I am using bcmail-jdk16-1.46.jar and bcprov-jdk16-1.46.jar (Bouncycastle libraries) to sign a string and then verify the signature.
This is my code to sign a string:
package my.package; import java.io.FileInputStream; import java.security.Key; import java.security.KeyStore; import java.security.PrivateKey; import java.security.Security; import java.security.Signature; import java.security.cert.X509Certificate; import java.util.ArrayList; import java.util.List; import org.bouncycastle.cert.jcajce.JcaCertStore; import org.bouncycastle.cms.CMSProcessableByteArray; import org.bouncycastle.cms.CMSSignedData; import org.bouncycastle.cms.CMSSignedDataGenerator; import org.bouncycastle.cms.CMSTypedData; import org.bouncycastle.cms.jcajce.JcaSignerInfoGeneratorBuilder; import org.bouncycastle.jce.provider.BouncyCastleProvider; import org.bouncycastle.operator.ContentSigner; import org.bouncycastle.operator.jcajce.JcaContentSignerBuilder; import org.bouncycastle.operator.jcajce.JcaDigestCalculatorProviderBuilder; import org.bouncycastle.util.Store; import sun.misc.BASE64Encoder; public class SignMessage { static final String KEYSTORE_FILE = "keys/certificates.p12"; static final String KEYSTORE_INSTANCE = "PKCS12"; static final String KEYSTORE_PWD = "test"; static final String KEYSTORE_ALIAS = "Key1"; public static void main(String[] args) throws Exception { String text = "This is a message"; Security.addProvider(new BouncyCastleProvider()); KeyStore ks = KeyStore.getInstance(KEYSTORE_INSTANCE); ks.load(new FileInputStream(KEYSTORE_FILE), KEYSTORE_PWD.toCharArray()); Key key = ks.getKey(KEYSTORE_ALIAS, KEYSTORE_PWD.toCharArray()); //Sign PrivateKey privKey = (PrivateKey) key; Signature signature = Signature.getInstance("SHA1WithRSA", "BC"); signature.initSign(privKey); signature.update(text.getBytes()); //Build CMS X509Certificate cert = (X509Certificate) ks.getCertificate(KEYSTORE_ALIAS); List certList = new ArrayList(); CMSTypedData msg = new CMSProcessableByteArray(signature.sign()); certList.add(cert); Store certs = new JcaCertStore(certList); CMSSignedDataGenerator gen = new CMSSignedDataGenerator(); ContentSigner sha1Signer = new JcaContentSignerBuilder("SHA1withRSA").setProvider("BC").build(privKey); gen.addSignerInfoGenerator(new JcaSignerInfoGeneratorBuilder(new JcaDigestCalculatorProviderBuilder().setProvider("BC").build()).build(sha1Signer, cert)); gen.addCertificates(certs); CMSSignedData sigData = gen.generate(msg, false); BASE64Encoder encoder = new BASE64Encoder(); String signedContent = encoder.encode((byte[]) sigData.getSignedContent().getContent()); System.out.println("Signed content: " + signedContent + "\n"); String envelopedData = encoder.encode(sigData.getEncoded()); System.out.println("Enveloped data: " + envelopedData); } } Now, the EnvelopedData output will be used in the process to verify the signature by this way:
package my.package; import java.security.Security; import java.security.cert.X509Certificate; import java.util.Collection; import java.util.Iterator; import org.bouncycastle.cert.X509CertificateHolder; import org.bouncycastle.cert.jcajce.JcaX509CertificateConverter; import org.bouncycastle.cms.CMSSignedData; import org.bouncycastle.cms.SignerInformation; import org.bouncycastle.cms.SignerInformationStore; import org.bouncycastle.cms.jcajce.JcaSimpleSignerInfoVerifierBuilder; import org.bouncycastle.jce.provider.BouncyCastleProvider; import org.bouncycastle.util.Store; import