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/netlink.h>
  20 #include <net/pkt_sched.h>
  21 #include <asm/byteorder.h>
  22 #include <asm/uaccess.h>
  23 #include <linux/kmod.h>
  24 #include <linux/stat.h>
  25 #include <linux/interrupt.h>
  26 #include <linux/list.h>
  27
  28
  29 #undef DEBUG_INGRESS
  30
  31 #ifdef DEBUG_INGRESS  /* control */
  32 #define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
  33 #else
  34 #define DPRINTK(format,args...)
  35 #endif
  36
  37 #if 0  /* data */
  38 #define D2PRINTK(format,args...) printk(KERN_DEBUG format,##args)
  39 #else
  40 #define D2PRINTK(format,args...)
  41 #endif
  42
  43
  44 #define PRIV(sch) qdisc_priv(sch)
  45
  46
  47 /* Thanks to Doron Oz for this hack
  48 */
  49 #ifndef CONFIG_NET_CLS_ACT
  50 #ifdef CONFIG_NETFILTER
  51 static int nf_registered;
  52 #endif
  53 #endif
  54
  55 struct ingress_qdisc_data {
  56         struct Qdisc            *q;
  57         struct tcf_proto        *filter_list;
  58 };
  59
  60
  61 /* ------------------------- Class/flow operations ------------------------- */
  62
  63
  64 static int ingress_graft(struct Qdisc *sch,unsigned long arg,
  65     struct Qdisc *new,struct Qdisc **old)
  66 {
  67 #ifdef DEBUG_INGRESS
  68         struct ingress_qdisc_data *p = PRIV(sch);
  69 #endif
  70
  71         DPRINTK("ingress_graft(sch %p,[qdisc %p],new %p,old %p)\n",
  72                 sch, p, new, old);
  73         DPRINTK("\n ingress_graft: You cannot add qdiscs to classes");
  74         return 1;
  75 }
  76
  77
  78 static struct Qdisc *ingress_leaf(struct Qdisc *sch, unsigned long arg)
  79 {
  80         return NULL;
  81 }
  82
  83
  84 static unsigned long ingress_get(struct Qdisc *sch,u32 classid)
  85 {
  86 #ifdef DEBUG_INGRESS
  87         struct ingress_qdisc_data *p = PRIV(sch);
  88 #endif
  89         DPRINTK("ingress_get(sch %p,[qdisc %p],classid %x)\n", sch, p, classid);
  90         return TC_H_MIN(classid) + 1;
  91 }
  92
  93
  94 static unsigned long ingress_bind_filter(struct Qdisc *sch,
  95     unsigned long parent, u32 classid)
  96 {
  97         return ingress_get(sch, classid);
  98 }
  99
 100
 101 static void ingress_put(struct Qdisc *sch, unsigned long cl)
 102 {
 103 }
 104
 105
 106 static int ingress_change(struct Qdisc *sch, u32 classid, u32 parent,
 107     struct rtattr **tca, unsigned long *arg)
 108 {
 109 #ifdef DEBUG_INGRESS
 110         struct ingress_qdisc_data *p = PRIV(sch);
 111 #endif
 112         DPRINTK("ingress_change(sch %p,[qdisc %p],classid %x,parent %x),"
 113                 "arg 0x%lx\n", sch, p, classid, parent, *arg);
 114         DPRINTK("No effect. sch_ingress doesn't maintain classes at the moment");
 115         return 0;
 116 }
 117
 118
 119
 120 static void ingress_walk(struct Qdisc *sch,struct qdisc_walker *walker)
 121 {
 122 #ifdef DEBUG_INGRESS
 123         struct ingress_qdisc_data *p = PRIV(sch);
 124 #endif
 125         DPRINTK("ingress_walk(sch %p,[qdisc %p],walker %p)\n", sch, p, walker);
 126         DPRINTK("No effect. sch_ingress doesn't maintain classes at the moment");
 127 }
 128
 129
 130 static struct tcf_proto **ingress_find_tcf(struct Qdisc *sch,unsigned long cl)
 131 {
 132         struct ingress_qdisc_data *p = PRIV(sch);
 133
 134         return &p->filter_list;
 135 }
 136
 137
 138 /* --------------------------- Qdisc operations ---------------------------- */
 139
 140
 141 static int ingress_enqueue(struct sk_buff *skb,struct Qdisc *sch)
 142 {
 143         struct ingress_qdisc_data *p = PRIV(sch);
 144         struct tcf_result res;
 145         int result;
 146
 147         D2PRINTK("ingress_enqueue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
 148         result = tc_classify(skb, p->filter_list, &res);
 149         D2PRINTK("result %d class 0x%04x\n", result, res.classid);
 150         /*
 151          * Unlike normal "enqueue" functions, ingress_enqueue returns a
 152          * firewall FW_* code.
