ip_fw_log.c revision 225044 
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: head/sys/netinet/ipfw/ip_fw_log.c 225044 2011-08-20 17:05:11Z bz $");
28
29/*
30 * Logging support for ipfw
31 */
32
33#if !defined(KLD_MODULE)
34#include "opt_ipfw.h"
35#include "opt_ipdivert.h"
36#include "opt_ipdn.h"
37#include "opt_inet.h"
38#ifndef INET
39#error IPFIREWALL requires INET.
40#endif /* INET */
41#endif
42#include "opt_inet6.h"
43#include "opt_ipsec.h"
44
45#include <sys/param.h>
46#include <sys/systm.h>
47#include <sys/mbuf.h>
48#include <sys/kernel.h>
49#include <sys/socket.h>
50#include <sys/sysctl.h>
51#include <sys/syslog.h>
52#include <net/ethernet.h> /* for ETHERTYPE_IP */
53#include <net/if.h>
54#include <net/vnet.h>
55#include <net/if_types.h>	/* for IFT_ETHER */
56#include <net/bpf.h>		/* for BPF */
57
58#include <netinet/in.h>
59#include <netinet/ip.h>
60#include <netinet/ip_icmp.h>
61#include <netinet/ip_var.h>
62#include <netinet/ip_fw.h>
63#include <netinet/ipfw/ip_fw_private.h>
64#include <netinet/tcp_var.h>
65#include <netinet/udp.h>
66
67#include <netinet/ip6.h>
68#include <netinet/icmp6.h>
69#ifdef INET6
70#include <netinet6/in6_var.h>	/* ip6_sprintf() */
71#endif
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#define SNPARGS(buf, len) buf + len, sizeof(buf) > len ? sizeof(buf) - len : 0
89#define SNP(buf) buf, sizeof(buf)
90
91#ifdef WITHOUT_BPF
92void
93ipfw_log_bpf(int onoff)
94{
95}
96#else /* !WITHOUT_BPF */
97static struct ifnet *log_if;	/* hook to attach to bpf */
98
99/* we use this dummy function for all ifnet callbacks */
100static int
101log_dummy(struct ifnet *ifp, u_long cmd, caddr_t addr)
102{
103	return EINVAL;
104}
105
106static int
107ipfw_log_output(struct ifnet *ifp, struct mbuf *m,
108	struct sockaddr *dst, struct route *ro)
109{
110	if (m != NULL)
111		m_freem(m);
112	return EINVAL;
113}
114
115static void
116ipfw_log_start(struct ifnet* ifp)
117{
118	panic("ipfw_log_start() must not be called");
119}
120
121static const u_char ipfwbroadcastaddr[6] =
122	{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
123
124void
125ipfw_log_bpf(int onoff)
126{
127	struct ifnet *ifp;
128
129	if (onoff) {
130		if (log_if)
131			return;
132		ifp = if_alloc(IFT_ETHER);
133		if (ifp == NULL)
134			return;
135		if_initname(ifp, "ipfw", 0);
136		ifp->if_mtu = 65536;
137		ifp->if_flags = IFF_UP | IFF_SIMPLEX | IFF_MULTICAST;
138		ifp->if_init = (void *)log_dummy;
139		ifp->if_ioctl = log_dummy;
140		ifp->if_start = ipfw_log_start;
141		ifp->if_output = ipfw_log_output;
142		ifp->if_addrlen = 6;
143		ifp->if_hdrlen = 14;
144		if_attach(ifp);
145		ifp->if_broadcastaddr = ipfwbroadcastaddr;
146		ifp->if_baudrate = IF_Mbps(10);
147		bpfattach(ifp, DLT_EN10MB, 14);
148		log_if = ifp;
149	} else {
150		if (log_if) {
151			ether_ifdetach(log_if);
152			if_free(log_if);
153		}
154		log_if = NULL;
155	}
156}
157#endif /* !WITHOUT_BPF */
158
159/*
160 * We enter here when we have a rule with O_LOG.
161 * XXX this function alone takes about 2Kbytes of code!
