certtool(1) — Linux manual page

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certtool(1)                   User Commands                  certtool(1)

NAME         top

       certtool - GnuTLS certificate tool

SYNOPSIS         top

       certtool [-flags] [-flag [value]] [--option-name[[=| ]value]]

       All arguments must be options.

DESCRIPTION         top

       Tool to parse and generate X.509 certificates, requests and
       private keys.  It can be used interactively or non interactively
       by specifying the template command line option.

       The tool accepts files or supported URIs via the --infile option.
       In case PIN is required for URI access you can provide it using
       the environment variables GNUTLS_PIN and GNUTLS_SO_PIN.

OPTIONS         top

       -d num, --debug=num Enable debugging.  This option takes an
       integer number as its argument.  The value of num is constrained
       to being:
           in the range 0 through 9999

       Specifies the debug level.

       -V, --verbose More verbose output.

       --infile=file Input file.

       --outfile=str Output file.

       --attime=timestamp Perform validation at the timestamp instead of
       the system time.

       timestamp is an instance in time encoded as Unix time or in a
       human
        readable timestring such as "29 Feb 2004", "2004-02-29".  Full
       documentation available at
       <https://www.gnu.org/software/coreutils/manual/html_node/Date-input-formats.html>
       or locally via info '(coreutils) date invocation'.

          Certificate related options

       -i, --certificate-info Print information on the given
       certificate.

       --pubkey-info Print information on a public key.

       The option combined with --load-request, --load-pubkey,
       --load-privkey and --load-certificate will extract the public key
       of the object in question.

       -s, --generate-self-signed Generate a self-signed certificate.

       -c, --generate-certificate Generate a signed certificate.

       --generate-proxy Generates a proxy certificate.

       -u, --update-certificate Update a signed certificate.

       --fingerprint Print the fingerprint of the given certificate.

       This is a simple hash of the DER encoding of the certificate. It
       can be combined with the --hash parameter. However, it is
       recommended for identification to use the key-id which depends
       only on the certificate's key.

       --key-id Print the key ID of the given certificate.

       This is a hash of the public key of the given certificate. It
       identifies the key uniquely, remains the same on a certificate
       renewal and depends only on signed fields of the certificate.

       --certificate-pubkey Print certificate's public key.

       This option is deprecated as a duplicate of --pubkey-info

       NOTE: THIS OPTION IS DEPRECATED

       --v1 Generate an X.509 version 1 certificate (with no
       extensions).

       --sign-params=str Sign a certificate with a specific signature
       algorithm.

       This option can be combined with --generate-certificate, to sign
       the certificate with a specific signature algorithm variant. The
       only option supported is 'RSA-PSS', and should be specified when
       the signer does not have a certificate which is marked for
       RSA-PSS use only.

          Certificate request related options

       --crq-info Print information on the given certificate request.

       -q, --generate-request Generate a PKCS #10 certificate request.
       This option must not appear in combination with any of the
       following options: infile.

       Will generate a PKCS #10 certificate request. To specify a
       private key use --load-privkey.

       --no-crq-extensions Do not use extensions in certificate
       requests.

          PKCS#12 file related options

       --p12-info Print information on a PKCS #12 structure.

       This option will dump the contents and print the metadata of the
       provided PKCS #12 structure.

       --p12-name=str The PKCS #12 friendly name to use.

       The name to be used for the primary certificate and private key
       in a PKCS #12 file.

       --to-p12 Generate a PKCS #12 structure.

       It requires a certificate, a private key and possibly a CA
       certificate to be specified.

          Private key related options

       -k, --key-info Print information on a private key.

       --p8-info Print information on a PKCS #8 structure.

       This option will print information about encrypted PKCS #8
       structures. That option does not require the decryption of the
       structure.

       --to-rsa Convert an RSA-PSS key to raw RSA format.

       It requires an RSA-PSS key as input and will output a raw RSA
       key. This command is necessary for compatibility with
       applications that cannot read RSA-PSS keys.

       -p, --generate-privkey Generate a private key.

       When generating RSA-PSS or RSA-OAEP private keys, the --hash
       option will restrict the allowed hash for the key; For RSA-PSS
       keys the --salt-size option is also acceptable.

