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>
16 #include <linux/if_arp.h>
18 #include <linux/spinlock.h>
19 #include <linux/icmpv6.h>
23 #include <linux/netfilter.h>
24 #include <linux/netfilter/x_tables.h>
25 #include <linux/netfilter_ipv6/ip6_tables.h>
27 MODULE_AUTHOR("Jan Rekorajski <baggins@pld.org.pl>");
28 MODULE_DESCRIPTION("IP6 tables LOG target module");
29 MODULE_LICENSE("GPL");
32 #include <net/route.h>
33 #include <linux/netfilter_ipv6/ip6t_LOG.h>
38 #define DEBUGP(format, args...)
41 /* Use lock to serialize, so printks don't overlap */
42 static DEFINE_SPINLOCK(log_lock
);
44 /* One level of recursion won't kill us */
45 static void dump_packet(const struct nf_loginfo
*info
,
46 const struct sk_buff
*skb
, unsigned int ip6hoff
,
52 const struct ipv6hdr
*ih
;
54 unsigned int hdrlen
= 0;
55 unsigned int logflags
;
57 if (info
->type
== NF_LOG_TYPE_LOG
)
58 logflags
= info
->u
.log
.logflags
;
60 logflags
= NF_LOG_MASK
;
62 ih
= skb_header_pointer(skb
, ip6hoff
, sizeof(_ip6h
), &_ip6h
);
68 /* Max length: 88 "SRC=0000.0000.0000.0000.0000.0000.0000.0000 DST=0000.0000.0000.0000.0000.0000.0000.0000 " */
69 printk("SRC=" NIP6_FMT
" DST=" NIP6_FMT
" ", NIP6(ih
->saddr
), NIP6(ih
->daddr
));
71 /* Max length: 44 "LEN=65535 TC=255 HOPLIMIT=255 FLOWLBL=FFFFF " */
72 printk("LEN=%Zu TC=%u HOPLIMIT=%u FLOWLBL=%u ",
73 ntohs(ih
->payload_len
) + sizeof(struct ipv6hdr
),
74 (ntohl(*(__be32
*)ih
) & 0x0ff00000) >> 20,
76 (ntohl(*(__be32
*)ih
) & 0x000fffff));
79 ptr
= ip6hoff
+ sizeof(struct ipv6hdr
);
80 currenthdr
= ih
->nexthdr
;
81 while (currenthdr
!= NEXTHDR_NONE
&& ip6t_ext_hdr(currenthdr
)) {
82 struct ipv6_opt_hdr _hdr
;
83 const struct ipv6_opt_hdr
*hp
;
85 hp
= skb_header_pointer(skb
, ptr
, sizeof(_hdr
), &_hdr
);
91 /* Max length: 48 "OPT (...) " */
92 if (logflags
& IP6T_LOG_IPOPT
)
96 case IPPROTO_FRAGMENT
: {
97 struct frag_hdr _fhdr
;
98 const struct frag_hdr
*fh
;
101 fh
= skb_header_pointer(skb
, ptr
, sizeof(_fhdr
),
104 printk("TRUNCATED ");
108 /* Max length: 6 "65535 " */
109 printk("%u ", ntohs(fh
->frag_off
) & 0xFFF8);
111 /* Max length: 11 "INCOMPLETE " */
112 if (fh
->frag_off
& htons(0x0001))
113 printk("INCOMPLETE ");
115 printk("ID:%08x ", ntohl(fh
->identification
));
117 if (ntohs(fh
->frag_off
) & 0xFFF8)
124 case IPPROTO_DSTOPTS
:
125 case IPPROTO_ROUTING
:
126 case IPPROTO_HOPOPTS
:
128 if (logflags
& IP6T_LOG_IPOPT
)
132 hdrlen
= ipv6_optlen(hp
);
136 if (logflags
& IP6T_LOG_IPOPT
) {
137 struct ip_auth_hdr _ahdr
;
138 const struct ip_auth_hdr
*ah
;
140 /* Max length: 3 "AH " */
148 ah
= skb_header_pointer(skb
, ptr
, sizeof(_ahdr
),
152 * Max length: 26 "INCOMPLETE [65535
155 printk("INCOMPLETE [%u bytes] )",
160 /* Length: 15 "SPI=0xF1234567 */
161 printk("SPI=0x%x ", ntohl(ah
->spi
));
165 hdrlen
= (hp
->hdrlen
+2)<<2;
168 if (logflags
& IP6T_LOG_IPOPT
) {
169 struct ip_esp_hdr _esph
;
170 const struct ip_esp_hdr
*eh
;
172 /* Max length: 4 "ESP " */
181 * Max length: 26 "INCOMPLETE [65535 bytes] )"
183 eh
= skb_header_pointer(skb
, ptr
, sizeof(_esph
),
186 printk("INCOMPLETE [%u bytes] )",
191 /* Length: 16 "SPI=0xF1234567 )" */
192 printk("SPI=0x%x )", ntohl(eh
->spi
) );
