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certutil — Manage keys and certificate in | certutil — Manage keys and certificate in the NSS database. | ||
Synopsis | Synopsis | ||
Latest revision as of 01:08, 3 October 2010
Name
certutil — Manage keys and certificate in the NSS database.
Synopsis
certutil [options] arguments
Description
The Certificate Database Tool, certutil, is a command-line utility that can create and modify certificate and key database files. It can also list, generate, modify, or delete certificates within the database, create or change the password, generate new public and private key pairs, display the contents of the key database, or delete key pairs within the key database.
The key and certificate management process generally begins with creating keys in the key database, then generating and managing certificates in the certificate database. This document discusses certificate and key database management. For information security module database management, see the modutil manpages.
Options and Arguments
Running certutil always requires one (and only one) option to specify the type of certificate operation. Each option may take arguments, anywhere from none to multiple arguments. Run the command option and -H to see the arguments available for each command option.
Options
Options specify an action and are uppercase.
-A
Add an existing certificate to a certificate database.
The certificate database should already exist; if one is
not present, this option will initialize one by default.
-B
Run a series of commands from the specified batch file.
This requires the -i argument.
-C
Create a new binary certificate file from a binary
certificate request file. Use the -i argument to specify
the certificate request file. If this argument is not
used, certutil prompts for a filename.
-D
Delete a certificate from the certificate database.
-E
Add an email certificate to the certificate database.
-F
Delete a private key from a key database. Specify the
key to delete with the -n argument. Specify the database
from which to delete the key with the -d argument. Use
the -k argument to specify explicitly whether to delete
a DSA, RSA, or ECC key. If you don't use the -k
argument, the option looks for an RSA key matching the
specified nickname.
When you delete keys, be sure to also remove any
certificates associated with those keys from the
certificate database, by using -D. Some smart cards (for
example, the Litronic card) do not let you remove a
public key you have generated. In such a case, only the
private key is deleted from the key pair. You can
display the public key with the command certutil -K -h
tokenname.
-G
Generate a new public and private key pair within a key
database. The key database should already exist; if one
is not present, this option will initialize one by
default. Some smart cards (for example, the Litronic
card) can store only one key pair. If you create a new
key pair for such a card, the previous pair is
overwritten.
-H
Display a list of the options and arguments used by the
Certificate Database Tool.
-K
List the key ID of keys in the key database. A key ID is
the modulus of the RSA key or the publicValue of the DSA
key. IDs are displayed in hexadecimal ("0x" is not
shown).
-L
List all the certificates, or display information about
a named certificate, in a certificate database. Use the
-h tokenname argument to specify the certificate
database on a particular hardware or software token.
-M
Modify a certificate's trust attributes using the values
of the -t argument.
-N
Create new certificate and key databases.
-O
Print the certificate chain.
-R
Create a certificate request file that can be submitted
to a Certificate Authority (CA) for processing into a
finished certificate. Output defaults to standard out
unless you use -o output-file argument. Use the -a
argument to specify ASCII output.
-S
Create an individual certificate and add it to a
certificate database.
-T
Reset the key database or token.
-U
List all available modules or print a single named
module.
-V
Check the validity of a certificate and its attributes.
-W
Change the password to a key database.
--merge
Merge a source database into the target database. This
is used to merge legacy NSS databases (cert8.db and
key3.db) into the newer SQLite databases (cert9.db and
key4.db).
--upgrade-merge
Upgrade an old database and merge it into a new
database. This is used to migrate legacy NSS databases
(cert8.db and key3.db) into the newer SQLite databases
(cert9.db and key4.db).
Arguments
Option arguments modify an action and are lowercase.
-a
Use ASCII format or allow the use of ASCII format for
input or output. This formatting follows RFC 1113. For
certificate requests, ASCII output defaults to standard
output unless redirected.