162 */
163void
164ipfw_log(struct ip_fw *f, u_int hlen, struct ip_fw_args *args,
165    struct mbuf *m, struct ifnet *oif, u_short offset, uint32_t tablearg,
166    struct ip *ip)
167{
168	char *action;
169	int limit_reached = 0;
170	char action2[92], proto[128], fragment[32];
171
172	if (V_fw_verbose == 0) {
173#ifndef WITHOUT_BPF
174
175		if (log_if == NULL || log_if->if_bpf == NULL)
176			return;
177
178		if (args->eh) /* layer2, use orig hdr */
179			BPF_MTAP2(log_if, args->eh, ETHER_HDR_LEN, m);
180		else
181			/* Add fake header. Later we will store
182			 * more info in the header.
183			 */
184			BPF_MTAP2(log_if, "DDDDDDSSSSSS\x08\x00", ETHER_HDR_LEN, m);
185#endif /* !WITHOUT_BPF */
186		return;
187	}
188	/* the old 'log' function */
189	fragment[0] = '\0';
190	proto[0] = '\0';
191
192	if (f == NULL) {	/* bogus pkt */
193		if (V_verbose_limit != 0 && V_norule_counter >= V_verbose_limit)
194			return;
195		V_norule_counter++;
196		if (V_norule_counter == V_verbose_limit)
197			limit_reached = V_verbose_limit;
198		action = "Refuse";
199	} else {	/* O_LOG is the first action, find the real one */
200		ipfw_insn *cmd = ACTION_PTR(f);
201		ipfw_insn_log *l = (ipfw_insn_log *)cmd;
202
203		if (l->max_log != 0 && l->log_left == 0)
204			return;
205		l->log_left--;
206		if (l->log_left == 0)
207			limit_reached = l->max_log;
208		cmd += F_LEN(cmd);	/* point to first action */
209		if (cmd->opcode == O_ALTQ) {
210			ipfw_insn_altq *altq = (ipfw_insn_altq *)cmd;
211
212			snprintf(SNPARGS(action2, 0), "Altq %d",
213				altq->qid);
214			cmd += F_LEN(cmd);
215		}
216		if (cmd->opcode == O_PROB)
217			cmd += F_LEN(cmd);
218
219		if (cmd->opcode == O_TAG)
220			cmd += F_LEN(cmd);
221
222		action = action2;
223		switch (cmd->opcode) {
224		case O_DENY:
225			action = "Deny";
226			break;
227
228		case O_REJECT:
229			if (cmd->arg1==ICMP_REJECT_RST)
230				action = "Reset";
231			else if (cmd->arg1==ICMP_UNREACH_HOST)
232				action = "Reject";
233			else
234				snprintf(SNPARGS(action2, 0), "Unreach %d",
235					cmd->arg1);
236			break;
237
238		case O_UNREACH6:
239			if (cmd->arg1==ICMP6_UNREACH_RST)
240				action = "Reset";
241			else
242				snprintf(SNPARGS(action2, 0), "Unreach %d",
243					cmd->arg1);
244			break;
245
246		case O_ACCEPT:
247			action = "Accept";
248			break;
249		case O_COUNT:
250			action = "Count";
251			break;
252		case O_DIVERT:
253			snprintf(SNPARGS(action2, 0), "Divert %d",
254				cmd->arg1);
255			break;
256		case O_TEE:
257			snprintf(SNPARGS(action2, 0), "Tee %d",
258				cmd->arg1);
259			break;
260		case O_SETFIB:
261			snprintf(SNPARGS(action2, 0), "SetFib %d",
262				cmd->arg1);
263			break;
264		case O_SKIPTO:
265			snprintf(SNPARGS(action2, 0), "SkipTo %d",
266				cmd->arg1);
267			break;
268		case O_PIPE:
269			snprintf(SNPARGS(action2, 0), "Pipe %d",
