SignerInformation(
SignerInfo info,
ASN1ObjectIdentifier contentType,
CMSProcessable content,
IntDigestCalculator digestCalculator,
SignatureAlgorithmIdentifierFinder sigAlgFinder) {
this.info = info;
this.contentType = contentType;
this.sigAlgFinder = sigAlgFinder;
this.isCounterSignature = contentType == null;
SignerIdentifier s = info.getSID();
if (s.isTagged()) {
ASN1OctetString octs = ASN1OctetString.getInstance(s.getId());
sid = new SignerId(octs.getOctets());
} else {
IssuerAndSerialNumber iAnds = IssuerAndSerialNumber.getInstance(s.getId());
sid = new SignerId(iAnds.getName(), iAnds.getSerialNumber().getValue());
}
this.digestAlgorithm = info.getDigestAlgorithm();
this.signedAttributeSet = info.getAuthenticatedAttributes();
this.unsignedAttributeSet = info.getUnauthenticatedAttributes();
this.encryptionAlgorithm = info.getDigestEncryptionAlgorithm();
this.signature = info.getEncryptedDigest().getOctets();
this.content = content;
this.digestCalculator = digestCalculator;
}
@Override
protected void onDocumentSigned(byte[] byteArray) {
try {
InputStream inputStream = new ByteArrayInputStream(byteArray);
PDDocument document = PDDocument.load(inputStream);
List<PDSignature> signatures = document.getSignatureDictionaries();
assertEquals(1, signatures.size());
for (PDSignature pdSignature : signatures) {
byte[] contents = pdSignature.getContents(byteArray);
byte[] signedContent = pdSignature.getSignedContent(byteArray);
logger.info("Byte range : " + Arrays.toString(pdSignature.getByteRange()));
// IOUtils.write(contents, new FileOutputStream("sig.p7s"));
ASN1InputStream asn1sInput = new ASN1InputStream(contents);
ASN1Sequence asn1Seq = (ASN1Sequence) asn1sInput.readObject();
logger.info("SEQ : " + asn1Seq.toString());
ASN1ObjectIdentifier oid = ASN1ObjectIdentifier.getInstance(asn1Seq.getObjectAt(0));
assertEquals(PKCSObjectIdentifiers.signedData, oid);
SignedData signedData =
SignedData.getInstance(DERTaggedObject.getInstance(asn1Seq.getObjectAt(1)).getObject());
ASN1Set digestAlgorithmSet = signedData.getDigestAlgorithms();
ASN1ObjectIdentifier oidDigestAlgo =
ASN1ObjectIdentifier.getInstance(
ASN1Sequence.getInstance(digestAlgorithmSet.getObjectAt(0)).getObjectAt(0));
DigestAlgorithm digestAlgorithm = DigestAlgorithm.forOID(oidDigestAlgo.getId());
logger.info("DIGEST ALGO : " + digestAlgorithm);
ContentInfo encapContentInfo = signedData.getEncapContentInfo();
ASN1ObjectIdentifier contentTypeOID = encapContentInfo.getContentType();
logger.info("ENCAPSULATED CONTENT INFO TYPE : " + contentTypeOID);
assertEquals(PKCSObjectIdentifiers.data, contentTypeOID);
ASN1Encodable content = encapContentInfo.getContent();
logger.info("ENCAPSULATED CONTENT INFO CONTENT : " + content);
assertNull(content);
List<X509Certificate> certificates = extractCertificates(signedData);
ASN1Set signerInfosAsn1 = signedData.getSignerInfos();
logger.info("SIGNER INFO ASN1 : " + signerInfosAsn1.toString());
SignerInfo signedInfo =
SignerInfo.getInstance(ASN1Sequence.getInstance(signerInfosAsn1.getObjectAt(0)));
ASN1Set authenticatedAttributeSet = signedInfo.getAuthenticatedAttributes();
logger.info("AUTHENTICATED ATTR : " + authenticatedAttributeSet);
List<ASN1ObjectIdentifier> attributeOids = new ArrayList<ASN1ObjectIdentifier>();
