developer.intra2net.com Git - ipt_ACCOUNT/blob - linux/net/ipv4/netfilter/ipt_ACCOUNT.c

   1 /*
   2  * This is a module which is used for counting packets.
   3  */
   4 #include <linux/module.h>
   5 #include <linux/skbuff.h>
   6 #include <linux/ip.h>
   7 #include <linux/spinlock.h>
   8 #include <net/icmp.h>
   9 #include <net/udp.h>
  10 #include <net/tcp.h>
  11 #include <linux/netfilter_ipv4/ip_tables.h>
  12
  13 struct in_device;
  14 #include <net/route.h>
  15 #include <linux/netfilter_ipv4/ipt_ACCOUNT.h>
  16
  17 #if 0
  18 #define DEBUGP printk
  19 #else
  20 #define DEBUGP(format, args...)
  21 #endif
  22
  23 struct ipt_account_table *ipt_account_tables = NULL;
  24 struct ipt_account_handle *ipt_account_handles = NULL;
  25 void *ipt_account_tmpbuf = NULL;
  26
  27 // Spinlock used for manipulating the current accounting tables/data
  28 static spinlock_t ipt_account_lock = SPIN_LOCK_UNLOCKED;
  29 // Spinlock used for manipulating userspace handles/snapshot data
  30 static spinlock_t ipt_account_userspace_lock = SPIN_LOCK_UNLOCKED;
  31
  32
  33 /* Recursive free of all data structures */
  34 void ipt_account_data_free(void *data, unsigned char depth)
  35 {
  36     // Empty data set
  37     if (!data)
  38         return;
  39
  40     // Free for 8 bit network
  41     if (depth == 0)
  42     {
  43         free_page((unsigned long)data);
  44         data = NULL;
  45         return;
  46     }
  47
  48     // Free for 16 bit network
  49     if (depth == 1)
  50     {
  51         struct ipt_account_mask_16 *mask_16 = (struct ipt_account_mask_16 *)data;
  52         unsigned int b;
  53         for (b=0; b <= 255; b++)
  54         {
  55             if (mask_16->mask_24[b] != 0)
  56             {
  57                 free_page((unsigned long)mask_16->mask_24[b]);
  58                 mask_16->mask_24[b] = NULL;
  59             }
  60         }
  61         free_page((unsigned long)data);
  62         data = NULL;
  63         return;
  64     }
  65
  66     // Free for 24 bit network
  67     if (depth == 3)
  68     {
  69         unsigned int a, b;
  70         for (a=0; a <= 255; a++)
  71         {
  72             if (((struct ipt_account_mask_8 *)data)->mask_16[a])
  73             {
  74                 struct ipt_account_mask_16 *mask_16 = (struct ipt_account_mask_16*)((struct ipt_account_mask_8 *)data)->mask_16[a];
  75                 for (b=0; b <= 255; b++)
  76                 {
  77                     if (mask_16->mask_24[b]) {
  78                         free_page((unsigned long)mask_16->mask_24[b]);
  79                         mask_16->mask_24[b] = NULL;
  80                     }
  81                 }
  82                 free_page((unsigned long)mask_16);
  83                 mask_16 = NULL;
  84             }
  85         }
  86         free_page((unsigned long)data);
  87         data = NULL;
  88         return;
  89     }
  90
  91     printk("ACCOUNT: ipt_account_data_free called with unknown depth: %d\n", depth);
  92     return;
  93 }
  94
  95 /* Look for existing table / insert new one. Return internal ID or -1 on error */
  96 int ipt_account_table_insert(char *name, unsigned int ip, unsigned int netmask)
  97 {
  98     unsigned int i;
  99
 100     DEBUGP("ACCOUNT: ipt_account_table_insert: %s, %u.%u.%u.%u/%u.%u.%u.%u\n", name, NIPQUAD(ip), NIPQUAD(netmask));
 101
 102     // Look for existing table
 103     for (i = 0; i < ACCOUNT_MAX_TABLES; i++)
 104     {
 105         if (strncmp(ipt_account_tables[i].name, name, ACCOUNT_TABLE_NAME_LEN) == 0)
 106         {
 107             DEBUGP("ACCOUNT: Found existing slot: %d - %u.%u.%u.%u/%u.%u.%u.%u\n", i,
 108                    NIPQUAD(ipt_account_tables[i].ip), NIPQUAD(ipt_account_tables[i].netmask));
 109
 110             if (ipt_account_tables[i].ip != ip || ipt_account_tables[i].netmask != netmask)
 111             {
 112                 printk("ACCOUNT: Table %s found, but IP/netmask mismatch. IP/netmask found: %u.%u.%u.%u/%u.%u.%u.%u\n",
 113                         name, NIPQUAD(ipt_account_tables[i].ip), NIPQUAD(ipt_account_tables[i].netmask));
 114                 return -1;
 115             }
 116
 117             ipt_account_tables[i].refcount++;
 118             DEBUGP("ACCOUNT: Refcount: %d\n", ipt_account_tables[i].refcount);
 119             return i;
 120         }
 121     }
 122
 123     // Insert new table
 124     for (i = 0; i < ACCOUNT_MAX_TABLES; i++)
 125     {
 126         // Found free slot
 127         if (ipt_account_tables[i].name[0] == 0)
 128         {
 129             DEBUGP("ACCOUNT: Found free slot: %d\n", i);
 130
 131             strncpy (ipt_account_tables[i].name, name, ACCOUNT_TABLE_NAME_LEN-1);
 132
 133             ipt_account_tables[i].ip = ip;
 134             ipt_account_tables[i].netmask = netmask;
