Abstract class for X.509 v1 certificates. This provides a standard way to access all the version 1 attributes of an X.509 certificate. Attributes that are specific to X.509 v2 or v3 are not available through this interface. Future API evolution will provide full access to complete X.509 v3 attributes.
The basic X.509 format was defined by ISO/IEC and ANSI X9 and is described below in ASN.1:
Certificate ::= SEQUENCE { tbsCertificate TBSCertificate, signatureAlgorithm AlgorithmIdentifier, signature BIT STRING }
These certificates are widely used to support authentication and other functionality in Internet security systems. Common applications include Privacy Enhanced Mail (PEM), Transport Layer Security (SSL), code signing for trusted software distribution, and Secure Electronic Transactions (SET).
These certificates are managed and vouched for by Certificate Authorities (CAs). CAs are services which create certificates by placing data in the X.509 standard format and then digitally signing that data. CAs act as trusted third parties, making introductions between principals who have no direct knowledge of each other. CA certificates are either signed by themselves, or by some other CA such as a "root" CA.
The ASN.1 definition of tbsCertificate
is:
TBSCertificate ::= SEQUENCE { version [0] EXPLICIT Version DEFAULT v1, serialNumber CertificateSerialNumber, signature AlgorithmIdentifier, issuer Name, validity Validity, subject Name, subjectPublicKeyInfo SubjectPublicKeyInfo, }
Here is sample code to instantiate an X.509 certificate:
InputStream inStream = new FileInputStream("fileName-of-cert"); X509Certificate cert = X509Certificate.getInstance(inStream); inStream.close();OR
byte[] certData = <certificate read from a file, say> X509Certificate cert = X509Certificate.getInstance(certData);
In either case, the code that instantiates an X.509 certificate
consults the value of the cert.provider.x509v1
security property
to locate the actual implementation or instantiates a default implementation.
The cert.provider.x509v1
property is set to a default
implementation for X.509 such as:
cert.provider.x509v1=com.sun.security.cert.internal.x509.X509V1CertImpl
The value of this cert.provider.x509v1
property has to be
changed to instantiate another implementation. If this security
property is not set, a default implementation will be used.
Currently, due to possible security restrictions on access to
Security properties, this value is looked up and cached at class
initialization time and will fallback on a default implementation if
the Security property is not accessible.
Note: The classes in the package javax.security.cert
exist for compatibility with earlier versions of the
Java Secure Sockets Extension (JSSE). New applications should instead
use the standard Java SE certificate classes located in
java.security.cert
.
Public Constructor Summary
X509Certificate()
Creates a new
X509Certificate . |
Public Method Summary
abstract void |
checkValidity()
Checks whether the certificate is currently valid.
|
abstract void |
checkValidity(Date date)
Checks that the specified date is within the certificate's
validity period.
|
final static X509Certificate |
getInstance(byte[] certData)
Creates a new
X509Certificate and initializes it from the
specified byte array. |
final static X509Certificate |
getInstance(InputStream inStream)
Instantiates an X509Certificate object, and initializes it with
the data read from the input stream
inStream . |
abstract Principal |
getIssuerDN()
Gets the
issuer (issuer distinguished name) value from
the certificate. |
abstract Date |
getNotAfter()
Gets the
notAfter date from the validity period of
the certificate. |
abstract Date |
getNotBefore()
Gets the
notBefore date from the validity period of
the certificate. |
abstract BigInteger |
getSerialNumber()
Gets the
serialNumber value from the certificate. |
abstract String |
getSigAlgName()
Gets the signature algorithm name for the certificate
signature algorithm.
|
abstract String |
getSigAlgOID()
Gets the signature algorithm OID string from the certificate.
|
abstract byte[] |
getSigAlgParams()
Gets the DER-encoded signature algorithm parameters from this
certificate's signature algorithm.
|
abstract Principal |
getSubjectDN()
Gets the
subject (subject distinguished name) value
from the certificate. |
abstract int |
getVersion()
Gets the
version (version number) value from the
certificate. |
Inherited Method Summary
Public Constructors
public X509Certificate ()
Creates a new X509Certificate
.
Public Methods
public abstract void checkValidity ()
Checks whether the certificate is currently valid.
The validity period consists of two date/time values: the first and last dates (and times) on which the certificate is valid. It is defined in ASN.1 as:
validity Validity Validity ::= SEQUENCE { notBefore CertificateValidityDate, notAfter CertificateValidityDate } CertificateValidityDate ::= CHOICE { utcTime UTCTime, generalTime GeneralizedTime }
Throws
CertificateExpiredException | if the certificate has expired. |
---|---|
CertificateNotYetValidException | if the certificate is not yet valid. |
public abstract void checkValidity (Date date)
Checks that the specified date is within the certificate's validity period. In other words, this determines whether the certificate would be valid at the specified date/time.
