[mirror_ubuntu-artful-kernel.git] / include / linux / user_namespace.h

#ifndef _LINUX_USER_NAMESPACE_H
#define _LINUX_USER_NAMESPACE_H

#include <linux/kref.h>
#include <linux/nsproxy.h>
#include <linux/ns_common.h>
#include <linux/sched.h>
#include <linux/workqueue.h>
#include <linux/rwsem.h>
#include <linux/sysctl.h>
#include <linux/err.h>

#define UID_GID_MAP_MAX_EXTENTS 5

struct uid_gid_map {	/* 64 bytes -- 1 cache line */
	u32 nr_extents;
	struct uid_gid_extent {
		u32 first;
		u32 lower_first;
		u32 count;
	} extent[UID_GID_MAP_MAX_EXTENTS];
};

#define USERNS_SETGROUPS_ALLOWED 1UL

#define USERNS_INIT_FLAGS USERNS_SETGROUPS_ALLOWED

struct ucounts;

enum ucount_type {
	UCOUNT_USER_NAMESPACES,
	UCOUNT_PID_NAMESPACES,
	UCOUNT_UTS_NAMESPACES,
	UCOUNT_IPC_NAMESPACES,
	UCOUNT_NET_NAMESPACES,
	UCOUNT_MNT_NAMESPACES,
	UCOUNT_CGROUP_NAMESPACES,
#ifdef CONFIG_INOTIFY_USER
	UCOUNT_INOTIFY_INSTANCES,
	UCOUNT_INOTIFY_WATCHES,
#endif
	UCOUNT_COUNTS,
};

struct user_namespace {
	struct uid_gid_map	uid_map;
	struct uid_gid_map	gid_map;
	struct uid_gid_map	projid_map;
	atomic_t		count;
	struct user_namespace	*parent;
	int			level;
	kuid_t			owner;
	kgid_t			group;
	struct ns_common	ns;
	unsigned long		flags;

	/* Register of per-UID persistent keyrings for this namespace */
#ifdef CONFIG_PERSISTENT_KEYRINGS
	struct key		*persistent_keyring_register;
	struct rw_semaphore	persistent_keyring_register_sem;
#endif
	struct work_struct	work;
#ifdef CONFIG_SYSCTL
	struct ctl_table_set	set;
	struct ctl_table_header *sysctls;
#endif
	struct ucounts		*ucounts;
	int ucount_max[UCOUNT_COUNTS];
} __randomize_layout;

struct ucounts {
	struct hlist_node node;
	struct user_namespace *ns;
	kuid_t uid;
	int count;
	atomic_t ucount[UCOUNT_COUNTS];
};

extern struct user_namespace init_user_ns;

bool setup_userns_sysctls(struct user_namespace *ns);
void retire_userns_sysctls(struct user_namespace *ns);
struct ucounts *inc_ucount(struct user_namespace *ns, kuid_t uid, enum ucount_type type);
void dec_ucount(struct ucounts *ucounts, enum ucount_type type);

#ifdef CONFIG_USER_NS

static inline struct user_namespace *get_user_ns(struct user_namespace *ns)
{
	if (ns)
		atomic_inc(&ns->count);
	return ns;
}

extern int create_user_ns(struct cred *new);
extern int unshare_userns(unsigned long unshare_flags, struct cred **new_cred);
extern void __put_user_ns(struct user_namespace *ns);

static inline void put_user_ns(struct user_namespace *ns)
{
	if (ns && atomic_dec_and_test(&ns->count))
		__put_user_ns(ns);
}

struct seq_operations;
extern const struct seq_operations proc_uid_seq_operations;
extern const struct seq_operations proc_gid_seq_operations;
extern const struct seq_operations proc_projid_seq_operations;
extern ssize_t proc_uid_map_write(struct file *, const char __user *, size_t, loff_t *);
extern ssize_t proc_gid_map_write(struct file *, const char __user *, size_t, loff_t *);
extern ssize_t proc_projid_map_write(struct file *, const char __user *, size_t, loff_t *);
extern ssize_t proc_setgroups_write(struct file *, const char __user *, size_t, loff_t *);
extern int proc_setgroups_show(struct seq_file *m, void *v);
extern bool userns_may_setgroups(const struct user_namespace *ns);
extern bool current_in_userns(const struct user_namespace *target_ns);

