doc/man5/config.pod - third_party/openssl - Git at Google

 =pod

 =head1 NAME

 config - OpenSSL CONF library configuration files

 =head1 DESCRIPTION

 The OpenSSL CONF library can be used to read configuration files.
 It is used for the OpenSSL master configuration file B<openssl.cnf>
 and in a few other places like B<SPKAC> files and certificate extension
 files for the B<x509> utility. OpenSSL applications can also use the
 CONF library for their own purposes.

 A configuration file is divided into a number of sections. Each section
 starts with a line B<[ section_name ]> and ends when a new section is
 started or end of file is reached. A section name can consist of
 alphanumeric characters and underscores.

 The first section of a configuration file is special and is referred
 to as the B<default> section this is usually unnamed and is from the
 start of file until the first named section. When a name is being looked up
 it is first looked up in a named section (if any) and then the
 default section.

 The environment is mapped onto a section called B<ENV>.

 Comments can be included by preceding them with the B<#> character

 Each section in a configuration file consists of a number of name and
 value pairs of the form B<name=value>

 The B<name> string can contain any alphanumeric characters as well as
 a few punctuation symbols such as B<.> B<,> B<;> and B<_>.

 The B<value> string consists of the string following the B<=> character
 until end of line with any leading and trailing white space removed.

 The value string undergoes variable expansion. This can be done by
 including the form B<$var> or B<${var}>: this will substitute the value
 of the named variable in the current section. It is also possible to
 substitute a value from another section using the syntax B<$section::name>
 or B<${section::name}>. By using the form B<$ENV::name> environment
 variables can be substituted. It is also possible to assign values to
 environment variables by using the name B<ENV::name>, this will work
 if the program looks up environment variables using the B<CONF> library
 instead of calling getenv() directly.

 It is possible to escape certain characters by using any kind of quote
 or the B<\> character. By making the last character of a line a B<\>
 a B<value> string can be spread across multiple lines. In addition
 the sequences B<\n>, B<\r>, B<\b> and B<\t> are recognized.

 =head1 OPENSSL LIBRARY CONFIGURATION

 Applications can automatically configure certain
 aspects of OpenSSL using the master OpenSSL configuration file, or optionally
 an alternative configuration file. The B<openssl> utility includes this
 functionality: any sub command uses the master OpenSSL configuration file
 unless an option is used in the sub command to use an alternative configuration
 file.

 To enable library configuration the default section needs to contain an
 appropriate line which points to the main configuration section. The default
 name is B<openssl_conf> which is used by the B<openssl> utility. Other
 applications may use an alternative name such as B<myapplicaton_conf>.

 The configuration section should consist of a set of name value pairs which
 contain specific module configuration information. The B<name> represents
 the name of the I<configuration module> the meaning of the B<value> is
 module specific: it may, for example, represent a further configuration
 section containing configuration module specific information. E.g.

  openssl_conf = openssl_init

  [openssl_init]

  oid_section = new_oids
  engines = engine_section

  [new_oids]

  ... new oids here ...

  [engine_section]

  ... engine stuff here ...

 The features of each configuration module are described below.

 =head2 ASN1 Object Configuration Module

 This module has the name B<oid_section>. The value of this variable points
 to a section containing name value pairs of OIDs: the name is the OID short
 and long name, the value is the numerical form of the OID. Although some of
 the B<openssl> utility sub commands already have their own ASN1 OBJECT section
 functionality not all do. By using the ASN1 OBJECT configuration module
 B<all> the B<openssl> utility sub commands can see the new objects as well
 as any compliant applications. For example:

  [new_oids]

  some_new_oid = 1.2.3.4
  some_other_oid = 1.2.3.5

 It is also possible to set the value to the long name followed
 by a comma and the numerical OID form. For example:

  shortName = some object long name, 1.2.3.4

 =head2 Engine Configuration Module

 This ENGINE configuration module has the name B<engines>. The value of this
 variable points to a section containing further ENGINE configuration
 information.

