release/src-rt/linux/linux-2.6/net/ipv4/netfilter/ipt_account.c

   1 /* Copyright (c) 2004-2011 Piotr 'QuakeR' Gasidlo <quaker@barbara.eu.org>
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License version 2 as
   5  * published by the Free Software Foundation.
   6  */
   7
   8 #include <linux/version.h>
   9 #include <linux/module.h>
  10 #include <linux/skbuff.h>
  11 #include <linux/vmalloc.h>
  12 #include <linux/proc_fs.h>
  13 #include <linux/seq_file.h>
  14 #include <linux/time.h>
  15 #include <linux/ip.h>
  16 #include <linux/in.h>
  17
  18 #define IPT_ACCOUNT_VERSION "0.1.21"
  19
  20 //#define DEBUG_IPT_ACCOUNT
  21
  22 MODULE_AUTHOR("Piotr Gasidlo <quaker@barbara.eu.org>");
  23 MODULE_DESCRIPTION("Traffic accounting module");
  24 MODULE_LICENSE("GPL");
  25
  26 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,21)
  27 #include <linux/netfilter/x_tables.h>
  28 #else
  29 #include <linux/netfilter_ipv4/ip_tables.h>
  30 #endif
  31 #include <linux/netfilter_ipv4/ipt_account.h>
  32
  33 /* Compatibility, should replace all HIPQUAD with %pI4 and use network byte order not host byte order */
  34 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,30)
  35 #define HIPQUAD(addr) \
  36        ((unsigned char *)&addr)[3], \
  37        ((unsigned char *)&addr)[2], \
  38        ((unsigned char *)&addr)[1], \
  39        ((unsigned char *)&addr)[0]
  40 #endif
  41
  42 /* defaults, can be overriden */
  43 static unsigned int netmask = 16; /* Safe netmask, if you try to create table
  44                                      for larger netblock you will get error.
  45                                      Increase by command line only when you
  46                                      known what are you doing. */
  47
  48 #ifdef DEBUG_IPT_ACCOUNT
  49 static int debug = 0;
  50 #endif
  51 module_param(netmask, uint, 0400);
  52
  53 MODULE_PARM_DESC(netmask,"maximum *save* netmask");
  54 #ifdef DEBUG_IPT_ACCOUNT
  55 module_param(debug, bool, 0600);
  56 MODULE_PARM_DESC(debug,"enable debugging output");
  57 #endif
  58
  59 /* structure with statistics counter, used when table is created without --ashort switch */
  60 struct t_ipt_account_stat_long {
  61   u_int64_t b_all, b_tcp, b_udp, b_icmp, b_other;
  62   u_int64_t p_all, p_tcp, p_udp, p_icmp, p_other;
  63 };
  64
  65 /* same as above, for tables created with --ashort switch */
  66 struct t_ipt_account_stat_short {
  67   u_int64_t b_all;
  68   u_int64_t p_all;
  69 };
  70
  71 /* structure holding to/from statistics for single ip when table is created without --ashort switch */
  72 struct t_ipt_account_stats_long {
  73   struct t_ipt_account_stat_long src, dst;
  74   struct timespec time; /* time, when statistics was last modified */
  75 };
  76
  77 /* same as above, for tables created with --ashort switch */
  78 struct t_ipt_account_stats_short {
  79   struct t_ipt_account_stat_short src, dst;
  80   struct timespec time;
  81 };
  82
  83 /* defines for "show" table option */
  84 #define SHOW_ANY 0
  85 #define SHOW_SRC 1
  86 #define SHOW_DST 2
  87 #define SHOW_SRC_OR_DST 3
  88 #define SHOW_SRC_AND_DST 4
  89
  90 /* structure describing single table */
  91 struct t_ipt_account_table {
  92   struct list_head list;
  93   atomic_t use; /* use counter, the number of rules which points to this table */
  94
  95   char name[IPT_ACCOUNT_NAME_LEN + 1]; /* table name ( = filename in /proc/net/ipt_account/) */
  96   u_int32_t network, netmask, count; /* network/netmask/hosts count coverted by table */
  97
  98   int shortlisting:1; /* gather only total statistics (set for tables created with --ashort switch) */
  99   int timesrc:1; /* update time when accounting outgoing traffic */
 100   int timedst:1; /* update time when accounting incomming traffic */
 101   int resetonread:1; /* reset statistics after reading it via proc */
 102   int show; /* show with entries */
 103
 104   /* FIXME: why int show:3 results in 'warning: comparison is always 0 due to width of bit-field' in ipt_account_seq_show
 105    * gcc -v: gcc version 3.4.6 */
 106
 107   union { /* statistics for each ip in network/netmask */
 108     struct t_ipt_account_stats_long *l;
 109     struct t_ipt_account_stats_short *s;
 110   } stats;
 111   rwlock_t stats_lock; /* lock, to assure that above union can be safely modified */
 112
 113   struct proc_dir_entry *pde; /* handle to proc entry */
 114 };
 115
 116 static LIST_HEAD(ipt_account_tables);
 117 static rwlock_t ipt_account_lock = RW_LOCK_UNLOCKED; /* lock, to assure that table list can be safely modified */
 118 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,28)
 119 static DEFINE_MUTEX(ipt_account_mutex); /* additional checkentry protection */
 120 #else
 121 static DECLARE_MUTEX(ipt_account_mutex); /* additional checkentry protection */
 122 #endif
 123
 124 static struct file_operations ipt_account_proc_fops;
 125 static struct proc_dir_entry *ipt_account_procdir;
 126
 127 /*
 128  * Function creates new table and inserts it into linked list.
