net/sched/cls_fw.c

   1 /*
   2  * net/sched/cls_fw.c   Classifier mapping ipchains' fwmark to traffic class.
   3  *
   4  *              This program is free software; you can redistribute it and/or
   5  *              modify it under the terms of the GNU General Public License
   6  *              as published by the Free Software Foundation; either version
   7  *              2 of the License, or (at your option) any later version.
   8  *
   9  * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  10  *
  11  * Changes:
  12  * Karlis Peisenieks <karlis@mt.lv> : 990415 : fw_walk off by one
  13  * Karlis Peisenieks <karlis@mt.lv> : 990415 : fw_delete killed all the filter (and kernel).
  14  * Alex <alex@pilotsoft.com> : 2004xxyy: Added Action extension
  15  *
  16  * JHS: We should remove the CONFIG_NET_CLS_IND from here
  17  * eventually when the meta match extension is made available
  18  *
  19  */
  20
  21 #include <linux/module.h>
  22 #include <asm/uaccess.h>
  23 #include <asm/system.h>
  24 #include <linux/bitops.h>
  25 #include <linux/types.h>
  26 #include <linux/kernel.h>
  27 #include <linux/string.h>
  28 #include <linux/mm.h>
  29 #include <linux/socket.h>
  30 #include <linux/sockios.h>
  31 #include <linux/in.h>
  32 #include <linux/errno.h>
  33 #include <linux/interrupt.h>
  34 #include <linux/if_ether.h>
  35 #include <linux/inet.h>
  36 #include <linux/netdevice.h>
  37 #include <linux/etherdevice.h>
  38 #include <linux/notifier.h>
  39 #include <linux/netfilter.h>
  40 #include <net/ip.h>
  41 #include <net/route.h>
  42 #include <linux/skbuff.h>
  43 #include <net/sock.h>
  44 #include <net/act_api.h>
  45 #include <net/pkt_cls.h>
  46
  47 #define HTSIZE (PAGE_SIZE/sizeof(struct fw_filter *))
  48
  49 struct fw_head
  50 {
  51         struct fw_filter *ht[HTSIZE];
  52         u32 mask;
  53 };
  54
  55 struct fw_filter
  56 {
  57         struct fw_filter        *next;
  58         u32                     id;
  59         struct tcf_result       res;
  60 #ifdef CONFIG_NET_CLS_IND
  61         char                    indev[IFNAMSIZ];
  62 #endif /* CONFIG_NET_CLS_IND */
  63         struct tcf_exts         exts;
  64 };
  65
  66 static struct tcf_ext_map fw_ext_map = {
  67         .action = TCA_FW_ACT,
  68         .police = TCA_FW_POLICE
  69 };
  70
  71 static __inline__ int fw_hash(u32 handle)
  72 {
  73         if (HTSIZE == 4096)
  74                 return ((handle >> 24) & 0xFFF) ^
  75                        ((handle >> 12) & 0xFFF) ^
  76                        (handle & 0xFFF);
  77         else if (HTSIZE == 2048)
  78                 return ((handle >> 22) & 0x7FF) ^
  79                        ((handle >> 11) & 0x7FF) ^
  80                        (handle & 0x7FF);
  81         else if (HTSIZE == 1024)
  82                 return ((handle >> 20) & 0x3FF) ^
  83                        ((handle >> 10) & 0x3FF) ^
  84                        (handle & 0x3FF);
  85         else if (HTSIZE == 512)
  86                 return (handle >> 27) ^
  87                        ((handle >> 18) & 0x1FF) ^
  88                        ((handle >> 9) & 0x1FF) ^
  89                        (handle & 0x1FF);
  90         else if (HTSIZE == 256) {
  91                 u8 *t = (u8 *) &handle;
  92                 return t[0] ^ t[1] ^ t[2] ^ t[3];
  93         } else
  94                 return handle & (HTSIZE - 1);
  95 }
  96
  97 static int fw_classify(struct sk_buff *skb, struct tcf_proto *tp,
  98                           struct tcf_result *res)
  99 {
 100         struct fw_head *head = (struct fw_head*)tp->root;
 101         struct fw_filter *f;
 102         int r;
 103         u32 id = skb->mark;
 104
 105         if (head != NULL) {
 106                 id &= head->mask;
 107                 for (f=head->ht[fw_hash(id)]; f; f=f->next) {
 108                         if (f->id == id) {
 109                                 *res = f->res;
 110 #ifdef CONFIG_NET_CLS_IND
 111                                 if (!tcf_match_indev(skb, f->indev))
 112                                         continue;
 113 #endif /* CONFIG_NET_CLS_IND */
 114                                 r = tcf_exts_exec(skb, &f->exts, res);
 115                                 if (r < 0)
 116                                         continue;
 117
 118                                 return r;
 119                         }
 120                 }
 121         } else {
 122                 /* old method */
 123                 if (id && (TC_H_MAJ(id) == 0 || !(TC_H_MAJ(id^tp->q->handle)))) {
 124                         res->classid = id;
 125                         res->class = 0;
 126                         return 0;
