xref: /dflybsd-src/sys/net/pf/if_pflog.c (revision a9656fbcd49c376aba5e04370d8b0f1fa96e063c)
1 /*	$FreeBSD: src/sys/contrib/pf/net/if_pflog.c,v 1.9 2004/06/22 20:13:24 brooks Exp $	*/
2 /*	$OpenBSD: if_pflog.c,v 1.11 2003/12/31 11:18:25 cedric Exp $	*/
3 /*	$DragonFly: src/sys/net/pf/if_pflog.c,v 1.6 2006/12/22 23:44:57 swildner Exp $ */
4 /*	$OpenBSD: if_pflog.c,v 1.22 2006/12/15 09:31:20 otto Exp $	*/
5 /*
6  * The authors of this code are John Ioannidis (ji@tla.org),
7  * Angelos D. Keromytis (kermit@csd.uch.gr) and
8  * Niels Provos (provos@physnet.uni-hamburg.de).
9  *
10  * This code was written by John Ioannidis for BSD/OS in Athens, Greece,
11  * in November 1995.
12  *
13  * Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
14  * by Angelos D. Keromytis.
15  *
16  * Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis
17  * and Niels Provos.
18  *
19  * Copyright (C) 1995, 1996, 1997, 1998 by John Ioannidis, Angelos D. Keromytis
20  * and Niels Provos.
21  * Copyright (c) 2001, Angelos D. Keromytis, Niels Provos.
22  *
23  * Copyright (c) 2004 The DragonFly Project.  All rights reserved.
24  *
25  * Permission to use, copy, and modify this software with or without fee
26  * is hereby granted, provided that this entire notice is included in
27  * all copies of any software which is or includes a copy or
28  * modification of this software.
29  * You may use this code under the GNU public license if you so wish. Please
30  * contribute changes back to the authors under this freer than GPL license
31  * so that we may further the use of strong encryption without limitations to
32  * all.
33  *
34  * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
35  * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
36  * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
37  * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
38  * PURPOSE.
39  */
40 
41 #include "opt_inet.h"
42 #include "opt_inet6.h"
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/in_cksum.h>
47 #include <sys/mbuf.h>
48 #include <sys/proc.h>
49 #include <sys/socket.h>
50 #include <sys/kernel.h>
51 #include <sys/malloc.h>
52 #include <sys/module.h>
53 #include <sys/sockio.h>
54 #include <sys/thread2.h>
55 #include <vm/vm_zone.h>
56 
57 #include <net/if.h>
58 #include <net/if_types.h>
59 #include <net/route.h>
60 #include <net/bpf.h>
61 
62 #ifdef	INET
63 #include <netinet/in.h>
64 #include <netinet/in_var.h>
65 #include <netinet/in_systm.h>
66 #include <netinet/ip.h>
67 #endif
68 
69 #ifdef INET6
70 #ifndef INET
71 #include <netinet/in.h>
72 #endif
73 #include <netinet6/nd6.h>
74 #endif /* INET6 */
75 
76 #include <net/pf/pfvar.h>
77 #include <net/pf/if_pflog.h>
78 
79 #define	PFLOGNAME	"pflog"
80 
81 #define PFLOGMTU	(32768 + MHLEN + MLEN)
82 
83 #ifdef PFLOGDEBUG
84 #define DPRINTF(x)    do { if (pflogdebug) kprintf x ; } while (0)
85 #else
86 #define DPRINTF(x)
87 #endif
88 
89 void	pflogattach(int);
90 int	pflogoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
91 	    	       struct rtentry *);
