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         return 0;
 121 }
 122
 123 static void fw_destroy(struct tcf_proto *tp)
 124 {
 125         struct fw_head *head = (struct fw_head*)xchg(&tp->root, NULL);
 126         struct fw_filter *f;
 127         int h;
 128
 129         if (head == NULL)
 130                 return;
 131
 132         for (h=0; h<256; h++) {
 133                 while ((f=head->ht[h]) != NULL) {
 134                         unsigned long cl;
 135                         head->ht[h] = f->next;
 136
 137                         if ((cl = __cls_set_class(&f->res.class, 0)) != 0)
 138                                 tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
 139 #ifdef CONFIG_NET_CLS_POLICE
 140                         tcf_police_release(f->police);
 141 #endif
 142                         kfree(f);
 143                 }
 144         }
 145         kfree(head);
 146 }
 147
 148 static int fw_delete(struct tcf_proto *tp, unsigned long arg)
 149 {
 150         struct fw_head *head = (struct fw_head*)tp->root;
 151         struct fw_filter *f = (struct fw_filter*)arg;
 152         struct fw_filter **fp;
 153
 154         if (head == NULL || f == NULL)
 155                 goto out;
 156
 157         for (fp=&head->ht[fw_hash(f->id)]; *fp; fp = &(*fp)->next) {
 158                 if (*fp == f) {
 159                         unsigned long cl;
 160
 161                         tcf_tree_lock(tp);
 162                         *fp = f->next;
 163                         tcf_tree_unlock(tp);
 164
 165                         if ((cl = cls_set_class(tp, &f->res.class, 0)) != 0)
 166                                 tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
 167 #ifdef CONFIG_NET_CLS_POLICE
 168                         tcf_police_release(f->police);
 169 #endif
 170                         kfree(f);
 171                         return 0;
 172                 }
 173         }
 174 out:
 175         return -EINVAL;
 176 }
 177
 178 static int fw_change(struct tcf_proto *tp, unsigned long base,
 179                      u32 handle,
 180                      struct rtattr **tca,
 181                      unsigned long *arg)
 182 {
 183         struct fw_head *head = (struct fw_head*)tp->root;
 184         struct fw_filter *f;
 185         struct rtattr *opt = tca[TCA_OPTIONS-1];
 186         struct rtattr *tb[TCA_FW_MAX];
 187         int err;
 188
 189         if (!opt)
 190                 return handle ? -EINVAL : 0;
 191
 192         if (rtattr_parse(tb, TCA_FW_MAX, RTA_DATA(opt), RTA_PAYLOAD(opt)) < 0)
 193                 return -EINVAL;
 194
 195         if ((f = (struct fw_filter*)*arg) != NULL) {
 196                 /* Node exists: adjust only classid */
 197
 198                 if (f->id != handle && handle)
 199                         return -EINVAL;
 200                 if (tb[TCA_FW_CLASSID-1]) {
 201                         unsigned long cl;
 202
 203                         f->res.classid = *(u32*)RTA_DATA(tb[TCA_FW_CLASSID-1]);
 204                         cl = tp->q->ops->cl_ops->bind_tcf(tp->q, base, f->res.classid);
 205                         cl = cls_set_class(tp, &f->res.class, cl);
 206                         if (cl)
 207                                 tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
 208                 }
 209 #ifdef CONFIG_NET_CLS_POLICE
 210                 if (tb[TCA_FW_POLICE-1]) {
 211                         struct tcf_police *police = tcf_police_locate(tb[TCA_FW_POLICE-1], tca[TCA_RATE-1]);
 212
 213                         tcf_tree_lock(tp);
 214                         police = xchg(&f->police, police);
 215                         tcf_tree_unlock(tp);
 216
 217                         tcf_police_release(police);
 218                 }
 219 #endif
 220                 return 0;
 221         }
 222
 223         if (!handle)
 224                 return -EINVAL;
 225
 226         if (head == NULL) {
 227                 head = kmalloc(sizeof(struct fw_head), GFP_KERNEL);
 228                 if (head == NULL)
 229                         return -ENOBUFS;
 230                 memset(head, 0, sizeof(*head));
 231
 232                 tcf_tree_lock(tp);
 233                 tp->root = head;
 234                 tcf_tree_unlock(tp);
 235         }
 236
 237         f = kmalloc(sizeof(struct fw_filter), GFP_KERNEL);
 238         if (f == NULL)
