Home | History | Annotate | Line # | Download | only in net
if_pflog.c revision 1.11.12.2 
      1 /*	$NetBSD: if_pflog.c,v 1.11.12.2 2009/08/19 18:47:33 yamt Exp $	*/
      2 /*	$OpenBSD: if_pflog.c,v 1.24 2007/05/26 17:13:30 jason Exp $	*/
      3 
      4 /*
      5  * The authors of this code are John Ioannidis (ji (at) tla.org),
      6  * Angelos D. Keromytis (kermit (at) csd.uch.gr) and
      7  * Niels Provos (provos (at) physnet.uni-hamburg.de).
      8  *
      9  * This code was written by John Ioannidis for BSD/OS in Athens, Greece,
     10  * in November 1995.
     11  *
     12  * Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
     13  * by Angelos D. Keromytis.
     14  *
     15  * Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis
     16  * and Niels Provos.
     17  *
     18  * Copyright (C) 1995, 1996, 1997, 1998 by John Ioannidis, Angelos D. Keromytis
     19  * and Niels Provos.
     20  * Copyright (c) 2001, Angelos D. Keromytis, Niels Provos.
     21  *
     22  * Permission to use, copy, and modify this software with or without fee
     23  * is hereby granted, provided that this entire notice is included in
     24  * all copies of any software which is or includes a copy or
     25  * modification of this software.
     26  * You may use this code under the GNU public license if you so wish. Please
     27  * contribute changes back to the authors under this freer than GPL license
     28  * so that we may further the use of strong encryption without limitations to
     29  * all.
     30  *
     31  * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
     32  * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
     33  * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
     34  * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
     35  * PURPOSE.
     36  */
     37 
     38 #include <sys/cdefs.h>
     39 __KERNEL_RCSID(0, "$NetBSD: if_pflog.c,v 1.11.12.2 2009/08/19 18:47:33 yamt Exp $");
     40 
     41 #ifdef _KERNEL_OPT
     42 #include "opt_inet.h"
     43 #endif
     44 
     45 #include "bpfilter.h"
     46 #include "pflog.h"
     47 
     48 #include <sys/param.h>
     49 #include <sys/systm.h>
     50 #include <sys/mbuf.h>
     51 #include <sys/proc.h>
     52 #include <sys/socket.h>
     53 #include <sys/ioctl.h>
     54 
     55 #include <net/if.h>
     56 #include <net/if_types.h>
     57 #include <net/route.h>
     58 #include <net/bpf.h>
     59 
     60 #ifdef	INET
     61 #include <netinet/in.h>
     62 #include <netinet/in_var.h>
     63 #include <netinet/in_systm.h>
     64 #include <netinet/ip.h>
     65 #endif
     66 
     67 #ifdef INET6
     68 #ifndef INET
     69 #include <netinet/in.h>
     70 #endif
     71 #include <netinet6/nd6.h>
     72 #endif /* INET6 */
     73 
     74 #include <net/pfvar.h>
     75 #include <net/if_pflog.h>
     76 
     77 #define PFLOGMTU	(32768 + MHLEN + MLEN)
