doc/man3/SSL_CTX_load_verify_locations.pod - third_party/openssl - Git at Google

 =pod

 =head1 NAME

 SSL_CTX_load_verify_dir, SSL_CTX_load_verify_file,
 SSL_CTX_load_verify_store, SSL_CTX_set_default_verify_paths,
 SSL_CTX_set_default_verify_dir, SSL_CTX_set_default_verify_file,
 SSL_CTX_set_default_verify_store, SSL_CTX_load_verify_locations
 - set default locations for trusted CA certificates

 =head1 SYNOPSIS

  #include <openssl/ssl.h>

  int SSL_CTX_load_verify_dir(SSL_CTX *ctx, const char *CApath);
  int SSL_CTX_load_verify_file(SSL_CTX *ctx, const char *CAfile);
  int SSL_CTX_load_verify_store(SSL_CTX *ctx, const char *CAstore);

  int SSL_CTX_set_default_verify_paths(SSL_CTX *ctx);

  int SSL_CTX_set_default_verify_dir(SSL_CTX *ctx);
  int SSL_CTX_set_default_verify_file(SSL_CTX *ctx);
  int SSL_CTX_set_default_verify_store(SSL_CTX *ctx);

  int SSL_CTX_load_verify_locations(SSL_CTX *ctx, const char *CAfile,
                                    const char *CApath);

 =head1 DESCRIPTION

 SSL_CTX_load_verify_locations(), SSL_CTX_load_verify_dir(),
 SSL_CTX_load_verify_file(), SSL_CTX_load_verify_store() specifies the
 locations for B<ctx>, at which CA certificates for verification purposes
 are located. The certificates available via B<CAfile>, B<CApath> and
 B<CAstore> are trusted.

 Details of the certificate verification and chain checking process are
 described in L<openssl-verification-options(1)/Certification Path Validation>.

 SSL_CTX_set_default_verify_paths() specifies that the default locations from
 which CA certificates are loaded should be used. There is one default directory,
 one default file and one default store.
 The default CA certificates directory is called F<certs> in the default OpenSSL
 directory, and this is also the default store.
 Alternatively the B<SSL_CERT_DIR> environment variable can be defined to
 override this location.
 The default CA certificates file is called F<cert.pem> in the default
 OpenSSL directory.
 Alternatively the B<SSL_CERT_FILE> environment variable can be defined to
 override this location.

 SSL_CTX_set_default_verify_dir() is similar to
 SSL_CTX_set_default_verify_paths() except that just the default directory is
 used.

 SSL_CTX_set_default_verify_file() is similar to
 SSL_CTX_set_default_verify_paths() except that just the default file is
 used.

 SSL_CTX_set_default_verify_store() is similar to
 SSL_CTX_set_default_verify_paths() except that just the default store is
 used.

 =head1 NOTES

 If B<CAfile> is not NULL, it points to a file of CA certificates in PEM
 format. The file can contain several CA certificates identified by

  -----BEGIN CERTIFICATE-----
  ... (CA certificate in base64 encoding) ...
  -----END CERTIFICATE-----

 sequences. Before, between, and after the certificates text is allowed
 which can be used e.g. for descriptions of the certificates.

 The B<CAfile> is processed on execution of the SSL_CTX_load_verify_locations()
 function.

 If B<CApath> is not NULL, it points to a directory containing CA certificates
 in PEM format. The files each contain one CA certificate. The files are
 looked up by the CA subject name hash value, which must hence be available.
 If more than one CA certificate with the same name hash value exist, the
 extension must be different (e.g. 9d66eef0.0, 9d66eef0.1 etc). The search
 is performed in the ordering of the extension number, regardless of other
 properties of the certificates.
 Use the B<c_rehash> utility to create the necessary links.

 The certificates in B<CApath> are only looked up when required, e.g. when
 building the certificate chain or when actually performing the verification
 of a peer certificate.

 When looking up CA certificates for chain building, the OpenSSL library
 will search for suitable certificates first in B<CAfile>, then in B<CApath>.
 Details of the chain building process are described in
 L<openssl-verification-options(1)/Certification Path Building>.

 If B<CAstore> is not NULL, it's a URI for to a store, which may
 represent a single container or a whole catalogue of containers.
 Apart from the B<CAstore> not necessarily being a local file or
 directory, it's generally treated the same way as a B<CApath>.

 In server mode, when requesting a client certificate, the server must send
 the list of CAs of which it will accept client certificates. This list
 is not influenced by the contents of B<CAfile> or B<CApath> and must
 explicitly be set using the
 L<SSL_CTX_set_client_CA_list(3)>
 family of functions.

