1 /* $OpenBSD: filter.c,v 1.6 2007/08/01 09:31:41 henning Exp $ */
4 * Copyright (c) 2004, 2005 Camiel Dobbelaar, <cd@sentia.nl>
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19 #define _KERNEL_STRUCTURES
20 #include <sys/ioctl.h>
21 #include <sys/types.h>
22 #include <sys/socket.h>
25 #include <net/pf/pfvar.h>
26 #include <netinet/in.h>
27 #include <netinet/tcp.h>
28 #include <arpa/inet.h>
39 /* From netinet/in.h, but only _KERNEL_ gets them. */
40 #define satosin(sa) ((struct sockaddr_in *)(sa))
41 #define satosin6(sa) ((struct sockaddr_in6 *)(sa))
43 enum { TRANS_FILTER = 0, TRANS_NAT, TRANS_RDR, TRANS_SIZE };
45 int prepare_rule(u_int32_t, int, struct sockaddr *, struct sockaddr *,
47 int server_lookup4(struct sockaddr_in *, struct sockaddr_in *,
48 struct sockaddr_in *);
49 int server_lookup6(struct sockaddr_in6 *, struct sockaddr_in6 *,
50 struct sockaddr_in6 *);
52 static struct pfioc_pooladdr pfp;
53 static struct pfioc_rule pfr;
54 static struct pfioc_trans pft;
55 static struct pfioc_trans_e pfte[TRANS_SIZE];
56 static int dev, rule_log;
57 static char *qname, *tagname;
60 add_filter(u_int32_t id, u_int8_t dir, struct sockaddr *src,
61 struct sockaddr *dst, u_int16_t d_port)
63 if (!src || !dst || !d_port) {
68 if (prepare_rule(id, PF_RULESET_FILTER, src, dst, d_port) == -1)
71 pfr.rule.direction = dir;
72 if (ioctl(dev, DIOCADDRULE, &pfr) == -1)
79 add_nat(u_int32_t id, struct sockaddr *src, struct sockaddr *dst,
80 u_int16_t d_port, struct sockaddr *nat, u_int16_t nat_range_low,
81 u_int16_t nat_range_high)
83 if (!src || !dst || !d_port || !nat || !nat_range_low ||
84 (src->sa_family != nat->sa_family)) {
89 if (prepare_rule(id, PF_RULESET_NAT, src, dst, d_port) == -1)
92 if (nat->sa_family == AF_INET) {
93 memcpy(&pfp.addr.addr.v.a.addr.v4,
94 &satosin(nat)->sin_addr.s_addr, 4);
95 memset(&pfp.addr.addr.v.a.mask.addr8, 255, 4);
97 memcpy(&pfp.addr.addr.v.a.addr.v6,
98 &satosin6(nat)->sin6_addr.s6_addr, 16);
99 memset(&pfp.addr.addr.v.a.mask.addr8, 255, 16);
101 if (ioctl(dev, DIOCADDADDR, &pfp) == -1)
104 pfr.rule.rpool.proxy_port[0] = nat_range_low;
105 pfr.rule.rpool.proxy_port[1] = nat_range_high;
106 if (ioctl(dev, DIOCADDRULE, &pfr) == -1)
113 add_rdr(u_int32_t id, struct sockaddr *src, struct sockaddr *dst,
114 u_int16_t d_port, struct sockaddr *rdr, u_int16_t rdr_port)
116 if (!src || !dst || !d_port || !rdr || !rdr_port ||
117 (src->sa_family != rdr->sa_family)) {
122 if (prepare_rule(id, PF_RULESET_RDR, src, dst, d_port) == -1)
125 if (rdr->sa_family == AF_INET) {
126 memcpy(&pfp.addr.addr.v.a.addr.v4,
127 &satosin(rdr)->sin_addr.s_addr, 4);
128 memset(&pfp.addr.addr.v.a.mask.addr8, 255, 4);
