/*
*
* This file is part of the iText (R) project.
Copyright (c) 1998-2017 iText Group NV
* Authors: Bruno Lowagie, Paulo Soares, et al.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License version 3
* as published by the Free Software Foundation with the addition of the
* following permission added to Section 15 as permitted in Section 7(a):
* FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY
* ITEXT GROUP. ITEXT GROUP DISCLAIMS THE WARRANTY OF NON INFRINGEMENT
* OF THIRD PARTY RIGHTS
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU Affero General Public License for more details.
* You should have received a copy of the GNU Affero General Public License
* along with this program; if not, see http://www.gnu.org/licenses or write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA, 02110-1301 USA, or download the license from the following URL:
* http://itextpdf.com/terms-of-use/
*
* The interactive user interfaces in modified source and object code versions
* of this program must display Appropriate Legal Notices, as required under
* Section 5 of the GNU Affero General Public License.
*
* In accordance with Section 7(b) of the GNU Affero General Public License,
* a covered work must retain the producer line in every PDF that is created
* or manipulated using iText.
*
* You can be released from the requirements of the license by purchasing
* a commercial license. Buying such a license is mandatory as soon as you
* develop commercial activities involving the iText software without
* disclosing the source code of your own applications.
* These activities include: offering paid services to customers as an ASP,
* serving PDFs on the fly in a web application, shipping iText with a closed
* source product.
*
* For more information, please contact iText Software Corp. at this
* address: sales@itextpdf.com
*/
package com.itextpdf.text.pdf.security;
import com.itextpdf.text.ExceptionConverter;
import com.itextpdf.text.error_messages.MessageLocalization;
import com.itextpdf.text.pdf.PdfName;
import com.itextpdf.text.pdf.security.MakeSignature.CryptoStandard;
import org.bouncycastle.asn1.*;
import org.bouncycastle.asn1.cms.Attribute;
import org.bouncycastle.asn1.cms.AttributeTable;
import org.bouncycastle.asn1.cms.ContentInfo;
import org.bouncycastle.asn1.esf.SignaturePolicyIdentifier;
import org.bouncycastle.asn1.ess.ESSCertID;
import org.bouncycastle.asn1.ess.ESSCertIDv2;
import org.bouncycastle.asn1.ess.SigningCertificate;
import org.bouncycastle.asn1.ess.SigningCertificateV2;
import org.bouncycastle.asn1.ocsp.BasicOCSPResponse;
import org.bouncycastle.asn1.ocsp.OCSPObjectIdentifiers;
import org.bouncycastle.asn1.pkcs.PKCSObjectIdentifiers;
import org.bouncycastle.asn1.tsp.MessageImprint;
import org.bouncycastle.asn1.x509.AlgorithmIdentifier;
import org.bouncycastle.cert.jcajce.JcaX509CertificateHolder;
import org.bouncycastle.cert.ocsp.BasicOCSPResp;
import org.bouncycastle.cert.ocsp.CertificateID;
import org.bouncycastle.cert.ocsp.SingleResp;
import org.bouncycastle.jce.X509Principal;
import org.bouncycastle.jce.provider.X509CertParser;
import org.bouncycastle.operator.DigestCalculator;
import org.bouncycastle.operator.jcajce.JcaDigestCalculatorProviderBuilder;
import org.bouncycastle.tsp.TimeStampToken;
import org.bouncycastle.tsp.TimeStampTokenInfo;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.math.BigInteger;
import java.security.*;
import java.security.cert.*;
import java.security.cert.Certificate;
import java.util.*;
/**
* This class does all the processing related to signing
* and verifying a PKCS#7 signature.
*/
public class PdfPKCS7 {
// Constructors for creating new signatures
/**
* Assembles all the elements needed to create a signature, except for the data.
* @param privKey the private key
* @param certChain the certificate chain
* @param interfaceDigest the interface digest
* @param hashAlgorithm the hash algorithm
* @param provider the provider or <code>null</code> for the default provider
* @param hasRSAdata <CODE>true</CODE> if the sub-filter is adbe.pkcs7.sha1
* @throws InvalidKeyException on error
* @throws NoSuchProviderException on error
* @throws NoSuchAlgorithmException on error
*/
public PdfPKCS7(PrivateKey privKey, Certificate[] certChain,
String hashAlgorithm, String provider, ExternalDigest interfaceDigest, boolean hasRSAdata)
throws InvalidKeyException, NoSuchProviderException, NoSuchAlgorithmException {
this.provider = provider;
this.interfaceDigest = interfaceDigest;
// message digest
digestAlgorithmOid = DigestAlgorithms.getAllowedDigests(hashAlgorithm);
if (digestAlgorithmOid == null)
throw new NoSuchAlgorithmException(MessageLocalization.getComposedMessage("unknown.hash.algorithm.1", hashAlgorithm));
// Copy the certificates
signCert = (X509Certificate)certChain[0];
certs = new ArrayList<Certificate>();
for (Certificate element : certChain) {
certs.add(element);
}
// initialize and add the digest algorithms.
digestalgos = new HashSet<String>();
digestalgos.add(digestAlgorithmOid);
// find the signing algorithm (RSA or DSA)
if (privKey != null) {
digestEncryptionAlgorithmOid = privKey.getAlgorithm();
if (digestEncryptionAlgorithmOid.equals("RSA")) {
digestEncryptionAlgorithmOid = SecurityIDs.ID_RSA;
}
else if (digestEncryptionAlgorithmOid.equals("DSA")) {
digestEncryptionAlgorithmOid = SecurityIDs.ID_DSA;
}
else {
throw new NoSuchAlgorithmException(MessageLocalization.getComposedMessage("unknown.key.algorithm.1", digestEncryptionAlgorithmOid));
}
}
// initialize the RSA data
if (hasRSAdata) {
RSAdata = new byte[0];
messageDigest = DigestAlgorithms.getMessageDigest(getHashAlgorithm(), provider);
}
// initialize the Signature object
if (privKey != null) {
sig = initSignature(privKey);
}
}
// Constructors for validating existing signatures
/**
* Use this constructor if you want to verify a signature using the sub-filter adbe.x509.rsa_sha1.