struct ns_common *ns_get_owner(struct ns_common *ns);
#else

static inline struct user_namespace *get_user_ns(struct user_namespace *ns)
{
	return &init_user_ns;
}

static inline int create_user_ns(struct cred *new)
{
	return -EINVAL;
}

static inline int unshare_userns(unsigned long unshare_flags,
				 struct cred **new_cred)
{
	if (unshare_flags & CLONE_NEWUSER)
		return -EINVAL;
	return 0;
}

static inline void put_user_ns(struct user_namespace *ns)
{
}

static inline bool userns_may_setgroups(const struct user_namespace *ns)
{
	return true;
}

static inline bool current_in_userns(const struct user_namespace *target_ns)
{
	return true;
}

static inline struct ns_common *ns_get_owner(struct ns_common *ns)
{
	return ERR_PTR(-EPERM);
}
#endif

#endif /* _LINUX_USER_H */
Commit	Line	Data
acce292c CLG	1	#ifndef _LINUX_USER_NAMESPACE_H
	2	#define _LINUX_USER_NAMESPACE_H
	3
	4	#include <linux/kref.h>
	5	#include <linux/nsproxy.h>
435d5f4b	6	#include <linux/ns_common.h>
acce292c	7	#include <linux/sched.h>
b2d5bfea	8	#include <linux/workqueue.h>
cd9c513b	9	#include <linux/rwsem.h>
cc5efc23	10	#include <linux/sysctl.h>
77ec739d	11	#include <linux/err.h>
acce292c	12
22d917d8 EB	13	#define UID_GID_MAP_MAX_EXTENTS 5
	14
	15	struct uid_gid_map { /* 64 bytes -- 1 cache line */
	16	u32 nr_extents;
	17	struct uid_gid_extent {
	18	u32 first;
	19	u32 lower_first;
	20	u32 count;
	21	} extent[UID_GID_MAP_MAX_EXTENTS];
	22	};
	23
9cc46516 EB	24	#define USERNS_SETGROUPS_ALLOWED 1UL
	25
	26	#define USERNS_INIT_FLAGS USERNS_SETGROUPS_ALLOWED
	27
f6b2db1a	28	struct ucounts;
25f9c081 EB	29
	30	enum ucount_type {
	31	UCOUNT_USER_NAMESPACES,
f333c700	32	UCOUNT_PID_NAMESPACES,
f7af3d1c	33	UCOUNT_UTS_NAMESPACES,
aba35661	34	UCOUNT_IPC_NAMESPACES,
70328660	35	UCOUNT_NET_NAMESPACES,
537f7ccb	36	UCOUNT_MNT_NAMESPACES,
d08311dd	37	UCOUNT_CGROUP_NAMESPACES,
1cce1eea NB	38	#ifdef CONFIG_INOTIFY_USER
	39	UCOUNT_INOTIFY_INSTANCES,
	40	UCOUNT_INOTIFY_WATCHES,
	41	#endif
25f9c081 EB	42	UCOUNT_COUNTS,
	43	};
	44
acce292c	45	struct user_namespace {
22d917d8 EB	46	struct uid_gid_map uid_map;
22d917d8 EB	47	struct uid_gid_map gid_map;
f76d207a	48	struct uid_gid_map projid_map;
c61a2810	49	atomic_t count;
aeb3ae9d	50	struct user_namespace *parent;
8742f229	51	int level;
783291e6 EB	52	kuid_t owner;
783291e6 EB	53	kgid_t group;
435d5f4b	54	struct ns_common ns;
9cc46516	55	unsigned long flags;
f36f8c75 DH	56
	57	/* Register of per-UID persistent keyrings for this namespace */
	58	#ifdef CONFIG_PERSISTENT_KEYRINGS
	59	struct key *persistent_keyring_register;
	60	struct rw_semaphore persistent_keyring_register_sem;
	61	#endif
b032132c	62	struct work_struct work;
dbec2846 EB	63	#ifdef CONFIG_SYSCTL
	64	struct ctl_table_set set;
	65	struct ctl_table_header *sysctls;
	66	#endif
f6b2db1a	67	struct ucounts *ucounts;
25f9c081	68	int ucount_max[UCOUNT_COUNTS];
3859a271	69	} __randomize_layout;
f6b2db1a EB	70
	71	struct ucounts {
	72	struct hlist_node node;
	73	struct user_namespace *ns;
	74	kuid_t uid;
040757f7	75	int count;
25f9c081	76	atomic_t ucount[UCOUNT_COUNTS];
