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