* @param contentsKey the /Contents key
* @param certsKey the /Cert key
* @param provider the provider or <code>null</code> for the default provider
*/
@SuppressWarnings("unchecked")
public PdfPKCS7(byte[] contentsKey, byte[] certsKey, String provider) {
try {
this.provider = provider;
X509CertParser cr = new X509CertParser();
cr.engineInit(new ByteArrayInputStream(certsKey));
certs = cr.engineReadAll();
signCerts = certs;
signCert = (X509Certificate)certs.iterator().next();
crls = new ArrayList<CRL>();
ASN1InputStream in = new ASN1InputStream(new ByteArrayInputStream(contentsKey));
digest = ((ASN1OctetString)in.readObject()).getOctets();
if (provider == null) {
sig = Signature.getInstance("SHA1withRSA");
} else {
sig = Signature.getInstance("SHA1withRSA", provider);
}
sig.initVerify(signCert.getPublicKey());
// setting the oid to SHA1withRSA
digestAlgorithmOid = "1.2.840.10040.4.3";
digestEncryptionAlgorithmOid = "1.3.36.3.3.1.2";
} catch (Exception e) {
throw new ExceptionConverter(e);
}
}
/**
* Use this constructor if you want to verify a signature.
* @param contentsKey the /Contents key
* @param filterSubtype the filtersubtype
* @param provider the provider or <code>null</code> for the default provider
*/
@SuppressWarnings({ "unchecked" })
public PdfPKCS7(byte[] contentsKey, PdfName filterSubtype, String provider) {
this.filterSubtype = filterSubtype;
isTsp = PdfName.ETSI_RFC3161.equals(filterSubtype);
isCades = PdfName.ETSI_CADES_DETACHED.equals(filterSubtype);
try {
this.provider = provider;
ASN1InputStream din = new ASN1InputStream(new ByteArrayInputStream(contentsKey));
//
// Basic checks to make sure it's a PKCS#7 SignedData Object
//
ASN1Primitive pkcs;
try {
pkcs = din.readObject();
}
catch (IOException e) {
throw new IllegalArgumentException(MessageLocalization.getComposedMessage("can.t.decode.pkcs7signeddata.object"));
}
if (!(pkcs instanceof ASN1Sequence)) {
throw new IllegalArgumentException(MessageLocalization.getComposedMessage("not.a.valid.pkcs.7.object.not.a.sequence"));
}
ASN1Sequence signedData = (ASN1Sequence)pkcs;
ASN1ObjectIdentifier objId = (ASN1ObjectIdentifier)signedData.getObjectAt(0);
if (!objId.getId().equals(SecurityIDs.ID_PKCS7_SIGNED_DATA))
throw new IllegalArgumentException(MessageLocalization.getComposedMessage("not.a.valid.pkcs.7.object.not.signed.data"));
ASN1Sequence content = (ASN1Sequence)((ASN1TaggedObject)signedData.getObjectAt(1)).getObject();
// the positions that we care are:
// 0 - version
// 1 - digestAlgorithms
// 2 - possible ID_PKCS7_DATA
// (the certificates and crls are taken out by other means)
// last - signerInfos
// the version
version = ((ASN1Integer)content.getObjectAt(0)).getValue().intValue();
// the digestAlgorithms
digestalgos = new HashSet<String>();
Enumeration<ASN1Sequence> e = ((ASN1Set)content.getObjectAt(1)).getObjects();
while (e.hasMoreElements()) {
ASN1Sequence s = e.nextElement();
ASN1ObjectIdentifier o = (ASN1ObjectIdentifier)s.getObjectAt(0);
digestalgos.add(o.getId());
}
// the possible ID_PKCS7_DATA
ASN1Sequence rsaData = (ASN1Sequence)content.getObjectAt(2);
if (rsaData.size() > 1) {
ASN1OctetString rsaDataContent = (ASN1OctetString)((ASN1TaggedObject)rsaData.getObjectAt(1)).getObject();
RSAdata = rsaDataContent.getOctets();
}
int next = 3;
while (content.getObjectAt(next) instanceof ASN1TaggedObject)
++next;
// the certificates
/*
This should work, but that's not always the case because of a bug in BouncyCastle:
*/
X509CertParser cr = new X509CertParser();
cr.engineInit(new ByteArrayInputStream(contentsKey));
certs = cr.engineReadAll();
/*
The following workaround was provided by Alfonso Massa, but it doesn't always work either.
