Using the Certificate Revocation List Management Tool

Newsgroup: mozilla.dev.tech.crypto
Technical contact: Alexei Volkov

The Certificate Revocation List (CRL) Management Tool is a command-line utility that can list, generate, modify, or delete CRLs within the NSS security database file(s) and list, create, modify or delete certificates entries in a particular CRL.

The key and certificate management process generally begins with creating keys in the key database, then generating and managing certificates in the certificate database(see certutil tool) and continues with certificates expiration or revocation.

This document discusses certificate revocation list management. For information on security module database management, see Using the Security Module Database Tool. For information on certificate and key database management, see Using the Certificate Database Tool.

Availability

See the release notes for the platforms this tool is available on.

Syntax

To run the Certificate Revocation List Management Tool, type the command

crlutil option [arguments]

where options and arguments are combinations of the options and arguments listed in the following section. Each command takes one option. Each option may take zero or more arguments. To see a usage string, issue the command without options, or with the -H option.

Options and Arguments

Options specify an action and are uppercase. Option arguments modify an action and are lowercase. Certificate Revocation List Management Tool command options and their arguments are defined as follows:

Options
`-G`	Create new Certificate Revocation List(CRL).
`-D`	Delete Certificate Revocation List from cert database.
`-I`	Import a CRL to the cert database
`-E`	Erase all CRLs of specified type from the cert database
`-L`	List existing CRL located in cert database file.
`-M`	Modify existing CRL which can be located in cert db or in arbitrary file. If located in file it should be encoded in ASN.1 encode format.
Arguments
`-B`	Bypass CA signature checks.
`-P` dbprefix	Specify the prefix used on the `NSS security database` files (for example, `my_cert8.db` and `my_key3.db`). This option is provided as a special case. Changing the names of the certificate and key databases is not recommended.
`-a`	Use ASCII format or allow the use of ASCII format for input and output. This formatting follows RFC #1113.
`-c` crl-gen-file	Specify script file that will be used to control crl generation/modification. See crl-cript-file format below. If options -M\|-G is used and -c crl-script-file is not specified, crlutil will read script data from standard input.
`-d` directory	Specify the database directory containing the certificate and key database files. On Unix the Certificate Database Tool defaults to `$HOME/.netscape` (that is, `~/.netscape`). On Windows NT the default is the current directory. The `NSS database` files must reside in the same directory.
`-i` crl-import-file	Specify the file which contains the CRL to import
`-f` password-file	Specify a file that will automatically supply the password to include in a certificate or to access a certificate database. This is a plain-text file containing one password. Be sure to prevent unauthorized access to this file.
`-l` algorithm-name	Specify a specific signature algorithm. List of possible algorithms: MD2 \| MD4 \| MD5 \| SHA1 \| SHA256 \| SHA384 \| SHA512
`-n` nickname	Specify the nickname of a certificate or key to list, create, add to a database, modify, or validate. Bracket the nickname string with quotation marks if it contains spaces.
`-o` output-file	Specify the output file name for new CRL. Bracket the output-file string with quotation marks if it contains spaces. If this argument is not used the output destination defaults to standard output.
`-t` crl-type	Specify type of CRL. possible types are: 0 - SEC_KRL_TYPE, 1 - SEC_CRL_TYPE. This option is obsolete
`-u` url	Specify the url.

CRL Generation script syntax:

CRL generation script file has the following syntax:

Line with comments should have # as a first symbol of a line
Set "this update" or "next update" CRL fields:

update=YYYYMMDDhhmmssZ
nextupdate=YYYYMMDDhhmmssZ

Field "next update" is optional. Time should be in GeneralizedTime format (YYYYMMDDhhmmssZ).
For example: 20050204153000Z
Add an extension to a CRL or a crl certificate entry:

addext extension-name critical/non-critical [arg1[arg2 ...]]

Where:

extension-name: string value of a name of known extensions.
critical/non-critical: is 1 when extension is critical and 0 otherwise.
arg1, arg2: specific to extension type extension parameters

addext uses the range that was set earlier by addcert and will install an extension to every cert entries within the range.
See "Implemented extensions" for more information regarding extensions and theirs parameters.
Add certificate entries(s) to CRL:

addcert range date

Where:

range: two integer values separated by dash: range of certificates that will be added by this command. dash is used as a delimiter. Only one cert will be added if there is no delimiter.
date: revocation date of a cert. Date should be represented in GeneralizedTime format (YYYYMMDDhhmmssZ).
Remove certificate entry(s) from CRL

rmcert range

Where:

range: two integer values separated by dash: range of certificates that will be added by this command. dash is used as a delimiter. Only one cert will be added if there is no delimiter.
Change range of certificate entry(s) in CRL

range new-range

Where:

new-range: two integer values separated by dash: range of certificates that will be added by this command. dash is used as a delimiter. Only one cert will be added if there is no delimiter.

