1/*-
2 * Copyright 2005, Gleb Smirnoff <glebius@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
| 1/*-
2 * Copyright 2005, Gleb Smirnoff <glebius@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
|
36#include <sys/socket.h>
37#include <sys/syslog.h>
38
39#include <net/if.h>
40
41#include <netinet/in.h>
42#include <netinet/in_systm.h>
43#include <netinet/in_var.h>
44#include <netinet/ip_fw.h>
45#include <netinet/ip.h>
46#include <netinet/ip_var.h>
47
48#include <netgraph/ng_message.h>
49#include <netgraph/ng_parse.h>
50#include <netgraph/ng_ipfw.h>
51#include <netgraph/netgraph.h>
52
53static int ng_ipfw_mod_event(module_t mod, int event, void *data);
54static ng_constructor_t ng_ipfw_constructor;
55static ng_shutdown_t ng_ipfw_shutdown;
56static ng_newhook_t ng_ipfw_newhook;
57static ng_connect_t ng_ipfw_connect;
58static ng_findhook_t ng_ipfw_findhook;
59static ng_rcvdata_t ng_ipfw_rcvdata;
60static ng_disconnect_t ng_ipfw_disconnect;
61
62static hook_p ng_ipfw_findhook1(node_p, u_int16_t );
63static int ng_ipfw_input(struct mbuf **, int, struct ip_fw_args *,
64 int);
65
66/* We have only one node */
67static node_p fw_node;
68
69/* Netgraph node type descriptor */
70static struct ng_type ng_ipfw_typestruct = {
71 .version = NG_ABI_VERSION,
72 .name = NG_IPFW_NODE_TYPE,
73 .mod_event = ng_ipfw_mod_event,
74 .constructor = ng_ipfw_constructor,
75 .shutdown = ng_ipfw_shutdown,
76 .newhook = ng_ipfw_newhook,
77 .connect = ng_ipfw_connect,
78 .findhook = ng_ipfw_findhook,
79 .rcvdata = ng_ipfw_rcvdata,
80 .disconnect = ng_ipfw_disconnect,
81};
82NETGRAPH_INIT(ipfw, &ng_ipfw_typestruct);
83MODULE_DEPEND(ng_ipfw, ipfw, 2, 2, 2);
84
85/* Information we store for each hook */
86struct ng_ipfw_hook_priv {
87 hook_p hook;
88 u_int16_t rulenum;
89};
90typedef struct ng_ipfw_hook_priv *hpriv_p;
91
92static int
93ng_ipfw_mod_event(module_t mod, int event, void *data)
94{
95 int error = 0;
96
97 switch (event) {
98 case MOD_LOAD:
99
100 if (ng_ipfw_input_p != NULL) {
101 error = EEXIST;
102 break;
103 }
104
105 /* Setup node without any private data */
106 if ((error = ng_make_node_common(&ng_ipfw_typestruct, &fw_node))
107 != 0) {
108 log(LOG_ERR, "%s: can't create ng_ipfw node", __func__);
109 break;
110 };
111
112 /* Try to name node */
113 if (ng_name_node(fw_node, "ipfw") != 0)
114 log(LOG_WARNING, "%s: failed to name node \"ipfw\"",
115 __func__);
116
117 /* Register hook */
118 ng_ipfw_input_p = ng_ipfw_input;
119 break;
120
121 case MOD_UNLOAD:
122 /*
123 * This won't happen if a node exists.
124 * ng_ipfw_input_p is already cleared.
