xref: /freebsd/sys/sys/jail.h (revision a3557ef0)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 1999 Poul-Henning Kamp.
5  * Copyright (c) 2009 James Gritton.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD$
30  */
31 
32 #ifndef _SYS_JAIL_H_
33 #define _SYS_JAIL_H_
34 
35 #ifdef _KERNEL
36 struct jail_v0 {
37 	u_int32_t	version;
38 	char		*path;
39 	char		*hostname;
40 	u_int32_t	ip_number;
41 };
42 #endif
43 
44 struct jail {
45 	uint32_t	version;
46 	char		*path;
47 	char		*hostname;
48 	char		*jailname;
49 	uint32_t	ip4s;
50 	uint32_t	ip6s;
51 	struct in_addr	*ip4;
52 	struct in6_addr	*ip6;
53 };
54 #define	JAIL_API_VERSION	2
55 
56 /*
57  * For all xprison structs, always keep the pr_version an int and
58  * the first variable so userspace can easily distinguish them.
59  */
60 #ifndef _KERNEL
61 struct xprison_v1 {
62 	int		 pr_version;
63 	int		 pr_id;
64 	char		 pr_path[MAXPATHLEN];
65 	char		 pr_host[MAXHOSTNAMELEN];
66 	u_int32_t	 pr_ip;
67 };
68 #endif
69 
70 struct xprison {
71 	int		 pr_version;
72 	int		 pr_id;
73 	int		 pr_state;
74 	cpusetid_t	 pr_cpusetid;
75 	char		 pr_path[MAXPATHLEN];
76 	char		 pr_host[MAXHOSTNAMELEN];
77 	char		 pr_name[MAXHOSTNAMELEN];
78 	uint32_t	 pr_ip4s;
79 	uint32_t	 pr_ip6s;
80 #if 0
81 	/*
82 	 * sizeof(xprison) will be malloced + size needed for all
83 	 * IPv4 and IPv6 addesses. Offsets are based numbers of addresses.
84 	 */
85 	struct in_addr	 pr_ip4[];
86 	struct in6_addr	 pr_ip6[];
87 #endif
88 };
89 #define	XPRISON_VERSION		3
90 
91 #define	PRISON_STATE_INVALID	0
92 #define	PRISON_STATE_ALIVE	1
93 #define	PRISON_STATE_DYING	2
94 
95 /*
96  * Flags for jail_set and jail_get.
97  */
98 #define	JAIL_CREATE	0x01	/* Create jail if it doesn't exist */
99 #define	JAIL_UPDATE	0x02	/* Update parameters of existing jail */
100 #define	JAIL_ATTACH	0x04	/* Attach to jail upon creation */
101 #define	JAIL_DYING	0x08	/* Allow getting a dying jail */
102 #define	JAIL_SET_MASK	0x0f
103 #define	JAIL_GET_MASK	0x08
104 
105 #define	JAIL_SYS_DISABLE	0
106 #define	JAIL_SYS_NEW		1
107 #define	JAIL_SYS_INHERIT	2
108 
109 #ifndef _KERNEL
110 
111 struct iovec;
112 
113 int jail(struct jail *);
114 int jail_set(struct iovec *, unsigned int, int);
115 int jail_get(struct iovec *, unsigned int, int);
116 int jail_attach(int);
117 int jail_remove(int);
118 
119 #else /* _KERNEL */
120 
121 #include <sys/queue.h>
122 #include <sys/sysctl.h>
123 #include <sys/lock.h>
124 #include <sys/mutex.h>
125 #include <sys/_task.h>
126 
127 #define JAIL_MAX	999999
128 
129 #ifdef MALLOC_DECLARE
130 MALLOC_DECLARE(M_PRISON);
131 #endif
132 #endif /* _KERNEL */
133 
134 #if defined(_KERNEL) || defined(_WANT_PRISON)
135 
136 #include <sys/osd.h>
137 
138 #define	HOSTUUIDLEN	64
139 #define	OSRELEASELEN	32
140 
141 struct racct;
142 struct prison_racct;
143 
144 /*
145  * This structure describes a prison.  It is pointed to by all struct
146  * ucreds's of the inmates.  pr_ref keeps track of them and is used to
147  * delete the struture when the last inmate is dead.
