xref: /netbsd-src/sys/net/npf/npf.c (revision 6a493d6bc668897c91594964a732d38505b70cbb)
1 /*	$NetBSD: npf.c,v 1.18 2013/11/08 00:38:26 rmind Exp $	*/
2 
3 /*-
4  * Copyright (c) 2009-2013 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This material is based upon work partially supported by The
8  * NetBSD Foundation under a contract with Mindaugas Rasiukevicius.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * NPF main: dynamic load/initialisation and unload routines.
34  */
35 
36 #include <sys/cdefs.h>
37 __KERNEL_RCSID(0, "$NetBSD: npf.c,v 1.18 2013/11/08 00:38:26 rmind Exp $");
38 
39 #include <sys/param.h>
40 #include <sys/types.h>
41 
42 #include <sys/atomic.h>
43 #include <sys/conf.h>
44 #include <sys/kauth.h>
45 #include <sys/kmem.h>
46 #include <sys/lwp.h>
47 #include <sys/module.h>
48 #include <sys/percpu.h>
49 #include <sys/rwlock.h>
50 #include <sys/socketvar.h>
51 #include <sys/sysctl.h>
52 #include <sys/uio.h>
53 
54 #include "npf_impl.h"
55 
56 /*
57  * Module and device structures.
58  */
59 MODULE(MODULE_CLASS_DRIVER, npf, NULL);
60 
61 void		npfattach(int);
62 
63 static int	npf_fini(void);
64 static int	npf_dev_open(dev_t, int, int, lwp_t *);
65 static int	npf_dev_close(dev_t, int, int, lwp_t *);
66 static int	npf_dev_ioctl(dev_t, u_long, void *, int, lwp_t *);
67 static int	npf_dev_poll(dev_t, int, lwp_t *);
68 static int	npf_dev_read(dev_t, struct uio *, int);
69 
70 static int	npfctl_stats(void *);
71 
72 static percpu_t *		npf_stats_percpu	__read_mostly;
73 static struct sysctllog *	npf_sysctl		__read_mostly;
74 
75 const struct cdevsw npf_cdevsw = {
76 	npf_dev_open, npf_dev_close, npf_dev_read, nowrite, npf_dev_ioctl,
77 	nostop, notty, npf_dev_poll, nommap, nokqfilter, D_OTHER | D_MPSAFE
78 };
79 
80 static int
81 npf_init(void)
82 {
83 #ifdef _MODULE
84 	devmajor_t bmajor = NODEVMAJOR, cmajor = NODEVMAJOR;
85 #endif
86 	int error = 0;
87 
88 	npf_stats_percpu = percpu_alloc(NPF_STATS_SIZE);
89 	npf_sysctl = NULL;
90 
91 	npf_bpf_sysinit();
92 	npf_worker_sysinit();
93 	npf_tableset_sysinit();
94 	npf_session_sysinit();
95 	npf_nat_sysinit();
96 	npf_alg_sysinit();
97 	npf_ext_sysinit();
98 
99 	/* Load empty configuration. */
100 	npf_pfil_register(true);
101 	npf_config_init();
102 
103 #ifdef _MODULE
104 	/* Attach /dev/npf device. */
105 	error = devsw_attach("npf", NULL, &bmajor, &npf_cdevsw, &cmajor);
106 	if (error) {
107 		/* It will call devsw_detach(), which is safe. */
108 		(void)npf_fini();
109 	}
110 #endif
111 	return error;
112 }
113 
114 static int
115 npf_fini(void)
116 {
117 	/* At first, detach device and remove pfil hooks. */
118 #ifdef _MODULE
119 	devsw_detach(NULL, &npf_cdevsw);
120 #endif
121 	npf_pfil_unregister(true);
122 
123 	/* Flush all sessions, destroy configuration (ruleset, etc). */
124 	npf_session_tracking(false);
125 	npf_config_fini();
126 
127 	/* Finally, safe to destroy the subsystems. */
128 	npf_ext_sysfini();
129 	npf_alg_sysfini();
130 	npf_nat_sysfini();
131 	npf_session_sysfini();
132 	npf_tableset_sysfini();
133 	npf_bpf_sysfini();
134 
135 	/* Note: worker is the last. */
136 	npf_worker_sysfini();
137 
138 	if (npf_sysctl) {
139 		sysctl_teardown(&npf_sysctl);
140 	}
141 	percpu_free(npf_stats_percpu, NPF_STATS_SIZE);
142 
143 	return 0;
144 }
145 
146 /*
147  * Module interface.
