[kernel] update to 2.6.26.5 and 2.6.25.17
[openwrt-10.03/.git] / target / linux / generic-2.6 / patches-2.6.26 / 170-netfilter_chaostables_0.8.patch
1 --- /dev/null
2 +++ b/include/linux/netfilter/oot_conntrack.h
3 @@ -0,0 +1,5 @@
4 +#if defined(CONFIG_IP_NF_CONNTRACK) || defined(CONFIG_IP_NF_CONNTRACK_MODULE)
5 +#      include <linux/netfilter_ipv4/ip_conntrack.h>
6 +#else /* linux-2.6.20+ */
7 +#      include <net/netfilter/nf_nat_rule.h>
8 +#endif
9 --- /dev/null
10 +++ b/include/linux/netfilter/oot_trans.h
11 @@ -0,0 +1,14 @@
12 +/* Out of tree workarounds */
13 +#include <linux/version.h>
14 +#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 18)
15 +#      define HAVE_MATCHINFOSIZE 1
16 +#      define HAVE_TARGUSERINFO 1
17 +#      define HAVE_TARGINFOSIZE 1
18 +#endif
19 +#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20)
20 +#      define nfmark mark
21 +#endif
22 +#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 21)
23 +#      define tcp_v4_check(tcph, tcph_sz, s, d, csp) \
24 +               tcp_v4_check((tcph_sz), (s), (d), (csp))
25 +#endif
26 --- /dev/null
27 +++ b/include/linux/netfilter/xt_CHAOS.h
28 @@ -0,0 +1,14 @@
29 +#ifndef _LINUX_NETFILTER_XT_CHAOS_H
30 +#define _LINUX_NETFILTER_XT_CHAOS_H 1
31 +
32 +enum xt_chaos_target_variant {
33 +       XTCHAOS_NORMAL,
34 +       XTCHAOS_TARPIT,
35 +       XTCHAOS_DELUDE,
36 +};
37 +
38 +struct xt_chaos_target_info {
39 +       uint8_t variant;
40 +};
41 +
42 +#endif /* _LINUX_NETFILTER_XT_CHAOS_H */
43 --- /dev/null
44 +++ b/include/linux/netfilter/xt_portscan.h
45 @@ -0,0 +1,8 @@
46 +#ifndef _LINUX_NETFILTER_XT_PORTSCAN_H
47 +#define _LINUX_NETFILTER_XT_PORTSCAN_H 1
48 +
49 +struct xt_portscan_match_info {
50 +       uint8_t match_stealth, match_syn, match_cn, match_gr;
51 +};
52 +
53 +#endif /* _LINUX_NETFILTER_XT_PORTSCAN_H */
54 --- /dev/null
55 +++ b/net/netfilter/find_match.c
56 @@ -0,0 +1,39 @@
57 +/*
58 +    xt_request_find_match
59 +    by Jan Engelhardt <jengelh [at] gmx de>, 2006 - 2007
60 +
61 +    Based upon linux-2.6.18.5/net/netfilter/x_tables.c:
62 +    Copyright (C) 2006-2006 Harald Welte <laforge@netfilter.org>
63 +    This program is free software; you can redistribute it and/or modify
64 +    it under the terms of the GNU General Public License version 2 as
65 +    published by the Free Software Foundation.
66 +*/
67 +#include <linux/err.h>
68 +#include <linux/netfilter_arp.h>
69 +#include <linux/socket.h>
70 +#include <linux/netfilter/x_tables.h>
71 +
72 +/*
73 + * Yeah this code is sub-optimal, but the function is missing in
74 + * mainline so far. -jengelh
75 + */
76 +static struct xt_match *xt_request_find_match_lo(int af, const char *name,
77 +    u8 revision)
78 +{
79 +       static const char *const xt_prefix[] = {
80 +               [AF_INET]  = "ip",
81 +               [AF_INET6] = "ip6",
82 +               [NF_ARP]   = "arp",
83 +       };
84 +       struct xt_match *match;
85 +
86 +       match = try_then_request_module(xt_find_match(af, name, revision),
87 +               "%st_%s", xt_prefix[af], name);
88 +       if (IS_ERR(match) || match == NULL)
89 +               return NULL;
90 +
91 +       return match;
92 +}
93 +
94 +/* In case it goes into mainline, let this out-of-tree package compile */
95 +#define xt_request_find_match xt_request_find_match_lo
96 --- a/net/netfilter/Kconfig
97 +++ b/net/netfilter/Kconfig
98 @@ -288,6 +288,14 @@
99  
100  # alphabetically ordered list of targets
101  
102 +config NETFILTER_XT_TARGET_CHAOS
103 +       tristate '"CHAOS" target support'
104 +       depends on NETFILTER_XTABLES
105 +       help
106 +         This option adds a `CHAOS' target.
107 +
108 +         To compile it as a module, choose M here.  If unsure, say N.
