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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 struct rcu_head rcu;
149} __randomize_layout;
150
151extern void __put_cred(struct cred *);
152extern void exit_creds(struct task_struct *);
153extern int copy_creds(struct task_struct *, unsigned long);
154extern const struct cred *get_task_cred(struct task_struct *);
155extern struct cred *cred_alloc_blank(void);
156extern struct cred *prepare_creds(void);
157extern struct cred *prepare_exec_creds(void);
158extern int commit_creds(struct cred *);
159extern void abort_creds(struct cred *);
160extern const struct cred *override_creds(const struct cred *);
161extern void revert_creds(const struct cred *);
162extern struct cred *prepare_kernel_cred(struct task_struct *);
163extern int change_create_files_as(struct cred *, struct inode *);
164extern int set_security_override(struct cred *, u32);
165extern int set_security_override_from_ctx(struct cred *, const char *);
166extern int set_create_files_as(struct cred *, struct inode *);
167extern int cred_fscmp(const struct cred *, const struct cred *);
168extern void __init cred_init(void);
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172
173#ifdef CONFIG_DEBUG_CREDENTIALS
174extern void __invalid_creds(const struct cred *, const char *, unsigned);
175extern void __validate_process_creds(struct task_struct *,
176 const char *, unsigned);
177
178extern bool creds_are_invalid(const struct cred *cred);
179
180static inline void __validate_creds(const struct cred *cred,
181 const char *file, unsigned line)
182{
183 if (unlikely(creds_are_invalid(cred)))
184 __invalid_creds(cred, file, line);
185}
186
187#define validate_creds(cred) \
188do { \
189 __validate_creds((cred), __FILE__, __LINE__); \
190} while(0)
191
192#define validate_process_creds() \
193do { \
194 __validate_process_creds(current, __FILE__, __LINE__); \
195} while(0)
196
197extern void validate_creds_for_do_exit(struct task_struct *);
198#else
199static inline void validate_creds(const struct cred *cred)
200{
201}
202static inline void validate_creds_for_do_exit(struct task_struct *tsk)
203{
204}
205static inline void validate_process_creds(void)
206{
207}
208#endif
209
210static inline bool cap_ambient_invariant_ok(const struct cred *cred)
211{
212 return cap_issubset(cred->cap_ambient,
213 cap_intersect(cred->cap_permitted,
214 cred->cap_inheritable));
215}
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224static inline struct cred *get_new_cred(struct cred *cred)
225{
226 atomic_inc(&cred->usage);
227 return cred;
228}
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243static inline const struct cred *get_cred(const struct cred *cred)
244{
245 struct cred *nonconst_cred = (struct cred *) cred;
246 if (!cred)
247 return cred;
248 validate_creds(cred);
249 return get_new_cred(nonconst_cred);
250}
251
252static inline const struct cred *get_cred_rcu(const struct cred *cred)
253{
254 struct cred *nonconst_cred = (struct cred *) cred;
255 if (!cred)
256 return NULL;
257 if (!atomic_inc_not_zero(&nonconst_cred->usage))
258 return NULL;
259 validate_creds(cred);
260 return cred;
261}
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274static inline void put_cred(const struct cred *_cred)
275{
276 struct cred *cred = (struct cred *) _cred;
277
278 if (cred) {
279 validate_creds(cred);
280 if (atomic_dec_and_test(&(cred)->usage))
281 __put_cred(cred);
282 }
283}
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291#define current_cred() \
292 rcu_dereference_protected(current->cred, 1)
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300#define current_real_cred() \
301 rcu_dereference_protected(current->real_cred, 1)
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313#define __task_cred(task) \
314 rcu_dereference((task)->real_cred)
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323#define get_current_cred() \
324 (get_cred(current_cred()))
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332#define get_current_user() \
333({ \
334 struct user_struct *__u; \
335 const struct cred *__cred; \
336 __cred = current_cred(); \
337 __u = get_uid(__cred->user); \
338 __u; \
339})
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347#define get_current_groups() \
348({ \
349 struct group_info *__groups; \
350 const struct cred *__cred; \
351 __cred = current_cred(); \
352 __groups = get_group_info(__cred->group_info); \
353 __groups; \
354})
355
356#define task_cred_xxx(task, xxx) \
357({ \
358 __typeof__(((struct cred *)NULL)->xxx) ___val; \
359 rcu_read_lock(); \
360 ___val = __task_cred((task))->xxx; \
361 rcu_read_unlock(); \
362 ___val; \
363})
364
365#define task_uid(task) (task_cred_xxx((task), uid))
366#define task_euid(task) (task_cred_xxx((task), euid))
367
368#define current_cred_xxx(xxx) \
369({ \
370 current_cred()->xxx; \
371})
372
373#define current_uid() (current_cred_xxx(uid))
374#define current_gid() (current_cred_xxx(gid))
375#define current_euid() (current_cred_xxx(euid))
376#define current_egid() (current_cred_xxx(egid))
377#define current_suid() (current_cred_xxx(suid))
378#define current_sgid() (current_cred_xxx(sgid))
379#define current_fsuid() (current_cred_xxx(fsuid))
380#define current_fsgid() (current_cred_xxx(fsgid))
381#define current_cap() (current_cred_xxx(cap_effective))
382#define current_user() (current_cred_xxx(user))
383#define current_security() (current_cred_xxx(security))
384
385extern struct user_namespace init_user_ns;
386#ifdef CONFIG_USER_NS
387#define current_user_ns() (current_cred_xxx(user_ns))
388#else
389static inline struct user_namespace *current_user_ns(void)
390{
391 return &init_user_ns;
392}
393#endif
394
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396#define current_uid_gid(_uid, _gid) \
397do { \
398 const struct cred *__cred; \
399 __cred = current_cred(); \
400 *(_uid) = __cred->uid; \
401 *(_gid) = __cred->gid; \
402} while(0)
403
404#define current_euid_egid(_euid, _egid) \
405do { \
406 const struct cred *__cred; \
407 __cred = current_cred(); \
408 *(_euid) = __cred->euid; \
409 *(_egid) = __cred->egid; \
410} while(0)
411
412#define current_fsuid_fsgid(_fsuid, _fsgid) \
413do { \
414 const struct cred *__cred; \
415 __cred = current_cred(); \
416 *(_fsuid) = __cred->fsuid; \
417 *(_fsgid) = __cred->fsgid; \
418} while(0)
419
420#endif
421