keytool(1) Security Tools keytool(1)NAMEkeytool - Manages a keystore (database) of cryptographic keys, X.509
certificate chains, and trusted certificates.
SYNOPSISkeytool [commands]
commands
See Commands. These commands are categorized by task as follows:
· Create or Add Data to the Keystore
· -gencert
· -genkeypair
· -genseckey
· -importcert
· -importpassword
· Import Contents From Another Keystore
· -importkeystore
· Generate Certificate Request
· -certreq
· Export Data
· -exportcert
· Display Data
· -list
· -printcert
· -printcertreq
· -printcrl
· Manage the Keystore
· -storepasswd
· -keypasswd
· -delete
· -changealias
· Get Help
· -help
DESCRIPTION
The keytool command is a key and certificate management utility. It
enables users to administer their own public/private key pairs and
associated certificates for use in self-authentication (where the user
authenticates himself or herself to other users and services) or data
integrity and authentication services, using digital signatures. The
keytool command also enables users to cache the public keys (in the
form of certificates) of their communicating peers.
A certificate is a digitally signed statement from one entity (person,
company, and so on.), that says that the public key (and some other
information) of some other entity has a particular value. (See
Certificate.) When data is digitally signed, the signature can be
verified to check the data integrity and authenticity. Integrity means
that the data has not been modified or tampered with, and authenticity
means the data comes from whoever claims to have created and signed it.
The keytool command also enables users to administer secret keys and
passphrases used in symmetric encryption and decryption (DES).
The keytool command stores the keys and certificates in a keystore. See
KeyStore aliases.
COMMAND AND OPTION NOTES
See Commands for a listing and description of the various commands.
· All command and option names are preceded by a minus sign (-).
· The options for each command can be provided in any order.
· All items not italicized or in braces or brackets are required to
appear as is.
· Braces surrounding an option signify that a default value will be
used when the option is not specified on the command line. See Option
Defaults. Braces are also used around the -v, -rfc, and -J options,
which only have meaning when they appear on the command line. They do
not have any default values other than not existing.
· Brackets surrounding an option signify that the user is prompted for
the values when the option is not specified on the command line. For
the -keypass option, if you do not specify the option on the command
line, then the keytool command first attempts to use the keystore
password to recover the private/secret key. If this attempt fails,
then the keytool command prompts you for the private/secret key
password.
· Items in italics (option values) represent the actual values that
must be supplied. For example, here is the format of the -printcert
command:
keytool-printcert {-file cert_file} {-v}
When you specify a -printcert command, replace cert_file with the
actual file name, as follows: keytool-printcert -file VScert.cer
· Option values must be put in quotation marks when they contain a
blank (space).
· The -help option is the default. The keytool command is the same as
keytool-help.
OPTION DEFAULTS
The following examples show the defaults for various option values.
-alias "mykey"
-keyalg
"DSA" (when using -genkeypair)
"DES" (when using -genseckey)
-keysize
2048 (when using -genkeypair and -keyalg is "RSA")
1024 (when using -genkeypair and -keyalg is "DSA")
256 (when using -genkeypair and -keyalg is "EC")
56 (when using -genseckey and -keyalg is "DES")
168 (when using -genseckey and -keyalg is "DESede")
-validity 90
-keystore <the file named .keystore in the user's home directory>
-storetype <the value of the "keystore.type" property in the
security properties file, which is returned by the static
getDefaultType method in java.security.KeyStore>
-file
stdin (if reading)
stdout (if writing)
-protected false
In generating a public/private key pair, the signature algorithm
(-sigalg option) is derived from the algorithm of the underlying
private key:
· If the underlying private key is of type DSA, then the -sigalg option
defaults to SHA1withDSA.
· If the underlying private key is of type RSA, then the -sigalg option
defaults to SHA256withRSA.
· If the underlying private key is of type EC, then the -sigalg option
defaults to SHA256withECDSA.
For a full list of -keyalg and -sigalg arguments, see Java Cryptography
Architecture (JCA) Reference Guide at
http://docs.oracle.com/javase/8/docs/technotes/guides/security/crypto/CryptoSpec.html#AppA
COMMON OPTIONS
The -v option can appear for all commands except -help. When the -v
option appears, it signifies verbose mode, which means that more
information is provided in the output.
There is also a -Jjavaoption argument that can appear for any command.
When the -Jjavaoption appears, the specified javaoption string is
passed directly to the Java interpreter. This option does not contain
any spaces. It is useful for adjusting the execution environment or
memory usage. For a list of possible interpreter options, type java -h
or java -X at the command line.
These options can appear for all commands operating on a keystore:
-storetype storetype
This qualifier specifies the type of keystore to be
instantiated.
-keystore keystore
The keystore location.
If the JKS storetype is used and a keystore file does not yet
exist, then certain keytool commands can result in a new
keystore file being created. For example, if keytool-genkeypair
is called and the -keystore option is not specified, the default
keystore file named .keystore in the user's home directory is
created when it does not already exist. Similarly, if the
-keystore ks_file option is specified but ks_file does not
exist, then it is created. For more information on the JKS
storetype, see the KeyStore Implementation section in KeyStore
aliases.
Note that the input stream from the -keystore option is passed
to the KeyStore.load method. If NONE is specified as the URL,
then a null stream is passed to the KeyStore.load method. NONE
should be specified if the keystore is not file-based. For
example, when it resides on a hardware token device.
-storepass[:env| :file] argument
The password that is used to protect the integrity of the
keystore.
If the modifier env or file is not specified, then the password
has the value argument, which must be at least 6 characters
long. Otherwise, the password is retrieved as follows:
· env: Retrieve the password from the environment variable named
argument.
· file: Retrieve the password from the file named argument.
Note: All other options that require passwords, such as -keypass,
-srckeypass, -destkeypass, -srcstorepass, and -deststorepass, accept
the env and file modifiers. Remember to separate the password option
and the modifier with a colon (:).
The password must be provided to all commands that access the keystore
contents. For such commands, when the -storepass option is not provided
at the command line, the user is prompted for it.
When retrieving information from the keystore, the password is
optional. If no password is specified, then the integrity of the
retrieved information cannot be verified and a warning is displayed.
-providerName provider_name
Used to identify a cryptographic service provider's name when
listed in the security properties file.
-providerClass provider_class_name
Used to specify the name of a cryptographic service provider's
master class file when the service provider is not listed in the
security properties file.
-providerArg provider_arg
Used with the -providerClass option to represent an optional
string input argument for the constructor of
provider_class_name.
-protected
Either true or false. This value should be specified as true
when a password must be specified by way of a protected
authentication path such as a dedicated PIN reader.Because there
are two keystores involved in the -importkeystore command, the
following two options -srcprotected and -destprotected are
provided for the source keystore and the destination keystore
respectively.
-ext {name{:critical} {=value}}
Denotes an X.509 certificate extension. The option can be used
in -genkeypair and -gencert to embed extensions into the
certificate generated, or in -certreq to show what extensions
are requested in the certificate request. The option can appear
multiple times. The name argument can be a supported extension
name (see Named Extensions) or an arbitrary OID number. The
value argument, when provided, denotes the argument for the
extension. When value is omitted, that means that the default
value of the extension or the extension requires no argument.
The :critical modifier, when provided, means the extension's
isCritical attribute is true; otherwise, it is false. You can
use :c in place of :critical.
NAMED EXTENSIONS
The keytool command supports these named extensions. The names are not
case-sensitive).
