1 /*-
2 * Copyright (c) 2002-2009 Luigi Rizzo, Universita` di Pisa
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23 * SUCH DAMAGE.
24 */
25
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
28
29 /*
30 * Logging support for ipfw
31 */
32
33 #include "opt_ipfw.h"
34 #include "opt_inet.h"
35 #ifndef INET
36 #error IPFIREWALL requires INET.
37 #endif /* INET */
38 #include "opt_inet6.h"
39
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/mbuf.h>
43 #include <sys/kernel.h>
44 #include <sys/socket.h>
45 #include <sys/sysctl.h>
46 #include <sys/syslog.h>
47 #include <sys/lock.h>
48 #include <sys/rwlock.h>
49 #include <net/ethernet.h> /* for ETHERTYPE_IP */
50 #include <net/if.h>
51 #include <net/if_var.h>
52 #include <net/if_clone.h>
53 #include <net/vnet.h>
54 #include <net/if_types.h> /* for IFT_PFLOG */
55 #include <net/bpf.h> /* for BPF */
56
57 #include <netinet/in.h>
58 #include <netinet/ip.h>
59 #include <netinet/ip_icmp.h>
60 #include <netinet/ip_var.h>
61 #include <netinet/ip_fw.h>
62 #include <netinet/tcp_var.h>
63 #include <netinet/udp.h>
64
65 #include <netinet/ip6.h>
66 #include <netinet/icmp6.h>
67 #ifdef INET6
68 #include <netinet6/in6_var.h> /* ip6_sprintf() */
69 #endif
70
71 #include <netpfil/ipfw/ip_fw_private.h>
72
73 #ifdef MAC
74 #include <security/mac/mac_framework.h>
75 #endif
76
77 /*
78 * L3HDR maps an ipv4 pointer into a layer3 header pointer of type T
79 * Other macros just cast void * into the appropriate type
80 */
81 #define L3HDR(T, ip) ((T *)((u_int32_t *)(ip) + (ip)->ip_hl))
82 #define TCP(p) ((struct tcphdr *)(p))
83 #define SCTP(p) ((struct sctphdr *)(p))
84 #define UDP(p) ((struct udphdr *)(p))
85 #define ICMP(p) ((struct icmphdr *)(p))
86 #define ICMP6(p) ((struct icmp6_hdr *)(p))
87
88 #ifdef __APPLE__
89 #undef snprintf
90 #define snprintf sprintf
91 #define SNPARGS(buf, len) buf + len
92 #define SNP(buf) buf
93 #else /* !__APPLE__ */
94 #define SNPARGS(buf, len) buf + len, sizeof(buf) > len ? sizeof(buf) - len : 0
95 #define SNP(buf) buf, sizeof(buf)
96 #endif /* !__APPLE__ */
97
98 #ifdef WITHOUT_BPF
99 void
ipfw_log_bpf(int onoff)100 ipfw_log_bpf(int onoff)
101 {
102 }
103 #else /* !WITHOUT_BPF */
104 static struct ifnet *log_if; /* hook to attach to bpf */
105 static struct rwlock log_if_lock;
106 #define LOGIF_LOCK_INIT(x) rw_init(&log_if_lock, "ipfw log_if lock")
107 #define LOGIF_LOCK_DESTROY(x) rw_destroy(&log_if_lock)
108 #define LOGIF_RLOCK(x) rw_rlock(&log_if_lock)
109 #define LOGIF_RUNLOCK(x) rw_runlock(&log_if_lock)
110 #define LOGIF_WLOCK(x) rw_wlock(&log_if_lock)
111 #define LOGIF_WUNLOCK(x) rw_wunlock(&log_if_lock)
112
113 static const char ipfwname[] = "ipfw";
114
115 /* we use this dummy function for all ifnet callbacks */
116 static int
log_dummy(struct ifnet * ifp,u_long cmd,caddr_t addr)117 log_dummy(struct ifnet *ifp, u_long cmd, caddr_t addr)
118 {
119 return EINVAL;
120 }
121
122 static int
ipfw_log_output(struct ifnet * ifp,struct mbuf * m,const struct sockaddr * dst,struct route * ro)123 ipfw_log_output(struct ifnet *ifp, struct mbuf *m,
