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8#ifndef _LINUX_CRED_H
9#define _LINUX_CRED_H
10
11#include <linux/capability.h>
12#include <linux/init.h>
13#include <linux/key.h>
14#include <linux/atomic.h>
15#include <linux/uidgid.h>
16#include <linux/sched.h>
17#include <linux/sched/user.h>
18
19struct cred;
20struct inode;
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25struct group_info {
26 atomic_t usage;
27 int ngroups;
28 kgid_t gid[0];
29} __randomize_layout;
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40static inline struct group_info *get_group_info(struct group_info *gi)
41{
42 atomic_inc(&gi->usage);
43 return gi;
44}
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49
50#define put_group_info(group_info) \
51do { \
52 if (atomic_dec_and_test(&(group_info)->usage)) \
53 groups_free(group_info); \
54} while (0)
55
56extern struct group_info init_groups;
57#ifdef CONFIG_MULTIUSER
58extern struct group_info *groups_alloc(int);
59extern void groups_free(struct group_info *);
60
61extern int in_group_p(kgid_t);
62extern int in_egroup_p(kgid_t);
63extern int groups_search(const struct group_info *, kgid_t);
64
65extern int set_current_groups(struct group_info *);
66extern void set_groups(struct cred *, struct group_info *);
67extern bool may_setgroups(void);
68extern void groups_sort(struct group_info *);
69#else
70static inline void groups_free(struct group_info *group_info)
71{
72}
73
74static inline int in_group_p(kgid_t grp)
75{
76 return 1;
77}
78static inline int in_egroup_p(kgid_t grp)
79{
80 return 1;
81}
82static inline int groups_search(const struct group_info *group_info, kgid_t grp)
83{
84 return 1;
85}
86#endif
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111struct cred {
112 atomic_t usage;
113#ifdef CONFIG_DEBUG_CREDENTIALS
114 atomic_t subscribers;
115 void *put_addr;
116 unsigned magic;
117#define CRED_MAGIC 0x43736564
118#define CRED_MAGIC_DEAD 0x44656144
119#endif
120 kuid_t uid;
121 kgid_t gid;
122 kuid_t suid;
123 kgid_t sgid;
124 kuid_t euid;
125 kgid_t egid;
126 kuid_t fsuid;
127 kgid_t fsgid;
128 unsigned securebits;
129 kernel_cap_t cap_inheritable;
130 kernel_cap_t cap_permitted;
131 kernel_cap_t cap_effective;
132 kernel_cap_t cap_bset;
133 kernel_cap_t cap_ambient;
134#ifdef CONFIG_KEYS
135 unsigned char jit_keyring;
136
137 struct key *session_keyring;
138 struct key *process_keyring;
139 struct key *thread_keyring;
140 struct key *request_key_auth;
141#endif
142#ifdef CONFIG_SECURITY
143 void *security;
144#endif
145 struct user_struct *user;
146 struct user_namespace *user_ns;
147 struct group_info *group_info;
148
149 union {
150 int non_rcu;
151 struct rcu_head rcu;
152 };
153} __randomize_layout;
154
155extern void __put_cred(struct cred *);
156extern void exit_creds(struct task_struct *);
157extern int copy_creds(struct task_struct *, unsigned long);
158extern const struct cred *get_task_cred(struct task_struct *);
159extern struct cred *cred_alloc_blank(void);
160extern struct cred *prepare_creds(void);
161extern struct cred *prepare_exec_creds(void);
162extern int commit_creds(struct cred *);
163extern void abort_creds(struct cred *);
164extern const struct cred *override_creds(const struct cred *);
165extern void revert_creds(const struct cred *);
166extern struct cred *prepare_kernel_cred(struct task_struct *);
167extern int change_create_files_as(struct cred *, struct inode *);
168extern int set_security_override(struct cred *, u32);
169extern int set_security_override_from_ctx(struct cred *, const char *);
170extern int set_create_files_as(struct cred *, struct inode *);
171extern int cred_fscmp(const struct cred *, const struct cred *);
172extern void __init cred_init(void);
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176
177#ifdef CONFIG_DEBUG_CREDENTIALS
178extern void __invalid_creds(const struct cred *, const char *, unsigned);
179extern void __validate_process_creds(struct task_struct *,
180 const char *, unsigned);
181
182extern bool creds_are_invalid(const struct cred *cred);
183
184static inline void __validate_creds(const struct cred *cred,
185 const char *file, unsigned line)
186{
187 if (unlikely(creds_are_invalid(cred)))
188 __invalid_creds(cred, file, line);
189}
190
191#define validate_creds(cred) \
192do { \
193 __validate_creds((cred), __FILE__, __LINE__); \
194} while(0)
195
196#define validate_process_creds() \
197do { \
198 __validate_process_creds(current, __FILE__, __LINE__); \