 135
 136             // Calculate netsize
 137             unsigned int j, calc_mask, netsize=0;
 138             calc_mask = htonl(netmask);
 139             for (j = 31; j > 0; j--)
 140             {
 141                 if (calc_mask&(1<<j))
 142                     netsize++;
 143                 else
 144                     break;
 145             }
 146
 147             // Calculate depth from netsize
 148             if (netsize >= 24)
 149                 ipt_account_tables[i].depth = 0;
 150             else if (netsize >= 16)
 151                 ipt_account_tables[i].depth = 1;
 152             else if(netsize >= 8)
 153                 ipt_account_tables[i].depth = 2;
 154
 155             printk("ACCOUNT: calculated netsize: %u -> ipt_account_table depth %u\n", netsize, ipt_account_tables[i].depth);
 156
 157             ipt_account_tables[i].refcount++;
 158             if ((ipt_account_tables[i].data = (void *)get_zeroed_page(GFP_KERNEL)) == NULL)
 159             {
 160                 printk("ACCOUNT: out of memory for data of table: %s\n", name);
 161                 memset(&ipt_account_tables[i], 0, sizeof(struct ipt_account_table));
 162                 return -1;
 163             }
 164
 165             return i;
 166         }
 167     }
 168
 169     // No free slot found
 170     printk("ACCOUNT: No free table slot found (max: %d). Please increase ACCOUNT_MAX_TABLES.\n", ACCOUNT_MAX_TABLES);
 171     return -1;
 172 }
 173
 174 static int ipt_account_checkentry(const char *tablename,
 175     const struct ipt_entry *e,
 176     void *targinfo,
 177     unsigned int targinfosize,
 178     unsigned int hook_mask)
 179 {
 180     struct ipt_account_info *info = targinfo;
 181
 182     if (targinfosize != IPT_ALIGN(sizeof(struct ipt_account_info))) {
 183         DEBUGP("ACCOUNT: targinfosize %u != %u\n",
 184                 targinfosize, IPT_ALIGN(sizeof(struct ipt_account_info)));
 185         return 0;
 186     }
 187
 188     spin_lock_bh(&ipt_account_lock);
 189     int table_nr = ipt_account_table_insert(info->table_name, info->net_ip, info->net_mask);
 190     if (table_nr == -1)
 191     {
 192         printk("ACCOUNT: Table insert problem. Aborting\n");
 193         spin_unlock_bh(&ipt_account_lock);
 194         return 0;
 195     }
 196     // Table nr caching so we don't have to do an extra string compare for every packet
 197     info->table_nr = table_nr;
 198
 199     spin_unlock_bh(&ipt_account_lock);
 200
 201     return 1;
 202 }
 203
 204 void ipt_account_deleteentry(void *targinfo, unsigned int targinfosize)
 205 {
 206     unsigned int i;
 207     struct ipt_account_info *info = targinfo;
 208
 209     if (targinfosize != IPT_ALIGN(sizeof(struct ipt_account_info))) {
 210         DEBUGP("ACCOUNT: targinfosize %u != %u\n",
 211                 targinfosize, IPT_ALIGN(sizeof(struct ipt_account_info)));
 212     }
 213
 214     spin_lock_bh(&ipt_account_lock);
 215
 216     DEBUGP("ACCOUNT: ipt_account_deleteentry called for table: %s (#%d)\n", info->table_name, info->table_nr);
 217
 218     info->table_nr = -1;    // Set back to original state
 219
 220     // Look for table
 221     for (i = 0; i < ACCOUNT_MAX_TABLES; i++)
 222     {
 223         if (strncmp(ipt_account_tables[i].name, info->table_name, ACCOUNT_TABLE_NAME_LEN) == 0)
 224         {
 225             DEBUGP("ACCOUNT: Found table at slot: %d\n", i);
 226
 227             ipt_account_tables[i].refcount--;
 228             DEBUGP("ACCOUNT: Refcount left: %d\n", ipt_account_tables[i].refcount);
 229
 230             // Table not needed anymore?
 231             if (ipt_account_tables[i].refcount == 0)
 232             {
 233                 DEBUGP("ACCOUNT: Destroying table at slot: %d\n", i);
 234                 ipt_account_data_free(ipt_account_tables[i].data, ipt_account_tables[i].depth);
 235                 memset(&ipt_account_tables[i], 0, sizeof(struct ipt_account_table));
 236             }
 237
 238             spin_unlock_bh(&ipt_account_lock);
 239             return;
 240         }
 241     }
 242
 243     // Table not found
 244     printk("ACCOUNT: Table %s not found for destroy\n", info->table_name);
 245     spin_unlock_bh(&ipt_account_lock);
 246 }
 247
 248 void ipt_account_depth0_insert(struct ipt_account_mask_24 *mask_24, unsigned int net_ip, unsigned int netmask,
 249                                unsigned int src_ip, unsigned int dst_ip, unsigned int size, unsigned int *itemcount)
 250 {
 251     unsigned char is_src = 0, is_dst = 0;
 252
 253     DEBUGP("ACCOUNT: ipt_account_depth0_insert: %u.%u.%u.%u/%u.%u.%u.%u for net %u.%u.%u.%u/%u.%u.%u.%u, size: %u\n",
 254             NIPQUAD(src_ip), NIPQUAD(dst_ip), NIPQUAD(net_ip), NIPQUAD(netmask), size);
 255
 256     // Check if src/dst is inside our network.