       --key-type=str Specify the key type to use on key generation.

       This option can be combined with --generate-privkey, to specify
       the key type to be generated. Valid options are, 'rsa',
       'rsa-pss', 'rsa-oaep', 'dsa', 'ecdsa', 'ed25519, 'ed448',
       'x25519', and 'x448'.'.  When combined with certificate
       generation it can be used to specify an RSA-PSS certificate when
       an RSA key is given.

       --bits=num Specify the number of bits for key generation.  This
       option takes an integer number as its argument.

       --curve=str Specify the curve used for EC key generation.

       Supported values are secp192r1, secp224r1, secp256r1, secp384r1
       and secp521r1.

       --sec-param=security parameter Specify the security level [low,
       legacy, medium, high, ultra].

       This is alternative to the bits option.

       --to-p8 Convert a given key to a PKCS #8 structure.

       This needs to be combined with --load-privkey.

       -8, --pkcs8 Use PKCS #8 format for private keys.

       --provable Generate a private key or parameters from a seed using
       a provable method.

       This will use the FIPS PUB186-4 algorithms (i.e., Shawe-Taylor)
       for provable key generation.  When specified the private keys or
       parameters will be generated from a seed, and can be later
       validated with --verify-provable-privkey to be correctly
       generated from the seed. You may specify --seed or allow GnuTLS
       to generate one (recommended). This option can be combined with
       --generate-privkey or --generate-dh-params.

       That option applies to RSA and DSA keys. On the DSA keys the PQG
       parameters are generated using the seed, and on RSA the two
       primes.

       --verify-provable-privkey Verify a private key generated from a
       seed using a provable method.

       This will use the FIPS-186-4 algorithms for provable key
       generation. You may specify --seed or use the seed stored in the
       private key structure.

       --seed=str When generating a private key use the given hex-
       encoded seed.

       The seed acts as a security parameter for the private key, and
       thus a seed size which corresponds to the security level of the
       private key should be provided (e.g., 256-bits seed).

          CRL related options

       -l, --crl-info Print information on the given CRL structure.

       --generate-crl Generate a CRL.

       This option generates a Certificate Revocation List. When
       combined with --load-crl it would use the loaded CRL as base for
       the generated (i.e., all revoked certificates in the base will be
       copied to the new CRL).  To add new certificates to the CRL use
       --load-certificate.

       --verify-crl Verify a Certificate Revocation List using a trusted
       list.  This option must appear in combination with the following
       options: load-ca-certificate.

       The trusted certificate list must be loaded with
       --load-ca-certificate.

          Certificate verification related options

       -e, --verify-chain Verify a PEM encoded certificate chain.

       Verifies the validity of a certificate chain. That is, an ordered
       set of certificates where each one is the issuer of the previous,
       and the first is the end-certificate to be validated. In a proper
       chain the last certificate is a self signed one. It can be
       combined with --verify-purpose or --verify-hostname.

       --verify Verify a PEM encoded certificate (chain) against a
       trusted set.

       The trusted certificate list can be loaded with
       --load-ca-certificate. If no certificate list is provided, then
       the system's trusted certificate list is used. Note that during
       verification multiple paths may be explored. On a successful
       verification the successful path will be the last one. It can be
       combined with --verify-purpose or --verify-hostname.

       --verify-hostname=str Specify a hostname to be used for
       certificate chain verification.

       This is to be combined with one of the verify certificate
       options.

       --verify-email=str Specify a email to be used for certificate
       chain verification.  This option must not appear in combination
       with any of the following options: verify-hostname.

       This is to be combined with one of the verify certificate
       options.

       --verify-purpose=str Specify a purpose OID to be used for
       certificate chain verification.

       This object identifier restricts the purpose of the certificates
       to be verified. Example purposes are 1.3.6.1.5.5.7.3.1 (TLS WWW),
       1.3.6.1.5.5.7.3.4 (EMAIL) etc. Note that a CA certificate without
       a purpose set (extended key usage) is valid for any purpose.

       --verify-allow-broken Allow broken algorithms, such as MD5 for
       verification.