BC or BasicContraints
Values: The full form is: ca:{true|false}[,pathlen:<len>] or
<len>, which is short for ca:true,pathlen:<len>. When <len> is
omitted, you have ca:true.
KU or KeyUsage
Values: usage(,usage)*, where usage can be one of
digitalSignature, nonRepudiation (contentCommitment),
keyEncipherment, dataEncipherment, keyAgreement, keyCertSign,
cRLSign, encipherOnly, decipherOnly. The usage argument can be
abbreviated with the first few letters (dig for
digitalSignature) or in camel-case style (dS for
digitalSignature or cRLS for cRLSign), as long as no ambiguity
is found. The usage values are case-sensitive.
EKU or ExtendedKeyUsage
Values: usage(,usage)*, where usage can be one of
anyExtendedKeyUsage, serverAuth, clientAuth, codeSigning,
emailProtection, timeStamping, OCSPSigning, or any OID string.
The usage argument can be abbreviated with the first few letters
or in camel-case style, as long as no ambiguity is found. The
usage values are case-sensitive.
SAN or SubjectAlternativeName
Values: type:value(,type:value)*, where type can be EMAIL, URI,
DNS, IP, or OID. The value argument is the string format value
for the type.
IAN or IssuerAlternativeName
Values: Same as SubjectAlternativeName.
SIA or SubjectInfoAccess
Values: method:location-type:location-value (,method:location-
type:location-value)*, where method can be timeStamping,
caRepository or any OID. The location-type and location-value
arguments can be any type:value supported by the
SubjectAlternativeName extension.
AIA or AuthorityInfoAccess
Values: Same as SubjectInfoAccess. The method argument can be
ocsp,caIssuers, or any OID.
When name is OID, the value is the hexadecimal dumped DER encoding of
the extnValue for the extension excluding the OCTET STRING type and
length bytes. Any extra character other than standard hexadecimal
numbers (0-9, a-f, A-F) are ignored in the HEX string. Therefore, both
01:02:03:04 and 01020304 are accepted as identical values. When there
is no value, the extension has an empty value field.
A special name honored, used in -gencert only, denotes how the
extensions included in the certificate request should be honored. The
value for this name is a comma separated list of all (all requested
extensions are honored), name{:[critical|non-critical]} (the named
extension is honored, but using a different isCritical attribute) and
-name (used with all, denotes an exception). Requested extensions are
not honored by default.
If, besides the-ext honored option, another named or OID -ext option is
provided, this extension is added to those already honored. However, if
this name (or OID) also appears in the honored value, then its value
and criticality overrides the one in the request.
The subjectKeyIdentifier extension is always created. For non-self-
signed certificates, the authorityKeyIdentifier is created.
Note: Users should be aware that some combinations of extensions (and
other certificate fields) may not conform to the Internet standard. See
Certificate Conformance Warning.
COMMANDS-gencert
{-rfc} {-infile infile} {-outfile outfile} {-alias alias} {-sigalg sigalg}
{-dname dname} {-startdate startdate {-ext ext}* {-validity valDays}
[-keypass keypass] {-keystore keystore} [-storepass storepass]
{-storetype storetype} {-providername provider_name}
{-providerClass provider_class_name {-providerArg provider_arg}}
{-v} {-protected} {-Jjavaoption}
Generates a certificate as a response to a certificate request
file (which can be created by the keytool-certreq command). The
command reads the request from infile (if omitted, from the
standard input), signs it using alias's private key, and outputs
the X.509 certificate into outfile (if omitted, to the standard
output). When-rfc is specified, the output format is
Base64-encoded PEM; otherwise, a binary DER is created.
The sigalg value specifies the algorithm that should be used to
sign the certificate. The startdate argument is the start time
and date that the certificate is valid. The valDays argument
tells the number of days for which the certificate should be
considered valid.
When dname is provided, it is used as the subject of the
generated certificate. Otherwise, the one from the certificate
request is used.
The ext value shows what X.509 extensions will be embedded in
the certificate. Read Common Options for the grammar of -ext.
The -gencert option enables you to create certificate chains.
The following example creates a certificate, e1, that contains
three certificates in its certificate chain.
The following commands creates four key pairs named ca, ca1,
ca2, and e1:
keytool-alias ca -dname CN=CA -genkeypair
keytool-alias ca1 -dname CN=CA -genkeypair
keytool-alias ca2 -dname CN=CA -genkeypair
keytool-alias e1 -dname CN=E1 -genkeypair
The following two commands create a chain of signed
certificates; ca signs ca1 and ca1 signs ca2, all of which are
self-issued:
keytool-alias ca1 -certreq |
keytool-alias ca -gencert -ext san=dns:ca1 |
keytool-alias ca1 -importcert
keytool-alias ca2 -certreq |
$KT -alias ca1 -gencert -ext san=dns:ca2 |
$KT -alias ca2 -importcert
The following command creates the certificate e1 and stores it
in the file e1.cert, which is signed by ca2. As a result, e1
should contain ca, ca1, and ca2 in its certificate chain:
keytool-alias e1 -certreq | keytool-alias ca2 -gencert > e1.cert
-genkeypair
{-alias alias} {-keyalg keyalg} {-keysize keysize} {-sigalg sigalg}
[-dname dname] [-keypass keypass] {-startdate value} {-ext ext}*
{-validity valDays} {-storetype storetype} {-keystore keystore}
[-storepass storepass]
{-providerClass provider_class_name {-providerArg provider_arg}}
{-v} {-protected} {-Jjavaoption}
Generates a key pair (a public key and associated private key).
Wraps the public key into an X.509 v3 self-signed certificate,
which is stored as a single-element certificate chain. This
certificate chain and the private key are stored in a new
keystore entry identified by alias.
The keyalg value specifies the algorithm to be used to generate
the key pair, and the keysize value specifies the size of each
key to be generated. The sigalg value specifies the algorithm
that should be used to sign the self-signed certificate. This
algorithm must be compatible with the keyalg value.
The dname value specifies the X.500 Distinguished Name to be
associated with the value of alias, and is used as the issuer
and subject fields in the self-signed certificate. If no
distinguished name is provided at the command line, then the
user is prompted for one.
The value of keypass is a password used to protect the private
key of the generated key pair. If no password is provided, then
the user is prompted for it. If you press the Return key at the
prompt, then the key password is set to the same password as the
keystore password. The keypass value must be at least 6
characters.
The value of startdate specifies the issue time of the
certificate, also known as the "Not Before" value of the X.509
certificate's Validity field.
The option value can be set in one of these two forms:
([+-]nnn[ymdHMS])+
[yyyy/mm/dd] [HH:MM:SS]
With the first form, the issue time is shifted by the specified
value from the current time. The value is a concatenation of a
sequence of subvalues. Inside each subvalue, the plus sign (+)
means shift forward, and the minus sign (-) means shift
backward. The time to be shifted is nnn units of years, months,
days, hours, minutes, or seconds (denoted by a single character
of y, m, d, H, M, or S respectively). The exact value of the
issue time is calculated using the
java.util.GregorianCalendar.add(int field, int amount) method on
each subvalue, from left to right. For example, by specifying,
the issue time will be:
Calendar c = new GregorianCalendar();
c.add(Calendar.YEAR, -1);
c.add(Calendar.MONTH, 1);
c.add(Calendar.DATE, -1);
return c.getTime()
With the second form, the user sets the exact issue time in two
parts, year/month/day and hour:minute:second (using the local
time zone). The user can provide only one part, which means the
other part is the same as the current date (or time). The user
must provide the exact number of digits as shown in the format
definition (padding with 0 when shorter). When both the date and
time are provided, there is one (and only one) space character
between the two parts. The hour should always be provided in 24
hour format.
