net/sched1/sch_dsmark.c

   1 /* net/sched/sch_dsmark.c - Differentiated Services field marker */
   2
   3 /* Written 1998-2000 by Werner Almesberger, EPFL ICA */
   4
   5
   6 #include <linux/config.h>
   7 #include <linux/module.h>
   8 #include <linux/types.h>
   9 #include <linux/string.h>
  10 #include <linux/errno.h>
  11 #include <linux/skbuff.h>
  12 #include <linux/netdevice.h> /* for pkt_sched */
  13 #include <linux/rtnetlink.h>
  14 #include <net/pkt_sched.h>
  15 #include <net/dsfield.h>
  16 #include <asm/byteorder.h>
  17
  18
  19 #if 1 /* control */
  20 #define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
  21 #else
  22 #define DPRINTK(format,args...)
  23 #endif
  24
  25 #if 0 /* data */
  26 #define D2PRINTK(format,args...) printk(KERN_DEBUG format,##args)
  27 #else
  28 #define D2PRINTK(format,args...)
  29 #endif
  30
  31
  32 #define PRIV(sch) ((struct dsmark_qdisc_data *) (sch)->data)
  33
  34
  35 /*
  36  * classid      class           marking
  37  * -------      -----           -------
  38  *   n/a          0             n/a
  39  *   x:0          1             use entry [0]
  40  *   ...         ...            ...
  41  *   x:y y>0     y+1            use entry [y]
  42  *   ...         ...            ...
  43  * x:indices-1  indices         use entry [indices-1]
  44  *   ...         ...            ...
  45  *   x:y         y+1            use entry [y & (indices-1)]
  46  *   ...         ...            ...
  47  * 0xffff       0x10000         use entry [indices-1]
  48  */
  49
  50
  51 #define NO_DEFAULT_INDEX        (1 << 16)
  52
  53 struct dsmark_qdisc_data {
  54         struct Qdisc            *q;
  55         struct tcf_proto        *filter_list;
  56         __u8                    *mask;  /* "owns" the array */
  57         __u8                    *value;
  58         __u16                   indices;
  59         __u32                   default_index;  /* index range is 0...0xffff */
  60         int                     set_tc_index;
  61 };
  62
  63
  64 /* ------------------------- Class/flow operations ------------------------- */
  65
  66
  67 static int dsmark_graft(struct Qdisc *sch,unsigned long arg,
  68     struct Qdisc *new,struct Qdisc **old)
  69 {
  70         struct dsmark_qdisc_data *p = PRIV(sch);
  71
  72         DPRINTK("dsmark_graft(sch %p,[qdisc %p],new %p,old %p)\n",sch,p,new,
  73             old);
  74         if (!new)
  75                 new = &noop_qdisc;
  76         sch_tree_lock(sch);
  77         *old = xchg(&p->q,new);
  78         if (*old)
  79                 qdisc_reset(*old);
  80         sch_tree_unlock(sch); /* @@@ move up ? */
  81         return 0;
  82 }
  83
  84
  85 static struct Qdisc *dsmark_leaf(struct Qdisc *sch, unsigned long arg)
  86 {
  87         struct dsmark_qdisc_data *p = PRIV(sch);
  88
  89         return p->q;
  90 }
  91
  92
  93 static unsigned long dsmark_get(struct Qdisc *sch,u32 classid)
  94 {
  95         struct dsmark_qdisc_data *p __attribute__((unused)) = PRIV(sch);
  96
  97         DPRINTK("dsmark_get(sch %p,[qdisc %p],classid %x)\n",sch,p,classid);
  98         return TC_H_MIN(classid)+1;
  99 }
 100
 101
 102 static unsigned long dsmark_bind_filter(struct Qdisc *sch,
 103     unsigned long parent, u32 classid)
 104 {
 105         return dsmark_get(sch,classid);
