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/ns_common.h> 7#include <linux/sched.h> 8#include <linux/err.h> 9 10#define UID_GID_MAP_MAX_EXTENTS 5 11 12struct uid_gid_map { /* 64 bytes -- 1 cache line */ 13 u32 nr_extents; 14 struct uid_gid_extent { 15 u32 first; 16 u32 lower_first; 17 u32 count; 18 } extent[UID_GID_MAP_MAX_EXTENTS]; 19}; 20 21#define USERNS_SETGROUPS_ALLOWED 1UL 22 23#define USERNS_INIT_FLAGS USERNS_SETGROUPS_ALLOWED 24 25struct user_namespace { 26 struct uid_gid_map uid_map; 27 struct uid_gid_map gid_map; 28 struct uid_gid_map projid_map; 29 atomic_t count; 30 struct user_namespace *parent; 31 int level; 32 kuid_t owner; 33 kgid_t group; 34 struct ns_common ns; 35 unsigned long flags; 36 37 /* Register of per-UID persistent keyrings for this namespace */ 38#ifdef CONFIG_PERSISTENT_KEYRINGS 39 struct key *persistent_keyring_register; 40 struct rw_semaphore persistent_keyring_register_sem; 41#endif 42}; 43 44extern struct user_namespace init_user_ns; 45 46#ifdef CONFIG_USER_NS 47 48static inline struct user_namespace *get_user_ns(struct user_namespace *ns) 49{ 50 if (ns) 51 atomic_inc(&ns->count); 52 return ns; 53} 54 55extern int create_user_ns(struct cred *new); 56extern int unshare_userns(unsigned long unshare_flags, struct cred **new_cred); 57extern void free_user_ns(struct user_namespace *ns); 58 59static inline void put_user_ns(struct user_namespace *ns) 60{ 61 if (ns && atomic_dec_and_test(&ns->count)) 62 free_user_ns(ns); 63} 64 65struct seq_operations; 66extern const struct seq_operations proc_uid_seq_operations; 67extern const struct seq_operations proc_gid_seq_operations; 68extern const struct seq_operations proc_projid_seq_operations; 69extern ssize_t proc_uid_map_write(struct file *, const char __user *, size_t, loff_t *); 70extern ssize_t proc_gid_map_write(struct file *, const char __user *, size_t, loff_t *); 71extern ssize_t proc_projid_map_write(struct file *, const char __user *, size_t, loff_t *); 72extern ssize_t proc_setgroups_write(struct file *, const char __user *, size_t, loff_t *); 73extern int proc_setgroups_show(struct seq_file *m, void *v); 74extern bool userns_may_setgroups(const struct user_namespace *ns); 75#else 76 77static inline struct user_namespace *get_user_ns(struct user_namespace *ns) 78{ 79 return &init_user_ns; 80} 81 82static inline int create_user_ns(struct cred *new) 83{ 84 return -EINVAL; 85} 86 87static inline int unshare_userns(unsigned long unshare_flags, 88 struct cred **new_cred) 89{ 90 if (unshare_flags & CLONE_NEWUSER) 91 return -EINVAL; 92 return 0; 93} 94 95static inline void put_user_ns(struct user_namespace *ns) 96{ 97} 98 99static inline bool userns_may_setgroups(const struct user_namespace *ns) 100{ 101 return true; 102} 103#endif 104 105#endif /* _LINUX_USER_H */ 106