       This can be combined with --p7-verify, --verify or
       --verify-chain.

       --verify-profile=str Specify a security level profile to be used
       for verification.

       This option can be used to specify a certificate verification
       profile. Certificate
           verification profiles correspond to the security level. This
       should be one of
           'none', 'very weak', 'low', 'legacy', 'medium', 'high',
       'ultra',
           'future'. Note that by default no profile is applied, unless
       one is set
           as minimum in the gnutls configuration file.

          PKCS#7 structure options

       --p7-generate Generate a PKCS #7 structure.

       This option generates a PKCS #7 certificate container structure.
       To add certificates in the structure use --load-certificate and
       --load-crl.

       --p7-sign Signs using a PKCS #7 structure.

       This option generates a PKCS #7 structure containing a signature
       for the provided data from infile. The data are stored within the
       structure. The signer certificate has to be specified using
       --load-certificate and --load-privkey. The input to
       --load-certificate can be a list of certificates. In case of a
       list, the first certificate is used for signing and the other
       certificates are included in the structure.

       --p7-detached-sign Signs using a detached PKCS #7 structure.

       This option generates a PKCS #7 structure containing a signature
       for the provided data from infile. The signer certificate has to
       be specified using --load-certificate and --load-privkey. The
       input to --load-certificate can be a list of certificates. In
       case of a list, the first certificate is used for signing and the
       other certificates are included in the structure.

       --p7-include-cert, --no-p7-include-cert The signer's certificate
       will be included in the cert list.  The no-p7-include-cert form
       will disable the option.  This option is enabled by default.

       This options works with --p7-sign or --p7-detached-sign and will
       include or exclude the signer's certificate into the generated
       signature.

       --p7-time, --no-p7-time Will include a timestamp in the PKCS #7
       structure.  The no-p7-time form will disable the option.

       This option will include a timestamp in the generated signature

       --p7-show-data, --no-p7-show-data Will show the embedded data in
       the PKCS #7 structure.  The no-p7-show-data form will disable the
       option.

       This option can be combined with --p7-verify or --p7-info and
       will display the embedded signed data in the PKCS #7 structure.

       --p7-info Print information on a PKCS #7 structure.

       --p7-verify Verify the provided PKCS #7 structure.

       This option verifies the signed PKCS #7 structure. The
       certificate list to use for verification can be specified with
       --load-ca-certificate. When no certificate list is provided, then
       the system's certificate list is used. Alternatively a direct
       signer can be provided using --load-certificate. A key purpose
       can be enforced with the --verify-purpose option, and the
       --load-data option will utilize detached data.

       --smime-to-p7 Convert S/MIME to PKCS #7 structure.

          Other options

       --generate-dh-params Generate PKCS #3 encoded Diffie-Hellman
       parameters.

       The will generate random parameters to be used with
       Diffie-Hellman key exchange. The output parameters will be in
       PKCS #3 format. Note that it is recommended to use the
       --get-dh-params option instead.

       NOTE: THIS OPTION IS DEPRECATED

       --get-dh-params List the included PKCS #3 encoded Diffie-Hellman
       parameters.

       Returns stored DH parameters in GnuTLS. Those parameters returned
       are defined in RFC7919, and can be considered standard parameters
       for a TLS key exchange. This option is provided for old
       applications which require DH parameters to be specified; modern
       GnuTLS applications should not require them.

       --dh-info Print information PKCS #3 encoded Diffie-Hellman
       parameters.

       --load-privkey=str Loads a private key file.

       This can be either a file or a PKCS #11 URL

       --load-pubkey=str Loads a public key file.

       This can be either a file or a PKCS #11 URL

       --load-request=str Loads a certificate request file.

       This option can be used with a file

       --load-certificate=str Loads a certificate file.

       This option can be used with a file

       --load-ca-privkey=str Loads the certificate authority's private
       key file.

       This can be either a file or a PKCS #11 URL

       --load-ca-certificate=str Loads the certificate authority's
       certificate file.

       This can be either a file or a PKCS #11 URL

       --load-crl=str Loads the provided CRL.

