1 /*-
2 * Copyright (c) 1999 Poul-Henning Kamp.
3 * Copyright (c) 2008 Bjoern A. Zeeb.
4 * Copyright (c) 2009 James Gritton.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 #include "opt_ddb.h"
31 #include "opt_inet.h"
32 #include "opt_inet6.h"
33
34 #include <sys/param.h>
35 #include <sys/types.h>
36 #include <sys/kernel.h>
37 #include <sys/systm.h>
38 #include <sys/errno.h>
39 #include <sys/sysproto.h>
40 #include <sys/malloc.h>
41 #include <sys/osd.h>
42 #include <sys/priv.h>
43 #include <sys/proc.h>
44 #include <sys/taskqueue.h>
45 #include <sys/fcntl.h>
46 #include <sys/jail.h>
47 #include <sys/lock.h>
48 #include <sys/mutex.h>
49 #include <sys/racct.h>
50 #include <sys/refcount.h>
51 #include <sys/sx.h>
52 #include <sys/namei.h>
53 #include <sys/mount.h>
54 #include <sys/queue.h>
55 #include <sys/socket.h>
56 #include <sys/syscallsubr.h>
57 #include <sys/sysctl.h>
58 #include <sys/vnode.h>
59
60 #include <net/if.h>
61 #include <net/vnet.h>
62
63 #include <netinet/in.h>
64
65 static void
prison_bcopy_primary_ip6(const struct prison * pr,struct in6_addr * ia6)66 prison_bcopy_primary_ip6(const struct prison *pr, struct in6_addr *ia6)
67 {
68
69 bcopy(prison_ip_get0(pr, PR_INET6), ia6, sizeof(struct in6_addr));
70 }
71
72 int
prison_qcmp_v6(const void * ip1,const void * ip2)73 prison_qcmp_v6(const void *ip1, const void *ip2)
74 {
75 const struct in6_addr *ia6a, *ia6b;
76 int i, rc;
77
78 ia6a = (const struct in6_addr *)ip1;
79 ia6b = (const struct in6_addr *)ip2;
80
81 rc = 0;
82 for (i = 0; rc == 0 && i < sizeof(struct in6_addr); i++) {
83 if (ia6a->s6_addr[i] > ia6b->s6_addr[i])
84 rc = 1;
85 else if (ia6a->s6_addr[i] < ia6b->s6_addr[i])
86 rc = -1;
87 }
88 return (rc);
89 }
90
91 bool
prison_valid_v6(const void * ip)92 prison_valid_v6(const void *ip)
93 {
94 const struct in6_addr *ia = ip;
95
96 return (!IN6_IS_ADDR_UNSPECIFIED(ia));
97 }
98
99 /*
100 * Pass back primary IPv6 address for this jail.
101 *
102 * If not restricted return success but do not alter the address. Caller has
103 * to make sure to initialize it correctly (e.g. IN6ADDR_ANY_INIT).
104 *
105 * Returns 0 on success, EAFNOSUPPORT if the jail doesn't allow IPv6.
106 */
107 int
prison_get_ip6(struct ucred * cred,struct in6_addr * ia6)108 prison_get_ip6(struct ucred *cred, struct in6_addr *ia6)
109 {
110 struct prison *pr;
111
112 KASSERT(cred != NULL, ("%s: cred is NULL", __func__));
113 KASSERT(ia6 != NULL, ("%s: ia6 is NULL", __func__));
114
115 pr = cred->cr_prison;
116 if (!(pr->pr_flags & PR_IP6))
117 return (0);
118 mtx_lock(&pr->pr_mtx);
119 if (!(pr->pr_flags & PR_IP6)) {
120 mtx_unlock(&pr->pr_mtx);
121 return (0);
122 }
123 if (pr->pr_addrs[PR_INET6] == NULL) {
124 mtx_unlock(&pr->pr_mtx);
125 return (EAFNOSUPPORT);
126 }
127
128 prison_bcopy_primary_ip6(pr, ia6);
129 mtx_unlock(&pr->pr_mtx);
130 return (0);
131 }
132
133 /*
134 * Return true if we should do proper source address selection or are not jailed.
