Commit | Line | Data |
---|---|---|
6939c33a RW |
1 | /* |
2 | * This is a module which is used for logging packets. | |
3 | */ | |
4 | ||
5 | /* (C) 1999-2001 Paul `Rusty' Russell | |
6 | * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org> | |
7 | * | |
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. | |
11 | */ | |
12 | ||
13 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt | |
14 | #include <linux/module.h> | |
15 | #include <linux/spinlock.h> | |
16 | #include <linux/skbuff.h> | |
17 | #include <linux/if_arp.h> | |
18 | #include <linux/ip.h> | |
19 | #include <net/ipv6.h> | |
20 | #include <net/icmp.h> | |
21 | #include <net/udp.h> | |
22 | #include <net/tcp.h> | |
23 | #include <net/route.h> | |
24 | ||
25 | #include <linux/netfilter.h> | |
26 | #include <linux/netfilter/x_tables.h> | |
27 | #include <linux/netfilter/xt_LOG.h> | |
28 | #include <linux/netfilter_ipv6/ip6_tables.h> | |
29 | #include <net/netfilter/nf_log.h> | |
30 | #include <net/netfilter/xt_log.h> | |
31 | ||
32 | static struct nf_loginfo default_loginfo = { | |
33 | .type = NF_LOG_TYPE_LOG, | |
34 | .u = { | |
35 | .log = { | |
36 | .level = 5, | |
37 | .logflags = NF_LOG_MASK, | |
38 | }, | |
39 | }, | |
40 | }; | |
41 | ||
42 | static int dump_udp_header(struct sbuff *m, const struct sk_buff *skb, | |
43 | u8 proto, int fragment, unsigned int offset) | |
44 | { | |
45 | struct udphdr _udph; | |
46 | const struct udphdr *uh; | |
47 | ||
48 | if (proto == IPPROTO_UDP) | |
49 | /* Max length: 10 "PROTO=UDP " */ | |
50 | sb_add(m, "PROTO=UDP "); | |
51 | else /* Max length: 14 "PROTO=UDPLITE " */ | |
52 | sb_add(m, "PROTO=UDPLITE "); | |
53 | ||
54 | if (fragment) | |
55 | goto out; | |
56 | ||
57 | /* Max length: 25 "INCOMPLETE [65535 bytes] " */ | |
58 | uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); | |
59 | if (uh == NULL) { | |
60 | sb_add(m, "INCOMPLETE [%u bytes] ", skb->len - offset); | |
61 | ||
62 | return 1; | |
63 | } | |
64 | ||
65 | /* Max length: 20 "SPT=65535 DPT=65535 " */ | |
66 | sb_add(m, "SPT=%u DPT=%u LEN=%u ", ntohs(uh->source), ntohs(uh->dest), | |
67 | ntohs(uh->len)); | |
68 | ||
69 | out: | |
70 | return 0; | |
71 | } | |
72 | ||
73 | static int dump_tcp_header(struct sbuff *m, const struct sk_buff *skb, | |
74 | u8 proto, int fragment, unsigned int offset, | |
75 | unsigned int logflags) | |
76 | { | |
77 | struct tcphdr _tcph; | |
78 | const struct tcphdr *th; | |
79 | ||
80 | /* Max length: 10 "PROTO=TCP " */ | |
81 | sb_add(m, "PROTO=TCP "); | |
82 | ||
83 | if (fragment) | |
84 | return 0; | |
85 | ||
86 | /* Max length: 25 "INCOMPLETE [65535 bytes] " */ | |
87 | th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); | |
88 | if (th == NULL) { | |
89 | sb_add(m, "INCOMPLETE [%u bytes] ", skb->len - offset); | |
90 | return 1; | |
91 | } | |
92 | ||
93 | /* Max length: 20 "SPT=65535 DPT=65535 " */ | |
94 | sb_add(m, "SPT=%u DPT=%u ", ntohs(th->source), ntohs(th->dest)); | |
95 | /* Max length: 30 "SEQ=4294967295 ACK=4294967295 " */ | |
96 | if (logflags & XT_LOG_TCPSEQ) | |
97 | sb_add(m, "SEQ=%u ACK=%u ", ntohl(th->seq), ntohl(th->ack_seq)); | |
98 | ||
99 | /* Max length: 13 "WINDOW=65535 " */ | |
100 | sb_add(m, "WINDOW=%u ", ntohs(th->window)); | |
101 | /* Max length: 9 "RES=0x3C " */ | |
102 | sb_add(m, "RES=0x%02x ", (u_int8_t)(ntohl(tcp_flag_word(th) & | |
103 | TCP_RESERVED_BITS) >> 22)); | |
104 | /* Max length: 32 "CWR ECE URG ACK PSH RST SYN FIN " */ | |
105 | if (th->cwr) | |
106 | sb_add(m, "CWR "); | |
107 | if (th->ece) | |
108 | sb_add(m, "ECE "); | |
109 | if (th->urg) | |
110 | sb_add(m, "URG "); | |
111 | if (th->ack) | |
112 | sb_add(m, "ACK "); | |
113 | if (th->psh) | |
114 | sb_add(m, "PSH "); | |
115 | if (th->rst) | |
