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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_UIDGID_H
#define _LINUX_UIDGID_H
/*
* A set of types for the internal kernel types representing uids and gids.
*
* The types defined in this header allow distinguishing which uids and gids in
* the kernel are values used by userspace and which uid and gid values are
* the internal kernel values. With the addition of user namespaces the values
* can be different. Using the type system makes it possible for the compiler
* to detect when we overlook these differences.
*
*/
#include <linux/types.h>
#include <linux/highuid.h>
struct user_namespace;
extern struct user_namespace init_user_ns;
typedef struct {
uid_t val;
} kuid_t;
typedef struct {
gid_t val;
} kgid_t;
#define KUIDT_INIT(value) (kuid_t){ value }
#define KGIDT_INIT(value) (kgid_t){ value }
#ifdef CONFIG_MULTIUSER
static inline uid_t __kuid_val(kuid_t uid)
{
return uid.val;
}
static inline gid_t __kgid_val(kgid_t gid)
{
return gid.val;
}
#else
static inline uid_t __kuid_val(kuid_t uid)
{
return 0;
}
static inline gid_t __kgid_val(kgid_t gid)
{
return 0;
}
#endif
#define GLOBAL_ROOT_UID KUIDT_INIT(0)
#define GLOBAL_ROOT_GID KGIDT_INIT(0)
#define INVALID_UID KUIDT_INIT(-1)
#define INVALID_GID KGIDT_INIT(-1)
static inline bool uid_eq(kuid_t left, kuid_t right)
{
return __kuid_val(left) == __kuid_val(right);
}
static inline bool gid_eq(kgid_t left, kgid_t right)
{
return __kgid_val(left) == __kgid_val(right);
}
static inline bool uid_gt(kuid_t left, kuid_t right)
{
return __kuid_val(left) > __kuid_val(right);
}
static inline bool gid_gt(kgid_t left, kgid_t right)
{
return __kgid_val(left) > __kgid_val(right);
}
static inline bool uid_gte(kuid_t left, kuid_t right)
{
return __kuid_val(left) >= __kuid_val(right);
}
static inline bool gid_gte(kgid_t left, kgid_t right)
{
return __kgid_val(left) >= __kgid_val(right);
}
static inline bool uid_lt(kuid_t left, kuid_t right)
{
return __kuid_val(left) < __kuid_val(right);
}
static inline bool gid_lt(kgid_t left, kgid_t right)
{
return __kgid_val(left) < __kgid_val(right);
}
static inline bool uid_lte(kuid_t left, kuid_t right)
{
return __kuid_val(left) <= __kuid_val(right);
}
static inline bool gid_lte(kgid_t left, kgid_t right)
{
return __kgid_val(left) <= __kgid_val(right);
}
static inline bool uid_valid(kuid_t uid)
{
return __kuid_val(uid) != (uid_t) -1;
}
static inline bool gid_valid(kgid_t gid)
{
return __kgid_val(gid) != (gid_t) -1;
}
#ifdef CONFIG_USER_NS
extern kuid_t make_kuid(struct user_namespace *from, uid_t uid);
extern kgid_t make_kgid(struct user_namespace *from, gid_t gid);
extern uid_t from_kuid(struct user_namespace *to, kuid_t uid);
extern gid_t from_kgid(struct user_namespace *to, kgid_t gid);
extern uid_t from_kuid_munged(struct user_namespace *to, kuid_t uid);
extern gid_t from_kgid_munged(struct user_namespace *to, kgid_t gid);
static inline bool kuid_has_mapping(struct user_namespace *ns, kuid_t uid)
{
return from_kuid(ns, uid) != (uid_t) -1;
}
static inline bool kgid_has_mapping(struct user_namespace *ns, kgid_t gid)
{
return from_kgid(ns, gid) != (gid_t) -1;
}
#else
static inline kuid_t make_kuid(struct user_namespace *from, uid_t uid)
{
return KUIDT_INIT(uid);
}
static inline kgid_t make_kgid(struct user_namespace *from, gid_t gid)
{
return KGIDT_INIT(gid);
}
static inline uid_t from_kuid(struct user_namespace *to, kuid_t kuid)
{
return __kuid_val(kuid);
}
static inline gid_t from_kgid(struct user_namespace *to, kgid_t kgid)
{
return __kgid_val(kgid);
}
static inline uid_t from_kuid_munged(struct user_namespace *to, kuid_t kuid)
{
uid_t uid = from_kuid(to, kuid);
if (uid == (uid_t)-1)
uid = overflowuid;
return uid;
}
static inline gid_t from_kgid_munged(struct user_namespace *to, kgid_t kgid)
{
gid_t gid = from_kgid(to, kgid);
if (gid == (gid_t)-1)
gid = overflowgid;
return gid;
}
static inline bool kuid_has_mapping(struct user_namespace *ns, kuid_t uid)
{
return uid_valid(uid);
}
static inline bool kgid_has_mapping(struct user_namespace *ns, kgid_t gid)
{
return gid_valid(gid);
}
#endif /* CONFIG_USER_NS */
#endif /* _LINUX_UIDGID_H */