xref: /xnu-8020.101.4/bsd/sys/persona.h (revision e7776783b89a353188416a9a346c6cdb4928faad)
1 /*
2  * Copyright (c) 2015 Apple Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
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8  * Version 2.0 (the 'License'). You may not use this file except in
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10  * may not be used to create, or enable the creation or redistribution of,
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14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
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27  */
28 #ifndef _SYS_PERSONA_H_
29 #define _SYS_PERSONA_H_
30 
31 #ifdef PRIVATE
32 #include <sys/param.h>
33 
34 #ifdef KERNEL
35 __enum_decl(persona_type_t, int, {
36 #else /* !KERNEL */
37 enum {
38 #endif /* KERNEL */
39 	PERSONA_INVALID      = 0,
40 	PERSONA_GUEST        = 1,
41 	PERSONA_MANAGED      = 2,
42 	PERSONA_PRIV         = 3,
43 	PERSONA_SYSTEM       = 4,
44 	PERSONA_DEFAULT      = 5,
45 	PERSONA_SYSTEM_PROXY = 6,
46 	PERSONA_SYS_EXT      = 7,
47 	PERSONA_ENTERPRISE   = 8,
48 
49 	PERSONA_TYPE_MAX     = PERSONA_ENTERPRISE,
50 #ifdef KERNEL
51 });
52 #else /* !KERNEL */
53 };
54 #endif /* KERNEL */
55 
56 #define PERSONA_ID_NONE ((uid_t)-1)
57 
58 struct kpersona_info {
59 	uint32_t persona_info_version;
60 
61 	uid_t    persona_id; /* overlaps with UID */
62 	int      persona_type;
63 	gid_t    persona_gid;
64 	uint32_t persona_ngroups;
65 	gid_t    persona_groups[NGROUPS];
66 	uid_t    persona_gmuid;
67 	char     persona_name[MAXLOGNAME + 1];
68 
69 	/* TODO: MAC policies?! */
70 };
71 
72 #define PERSONA_INFO_V1       1
73 #define PERSONA_INFO_V1_SIZE  (sizeof(struct kpersona_info))
74 
75 
76 #define PERSONA_OP_ALLOC    1
77 #define PERSONA_OP_PALLOC   2
78 #define PERSONA_OP_DEALLOC  3
79 #define PERSONA_OP_GET      4
80 #define PERSONA_OP_INFO     5
81 #define PERSONA_OP_PIDINFO  6
82 #define PERSONA_OP_FIND     7
83 #define PERSONA_OP_GETPATH  8
84 #define PERSONA_OP_FIND_BY_TYPE  9
85 
86 #define PERSONA_MGMT_ENTITLEMENT "com.apple.private.persona-mgmt"
87 
88 #ifndef KERNEL
89 /*
90  * user space persona interface
91  */
92 
93 /*
94  * kpersona_alloc: Allocate a new in-kernel persona
95  *
96  * Parameters:
97  *       info: Pointer to persona info structure describing the
98  *             attributes of the persona to create / allocate.
99  *
100  *         id: output: set to the ID of the created persona
101  *
102  * Note:
103  *      The 'persona_id' field of the 'info' parameter is ignored.
104  *
105  * Return:
106  *        != 0: ERROR
107  *        == 0: Success
108  */
109 int kpersona_alloc(struct kpersona_info *info, uid_t *id);
110 
111 /*
112  * kpersona_palloc: Allocate a new in-kernel persona with a directory
113  *                 pathname
114  *
115  * Parameters:
116  *       info: Pointer to persona info structure describing the
117  *             attributes of the persona to create / allocate.
118  *
119  *       path: Pointer to directory name that stores persona specific
120  *             data. Assumes path buffer length = MAXPATHLEN and is a
121  *             null-terminated string.
122  *
123  *         id: output: set to the ID of the created persona
124  *
125  * Note:
126  *      The 'persona_id' field of the 'info' parameter is ignored.
127  *
128  * Return:
129  *        != 0: ERROR
130  *        == 0: Success
131  */
132 int kpersona_palloc(struct kpersona_info *info, uid_t *id, char path[MAXPATHLEN]);
133 
134 /*
135  * kpersona_dealloc: delete / destroy an in-kernel persona
136  *
137  * Parameters:
138  *         id: the ID of the persona to destroy
139  *
140  * Return:
141  *        < 0: ERROR
142  *          0: Success
143  */
144 int kpersona_dealloc(uid_t id);
145 
146 /*
147  * kpersona_get: retrieve the persona with which the current thread is running
148  *
149  * To find the proc's persona id use kpersona_pidinfo
150  *
151  * Parameters:
152  *         id: output: will be filled with the persona id from the voucher adopted
153  *             on the current thread. If that voucher contains no persona information
154  *             or there is no such voucher, then it defaults to the proc's persona id.
