Class PdfPKCS7

java.lang.Object
com.itextpdf.signatures.PdfPKCS7

public class PdfPKCS7 extends Object
This class does all the processing related to signing and verifying a PKCS#7 / CMS signature.
  • Field Details

    • BOUNCY_CASTLE_FACTORY

      private static final IBouncyCastleFactory BOUNCY_CASTLE_FACTORY
    • signaturePolicyIdentifier

      private ISignaturePolicyIdentifier signaturePolicyIdentifier
    • provider

      private final String provider
      The encryption provider, e.g. "BC" if you use BouncyCastle.
    • signName

      private String signName
      Holds value of property signName.
    • reason

      private String reason
      Holds value of property reason.
    • location

      private String location
      Holds value of property location.
    • signDate

      private Calendar signDate
      Holds value of property signDate.
    • signedDataRevocationInfo

      private final Collection<IASN1Sequence> signedDataRevocationInfo
      Collection to store revocation info other than OCSP and CRL responses, e.g. SCVP Request and Response.
    • version

      private int version
      Version of the PKCS#7 object
    • signerversion

      private int signerversion
      Version of the PKCS#7 "SignerInfo" object.
    • digestAlgorithmOid

      private final String digestAlgorithmOid
      The ID of the digest algorithm, e.g. "2.16.840.1.101.3.4.2.1".
    • messageDigest

      private MessageDigest messageDigest
      The object that will create the digest
    • digestalgos

      private Set<String> digestalgos
      The digest algorithms
    • digestAttr

      private byte[] digestAttr
      The digest attributes
    • filterSubtype

      private PdfName filterSubtype
    • signatureMechanismOid

      private String signatureMechanismOid
      The signature algorithm.
    • signatureMechanismParameters

      private IASN1Encodable signatureMechanismParameters
    • interfaceDigest

      private IExternalDigest interfaceDigest
    • externalSignatureValue

      private byte[] externalSignatureValue
      The signature value or signed digest, if created outside this class
    • externalEncapMessageContent

      private byte[] externalEncapMessageContent
      Externally specified encapsulated message content.
    • sig

      private Signature sig
      Class from the Java SDK that provides the functionality of a digital signature algorithm.
    • signatureValue

      private byte[] signatureValue
      The raw signature value as calculated by this class (or extracted from an existing PDF)
    • encapMessageContent

      private byte[] encapMessageContent
      The content to which the signature applies, if encapsulated in the PKCS #7 payload.
    • sigAttr

      private byte[] sigAttr
      Signature attributes
    • sigAttrDer

      private byte[] sigAttrDer
      Signature attributes (maybe not necessary, but we use it as fallback)
    • encContDigest

      private MessageDigest encContDigest
      encrypted digest
    • verified

      private boolean verified
      Indicates if a signature has already been verified
    • verifyResult

      private boolean verifyResult
      The result of the verification
    • certs

      private final Collection<Certificate> certs
      All the X.509 certificates in no particular order.
    • timestampCerts

      private Collection<Certificate> timestampCerts
    • signCerts

      All the X.509 certificates used for the main signature.
    • signCert

      private X509Certificate signCert
      The X.509 certificate that is used to sign the digest.
    • crls

      private Collection<CRL> crls
    • signedDataCrls

      private final Collection<CRL> signedDataCrls
    • basicResp

      BouncyCastle IBasicOCSPResponse
    • signedDataOcsps

      private final Collection<IBasicOCSPResponse> signedDataOcsps
    • isTsp

      private boolean isTsp
      True if there's a PAdES LTV time stamp.
    • isCades

      private boolean isCades
      True if it's a CAdES signature type.
    • timestampSignatureContainer

      private PdfPKCS7 timestampSignatureContainer
      Inner timestamp signature container.
    • timeStampTokenInfo

      private ITSTInfo timeStampTokenInfo
      BouncyCastle TSTInfo.
  • Constructor Details

