1/*	$NetBSD: if_pflog.c,v 1.14 2008/12/19 18:49:38 cegger Exp $	*/
2/*	$OpenBSD: if_pflog.c,v 1.24 2007/05/26 17:13:30 jason Exp $	*/
3
4/*
5 * The authors of this code are John Ioannidis (ji@tla.org),
6 * Angelos D. Keromytis (kermit@csd.uch.gr) and
7 * Niels Provos (provos@physnet.uni-hamburg.de).
8 *
9 * This code was written by John Ioannidis for BSD/OS in Athens, Greece,
10 * in November 1995.
11 *
12 * Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
13 * by Angelos D. Keromytis.
14 *
15 * Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis
16 * and Niels Provos.
17 *
18 * Copyright (C) 1995, 1996, 1997, 1998 by John Ioannidis, Angelos D. Keromytis
19 * and Niels Provos.
20 * Copyright (c) 2001, Angelos D. Keromytis, Niels Provos.
21 *
22 * Permission to use, copy, and modify this software with or without fee
23 * is hereby granted, provided that this entire notice is included in
24 * all copies of any software which is or includes a copy or
25 * modification of this software.
26 * You may use this code under the GNU public license if you so wish. Please
27 * contribute changes back to the authors under this freer than GPL license
28 * so that we may further the use of strong encryption without limitations to
29 * all.
30 *
31 * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
32 * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
33 * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
34 * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
35 * PURPOSE.
36 */
37
38#include <sys/cdefs.h>
39__KERNEL_RCSID(0, "$NetBSD: if_pflog.c,v 1.17 2010/04/05 07:22:22 joerg Exp $");
40
41#ifdef _KERNEL_OPT
42#include "opt_inet.h"
43#endif
44
45#include "pflog.h"
46
47#include <sys/param.h>
48#include <sys/systm.h>
49#include <sys/mbuf.h>
50#include <sys/proc.h>
51#include <sys/socket.h>
52#include <sys/ioctl.h>
53
54#include <net/if.h>
55#include <net/if_types.h>
56#include <net/route.h>
57#include <net/bpf.h>
58
59#ifdef	INET
60#include <netinet/in.h>
61#include <netinet/in_var.h>
62#include <netinet/in_systm.h>
63#include <netinet/ip.h>
64#endif
65
66#ifdef INET6
67#ifndef INET
68#include <netinet/in.h>
69#endif
70#include <netinet6/nd6.h>
71#endif /* INET6 */
72
73#include <net/pfvar.h>
74#include <net/if_pflog.h>
75
76#define PFLOGMTU	(32768 + MHLEN + MLEN)
77
78#ifdef PFLOGDEBUG
79#define DPRINTF(x)    do { if (pflogdebug) printf x ; } while (0)
80#else
81#define DPRINTF(x)
82#endif
83
84void	pflogattach(int);
85#ifdef _MODULE
86void	pflogdetach(void);
87#endif /* _MODULE */
88int	pflogoutput(struct ifnet *, struct mbuf *, const struct sockaddr *,
89	    	       struct rtentry *);
90int	pflogioctl(struct ifnet *, u_long, void *);
91void	pflogstart(struct ifnet *);
92int	pflog_clone_create(struct if_clone *, int);
93int	pflog_clone_destroy(struct ifnet *);
94
95LIST_HEAD(, pflog_softc)	pflogif_list;
96struct if_clone	pflog_cloner =
97    IF_CLONE_INITIALIZER("pflog", pflog_clone_create, pflog_clone_destroy);
98
99struct ifnet	*pflogifs[PFLOGIFS_MAX];	/* for fast access */
100
101void
102pflogattach(int npflog)
103{
104	int i;
105
106	LIST_INIT(&pflogif_list);
107	for (i = 0; i < PFLOGIFS_MAX; i++)
108		pflogifs[i] = NULL;
109	if_clone_attach(&pflog_cloner);
110}
111
112#ifdef _MODULE
113void
114pflogdetach(void)
115{
116	int i;
117
118	for (i = 0; i < PFLOGIFS_MAX; i++) {
119		if (pflogifs[i] != NULL)
120			pflog_clone_destroy(pflogifs[i]);
121	}
122	if_clone_detach(&pflog_cloner);
123}
124#endif /* _MODULE */
125
126int
127pflog_clone_create(struct if_clone *ifc, int unit)
128{
129	struct ifnet *ifp;
130	struct pflog_softc *pflogif;
131	int s;
132
133	if (unit >= PFLOGIFS_MAX)
134		return (EINVAL);
135
136	if ((pflogif = malloc(sizeof(*pflogif), M_DEVBUF, M_NOWAIT|M_ZERO)) == NULL)
137		return (ENOMEM);
138
139	pflogif->sc_unit = unit;
140	ifp = &pflogif->sc_if;
141	snprintf(ifp->if_xname, sizeof ifp->if_xname, "pflog%d", unit);
142	ifp->if_softc = pflogif;
143	ifp->if_mtu = PFLOGMTU;
144	ifp->if_ioctl = pflogioctl;
145	ifp->if_output = pflogoutput;
146	ifp->if_start = pflogstart;
147	ifp->if_type = IFT_PFLOG;
148#ifndef __NetBSD__
149	ifp->if_snd.ifq_maxlen = ifqmaxlen;
150#endif /* !__NetBSD__ */
151	ifp->if_hdrlen = PFLOG_HDRLEN;
152	if_attach(ifp);
153	if_alloc_sadl(ifp);
154
155#ifdef __NetBSD__
156	bpf_attach(ifp, DLT_PFLOG, PFLOG_HDRLEN);
157#else
158	bpfattach(&pflogif->sc_if.if_bpf, ifp, DLT_PFLOG, PFLOG_HDRLEN);
159#endif /* !__NetBSD__ */
160
161	s = splnet();
162	LIST_INSERT_HEAD(&pflogif_list, pflogif, sc_list);
163	pflogifs[unit] = ifp;
164	splx(s);
165
166	return (0);
167}
168
169int
170pflog_clone_destroy(struct ifnet *ifp)
171{
172	struct pflog_softc	*pflogif = ifp->if_softc;
173	int			 s;
174
175	s = splnet();
176	pflogifs[pflogif->sc_unit] = NULL;
177	LIST_REMOVE(pflogif, sc_list);
178	splx(s);
179
180	bpf_detach(ifp);
181	if_detach(ifp);
182	free(pflogif, M_DEVBUF);
183	return (0);
184}
185
186/*
187 * Start output on the pflog interface.
