1sandbox_selinux(8) SELinux Policy sandbox sandbox_selinux(8)
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6 sandbox_selinux - Security Enhanced Linux Policy for the sandbox pro‐
7 cesses
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10 Security-Enhanced Linux secures the sandbox processes via flexible
11 mandatory access control.
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13 The sandbox processes execute with the sandbox_t SELinux type. You can
14 check if you have these processes running by executing the ps command
15 with the -Z qualifier.
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17 For example:
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19 ps -eZ | grep sandbox_t
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24 The sandbox_t SELinux type can be entered via the file_type file type.
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26 The default entrypoint paths for the sandbox_t domain are the follow‐
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29 all files on the system
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32 SELinux defines process types (domains) for each process running on the
33 system
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35 You can see the context of a process using the -Z option to ps
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37 Policy governs the access confined processes have to files. SELinux
38 sandbox policy is very flexible allowing users to setup their sandbox
39 processes in as secure a method as possible.
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41 The following process types are defined for sandbox:
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43 sandbox_t, sandbox_xserver_t, sandbox_min_t, sandbox_min_client_t, sandbox_x_t, sandbox_x_client_t, sandbox_web_t, sandbox_web_client_t, sandbox_net_t, sandbox_net_client_t
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45 Note: semanage permissive -a sandbox_t can be used to make the process
46 type sandbox_t permissive. SELinux does not deny access to permissive
47 process types, but the AVC (SELinux denials) messages are still gener‐
48 ated.
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52 The SELinux process type sandbox_t is an MCS (Multi Category Security)
53 constrained type. Sometimes this separation is referred to as sVirt.
54 These types are usually used for securing multi-tenant environments,
55 such as virtualization, containers or separation of users. The tools
56 used to launch MCS types, pick out a different MCS label for each
57 process group.
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59 For example one process might be launched with sandbox_t:s0:c1,c2, and
60 another process launched with sandbox_t:s0:c3,c4. The SELinux kernel
61 only allows these processes can only write to content with a matching
62 MCS label, or a MCS Label of s0. A process running with the MCS level
63 of s0:c1,c2 is not allowed to write to content with the MCS label of
64 s0:c3,c4
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68 SELinux policy is customizable based on least access required. sandbox
69 policy is extremely flexible and has several booleans that allow you to
70 manipulate the policy and run sandbox with the tightest access possi‐
71 ble.
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75 If you want to deny user domains applications to map a memory region as
76 both executable and writable, this is dangerous and the executable
77 should be reported in bugzilla, you must turn on the deny_execmem bool‐
78 ean. Enabled by default.
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80 setsebool -P deny_execmem 1
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84 If you want to deny any process from ptracing or debugging any other
85 processes, you must turn on the deny_ptrace boolean. Enabled by
86 default.
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88 setsebool -P deny_ptrace 1
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92 If you want to allow any process to mmap any file on system with
93 attribute file_type, you must turn on the domain_can_mmap_files bool‐
94 ean. Enabled by default.
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96 setsebool -P domain_can_mmap_files 1
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100 If you want to allow all domains write to kmsg_device, while kernel is
101 executed with systemd.log_target=kmsg parameter, you must turn on the
102 domain_can_write_kmsg boolean. Disabled by default.
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104 setsebool -P domain_can_write_kmsg 1
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108 If you want to allow all domains to use other domains file descriptors,
109 you must turn on the domain_fd_use boolean. Enabled by default.
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111 setsebool -P domain_fd_use 1
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115 If you want to allow all domains to have the kernel load modules, you
116 must turn on the domain_kernel_load_modules boolean. Disabled by
117 default.
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119 setsebool -P domain_kernel_load_modules 1
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123 If you want to allow all domains to execute in fips_mode, you must turn
124 on the fips_mode boolean. Enabled by default.
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126 setsebool -P fips_mode 1
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130 If you want to enable reading of urandom for all domains, you must turn
131 on the global_ssp boolean. Disabled by default.