When the option is not provided, the start date is the current
time. The option can be provided at most once.
The value of valDays specifies the number of days (starting at
the date specified by -startdate, or the current date when
-startdate is not specified) for which the certificate should be
considered valid.
This command was named -genkey in earlier releases. The old name
is still supported in this release. The new name, -genkeypair,
is preferred going forward.
-genseckey
{-alias alias} {-keyalg keyalg} {-keysize keysize} [-keypass keypass]
{-storetype storetype} {-keystore keystore} [-storepass storepass]
{-providerClass provider_class_name {-providerArg provider_arg}} {-v}
{-protected} {-Jjavaoption}
Generates a secret key and stores it in a new
KeyStore.SecretKeyEntry identified by alias.
The value of keyalg specifies the algorithm to be used to
generate the secret key, and the value of keysize specifies the
size of the key to be generated. The keypass value is a password
that protects the secret key. If no password is provided, then
the user is prompted for it. If you press the Return key at the
prompt, then the key password is set to the same password that
is used for the keystore. The keypass value must be at least 6
characters.
-importcert
{-alias alias} {-file cert_file} [-keypass keypass] {-noprompt} {-trustcacerts}
{-storetype storetype} {-keystore keystore} [-storepass storepass]
{-providerName provider_name}
{-providerClass provider_class_name {-providerArg provider_arg}}
{-v} {-protected} {-Jjavaoption}
Reads the certificate or certificate chain (where the latter is
supplied in a PKCS#7 formatted reply or a sequence of X.509
certificates) from the file cert_file, and stores it in the
keystore entry identified by alias. If no file is specified,
then the certificate or certificate chain is read from stdin.
The keytool command can import X.509 v1, v2, and v3
certificates, and PKCS#7 formatted certificate chains consisting
of certificates of that type. The data to be imported must be
provided either in binary encoding format or in printable
encoding format (also known as Base64 encoding) as defined by
the Internet RFC 1421 standard. In the latter case, the encoding
must be bounded at the beginning by a string that starts with
-----BEGIN, and bounded at the end by a string that starts with
-----END.
You import a certificate for two reasons: To add it to the list
of trusted certificates, and to import a certificate reply
received from a certificate authority (CA) as the result of
submitting a Certificate Signing Request to that CA (see the
-certreq option in Commands).
Which type of import is intended is indicated by the value of
the -alias option. If the alias does not point to a key entry,
then the keytool command assumes you are adding a trusted
certificate entry. In this case, the alias should not already
exist in the keystore. If the alias does already exist, then the
keytool command outputs an error because there is already a
trusted certificate for that alias, and does not import the
certificate. If the alias points to a key entry, then the
keytool command assumes you are importing a certificate reply.
-importpassword
{-alias alias} [-keypass keypass] {-storetype storetype} {-keystore keystore}
[-storepass storepass]
{-providerClass provider_class_name {-providerArg provider_arg}}
{-v} {-protected} {-Jjavaoption}
Imports a passphrase and stores it in a new
KeyStore.SecretKeyEntry identified by alias. The passphrase may
be supplied via the standard input stream; otherwise the user is
prompted for it. keypass is a password used to protect the
imported passphrase. If no password is provided, the user is
prompted for it. If you press the Return key at the prompt, the
key password is set to the same password as that used for the
keystore. keypass must be at least 6 characters long.
-importkeystore
{-srcstoretype srcstoretype} {-deststoretype deststoretype}
[-srcstorepass srcstorepass] [-deststorepass deststorepass] {-srcprotected}
{-destprotected}
{-srcalias srcalias {-destalias destalias} [-srckeypass srckeypass]}
[-destkeypass destkeypass] {-noprompt}
{-srcProviderName src_provider_name} {-destProviderName dest_provider_name}
{-providerClass provider_class_name {-providerArg provider_arg}} {-v}
{-protected} {-Jjavaoption}
Imports a single entry or all entries from a source keystore to
a destination keystore.
When the -srcalias option is provided, the command imports the
single entry identified by the alias to the destination
keystore. If a destination alias is not provided with destalias,
then srcalias is used as the destination alias. If the source
entry is protected by a password, then srckeypass is used to
recover the entry. If srckeypass is not provided, then the
keytool command attempts to use srcstorepass to recover the
entry. If srcstorepass is either not provided or is incorrect,
then the user is prompted for a password. The destination entry
is protected with destkeypass. If destkeypass is not provided,
then the destination entry is protected with the source entry
password. For example, most third-party tools require storepass
and keypass in a PKCS #12 keystore to be the same. In order to
create a PKCS #12 keystore for these tools, always specify a
-destkeypass to be the same as -deststorepass.
If the -srcalias option is not provided, then all entries in the
source keystore are imported into the destination keystore. Each
destination entry is stored under the alias from the source
entry. If the source entry is protected by a password, then
srcstorepass is used to recover the entry. If srcstorepass is
either not provided or is incorrect, then the user is prompted
for a password. If a source keystore entry type is not supported
in the destination keystore, or if an error occurs while storing
an entry into the destination keystore, then the user is
prompted whether to skip the entry and continue or to quit. The
destination entry is protected with the source entry password.
If the destination alias already exists in the destination
keystore, then the user is prompted to either overwrite the
entry or to create a new entry under a different alias name.
If the -noprompt option is provided, then the user is not
prompted for a new destination alias. Existing entries are
overwritten with the destination alias name. Entries that cannot
be imported are skipped and a warning is displayed.
-printcertreq
{-file file}
Prints the content of a PKCS #10 format certificate request,
which can be generated by the keytool-certreq command. The
command reads the request from file. If there is no file, then
the request is read from the standard input.
-certreq
{-alias alias} {-dname dname} {-sigalg sigalg} {-file certreq_file}
[-keypass keypass] {-storetype storetype} {-keystore keystore}
[-storepass storepass] {-providerName provider_name}
{-providerClass provider_class_name {-providerArg provider_arg}}
{-v} {-protected} {-Jjavaoption}
Generates a Certificate Signing Request (CSR) using the PKCS #10
format.
A CSR is intended to be sent to a certificate authority (CA).
The CA authenticates the certificate requestor (usually off-
line) and will return a certificate or certificate chain, used
to replace the existing certificate chain (which initially
consists of a self-signed certificate) in the keystore.
The private key associated with alias is used to create the PKCS
#10 certificate request. To access the private key, the correct
password must be provided. If keypass is not provided at the
command line and is different from the password used to protect
the integrity of the keystore, then the user is prompted for it.
If dname is provided, then it is used as the subject in the CSR.
Otherwise, the X.500 Distinguished Name associated with alias is
used.
The sigalg value specifies the algorithm that should be used to
sign the CSR.
The CSR is stored in the file certreq_file. If no file is
specified, then the CSR is output to stdout.
Use the importcert command to import the response from the CA.
-exportcert
{-alias alias} {-file cert_file} {-storetype storetype} {-keystore keystore}
[-storepass storepass] {-providerName provider_name}
{-providerClass provider_class_name {-providerArg provider_arg}}
{-rfc} {-v} {-protected} {-Jjavaoption}
Reads from the keystore the certificate associated with alias
and stores it in the cert_file file. When no file is specified,
the certificate is output to stdout.
The certificate is by default output in binary encoding. If the
-rfc option is specified, then the output in the printable
encoding format defined by the Internet RFC 1421 Certificate
Encoding Standard.