       This option can be used with a file

       --load-data=str Loads auxiliary data.

       This option can be used with a file

       --password=str Password to use.

       You can use this option to specify the password in the command
       line instead of reading it from the tty. Note, that the command
       line arguments are available for view in others in the system.
       Specifying password as '' is the same as specifying no password.

       --null-password Enforce a NULL password.

       This option enforces a NULL password. This is different than the
       empty or no password in schemas like PKCS #8.

       --empty-password Enforce an empty password.

       This option enforces an empty password. This is different than
       the NULL or no password in schemas like PKCS #8.

       --hex-numbers Print big number in an easier format to parse.

       --cprint In certain operations it prints the information in C-
       friendly format.

       In certain operations it prints the information in C-friendly
       format, suitable for including into C programs.

       --rsa Generate RSA key.

       When combined with --generate-privkey generates an RSA private
       key.

       NOTE: THIS OPTION IS DEPRECATED

       --dsa Generate DSA key.

       When combined with --generate-privkey generates a DSA private
       key.

       NOTE: THIS OPTION IS DEPRECATED

       --ecc Generate ECC (ECDSA) key.

       When combined with --generate-privkey generates an elliptic curve
       private key to be used with ECDSA.

       NOTE: THIS OPTION IS DEPRECATED

       --ecdsa This is an alias for the --ecc option.

       NOTE: THIS OPTION IS DEPRECATED

       --hash=str Hash algorithm to use for signing.

       Available hash functions are SHA1, RMD160, SHA256, SHA384,
       SHA512, SHA3-224, SHA3-256, SHA3-384, SHA3-512.

       --salt-size=num Specify the RSA-PSS key default salt size.  This
       option takes an integer number as its argument.

       Typical keys shouldn't set or restrict this option.

       --label=str Specify the RSA-OAEP label, encoded in hexadecimal.

       Typical keys shouldn't set or restrict this option.

       --inder, --no-inder Use DER format for input certificates,
       private keys, and DH parameters .  The no-inder form will disable
       the option.

       The input files will be assumed to be in DER or RAW format.
       Unlike options that in PEM input would allow multiple input data
       (e.g. multiple certificates), when reading in DER format a single
       data structure is read.

       --inraw This is an alias for the --inder option.

       --outder, --no-outder Use DER format for output certificates,
       private keys, and DH parameters.  The no-outder form will disable
       the option.

       The output will be in DER or RAW format.

       --outraw This is an alias for the --outder option.

       --disable-quick-random No effect.

       NOTE: THIS OPTION IS DEPRECATED

       --template=str Template file to use for non-interactive
       operation.

       --stdout-info Print information to stdout instead of stderr.

       --ask-pass Enable interaction for entering password when in batch
       mode.

       This option will enable interaction to enter password when in
       batch mode. That is useful when the template option has been
       specified.

       --pkcs-cipher=cipher Cipher to use for PKCS #8 and #12
       operations.

       Cipher may be one of 3des, 3des-pkcs12, aes-128, aes-192,
       aes-256, rc2-40, arcfour.

       --provider=str Specify the PKCS #11 provider library.

       This will override the default options in /etc/gnutls/pkcs11.conf

       --text, --no-text Output textual information before PEM-encoded
       certificates, private keys, etc.  The no-text form will disable
       the option.  This option is enabled by default.

       Output textual information before PEM-encoded data

       -v arg, --version=arg Output version of program and exit.  The
       default mode is `v', a simple version.  The `c' mode will print
       copyright information and `n' will print the full copyright
       notice.

       -h, --help Display usage information and exit.

       -!, --more-help Pass the extended usage information through a
       pager.

FILES         top

              Certtool's template file format
              A template file can be used to avoid the interactive
              questions of certtool. Initially create a file named
              'cert.cfg' that contains the information about the
              certificate. The template can be used as below:

                  $ certtool --generate-certificate --load-privkey key.pem     --template cert.cfg --outfile cert.pem    --load-ca-certificate ca-cert.pem --load-ca-privkey ca-key.pem

              An example certtool template file that can be used to
              generate a certificate request or a self signed
              certificate follows.