155  *
156  * Return:
157  *        < 0: Thread is not running under any persona
158  *          0: Success (uuid is filled with running persona UUID)
159  */
160 int kpersona_get(uid_t *id);
161 
162 /*
163  * kpersona_get_path: retrieve the given persona's path
164  *
165  * Parameters:
166  *         id: ID of the persona
167  *
168  *         path: output: filled in with path on success.
169  *               Assumes path buffer length = MAXPATHLEN
170  *
171  * Return:
172  *        < 0: Error
173  *          0: Success
174  */
175 int kpersona_getpath(uid_t id, char path[MAXPATHLEN]);
176 
177 /*
178  * kpersona_info: gather info about the given persona
179  *
180  * Parameters:
181  *         id: ID of the persona to investigate
182  *             If set to 0, it uses persona id from the voucher adopted on the current
183  *             thread. If that voucher contains no persona information or there is no
184  *             such voucher, then it defaults to the proc's persona id.
185  *
186  *       info: output: filled in with persona attributes on success.
187  *
188  * Return:
189  *        < 0: ERROR
190  *          0: Success
191  */
192 int kpersona_info(uid_t id, struct kpersona_info *info);
193 
194 /*
195  * kpersona_pidinfo: gather persona info about the given PID
196  *
197  * Parameters:
198  *        pid: PID of the process whose persona info we're to return
199  *
200  *       info: output: filled in with persona attributes on success.
201  *
202  * Return:
203  *        < 0: ERROR
204  *          0: Success
205  */
206 int kpersona_pidinfo(pid_t pid, struct kpersona_info *info);
207 
208 /*
209  * kpersona_find: lookup the kernel's UUID of a persona
210  *
211  * Parameters:
212  *       name: Local login name of the persona.
213  *             Set this to NULL to find personas by 'uid'.
214  *
215  *        uid: UID of the persona.
216  *             Set this to -1 to find personas by 'name'
217  *
218  *         id: output: the ID(s) matching the input parameters
219  *             This can be NULL
220  *
221  *      idlen: input - size of 'id' buffer (in number of IDs)
222  *             output - the total required size of the 'id' buffer
223  *                      (in number of IDs) - may be larger than input size
224  * Note:
225  *      At least one of 'name' or 'uid' must be set.
226  *
227  * Return:
228  *         < 0: ERROR
229  *        >= 0: The number of IDs found to match the input parameters
230  */
231 int kpersona_find(const char *name, uid_t uid, uid_t *id, size_t *idlen);
232 
233 /*
234  * kpersona_find_by_type: lookup the persona ids by type
235  *
236  * Parameters:
237  *  persona_type: Type of persona id (see enum)
238  *
239  *           id: output: the ID(s) matching the input parameters
240  *               This can be NULL
241  *
242  *        idlen: input - size of 'id' buffer (in number of IDs)
243  *               output - the total required size of the 'id' buffer
244  *                      (in number of IDs) - may be larger than input size
245  * Return:
246  *         < 0: ERROR
247  *        >= 0: The number of IDs found to match the input parameters
248  */
249 int kpersona_find_by_type(int persona_type, uid_t *id, size_t *idlen);
250 #endif /* !KERNEL */
251 
252 #ifdef KERNEL_PRIVATE
253 /* XNU + kext private interface */
254 #include <sys/cdefs.h>
255 #include <sys/kauth.h>
256 #include <libkern/libkern.h>
257 #include <os/refcnt.h>
258 
259 #ifdef PERSONA_DEBUG
260 #include <os/log.h>
261 #define persona_dbg(fmt, ...) \
262 	os_log(OS_LOG_DEFAULT, "[%4d] %s:  " fmt "\n", \
263 	       current_proc() ? proc_getpid(current_proc()) : -1, \
264 	       __func__, ## __VA_ARGS__)
265 #else
266 #define persona_dbg(fmt, ...) do { } while (0)
267 #endif
268 
269 /*
270  * Persona
271  */
272 #ifdef XNU_KERNEL_PRIVATE
273 /* only XNU proper needs to see the persona structure */
274 struct persona {
275 	os_refcnt_t  pna_refcount;
276 	int32_t      pna_valid;
277 
278 	uid_t        pna_id;
279 	persona_type_t pna_type;
280 	char         pna_login[MAXLOGNAME + 1];
281 	char         *pna_path;
282 
283 	kauth_cred_t XNU_PTRAUTH_SIGNED_PTR("persona.pna_cred") pna_cred;
284 	uid_t        pna_pgid;
285 
286 	int          pna_cred_locked; /* set upon first adoption */
287 
288 	LIST_ENTRY(persona) pna_list;
289 
290 	/* this could go away if we used a coalition */
291 	LIST_HEAD(, proc)   pna_members;
292 
293 	lck_mtx_t    pna_lock;
294 
295 	/*
296 	 * We can add things here such as PID maps, UID maps, etc.
