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/sched.h>
  28 #include <linux/string.h>
  29 #include <linux/mm.h>
  30 #include <linux/socket.h>
  31 #include <linux/sockios.h>
  32 #include <linux/in.h>
  33 #include <linux/errno.h>
  34 #include <linux/interrupt.h>
  35 #include <linux/if_ether.h>
  36 #include <linux/inet.h>
  37 #include <linux/netdevice.h>
  38 #include <linux/etherdevice.h>
  39 #include <linux/notifier.h>
  40 #include <linux/netfilter.h>
  41 #include <net/ip.h>
  42 #include <net/route.h>
  43 #include <linux/skbuff.h>
  44 #include <net/sock.h>
  45 #include <net/act_api.h>
  46 #include <net/pkt_cls.h>
  47
  48 #define HTSIZE (PAGE_SIZE/sizeof(struct fw_filter *))
  49
  50 struct fw_head
  51 {
  52         struct fw_filter *ht[HTSIZE];
  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 #ifdef CONFIG_NETFILTER
 104         u32 id = skb->nfmark;
 105 #else
 106         u32 id = 0;
 107 #endif
 108
 109         if (head != NULL) {
 110                 for (f=head->ht[fw_hash(id)]; f; f=f->next) {
 111                         if (f->id == id) {
 112                                 *res = f->res;
 113 #ifdef CONFIG_NET_CLS_IND
 114                                 if (!tcf_match_indev(skb, f->indev))
 115                                         continue;
 116 #endif /* CONFIG_NET_CLS_IND */
 117                                 r = tcf_exts_exec(skb, &f->exts, res);
 118                                 if (r < 0)
 119                                         continue;
 120
 121                                 return r;
 122                         }
 123                 }
 124         } else {
 125                 /* old method */
 126                 if (id && (TC_H_MAJ(id) == 0 || !(TC_H_MAJ(id^tp->q->handle)))) {
 127                         res->classid = id;
 128                         res->class = 0;
 129                         return 0;
 130                 }
 131         }
 132
 133         return -1;
 134 }
 135
 136 static unsigned long fw_get(struct tcf_proto *tp, u32 handle)
 137 {
 138         struct fw_head *head = (struct fw_head*)tp->root;
 139         struct fw_filter *f;
 140
 141         if (head == NULL)
 142                 return 0;
 143
 144         for (f=head->ht[fw_hash(handle)]; f; f=f->next) {
 145                 if (f->id == handle)
 146                         return (unsigned long)f;
 147         }
 148         return 0;
 149 }
 150
 151 static void fw_put(struct tcf_proto *tp, unsigned long f)
 152 {
 153 }
 154
 155 static int fw_init(struct tcf_proto *tp)
 156 {
 157         return 0;
 158 }
 159
 160 static inline void
 161 fw_delete_filter(struct tcf_proto *tp, struct fw_filter *f)
 162 {
 163         tcf_unbind_filter(tp, &f->res);
 164         tcf_exts_destroy(tp, &f->exts);
 165         kfree(f);
 166 }
 167
 168 static void fw_destroy(struct tcf_proto *tp)
 169 {
 170         struct fw_head *head = (struct fw_head*)xchg(&tp->root, NULL);
 171         struct fw_filter *f;
 172         int h;
 173
 174         if (head == NULL)
 175                 return;
 176
 177         for (h=0; h<HTSIZE; h++) {
 178                 while ((f=head->ht[h]) != NULL) {
 179                         head->ht[h] = f->next;
 180                         fw_delete_filter(tp, f);
 181                 }
 182         }
 183         kfree(head);
 184 }
 185
 186 static int fw_delete(struct tcf_proto *tp, unsigned long arg)
 187 {
 188         struct fw_head *head = (struct fw_head*)tp->root;
 189         struct fw_filter *f = (struct fw_filter*)arg;
 190         struct fw_filter **fp;
 191
 192         if (head == NULL || f == NULL)
 193                 goto out;
 194
 195         for (fp=&head->ht[fw_hash(f->id)]; *fp; fp = &(*fp)->next) {
 196                 if (*fp == f) {
 197                         tcf_tree_lock(tp);
 198                         *fp = f->next;
 199                         tcf_tree_unlock(tp);
 200                         fw_delete_filter(tp, f);
 201                         return 0;
 202                 }
 203         }
 204 out:
 205         return -EINVAL;
 206 }
 207
 208 static int
 209 fw_change_attrs(struct tcf_proto *tp, struct fw_filter *f,
 210         struct rtattr **tb, struct rtattr **tca, unsigned long base)
 211 {
 212         struct tcf_exts e;
 213         int err;
 214
 215         err = tcf_exts_validate(tp, tb, tca[TCA_RATE-1], &e, &fw_ext_map);
 216         if (err < 0)
 217                 return err;
 218
 219         err = -EINVAL;
 220         if (tb[TCA_FW_CLASSID-1]) {
 221                 if (RTA_PAYLOAD(tb[TCA_FW_CLASSID-1]) != sizeof(u32))
 222                         goto errout;
 223                 f->res.classid = *(u32*)RTA_DATA(tb[TCA_FW_CLASSID-1]);
 224                 tcf_bind_filter(tp, &f->res, base);
 225         }
 226
 227 #ifdef CONFIG_NET_CLS_IND
 228         if (tb[TCA_FW_INDEV-1]) {
 229                 err = tcf_change_indev(tp, f->indev, tb[TCA_FW_INDEV-1]);
 230                 if (err < 0)
 231                         goto errout;
 232         }
 233 #endif /* CONFIG_NET_CLS_IND */
 234
 235         tcf_exts_change(tp, &f->exts, &e);
 236
 237         return 0;
