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Android Encryption / Decryption Problem (AES)

I need a little help here. So basically I have to do an AES encryption / decryption test on Android. I am new to Android programming and why my friend gives me an example of how to do this, but the problem is that when I run the sample, it crashes after 20-30 seconds, and I'm not quite sure what is happening. So someone can look at the code and tell me where the problem is. An example of the code you need to do is: Encrypt and decrypt the same image and show me a log with information about how long it takes to encrypt and decrypt the image. Thank you anyway!

Code:

package com.cryptooo.lol; import java.io.ByteArrayOutputStream; import java.security.SecureRandom; import javax.crypto.Cipher; import javax.crypto.KeyGenerator; import javax.crypto.SecretKey; import javax.crypto.spec.SecretKeySpec; import android.app.Activity; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.os.Bundle; public class SimpleCryptoActivity extends Activity { @Override public void onCreate(Bundle savedInstanceState){ super.onCreate(savedInstanceState); setContentView(R.layout.main); new Thread() { public void run(){ Bitmap bm = BitmapFactory.decodeResource(getResources(), R.drawable.shit); ByteArrayOutputStream baos = new ByteArrayOutputStream(); bm.compress(Bitmap.CompressFormat.PNG, 100, baos); // bm is the bitmap object byte[] b = baos.toByteArray(); try { byte[] keyStart = "MARTIN_123_MARTIN_123".getBytes(); KeyGenerator kgen = KeyGenerator.getInstance("AES"); SecureRandom sr = SecureRandom.getInstance("SHA1PRNG"); sr.setSeed(keyStart); kgen.init(128, sr); // 192 and 256 bits may not be available SecretKey skey = kgen.generateKey(); byte[] key = skey.getEncoded(); // encrypt byte[] encryptedData = encrypt(key,b); // decrypt long start = System.currentTimeMillis()/1000L; byte[] decryptedData = decrypt(key,encryptedData); long end = System.currentTimeMillis()/1000L; android.util.Log.d("TEST","Time "+ String.valueOf(end-start)); } catch(Exception e){ e.fillInStackTrace(); } } private byte[] encrypt(byte[] raw, byte[] clear) throws Exception { SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES"); Cipher cipher = Cipher.getInstance("AES"); cipher.init(Cipher.ENCRYPT_MODE, skeySpec); byte[] encrypted = cipher.doFinal(clear); return encrypted; } private byte[] decrypt(byte[] raw, byte[] encrypted) throws Exception { SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES"); Cipher cipher = Cipher.getInstance("AES"); cipher.init(Cipher.DECRYPT_MODE, skeySpec); byte[] decrypted = cipher.doFinal(encrypted); return decrypted; } }.start(); } }

and here is LogCat:

 07-25 09:53:01.243: DEBUG/AndroidRuntime(624): >>>>>>>>>>>>>> AndroidRuntime START <<<<<<<<<<<<<< 07-25 09:53:01.253: DEBUG/AndroidRuntime(624): CheckJNI is ON 07-25 09:53:01.463: DEBUG/AndroidRuntime(624): --- registering native functions --- 07-25 09:53:01.843: DEBUG/ddm-heap(624): Got feature list request 07-25 09:53:02.234: DEBUG/PackageParser(52): Scanning package: /data/app/vmdl26130.tmp 07-25 09:53:02.364: INFO/PackageManager(52): Removing non-system package:com.cryptooo.lol 07-25 09:53:02.373: DEBUG/PackageManager(52): Removing package com.cryptooo.lol 07-25 09:53:02.373: DEBUG/PackageManager(52): Activities: com.cryptooo.lol.SimpleCryptoActivity 07-25 09:53:02.464: DEBUG/PackageManager(52): Scanning package com.cryptooo.lol 07-25 09:53:02.464: INFO/PackageManager(52): /data/app/vmdl26130.tmp changed; unpacking 07-25 09:53:02.484: DEBUG/installd(32): DexInv: --- BEGIN '/data/app/vmdl26130.tmp' --- 07-25 09:53:02.713: DEBUG/dalvikvm(630): DexOpt: load 44ms, verify 27ms, opt 1ms 07-25 09:53:02.723: DEBUG/installd(32): DexInv: --- END '/data/app/vmdl26130.tmp' (success) --- 07-25 09:53:02.723: DEBUG/PackageManager(52): Activities: com.cryptooo.lol.SimpleCryptoActivity 07-25 09:53:02.745: DEBUG/ActivityManager(52): Uninstalling process com.cryptooo.lol 07-25 09:53:02.833: INFO/installd(32): move /data/dalvik-cache/ data@app @ vmdl26130.tmp@classes.dex -> /data/dalvik-cache/ data@app @ com.cryptooo.lol.apk@classes.dex 07-25 09:53:02.843: DEBUG/PackageManager(52): New package installed in /data/app/com.cryptooo.lol.apk 07-25 09:53:02.973: DEBUG/AndroidRuntime(624): Shutting down VM 07-25 09:53:02.973: DEBUG/dalvikvm(624): DestroyJavaVM waiting for non-daemon threads to exit 07-25 09:53:02.985: DEBUG/dalvikvm(624): DestroyJavaVM shutting VM down 07-25 09:53:02.985: DEBUG/dalvikvm(624): HeapWorker thread shutting down 07-25 09:53:02.985: DEBUG/dalvikvm(624): HeapWorker thread has shut down 07-25 09:53:02.985: DEBUG/jdwp(624): JDWP shutting down net... 07-25 09:53:02.985: INFO/dalvikvm(624): Debugger has detached; object registry had 1 entries 07-25 09:53:02.985: DEBUG/dalvikvm(624): VM cleaning up 07-25 09:53:03.004: DEBUG/ActivityManager(52): Uninstalling process com.cryptooo.lol 07-25 09:53:03.024: DEBUG/dalvikvm(624): LinearAlloc 0x0 used 623916 of 5242880 (11%) 07-25 09:53:03.024: ERROR/AndroidRuntime(624): ERROR: thread attach failed 07-25 09:53:03.223: WARN/ResourceType(52): Resources don't contain package for resource number 0x7f0700e5 07-25 09:53:03.235: WARN/ResourceType(52): Resources don't contain package for resource number 0x7f020031 07-25 09:53:03.235: WARN/ResourceType(52): Resources don't contain package for resource number 0x7f020030 07-25 09:53:03.235: WARN/ResourceType(52): Resources don't contain package for resource number 0x7f050000 07-25 09:53:03.284: WARN/ResourceType(52): Resources don't contain package for resource number 0x7f060000 07-25 09:53:03.284: WARN/ResourceType(52): Resources don't contain package for resource number 0x7f060001 07-25 09:53:03.473: DEBUG/dalvikvm(98): GC freed 149 objects / 7384 bytes in 244ms 07-25 09:53:03.583: WARN/dalvikvm(52): threadid=15: spin on suspend #0 threadid=21 (h=1324960) 07-25 09:53:03.593: WARN/dalvikvm(52): dumping state: process - 52 07-25 09:53:03.593: INFO/dalvikvm(52): "android.server.ServerThread" prio=5 tid=15 RUNNABLE 07-25 09:53:03.593: INFO/dalvikvm(52): | group="main" sCount=0 dsCount=0 s=N obj=0x44c017e0 self=0x147d30 07-25 09:53:03.593: INFO/dalvikvm(52): | sysTid=61 nice=-2 sched=0/0 cgrp=default handle=1306264 07-25 09:53:03.593: INFO/dalvikvm(52): at java.lang.Runtime.gc(Native Method) 07-25 09:53:03.593: INFO/dalvikvm(52): at com.android.internal.os.BinderInternal.forceGc(BinderInternal.java:83) 07-25 09:53:03.593: INFO/dalvikvm(52): at android.app.ActivityThread.doGcIfNeeded(ActivityThread.java:2296) 07-25 09:53:03.593: INFO/dalvikvm(52): at android.app.ActivityThread$GcIdler.queueIdle(ActivityThread.java:2010) 07-25 09:53:03.593: INFO/dalvikvm(52): at android.os.MessageQueue.next(MessageQueue.java:116) 07-25 09:53:03.593: