bsd/net/if_pflog.c

   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 (ji@tla.org),
  33  * Angelos D. Keromytis (kermit@csd.uch.gr) and
  34  * Niels Provos (provos@physnet.uni-hamburg.de).
  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), PFLOGIF_ZONE_MAX_ELEM, sizeof(struct pflog_softc));
 121
 122 struct ifnet *pflogifs[PFLOGIFS_MAX];   /* for fast access */
 123
 124 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
 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         if ((pflogif = if_clone_softc_allocate(&pflog_cloner)) == NULL) {
 152                 error = ENOMEM;
 153                 goto done;
 154         }
 155
 156         bzero(&pf_init, sizeof(pf_init));
 157         pf_init.ver = IFNET_INIT_CURRENT_VERSION;
 158         pf_init.len = sizeof(pf_init);
 159         pf_init.flags = IFNET_INIT_LEGACY;
 160         pf_init.name = ifc->ifc_name;
 161         pf_init.unit = unit;
 162         pf_init.type = IFT_PFLOG;
 163         pf_init.family = IFNET_FAMILY_LOOPBACK;
 164         pf_init.output = pflogoutput;
 165         pf_init.demux = pflogdemux;
 166         pf_init.add_proto = pflogaddproto;
 167         pf_init.del_proto = pflogdelproto;
 168         pf_init.softc = pflogif;
 169         pf_init.ioctl = pflogioctl;
 170         pf_init.detach = pflogfree;
 171
 172         bzero(pflogif, sizeof(*pflogif));
 173         pflogif->sc_unit = unit;
 174         pflogif->sc_flags |= IFPFLF_DETACHING;
 175
 176         error = ifnet_allocate_extended(&pf_init, &pflogif->sc_if);
 177         if (error != 0) {
 178                 printf("%s: ifnet_allocate failed - %d\n", __func__, error);
 179                 if_clone_softc_deallocate(&pflog_cloner, pflogif);
 180                 goto done;
 181         }
 182
 183         ifnet_set_mtu(pflogif->sc_if, PFLOGMTU);
 184         ifnet_set_flags(pflogif->sc_if, IFF_UP, IFF_UP);
 185
 186         error = ifnet_attach(pflogif->sc_if, NULL);
 187         if (error != 0) {
 188                 printf("%s: ifnet_attach failed - %d\n", __func__, error);
 189                 ifnet_release(pflogif->sc_if);
 190                 if_clone_softc_deallocate(&pflog_cloner, pflogif);
 191                 goto done;
 192         }
 193
 194 #if NBPFILTER > 0
 195         bpfattach(pflogif->sc_if, DLT_PFLOG, PFLOG_HDRLEN);
 196 #endif
 197
 198         lck_rw_lock_shared(pf_perim_lock);
 199         lck_mtx_lock(pf_lock);
 200         LIST_INSERT_HEAD(&pflogif_list, pflogif, sc_list);
 201         pflogifs[unit] = pflogif->sc_if;
 202         pflogif->sc_flags &= ~IFPFLF_DETACHING;
 203         lck_mtx_unlock(pf_lock);
 204         lck_rw_done(pf_perim_lock);
 205
 206 done:
 207         return error;
 208 }
 209
 210 static int
 211 pflog_remove(struct ifnet *ifp)
 212 {
 213         int error = 0;
 214         struct pflog_softc *pflogif = NULL;
 215
 216         lck_rw_lock_shared(pf_perim_lock);
 217         lck_mtx_lock(pf_lock);
 218         pflogif = ifp->if_softc;
 219
 220         if (pflogif == NULL ||
 221             (pflogif->sc_flags & IFPFLF_DETACHING) != 0) {
 222                 error = EINVAL;
 223                 goto done;
 224         }
 225
 226         pflogif->sc_flags |= IFPFLF_DETACHING;
 227         LIST_REMOVE(pflogif, sc_list);
 228 done:
 229         lck_mtx_unlock(pf_lock);
 230         lck_rw_done(pf_perim_lock);
 231         return error;
 232 }
 233
 234 static int
 235 pflog_clone_destroy(struct ifnet *ifp)
 236 {
 237         int error = 0;
 238
 239         if ((error = pflog_remove(ifp)) != 0) {
 240                 goto done;
 241         }
 242         /* bpfdetach() is taken care of as part of interface detach */
 243         (void)ifnet_detach(ifp);
 244 done:
 245         return error;
 246 }
 247
 248 static errno_t
 249 pflogoutput(struct ifnet *ifp, struct mbuf *m)
 250 {
 251         printf("%s: freeing data for %s\n", __func__, if_name(ifp));
 252         m_freem(m);
 253         return ENOTSUP;
 254 }
 255
 256 static errno_t
 257 pflogioctl(struct ifnet *ifp, unsigned long cmd, void *data)
 258 {
 259 #pragma unused(data)
 260         switch (cmd) {
 261         case SIOCSIFADDR:
 262         case SIOCAIFADDR:
