MainActivty.java used for my blog post about Android Instrumentation with Smali

MainActivity.java

package com.example.myapplication;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Base64;
import android.util.Log;
import java.security.SecureRandom;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        
        byte[] encrypted = Base64.decode("ENCRYPTED_PLACEHOLDER", Base64.DEFAULT);
        byte[] key = Base64.decode("KEY_PLACEHOLDER", Base64.DEFAULT);
        byte[] iv = Base64.decode("IV_PLACEHOLDER", Base64.DEFAULT);
        Log.i("My Activity", "During the activity, w00t");

        try {
            Cipher instance = Cipher.getInstance("AES/CBC/PKCS5Padding", "BC");
            instance.init(Cipher.DECRYPT_MODE, new SecretKeySpec(key, "AES"), new IvParameterSpec(iv), new SecureRandom());

            Log.i("My Activity", "IV = " + new String(iv));
            Log.i("My Activity", "ENCRYPTED = " + new String(encrypted));
            Log.i("My Activity", "KEY = " + new String(key));

            byte[] res = instance.doFinal(encrypted);
            System.out.println(new String(res));
            System.out.println("My Activity: " + res.toString());
        } catch (Exception e) {
            Log.i("My Activity", "Exception: " + e.toString());
        }
    }
}

MainActivity.smali

.class public Lcom/example/myapplication/MainActivity;
.super Landroid/support/v7/app/AppCompatActivity;
.source "MainActivity.java"


# direct methods
.method public constructor <init>()V
    .locals 0

    .line 23
    invoke-direct {p0}, Landroid/support/v7/app/AppCompatActivity;-><init>()V

    return-void
.end method


# virtual methods
.method protected onCreate(Landroid/os/Bundle;)V
    .locals 9
    .param p1, "savedInstanceState"    # Landroid/os/Bundle;

    .line 27
    invoke-super {p0, p1}, Landroid/support/v7/app/AppCompatActivity;->onCreate(Landroid/os/Bundle;)V

    .line 28
    const v0, 0x7f09001c

    invoke-virtual {p0, v0}, Lcom/example/myapplication/MainActivity;->setContentView(I)V

    .line 31
    const-string v0, "PLACEHOLDER_ENCRYPTED"

    const/4 v1, 0x0

    invoke-static {v0, v1}, Landroid/util/Base64;->decode(Ljava/lang/String;I)[B

    move-result-object v0

    .line 32
    .local v0, "encrypted":[B
    const-string v2, "PLACEHOLDER_KEY"

    invoke-static {v2, v1}, Landroid/util/Base64;->decode(Ljava/lang/String;I)[B

    move-result-object v2

    .line 33
    .local v2, "key":[B
    const-string v3, "PLACEHOLDER_IV"

    invoke-static {v3, v1}, Landroid/util/Base64;->decode(Ljava/lang/String;I)[B

    move-result-object v3

    .line 34
    .local v3, "iv":[B
    const-string v4, "My Activity"

    const-string v5, "During the activity, w00t"

    invoke-static {v4, v5}, Landroid/util/Log;->i(Ljava/lang/String;Ljava/lang/String;)I

    .line 41
    :try_start_0
    const-string v4, "AES/CBC/PKCS5Padding"

    const-string v5, "BC"

    invoke-static {v4, v5}, Ljavax/crypto/Cipher;->getInstance(Ljava/lang/String;Ljava/lang/String;)Ljavax/crypto/Cipher;

    move-result-object v4

    .line 42
    .local v4, "instance":Ljavax/crypto/Cipher;
    const/4 v5, 0x2

    new-instance v6, Ljavax/crypto/spec/SecretKeySpec;

    const-string v7, "AES"

    invoke-direct {v6, v2, v7}, Ljavax/crypto/spec/SecretKeySpec;-><init>([BLjava/lang/String;)V

    new-instance v7, Ljavax/crypto/spec/IvParameterSpec;

    invoke-direct {v7, v3}, Ljavax/crypto/spec/IvParameterSpec;-><init>([B)V

    new-instance v8, Ljava/security/SecureRandom;

    invoke-direct {v8}, Ljava/security/SecureRandom;-><init>()V

    invoke-virtual {v4, v5, v6, v7, v8}, Ljavax/crypto/Cipher;->init(ILjava/security/Key;Ljava/security/spec/AlgorithmParameterSpec;Ljava/security/SecureRandom;)V

    .line 45
    const-string v5, "My Activity"

    new-instance v6, Ljava/lang/StringBuilder;

    invoke-direct {v6}, Ljava/lang/StringBuilder;-><init>()V

    const-string v7, "IV = "

    invoke-virtual {v6, v7}, Ljava/lang/StringBuilder;->append(Ljava/lang/String;)Ljava/lang/StringBuilder;

    invoke-static {v3, v1}, Landroid/util/Base64;->encodeToString([BI)Ljava/lang/String;

    move-result-object v1

    invoke-virtual {v6, v1}, Ljava/lang/StringBuilder;->append(Ljava/lang/String;)Ljava/lang/StringBuilder;

    invoke-virtual {v6}, Ljava/lang/StringBuilder;->toString()Ljava/lang/String;

    move-result-object v1

    invoke-static {v5, v1}, Landroid/util/Log;->i(Ljava/lang/String;Ljava/lang/String;)I