ASN1Set certSet = null;
ASN1Set crlSet = null;
while (content.getObjectAt(next) instanceof ASN1TaggedObject) {
ASN1TaggedObject tagged = (ASN1TaggedObject)content.getObjectAt(next);
switch (tagged.getTagNo()) {
case 0:
certSet = ASN1Set.getInstance(tagged, false);
break;
case 1:
crlSet = ASN1Set.getInstance(tagged, false);
break;
default:
throw new IllegalArgumentException("unknown tag value " + tagged.getTagNo());
}
++next;
}
certs = new ArrayList<Certificate>(certSet.size());
CertificateFactory certFact = CertificateFactory.getInstance("X.509", new BouncyCastleProvider());
for (Enumeration en = certSet.getObjects(); en.hasMoreElements();) {
ASN1Primitive obj = ((ASN1Encodable)en.nextElement()).toASN1Primitive();
if (obj instanceof ASN1Sequence) {
ByteArrayInputStream stream = new ByteArrayInputStream(obj.getEncoded());
X509Certificate x509Certificate = (X509Certificate)certFact.generateCertificate(stream);
stream.close();
certs.add(x509Certificate);
}
}
*/
// the signerInfos
ASN1Set signerInfos = (ASN1Set)content.getObjectAt(next);
if (signerInfos.size() != 1)
throw new IllegalArgumentException(MessageLocalization.getComposedMessage("this.pkcs.7.object.has.multiple.signerinfos.only.one.is.supported.at.this.time"));
ASN1Sequence signerInfo = (ASN1Sequence)signerInfos.getObjectAt(0);
// the positions that we care are
// 0 - version
// 1 - the signing certificate issuer and serial number
// 2 - the digest algorithm
// 3 or 4 - digestEncryptionAlgorithm
// 4 or 5 - encryptedDigest
signerversion = ((ASN1Integer)signerInfo.getObjectAt(0)).getValue().intValue();
// Get the signing certificate
ASN1Sequence issuerAndSerialNumber = (ASN1Sequence)signerInfo.getObjectAt(1);
X509Principal issuer = new X509Principal(issuerAndSerialNumber.getObjectAt(0).toASN1Primitive().getEncoded());
BigInteger serialNumber = ((ASN1Integer)issuerAndSerialNumber.getObjectAt(1)).getValue();
for (Object element : certs) {
X509Certificate cert = (X509Certificate)element;
if (cert.getIssuerDN().equals(issuer) && serialNumber.equals(cert.getSerialNumber())) {
signCert = cert;
break;
}
}
if (signCert == null) {
throw new IllegalArgumentException(MessageLocalization.getComposedMessage("can.t.find.signing.certificate.with.serial.1",
issuer.getName() + " / " + serialNumber.toString(16)));
}
signCertificateChain();
digestAlgorithmOid = ((ASN1ObjectIdentifier)((ASN1Sequence)signerInfo.getObjectAt(2)).getObjectAt(0)).getId();
next = 3;
boolean foundCades = false;
if (signerInfo.getObjectAt(next) instanceof ASN1TaggedObject) {
ASN1TaggedObject tagsig = (ASN1TaggedObject)signerInfo.getObjectAt(next);
ASN1Set sseq = ASN1Set.getInstance(tagsig, false);
sigAttr = sseq.getEncoded();
// maybe not necessary, but we use the following line as fallback:
sigAttrDer = sseq.getEncoded(ASN1Encoding.DER);
for (int k = 0; k < sseq.size(); ++k) {
ASN1Sequence seq2 = (ASN1Sequence)sseq.getObjectAt(k);
String idSeq2 = ((ASN1ObjectIdentifier)seq2.getObjectAt(0)).getId();
if (idSeq2.equals(SecurityIDs.ID_MESSAGE_DIGEST)) {
ASN1Set set = (ASN1Set)seq2.getObjectAt(1);
digestAttr = ((ASN1OctetString)set.getObjectAt(0)).getOctets();
}
else if (idSeq2.equals(SecurityIDs.ID_ADBE_REVOCATION)) {
ASN1Set setout = (ASN1Set)seq2.getObjectAt(1);
ASN1Sequence seqout = (ASN1Sequence)setout.getObjectAt(0);
for (int j = 0; j < seqout.size(); ++j) {
ASN1TaggedObject tg = (ASN1TaggedObject)seqout.getObjectAt(j);
if (tg.getTagNo() == 0) {
ASN1Sequence seqin = (ASN1Sequence)tg.getObject();
findCRL(seqin);
}
if (tg.getTagNo() == 1) {
ASN1Sequence seqin = (ASN1Sequence)tg.getObject();
findOcsp(seqin);
}
}
}
else if (isCades && idSeq2.equals(SecurityIDs.ID_AA_SIGNING_CERTIFICATE_V1)) {
ASN1Set setout = (ASN1Set)seq2.getObjectAt(1);
ASN1Sequence seqout = (ASN1Sequence)setout.getObjectAt(0);
SigningCertificate sv2 = SigningCertificate.getInstance(seqout);
ESSCertID[] cerv2m = sv2.getCerts();
ESSCertID cerv2 = cerv2m[0];
byte[] enc2 = signCert.getEncoded();
MessageDigest m2 = new BouncyCastleDigest().getMessageDigest("SHA-1");
byte[] signCertHash = m2.digest(enc2);
byte[] hs2 = cerv2.getCertHash();
if (!Arrays.equals(signCertHash, hs2))
throw new IllegalArgumentException("Signing certificate doesn't match the ESS information.");
foundCades = true;
}
else if (isCades && idSeq2.equals(SecurityIDs.ID_AA_SIGNING_CERTIFICATE_V2)) {
ASN1Set setout = (ASN1Set)seq2.getObjectAt(1);
ASN1Sequence seqout = (ASN1Sequence)setout.getObjectAt(0);
SigningCertificateV2 sv2 = SigningCertificateV2.getInstance(seqout);
ESSCertIDv2[] cerv2m = sv2.getCerts();
ESSCertIDv2 cerv2 = cerv2m[0];
AlgorithmIdentifier ai2 = cerv2.getHashAlgorithm();
byte[] enc2 = signCert.getEncoded();
MessageDigest m2 = new BouncyCastleDigest().getMessageDigest(DigestAlgorithms.getDigest(ai2.getAlgorithm().getId()));
byte[] signCertHash = m2.digest(enc2);
byte[] hs2 = cerv2.getCertHash();
if (!Arrays.equals(signCertHash, hs2))
throw new IllegalArgumentException("Signing certificate doesn't match the ESS information.");
foundCades = true;
}
}
if (digestAttr == null)
throw new IllegalArgumentException(MessageLocalization.getComposedMessage("authenticated.attribute.is.missing.the.digest"));
++next;
}
if (isCades && !foundCades)
throw new IllegalArgumentException("CAdES ESS information missing.");
digestEncryptionAlgorithmOid = ((ASN1ObjectIdentifier)((ASN1Sequence)signerInfo.getObjectAt(next++)).getObjectAt(0)).getId();
digest = ((ASN1OctetString)signerInfo.getObjectAt(next++)).getOctets();