 257     // Special: net_ip = 0.0.0.0/0 gets stored as src in slot 0
 258     if (!netmask)
 259         src_ip = 0;
 260     if ((net_ip&netmask) == (src_ip&netmask))
 261         is_src = 1;
 262     if ((net_ip&netmask) == (dst_ip&netmask) && netmask)
 263         is_dst = 1;
 264
 265     if (!is_src && !is_dst)
 266     {
 267         DEBUGP("ACCOUNT: Skipping packet %u.%u.%u.%u/%u.%u.%u.%u for net %u.%u.%u.%u/%u.%u.%u.%u\n",
 268                 NIPQUAD(src_ip), NIPQUAD(dst_ip), NIPQUAD(net_ip), NIPQUAD(netmask));
 269         return;
 270     }
 271
 272     // Check if this entry is new
 273     char is_src_new_ip = 0, is_dst_new_ip = 0;
 274
 275     // Calculate array positions
 276     unsigned char src_slot = (unsigned char)((src_ip&0xFF000000) >> 24);
 277     unsigned char dst_slot = (unsigned char)((dst_ip&0xFF000000) >> 24);
 278
 279     // Increase size counters
 280     if (is_src)
 281     {
 282         // Calculate network slot
 283         DEBUGP("ACCOUNT: Calculated SRC 8 bit network slot: %d\n", src_slot);
 284         if (!mask_24->ip[src_slot].src_packets && !mask_24->ip[src_slot].dst_packets)
 285             is_src_new_ip = 1;
 286
 287         mask_24->ip[src_slot].src_packets++;
 288         mask_24->ip[src_slot].src_bytes+=size;
 289     }
 290     if (is_dst)
 291     {
 292         DEBUGP("ACCOUNT: Calculated DST 8 bit network slot: %d\n", dst_slot);
 293         if (!mask_24->ip[dst_slot].src_packets && !mask_24->ip[dst_slot].dst_packets)
 294             is_dst_new_ip = 1;
 295
 296         mask_24->ip[dst_slot].dst_packets++;
 297         mask_24->ip[dst_slot].dst_bytes+=size;
 298     }
 299
 300     // Increase itemcounter
 301     DEBUGP("ACCOUNT: Itemcounter before: %d\n", *itemcount);
 302     if (src_slot == dst_slot)
 303     {
 304         if (is_src_new_ip || is_dst_new_ip) {
 305             DEBUGP("ACCOUNT: src_slot == dst_slot: %d, %d\n", is_src_new_ip, is_dst_new_ip);
 306             (*itemcount)++;
 307         }
 308     } else {
 309         if (is_src_new_ip) {
 310             DEBUGP("ACCOUNT: New src_ip: %u.%u.%u.%u\n", NIPQUAD(src_ip));
 311             (*itemcount)++;
 312         }
 313         if (is_dst_new_ip) {
 314             DEBUGP("ACCOUNT: New dst_ip: %u.%u.%u.%u\n", NIPQUAD(dst_ip));
 315             (*itemcount)++;
 316         }
 317     }
 318     DEBUGP("ACCOUNT: Itemcounter after: %d\n", *itemcount);
 319 }
 320
 321 void ipt_account_depth1_insert(struct ipt_account_mask_16 *mask_16, unsigned int net_ip, unsigned int netmask,
 322                                unsigned int src_ip, unsigned int dst_ip, unsigned int size, unsigned int *itemcount)
 323 {
 324     // Do we need to process src IP?
 325     if ((net_ip&netmask) == (src_ip&netmask))
 326     {
 327         unsigned char slot = (unsigned char)((src_ip&0x00FF0000) >> 16);
 328         DEBUGP("ACCOUNT: Calculated SRC 16 bit network slot: %d\n", slot);
 329
 330         // Do we need to create a new mask_24 bucket?
 331         if (!mask_16->mask_24[slot] && (mask_16->mask_24[slot] = (void *)get_zeroed_page(GFP_KERNEL)) == NULL)
 332         {
 333             printk("ACCOUNT: Can't process packet because out of memory!\n");
 334             return;
 335         }
 336
 337         ipt_account_depth0_insert((struct ipt_account_mask_24 *)mask_16->mask_24[slot], net_ip, netmask,
 338                                     src_ip, 0, size, itemcount);
 339     }
 340
 341     // Do we need to process dst IP?
 342     if ((net_ip&netmask) == (dst_ip&netmask))
 343     {
 344         unsigned char slot = (unsigned char)((dst_ip&0x00FF0000) >> 16);
 345         DEBUGP("ACCOUNT: Calculated DST 16 bit network slot: %d\n", slot);
 346
 347         // Do we need to create a new mask_24 bucket?
 348         if (!mask_16->mask_24[slot] && (mask_16->mask_24[slot] = (void *)get_zeroed_page(GFP_KERNEL)) == NULL)
 349         {
 350             printk("ACCOUT: Can't process packet because out of memory!\n");
 351             return;
 352         }
 353
 354         ipt_account_depth0_insert((struct ipt_account_mask_24 *)mask_16->mask_24[slot], net_ip, netmask,
 355                                     0, dst_ip, size, itemcount);
 356     }
 357 }
 358
 359 void ipt_account_depth2_insert(struct ipt_account_mask_8 *mask_8, unsigned int net_ip, unsigned int netmask,
 360                                unsigned int src_ip, unsigned int dst_ip, unsigned int size, unsigned int *itemcount)
 361 {
 362     // Do we need to process src IP?
 363     if ((net_ip&netmask) == (src_ip&netmask))
 364     {
 365         unsigned char slot = (unsigned char)((src_ip&0x0000FF00) >> 8);
 366         DEBUGP("ACCOUNT: Calculated SRC 24 bit network slot: %d\n", slot);
 367
 368         // Do we need to create a new mask_24 bucket?
 369         if (!mask_8->mask_16[slot] && (mask_8->mask_16[slot] = (void *)get_zeroed_page(GFP_KERNEL)) == NULL)
 370         {
 371             printk("ACCOUNT: Can't process packet because out of memory!\n");
 372             return;
 373         }
 374
 375         ipt_account_depth1_insert((struct ipt_account_mask_16 *)mask_8->mask_16[slot], net_ip, netmask,
 376                                     src_ip, 0, size, itemcount);
 377     }
 378
 379     // Do we need to process dst IP?
 380     if ((net_ip&netmask) == (dst_ip&netmask))
 381     {
 382         unsigned char slot = (unsigned char)((dst_ip&0x0000FF00) >> 8);
 383         DEBUGP("ACCOUNT: Calculated DST 24 bit network slot: %d\n", slot);
 384
 385         // Do we need to create a new mask_24 bucket?