acce292c CLG	77	};
	78
	79	extern struct user_namespace init_user_ns;
f6b2db1a EB	80
	81	bool setup_userns_sysctls(struct user_namespace *ns);
	82	void retire_userns_sysctls(struct user_namespace *ns);
25f9c081 EB	83	struct ucounts inc_ucount(struct user_namespace ns, kuid_t uid, enum ucount_type type);
25f9c081 EB	84	void dec_ucount(struct ucounts *ucounts, enum ucount_type type);
acce292c CLG	85
	86	#ifdef CONFIG_USER_NS
	87
	88	static inline struct user_namespace get_user_ns(struct user_namespace ns)
	89	{
	90	if (ns)
c61a2810	91	atomic_inc(&ns->count);
acce292c CLG	92	return ns;
	93	}
	94
18b6e041	95	extern int create_user_ns(struct cred *new);
b2e0d987	96	extern int unshare_userns(unsigned long unshare_flags, struct cred **new_cred);
b032132c	97	extern void __put_user_ns(struct user_namespace *ns);
acce292c CLG	98
	99	static inline void put_user_ns(struct user_namespace *ns)
	100	{
c61a2810	101	if (ns && atomic_dec_and_test(&ns->count))
b032132c	102	__put_user_ns(ns);
acce292c CLG	103	}
acce292c CLG	104
22d917d8	105	struct seq_operations;
ccf94f1b FF	106	extern const struct seq_operations proc_uid_seq_operations;
	107	extern const struct seq_operations proc_gid_seq_operations;
	108	extern const struct seq_operations proc_projid_seq_operations;
22d917d8 EB	109	extern ssize_t proc_uid_map_write(struct file , const char __user , size_t, loff_t *);
22d917d8 EB	110	extern ssize_t proc_gid_map_write(struct file , const char __user , size_t, loff_t *);
f76d207a	111	extern ssize_t proc_projid_map_write(struct file , const char __user , size_t, loff_t *);
9cc46516 EB	112	extern ssize_t proc_setgroups_write(struct file , const char __user , size_t, loff_t *);
9cc46516 EB	113	extern int proc_setgroups_show(struct seq_file m, void v);
273d2c67	114	extern bool userns_may_setgroups(const struct user_namespace *ns);
d07b846f	115	extern bool current_in_userns(const struct user_namespace *target_ns);
bcac25a5 AV	116
bcac25a5 AV	117	struct ns_common ns_get_owner(struct ns_common ns);
acce292c CLG	118	#else
	119
	120	static inline struct user_namespace get_user_ns(struct user_namespace ns)
	121	{
	122	return &init_user_ns;
	123	}
	124
18b6e041	125	static inline int create_user_ns(struct cred *new)
acce292c	126	{
18b6e041	127	return -EINVAL;
acce292c CLG	128	}
acce292c CLG	129
b2e0d987 EB	130	static inline int unshare_userns(unsigned long unshare_flags,
	131	struct cred **new_cred)
	132	{
	133	if (unshare_flags & CLONE_NEWUSER)
	134	return -EINVAL;
	135	return 0;
	136	}
	137
acce292c CLG	138	static inline void put_user_ns(struct user_namespace *ns)
	139	{
	140	}
	141
273d2c67 EB	142	static inline bool userns_may_setgroups(const struct user_namespace *ns)
	143	{
	144	return true;
	145	}
d07b846f SF	146
	147	static inline bool current_in_userns(const struct user_namespace *target_ns)
	148	{
	149	return true;
	150	}
bcac25a5 AV	151
	152	static inline struct ns_common ns_get_owner(struct ns_common ns)
	153	{
	154	return ERR_PTR(-EPERM);
	155	}
22d917d8 EB	156	#endif
22d917d8 EB	157
acce292c	158	#endif /* _LINUX_USER_H */