if (next < signerInfo.size() && signerInfo.getObjectAt(next) instanceof ASN1TaggedObject) {
ASN1TaggedObject taggedObject = (ASN1TaggedObject) signerInfo.getObjectAt(next);
ASN1Set unat = ASN1Set.getInstance(taggedObject, false);
AttributeTable attble = new AttributeTable(unat);
Attribute ts = attble.get(PKCSObjectIdentifiers.id_aa_signatureTimeStampToken);
if (ts != null && ts.getAttrValues().size() > 0) {
ASN1Set attributeValues = ts.getAttrValues();
ASN1Sequence tokenSequence = ASN1Sequence.getInstance(attributeValues.getObjectAt(0));
ContentInfo contentInfo = new ContentInfo(tokenSequence);
this.timeStampToken = new TimeStampToken(contentInfo);
}
}
if (isTsp) {
ContentInfo contentInfoTsp = new ContentInfo(signedData);
this.timeStampToken = new TimeStampToken(contentInfoTsp);
TimeStampTokenInfo info = timeStampToken.getTimeStampInfo();
String algOID = info.getMessageImprintAlgOID().getId();
messageDigest = DigestAlgorithms.getMessageDigestFromOid(algOID, null);
}
else {
if (RSAdata != null || digestAttr != null) {
if (PdfName.ADBE_PKCS7_SHA1.equals(getFilterSubtype())) {
messageDigest = DigestAlgorithms.getMessageDigest("SHA1", provider);
}
else {
messageDigest = DigestAlgorithms.getMessageDigest(getHashAlgorithm(), provider);
}
encContDigest = DigestAlgorithms.getMessageDigest(getHashAlgorithm(), provider);
}
sig = initSignature(signCert.getPublicKey());
}
}
catch (Exception e) {
throw new ExceptionConverter(e);
}
}
// Encryption provider
/** The encryption provider, e.g. "BC" if you use BouncyCastle. */
private String provider;
// Signature info
private SignaturePolicyIdentifier signaturePolicyIdentifier;
/** Holds value of property signName. */
private String signName;
/** Holds value of property reason. */
private String reason;
/** Holds value of property location. */
private String location;
/** Holds value of property signDate. */
private Calendar signDate;
public void setSignaturePolicy(SignaturePolicyInfo signaturePolicy) {
this.signaturePolicyIdentifier = signaturePolicy.toSignaturePolicyIdentifier();
}
public void setSignaturePolicy(SignaturePolicyIdentifier signaturePolicy) {
this.signaturePolicyIdentifier = signaturePolicy;
}
/**
* Getter for property sigName.
* @return Value of property sigName.
*/
public String getSignName() {
return this.signName;
}
/**
* Setter for property sigName.
* @param signName New value of property sigName.
*/
public void setSignName(String signName) {
this.signName = signName;
}
/**
* Getter for property reason.
* @return Value of property reason.
*/
public String getReason() {
return this.reason;
}
/**
* Setter for property reason.
* @param reason New value of property reason.
*/
public void setReason(String reason) {
this.reason = reason;
}
/**
* Getter for property location.
* @return Value of property location.
*/
public String getLocation() {
return this.location;
}
/**
* Setter for property location.
* @param location New value of property location.
*/
public void setLocation(String location) {
this.location = location;
}
/**
* Getter for property signDate.
* @return Value of property signDate.
*/
public Calendar getSignDate() {
Calendar dt = getTimeStampDate();
if (dt == null)
return this.signDate;
else
return dt;
}
/**
* Setter for property signDate.
* @param signDate New value of property signDate.
*/
public void setSignDate(Calendar signDate) {
this.signDate = signDate;
}
// version info
/** Version of the PKCS#7 object */
private int version = 1;
/** Version of the PKCS#7 "SignerInfo" object. */
private int signerversion = 1;
/**
* Get the version of the PKCS#7 object.
* @return the version of the PKCS#7 object.
*/
public int getVersion() {
return version;
}
/**
* Get the version of the PKCS#7 "SignerInfo" object.
* @return the version of the PKCS#7 "SignerInfo" object.
*/
public int getSigningInfoVersion() {
return signerversion;
}
// Message digest algorithm
/** The ID of the digest algorithm, e.g. "2.16.840.1.101.3.4.2.1". */
private String digestAlgorithmOid;
/** The object that will create the digest */
private MessageDigest messageDigest;
/** The digest algorithms */
private Set<String> digestalgos;
/** The digest attributes */
private byte[] digestAttr;
private PdfName filterSubtype;
/**
* Getter for the ID of the digest algorithm, e.g. "2.16.840.1.101.3.4.2.1"
*/
public String getDigestAlgorithmOid() {
return digestAlgorithmOid;
}
/**
* Returns the name of the digest algorithm, e.g. "SHA256".
* @return the digest algorithm name, e.g. "SHA256"
*/
public String getHashAlgorithm() {
return DigestAlgorithms.getDigest(digestAlgorithmOid);
}
// Encryption algorithm
/** The encryption algorithm. */
private String digestEncryptionAlgorithmOid;
/**
* Getter for the digest encryption algorithm
*/
public String getDigestEncryptionAlgorithmOid() {
return digestEncryptionAlgorithmOid;
}
/**
* Get the algorithm used to calculate the message digest, e.g. "SHA1withRSA".
* @return the algorithm used to calculate the message digest
*/
public String getDigestAlgorithm() {
return getHashAlgorithm() + "with" + getEncryptionAlgorithm();
}
/*
* DIGITAL SIGNATURE CREATION
*/
private ExternalDigest interfaceDigest;
// The signature is created externally
/** The signed digest if created outside this class */
private byte externalDigest[];
/** External RSA data */
private byte externalRSAdata[];
/**
* Sets the digest/signature to an external calculated value.