 386         if (!mask_8->mask_16[slot] && (mask_8->mask_16[slot] = (void *)get_zeroed_page(GFP_KERNEL)) == NULL)
 387         {
 388             printk("ACCOUNT: Can't process packet because out of memory!\n");
 389             return;
 390         }
 391
 392         ipt_account_depth1_insert((struct ipt_account_mask_16 *)mask_8->mask_16[slot], net_ip, netmask,
 393                                     0, dst_ip, size, itemcount);
 394     }
 395 }
 396
 397 static unsigned int ipt_account_target(struct sk_buff **pskb,
 398     unsigned int hooknum,
 399     const struct net_device *in,
 400     const struct net_device *out,
 401     const void *targinfo,
 402     void *userinfo)
 403 {
 404     const struct ipt_account_info *info = (const struct ipt_account_info *)targinfo;
 405     unsigned int src_ip = (*pskb)->nh.iph->saddr;
 406     unsigned int dst_ip = (*pskb)->nh.iph->daddr;
 407     unsigned int size = ntohs((*pskb)->nh.iph->tot_len);
 408
 409     spin_lock_bh(&ipt_account_lock);
 410
 411     if (ipt_account_tables[info->table_nr].name[0] == 0)
 412     {
 413         printk("ACCOUNT: ipt_account_target: Invalid table id %u. IPs %u.%u.%u.%u/%u.%u.%u.%u\n",
 414                info->table_nr, NIPQUAD(src_ip), NIPQUAD(dst_ip));
 415         spin_unlock_bh(&ipt_account_lock);
 416         return IPT_CONTINUE;
 417     }
 418
 419     // 8 bit network or "any" network
 420     if (ipt_account_tables[info->table_nr].depth == 0)
 421     {
 422         // Count packet and check if the IP is new
 423         ipt_account_depth0_insert((struct ipt_account_mask_24 *)ipt_account_tables[info->table_nr].data,
 424                                   ipt_account_tables[info->table_nr].ip, ipt_account_tables[info->table_nr].netmask,
 425                                   src_ip, dst_ip, size, &ipt_account_tables[info->table_nr].itemcount);
 426         spin_unlock_bh(&ipt_account_lock);
 427         return IPT_CONTINUE;
 428     }
 429
 430     // 16 bit network
 431     if (ipt_account_tables[info->table_nr].depth == 1)
 432     {
 433         ipt_account_depth1_insert((struct ipt_account_mask_16 *)ipt_account_tables[info->table_nr].data,
 434                                   ipt_account_tables[info->table_nr].ip, ipt_account_tables[info->table_nr].netmask,
 435                                   src_ip, dst_ip, size, &ipt_account_tables[info->table_nr].itemcount);
 436         spin_unlock_bh(&ipt_account_lock);
 437         return IPT_CONTINUE;
 438     }
 439
 440     // 24 bit network
 441     if (ipt_account_tables[info->table_nr].depth == 2)
 442     {
 443         ipt_account_depth2_insert((struct ipt_account_mask_8 *)ipt_account_tables[info->table_nr].data,
 444                                   ipt_account_tables[info->table_nr].ip, ipt_account_tables[info->table_nr].netmask,
 445                                   src_ip, dst_ip, size, &ipt_account_tables[info->table_nr].itemcount);
 446         spin_unlock_bh(&ipt_account_lock);
 447         return IPT_CONTINUE;
 448     }
 449
 450     printk("ACCOUNT: ipt_account_target: Unable to process packet. Table id %u. IPs %u.%u.%u.%u/%u.%u.%u.%u\n",
 451             info->table_nr, NIPQUAD(src_ip), NIPQUAD(dst_ip));
 452
 453     spin_unlock_bh(&ipt_account_lock);
 454     return IPT_CONTINUE;
 455 }
 456
 457 /*
 458     Functions dealing with "handles":
 459     Handles are snapshots of a accounting state.
 460
 461     read snapshots are only for debugging the code
 462     and are very expensive concerning speed/memory
 463     compared to read_and_flush.
 464
 465     The functions aren't protected by spinlocks themselves
 466     as this is done in the ioctl part of the code.
 467 */
 468
 469 /*
 470     Find a free handle slot. Normally only one should be used,
 471     but there could be two or more applications accessing the data
 472     at the same time.
 473 */
 474 int ipt_account_handle_find_slot(void)
 475 {
 476     unsigned int i;
 477     // Insert new table
 478     for (i = 0; i < ACCOUNT_MAX_HANDLES; i++)
 479     {
 480         // Found free slot
 481         if (ipt_account_handles[i].data == NULL)
 482         {
 483             // Don't "mark" data as used as we are protected by a spinlock by the calling function.
 484             // handle_find_slot() is only a function to prevent code duplication.
 485             return i;
 486         }
 487     }
 488
 489     // No free slot found
 490     printk("ACCOUNT: No free handle slot found (max: %u). Please increase ACCOUNT_MAX_HANDLES.\n", ACCOUNT_MAX_HANDLES);
 491     return -1;
 492 }
 493
 494 int ipt_account_handle_free(unsigned int handle)
 495 {
 496     if (handle >= ACCOUNT_MAX_HANDLES)
 497     {
 498         printk("ACCOUNT: Invalid handle for ipt_account_handle_free() specified: %u\n", handle);
 499         return -EINVAL;
 500     }
 501
 502     ipt_account_data_free(ipt_account_handles[handle].data, ipt_account_handles[handle].depth);
 503     memset (&ipt_account_handles[handle], 0, sizeof (struct ipt_account_handle));
 504     return 0;
 505 }
 506
 507 /* Prepare data for read without flush. Use only for debugging!
 508    Real applications should use read&flush as it's way more efficent */
 509 int ipt_account_handle_prepare_read(char *tablename, unsigned int *count)
 510 {
 511     int handle, i, table_nr=-1;
 512
 513     for (i = 0; i < ACCOUNT_MAX_TABLES; i++)
 514         if (strncmp(ipt_account_tables[i].name, tablename, ACCOUNT_TABLE_NAME_LEN) == 0)
 515         {
 516             table_nr = i;
 517             break;
 518         }
 519
 520     if (table_nr == -1)
 521     {
 522         printk("ACCOUNT: ipt_account_handle_prepare_read(): Table %s not found\n", tablename);
 523         return -1;
 524     }
 525
 526     // Can't find a free handle slot?