 129  */
 130 static struct t_ipt_account_table *
 131 ipt_account_table_init(struct t_ipt_account_info *info)
 132 {
 133   struct t_ipt_account_table *table;
 134
 135 #ifdef DEBUG_IPT_ACCOUNT
 136   if (debug) printk(KERN_DEBUG "ipt_account [ipt_account_table_init]: name = %s\n", info->name);
 137 #endif
 138
 139   /*
 140    * Allocate memory for table.
 141    */
 142   table = vmalloc(sizeof(struct t_ipt_account_table));
 143   if (!table) {
 144     printk(KERN_ERR "ipt_account [ipt_account_table_init]: table = vmalloc(sizeof(struct t_ipt_account_table)) failed.\n");
 145     goto cleanup_none;
 146   }
 147   memset(table, 0, sizeof(struct t_ipt_account_table));
 148
 149   /*
 150    * Table attributes.
 151    */
 152   strncpy(table->name, info->name, IPT_ACCOUNT_NAME_LEN);
 153   table->name[IPT_ACCOUNT_NAME_LEN] = '\0';
 154
 155   table->network = info->network;
 156   table->netmask = info->netmask;
 157   table->count = (0xffffffff ^ table->netmask) + 1;
 158
 159   /*
 160    * Table properties.
 161    */
 162   table->shortlisting = info->shortlisting;
 163   table->timesrc = 1;
 164   table->timedst = 1;
 165   table->resetonread = 0;
 166   table->show = SHOW_ANY;
 167
 168   /*
 169    * Initialize use counter.
 170    */
 171   atomic_set(&table->use, 1);
 172
 173   /*
 174    * Allocate memory for statistic counters.
 175    */
 176   if (table->shortlisting) {
 177     table->stats.s = vmalloc(sizeof(struct t_ipt_account_stats_short) * table->count);
 178     if (!table->stats.s) {
 179       printk(KERN_ERR "ipt_account [ipt_account_table_init]: table->stats.s = vmalloc(sizeof(struct t_ipt_account_stats_short) * table->count) failed.\n");
 180       goto cleanup_table;
 181     }
 182     memset(table->stats.s, 0, sizeof(struct t_ipt_account_stats_short) * table->count);
 183   } else {
 184     table->stats.l = vmalloc(sizeof(struct t_ipt_account_stats_long) * table->count);
 185     if (!table->stats.l) {
 186       printk(KERN_ERR "ipt_account [ipt_account_table_init]: table->stats.l = vmalloc(sizeof(struct t_ipt_account_stats_long) * table->count) failed.\n");
 187       goto cleanup_table;
 188     }
 189     memset(table->stats.l, 0, sizeof(struct t_ipt_account_stats_long) * table->count);
 190   }
 191
 192   /*
 193    * Reset locks.
 194    */
 195   table->stats_lock = RW_LOCK_UNLOCKED;
 196
 197   /*
 198    * Create /proc/ipt_account/name entry.
 199    */
 200   table->pde = create_proc_entry(table->name, S_IWUSR | S_IRUSR, ipt_account_procdir);
 201   if (!table->pde) {
 202     goto cleanup_stats;
 203   }
 204   table->pde->proc_fops = &ipt_account_proc_fops;
 205   table->pde->data = table;
 206
 207   /*
 208    * Insert table into list.
 209    */
 210   write_lock_bh(&ipt_account_lock);
 211   list_add(&table->list, &ipt_account_tables);
 212   write_unlock_bh(&ipt_account_lock);
 213
 214   return table;
 215
 216   /*
 217    * If something goes wrong we end here.
 218    */
 219 cleanup_stats:
 220   if (table->shortlisting)
 221     vfree(table->stats.s);
 222   else
 223     vfree(table->stats.l);
 224
 225 cleanup_table:
 226   vfree(table);
 227 cleanup_none:
 228   return NULL;
 229
 230 }
 231
 232 /*
 233  * Function destroys table. Table *must* be already unlinked.
 234  */
 235 static void
 236 ipt_account_table_destroy(struct t_ipt_account_table *table)
 237 {
 238 #ifdef DEBUG_IPT_ACCOUNT
 239   if (debug) printk(KERN_DEBUG "ipt_account [ipt_account_table_destory]: name = %s\n", table->name);
 240 #endif
 241   remove_proc_entry(table->pde->name, table->pde->parent);
 242   if (table->shortlisting)
 243     vfree(table->stats.s);
 244   else
 245     vfree(table->stats.l);
 246   vfree(table);
 247 }
 248
 249 /*
 250  * Function increments use counter for table.
 251  */
 252 static inline void
 253 ipt_account_table_get(struct t_ipt_account_table *table)
 254 {
 255 #ifdef DEBUG_IPT_ACCOUNT
 256   if (debug) printk(KERN_DEBUG "ipt_account [ipt_account_table_get]: name = %s\n", table->name);
 257 #endif
 258   atomic_inc(&table->use);
 259 }
 260
 261 /*
 262  * Function decrements use counter for table. If use counter drops to zero,
 263  * table is removed from linked list and destroyed.