    • PdfPKCS7

      public PdfPKCS7(PrivateKey privKey, Certificate[] certChain, String hashAlgorithm, String provider, IExternalDigest interfaceDigest, boolean hasEncapContent) throws InvalidKeyException, NoSuchProviderException, NoSuchAlgorithmException
      Assembles all the elements needed to create a signature, except for the data.
      Parameters:
      privKey - the private key
      certChain - the certificate chain
      hashAlgorithm - the hash algorithm
      provider - the provider or null for the default provider
      interfaceDigest - the interface digest
      hasEncapContent - true if the sub-filter is adbe.pkcs7.sha1
      Throws:
      InvalidKeyException - on error
      NoSuchProviderException - on error
      NoSuchAlgorithmException - on error
    • PdfPKCS7

      public PdfPKCS7(PrivateKey privKey, Certificate[] certChain, String hashAlgorithm, String provider, boolean hasEncapContent) throws InvalidKeyException, NoSuchProviderException, NoSuchAlgorithmException
      Assembles all the elements needed to create a signature, except for the data.
      Parameters:
      privKey - the private key
      certChain - the certificate chain
      hashAlgorithm - the hash algorithm
      provider - the provider or null for the default provider
      hasEncapContent - true if the sub-filter is adbe.pkcs7.sha1
      Throws:
      InvalidKeyException - on error
      NoSuchProviderException - on error
      NoSuchAlgorithmException - on error
    • PdfPKCS7

      public PdfPKCS7(byte[] contentsKey, byte[] certsKey, String provider)
      Use this constructor if you want to verify a signature using the sub-filter adbe.x509.rsa_sha1.
      Parameters:
      contentsKey - the /Contents key
      certsKey - the /Cert key
      provider - the provider or null for the default provider
    • PdfPKCS7

      public PdfPKCS7(byte[] contentsKey, PdfName filterSubtype, String provider)
      Use this constructor if you want to verify a signature.
      Parameters:
      contentsKey - the /Contents key
      filterSubtype - the filtersubtype
      provider - the provider or null for the default provider
  • Method Details

    • setSignaturePolicy

      public void setSignaturePolicy(SignaturePolicyInfo signaturePolicy)
      Set signature policy identifier to be used during signature creation.
      Parameters:
      signaturePolicy - SignaturePolicyInfo to be used during signature creation
    • setSignaturePolicy

      public void setSignaturePolicy(ISignaturePolicyIdentifier signaturePolicy)
      Set signature policy identifier to be used during signature creation.
      Parameters:
      signaturePolicy - ISignaturePolicyIdentifier to be used during signature creation
    • getSignName

      public String getSignName()
      Getter for property sigName.
      Returns:
      Value of property sigName.
    • setSignName

      public void setSignName(String signName)
      Setter for property sigName.
      Parameters:
      signName - New value of property sigName.
    • getReason

      public String getReason()
      Getter for property reason.
      Returns:
      Value of property reason.
    • setReason

      public void setReason(String reason)
      Setter for property reason.
      Parameters:
      reason - New value of property reason.
    • getLocation

      public String getLocation()
      Getter for property location.
      Returns:
      Value of property location.
    • setLocation

      public void setLocation(String location)
      Setter for property location.
      Parameters:
      location - New value of property location.
    • getSignDate

      public Calendar getSignDate()
      Getter for property signDate.
      Returns:
      Value of property signDate.
    • setSignDate

      public void setSignDate(Calendar signDate)
      Setter for property signDate.
      Parameters:
      signDate - New value of property signDate.
    • getVersion

      public int getVersion()
      Get the version of the PKCS#7 object.
      Returns:
      the version of the PKCS#7 object.
    • getSigningInfoVersion

      public int getSigningInfoVersion()
      Get the version of the PKCS#7 "SignerInfo" object.
      Returns:
      the version of the PKCS#7 "SignerInfo" object.
    • getDigestAlgorithmOid

      public String getDigestAlgorithmOid()
      Getter for the ID of the digest algorithm, e.g. "2.16.840.1.101.3.4.2.1". See ISO-32000-1, section 12.8.3.3 PKCS#7 Signatures as used in ISO 32000
      Returns:
      the ID of the digest algorithm
    • getDigestAlgorithmName