270				cmd->arg1);
271			break;
272		case O_QUEUE:
273			snprintf(SNPARGS(action2, 0), "Queue %d",
274				cmd->arg1);
275			break;
276		case O_FORWARD_IP: {
277			ipfw_insn_sa *sa = (ipfw_insn_sa *)cmd;
278			int len;
279			struct in_addr dummyaddr;
280			if (sa->sa.sin_addr.s_addr == INADDR_ANY)
281				dummyaddr.s_addr = htonl(tablearg);
282			else
283				dummyaddr.s_addr = sa->sa.sin_addr.s_addr;
284
285			len = snprintf(SNPARGS(action2, 0), "Forward to %s",
286				inet_ntoa(dummyaddr));
287
288			if (sa->sa.sin_port)
289				snprintf(SNPARGS(action2, len), ":%d",
290				    sa->sa.sin_port);
291			}
292			break;
293#ifdef INET6
294		case O_FORWARD_IP6: {
295			char buf[INET6_ADDRSTRLEN];
296			ipfw_insn_sa6 *sa = (ipfw_insn_sa6 *)cmd;
297			int len;
298
299			len = snprintf(SNPARGS(action2, 0), "Forward to [%s]",
300			    ip6_sprintf(buf, &sa->sa.sin6_addr));
301
302			if (sa->sa.sin6_port)
303				snprintf(SNPARGS(action2, len), ":%u",
304				    sa->sa.sin6_port);
305			}
306			break;
307#endif
308		case O_NETGRAPH:
309			snprintf(SNPARGS(action2, 0), "Netgraph %d",
310				cmd->arg1);
311			break;
312		case O_NGTEE:
313			snprintf(SNPARGS(action2, 0), "Ngtee %d",
314				cmd->arg1);
315			break;
316		case O_NAT:
317			action = "Nat";
318 			break;
319		case O_REASS:
320			action = "Reass";
321			break;
322		case O_CALLRETURN:
323			if (cmd->len & F_NOT)
324				action = "Return";
325			else
326				snprintf(SNPARGS(action2, 0), "Call %d",
327				    cmd->arg1);
328			break;
329		default:
330			action = "UNKNOWN";
331			break;
332		}
333	}
334
335	if (hlen == 0) {	/* non-ip */
336		snprintf(SNPARGS(proto, 0), "MAC");
337
338	} else {
339		int len;
340#ifdef INET6
341		char src[INET6_ADDRSTRLEN + 2], dst[INET6_ADDRSTRLEN + 2];
342#else
343		char src[INET_ADDRSTRLEN], dst[INET_ADDRSTRLEN];
344#endif
345		struct icmphdr *icmp;
346		struct tcphdr *tcp;
347		struct udphdr *udp;
348#ifdef INET6
349		struct ip6_hdr *ip6 = NULL;
350		struct icmp6_hdr *icmp6;
351		u_short ip6f_mf;
352#endif
353		src[0] = '\0';
354		dst[0] = '\0';
355#ifdef INET6
356		ip6f_mf = offset & IP6F_MORE_FRAG;
357		offset &= IP6F_OFF_MASK;
358
359		if (IS_IP6_FLOW_ID(&(args->f_id))) {
360			char ip6buf[INET6_ADDRSTRLEN];
361			snprintf(src, sizeof(src), "[%s]",
362			    ip6_sprintf(ip6buf, &args->f_id.src_ip6));
363			snprintf(dst, sizeof(dst), "[%s]",
364			    ip6_sprintf(ip6buf, &args->f_id.dst_ip6));
365
366			ip6 = (struct ip6_hdr *)ip;
367			tcp = (struct tcphdr *)(((char *)ip) + hlen);
368			udp = (struct udphdr *)(((char *)ip) + hlen);
369		} else
370#endif
371		{
372			tcp = L3HDR(struct tcphdr, ip);
373			udp = L3HDR(struct udphdr, ip);
374
375			inet_ntoa_r(ip->ip_src, src);
376			inet_ntoa_r(ip->ip_dst, dst);
377		}
378
379		switch (args->f_id.proto) {
380		case IPPROTO_TCP:
381			len = snprintf(SNPARGS(proto, 0), "TCP %s", src);
