[SK_BUFF]: Convert skb->tail to sk_buff_data_t
[linux-2.6.git] / 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/skbuff.h>
13 #include <linux/netdevice.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 <linux/smp.h>
19 #include <net/pkt_sched.h>
20 #include <asm/byteorder.h>
21 #include <asm/uaccess.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) qdisc_priv(sch)
44
45
46 /* Thanks to Doron Oz for this hack
47 */
48 #ifndef CONFIG_NET_CLS_ACT
49 #ifdef CONFIG_NETFILTER
50 static int nf_registered;
51 #endif
52 #endif
53
54 struct ingress_qdisc_data {
55         struct Qdisc            *q;
56         struct tcf_proto        *filter_list;
57 };
58
59
60 /* ------------------------- Class/flow operations ------------------------- */
61
62
63 static int ingress_graft(struct Qdisc *sch,unsigned long arg,
64     struct Qdisc *new,struct Qdisc **old)
65 {
66 #ifdef DEBUG_INGRESS
67         struct ingress_qdisc_data *p = PRIV(sch);
68 #endif
69
70         DPRINTK("ingress_graft(sch %p,[qdisc %p],new %p,old %p)\n",
71                 sch, p, new, old);
72         DPRINTK("\n ingress_graft: You cannot add qdiscs to classes");
73         return 1;
74 }
75
76
77 static struct Qdisc *ingress_leaf(struct Qdisc *sch, unsigned long arg)
78 {
79         return NULL;
80 }
81
82
83 static unsigned long ingress_get(struct Qdisc *sch,u32 classid)
84 {
85 #ifdef DEBUG_INGRESS
86         struct ingress_qdisc_data *p = PRIV(sch);
87 #endif
88         DPRINTK("ingress_get(sch %p,[qdisc %p],classid %x)\n", sch, p, classid);
89         return TC_H_MIN(classid) + 1;
90 }
91
92
93 static unsigned long ingress_bind_filter(struct Qdisc *sch,
94     unsigned long parent, u32 classid)
95 {
96         return ingress_get(sch, classid);
97 }
98
99
100 static void ingress_put(struct Qdisc *sch, unsigned long cl)
101 {
102 }
103
104
105 static int ingress_change(struct Qdisc *sch, u32 classid, u32 parent,
106     struct rtattr **tca, unsigned long *arg)
107 {
108 #ifdef DEBUG_INGRESS
109         struct ingress_qdisc_data *p = PRIV(sch);
110 #endif
111         DPRINTK("ingress_change(sch %p,[qdisc %p],classid %x,parent %x),"
112                 "arg 0x%lx\n", sch, p, classid, parent, *arg);
113         DPRINTK("No effect. sch_ingress doesn't maintain classes at the moment");
114         return 0;
115 }
116
117
118
119 static void ingress_walk(struct Qdisc *sch,struct qdisc_walker *walker)
120 {
121 #ifdef DEBUG_INGRESS
122         struct ingress_qdisc_data *p = PRIV(sch);
123 #endif
124         DPRINTK("ingress_walk(sch %p,[qdisc %p],walker %p)\n", sch, p, walker);
125         DPRINTK("No effect. sch_ingress doesn't maintain classes at the moment");
126 }
127
128
129 static struct tcf_proto **ingress_find_tcf(struct Qdisc *sch,unsigned long cl)
130 {
131         struct ingress_qdisc_data *p = PRIV(sch);
132
133         return &p->filter_list;
134 }
135
136
137 /* --------------------------- Qdisc operations ---------------------------- */
138
139
140 static int ingress_enqueue(struct sk_buff *skb,struct Qdisc *sch)
141 {
142         struct ingress_qdisc_data *p = PRIV(sch);
143         struct tcf_result res;
144         int result;
145
146         D2PRINTK("ingress_enqueue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
147         result = tc_classify(skb, p->filter_list, &res);
148         D2PRINTK("result %d class 0x%04x\n", result, res.classid);
149         /*
150          * Unlike normal "enqueue" functions, ingress_enqueue returns a
151          * firewall FW_* code.
