uidgid.h 3.5 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177
  1. #ifndef _LINUX_UIDGID_H
  2. #define _LINUX_UIDGID_H
  3. /*
  4. * A set of types for the internal kernel types representing uids and gids.
  5. *
  6. * The types defined in this header allow distinguishing which uids and gids in
  7. * the kernel are values used by userspace and which uid and gid values are
  8. * the internal kernel values. With the addition of user namespaces the values
  9. * can be different. Using the type system makes it possible for the compiler
  10. * to detect when we overlook these differences.
  11. *
  12. */
  13. #include <linux/types.h>
  14. #include <linux/highuid.h>
  15. struct user_namespace;
  16. extern struct user_namespace init_user_ns;
  17. #if defined(NOTYET)
  18. typedef struct {
  19. uid_t val;
  20. } kuid_t;
  21. typedef struct {
  22. gid_t val;
  23. } kgid_t;
  24. #define KUIDT_INIT(value) (kuid_t){ value }
  25. #define KGIDT_INIT(value) (kgid_t){ value }
  26. static inline uid_t __kuid_val(kuid_t uid)
  27. {
  28. return uid.val;
  29. }
  30. static inline gid_t __kgid_val(kgid_t gid)
  31. {
  32. return gid.val;
  33. }
  34. #else
  35. typedef uid_t kuid_t;
  36. typedef gid_t kgid_t;
  37. static inline uid_t __kuid_val(kuid_t uid)
  38. {
  39. return uid;
  40. }
  41. static inline gid_t __kgid_val(kgid_t gid)
  42. {
  43. return gid;
  44. }
  45. #define KUIDT_INIT(value) ((kuid_t) value )
  46. #define KGIDT_INIT(value) ((kgid_t) value )
  47. #endif
  48. #define GLOBAL_ROOT_UID KUIDT_INIT(0)
  49. #define GLOBAL_ROOT_GID KGIDT_INIT(0)
  50. #define INVALID_UID KUIDT_INIT(-1)
  51. #define INVALID_GID KGIDT_INIT(-1)
  52. static inline bool uid_eq(kuid_t left, kuid_t right)
  53. {
  54. return __kuid_val(left) == __kuid_val(right);
  55. }
  56. static inline bool gid_eq(kgid_t left, kgid_t right)
  57. {
  58. return __kgid_val(left) == __kgid_val(right);
  59. }
  60. static inline bool uid_gt(kuid_t left, kuid_t right)
  61. {
  62. return __kuid_val(left) > __kuid_val(right);
  63. }
  64. static inline bool gid_gt(kgid_t left, kgid_t right)
  65. {
  66. return __kgid_val(left) > __kgid_val(right);
  67. }
  68. static inline bool uid_gte(kuid_t left, kuid_t right)
  69. {
  70. return __kuid_val(left) >= __kuid_val(right);
  71. }
  72. static inline bool gid_gte(kgid_t left, kgid_t right)
  73. {
  74. return __kgid_val(left) >= __kgid_val(right);
  75. }
  76. static inline bool uid_lt(kuid_t left, kuid_t right)
  77. {
  78. return __kuid_val(left) < __kuid_val(right);
  79. }
  80. static inline bool gid_lt(kgid_t left, kgid_t right)
  81. {
  82. return __kgid_val(left) < __kgid_val(right);
  83. }
  84. static inline bool uid_lte(kuid_t left, kuid_t right)
  85. {
  86. return __kuid_val(left) <= __kuid_val(right);
  87. }
  88. static inline bool gid_lte(kgid_t left, kgid_t right)
  89. {
  90. return __kgid_val(left) <= __kgid_val(right);
  91. }
  92. static inline bool uid_valid(kuid_t uid)
  93. {
  94. return !uid_eq(uid, INVALID_UID);
  95. }
  96. static inline bool gid_valid(kgid_t gid)
  97. {
  98. return !gid_eq(gid, INVALID_GID);
  99. }
  100. static inline kuid_t make_kuid(struct user_namespace *from, uid_t uid)
  101. {
  102. return KUIDT_INIT(uid);
  103. }
  104. static inline kgid_t make_kgid(struct user_namespace *from, gid_t gid)
  105. {
  106. return KGIDT_INIT(gid);
  107. }
  108. static inline uid_t from_kuid(struct user_namespace *to, kuid_t kuid)
  109. {
  110. return __kuid_val(kuid);
  111. }
  112. static inline gid_t from_kgid(struct user_namespace *to, kgid_t kgid)
  113. {
  114. return __kgid_val(kgid);
  115. }
  116. static inline uid_t from_kuid_munged(struct user_namespace *to, kuid_t kuid)
  117. {
  118. uid_t uid = from_kuid(to, kuid);
  119. if (uid == (uid_t)-1)
  120. uid = overflowuid;
  121. return uid;
  122. }
  123. static inline gid_t from_kgid_munged(struct user_namespace *to, kgid_t kgid)
  124. {
  125. gid_t gid = from_kgid(to, kgid);
  126. if (gid == (gid_t)-1)
  127. gid = overflowgid;
  128. return gid;
  129. }
  130. static inline bool kuid_has_mapping(struct user_namespace *ns, kuid_t uid)
  131. {
  132. return true;
  133. }
  134. static inline bool kgid_has_mapping(struct user_namespace *ns, kgid_t gid)
  135. {
  136. return true;
  137. }
  138. #endif /* _LINUX_UIDGID_H */