ovr) { |
e9ce1cd3 | 84 | tcf_hash_release(pc, bind, &pedit_hash_info); |
1da177e4 LT |
85 | return -EEXIST; |
86 | } | |
e9ce1cd3 | 87 | if (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys) { |
1da177e4 LT |
88 | keys = kmalloc(ksize, GFP_KERNEL); |
89 | if (keys == NULL) | |
90 | return -ENOMEM; | |
91 | } | |
92 | } | |
93 | ||
e9ce1cd3 DM |
94 | spin_lock_bh(&p->tcf_lock); |
95 | p->tcfp_flags = parm->flags; | |
96 | p->tcf_action = parm->action; | |
1da177e4 | 97 | if (keys) { |
e9ce1cd3 DM |
98 | kfree(p->tcfp_keys); |
99 | p->tcfp_keys = keys; | |
100 | p->tcfp_nkeys = parm->nkeys; | |
1da177e4 | 101 | } |
e9ce1cd3 DM |
102 | memcpy(p->tcfp_keys, parm->keys, ksize); |
103 | spin_unlock_bh(&p->tcf_lock); | |
1da177e4 | 104 | if (ret == ACT_P_CREATED) |
e9ce1cd3 | 105 | tcf_hash_insert(pc, &pedit_hash_info); |
1da177e4 LT |
106 | return ret; |
107 | } | |
108 | ||
e9ce1cd3 | 109 | static int tcf_pedit_cleanup(struct tc_action *a, int bind) |
1da177e4 | 110 | { |
e9ce1cd3 | 111 | struct tcf_pedit *p = a->priv; |
1da177e4 | 112 | |
e9ce1cd3 DM |
113 | if (p) { |
114 | struct tc_pedit_key *keys = p->tcfp_keys; | |
115 | if (tcf_hash_release(&p->common, bind, &pedit_hash_info)) { | |
1da177e4 LT |
116 | kfree(keys); |
117 | return 1; | |
118 | } | |
119 | } | |
120 | return 0; | |
121 | } | |
122 | ||
e9ce1cd3 DM |
123 | static int tcf_pedit(struct sk_buff *skb, struct tc_action *a, |
124 | struct tcf_result *res) | |
1da177e4 | 125 | { |
e9ce1cd3 | 126 | struct tcf_pedit *p = a->priv; |
1da177e4 | 127 | int i, munged = 0; |
db2c2417 | 128 | unsigned int off; |
1da177e4 | 129 | |
9dacaf17 | 130 | if (skb_cloned(skb)) { |
1da177e4 | 131 | if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) { |
e9ce1cd3 | 132 | return p->tcf_action; |
1da177e4 LT |
133 | } |
134 | } | |
135 | ||
db2c2417 | 136 | off = skb_network_offset(skb); |
1da177e4 | 137 | |
e9ce1cd3 | 138 | spin_lock(&p->tcf_lock); |
1da177e4 | 139 | |
e9ce1cd3 | 140 | p->tcf_tm.lastuse = jiffies; |
1da177e4 | 141 | |
e9ce1cd3 DM |
142 | if (p->tcfp_nkeys > 0) { |
143 | struct tc_pedit_key *tkey = p->tcfp_keys; | |
1da177e4 | 144 | |
e9ce1cd3 | 145 | for (i = p->tcfp_nkeys; i > 0; i--, tkey++) { |
db2c2417 | 146 | u32 *ptr, _data; |
1da177e4 LT |
147 | int offset = tkey->off; |
148 | ||
149 | if (tkey->offmask) { | |
db2c2417 CG |
150 | char *d, _d; |
151 | ||
152 | d = skb_header_pointer(skb, off + tkey->at, 1, | |
153 | &_d); | |
154 | if (!d) | |
1da177e4 | 155 | goto bad; |
db2c2417 | 156 | offset += (*d & tkey->offmask) >> tkey->shift; |
1da177e4 LT |
157 | } |
158 | ||
159 | if (offset % 4) { | |
6ff9c364 | 160 | pr_info("tc filter pedit" |
161 | " offset must be on 32 bit boundaries\n"); | |
1da177e4 LT |
162 | goto bad; |
163 | } | |
75202e76 | 164 | if (offset > 0 && offset > skb->len) { |
6ff9c364 | 165 | pr_info("tc filter pedit" |
166 | " offset %d cant exceed pkt length %d\n", | |
1da177e4 LT |
167 | offset, skb->len); |
168 | goto bad; | |
169 | } | |
170 | ||
db2c2417 CG |
171 | ptr = skb_header_pointer(skb, off + offset, 4, &_data); |
172 | if (!ptr) | |
173 | goto bad; | |
1da177e4 LT |
174 | /* just do it, baby */ |
175 | *ptr = ((*ptr & tkey->mask) ^ tkey->val); | |
db2c2417 CG |
176 | if (ptr == &_data) |
177 | skb_store_bits(skb, off + offset, ptr, 4); | |
