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6#include <linux/module.h>
7#include <linux/init.h>
8#include <linux/slab.h>
9#include <linux/types.h>
10#include <linux/string.h>
11#include <linux/errno.h>
12#include <linux/skbuff.h>
13#include <linux/rtnetlink.h>
14#include <linux/bitops.h>
15#include <net/pkt_sched.h>
16#include <net/dsfield.h>
17#include <net/inet_ecn.h>
18#include <asm/byteorder.h>
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36#define NO_DEFAULT_INDEX (1 << 16)
37
38struct dsmark_qdisc_data {
39 struct Qdisc *q;
40 struct tcf_proto __rcu *filter_list;
41 u8 *mask;
42 u8 *value;
43 u16 indices;
44 u32 default_index;
45 int set_tc_index;
46};
47
48static inline int dsmark_valid_index(struct dsmark_qdisc_data *p, u16 index)
49{
50 return index <= p->indices && index > 0;
51}
52
53
54
55static int dsmark_graft(struct Qdisc *sch, unsigned long arg,
56 struct Qdisc *new, struct Qdisc **old)
57{
58 struct dsmark_qdisc_data *p = qdisc_priv(sch);
59
60 pr_debug("%s(sch %p,[qdisc %p],new %p,old %p)\n",
61 __func__, sch, p, new, old);
62
63 if (new == NULL) {
64 new = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
65 sch->handle);
66 if (new == NULL)
67 new = &noop_qdisc;
68 }
69
70 sch_tree_lock(sch);
71 *old = p->q;
72 p->q = new;
73 qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
74 qdisc_reset(*old);
75 sch_tree_unlock(sch);
76
77 return 0;
78}
79
80static struct Qdisc *dsmark_leaf(struct Qdisc *sch, unsigned long arg)
81{
82 struct dsmark_qdisc_data *p = qdisc_priv(sch);
83 return p->q;
84}
85
86static unsigned long dsmark_get(struct Qdisc *sch, u32 classid)
87{
88 pr_debug("%s(sch %p,[qdisc %p],classid %x)\n",
89 __func__, sch, qdisc_priv(sch), classid);
90
91 return TC_H_MIN(classid) + 1;
92}
93
94static unsigned long dsmark_bind_filter(struct Qdisc *sch,
95 unsigned long parent, u32 classid)
96{
97 return dsmark_get(sch, classid);
98}
99
100static void dsmark_put(struct Qdisc *sch, unsigned long cl)
101{
102}
103
104static const struct nla_policy dsmark_policy[TCA_DSMARK_MAX + 1] = {
105 [TCA_DSMARK_INDICES] = { .type = NLA_U16 },
106 [TCA_DSMARK_DEFAULT_INDEX] = { .type = NLA_U16 },
107 [TCA_DSMARK_SET_TC_INDEX] = { .type = NLA_FLAG },
108 [TCA_DSMARK_MASK] = { .type = NLA_U8 },
109 [TCA_DSMARK_VALUE] = { .type = NLA_U8 },
110};
111
112static int dsmark_change(struct Qdisc *sch, u32 classid, u32 parent,
113 struct nlattr **tca, unsigned long *arg)
114{
115 struct dsmark_qdisc_data *p = qdisc_priv(sch);
116 struct nlattr *opt = tca[TCA_OPTIONS];
117 struct nlattr *tb[TCA_DSMARK_MAX + 1];
118 int err = -EINVAL;
119 u8 mask = 0;
120
121 pr_debug("%s(sch %p,[qdisc %p],classid %x,parent %x), arg 0x%lx\n",
122 __func__, sch, p, classid, parent, *arg);
123
124 if (!dsmark_valid_index(p, *arg)) {
125 err = -ENOENT;
126 goto errout;
127 }
128
129 if (!opt)
130 goto errout;
131
132 err = nla_parse_nested(tb, TCA_DSMARK_MAX, opt, dsmark_policy);
133 if (err < 0)
134 goto errout;
135
136 if (tb[TCA_DSMARK_MASK])
