xref: /f-stack/freebsd/sys/jail.h (revision 22ce4aff)
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 __BEGIN_DECLS
114 int jail(struct jail *);
115 int jail_set(struct iovec *, unsigned int, int);
116 int jail_get(struct iovec *, unsigned int, int);
117 int jail_attach(int);
118 int jail_remove(int);
119 __END_DECLS
120 
121 #else /* _KERNEL */
122 
123 #include <sys/queue.h>
124 #include <sys/sysctl.h>
125 #include <sys/lock.h>
126 #include <sys/mutex.h>
127 #include <sys/_task.h>
128 
129 #define JAIL_MAX	999999
130 
131 #ifdef MALLOC_DECLARE
132 MALLOC_DECLARE(M_PRISON);
133 #endif
134 #endif /* _KERNEL */
135 
136 #if defined(_KERNEL) || defined(_WANT_PRISON)
137 
138 #include <sys/osd.h>
139 
140 #define	HOSTUUIDLEN	64
141 #define	OSRELEASELEN	32
142 
143 struct racct;
144 struct prison_racct;
145 
146 /*
147  * This structure describes a prison.  It is pointed to by all struct
148  * ucreds's of the inmates.  pr_ref keeps track of them and is used to
149  * delete the struture when the last inmate is dead.
150  *
151  * Lock key:
152  *   (a) allprison_lock
153  *   (c) set only during creation before the structure is shared, no mutex
154  *       required to read
155  *   (m) locked by pr_mtx
156  *   (p) locked by pr_mtx, and also at least shared allprison_lock required
157  *       to update
158  *   (r) atomic via refcount(9), pr_mtx required to decrement to zero
159  */
160 struct prison {
161 	TAILQ_ENTRY(prison) pr_list;			/* (a) all prisons */
162 	int		 pr_id;				/* (c) prison id */
163 	volatile u_int	 pr_ref;			/* (r) refcount */
164 	volatile u_int	 pr_uref;			/* (r) user (alive) refcount */
165 	unsigned	 pr_flags;			/* (p) PR_* flags */
166 	LIST_HEAD(, prison) pr_children;		/* (a) list of child jails */
167 	LIST_ENTRY(prison) pr_sibling;			/* (a) next in parent's list */
168 	struct prison	*pr_parent;			/* (c) containing jail */
169 	struct mtx	 pr_mtx;
170 	struct task	 pr_task;			/* (c) destroy task */
171 	struct osd	 pr_osd;			/* (p) additional data */
172 	struct cpuset	*pr_cpuset;			/* (p) cpuset */
173 	struct vnet	*pr_vnet;			/* (c) network stack */
174 	struct vnode	*pr_root;			/* (c) vnode to rdir */
175 	int		 pr_ip4s;			/* (p) number of v4 IPs */
176 	int		 pr_ip6s;			/* (p) number of v6 IPs */
177 	struct in_addr	*pr_ip4;			/* (p) v4 IPs of jail */
178 	struct in6_addr	*pr_ip6;			/* (p) v6 IPs of jail */
179 	struct prison_racct *pr_prison_racct;		/* (c) racct jail proxy */
180 	void		*pr_sparep[3];
181 	int		 pr_childcount;			/* (a) number of child jails */
182 	int		 pr_childmax;			/* (p) maximum child jails */
183 	unsigned	 pr_allow;			/* (p) PR_ALLOW_* flags */
184 	int		 pr_securelevel;		/* (p) securelevel */
185 	int		 pr_enforce_statfs;		/* (p) statfs permission */
186 	int		 pr_devfs_rsnum;		/* (p) devfs ruleset */
187 	int		 pr_spare[3];
188 	int		 pr_osreldate;			/* (c) kern.osreldate value */
189 	unsigned long	 pr_hostid;			/* (p) jail hostid */
190 	char		 pr_name[MAXHOSTNAMELEN];	/* (p) admin jail name */
191 	char		 pr_path[MAXPATHLEN];		/* (c) chroot path */
192 	char		 pr_hostname[MAXHOSTNAMELEN];	/* (p) jail hostname */
193 	char		 pr_domainname[MAXHOSTNAMELEN];	/* (p) jail domainname */
194 	char		 pr_hostuuid[HOSTUUIDLEN];	/* (p) jail hostuuid */