 The section pointed to by B<engines> is a table of engine names (though see
 B<engine_id> below) and further sections containing configuration information
 specific to each ENGINE.

 Each ENGINE specific section is used to set default algorithms, load
 dynamic, perform initialization and send ctrls. The actual operation performed
 depends on the I<command> name which is the name of the name value pair. The
 currently supported commands are listed below.

 For example:

  [engine_section]

  # Configure ENGINE named "foo"
  foo = foo_section
  # Configure ENGINE named "bar"
  bar = bar_section

  [foo_section]
  ... foo ENGINE specific commands ...

  [bar_section]
  ... "bar" ENGINE specific commands ...

 The command B<engine_id> is used to give the ENGINE name. If used this
 command must be first. For example:

  [engine_section]
  # This would normally handle an ENGINE named "foo"
  foo = foo_section

  [foo_section]
  # Override default name and use "myfoo" instead.
  engine_id = myfoo

 The command B<dynamic_path> loads and adds an ENGINE from the given path. It
 is equivalent to sending the ctrls B<SO_PATH> with the path argument followed
 by B<LIST_ADD> with value 2 and B<LOAD> to the dynamic ENGINE. If this is
 not the required behaviour then alternative ctrls can be sent directly
 to the dynamic ENGINE using ctrl commands.

 The command B<init> determines whether to initialize the ENGINE. If the value
 is B<0> the ENGINE will not be initialized, if B<1> and attempt it made to
 initialized the ENGINE immediately. If the B<init> command is not present
 then an attempt will be made to initialize the ENGINE after all commands in
 its section have been processed.

 The command B<default_algorithms> sets the default algorithms an ENGINE will
 supply using the functions ENGINE_set_default_string().

 If the name matches none of the above command names it is assumed to be a
 ctrl command which is sent to the ENGINE. The value of the command is the
 argument to the ctrl command. If the value is the string B<EMPTY> then no
 value is sent to the command.

 For example:


  [engine_section]

  # Configure ENGINE named "foo"
  foo = foo_section

  [foo_section]
  # Load engine from DSO
  dynamic_path = /some/path/fooengine.so
  # A foo specific ctrl.
  some_ctrl = some_value
  # Another ctrl that doesn't take a value.
  other_ctrl = EMPTY
  # Supply all default algorithms
  default_algorithms = ALL

 =head2 EVP Configuration Module

 This modules has the name B<alg_section> which points to a section containing
 algorithm commands.

 Currently the only algorithm command supported is B<fips_mode> whose
 value should be a boolean string such as B<on> or B<off>. If the value is
 B<on> this attempt to enter FIPS mode. If the call fails or the library is
 not FIPS capable then an error occurs.

 For example:

  alg_section = evp_settings

  [evp_settings]

  fips_mode = on

 =head2 SSL Configuration Module

 This module has the name B<ssl_conf> which points to a section containing
 SSL configurations.

 Each line in the SSL configuration section contains the name of the
 configuration and the section containing it.

 Each configuration section consists of command value pairs for B<SSL_CONF>.
 Each pair will be passed to a B<SSL_CTX> or B<SSL> structure if it calls
 SSL_CTX_config() or SSL_config() with the appropriate configuration name.

 Note: any characters before an initial dot in the configuration section are
 ignored so the same command can be used multiple times.

 For example:

  ssl_conf = ssl_sect

  [ssl_sect]

  server = server_section

  [server_section]

  RSA.Certificate = server-rsa.pem
  ECDSA.Certificate = server-ecdsa.pem
  Ciphers = ALL:!RC4

 =head1 NOTES

 If a configuration file attempts to expand a variable that doesn't exist
 then an error is flagged and the file will not load. This can happen
 if an attempt is made to expand an environment variable that doesn't
 exist. For example in a previous version of OpenSSL the default OpenSSL
 master configuration file used the value of B<HOME> which may not be
 defined on non Unix systems and would cause an error.