* @param digest the digest. This is the actual signature
* @param RSAdata the extra data that goes into the data tag in PKCS#7
* @param digestEncryptionAlgorithm the encryption algorithm. It may must be <CODE>null</CODE> if the <CODE>digest</CODE>
* is also <CODE>null</CODE>. If the <CODE>digest</CODE> is not <CODE>null</CODE>
* then it may be "RSA" or "DSA"
*/
public void setExternalDigest(byte digest[], byte RSAdata[], String digestEncryptionAlgorithm) {
externalDigest = digest;
externalRSAdata = RSAdata;
if (digestEncryptionAlgorithm != null) {
if (digestEncryptionAlgorithm.equals("RSA")) {
this.digestEncryptionAlgorithmOid = SecurityIDs.ID_RSA;
}
else if (digestEncryptionAlgorithm.equals("DSA")) {
this.digestEncryptionAlgorithmOid = SecurityIDs.ID_DSA;
}
else if (digestEncryptionAlgorithm.equals("ECDSA")) {
this.digestEncryptionAlgorithmOid = SecurityIDs.ID_ECDSA;
}
else
throw new ExceptionConverter(new NoSuchAlgorithmException(MessageLocalization.getComposedMessage("unknown.key.algorithm.1", digestEncryptionAlgorithm)));
}
}
// The signature is created internally
/** Class from the Java SDK that provides the functionality of a digital signature algorithm. */
private Signature sig;
/** The signed digest as calculated by this class (or extracted from an existing PDF) */
private byte[] digest;
/** The RSA data */
private byte[] RSAdata;
// Signing functionality.
private Signature initSignature(PrivateKey key) throws NoSuchAlgorithmException, NoSuchProviderException, InvalidKeyException {
Signature signature;
if (provider == null)
signature = Signature.getInstance(getDigestAlgorithm());
else
signature = Signature.getInstance(getDigestAlgorithm(), provider);
signature.initSign(key);
return signature;
}
private Signature initSignature(PublicKey key) throws NoSuchAlgorithmException, NoSuchProviderException, InvalidKeyException {
String digestAlgorithm = getDigestAlgorithm();
if (PdfName.ADBE_X509_RSA_SHA1.equals(getFilterSubtype()))
digestAlgorithm = "SHA1withRSA";
Signature signature;
if (provider == null)
signature = Signature.getInstance(digestAlgorithm);
else
signature = Signature.getInstance(digestAlgorithm, provider);
signature.initVerify(key);
return signature;
}
/**
* Update the digest with the specified bytes.
* This method is used both for signing and verifying
* @param buf the data buffer
* @param off the offset in the data buffer
* @param len the data length
* @throws SignatureException on error
*/
public void update(byte[] buf, int off, int len) throws SignatureException {
if (RSAdata != null || digestAttr != null || isTsp)
messageDigest.update(buf, off, len);
else
sig.update(buf, off, len);
}
// adbe.x509.rsa_sha1 (PKCS#1)
/**
* Gets the bytes for the PKCS#1 object.
* @return a byte array
*/
public byte[] getEncodedPKCS1() {
try {
if (externalDigest != null)
digest = externalDigest;
else
digest = sig.sign();
ByteArrayOutputStream bOut = new ByteArrayOutputStream();
ASN1OutputStream dout = new ASN1OutputStream(bOut);
dout.writeObject(new DEROctetString(digest));
dout.close();
return bOut.toByteArray();
}
catch (Exception e) {
throw new ExceptionConverter(e);
}
}
// other subfilters (PKCS#7)
/**
* Gets the bytes for the PKCS7SignedData object.
* @return the bytes for the PKCS7SignedData object
*/
public byte[] getEncodedPKCS7() {
return getEncodedPKCS7(null, null, null, null, CryptoStandard.CMS);
}
/**
* Gets the bytes for the PKCS7SignedData object. Optionally the authenticatedAttributes
* in the signerInfo can also be set. If either of the parameters is <CODE>null</CODE>, none will be used.
* @param secondDigest the digest in the authenticatedAttributes
* @return the bytes for the PKCS7SignedData object
*/
public byte[] getEncodedPKCS7(byte secondDigest[]) {
return getEncodedPKCS7(secondDigest, null, null, null, CryptoStandard.CMS);
}
/**
* Gets the bytes for the PKCS7SignedData object. Optionally the authenticatedAttributes
* in the signerInfo can also be set, OR a time-stamp-authority client
* may be provided.
* @param secondDigest the digest in the authenticatedAttributes
* @param tsaClient TSAClient - null or an optional time stamp authority client
* @return byte[] the bytes for the PKCS7SignedData object
* @since 2.1.6
*/
public byte[] getEncodedPKCS7(byte secondDigest[], TSAClient tsaClient, byte[] ocsp, Collection<byte[]> crlBytes, CryptoStandard sigtype) {
try {
if (externalDigest != null) {
digest = externalDigest;
if (RSAdata != null)
RSAdata = externalRSAdata;
}
else if (externalRSAdata != null && RSAdata != null) {
RSAdata = externalRSAdata;
sig.update(RSAdata);
digest = sig.sign();
}
else {
if (RSAdata != null) {
RSAdata = messageDigest.digest();
sig.update(RSAdata);
}
digest = sig.sign();
}
// Create the set of Hash algorithms
ASN1EncodableVector digestAlgorithms = new ASN1EncodableVector();
for (Object element : digestalgos) {
ASN1EncodableVector algos = new ASN1EncodableVector();
algos.add(new ASN1ObjectIdentifier((String)element));
algos.add(DERNull.INSTANCE);
digestAlgorithms.add(new DERSequence(algos));
}
// Create the contentInfo.
ASN1EncodableVector v = new ASN1EncodableVector();
v.add(new ASN1ObjectIdentifier(SecurityIDs.ID_PKCS7_DATA));
if (RSAdata != null)
v.add(new DERTaggedObject(0, new DEROctetString(RSAdata)));
DERSequence contentinfo = new DERSequence(v);
// Get all the certificates
//
v = new ASN1EncodableVector();
for (Object element : certs) {
ASN1InputStream tempstream = new ASN1InputStream(new ByteArrayInputStream(((X509Certificate)element).getEncoded()));
v.add(tempstream.readObject());
}
DERSet dercertificates = new DERSet(v);
// Create signerinfo structure.
