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, <[email protected]>
  10  *
  11  * Changes:
  12  * Karlis Peisenieks <[email protected]> : 990415 : fw_walk off by one
  13  * Karlis Peisenieks <[email protected]> : 990415 : fw_delete killed all the filter (and kernel).
  14  * Alex <[email protected]> : 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 struct fw_head
  50 {
  51         struct fw_filter *ht[256];
  52 };
  53
  54 struct fw_filter
  55 {
  56         struct fw_filter        *next;
  57         u32                     id;
  58         struct tcf_result       res;
  59 #ifdef CONFIG_NET_CLS_IND
  60         char                    indev[IFNAMSIZ];
  61 #endif /* CONFIG_NET_CLS_IND */
  62         struct tcf_exts         exts;
  63 };
  64
  65 static struct tcf_ext_map fw_ext_map = {
  66         .action = TCA_FW_ACT,
  67         .police = TCA_FW_POLICE
  68 };
  69
  70 static __inline__ int fw_hash(u32 handle)
  71 {
  72         return handle&0xFF;
  73 }
  74
  75 static int fw_classify(struct sk_buff *skb, struct tcf_proto *tp,
  76                           struct tcf_result *res)
  77 {
  78         struct fw_head *head = (struct fw_head*)tp->root;
  79         struct fw_filter *f;
  80         int r;
  81 #ifdef CONFIG_NETFILTER
  82         u32 id = skb->nfmark;
  83 #else
  84         u32 id = 0;
  85 #endif
  86
  87         if (head != NULL) {
  88                 for (f=head->ht[fw_hash(id)]; f; f=f->next) {
  89                         if (f->id == id) {
  90                                 *res = f->res;
  91 #ifdef CONFIG_NET_CLS_IND
  92                                 if (!tcf_match_indev(skb, f->indev))
  93                                         continue;
  94 #endif /* CONFIG_NET_CLS_IND */
  95                                 r = tcf_exts_exec(skb, &f->exts, res);
  96                                 if (r < 0)
  97                                         continue;
  98
  99                                 return r;
 100                         }
 101                 }
 102         } else {
 103                 /* old method */
 104                 if (id && (TC_H_MAJ(id) == 0 || !(TC_H_MAJ(id^tp->q->handle)))) {
 105                         res->classid = id;
 106                         res->class = 0;
 107                         return 0;
 108                 }
 109         }
 110
 111         return -1;
 112 }
 113
 114 static unsigned long fw_get(struct tcf_proto *tp, u32 handle)
 115 {
 116         struct fw_head *head = (struct fw_head*)tp->root;
 117         struct fw_filter *f;
 118
 119         if (head == NULL)
 120                 return 0;
 121
 122         for (f=head->ht[fw_hash(handle)]; f; f=f->next) {
 123                 if (f->id == handle)
 124                         return (unsigned long)f;
 125         }
 126         return 0;
 127 }
 128
 129 static void fw_put(struct tcf_proto *tp, unsigned long f)
 130 {
 131 }
 132
 133 static int fw_init(struct tcf_proto *tp)
 134 {
 135         return 0;
 136 }
 137
 138 static inline void
 139 fw_delete_filter(struct tcf_proto *tp, struct fw_filter *f)
 140 {
 141         tcf_unbind_filter(tp, &f->res);
 142         tcf_exts_destroy(tp, &f->exts);
 143         kfree(f);
 144 }
 145
 146 static void fw_destroy(struct tcf_proto *tp)
 147 {
 148         struct fw_head *head = (struct fw_head*)xchg(&tp->root, NULL);
 149         struct fw_filter *f;
 150         int h;
 151
 152         if (head == NULL)
 153                 return;
 154
 155         for (h=0; h<256; h++) {
 156                 while ((f=head->ht[h]) != NULL) {