124 const struct sockaddr *dst, struct route *ro)
125 {
126 if (m != NULL)
127 FREE_PKT(m);
128 return EINVAL;
129 }
130
131 static void
ipfw_log_start(struct ifnet * ifp)132 ipfw_log_start(struct ifnet* ifp)
133 {
134 panic("ipfw_log_start() must not be called");
135 }
136
137 static const u_char ipfwbroadcastaddr[6] =
138 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
139
140 static int
ipfw_log_clone_match(struct if_clone * ifc,const char * name)141 ipfw_log_clone_match(struct if_clone *ifc, const char *name)
142 {
143
144 return (strncmp(name, ipfwname, sizeof(ipfwname) - 1) == 0);
145 }
146
147 static int
ipfw_log_clone_create(struct if_clone * ifc,char * name,size_t len,caddr_t params)148 ipfw_log_clone_create(struct if_clone *ifc, char *name, size_t len,
149 caddr_t params)
150 {
151 int error;
152 int unit;
153 struct ifnet *ifp;
154
155 error = ifc_name2unit(name, &unit);
156 if (error)
157 return (error);
158
159 error = ifc_alloc_unit(ifc, &unit);
160 if (error)
161 return (error);
162
163 ifp = if_alloc(IFT_PFLOG);
164 if (ifp == NULL) {
165 ifc_free_unit(ifc, unit);
166 return (ENOSPC);
167 }
168 ifp->if_dname = ipfwname;
169 ifp->if_dunit = unit;
170 snprintf(ifp->if_xname, IFNAMSIZ, "%s%d", ipfwname, unit);
171 strlcpy(name, ifp->if_xname, len);
172 ifp->if_mtu = 65536;
173 ifp->if_flags = IFF_UP | IFF_SIMPLEX | IFF_MULTICAST;
174 ifp->if_init = (void *)log_dummy;
175 ifp->if_ioctl = log_dummy;
176 ifp->if_start = ipfw_log_start;
177 ifp->if_output = ipfw_log_output;
178 ifp->if_addrlen = 6;
179 ifp->if_hdrlen = 14;
180 ifp->if_broadcastaddr = ipfwbroadcastaddr;
181 ifp->if_baudrate = IF_Mbps(10);
182
183 LOGIF_WLOCK();
184 if (log_if == NULL)
185 log_if = ifp;
186 else {
187 LOGIF_WUNLOCK();
188 if_free(ifp);
189 ifc_free_unit(ifc, unit);
190 return (EEXIST);
191 }
192 LOGIF_WUNLOCK();
193 if_attach(ifp);
194 bpfattach(ifp, DLT_EN10MB, 14);
195
196 return (0);
197 }
198
199 static int
ipfw_log_clone_destroy(struct if_clone * ifc,struct ifnet * ifp)200 ipfw_log_clone_destroy(struct if_clone *ifc, struct ifnet *ifp)
201 {
202 int unit;
203
204 if (ifp == NULL)
205 return (0);
206
207 LOGIF_WLOCK();
208 if (log_if != NULL && ifp == log_if)
209 log_if = NULL;
210 else {
211 LOGIF_WUNLOCK();
212 return (EINVAL);
213 }
214 LOGIF_WUNLOCK();
215
216 unit = ifp->if_dunit;
217 bpfdetach(ifp);
218 if_detach(ifp);
219 if_free(ifp);
220 ifc_free_unit(ifc, unit);
221
222 return (0);
223 }
224
225 static struct if_clone *ipfw_log_cloner;
226
227 void
ipfw_log_bpf(int onoff)228 ipfw_log_bpf(int onoff)
229 {
230
231 if (onoff) {
232 LOGIF_LOCK_INIT();
233 ipfw_log_cloner = if_clone_advanced(ipfwname, 0,
234 ipfw_log_clone_match, ipfw_log_clone_create,
235 ipfw_log_clone_destroy);
236 } else {
237 if_clone_detach(ipfw_log_cloner);
238 LOGIF_LOCK_DESTROY();
239 }
240 }
241 #endif /* !WITHOUT_BPF */
242
243 #define TARG(k, f) IP_FW_ARG_TABLEARG(chain, k, f)
244 /*
245 * We enter here when we have a rule with O_LOG.
246 * XXX this function alone takes about 2Kbytes of code!