382			if (offset == 0)
383				snprintf(SNPARGS(proto, len), ":%d %s:%d",
384				    ntohs(tcp->th_sport),
385				    dst,
386				    ntohs(tcp->th_dport));
387			else
388				snprintf(SNPARGS(proto, len), " %s", dst);
389			break;
390
391		case IPPROTO_UDP:
392			len = snprintf(SNPARGS(proto, 0), "UDP %s", src);
393			if (offset == 0)
394				snprintf(SNPARGS(proto, len), ":%d %s:%d",
395				    ntohs(udp->uh_sport),
396				    dst,
397				    ntohs(udp->uh_dport));
398			else
399				snprintf(SNPARGS(proto, len), " %s", dst);
400			break;
401
402		case IPPROTO_ICMP:
403			icmp = L3HDR(struct icmphdr, ip);
404			if (offset == 0)
405				len = snprintf(SNPARGS(proto, 0),
406				    "ICMP:%u.%u ",
407				    icmp->icmp_type, icmp->icmp_code);
408			else
409				len = snprintf(SNPARGS(proto, 0), "ICMP ");
410			len += snprintf(SNPARGS(proto, len), "%s", src);
411			snprintf(SNPARGS(proto, len), " %s", dst);
412			break;
413#ifdef INET6
414		case IPPROTO_ICMPV6:
415			icmp6 = (struct icmp6_hdr *)(((char *)ip) + hlen);
416			if (offset == 0)
417				len = snprintf(SNPARGS(proto, 0),
418				    "ICMPv6:%u.%u ",
419				    icmp6->icmp6_type, icmp6->icmp6_code);
420			else
421				len = snprintf(SNPARGS(proto, 0), "ICMPv6 ");
422			len += snprintf(SNPARGS(proto, len), "%s", src);
423			snprintf(SNPARGS(proto, len), " %s", dst);
424			break;
425#endif
426		default:
427			len = snprintf(SNPARGS(proto, 0), "P:%d %s",
428			    args->f_id.proto, src);
429			snprintf(SNPARGS(proto, len), " %s", dst);
430			break;
431		}
432
433#ifdef INET6
434		if (IS_IP6_FLOW_ID(&(args->f_id))) {
435			if (offset & (IP6F_OFF_MASK | IP6F_MORE_FRAG))
436				snprintf(SNPARGS(fragment, 0),
437				    " (frag %08x:%d@%d%s)",
438				    args->f_id.extra,
439				    ntohs(ip6->ip6_plen) - hlen,
440				    ntohs(offset) << 3, ip6f_mf ? "+" : "");
441		} else
442#endif
443		{
444			int ipoff, iplen;
445			ipoff = ntohs(ip->ip_off);
446			iplen = ntohs(ip->ip_len);
447			if (ipoff & (IP_MF | IP_OFFMASK))
448				snprintf(SNPARGS(fragment, 0),
449				    " (frag %d:%d@%d%s)",
450				    ntohs(ip->ip_id), iplen - (ip->ip_hl << 2),
451				    offset << 3,
452				    (ipoff & IP_MF) ? "+" : "");
453		}
454	}
455#ifdef __FreeBSD__
456	if (oif || m->m_pkthdr.rcvif)
457		log(LOG_SECURITY | LOG_INFO,
458		    "ipfw: %d %s %s %s via %s%s\n",
459		    f ? f->rulenum : -1,
460		    action, proto, oif ? "out" : "in",
461		    oif ? oif->if_xname : m->m_pkthdr.rcvif->if_xname,
462		    fragment);
463	else
464#endif
465		log(LOG_SECURITY | LOG_INFO,
466		    "ipfw: %d %s %s [no if info]%s\n",
467		    f ? f->rulenum : -1,
468		    action, proto, fragment);
469	if (limit_reached)
470		log(LOG_SECURITY | LOG_NOTICE,
471		    "ipfw: limit %d reached on entry %d\n",
472		    limit_reached, f ? f->rulenum : -1);
473}
474/* end of file */
475