197 /* Max length: 20 "Unknown Ext Hdr 255" */
198 printk("Unknown Ext Hdr %u", currenthdr
);
201 if (logflags
& IP6T_LOG_IPOPT
)
204 currenthdr
= hp
->nexthdr
;
208 switch (currenthdr
) {
211 const struct tcphdr
*th
;
213 /* Max length: 10 "PROTO=TCP " */
214 printk("PROTO=TCP ");
219 /* Max length: 25 "INCOMPLETE [65535 bytes] " */
220 th
= skb_header_pointer(skb
, ptr
, sizeof(_tcph
), &_tcph
);
222 printk("INCOMPLETE [%u bytes] ", skb
->len
- ptr
);
226 /* Max length: 20 "SPT=65535 DPT=65535 " */
227 printk("SPT=%u DPT=%u ",
228 ntohs(th
->source
), ntohs(th
->dest
));
229 /* Max length: 30 "SEQ=4294967295 ACK=4294967295 " */
230 if (logflags
& IP6T_LOG_TCPSEQ
)
231 printk("SEQ=%u ACK=%u ",
232 ntohl(th
->seq
), ntohl(th
->ack_seq
));
233 /* Max length: 13 "WINDOW=65535 " */
234 printk("WINDOW=%u ", ntohs(th
->window
));
235 /* Max length: 9 "RES=0x3C " */
236 printk("RES=0x%02x ", (u_int8_t
)(ntohl(tcp_flag_word(th
) & TCP_RESERVED_BITS
) >> 22));
237 /* Max length: 32 "CWR ECE URG ACK PSH RST SYN FIN " */
254 /* Max length: 11 "URGP=65535 " */
255 printk("URGP=%u ", ntohs(th
->urg_ptr
));
257 if ((logflags
& IP6T_LOG_TCPOPT
)
258 && th
->doff
* 4 > sizeof(struct tcphdr
)) {
259 u_int8_t _opt
[60 - sizeof(struct tcphdr
)];
262 unsigned int optsize
= th
->doff
* 4
263 - sizeof(struct tcphdr
);
265 op
= skb_header_pointer(skb
,
266 ptr
+ sizeof(struct tcphdr
),
269 printk("OPT (TRUNCATED)");
273 /* Max length: 127 "OPT (" 15*4*2chars ") " */
275 for (i
=0; i
< optsize
; i
++)
276 printk("%02X", op
[i
]);
282 case IPPROTO_UDPLITE
: {
284 const struct udphdr
*uh
;
286 if (currenthdr
== IPPROTO_UDP
)
287 /* Max length: 10 "PROTO=UDP " */
288 printk("PROTO=UDP " );
289 else /* Max length: 14 "PROTO=UDPLITE " */
290 printk("PROTO=UDPLITE ");
295 /* Max length: 25 "INCOMPLETE [65535 bytes] " */
296 uh
= skb_header_pointer(skb
, ptr
, sizeof(_udph
), &_udph
);
298 printk("INCOMPLETE [%u bytes] ", skb
->len
- ptr
);
302 /* Max length: 20 "SPT=65535 DPT=65535 " */
303 printk("SPT=%u DPT=%u LEN=%u ",
304 ntohs(uh
->source
), ntohs(uh
->dest
),
308 case IPPROTO_ICMPV6
: {
309 struct icmp6hdr _icmp6h
;
310 const struct icmp6hdr
*ic
;
312 /* Max length: 13 "PROTO=ICMPv6 " */
313 printk("PROTO=ICMPv6 ");
318 /* Max length: 25 "INCOMPLETE [65535 bytes] " */
319 ic
= skb_header_pointer(skb
, ptr
, sizeof(_icmp6h
), &_icmp6h
);
321 printk("INCOMPLETE [%u bytes] ", skb
->len
- ptr
);
325 /* Max length: 18 "TYPE=255 CODE=255 " */
326 printk("TYPE=%u CODE=%u ", ic
->icmp6_type
, ic
->icmp6_code
);
328 switch (ic
->icmp6_type
) {
329 case ICMPV6_ECHO_REQUEST
:
330 case ICMPV6_ECHO_REPLY
:
331 /* Max length: 19 "ID=65535 SEQ=65535 " */
332 printk("ID=%u SEQ=%u ",
333 ntohs(ic
->icmp6_identifier
),
334 ntohs(ic
->icmp6_sequence
));
336 case ICMPV6_MGM_QUERY
:
337 case ICMPV6_MGM_REPORT
:
338 case ICMPV6_MGM_REDUCTION
:
341 case ICMPV6_PARAMPROB
:
342 /* Max length: 17 "POINTER=ffffffff " */
343 printk("POINTER=%08x ", ntohl(ic
->icmp6_pointer
));
345 case ICMPV6_DEST_UNREACH
:
346 case ICMPV6_PKT_TOOBIG
:
347 case ICMPV6_TIME_EXCEED
:
348 /* Max length: 3+maxlen */
351 dump_packet(info
, skb
, ptr
+ sizeof(_icmp6h
),
356 /* Max length: 10 "MTU=65535 " */