109 +
110  config NETFILTER_XT_TARGET_CLASSIFY
111         tristate '"CLASSIFY" target support'
112         depends on NETFILTER_XTABLES
113 @@ -317,6 +325,14 @@
114           <file:Documentation/kbuild/modules.txt>.  The module will be called
115           ipt_CONNMARK.ko.  If unsure, say `N'.
116  
117 +config NETFILTER_XT_TARGET_DELUDE
118 +       tristate '"DELUDE" target support'
119 +       depends on NETFILTER_XTABLES
120 +       help
121 +         This option adds a `DELUDE' target.
122 +
123 +         To compile it as a module, choose M here.  If unsure, say N.
124 +
125  config NETFILTER_XT_TARGET_DSCP
126         tristate '"DSCP" and "TOS" target support'
127         depends on NETFILTER_XTABLES
128 @@ -653,6 +669,14 @@
129  
130           To compile it as a module, choose M here.  If unsure, say N.
131  
132 +config NETFILTER_XT_MATCH_PORTSCAN
133 +       tristate '"portscan" match support'
134 +       depends on NETFILTER_XTABLES
135 +       help
136 +         This option adds a 'portscan' match support.
137 +
138 +         To compile it as a module, choose M here.  If unsure, say N.
139 +
140  config NETFILTER_XT_MATCH_MULTIPORT
141         tristate '"multiport" Multiple port match support'
142         depends on NETFILTER_XTABLES
143 --- a/net/netfilter/Makefile
144 +++ b/net/netfilter/Makefile
145 @@ -51,6 +51,8 @@
146  obj-$(CONFIG_NETFILTER_XT_TARGET_TCPMSS) += xt_TCPMSS.o
147  obj-$(CONFIG_NETFILTER_XT_TARGET_TCPOPTSTRIP) += xt_TCPOPTSTRIP.o
148  obj-$(CONFIG_NETFILTER_XT_TARGET_TRACE) += xt_TRACE.o
149 +obj-$(CONFIG_NETFILTER_XT_TARGET_CHAOS) += xt_CHAOS.o
150 +obj-$(CONFIG_NETFILTER_XT_TARGET_DELUDE) += xt_DELUDE.o
151  
152  # matches
153  obj-$(CONFIG_NETFILTER_XT_MATCH_COMMENT) += xt_comment.o
154 @@ -84,3 +86,4 @@
155  obj-$(CONFIG_NETFILTER_XT_MATCH_TCPMSS) += xt_tcpmss.o
156  obj-$(CONFIG_NETFILTER_XT_MATCH_TIME) += xt_time.o
157  obj-$(CONFIG_NETFILTER_XT_MATCH_U32) += xt_u32.o
158 +obj-$(CONFIG_NETFILTER_XT_MATCH_PORTSCAN) += xt_portscan.o
159 --- /dev/null
160 +++ b/net/netfilter/xt_CHAOS.c
161 @@ -0,0 +1,200 @@
162 +/*
163 + *     CHAOS target for netfilter
164 + *     Copyright © CC Computer Consultants GmbH, 2006 - 2007
165 + *     Contact: Jan Engelhardt <jengelh@computergmbh.de>
166 + *
167 + *     This program is free software; you can redistribute it and/or modify
168 + *     it under the terms of the GNU General Public License; either version
169 + *     2 or 3 as published by the Free Software Foundation.
170 + */
171 +#include <linux/icmp.h>
172 +#include <linux/in.h>
173 +#include <linux/ip.h>
174 +#include <linux/module.h>
175 +#include <linux/skbuff.h>
176 +#include <linux/stat.h>
177 +#include <linux/netfilter/x_tables.h>
178 +#include <linux/netfilter/xt_tcpudp.h>
179 +#include <linux/netfilter_ipv4/ipt_REJECT.h>
180 +#include <net/ip.h>
181 +#if defined(_LOCAL)
182 +#      include "xt_CHAOS.h"
183 +#      include "find_match.c"
184 +#elif defined(CONFIG_NETFILTER_XT_TARGET_CHAOS) || \
185 +    defined(CONFIG_NETFILTER_XT_TARGET_CHAOS_MODULE)
186 +#      include <linux/netfilter/xt_CHAOS.h>
187 +#      include "find_match.c"
188 +#else
189 +#      include "xt_CHAOS.h"
190 +#      include "find_match.c"
191 +#endif
192 +#define PFX KBUILD_MODNAME ": "
193 +
194 +/* Module parameters */
195 +static unsigned int reject_percentage = ~0U * .01;
196 +static unsigned int delude_percentage = ~0U * .0101;
197 +module_param(reject_percentage, uint, S_IRUGO | S_IWUSR);
198 +module_param(delude_percentage, uint, S_IRUGO | S_IWUSR);
199 +
200 +/* References to other matches/targets */
201 +static struct xt_match *xm_tcp;
202 +static struct xt_target *xt_delude, *xt_reject, *xt_tarpit;
203 +
204 +static int have_delude, have_tarpit;
205 +
206 +/* Static data for other matches/targets */
207 +static const struct ipt_reject_info reject_params = {
208 +       .with = ICMP_HOST_UNREACH,
209 +};
210 +
211 +static const struct xt_tcp tcp_params = {
212 +       .spts = {0, ~0},
213 +       .dpts = {0, ~0},
214 +};
215 +
