【愚公系列】2021年12月 攻防世界-简单题-MOBILE-005(easy-apk)

package com.testjava.jack.pingan1;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

/* loaded from: classes.dex */
public class MainActivity extends AppCompatActivity {
    /* JADX INFO: Access modifiers changed from: protected */
    @Override // android.support.v7.app.AppCompatActivity, android.support.v4.app.FragmentActivity, android.support.v4.app.SupportActivity, android.app.Activity
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ((Button) findViewById(R.id.button)).setOnClickListener(new View.OnClickListener() { // from class: com.testjava.jack.pingan1.MainActivity.1
            @Override // android.view.View.OnClickListener
            public void onClick(View view) {
                if (new Base64New().Base64Encode(((EditText) MainActivity.this.findViewById(R.id.editText)).getText().toString().getBytes()).equals("5rFf7E2K6rqN7Hpiyush7E6S5fJg6rsi5NBf6NGT5rs=")) {
                    Toast.makeText(MainActivity.this, "验证通过!", 1).show();
                } else {
                    Toast.makeText(MainActivity.this, "验证失败!", 1).show();
                }
            }
        });
    }
}

package com.testjava.jack.pingan1;

/* loaded from: classes.dex */
public class Base64New {
    private static final int RANGE = 255;
    private static final char[] Base64ByteToStr = {'v', 'w', 'x', 'r', 's', 't', 'u', 'o', 'p', 'q', '3', '4', '5', '6', '7', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'y', 'z', '0', '1', '2', 'P', 'Q', 'R', 'S', 'T', 'K', 'L', 'M', 'N', 'O', 'Z', 'a', 'b', 'c', 'd', 'U', 'V', 'W', 'X', 'Y', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', '8', '9', '+', '/'};
    private static byte[] StrToBase64Byte = new byte[128];

    public String Base64Encode(byte[] bytes) {
        StringBuilder res = new StringBuilder();
        for (int i = 0; i <= bytes.length - 1; i += 3) {
            byte[] enBytes = new byte[4];
            byte tmp = 0;
            for (int k = 0; k <= 2; k++) {
                if (i + k <= bytes.length - 1) {
                    enBytes[k] = (byte) (((bytes[i + k] & 255) >>> ((k * 2) + 2)) | tmp);
                    tmp = (byte) ((((bytes[i + k] & 255) << (((2 - k) * 2) + 2)) & 255) >>> 2);
                } else {
                    enBytes[k] = tmp;
                    tmp = 64;
                }
            }
            enBytes[3] = tmp;
            for (int k2 = 0; k2 <= 3; k2++) {
                if (enBytes[k2] <= 63) {
                    res.append(Base64ByteToStr[enBytes[k2]]);
                } else {
                    res.append('=');
                }
            }
        }
        return res.toString();
    }
}

from hashlib import *
def base64_decode(str_list):
	list_base = []
	# 第一个左移两位
	a = str_list[0] << 2
	# 第二个字符低4位
	c = str_list[1] & 15
	# 加上第二个高2位
	b = str_list[1] >> 4
	# 第一个转换字符 6 + 2(剩下4)
	a = a | b
	list_base.append(a)
	# 左移4位
	c = c << 4
	# 第三个字符低2位
	a = str_list[2] & 3
	# 第三个字符高4位
	b = str_list[2] >> 2
	# 第二个转换字符 4 + 4(剩下2)
	c = c | b
	list_base.append(c)
	# 第三个字符低2位左移6位
	a = a << 6
	# 加上第四个字符
	a = a | str_list[3]
	# 第三个转换字符
	list_base.append(a)
	return list_base
byte_to_str = ['v', 'w', 'x', 'r', 's', 't', 'u', 'o',
'p', 'q', '3', '4', '5', '6', '7', 'A',
'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I',
'J', 'y', 'z', '0', '1', '2', 'P', 'Q',
'R', 'S', 'T', 'K', 'L', 'M', 'N', 'O',
'Z', 'a', 'b', 'c', 'd', 'U', 'V', 'W',
'X', 'Y', 'e', 'f', 'g', 'h', 'i', 'j',
'k', 'l', 'm', 'n', '8', '9', '+', '/']
table = "".join([i for i in byte_to_str])
cipher_test = '5rFf7E2K6rqN7Hpiyush7E6S5fJg6rsi5NBf6NGT5rs='
ans = ''
i = 0
while i <= len(cipher_test) - 1:
	list1 = []
	equal_num = 0
	for k in range(4):
		if cipher_test[i+k] is '=':
			list1.append(0)
			equal_num += 1
		else:
			list1.append(table.index(cipher_test[i+k]))
	ba = base64_decode(list1)
	for j in range(3-equal_num):
		ch = chr(ba[j])
		ans += str(ch)
	i += 4
flag = 'flag{' + format(ans) + '}'
print(flag)