195 	char		 pr_osrelease[OSRELEASELEN];	/* (c) kern.osrelease value */
196 };
197 
198 struct prison_racct {
199 	LIST_ENTRY(prison_racct) prr_next;
200 	char		prr_name[MAXHOSTNAMELEN];
201 	u_int		prr_refcount;
202 	struct racct	*prr_racct;
203 };
204 #endif /* _KERNEL || _WANT_PRISON */
205 
206 #ifdef _KERNEL
207 /* Flag bits set via options */
208 #define	PR_PERSIST	0x00000001	/* Can exist without processes */
209 #define	PR_HOST		0x00000002	/* Virtualize hostname et al */
210 #define	PR_IP4_USER	0x00000004	/* Restrict IPv4 addresses */
211 #define	PR_IP6_USER	0x00000008	/* Restrict IPv6 addresses */
212 #define	PR_VNET		0x00000010	/* Virtual network stack */
213 #define	PR_IP4_SADDRSEL	0x00000080	/* Do IPv4 src addr sel. or use the */
214 					/* primary jail address. */
215 #define	PR_IP6_SADDRSEL	0x00000100	/* Do IPv6 src addr sel. or use the */
216 					/* primary jail address. */
217 
218 /* Internal flag bits */
219 #define	PR_REMOVE	0x01000000	/* In process of being removed */
220 #define	PR_IP4		0x02000000	/* IPv4 restricted or disabled */
221 					/* by this jail or an ancestor */
222 #define	PR_IP6		0x04000000	/* IPv6 restricted or disabled */
223 					/* by this jail or an ancestor */
224 
225 /*
226  * Flags for pr_allow
227  * Bits not noted here may be used for dynamic allow.mount.xxxfs.
228  */
229 #define	PR_ALLOW_SET_HOSTNAME		0x00000001
230 #define	PR_ALLOW_SYSVIPC		0x00000002
231 #define	PR_ALLOW_RAW_SOCKETS		0x00000004
232 #define	PR_ALLOW_CHFLAGS		0x00000008
233 #define	PR_ALLOW_MOUNT			0x00000010
234 #define	PR_ALLOW_QUOTAS			0x00000020
235 #define	PR_ALLOW_SOCKET_AF		0x00000040
236 #define	PR_ALLOW_MLOCK			0x00000080
237 #define	PR_ALLOW_READ_MSGBUF		0x00000100
238 #define	PR_ALLOW_UNPRIV_DEBUG		0x00000200
239 #define	PR_ALLOW_SUSER			0x00000400
240 #define	PR_ALLOW_RESERVED_PORTS		0x00008000
241 #define	PR_ALLOW_KMEM_ACCESS		0x00010000	/* reserved, not used yet */
242 #define	PR_ALLOW_ALL_STATIC		0x000187ff
243 
244 /*
245  * PR_ALLOW_DIFFERENCES determines which flags are able to be
246  * different between the parent and child jail upon creation.
247  */
248 #define	PR_ALLOW_DIFFERENCES		(PR_ALLOW_UNPRIV_DEBUG)
249 
250 /*
251  * OSD methods
252  */
253 #define	PR_METHOD_CREATE	0
254 #define	PR_METHOD_GET		1
255 #define	PR_METHOD_SET		2
256 #define	PR_METHOD_CHECK		3
257 #define	PR_METHOD_ATTACH	4
258 #define	PR_METHOD_REMOVE	5
259 #define	PR_MAXMETHOD		6
260 
261 /*
262  * Lock/unlock a prison.
263  * XXX These exist not so much for general convenience, but to be useable in
264  *     the FOREACH_PRISON_DESCENDANT_LOCKED macro which can't handle them in
265  *     non-function form as currently defined.
266  */
267 static __inline void
prison_lock(struct prison * pr)268 prison_lock(struct prison *pr)
269 {
270 
271 	mtx_lock(&pr->pr_mtx);
272 }
273 
274 static __inline void
prison_unlock(struct prison * pr)275 prison_unlock(struct prison *pr)
276 {
277 
278 	mtx_unlock(&pr->pr_mtx);
279 }
280 
281 /* Traverse a prison's immediate children. */
282 #define	FOREACH_PRISON_CHILD(ppr, cpr)					\
283 	LIST_FOREACH(cpr, &(ppr)->pr_children, pr_sibling)
284 
285 /*
286  * Preorder traversal of all of a prison's descendants.
287  * This ugly loop allows the macro to be followed by a single block
288  * as expected in a looping primitive.