148  *
149  * Lock key:
150  *   (a) allprison_lock
151  *   (p) locked by pr_mtx
152  *   (c) set only during creation before the structure is shared, no mutex
153  *       required to read
154  */
155 struct prison {
156 	TAILQ_ENTRY(prison) pr_list;			/* (a) all prisons */
157 	int		 pr_id;				/* (c) prison id */
158 	int		 pr_ref;			/* (p) refcount */
159 	int		 pr_uref;			/* (p) user (alive) refcount */
160 	unsigned	 pr_flags;			/* (p) PR_* flags */
161 	LIST_HEAD(, prison) pr_children;		/* (a) list of child jails */
162 	LIST_ENTRY(prison) pr_sibling;			/* (a) next in parent's list */
163 	struct prison	*pr_parent;			/* (c) containing jail */
164 	struct mtx	 pr_mtx;
165 	struct task	 pr_task;			/* (c) destroy task */
166 	struct osd	 pr_osd;			/* (p) additional data */
167 	struct cpuset	*pr_cpuset;			/* (p) cpuset */
168 	struct vnet	*pr_vnet;			/* (c) network stack */
169 	struct vnode	*pr_root;			/* (c) vnode to rdir */
170 	int		 pr_ip4s;			/* (p) number of v4 IPs */
171 	int		 pr_ip6s;			/* (p) number of v6 IPs */
172 	struct in_addr	*pr_ip4;			/* (p) v4 IPs of jail */
173 	struct in6_addr	*pr_ip6;			/* (p) v6 IPs of jail */
174 	struct prison_racct *pr_prison_racct;		/* (c) racct jail proxy */
175 	void		*pr_sparep[3];
176 	int		 pr_childcount;			/* (a) number of child jails */
177 	int		 pr_childmax;			/* (p) maximum child jails */
178 	unsigned	 pr_allow;			/* (p) PR_ALLOW_* flags */
179 	int		 pr_securelevel;		/* (p) securelevel */
180 	int		 pr_enforce_statfs;		/* (p) statfs permission */
181 	int		 pr_devfs_rsnum;		/* (p) devfs ruleset */
182 	int		 pr_spare[3];
183 	int		 pr_osreldate;			/* (c) kern.osreldate value */
184 	unsigned long	 pr_hostid;			/* (p) jail hostid */
185 	char		 pr_name[MAXHOSTNAMELEN];	/* (p) admin jail name */
186 	char		 pr_path[MAXPATHLEN];		/* (c) chroot path */
187 	char		 pr_hostname[MAXHOSTNAMELEN];	/* (p) jail hostname */
188 	char		 pr_domainname[MAXHOSTNAMELEN];	/* (p) jail domainname */
189 	char		 pr_hostuuid[HOSTUUIDLEN];	/* (p) jail hostuuid */
190 	char		 pr_osrelease[OSRELEASELEN];	/* (c) kern.osrelease value */
191 };
192 
193 struct prison_racct {
194 	LIST_ENTRY(prison_racct) prr_next;
195 	char		prr_name[MAXHOSTNAMELEN];
196 	u_int		prr_refcount;
197 	struct racct	*prr_racct;
198 };
199 #endif /* _KERNEL || _WANT_PRISON */
200 
201 #ifdef _KERNEL
202 /* Flag bits set via options */
203 #define	PR_PERSIST	0x00000001	/* Can exist without processes */
204 #define	PR_HOST		0x00000002	/* Virtualize hostname et al */
205 #define	PR_IP4_USER	0x00000004	/* Restrict IPv4 addresses */
206 #define	PR_IP6_USER	0x00000008	/* Restrict IPv6 addresses */
207 #define	PR_VNET		0x00000010	/* Virtual network stack */
208 #define	PR_IP4_SADDRSEL	0x00000080	/* Do IPv4 src addr sel. or use the */
209 					/* primary jail address. */
210 #define	PR_IP6_SADDRSEL	0x00000100	/* Do IPv6 src addr sel. or use the */
211 					/* primary jail address. */
212 
213 /* Internal flag bits */
214 #define	PR_IP4		0x02000000	/* IPv4 restricted or disabled */
215 					/* by this jail or an ancestor */
216 #define	PR_IP6		0x04000000	/* IPv6 restricted or disabled */
217 					/* by this jail or an ancestor */
218 
219 /*
220  * Flags for pr_allow
221  * Bits not noted here may be used for dynamic allow.mount.xxxfs.
