1 /* $NetBSD: if_pflog.c,v 1.22 2020/01/29 05:52:27 thorpej 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@tla.org),
6 * Angelos D. Keromytis (kermit@csd.uch.gr) and
7 * Niels Provos (provos@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 1.22 2020/01/29 05:52:27 thorpej Exp $");
40
41 #ifdef _KERNEL_OPT
42 #include "opt_inet.h"
43 #endif
44
45 #include "pflog.h"
46
47 #include <sys/param.h>
48 #include <sys/systm.h>
49 #include <sys/mbuf.h>
50 #include <sys/proc.h>
51 #include <sys/socket.h>
52 #include <sys/ioctl.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/pfvar.h>
74 #include <net/if_pflog.h>
75
76 #include "ioconf.h"
77
78 #define PFLOGMTU (32768 + MHLEN + MLEN)
79
80 #ifdef PFLOGDEBUG
81 #define DPRINTF(x) do { if (pflogdebug) printf x ; } while (0)
82 #else
83 #define DPRINTF(x)
84 #endif
85
86 #ifdef _MODULE
87 void pflogdetach(void);
88 #endif /* _MODULE */
89 int pflogoutput(struct ifnet *, struct mbuf *, const struct sockaddr *,
90 const struct rtentry *);
91 int pflogioctl(struct ifnet *, u_long, void *);
92 void pflogstart(struct ifnet *);
93 int pflog_clone_create(struct if_clone *, int);
94 int pflog_clone_destroy(struct ifnet *);
95
96 LIST_HEAD(, pflog_softc) pflogif_list;
97 struct if_clone pflog_cloner =
98 IF_CLONE_INITIALIZER("pflog", pflog_clone_create, pflog_clone_destroy);
99
100 struct ifnet *pflogifs[PFLOGIFS_MAX]; /* for fast access */
101
102 void
pflogattach(int npflog)103 pflogattach(int npflog)
104 {
105 int i;
106
107 LIST_INIT(&pflogif_list);
108 for (i = 0; i < PFLOGIFS_MAX; i++)
109 pflogifs[i] = NULL;
110 if_clone_attach(&pflog_cloner);
111 }
112
113 #ifdef _MODULE
114 void
pflogdetach(void)115 pflogdetach(void)
116 {
117 int i;
118
119 for (i = 0; i < PFLOGIFS_MAX; i++) {
120 if (pflogifs[i] != NULL)
121 pflog_clone_destroy(pflogifs[i]);
122 }
123 if_clone_detach(&pflog_cloner);
124 }
125 #endif /* _MODULE */
126
127 int
pflog_clone_create(struct if_clone * ifc,int unit)128 pflog_clone_create(struct if_clone *ifc, int unit)
129 {
130 struct ifnet *ifp;
131 struct pflog_softc *pflogif;
132 int s;
133
134 if (unit >= PFLOGIFS_MAX)
135 return (EINVAL);
136
137 if ((pflogif = malloc(sizeof(*pflogif), M_DEVBUF, M_NOWAIT|M_ZERO)) == NULL)
138 return (ENOMEM);
139
140 pflogif->sc_unit = unit;
141 ifp = &pflogif->sc_if;
142 snprintf(ifp->if_xname, sizeof ifp->if_xname, "pflog%d", unit);
143 ifp->if_softc = pflogif;
144 ifp->if_mtu = PFLOGMTU;
145 ifp->if_ioctl = pflogioctl;
146 ifp->if_output = pflogoutput;
147 ifp->if_start = pflogstart;
148 ifp->if_type = IFT_PFLOG;
149 #ifndef __NetBSD__
150 ifp->if_snd.ifq_maxlen = ifqmaxlen;
151 #endif /* !__NetBSD__ */
152 ifp->if_hdrlen = PFLOG_HDRLEN;
153 if_attach(ifp);
154 if_alloc_sadl(ifp);
155
156 #ifdef __NetBSD__
157 bpf_attach(ifp, DLT_PFLOG, PFLOG_HDRLEN);
158 #else
159 bpfattach(&pflogif->sc_if.if_bpf, ifp, DLT_PFLOG, PFLOG_HDRLEN);
160 #endif /* !__NetBSD__ */
161
162 s = splnet();
163 LIST_INSERT_HEAD(&pflogif_list, pflogif, sc_list);
164 pflogifs[unit] = ifp;
165 splx(s);
166
167 return (0);
168 }
169
170 int
pflog_clone_destroy(struct ifnet * ifp)171 pflog_clone_destroy(struct ifnet *ifp)
172 {
173 struct pflog_softc *pflogif = ifp->if_softc;
174 int s;
175
176 s = splnet();
177 pflogifs[pflogif->sc_unit] = NULL;
178 LIST_REMOVE(pflogif, sc_list);
179 splx(s);
180
181 bpf_detach(ifp);
182 if_detach(ifp);
183 free(pflogif, M_DEVBUF);
184 return (0);
185 }
186
187 /*
188 * Start output on the pflog interface.
