xref: /xnu-8796.101.5/bsd/net/if_pflog.c (revision aca3beaa3dfbd42498b42c5e5ce20a938e6554e5)
1 /*
2  * Copyright (c) 2007-2018 Apple Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
7  * as defined in and that are subject to the Apple Public Source License
8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23  * Please see the License for the specific language governing rights and
24  * limitations under the License.
25  *
26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27  */
28 
29 /*	$apfw: if_pflog.c,v 1.4 2008/08/27 00:01:32 jhw Exp $		*/
30 /*	$OpenBSD: if_pflog.c,v 1.22 2006/12/15 09:31:20 otto Exp $	*/
31 /*
32  * The authors of this code are John Ioannidis ([email protected]),
33  * Angelos D. Keromytis ([email protected]) and
34  * Niels Provos ([email protected]).
35  *
36  * This code was written by John Ioannidis for BSD/OS in Athens, Greece,
37  * in November 1995.
38  *
39  * Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
40  * by Angelos D. Keromytis.
41  *
42  * Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis
43  * and Niels Provos.
44  *
45  * Copyright (C) 1995, 1996, 1997, 1998 by John Ioannidis, Angelos D. Keromytis
46  * and Niels Provos.
47  * Copyright (c) 2001, Angelos D. Keromytis, Niels Provos.
48  *
49  * Permission to use, copy, and modify this software with or without fee
50  * is hereby granted, provided that this entire notice is included in
51  * all copies of any software which is or includes a copy or
52  * modification of this software.
53  * You may use this code under the GNU public license if you so wish. Please
54  * contribute changes back to the authors under this freer than GPL license
55  * so that we may further the use of strong encryption without limitations to
56  * all.
57  *
58  * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
59  * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
60  * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
61  * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
62  * PURPOSE.
63  */
64 
65 #include <sys/param.h>
66 #include <sys/systm.h>
67 #include <sys/mbuf.h>
68 #include <sys/proc_internal.h>
69 #include <sys/socket.h>
70 #include <sys/ioctl.h>
71 #include <sys/mcache.h>
72 
73 #include <kern/zalloc.h>
74 
75 #include <net/if.h>
76 #include <net/if_var.h>
77 #include <net/if_types.h>
78 #include <net/route.h>
79 #include <net/bpf.h>
80 
81 #if INET
82 #include <netinet/in.h>
83 #include <netinet/in_var.h>
84 #include <netinet/in_systm.h>
85 #include <netinet/ip.h>
86 #endif
87 
88 #if !INET
89 #include <netinet/in.h>
90 #endif
91 #include <netinet6/nd6.h>
92 
93 #include <net/pfvar.h>
94 #include <net/if_pflog.h>
95 
96 #define PFLOGNAME       "pflog"
97 #define PFLOGMTU        (32768 + MHLEN + MLEN)
98 
99 #ifdef PFLOGDEBUG
100 #define DPRINTF(x)    do { if (pflogdebug) printf x ; } while (0)
101 #else
102 #define DPRINTF(x)
103 #endif
104 
105 static int pflog_remove(struct ifnet *);
106 static int pflog_clone_create(struct if_clone *, u_int32_t, void *);
107 static int pflog_clone_destroy(struct ifnet *);
108 static errno_t pflogoutput(struct ifnet *, struct mbuf *);
109 static errno_t pflogioctl(struct ifnet *, unsigned long, void *);
110 static errno_t pflogdemux(struct ifnet *, struct mbuf *, char *,
111     protocol_family_t *);
112 static errno_t pflogaddproto(struct ifnet *, protocol_family_t,
113     const struct ifnet_demux_desc *, u_int32_t);
114 static errno_t pflogdelproto(struct ifnet *, protocol_family_t);
115 static void pflogfree(struct ifnet *);
116 
117 static LIST_HEAD(, pflog_softc) pflogif_list;
118 static struct if_clone pflog_cloner =
119     IF_CLONE_INITIALIZER(PFLOGNAME, pflog_clone_create, pflog_clone_destroy,
120     0, (PFLOGIFS_MAX - 1));
121 
122 struct ifnet *pflogifs[PFLOGIFS_MAX];   /* for fast access */
