bsd/net/if_pflog.c

   1 /*
   2  * Copyright (c) 2007-2010 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 <net/if.h>
  74 #include <net/if_var.h>
  75 #include <net/if_types.h>
  76 #include <net/route.h>
  77 #include <net/bpf.h>
  78
  79 #if INET
  80 #include <netinet/in.h>
  81 #include <netinet/in_var.h>
  82 #include <netinet/in_systm.h>
  83 #include <netinet/ip.h>
  84 #endif
  85
  86 #if INET6
  87 #if !INET
  88 #include <netinet/in.h>
  89 #endif
  90 #include <netinet6/nd6.h>
  91 #endif /* INET6 */
  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_clone_create(struct if_clone *, u_int32_t, void *);
 106 static int pflog_clone_destroy(struct ifnet *);
 107 static errno_t pflogoutput(struct ifnet *, struct mbuf *);
 108 static errno_t pflogioctl(struct ifnet *, unsigned long, void *);
 109 static errno_t pflogdemux(struct ifnet *, struct mbuf *, char *,
 110     protocol_family_t *);
 111 static errno_t pflogaddproto(struct ifnet *, protocol_family_t,
 112     const struct ifnet_demux_desc *, u_int32_t);
 113 static errno_t pflogdelproto(struct ifnet *, protocol_family_t);
 114 static void pflogfree(struct ifnet *);
 115
 116 static LIST_HEAD(, pflog_softc) pflogif_list;
 117 static struct if_clone pflog_cloner =
 118     IF_CLONE_INITIALIZER(PFLOGNAME, pflog_clone_create, pflog_clone_destroy,
 119         0, (PFLOGIFS_MAX - 1));
 120
 121 struct ifnet *pflogifs[PFLOGIFS_MAX];   /* for fast access */
 122
 123 void
 124 pfloginit(void)
 125 {
 126         int i;
 127
 128         LIST_INIT(&pflogif_list);
 129         for (i = 0; i < PFLOGIFS_MAX; i++)
 130                 pflogifs[i] = NULL;
 131
 132         (void) if_clone_attach(&pflog_cloner);
 133 }
 134
 135 static int
 136 pflog_clone_create(struct if_clone *ifc, u_int32_t unit, __unused void *params)
 137 {
 138         struct pflog_softc *pflogif;
 139         struct ifnet_init_params pf_init;
 140         int error = 0;
 141
 142         if (unit >= PFLOGIFS_MAX) {
 143                 /* Either the interface cloner or our initializer is broken */
 144                 panic("%s: unit (%d) exceeds max (%d)", __func__, unit,
 145                     PFLOGIFS_MAX);
 146                 /* NOTREACHED */
 147         }
 148
 149         if ((pflogif = _MALLOC(sizeof (*pflogif),
 150             M_DEVBUF, M_WAITOK|M_ZERO)) == NULL) {
 151                 error = ENOMEM;
 152                 goto done;
 153         }
 154
 155         bzero(&pf_init, sizeof (pf_init));
 156         pf_init.name = ifc->ifc_name;
 157         pf_init.unit = unit;
 158         pf_init.type = IFT_PFLOG;
 159         pf_init.family = IFNET_FAMILY_LOOPBACK;
 160         pf_init.output = pflogoutput;
 161         pf_init.demux = pflogdemux;
 162         pf_init.add_proto = pflogaddproto;
 163         pf_init.del_proto = pflogdelproto;
 164         pf_init.softc = pflogif;
 165         pf_init.ioctl = pflogioctl;
 166         pf_init.detach = pflogfree;
 167
 168         bzero(pflogif, sizeof (*pflogif));
 169         pflogif->sc_unit = unit;
 170
 171         error = ifnet_allocate(&pf_init, &pflogif->sc_if);
 172         if (error != 0) {
 173                 printf("%s: ifnet_allocate failed - %d\n", __func__, error);
 174                 _FREE(pflogif, M_DEVBUF);
 175                 goto done;
 176         }
 177
 178         ifnet_set_mtu(pflogif->sc_if, PFLOGMTU);
 179         ifnet_set_flags(pflogif->sc_if, IFF_UP, IFF_UP);
 180
 181         error = ifnet_attach(pflogif->sc_if, NULL);
 182         if (error != 0) {
 183                 printf("%s: ifnet_attach failed - %d\n", __func__, error);
 184                 ifnet_release(pflogif->sc_if);
 185                 _FREE(pflogif, M_DEVBUF);
 186                 goto done;
 187         }
 188
 189 #if NBPFILTER > 0
 190         bpfattach(pflogif->sc_if, DLT_PFLOG, PFLOG_HDRLEN);
 191 #endif
 192
 193         lck_rw_lock_shared(pf_perim_lock);
 194         lck_mtx_lock(pf_lock);
 195         LIST_INSERT_HEAD(&pflogif_list, pflogif, sc_list);
 196         pflogifs[unit] = pflogif->sc_if;
 197         lck_mtx_unlock(pf_lock);
 198         lck_rw_done(pf_perim_lock);
 199
 200 done:
 201         return (error);
 202 }
 203
 204 static int
 205 pflog_clone_destroy(struct ifnet *ifp)
 206 {
 207         struct pflog_softc *pflogif = ifp->if_softc;
 208
 209         lck_rw_lock_shared(pf_perim_lock);
 210         lck_mtx_lock(pf_lock);
 211         pflogifs[pflogif->sc_unit] = NULL;
 212         LIST_REMOVE(pflogif, sc_list);
 213         lck_mtx_unlock(pf_lock);
 214         lck_rw_done(pf_perim_lock);
 215
