Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1#ifndef _LINUX_USER_NAMESPACE_H
2#define _LINUX_USER_NAMESPACE_H
3
4#include <linux/kref.h>
5#include <linux/nsproxy.h>
6#include <linux/sched.h>
7#include <linux/err.h>
8
9#define UID_GID_MAP_MAX_EXTENTS 5
10
11struct uid_gid_map { /* 64 bytes -- 1 cache line */
12 u32 nr_extents;
13 struct uid_gid_extent {
14 u32 first;
15 u32 lower_first;
16 u32 count;
17 } extent[UID_GID_MAP_MAX_EXTENTS];
18};
19
20struct user_namespace {
21 struct uid_gid_map uid_map;
22 struct uid_gid_map gid_map;
23 struct uid_gid_map projid_map;
24 atomic_t count;
25 struct user_namespace *parent;
26 int level;
27 kuid_t owner;
28 kgid_t group;
29 unsigned int proc_inum;
30
31 /* Register of per-UID persistent keyrings for this namespace */
32#ifdef CONFIG_PERSISTENT_KEYRINGS
33 struct key *persistent_keyring_register;
34 struct rw_semaphore persistent_keyring_register_sem;
35#endif
36};
37
38extern struct user_namespace init_user_ns;
39
40#ifdef CONFIG_USER_NS
41
42static inline struct user_namespace *get_user_ns(struct user_namespace *ns)
43{
44 if (ns)
45 atomic_inc(&ns->count);
46 return ns;
47}
48
49extern int create_user_ns(struct cred *new);
50extern int unshare_userns(unsigned long unshare_flags, struct cred **new_cred);
51extern void free_user_ns(struct user_namespace *ns);
52
53static inline void put_user_ns(struct user_namespace *ns)
54{
55 if (ns && atomic_dec_and_test(&ns->count))
56 free_user_ns(ns);
57}
58
59struct seq_operations;
60extern struct seq_operations proc_uid_seq_operations;
61extern struct seq_operations proc_gid_seq_operations;
62extern struct seq_operations proc_projid_seq_operations;
63extern ssize_t proc_uid_map_write(struct file *, const char __user *, size_t, loff_t *);
64extern ssize_t proc_gid_map_write(struct file *, const char __user *, size_t, loff_t *);
65extern ssize_t proc_projid_map_write(struct file *, const char __user *, size_t, loff_t *);
66#else
67
68static inline struct user_namespace *get_user_ns(struct user_namespace *ns)
69{
70 return &init_user_ns;
71}
72
73static inline int create_user_ns(struct cred *new)
74{
75 return -EINVAL;
76}
77
78static inline int unshare_userns(unsigned long unshare_flags,
79 struct cred **new_cred)
80{
81 if (unshare_flags & CLONE_NEWUSER)
82 return -EINVAL;
83 return 0;
84}
85
86static inline void put_user_ns(struct user_namespace *ns)
87{
88}
89
90#endif
91
92#endif /* _LINUX_USER_H */