 This can be worked around by including a B<default> section to provide
 a default value: then if the environment lookup fails the default value
 will be used instead. For this to work properly the default value must
 be defined earlier in the configuration file than the expansion. See
 the B<EXAMPLES> section for an example of how to do this.

 If the same variable exists in the same section then all but the last
 value will be silently ignored. In certain circumstances such as with
 DNs the same field may occur multiple times. This is usually worked
 around by ignoring any characters before an initial B<.> e.g.

  1.OU="My first OU"
  2.OU="My Second OU"

 =head1 EXAMPLES

 Here is a sample configuration file using some of the features
 mentioned above.

  # This is the default section.

  HOME=/temp
  RANDFILE= ${ENV::HOME}/.rnd
  configdir=$ENV::HOME/config

  [ section_one ]

  # We are now in section one.

  # Quotes permit leading and trailing whitespace
  any = " any variable name "

  other = A string that can \
  cover several lines \
  by including \\ characters

  message = Hello World\n

  [ section_two ]

  greeting = $section_one::message

 This next example shows how to expand environment variables safely.

 Suppose you want a variable called B<tmpfile> to refer to a
 temporary filename. The directory it is placed in can determined by
 the B<TEMP> or B<TMP> environment variables but they may not be
 set to any value at all. If you just include the environment variable
 names and the variable doesn't exist then this will cause an error when
 an attempt is made to load the configuration file. By making use of the
 default section both values can be looked up with B<TEMP> taking
 priority and B</tmp> used if neither is defined:

  TMP=/tmp
  # The above value is used if TMP isn't in the environment
  TEMP=$ENV::TMP
  # The above value is used if TEMP isn't in the environment
  tmpfile=${ENV::TEMP}/tmp.filename

 Simple OpenSSL library configuration example to enter FIPS mode:

  # Default appname: should match "appname" parameter (if any)
  # supplied to CONF_modules_load_file et al.
  openssl_conf = openssl_conf_section

  [openssl_conf_section]
  # Configuration module list
  alg_section = evp_sect

  [evp_sect]
  # Set to "yes" to enter FIPS mode if supported
  fips_mode = yes

 Note: in the above example you will get an error in non FIPS capable versions
 of OpenSSL.

 More complex OpenSSL library configuration. Add OID and don't enter FIPS mode:

  # Default appname: should match "appname" parameter (if any)
  # supplied to CONF_modules_load_file et al.
  openssl_conf = openssl_conf_section

  [openssl_conf_section]
  # Configuration module list
  alg_section = evp_sect
  oid_section = new_oids

  [evp_sect]
  # This will have no effect as FIPS mode is off by default.
  # Set to "yes" to enter FIPS mode, if supported
  fips_mode = no

  [new_oids]
  # New OID, just short name
  newoid1 = 1.2.3.4.1
  # New OID shortname and long name
  newoid2 = New OID 2 long name, 1.2.3.4.2

 The above examples can be used with any application supporting library
 configuration if "openssl_conf" is modified to match the appropriate "appname".

 For example if the second sample file above is saved to "example.cnf" then
 the command line:

  OPENSSL_CONF=example.cnf openssl asn1parse -genstr OID:1.2.3.4.1

 will output:

     0:d=0  hl=2 l=   4 prim: OBJECT            :newoid1

 showing that the OID "newoid1" has been added as "1.2.3.4.1".

 =head1 BUGS

 Currently there is no way to include characters using the octal B<\nnn>
 form. Strings are all null terminated so nulls cannot form part of
 the value.

 The escaping isn't quite right: if you want to use sequences like B<\n>
 you can't use any quote escaping on the same line.

 Files are loaded in a single pass. This means that an variable expansion
 will only work if the variables referenced are defined earlier in the
 file.

 =head1 SEE ALSO

 L<x509(1)>, L<req(1)>, L<ca(1)>

 =head1 COPYRIGHT

 Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.

 Licensed under the OpenSSL license (the "License").  You may not use
 this file except in compliance with the License.  You can obtain a copy
 in the file LICENSE in the source distribution or at
 L<https://www.openssl.org/source/license.html>.

