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CA(1)				    OpenSSL				 CA(1)

       openssl-ca, ca -	sample minimal CA application

       openssl ca [-help] [-verbose] [-config filename]	[-name section]
       [-gencrl] [-revoke file]	[-valid	file] [-status serial] [-updatedb]
       [-crl_reason reason] [-crl_hold instruction] [-crl_compromise time]
       [-crl_CA_compromise time] [-crldays days] [-crlhours hours] [-crlexts
       section]	[-startdate date] [-enddate date] [-days arg] [-md arg]
       [-policy	arg] [-keyfile arg] [-keyform PEM|DER] [-key arg] [-passin
       arg] [-cert file] [-selfsign] [-in file]	[-out file] [-notext] [-outdir
       dir] [-infiles] [-spkac file] [-ss_cert file] [-preserveDN]
       [-noemailDN] [-batch] [-msie_hack] [-extensions section]	[-extfile
       section]	[-engine id] [-subj arg] [-utf8] [-sigopt nm:v]
       [-create_serial]	[-rand_serial] [-multivalue-rdn] [-rand	file...]
       [-writerand file]

       The ca command is a minimal CA application. It can be used to sign
       certificate requests in a variety of forms and generate CRLs it also
       maintains a text	database of issued certificates	and their status.

       The options descriptions	will be	divided	into each purpose.

	   Print out a usage message.

	   This	prints extra details about the operations being	performed.

       -config filename
	   Specifies the configuration file to use.  Optional; for a
	   description of the default value, see "COMMAND SUMMARY" in

       -name section
	   Specifies the configuration file section to use (overrides
	   default_ca in the ca	section).

       -in filename
	   An input filename containing	a single certificate request to	be
	   signed by the CA.

       -ss_cert	filename
	   A single self-signed	certificate to be signed by the	CA.

       -spkac filename
	   A file containing a single Netscape signed public key and challenge
	   and additional field	values to be signed by the CA. See the SPKAC
	   FORMAT section for information on the required input	and output

	   If present this should be the last option, all subsequent arguments
	   are taken as	the names of files containing certificate requests.

       -out filename
	   The output file to output certificates to. The default is standard
	   output. The certificate details will	also be	printed	out to this
	   file	in PEM format (except that -spkac outputs DER format).

       -outdir directory
	   The directory to output certificates	to. The	certificate will be
	   written to a	filename consisting of the serial number in hex	with
	   ".pem" appended.

	   The CA certificate file.

       -keyfile	filename
	   The private key to sign requests with.

       -keyform	PEM|DER
	   The format of the data in the private key file.  The	default	is

       -sigopt nm:v
	   Pass	options	to the signature algorithm during sign or verify
	   operations.	Names and values of these options are algorithm-

       -key password
	   The password	used to	encrypt	the private key. Since on some systems
	   the command line arguments are visible (e.g.	Unix with the 'ps'
	   utility) this option	should be used with caution.

	   Indicates the issued	certificates are to be signed with the key the
	   certificate requests	were signed with (given	with -keyfile).
	   Certificate requests	signed with a different	key are	ignored.  If
	   -spkac, -ss_cert or -gencrl are given, -selfsign is ignored.

	   A consequence of using -selfsign is that the	self-signed
	   certificate appears among the entries in the	certificate database
	   (see	the configuration option database), and	uses the same serial
	   number counter as all other certificates sign with the self-signed

       -passin arg
	   The key password source. For	more information about the format of
	   arg see "Pass Phrase	Options" in openssl(1).

	   Don't output	the text form of a certificate to the output file.

       -startdate date
	   This	allows the start date to be explicitly set. The	format of the
	   date	is YYMMDDHHMMSSZ (the same as an ASN1 UTCTime structure), or
	   YYYYMMDDHHMMSSZ (the	same as	an ASN1	GeneralizedTime	structure). In
	   both	formats, seconds SS and	timezone Z must	be present.

       -enddate	date
	   This	allows the expiry date to be explicitly	set. The format	of the
	   date	is YYMMDDHHMMSSZ (the same as an ASN1 UTCTime structure), or
	   YYYYMMDDHHMMSSZ (the	same as	an ASN1	GeneralizedTime	structure). In
	   both	formats, seconds SS and	timezone Z must	be present.

       -days arg
	   The number of days to certify the certificate for.