//
ASN1EncodableVector signerinfo = new ASN1EncodableVector();
// Add the signerInfo version
//
signerinfo.add(new ASN1Integer(signerversion));
v = new ASN1EncodableVector();
v.add(CertificateInfo.getIssuer(signCert.getTBSCertificate()));
v.add(new ASN1Integer(signCert.getSerialNumber()));
signerinfo.add(new DERSequence(v));
// Add the digestAlgorithm
v = new ASN1EncodableVector();
v.add(new ASN1ObjectIdentifier(digestAlgorithmOid));
v.add(new DERNull());
signerinfo.add(new DERSequence(v));
// add the authenticated attribute if present
if (secondDigest != null) {
signerinfo.add(new DERTaggedObject(false, 0, getAuthenticatedAttributeSet(secondDigest, ocsp, crlBytes, sigtype)));
}
// Add the digestEncryptionAlgorithm
v = new ASN1EncodableVector();
v.add(new ASN1ObjectIdentifier(digestEncryptionAlgorithmOid));
v.add(new DERNull());
signerinfo.add(new DERSequence(v));
// Add the digest
signerinfo.add(new DEROctetString(digest));
// When requested, go get and add the timestamp. May throw an exception.
// Added by Martin Brunecky, 07/12/2007 folowing Aiken Sam, 2006-11-15
// Sam found Adobe expects time-stamped SHA1-1 of the encrypted digest
if (tsaClient != null) {
byte[] tsImprint = tsaClient.getMessageDigest().digest(digest);
byte[] tsToken = tsaClient.getTimeStampToken(tsImprint);
if (tsToken != null) {
ASN1EncodableVector unauthAttributes = buildUnauthenticatedAttributes(tsToken);
if (unauthAttributes != null) {
signerinfo.add(new DERTaggedObject(false, 1, new DERSet(unauthAttributes)));
}
}
}
// Finally build the body out of all the components above
ASN1EncodableVector body = new ASN1EncodableVector();
body.add(new ASN1Integer(version));
body.add(new DERSet(digestAlgorithms));
body.add(contentinfo);
body.add(new DERTaggedObject(false, 0, dercertificates));
// Only allow one signerInfo
body.add(new DERSet(new DERSequence(signerinfo)));
// Now we have the body, wrap it in it's PKCS7Signed shell
// and return it
//
ASN1EncodableVector whole = new ASN1EncodableVector();
whole.add(new ASN1ObjectIdentifier(SecurityIDs.ID_PKCS7_SIGNED_DATA));
whole.add(new DERTaggedObject(0, new DERSequence(body)));
ByteArrayOutputStream bOut = new ByteArrayOutputStream();
ASN1OutputStream dout = new ASN1OutputStream(bOut);
dout.writeObject(new DERSequence(whole));
dout.close();
return bOut.toByteArray();
}
catch (Exception e) {
throw new ExceptionConverter(e);
}
}
/**
* 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).
* @param timeStampToken byte[] - time stamp token, DER encoded signedData
* @return ASN1EncodableVector
* @throws IOException
*/
private ASN1EncodableVector buildUnauthenticatedAttributes(byte[] timeStampToken) throws IOException {
if (timeStampToken == null)
return null;
// @todo: move this together with the rest of the defintions
String ID_TIME_STAMP_TOKEN = "1.2.840.113549.1.9.16.2.14"; // RFC 3161 id-aa-timeStampToken
ASN1InputStream tempstream = new ASN1InputStream(new ByteArrayInputStream(timeStampToken));
ASN1EncodableVector unauthAttributes = new ASN1EncodableVector();
ASN1EncodableVector v = new ASN1EncodableVector();
v.add(new ASN1ObjectIdentifier(ID_TIME_STAMP_TOKEN)); // id-aa-timeStampToken
ASN1Sequence seq = (ASN1Sequence) tempstream.readObject();
v.add(new DERSet(seq));
unauthAttributes.add(new DERSequence(v));
return unauthAttributes;
}
// Authenticated attributes
/**
* 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 {@link #getEncodedPKCS7(byte[])}.
* <p>
* A simple example:
* <p>
* <pre>
* 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);
* </pre>
* @param secondDigest the content digest
* @return the byte array representation of the authenticatedAttributes ready to be signed
*/
public byte[] getAuthenticatedAttributeBytes(byte secondDigest[], byte[] ocsp, Collection<byte[]> crlBytes, CryptoStandard sigtype) {
try {
return getAuthenticatedAttributeSet(secondDigest, ocsp, crlBytes, sigtype).getEncoded(ASN1Encoding.DER);
}
catch (Exception e) {
throw new ExceptionConverter(e);
}
}
/**
* This method provides that encoding and the parameters must be
* exactly the same as in {@link #getEncodedPKCS7(byte[])}.
*
* @param secondDigest the content digest
* @return the byte array representation of the authenticatedAttributes ready to be signed
*/
private DERSet getAuthenticatedAttributeSet(byte secondDigest[], byte[] ocsp, Collection<byte[]> crlBytes, CryptoStandard sigtype) {
try {
ASN1EncodableVector attribute = new ASN1EncodableVector();
ASN1EncodableVector v = new ASN1EncodableVector();
v.add(new ASN1ObjectIdentifier(SecurityIDs.ID_CONTENT_TYPE));
v.add(new DERSet(new ASN1ObjectIdentifier(SecurityIDs.ID_PKCS7_DATA)));
attribute.add(new DERSequence(v));
v = new ASN1EncodableVector();
v.add(new ASN1ObjectIdentifier(SecurityIDs.ID_MESSAGE_DIGEST));
v.add(new DERSet(new DEROctetString(secondDigest)));
attribute.add(new DERSequence(v));
boolean haveCrl = false;
if (crlBytes != null) {
for (byte[] bCrl : crlBytes) {
if (bCrl != null) {
haveCrl = true;
break;
}
}
}
if (ocsp != null || haveCrl) {
v = new ASN1EncodableVector();
v.add(new ASN1ObjectIdentifier(SecurityIDs.ID_ADBE_REVOCATION));
ASN1EncodableVector revocationV = new ASN1EncodableVector();
if (haveCrl) {
ASN1EncodableVector v2 = new ASN1EncodableVector();
for (byte[] bCrl : crlBytes) {
if (bCrl == null)
continue;
ASN1InputStream t = new ASN1InputStream(new ByteArrayInputStream(bCrl));
v2.add(t.readObject());
}
revocationV.add(new DERTaggedObject(true, 0, new DERSequence(v2)));
}
if (ocsp != null) {
DEROctetString doctet = new DEROctetString(ocsp);
ASN1EncodableVector vo1 = new ASN1EncodableVector();
ASN1EncodableVector v2 = new ASN1EncodableVector();
v2.add(OCSPObjectIdentifiers.id_pkix_ocsp_basic);
v2.add(doctet);
ASN1Enumerated den = new ASN1Enumerated(0);
ASN1EncodableVector v3 = new ASN1EncodableVector();
v3.add(den);
v3.add(new DERTaggedObject(true, 0, new DERSequence(v2)));
vo1.add(new DERSequence(v3));
revocationV.add(new DERTaggedObject(true, 1, new DERSequence(vo1)));
}
v.add(new DERSet(new DERSequence(revocationV)));
attribute.add(new DERSequence(v));
}
if (sigtype == CryptoStandard.CADES) {
v = new ASN1EncodableVector();
v.add(new ASN1ObjectIdentifier(SecurityIDs.ID_AA_SIGNING_CERTIFICATE_V2));
ASN1EncodableVector aaV2 = new ASN1EncodableVector();
String sha256Oid = DigestAlgorithms.getAllowedDigests(DigestAlgorithms.SHA256);
// If we look into X.690-0207, clause 11.5, we can see that using DER all the components of a sequence having
// default values shall not be included. According to RFC 5035, 5.4.1.1, definition of ESSCertIDv2, default
// AlgorithmIdentifier is sha256.