INFO/dalvikvm(52): at android.os.Looper.loop(Looper.java:110) 07-25 09:53:03.593: INFO/dalvikvm(52): at com.android.server.ServerThread.run(SystemServer.java:428) 07-25 09:53:03.605: INFO/dalvikvm(52): "PackageManager" prio=5 tid=21 RUNNABLE 07-25 09:53:03.605: INFO/dalvikvm(52): | group="main" sCount=1 dsCount=0 s=N obj=0x44c37b10 self=0x11fb40 07-25 09:53:03.605: INFO/dalvikvm(52): | sysTid=67 nice=10 sched=0/0 cgrp=bg_non_interactive handle=1324960 07-25 09:53:03.695: INFO/dalvikvm(52): at com.android.server.am.ActivityManagerService.broadcastIntent(ActivityManagerService.java:~12017) 07-25 09:53:03.695: INFO/dalvikvm(52): at com.android.server.PackageManagerService.sendPackageBroadcast(PackageManagerService.java:3662) 07-25 09:53:03.695: INFO/dalvikvm(52): at com.android.server.PackageManagerService.access$1400(PackageManagerService.java:109) 07-25 09:53:03.695: INFO/dalvikvm(52): at com.android.server.PackageManagerService$PackageRemovedInfo.sendBroadcast(PackageManagerService.java:4533) 07-25 09:53:03.695: INFO/dalvikvm(52): at com.android.server.PackageManagerService$5.run(PackageManagerService.java:3792) 07-25 09:53:03.695: INFO/dalvikvm(52): at android.os.Handler.handleCallback(Handler.java:587) 07-25 09:53:03.695: INFO/dalvikvm(52): at android.os.Handler.dispatchMessage(Handler.java:92) 07-25 09:53:03.695: INFO/dalvikvm(52): at android.os.Looper.loop(Looper.java:123) 07-25 09:53:03.695: INFO/dalvikvm(52): at android.os.HandlerThread.run(HandlerThread.java:60) 07-25 09:53:03.714: WARN/dalvikvm(52): threadid=15: spin on suspend resolved in 373 msec 07-25 09:53:03.984: DEBUG/dalvikvm(52): GC freed 22016 objects / 1235352 bytes in 643ms 07-25 09:53:04.064: DEBUG/AndroidRuntime(635): >>>>>>>>>>>>>> AndroidRuntime START <<<<<<<<<<<<<< 07-25 09:53:04.083: DEBUG/AndroidRuntime(635): CheckJNI is ON 07-25 09:53:04.404: DEBUG/AndroidRuntime(635): --- registering native functions --- 07-25 09:53:04.905: WARN/ResourceType(52): Resources don't contain package for resource number 0x7f0700e5 07-25 09:53:04.905: WARN/ResourceType(52): Resources don't contain package for resource number 0x7f020031 07-25 09:53:04.905: WARN/ResourceType(52): Resources don't contain package for resource number 0x7f020030 07-25 09:53:04.905: WARN/ResourceType(52): Resources don't contain package for resource number 0x7f050000 07-25 09:53:05.013: WARN/ResourceType(52): Resources don't contain package for resource number 0x7f060000 07-25 09:53:05.034: WARN/ResourceType(52): Resources don't contain package for resource number 0x7f060001 07-25 09:53:05.064: DEBUG/ddm-heap(635): Got feature list request 07-25 09:53:05.824: DEBUG/dalvikvm(52): GC freed 4805 objects / 259312 bytes in 480ms 07-25 09:53:05.933: DEBUG/ActivityManager(52): Uninstalling process com.cryptooo.lol 07-25 09:53:05.933: INFO/ActivityManager(52): Starting activity: Intent { act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] flg=0x10000000 cmp=com.cryptooo.lol/.SimpleCryptoActivity } 07-25 09:53:05.984: DEBUG/AndroidRuntime(635): Shutting down VM 07-25 09:53:05.984: DEBUG/dalvikvm(635): DestroyJavaVM waiting for non-daemon threads to exit 07-25 09:53:05.993: DEBUG/dalvikvm(635): DestroyJavaVM shutting VM down 07-25 09:53:05.993: DEBUG/dalvikvm(635): HeapWorker thread shutting down 07-25 09:53:06.003: DEBUG/dalvikvm(635): HeapWorker thread has shut down 07-25 09:53:06.003: DEBUG/jdwp(635): JDWP shutting down net... 07-25 09:53:06.003: INFO/dalvikvm(635): Debugger has detached; object registry had 1 entries 07-25 09:53:06.003: DEBUG/dalvikvm(635): VM cleaning up 07-25 09:53:06.043: DEBUG/dalvikvm(635): LinearAlloc 0x0 used 639500 of 5242880 (12%) 07-25 09:53:06.074: ERROR/AndroidRuntime(635): ERROR: thread attach failed 07-25 09:53:06.114: INFO/ActivityManager(52): Start proc com.cryptooo.lol for activity com.cryptooo.lol/.SimpleCryptoActivity: pid=643 uid=10038 gids={} 07-25 09:53:06.344: DEBUG/ddm-heap(643): Got feature list request 07-25 09:53:06.484: WARN/ActivityThread(643): Application com.cryptooo.lol is waiting for the debugger on port 8100... 