2 * This is a module which is used for logging packets.
5 /* (C) 2001 Jan Rekorajski <baggins@pld.org.pl>
6 * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
13 #include <linux/module.h>
14 #include <linux/moduleparam.h>
15 #include <linux/skbuff.h>
17 #include <linux/spinlock.h>
18 #include <linux/icmpv6.h>
22 #include <linux/netfilter.h>
23 #include <linux/netfilter_ipv6/ip6_tables.h>
25 MODULE_AUTHOR("Jan Rekorajski <baggins@pld.org.pl>");
26 MODULE_DESCRIPTION("IP6 tables LOG target module");
27 MODULE_LICENSE("GPL");
29 static unsigned int nflog
= 1;
30 module_param(nflog
, int, 0400);
31 MODULE_PARM_DESC(nflog
, "register as internal netfilter logging module");
34 #include <net/route.h>
35 #include <linux/netfilter_ipv6/ip6t_LOG.h>
40 #define DEBUGP(format, args...)
43 /* Use lock to serialize, so printks don't overlap */
44 static DEFINE_SPINLOCK(log_lock
);
46 /* One level of recursion won't kill us */
47 static void dump_packet(const struct ip6t_log_info
*info
,
48 const struct sk_buff
*skb
, unsigned int ip6hoff
,
53 struct ipv6hdr _ip6h
, *ih
;
55 unsigned int hdrlen
= 0;
57 ih
= skb_header_pointer(skb
, ip6hoff
, sizeof(_ip6h
), &_ip6h
);
63 /* Max length: 88 "SRC=0000.0000.0000.0000.0000.0000.0000.0000 DST=0000.0000.0000.0000.0000.0000.0000.0000" */
64 printk("SRC=%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x ", NIP6(ih
->saddr
));
65 printk("DST=%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x ", NIP6(ih
->daddr
));
67 /* Max length: 44 "LEN=65535 TC=255 HOPLIMIT=255 FLOWLBL=FFFFF " */
68 printk("LEN=%Zu TC=%u HOPLIMIT=%u FLOWLBL=%u ",
69 ntohs(ih
->payload_len
) + sizeof(struct ipv6hdr
),
70 (ntohl(*(u_int32_t
*)ih
) & 0x0ff00000) >> 20,
72 (ntohl(*(u_int32_t
*)ih
) & 0x000fffff));
75 ptr
= ip6hoff
+ sizeof(struct ipv6hdr
);
76 currenthdr
= ih
->nexthdr
;
77 while (currenthdr
!= NEXTHDR_NONE
&& ip6t_ext_hdr(currenthdr
)) {
78 struct ipv6_opt_hdr _hdr
, *hp
;
80 hp
= skb_header_pointer(skb
, ptr
, sizeof(_hdr
), &_hdr
);
86 /* Max length: 48 "OPT (...) " */
87 if (info
->logflags
& IP6T_LOG_IPOPT
)
91 case IPPROTO_FRAGMENT
: {
92 struct frag_hdr _fhdr
, *fh
;
95 fh
= skb_header_pointer(skb
, ptr
, sizeof(_fhdr
),
102 /* Max length: 6 "65535 " */
103 printk("%u ", ntohs(fh
->frag_off
) & 0xFFF8);
105 /* Max length: 11 "INCOMPLETE " */
106 if (fh
->frag_off
& htons(0x0001))
107 printk("INCOMPLETE ");
109 printk("ID:%08x ", ntohl(fh
->identification
));
111 if (ntohs(fh
->frag_off
) & 0xFFF8)
118 case IPPROTO_DSTOPTS
:
119 case IPPROTO_ROUTING
:
120 case IPPROTO_HOPOPTS
:
122 if (info
->logflags
& IP6T_LOG_IPOPT
)
126 hdrlen
= ipv6_optlen(hp
);
130 if (info
->logflags
& IP6T_LOG_IPOPT
) {
131 struct ip_auth_hdr _ahdr
, *ah
;
133 /* Max length: 3 "AH " */
141 ah
= skb_header_pointer(skb
, ptr
, sizeof(_ahdr
),
145 * Max length: 26 "INCOMPLETE [65535
148 printk("INCOMPLETE [%u bytes] )",
153 /* Length: 15 "SPI=0xF1234567 */
154 printk("SPI=0x%x ", ntohl(ah
->spi
));
158 hdrlen
= (hp
->hdrlen
+2)<<2;
161 if (info
->logflags
& IP6T_LOG_IPOPT
) {
162 struct ip_esp_hdr _esph
, *eh
;
164 /* Max length: 4 "ESP " */
173 * Max length: 26 "INCOMPLETE [65535 bytes] )"
175 eh
= skb_header_pointer(skb
, ptr
, sizeof(_esph
),
178 printk("INCOMPLETE [%u bytes] )",
183 /* Length: 16 "SPI=0xF1234567 )" */