if (!sha256Oid.equals(digestAlgorithmOid)) {
AlgorithmIdentifier algoId = new AlgorithmIdentifier(new ASN1ObjectIdentifier(digestAlgorithmOid));
aaV2.add(algoId);
}
MessageDigest md = interfaceDigest.getMessageDigest(getHashAlgorithm());
byte[] dig = md.digest(signCert.getEncoded());
aaV2.add(new DEROctetString(dig));
v.add(new DERSet(new DERSequence(new DERSequence(new DERSequence(aaV2)))));
attribute.add(new DERSequence(v));
}
if (signaturePolicyIdentifier != null) {
attribute.add(new Attribute(PKCSObjectIdentifiers.id_aa_ets_sigPolicyId, new DERSet(signaturePolicyIdentifier)));
}
return new DERSet(attribute);
}
catch (Exception e) {
throw new ExceptionConverter(e);
}
}
/*
* DIGITAL SIGNATURE VERIFICATION
*/
/** Signature attributes */
private byte[] sigAttr;
/** Signature attributes (maybe not necessary, but we use it as fallback) */
private byte[] sigAttrDer;
/** encrypted digest */
private MessageDigest encContDigest; // Stefan Santesson
/** Indicates if a signature has already been verified */
private boolean verified;
/** The result of the verification */
private boolean verifyResult;
// verification
/**
* Verify the digest.
* @throws SignatureException on error
* @return <CODE>true</CODE> if the signature checks out, <CODE>false</CODE> otherwise
* @throws java.security.GeneralSecurityException
*/
public boolean verify() throws GeneralSecurityException {
if (verified)
return verifyResult;
if (isTsp) {
TimeStampTokenInfo info = timeStampToken.getTimeStampInfo();
MessageImprint imprint = info.toASN1Structure().getMessageImprint();
byte[] md = messageDigest.digest();
byte[] imphashed = imprint.getHashedMessage();
verifyResult = Arrays.equals(md, imphashed);
}
else {
if (sigAttr != null || sigAttrDer != null) {
final byte [] msgDigestBytes = messageDigest.digest();
boolean verifyRSAdata = true;
// Stefan Santesson fixed a bug, keeping the code backward compatible
boolean encContDigestCompare = false;
if (RSAdata != null) {
verifyRSAdata = Arrays.equals(msgDigestBytes, RSAdata);
encContDigest.update(RSAdata);
encContDigestCompare = Arrays.equals(encContDigest.digest(), digestAttr);
}
boolean absentEncContDigestCompare = Arrays.equals(msgDigestBytes, digestAttr);
boolean concludingDigestCompare = absentEncContDigestCompare || encContDigestCompare;
boolean sigVerify = verifySigAttributes(sigAttr) || verifySigAttributes(sigAttrDer);
verifyResult = concludingDigestCompare && sigVerify && verifyRSAdata;
}
else {
if (RSAdata != null)
sig.update(messageDigest.digest());
verifyResult = sig.verify(digest);
}
}
verified = true;
return verifyResult;
}
private boolean verifySigAttributes(byte[] attr) throws GeneralSecurityException {
Signature signature = initSignature(signCert.getPublicKey());
signature.update(attr);
return signature.verify(digest);
}
/**
* Checks if the timestamp refers to this document.
* @return true if it checks false otherwise
* @throws GeneralSecurityException on error
* @since 2.1.6
*/
public boolean verifyTimestampImprint() throws GeneralSecurityException {
if (timeStampToken == null)
return false;
TimeStampTokenInfo info = timeStampToken.getTimeStampInfo();
MessageImprint imprint = info.toASN1Structure().getMessageImprint();
String algOID = info.getMessageImprintAlgOID().getId();
byte[] md = new BouncyCastleDigest().getMessageDigest(DigestAlgorithms.getDigest(algOID)).digest(digest);
byte[] imphashed = imprint.getHashedMessage();
boolean res = Arrays.equals(md, imphashed);
return res;
}
// Certificates
/** All the X.509 certificates in no particular order. */
private Collection<Certificate> certs;
/** All the X.509 certificates used for the main signature. */
private Collection<Certificate> signCerts;
/** The X.509 certificate that is used to sign the digest. */
private X509Certificate signCert;
/**
* 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.
* @return the X.509 certificates associated with this PKCS#7 object
*/
public Certificate[] getCertificates() {
return certs.toArray(new X509Certificate[certs.size()]);
}
/**
* 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.
* @return the X.509 certificates associated with this PKCS#7 object
* @since 2.1.6
*/
public Certificate[] getSignCertificateChain() {
return signCerts.toArray(new X509Certificate[signCerts.size()]);
}
/**
* Get the X.509 certificate actually used to sign the digest.
