File: /usr/src/linux/net/sched/sch_ingress.c
1 /* net/sched/sch_ingress.c - Ingress qdisc
2 * This program is free software; you can redistribute it and/or
3 * modify it under the terms of the GNU General Public License
4 * as published by the Free Software Foundation; either version
5 * 2 of the License, or (at your option) any later version.
6 *
7 * Authors: Jamal Hadi Salim 1999
8 */
9
10 #include <linux/config.h>
11 #include <linux/module.h>
12 #include <linux/types.h>
13 #include <linux/skbuff.h>
14 #include <linux/netdevice.h>
15 #include <linux/rtnetlink.h>
16 #include <linux/netfilter_ipv4.h>
17 #include <linux/netfilter.h>
18 #include <net/pkt_sched.h>
19 #include <asm/byteorder.h>
20 #include <asm/uaccess.h>
21 #include <asm/smp.h>
22 #include <linux/kmod.h>
23 #include <linux/stat.h>
24 #include <linux/interrupt.h>
25 #include <linux/list.h>
26
27
28 #undef DEBUG_INGRESS
29
30 #ifdef DEBUG_INGRESS /* control */
31 #define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
32 #else
33 #define DPRINTK(format,args...)
34 #endif
35
36 #if 0 /* data */
37 #define D2PRINTK(format,args...) printk(KERN_DEBUG format,##args)
38 #else
39 #define D2PRINTK(format,args...)
40 #endif
41
42
43 #define PRIV(sch) ((struct ingress_qdisc_data *) (sch)->data)
44
45
46
47 struct ingress_qdisc_data {
48 struct Qdisc *q;
49 struct tcf_proto *filter_list;
50 };
51
52
53 /* ------------------------- Class/flow operations ------------------------- */
54
55
56 static int ingress_graft(struct Qdisc *sch,unsigned long arg,
57 struct Qdisc *new,struct Qdisc **old)
58 {
59 #ifdef DEBUG_INGRESS
60 struct ingress_qdisc_data *p = PRIV(sch);
61 #endif
62
63 DPRINTK("ingress_graft(sch %p,[qdisc %p],new %p,old %p)\n",
64 sch, p, new, old);
65 DPRINTK("\n ingress_graft: You cannot add qdiscs to classes");
66 return 1;
67 }
68
69
70 static struct Qdisc *ingress_leaf(struct Qdisc *sch, unsigned long arg)
71 {
72 return NULL;
73 }
74
75
76 static unsigned long ingress_get(struct Qdisc *sch,u32 classid)
77 {
78 #ifdef DEBUG_INGRESS
79 struct ingress_qdisc_data *p = PRIV(sch);
80 #endif
81 DPRINTK("ingress_get(sch %p,[qdisc %p],classid %x)\n", sch, p, classid);
82 return TC_H_MIN(classid) + 1;
83 }
84
85
86 static unsigned long ingress_bind_filter(struct Qdisc *sch,
87 unsigned long parent, u32 classid)
88 {
89 return ingress_get(sch, classid);
90 }
91
92
93 static void ingress_put(struct Qdisc *sch, unsigned long cl)
94 {
95 }
96
97
98 static int ingress_change(struct Qdisc *sch, u32 classid, u32 parent,
99 struct rtattr **tca, unsigned long *arg)
100 {
101 #ifdef DEBUG_INGRESS
102 struct ingress_qdisc_data *p = PRIV(sch);
103 #endif
104 DPRINTK("ingress_change(sch %p,[qdisc %p],classid %x,parent %x),"
105 "arg 0x%lx\n", sch, p, classid, parent, *arg);
106 DPRINTK("No effect. sch_ingress doesnt maintain classes at the moment");
107 return 0;
108 }
109
110
111
112 static void ingress_walk(struct Qdisc *sch,struct qdisc_walker *walker)
113 {
114 #ifdef DEBUG_INGRESS
115 struct ingress_qdisc_data *p = PRIV(sch);
116 #endif
117 DPRINTK("ingress_walk(sch %p,[qdisc %p],walker %p)\n", sch, p, walker);
118 DPRINTK("No effect. sch_ingress doesnt maintain classes at the moment");
119 }
120
121
122 static struct tcf_proto **ingress_find_tcf(struct Qdisc *sch,unsigned long cl)
123 {
124 struct ingress_qdisc_data *p = PRIV(sch);
125
126 return &p->filter_list;
127 }
128
129
130 /* --------------------------- Qdisc operations ---------------------------- */
131
132
133 static int ingress_enqueue(struct sk_buff *skb,struct Qdisc *sch)
134 {
135 struct ingress_qdisc_data *p = PRIV(sch);
136 struct tcf_result res;
137 int result;
138
139 D2PRINTK("ingress_enqueue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
140 result = tc_classify(skb, p->filter_list, &res);
141 D2PRINTK("result %d class 0x%04x\n", result, res.classid);
142 /*
143 * Unlike normal "enqueue" functions, ingress_enqueue returns a
144 * firewall FW_* code.
