http://stackoverflow.com/questions/3939447/how-to-encrypt-a-string-stream-with-bouncycastle-pgp-without-starting-with-a-fil
package com.common.security.pgp;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.NoSuchProviderException;
import java.security.SecureRandom;
import java.security.Security;
import java.util.Date;
import java.util.Iterator;
import org.bouncycastle.bcpg.ArmoredOutputStream;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.bouncycastle.openpgp.PGPCompressedData;
import org.bouncycastle.openpgp.PGPCompressedDataGenerator;
import org.bouncycastle.openpgp.PGPEncryptedData;
import org.bouncycastle.openpgp.PGPEncryptedDataGenerator;
import org.bouncycastle.openpgp.PGPEncryptedDataList;
import org.bouncycastle.openpgp.PGPException;
import org.bouncycastle.openpgp.PGPLiteralData;
import org.bouncycastle.openpgp.PGPLiteralDataGenerator;
import org.bouncycastle.openpgp.PGPObjectFactory;
import org.bouncycastle.openpgp.PGPPrivateKey;
import org.bouncycastle.openpgp.PGPPublicKey;
import org.bouncycastle.openpgp.PGPPublicKeyEncryptedData;
import org.bouncycastle.openpgp.PGPPublicKeyRing;
import org.bouncycastle.openpgp.PGPPublicKeyRingCollection;
import org.bouncycastle.openpgp.PGPSecretKey;
import org.bouncycastle.openpgp.PGPSecretKeyRingCollection;
import org.bouncycastle.openpgp.PGPUtil;
public class PgpEncryption {
private static PGPPrivateKey findSecretKey(
PGPSecretKeyRingCollection pgpSec, long keyID, char[] pass)
throws PGPException, NoSuchProviderException {
PGPSecretKey pgpSecKey = pgpSec.getSecretKey(keyID);
if (pgpSecKey == null) {
return null;
}
return pgpSecKey.extractPrivateKey(pass, "BC");
}
public static byte[] decrypt(byte[] encrypted, InputStream keyIn, char[] password)
throws IOException, PGPException, NoSuchProviderException {
InputStream in = new ByteArrayInputStream(encrypted);
in = PGPUtil.getDecoderStream(in);
PGPObjectFactory pgpF = new PGPObjectFactory(in);
PGPEncryptedDataList enc = null;
Object o = pgpF.nextObject();
//
// the first object might be a PGP marker packet.
//
if (o instanceof PGPEncryptedDataList) {
enc = (PGPEncryptedDataList) o;
} else {
enc = (PGPEncryptedDataList) pgpF.nextObject();
}
//
// find the secret key
//
Iterator it = enc.getEncryptedDataObjects();
PGPPrivateKey sKey = null;
PGPPublicKeyEncryptedData pbe = null;
PGPSecretKeyRingCollection pgpSec = new PGPSecretKeyRingCollection(
PGPUtil.getDecoderStream(keyIn));
while (sKey == null && it.hasNext()) {
pbe = (PGPPublicKeyEncryptedData) it.next();
sKey = findSecretKey(pgpSec, pbe.getKeyID(), password);
}
if (sKey == null) {
throw new IllegalArgumentException(
"secret key for message not found.");
}
InputStream clear = pbe.getDataStream(sKey, "BC");
PGPObjectFactory pgpFact = new PGPObjectFactory(clear);
PGPCompressedData cData = (PGPCompressedData) pgpFact.nextObject();
pgpFact = new PGPObjectFactory(cData.getDataStream());
PGPLiteralData ld = (PGPLiteralData) pgpFact.nextObject();
InputStream unc = ld.getInputStream();
ByteArrayOutputStream out = new ByteArrayOutputStream();
int ch;
while ((ch = unc.read()) >= 0) {
out.write(ch);
}
byte[] returnBytes = out.toByteArray();
out.close();
return returnBytes;
}
public static byte[] encrypt(byte[] clearData, PGPPublicKey encKey,
String fileName,boolean withIntegrityCheck, boolean armor)
throws IOException, PGPException, NoSuchProviderException {
if (fileName == null) {
fileName = PGPLiteralData.CONSOLE;
}
ByteArrayOutputStream encOut = new ByteArrayOutputStream();
OutputStream out = encOut;
if (armor) {
out = new ArmoredOutputStream(out);
}
ByteArrayOutputStream bOut = new ByteArrayOutputStream();
PGPCompressedDataGenerator comData = new PGPCompressedDataGenerator(
PGPCompressedDataGenerator.ZIP);
OutputStream cos = comData.open(bOut); // open it with the final
// destination
PGPLiteralDataGenerator lData = new PGPLiteralDataGenerator();
// we want to generate compressed data. This might be a user option
// later,
// in which case we would pass in bOut.