148  */
149 static int
150 npf_modcmd(modcmd_t cmd, void *arg)
151 {
152 
153 	switch (cmd) {
154 	case MODULE_CMD_INIT:
155 		return npf_init();
156 	case MODULE_CMD_FINI:
157 		return npf_fini();
158 	case MODULE_CMD_AUTOUNLOAD:
159 		if (npf_autounload_p()) {
160 			return EBUSY;
161 		}
162 		break;
163 	default:
164 		return ENOTTY;
165 	}
166 	return 0;
167 }
168 
169 void
170 npfattach(int nunits)
171 {
172 
173 	/* Void. */
174 }
175 
176 static int
177 npf_dev_open(dev_t dev, int flag, int mode, lwp_t *l)
178 {
179 
180 	/* Available only for super-user. */
181 	if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_FIREWALL,
182 	    KAUTH_REQ_NETWORK_FIREWALL_FW, NULL, NULL, NULL)) {
183 		return EPERM;
184 	}
185 	return 0;
186 }
187 
188 static int
189 npf_dev_close(dev_t dev, int flag, int mode, lwp_t *l)
190 {
191 
192 	return 0;
193 }
194 
195 static int
196 npf_dev_ioctl(dev_t dev, u_long cmd, void *data, int flag, lwp_t *l)
197 {
198 	int error;
199 
200 	/* Available only for super-user. */
201 	if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_FIREWALL,
202 	    KAUTH_REQ_NETWORK_FIREWALL_FW, NULL, NULL, NULL)) {
203 		return EPERM;
204 	}
205 
206 	switch (cmd) {
207 	case IOC_NPF_TABLE:
208 		error = npfctl_table(data);
209 		break;
210 	case IOC_NPF_RULE:
211 		error = npfctl_rule(cmd, data);
212 		break;
213 	case IOC_NPF_GETCONF:
214 		error = npfctl_getconf(cmd, data);
215 		break;
216 	case IOC_NPF_STATS:
217 		error = npfctl_stats(data);
218 		break;
219 	case IOC_NPF_SESSIONS_SAVE:
220 		error = npfctl_sessions_save(cmd, data);
221 		break;
222 	case IOC_NPF_SESSIONS_LOAD:
223 		error = npfctl_sessions_load(cmd, data);
224 		break;
225 	case IOC_NPF_SWITCH:
226 		error = npfctl_switch(data);
227 		break;
228 	case IOC_NPF_RELOAD:
229 		error = npfctl_reload(cmd, data);
230 		break;
231 	case IOC_NPF_VERSION:
232 		*(int *)data = NPF_VERSION;
233 		error = 0;
234 		break;
235 	default:
236 		error = ENOTTY;
237 		break;
238 	}
239 	return error;
240 }
241 
242 static int
243 npf_dev_poll(dev_t dev, int events, lwp_t *l)
244 {
245 
246 	return ENOTSUP;
247 }
248 
249 static int
250 npf_dev_read(dev_t dev, struct uio *uio, int flag)
251 {
252 
253 	return ENOTSUP;
254 }
255 
256 bool
257 npf_autounload_p(void)
258 {
259 	return !npf_pfil_registered_p() && npf_default_pass();
260 }
261 
262 /*
263  * NPF statistics interface.
264  */
265 
266 void
267 npf_stats_inc(npf_stats_t st)
268 {
269 	uint64_t *stats = percpu_getref(npf_stats_percpu);
270 	stats[st]++;
271 	percpu_putref(npf_stats_percpu);
272 }
273 
274 void
275 npf_stats_dec(npf_stats_t st)
276 {
277 	uint64_t *stats = percpu_getref(npf_stats_percpu);
278 	stats[st]--;
279 	percpu_putref(npf_stats_percpu);
280 }
281 
282 static void
283 npf_stats_collect(void *mem, void *arg, struct cpu_info *ci)
284 {
285 	uint64_t *percpu_stats = mem, *full_stats = arg;
286 	int i;
287 
288 	for (i = 0; i < NPF_STATS_COUNT; i++) {
289 		full_stats[i] += percpu_stats[i];
290 	}
291 }
292 
293 /*
294  * npfctl_stats: export collected statistics.
295  */
296 static int
297 npfctl_stats(void *data)
298 {
299 	uint64_t *fullst, *uptr = *(uint64_t **)data;
300 	int error;
301 
302 	fullst = kmem_zalloc(NPF_STATS_SIZE, KM_SLEEP);
303 	percpu_foreach(npf_stats_percpu, npf_stats_collect, fullst);
304 	error = copyout(fullst, uptr, NPF_STATS_SIZE);
305 	kmem_free(fullst, NPF_STATS_SIZE);
306 	return error;
307 }
308