116 | sb_add(m, "RST "); | |
117 | if (th->syn) | |
118 | sb_add(m, "SYN "); | |
119 | if (th->fin) | |
120 | sb_add(m, "FIN "); | |
121 | /* Max length: 11 "URGP=65535 " */ | |
122 | sb_add(m, "URGP=%u ", ntohs(th->urg_ptr)); | |
123 | ||
124 | if ((logflags & XT_LOG_TCPOPT) && th->doff*4 > sizeof(struct tcphdr)) { | |
125 | u_int8_t _opt[60 - sizeof(struct tcphdr)]; | |
126 | const u_int8_t *op; | |
127 | unsigned int i; | |
128 | unsigned int optsize = th->doff*4 - sizeof(struct tcphdr); | |
129 | ||
130 | op = skb_header_pointer(skb, offset + sizeof(struct tcphdr), | |
131 | optsize, _opt); | |
132 | if (op == NULL) { | |
133 | sb_add(m, "OPT (TRUNCATED)"); | |
134 | return 1; | |
135 | } | |
136 | ||
137 | /* Max length: 127 "OPT (" 15*4*2chars ") " */ | |
138 | sb_add(m, "OPT ("); | |
139 | for (i = 0; i < optsize; i++) | |
140 | sb_add(m, "%02X", op[i]); | |
141 | ||
142 | sb_add(m, ") "); | |
143 | } | |
144 | ||
145 | return 0; | |
146 | } | |
147 | ||
0626af31 ED |
148 | static void dump_sk_uid_gid(struct sbuff *m, struct sock *sk) |
149 | { | |
150 | if (!sk || sk->sk_state == TCP_TIME_WAIT) | |
151 | return; | |
152 | ||
153 | read_lock_bh(&sk->sk_callback_lock); | |
437589a7 LT |
154 | if (sk->sk_socket && sk->sk_socket->file) { |
155 | const struct cred *cred = sk->sk_socket->file->f_cred; | |
0626af31 | 156 | sb_add(m, "UID=%u GID=%u ", |
437589a7 LT |
157 | from_kuid_munged(&init_user_ns, cred->fsuid), |
158 | from_kgid_munged(&init_user_ns, cred->fsgid)); | |
159 | } | |
0626af31 ED |
160 | read_unlock_bh(&sk->sk_callback_lock); |
161 | } | |
162 | ||
6939c33a RW |
163 | /* One level of recursion won't kill us */ |
164 | static void dump_ipv4_packet(struct sbuff *m, | |
165 | const struct nf_loginfo *info, | |
166 | const struct sk_buff *skb, | |
167 | unsigned int iphoff) | |
168 | { | |
169 | struct iphdr _iph; | |
170 | const struct iphdr *ih; | |
171 | unsigned int logflags; | |
172 | ||
173 | if (info->type == NF_LOG_TYPE_LOG) | |
174 | logflags = info->u.log.logflags; | |
175 | else | |
176 | logflags = NF_LOG_MASK; | |
177 | ||
178 | ih = skb_header_pointer(skb, iphoff, sizeof(_iph), &_iph); | |
179 | if (ih == NULL) { | |
180 | sb_add(m, "TRUNCATED"); | |
181 | return; | |
182 | } | |
183 | ||
184 | /* Important fields: | |
185 | * TOS, len, DF/MF, fragment offset, TTL, src, dst, options. */ | |
186 | /* Max length: 40 "SRC=255.255.255.255 DST=255.255.255.255 " */ | |
187 | sb_add(m, "SRC=%pI4 DST=%pI4 ", | |
188 | &ih->saddr, &ih->daddr); | |
189 | ||
190 | /* Max length: 46 "LEN=65535 TOS=0xFF PREC=0xFF TTL=255 ID=65535 " */ | |
191 | sb_add(m, "LEN=%u TOS=0x%02X PREC=0x%02X TTL=%u ID=%u ", | |
192 | ntohs(ih->tot_len), ih->tos & IPTOS_TOS_MASK, | |
193 | ih->tos & IPTOS_PREC_MASK, ih->ttl, ntohs(ih->id)); | |
194 | ||
195 | /* Max length: 6 "CE DF MF " */ | |
196 | if (ntohs(ih->frag_off) & IP_CE) | |
197 | sb_add(m, "CE "); | |
198 | if (ntohs(ih->frag_off) & IP_DF) | |
199 | sb_add(m, "DF "); | |
200 | if (ntohs(ih->frag_off) & IP_MF) | |
201 | sb_add(m, "MF "); | |
202 | ||
203 | /* Max length: 11 "FRAG:65535 " */ | |
204 | if (ntohs(ih->frag_off) & IP_OFFSET) | |
205 | sb_add(m, "FRAG:%u ", ntohs(ih->frag_off) & IP_OFFSET); | |
206 | ||
207 | if ((logflags & XT_LOG_IPOPT) && | |
208 | ih->ihl * 4 > sizeof(struct iphdr)) { | |
209 | const unsigned char *op; | |
210 | unsigned char _opt[4 * 15 - sizeof(struct iphdr)]; | |
211 | unsigned int i, optsize; | |
212 | ||
213 | optsize = ih->ihl * 4 - sizeof(struct iphdr); | |
214 | op = skb_header_pointer(skb, iphoff+sizeof(_iph), | |
215 | optsize, _opt); | |
216 | if (op == NULL) { | |
217 | sb_add(m, "TRUNCATED"); | |
218 | return; | |
219 | } | |
220 | ||
221 | /* Max length: 127 "OPT (" 15*4*2chars ") " */ | |