 264  */
 265 static inline void
 266 ipt_account_table_put(struct t_ipt_account_table *table)
 267 {
 268 #ifdef DEBUG_IPT_ACCOUNT
 269   if (debug) printk(KERN_DEBUG "ipt_account [ipt_account_table_put]: name = %s\n", table->name);
 270 #endif
 271   if (atomic_dec_and_test(&table->use)) {
 272     write_lock_bh(&ipt_account_lock);
 273     list_del(&table->list);
 274     write_unlock_bh(&ipt_account_lock);
 275     ipt_account_table_destroy(table);
 276   }
 277 }
 278
 279 /*
 280  * Helper function, which returns a structure pointer to a table with
 281  * specified name.
 282  */
 283 static struct t_ipt_account_table *
 284 __ipt_account_table_find(char *name)
 285 {
 286   struct list_head *pos;
 287   list_for_each(pos, &ipt_account_tables) {
 288     struct t_ipt_account_table *table = list_entry(pos,
 289         struct t_ipt_account_table, list);
 290     if (!strncmp(table->name, name, IPT_ACCOUNT_NAME_LEN))
 291       return table;
 292   }
 293   return NULL;
 294 }
 295
 296 /*
 297  * Function, which returns a structure pointer to a table with
 298  * specified name. When such table is found its use coutner
 299  * is incremented.
 300  */
 301 static inline struct t_ipt_account_table *
 302 ipt_account_table_find_get(char *name)
 303 {
 304   struct t_ipt_account_table *table;
 305
 306 #ifdef DEBUG_IPT_ACCOUNT
 307   if (debug) printk(KERN_DEBUG "ipt_account [ipt_account_table_find_get]: name = %s\n", name);
 308 #endif
 309   read_lock_bh(&ipt_account_lock);
 310   table = __ipt_account_table_find(name);
 311   if (!table) {
 312     read_unlock_bh(&ipt_account_lock);
 313     return NULL;
 314   }
 315   atomic_inc(&table->use);
 316   read_unlock_bh(&ipt_account_lock);
 317   return table;
 318 }
 319
 320 /*
 321  * Helper function, with updates statistics for specified IP. It's only
 322  * used for tables created without --ashort switch.
 323  */
 324 static inline void
 325 __account_long(struct t_ipt_account_stat_long *stat, const struct sk_buff *skb)
 326 {
 327   stat->b_all += skb->len;
 328   stat->p_all++;
 329
 330 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22)
 331   switch (ip_hdr(skb)->protocol) {
 332 #else
 333   switch (skb->nh.iph->protocol) {
 334 #endif
 335     case IPPROTO_TCP:
 336       stat->b_tcp += skb->len;
 337       stat->p_tcp++;
 338       break;
 339     case IPPROTO_UDP:
 340       stat->b_udp += skb->len;
 341       stat->p_udp++;
 342       break;
 343     case IPPROTO_ICMP:
 344       stat->b_icmp += skb->len;
 345       stat->p_icmp++;
 346       break;
 347     default:
 348       stat->b_other += skb->len;
 349       stat->p_other++;
 350   }
 351 }
 352
 353 /*
 354  * Same as above, but used for tables created with --ashort switch.
 355  */
 356 static inline void
 357 __account_short(struct t_ipt_account_stat_short *stat, const struct sk_buff *skb)
 358 {
 359   stat->b_all += skb->len;
 360   stat->p_all++;
 361 }
 362
 363 /*
 364  * Match function. Here we do accounting stuff.
 365  */
 366 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23)
 367 static bool
 368 #else
 369 static int
 370 #endif
 371 match(const struct sk_buff *skb,
 372 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,35)
 373     struct xt_action_param *par
 374 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,29)
 375     const struct xt_match_param *par
 376 #else
 377     const struct net_device *in,
 378     const struct net_device *out,
 379 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,17)
 380     const struct xt_match *match,
 381 #endif
 382     const void *matchinfo,
 383     int offset,
 384     unsigned int protoff,
 385 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23)
 386     bool *hotdrop
 387 #else
 388     int *hotdrop
 389 #endif
 390 #endif
 391 )
 392 {
 393 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,29)
 394   struct t_ipt_account_info *info = (struct t_ipt_account_info *)(par->matchinfo);
 395 #else
 396   struct t_ipt_account_info *info = (struct t_ipt_account_info *)matchinfo;
 397 #endif
 398   struct t_ipt_account_table *table = info->table;
 399   u_int32_t address;
 400   /* Get current time. */
 401   struct timespec now = CURRENT_TIME_SEC;
 402   /* Default we assume no match. */
 403 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23)
 404   bool ret = false;
 405 #else
 406   int ret = 0;
 407 #endif
 408
 409 #ifdef DEBUG_IPT_ACCOUNT
 410   if (debug) printk(KERN_DEBUG "ipt_account [match]: name = %s\n", table->name);
 411 #endif
 412   /* Check whether traffic from source ip address ... */
 413 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22)
 414   address = ntohl(ip_hdr(skb)->saddr);
 415 #else
 416   address = ntohl(skb->nh.iph->saddr);
 417 #endif
 418   /* ... is being accounted by this table. */
 419   if (address && ((u_int32_t)(address & table->netmask) == (u_int32_t)table->network)) {
 420     write_lock_bh(&table->stats_lock);
 421     /* Yes, account this packet. */
 422 #ifdef DEBUG_IPT_ACCOUNT
 423 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22)
 424     if (debug) printk(KERN_DEBUG "ipt_account: [match]: accounting packet src = %u.%u.%u.%u, proto = %u.\n", HIPQUAD(address), ip_hdr(skb)->protocol);
 425 #else
 426     if (debug) printk(KERN_DEBUG "ipt_account: [match]: accounting packet src = %u.%u.%u.%u, proto = %u.\n", HIPQUAD(address), skb->nh.iph->protocol);
 427 #endif
 428 #endif
 429     /* Update counters this host. */
 430     if (!table->shortlisting) {
 431       __account_long(&table->stats.l[address - table->network].src, skb);
 432       if (table->timesrc)
