Develop Reference

PGP Encrypt using BouncyCastle in Java

I was given a task to build a java method to encrypt data (String or InputStream) using PGP. I have generated a test public key, private key with passphrase following the guide here. I then exported the public key using the command below and copy and pasted it to my java code.
gpg --armor --output pubkey.txt --export 'Your Name'
I am able to encrypt a file using the command below
gpg --encrypt --armor -r 'Your Name' plaintext.txt
And I get the below content which is what I'm trying to achieve in my java program. I might need to sign it later as part of the requirement but all I want to do for now is to be able to successfully encrypt it like this.
-----BEGIN PGP MESSAGE-----
Version: GnuPG v2.0.22 (GNU/Linux)
hQEMA0PxXau0Q30VAQf/RuWsN3f4L2HW2GJWOZUjetJsw0odXYbDc7Sug1gZULP8
I0KRrvxnHgiiJgSlBZsws8E8iB1/LDCYJ8oJGj6olicz83iUT8VLdzdJZlc0+96/
BHAvtSTtEv2PWZlh307nU+Zn9cuGAccaijyekCosS5/0JpDyXSFefsLTexMgphAL
veXsxtsISyUU6S0xUux6Ac9HgUWTpCrlNaSdqBN1bk7y8YuvbZgbQ5akwY5FEbq1
f9rxmgXgEgz3N+7f8n5yN2OvWiEyXb+qngVgDLzysD8NTtKDqtw5nViscvVF1h3v
AebdxYxOKGYnWk6XAWhpIgIZdY0ZXG0yu9NJH5VfLtJSAc3c6d2/Nhb7g+k+f2Mn
srZW6XzHCeyGQQqSfr5YJfyUVdsW12udmhnc+ErbRkz84oDkMvFaxes6+2AAKrP/
jdWXsp4fTPl454m+tG5ec/Kn0Q==
=cZH2
-----END PGP MESSAGE-----
The java method I need to build accepts a Public Key as a String parameter where I then use the following method to convert it to a PGPPublicKey.
private static PGPPublicKey getPublicKey(String keyAscii) throws IOException, PGPException, Exception {
InputStream encodedKey = new ByteArrayInputStream(keyAscii.getBytes());
InputStream decodedKey = PGPUtil.getDecoderStream(encodedKey);
JcaPGPPublicKeyRingCollection pgpPub = new JcaPGPPublicKeyRingCollection(decodedKey);
decodedKey.close();
PGPPublicKey key = null;
Iterator<PGPPublicKeyRing> rIt = pgpPub.getKeyRings();
while (key == null && rIt.hasNext()) {
PGPPublicKeyRing kRing = rIt.next();
Iterator<PGPPublicKey> kIt = kRing.getPublicKeys();
while (key == null && kIt.hasNext()) {
PGPPublicKey k = kIt.next();
if (k.isEncryptionKey()) {
key = k;
}
}
}
if (key == null) {
throw new Exception("Can't find key");
}
return key;
}
However, when I run the java program, I get an error "exception constructing public key" on the following line of code.
OutputStream cOut = encGen.open(encOut, new byte[4096]);
Complete error below
org.bouncycastle.openpgp.PGPException: exception constructing public key
at org.bouncycastle.openpgp.operator.jcajce.JcaPGPKeyConverter.getPublicKey(Unknown Source)
at org.bouncycastle.openpgp.operator.jcajce.JcePublicKeyKeyEncryptionMethodGenerator.encryptSessionInfo(Unknown Source)
at org.bouncycastle.openpgp.operator.PublicKeyKeyEncryptionMethodGenerator.generate(Unknown Source)
at org.bouncycastle.openpgp.PGPEncryptedDataGenerator.open(Unknown Source)
at org.bouncycastle.openpgp.PGPEncryptedDataGenerator.open(Unknown Source)
at pgp.PgpImpl.encrypt(PgpImpl.java:84)
at pgp.PgpImpl.main(PgpImpl.java:216)
Caused by: java.security.NoSuchProviderException: no such provider: BC
at sun.security.jca.GetInstance.getService(GetInstance.java:83)
at sun.security.jca.GetInstance.getInstance(GetInstance.java:206)
at java.security.KeyFactory.getInstance(KeyFactory.java:211)
at org.bouncycastle.jcajce.util.NamedJcaJceHelper.createKeyFactory(Unknown Source)
at org.bouncycastle.openpgp.operator.jcajce.OperatorHelper.createKeyFactory(Unknown Source)
at org.bouncycastle.openpgp.operator.jcajce.JcaPGPKeyConverter.implGeneratePublic(Unknown Source)
... 7 more
I followed the sample here but it didn't provide any information on how to construct the publickey coming from a String.
Here's my code so far.
package pgp;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.SecureRandom;
import java.util.Date;
import java.util.Iterator;
import org.bouncycastle.bcpg.SymmetricKeyAlgorithmTags;
import org.bouncycastle.openpgp.PGPEncryptedDataGenerator;