125 */
126 break;
127
128 default:
129 error = EOPNOTSUPP;
130 break;
131 }
132
133 return (error);
134}
135
136static int
137ng_ipfw_constructor(node_p node)
138{
139 return (EINVAL); /* Only one node */
140}
141
142static int
143ng_ipfw_newhook(node_p node, hook_p hook, const char *name)
144{
145 hpriv_p hpriv;
146 u_int16_t rulenum;
147 const char *cp;
148 char *endptr;
149
150 /* Protect from leading zero */
151 if (name[0] == '0' && name[1] != '\0')
152 return (EINVAL);
153
154 /* Check that name contains only digits */
155 for (cp = name; *cp != '\0'; cp++)
156 if (!isdigit(*cp))
157 return (EINVAL);
158
159 /* Convert it to integer */
160 rulenum = (u_int16_t)strtol(name, &endptr, 10);
161 if (*endptr != '\0')
162 return (EINVAL);
163
164 /* Allocate memory for this hook's private data */
165 hpriv = malloc(sizeof(*hpriv), M_NETGRAPH, M_NOWAIT | M_ZERO);
166 if (hpriv== NULL)
167 return (ENOMEM);
168
169 hpriv->hook = hook;
170 hpriv->rulenum = rulenum;
171
172 NG_HOOK_SET_PRIVATE(hook, hpriv);
173
174 return(0);
175}
176
177/*
178 * Set hooks into queueing mode, to avoid recursion between
179 * netgraph layer and ip_{input,output}.
180 */
181static int
182ng_ipfw_connect(hook_p hook)
183{
184 NG_HOOK_FORCE_QUEUE(hook);
185 return (0);
186}
187
188/* Look up hook by name */
189hook_p
190ng_ipfw_findhook(node_p node, const char *name)
191{
192 u_int16_t n; /* numeric representation of hook */
193 char *endptr;
194
195 n = (u_int16_t)strtol(name, &endptr, 10);
196 if (*endptr != '\0')
197 return NULL;
198 return ng_ipfw_findhook1(node, n);
199}
200
201/* Look up hook by rule number */
202static hook_p
203ng_ipfw_findhook1(node_p node, u_int16_t rulenum)
204{
205 hook_p hook;
206 hpriv_p hpriv;
207
208 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
209 hpriv = NG_HOOK_PRIVATE(hook);
210 if (NG_HOOK_IS_VALID(hook) && (hpriv->rulenum == rulenum))
211 return (hook);
212 }
213
214 return (NULL);
215}
216
217
218static int
219ng_ipfw_rcvdata(hook_p hook, item_p item)
220{
221 struct ng_ipfw_tag *ngit;
222 struct mbuf *m;
223
224 NGI_GET_M(item, m);
225 NG_FREE_ITEM(item);
226
227 if ((ngit = (struct ng_ipfw_tag *)m_tag_locate(m, NGM_IPFW_COOKIE, 0,
228 NULL)) == NULL) {
229 NG_FREE_M(m);
230 return (EINVAL); /* XXX: find smth better */
231 };
232
233 switch (ngit->dir) {
234 case NG_IPFW_OUT:
235 {
236 struct ip *ip;
237
238 if (m->m_len < sizeof(struct ip) &&
239 (m = m_pullup(m, sizeof(struct ip))) == NULL)
240 return (EINVAL);
241
242 ip = mtod(m, struct ip *);
243
244 ip->ip_len = ntohs(ip->ip_len);
245 ip->ip_off = ntohs(ip->ip_off);
246
247 return ip_output(m, NULL, NULL, IP_FORWARDING, NULL, NULL);
248 }
249 case NG_IPFW_IN:
250 ip_input(m);
251 return (0);
252 default:
253 panic("ng_ipfw_rcvdata: bad dir %u", ngit->dir);
254 }
255
256 /* not reached */
257 return (0);
258}
259
260static int
261ng_ipfw_input(struct mbuf **m0, int dir, struct ip_fw_args *fwa, int tee)
262{
263 struct mbuf *m;
264 struct ng_ipfw_tag *ngit;
265 struct ip *ip;
266 hook_p hook;
267 int error = 0;
268
269 /*
270 * Node must be loaded and corresponding hook must be present.