130 memcpy(&pfp.addr.addr.v.a.addr.v6,
131 &satosin6(rdr)->sin6_addr.s6_addr, 16);
132 memset(&pfp.addr.addr.v.a.mask.addr8, 255, 16);
134 if (ioctl(dev, DIOCADDADDR, &pfp) == -1)
137 pfr.rule.rpool.proxy_port[0] = rdr_port;
138 if (ioctl(dev, DIOCADDRULE, &pfr) == -1)
147 if (ioctl(dev, DIOCXCOMMIT, &pft) == -1)
156 if (ioctl(dev, DIOCXROLLBACK, &pft) == -1)
163 init_filter(char *opt_qname, char *opt_tagname, int opt_verbose)
165 struct pf_status status;
168 tagname = opt_tagname;
170 if (opt_verbose == 1)
172 else if (opt_verbose == 2)
173 rule_log = PF_LOG_ALL;
175 dev = open("/dev/pf", O_RDWR);
178 if (ioctl(dev, DIOCGETSTATUS, &status) == -1)
179 err(1, "DIOCGETSTATUS");
181 errx(1, "pf is disabled");
185 prepare_commit(u_int32_t id)
187 char an[PF_ANCHOR_NAME_SIZE];
190 memset(&pft, 0, sizeof pft);
191 pft.size = TRANS_SIZE;
192 pft.esize = sizeof pfte[0];
195 snprintf(an, PF_ANCHOR_NAME_SIZE, "%s/%d.%d", FTP_PROXY_ANCHOR,
197 for (i = 0; i < TRANS_SIZE; i++) {
198 memset(&pfte[i], 0, sizeof pfte[0]);
199 strlcpy(pfte[i].anchor, an, PF_ANCHOR_NAME_SIZE);
202 pfte[i].rs_num = PF_RULESET_FILTER;
205 pfte[i].rs_num = PF_RULESET_NAT;
208 pfte[i].rs_num = PF_RULESET_RDR;
216 if (ioctl(dev, DIOCXBEGIN, &pft) == -1)
223 prepare_rule(u_int32_t id, int rs_num, struct sockaddr *src,
224 struct sockaddr *dst, u_int16_t d_port)
226 char an[PF_ANCHOR_NAME_SIZE];
228 if ((src->sa_family != AF_INET && src->sa_family != AF_INET6) ||
229 (src->sa_family != dst->sa_family)) {
230 errno = EPROTONOSUPPORT;
234 memset(&pfp, 0, sizeof pfp);
235 memset(&pfr, 0, sizeof pfr);
236 snprintf(an, PF_ANCHOR_NAME_SIZE, "%s/%d.%d", FTP_PROXY_ANCHOR,
238 strlcpy(pfp.anchor, an, PF_ANCHOR_NAME_SIZE);
239 strlcpy(pfr.anchor, an, PF_ANCHOR_NAME_SIZE);
242 case PF_RULESET_FILTER:
243 pfr.ticket = pfte[TRANS_FILTER].ticket;
246 pfr.ticket = pfte[TRANS_NAT].ticket;
249 pfr.ticket = pfte[TRANS_RDR].ticket;
255 if (ioctl(dev, DIOCBEGINADDRS, &pfp) == -1)
257 pfr.pool_ticket = pfp.ticket;
259 /* Generic for all rule types. */
260 pfr.rule.af = src->sa_family;
261 pfr.rule.proto = IPPROTO_TCP;
262 pfr.rule.src.addr.type = PF_ADDR_ADDRMASK;
263 pfr.rule.dst.addr.type = PF_ADDR_ADDRMASK;
264 if (src->sa_family == AF_INET) {
265 memcpy(&pfr.rule.src.addr.v.a.addr.v4,
266 &satosin(src)->sin_addr.s_addr, 4);
267 memset(&pfr.rule.src.addr.v.a.mask.addr8, 255, 4);
268 memcpy(&pfr.rule.dst.addr.v.a.addr.v4,
269 &satosin(dst)->sin_addr.s_addr, 4);
270 memset(&pfr.rule.dst.addr.v.a.mask.addr8, 255, 4);
272 memcpy(&pfr.rule.src.addr.v.a.addr.v6,
273 &satosin6(src)->sin6_addr.s6_addr, 16);
274 memset(&pfr.rule.src.addr.v.a.mask.addr8, 255, 16);
275 memcpy(&pfr.rule.dst.addr.v.a.addr.v6,