import org.bouncycastle.openpgp.PGPException;
import org.bouncycastle.openpgp.PGPLiteralData;
import org.bouncycastle.openpgp.PGPLiteralDataGenerator;
import org.bouncycastle.openpgp.PGPPrivateKey;
import org.bouncycastle.openpgp.PGPPublicKey;
import org.bouncycastle.openpgp.PGPPublicKeyRing;
import org.bouncycastle.openpgp.PGPPublicKeyRingCollection;
import org.bouncycastle.openpgp.PGPSecretKey;
import org.bouncycastle.openpgp.PGPUtil;
import org.bouncycastle.openpgp.operator.KeyFingerPrintCalculator;
import org.bouncycastle.openpgp.operator.PGPDataEncryptorBuilder;
import org.bouncycastle.openpgp.operator.PGPKeyEncryptionMethodGenerator;
import org.bouncycastle.openpgp.operator.jcajce.JcaKeyFingerprintCalculator;
import org.bouncycastle.openpgp.operator.jcajce.JcePBESecretKeyDecryptorBuilder;
import org.bouncycastle.openpgp.operator.jcajce.JcePGPDataEncryptorBuilder;
import org.bouncycastle.openpgp.operator.jcajce.JcePublicKeyKeyEncryptionMethodGenerator;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.bouncycastle.openpgp.PGPSecretKeyRing;
import org.bouncycastle.openpgp.PGPSecretKeyRingCollection;
import org.bouncycastle.openpgp.jcajce.JcaPGPPublicKeyRingCollection;
public class PgpImpl {
public PgpImpl() {
}
private static String encrypt(byte[] data, PGPPublicKey encryptionKey) throws Exception {
String step = "Step-0";
try {
step = "Step-1";
PGPEncryptedDataGenerator encGen = new PGPEncryptedDataGenerator(
new JcePGPDataEncryptorBuilder(SymmetricKeyAlgorithmTags.AES_256)
.setWithIntegrityPacket(true)
.setSecureRandom(new SecureRandom())
.setProvider("BC"));
step = "Step-2";
encGen.addMethod(new JcePublicKeyKeyEncryptionMethodGenerator(encryptionKey)
.setSecureRandom(new SecureRandom()).setProvider("BC"));
step = "Step-3";
ByteArrayOutputStream encOut = new ByteArrayOutputStream();
step = "Step-4";
// create an indefinite length encrypted stream
OutputStream cOut = encGen.open(encOut, new byte[4096]);
step = "Step-5";
// write out the literal data
PGPLiteralDataGenerator lData = new PGPLiteralDataGenerator();
OutputStream pOut = lData.open(cOut, PGPLiteralData.BINARY, PGPLiteralData.CONSOLE, data.length,
new Date());
pOut.write(data);
pOut.close();
// finish the encryption
cOut.close();
step = "Step-6";
return new String(encOut.toByteArray());
} catch (Exception e) {
//throw new Exception(String.format("%s: %s", e.getMessage(), step));
e.printStackTrace();
}
return new String(step);
}
private static PGPPublicKey getPublicKey(String keyAscii) throws IOException, PGPException, Exception {
InputStream encodedKey = new ByteArrayInputStream(keyAscii.getBytes());
InputStream decodedKey = PGPUtil.getDecoderStream(encodedKey);
JcaPGPPublicKeyRingCollection pgpPub = new JcaPGPPublicKeyRingCollection(decodedKey);
decodedKey.close();
PGPPublicKey key = null;
Iterator<PGPPublicKeyRing> rIt = pgpPub.getKeyRings();
while (key == null && rIt.hasNext()) {
PGPPublicKeyRing kRing = rIt.next();
Iterator<PGPPublicKey> kIt = kRing.getPublicKeys();
while (key == null && kIt.hasNext()) {
PGPPublicKey k = kIt.next();
if (k.isEncryptionKey()) {
key = k;
}
}
}
if (key == null) {
throw new Exception("Can't find key");
}
return key;
}
public static void main(String[] args) {
String publicKey = "-----BEGIN PGP PUBLIC KEY BLOCK-----\r\n" + "Version: GnuPG v2.0.22 (GNU/Linux)\r\n"
+ "\r\n" + "mQENBGA1A70BCADK8BnH6GgMbnS1TJSpJvgH+D9VIw0sN8XZWQsUmWWV9WSqhqXt\r\n"
+ "5wNC4XJDcaWtMCapaekQXV5S52T7QCxAz/E5oZzIDe+IUCHQz0WUs37S4Wnw+SZ6\r\n"
+ "QNPXOFaC4nNByRq6gvg0+wtD2Bo/3OJur3f0O0aRSHNiwfd0PdFgG0NU5vGV9PwE\r\n"
+ "xbTMpGssWexIC0MwJaYfJkxzov33CkwLaITvBTCn/J3oeX6JarMkgpurp1FAW0Jk\r\n"
+ "YzgGMOOxwuEVedwP4NtEPce+UtLv2NHHfqsW6xSxjWqsJkMdJ9afzu1jvn9M6e0j\r\n"
+ "MOTmPUCYVCioXK59It8ngN8NLtwaPgfnBwcbABEBAAG0BWFsbGVuiQE5BBMBAgAj\r\n"
+ "BQJgNQO9AhsDBwsJCAcDAgEGFQgCCQoLBBYCAwECHgECF4AACgkQxzGJxIrjAlxq\r\n"
+ "aggAgoiO82MZZMHyhZ3uLD4qTQ2vsT6+onhCr83kw0eFNM5AH0r3xlVARXHaViWC\r\n"
