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  */
  15
  16 #include <linux/config.h>
  17 #include <linux/module.h>
  18 #include <asm/uaccess.h>
  19 #include <asm/system.h>
  20 #include <asm/bitops.h>
  21 #include <linux/types.h>
  22 #include <linux/kernel.h>
  23 #include <linux/sched.h>
  24 #include <linux/string.h>
  25 #include <linux/mm.h>
  26 #include <linux/socket.h>
  27 #include <linux/sockios.h>
  28 #include <linux/in.h>
  29 #include <linux/errno.h>
  30 #include <linux/interrupt.h>
  31 #include <linux/if_ether.h>
  32 #include <linux/inet.h>
  33 #include <linux/netdevice.h>
  34 #include <linux/etherdevice.h>
  35 #include <linux/notifier.h>
  36 #include <linux/netfilter.h>
  37 #include <net/ip.h>
  38 #include <net/route.h>
  39 #include <linux/skbuff.h>
  40 #include <net/sock.h>
  41 #include <net/pkt_sched.h>
  42
  43 struct fw_head
  44 {
  45         struct fw_filter *ht[256];
  46 };
  47
  48 struct fw_filter
  49 {
  50         struct fw_filter        *next;
  51         u32                     id;
  52         struct tcf_result       res;
  53 #ifdef CONFIG_NET_CLS_POLICE
  54         struct tcf_police       *police;
  55 #endif
  56 };
  57
  58 static __inline__ int fw_hash(u32 handle)
  59 {
  60         return handle&0xFF;
  61 }
  62
  63 static int fw_classify(struct sk_buff *skb, struct tcf_proto *tp,
  64                           struct tcf_result *res)
  65 {
  66         struct fw_head *head = (struct fw_head*)tp->root;
  67         struct fw_filter *f;
  68 #ifdef CONFIG_NETFILTER
  69         u32 id = skb->nfmark;
  70 #else
  71         u32 id = 0;
  72 #endif
  73
  74         if (head == NULL)
  75                 goto old_method;
  76
  77         for (f=head->ht[fw_hash(id)]; f; f=f->next) {
  78                 if (f->id == id) {
  79                         *res = f->res;
  80 #ifdef CONFIG_NET_CLS_POLICE
  81                         if (f->police)
  82                                 return tcf_police(skb, f->police);
  83 #endif
  84                         return 0;
  85                 }
  86         }
  87         return -1;
  88
  89 old_method:
  90         if (id && (TC_H_MAJ(id) == 0 ||
  91                      !(TC_H_MAJ(id^tp->q->handle)))) {
  92                 res->classid = id;
  93                 res->class = 0;
  94                 return 0;
  95         }
  96         return -1;
  97 }
  98
  99 static unsigned long fw_get(struct tcf_proto *tp, u32 handle)
 100 {
 101         struct fw_head *head = (struct fw_head*)tp->root;
 102         struct fw_filter *f;
 103
 104         if (head == NULL)
 105                 return 0;
 106
 107         for (f=head->ht[fw_hash(handle)]; f; f=f->next) {
 108                 if (f->id == handle)
 109                         return (unsigned long)f;
 110         }
 111         return 0;
 112 }
 113
 114 static void fw_put(struct tcf_proto *tp, unsigned long f)
 115 {
 116 }
 117
 118 static int fw_init(struct tcf_proto *tp)
 119 {
 120         MOD_INC_USE_COUNT;
 121         return 0;
 122 }
 123
 124 static void fw_destroy(struct tcf_proto *tp)
 125 {
 126         struct fw_head *head = (struct fw_head*)xchg(&tp->root, NULL);
 127         struct fw_filter *f;
 128         int h;
 129
 130         if (head == NULL) {
 131                 MOD_DEC_USE_COUNT;
 132                 return;
 133         }
 134
 135         for (h=0; h<256; h++) {
 136                 while ((f=head->ht[h]) != NULL) {
 137                         unsigned long cl;
 138                         head->ht[h] = f->next;
 139
 140                         if ((cl = __cls_set_class(&f->res.class, 0)) != 0)
 141                                 tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
 142 #ifdef CONFIG_NET_CLS_POLICE
 143                         tcf_police_release(f->police);
 144 #endif
 145                         kfree(f);
