pdfpkcs7.java

iText是一个能够快速产生PDF文件的java类库。iText的java类对于那些要产生包含文本

            sig = Signature.getInstance(getDigestAlgorithm(), provider);
        sig.initVerify(signCert.getPublicKey());
    }

    /**
     * Generates a signature.
     * @param privKey the private key
     * @param certChain the certificate chain
     * @param crlList the certificate revocation list
     * @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 SecurityException on error
     * @throws InvalidKeyException on error
     * @throws NoSuchProviderException on error
     * @throws NoSuchAlgorithmException on error
     */    
    public PdfPKCS7(PrivateKey privKey, Certificate[] certChain, CRL[] crlList,
                    String hashAlgorithm, String provider, boolean hasRSAdata)
      throws SecurityException, InvalidKeyException, NoSuchProviderException,
      NoSuchAlgorithmException
    {
        this.privKey = privKey;
        
        if (hashAlgorithm.equals("MD5")) {
            digestAlgorithm = ID_MD5;
        }
        else if (hashAlgorithm.equals("MD2")) {
            digestAlgorithm = ID_MD2;
        }
        else if (hashAlgorithm.equals("SHA")) {
            digestAlgorithm = ID_SHA1;
        }
        else if (hashAlgorithm.equals("SHA1")) {
            digestAlgorithm = ID_SHA1;
        }
        else {
            throw new NoSuchAlgorithmException("Unknown Hash Algorithm "+hashAlgorithm);
        }
        
        version = signerversion = 1;
        certs = new ArrayList();
        crls = new ArrayList();
        digestalgos = new HashSet();
        digestalgos.add(digestAlgorithm);
        
        //
        // Copy in the certificates and crls used to sign the private key.
        //
        signCert = (X509Certificate)certChain[0];
        for (int i = 0;i < certChain.length;i++) {
            certs.add(certChain[i]);
        }
        
        if (crlList != null) {
            for (int i = 0;i < crlList.length;i++) {
                crls.add(crlList[i]);
            }
        }
        
        if (privKey != null) {
            //
            // Now we have private key, find out what the digestEncryptionAlgorithm is.
            //
            digestEncryptionAlgorithm = privKey.getAlgorithm();
            if (digestEncryptionAlgorithm.equals("RSA")) {
                digestEncryptionAlgorithm = ID_RSA;
            }
            else if (digestEncryptionAlgorithm.equals("DSA")) {
                digestEncryptionAlgorithm = ID_DSA;
            }
            else {
                throw new NoSuchAlgorithmException("Unknown Key Algorithm "+digestEncryptionAlgorithm);
            }
        }
        if (hasRSAdata) {
            RSAdata = new byte[0];
            if (provider == null || provider.startsWith("SunPKCS11"))
                messageDigest = MessageDigest.getInstance(getHashAlgorithm());
            else
                messageDigest = MessageDigest.getInstance(getHashAlgorithm(), provider);
        }

        if (privKey != null) {
            if (provider == null)
                sig = Signature.getInstance(getDigestAlgorithm());
            else
                sig = Signature.getInstance(getDigestAlgorithm(), provider);

            sig.initSign(privKey);
        }
    }

    /**
     * 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)
            messageDigest.update(buf, off, len);
        else
            sig.update(buf, off, len);
    }
    
    /**
     * Verify the digest.
     * @throws SignatureException on error
     * @return <CODE>true</CODE> if the signature checks out, <CODE>false</CODE> otherwise
     */
    public boolean verify() throws SignatureException {
        if (verified)
            return verifyResult;
        if (sigAttr != null) {
            sig.update(sigAttr);
            if (RSAdata != null) {
                byte msd[] = messageDigest.digest();
                messageDigest.update(msd);
            }
            verifyResult = (Arrays.equals(messageDigest.digest(), digestAttr) && sig.verify(digest));
        }
        else {
            if (RSAdata != null)
                sig.update(messageDigest.digest());
            verifyResult = sig.verify(digest);
        }
        verified = true;
        return verifyResult;
    }
    
    /**
     * Get the X.509 certificates associated with this PKCS#7 object
     * @return the X.509 certificates associated with this PKCS#7 object
     */
    public Certificate[] getCertificates() {
        return (X509Certificate[])certs.toArray(new X509Certificate[certs.size()]);
    }
    
    /**
     * 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 getCRLs() {
        return crls;
    }
    
    /**
     * 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;
    }
    
    /**
     * Get the version of the PKCS#7 object. Always 1
     * @return the version of the PKCS#7 object. Always 1
     */
    public int getVersion() {
        return version;
    }
    
    /**
     * Get the version of the PKCS#7 "SignerInfo" object. Always 1
     * @return the version of the PKCS#7 "SignerInfo" object. Always 1
     */
    public int getSigningInfoVersion() {
        return signerversion;
    }
    