+ "SFutpb/34lrCTpJfLfKwdFU2bJP2SI3hAujtTg45UFklswu6GZaqQno6JKkZM4hw\r\n"
+ "ltFIXU1dMpIud7nsJ2QU46TI97n+HeD7DvOSGY/CFPnNot0YFHxXCKtHdPHk8JO3\r\n"
+ "JdOG0X90Yi9XSI1USv8HL/WjOTvhSqo7Qps2MpcUZrfNsa0H9Adk9xVYiz0nKNPY\r\n"
+ "qLQxFAiHb34vdav4e28anJ8th93SfiRn5OFK2G6R3DlhLlvn3h1dSAT6vSOrzx80\r\n"
+ "EylyMg2BIbRfp+JEgwCMf2V8X7kBDQRgNQO9AQgA3qV0wYvdH5M4XBzVwDtuGuIs\r\n"
+ "+GRcSRQqmvnt94e8ZE4Kv2w2Pf/JxPMwnPC92lVRypdOjmTZrT3R0z7g+D8mU5A9\r\n"
+ "o/CPvvSShA8Jh3z69S+hLP0nSaajsVsQlBGrI8ehI1EVJDsNh15PZrl27OK0aBb4\r\n"
+ "Fp0BYm0D2HaLnQPD4/jhTR13i1mt5E5hmBwiZiiWr/Wa1i1g1o/XaT4CApu91zgg\r\n"
+ "cmJBz9DL/C2hYC5lkp/cz5IJYp5BsvfA2lwamca33aHxFj8+Bz3+REWa8zvEqQ9U\r\n"
+ "a26RbPVjkeGChwNWLxNTuj1rNDdqB/KZO6iM02orqW86L45SKTBWYqPcpD7GeQAR\r\n"
+ "AQABiQEfBBgBAgAJBQJgNQO9AhsMAAoJEMcxicSK4wJcOLEIAMevvOk9iZ13T3yA\r\n"
+ "+ZW8mWKKE5aXy93VPKAvplP/WlW2VVGeb+6rEkFFsdN4doYIJPEIr+U7K0GDR6XX\r\n"
+ "TKLyI7BtUZPegOdjgcFWVGFnFogDnkrO+IPY+JUy1VMg8fGStThfa2dYEgd7yqpq\r\n"
+ "fZ97q5RQun1B+wyRdPDgC39roSGEwtXbRCZnuSMVNT7J9a2qnXkenvQRSoPjY7wQ\r\n"
+ "tn1wUfnHyjyS9OzfXTSHDi2A5JDRCh5L/V7Q93/P5Isv/U4QzIWudGM6AjuaoZ6i\r\n"
+ "chksRI9EchNKnSut9ebTyTkIJ80sB7Eyfp8TtORAnz8/Xf8A8aYD73r9rD4poSmo\r\n" + "FV15pP8=\r\n" + "=Yc74\r\n"
+ "-----END PGP PUBLIC KEY BLOCK-----";
try {
PGPPublicKey key = getPublicKey(publicKey);
System.out.println(encrypt("Test".getBytes(), key));
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (PGPException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
Appreciate any help.
UPDATE #1: After getting the stacktrace, I found out that the error is due to an invalid provider which I then change using
BouncyCastleProvider provider = new BouncyCastleProvider();
So I had to change all reference to the provider.
private static String encrypt(byte[] data, PGPPublicKey encryptionKey) {
BouncyCastleProvider provider = new BouncyCastleProvider();
String step = "Step-0";
try {
step = "Step-1";
PGPEncryptedDataGenerator encGen = new PGPEncryptedDataGenerator(
new JcePGPDataEncryptorBuilder(SymmetricKeyAlgorithmTags.AES_256)
.setWithIntegrityPacket(true)
.setSecureRandom(new SecureRandom())
.setProvider(provider));
step = "Step-2";
encGen.addMethod(new JcePublicKeyKeyEncryptionMethodGenerator(encryptionKey)
.setSecureRandom(new SecureRandom()).setProvider(provider));
step = "Step-3";
ByteArrayOutputStream encOut = new ByteArrayOutputStream();
step = "Step-4";
// create an indefinite length encrypted stream
OutputStream cOut = encGen.open(encOut, new byte[1 << 16]);
step = "Step-5";
// write out the literal data
PGPLiteralDataGenerator lData = new PGPLiteralDataGenerator();
OutputStream pOut = lData.open(cOut, PGPLiteralData.BINARY, PGPLiteralData.CONSOLE, data.length,
new Date());
pOut.write(data);
pOut.close();
// finish the encryption
cOut.close();
step = "Step-6";
return new String(encOut.toByteArray());
} catch (Exception e) {
//throw new Exception(String.format("%s: %s", e.getMessage(), step));
e.printStackTrace();
}
return new String("");
}
But now I'm getting a different error.
org.bouncycastle.openpgp.PGPException: Exception creating cipher
at org.bouncycastle.openpgp.PGPEncryptedDataGenerator.open(Unknown Source)
at org.bouncycastle.openpgp.PGPEncryptedDataGenerator.open(Unknown Source)
at pgp.PgpImpl.encrypt(PgpImpl.java:85)
at pgp.PgpImpl.main(PgpImpl.java:217)
Caused by: org.bouncycastle.openpgp.PGPException: invalid key: Illegal key size
at org.bouncycastle.openpgp.operator.jcajce.JcePGPDataEncryptorBuilder$MyPGPDataEncryptor.<init>(Unknown Source)
at org.bouncycastle.openpgp.operator.jcajce.JcePGPDataEncryptorBuilder.build(Unknown Source)
... 4 more
Caused by: java.security.InvalidKeyException: Illegal key size
at javax.crypto.Cipher.checkCryptoPerm(Cipher.java:1034)
at javax.crypto.Cipher.init(Cipher.java:1367)
at javax.crypto.Cipher.init(Cipher.java:1301)
... 6 more
UPDATE#2: Did a bit of research and came across this. Followed the instructions there and got everything working.