 157                         head->ht[h] = f->next;
 158                         fw_delete_filter(tp, f);
 159                 }
 160         }
 161         kfree(head);
 162 }
 163
 164 static int fw_delete(struct tcf_proto *tp, unsigned long arg)
 165 {
 166         struct fw_head *head = (struct fw_head*)tp->root;
 167         struct fw_filter *f = (struct fw_filter*)arg;
 168         struct fw_filter **fp;
 169
 170         if (head == NULL || f == NULL)
 171                 goto out;
 172
 173         for (fp=&head->ht[fw_hash(f->id)]; *fp; fp = &(*fp)->next) {
 174                 if (*fp == f) {
 175                         tcf_tree_lock(tp);
 176                         *fp = f->next;
 177                         tcf_tree_unlock(tp);
 178                         fw_delete_filter(tp, f);
 179                         return 0;
 180                 }
 181         }
 182 out:
 183         return -EINVAL;
 184 }
 185
 186 static int
 187 fw_change_attrs(struct tcf_proto *tp, struct fw_filter *f,
 188         struct rtattr **tb, struct rtattr **tca, unsigned long base)
 189 {
 190         struct tcf_exts e;
 191         int err;
 192
 193         err = tcf_exts_validate(tp, tb, tca[TCA_RATE-1], &e, &fw_ext_map);
 194         if (err < 0)
 195                 return err;
 196
 197         err = -EINVAL;
 198         if (tb[TCA_FW_CLASSID-1]) {
 199                 if (RTA_PAYLOAD(tb[TCA_FW_CLASSID-1]) != sizeof(u32))
 200                         goto errout;
 201                 f->res.classid = *(u32*)RTA_DATA(tb[TCA_FW_CLASSID-1]);
 202                 tcf_bind_filter(tp, &f->res, base);
 203         }
 204
 205 #ifdef CONFIG_NET_CLS_IND
 206         if (tb[TCA_FW_INDEV-1]) {
 207                 err = tcf_change_indev(tp, f->indev, tb[TCA_FW_INDEV-1]);
 208                 if (err < 0)
 209                         goto errout;
 210         }
 211 #endif /* CONFIG_NET_CLS_IND */
 212
 213         tcf_exts_change(tp, &f->exts, &e);
 214
 215         return 0;
 216 errout:
 217         tcf_exts_destroy(tp, &e);
 218         return err;
 219 }
 220
 221 static int fw_change(struct tcf_proto *tp, unsigned long base,
 222                      u32 handle,
 223                      struct rtattr **tca,
 224                      unsigned long *arg)
 225 {
 226         struct fw_head *head = (struct fw_head*)tp->root;
 227         struct fw_filter *f = (struct fw_filter *) *arg;
 228         struct rtattr *opt = tca[TCA_OPTIONS-1];
 229         struct rtattr *tb[TCA_FW_MAX];
 230         int err;
 231
 232         if (!opt)
 233                 return handle ? -EINVAL : 0;
 234
 235         if (rtattr_parse_nested(tb, TCA_FW_MAX, opt) < 0)
 236                 return -EINVAL;
 237
 238         if (f != NULL) {
 239                 if (f->id != handle && handle)
 240                         return -EINVAL;
 241                 return fw_change_attrs(tp, f, tb, tca, base);
 242         }
 243
 244         if (!handle)
 245                 return -EINVAL;
 246
 247         if (head == NULL) {
 248                 head = kmalloc(sizeof(struct fw_head), GFP_KERNEL);
 249                 if (head == NULL)
 250                         return -ENOBUFS;
 251                 memset(head, 0, sizeof(*head));
 252
 253                 tcf_tree_lock(tp);
 254                 tp->root = head;
 255                 tcf_tree_unlock(tp);
 256         }
 257
 258         f = kmalloc(sizeof(struct fw_filter), GFP_KERNEL);
 259         if (f == NULL)
 260                 return -ENOBUFS;
 261         memset(f, 0, sizeof(*f));
 262
 263         f->id = handle;
 264
