target/linux/generic-2.6/patches-2.6.25/100-netfilter_layer7_2.17.patch

   1 --- a/net/netfilter/Kconfig
   2 +++ b/net/netfilter/Kconfig
   3 @@ -735,6 +735,27 @@
   4
   5           To compile it as a module, choose M here.  If unsure, say N.
   6
   7 +config NETFILTER_XT_MATCH_LAYER7
   8 +       tristate '"layer7" match support'
   9 +       depends on NETFILTER_XTABLES
  10 +       depends on EXPERIMENTAL && (IP_NF_CONNTRACK || NF_CONNTRACK)
  11 +       depends on NF_CT_ACCT
  12 +       help
  13 +         Say Y if you want to be able to classify connections (and their
  14 +         packets) based on regular expression matching of their application
  15 +         layer data.   This is one way to classify applications such as
  16 +         peer-to-peer filesharing systems that do not always use the same
  17 +         port.
  18 +
  19 +         To compile it as a module, choose M here.  If unsure, say N.
  20 +
  21 +config NETFILTER_XT_MATCH_LAYER7_DEBUG
  22 +        bool 'Layer 7 debugging output'
  23 +        depends on NETFILTER_XT_MATCH_LAYER7
  24 +        help
  25 +          Say Y to get lots of debugging output.
  26 +
  27 +
  28  config NETFILTER_XT_MATCH_STATISTIC
  29         tristate '"statistic" match support'
  30         depends on NETFILTER_XTABLES
  31 --- a/net/netfilter/Makefile
  32 +++ b/net/netfilter/Makefile
  33 @@ -77,6 +77,7 @@
  34  obj-$(CONFIG_NETFILTER_XT_MATCH_REALM) += xt_realm.o
  35  obj-$(CONFIG_NETFILTER_XT_MATCH_SCTP) += xt_sctp.o
  36  obj-$(CONFIG_NETFILTER_XT_MATCH_STATE) += xt_state.o
  37 +obj-$(CONFIG_NETFILTER_XT_MATCH_LAYER7) += xt_layer7.o
  38  obj-$(CONFIG_NETFILTER_XT_MATCH_STATISTIC) += xt_statistic.o
  39  obj-$(CONFIG_NETFILTER_XT_MATCH_STRING) += xt_string.o
  40  obj-$(CONFIG_NETFILTER_XT_MATCH_TCPMSS) += xt_tcpmss.o
  41 --- /dev/null
  42 +++ b/net/netfilter/xt_layer7.c
  43 @@ -0,0 +1,634 @@
  44 +/*
  45 +  Kernel module to match application layer (OSI layer 7) data in connections.
  46 +
  47 +  http://l7-filter.sf.net
  48 +
  49 +  (C) 2003, 2004, 2005, 2006, 2007 Matthew Strait and Ethan Sommer.
  50 +
  51 +  This program is free software; you can redistribute it and/or
  52 +  modify it under the terms of the GNU General Public License
  53 +  as published by the Free Software Foundation; either version
  54 +  2 of the License, or (at your option) any later version.
  55 +  http://www.gnu.org/licenses/gpl.txt
  56 +
  57 +  Based on ipt_string.c (C) 2000 Emmanuel Roger <winfield@freegates.be>,
  58 +  xt_helper.c (C) 2002 Harald Welte and cls_layer7.c (C) 2003 Matthew Strait,
  59 +  Ethan Sommer, Justin Levandoski.
  60 +*/
  61 +
  62 +#include <linux/spinlock.h>
  63 +#include <linux/version.h>
  64 +#include <net/ip.h>
  65 +#include <net/tcp.h>
  66 +#include <linux/module.h>
  67 +#include <linux/skbuff.h>
  68 +#include <linux/netfilter.h>
  69 +#include <net/netfilter/nf_conntrack.h>
  70 +#include <net/netfilter/nf_conntrack_core.h>
  71 +#include <linux/netfilter/x_tables.h>
  72 +#include <linux/netfilter/xt_layer7.h>
  73 +#include <linux/ctype.h>
  74 +#include <linux/proc_fs.h>
  75 +
  76 +#include "regexp/regexp.c"
  77 +
  78 +MODULE_LICENSE("GPL");
  79 +MODULE_AUTHOR("Matthew Strait <quadong@users.sf.net>, Ethan Sommer <sommere@users.sf.net>");
  80 +MODULE_DESCRIPTION("iptables application layer match module");
  81 +MODULE_ALIAS("ipt_layer7");
  82 +MODULE_VERSION("2.17");
  83 +
  84 +static int maxdatalen = 2048; // this is the default
  85 +module_param(maxdatalen, int, 0444);
  86 +MODULE_PARM_DESC(maxdatalen, "maximum bytes of data looked at by l7-filter");
  87 +#ifdef CONFIG_NETFILTER_XT_MATCH_LAYER7_DEBUG
  88 +       #define DPRINTK(format,args...) printk(format,##args)
  89 +#else
  90 +       #define DPRINTK(format,args...)
  91 +#endif
  92 +
  93 +#define TOTAL_PACKETS master_conntrack->counters[IP_CT_DIR_ORIGINAL].packets + \
  94 +                     master_conntrack->counters[IP_CT_DIR_REPLY].packets
  95 +
  96 +/* Number of packets whose data we look at.
  97 +This can be modified through /proc/net/layer7_numpackets */
  98 +static int num_packets = 10;
  99 +
 100 +static struct pattern_cache {
 101 +       char * regex_string;
 102 +       regexp * pattern;
 103 +       struct pattern_cache * next;
 104 +} * first_pattern_cache = NULL;
 105 +
 106 +DEFINE_SPINLOCK(l7_lock);
 107 +
 108 +#ifdef CONFIG_IP_NF_MATCH_LAYER7_DEBUG
 109 +/* Converts an unfriendly string into a friendly one by
 110 +replacing unprintables with periods and all whitespace with " ". */
 111 +static char * friendly_print(unsigned char * s)
 112 +{
 113 +       char * f = kmalloc(strlen(s) + 1, GFP_ATOMIC);
 114 +       int i;
 115 +
 116 +       if(!f) {
 117 +               if (net_ratelimit())
 118 +                       printk(KERN_ERR "layer7: out of memory in "
 119 +                                       "friendly_print, bailing.\n");
 120 +               return NULL;
 121 +       }
 122 +
 123 +       for(i = 0; i < strlen(s); i++){
 124 +               if(isprint(s[i]) && s[i] < 128) f[i] = s[i];
 125 +               else if(isspace(s[i]))          f[i] = ' ';
 126 +               else                            f[i] = '.';
 127 +       }
 128 +       f[i] = '\0';
 129 +       return f;
 130 +}
 131 +
 132 +static char dec2hex(int i)
 133 +{
 134 +       switch (i) {
 135 +               case 0 ... 9:
 136 +                       return (i + '0');
 137 +                       break;
 138 +               case 10 ... 15:
 139 +                       return (i - 10 + 'a');
 140 +                       break;
 141 +               default:
 142 +                       if (net_ratelimit())
 143 +                               printk("layer7: Problem in dec2hex\n");
 144 +                       return '\0';
 145 +       }
 146 +}
 147 +
 148 +static char * hex_print(unsigned char * s)
 149 +{
 150 +       char * g = kmalloc(strlen(s)*3 + 1, GFP_ATOMIC);
 151 +       int i;
 152 +
 153 +       if(!g) {
 154 +              if (net_ratelimit())
 155 +                       printk(KERN_ERR "layer7: out of memory in hex_print, "
 156 +                                       "bailing.\n");
 157 +              return NULL;
 158 +       }
 159 +
 160 +       for(i = 0; i < strlen(s); i++) {
 161 +               g[i*3    ] = dec2hex(s[i]/16);
 162 +               g[i*3 + 1] = dec2hex(s[i]%16);
 163 +               g[i*3 + 2] = ' ';
 164 +       }
 165 +       g[i*3] = '\0';
 166 +
 167 +       return g;
 168 +}
 169 +#endif // DEBUG
 170 +
 171 +/* Use instead of regcomp.  As we expect to be seeing the same regexps over and
 172 +over again, it make sense to cache the results. */
 173 +static regexp * compile_and_cache(const char * regex_string,
 174 +                                  const char * protocol)
 175 +{
 176 +       struct pattern_cache * node               = first_pattern_cache;
 177 +       struct pattern_cache * last_pattern_cache = first_pattern_cache;
 178 +       struct pattern_cache * tmp;
 179 +       unsigned int len;
 180 +
 181 +       while (node != NULL) {
 182 +               if (!strcmp(node->regex_string, regex_string))
 183 +               return node->pattern;
 184 +
 185 +               last_pattern_cache = node;/* points at the last non-NULL node */
 186 +               node = node->next;
 187 +       }
 188 +
 189 +       /* If we reach the end of the list, then we have not yet cached
 190 +          the pattern for this regex. Let's do that now.
 191 +          Be paranoid about running out of memory to avoid list corruption. */
 192 +       tmp = kmalloc(sizeof(struct pattern_cache), GFP_ATOMIC);
 193 +
 194 +       if(!tmp) {
 195 +               if (net_ratelimit())
 196 +                       printk(KERN_ERR "layer7: out of memory in "
 197 +                                       "compile_and_cache, bailing.\n");
 198 +               return NULL;
 199 +       }
 200 +
 201 +       tmp->regex_string  = kmalloc(strlen(regex_string) + 1, GFP_ATOMIC);
 202 +       tmp->pattern       = kmalloc(sizeof(struct regexp),    GFP_ATOMIC);
 203 +       tmp->next = NULL;
 204 +
 205 +       if(!tmp->regex_string || !tmp->pattern) {
 206 +               if (net_ratelimit())
 207 +                       printk(KERN_ERR "layer7: out of memory in "
 208 +                                       "compile_and_cache, bailing.\n");
 209 +               kfree(tmp->regex_string);
 210 +               kfree(tmp->pattern);
 211 +               kfree(tmp);
 212 +               return NULL;
 213 +       }
 214 +
 215 +       /* Ok.  The new node is all ready now. */
 216 +       node = tmp;
 217 +
 218 +       if(first_pattern_cache == NULL) /* list is empty */
 219 +               first_pattern_cache = node; /* make node the beginning */
 220 +       else
 221 +               last_pattern_cache->next = node; /* attach node to the end */
 222 +
 223 +       /* copy the string and compile the regex */
 224 +       len = strlen(regex_string);
 225 +       DPRINTK("About to compile this: \"%s\"\n", regex_string);
 226 +       node->pattern = regcomp((char *)regex_string, &len);
 227 +       if ( !node->pattern ) {
 228 +               if (net_ratelimit())
 229 +                       printk(KERN_ERR "layer7: Error compiling regexp "
 230 +                                       "\"%s\" (%s)\n",
 231 +                                       regex_string, protocol);
 232 +               /* pattern is now cached as NULL, so we won't try again. */
 233 +       }
 234 +
 235 +       strcpy(node->regex_string, regex_string);
 236 +       return node->pattern;
 237 +}
 238 +
 239 +static int can_handle(const struct sk_buff *skb)
 240 +{
 241 +       if(!ip_hdr(skb)) /* not IP */
 242 +               return 0;
 243 +       if(ip_hdr(skb)->protocol != IPPROTO_TCP &&
 244 +          ip_hdr(skb)->protocol != IPPROTO_UDP &&
 245 +          ip_hdr(skb)->protocol != IPPROTO_ICMP)
 246 +               return 0;
 247 +       return 1;
 248 +}
 249 +
 250 +/* Returns offset the into the skb->data that the application data starts */
 251 +static int app_data_offset(const struct sk_buff *skb)
 252 +{
 253 +       /* In case we are ported somewhere (ebtables?) where ip_hdr(skb)
 254 +       isn't set, this can be gotten from 4*(skb->data[0] & 0x0f) as well. */
 255 +       int ip_hl = 4*ip_hdr(skb)->ihl;
 256 +
 257 +       if( ip_hdr(skb)->protocol == IPPROTO_TCP ) {
 258 +               /* 12 == offset into TCP header for the header length field.