                  # X.509 Certificate options
                  #
                  # DN options

                  # The organization of the subject.
                  organization = "Koko inc."

                  # The organizational unit of the subject.
                  unit = "sleeping dept."

                  # The locality of the subject.
                  # locality =

                  # The state of the certificate owner.
                  state = "Attiki"

                  # The country of the subject. Two letter code.
                  country = GR

                  # The common name of the certificate owner.
                  cn = "Cindy Lauper"

                  # A user id of the certificate owner.
                  #uid = "clauper"

                  # Set domain components
                  #dc = "name"
                  #dc = "domain"

                  # If the supported DN OIDs are not adequate you can set
                  # any OID here.
                  # For example set the X.520 Title and the X.520 Pseudonym
                  # by using OID and string pairs.
                  #dn_oid = "2.5.4.12 Dr."
                  #dn_oid = "2.5.4.65 jackal"

                  # This is deprecated and should not be used in new
                  # certificates.
                  # pkcs9_email = "none@none.org"

                  # An alternative way to set the certificate's distinguished name directly
                  # is with the "dn" option. The attribute names allowed are:
                  # C (country), street, O (organization), OU (unit), title, CN (common name),
                  # L (locality), ST (state), placeOfBirth, gender, countryOfCitizenship,
                  # countryOfResidence, serialNumber, telephoneNumber, surName, initials,
                  # generationQualifier, givenName, pseudonym, dnQualifier, postalCode, name,
                  # businessCategory, DC, UID, jurisdictionOfIncorporationLocalityName,
                  # jurisdictionOfIncorporationStateOrProvinceName,
                  # jurisdictionOfIncorporationCountryName, XmppAddr, and numeric OIDs.

                  #dn = "cn = Nikos,st = New Something,C=GR,surName=Mavrogiannopoulos,2.5.4.9=Arkadias"

                  # The serial number of the certificate
                  # The value is in decimal (i.e. 1963) or hex (i.e. 0x07ab).
                  # Comment the field for a random serial number.
                  serial = 007

                  # In how many days, counting from today, this certificate will expire.
                  # Use -1 if there is no expiration date.
                  expiration_days = 700

                  # Alternatively you may set concrete dates and time. The GNU date string
                  # formats are accepted. See:
                  # https://www.gnu.org/software/tar/manual/html_node/Date-input-formats.html

                  #activation_date = "2004-02-29 16:21:42"
                  #expiration_date = "2025-02-29 16:24:41"

                  # X.509 v3 extensions

                  # A dnsname in case of a WWW server.
                  #dns_name = "www.none.org"
                  #dns_name = "www.morethanone.org"

                  # An othername defined by an OID and a hex encoded string
                  #other_name = "1.3.6.1.5.2.2 302ca00d1b0b56414e5245494e2e4f5247a11b3019a006020400000002a10f300d1b047269636b1b0561646d696e"
                  #other_name_utf8 = "1.2.4.5.6 A UTF8 string"
                  #other_name_octet = "1.2.4.5.6 A string that will be encoded as ASN.1 octet string"

                  # Allows writing an XmppAddr Identifier
                  #xmpp_name = juliet@im.example.com

                  # Names used in PKINIT
                  #krb5_principal = user@REALM.COM
                  #krb5_principal = HTTP/user@REALM.COM

                  # A subject alternative name URI
                  #uri = "https://www.example.com"

                  # An IP address in case of a server.
                  #ip_address = "192.168.1.1"

                  # An email in case of a person
                  email = "none@none.org"

                  # TLS feature (rfc7633) extension. That can is used to indicate mandatory TLS
                  # extension features to be provided by the server. In practice this is used
                  # to require the Status Request (extid: 5) extension from the server. That is,
                  # to require the server holding this certificate to provide a stapled OCSP response.
                  # You can have multiple lines for multiple TLS features.