 146                 }
 147         }
 148         kfree(head);
 149         MOD_DEC_USE_COUNT;
 150 }
 151
 152 static int fw_delete(struct tcf_proto *tp, unsigned long arg)
 153 {
 154         struct fw_head *head = (struct fw_head*)tp->root;
 155         struct fw_filter *f = (struct fw_filter*)arg;
 156         struct fw_filter **fp;
 157
 158         if (head == NULL || f == NULL)
 159                 return -EINVAL;
 160
 161         for (fp=&head->ht[fw_hash(f->id)]; *fp; fp = &(*fp)->next) {
 162                 if (*fp == f) {
 163                         unsigned long cl;
 164
 165                         tcf_tree_lock(tp);
 166                         *fp = f->next;
 167                         tcf_tree_unlock(tp);
 168
 169                         if ((cl = cls_set_class(tp, &f->res.class, 0)) != 0)
 170                                 tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
 171 #ifdef CONFIG_NET_CLS_POLICE
 172                         tcf_police_release(f->police);
 173 #endif
 174                         kfree(f);
 175                         return 0;
 176                 }
 177         }
 178         return -EINVAL;
 179 }
 180
 181 static int fw_change(struct tcf_proto *tp, unsigned long base,
 182                      u32 handle,
 183                      struct rtattr **tca,
 184                      unsigned long *arg)
 185 {
 186         struct fw_head *head = (struct fw_head*)tp->root;
 187         struct fw_filter *f;
 188         struct rtattr *opt = tca[TCA_OPTIONS-1];
 189         struct rtattr *tb[TCA_FW_MAX];
 190         int err;
 191
 192         if (!opt)
 193                 return handle ? -EINVAL : 0;
 194
 195         if (rtattr_parse(tb, TCA_FW_MAX, RTA_DATA(opt), RTA_PAYLOAD(opt)) < 0)
 196                 return -EINVAL;
 197
 198         if ((f = (struct fw_filter*)*arg) != NULL) {
 199                 /* Node exists: adjust only classid */
 200
 201                 if (f->id != handle && handle)
 202                         return -EINVAL;
 203                 if (tb[TCA_FW_CLASSID-1]) {
 204                         unsigned long cl;
 205
 206                         f->res.classid = *(u32*)RTA_DATA(tb[TCA_FW_CLASSID-1]);
 207                         cl = tp->q->ops->cl_ops->bind_tcf(tp->q, base, f->res.classid);
 208                         cl = cls_set_class(tp, &f->res.class, cl);
 209                         if (cl)
 210                                 tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
 211                 }
 212 #ifdef CONFIG_NET_CLS_POLICE
 213                 if (tb[TCA_FW_POLICE-1]) {
 214                         struct tcf_police *police = tcf_police_locate(tb[TCA_FW_POLICE-1], tca[TCA_RATE-1]);
 215
 216                         tcf_tree_lock(tp);
 217                         police = xchg(&f->police, police);
 218                         tcf_tree_unlock(tp);
 219
 220                         tcf_police_release(police);
 221                 }
 222 #endif
 223                 return 0;
 224         }
 225
 226         if (!handle)
 227                 return -EINVAL;
 228
 229         if (head == NULL) {
 230                 head = kmalloc(sizeof(struct fw_head), GFP_KERNEL);
 231                 if (head == NULL)
 232                         return -ENOBUFS;
 233                 memset(head, 0, sizeof(*head));
 234
 235                 tcf_tree_lock(tp);
 236                 tp->root = head;
 237                 tcf_tree_unlock(tp);
 238         }
 239
 240         f = kmalloc(sizeof(struct fw_filter), GFP_KERNEL);
 241         if (f == NULL)
 242                 return -ENOBUFS;
 243         memset(f, 0, sizeof(*f));
 244
 245         f->id = handle;
 246
 247         if (tb[TCA_FW_CLASSID-1]) {
 248                 err = -EINVAL;
 249                 if (RTA_PAYLOAD(tb[TCA_FW_CLASSID-1]) != 4)
 250                         goto errout;