OutputStream pOut = lData.open(cos, // the compressed output stream
PGPLiteralData.BINARY, fileName, // "filename" to store
clearData.length, // length of clear data
new Date() // current time
);
pOut.write(clearData);
lData.close();
comData.close();
PGPEncryptedDataGenerator cPk = new PGPEncryptedDataGenerator(
PGPEncryptedData.CAST5, withIntegrityCheck, new SecureRandom(),
"BC");
cPk.addMethod(encKey);
byte[] bytes = bOut.toByteArray();
OutputStream cOut = cPk.open(out, bytes.length);
cOut.write(bytes); // obtain the actual bytes from the compressed stream
cOut.close();
out.close();
return encOut.toByteArray();
}
private static PGPPublicKey readPublicKey(InputStream in)
throws IOException, PGPException {
in = PGPUtil.getDecoderStream(in);
PGPPublicKeyRingCollection pgpPub = new PGPPublicKeyRingCollection(in);
//
// we just loop through the collection till we find a key suitable for
// encryption, in the real
// world you would probably want to be a bit smarter about this.
//
//
// iterate through the key rings.
//
Iterator rIt = pgpPub.getKeyRings();
while (rIt.hasNext()) {
PGPPublicKeyRing kRing = (PGPPublicKeyRing) rIt.next();
Iterator kIt = kRing.getPublicKeys();
while (kIt.hasNext()) {
PGPPublicKey k = (PGPPublicKey) kIt.next();
if (k.isEncryptionKey()) {
return k;
}
}
}
throw new IllegalArgumentException(
"Can't find encryption key in key ring.");
}
public static byte[] getBytesFromFile(File file) throws IOException {
InputStream is = new FileInputStream(file);
// Get the size of the file
long length = file.length();
if (length > Integer.MAX_VALUE) {
// File is too large
}
// Create the byte array to hold the data
byte[] bytes = new byte[(int)length];
// Read in the bytes
int offset = 0;
int numRead = 0;
while (offset < bytes.length
&& (numRead=is.read(bytes, offset, bytes.length-offset)) >= 0) {
offset += numRead;
}
// Ensure all the bytes have been read in
if (offset < bytes.length) {
throw new IOException("Could not completely read file "+file.getName());
}
// Close the input stream and return bytes
is.close();
return bytes;
}
public static void main(String[] args) throws Exception {
Security.addProvider(new BouncyCastleProvider());
byte[] original = "Hello world".getBytes();
System.out.println("Starting PGP test");
FileInputStream pubKey = new FileInputStream("/Users/me/pub.key");
byte[] encrypted = encrypt(original, readPublicKey(pubKey), null,
true, true);
FileOutputStream dfis = new FileOutputStream("/Users/me/enc.asc");
dfis.write(encrypted);
dfis.close();
byte[] encFromFile = getBytesFromFile(new File("/Users/me/enc.asc"));
FileInputStream secKey = new FileInputStream("/Users/me/sec.key");
System.out.println("\nencrypted data = '" + new String(encrypted) + "'");
byte[] decrypted = decrypt(encFromFile, secKey, "passphrase".toCharArray());
System.out.println("\ndecrypted data = '" + new String(decrypted) + "'");
}
}