216 +/* CHAOS functions */
217 +static void xt_chaos_total(const struct xt_chaos_target_info *info,
218 +    struct sk_buff *skb, const struct net_device *in,
219 +    const struct net_device *out, unsigned int hooknum)
220 +{
221 +       const struct iphdr *iph = ip_hdr(skb);
222 +       const int protoff       = 4 * iph->ihl;
223 +       const int offset        = ntohs(iph->frag_off) & IP_OFFSET;
224 +       const struct xt_target *destiny;
225 +       bool hotdrop = false, ret;
226 +
227 +       ret = xm_tcp->match(skb, in, out, xm_tcp, &tcp_params,
228 +                           offset, protoff, &hotdrop);
229 +       if (!ret || hotdrop || (unsigned int)net_random() > delude_percentage)
230 +               return;
231 +
232 +       destiny = (info->variant == XTCHAOS_TARPIT) ? xt_tarpit : xt_delude;
233 +       destiny->target(skb, in, out, hooknum, destiny, NULL);
234 +       return;
235 +}
236 +
237 +static unsigned int chaos_tg(struct sk_buff *skb,
238 +    const struct net_device *in, const struct net_device *out,
239 +    unsigned int hooknum, const struct xt_target *target, const void *targinfo)
240 +{
241 +       /*
242 +        * Equivalent to:
243 +        * -A chaos -m statistic --mode random --probability \
244 +        *         $reject_percentage -j REJECT --reject-with host-unreach;
245 +        * -A chaos -p tcp -m statistic --mode random --probability \
246 +        *         $delude_percentage -j DELUDE;
247 +        * -A chaos -j DROP;
248 +        */
249 +       const struct xt_chaos_target_info *info = targinfo;
250 +       const struct iphdr *iph = ip_hdr(skb);
251 +
252 +       if ((unsigned int)net_random() <= reject_percentage)
253 +               return xt_reject->target(skb, in, out, hooknum, target,
254 +                      &reject_params);
255 +
256 +       /* TARPIT/DELUDE may not be called from the OUTPUT chain */
257 +       if (iph->protocol == IPPROTO_TCP &&
258 +           info->variant != XTCHAOS_NORMAL && hooknum != NF_INET_LOCAL_OUT)
259 +               xt_chaos_total(info, skb, in, out, hooknum);
260 +
261 +       return NF_DROP;
262 +}
263 +
264 +static bool chaos_tg_check(const char *tablename, const void *entry,
265 +    const struct xt_target *target, void *targinfo, unsigned int hook_mask)
266 +{
267 +       const struct xt_chaos_target_info *info = targinfo;
268 +
269 +       if (info->variant == XTCHAOS_DELUDE && !have_delude) {
270 +               printk(KERN_WARNING PFX "Error: Cannot use --delude when "
271 +                      "DELUDE module not available\n");
272 +               return false;
273 +       }
274 +       if (info->variant == XTCHAOS_TARPIT && !have_tarpit) {
275 +               printk(KERN_WARNING PFX "Error: Cannot use --tarpit when "
276 +                      "TARPIT module not available\n");
277 +               return false;
278 +       }
279 +
280 +       return true;
281 +}
282 +
283 +static struct xt_target chaos_tg_reg = {
284 +       .name       = "CHAOS",
285 +       .family     = AF_INET,
286 +       .table      = "filter",
287 +       .hooks      = (1 << NF_INET_LOCAL_IN) | (1 << NF_INET_FORWARD) |
288 +                     (1 << NF_INET_LOCAL_OUT),
289 +       .checkentry = chaos_tg_check,
290 +       .target     = chaos_tg,
291 +       .targetsize = sizeof(struct xt_chaos_target_info),
292 +       .me         = THIS_MODULE,
293 +};
294 +
295 +static int __init chaos_tg_init(void)
296 +{
297 +       int ret = -EINVAL;
298 +
299 +       xm_tcp = xt_request_find_match(AF_INET, "tcp", 0);
300 +       if (xm_tcp == NULL) {
301 +               printk(KERN_WARNING PFX "Error: Could not find or load "
302 +                      "\"tcp\" match\n");
303 +               return -EINVAL;
304 +       }
305 +
306 +       xt_reject = xt_request_find_target(AF_INET, "REJECT", 0);
307 +       if (xt_reject == NULL) {
308 +               printk(KERN_WARNING PFX "Error: Could not find or load "
309 +                      "\"REJECT\" target\n");
310 +               goto out2;