Your modified code works for me: (I have taken out the exception handling, but that should make no difference)
package pgp;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.SecureRandom;
import java.util.Date;
import java.util.Iterator;
import org.bouncycastle.bcpg.SymmetricKeyAlgorithmTags;
import org.bouncycastle.openpgp.PGPEncryptedDataGenerator;
import org.bouncycastle.openpgp.PGPException;
import org.bouncycastle.openpgp.PGPLiteralData;
import org.bouncycastle.openpgp.PGPLiteralDataGenerator;
import org.bouncycastle.openpgp.PGPPrivateKey;
import org.bouncycastle.openpgp.PGPPublicKey;
import org.bouncycastle.openpgp.PGPPublicKeyRing;
import org.bouncycastle.openpgp.PGPPublicKeyRingCollection;
import org.bouncycastle.openpgp.PGPSecretKey;
import org.bouncycastle.openpgp.PGPUtil;
import org.bouncycastle.openpgp.operator.KeyFingerPrintCalculator;
import org.bouncycastle.openpgp.operator.PGPDataEncryptorBuilder;
import org.bouncycastle.openpgp.operator.PGPKeyEncryptionMethodGenerator;
import org.bouncycastle.openpgp.operator.jcajce.JcaKeyFingerprintCalculator;
import org.bouncycastle.openpgp.operator.jcajce.JcePBESecretKeyDecryptorBuilder;
import org.bouncycastle.openpgp.operator.jcajce.JcePGPDataEncryptorBuilder;
import org.bouncycastle.openpgp.operator.jcajce.JcePublicKeyKeyEncryptionMethodGenerator;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.bouncycastle.openpgp.PGPSecretKeyRing;
import org.bouncycastle.openpgp.PGPSecretKeyRingCollection;
import org.bouncycastle.openpgp.jcajce.JcaPGPPublicKeyRingCollection;
public class PgpImpl {
public PgpImpl() {
}
private static String encrypt(byte[] data, PGPPublicKey encryptionKey) throws PGPException, IOException {
BouncyCastleProvider provider = new BouncyCastleProvider();
String step = "Step-0";
step = "Step-1";
PGPEncryptedDataGenerator encGen = new PGPEncryptedDataGenerator(
new JcePGPDataEncryptorBuilder(SymmetricKeyAlgorithmTags.AES_256)
.setWithIntegrityPacket(true)
.setSecureRandom(new SecureRandom())
.setProvider(provider));
step = "Step-2";
encGen.addMethod(new JcePublicKeyKeyEncryptionMethodGenerator(encryptionKey)
.setSecureRandom(new SecureRandom()).setProvider(provider));
step = "Step-3";
ByteArrayOutputStream encOut = new ByteArrayOutputStream();
step = "Step-4";
// create an indefinite length encrypted stream
OutputStream cOut = encGen.open(encOut, new byte[1 << 16]);
step = "Step-5";
// write out the literal data
PGPLiteralDataGenerator lData = new PGPLiteralDataGenerator();
OutputStream pOut = lData.open(cOut, PGPLiteralData.BINARY, PGPLiteralData.CONSOLE, data.length,
new Date());
pOut.write(data);
pOut.close();
// finish the encryption
cOut.close();
step = "Step-6";
return new String(encOut.toByteArray());
}
private static PGPPublicKey getPublicKey(String keyAscii) throws IOException, PGPException, Exception {
InputStream encodedKey = new ByteArrayInputStream(keyAscii.getBytes());
InputStream decodedKey = PGPUtil.getDecoderStream(encodedKey);
JcaPGPPublicKeyRingCollection pgpPub = new JcaPGPPublicKeyRingCollection(decodedKey);
decodedKey.close();
PGPPublicKey key = null;
Iterator<PGPPublicKeyRing> rIt = pgpPub.getKeyRings();
while (key == null && rIt.hasNext()) {
PGPPublicKeyRing kRing = rIt.next();
Iterator<PGPPublicKey> kIt = kRing.getPublicKeys();
while (key == null && kIt.hasNext()) {
PGPPublicKey k = kIt.next();
if (k.isEncryptionKey()) {
key = k;
}
}
}
if (key == null) {
throw new Exception("Can't find key");
}
return key;
}
public static void main(String[] args) throws Exception {
String publicKey = "-----BEGIN PGP PUBLIC KEY BLOCK-----\r\n" + "Version: GnuPG v2.0.22 (GNU/Linux)\r\n"
+ "\r\n" + "mQENBGA1A70BCADK8BnH6GgMbnS1TJSpJvgH+D9VIw0sN8XZWQsUmWWV9WSqhqXt\r\n"
+ "5wNC4XJDcaWtMCapaekQXV5S52T7QCxAz/E5oZzIDe+IUCHQz0WUs37S4Wnw+SZ6\r\n"
+ "QNPXOFaC4nNByRq6gvg0+wtD2Bo/3OJur3f0O0aRSHNiwfd0PdFgG0NU5vGV9PwE\r\n"
+ "xbTMpGssWexIC0MwJaYfJkxzov33CkwLaITvBTCn/J3oeX6JarMkgpurp1FAW0Jk\r\n"
+ "YzgGMOOxwuEVedwP4NtEPce+UtLv2NHHfqsW6xSxjWqsJkMdJ9afzu1jvn9M6e0j\r\n"
+ "MOTmPUCYVCioXK59It8ngN8NLtwaPgfnBwcbABEBAAG0BWFsbGVuiQE5BBMBAgAj\r\n"
+ "BQJgNQO9AhsDBwsJCAcDAgEGFQgCCQoLBBYCAwECHgECF4AACgkQxzGJxIrjAlxq\r\n"
+ "aggAgoiO82MZZMHyhZ3uLD4qTQ2vsT6+onhCr83kw0eFNM5AH0r3xlVARXHaViWC\r\n"
+ "SFutpb/34lrCTpJfLfKwdFU2bJP2SI3hAujtTg45UFklswu6GZaqQno6JKkZM4hw\r\n"
+ "ltFIXU1dMpIud7nsJ2QU46TI97n+HeD7DvOSGY/CFPnNot0YFHxXCKtHdPHk8JO3\r\n"
+ "JdOG0X90Yi9XSI1USv8HL/WjOTvhSqo7Qps2MpcUZrfNsa0H9Adk9xVYiz0nKNPY\r\n"
+ "qLQxFAiHb34vdav4e28anJ8th93SfiRn5OFK2G6R3DlhLlvn3h1dSAT6vSOrzx80\r\n"
+ "EylyMg2BIbRfp+JEgwCMf2V8X7kBDQRgNQO9AQgA3qV0wYvdH5M4XBzVwDtuGuIs\r\n"
+ "+GRcSRQqmvnt94e8ZE4Kv2w2Pf/JxPMwnPC92lVRypdOjmTZrT3R0z7g+D8mU5A9\r\n"
+ "o/CPvvSShA8Jh3z69S+hLP0nSaajsVsQlBGrI8ehI1EVJDsNh15PZrl27OK0aBb4\r\n"
+ "Fp0BYm0D2HaLnQPD4/jhTR13i1mt5E5hmBwiZiiWr/Wa1i1g1o/XaT4CApu91zgg\r\n"
+ "cmJBz9DL/C2hYC5lkp/cz5IJYp5BsvfA2lwamca33aHxFj8+Bz3+REWa8zvEqQ9U\r\n"
+ "a26RbPVjkeGChwNWLxNTuj1rNDdqB/KZO6iM02orqW86L45SKTBWYqPcpD7GeQAR\r\n"
+ "AQABiQEfBBgBAgAJBQJgNQO9AhsMAAoJEMcxicSK4wJcOLEIAMevvOk9iZ13T3yA\r\n"
+ "+ZW8mWKKE5aXy93VPKAvplP/WlW2VVGeb+6rEkFFsdN4doYIJPEIr+U7K0GDR6XX\r\n"
+ "TKLyI7BtUZPegOdjgcFWVGFnFogDnkrO+IPY+JUy1VMg8fGStThfa2dYEgd7yqpq\r\n"
+ "fZ97q5RQun1B+wyRdPDgC39roSGEwtXbRCZnuSMVNT7J9a2qnXkenvQRSoPjY7wQ\r\n"
+ "tn1wUfnHyjyS9OzfXTSHDi2A5JDRCh5L/V7Q93/P5Isv/U4QzIWudGM6AjuaoZ6i\r\n"
+ "chksRI9EchNKnSut9ebTyTkIJ80sB7Eyfp8TtORAnz8/Xf8A8aYD73r9rD4poSmo\r\n" + "FV15pP8=\r\n" +
"=Yc74\r\n"
+ "-----END PGP PUBLIC KEY BLOCK-----";
PGPPublicKey key = getPublicKey(publicKey);
System.out.println(encrypt("Test".getBytes(), key));
}
}
My pom.xml has:
<dependency>
<groupId>org.bouncycastle</groupId>
<artifactId>bcpg-jdk15on</artifactId>
<version>1.68</version>
</dependency>
<dependency>
<groupId>org.bouncycastle</groupId>
<artifactId>bcprov-jdk15on</artifactId>
<version>1.68</version>
</dependency>
Can you run that code and see what happens locally?

