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@PaulSec
Last active June 28, 2020 13:14
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MainActivty.java used for my blog post about Android Instrumentation with Smali
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());
}
}
}
.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
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