 265         err = fw_change_attrs(tp, f, tb, tca, base);
 266         if (err < 0)
 267                 goto errout;
 268
 269         f->next = head->ht[fw_hash(handle)];
 270         tcf_tree_lock(tp);
 271         head->ht[fw_hash(handle)] = f;
 272         tcf_tree_unlock(tp);
 273
 274         *arg = (unsigned long)f;
 275         return 0;
 276
 277 errout:
 278         if (f)
 279                 kfree(f);
 280         return err;
 281 }
 282
 283 static void fw_walk(struct tcf_proto *tp, struct tcf_walker *arg)
 284 {
 285         struct fw_head *head = (struct fw_head*)tp->root;
 286         int h;
 287
 288         if (head == NULL)
 289                 arg->stop = 1;
 290
 291         if (arg->stop)
 292                 return;
 293
 294         for (h = 0; h < 256; h++) {
 295                 struct fw_filter *f;
 296
 297                 for (f = head->ht[h]; f; f = f->next) {
 298                         if (arg->count < arg->skip) {
 299                                 arg->count++;
 300                                 continue;
 301                         }
 302                         if (arg->fn(tp, (unsigned long)f, arg) < 0) {
 303                                 arg->stop = 1;
 304                                 return;
 305                         }
 306                         arg->count++;
 307                 }
 308         }
 309 }
 310
 311 static int fw_dump(struct tcf_proto *tp, unsigned long fh,
 312                    struct sk_buff *skb, struct tcmsg *t)
 313 {
 314         struct fw_filter *f = (struct fw_filter*)fh;
 315         unsigned char    *b = skb->tail;
 316         struct rtattr *rta;
 317
 318         if (f == NULL)
 319                 return skb->len;
 320
 321         t->tcm_handle = f->id;
 322
 323         if (!f->res.classid && !tcf_exts_is_available(&f->exts))
 324                 return skb->len;
 325
 326         rta = (struct rtattr*)b;
 327         RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 328
 329         if (f->res.classid)
 330                 RTA_PUT(skb, TCA_FW_CLASSID, 4, &f->res.classid);
 331 #ifdef CONFIG_NET_CLS_IND
 332         if (strlen(f->indev))
 333                 RTA_PUT(skb, TCA_FW_INDEV, IFNAMSIZ, f->indev);
 334 #endif /* CONFIG_NET_CLS_IND */
 335
 336         if (tcf_exts_dump(skb, &f->exts, &fw_ext_map) < 0)
 337                 goto rtattr_failure;
 338
 339         rta->rta_len = skb->tail - b;
 340
 341         if (tcf_exts_dump_stats(skb, &f->exts, &fw_ext_map) < 0)
 342                 goto rtattr_failure;
 343
 344         return skb->len;
 345
 346 rtattr_failure:
 347         skb_trim(skb, b - skb->data);
 348         return -1;
 349 }
 350
 351 static struct tcf_proto_ops cls_fw_ops = {
 352         .next           =       NULL,
 353         .kind           =       "fw",
 354         .classify       =       fw_classify,
 355         .init           =       fw_init,
 356         .destroy        =       fw_destroy,
 357         .get            =       fw_get,
 358         .put            =       fw_put,
 359         .change         =       fw_change,
 360         .delete         =       fw_delete,
 361         .walk           =       fw_walk,
 362         .dump           =       fw_dump,
 363         .owner          =       THIS_MODULE,
 364 };
 365
 366 static int __init init_fw(void)
 367 {
 368         return register_tcf_proto_ops(&cls_fw_ops);
 369 }
 370
 371 static void __exit exit_fw(void)
 372 {
 373         unregister_tcf_proto_ops(&cls_fw_ops);
 374 }
 375
 376 module_init(init_fw)
 377 module_exit(exit_fw)
 378 MODULE_LICENSE("GPL");