 127                 }
 128         }
 129
 130         return -1;
 131 }
 132
 133 static unsigned long fw_get(struct tcf_proto *tp, u32 handle)
 134 {
 135         struct fw_head *head = (struct fw_head*)tp->root;
 136         struct fw_filter *f;
 137
 138         if (head == NULL)
 139                 return 0;
 140
 141         for (f=head->ht[fw_hash(handle)]; f; f=f->next) {
 142                 if (f->id == handle)
 143                         return (unsigned long)f;
 144         }
 145         return 0;
 146 }
 147
 148 static void fw_put(struct tcf_proto *tp, unsigned long f)
 149 {
 150 }
 151
 152 static int fw_init(struct tcf_proto *tp)
 153 {
 154         return 0;
 155 }
 156
 157 static inline void
 158 fw_delete_filter(struct tcf_proto *tp, struct fw_filter *f)
 159 {
 160         tcf_unbind_filter(tp, &f->res);
 161         tcf_exts_destroy(tp, &f->exts);
 162         kfree(f);
 163 }
 164
 165 static void fw_destroy(struct tcf_proto *tp)
 166 {
 167         struct fw_head *head = (struct fw_head*)xchg(&tp->root, NULL);
 168         struct fw_filter *f;
 169         int h;
 170
 171         if (head == NULL)
 172                 return;
 173
 174         for (h=0; h<HTSIZE; h++) {
 175                 while ((f=head->ht[h]) != NULL) {
 176                         head->ht[h] = f->next;
 177                         fw_delete_filter(tp, f);
 178                 }
 179         }
 180         kfree(head);
 181 }
 182
 183 static int fw_delete(struct tcf_proto *tp, unsigned long arg)
 184 {
 185         struct fw_head *head = (struct fw_head*)tp->root;
 186         struct fw_filter *f = (struct fw_filter*)arg;
 187         struct fw_filter **fp;
 188
 189         if (head == NULL || f == NULL)
 190                 goto out;
 191
 192         for (fp=&head->ht[fw_hash(f->id)]; *fp; fp = &(*fp)->next) {
 193                 if (*fp == f) {
 194                         tcf_tree_lock(tp);
 195                         *fp = f->next;
 196                         tcf_tree_unlock(tp);
 197                         fw_delete_filter(tp, f);
 198                         return 0;
 199                 }
 200         }
 201 out:
 202         return -EINVAL;
 203 }
 204
 205 static int
 206 fw_change_attrs(struct tcf_proto *tp, struct fw_filter *f,
 207         struct rtattr **tb, struct rtattr **tca, unsigned long base)
 208 {
 209         struct fw_head *head = (struct fw_head *)tp->root;
 210         struct tcf_exts e;
 211         u32 mask;
 212         int err;
 213
 214         err = tcf_exts_validate(tp, tb, tca[TCA_RATE-1], &e, &fw_ext_map);
 215         if (err < 0)
 216                 return err;
 217
 218         err = -EINVAL;
 219         if (tb[TCA_FW_CLASSID-1]) {
 220                 if (RTA_PAYLOAD(tb[TCA_FW_CLASSID-1]) != sizeof(u32))
 221                         goto errout;
 222                 f->res.classid = *(u32*)RTA_DATA(tb[TCA_FW_CLASSID-1]);
 223                 tcf_bind_filter(tp, &f->res, base);
 224         }
 225
 226 #ifdef CONFIG_NET_CLS_IND
 227         if (tb[TCA_FW_INDEV-1]) {
 228                 err = tcf_change_indev(tp, f->indev, tb[TCA_FW_INDEV-1]);
 229                 if (err < 0)
 230                         goto errout;
 231         }
 232 #endif /* CONFIG_NET_CLS_IND */
 233
 234         if (tb[TCA_FW_MASK-1]) {
 235                 if (RTA_PAYLOAD(tb[TCA_FW_MASK-1]) != sizeof(u32))
 236                         goto errout;
 237                 mask = *(u32*)RTA_DATA(tb[TCA_FW_MASK-1]);
 238                 if (mask != head->mask)
 239                         goto errout;
 240         } else if (head->mask != 0xFFFFFFFF)
 241                 goto errout;
 242
 243         tcf_exts_change(tp, &f->exts, &e);
 244
 245         return 0;
 246 errout:
 247         tcf_exts_destroy(tp, &e);
 248         return err;
 249 }
 250
 251 static int fw_change(struct tcf_proto *tp, unsigned long base,
 252                      u32 handle,
 253                      struct rtattr **tca,
 254                      unsigned long *arg)
 255 {
 256         struct fw_head *head = (struct fw_head*)tp->root;
 257         struct fw_filter *f = (struct fw_filter *) *arg;
 258         struct rtattr *opt = tca[TCA_OPTIONS-1];
 259         struct rtattr *tb[TCA_FW_MAX];
 260         int err;
 261
 262         if (!opt)
 263                 return handle ? -EINVAL : 0;
 264
 265         if (rtattr_parse_nested(tb, TCA_FW_MAX, opt) < 0)
 266                 return -EINVAL;
 267
 268         if (f != NULL) {
 269                 if (f->id != handle && handle)
 270                         return -EINVAL;
 271                 return fw_change_attrs(tp, f, tb, tca, base);
 272         }
