1#ifndef _LINUX_SECUREBITS_H 2#define _LINUX_SECUREBITS_H 1 3 4/* Each securesetting is implemented using two bits. One bit specifies 5 whether the setting is on or off. The other bit specify whether the 6 setting is locked or not. A setting which is locked cannot be 7 changed from user-level. */ 8#define issecure_mask(X) (1 << (X)) 9#ifdef __KERNEL__ 10#define issecure(X) (issecure_mask(X) & current_cred_xxx(securebits)) 11#endif 12 13#define SECUREBITS_DEFAULT 0x00000000 14 15/* When set UID 0 has no special privileges. When unset, we support 16 inheritance of root-permissions and suid-root executable under 17 compatibility mode. We raise the effective and inheritable bitmasks 18 *of the executable file* if the effective uid of the new process is 19 0. If the real uid is 0, we raise the effective (legacy) bit of the 20 executable file. */ 21#define SECURE_NOROOT 0 22#define SECURE_NOROOT_LOCKED 1 /* make bit-0 immutable */ 23 24#define SECBIT_NOROOT (issecure_mask(SECURE_NOROOT)) 25#define SECBIT_NOROOT_LOCKED (issecure_mask(SECURE_NOROOT_LOCKED)) 26 27/* When set, setuid to/from uid 0 does not trigger capability-"fixup". 28 When unset, to provide compatiblility with old programs relying on 29 set*uid to gain/lose privilege, transitions to/from uid 0 cause 30 capabilities to be gained/lost. */ 31#define SECURE_NO_SETUID_FIXUP 2 32#define SECURE_NO_SETUID_FIXUP_LOCKED 3 /* make bit-2 immutable */ 33 34#define SECBIT_NO_SETUID_FIXUP (issecure_mask(SECURE_NO_SETUID_FIXUP)) 35#define SECBIT_NO_SETUID_FIXUP_LOCKED \ 36 (issecure_mask(SECURE_NO_SETUID_FIXUP_LOCKED)) 37 38/* When set, a process can retain its capabilities even after 39 transitioning to a non-root user (the set-uid fixup suppressed by 40 bit 2). Bit-4 is cleared when a process calls exec(); setting both 41 bit 4 and 5 will create a barrier through exec that no exec()'d 42 child can use this feature again. */ 43#define SECURE_KEEP_CAPS 4 44#define SECURE_KEEP_CAPS_LOCKED 5 /* make bit-4 immutable */ 45 46#define SECBIT_KEEP_CAPS (issecure_mask(SECURE_KEEP_CAPS)) 47#define SECBIT_KEEP_CAPS_LOCKED (issecure_mask(SECURE_KEEP_CAPS_LOCKED)) 48 49#define SECURE_ALL_BITS (issecure_mask(SECURE_NOROOT) | \ 50 issecure_mask(SECURE_NO_SETUID_FIXUP) | \ 51 issecure_mask(SECURE_KEEP_CAPS)) 52#define SECURE_ALL_LOCKS (SECURE_ALL_BITS << 1) 53 54#endif /* !_LINUX_SECUREBITS_H */ 55