 259 +               Can't get this with skb->h.th->doff because the tcphdr
 260 +               struct doesn't get set when routing (this is confirmed to be
 261 +               true in Netfilter as well as QoS.) */
 262 +               int tcp_hl = 4*(skb->data[ip_hl + 12] >> 4);
 263 +
 264 +               return ip_hl + tcp_hl;
 265 +       } else if( ip_hdr(skb)->protocol == IPPROTO_UDP  ) {
 266 +               return ip_hl + 8; /* UDP header is always 8 bytes */
 267 +       } else if( ip_hdr(skb)->protocol == IPPROTO_ICMP ) {
 268 +               return ip_hl + 8; /* ICMP header is 8 bytes */
 269 +       } else {
 270 +               if (net_ratelimit())
 271 +                       printk(KERN_ERR "layer7: tried to handle unknown "
 272 +                                       "protocol!\n");
 273 +               return ip_hl + 8; /* something reasonable */
 274 +       }
 275 +}
 276 +
 277 +/* handles whether there's a match when we aren't appending data anymore */
 278 +static int match_no_append(struct nf_conn * conntrack,
 279 +                           struct nf_conn * master_conntrack,
 280 +                           enum ip_conntrack_info ctinfo,
 281 +                           enum ip_conntrack_info master_ctinfo,
 282 +                           const struct xt_layer7_info * info)
 283 +{
 284 +       /* If we're in here, throw the app data away */
 285 +       if(master_conntrack->layer7.app_data != NULL) {
 286 +
 287 +       #ifdef CONFIG_IP_NF_MATCH_LAYER7_DEBUG
 288 +               if(!master_conntrack->layer7.app_proto) {
 289 +                       char * f =
 290 +                         friendly_print(master_conntrack->layer7.app_data);
 291 +                       char * g =
 292 +                         hex_print(master_conntrack->layer7.app_data);
 293 +                       DPRINTK("\nl7-filter gave up after %d bytes "
 294 +                               "(%d packets):\n%s\n",
 295 +                               strlen(f), TOTAL_PACKETS, f);
 296 +                       kfree(f);
 297 +                       DPRINTK("In hex: %s\n", g);
 298 +                       kfree(g);
 299 +               }
 300 +       #endif
 301 +
 302 +               kfree(master_conntrack->layer7.app_data);
 303 +               master_conntrack->layer7.app_data = NULL; /* don't free again */
 304 +       }
 305 +
 306 +       if(master_conntrack->layer7.app_proto){
 307 +               /* Here child connections set their .app_proto (for /proc) */
 308 +               if(!conntrack->layer7.app_proto) {
 309 +                       conntrack->layer7.app_proto =
 310 +                         kmalloc(strlen(master_conntrack->layer7.app_proto)+1,
 311 +                           GFP_ATOMIC);
 312 +                       if(!conntrack->layer7.app_proto){
 313 +                               if (net_ratelimit())
 314 +                                       printk(KERN_ERR "layer7: out of memory "
 315 +                                                       "in match_no_append, "
 316 +                                                       "bailing.\n");
 317 +                               return 1;
 318 +                       }
 319 +                       strcpy(conntrack->layer7.app_proto,
 320 +                               master_conntrack->layer7.app_proto);
 321 +               }
 322 +
 323 +               return (!strcmp(master_conntrack->layer7.app_proto,
 324 +                               info->protocol));
 325 +       }
 326 +       else {
 327 +               /* If not classified, set to "unknown" to distinguish from
 328 +               connections that are still being tested. */
 329 +               master_conntrack->layer7.app_proto =
 330 +                       kmalloc(strlen("unknown")+1, GFP_ATOMIC);
 331 +               if(!master_conntrack->layer7.app_proto){
 332 +                       if (net_ratelimit())
 333 +                               printk(KERN_ERR "layer7: out of memory in "
 334 +                                               "match_no_append, bailing.\n");
 335 +                       return 1;
 336 +               }
 337 +               strcpy(master_conntrack->layer7.app_proto, "unknown");
 338 +               return 0;
 339 +       }
 340 +}
 341 +
 342 +/* add the new app data to the conntrack.  Return number of bytes added. */
 343 +static int add_data(struct nf_conn * master_conntrack,
 344 +                    char * app_data, int appdatalen)
 345 +{
 346 +       int length = 0, i;
 347 +       int oldlength = master_conntrack->layer7.app_data_len;
 348 +
 349 +       /* This is a fix for a race condition by Deti Fliegl. However, I'm not
 350 +          clear on whether the race condition exists or whether this really
 351 +          fixes it.  I might just be being dense... Anyway, if it's not really
 352 +          a fix, all it does is waste a very small amount of time. */
 353 +       if(!master_conntrack->layer7.app_data) return 0;
 354 +
 355 +       /* Strip nulls. Make everything lower case (our regex lib doesn't
 356 +       do case insensitivity).  Add it to the end of the current data. */
 357 +       for(i = 0; i < maxdatalen-oldlength-1 &&
 358 +                  i < appdatalen; i++) {
 359 +               if(app_data[i] != '\0') {
 360 +                       /* the kernel version of tolower mungs 'upper ascii' */
 361 +                       master_conntrack->layer7.app_data[length+oldlength] =
 362 +                               isascii(app_data[i])?
 363 +                                       tolower(app_data[i]) : app_data[i];
 364 +                       length++;
 365 +               }
 366 +       }
 367 +
 368 +       master_conntrack->layer7.app_data[length+oldlength] = '\0';
 369 +       master_conntrack->layer7.app_data_len = length + oldlength;
 370 +
 371 +       return length;
 372 +}
 373 +
 374 +/* taken from drivers/video/modedb.c */
 375 +static int my_atoi(const char *s)
 376 +{
 377 +       int val = 0;
 378 +
 379 +       for (;; s++) {
 380 +               switch (*s) {
 381 +                       case '0'...'9':
 382 +                       val = 10*val+(*s-'0');
 383 +                       break;
 384 +               default:
 385 +                       return val;
 386 +               }
 387 +       }
 388 +}
 389 +
 390 +/* write out num_packets to userland. */
 391 +static int layer7_read_proc(char* page, char ** start, off_t off, int count,
 392 +                            int* eof, void * data)
 393 +{
 394 +       if(num_packets > 99 && net_ratelimit())
 395 +               printk(KERN_ERR "layer7: NOT REACHED. num_packets too big\n");
 396 +
 397 +       page[0] = num_packets/10 + '0';
 398 +       page[1] = num_packets%10 + '0';
 399 +       page[2] = '\n';
 400 +       page[3] = '\0';
 401 +
 402 +       *eof=1;
 403 +
 404 +       return 3;
 405 +}
 406 +
 407 +/* Read in num_packets from userland */
 408 +static int layer7_write_proc(struct file* file, const char* buffer,
 409 +                             unsigned long count, void *data)
 410 +{
 411 +       char * foo = kmalloc(count, GFP_ATOMIC);
 412 +
 413 +       if(!foo){
 414 +               if (net_ratelimit())
 415 +                       printk(KERN_ERR "layer7: out of memory, bailing. "
 416 +                                       "num_packets unchanged.\n");
 417 +               return count;
 418 +       }
 419 +
 420 +       if(copy_from_user(foo, buffer, count)) {
 421 +               return -EFAULT;
 422 +       }
 423 +
 424 +
 425 +       num_packets = my_atoi(foo);
 426 +       kfree (foo);
 427 +
 428 +       /* This has an arbitrary limit to make the math easier. I'm lazy.