222 | sb_add(m, "OPT ("); | |
223 | for (i = 0; i < optsize; i++) | |
224 | sb_add(m, "%02X", op[i]); | |
225 | sb_add(m, ") "); | |
226 | } | |
227 | ||
228 | switch (ih->protocol) { | |
229 | case IPPROTO_TCP: | |
230 | if (dump_tcp_header(m, skb, ih->protocol, | |
231 | ntohs(ih->frag_off) & IP_OFFSET, | |
232 | iphoff+ih->ihl*4, logflags)) | |
233 | return; | |
417e02bf | 234 | break; |
6939c33a RW |
235 | case IPPROTO_UDP: |
236 | case IPPROTO_UDPLITE: | |
237 | if (dump_udp_header(m, skb, ih->protocol, | |
238 | ntohs(ih->frag_off) & IP_OFFSET, | |
239 | iphoff+ih->ihl*4)) | |
240 | return; | |
417e02bf | 241 | break; |
6939c33a RW |
242 | case IPPROTO_ICMP: { |
243 | struct icmphdr _icmph; | |
244 | const struct icmphdr *ich; | |
245 | static const size_t required_len[NR_ICMP_TYPES+1] | |
246 | = { [ICMP_ECHOREPLY] = 4, | |
247 | [ICMP_DEST_UNREACH] | |
248 | = 8 + sizeof(struct iphdr), | |
249 | [ICMP_SOURCE_QUENCH] | |
250 | = 8 + sizeof(struct iphdr), | |
251 | [ICMP_REDIRECT] | |
252 | = 8 + sizeof(struct iphdr), | |
253 | [ICMP_ECHO] = 4, | |
254 | [ICMP_TIME_EXCEEDED] | |
255 | = 8 + sizeof(struct iphdr), | |
256 | [ICMP_PARAMETERPROB] | |
257 | = 8 + sizeof(struct iphdr), | |
258 | [ICMP_TIMESTAMP] = 20, | |
259 | [ICMP_TIMESTAMPREPLY] = 20, | |
260 | [ICMP_ADDRESS] = 12, | |
261 | [ICMP_ADDRESSREPLY] = 12 }; | |
262 | ||
263 | /* Max length: 11 "PROTO=ICMP " */ | |
264 | sb_add(m, "PROTO=ICMP "); | |
265 | ||
266 | if (ntohs(ih->frag_off) & IP_OFFSET) | |
267 | break; | |
268 | ||
269 | /* Max length: 25 "INCOMPLETE [65535 bytes] " */ | |
270 | ich = skb_header_pointer(skb, iphoff + ih->ihl * 4, | |
271 | sizeof(_icmph), &_icmph); | |
272 | if (ich == NULL) { | |
273 | sb_add(m, "INCOMPLETE [%u bytes] ", | |
274 | skb->len - iphoff - ih->ihl*4); | |
275 | break; | |
276 | } | |
277 | ||
278 | /* Max length: 18 "TYPE=255 CODE=255 " */ | |
279 | sb_add(m, "TYPE=%u CODE=%u ", ich->type, ich->code); | |
280 | ||
281 | /* Max length: 25 "INCOMPLETE [65535 bytes] " */ | |
282 | if (ich->type <= NR_ICMP_TYPES && | |
283 | required_len[ich->type] && | |
284 | skb->len-iphoff-ih->ihl*4 < required_len[ich->type]) { | |
285 | sb_add(m, "INCOMPLETE [%u bytes] ", | |
286 | skb->len - iphoff - ih->ihl*4); | |
287 | break; | |
288 | } | |
289 | ||
290 | switch (ich->type) { | |
291 | case ICMP_ECHOREPLY: | |
292 | case ICMP_ECHO: | |
293 | /* Max length: 19 "ID=65535 SEQ=65535 " */ | |
294 | sb_add(m, "ID=%u SEQ=%u ", | |
295 | ntohs(ich->un.echo.id), | |
296 | ntohs(ich->un.echo.sequence)); | |
297 | break; | |
298 | ||
299 | case ICMP_PARAMETERPROB: | |
300 | /* Max length: 14 "PARAMETER=255 " */ | |
301 | sb_add(m, "PARAMETER=%u ", | |
302 | ntohl(ich->un.gateway) >> 24); | |
303 | break; | |
304 | case ICMP_REDIRECT: | |
305 | /* Max length: 24 "GATEWAY=255.255.255.255 " */ | |
306 | sb_add(m, "GATEWAY=%pI4 ", &ich->un.gateway); | |
307 | /* Fall through */ | |
308 | case ICMP_DEST_UNREACH: | |
309 | case ICMP_SOURCE_QUENCH: | |
310 | case ICMP_TIME_EXCEEDED: | |
311 | /* Max length: 3+maxlen */ | |
312 | if (!iphoff) { /* Only recurse once. */ | |
313 | sb_add(m, "["); | |
314 | dump_ipv4_packet(m, info, skb, | |
315 | iphoff + ih->ihl*4+sizeof(_icmph)); | |
316 | sb_add(m, "] "); | |
317 | } | |
318 | ||
319 | /* Max length: 10 "MTU=65535 " */ | |
320 | if (ich->type == ICMP_DEST_UNREACH && | |
321 | ich->code == ICMP_FRAG_NEEDED) | |
322 | sb_add(m, "MTU=%u ", ntohs(ich->un.frag.mtu)); | |
323 | } | |
324 | break; | |
325 | } | |
326 | /* Max Length */ | |
327 | case IPPROTO_AH: { | |
328 | struct ip_auth_hdr _ahdr; | |
329 | const struct ip_auth_hdr *ah; | |
330 | ||
331 | if (ntohs(ih->frag_off) & IP_OFFSET) | |
332 | break; | |
333 | ||
334 | /* Max length: 9 "PROTO=AH " */ | |