 273
 274         if (!handle)
 275                 return -EINVAL;
 276
 277         if (head == NULL) {
 278                 u32 mask = 0xFFFFFFFF;
 279                 if (tb[TCA_FW_MASK-1]) {
 280                         if (RTA_PAYLOAD(tb[TCA_FW_MASK-1]) != sizeof(u32))
 281                                 return -EINVAL;
 282                         mask = *(u32*)RTA_DATA(tb[TCA_FW_MASK-1]);
 283                 }
 284
 285                 head = kzalloc(sizeof(struct fw_head), GFP_KERNEL);
 286                 if (head == NULL)
 287                         return -ENOBUFS;
 288                 head->mask = mask;
 289
 290                 tcf_tree_lock(tp);
 291                 tp->root = head;
 292                 tcf_tree_unlock(tp);
 293         }
 294
 295         f = kzalloc(sizeof(struct fw_filter), GFP_KERNEL);
 296         if (f == NULL)
 297                 return -ENOBUFS;
 298
 299         f->id = handle;
 300
 301         err = fw_change_attrs(tp, f, tb, tca, base);
 302         if (err < 0)
 303                 goto errout;
 304
 305         f->next = head->ht[fw_hash(handle)];
 306         tcf_tree_lock(tp);
 307         head->ht[fw_hash(handle)] = f;
 308         tcf_tree_unlock(tp);
 309
 310         *arg = (unsigned long)f;
 311         return 0;
 312
 313 errout:
 314         kfree(f);
 315         return err;
 316 }
 317
 318 static void fw_walk(struct tcf_proto *tp, struct tcf_walker *arg)
 319 {
 320         struct fw_head *head = (struct fw_head*)tp->root;
 321         int h;
 322
 323         if (head == NULL)
 324                 arg->stop = 1;
 325
 326         if (arg->stop)
 327                 return;
 328
 329         for (h = 0; h < HTSIZE; h++) {
 330                 struct fw_filter *f;
 331
 332                 for (f = head->ht[h]; f; f = f->next) {
 333                         if (arg->count < arg->skip) {
 334                                 arg->count++;
 335                                 continue;
 336                         }
 337                         if (arg->fn(tp, (unsigned long)f, arg) < 0) {
 338                                 arg->stop = 1;
 339                                 return;
 340                         }
 341                         arg->count++;
 342                 }
 343         }
 344 }
 345
 346 static int fw_dump(struct tcf_proto *tp, unsigned long fh,
 347                    struct sk_buff *skb, struct tcmsg *t)
 348 {
 349         struct fw_head *head = (struct fw_head *)tp->root;
 350         struct fw_filter *f = (struct fw_filter*)fh;
 351         unsigned char    *b = skb->tail;
 352         struct rtattr *rta;
 353
 354         if (f == NULL)
 355                 return skb->len;
 356
 357         t->tcm_handle = f->id;
 358
 359         if (!f->res.classid && !tcf_exts_is_available(&f->exts))
 360                 return skb->len;
 361
 362         rta = (struct rtattr*)b;
 363         RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 364
 365         if (f->res.classid)
 366                 RTA_PUT(skb, TCA_FW_CLASSID, 4, &f->res.classid);
 367 #ifdef CONFIG_NET_CLS_IND
 368         if (strlen(f->indev))
 369                 RTA_PUT(skb, TCA_FW_INDEV, IFNAMSIZ, f->indev);
 370 #endif /* CONFIG_NET_CLS_IND */
 371         if (head->mask != 0xFFFFFFFF)
 372                 RTA_PUT(skb, TCA_FW_MASK, 4, &head->mask);
 373
 374         if (tcf_exts_dump(skb, &f->exts, &fw_ext_map) < 0)
 375                 goto rtattr_failure;
 376
 377         rta->rta_len = skb->tail - b;
 378
 379         if (tcf_exts_dump_stats(skb, &f->exts, &fw_ext_map) < 0)
 380                 goto rtattr_failure;
 381
 382         return skb->len;
 383
 384 rtattr_failure:
 385         skb_trim(skb, b - skb->data);
 386         return -1;
 387 }
 388
 389 static struct tcf_proto_ops cls_fw_ops = {
 390         .next           =       NULL,
 391         .kind           =       "fw",
 392         .classify       =       fw_classify,
 393         .init           =       fw_init,
 394         .destroy        =       fw_destroy,
 395         .get            =       fw_get,
 396         .put            =       fw_put,
 397         .change         =       fw_change,
 398         .delete         =       fw_delete,
 399         .walk           =       fw_walk,
 400         .dump           =       fw_dump,
 401         .owner          =       THIS_MODULE,
 402 };
 403
 404 static int __init init_fw(void)
 405 {
 406         return register_tcf_proto_ops(&cls_fw_ops);
 407 }
 408
 409 static void __exit exit_fw(void)
 410 {
 411         unregister_tcf_proto_ops(&cls_fw_ops);
 412 }
 413
 414 module_init(init_fw)
 415 module_exit(exit_fw)
 416 MODULE_LICENSE("GPL");