 429 +       But anyway, 99 is a LOT! If you want more, you're doing it wrong! */
 430 +       if(num_packets > 99) {
 431 +               printk(KERN_WARNING "layer7: num_packets can't be > 99.\n");
 432 +               num_packets = 99;
 433 +       } else if(num_packets < 1) {
 434 +               printk(KERN_WARNING "layer7: num_packets can't be < 1.\n");
 435 +               num_packets = 1;
 436 +       }
 437 +
 438 +       return count;
 439 +}
 440 +
 441 +static bool
 442 +match(const struct sk_buff *skbin,
 443 +      const struct net_device *in,
 444 +      const struct net_device *out,
 445 +      const struct xt_match *match,
 446 +      const void *matchinfo,
 447 +      int offset,
 448 +      unsigned int protoff,
 449 +      bool *hotdrop)
 450 +{
 451 +       /* sidestep const without getting a compiler warning... */
 452 +       struct sk_buff * skb = (struct sk_buff *)skbin;
 453 +
 454 +       const struct xt_layer7_info * info = matchinfo;
 455 +       enum ip_conntrack_info master_ctinfo, ctinfo;
 456 +       struct nf_conn *master_conntrack, *conntrack;
 457 +       unsigned char * app_data;
 458 +       unsigned int pattern_result, appdatalen;
 459 +       regexp * comppattern;
 460 +
 461 +       /* Be paranoid/incompetent - lock the entire match function. */
 462 +       spin_lock_bh(&l7_lock);
 463 +
 464 +       if(!can_handle(skb)){
 465 +               DPRINTK("layer7: This is some protocol I can't handle.\n");
 466 +               spin_unlock_bh(&l7_lock);
 467 +               return info->invert;
 468 +       }
 469 +
 470 +       /* Treat parent & all its children together as one connection, except
 471 +       for the purpose of setting conntrack->layer7.app_proto in the actual
 472 +       connection. This makes /proc/net/ip_conntrack more satisfying. */
 473 +       if(!(conntrack = nf_ct_get(skb, &ctinfo)) ||
 474 +          !(master_conntrack=nf_ct_get(skb,&master_ctinfo))){
 475 +               DPRINTK("layer7: couldn't get conntrack.\n");
 476 +               spin_unlock_bh(&l7_lock);
 477 +               return info->invert;
 478 +       }
 479 +
 480 +       /* Try to get a master conntrack (and its master etc) for FTP, etc. */
 481 +       while (master_ct(master_conntrack) != NULL)
 482 +               master_conntrack = master_ct(master_conntrack);
 483 +
 484 +       /* if we've classified it or seen too many packets */
 485 +       if(TOTAL_PACKETS > num_packets ||
 486 +          master_conntrack->layer7.app_proto) {
 487 +
 488 +               pattern_result = match_no_append(conntrack, master_conntrack,
 489 +                                                ctinfo, master_ctinfo, info);
 490 +
 491 +               /* skb->cb[0] == seen. Don't do things twice if there are
 492 +               multiple l7 rules. I'm not sure that using cb for this purpose
 493 +               is correct, even though it says "put your private variables
 494 +               there". But it doesn't look like it is being used for anything
 495 +               else in the skbs that make it here. */
 496 +               skb->cb[0] = 1; /* marking it seen here's probably irrelevant */
 497 +
 498 +               spin_unlock_bh(&l7_lock);
 499 +               return (pattern_result ^ info->invert);
 500 +       }
 501 +
 502 +       if(skb_is_nonlinear(skb)){
 503 +               if(skb_linearize(skb) != 0){
 504 +                       if (net_ratelimit())
 505 +                               printk(KERN_ERR "layer7: failed to linearize "
 506 +                                               "packet, bailing.\n");
 507 +                       spin_unlock_bh(&l7_lock);
 508 +                       return info->invert;
 509 +               }
 510 +       }
 511 +
 512 +       /* now that the skb is linearized, it's safe to set these. */
 513 +       app_data = skb->data + app_data_offset(skb);
 514 +       appdatalen = skb_tail_pointer(skb) - app_data;
 515 +
 516 +       /* the return value gets checked later, when we're ready to use it */
 517 +       comppattern = compile_and_cache(info->pattern, info->protocol);
 518 +
 519 +       /* On the first packet of a connection, allocate space for app data */
 520 +       if(TOTAL_PACKETS == 1 && !skb->cb[0] &&
 521 +          !master_conntrack->layer7.app_data){
 522 +               master_conntrack->layer7.app_data =
 523 +                       kmalloc(maxdatalen, GFP_ATOMIC);
 524 +               if(!master_conntrack->layer7.app_data){
 525 +                       if (net_ratelimit())
 526 +                               printk(KERN_ERR "layer7: out of memory in "
 527 +                                               "match, bailing.\n");
 528 +                       spin_unlock_bh(&l7_lock);
 529 +                       return info->invert;
 530 +               }
 531 +
 532 +               master_conntrack->layer7.app_data[0] = '\0';
 533 +       }
 534 +
 535 +       /* Can be here, but unallocated, if numpackets is increased near
 536 +       the beginning of a connection */
 537 +       if(master_conntrack->layer7.app_data == NULL){
 538 +               spin_unlock_bh(&l7_lock);
 539 +               return (info->invert); /* unmatched */
 540 +       }
 541 +
 542 +       if(!skb->cb[0]){
 543 +               int newbytes;
 544 +               newbytes = add_data(master_conntrack, app_data, appdatalen);
 545 +
 546 +               if(newbytes == 0) { /* didn't add any data */
 547 +                       skb->cb[0] = 1;
 548 +                       /* Didn't match before, not going to match now */
 549 +                       spin_unlock_bh(&l7_lock);
 550 +                       return info->invert;
 551 +               }
 552 +       }
 553 +
 554 +       /* If looking for "unknown", then never match.  "Unknown" means that
 555 +       we've given up; we're still trying with these packets. */
 556 +       if(!strcmp(info->protocol, "unknown")) {
 557 +               pattern_result = 0;
 558 +       /* If looking for "unset", then always match. "Unset" means that we
 559 +       haven't yet classified the connection. */
 560 +       } else if(!strcmp(info->protocol, "unset")) {
 561 +               pattern_result = 2;
 562 +               DPRINTK("layer7: matched unset: not yet classified "
 563 +                       "(%d/%d packets)\n", TOTAL_PACKETS, num_packets);
 564 +       /* If the regexp failed to compile, don't bother running it */
 565 +       } else if(comppattern &&
 566 +                 regexec(comppattern, master_conntrack->layer7.app_data)){
 567 +               DPRINTK("layer7: matched %s\n", info->protocol);
 568 +               pattern_result = 1;
 569 +       } else pattern_result = 0;
 570 +
 571 +       if(pattern_result == 1) {
 572 +               master_conntrack->layer7.app_proto =
 573 +                       kmalloc(strlen(info->protocol)+1, GFP_ATOMIC);
 574 +               if(!master_conntrack->layer7.app_proto){
 575 +                       if (net_ratelimit())
 576 +                               printk(KERN_ERR "layer7: out of memory in "
 577 +                                               "match, bailing.\n");
 578 +                       spin_unlock_bh(&l7_lock);
 579 +                       return (pattern_result ^ info->invert);
 580 +               }
 581 +               strcpy(master_conntrack->layer7.app_proto, info->protocol);
 582 +       } else if(pattern_result > 1) { /* cleanup from "unset" */
 583 +               pattern_result = 1;
 584 +       }
 585 +
 586 +       /* mark the packet seen */
 587 +       skb->cb[0] = 1;
 588 +
 589 +       spin_unlock_bh(&l7_lock);
 590 +       return (pattern_result ^ info->invert);
 591 +}
 592 +
 593 +static bool check(const char *tablename,
 594 +                const void *inf,
 595 +                const struct xt_match *match,
 596 +                void *matchinfo,
 597 +                unsigned int hook_mask)
 598 +
 599 +{
 600 +       // load nf_conntrack_ipv4
 601 +        if (nf_ct_l3proto_try_module_get(match->family) < 0) {
 602 +                printk(KERN_WARNING "can't load conntrack support for "
 603 +                                    "proto=%d\n", match->family);
 604 +                return false;
 605 +        }
 606 +       return true;
 607 +}
 608 +
 609 +static void
 610 +destroy(const struct xt_match *match, void *matchinfo)
 611 +{
 612 +       nf_ct_l3proto_module_put(match->family);
 613 +}
 614 +
 615 +static struct xt_match xt_layer7_match[] = {
 616 +{
 617 +       .name           = "layer7",
 618 +       .family         = AF_INET,
 619 +       .checkentry     = check,
 620 +       .match          = match,
 621 +       .destroy        = destroy,
 622 +       .matchsize      = sizeof(struct xt_layer7_info),
 623 +       .me             = THIS_MODULE
 624 +}
 625 +};
 626 +
 627 +static void layer7_cleanup_proc(void)
 628 +{
 629 +#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
 630 +       remove_proc_entry("layer7_numpackets", proc_net);
 631 +#else
 632 +       remove_proc_entry("layer7_numpackets", init_net.proc_net);
 633 +#endif
 634 +}
 635 +
 636 +/* register the proc file */
 637 +static void layer7_init_proc(void)
 638 +{
 639 +       struct proc_dir_entry* entry;
 640 +#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
 641 +       entry = create_proc_entry("layer7_numpackets", 0644, proc_net);
 642 +#else
 643 +       entry = create_proc_entry("layer7_numpackets", 0644, init_net.proc_net);
 644 +#endif
 645 +       entry->read_proc = layer7_read_proc;
 646 +       entry->write_proc = layer7_write_proc;
 647 +}
 648 +
 649 +static int __init xt_layer7_init(void)
 650 +{
 651 +       need_conntrack();
 652 +
 653 +       layer7_init_proc();
 654 +       if(maxdatalen < 1) {
 655 +               printk(KERN_WARNING "layer7: maxdatalen can't be < 1, "
 656 +                       "using 1\n");
 657 +               maxdatalen = 1;
 658 +       }
 659 +       /* This is not a hard limit.  It's just here to prevent people from
 660 +       bringing their slow machines to a grinding halt. */
 661 +       else if(maxdatalen > 65536) {
 662 +               printk(KERN_WARNING "layer7: maxdatalen can't be > 65536, "
 663 +                       "using 65536\n");
 664 +               maxdatalen = 65536;
 665 +       }
 666 +       return xt_register_matches(xt_layer7_match,
 667 +                                  ARRAY_SIZE(xt_layer7_match));
 668 +}
 669 +
 670 +static void __exit xt_layer7_fini(void)
 671 +{
 672 +       layer7_cleanup_proc();
 673 +       xt_unregister_matches(xt_layer7_match, ARRAY_SIZE(xt_layer7_match));
 674 +}
 675 +
 676 +module_init(xt_layer7_init);
 677 +module_exit(xt_layer7_fini);
 678 --- /dev/null
 679 +++ b/net/netfilter/regexp/regexp.c
 680 @@ -0,0 +1,1197 @@
 681 +/*
 682 + * regcomp and regexec -- regsub and regerror are elsewhere
 683 + * @(#)regexp.c        1.3 of 18 April 87
 684 + *
 685 + *     Copyright (c) 1986 by University of Toronto.
 686 + *     Written by Henry Spencer.  Not derived from licensed software.
 687 + *
 688 + *     Permission is granted to anyone to use this software for any
 689 + *     purpose on any computer system, and to redistribute it freely,
 690 + *     subject to the following restrictions:
 691 + *
 692 + *     1. The author is not responsible for the consequences of use of
 693 + *             this software, no matter how awful, even if they arise
 694 + *             from defects in it.
 695 + *
 696 + *     2. The origin of this software must not be misrepresented, either
 697 + *             by explicit claim or by omission.
 698 + *
 699 + *     3. Altered versions must be plainly marked as such, and must not
 700 + *             be misrepresented as being the original software.
 701 + *
 702 + * Beware that some of this code is subtly aware of the way operator
 703 + * precedence is structured in regular expressions.  Serious changes in
 704 + * regular-expression syntax might require a total rethink.
 705 + *
 706 + * This code was modified by Ethan Sommer to work within the kernel
 707 + * (it now uses kmalloc etc..)
 708 + *
 709 + * Modified slightly by Matthew Strait to use more modern C.
 710 + */
 711 +
 712 +#include "regexp.h"
 713 +#include "regmagic.h"
 714 +
 715 +/* added by ethan and matt.  Lets it work in both kernel and user space.