for (int i = 0; i < authenticatedAttributeSet.size(); i++) {
Attribute attribute = Attribute.getInstance(authenticatedAttributeSet.getObjectAt(i));
attributeOids.add(attribute.getAttrType());
}
logger.info("List of OID for Auth Attrb : " + attributeOids);
Attribute attributeDigest = Attribute.getInstance(authenticatedAttributeSet.getObjectAt(1));
assertEquals(PKCSObjectIdentifiers.pkcs_9_at_messageDigest, attributeDigest.getAttrType());
ASN1OctetString asn1ObjString =
ASN1OctetString.getInstance(attributeDigest.getAttrValues().getObjectAt(0));
String embeddedDigest = Base64.encode(asn1ObjString.getOctets());
logger.info("MESSAGE DIGEST : " + embeddedDigest);
byte[] digestSignedContent = DSSUtils.digest(digestAlgorithm, signedContent);
String computedDigestSignedContentEncodeBase64 = Base64.encode(digestSignedContent);
logger.info(
"COMPUTED DIGEST SIGNED CONTENT BASE64 : " + computedDigestSignedContentEncodeBase64);
assertEquals(embeddedDigest, computedDigestSignedContentEncodeBase64);
SignerIdentifier sid = signedInfo.getSID();
logger.info("SIGNER IDENTIFIER : " + sid.getId());
IssuerAndSerialNumber issuerAndSerialNumber =
IssuerAndSerialNumber.getInstance(signedInfo.getSID());
ASN1Integer signerSerialNumber = issuerAndSerialNumber.getSerialNumber();
logger.info(
"ISSUER AND SN : " + issuerAndSerialNumber.getName() + " " + signerSerialNumber);
BigInteger serial = issuerAndSerialNumber.getSerialNumber().getValue();
X509Certificate signerCertificate = null;
for (X509Certificate x509Certificate : certificates) {
if (serial.equals(x509Certificate.getSerialNumber())) {
signerCertificate = x509Certificate;
}
}
assertNotNull(signerCertificate);
String algorithm = signerCertificate.getPublicKey().getAlgorithm();
EncryptionAlgorithm encryptionAlgorithm = EncryptionAlgorithm.forName(algorithm);
ASN1OctetString encryptedInfoOctedString = signedInfo.getEncryptedDigest();
String signatureValue = Hex.toHexString(encryptedInfoOctedString.getOctets());
logger.info("SIGNATURE VALUE : " + signatureValue);
Cipher cipher = Cipher.getInstance(encryptionAlgorithm.getName());
cipher.init(Cipher.DECRYPT_MODE, signerCertificate);
byte[] decrypted = cipher.doFinal(encryptedInfoOctedString.getOctets());
ASN1InputStream inputDecrypted = new ASN1InputStream(decrypted);
ASN1Sequence seqDecrypt = (ASN1Sequence) inputDecrypted.readObject();
logger.info("DECRYPTED : " + seqDecrypt);
DigestInfo digestInfo = new DigestInfo(seqDecrypt);
assertEquals(oidDigestAlgo, digestInfo.getAlgorithmId().getAlgorithm());
String decryptedDigestEncodeBase64 = Base64.encode(digestInfo.getDigest());
logger.info("DECRYPTED BASE64 : " + decryptedDigestEncodeBase64);
byte[] encoded = authenticatedAttributeSet.getEncoded();
byte[] digest = DSSUtils.digest(digestAlgorithm, encoded);
String computedDigestFromSignatureEncodeBase64 = Base64.encode(digest);
logger.info(
"COMPUTED DIGEST FROM SIGNATURE BASE64 : " + computedDigestFromSignatureEncodeBase64);
assertEquals(decryptedDigestEncodeBase64, computedDigestFromSignatureEncodeBase64);
IOUtils.closeQuietly(inputDecrypted);
IOUtils.closeQuietly(asn1sInput);
}
IOUtils.closeQuietly(inputStream);
document.close();
} catch (Exception e) {
logger.error(e.getMessage(), e);
fail(e.getMessage());
}
}