                  # To ask for OCSP status request use:
                  #tls_feature = 5

                  # Challenge password used in certificate requests
                  challenge_password = 123456

                  # Password when encrypting a private key
                  #password = secret

                  # An URL that has CRLs (certificate revocation lists)
                  # available. Needed in CA certificates.
                  #crl_dist_points = "https://www.getcrl.crl/getcrl/"

                  # Whether this is a CA certificate or not
                  #ca

                  # Subject Unique ID (in hex)
                  #subject_unique_id = 00153224

                  # Issuer Unique ID (in hex)
                  #issuer_unique_id = 00153225

                  #### Key usage

                  # The following key usage flags are used by CAs and end certificates

                  # Whether this certificate will be used to sign data (needed
                  # in TLS DHE ciphersuites). This is the digitalSignature flag
                  # in RFC5280 terminology.
                  signing_key

                  # Whether this certificate will be used to encrypt data (needed
                  # in TLS RSA ciphersuites). Note that it is preferred to use different
                  # keys for encryption and signing. This is the keyEncipherment flag
                  # in RFC5280 terminology.
                  encryption_key

                  # Whether this key will be used to sign other certificates. The
                  # keyCertSign flag in RFC5280 terminology.
                  #cert_signing_key

                  # Whether this key will be used to sign CRLs. The
                  # cRLSign flag in RFC5280 terminology.
                  #crl_signing_key

                  # The keyAgreement flag of RFC5280. Its purpose is loosely
                  # defined. Not use it unless required by a protocol.
                  #key_agreement

                  # The dataEncipherment flag of RFC5280. Its purpose is loosely
                  # defined. Not use it unless required by a protocol.
                  #data_encipherment

                  # The nonRepudiation flag of RFC5280. Its purpose is loosely
                  # defined. Not use it unless required by a protocol.
                  #non_repudiation

                  #### Extended key usage (key purposes)

                  # The following extensions are used in an end certificate
                  # to clarify its purpose. Some CAs also use it to indicate
                  # the types of certificates they are purposed to sign.

                  # Whether this certificate will be used for a TLS client;
                  # this sets the id-kp-clientAuth (1.3.6.1.5.5.7.3.2) of
                  # extended key usage.
                  #tls_www_client

                  # Whether this certificate will be used for a TLS server;
                  # this sets the id-kp-serverAuth (1.3.6.1.5.5.7.3.1) of
                  # extended key usage.
                  #tls_www_server

                  # Whether this key will be used to sign code. This sets the
                  # id-kp-codeSigning (1.3.6.1.5.5.7.3.3) of extended key usage
                  # extension.
                  #code_signing_key

                  # Whether this key will be used to sign OCSP data. This sets the
                  # id-kp-OCSPSigning (1.3.6.1.5.5.7.3.9) of extended key usage extension.
                  #ocsp_signing_key

                  # Whether this key will be used for time stamping. This sets the
                  # id-kp-timeStamping (1.3.6.1.5.5.7.3.8) of extended key usage extension.
                  #time_stamping_key

                  # Whether this key will be used for email protection. This sets the
                  # id-kp-emailProtection (1.3.6.1.5.5.7.3.4) of extended key usage extension.
                  #email_protection_key

                  # Whether this key will be used for IPsec IKE operations (1.3.6.1.5.5.7.3.17).
                  #ipsec_ike_key

                  ## adding custom key purpose OIDs

                  # for microsoft smart card logon
                  # key_purpose_oid = 1.3.6.1.4.1.311.20.2.2

                  # for email protection
                  # key_purpose_oid = 1.3.6.1.5.5.7.3.4

                  # for any purpose (must not be used in intermediate CA certificates)
                  # key_purpose_oid = 2.5.29.37.0

                  ### end of key purpose OIDs

                  ### Adding arbitrary extensions
                  # This requires to provide the extension OIDs, as well as the extension data in
                  # hex format. The following two options are available since GnuTLS 3.5.3.
                  #add_extension = "1.2.3.4 0x0AAB01ACFE"

                  # As above but encode the data as an octet string
                  #add_extension = "1.2.3.4 octet_string(0x0AAB01ACFE)"

                  # For portability critical extensions shouldn't be set to certificates.
                  #add_critical_extension = "5.6.7.8 0x1AAB01ACFE"

                  # When generating a certificate from a certificate
                  # request, then honor the extensions stored in the request
                  # and store them in the real certificate.
                  #honor_crq_extensions

