1AUDIT2ALLOW(1) NSA AUDIT2ALLOW(1)
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6 audit2allow - generate SELinux policy allow/dontaudit rules from logs
7 of denied operations
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9 audit2why - translates SELinux audit messages into a description of why
10 the access was denied (audit2allow -w)
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14 audit2allow [options]
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17 -a | --all
18 Read input from audit and message log, conflicts with -i
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20 -b | --boot
21 Read input from audit messages since last boot, conflicts with
22 -i
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24 -d | --dmesg
25 Read input from output of /bin/dmesg. Note that all audit mes‐
26 sages are not available via dmesg when auditd is running; use
27 "ausearch -m avc | audit2allow" or "-a" instead.
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29 -D | --dontaudit
30 Generate dontaudit rules (Default: allow)
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32 -e | --explain
33 Fully explain generated output
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35 -h | --help
36 Print a short usage message
37
38 -i <inputfile> | --input <inputfile>
39 Read input from <inputfile>
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41 --interface-info=<interface_info_file>
42 Read interface information from <interface_info_file>
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44 -l | --lastreload
45 Read input only after last policy reload
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47 -m <modulename> | --module <modulename>
48 Generate module/require output <modulename>
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50 -M <modulename>
51 Generate loadable module package, conflicts with -o
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53 -p <policyfile> | --policy <policyfile>
54 Policy file to use for analysis
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56 --perm-map <perm_map_file>
57 Read permission map from <perm_map_file>
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59 -o <outputfile> | --output <outputfile>
60 Append output to <outputfile>
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62 -r | --requires
63 Generate require output syntax for loadable modules.
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65 -N | --noreference
66 Do not generate reference policy, traditional style allow rules.
67 This is the default behavior.
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69 -R | --reference
70 Generate reference policy using installed macros. This attempts
71 to match denials against interfaces and may be inaccurate.
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73 -t <type_regex> | --type=<type_regex>
74 Only process messages with a type that matches this regex
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76 -x | --xperms
77 Generate extended permission access vector rules
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79 -w | --why
80 Translates SELinux audit messages into a description of why the
81 access was denied
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84 -v | --verbose
85 Turn on verbose output
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89 This utility scans the logs for messages logged when the system denied
90 permission for operations, and generates a snippet of policy rules
91 which, if loaded into policy, might have allowed those operations to
92 succeed. However, this utility only generates Type Enforcement (TE) al‐
93 low rules. Certain permission denials may require other kinds of pol‐
94 icy changes, e.g. adding an attribute to a type declaration to satisfy
95 an existing constraint, adding a role allow rule, or modifying a con‐
96 straint. The audit2why(8) utility may be used to diagnose the reason
97 when it is unclear.
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99 Care must be exercised while acting on the output of this utility to
100 ensure that the operations being permitted do not pose a security
101 threat. Often it is better to define new domains and/or types, or make
102 other structural changes to narrowly allow an optimal set of operations
103 to succeed, as opposed to blindly implementing the sometimes broad
104 changes recommended by this utility. Certain permission denials are
105 not fatal to the application, in which case it may be preferable to
106 simply suppress logging of the denial via a 'dontaudit' rule rather
107 than an 'allow' rule.
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110 NOTE: These examples are for systems using the audit package. If you do
111 not use the audit package, the AVC messages will be in /var/log/messages.
112 Please substitute /var/log/messages for /var/log/audit/audit.log in the
113 examples.
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115 Using audit2allow to generate module policy
116
117 $ cat /var/log/audit/audit.log | audit2allow -m local > local.te
118 $ cat local.te
119 module local 1.0;
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121 require {
122 class file { getattr open read };
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124
125 type myapp_t;
126 type etc_t;
127 };
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130 allow myapp_t etc_t:file { getattr open read };
131 <review local.te and customize as desired>
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133 Using audit2allow to generate module policy using reference policy
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135 $ cat /var/log/audit/audit.log | audit2allow -R -m local > local.te
136 $ cat local.te
137 policy_module(local, 1.0)
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139 gen_require(`
140 type myapp_t;
141 type etc_t;
142 ')
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144 files_read_etc_files(myapp_t)
145 <review local.te and customize as desired>
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147 Building module policy using Makefile
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149 # SELinux provides a policy devel environment under
150 # /usr/share/selinux/devel including all of the shipped
151 # interface files.
152 # You can create a te file and compile it by executing
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154 $ make -f /usr/share/selinux/devel/Makefile local.pp
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157 # This make command will compile a local.te file in the current
158 # directory. If you did not specify a "pp" file, the make file
159 # will compile all "te" files in the current directory. After
160 # you compile your te file into a "pp" file, you need to install
161 # it using the semodule command.
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163 $ semodule -i local.pp
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165 Building module policy manually
166
167 # Compile the module
168 $ checkmodule -M -m -o local.mod local.te
169
170 # Create the package
171 $ semodule_package -o local.pp -m local.mod
172
173 # Load the module into the kernel
174 $ semodule -i local.pp
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176 Using audit2allow to generate and build module policy
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178 $ cat /var/log/audit/audit.log | audit2allow -M local
179 Generating type enforcement file: local.te
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181 Compiling policy: checkmodule -M -m -o local.mod local.te
182 Building package: semodule_package -o local.pp -m local.mod
183
184 ******************** IMPORTANT ***********************
185
186 In order to load this newly created policy package into the kernel,
187 you are required to execute
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189 semodule -i local.pp
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191 Using audit2allow to generate monolithic (non-module) policy
192
193 $ cd /etc/selinux/$SELINUXTYPE/src/policy
194 $ cat /var/log/audit/audit.log | audit2allow >> domains/misc/local.te
195 $ cat domains/misc/local.te
196 allow cupsd_config_t unconfined_t:fifo_file { getattr ioctl };
197 <review domains/misc/local.te and customize as desired>
198 $ make load
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202 This manual page was written by Manoj Srivastava <srivasta@debian.org>,
203 for the Debian GNU/Linux system. It was updated by Dan Walsh
204 <dwalsh@redhat.com>
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206 The audit2allow utility has contributions from several people, includ‐
207 ing Justin R. Smith and Yuichi Nakamura. and Dan Walsh
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211Security Enhanced Linux October 2010 AUDIT2ALLOW(1)