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/netlink.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         u32 mask;
  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         u32 id = skb->mark;
 105
 106         if (head != NULL) {
 107                 id &= head->mask;
 108                 for (f=head->ht[fw_hash(id)]; f; f=f->next) {
 109                         if (f->id == id) {
 110                                 *res = f->res;
 111 #ifdef CONFIG_NET_CLS_IND
 112                                 if (!tcf_match_indev(skb, f->indev))
 113                                         continue;
 114 #endif /* CONFIG_NET_CLS_IND */
 115                                 r = tcf_exts_exec(skb, &f->exts, res);
 116                                 if (r < 0)
 117                                         continue;
 118
 119                                 return r;
 120                         }
 121                 }
 122         } else {
 123                 /* old method */
 124                 if (id && (TC_H_MAJ(id) == 0 || !(TC_H_MAJ(id^tp->q->handle)))) {
 125                         res->classid = id;
 126                         res->class = 0;
 127                         return 0;
 128                 }
 129         }
 130
 131         return -1;
 132 }
 133
 134 static unsigned long fw_get(struct tcf_proto *tp, u32 handle)
 135 {
 136         struct fw_head *head = (struct fw_head*)tp->root;
 137         struct fw_filter *f;
 138
 139         if (head == NULL)
 140                 return 0;
 141
 142         for (f=head->ht[fw_hash(handle)]; f; f=f->next) {
 143                 if (f->id == handle)
 144                         return (unsigned long)f;
 145         }
 146         return 0;
 147 }
 148
 149 static void fw_put(struct tcf_proto *tp, unsigned long f)
 150 {
 151 }
 152
 153 static int fw_init(struct tcf_proto *tp)
 154 {
 155         return 0;
 156 }
 157
 158 static inline void
 159 fw_delete_filter(struct tcf_proto *tp, struct fw_filter *f)
 160 {
 161         tcf_unbind_filter(tp, &f->res);
 162         tcf_exts_destroy(tp, &f->exts);
 163         kfree(f);
 164 }
 165
 166 static void fw_destroy(struct tcf_proto *tp)
 167 {
 168         struct fw_head *head = (struct fw_head*)xchg(&tp->root, NULL);
 169         struct fw_filter *f;
 170         int h;
 171
 172         if (head == NULL)
 173                 return;
 174
 175         for (h=0; h<HTSIZE; h++) {
 176                 while ((f=head->ht[h]) != NULL) {
 177                         head->ht[h] = f->next;
 178                         fw_delete_filter(tp, f);
 179                 }
 180         }
 181         kfree(head);
 182 }
 183
 184 static int fw_delete(struct tcf_proto *tp, unsigned long arg)
 185 {
 186         struct fw_head *head = (struct fw_head*)tp->root;
 187         struct fw_filter *f = (struct fw_filter*)arg;
 188         struct fw_filter **fp;
 189
 190         if (head == NULL || f == NULL)
 191                 goto out;
 192
 193         for (fp=&head->ht[fw_hash(f->id)]; *fp; fp = &(*fp)->next) {
 194                 if (*fp == f) {
 195                         tcf_tree_lock(tp);
 196                         *fp = f->next;
 197                         tcf_tree_unlock(tp);
 198                         fw_delete_filter(tp, f);
 199                         return 0;
 200                 }
 201         }
 202 out:
 203         return -EINVAL;
 204 }
 205
 206 static int
 207 fw_change_attrs(struct tcf_proto *tp, struct fw_filter *f,
 208         struct rtattr **tb, struct rtattr **tca, unsigned long base)
 209 {
 210         struct fw_head *head = (struct fw_head *)tp->root;
 211         struct tcf_exts e;
 212         u32 mask;
 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         if (tb[TCA_FW_MASK-1]) {
 236                 if (RTA_PAYLOAD(tb[TCA_FW_MASK-1]) != sizeof(u32))
 237                         goto errout;
 238                 mask = *(u32*)RTA_DATA(tb[TCA_FW_MASK-1]);
 239                 if (mask != head->mask)
 240                         goto errout;
 241         } else if (head->mask != 0xFFFFFFFF)
 242                 goto errout;
 243
 244         tcf_exts_change(tp, &f->exts, &e);
 245
 246         return 0;
 247 errout:
 248         tcf_exts_destroy(tp, &e);
 249         return err;
 250 }
 251
 252 static int fw_change(struct tcf_proto *tp, unsigned long base,
 253                      u32 handle,
 254                      struct rtattr **tca,
 255                      unsigned long *arg)
 256 {
 257         struct fw_head *head = (struct fw_head*)tp->root;
 258         struct fw_filter *f = (struct fw_filter *) *arg;
 259         struct rtattr *opt = tca[TCA_OPTIONS-1];
 260         struct rtattr *tb[TCA_FW_MAX];
 261         int err;
 262
 263         if (!opt)
 264                 return handle ? -EINVAL : 0;
 265
 266         if (rtattr_parse_nested(tb, TCA_FW_MAX, opt) < 0)
 267                 return -EINVAL;