-b validity-time
Specify a time at which a certificate is required to be
valid. Use when checking certificate validity with the
-V option. The format of the validity-time argument is
YYMMDDHHMMSS[+HHMM|-HHMM|Z], which allows offsets to be
set relative to the validity end time. Specifying
seconds (SS) is optional. When specifying an explicit
time, use a Z at the end of the term, YYMMDDHHMMSSZ, to
close it. When specifying an offset time, use
YYMMDDHHMMSS+HHMM or YYMMDDHHMMSS-HHMM for adding or
subtracting time, respectively.
If this option is not used, the validity check defaults
to the current system time.
-c issuer
Identify the certificate of the CA from which a new
certificate will derive its authenticity. Use the exact
nickname or alias of the CA certificate, or use the CA's
email address. Bracket the issuer string with quotation
marks if it contains spaces.
-d [sql:]directory
Specify the database directory containing the
certificate and key database files.
certutil supports two types of databases: the legacy
security databases (cert8.db, key3.db, and secmod.db)
and new SQLite databases (cert9.db, key4.db, and
pkcs11.txt). If the prefix sql: is not used, then the
tool assumes that the given databases are in the old
format.
-e
Check a certificate's signature during the process of
validating a certificate.
-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.
-g keysize
Set a key size to use when generating new public and
private key pairs. The minimum is 512 bits and the
maximum is 8192 bits. The default is 1024 bits. Any size
between the minimum and maximum is allowed.
-h tokenname
Specify the name of a token to use or act on. Unless
specified otherwise the default token is an internal
slot (specifically, internal slot 2). This slot can also
be explicitly named with the string "internal". An
internal slots is a virtual slot maintained in software,
rather than a hardware device. Internal slot 2 is used
by key and certificate services. Internal slot 1 is used
by cryptographic services.
-i input_file
Pass an input file to the command. Depending on the
command option, an input file can be a specific
certificate, a certificate request file, or a batch file
of commands.
-k rsa|dsa|ec|all
Specify the type of a key. The valid options are RSA,
DSA, ECC, or all. The default value is rsa. Specifying
the type of key can avoid mistakes caused by duplicate
nicknames.
-k key-type-or-id
Specify the type or specific ID of a key. Giving a key
type generates a new key pair; giving the ID of an
existing key reuses that key pair (which is required to
renew certificates).
-l
Display detailed information when validating a
certificate with the -V option.
-m serial-number
Assign a unique serial number to a certificate being
created. This operation should be performed by a CA. The
default serial number is 0 (zero). Serial numbers are
limited to integers.
-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 certificates or
binary certificate requests. 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.
-P dbPrefix
Specify the prefix used on the certificate and key
database file. This option is provided as a special
case. Changing the names of the certificate and key
databases is not recommended.
-p phone
Specify a contact telephone number to include in new
certificates or certificate requests. Bracket this
string with quotation marks if it contains spaces.
-q pqgfile
Read an alternate PQG value from the specified file when
generating DSA key pairs. If this argument is not used,
certutil generates its own PQG value. PQG files are
created with a separate DSA utility.
-q curve-name
Set the elliptic curve name to use when generating ECC
key pairs. A complete list of ECC curves is given in the
help (-H).
-r
Display a certificate's binary DER encoding when listing
information about that certificate with the -L option.
-s subject
Identify a particular certificate owner for new
certificates or certificate requests. Bracket this
string with quotation marks if it contains spaces. The
subject identification format follows RFC #1485.
-t trustargs
Specify the trust attributes to modify in an existing
certificate or to apply to a certificate when creating
it or adding it to a database. There are three available
trust categories for each certificate, expressed in the
order SSL, email, object signing for each trust setting.
In each category position, use none, any, or all of the
attribute codes:
+ p - Valid peer
+ P - Trusted peer (implies p)
+ c - Valid CA
+ T - Trusted CA to issue client certificates (implies
c)
+ C - Trusted CA to issue server certificates (SSL only)
(implies c)
+ u - Certificate can be used for authentication or
signing
+ w - Send warning (use with other attributes to include
a warning when the certificate is used in that
context)
The attribute codes for the categories are separated by
commas, and the entire set of attributes enclosed by
quotation marks. For example:
-t "TCu,Cu,Tuw"
Use the -L option to see a list of the current
certificates and trust attributes in a certificate
database.