       -md alg
	   The message digest to use.  Any digest supported by the OpenSSL
	   dgst	command	can be used. For signing algorithms that do not
	   support a digest (i.e. Ed25519 and Ed448) any message digest	that
	   is set is ignored. This option also applies to CRLs.

       -policy arg
	   This	option defines the CA "policy" to use. This is a section in
	   the configuration file which	decides	which fields should be
	   mandatory or	match the CA certificate. Check	out the	POLICY FORMAT
	   section for more information.

	   This	is a deprecated	option to make ca work with very old versions
	   of the IE certificate enrollment control "certenr3".	It used
	   UniversalStrings for	almost everything. Since the old control has
	   various security bugs its use is strongly discouraged.

	   Normally the	DN order of a certificate is the same as the order of
	   the fields in the relevant policy section. When this	option is set
	   the order is	the same as the	request. This is largely for
	   compatibility with the older	IE enrollment control which would only
	   accept certificates if their	DNs match the order of the request.
	   This	is not needed for Xenroll.

	   The DN of a certificate can contain the EMAIL field if present in
	   the request DN, however, it is good policy just having the e-mail
	   set into the	altName	extension of the certificate. When this	option
	   is set the EMAIL field is removed from the certificate' subject and
	   set only in the, eventually present,	extensions. The	email_in_dn
	   keyword can be used in the configuration file to enable this

	   This	sets the batch mode. In	this mode no questions will be asked
	   and all certificates	will be	certified automatically.

       -extensions section
	   The section of the configuration file containing certificate
	   extensions to be added when a certificate is	issued (defaults to
	   x509_extensions unless the -extfile option is used).	If no
	   extension section is	present	then, a	V1 certificate is created. If
	   the extension section is present (even if it	is empty), then	a V3
	   certificate is created. See the x509v3_config(5) manual page	for
	   details of the extension section format.

       -extfile	file
	   An additional configuration file to read certificate	extensions
	   from	(using the default section unless the -extensions option is
	   also	used).

       -engine id
	   Specifying an engine	(by its	unique id string) will cause ca	to
	   attempt to obtain a functional reference to the specified engine,
	   thus	initialising it	if needed. The engine will then	be set as the
	   default for all available algorithms.

       -subj arg
	   Supersedes subject name given in the	request.  The arg must be
	   formatted as	/type0=value0/type1=value1/type2=....  Keyword
	   characters may be escaped by	\ (backslash), and whitespace is
	   retained.  Empty values are permitted, but the corresponding	type
	   will	not be included	in the resulting certificate.

	   This	option causes field values to be interpreted as	UTF8 strings,
	   by default they are interpreted as ASCII. This means	that the field
	   values, whether prompted from a terminal or obtained	from a
	   configuration file, must be valid UTF8 strings.

	   If reading serial from the text file	as specified in	the
	   configuration fails,	specifying this	option creates a new random
	   serial to be	used as	next serial number.  To	get random serial
	   numbers, use	the -rand_serial flag instead; this should only	be
	   used	for simple error-recovery.

	   Generate a large random number to use as the	serial number.	This
	   overrides any option	or configuration to use	a serial number	file.

	   This	option causes the -subj	argument to be interpreted with	full
	   support for multivalued RDNs. Example:

	   /DC=org/DC=OpenSSL/DC=users/UID=123456+CN=John Doe

	   If -multi-rdn is not	used then the UID value	is 123456+CN=John Doe.

       -rand file...
	   A file or files containing random data used to seed the random
	   number generator.  Multiple files can be specified separated	by an
	   OS-dependent	character.  The	separator is ; for MS-Windows, , for
	   OpenVMS, and	: for all others.

       [-writerand file]
	   Writes random data to the specified file upon exit.	This can be
	   used	with a subsequent -rand	flag.

	   This	option generates a CRL based on	information in the index file.

       -crldays	num
	   The number of days before the next CRL is due. That is the days
	   from	now to place in	the CRL	nextUpdate field.

       -crlhours num
	   The number of hours before the next CRL is due.

       -revoke filename
	   A filename containing a certificate to revoke.

       -valid filename
	   A filename containing a certificate to add a	Valid certificate

       -status serial
	   Displays the	revocation status of the certificate with the
	   specified serial number and exits.

	   Updates the database	index to purge expired certificates.

