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                         skb->tc_index = TC_H_MIN(res.classid);
 162                 default:
 163                         result = TC_ACT_OK;
 164                         break;
 165         }
 166 #else
 167         D2PRINTK("Overriding result to ACCEPT\n");
 168         result = NF_ACCEPT;
 169         sch->bstats.packets++;
 170         sch->bstats.bytes += skb->len;
 171 #endif
 172
 173         return result;
 174 }
 175
 176
 177 static struct sk_buff *ingress_dequeue(struct Qdisc *sch)
 178 {
 179 /*
 180         struct ingress_qdisc_data *p = PRIV(sch);
 181         D2PRINTK("ingress_dequeue(sch %p,[qdisc %p])\n",sch,PRIV(p));
 182 */
 183         return NULL;
 184 }
 185
 186
 187 static int ingress_requeue(struct sk_buff *skb,struct Qdisc *sch)
 188 {
 189 /*
 190         struct ingress_qdisc_data *p = PRIV(sch);
 191         D2PRINTK("ingress_requeue(skb %p,sch %p,[qdisc %p])\n",skb,sch,PRIV(p));
 192 */
 193         return 0;
 194 }
 195
 196 static unsigned int ingress_drop(struct Qdisc *sch)
 197 {
 198 #ifdef DEBUG_INGRESS
 199         struct ingress_qdisc_data *p = PRIV(sch);
 200 #endif
 201         DPRINTK("ingress_drop(sch %p,[qdisc %p])\n", sch, p);
 202         return 0;
 203 }
 204
 205 #ifndef CONFIG_NET_CLS_ACT
 206 #ifdef CONFIG_NETFILTER
 207 static unsigned int
 208 ing_hook(unsigned int hook, struct sk_buff *skb,
 209                              const struct net_device *indev,
 210                              const struct net_device *outdev,
 211                              int (*okfn)(struct sk_buff *))
 212 {
 213
 214         struct Qdisc *q;
 215         struct net_device *dev = skb->dev;
 216         int fwres=NF_ACCEPT;
 217
 218         DPRINTK("ing_hook: skb %s dev=%s len=%u\n",
 219                 skb->sk ? "(owned)" : "(unowned)",
 220                 skb->dev ? skb->dev->name : "(no dev)",
 221                 skb->len);
 222
 223         if (dev->qdisc_ingress) {
 224                 spin_lock(&dev->ingress_lock);
 225                 if ((q = dev->qdisc_ingress) != NULL)
 226                         fwres = q->enqueue(skb, q);
 227                 spin_unlock(&dev->ingress_lock);
 228         }
 229
 230         return fwres;
 231 }
 232
 233 /* after ipt_filter */
 234 static struct nf_hook_ops ing_ops = {
 235         .hook           = ing_hook,
 236         .owner          = THIS_MODULE,
 237         .pf             = PF_INET,
 238         .hooknum        = NF_IP_PRE_ROUTING,
 239         .priority       = NF_IP_PRI_FILTER + 1,
 240 };
 241
 242 static struct nf_hook_ops ing6_ops = {
 243         .hook           = ing_hook,
 244         .owner          = THIS_MODULE,
 245         .pf             = PF_INET6,
 246         .hooknum        = NF_IP6_PRE_ROUTING,
 247         .priority       = NF_IP6_PRI_FILTER + 1,
 248 };
 249
 250 #endif
 251 #endif
 252
 253 static int ingress_init(struct Qdisc *sch,struct rtattr *opt)
 254 {
 255         struct ingress_qdisc_data *p = PRIV(sch);
 256
 257 /* Make sure either netfilter or preferably CLS_ACT is
 258 * compiled in */
 259 #ifndef CONFIG_NET_CLS_ACT
 260 #ifndef CONFIG_NETFILTER
 261         printk("You MUST compile classifier actions into the kernel\n");
 262         return -EINVAL;
 263 #else
 264         printk("Ingress scheduler: Classifier actions prefered over netfilter\n");
 265 #endif
 266 #endif
 267
 268 #ifndef CONFIG_NET_CLS_ACT
 269 #ifdef CONFIG_NETFILTER
 270         if (!nf_registered) {
 271                 if (nf_register_hook(&ing_ops) < 0) {
 272                         printk("ingress qdisc registration error \n");
 273                         return -EINVAL;
 274                 }
 275                 nf_registered++;
 276
 277                 if (nf_register_hook(&ing6_ops) < 0) {
 278                         printk("IPv6 ingress qdisc registration error, " \
