1 /*
2 * Copyright (c) 2007-2023 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 #if !XNU_TARGET_OS_OSX
138
139 static const char *
findsubstr(const char * haystack,const char * needle,size_t needle_len)140 findsubstr(const char * haystack, const char * needle, size_t needle_len)
141 {
142 const char * scan;
143
144 for (scan = haystack; *scan != '\0'; scan++) {
145 if (strncmp(scan, needle, needle_len) == 0) {
146 return scan;
147 }
148 }
149 return NULL;
150 }
151
152 extern char osreleasetype[];
153
154 #define MY_OS_RELEASE_TYPE_MATCHES(str) (findsubstr(osreleasetype, str, sizeof(str) - 1) != NULL)
155
156 #define _DARWIN "Darwin"
157 #define _RESTORE "Restore"
158 #define _INTERNAL "Internal"
159 #define _NONUI "NonUI"
160
161 static inline bool
pflog_is_enabled(void)162 pflog_is_enabled(void)
163 {
164 uint8_t flags;
165 static uint8_t pflog_enabled_flags;
166
167 #define _FLAGS_INITIALIZED 0x1
168 #define _FLAGS_ENABLED 0x2
169
170 if (pflog_enabled_flags != 0) {
171 goto done;
172 }
173 flags = _FLAGS_INITIALIZED;
174 if (MY_OS_RELEASE_TYPE_MATCHES(_DARWIN) ||
175 MY_OS_RELEASE_TYPE_MATCHES(_RESTORE) ||
176 MY_OS_RELEASE_TYPE_MATCHES(_INTERNAL) ||
177 MY_OS_RELEASE_TYPE_MATCHES(_NONUI)) {
178 flags |= _FLAGS_ENABLED;
179 } else {
180 printf("%s: osreleasetype %s doesn't allow pflog\n", __func__,
181 osreleasetype);
182 }
183 lck_rw_lock_exclusive(&pf_perim_lock);
184 pflog_enabled_flags = flags;
185 lck_rw_done(&pf_perim_lock);
186
187 done:
188 return (pflog_enabled_flags & _FLAGS_ENABLED) != 0;
189 }
190
191 #endif /* !XNU_TARGET_OS_OSX */
192
193 static int
pflog_clone_create(struct if_clone * ifc,u_int32_t unit,__unused void * params)194 pflog_clone_create(struct if_clone *ifc, u_int32_t unit, __unused void *params)
195 {
196 struct pflog_softc *pflogif;
197 struct ifnet_init_eparams pf_init;
198 int error = 0;
199
200 #if !XNU_TARGET_OS_OSX
201 if (!pflog_is_enabled()) {
202 return EOPNOTSUPP;
203 }
204 #endif /* !XNU_TARGET_OS_OSX */
205
206 if (unit >= PFLOGIFS_MAX) {
207 /* Either the interface cloner or our initializer is broken */
208 panic("%s: unit (%d) exceeds max (%d)", __func__, unit,
209 PFLOGIFS_MAX);
210 /* NOTREACHED */
211 }
212
213 pflogif = kalloc_type(struct pflog_softc, Z_WAITOK_ZERO_NOFAIL);
214
215 bzero(&pf_init, sizeof(pf_init));
216 pf_init.ver = IFNET_INIT_CURRENT_VERSION;
217 pf_init.len = sizeof(pf_init);
218 pf_init.flags = IFNET_INIT_LEGACY;
219 pf_init.name = ifc->ifc_name;
220 pf_init.unit = unit;
221 pf_init.type = IFT_PFLOG;
222 pf_init.family = IFNET_FAMILY_LOOPBACK;
223 pf_init.output = pflogoutput;
224 pf_init.demux = pflogdemux;
225 pf_init.add_proto = pflogaddproto;
226 pf_init.del_proto = pflogdelproto;
227 pf_init.softc = pflogif;
228 pf_init.ioctl = pflogioctl;
229 pf_init.detach = pflogfree;
230
231 pflogif->sc_unit = unit;
232 pflogif->sc_flags |= IFPFLF_DETACHING;
233