 106 }
 107
 108
 109 static void dsmark_put(struct Qdisc *sch, unsigned long cl)
 110 {
 111 }
 112
 113
 114 static int dsmark_change(struct Qdisc *sch, u32 classid, u32 parent,
 115     struct rtattr **tca, unsigned long *arg)
 116 {
 117         struct dsmark_qdisc_data *p = PRIV(sch);
 118         struct rtattr *opt = tca[TCA_OPTIONS-1];
 119         struct rtattr *tb[TCA_DSMARK_MAX];
 120
 121         DPRINTK("dsmark_change(sch %p,[qdisc %p],classid %x,parent %x),"
 122             "arg 0x%lx\n",sch,p,classid,parent,*arg);
 123         if (*arg > p->indices)
 124                 return -ENOENT;
 125         if (!opt || rtattr_parse(tb, TCA_DSMARK_MAX, RTA_DATA(opt),
 126                                  RTA_PAYLOAD(opt)))
 127                 return -EINVAL;
 128         if (tb[TCA_DSMARK_MASK-1]) {
 129                 if (!RTA_PAYLOAD(tb[TCA_DSMARK_MASK-1]))
 130                         return -EINVAL;
 131                 p->mask[*arg-1] = *(__u8 *) RTA_DATA(tb[TCA_DSMARK_MASK-1]);
 132         }
 133         if (tb[TCA_DSMARK_VALUE-1]) {
 134                 if (!RTA_PAYLOAD(tb[TCA_DSMARK_VALUE-1]))
 135                         return -EINVAL;
 136                 p->value[*arg-1] = *(__u8 *) RTA_DATA(tb[TCA_DSMARK_VALUE-1]);
 137         }
 138         return 0;
 139 }
 140
 141
 142 static int dsmark_delete(struct Qdisc *sch,unsigned long arg)
 143 {
 144         struct dsmark_qdisc_data *p = PRIV(sch);
 145
 146         if (!arg || arg > p->indices)
 147                 return -EINVAL;
 148         p->mask[arg-1] = 0xff;
 149         p->value[arg-1] = 0;
 150         return 0;
 151 }
 152
 153
 154 static void dsmark_walk(struct Qdisc *sch,struct qdisc_walker *walker)
 155 {
 156         struct dsmark_qdisc_data *p = PRIV(sch);
 157         int i;
 158
 159         DPRINTK("dsmark_walk(sch %p,[qdisc %p],walker %p)\n",sch,p,walker);
 160         if (walker->stop)
 161                 return;
 162         for (i = 0; i < p->indices; i++) {
 163                 if (p->mask[i] == 0xff && !p->value[i])
 164                         continue;
 165                 if (walker->count >= walker->skip) {
 166                         if (walker->fn(sch, i+1, walker) < 0) {
 167                                 walker->stop = 1;
 168                                 break;
 169                         }
 170                 }
 171                 walker->count++;
 172         }
 173 }
 174
 175
 176 static struct tcf_proto **dsmark_find_tcf(struct Qdisc *sch,unsigned long cl)
 177 {
 178         struct dsmark_qdisc_data *p = PRIV(sch);
 179
 180         return &p->filter_list;
 181 }
 182
 183
 184 /* --------------------------- Qdisc operations ---------------------------- */
 185
 186
 187 static int dsmark_enqueue(struct sk_buff *skb,struct Qdisc *sch)
 188 {
 189         struct dsmark_qdisc_data *p = PRIV(sch);
 190         struct tcf_result res;
 191         int result;
 192         int ret = NET_XMIT_POLICED;
 193
 194         D2PRINTK("dsmark_enqueue(skb %p,sch %p,[qdisc %p])\n",skb,sch,p);
 195         if (p->set_tc_index) {
 196                 switch (skb->protocol) {
 197                         case __constant_htons(ETH_P_IP):
 198                                 skb->tc_index = ipv4_get_dsfield(skb->nh.iph);
 199                                 break;