 When building its own certificate chain, an OpenSSL client/server will
 try to fill in missing certificates from B<CAfile>/B<CApath>, if the
 certificate chain was not explicitly specified (see
 L<SSL_CTX_add_extra_chain_cert(3)>,
 L<SSL_CTX_use_certificate(3)>.

 =head1 WARNINGS

 If several CA certificates matching the name, key identifier, and serial
 number condition are available, only the first one will be examined. This
 may lead to unexpected results if the same CA certificate is available
 with different expiration dates. If a "certificate expired" verification
 error occurs, no other certificate will be searched. Make sure to not
 have expired certificates mixed with valid ones.

 =head1 RETURN VALUES

 For SSL_CTX_load_verify_locations the following return values can occur:

 =over 4

 =item Z<>0

 The operation failed because B<CAfile> and B<CApath> are NULL or the
 processing at one of the locations specified failed. Check the error
 stack to find out the reason.

 =item Z<>1

 The operation succeeded.

 =back

 SSL_CTX_set_default_verify_paths(), SSL_CTX_set_default_verify_dir() and
 SSL_CTX_set_default_verify_file() all return 1 on success or 0 on failure. A
 missing default location is still treated as a success.

 =head1 EXAMPLES

 Generate a CA certificate file with descriptive text from the CA certificates
 ca1.pem ca2.pem ca3.pem:

  #!/bin/sh
  rm CAfile.pem
  for i in ca1.pem ca2.pem ca3.pem ; do
      openssl x509 -in $i -text >> CAfile.pem
  done

 Prepare the directory /some/where/certs containing several CA certificates
 for use as B<CApath>:

  cd /some/where/certs
  c_rehash .

 =head1 SEE ALSO

 L<ssl(7)>,
 L<SSL_CTX_set_client_CA_list(3)>,
 L<SSL_get_client_CA_list(3)>,
 L<SSL_CTX_use_certificate(3)>,
 L<SSL_CTX_add_extra_chain_cert(3)>,
 L<SSL_CTX_set_cert_store(3)>,
 L<SSL_CTX_set_client_CA_list(3)>

 =head1 COPYRIGHT

 Copyright 2000-2021 The OpenSSL Project Authors. All Rights Reserved.

 Licensed under the Apache License 2.0 (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

	SSL_CTX_load_verify_dir, SSL_CTX_load_verify_file,
	SSL_CTX_load_verify_store, SSL_CTX_set_default_verify_paths,
	SSL_CTX_set_default_verify_dir, SSL_CTX_set_default_verify_file,
	SSL_CTX_set_default_verify_store, SSL_CTX_load_verify_locations
	- set default locations for trusted CA certificates

	=head1 SYNOPSIS

	#include <openssl/ssl.h>

	int SSL_CTX_load_verify_dir(SSL_CTX ctx, const char CApath);
	int SSL_CTX_load_verify_file(SSL_CTX ctx, const char CAfile);
	int SSL_CTX_load_verify_store(SSL_CTX ctx, const char CAstore);

	int SSL_CTX_set_default_verify_paths(SSL_CTX *ctx);

	int SSL_CTX_set_default_verify_dir(SSL_CTX *ctx);
	int SSL_CTX_set_default_verify_file(SSL_CTX *ctx);
	int SSL_CTX_set_default_verify_store(SSL_CTX *ctx);

	int SSL_CTX_load_verify_locations(SSL_CTX ctx, const char CAfile,
	const char *CApath);

	=head1 DESCRIPTION

	SSL_CTX_load_verify_locations(), SSL_CTX_load_verify_dir(),
	SSL_CTX_load_verify_file(), SSL_CTX_load_verify_store() specifies the
	locations for B<ctx>, at which CA certificates for verification purposes
	are located. The certificates available via B<CAfile>, B<CApath> and
	B<CAstore> are trusted.

	Details of the certificate verification and chain checking process are
	described in L<openssl-verification-options(1)/Certification Path Validation>.

	SSL_CTX_set_default_verify_paths() specifies that the default locations from
	which CA certificates are loaded should be used. There is one default directory,
	one default file and one default store.
	The default CA certificates directory is called F<certs> in the default OpenSSL
	directory, and this is also the default store.
	Alternatively the B<SSL_CERT_DIR> environment variable can be defined to
	override this location.
	The default CA certificates file is called F<cert.pem> in the default
	OpenSSL directory.
	Alternatively the B<SSL_CERT_FILE> environment variable can be defined to
	override this location.