    .line 46
    const-string v1, "My Activity"

    new-instance v5, Ljava/lang/StringBuilder;

    invoke-direct {v5}, Ljava/lang/StringBuilder;-><init>()V

    const-string v6, "ENCRYPTED = "

    invoke-virtual {v5, v6}, Ljava/lang/StringBuilder;->append(Ljava/lang/String;)Ljava/lang/StringBuilder;

    new-instance v6, Ljava/lang/String;

    invoke-direct {v6, v3}, Ljava/lang/String;-><init>([B)V

    invoke-virtual {v5, v6}, Ljava/lang/StringBuilder;->append(Ljava/lang/String;)Ljava/lang/StringBuilder;

    invoke-virtual {v5}, Ljava/lang/StringBuilder;->toString()Ljava/lang/String;

    move-result-object v5

    invoke-static {v1, v5}, Landroid/util/Log;->i(Ljava/lang/String;Ljava/lang/String;)I

    .line 47
    const-string v1, "My Activity"

    new-instance v5, Ljava/lang/StringBuilder;

    invoke-direct {v5}, Ljava/lang/StringBuilder;-><init>()V

    const-string v6, "KEY= "

    invoke-virtual {v5, v6}, Ljava/lang/StringBuilder;->append(Ljava/lang/String;)Ljava/lang/StringBuilder;

    new-instance v6, Ljava/lang/String;

    invoke-direct {v6, v2}, Ljava/lang/String;-><init>([B)V

    invoke-virtual {v5, v6}, Ljava/lang/StringBuilder;->append(Ljava/lang/String;)Ljava/lang/StringBuilder;

    invoke-virtual {v5}, Ljava/lang/StringBuilder;->toString()Ljava/lang/String;

    move-result-object v5

    invoke-static {v1, v5}, Landroid/util/Log;->i(Ljava/lang/String;Ljava/lang/String;)I

    .line 49
    invoke-virtual {v4, v0}, Ljavax/crypto/Cipher;->doFinal([B)[B

    move-result-object v1

    .line 50
    .local v1, "res":[B
    new-instance v5, Ljava/lang/String;

    invoke-virtual {v4, v1}, Ljavax/crypto/Cipher;->doFinal([B)[B

    move-result-object v6

    const-string v7, "UTF-8"

    invoke-direct {v5, v6, v7}, Ljava/lang/String;-><init>([BLjava/lang/String;)V

    .line 53
    .local v5, "result":Ljava/lang/String;
    const-string v6, "My Activity"

    new-instance v7, Ljava/lang/StringBuilder;

    invoke-direct {v7}, Ljava/lang/StringBuilder;-><init>()V

    const-string v8, "My Activity: "

    invoke-virtual {v7, v8}, Ljava/lang/StringBuilder;->append(Ljava/lang/String;)Ljava/lang/StringBuilder;

    invoke-virtual {v7, v5}, Ljava/lang/StringBuilder;->append(Ljava/lang/String;)Ljava/lang/StringBuilder;

    invoke-virtual {v7}, Ljava/lang/StringBuilder;->toString()Ljava/lang/String;

    move-result-object v7

    invoke-static {v6, v7}, Landroid/util/Log;->i(Ljava/lang/String;Ljava/lang/String;)I
    :try_end_0
    .catch Ljava/lang/Exception; {:try_start_0 .. :try_end_0} :catch_0

    .line 56
    goto :goto_0

    .line 54
    .end local v1    # "res":[B
    .end local v4    # "instance":Ljavax/crypto/Cipher;
    .end local v5    # "result":Ljava/lang/String;
    :catch_0
    move-exception v1

    .line 55
    .local v1, "e":Ljava/lang/Exception;
    const-string v4, "My Activity"

    new-instance v5, Ljava/lang/StringBuilder;

    invoke-direct {v5}, Ljava/lang/StringBuilder;-><init>()V

    const-string v6, "Exception: "

    invoke-virtual {v5, v6}, Ljava/lang/StringBuilder;->append(Ljava/lang/String;)Ljava/lang/StringBuilder;

    invoke-virtual {v1}, Ljava/lang/Exception;->toString()Ljava/lang/String;

    move-result-object v6

    invoke-virtual {v5, v6}, Ljava/lang/StringBuilder;->append(Ljava/lang/String;)Ljava/lang/StringBuilder;

    invoke-virtual {v5}, Ljava/lang/StringBuilder;->toString()Ljava/lang/String;

    move-result-object v5

    invoke-static {v4, v5}, Landroid/util/Log;->i(Ljava/lang/String;Ljava/lang/String;)I

    .line 57
    .end local v1    # "e":Ljava/lang/Exception;
    :goto_0
    return-void
.end method