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133 setsebool -P global_ssp 1
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138 The SELinux process type sandbox_t can manage files labeled with the
139 following file types. The paths listed are the default paths for these
140 file types. Note the processes UID still need to have DAC permissions.
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142 sandbox_file_t
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145 sandbox_tmpfs_type
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147 all sandbox content in tmpfs file systems
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151 SELinux requires files to have an extended attribute to define the file
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154 You can see the context of a file using the -Z option to ls
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156 Policy governs the access confined processes have to these files.
157 SELinux sandbox policy is very flexible allowing users to setup their
158 sandbox processes in as secure a method as possible.
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160 STANDARD FILE CONTEXT
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162 SELinux defines the file context types for the sandbox, if you wanted
163 to store files with these types in a diffent paths, you need to execute
164 the semanage command to sepecify alternate labeling and then use
165 restorecon to put the labels on disk.
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167 semanage fcontext -a -t sandbox_xserver_tmpfs_t '/srv/mysandbox_con‐
168 tent(/.*)?'
169 restorecon -R -v /srv/mysandbox_content
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171 Note: SELinux often uses regular expressions to specify labels that
172 match multiple files.
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174 The following file types are defined for sandbox:
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178 sandbox_devpts_t
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180 - Set files with the sandbox_devpts_t type, if you want to treat the
181 files as sandbox devpts data.
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185 sandbox_exec_t
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187 - Set files with the sandbox_exec_t type, if you want to transition an
188 executable to the sandbox_t domain.
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192 sandbox_file_t
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194 - Set files with the sandbox_file_t type, if you want to treat the
195 files as sandbox content.
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199 sandbox_min_client_tmpfs_t
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201 - Set files with the sandbox_min_client_tmpfs_t type, if you want to
202 store sandbox min client files on a tmpfs file system.
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206 sandbox_net_client_tmpfs_t
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208 - Set files with the sandbox_net_client_tmpfs_t type, if you want to
209 store sandbox net client files on a tmpfs file system.
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213 sandbox_web_client_tmpfs_t
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215 - Set files with the sandbox_web_client_tmpfs_t type, if you want to
216 store sandbox web client files on a tmpfs file system.
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220 sandbox_x_client_tmpfs_t
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222 - Set files with the sandbox_x_client_tmpfs_t type, if you want to
223 store sandbox x client files on a tmpfs file system.
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227 sandbox_xserver_tmpfs_t
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229 - Set files with the sandbox_xserver_tmpfs_t type, if you want to store
230 sandbox xserver files on a tmpfs file system.
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234 Note: File context can be temporarily modified with the chcon command.
235 If you want to permanently change the file context you need to use the
236 semanage fcontext command. This will modify the SELinux labeling data‐
237 base. You will need to use restorecon to apply the labels.
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241 semanage fcontext can also be used to manipulate default file context
242 mappings.
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244 semanage permissive can also be used to manipulate whether or not a
245 process type is permissive.
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247 semanage module can also be used to enable/disable/install/remove pol‐
248 icy modules.
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250 semanage boolean can also be used to manipulate the booleans
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253 system-config-selinux is a GUI tool available to customize SELinux pol‐
254 icy settings.
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258 This manual page was auto-generated using sepolicy manpage .
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262 selinux(8), sandbox(8), semanage(8), restorecon(8), chcon(1), sepol‐
263 icy(8) , setsebool(8), sandbox_min_selinux(8), sandbox_min_selinux(8),
264 sandbox_min_client_selinux(8), sandbox_min_client_selinux(8), sand‐
265 box_net_selinux(8), sandbox_net_selinux(8), sand‐
266 box_net_client_selinux(8), sandbox_net_client_selinux(8), sand‐
267 box_web_selinux(8), sandbox_web_selinux(8), sand‐
268 box_web_client_selinux(8), sandbox_web_client_selinux(8), sand‐
269 box_x_selinux(8), sandbox_x_selinux(8), sandbox_x_client_selinux(8),
270 sandbox_x_client_selinux(8), sandbox_xserver_selinux(8), sand‐
271 box_xserver_selinux(8)
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275sandbox 19-04-25 sandbox_selinux(8)