 153          */
 154 #ifdef CONFIG_NET_CLS_ACT
 155         sch->bstats.packets++;
 156         sch->bstats.bytes += skb->len;
 157         switch (result) {
 158                 case TC_ACT_SHOT:
 159                         result = TC_ACT_SHOT;
 160                         sch->qstats.drops++;
 161                         break;
 162                 case TC_ACT_STOLEN:
 163                 case TC_ACT_QUEUED:
 164                         result = TC_ACT_STOLEN;
 165                         break;
 166                 case TC_ACT_RECLASSIFY:
 167                 case TC_ACT_OK:
 168                 case TC_ACT_UNSPEC:
 169                 default:
 170                         skb->tc_index = TC_H_MIN(res.classid);
 171                         result = TC_ACT_OK;
 172                         break;
 173         }
 174 /* backward compat */
 175 #else
 176 #ifdef  CONFIG_NET_CLS_POLICE
 177         switch (result) {
 178                 case TC_POLICE_SHOT:
 179                 result = NF_DROP;
 180                 sch->qstats.drops++;
 181                 break;
 182                 case TC_POLICE_RECLASSIFY: /* DSCP remarking here ? */
 183                 case TC_POLICE_OK:
 184                 case TC_POLICE_UNSPEC:
 185                 default:
 186                 sch->bstats.packets++;
 187                 sch->bstats.bytes += skb->len;
 188                 result = NF_ACCEPT;
 189                 break;
 190         }
 191
 192 #else
 193         D2PRINTK("Overriding result to ACCEPT\n");
 194         result = NF_ACCEPT;
 195         sch->bstats.packets++;
 196         sch->bstats.bytes += skb->len;
 197 #endif
 198 #endif
 199
 200         return result;
 201 }
 202
 203
 204 static struct sk_buff *ingress_dequeue(struct Qdisc *sch)
 205 {
 206 /*
 207         struct ingress_qdisc_data *p = PRIV(sch);
 208         D2PRINTK("ingress_dequeue(sch %p,[qdisc %p])\n",sch,PRIV(p));
 209 */
 210         return NULL;
 211 }
 212
 213
 214 static int ingress_requeue(struct sk_buff *skb,struct Qdisc *sch)
 215 {
 216 /*
 217         struct ingress_qdisc_data *p = PRIV(sch);
 218         D2PRINTK("ingress_requeue(skb %p,sch %p,[qdisc %p])\n",skb,sch,PRIV(p));
 219 */
 220         return 0;
 221 }
 222
 223 static unsigned int ingress_drop(struct Qdisc *sch)
 224 {
 225 #ifdef DEBUG_INGRESS
 226         struct ingress_qdisc_data *p = PRIV(sch);
 227 #endif
 228         DPRINTK("ingress_drop(sch %p,[qdisc %p])\n", sch, p);
 229         return 0;
 230 }
 231
 232 #ifndef CONFIG_NET_CLS_ACT
 233 #ifdef CONFIG_NETFILTER
 234 static unsigned int
 235 ing_hook(unsigned int hook, struct sk_buff **pskb,
 236                              const struct net_device *indev,
 237                              const struct net_device *outdev,
 238                              int (*okfn)(struct sk_buff *))
 239 {
 240
 241         struct Qdisc *q;
 242         struct sk_buff *skb = *pskb;
 243         struct net_device *dev = skb->dev;
 244         int fwres=NF_ACCEPT;
 245
 246         DPRINTK("ing_hook: skb %s dev=%s len=%u\n",
 247                 skb->sk ? "(owned)" : "(unowned)",
 248                 skb->dev ? (*pskb)->dev->name : "(no dev)",
 249                 skb->len);
 250
 251         if (dev->qdisc_ingress) {
 252                 spin_lock(&dev->ingress_lock);
 253                 if ((q = dev->qdisc_ingress) != NULL)
 254                         fwres = q->enqueue(skb, q);
 255                 spin_unlock(&dev->ingress_lock);
 256         }
 257
 258         return fwres;
 259 }
 260
 261 /* after ipt_filter */
 262 static struct nf_hook_ops ing_ops = {
 263         .hook           = ing_hook,
 264         .owner          = THIS_MODULE,
 265         .pf             = PF_INET,
 266         .hooknum        = NF_IP_PRE_ROUTING,
 267         .priority       = NF_IP_PRI_FILTER + 1,
 268 };
 269
 270 static struct nf_hook_ops ing6_ops = {
 271         .hook           = ing_hook,
 272         .owner          = THIS_MODULE,
 273         .pf             = PF_INET6,
 274         .hooknum        = NF_IP6_PRE_ROUTING,
 275         .priority       = NF_IP6_PRI_FILTER + 1,
 276 };
 277
 278 #endif
 279 #endif
 280
 281 static int ingress_init(struct Qdisc *sch,struct rtattr *opt)
 282 {
 283         struct ingress_qdisc_data *p = PRIV(sch);
 284
 285 /* Make sure either netfilter or preferably CLS_ACT is
 286 * compiled in */
 287 #ifndef CONFIG_NET_CLS_ACT
 288 #ifndef CONFIG_NETFILTER
 289         printk("You MUST compile classifier actions into the kernel\n");