 =cut
	=pod

	=head1 NAME

	config - OpenSSL CONF library configuration files

	=head1 DESCRIPTION

	The OpenSSL CONF library can be used to read configuration files.
	It is used for the OpenSSL master configuration file B<openssl.cnf>
	and in a few other places like B<SPKAC> files and certificate extension
	files for the B<x509> utility. OpenSSL applications can also use the
	CONF library for their own purposes.

	A configuration file is divided into a number of sections. Each section
	starts with a line B<[ section_name ]> and ends when a new section is
	started or end of file is reached. A section name can consist of
	alphanumeric characters and underscores.

	The first section of a configuration file is special and is referred
	to as the B<default> section this is usually unnamed and is from the
	start of file until the first named section. When a name is being looked up
	it is first looked up in a named section (if any) and then the
	default section.

	The environment is mapped onto a section called B<ENV>.

	Comments can be included by preceding them with the B<#> character

	Each section in a configuration file consists of a number of name and
	value pairs of the form B<name=value>

	The B<name> string can contain any alphanumeric characters as well as
	a few punctuation symbols such as B<.> B<,> B<;> and B<_>.

	The B<value> string consists of the string following the B<=> character
	until end of line with any leading and trailing white space removed.

	The value string undergoes variable expansion. This can be done by
	including the form B<$var> or B<${var}>: this will substitute the value
	of the named variable in the current section. It is also possible to
	substitute a value from another section using the syntax B<$section::name>
	or B<${section::name}>. By using the form B<$ENV::name> environment
	variables can be substituted. It is also possible to assign values to
	environment variables by using the name B<ENV::name>, this will work
	if the program looks up environment variables using the B<CONF> library
	instead of calling getenv() directly.

	It is possible to escape certain characters by using any kind of quote
	or the B<\> character. By making the last character of a line a B<\>
	a B<value> string can be spread across multiple lines. In addition
	the sequences B<\n>, B<\r>, B<\b> and B<\t> are recognized.

	=head1 OPENSSL LIBRARY CONFIGURATION

	Applications can automatically configure certain
	aspects of OpenSSL using the master OpenSSL configuration file, or optionally
	an alternative configuration file. The B<openssl> utility includes this
	functionality: any sub command uses the master OpenSSL configuration file
	unless an option is used in the sub command to use an alternative configuration
	file.

	To enable library configuration the default section needs to contain an
	appropriate line which points to the main configuration section. The default
	name is B<openssl_conf> which is used by the B<openssl> utility. Other
	applications may use an alternative name such as B<myapplicaton_conf>.

	The configuration section should consist of a set of name value pairs which
	contain specific module configuration information. The B<name> represents
	the name of the I<configuration module> the meaning of the B<value> is
	module specific: it may, for example, represent a further configuration
	section containing configuration module specific information. E.g.

	openssl_conf = openssl_init

	[openssl_init]

	oid_section = new_oids
	engines = engine_section

	[new_oids]

	... new oids here ...

	[engine_section]

	... engine stuff here ...

	The features of each configuration module are described below.

	=head2 ASN1 Object Configuration Module

	This module has the name B<oid_section>. The value of this variable points
	to a section containing name value pairs of OIDs: the name is the OID short
	and long name, the value is the numerical form of the OID. Although some of
	the B<openssl> utility sub commands already have their own ASN1 OBJECT section
	functionality not all do. By using the ASN1 OBJECT configuration module
	B<all> the B<openssl> utility sub commands can see the new objects as well
	as any compliant applications. For example:

	[new_oids]

	some_new_oid = 1.2.3.4
	some_other_oid = 1.2.3.5

	It is also possible to set the value to the long name followed
	by a comma and the numerical OID form. For example:

	shortName = some object long name, 1.2.3.4

	=head2 Engine Configuration Module

	This ENGINE configuration module has the name B<engines>. The value of this
	variable points to a section containing further ENGINE configuration
	information.