Implemented Extensions

The extensions defined for CRL provide methods for associating additional attributes with CRLs of theirs entries. For more information see

RFC #3280

Add The Authority Key Identifier extension:
The authority key identifier extension provides a means of identifying the public key corresponding to the private key used to sign a CRL.

authKeyId critical [key-id | dn cert-serial]

Where:

authKeyIdent: identifies the name of an extension
critical: value of 1 of 0. Should be set to 1 if this extension is critical or 0 otherwise.
key-id: key identifier represented in octet string. dn:: is a CA distinguished name cert-serial: authority certificate serial number.
Add Issuer Alternative Name extension:
The issuer alternative names extension allows additional identities to be associated with the issuer of the CRL. Defined options include an rfc822 name (electronic mail address), a DNS name, an IP address, and a URI.

issuerAltNames non-critical name-list

Where:

subjAltNames: identifies the name of an extension
should be set to 0 since this is non-critical extension
name-list: comma separated list of names
Add CRL Number extension:
The CRL number is a non-critical CRL extension which conveys a monotonically increasing sequence number for a given CRL scope and CRL issuer. This extension allows users to easily determine when a particular CRL supersedes another CRL

crlNumber non-critical number

Where:

crlNumber: identifies the name of an extension
critical: should be set to 0 since this is non-critical extension
number: value of long which identifies the sequential number of a CRL.
Add Revocation Reason Code extension:
The reasonCode is a non-critical CRL entry extension that identifies the reason for the certificate revocation.

reasonCode non-critical code

Where:

reasonCode: identifies the name of an extension
non-critical: should be set to 0 since this is non-critical extension
code: the following codes are available:

unspecified (0),
keyCompromise (1),
cACompromise (2),
affiliationChanged (3),
superseded (4),
cessationOfOperation (5),
certificateHold (6),
removeFromCRL (8),
privilegeWithdrawn (9),
aACompromise (10)
Add Invalidity Date extension:
The invalidity date is a non-critical CRL entry extension that provides the date on which it is known or suspected that the private key was compromised or that the certificate otherwise became invalid.

invalidityDate non-critical date

Where:

crlNumber: identifies the name of an extension
non-critical: should be set to 0 since this is non-critical extension date: invalidity date of a cert. Date should be represented in GeneralizedTime format (YYYYMMDDhhmmssZ).

Usage

The Certificate Revocation List Management Tool's capabilities are grouped as follows, using these combinations of options and arguments. Options and arguments in square brackets are optional, those without square brackets are required.

Creating or modifying a CRL:

-G|-M -c crl-gen-file -n nickname [-i crl] [-u url] [-d keydir] [-P dbprefix] [-l alg] [-a] [-B]

Listing all CRls or a named CRL:

-L [-n crl-name] [-d krydir]

Deleting CRL from db:

crlutil -D -n nickname [-d keydir] [-P dbprefix]

Erasing CRLs from db:

crlutil -E [-d keydir] [-P dbprefix]

Import CRL from file:

crlutil -I -i crl [-t crlType] [-u url] [-d keydir] [-P dbprefix] [-B]

Examples

Creating a New CRL
Listing CRLs in a Database
Deleting CRL from a Database
Importing CRL into a Database
Modifiying CRL in a Database

Creating a New CRL

This example creates a new CRL and importing it in to a Database in the specified directory:

crlutil -G -d certdir

-n

cert-nickname -c crl-script-file

crlutil -G -d certdir-ncert-nickname<<EOF update=20050204153000Z addcert 34-40 20050104153000Z EOF

Where cert-nickname is the name the new CRL will be signed with.




Listing CRLs in a Database



This example lists all the CRLs in the NSS database in the specified directory: 

crlutil -L -d certdir 

The CRL Management Tool displays output similar to the following: 

CRL
Name              CRL
Type

CN=NSS Test CA,O=BOGUS NSS,L=Mountain
View,ST=California,C=US  CRL

CN=John Smith,O=Netscape,L=Mountain View,ST=California,C=US  CRL
To view a particular CRL user should specify -n nickname parameter.

crlutil -L -d certdir -n  nickname


CRL Info:

:

    Version: 2 (0x1)

    Signature Algorithm: PKCS #1 MD5 With RSA Encryption

    Issuer: "CN=NSS Test CA,O=BOGUS NSS,L=Mountain View,ST=California,C=US"

    This Update: Wed Feb 23 12:08:38 2005

    Entry (1):

        Serial Number: 40 (0x28)

        Revocation Date: Wed Feb 23 12:08:10 2005

    Entry (2):

        Serial Number: 42 (0x2a)

        Revocation Date: Wed Feb 23 12:08:40 2005







Deleting CRL from a Database


This example deletes CRL from a database in the specified directory: 

crlutil -D -n nickname -d certdir 




Importing CRL into a Database


This example imports CRL into a database: 

crlutil -I -i crl-file -d certdir 

File should has binary format of ASN.1 encoded CRL data.



Modifying CRL in a Database



This example modifies a new CRL and importing it in to a Database in the specified directory: 

crlutil -G -d certdir -n
cert-nickname -c crl-script-file
or

crlutil -M -d certdir -n
cert-nickname <<EOF

update=20050204153000Z

addcert 40-60 20050105153000Z

EOF
The CRL Management Tool extracts existing CRL from a database, will modify and sign
with certificate cert-nickname and will store it in database.
To modify while importing CRL from file user should supply
-i import-crl-file option.