       -crl_reason reason
	   Revocation reason, where reason is one of: unspecified,
	   keyCompromise, CACompromise,	affiliationChanged, superseded,
	   cessationOfOperation, certificateHold or removeFromCRL. The
	   matching of reason is case insensitive. Setting any revocation
	   reason will make the	CRL v2.

	   In practice removeFromCRL is	not particularly useful	because	it is
	   only	used in	delta CRLs which are not currently implemented.

       -crl_hold instruction
	   This	sets the CRL revocation	reason code to certificateHold and the
	   hold	instruction to instruction which must be an OID. Although any
	   OID can be used only	holdInstructionNone (the use of	which is
	   discouraged by RFC2459) holdInstructionCallIssuer or
	   holdInstructionReject will normally be used.

       -crl_compromise time
	   This	sets the revocation reason to keyCompromise and	the compromise
	   time	to time. time should be	in GeneralizedTime format that is

       -crl_CA_compromise time
	   This	is the same as crl_compromise except the revocation reason is
	   set to CACompromise.

       -crlexts	section
	   The section of the configuration file containing CRL	extensions to
	   include. If no CRL extension	section	is present then	a V1 CRL is
	   created, if the CRL extension section is present (even if it	is
	   empty) then a V2 CRL	is created. The	CRL extensions specified are
	   CRL extensions and not CRL entry extensions.	 It should be noted
	   that	some software (for example Netscape) can't handle V2 CRLs. See
	   x509v3_config(5) manual page	for details of the extension section

       The section of the configuration	file containing	options	for ca is
       found as	follows: If the	-name command line option is used, then	it
       names the section to be used. Otherwise the section to be used must be
       named in	the default_ca option of the ca	section	of the configuration
       file (or	in the default section of the configuration file). Besides
       default_ca, the following options are read directly from	the ca
	msie_hack With the exception of	RANDFILE, this is probably a bug and
       may change in future releases.

       Many of the configuration file options are identical to command line
       options.	Where the option is present in the configuration file and the
       command line the	command	line value is used. Where an option is
       described as mandatory then it must be present in the configuration
       file or the command line	equivalent (if any) used.

	   This	specifies a file containing additional OBJECT IDENTIFIERS.
	   Each	line of	the file should	consist	of the numerical form of the
	   object identifier followed by white space then the short name
	   followed by white space and finally the long	name.

	   This	specifies a section in the configuration file containing extra
	   object identifiers. Each line should	consist	of the short name of
	   the object identifier followed by = and the numerical form. The
	   short and long names	are the	same when this option is used.

	   The same as the -outdir command line	option.	It specifies the
	   directory where new certificates will be placed. Mandatory.

	   The same as -cert. It gives the file	containing the CA certificate.

	   Same	as the -keyfile	option.	The file containing the	CA private
	   key.	Mandatory.

	   At startup the specified file is loaded into	the random number
	   generator, and at exit 256 bytes will be written to it.

	   The same as the -days option. The number of days to certify a
	   certificate for.

	   The same as the -startdate option. The start	date to	certify	a
	   certificate for. If not set the current time	is used.

	   The same as the -enddate option. Either this	option or default_days
	   (or the command line	equivalents) must be present.

       default_crl_hours default_crl_days
	   The same as the -crlhours and the -crldays options. These will only
	   be used if neither command line option is present. At least one of
	   these must be present to generate a CRL.

	   The same as the -md option. Mandatory except	where the signing
	   algorithm does not require a	digest (i.e. Ed25519 and Ed448).

	   The text database file to use. Mandatory. This file must be present
	   though initially it will be empty.

	   If the value	yes is given, the valid	certificate entries in the
	   database must have unique subjects.	if the value no	is given,
	   several valid certificate entries may have the exact	same subject.
	   The default value is	yes, to	be compatible with older (pre 0.9.8)
	   versions of OpenSSL.	 However, to make CA certificate roll-over
	   easier, it's	recommended to use the value no, especially if
	   combined with the -selfsign command line option.

	   Note	that it	is valid in some circumstances for certificates	to be
	   created without any subject.	In the case where there	are multiple
	   certificates	without	subjects this does not count as	a duplicate.

