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Diffstat (limited to 'include/linux/uidgid.h')
| -rw-r--r-- | include/linux/uidgid.h | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/include/linux/uidgid.h b/include/linux/uidgid.h new file mode 100644 index 000000000..03835522d --- /dev/null +++ b/include/linux/uidgid.h @@ -0,0 +1,190 @@ +#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 true; +} + +static inline bool kgid_has_mapping(struct user_namespace *ns, kgid_t gid) +{ + return true; +} + +#endif /* CONFIG_USER_NS */ + +#endif /* _LINUX_UIDGID_H */ |