 279                             "disabling IPv6 support.\n");
 280                 } else
 281                         nf_registered++;
 282         }
 283 #endif
 284 #endif
 285
 286         DPRINTK("ingress_init(sch %p,[qdisc %p],opt %p)\n",sch,p,opt);
 287         p->q = &noop_qdisc;
 288         return 0;
 289 }
 290
 291
 292 static void ingress_reset(struct Qdisc *sch)
 293 {
 294         struct ingress_qdisc_data *p = PRIV(sch);
 295
 296         DPRINTK("ingress_reset(sch %p,[qdisc %p])\n", sch, p);
 297
 298 /*
 299 #if 0
 300 */
 301 /* for future use */
 302         qdisc_reset(p->q);
 303 /*
 304 #endif
 305 */
 306 }
 307
 308 /* ------------------------------------------------------------- */
 309
 310
 311 /* ------------------------------------------------------------- */
 312
 313 static void ingress_destroy(struct Qdisc *sch)
 314 {
 315         struct ingress_qdisc_data *p = PRIV(sch);
 316
 317         DPRINTK("ingress_destroy(sch %p,[qdisc %p])\n", sch, p);
 318         tcf_destroy_chain(p->filter_list);
 319 #if 0
 320 /* for future use */
 321         qdisc_destroy(p->q);
 322 #endif
 323 }
 324
 325
 326 static int ingress_dump(struct Qdisc *sch, struct sk_buff *skb)
 327 {
 328         unsigned char *b = skb_tail_pointer(skb);
 329         struct rtattr *rta;
 330
 331         rta = (struct rtattr *) b;
 332         RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 333         rta->rta_len = skb_tail_pointer(skb) - b;
 334         return skb->len;
 335
 336 rtattr_failure:
 337         nlmsg_trim(skb, b);
 338         return -1;
 339 }
 340
 341 static struct Qdisc_class_ops ingress_class_ops = {
 342         .graft          =       ingress_graft,
 343         .leaf           =       ingress_leaf,
 344         .get            =       ingress_get,
 345         .put            =       ingress_put,
 346         .change         =       ingress_change,
 347         .delete         =       NULL,
 348         .walk           =       ingress_walk,
 349         .tcf_chain      =       ingress_find_tcf,
 350         .bind_tcf       =       ingress_bind_filter,
 351         .unbind_tcf     =       ingress_put,
 352         .dump           =       NULL,
 353 };
 354
 355 static struct Qdisc_ops ingress_qdisc_ops = {
 356         .next           =       NULL,
 357         .cl_ops         =       &ingress_class_ops,
 358         .id             =       "ingress",
 359         .priv_size      =       sizeof(struct ingress_qdisc_data),
 360         .enqueue        =       ingress_enqueue,
 361         .dequeue        =       ingress_dequeue,
 362         .requeue        =       ingress_requeue,
 363         .drop           =       ingress_drop,
 364         .init           =       ingress_init,
 365         .reset          =       ingress_reset,
 366         .destroy        =       ingress_destroy,
 367         .change         =       NULL,
 368         .dump           =       ingress_dump,
 369         .owner          =       THIS_MODULE,
 370 };
 371
 372 static int __init ingress_module_init(void)
 373 {
 374         int ret = 0;
 375
 376         if ((ret = register_qdisc(&ingress_qdisc_ops)) < 0) {
 377                 printk("Unable to register Ingress qdisc\n");
 378                 return ret;
 379         }
 380
 381         return ret;
 382 }
 383 static void __exit ingress_module_exit(void)
 384 {
 385         unregister_qdisc(&ingress_qdisc_ops);
 386 #ifndef CONFIG_NET_CLS_ACT
 387 #ifdef CONFIG_NETFILTER
 388         if (nf_registered) {
 389                 nf_unregister_hook(&ing_ops);
 390                 if (nf_registered > 1)
 391                         nf_unregister_hook(&ing6_ops);
 392         }
 393 #endif
 394 #endif
 395 }
 396 module_init(ingress_module_init)
 397 module_exit(ingress_module_exit)
 398 MODULE_LICENSE("GPL");