 263         case SIOCSIFDSTADDR:
 264         case SIOCSIFFLAGS:
 265                 if (ifnet_flags(ifp) & IFF_UP) {
 266                         ifnet_set_flags(ifp, IFF_RUNNING, IFF_RUNNING);
 267                 } else {
 268                         ifnet_set_flags(ifp, 0, IFF_RUNNING);
 269                 }
 270                 break;
 271         default:
 272                 return ENOTTY;
 273         }
 274
 275         return 0;
 276 }
 277
 278 static errno_t
 279 pflogdemux(struct ifnet *ifp, struct mbuf *m, char *h, protocol_family_t *ppf)
 280 {
 281 #pragma unused(h, ppf)
 282         printf("%s: freeing data for %s\n", __func__, if_name(ifp));
 283         m_freem(m);
 284         return EJUSTRETURN;
 285 }
 286
 287 static errno_t
 288 pflogaddproto(struct ifnet *ifp, protocol_family_t pf,
 289     const struct ifnet_demux_desc *d, u_int32_t cnt)
 290 {
 291 #pragma unused(ifp, pf, d, cnt)
 292         return 0;
 293 }
 294
 295 static errno_t
 296 pflogdelproto(struct ifnet *ifp, protocol_family_t pf)
 297 {
 298 #pragma unused(ifp, pf)
 299         return 0;
 300 }
 301
 302 static void
 303 pflogfree(struct ifnet *ifp)
 304 {
 305         if_clone_softc_deallocate(&pflog_cloner, ifp->if_softc);
 306         ifp->if_softc = NULL;
 307         (void) ifnet_release(ifp);
 308 }
 309
 310 int
 311 pflog_packet(struct pfi_kif *kif, pbuf_t *pbuf, sa_family_t af, u_int8_t dir,
 312     u_int8_t reason, struct pf_rule *rm, struct pf_rule *am,
 313     struct pf_ruleset *ruleset, struct pf_pdesc *pd)
 314 {
 315 #if NBPFILTER > 0
 316         struct ifnet *ifn;
 317         struct pfloghdr hdr;
 318         struct mbuf *m;
 319
 320         LCK_MTX_ASSERT(pf_lock, LCK_MTX_ASSERT_OWNED);
 321
 322         if (kif == NULL || !pbuf_is_valid(pbuf) || rm == NULL || pd == NULL) {
 323                 return -1;
 324         }
 325
 326         if (rm->logif >= PFLOGIFS_MAX ||
 327             (ifn = pflogifs[rm->logif]) == NULL || !ifn->if_bpf) {
 328                 return 0;
 329         }
 330
 331         if ((m = pbuf_to_mbuf(pbuf, FALSE)) == NULL) {
 332                 return 0;
 333         }
 334
 335         bzero(&hdr, sizeof(hdr));
 336         hdr.length = PFLOG_REAL_HDRLEN;
 337         hdr.af = af;
 338         hdr.action = rm->action;
 339         hdr.reason = reason;
 340         memcpy(hdr.ifname, kif->pfik_name, sizeof(hdr.ifname));
 341
 342         if (am == NULL) {
 343                 hdr.rulenr = htonl(rm->nr);
 344                 hdr.subrulenr = -1;
 345         } else {
 346                 hdr.rulenr = htonl(am->nr);
 347                 hdr.subrulenr = htonl(rm->nr);
 348                 if (ruleset != NULL && ruleset->anchor != NULL) {
 349                         strlcpy(hdr.ruleset, ruleset->anchor->name,
 350                             sizeof(hdr.ruleset));
 351                 }
 352         }
 353         if (rm->log & PF_LOG_SOCKET_LOOKUP && !pd->lookup.done) {
 354                 pd->lookup.done = pf_socket_lookup(dir, pd);
 355         }
 356         if (pd->lookup.done > 0) {
 357                 hdr.uid = pd->lookup.uid;
 358                 hdr.pid = pd->lookup.pid;
 359         } else {
 360                 hdr.uid = UID_MAX;
 361                 hdr.pid = NO_PID;
 362         }
 363         hdr.rule_uid = rm->cuid;
 364         hdr.rule_pid = rm->cpid;
 365         hdr.dir = dir;
 366
 367 #if INET
 368         if (af == AF_INET && dir == PF_OUT) {
 369                 struct ip *ip;
 370
 371                 ip = mtod(m, struct ip *);
 372                 ip->ip_sum = 0;
 373                 ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
 374         }
 375 #endif /* INET */
 376
 377         atomic_add_64(&ifn->if_opackets, 1);
 378         atomic_add_64(&ifn->if_obytes, m->m_pkthdr.len);
 379
 380         switch (dir) {
 381         case PF_IN:
 382                 bpf_tap_in(ifn, DLT_PFLOG, m, &hdr, PFLOG_HDRLEN);
 383                 break;
 384
 385         case PF_OUT:
 386                 bpf_tap_out(ifn, DLT_PFLOG, m, &hdr, PFLOG_HDRLEN);
 387                 break;
 388
 389         default:
 390                 break;
 391         }
 392 #endif /* NBPFILTER > 0 */
 393         return 0;
 394 }