Pull bugzilla-7880 into release branch
[linux-2.6] / 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/module.h>
11 #include <linux/types.h>
12 #include <linux/list.h>
13 #include <linux/skbuff.h>
14 #include <linux/rtnetlink.h>
15 #include <linux/netfilter_ipv4.h>
16 #include <linux/netfilter_ipv6.h>
17 #include <linux/netfilter.h>
18 #include <net/netlink.h>
19 #include <net/pkt_sched.h>
20
21
22 #undef DEBUG_INGRESS
23
24 #ifdef DEBUG_INGRESS  /* control */
25 #define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
26 #else
27 #define DPRINTK(format,args...)
28 #endif
29
30 #if 0  /* data */
31 #define D2PRINTK(format,args...) printk(KERN_DEBUG format,##args)
32 #else
33 #define D2PRINTK(format,args...)
34 #endif
35
36
37 #define PRIV(sch) qdisc_priv(sch)
38
39
40 /* Thanks to Doron Oz for this hack
41 */
42 #ifndef CONFIG_NET_CLS_ACT
43 #ifdef CONFIG_NETFILTER
44 static int nf_registered;
45 #endif
46 #endif
47
48 struct ingress_qdisc_data {
49         struct Qdisc            *q;
50         struct tcf_proto        *filter_list;
51 };
52
53
54 /* ------------------------- Class/flow operations ------------------------- */
55
56
57 static int ingress_graft(struct Qdisc *sch,unsigned long arg,
58     struct Qdisc *new,struct Qdisc **old)
59 {
60 #ifdef DEBUG_INGRESS
61         struct ingress_qdisc_data *p = PRIV(sch);
62 #endif
63
64         DPRINTK("ingress_graft(sch %p,[qdisc %p],new %p,old %p)\n",
65                 sch, p, new, old);
66         DPRINTK("\n ingress_graft: You cannot add qdiscs to classes");
67         return 1;
68 }
69
70
71 static struct Qdisc *ingress_leaf(struct Qdisc *sch, unsigned long arg)
72 {
73         return NULL;
74 }
75
76
77 static unsigned long ingress_get(struct Qdisc *sch,u32 classid)
78 {
79 #ifdef DEBUG_INGRESS
80         struct ingress_qdisc_data *p = PRIV(sch);
81 #endif
82         DPRINTK("ingress_get(sch %p,[qdisc %p],classid %x)\n", sch, p, classid);
83         return TC_H_MIN(classid) + 1;
84 }
85
86
87 static unsigned long ingress_bind_filter(struct Qdisc *sch,
88     unsigned long parent, u32 classid)
89 {
90         return ingress_get(sch, classid);
91 }
92
93
94 static void ingress_put(struct Qdisc *sch, unsigned long cl)
95 {
96 }
97
98
99 static int ingress_change(struct Qdisc *sch, u32 classid, u32 parent,
100     struct rtattr **tca, unsigned long *arg)
101 {
102 #ifdef DEBUG_INGRESS
103         struct ingress_qdisc_data *p = PRIV(sch);
104 #endif
105         DPRINTK("ingress_change(sch %p,[qdisc %p],classid %x,parent %x),"
106                 "arg 0x%lx\n", sch, p, classid, parent, *arg);
107         DPRINTK("No effect. sch_ingress doesn't maintain classes at the moment");
108         return 0;
109 }
110
111
112
113 static void ingress_walk(struct Qdisc *sch,struct qdisc_walker *walker)
114 {
115 #ifdef DEBUG_INGRESS
116         struct ingress_qdisc_data *p = PRIV(sch);
117 #endif
118         DPRINTK("ingress_walk(sch %p,[qdisc %p],walker %p)\n", sch, p, walker);
119         DPRINTK("No effect. sch_ingress doesn't maintain classes at the moment");
120 }
121
122
123 static struct tcf_proto **ingress_find_tcf(struct Qdisc *sch,unsigned long cl)
124 {
125         struct ingress_qdisc_data *p = PRIV(sch);
126
127         return &p->filter_list;
128 }
129
130
131 /* --------------------------- Qdisc operations ---------------------------- */
132
133
134 static int ingress_enqueue(struct sk_buff *skb,struct Qdisc *sch)
135 {
136         struct ingress_qdisc_data *p = PRIV(sch);
137         struct tcf_result res;
138         int result;
139
140         D2PRINTK("ingress_enqueue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
141         result = tc_classify(skb, p->filter_list, &res);
142         D2PRINTK("result %d class 0x%04x\n", result, res.classid);
143         /*
144          * Unlike normal "enqueue" functions, ingress_enqueue returns a
145          * firewall FW_* code.