 238 errout:
 239         tcf_exts_destroy(tp, &e);
 240         return err;
 241 }
 242
 243 static int fw_change(struct tcf_proto *tp, unsigned long base,
 244                      u32 handle,
 245                      struct rtattr **tca,
 246                      unsigned long *arg)
 247 {
 248         struct fw_head *head = (struct fw_head*)tp->root;
 249         struct fw_filter *f = (struct fw_filter *) *arg;
 250         struct rtattr *opt = tca[TCA_OPTIONS-1];
 251         struct rtattr *tb[TCA_FW_MAX];
 252         int err;
 253
 254         if (!opt)
 255                 return handle ? -EINVAL : 0;
 256
 257         if (rtattr_parse_nested(tb, TCA_FW_MAX, opt) < 0)
 258                 return -EINVAL;
 259
 260         if (f != NULL) {
 261                 if (f->id != handle && handle)
 262                         return -EINVAL;
 263                 return fw_change_attrs(tp, f, tb, tca, base);
 264         }
 265
 266         if (!handle)
 267                 return -EINVAL;
 268
 269         if (head == NULL) {
 270                 head = kmalloc(sizeof(struct fw_head), GFP_KERNEL);
 271                 if (head == NULL)
 272                         return -ENOBUFS;
 273                 memset(head, 0, sizeof(*head));
 274
 275                 tcf_tree_lock(tp);
 276                 tp->root = head;
 277                 tcf_tree_unlock(tp);
 278         }
 279
 280         f = kmalloc(sizeof(struct fw_filter), GFP_KERNEL);
 281         if (f == NULL)
 282                 return -ENOBUFS;
 283         memset(f, 0, sizeof(*f));
 284
 285         f->id = handle;
 286
 287         err = fw_change_attrs(tp, f, tb, tca, base);
 288         if (err < 0)
 289                 goto errout;
 290
 291         f->next = head->ht[fw_hash(handle)];
 292         tcf_tree_lock(tp);
 293         head->ht[fw_hash(handle)] = f;
 294         tcf_tree_unlock(tp);
 295
 296         *arg = (unsigned long)f;
 297         return 0;
 298
 299 errout:
 300         kfree(f);
 301         return err;
 302 }
 303
 304 static void fw_walk(struct tcf_proto *tp, struct tcf_walker *arg)
 305 {
 306         struct fw_head *head = (struct fw_head*)tp->root;
 307         int h;
 308
 309         if (head == NULL)
 310                 arg->stop = 1;
 311
 312         if (arg->stop)
 313                 return;
 314
 315         for (h = 0; h < HTSIZE; h++) {
 316                 struct fw_filter *f;
 317
 318                 for (f = head->ht[h]; f; f = f->next) {
 319                         if (arg->count < arg->skip) {
 320                                 arg->count++;
 321                                 continue;
 322                         }
 323                         if (arg->fn(tp, (unsigned long)f, arg) < 0) {
 324                                 arg->stop = 1;
 325                                 return;
 326                         }
 327                         arg->count++;
 328                 }
 329         }
 330 }
 331
 332 static int fw_dump(struct tcf_proto *tp, unsigned long fh,
 333                    struct sk_buff *skb, struct tcmsg *t)
 334 {
 335         struct fw_filter *f = (struct fw_filter*)fh;
 336         unsigned char    *b = skb->tail;
 337         struct rtattr *rta;
 338
 339         if (f == NULL)
 340                 return skb->len;
 341
 342         t->tcm_handle = f->id;
 343
 344         if (!f->res.classid && !tcf_exts_is_available(&f->exts))
 345                 return skb->len;
 346
 347         rta = (struct rtattr*)b;
 348         RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 349
 350         if (f->res.classid)
 351                 RTA_PUT(skb, TCA_FW_CLASSID, 4, &f->res.classid);
 352 #ifdef CONFIG_NET_CLS_IND
 353         if (strlen(f->indev))
 354                 RTA_PUT(skb, TCA_FW_INDEV, IFNAMSIZ, f->indev);
 355 #endif /* CONFIG_NET_CLS_IND */
 356
 357         if (tcf_exts_dump(skb, &f->exts, &fw_ext_map) < 0)
 358                 goto rtattr_failure;
 359
 360         rta->rta_len = skb->tail - b;
 361
 362         if (tcf_exts_dump_stats(skb, &f->exts, &fw_ext_map) < 0)
 363                 goto rtattr_failure;
 364
 365         return skb->len;
 366
 367 rtattr_failure:
 368         skb_trim(skb, b - skb->data);
 369         return -1;
 370 }
 371
 372 static struct tcf_proto_ops cls_fw_ops = {
 373         .next           =       NULL,
 374         .kind           =       "fw",
 375         .classify       =       fw_classify,
 376         .init           =       fw_init,
 377         .destroy        =       fw_destroy,
 378         .get            =       fw_get,
 379         .put            =       fw_put,
 380         .change         =       fw_change,
 381         .delete         =       fw_delete,
 382         .walk           =       fw_walk,
 383         .dump           =       fw_dump,
 384         .owner          =       THIS_MODULE,
 385 };
 386
 387 static int __init init_fw(void)
 388 {
 389         return register_tcf_proto_ops(&cls_fw_ops);
 390 }
 391
 392 static void __exit exit_fw(void)
 393 {
 394         unregister_tcf_proto_ops(&cls_fw_ops);
 395 }
 396
 397 module_init(init_fw)
 398 module_exit(exit_fw)
 399 MODULE_LICENSE("GPL");