     78 
     79 #ifdef PFLOGDEBUG
     80 #define DPRINTF(x)    do { if (pflogdebug) printf x ; } while (0)
     81 #else
     82 #define DPRINTF(x)
     83 #endif
     84 
     85 void	pflogattach(int);
     86 int	pflogoutput(struct ifnet *, struct mbuf *, const struct sockaddr *,
     87 	    	       struct rtentry *);
     88 int	pflogioctl(struct ifnet *, u_long, void *);
     89 void	pflogstart(struct ifnet *);
     90 int	pflog_clone_create(struct if_clone *, int);
     91 int	pflog_clone_destroy(struct ifnet *);
     92 
     93 LIST_HEAD(, pflog_softc)	pflogif_list;
     94 struct if_clone	pflog_cloner =
     95     IF_CLONE_INITIALIZER("pflog", pflog_clone_create, pflog_clone_destroy);
     96 
     97 struct ifnet	*pflogifs[PFLOGIFS_MAX];	/* for fast access */
     98 
     99 void
    100 pflogattach(int npflog)
    101 {
    102 	int i;
    103 
    104 	LIST_INIT(&pflogif_list);
    105 	for (i = 0; i < PFLOGIFS_MAX; i++)
    106 		pflogifs[i] = NULL;
    107 	if_clone_attach(&pflog_cloner);
    108 }
    109 
    110 int
    111 pflog_clone_create(struct if_clone *ifc, int unit)
    112 {
    113 	struct ifnet *ifp;
    114 	struct pflog_softc *pflogif;
    115 	int s;
    116 
    117 	if (unit >= PFLOGIFS_MAX)
    118 		return (EINVAL);
    119 
    120 	if ((pflogif = malloc(sizeof(*pflogif), M_DEVBUF, M_NOWAIT|M_ZERO)) == NULL)
    121 		return (ENOMEM);
    122 
    123 	pflogif->sc_unit = unit;
    124 	ifp = &pflogif->sc_if;
    125 	snprintf(ifp->if_xname, sizeof ifp->if_xname, "pflog%d", unit);
    126 	ifp->if_softc = pflogif;
    127 	ifp->if_mtu = PFLOGMTU;
    128 	ifp->if_ioctl = pflogioctl;
    129 	ifp->if_output = pflogoutput;
    130 	ifp->if_start = pflogstart;
    131 	ifp->if_type = IFT_PFLOG;
    132 #ifndef __NetBSD__
    133 	ifp->if_snd.ifq_maxlen = ifqmaxlen;
    134 #endif /* !__NetBSD__ */
    135 	ifp->if_hdrlen = PFLOG_HDRLEN;
    136 	if_attach(ifp);
    137 	if_alloc_sadl(ifp);
    138 
    139 #if NBPFILTER > 0
    140 #ifdef __NetBSD__
    141 	bpfattach(ifp, DLT_PFLOG, PFLOG_HDRLEN);
    142 #else
    143 	bpfattach(&pflogif->sc_if.if_bpf, ifp, DLT_PFLOG, PFLOG_HDRLEN);
    144 #endif /* !__NetBSD__ */
    145 #endif
    146 
    147 	s = splnet();
    148 	LIST_INSERT_HEAD(&pflogif_list, pflogif, sc_list);
    149 	pflogifs[unit] = ifp;
    150 	splx(s);
    151 
    152 	return (0);
    153 }
    154 
    155 int
    156 pflog_clone_destroy(struct ifnet *ifp)
    157 {
    158 	struct pflog_softc	*pflogif = ifp->if_softc;
    159 	int			 s;
    160 
    161 	s = splnet();
    162 	pflogifs[pflogif->sc_unit] = NULL;
    163 	LIST_REMOVE(pflogif, sc_list);
    164 	splx(s);
    165 
    166 #if NBPFILTER > 0
    167 	bpfdetach(ifp);
    168 #endif
    169 	if_detach(ifp);
    170 	free(pflogif, M_DEVBUF);
    171 	return (0);
    172 }
    173 
    174 /*
    175  * Start output on the pflog interface.
