securebits.h

   1 #ifndef _LINUX_SECUREBITS_H
   2 #define _LINUX_SECUREBITS_H 1
   3
   4 /* This is minimal version of Linux' linux/securebits.h header file,
   5  * which is licensed GPL2 */
   6
   7 #define SECUREBITS_DEFAULT 0x00000000
   8
   9 /* When set UID 0 has no special privileges. When unset, we support
  10    inheritance of root-permissions and suid-root executable under
  11    compatibility mode. We raise the effective and inheritable bitmasks
  12    *of the executable file* if the effective uid of the new process is
  13    0. If the real uid is 0, we raise the effective (legacy) bit of the
  14    executable file. */
  15 #define SECURE_NOROOT                   0
  16 #define SECURE_NOROOT_LOCKED            1  /* make bit-0 immutable */
  17
  18 /* When set, setuid to/from uid 0 does not trigger capability-"fixup".
  19    When unset, to provide compatiblility with old programs relying on
  20    set*uid to gain/lose privilege, transitions to/from uid 0 cause
  21    capabilities to be gained/lost. */
  22 #define SECURE_NO_SETUID_FIXUP          2
  23 #define SECURE_NO_SETUID_FIXUP_LOCKED   3  /* make bit-2 immutable */
  24
  25 /* When set, a process can retain its capabilities even after
  26    transitioning to a non-root user (the set-uid fixup suppressed by
  27    bit 2). Bit-4 is cleared when a process calls exec(); setting both
  28    bit 4 and 5 will create a barrier through exec that no exec()'d
  29    child can use this feature again. */
  30 #define SECURE_KEEP_CAPS                4
  31 #define SECURE_KEEP_CAPS_LOCKED         5  /* make bit-4 immutable */
  32
  33 /* Each securesetting is implemented using two bits. One bit specifies
  34    whether the setting is on or off. The other bit specify whether the
  35    setting is locked or not. A setting which is locked cannot be
  36    changed from user-level. */
  37 #define issecure_mask(X)        (1 << (X))
  38 #define issecure(X)             (issecure_mask(X) & current_cred_xxx(securebits))
  39
  40 #define SECURE_ALL_BITS         (issecure_mask(SECURE_NOROOT) | \
  41                                  issecure_mask(SECURE_NO_SETUID_FIXUP) | \
  42                                  issecure_mask(SECURE_KEEP_CAPS))
  43 #define SECURE_ALL_LOCKS        (SECURE_ALL_BITS << 1)
  44
  45 #endif /* !_LINUX_SECUREBITS_H */