org.bouncycastle.util.encoders.Base64; public class VerifySignature { public static void main(String[] args) throws Exception { String envelopedData = "MIAGCSqGSIb3DQEHAqCAMIACAQExCzAJBgUrDgMCGgUAMIAGCSqGSIb3DQEHAQAAoIAwggLQMIIC" + "OQIEQ479uzANBgkqhkiG9w0BAQUFADCBrjEmMCQGCSqGSIb3DQEJARYXcm9zZXR0YW5ldEBtZW5k" + "ZWxzb24uZGUxCzAJBgNVBAYTAkRFMQ8wDQYDVQQIEwZCZXJsaW4xDzANBgNVBAcTBkJlcmxpbjEi" + "MCAGA1UEChMZbWVuZGVsc29uLWUtY29tbWVyY2UgR21iSDEiMCAGA1UECxMZbWVuZGVsc29uLWUt" + "Y29tbWVyY2UgR21iSDENMAsGA1UEAxMEbWVuZDAeFw0wNTEyMDExMzQyMTlaFw0xOTA4MTAxMzQy" + "MTlaMIGuMSYwJAYJKoZIhvcNAQkBFhdyb3NldHRhbmV0QG1lbmRlbHNvbi5kZTELMAkGA1UEBhMC" + "REUxDzANBgNVBAgTBkJlcmxpbjEPMA0GA1UEBxMGQmVybGluMSIwIAYDVQQKExltZW5kZWxzb24t" + "ZS1jb21tZXJjZSBHbWJIMSIwIAYDVQQLExltZW5kZWxzb24tZS1jb21tZXJjZSBHbWJIMQ0wCwYD" + "VQQDEwRtZW5kMIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC+X1g6JvbdwJI6mQMNT41GcycH" + "UbwCFWKJ4qHDaHffz3n4h+uQJJoQvc8yLTCfnl109GB0yL2Y5YQtTohOS9IwyyMWBhh77WJtCN8r" + "dOfD2DW17877te+NlpugRvg6eOH6np9Vn3RZODVxxTyyJ8pI8VMnn13YeyMMw7VVaEO5hQIDAQAB" + "MA0GCSqGSIb3DQEBBQUAA4GBALwOIc/rWMAANdEh/GgO/DSkVMwxM5UBr3TkYbLU/5jg0Lwj3Y++" + "KhumYSrxnYewSLqK+JXA4Os9NJ+b3eZRZnnYQ9eKeUZgdE/QP9XE04y8WL6ZHLB4sDnmsgVaTU+p" + "0lFyH0Te9NyPBG0J88109CXKdXCTSN5gq0S1CfYn0staAAAxggG9MIIBuQIBATCBtzCBrjEmMCQG" + "CSqGSIb3DQEJARYXcm9zZXR0YW5ldEBtZW5kZWxzb24uZGUxCzAJBgNVBAYTAkRFMQ8wDQYDVQQI" + "EwZCZXJsaW4xDzANBgNVBAcTBkJlcmxpbjEiMCAGA1UEChMZbWVuZGVsc29uLWUtY29tbWVyY2Ug" + "R21iSDEiMCAGA1UECxMZbWVuZGVsc29uLWUtY29tbWVyY2UgR21iSDENMAsGA1UEAxMEbWVuZAIE" + "Q479uzAJBgUrDgMCGgUAoF0wGAYJKoZIhvcNAQkDMQsGCSqGSIb3DQEHATAcBgkqhkiG9w0BCQUx" + "DxcNMTMwNTIxMDE1MDUzWjAjBgkqhkiG9w0BCQQxFgQU8mE6gw6iudxLUc9379lWK0lUSWcwDQYJ" + "KoZIhvcNAQEBBQAEgYB5mVhqJu1iX9nUqfqk7hTYJb1lR/hQiCaxruEuInkuVTglYuyzivZjAR54" + "zx7Cfm5lkcRyyxQ35ztqoq/V5JzBa+dYkisKcHGptJX3CbmmDIa1s65mEye4eLS4MTBvXCNCUTb9" + "STYSWvr4VPenN80mbpqSS6JpVxjM0gF3QTAhHwAAAAAAAA=="; Security.addProvider(new BouncyCastleProvider()); CMSSignedData cms = new CMSSignedData(Base64.decode(envelopedData.getBytes())); Store store = cms.getCertificates(); SignerInformationStore signers = cms.getSignerInfos(); Collection c = signers.getSigners(); Iterator it = c.iterator(); while (it.hasNext()) { SignerInformation signer = (SignerInformation) it.next(); Collection certCollection = store.getMatches(signer.getSID()); Iterator certIt = certCollection.iterator(); X509CertificateHolder certHolder = (X509CertificateHolder) certIt.next(); X509Certificate cert = new JcaX509CertificateConverter().setProvider("BC").getCertificate(certHolder); if (signer.verify(new JcaSimpleSignerInfoVerifierBuilder().setProvider("BC").build(cert))) { System.out.println("verified"); } } } } Everything works good until signer.verify(..) due to the following Exception:
Exception in thread "main" org.bouncycastle.cms.CMSSignerDigestMismatchException: message-digest attribute value does not match calculated value at org.bouncycastle.cms.SignerInformation.doVerify(Unknown Source) at org.bouncycastle.cms.SignerInformation.verify(Unknown Source) at my.package.VerifySignature.main(VerifySignature.java:64) And I really don't know what I am doing wrong. Can someone please give me a hint of what is happening?
PS. If someone wants to test the above code, you will need the test certificate file I am using to replicate all this, just download/save it from here:
https://dl.dropboxusercontent.com/u/15208254/keys/certificates.p12