1da177e4 LT |
178 | munged++; |
179 | } | |
10297b99 | 180 | |
1da177e4 LT |
181 | if (munged) |
182 | skb->tc_verd = SET_TC_MUNGED(skb->tc_verd); | |
183 | goto done; | |
6ff9c364 | 184 | } else |
185 | WARN(1, "pedit BUG: index %d\n", p->tcf_index); | |
1da177e4 LT |
186 | |
187 | bad: | |
e9ce1cd3 | 188 | p->tcf_qstats.overlimits++; |
1da177e4 | 189 | done: |
0abf77e5 | 190 | p->tcf_bstats.bytes += qdisc_pkt_len(skb); |
e9ce1cd3 DM |
191 | p->tcf_bstats.packets++; |
192 | spin_unlock(&p->tcf_lock); | |
193 | return p->tcf_action; | |
1da177e4 LT |
194 | } |
195 | ||
e9ce1cd3 DM |
196 | static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a, |
197 | int bind, int ref) | |
1da177e4 | 198 | { |
27a884dc | 199 | unsigned char *b = skb_tail_pointer(skb); |
e9ce1cd3 | 200 | struct tcf_pedit *p = a->priv; |
1da177e4 | 201 | struct tc_pedit *opt; |
1da177e4 | 202 | struct tcf_t t; |
10297b99 YH |
203 | int s; |
204 | ||
e9ce1cd3 | 205 | s = sizeof(*opt) + p->tcfp_nkeys * sizeof(struct tc_pedit_key); |
1da177e4 LT |
206 | |
207 | /* netlink spinlocks held above us - must use ATOMIC */ | |
0da974f4 | 208 | opt = kzalloc(s, GFP_ATOMIC); |
e9ce1cd3 | 209 | if (unlikely(!opt)) |
1da177e4 | 210 | return -ENOBUFS; |
1da177e4 | 211 | |
e9ce1cd3 DM |
212 | memcpy(opt->keys, p->tcfp_keys, |
213 | p->tcfp_nkeys * sizeof(struct tc_pedit_key)); | |
214 | opt->index = p->tcf_index; | |
215 | opt->nkeys = p->tcfp_nkeys; | |
216 | opt->flags = p->tcfp_flags; | |
217 | opt->action = p->tcf_action; | |
218 | opt->refcnt = p->tcf_refcnt - ref; | |
219 | opt->bindcnt = p->tcf_bindcnt - bind; | |
1da177e4 | 220 | |
7ba699c6 | 221 | NLA_PUT(skb, TCA_PEDIT_PARMS, s, opt); |
e9ce1cd3 DM |
222 | t.install = jiffies_to_clock_t(jiffies - p->tcf_tm.install); |
223 | t.lastuse = jiffies_to_clock_t(jiffies - p->tcf_tm.lastuse); | |
224 | t.expires = jiffies_to_clock_t(p->tcf_tm.expires); | |
7ba699c6 | 225 | NLA_PUT(skb, TCA_PEDIT_TM, sizeof(t), &t); |
541673c8 | 226 | kfree(opt); |
1da177e4 LT |
227 | return skb->len; |
228 | ||
7ba699c6 | 229 | nla_put_failure: |
dc5fc579 | 230 | nlmsg_trim(skb, b); |
541673c8 | 231 | kfree(opt); |
1da177e4 LT |
232 | return -1; |
233 | } | |
234 | ||
e9ce1cd3 | 235 | static struct tc_action_ops act_pedit_ops = { |
1da177e4 | 236 | .kind = "pedit", |
e9ce1cd3 | 237 | .hinfo = &pedit_hash_info, |
1da177e4 LT |
238 | .type = TCA_ACT_PEDIT, |
239 | .capab = TCA_CAP_NONE, | |
240 | .owner = THIS_MODULE, | |
241 | .act = tcf_pedit, | |
242 | .dump = tcf_pedit_dump, | |
243 | .cleanup = tcf_pedit_cleanup, | |
244 | .lookup = tcf_hash_search, | |
245 | .init = tcf_pedit_init, | |
246 | .walk = tcf_generic_walker | |
247 | }; | |
248 | ||
249 | MODULE_AUTHOR("Jamal Hadi Salim(2002-4)"); | |
250 | MODULE_DESCRIPTION("Generic Packet Editor actions"); | |
251 | MODULE_LICENSE("GPL"); | |
252 | ||
e9ce1cd3 | 253 | static int __init pedit_init_module(void) |
1da177e4 LT |
254 | { |
255 | return tcf_register_action(&act_pedit_ops); | |
256 | } | |
257 | ||
e9ce1cd3 | 258 | static void __exit pedit_cleanup_module(void) |
1da177e4 LT |
259 | { |
260 | tcf_unregister_action(&act_pedit_ops); | |
261 | } | |
262 | ||
263 | module_init(pedit_init_module); | |
264 | module_exit(pedit_cleanup_module); | |
265 |