146          */
147 #ifdef CONFIG_NET_CLS_ACT
148         sch->bstats.packets++;
149         sch->bstats.bytes += skb->len;
150         switch (result) {
151                 case TC_ACT_SHOT:
152                         result = TC_ACT_SHOT;
153                         sch->qstats.drops++;
154                         break;
155                 case TC_ACT_STOLEN:
156                 case TC_ACT_QUEUED:
157                         result = TC_ACT_STOLEN;
158                         break;
159                 case TC_ACT_RECLASSIFY:
160                 case TC_ACT_OK:
161                 case TC_ACT_UNSPEC:
162                 default:
163                         skb->tc_index = TC_H_MIN(res.classid);
164                         result = TC_ACT_OK;
165                         break;
166         }
167 #else
168         D2PRINTK("Overriding result to ACCEPT\n");
169         result = NF_ACCEPT;
170         sch->bstats.packets++;
171         sch->bstats.bytes += skb->len;
172 #endif
173
174         return result;
175 }
176
177
178 static struct sk_buff *ingress_dequeue(struct Qdisc *sch)
179 {
180 /*
181         struct ingress_qdisc_data *p = PRIV(sch);
182         D2PRINTK("ingress_dequeue(sch %p,[qdisc %p])\n",sch,PRIV(p));
183 */
184         return NULL;
185 }
186
187
188 static int ingress_requeue(struct sk_buff *skb,struct Qdisc *sch)
189 {
190 /*
191         struct ingress_qdisc_data *p = PRIV(sch);
192         D2PRINTK("ingress_requeue(skb %p,sch %p,[qdisc %p])\n",skb,sch,PRIV(p));
193 */
194         return 0;
195 }
196
197 static unsigned int ingress_drop(struct Qdisc *sch)
198 {
199 #ifdef DEBUG_INGRESS
200         struct ingress_qdisc_data *p = PRIV(sch);
201 #endif
202         DPRINTK("ingress_drop(sch %p,[qdisc %p])\n", sch, p);
203         return 0;
204 }
205
206 #ifndef CONFIG_NET_CLS_ACT
207 #ifdef CONFIG_NETFILTER
208 static unsigned int
209 ing_hook(unsigned int hook, struct sk_buff **pskb,
210                              const struct net_device *indev,
211                              const struct net_device *outdev,
212                              int (*okfn)(struct sk_buff *))
213 {
214
215         struct Qdisc *q;
216         struct sk_buff *skb = *pskb;
217         struct net_device *dev = skb->dev;
218         int fwres=NF_ACCEPT;
219
220         DPRINTK("ing_hook: skb %s dev=%s len=%u\n",
221                 skb->sk ? "(owned)" : "(unowned)",
222                 skb->dev ? (*pskb)->dev->name : "(no dev)",
223                 skb->len);
224
225         if (dev->qdisc_ingress) {
226                 spin_lock(&dev->ingress_lock);
227                 if ((q = dev->qdisc_ingress) != NULL)
228                         fwres = q->enqueue(skb, q);
229                 spin_unlock(&dev->ingress_lock);
230         }
231
232         return fwres;
233 }
234
235 /* after ipt_filter */
236 static struct nf_hook_ops ing_ops = {
237         .hook           = ing_hook,
238         .owner          = THIS_MODULE,
239         .pf             = PF_INET,
240         .hooknum        = NF_IP_PRE_ROUTING,
241         .priority       = NF_IP_PRI_FILTER + 1,
242 };
243
244 static struct nf_hook_ops ing6_ops = {
245         .hook           = ing_hook,
246         .owner          = THIS_MODULE,
247         .pf             = PF_INET6,
248         .hooknum        = NF_IP6_PRE_ROUTING,
249         .priority       = NF_IP6_PRI_FILTER + 1,
250 };
251
252 #endif
253 #endif
254
255 static int ingress_init(struct Qdisc *sch,struct rtattr *opt)
256 {
257         struct ingress_qdisc_data *p = PRIV(sch);
258
259 /* Make sure either netfilter or preferably CLS_ACT is
260 * compiled in */
261 #ifndef CONFIG_NET_CLS_ACT
262 #ifndef CONFIG_NETFILTER
263         printk("You MUST compile classifier actions into the kernel\n");
264         return -EINVAL;
265 #else
266         printk("Ingress scheduler: Classifier actions prefered over netfilter\n");
267 #endif
268 #endif
269
270 #ifndef CONFIG_NET_CLS_ACT
271 #ifdef CONFIG_NETFILTER
272         if (!nf_registered) {
273                 if (nf_register_hook(&ing_ops) < 0) {