311 +       }
312 +
313 +       xt_tarpit   = xt_request_find_target(AF_INET, "TARPIT", 0);
314 +       have_tarpit = xt_tarpit != NULL;
315 +       if (!have_tarpit)
316 +               printk(KERN_WARNING PFX "Warning: Could not find or load "
317 +                      "\"TARPIT\" target\n");
318 +
319 +       xt_delude   = xt_request_find_target(AF_INET, "DELUDE", 0);
320 +       have_delude = xt_delude != NULL;
321 +       if (!have_delude)
322 +               printk(KERN_WARNING PFX "Warning: Could not find or load "
323 +                      "\"DELUDE\" target\n");
324 +
325 +       if ((ret = xt_register_target(&chaos_tg_reg)) != 0) {
326 +               printk(KERN_WARNING PFX "xt_register_target returned "
327 +                      "error %d\n", ret);
328 +               goto out3;
329 +       }
330 +
331 +       return 0;
332 +
333 + out3:
334 +       if (have_delude)
335 +               module_put(xt_delude->me);
336 +       if (have_tarpit)
337 +               module_put(xt_tarpit->me);
338 +       module_put(xt_reject->me);
339 + out2:
340 +       module_put(xm_tcp->me);
341 +       return ret;
342 +}
343 +
344 +static void __exit chaos_tg_exit(void)
345 +{
346 +       xt_unregister_target(&chaos_tg_reg);
347 +       module_put(xm_tcp->me);
348 +       module_put(xt_reject->me);
349 +       if (have_delude)
350 +               module_put(xt_delude->me);
351 +       if (have_tarpit)
352 +               module_put(xt_tarpit->me);
353 +       return;
354 +}
355 +
356 +module_init(chaos_tg_init);
357 +module_exit(chaos_tg_exit);
358 +MODULE_AUTHOR("Jan Engelhardt <jengelh@computergmbh.de>");
359 +MODULE_DESCRIPTION("netfilter \"CHAOS\" target");
360 +MODULE_LICENSE("GPL");
361 +MODULE_ALIAS("ipt_CHAOS");
362 --- /dev/null
363 +++ b/net/netfilter/xt_DELUDE.c
364 @@ -0,0 +1,197 @@
365 +/*
366 + *     DELUDE target
367 + *     Copyright © CC Computer Consultants GmbH, 2007
368 + *     Contact: Jan Engelhardt <jengelh@computergmbh.de>
369 + *
370 + *     Based upon linux-2.6.18.5/net/ipv4/netfilter/ipt_REJECT.c:
371 + *     (C) 1999-2001 Paul `Rusty' Russell
372 + *     (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
373 + *
374 + *     xt_DELUDE acts like REJECT, but does reply with SYN-ACK on SYN.
375 + *
376 + *     This program is free software; you can redistribute it and/or modify
377 + *     it under the terms of the GNU General Public License version 2 as
378 + *     published by the Free Software Foundation.
379 + */
380 +#include <linux/module.h>
381 +#include <linux/skbuff.h>
382 +#include <linux/ip.h>
383 +#include <linux/tcp.h>
384 +#include <linux/netfilter/x_tables.h>
385 +#ifdef CONFIG_BRIDGE_NETFILTER
386 +#      include <linux/netfilter_bridge.h>
387 +#endif
388 +#include <net/tcp.h>
389 +#define PFX KBUILD_MODNAME ": "
390 +
391 +static void delude_send_reset(struct sk_buff *oldskb, unsigned int hook)
392 +{
393 +       struct tcphdr _otcph, *oth, *tcph;
394 +       unsigned int addr_type;
395 +       struct sk_buff *nskb;
396 +       u_int16_t tmp_port;
397 +       u_int32_t tmp_addr;
398 +       struct iphdr *niph;
399 +       bool needs_ack;
400 +
401 +       /* IP header checks: fragment. */
402 +       if (ip_hdr(oldskb)->frag_off & htons(IP_OFFSET))
403 +               return;
404 +
405 +       oth = skb_header_pointer(oldskb, ip_hdrlen(oldskb),
406 +                                sizeof(_otcph), &_otcph);
407 +       if (oth == NULL)
408 +               return;
409 +
410 +       /* No RST for RST. */
411 +       if (oth->rst)
412 +               return;
413 +
414 +       /* Check checksum */
415 +       if (nf_ip_checksum(oldskb, hook, ip_hdrlen(oldskb), IPPROTO_TCP))
416 +               return;
417 +
418 +       /* We need a linear, writeable skb.  We also need to expand
419 +          headroom in case hh_len of incoming interface < hh_len of
420 +          outgoing interface */
421 +       nskb = skb_copy_expand(oldskb, LL_MAX_HEADER, skb_tailroom(oldskb),
422 +                              GFP_ATOMIC);
