1/* SPDX-License-Identifier: GPL-2.0 */ 2#ifndef _LINUX_UIDGID_H 3#define _LINUX_UIDGID_H 4 5/* 6 * A set of types for the internal kernel types representing uids and gids. 7 * 8 * The types defined in this header allow distinguishing which uids and gids in 9 * the kernel are values used by userspace and which uid and gid values are 10 * the internal kernel values. With the addition of user namespaces the values 11 * can be different. Using the type system makes it possible for the compiler 12 * to detect when we overlook these differences. 13 * 14 */ 15#include <linux/uidgid_types.h> 16#include <linux/highuid.h> 17 18struct user_namespace; 19extern struct user_namespace init_user_ns; 20struct uid_gid_map; 21 22#define KUIDT_INIT(value) (kuid_t){ value } 23#define KGIDT_INIT(value) (kgid_t){ value } 24 25#ifdef CONFIG_MULTIUSER 26static inline uid_t __kuid_val(kuid_t uid) 27{ 28 return uid.val; 29} 30 31static inline gid_t __kgid_val(kgid_t gid) 32{ 33 return gid.val; 34} 35#else 36static inline uid_t __kuid_val(kuid_t uid) 37{ 38 return 0; 39} 40 41static inline gid_t __kgid_val(kgid_t gid) 42{ 43 return 0; 44} 45#endif 46 47#define GLOBAL_ROOT_UID KUIDT_INIT(0) 48#define GLOBAL_ROOT_GID KGIDT_INIT(0) 49 50#define INVALID_UID KUIDT_INIT(-1) 51#define INVALID_GID KGIDT_INIT(-1) 52 53static inline bool uid_eq(kuid_t left, kuid_t right) 54{ 55 return __kuid_val(left) == __kuid_val(right); 56} 57 58static inline bool gid_eq(kgid_t left, kgid_t right) 59{ 60 return __kgid_val(left) == __kgid_val(right); 61} 62 63static inline bool uid_gt(kuid_t left, kuid_t right) 64{ 65 return __kuid_val(left) > __kuid_val(right); 66} 67 68static inline bool gid_gt(kgid_t left, kgid_t right) 69{ 70 return __kgid_val(left) > __kgid_val(right); 71} 72 73static inline bool uid_gte(kuid_t left, kuid_t right) 74{ 75 return __kuid_val(left) >= __kuid_val(right); 76} 77 78static inline bool gid_gte(kgid_t left, kgid_t right) 79{ 80 return __kgid_val(left) >= __kgid_val(right); 81} 82 83static inline bool uid_lt(kuid_t left, kuid_t right) 84{ 85 return __kuid_val(left) < __kuid_val(right); 86} 87 88static inline bool gid_lt(kgid_t left, kgid_t right) 89{ 90 return __kgid_val(left) < __kgid_val(right); 91} 92 93static inline bool uid_lte(kuid_t left, kuid_t right) 94{ 95 return __kuid_val(left) <= __kuid_val(right); 96} 97 98static inline bool gid_lte(kgid_t left, kgid_t right) 99{ 100 return __kgid_val(left) <= __kgid_val(right); 101} 102 103static inline bool uid_valid(kuid_t uid) 104{ 105 return __kuid_val(uid) != (uid_t) -1; 106} 107 108static inline bool gid_valid(kgid_t gid) 109{ 110 return __kgid_val(gid) != (gid_t) -1; 111} 112 113#ifdef CONFIG_USER_NS 114 115extern kuid_t make_kuid(struct user_namespace *from, uid_t uid); 116extern kgid_t make_kgid(struct user_namespace *from, gid_t gid); 117 118extern uid_t from_kuid(struct user_namespace *to, kuid_t uid); 119extern gid_t from_kgid(struct user_namespace *to, kgid_t gid); 120extern uid_t from_kuid_munged(struct user_namespace *to, kuid_t uid); 121extern gid_t from_kgid_munged(struct user_namespace *to, kgid_t gid); 122 123static inline bool kuid_has_mapping(struct user_namespace *ns, kuid_t uid) 124{ 125 return from_kuid(ns, uid) != (uid_t) -1; 126} 127 128static inline bool kgid_has_mapping(struct user_namespace *ns, kgid_t gid) 129{ 130 return from_kgid(ns, gid) != (gid_t) -1; 131} 132 133u32 map_id_down(struct uid_gid_map *map, u32 id); 134u32 map_id_up(struct uid_gid_map *map, u32 id); 135 136#else 137 138static inline kuid_t make_kuid(struct user_namespace *from, uid_t uid) 139{ 140 return KUIDT_INIT(uid); 141} 142 143static inline kgid_t make_kgid(struct user_namespace *from, gid_t gid) 144{ 145 return KGIDT_INIT(gid); 146} 147 148static inline uid_t from_kuid(struct user_namespace *to, kuid_t kuid) 149{ 150 return __kuid_val(kuid); 151} 152 153static inline gid_t from_kgid(struct user_namespace *to, kgid_t kgid) 154{ 155 return __kgid_val(kgid); 156} 157 158static inline uid_t from_kuid_munged(struct user_namespace *to, kuid_t kuid) 159{ 160 uid_t uid = from_kuid(to, kuid); 161 if (uid == (uid_t)-1) 162 uid = overflowuid; 163 return uid; 164} 165 166static inline gid_t from_kgid_munged(struct user_namespace *to, kgid_t kgid) 167{ 168 gid_t gid = from_kgid(to, kgid); 169 if (gid == (gid_t)-1) 170 gid = overflowgid; 171 return gid; 172} 173 174static inline bool kuid_has_mapping(struct user_namespace *ns, kuid_t uid) 175{ 176 return uid_valid(uid); 177} 178 179static inline bool kgid_has_mapping(struct user_namespace *ns, kgid_t gid) 180{ 181 return gid_valid(gid); 182} 183 184static inline u32 map_id_down(struct uid_gid_map *map, u32 id) 185{ 186 return id; 187} 188 189static inline u32 map_id_up(struct uid_gid_map *map, u32 id) 190{ 191 return id; 192} 193#endif /* CONFIG_USER_NS */ 194 195#endif /* _LINUX_UIDGID_H */ 196