135 * We will return false if we should bypass source address selection in favour
136 * of the primary jail IPv6 address. Only in this case *ia will be updated and
137 * returned in NBO.
138 * Return true, even in case this jail does not allow IPv6.
139 */
140 bool
prison_saddrsel_ip6(struct ucred * cred,struct in6_addr * ia6)141 prison_saddrsel_ip6(struct ucred *cred, struct in6_addr *ia6)
142 {
143 struct prison *pr;
144 struct in6_addr lia6;
145
146 KASSERT(cred != NULL, ("%s: cred is NULL", __func__));
147 KASSERT(ia6 != NULL, ("%s: ia6 is NULL", __func__));
148
149 if (!jailed(cred))
150 return (true);
151
152 pr = cred->cr_prison;
153 if (pr->pr_flags & PR_IP6_SADDRSEL)
154 return (true);
155
156 lia6 = in6addr_any;
157 if (prison_get_ip6(cred, &lia6) != 0)
158 return (true);
159 if (IN6_IS_ADDR_UNSPECIFIED(&lia6))
160 return (true);
161
162 bcopy(&lia6, ia6, sizeof(struct in6_addr));
163 return (false);
164 }
165
166 /*
167 * Return true if pr1 and pr2 have the same IPv6 address restrictions.
168 */
169 bool
prison_equal_ip6(struct prison * pr1,struct prison * pr2)170 prison_equal_ip6(struct prison *pr1, struct prison *pr2)
171 {
172
173 if (pr1 == pr2)
174 return (true);
175
176 while (pr1 != &prison0 &&
177 #ifdef VIMAGE
178 !(pr1->pr_flags & PR_VNET) &&
179 #endif
180 !(pr1->pr_flags & PR_IP6_USER))
181 pr1 = pr1->pr_parent;
182 while (pr2 != &prison0 &&
183 #ifdef VIMAGE
184 !(pr2->pr_flags & PR_VNET) &&
185 #endif
186 !(pr2->pr_flags & PR_IP6_USER))
187 pr2 = pr2->pr_parent;
188 return (pr1 == pr2);
189 }
190
191 /*
192 * Make sure our (source) address is set to something meaningful to this jail.
193 *
194 * v6only should be set based on (inp->inp_flags & IN6P_IPV6_V6ONLY != 0)
195 * when needed while binding.
196 *
197 * Returns 0 if jail doesn't restrict IPv6 or if address belongs to jail,
198 * EADDRNOTAVAIL if the address doesn't belong, or EAFNOSUPPORT if the jail
199 * doesn't allow IPv6.
200 */
201 int
prison_local_ip6(struct ucred * cred,struct in6_addr * ia6,int v6only)202 prison_local_ip6(struct ucred *cred, struct in6_addr *ia6, int v6only)
203 {
204 struct prison *pr;
205 int error;
206
207 KASSERT(cred != NULL, ("%s: cred is NULL", __func__));
208 KASSERT(ia6 != NULL, ("%s: ia6 is NULL", __func__));
209
210 pr = cred->cr_prison;
211 if (!(pr->pr_flags & PR_IP6))
212 return (0);
213 mtx_lock(&pr->pr_mtx);
214 if (!(pr->pr_flags & PR_IP6)) {
215 mtx_unlock(&pr->pr_mtx);
216 return (0);
217 }
218 if (pr->pr_addrs[PR_INET6] == NULL) {
219 mtx_unlock(&pr->pr_mtx);
220 return (EAFNOSUPPORT);
221 }
222
223 if (IN6_IS_ADDR_UNSPECIFIED(ia6)) {
224 /*
225 * In case there is only 1 IPv6 address, and v6only is true,
226 * then bind directly.
