Package com.itextpdf.signatures

Class CertificateUtil

java.lang.Object
com.itextpdf.signatures.CertificateUtil
public class CertificateUtil extends Object
This class contains a series of static methods that allow you to retrieve information from a Certificate.

  • Constructor Details

    • CertificateUtil

      public CertificateUtil()

  • Method Details

    • getCRL

      public static CRL getCRL (X509Certificate certificate) throws CertificateException, CRLException, IOException
      Gets a CRL from an X509 certificate.
      Parameters:
      certificate - the X509Certificate to extract the CRL from
      Returns:
      CRL or null if there's no CRL available
      Throws:
      IOException - thrown when the URL couldn't be opened properly.
      CertificateException - thrown if there's no X509 implementation in the provider.
      CRLException - thrown when encountering errors when parsing the CRL.

    • getCRLURL

      public static String getCRLURL (X509Certificate certificate)
      Gets the URL of the Certificate Revocation List for a Certificate
      Parameters:
      certificate - the Certificate
      Returns:
      the String where you can check if the certificate was revoked

    • getDistributionPointByName

      public static IDistributionPoint getDistributionPointByName (X509Certificate certificate, IDistributionPointName issuingDistributionPointName)
      Gets the Distribution Point from the certificate by name specified in the Issuing Distribution Point from the Certificate Revocation List for a Certificate.
      Parameters:
      certificate - the certificate to retrieve Distribution Points
      issuingDistributionPointName - distributionPointName retrieved from the IDP of the CRL
      Returns:
      distribution point withthe same name as specified in the IDP.

    • getCRL

      public static CRL getCRL (String url) throws IOException, CertificateException, CRLException
      Gets the CRL object using a CRL URL.
      Parameters:
      url - the URL where the CRL is located
      Returns:
      CRL object
      Throws:
      IOException - thrown when the URL couldn't be opened properly.
      CertificateException - thrown if there's no X509 implementation in the provider.
      CRLException - thrown when encountering errors when parsing the CRL.

    • parseCrlFromStream

      public static CRL parseCrlFromStream (InputStream input) throws CertificateException, CRLException
      Parses a CRL from an InputStream.
      Parameters:
      input - the InputStream holding the unparsed CRL
      Returns:
      the parsed CRL object.
      Throws:
      CertificateException - thrown if there's no X509 implementation in the provider.
      CRLException - thrown when encountering errors when parsing the CRL.

    • getIssuerCertURL

      public static String getIssuerCertURL (CRL crl)
      Retrieves the URL for the issuer certificate for the given CRL.
      Parameters:
      crl - the CRL response
      Returns:
      the URL or null.

    • getOCSPURL

      public static String getOCSPURL (X509Certificate certificate)
      Retrieves the OCSP URL from the given certificate.
      Parameters:
      certificate - the certificate
      Returns:
      the URL or null

    • getIssuerCertURL

      public static String getIssuerCertURL (X509Certificate certificate)
      Retrieves the URL for the issuer lists certificates for the given certificate.
      Parameters:
      certificate - the certificate
      Returns:
      the URL or null.

    • getTSAURL

      public static String getTSAURL (X509Certificate certificate)
      Gets the URL of the TSA if it's available on the certificate
      Parameters:
      certificate - a certificate
      Returns:
      a TSA URL

    • generateCertificate

      public static Certificate generateCertificate (InputStream data) throws CertificateException
      Generates a certificate object and initializes it with the data read from the input stream inStream.
      Parameters:
      data - the input stream with the certificates.
      Returns:
      a certificate object initialized with the data from the input stream.
      Throws:
      CertificateException - on parsing errors.

    • retrieveRevocationInfoFromSignedData

      public static void retrieveRevocationInfoFromSignedData (IASN1TaggedObject taggedObj, Collection<CRL> crls, Collection<IBasicOCSPResponse> ocsps, Collection<IASN1Sequence> otherRevocationInfoFormats) throws IOException, CertificateException
      Try to retrieve CRL and OCSP responses from the signed data crls field.
      Parameters:
      taggedObj - signed data crls field as IASN1TaggedObject.
      crls - collection to store retrieved CRL responses.
      ocsps - collection of IBasicOCSPResponse wrappers to store retrieved OCSP responses.
      otherRevocationInfoFormats - collection of revocation info other than OCSP and CRL responses, e.g. SCVP Request and Response, stored as IASN1Sequence.
      Throws:
      IOException - if some I/O error occurred.
      CertificateException - if CertificateFactory instance wasn't created.