If alias refers to a trusted certificate, then that certificate
is output. Otherwise, alias refers to a key entry with an
associated certificate chain. In that case, the first
certificate in the chain is returned. This certificate
authenticates the public key of the entity addressed by alias.
This command was named -export in earlier releases. The old name
is still supported in this release. The new name, -exportcert,
is preferred going forward.
-list
{-alias alias} {-storetype storetype} {-keystore keystore} [-storepass storepass]
{-providerName provider_name}
{-providerClass provider_class_name {-providerArg provider_arg}}
{-v | -rfc} {-protected} {-Jjavaoption}
Prints to stdout the contents of the keystore entry identified
by alias. If no alias is specified, then the contents of the
entire keystore are printed.
This command by default prints the SHA1 fingerprint of a
certificate. If the -v option is specified, then the certificate
is printed in human-readable format, with additional information
such as the owner, issuer, serial number, and any extensions. If
the -rfc option is specified, then the certificate contents are
printed using the printable encoding format, as defined by the
Internet RFC 1421 Certificate Encoding Standard.
You cannot specify both -v and -rfc.
-printcert
{-file cert_file | -sslserver host[:port]} {-jarfile JAR_file {-rfc} {-v}
{-Jjavaoption}
Reads the certificate from the file cert_file, the SSL server
located at host:port, or the signed JAR file JAR_file (with the
-jarfile option and prints its contents in a human-readable
format. When no port is specified, the standard HTTPS port 443
is assumed. Note that -sslserver and -file options cannot be
provided at the same time. Otherwise, an error is reported. If
neither option is specified, then the certificate is read from
stdin.
When-rfc is specified, the keytool command prints the
certificate in PEM mode as defined by the Internet RFC 1421
Certificate Encoding standard. See Internet RFC 1421 Certificate
Encoding Standard.
If the certificate is read from a file or stdin, then it might
be either binary encoded or in printable encoding format, as
defined by the RFC 1421 Certificate Encoding standard.
If the SSL server is behind a firewall, then the -J-
Dhttps.proxyHost=proxyhost and -J-Dhttps.proxyPort=proxyport
options can be specified on the command line for proxy
tunneling. See Java Secure Socket Extension (JSSE) Reference
Guide at
http://docs.oracle.com/javase/8/docs/technotes/guides/security/jsse/JSSERefGuide.html
Note: This option can be used independently of a keystore.
-printcrl
-file crl_ {-v}
Reads the Certificate Revocation List (CRL) from the file crl_.
A CRL is a list of digital certificates that were revoked by the
CA that issued them. The CA generates the crl_ file.
Note: This option can be used independently of a keystore.
-storepasswd
[-new new_storepass] {-storetype storetype} {-keystore keystore}
[-storepass storepass] {-providerName provider_name}
{-providerClass provider_class_name {-providerArg provider_arg}}
{-v} {-Jjavaoption}
Changes the password used to protect the integrity of the
keystore contents. The new password is new_storepass, which must
be at least 6 characters.
-keypasswd
{-alias alias} [-keypass old_keypass] [-new new_keypass] {-storetype storetype}
{-keystore keystore} [-storepass storepass] {-providerName provider_name}
{-providerClass provider_class_name {-providerArg provider_arg}} {-v}
{-Jjavaoption}
Changes the password under which the private/secret key
identified by alias is protected, from old_keypass to
new_keypass, which must be at least 6 characters.
If the -keypass option is not provided at the command line, and
the key password is different from the keystore password, then
the user is prompted for it.
If the -new option is not provided at the command line, then the
user is prompted for it
-delete
[-alias alias] {-storetype storetype} {-keystore keystore} [-storepass storepass]
{-providerName provider_name}
{-providerClass provider_class_name {-providerArg provider_arg}}
{-v} {-protected} {-Jjavaoption}
Deletes from the keystore the entry identified by alias. The
user is prompted for the alias, when no alias is provided at the
command line.
-changealias
{-alias alias} [-destalias destalias] [-keypass keypass] {-storetype storetype}
{-keystore keystore} [-storepass storepass] {-providerName provider_name}
{-providerClass provider_class_name {-providerArg provider_arg}} {-v}
{-protected} {-Jjavaoption}
Move an existing keystore entry from the specified alias to a
new alias, destalias. If no destination alias is provided, then
the command prompts for one. If the original entry is protected
with an entry password, then the password can be supplied with
the -keypass option. If no key password is provided, then the
storepass (if provided) is attempted first. If the attempt
fails, then the user is prompted for a password.
-help
Lists the basic commands and their options.
For more information about a specific command, enter the
following, where command_name is the name of the command:
keytool-command_name -help.
EXAMPLES
This example walks through the sequence of steps to create a keystore
for managing public/private key pair and certificates from trusted
entities.
GENERATE THE KEY PAIR
First, create a keystore and generate the key pair. You can use a
command such as the following typed as a single line:
keytool-genkeypair -dname "cn=Mark Jones, ou=Java, o=Oracle, c=US"
-alias business -keypass <new password for private key>
-keystore /working/mykeystore
-storepass <new password for keystore> -validity 180
The command creates the keystore named mykeystore in the working
directory (assuming it does not already exist), and assigns it the
password specified by <new password for keystore>. It generates a
public/private key pair for the entity whose distinguished name has a
common name of Mark Jones, organizational unit of Java, organization of
Oracle and two-letter country code of US. It uses the default DSA key
generation algorithm to create the keys; both are 1024 bits.
The command uses the default SHA1withDSA signature algorithm to create
a self-signed certificate that includes the public key and the
distinguished name information. The certificate is valid for 180 days,
and is associated with the private key in a keystore entry referred to
by the alias business. The private key is assigned the password
specified by <new password for private key>.
The command is significantly shorter when the option defaults are
accepted. In this case, no options are required, and the defaults are
used for unspecified options that have default values. You are prompted
for any required values. You could have the following:
keytool-genkeypair
In this case, a keystore entry with the alias mykey is created, with a
newly generated key pair and a certificate that is valid for 90 days.
This entry is placed in the keystore named .keystore in your home
directory. The keystore is created when it does not already exist. You
are prompted for the distinguished name information, the keystore
password, and the private key password.
The rest of the examples assume you executed the -genkeypair command
without options specified, and that you responded to the prompts with
values equal to those specified in the first -genkeypair command. For
example, a distinguished name of cn=Mark Jones, ou=Java, o=Oracle,
c=US).
REQUEST A SIGNED CERTIFICATE FROM A CA
Generating the key pair created a self-signed certificate. A
certificate is more likely to be trusted by others when it is signed by
a Certification Authority (CA). To get a CA signature, first generate a
Certificate Signing Request (CSR), as follows:
keytool-certreq -file MarkJ.csr
This creates a CSR for the entity identified by the default alias mykey
and puts the request in the file named MarkJ.csr. Submit this file to a
CA, such as VeriSign. The CA authenticates you, the requestor (usually
off-line), and returns a certificate, signed by them, authenticating
your public key. In some cases, the CA returns a chain of certificates,
each one authenticating the public key of the signer of the previous
certificate in the chain.
IMPORT A CERTIFICATE FOR THE CA
You now need to replace the self-signed certificate with a certificate
chain, where each certificate in the chain authenticates the public key
of the signer of the previous certificate in the chain, up to a root
CA.
Before you import the certificate reply from a CA, you need one or more
trusted certificates in your keystore or in the cacerts keystore file.