	SSL_CTX_set_default_verify_dir() is similar to
	SSL_CTX_set_default_verify_paths() except that just the default directory is
	used.

	SSL_CTX_set_default_verify_file() is similar to
	SSL_CTX_set_default_verify_paths() except that just the default file is
	used.

	SSL_CTX_set_default_verify_store() is similar to
	SSL_CTX_set_default_verify_paths() except that just the default store is
	used.

	=head1 NOTES

	If B<CAfile> is not NULL, it points to a file of CA certificates in PEM
	format. The file can contain several CA certificates identified by

	-----BEGIN CERTIFICATE-----
	... (CA certificate in base64 encoding) ...
	-----END CERTIFICATE-----

	sequences. Before, between, and after the certificates text is allowed
	which can be used e.g. for descriptions of the certificates.

	The B<CAfile> is processed on execution of the SSL_CTX_load_verify_locations()
	function.

	If B<CApath> is not NULL, it points to a directory containing CA certificates
	in PEM format. The files each contain one CA certificate. The files are
	looked up by the CA subject name hash value, which must hence be available.
	If more than one CA certificate with the same name hash value exist, the
	extension must be different (e.g. 9d66eef0.0, 9d66eef0.1 etc). The search
	is performed in the ordering of the extension number, regardless of other
	properties of the certificates.
	Use the B<c_rehash> utility to create the necessary links.

	The certificates in B<CApath> are only looked up when required, e.g. when
	building the certificate chain or when actually performing the verification
	of a peer certificate.

	When looking up CA certificates for chain building, the OpenSSL library
	will search for suitable certificates first in B<CAfile>, then in B<CApath>.
	Details of the chain building process are described in
	L<openssl-verification-options(1)/Certification Path Building>.

	If B<CAstore> is not NULL, it's a URI for to a store, which may
	represent a single container or a whole catalogue of containers.
	Apart from the B<CAstore> not necessarily being a local file or
	directory, it's generally treated the same way as a B<CApath>.

	In server mode, when requesting a client certificate, the server must send
	the list of CAs of which it will accept client certificates. This list
	is not influenced by the contents of B<CAfile> or B<CApath> and must
	explicitly be set using the
	L<SSL_CTX_set_client_CA_list(3)>
	family of functions.

	When building its own certificate chain, an OpenSSL client/server will
	try to fill in missing certificates from B<CAfile>/B<CApath>, if the
	certificate chain was not explicitly specified (see
	L<SSL_CTX_add_extra_chain_cert(3)>,
	L<SSL_CTX_use_certificate(3)>.

	=head1 WARNINGS

	If several CA certificates matching the name, key identifier, and serial
	number condition are available, only the first one will be examined. This
	may lead to unexpected results if the same CA certificate is available
	with different expiration dates. If a "certificate expired" verification
	error occurs, no other certificate will be searched. Make sure to not
	have expired certificates mixed with valid ones.

	=head1 RETURN VALUES

	For SSL_CTX_load_verify_locations the following return values can occur:

	=over 4

	=item Z<>0

	The operation failed because B<CAfile> and B<CApath> are NULL or the
	processing at one of the locations specified failed. Check the error
	stack to find out the reason.

	=item Z<>1

	The operation succeeded.

	=back

	SSL_CTX_set_default_verify_paths(), SSL_CTX_set_default_verify_dir() and
	SSL_CTX_set_default_verify_file() all return 1 on success or 0 on failure. A
	missing default location is still treated as a success.

	=head1 EXAMPLES

	Generate a CA certificate file with descriptive text from the CA certificates
	ca1.pem ca2.pem ca3.pem:

	#!/bin/sh
	rm CAfile.pem
	for i in ca1.pem ca2.pem ca3.pem ; do
	openssl x509 -in $i -text >> CAfile.pem
	done

	Prepare the directory /some/where/certs containing several CA certificates
	for use as B<CApath>:

	cd /some/where/certs
	c_rehash .

	=head1 SEE ALSO

	L<ssl(7)>,
	L<SSL_CTX_set_client_CA_list(3)>,
	L<SSL_get_client_CA_list(3)>,
	L<SSL_CTX_use_certificate(3)>,
	L<SSL_CTX_add_extra_chain_cert(3)>,
	L<SSL_CTX_set_cert_store(3)>,
	L<SSL_CTX_set_client_CA_list(3)>

	=head1 COPYRIGHT

	Copyright 2000-2021 The OpenSSL Project Authors. All Rights Reserved.

	Licensed under the Apache License 2.0 (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