07-25 09:53:06.513: INFO/System.out(643): Sending WAIT chunk 07-25 09:53:06.584: INFO/dalvikvm(643): Debugger is active 07-25 09:53:06.723: INFO/System.out(643): Debugger has connected 07-25 09:53:06.723: INFO/System.out(643): waiting for debugger to settle... 07-25 09:53:06.924: INFO/System.out(643): waiting for debugger to settle... 07-25 09:53:07.133: INFO/System.out(643): waiting for debugger to settle... 07-25 09:53:07.333: INFO/System.out(643): waiting for debugger to settle... 07-25 09:53:07.533: INFO/System.out(643): waiting for debugger to settle... 07-25 09:53:07.574: DEBUG/dalvikvm(119): GC freed 10191 objects / 487632 bytes in 4140ms 07-25 09:53:07.734: INFO/System.out(643): waiting for debugger to settle... 07-25 09:53:07.937: INFO/System.out(643): waiting for debugger to settle... 07-25 09:53:08.204: INFO/System.out(643): waiting for debugger to settle... 07-25 09:53:08.414: INFO/System.out(643): waiting for debugger to settle... 07-25 09:53:08.644: INFO/System.out(643): waiting for debugger to settle... 07-25 09:53:08.854: INFO/System.out(643): debugger has settled (1465) 07-25 09:53:09.053: ERROR/gralloc(52): [unregister] handle 0x1338a8 still locked (state=40000001) 07-25 09:53:09.473: DEBUG/dalvikvm(643): GC freed 650 objects / 52080 bytes in 159ms 07-25 09:53:09.993: INFO/ActivityManager(52): Displayed activity com.cryptooo.lol/.SimpleCryptoActivity: 4007 ms (total 4007 ms) 07-25 09:53:13.174: DEBUG/dalvikvm(643): GC freed 73 objects / 93640 bytes in 73ms 07-25 09:53:18.924: DEBUG/dalvikvm(264): GC freed 43 objects / 2024 bytes in 3859ms 07-25 09:53:21.714: DEBUG/dalvikvm(98): GC freed 2725 objects / 159280 bytes in 1649ms 07-25 09:53:22.123: DEBUG/dalvikvm(643): GC freed 126 objects / 900328 bytes in 69ms 07-25 09:53:22.154: INFO/dalvikvm-heap(643): Grow heap (frag case) to 12.648MB for 2092136-byte allocation 07-25 09:53:22.335: DEBUG/dalvikvm(643): GC freed 41 objects / 1592 bytes in 176ms 07-25 09:53:30.224: DEBUG/dalvikvm(643): GC freed 3 objects / 1042080 bytes in 70ms 07-25 09:53:30.294: INFO/dalvikvm-heap(643): Grow heap (frag case) to 15.651MB for 4192360-byte allocation 07-25 09:53:30.474: DEBUG/dalvikvm(643): GC freed 0 objects / 0 bytes in 172ms 07-25 09:53:36.184: DEBUG/dalvikvm(643): GC freed 4 objects / 2096320 bytes in 75ms 07-25 09:53:36.214: INFO/dalvikvm-heap(643): Grow heap (frag case) to 16.091MB for 2557851-byte allocation 07-25 09:53:36.413: DEBUG/dalvikvm(643): GC freed 0 objects / 0 bytes in 200ms 07-25 09:53:36.543: DEBUG/dalvikvm(643): GC freed 54 objects / 2936 bytes in 73ms 07-25 09:53:36.583: INFO/dalvikvm-heap(643): Grow heap (frag case) to 18.537MB for 2557856-byte allocation 07-25 09:53:36.766: DEBUG/dalvikvm(643): GC freed 0 objects / 0 bytes in 180ms
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2 answers

About downloading an encrypted image: You can use the /assets folder, located in your workspace at the same level as /res . Then you put the file inside. Let's say this is called "myfile.enc". You must use AssetManager to extract the file:

  AssetManager am = activity.getAssets(); InputStream is = am.open("myfile.enc");

With InputStream, you can write it to ByteArrayOutputStream and then get the bytes, or you can pass it to CipherInputstream instead of calling Cipher.doFinal . This is the way to go if you have a relatively large resource. But for your little test, I think the byte version is the lightest.

To make Bitmap work, I would also put it in a resource folder and then get bytes with the same procedure. The drawables folder is usually used for images that you intend to use in the GUI, so you can use their ID in R.java.

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Two things:

-You are performing an extensive task in the Ui thread (AKA event stream). This is a very bad way to do something, because you are blocking the graphical interface, and if you spend too much time on it, the OS will launch the "Application is not responding" error.

-I think you are not running the view in onCreate.

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