1 /* $OpenBSD: if_pflog.c,v 1.27 2007/12/20 02:53:02 brad Exp $ */ 2 /* 3 * The authors of this code are John Ioannidis (ji@tla.org), 4 * Angelos D. Keromytis (kermit@csd.uch.gr) and 5 * Niels Provos (provos@physnet.uni-hamburg.de). 6 * 7 * This code was written by John Ioannidis for BSD/OS in Athens, Greece, 8 * in November 1995. 9 * 10 * Ported to OpenBSD and NetBSD, with additional transforms, in December 1996, 11 * by Angelos D. Keromytis. 12 * 13 * Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis 14 * and Niels Provos. 15 * 16 * Copyright (C) 1995, 1996, 1997, 1998 by John Ioannidis, Angelos D. Keromytis 17 * and Niels Provos. 18 * Copyright (c) 2001, Angelos D. Keromytis, Niels Provos. 19 * 20 * Permission to use, copy, and modify this software with or without fee 21 * is hereby granted, provided that this entire notice is included in 22 * all copies of any software which is or includes a copy or 23 * modification of this software. 24 * You may use this code under the GNU public license if you so wish. Please 25 * contribute changes back to the authors under this freer than GPL license 26 * so that we may further the use of strong encryption without limitations to 27 * all. 28 * 29 * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR 30 * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY 31 * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE 32 * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR 33 * PURPOSE. 34 */ 35 36 #include "bpfilter.h" 37 #include "pflog.h" 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/mbuf.h> 42 #include <sys/proc.h> 43 #include <sys/socket.h> 44 #include <sys/ioctl.h> 45 46 #include <net/if.h> 47 #include <net/if_types.h> 48 #include <net/route.h> 49 #include <net/bpf.h> 50 51 #ifdef INET 52 #include <netinet/in.h> 53 #include <netinet/in_var.h> 54 #include <netinet/in_systm.h> 55 #include <netinet/ip.h> 56 #endif 57 58 #ifdef INET6 59 #ifndef INET 60 #include <netinet/in.h> 61 #endif 62 #include <netinet6/nd6.h> 63 #endif /* INET6 */ 64 65 #include <net/pfvar.h> 66 #include <net/if_pflog.h> 67 68 #define PFLOGMTU (32768 + MHLEN + MLEN) 69 70 #ifdef PFLOGDEBUG 71 #define DPRINTF(x) do { if (pflogdebug) printf x ; } while (0) 72 #else 73 #define DPRINTF(x) 74 #endif 75 76 void pflogattach(int); 77 int pflogoutput(struct ifnet *, struct mbuf *, struct sockaddr *, 78 struct rtentry *); 79 int pflogioctl(struct ifnet *, u_long, caddr_t); 80 void pflogstart(struct ifnet *); 81 int pflog_clone_create(struct if_clone *, int); 82 int pflog_clone_destroy(struct ifnet *); 83 84 LIST_HEAD(, pflog_softc) pflogif_list; 85 struct if_clone pflog_cloner = 86 IF_CLONE_INITIALIZER("pflog", pflog_clone_create, pflog_clone_destroy); 87 88 struct ifnet *pflogifs[PFLOGIFS_MAX]; /* for fast access */ 89 90 void 91 pflogattach(int npflog) 92 { 93 int i; 94 LIST_INIT(&pflogif_list); 95 for (i = 0; i < PFLOGIFS_MAX; i++) 96 pflogifs[i] = NULL; 97 if_clone_attach(&pflog_cloner); 98 } 99 100 int 101 pflog_clone_create(struct if_clone *ifc, int unit) 102 { 103 struct ifnet *ifp; 104 struct pflog_softc *pflogif; 105 int s; 106 107 if (unit >= PFLOGIFS_MAX) 108 return (EINVAL); 109 110 if ((pflogif = malloc(sizeof(*pflogif), 111 M_DEVBUF, M_NOWAIT|M_ZERO)) == NULL) 112 return (ENOMEM); 113 114 pflogif->sc_unit = unit; 115 ifp = &pflogif->sc_if; 116 snprintf(ifp->if_xname, sizeof ifp->if_xname, "pflog%d", unit); 117 