How to add digital signature to Excel and JPG files?

I am using below code to generate and add digital signatures to the Excel file:
SignedObject signedHashObject =null;
signatureConfig.setKey((PrivateKey) privateKey);signatureConfig.setSigningCertificateChain(Collections.singletonList(Util.getX509Certificate(certificateAlias)));
OPCPackage pkg = OPCPackage.open(selectedFileName, PackageAccess.READ_WRITE);
signatureConfig.setOpcPackage(pkg);
SignatureInfo si = new SignatureInfo();
si.setSignatureConfig(signatureConfig);
si.confirmSignature();
pkg.close();
Here the private key is java.security.mscapi.rsaprivatekey.
After fixing all the version compatibility issues, I am stuck with the below error,
The specified key of type sun.security.mscapi.RSAPrivateKey is not an RSAPrivateKey

I've fixed this now via #62159.
Make sure to set -Dorg.apache.xml.security.ignoreLineBreaks=true in the JVM properties.
Complete example, i.e. my test code:
import java.awt.geom.Rectangle2D;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.security.KeyStore;
import java.security.PrivateKey;
import java.security.cert.X509Certificate;
import java.util.Calendar;
import java.util.Collections;
import java.util.List;
import java.util.TimeZone;
import org.apache.poi.openxml4j.opc.OPCPackage;
import org.apache.poi.openxml4j.opc.PackageAccess;
import org.apache.poi.poifs.crypt.HashAlgorithm;
import org.apache.poi.poifs.crypt.dsig.SignatureConfig;
import org.apache.poi.poifs.crypt.dsig.SignatureInfo;
import org.apache.poi.util.IOUtils;
import org.apache.poi.xslf.usermodel.XMLSlideShow;
import org.apache.poi.xslf.usermodel.XSLFTextBox;
public class CertTest {
static PrivateKey winKey;
static List<X509Certificate> winChain;
public static void main(String[] args) throws Exception {
System.setProperty("org.apache.xml.security.ignoreLineBreaks", "true");
HashAlgorithm hashes[] = { HashAlgorithm.sha1, HashAlgorithm.sha256, HashAlgorithm.sha384, HashAlgorithm.sha512 };
loadWinKey();
SignatureConfig signatureConfig = new SignatureConfig();
Calendar cal = Calendar.getInstance();
cal.clear();
cal.set(2018, 1, 18, 12, 0, 0);
signatureConfig.setExecutionTime(cal.getTime());
for (final HashAlgorithm ha : hashes) {
try (final OPCPackage pkg = loadOPC("test-" + ha + ".pptx")) {
signatureConfig.setDigestAlgo(ha);
signatureConfig.setKey(winKey);
signatureConfig.setSigningCertificateChain(winChain);
signatureConfig.setOpcPackage(pkg);
SignatureInfo si = new SignatureInfo();
si.setSignatureConfig(signatureConfig);
si.confirmSignature();
}
}
}
static void loadWinKey() throws Exception {
String alias = "poitest";
KeyStore keystore = KeyStore.getInstance("Windows-MY", "SunMSCAPI");
keystore.load(null, null);
winKey = (PrivateKey) keystore.getKey(alias, null);
winChain = Collections.singletonList((X509Certificate) keystore.getCertificate(alias));
}
static OPCPackage loadOPC(String fileName) throws Exception {
try (final XMLSlideShow ppt = new XMLSlideShow()) {
try (final FileOutputStream fos = new FileOutputStream(fileName)) {
XSLFTextBox tb = ppt.createSlide().createTextBox();
tb.setText("test");
tb.setAnchor(new Rectangle2D.Double(100, 100, 100, 100));
ppt.write(fos);
}
return OPCPackage.open(fileName, PackageAccess.READ_WRITE);
}
}
}

