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