Download - Svetlin Nakov

InputStream aCertStream)
throws GeneralSecurityException {
CertificateFactory cf=CertificateFactory.getInstance(X509_CERTIFICATE_TYPE);
X509Certificate cert = (X509Certificate)cf.generateCertificate(aCertStream);
return cert;
}
/**
* Loads X.509 certificate from DER-encoded binary file (.CER file).
*/
public static X509Certificate loadX509CertificateFromCERFile(String aFileName)
throws GeneralSecurityException, IOException {
FileInputStream fis = new FileInputStream(aFileName);
X509Certificate cert = null;
try {
cert = loadX509CertificateFromStream(fis);
} finally {
fis.close();
}
return cert;
}
/**
* Loads a certification chain from given Base64-encoded string, containing
* ASN.1 DER formatted chain, stored with PkiPath encoding.
*/
public static CertPath loadCertPathFromBase64String(
String aCertChainBase64Encoded)
throws CertificateException, IOException {
byte[] certChainEncoded = Base64Utils.base64Decode(aCertChainBase64Encoded);
CertificateFactory cf=CertificateFactory.getInstance(X509_CERTIFICATE_TYPE);
InputStream certChainStream = new ByteArrayInputStream(certChainEncoded);
CertPath certPath;
try {
certPath = cf.generateCertPath(certChainStream, CERT_CHAIN_ENCODING);
} finally {
certChainStream.close();
}
return certPath;
}
/**
* Verifies given digital singature. Checks if given signature is obtained by
* signing given document with the private key corresponing to given public key.
*/
public static boolean verifyDocumentSignature(byte[] aDocument,
PublicKey aPublicKey, byte[] aSignature)
throws GeneralSecurityException {
Signature signatureAlgorithm =
Signature.getInstance(DIGITAL_SIGNATURE_ALGORITHM_NAME);
signatureAlgorithm.initVerify(aPublicKey);
signatureAlgorithm.update(aDocument);
boolean valid = signatureAlgorithm.verify(aSignature);
return valid;
}
/**
* Verifies given digital singature. Checks if given signature is obtained
* by signing given document with the private key corresponing to given
* certificate.
*/
public static boolean verifyDocumentSignature(byte[] aDocument,
X509Certificate aCertificate, byte[] aSignature)
throws GeneralSecurityException {
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