ifp->if_softc = pflogif; 118 ifp->if_mtu = PFLOGMTU; 119 ifp->if_ioctl = pflogioctl; 120 ifp->if_output = pflogoutput; 121 ifp->if_start = pflogstart; 122 ifp->if_type = IFT_PFLOG; 123 ifp->if_snd.ifq_maxlen = ifqmaxlen; 124 ifp->if_hdrlen = PFLOG_HDRLEN; 125 if_attach(ifp); 126 if_alloc_sadl(ifp); 127 128 #if NBPFILTER > 0 129 bpfattach(&pflogif->sc_if.if_bpf, ifp, DLT_PFLOG, PFLOG_HDRLEN); 130 #endif 131 132 s = splnet(); 133 LIST_INSERT_HEAD(&pflogif_list, pflogif, sc_list); 134 pflogifs[unit] = ifp; 135 splx(s); 136 137 return (0); 138 } 139 140 int 141 pflog_clone_destroy(struct ifnet *ifp) 142 { 143 struct pflog_softc *pflogif = ifp->if_softc; 144 int s; 145 146 s = splnet(); 147 pflogifs[pflogif->sc_unit] = NULL; 148 LIST_REMOVE(pflogif, sc_list); 149 splx(s); 150 151 #if NBPFILTER > 0 152 bpfdetach(ifp); 153 #endif 154 if_detach(ifp); 155 free(pflogif, M_DEVBUF); 156 return (0); 157 } 158 159 /* 160 * Start output on the pflog interface. 161 */ 162 void 163 pflogstart(struct ifnet *ifp) 164 { 165 struct mbuf *m; 166 int s; 167 168 for (;;) { 169 s = splnet(); 170 IF_DROP(&ifp->if_snd); 171 IF_DEQUEUE(&ifp->if_snd, m); 172 splx(s); 173 174 if (m == NULL) 175 return; 176 else 177 m_freem(m); 178 } 179 } 180 181 int 182 pflogoutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, 183 struct rtentry *rt) 184 { 185 m_freem(m); 186 return (0); 187 } 188 189 /* ARGSUSED */ 190 int 191 pflogioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 192 { 193 switch (cmd) { 194 case SIOCSIFFLAGS: 195 if (ifp->if_flags & IFF_UP) 196 ifp->if_flags |= IFF_RUNNING; 197 else 198 ifp->if_flags &= ~IFF_RUNNING; 199 break; 200 default: 201 return (ENOTTY); 202 } 203 204 return (0); 205 } 206 207 int 208 pflog_packet(struct pfi_kif *kif, struct mbuf *m, sa_family_t af, u_int8_t dir, 209 u_int8_t reason, struct pf_rule *rm, struct pf_rule *am, 210 struct pf_ruleset *ruleset, struct pf_pdesc *pd) 211 { 212 #if NBPFILTER > 0 213 struct ifnet *ifn; 214 struct pfloghdr hdr; 215 216 if (kif == NULL || m == NULL || rm == NULL || pd == NULL) 217 return (-1); 218 219 if ((ifn = pflogifs[rm->logif]) == NULL || !ifn->if_bpf) 220 return (0); 221 222 bzero(&hdr, sizeof(hdr)); 223 hdr.length = PFLOG_REAL_HDRLEN; 224 hdr.af = af; 225 hdr.action = rm->action; 226 hdr.reason = reason; 227 memcpy(hdr.ifname, kif->pfik_name, sizeof(hdr.ifname)); 228 229 if (am == NULL) { 230 hdr.rulenr = htonl(rm->nr); 231 hdr.subrulenr = -1; 232 } else { 233 hdr.rulenr = htonl(am->nr); 234 hdr.subrulenr = htonl(rm->nr); 235 if (ruleset != NULL && ruleset->anchor != NULL) 236 strlcpy(hdr.ruleset, ruleset->anchor->name, 237 sizeof(hdr.ruleset)); 238 } 239 if (rm->log & PF_LOG_SOCKET_LOOKUP && !pd->lookup.done) 240 pd->lookup.done = pf_socket_lookup(dir, pd); 241 if (pd->lookup.done > 0) { 242 hdr.uid = pd->lookup.uid; 243 hdr.pid = pd->lookup.pid; 244 } else { 245 hdr.uid = UID_MAX; 246 hdr.pid = NO_PID; 247 } 248 hdr.rule_uid = rm->cuid; 249 hdr.rule_pid = rm->cpid; 250 hdr.dir = dir; 251 252 #ifdef INET 253 if (af == AF_INET && dir == PF_OUT) { 254 struct ip *ip; 255 256 ip = mtod(m, struct ip *); 257 ip->ip_sum = 0; 258 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 259 } 260 #endif /* INET */ 261 262 ifn->if_opackets++; 263 ifn->if_obytes += m->m_pkthdr.len; 264 bpf_mtap_hdr(ifn->if_bpf, (char *)&hdr, PFLOG_HDRLEN, m, 265 BPF_DIRECTION_OUT); 266 #endif 267 268 return (0); 269 } 270