Parameters
date | the Date to check against to see if this certificate is valid at that date/time. |
---|
Throws
CertificateExpiredException | if the certificate has expired
with respect to the date supplied. |
---|---|
CertificateNotYetValidException | if the certificate is not
yet valid with respect to the date supplied. |
See Also
public static final X509Certificate getInstance (byte[] certData)
Creates a new X509Certificate
and initializes it from the
specified byte array.
Parameters
certData | byte array containing data to initialize the certificate. |
---|
Returns
- the certificate initialized from the specified byte array
Throws
CertificateException | if the certificate cannot be created or initialized. |
---|
public static final X509Certificate getInstance (InputStream inStream)
Instantiates an X509Certificate object, and initializes it with
the data read from the input stream inStream
.
The implementation (X509Certificate is an abstract class) is
provided by the class specified as the value of the
cert.provider.x509v1
security property.
Note: Only one DER-encoded certificate is expected to be in the input stream. Also, all X509Certificate subclasses must provide a constructor of the form:
public <subClass>(InputStream inStream) ...
Parameters
inStream | an input stream with the data to be read to initialize the certificate. |
---|
Returns
- an X509Certificate object initialized with the data from the input stream.
Throws
CertificateException | if a class initialization or certificate parsing error occurs. |
---|
public abstract Principal getIssuerDN ()
Gets the issuer
(issuer distinguished name) value from
the certificate. The issuer name identifies the entity that signed (and
issued) the certificate.
The issuer name field contains an X.500 distinguished name (DN). The ASN.1 definition for this is:
issuer Name Name ::= CHOICE { RDNSequence } RDNSequence ::= SEQUENCE OF RelativeDistinguishedName RelativeDistinguishedName ::= SET OF AttributeValueAssertion AttributeValueAssertion ::= SEQUENCE { AttributeType, AttributeValue } AttributeType ::= OBJECT IDENTIFIER AttributeValue ::= ANYThe
Name
describes a hierarchical name composed of
attributes, such as country name, and corresponding values, such as US.
The type of the AttributeValue
component is determined by
the AttributeType
; in general it will be a
directoryString
. A directoryString
is usually
one of PrintableString
,
TeletexString
or UniversalString
.Returns
- a Principal whose name is the issuer distinguished name.
public abstract Date getNotAfter ()
Gets the notAfter
date from the validity period of
the certificate. See getNotBefore
for relevant ASN.1 definitions.
Returns
- the end date of the validity period.
See Also
public abstract Date getNotBefore ()
Gets the notBefore
date from the validity period of
the certificate.
The relevant ASN.1 definitions are:
validity Validity Validity ::= SEQUENCE { notBefore CertificateValidityDate, notAfter CertificateValidityDate } CertificateValidityDate ::= CHOICE { utcTime UTCTime, generalTime GeneralizedTime }
Returns
- the start date of the validity period.
See Also
public abstract BigInteger getSerialNumber ()
Gets the serialNumber
value from the certificate.
The serial number is an integer assigned by the certification
authority to each certificate. It must be unique for each
certificate issued by a given CA (i.e., the issuer name and
serial number identify a unique certificate).
The ASN.1 definition for this is:
serialNumber CertificateSerialNumber CertificateSerialNumber ::= INTEGER
Returns
- the serial number.
public abstract String getSigAlgName ()
Gets the signature algorithm name for the certificate signature algorithm. An example is the string "SHA-1/DSA". The ASN.1 definition for this is:
signatureAlgorithm AlgorithmIdentifier AlgorithmIdentifier ::= SEQUENCE { algorithm OBJECT IDENTIFIER, parameters ANY DEFINED BY algorithm OPTIONAL } -- contains a value of the type -- registered for use with the -- algorithm object identifier value
The algorithm name is determined from the algorithm
OID string.
Returns
- the signature algorithm name.
public abstract String getSigAlgOID ()
Gets the signature algorithm OID string from the certificate. An OID is represented by a set of positive whole numbers separated by periods. For example, the string "1.2.840.10040.4.3" identifies the SHA-1 with DSA signature algorithm, as per the PKIX part I.
See getSigAlgName
for
relevant ASN.1 definitions.
Returns
- the signature algorithm OID string.
public abstract byte[] getSigAlgParams ()
Gets the DER-encoded signature algorithm parameters from this certificate's signature algorithm. In most cases, the signature algorithm parameters are null; the parameters are usually supplied with the certificate's public key.
See getSigAlgName
for
relevant ASN.1 definitions.
Returns
- the DER-encoded signature algorithm parameters, or null if no parameters are present.
public abstract Principal getSubjectDN ()
Gets the subject
(subject distinguished name) value
from the certificate.
The ASN.1 definition for this is:
subject Name
See getIssuerDN
for Name
and other relevant definitions.
Returns
- a Principal whose name is the subject name.
See Also
public abstract int getVersion ()
Gets the version
(version number) value from the
certificate. The ASN.1 definition for this is:
version [0] EXPLICIT Version DEFAULT v1 Version ::= INTEGER { v1(0), v2(1), v3(2) }
Returns
- the version number from the ASN.1 encoding, i.e. 0, 1 or 2.