335 | sb_add(m, "PROTO=AH "); | |
336 | ||
337 | /* Max length: 25 "INCOMPLETE [65535 bytes] " */ | |
338 | ah = skb_header_pointer(skb, iphoff+ih->ihl*4, | |
339 | sizeof(_ahdr), &_ahdr); | |
340 | if (ah == NULL) { | |
341 | sb_add(m, "INCOMPLETE [%u bytes] ", | |
342 | skb->len - iphoff - ih->ihl*4); | |
343 | break; | |
344 | } | |
345 | ||
346 | /* Length: 15 "SPI=0xF1234567 " */ | |
347 | sb_add(m, "SPI=0x%x ", ntohl(ah->spi)); | |
348 | break; | |
349 | } | |
350 | case IPPROTO_ESP: { | |
351 | struct ip_esp_hdr _esph; | |
352 | const struct ip_esp_hdr *eh; | |
353 | ||
354 | /* Max length: 10 "PROTO=ESP " */ | |
355 | sb_add(m, "PROTO=ESP "); | |
356 | ||
357 | if (ntohs(ih->frag_off) & IP_OFFSET) | |
358 | break; | |
359 | ||
360 | /* Max length: 25 "INCOMPLETE [65535 bytes] " */ | |
361 | eh = skb_header_pointer(skb, iphoff+ih->ihl*4, | |
362 | sizeof(_esph), &_esph); | |
363 | if (eh == NULL) { | |
364 | sb_add(m, "INCOMPLETE [%u bytes] ", | |
365 | skb->len - iphoff - ih->ihl*4); | |
366 | break; | |
367 | } | |
368 | ||
369 | /* Length: 15 "SPI=0xF1234567 " */ | |
370 | sb_add(m, "SPI=0x%x ", ntohl(eh->spi)); | |
371 | break; | |
372 | } | |
373 | /* Max length: 10 "PROTO 255 " */ | |
374 | default: | |
375 | sb_add(m, "PROTO=%u ", ih->protocol); | |
376 | } | |
377 | ||
378 | /* Max length: 15 "UID=4294967295 " */ | |
0626af31 ED |
379 | if ((logflags & XT_LOG_UID) && !iphoff) |
380 | dump_sk_uid_gid(m, skb->sk); | |
6939c33a RW |
381 | |
382 | /* Max length: 16 "MARK=0xFFFFFFFF " */ | |
383 | if (!iphoff && skb->mark) | |
384 | sb_add(m, "MARK=0x%x ", skb->mark); | |
385 | ||
386 | /* Proto Max log string length */ | |
387 | /* IP: 40+46+6+11+127 = 230 */ | |
388 | /* TCP: 10+max(25,20+30+13+9+32+11+127) = 252 */ | |
389 | /* UDP: 10+max(25,20) = 35 */ | |
390 | /* UDPLITE: 14+max(25,20) = 39 */ | |
391 | /* ICMP: 11+max(25, 18+25+max(19,14,24+3+n+10,3+n+10)) = 91+n */ | |
392 | /* ESP: 10+max(25)+15 = 50 */ | |
393 | /* AH: 9+max(25)+15 = 49 */ | |
394 | /* unknown: 10 */ | |
395 | ||
396 | /* (ICMP allows recursion one level deep) */ | |
397 | /* maxlen = IP + ICMP + IP + max(TCP,UDP,ICMP,unknown) */ | |
398 | /* maxlen = 230+ 91 + 230 + 252 = 803 */ | |
399 | } | |
400 | ||
401 | static void dump_ipv4_mac_header(struct sbuff *m, | |
402 | const struct nf_loginfo *info, | |
403 | const struct sk_buff *skb) | |
404 | { | |
405 | struct net_device *dev = skb->dev; | |
406 | unsigned int logflags = 0; | |
407 | ||
408 | if (info->type == NF_LOG_TYPE_LOG) | |
409 | logflags = info->u.log.logflags; | |
410 | ||
411 | if (!(logflags & XT_LOG_MACDECODE)) | |
412 | goto fallback; | |
413 | ||
414 | switch (dev->type) { | |
415 | case ARPHRD_ETHER: | |
416 | sb_add(m, "MACSRC=%pM MACDST=%pM MACPROTO=%04x ", | |
417 | eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest, | |
418 | ntohs(eth_hdr(skb)->h_proto)); | |
419 | return; | |
420 | default: | |
421 | break; | |
422 | } | |
423 | ||
424 | fallback: | |
425 | sb_add(m, "MAC="); | |
426 | if (dev->hard_header_len && | |
427 | skb->mac_header != skb->network_header) { | |
428 | const unsigned char *p = skb_mac_header(skb); | |
429 | unsigned int i; | |
430 | ||
431 | sb_add(m, "%02x", *p++); | |
432 | for (i = 1; i < dev->hard_header_len; i++, p++) | |
433 | sb_add(m, ":%02x", *p); | |
434 | } | |
435 | sb_add(m, " "); | |
436 | } | |
437 | ||
438 | static void | |
439 | log_packet_common(struct sbuff *m, | |
440 | u_int8_t pf, | |
441 | unsigned int hooknum, | |
442 | const struct sk_buff *skb, | |
443 | const struct net_device *in, | |
444 | const struct net_device *out, | |
445 | const struct nf_loginfo *loginfo, | |
446 | const char *prefix) | |
447 | { | |
16af511a JP |
448 | sb_add(m, KERN_SOH "%c%sIN=%s OUT=%s ", |