423 +       if (!nskb)
424 +               return;
425 +
426 +       /* This packet will not be the same as the other: clear nf fields */
427 +       nf_reset(nskb);
428 +       nskb->mark = 0;
429 +       skb_init_secmark(nskb);
430 +
431 +       skb_shinfo(nskb)->gso_size = 0;
432 +       skb_shinfo(nskb)->gso_segs = 0;
433 +       skb_shinfo(nskb)->gso_type = 0;
434 +
435 +       tcph = (struct tcphdr *)(skb_network_header(nskb) + ip_hdrlen(nskb));
436 +
437 +       /* Swap source and dest */
438 +       niph         = ip_hdr(nskb);
439 +       tmp_addr     = niph->saddr;
440 +       niph->saddr  = niph->daddr;
441 +       niph->daddr  = tmp_addr;
442 +       tmp_port     = tcph->source;
443 +       tcph->source = tcph->dest;
444 +       tcph->dest   = tmp_port;
445 +
446 +       /* Truncate to length (no data) */
447 +       tcph->doff    = sizeof(struct tcphdr) / 4;
448 +       skb_trim(nskb, ip_hdrlen(nskb) + sizeof(struct tcphdr));
449 +       niph->tot_len = htons(nskb->len);
450 +
451 +       if (oth->syn && !oth->ack && !oth->rst && !oth->fin) {
452 +               /* DELUDE essential part */
453 +               tcph->ack_seq = htonl(ntohl(oth->seq) + oth->syn + oth->fin +
454 +                               oldskb->len - ip_hdrlen(oldskb) -
455 +                               (oth->doff << 2));
456 +               tcph->seq     = false;
457 +               tcph->ack     = true;
458 +       } else {
459 +               if (!tcph->ack) {
460 +                       needs_ack     = true;
461 +                       tcph->ack_seq = htonl(ntohl(oth->seq) + oth->syn +
462 +                                       oth->fin + oldskb->len -
463 +                                       ip_hdrlen(oldskb) - (oth->doff<<2));
464 +                       tcph->seq     = false;
465 +               } else {
466 +                       needs_ack     = false;
467 +                       tcph->seq     = oth->ack_seq;
468 +                       tcph->ack_seq = false;
469 +               }
470 +
471 +               /* Reset flags */
472 +               ((u_int8_t *)tcph)[13] = 0;
473 +               tcph->rst = true;
474 +               tcph->ack = needs_ack;
475 +       }
476 +
477 +       tcph->window  = 0;
478 +       tcph->urg_ptr = 0;
479 +
480 +       /* Adjust TCP checksum */
481 +       tcph->check = 0;
482 +       tcph->check = tcp_v4_check(sizeof(struct tcphdr), niph->saddr,
483 +                     niph->daddr, csum_partial((char *)tcph,
484 +                     sizeof(struct tcphdr), 0));
485 +
486 +       /* Set DF, id = 0 */
487 +       niph->frag_off = htons(IP_DF);
488 +       niph->id       = 0;
489 +
490 +       addr_type = RTN_UNSPEC;
491 +#ifdef CONFIG_BRIDGE_NETFILTER
492 +       if (hook != NF_INET_FORWARD || (nskb->nf_bridge != NULL &&
493 +           nskb->nf_bridge->mask & BRNF_BRIDGED))
494 +#else
495 +       if (hook != NF_INET_FORWARD)
496 +#endif
497 +               addr_type = RTN_LOCAL;
498 +
499 +       if (ip_route_me_harder(nskb, addr_type))
500 +               goto free_nskb;
501 +
502 +       nskb->ip_summed = CHECKSUM_NONE;
503 +
504 +       /* Adjust IP TTL */
505 +       niph->ttl = dst_metric(nskb->dst, RTAX_HOPLIMIT);
506 +
507 +       /* Adjust IP checksum */
508 +       niph->check = 0;
509 +       niph->check = ip_fast_csum(skb_network_header(nskb), niph->ihl);
510 +
511 +       /* "Never happens" */
512 +       if (nskb->len > dst_mtu(nskb->dst))
513 +               goto free_nskb;
514 +
515 +       nf_ct_attach(nskb, oldskb);
516 +
517 +       NF_HOOK(PF_INET, NF_INET_LOCAL_OUT, nskb, NULL, nskb->dst->dev,
518 +               dst_output);
519 +       return;
520 +
521 + free_nskb:
522 +       kfree_skb(nskb);
523 +}
524 +
525 +static unsigned int delude_tg(struct sk_buff *skb,
526 +    const struct net_device *in, const struct net_device *out,
527 +    unsigned int hooknum, const struct xt_target *target, const void *targinfo)
528 +{
529 +       /* WARNING: This code causes reentry within iptables.