 527     if ((handle = ipt_account_handle_find_slot()) == -1)
 528         return -1;
 529
 530     // Fill up handle structure
 531     ipt_account_handles[handle].ip = ipt_account_tables[table_nr].ip;
 532     ipt_account_handles[handle].depth = ipt_account_tables[table_nr].depth;
 533     ipt_account_handles[handle].itemcount = ipt_account_tables[table_nr].itemcount;
 534
 535     // allocate "root" table
 536     if ((ipt_account_handles[handle].data = (void*)get_zeroed_page(GFP_KERNEL)) == NULL)
 537     {
 538         printk("ACCOUNT: out of memory for root table in ipt_account_handle_prepare_read()\n");
 539         memset (&ipt_account_handles[handle], 0, sizeof(struct ipt_account_handle));
 540         return -1;
 541     }
 542
 543     // Recursive copy of complete data structure
 544     unsigned int depth = ipt_account_handles[handle].depth;
 545     if (depth == 0)
 546     {
 547         memcpy(ipt_account_handles[handle].data, ipt_account_tables[table_nr].data, sizeof(struct ipt_account_mask_24));
 548     } else if (depth == 1) {
 549         struct ipt_account_mask_16 *src_16 = (struct ipt_account_mask_16 *)ipt_account_tables[table_nr].data;
 550         struct ipt_account_mask_16 *network_16 = (struct ipt_account_mask_16 *)ipt_account_handles[handle].data;
 551         unsigned int b;
 552
 553         for (b = 0; b <= 255; b++)
 554         {
 555             if (src_16->mask_24[b])
 556             {
 557                 if ((network_16->mask_24[b] = (void*)get_zeroed_page(GFP_KERNEL)) == NULL)
 558                 {
 559                     printk("ACCOUNT: out of memory during copy of 16 bit network in ipt_account_handle_prepare_read()\n");
 560                     ipt_account_data_free(ipt_account_handles[handle].data, depth);
 561                     memset (&ipt_account_handles[handle], 0, sizeof(struct ipt_account_handle));
 562                     return -1;
 563                 }
 564
 565                 memcpy(network_16->mask_24[b], src_16->mask_24[b], sizeof(struct ipt_account_mask_24));
 566             }
 567         }
 568     } else if(depth == 2) {
 569         struct ipt_account_mask_8 *src_8 = (struct ipt_account_mask_8 *)ipt_account_tables[table_nr].data;
 570         struct ipt_account_mask_8 *network_8 = (struct ipt_account_mask_8 *)ipt_account_handles[handle].data;
 571         unsigned int a;
 572
 573         for (a = 0; a <= 255; a++)
 574         {
 575             if (src_8->mask_16[a])
 576             {
 577                 if ((network_8->mask_16[a] = (void*)get_zeroed_page(GFP_KERNEL)) == NULL)
 578                 {
 579                     printk("ACCOUNT: out of memory during copy of 24 bit network in ipt_account_handle_prepare_read()\n");
 580                     ipt_account_data_free(ipt_account_handles[handle].data, depth);
 581                     memset (&ipt_account_handles[handle], 0, sizeof(struct ipt_account_handle));
 582                     return -1;
 583                 }
 584
 585                 memcpy(network_8->mask_16[a], src_8->mask_16[a], sizeof(struct ipt_account_mask_16));
 586
 587                 struct ipt_account_mask_16 *src_16 = src_8->mask_16[a];
 588                 struct ipt_account_mask_16 *network_16 = network_8->mask_16[a];
 589                 unsigned int b;
 590
 591                 for (b = 0; b <= 255; b++)
 592                 {
 593                     if (src_16->mask_24[b])
 594                     {
 595                         if ((network_16->mask_24[b] = (void*)get_zeroed_page(GFP_KERNEL)) == NULL)
 596                         {
 597                             printk("ACCOUNT: out of memory during copy of 16 bit network in ipt_account_handle_prepare_read()\n");
 598                             ipt_account_data_free(ipt_account_handles[handle].data, depth);
 599                             memset (&ipt_account_handles[handle], 0, sizeof(struct ipt_account_handle));
 600                             return -1;
 601                         }
 602
 603                         memcpy(network_16->mask_24[b], src_16->mask_24[b], sizeof(struct ipt_account_mask_24));
 604                     }
 605                 }
 606             }
 607         }
 608     }
 609
 610     *count = ipt_account_tables[table_nr].itemcount;
 611     return handle;
 612 }
 613
 614 /* Prepare data for read and flush it */
 615 int ipt_account_handle_prepare_read_flush(char *tablename, unsigned int *count)
 616 {
 617     int handle, i, table_nr=-1;
 618
 619     for (i = 0; i < ACCOUNT_MAX_TABLES; i++)
 620         if (strncmp(ipt_account_tables[i].name, tablename, ACCOUNT_TABLE_NAME_LEN) == 0)
 621         {
 622             table_nr = i;
 623             break;
 624         }
 625
 626     if (table_nr == -1)
 627     {
 628         printk("ACCOUNT: ipt_account_handle_prepare_read_flush(): Table %s not found\n", tablename);
 629         return -1;
 630     }
 631
 632     // Can't find a free handle slot?
 633     if ((handle = ipt_account_handle_find_slot()) == -1)
 634         return -1;
 635
 636     // Fill up handle structure
 637     ipt_account_handles[handle].ip = ipt_account_tables[table_nr].ip;
 638     ipt_account_handles[handle].depth = ipt_account_tables[table_nr].depth;
 639     ipt_account_handles[handle].itemcount = ipt_account_tables[table_nr].itemcount;
 640     ipt_account_handles[handle].data = ipt_account_tables[table_nr].data;
 641     *count = ipt_account_tables[table_nr].itemcount;
 642
 643     // "Flush" table data
 644     ipt_account_tables[table_nr].data = (void*)get_zeroed_page(GFP_KERNEL);
 645     ipt_account_tables[table_nr].itemcount = 0;
 646
 647     return handle;
 648 }
 649
 650 /* Copy the actual that into a prepared buffer.