	The section pointed to by B<engines> is a table of engine names (though see
	B<engine_id> below) and further sections containing configuration information
	specific to each ENGINE.

	Each ENGINE specific section is used to set default algorithms, load
	dynamic, perform initialization and send ctrls. The actual operation performed
	depends on the I<command> name which is the name of the name value pair. The
	currently supported commands are listed below.

	For example:

	[engine_section]

	# Configure ENGINE named "foo"
	foo = foo_section
	# Configure ENGINE named "bar"
	bar = bar_section

	[foo_section]
	... foo ENGINE specific commands ...

	[bar_section]
	... "bar" ENGINE specific commands ...

	The command B<engine_id> is used to give the ENGINE name. If used this
	command must be first. For example:

	[engine_section]
	# This would normally handle an ENGINE named "foo"
	foo = foo_section

	[foo_section]
	# Override default name and use "myfoo" instead.
	engine_id = myfoo

	The command B<dynamic_path> loads and adds an ENGINE from the given path. It
	is equivalent to sending the ctrls B<SO_PATH> with the path argument followed
	by B<LIST_ADD> with value 2 and B<LOAD> to the dynamic ENGINE. If this is
	not the required behaviour then alternative ctrls can be sent directly
	to the dynamic ENGINE using ctrl commands.

	The command B<init> determines whether to initialize the ENGINE. If the value
	is B<0> the ENGINE will not be initialized, if B<1> and attempt it made to
	initialized the ENGINE immediately. If the B<init> command is not present
	then an attempt will be made to initialize the ENGINE after all commands in
	its section have been processed.

	The command B<default_algorithms> sets the default algorithms an ENGINE will
	supply using the functions ENGINE_set_default_string().

	If the name matches none of the above command names it is assumed to be a
	ctrl command which is sent to the ENGINE. The value of the command is the
	argument to the ctrl command. If the value is the string B<EMPTY> then no
	value is sent to the command.

	For example:


	[engine_section]

	# Configure ENGINE named "foo"
	foo = foo_section

	[foo_section]
	# Load engine from DSO
	dynamic_path = /some/path/fooengine.so
	# A foo specific ctrl.
	some_ctrl = some_value
	# Another ctrl that doesn't take a value.
	other_ctrl = EMPTY
	# Supply all default algorithms
	default_algorithms = ALL

	=head2 EVP Configuration Module

	This modules has the name B<alg_section> which points to a section containing
	algorithm commands.

	Currently the only algorithm command supported is B<fips_mode> whose
	value should be a boolean string such as B<on> or B<off>. If the value is
	B<on> this attempt to enter FIPS mode. If the call fails or the library is
	not FIPS capable then an error occurs.

	For example:

	alg_section = evp_settings

	[evp_settings]

	fips_mode = on

	=head2 SSL Configuration Module

	This module has the name B<ssl_conf> which points to a section containing
	SSL configurations.

	Each line in the SSL configuration section contains the name of the
	configuration and the section containing it.

	Each configuration section consists of command value pairs for B<SSL_CONF>.
	Each pair will be passed to a B<SSL_CTX> or B<SSL> structure if it calls
	SSL_CTX_config() or SSL_config() with the appropriate configuration name.

	Note: any characters before an initial dot in the configuration section are
	ignored so the same command can be used multiple times.

	For example:

	ssl_conf = ssl_sect

	[ssl_sect]

	server = server_section

	[server_section]

	RSA.Certificate = server-rsa.pem
	ECDSA.Certificate = server-ecdsa.pem
	Ciphers = ALL:!RC4

	=head1 NOTES

	If a configuration file attempts to expand a variable that doesn't exist
	then an error is flagged and the file will not load. This can happen
	if an attempt is made to expand an environment variable that doesn't
	exist. For example in a previous version of OpenSSL the default OpenSSL
	master configuration file used the value of B<HOME> which may not be
	defined on non Unix systems and would cause an error.