* @return the X.509 certificate actually used to sign the digest
*/
public X509Certificate getSigningCertificate() {
return signCert;
}
/**
* Helper method that creates the collection of certificates
* used for the main signature based on the complete list
* of certificates and the sign certificate.
*/
private void signCertificateChain() {
ArrayList<Certificate> cc = new ArrayList<Certificate>();
cc.add(signCert);
ArrayList<Certificate> oc = new ArrayList<Certificate>(certs);
for (int k = 0; k < oc.size(); ++k) {
if (signCert.equals(oc.get(k))) {
oc.remove(k);
--k;
continue;
}
}
boolean found = true;
while (found) {
X509Certificate v = (X509Certificate)cc.get(cc.size() - 1);
found = false;
for (int k = 0; k < oc.size(); ++k) {
X509Certificate issuer = (X509Certificate)oc.get(k);
try {
if (provider == null)
v.verify(issuer.getPublicKey());
else
v.verify(issuer.getPublicKey(), provider);
found = true;
cc.add(oc.get(k));
oc.remove(k);
break;
}
catch (Exception e) {
}
}
}
signCerts = cc;
}
// Certificate Revocation Lists
private Collection<CRL> crls;
/**
* Get the X.509 certificate revocation lists associated with this PKCS#7 object
* @return the X.509 certificate revocation lists associated with this PKCS#7 object
*/
public Collection<CRL> getCRLs() {
return crls;
}
/**
* Helper method that tries to construct the CRLs.
*/
private void findCRL(ASN1Sequence seq) {
try {
crls = new ArrayList<CRL>();
for (int k = 0; k < seq.size(); ++k) {
ByteArrayInputStream ar = new ByteArrayInputStream(seq.getObjectAt(k).toASN1Primitive().getEncoded(ASN1Encoding.DER));
CertificateFactory cf = CertificateFactory.getInstance("X.509");
X509CRL crl = (X509CRL)cf.generateCRL(ar);
crls.add(crl);
}
}
catch (Exception ex) {
// ignore
}
}
// Online Certificate Status Protocol
/** BouncyCastle BasicOCSPResp */
private BasicOCSPResp basicResp;
/**
* Gets the OCSP basic response if there is one.
* @return the OCSP basic response or null
* @since 2.1.6
*/
public BasicOCSPResp getOcsp() {
return basicResp;
}
/**
* Checks if OCSP revocation refers to the document signing certificate.
* @return true if it checks, false otherwise
* @since 2.1.6
*/
public boolean isRevocationValid() {
if (basicResp == null)
return false;
if (signCerts.size() < 2)
return false;
try {
X509Certificate[] cs = (X509Certificate[])getSignCertificateChain();
SingleResp sr = basicResp.getResponses()[0];
CertificateID cid = sr.getCertID();
DigestCalculator digestalg = new JcaDigestCalculatorProviderBuilder().build().get(new AlgorithmIdentifier(cid.getHashAlgOID(), DERNull.INSTANCE));
X509Certificate sigcer = getSigningCertificate();
X509Certificate isscer = cs[1];
CertificateID tis = new CertificateID(
digestalg, new JcaX509CertificateHolder(isscer), sigcer.getSerialNumber());
return tis.equals(cid);
}
catch (Exception ex) {
}
return false;
}
/**
* Helper method that creates the BasicOCSPResp object.
* @param seq
* @throws IOException
*/
private void findOcsp(ASN1Sequence seq) throws IOException {
basicResp = null;
boolean ret = false;
while (true) {
if (seq.getObjectAt(0) instanceof ASN1ObjectIdentifier
&& ((ASN1ObjectIdentifier)seq.getObjectAt(0)).getId().equals(OCSPObjectIdentifiers.id_pkix_ocsp_basic.getId())) {
break;
}
ret = true;
for (int k = 0; k < seq.size(); ++k) {
if (seq.getObjectAt(k) instanceof ASN1Sequence) {
seq = (ASN1Sequence)seq.getObjectAt(0);
ret = false;
break;
}
if (seq.getObjectAt(k) instanceof ASN1TaggedObject) {
ASN1TaggedObject tag = (ASN1TaggedObject)seq.getObjectAt(k);
if (tag.getObject() instanceof ASN1Sequence) {
seq = (ASN1Sequence)tag.getObject();
ret = false;
break;
}
else
return;
}
}
if (ret)
return;
}
ASN1OctetString os = (ASN1OctetString)seq.getObjectAt(1);
ASN1InputStream inp = new ASN1InputStream(os.getOctets());
BasicOCSPResponse resp = BasicOCSPResponse.getInstance(inp.readObject());
basicResp = new BasicOCSPResp(resp);
}
// Time Stamps
/** True if there's a PAdES LTV time stamp. */
private boolean isTsp;
/** True if it's a CAdES signature type. */
private boolean isCades;
/** BouncyCastle TimeStampToken. */
private TimeStampToken timeStampToken;
/**
* Check if it's a PAdES-LTV time stamp.
* @return true if it's a PAdES-LTV time stamp, false otherwise
*/
public boolean isTsp() {
return isTsp;
}
/**
* Gets the timestamp token if there is one.
* @return the timestamp token or null
* @since 2.1.6
*/
public TimeStampToken getTimeStampToken() {
return timeStampToken;
}
/**
* Gets the timestamp date
* @return a date
* @since 2.1.6
*/
public Calendar getTimeStampDate() {
if (timeStampToken == null)
return null;
Calendar cal = new GregorianCalendar();
Date date = timeStampToken.getTimeStampInfo().getGenTime();
cal.setTime(date);
return cal;
}
/**
* Returns the filter subtype.
*/
public PdfName getFilterSubtype() {
return filterSubtype;
}
/**
* Returns the encryption algorithm
* @return the name of an encryption algorithm
*/
public String getEncryptionAlgorithm() {
String encryptAlgo = EncryptionAlgorithms.getAlgorithm(digestEncryptionAlgorithmOid);
if (encryptAlgo == null)
encryptAlgo = digestEncryptionAlgorithmOid;
return encryptAlgo;
}
}