Problems with Java xml-dsig and namespaces

I have been trying to get XML signing to work, using the JDK's javax.xml.crypto.dsig package.
It works when i don't have any namespaces, but as soon as i add the namespaces, then the signing and validation works, on the in-memory DOM object. As soon as the object is transformed and then parsed again, the validation fails.
I have created an example where this can easily be seen. In the main-method, right after creating the Document, i have to transform and then parse the document, in which case signing and validation works. This seems to be just really stupid =))
So my question: Does anyone have an idea how i can fix the code so i don't need to first transform the Document to bytes then parse them again, so that the signature validation works?
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
import java.security.KeyStore;
import java.security.KeyStore.PrivateKeyEntry;
import java.security.PublicKey;
import java.security.cert.X509Certificate;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.TimeZone;
import java.util.UUID;
import javax.xml.crypto.dsig.CanonicalizationMethod;
import javax.xml.crypto.dsig.DigestMethod;
import javax.xml.crypto.dsig.Reference;
import javax.xml.crypto.dsig.SignatureMethod;
import javax.xml.crypto.dsig.SignedInfo;
import javax.xml.crypto.dsig.Transform;
import javax.xml.crypto.dsig.XMLSignature;
import javax.xml.crypto.dsig.XMLSignatureFactory;
import javax.xml.crypto.dsig.dom.DOMSignContext;
import javax.xml.crypto.dsig.dom.DOMValidateContext;
import javax.xml.crypto.dsig.keyinfo.KeyInfo;
import javax.xml.crypto.dsig.keyinfo.KeyInfoFactory;
import javax.xml.crypto.dsig.keyinfo.X509Data;
import javax.xml.crypto.dsig.spec.C14NMethodParameterSpec;
import javax.xml.crypto.dsig.spec.TransformParameterSpec;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
public class Test {
public static void main(String[] args) throws Exception {
System.out.println("Creating doc...");
Document doc = createDoc();
// AFTER creating the document, i must immediately
// transform and parse the document, to have xml
// signing and validation work:
doc = parse(transform(doc));
System.out.println();
System.out.println("Initial unsigned document:");
System.out.println();
dumpDocument(doc);
System.out.println();
System.out.println("Signing...");
sign(doc);
validate(doc);
System.out.println();
System.out.println("Initial signed and validated document:");
System.out.println();
dumpDocument(doc);
System.out.println();
// transform
System.out.println("Transforming...");
byte[] bytes = transform(doc);
System.out.println("Transformed document:");
System.out.println();
System.out.println(new String(bytes, "UTF-8"));
System.out.println();
// now parse
System.out.println("Parsing...");
doc = parse(bytes);
System.out.println();
System.out.println("After parsing:");
System.out.println();
//dumpDocument(doc);
System.out.println("Validating...");
validate(doc);
}
private static void dumpDocument(Node root) throws TransformerException {
Transformer transformer = TransformerFactory.newInstance().newTransformer();
transformer.transform(new DOMSource(root), new StreamResult(System.out));
}
public static byte[] transform(Document doc) throws Exception {
ByteArrayOutputStream out = new ByteArrayOutputStream();
TransformerFactory tf = TransformerFactory.newInstance();
Transformer transformer = tf.newTransformer();
transformer.transform(new DOMSource(doc), new StreamResult(out));
return out.toByteArray();
}
public static Document parse(byte[] bytes) throws Exception {
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
dbf.setNamespaceAware(true);
Document doc = dbf.newDocumentBuilder().parse(new ByteArrayInputStream(bytes));
return doc;
}
public static Document createDoc() throws Exception {
String issuer = "test";
String destination = "test";
String assertionConsumerServiceUrl = "test";
Calendar issueInstant = Calendar.getInstance();
// create dates
SimpleDateFormat simpleDf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'");
simpleDf.setTimeZone(TimeZone.getTimeZone("UTC"));
String issueInstantS = simpleDf.format(issueInstant.getTime());
String notBeforeS = issueInstantS;
issueInstant.add(Calendar.SECOND, 10);
String notOnOrAfterS = simpleDf.format(issueInstant.getTime());
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
dbf.setNamespaceAware(true);
DocumentBuilder docBuilder = dbf.newDocumentBuilder();
Document doc = docBuilder.newDocument();
Element authnReqE = doc.createElementNS("urn:oasis:names:tc:SAML:2.0:protocol", "AuthnRequest");
//Element authnReqE = doc.createElement("AuthnRequest");
authnReqE.setPrefix("samlp");
authnReqE.setAttribute("Version", "2.0");
authnReqE.setAttribute("IssueInstant", issueInstantS);
authnReqE.setAttribute("ProtocolBinding", "urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST");
authnReqE.setAttribute("AssertionConsumerServiceURL", assertionConsumerServiceUrl);
authnReqE.setAttribute("Destination", destination);
doc.appendChild(authnReqE);
Element issuerE = doc.createElementNS("urn:oasis:names:tc:SAML:2.0:assertion", "Issuer");
//Element issuerE = doc.createElement("Issuer");
issuerE.setPrefix("saml");
issuerE.setTextContent(issuer);
authnReqE.appendChild(issuerE);