247 */
248 void
ipfw_log(struct ip_fw_chain * chain,struct ip_fw * f,u_int hlen,struct ip_fw_args * args,struct mbuf * m,struct ifnet * oif,u_short offset,uint32_t tablearg,struct ip * ip)249 ipfw_log(struct ip_fw_chain *chain, struct ip_fw *f, u_int hlen,
250 struct ip_fw_args *args, struct mbuf *m, struct ifnet *oif,
251 u_short offset, uint32_t tablearg, struct ip *ip)
252 {
253 char *action;
254 int limit_reached = 0;
255 char action2[92], proto[128], fragment[32];
256
257 if (V_fw_verbose == 0) {
258 #ifndef WITHOUT_BPF
259 LOGIF_RLOCK();
260 if (log_if == NULL || log_if->if_bpf == NULL) {
261 LOGIF_RUNLOCK();
262 return;
263 }
264
265 if (args->eh) /* layer2, use orig hdr */
266 BPF_MTAP2(log_if, args->eh, ETHER_HDR_LEN, m);
267 else {
268 /* Add fake header. Later we will store
269 * more info in the header.
270 */
271 if (ip->ip_v == 4)
272 BPF_MTAP2(log_if, "DDDDDDSSSSSS\x08\x00", ETHER_HDR_LEN, m);
273 else if (ip->ip_v == 6)
274 BPF_MTAP2(log_if, "DDDDDDSSSSSS\x86\xdd", ETHER_HDR_LEN, m);
275 else
276 /* Obviously bogus EtherType. */
277 BPF_MTAP2(log_if, "DDDDDDSSSSSS\xff\xff", ETHER_HDR_LEN, m);
278 }
279 LOGIF_RUNLOCK();
280 #endif /* !WITHOUT_BPF */
281 return;
282 }
283 /* the old 'log' function */
284 fragment[0] = '\0';
285 proto[0] = '\0';
286
287 if (f == NULL) { /* bogus pkt */
288 if (V_verbose_limit != 0 && V_norule_counter >= V_verbose_limit)
289 return;
290 V_norule_counter++;
291 if (V_norule_counter == V_verbose_limit)
292 limit_reached = V_verbose_limit;
293 action = "Refuse";
294 } else { /* O_LOG is the first action, find the real one */
295 ipfw_insn *cmd = ACTION_PTR(f);
296 ipfw_insn_log *l = (ipfw_insn_log *)cmd;
297
298 if (l->max_log != 0 && l->log_left == 0)
299 return;
300 l->log_left--;
301 if (l->log_left == 0)
302 limit_reached = l->max_log;
303 cmd += F_LEN(cmd); /* point to first action */
304 if (cmd->opcode == O_ALTQ) {
305 ipfw_insn_altq *altq = (ipfw_insn_altq *)cmd;
306
307 snprintf(SNPARGS(action2, 0), "Altq %d",
308 altq->qid);
309 cmd += F_LEN(cmd);
310 }
311 if (cmd->opcode == O_PROB || cmd->opcode == O_TAG ||
312 cmd->opcode == O_SETDSCP)
313 cmd += F_LEN(cmd);
314
315 action = action2;
316 switch (cmd->opcode) {
317 case O_DENY:
318 action = "Deny";
319 break;
320
321 case O_REJECT:
322 if (cmd->arg1==ICMP_REJECT_RST)
323 action = "Reset";
324 else if (cmd->arg1==ICMP_UNREACH_HOST)
325 action = "Reject";
326 else
327 snprintf(SNPARGS(action2, 0), "Unreach %d",
328 cmd->arg1);
329 break;
330
331 case O_UNREACH6:
332 if (cmd->arg1==ICMP6_UNREACH_RST)
333 action = "Reset";
334 else
335 snprintf(SNPARGS(action2, 0), "Unreach %d",
336 cmd->arg1);
337 break;
338
339 case O_ACCEPT:
340 action = "Accept";
341 break;
342 case O_COUNT:
343 action = "Count";
344 break;
345 case O_DIVERT:
346 snprintf(SNPARGS(action2, 0), "Divert %d",
347 TARG(cmd->arg1, divert));