271 */
272 if (fw_node == NULL ||
273 (hook = ng_ipfw_findhook1(fw_node, fwa->cookie)) == NULL) {
274 if (tee == 0)
275 m_freem(*m0);
276 return (ESRCH); /* no hook associated with this rule */
277 }
278
279 /*
280 * We have two modes: in normal mode we add a tag to packet, which is
281 * important to return packet back to IP stack. In tee mode we make
282 * a copy of a packet and forward it into netgraph without a tag.
283 */
284 if (tee == 0) {
285 m = *m0;
286 *m0 = NULL; /* it belongs now to netgraph */
287
288 if ((ngit = (struct ng_ipfw_tag *)m_tag_alloc(NGM_IPFW_COOKIE,
289 0, TAGSIZ, M_NOWAIT|M_ZERO)) == NULL) {
290 m_freem(m);
291 return (ENOMEM);
292 }
293 ngit->rule = fwa->rule;
294 ngit->dir = dir;
295 ngit->ifp = fwa->oif;
296 m_tag_prepend(m, &ngit->mt);
297
298 } else
299 if ((m = m_dup(*m0, M_DONTWAIT)) == NULL)
300 return (ENOMEM); /* which is ignored */
301
302 if (m->m_len < sizeof(struct ip) &&
303 (m = m_pullup(m, sizeof(struct ip))) == NULL)
304 return (EINVAL);
305
306 ip = mtod(m, struct ip *);
307 ip->ip_len = htons(ip->ip_len);
308 ip->ip_off = htons(ip->ip_off);
309
310 NG_SEND_DATA_ONLY(error, hook, m);
311
312 return (error);
313}
314
315static int
316ng_ipfw_shutdown(node_p node)
317{
318
319 /*
320 * After our single node has been removed,
321 * the only thing that can be done is
322 * 'kldunload ng_ipfw.ko'
323 */
324 ng_ipfw_input_p = NULL;
325 NG_NODE_UNREF(node);
326 return (0);
327}
328
329static int
330ng_ipfw_disconnect(hook_p hook)
331{
332 const hpriv_p hpriv = NG_HOOK_PRIVATE(hook);
333
334 free(hpriv, M_NETGRAPH);
335 NG_HOOK_SET_PRIVATE(hook, NULL);
336
337 return (0);
338}
| 38#include <sys/socket.h>
39#include <sys/syslog.h>
40
41#include <net/if.h>
42
43#include <netinet/in.h>
44#include <netinet/in_systm.h>
45#include <netinet/in_var.h>
46#include <netinet/ip_fw.h>
47#include <netinet/ip.h>
48#include <netinet/ip_var.h>
49
50#include <netgraph/ng_message.h>
51#include <netgraph/ng_parse.h>
52#include <netgraph/ng_ipfw.h>
53#include <netgraph/netgraph.h>
54
55static int ng_ipfw_mod_event(module_t mod, int event, void *data);
56static ng_constructor_t ng_ipfw_constructor;
57static ng_shutdown_t ng_ipfw_shutdown;
58static ng_newhook_t ng_ipfw_newhook;
59static ng_connect_t ng_ipfw_connect;
60static ng_findhook_t ng_ipfw_findhook;
61static ng_rcvdata_t ng_ipfw_rcvdata;
62static ng_disconnect_t ng_ipfw_disconnect;
63
64static hook_p ng_ipfw_findhook1(node_p, u_int16_t );
65static int ng_ipfw_input(struct mbuf **, int, struct ip_fw_args *,
66 int);
67
68/* We have only one node */
69static node_p fw_node;