                  # Alternatively only specific extensions can be copied.
                  #honor_crq_ext = 2.5.29.17
                  #honor_crq_ext = 2.5.29.15

                  # Path length constraint. Sets the maximum number of
                  # certificates that can be used to certify this certificate.
                  # (i.e. the certificate chain length)
                  #path_len = -1
                  #path_len = 2

                  # OCSP URI
                  # ocsp_uri = https://my.ocsp.server/ocsp

                  # CA issuers URI
                  # ca_issuers_uri = https://my.ca.issuer

                  # Certificate policies
                  #policy1 = 1.3.6.1.4.1.5484.1.10.99.1.0
                  #policy1_txt = "This is a long policy to summarize"
                  #policy1_url = https://www.example.com/a-policy-to-read

                  #policy2 = 1.3.6.1.4.1.5484.1.10.99.1.1
                  #policy2_txt = "This is a short policy"
                  #policy2_url = https://www.example.com/another-policy-to-read

                  # The number of additional certificates that may appear in a
                  # path before the anyPolicy is no longer acceptable.
                  #inhibit_anypolicy_skip_certs 1

                  # Name constraints

                  # DNS
                  #nc_permit_dns = example.com
                  #nc_exclude_dns = test.example.com

                  # EMAIL
                  #nc_permit_email = "nmav@ex.net"

                  # Exclude subdomains of example.com
                  #nc_exclude_email = .example.com

                  # Exclude all e-mail addresses of example.com
                  #nc_exclude_email = example.com

                  # IP
                  #nc_permit_ip = 192.168.0.0/16
                  #nc_exclude_ip = 192.168.5.0/24
                  #nc_permit_ip = fc0a:eef2:e7e7:a56e::/64

                  # Options for proxy certificates
                  #proxy_policy_language = 1.3.6.1.5.5.7.21.1

                  # Options for generating a CRL

                  # The number of days the next CRL update will be due.
                  # next CRL update will be in 43 days
                  #crl_next_update = 43

                  # this is the 5th CRL by this CA
                  # The value is in decimal (i.e. 1963) or hex (i.e. 0x07ab).
                  # Comment the field for a time-based number.
                  # Time-based CRL numbers generated in GnuTLS 3.6.3 and later
                  # are significantly larger than those generated in previous
                  # versions. Since CRL numbers need to be monotonic, you need
                  # to specify the CRL number here manually if you intend to
                  # downgrade to an earlier version than 3.6.3 after publishing
                  # the CRL as it is not possible to specify CRL numbers greater
                  # than 2**63-2 using hex notation in those versions.
                  #crl_number = 5

                  # Specify the update dates more precisely.
                  #crl_this_update_date = "2004-02-29 16:21:42"
                  #crl_next_update_date = "2025-02-29 16:24:41"

                  # The date that the certificates will be made seen as
                  # being revoked.
                  #crl_revocation_date = "2025-02-29 16:24:41"

EXAMPLES         top

       Generating private keys
       To create an RSA private key, run:
           $ certtool --generate-privkey --outfile key.pem --rsa

       To create a DSA or elliptic curves (ECDSA) private key use the
       above command combined with 'dsa' or 'ecc' options.

       Generating certificate requests
       To create a certificate request (needed when the certificate is
       issued  by another party), run:
           certtool --generate-request --load-privkey key.pem    --outfile request.pem

       If the private key is stored in a smart card you can generate a
       request by specifying the private key object URL.
           $ ./certtool --generate-request --load-privkey "pkcs11:..."   --load-pubkey "pkcs11:..." --outfile request.pem

       Generating a self-signed certificate
       To create a self signed certificate, use the command:
           $ certtool --generate-privkey --outfile ca-key.pem
           $ certtool --generate-self-signed --load-privkey ca-key.pem    --outfile ca-cert.pem

       Note that a self-signed certificate usually belongs to a
       certificate authority, that signs other certificates.