See -importcert in Commands.
· If the certificate reply is a certificate chain, then you need the
top certificate of the chain. The root CA certificate that
authenticates the public key of the CA.
· If the certificate reply is a single certificate, then you need a
certificate for the issuing CA (the one that signed it). If that
certificate is not self-signed, then you need a certificate for its
signer, and so on, up to a self-signed root CA certificate.
The cacerts keystore file ships with several VeriSign root CA
certificates, so you probably will not need to import a VeriSign
certificate as a trusted certificate in your keystore. But if you
request a signed certificate from a different CA, and a certificate
authenticating that CA's public key was not added to cacerts, then you
must import a certificate from the CA as a trusted certificate.
A certificate from a CA is usually either self-signed or signed by
another CA, in which case you need a certificate that authenticates
that CA's public key. Suppose company ABC, Inc., is a CA, and you
obtain a file named ABCCA.cer that is supposed to be a self-signed
certificate from ABC, that authenticates that CA's public key. Be
careful to ensure the certificate is valid before you import it as a
trusted certificate. View it first with the keytool-printcert command
or the keytool-importcert command without the -noprompt option, and
make sure that the displayed certificate fingerprints match the
expected ones. You can call the person who sent the certificate, and
compare the fingerprints that you see with the ones that they show or
that a secure public key repository shows. Only when the fingerprints
are equal is it guaranteed that the certificate was not replaced in
transit with somebody else's (for example, an attacker's) certificate.
If such an attack takes place, and you did not check the certificate
before you imported it, then you would be trusting anything the
attacker has signed.
If you trust that the certificate is valid, then you can add it to your
keystore with the following command:
keytool-importcert -alias abc -file ABCCA.cer
This command creates a trusted certificate entry in the keystore, with
the data from the file ABCCA.cer, and assigns the alias abc to the
entry.
IMPORT THE CERTIFICATE REPLY FROM THE CA
After you import a certificate that authenticates the public key of the
CA you submitted your certificate signing request to (or there is
already such a certificate in the cacerts file), you can import the
certificate reply and replace your self-signed certificate with a
certificate chain. This chain is the one returned by the CA in response
to your request (when the CA reply is a chain), or one constructed
(when the CA reply is a single certificate) using the certificate reply
and trusted certificates that are already available in the keystore
where you import the reply or in the cacerts keystore file.
For example, if you sent your certificate signing request to VeriSign,
then you can import the reply with the following, which assumes the
returned certificate is named VSMarkJ.cer:
keytool-importcert -trustcacerts -file VSMarkJ.cer
EXPORT A CERTIFICATE THAT AUTHENTICATES THE PUBLIC KEY
If you used the jarsigner command to sign a Java Archive (JAR) file,
then clients that want to use the file will want to authenticate your
signature. One way the clients can authenticate you is by first
importing your public key certificate into their keystore as a trusted
entry.
You can export the certificate and supply it to your clients. As an
example, you can copy your certificate to a file named MJ.cer with the
following command that assumes the entry has an alias of mykey:
keytool-exportcert -alias mykey -file MJ.cer
With the certificate and the signed JAR file, a client can use the
jarsigner command to authenticate your signature.
IMPORT KEYSTORE
The command importkeystore is used to import an entire keystore into
another keystore, which means all entries from the source keystore,
including keys and certificates, are all imported to the destination
keystore within a single command. You can use this command to import
entries from a different type of keystore. During the import, all new
entries in the destination keystore will have the same alias names and
protection passwords (for secret keys and private keys). If the keytool
command cannot recover the private keys or secret keys from the source
keystore, then it prompts you for a password. If it detects alias
duplication, then it asks you for a new alias, and you can specify a
new alias or simply allow the keytool command to overwrite the existing
one.
For example, to import entries from a typical JKS type keystore key.jks
into a PKCS #11 type hardware-based keystore, use the command:
keytool-importkeystore
-srckeystore key.jks -destkeystore NONE
-srcstoretype JKS -deststoretype PKCS11
-srcstorepass <src keystore password>
-deststorepass <destination keystore pwd>
The importkeystore command can also be used to import a single entry
from a source keystore to a destination keystore. In this case, besides
the options you see in the previous example, you need to specify the
alias you want to import. With the -srcalias option specified, you can
also specify the destination alias name in the command line, as well as
protection password for a secret/private key and the destination
protection password you want. The following command demonstrates this:
keytool-importkeystore
-srckeystore key.jks -destkeystore NONE
-srcstoretype JKS -deststoretype PKCS11
-srcstorepass <src keystore password>
-deststorepass <destination keystore pwd>
-srcalias myprivatekey -destalias myoldprivatekey
-srckeypass <source entry password>
-destkeypass <destination entry password>
-noprompt
GENERATE CERTIFICATES FOR AN SSL SERVER
The following are keytool commands to generate key pairs and
certificates for three entities: Root CA (root), Intermediate CA (ca),
and SSL server (server). Ensure that you store all the certificates in
the same keystore. In these examples, RSA is the recommended the key
algorithm.
keytool-genkeypair -keystore root.jks -alias root -ext bc:c
keytool-genkeypair -keystore ca.jks -alias ca -ext bc:c
keytool-genkeypair -keystore server.jks -alias server
keytool-keystore root.jks -alias root -exportcert -rfc > root.pem
keytool-storepass <storepass> -keystore ca.jks -certreq -alias ca |
keytool-storepass <storepass> -keystore root.jks
-gencert -alias root -ext BC=0 -rfc > ca.pem
keytool-keystore ca.jks -importcert -alias ca -file ca.pem
keytool-storepass <storepass> -keystore server.jks -certreq -alias server |
keytool-storepass <storepass> -keystore ca.jks -gencert -alias ca
-ext ku:c=dig,kE -rfc > server.pem
cat root.pem ca.pem server.pem |
keytool-keystore server.jks -importcert -alias server
TERMS
Keystore
A keystore is a storage facility for cryptographic keys and
certificates.
Keystore entries
Keystores can have different types of entries. The two most
applicable entry types for the keytool command include the
following:
Key entries: Each entry holds very sensitive cryptographic key
information, which is stored in a protected format to prevent
unauthorized access. Typically, a key stored in this type of
entry is a secret key, or a private key accompanied by the
certificate chain for the corresponding public key. See
Certificate Chains. The keytool command can handle both types of
entries, while the jarsigner tool only handles the latter type
of entry, that is private keys and their associated certificate
chains.
Trusted certificate entries: Each entry contains a single public
key certificate that belongs to another party. The entry is
called a trusted certificate because the keystore owner trusts
that the public key in the certificate belongs to the identity
identified by the subject (owner) of the certificate. The issuer
of the certificate vouches for this, by signing the certificate.
KeyStore aliases
All keystore entries (key and trusted certificate entries) are
accessed by way of unique aliases.
An alias is specified when you add an entity to the keystore
with the -genseckey command to generate a secret key, the
-genkeypair command to generate a key pair (public and private
key), or the -importcert command to add a certificate or
certificate chain to the list of trusted certificates.
Subsequent keytool commands must use this same alias to refer to
the entity.
For example, you can use the alias duke to generate a new
public/private key pair and wrap the public key into a self-
signed certificate with the following command. See Certificate
Chains.
keytool-genkeypair -alias duke -keypass dukekeypasswd
This example specifies an initial password of dukekeypasswd
required by subsequent commands to access the private key
associated with the alias duke. If you later want to change
Duke's private key password, use a command such as the
following:
keytool-keypasswd -alias duke -keypass dukekeypasswd -new newpass
This changes the password from dukekeypasswd to newpass. A
password should not be specified on a command line or in a
script unless it is for testing purposes, or you are on a secure
system. If you do not specify a required password option on a
command line, then you are prompted for it.