449 | '0' + loginfo->u.log.level, prefix, | |
6939c33a RW |
450 | in ? in->name : "", |
451 | out ? out->name : ""); | |
452 | #ifdef CONFIG_BRIDGE_NETFILTER | |
453 | if (skb->nf_bridge) { | |
454 | const struct net_device *physindev; | |
455 | const struct net_device *physoutdev; | |
456 | ||
457 | physindev = skb->nf_bridge->physindev; | |
458 | if (physindev && in != physindev) | |
459 | sb_add(m, "PHYSIN=%s ", physindev->name); | |
460 | physoutdev = skb->nf_bridge->physoutdev; | |
461 | if (physoutdev && out != physoutdev) | |
462 | sb_add(m, "PHYSOUT=%s ", physoutdev->name); | |
463 | } | |
464 | #endif | |
465 | } | |
466 | ||
467 | ||
468 | static void | |
469 | ipt_log_packet(u_int8_t pf, | |
470 | unsigned int hooknum, | |
471 | const struct sk_buff *skb, | |
472 | const struct net_device *in, | |
473 | const struct net_device *out, | |
474 | const struct nf_loginfo *loginfo, | |
475 | const char *prefix) | |
476 | { | |
477 | struct sbuff *m = sb_open(); | |
478 | ||
479 | if (!loginfo) | |
480 | loginfo = &default_loginfo; | |
481 | ||
482 | log_packet_common(m, pf, hooknum, skb, in, out, loginfo, prefix); | |
483 | ||
484 | if (in != NULL) | |
485 | dump_ipv4_mac_header(m, loginfo, skb); | |
486 | ||
487 | dump_ipv4_packet(m, loginfo, skb, 0); | |
488 | ||
489 | sb_close(m); | |
490 | } | |
491 | ||
a0f65a26 | 492 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
6939c33a RW |
493 | /* One level of recursion won't kill us */ |
494 | static void dump_ipv6_packet(struct sbuff *m, | |
495 | const struct nf_loginfo *info, | |
496 | const struct sk_buff *skb, unsigned int ip6hoff, | |
497 | int recurse) | |
498 | { | |
499 | u_int8_t currenthdr; | |
500 | int fragment; | |
501 | struct ipv6hdr _ip6h; | |
502 | const struct ipv6hdr *ih; | |
503 | unsigned int ptr; | |
504 | unsigned int hdrlen = 0; | |
505 | unsigned int logflags; | |
506 | ||
507 | if (info->type == NF_LOG_TYPE_LOG) | |
508 | logflags = info->u.log.logflags; | |
509 | else | |
510 | logflags = NF_LOG_MASK; | |
511 | ||
512 | ih = skb_header_pointer(skb, ip6hoff, sizeof(_ip6h), &_ip6h); | |
513 | if (ih == NULL) { | |
514 | sb_add(m, "TRUNCATED"); | |
515 | return; | |
516 | } | |
517 | ||
518 | /* Max length: 88 "SRC=0000.0000.0000.0000.0000.0000.0000.0000 DST=0000.0000.0000.0000.0000.0000.0000.0000 " */ | |
519 | sb_add(m, "SRC=%pI6 DST=%pI6 ", &ih->saddr, &ih->daddr); | |
520 | ||
521 | /* Max length: 44 "LEN=65535 TC=255 HOPLIMIT=255 FLOWLBL=FFFFF " */ | |
522 | sb_add(m, "LEN=%Zu TC=%u HOPLIMIT=%u FLOWLBL=%u ", | |
523 | ntohs(ih->payload_len) + sizeof(struct ipv6hdr), | |
524 | (ntohl(*(__be32 *)ih) & 0x0ff00000) >> 20, | |
525 | ih->hop_limit, | |
526 | (ntohl(*(__be32 *)ih) & 0x000fffff)); | |
527 | ||
528 | fragment = 0; | |
529 | ptr = ip6hoff + sizeof(struct ipv6hdr); | |
530 | currenthdr = ih->nexthdr; | |
531 | while (currenthdr != NEXTHDR_NONE && ip6t_ext_hdr(currenthdr)) { | |
532 | struct ipv6_opt_hdr _hdr; | |
533 | const struct ipv6_opt_hdr *hp; | |
534 | ||
535 | hp = skb_header_pointer(skb, ptr, sizeof(_hdr), &_hdr); | |
536 | if (hp == NULL) { | |
537 | sb_add(m, "TRUNCATED"); | |
538 | return; | |
539 | } | |
540 | ||
541 | /* Max length: 48 "OPT (...) " */ | |
542 | if (logflags & XT_LOG_IPOPT) | |
543 | sb_add(m, "OPT ( "); | |
544 | ||
545 | switch (currenthdr) { | |
546 | case IPPROTO_FRAGMENT: { | |
547 | struct frag_hdr _fhdr; | |
548 | const struct frag_hdr *fh; | |
549 | ||
550 | sb_add(m, "FRAG:"); | |
551 | fh = skb_header_pointer(skb, ptr, sizeof(_fhdr), | |
552 | &_fhdr); | |
553 | if (fh == NULL) { | |
554 | sb_add(m, "TRUNCATED "); | |
555 | return; | |
556 | } | |
557 | ||
558 | /* Max length: 6 "65535 " */ | |
559 | sb_add(m, "%u ", ntohs(fh->frag_off) & 0xFFF8); | |
