inspec/docs/resources/file.md.erb
Michał Sochoń 7a935a204e Update file.md with example how to test symlinked files.
Added detailed example why and how.
Updated with suggestions from Adam Leff.

Signed-off-by: Michał Sochoń <kaszpir@gmail.com>
2017-03-15 07:53:14 +01:00

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---
title: About the file Resource
---
# file
Use the `file` InSpec audit resource to test all system file types, including files, directories, symbolic links, named pipes, sockets, character devices, block devices, and doors.
## Syntax
A `file` resource block declares the location of the file type to be tested, what type that file should be (if required), and then one (or more) matchers:
describe file('path') do
it { should MATCHER 'value' }
end
where
* `('path')` is the name of the file and/or the path to the file
* `MATCHER` is a valid matcher for this resource
* `'value'` is the value to be tested
## Matchers
This InSpec audit resource has the following matchers:
### be
<%= partial "/shared/matcher_be" %>
### be\_block\_device
The `be_block_device` matcher tests if the file exists as a block device, such as `/dev/disk0` or `/dev/disk0s9`:
it { should be_block_device }
### be\_character\_device
The `be_character_device` matcher tests if the file exists as a character device (that corresponds to a block device), such as `/dev/rdisk0` or `/dev/rdisk0s9`:
it { should be_character_device }
### be_directory
The `be_directory` matcher tests if the file exists as a directory, such as `/etc/passwd`, `/etc/shadow`, or `/var/log/httpd`:
it { should be_directory }
### be_executable
The `be_executable` matcher tests if the file exists as an executable:
it { should be_executable }
The `be_executable` matcher may also test if the file is executable by a specific owner, group, or user. For example, a group:
it { should be_executable.by('group') }
an owner:
it { should be_executable.by('owner') }
a user:
it { should be_executable.by_user('user') }
### be_file
The `be_file` matcher tests if the file exists as a file. This can be useful with configuration files like `/etc/passwd` where there typically is not an associated file extension---`passwd.txt`:
it { should be_file }
### be\_grouped\_into
The `be_grouped_into` matcher tests if the file exists as part of the named group:
it { should be_grouped_into 'group' }
### be_immutable
The `be_immutable` matcher tests if the file is immutable, i.e. "cannot be changed":
it { should be_immutable }
### be\_linked\_to
The `be_linked_to` matcher tests if the file is linked to the named target:
it { should be_linked_to '/etc/target-file' }
### be_mounted
The `be_mounted` matcher tests if the file is accessible from the file system:
it { should be_mounted }
### be\_owned\_by
The `be_owned_by` matcher tests if the file is owned by the named user, such as `root`:
it { should be_owned_by 'root' }
### be_pipe
The `be_pipe` matcher tests if the file exists as first-in, first-out special file (`.fifo`) that is typically used to define a named pipe, such as `/var/log/nginx/access.log.fifo`:
it { should be_pipe }
### be_readable
The `be_readable` matcher tests if the file is readable:
it { should be_readable }
The `be_readable` matcher may also test if the file is readable by a specific owner, group, or user. For example, a group:
it { should be_readable.by('group') }
an owner:
it { should be_readable.by('owner') }
a user:
it { should be_readable.by_user('user') }
### be_socket
The `be_socket` matcher tests if the file exists as socket (`.sock`), such as `/var/run/php-fpm.sock`:
it { should be_socket }
### be_symlink
The `be_symlink` matcher tests if the file exists as a symbolic, or soft link that contains an absolute or relative path reference to another file:
it { should be_symlink }
### be_version
The `be_version` matcher tests the version of the file:
it { should be_version '1.2.3' }
### be_writable
The `be_writable` matcher tests if the file is writable:
it { should be_writable }
The `be_writable` matcher may also test if the file is writable by a specific owner, group, or user. For example, a group:
it { should be_writable.by('group') }
an owner:
it { should be_writable.by('owner') }
a user:
it { should be_writable.by_user('user') }
### cmp
<%= partial "/shared/matcher_cmp" %>
### content
The `content` matcher tests if contents in the file match the value specified in a regular expression. The values of the `content` matcher are arbitrary and depend on the file type being tested and also the type of information that is expected to be in that file:
its('content') { should match REGEX }
The following complete example tests the `pg_hba.conf` file in PostgreSQL for MD5 requirements. The tests look at all `host` and `local` settings in that file, and then compare the MD5 checksums against the values in the test:
describe file(hba_config_file) do
its('content') { should match(%r{local\s.*?all\s.*?all\s.*?md5}) }
its('content') { should match(%r{host\s.*?all\s.*?all\s.*?127.0.0.1\/32\s.*?md5}) }
its('content') { should match(%r{host\s.*?all\s.*?all\s.*?::1\/128\s.*?md5})
end
### eq
<%= partial "/shared/matcher_eq" %>
### exist
The `exist` matcher tests if the named file exists:
it { should exist }
### file_version
The `file_version` matcher tests if the file's version matches the specified value. The difference between a file's "file version" and "product version" is that the file version is the version number of the file itself, whereas the product version is the version number associated with the application from which that file originates:
its('file_version') { should eq '1.2.3' }
### group
The `group` matcher tests if the group to which a file belongs matches the specified value:
its('group') { should eq 'admins' }
### have_mode
The `have_mode` matcher tests if a file has a mode assigned to it:
it { should have_mode }
### include
<%= partial "/shared/matcher_include" %>
### link_path
The `link_path` matcher tests if the file exists at the specified path:
its('link_path') { should eq '/some/path/to/file' }
### link_target
The `link_target` matcher tests if a file that is linked to this file exists at the specified path:
its('link_target') { should eq '/some/path/to/file' }
### match
<%= partial "/shared/matcher_match" %>
### md5sum
The `md5sum` matcher tests if the MD5 checksum for a file matches the specified value:
its('md5sum') { should eq '3329x3hf9130gjs9jlasf2305mx91s4j' }
### mode
The `mode` matcher tests if the mode assigned to the file matches the specified value:
its('mode') { should cmp '0644' }
### mtime
The `mtime` matcher tests if the file modification time for the file matches the specified value:
its('mtime') { should eq 'October 31 2015 12:10:45' }
or:
describe file('/').mtime.to_i do
it { should <= Time.now.to_i }
it { should >= Time.now.to_i - 1000}
end
### owner
The `owner` matcher tests if the owner of the file matches the specified value:
its('owner') { should eq 'root' }
### product_version
The `product_version` matcher tests if the file's product version matches the specified value. The difference between a file's "file version" and "product version" is that the file version is the version number of the file itself, whereas the product version is the version number associated with the application from which that file originates:
its('product_version') { should eq 2.3.4 }
### selinux_label
The `selinux_label` matcher tests if the SELinux label for a file matches the specified value:
its('selinux_label') { should eq 'system_u:system_r:httpd_t:s0' }
### sha256sum
The `sha256sum` matcher tests if the SHA-256 checksum for a file matches the specified value:
its('sha256sum') { should eq 'b837ch38lh19bb8eaopl8jvxwd2e4g58jn9lkho1w3ed9jbkeicalplaad9k0pjn' }
### size
The `size` matcher tests if a file's size matches, is greater than, or is less than the specified value. For example, equal:
its('size') { should eq 32375 }
Greater than:
its('size') { should > 64 }
Less than:
its('size') { should < 10240 }
### type
The `type` matcher tests if the first letter of the file's mode string contains one of the following characters:
* `-` or `f` (the file is a file); use `'file` to test for this file type
* `d` (the file is a directory); use `'directory` to test for this file type
* `l` (the file is a symbolic link); use `'link` to test for this file type
* `p` (the file is a named pipe); use `'pipe` to test for this file type
* `s` (the file is a socket); use `'socket` to test for this file type
* `c` (the file is a character device); use `'character` to test for this file type
* `b` (the file is a block device); use `'block` to test for this file type
* `D` (the file is a door); use `'door` to test for this file type
For example:
its('type') { should eq 'file' }
or:
its('type') { should eq 'socket' }
## Examples
The following examples show how to use this InSpec audit resource.