137 mask = nla_get_u8(tb[TCA_DSMARK_MASK]);
138
139 if (tb[TCA_DSMARK_VALUE])
140 p->value[*arg - 1] = nla_get_u8(tb[TCA_DSMARK_VALUE]);
141
142 if (tb[TCA_DSMARK_MASK])
143 p->mask[*arg - 1] = mask;
144
145 err = 0;
146
147errout:
148 return err;
149}
150
151static int dsmark_delete(struct Qdisc *sch, unsigned long arg)
152{
153 struct dsmark_qdisc_data *p = qdisc_priv(sch);
154
155 if (!dsmark_valid_index(p, arg))
156 return -EINVAL;
157
158 p->mask[arg - 1] = 0xff;
159 p->value[arg - 1] = 0;
160
161 return 0;
162}
163
164static void dsmark_walk(struct Qdisc *sch, struct qdisc_walker *walker)
165{
166 struct dsmark_qdisc_data *p = qdisc_priv(sch);
167 int i;
168
169 pr_debug("%s(sch %p,[qdisc %p],walker %p)\n",
170 __func__, sch, p, walker);
171
172 if (walker->stop)
173 return;
174
175 for (i = 0; i < p->indices; i++) {
176 if (p->mask[i] == 0xff && !p->value[i])
177 goto ignore;
178 if (walker->count >= walker->skip) {
179 if (walker->fn(sch, i + 1, walker) < 0) {
180 walker->stop = 1;
181 break;
182 }
183 }
184ignore:
185 walker->count++;
186 }
187}
188
189static inline struct tcf_proto __rcu **dsmark_find_tcf(struct Qdisc *sch,
190 unsigned long cl)
191{
192 struct dsmark_qdisc_data *p = qdisc_priv(sch);
193 return &p->filter_list;
194}
195
196
197
198static int dsmark_enqueue(struct sk_buff *skb, struct Qdisc *sch)
199{
200 struct dsmark_qdisc_data *p = qdisc_priv(sch);
201 int err;
202
203 pr_debug("%s(skb %p,sch %p,[qdisc %p])\n", __func__, skb, sch, p);
204
205 if (p->set_tc_index) {
206 switch (tc_skb_protocol(skb)) {
207 case htons(ETH_P_IP):
208 if (skb_cow_head(skb, sizeof(struct iphdr)))
209 goto drop;
210
211 skb->tc_index = ipv4_get_dsfield(ip_hdr(skb))
212 & ~INET_ECN_MASK;
213 break;
214
215 case htons(ETH_P_IPV6):
216 if (skb_cow_head(skb, sizeof(struct ipv6hdr)))
217 goto drop;
218
219 skb->tc_index = ipv6_get_dsfield(ipv6_hdr(skb))
220 & ~INET_ECN_MASK;
221 break;
222 default:
223 skb->tc_index = 0;
224 break;
225 }
226 }
227
228 if (TC_H_MAJ(skb->priority) == sch->handle)
229 skb->tc_index = TC_H_MIN(skb->priority);
230 else {
231 struct tcf_result res;
232 struct tcf_proto *fl = rcu_dereference_bh(p->filter_list);
233 int result = tc_classify(skb, fl, &res);
234
235 pr_debug("result %d class 0x%04x\n", result, res.classid);
236
237 switch (result) {
238#ifdef CONFIG_NET_CLS_ACT
239 case TC_ACT_QUEUED:
240 case TC_ACT_STOLEN:
241 kfree_skb(skb);
242 return NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
243
244 case TC_ACT_SHOT:
245 goto drop;
246#endif
247 case TC_ACT_OK:
248 skb->tc_index = TC_H_MIN(res.classid);
249 break;
250
251 default:
252 if (p->default_index != NO_DEFAULT_INDEX)
253 skb->tc_index = p->default_index;
254 break;
255 }
256 }
257
258 err = qdisc_enqueue(skb, p->q);
259 if (err != NET_XMIT_SUCCESS) {
260 if (net_xmit_drop_count(err))
261 qdisc_qstats_drop(sch);
262 return err;
263 }
264
265 sch->q.qlen++;
266
267 return NET_XMIT_SUCCESS;
268
269drop:
270 qdisc_drop(skb, sch);
271 return NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
