ip_fw_log.c revision 201527 
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 201527 2010-01-04 19:01:22Z luigi $");
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_fw.h>
62#include <netinet/ipfw/ip_fw_private.h>
63#include <netinet/tcp_var.h>
64#include <netinet/udp.h>
65
66#include <netinet/ip6.h>
67#include <netinet/icmp6.h>
68#ifdef INET6
69#include <netinet6/in6_var.h>	/* ip6_sprintf() */
70#endif
71
72#ifdef MAC
73#include <security/mac/mac_framework.h>
74#endif
75
76/*
77 * L3HDR maps an ipv4 pointer into a layer3 header pointer of type T
78 * Other macros just cast void * into the appropriate type
79 */
80#define	L3HDR(T, ip)	((T *)((u_int32_t *)(ip) + (ip)->ip_hl))
81#define	TCP(p)		((struct tcphdr *)(p))
82#define	SCTP(p)		((struct sctphdr *)(p))
83#define	UDP(p)		((struct udphdr *)(p))
84#define	ICMP(p)		((struct icmphdr *)(p))
85#define	ICMP6(p)	((struct icmp6_hdr *)(p))
86
87#define SNPARGS(buf, len) buf + len, sizeof(buf) > len ? sizeof(buf) - len : 0
88#define SNP(buf) buf, sizeof(buf)
89
90#ifdef WITHOUT_BPF
91void
92ipfw_log_bpf(int onoff)
93{
94}
95#else /* !WITHOUT_BPF */
96static struct ifnet *log_if;	/* hook to attach to bpf */
97
98/* we use this dummy function for all ifnet callbacks */
99static int
100log_dummy(struct ifnet *ifp, u_long cmd, caddr_t addr)
101{
102	return EINVAL;
103}
104
105void
106ipfw_log_bpf(int onoff)
107{
108	struct ifnet *ifp;
109
110	if (onoff) {
111		if (log_if)
112			return;
113		ifp = if_alloc(IFT_ETHER);
114		if (ifp == NULL)
115			return;
116		if_initname(ifp, "ipfw", 0);
117		ifp->if_mtu = 65536;
118		ifp->if_flags = IFF_UP | IFF_SIMPLEX | IFF_MULTICAST;
119		ifp->if_init = (void *)log_dummy;
120		ifp->if_ioctl = log_dummy;
121		ifp->if_start = (void *)log_dummy;
122		ifp->if_output = (void *)log_dummy;
123		ifp->if_addrlen = 6;
124		ifp->if_hdrlen = 14;
125		if_attach(ifp);
126		ifp->if_baudrate = IF_Mbps(10);
127		bpfattach(ifp, DLT_EN10MB, 14);
128		log_if = ifp;
129	} else {
130		if (log_if) {
131			ether_ifdetach(log_if);
132			if_free(log_if);
133		}
134		log_if = NULL;
135	}
136}
137#endif /* !WITHOUT_BPF */
138
139/*
140 * We enter here when we have a rule with O_LOG.
141 * XXX this function alone takes about 2Kbytes of code!
142 */
143void
144ipfw_log(struct ip_fw *f, u_int hlen, struct ip_fw_args *args,
145    struct mbuf *m, struct ifnet *oif, u_short offset, uint32_t tablearg,
146    struct ip *ip)
147{
148	char *action;
149	int limit_reached = 0;
150	char action2[40], proto[128], fragment[32];
151
152	if (V_fw_verbose == 0) {
153#ifndef WITHOUT_BPF
154		struct m_hdr mh;
155
156		if (log_if == NULL || log_if->if_bpf == NULL)
157			return;
158		/* BPF treats the "mbuf" as read-only */
159		mh.mh_next = m;
160		mh.mh_len = ETHER_HDR_LEN;
161		if (args->eh) { /* layer2, use orig hdr */
162			mh.mh_data = (char *)args->eh;
163		} else {
164			/* add fake header. Later we will store
165			 * more info in the header
166			 */
167			mh.mh_data = "DDDDDDSSSSSS\x08\x00";
168		}
169		BPF_MTAP(log_if, (struct mbuf *)&mh);
170#endif /* !WITHOUT_BPF */
171		return;
172	}
173	/* the old 'log' function */
174	fragment[0] = '\0';
175	proto[0] = '\0';
176
177	if (f == NULL) {	/* bogus pkt */
178		if (V_verbose_limit != 0 && V_norule_counter >= V_verbose_limit)
179			return;
180		V_norule_counter++;
181		if (V_norule_counter == V_verbose_limit)
182			limit_reached = V_verbose_limit;
183		action = "Refuse";