### Test the contents of a file for MD5 requirements
describe file(hba_config_file) do
its('content') { should match /local\s.*?all\s.*?all\s.*?md5/ }
its('content') { should match %r{/host\s.*?all\s.*?all\s.*?127.0.0.1\/32\s.*?md5/} }
its('content') { should match %r{/host\s.*?all\s.*?all\s.*?::1\/128\s.*?md5/} }
end
### Test if a file exists
describe file('/tmp') do
it { should exist }
end
### Test that a file does not exist
describe file('/tmpest') do
it { should_not exist }
end
### Test if a path is a directory
describe file('/tmp') do
its('type') { should eq :directory }
it { should be_directory }
end
### Test if a path is a file and not a directory
describe file('/proc/version') do
its('type') { should eq 'file' }
it { should be_file }
it { should_not be_directory }
end
### Test if a file is a symbolic link
describe file('/dev/stdout') do
its('type') { should eq 'symlink' }
it { should be_symlink }
it { should_not be_file }
it { should_not be_directory }
end
### Test if a file is a character device
describe file('/dev/zero') do
its('type') { should eq 'character' }
it { should be_character_device }
it { should_not be_file }
it { should_not be_directory }
end
### Test if a file is a block device
describe file('/dev/zero') do
its('type') { should eq 'block' }
it { should be_character_device }
it { should_not be_file }
it { should_not be_directory }
end
### Test the mode for a file
describe file('/dev') do
its('mode') { should cmp '00755' }
end
### Test the owner of a file
describe file('/root') do
its('owner') { should eq 'root' }
end
### Test if a file is owned by the root user
describe file('/dev') do
it { should be_owned_by 'root' }
end
### Test the mtime for a file
describe file('/').mtime.to_i do
it { should <= Time.now.to_i }
it { should >= Time.now.to_i - 1000}
end
### Test that a file's size is between 64 and 10240
describe file('/') do
its('size') { should be > 64 }
its('size') { should be < 10240 }
end
### Test that a file's size is zero
describe file('/proc/cpuinfo') do
its('size') { should be 0 }
end
### Test that a file is not mounted
describe file('/proc/cpuinfo') do
it { should_not be_mounted }
end
### Test an MD5 checksum
require 'digest'
cpuinfo = file('/proc/cpuinfo').content
md5sum = Digest::MD5.hexdigest(cpuinfo)
describe file('/proc/cpuinfo') do
its('md5sum') { should eq md5sum }
end
### Test an SHA-256 checksum
require 'digest'
cpuinfo = file('/proc/cpuinfo').content
sha256sum = Digest::SHA256.hexdigest(cpuinfo)
describe file('/proc/cpuinfo') do
its('sha256sum') { should eq sha256sum }
end
### Verify NTP
The following example shows how to use the `file` audit resource to verify if the `ntp.conf` and `leap-seconds` files are present, and then the `command` resource to verify if NTP is installed and running:
describe file('/etc/ntp.conf') do
it { should be_file }
end
describe file('/etc/ntp.leapseconds') do
it { should be_file }
end
describe command('pgrep ntp') do
its('exit_status') { should eq 0 }
end
### Test parameters of symlinked file
If you need to test the parameters of the target file for a symlink, you can use the `link_path` method for the `file` resource.
For example, for the following symlink:
lrwxrwxrwx. 1 root root 11 03-10 17:56 /dev/virtio-ports/com.redhat.rhevm.vdsm -> ../vport2p1
... you can write controls for both the link and the target.
describe file('/dev/virtio-ports/com.redhat.rhevm.vdsm') do
it { should be_symlink }
end
virito_port_vdsm = file('/dev/virtio-ports/com.redhat.rhevm.vdsm').link_path
describe file(virito_port_vdsm) do
it { should exist }
it { should be_character_device }
it { should be_owned_by 'ovirtagent' }
it { should be_grouped_into 'ovirtagent' }
end