184 printk("SPI=0x%x )", ntohl(eh
->spi
) );
189 /* Max length: 20 "Unknown Ext Hdr 255" */
190 printk("Unknown Ext Hdr %u", currenthdr
);
193 if (info
->logflags
& IP6T_LOG_IPOPT
)
196 currenthdr
= hp
->nexthdr
;
200 switch (currenthdr
) {
202 struct tcphdr _tcph
, *th
;
204 /* Max length: 10 "PROTO=TCP " */
205 printk("PROTO=TCP ");
210 /* Max length: 25 "INCOMPLETE [65535 bytes] " */
211 th
= skb_header_pointer(skb
, ptr
, sizeof(_tcph
), &_tcph
);
213 printk("INCOMPLETE [%u bytes] ", skb
->len
- ptr
);
217 /* Max length: 20 "SPT=65535 DPT=65535 " */
218 printk("SPT=%u DPT=%u ",
219 ntohs(th
->source
), ntohs(th
->dest
));
220 /* Max length: 30 "SEQ=4294967295 ACK=4294967295 " */
221 if (info
->logflags
& IP6T_LOG_TCPSEQ
)
222 printk("SEQ=%u ACK=%u ",
223 ntohl(th
->seq
), ntohl(th
->ack_seq
));
224 /* Max length: 13 "WINDOW=65535 " */
225 printk("WINDOW=%u ", ntohs(th
->window
));
226 /* Max length: 9 "RES=0x3C " */
227 printk("RES=0x%02x ", (u_int8_t
)(ntohl(tcp_flag_word(th
) & TCP_RESERVED_BITS
) >> 22));
228 /* Max length: 32 "CWR ECE URG ACK PSH RST SYN FIN " */
245 /* Max length: 11 "URGP=65535 " */
246 printk("URGP=%u ", ntohs(th
->urg_ptr
));
248 if ((info
->logflags
& IP6T_LOG_TCPOPT
)
249 && th
->doff
* 4 > sizeof(struct tcphdr
)) {
250 u_int8_t _opt
[60 - sizeof(struct tcphdr
)], *op
;
252 unsigned int optsize
= th
->doff
* 4
253 - sizeof(struct tcphdr
);
255 op
= skb_header_pointer(skb
,
256 ptr
+ sizeof(struct tcphdr
),
259 printk("OPT (TRUNCATED)");
263 /* Max length: 127 "OPT (" 15*4*2chars ") " */
265 for (i
=0; i
< optsize
; i
++)
266 printk("%02X", op
[i
]);
272 struct udphdr _udph
, *uh
;
274 /* Max length: 10 "PROTO=UDP " */
275 printk("PROTO=UDP ");
280 /* Max length: 25 "INCOMPLETE [65535 bytes] " */
281 uh
= skb_header_pointer(skb
, ptr
, sizeof(_udph
), &_udph
);
283 printk("INCOMPLETE [%u bytes] ", skb
->len
- ptr
);
287 /* Max length: 20 "SPT=65535 DPT=65535 " */
288 printk("SPT=%u DPT=%u LEN=%u ",
289 ntohs(uh
->source
), ntohs(uh
->dest
),
293 case IPPROTO_ICMPV6
: {
294 struct icmp6hdr _icmp6h
, *ic
;
296 /* Max length: 13 "PROTO=ICMPv6 " */
297 printk("PROTO=ICMPv6 ");
302 /* Max length: 25 "INCOMPLETE [65535 bytes] " */
303 ic
= skb_header_pointer(skb
, ptr
, sizeof(_icmp6h
), &_icmp6h
);
305 printk("INCOMPLETE [%u bytes] ", skb
->len
- ptr
);
309 /* Max length: 18 "TYPE=255 CODE=255 " */
310 printk("TYPE=%u CODE=%u ", ic
->icmp6_type
, ic
->icmp6_code
);
312 switch (ic
->icmp6_type
) {
313 case ICMPV6_ECHO_REQUEST
:
314 case ICMPV6_ECHO_REPLY
:
315 /* Max length: 19 "ID=65535 SEQ=65535 " */
316 printk("ID=%u SEQ=%u ",
317 ntohs(ic
->icmp6_identifier
),
318 ntohs(ic
->icmp6_sequence
));
320 case ICMPV6_MGM_QUERY
:
321 case ICMPV6_MGM_REPORT
:
322 case ICMPV6_MGM_REDUCTION
:
325 case ICMPV6_PARAMPROB
:
326 /* Max length: 17 "POINTER=ffffffff " */
327 printk("POINTER=%08x ", ntohl(ic
->icmp6_pointer
));
329 case ICMPV6_DEST_UNREACH
:
330 case ICMPV6_PKT_TOOBIG
:
331 case ICMPV6_TIME_EXCEED
:
332 /* Max length: 3+maxlen */
335 dump_packet(info
, skb
, ptr
+ sizeof(_icmp6h
),
340 /* Max length: 10 "MTU=65535 " */
341 if (ic
->icmp6_type
== ICMPV6_PKT_TOOBIG
)
342 printk("MTU=%u ", ntohl(ic
->icmp6_mtu
));
346 /* Max length: 10 "PROTO=255 " */
348 printk("PROTO=%u ", currenthdr
);
351 /* Max length: 15 "UID=4294967295 " */