      public String getDigestAlgorithmName()
      Returns the name of the digest algorithm, e.g. "SHA256".
      Returns:
      the digest algorithm name, e.g. "SHA256"
    • getSignatureMechanismOid

      public String getSignatureMechanismOid()
      Getter for the signature algorithm OID. See ISO-32000-1, section 12.8.3.3 PKCS#7 Signatures as used in ISO 32000
      Returns:
      the signature algorithm OID
    • getSignatureMechanismName

      public String getSignatureMechanismName()
      Get the signature mechanism identifier, including both the digest function and the signature algorithm, e.g. "SHA1withRSA". See ISO-32000-1, section 12.8.3.3 PKCS#7 Signatures as used in ISO 32000
      Returns:
      the algorithm used to calculate the signature
    • getSignatureAlgorithmName

      public String getSignatureAlgorithmName()
      Returns the name of the signature algorithm only (disregarding the digest function, if any).
      Returns:
      the name of an encryption algorithm
    • setExternalSignatureValue

      public void setExternalSignatureValue(byte[] signatureValue, byte[] signedMessageContent, String signatureAlgorithm)
      Sets the signature to an externally calculated value.
      Parameters:
      signatureValue - the signature value
      signedMessageContent - the extra data that goes into the data tag in PKCS#7
      signatureAlgorithm - the signature algorithm. It must be null if the signatureValue is also null. If the signatureValue is not null, possible values include "RSA", "DSA", "ECDSA", "Ed25519" and "Ed448".
    • setExternalSignatureValue

      public void setExternalSignatureValue(byte[] signatureValue, byte[] signedMessageContent, String signatureAlgorithm, ISignatureMechanismParams signatureMechanismParams)
      Sets the signature to an externally calculated value.
      Parameters:
      signatureValue - the signature value
      signedMessageContent - the extra data that goes into the data tag in PKCS#7
      signatureAlgorithm - the signature algorithm. It must be null if the signatureValue is also null. If the signatureValue is not null, possible values include "RSA", "RSASSA-PSS", "DSA", "ECDSA", "Ed25519" and "Ed448".
      signatureMechanismParams - parameters for the signature mechanism, if required
    • initSignature

      Throws:
      NoSuchAlgorithmException
      NoSuchProviderException
      InvalidKeyException
    • initSignature

      Throws:
      NoSuchAlgorithmException
      NoSuchProviderException
      InvalidKeyException
    • configureSignatureMechanismParameters

      private void configureSignatureMechanismParameters(Signature signature)
    • update

      public void update(byte[] buf, int off, int len) throws SignatureException
      Update the digest with the specified bytes. This method is used both for signing and verifying
      Parameters:
      buf - the data buffer
      off - the offset in the data buffer
      len - the data length
      Throws:
      SignatureException - on error
    • getEncodedPKCS1

      public byte[] getEncodedPKCS1()
      Gets the bytes for the PKCS#1 object.
      Returns:
      a byte array
    • getEncodedPKCS7

      public byte[] getEncodedPKCS7()
      Gets the bytes for the PKCS7SignedData object.
      Returns:
      the bytes for the PKCS7SignedData object
    • getEncodedPKCS7

      public byte[] getEncodedPKCS7(byte[] secondDigest)
      Gets the bytes for the PKCS7SignedData object. Optionally the authenticatedAttributes in the signerInfo can also be set. If either of the parameters is null, none will be used.
      Parameters:
      secondDigest - the digest in the authenticatedAttributes
      Returns:
      the bytes for the PKCS7SignedData object
    • getEncodedPKCS7

      public byte[] getEncodedPKCS7(byte[] secondDigest, PdfSigner.CryptoStandard sigtype, ITSAClient tsaClient, Collection<byte[]> ocsp, Collection<byte[]> crlBytes)
      Gets the bytes for the PKCS7SignedData object. Optionally the authenticatedAttributes in the signerInfo can also be set, and/or a time-stamp-authority client may be provided.
      Parameters:
      secondDigest - the digest in the authenticatedAttributes
      sigtype - specifies the PKCS7 standard flavor to which created PKCS7SignedData object will adhere: either basic CMS or CAdES
      tsaClient - TSAClient - null or an optional time stamp authority client
      ocsp - collection of DER-encoded BasicOCSPResponses for the certificate in the signature certificates chain, or null if OCSP revocation data is not to be added.
      crlBytes - collection of DER-encoded CRL for certificates from the signature certificates chain, or null if CRL revocation data is not to be added.
      Returns:
      byte[] the bytes for the PKCS7SignedData object
      See Also:
    • buildUnauthenticatedAttributes

