質問編集履歴
1
DESで復号したソースに修正
title
CHANGED
File without changes
|
body
CHANGED
@@ -95,4 +95,60 @@
|
|
95
95
|
参考:[ttps://itdogkuwaccho.hatenadiary.com/entry/2017/11/12/125140](https://itdogkuwaccho.hatenadiary.com/entry/2017/11/12/125140)
|
96
96
|
|
97
97
|
|
98
|
-
以上、よろしくお願いします。
|
98
|
+
以上、よろしくお願いします。
|
99
|
+
|
100
|
+
##2020/2/17追記
|
101
|
+
|
102
|
+
DES形式でソースを修正しました。
|
103
|
+
```java
|
104
|
+
public static void main(String[] args) {
|
105
|
+
|
106
|
+
String key = "foobar00";
|
107
|
+
String origin = "hoge";
|
108
|
+
String enc = "U2FsdGVkX19eAkcLovbInztwfaMnjKwZ";
|
109
|
+
|
110
|
+
|
111
|
+
try {
|
112
|
+
/*
|
113
|
+
* 鍵
|
114
|
+
*/
|
115
|
+
// 秘密鍵を準備
|
116
|
+
byte[] kagi = key.getBytes();
|
117
|
+
DESKeySpec dk = new DESKeySpec(kagi);
|
118
|
+
Arrays.fill(kagi, (byte)0x00); // セキュリティ情報を上書きして削除
|
119
|
+
SecretKeyFactory kf = SecretKeyFactory.getInstance("DES");
|
120
|
+
SecretKey sk = kf.generateSecret(dk);
|
121
|
+
|
122
|
+
|
123
|
+
Cipher cipher = Cipher.getInstance("DES/ECB/PKCS5Padding");
|
124
|
+
cipher.init(Cipher.DECRYPT_MODE, sk);
|
125
|
+
Cipher c = Cipher.getInstance("DES");
|
126
|
+
|
127
|
+
//暗号化されたStringをデコード
|
128
|
+
byte[] enc_decode = Base64.getDecoder().decode(enc.getBytes());
|
129
|
+
|
130
|
+
//復号
|
131
|
+
byte[] output2 = c.doFinal(enc_decode);
|
132
|
+
|
133
|
+
|
134
|
+
// 表示
|
135
|
+
System.out.println("The string was ");
|
136
|
+
System.out.println(new String(output2));
|
137
|
+
|
138
|
+
|
139
|
+
} catch (Exception e) {
|
140
|
+
e.printStackTrace();
|
141
|
+
}
|
142
|
+
}
|
143
|
+
|
144
|
+
```
|
145
|
+
#実行結果
|
146
|
+
上記のソースを実行すると、下記エラーがでます。
|
147
|
+
|
148
|
+
> javax.crypto.BadPaddingException: Given final block not properly padded. Such issues can arise if a bad key is used during decryption.
|
149
|
+
at java.base/com.sun.crypto.provider.CipherCore.unpad(CipherCore.java:975)
|
150
|
+
at java.base/com.sun.crypto.provider.CipherCore.fillOutputBuffer(CipherCore.java:1056)
|
151
|
+
at java.base/com.sun.crypto.provider.CipherCore.doFinal(CipherCore.java:853)
|
152
|
+
at java.base/com.sun.crypto.provider.DESCipher.engineDoFinal(DESCipher.java:314)
|
153
|
+
at java.base/javax.crypto.Cipher.doFinal(Cipher.java:2202)
|
154
|
+
at com.example.demo.test2.main(test2.java:133)
|