123 
124 void
pfloginit(void)125 pfloginit(void)
126 {
127 	int i;
128 
129 	LIST_INIT(&pflogif_list);
130 	for (i = 0; i < PFLOGIFS_MAX; i++) {
131 		pflogifs[i] = NULL;
132 	}
133 
134 	(void) if_clone_attach(&pflog_cloner);
135 }
136 
137 static int
pflog_clone_create(struct if_clone * ifc,u_int32_t unit,__unused void * params)138 pflog_clone_create(struct if_clone *ifc, u_int32_t unit, __unused void *params)
139 {
140 	struct pflog_softc *pflogif;
141 	struct ifnet_init_eparams pf_init;
142 	int error = 0;
143 
144 	if (unit >= PFLOGIFS_MAX) {
145 		/* Either the interface cloner or our initializer is broken */
146 		panic("%s: unit (%d) exceeds max (%d)", __func__, unit,
147 		    PFLOGIFS_MAX);
148 		/* NOTREACHED */
149 	}
150 
151 	pflogif = kalloc_type(struct pflog_softc, Z_WAITOK_ZERO_NOFAIL);
152 
153 	bzero(&pf_init, sizeof(pf_init));
154 	pf_init.ver = IFNET_INIT_CURRENT_VERSION;
155 	pf_init.len = sizeof(pf_init);
156 	pf_init.flags = IFNET_INIT_LEGACY;
157 	pf_init.name = ifc->ifc_name;
158 	pf_init.unit = unit;
159 	pf_init.type = IFT_PFLOG;
160 	pf_init.family = IFNET_FAMILY_LOOPBACK;
161 	pf_init.output = pflogoutput;
162 	pf_init.demux = pflogdemux;
163 	pf_init.add_proto = pflogaddproto;
164 	pf_init.del_proto = pflogdelproto;
165 	pf_init.softc = pflogif;
166 	pf_init.ioctl = pflogioctl;
167 	pf_init.detach = pflogfree;
168 
169 	pflogif->sc_unit = unit;
170 	pflogif->sc_flags |= IFPFLF_DETACHING;
171 
172 	error = ifnet_allocate_extended(&pf_init, &pflogif->sc_if);
173 	if (error != 0) {
174 		printf("%s: ifnet_allocate failed - %d\n", __func__, error);
175 		kfree_type(struct pflog_softc, pflogif);
176 		goto done;
177 	}
178 
179 	ifnet_set_mtu(pflogif->sc_if, PFLOGMTU);
180 	ifnet_set_flags(pflogif->sc_if, IFF_UP, IFF_UP);
181 
182 	error = ifnet_attach(pflogif->sc_if, NULL);
183 	if (error != 0) {
184 		printf("%s: ifnet_attach failed - %d\n", __func__, error);
185 		ifnet_release(pflogif->sc_if);
186 		kfree_type(struct pflog_softc, pflogif);
187 		goto done;
188 	}
189 
190 #if NBPFILTER > 0
191 	bpfattach(pflogif->sc_if, DLT_PFLOG, PFLOG_HDRLEN);
192 #endif
193 
194 	lck_rw_lock_shared(&pf_perim_lock);
195 	lck_mtx_lock(&pf_lock);
196 	LIST_INSERT_HEAD(&pflogif_list, pflogif, sc_list);
197 	pflogifs[unit] = pflogif->sc_if;
198 	pflogif->sc_flags &= ~IFPFLF_DETACHING;
199 	lck_mtx_unlock(&pf_lock);
200 	lck_rw_done(&pf_perim_lock);
201 
202 done:
203 	return error;
204 }
205 
206 static int
pflog_remove(struct ifnet * ifp)207 pflog_remove(struct ifnet *ifp)
208 {
209 	int error = 0;
210 	struct pflog_softc *pflogif = NULL;
211 
212 	lck_rw_lock_shared(&pf_perim_lock);
213 	lck_mtx_lock(&pf_lock);
214 	pflogif = ifp->if_softc;
215 
216 	if (pflogif == NULL ||
217 	    (pflogif->sc_flags & IFPFLF_DETACHING) != 0) {
218 		error = EINVAL;
219 		goto done;
220 	}
221 
222 	pflogif->sc_flags |= IFPFLF_DETACHING;
223 	LIST_REMOVE(pflogif, sc_list);
224 done:
225 	lck_mtx_unlock(&pf_lock);
226 	lck_rw_done(&pf_perim_lock);
227 	return error;
228 }
229 
230 static int
pflog_clone_destroy(struct ifnet * ifp)231 pflog_clone_destroy(struct ifnet *ifp)
232 {
233 	int error = 0;
234 
235 	if ((error = pflog_remove(ifp)) != 0) {
236 		goto done;
237 	}
238 	/* bpfdetach() is taken care of as part of interface detach */
239 	(void)ifnet_detach(ifp);
240 done:
241 	return error;
242 }
243 
244 static errno_t
pflogoutput(struct ifnet * ifp,struct mbuf * m)245 pflogoutput(struct ifnet *ifp, struct mbuf *m)
246 {
247 	printf("%s: freeing data for %s\n", __func__, if_name(ifp));
248 	m_freem(m);
249 	return ENOTSUP;
250 }
251 
252 static errno_t
pflogioctl(struct ifnet * ifp,unsigned long cmd,void * data)253 pflogioctl(struct ifnet *ifp, unsigned long cmd, void *data)
254 {
255 #pragma unused(data)