      private IASN1EncodableVector buildUnauthenticatedAttributes(byte[] timeStampToken) throws IOException
      Added by Aiken Sam, 2006-11-15, modifed by Martin Brunecky 07/12/2007 to start with the timeStampToken (signedData 1.2.840.113549.1.7.2). Token is the TSA response without response status, which is usually handled by the (vendor supplied) TSA request/response interface).
      Parameters:
      timeStampToken - byte[] - time stamp token, DER encoded signedData
      Returns:
      IASN1EncodableVector
      Throws:
      IOException - if an I/O error occurs.
    • getAuthenticatedAttributeBytes

      public byte[] getAuthenticatedAttributeBytes(byte[] secondDigest, PdfSigner.CryptoStandard sigtype, Collection<byte[]> ocsp, Collection<byte[]> crlBytes)
      When using authenticatedAttributes the authentication process is different. The document digest is generated and put inside the attribute. The signing is done over the DER encoded authenticatedAttributes. This method provides that encoding and the parameters must be exactly the same as in getEncodedPKCS7(byte[]).

      Note: do not pass in the full DER-encoded OCSPResponse object obtained from the responder, only the DER-encoded IBasicOCSPResponse value contained in the response data.

      A simple example:

       Calendar cal = Calendar.getInstance();
       PdfPKCS7 pk7 = new PdfPKCS7(key, chain, null, "SHA1", null, false);
       MessageDigest messageDigest = MessageDigest.getInstance("SHA1");
       byte[] buf = new byte[8192];
       int n;
       InputStream inp = sap.getRangeStream();
       while ((n = inp.read(buf)) > 0) {
          messageDigest.update(buf, 0, n);
       }
       byte[] hash = messageDigest.digest();
       byte[] sh = pk7.getAuthenticatedAttributeBytes(hash, cal);
       pk7.update(sh, 0, sh.length);
       byte[] sg = pk7.getEncodedPKCS7(hash, cal);
       
      Parameters:
      secondDigest - the content digest
      sigtype - specifies the PKCS7 standard flavor to which created PKCS7SignedData object will adhere: either basic CMS or CAdES
      ocsp - collection of DER-encoded BasicOCSPResponses for the certificate in the signature certificates chain, or null if OCSP revocation data is not to be added.
      crlBytes - collection of DER-encoded CRL for certificates from the signature certificates chain, or null if CRL revocation data is not to be added.
      Returns:
      the byte array representation of the authenticatedAttributes ready to be signed
      See Also:
    • getAuthenticatedAttributeSet

      private IDERSet getAuthenticatedAttributeSet(byte[] secondDigest, Collection<byte[]> ocsp, Collection<byte[]> crlBytes, PdfSigner.CryptoStandard sigtype)
      This method provides that encoding and the parameters must be exactly the same as in getEncodedPKCS7(byte[]).
      Parameters:
      secondDigest - the content digest
      Returns:
      the byte array representation of the authenticatedAttributes ready to be signed
    • verifySignatureIntegrityAndAuthenticity

      public boolean verifySignatureIntegrityAndAuthenticity() throws GeneralSecurityException
      Verifies that signature integrity is intact (or in other words that signed data wasn't modified) by checking that embedded data digest corresponds to the calculated one. Also ensures that signature is genuine and is created by the owner of private key that corresponds to the declared public certificate.

      Even though signature can be authentic and signed data integrity can be intact, one shall also always check that signed data is not only a part of PDF contents but is actually a complete PDF file. In order to check that given signature covers the current PdfDocument please use SignatureUtil.signatureCoversWholeDocument(String) method.

