some playing with content stream decryption and providing the result as content stream

This commit is contained in:
Thialfihar 2010-07-09 11:28:39 +00:00
parent f03b349057
commit 3ac472125a
3 changed files with 116 additions and 35 deletions

View File

@ -37,7 +37,6 @@ import java.util.Date;
import java.util.GregorianCalendar;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Vector;
import java.util.regex.Pattern;
@ -118,7 +117,8 @@ public class Apg {
public static final String EXTRA_STATUS = "status";
public static final String EXTRA_ERROR = "error";
public static final String EXTRA_DECRYPTED_MESSAGE = "decryptedMessage";
public static final String EXTRA_ENCRYPTED_MESSAGE = "decryptedMessage";
public static final String EXTRA_ENCRYPTED_MESSAGE = "encryptedMessage";
public static final String EXTRA_RESULT_URI = "resultUri";
public static final String EXTRA_SIGNATURE = "signature";
public static final String EXTRA_SIGNATURE_KEY_ID = "signatureKeyId";
public static final String EXTRA_SIGNATURE_USER_ID = "signatureUserId";
@ -1851,4 +1851,43 @@ public class Apg {
public static String getFullVersion(Context context) {
return "APG v" + getVersion(context);
}
public static String generateRandomString(int length) {
SecureRandom random = new SecureRandom();
/*
try {
random = SecureRandom.getInstance("SHA1PRNG", new BouncyCastleProvider());
} catch (NoSuchAlgorithmException e) {
// TODO: need to handle this case somehow
return null;
}*/
byte bytes[] = new byte[length];
random.nextBytes(bytes);
String result = "";
for (int i = 0; i < length; ++i) {
int v = ((int)bytes[i] + 256) % 64;
if (v < 10) {
result += (char)((int)'0' + v);
} else if (v < 36) {
result += (char)((int)'A' + v - 10);
} else if (v < 62) {
result += (char)((int)'a' + v - 36);
} else if (v == 62) {
result += '_';
} else if (v == 63) {
result += '.';
}
}
return result;
}
static long getLengthOfStream(InputStream in) throws IOException {
long size = 0;
long n = 0;
byte dummy[] = new byte[0x10000];
while ((n = in.read(dummy)) > 0) {
size += n;
}
return size;
}
}