 200                         case __constant_htons(ETH_P_IPV6):
 201                                 skb->tc_index = ipv6_get_dsfield(skb->nh.ipv6h);
 202                                 break;
 203                         default:
 204                                 skb->tc_index = 0;
 205                                 break;
 206                 };
 207         }
 208         result = TC_POLICE_OK; /* be nice to gcc */
 209         if (TC_H_MAJ(skb->priority) == sch->handle) {
 210                 skb->tc_index = TC_H_MIN(skb->priority);
 211         } else {
 212                 result = tc_classify(skb,p->filter_list,&res);
 213                 D2PRINTK("result %d class 0x%04x\n",result,res.classid);
 214                 switch (result) {
 215 #ifdef CONFIG_NET_CLS_POLICE
 216                         case TC_POLICE_SHOT:
 217                                 kfree_skb(skb);
 218                                 break;
 219 #if 0
 220                         case TC_POLICE_RECLASSIFY:
 221                                 /* FIXME: what to do here ??? */
 222 #endif
 223 #endif
 224                         case TC_POLICE_OK:
 225                                 skb->tc_index = TC_H_MIN(res.classid);
 226                                 break;
 227                         case TC_POLICE_UNSPEC:
 228                                 /* fall through */
 229                         default:
 230                                 if (p->default_index != NO_DEFAULT_INDEX)
 231                                         skb->tc_index = p->default_index;
 232                                 break;
 233                 };
 234         }
 235         if (
 236 #ifdef CONFIG_NET_CLS_POLICE
 237             result == TC_POLICE_SHOT ||
 238 #endif
 239
 240             ((ret = p->q->enqueue(skb,p->q)) != 0)) {
 241                 sch->stats.drops++;
 242                 return ret;
 243         }
 244         sch->stats.bytes += skb->len;
 245         sch->stats.packets++;
 246         sch->q.qlen++;
 247         return ret;
 248 }
 249
 250
 251 static struct sk_buff *dsmark_dequeue(struct Qdisc *sch)
 252 {
 253         struct dsmark_qdisc_data *p = PRIV(sch);
 254         struct sk_buff *skb;
 255         int index;
 256
 257         D2PRINTK("dsmark_dequeue(sch %p,[qdisc %p])\n",sch,p);
 258         skb = p->q->ops->dequeue(p->q);
 259         if (!skb)
 260                 return NULL;
 261         sch->q.qlen--;
 262         index = skb->tc_index & (p->indices-1);
 263         D2PRINTK("index %d->%d\n",skb->tc_index,index);
 264         switch (skb->protocol) {
 265                 case __constant_htons(ETH_P_IP):
 266                         ipv4_change_dsfield(skb->nh.iph,
 267                             p->mask[index],p->value[index]);
 268                         break;
 269                 case __constant_htons(ETH_P_IPV6):
 270                         ipv6_change_dsfield(skb->nh.ipv6h,
 271                             p->mask[index],p->value[index]);
 272                         break;
 273                 default:
 274                         /*
 275                          * Only complain if a change was actually attempted.
 276                          * This way, we can send non-IP traffic through dsmark
 277                          * and don't need yet another qdisc as a bypass.
