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");