 433         table->stats.l[address - table->network].time = now;
 434       /* Update also counters for all hosts in this table (network address) */
 435       if (table->count > 1) {
 436         __account_long(&table->stats.l[0].src, skb);
 437         table->stats.l[0].time = now;
 438       }
 439     } else {
 440       __account_short(&table->stats.s[address - table->network].src, skb);
 441       if (table->timedst)
 442         table->stats.s[address - table->network].time = now;
 443       if (table->count > 1) {
 444         __account_short(&table->stats.s[0].src, skb);
 445         table->stats.s[0].time = now;
 446       }
 447     }
 448     write_unlock_bh(&table->stats_lock);
 449     /* Yes, it's a match. */
 450 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23)
 451     ret = true;
 452 #else
 453     ret = 1;
 454 #endif
 455
 456   }
 457
 458   /* Do the same thing with destination ip address. */
 459 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22)
 460   address = ntohl(ip_hdr(skb)->daddr);
 461 #else
 462   address = ntohl(skb->nh.iph->daddr);
 463 #endif
 464   if (address && ((u_int32_t)(address & table->netmask) == (u_int32_t)table->network)) {
 465     write_lock_bh(&table->stats_lock);
 466 #ifdef DEBUG_IPT_ACCOUNT
 467 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22)
 468     if (debug) printk(KERN_DEBUG "ipt_account: [match]: accounting packet dst = %u.%u.%u.%u, proto = %u.\n", HIPQUAD(address), ip_hdr(skb)->protocol);
 469 #else
 470     if (debug) printk(KERN_DEBUG "ipt_account: [match]: accounting packet dst = %u.%u.%u.%u, proto = %u.\n", HIPQUAD(address), skb->nh.iph->protocol);
 471 #endif
 472 #endif
 473     if (!table->shortlisting) {
 474       __account_long(&table->stats.l[address - table->network].dst, skb);
 475       table->stats.l[address - table->network].time = now;
 476       if (table->count > 1) {
 477         __account_long(&table->stats.l[0].dst, skb);
 478         table->stats.l[0].time = now;
 479       }
 480     } else {
 481       __account_short(&table->stats.s[address - table->network].dst, skb);
 482       table->stats.s[address - table->network].time = now;
 483       if (table->count > 1) {
 484         __account_short(&table->stats.s[0].dst, skb);
 485         table->stats.s[0].time = now;
 486       }
 487     }
 488     write_unlock_bh(&table->stats_lock);
 489 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23)
 490     ret = true;
 491 #else
 492     ret = 1;
 493 #endif
 494   }
 495
 496   return ret;
 497 }
 498
 499 /*
 500  * Checkentry function.
 501  */
 502 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,35)
 503 static int
 504 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23)
 505 static bool
 506 #else
 507 static int
 508 #endif
 509 checkentry(
 510 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,29)
 511     const struct xt_mtchk_param *par
 512 #else
 513     const char *tablename,
 514 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,16)
 515      const void *ip,
 516 #else
 517      const struct ipt_entry *ip,
 518 #endif
 519 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,17)
 520      const struct xt_match *match,
 521 #endif
 522      void *matchinfo,
 523 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,19)
 524      unsigned int matchsize,
 525 #endif
 526      unsigned int hook_mask
 527 #endif
 528 )
 529 {
 530 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,29)
 531   struct t_ipt_account_info *info = (struct t_ipt_account_info*)(par->matchinfo);
 532 #else
 533   struct t_ipt_account_info *info = matchinfo;
 534 #endif
 535   struct t_ipt_account_table *table;
 536
 537 #ifdef DEBUG_IPT_ACCOUNT
 538   if (debug) printk(KERN_DEBUG "ipt_account [checkentry]: name = %s\n", info->name);
 539 #endif
 540 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,17)
 541   if (matchsize != IPT_ALIGN(sizeof(struct t_ipt_account_info))) {
 542 #ifdef DEBUG_IPT_ACCOUNT
 543     if (debug) printk(KERN_DEBUG "ipt_account [checkentry]: matchsize %u != %u\n", matchsize, IPT_ALIGN(sizeof(struct t_ipt_account_info)));
 544 #endif
 545 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,35)
 546     return -EINVAL;
 547 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23)
 548     return false;
 549 #else
 550     return 0;
 551 #endif
 552   }
 553 #endif
 554
 555   /*
 556    * Sanity checks.
 557    */
 558   if (info->netmask < ((~0L << (32 - netmask)) & 0xffffffff)) {
 559     printk(KERN_ERR "ipt_account[checkentry]: too big netmask (increase module 'netmask' parameter).\n");
 560 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,35)
 561     return -EINVAL;
 562 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23)
 563     return false;
 564 #else
 565     return 0;
 566 #endif
 567   }
 568   if ((info->network & info->netmask) != info->network) {
 569     printk(KERN_ERR "ipt_account[checkentry]: wrong network/netmask.\n");
 570 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,35)
 571     return -EINVAL;
 572 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23)
 573     return false;
 574 #else
 575     return 0;
 576 #endif
 577   }
 578   if (info->name[0] == '\0') {
 579     printk(KERN_ERR "ipt_account[checkentry]: wrong table name.\n");
 580 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,35)
 581     return -EINVAL;
 582 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23)
 583     return false;
 584 #else
 585     return 0;
 586 #endif
 587   }
 588
 589   /*
 590    * We got new rule. Try to find table with the same name as given in info structure.