272}
273
274static struct sk_buff *dsmark_dequeue(struct Qdisc *sch)
275{
276 struct dsmark_qdisc_data *p = qdisc_priv(sch);
277 struct sk_buff *skb;
278 u32 index;
279
280 pr_debug("%s(sch %p,[qdisc %p])\n", __func__, sch, p);
281
282 skb = p->q->ops->dequeue(p->q);
283 if (skb == NULL)
284 return NULL;
285
286 qdisc_bstats_update(sch, skb);
287 sch->q.qlen--;
288
289 index = skb->tc_index & (p->indices - 1);
290 pr_debug("index %d->%d\n", skb->tc_index, index);
291
292 switch (tc_skb_protocol(skb)) {
293 case htons(ETH_P_IP):
294 ipv4_change_dsfield(ip_hdr(skb), p->mask[index],
295 p->value[index]);
296 break;
297 case htons(ETH_P_IPV6):
298 ipv6_change_dsfield(ipv6_hdr(skb), p->mask[index],
299 p->value[index]);
300 break;
301 default:
302
303
304
305
306
307 if (p->mask[index] != 0xff || p->value[index])
308 pr_warn("%s: unsupported protocol %d\n",
309 __func__, ntohs(tc_skb_protocol(skb)));
310 break;
311 }
312
313 return skb;
314}
315
316static struct sk_buff *dsmark_peek(struct Qdisc *sch)
317{
318 struct dsmark_qdisc_data *p = qdisc_priv(sch);
319
320 pr_debug("%s(sch %p,[qdisc %p])\n", __func__, sch, p);
321
322 return p->q->ops->peek(p->q);
323}
324
325static unsigned int dsmark_drop(struct Qdisc *sch)
326{
327 struct dsmark_qdisc_data *p = qdisc_priv(sch);
328 unsigned int len;
329
330 pr_debug("%s(sch %p,[qdisc %p])\n", __func__, sch, p);
331
332 if (p->q->ops->drop == NULL)
333 return 0;
334
335 len = p->q->ops->drop(p->q);
336 if (len)
337 sch->q.qlen--;
338
339 return len;
340}
341
342static int dsmark_init(struct Qdisc *sch, struct nlattr *opt)
343{
344 struct dsmark_qdisc_data *p = qdisc_priv(sch);
345 struct nlattr *tb[TCA_DSMARK_MAX + 1];
346 int err = -EINVAL;
347 u32 default_index = NO_DEFAULT_INDEX;
348 u16 indices;
349 u8 *mask;
350
351 pr_debug("%s(sch %p,[qdisc %p],opt %p)\n", __func__, sch, p, opt);
352
353 if (!opt)
354 goto errout;
355
356 err = nla_parse_nested(tb, TCA_DSMARK_MAX, opt, dsmark_policy);
357 if (err < 0)
358 goto errout;
359
360 err = -EINVAL;
361 indices = nla_get_u16(tb[TCA_DSMARK_INDICES]);
362
363 if (hweight32(indices) != 1)
364 goto errout;
365
366 if (tb[TCA_DSMARK_DEFAULT_INDEX])
367 default_index = nla_get_u16(tb[TCA_DSMARK_DEFAULT_INDEX]);
368
369 mask = kmalloc(indices * 2, GFP_KERNEL);
370 if (mask == NULL) {
371 err = -ENOMEM;
372 goto errout;
373 }
374
375 p->mask = mask;
376 memset(p->mask, 0xff, indices);
377
378 p->value = p->mask + indices;
379 memset(p->value, 0, indices);
380
381 p->indices = indices;
382 p->default_index = default_index;
383 p->set_tc_index = nla_get_flag(tb[TCA_DSMARK_SET_TC_INDEX]);
384
385 p->q = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops, sch->handle);
386 if (p->q == NULL)
387 p->q = &noop_qdisc;
388
389 pr_debug("%s: qdisc %p\n", __func__, p->q);
390
391 err = 0;
392errout:
393 return err;
394}
395
396static void dsmark_reset(struct Qdisc *sch)
397{
398 struct dsmark_qdisc_data *p = qdisc_priv(sch);
399
400 pr_debug("%s(sch %p,[qdisc %p])\n", __func__, sch, p);