 268
 269         if (f != NULL) {
 270                 if (f->id != handle && handle)
 271                         return -EINVAL;
 272                 return fw_change_attrs(tp, f, tb, tca, base);
 273         }
 274
 275         if (!handle)
 276                 return -EINVAL;
 277
 278         if (head == NULL) {
 279                 u32 mask = 0xFFFFFFFF;
 280                 if (tb[TCA_FW_MASK-1]) {
 281                         if (RTA_PAYLOAD(tb[TCA_FW_MASK-1]) != sizeof(u32))
 282                                 return -EINVAL;
 283                         mask = *(u32*)RTA_DATA(tb[TCA_FW_MASK-1]);
 284                 }
 285
 286                 head = kzalloc(sizeof(struct fw_head), GFP_KERNEL);
 287                 if (head == NULL)
 288                         return -ENOBUFS;
 289                 head->mask = mask;
 290
 291                 tcf_tree_lock(tp);
 292                 tp->root = head;
 293                 tcf_tree_unlock(tp);
 294         }
 295
 296         f = kzalloc(sizeof(struct fw_filter), GFP_KERNEL);
 297         if (f == NULL)
 298                 return -ENOBUFS;
 299
 300         f->id = handle;
 301
 302         err = fw_change_attrs(tp, f, tb, tca, base);
 303         if (err < 0)
 304                 goto errout;
 305
 306         f->next = head->ht[fw_hash(handle)];
 307         tcf_tree_lock(tp);
 308         head->ht[fw_hash(handle)] = f;
 309         tcf_tree_unlock(tp);
 310
 311         *arg = (unsigned long)f;
 312         return 0;
 313
 314 errout:
 315         kfree(f);
 316         return err;
 317 }
 318
 319 static void fw_walk(struct tcf_proto *tp, struct tcf_walker *arg)
 320 {
 321         struct fw_head *head = (struct fw_head*)tp->root;
 322         int h;
 323
 324         if (head == NULL)
 325                 arg->stop = 1;
 326
 327         if (arg->stop)
 328                 return;
 329
 330         for (h = 0; h < HTSIZE; h++) {
 331                 struct fw_filter *f;
 332
 333                 for (f = head->ht[h]; f; f = f->next) {
 334                         if (arg->count < arg->skip) {
 335                                 arg->count++;
 336                                 continue;
 337                         }
 338                         if (arg->fn(tp, (unsigned long)f, arg) < 0) {
 339                                 arg->stop = 1;
 340                                 return;
 341                         }
 342                         arg->count++;
 343                 }
 344         }
 345 }
 346
 347 static int fw_dump(struct tcf_proto *tp, unsigned long fh,
 348                    struct sk_buff *skb, struct tcmsg *t)
 349 {
 350         struct fw_head *head = (struct fw_head *)tp->root;
 351         struct fw_filter *f = (struct fw_filter*)fh;
 352         unsigned char *b = skb_tail_pointer(skb);
 353         struct rtattr *rta;
 354
 355         if (f == NULL)
 356                 return skb->len;
 357
 358         t->tcm_handle = f->id;
 359
 360         if (!f->res.classid && !tcf_exts_is_available(&f->exts))
 361                 return skb->len;
 362
 363         rta = (struct rtattr*)b;
 364         RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 365
 366         if (f->res.classid)
 367                 RTA_PUT(skb, TCA_FW_CLASSID, 4, &f->res.classid);
 368 #ifdef CONFIG_NET_CLS_IND
 369         if (strlen(f->indev))
 370                 RTA_PUT(skb, TCA_FW_INDEV, IFNAMSIZ, f->indev);
 371 #endif /* CONFIG_NET_CLS_IND */
 372         if (head->mask != 0xFFFFFFFF)
 373                 RTA_PUT(skb, TCA_FW_MASK, 4, &head->mask);
 374
 375         if (tcf_exts_dump(skb, &f->exts, &fw_ext_map) < 0)
 376                 goto rtattr_failure;
 377
 378         rta->rta_len = skb_tail_pointer(skb) - b;
 379
 380         if (tcf_exts_dump_stats(skb, &f->exts, &fw_ext_map) < 0)
 381                 goto rtattr_failure;
 382
 383         return skb->len;
 384
 385 rtattr_failure:
 386         nlmsg_trim(skb, b);
 387         return -1;
 388 }
 389
 390 static struct tcf_proto_ops cls_fw_ops = {
 391         .next           =       NULL,
 392         .kind           =       "fw",
 393         .classify       =       fw_classify,
 394         .init           =       fw_init,
 395         .destroy        =       fw_destroy,
 396         .get            =       fw_get,
 397         .put            =       fw_put,
 398         .change         =       fw_change,
 399         .delete         =       fw_delete,
 400         .walk           =       fw_walk,
 401         .dump           =       fw_dump,
 402         .owner          =       THIS_MODULE,
 403 };
 404
 405 static int __init init_fw(void)
 406 {
 407         return register_tcf_proto_ops(&cls_fw_ops);
 408 }
 409
 410 static void __exit exit_fw(void)
 411 {
 412         unregister_tcf_proto_ops(&cls_fw_ops);
 413 }
 414
 415 module_init(init_fw)
 416 module_exit(exit_fw)
 417 MODULE_LICENSE("GPL");