1postfix_smtp_selinux(8) SELinux Policy postfix_smtp postfix_smtp_selinux(8)
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6 postfix_smtp_selinux - Security Enhanced Linux Policy for the post‐
7 fix_smtp processes
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10 Security-Enhanced Linux secures the postfix_smtp processes via flexible
11 mandatory access control.
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13 The postfix_smtp processes execute with the postfix_smtp_t SELinux
14 type. You can check if you have these processes running by executing
15 the ps command with the -Z qualifier.
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17 For example:
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19 ps -eZ | grep postfix_smtp_t
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24 The postfix_smtp_t SELinux type can be entered via the post‐
25 fix_smtp_exec_t file type.
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27 The default entrypoint paths for the postfix_smtp_t domain are the fol‐
28 lowing:
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30 /usr/libexec/postfix/lmtp, /usr/libexec/postfix/smtp,
31 /usr/libexec/postfix/scache
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34 SELinux defines process types (domains) for each process running on the
35 system
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37 You can see the context of a process using the -Z option to ps
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39 Policy governs the access confined processes have to files. SELinux
40 postfix_smtp policy is very flexible allowing users to setup their
41 postfix_smtp processes in as secure a method as possible.
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43 The following process types are defined for postfix_smtp:
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45 postfix_smtp_t, postfix_smtpd_t
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47 Note: semanage permissive -a postfix_smtp_t can be used to make the
48 process type postfix_smtp_t permissive. SELinux does not deny access to
49 permissive process types, but the AVC (SELinux denials) messages are
50 still generated.
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54 SELinux policy is customizable based on least access required. post‐
55 fix_smtp policy is extremely flexible and has several booleans that
56 allow you to manipulate the policy and run postfix_smtp with the tight‐
57 est access possible.
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61 If you want to allow users to resolve user passwd entries directly from
62 ldap rather then using a sssd server, you must turn on the authlo‐
63 gin_nsswitch_use_ldap boolean. Disabled by default.
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65 setsebool -P authlogin_nsswitch_use_ldap 1
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69 If you want to deny any process from ptracing or debugging any other
70 processes, you must turn on the deny_ptrace boolean. Enabled by
71 default.
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73 setsebool -P deny_ptrace 1
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77 If you want to allow any process to mmap any file on system with
78 attribute file_type, you must turn on the domain_can_mmap_files bool‐
79 ean. Enabled by default.
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81 setsebool -P domain_can_mmap_files 1
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85 If you want to allow all domains write to kmsg_device, while kernel is
86 executed with systemd.log_target=kmsg parameter, you must turn on the
87 domain_can_write_kmsg boolean. Disabled by default.
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89 setsebool -P domain_can_write_kmsg 1
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93 If you want to allow all domains to use other domains file descriptors,
94 you must turn on the domain_fd_use boolean. Enabled by default.
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96 setsebool -P domain_fd_use 1
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100 If you want to allow all domains to have the kernel load modules, you
101 must turn on the domain_kernel_load_modules boolean. Disabled by
102 default.
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104 setsebool -P domain_kernel_load_modules 1
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108 If you want to allow all domains to execute in fips_mode, you must turn
109 on the fips_mode boolean. Enabled by default.
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111 setsebool -P fips_mode 1
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115 If you want to enable reading of urandom for all domains, you must turn
116 on the global_ssp boolean. Disabled by default.
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118 setsebool -P global_ssp 1
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122 If you want to allow confined applications to run with kerberos, you
123 must turn on the kerberos_enabled boolean. Enabled by default.
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125 setsebool -P kerberos_enabled 1
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129 If you want to allow system to run with NIS, you must turn on the
130 nis_enabled boolean. Disabled by default.
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132 setsebool -P nis_enabled 1
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136 If you want to allow confined applications to use nscd shared memory,
137 you must turn on the nscd_use_shm boolean. Disabled by default.
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139 setsebool -P nscd_use_shm 1
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144 The SELinux process type postfix_smtp_t can manage files labeled with
145 the following file types. The paths listed are the default paths for
146 these file types. Note the processes UID still need to have DAC per‐
147 missions.
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149 anon_inodefs_t
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152 postfix_prng_t
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154 /etc/postfix/prng_exch
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156 postfix_smtp_tmp_t
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159 postfix_spool_t
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161 /var/spool/postfix.*
162 /var/spool/postfix/defer(/.*)?
163 /var/spool/postfix/flush(/.*)?
164 /var/spool/postfix/deferred(/.*)?
165 /var/spool/postfix/maildrop(/.*)?
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167 postfix_var_run_t
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169 /var/spool/postfix/pid/.*
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173 SELinux requires files to have an extended attribute to define the file
174 type.
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176 You can see the context of a file using the -Z option to ls
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178 Policy governs the access confined processes have to these files.
179 SELinux postfix_smtp policy is very flexible allowing users to setup
180 their postfix_smtp processes in as secure a method as possible.
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182 STANDARD FILE CONTEXT
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184 SELinux defines the file context types for the postfix_smtp, if you
185 wanted to store files with these types in a diffent paths, you need to
186 execute the semanage command to sepecify alternate labeling and then
187 use restorecon to put the labels on disk.
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189 semanage fcontext -a -t postfix_smtpd_tmp_t '/srv/mypostfix_smtp_con‐
190 tent(/.*)?'
191 restorecon -R -v /srv/mypostfix_smtp_content
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193 Note: SELinux often uses regular expressions to specify labels that
194 match multiple files.
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196 The following file types are defined for postfix_smtp:
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200 postfix_smtp_exec_t
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202 - Set files with the postfix_smtp_exec_t type, if you want to transi‐
203 tion an executable to the postfix_smtp_t domain.
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206 Paths:
207 /usr/libexec/postfix/lmtp, /usr/libexec/postfix/smtp,
208 /usr/libexec/postfix/scache
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211 postfix_smtp_tmp_t
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213 - Set files with the postfix_smtp_tmp_t type, if you want to store
214 postfix smtp temporary files in the /tmp directories.
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218 postfix_smtpd_exec_t
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220 - Set files with the postfix_smtpd_exec_t type, if you want to transi‐
221 tion an executable to the postfix_smtpd_t domain.
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225 postfix_smtpd_tmp_t
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227 - Set files with the postfix_smtpd_tmp_t type, if you want to store
228 postfix smtpd temporary files in the /tmp directories.
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232 Note: File context can be temporarily modified with the chcon command.
233 If you want to permanently change the file context you need to use the
234 semanage fcontext command. This will modify the SELinux labeling data‐
235 base. You will need to use restorecon to apply the labels.
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239 semanage fcontext can also be used to manipulate default file context
240 mappings.
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242 semanage permissive can also be used to manipulate whether or not a
243 process type is permissive.
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245 semanage module can also be used to enable/disable/install/remove pol‐
246 icy modules.
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248 semanage boolean can also be used to manipulate the booleans
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251 system-config-selinux is a GUI tool available to customize SELinux pol‐
252 icy settings.
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256 This manual page was auto-generated using sepolicy manpage .
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260 selinux(8), postfix_smtp(8), semanage(8), restorecon(8), chcon(1),
261 sepolicy(8) , setsebool(8)
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265postfix_smtp 19-04-25 postfix_smtp_selinux(8)