    176  */
    177 void
    178 pflogstart(struct ifnet *ifp)
    179 {
    180 	struct mbuf *m;
    181 	int s;
    182 
    183 	for (;;) {
    184 		s = splnet();
    185 		IF_DROP(&ifp->if_snd);
    186 		IF_DEQUEUE(&ifp->if_snd, m);
    187 		splx(s);
    188 
    189 		if (m == NULL)
    190 			return;
    191 		else
    192 			m_freem(m);
    193 	}
    194 }
    195 
    196 int
    197 pflogoutput(struct ifnet *ifp, struct mbuf *m,
    198     const struct sockaddr *dst, struct rtentry *rt)
    199 {
    200 	m_freem(m);
    201 	return (0);
    202 }
    203 
    204 /* ARGSUSED */
    205 int
    206 pflogioctl(struct ifnet *ifp, u_long cmd, void *data)
    207 {
    208 	int error = 0;
    209 
    210 	switch (cmd) {
    211 	case SIOCSIFFLAGS:
    212 		if ((error = ifioctl_common(ifp, cmd, data)) != 0)
    213 			break;
    214 		/*FALLTHROUGH*/
    215 	case SIOCINITIFADDR:
    216 	case SIOCAIFADDR:
    217 	case SIOCSIFDSTADDR:
    218 		if (ifp->if_flags & IFF_UP)
    219 			ifp->if_flags |= IFF_RUNNING;
    220 		else
    221 			ifp->if_flags &= ~IFF_RUNNING;
    222 		break;
    223 	default:
    224 		error = ifioctl_common(ifp, cmd, data);
    225 	}
    226 
    227 	return error;
    228 }
    229 
    230 int
    231 pflog_packet(struct pfi_kif *kif, struct mbuf *m, sa_family_t af, u_int8_t dir,
    232     u_int8_t reason, struct pf_rule *rm, struct pf_rule *am,
    233     struct pf_ruleset *ruleset, struct pf_pdesc *pd)
    234 {
    235 #if NBPFILTER > 0
    236 	struct ifnet *ifn;
    237 	struct pfloghdr hdr;
    238 
    239 	if (kif == NULL || m == NULL || rm == NULL || pd == NULL)
    240 		return (-1);
    241 
    242 	if ((ifn = pflogifs[rm->logif]) == NULL || !ifn->if_bpf)
    243 		return (0);
    244 
    245 	bzero(&hdr, sizeof(hdr));
    246 	hdr.length = PFLOG_REAL_HDRLEN;
    247 	hdr.af = af;
    248 	hdr.action = rm->action;
    249 	hdr.reason = reason;
    250 	memcpy(hdr.ifname, kif->pfik_name, sizeof(hdr.ifname));
    251 
    252 	if (am == NULL) {
    253 		hdr.rulenr = htonl(rm->nr);
    254 		hdr.subrulenr = -1;
    255 	} else {
    256 		hdr.rulenr = htonl(am->nr);
    257 		hdr.subrulenr = htonl(rm->nr);
    258 		if (ruleset != NULL && ruleset->anchor != NULL)
    259 			strlcpy(hdr.ruleset, ruleset->anchor->name,
    260 			    sizeof(hdr.ruleset));
    261 	}
    262 	if (rm->log & PF_LOG_SOCKET_LOOKUP && !pd->lookup.done)
    263 		pd->lookup.done = pf_socket_lookup(dir, pd);
    264 	if (pd->lookup.done > 0) {
    265 		hdr.uid = pd->lookup.uid;
    266 		hdr.pid = pd->lookup.pid;
    267 	} else {
    268 		hdr.uid = UID_MAX;
    269 		hdr.pid = NO_PID;
    270 	}
    271 	hdr.rule_uid = rm->cuid;
    272 	hdr.rule_pid = rm->cpid;
    273 	hdr.dir = dir;
    274 
    275 #ifdef INET
    276 	if (af == AF_INET && dir == PF_OUT) {
    277 		struct ip *ip;
    278 
    279 		ip = mtod(m, struct ip *);
    280 		ip->ip_sum = 0;
    281 		ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
    282 	}
    283 #endif /* INET */
    284 
    285 	ifn->if_opackets++;
    286 	ifn->if_obytes += m->m_pkthdr.len;
    287 
    288 #ifdef __NetBSD__
    289 	bpf_mtap2(ifn->if_bpf, &hdr, PFLOG_HDRLEN, m);
    290 #else
    291 	bpf_mtap_hdr(ifn->if_bpf, (char *)&hdr, PFLOG_HDRLEN, m,
    292 	    BPF_DIRECTION_OUT);
    293 #endif /* !__NetBSD__ */
    294 
    295 #endif
    296 
    297 	return (0);
    298 }
    299