 591    * Mutex magic based on xt_hashlimit.c.
 592    */
 593 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,28)
 594   mutex_lock(&ipt_account_mutex);
 595 #else
 596   down(&ipt_account_mutex);
 597 #endif
 598   table = ipt_account_table_find_get(info->name);
 599   if (table) {
 600     if (info->table != NULL) {
 601       if (info->table != table) {
 602         printk(KERN_ERR "ipt_account[checkentry]: reloaded rule has invalid table pointer.\n");
 603 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,28)
 604         mutex_unlock(&ipt_account_mutex);
 605 #else
 606         up(&ipt_account_mutex);
 607 #endif
 608 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,35)
 609         return -EINVAL;
 610 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23)
 611         return false;
 612 #else
 613         return 1;
 614 #endif
 615       }
 616 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,28)
 617       mutex_unlock(&ipt_account_mutex);
 618 #else
 619       up(&ipt_account_mutex);
 620 #endif
 621 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,35)
 622       return 0;
 623 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23)
 624       return true;
 625 #else
 626       return 1;
 627 #endif
 628     } else {
 629 #ifdef DEBUG_IPT_ACCOUNT
 630       if (debug) printk(KERN_DEBUG "ipt_account [checkentry]: table found, checking.\n");
 631 #endif
 632       /*
 633        * Table exists, but whether rule network/netmask/shortlisting matches
 634        * table network/netmask/shortlisting. Failure on missmatch.
 635        */
 636       if (table->network != info->network || table->netmask != info->netmask || table->shortlisting != info->shortlisting) {
 637         printk(KERN_ERR "ipt_account [checkentry]: table found, rule network/netmask/shortlisting not match table network/netmask/shortlisting.\n");
 638         /*
 639          * Remember to release table usage counter.
 640          */
 641         ipt_account_table_put(table);
 642 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,28)
 643         mutex_unlock(&ipt_account_mutex);
 644 #else
 645         up(&ipt_account_mutex);
 646 #endif
 647 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,35)
 648         return -EINVAL;
 649 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23)
 650         return false;
 651 #else
 652         return 0;
 653 #endif
 654       }
 655 #ifdef DEBUG_IPT_ACCOUNT
 656       if (debug) printk(KERN_DEBUG "ipt_account [checkentry]: table found, reusing.\n");
 657 #endif
 658       /*
 659        * Link rule with table.
 660        */
 661       info->table = table;
 662     }
 663   } else {
 664 #ifdef DEBUG_IPT_ACCOUNT
 665     if (debug) printk(KERN_DEBUG "ipt_account [checkentry]: table not found, creating new one.\n");
 666 #endif
 667     /*
 668      * Table not exist, create new one.
 669      */
 670     info->table = table = ipt_account_table_init(info);
 671     if (!table) {
 672 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,28)
 673       mutex_unlock(&ipt_account_mutex);
 674 #else
 675       up(&ipt_account_mutex);
 676 #endif
 677 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,35)
 678       return -EINVAL;
 679 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23)
 680       return false;
 681 #else
 682       return 0;
 683 #endif
 684     }
 685   }
 686 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,28)
 687   mutex_unlock(&ipt_account_mutex);
 688 #else
 689   up(&ipt_account_mutex);
 690 #endif
 691 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23)
 692   return true;
 693 #else
 694   return 1;
 695 #endif
 696 }
 697
 698 /*
 699  * Destroy function.
 700  */
 701 static void
 702 destroy(
 703 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,29)
 704     const struct xt_mtdtor_param *par
 705 #else
 706 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,17)
 707     const struct xt_match *match,
 708 #endif
 709 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,19)
 710     void *matchinfo
 711 #else
 712     void *matchinfo,
 713     unsigned int matchsize
 714 #endif
 715 #endif
 716 )
 717 {
 718 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,29)
 719   struct t_ipt_account_info *info = (struct t_ipt_account_info*)(par->matchinfo);
 720 #else
 721   struct t_ipt_account_info *info = matchinfo;
 722 #endif
 723
 724 #ifdef DEBUG_IPT_ACCOUNT
 725   if (debug) printk(KERN_DEBUG "ipt_account [destroy]: name = %s\n", info->name);
 726 #endif
 727 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,17)
 728   if (matchsize != IPT_ALIGN(sizeof(struct t_ipt_account_info))) {
 729 #ifdef DEBUG_IPT_ACCOUNT
 730     if (debug) printk(KERN_DEBUG "ipt_account [checkentry]: matchsize %u != %u\n", matchsize, IPT_ALIGN(sizeof(struct t_ipt_account_info)));
 731 #endif
 732     return;
 733   }
 734 #endif
 735
 736   /*
 737    * Release table, by decreasing its usage counter. When
 738    * counter hits zero, memory used by table structure is
 739    * released and table is removed from list.