184	} else {	/* O_LOG is the first action, find the real one */
185		ipfw_insn *cmd = ACTION_PTR(f);
186		ipfw_insn_log *l = (ipfw_insn_log *)cmd;
187
188		if (l->max_log != 0 && l->log_left == 0)
189			return;
190		l->log_left--;
191		if (l->log_left == 0)
192			limit_reached = l->max_log;
193		cmd += F_LEN(cmd);	/* point to first action */
194		if (cmd->opcode == O_ALTQ) {
195			ipfw_insn_altq *altq = (ipfw_insn_altq *)cmd;
196
197			snprintf(SNPARGS(action2, 0), "Altq %d",
198				altq->qid);
199			cmd += F_LEN(cmd);
200		}
201		if (cmd->opcode == O_PROB)
202			cmd += F_LEN(cmd);
203
204		if (cmd->opcode == O_TAG)
205			cmd += F_LEN(cmd);
206
207		action = action2;
208		switch (cmd->opcode) {
209		case O_DENY:
210			action = "Deny";
211			break;
212
213		case O_REJECT:
214			if (cmd->arg1==ICMP_REJECT_RST)
215				action = "Reset";
216			else if (cmd->arg1==ICMP_UNREACH_HOST)
217				action = "Reject";
218			else
219				snprintf(SNPARGS(action2, 0), "Unreach %d",
220					cmd->arg1);
221			break;
222
223		case O_UNREACH6:
224			if (cmd->arg1==ICMP6_UNREACH_RST)
225				action = "Reset";
226			else
227				snprintf(SNPARGS(action2, 0), "Unreach %d",
228					cmd->arg1);
229			break;
230
231		case O_ACCEPT:
232			action = "Accept";
233			break;
234		case O_COUNT:
235			action = "Count";
236			break;
237		case O_DIVERT:
238			snprintf(SNPARGS(action2, 0), "Divert %d",
239				cmd->arg1);
240			break;
241		case O_TEE:
242			snprintf(SNPARGS(action2, 0), "Tee %d",
243				cmd->arg1);
244			break;
245		case O_SETFIB:
246			snprintf(SNPARGS(action2, 0), "SetFib %d",
247				cmd->arg1);
248			break;
249		case O_SKIPTO:
250			snprintf(SNPARGS(action2, 0), "SkipTo %d",
251				cmd->arg1);
252			break;
253		case O_PIPE:
254			snprintf(SNPARGS(action2, 0), "Pipe %d",
255				cmd->arg1);
256			break;
257		case O_QUEUE:
258			snprintf(SNPARGS(action2, 0), "Queue %d",
259				cmd->arg1);
260			break;
261		case O_FORWARD_IP: {
262			ipfw_insn_sa *sa = (ipfw_insn_sa *)cmd;
263			int len;
264			struct in_addr dummyaddr;
265			if (sa->sa.sin_addr.s_addr == INADDR_ANY)
266				dummyaddr.s_addr = htonl(tablearg);
267			else
268				dummyaddr.s_addr = sa->sa.sin_addr.s_addr;
269
270			len = snprintf(SNPARGS(action2, 0), "Forward to %s",
271				inet_ntoa(dummyaddr));
272
273			if (sa->sa.sin_port)
274				snprintf(SNPARGS(action2, len), ":%d",
275				    sa->sa.sin_port);
276			}
277			break;
278		case O_NETGRAPH:
279			snprintf(SNPARGS(action2, 0), "Netgraph %d",
280				cmd->arg1);
281			break;
282		case O_NGTEE:
283			snprintf(SNPARGS(action2, 0), "Ngtee %d",
284				cmd->arg1);
285			break;
286		case O_NAT:
287			action = "Nat";
288 			break;
289		case O_REASS:
290			action = "Reass";
291			break;
292		default:
293			action = "UNKNOWN";
294			break;
295		}
296	}
297
298	if (hlen == 0) {	/* non-ip */
299		snprintf(SNPARGS(proto, 0), "MAC");
300
301	} else {
302		int len;
303#ifdef INET6
304		char src[INET6_ADDRSTRLEN + 2], dst[INET6_ADDRSTRLEN + 2];
305#else
306		char src[INET_ADDRSTRLEN], dst[INET_ADDRSTRLEN];
307#endif
308		struct icmphdr *icmp;
309		struct tcphdr *tcp;
310		struct udphdr *udp;
311#ifdef INET6
312		struct ip6_hdr *ip6 = NULL;
313		struct icmp6_hdr *icmp6;
314#endif
315		src[0] = '\0';
316		dst[0] = '\0';
317#ifdef INET6
318		if (IS_IP6_FLOW_ID(&(args->f_id))) {
319			char ip6buf[INET6_ADDRSTRLEN];
320			snprintf(src, sizeof(src), "[%s]",