530 +          This means that the iptables jump stack is now crap.  We
531 +          must return an absolute verdict. --RR */
532 +       delude_send_reset(skb, hooknum);
533 +       return NF_DROP;
534 +}
535 +
536 +static struct xt_target delude_tg_reg = {
537 +       .name       = "DELUDE",
538 +       .family     = AF_INET,
539 +       .table      = "filter",
540 +       .hooks      = (1 << NF_INET_LOCAL_IN) | (1 << NF_INET_FORWARD),
541 +       .target     = delude_tg,
542 +       .proto      = IPPROTO_TCP,
543 +       .me         = THIS_MODULE,
544 +};
545 +
546 +static int __init delude_tg_init(void)
547 +{
548 +       return xt_register_target(&delude_tg_reg);
549 +}
550 +
551 +static void __exit delude_tg_exit(void)
552 +{
553 +       xt_unregister_target(&delude_tg_reg);
554 +}
555 +
556 +module_init(delude_tg_init);
557 +module_exit(delude_tg_exit);
558 +MODULE_AUTHOR("Jan Engelhardt <jengelh@computergmbh.de>");
559 +MODULE_DESCRIPTION("netfilter \"DELUDE\" target");
560 +MODULE_LICENSE("GPL");
561 +MODULE_ALIAS("ipt_DELUDE");
562 --- /dev/null
563 +++ b/net/netfilter/xt_portscan.c
564 @@ -0,0 +1,269 @@
565 +/*
566 + *     portscan match for netfilter
567 + *     Copyright © CC Computer Consultants GmbH, 2006 - 2007
568 + *     Contact: Jan Engelhardt <jengelh@computergmbh.de>
569 + *
570 + *     This program is free software; you can redistribute it and/or modify
571 + *     it under the terms of the GNU General Public License; either version
572 + *     2 or 3 as published by the Free Software Foundation.
573 + */
574 +#include <linux/in.h>
575 +#include <linux/ip.h>
576 +#include <linux/module.h>
577 +#include <linux/moduleparam.h>
578 +#include <linux/skbuff.h>
579 +#include <linux/stat.h>
580 +#include <linux/tcp.h>
581 +#include <linux/types.h>
582 +#include <linux/version.h>
583 +#include <linux/netfilter/x_tables.h>
584 +#include <linux/netfilter/xt_tcpudp.h>
585 +#include <net/netfilter/nf_nat_rule.h>
586 +#if defined(_LOCAL)
587 +#      include "xt_portscan.h"
588 +#elif defined(CONFIG_NETFILTER_XT_MATCH_PORTSCAN) || \
589 +    defined(CONFIG_NETFILTER_XT_MATCH_PORTSCAN_MODULE)
590 +#      include <linux/netfilter/xt_portscan.h>
591 +#else
592 +#      include "xt_portscan.h"
593 +#endif
594 +#define PFX KBUILD_MODNAME ": "
595 +
596 +enum {
597 +       TCP_FLAGS_ALL3 = TCP_FLAG_FIN | TCP_FLAG_RST | TCP_FLAG_SYN,
598 +       TCP_FLAGS_ALL4 = TCP_FLAGS_ALL3 | TCP_FLAG_ACK,
599 +       TCP_FLAGS_ALL6 = TCP_FLAGS_ALL4 | TCP_FLAG_PSH | TCP_FLAG_URG,
600 +};
601 +
602 +/* Module parameters */
603 +static unsigned int
604 +       connmark_mask = ~0,
605 +       packet_mask   = ~0,
606 +       mark_seen     = 0x9,
607 +       mark_synrcv   = 0x1,
608 +       mark_closed   = 0x2,
609 +       mark_synscan  = 0x3,
610 +       mark_estab1   = 0x4,
611 +       mark_estab2   = 0x5,
612 +       mark_cnscan   = 0x6,
613 +       mark_grscan   = 0x7,
614 +       mark_valid    = 0x8;
615 +
616 +module_param(connmark_mask, uint, S_IRUGO | S_IWUSR);
617 +module_param(packet_mask,   uint, S_IRUGO | S_IWUSR);
618 +module_param(mark_seen,     uint, S_IRUGO | S_IWUSR);
619 +module_param(mark_synrcv,   uint, S_IRUGO | S_IWUSR);
620 +module_param(mark_closed,   uint, S_IRUGO | S_IWUSR);