70
71/* Netgraph node type descriptor */
72static struct ng_type ng_ipfw_typestruct = {
73 .version = NG_ABI_VERSION,
74 .name = NG_IPFW_NODE_TYPE,
75 .mod_event = ng_ipfw_mod_event,
76 .constructor = ng_ipfw_constructor,
77 .shutdown = ng_ipfw_shutdown,
78 .newhook = ng_ipfw_newhook,
79 .connect = ng_ipfw_connect,
80 .findhook = ng_ipfw_findhook,
81 .rcvdata = ng_ipfw_rcvdata,
82 .disconnect = ng_ipfw_disconnect,
83};
84NETGRAPH_INIT(ipfw, &ng_ipfw_typestruct);
85MODULE_DEPEND(ng_ipfw, ipfw, 2, 2, 2);
86
87/* Information we store for each hook */
88struct ng_ipfw_hook_priv {
89 hook_p hook;
90 u_int16_t rulenum;
91};
92typedef struct ng_ipfw_hook_priv *hpriv_p;
93
94static int
95ng_ipfw_mod_event(module_t mod, int event, void *data)
96{
97 int error = 0;
98
99 switch (event) {
100 case MOD_LOAD:
101
102 if (ng_ipfw_input_p != NULL) {
103 error = EEXIST;
104 break;
105 }
106
107 /* Setup node without any private data */
108 if ((error = ng_make_node_common(&ng_ipfw_typestruct, &fw_node))
109 != 0) {
110 log(LOG_ERR, "%s: can't create ng_ipfw node", __func__);
111 break;
112 };
113
114 /* Try to name node */
115 if (ng_name_node(fw_node, "ipfw") != 0)
116 log(LOG_WARNING, "%s: failed to name node \"ipfw\"",
117 __func__);
118
119 /* Register hook */
120 ng_ipfw_input_p = ng_ipfw_input;
121 break;
122
123 case MOD_UNLOAD:
124 /*
125 * This won't happen if a node exists.
126 * ng_ipfw_input_p is already cleared.
127 */
128 break;
129
130 default:
131 error = EOPNOTSUPP;
132 break;
133 }
134
135 return (error);
136}
137
138static int
139ng_ipfw_constructor(node_p node)
140{
141 return (EINVAL); /* Only one node */
142}
143
144static int
145ng_ipfw_newhook(node_p node, hook_p hook, const char *name)
146{
147 hpriv_p hpriv;
148 u_int16_t rulenum;
149 const char *cp;
150 char *endptr;
151
152 /* Protect from leading zero */
153 if (name[0] == '0' && name[1] != '\0')
154 return (EINVAL);
155
156 /* Check that name contains only digits */
157 for (cp = name; *cp != '\0'; cp++)
158 if (!isdigit(*cp))
159 return (EINVAL);
160
161 /* Convert it to integer */
162 rulenum = (u_int16_t)strtol(name, &endptr, 10);
163 if (*endptr != '\0')
164 return (EINVAL);
165
166 /* Allocate memory for this hook's private data */
167 hpriv = malloc(sizeof(*hpriv), M_NETGRAPH, M_NOWAIT | M_ZERO);
168 if (hpriv== NULL)
169 return (ENOMEM);
170
171 hpriv->hook = hook;
172 hpriv->rulenum = rulenum;
173
174 NG_HOOK_SET_PRIVATE(hook, hpriv);
175
176 return(0);
177}
178
179/*
180 * Set hooks into queueing mode, to avoid recursion between
181 * netgraph layer and ip_{input,output}.