145 */
146 switch (result) {
147 #ifdef CONFIG_NET_CLS_POLICE
148 case TC_POLICE_SHOT:
149 result = NF_DROP;
150 break;
151 case TC_POLICE_RECLASSIFY: /* DSCP remarking here ? */
152 case TC_POLICE_OK:
153 case TC_POLICE_UNSPEC:
154 default:
155 result = NF_ACCEPT;
156 break;
157 #endif
158 };
159
160 skb->tc_index = TC_H_MIN(res.classid);
161 return result;
162 }
163
164
165 static struct sk_buff *ingress_dequeue(struct Qdisc *sch)
166 {
167 /*
168 struct ingress_qdisc_data *p = PRIV(sch);
169 D2PRINTK("ingress_dequeue(sch %p,[qdisc %p])\n",sch,PRIV(p));
170 */
171 return NULL;
172 }
173
174
175 static int ingress_requeue(struct sk_buff *skb,struct Qdisc *sch)
176 {
177 /*
178 struct ingress_qdisc_data *p = PRIV(sch);
179 D2PRINTK("ingress_requeue(skb %p,sch %p,[qdisc %p])\n",skb,sch,PRIV(p));
180 */
181 return 0;
182 }
183
184 static int ingress_drop(struct Qdisc *sch)
185 {
186 #ifdef DEBUG_INGRESS
187 struct ingress_qdisc_data *p = PRIV(sch);
188 #endif
189 DPRINTK("ingress_drop(sch %p,[qdisc %p])\n", sch, p);
190 return 0;
191 }
192
193 static unsigned int
194 ing_hook(unsigned int hook, struct sk_buff **pskb,
195 const struct net_device *indev,
196 const struct net_device *outdev,
197 int (*okfn)(struct sk_buff *))
198 {
199
200 struct Qdisc *q;
201 struct sk_buff *skb = *pskb;
202 struct net_device *dev = skb->dev;
203 int fwres=NF_ACCEPT;
204
205 DPRINTK("ing_hook: skb %s dev=%s len=%u\n",
206 skb->sk ? "(owned)" : "(unowned)",
207 skb->dev ? (*pskb)->dev->name : "(no dev)",
208 skb->len);
209
210 /*
211 revisit later: Use a private since lock dev->queue_lock is also
212 used on the egress (might slow things for an iota)
213 */
214
215 if (dev->qdisc_ingress) {
216 spin_lock(&dev->queue_lock);
217 if ((q = dev->qdisc_ingress) != NULL)
218 fwres = q->enqueue(skb, q);
219 spin_unlock(&dev->queue_lock);
220 }
221
222 return fwres;
223 }
224
225 /* after ipt_filter */
226 static struct nf_hook_ops ing_ops =
227 {
228 { NULL, NULL},
229 ing_hook,
230 PF_INET,
231 NF_IP_PRE_ROUTING,
232 NF_IP_PRI_FILTER + 1
233 };
234
235 int ingress_init(struct Qdisc *sch,struct rtattr *opt)
236 {
237 struct ingress_qdisc_data *p = PRIV(sch);
238
239 DPRINTK("ingress_init(sch %p,[qdisc %p],opt %p)\n",sch,p,opt);
240 memset(p, 0, sizeof(*p));
241 p->filter_list = NULL;
242 p->q = &noop_qdisc;
243 #ifndef MODULE
244 if (nf_register_hook(&ing_ops) < 0) {
245 printk("Unable to register ingress \n");
246 goto error;
247 }
248 #endif
249 DPRINTK("ingress_init: qdisc %p\n", sch);
250 MOD_INC_USE_COUNT;
251 return 0;
252 #ifndef MODULE
253 error:
254 #endif
255 return -EINVAL;
256 }
257
258
259 static void ingress_reset(struct Qdisc *sch)
260 {
261 struct ingress_qdisc_data *p = PRIV(sch);
262