 278                          */
 279                         if (p->mask[index] != 0xff || p->value[index])
 280                                 printk(KERN_WARNING "dsmark_dequeue: "
 281                                        "unsupported protocol %d\n",
 282                                        htons(skb->protocol));
 283                         break;
 284         };
 285         return skb;
 286 }
 287
 288
 289 static int dsmark_requeue(struct sk_buff *skb,struct Qdisc *sch)
 290 {
 291         int ret;
 292         struct dsmark_qdisc_data *p = PRIV(sch);
 293
 294         D2PRINTK("dsmark_requeue(skb %p,sch %p,[qdisc %p])\n",skb,sch,p);
 295         if ((ret = p->q->ops->requeue(skb, p->q)) == 0) {
 296                 sch->q.qlen++;
 297                 return 0;
 298         }
 299         sch->stats.drops++;
 300         return ret;
 301 }
 302
 303
 304 static int dsmark_drop(struct Qdisc *sch)
 305 {
 306         struct dsmark_qdisc_data *p = PRIV(sch);
 307
 308         DPRINTK("dsmark_reset(sch %p,[qdisc %p])\n",sch,p);
 309         if (!p->q->ops->drop)
 310                 return 0;
 311         if (!p->q->ops->drop(p->q))
 312                 return 0;
 313         sch->q.qlen--;
 314         return 1;
 315 }
 316
 317
 318 int dsmark_init(struct Qdisc *sch,struct rtattr *opt)
 319 {
 320         struct dsmark_qdisc_data *p = PRIV(sch);
 321         struct rtattr *tb[TCA_DSMARK_MAX];
 322         __u16 tmp;
 323
 324         DPRINTK("dsmark_init(sch %p,[qdisc %p],opt %p)\n",sch,p,opt);
 325         if (rtattr_parse(tb,TCA_DSMARK_MAX,RTA_DATA(opt),RTA_PAYLOAD(opt)) < 0 ||
 326             !tb[TCA_DSMARK_INDICES-1] ||
 327             RTA_PAYLOAD(tb[TCA_DSMARK_INDICES-1]) < sizeof(__u16))
 328                 return -EINVAL;
 329         memset(p,0,sizeof(*p));
 330         p->filter_list = NULL;
 331         p->indices = *(__u16 *) RTA_DATA(tb[TCA_DSMARK_INDICES-1]);
 332         if (!p->indices)
 333                 return -EINVAL;
 334         for (tmp = p->indices; tmp != 1; tmp >>= 1) {
 335                 if (tmp & 1)
 336                         return -EINVAL;
 337         }
 338         p->default_index = NO_DEFAULT_INDEX;
 339         if (tb[TCA_DSMARK_DEFAULT_INDEX-1]) {
 340                 if (RTA_PAYLOAD(tb[TCA_DSMARK_DEFAULT_INDEX-1]) < sizeof(__u16))
 341                         return -EINVAL;
 342                 p->default_index =
 343                     *(__u16 *) RTA_DATA(tb[TCA_DSMARK_DEFAULT_INDEX-1]);
 344         }
 345         p->set_tc_index = !!tb[TCA_DSMARK_SET_TC_INDEX-1];
 346         p->mask = kmalloc(p->indices*2,GFP_KERNEL);
 347         if (!p->mask)
 348                 return -ENOMEM;
 349         p->value = p->mask+p->indices;
 350         memset(p->mask,0xff,p->indices);
 351         memset(p->value,0,p->indices);
 352         if (!(p->q = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops)))
 353                 p->q = &noop_qdisc;
 354         DPRINTK("dsmark_init: qdisc %p\n",&p->q);
 355         MOD_INC_USE_COUNT;
 356         return 0;
 357 }
 358
 359
 360 static void dsmark_reset(struct Qdisc *sch)
 361 {
 362         struct dsmark_qdisc_data *p = PRIV(sch);
 363
 364         DPRINTK("dsmark_reset(sch %p,[qdisc %p])\n",sch,p);
 365         qdisc_reset(p->q);
 366         sch->q.qlen = 0;
 367 }
 368
 369
 370 static void dsmark_destroy(struct Qdisc *sch)
 371 {
 372         struct dsmark_qdisc_data *p = PRIV(sch);
 373         struct tcf_proto *tp;
 374
 375         DPRINTK("dsmark_destroy(sch %p,[qdisc %p])\n",sch,p);
 376         while (p->filter_list) {
 377                 tp = p->filter_list;
 378                 p->filter_list = tp->next;