560 | ||
561 | /* Max length: 11 "INCOMPLETE " */ | |
562 | if (fh->frag_off & htons(0x0001)) | |
563 | sb_add(m, "INCOMPLETE "); | |
564 | ||
565 | sb_add(m, "ID:%08x ", ntohl(fh->identification)); | |
566 | ||
567 | if (ntohs(fh->frag_off) & 0xFFF8) | |
568 | fragment = 1; | |
569 | ||
570 | hdrlen = 8; | |
571 | ||
572 | break; | |
573 | } | |
574 | case IPPROTO_DSTOPTS: | |
575 | case IPPROTO_ROUTING: | |
576 | case IPPROTO_HOPOPTS: | |
577 | if (fragment) { | |
578 | if (logflags & XT_LOG_IPOPT) | |
579 | sb_add(m, ")"); | |
580 | return; | |
581 | } | |
582 | hdrlen = ipv6_optlen(hp); | |
583 | break; | |
584 | /* Max Length */ | |
585 | case IPPROTO_AH: | |
586 | if (logflags & XT_LOG_IPOPT) { | |
587 | struct ip_auth_hdr _ahdr; | |
588 | const struct ip_auth_hdr *ah; | |
589 | ||
590 | /* Max length: 3 "AH " */ | |
591 | sb_add(m, "AH "); | |
592 | ||
593 | if (fragment) { | |
594 | sb_add(m, ")"); | |
595 | return; | |
596 | } | |
597 | ||
598 | ah = skb_header_pointer(skb, ptr, sizeof(_ahdr), | |
599 | &_ahdr); | |
600 | if (ah == NULL) { | |
601 | /* | |
602 | * Max length: 26 "INCOMPLETE [65535 | |
603 | * bytes] )" | |
604 | */ | |
605 | sb_add(m, "INCOMPLETE [%u bytes] )", | |
606 | skb->len - ptr); | |
607 | return; | |
608 | } | |
609 | ||
610 | /* Length: 15 "SPI=0xF1234567 */ | |
611 | sb_add(m, "SPI=0x%x ", ntohl(ah->spi)); | |
612 | ||
613 | } | |
614 | ||
615 | hdrlen = (hp->hdrlen+2)<<2; | |
616 | break; | |
617 | case IPPROTO_ESP: | |
618 | if (logflags & XT_LOG_IPOPT) { | |
619 | struct ip_esp_hdr _esph; | |
620 | const struct ip_esp_hdr *eh; | |
621 | ||
622 | /* Max length: 4 "ESP " */ | |
623 | sb_add(m, "ESP "); | |
624 | ||
625 | if (fragment) { | |
626 | sb_add(m, ")"); | |
627 | return; | |
628 | } | |
629 | ||
630 | /* | |
631 | * Max length: 26 "INCOMPLETE [65535 bytes] )" | |
632 | */ | |
633 | eh = skb_header_pointer(skb, ptr, sizeof(_esph), | |
634 | &_esph); | |
635 | if (eh == NULL) { | |
636 | sb_add(m, "INCOMPLETE [%u bytes] )", | |
637 | skb->len - ptr); | |
638 | return; | |
639 | } | |
640 | ||
641 | /* Length: 16 "SPI=0xF1234567 )" */ | |
642 | sb_add(m, "SPI=0x%x )", ntohl(eh->spi)); | |
643 | ||
644 | } | |
645 | return; | |
646 | default: | |
647 | /* Max length: 20 "Unknown Ext Hdr 255" */ | |
648 | sb_add(m, "Unknown Ext Hdr %u", currenthdr); | |
649 | return; | |
650 | } | |
651 | if (logflags & XT_LOG_IPOPT) | |
652 | sb_add(m, ") "); | |
653 | ||
654 | currenthdr = hp->nexthdr; | |
655 | ptr += hdrlen; | |
656 | } | |
657 | ||
658 | switch (currenthdr) { | |
659 | case IPPROTO_TCP: | |
660 | if (dump_tcp_header(m, skb, currenthdr, fragment, ptr, | |
661 | logflags)) | |
662 | return; | |
417e02bf | 663 | break; |
6939c33a RW |
664 | case IPPROTO_UDP: |
665 | case IPPROTO_UDPLITE: | |
666 | if (dump_udp_header(m, skb, currenthdr, fragment, ptr)) | |
667 | return; | |
417e02bf | 668 | break; |
6939c33a RW |
669 | case IPPROTO_ICMPV6: { |
670 | struct icmp6hdr _icmp6h; | |
671 | const struct icmp6hdr *ic; | |
672 | ||
673 | /* Max length: 13 "PROTO=ICMPv6 " */ | |
674 | sb_add(m, "PROTO=ICMPv6 "); | |
675 | ||
676 | if (fragment) | |
677 | break; | |
678 | ||
679 | /* Max length: 25 "INCOMPLETE [65535 bytes] " */ | |
680 | ic = skb_header_pointer(skb, ptr, sizeof(_icmp6h), &_icmp6h); | |
681 | if (ic == NULL) { | |
682 | sb_add(m, "INCOMPLETE [%u bytes] ", skb->len - ptr); | |
683 | return; | |
684 | } | |
685 | ||
686 | /* Max length: 18 "TYPE=255 CODE=255 " */ | |
687 | sb_add(m, "TYPE=%u CODE=%u ", ic->icmp6_type, ic->icmp6_code); | |
688 | ||
689 | switch (ic->icmp6_type) { | |
690 | case ICMPV6_ECHO_REQUEST: | |
691 | case ICMPV6_ECHO_REPLY: | |
692 | /* Max length: 19 "ID=65535 SEQ=65535 " */ | |
693 | sb_add(m, "ID=%u SEQ=%u ", | |