-u certusage
Specify a usage context to apply when validating a
certificate with the -V option.
The contexts are the following:
+ C (as an SSL client)
+ V (as an SSL server)
+ S (as an email signer)
+ R (as an email recipient)
+ O (as an OCSP status responder)
+ J (as an object signer)
-v valid-months
Set the number of months a new certificate will be
valid. The validity period begins at the current system
time unless an offset is added or subtracted with the -w
option. If this argument is not used, the default
validity period is three months. When this argument is
used, the default three-month period is automatically
added to any value given in the valid-month argument.
For example, using this option to set a value of 3 would
cause 3 to be added to the three-month default, creating
a validity period of six months. You can use negative
values to reduce the default period. For example,
setting a value of -2 would subtract 2 from the default
and create a validity period of one month.
-w offset-months
Set an offset from the current system time, in months,
for the beginning of a certificate's validity period.
Use when creating the certificate or adding it to a
database. Express the offset in integers, using a minus
sign (-) to indicate a negative offset. If this argument
is not used, the validity period begins at the current
system time. The length of the validity period is set
with the -v argument.
-X
Force the key and certificate database to open in
read-write mode. This is used with the -U and -L command
options.
-x
Use certutil to generate the signature for a certificate
being created or added to a database, rather than
obtaining a signature from a separate CA.
-y exp
Set an alternate exponent value to use in generating a
new RSA public key for the database, instead of the
default value of 65537. The available alternate values
are 3 and 17.
-z noise-file
Read a seed value from the specified file to generate a
new private and public key pair. This argument makes it
possible to use hardware-generated seed values or
manually create a value from the keyboard. The minimum
file size is 20 bytes.
-0 SSO_password
Set a site security officer password on a token.
-1 | --keyUsage keyword,keyword
Set a Netscape Certificate Type Extension in the
certificate. There are several available keywords:
+ digital signature
+ nonRepudiation
+ keyEncipherment
+ dataEncipherment
+ keyAgreement
+ certSigning
+ crlSigning
+ critical
-2
Add a basic constraint extension to a certificate that
is being created or added to a database. This extension
supports the certificate chain verification process.
certutil prompts for the certificate constraint
extension to select.
X.509 certificate extensions are described in RFC 5280.
-3
Add an authority key ID extension to a certificate that
is being created or added to a database. This extension
supports the identification of a particular certificate,
from among multiple certificates associated with one
subject name, as the correct issuer of a certificate.
The Certificate Database Tool will prompt you to select
the authority key ID extension.
X.509 certificate extensions are described in RFC 5280.
-4
Add a CRL distribution point extension to a certificate
that is being created or added to a database. This
extension identifies the URL of a certificate's
associated certificate revocation list (CRL). certutil
prompts for the URL.
X.509 certificate extensions are described in RFC 5280.
-5 | --nsCertType keyword,keyword
Add a Netscape certificate type extension to a
certificate that is being created or added to the
database. There are several available keywords:
+ sslClient
+ sslServer
+ smime
+ objectSigning
+ sslCA
+ smimeCA
+ objectSigningCA
+ critical
X.509 certificate extensions are described in RFC 5280.
-6 | --extKeyUsage keyword,keyword
Add an extended key usage extension to a certificate
that is being created or added to the database. Several
keywords are available:
+ serverAuth
+ clientAuth
+ codeSigning
+ emailProtection
+ timeStamp
+ ocspResponder
+ stepUp
+ critical
X.509 certificate extensions are described in RFC 5280.
-7 emailAddrs
Add a comma-separated list of email addresses to the
subject alternative name extension of a certificate or
certificate request that is being created or added to
the database. Subject alternative name extensions are
described in Section 4.2.1.7 of RFC 3280.