92 int	pflogioctl(struct ifnet *, u_long, caddr_t, struct ucred *);
93 void	pflogrtrequest(int, struct rtentry *, struct sockaddr *);
94 void	pflogstart(struct ifnet *);
95 
96 int	pflog_clone_create(struct if_clone *, int, caddr_t);
97 void pflog_clone_destroy(struct ifnet *);
98 
99 LIST_HEAD(, pflog_softc)	pflogif_list;
100 struct if_clone	pflog_cloner =
101     IF_CLONE_INITIALIZER("pflog", pflog_clone_create, pflog_clone_destroy, 1, 1);
102 
103 struct ifnet	*pflogifs[PFLOGIFS_MAX];	/* for fast access */
104 
105 void
106 pflogattach(int npflog)
107 {
108 	int	i;
109 	LIST_INIT(&pflogif_list);
110 	for (i = 0; i < PFLOGIFS_MAX; i++)
111 		pflogifs[i] = NULL;
112 	(void) pflog_clone_create(&pflog_cloner, 0, NULL);
113 	if_clone_attach(&pflog_cloner);
114 }
115 
116 int
117 pflog_clone_create(struct if_clone *ifc, int unit, caddr_t param __unused)
118 {
119 	struct ifnet *ifp;
120 	struct pflog_softc *pflogif;
121 
122 	if (unit >= PFLOGIFS_MAX)
123 		return (EINVAL);
124 
125 	if ((pflogif = kmalloc(sizeof(*pflogif), M_DEVBUF, M_WAITOK)) == NULL)
126 		return (ENOMEM);
127 	bzero(pflogif, sizeof(*pflogif));
128 
129 	pflogif->sc_unit = unit;
130 	ifp = &pflogif->sc_if;
131 	ksnprintf(ifp->if_xname, sizeof ifp->if_xname, "pflog%d", unit);
132 	ifp->if_softc = pflogif;
133 	ifp->if_mtu = PFLOGMTU;
134 	ifp->if_ioctl = pflogioctl;
135 	ifp->if_output = pflogoutput;
136 	ifp->if_start = pflogstart;
137 	ifp->if_type = IFT_PFLOG;
138 	ifp->if_snd.ifq_maxlen = ifqmaxlen;
139 	ifp->if_hdrlen = PFLOG_HDRLEN;
140 	if_attach(ifp, NULL);
141 
142 	bpfattach(&pflogif->sc_if, DLT_PFLOG, PFLOG_HDRLEN);
143 
144 	crit_enter();
145 	LIST_INSERT_HEAD(&pflogif_list, pflogif, sc_list);
146 	pflogifs[unit] = ifp;
147 	crit_exit();
148 
149 	return (0);
150 }
151 
152 void
153 pflog_clone_destroy(struct ifnet *ifp)
154 {
155 	struct pflog_softc	*pflogif = ifp->if_softc;
156 
157 	crit_enter();
158 	pflogifs[pflogif->sc_unit] = NULL;
159 	LIST_REMOVE(pflogif, sc_list);
160 	crit_exit();
161 
162 #if NBPFILTER > 0
163 	bpfdetach(ifp);
164 #endif
165 	if_detach(ifp);
166 	kfree(pflogif, M_DEVBUF);
167 }
168 
169 /*
170  * Start output on the pflog interface.
171  */
172 void
173 pflogstart(struct ifnet *ifp)
174 {
175 	struct mbuf *m;
176 
177 	for (;;) {
178 		crit_enter();
179 		IF_DROP(&ifp->if_snd);
180 		IF_DEQUEUE(&ifp->if_snd, m);
181 		crit_exit();
182 
183 		if (m == NULL)
184 			return;
185 		else
186 			m_freem(m);
187 	}
188 }
189 
190 int
191 pflogoutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
192 	struct rtentry *rt)
193 {
194 	m_freem(m);
195 	return (0);
196 }
197 
198 /* ARGSUSED */
199 void
200 pflogrtrequest(int cmd, struct rtentry *rt, struct sockaddr *sa)
201 {
202 	if (rt)
203 		rt->rt_rmx.rmx_mtu = PFLOGMTU;
204 }
205 
206 /* ARGSUSED */
207 int
208 pflogioctl(struct ifnet *ifp, u_long cmd, caddr_t data, struct ucred *cr)
209 {
210 	switch (cmd) {
211 	case SIOCSIFADDR:
212 	case SIOCAIFADDR:
213 	case SIOCSIFDSTADDR:
214 	case SIOCSIFFLAGS:
215 		if (ifp->if_flags & IFF_UP)
216 			ifp->if_flags |= IFF_RUNNING;
217 		else
218 			ifp->if_flags &= ~IFF_RUNNING;
219 		break;
220 	default:
221 		return (EINVAL);
222 	}
223 
224 	return (0);
225 }
226 
227 int
228 pflog_packet(struct pfi_kif *kif, struct mbuf *m, sa_family_t af, u_int8_t dir,
229     u_int8_t reason, struct pf_rule *rm, struct pf_rule *am,
230     struct pf_ruleset *ruleset, struct pf_pdesc *pd)
231 {
232 	struct ifnet *ifn = NULL;
233 	struct pfloghdr hdr;
234 
235 	if (kif == NULL || m == NULL || rm == NULL)
236 		return (-1);
237 
238 	if ((ifn = pflogifs[rm->logif]) == NULL || !ifn->if_bpf)
239 		return (0);
240 
241 	bzero(&hdr, sizeof(hdr));
242 	hdr.length = PFLOG_REAL_HDRLEN;
243 	hdr.af = af;
244 	hdr.action = rm->action;
245 	hdr.reason = reason;
246 	memcpy(hdr.ifname, kif->pfik_name, sizeof(hdr.ifname));
247 
248 	if (am == NULL) {
249 		hdr.rulenr = htonl(rm->nr);
250 		hdr.subrulenr = -1;
251 	} else {
252 		hdr.rulenr = htonl(am->nr);
253 		hdr.subrulenr = htonl(rm->nr);
254 		if (ruleset != NULL && ruleset->anchor != NULL) {
255 			strlcpy(hdr.ruleset, ruleset->anchor->name,
256 			    sizeof(hdr.ruleset));
257 		}
258 	}
259 	if (rm->log & PF_LOG_SOCKET_LOOKUP && !pd->lookup.done)
260 		pd->lookup.done = pf_socket_lookup(dir, pd, NULL);
261 	if (pd->lookup.done > 0) {
262 		hdr.uid = pd->lookup.uid;
263 		hdr.pid = pd->lookup.pid;
264 	} else {
265 		hdr.uid = UID_MAX;
266 		hdr.pid = NO_PID;
267 	}
268 	hdr.rule_uid = rm->cuid;
269 	hdr.rule_pid = rm->cpid;
270 	hdr.dir = dir;
271 
272 #ifdef INET
273 	if (af == AF_INET) {
274 		struct ip *ip;
275 		ip = mtod(m, struct ip *);
276 		ip->ip_len = htons(ip->ip_len);
277 		ip->ip_off = htons(ip->ip_off);
278 
279 		if (dir == PF_OUT) {
280 			ip->ip_sum = 0;
281 			ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
282 		}
283 	}
284 #endif /* INET */
285 
286 	ifn->if_opackets++;
287 	ifn->if_obytes += m->m_pkthdr.len;
288 	bpf_mtap_hdr(ifn->if_bpf, (char *)&hdr, PFLOG_HDRLEN, m,
289 	    BPF_DIRECTION_OUT);
290 
291 #ifdef INET
292 	if (af == AF_INET) {
293 		struct ip *ip = mtod(m, struct ip *);
294 
295 		ip->ip_len = ntohs(ip->ip_len);
296 		ip->ip_off = ntohs(ip->ip_off);
297 	}
298 #endif /* INET */
299 
300 	return (0);
301 }
302 
303 static int
304 pflog_modevent(module_t mod, int type, void *data)
305 {
306 	int error = 0;
307 
308 	switch (type) {
309 	case MOD_LOAD:
310 		LIST_INIT(&pflogif_list);
311 		if_clone_attach(&pflog_cloner);
312 		break;
313 
314 	case MOD_UNLOAD:
315 		if_clone_detach(&pflog_cloner);
316 		while (!LIST_EMPTY(&pflogif_list)) {
317 			pflog_clone_destroy(
318 				&LIST_FIRST(&pflogif_list)->sc_if);
319 		}
320 		break;
321 
322 	default:
323 		error = EINVAL;
324 		break;
325 	}
326 
327 	return error;
328 }
329 
330 static moduledata_t pflog_mod = {
331 	"pflog",
332 	pflog_modevent,
333 	0
334 };
335 
336 #define PFLOG_MODVER 1
337 
338 DECLARE_MODULE(pflog, pflog_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
339 MODULE_VERSION(pflog, PFLOG_MODVER);
340