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file resource

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Use the file Chef InSpec audit resource to test all system file types, including files, directories, symbolic links, named pipes, sockets, character devices, block devices, and doors.

Availability

Installation

This resource is distributed along with Chef InSpec itself. You can use it automatically.

Version

This resource first became available in v1.0.0 of InSpec.

Syntax

A file resource block declares the location of the file type to be tested, the expected file type (if required), and one (or more) resource properties.

describe file('path') do
  it { should PROPERTY 'value' }
end

where

  • ('path') is the name of the file and/or the path to the file.
  • PROPERTY is a valid resource property for this resource'
  • 'value' is the value to be tested.

Properties

General Properties

  • content
  • size
  • basename
  • path
  • owner
  • group
  • type

Unix/Linux Properties

  • symlink
  • mode
  • link_path
  • shallow_link_path
  • mtime
  • size
  • selinux_label
  • md5sum
  • sha256sum
  • path
  • source
  • source_path
  • uid
  • gid

Windows Properties

  • file_version
  • product_version

Resource Property Examples

content

The content property tests if contents in the file match the value specified in a regular expression. The values of the content property 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('/etc/postgresql/9.1/main/pg_hba.conf') 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

file_version

The file_version property tests if a Windows 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 property tests if the group to which a file belongs matches the specified value.

its('group') { should eq 'admins' }

The following examples show how to use this Chef InSpec audit resource.

The link_path property tests if the file exists at the specified path. If the file is a symlink, Chef InSpec will resolve the symlink recursively and return the ultimate linked file.

its('link_path') { should eq '/some/path/to/file' }

The shallow_link_path property returns the path that the file refers to, only resolving it once (that is, it performs a readlink operation). If the file is not a symlink, nil is returned.

its('shallow_link_path') { should eq '/some/path/to/file' }

md5sum

The md5sum property tests if the MD5 checksum for a file matches the specified value.

its('md5sum') { should eq '3329x3hf9130gjs9jlasf2305mx91s4j' }

mode

The mode property tests if the mode assigned to the file matches the specified value.

its('mode') { should cmp '0644' }

Chef InSpec octal values begin the numeric mode specification with zero.

For example, write:

{ should cmp '0644' }

not

{ should cmp '644' }

or write:

{ should cmp '01775' }

not

{ should cmp '1775' }

Without the zero prefix for the octal value, Chef InSpec will interpret it as the decimal value 644, which is octal 1024 or -----w-r-T, and any test for a file that is -rw-r--r-- will fail.

Note: see the be_more_permissive_than(mode) matcher for upper and lower bounds on file mode.

mtime

The mtime property tests if the file modification time for the file matches the specified value. The mtime, where supported, is returned as the number of seconds since the epoch.

describe file('/') do
  its('mtime') { should <= Time.now.to_i }
  its('mtime') { should >= Time.now.to_i - 1000 }
end

owner

The owner property tests if the owner of the file matches the specified value.

its('owner') { should eq 'root' }

product_version

The product_version property tests if a Windows 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 property 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 property tests if the SHA-256 checksum for a file matches the specified value.

its('sha256sum') { should eq 'b837ch38lh19bb8eaopl8jvxwd2e4g58jn9lkho1w3ed9jbkeicalplaad9k0pjn' }

size

The size property 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 property tests for the file type. The available types are:

file
the object is a file
directory
the object is a directory
link
the object is a symbolic link
pipe
the object is a named pipe
socket
the object is a socket
character_device
the object is a character device
block_device
the object is a block device
door
the object is a door device

The type method usually returns the type as a Ruby “symbol”. We recommend using the cmp matcher to match either by symbol or string.

For example:

its('type') { should eq :file }
its('type') { should cmp 'file' }

or:

its('type') { should eq :socket }
its('type') { should cmp 'socket' }

Test the contents of a file for MD5 requirements

describe file('/etc/postgresql/9.1/main/pg_hba.conf') 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 cmp 'file' }
  it { should be_file }
  it { should_not be_directory }
end

describe file('/dev/stdout') do
  its('type') { should cmp '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 cmp '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 cmp '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('/') do
  its('mtime') { should <= Time.now.to_i }
  its('mtime') { 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 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 (recursive resolution) or shallow_link_path (direct link) 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

Matchers

For a full list of available matchers, please visit our matchers page.

be_allowed

The be_allowed matcher tests if the file contains a certain permission set, such as execute or write in Unix and full-control or modify in Windows.

it { should be_allowed('read') }

Just like with be_executable and other permissions, one can check for the permission with respect to the specific user or group.

it { should be_allowed('full-control', by_user: 'MyComputerName\Administrator') }

OR

it { should be_allowed('write', by: 'root') }

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') }

any user other than the owner or members of the file’s group:

it { should be_executable.by('others') }

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_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_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') }

any user other than the owner or members of the file’s group:

it { should be_readable.by('others') }

a user:

it { should be_readable.by_user('user') }

be_setgid

The be_setgid matcher tests if the ‘setgid’ permission is set on the file or directory. On executable files, this causes the process to be started owned by the group that owns the file, rather than the primary group of the invocating user. This can result in escalation of privilege. On Linux, when setgid is set on directories, setgid causes newly created files and directories to be owned by the group that owns the setgid parent directory; additionally, newly created subdirectories will have the setgid bit set. To use this matcher:

it { should be_setgid }

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_sticky

The be_sticky matcher tests if the ‘sticky bit’ permission is set on the directory. On directories, this restricts file deletion to the owner of the file, even if the permission of the parent directory would normally permit deletion by others. This is commonly used on /tmp filesystems. To use this matcher:

it { should be_sticky }

be_setuid

The be_setuid matcher tests if the ‘setuid’ permission is set on the file. On executable files, this causes the process to be started owned by the user that owns the file, rather than invocating user. This can result in escalation of privilege. To use this matcher:

it { should be_setuid }

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') }

any user other than the owner or members of the file’s group:

it { should be_writable.by('others') }

a user:

it { should be_writable.by_user('user') }

exist

The exist matcher tests if the named file exists:

it { should exist }

have_mode

The have_mode matcher tests if a file has a mode assigned to it:

it { should have_mode }

be_more_permissive_than(mode)

be_more_permissive_than(mode) takes the maximum desired mode - in octal format (‘0644’ or ‘0777’) - of your file as a String and returns a Boolean. It will return true if your file has a mode with greater permissions than specified.

describe file('/etc/passwd') do
  it { should_not be_more_permissive_than('0644') }
  it { should be_more_permissive_than('0000') }
end

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