	This can be worked around by including a B<default> section to provide
	a default value: then if the environment lookup fails the default value
	will be used instead. For this to work properly the default value must
	be defined earlier in the configuration file than the expansion. See
	the B<EXAMPLES> section for an example of how to do this.

	If the same variable exists in the same section then all but the last
	value will be silently ignored. In certain circumstances such as with
	DNs the same field may occur multiple times. This is usually worked
	around by ignoring any characters before an initial B<.> e.g.

	1.OU="My first OU"
	2.OU="My Second OU"

	=head1 EXAMPLES

	Here is a sample configuration file using some of the features
	mentioned above.

	# This is the default section.

	HOME=/temp
	RANDFILE= ${ENV::HOME}/.rnd
	configdir=$ENV::HOME/config

	[ section_one ]

	# We are now in section one.

	# Quotes permit leading and trailing whitespace
	any = " any variable name "

	other = A string that can \
	cover several lines \
	by including \\ characters

	message = Hello World\n

	[ section_two ]

	greeting = $section_one::message

	This next example shows how to expand environment variables safely.

	Suppose you want a variable called B<tmpfile> to refer to a
	temporary filename. The directory it is placed in can determined by
	the B<TEMP> or B<TMP> environment variables but they may not be
	set to any value at all. If you just include the environment variable
	names and the variable doesn't exist then this will cause an error when
	an attempt is made to load the configuration file. By making use of the
	default section both values can be looked up with B<TEMP> taking
	priority and B</tmp> used if neither is defined:

	TMP=/tmp
	# The above value is used if TMP isn't in the environment
	TEMP=$ENV::TMP
	# The above value is used if TEMP isn't in the environment
	tmpfile=${ENV::TEMP}/tmp.filename

	Simple OpenSSL library configuration example to enter FIPS mode:

	# Default appname: should match "appname" parameter (if any)
	# supplied to CONF_modules_load_file et al.
	openssl_conf = openssl_conf_section

	[openssl_conf_section]
	# Configuration module list
	alg_section = evp_sect

	[evp_sect]
	# Set to "yes" to enter FIPS mode if supported
	fips_mode = yes

	Note: in the above example you will get an error in non FIPS capable versions
	of OpenSSL.

	More complex OpenSSL library configuration. Add OID and don't enter FIPS mode:

	# Default appname: should match "appname" parameter (if any)
	# supplied to CONF_modules_load_file et al.
	openssl_conf = openssl_conf_section

	[openssl_conf_section]
	# Configuration module list
	alg_section = evp_sect
	oid_section = new_oids

	[evp_sect]
	# This will have no effect as FIPS mode is off by default.
	# Set to "yes" to enter FIPS mode, if supported
	fips_mode = no

	[new_oids]
	# New OID, just short name
	newoid1 = 1.2.3.4.1
	# New OID shortname and long name
	newoid2 = New OID 2 long name, 1.2.3.4.2

	The above examples can be used with any application supporting library
	configuration if "openssl_conf" is modified to match the appropriate "appname".

	For example if the second sample file above is saved to "example.cnf" then
	the command line:

	OPENSSL_CONF=example.cnf openssl asn1parse -genstr OID:1.2.3.4.1

	will output:

	0:d=0 hl=2 l= 4 prim: OBJECT :newoid1

	showing that the OID "newoid1" has been added as "1.2.3.4.1".

	=head1 BUGS

	Currently there is no way to include characters using the octal B<\nnn>
	form. Strings are all null terminated so nulls cannot form part of
	the value.

	The escaping isn't quite right: if you want to use sequences like B<\n>
	you can't use any quote escaping on the same line.

	Files are loaded in a single pass. This means that an variable expansion
	will only work if the variables referenced are defined earlier in the
	file.

	=head1 SEE ALSO

	L<x509(1)>, L<req(1)>, L<ca(1)>

	=head1 COPYRIGHT

	Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.

	Licensed under the OpenSSL license (the "License"). You may not use
	this file except in compliance with the License. You can obtain a copy
	in the file LICENSE in the source distribution or at
	L<https://www.openssl.org/source/license.html>.

	=cut