 716 +(So iptables can use it, for instance.)  Yea, it goes both ways... */
 717 +#if __KERNEL__
 718 +  #define malloc(foo) kmalloc(foo,GFP_ATOMIC)
 719 +#else
 720 +  #define printk(format,args...) printf(format,##args)
 721 +#endif
 722 +
 723 +void regerror(char * s)
 724 +{
 725 +        printk("<3>Regexp: %s\n", s);
 726 +        /* NOTREACHED */
 727 +}
 728 +
 729 +/*
 730 + * The "internal use only" fields in regexp.h are present to pass info from
 731 + * compile to execute that permits the execute phase to run lots faster on
 732 + * simple cases.  They are:
 733 + *
 734 + * regstart    char that must begin a match; '\0' if none obvious
 735 + * reganch     is the match anchored (at beginning-of-line only)?
 736 + * regmust     string (pointer into program) that match must include, or NULL
 737 + * regmlen     length of regmust string
 738 + *
 739 + * Regstart and reganch permit very fast decisions on suitable starting points
 740 + * for a match, cutting down the work a lot.  Regmust permits fast rejection
 741 + * of lines that cannot possibly match.  The regmust tests are costly enough
 742 + * that regcomp() supplies a regmust only if the r.e. contains something
 743 + * potentially expensive (at present, the only such thing detected is * or +
 744 + * at the start of the r.e., which can involve a lot of backup).  Regmlen is
 745 + * supplied because the test in regexec() needs it and regcomp() is computing
 746 + * it anyway.
 747 + */
 748 +
 749 +/*
 750 + * Structure for regexp "program".  This is essentially a linear encoding
 751 + * of a nondeterministic finite-state machine (aka syntax charts or
 752 + * "railroad normal form" in parsing technology).  Each node is an opcode
 753 + * plus a "next" pointer, possibly plus an operand.  "Next" pointers of
 754 + * all nodes except BRANCH implement concatenation; a "next" pointer with
 755 + * a BRANCH on both ends of it is connecting two alternatives.  (Here we
 756 + * have one of the subtle syntax dependencies:  an individual BRANCH (as
 757 + * opposed to a collection of them) is never concatenated with anything
 758 + * because of operator precedence.)  The operand of some types of node is
 759 + * a literal string; for others, it is a node leading into a sub-FSM.  In
 760 + * particular, the operand of a BRANCH node is the first node of the branch.
 761 + * (NB this is *not* a tree structure:  the tail of the branch connects
 762 + * to the thing following the set of BRANCHes.)  The opcodes are:
 763 + */
 764 +
 765 +/* definition  number  opnd?   meaning */
 766 +#define        END     0       /* no   End of program. */
 767 +#define        BOL     1       /* no   Match "" at beginning of line. */
 768 +#define        EOL     2       /* no   Match "" at end of line. */
 769 +#define        ANY     3       /* no   Match any one character. */
 770 +#define        ANYOF   4       /* str  Match any character in this string. */
 771 +#define        ANYBUT  5       /* str  Match any character not in this string. */
 772 +#define        BRANCH  6       /* node Match this alternative, or the next... */
 773 +#define        BACK    7       /* no   Match "", "next" ptr points backward. */
 774 +#define        EXACTLY 8       /* str  Match this string. */
 775 +#define        NOTHING 9       /* no   Match empty string. */
 776 +#define        STAR    10      /* node Match this (simple) thing 0 or more times. */
 777 +#define        PLUS    11      /* node Match this (simple) thing 1 or more times. */
 778 +#define        OPEN    20      /* no   Mark this point in input as start of #n. */
 779 +                       /*      OPEN+1 is number 1, etc. */
 780 +#define        CLOSE   30      /* no   Analogous to OPEN. */
 781 +
 782 +/*
 783 + * Opcode notes:
 784 + *
 785 + * BRANCH      The set of branches constituting a single choice are hooked
 786 + *             together with their "next" pointers, since precedence prevents
 787 + *             anything being concatenated to any individual branch.  The
 788 + *             "next" pointer of the last BRANCH in a choice points to the
 789 + *             thing following the whole choice.  This is also where the
 790 + *             final "next" pointer of each individual branch points; each
 791 + *             branch starts with the operand node of a BRANCH node.
 792 + *
 793 + * BACK                Normal "next" pointers all implicitly point forward; BACK
 794 + *             exists to make loop structures possible.
 795 + *
 796 + * STAR,PLUS   '?', and complex '*' and '+', are implemented as circular
 797 + *             BRANCH structures using BACK.  Simple cases (one character
 798 + *             per match) are implemented with STAR and PLUS for speed
 799 + *             and to minimize recursive plunges.
 800 + *
 801 + * OPEN,CLOSE  ...are numbered at compile time.
 802 + */
 803 +
 804 +/*
 805 + * A node is one char of opcode followed by two chars of "next" pointer.
 806 + * "Next" pointers are stored as two 8-bit pieces, high order first.  The
 807 + * value is a positive offset from the opcode of the node containing it.
 808 + * An operand, if any, simply follows the node.  (Note that much of the
 809 + * code generation knows about this implicit relationship.)
 810 + *
 811 + * Using two bytes for the "next" pointer is vast overkill for most things,
 812 + * but allows patterns to get big without disasters.
 813 + */
 814 +#define        OP(p)   (*(p))
 815 +#define        NEXT(p) (((*((p)+1)&0377)<<8) + (*((p)+2)&0377))
 816 +#define        OPERAND(p)      ((p) + 3)
 817 +
 818 +/*
 819 + * See regmagic.h for one further detail of program structure.
 820 + */
 821 +
 822 +
 823 +/*
 824 + * Utility definitions.
 825 + */
 826 +#ifndef CHARBITS
 827 +#define        UCHARAT(p)      ((int)*(unsigned char *)(p))
 828 +#else
 829 +#define        UCHARAT(p)      ((int)*(p)&CHARBITS)
 830 +#endif
 831 +
 832 +#define        FAIL(m) { regerror(m); return(NULL); }
 833 +#define        ISMULT(c)       ((c) == '*' || (c) == '+' || (c) == '?')
 834 +#define        META    "^$.[()|?+*\\"
 835 +
 836 +/*
 837 + * Flags to be passed up and down.
 838 + */
 839 +#define        HASWIDTH        01      /* Known never to match null string. */
 840 +#define        SIMPLE          02      /* Simple enough to be STAR/PLUS operand. */
 841 +#define        SPSTART         04      /* Starts with * or +. */
 842 +#define        WORST           0       /* Worst case. */
 843 +
 844 +/*
 845 + * Global work variables for regcomp().
 846 + */
 847 +struct match_globals {
 848 +char *reginput;                /* String-input pointer. */
 849 +char *regbol;          /* Beginning of input, for ^ check. */
 850 +char **regstartp;      /* Pointer to startp array. */
 851 +char **regendp;                /* Ditto for endp. */
 852 +char *regparse;                /* Input-scan pointer. */
 853 +int regnpar;           /* () count. */
 854 +char regdummy;
 855 +char *regcode;         /* Code-emit pointer; &regdummy = don't. */
 856 +long regsize;          /* Code size. */
 857 +};
 858 +
 859 +/*
 860 + * Forward declarations for regcomp()'s friends.
 861 + */
 862 +#ifndef STATIC
 863 +#define        STATIC  static
 864 +#endif
 865 +STATIC char *reg(struct match_globals *g, int paren,int *flagp);
 866 +STATIC char *regbranch(struct match_globals *g, int *flagp);
 867 +STATIC char *regpiece(struct match_globals *g, int *flagp);
 868 +STATIC char *regatom(struct match_globals *g, int *flagp);
 869 +STATIC char *regnode(struct match_globals *g, char op);
 870 +STATIC char *regnext(struct match_globals *g, char *p);
 871 +STATIC void regc(struct match_globals *g, char b);
 872 +STATIC void reginsert(struct match_globals *g, char op, char *opnd);
 873 +STATIC void regtail(struct match_globals *g, char *p, char *val);
 874 +STATIC void regoptail(struct match_globals *g, char *p, char *val);
 875 +
 876 +
 877 +__kernel_size_t my_strcspn(const char *s1,const char *s2)
 878 +{
 879 +        char *scan1;
 880 +        char *scan2;
 881 +        int count;
 882 +
 883 +        count = 0;
 884 +        for (scan1 = (char *)s1; *scan1 != '\0'; scan1++) {
 885 +                for (scan2 = (char *)s2; *scan2 != '\0';)       /* ++ moved down. */
 886 +                        if (*scan1 == *scan2++)
 887 +                                return(count);
 888 +                count++;
 889 +        }
 890 +        return(count);
 891 +}
 892 +
 893 +/*
 894 + - regcomp - compile a regular expression into internal code
 895 + *
 896 + * We can't allocate space until we know how big the compiled form will be,
 897 + * but we can't compile it (and thus know how big it is) until we've got a
 898 + * place to put the code.  So we cheat:  we compile it twice, once with code
 899 + * generation turned off and size counting turned on, and once "for real".
 900 + * This also means that we don't allocate space until we are sure that the
 901 + * thing really will compile successfully, and we never have to move the
 902 + * code and thus invalidate pointers into it.  (Note that it has to be in
 903 + * one piece because free() must be able to free it all.)
 904 + *
 905 + * Beware that the optimization-preparation code in here knows about some
 906 + * of the structure of the compiled regexp.
