NAME
SYNOPSIS
DESCRIPTION
OPTIONS
CRL OPTIONS
CONFIGURATION FILE OPTIONS
POLICY FORMAT
SPKAC FORMAT
EXAMPLES
FILES
RESTRICTIONS
BUGS
WARNINGS
HISTORY
SEE ALSO
COPYRIGHT

NAME

openssl-ca - sample minimal CA application

SYNOPSIS

openssl ca [-help] [-verbose] [-config filename] [-name section] [-section 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] [-crlsec seconds] [-crlexts section] [-startdate date] [-enddate date] [-days arg] [-md arg] [-policy arg] [-keyfile arg] [-keyform DER|PEM] [-key arg] [-passin arg] [-cert file] [-certform DER|<PEM>] [-selfsign] [-in file] [-inform DER|<PEM>] [-out file] [-notext] [-outdir dir] [-infiles] [-spkac file] [-ss_cert file] [-preserveDN] [-noemailDN] [-batch] [-msie_hack] [-extensions section] [-extfile section] [-subj arg] [-utf8] [-sigopt nm:v] [-vfyopt nm:v] [-create_serial] [-rand_serial] [-multivalue-rdn] [-rand files] [-writerand file] [-engine id] [-provider name] [-provider_path path] [certreq...]

DESCRIPTION

This 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. When signing certificates, a single certificate request can be specified with the -in option, or multiple requests can be processed by specifying a set of certreq files after all options.

The options descriptions will be divided into each purpose.

OPTIONS

-help

Print out a usage message.

-verbose

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 -name section, -section 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.

-inform DER|PEM

The format of the data in CSR input files. The default is PEM.

-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 format.

-infiles

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.

-cert

The CA certificate file.

-certform DER|PEM

The format of the data in certificate input files. The default is PEM.

-keyfile filename

The private key to sign requests with.

-keyform DER|PEM

The format of the private key file; the default is PEM. See -sigopt nm:v

Pass options to the signature algorithm during sign operations. Names and values of these options are algorithm-specific.

-vfyopt nm:v

Pass options to the signature algorithm during verify operations. Names and values of these options are algorithm-specific.

This often needs to be given while signing too, because the input certificate signature request is verified against its own public key, and that verification may need its own set of options.

-key password

The password used to encrypt the private key. Since on some systems the command line arguments are visible (e.g., when using -selfsign

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 certificate.

-passin arg

The key password source. For more information about the format of arg see -notext

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 -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.

-msie_hack

This is a deprecated option to make this command 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.

-preserveDN

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.

-noemailDN

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 behaviour.

-batch

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 -extfile file

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

-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.

-utf8

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.

-create_serial

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.

-rand_serial

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

-multivalue-rdn

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 files, -writerand file

See -engine id

See -provider name

-provider_path path

See CRL OPTIONS

-gencrl

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.

-crlsec num

The number of seconds 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 entry.

-status serial

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

-updatedb

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 YYYYMMDDHHMMSSZ.

-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 CONFIGURATION FILE OPTIONS

The section of the configuration file containing options for this command 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 section: RANDFILE preserve 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.

oid_file: 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.
oid_section: 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.
new_certs_dir: The same as the -outdir command line option. It specifies the directory where new certificates will be placed. Mandatory.
certificate: The same as -cert. It gives the file containing the CA certificate. Mandatory.
private_key: Same as the -keyfile option. The file containing the CA private key. Mandatory.
RANDFILE

POLICY FORMAT

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.

SPKAC FORMAT

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 EXAMPLES

Note: these examples assume that the directory structure this command assumes is already set up and the relevant files already exist. This usually involves creating a CA certificate and private key with FILES

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

RESTRICTIONS

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.

BUGS

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.

This command really needs rewriting or the required functionality exposed at either a command or interface level so that a more user-friendly replacement could handle things properly. The script CA.pl 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 configurable.

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

WARNINGS

This command is quirky and at times downright unfriendly.

This command 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.

This command command is effectively a single user command: no locking is done on the various files and attempts to run more than one openssl 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 ignored.

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.

HISTORY

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.

OpenSSL 1.1.1 introduced a new random generator (CSPRNG) with an improved seeding mechanism. The new seeding mechanism makes it unnecessary to define a RANDFILE for saving and restoring randomness. This option is retained mainly for compatibility reasons.

The -section option was added in OpenSSL 3.0.0.

OpenSSL.vip

Cryptography and SSL/TLS Toolkit