256 	switch (cmd) {
257 	case SIOCSIFADDR:
258 	case SIOCAIFADDR:
259 	case SIOCSIFDSTADDR:
260 	case SIOCSIFFLAGS:
261 		if (ifnet_flags(ifp) & IFF_UP) {
262 			ifnet_set_flags(ifp, IFF_RUNNING, IFF_RUNNING);
263 		} else {
264 			ifnet_set_flags(ifp, 0, IFF_RUNNING);
265 		}
266 		break;
267 	default:
268 		return ENOTTY;
269 	}
270 
271 	return 0;
272 }
273 
274 static errno_t
pflogdemux(struct ifnet * ifp,struct mbuf * m,char * h,protocol_family_t * ppf)275 pflogdemux(struct ifnet *ifp, struct mbuf *m, char *h, protocol_family_t *ppf)
276 {
277 #pragma unused(h, ppf)
278 	printf("%s: freeing data for %s\n", __func__, if_name(ifp));
279 	m_freem(m);
280 	return EJUSTRETURN;
281 }
282 
283 static errno_t
pflogaddproto(struct ifnet * ifp,protocol_family_t pf,const struct ifnet_demux_desc * d,u_int32_t cnt)284 pflogaddproto(struct ifnet *ifp, protocol_family_t pf,
285     const struct ifnet_demux_desc *d, u_int32_t cnt)
286 {
287 #pragma unused(ifp, pf, d, cnt)
288 	return 0;
289 }
290 
291 static errno_t
pflogdelproto(struct ifnet * ifp,protocol_family_t pf)292 pflogdelproto(struct ifnet *ifp, protocol_family_t pf)
293 {
294 #pragma unused(ifp, pf)
295 	return 0;
296 }
297 
298 static void
pflogfree(struct ifnet * ifp)299 pflogfree(struct ifnet *ifp)
300 {
301 	kfree_type(struct pflog_softc, ifp->if_softc);
302 	ifp->if_softc = NULL;
303 	(void) ifnet_release(ifp);
304 }
305 
306 int
pflog_packet(struct pfi_kif * kif,pbuf_t * pbuf,sa_family_t af,u_int8_t dir,u_int8_t reason,struct pf_rule * rm,struct pf_rule * am,struct pf_ruleset * ruleset,struct pf_pdesc * pd)307 pflog_packet(struct pfi_kif *kif, pbuf_t *pbuf, sa_family_t af, u_int8_t dir,
308     u_int8_t reason, struct pf_rule *rm, struct pf_rule *am,
309     struct pf_ruleset *ruleset, struct pf_pdesc *pd)
310 {
311 #if NBPFILTER > 0
312 	struct ifnet *ifn;
313 	struct pfloghdr hdr;
314 	struct mbuf *m;
315 
316 	LCK_MTX_ASSERT(&pf_lock, LCK_MTX_ASSERT_OWNED);
317 
318 	if (kif == NULL || !pbuf_is_valid(pbuf) || rm == NULL || pd == NULL) {
319 		return -1;
320 	}
321 
322 	if (rm->logif >= PFLOGIFS_MAX ||
323 	    (ifn = pflogifs[rm->logif]) == NULL || !ifn->if_bpf) {
324 		return 0;
325 	}
326 
327 	if ((m = pbuf_to_mbuf(pbuf, FALSE)) == NULL) {
328 		return 0;
329 	}
330 
331 	bzero(&hdr, sizeof(hdr));
332 	hdr.length = PFLOG_REAL_HDRLEN;
333 	hdr.af = af;
334 	hdr.action = rm->action;
335 	hdr.reason = reason;
336 	memcpy(hdr.ifname, kif->pfik_name, sizeof(hdr.ifname));
337 
338 	if (am == NULL) {
339 		hdr.rulenr = htonl(rm->nr);
340 		hdr.subrulenr = -1;
341 	} else {
342 		hdr.rulenr = htonl(am->nr);
343 		hdr.subrulenr = htonl(rm->nr);
344 		if (ruleset != NULL && ruleset->anchor != NULL) {
345 			strlcpy(hdr.ruleset, ruleset->anchor->name,
346 			    sizeof(hdr.ruleset));
347 		}
348 	}
349 	if (rm->log & PF_LOG_SOCKET_LOOKUP && !pd->lookup.done) {
350 		pd->lookup.done = pf_socket_lookup(dir, pd);
351 	}
352 	if (pd->lookup.done > 0) {
353 		hdr.uid = pd->lookup.uid;
354 		hdr.pid = pd->lookup.pid;
355 	} else {
356 		hdr.uid = UID_MAX;
357 		hdr.pid = NO_PID;
358 	}
359 	hdr.rule_uid = rm->cuid;
360 	hdr.rule_pid = rm->cpid;
361 	hdr.dir = dir;
362 
363 #if INET
364 	if (af == AF_INET && dir == PF_OUT) {
365 		struct ip *ip;
366 
367 		ip = mtod(m, struct ip *);
368 		ip->ip_sum = 0;
369 		ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
370 	}
371 #endif /* INET */
372 
373 	atomic_add_64(&ifn->if_opackets, 1);
374 	atomic_add_64(&ifn->if_obytes, m->m_pkthdr.len);
375 
376 	switch (dir) {
377 	case PF_IN:
378 		bpf_tap_in(ifn, DLT_PFLOG, m, &hdr, PFLOG_HDRLEN);
379 		break;
380 
381 	case PF_OUT:
382 		bpf_tap_out(ifn, DLT_PFLOG, m, &hdr, PFLOG_HDRLEN);
383 		break;
384 
385 	default:
386 		break;
387 	}
388 #endif /* NBPFILTER > 0 */
389 	return 0;
390 }
391