KeyStore implementation
The KeyStore class provided in the java.security package
supplies well-defined interfaces to access and modify the
information in a keystore. It is possible for there to be
multiple different concrete implementations, where each
implementation is that for a particular type of keystore.
Currently, two command-line tools (keytool and jarsigner) and a
GUI-based tool named Policy Tool make use of keystore
implementations. Because the KeyStore class is public, users can
write additional security applications that use it.
There is a built-in default implementation, provided by Oracle.
It implements the keystore as a file with a proprietary keystore
type (format) named JKS. It protects each private key with its
individual password, and also protects the integrity of the
entire keystore with a (possibly different) password.
Keystore implementations are provider-based. More specifically,
the application interfaces supplied by KeyStore are implemented
in terms of a Service Provider Interface (SPI). That is, there
is a corresponding abstract KeystoreSpi class, also in the
java.security package, which defines the Service Provider
Interface methods that providers must implement. The term
provider refers to a package or a set of packages that supply a
concrete implementation of a subset of services that can be
accessed by the Java Security API. To provide a keystore
implementation, clients must implement a provider and supply a
KeystoreSpi subclass implementation, as described in How to
Implement a Provider in the Java Cryptography Architecture at
http://docs.oracle.com/javase/8/docs/technotes/guides/security/crypto/HowToImplAProvider.html
Applications can choose different types of keystore
implementations from different providers, using the getInstance
factory method supplied in the KeyStore class. A keystore type
defines the storage and data format of the keystore information,
and the algorithms used to protect private/secret keys in the
keystore and the integrity of the keystore. Keystore
implementations of different types are not compatible.
The keytool command works on any file-based keystore
implementation. It treats the keystore location that is passed
to it at the command line as a file name and converts it to a
FileInputStream, from which it loads the keystore
information.)The jarsigner and policytool commands can read a
keystore from any location that can be specified with a URL.
For keytool and jarsigner, you can specify a keystore type at
the command line, with the -storetype option. For Policy Tool,
you can specify a keystore type with the Keystore menu.
If you do not explicitly specify a keystore type, then the tools
choose a keystore implementation based on the value of the
keystore.type property specified in the security properties
file. The security properties file is called java.security, and
resides in the security properties directory,
java.home\lib\security on Windows and java.home/lib/security on
Oracle Solaris, where java.home is the runtime environment
directory. The jre directory in the SDK or the top-level
directory of the Java Runtime Environment (JRE).
Each tool gets the keystore.type value and then examines all the
currently installed providers until it finds one that implements
a keystores of that type. It then uses the keystore
implementation from that provider.The KeyStore class defines a
static method named getDefaultType that lets applications and
applets retrieve the value of the keystore.type property. The
following line of code creates an instance of the default
keystore type as specified in the keystore.type property:
KeyStore keyStore = KeyStore.getInstance(KeyStore.getDefaultType());
The default keystore type is jks, which is the proprietary type
of the keystore implementation provided by Oracle. This is
specified by the following line in the security properties file:
keystore.type=jks
To have the tools utilize a keystore implementation other than
the default, you can change that line to specify a different
keystore type. For example, if you have a provider package that
supplies a keystore implementation for a keystore type called
pkcs12, then change the line to the following:
keystore.type=pkcs12
Note: Case does not matter in keystore type designations. For
example, JKS would be considered the same as jks.
Certificate
A certificate (or public-key certificate) is a digitally signed
statement from one entity (the issuer), saying that the public
key and some other information of another entity (the subject)
has some specific value. The following terms are related to
certificates:
Public Keys: These are numbers associated with a particular
entity, and are intended to be known to everyone who needs to
have trusted interactions with that entity. Public keys are used
to verify signatures.
Digitally Signed: If some data is digitally signed, then it is
stored with the identity of an entity and a signature that
proves that entity knows about the data. The data is rendered
unforgeable by signing with the entity's private key.
Identity: A known way of addressing an entity. In some systems,
the identity is the public key, and in others it can be anything
from an Oracle Solaris UID to an email address to an X.509
distinguished name.
Signature: A signature is computed over some data using the
private key of an entity. The signer, which in the case of a
certificate is also known as the issuer.
Private Keys: These are numbers, each of which is supposed to be
known only to the particular entity whose private key it is
(that is, it is supposed to be kept secret). Private and public
keys exist in pairs in all public key cryptography systems (also
referred to as public key crypto systems). In a typical public
key crypto system, such as DSA, a private key corresponds to
exactly one public key. Private keys are used to compute
signatures.
Entity: An entity is a person, organization, program, computer,
business, bank, or something else you are trusting to some
degree.
Public key cryptography requires access to users' public keys.
In a large-scale networked environment, it is impossible to
guarantee that prior relationships between communicating
entities were established or that a trusted repository exists
with all used public keys. Certificates were invented as a
solution to this public key distribution problem. Now a
Certification Authority (CA) can act as a trusted third party.
CAs are entities such as businesses that are trusted to sign
(issue) certificates for other entities. It is assumed that CAs
only create valid and reliable certificates because they are
bound by legal agreements. There are many public Certification
Authorities, such as VeriSign, Thawte, Entrust, and so on.
You can also run your own Certification Authority using products
such as Microsoft Certificate Server or the Entrust CA product
for your organization. With the keytool command, it is possible
to display, import, and export certificates. It is also possible
to generate self-signed certificates.
The keytool command currently handles X.509 certificates.
X.509 Certificates
The X.509 standard defines what information can go into a
certificate and describes how to write it down (the data
format). All the data in a certificate is encoded with two
related standards called ASN.1/DER. Abstract Syntax Notation 1
describes data. The Definite Encoding Rules describe a single
way to store and transfer that data.
All X.509 certificates have the following data, in addition to
the signature:
Version: This identifies which version of the X.509 standard
applies to this certificate, which affects what information can
be specified in it. Thus far, three versions are defined. The
keytool command can import and export v1, v2, and v3
certificates. It generates v3 certificates.
X.509 Version 1 has been available since 1988, is widely
deployed, and is the most generic.
X.509 Version 2 introduced the concept of subject and issuer
unique identifiers to handle the possibility of reuse of subject
or issuer names over time. Most certificate profile documents
strongly recommend that names not be reused and that
certificates should not make use of unique identifiers. Version
2 certificates are not widely used.
X.509 Version 3 is the most recent (1996) and supports the
notion of extensions where anyone can define an extension and
include it in the certificate. Some common extensions are:
KeyUsage (limits the use of the keys to particular purposes such
as signing-only) and AlternativeNames (allows other identities
to also be associated with this public key, for example. DNS
names, email addresses, IP addresses). Extensions can be marked
critical to indicate that the extension should be checked and
enforced or used. For example, if a certificate has the KeyUsage
extension marked critical and set to keyCertSign, then when this
certificate is presented during SSL communication, it should be
rejected because the certificate extension indicates that the
associated private key should only be used for signing
certificates and not for SSL use.
Serial number: The entity that created the certificate is
responsible for assigning it a serial number to distinguish it
from other certificates it issues. This information is used in
numerous ways. For example, when a certificate is revoked its
serial number is placed in a Certificate Revocation List (CRL).
Signature algorithm identifier: This identifies the algorithm
used by the CA to sign the certificate.
