質問編集履歴
1
DESで復号したソースに修正
test
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test
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@@ -193,3 +193,115 @@
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以上、よろしくお願いします。
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##2020/2/17追記
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DES形式でソースを修正しました。
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```java
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public static void main(String[] args) {
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String key = "foobar00";
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String origin = "hoge";
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String enc = "U2FsdGVkX19eAkcLovbInztwfaMnjKwZ";
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try {
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/*
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* 鍵
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*/
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// 秘密鍵を準備
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byte[] kagi = key.getBytes();
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DESKeySpec dk = new DESKeySpec(kagi);
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Arrays.fill(kagi, (byte)0x00); // セキュリティ情報を上書きして削除
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SecretKeyFactory kf = SecretKeyFactory.getInstance("DES");
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SecretKey sk = kf.generateSecret(dk);
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Cipher cipher = Cipher.getInstance("DES/ECB/PKCS5Padding");
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cipher.init(Cipher.DECRYPT_MODE, sk);
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Cipher c = Cipher.getInstance("DES");
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//暗号化されたStringをデコード
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byte[] enc_decode = Base64.getDecoder().decode(enc.getBytes());
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//復号
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byte[] output2 = c.doFinal(enc_decode);
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// 表示
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System.out.println("The string was ");
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System.out.println(new String(output2));
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} catch (Exception e) {
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e.printStackTrace();
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}
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}
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```
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#実行結果
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上記のソースを実行すると、下記エラーがでます。
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> javax.crypto.BadPaddingException: Given final block not properly padded. Such issues can arise if a bad key is used during decryption.
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at java.base/com.sun.crypto.provider.CipherCore.unpad(CipherCore.java:975)
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at java.base/com.sun.crypto.provider.CipherCore.fillOutputBuffer(CipherCore.java:1056)
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at java.base/com.sun.crypto.provider.CipherCore.doFinal(CipherCore.java:853)
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at java.base/com.sun.crypto.provider.DESCipher.engineDoFinal(DESCipher.java:314)
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at java.base/javax.crypto.Cipher.doFinal(Cipher.java:2202)
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at com.example.demo.test2.main(test2.java:133)
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