1postfix_smtpd_selinux(8) SELinux Policy postfix_smtpd postfix_smtpd_selinux(8)
2
6 postfix_smtpd_selinux - Security Enhanced Linux Policy for the post‐
7 fix_smtpd processes
8
10 Security-Enhanced Linux secures the postfix_smtpd processes via flexi‐
11 ble mandatory access control.
12 The postfix_smtpd processes execute with the postfix_smtpd_t SELinux
14 type. You can check if you have these processes running by executing
15 the ps command with the -Z qualifier.
16 For example:
18 ps -eZ | grep postfix_smtpd_t
20
24 The postfix_smtpd_t SELinux type can be entered via the post‐
25 fix_smtpd_exec_t file type.
26 The default entrypoint paths for the postfix_smtpd_t domain are the
28 following:
29 /usr/libexec/postfix/smtpd
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 postfix_smtpd policy is very flexible allowing users to setup their
40 postfix_smtpd processes in as secure a method as possible.
41 The following process types are defined for postfix_smtpd:
43 postfix_smtp_t, postfix_smtpd_t
45 Note: semanage permissive -a postfix_smtpd_t can be used to make the
47 process type postfix_smtpd_t permissive. SELinux does not deny access
48 to permissive process types, but the AVC (SELinux denials) messages are
49 still generated.
50
53 SELinux policy is customizable based on least access required. post‐
54 fix_smtpd policy is extremely flexible and has several booleans that
55 allow you to manipulate the policy and run postfix_smtpd with the
56 tightest access possible.
57 If you want to allow users to resolve user passwd entries directly from
61 ldap rather then using a sssd server, you must turn on the authlo‐
62 gin_nsswitch_use_ldap boolean. Disabled by default.
63 setsebool -P authlogin_nsswitch_use_ldap 1
65 If you want to allow all domains to execute in fips_mode, you must turn
69 on the fips_mode boolean. Enabled by default.
70 setsebool -P fips_mode 1
72 If you want to allow confined applications to run with kerberos, you
76 must turn on the kerberos_enabled boolean. Enabled by default.
77 setsebool -P kerberos_enabled 1
79 If you want to allow system to run with NIS, you must turn on the
83 nis_enabled boolean. Disabled by default.
84 setsebool -P nis_enabled 1
86 If you want to allow confined applications to use nscd shared memory,
90 you must turn on the nscd_use_shm boolean. Disabled by default.
91 setsebool -P nscd_use_shm 1
93
97 The SELinux process type postfix_smtpd_t can manage files labeled with
98 the following file types. The paths listed are the default paths for
99 these file types. Note the processes UID still need to have DAC per‐
100 missions.
101 anon_inodefs_t
103 postfix_prng_t
106 /etc/postfix/prng_exch
108 postfix_smtpd_tmp_t
110 postfix_spool_t
113 /var/spool/postfix.*
115 /var/spool/postfix/defer(/.*)?
116 /var/spool/postfix/flush(/.*)?
117 /var/spool/postfix/deferred(/.*)?
118 /var/spool/postfix/maildrop(/.*)?
119 postfix_var_run_t
121 /var/spool/postfix/pid/.*
123
126 SELinux requires files to have an extended attribute to define the file
127 type.
128 You can see the context of a file using the -Z option to ls
130 Policy governs the access confined processes have to these files.
132 SELinux postfix_smtpd policy is very flexible allowing users to setup
133 their postfix_smtpd processes in as secure a method as possible.
134 STANDARD FILE CONTEXT
136 SELinux defines the file context types for the postfix_smtpd, if you
138 wanted to store files with these types in a diffent paths, you need to
139 execute the semanage command to sepecify alternate labeling and then
140 use restorecon to put the labels on disk.
141 semanage fcontext -a -t postfix_smtpd_tmp_t '/srv/mypostfix_smtpd_con‐
143 tent(/.*)?'
144 restorecon -R -v /srv/mypostfix_smtpd_content
145 Note: SELinux often uses regular expressions to specify labels that
147 match multiple files.
148 The following file types are defined for postfix_smtpd:
150 postfix_smtpd_exec_t
154 - Set files with the postfix_smtpd_exec_t type, if you want to transi‐
156 tion an executable to the postfix_smtpd_t domain.
157 postfix_smtpd_tmp_t
161 - Set files with the postfix_smtpd_tmp_t type, if you want to store
163 postfix smtpd temporary files in the /tmp directories.
164 Note: File context can be temporarily modified with the chcon command.
168 If you want to permanently change the file context you need to use the
169 semanage fcontext command. This will modify the SELinux labeling data‐
170 base. You will need to use restorecon to apply the labels.
171
174 semanage fcontext can also be used to manipulate default file context
175 mappings.
176 semanage permissive can also be used to manipulate whether or not a
178 process type is permissive.
179 semanage module can also be used to enable/disable/install/remove pol‐
181 icy modules.
182 semanage boolean can also be used to manipulate the booleans
184 system-config-selinux is a GUI tool available to customize SELinux pol‐
187 icy settings.
188
191 This manual page was auto-generated using sepolicy manpage .
192
195 selinux(8), postfix_smtpd(8), semanage(8), restorecon(8), chcon(1),
196 sepolicy(8), setsebool(8)
197postfix_smtpd 19-06-18 postfix_smtpd_selinux(8)