152          */
153 #ifdef CONFIG_NET_CLS_ACT
154         sch->bstats.packets++;
155         sch->bstats.bytes += skb->len;
156         switch (result) {
157                 case TC_ACT_SHOT:
158                         result = TC_ACT_SHOT;
159                         sch->qstats.drops++;
160                         break;
161                 case TC_ACT_STOLEN:
162                 case TC_ACT_QUEUED:
163                         result = TC_ACT_STOLEN;
164                         break;
165                 case TC_ACT_RECLASSIFY:
166                 case TC_ACT_OK:
167                 case TC_ACT_UNSPEC:
168                 default:
169                         skb->tc_index = TC_H_MIN(res.classid);
170                         result = TC_ACT_OK;
171                         break;
172         };
173 /* backward compat */
174 #else
175 #ifdef  CONFIG_NET_CLS_POLICE
176         switch (result) {
177                 case TC_POLICE_SHOT:
178                 result = NF_DROP;
179                 sch->qstats.drops++;
180                 break;
181                 case TC_POLICE_RECLASSIFY: /* DSCP remarking here ? */
182                 case TC_POLICE_OK:
183                 case TC_POLICE_UNSPEC:
184                 default:
185                 sch->bstats.packets++;
186                 sch->bstats.bytes += skb->len;
187                 result = NF_ACCEPT;
188                 break;
189         };
190
191 #else
192         D2PRINTK("Overriding result to ACCEPT\n");
193         result = NF_ACCEPT;
194         sch->bstats.packets++;
195         sch->bstats.bytes += skb->len;
196 #endif
197 #endif
198
199         return result;
200 }
201
202
203 static struct sk_buff *ingress_dequeue(struct Qdisc *sch)
204 {
205 /*
206         struct ingress_qdisc_data *p = PRIV(sch);
207         D2PRINTK("ingress_dequeue(sch %p,[qdisc %p])\n",sch,PRIV(p));
208 */
209         return NULL;
210 }
211
212
213 static int ingress_requeue(struct sk_buff *skb,struct Qdisc *sch)
214 {
215 /*
216         struct ingress_qdisc_data *p = PRIV(sch);
217         D2PRINTK("ingress_requeue(skb %p,sch %p,[qdisc %p])\n",skb,sch,PRIV(p));
218 */
219         return 0;
220 }
221
222 static unsigned int ingress_drop(struct Qdisc *sch)
223 {
224 #ifdef DEBUG_INGRESS
225         struct ingress_qdisc_data *p = PRIV(sch);
226 #endif
227         DPRINTK("ingress_drop(sch %p,[qdisc %p])\n", sch, p);
228         return 0;
229 }
230
231 #ifndef CONFIG_NET_CLS_ACT
232 #ifdef CONFIG_NETFILTER
233 static unsigned int
234 ing_hook(unsigned int hook, struct sk_buff **pskb,
235                              const struct net_device *indev,
236                              const struct net_device *outdev,
237                              int (*okfn)(struct sk_buff *))
238 {
239
240         struct Qdisc *q;
241         struct sk_buff *skb = *pskb;
242         struct net_device *dev = skb->dev;
243         int fwres=NF_ACCEPT;
244
245         DPRINTK("ing_hook: skb %s dev=%s len=%u\n",
246                 skb->sk ? "(owned)" : "(unowned)",
247                 skb->dev ? (*pskb)->dev->name : "(no dev)",
248                 skb->len);
249
250 /*
251 revisit later: Use a private since lock dev->queue_lock is also
252 used on the egress (might slow things for an iota)
253 */
254
255         if (dev->qdisc_ingress) {
256                 spin_lock(&dev->queue_lock);
257                 if ((q = dev->qdisc_ingress) != NULL)
258                         fwres = q->enqueue(skb, q);
259                 spin_unlock(&dev->queue_lock);
260         }
261
262         return fwres;
263 }
264
265 /* after ipt_filter */
266 static struct nf_hook_ops ing_ops = {
267         .hook           = ing_hook,
268         .owner          = THIS_MODULE,
269         .pf             = PF_INET,
270         .hooknum        = NF_IP_PRE_ROUTING,
271         .priority       = NF_IP_PRI_FILTER + 1,
272 };
273
274 static struct nf_hook_ops ing6_ops = {
275         .hook           = ing_hook,
276         .owner          = THIS_MODULE,
277         .pf             = PF_INET6,
278         .hooknum        = NF_IP6_PRE_ROUTING,
279         .priority       = NF_IP6_PRI_FILTER + 1,
280 };
281
282 #endif
283 #endif
284
285 static int ingress_init(struct Qdisc *sch,struct rtattr *opt)
286 {
287         struct ingress_qdisc_data *p = PRIV(sch);
288
289 /* Make sure either netfilter or preferably CLS_ACT is
290 * compiled in */
291 #ifndef CONFIG_NET_CLS_ACT
292 #ifndef CONFIG_NETFILTER
293         printk("You MUST compile classifier actions into the kernel\n");
