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
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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 control the ability to mmap a low area of the address
70 space, as configured by /proc/sys/vm/mmap_min_addr, you must turn on
71 the mmap_low_allowed boolean. Disabled by default.
72 setsebool -P mmap_low_allowed 1
74 If you want to disable kernel module loading, you must turn on the se‐
78 cure_mode_insmod boolean. Enabled by default.
79 setsebool -P secure_mode_insmod 1
81 If you want to allow unconfined executables to make their heap memory
85 executable. Doing this is a really bad idea. Probably indicates a
86 badly coded executable, but could indicate an attack. This executable
87 should be reported in bugzilla, you must turn on the selinuxuser_ex‐
88 echeap boolean. Disabled by default.
89 setsebool -P selinuxuser_execheap 1
91 If you want to allow unconfined executables to make their stack exe‐
95 cutable. This should never, ever be necessary. Probably indicates a
96 badly coded executable, but could indicate an attack. This executable
97 should be reported in bugzilla, you must turn on the selinuxuser_exec‐
98 stack boolean. Enabled by default.
99 setsebool -P selinuxuser_execstack 1
101
105 The SELinux process type firstboot_t can manage files labeled with the
106 following file types. The paths listed are the default paths for these
107 file types. Note the processes UID still need to have DAC permissions.
108 file_type
110 all files on the system
112
115 SELinux requires files to have an extended attribute to define the file
116 type.
117 You can see the context of a file using the -Z option to ls
119 Policy governs the access confined processes have to these files.
121 SELinux firstboot policy is very flexible allowing users to setup their
122 firstboot processes in as secure a method as possible.
123 STANDARD FILE CONTEXT
125 SELinux defines the file context types for the firstboot, if you wanted
127 to store files with these types in a diffent paths, you need to execute
128 the semanage command to specify alternate labeling and then use re‐
129 storecon to put the labels on disk.
130 semanage fcontext -a -t firstboot_etc_t '/srv/myfirstboot_con‐
132 tent(/.*)?'
133 restorecon -R -v /srv/myfirstboot_content
134 Note: SELinux often uses regular expressions to specify labels that
136 match multiple files.
137 The following file types are defined for firstboot:
139 firstboot_etc_t
143 - Set files with the firstboot_etc_t type, if you want to store first‐
145 boot files in the /etc directories.
146 firstboot_exec_t
150 - Set files with the firstboot_exec_t type, if you want to transition
152 an executable to the firstboot_t domain.
153 Paths:
156 /usr/sbin/firstboot, /usr/share/firstboot/firstboot.py
157 Note: File context can be temporarily modified with the chcon command.
160 If you want to permanently change the file context you need to use the
161 semanage fcontext command. This will modify the SELinux labeling data‐
162 base. You will need to use restorecon to apply the labels.
163
166 semanage fcontext can also be used to manipulate default file context
167 mappings.
168 semanage permissive can also be used to manipulate whether or not a
170 process type is permissive.
171 semanage module can also be used to enable/disable/install/remove pol‐
173 icy modules.
174 semanage boolean can also be used to manipulate the booleans
176 system-config-selinux is a GUI tool available to customize SELinux pol‐
179 icy settings.
180
183 This manual page was auto-generated using sepolicy manpage .
184
187 selinux(8), firstboot(8), semanage(8), restorecon(8), chcon(1), sepol‐
188 icy(8), setsebool(8)
189firstboot 23-02-03 firstboot_selinux(8)