 251                 f->res.classid = *(u32*)RTA_DATA(tb[TCA_FW_CLASSID-1]);
 252                 cls_set_class(tp, &f->res.class, tp->q->ops->cl_ops->bind_tcf(tp->q, base, f->res.classid));
 253         }
 254
 255 #ifdef CONFIG_NET_CLS_POLICE
 256         if (tb[TCA_FW_POLICE-1])
 257                 f->police = tcf_police_locate(tb[TCA_FW_POLICE-1], tca[TCA_RATE-1]);
 258 #endif
 259
 260         f->next = head->ht[fw_hash(handle)];
 261         tcf_tree_lock(tp);
 262         head->ht[fw_hash(handle)] = f;
 263         tcf_tree_unlock(tp);
 264
 265         *arg = (unsigned long)f;
 266         return 0;
 267
 268 errout:
 269         if (f)
 270                 kfree(f);
 271         return err;
 272 }
 273
 274 static void fw_walk(struct tcf_proto *tp, struct tcf_walker *arg)
 275 {
 276         struct fw_head *head = (struct fw_head*)tp->root;
 277         int h;
 278
 279         if (head == NULL)
 280                 arg->stop = 1;
 281
 282         if (arg->stop)
 283                 return;
 284
 285         for (h = 0; h < 256; h++) {
 286                 struct fw_filter *f;
 287
 288                 for (f = head->ht[h]; f; f = f->next) {
 289                         if (arg->count < arg->skip) {
 290                                 arg->count++;
 291                                 continue;
 292                         }
 293                         if (arg->fn(tp, (unsigned long)f, arg) < 0) {
 294                                 arg->stop = 1;
 295                                 break;
 296                         }
 297                         arg->count++;
 298                 }
 299         }
 300 }
 301
 302 #ifdef CONFIG_RTNETLINK
 303 static int fw_dump(struct tcf_proto *tp, unsigned long fh,
 304                    struct sk_buff *skb, struct tcmsg *t)
 305 {
 306         struct fw_filter *f = (struct fw_filter*)fh;
 307         unsigned char    *b = skb->tail;
 308         struct rtattr *rta;
 309
 310         if (f == NULL)
 311                 return skb->len;
 312
 313         t->tcm_handle = f->id;
 314
 315        if (!f->res.classid
 316 #ifdef CONFIG_NET_CLS_POLICE
 317            && !f->police
 318 #endif
 319            )
 320                 return skb->len;
 321
 322         rta = (struct rtattr*)b;
 323         RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 324
 325         if (f->res.classid)
 326                 RTA_PUT(skb, TCA_FW_CLASSID, 4, &f->res.classid);
 327 #ifdef CONFIG_NET_CLS_POLICE
 328         if (f->police) {
 329                 struct rtattr * p_rta = (struct rtattr*)skb->tail;
 330
 331                 RTA_PUT(skb, TCA_FW_POLICE, 0, NULL);
 332
 333                 if (tcf_police_dump(skb, f->police) < 0)
 334                         goto rtattr_failure;
 335
 336                 p_rta->rta_len = skb->tail - (u8*)p_rta;
 337         }
 338 #endif
 339
 340         rta->rta_len = skb->tail - b;
 341 #ifdef CONFIG_NET_CLS_POLICE
 342         if (f->police) {
 343                 if (qdisc_copy_stats(skb, &f->police->stats))
 344                         goto rtattr_failure;
 345         }
 346 #endif
 347         return skb->len;
 348
 349 rtattr_failure:
 350         skb_trim(skb, b - skb->data);
 351         return -1;
 352 }
 353 #endif
 354
 355
 356 struct tcf_proto_ops cls_fw_ops = {
 357         NULL,
 358         "fw",
 359         fw_classify,
 360         fw_init,
 361         fw_destroy,
 362
 363         fw_get,
 364         fw_put,
 365         fw_change,
 366         fw_delete,
 367         fw_walk,
 368 #ifdef CONFIG_RTNETLINK
 369         fw_dump
 370 #else
 371         NULL
 372 #endif
 373 };
 374
 375 #ifdef MODULE
 376 int init_module(void)
 377 {
 378         return register_tcf_proto_ops(&cls_fw_ops);
 379 }
 380
 381 void cleanup_module(void)
 382 {
 383         unregister_tcf_proto_ops(&cls_fw_ops);
 384 }
 385 #endif