-8 dns-names
Add a comma-separated list of DNS names to the subject
alternative name extension of a certificate or
certificate request that is being created or added to
the database. Subject alternative name extensions are
described in Section 4.2.1.7 of RFC 3280.
--extAIA
Add the Authority Information Access extension to the
certificate. X.509 certificate extensions are described
in RFC 5280.
--extSIA
Add the Subject Information Access extension to the
certificate. X.509 certificate extensions are described
in RFC 5280.
--extCP
Add the Certificate Policies extension to the
certificate. X.509 certificate extensions are described
in RFC 5280.
--extPM
Add the Policy Mappings extension to the certificate.
X.509 certificate extensions are described in RFC 5280.
--extPC
Add the Policy Constraints extension to the certificate.
X.509 certificate extensions are described in RFC 5280.
--extIA
Add the Inhibit Any Policy Access extension to the
certificate. X.509 certificate extensions are described
in RFC 5280.
--extSKID
Add the Subject Key ID extension to the certificate.
X.509 certificate extensions are described in RFC 5280.
--source-dir certdir
Identify the certificate database directory to upgrade.
--source-prefix certdir
Give the prefix of the certificate and key databases to
upgrade.
--upgrade-id uniqueID
Give the unique ID of the database to upgrade.
--upgrade-token-name name
Set the name of the token to use while it is being
upgraded.
-@ pwfile
Give the name of a password file to use for the database
being upgraded.
Usage and Examples
Most of the command options in the examples listed here have more arguments available. The arguments included in these examples are the most common ones or are used to illustrate a specific scenario. Use the -H option to show the complete list of arguments for each command option.
Creating New Security Databases
Certificates, keys, and security modules related to managing
certificates are stored in three related databases:
* cert8.db or cert9.db
* key3.db or key4.db
* secmod.db or pkcs11.txt
These databases must be created before certificates or keys can be generated.
certutil -N -d [sql:]directory
Creating a Certificate Request
A certificate request contains most or all of the information that is used to generate the final certificate. This request is submitted separately to a certificate authority and is then approved by some mechanism (automatically or by human review). Once the request is approved, then the certificate is generated.
$ certutil -R -k key-type-or-id [-q pqgfile|curve-name] -g key-size -s s ubject [-h tokenname] -d [sql:]directory [-p phone] [-o output-file] [-a ]
The -R command options requires four arguments:
* -k to specify either the key type to generate or, when
renewing a certificate, the existing key pair to use
* -g to set the keysize of the key to generate
* -s to set the subject name of the certificate
* -d to give the security database directory
The new certificate request can be output in ASCII format (-a) or can be written to a specified file (-o).
For example:
$ certutil -R -k ec -q nistb409 -g 512 -s "CN=John Smith,O=Example Corp, L=Mountain View,ST=California,C=US" -d sql:/home/my/sharednssdb -p 650-5 55-0123 -a -o cert.cer
Generating key. This may take a few moments...
Certificate request generated by Netscape
Phone: 650-555-0123
Common Name: John Smith
Email: (not ed)
Organization: Example Corp
State: California
Country: US
BEGIN NEW CERTIFICATE REQUEST-----
MIIBIDCBywIBADBmMQswCQYDVQQGEwJVUzETMBEGA1UECBMKQ2FsaWZvcm5pYTEW MBQGA1UEBxMNTW91bnRhaW4gVmlldzEVMBMGA1UEChMMRXhhbXBsZSBDb3JwMRMw EQYDVQQDEwpKb2huIFNtaXRoMFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBAMVUpDOZ KmHnOx7reP8Cc0Lk+fFWEuYIDX9W5K/BioQOKvEjXyQZhit9aThzBVMoSf1Y1S8J CzdUbCg1+IbnXaECAwEAAaAAMA0GCSqGSIb3DQEBBQUAA0EAryqZvpYrUtQ486Ny qmtyQNjIi1F8c1Z+TL4uFYlMg8z6LG/J/u1E5t1QqB5e9Q4+BhRbrQjRR1JZx3tB 1hP9Gg==
END NEW CERTIFICATE REQUEST-----
Creating a Certificate
A valid certificate must be issued by a trusted CA. This can be done by specifying a CA certificate (-c) that is stored in the certificate database. If a CA key pair is not available, you can create a self-signed certificate using the -x argument with the -S command option.