401 qdisc_reset(p->q);
402 sch->q.qlen = 0;
403}
404
405static void dsmark_destroy(struct Qdisc *sch)
406{
407 struct dsmark_qdisc_data *p = qdisc_priv(sch);
408
409 pr_debug("%s(sch %p,[qdisc %p])\n", __func__, sch, p);
410
411 tcf_destroy_chain(&p->filter_list);
412 qdisc_destroy(p->q);
413 kfree(p->mask);
414}
415
416static int dsmark_dump_class(struct Qdisc *sch, unsigned long cl,
417 struct sk_buff *skb, struct tcmsg *tcm)
418{
419 struct dsmark_qdisc_data *p = qdisc_priv(sch);
420 struct nlattr *opts = NULL;
421
422 pr_debug("%s(sch %p,[qdisc %p],class %ld\n", __func__, sch, p, cl);
423
424 if (!dsmark_valid_index(p, cl))
425 return -EINVAL;
426
427 tcm->tcm_handle = TC_H_MAKE(TC_H_MAJ(sch->handle), cl - 1);
428 tcm->tcm_info = p->q->handle;
429
430 opts = nla_nest_start(skb, TCA_OPTIONS);
431 if (opts == NULL)
432 goto nla_put_failure;
433 if (nla_put_u8(skb, TCA_DSMARK_MASK, p->mask[cl - 1]) ||
434 nla_put_u8(skb, TCA_DSMARK_VALUE, p->value[cl - 1]))
435 goto nla_put_failure;
436
437 return nla_nest_end(skb, opts);
438
439nla_put_failure:
440 nla_nest_cancel(skb, opts);
441 return -EMSGSIZE;
442}
443
444static int dsmark_dump(struct Qdisc *sch, struct sk_buff *skb)
445{
446 struct dsmark_qdisc_data *p = qdisc_priv(sch);
447 struct nlattr *opts = NULL;
448
449 opts = nla_nest_start(skb, TCA_OPTIONS);
450 if (opts == NULL)
451 goto nla_put_failure;
452 if (nla_put_u16(skb, TCA_DSMARK_INDICES, p->indices))
453 goto nla_put_failure;
454
455 if (p->default_index != NO_DEFAULT_INDEX &&
456 nla_put_u16(skb, TCA_DSMARK_DEFAULT_INDEX, p->default_index))
457 goto nla_put_failure;
458
459 if (p->set_tc_index &&
460 nla_put_flag(skb, TCA_DSMARK_SET_TC_INDEX))
461 goto nla_put_failure;
462
463 return nla_nest_end(skb, opts);
464
465nla_put_failure:
466 nla_nest_cancel(skb, opts);
467 return -EMSGSIZE;
468}
469
470static const struct Qdisc_class_ops dsmark_class_ops = {
471 .graft = dsmark_graft,
472 .leaf = dsmark_leaf,
473 .get = dsmark_get,
474 .put = dsmark_put,
475 .change = dsmark_change,
476 .delete = dsmark_delete,
477 .walk = dsmark_walk,
478 .tcf_chain = dsmark_find_tcf,
479 .bind_tcf = dsmark_bind_filter,
480 .unbind_tcf = dsmark_put,
481 .dump = dsmark_dump_class,
482};
483
484static struct Qdisc_ops dsmark_qdisc_ops __read_mostly = {
485 .next = NULL,
486 .cl_ops = &dsmark_class_ops,
487 .id = "dsmark",
488 .priv_size = sizeof(struct dsmark_qdisc_data),
489 .enqueue = dsmark_enqueue,
490 .dequeue = dsmark_dequeue,
491 .peek = dsmark_peek,
492 .drop = dsmark_drop,
493 .init = dsmark_init,
494 .reset = dsmark_reset,
495 .destroy = dsmark_destroy,
496 .change = NULL,
497 .dump = dsmark_dump,
498 .owner = THIS_MODULE,
499};
500
501static int __init dsmark_module_init(void)
502{
503 return register_qdisc(&dsmark_qdisc_ops);
504}
505
506static void __exit dsmark_module_exit(void)
507{
508 unregister_qdisc(&dsmark_qdisc_ops);
509}
510
511module_init(dsmark_module_init)
512module_exit(dsmark_module_exit)
513
514MODULE_LICENSE("GPL");
515