 907 + */
 908 +regexp *
 909 +regcomp(char *exp,int *patternsize)
 910 +{
 911 +       register regexp *r;
 912 +       register char *scan;
 913 +       register char *longest;
 914 +       register int len;
 915 +       int flags;
 916 +       struct match_globals g;
 917 +
 918 +       /* commented out by ethan
 919 +          extern char *malloc();
 920 +       */
 921 +
 922 +       if (exp == NULL)
 923 +               FAIL("NULL argument");
 924 +
 925 +       /* First pass: determine size, legality. */
 926 +       g.regparse = exp;
 927 +       g.regnpar = 1;
 928 +       g.regsize = 0L;
 929 +       g.regcode = &g.regdummy;
 930 +       regc(&g, MAGIC);
 931 +       if (reg(&g, 0, &flags) == NULL)
 932 +               return(NULL);
 933 +
 934 +       /* Small enough for pointer-storage convention? */
 935 +       if (g.regsize >= 32767L)                /* Probably could be 65535L. */
 936 +               FAIL("regexp too big");
 937 +
 938 +       /* Allocate space. */
 939 +       *patternsize=sizeof(regexp) + (unsigned)g.regsize;
 940 +       r = (regexp *)malloc(sizeof(regexp) + (unsigned)g.regsize);
 941 +       if (r == NULL)
 942 +               FAIL("out of space");
 943 +
 944 +       /* Second pass: emit code. */
 945 +       g.regparse = exp;
 946 +       g.regnpar = 1;
 947 +       g.regcode = r->program;
 948 +       regc(&g, MAGIC);
 949 +       if (reg(&g, 0, &flags) == NULL)
 950 +               return(NULL);
 951 +
 952 +       /* Dig out information for optimizations. */
 953 +       r->regstart = '\0';     /* Worst-case defaults. */
 954 +       r->reganch = 0;
 955 +       r->regmust = NULL;
 956 +       r->regmlen = 0;
 957 +       scan = r->program+1;                    /* First BRANCH. */
 958 +       if (OP(regnext(&g, scan)) == END) {             /* Only one top-level choice. */
 959 +               scan = OPERAND(scan);
 960 +
 961 +               /* Starting-point info. */
 962 +               if (OP(scan) == EXACTLY)
 963 +                       r->regstart = *OPERAND(scan);
 964 +               else if (OP(scan) == BOL)
 965 +                       r->reganch++;
 966 +
 967 +               /*
 968 +                * If there's something expensive in the r.e., find the
 969 +                * longest literal string that must appear and make it the
 970 +                * regmust.  Resolve ties in favor of later strings, since
 971 +                * the regstart check works with the beginning of the r.e.
 972 +                * and avoiding duplication strengthens checking.  Not a
 973 +                * strong reason, but sufficient in the absence of others.
 974 +                */
 975 +               if (flags&SPSTART) {
 976 +                       longest = NULL;
 977 +                       len = 0;
 978 +                       for (; scan != NULL; scan = regnext(&g, scan))
 979 +                               if (OP(scan) == EXACTLY && strlen(OPERAND(scan)) >= len) {
 980 +                                       longest = OPERAND(scan);
 981 +                                       len = strlen(OPERAND(scan));
 982 +                               }
 983 +                       r->regmust = longest;
 984 +                       r->regmlen = len;
 985 +               }
 986 +       }
 987 +
 988 +       return(r);
 989 +}
 990 +
 991 +/*
 992 + - reg - regular expression, i.e. main body or parenthesized thing
 993 + *
 994 + * Caller must absorb opening parenthesis.
 995 + *
 996 + * Combining parenthesis handling with the base level of regular expression
 997 + * is a trifle forced, but the need to tie the tails of the branches to what
 998 + * follows makes it hard to avoid.
 999 + */
1000 +static char *
1001 +reg(struct match_globals *g, int paren, int *flagp /* Parenthesized? */ )
1002 +{
1003 +       register char *ret;
1004 +       register char *br;
1005 +       register char *ender;
1006 +       register int parno = 0; /* 0 makes gcc happy */
1007 +       int flags;
1008 +
1009 +       *flagp = HASWIDTH;      /* Tentatively. */
1010 +
1011 +       /* Make an OPEN node, if parenthesized. */
1012 +       if (paren) {
1013 +               if (g->regnpar >= NSUBEXP)
1014 +                       FAIL("too many ()");
1015 +               parno = g->regnpar;
1016 +               g->regnpar++;
1017 +               ret = regnode(g, OPEN+parno);
1018 +       } else
1019 +               ret = NULL;
1020 +
1021 +       /* Pick up the branches, linking them together. */
1022 +       br = regbranch(g, &flags);
1023 +       if (br == NULL)
1024 +               return(NULL);
1025 +       if (ret != NULL)
1026 +               regtail(g, ret, br);    /* OPEN -> first. */
1027 +       else
1028 +               ret = br;
1029 +       if (!(flags&HASWIDTH))
1030 +               *flagp &= ~HASWIDTH;
1031 +       *flagp |= flags&SPSTART;
1032 +       while (*g->regparse == '|') {
1033 +               g->regparse++;
1034 +               br = regbranch(g, &flags);
1035 +               if (br == NULL)
1036 +                       return(NULL);
1037 +               regtail(g, ret, br);    /* BRANCH -> BRANCH. */
1038 +               if (!(flags&HASWIDTH))
1039 +                       *flagp &= ~HASWIDTH;
1040 +               *flagp |= flags&SPSTART;
1041 +       }
1042 +
1043 +       /* Make a closing node, and hook it on the end. */
1044 +       ender = regnode(g, (paren) ? CLOSE+parno : END);
1045 +       regtail(g, ret, ender);
1046 +
1047 +       /* Hook the tails of the branches to the closing node. */
1048 +       for (br = ret; br != NULL; br = regnext(g, br))
1049 +               regoptail(g, br, ender);
1050 +
1051 +       /* Check for proper termination. */
1052 +       if (paren && *g->regparse++ != ')') {
1053 +               FAIL("unmatched ()");
1054 +       } else if (!paren && *g->regparse != '\0') {
1055 +               if (*g->regparse == ')') {
1056 +                       FAIL("unmatched ()");
1057 +               } else
1058 +                       FAIL("junk on end");    /* "Can't happen". */
1059 +               /* NOTREACHED */
1060 +       }
1061 +
1062 +       return(ret);
1063 +}
1064 +
1065 +/*
1066 + - regbranch - one alternative of an | operator
1067 + *
1068 + * Implements the concatenation operator.
1069 + */
1070 +static char *
1071 +regbranch(struct match_globals *g, int *flagp)
1072 +{
1073 +       register char *ret;
1074 +       register char *chain;
1075 +       register char *latest;
1076 +       int flags;
1077 +
1078 +       *flagp = WORST;         /* Tentatively. */
1079 +
1080 +       ret = regnode(g, BRANCH);
1081 +       chain = NULL;
1082 +       while (*g->regparse != '\0' && *g->regparse != '|' && *g->regparse != ')') {
1083 +               latest = regpiece(g, &flags);
1084 +               if (latest == NULL)
1085 +                       return(NULL);
1086 +               *flagp |= flags&HASWIDTH;
1087 +               if (chain == NULL)      /* First piece. */
1088 +                       *flagp |= flags&SPSTART;
1089 +               else
1090 +                       regtail(g, chain, latest);
1091 +               chain = latest;
1092 +       }
1093 +       if (chain == NULL)      /* Loop ran zero times. */
1094 +               (void) regnode(g, NOTHING);
1095 +
1096 +       return(ret);
1097 +}
1098 +
1099 +/*
1100 + - regpiece - something followed by possible [*+?]
1101 + *
1102 + * Note that the branching code sequences used for ? and the general cases
1103 + * of * and + are somewhat optimized:  they use the same NOTHING node as
1104 + * both the endmarker for their branch list and the body of the last branch.
1105 + * It might seem that this node could be dispensed with entirely, but the
1106 + * endmarker role is not redundant.
1107 + */
1108 +static char *
1109 +regpiece(struct match_globals *g, int *flagp)
1110 +{
1111 +       register char *ret;
1112 +       register char op;
1113 +       register char *next;
1114 +       int flags;
1115 +
1116 +       ret = regatom(g, &flags);
1117 +       if (ret == NULL)
1118 +               return(NULL);
1119 +
1120 +       op = *g->regparse;
1121 +       if (!ISMULT(op)) {
1122 +               *flagp = flags;
1123 +               return(ret);
1124 +       }
1125 +
1126 +       if (!(flags&HASWIDTH) && op != '?')
1127 +               FAIL("*+ operand could be empty");
1128 +       *flagp = (op != '+') ? (WORST|SPSTART) : (WORST|HASWIDTH);
1129 +
1130 +       if (op == '*' && (flags&SIMPLE))
1131 +               reginsert(g, STAR, ret);
1132 +       else if (op == '*') {
1133 +               /* Emit x* as (x&|), where & means "self". */
1134 +               reginsert(g, BRANCH, ret);                      /* Either x */
1135 +               regoptail(g, ret, regnode(g, BACK));            /* and loop */
1136 +               regoptail(g, ret, ret);                 /* back */
1137 +               regtail(g, ret, regnode(g, BRANCH));            /* or */
1138 +               regtail(g, ret, regnode(g, NOTHING));           /* null. */
1139 +       } else if (op == '+' && (flags&SIMPLE))
1140 +               reginsert(g, PLUS, ret);
1141 +       else if (op == '+') {
1142 +               /* Emit x+ as x(&|), where & means "self". */
1143 +               next = regnode(g, BRANCH);                      /* Either */
1144 +               regtail(g, ret, next);
1145 +               regtail(g, regnode(g, BACK), ret);              /* loop back */
1146 +               regtail(g, next, regnode(g, BRANCH));           /* or */
1147 +               regtail(g, ret, regnode(g, NOTHING));           /* null. */
1148 +       } else if (op == '?') {
1149 +               /* Emit x? as (x|) */
1150 +               reginsert(g, BRANCH, ret);                      /* Either x */
1151 +               regtail(g, ret, regnode(g, BRANCH));            /* or */
1152 +               next = regnode(g, NOTHING);             /* null. */
1153 +               regtail(g, ret, next);
1154 +               regoptail(g, ret, next);
1155 +       }
1156 +       g->regparse++;
1157 +       if (ISMULT(*g->regparse))
1158 +               FAIL("nested *?+");
1159 +
1160 +       return(ret);
1161 +}
1162 +
1163 +/*
1164 + - regatom - the lowest level
1165 + *
1166 + * Optimization:  gobbles an entire sequence of ordinary characters so that
1167 + * it can turn them into a single node, which is smaller to store and
1168 + * faster to run.  Backslashed characters are exceptions, each becoming a
1169 + * separate node; the code is simpler that way and it's not worth fixing.
