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