289  */
290 #define	FOREACH_PRISON_DESCENDANT(ppr, cpr, descend)			\
291 	for ((cpr) = (ppr), (descend) = 1;				\
292 	    ((cpr) = (((descend) && !LIST_EMPTY(&(cpr)->pr_children))	\
293 	      ? LIST_FIRST(&(cpr)->pr_children)				\
294 	      : ((cpr) == (ppr)						\
295 		 ? NULL							\
296 		 : (((descend) = LIST_NEXT(cpr, pr_sibling) != NULL)	\
297 		    ? LIST_NEXT(cpr, pr_sibling)			\
298 		    : (cpr)->pr_parent))));)				\
299 		if (!(descend))						\
300 			;						\
301 		else
302 
303 /*
304  * As above, but lock descendants on the way down and unlock on the way up.
305  */
306 #define	FOREACH_PRISON_DESCENDANT_LOCKED(ppr, cpr, descend)		\
307 	for ((cpr) = (ppr), (descend) = 1;				\
308 	    ((cpr) = (((descend) && !LIST_EMPTY(&(cpr)->pr_children))	\
309 	      ? LIST_FIRST(&(cpr)->pr_children)				\
310 	      : ((cpr) == (ppr)						\
311 		 ? NULL							\
312 		 : ((prison_unlock(cpr),				\
313 		    (descend) = LIST_NEXT(cpr, pr_sibling) != NULL)	\
314 		    ? LIST_NEXT(cpr, pr_sibling)			\
315 		    : (cpr)->pr_parent))));)				\
316 		if ((descend) ? (prison_lock(cpr), 0) : 1)		\
317 			;						\
318 		else
319 
320 /*
321  * As above, but also keep track of the level descended to.
322  */
323 #define	FOREACH_PRISON_DESCENDANT_LOCKED_LEVEL(ppr, cpr, descend, level)\
324 	for ((cpr) = (ppr), (descend) = 1, (level) = 0;			\
325 	    ((cpr) = (((descend) && !LIST_EMPTY(&(cpr)->pr_children))	\
326 	      ? (level++, LIST_FIRST(&(cpr)->pr_children))		\
327 	      : ((cpr) == (ppr)						\
328 		 ? NULL							\
329 		 : ((prison_unlock(cpr),				\
330 		    (descend) = LIST_NEXT(cpr, pr_sibling) != NULL)	\
331 		    ? LIST_NEXT(cpr, pr_sibling)			\
332 		    : (level--, (cpr)->pr_parent)))));)			\
333 		if ((descend) ? (prison_lock(cpr), 0) : 1)		\
334 			;						\
335 		else
336 
337 /*
338  * Attributes of the physical system, and the root of the jail tree.
339  */
340 extern struct	prison prison0;
341 
342 TAILQ_HEAD(prisonlist, prison);
343 extern struct	prisonlist allprison;
344 extern struct	sx allprison_lock;
345 
346 /*
347  * Sysctls to describe jail parameters.
348  */
349 SYSCTL_DECL(_security_jail_param);
350 
351 #define	SYSCTL_JAIL_PARAM(module, param, type, fmt, descr)		\
352     SYSCTL_PROC(_security_jail_param ## module, OID_AUTO, param,	\
353 	(type) | CTLFLAG_MPSAFE, NULL, 0, sysctl_jail_param, fmt, descr)
354 #define	SYSCTL_JAIL_PARAM_STRING(module, param, access, len, descr)	\
355     SYSCTL_PROC(_security_jail_param ## module, OID_AUTO, param,	\
356 	CTLTYPE_STRING | CTLFLAG_MPSAFE | (access), NULL, len,		\
357 	sysctl_jail_param, "A", descr)
358 #define	SYSCTL_JAIL_PARAM_STRUCT(module, param, access, len, fmt, descr)\
359     SYSCTL_PROC(_security_jail_param ## module, OID_AUTO, param,	\
360 	CTLTYPE_STRUCT | CTLFLAG_MPSAFE | (access), NULL, len,		\
361 	sysctl_jail_param, fmt, descr)
362 #define	SYSCTL_JAIL_PARAM_NODE(module, descr)				\
363     SYSCTL_NODE(_security_jail_param, OID_AUTO, module, CTLFLAG_MPSAFE,	\
364         0, descr)
365 #define	SYSCTL_JAIL_PARAM_SUBNODE(parent, module, descr)		\
366     SYSCTL_NODE(_security_jail_param_##parent, OID_AUTO, module, 	\
367         CTLFLAG_MPSAFE, 0, descr)
368 #define	SYSCTL_JAIL_PARAM_SYS_NODE(module, access, descr)		\
369     SYSCTL_JAIL_PARAM_NODE(module, descr);				\
370     SYSCTL_JAIL_PARAM(_##module, , CTLTYPE_INT | (access), "E,jailsys",	\
371 	descr)
372 
373 /*
374  * Kernel support functions for jail().