 239                 return -ENOBUFS;
 240         memset(f, 0, sizeof(*f));
 241
 242         f->id = handle;
 243
 244         if (tb[TCA_FW_CLASSID-1]) {
 245                 err = -EINVAL;
 246                 if (RTA_PAYLOAD(tb[TCA_FW_CLASSID-1]) != 4)
 247                         goto errout;
 248                 f->res.classid = *(u32*)RTA_DATA(tb[TCA_FW_CLASSID-1]);
 249                 cls_set_class(tp, &f->res.class, tp->q->ops->cl_ops->bind_tcf(tp->q, base, f->res.classid));
 250         }
 251
 252 #ifdef CONFIG_NET_CLS_POLICE
 253         if (tb[TCA_FW_POLICE-1])
 254                 f->police = tcf_police_locate(tb[TCA_FW_POLICE-1], tca[TCA_RATE-1]);
 255 #endif
 256
 257         f->next = head->ht[fw_hash(handle)];
 258         tcf_tree_lock(tp);
 259         head->ht[fw_hash(handle)] = f;
 260         tcf_tree_unlock(tp);
 261
 262         *arg = (unsigned long)f;
 263         return 0;
 264
 265 errout:
 266         if (f)
 267                 kfree(f);
 268         return err;
 269 }
 270
 271 static void fw_walk(struct tcf_proto *tp, struct tcf_walker *arg)
 272 {
 273         struct fw_head *head = (struct fw_head*)tp->root;
 274         int h;
 275
 276         if (head == NULL)
 277                 arg->stop = 1;
 278
 279         if (arg->stop)
 280                 return;
 281
 282         for (h = 0; h < 256; h++) {
 283                 struct fw_filter *f;
 284
 285                 for (f = head->ht[h]; f; f = f->next) {
 286                         if (arg->count < arg->skip) {
 287                                 arg->count++;
 288                                 continue;
 289                         }
 290                         if (arg->fn(tp, (unsigned long)f, arg) < 0) {
 291                                 arg->stop = 1;
 292                                 break;
 293                         }
 294                         arg->count++;
 295                 }
 296         }
 297 }
 298
 299 static int fw_dump(struct tcf_proto *tp, unsigned long fh,
 300                    struct sk_buff *skb, struct tcmsg *t)
 301 {
 302         struct fw_filter *f = (struct fw_filter*)fh;
 303         unsigned char    *b = skb->tail;
 304         struct rtattr *rta;
 305
 306         if (f == NULL)
 307                 return skb->len;
 308
 309         t->tcm_handle = f->id;
 310
 311        if (!f->res.classid
 312 #ifdef CONFIG_NET_CLS_POLICE
 313            && !f->police
 314 #endif
 315            )
 316                 return skb->len;
 317
 318         rta = (struct rtattr*)b;
 319         RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 320
 321         if (f->res.classid)
 322                 RTA_PUT(skb, TCA_FW_CLASSID, 4, &f->res.classid);
 323 #ifdef CONFIG_NET_CLS_POLICE
 324         if (f->police) {
 325                 struct rtattr * p_rta = (struct rtattr*)skb->tail;
 326
 327                 RTA_PUT(skb, TCA_FW_POLICE, 0, NULL);
 328
 329                 if (tcf_police_dump(skb, f->police) < 0)
 330                         goto rtattr_failure;
 331
 332                 p_rta->rta_len = skb->tail - (u8*)p_rta;
 333         }
 334 #endif
 335
 336         rta->rta_len = skb->tail - b;
 337 #ifdef CONFIG_NET_CLS_POLICE
 338         if (f->police) {
 339                 if (qdisc_copy_stats(skb, &f->police->stats))
 340                         goto rtattr_failure;
 341         }
 342 #endif
 343         return skb->len;
 344
 345 rtattr_failure:
 346         skb_trim(skb, b - skb->data);
 347         return -1;
 348 }
 349
 350 static struct tcf_proto_ops cls_fw_ops = {
 351         .next           =       NULL,
 352         .kind           =       "fw",
 353         .classify       =       fw_classify,
 354         .init           =       fw_init,
 355         .destroy        =       fw_destroy,
 356         .get            =       fw_get,
 357         .put            =       fw_put,
 358         .change         =       fw_change,
 359         .delete         =       fw_delete,
 360         .walk           =       fw_walk,
 361         .dump           =       fw_dump,
 362         .owner          =       THIS_MODULE,
 363 };
 364
 365 static int __init init_fw(void)
 366 {
 367         return register_tcf_proto_ops(&cls_fw_ops);
 368 }
 369
 370 static void __exit exit_fw(void)
 371 {
 372         unregister_tcf_proto_ops(&cls_fw_ops);
 373 }
 374
 375 module_init(init_fw)
 376 module_exit(exit_fw)
 377 MODULE_LICENSE("GPL");