294         return -EINVAL;
295 #else
296         printk("Ingress scheduler: Classifier actions prefered over netfilter\n");
297 #endif
298 #endif
299
300 #ifndef CONFIG_NET_CLS_ACT
301 #ifdef CONFIG_NETFILTER
302         if (!nf_registered) {
303                 if (nf_register_hook(&ing_ops) < 0) {
304                         printk("ingress qdisc registration error \n");
305                         return -EINVAL;
306                 }
307                 nf_registered++;
308
309                 if (nf_register_hook(&ing6_ops) < 0) {
310                         printk("IPv6 ingress qdisc registration error, " \
311                             "disabling IPv6 support.\n");
312                 } else
313                         nf_registered++;
314         }
315 #endif
316 #endif
317
318         DPRINTK("ingress_init(sch %p,[qdisc %p],opt %p)\n",sch,p,opt);
319         p->q = &noop_qdisc;
320         return 0;
321 }
322
323
324 static void ingress_reset(struct Qdisc *sch)
325 {
326         struct ingress_qdisc_data *p = PRIV(sch);
327
328         DPRINTK("ingress_reset(sch %p,[qdisc %p])\n", sch, p);
329
330 /*
331 #if 0
332 */
333 /* for future use */
334         qdisc_reset(p->q);
335 /*
336 #endif
337 */
338 }
339
340 /* ------------------------------------------------------------- */
341
342
343 /* ------------------------------------------------------------- */
344
345 static void ingress_destroy(struct Qdisc *sch)
346 {
347         struct ingress_qdisc_data *p = PRIV(sch);
348         struct tcf_proto *tp;
349
350         DPRINTK("ingress_destroy(sch %p,[qdisc %p])\n", sch, p);
351         while (p->filter_list) {
352                 tp = p->filter_list;
353                 p->filter_list = tp->next;
354                 tcf_destroy(tp);
355         }
356 #if 0
357 /* for future use */
358         qdisc_destroy(p->q);
359 #endif
360 }
361
362
363 static int ingress_dump(struct Qdisc *sch, struct sk_buff *skb)
364 {
365         unsigned char *b = skb_tail_pointer(skb);
366         struct rtattr *rta;
367
368         rta = (struct rtattr *) b;
369         RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
370         rta->rta_len = skb_tail_pointer(skb) - b;
371         return skb->len;
372
373 rtattr_failure:
374         skb_trim(skb, b - skb->data);
375         return -1;
376 }
377
378 static struct Qdisc_class_ops ingress_class_ops = {
379         .graft          =       ingress_graft,
380         .leaf           =       ingress_leaf,
381         .get            =       ingress_get,
382         .put            =       ingress_put,
383         .change         =       ingress_change,
384         .delete         =       NULL,
385         .walk           =       ingress_walk,
386         .tcf_chain      =       ingress_find_tcf,
387         .bind_tcf       =       ingress_bind_filter,
388         .unbind_tcf     =       ingress_put,
389         .dump           =       NULL,
390 };
391
392 static struct Qdisc_ops ingress_qdisc_ops = {
393         .next           =       NULL,
394         .cl_ops         =       &ingress_class_ops,
395         .id             =       "ingress",
396         .priv_size      =       sizeof(struct ingress_qdisc_data),
397         .enqueue        =       ingress_enqueue,
398         .dequeue        =       ingress_dequeue,
399         .requeue        =       ingress_requeue,
400         .drop           =       ingress_drop,
401         .init           =       ingress_init,
402         .reset          =       ingress_reset,
403         .destroy        =       ingress_destroy,
404         .change         =       NULL,
405         .dump           =       ingress_dump,
406         .owner          =       THIS_MODULE,
407 };
408
409 static int __init ingress_module_init(void)
410 {
411         int ret = 0;
412
413         if ((ret = register_qdisc(&ingress_qdisc_ops)) < 0) {
414                 printk("Unable to register Ingress qdisc\n");
415                 return ret;
416         }
417
418         return ret;
419 }
420 static void __exit ingress_module_exit(void)
421 {
422         unregister_qdisc(&ingress_qdisc_ops);
423 #ifndef CONFIG_NET_CLS_ACT
424 #ifdef CONFIG_NETFILTER
425         if (nf_registered) {
426                 nf_unregister_hook(&ing_ops);
427                 if (nf_registered > 1)
428                         nf_unregister_hook(&ing6_ops);
429         }
430 #endif
431 #endif
432 }
433 module_init(ingress_module_init)
434 module_exit(ingress_module_exit)
435 MODULE_LICENSE("GPL");