297 	 */
298 #ifdef PERSONA_DEBUG
299 	char         pna_desc[128];
300 #endif
301 };
302 
303 #define persona_lock(persona)     lck_mtx_lock(&(persona)->pna_lock)
304 #define persona_unlock(persona)   lck_mtx_unlock(&(persona)->pna_lock)
305 #define persona_try_lock(persona) lck_mtx_try_lock(&(persona)->pna_lock)
306 
307 #define persona_lock_assert_held(persona) \
308 	LCK_MTX_ASSERT(&(persona)->pna_lock, LCK_MTX_ASSERT_OWNED)
309 
310 #ifdef PERSONA_DEBUG
311 static inline const char *
persona_desc(struct persona * persona,int locked)312 persona_desc(struct persona *persona, int locked)
313 {
314 	if (!persona) {
315 		return "<none>";
316 	}
317 
318 	if (persona->pna_desc[0] != 0) {
319 		return persona->pna_desc;
320 	}
321 
322 	if (!locked) {
323 		persona_lock(persona);
324 	}
325 	if (persona->pna_desc[0] != 0) {
326 		goto out_unlock;
327 	}
328 
329 	char *p = &persona->pna_desc[0];
330 	char *end = p + sizeof(persona->pna_desc) - 1;
331 
332 	*end = 0;
333 	p += scnprintf(p, end - p, "%s/%d:%d",
334 	    persona->pna_login,
335 	    kauth_cred_getuid(persona->pna_cred),
336 	    kauth_cred_getgid(persona->pna_cred));
337 
338 	if (p <= end) {
339 		*p = 0;
340 	}
341 out_unlock:
342 	if (!locked) {
343 		persona_unlock(persona);
344 	}
345 
346 	return persona->pna_desc;
347 }
348 #else /* !PERSONA_DEBUG */
349 static inline const char *
persona_desc(struct persona * persona,int locked)350 persona_desc(struct persona *persona, int locked)
351 {
352 	(void)persona;
353 	(void)locked;
354 	return "<persona>";
355 }
356 #endif
357 
358 #else /* !XNU_KERNEL_PRIVATE */
359 /* kexts should only see an opaque persona structure */
360 struct persona;
361 #endif
362 
363 __BEGIN_DECLS
364 
365 #ifndef _KAUTH_CRED_T
366 #define _KAUTH_CRED_T
367 typedef struct ucred *kauth_cred_t;
368 #endif  /* !_KAUTH_CRED_T */
369 
370 /* returns the persona ID for the given pesona structure */
371 uid_t persona_get_id(struct persona *persona);
372 
373 /* returns the type of the persona (see enum above: PERSONA_GUEST, etc.) */
374 int persona_get_type(struct persona *persona);
375 
376 /* returns ref on kauth_cred_t that must be dropped via kauth_cred_unref() */
377 kauth_cred_t persona_get_cred(struct persona *persona);
378 
379 /* returns a reference that must be released with persona_put() */
380 struct persona *persona_lookup(uid_t id);
381 
382 /*
383  * Search for personas based on name or uid
384  *
385  * Parameters:
386  *       name: Local login name of the persona.
387  *             Set this to NULL to find personas by 'uid'.
388  *
389  *        uid: UID of the persona.
390  *             Set this to -1 to find personas by 'name'
391  *
392  *    persona: output - array of persona pointers. Each non-NULL value
393  *             must* be released with persona_put. This can be NULL.