View File

@ -31,6 +31,7 @@ import java.util.regex.Matcher;
import org.bouncycastle2.jce.provider.BouncyCastleProvider;
import org.bouncycastle2.openpgp.PGPException;
import org.thialfihar.android.apg.provider.DataProvider;
import android.app.Dialog;
import android.content.ActivityNotFoundException;
@ -86,6 +87,8 @@ public class DecryptActivity extends BaseActivity {
private String mInputFilename = null;
private String mOutputFilename = null;
private Uri mContentUri = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
@ -220,26 +223,29 @@ public class DecryptActivity extends BaseActivity {
mSource.showNext();
}
} else if (Apg.Intent.DECRYPT_AND_RETURN.equals(mIntent.getAction())) {
Bundle extras = mIntent.getExtras();
if (extras == null) {
extras = new Bundle();
}
String data = extras.getString(Apg.EXTRA_TEXT);
if (data != null) {
Matcher matcher = Apg.PGP_MESSAGE.matcher(data);
if (matcher.matches()) {
data = matcher.group(1);
// replace non breakable spaces
data = data.replaceAll("\\xa0", " ");
mMessage.setText(data);
} else {
matcher = Apg.PGP_SIGNED_MESSAGE.matcher(data);
mContentUri = mIntent.getData();
if (mContentUri == null) {
Bundle extras = mIntent.getExtras();
if (extras == null) {
extras = new Bundle();
}
String data = extras.getString(Apg.EXTRA_TEXT);
if (data != null) {
Matcher matcher = Apg.PGP_MESSAGE.matcher(data);
if (matcher.matches()) {
data = matcher.group(1);
// replace non breakable spaces
data = data.replaceAll("\\xa0", " ");
mMessage.setText(data);
mDecryptButton.setText(R.string.btn_verify);
} else {
matcher = Apg.PGP_SIGNED_MESSAGE.matcher(data);
if (matcher.matches()) {
data = matcher.group(1);
// replace non breakable spaces
data = data.replaceAll("\\xa0", " ");
mMessage.setText(data);
mDecryptButton.setText(R.string.btn_verify);
}
}
}
}
@ -393,7 +399,9 @@ public class DecryptActivity extends BaseActivity {
String error = null;
try {
InputStream in;
if (mDecryptTarget == Id.target.file) {
if (mContentUri != null) {
in = getContentResolver().openInputStream(mContentUri);
} else if (mDecryptTarget == Id.target.file) {
if (mInputFilename.startsWith("file")) {
in = new FileInputStream(mInputFilename);
} else {
@ -412,7 +420,9 @@ public class DecryptActivity extends BaseActivity {
setSecretKeyId(Id.key.symmetric);
// look at the file/message again to check whether there's
// symmetric encryption data in there
if (mDecryptTarget == Id.target.file) {
if (mContentUri != null) {
in = getContentResolver().openInputStream(mContentUri);
} else if (mDecryptTarget == Id.target.file) {
if (mInputFilename.startsWith("file")) {
in = new FileInputStream(mInputFilename);
} else {
@ -494,22 +504,32 @@ public class DecryptActivity extends BaseActivity {
try {
PositionAwareInputStream in = null;
OutputStream out = null;
String randomString = null;
long size = 0;
if (mDecryptTarget == Id.target.message) {
if (mContentUri != null) {
in = new PositionAwareInputStream(getContentResolver().openInputStream(mContentUri));
size = Apg.getLengthOfStream(getContentResolver().openInputStream(mContentUri));
try {
while (true) {
randomString = Apg.generateRandomString(32);
if (randomString == null) {
throw new Apg.GeneralException("couldn't generate random file name");
}
this.openFileInput(randomString).close();
}
} catch (FileNotFoundException e) {
// found a name that isn't used yet
}
out = openFileOutput(randomString, MODE_PRIVATE);
} else if (mDecryptTarget == Id.target.message) {
String messageData = mMessage.getText().toString();
in = new PositionAwareInputStream(new ByteArrayInputStream(messageData.getBytes()));
out = new ByteArrayOutputStream();
size = messageData.getBytes().length;
} else {
if (mInputFilename.startsWith("content")) {
InputStream tmp = getContentResolver().openInputStream(Uri.parse(mInputFilename));
size = 0;
long n = 0;
byte dummy[] = new byte[0x10000];
while ((n = tmp.read(dummy)) > 0) {
size += n;
}
size = Apg.getLengthOfStream(getContentResolver().openInputStream(Uri.parse(mInputFilename)));
in = new PositionAwareInputStream(
getContentResolver().openInputStream(Uri.parse(mInputFilename)));
} else {
@ -528,7 +548,10 @@ public class DecryptActivity extends BaseActivity {
}
out.close();
if (mDecryptTarget == Id.target.message) {
if (randomString != null) {
data.putString(Apg.EXTRA_RESULT_URI, "content://" + DataProvider.AUTHORITY + "/data/" + randomString);
} else if (mDecryptTarget == Id.target.message) {
data.putString(Apg.EXTRA_DECRYPTED_MESSAGE,
new String(((ByteArrayOutputStream) out).toByteArray()));
}
@ -570,6 +593,14 @@ public class DecryptActivity extends BaseActivity {
}
Toast.makeText(this, R.string.decryptionSuccessful, Toast.LENGTH_SHORT).show();
if (mReturnResult) {
Intent intent = new Intent();
intent.putExtras(data);
setResult(RESULT_OK, intent);
finish();
return;
}
switch (mDecryptTarget) {
case Id.target.message: {
String decryptedMessage = data.getString(Apg.EXTRA_DECRYPTED_MESSAGE);
@ -616,13 +647,6 @@ public class DecryptActivity extends BaseActivity {
}
mSignatureLayout.setVisibility(View.VISIBLE);
}
if (mReturnResult) {
Intent intent = new Intent();
intent.putExtras(data);
setResult(RESULT_OK, intent);
finish();
}
}
@Override

View File

@ -16,6 +16,8 @@
package org.thialfihar.android.apg.provider;
import java.io.File;
import java.io.FileNotFoundException;
import java.util.HashMap;
import org.thialfihar.android.apg.Id;
@ -27,6 +29,7 @@ import android.database.Cursor;
import android.database.DatabaseUtils;
import android.database.sqlite.SQLiteQueryBuilder;
import android.net.Uri;
import android.os.ParcelFileDescriptor;
import android.text.TextUtils;
public class DataProvider extends ContentProvider {
@ -50,6 +53,8 @@ public class DataProvider extends ContentProvider {
private static final int SECRET_KEY_RING_USER_ID = 221;
private static final int SECRET_KEY_RING_USER_ID_RANK = 222;
private static final int DATA_STREAM = 301;
private static final String PUBLIC_KEY_RING_CONTENT_DIR_TYPE =
"vnd.android.cursor.dir/vnd.thialfihar.apg.public.key_ring";
private static final String PUBLIC_KEY_RING_CONTENT_ITEM_TYPE =
@ -109,6 +114,8 @@ public class DataProvider extends ContentProvider {
mUriMatcher.addURI(AUTHORITY, "key_rings/secret", SECRET_KEY_RING);
mUriMatcher.addURI(AUTHORITY, "key_rings/secret/*", SECRET_KEY_RING_ID);
mUriMatcher.addURI(AUTHORITY, "data/*", DATA_STREAM);
}
@Override
@ -360,4 +367,15 @@ public class DataProvider extends ContentProvider {
// not supported
return 0;
}
@Override
public ParcelFileDescriptor openFile(Uri uri, String mode) throws FileNotFoundException {
int match = mUriMatcher.match(uri);
if (match != DATA_STREAM) {
throw new FileNotFoundException();
}
String fileName = uri.getPathSegments().get(1);
File file = new File(getContext().getFilesDir().getAbsolutePath(), fileName);
return ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY);
}
}