 740    */
 741   ipt_account_table_put(info->table);
 742   return;
 743 }
 744
 745 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,21)
 746 static struct xt_match account_match = {
 747 #else
 748 static struct ipt_match account_match = {
 749 #endif
 750   .name = "account",
 751 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,28)
 752   .family = NFPROTO_IPV4,
 753 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,21)
 754   .family = AF_INET,
 755 #endif
 756   .match = &match,
 757   .checkentry = &checkentry,
 758 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,17)
 759   .matchsize = sizeof(struct t_ipt_account_info),
 760 #endif
 761   .destroy = &destroy,
 762   .me = THIS_MODULE
 763 };
 764
 765 /*
 766  * Below functions (ipt_account_seq_start, ipt_account_seq_next,
 767  * ipt_account_seq_stop, ipt_account_seq_show, ipt_account_proc_write)
 768  * are used to implement proc stuff.
 769  */
 770 static void *ipt_account_seq_start(struct seq_file *sf, loff_t *pos)
 771 {
 772   struct proc_dir_entry *pde = sf->private;
 773   struct t_ipt_account_table *table = pde->data;
 774   unsigned int *i;
 775
 776   if (table->resetonread) {
 777     /* When we reset entries after read we must have exclusive lock. */
 778     write_lock_bh(&table->stats_lock);
 779   } else {
 780     read_lock_bh(&table->stats_lock);
 781   }
 782   if (*pos >= table->count)
 783     return NULL;
 784   i = kmalloc(sizeof(unsigned int), GFP_ATOMIC);
 785   if (!i)
 786     return ERR_PTR(-ENOMEM);
 787   *i = *pos;
 788   return i;
 789 }
 790
 791 static void *ipt_account_seq_next(struct seq_file *sf, void *v, loff_t *pos)
 792 {
 793   struct proc_dir_entry *pde = sf->private;
 794   struct t_ipt_account_table *table = pde->data;
 795   unsigned int *i = (unsigned int *)v;
 796
 797   *pos = ++(*i);
 798   if (*i >= table->count) {
 799     kfree(v);
 800     return NULL;
 801   }
 802   return i;
 803 }
 804
 805 static void ipt_account_seq_stop(struct seq_file *sf, void *v)
 806 {
 807   struct proc_dir_entry *pde = sf->private;
 808   struct t_ipt_account_table *table = pde->data;
 809   kfree(v);
 810   if (table->resetonread) {
 811     write_unlock_bh(&table->stats_lock);
 812   } else {
 813     read_unlock_bh(&table->stats_lock);
 814   }
 815 }
 816
 817 static int ipt_account_seq_show(struct seq_file *sf, void *v)
 818 {
 819   struct proc_dir_entry *pde = sf->private;
 820   struct t_ipt_account_table *table = pde->data;
 821   unsigned int *i = (unsigned int *)v;
 822
 823   struct timespec now = CURRENT_TIME_SEC;
 824
 825   u_int32_t address = table->network + *i;
 826
 827   if (!table->shortlisting) {
 828     struct t_ipt_account_stats_long *l = &table->stats.l[*i];
 829     /* Don't list rows not matching show requirements. */
 830     if (
 831         ((table->show == SHOW_SRC) && (l->src.p_all == 0)) ||
 832         ((table->show == SHOW_DST) && (l->dst.p_all == 0)) ||
 833         ((table->show == SHOW_SRC_OR_DST) && ((l->src.p_all == 0) && (l->dst.p_all == 0))) ||
 834         ((table->show == SHOW_SRC_AND_DST) && ((l->src.p_all == 0) || (l->dst.p_all == 0)))
 835        ) {
 836       return 0;
 837     }
 838     seq_printf(sf,
 839         "ip = %u.%u.%u.%u bytes_src = %llu %llu %llu %llu %llu packets_src = %llu %llu %llu %llu %llu bytes_dst = %llu %llu %llu %llu %llu packets_dst = %llu %llu %llu %llu %llu time = %lu\n",
 840         HIPQUAD(address),
 841         l->src.b_all,
 842         l->src.b_tcp,
 843         l->src.b_udp,
 844         l->src.b_icmp,
 845         l->src.b_other,
 846         l->src.p_all,
 847         l->src.p_tcp,
 848         l->src.p_udp,
 849         l->src.p_icmp,
 850         l->src.p_other,
 851         l->dst.b_all,
 852         l->dst.b_tcp,
 853         l->dst.b_udp,
 854         l->dst.b_icmp,
 855         l->dst.b_other,
 856         l->dst.p_all,
 857         l->dst.p_tcp,
 858         l->dst.p_udp,
 859         l->dst.p_icmp,
 860         l->dst.p_other,
 861         now.tv_sec - l->time.tv_sec
 862       );
 863     if (table->resetonread)
 864       memset(l, 0, sizeof(struct t_ipt_account_stats_long));
 865
 866   } else {
 867     struct t_ipt_account_stats_short *s = &table->stats.s[*i];
 868     if (
 869         ((table->show == SHOW_SRC) && (s->src.p_all == 0)) ||
 870         ((table->show == SHOW_DST) && (s->dst.p_all == 0)) ||
 871         ((table->show == SHOW_SRC_OR_DST) && ((s->src.p_all == 0) && (s->dst.p_all == 0))) ||
 872         ((table->show == SHOW_SRC_AND_DST) && ((s->src.p_all == 0) || (s->dst.p_all == 0)))
 873        ) {
 874       return 0;
 875     }
 876     seq_printf(sf,