$ certutil -S -k rsa|dsa|ec -n certname -s subject [-c issuer |-x] -t tr ustargs -d [sql:]directory [-m serial-number] [-v valid-months] [-w offs et-months] [-p phone] [-1] [-2] [-3] [-4] [-5 keyword] [-6 keyword] [-7 emailAddress] [-8 dns-names] [--extAIA] [--extSIA] [--extCP] [--extPM] [ --extPC] [--extIA] [--extSKID]
The series of numbers and --ext* options set certificate extensions that can be added to the certificate when it is generated by the CA.
For example, this creates a self-signed certificate:
$ certutil -S -s "CN=Example CA" -n my-ca-cert -x -t "C,C,C" -1 -2 -5 -m
3650
From there, new certificates can reference the self-signed certificate:
$ certutil -S -s "CN=My Server Cert" -n my-server-cert -c "my-ca-cert" - t "u,u,u" -1 -5 -6 -8 -m 730
Generating a Certificate from a Certificate Request
When a certificate request is created, a certificate can be generated by using the request and then referencing a certificate authority signing certificate (the issuer specified in the -c argument). The issuing certificate must be in the certificate database in the specified directory.
certutil -C -c issuer -i cert-request-file -o output-file [-m serial-num ber] [-v valid-months] [-w offset-months] -d [sql:]directory [-1] [-2] [ -3] [-4] [-5 keyword] [-6 keyword] [-7 emailAddress] [-8 dns-names]
For example:
$ certutil -C -c "my-ca-cert" -i /home/certs/cert.req -o cert.cer -m 010
-v 12 -w 1 -d sql:/home/my/sharednssdb -1 nonRepudiation,dataEncipherme
nt -5 sslClient -6 clientAuth -7 jsmith@example.com
Generating Key Pairs
Key pairs are generated automatically with a certificate request or certificate, but they can also be generated independently using the -G command option.
certutil -G -d [sql:]directory | -h tokenname -k key-type -g key-size [- y exponent-value] -q pqgfile|curve-name
For example:
$ certutil -G -h lunasa -k ec -g 256 -q sect193r2
Listing Certificates
The -L command option lists all of the certificates listed in the certificate database. The path to the directory (-d) is required.
$ certutil -L -d sql:/home/my/sharednssdb
Certificate Nickname Trust Attri butes
SSL,S/MIME,
JAR/XPI
CA Administrator of Instance pki-ca1's Example Domain ID u,u,u TPS Administrator's Example Domain ID u,u,u Google Internet Authority ,, Certificate Authority - Example Domain CT,C,C
Using additional arguments with -L can return and print the information for a single, specific certificate. For example, the -n argument passes the certificate name, while the -a argument prints the certificate in ASCII format:
$ certutil -L -d sql:/home/my/sharednssdb -a -n "Certificate Authority -
Example Domain"
BEGIN CERTIFICATE-----