189 */
190 void
pflogstart(struct ifnet * ifp)191 pflogstart(struct ifnet *ifp)
192 {
193 struct mbuf *m;
194 int s;
195
196 for (;;) {
197 s = splnet();
198 IF_DROP(&ifp->if_snd);
199 IF_DEQUEUE(&ifp->if_snd, m);
200 splx(s);
201
202 if (m == NULL)
203 return;
204 else
205 m_freem(m);
206 }
207 }
208
209 int
pflogoutput(struct ifnet * ifp,struct mbuf * m,const struct sockaddr * dst,const struct rtentry * rt)210 pflogoutput(struct ifnet *ifp, struct mbuf *m,
211 const struct sockaddr *dst, const struct rtentry *rt)
212 {
213 m_freem(m);
214 return (0);
215 }
216
217 /* ARGSUSED */
218 int
pflogioctl(struct ifnet * ifp,u_long cmd,void * data)219 pflogioctl(struct ifnet *ifp, u_long cmd, void *data)
220 {
221 int error = 0;
222
223 switch (cmd) {
224 case SIOCSIFFLAGS:
225 if ((error = ifioctl_common(ifp, cmd, data)) != 0)
226 break;
227 /*FALLTHROUGH*/
228 case SIOCINITIFADDR:
229 case SIOCAIFADDR:
230 case SIOCSIFDSTADDR:
231 if (ifp->if_flags & IFF_UP)
232 ifp->if_flags |= IFF_RUNNING;
233 else
234 ifp->if_flags &= ~IFF_RUNNING;
235 break;
236 default:
237 error = ifioctl_common(ifp, cmd, data);
238 }
239
240 return error;
241 }
242
243 int
pflog_packet(struct pfi_kif * kif,struct mbuf * m,sa_family_t af,u_int8_t dir,u_int8_t reason,struct pf_rule * rm,struct pf_rule * am,struct pf_ruleset * ruleset,struct pf_pdesc * pd)244 pflog_packet(struct pfi_kif *kif, struct mbuf *m, sa_family_t af, u_int8_t dir,
245 u_int8_t reason, struct pf_rule *rm, struct pf_rule *am,
246 struct pf_ruleset *ruleset, struct pf_pdesc *pd)
247 {
248 struct ifnet *ifn;
249 struct pfloghdr hdr;
250
251 if (kif == NULL || m == NULL || rm == NULL || pd == 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 && dir == PF_OUT) {
289 struct ip *ip;
290
291 ip = mtod(m, struct ip *);
292 ip->ip_sum = 0;
293 ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
294 }
295 #endif /* INET */
296
297 #ifdef __NetBSD__
298 if_statadd2(ifn, if_opackets, 1, if_obytes, m->m_pkthdr.len);
299 #else
300 ifn->if_opackets++;
301 ifn->if_obytes += m->m_pkthdr.len;
302 #endif /* __NetBSD__ */
303
304 #ifdef __NetBSD__
305 bpf_mtap2(ifn->if_bpf, &hdr, PFLOG_HDRLEN, m, BPF_D_OUT);
306 #else
307 bpf_mtap_hdr(ifn->if_bpf, (char *)&hdr, PFLOG_HDRLEN, m,
308 BPF_DIRECTION_OUT);
309 #endif /* !__NetBSD__ */
310
311
312 return (0);
313 }
314