basic pgp support.

2 files changed, 148 insertions, 2 deletions

diff --git a/src/de/gultsch/chat/crypto/OtrEngine.java b/src/de/gultsch/chat/crypto/OtrEngine.java
index 7be9bed3..cdd71d61 100644
--- a/src/de/gultsch/chat/crypto/OtrEngine.java
+++ b/src/de/gultsch/chat/crypto/OtrEngine.java
@@ -93,8 +93,6 @@ public class OtrEngine implements OtrEngineHost {
 			e.printStackTrace();
 		} catch (InvalidKeySpecException e) {
 			e.printStackTrace();
-		} catch (JSONException e) {
-			e.printStackTrace();
 		}
 		
 	}
diff --git a/src/de/gultsch/chat/crypto/PgpEngine.java b/src/de/gultsch/chat/crypto/PgpEngine.java
new file mode 100644
index 00000000..6d94e577
--- /dev/null
+++ b/src/de/gultsch/chat/crypto/PgpEngine.java
@@ -0,0 +1,148 @@
+package de.gultsch.chat.crypto;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.InputStream;
+
+import org.openintents.openpgp.OpenPgpError;
+import org.openintents.openpgp.OpenPgpSignatureResult;
+import org.openintents.openpgp.util.OpenPgpApi;
+import org.openintents.openpgp.util.OpenPgpConstants;
+
+import android.app.PendingIntent;
+import android.os.Bundle;
+import android.util.Log;
+
+public class PgpEngine {
+	private OpenPgpApi api;
+
+	public PgpEngine(OpenPgpApi api) {
+		this.api = api;
+	}
+
+	public String decrypt(String message) throws UserInputRequiredException,
+			OpenPgpException {
+		InputStream is = new ByteArrayInputStream(message.getBytes());
+		ByteArrayOutputStream os = new ByteArrayOutputStream();
+		Bundle result = api.decryptAndVerify(is, os);
+		switch (result.getInt(OpenPgpConstants.RESULT_CODE)) {
+		case OpenPgpConstants.RESULT_CODE_SUCCESS:
+			return os.toString();
+		case OpenPgpConstants.RESULT_CODE_USER_INTERACTION_REQUIRED:
+			throw new UserInputRequiredException(
+					(PendingIntent) result
+							.getParcelable(OpenPgpConstants.RESULT_INTENT));
+		case OpenPgpConstants.RESULT_CODE_ERROR:
+			throw new OpenPgpException(
+					(OpenPgpError) result
+							.getParcelable(OpenPgpConstants.RESULT_ERRORS));
+		default:
+			return null;
+		}
+	}
+
+	public String encrypt(long keyId, String message) {
+		Bundle params = new Bundle();
+		params.putBoolean(OpenPgpConstants.PARAMS_REQUEST_ASCII_ARMOR, true);
+		long[] keyIds = { keyId };
+		params.putLongArray(OpenPgpConstants.PARAMS_KEY_IDS, keyIds);
+
+		InputStream is = new ByteArrayInputStream(message.getBytes());
+		ByteArrayOutputStream os = new ByteArrayOutputStream();
+		Bundle result = api.encrypt(params, is, os);
+		StringBuilder encryptedMessageBody = new StringBuilder();
+		String[] lines = os.toString().split("\n");
+		for (int i = 3; i < lines.length - 1; ++i) {
+			encryptedMessageBody.append(lines[i].trim());
+		}
+		return encryptedMessageBody.toString();
+	}
+
+	public long fetchKeyId(String status, String signature)
+			throws OpenPgpException {
+		StringBuilder pgpSig = new StringBuilder();
+		pgpSig.append("-----BEGIN PGP SIGNED MESSAGE-----");
+		pgpSig.append('\n');
+		pgpSig.append("Hash: SHA1");
+		pgpSig.append('\n');
+		pgpSig.append('\n');
+		pgpSig.append(status);
+		pgpSig.append('\n');
+		pgpSig.append("-----BEGIN PGP SIGNATURE-----");
+		pgpSig.append('\n');
+		pgpSig.append('\n');
+		pgpSig.append(signature.replace("\n", "").trim());
+		pgpSig.append('\n');
+		pgpSig.append("-----END PGP SIGNATURE-----");
+		Bundle params = new Bundle();
+		params.putBoolean(OpenPgpConstants.PARAMS_REQUEST_ASCII_ARMOR, true);
+		InputStream is = new ByteArrayInputStream(pgpSig.toString().getBytes());
+		ByteArrayOutputStream os = new ByteArrayOutputStream();
+		Bundle result = api.decryptAndVerify(params, is, os);
+		switch (result.getInt(OpenPgpConstants.RESULT_CODE)) {
+		case OpenPgpConstants.RESULT_CODE_SUCCESS:
+			OpenPgpSignatureResult sigResult = result
+					.getParcelable(OpenPgpConstants.RESULT_SIGNATURE);
+			return sigResult.getKeyId();
+		case OpenPgpConstants.RESULT_CODE_USER_INTERACTION_REQUIRED:
+			break;
+		case OpenPgpConstants.RESULT_CODE_ERROR:
+			throw new OpenPgpException(
+					(OpenPgpError) result
+							.getParcelable(OpenPgpConstants.RESULT_ERRORS));
+		}
+		return 0;
+	}
+
+	public String generateSignature(String status)
+			throws UserInputRequiredException {
+		Bundle params = new Bundle();
+		params.putBoolean(OpenPgpConstants.PARAMS_REQUEST_ASCII_ARMOR, true);
+		InputStream is = new ByteArrayInputStream(status.getBytes());
+		ByteArrayOutputStream os = new ByteArrayOutputStream();
+		Bundle result = api.sign(params, is, os);
+		StringBuilder signatureBuilder = new StringBuilder();
+		switch (result.getInt(OpenPgpConstants.RESULT_CODE)) {
+		case OpenPgpConstants.RESULT_CODE_SUCCESS:
+			String[] lines = os.toString().split("\n");
+			for (int i = 7; i < lines.length - 1; ++i) {
+				signatureBuilder.append(lines[i].trim());
+			}
+			break;
+		case OpenPgpConstants.RESULT_CODE_USER_INTERACTION_REQUIRED:
+			UserInputRequiredException exception = new UserInputRequiredException(
+					(PendingIntent) result
+							.getParcelable(OpenPgpConstants.RESULT_INTENT));
+			throw exception;
+		case OpenPgpConstants.RESULT_CODE_ERROR:
+			break;
+		}
+		return signatureBuilder.toString();
+	}
+
+	public class UserInputRequiredException extends Exception {
+		private static final long serialVersionUID = -6913480043269132016L;
+		private PendingIntent pi;
+
+		public UserInputRequiredException(PendingIntent pi) {
+			this.pi = pi;
+		}
+
+		public PendingIntent getPendingIntent() {
+			return this.pi;
+		}
+	}
+
+	public class OpenPgpException extends Exception {
+		private static final long serialVersionUID = -7324789703473056077L;
+		private OpenPgpError error;
+
+		public OpenPgpException(OpenPgpError openPgpError) {
+			this.error = openPgpError;
+		}
+
+		public OpenPgpError getOpenPgpError() {
+			return this.error;
+		}
+	}
+}