MIIDmTCCAoGgAwIBAgIBATANBgkqhkiG9w0BAQUFADA5MRcwFQYDVQQKEw5FeGFt cGxlIERvbWFpbjEeMBwGA1UEAxMVQ2VydGlmaWNhdGUgQXV0aG9yaXR5MB4XDTEw MDQyOTIxNTY1OFoXDTEyMDQxODIxNTY1OFowOTEXMBUGA1UEChMORXhhbXBsZSBE b21haW4xHjAcBgNVBAMTFUNlcnRpZmljYXRlIEF1dGhvcml0eTCCASIwDQYJKoZI hvcNAQEBBQADggEPADCCAQoCggEBAO/bqUli2KwqXFKmMMG93KN1SANzNTXA/Vlf Tmrih3hQgjvR1ktIY9aG6cB7DSKWmtHp/+p4PUCMqL4ZrSGt901qxkePyZ2dYmM2 RnelK+SEUIPiUtoZaDhNdiYsE/yuDE8vQWj0vHCVL0w72qFUcSQ/WZT7FCrnUIUI udeWnoPSUn70gLhcj/lvxl7K9BHyD4Sq5CzktwYtFWLiiwV+ZY/Fl6JgbGaQyQB2 bP4iRMfloGqsxGuB1evWVDF1haGpFDSPgMnEPSLg3/3dXn+HDJbZ29EU8/xKzQEb 3V0AHKbu80zGllLEt2Zx/WDIrgJEN9yMfgKFpcmL+BvIRsmh0VsCAwEAAaOBqzCB qDAfBgNVHSMEGDAWgBQATgxHQyRUfKIZtdp55bZlFr+tFzAPBgNVHRMBAf8EBTAD AQH/MA4GA1UdDwEB/wQEAwIBxjAdBgNVHQ4EFgQUAE4MR0MkVHyiGbXaeeW2ZRa/ rRcwRQYIKwYBBQUHAQEEOTA3MDUGCCsGAQUFBzABhilodHRwOi8vbG9jYWxob3N0 LmxvY2FsZG9tYWluOjkxODAvY2Evb2NzcDANBgkqhkiG9w0BAQUFAAOCAQEAi8Gk L3XO43u7/TDOeEsWPmq+jZsDZ3GZ85Ajt3KROLWeKVZZZa2E2Hnsvf2uXbk5amKe lRxdSeRH9g85pv4KY7Z8xZ71NrI3+K3uwmnqkc6t0hhYb1mw/gx8OAAoluQx3biX JBDxjI73Cf7XUopplHBjjiwyGIJUO8BEZJ5L+TF4P38MJz1snLtzZpEAX5bl0U76 bfu/tZFWBbE8YAWYtkCtMcalBPj6jn2WD3M01kGozW4mmbvsj1cRB9HnsGsqyHCu U0ujlL1H/RWcjn607+CTeKH9jLMUqCIqPJNOa+kq/6F7NhNRRiuzASIbZc30BZ5a nI7q5n1USM3eWQlVXw==
END CERTIFICATE-----
Listing Keys
Keys are the original material used to encrypt certificate data. The keys generated for certificates are stored separately, in the key database.
To list all keys in the database, use the -K command option and the (required) -d argument to give the path to the directory.
$ certutil -K -d sql:/home/my/sharednssdb certutil: Checking token "NSS Certificate DB" in slot "NSS User Private Key and Certificate Services " < 0> rsa 455a6673bde9375c2887ec8bf8016b3f9f35861d Thawte Freemail
Member's Thawte Consulting (Pty) Ltd. ID
< 1> rsa 40defeeb522ade11090eacebaaf1196a172127df Example Domain Administrator Cert < 2> rsa 1d0b06f44f6c03842f7d4f4a1dc78b3bcd1b85a5 John Smith user
cert
There are ways to narrow the keys listed in the search results:
* To return a specific key, use the -n name argument with the
name of the key.
* If there are multiple security devices loaded, then the -h
tokenname argument can search a specific token or all
tokens.
* If there are multiple key types available, then the -k
key-type argument can search a specific type of key, like
RSA, DSA, or ECC.
Listing Security Modules
The devices that can be used to store certificates -- both internal databases and external devices like smart cards -- are recognized and used by loading security modules. The -U command option lists all of the security modules listed in the secmod.db database. The path to the directory (-d) is required.
