xref: /netbsd-src/sys/net/npf/npf.c (revision a4ddc2c8fb9af816efe3b1c375a5530aef0e89e9)
1 /*	$NetBSD: npf.c,v 1.15 2013/02/09 03:35:31 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 1.15 2013/02/09 03:35:31 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_tableset_sysinit();
92 	npf_session_sysinit();
93 	npf_nat_sysinit();
94 	npf_alg_sysinit();
95 	npf_ext_sysinit();
96 
97 	/* Load empty configuration. */
98 	npf_config_init();
99 
100 #ifdef _MODULE
101 	/* Attach /dev/npf device. */
102 	error = devsw_attach("npf", NULL, &bmajor, &npf_cdevsw, &cmajor);
103 	if (error) {
104 		/* It will call devsw_detach(), which is safe. */
105 		(void)npf_fini();
106 	}
107 #endif
108 	return error;
109 }
110 
111 static int
112 npf_fini(void)
113 {
114 
115 	/* At first, detach device and remove pfil hooks. */
116 #ifdef _MODULE
117 	devsw_detach(NULL, &npf_cdevsw);
118 #endif
119 	npf_pfil_unregister();
120 
121 	/* Flush all sessions, destroy configuration (ruleset, etc). */
122 	npf_session_tracking(false);
123 	npf_config_fini();
124 
125 	/* Finally, safe to destroy the subsystems. */
126 	npf_ext_sysfini();
127 	npf_alg_sysfini();
128 	npf_nat_sysfini();
129 	npf_session_sysfini();
130 	npf_tableset_sysfini();
131 
132 	if (npf_sysctl) {
133 		sysctl_teardown(&npf_sysctl);
134 	}
135 	percpu_free(npf_stats_percpu, NPF_STATS_SIZE);
136 
137 	return 0;
138 }
139 
140 /*
141  * Module interface.
142  */
143 static int
144 npf_modcmd(modcmd_t cmd, void *arg)
145 {
146 
147 	switch (cmd) {
148 	case MODULE_CMD_INIT:
149 		return npf_init();
150 	case MODULE_CMD_FINI:
151 		return npf_fini();
152 	case MODULE_CMD_AUTOUNLOAD:
153 		if (npf_autounload_p()) {
154 			return EBUSY;
155 		}
156 		break;
157 	default:
158 		return ENOTTY;
159 	}
160 	return 0;
161 }
162 
163 void
164 npfattach(int nunits)
165 {
166 
167 	/* Void. */
168 }
169 
170 static int
171 npf_dev_open(dev_t dev, int flag, int mode, lwp_t *l)
172 {
173 
174 	/* Available only for super-user. */
175 	if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_FIREWALL,
176 	    KAUTH_REQ_NETWORK_FIREWALL_FW, NULL, NULL, NULL)) {
177 		return EPERM;
178 	}
179 	return 0;
180 }
181 
182 static int
183 npf_dev_close(dev_t dev, int flag, int mode, lwp_t *l)
184 {
185 
186 	return 0;
187 }
188 
189 static int
190 npf_dev_ioctl(dev_t dev, u_long cmd, void *data, int flag, lwp_t *l)
191 {
192 	int error;
193 
194 	/* Available only for super-user. */
195 	if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_FIREWALL,
196 	    KAUTH_REQ_NETWORK_FIREWALL_FW, NULL, NULL, NULL)) {
197 		return EPERM;
198 	}
199 
200 	switch (cmd) {
201 	case IOC_NPF_TABLE:
202 		error = npfctl_table(data);
203 		break;
204 	case IOC_NPF_RULE:
205 		error = npfctl_rule(cmd, data);
206 		break;
207 	case IOC_NPF_GETCONF:
208 		error = npfctl_getconf(cmd, data);
209 		break;
210 	case IOC_NPF_STATS:
211 		error = npfctl_stats(data);
212 		break;
213 	case IOC_NPF_SESSIONS_SAVE:
214 		error = npfctl_sessions_save(cmd, data);
215 		break;
216 	case IOC_NPF_SESSIONS_LOAD:
217 		error = npfctl_sessions_load(cmd, data);
218 		break;
219 	case IOC_NPF_SWITCH:
220 		error = npfctl_switch(data);
221 		break;
222 	case IOC_NPF_RELOAD:
223 		error = npfctl_reload(cmd, data);
224 		break;
225 	case IOC_NPF_VERSION:
226 		*(int *)data = NPF_VERSION;
227 		error = 0;
228 		break;
229 	default:
230 		error = ENOTTY;
231 		break;
232 	}
233 	return error;
234 }
235 
236 static int
237 npf_dev_poll(dev_t dev, int events, lwp_t *l)
238 {
239 
240 	return ENOTSUP;
241 }
242 
243 static int
244 npf_dev_read(dev_t dev, struct uio *uio, int flag)
245 {
246 
247 	return ENOTSUP;
248 }
249 
250 bool
251 npf_autounload_p(void)
252 {
253 	return !npf_pfil_registered_p() && npf_default_pass();
254 }
255 
256 /*
257  * NPF statistics interface.
258  */
259 
260 void
261 npf_stats_inc(npf_stats_t st)
262 {
263 	uint64_t *stats = percpu_getref(npf_stats_percpu);
264 	stats[st]++;
265 	percpu_putref(npf_stats_percpu);
266 }
267 
268 void
269 npf_stats_dec(npf_stats_t st)
270 {
271 	uint64_t *stats = percpu_getref(npf_stats_percpu);
272 	stats[st]--;
273 	percpu_putref(npf_stats_percpu);
274 }
275 
276 static void
277 npf_stats_collect(void *mem, void *arg, struct cpu_info *ci)
278 {
279 	uint64_t *percpu_stats = mem, *full_stats = arg;
280 	int i;
281 
282 	for (i = 0; i < NPF_STATS_COUNT; i++) {
283 		full_stats[i] += percpu_stats[i];
284 	}
285 }
286 
287 /*
288  * npfctl_stats: export collected statistics.
289  */
290 static int
291 npfctl_stats(void *data)
292 {
293 	uint64_t *fullst, *uptr = *(uint64_t **)data;
294 	int error;
295 
296 	fullst = kmem_zalloc(NPF_STATS_SIZE, KM_SLEEP);
297 	percpu_foreach(npf_stats_percpu, npf_stats_collect, fullst);
298 	error = copyout(fullst, uptr, NPF_STATS_SIZE);
299 	kmem_free(fullst, NPF_STATS_SIZE);
300 	return error;
301 }
302