 877         "ip = %u.%u.%u.%u bytes_src = %llu packets_src = %llu bytes_dst = %llu packets_dst = %llu time = %lu\n",
 878         HIPQUAD(address),
 879         s->src.b_all,
 880         s->src.p_all,
 881         s->dst.b_all,
 882         s->dst.p_all,
 883         now.tv_sec - s->time.tv_sec
 884       );
 885     if (table->resetonread)
 886       memset(s, 0, sizeof(struct t_ipt_account_stats_short));
 887   }
 888
 889   return 0;
 890 }
 891
 892 static struct seq_operations ipt_account_seq_ops = {
 893   .start = ipt_account_seq_start,
 894   .next = ipt_account_seq_next,
 895   .stop = ipt_account_seq_stop,
 896   .show = ipt_account_seq_show
 897 };
 898
 899 static ssize_t ipt_account_proc_write(struct file *file, const char __user *input, size_t size, loff_t *ofs)
 900 {
 901   char buffer[1024];
 902   struct proc_dir_entry *pde = PDE(file->f_dentry->d_inode);
 903   struct t_ipt_account_table *table = pde->data;
 904
 905   u_int32_t o[4], ip;
 906   struct t_ipt_account_stats_long l;
 907   struct t_ipt_account_stats_short s;
 908
 909 #ifdef DEBUG_IPT_ACCOUNT
 910   if (debug) printk(KERN_DEBUG "ipt_account [ipt_account_proc_write]: name = %s.\n", table->name);
 911 #endif
 912   if (copy_from_user(buffer, input, 1024))
 913     return -EFAULT;
 914   buffer[1023] = '\0';
 915
 916   if (!strncmp(buffer, "reset\n", 6)) {
 917     /*
 918      * User requested to clear all table. Ignorant, does
 919      * he known how match time it took us to fill it? ;-)
 920      */
 921     write_lock_bh(&table->stats_lock);
 922     if (table->shortlisting)
 923       memset(table->stats.s, 0, sizeof(struct t_ipt_account_stats_short) * table->count);
 924     else
 925       memset(table->stats.l, 0, sizeof(struct t_ipt_account_stats_long) * table->count);
 926     write_unlock_bh(&table->stats_lock);
 927   } else if (!strncmp(buffer, "reset-on-read=yes\n", 18)) {
 928     /*
 929      * We must be sure that ipt_account_seq_* is not running now. This option
 930      * changes lock type which is taken in ipt_account_seq_{start|stop}. When
 931      * we change this option without this lock, and ipt_account_seq_start is
 932      * already run (but not ipt_account_seq_stop) there is possibility that
 933      * we execute wrong "unlock" function.
 934      */
 935     write_lock_bh(&table->stats_lock);
 936     table->resetonread = 1;
 937     write_unlock_bh(&table->stats_lock);
 938   } else if (!strncmp(buffer, "reset-on-read=no\n", 17)) {
 939     write_lock_bh(&table->stats_lock);
 940     table->resetonread = 0;
 941     write_unlock_bh(&table->stats_lock);
 942   } else if (!strncmp(buffer, "reset-on-read\n", 14)) {
 943     write_lock_bh(&table->stats_lock);
 944     table->resetonread = 1;
 945     write_unlock_bh(&table->stats_lock);
 946   } else if (!strncmp(buffer, "show=any\n", 9)) {
 947     /*
 948      * Here we should lock but we don't have to. So we don't lock. We only get
 949      * wrong results on already run ipt_account_seq_show, but we won't crush
 950      * the system.
 951      */
 952     table->show = SHOW_ANY;
 953   } else if (!strncmp(buffer, "show=src\n", 9)) {
 954     table->show = SHOW_SRC;
 955   } else if (!strncmp(buffer, "show=dst\n", 9)) {
 956     table->show = SHOW_DST;
 957   } else if (!strncmp(buffer, "show=src-or-dst\n", 16) || !strncmp(buffer, "show=dst-or-src\n", 16)) {
 958     table->show = SHOW_SRC_OR_DST;
 959   } else if (!strncmp(buffer, "show=src-and-dst\n", 17) || !strncmp(buffer, "show=dst-and-src\n", 17)) {
 960     table->show = SHOW_SRC_AND_DST;
 961   } else if (!strncmp(buffer, "time=any\n", 9)) {
 962     table->timesrc = table->timedst = 1;
 963   } else if (!strncmp(buffer, "time=src\n", 9)) {
 964     table->timesrc = 1;
 965     table->timedst = 0;
 966   } else if (!strncmp(buffer, "time=dst\n", 9)) {
 967     table->timesrc = 0;
 968     table->timedst = 1;
 969   } else if (!table->shortlisting && sscanf(buffer, "ip = %u.%u.%u.%u bytes_src = %llu %llu %llu %llu %llu packets_src = %llu %llu %llu %llu %llu bytes_dst = %llu %llu %llu %llu %llu packets_dst = %llu %llu %llu %llu %llu time = %lu",
 970         &o[0], &o[1], &o[2], &o[3],
 971         &l.src.b_all, &l.src.b_tcp, &l.src.b_udp, &l.src.b_icmp, &l.src.b_other,
 972         &l.src.p_all, &l.src.p_tcp, &l.src.p_udp, &l.src.p_icmp, &l.src.p_other,
 973         &l.dst.b_all, &l.dst.b_tcp, &l.dst.b_udp, &l.dst.b_icmp, &l.dst.b_other,
 974         &l.dst.p_all, &l.dst.p_tcp, &l.dst.p_udp, &l.dst.p_icmp, &l.dst.p_other,
 975         &l.time.tv_sec) == 25 ) {
 976     /*
 977      * We got line formated like long listing row. We have to
 978      * check, if IP is accounted by table. If so, we
 979      * simply replace row with user's one.