 379                 tp->ops->destroy(tp);
 380         }
 381         qdisc_destroy(p->q);
 382         p->q = &noop_qdisc;
 383         kfree(p->mask);
 384         MOD_DEC_USE_COUNT;
 385 }
 386
 387
 388 static int dsmark_dump_class(struct Qdisc *sch, unsigned long cl,
 389     struct sk_buff *skb, struct tcmsg *tcm)
 390 {
 391         struct dsmark_qdisc_data *p = PRIV(sch);
 392         unsigned char *b = skb->tail;
 393         struct rtattr *rta;
 394
 395         DPRINTK("dsmark_dump_class(sch %p,[qdisc %p],class %ld\n",sch,p,cl);
 396         if (!cl || cl > p->indices)
 397                 return -EINVAL;
 398         tcm->tcm_handle = TC_H_MAKE(TC_H_MAJ(sch->handle),cl-1);
 399         rta = (struct rtattr *) b;
 400         RTA_PUT(skb,TCA_OPTIONS,0,NULL);
 401         RTA_PUT(skb,TCA_DSMARK_MASK,1,&p->mask[cl-1]);
 402         RTA_PUT(skb,TCA_DSMARK_VALUE,1,&p->value[cl-1]);
 403         rta->rta_len = skb->tail-b;
 404         return skb->len;
 405
 406 rtattr_failure:
 407         skb_trim(skb,b-skb->data);
 408         return -1;
 409 }
 410
 411 static int dsmark_dump(struct Qdisc *sch, struct sk_buff *skb)
 412 {
 413         struct dsmark_qdisc_data *p = PRIV(sch);
 414         unsigned char *b = skb->tail;
 415         struct rtattr *rta;
 416
 417         rta = (struct rtattr *) b;
 418         RTA_PUT(skb,TCA_OPTIONS,0,NULL);
 419         RTA_PUT(skb,TCA_DSMARK_INDICES,sizeof(__u16),&p->indices);
 420         if (p->default_index != NO_DEFAULT_INDEX) {
 421                 __u16 tmp = p->default_index;
 422
 423                 RTA_PUT(skb,TCA_DSMARK_DEFAULT_INDEX, sizeof(__u16), &tmp);
 424         }
 425         if (p->set_tc_index)
 426                 RTA_PUT(skb, TCA_DSMARK_SET_TC_INDEX, 0, NULL);
 427         rta->rta_len = skb->tail-b;
 428         return skb->len;
 429
 430 rtattr_failure:
 431         skb_trim(skb,b-skb->data);
 432         return -1;
 433 }
 434
 435 static struct Qdisc_class_ops dsmark_class_ops =
 436 {
 437         dsmark_graft,                   /* graft */
 438         dsmark_leaf,                    /* leaf */
 439         dsmark_get,                     /* get */
 440         dsmark_put,                     /* put */
 441         dsmark_change,                  /* change */
 442         dsmark_delete,                  /* delete */
 443         dsmark_walk,                    /* walk */
 444
 445         dsmark_find_tcf,                /* tcf_chain */
 446         dsmark_bind_filter,             /* bind_tcf */
 447         dsmark_put,                     /* unbind_tcf */
 448
 449         dsmark_dump_class,              /* dump */
 450 };
 451
 452 struct Qdisc_ops dsmark_qdisc_ops =
 453 {
 454         NULL,                           /* next */
 455         &dsmark_class_ops,              /* cl_ops */
 456         "dsmark",
 457         sizeof(struct dsmark_qdisc_data),
 458
 459         dsmark_enqueue,                 /* enqueue */
 460         dsmark_dequeue,                 /* dequeue */
 461         dsmark_requeue,                 /* requeue */
 462         dsmark_drop,                    /* drop */
 463
 464         dsmark_init,                    /* init */
 465         dsmark_reset,                   /* reset */
 466         dsmark_destroy,                 /* destroy */
 467         NULL,                           /* change */
 468
 469         dsmark_dump                     /* dump */
 470 };
 471
 472 #ifdef MODULE
 473 int init_module(void)
 474 {
 475         return register_qdisc(&dsmark_qdisc_ops);
 476 }
 477
 478
 479 void cleanup_module(void)
 480 {
 481         unregister_qdisc(&dsmark_qdisc_ops);
 482 }
 483 #endif
 484 MODULE_LICENSE("GPL");