1170 + */
1171 +static char *
1172 +regatom(struct match_globals *g, int *flagp)
1173 +{
1174 +       register char *ret;
1175 +       int flags;
1176 +
1177 +       *flagp = WORST;         /* Tentatively. */
1178 +
1179 +       switch (*g->regparse++) {
1180 +       case '^':
1181 +               ret = regnode(g, BOL);
1182 +               break;
1183 +       case '$':
1184 +               ret = regnode(g, EOL);
1185 +               break;
1186 +       case '.':
1187 +               ret = regnode(g, ANY);
1188 +               *flagp |= HASWIDTH|SIMPLE;
1189 +               break;
1190 +       case '[': {
1191 +                       register int class;
1192 +                       register int classend;
1193 +
1194 +                       if (*g->regparse == '^') {      /* Complement of range. */
1195 +                               ret = regnode(g, ANYBUT);
1196 +                               g->regparse++;
1197 +                       } else
1198 +                               ret = regnode(g, ANYOF);
1199 +                       if (*g->regparse == ']' || *g->regparse == '-')
1200 +                               regc(g, *g->regparse++);
1201 +                       while (*g->regparse != '\0' && *g->regparse != ']') {
1202 +                               if (*g->regparse == '-') {
1203 +                                       g->regparse++;
1204 +                                       if (*g->regparse == ']' || *g->regparse == '\0')
1205 +                                               regc(g, '-');
1206 +                                       else {
1207 +                                               class = UCHARAT(g->regparse-2)+1;
1208 +                                               classend = UCHARAT(g->regparse);
1209 +                                               if (class > classend+1)
1210 +                                                       FAIL("invalid [] range");
1211 +                                               for (; class <= classend; class++)
1212 +                                                       regc(g, class);
1213 +                                               g->regparse++;
1214 +                                       }
1215 +                               } else
1216 +                                       regc(g, *g->regparse++);
1217 +                       }
1218 +                       regc(g, '\0');
1219 +                       if (*g->regparse != ']')
1220 +                               FAIL("unmatched []");
1221 +                       g->regparse++;
1222 +                       *flagp |= HASWIDTH|SIMPLE;
1223 +               }
1224 +               break;
1225 +       case '(':
1226 +               ret = reg(g, 1, &flags);
1227 +               if (ret == NULL)
1228 +                       return(NULL);
1229 +               *flagp |= flags&(HASWIDTH|SPSTART);
1230 +               break;
1231 +       case '\0':
1232 +       case '|':
1233 +       case ')':
1234 +               FAIL("internal urp");   /* Supposed to be caught earlier. */
1235 +               break;
1236 +       case '?':
1237 +       case '+':
1238 +       case '*':
1239 +               FAIL("?+* follows nothing");
1240 +               break;
1241 +       case '\\':
1242 +               if (*g->regparse == '\0')
1243 +                       FAIL("trailing \\");
1244 +               ret = regnode(g, EXACTLY);
1245 +               regc(g, *g->regparse++);
1246 +               regc(g, '\0');
1247 +               *flagp |= HASWIDTH|SIMPLE;
1248 +               break;
1249 +       default: {
1250 +                       register int len;
1251 +                       register char ender;
1252 +
1253 +                       g->regparse--;
1254 +                       len = my_strcspn((const char *)g->regparse, (const char *)META);
1255 +                       if (len <= 0)
1256 +                               FAIL("internal disaster");
1257 +                       ender = *(g->regparse+len);
1258 +                       if (len > 1 && ISMULT(ender))
1259 +                               len--;          /* Back off clear of ?+* operand. */
1260 +                       *flagp |= HASWIDTH;
1261 +                       if (len == 1)
1262 +                               *flagp |= SIMPLE;
1263 +                       ret = regnode(g, EXACTLY);
1264 +                       while (len > 0) {
1265 +                               regc(g, *g->regparse++);
1266 +                               len--;
1267 +                       }
1268 +                       regc(g, '\0');
1269 +               }
1270 +               break;
1271 +       }
1272 +
1273 +       return(ret);
1274 +}
1275 +
1276 +/*
1277 + - regnode - emit a node
1278 + */
1279 +static char *                  /* Location. */
1280 +regnode(struct match_globals *g, char op)
1281 +{
1282 +       register char *ret;
1283 +       register char *ptr;
1284 +
1285 +       ret = g->regcode;
1286 +       if (ret == &g->regdummy) {
1287 +               g->regsize += 3;
1288 +               return(ret);
1289 +       }
1290 +
1291 +       ptr = ret;
1292 +       *ptr++ = op;
1293 +       *ptr++ = '\0';          /* Null "next" pointer. */
1294 +       *ptr++ = '\0';
1295 +       g->regcode = ptr;
1296 +
1297 +       return(ret);
1298 +}
1299 +
1300 +/*
1301 + - regc - emit (if appropriate) a byte of code
1302 + */
1303 +static void
1304 +regc(struct match_globals *g, char b)
1305 +{
1306 +       if (g->regcode != &g->regdummy)
1307 +               *g->regcode++ = b;
1308 +       else
1309 +               g->regsize++;
1310 +}
1311 +
1312 +/*
1313 + - reginsert - insert an operator in front of already-emitted operand
1314 + *
1315 + * Means relocating the operand.
1316 + */
1317 +static void
1318 +reginsert(struct match_globals *g, char op, char* opnd)
1319 +{
1320 +       register char *src;
1321 +       register char *dst;
1322 +       register char *place;
1323 +
1324 +       if (g->regcode == &g->regdummy) {
1325 +               g->regsize += 3;
1326 +               return;
1327 +       }
1328 +
1329 +       src = g->regcode;
1330 +       g->regcode += 3;
1331 +       dst = g->regcode;
1332 +       while (src > opnd)
1333 +               *--dst = *--src;
1334 +
1335 +       place = opnd;           /* Op node, where operand used to be. */
1336 +       *place++ = op;
1337 +       *place++ = '\0';
1338 +       *place++ = '\0';
1339 +}
1340 +
1341 +/*
1342 + - regtail - set the next-pointer at the end of a node chain
1343 + */
1344 +static void
1345 +regtail(struct match_globals *g, char *p, char *val)
1346 +{
1347 +       register char *scan;
1348 +       register char *temp;
1349 +       register int offset;
1350 +
1351 +       if (p == &g->regdummy)
1352 +               return;
1353 +
1354 +       /* Find last node. */
1355 +       scan = p;
1356 +       for (;;) {
1357 +               temp = regnext(g, scan);
1358 +               if (temp == NULL)
1359 +                       break;
1360 +               scan = temp;
1361 +       }
1362 +
1363 +       if (OP(scan) == BACK)
1364 +               offset = scan - val;
1365 +       else
1366 +               offset = val - scan;
1367 +       *(scan+1) = (offset>>8)&0377;
1368 +       *(scan+2) = offset&0377;
1369 +}
1370 +
1371 +/*
1372 + - regoptail - regtail on operand of first argument; nop if operandless
1373 + */
1374 +static void
1375 +regoptail(struct match_globals *g, char *p, char *val)
1376 +{
1377 +       /* "Operandless" and "op != BRANCH" are synonymous in practice. */
1378 +       if (p == NULL || p == &g->regdummy || OP(p) != BRANCH)
1379 +               return;
1380 +       regtail(g, OPERAND(p), val);
1381 +}
1382 +
1383 +/*
1384 + * regexec and friends
1385 + */
1386 +
1387 +
1388 +/*
1389 + * Forwards.
1390 + */
1391 +STATIC int regtry(struct match_globals *g, regexp *prog, char *string);
1392 +STATIC int regmatch(struct match_globals *g, char *prog);
1393 +STATIC int regrepeat(struct match_globals *g, char *p);
1394 +
1395 +#ifdef DEBUG
1396 +int regnarrate = 0;
1397 +void regdump();
1398 +STATIC char *regprop(char *op);
1399 +#endif
1400 +
1401 +/*
1402 + - regexec - match a regexp against a string
1403 + */
1404 +int
1405 +regexec(regexp *prog, char *string)
1406 +{
1407 +       register char *s;
1408 +       struct match_globals g;
1409 +
1410 +       /* Be paranoid... */
1411 +       if (prog == NULL || string == NULL) {
1412 +               printk("<3>Regexp: NULL parameter\n");
1413 +               return(0);
1414 +       }
1415 +
1416 +       /* Check validity of program. */
1417 +       if (UCHARAT(prog->program) != MAGIC) {
1418 +               printk("<3>Regexp: corrupted program\n");
1419 +               return(0);
1420 +       }
1421 +
1422 +       /* If there is a "must appear" string, look for it. */
1423 +       if (prog->regmust != NULL) {
1424 +               s = string;
1425 +               while ((s = strchr(s, prog->regmust[0])) != NULL) {
1426 +                       if (strncmp(s, prog->regmust, prog->regmlen) == 0)
1427 +                               break;  /* Found it. */
1428 +                       s++;
1429 +               }
1430 +               if (s == NULL)  /* Not present. */
1431 +                       return(0);
1432 +       }
1433 +
1434 +       /* Mark beginning of line for ^ . */
1435 +       g.regbol = string;
1436 +
1437 +       /* Simplest case:  anchored match need be tried only once. */
1438 +       if (prog->reganch)
1439 +               return(regtry(&g, prog, string));
1440 +
1441 +       /* Messy cases:  unanchored match. */
1442 +       s = string;
1443 +       if (prog->regstart != '\0')
1444 +               /* We know what char it must start with. */
1445 +               while ((s = strchr(s, prog->regstart)) != NULL) {
1446 +                       if (regtry(&g, prog, s))
1447 +                               return(1);
1448 +                       s++;
1449 +               }
1450 +       else
1451 +               /* We don't -- general case. */
1452 +               do {
1453 +                       if (regtry(&g, prog, s))
1454 +                               return(1);
1455 +               } while (*s++ != '\0');
1456 +
1457 +       /* Failure. */
1458 +       return(0);
1459 +}
1460 +
1461 +/*
1462 + - regtry - try match at specific point
1463 + */
1464 +static int                     /* 0 failure, 1 success */
1465 +regtry(struct match_globals *g, regexp *prog, char *string)
1466 +{
1467 +       register int i;
1468 +       register char **sp;
1469 +       register char **ep;
1470 +
1471 +       g->reginput = string;
1472 +       g->regstartp = prog->startp;
1473 +       g->regendp = prog->endp;
1474 +
1475 +       sp = prog->startp;
1476 +       ep = prog->endp;
1477 +       for (i = NSUBEXP; i > 0; i--) {
1478 +               *sp++ = NULL;
1479 +               *ep++ = NULL;
1480 +       }
1481 +       if (regmatch(g, prog->program + 1)) {
1482 +               prog->startp[0] = string;
1483 +               prog->endp[0] = g->reginput;
1484 +               return(1);
1485 +       } else
1486 +               return(0);
1487 +}
1488 +
1489 +/*
1490 + - regmatch - main matching routine
1491 + *
1492 + * Conceptually the strategy is simple:  check to see whether the current
1493 + * node matches, call self recursively to see whether the rest matches,
1494 + * and then act accordingly.  In practice we make some effort to avoid
1495 + * recursion, in particular by going through "ordinary" nodes (that don't
1496 + * need to know whether the rest of the match failed) by a loop instead of
1497 + * by recursion.