222  */
223 #define	PR_ALLOW_SET_HOSTNAME		0x00000001
224 #define	PR_ALLOW_SYSVIPC		0x00000002
225 #define	PR_ALLOW_RAW_SOCKETS		0x00000004
226 #define	PR_ALLOW_CHFLAGS		0x00000008
227 #define	PR_ALLOW_MOUNT			0x00000010
228 #define	PR_ALLOW_QUOTAS			0x00000020
229 #define	PR_ALLOW_SOCKET_AF		0x00000040
230 #define	PR_ALLOW_MLOCK			0x00000080
231 #define	PR_ALLOW_READ_MSGBUF		0x00000100
232 #define	PR_ALLOW_UNPRIV_DEBUG		0x00000200
233 #define	PR_ALLOW_RESERVED_PORTS		0x00008000
234 #define	PR_ALLOW_KMEM_ACCESS		0x00010000	/* reserved, not used yet */
235 #define	PR_ALLOW_ALL_STATIC		0x000183ff
236 
237 /*
238  * PR_ALLOW_DIFFERENCES determines which flags are able to be
239  * different between the parent and child jail upon creation.
240  */
241 #define	PR_ALLOW_DIFFERENCES		(PR_ALLOW_UNPRIV_DEBUG)
242 
243 /*
244  * OSD methods
245  */
246 #define	PR_METHOD_CREATE	0
247 #define	PR_METHOD_GET		1
248 #define	PR_METHOD_SET		2
249 #define	PR_METHOD_CHECK		3
250 #define	PR_METHOD_ATTACH	4
251 #define	PR_METHOD_REMOVE	5
252 #define	PR_MAXMETHOD		6
253 
254 /*
255  * Lock/unlock a prison.
256  * XXX These exist not so much for general convenience, but to be useable in
257  *     the FOREACH_PRISON_DESCENDANT_LOCKED macro which can't handle them in
258  *     non-function form as currently defined.
259  */
260 static __inline void
261 prison_lock(struct prison *pr)
262 {
263 
264 	mtx_lock(&pr->pr_mtx);
265 }
266 
267 static __inline void
268 prison_unlock(struct prison *pr)
269 {
270 
271 	mtx_unlock(&pr->pr_mtx);
272 }
273 
274 /* Traverse a prison's immediate children. */
275 #define	FOREACH_PRISON_CHILD(ppr, cpr)					\
276 	LIST_FOREACH(cpr, &(ppr)->pr_children, pr_sibling)
277 
278 /*
279  * Preorder traversal of all of a prison's descendants.
280  * This ugly loop allows the macro to be followed by a single block
281  * as expected in a looping primitive.
282  */
283 #define	FOREACH_PRISON_DESCENDANT(ppr, cpr, descend)			\
284 	for ((cpr) = (ppr), (descend) = 1;				\
285 	    ((cpr) = (((descend) && !LIST_EMPTY(&(cpr)->pr_children))	\
286 	      ? LIST_FIRST(&(cpr)->pr_children)				\
287 	      : ((cpr) == (ppr)						\
288 		 ? NULL							\
289 		 : (((descend) = LIST_NEXT(cpr, pr_sibling) != NULL)	\
290 		    ? LIST_NEXT(cpr, pr_sibling)			\
291 		    : (cpr)->pr_parent))));)				\
292 		if (!(descend))						\
293 			;						\
294 		else
295 
296 /*
297  * As above, but lock descendants on the way down and unlock on the way up.