375  */
376 struct ucred;
377 struct mount;
378 struct sockaddr;
379 struct statfs;
380 struct vfsconf;
381 
382 /*
383  * Return 1 if the passed credential is in a jail, otherwise 0.
384  */
385 #define jailed(cred)	(cred->cr_prison != &prison0)
386 
387 int jailed_without_vnet(struct ucred *);
388 void getcredhostname(struct ucred *, char *, size_t);
389 void getcreddomainname(struct ucred *, char *, size_t);
390 void getcredhostuuid(struct ucred *, char *, size_t);
391 void getcredhostid(struct ucred *, unsigned long *);
392 void getjailname(struct ucred *cred, char *name, size_t len);
393 void prison0_init(void);
394 int prison_allow(struct ucred *, unsigned);
395 int prison_check(struct ucred *cred1, struct ucred *cred2);
396 int prison_owns_vnet(struct ucred *);
397 int prison_canseemount(struct ucred *cred, struct mount *mp);
398 void prison_enforce_statfs(struct ucred *cred, struct mount *mp,
399     struct statfs *sp);
400 struct prison *prison_find(int prid);
401 struct prison *prison_find_child(struct prison *, int);
402 struct prison *prison_find_name(struct prison *, const char *);
403 int prison_flag(struct ucred *, unsigned);
404 void prison_free(struct prison *pr);
405 void prison_free_locked(struct prison *pr);
406 void prison_hold(struct prison *pr);
407 void prison_hold_locked(struct prison *pr);
408 void prison_proc_hold(struct prison *);
409 void prison_proc_free(struct prison *);
410 void prison_set_allow(struct ucred *cred, unsigned flag, int enable);
411 int prison_ischild(struct prison *, struct prison *);
412 bool prison_isalive(struct prison *);
413 bool prison_isvalid(struct prison *);
414 int prison_equal_ip4(struct prison *, struct prison *);
415 int prison_get_ip4(struct ucred *cred, struct in_addr *ia);
416 int prison_local_ip4(struct ucred *cred, struct in_addr *ia);
417 int prison_remote_ip4(struct ucred *cred, struct in_addr *ia);
418 int prison_check_ip4(const struct ucred *, const struct in_addr *);
419 int prison_check_ip4_locked(const struct prison *, const struct in_addr *);
420 int prison_saddrsel_ip4(struct ucred *, struct in_addr *);
421 int prison_restrict_ip4(struct prison *, struct in_addr *);
422 int prison_qcmp_v4(const void *, const void *);
423 #ifdef INET6
424 int prison_equal_ip6(struct prison *, struct prison *);
425 int prison_get_ip6(struct ucred *, struct in6_addr *);
426 int prison_local_ip6(struct ucred *, struct in6_addr *, int);
427 int prison_remote_ip6(struct ucred *, struct in6_addr *);
428 int prison_check_ip6(const struct ucred *, const struct in6_addr *);
429 int prison_check_ip6_locked(const struct prison *, const struct in6_addr *);
430 int prison_saddrsel_ip6(struct ucred *, struct in6_addr *);
431 int prison_restrict_ip6(struct prison *, struct in6_addr *);
432 int prison_qcmp_v6(const void *, const void *);
433 #endif
434 int prison_check_af(struct ucred *cred, int af);
435 int prison_if(struct ucred *cred, const struct sockaddr *sa);
436 char *prison_name(struct prison *, struct prison *);
437 int prison_priv_check(struct ucred *cred, int priv);
438 int sysctl_jail_param(SYSCTL_HANDLER_ARGS);
439 unsigned prison_add_allow(const char *prefix, const char *name,
440     const char *prefix_descr, const char *descr);
441 void prison_add_vfs(struct vfsconf *vfsp);
442 void prison_racct_foreach(void (*callback)(struct racct *racct,
443     void *arg2, void *arg3), void (*pre)(void), void (*post)(void),
444     void *arg2, void *arg3);
445 struct prison_racct *prison_racct_find(const char *name);
446 void prison_racct_hold(struct prison_racct *prr);
447 void prison_racct_free(struct prison_racct *prr);
448 
449 #endif /* _KERNEL */
450 #endif /* !_SYS_JAIL_H_ */
451