	   A text file containing the next serial number to use	in hex.
	   Mandatory.  This file must be present and contain a valid serial

	   A text file containing the next CRL number to use in	hex. The crl
	   number will be inserted in the CRLs only if this file exists. If
	   this	file is	present, it must contain a valid CRL number.

	   The same as -extensions.

	   The same as -crlexts.

	   The same as -preserveDN

	   The same as -noemailDN. If you want the EMAIL field to be removed
	   from	the DN of the certificate simply set this to 'no'. If not
	   present the default is to allow for the EMAIL filed in the
	   certificate's DN.

	   The same as -msie_hack

	   The same as -policy.	Mandatory. See the POLICY FORMAT section for
	   more	information.

       name_opt, cert_opt
	   These options allow the format used to display the certificate
	   details when	asking the user	to confirm signing. All	the options
	   supported by	the x509 utilities -nameopt and	-certopt switches can
	   be used here, except	the no_signame and no_sigdump are permanently
	   set and cannot be disabled (this is because the certificate
	   signature cannot be displayed because the certificate has not been
	   signed at this point).

	   For convenience the values ca_default are accepted by both to
	   produce a reasonable	output.

	   If neither option is	present	the format used	in earlier versions of
	   OpenSSL is used. Use	of the old format is strongly discouraged
	   because it only displays fields mentioned in	the policy section,
	   mishandles multicharacter string types and does not display

	   Determines how extensions in	certificate requests should be
	   handled.  If	set to none or this option is not present then
	   extensions are ignored and not copied to the	certificate. If	set to
	   copy	then any extensions present in the request that	are not
	   already present are copied to the certificate. If set to copyall
	   then	all extensions in the request are copied to the	certificate:
	   if the extension is already present in the certificate it is
	   deleted first. See the WARNINGS section before using	this option.

	   The main use	of this	option is to allow a certificate request to
	   supply values for certain extensions	such as	subjectAltName.

       The policy section consists of a	set of variables corresponding to
       certificate DN fields. If the value is "match" then the field value
       must match the same field in the	CA certificate.	If the value is
       "supplied" then it must be present. If the value	is "optional" then it
       may be present. Any fields not mentioned	in the policy section are
       silently	deleted, unless	the -preserveDN	option is set but this can be
       regarded	more of	a quirk	than intended behaviour.

       The input to the	-spkac command line option is a	Netscape signed	public
       key and challenge. This will usually come from the KEYGEN tag in	an
       HTML form to create a new private key.  It is however possible to
       create SPKACs using the spkac utility.

       The file	should contain the variable SPKAC set to the value of the
       SPKAC and also the required DN components as name value pairs.  If you
       need to include the same	component twice	then it	can be preceded	by a
       number and a '.'.

       When processing SPKAC format, the output	is DER if the -out flag	is
       used, but PEM format if sending to stdout or the	-outdir	flag is	used.

       Note: these examples assume that	the ca directory structure is already
       set up and the relevant files already exist. This usually involves
       creating	a CA certificate and private key with req, a serial number
       file and	an empty index file and	placing	them in	the relevant

       To use the sample configuration file below the directories demoCA,
       demoCA/private and demoCA/newcerts would	be created. The	CA certificate
       would be	copied to demoCA/cacert.pem and	its private key	to
       demoCA/private/cakey.pem. A file	demoCA/serial would be created
       containing for example "01" and the empty index file demoCA/index.txt.

       Sign a certificate request:

	openssl	ca -in req.pem -out newcert.pem

       Sign a certificate request, using CA extensions:

	openssl	ca -in req.pem -extensions v3_ca -out newcert.pem

       Generate	a CRL

	openssl	ca -gencrl -out	crl.pem

       Sign several requests:

	openssl	ca -infiles req1.pem req2.pem req3.pem

       Certify a Netscape SPKAC:

	openssl	ca -spkac spkac.txt

       A sample	SPKAC file (the	SPKAC line has been truncated for clarity):

	CN=Steve Test
	0.OU=OpenSSL Group
	1.OU=Another Group

       A sample	configuration file with	the relevant sections for ca:

	[ ca ]
	default_ca	= CA_default		# The default ca section

	[ CA_default ]

	dir	       = ./demoCA	       # top dir
	database       = $dir/index.txt	       # index file.
	new_certs_dir  = $dir/newcerts	       # new certs dir

	certificate    = $dir/cacert.pem       # The CA	cert
	serial	       = $dir/serial	       # serial	no file
	#rand_serial	= yes		       # for random serial#'s
	private_key    = $dir/private/cakey.pem# CA private key
	RANDFILE       = $dir/private/.rand    # random	number file

	default_days   = 365		       # how long to certify for
	default_crl_days= 30		       # how long before next CRL
	default_md     = md5		       # md to use

	policy	       = policy_any	       # default policy
	email_in_dn    = no		       # Don't add the email into cert DN

	name_opt       = ca_default	       # Subject name display option
	cert_opt       = ca_default	       # Certificate display option
	copy_extensions	= none		       # Don't copy extensions from request

	[ policy_any ]
	countryName	       = supplied
	stateOrProvinceName    = optional
	organizationName       = optional
	organizationalUnitName = optional
	commonName	       = supplied
	emailAddress	       = optional

       Note: the location of all files can change either by compile time
       options,	configuration file entries, environment	variables or command
       line options.  The values below reflect the default values.

	/usr/local/ssl/lib/openssl.cnf - master	configuration file
	./demoCA		       - main CA directory
	./demoCA/cacert.pem	       - CA certificate
	./demoCA/private/cakey.pem     - CA private key
	./demoCA/serial		       - CA serial number file
	./demoCA/serial.old	       - CA serial number backup file
	./demoCA/index.txt	       - CA text database file
	./demoCA/index.txt.old	       - CA text database backup file
	./demoCA/certs		       - certificate output file
	./demoCA/.rnd		       - CA random seed	information

       The text	database index file is a critical part of the process and if
       corrupted it can	be difficult to	fix. It	is theoretically possible to
       rebuild the index file from all the issued certificates and a current
       CRL: however there is no	option to do this.

       V2 CRL features like delta CRLs are not currently supported.

       Although	several	requests can be	input and handled at once it is	only
       possible	to include one SPKAC or	self-signed certificate.

       The use of an in-memory text database can cause problems	when large
       numbers of certificates are present because, as the name	implies	the
       database	has to be kept in memory.

       The ca command really needs rewriting or	the required functionality
       exposed at either a command or interface	level so a more	friendly
       utility (perl script or GUI) can	handle things properly.	The script helps a little but	not very much.

       Any fields in a request that are	not present in a policy	are silently
       deleted.	This does not happen if	the -preserveDN	option is used.	To
       enforce the absence of the EMAIL	field within the DN, as	suggested by
       RFCs, regardless	the contents of	the request' subject the -noemailDN
       option can be used. The behaviour should	be more	friendly and

       Canceling some commands by refusing to certify a	certificate can	create
       an empty	file.

       The ca command is quirky	and at times downright unfriendly.

       The ca utility was originally meant as an example of how	to do things
       in a CA.	It was not supposed to be used as a full blown CA itself:
       nevertheless some people	are using it for this purpose.

       The ca command is effectively a single user command: no locking is done
       on the various files and	attempts to run	more than one ca command on
       the same	database can have unpredictable	results.

       The copy_extensions option should be used with caution. If care is not
       taken then it can be a security risk. For example if a certificate
       request contains	a basicConstraints extension with CA:TRUE and the
       copy_extensions value is	set to copyall and the user does not spot this
       when the	certificate is displayed then this will	hand the requester a
       valid CA	certificate.

       This situation can be avoided by	setting	copy_extensions	to copy	and
       including basicConstraints with CA:FALSE	in the configuration file.
       Then if the request contains a basicConstraints extension it will be

       It is advisable to also include values for other	extensions such	as
       keyUsage	to prevent a request supplying its own values.

       Additional restrictions can be placed on	the CA certificate itself.
       For example if the CA certificate has:

	basicConstraints = CA:TRUE, pathlen:0

       then even if a certificate is issued with CA:TRUE it will not be	valid.

       Since OpenSSL 1.1.1, the	program	follows	RFC5280. Specifically,
       certificate validity period (specified by any of	-startdate, -enddate
       and -days) will be encoded as UTCTime if	the dates are earlier than
       year 2049 (included), and as GeneralizedTime if the dates are in	year
       2050 or later.

       req(1), spkac(1), x509(1),, config(5), x509v3_config(5)

       Copyright 2000-2021 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

1.1.1o				  2022-05-03				 CA(1)


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