1AUDIT2ALLOW(1) NSA AUDIT2ALLOW(1)
2
6 audit2allow - generate SELinux policy allow/dontaudit rules from logs
7 of denied operations
8 audit2why - translates SELinux audit messages into a description of why
10 the access was denied (audit2allow -w)
11
14 audit2allow [options]
15
17 -a | --all
18 Read input from audit and message log, conflicts with -i
19 -b | --boot
21 Read input from audit messages since last boot conflicts with -i
22 -d | --dmesg
24 Read input from output of /bin/dmesg. Note that all audit mes‐
25 sages are not available via dmesg when auditd is running; use
26 "ausearch -m avc | audit2allow" or "-a" instead.
27 -D | --dontaudit
29 Generate dontaudit rules (Default: allow)
30 -h | --help
32 Print a short usage message
33 -i <inputfile> | --input <inputfile>
35 read input from <inputfile>
36 -l | --lastreload
38 read input only after last policy reload
39 -m <modulename> | --module <modulename>
41 Generate module/require output <modulename>
42 -M <modulename>
44 Generate loadable module package, conflicts with -o
45 -p <policyfile> | --policy <policyfile>
47 Policy file to use for analysis
48 -o <outputfile> | --output <outputfile>
50 append output to <outputfile>
51 -r | --requires
53 Generate require output syntax for loadable modules.
54 -N | --noreference
56 Do not generate reference policy, traditional style allow rules.
57 This is the default behavior.
58 -R | --reference
60 Generate reference policy using installed macros. This attempts
61 to match denials against interfaces and may be inaccurate.
62 -w | --why
64 Translates SELinux audit messages into a description of why the
65 access was denied
66 -v | --verbose
69 Turn on verbose output
70
73 This utility scans the logs for messages logged when the system denied
74 permission for operations, and generates a snippet of policy rules
75 which, if loaded into policy, might have allowed those operations to
76 succeed. However, this utility only generates Type Enforcement (TE)
77 allow rules. Certain permission denials may require other kinds of
78 policy changes, e.g. adding an attribute to a type declaration to sat‐
79 isfy an existing constraint, adding a role allow rule, or modifying a
80 constraint. The audit2why(8) utility may be used to diagnose the rea‐
81 son when it is unclear.
82 Care must be exercised while acting on the output of this utility to
84 ensure that the operations being permitted do not pose a security
85 threat. Often it is better to define new domains and/or types, or make
86 other structural changes to narrowly allow an optimal set of operations
87 to succeed, as opposed to blindly implementing the sometimes broad
88 changes recommended by this utility. Certain permission denials are
89 not fatal to the application, in which case it may be preferable to
90 simply suppress logging of the denial via a 'dontaudit' rule rather
91 than an 'allow' rule.
92
94 NOTE: These examples are for systems using the audit package. If you do
95 not use the audit package, the AVC messages will be in /var/log/messages.
96 Please substitute /var/log/messages for /var/log/audit/audit.log in the
97 examples.
98 Using audit2allow to generate module policy
100 $ cat /var/log/audit/audit.log | audit2allow -m local > local.te
102 $ cat local.te
103 module local 1.0;
104 require {
106 class file { getattr open read };
107 type myapp_t;
110 type etc_t;
111 };
112 allow myapp_t etc_t:file { getattr open read };
115 <review local.te and customize as desired>
116 Using audit2allow to generate module policy using reference policy
118 $ cat /var/log/audit/audit.log | audit2allow -R -m local > local.te
120 $ cat local.te
121 policy_module(local, 1.0)
122 gen_require(`
124 type myapp_t;
125 type etc_t;
126 };
127 files_read_etc_files(myapp_t)
129 <review local.te and customize as desired>
130 Building module policy using Makefile
132 # SELinux provides a policy devel environment under /usr/share/selinux/devel
134 # You can create a te file and compile it by executing
135 $ make -f /usr/share/selinux/devel/Makefile
136 $ semodule -i local.pp
137 Building module policy manually
139 # Compile the module
141 $ checkmodule -M -m -o local.mod local.te
142 # Create the package
143 $ semodule_package -o local.pp -m local.mod
144 # Load the module into the kernel
145 $ semodule -i local.pp
146 Using audit2allow to generate and build module policy
148 $ cat /var/log/audit/audit.log | audit2allow -M local
149 Generating type enforcment file: local.te
150 Compiling policy: checkmodule -M -m -o local.mod local.te
151 Building package: semodule_package -o local.pp -m local.mod
152 ******************** IMPORTANT ***********************
154 In order to load this newly created policy package into the kernel,
156 you are required to execute
157 semodule -i local.pp
159 Using audit2allow to generate monolithic (non-module) policy
161 $ cd /etc/selinux/$SELINUXTYPE/src/policy
162 $ cat /var/log/audit/audit.log | audit2allow >> domains/misc/local.te
163 $ cat domains/misc/local.te
164 allow cupsd_config_t unconfined_t:fifo_file { getattr ioctl };
165 <review domains/misc/local.te and customize as desired>
166 $ make load
167
170 This manual page was written by Manoj Srivastava <srivasta@debian.org>,
171 for the Debian GNU/Linux system. It was updated by Dan Walsh
172 <dwalsh@redhat.com>
173 The audit2allow utility has contributions from several people, includ‐
175 ing Justin R. Smith and Yuichi Nakamura. and Dan Walsh
176Security Enhanced Linux October 2010 AUDIT2ALLOW(1)