 290         return -EINVAL;
 291 #else
 292         printk("Ingress scheduler: Classifier actions prefered over netfilter\n");
 293 #endif
 294 #endif
 295
 296 #ifndef CONFIG_NET_CLS_ACT
 297 #ifdef CONFIG_NETFILTER
 298         if (!nf_registered) {
 299                 if (nf_register_hook(&ing_ops) < 0) {
 300                         printk("ingress qdisc registration error \n");
 301                         return -EINVAL;
 302                 }
 303                 nf_registered++;
 304
 305                 if (nf_register_hook(&ing6_ops) < 0) {
 306                         printk("IPv6 ingress qdisc registration error, " \
 307                             "disabling IPv6 support.\n");
 308                 } else
 309                         nf_registered++;
 310         }
 311 #endif
 312 #endif
 313
 314         DPRINTK("ingress_init(sch %p,[qdisc %p],opt %p)\n",sch,p,opt);
 315         p->q = &noop_qdisc;
 316         return 0;
 317 }
 318
 319
 320 static void ingress_reset(struct Qdisc *sch)
 321 {
 322         struct ingress_qdisc_data *p = PRIV(sch);
 323
 324         DPRINTK("ingress_reset(sch %p,[qdisc %p])\n", sch, p);
 325
 326 /*
 327 #if 0
 328 */
 329 /* for future use */
 330         qdisc_reset(p->q);
 331 /*
 332 #endif
 333 */
 334 }
 335
 336 /* ------------------------------------------------------------- */
 337
 338
 339 /* ------------------------------------------------------------- */
 340
 341 static void ingress_destroy(struct Qdisc *sch)
 342 {
 343         struct ingress_qdisc_data *p = PRIV(sch);
 344
 345         DPRINTK("ingress_destroy(sch %p,[qdisc %p])\n", sch, p);
 346         tcf_destroy_chain(p->filter_list);
 347 #if 0
 348 /* for future use */
 349         qdisc_destroy(p->q);
 350 #endif
 351 }
 352
 353
 354 static int ingress_dump(struct Qdisc *sch, struct sk_buff *skb)
 355 {
 356         unsigned char *b = skb_tail_pointer(skb);
 357         struct rtattr *rta;
 358
 359         rta = (struct rtattr *) b;
 360         RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 361         rta->rta_len = skb_tail_pointer(skb) - b;
 362         return skb->len;
 363
 364 rtattr_failure:
 365         nlmsg_trim(skb, b);
 366         return -1;
 367 }
 368
 369 static struct Qdisc_class_ops ingress_class_ops = {
 370         .graft          =       ingress_graft,
 371         .leaf           =       ingress_leaf,
 372         .get            =       ingress_get,
 373         .put            =       ingress_put,
 374         .change         =       ingress_change,
 375         .delete         =       NULL,
 376         .walk           =       ingress_walk,
 377         .tcf_chain      =       ingress_find_tcf,
 378         .bind_tcf       =       ingress_bind_filter,
 379         .unbind_tcf     =       ingress_put,
 380         .dump           =       NULL,
 381 };
 382
 383 static struct Qdisc_ops ingress_qdisc_ops = {
 384         .next           =       NULL,
 385         .cl_ops         =       &ingress_class_ops,
 386         .id             =       "ingress",
 387         .priv_size      =       sizeof(struct ingress_qdisc_data),
 388         .enqueue        =       ingress_enqueue,
 389         .dequeue        =       ingress_dequeue,
 390         .requeue        =       ingress_requeue,
 391         .drop           =       ingress_drop,
 392         .init           =       ingress_init,
 393         .reset          =       ingress_reset,
 394         .destroy        =       ingress_destroy,
 395         .change         =       NULL,
 396         .dump           =       ingress_dump,
 397         .owner          =       THIS_MODULE,
 398 };
 399
 400 static int __init ingress_module_init(void)
 401 {
 402         int ret = 0;
 403
 404         if ((ret = register_qdisc(&ingress_qdisc_ops)) < 0) {
 405                 printk("Unable to register Ingress qdisc\n");
 406                 return ret;
 407         }
 408
 409         return ret;
 410 }
 411 static void __exit ingress_module_exit(void)
 412 {
 413         unregister_qdisc(&ingress_qdisc_ops);
 414 #ifndef CONFIG_NET_CLS_ACT
 415 #ifdef CONFIG_NETFILTER
 416         if (nf_registered) {
 417                 nf_unregister_hook(&ing_ops);
 418                 if (nf_registered > 1)
 419                         nf_unregister_hook(&ing6_ops);
 420         }
 421 #endif
 422 #endif
 423 }
 424 module_init(ingress_module_init)
 425 module_exit(ingress_module_exit)
 426 MODULE_LICENSE("GPL");