621 +module_param(mark_synscan,  uint, S_IRUGO | S_IWUSR);
622 +module_param(mark_estab1,   uint, S_IRUGO | S_IWUSR);
623 +module_param(mark_estab2,   uint, S_IRUGO | S_IWUSR);
624 +module_param(mark_cnscan,   uint, S_IRUGO | S_IWUSR);
625 +module_param(mark_grscan,   uint, S_IRUGO | S_IWUSR);
626 +module_param(mark_valid,    uint, S_IRUGO | S_IWUSR);
627 +MODULE_PARM_DESC(connmark_mask, "only set specified bits in connection mark");
628 +MODULE_PARM_DESC(packet_mask,   "only set specified bits in packet mark");
629 +MODULE_PARM_DESC(mark_seen,     "nfmark value for packet-seen state");
630 +MODULE_PARM_DESC(mark_synrcv,   "connmark value for SYN Received state");
631 +MODULE_PARM_DESC(mark_closed,   "connmark value for closed state");
632 +MODULE_PARM_DESC(mark_synscan,  "connmark value for SYN Scan state");
633 +MODULE_PARM_DESC(mark_estab1,   "connmark value for Established-1 state");
634 +MODULE_PARM_DESC(mark_estab2,   "connmark value for Established-2 state");
635 +MODULE_PARM_DESC(mark_cnscan,   "connmark value for Connect Scan state");
636 +MODULE_PARM_DESC(mark_grscan,   "connmark value for Grab Scan state");
637 +MODULE_PARM_DESC(mark_valid,    "connmark value for Valid state");
638 +
639 +/* TCP flag functions */
640 +static inline bool tflg_ack4(const struct tcphdr *th)
641 +{
642 +       return (tcp_flag_word(th) & TCP_FLAGS_ALL4) == TCP_FLAG_ACK;
643 +}
644 +
645 +static inline bool tflg_ack6(const struct tcphdr *th)
646 +{
647 +       return (tcp_flag_word(th) & TCP_FLAGS_ALL6) == TCP_FLAG_ACK;
648 +}
649 +
650 +static inline bool tflg_fin(const struct tcphdr *th)
651 +{
652 +       return (tcp_flag_word(th) & TCP_FLAGS_ALL3) == TCP_FLAG_FIN;
653 +}
654 +
655 +static inline bool tflg_rst(const struct tcphdr *th)
656 +{
657 +       return (tcp_flag_word(th) & TCP_FLAGS_ALL3) == TCP_FLAG_RST;
658 +}
659 +
660 +static inline bool tflg_rstack(const struct tcphdr *th)
661 +{
662 +       return (tcp_flag_word(th) & TCP_FLAGS_ALL4) ==
663 +              (TCP_FLAG_ACK | TCP_FLAG_RST);
664 +}
665 +
666 +static inline bool tflg_syn(const struct tcphdr *th)
667 +{
668 +       return (tcp_flag_word(th) & TCP_FLAGS_ALL4) == TCP_FLAG_SYN;
669 +}
670 +
671 +static inline bool tflg_synack(const struct tcphdr *th)
672 +{
673 +       return (tcp_flag_word(th) & TCP_FLAGS_ALL4) ==
674 +              (TCP_FLAG_SYN | TCP_FLAG_ACK);
675 +}
676 +
677 +/* portscan functions */
678 +static inline bool portscan_mt_stealth(const struct tcphdr *th)
679 +{
680 +       /*
681 +        * "Connection refused" replies to our own probes must not be matched.
682 +        */
683 +       if (tflg_rstack(th))
684 +               return false;
685 +
686 +       if (tflg_rst(th) && printk_ratelimit()) {
687 +               printk(KERN_WARNING PFX "Warning: Pure RST received\n");
688 +               return false;
689 +       }
690 +
691 +       /*
692 +        * -p tcp ! --syn -m conntrack --ctstate INVALID: Looking for non-start
693 +        * packets that are not associated with any connection -- this will
694 +        * match most scan types (NULL, XMAS, FIN) and ridiculous flag
695 +        * combinations (SYN-RST, SYN-FIN, SYN-FIN-RST, FIN-RST, etc.).
