mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-30 16:13:54 +08:00
98 lines
3.1 KiB
C
98 lines
3.1 KiB
C
#ifndef _LINUX_HIGHUID_H
|
|
#define _LINUX_HIGHUID_H
|
|
|
|
#include <linux/types.h>
|
|
|
|
/*
|
|
* general notes:
|
|
*
|
|
* CONFIG_UID16 is defined if the given architecture needs to
|
|
* support backwards compatibility for old system calls.
|
|
*
|
|
* kernel code should use uid_t and gid_t at all times when dealing with
|
|
* kernel-private data.
|
|
*
|
|
* old_uid_t and old_gid_t should only be different if CONFIG_UID16 is
|
|
* defined, else the platform should provide dummy typedefs for them
|
|
* such that they are equivalent to __kernel_{u,g}id_t.
|
|
*
|
|
* uid16_t and gid16_t are used on all architectures. (when dealing
|
|
* with structures hard coded to 16 bits, such as in filesystems)
|
|
*/
|
|
|
|
|
|
/*
|
|
* This is the "overflow" UID and GID. They are used to signify uid/gid
|
|
* overflow to old programs when they request uid/gid information but are
|
|
* using the old 16 bit interfaces.
|
|
* When you run a libc5 program, it will think that all highuid files or
|
|
* processes are owned by this uid/gid.
|
|
* The idea is that it's better to do so than possibly return 0 in lieu of
|
|
* 65536, etc.
|
|
*/
|
|
|
|
extern int overflowuid;
|
|
extern int overflowgid;
|
|
|
|
extern void __bad_uid(void);
|
|
extern void __bad_gid(void);
|
|
|
|
#define DEFAULT_OVERFLOWUID 65534
|
|
#define DEFAULT_OVERFLOWGID 65534
|
|
|
|
#ifdef CONFIG_UID16
|
|
|
|
/* prevent uid mod 65536 effect by returning a default value for high UIDs */
|
|
#define high2lowuid(uid) ((uid) & ~0xFFFF ? (old_uid_t)overflowuid : (old_uid_t)(uid))
|
|
#define high2lowgid(gid) ((gid) & ~0xFFFF ? (old_gid_t)overflowgid : (old_gid_t)(gid))
|
|
/*
|
|
* -1 is different in 16 bits than it is in 32 bits
|
|
* these macros are used by chown(), setreuid(), ...,
|
|
*/
|
|
#define low2highuid(uid) ((uid) == (old_uid_t)-1 ? (uid_t)-1 : (uid_t)(uid))
|
|
#define low2highgid(gid) ((gid) == (old_gid_t)-1 ? (gid_t)-1 : (gid_t)(gid))
|
|
|
|
#define __convert_uid(size, uid) \
|
|
(size >= sizeof(uid) ? (uid) : high2lowuid(uid))
|
|
#define __convert_gid(size, gid) \
|
|
(size >= sizeof(gid) ? (gid) : high2lowgid(gid))
|
|
|
|
|
|
#else
|
|
|
|
#define __convert_uid(size, uid) (uid)
|
|
#define __convert_gid(size, gid) (gid)
|
|
|
|
#endif /* !CONFIG_UID16 */
|
|
|
|
/* uid/gid input should be always 32bit uid_t */
|
|
#define SET_UID(var, uid) do { (var) = __convert_uid(sizeof(var), (uid)); } while (0)
|
|
#define SET_GID(var, gid) do { (var) = __convert_gid(sizeof(var), (gid)); } while (0)
|
|
|
|
/*
|
|
* Everything below this line is needed on all architectures, to deal with
|
|
* filesystems that only store 16 bits of the UID/GID, etc.
|
|
*/
|
|
|
|
/*
|
|
* This is the UID and GID that will get written to disk if a filesystem
|
|
* only supports 16-bit UIDs and the kernel has a high UID/GID to write
|
|
*/
|
|
extern int fs_overflowuid;
|
|
extern int fs_overflowgid;
|
|
|
|
#define DEFAULT_FS_OVERFLOWUID 65534
|
|
#define DEFAULT_FS_OVERFLOWGID 65534
|
|
|
|
/*
|
|
* Since these macros are used in architectures that only need limited
|
|
* 16-bit UID back compatibility, we won't use old_uid_t and old_gid_t
|
|
*/
|
|
#define fs_high2lowuid(uid) ((uid) & ~0xFFFF ? (uid16_t)fs_overflowuid : (uid16_t)(uid))
|
|
#define fs_high2lowgid(gid) ((gid) & ~0xFFFF ? (gid16_t)fs_overflowgid : (gid16_t)(gid))
|
|
|
|
#define low_16_bits(x) ((x) & 0xFFFF)
|
|
#define high_16_bits(x) (((x) & 0xFFFF0000) >> 16)
|
|
|
|
#endif /* _LINUX_HIGHUID_H */
|