234 error = ifnet_allocate_extended(&pf_init, &pflogif->sc_if);
235 if (error != 0) {
236 printf("%s: ifnet_allocate failed - %d\n", __func__, error);
237 kfree_type(struct pflog_softc, pflogif);
238 goto done;
239 }
240
241 ifnet_set_mtu(pflogif->sc_if, PFLOGMTU);
242 ifnet_set_flags(pflogif->sc_if, IFF_UP, IFF_UP);
243
244 error = ifnet_attach(pflogif->sc_if, NULL);
245 if (error != 0) {
246 printf("%s: ifnet_attach failed - %d\n", __func__, error);
247 ifnet_release(pflogif->sc_if);
248 kfree_type(struct pflog_softc, pflogif);
249 goto done;
250 }
251
252 #if NBPFILTER > 0
253 bpfattach(pflogif->sc_if, DLT_PFLOG, PFLOG_HDRLEN);
254 #endif
255
256 lck_rw_lock_shared(&pf_perim_lock);
257 lck_mtx_lock(&pf_lock);
258 LIST_INSERT_HEAD(&pflogif_list, pflogif, sc_list);
259 pflogifs[unit] = pflogif->sc_if;
260 pflogif->sc_flags &= ~IFPFLF_DETACHING;
261 lck_mtx_unlock(&pf_lock);
262 lck_rw_done(&pf_perim_lock);
263
264 done:
265 return error;
266 }
267
268 static int
pflog_remove(struct ifnet * ifp)269 pflog_remove(struct ifnet *ifp)
270 {
271 int error = 0;
272 struct pflog_softc *pflogif = NULL;
273
274 lck_rw_lock_shared(&pf_perim_lock);
275 lck_mtx_lock(&pf_lock);
276 pflogif = ifp->if_softc;
277
278 if (pflogif == NULL ||
279 (pflogif->sc_flags & IFPFLF_DETACHING) != 0) {
280 error = EINVAL;
281 goto done;
282 }
283
284 pflogif->sc_flags |= IFPFLF_DETACHING;
285 LIST_REMOVE(pflogif, sc_list);
286 done:
287 lck_mtx_unlock(&pf_lock);
288 lck_rw_done(&pf_perim_lock);
289 return error;
290 }
291
292 static int
pflog_clone_destroy(struct ifnet * ifp)293 pflog_clone_destroy(struct ifnet *ifp)
294 {
295 int error = 0;
296
297 if ((error = pflog_remove(ifp)) != 0) {
298 goto done;
299 }
300 /* bpfdetach() is taken care of as part of interface detach */
301 (void)ifnet_detach(ifp);
302 done:
303 return error;
304 }
305
306 static errno_t
pflogoutput(struct ifnet * ifp,struct mbuf * m)307 pflogoutput(struct ifnet *ifp, struct mbuf *m)
308 {
309 printf("%s: freeing data for %s\n", __func__, if_name(ifp));
310 m_freem(m);
311 return ENOTSUP;
312 }
313
314 static errno_t
pflogioctl(struct ifnet * ifp,unsigned long cmd,void * data)315 pflogioctl(struct ifnet *ifp, unsigned long cmd, void *data)
316 {
317 #pragma unused(data)
318 switch (cmd) {
319 case SIOCSIFADDR:
320 case SIOCAIFADDR:
321 case SIOCSIFDSTADDR:
322 case SIOCSIFFLAGS:
323 if (ifnet_flags(ifp) & IFF_UP) {
324 ifnet_set_flags(ifp, IFF_RUNNING, IFF_RUNNING);
325 } else {
326 ifnet_set_flags(ifp, 0, IFF_RUNNING);
327 }
328 break;
329 default:
330 return ENOTTY;
331 }
332
333 return 0;
334 }
335
336 static errno_t
pflogdemux(struct ifnet * ifp,struct mbuf * m,char * h,protocol_family_t * ppf)337 pflogdemux(struct ifnet *ifp, struct mbuf *m, char *h, protocol_family_t *ppf)
338 {
339 #pragma unused(h, ppf)
340 printf("%s: freeing data for %s\n", __func__, if_name(ifp));
341 m_freem(m);