694 | ntohs(ic->icmp6_identifier), | |
695 | ntohs(ic->icmp6_sequence)); | |
696 | break; | |
697 | case ICMPV6_MGM_QUERY: | |
698 | case ICMPV6_MGM_REPORT: | |
699 | case ICMPV6_MGM_REDUCTION: | |
700 | break; | |
701 | ||
702 | case ICMPV6_PARAMPROB: | |
703 | /* Max length: 17 "POINTER=ffffffff " */ | |
704 | sb_add(m, "POINTER=%08x ", ntohl(ic->icmp6_pointer)); | |
705 | /* Fall through */ | |
706 | case ICMPV6_DEST_UNREACH: | |
707 | case ICMPV6_PKT_TOOBIG: | |
708 | case ICMPV6_TIME_EXCEED: | |
709 | /* Max length: 3+maxlen */ | |
710 | if (recurse) { | |
711 | sb_add(m, "["); | |
712 | dump_ipv6_packet(m, info, skb, | |
713 | ptr + sizeof(_icmp6h), 0); | |
714 | sb_add(m, "] "); | |
715 | } | |
716 | ||
717 | /* Max length: 10 "MTU=65535 " */ | |
718 | if (ic->icmp6_type == ICMPV6_PKT_TOOBIG) | |
719 | sb_add(m, "MTU=%u ", ntohl(ic->icmp6_mtu)); | |
720 | } | |
721 | break; | |
722 | } | |
723 | /* Max length: 10 "PROTO=255 " */ | |
724 | default: | |
725 | sb_add(m, "PROTO=%u ", currenthdr); | |
726 | } | |
727 | ||
728 | /* Max length: 15 "UID=4294967295 " */ | |
0626af31 ED |
729 | if ((logflags & XT_LOG_UID) && recurse) |
730 | dump_sk_uid_gid(m, skb->sk); | |
6939c33a RW |
731 | |
732 | /* Max length: 16 "MARK=0xFFFFFFFF " */ | |
733 | if (!recurse && skb->mark) | |
734 | sb_add(m, "MARK=0x%x ", skb->mark); | |
735 | } | |
736 | ||
737 | static void dump_ipv6_mac_header(struct sbuff *m, | |
738 | const struct nf_loginfo *info, | |
739 | const struct sk_buff *skb) | |
740 | { | |
741 | struct net_device *dev = skb->dev; | |
742 | unsigned int logflags = 0; | |
743 | ||
744 | if (info->type == NF_LOG_TYPE_LOG) | |
745 | logflags = info->u.log.logflags; | |
746 | ||
747 | if (!(logflags & XT_LOG_MACDECODE)) | |
748 | goto fallback; | |
749 | ||
750 | switch (dev->type) { | |
751 | case ARPHRD_ETHER: | |
752 | sb_add(m, "MACSRC=%pM MACDST=%pM MACPROTO=%04x ", | |
753 | eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest, | |
754 | ntohs(eth_hdr(skb)->h_proto)); | |
755 | return; | |
756 | default: | |
757 | break; | |
758 | } | |
759 | ||
760 | fallback: | |
761 | sb_add(m, "MAC="); | |
762 | if (dev->hard_header_len && | |
763 | skb->mac_header != skb->network_header) { | |
764 | const unsigned char *p = skb_mac_header(skb); | |
765 | unsigned int len = dev->hard_header_len; | |
766 | unsigned int i; | |
767 | ||
768 | if (dev->type == ARPHRD_SIT) { | |
769 | p -= ETH_HLEN; | |
770 | ||
771 | if (p < skb->head) | |
772 | p = NULL; | |
773 | } | |
774 | ||
775 | if (p != NULL) { | |
776 | sb_add(m, "%02x", *p++); | |
777 | for (i = 1; i < len; i++) | |
778 | sb_add(m, ":%02x", *p++); | |
779 | } | |
780 | sb_add(m, " "); | |
781 | ||
782 | if (dev->type == ARPHRD_SIT) { | |
783 | const struct iphdr *iph = | |
784 | (struct iphdr *)skb_mac_header(skb); | |
785 | sb_add(m, "TUNNEL=%pI4->%pI4 ", &iph->saddr, | |
786 | &iph->daddr); | |
787 | } | |
788 | } else | |
789 | sb_add(m, " "); | |
790 | } | |
791 | ||
792 | static void | |
793 | ip6t_log_packet(u_int8_t pf, | |
794 | unsigned int hooknum, | |
795 | const struct sk_buff *skb, | |
796 | const struct net_device *in, | |
797 | const struct net_device *out, | |
798 | const struct nf_loginfo *loginfo, | |
799 | const char *prefix) | |
800 | { | |
801 | struct sbuff *m = sb_open(); | |
802 | ||
803 | if (!loginfo) | |
804 | loginfo = &default_loginfo; | |
805 | ||
806 | log_packet_common(m, pf, hooknum, skb, in, out, loginfo, prefix); | |
807 | ||
808 | if (in != NULL) | |
809 | dump_ipv6_mac_header(m, loginfo, skb); | |
810 | ||
811 | dump_ipv6_packet(m, loginfo, skb, skb_network_offset(skb), 1); | |
812 | ||
813 | sb_close(m); | |
814 | } | |
815 | #endif | |
816 | ||
817 | static unsigned int | |