 651    We only copy entries != 0 to increase performance.
 652    The memory gets freed again in ipt_account_handle_free().
 653 */
 654 int ipt_account_handle_get_data(unsigned int handle, void *buffer)
 655 {
 656     struct ipt_account_handle_ip handle_ip;
 657     unsigned int handle_ip_size = sizeof (struct ipt_account_handle_ip);
 658     unsigned int i, tmpbuf_pos=0;
 659
 660     if (handle >= ACCOUNT_MAX_HANDLES)
 661     {
 662         printk("ACCOUNT: invalid handle for ipt_account_handle_get_data() specified: %u\n", handle);
 663         return -1;
 664     }
 665
 666     if (ipt_account_handles[handle].data == NULL)
 667     {
 668         printk("ACCOUNT: handle %u is BROKEN: Contains no data\n", handle);
 669         return -1;
 670     }
 671
 672     unsigned int net_ip = ipt_account_handles[handle].ip;
 673     unsigned int depth = ipt_account_handles[handle].depth;
 674
 675     // 8 bit network
 676     if (depth == 0)
 677     {
 678         struct ipt_account_mask_24 *network = (struct ipt_account_mask_24*)ipt_account_handles[handle].data;
 679         for (i = 0; i <= 255; i++)
 680         {
 681             if (network->ip[i].src_packets || network->ip[i].dst_packets)
 682             {
 683                 handle_ip.ip = net_ip | (i<<24);
 684                 handle_ip.src_packets = network->ip[i].src_packets;
 685                 handle_ip.src_bytes = network->ip[i].src_bytes;
 686                 handle_ip.dst_packets = network->ip[i].dst_packets;
 687                 handle_ip.dst_bytes = network->ip[i].dst_bytes;
 688
 689                 // Temporary buffer full? Flush to userspace
 690                 if (tmpbuf_pos+handle_ip_size >= PAGE_SIZE)
 691                 {
 692                     copy_to_user(buffer, ipt_account_tmpbuf, tmpbuf_pos);
 693                     tmpbuf_pos = 0;
 694                 }
 695                 memcpy(ipt_account_tmpbuf+tmpbuf_pos, &handle_ip, handle_ip_size);
 696                 tmpbuf_pos += handle_ip_size;
 697             }
 698         }
 699
 700         // Flush remaining data to userspace
 701         if (tmpbuf_pos)
 702             copy_to_user(buffer, ipt_account_tmpbuf, tmpbuf_pos);
 703
 704         return 0;
 705     }
 706
 707     // 16 bit network
 708     if (depth == 1)
 709     {
 710         struct ipt_account_mask_16 *network_16 = (struct ipt_account_mask_16*)ipt_account_handles[handle].data;
 711         unsigned int b;
 712         for (b = 0; b <= 255; b++)
 713         {
 714             if (network_16->mask_24[b])
 715             {
 716                 struct ipt_account_mask_24 *network = (struct ipt_account_mask_24*)network_16->mask_24[b];
 717                 for (i = 0; i <= 255; i++)
 718                 {
 719                     if (network->ip[i].src_packets || network->ip[i].dst_packets)
 720                     {
 721                         handle_ip.ip = net_ip | (b << 16) | (i<<24);
 722                         handle_ip.src_packets = network->ip[i].src_packets;
 723                         handle_ip.src_bytes = network->ip[i].src_bytes;
 724                         handle_ip.dst_packets = network->ip[i].dst_packets;
 725                         handle_ip.dst_bytes = network->ip[i].dst_bytes;
 726
 727                         // Temporary buffer full? Flush to userspace
 728                         if (tmpbuf_pos+handle_ip_size >= PAGE_SIZE)
 729                         {
 730                             copy_to_user(buffer, ipt_account_tmpbuf, tmpbuf_pos);
 731                             tmpbuf_pos = 0;
 732                         }
 733                         memcpy(ipt_account_tmpbuf+tmpbuf_pos, &handle_ip, handle_ip_size);
 734                         tmpbuf_pos += handle_ip_size;
 735                     }
 736                 }
 737             }
 738         }
 739
 740         // Flush remaining data to userspace
 741         if (tmpbuf_pos)
 742             copy_to_user(buffer, ipt_account_tmpbuf, tmpbuf_pos);
 743
 744         return 0;
 745     }
 746
 747     // 24 bit network
 748     if (depth == 2)
 749     {
 750         struct ipt_account_mask_8 *network_8 = (struct ipt_account_mask_8*)ipt_account_handles[handle].data;
 751         unsigned int a, b;
 752         for (a = 0; a <= 255; a++)
 753         {
 754             if (network_8->mask_16[a])
 755             {
 756                 struct ipt_account_mask_16 *network_16 = (struct ipt_account_mask_16*)network_8->mask_16[a];
 757                 for (b = 0; b <= 255; b++)
 758                 {
 759                     if (network_16->mask_24[b])
 760                     {
 761                         struct ipt_account_mask_24 *network = (struct ipt_account_mask_24*)network_16->mask_24[b];
 762                         for (i = 0; i <= 255; i++)
 763                         {
 764                             if (network->ip[i].src_packets || network->ip[i].dst_packets)
 765                             {
 766                                 handle_ip.ip = net_ip | (a << 8) | (b << 16) | (i<<24);
 767                                 handle_ip.src_packets = network->ip[i].src_packets;
 768                                 handle_ip.src_bytes = network->ip[i].src_bytes;
 769                                 handle_ip.dst_packets = network->ip[i].dst_packets;
 770                                 handle_ip.dst_bytes = network->ip[i].dst_bytes;
 771
 772                                 // Temporary buffer full? Flush to userspace
 773                                 if (tmpbuf_pos+handle_ip_size >= PAGE_SIZE)
 774                                 {
 775                                     copy_to_user(buffer, ipt_account_tmpbuf, tmpbuf_pos);
 776                                     tmpbuf_pos = 0;
 777                                 }
 778                                 memcpy(ipt_account_tmpbuf+tmpbuf_pos, &handle_ip, handle_ip_size);
 779                                 tmpbuf_pos += handle_ip_size;
