Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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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
32extern struct user_namespace init_user_ns;
33
34#ifdef CONFIG_USER_NS
35
36static inline struct user_namespace *get_user_ns(struct user_namespace *ns)
37{
38 if (ns)
39 atomic_inc(&ns->count);
40 return ns;
41}
42
43extern int create_user_ns(struct cred *new);
44extern int unshare_userns(unsigned long unshare_flags, struct cred **new_cred);
45extern void free_user_ns(struct user_namespace *ns);
46
47static inline void put_user_ns(struct user_namespace *ns)
48{
49 if (ns && atomic_dec_and_test(&ns->count))
50 free_user_ns(ns);
51}
52
53struct seq_operations;
54extern struct seq_operations proc_uid_seq_operations;
55extern struct seq_operations proc_gid_seq_operations;
56extern struct seq_operations proc_projid_seq_operations;
57extern ssize_t proc_uid_map_write(struct file *, const char __user *, size_t, loff_t *);
58extern ssize_t proc_gid_map_write(struct file *, const char __user *, size_t, loff_t *);
59extern ssize_t proc_projid_map_write(struct file *, const char __user *, size_t, loff_t *);
60#else
61
62static inline struct user_namespace *get_user_ns(struct user_namespace *ns)
63{
64 return &init_user_ns;
65}
66
67static inline int create_user_ns(struct cred *new)
68{
69 return -EINVAL;
70}
71
72static inline int unshare_userns(unsigned long unshare_flags,
73 struct cred **new_cred)
74{
75 if (unshare_flags & CLONE_NEWUSER)
76 return -EINVAL;
77 return 0;
78}
79
80static inline void put_user_ns(struct user_namespace *ns)
81{
82}
83
84#endif
85
86#endif /* _LINUX_USER_H */