1498 + */
1499 +static int                     /* 0 failure, 1 success */
1500 +regmatch(struct match_globals *g, char *prog)
1501 +{
1502 +       register char *scan = prog; /* Current node. */
1503 +       char *next;                 /* Next node. */
1504 +
1505 +#ifdef DEBUG
1506 +       if (scan != NULL && regnarrate)
1507 +               fprintf(stderr, "%s(\n", regprop(scan));
1508 +#endif
1509 +       while (scan != NULL) {
1510 +#ifdef DEBUG
1511 +               if (regnarrate)
1512 +                       fprintf(stderr, "%s...\n", regprop(scan));
1513 +#endif
1514 +               next = regnext(g, scan);
1515 +
1516 +               switch (OP(scan)) {
1517 +               case BOL:
1518 +                       if (g->reginput != g->regbol)
1519 +                               return(0);
1520 +                       break;
1521 +               case EOL:
1522 +                       if (*g->reginput != '\0')
1523 +                               return(0);
1524 +                       break;
1525 +               case ANY:
1526 +                       if (*g->reginput == '\0')
1527 +                               return(0);
1528 +                       g->reginput++;
1529 +                       break;
1530 +               case EXACTLY: {
1531 +                               register int len;
1532 +                               register char *opnd;
1533 +
1534 +                               opnd = OPERAND(scan);
1535 +                               /* Inline the first character, for speed. */
1536 +                               if (*opnd != *g->reginput)
1537 +                                       return(0);
1538 +                               len = strlen(opnd);
1539 +                               if (len > 1 && strncmp(opnd, g->reginput, len) != 0)
1540 +                                       return(0);
1541 +                               g->reginput += len;
1542 +                       }
1543 +                       break;
1544 +               case ANYOF:
1545 +                       if (*g->reginput == '\0' || strchr(OPERAND(scan), *g->reginput) == NULL)
1546 +                               return(0);
1547 +                       g->reginput++;
1548 +                       break;
1549 +               case ANYBUT:
1550 +                       if (*g->reginput == '\0' || strchr(OPERAND(scan), *g->reginput) != NULL)
1551 +                               return(0);
1552 +                       g->reginput++;
1553 +                       break;
1554 +               case NOTHING:
1555 +               case BACK:
1556 +                       break;
1557 +               case OPEN+1:
1558 +               case OPEN+2:
1559 +               case OPEN+3:
1560 +               case OPEN+4:
1561 +               case OPEN+5:
1562 +               case OPEN+6:
1563 +               case OPEN+7:
1564 +               case OPEN+8:
1565 +               case OPEN+9: {
1566 +                               register int no;
1567 +                               register char *save;
1568 +
1569 +                               no = OP(scan) - OPEN;
1570 +                               save = g->reginput;
1571 +
1572 +                               if (regmatch(g, next)) {
1573 +                                       /*
1574 +                                        * Don't set startp if some later
1575 +                                        * invocation of the same parentheses
1576 +                                        * already has.
1577 +                                        */
1578 +                                       if (g->regstartp[no] == NULL)
1579 +                                               g->regstartp[no] = save;
1580 +                                       return(1);
1581 +                               } else
1582 +                                       return(0);
1583 +                       }
1584 +                       break;
1585 +               case CLOSE+1:
1586 +               case CLOSE+2:
1587 +               case CLOSE+3:
1588 +               case CLOSE+4:
1589 +               case CLOSE+5:
1590 +               case CLOSE+6:
1591 +               case CLOSE+7:
1592 +               case CLOSE+8:
1593 +               case CLOSE+9:
1594 +                       {
1595 +                               register int no;
1596 +                               register char *save;
1597 +
1598 +                               no = OP(scan) - CLOSE;
1599 +                               save = g->reginput;
1600 +
1601 +                               if (regmatch(g, next)) {
1602 +                                       /*
1603 +                                        * Don't set endp if some later
1604 +                                        * invocation of the same parentheses
1605 +                                        * already has.
1606 +                                        */
1607 +                                       if (g->regendp[no] == NULL)
1608 +                                               g->regendp[no] = save;
1609 +                                       return(1);
1610 +                               } else
1611 +                                       return(0);
1612 +                       }
1613 +                       break;
1614 +               case BRANCH: {
1615 +                               register char *save;
1616 +
1617 +                               if (OP(next) != BRANCH)         /* No choice. */
1618 +                                       next = OPERAND(scan);   /* Avoid recursion. */
1619 +                               else {
1620 +                                       do {
1621 +                                               save = g->reginput;
1622 +                                               if (regmatch(g, OPERAND(scan)))
1623 +                                                       return(1);
1624 +                                               g->reginput = save;
1625 +                                               scan = regnext(g, scan);
1626 +                                       } while (scan != NULL && OP(scan) == BRANCH);
1627 +                                       return(0);
1628 +                                       /* NOTREACHED */
1629 +                               }
1630 +                       }
1631 +                       break;
1632 +               case STAR:
1633 +               case PLUS: {
1634 +                               register char nextch;
1635 +                               register int no;
1636 +                               register char *save;
1637 +                               register int min;
1638 +
1639 +                               /*
1640 +                                * Lookahead to avoid useless match attempts
1641 +                                * when we know what character comes next.
1642 +                                */
1643 +                               nextch = '\0';
1644 +                               if (OP(next) == EXACTLY)
1645 +                                       nextch = *OPERAND(next);
1646 +                               min = (OP(scan) == STAR) ? 0 : 1;
1647 +                               save = g->reginput;
1648 +                               no = regrepeat(g, OPERAND(scan));
1649 +                               while (no >= min) {
1650 +                                       /* If it could work, try it. */
1651 +                                       if (nextch == '\0' || *g->reginput == nextch)
1652 +                                               if (regmatch(g, next))
1653 +                                                       return(1);
1654 +                                       /* Couldn't or didn't -- back up. */
1655 +                                       no--;
1656 +                                       g->reginput = save + no;
1657 +                               }
1658 +                               return(0);
1659 +                       }
1660 +                       break;
1661 +               case END:
1662 +                       return(1);      /* Success! */
1663 +                       break;
1664 +               default:
1665 +                       printk("<3>Regexp: memory corruption\n");
1666 +                       return(0);
1667 +                       break;
1668 +               }
1669 +
1670 +               scan = next;
1671 +       }
1672 +
1673 +       /*
1674 +        * We get here only if there's trouble -- normally "case END" is
1675 +        * the terminating point.
1676 +        */
1677 +       printk("<3>Regexp: corrupted pointers\n");
1678 +       return(0);
1679 +}
1680 +
1681 +/*
1682 + - regrepeat - repeatedly match something simple, report how many
1683 + */
1684 +static int
1685 +regrepeat(struct match_globals *g, char *p)
1686 +{
1687 +       register int count = 0;
1688 +       register char *scan;
1689 +       register char *opnd;
1690 +
1691 +       scan = g->reginput;
1692 +       opnd = OPERAND(p);
1693 +       switch (OP(p)) {
1694 +       case ANY:
1695 +               count = strlen(scan);
1696 +               scan += count;
1697 +               break;
1698 +       case EXACTLY:
1699 +               while (*opnd == *scan) {
1700 +                       count++;
1701 +                       scan++;
1702 +               }
1703 +               break;
1704 +       case ANYOF:
1705 +               while (*scan != '\0' && strchr(opnd, *scan) != NULL) {
1706 +                       count++;
1707 +                       scan++;
1708 +               }
1709 +               break;
1710 +       case ANYBUT:
1711 +               while (*scan != '\0' && strchr(opnd, *scan) == NULL) {
1712 +                       count++;
1713 +                       scan++;
1714 +               }
1715 +               break;
1716 +       default:                /* Oh dear.  Called inappropriately. */
1717 +               printk("<3>Regexp: internal foulup\n");
1718 +               count = 0;      /* Best compromise. */
1719 +               break;
1720 +       }
1721 +       g->reginput = scan;
1722 +
1723 +       return(count);
1724 +}
1725 +
1726 +/*
1727 + - regnext - dig the "next" pointer out of a node
1728 + */
1729 +static char*
1730 +regnext(struct match_globals *g, char *p)
1731 +{
1732 +       register int offset;
1733 +
1734 +       if (p == &g->regdummy)
1735 +               return(NULL);
1736 +
1737 +       offset = NEXT(p);
1738 +       if (offset == 0)
1739 +               return(NULL);
1740 +
1741 +       if (OP(p) == BACK)
1742 +               return(p-offset);
1743 +       else
1744 +               return(p+offset);
1745 +}
1746 +
1747 +#ifdef DEBUG
1748 +
1749 +STATIC char *regprop();
1750 +
1751 +/*
1752 + - regdump - dump a regexp onto stdout in vaguely comprehensible form
1753 + */
1754 +void
1755 +regdump(regexp *r)
1756 +{
1757 +       register char *s;
1758 +       register char op = EXACTLY;     /* Arbitrary non-END op. */
1759 +       register char *next;
1760 +       /* extern char *strchr(); */
1761 +
1762 +
1763 +       s = r->program + 1;
1764 +       while (op != END) {     /* While that wasn't END last time... */
1765 +               op = OP(s);
1766 +               printf("%2d%s", s-r->program, regprop(s));      /* Where, what. */
1767 +               next = regnext(s);
1768 +               if (next == NULL)               /* Next ptr. */
1769 +                       printf("(0)");
1770 +               else
1771 +                       printf("(%d)", (s-r->program)+(next-s));
1772 +               s += 3;
1773 +               if (op == ANYOF || op == ANYBUT || op == EXACTLY) {
1774 +                       /* Literal string, where present. */
1775 +                       while (*s != '\0') {
1776 +                               putchar(*s);
1777 +                               s++;
1778 +                       }
1779 +                       s++;
1780 +               }
1781 +               putchar('\n');
1782 +       }
1783 +
1784 +       /* Header fields of interest. */
1785 +       if (r->regstart != '\0')
1786 +               printf("start `%c' ", r->regstart);
1787 +       if (r->reganch)
1788 +               printf("anchored ");
1789 +       if (r->regmust != NULL)
1790 +               printf("must have \"%s\"", r->regmust);
1791 +       printf("\n");
1792 +}
1793 +
1794 +/*
1795 + - regprop - printable representation of opcode
1796 + */
1797 +static char *
1798 +regprop(char *op)
1799 +{
1800 +#define BUFLEN 50
1801 +       register char *p;
1802 +       static char buf[BUFLEN];
1803 +
1804 +       strcpy(buf, ":");
1805 +
1806 +       switch (OP(op)) {
1807 +       case BOL:
1808 +               p = "BOL";
1809 +               break;
1810 +       case EOL:
1811 +               p = "EOL";
1812 +               break;
1813 +       case ANY:
1814 +               p = "ANY";
1815 +               break;
1816 +       case ANYOF:
1817 +               p = "ANYOF";
1818 +               break;
1819 +       case ANYBUT:
1820 +               p = "ANYBUT";
1821 +               break;
1822 +       case BRANCH:
1823 +               p = "BRANCH";
1824 +               break;
1825 +       case EXACTLY:
1826 +               p = "EXACTLY";
1827 +               break;
1828 +       case NOTHING:
1829 +               p = "NOTHING";
1830 +               break;
1831 +       case BACK:
1832 +               p = "BACK";
1833 +               break;
1834 +       case END:
1835 +               p = "END";
1836 +               break;
1837 +       case OPEN+1:
1838 +       case OPEN+2:
1839 +       case OPEN+3:
1840 +       case OPEN+4:
1841 +       case OPEN+5:
1842 +       case OPEN+6:
1843 +       case OPEN+7:
1844 +       case OPEN+8:
1845 +       case OPEN+9:
1846 +               snprintf(buf+strlen(buf),BUFLEN-strlen(buf), "OPEN%d", OP(op)-OPEN);
1847 +               p = NULL;
1848 +               break;
1849 +       case CLOSE+1:
1850 +       case CLOSE+2:
1851 +       case CLOSE+3:
1852 +       case CLOSE+4:
1853 +       case CLOSE+5:
1854 +       case CLOSE+6:
1855 +       case CLOSE+7:
1856 +       case CLOSE+8:
1857 +       case CLOSE+9:
1858 +               snprintf(buf+strlen(buf),BUFLEN-strlen(buf), "CLOSE%d", OP(op)-CLOSE);
1859 +               p = NULL;
1860 +               break;
1861 +       case STAR:
1862 +               p = "STAR";
1863 +               break;
1864 +       case PLUS:
1865 +               p = "PLUS";
1866 +               break;
1867 +       default:
1868 +               printk("<3>Regexp: corrupted opcode\n");
1869 +               break;
1870 +       }
1871 +       if (p != NULL)
1872 +               strncat(buf, p, BUFLEN-strlen(buf));
1873 +       return(buf);
1874 +}
1875 +#endif
1876 +
1877 +
1878 --- /dev/null
1879 +++ b/net/netfilter/regexp/regexp.h
1880 @@ -0,0 +1,41 @@
1881 +/*
1882 + * Definitions etc. for regexp(3) routines.