342 return EJUSTRETURN;
343 }
344
345 static errno_t
pflogaddproto(struct ifnet * ifp,protocol_family_t pf,const struct ifnet_demux_desc * d,u_int32_t cnt)346 pflogaddproto(struct ifnet *ifp, protocol_family_t pf,
347 const struct ifnet_demux_desc *d, u_int32_t cnt)
348 {
349 #pragma unused(ifp, pf, d, cnt)
350 return 0;
351 }
352
353 static errno_t
pflogdelproto(struct ifnet * ifp,protocol_family_t pf)354 pflogdelproto(struct ifnet *ifp, protocol_family_t pf)
355 {
356 #pragma unused(ifp, pf)
357 return 0;
358 }
359
360 static void
pflogfree(struct ifnet * ifp)361 pflogfree(struct ifnet *ifp)
362 {
363 kfree_type(struct pflog_softc, ifp->if_softc);
364 ifp->if_softc = NULL;
365 (void) ifnet_release(ifp);
366 }
367
368 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)369 pflog_packet(struct pfi_kif *kif, pbuf_t *pbuf, sa_family_t af, u_int8_t dir,
370 u_int8_t reason, struct pf_rule *rm, struct pf_rule *am,
371 struct pf_ruleset *ruleset, struct pf_pdesc *pd)
372 {
373 #if NBPFILTER > 0
374 struct ifnet *ifn;
375 struct pfloghdr hdr;
376 struct mbuf *m;
377
378 LCK_MTX_ASSERT(&pf_lock, LCK_MTX_ASSERT_OWNED);
379
380 if (kif == NULL || !pbuf_is_valid(pbuf) || rm == NULL || pd == NULL) {
381 return -1;
382 }
383
384 if (rm->logif >= PFLOGIFS_MAX ||
385 (ifn = pflogifs[rm->logif]) == NULL || !ifn->if_bpf) {
386 return 0;
387 }
388
389 if ((m = pbuf_to_mbuf(pbuf, FALSE)) == NULL) {
390 return 0;
391 }
392
393 bzero(&hdr, sizeof(hdr));
394 hdr.length = PFLOG_REAL_HDRLEN;
395 hdr.af = af;
396 hdr.action = rm->action;
397 hdr.reason = reason;
398 memcpy(hdr.ifname, kif->pfik_name, sizeof(hdr.ifname));
399
400 if (am == NULL) {
401 hdr.rulenr = htonl(rm->nr);
402 hdr.subrulenr = -1;
403 } else {
404 hdr.rulenr = htonl(am->nr);
405 hdr.subrulenr = htonl(rm->nr);
406 if (ruleset != NULL && ruleset->anchor != NULL) {
407 strlcpy(hdr.ruleset, ruleset->anchor->name,
408 sizeof(hdr.ruleset));
409 }
410 }
411 if (rm->log & PF_LOG_SOCKET_LOOKUP && !pd->lookup.done) {
412 pd->lookup.done = pf_socket_lookup(dir, pd);
413 }
414 if (pd->lookup.done > 0) {
415 hdr.uid = pd->lookup.uid;
416 hdr.pid = pd->lookup.pid;
417 } else {
418 hdr.uid = UID_MAX;
419 hdr.pid = NO_PID;
420 }
421 hdr.rule_uid = rm->cuid;
422 hdr.rule_pid = rm->cpid;
423 hdr.dir = dir;
424
425 #if INET
426 if (af == AF_INET && dir == PF_OUT) {
427 struct ip *ip;
428
429 ip = mtod(m, struct ip *);
430 ip->ip_sum = 0;
431 ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
432 }
433 #endif /* INET */
434
435 os_atomic_inc(&ifn->if_opackets, relaxed);
436 os_atomic_add(&ifn->if_obytes, m->m_pkthdr.len, relaxed);
437
438 switch (dir) {
439 case PF_IN:
440 bpf_tap_in(ifn, DLT_PFLOG, m, &hdr, PFLOG_HDRLEN);
441 break;
442
443 case PF_OUT:
444 bpf_tap_out(ifn, DLT_PFLOG, m, &hdr, PFLOG_HDRLEN);
445 break;
446
447 default:
448 break;
449 }
450 #endif /* NBPFILTER > 0 */
451 return 0;
452 }
453