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/config.h>
  11 #include <linux/module.h>
  12 #include <linux/types.h>
  13 #include <linux/skbuff.h>
  14 #include <linux/netdevice.h>
  15 #include <linux/rtnetlink.h>
  16 #include <linux/netfilter_ipv4.h>
  17 #include <linux/netfilter_ipv6.h>
  18 #include <linux/netfilter.h>
  19 #include <linux/smp.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 /*
 252 revisit later: Use a private since lock dev->queue_lock is also
 253 used on the egress (might slow things for an iota)
 254 */
 255
 256         if (dev->qdisc_ingress) {
 257                 spin_lock(&dev->queue_lock);
 258                 if ((q = dev->qdisc_ingress) != NULL)
 259                         fwres = q->enqueue(skb, q);
 260                 spin_unlock(&dev->queue_lock);
 261         }
 262
 263         return fwres;
 264 }
 265
 266 /* after ipt_filter */
 267 static struct nf_hook_ops ing_ops = {
 268         .hook           = ing_hook,
 269         .owner          = THIS_MODULE,
 270         .pf             = PF_INET,
 271         .hooknum        = NF_IP_PRE_ROUTING,
 272         .priority       = NF_IP_PRI_FILTER + 1,
 273 };
 274
 275 static struct nf_hook_ops ing6_ops = {
 276         .hook           = ing_hook,
 277         .owner          = THIS_MODULE,
 278         .pf             = PF_INET6,
 279         .hooknum        = NF_IP6_PRE_ROUTING,
 280         .priority       = NF_IP6_PRI_FILTER + 1,
 281 };
 282
 283 #endif
 284 #endif
 285
 286 static int ingress_init(struct Qdisc *sch,struct rtattr *opt)
 287 {
 288         struct ingress_qdisc_data *p = PRIV(sch);
 289
 290 /* Make sure either netfilter or preferably CLS_ACT is
 291 * compiled in */
 292 #ifndef CONFIG_NET_CLS_ACT
 293 #ifndef CONFIG_NETFILTER
 294         printk("You MUST compile classifier actions into the kernel\n");
 295         return -EINVAL;
 296 #else
 297         printk("Ingress scheduler: Classifier actions prefered over netfilter\n");
 298 #endif
 299 #endif
 300
 301 #ifndef CONFIG_NET_CLS_ACT
 302 #ifdef CONFIG_NETFILTER
 303         if (!nf_registered) {
 304                 if (nf_register_hook(&ing_ops) < 0) {
 305                         printk("ingress qdisc registration error \n");
 306                         return -EINVAL;
 307                 }
 308                 nf_registered++;
 309
 310                 if (nf_register_hook(&ing6_ops) < 0) {
 311                         printk("IPv6 ingress qdisc registration error, " \
 312                             "disabling IPv6 support.\n");
 313                 } else
 314                         nf_registered++;
 315         }
 316 #endif
 317 #endif
 318
 319         DPRINTK("ingress_init(sch %p,[qdisc %p],opt %p)\n",sch,p,opt);
 320         p->q = &noop_qdisc;
 321         return 0;
 322 }
 323
 324
 325 static void ingress_reset(struct Qdisc *sch)
 326 {
 327         struct ingress_qdisc_data *p = PRIV(sch);
 328
 329         DPRINTK("ingress_reset(sch %p,[qdisc %p])\n", sch, p);
 330
 331 /*
 332 #if 0
 333 */
 334 /* for future use */
 335         qdisc_reset(p->q);
 336 /*
 337 #endif
 338 */
 339 }
 340
 341 /* ------------------------------------------------------------- */
 342
 343
 344 /* ------------------------------------------------------------- */
 345
 346 static void ingress_destroy(struct Qdisc *sch)
 347 {
 348         struct ingress_qdisc_data *p = PRIV(sch);
 349         struct tcf_proto *tp;
 350
 351         DPRINTK("ingress_destroy(sch %p,[qdisc %p])\n", sch, p);
 352         while (p->filter_list) {
 353                 tp = p->filter_list;
 354                 p->filter_list = tp->next;
 355                 tcf_destroy(tp);
 356         }
 357 #if 0
 358 /* for future use */
 359         qdisc_destroy(p->q);
 360 #endif
 361 }
 362
 363
 364 static int ingress_dump(struct Qdisc *sch, struct sk_buff *skb)
 365 {
 366         unsigned char *b = skb->tail;
 367         struct rtattr *rta;
 368
 369         rta = (struct rtattr *) b;
 370         RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 371         rta->rta_len = skb->tail - b;
 372         return skb->len;
 373
 374 rtattr_failure:
 375         skb_trim(skb, b - skb->data);
 376         return -1;
 377 }
 378
 379 static struct Qdisc_class_ops ingress_class_ops = {
 380         .graft          =       ingress_graft,
 381         .leaf           =       ingress_leaf,
 382         .get            =       ingress_get,
 383         .put            =       ingress_put,
 384         .change         =       ingress_change,
 385         .delete         =       NULL,
 386         .walk           =       ingress_walk,
 387         .tcf_chain      =       ingress_find_tcf,
 388         .bind_tcf       =       ingress_bind_filter,
 389         .unbind_tcf     =       ingress_put,
 390         .dump           =       NULL,
 391 };
 392
 393 static struct Qdisc_ops ingress_qdisc_ops = {
 394         .next           =       NULL,
 395         .cl_ops         =       &ingress_class_ops,
 396         .id             =       "ingress",
 397         .priv_size      =       sizeof(struct ingress_qdisc_data),
 398         .enqueue        =       ingress_enqueue,
 399         .dequeue        =       ingress_dequeue,
 400         .requeue        =       ingress_requeue,
 401         .drop           =       ingress_drop,
 402         .init           =       ingress_init,
 403         .reset          =       ingress_reset,
 404         .destroy        =       ingress_destroy,
 405         .change         =       NULL,
 406         .dump           =       ingress_dump,
 407         .owner          =       THIS_MODULE,
 408 };
 409
 410 static int __init ingress_module_init(void)
 411 {
 412         int ret = 0;
 413
 414         if ((ret = register_qdisc(&ingress_qdisc_ops)) < 0) {
 415                 printk("Unable to register Ingress qdisc\n");
 416                 return ret;
 417         }
 418
 419         return ret;
 420 }
 421 static void __exit ingress_module_exit(void)
 422 {
 423         unregister_qdisc(&ingress_qdisc_ops);
 424 #ifndef CONFIG_NET_CLS_ACT
 425 #ifdef CONFIG_NETFILTER
 426         if (nf_registered) {
 427                 nf_unregister_hook(&ing_ops);
 428                 if (nf_registered > 1)
 429                         nf_unregister_hook(&ing6_ops);
 430         }
 431 #endif
 432 #endif
 433 }
 434 module_init(ingress_module_init)
 435 module_exit(ingress_module_exit)
 436 MODULE_LICENSE("GPL");