1883 + *
1884 + * Caveat:  this is V8 regexp(3) [actually, a reimplementation thereof],
1885 + * not the System V one.
1886 + */
1887 +
1888 +#ifndef REGEXP_H
1889 +#define REGEXP_H
1890 +
1891 +
1892 +/*
1893 +http://www.opensource.apple.com/darwinsource/10.3/expect-1/expect/expect.h ,
1894 +which contains a version of this library, says:
1895 +
1896 + *
1897 + * NSUBEXP must be at least 10, and no greater than 117 or the parser
1898 + * will not work properly.
1899 + *
1900 +
1901 +However, it looks rather like this library is limited to 10.  If you think
1902 +otherwise, let us know.
1903 +*/
1904 +
1905 +#define NSUBEXP  10
1906 +typedef struct regexp {
1907 +       char *startp[NSUBEXP];
1908 +       char *endp[NSUBEXP];
1909 +       char regstart;          /* Internal use only. */
1910 +       char reganch;           /* Internal use only. */
1911 +       char *regmust;          /* Internal use only. */
1912 +       int regmlen;            /* Internal use only. */
1913 +       char program[1];        /* Unwarranted chumminess with compiler. */
1914 +} regexp;
1915 +
1916 +regexp * regcomp(char *exp, int *patternsize);
1917 +int regexec(regexp *prog, char *string);
1918 +void regsub(regexp *prog, char *source, char *dest);
1919 +void regerror(char *s);
1920 +
1921 +#endif
1922 --- /dev/null
1923 +++ b/net/netfilter/regexp/regmagic.h
1924 @@ -0,0 +1,5 @@
1925 +/*
1926 + * The first byte of the regexp internal "program" is actually this magic
1927 + * number; the start node begins in the second byte.
1928 + */
1929 +#define        MAGIC   0234
1930 --- /dev/null
1931 +++ b/net/netfilter/regexp/regsub.c
1932 @@ -0,0 +1,95 @@
1933 +/*
1934 + * regsub
1935 + * @(#)regsub.c        1.3 of 2 April 86
1936 + *
1937 + *     Copyright (c) 1986 by University of Toronto.
1938 + *     Written by Henry Spencer.  Not derived from licensed software.
1939 + *
1940 + *     Permission is granted to anyone to use this software for any
1941 + *     purpose on any computer system, and to redistribute it freely,
1942 + *     subject to the following restrictions:
1943 + *
1944 + *     1. The author is not responsible for the consequences of use of
1945 + *             this software, no matter how awful, even if they arise
1946 + *             from defects in it.
1947 + *
1948 + *     2. The origin of this software must not be misrepresented, either
1949 + *             by explicit claim or by omission.
1950 + *
1951 + *     3. Altered versions must be plainly marked as such, and must not
1952 + *             be misrepresented as being the original software.
1953 + *
1954 + *
1955 + * This code was modified by Ethan Sommer to work within the kernel
1956 + * (it now uses kmalloc etc..)
1957 + *
1958 + */
1959 +#include "regexp.h"
1960 +#include "regmagic.h"
1961 +#include <linux/string.h>
1962 +
1963 +
1964 +#ifndef CHARBITS
1965 +#define        UCHARAT(p)      ((int)*(unsigned char *)(p))
1966 +#else
1967 +#define        UCHARAT(p)      ((int)*(p)&CHARBITS)
1968 +#endif
1969 +
1970 +#if 0
1971 +//void regerror(char * s)
1972 +//{
1973 +//        printk("regexp(3): %s", s);
1974 +//        /* NOTREACHED */
1975 +//}
1976 +#endif
1977 +
1978 +/*
1979 + - regsub - perform substitutions after a regexp match
1980 + */
1981 +void
1982 +regsub(regexp * prog, char * source, char * dest)
1983 +{
1984 +       register char *src;
1985 +       register char *dst;
1986 +       register char c;
1987 +       register int no;
1988 +       register int len;
1989 +
1990 +       /* Not necessary and gcc doesn't like it -MLS */
1991 +       /*extern char *strncpy();*/
1992 +
1993 +       if (prog == NULL || source == NULL || dest == NULL) {
1994 +               regerror("NULL parm to regsub");
1995 +               return;
1996 +       }
1997 +       if (UCHARAT(prog->program) != MAGIC) {
1998 +               regerror("damaged regexp fed to regsub");
1999 +               return;
2000 +       }
2001 +
2002 +       src = source;
2003 +       dst = dest;
2004 +       while ((c = *src++) != '\0') {
2005 +               if (c == '&')
2006 +                       no = 0;
2007 +               else if (c == '\\' && '0' <= *src && *src <= '9')
2008 +                       no = *src++ - '0';
2009 +               else
2010 +                       no = -1;
2011 +
2012 +               if (no < 0) {   /* Ordinary character. */
2013 +                       if (c == '\\' && (*src == '\\' || *src == '&'))
2014 +                               c = *src++;
2015 +                       *dst++ = c;
2016 +               } else if (prog->startp[no] != NULL && prog->endp[no] != NULL) {
2017 +                       len = prog->endp[no] - prog->startp[no];
2018 +                       (void) strncpy(dst, prog->startp[no], len);
2019 +                       dst += len;
2020 +                       if (len != 0 && *(dst-1) == '\0') {     /* strncpy hit NUL. */
2021 +                               regerror("damaged match string");
2022 +                               return;
2023 +                       }
2024 +               }
2025 +       }
2026 +       *dst++ = '\0';
2027 +}
2028 --- a/net/netfilter/nf_conntrack_core.c
2029 +++ b/net/netfilter/nf_conntrack_core.c
2030 @@ -208,6 +208,14 @@
2031          * too. */
2032         nf_ct_remove_expectations(ct);
2033
2034 +       #if defined(CONFIG_NETFILTER_XT_MATCH_LAYER7) || defined(CONFIG_NETFILTER_XT_MATCH_LAYER7_MODULE)
2035 +       if(ct->layer7.app_proto)
2036 +               kfree(ct->layer7.app_proto);
2037 +       if(ct->layer7.app_data)
2038 +       kfree(ct->layer7.app_data);
2039 +       #endif
2040 +
2041 +
2042         /* We overload first tuple to link into unconfirmed list. */
2043         if (!nf_ct_is_confirmed(ct)) {
2044                 BUG_ON(hlist_unhashed(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnode));
2045 --- a/net/netfilter/nf_conntrack_standalone.c
2046 +++ b/net/netfilter/nf_conntrack_standalone.c
2047 @@ -181,7 +181,12 @@
2048                 return -ENOSPC;
2049  #endif
2050
2051 -       if (seq_printf(s, "use=%u\n", atomic_read(&ct->ct_general.use)))
2052 +#if defined(CONFIG_NETFILTER_XT_MATCH_LAYER7) || defined(CONFIG_NETFILTER_XT_MATCH_LAYER7_MODULE)
2053 +       if(ct->layer7.app_proto)
2054 +               if(seq_printf(s, "l7proto=%s ", ct->layer7.app_proto))
2055 +                       return -ENOSPC;
2056 +#endif
2057 +       if (seq_printf(s, "asdfuse=%u\n", atomic_read(&ct->ct_general.use)))
2058                 return -ENOSPC;
2059
2060         return 0;
2061 --- a/include/net/netfilter/nf_conntrack.h
2062 +++ b/include/net/netfilter/nf_conntrack.h
2063 @@ -124,6 +124,22 @@
2064         u_int32_t secmark;
2065  #endif
2066
2067 +#if defined(CONFIG_NETFILTER_XT_MATCH_LAYER7) || \
2068 +    defined(CONFIG_NETFILTER_XT_MATCH_LAYER7_MODULE)
2069 +       struct {
2070 +               /*
2071 +                * e.g. "http". NULL before decision. "unknown" after decision
2072 +                * if no match.
2073 +                */
2074 +               char *app_proto;
2075 +               /*
2076 +                * application layer data so far. NULL after match decision.
2077 +                */
2078 +               char *app_data;
2079 +               unsigned int app_data_len;
2080 +       } layer7;
2081 +#endif
2082 +
2083         /* Storage reserved for other modules: */
2084         union nf_conntrack_proto proto;
2085
2086 --- /dev/null
2087 +++ b/include/linux/netfilter/xt_layer7.h
2088 @@ -0,0 +1,13 @@
2089 +#ifndef _XT_LAYER7_H
2090 +#define _XT_LAYER7_H
2091 +
2092 +#define MAX_PATTERN_LEN 8192
2093 +#define MAX_PROTOCOL_LEN 256
2094 +
2095 +struct xt_layer7_info {
2096 +    char protocol[MAX_PROTOCOL_LEN];
2097 +    char pattern[MAX_PATTERN_LEN];
2098 +    u_int8_t invert;
2099 +};
2100 +
2101 +#endif /* _XT_LAYER7_H */