298  */
299 #define	FOREACH_PRISON_DESCENDANT_LOCKED(ppr, cpr, descend)		\
300 	for ((cpr) = (ppr), (descend) = 1;				\
301 	    ((cpr) = (((descend) && !LIST_EMPTY(&(cpr)->pr_children))	\
302 	      ? LIST_FIRST(&(cpr)->pr_children)				\
303 	      : ((cpr) == (ppr)						\
304 		 ? NULL							\
305 		 : ((prison_unlock(cpr),				\
306 		    (descend) = LIST_NEXT(cpr, pr_sibling) != NULL)	\
307 		    ? LIST_NEXT(cpr, pr_sibling)			\
308 		    : (cpr)->pr_parent))));)				\
309 		if ((descend) ? (prison_lock(cpr), 0) : 1)		\
310 			;						\
311 		else
312 
313 /*
314  * As above, but also keep track of the level descended to.
315  */
316 #define	FOREACH_PRISON_DESCENDANT_LOCKED_LEVEL(ppr, cpr, descend, level)\
317 	for ((cpr) = (ppr), (descend) = 1, (level) = 0;			\
318 	    ((cpr) = (((descend) && !LIST_EMPTY(&(cpr)->pr_children))	\
319 	      ? (level++, LIST_FIRST(&(cpr)->pr_children))		\
320 	      : ((cpr) == (ppr)						\
321 		 ? NULL							\
322 		 : ((prison_unlock(cpr),				\
323 		    (descend) = LIST_NEXT(cpr, pr_sibling) != NULL)	\
324 		    ? LIST_NEXT(cpr, pr_sibling)			\
325 		    : (level--, (cpr)->pr_parent)))));)			\
326 		if ((descend) ? (prison_lock(cpr), 0) : 1)		\
327 			;						\
328 		else
329 
330 /*
331  * Attributes of the physical system, and the root of the jail tree.
332  */
333 extern struct	prison prison0;
334 
335 TAILQ_HEAD(prisonlist, prison);
336 extern struct	prisonlist allprison;
337 extern struct	sx allprison_lock;
338 
339 /*
340  * Sysctls to describe jail parameters.
341  */
342 SYSCTL_DECL(_security_jail_param);
343 
344 #define	SYSCTL_JAIL_PARAM(module, param, type, fmt, descr)		\
345     SYSCTL_PROC(_security_jail_param ## module, OID_AUTO, param,	\
346 	(type) | CTLFLAG_MPSAFE, NULL, 0, sysctl_jail_param, fmt, descr)
347 #define	SYSCTL_JAIL_PARAM_STRING(module, param, access, len, descr)	\
348     SYSCTL_PROC(_security_jail_param ## module, OID_AUTO, param,	\
349 	CTLTYPE_STRING | CTLFLAG_MPSAFE | (access), NULL, len,		\
350 	sysctl_jail_param, "A", descr)
351 #define	SYSCTL_JAIL_PARAM_STRUCT(module, param, access, len, fmt, descr)\
352     SYSCTL_PROC(_security_jail_param ## module, OID_AUTO, param,	\
353 	CTLTYPE_STRUCT | CTLFLAG_MPSAFE | (access), NULL, len,		\
354 	sysctl_jail_param, fmt, descr)
355 #define	SYSCTL_JAIL_PARAM_NODE(module, descr)				\
356     SYSCTL_NODE(_security_jail_param, OID_AUTO, module, CTLFLAG_MPSAFE,	\
357         0, descr)
358 #define	SYSCTL_JAIL_PARAM_SUBNODE(parent, module, descr)		\
359     SYSCTL_NODE(_security_jail_param_##parent, OID_AUTO, module, 	\
360         CTLFLAG_MPSAFE, 0, descr)
361 #define	SYSCTL_JAIL_PARAM_SYS_NODE(module, access, descr)		\
362     SYSCTL_JAIL_PARAM_NODE(module, descr);				\
363     SYSCTL_JAIL_PARAM(_##module, , CTLTYPE_INT | (access), "E,jailsys",	\
364 	descr)
365 
366 /*
367  * Kernel support functions for jail().