$ certutil -U -d sql:/home/my/sharednssdb
slot: NSS User Private Key and Certificate Services
token: NSS Certificate DB
slot: NSS Internal Cryptographic Services
token: NSS Generic Crypto Services
Adding Certificates to the Database
Existing certificates or certificate requests can be added manually to the certificate database, even if they were generated elsewhere. This uses the -A command option.
certutil -A -n certname -t trustargs -d [sql:]directory [-a] [-i input-f ile]
For example:
$ certutil -A -n "CN=My SSL Certificate" -t "u,u,u" -d sql:/home/my/shar ednssdb -i /home/example-certs/cert.cer
A related command option, -E, is used specifically to add email certificates to the certificate database. The -E command has the same arguments as the -A command. The trust arguments for certificates have the format SSL,S/MIME,Code-signing, so the middle trust settings relate most to email certificates (though the others can be set). For example:
$ certutil -E -n "CN=John Smith Email Cert" -t ",Pu," -d sql:/home/my/sh arednssdb -i /home/example-certs/email.cer
Deleting Certificates to the Database
Certificates can be deleted from a database using the -D option. The only required options are to give the security database directory and to identify the certificate nickname.
certutil -D -d [sql:]directory -n "nickname"
For example:
$ certutil -D -d sql:/home/my/sharednssdb -n "my-ssl-cert"
Validating Certificates
A certificate contains an expiration date in itself, and expired certificates are easily rejected. However, certificates can also be revoked before they hit their expiration date. Checking whether a certificate has been revoked requires validating the certificate. Validation can also be used to ensure that the certificate is only used for the purposes it was initially issued for. Validation is carried out by the -V command option.
certutil -V -n certificate-name [-b time] [-e] [-u cert-usage] -d [sql:] directory
For example, to validate an email certificate:
$ certutil -V -n "John Smith's Email Cert" -e -u S,R -d sql:/home/my/sha rednssdb
Modifying Certificate Trust Settings
The trust settings (which relate to the operations that a certificate is allowed to be used for) can be changed after a certificate is created or added to the database. This is especially useful for CA certificates, but it can be performed for any type of certificate.
certutil -M -n certificate-name -t trust-args -d [sql:]directory
For example:
$ certutil -M -n "My CA Certificate" -d sql:/home/my/sharednssdb -t "CTu ,CTu,CTu"
Printing the Certificate Chain
Certificates can be issued in chains because every certificate authority itself has a certificate; when a CA issues a certificate, it essentially stamps that certificate with its own fingerprint. The -O prints the full chain of a certificate, going from the initial CA (the root CA) through ever intermediary CA to the actual certificate. For example, for an email certificate with two CAs in the chain:
$ certutil -d sql:/home/my/sharednssdb -O -n "jsmith@example.com" "Builtin Object Token:Thawte Personal Freemail CA" [E=personal-freemail@ thawte.com,CN=Thawte Personal Freemail CA,OU=Certification Services Divi sion,O=Thawte Consulting,L=Cape Town,ST=Western Cape,C=ZA]
"Thawte Personal Freemail Issuing CA - Thawte Consulting" [CN=Thawte P
ersonal Freemail Issuing CA,O=Thawte Consulting (Pty) Ltd.,C=ZA]
"(null)" [E=jsmith@example.com,CN=Thawte Freemail Member]
Resetting a Token
The device which stores certificates -- both external hardware devices and internal software databases -- can be blanked and reused. This operation is performed on the device which stores the data, not directly on the security databases, so the location must be referenced through the token name (-h) as well as any directory path. If there is no external token used, the default value is internal.
certutil -T -d [sql:]directory -h token-name -0 security-officer-passwor d
Many networks have dedicated personnel who handle changes to security tokens (the security officer). This person must supply the password to access the specified token. For example:
$ certutil -T -d sql:/home/my/sharednssdb -h nethsm -0 secret
Upgrading or Merging the Security Databases
Many networks or applications may be using older BerkeleyDB versions of the certificate database (cert8.db). Databases can be upgraded to the new SQLite version of the database (cert9.db) using the --upgrade-merge command option or existing databases can be merged with the new cert9.db databases using the ---merge command.