696 +        */
697 +       return !tflg_syn(th);
698 +}
699 +
700 +static inline unsigned int portscan_mt_full(int mark,
701 +    enum ip_conntrack_info ctstate, bool loopback, const struct tcphdr *tcph,
702 +    unsigned int payload_len)
703 +{
704 +       if (mark == mark_estab2) {
705 +               /*
706 +                * -m connmark --mark $ESTAB2
707 +                */
708 +               if (tflg_ack4(tcph) && payload_len == 0)
709 +                       return mark; /* keep mark */
710 +               else if (tflg_rst(tcph) || tflg_fin(tcph))
711 +                       return mark_grscan;
712 +               else
713 +                       return mark_valid;
714 +       } else if (mark == mark_estab1) {
715 +               /*
716 +                * -m connmark --mark $ESTAB1
717 +                */
718 +               if (tflg_rst(tcph) || tflg_fin(tcph))
719 +                       return mark_cnscan;
720 +               else if (!loopback && tflg_ack4(tcph) && payload_len == 0)
721 +                       return mark_estab2;
722 +               else
723 +                       return mark_valid;
724 +       } else if (mark == mark_synrcv) {
725 +               /*
726 +                * -m connmark --mark $SYN
727 +                */
728 +               if (loopback && tflg_synack(tcph))
729 +                       return mark; /* keep mark */
730 +               else if (loopback && tflg_rstack(tcph))
731 +                       return mark_closed;
732 +               else if (tflg_ack6(tcph))
733 +                       return mark_estab1;
734 +               else
735 +                       return mark_synscan;
736 +       } else if (ctstate == IP_CT_NEW && tflg_syn(tcph)) {
737 +               /*
738 +                * -p tcp --syn --ctstate NEW
739 +                */
740 +               return mark_synrcv;
741 +       }
742 +       return mark;
743 +}
744 +
745 +static bool portscan_mt(const struct sk_buff *skb,
746 +    const struct net_device *in, const struct net_device *out,
747 +    const struct xt_match *match, const void *matchinfo, int offset,
748 +    unsigned int protoff, bool *hotdrop)
749 +{
750 +       const struct xt_portscan_match_info *info = matchinfo;
751 +       enum ip_conntrack_info ctstate;
752 +       const struct tcphdr *tcph;
753 +       struct nf_conn *ctdata;
754 +       struct tcphdr tcph_buf;
755 +
756 +       tcph = skb_header_pointer(skb, protoff, sizeof(tcph_buf), &tcph_buf);
757 +       if (tcph == NULL)
758 +               return false;
759 +
760 +       /* Check for invalid packets: -m conntrack --ctstate INVALID */
761 +       if ((ctdata = nf_ct_get(skb, &ctstate)) == NULL) {
762 +               if (info->match_stealth)
763 +                       return portscan_mt_stealth(tcph);
764 +               /*
765 +                * If @ctdata is NULL, we cannot match the other scan
766 +                * types, return.
767 +                */
768 +               return false;
769 +       }
770 +
771 +       /*
772 +        * If -m portscan was previously applied to this packet, the rules we
773 +        * simulate must not be run through again. And for speedup, do not call
774 +        * it either when the connection is already VALID.
775 +        */
776 +       if ((ctdata->mark & connmark_mask) == mark_valid ||
777 +            (skb->mark & packet_mask) != mark_seen) {
778 +               unsigned int n;
779 +
780 +               n = portscan_mt_full(ctdata->mark & connmark_mask, ctstate,
781 +                   (in->flags & IFF_LOOPBACK) == IFF_LOOPBACK, tcph,
782 +                   skb->len - protoff - 4 * tcph->doff);
783 +
784 +               ctdata->mark = (ctdata->mark & ~connmark_mask) | n;
785 +               ((struct sk_buff *)skb)->mark =
786 +                       (skb->mark & ~packet_mask) ^ mark_seen;
787 +       }
788 +
789 +       return (info->match_syn && ctdata->mark == mark_synscan) ||
790 +              (info->match_cn && ctdata->mark == mark_cnscan) ||
791 +              (info->match_gr && ctdata->mark == mark_grscan);
792 +}
793 +
794 +static bool portscan_mt_check(const char *tablename, const void *entry,
795 +    const struct xt_match *match, void *matchinfo, unsigned int hook_mask)
796 +{
797 +       const struct xt_portscan_match_info *info = matchinfo;
798 +
799 +       if ((info->match_stealth & ~1) || (info->match_syn & ~1) ||
800 +           (info->match_cn & ~1) || (info->match_gr & ~1)) {
801 +               printk(KERN_WARNING PFX "Invalid flags\n");
802 +               return false;
803 +       }
804 +       return true;
805 +}
806 +
807 +static struct xt_match portscan_mt_reg __read_mostly = {
808 +       .name       = "portscan",
809 +       .family     = AF_INET,
810 +       .match      = portscan_mt,
811 +       .checkentry = portscan_mt_check,
812 +       .matchsize  = sizeof(struct xt_portscan_match_info),
813 +       .proto      = IPPROTO_TCP,
814 +       .me         = THIS_MODULE,
815 +};
816 +
817 +static int __init portscan_mt_init(void)
818 +{
819 +       return xt_register_match(&portscan_mt_reg);
820 +}
821 +
822 +static void __exit portscan_mt_exit(void)
823 +{
824 +       xt_unregister_match(&portscan_mt_reg);
825 +       return;
826 +}
827 +
828 +module_init(portscan_mt_init);
829 +module_exit(portscan_mt_exit);
830 +MODULE_AUTHOR("Jan Engelhardt <jengelh@computergmbh.de>");
831 +MODULE_DESCRIPTION("netfilter \"portscan\" match");
832 +MODULE_LICENSE("GPL");
833 +MODULE_ALIAS("ipt_portscan");
834 --- a/drivers/char/random.c
835 +++ b/drivers/char/random.c
836 @@ -1554,6 +1554,8 @@
837         return seq;
838  }
839  
840 +EXPORT_SYMBOL(secure_tcp_sequence_number);
841 +
842  /* Generate secure starting point for ephemeral IPV4 transport port search */
843  u32 secure_ipv4_port_ephemeral(__be32 saddr, __be32 daddr, __be16 dport)
844  {