188 */
189void
190pflogstart(struct ifnet *ifp)
191{
192	struct mbuf *m;
193	int s;
194
195	for (;;) {
196		s = splnet();
197		IF_DROP(&ifp->if_snd);
198		IF_DEQUEUE(&ifp->if_snd, m);
199		splx(s);
200
201		if (m == NULL)
202			return;
203		else
204			m_freem(m);
205	}
206}
207
208int
209pflogoutput(struct ifnet *ifp, struct mbuf *m,
210    const struct sockaddr *dst, struct rtentry *rt)
211{
212	m_freem(m);
213	return (0);
214}
215
216/* ARGSUSED */
217int
218pflogioctl(struct ifnet *ifp, u_long cmd, void *data)
219{
220	int error = 0;
221
222	switch (cmd) {
223	case SIOCSIFFLAGS:
224		if ((error = ifioctl_common(ifp, cmd, data)) != 0)
225			break;
226		/*FALLTHROUGH*/
227	case SIOCINITIFADDR:
228	case SIOCAIFADDR:
229	case SIOCSIFDSTADDR:
230		if (ifp->if_flags & IFF_UP)
231			ifp->if_flags |= IFF_RUNNING;
232		else
233			ifp->if_flags &= ~IFF_RUNNING;
234		break;
235	default:
236		error = ifioctl_common(ifp, cmd, data);
237	}
238
239	return error;
240}
241
242int
243pflog_packet(struct pfi_kif *kif, struct mbuf *m, sa_family_t af, u_int8_t dir,
244    u_int8_t reason, struct pf_rule *rm, struct pf_rule *am,
245    struct pf_ruleset *ruleset, struct pf_pdesc *pd)
246{
247	struct ifnet *ifn;
248	struct pfloghdr hdr;
249
250	if (kif == NULL || m == NULL || rm == NULL || pd == NULL)
251		return (-1);
252
253	if ((ifn = pflogifs[rm->logif]) == NULL || !ifn->if_bpf)
254		return (0);
255
256	bzero(&hdr, sizeof(hdr));
257	hdr.length = PFLOG_REAL_HDRLEN;
258	hdr.af = af;
259	hdr.action = rm->action;
260	hdr.reason = reason;
261	memcpy(hdr.ifname, kif->pfik_name, sizeof(hdr.ifname));
262
263	if (am == NULL) {
264		hdr.rulenr = htonl(rm->nr);
265		hdr.subrulenr = -1;
266	} else {
267		hdr.rulenr = htonl(am->nr);
268		hdr.subrulenr = htonl(rm->nr);
269		if (ruleset != NULL && ruleset->anchor != NULL)
270			strlcpy(hdr.ruleset, ruleset->anchor->name,
271			    sizeof(hdr.ruleset));
272	}
273	if (rm->log & PF_LOG_SOCKET_LOOKUP && !pd->lookup.done)
274		pd->lookup.done = pf_socket_lookup(dir, pd);
275	if (pd->lookup.done > 0) {
276		hdr.uid = pd->lookup.uid;
277		hdr.pid = pd->lookup.pid;
278	} else {
279		hdr.uid = UID_MAX;
280		hdr.pid = NO_PID;
281	}
282	hdr.rule_uid = rm->cuid;
283	hdr.rule_pid = rm->cpid;
284	hdr.dir = dir;
285
286#ifdef INET
287	if (af == AF_INET && dir == PF_OUT) {
288		struct ip *ip;
289
290		ip = mtod(m, struct ip *);
291		ip->ip_sum = 0;
292		ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
293	}
294#endif /* INET */
295
296	ifn->if_opackets++;
297	ifn->if_obytes += m->m_pkthdr.len;
298
299#ifdef __NetBSD__
300	bpf_mtap2(ifn->if_bpf, &hdr, PFLOG_HDRLEN, m);
301#else
302	bpf_mtap_hdr(ifn->if_bpf, (char *)&hdr, PFLOG_HDRLEN, m,
303	    BPF_DIRECTION_OUT);
304#endif /* !__NetBSD__ */
305
306
307	return (0);
308}
309