321			    ip6_sprintf(ip6buf, &args->f_id.src_ip6));
322			snprintf(dst, sizeof(dst), "[%s]",
323			    ip6_sprintf(ip6buf, &args->f_id.dst_ip6));
324
325			ip6 = (struct ip6_hdr *)ip;
326			tcp = (struct tcphdr *)(((char *)ip) + hlen);
327			udp = (struct udphdr *)(((char *)ip) + hlen);
328		} else
329#endif
330		{
331			tcp = L3HDR(struct tcphdr, ip);
332			udp = L3HDR(struct udphdr, ip);
333
334			inet_ntoa_r(ip->ip_src, src);
335			inet_ntoa_r(ip->ip_dst, dst);
336		}
337
338		switch (args->f_id.proto) {
339		case IPPROTO_TCP:
340			len = snprintf(SNPARGS(proto, 0), "TCP %s", src);
341			if (offset == 0)
342				snprintf(SNPARGS(proto, len), ":%d %s:%d",
343				    ntohs(tcp->th_sport),
344				    dst,
345				    ntohs(tcp->th_dport));
346			else
347				snprintf(SNPARGS(proto, len), " %s", dst);
348			break;
349
350		case IPPROTO_UDP:
351			len = snprintf(SNPARGS(proto, 0), "UDP %s", src);
352			if (offset == 0)
353				snprintf(SNPARGS(proto, len), ":%d %s:%d",
354				    ntohs(udp->uh_sport),
355				    dst,
356				    ntohs(udp->uh_dport));
357			else
358				snprintf(SNPARGS(proto, len), " %s", dst);
359			break;
360
361		case IPPROTO_ICMP:
362			icmp = L3HDR(struct icmphdr, ip);
363			if (offset == 0)
364				len = snprintf(SNPARGS(proto, 0),
365				    "ICMP:%u.%u ",
366				    icmp->icmp_type, icmp->icmp_code);
367			else
368				len = snprintf(SNPARGS(proto, 0), "ICMP ");
369			len += snprintf(SNPARGS(proto, len), "%s", src);
370			snprintf(SNPARGS(proto, len), " %s", dst);
371			break;
372#ifdef INET6
373		case IPPROTO_ICMPV6:
374			icmp6 = (struct icmp6_hdr *)(((char *)ip) + hlen);
375			if (offset == 0)
376				len = snprintf(SNPARGS(proto, 0),
377				    "ICMPv6:%u.%u ",
378				    icmp6->icmp6_type, icmp6->icmp6_code);
379			else
380				len = snprintf(SNPARGS(proto, 0), "ICMPv6 ");
381			len += snprintf(SNPARGS(proto, len), "%s", src);
382			snprintf(SNPARGS(proto, len), " %s", dst);
383			break;
384#endif
385		default:
386			len = snprintf(SNPARGS(proto, 0), "P:%d %s",
387			    args->f_id.proto, src);
388			snprintf(SNPARGS(proto, len), " %s", dst);
389			break;
390		}
391
392#ifdef INET6
393		if (IS_IP6_FLOW_ID(&(args->f_id))) {
394			if (offset & (IP6F_OFF_MASK | IP6F_MORE_FRAG))
395				snprintf(SNPARGS(fragment, 0),
396				    " (frag %08x:%d@%d%s)",
397				    args->f_id.frag_id6,
398				    ntohs(ip6->ip6_plen) - hlen,
399				    ntohs(offset & IP6F_OFF_MASK) << 3,
400				    (offset & IP6F_MORE_FRAG) ? "+" : "");
401		} else
402#endif
403		{
404			int ipoff, iplen;
405			ipoff = ntohs(ip->ip_off);
406			iplen = ntohs(ip->ip_len);
407			if (ipoff & (IP_MF | IP_OFFMASK))
408				snprintf(SNPARGS(fragment, 0),
409				    " (frag %d:%d@%d%s)",
410				    ntohs(ip->ip_id), iplen - (ip->ip_hl << 2),
411				    offset << 3,
412				    (ipoff & IP_MF) ? "+" : "");
413		}
414	}
415	if (oif || m->m_pkthdr.rcvif)
416		log(LOG_SECURITY | LOG_INFO,
417		    "ipfw: %d %s %s %s via %s%s\n",
418		    f ? f->rulenum : -1,
419		    action, proto, oif ? "out" : "in",
420		    oif ? oif->if_xname : m->m_pkthdr.rcvif->if_xname,
421		    fragment);
422	else
423		log(LOG_SECURITY | LOG_INFO,
424		    "ipfw: %d %s %s [no if info]%s\n",
425		    f ? f->rulenum : -1,
426		    action, proto, fragment);
427	if (limit_reached)
428		log(LOG_SECURITY | LOG_NOTICE,
429		    "ipfw: limit %d reached on entry %d\n",
430		    limit_reached, f ? f->rulenum : -1);
431}
432/* end of file */
433