    /**
     * Get the algorithm used to calculate the message digest
     * @return the algorithm used to calculate the message digest
     */
    public String getDigestAlgorithm() {
        String dea = digestEncryptionAlgorithm;
        
        if (digestEncryptionAlgorithm.equals(ID_RSA) || digestEncryptionAlgorithm.equals(ID_MD5RSA)
            || digestEncryptionAlgorithm.equals(ID_MD2RSA) || digestEncryptionAlgorithm.equals(ID_SHA1RSA)) {
            dea = "RSA";
        }
        else if (digestEncryptionAlgorithm.equals(ID_DSA)) {
            dea = "DSA";
        }
        
        return getHashAlgorithm() + "with" + dea;
    }

    /**
     * Returns the algorithm.
     * @return the digest algorithm
     */
    public String getHashAlgorithm() {
        String da = digestAlgorithm;
        
        if (digestAlgorithm.equals(ID_MD5) || digestAlgorithm.equals(ID_MD5RSA)) {
            da = "MD5";
        }
        else if (digestAlgorithm.equals(ID_MD2) || digestAlgorithm.equals(ID_MD2RSA)) {
            da = "MD2";
        }
        else if (digestAlgorithm.equals(ID_SHA1) || digestAlgorithm.equals(ID_SHA1RSA)) {
            da = "SHA1";
        }
        return da;
    }

    /**
     * Loads the default root certificates at &lt;java.home&gt;/lib/security/cacerts
     * with the default provider.
     * @return a <CODE>KeyStore</CODE>
     */    
    public static KeyStore loadCacertsKeyStore() {
        return loadCacertsKeyStore(null);
    }

    /**
     * Loads the default root certificates at &lt;java.home&gt;/lib/security/cacerts.
     * @param provider the provider or <code>null</code> for the default provider
     * @return a <CODE>KeyStore</CODE>
     */    
    public static KeyStore loadCacertsKeyStore(String provider) {
        File file = new File(System.getProperty("java.home"), "lib");
        file = new File(file, "security");
        file = new File(file, "cacerts");
        FileInputStream fin = null;
        try {
            fin = new FileInputStream(file);
            KeyStore k;
            if (provider == null)
                k = KeyStore.getInstance("JKS");
            else
                k = KeyStore.getInstance("JKS", provider);
            k.load(fin, null);
            return k;
        }
        catch (Exception e) {
            throw new ExceptionConverter(e);
        }
        finally {
            try{if (fin != null) {fin.close();}}catch(Exception ex){}
        }
    }
    
    /**
     * Verifies a single certificate.
     * @param cert the certificate to verify
     * @param crls the certificate revocation list or <CODE>null</CODE>
     * @param calendar the date or <CODE>null</CODE> for the current date
     * @return a <CODE>String</CODE> with the error description or <CODE>null</CODE>
     * if no error
     */    
    public static String verifyCertificate(X509Certificate cert, Collection crls, Calendar calendar) {
        if (calendar == null)
            calendar = new GregorianCalendar();
        if (cert.hasUnsupportedCriticalExtension())
            return "Has unsupported critical extension";
        try {
            cert.checkValidity(calendar.getTime());
        }
        catch (Exception e) {
            return e.getMessage();
        }
        if (crls != null) {
            for (Iterator it = crls.iterator(); it.hasNext();) {
                if (((CRL)it.next()).isRevoked(cert))
                    return "Certificate revoked";
            }
        }
        return null;
    }
    
    /**
     * Verifies a certificate chain against a KeyStore.
     * @param certs the certificate chain
     * @param keystore the <CODE>KeyStore</CODE>
     * @param crls the certificate revocation list or <CODE>null</CODE>
     * @param calendar the date or <CODE>null</CODE> for the current date
     * @return <CODE>null</CODE> if the certificate chain could be validade or a
     * <CODE>Object[]{cert,error}</CODE> where <CODE>cert</CODE> is the
     * failed certificate and <CODE>error</CODE> is the error message
     */    
    public static Object[] verifyCertificates(Certificate certs[], KeyStore keystore, Collection crls, Calendar calendar) {
        if (calendar == null)
            calendar = new GregorianCalendar();
        for (int k = 0; k < certs.length; ++k) {
            X509Certificate cert = (X509Certificate)certs[k];
            String err = verifyCertificate(cert, crls, calendar);
            if (err != null)
                return new Object[]{cert, err};
            try {
                for (Enumeration aliases = keystore.aliases(); aliases.hasMoreElements();) {
                    try {
                        String alias = (String)aliases.nextElement();
                        if (!keystore.isCertificateEntry(alias))
                            continue;
                        X509Certificate certStoreX509 = (X509Certificate)keystore.getCertificate(alias);
                        if (verifyCertificate(certStoreX509, crls, calendar) != null)
                            continue;
                        try {
                            cert.verify(certStoreX509.getPublicKey());
                            return null;
                        }
                        catch (Exception e) {
                            continue;
                        }
                    }
                    catch (Exception ex) {
                    }
                }
            }
            catch (Exception e) {
            }
            int j;
            for (j = 0; j < certs.length; ++j) {
                if (j == k)
                    continue;
                X509Certificate certNext = (X509Certificate)certs[j];
                try {
                    cert.verify(certNext.getPublicKey());
                    break;
                }
                catch (Exception e) {