818 | log_tg(struct sk_buff *skb, const struct xt_action_param *par) | |
819 | { | |
820 | const struct xt_log_info *loginfo = par->targinfo; | |
821 | struct nf_loginfo li; | |
822 | ||
823 | li.type = NF_LOG_TYPE_LOG; | |
824 | li.u.log.level = loginfo->level; | |
825 | li.u.log.logflags = loginfo->logflags; | |
826 | ||
827 | if (par->family == NFPROTO_IPV4) | |
828 | ipt_log_packet(NFPROTO_IPV4, par->hooknum, skb, par->in, | |
829 | par->out, &li, loginfo->prefix); | |
a0f65a26 | 830 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
6939c33a RW |
831 | else if (par->family == NFPROTO_IPV6) |
832 | ip6t_log_packet(NFPROTO_IPV6, par->hooknum, skb, par->in, | |
833 | par->out, &li, loginfo->prefix); | |
834 | #endif | |
835 | else | |
836 | WARN_ON_ONCE(1); | |
837 | ||
838 | return XT_CONTINUE; | |
839 | } | |
840 | ||
841 | static int log_tg_check(const struct xt_tgchk_param *par) | |
842 | { | |
843 | const struct xt_log_info *loginfo = par->targinfo; | |
844 | ||
845 | if (par->family != NFPROTO_IPV4 && par->family != NFPROTO_IPV6) | |
846 | return -EINVAL; | |
847 | ||
848 | if (loginfo->level >= 8) { | |
849 | pr_debug("level %u >= 8\n", loginfo->level); | |
850 | return -EINVAL; | |
851 | } | |
852 | ||
853 | if (loginfo->prefix[sizeof(loginfo->prefix)-1] != '\0') { | |
854 | pr_debug("prefix is not null-terminated\n"); | |
855 | return -EINVAL; | |
856 | } | |
857 | ||
858 | return 0; | |
859 | } | |
860 | ||
861 | static struct xt_target log_tg_regs[] __read_mostly = { | |
862 | { | |
863 | .name = "LOG", | |
864 | .family = NFPROTO_IPV4, | |
865 | .target = log_tg, | |
866 | .targetsize = sizeof(struct xt_log_info), | |
867 | .checkentry = log_tg_check, | |
868 | .me = THIS_MODULE, | |
869 | }, | |
a0f65a26 | 870 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
6939c33a RW |
871 | { |
872 | .name = "LOG", | |
873 | .family = NFPROTO_IPV6, | |
874 | .target = log_tg, | |
875 | .targetsize = sizeof(struct xt_log_info), | |
876 | .checkentry = log_tg_check, | |
877 | .me = THIS_MODULE, | |
878 | }, | |
879 | #endif | |
880 | }; | |
881 | ||
882 | static struct nf_logger ipt_log_logger __read_mostly = { | |
883 | .name = "ipt_LOG", | |
884 | .logfn = &ipt_log_packet, | |
885 | .me = THIS_MODULE, | |
886 | }; | |
887 | ||
a0f65a26 | 888 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
6939c33a RW |
889 | static struct nf_logger ip6t_log_logger __read_mostly = { |
890 | .name = "ip6t_LOG", | |
891 | .logfn = &ip6t_log_packet, | |
892 | .me = THIS_MODULE, | |
893 | }; | |
894 | #endif | |
895 | ||
896 | static int __init log_tg_init(void) | |
897 | { | |
898 | int ret; | |
899 | ||
900 | ret = xt_register_targets(log_tg_regs, ARRAY_SIZE(log_tg_regs)); | |
901 | if (ret < 0) | |
902 | return ret; | |
903 | ||
904 | nf_log_register(NFPROTO_IPV4, &ipt_log_logger); | |
a0f65a26 | 905 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
6939c33a RW |
906 | nf_log_register(NFPROTO_IPV6, &ip6t_log_logger); |
907 | #endif | |
908 | return 0; | |
909 | } | |
910 | ||
911 | static void __exit log_tg_exit(void) | |
912 | { | |
913 | nf_log_unregister(&ipt_log_logger); | |
a0f65a26 | 914 | #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) |
6939c33a RW |
915 | nf_log_unregister(&ip6t_log_logger); |
916 | #endif | |
917 | xt_unregister_targets(log_tg_regs, ARRAY_SIZE(log_tg_regs)); | |
918 | } | |
919 | ||
920 | module_init(log_tg_init); | |
921 | module_exit(log_tg_exit); | |
922 | ||
923 | MODULE_LICENSE("GPL"); | |
924 | MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>"); | |
925 | MODULE_AUTHOR("Jan Rekorajski <baggins@pld.org.pl>"); | |
926 | MODULE_DESCRIPTION("Xtables: IPv4/IPv6 packet logging"); | |
927 | MODULE_ALIAS("ipt_LOG"); | |
928 | MODULE_ALIAS("ip6t_LOG"); |