1 /* $OpenBSD: if_pflog.c,v 1.24 2007/05/26 17:13:30 jason 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 * Copyright (c) 2004 The DragonFly Project. All rights reserved. 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 "opt_inet.h" 39 #include "opt_inet6.h" 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/in_cksum.h> 44 #include <sys/mbuf.h> 45 #include <sys/proc.h> 46 #include <sys/socket.h> 47 #include <sys/kernel.h> 48 #include <sys/malloc.h> 49 #include <sys/module.h> 50 #include <sys/sockio.h> 51 #include <sys/thread2.h> 52 #include <vm/vm_zone.h> 53 54 #include <net/if.h> 55 #include <net/if_types.h> 56 #include <net/route.h> 57 #include <net/bpf.h> 58 59 #ifdef INET 60 #include <netinet/in.h> 61 #include <netinet/in_var.h> 62 #include <netinet/in_systm.h> 63 #include <netinet/ip.h> 64 #endif 65 66 #ifdef INET6 67 #ifndef INET 68 #include <netinet/in.h> 69 #endif 70 #include <netinet6/nd6.h> 71 #endif /* INET6 */ 72 73 #include <net/pf/pfvar.h> 74 #include <net/pf/if_pflog.h> 75 76 #define PFLOGNAME "pflog" 77 78 #define PFLOGMTU (32768 + MHLEN + MLEN) 79 80 #ifdef PFLOGDEBUG 81 #define DPRINTF(x) do { if (pflogdebug) kprintf x ; } while (0) 82 #else 83 #define DPRINTF(x) 84 #endif 85 86 void pflogattach(int); 87 int pflogoutput(struct ifnet *, struct mbuf *, struct sockaddr *, 88 struct rtentry *); 89 int pflogioctl(struct ifnet *, u_long, caddr_t, struct ucred *); 90 void pflogrtrequest(int, struct rtentry *, struct sockaddr *); 91 void pflogstart(struct ifnet *); 92 int pflog_clone_create(struct if_clone *, int, caddr_t); 93 void pflog_clone_destroy(struct ifnet *); 94 95 LIST_HEAD(, pflog_softc) pflogif_list; 96 struct if_clone pflog_cloner = 97 IF_CLONE_INITIALIZER("pflog", pflog_clone_create, pflog_clone_destroy, 1, 1); 98 99 struct ifnet *pflogifs[PFLOGIFS_MAX]; /* for fast access */ 100 101 void 102 pflogattach(int npflog) 103 { 104 int i; 105 LIST_INIT(&pflogif_list); 106 for (i = 0; i < PFLOGIFS_MAX; i++) 107 pflogifs[i] = NULL; 108 if_clone_attach(&pflog_cloner); 109 } 110 111 int 112 pflog_clone_create(struct if_clone *ifc, int unit, caddr_t param __unused) 113 { 114 struct ifnet *ifp; 115 struct pflog_softc *pflogif; 116 117 if (unit >= PFLOGIFS_MAX) 118 return (EINVAL); 119 120 if ((pflogif = kmalloc(sizeof(*pflogif), M_DEVBUF, M_WAITOK)) == NULL) 121 return (ENOMEM); 122 bzero(pflogif, sizeof(*pflogif)); 123 124 pflogif->sc_unit = unit; 125 ifp = &pflogif->sc_if; 126 ksnprintf(ifp->if_xname, sizeof ifp->if_xname, "pflog%d", unit); 127 ifp->if_softc = pflogif; 128 ifp->if_mtu = PFLOGMTU; 129 ifp->if_ioctl = pflogioctl; 130 ifp->if_output = pflogoutput; 131 ifp->if_start = pflogstart; 132 ifp->if_type = IFT_PFLOG; 133 ifp->if_snd.ifq_maxlen = ifqmaxlen; 134 ifp->if_hdrlen = PFLOG_HDRLEN; 135 if_attach(ifp, NULL); 136 137 bpfattach(&pflogif->sc_if, DLT_PFLOG, PFLOG_HDRLEN); 138 139 crit_enter(); 140 LIST_INSERT_HEAD(&pflogif_list, pflogif, sc_list); 141 pflogifs[unit] = ifp; 142 crit_exit(); 143 144 return (0); 145 } 146 147 void 148 pflog_clone_destroy(struct ifnet *ifp) 149 { 150 struct pflog_softc *pflogif = ifp->if_softc; 151 152 crit_enter(); 153 pflogifs[pflogif->sc_unit] = NULL; 154 LIST_REMOVE(pflogif, sc_list); 155 crit_exit(); 156 157 #if NBPFILTER > 0 158 bpfdetach(ifp); 159 #endif 160 if_detach(ifp); 161 kfree(pflogif, M_DEVBUF); 162 } 163 164 /* 165 * Start output on the pflog interface. 