274                         printk("ingress qdisc registration error \n");
275                         return -EINVAL;
276                 }
277                 nf_registered++;
278
279                 if (nf_register_hook(&ing6_ops) < 0) {
280                         printk("IPv6 ingress qdisc registration error, " \
281                             "disabling IPv6 support.\n");
282                 } else
283                         nf_registered++;
284         }
285 #endif
286 #endif
287
288         DPRINTK("ingress_init(sch %p,[qdisc %p],opt %p)\n",sch,p,opt);
289         p->q = &noop_qdisc;
290         return 0;
291 }
292
293
294 static void ingress_reset(struct Qdisc *sch)
295 {
296         struct ingress_qdisc_data *p = PRIV(sch);
297
298         DPRINTK("ingress_reset(sch %p,[qdisc %p])\n", sch, p);
299
300 /*
301 #if 0
302 */
303 /* for future use */
304         qdisc_reset(p->q);
305 /*
306 #endif
307 */
308 }
309
310 /* ------------------------------------------------------------- */
311
312
313 /* ------------------------------------------------------------- */
314
315 static void ingress_destroy(struct Qdisc *sch)
316 {
317         struct ingress_qdisc_data *p = PRIV(sch);
318
319         DPRINTK("ingress_destroy(sch %p,[qdisc %p])\n", sch, p);
320         tcf_destroy_chain(p->filter_list);
321 #if 0
322 /* for future use */
323         qdisc_destroy(p->q);
324 #endif
325 }
326
327
328 static int ingress_dump(struct Qdisc *sch, struct sk_buff *skb)
329 {
330         unsigned char *b = skb_tail_pointer(skb);
331         struct rtattr *rta;
332
333         rta = (struct rtattr *) b;
334         RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
335         rta->rta_len = skb_tail_pointer(skb) - b;
336         return skb->len;
337
338 rtattr_failure:
339         nlmsg_trim(skb, b);
340         return -1;
341 }
342
343 static struct Qdisc_class_ops ingress_class_ops = {
344         .graft          =       ingress_graft,
345         .leaf           =       ingress_leaf,
346         .get            =       ingress_get,
347         .put            =       ingress_put,
348         .change         =       ingress_change,
349         .delete         =       NULL,
350         .walk           =       ingress_walk,
351         .tcf_chain      =       ingress_find_tcf,
352         .bind_tcf       =       ingress_bind_filter,
353         .unbind_tcf     =       ingress_put,
354         .dump           =       NULL,
355 };
356
357 static struct Qdisc_ops ingress_qdisc_ops = {
358         .next           =       NULL,
359         .cl_ops         =       &ingress_class_ops,
360         .id             =       "ingress",
361         .priv_size      =       sizeof(struct ingress_qdisc_data),
362         .enqueue        =       ingress_enqueue,
363         .dequeue        =       ingress_dequeue,
364         .requeue        =       ingress_requeue,
365         .drop           =       ingress_drop,
366         .init           =       ingress_init,
367         .reset          =       ingress_reset,
368         .destroy        =       ingress_destroy,
369         .change         =       NULL,
370         .dump           =       ingress_dump,
371         .owner          =       THIS_MODULE,
372 };
373
374 static int __init ingress_module_init(void)
375 {
376         int ret = 0;
377
378         if ((ret = register_qdisc(&ingress_qdisc_ops)) < 0) {
379                 printk("Unable to register Ingress qdisc\n");
380                 return ret;
381         }
382
383         return ret;
384 }
385 static void __exit ingress_module_exit(void)
386 {
387         unregister_qdisc(&ingress_qdisc_ops);
388 #ifndef CONFIG_NET_CLS_ACT
389 #ifdef CONFIG_NETFILTER
390         if (nf_registered) {
391                 nf_unregister_hook(&ing_ops);
392                 if (nf_registered > 1)
393                         nf_unregister_hook(&ing6_ops);
394         }
395 #endif
396 #endif
397 }
398 module_init(ingress_module_init)
399 module_exit(ingress_module_exit)
400 MODULE_LICENSE("GPL");