276 &satosin6(dst)->sin6_addr.s6_addr, 16);
277 memset(&pfr.rule.dst.addr.v.a.mask.addr8, 255, 16);
279 pfr.rule.dst.port_op = PF_OP_EQ;
280 pfr.rule.dst.port[0] = htons(d_port);
282 strlcpy(pfr.rule.tagname, tagname, sizeof pfr.rule.tagname);
285 case PF_RULESET_FILTER:
287 * pass quick [log] inet[6] proto tcp \
288 * from $src to $dst port = $d_port flags S/SA keep state
289 * (max 1) [queue qname]
291 pfr.rule.action = PF_PASS;
293 pfr.rule.log = rule_log;
294 pfr.rule.keep_state = 1;
295 pfr.rule.flags = TH_SYN;
296 pfr.rule.flagset = (TH_SYN|TH_ACK);
297 pfr.rule.max_states = 1;
299 strlcpy(pfr.rule.qname, qname, sizeof pfr.rule.qname);
303 * nat inet[6] proto tcp from $src to $dst port $d_port -> $nat
305 pfr.rule.action = PF_NAT;
309 * rdr inet[6] proto tcp from $src to $dst port $d_port -> $rdr
311 pfr.rule.action = PF_RDR;
322 server_lookup(struct sockaddr *client, struct sockaddr *proxy,
323 struct sockaddr *server)
325 if (client->sa_family == AF_INET)
326 return (server_lookup4(satosin(client), satosin(proxy),
329 if (client->sa_family == AF_INET6)
330 return (server_lookup6(satosin6(client), satosin6(proxy),
333 errno = EPROTONOSUPPORT;
338 server_lookup4(struct sockaddr_in *client, struct sockaddr_in *proxy,
339 struct sockaddr_in *server)
341 struct pfioc_natlook pnl;
343 memset(&pnl, 0, sizeof pnl);
344 pnl.direction = PF_OUT;
346 pnl.proto = IPPROTO_TCP;
347 memcpy(&pnl.saddr.v4, &client->sin_addr.s_addr, sizeof pnl.saddr.v4);
348 memcpy(&pnl.daddr.v4, &proxy->sin_addr.s_addr, sizeof pnl.daddr.v4);
349 pnl.sport = client->sin_port;
350 pnl.dport = proxy->sin_port;
352 if (ioctl(dev, DIOCNATLOOK, &pnl) == -1)
355 memset(server, 0, sizeof(struct sockaddr_in));
356 server->sin_len = sizeof(struct sockaddr_in);
357 server->sin_family = AF_INET;
358 memcpy(&server->sin_addr.s_addr, &pnl.rdaddr.v4,
359 sizeof server->sin_addr.s_addr);
360 server->sin_port = pnl.rdport;
366 server_lookup6(struct sockaddr_in6 *client, struct sockaddr_in6 *proxy,
367 struct sockaddr_in6 *server)
369 struct pfioc_natlook pnl;
371 memset(&pnl, 0, sizeof pnl);
372 pnl.direction = PF_OUT;
374 pnl.proto = IPPROTO_TCP;
375 memcpy(&pnl.saddr.v6, &client->sin6_addr.s6_addr, sizeof pnl.saddr.v6);
376 memcpy(&pnl.daddr.v6, &proxy->sin6_addr.s6_addr, sizeof pnl.daddr.v6);
377 pnl.sport = client->sin6_port;
378 pnl.dport = proxy->sin6_port;
380 if (ioctl(dev, DIOCNATLOOK, &pnl) == -1)
383 memset(server, 0, sizeof(struct sockaddr_in6));
384 server->sin6_len = sizeof(struct sockaddr_in6);
385 server->sin6_family = AF_INET6;
386 memcpy(&server->sin6_addr.s6_addr, &pnl.rdaddr.v6,
387 sizeof server->sin6_addr);
388 server->sin6_port = pnl.rdport;