166 */ 167 void 168 pflogstart(struct ifnet *ifp) 169 { 170 struct mbuf *m; 171 172 for (;;) { 173 crit_enter(); 174 IF_DROP(&ifp->if_snd); 175 IF_DEQUEUE(&ifp->if_snd, m); 176 crit_exit(); 177 178 if (m == NULL) 179 return; 180 else 181 m_freem(m); 182 } 183 } 184 185 int 186 pflogoutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, 187 struct rtentry *rt) 188 { 189 m_freem(m); 190 return (0); 191 } 192 193 /* ARGSUSED */ 194 void 195 pflogrtrequest(int cmd, struct rtentry *rt, struct sockaddr *sa) 196 { 197 if (rt) 198 rt->rt_rmx.rmx_mtu = PFLOGMTU; 199 } 200 201 /* ARGSUSED */ 202 int 203 pflogioctl(struct ifnet *ifp, u_long cmd, caddr_t data, struct ucred *cr) 204 { 205 switch (cmd) { 206 case SIOCSIFADDR: 207 case SIOCAIFADDR: 208 case SIOCSIFDSTADDR: 209 case SIOCSIFFLAGS: 210 if (ifp->if_flags & IFF_UP) 211 ifp->if_flags |= IFF_RUNNING; 212 else 213 ifp->if_flags &= ~IFF_RUNNING; 214 break; 215 default: 216 return (EINVAL); 217 } 218 219 return (0); 220 } 221 222 int 223 pflog_packet(struct pfi_kif *kif, struct mbuf *m, sa_family_t af, u_int8_t dir, 224 u_int8_t reason, struct pf_rule *rm, struct pf_rule *am, 225 struct pf_ruleset *ruleset, struct pf_pdesc *pd) 226 { 227 struct ifnet *ifn = NULL; 228 struct pfloghdr hdr; 229 230 if (kif == NULL || m == NULL || rm == NULL) 231 return (-1); 232 233 if ((ifn = pflogifs[rm->logif]) == NULL || !ifn->if_bpf) 234 return (0); 235 236 bzero(&hdr, sizeof(hdr)); 237 hdr.length = PFLOG_REAL_HDRLEN; 238 hdr.af = af; 239 hdr.action = rm->action; 240 hdr.reason = reason; 241 memcpy(hdr.ifname, kif->pfik_name, sizeof(hdr.ifname)); 242 243 if (am == NULL) { 244 hdr.rulenr = htonl(rm->nr); 245 hdr.subrulenr = -1; 246 } else { 247 hdr.rulenr = htonl(am->nr); 248 hdr.subrulenr = htonl(rm->nr); 249 if (ruleset != NULL && ruleset->anchor != NULL) 250 strlcpy(hdr.ruleset, ruleset->anchor->name, 251 sizeof(hdr.ruleset)); 252 } 253 if (rm->log & PF_LOG_SOCKET_LOOKUP && !pd->lookup.done) 254 pd->lookup.done = pf_socket_lookup(dir, pd); 255 if (pd->lookup.done > 0) { 256 hdr.uid = pd->lookup.uid; 257 hdr.pid = pd->lookup.pid; 258 } else { 259 hdr.uid = UID_MAX; 260 hdr.pid = NO_PID; 261 } 262 hdr.rule_uid = rm->cuid; 263 hdr.rule_pid = rm->cpid; 264 hdr.dir = dir; 265 266 #ifdef INET 267 if (af == AF_INET) { 268 struct ip *ip; 269 ip = mtod(m, struct ip *); 270 ip->ip_len = htons(ip->ip_len); 271 ip->ip_off = htons(ip->ip_off); 272 273 if (dir == PF_OUT) { 274 ip->ip_sum = 0; 275 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 276 } 277 } 278 #endif /* INET */ 279 280 ifn->if_opackets++; 281 ifn->if_obytes += m->m_pkthdr.len; 282 bpf_mtap_hdr(ifn->if_bpf, (char *)&hdr, PFLOG_HDRLEN, m, 283 BPF_DIRECTION_OUT); 284 285 #ifdef INET 286 if (af == AF_INET) { 287 struct ip *ip = mtod(m, struct ip *); 288 289 ip->ip_len = ntohs(ip->ip_len); 290 ip->ip_off = ntohs(ip->ip_off); 291 } 292 #endif /* INET */ 293 294 return (0); 295 } 296 297 static int 298 pflog_modevent(module_t mod, int type, void *data) 299 { 300 int error = 0; 301 302 switch (type) { 303 case MOD_LOAD: 304 LIST_INIT(&pflogif_list); 305 if_clone_attach(&pflog_cloner); 306 break; 307 308 case MOD_UNLOAD: 309 if_clone_detach(&pflog_cloner); 310 while (!LIST_EMPTY(&pflogif_list)) { 311 pflog_clone_destroy( 312 &LIST_FIRST(&pflogif_list)->sc_if); 313 } 314 break; 315 316 default: 317 error = EINVAL; 318 break; 319 } 320 321 return error; 322 } 323 324 static moduledata_t pflog_mod = { 325 "pflog", 326 pflog_modevent, 327 0 328 }; 329 330 #define PFLOG_MODVER 1 331 332 DECLARE_MODULE(pflog, pflog_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 333 MODULE_VERSION(pflog, PFLOG_MODVER); 334