Issuer name: The X.500 Distinguished Name of the entity that
signed the certificate. See X.500 Distinguished Names. This is
typically a CA. Using this certificate implies trusting the
entity that signed this certificate. In some cases, such as root
or top-level CA certificates, the issuer signs its own
certificate.
Validity period: Each certificate is valid only for a limited
amount of time. This period is described by a start date and
time and an end date and time, and can be as short as a few
seconds or almost as long as a century. The validity period
chosen depends on a number of factors, such as the strength of
the private key used to sign the certificate, or the amount one
is willing to pay for a certificate. This is the expected period
that entities can rely on the public value, when the associated
private key has not been compromised.
Subject name: The name of the entity whose public key the
certificate identifies. This name uses the X.500 standard, so it
is intended to be unique across the Internet. This is the X.500
Distinguished Name (DN) of the entity. See X.500 Distinguished
Names. For example,
CN=Java Duke, OU=Java Software Division, O=Oracle Corporation, C=US
These refer to the subject's common name (CN), organizational
unit (OU), organization (O), and country (C).
Subject public key information: This is the public key of the
entity being named with an algorithm identifier that specifies
which public key crypto system this key belongs to and any
associated key parameters.
Certificate Chains
The keytool command can create and manage keystore key entries
that each contain a private key and an associated certificate
chain. The first certificate in the chain contains the public
key that corresponds to the private key.
When keys are first generated, the chain starts off containing a
single element, a self-signed certificate. See -genkeypair in
Commands. A self-signed certificate is one for which the issuer
(signer) is the same as the subject. The subject is the entity
whose public key is being authenticated by the certificate.
Whenever the -genkeypair command is called to generate a new
public/private key pair, it also wraps the public key into a
self-signed certificate.
Later, after a Certificate Signing Request (CSR) was generated
with the -certreq command and sent to a Certification Authority
(CA), the response from the CA is imported with -importcert, and
the self-signed certificate is replaced by a chain of
certificates. See the -certreq and -importcert options in
Commands. At the bottom of the chain is the certificate (reply)
issued by the CA authenticating the subject's public key. The
next certificate in the chain is one that authenticates the CA's
public key.
In many cases, this is a self-signed certificate, which is a
certificate from the CA authenticating its own public key, and
the last certificate in the chain. In other cases, the CA might
return a chain of certificates. In this case, the bottom
certificate in the chain is the same (a certificate signed by
the CA, authenticating the public key of the key entry), but the
second certificate in the chain is a certificate signed by a
different CA that authenticates the public key of the CA you
sent the CSR to. The next certificate in the chain is a
certificate that authenticates the second CA's key, and so on,
until a self-signed root certificate is reached. Each
certificate in the chain (after the first) authenticates the
public key of the signer of the previous certificate in the
chain.
Many CAs only return the issued certificate, with no supporting
chain, especially when there is a flat hierarchy (no
intermediates CAs). In this case, the certificate chain must be
established from trusted certificate information already stored
in the keystore.
A different reply format (defined by the PKCS #7 standard)
includes the supporting certificate chain in addition to the
issued certificate. Both reply formats can be handled by the
keytool command.
The top-level (root) CA certificate is self-signed. However, the
trust into the root's public key does not come from the root
certificate itself, but from other sources such as a newspaper.
This is because anybody could generate a self-signed certificate
with the distinguished name of, for example, the VeriSign root
CA. The root CA public key is widely known. The only reason it
is stored in a certificate is because this is the format
understood by most tools, so the certificate in this case is
only used as a vehicle to transport the root CA's public key.
Before you add the root CA certificate to your keystore, you
should view it with the -printcert option and compare the
displayed fingerprint with the well-known fingerprint obtained
from a newspaper, the root CA's Web page, and so on.
The cacerts Certificates File
A certificates file named cacerts resides in the security
properties directory, java.home\lib\security on Windows and
java.home/lib/security on Oracle Solaris, where java.home is the
runtime environment's directory, which would be the jre
directory in the SDK or the top-level directory of the JRE.
The cacerts file represents a system-wide keystore with CA
certificates. System administrators can configure and manage
that file with the keytool command by specifying jks as the
keystore type. The cacerts keystore file ships with a default
set of root CA certificates. You can list the default
certificates with the following command:
keytool-list -keystore java.home/lib/security/cacerts
The initial password of the cacerts keystore file is changeit.
System administrators should change that password and the
default access permission of that file upon installing the SDK.
Note: It is important to verify your cacerts file. Because you
trust the CAs in the cacerts file as entities for signing and
issuing certificates to other entities, you must manage the
cacerts file carefully. The cacerts file should contain only
certificates of the CAs you trust. It is your responsibility to
verify the trusted root CA certificates bundled in the cacerts
file and make your own trust decisions.
To remove an untrusted CA certificate from the cacerts file, use
the delete option of the keytool command. You can find the
cacerts file in the JRE installation directory. Contact your
system administrator if you do not have permission to edit this
file
Internet RFC 1421 Certificate Encoding Standard
Certificates are often stored using the printable encoding
format defined by the Internet RFC 1421 standard, instead of
their binary encoding. This certificate format, also known as
Base64 encoding, makes it easy to export certificates to other
applications by email or through some other mechanism.
Certificates read by the -importcert and -printcert commands can
be in either this format or binary encoded. The -exportcert
command by default outputs a certificate in binary encoding, but
will instead output a certificate in the printable encoding
format, when the -rfc option is specified.
The -list command by default prints the SHA1 fingerprint of a
certificate. If the -v option is specified, then the certificate
is printed in human-readable format. If the -rfc option is
specified, then the certificate is output in the printable
encoding format.
In its printable encoding format, the encoded certificate is
bounded at the beginning and end by the following text:
-----BEGIN CERTIFICATE-----
encoded certificate goes here.
-----END CERTIFICATE-----
X.500 Distinguished Names
X.500 Distinguished Names are used to identify entities, such as
those that are named by the subject and issuer (signer) fields
of X.509 certificates. The keytool command supports the
following subparts:
commonName: The common name of a person such as Susan Jones.
organizationUnit: The small organization (such as department or
division) name. For example, Purchasing.
localityName: The locality (city) name, for example, Palo Alto.
stateName: State or province name, for example, California.
country: Two-letter country code, for example, CH.
When you supply a distinguished name string as the value of a
-dname option, such as for the -genkeypair command, the string
must be in the following format:
CN=cName, OU=orgUnit, O=org, L=city, S=state, C=countryCode
All the italicized items represent actual values and the
previous keywords are abbreviations for the following:
CN=commonName
OU=organizationUnit
O=organizationName
L=localityName
S=stateName
C=country
A sample distinguished name string is:
CN=Mark Smith, OU=Java, O=Oracle, L=Cupertino, S=California, C=US
A sample command using such a string is:
keytool-genkeypair -dname "CN=Mark Smith, OU=Java, O=Oracle, L=Cupertino,
S=California, C=US" -alias mark
Case does not matter for the keyword abbreviations. For example,
CN, cn, and Cn are all treated the same.
Order matters; each subcomponent must appear in the designated
order. However, it is not necessary to have all the
subcomponents. You can use a subset, for example:
CN=Steve Meier, OU=Java, O=Oracle, C=US
If a distinguished name string value contains a comma, then the
comma must be escaped by a backslash (\) character when you
specify the string on a command line, as in:
cn=Peter Schuster, ou=Java\, Product Development, o=Oracle, c=US
It is never necessary to specify a distinguished name string on
a command line. When the distinguished name is needed for a
command, but not supplied on the command line, the user is
prompted for each of the subcomponents. In this case, a comma
does not need to be escaped by a backslash (\).