The --upgrade-merge command must give information about the original database and then use the standard arguments (like -d) to give the information about the new databases. The command also requires information that the tool uses for the process to upgrade and write over the original database.
certutil --upgrade-merge -d [sql:]directory [-P dbprefix] --source-dir d irectory --source-prefix dbprefix --upgrade-id id --upgrade-token-name n ame [-@ password-file]
For example:
$ certutil --upgrade-merge -d sql:/home/my/sharednssdb --source-dir /opt /my-app/alias/ --source-prefix serverapp- --upgrade-id 1 --upgrade-token -name internal
The --merge command only requires information about the location of the original database; since it doesn't change the format of the database, it can write over information without performing interim step.
certutil --merge -d [sql:]directory [-P dbprefix] --source-dir directory
--source-prefix dbprefix [-@ password-file]
For example:
$ certutil --merge -d sql:/home/my/sharednssdb --source-dir /opt/my-app/ alias/ --source-prefix serverapp-
Running certutil Commands from a Batch File
A series of commands can be run sequentially from a text file with the -B command option. The only argument for this specifies the input file.
$ certutil -B -i /path/to/batch-file
NSS Database Types
NSS originally used BerkeleyDB databases to store security
information. The last versions of these legacy databases are:
* cert8.db for certificates
* key3.db for keys
* secmod.db for PKCS #11 module information
BerkeleyDB has performance limitations, though, which prevent it from being easily used by multiple applications simultaneously. NSS has some flexibility that allows applications to use their own, independent database engine while keeping a shared database and working around the access issues. Still, NSS requires more flexibility to provide a truly shared security database.
In 2009, NSS introduced a new set of databases that are SQLite
databases rather than BerkleyDB. These new databases provide
more accessibility and performance:
* cert9.db for certificates
* key4.db for keys
* pkcs11.txt, which is listing of all of the PKCS #11 modules
contained in a new subdirectory in the security databases
directory
Because the SQLite databases are designed to be shared, these are the shared database type. The shared database type is preferred; the legacy format is included for backward compatibility.
By default, the tools (certutil, pk12util, modutil) assume that the given security databases follow the more common legacy type. Using the SQLite databases must be manually specified by using the sql: prefix with the given security directory. For example:
$ certutil -L -d sql:/home/my/sharednssdb
To set the shared database type as the default type for the tools, set the NSS_DEFAULT_DB_TYPE environment variable to sql:
export NSS_DEFAULT_DB_TYPE="sql"
This line can be set added to the ~/.bashrc file to make the change permanent.
Most applications do not use the shared database by default,
but they can be configured to use them. For example, this
how-to article covers how to configure Firefox and Thunderbird
to use the new shared NSS databases:
* https://wiki.mozilla.org/NSS_Shared_DB_Howto
For an engineering draft on the changes in the shared NSS
databases, see the NSS project wiki:
* https://wiki.mozilla.org/NSS_Shared_DB
See Also
pk12util (1)
modutil (1)
certutil has arguments or operations that use features defined
in several IETF RFCs.
* http://tools.ietf.org/html/rfc5280
* http://tools.ietf.org/html/rfc1113
* http://tools.ietf.org/html/rfc1485
The NSS wiki has information on the new database design and how
to configure applications to use it.
* https://wiki.mozilla.org/NSS_Shared_DB_Howto
* https://wiki.mozilla.org/NSS_Shared_DB
Additional Resources
For information about NSS and other tools related to NSS (like JSS), check out the NSS project wiki at http://www.mozilla.org/projects/security/pki/nss/. The NSS site relates directly to NSS code changes and releases.
Mailing lists: https://lists.mozilla.org/listinfo/dev-tech-crypto
IRC: Freenode at #dogtag-pki
Authors
The NSS tools were written and maintained by developers with Netscape, Red Hat, and Sun.
Authors: Elio Maldonado <emaldona@redhat.com>, Deon Lackey <dlackey@redhat.com>.
Copyright
(c) 2010, Red Hat, Inc. Licensed under the GNU Public License version 2.