357 if (ic
->icmp6_type
== ICMPV6_PKT_TOOBIG
)
358 printk("MTU=%u ", ntohl(ic
->icmp6_mtu
));
362 /* Max length: 10 "PROTO=255 " */
364 printk("PROTO=%u ", currenthdr
);
367 /* Max length: 15 "UID=4294967295 " */
368 if ((logflags
& IP6T_LOG_UID
) && recurse
&& skb
->sk
) {
369 read_lock_bh(&skb
->sk
->sk_callback_lock
);
370 if (skb
->sk
->sk_socket
&& skb
->sk
->sk_socket
->file
)
371 printk("UID=%u ", skb
->sk
->sk_socket
->file
->f_uid
);
372 read_unlock_bh(&skb
->sk
->sk_callback_lock
);
376 static struct nf_loginfo default_loginfo
= {
377 .type
= NF_LOG_TYPE_LOG
,
381 .logflags
= NF_LOG_MASK
,
387 ip6t_log_packet(unsigned int pf
,
388 unsigned int hooknum
,
389 const struct sk_buff
*skb
,
390 const struct net_device
*in
,
391 const struct net_device
*out
,
392 const struct nf_loginfo
*loginfo
,
396 loginfo
= &default_loginfo
;
398 spin_lock_bh(&log_lock
);
399 printk("<%d>%sIN=%s OUT=%s ", loginfo
->u
.log
.level
,
402 out
? out
->name
: "");
405 /* MAC logging for input chain only. */
407 if (skb
->dev
&& (len
= skb
->dev
->hard_header_len
) &&
408 skb
->mac_header
!= skb
->network_header
) {
409 const unsigned char *p
= skb_mac_header(skb
);
412 if (skb
->dev
->type
== ARPHRD_SIT
&&
413 (p
-= ETH_HLEN
) < skb
->head
)
417 for (i
= 0; i
< len
; i
++)
418 printk("%02x%s", p
[i
],
419 i
== len
- 1 ? "" : ":");
423 if (skb
->dev
->type
== ARPHRD_SIT
) {
424 const struct iphdr
*iph
=
425 (struct iphdr
*)skb_mac_header(skb
);
426 printk("TUNNEL=%u.%u.%u.%u->%u.%u.%u.%u ",
428 NIPQUAD(iph
->daddr
));
434 dump_packet(loginfo
, skb
, skb_network_offset(skb
), 1);
436 spin_unlock_bh(&log_lock
);
440 ip6t_log_target(struct sk_buff
**pskb
,
441 const struct net_device
*in
,
442 const struct net_device
*out
,
443 unsigned int hooknum
,
444 const struct xt_target
*target
,
445 const void *targinfo
)
447 const struct ip6t_log_info
*loginfo
= targinfo
;
448 struct nf_loginfo li
;
450 li
.type
= NF_LOG_TYPE_LOG
;
451 li
.u
.log
.level
= loginfo
->level
;
452 li
.u
.log
.logflags
= loginfo
->logflags
;
454 ip6t_log_packet(PF_INET6
, hooknum
, *pskb
, in
, out
, &li
,
460 static bool ip6t_log_checkentry(const char *tablename
,
462 const struct xt_target
*target
,
464 unsigned int hook_mask
)
466 const struct ip6t_log_info
*loginfo
= targinfo
;
468 if (loginfo
->level
>= 8) {
469 DEBUGP("LOG: level %u >= 8\n", loginfo
->level
);
472 if (loginfo
->prefix
[sizeof(loginfo
->prefix
)-1] != '\0') {
473 DEBUGP("LOG: prefix term %i\n",
474 loginfo
->prefix
[sizeof(loginfo
->prefix
)-1]);
480 static struct xt_target ip6t_log_reg
= {
483 .target
= ip6t_log_target
,
484 .targetsize
= sizeof(struct ip6t_log_info
),
485 .checkentry
= ip6t_log_checkentry
,
489 static struct nf_logger ip6t_logger
= {
491 .logfn
= &ip6t_log_packet
,
495 static int __init
ip6t_log_init(void)
499 ret
= xt_register_target(&ip6t_log_reg
);
502 ret
= nf_log_register(PF_INET6
, &ip6t_logger
);
503 if (ret
< 0 && ret
!= -EEXIST
)
504 xt_unregister_target(&ip6t_log_reg
);
508 static void __exit
ip6t_log_fini(void)
510 nf_log_unregister(&ip6t_logger
);
511 xt_unregister_target(&ip6t_log_reg
);
514 module_init(ip6t_log_init
);
515 module_exit(ip6t_log_fini
);