1firstboot_selinux(8) SELinux Policy firstboot firstboot_selinux(8)
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6 firstboot_selinux - Security Enhanced Linux Policy for the firstboot
7 processes
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10 Security-Enhanced Linux secures the firstboot processes via flexible
11 mandatory access control.
12 The firstboot processes execute with the firstboot_t SELinux type. You
14 can check if you have these processes running by executing the ps com‐
15 mand with the -Z qualifier.
16 For example:
18 ps -eZ | grep firstboot_t
20
24 The firstboot_t SELinux type can be entered via the firstboot_exec_t
25 file type.
26 The default entrypoint paths for the firstboot_t domain are the follow‐
28 ing:
29 /usr/sbin/firstboot, /usr/share/firstboot/firstboot.py
31
33 SELinux defines process types (domains) for each process running on the
34 system
35 You can see the context of a process using the -Z option to ps
37 Policy governs the access confined processes have to files. SELinux
39 firstboot policy is very flexible allowing users to setup their first‐
40 boot processes in as secure a method as possible.
41 The following process types are defined for firstboot:
43 firstboot_t
45 Note: semanage permissive -a firstboot_t can be used to make the
47 process type firstboot_t permissive. SELinux does not deny access to
48 permissive process types, but the AVC (SELinux denials) messages are
49 still generated.
50
53 SELinux policy is customizable based on least access required. first‐
54 boot policy is extremely flexible and has several booleans that allow
55 you to manipulate the policy and run firstboot with the tightest access
56 possible.
57 If you want to deny user domains applications to map a memory region as
61 both executable and writable, this is dangerous and the executable
62 should be reported in bugzilla, you must turn on the deny_execmem bool‐
63 ean. Enabled by default.
64 setsebool -P deny_execmem 1
66 If you want to allow all domains to execute in fips_mode, you must turn
70 on the fips_mode boolean. Enabled by default.
71 setsebool -P fips_mode 1
73 If you want to control the ability to mmap a low area of the address
77 space, as configured by /proc/sys/vm/mmap_min_addr, you must turn on
78 the mmap_low_allowed boolean. Disabled by default.
79 setsebool -P mmap_low_allowed 1
81 If you want to allow confined applications to use nscd shared memory,
85 you must turn on the nscd_use_shm boolean. Enabled by default.
86 setsebool -P nscd_use_shm 1
88 If you want to disable kernel module loading, you must turn on the
92 secure_mode_insmod boolean. Enabled by default.
93 setsebool -P secure_mode_insmod 1
95 If you want to allow unconfined executables to make their heap memory
99 executable. Doing this is a really bad idea. Probably indicates a
100 badly coded executable, but could indicate an attack. This executable
101 should be reported in bugzilla, you must turn on the selin‐
102 uxuser_execheap boolean. Disabled by default.
103 setsebool -P selinuxuser_execheap 1
105 If you want to allow unconfined executables to make their stack exe‐
109 cutable. This should never, ever be necessary. Probably indicates a
110 badly coded executable, but could indicate an attack. This executable
111 should be reported in bugzilla, you must turn on the selinuxuser_exec‐
112 stack boolean. Enabled by default.
113 setsebool -P selinuxuser_execstack 1
115
119 The SELinux process type firstboot_t can manage files labeled with the
120 following file types. The paths listed are the default paths for these
121 file types. Note the processes UID still need to have DAC permissions.
122 file_type
124 all files on the system
126
129 SELinux requires files to have an extended attribute to define the file
130 type.
131 You can see the context of a file using the -Z option to ls
133 Policy governs the access confined processes have to these files.
135 SELinux firstboot policy is very flexible allowing users to setup their
136 firstboot processes in as secure a method as possible.
137 STANDARD FILE CONTEXT
139 SELinux defines the file context types for the firstboot, if you wanted
141 to store files with these types in a diffent paths, you need to execute
142 the semanage command to sepecify alternate labeling and then use
143 restorecon to put the labels on disk.
144 semanage fcontext -a -t firstboot_etc_t '/srv/myfirstboot_con‐
146 tent(/.*)?'
147 restorecon -R -v /srv/myfirstboot_content
148 Note: SELinux often uses regular expressions to specify labels that
150 match multiple files.
151 The following file types are defined for firstboot:
153 firstboot_etc_t
157 - Set files with the firstboot_etc_t type, if you want to store first‐
159 boot files in the /etc directories.
160 firstboot_exec_t
164 - Set files with the firstboot_exec_t type, if you want to transition
166 an executable to the firstboot_t domain.
167 Paths:
170 /usr/sbin/firstboot, /usr/share/firstboot/firstboot.py
171 Note: File context can be temporarily modified with the chcon command.
174 If you want to permanently change the file context you need to use the
175 semanage fcontext command. This will modify the SELinux labeling data‐
176 base. You will need to use restorecon to apply the labels.
177
180 semanage fcontext can also be used to manipulate default file context
181 mappings.
182 semanage permissive can also be used to manipulate whether or not a
184 process type is permissive.
185 semanage module can also be used to enable/disable/install/remove pol‐
187 icy modules.
188 semanage boolean can also be used to manipulate the booleans
190 system-config-selinux is a GUI tool available to customize SELinux pol‐
193 icy settings.
194
197 This manual page was auto-generated using sepolicy manpage .
198
201 selinux(8), firstboot(8), semanage(8), restorecon(8), chcon(1), sepol‐
202 icy(8), setsebool(8)
203firstboot 19-06-18 firstboot_selinux(8)