199} while(0)
200
201extern void validate_creds_for_do_exit(struct task_struct *);
202#else
203static inline void validate_creds(const struct cred *cred)
204{
205}
206static inline void validate_creds_for_do_exit(struct task_struct *tsk)
207{
208}
209static inline void validate_process_creds(void)
210{
211}
212#endif
213
214static inline bool cap_ambient_invariant_ok(const struct cred *cred)
215{
216 return cap_issubset(cred->cap_ambient,
217 cap_intersect(cred->cap_permitted,
218 cred->cap_inheritable));
219}
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228static inline struct cred *get_new_cred(struct cred *cred)
229{
230 atomic_inc(&cred->usage);
231 return cred;
232}
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247static inline const struct cred *get_cred(const struct cred *cred)
248{
249 struct cred *nonconst_cred = (struct cred *) cred;
250 if (!cred)
251 return cred;
252 validate_creds(cred);
253 nonconst_cred->non_rcu = 0;
254 return get_new_cred(nonconst_cred);
255}
256
257static inline const struct cred *get_cred_rcu(const struct cred *cred)
258{
259 struct cred *nonconst_cred = (struct cred *) cred;
260 if (!cred)
261 return NULL;
262 if (!atomic_inc_not_zero(&nonconst_cred->usage))
263 return NULL;
264 validate_creds(cred);
265 nonconst_cred->non_rcu = 0;
266 return cred;
267}
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280static inline void put_cred(const struct cred *_cred)
281{
282 struct cred *cred = (struct cred *) _cred;
283
284 if (cred) {
285 validate_creds(cred);
286 if (atomic_dec_and_test(&(cred)->usage))
287 __put_cred(cred);
288 }
289}
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297#define current_cred() \
298 rcu_dereference_protected(current->cred, 1)
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306#define current_real_cred() \
307 rcu_dereference_protected(current->real_cred, 1)
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319#define __task_cred(task) \
320 rcu_dereference((task)->real_cred)
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329#define get_current_cred() \
330 (get_cred(current_cred()))
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338#define get_current_user() \
339({ \
340 struct user_struct *__u; \
341 const struct cred *__cred; \
342 __cred = current_cred(); \
343 __u = get_uid(__cred->user); \
344 __u; \
345})
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353#define get_current_groups() \
354({ \
355 struct group_info *__groups; \
356 const struct cred *__cred; \
357 __cred = current_cred(); \
358 __groups = get_group_info(__cred->group_info); \
359 __groups; \
360})
361
362#define task_cred_xxx(task, xxx) \
363({ \
364 __typeof__(((struct cred *)NULL)->xxx) ___val; \
365 rcu_read_lock(); \
366 ___val = __task_cred((task))->xxx; \
367 rcu_read_unlock(); \
368 ___val; \
369})
370
371#define task_uid(task) (task_cred_xxx((task), uid))
372#define task_euid(task) (task_cred_xxx((task), euid))
373
374#define current_cred_xxx(xxx) \
375({ \
376 current_cred()->xxx; \
377})
378
379#define current_uid() (current_cred_xxx(uid))
380#define current_gid() (current_cred_xxx(gid))
381#define current_euid() (current_cred_xxx(euid))
382#define current_egid() (current_cred_xxx(egid))
383#define current_suid() (current_cred_xxx(suid))
384#define current_sgid() (current_cred_xxx(sgid))
385#define current_fsuid() (current_cred_xxx(fsuid))
386#define current_fsgid() (current_cred_xxx(fsgid))
387#define current_cap() (current_cred_xxx(cap_effective))
388#define current_user() (current_cred_xxx(user))
389
390extern struct user_namespace init_user_ns;
391#ifdef CONFIG_USER_NS
392#define current_user_ns() (current_cred_xxx(user_ns))
393#else
394static inline struct user_namespace *current_user_ns(void)
395{
396 return &init_user_ns;
397}
398#endif
399
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401#define current_uid_gid(_uid, _gid) \
402do { \
403 const struct cred *__cred; \
404 __cred = current_cred(); \
405 *(_uid) = __cred->uid; \
406 *(_gid) = __cred->gid; \
407} while(0)
408
409#define current_euid_egid(_euid, _egid) \
410do { \
411 const struct cred *__cred; \
412 __cred = current_cred(); \
413 *(_euid) = __cred->euid; \
414 *(_egid) = __cred->egid; \
415} while(0)
416
417#define current_fsuid_fsgid(_fsuid, _fsgid) \
418do { \
419 const struct cred *__cred; \
420 __cred = current_cred(); \
421 *(_fsuid) = __cred->fsuid; \
422 *(_fsgid) = __cred->fsgid; \
423} while(0)
424
425#endif
426