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 * Copyright (c) 2010 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 53 #include <net/if.h> 54 #include <net/if_types.h> 55 #include <net/ifq_var.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 *, struct ifaltq_subque *); 92 int pflog_clone_create(struct if_clone *, int, caddr_t); 93 int 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 lwkt_gettoken(&pf_token); 118 119 if (unit >= PFLOGIFS_MAX) { 120 lwkt_reltoken(&pf_token); 121 return (EINVAL); 122 } 123 124 if ((pflogif = kmalloc(sizeof(*pflogif), 125 M_DEVBUF, M_WAITOK|M_ZERO)) == NULL) { 126 lwkt_reltoken(&pf_token); 127 return (ENOMEM); 128 } 129 130 pflogif->sc_unit = unit; 131 lwkt_reltoken(&pf_token); 132 ifp = &pflogif->sc_if; 133 ksnprintf(ifp->if_xname, sizeof ifp->if_xname, "pflog%d", unit); 134 ifp->if_softc = pflogif; 135 ifp->if_mtu = PFLOGMTU; 136 ifp->if_ioctl = pflogioctl; 137 ifp->if_output = pflogoutput; 138 ifp->if_start = pflogstart; 139 ifp->if_type = IFT_PFLOG; 140 ifq_set_maxlen(&ifp->if_snd, ifqmaxlen); 141 ifp->if_hdrlen = PFLOG_HDRLEN; 142 if_attach(ifp, NULL); 143 144 bpfattach(&pflogif->sc_if, DLT_PFLOG, PFLOG_HDRLEN); 145 lwkt_gettoken(&pf_token); 146 147 crit_enter(); 148 LIST_INSERT_HEAD(&pflogif_list, pflogif, sc_list); 149 pflogifs[unit] = ifp; 150 crit_exit(); 151 152 lwkt_reltoken(&pf_token); 153 return (0); 154 } 155 156 int 157 pflog_clone_destroy(struct ifnet *ifp) 158 { 159 struct pflog_softc *pflogif = ifp->if_softc; 160 161 lwkt_gettoken(&pf_token); 162 163 crit_enter(); 164 pflogifs[pflogif->sc_unit] = NULL; 165 LIST_REMOVE(pflogif, sc_list); 166 crit_exit(); 167 168 lwkt_reltoken(&pf_token); 169 #if NBPFILTER > 0 170 bpfdetach(ifp); 171 #endif 172 if_detach(ifp); 173 lwkt_gettoken(&pf_token); 174 kfree(pflogif, M_DEVBUF); 175 lwkt_reltoken(&pf_token); 176 177 return 0; 178 } 179 180 /* 181 * Start output on the pflog interface. 182 */ 183 void 184 pflogstart(struct ifnet *ifp, struct ifaltq_subque *ifsq) 185 { 186 struct mbuf *m; 187 188 ASSERT_ALTQ_SQ_DEFAULT(ifp, ifsq); 189 ASSERT_LWKT_TOKEN_HELD(&pf_token); 190 191 for (;;) { 192 m = ifsq_dequeue(ifsq); 193 if (m == NULL) 194 return; 195 else 196 m_freem(m); 197 } 198 } 199 200 int 201 pflogoutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, 202 struct rtentry *rt) 203 { 204 m_freem(m); 205 return (0); 206 } 207 208 /* ARGSUSED */ 209 void 210 pflogrtrequest(int cmd, struct rtentry *rt, struct sockaddr *sa) 211 { 212 if (rt) 213 rt->rt_rmx.rmx_mtu = PFLOGMTU; 214 } 215 216 /* ARGSUSED */ 217 int 218 pflogioctl(struct ifnet *ifp, u_long cmd, caddr_t data, struct ucred *cr) 219 { 220 221 lwkt_gettoken(&pf_token); 222 223 switch (cmd) { 224 case SIOCSIFFLAGS: 225 lwkt_reltoken(&pf_token); 226 if (ifp->if_flags & IFF_UP) 227 ifp->if_flags |= IFF_RUNNING; 228 else 229 ifp->if_flags &= ~IFF_RUNNING; 230 lwkt_gettoken(&pf_token); 231 break; 232 default: 233 lwkt_reltoken(&pf_token); 234 return (EINVAL); 235 } 236 237 lwkt_reltoken(&pf_token); 238 return (0); 239 } 240 241 int 242 pflog_packet(struct pfi_kif *kif, struct mbuf *m, sa_family_t af, u_int8_t dir, 243 u_int8_t reason, struct pf_rule *rm, struct pf_rule *am, 244 struct pf_ruleset *ruleset, struct pf_pdesc *pd) 245 { 246 struct ifnet *ifn = NULL; 247 struct pfloghdr hdr; 248 249 ASSERT_LWKT_TOKEN_HELD(&pf_token); 250 251 if (kif == NULL || m == NULL || rm == NULL) 252 return (-1); 253 254 if ((ifn = pflogifs[rm->logif]) == NULL || !ifn->if_bpf) 255 return (0); 256 257 bzero(&hdr, sizeof(hdr)); 258 hdr.length = PFLOG_REAL_HDRLEN; 259 hdr.af = af; 260 hdr.action = rm->action; 261 hdr.reason = reason; 262 memcpy(hdr.ifname, kif->pfik_name, sizeof(hdr.ifname)); 263 264 if (am == NULL) { 265 hdr.rulenr = htonl(rm->nr); 266 hdr.subrulenr = -1; 267 } else { 268 hdr.rulenr = htonl(am->nr); 269 hdr.subrulenr = htonl(rm->nr); 270 if (ruleset != NULL && ruleset->anchor != NULL) 271 strlcpy(hdr.ruleset, ruleset->anchor->name, 272 sizeof(hdr.ruleset)); 273 } 274 if (rm->log & PF_LOG_SOCKET_LOOKUP && !pd->lookup.done) 275 pd->lookup.done = pf_socket_lookup(dir, pd); 276 if (pd->lookup.done > 0) { 277 hdr.uid = pd->lookup.uid; 278 hdr.pid = pd->lookup.pid; 279 } else { 280 hdr.uid = UID_MAX; 281 hdr.pid = NO_PID; 282 } 283 hdr.rule_uid = rm->cuid; 284 hdr.rule_pid = rm->cpid; 285 hdr.dir = dir; 286 287 #ifdef INET 288 if (af == AF_INET) { 289 struct ip *ip; 290 ip = mtod(m, struct ip *); 291 ip->ip_len = htons(ip->ip_len); 292 ip->ip_off = htons(ip->ip_off); 293 294 if (dir == PF_OUT) { 295 ip->ip_sum = 0; 296 ip->ip_sum = in_cksum(m, ip->ip_hl << 2); 297 } 298 } 299 #endif /* INET */ 300 301 IFNET_STAT_INC(ifn, opackets, 1); 302 IFNET_STAT_INC(ifn, obytes, m->m_pkthdr.len); 303 if (ifn->if_bpf) { 304 bpf_gettoken(); 305 if (ifn->if_bpf) { 306 bpf_mtap_hdr(ifn->if_bpf, (char *)&hdr, PFLOG_HDRLEN, m, 307 BPF_DIRECTION_OUT); 308 } 309 bpf_reltoken(); 310 } 311 312 #ifdef INET 313 if (af == AF_INET) { 314 struct ip *ip = mtod(m, struct ip *); 315 316 ip->ip_len = ntohs(ip->ip_len); 317 ip->ip_off = ntohs(ip->ip_off); 318 } 319 #endif /* INET */ 320 321 return (0); 322 } 323 324 static int 325 pflog_modevent(module_t mod, int type, void *data) 326 { 327 int error = 0; 328 329 struct pflog_softc *pflogif, *tmp; 330 331 lwkt_gettoken(&pf_token); 332 333 switch (type) { 334 case MOD_LOAD: 335 LIST_INIT(&pflogif_list); 336 lwkt_reltoken(&pf_token); 337 if_clone_attach(&pflog_cloner); 338 lwkt_gettoken(&pf_token); 339 break; 340 341 case MOD_UNLOAD: 342 lwkt_reltoken(&pf_token); 343 if_clone_detach(&pflog_cloner); 344 LIST_FOREACH_MUTABLE(pflogif, &pflogif_list, sc_list, tmp) { 345 pflog_clone_destroy(&pflogif->sc_if); 346 } 347 lwkt_gettoken(&pf_token); 348 break; 349 350 default: 351 error = EINVAL; 352 break; 353 } 354 lwkt_reltoken(&pf_token); 355 return error; 356 } 357 358 static moduledata_t pflog_mod = { 359 "pflog", 360 pflog_modevent, 361 0 362 }; 363 364 DECLARE_MODULE(pflog, pflog_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 365 MODULE_VERSION(pflog, PFLOG_MODVER); 366