263 DPRINTK("ingress_reset(sch %p,[qdisc %p])\n", sch, p);
264
265 /*
266 #if 0
267 */
268 /* for future use */
269 qdisc_reset(p->q);
270 /*
271 #endif
272 */
273 }
274
275 /* ------------------------------------------------------------- */
276
277
278 /* ------------------------------------------------------------- */
279
280 static void ingress_destroy(struct Qdisc *sch)
281 {
282 struct ingress_qdisc_data *p = PRIV(sch);
283 struct tcf_proto *tp;
284
285 DPRINTK("ingress_destroy(sch %p,[qdisc %p])\n", sch, p);
286 while (p->filter_list) {
287 tp = p->filter_list;
288 p->filter_list = tp->next;
289 tp->ops->destroy(tp);
290 }
291 memset(p, 0, sizeof(*p));
292 p->filter_list = NULL;
293
294 #if 0
295 /* for future use */
296 qdisc_destroy(p->q);
297 #endif
298
299 #ifndef MODULE
300 nf_unregister_hook(&ing_ops);
301 #endif
302
303 MOD_DEC_USE_COUNT;
304 }
305
306
307 #ifdef CONFIG_RTNETLINK
308
309
310 static int ingress_dump(struct Qdisc *sch, struct sk_buff *skb)
311 {
312 unsigned char *b = skb->tail;
313 struct rtattr *rta;
314
315 rta = (struct rtattr *) b;
316 RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
317 rta->rta_len = skb->tail - b;
318 return skb->len;
319
320 rtattr_failure:
321 skb_trim(skb, b - skb->data);
322 return -1;
323 }
324
325 #endif
326
327
328 static struct Qdisc_class_ops ingress_class_ops =
329 {
330 ingress_graft, /* graft */
331 ingress_leaf, /* leaf */
332 ingress_get, /* get */
333 ingress_put, /* put */
334 ingress_change, /* change */
335 NULL, /* delete */
336 ingress_walk, /* walk */
337
338 ingress_find_tcf, /* tcf_chain */
339 ingress_bind_filter, /* bind_tcf */
340 ingress_put, /* unbind_tcf */
341
342 #ifdef CONFIG_RTNETLINK
343 NULL, /* dump */
344 #endif
345 };
346
347 struct Qdisc_ops ingress_qdisc_ops =
348 {
349 NULL, /* next */
350 &ingress_class_ops, /* cl_ops */
351 "ingress",
352 sizeof(struct ingress_qdisc_data),
353
354 ingress_enqueue, /* enqueue */
355 ingress_dequeue, /* dequeue */
356 ingress_requeue, /* requeue */
357 ingress_drop, /* drop */
358
359 ingress_init, /* init */
360 ingress_reset, /* reset */
361 ingress_destroy, /* destroy */
362 NULL, /* change */
363
364 #ifdef CONFIG_RTNETLINK
365 ingress_dump, /* dump */
366 #endif
367 };
368
369 #ifdef MODULE
370 int init_module(void)
371 {
372 int ret = 0;
373
374 if ((ret = register_qdisc(&ingress_qdisc_ops)) < 0) {
375 printk("Unable to register Ingress qdisc\n");
376 return ret;
377 }
378
379 if (nf_register_hook(&ing_ops) < 0) {
380 printk("Unable to register ingress on hook \n");
381 unregister_qdisc(&ingress_qdisc_ops);
382 return 0;
383 }
384
385 return ret;
386 }
387
388
389 void cleanup_module(void)
390 {
391 nf_unregister_hook(&ing_ops);
392 unregister_qdisc(&ingress_qdisc_ops);
393 }
394 #endif
395