182 */
183static int
184ng_ipfw_connect(hook_p hook)
185{
186 NG_HOOK_FORCE_QUEUE(hook);
187 return (0);
188}
189
190/* Look up hook by name */
191hook_p
192ng_ipfw_findhook(node_p node, const char *name)
193{
194 u_int16_t n; /* numeric representation of hook */
195 char *endptr;
196
197 n = (u_int16_t)strtol(name, &endptr, 10);
198 if (*endptr != '\0')
199 return NULL;
200 return ng_ipfw_findhook1(node, n);
201}
202
203/* Look up hook by rule number */
204static hook_p
205ng_ipfw_findhook1(node_p node, u_int16_t rulenum)
206{
207 hook_p hook;
208 hpriv_p hpriv;
209
210 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
211 hpriv = NG_HOOK_PRIVATE(hook);
212 if (NG_HOOK_IS_VALID(hook) && (hpriv->rulenum == rulenum))
213 return (hook);
214 }
215
216 return (NULL);
217}
218
219
220static int
221ng_ipfw_rcvdata(hook_p hook, item_p item)
222{
223 struct ng_ipfw_tag *ngit;
224 struct mbuf *m;
225
226 NGI_GET_M(item, m);
227 NG_FREE_ITEM(item);
228
229 if ((ngit = (struct ng_ipfw_tag *)m_tag_locate(m, NGM_IPFW_COOKIE, 0,
230 NULL)) == NULL) {
231 NG_FREE_M(m);
232 return (EINVAL); /* XXX: find smth better */
233 };
234
235 switch (ngit->dir) {
236 case NG_IPFW_OUT:
237 {
238 struct ip *ip;
239
240 if (m->m_len < sizeof(struct ip) &&
241 (m = m_pullup(m, sizeof(struct ip))) == NULL)
242 return (EINVAL);
243
244 ip = mtod(m, struct ip *);
245
246 ip->ip_len = ntohs(ip->ip_len);
247 ip->ip_off = ntohs(ip->ip_off);
248
249 return ip_output(m, NULL, NULL, IP_FORWARDING, NULL, NULL);
250 }
251 case NG_IPFW_IN:
252 ip_input(m);
253 return (0);
254 default:
255 panic("ng_ipfw_rcvdata: bad dir %u", ngit->dir);
256 }
257
258 /* not reached */
259 return (0);
260}
261
262static int
263ng_ipfw_input(struct mbuf **m0, int dir, struct ip_fw_args *fwa, int tee)
264{
265 struct mbuf *m;
266 struct ng_ipfw_tag *ngit;
267 struct ip *ip;
268 hook_p hook;
269 int error = 0;
270
271 /*
272 * Node must be loaded and corresponding hook must be present.
273 */
274 if (fw_node == NULL ||
275 (hook = ng_ipfw_findhook1(fw_node, fwa->cookie)) == NULL) {
276 if (tee == 0)
277 m_freem(*m0);
278 return (ESRCH); /* no hook associated with this rule */
279 }
280
281 /*
282 * We have two modes: in normal mode we add a tag to packet, which is
283 * important to return packet back to IP stack. In tee mode we make
284 * a copy of a packet and forward it into netgraph without a tag.
285 */
286 if (tee == 0) {
287 m = *m0;
288 *m0 = NULL; /* it belongs now to netgraph */
289
290 if ((ngit = (struct ng_ipfw_tag *)m_tag_alloc(NGM_IPFW_COOKIE,
291 0, TAGSIZ, M_NOWAIT|M_ZERO)) == NULL) {
292 m_freem(m);
293 return (ENOMEM);
294 }
295 ngit->rule = fwa->rule;
296 ngit->dir = dir;
297 ngit->ifp = fwa->oif;
298 m_tag_prepend(m, &ngit->mt);
299
300 } else
301 if ((m = m_dup(*m0, M_DONTWAIT)) == NULL)
302 return (ENOMEM); /* which is ignored */
303
304 if (m->m_len < sizeof(struct ip) &&
305 (m = m_pullup(m, sizeof(struct ip))) == NULL)
306 return (EINVAL);
307
308 ip = mtod(m, struct ip *);
309 ip->ip_len = htons(ip->ip_len);
310 ip->ip_off = htons(ip->ip_off);
311
312 NG_SEND_DATA_ONLY(error, hook, m);
313
314 return (error);
315}
316
317static int
318ng_ipfw_shutdown(node_p node)
319{
320
321 /*
322 * After our single node has been removed,
323 * the only thing that can be done is
324 * 'kldunload ng_ipfw.ko'
325 */
326 ng_ipfw_input_p = NULL;
327 NG_NODE_UNREF(node);
328 return (0);
329}
330
331static int
332ng_ipfw_disconnect(hook_p hook)
333{
334 const hpriv_p hpriv = NG_HOOK_PRIVATE(hook);
335
336 free(hpriv, M_NETGRAPH);
337 NG_HOOK_SET_PRIVATE(hook, NULL);
338
339 return (0);
340}
|