       Generating a certificate
       To generate a certificate using the previous request, use the
       command:
           $ certtool --generate-certificate --load-request request.pem    --outfile cert.pem --load-ca-certificate ca-cert.pem    --load-ca-privkey ca-key.pem

       To generate a certificate using the private key only, use the
       command:
           $ certtool --generate-certificate --load-privkey key.pem    --outfile cert.pem --load-ca-certificate ca-cert.pem    --load-ca-privkey ca-key.pem

       Certificate information
       To view the certificate information, use:
           $ certtool --certificate-info --infile cert.pem

       Changing the certificate format
       To convert the certificate from PEM to DER format, use:
           $ certtool --certificate-info --infile cert.pem --outder --outfile cert.der

       PKCS #12 structure generation
       To generate a PKCS #12 structure using the previous key and
       certificate, use the command:
           $ certtool --load-certificate cert.pem --load-privkey key.pem    --to-p12 --outder --outfile key.p12

       Some tools (reportedly web browsers) have problems with that file
       because it does not contain the CA certificate for the
       certificate.  To work around that problem in the tool, you can
       use the --load-ca-certificate parameter as follows:

           $ certtool --load-ca-certificate ca.pem   --load-certificate cert.pem --load-privkey key.pem   --to-p12 --outder --outfile key.p12

       Obtaining Diffie-Hellman parameters
       To obtain the RFC7919 parameters for Diffie-Hellman key exchange,
       use the command:
           $ certtool --get-dh-params --outfile dh.pem --sec-param medium

       Verifying a certificate
       To verify a certificate in a file against the system's CA trust
       store use the following command:
           $ certtool --verify --infile cert.pem

       It is also possible to simulate hostname verification with the
       following options:
           $ certtool --verify --verify-hostname www.example.com --infile cert.pem

       Proxy certificate generation
       Proxy certificate can be used to delegate your credential to a
       temporary, typically short-lived, certificate.  To create one
       from the previously created certificate, first create a temporary
       key and then generate a proxy certificate for it, using the
       commands:

           $ certtool --generate-privkey > proxy-key.pem
           $ certtool --generate-proxy --load-ca-privkey key.pem   --load-privkey proxy-key.pem --load-certificate cert.pem   --outfile proxy-cert.pem

       Certificate revocation list generation
       To create an empty Certificate Revocation List (CRL) do:

           $ certtool --generate-crl --load-ca-privkey x509-ca-key.pem            --load-ca-certificate x509-ca.pem

       To create a CRL that contains some revoked certificates, place
       the certificates in a file and use --load-certificate as follows:

           $ certtool --generate-crl --load-ca-privkey x509-ca-key.pem   --load-ca-certificate x509-ca.pem --load-certificate revoked-certs.pem

       To verify a Certificate Revocation List (CRL) do:

           $ certtool --verify-crl --load-ca-certificate x509-ca.pem < crl.pem

EXIT STATUS         top

       One of the following exit values will be returned:

       0  (EXIT_SUCCESS) Successful program execution.

       1  (EXIT_FAILURE) The operation failed or the command syntax was
       not valid.

SEE ALSO         top

              p11tool(1), psktool(1), srptool(1)

AUTHORS         top


COPYRIGHT         top

       Copyright (C) 2020-2023 Free Software Foundation, and others all
       rights reserved.  This program is released under the terms of the
       GNU General Public License, version 3 or later

BUGS         top

       Please send bug reports to: bugs@gnutls.org

COLOPHON         top

       This page is part of the GnuTLS (GnuTLS Transport Layer Security
       Library) project.  Information about the project can be found at
       ⟨http://www.gnutls.org/⟩.  If you have a bug report for this
       manual page, send it to bugs@gnutls.org.  This page was obtained
       from the tarball gnutls-3.8.5.tar.xz fetched from
       ⟨http://www.gnutls.org/download.html⟩ on 2024-06-14.  If you
       discover any rendering problems in this HTML version of the page,
       or you believe there is a better or more up-to-date source for
       the page, or you have corrections or improvements to the
       information in this COLOPHON (which is not part of the original
       manual page), send a mail to man-pages@man7.org

3.8.5                          04 Apr 2024                   certtool(1)

Pages that refer to this page: danetool(1)ocsptool(1)p11tool(1)psktool(1)srptool(1)tpmtool(1)