WARNINGS
IMPORTING TRUSTED CERTIFICATES WARNING
Important: Be sure to check a certificate very carefully before
importing it as a trusted certificate.
Windows Example:
View the certificate first with the -printcert command or the
-importcert command without the -noprompt option. Ensure that the
displayed certificate fingerprints match the expected ones. For
example, suppose sends or emails you a certificate that you put it in a
file named \tmp\cert. Before you consider adding the certificate to
your list of trusted certificates, you can execute a -printcert command
to view its fingerprints, as follows:
keytool-printcert -file \tmp\cert
Owner: CN=ll, OU=ll, O=ll, L=ll, S=ll, C=ll
Issuer: CN=ll, OU=ll, O=ll, L=ll, S=ll, C=ll
Serial Number: 59092b34
Valid from: Thu Sep 25 18:01:13 PDT 1997 until: Wed Dec 24 17:01:13 PST 1997
Certificate Fingerprints:
MD5: 11:81:AD:92:C8:E5:0E:A2:01:2E:D4:7A:D7:5F:07:6F
SHA1: 20:B6:17:FA:EF:E5:55:8A:D0:71:1F:E8:D6:9D:C0:37:13:0E:5E:FE
SHA256: 90:7B:70:0A:EA:DC:16:79:92:99:41:FF:8A:FE:EB:90:
17:75:E0:90:B2:24:4D:3A:2A:16:A6:E4:11:0F:67:A4
Oracle Solaris Example:
View the certificate first with the -printcert command or the
-importcert command without the -noprompt option. Ensure that the
displayed certificate fingerprints match the expected ones. For
example, suppose someone sends or emails you a certificate that you put
it in a file named /tmp/cert. Before you consider adding the
certificate to your list of trusted certificates, you can execute a
-printcert command to view its fingerprints, as follows:
keytool-printcert -file /tmp/cert
Owner: CN=ll, OU=ll, O=ll, L=ll, S=ll, C=ll
Issuer: CN=ll, OU=ll, O=ll, L=ll, S=ll, C=ll
Serial Number: 59092b34
Valid from: Thu Sep 25 18:01:13 PDT 1997 until: Wed Dec 24 17:01:13 PST 1997
Certificate Fingerprints:
MD5: 11:81:AD:92:C8:E5:0E:A2:01:2E:D4:7A:D7:5F:07:6F
SHA1: 20:B6:17:FA:EF:E5:55:8A:D0:71:1F:E8:D6:9D:C0:37:13:0E:5E:FE
SHA256: 90:7B:70:0A:EA:DC:16:79:92:99:41:FF:8A:FE:EB:90:
17:75:E0:90:B2:24:4D:3A:2A:16:A6:E4:11:0F:67:A4
Then call or otherwise contact the person who sent the certificate and
compare the fingerprints that you see with the ones that they show.
Only when the fingerprints are equal is it guaranteed that the
certificate was not replaced in transit with somebody else's
certificate such as an attacker's certificate. If such an attack took
place, and you did not check the certificate before you imported it,
then you would be trusting anything the attacker signed, for example, a
JAR file with malicious class files inside.
Note: It is not required that you execute a -printcert command before
importing a certificate. This is because before you add a certificate
to the list of trusted certificates in the keystore, the -importcert
command prints out the certificate information and prompts you to
verify it. You can then stop the import operation. However, you can do
this only when you call the -importcert command without the -noprompt
option. If the -noprompt option is specified, then there is no
interaction with the user.
PASSWORDS WARNING
Most commands that operate on a keystore require the store password.
Some commands require a private/secret key password. Passwords can be
specified on the command line in the -storepass and -keypass options.
However, a password should not be specified on a command line or in a
script unless it is for testing, or you are on a secure system. When
you do not specify a required password option on a command line, you
are prompted for it.
CERTIFICATE CONFORMANCE WARNING
The Internet standard RFC 5280 has defined a profile on conforming
X.509 certificates, which includes what values and value combinations
are valid for certificate fields and extensions. See the standard at
http://tools.ietf.org/rfc/rfc5280.txt
The keytool command does not enforce all of these rules so it can
generate certificates that do not conform to the standard. Certificates
that do not conform to the standard might be rejected by JRE or other
applications. Users should ensure that they provide the correct options
for -dname, -ext, and so on.
NOTES
IMPORT A NEW TRUSTED CERTIFICATE
Before you add the certificate to the keystore, the keytool command
verifies it by attempting to construct a chain of trust from that
certificate to a self-signed certificate (belonging to a root CA),
using trusted certificates that are already available in the keystore.
If the -trustcacerts option was specified, then additional certificates
are considered for the chain of trust, namely the certificates in a
file named cacerts.
If the keytool command fails to establish a trust path from the
certificate to be imported up to a self-signed certificate (either from
the keystore or the cacerts file), then the certificate information is
printed, and the user is prompted to verify it by comparing the
displayed certificate fingerprints with the fingerprints obtained from
some other (trusted) source of information, which might be the
certificate owner. Be very careful to ensure the certificate is valid
before importing it as a trusted certificate. See Importing Trusted
Certificates Warning. The user then has the option of stopping the
import operation. If the -noprompt option is specified, then there is
no interaction with the user.
IMPORT A CERTIFICATE REPLY
When you import a certificate reply, the certificate reply is validated
with trusted certificates from the keystore, and optionally, the
certificates configured in the cacerts keystore file when the
-trustcacerts option is specified. See The cacerts Certificates File.
The methods of determining whether the certificate reply is trusted are
as follows:
· If the reply is a single X.509 certificate, then the keytool command
attempts to establish a trust chain, starting at the certificate
reply and ending at a self-signed certificate (belonging to a root
CA). The certificate reply and the hierarchy of certificates is used
to authenticate the certificate reply from the new certificate chain
of aliases. If a trust chain cannot be established, then the
certificate reply is not imported. In this case, the keytool command
does not print the certificate and prompt the user to verify it,
because it is very difficult for a user to determine the authenticity
of the certificate reply.
· If the reply is a PKCS #7 formatted certificate chain or a sequence
of X.509 certificates, then the chain is ordered with the user
certificate first followed by zero or more CA certificates. If the
chain ends with a self-signed root CA certificate and the-
trustcacerts option was specified, the keytool command attempts to
match it with any of the trusted certificates in the keystore or the
cacerts keystore file. If the chain does not end with a self-signed
root CA certificate and the -trustcacerts option was specified, the
keytool command tries to find one from the trusted certificates in
the keystore or the cacerts keystore file and add it to the end of
the chain. If the certificate is not found and the -noprompt option
is not specified, the information of the last certificate in the
chain is printed, and the user is prompted to verify it.
If the public key in the certificate reply matches the user's public
key already stored with alias, then the old certificate chain is
replaced with the new certificate chain in the reply. The old chain can
only be replaced with a valid keypass, and so the password used to
protect the private key of the entry is supplied. If no password is
provided, and the private key password is different from the keystore
password, the user is prompted for it.
This command was named -import in earlier releases. This old name is
still supported in this release. The new name, -importcert, is
preferred going forward.
SEE ALSO
· jar(1)
· jarsigner(1)
· Trail: Security Features in Java SE at
http://docs.oracle.com/javase/tutorial/security/index.html
JDK 8 03 March 2015 keytool(1)
