linux-stable/include/linux/proc_ns.h
Jakub Kicinski cdab6ba866 nsfs: generalize ns_get_path() for path resolution with a task
ns_get_path() takes struct task_struct and proc_ns_ops as its
parameters.  For path resolution directly from a namespace,
e.g. based on a networking device's net name space, we need
more flexibility.  Add a ns_get_path_cb() helper which will
allow callers to use any method of obtaining the name space
reference.  Convert ns_get_path() to use ns_get_path_cb().

Following patches will bring a networking user.

CC: Eric W. Biederman <ebiederm@xmission.com>
Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-31 16:12:23 +01:00

89 lines
2.6 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* procfs namespace bits
*/
#ifndef _LINUX_PROC_NS_H
#define _LINUX_PROC_NS_H
#include <linux/ns_common.h>
struct pid_namespace;
struct nsproxy;
struct path;
struct task_struct;
struct inode;
struct proc_ns_operations {
const char *name;
const char *real_ns_name;
int type;
struct ns_common *(*get)(struct task_struct *task);
void (*put)(struct ns_common *ns);
int (*install)(struct nsproxy *nsproxy, struct ns_common *ns);
struct user_namespace *(*owner)(struct ns_common *ns);
struct ns_common *(*get_parent)(struct ns_common *ns);
} __randomize_layout;
extern const struct proc_ns_operations netns_operations;
extern const struct proc_ns_operations utsns_operations;
extern const struct proc_ns_operations ipcns_operations;
extern const struct proc_ns_operations pidns_operations;
extern const struct proc_ns_operations pidns_for_children_operations;
extern const struct proc_ns_operations userns_operations;
extern const struct proc_ns_operations mntns_operations;
extern const struct proc_ns_operations cgroupns_operations;
/*
* We always define these enumerators
*/
enum {
PROC_ROOT_INO = 1,
PROC_IPC_INIT_INO = 0xEFFFFFFFU,
PROC_UTS_INIT_INO = 0xEFFFFFFEU,
PROC_USER_INIT_INO = 0xEFFFFFFDU,
PROC_PID_INIT_INO = 0xEFFFFFFCU,
PROC_CGROUP_INIT_INO = 0xEFFFFFFBU,
};
#ifdef CONFIG_PROC_FS
extern int pid_ns_prepare_proc(struct pid_namespace *ns);
extern void pid_ns_release_proc(struct pid_namespace *ns);
extern int proc_alloc_inum(unsigned int *pino);
extern void proc_free_inum(unsigned int inum);
#else /* CONFIG_PROC_FS */
static inline int pid_ns_prepare_proc(struct pid_namespace *ns) { return 0; }
static inline void pid_ns_release_proc(struct pid_namespace *ns) {}
static inline int proc_alloc_inum(unsigned int *inum)
{
*inum = 1;
return 0;
}
static inline void proc_free_inum(unsigned int inum) {}
#endif /* CONFIG_PROC_FS */
static inline int ns_alloc_inum(struct ns_common *ns)
{
atomic_long_set(&ns->stashed, 0);
return proc_alloc_inum(&ns->inum);
}
#define ns_free_inum(ns) proc_free_inum((ns)->inum)
extern struct file *proc_ns_fget(int fd);
#define get_proc_ns(inode) ((struct ns_common *)(inode)->i_private)
extern void *ns_get_path(struct path *path, struct task_struct *task,
const struct proc_ns_operations *ns_ops);
typedef struct ns_common *ns_get_path_helper_t(void *);
extern void *ns_get_path_cb(struct path *path, ns_get_path_helper_t ns_get_cb,
void *private_data);
extern int ns_get_name(char *buf, size_t size, struct task_struct *task,
const struct proc_ns_operations *ns_ops);
extern void nsfs_init(void);
#endif /* _LINUX_PROC_NS_H */