348 break;
349 case O_TEE:
350 snprintf(SNPARGS(action2, 0), "Tee %d",
351 TARG(cmd->arg1, divert));
352 break;
353 case O_SETFIB:
354 snprintf(SNPARGS(action2, 0), "SetFib %d",
355 TARG(cmd->arg1, fib) & 0x7FFF);
356 break;
357 case O_SKIPTO:
358 snprintf(SNPARGS(action2, 0), "SkipTo %d",
359 TARG(cmd->arg1, skipto));
360 break;
361 case O_PIPE:
362 snprintf(SNPARGS(action2, 0), "Pipe %d",
363 TARG(cmd->arg1, pipe));
364 break;
365 case O_QUEUE:
366 snprintf(SNPARGS(action2, 0), "Queue %d",
367 TARG(cmd->arg1, pipe));
368 break;
369 case O_FORWARD_IP: {
370 ipfw_insn_sa *sa = (ipfw_insn_sa *)cmd;
371 int len;
372 struct in_addr dummyaddr;
373 if (sa->sa.sin_addr.s_addr == INADDR_ANY)
374 dummyaddr.s_addr = htonl(tablearg);
375 else
376 dummyaddr.s_addr = sa->sa.sin_addr.s_addr;
377
378 len = snprintf(SNPARGS(action2, 0), "Forward to %s",
379 inet_ntoa(dummyaddr));
380
381 if (sa->sa.sin_port)
382 snprintf(SNPARGS(action2, len), ":%d",
383 sa->sa.sin_port);
384 }
385 break;
386 #ifdef INET6
387 case O_FORWARD_IP6: {
388 char buf[INET6_ADDRSTRLEN];
389 ipfw_insn_sa6 *sa = (ipfw_insn_sa6 *)cmd;
390 int len;
391
392 len = snprintf(SNPARGS(action2, 0), "Forward to [%s]",
393 ip6_sprintf(buf, &sa->sa.sin6_addr));
394
395 if (sa->sa.sin6_port)
396 snprintf(SNPARGS(action2, len), ":%u",
397 sa->sa.sin6_port);
398 }
399 break;
400 #endif
401 case O_NETGRAPH:
402 snprintf(SNPARGS(action2, 0), "Netgraph %d",
403 cmd->arg1);
404 break;
405 case O_NGTEE:
406 snprintf(SNPARGS(action2, 0), "Ngtee %d",
407 cmd->arg1);
408 break;
409 case O_NAT:
410 action = "Nat";
411 break;
412 case O_REASS:
413 action = "Reass";
414 break;
415 case O_CALLRETURN:
416 if (cmd->len & F_NOT)
417 action = "Return";
418 else
419 snprintf(SNPARGS(action2, 0), "Call %d",
420 cmd->arg1);
421 break;
422 default:
423 action = "UNKNOWN";
424 break;
425 }
426 }
427
428 if (hlen == 0) { /* non-ip */
429 snprintf(SNPARGS(proto, 0), "MAC");
430
431 } else {
432 int len;
433 #ifdef INET6
434 char src[INET6_ADDRSTRLEN + 2], dst[INET6_ADDRSTRLEN + 2];
435 #else
436 char src[INET_ADDRSTRLEN], dst[INET_ADDRSTRLEN];
437 #endif
438 struct icmphdr *icmp;
439 struct tcphdr *tcp;
440 struct udphdr *udp;
441 #ifdef INET6
442 struct ip6_hdr *ip6 = NULL;
443 struct icmp6_hdr *icmp6;
444 u_short ip6f_mf;
445 #endif
446 src[0] = '\0';
447 dst[0] = '\0';
448 #ifdef INET6
449 ip6f_mf = offset & IP6F_MORE_FRAG;
450 offset &= IP6F_OFF_MASK;
451
452 if (IS_IP6_FLOW_ID(&(args->f_id))) {
453 char ip6buf[INET6_ADDRSTRLEN];
454 snprintf(src, sizeof(src), "[%s]",
455 ip6_sprintf(ip6buf, &args->f_id.src_ip6));
456 snprintf(dst, sizeof(dst), "[%s]",
457 ip6_sprintf(ip6buf, &args->f_id.dst_ip6));
458
459 ip6 = (struct ip6_hdr *)ip;
460 tcp = (struct tcphdr *)(((char *)ip) + hlen);
461 udp = (struct udphdr *)(((char *)ip) + hlen);
462 } else
463 #endif