Element conditionsE = doc.createElementNS("urn:oasis:names:tc:SAML:2.0:assertion", "Conditions");
//Element conditionsE = doc.createElement("Conditions");
conditionsE.setPrefix("saml");
conditionsE.setAttribute("NotBefore", notBeforeS);
conditionsE.setAttribute("NotOnOrAfter", notOnOrAfterS);
authnReqE.appendChild(conditionsE);
return doc;
}
public static void sign(Document doc) throws Exception {
String id = "Signed_" + UUID.randomUUID().toString();
Element rootElement = doc.getDocumentElement();
rootElement.setAttribute("ID", id);
// Create a DOM XMLSignatureFactory that will be used to
// generate the enveloped signature.
XMLSignatureFactory fac = XMLSignatureFactory.getInstance("DOM");
// Create a Reference to the enveloped document (in this case,
// you are signing the whole document, so a URI of "" signifies
// that, and also specify the SHA1 digest algorithm and
// the ENVELOPED Transform.
List<Transform> transforms = new ArrayList<>();
transforms.add(fac.newTransform(Transform.ENVELOPED, (TransformParameterSpec) null));
transforms.add(fac.newTransform(CanonicalizationMethod.EXCLUSIVE, (TransformParameterSpec) null));
DigestMethod digestMethod = fac.newDigestMethod(DigestMethod.SHA1, null);
Reference ref = fac.newReference("#" + id, digestMethod, transforms, null, null);
//Reference ref = fac.newReference("", digestMethod, transforms, null, null);
// Create the SignedInfo.
SignedInfo signedInfo = fac.newSignedInfo(
fac.newCanonicalizationMethod(CanonicalizationMethod.EXCLUSIVE, (C14NMethodParameterSpec) null), //
fac.newSignatureMethod(SignatureMethod.RSA_SHA1, null), //
Collections.singletonList(ref));
// Load the KeyStore and get the signing key and certificate.
KeyStore ks = KeyStore.getInstance("JKS");
ks.load(new FileInputStream("KeyStore_client.jks"), "changeit".toCharArray());
KeyStore.PrivateKeyEntry keyEntry = (KeyStore.PrivateKeyEntry) ks.getEntry(ks.aliases().nextElement(),
new KeyStore.PasswordProtection("changeit".toCharArray()));
X509Certificate cert = (X509Certificate) keyEntry.getCertificate();
// Create the KeyInfo containing the X509Data.
KeyInfoFactory kif = fac.getKeyInfoFactory();
List<Object> x509Content = new ArrayList<>();
x509Content.add(cert.getSubjectX500Principal().getName());
x509Content.add(cert);
X509Data xd = kif.newX509Data(x509Content);
KeyInfo keyInfo = kif.newKeyInfo(Collections.singletonList(xd));
// Create a DOMSignContext and specify the RSA PrivateKey and
// location of the resulting XMLSignature's parent element.
DOMSignContext dsc = new DOMSignContext(keyEntry.getPrivateKey(), rootElement);
//dsc.setDefaultNamespacePrefix("samlp");
dsc.putNamespacePrefix(XMLSignature.XMLNS, "ds");
dsc.setIdAttributeNS(rootElement, null, "ID");
// Create the XMLSignature, but don't sign it yet.
XMLSignature signature = fac.newXMLSignature(signedInfo, keyInfo);
// Marshal, generate, and sign the enveloped signature.
signature.sign(dsc);
}
public static void validate(Document doc) throws Exception {
// Create a DOM XMLSignatureFactory that will be used to
// generate the enveloped signature.
XMLSignatureFactory fac = XMLSignatureFactory.getInstance("DOM");
// Find Signature element.
NodeList nl = doc.getElementsByTagNameNS(XMLSignature.XMLNS, "Signature");
if (nl.getLength() == 0) {
throw new Exception("Cannot find Signature element!");
} else if (nl.getLength() > 1) {
throw new Exception("Found multiple Signature elements!");
}
// Load the KeyStore and get the signing key and certificate.
KeyStore ks = KeyStore.getInstance("JKS");
ks.load(new FileInputStream("KeyStore_client.jks"), "changeit".toCharArray());
KeyStore.PrivateKeyEntry entry = (PrivateKeyEntry) ks.getEntry(ks.aliases().nextElement(),
new KeyStore.PasswordProtection("changeit".toCharArray()));
PublicKey publicKey = entry.getCertificate().getPublicKey();
// Create a DOMValidateContext and specify a KeySelector
// and document context.
Node signatureNode = nl.item(0);
DOMValidateContext valContext = new DOMValidateContext(publicKey, signatureNode);
valContext.setDefaultNamespacePrefix("samlp");
valContext.putNamespacePrefix(XMLSignature.XMLNS, "ds");
valContext.putNamespacePrefix("urn:oasis:names:tc:SAML:2.0:protocol", "samlp");
valContext.putNamespacePrefix("urn:oasis:names:tc:SAML:2.0:assertion", "saml");
valContext.setIdAttributeNS(doc.getDocumentElement(), null, "ID");
// Unmarshal the XMLSignature.
valContext.setProperty("javax.xml.crypto.dsig.cacheReference", Boolean.TRUE);
XMLSignature signature = fac.unmarshalXMLSignature(valContext);
// Validate the XMLSignature.
boolean coreValidity = signature.validate(valContext);
// Check core validation status.
if (coreValidity) {
System.out.println("Signature passed core validation");
} else {
System.err.println("Signature failed core validation");
boolean sv = signature.getSignatureValue().validate(valContext);
System.out.println("signature validation status: " + sv);
if (!sv) {
// Check the validation status of each Reference.
Iterator<?> i = signature.getSignedInfo().getReferences().iterator();
for (int j = 0; i.hasNext(); j++) {
boolean refValid = ((Reference) i.next()).validate(valContext);
System.out.println("ref[" + j + "] validity status: " + refValid);
}
}
throw new RuntimeException("Uh-oh, failed!");
}
}
}

How to sign signature data using bouncy castle?