      Returns:
      true if the signature checks out, false otherwise
      Throws:
      GeneralSecurityException - if this signature object is not initialized properly, the passed-in signature is improperly encoded or of the wrong type, if this signature algorithm is unable to process the input data provided, if the public key is invalid or if security provider or signature algorithm are not recognized, etc.
    • verifySigAttributes

      private boolean verifySigAttributes(byte[] attr) throws GeneralSecurityException
      Throws:
      GeneralSecurityException
    • verifyTimestampImprint

      public boolean verifyTimestampImprint() throws GeneralSecurityException
      Checks if the timestamp refers to this document.
      Returns:
      true if it checks false otherwise
      Throws:
      GeneralSecurityException - on error
    • getCertificates

      public Certificate[] getCertificates()
      Get all the X.509 certificates associated with this PKCS#7 object in no particular order. Other certificates, from OCSP for example, will also be included.
      Returns:
      the X.509 certificates associated with this PKCS#7 object
    • getTimestampCertificates

      public Certificate[] getTimestampCertificates()
      Get all X.509 certificates associated with this PKCS#7 object timestamp in no particular order.
      Returns:
      Certificate array
    • getSignCertificateChain

      public Certificate[] getSignCertificateChain()
      Get the X.509 sign certificate chain associated with this PKCS#7 object. Only the certificates used for the main signature will be returned, with the signing certificate first.
      Returns:
      the X.509 certificates associated with this PKCS#7 object
    • getSigningCertificate

      public X509Certificate getSigningCertificate()
      Get the X.509 certificate actually used to sign the digest.
      Returns:
      the X.509 certificate actually used to sign the digest
    • signCertificateChain

      private void signCertificateChain()
      Helper method that creates the collection of certificates used for the main signature based on the complete list of certificates and the sign certificate.
    • getCRLs

      public Collection<CRL> getCRLs()
      Get the X.509 certificate revocation lists associated with this PKCS#7 object (stored in Signer Info).
      Returns:
      the X.509 certificate revocation lists associated with this PKCS#7 object.
    • getSignedDataCRLs

      public Collection<CRL> getSignedDataCRLs()
      Get the X.509 certificate revocation lists associated with this PKCS#7 Signed Data object.
      Returns:
      the X.509 certificate revocation lists associated with this PKCS#7 Signed Data object.
    • findCRL

      void findCRL(IASN1Sequence seq)
      Helper method that tries to construct the CRLs.
    • getSignedDataOcsps

      public Collection<IBasicOCSPResponse> getSignedDataOcsps()
      Gets the OCSP basic response collection retrieved from SignedData structure.
      Returns:
      the OCSP basic response collection.
    • getOcsp

      public IBasicOCSPResponse getOcsp()
      Gets the OCSP basic response from the SignerInfo if there is one.
      Returns:
      the OCSP basic response or null.
    • isRevocationValid

      public boolean isRevocationValid()
      Checks if OCSP revocation refers to the document signing certificate.
      Returns:
      true if it checks, false otherwise
    • findOcsp

      private void findOcsp(IASN1Sequence seq) throws IOException
      Helper method that creates the IBasicOCSPResp object.
      Parameters:
      seq - IASN1Sequence wrapper
      Throws:
      IOException - if some I/O error occurred.
    • isTsp

      public boolean isTsp()
      Check if it's a PAdES-LTV time stamp.
      Returns:
      true if it's a PAdES-LTV time stamp, false otherwise
    • getTimestampSignatureContainer

      public PdfPKCS7 getTimestampSignatureContainer()
      Retrieves inner timestamp signature container if there is one.
      Returns:
      timestamp signature container or null.
    • getTimeStampTokenInfo

      public ITSTInfo getTimeStampTokenInfo()
      Gets the timestamp token info if there is one.
      Returns:
      the timestamp token info or null
    • getTimeStampDate

      public Calendar getTimeStampDate()
      Gets the timestamp date.

      In case the signed document doesn't contain timestamp, TimestampConstants.UNDEFINED_TIMESTAMP_DATE will be returned.

      Returns:
      the timestamp date
    • getFilterSubtype

      public PdfName getFilterSubtype()
      Getter for the filter subtype.
      Returns:
      the filter subtype