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11 .TH "SECURITY-FLAGS" "5" "May 5, 2014"
12 .SH "NAME"
13 \fBsecurity-flags\fR - process security flags
14 .SH "DESCRIPTION"
15 Each process on an illumos system has an associated set of security-flags
16 which describe additional per-process security and exploit mitigation
17 features which are enabled for that process.
18 .P
19 There are two sets of these flags for each process, the effective set
20 (abbreviated \fIE\fR) are the set which currently apply to the process and are
21 immutable. The inheritable set (abbreviated \fII\fR) are the flags which will
22 become effective the next time the process calls one of the \fBexec(2)\fR
23 family of functions, and will be inherited as both the effective and
24 inheritable sets by any child processes. The inheritable set may be changed
25 at any time, subject to permissions.
26 .P
27 To change the security-flags of a process one must have both permissions
28 equivalent to those required to send a signal to the process and have the
29 \fBPRIV_PROC_SECFLAGS\fR privilege.
30 .P
31 Currently available features are:
32
33 .sp
34 .ne 2
35 .na
36 Address Space Layout Randomisation (ASLR)
37 .ad
38 .RS 11n
39 The base addresses of the stack, heap and shared library (including
40 \fBld.so\fR) mappings are randomised, the bases of mapped regions other than
41 those using \fBMAP_FIXED\fR are randomised.
42 .P
43 Currently, executable base addresses are \fInot\fR randomised, due to which
44 the mitigation provided by this feature is currently limited.
45 .P
46 This flag may also be enabled by the presence of the \fBDT_SUNW_ASLR\fR
47 dynamic tag in the \fB.dynamic\fR section of the executable file. If this
48 tag has a value of 1, ASLR will be enabled. If the flag has a value of
49 \fB0\fR ASLR will be disabled. If the tag is not present, the value of the
50 ASLR flag will be inherited as normal.
51 .RE
52
53 System default security-flags are configured via properties on the
54 \fBsvc:/system/process-security\fR service, which contains a boolean property
55 per-flag in the \fBsecflags\fR property group. For example, to enable ASLR by
56 default you would execute the following commands:
57 .sp
58 .in +2
59 .nf
60 # svccfg -s svc:/system/process-security setprop secflags/aslr = true
61 .fi
62 .in -2
63 .sp
64 .P
65 This can be done by any user with the \fBsolaris.smf.value.process-security\fR
66 authorization.
67 .P
68 Since security-flags are strictly inherited, this will not take effect until
69 the system or zone is next booted.
70
71 .SH "SEE ALSO"
72 .BR psecflags (1),
73 .BR svccfg (1M),
74 .BR brk (2),
75 .BR exec (2),
76 .BR mmap (2),
77 .BR mmapobj (2),
78 .BR privileges (5),
79 .BR rbac (5)