**This is my code to sign a String.</br>**
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);
FileOutputStream sigfos = new FileOutputStream("D:\\SBI-DATA\\file\\signature_1.txt");
sigfos.write(Base64.encodeBase64(sp.getEncoded()));
sigfos.close();
}
}
Now, the EnvelopedData output will be used in the process to verify the signature by this way:
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 {
File p7s = new File("D:\\SBI-DATA\\file\\signature_2.txt") ;
int size = ((int) p7s.length());
byte[] sig = new byte[size];
File f = new File("D:\\SBI-DATA\\file\\plain.txt") ;
int sizecontent = ((int) f.length());
byte[] Data_Bytes = new byte[sizecontent];
Security.addProvider(new BouncyCastleProvider());
CMSSignedData signedData = new CMSSignedData(new CMSProcessableByteArray(Data_Bytes), sig);
Store store = signedData.getCertificates();
SignerInformationStore signers = signedData.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 certFromSignedData = new JcaX509CertificateConverter().setProvider(BC_PROVIDER).getCertificate(certHolder);
if (signer.verify(new JcaSimpleSignerInfoVerifierBuilder().setProvider(BC_PROVIDER).build(certFromSignedData))) {
System.out.println("Signature verified");
} else {
System.out.println("Signature verification failed");
}
}
}
}
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?

I think you are signing it twice, once directly using Signature and the other one using ContentSigner. You need only to sign the data, not the signature.
So the solution should be to replace signature.sign() with text.getBytes(), or text.getBytes(StandardCharsets.UTF_8) if you want to explicitly define a character set for text instead of using some system default.

Correct way to sign and verify signature using bouncycastle

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:
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 fine 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)
Can someone please give me a hint of what could be happening?
PS. If someone wants to test above code you will need the test certificate file that I am using to replicate this, just download it from here:
https://www.dropbox.com/s/zs4jo1a86v8qamw/certificates.p12?dl=0

The
gen.generate(msg, false)
means the signed data is not encapsulated in the signature. This is fine if you want to create a detached signature, but it does mean that when you go to verify the SignedData you have to use the CMSSignedData constructor that takes a copy of the data as well - in this case the code is using the single argument constructor which has to assume the signed data was encapsulated (so for this case will be empty), with the result that the attempt at verification is failing.

There are two kinds of CMSSignedData object generated using CMSSignedDataGenerator They are generated by the following way:
The one below generates a CMSSignedData object carrying a detached CMS signature
gen.generate(cmsdata);
The code below creates a CMSSignedData carrying a detached CMS signature, having the data encapsulated
gen.generate(cmsdata, true);
So verifying them requires 2 approaches
Approach No.1 to verify detached signature with encapsulated data
//sig is the Signature object
CMSSignedData signedData = new CMSSignedData(Base64.decode(sig.getBytes()));
Approach No.2 to verify detached signature without encapsulated data, just the detached signature
//Create a CMSProcessable object, specify any encoding, I have used mine
CMSProcessable signedContent = new CMSProcessableByteArray(content.getBytes("ISO-8859-1"));
//Create a InputStream object
InputStream is = new ByteArrayInputStream(Base64.decode(sig.getBytes()));
//Pass them both to CMSSignedData constructor
CMSSignedData signedData = new CMSSignedData(signedContent, is);
Rest of the code for verification remains the same
Store store = signedData.getCertificates();
SignerInformationStore signers = signedData.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))) {
ret = true;
}
}

If we use signature.sign() as in the OP's answer, we won't be able to retrieve the original message, because its only the signature.
You should just input the original text bytes rather than the signed content. Basically, ignore this part:
//Sign
PrivateKey privKey = (PrivateKey) key;
Signature signature = Signature.getInstance("SHA1WithRSA", "BC");
signature.initSign(privKey);
signature.update(text.getBytes());
and just input as:
CMSTypedData msg = new CMSProcessableByteArray(text.getBytes());

You can find answer at this link here You need to just add some headers to message or just add one blank line before message then sign the message then it will work fine.

Got it working for detached signature :D
package signature;
import java.security.Provider;
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.CMSProcessable;
import org.bouncycastle.cms.CMSProcessableByteArray;
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 {
static final String DIGEST_SHA1 = "SHA1withRSA";
static final String BC_PROVIDER = "BC";
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==";
String Sig_Bytes ="YduK22AlMLSXV3ajX5r/pX5OQ0xjj58uhGT9I9MvOrz912xNHo+9OiOKeMOD+Ys2/LUW3XaN6T+/"+
"tuRM5bi4RK7yjaqaJCZWtr/O4I968BQGgt0cyNvK8u0Jagbr9MYk6G7nnejbRXYHyAOaunqD05lW"+
"U/+g92i18dl0OMc50m4=";
Provider provider = new BouncyCastleProvider();
Security.addProvider(provider);
CMSSignedData signedData = new CMSSignedData(Base64.decode(envelopedData.getBytes()));
CMSProcessable cmsProcesableContent = new CMSProcessableByteArray(Base64.decode(Sig_Bytes.getBytes()));
signedData = new CMSSignedData(cmsProcesableContent, Base64.decode(envelopedData.getBytes()));
// Verify signature
Store store = signedData.getCertificates();
SignerInformationStore signers = signedData.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 certFromSignedData = new JcaX509CertificateConverter().setProvider(BC_PROVIDER).getCertificate(certHolder);
if (signer.verify(new JcaSimpleSignerInfoVerifierBuilder().setProvider(BC_PROVIDER).build(certFromSignedData))) {
System.out.println("Signature verified");
} else {
System.out.println("Signature verification failed");
}
}
}
}