352 if ((info
->logflags
& IP6T_LOG_UID
) && recurse
&& skb
->sk
) {
353 read_lock_bh(&skb
->sk
->sk_callback_lock
);
354 if (skb
->sk
->sk_socket
&& skb
->sk
->sk_socket
->file
)
355 printk("UID=%u ", skb
->sk
->sk_socket
->file
->f_uid
);
356 read_unlock_bh(&skb
->sk
->sk_callback_lock
);
361 ip6t_log_packet(unsigned int hooknum
,
362 const struct sk_buff
*skb
,
363 const struct net_device
*in
,
364 const struct net_device
*out
,
365 const struct ip6t_log_info
*loginfo
,
366 const char *level_string
,
369 struct ipv6hdr
*ipv6h
= skb
->nh
.ipv6h
;
371 spin_lock_bh(&log_lock
);
372 printk(level_string
);
373 printk("%sIN=%s OUT=%s ",
374 prefix
== NULL
? loginfo
->prefix
: prefix
,
376 out
? out
->name
: "");
378 /* MAC logging for input chain only. */
380 if (skb
->dev
&& skb
->dev
->hard_header_len
&& skb
->mac
.raw
!= (void*)ipv6h
) {
381 if (skb
->dev
->type
!= ARPHRD_SIT
){
383 unsigned char *p
= skb
->mac
.raw
;
384 for (i
= 0; i
< skb
->dev
->hard_header_len
; i
++,p
++)
386 i
==skb
->dev
->hard_header_len
- 1
390 unsigned char *p
= skb
->mac
.raw
;
391 if ( p
- (ETH_ALEN
*2+2) > skb
->head
){
393 for (i
= 0; i
< (ETH_ALEN
); i
++,p
++)
395 i
== ETH_ALEN
-1 ? "->" : ":");
397 for (i
= 0; i
< (ETH_ALEN
); i
++,p
++)
399 i
== ETH_ALEN
-1 ? ' ' : ':');
402 if ((skb
->dev
->addr_len
== 4) &&
403 skb
->dev
->hard_header_len
> 20){
405 p
= skb
->mac
.raw
+ 12;
406 for (i
= 0; i
< 4; i
++,p
++)
408 i
== 3 ? "->" : ".");
409 for (i
= 0; i
< 4; i
++,p
++)
418 dump_packet(loginfo
, skb
, (u8
*)skb
->nh
.ipv6h
- skb
->data
, 1);
420 spin_unlock_bh(&log_lock
);
424 ip6t_log_target(struct sk_buff
**pskb
,
425 const struct net_device
*in
,
426 const struct net_device
*out
,
427 unsigned int hooknum
,
428 const void *targinfo
,
431 const struct ip6t_log_info
*loginfo
= targinfo
;
432 char level_string
[4] = "< >";
434 level_string
[1] = '0' + (loginfo
->level
% 8);
435 ip6t_log_packet(hooknum
, *pskb
, in
, out
, loginfo
, level_string
, NULL
);
437 return IP6T_CONTINUE
;
441 ip6t_logfn(unsigned int hooknum
,
442 const struct sk_buff
*skb
,
443 const struct net_device
*in
,
444 const struct net_device
*out
,
447 struct ip6t_log_info loginfo
= {
449 .logflags
= IP6T_LOG_MASK
,
453 ip6t_log_packet(hooknum
, skb
, in
, out
, &loginfo
, KERN_WARNING
, prefix
);
456 static int ip6t_log_checkentry(const char *tablename
,
457 const struct ip6t_entry
*e
,
459 unsigned int targinfosize
,
460 unsigned int hook_mask
)
462 const struct ip6t_log_info
*loginfo
= targinfo
;
464 if (targinfosize
!= IP6T_ALIGN(sizeof(struct ip6t_log_info
))) {
465 DEBUGP("LOG: targinfosize %u != %u\n",
466 targinfosize
, IP6T_ALIGN(sizeof(struct ip6t_log_info
)));
470 if (loginfo
->level
>= 8) {
471 DEBUGP("LOG: level %u >= 8\n", loginfo
->level
);
475 if (loginfo
->prefix
[sizeof(loginfo
->prefix
)-1] != '\0') {
476 DEBUGP("LOG: prefix term %i\n",
477 loginfo
->prefix
[sizeof(loginfo
->prefix
)-1]);
484 static struct ip6t_target ip6t_log_reg
= {
486 .target
= ip6t_log_target
,
487 .checkentry
= ip6t_log_checkentry
,
491 static int __init
init(void)
493 if (ip6t_register_target(&ip6t_log_reg
))
496 nf_log_register(PF_INET6
, &ip6t_logfn
);
501 static void __exit
fini(void)
504 nf_log_unregister(PF_INET6
, &ip6t_logfn
);
505 ip6t_unregister_target(&ip6t_log_reg
);