 780                             }
 781                         }
 782                     }
 783                 }
 784             }
 785         }
 786
 787         // Flush remaining data to userspace
 788         if (tmpbuf_pos)
 789             copy_to_user(buffer, ipt_account_tmpbuf, tmpbuf_pos);
 790
 791         return 0;
 792     }
 793
 794     return -1;
 795 }
 796
 797 static int ipt_account_set_ctl(struct sock *sk, int cmd, void *user, unsigned int len)
 798 {
 799     struct ipt_account_handle_sockopt handle;
 800     int ret = -EINVAL;
 801
 802     if (!capable(CAP_NET_ADMIN))
 803             return -EPERM;
 804
 805     switch (cmd)
 806     {
 807         case IPT_SO_SET_ACCOUNT_HANDLE_FREE:
 808             if (len != sizeof(struct ipt_account_handle_sockopt))
 809             {
 810                 printk("ACCOUNT: ipt_account_set_ctl: wrong data size (%u != %u) for IPT_SO_SET_HANDLE_FREE\n", len, sizeof(struct ipt_account_handle_sockopt));
 811                 break;
 812             }
 813
 814             if (copy_from_user (&handle, user, len))
 815             {
 816                 printk("ACCOUNT: ipt_account_set_ctl: copy_from_user failed for IPT_SO_SET_HANDLE_FREE\n");
 817                 break;
 818             }
 819
 820             spin_lock_bh(&ipt_account_userspace_lock);
 821             ret = ipt_account_handle_free(handle.handle_nr);
 822             spin_unlock_bh(&ipt_account_userspace_lock);
 823             break;
 824         case IPT_SO_SET_ACCOUNT_HANDLE_FREE_ALL:
 825         {
 826             unsigned int i;
 827             spin_lock_bh(&ipt_account_userspace_lock);
 828             for (i = 0; i < ACCOUNT_MAX_HANDLES; i++)
 829                 ipt_account_handle_free(i);
 830             spin_unlock_bh(&ipt_account_userspace_lock);
 831             ret = 0;
 832             break;
 833         }
 834         default:
 835             printk("ACCOUNT: ipt_account_set_ctl: unknown request %i\n", cmd);
 836     }
 837
 838     return ret;
 839 }
 840
 841 static int ipt_account_get_ctl(struct sock *sk, int cmd, void *user, int *len)
 842 {
 843     struct ipt_account_handle_sockopt handle;
 844     int ret = -EINVAL;
 845
 846     if (!capable(CAP_NET_ADMIN))
 847             return -EPERM;
 848
 849     switch (cmd)
 850     {
 851         case IPT_SO_GET_ACCOUNT_PREPARE_READ_FLUSH:
 852         case IPT_SO_GET_ACCOUNT_PREPARE_READ:
 853             if (*len < sizeof(struct ipt_account_handle_sockopt))
 854             {
 855                 printk("ACCOUNT: ipt_account_get_ctl: wrong data size (%u != %u) for IPT_SO_GET_ACCOUNT_PREPARE_READ/READ_FLUSH\n",
 856                        *len, sizeof(struct ipt_account_handle_sockopt));
 857                 break;
 858             }
 859
 860             if (copy_from_user (&handle, user, sizeof(struct ipt_account_handle_sockopt)))
 861             {
 862                 printk("ACCOUNT: ipt_account_get_ctl: copy_from_user failed for IPT_SO_GET_ACCOUNT_PREPARE_READ/READ_FLUSH\n");
 863                 break;
 864             }
 865
 866             spin_lock_bh(&ipt_account_lock);
 867             spin_lock_bh(&ipt_account_userspace_lock);
 868             if (cmd == IPT_SO_GET_ACCOUNT_PREPARE_READ_FLUSH)
 869                 handle.handle_nr = ipt_account_handle_prepare_read_flush(handle.name, &handle.itemcount);
 870             else
 871                 handle.handle_nr = ipt_account_handle_prepare_read(handle.name, &handle.itemcount);
 872             spin_unlock_bh(&ipt_account_userspace_lock);
 873             spin_unlock_bh(&ipt_account_lock);
 874
 875             if (handle.handle_nr == -1)
 876             {
 877                 printk("ACCOUNT: ipt_account_get_ctl: ipt_account_handle_prepare_read failed\n");
 878                 break;
 879             }
 880
 881             if (copy_to_user(user, &handle, sizeof(struct ipt_account_handle_sockopt)))
 882             {
 883                 printk("ACCOUNT: ipt_account_set_ctl: copy_to_user failed for IPT_SO_GET_ACCOUNT_PREPARE_READ/READ_FLUSH\n");
 884                 break;
 885             }
 886             ret = 0;
 887             break;
 888         case IPT_SO_GET_ACCOUNT_GET_DATA:
 889             if (*len < sizeof(struct ipt_account_handle_sockopt))
 890             {
 891                 printk("ACCOUNT: ipt_account_get_ctl: wrong data size (%u != %u) for IPT_SO_GET_ACCOUNT_PREPARE_READ/READ_FLUSH\n",
 892                        *len, sizeof(struct ipt_account_handle_sockopt));
 893                 break;
 894             }
 895
 896             if (copy_from_user (&handle, user, sizeof(struct ipt_account_handle_sockopt)))
 897             {
 898                 printk("ACCOUNT: ipt_account_get_ctl: copy_from_user failed for IPT_SO_GET_ACCOUNT_PREPARE_READ/READ_FLUSH\n");
 899                 break;
 900             }
 901
 902             if (handle.handle_nr >= ACCOUNT_MAX_HANDLES)
 903             {
 904                 printk("ACCOUNT: Invalid handle for IPT_SO_GET_ACCOUNT_GET_DATA: %u\n", handle.handle_nr);
 905                 break;
 906             }
 907
 908             if (*len < ipt_account_handles[handle.handle_nr].itemcount*sizeof(struct ipt_account_handle_ip))
 909             {
 910                 printk("ACCOUNT: ipt_account_get_ctl: not enough space (%u < %u) to store data from IPT_SO_GET_ACCOUNT_GET_DATA\n",
 911                        *len, ipt_account_handles[handle.handle_nr].itemcount*sizeof(struct ipt_account_handle_ip));
 912                 ret = -ENOMEM;
 913                 break;
 914             }
 915
 916             spin_lock_bh(&ipt_account_userspace_lock);
 917             ret = ipt_account_handle_get_data(handle.handle_nr, user);
 918             spin_unlock_bh(&ipt_account_userspace_lock);
 919             if (ret)
 920             {
 921                 printk("ACCOUNT: ipt_account_get_ctl: ipt_account_handle_get_data failed for handle %u\n", handle.handle_nr);
 922                 break;