394  *
395  *       plen: input - size of 'persona' buffer (in number of pointers)
396  *             output - the total required size of the 'persona' buffer (could be larger than input value)
397  *
398  * Return:
399  *           0: Success
400  *        != 0: failure (BSD errno value ESRCH or EINVAL)
401  */
402 int persona_find(const char *login, uid_t uid,
403     struct persona **persona, size_t *plen);
404 
405 /* returns a reference that must be released with persona_put() */
406 struct persona *persona_proc_get(pid_t pid);
407 
408 /* returns the persona id tied to the current thread (also uses adopted voucher) */
409 uid_t current_persona_get_id(void);
410 
411 /* returns a reference to the persona tied to the current thread (also uses adopted voucher) */
412 struct persona *current_persona_get(void);
413 
414 /* get a reference to a persona structure */
415 struct persona *persona_get(struct persona *persona);
416 
417 /* release a reference to a persona structure */
418 void persona_put(struct persona *persona);
419 
420 /*
421  * Search for personas of a given type, 'persona_type'.
422  *
423  * Parameters:
424  *   persona_type: Type of persona (see enum)
425  *
426  *        persona: output - array of persona pointers. Each non-NULL value
427  *        must* be released with persona_put. This can be NULL.
428  *
429  *           plen: input - size of 'persona' buffer (in number of pointers)
430  *                 output - the total required size of the 'persona' buffer (could be larger than input value)
431  *
432  * Return:
433  *           0: Success
434  *        != 0: failure (BSD errno value ESRCH or EINVAL)
435  */
436 int persona_find_by_type(persona_type_t persona_type, struct persona **persona,
437     size_t *plen);
438 
439 #ifdef XNU_KERNEL_PRIVATE
440 
441 #if CONFIG_PERSONAS
442 #include <sys/proc_internal.h>
443 
444 /*
445  * In-kernel persona API
446  */
447 extern const uint32_t g_max_personas;
448 
449 struct persona *persona_alloc(uid_t id, const char *login,
450     persona_type_t type, char *path, int *error);
451 
452 int persona_init_begin(struct persona *persona);
453 void persona_init_end(struct persona *persona, int error);
454 
455 struct persona *persona_lookup_and_invalidate(uid_t id);
456 int persona_verify_and_set_uniqueness(struct persona *persona);
457 boolean_t persona_is_unique(struct persona *persona);
458 
459 static inline int
proc_has_persona(proc_t p)460 proc_has_persona(proc_t p)
461 {
462 	if (p && p->p_persona) {
463 		return 1;
464 	}
465 	return 0;
466 }
467 
468 static inline uid_t
persona_id_from_proc(proc_t p)469 persona_id_from_proc(proc_t p)
470 {
471 	if (p && p->p_persona) {
472 		return p->p_persona->pna_id;
473 	}
474 	return PERSONA_ID_NONE;
475 }
476 
477 int persona_proc_inherit(proc_t child, proc_t parent);
478 
479 int persona_proc_adopt_id(proc_t p, uid_t id,
480     kauth_cred_t auth_override);
481 int persona_proc_adopt(proc_t p, struct persona *persona,
482     kauth_cred_t auth_override);
483 int persona_proc_drop(proc_t p);
484 
485 int persona_set_cred(struct persona *persona, kauth_cred_t cred);
486 int persona_set_cred_from_proc(struct persona *persona, proc_t proc);
487 
488 uid_t persona_get_uid(struct persona *persona);
489 
490 int persona_set_gid(struct persona *persona, gid_t gid);
491 gid_t persona_get_gid(struct persona *persona);
492 
493 int persona_set_groups(struct persona *persona, gid_t *groups, size_t ngroups, uid_t gmuid);
494 int persona_get_groups(struct persona *persona, size_t *ngroups, gid_t *groups, size_t groups_sz);
495 
496 uid_t persona_get_gmuid(struct persona *persona);
497 
498 int persona_get_login(struct persona *persona, char login[MAXLOGNAME + 1]);
499 
500 /* returns a reference that must be released with persona_put() */
501 struct persona *persona_proc_get(pid_t pid);
502 
503 int persona_find_all(const char *login, uid_t uid, persona_type_t persona_type,
504     struct persona **persona, size_t *plen);
505 
506 #else /* !CONFIG_PERSONAS */
507 
508 static inline int
proc_has_persona(__unused proc_t p)509 proc_has_persona(__unused proc_t p)
510 {
511 	return 0;
512 }
513 
514 static inline uid_t
persona_id_from_proc(__unused proc_t p)515 persona_id_from_proc(__unused proc_t p)
516 {
517 	return PERSONA_ID_NONE;
518 }
519 
520 #endif /* CONFIG_PERSONAS */
521 #endif /* XNU_KERNEL_PRIVATE */
522 __END_DECLS
523 
524 #endif /* KERNEL_PRIVATE */
525 
526 #endif /* PRIVATE */
527 #endif /* _SYS_PERSONA_H_ */
528