464 {
465 tcp = L3HDR(struct tcphdr, ip);
466 udp = L3HDR(struct udphdr, ip);
467
468 inet_ntop(AF_INET, &ip->ip_src, src, sizeof(src));
469 inet_ntop(AF_INET, &ip->ip_dst, dst, sizeof(dst));
470 }
471
472 switch (args->f_id.proto) {
473 case IPPROTO_TCP:
474 len = snprintf(SNPARGS(proto, 0), "TCP %s", src);
475 if (offset == 0)
476 snprintf(SNPARGS(proto, len), ":%d %s:%d",
477 ntohs(tcp->th_sport),
478 dst,
479 ntohs(tcp->th_dport));
480 else
481 snprintf(SNPARGS(proto, len), " %s", dst);
482 break;
483
484 case IPPROTO_UDP:
485 len = snprintf(SNPARGS(proto, 0), "UDP %s", src);
486 if (offset == 0)
487 snprintf(SNPARGS(proto, len), ":%d %s:%d",
488 ntohs(udp->uh_sport),
489 dst,
490 ntohs(udp->uh_dport));
491 else
492 snprintf(SNPARGS(proto, len), " %s", dst);
493 break;
494
495 case IPPROTO_ICMP:
496 icmp = L3HDR(struct icmphdr, ip);
497 if (offset == 0)
498 len = snprintf(SNPARGS(proto, 0),
499 "ICMP:%u.%u ",
500 icmp->icmp_type, icmp->icmp_code);
501 else
502 len = snprintf(SNPARGS(proto, 0), "ICMP ");
503 len += snprintf(SNPARGS(proto, len), "%s", src);
504 snprintf(SNPARGS(proto, len), " %s", dst);
505 break;
506 #ifdef INET6
507 case IPPROTO_ICMPV6:
508 icmp6 = (struct icmp6_hdr *)(((char *)ip) + hlen);
509 if (offset == 0)
510 len = snprintf(SNPARGS(proto, 0),
511 "ICMPv6:%u.%u ",
512 icmp6->icmp6_type, icmp6->icmp6_code);
513 else
514 len = snprintf(SNPARGS(proto, 0), "ICMPv6 ");
515 len += snprintf(SNPARGS(proto, len), "%s", src);
516 snprintf(SNPARGS(proto, len), " %s", dst);
517 break;
518 #endif
519 default:
520 len = snprintf(SNPARGS(proto, 0), "P:%d %s",
521 args->f_id.proto, src);
522 snprintf(SNPARGS(proto, len), " %s", dst);
523 break;
524 }
525
526 #ifdef INET6
527 if (IS_IP6_FLOW_ID(&(args->f_id))) {
528 if (offset || ip6f_mf)
529 snprintf(SNPARGS(fragment, 0),
530 " (frag %08x:%d@%d%s)",
531 args->f_id.extra,
532 ntohs(ip6->ip6_plen) - hlen,
533 ntohs(offset) << 3, ip6f_mf ? "+" : "");
534 } else
535 #endif
536 {
537 int ipoff, iplen;
538 ipoff = ntohs(ip->ip_off);
539 iplen = ntohs(ip->ip_len);
540 if (ipoff & (IP_MF | IP_OFFMASK))
541 snprintf(SNPARGS(fragment, 0),
542 " (frag %d:%d@%d%s)",
543 ntohs(ip->ip_id), iplen - (ip->ip_hl << 2),
544 offset << 3,
545 (ipoff & IP_MF) ? "+" : "");
546 }
547 }
548 #ifdef __FreeBSD__
549 if (oif || m->m_pkthdr.rcvif)
550 log(LOG_SECURITY | LOG_INFO,
551 "ipfw: %d %s %s %s via %s%s\n",
552 f ? f->rulenum : -1,
553 action, proto, oif ? "out" : "in",
554 oif ? oif->if_xname : m->m_pkthdr.rcvif->if_xname,
555 fragment);
556 else
557 #endif
558 log(LOG_SECURITY | LOG_INFO,
559 "ipfw: %d %s %s [no if info]%s\n",
560 f ? f->rulenum : -1,
561 action, proto, fragment);
562 if (limit_reached)
563 log(LOG_SECURITY | LOG_NOTICE,
564 "ipfw: limit %d reached on entry %d\n",
565 limit_reached, f ? f->rulenum : -1);
566 }
567 /* end of file */
568