 980      */
 981     ip = o[0] << 24 | o[1] << 16 | o[2] << 8 | o[3];
 982     if ((u_int32_t)(ip & table->netmask) == (u_int32_t)table->network) {
 983       /*
 984        * Ignore user input time. Set current time.
 985        */
 986       l.time = CURRENT_TIME_SEC;
 987       write_lock_bh(&table->stats_lock);
 988       table->stats.l[ip - table->network] = l;
 989       write_unlock_bh(&table->stats_lock);
 990     }
 991   } else if (table->shortlisting && sscanf(buffer, "ip = %u.%u.%u.%u bytes_src = %llu packets_src = %llu bytes_dst = %llu packets_dst = %llu time = %lu\n",
 992         &o[0], &o[1], &o[2], &o[3],
 993         &s.src.b_all,
 994         &s.src.p_all,
 995         &s.dst.b_all,
 996         &s.dst.p_all,
 997         &s.time.tv_sec) == 9) {
 998     /*
 999      * We got line formated like short listing row. Do the
1000      * same action like above.
1001      */
1002     ip = o[0] << 24 | o[1] << 16 | o[2] << 8 | o[3];
1003     if ((u_int32_t)(ip & table->netmask) == (u_int32_t)table->network) {
1004       s.time = CURRENT_TIME_SEC;
1005       write_lock_bh(&table->stats_lock);
1006       table->stats.s[ip - table->network] = s;
1007       write_unlock_bh(&table->stats_lock);
1008     }
1009   } else {
1010     /*
1011      * We don't understand what user have just wrote.
1012      */
1013     return -EIO;
1014   }
1015
1016   return size;
1017 }
1018
1019 static int ipt_account_proc_open(struct inode *inode, struct file *file)
1020 {
1021   int ret = seq_open(file, &ipt_account_seq_ops);
1022   if (!ret) {
1023     struct seq_file *sf = file->private_data;
1024     struct proc_dir_entry *pde = PDE(inode);
1025     struct t_ipt_account_table *table = pde->data;
1026
1027     sf->private = pde;
1028
1029     ipt_account_table_get(table);
1030   }
1031   return ret;
1032 }
1033
1034 static int ipt_account_proc_release(struct inode *inode, struct file *file)
1035 {
1036   struct proc_dir_entry *pde = PDE(inode);
1037   struct t_ipt_account_table *table = pde->data;
1038   int ret;
1039
1040   ret = seq_release(inode, file);
1041
1042   if (!ret)
1043     ipt_account_table_put(table);
1044
1045   return ret;
1046 }
1047
1048 static struct file_operations ipt_account_proc_fops = {
1049   .owner = THIS_MODULE,
1050   .open = ipt_account_proc_open,
1051   .read = seq_read,
1052   .write = ipt_account_proc_write,
1053   .llseek = seq_lseek,
1054   .release = ipt_account_proc_release
1055 };
1056
1057 /*
1058  * Module init function.
1059  */
1060 static int __init init(void)
1061 {
1062   int ret = 0;
1063
1064   printk(KERN_INFO "ipt_account %s : Piotr Gasidlo <quaker@barbara.eu.org>, http://www.barbara.eu.org/~quaker/ipt_account/\n", IPT_ACCOUNT_VERSION);
1065
1066   /* Check module parameters. */
1067   if (netmask > 32 || netmask < 0) {
1068     printk(KERN_ERR "ipt_account[__init]: Wrong netmask given as parameter (%i). Valid is 32 to 0.\n", netmask);
1069     ret = -EINVAL;
1070     goto cleanup_none;
1071   }
1072
1073   /* Register match. */
1074 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,21)
1075   if (xt_register_match(&account_match)) {
1076 #else
1077   if (ipt_register_match(&account_match)) {
1078 #endif
1079     ret = -EINVAL;
1080     goto cleanup_none;
1081   }
1082
1083   /* Create /proc/net/ipt_account/ entry. */
1084 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
1085   ipt_account_procdir = proc_mkdir("ipt_account", init_net.proc_net);
1086 #else
1087   ipt_account_procdir = proc_mkdir("ipt_account", proc_net);
1088 #endif
1089   if (!ipt_account_procdir) {
1090 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
1091     printk(KERN_ERR "ipt_account [__init]: ipt_account_procdir = proc_mkdir(\"ipt_account\", init_proc.proc_net) failed.\n");
1092 #else
1093     printk(KERN_ERR "ipt_account [__init]: ipt_account_procdir = proc_mkdir(\"ipt_account\", proc_net) failed.\n");
1094 #endif
1095     ret = -ENOMEM;
1096     goto cleanup_match;
1097   }
1098
1099   return ret;
1100
1101   /* If something goes wrong we end here. */
1102 cleanup_match:
1103 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,21)
1104   xt_unregister_match(&account_match);
1105 #else
1106   ipt_unregister_match(&account_match);
1107 #endif
1108 cleanup_none:
1109   return ret;
1110 }
1111
1112 /*
1113  * Module exit function.
1114  */
1115 static void __exit fini(void)
1116 {
1117   /* Remove /proc/net/ipt_account/ */
1118   remove_proc_entry(ipt_account_procdir->name, ipt_account_procdir->parent);
1119 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,21)
1120   xt_unregister_match(&account_match);
1121 #else
1122   ipt_unregister_match(&account_match);
1123 #endif
1124 }
1125
1126 module_init(init);
1127 module_exit(fini);
1128