368  */
369 struct ucred;
370 struct mount;
371 struct sockaddr;
372 struct statfs;
373 struct vfsconf;
374 
375 /*
376  * Return 1 if the passed credential is in a jail, otherwise 0.
377  */
378 #define jailed(cred)	(cred->cr_prison != &prison0)
379 
380 int jailed_without_vnet(struct ucred *);
381 void getcredhostname(struct ucred *, char *, size_t);
382 void getcreddomainname(struct ucred *, char *, size_t);
383 void getcredhostuuid(struct ucred *, char *, size_t);
384 void getcredhostid(struct ucred *, unsigned long *);
385 void getjailname(struct ucred *cred, char *name, size_t len);
386 void prison0_init(void);
387 int prison_allow(struct ucred *, unsigned);
388 int prison_check(struct ucred *cred1, struct ucred *cred2);
389 int prison_owns_vnet(struct ucred *);
390 int prison_canseemount(struct ucred *cred, struct mount *mp);
391 void prison_enforce_statfs(struct ucred *cred, struct mount *mp,
392     struct statfs *sp);
393 struct prison *prison_find(int prid);
394 struct prison *prison_find_child(struct prison *, int);
395 struct prison *prison_find_name(struct prison *, const char *);
396 int prison_flag(struct ucred *, unsigned);
397 void prison_free(struct prison *pr);
398 void prison_free_locked(struct prison *pr);
399 void prison_hold(struct prison *pr);
400 void prison_hold_locked(struct prison *pr);
401 void prison_proc_hold(struct prison *);
402 void prison_proc_free(struct prison *);
403 int prison_ischild(struct prison *, struct prison *);
404 int prison_equal_ip4(struct prison *, struct prison *);
405 int prison_get_ip4(struct ucred *cred, struct in_addr *ia);
406 int prison_local_ip4(struct ucred *cred, struct in_addr *ia);
407 int prison_remote_ip4(struct ucred *cred, struct in_addr *ia);
408 int prison_check_ip4(const struct ucred *, const struct in_addr *);
409 int prison_check_ip4_locked(const struct prison *, const struct in_addr *);
410 int prison_saddrsel_ip4(struct ucred *, struct in_addr *);
411 int prison_restrict_ip4(struct prison *, struct in_addr *);
412 int prison_qcmp_v4(const void *, const void *);
413 #ifdef INET6
414 int prison_equal_ip6(struct prison *, struct prison *);
415 int prison_get_ip6(struct ucred *, struct in6_addr *);
416 int prison_local_ip6(struct ucred *, struct in6_addr *, int);
417 int prison_remote_ip6(struct ucred *, struct in6_addr *);
418 int prison_check_ip6(const struct ucred *, const struct in6_addr *);
419 int prison_check_ip6_locked(const struct prison *, const struct in6_addr *);
420 int prison_saddrsel_ip6(struct ucred *, struct in6_addr *);
421 int prison_restrict_ip6(struct prison *, struct in6_addr *);
422 int prison_qcmp_v6(const void *, const void *);
423 #endif
424 int prison_check_af(struct ucred *cred, int af);
425 int prison_if(struct ucred *cred, const struct sockaddr *sa);
426 char *prison_name(struct prison *, struct prison *);
427 int prison_priv_check(struct ucred *cred, int priv);
428 int sysctl_jail_param(SYSCTL_HANDLER_ARGS);
429 unsigned prison_add_allow(const char *prefix, const char *name,
430     const char *prefix_descr, const char *descr);
431 void prison_add_vfs(struct vfsconf *vfsp);
432 void prison_racct_foreach(void (*callback)(struct racct *racct,
433     void *arg2, void *arg3), void (*pre)(void), void (*post)(void),
434     void *arg2, void *arg3);
435 struct prison_racct *prison_racct_find(const char *name);
436 void prison_racct_hold(struct prison_racct *prr);
437 void prison_racct_free(struct prison_racct *prr);
438 
439 #endif /* _KERNEL */
440 #endif /* !_SYS_JAIL_H_ */
441