 216         /* bpfdetach() is taken care of as part of interface detach */
 217         (void) ifnet_detach(ifp);
 218
 219         return 0;
 220 }
 221
 222 static errno_t
 223 pflogoutput(struct ifnet *ifp, struct mbuf *m)
 224 {
 225         printf("%s: freeing data for %s%d\n", __func__, ifp->if_name,
 226             ifp->if_unit);
 227         m_freem(m);
 228         return (ENOTSUP);
 229 }
 230
 231 static errno_t
 232 pflogioctl(struct ifnet *ifp, unsigned long cmd, void *data)
 233 {
 234 #pragma unused(data)
 235         switch (cmd) {
 236         case SIOCSIFADDR:
 237         case SIOCAIFADDR:
 238         case SIOCSIFDSTADDR:
 239         case SIOCSIFFLAGS:
 240                 if (ifnet_flags(ifp) & IFF_UP)
 241                         ifnet_set_flags(ifp, IFF_RUNNING, IFF_RUNNING);
 242                 else
 243                         ifnet_set_flags(ifp, 0, IFF_RUNNING);
 244                 break;
 245         default:
 246                 return (ENOTTY);
 247         }
 248
 249         return (0);
 250 }
 251
 252 static errno_t
 253 pflogdemux(struct ifnet *ifp, struct mbuf *m, char *h, protocol_family_t *ppf)
 254 {
 255 #pragma unused(h, ppf)
 256         printf("%s: freeing data for %s%d\n", __func__, ifp->if_name,
 257             ifp->if_unit);
 258         m_freem(m);
 259         return (EJUSTRETURN);
 260 }
 261
 262 static errno_t
 263 pflogaddproto(struct ifnet *ifp, protocol_family_t pf,
 264     const struct ifnet_demux_desc *d, u_int32_t cnt)
 265 {
 266 #pragma unused(ifp, pf, d, cnt)
 267         return (0);
 268 }
 269
 270 static errno_t
 271 pflogdelproto(struct ifnet *ifp, protocol_family_t pf)
 272 {
 273 #pragma unused(ifp, pf)
 274         return (0);
 275 }
 276
 277 static void
 278 pflogfree(struct ifnet *ifp)
 279 {
 280         _FREE(ifp->if_softc, M_DEVBUF);
 281         ifp->if_softc = NULL;
 282         (void) ifnet_release(ifp);
 283 }
 284
 285 int
 286 pflog_packet(struct pfi_kif *kif, struct mbuf *m, sa_family_t af, u_int8_t dir,
 287     u_int8_t reason, struct pf_rule *rm, struct pf_rule *am,
 288     struct pf_ruleset *ruleset, struct pf_pdesc *pd)
 289 {
 290 #if NBPFILTER > 0
 291         struct ifnet *ifn;
 292         struct pfloghdr hdr;
 293
 294         lck_mtx_assert(pf_lock, LCK_MTX_ASSERT_OWNED);
 295
 296         if (kif == NULL || m == NULL || rm == NULL || pd == NULL)
 297                 return (-1);
 298
 299         if (rm->logif >= PFLOGIFS_MAX ||
 300             (ifn = pflogifs[rm->logif]) == NULL || !ifn->if_bpf) {
 301                 return (0);
 302         }
 303
 304         bzero(&hdr, sizeof (hdr));
 305         hdr.length = PFLOG_REAL_HDRLEN;
 306         hdr.af = af;
 307         hdr.action = rm->action;
 308         hdr.reason = reason;
 309         memcpy(hdr.ifname, kif->pfik_name, sizeof (hdr.ifname));
 310
 311         if (am == NULL) {
 312                 hdr.rulenr = htonl(rm->nr);
 313                 hdr.subrulenr = -1;
 314         } else {
 315                 hdr.rulenr = htonl(am->nr);
 316                 hdr.subrulenr = htonl(rm->nr);
 317                 if (ruleset != NULL && ruleset->anchor != NULL)
 318                         strlcpy(hdr.ruleset, ruleset->anchor->name,
 319                             sizeof (hdr.ruleset));
 320         }
 321         if (rm->log & PF_LOG_SOCKET_LOOKUP && !pd->lookup.done)
 322                 pd->lookup.done = pf_socket_lookup(dir, pd);
 323         if (pd->lookup.done > 0) {
 324                 hdr.uid = pd->lookup.uid;
 325                 hdr.pid = pd->lookup.pid;
 326         } else {
 327                 hdr.uid = UID_MAX;
 328                 hdr.pid = NO_PID;
 329         }
 330         hdr.rule_uid = rm->cuid;
 331         hdr.rule_pid = rm->cpid;
 332         hdr.dir = dir;
 333
 334 #if INET
 335         if (af == AF_INET && dir == PF_OUT) {
 336                 struct ip *ip;
 337
 338                 ip = mtod(m, struct ip *);
 339                 ip->ip_sum = 0;
 340                 ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
 341         }
 342 #endif /* INET */
 343
 344         atomic_add_64(&ifn->if_opackets, 1);
 345         atomic_add_64(&ifn->if_obytes, m->m_pkthdr.len);
 346
 347         switch (dir) {
 348         case PF_IN:
 349                 bpf_tap_in(ifn, DLT_PFLOG, m, &hdr, PFLOG_HDRLEN);
 350                 break;
 351
 352         case PF_OUT:
 353                 bpf_tap_out(ifn, DLT_PFLOG, m, &hdr, PFLOG_HDRLEN);
 354                 break;
 355
 356         default:
 357                 break;
 358         }
 359 #endif /* NBPFILTER > 0 */
 360         return (0);
 361 }