    • createRevocationInfoChoices

      public static IDERSet createRevocationInfoChoices (Collection<CRL> crls, Collection<IBasicOCSPResponse> ocsps, Collection<IASN1Sequence> otherRevocationInfoFormats) throws CRLException, IOException
      Creates the revocation info (crls field) for SignedData structure: RevocationInfoChoices ::= SET OF RevocationInfoChoice RevocationInfoChoice ::= CHOICE { crl CertificateList, other [1] IMPLICIT OtherRevocationInfoFormat } OtherRevocationInfoFormat ::= SEQUENCE { otherRevInfoFormat OBJECT IDENTIFIER, otherRevInfo ANY DEFINED BY otherRevInfoFormat } CertificateList ::= SEQUENCE { tbsCertList TBSCertList, signatureAlgorithm AlgorithmIdentifier, signatureValue BIT STRING }
      Parameters:
      crls - collection of CRL revocation status information.
      ocsps - collection of OCSP revocation status information.
      otherRevocationInfoFormats - collection of revocation info other than OCSP and CRL responses, e.g. SCVP Request and Response, stored as IASN1Sequence.
      Returns:
      crls [1] RevocationInfoChoices field of SignedData structure. Null if SignedData has no revocation data.
      Throws:
      CRLException - if an encoding error occurs.
      IOException - if an I/O error occurs.
      See Also:

    • checkIfIssuersMatch

      public static boolean checkIfIssuersMatch (ICertificateID certID, X509Certificate issuerCert) throws AbstractOperatorCreationException, AbstractOCSPException, CertificateEncodingException, IOException
      Checks if the issuer of the provided certID (specified in the OCSP response) and provided issuer of the certificate in question matches, i.e. checks that issuerNameHash and issuerKeyHash fields of the certID is the hash of the issuer's name and public key.

      SingleResp contains the basic information of the status of the certificate identified by the certID. The issuer name and serial number identify a unique certificate, so if serial numbers of the certificate in question and certID serial number are equals and issuers match, then SingleResp contains the information about the status of the certificate in question.

      Parameters:
      certID - certID specified in the OCSP response
      issuerCert - the issuer of the certificate in question
      Returns:
      true if the issuers are the same, false otherwise.
      Throws:
      AbstractOperatorCreationException - in case some digest calculator creation error.
      AbstractOCSPException - in case some digest calculator creation error.
      CertificateEncodingException - if an encoding error occurs.
      IOException - if input-output exception occurs.

    • getExtensionValueByOid

      public static byte[] getExtensionValueByOid (X509Certificate certificate, String id)
      Retrieves certificate extension value by its OID.
      Parameters:
      certificate - to get extension from
      id - extension OID to retrieve
      Returns:
      encoded extension value.

    • isSignatureValid

      public static boolean isSignatureValid (IBasicOCSPResp ocspResp, Certificate responderCert)
      Checks if an OCSP response is genuine.
      Parameters:
      ocspResp - IBasicOCSPResp the OCSP response wrapper
      responderCert - the responder certificate
      Returns:
      true if the OCSP response verifies against the responder certificate.

    • isSelfSigned

      public static boolean isSelfSigned (X509Certificate certificate)
      Checks if the certificate is self-signed.
      Parameters:
      certificate - a certificate to check
      Returns:
      true if the certificate is self-signed.

    • getExtensionValue

      public static IASN1Primitive getExtensionValue (X509Certificate certificate, String oid) throws IOException
      Gets certificate extension value.
      Parameters:
      certificate - the certificate from which we need the ExtensionValue
      oid - the Object Identifier value for the extension
      Returns:
      the extension value as an IASN1Primitive object.
      Throws:
      IOException - on processing exception.

    • getExtensionValue

      public static IASN1Primitive getExtensionValue (CRL crl, String oid) throws IOException
      Gets CRL extension value.
      Parameters:
      crl - the CRL from which we need the ExtensionValue
      oid - the Object Identifier value for the extension
      Returns:
      the extension value as an IASN1Primitive object.
      Throws:
      IOException - on processing exception.