227 */
228 if (v6only != 0 && prison_ip_cnt(pr, PR_INET6) == 1)
229 prison_bcopy_primary_ip6(pr, ia6);
230 mtx_unlock(&pr->pr_mtx);
231 return (0);
232 }
233
234 error = prison_check_ip6_locked(pr, ia6);
235 if (error == EADDRNOTAVAIL && IN6_IS_ADDR_LOOPBACK(ia6)) {
236 prison_bcopy_primary_ip6(pr, ia6);
237 error = 0;
238 }
239
240 mtx_unlock(&pr->pr_mtx);
241 return (error);
242 }
243
244 /*
245 * Rewrite destination address in case we will connect to loopback address.
246 *
247 * Returns 0 on success, EAFNOSUPPORT if the jail doesn't allow IPv6.
248 */
249 int
prison_remote_ip6(struct ucred * cred,struct in6_addr * ia6)250 prison_remote_ip6(struct ucred *cred, struct in6_addr *ia6)
251 {
252 struct prison *pr;
253
254 KASSERT(cred != NULL, ("%s: cred is NULL", __func__));
255 KASSERT(ia6 != NULL, ("%s: ia6 is NULL", __func__));
256
257 pr = cred->cr_prison;
258 if (!(pr->pr_flags & PR_IP6))
259 return (0);
260 mtx_lock(&pr->pr_mtx);
261 if (!(pr->pr_flags & PR_IP6)) {
262 mtx_unlock(&pr->pr_mtx);
263 return (0);
264 }
265 if (pr->pr_addrs[PR_INET6] == NULL) {
266 mtx_unlock(&pr->pr_mtx);
267 return (EAFNOSUPPORT);
268 }
269
270 if (IN6_IS_ADDR_LOOPBACK(ia6) &&
271 prison_check_ip6_locked(pr, ia6) == EADDRNOTAVAIL) {
272 prison_bcopy_primary_ip6(pr, ia6);
273 mtx_unlock(&pr->pr_mtx);
274 return (0);
275 }
276
277 /*
278 * Return success because nothing had to be changed.
279 */
280 mtx_unlock(&pr->pr_mtx);
281 return (0);
282 }
283
284 /*
285 * Check if given address belongs to the jail referenced by cred/prison.
286 *
287 * Returns 0 if address belongs to jail,
288 * EADDRNOTAVAIL if the address doesn't belong to the jail.
289 */
290 int
prison_check_ip6_locked(const struct prison * pr,const struct in6_addr * ia6)291 prison_check_ip6_locked(const struct prison *pr, const struct in6_addr *ia6)
292 {
293
294 if (!(pr->pr_flags & PR_IP6))
295 return (0);
296
297 return (prison_ip_check(pr, PR_INET6, ia6));
298 }
299
300 int
prison_check_ip6(const struct ucred * cred,const struct in6_addr * ia6)301 prison_check_ip6(const struct ucred *cred, const struct in6_addr *ia6)
302 {
303 struct prison *pr;
304 int error;
305
306 KASSERT(cred != NULL, ("%s: cred is NULL", __func__));
307 KASSERT(ia6 != NULL, ("%s: ia6 is NULL", __func__));
308
309 pr = cred->cr_prison;
310 if (!(pr->pr_flags & PR_IP6))
311 return (0);
312 mtx_lock(&pr->pr_mtx);
313 if (!(pr->pr_flags & PR_IP6)) {
314 mtx_unlock(&pr->pr_mtx);
315 return (0);
316 }
317 if (pr->pr_addrs[PR_INET6] == NULL) {
318 mtx_unlock(&pr->pr_mtx);
319 return (EAFNOSUPPORT);
320 }
321
322 error = prison_check_ip6_locked(pr, ia6);
323 mtx_unlock(&pr->pr_mtx);
324 return (error);
325 }
326