 923             }
 924
 925             ret = 0;
 926             break;
 927         case IPT_SO_GET_ACCOUNT_GET_HANDLE_USAGE:
 928         {
 929             if (*len < sizeof(struct ipt_account_handle_sockopt))
 930             {
 931                 printk("ACCOUNT: ipt_account_get_ctl: wrong data size (%u != %u) for IPT_SO_GET_ACCOUNT_GET_HANDLE_USAGE\n",
 932                        *len, sizeof(struct ipt_account_handle_sockopt));
 933                 break;
 934             }
 935
 936             // Find out how many handles are in use
 937             unsigned int i;
 938             handle.itemcount = 0;
 939             spin_lock_bh(&ipt_account_userspace_lock);
 940             for (i = 0; i < ACCOUNT_MAX_HANDLES; i++)
 941                 if (ipt_account_handles[i].data)
 942                     handle.itemcount++;
 943             spin_unlock_bh(&ipt_account_userspace_lock);
 944
 945             if (copy_to_user(user, &handle, sizeof(struct ipt_account_handle_sockopt)))
 946             {
 947                 printk("ACCOUNT: ipt_account_set_ctl: copy_to_user failed for IPT_SO_GET_ACCOUNT_GET_HANDLE_USAGE\n");
 948                 break;
 949             }
 950             ret = 0;
 951             break;
 952         }
 953         case IPT_SO_GET_ACCOUNT_GET_TABLE_NAMES:
 954         {
 955             spin_lock_bh(&ipt_account_lock);
 956
 957             // Determine size of table names
 958             unsigned int size = 0, i;
 959             for (i = 0; i < ACCOUNT_MAX_TABLES; i++)
 960             {
 961                 if (ipt_account_tables[i].name[0] != 0)
 962                     size += strlen (ipt_account_tables[i].name) + 1;
 963             }
 964             size += 1;    // Terminating NULL character
 965
 966             if (*len < size)
 967             {
 968                 spin_unlock_bh(&ipt_account_lock);
 969                 printk("ACCOUNT: ipt_account_get_ctl: not enough space (%u < %u) to store table names\n", *len, size);
 970                 ret = -ENOMEM;
 971                 break;
 972             }
 973             // Copy table names to userspace
 974             char *tnames = user;
 975             for (i = 0; i < ACCOUNT_MAX_TABLES; i++)
 976             {
 977                 if (ipt_account_tables[i].name[0] != 0)
 978                 {
 979                     int len = strlen (ipt_account_tables[i].name) + 1;
 980                     copy_to_user(tnames, ipt_account_tables[i].name, len);    // copy string + terminating zero
 981                     tnames += len;
 982                 }
 983             }
 984             // Append terminating zero
 985             i = 0;
 986             copy_to_user(tnames, &i, 1);
 987             spin_unlock_bh(&ipt_account_lock);
 988             ret = 0;
 989             break;
 990         }
 991         default:
 992             printk("ACCOUNT: ipt_account_get_ctl: unknown request %i\n", cmd);
 993     }
 994
 995     return ret;
 996 }
 997
 998 static struct ipt_target ipt_account_reg
 999 = { { NULL, NULL }, "ACCOUNT", ipt_account_target, ipt_account_checkentry, ipt_account_deleteentry,
1000     THIS_MODULE };
1001
1002 static struct nf_sockopt_ops ipt_account_sockopts
1003 = { { NULL, NULL }, PF_INET, IPT_SO_SET_ACCOUNT_HANDLE_FREE, IPT_SO_SET_ACCOUNT_MAX+1, ipt_account_set_ctl,
1004     IPT_SO_GET_ACCOUNT_PREPARE_READ, IPT_SO_GET_ACCOUNT_MAX+1, ipt_account_get_ctl, 0, NULL  };
1005
1006 static int __init init(void)
1007 {
1008     if (PAGE_SIZE < 4096)
1009     {
1010         printk("ACCOUNT: Sorry we need at least a PAGE_SIZE of 4096. Found: %lu\n", PAGE_SIZE);
1011         return -EINVAL;
1012     }
1013
1014     if ((ipt_account_tables = kmalloc(ACCOUNT_MAX_TABLES*sizeof(struct ipt_account_table), GFP_KERNEL)) == NULL)
1015     {
1016         printk("ACCOUNT: Out of memory allocating account_tables structure");
1017         return -EINVAL;
1018     }
1019     memset(ipt_account_tables, 0, ACCOUNT_MAX_TABLES*sizeof(struct ipt_account_table));
1020
1021     if ((ipt_account_handles = kmalloc(ACCOUNT_MAX_HANDLES*sizeof(struct ipt_account_handle), GFP_KERNEL)) == NULL)
1022     {
1023         printk("ACCOUNT: Out of memory allocating account_handles structure");
1024         kfree (ipt_account_tables);
1025         ipt_account_tables = NULL;
1026         return -EINVAL;
1027     }
1028     memset(ipt_account_handles, 0, ACCOUNT_MAX_HANDLES*sizeof(struct ipt_account_handle));
1029
1030     // Allocate one page as temporary storage
1031     if ((ipt_account_tmpbuf = (void*)__get_free_page(GFP_KERNEL)) == NULL)
1032     {
1033         printk("ACCOUNT: Out of memory for temporary buffer page\n");
1034         kfree(ipt_account_tables);
1035         kfree(ipt_account_handles);
1036         ipt_account_tables = NULL;
1037         ipt_account_handles = NULL;
1038         return -EINVAL;
1039     }
1040
1041     /* Register setsockopt */
1042     if (nf_register_sockopt(&ipt_account_sockopts) < 0)
1043     {
1044         printk("ACCOUNT: Can't register sockopts. Aborting\n");
1045
1046         kfree(ipt_account_tables);
1047         kfree(ipt_account_handles);
1048         free_page((unsigned long)ipt_account_tmpbuf);
1049         ipt_account_tables = NULL;
1050         ipt_account_handles = NULL;
1051         ipt_account_tmpbuf = NULL;
1052
1053         return -EINVAL;
1054     }
1055
1056     if (ipt_register_target(&ipt_account_reg))
1057             return -EINVAL;
1058
1059     return 0;
1060 }
1061
1062 static void __exit fini(void)
1063 {
1064     ipt_unregister_target(&ipt_account_reg);
1065
1066     nf_unregister_sockopt(&ipt_account_sockopts);
1067
1068     kfree(ipt_account_tables);
1069     kfree(ipt_account_handles);
1070     free_page((unsigned long)ipt_account_tmpbuf);
1071
1072     ipt_account_tables = NULL;
1073     ipt_account_handles = NULL;
1074     ipt_account_tmpbuf = NULL;
1075 }
1076
1077 module_init(init);
1078 module_exit(fini);
1079 MODULE_LICENSE("GPL");